From 6433eeae66fc41a082ba571790aae858a58d5c68 Mon Sep 17 00:00:00 2001
From: geniusgogo <xpxyr@sina.com>
Date: Sun, 24 Nov 2013 01:52:49 +0800
Subject: build env component removal

---
 components/external/sqlite/sqlite3.c | 20938 ++++++---------------------------
 1 file changed, 3577 insertions(+), 17361 deletions(-)

(limited to 'components/external/sqlite/sqlite3.c')

diff --git a/components/external/sqlite/sqlite3.c b/components/external/sqlite/sqlite3.c
index c132cfc671..24de8db4b2 100644
--- a/components/external/sqlite/sqlite3.c
+++ b/components/external/sqlite/sqlite3.c
@@ -18144,7 +18144,7 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
 #endif /* !defined(SQLITE_MUTEX_OMIT) */
 
 /************** End of mutex_noop.c ******************************************/
-/************** Begin file mutex_unix.c **************************************/
+/************** Begin file mutex_rtt.c ***************************************/
 /*
 ** 2007 August 28
 **
@@ -18156,19 +18156,19 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains the C functions that implement mutexes for pthreads
+** This file contains the C functions that implement mutexes for rtthread
 */
 
 /*
 ** The code in this file is only used if we are compiling threadsafe
-** under unix with pthreads.
+** under rt-thread with rt_mutex.
 **
-** Note that this implementation requires a version of pthreads that
+** Note that this implementation requires a version of rt-thread that
 ** supports recursive mutexes.
 */
-#ifdef SQLITE_MUTEX_PTHREADS
+#ifdef SQLITE_MUTEX_RTT
 
-#include <pthread.h>
+/* #include <rtthread.h> */
 
 /*
 ** The sqlite3_mutex.id, sqlite3_mutex.nRef, and sqlite3_mutex.owner fields
@@ -18185,50 +18185,51 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
 ** Each recursive mutex is an instance of the following structure.
 */
 struct sqlite3_mutex {
-  pthread_mutex_t mutex;     /* Mutex controlling the lock */
+  struct rt_mutex mutex;     /* Mutex controlling the lock */
 #if SQLITE_MUTEX_NREF
   int id;                    /* Mutex type */
   volatile int nRef;         /* Number of entrances */
-  volatile pthread_t owner;  /* Thread that is within this mutex */
+  volatile rt_thread_t owner;  /* Thread that is within this mutex */
   int trace;                 /* True to trace changes */
 #endif
 };
+#define RTT_MUTEX_INITIALIZER   { 0 }
 #if SQLITE_MUTEX_NREF
-#define SQLITE3_MUTEX_INITIALIZER { PTHREAD_MUTEX_INITIALIZER, 0, 0, (pthread_t)0, 0 }
+#define SQLITE3_MUTEX_INITIALIZER { RTT_MUTEX_INITIALIZER, 0, 0, (rt_thread_t)0, 0 }
 #else
-#define SQLITE3_MUTEX_INITIALIZER { PTHREAD_MUTEX_INITIALIZER }
+#define SQLITE3_MUTEX_INITIALIZER { RTT_MUTEX_INITIALIZER }
 #endif
 
 /*
 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
 ** intended for use only inside assert() statements.  On some platforms,
 ** there might be race conditions that can cause these routines to
-** deliver incorrect results.  In particular, if pthread_equal() is
+** deliver incorrect results.  In particular, if rtt_equal() is
 ** not an atomic operation, then these routines might delivery
-** incorrect results.  On most platforms, pthread_equal() is a 
+** incorrect results.  On most platforms, rtt_equal() is a
 ** comparison of two integers and is therefore atomic.  But we are
 ** told that HPUX is not such a platform.  If so, then these routines
 ** will not always work correctly on HPUX.
 **
-** On those platforms where pthread_equal() is not atomic, SQLite
+** On those platforms where rtt_equal() is not atomic, SQLite
 ** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
 ** make sure no assert() statements are evaluated and hence these
 ** routines are never called.
 */
 #if !defined(NDEBUG) || defined(SQLITE_DEBUG)
-static int pthreadMutexHeld(sqlite3_mutex *p){
-  return (p->nRef!=0 && pthread_equal(p->owner, pthread_self()));
+static int rttMutexHeld(sqlite3_mutex *p){
+  return (p->nRef != 0 && p->owner == rt_thread_self());
 }
-static int pthreadMutexNotheld(sqlite3_mutex *p){
-  return p->nRef==0 || pthread_equal(p->owner, pthread_self())==0;
+static int rttMutexNotheld(sqlite3_mutex *p){
+  return (p->nRef == 0 || p->owner != rt_thread_self());
 }
 #endif
 
 /*
 ** Initialize and deinitialize the mutex subsystem.
 */
-static int pthreadMutexInit(void){ return SQLITE_OK; }
-static int pthreadMutexEnd(void){ return SQLITE_OK; }
+static int rttMutexInit(void){ return SQLITE_OK; }
+static int rttMutexEnd(void){ return SQLITE_OK; }
 
 /*
 ** The sqlite3_mutex_alloc() routine allocates a new
@@ -18268,11 +18269,11 @@ static int pthreadMutexEnd(void){ return SQLITE_OK; }
 **
 ** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  But for the static 
+** returns a different mutex on every call.  But for the static
 ** mutex types, the same mutex is returned on every call that has
 ** the same type number.
 */
-static sqlite3_mutex *pthreadMutexAlloc(int iType){
+static sqlite3_mutex *rttMutexAlloc(int iType){
   static sqlite3_mutex staticMutexes[] = {
     SQLITE3_MUTEX_INITIALIZER,
     SQLITE3_MUTEX_INITIALIZER,
@@ -18286,18 +18287,8 @@ static sqlite3_mutex *pthreadMutexAlloc(int iType){
     case SQLITE_MUTEX_RECURSIVE: {
       p = sqlite3MallocZero( sizeof(*p) );
       if( p ){
-#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
-        /* If recursive mutexes are not available, we will have to
-        ** build our own.  See below. */
-        pthread_mutex_init(&p->mutex, 0);
-#else
         /* Use a recursive mutex if it is available */
-        pthread_mutexattr_t recursiveAttr;
-        pthread_mutexattr_init(&recursiveAttr);
-        pthread_mutexattr_settype(&recursiveAttr, PTHREAD_MUTEX_RECURSIVE);
-        pthread_mutex_init(&p->mutex, &recursiveAttr);
-        pthread_mutexattr_destroy(&recursiveAttr);
-#endif
+       rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
 #if SQLITE_MUTEX_NREF
         p->id = iType;
 #endif
@@ -18310,7 +18301,7 @@ static sqlite3_mutex *pthreadMutexAlloc(int iType){
 #if SQLITE_MUTEX_NREF
         p->id = iType;
 #endif
-        pthread_mutex_init(&p->mutex, 0);
+        rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
       }
       break;
     }
@@ -18321,6 +18312,7 @@ static sqlite3_mutex *pthreadMutexAlloc(int iType){
 #if SQLITE_MUTEX_NREF
       p->id = iType;
 #endif
+      rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
       break;
     }
   }
@@ -18333,10 +18325,10 @@ static sqlite3_mutex *pthreadMutexAlloc(int iType){
 ** allocated mutex.  SQLite is careful to deallocate every
 ** mutex that it allocates.
 */
-static void pthreadMutexFree(sqlite3_mutex *p){
+static void rttMutexFree(sqlite3_mutex *p){
   assert( p->nRef==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
-  pthread_mutex_destroy(&p->mutex);
+  rt_mutex_detach(&p->mutex);
   sqlite3_free(p);
 }
 
@@ -18351,26 +18343,26 @@ static void pthreadMutexFree(sqlite3_mutex *p){
 ** can enter.  If the same thread tries to enter any other kind of mutex
 ** more than once, the behavior is undefined.
 */
-static void pthreadMutexEnter(sqlite3_mutex *p){
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+static void rttMutexEnter(sqlite3_mutex *p){
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || rttMutexNotheld(p) );
 
 #ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
   /* If recursive mutexes are not available, then we have to grow
-  ** our own.  This implementation assumes that pthread_equal()
+  ** our own.  This implementation assumes that rtt_equal()
   ** is atomic - that it cannot be deceived into thinking self
   ** and p->owner are equal if p->owner changes between two values
   ** that are not equal to self while the comparison is taking place.
-  ** This implementation also assumes a coherent cache - that 
+  ** This implementation also assumes a coherent cache - that
   ** separate processes cannot read different values from the same
   ** address at the same time.  If either of these two conditions
   ** are not met, then the mutexes will fail and problems will result.
   */
   {
-    pthread_t self = pthread_self();
-    if( p->nRef>0 && pthread_equal(p->owner, self) ){
+    rt_thread_t self = rt_thread_self();
+    if( p->nRef>0 && (p->owner == self) ){
       p->nRef++;
     }else{
-      pthread_mutex_lock(&p->mutex);
+      rt_mutex_take(&p->mutex, RT_WAITING_FOREVER);
       assert( p->nRef==0 );
       p->owner = self;
       p->nRef = 1;
@@ -18379,41 +18371,41 @@ static void pthreadMutexEnter(sqlite3_mutex *p){
 #else
   /* Use the built-in recursive mutexes if they are available.
   */
-  pthread_mutex_lock(&p->mutex);
+  rt_mutex_take(&p->mutex, RT_WAITING_FOREVER);
 #if SQLITE_MUTEX_NREF
   assert( p->nRef>0 || p->owner==0 );
-  p->owner = pthread_self();
+  p->owner = rt_thread_self();
   p->nRef++;
 #endif
 #endif
 
 #ifdef SQLITE_DEBUG
   if( p->trace ){
-    printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+    rt_kprintf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
   }
 #endif
 }
-static int pthreadMutexTry(sqlite3_mutex *p){
+static int rttMutexTry(sqlite3_mutex *p){
   int rc;
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+  assert( p->id==SQLITE_MUTEX_RECURSIVE || rttMutexNotheld(p) );
 
 #ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
   /* If recursive mutexes are not available, then we have to grow
-  ** our own.  This implementation assumes that pthread_equal()
+  ** our own.  This implementation assumes that rtt_equal()
   ** is atomic - that it cannot be deceived into thinking self
   ** and p->owner are equal if p->owner changes between two values
   ** that are not equal to self while the comparison is taking place.
-  ** This implementation also assumes a coherent cache - that 
+  ** This implementation also assumes a coherent cache - that
   ** separate processes cannot read different values from the same
   ** address at the same time.  If either of these two conditions
   ** are not met, then the mutexes will fail and problems will result.
   */
   {
-    pthread_t self = pthread_self();
-    if( p->nRef>0 && pthread_equal(p->owner, self) ){
+    rt_thread_t self = rt_thread_self();
+    if( p->nRef>0 && (p->owner == self) ){
       p->nRef++;
       rc = SQLITE_OK;
-    }else if( pthread_mutex_trylock(&p->mutex)==0 ){
+    }else if( rt_mutex_take(&p->mutex, RT_WAITING_NO)==RT_EOK ){
       assert( p->nRef==0 );
       p->owner = self;
       p->nRef = 1;
@@ -18425,9 +18417,9 @@ static int pthreadMutexTry(sqlite3_mutex *p){
 #else
   /* Use the built-in recursive mutexes if they are available.
   */
-  if( pthread_mutex_trylock(&p->mutex)==0 ){
+  if( rt_mutex_take(&p->mutex, RT_WAITING_NO)==RT_EOK ){
 #if SQLITE_MUTEX_NREF
-    p->owner = pthread_self();
+    p->owner = rt_thread_self();
     p->nRef++;
 #endif
     rc = SQLITE_OK;
@@ -18438,7 +18430,7 @@ static int pthreadMutexTry(sqlite3_mutex *p){
 
 #ifdef SQLITE_DEBUG
   if( rc==SQLITE_OK && p->trace ){
-    printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+    rt_kprintf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
   }
 #endif
   return rc;
@@ -18450,8 +18442,8 @@ static int pthreadMutexTry(sqlite3_mutex *p){
 ** is undefined if the mutex is not currently entered or
 ** is not currently allocated.  SQLite will never do either.
 */
-static void pthreadMutexLeave(sqlite3_mutex *p){
-  assert( pthreadMutexHeld(p) );
+static void rttMutexLeave(sqlite3_mutex *p){
+  assert( rttMutexHeld(p) );
 #if SQLITE_MUTEX_NREF
   p->nRef--;
   if( p->nRef==0 ) p->owner = 0;
@@ -18460,31 +18452,31 @@ static void pthreadMutexLeave(sqlite3_mutex *p){
 
 #ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
   if( p->nRef==0 ){
-    pthread_mutex_unlock(&p->mutex);
+    rt_mutex_release(&p->mutex);
   }
 #else
-  pthread_mutex_unlock(&p->mutex);
+  rt_mutex_release(&p->mutex);
 #endif
 
 #ifdef SQLITE_DEBUG
   if( p->trace ){
-    printf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+    rt_kprintf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
   }
 #endif
 }
 
 SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
   static const sqlite3_mutex_methods sMutex = {
-    pthreadMutexInit,
-    pthreadMutexEnd,
-    pthreadMutexAlloc,
-    pthreadMutexFree,
-    pthreadMutexEnter,
-    pthreadMutexTry,
-    pthreadMutexLeave,
+    rttMutexInit,
+    rttMutexEnd,
+    rttMutexAlloc,
+    rttMutexFree,
+    rttMutexEnter,
+    rttMutexTry,
+    rttMutexLeave,
 #ifdef SQLITE_DEBUG
-    pthreadMutexHeld,
-    pthreadMutexNotheld
+    rttMutexHeld,
+    rttMutexNotheld
 #else
     0,
     0
@@ -18494,12 +18486,13 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
   return &sMutex;
 }
 
-#endif /* SQLITE_MUTEX_PTHREADS */
+#endif /* SQLITE_MUTEX_RTT */
+
 
-/************** End of mutex_unix.c ******************************************/
-/************** Begin file mutex_w32.c ***************************************/
+/************** End of mutex_rtt.c *******************************************/
+/************** Begin file malloc.c ******************************************/
 /*
-** 2007 August 14
+** 2001 September 15
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -18509,17912 +18502,4135 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This file contains the C functions that implement mutexes for win32
+**
+** Memory allocation functions used throughout sqlite.
 */
+/* #include <stdarg.h> */
 
 /*
-** The code in this file is only used if we are compiling multithreaded
-** on a win32 system.
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
 */
-#ifdef SQLITE_MUTEX_W32
+SQLITE_API int sqlite3_release_memory(int n){
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+  return sqlite3PcacheReleaseMemory(n);
+#else
+  /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
+  ** is a no-op returning zero if SQLite is not compiled with
+  ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
+  UNUSED_PARAMETER(n);
+  return 0;
+#endif
+}
 
 /*
-** Each recursive mutex is an instance of the following structure.
+** An instance of the following object records the location of
+** each unused scratch buffer.
 */
-struct sqlite3_mutex {
-  CRITICAL_SECTION mutex;    /* Mutex controlling the lock */
-  int id;                    /* Mutex type */
-#ifdef SQLITE_DEBUG
-  volatile int nRef;         /* Number of enterances */
-  volatile DWORD owner;      /* Thread holding this mutex */
-  int trace;                 /* True to trace changes */
-#endif
-};
-#define SQLITE_W32_MUTEX_INITIALIZER { 0 }
-#ifdef SQLITE_DEBUG
-#define SQLITE3_MUTEX_INITIALIZER { SQLITE_W32_MUTEX_INITIALIZER, 0, 0L, (DWORD)0, 0 }
-#else
-#define SQLITE3_MUTEX_INITIALIZER { SQLITE_W32_MUTEX_INITIALIZER, 0 }
-#endif
+typedef struct ScratchFreeslot {
+  struct ScratchFreeslot *pNext;   /* Next unused scratch buffer */
+} ScratchFreeslot;
 
 /*
-** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
-** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
-**
-** Here is an interesting observation:  Win95, Win98, and WinME lack
-** the LockFileEx() API.  But we can still statically link against that
-** API as long as we don't call it win running Win95/98/ME.  A call to
-** this routine is used to determine if the host is Win95/98/ME or
-** WinNT/2K/XP so that we will know whether or not we can safely call
-** the LockFileEx() API.
-**
-** mutexIsNT() is only used for the TryEnterCriticalSection() API call,
-** which is only available if your application was compiled with 
-** _WIN32_WINNT defined to a value >= 0x0400.  Currently, the only
-** call to TryEnterCriticalSection() is #ifdef'ed out, so #ifdef 
-** this out as well.
+** State information local to the memory allocation subsystem.
 */
-#if 0
-#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
-# define mutexIsNT()  (1)
-#else
-  static int mutexIsNT(void){
-    static int osType = 0;
-    if( osType==0 ){
-      OSVERSIONINFO sInfo;
-      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
-      GetVersionEx(&sInfo);
-      osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
-    }
-    return osType==2;
-  }
-#endif /* SQLITE_OS_WINCE || SQLITE_OS_WINRT */
-#endif
+static SQLITE_WSD struct Mem0Global {
+  sqlite3_mutex *mutex;         /* Mutex to serialize access */
+
+  /*
+  ** The alarm callback and its arguments.  The mem0.mutex lock will
+  ** be held while the callback is running.  Recursive calls into
+  ** the memory subsystem are allowed, but no new callbacks will be
+  ** issued.
+  */
+  sqlite3_int64 alarmThreshold;
+  void (*alarmCallback)(void*, sqlite3_int64,int);
+  void *alarmArg;
+
+  /*
+  ** Pointers to the end of sqlite3GlobalConfig.pScratch memory
+  ** (so that a range test can be used to determine if an allocation
+  ** being freed came from pScratch) and a pointer to the list of
+  ** unused scratch allocations.
+  */
+  void *pScratchEnd;
+  ScratchFreeslot *pScratchFree;
+  u32 nScratchFree;
+
+  /*
+  ** True if heap is nearly "full" where "full" is defined by the
+  ** sqlite3_soft_heap_limit() setting.
+  */
+  int nearlyFull;
+} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
 
-#ifdef SQLITE_DEBUG
 /*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use only inside assert() statements.
+** This routine runs when the memory allocator sees that the
+** total memory allocation is about to exceed the soft heap
+** limit.
 */
-static int winMutexHeld(sqlite3_mutex *p){
-  return p->nRef!=0 && p->owner==GetCurrentThreadId();
+static void softHeapLimitEnforcer(
+  void *NotUsed, 
+  sqlite3_int64 NotUsed2,
+  int allocSize
+){
+  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  sqlite3_release_memory(allocSize);
 }
-static int winMutexNotheld2(sqlite3_mutex *p, DWORD tid){
-  return p->nRef==0 || p->owner!=tid;
+
+/*
+** Change the alarm callback
+*/
+static int sqlite3MemoryAlarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  int nUsed;
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
+  mem0.alarmThreshold = iThreshold;
+  nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+  mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed);
+  sqlite3_mutex_leave(mem0.mutex);
+  return SQLITE_OK;
 }
-static int winMutexNotheld(sqlite3_mutex *p){
-  DWORD tid = GetCurrentThreadId(); 
-  return winMutexNotheld2(p, tid);
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface.  Internal/core SQLite code
+** should call sqlite3MemoryAlarm.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
 }
 #endif
 
-
 /*
-** Initialize and deinitialize the mutex subsystem.
-*/
-static sqlite3_mutex winMutex_staticMutexes[6] = {
-  SQLITE3_MUTEX_INITIALIZER,
-  SQLITE3_MUTEX_INITIALIZER,
-  SQLITE3_MUTEX_INITIALIZER,
-  SQLITE3_MUTEX_INITIALIZER,
-  SQLITE3_MUTEX_INITIALIZER,
-  SQLITE3_MUTEX_INITIALIZER
-};
-static int winMutex_isInit = 0;
-/* As winMutexInit() and winMutexEnd() are called as part
-** of the sqlite3_initialize and sqlite3_shutdown()
-** processing, the "interlocked" magic is probably not
-** strictly necessary.
+** Set the soft heap-size limit for the library. Passing a zero or 
+** negative value indicates no limit.
 */
-static LONG winMutex_lock = 0;
-
-SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */
-
-static int winMutexInit(void){ 
-  /* The first to increment to 1 does actual initialization */
-  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
-    int i;
-    for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
-#if SQLITE_OS_WINRT
-      InitializeCriticalSectionEx(&winMutex_staticMutexes[i].mutex, 0, 0);
-#else
-      InitializeCriticalSection(&winMutex_staticMutexes[i].mutex);
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
+  sqlite3_int64 priorLimit;
+  sqlite3_int64 excess;
+#ifndef SQLITE_OMIT_AUTOINIT
+  int rc = sqlite3_initialize();
+  if( rc ) return -1;
 #endif
-    }
-    winMutex_isInit = 1;
+  sqlite3_mutex_enter(mem0.mutex);
+  priorLimit = mem0.alarmThreshold;
+  sqlite3_mutex_leave(mem0.mutex);
+  if( n<0 ) return priorLimit;
+  if( n>0 ){
+    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n);
   }else{
-    /* Someone else is in the process of initing the static mutexes */
-    while( !winMutex_isInit ){
-      sqlite3_win32_sleep(1);
-    }
+    sqlite3MemoryAlarm(0, 0, 0);
   }
-  return SQLITE_OK; 
+  excess = sqlite3_memory_used() - n;
+  if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff));
+  return priorLimit;
+}
+SQLITE_API void sqlite3_soft_heap_limit(int n){
+  if( n<0 ) n = 0;
+  sqlite3_soft_heap_limit64(n);
 }
 
-static int winMutexEnd(void){ 
-  /* The first to decrement to 0 does actual shutdown 
-  ** (which should be the last to shutdown.) */
-  if( InterlockedCompareExchange(&winMutex_lock, 0, 1)==1 ){
-    if( winMutex_isInit==1 ){
-      int i;
-      for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
-        DeleteCriticalSection(&winMutex_staticMutexes[i].mutex);
-      }
-      winMutex_isInit = 0;
+/*
+** Initialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE int sqlite3MallocInit(void){
+  if( sqlite3GlobalConfig.m.xMalloc==0 ){
+    sqlite3MemSetDefault();
+  }
+  memset(&mem0, 0, sizeof(mem0));
+  if( sqlite3GlobalConfig.bCoreMutex ){
+    mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+  }
+  if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
+      && sqlite3GlobalConfig.nScratch>0 ){
+    int i, n, sz;
+    ScratchFreeslot *pSlot;
+    sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
+    sqlite3GlobalConfig.szScratch = sz;
+    pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;
+    n = sqlite3GlobalConfig.nScratch;
+    mem0.pScratchFree = pSlot;
+    mem0.nScratchFree = n;
+    for(i=0; i<n-1; i++){
+      pSlot->pNext = (ScratchFreeslot*)(sz+(char*)pSlot);
+      pSlot = pSlot->pNext;
     }
+    pSlot->pNext = 0;
+    mem0.pScratchEnd = (void*)&pSlot[1];
+  }else{
+    mem0.pScratchEnd = 0;
+    sqlite3GlobalConfig.pScratch = 0;
+    sqlite3GlobalConfig.szScratch = 0;
+    sqlite3GlobalConfig.nScratch = 0;
+  }
+  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+      || sqlite3GlobalConfig.nPage<1 ){
+    sqlite3GlobalConfig.pPage = 0;
+    sqlite3GlobalConfig.szPage = 0;
+    sqlite3GlobalConfig.nPage = 0;
   }
-  return SQLITE_OK; 
+  return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
 }
 
 /*
-** The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it.  If it returns NULL
-** that means that a mutex could not be allocated.  SQLite
-** will unwind its stack and return an error.  The argument
-** to sqlite3_mutex_alloc() is one of these integer constants:
-**
-** <ul>
-** <li>  SQLITE_MUTEX_FAST
-** <li>  SQLITE_MUTEX_RECURSIVE
-** <li>  SQLITE_MUTEX_STATIC_MASTER
-** <li>  SQLITE_MUTEX_STATIC_MEM
-** <li>  SQLITE_MUTEX_STATIC_MEM2
-** <li>  SQLITE_MUTEX_STATIC_PRNG
-** <li>  SQLITE_MUTEX_STATIC_LRU
-** <li>  SQLITE_MUTEX_STATIC_PMEM
-** </ul>
-**
-** The first two constants cause sqlite3_mutex_alloc() to create
-** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
-** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
-** The mutex implementation does not need to make a distinction
-** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  But SQLite will only request a recursive mutex in
-** cases where it really needs one.  If a faster non-recursive mutex
-** implementation is available on the host platform, the mutex subsystem
-** might return such a mutex in response to SQLITE_MUTEX_FAST.
-**
-** The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex.  Six static mutexes are
-** used by the current version of SQLite.  Future versions of SQLite
-** may add additional static mutexes.  Static mutexes are for internal
-** use by SQLite only.  Applications that use SQLite mutexes should
-** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
-** SQLITE_MUTEX_RECURSIVE.
-**
-** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
-** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  But for the static 
-** mutex types, the same mutex is returned on every call that has
-** the same type number.
+** Return true if the heap is currently under memory pressure - in other
+** words if the amount of heap used is close to the limit set by
+** sqlite3_soft_heap_limit().
 */
-static sqlite3_mutex *winMutexAlloc(int iType){
-  sqlite3_mutex *p;
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
+  return mem0.nearlyFull;
+}
 
-  switch( iType ){
-    case SQLITE_MUTEX_FAST:
-    case SQLITE_MUTEX_RECURSIVE: {
-      p = sqlite3MallocZero( sizeof(*p) );
-      if( p ){  
-#ifdef SQLITE_DEBUG
-        p->id = iType;
-#endif
-#if SQLITE_OS_WINRT
-        InitializeCriticalSectionEx(&p->mutex, 0, 0);
-#else
-        InitializeCriticalSection(&p->mutex);
-#endif
-      }
-      break;
-    }
-    default: {
-      assert( winMutex_isInit==1 );
-      assert( iType-2 >= 0 );
-      assert( iType-2 < ArraySize(winMutex_staticMutexes) );
-      p = &winMutex_staticMutexes[iType-2];
-#ifdef SQLITE_DEBUG
-      p->id = iType;
-#endif
-      break;
-    }
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE void sqlite3MallocEnd(void){
+  if( sqlite3GlobalConfig.m.xShutdown ){
+    sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData);
   }
-  return p;
+  memset(&mem0, 0, sizeof(mem0));
 }
 
+/*
+** Return the amount of memory currently checked out.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
+  int n, mx;
+  sqlite3_int64 res;
+  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, 0);
+  res = (sqlite3_int64)n;  /* Work around bug in Borland C. Ticket #3216 */
+  return res;
+}
 
 /*
-** This routine deallocates a previously
-** allocated mutex.  SQLite is careful to deallocate every
-** mutex that it allocates.
+** Return the maximum amount of memory that has ever been
+** checked out since either the beginning of this process
+** or since the most recent reset.
 */
-static void winMutexFree(sqlite3_mutex *p){
-  assert( p );
-  assert( p->nRef==0 && p->owner==0 );
-  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
-  DeleteCriticalSection(&p->mutex);
-  sqlite3_free(p);
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
+  int n, mx;
+  sqlite3_int64 res;
+  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, resetFlag);
+  res = (sqlite3_int64)mx;  /* Work around bug in Borland C. Ticket #3216 */
+  return res;
 }
 
 /*
-** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex.  If another thread is already within the mutex,
-** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
-** be entered multiple times by the same thread.  In such cases the,
-** mutex must be exited an equal number of times before another thread
-** can enter.  If the same thread tries to enter any other kind of mutex
-** more than once, the behavior is undefined.
+** Trigger the alarm 
 */
-static void winMutexEnter(sqlite3_mutex *p){
-#ifdef SQLITE_DEBUG
-  DWORD tid = GetCurrentThreadId(); 
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
-#endif
-  EnterCriticalSection(&p->mutex);
-#ifdef SQLITE_DEBUG
-  assert( p->nRef>0 || p->owner==0 );
-  p->owner = tid; 
-  p->nRef++;
-  if( p->trace ){
-    printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
-  }
-#endif
+static void sqlite3MallocAlarm(int nByte){
+  void (*xCallback)(void*,sqlite3_int64,int);
+  sqlite3_int64 nowUsed;
+  void *pArg;
+  if( mem0.alarmCallback==0 ) return;
+  xCallback = mem0.alarmCallback;
+  nowUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+  pArg = mem0.alarmArg;
+  mem0.alarmCallback = 0;
+  sqlite3_mutex_leave(mem0.mutex);
+  xCallback(pArg, nowUsed, nByte);
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
 }
-static int winMutexTry(sqlite3_mutex *p){
-#ifndef NDEBUG
-  DWORD tid = GetCurrentThreadId(); 
-#endif
-  int rc = SQLITE_BUSY;
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
-  /*
-  ** The sqlite3_mutex_try() routine is very rarely used, and when it
-  ** is used it is merely an optimization.  So it is OK for it to always
-  ** fail.  
-  **
-  ** The TryEnterCriticalSection() interface is only available on WinNT.
-  ** And some windows compilers complain if you try to use it without
-  ** first doing some #defines that prevent SQLite from building on Win98.
-  ** For that reason, we will omit this optimization for now.  See
-  ** ticket #2685.
-  */
-#if 0
-  if( mutexIsNT() && TryEnterCriticalSection(&p->mutex) ){
-    p->owner = tid;
-    p->nRef++;
-    rc = SQLITE_OK;
+
+/*
+** Do a memory allocation with statistics and alarms.  Assume the
+** lock is already held.
+*/
+static int mallocWithAlarm(int n, void **pp){
+  int nFull;
+  void *p;
+  assert( sqlite3_mutex_held(mem0.mutex) );
+  nFull = sqlite3GlobalConfig.m.xRoundup(n);
+  sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n);
+  if( mem0.alarmCallback!=0 ){
+    int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+    if( nUsed >= mem0.alarmThreshold - nFull ){
+      mem0.nearlyFull = 1;
+      sqlite3MallocAlarm(nFull);
+    }else{
+      mem0.nearlyFull = 0;
+    }
   }
-#else
-  UNUSED_PARAMETER(p);
-#endif
-#ifdef SQLITE_DEBUG
-  if( rc==SQLITE_OK && p->trace ){
-    printf("try mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+  p = sqlite3GlobalConfig.m.xMalloc(nFull);
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+  if( p==0 && mem0.alarmCallback ){
+    sqlite3MallocAlarm(nFull);
+    p = sqlite3GlobalConfig.m.xMalloc(nFull);
   }
 #endif
-  return rc;
+  if( p ){
+    nFull = sqlite3MallocSize(p);
+    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1);
+  }
+  *pp = p;
+  return nFull;
 }
 
 /*
-** The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  The behavior
-** is undefined if the mutex is not currently entered or
-** is not currently allocated.  SQLite will never do either.
+** Allocate memory.  This routine is like sqlite3_malloc() except that it
+** assumes the memory subsystem has already been initialized.
 */
-static void winMutexLeave(sqlite3_mutex *p){
-#ifndef NDEBUG
-  DWORD tid = GetCurrentThreadId();
-  assert( p->nRef>0 );
-  assert( p->owner==tid );
-  p->nRef--;
-  if( p->nRef==0 ) p->owner = 0;
-  assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
-#endif
-  LeaveCriticalSection(&p->mutex);
-#ifdef SQLITE_DEBUG
-  if( p->trace ){
-    printf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+SQLITE_PRIVATE void *sqlite3Malloc(int n){
+  void *p;
+  if( n<=0               /* IMP: R-65312-04917 */ 
+   || n>=0x7fffff00
+  ){
+    /* A memory allocation of a number of bytes which is near the maximum
+    ** signed integer value might cause an integer overflow inside of the
+    ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
+    ** 255 bytes of overhead.  SQLite itself will never use anything near
+    ** this amount.  The only way to reach the limit is with sqlite3_malloc() */
+    p = 0;
+  }else if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    mallocWithAlarm(n, &p);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    p = sqlite3GlobalConfig.m.xMalloc(n);
   }
-#endif
-}
-
-SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
-  static const sqlite3_mutex_methods sMutex = {
-    winMutexInit,
-    winMutexEnd,
-    winMutexAlloc,
-    winMutexFree,
-    winMutexEnter,
-    winMutexTry,
-    winMutexLeave,
-#ifdef SQLITE_DEBUG
-    winMutexHeld,
-    winMutexNotheld
-#else
-    0,
-    0
-#endif
-  };
-
-  return &sMutex;
+  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-04675-44850 */
+  return p;
 }
-#endif /* SQLITE_MUTEX_W32 */
 
-/************** End of mutex_w32.c *******************************************/
-/************** Begin file mutex_rtt.c ***************************************/
 /*
-** 2007 August 28
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains the C functions that implement mutexes for rtthread
+** This version of the memory allocation is for use by the application.
+** First make sure the memory subsystem is initialized, then do the
+** allocation.
 */
+SQLITE_API void *sqlite3_malloc(int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  return sqlite3Malloc(n);
+}
 
 /*
-** The code in this file is only used if we are compiling threadsafe
-** under rt-thread with rt_mutex.
-**
-** Note that this implementation requires a version of rt-thread that
-** supports recursive mutexes.
+** Each thread may only have a single outstanding allocation from
+** xScratchMalloc().  We verify this constraint in the single-threaded
+** case by setting scratchAllocOut to 1 when an allocation
+** is outstanding clearing it when the allocation is freed.
 */
-#ifdef SQLITE_MUTEX_RTT
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+static int scratchAllocOut = 0;
+#endif
 
-/* #include <rtthread.h> */
 
 /*
-** The sqlite3_mutex.id, sqlite3_mutex.nRef, and sqlite3_mutex.owner fields
-** are necessary under two condidtions:  (1) Debug builds and (2) using
-** home-grown mutexes.  Encapsulate these conditions into a single #define.
+** Allocate memory that is to be used and released right away.
+** This routine is similar to alloca() in that it is not intended
+** for situations where the memory might be held long-term.  This
+** routine is intended to get memory to old large transient data
+** structures that would not normally fit on the stack of an
+** embedded processor.
 */
-#if defined(SQLITE_DEBUG) || defined(SQLITE_HOMEGROWN_RECURSIVE_MUTEX)
-# define SQLITE_MUTEX_NREF 1
-#else
-# define SQLITE_MUTEX_NREF 0
+SQLITE_PRIVATE void *sqlite3ScratchMalloc(int n){
+  void *p;
+  assert( n>0 );
+
+  sqlite3_mutex_enter(mem0.mutex);
+  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
+    p = mem0.pScratchFree;
+    mem0.pScratchFree = mem0.pScratchFree->pNext;
+    mem0.nScratchFree--;
+    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
+    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    if( sqlite3GlobalConfig.bMemstat ){
+      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+      n = mallocWithAlarm(n, &p);
+      if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      sqlite3_mutex_leave(mem0.mutex);
+      p = sqlite3GlobalConfig.m.xMalloc(n);
+    }
+    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
+  }
+  assert( sqlite3_mutex_notheld(mem0.mutex) );
+
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+  /* Verify that no more than two scratch allocations per thread
+  ** are outstanding at one time.  (This is only checked in the
+  ** single-threaded case since checking in the multi-threaded case
+  ** would be much more complicated.) */
+  assert( scratchAllocOut<=1 );
+  if( p ) scratchAllocOut++;
+#endif
+
+  return p;
+}
+SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
+  if( p ){
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+    /* Verify that no more than two scratch allocation per thread
+    ** is outstanding at one time.  (This is only checked in the
+    ** single-threaded case since checking in the multi-threaded case
+    ** would be much more complicated.) */
+    assert( scratchAllocOut>=1 && scratchAllocOut<=2 );
+    scratchAllocOut--;
 #endif
 
+    if( p>=sqlite3GlobalConfig.pScratch && p<mem0.pScratchEnd ){
+      /* Release memory from the SQLITE_CONFIG_SCRATCH allocation */
+      ScratchFreeslot *pSlot;
+      pSlot = (ScratchFreeslot*)p;
+      sqlite3_mutex_enter(mem0.mutex);
+      pSlot->pNext = mem0.pScratchFree;
+      mem0.pScratchFree = pSlot;
+      mem0.nScratchFree++;
+      assert( mem0.nScratchFree <= (u32)sqlite3GlobalConfig.nScratch );
+      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      /* Release memory back to the heap */
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
+      assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) );
+      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+      if( sqlite3GlobalConfig.bMemstat ){
+        int iSize = sqlite3MallocSize(p);
+        sqlite3_mutex_enter(mem0.mutex);
+        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+        sqlite3GlobalConfig.m.xFree(p);
+        sqlite3_mutex_leave(mem0.mutex);
+      }else{
+        sqlite3GlobalConfig.m.xFree(p);
+      }
+    }
+  }
+}
+
 /*
-** Each recursive mutex is an instance of the following structure.
+** TRUE if p is a lookaside memory allocation from db
 */
-struct sqlite3_mutex {
-  struct rt_mutex mutex;     /* Mutex controlling the lock */
-#if SQLITE_MUTEX_NREF
-  int id;                    /* Mutex type */
-  volatile int nRef;         /* Number of entrances */
-  volatile rt_thread_t owner;  /* Thread that is within this mutex */
-  int trace;                 /* True to trace changes */
-#endif
-};
-#define RTT_MUTEX_INITIALIZER   { 0 }
-#if SQLITE_MUTEX_NREF
-#define SQLITE3_MUTEX_INITIALIZER { RTT_MUTEX_INITIALIZER, 0, 0, (rt_thread_t)0, 0 }
+#ifndef SQLITE_OMIT_LOOKASIDE
+static int isLookaside(sqlite3 *db, void *p){
+  return p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
+}
 #else
-#define SQLITE3_MUTEX_INITIALIZER { RTT_MUTEX_INITIALIZER }
+#define isLookaside(A,B) 0
 #endif
 
 /*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use only inside assert() statements.  On some platforms,
-** there might be race conditions that can cause these routines to
-** deliver incorrect results.  In particular, if rtt_equal() is
-** not an atomic operation, then these routines might delivery
-** incorrect results.  On most platforms, rtt_equal() is a
-** comparison of two integers and is therefore atomic.  But we are
-** told that HPUX is not such a platform.  If so, then these routines
-** will not always work correctly on HPUX.
-**
-** On those platforms where rtt_equal() is not atomic, SQLite
-** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
-** make sure no assert() statements are evaluated and hence these
-** routines are never called.
+** Return the size of a memory allocation previously obtained from
+** sqlite3Malloc() or sqlite3_malloc().
 */
-#if !defined(NDEBUG) || defined(SQLITE_DEBUG)
-static int rttMutexHeld(sqlite3_mutex *p){
-  return (p->nRef != 0 && p->owner == rt_thread_self());
+SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+  return sqlite3GlobalConfig.m.xSize(p);
 }
-static int rttMutexNotheld(sqlite3_mutex *p){
-  return (p->nRef == 0 || p->owner != rt_thread_self());
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  if( db && isLookaside(db, p) ){
+    return db->lookaside.sz;
+  }else{
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+    assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+    return sqlite3GlobalConfig.m.xSize(p);
+  }
 }
-#endif
 
 /*
-** Initialize and deinitialize the mutex subsystem.
+** Free memory previously obtained from sqlite3Malloc().
 */
-static int rttMutexInit(void){ return SQLITE_OK; }
-static int rttMutexEnd(void){ return SQLITE_OK; }
+SQLITE_API void sqlite3_free(void *p){
+  if( p==0 ) return;  /* IMP: R-49053-54554 */
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+  if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+    sqlite3GlobalConfig.m.xFree(p);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    sqlite3GlobalConfig.m.xFree(p);
+  }
+}
 
 /*
-** The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it.  If it returns NULL
-** that means that a mutex could not be allocated.  SQLite
-** will unwind its stack and return an error.  The argument
-** to sqlite3_mutex_alloc() is one of these integer constants:
-**
-** <ul>
-** <li>  SQLITE_MUTEX_FAST
-** <li>  SQLITE_MUTEX_RECURSIVE
-** <li>  SQLITE_MUTEX_STATIC_MASTER
-** <li>  SQLITE_MUTEX_STATIC_MEM
-** <li>  SQLITE_MUTEX_STATIC_MEM2
-** <li>  SQLITE_MUTEX_STATIC_PRNG
-** <li>  SQLITE_MUTEX_STATIC_LRU
-** <li>  SQLITE_MUTEX_STATIC_PMEM
-** </ul>
-**
-** The first two constants cause sqlite3_mutex_alloc() to create
-** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
-** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
-** The mutex implementation does not need to make a distinction
-** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  But SQLite will only request a recursive mutex in
-** cases where it really needs one.  If a faster non-recursive mutex
-** implementation is available on the host platform, the mutex subsystem
-** might return such a mutex in response to SQLITE_MUTEX_FAST.
-**
-** The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex.  Six static mutexes are
-** used by the current version of SQLite.  Future versions of SQLite
-** may add additional static mutexes.  Static mutexes are for internal
-** use by SQLite only.  Applications that use SQLite mutexes should
-** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
-** SQLITE_MUTEX_RECURSIVE.
-**
-** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
-** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  But for the static
-** mutex types, the same mutex is returned on every call that has
-** the same type number.
+** Free memory that might be associated with a particular database
+** connection.
 */
-static sqlite3_mutex *rttMutexAlloc(int iType){
-  static sqlite3_mutex staticMutexes[] = {
-    SQLITE3_MUTEX_INITIALIZER,
-    SQLITE3_MUTEX_INITIALIZER,
-    SQLITE3_MUTEX_INITIALIZER,
-    SQLITE3_MUTEX_INITIALIZER,
-    SQLITE3_MUTEX_INITIALIZER,
-    SQLITE3_MUTEX_INITIALIZER
-  };
-  sqlite3_mutex *p;
-  switch( iType ){
-    case SQLITE_MUTEX_RECURSIVE: {
-      p = sqlite3MallocZero( sizeof(*p) );
-      if( p ){
-        /* Use a recursive mutex if it is available */
-       rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
-#if SQLITE_MUTEX_NREF
-        p->id = iType;
-#endif
-      }
-      break;
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  if( p==0 ) return;
+  if( db ){
+    if( db->pnBytesFreed ){
+      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
+      return;
     }
-    case SQLITE_MUTEX_FAST: {
-      p = sqlite3MallocZero( sizeof(*p) );
-      if( p ){
-#if SQLITE_MUTEX_NREF
-        p->id = iType;
+    if( isLookaside(db, p) ){
+      LookasideSlot *pBuf = (LookasideSlot*)p;
+#if SQLITE_DEBUG
+      /* Trash all content in the buffer being freed */
+      memset(p, 0xaa, db->lookaside.sz);
 #endif
-        rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
-      }
-      break;
-    }
-    default: {
-      assert( iType-2 >= 0 );
-      assert( iType-2 < ArraySize(staticMutexes) );
-      p = &staticMutexes[iType-2];
-#if SQLITE_MUTEX_NREF
-      p->id = iType;
-#endif
-      rt_mutex_init(&p->mutex, "sqlmtx", RT_IPC_FLAG_PRIO);
-      break;
+      pBuf->pNext = db->lookaside.pFree;
+      db->lookaside.pFree = pBuf;
+      db->lookaside.nOut--;
+      return;
     }
   }
-  return p;
-}
-
-
-/*
-** This routine deallocates a previously
-** allocated mutex.  SQLite is careful to deallocate every
-** mutex that it allocates.
-*/
-static void rttMutexFree(sqlite3_mutex *p){
-  assert( p->nRef==0 );
-  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
-  rt_mutex_delete(&p->mutex);
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
   sqlite3_free(p);
 }
 
 /*
-** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex.  If another thread is already within the mutex,
-** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
-** be entered multiple times by the same thread.  In such cases the,
-** mutex must be exited an equal number of times before another thread
-** can enter.  If the same thread tries to enter any other kind of mutex
-** more than once, the behavior is undefined.
+** Change the size of an existing memory allocation
 */
-static void rttMutexEnter(sqlite3_mutex *p){
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || rttMutexNotheld(p) );
-
-#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
-  /* If recursive mutexes are not available, then we have to grow
-  ** our own.  This implementation assumes that rtt_equal()
-  ** is atomic - that it cannot be deceived into thinking self
-  ** and p->owner are equal if p->owner changes between two values
-  ** that are not equal to self while the comparison is taking place.
-  ** This implementation also assumes a coherent cache - that
-  ** separate processes cannot read different values from the same
-  ** address at the same time.  If either of these two conditions
-  ** are not met, then the mutexes will fail and problems will result.
-  */
-  {
-    rt_thread_t self = rt_thread_self();
-    if( p->nRef>0 && (p->owner == self) ){
-      p->nRef++;
-    }else{
-      rt_mutex_take(&p->mutex, RT_WAITING_FOREVER);
-      assert( p->nRef==0 );
-      p->owner = self;
-      p->nRef = 1;
-    }
+SQLITE_PRIVATE void *sqlite3Realloc(void *pOld, int nBytes){
+  int nOld, nNew, nDiff;
+  void *pNew;
+  if( pOld==0 ){
+    return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
   }
-#else
-  /* Use the built-in recursive mutexes if they are available.
-  */
-  rt_mutex_take(&p->mutex, RT_WAITING_FOREVER);
-#if SQLITE_MUTEX_NREF
-  assert( p->nRef>0 || p->owner==0 );
-  p->owner = rt_thread_self();
-  p->nRef++;
-#endif
-#endif
-
-#ifdef SQLITE_DEBUG
-  if( p->trace ){
-    rt_kprintf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+  if( nBytes<=0 ){
+    sqlite3_free(pOld); /* IMP: R-31593-10574 */
+    return 0;
   }
-#endif
-}
-static int rttMutexTry(sqlite3_mutex *p){
-  int rc;
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || rttMutexNotheld(p) );
-
-#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
-  /* If recursive mutexes are not available, then we have to grow
-  ** our own.  This implementation assumes that rtt_equal()
-  ** is atomic - that it cannot be deceived into thinking self
-  ** and p->owner are equal if p->owner changes between two values
-  ** that are not equal to self while the comparison is taking place.
-  ** This implementation also assumes a coherent cache - that
-  ** separate processes cannot read different values from the same
-  ** address at the same time.  If either of these two conditions
-  ** are not met, then the mutexes will fail and problems will result.
-  */
-  {
-    rt_thread_t self = rt_thread_self();
-    if( p->nRef>0 && (p->owner == self) ){
-      p->nRef++;
-      rc = SQLITE_OK;
-    }else if( rt_mutex_take(&p->mutex, RT_WAITING_NO)==RT_EOK ){
-      assert( p->nRef==0 );
-      p->owner = self;
-      p->nRef = 1;
-      rc = SQLITE_OK;
-    }else{
-      rc = SQLITE_BUSY;
-    }
+  if( nBytes>=0x7fffff00 ){
+    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
+    return 0;
   }
-#else
-  /* Use the built-in recursive mutexes if they are available.
-  */
-  if( rt_mutex_take(&p->mutex, RT_WAITING_NO)==RT_EOK ){
-#if SQLITE_MUTEX_NREF
-    p->owner = rt_thread_self();
-    p->nRef++;
-#endif
-    rc = SQLITE_OK;
+  nOld = sqlite3MallocSize(pOld);
+  /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
+  ** argument to xRealloc is always a value returned by a prior call to
+  ** xRoundup. */
+  nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
+  if( nOld==nNew ){
+    pNew = pOld;
+  }else if( sqlite3GlobalConfig.bMemstat ){
+    sqlite3_mutex_enter(mem0.mutex);
+    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
+    nDiff = nNew - nOld;
+    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
+          mem0.alarmThreshold-nDiff ){
+      sqlite3MallocAlarm(nDiff);
+    }
+    assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
+    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+    if( pNew==0 && mem0.alarmCallback ){
+      sqlite3MallocAlarm(nBytes);
+      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+    }
+    if( pNew ){
+      nNew = sqlite3MallocSize(pNew);
+      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
+    }
+    sqlite3_mutex_leave(mem0.mutex);
   }else{
-    rc = SQLITE_BUSY;
-  }
-#endif
-
-#ifdef SQLITE_DEBUG
-  if( rc==SQLITE_OK && p->trace ){
-    rt_kprintf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
   }
-#endif
-  return rc;
+  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
+  return pNew;
 }
 
 /*
-** The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  The behavior
-** is undefined if the mutex is not currently entered or
-** is not currently allocated.  SQLite will never do either.
+** The public interface to sqlite3Realloc.  Make sure that the memory
+** subsystem is initialized prior to invoking sqliteRealloc.
 */
-static void rttMutexLeave(sqlite3_mutex *p){
-  assert( rttMutexHeld(p) );
-#if SQLITE_MUTEX_NREF
-  p->nRef--;
-  if( p->nRef==0 ) p->owner = 0;
+SQLITE_API void *sqlite3_realloc(void *pOld, int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
 #endif
-  assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
+  return sqlite3Realloc(pOld, n);
+}
 
-#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
-  if( p->nRef==0 ){
-    rt_mutex_release(&p->mutex);
-  }
-#else
-  rt_mutex_release(&p->mutex);
-#endif
 
-#ifdef SQLITE_DEBUG
-  if( p->trace ){
-    rt_kprintf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+/*
+** Allocate and zero memory.
+*/ 
+SQLITE_PRIVATE void *sqlite3MallocZero(int n){
+  void *p = sqlite3Malloc(n);
+  if( p ){
+    memset(p, 0, n);
   }
-#endif
+  return p;
 }
 
-SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
-  static const sqlite3_mutex_methods sMutex = {
-    rttMutexInit,
-    rttMutexEnd,
-    rttMutexAlloc,
-    rttMutexFree,
-    rttMutexEnter,
-    rttMutexTry,
-    rttMutexLeave,
-#ifdef SQLITE_DEBUG
-    rttMutexHeld,
-    rttMutexNotheld
-#else
-    0,
-    0
-#endif
-  };
-
-  return &sMutex;
+/*
+** Allocate and zero memory.  If the allocation fails, make
+** the mallocFailed flag in the connection pointer.
+*/
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, int n){
+  void *p = sqlite3DbMallocRaw(db, n);
+  if( p ){
+    memset(p, 0, n);
+  }
+  return p;
 }
 
-#endif /* SQLITE_MUTEX_RTT */
-
-
-/************** End of mutex_rtt.c *******************************************/
-/************** Begin file malloc.c ******************************************/
 /*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
+** Allocate and zero memory.  If the allocation fails, make
+** the mallocFailed flag in the connection pointer.
 **
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** If db!=0 and db->mallocFailed is true (indicating a prior malloc
+** failure on the same database connection) then always return 0.
+** Hence for a particular database connection, once malloc starts
+** failing, it fails consistently until mallocFailed is reset.
+** This is an important assumption.  There are many places in the
+** code that do things like this:
 **
-*************************************************************************
+**         int *a = (int*)sqlite3DbMallocRaw(db, 100);
+**         int *b = (int*)sqlite3DbMallocRaw(db, 200);
+**         if( b ) a[10] = 9;
 **
-** Memory allocation functions used throughout sqlite.
+** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
+** that all prior mallocs (ex: "a") worked too.
 */
-/* #include <stdarg.h> */
-
-/*
-** Attempt to release up to n bytes of non-essential memory currently
-** held by SQLite. An example of non-essential memory is memory used to
-** cache database pages that are not currently in use.
-*/
-SQLITE_API int sqlite3_release_memory(int n){
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  return sqlite3PcacheReleaseMemory(n);
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
+  void *p;
+  assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  assert( db==0 || db->pnBytesFreed==0 );
+#ifndef SQLITE_OMIT_LOOKASIDE
+  if( db ){
+    LookasideSlot *pBuf;
+    if( db->mallocFailed ){
+      return 0;
+    }
+    if( db->lookaside.bEnabled ){
+      if( n>db->lookaside.sz ){
+        db->lookaside.anStat[1]++;
+      }else if( (pBuf = db->lookaside.pFree)==0 ){
+        db->lookaside.anStat[2]++;
+      }else{
+        db->lookaside.pFree = pBuf->pNext;
+        db->lookaside.nOut++;
+        db->lookaside.anStat[0]++;
+        if( db->lookaside.nOut>db->lookaside.mxOut ){
+          db->lookaside.mxOut = db->lookaside.nOut;
+        }
+        return (void*)pBuf;
+      }
+    }
+  }
 #else
-  /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
-  ** is a no-op returning zero if SQLite is not compiled with
-  ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
-  UNUSED_PARAMETER(n);
-  return 0;
+  if( db && db->mallocFailed ){
+    return 0;
+  }
 #endif
+  p = sqlite3Malloc(n);
+  if( !p && db ){
+    db->mallocFailed = 1;
+  }
+  sqlite3MemdebugSetType(p, MEMTYPE_DB |
+         ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
+  return p;
 }
 
 /*
-** An instance of the following object records the location of
-** each unused scratch buffer.
-*/
-typedef struct ScratchFreeslot {
-  struct ScratchFreeslot *pNext;   /* Next unused scratch buffer */
-} ScratchFreeslot;
-
-/*
-** State information local to the memory allocation subsystem.
+** Resize the block of memory pointed to by p to n bytes. If the
+** resize fails, set the mallocFailed flag in the connection object.
 */
-static SQLITE_WSD struct Mem0Global {
-  sqlite3_mutex *mutex;         /* Mutex to serialize access */
-
-  /*
-  ** The alarm callback and its arguments.  The mem0.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.
-  */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64,int);
-  void *alarmArg;
-
-  /*
-  ** Pointers to the end of sqlite3GlobalConfig.pScratch memory
-  ** (so that a range test can be used to determine if an allocation
-  ** being freed came from pScratch) and a pointer to the list of
-  ** unused scratch allocations.
-  */
-  void *pScratchEnd;
-  ScratchFreeslot *pScratchFree;
-  u32 nScratchFree;
-
-  /*
-  ** True if heap is nearly "full" where "full" is defined by the
-  ** sqlite3_soft_heap_limit() setting.
-  */
-  int nearlyFull;
-} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
-
-#define mem0 GLOBAL(struct Mem0Global, mem0)
+SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *db, void *p, int n){
+  void *pNew = 0;
+  assert( db!=0 );
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( db->mallocFailed==0 ){
+    if( p==0 ){
+      return sqlite3DbMallocRaw(db, n);
+    }
+    if( isLookaside(db, p) ){
+      if( n<=db->lookaside.sz ){
+        return p;
+      }
+      pNew = sqlite3DbMallocRaw(db, n);
+      if( pNew ){
+        memcpy(pNew, p, db->lookaside.sz);
+        sqlite3DbFree(db, p);
+      }
+    }else{
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+      pNew = sqlite3_realloc(p, n);
+      if( !pNew ){
+        sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
+        db->mallocFailed = 1;
+      }
+      sqlite3MemdebugSetType(pNew, MEMTYPE_DB | 
+            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
+    }
+  }
+  return pNew;
+}
 
 /*
-** This routine runs when the memory allocator sees that the
-** total memory allocation is about to exceed the soft heap
-** limit.
+** Attempt to reallocate p.  If the reallocation fails, then free p
+** and set the mallocFailed flag in the database connection.
 */
-static void softHeapLimitEnforcer(
-  void *NotUsed, 
-  sqlite3_int64 NotUsed2,
-  int allocSize
-){
-  UNUSED_PARAMETER2(NotUsed, NotUsed2);
-  sqlite3_release_memory(allocSize);
+SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
+  void *pNew;
+  pNew = sqlite3DbRealloc(db, p, n);
+  if( !pNew ){
+    sqlite3DbFree(db, p);
+  }
+  return pNew;
 }
 
 /*
-** Change the alarm callback
+** Make a copy of a string in memory obtained from sqliteMalloc(). These 
+** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
+** is because when memory debugging is turned on, these two functions are 
+** called via macros that record the current file and line number in the
+** ThreadData structure.
 */
-static int sqlite3MemoryAlarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  int nUsed;
-  sqlite3_mutex_enter(mem0.mutex);
-  mem0.alarmCallback = xCallback;
-  mem0.alarmArg = pArg;
-  mem0.alarmThreshold = iThreshold;
-  nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
-  mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed);
-  sqlite3_mutex_leave(mem0.mutex);
-  return SQLITE_OK;
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
+  char *zNew;
+  size_t n;
+  if( z==0 ){
+    return 0;
+  }
+  n = sqlite3Strlen30(z) + 1;
+  assert( (n&0x7fffffff)==n );
+  zNew = sqlite3DbMallocRaw(db, (int)n);
+  if( zNew ){
+    memcpy(zNew, z, n);
+  }
+  return zNew;
+}
+SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, int n){
+  char *zNew;
+  if( z==0 ){
+    return 0;
+  }
+  assert( (n&0x7fffffff)==n );
+  zNew = sqlite3DbMallocRaw(db, n+1);
+  if( zNew ){
+    memcpy(zNew, z, n);
+    zNew[n] = 0;
+  }
+  return zNew;
 }
 
-#ifndef SQLITE_OMIT_DEPRECATED
 /*
-** Deprecated external interface.  Internal/core SQLite code
-** should call sqlite3MemoryAlarm.
+** Create a string from the zFromat argument and the va_list that follows.
+** Store the string in memory obtained from sqliteMalloc() and make *pz
+** point to that string.
 */
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
+SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zFormat, ...){
+  va_list ap;
+  char *z;
+
+  va_start(ap, zFormat);
+  z = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  sqlite3DbFree(db, *pz);
+  *pz = z;
 }
-#endif
+
 
 /*
-** Set the soft heap-size limit for the library. Passing a zero or 
-** negative value indicates no limit.
+** This function must be called before exiting any API function (i.e. 
+** returning control to the user) that has called sqlite3_malloc or
+** sqlite3_realloc.
+**
+** The returned value is normally a copy of the second argument to this
+** function. However, if a malloc() failure has occurred since the previous
+** invocation SQLITE_NOMEM is returned instead. 
+**
+** If the first argument, db, is not NULL and a malloc() error has occurred,
+** then the connection error-code (the value returned by sqlite3_errcode())
+** is set to SQLITE_NOMEM.
 */
-SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
-  sqlite3_int64 priorLimit;
-  sqlite3_int64 excess;
-#ifndef SQLITE_OMIT_AUTOINIT
-  int rc = sqlite3_initialize();
-  if( rc ) return -1;
-#endif
-  sqlite3_mutex_enter(mem0.mutex);
-  priorLimit = mem0.alarmThreshold;
-  sqlite3_mutex_leave(mem0.mutex);
-  if( n<0 ) return priorLimit;
-  if( n>0 ){
-    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n);
-  }else{
-    sqlite3MemoryAlarm(0, 0, 0);
+SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
+  /* If the db handle is not NULL, then we must hold the connection handle
+  ** mutex here. Otherwise the read (and possible write) of db->mallocFailed 
+  ** is unsafe, as is the call to sqlite3Error().
+  */
+  assert( !db || sqlite3_mutex_held(db->mutex) );
+  if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
+    sqlite3Error(db, SQLITE_NOMEM, 0);
+    db->mallocFailed = 0;
+    rc = SQLITE_NOMEM;
   }
-  excess = sqlite3_memory_used() - n;
-  if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff));
-  return priorLimit;
-}
-SQLITE_API void sqlite3_soft_heap_limit(int n){
-  if( n<0 ) n = 0;
-  sqlite3_soft_heap_limit64(n);
+  return rc & (db ? db->errMask : 0xff);
 }
 
+/************** End of malloc.c **********************************************/
+/************** Begin file printf.c ******************************************/
 /*
-** Initialize the memory allocation subsystem.
+** The "printf" code that follows dates from the 1980's.  It is in
+** the public domain.  The original comments are included here for
+** completeness.  They are very out-of-date but might be useful as
+** an historical reference.  Most of the "enhancements" have been backed
+** out so that the functionality is now the same as standard printf().
+**
+**************************************************************************
+**
+** This file contains code for a set of "printf"-like routines.  These
+** routines format strings much like the printf() from the standard C
+** library, though the implementation here has enhancements to support
+** SQLlite.
 */
-SQLITE_PRIVATE int sqlite3MallocInit(void){
-  if( sqlite3GlobalConfig.m.xMalloc==0 ){
-    sqlite3MemSetDefault();
-  }
-  memset(&mem0, 0, sizeof(mem0));
-  if( sqlite3GlobalConfig.bCoreMutex ){
-    mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
-  }
-  if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
-      && sqlite3GlobalConfig.nScratch>0 ){
-    int i, n, sz;
-    ScratchFreeslot *pSlot;
-    sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
-    sqlite3GlobalConfig.szScratch = sz;
-    pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;
-    n = sqlite3GlobalConfig.nScratch;
-    mem0.pScratchFree = pSlot;
-    mem0.nScratchFree = n;
-    for(i=0; i<n-1; i++){
-      pSlot->pNext = (ScratchFreeslot*)(sz+(char*)pSlot);
-      pSlot = pSlot->pNext;
-    }
-    pSlot->pNext = 0;
-    mem0.pScratchEnd = (void*)&pSlot[1];
-  }else{
-    mem0.pScratchEnd = 0;
-    sqlite3GlobalConfig.pScratch = 0;
-    sqlite3GlobalConfig.szScratch = 0;
-    sqlite3GlobalConfig.nScratch = 0;
-  }
-  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
-      || sqlite3GlobalConfig.nPage<1 ){
-    sqlite3GlobalConfig.pPage = 0;
-    sqlite3GlobalConfig.szPage = 0;
-    sqlite3GlobalConfig.nPage = 0;
-  }
-  return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
-}
 
 /*
-** Return true if the heap is currently under memory pressure - in other
-** words if the amount of heap used is close to the limit set by
-** sqlite3_soft_heap_limit().
+** Conversion types fall into various categories as defined by the
+** following enumeration.
 */
-SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
-  return mem0.nearlyFull;
-}
+#define etRADIX       1 /* Integer types.  %d, %x, %o, and so forth */
+#define etFLOAT       2 /* Floating point.  %f */
+#define etEXP         3 /* Exponentional notation. %e and %E */
+#define etGENERIC     4 /* Floating or exponential, depending on exponent. %g */
+#define etSIZE        5 /* Return number of characters processed so far. %n */
+#define etSTRING      6 /* Strings. %s */
+#define etDYNSTRING   7 /* Dynamically allocated strings. %z */
+#define etPERCENT     8 /* Percent symbol. %% */
+#define etCHARX       9 /* Characters. %c */
+/* The rest are extensions, not normally found in printf() */
+#define etSQLESCAPE  10 /* Strings with '\'' doubled.  %q */
+#define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
+                          NULL pointers replaced by SQL NULL.  %Q */
+#define etTOKEN      12 /* a pointer to a Token structure */
+#define etSRCLIST    13 /* a pointer to a SrcList */
+#define etPOINTER    14 /* The %p conversion */
+#define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
+#define etORDINAL    16 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
+
+#define etINVALID     0 /* Any unrecognized conversion type */
+
 
 /*
-** Deinitialize the memory allocation subsystem.
+** An "etByte" is an 8-bit unsigned value.
 */
-SQLITE_PRIVATE void sqlite3MallocEnd(void){
-  if( sqlite3GlobalConfig.m.xShutdown ){
-    sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData);
-  }
-  memset(&mem0, 0, sizeof(mem0));
-}
+typedef unsigned char etByte;
 
 /*
-** Return the amount of memory currently checked out.
+** Each builtin conversion character (ex: the 'd' in "%d") is described
+** by an instance of the following structure
 */
-SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
-  int n, mx;
-  sqlite3_int64 res;
-  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, 0);
-  res = (sqlite3_int64)n;  /* Work around bug in Borland C. Ticket #3216 */
-  return res;
-}
+typedef struct et_info {   /* Information about each format field */
+  char fmttype;            /* The format field code letter */
+  etByte base;             /* The base for radix conversion */
+  etByte flags;            /* One or more of FLAG_ constants below */
+  etByte type;             /* Conversion paradigm */
+  etByte charset;          /* Offset into aDigits[] of the digits string */
+  etByte prefix;           /* Offset into aPrefix[] of the prefix string */
+} et_info;
 
 /*
-** Return the maximum amount of memory that has ever been
-** checked out since either the beginning of this process
-** or since the most recent reset.
+** Allowed values for et_info.flags
 */
-SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
-  int n, mx;
-  sqlite3_int64 res;
-  sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, resetFlag);
-  res = (sqlite3_int64)mx;  /* Work around bug in Borland C. Ticket #3216 */
-  return res;
-}
+#define FLAG_SIGNED  1     /* True if the value to convert is signed */
+#define FLAG_INTERN  2     /* True if for internal use only */
+#define FLAG_STRING  4     /* Allow infinity precision */
+
 
 /*
-** Trigger the alarm 
+** The following table is searched linearly, so it is good to put the
+** most frequently used conversion types first.
 */
-static void sqlite3MallocAlarm(int nByte){
-  void (*xCallback)(void*,sqlite3_int64,int);
-  sqlite3_int64 nowUsed;
-  void *pArg;
-  if( mem0.alarmCallback==0 ) return;
-  xCallback = mem0.alarmCallback;
-  nowUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
-  pArg = mem0.alarmArg;
-  mem0.alarmCallback = 0;
-  sqlite3_mutex_leave(mem0.mutex);
-  xCallback(pArg, nowUsed, nByte);
-  sqlite3_mutex_enter(mem0.mutex);
-  mem0.alarmCallback = xCallback;
-  mem0.alarmArg = pArg;
+static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
+static const char aPrefix[] = "-x0\000X0";
+static const et_info fmtinfo[] = {
+  {  'd', 10, 1, etRADIX,      0,  0 },
+  {  's',  0, 4, etSTRING,     0,  0 },
+  {  'g',  0, 1, etGENERIC,    30, 0 },
+  {  'z',  0, 4, etDYNSTRING,  0,  0 },
+  {  'q',  0, 4, etSQLESCAPE,  0,  0 },
+  {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
+  {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
+  {  'c',  0, 0, etCHARX,      0,  0 },
+  {  'o',  8, 0, etRADIX,      0,  2 },
+  {  'u', 10, 0, etRADIX,      0,  0 },
+  {  'x', 16, 0, etRADIX,      16, 1 },
+  {  'X', 16, 0, etRADIX,      0,  4 },
+#ifndef SQLITE_OMIT_FLOATING_POINT
+  {  'f',  0, 1, etFLOAT,      0,  0 },
+  {  'e',  0, 1, etEXP,        30, 0 },
+  {  'E',  0, 1, etEXP,        14, 0 },
+  {  'G',  0, 1, etGENERIC,    14, 0 },
+#endif
+  {  'i', 10, 1, etRADIX,      0,  0 },
+  {  'n',  0, 0, etSIZE,       0,  0 },
+  {  '%',  0, 0, etPERCENT,    0,  0 },
+  {  'p', 16, 0, etPOINTER,    0,  1 },
+
+/* All the rest have the FLAG_INTERN bit set and are thus for internal
+** use only */
+  {  'T',  0, 2, etTOKEN,      0,  0 },
+  {  'S',  0, 2, etSRCLIST,    0,  0 },
+  {  'r', 10, 3, etORDINAL,    0,  0 },
+};
+
+/*
+** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
+** conversions will work.
+*/
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** "*val" is a double such that 0.1 <= *val < 10.0
+** Return the ascii code for the leading digit of *val, then
+** multiply "*val" by 10.0 to renormalize.
+**
+** Example:
+**     input:     *val = 3.14159
+**     output:    *val = 1.4159    function return = '3'
+**
+** The counter *cnt is incremented each time.  After counter exceeds
+** 16 (the number of significant digits in a 64-bit float) '0' is
+** always returned.
+*/
+static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
+  int digit;
+  LONGDOUBLE_TYPE d;
+  if( (*cnt)<=0 ) return '0';
+  (*cnt)--;
+  digit = (int)*val;
+  d = digit;
+  digit += '0';
+  *val = (*val - d)*10.0;
+  return (char)digit;
 }
+#endif /* SQLITE_OMIT_FLOATING_POINT */
 
 /*
-** Do a memory allocation with statistics and alarms.  Assume the
-** lock is already held.
+** Append N space characters to the given string buffer.
 */
-static int mallocWithAlarm(int n, void **pp){
-  int nFull;
-  void *p;
-  assert( sqlite3_mutex_held(mem0.mutex) );
-  nFull = sqlite3GlobalConfig.m.xRoundup(n);
-  sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n);
-  if( mem0.alarmCallback!=0 ){
-    int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
-    if( nUsed >= mem0.alarmThreshold - nFull ){
-      mem0.nearlyFull = 1;
-      sqlite3MallocAlarm(nFull);
-    }else{
-      mem0.nearlyFull = 0;
-    }
-  }
-  p = sqlite3GlobalConfig.m.xMalloc(nFull);
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  if( p==0 && mem0.alarmCallback ){
-    sqlite3MallocAlarm(nFull);
-    p = sqlite3GlobalConfig.m.xMalloc(nFull);
+SQLITE_PRIVATE void sqlite3AppendSpace(StrAccum *pAccum, int N){
+  static const char zSpaces[] = "                             ";
+  while( N>=(int)sizeof(zSpaces)-1 ){
+    sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
+    N -= sizeof(zSpaces)-1;
   }
-#endif
-  if( p ){
-    nFull = sqlite3MallocSize(p);
-    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
-    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1);
+  if( N>0 ){
+    sqlite3StrAccumAppend(pAccum, zSpaces, N);
   }
-  *pp = p;
-  return nFull;
 }
 
 /*
-** Allocate memory.  This routine is like sqlite3_malloc() except that it
-** assumes the memory subsystem has already been initialized.
+** On machines with a small stack size, you can redefine the
+** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
 */
-SQLITE_PRIVATE void *sqlite3Malloc(int n){
-  void *p;
-  if( n<=0               /* IMP: R-65312-04917 */ 
-   || n>=0x7fffff00
-  ){
-    /* A memory allocation of a number of bytes which is near the maximum
-    ** signed integer value might cause an integer overflow inside of the
-    ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
-    ** 255 bytes of overhead.  SQLite itself will never use anything near
-    ** this amount.  The only way to reach the limit is with sqlite3_malloc() */
-    p = 0;
-  }else if( sqlite3GlobalConfig.bMemstat ){
-    sqlite3_mutex_enter(mem0.mutex);
-    mallocWithAlarm(n, &p);
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    p = sqlite3GlobalConfig.m.xMalloc(n);
-  }
-  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-04675-44850 */
-  return p;
-}
-
-/*
-** This version of the memory allocation is for use by the application.
-** First make sure the memory subsystem is initialized, then do the
-** allocation.
-*/
-SQLITE_API void *sqlite3_malloc(int n){
-#ifndef SQLITE_OMIT_AUTOINIT
-  if( sqlite3_initialize() ) return 0;
+#ifndef SQLITE_PRINT_BUF_SIZE
+# define SQLITE_PRINT_BUF_SIZE 70
 #endif
-  return sqlite3Malloc(n);
-}
+#define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
 
 /*
-** Each thread may only have a single outstanding allocation from
-** xScratchMalloc().  We verify this constraint in the single-threaded
-** case by setting scratchAllocOut to 1 when an allocation
-** is outstanding clearing it when the allocation is freed.
+** Render a string given by "fmt" into the StrAccum object.
 */
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-static int scratchAllocOut = 0;
+SQLITE_PRIVATE void sqlite3VXPrintf(
+  StrAccum *pAccum,                  /* Accumulate results here */
+  int useExtended,                   /* Allow extended %-conversions */
+  const char *fmt,                   /* Format string */
+  va_list ap                         /* arguments */
+){
+  int c;                     /* Next character in the format string */
+  char *bufpt;               /* Pointer to the conversion buffer */
+  int precision;             /* Precision of the current field */
+  int length;                /* Length of the field */
+  int idx;                   /* A general purpose loop counter */
+  int width;                 /* Width of the current field */
+  etByte flag_leftjustify;   /* True if "-" flag is present */
+  etByte flag_plussign;      /* True if "+" flag is present */
+  etByte flag_blanksign;     /* True if " " flag is present */
+  etByte flag_alternateform; /* True if "#" flag is present */
+  etByte flag_altform2;      /* True if "!" flag is present */
+  etByte flag_zeropad;       /* True if field width constant starts with zero */
+  etByte flag_long;          /* True if "l" flag is present */
+  etByte flag_longlong;      /* True if the "ll" flag is present */
+  etByte done;               /* Loop termination flag */
+  etByte xtype = 0;          /* Conversion paradigm */
+  char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
+  sqlite_uint64 longvalue;   /* Value for integer types */
+  LONGDOUBLE_TYPE realvalue; /* Value for real types */
+  const et_info *infop;      /* Pointer to the appropriate info structure */
+  char *zOut;                /* Rendering buffer */
+  int nOut;                  /* Size of the rendering buffer */
+  char *zExtra;              /* Malloced memory used by some conversion */
+#ifndef SQLITE_OMIT_FLOATING_POINT
+  int  exp, e2;              /* exponent of real numbers */
+  int nsd;                   /* Number of significant digits returned */
+  double rounder;            /* Used for rounding floating point values */
+  etByte flag_dp;            /* True if decimal point should be shown */
+  etByte flag_rtz;           /* True if trailing zeros should be removed */
 #endif
+  char buf[etBUFSIZE];       /* Conversion buffer */
 
-
-/*
-** Allocate memory that is to be used and released right away.
-** This routine is similar to alloca() in that it is not intended
-** for situations where the memory might be held long-term.  This
-** routine is intended to get memory to old large transient data
-** structures that would not normally fit on the stack of an
-** embedded processor.
-*/
-SQLITE_PRIVATE void *sqlite3ScratchMalloc(int n){
-  void *p;
-  assert( n>0 );
-
-  sqlite3_mutex_enter(mem0.mutex);
-  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
-    p = mem0.pScratchFree;
-    mem0.pScratchFree = mem0.pScratchFree->pNext;
-    mem0.nScratchFree--;
-    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
-    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    if( sqlite3GlobalConfig.bMemstat ){
-      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-      n = mallocWithAlarm(n, &p);
-      if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
-      sqlite3_mutex_leave(mem0.mutex);
+  bufpt = 0;
+  for(; (c=(*fmt))!=0; ++fmt){
+    if( c!='%' ){
+      int amt;
+      bufpt = (char *)fmt;
+      amt = 1;
+      while( (c=(*++fmt))!='%' && c!=0 ) amt++;
+      sqlite3StrAccumAppend(pAccum, bufpt, amt);
+      if( c==0 ) break;
+    }
+    if( (c=(*++fmt))==0 ){
+      sqlite3StrAccumAppend(pAccum, "%", 1);
+      break;
+    }
+    /* Find out what flags are present */
+    flag_leftjustify = flag_plussign = flag_blanksign = 
+     flag_alternateform = flag_altform2 = flag_zeropad = 0;
+    done = 0;
+    do{
+      switch( c ){
+        case '-':   flag_leftjustify = 1;     break;
+        case '+':   flag_plussign = 1;        break;
+        case ' ':   flag_blanksign = 1;       break;
+        case '#':   flag_alternateform = 1;   break;
+        case '!':   flag_altform2 = 1;        break;
+        case '0':   flag_zeropad = 1;         break;
+        default:    done = 1;                 break;
+      }
+    }while( !done && (c=(*++fmt))!=0 );
+    /* Get the field width */
+    width = 0;
+    if( c=='*' ){
+      width = va_arg(ap,int);
+      if( width<0 ){
+        flag_leftjustify = 1;
+        width = -width;
+      }
+      c = *++fmt;
     }else{
-      sqlite3_mutex_leave(mem0.mutex);
-      p = sqlite3GlobalConfig.m.xMalloc(n);
+      while( c>='0' && c<='9' ){
+        width = width*10 + c - '0';
+        c = *++fmt;
+      }
     }
-    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
-  }
-  assert( sqlite3_mutex_notheld(mem0.mutex) );
-
-
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  /* Verify that no more than two scratch allocations per thread
-  ** are outstanding at one time.  (This is only checked in the
-  ** single-threaded case since checking in the multi-threaded case
-  ** would be much more complicated.) */
-  assert( scratchAllocOut<=1 );
-  if( p ) scratchAllocOut++;
-#endif
-
-  return p;
-}
-SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
-  if( p ){
-
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-    /* Verify that no more than two scratch allocation per thread
-    ** is outstanding at one time.  (This is only checked in the
-    ** single-threaded case since checking in the multi-threaded case
-    ** would be much more complicated.) */
-    assert( scratchAllocOut>=1 && scratchAllocOut<=2 );
-    scratchAllocOut--;
-#endif
-
-    if( p>=sqlite3GlobalConfig.pScratch && p<mem0.pScratchEnd ){
-      /* Release memory from the SQLITE_CONFIG_SCRATCH allocation */
-      ScratchFreeslot *pSlot;
-      pSlot = (ScratchFreeslot*)p;
-      sqlite3_mutex_enter(mem0.mutex);
-      pSlot->pNext = mem0.pScratchFree;
-      mem0.pScratchFree = pSlot;
-      mem0.nScratchFree++;
-      assert( mem0.nScratchFree <= (u32)sqlite3GlobalConfig.nScratch );
-      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
-      sqlite3_mutex_leave(mem0.mutex);
+    /* Get the precision */
+    if( c=='.' ){
+      precision = 0;
+      c = *++fmt;
+      if( c=='*' ){
+        precision = va_arg(ap,int);
+        if( precision<0 ) precision = -precision;
+        c = *++fmt;
+      }else{
+        while( c>='0' && c<='9' ){
+          precision = precision*10 + c - '0';
+          c = *++fmt;
+        }
+      }
     }else{
-      /* Release memory back to the heap */
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
-      assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) );
-      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-      if( sqlite3GlobalConfig.bMemstat ){
-        int iSize = sqlite3MallocSize(p);
-        sqlite3_mutex_enter(mem0.mutex);
-        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
-        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
-        sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
-        sqlite3GlobalConfig.m.xFree(p);
-        sqlite3_mutex_leave(mem0.mutex);
+      precision = -1;
+    }
+    /* Get the conversion type modifier */
+    if( c=='l' ){
+      flag_long = 1;
+      c = *++fmt;
+      if( c=='l' ){
+        flag_longlong = 1;
+        c = *++fmt;
       }else{
-        sqlite3GlobalConfig.m.xFree(p);
+        flag_longlong = 0;
       }
+    }else{
+      flag_long = flag_longlong = 0;
     }
-  }
-}
-
-/*
-** TRUE if p is a lookaside memory allocation from db
-*/
-#ifndef SQLITE_OMIT_LOOKASIDE
-static int isLookaside(sqlite3 *db, void *p){
-  return p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
-}
-#else
-#define isLookaside(A,B) 0
-#endif
+    /* Fetch the info entry for the field */
+    infop = &fmtinfo[0];
+    xtype = etINVALID;
+    for(idx=0; idx<ArraySize(fmtinfo); idx++){
+      if( c==fmtinfo[idx].fmttype ){
+        infop = &fmtinfo[idx];
+        if( useExtended || (infop->flags & FLAG_INTERN)==0 ){
+          xtype = infop->type;
+        }else{
+          return;
+        }
+        break;
+      }
+    }
+    zExtra = 0;
 
-/*
-** Return the size of a memory allocation previously obtained from
-** sqlite3Malloc() or sqlite3_malloc().
-*/
-SQLITE_PRIVATE int sqlite3MallocSize(void *p){
-  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
-  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
-  return sqlite3GlobalConfig.m.xSize(p);
-}
-SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
-  assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( db && isLookaside(db, p) ){
-    return db->lookaside.sz;
-  }else{
-    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
-    assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
-    assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
-    return sqlite3GlobalConfig.m.xSize(p);
-  }
-}
-
-/*
-** Free memory previously obtained from sqlite3Malloc().
-*/
-SQLITE_API void sqlite3_free(void *p){
-  if( p==0 ) return;  /* IMP: R-49053-54554 */
-  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
-  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
-  if( sqlite3GlobalConfig.bMemstat ){
-    sqlite3_mutex_enter(mem0.mutex);
-    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
-    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
-    sqlite3GlobalConfig.m.xFree(p);
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    sqlite3GlobalConfig.m.xFree(p);
-  }
-}
-
-/*
-** Free memory that might be associated with a particular database
-** connection.
-*/
-SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
-  assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( p==0 ) return;
-  if( db ){
-    if( db->pnBytesFreed ){
-      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
-      return;
-    }
-    if( isLookaside(db, p) ){
-      LookasideSlot *pBuf = (LookasideSlot*)p;
-#if SQLITE_DEBUG
-      /* Trash all content in the buffer being freed */
-      memset(p, 0xaa, db->lookaside.sz);
-#endif
-      pBuf->pNext = db->lookaside.pFree;
-      db->lookaside.pFree = pBuf;
-      db->lookaside.nOut--;
-      return;
-    }
-  }
-  assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
-  assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
-  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
-  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-  sqlite3_free(p);
-}
-
-/*
-** Change the size of an existing memory allocation
-*/
-SQLITE_PRIVATE void *sqlite3Realloc(void *pOld, int nBytes){
-  int nOld, nNew, nDiff;
-  void *pNew;
-  if( pOld==0 ){
-    return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
-  }
-  if( nBytes<=0 ){
-    sqlite3_free(pOld); /* IMP: R-31593-10574 */
-    return 0;
-  }
-  if( nBytes>=0x7fffff00 ){
-    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
-    return 0;
-  }
-  nOld = sqlite3MallocSize(pOld);
-  /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
-  ** argument to xRealloc is always a value returned by a prior call to
-  ** xRoundup. */
-  nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
-  if( nOld==nNew ){
-    pNew = pOld;
-  }else if( sqlite3GlobalConfig.bMemstat ){
-    sqlite3_mutex_enter(mem0.mutex);
-    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
-    nDiff = nNew - nOld;
-    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
-          mem0.alarmThreshold-nDiff ){
-      sqlite3MallocAlarm(nDiff);
-    }
-    assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
-    assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
-    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
-    if( pNew==0 && mem0.alarmCallback ){
-      sqlite3MallocAlarm(nBytes);
-      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
-    }
-    if( pNew ){
-      nNew = sqlite3MallocSize(pNew);
-      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
-    }
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
-  }
-  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
-  return pNew;
-}
-
-/*
-** The public interface to sqlite3Realloc.  Make sure that the memory
-** subsystem is initialized prior to invoking sqliteRealloc.
-*/
-SQLITE_API void *sqlite3_realloc(void *pOld, int n){
-#ifndef SQLITE_OMIT_AUTOINIT
-  if( sqlite3_initialize() ) return 0;
-#endif
-  return sqlite3Realloc(pOld, n);
-}
-
-
-/*
-** Allocate and zero memory.
-*/ 
-SQLITE_PRIVATE void *sqlite3MallocZero(int n){
-  void *p = sqlite3Malloc(n);
-  if( p ){
-    memset(p, 0, n);
-  }
-  return p;
-}
-
-/*
-** Allocate and zero memory.  If the allocation fails, make
-** the mallocFailed flag in the connection pointer.
-*/
-SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, int n){
-  void *p = sqlite3DbMallocRaw(db, n);
-  if( p ){
-    memset(p, 0, n);
-  }
-  return p;
-}
-
-/*
-** Allocate and zero memory.  If the allocation fails, make
-** the mallocFailed flag in the connection pointer.
-**
-** If db!=0 and db->mallocFailed is true (indicating a prior malloc
-** failure on the same database connection) then always return 0.
-** Hence for a particular database connection, once malloc starts
-** failing, it fails consistently until mallocFailed is reset.
-** This is an important assumption.  There are many places in the
-** code that do things like this:
-**
-**         int *a = (int*)sqlite3DbMallocRaw(db, 100);
-**         int *b = (int*)sqlite3DbMallocRaw(db, 200);
-**         if( b ) a[10] = 9;
-**
-** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
-** that all prior mallocs (ex: "a") worked too.
-*/
-SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
-  void *p;
-  assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  assert( db==0 || db->pnBytesFreed==0 );
-#ifndef SQLITE_OMIT_LOOKASIDE
-  if( db ){
-    LookasideSlot *pBuf;
-    if( db->mallocFailed ){
-      return 0;
-    }
-    if( db->lookaside.bEnabled ){
-      if( n>db->lookaside.sz ){
-        db->lookaside.anStat[1]++;
-      }else if( (pBuf = db->lookaside.pFree)==0 ){
-        db->lookaside.anStat[2]++;
-      }else{
-        db->lookaside.pFree = pBuf->pNext;
-        db->lookaside.nOut++;
-        db->lookaside.anStat[0]++;
-        if( db->lookaside.nOut>db->lookaside.mxOut ){
-          db->lookaside.mxOut = db->lookaside.nOut;
-        }
-        return (void*)pBuf;
-      }
-    }
-  }
-#else
-  if( db && db->mallocFailed ){
-    return 0;
-  }
-#endif
-  p = sqlite3Malloc(n);
-  if( !p && db ){
-    db->mallocFailed = 1;
-  }
-  sqlite3MemdebugSetType(p, MEMTYPE_DB |
-         ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
-  return p;
-}
-
-/*
-** Resize the block of memory pointed to by p to n bytes. If the
-** resize fails, set the mallocFailed flag in the connection object.
-*/
-SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *db, void *p, int n){
-  void *pNew = 0;
-  assert( db!=0 );
-  assert( sqlite3_mutex_held(db->mutex) );
-  if( db->mallocFailed==0 ){
-    if( p==0 ){
-      return sqlite3DbMallocRaw(db, n);
-    }
-    if( isLookaside(db, p) ){
-      if( n<=db->lookaside.sz ){
-        return p;
-      }
-      pNew = sqlite3DbMallocRaw(db, n);
-      if( pNew ){
-        memcpy(pNew, p, db->lookaside.sz);
-        sqlite3DbFree(db, p);
-      }
-    }else{
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
-      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-      pNew = sqlite3_realloc(p, n);
-      if( !pNew ){
-        sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
-        db->mallocFailed = 1;
-      }
-      sqlite3MemdebugSetType(pNew, MEMTYPE_DB | 
-            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
-    }
-  }
-  return pNew;
-}
-
-/*
-** Attempt to reallocate p.  If the reallocation fails, then free p
-** and set the mallocFailed flag in the database connection.
-*/
-SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
-  void *pNew;
-  pNew = sqlite3DbRealloc(db, p, n);
-  if( !pNew ){
-    sqlite3DbFree(db, p);
-  }
-  return pNew;
-}
-
-/*
-** Make a copy of a string in memory obtained from sqliteMalloc(). These 
-** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
-** is because when memory debugging is turned on, these two functions are 
-** called via macros that record the current file and line number in the
-** ThreadData structure.
-*/
-SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
-  char *zNew;
-  size_t n;
-  if( z==0 ){
-    return 0;
-  }
-  n = sqlite3Strlen30(z) + 1;
-  assert( (n&0x7fffffff)==n );
-  zNew = sqlite3DbMallocRaw(db, (int)n);
-  if( zNew ){
-    memcpy(zNew, z, n);
-  }
-  return zNew;
-}
-SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, int n){
-  char *zNew;
-  if( z==0 ){
-    return 0;
-  }
-  assert( (n&0x7fffffff)==n );
-  zNew = sqlite3DbMallocRaw(db, n+1);
-  if( zNew ){
-    memcpy(zNew, z, n);
-    zNew[n] = 0;
-  }
-  return zNew;
-}
-
-/*
-** Create a string from the zFromat argument and the va_list that follows.
-** Store the string in memory obtained from sqliteMalloc() and make *pz
-** point to that string.
-*/
-SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zFormat, ...){
-  va_list ap;
-  char *z;
-
-  va_start(ap, zFormat);
-  z = sqlite3VMPrintf(db, zFormat, ap);
-  va_end(ap);
-  sqlite3DbFree(db, *pz);
-  *pz = z;
-}
-
-
-/*
-** This function must be called before exiting any API function (i.e. 
-** returning control to the user) that has called sqlite3_malloc or
-** sqlite3_realloc.
-**
-** The returned value is normally a copy of the second argument to this
-** function. However, if a malloc() failure has occurred since the previous
-** invocation SQLITE_NOMEM is returned instead. 
-**
-** If the first argument, db, is not NULL and a malloc() error has occurred,
-** then the connection error-code (the value returned by sqlite3_errcode())
-** is set to SQLITE_NOMEM.
-*/
-SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
-  /* If the db handle is not NULL, then we must hold the connection handle
-  ** mutex here. Otherwise the read (and possible write) of db->mallocFailed 
-  ** is unsafe, as is the call to sqlite3Error().
-  */
-  assert( !db || sqlite3_mutex_held(db->mutex) );
-  if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
-    sqlite3Error(db, SQLITE_NOMEM, 0);
-    db->mallocFailed = 0;
-    rc = SQLITE_NOMEM;
-  }
-  return rc & (db ? db->errMask : 0xff);
-}
-
-/************** End of malloc.c **********************************************/
-/************** Begin file printf.c ******************************************/
-/*
-** The "printf" code that follows dates from the 1980's.  It is in
-** the public domain.  The original comments are included here for
-** completeness.  They are very out-of-date but might be useful as
-** an historical reference.  Most of the "enhancements" have been backed
-** out so that the functionality is now the same as standard printf().
-**
-**************************************************************************
-**
-** This file contains code for a set of "printf"-like routines.  These
-** routines format strings much like the printf() from the standard C
-** library, though the implementation here has enhancements to support
-** SQLlite.
-*/
-
-/*
-** Conversion types fall into various categories as defined by the
-** following enumeration.
-*/
-#define etRADIX       1 /* Integer types.  %d, %x, %o, and so forth */
-#define etFLOAT       2 /* Floating point.  %f */
-#define etEXP         3 /* Exponentional notation. %e and %E */
-#define etGENERIC     4 /* Floating or exponential, depending on exponent. %g */
-#define etSIZE        5 /* Return number of characters processed so far. %n */
-#define etSTRING      6 /* Strings. %s */
-#define etDYNSTRING   7 /* Dynamically allocated strings. %z */
-#define etPERCENT     8 /* Percent symbol. %% */
-#define etCHARX       9 /* Characters. %c */
-/* The rest are extensions, not normally found in printf() */
-#define etSQLESCAPE  10 /* Strings with '\'' doubled.  %q */
-#define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
-                          NULL pointers replaced by SQL NULL.  %Q */
-#define etTOKEN      12 /* a pointer to a Token structure */
-#define etSRCLIST    13 /* a pointer to a SrcList */
-#define etPOINTER    14 /* The %p conversion */
-#define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
-#define etORDINAL    16 /* %r -> 1st, 2nd, 3rd, 4th, etc.  English only */
-
-#define etINVALID     0 /* Any unrecognized conversion type */
-
-
-/*
-** An "etByte" is an 8-bit unsigned value.
-*/
-typedef unsigned char etByte;
-
-/*
-** Each builtin conversion character (ex: the 'd' in "%d") is described
-** by an instance of the following structure
-*/
-typedef struct et_info {   /* Information about each format field */
-  char fmttype;            /* The format field code letter */
-  etByte base;             /* The base for radix conversion */
-  etByte flags;            /* One or more of FLAG_ constants below */
-  etByte type;             /* Conversion paradigm */
-  etByte charset;          /* Offset into aDigits[] of the digits string */
-  etByte prefix;           /* Offset into aPrefix[] of the prefix string */
-} et_info;
-
-/*
-** Allowed values for et_info.flags
-*/
-#define FLAG_SIGNED  1     /* True if the value to convert is signed */
-#define FLAG_INTERN  2     /* True if for internal use only */
-#define FLAG_STRING  4     /* Allow infinity precision */
-
-
-/*
-** The following table is searched linearly, so it is good to put the
-** most frequently used conversion types first.
-*/
-static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
-static const char aPrefix[] = "-x0\000X0";
-static const et_info fmtinfo[] = {
-  {  'd', 10, 1, etRADIX,      0,  0 },
-  {  's',  0, 4, etSTRING,     0,  0 },
-  {  'g',  0, 1, etGENERIC,    30, 0 },
-  {  'z',  0, 4, etDYNSTRING,  0,  0 },
-  {  'q',  0, 4, etSQLESCAPE,  0,  0 },
-  {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
-  {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
-  {  'c',  0, 0, etCHARX,      0,  0 },
-  {  'o',  8, 0, etRADIX,      0,  2 },
-  {  'u', 10, 0, etRADIX,      0,  0 },
-  {  'x', 16, 0, etRADIX,      16, 1 },
-  {  'X', 16, 0, etRADIX,      0,  4 },
-#ifndef SQLITE_OMIT_FLOATING_POINT
-  {  'f',  0, 1, etFLOAT,      0,  0 },
-  {  'e',  0, 1, etEXP,        30, 0 },
-  {  'E',  0, 1, etEXP,        14, 0 },
-  {  'G',  0, 1, etGENERIC,    14, 0 },
-#endif
-  {  'i', 10, 1, etRADIX,      0,  0 },
-  {  'n',  0, 0, etSIZE,       0,  0 },
-  {  '%',  0, 0, etPERCENT,    0,  0 },
-  {  'p', 16, 0, etPOINTER,    0,  1 },
-
-/* All the rest have the FLAG_INTERN bit set and are thus for internal
-** use only */
-  {  'T',  0, 2, etTOKEN,      0,  0 },
-  {  'S',  0, 2, etSRCLIST,    0,  0 },
-  {  'r', 10, 3, etORDINAL,    0,  0 },
-};
-
-/*
-** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
-** conversions will work.
-*/
-#ifndef SQLITE_OMIT_FLOATING_POINT
-/*
-** "*val" is a double such that 0.1 <= *val < 10.0
-** Return the ascii code for the leading digit of *val, then
-** multiply "*val" by 10.0 to renormalize.
-**
-** Example:
-**     input:     *val = 3.14159
-**     output:    *val = 1.4159    function return = '3'
-**
-** The counter *cnt is incremented each time.  After counter exceeds
-** 16 (the number of significant digits in a 64-bit float) '0' is
-** always returned.
-*/
-static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
-  int digit;
-  LONGDOUBLE_TYPE d;
-  if( (*cnt)<=0 ) return '0';
-  (*cnt)--;
-  digit = (int)*val;
-  d = digit;
-  digit += '0';
-  *val = (*val - d)*10.0;
-  return (char)digit;
-}
-#endif /* SQLITE_OMIT_FLOATING_POINT */
-
-/*
-** Append N space characters to the given string buffer.
-*/
-SQLITE_PRIVATE void sqlite3AppendSpace(StrAccum *pAccum, int N){
-  static const char zSpaces[] = "                             ";
-  while( N>=(int)sizeof(zSpaces)-1 ){
-    sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
-    N -= sizeof(zSpaces)-1;
-  }
-  if( N>0 ){
-    sqlite3StrAccumAppend(pAccum, zSpaces, N);
-  }
-}
-
-/*
-** On machines with a small stack size, you can redefine the
-** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
-*/
-#ifndef SQLITE_PRINT_BUF_SIZE
-# define SQLITE_PRINT_BUF_SIZE 70
-#endif
-#define etBUFSIZE SQLITE_PRINT_BUF_SIZE  /* Size of the output buffer */
-
-/*
-** Render a string given by "fmt" into the StrAccum object.
-*/
-SQLITE_PRIVATE void sqlite3VXPrintf(
-  StrAccum *pAccum,                  /* Accumulate results here */
-  int useExtended,                   /* Allow extended %-conversions */
-  const char *fmt,                   /* Format string */
-  va_list ap                         /* arguments */
-){
-  int c;                     /* Next character in the format string */
-  char *bufpt;               /* Pointer to the conversion buffer */
-  int precision;             /* Precision of the current field */
-  int length;                /* Length of the field */
-  int idx;                   /* A general purpose loop counter */
-  int width;                 /* Width of the current field */
-  etByte flag_leftjustify;   /* True if "-" flag is present */
-  etByte flag_plussign;      /* True if "+" flag is present */
-  etByte flag_blanksign;     /* True if " " flag is present */
-  etByte flag_alternateform; /* True if "#" flag is present */
-  etByte flag_altform2;      /* True if "!" flag is present */
-  etByte flag_zeropad;       /* True if field width constant starts with zero */
-  etByte flag_long;          /* True if "l" flag is present */
-  etByte flag_longlong;      /* True if the "ll" flag is present */
-  etByte done;               /* Loop termination flag */
-  etByte xtype = 0;          /* Conversion paradigm */
-  char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
-  sqlite_uint64 longvalue;   /* Value for integer types */
-  LONGDOUBLE_TYPE realvalue; /* Value for real types */
-  const et_info *infop;      /* Pointer to the appropriate info structure */
-  char *zOut;                /* Rendering buffer */
-  int nOut;                  /* Size of the rendering buffer */
-  char *zExtra;              /* Malloced memory used by some conversion */
-#ifndef SQLITE_OMIT_FLOATING_POINT
-  int  exp, e2;              /* exponent of real numbers */
-  int nsd;                   /* Number of significant digits returned */
-  double rounder;            /* Used for rounding floating point values */
-  etByte flag_dp;            /* True if decimal point should be shown */
-  etByte flag_rtz;           /* True if trailing zeros should be removed */
-#endif
-  char buf[etBUFSIZE];       /* Conversion buffer */
-
-  bufpt = 0;
-  for(; (c=(*fmt))!=0; ++fmt){
-    if( c!='%' ){
-      int amt;
-      bufpt = (char *)fmt;
-      amt = 1;
-      while( (c=(*++fmt))!='%' && c!=0 ) amt++;
-      sqlite3StrAccumAppend(pAccum, bufpt, amt);
-      if( c==0 ) break;
-    }
-    if( (c=(*++fmt))==0 ){
-      sqlite3StrAccumAppend(pAccum, "%", 1);
-      break;
-    }
-    /* Find out what flags are present */
-    flag_leftjustify = flag_plussign = flag_blanksign = 
-     flag_alternateform = flag_altform2 = flag_zeropad = 0;
-    done = 0;
-    do{
-      switch( c ){
-        case '-':   flag_leftjustify = 1;     break;
-        case '+':   flag_plussign = 1;        break;
-        case ' ':   flag_blanksign = 1;       break;
-        case '#':   flag_alternateform = 1;   break;
-        case '!':   flag_altform2 = 1;        break;
-        case '0':   flag_zeropad = 1;         break;
-        default:    done = 1;                 break;
-      }
-    }while( !done && (c=(*++fmt))!=0 );
-    /* Get the field width */
-    width = 0;
-    if( c=='*' ){
-      width = va_arg(ap,int);
-      if( width<0 ){
-        flag_leftjustify = 1;
-        width = -width;
-      }
-      c = *++fmt;
-    }else{
-      while( c>='0' && c<='9' ){
-        width = width*10 + c - '0';
-        c = *++fmt;
-      }
-    }
-    /* Get the precision */
-    if( c=='.' ){
-      precision = 0;
-      c = *++fmt;
-      if( c=='*' ){
-        precision = va_arg(ap,int);
-        if( precision<0 ) precision = -precision;
-        c = *++fmt;
-      }else{
-        while( c>='0' && c<='9' ){
-          precision = precision*10 + c - '0';
-          c = *++fmt;
-        }
-      }
-    }else{
-      precision = -1;
-    }
-    /* Get the conversion type modifier */
-    if( c=='l' ){
-      flag_long = 1;
-      c = *++fmt;
-      if( c=='l' ){
-        flag_longlong = 1;
-        c = *++fmt;
-      }else{
-        flag_longlong = 0;
-      }
-    }else{
-      flag_long = flag_longlong = 0;
-    }
-    /* Fetch the info entry for the field */
-    infop = &fmtinfo[0];
-    xtype = etINVALID;
-    for(idx=0; idx<ArraySize(fmtinfo); idx++){
-      if( c==fmtinfo[idx].fmttype ){
-        infop = &fmtinfo[idx];
-        if( useExtended || (infop->flags & FLAG_INTERN)==0 ){
-          xtype = infop->type;
-        }else{
-          return;
-        }
-        break;
-      }
-    }
-    zExtra = 0;
-
-    /*
-    ** At this point, variables are initialized as follows:
-    **
-    **   flag_alternateform          TRUE if a '#' is present.
-    **   flag_altform2               TRUE if a '!' is present.
-    **   flag_plussign               TRUE if a '+' is present.
-    **   flag_leftjustify            TRUE if a '-' is present or if the
-    **                               field width was negative.
-    **   flag_zeropad                TRUE if the width began with 0.
-    **   flag_long                   TRUE if the letter 'l' (ell) prefixed
-    **                               the conversion character.
-    **   flag_longlong               TRUE if the letter 'll' (ell ell) prefixed
-    **                               the conversion character.
-    **   flag_blanksign              TRUE if a ' ' is present.
-    **   width                       The specified field width.  This is
-    **                               always non-negative.  Zero is the default.
-    **   precision                   The specified precision.  The default
-    **                               is -1.
-    **   xtype                       The class of the conversion.
-    **   infop                       Pointer to the appropriate info struct.
-    */
-    switch( xtype ){
-      case etPOINTER:
-        flag_longlong = sizeof(char*)==sizeof(i64);
-        flag_long = sizeof(char*)==sizeof(long int);
-        /* Fall through into the next case */
-      case etORDINAL:
-      case etRADIX:
-        if( infop->flags & FLAG_SIGNED ){
-          i64 v;
-          if( flag_longlong ){
-            v = va_arg(ap,i64);
-          }else if( flag_long ){
-            v = va_arg(ap,long int);
-          }else{
-            v = va_arg(ap,int);
-          }
-          if( v<0 ){
-            if( v==SMALLEST_INT64 ){
-              longvalue = ((u64)1)<<63;
-            }else{
-              longvalue = -v;
-            }
-            prefix = '-';
-          }else{
-            longvalue = v;
-            if( flag_plussign )        prefix = '+';
-            else if( flag_blanksign )  prefix = ' ';
-            else                       prefix = 0;
-          }
-        }else{
-          if( flag_longlong ){
-            longvalue = va_arg(ap,u64);
-          }else if( flag_long ){
-            longvalue = va_arg(ap,unsigned long int);
-          }else{
-            longvalue = va_arg(ap,unsigned int);
-          }
-          prefix = 0;
-        }
-        if( longvalue==0 ) flag_alternateform = 0;
-        if( flag_zeropad && precision<width-(prefix!=0) ){
-          precision = width-(prefix!=0);
-        }
-        if( precision<etBUFSIZE-10 ){
-          nOut = etBUFSIZE;
-          zOut = buf;
-        }else{
-          nOut = precision + 10;
-          zOut = zExtra = sqlite3Malloc( nOut );
-          if( zOut==0 ){
-            pAccum->accError = STRACCUM_NOMEM;
-            return;
-          }
-        }
-        bufpt = &zOut[nOut-1];
-        if( xtype==etORDINAL ){
-          static const char zOrd[] = "thstndrd";
-          int x = (int)(longvalue % 10);
-          if( x>=4 || (longvalue/10)%10==1 ){
-            x = 0;
-          }
-          *(--bufpt) = zOrd[x*2+1];
-          *(--bufpt) = zOrd[x*2];
-        }
-        {
-          register const char *cset;      /* Use registers for speed */
-          register int base;
-          cset = &aDigits[infop->charset];
-          base = infop->base;
-          do{                                           /* Convert to ascii */
-            *(--bufpt) = cset[longvalue%base];
-            longvalue = longvalue/base;
-          }while( longvalue>0 );
-        }
-        length = (int)(&zOut[nOut-1]-bufpt);
-        for(idx=precision-length; idx>0; idx--){
-          *(--bufpt) = '0';                             /* Zero pad */
-        }
-        if( prefix ) *(--bufpt) = prefix;               /* Add sign */
-        if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
-          const char *pre;
-          char x;
-          pre = &aPrefix[infop->prefix];
-          for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
-        }
-        length = (int)(&zOut[nOut-1]-bufpt);
-        break;
-      case etFLOAT:
-      case etEXP:
-      case etGENERIC:
-        realvalue = va_arg(ap,double);
-#ifdef SQLITE_OMIT_FLOATING_POINT
-        length = 0;
-#else
-        if( precision<0 ) precision = 6;         /* Set default precision */
-        if( realvalue<0.0 ){
-          realvalue = -realvalue;
-          prefix = '-';
-        }else{
-          if( flag_plussign )          prefix = '+';
-          else if( flag_blanksign )    prefix = ' ';
-          else                         prefix = 0;
-        }
-        if( xtype==etGENERIC && precision>0 ) precision--;
-        for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
-        if( xtype==etFLOAT ) realvalue += rounder;
-        /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
-        exp = 0;
-        if( sqlite3IsNaN((double)realvalue) ){
-          bufpt = "NaN";
-          length = 3;
-          break;
-        }
-        if( realvalue>0.0 ){
-          LONGDOUBLE_TYPE scale = 1.0;
-          while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
-          while( realvalue>=1e64*scale && exp<=350 ){ scale *= 1e64; exp+=64; }
-          while( realvalue>=1e8*scale && exp<=350 ){ scale *= 1e8; exp+=8; }
-          while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
-          realvalue /= scale;
-          while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
-          while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
-          if( exp>350 ){
-            if( prefix=='-' ){
-              bufpt = "-Inf";
-            }else if( prefix=='+' ){
-              bufpt = "+Inf";
-            }else{
-              bufpt = "Inf";
-            }
-            length = sqlite3Strlen30(bufpt);
-            break;
-          }
-        }
-        bufpt = buf;
-        /*
-        ** If the field type is etGENERIC, then convert to either etEXP
-        ** or etFLOAT, as appropriate.
-        */
-        if( xtype!=etFLOAT ){
-          realvalue += rounder;
-          if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
-        }
-        if( xtype==etGENERIC ){
-          flag_rtz = !flag_alternateform;
-          if( exp<-4 || exp>precision ){
-            xtype = etEXP;
-          }else{
-            precision = precision - exp;
-            xtype = etFLOAT;
-          }
-        }else{
-          flag_rtz = flag_altform2;
-        }
-        if( xtype==etEXP ){
-          e2 = 0;
-        }else{
-          e2 = exp;
-        }
-        if( MAX(e2,0)+precision+width > etBUFSIZE - 15 ){
-          bufpt = zExtra = sqlite3Malloc( MAX(e2,0)+precision+width+15 );
-          if( bufpt==0 ){
-            pAccum->accError = STRACCUM_NOMEM;
-            return;
-          }
-        }
-        zOut = bufpt;
-        nsd = 16 + flag_altform2*10;
-        flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
-        /* The sign in front of the number */
-        if( prefix ){
-          *(bufpt++) = prefix;
-        }
-        /* Digits prior to the decimal point */
-        if( e2<0 ){
-          *(bufpt++) = '0';
-        }else{
-          for(; e2>=0; e2--){
-            *(bufpt++) = et_getdigit(&realvalue,&nsd);
-          }
-        }
-        /* The decimal point */
-        if( flag_dp ){
-          *(bufpt++) = '.';
-        }
-        /* "0" digits after the decimal point but before the first
-        ** significant digit of the number */
-        for(e2++; e2<0; precision--, e2++){
-          assert( precision>0 );
-          *(bufpt++) = '0';
-        }
-        /* Significant digits after the decimal point */
-        while( (precision--)>0 ){
-          *(bufpt++) = et_getdigit(&realvalue,&nsd);
-        }
-        /* Remove trailing zeros and the "." if no digits follow the "." */
-        if( flag_rtz && flag_dp ){
-          while( bufpt[-1]=='0' ) *(--bufpt) = 0;
-          assert( bufpt>zOut );
-          if( bufpt[-1]=='.' ){
-            if( flag_altform2 ){
-              *(bufpt++) = '0';
-            }else{
-              *(--bufpt) = 0;
-            }
-          }
-        }
-        /* Add the "eNNN" suffix */
-        if( xtype==etEXP ){
-          *(bufpt++) = aDigits[infop->charset];
-          if( exp<0 ){
-            *(bufpt++) = '-'; exp = -exp;
-          }else{
-            *(bufpt++) = '+';
-          }
-          if( exp>=100 ){
-            *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
-            exp %= 100;
-          }
-          *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
-          *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
-        }
-        *bufpt = 0;
-
-        /* The converted number is in buf[] and zero terminated. Output it.
-        ** Note that the number is in the usual order, not reversed as with
-        ** integer conversions. */
-        length = (int)(bufpt-zOut);
-        bufpt = zOut;
-
-        /* Special case:  Add leading zeros if the flag_zeropad flag is
-        ** set and we are not left justified */
-        if( flag_zeropad && !flag_leftjustify && length < width){
-          int i;
-          int nPad = width - length;
-          for(i=width; i>=nPad; i--){
-            bufpt[i] = bufpt[i-nPad];
-          }
-          i = prefix!=0;
-          while( nPad-- ) bufpt[i++] = '0';
-          length = width;
-        }
-#endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
-        break;
-      case etSIZE:
-        *(va_arg(ap,int*)) = pAccum->nChar;
-        length = width = 0;
-        break;
-      case etPERCENT:
-        buf[0] = '%';
-        bufpt = buf;
-        length = 1;
-        break;
-      case etCHARX:
-        c = va_arg(ap,int);
-        buf[0] = (char)c;
-        if( precision>=0 ){
-          for(idx=1; idx<precision; idx++) buf[idx] = (char)c;
-          length = precision;
-        }else{
-          length =1;
-        }
-        bufpt = buf;
-        break;
-      case etSTRING:
-      case etDYNSTRING:
-        bufpt = va_arg(ap,char*);
-        if( bufpt==0 ){
-          bufpt = "";
-        }else if( xtype==etDYNSTRING ){
-          zExtra = bufpt;
-        }
-        if( precision>=0 ){
-          for(length=0; length<precision && bufpt[length]; length++){}
-        }else{
-          length = sqlite3Strlen30(bufpt);
-        }
-        break;
-      case etSQLESCAPE:
-      case etSQLESCAPE2:
-      case etSQLESCAPE3: {
-        int i, j, k, n, isnull;
-        int needQuote;
-        char ch;
-        char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
-        char *escarg = va_arg(ap,char*);
-        isnull = escarg==0;
-        if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
-        k = precision;
-        for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
-          if( ch==q )  n++;
-        }
-        needQuote = !isnull && xtype==etSQLESCAPE2;
-        n += i + 1 + needQuote*2;
-        if( n>etBUFSIZE ){
-          bufpt = zExtra = sqlite3Malloc( n );
-          if( bufpt==0 ){
-            pAccum->accError = STRACCUM_NOMEM;
-            return;
-          }
-        }else{
-          bufpt = buf;
-        }
-        j = 0;
-        if( needQuote ) bufpt[j++] = q;
-        k = i;
-        for(i=0; i<k; i++){
-          bufpt[j++] = ch = escarg[i];
-          if( ch==q ) bufpt[j++] = ch;
-        }
-        if( needQuote ) bufpt[j++] = q;
-        bufpt[j] = 0;
-        length = j;
-        /* The precision in %q and %Q means how many input characters to
-        ** consume, not the length of the output...
-        ** if( precision>=0 && precision<length ) length = precision; */
-        break;
-      }
-      case etTOKEN: {
-        Token *pToken = va_arg(ap, Token*);
-        if( pToken ){
-          sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
-        }
-        length = width = 0;
-        break;
-      }
-      case etSRCLIST: {
-        SrcList *pSrc = va_arg(ap, SrcList*);
-        int k = va_arg(ap, int);
-        struct SrcList_item *pItem = &pSrc->a[k];
-        assert( k>=0 && k<pSrc->nSrc );
-        if( pItem->zDatabase ){
-          sqlite3StrAccumAppend(pAccum, pItem->zDatabase, -1);
-          sqlite3StrAccumAppend(pAccum, ".", 1);
-        }
-        sqlite3StrAccumAppend(pAccum, pItem->zName, -1);
-        length = width = 0;
-        break;
-      }
-      default: {
-        assert( xtype==etINVALID );
-        return;
-      }
-    }/* End switch over the format type */
-    /*
-    ** The text of the conversion is pointed to by "bufpt" and is
-    ** "length" characters long.  The field width is "width".  Do
-    ** the output.
-    */
-    if( !flag_leftjustify ){
-      register int nspace;
-      nspace = width-length;
-      if( nspace>0 ){
-        sqlite3AppendSpace(pAccum, nspace);
-      }
-    }
-    if( length>0 ){
-      sqlite3StrAccumAppend(pAccum, bufpt, length);
-    }
-    if( flag_leftjustify ){
-      register int nspace;
-      nspace = width-length;
-      if( nspace>0 ){
-        sqlite3AppendSpace(pAccum, nspace);
-      }
-    }
-    sqlite3_free(zExtra);
-  }/* End for loop over the format string */
-} /* End of function */
-
-/*
-** Append N bytes of text from z to the StrAccum object.
-*/
-SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
-  assert( z!=0 || N==0 );
-  if( p->accError ){
-    testcase(p->accError==STRACCUM_TOOBIG);
-    testcase(p->accError==STRACCUM_NOMEM);
-    return;
-  }
-  assert( p->zText!=0 || p->nChar==0 );
-  if( N<=0 ){
-    if( N==0 || z[0]==0 ) return;
-    N = sqlite3Strlen30(z);
-  }
-  if( p->nChar+N >= p->nAlloc ){
-    char *zNew;
-    if( !p->useMalloc ){
-      p->accError = STRACCUM_TOOBIG;
-      N = p->nAlloc - p->nChar - 1;
-      if( N<=0 ){
-        return;
-      }
-    }else{
-      char *zOld = (p->zText==p->zBase ? 0 : p->zText);
-      i64 szNew = p->nChar;
-      szNew += N + 1;
-      if( szNew > p->mxAlloc ){
-        sqlite3StrAccumReset(p);
-        p->accError = STRACCUM_TOOBIG;
-        return;
-      }else{
-        p->nAlloc = (int)szNew;
-      }
-      if( p->useMalloc==1 ){
-        zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
-      }else{
-        zNew = sqlite3_realloc(zOld, p->nAlloc);
-      }
-      if( zNew ){
-        if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
-        p->zText = zNew;
-      }else{
-        p->accError = STRACCUM_NOMEM;
-        sqlite3StrAccumReset(p);
-        return;
-      }
-    }
-  }
-  assert( p->zText );
-  memcpy(&p->zText[p->nChar], z, N);
-  p->nChar += N;
-}
-
-/*
-** Finish off a string by making sure it is zero-terminated.
-** Return a pointer to the resulting string.  Return a NULL
-** pointer if any kind of error was encountered.
-*/
-SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
-  if( p->zText ){
-    p->zText[p->nChar] = 0;
-    if( p->useMalloc && p->zText==p->zBase ){
-      if( p->useMalloc==1 ){
-        p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
-      }else{
-        p->zText = sqlite3_malloc(p->nChar+1);
-      }
-      if( p->zText ){
-        memcpy(p->zText, p->zBase, p->nChar+1);
-      }else{
-        p->accError = STRACCUM_NOMEM;
-      }
-    }
-  }
-  return p->zText;
-}
-
-/*
-** Reset an StrAccum string.  Reclaim all malloced memory.
-*/
-SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
-  if( p->zText!=p->zBase ){
-    if( p->useMalloc==1 ){
-      sqlite3DbFree(p->db, p->zText);
-    }else{
-      sqlite3_free(p->zText);
-    }
-  }
-  p->zText = 0;
-}
-
-/*
-** Initialize a string accumulator
-*/
-SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
-  p->zText = p->zBase = zBase;
-  p->db = 0;
-  p->nChar = 0;
-  p->nAlloc = n;
-  p->mxAlloc = mx;
-  p->useMalloc = 1;
-  p->accError = 0;
-}
-
-/*
-** Print into memory obtained from sqliteMalloc().  Use the internal
-** %-conversion extensions.
-*/
-SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
-  char *z;
-  char zBase[SQLITE_PRINT_BUF_SIZE];
-  StrAccum acc;
-  assert( db!=0 );
-  sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
-                      db->aLimit[SQLITE_LIMIT_LENGTH]);
-  acc.db = db;
-  sqlite3VXPrintf(&acc, 1, zFormat, ap);
-  z = sqlite3StrAccumFinish(&acc);
-  if( acc.accError==STRACCUM_NOMEM ){
-    db->mallocFailed = 1;
-  }
-  return z;
-}
-
-/*
-** Print into memory obtained from sqliteMalloc().  Use the internal
-** %-conversion extensions.
-*/
-SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
-  va_list ap;
-  char *z;
-  va_start(ap, zFormat);
-  z = sqlite3VMPrintf(db, zFormat, ap);
-  va_end(ap);
-  return z;
-}
-
-/*
-** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
-** the string and before returnning.  This routine is intended to be used
-** to modify an existing string.  For example:
-**
-**       x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
-**
-*/
-SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
-  va_list ap;
-  char *z;
-  va_start(ap, zFormat);
-  z = sqlite3VMPrintf(db, zFormat, ap);
-  va_end(ap);
-  sqlite3DbFree(db, zStr);
-  return z;
-}
-
-/*
-** Print into memory obtained from sqlite3_malloc().  Omit the internal
-** %-conversion extensions.
-*/
-SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
-  char *z;
-  char zBase[SQLITE_PRINT_BUF_SIZE];
-  StrAccum acc;
-#ifndef SQLITE_OMIT_AUTOINIT
-  if( sqlite3_initialize() ) return 0;
-#endif
-  sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
-  acc.useMalloc = 2;
-  sqlite3VXPrintf(&acc, 0, zFormat, ap);
-  z = sqlite3StrAccumFinish(&acc);
-  return z;
-}
-
-/*
-** Print into memory obtained from sqlite3_malloc()().  Omit the internal
-** %-conversion extensions.
-*/
-SQLITE_API char *sqlite3_mprintf(const char *zFormat, ...){
-  va_list ap;
-  char *z;
-#ifndef SQLITE_OMIT_AUTOINIT
-  if( sqlite3_initialize() ) return 0;
-#endif
-  va_start(ap, zFormat);
-  z = sqlite3_vmprintf(zFormat, ap);
-  va_end(ap);
-  return z;
-}
-
-/*
-** sqlite3_snprintf() works like snprintf() except that it ignores the
-** current locale settings.  This is important for SQLite because we
-** are not able to use a "," as the decimal point in place of "." as
-** specified by some locales.
-**
-** Oops:  The first two arguments of sqlite3_snprintf() are backwards
-** from the snprintf() standard.  Unfortunately, it is too late to change
-** this without breaking compatibility, so we just have to live with the
-** mistake.
-**
-** sqlite3_vsnprintf() is the varargs version.
-*/
-SQLITE_API char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
-  StrAccum acc;
-  if( n<=0 ) return zBuf;
-  sqlite3StrAccumInit(&acc, zBuf, n, 0);
-  acc.useMalloc = 0;
-  sqlite3VXPrintf(&acc, 0, zFormat, ap);
-  return sqlite3StrAccumFinish(&acc);
-}
-SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
-  char *z;
-  va_list ap;
-  va_start(ap,zFormat);
-  z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
-  va_end(ap);
-  return z;
-}
-
-/*
-** This is the routine that actually formats the sqlite3_log() message.
-** We house it in a separate routine from sqlite3_log() to avoid using
-** stack space on small-stack systems when logging is disabled.
-**
-** sqlite3_log() must render into a static buffer.  It cannot dynamically
-** allocate memory because it might be called while the memory allocator
-** mutex is held.
-*/
-static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
-  StrAccum acc;                          /* String accumulator */
-  char zMsg[SQLITE_PRINT_BUF_SIZE*3];    /* Complete log message */
-
-  sqlite3StrAccumInit(&acc, zMsg, sizeof(zMsg), 0);
-  acc.useMalloc = 0;
-  sqlite3VXPrintf(&acc, 0, zFormat, ap);
-  sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
-                           sqlite3StrAccumFinish(&acc));
-}
-
-/*
-** Format and write a message to the log if logging is enabled.
-*/
-SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...){
-  va_list ap;                             /* Vararg list */
-  if( sqlite3GlobalConfig.xLog ){
-    va_start(ap, zFormat);
-    renderLogMsg(iErrCode, zFormat, ap);
-    va_end(ap);
-  }
-}
-
-#if defined(SQLITE_DEBUG)
-/*
-** A version of printf() that understands %lld.  Used for debugging.
-** The printf() built into some versions of windows does not understand %lld
-** and segfaults if you give it a long long int.
-*/
-SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
-  va_list ap;
-  StrAccum acc;
-  char zBuf[500];
-  sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
-  acc.useMalloc = 0;
-  va_start(ap,zFormat);
-  sqlite3VXPrintf(&acc, 0, zFormat, ap);
-  va_end(ap);
-  sqlite3StrAccumFinish(&acc);
-  fprintf(stdout,"%s", zBuf);
-  fflush(stdout);
-}
-#endif
-
-#ifndef SQLITE_OMIT_TRACE
-/*
-** variable-argument wrapper around sqlite3VXPrintf().
-*/
-SQLITE_PRIVATE void sqlite3XPrintf(StrAccum *p, const char *zFormat, ...){
-  va_list ap;
-  va_start(ap,zFormat);
-  sqlite3VXPrintf(p, 1, zFormat, ap);
-  va_end(ap);
-}
-#endif
-
-/************** End of printf.c **********************************************/
-/************** Begin file random.c ******************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains code to implement a pseudo-random number
-** generator (PRNG) for SQLite.
-**
-** Random numbers are used by some of the database backends in order
-** to generate random integer keys for tables or random filenames.
-*/
-
-
-/* All threads share a single random number generator.
-** This structure is the current state of the generator.
-*/
-static SQLITE_WSD struct sqlite3PrngType {
-  unsigned char isInit;          /* True if initialized */
-  unsigned char i, j;            /* State variables */
-  unsigned char s[256];          /* State variables */
-} sqlite3Prng;
-
-/*
-** Return N random bytes.
-*/
-SQLITE_API void sqlite3_randomness(int N, void *pBuf){
-  unsigned char t;
-  unsigned char *zBuf = pBuf;
-
-  /* The "wsdPrng" macro will resolve to the pseudo-random number generator
-  ** state vector.  If writable static data is unsupported on the target,
-  ** we have to locate the state vector at run-time.  In the more common
-  ** case where writable static data is supported, wsdPrng can refer directly
-  ** to the "sqlite3Prng" state vector declared above.
-  */
-#ifdef SQLITE_OMIT_WSD
-  struct sqlite3PrngType *p = &GLOBAL(struct sqlite3PrngType, sqlite3Prng);
-# define wsdPrng p[0]
-#else
-# define wsdPrng sqlite3Prng
-#endif
-
-#if SQLITE_THREADSAFE
-  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
-  sqlite3_mutex_enter(mutex);
-#endif
-
-  /* Initialize the state of the random number generator once,
-  ** the first time this routine is called.  The seed value does
-  ** not need to contain a lot of randomness since we are not
-  ** trying to do secure encryption or anything like that...
-  **
-  ** Nothing in this file or anywhere else in SQLite does any kind of
-  ** encryption.  The RC4 algorithm is being used as a PRNG (pseudo-random
-  ** number generator) not as an encryption device.
-  */
-  if( !wsdPrng.isInit ){
-    int i;
-    char k[256];
-    wsdPrng.j = 0;
-    wsdPrng.i = 0;
-    sqlite3OsRandomness(sqlite3_vfs_find(0), 256, k);
-    for(i=0; i<256; i++){
-      wsdPrng.s[i] = (u8)i;
-    }
-    for(i=0; i<256; i++){
-      wsdPrng.j += wsdPrng.s[i] + k[i];
-      t = wsdPrng.s[wsdPrng.j];
-      wsdPrng.s[wsdPrng.j] = wsdPrng.s[i];
-      wsdPrng.s[i] = t;
-    }
-    wsdPrng.isInit = 1;
-  }
-
-  while( N-- ){
-    wsdPrng.i++;
-    t = wsdPrng.s[wsdPrng.i];
-    wsdPrng.j += t;
-    wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
-    wsdPrng.s[wsdPrng.j] = t;
-    t += wsdPrng.s[wsdPrng.i];
-    *(zBuf++) = wsdPrng.s[t];
-  }
-  sqlite3_mutex_leave(mutex);
-}
-
-#ifndef SQLITE_OMIT_BUILTIN_TEST
-/*
-** For testing purposes, we sometimes want to preserve the state of
-** PRNG and restore the PRNG to its saved state at a later time, or
-** to reset the PRNG to its initial state.  These routines accomplish
-** those tasks.
-**
-** The sqlite3_test_control() interface calls these routines to
-** control the PRNG.
-*/
-static SQLITE_WSD struct sqlite3PrngType sqlite3SavedPrng;
-SQLITE_PRIVATE void sqlite3PrngSaveState(void){
-  memcpy(
-    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
-    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
-    sizeof(sqlite3Prng)
-  );
-}
-SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
-  memcpy(
-    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
-    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
-    sizeof(sqlite3Prng)
-  );
-}
-SQLITE_PRIVATE void sqlite3PrngResetState(void){
-  GLOBAL(struct sqlite3PrngType, sqlite3Prng).isInit = 0;
-}
-#endif /* SQLITE_OMIT_BUILTIN_TEST */
-
-/************** End of random.c **********************************************/
-/************** Begin file utf.c *********************************************/
-/*
-** 2004 April 13
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains routines used to translate between UTF-8, 
-** UTF-16, UTF-16BE, and UTF-16LE.
-**
-** Notes on UTF-8:
-**
-**   Byte-0    Byte-1    Byte-2    Byte-3    Value
-**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
-**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
-**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
-**  11110uuu  10uuzzzz  10yyyyyy  10xxxxxx   000uuuuu zzzzyyyy yyxxxxxx
-**
-**
-** Notes on UTF-16:  (with wwww+1==uuuuu)
-**
-**      Word-0               Word-1          Value
-**  110110ww wwzzzzyy   110111yy yyxxxxxx    000uuuuu zzzzyyyy yyxxxxxx
-**  zzzzyyyy yyxxxxxx                        00000000 zzzzyyyy yyxxxxxx
-**
-**
-** BOM or Byte Order Mark:
-**     0xff 0xfe   little-endian utf-16 follows
-**     0xfe 0xff   big-endian utf-16 follows
-**
-*/
-/* #include <assert.h> */
-
-#ifndef SQLITE_AMALGAMATION
-/*
-** The following constant value is used by the SQLITE_BIGENDIAN and
-** SQLITE_LITTLEENDIAN macros.
-*/
-SQLITE_PRIVATE const int sqlite3one = 1;
-#endif /* SQLITE_AMALGAMATION */
-
-/*
-** This lookup table is used to help decode the first byte of
-** a multi-byte UTF8 character.
-*/
-static const unsigned char sqlite3Utf8Trans1[] = {
-  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
-  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
-  0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
-  0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
-  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
-  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
-  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
-  0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
-};
-
-
-#define WRITE_UTF8(zOut, c) {                          \
-  if( c<0x00080 ){                                     \
-    *zOut++ = (u8)(c&0xFF);                            \
-  }                                                    \
-  else if( c<0x00800 ){                                \
-    *zOut++ = 0xC0 + (u8)((c>>6)&0x1F);                \
-    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
-  }                                                    \
-  else if( c<0x10000 ){                                \
-    *zOut++ = 0xE0 + (u8)((c>>12)&0x0F);               \
-    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
-    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
-  }else{                                               \
-    *zOut++ = 0xF0 + (u8)((c>>18) & 0x07);             \
-    *zOut++ = 0x80 + (u8)((c>>12) & 0x3F);             \
-    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
-    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
-  }                                                    \
-}
-
-#define WRITE_UTF16LE(zOut, c) {                                    \
-  if( c<=0xFFFF ){                                                  \
-    *zOut++ = (u8)(c&0x00FF);                                       \
-    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
-  }else{                                                            \
-    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
-    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
-    *zOut++ = (u8)(c&0x00FF);                                       \
-    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
-  }                                                                 \
-}
-
-#define WRITE_UTF16BE(zOut, c) {                                    \
-  if( c<=0xFFFF ){                                                  \
-    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
-    *zOut++ = (u8)(c&0x00FF);                                       \
-  }else{                                                            \
-    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
-    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
-    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
-    *zOut++ = (u8)(c&0x00FF);                                       \
-  }                                                                 \
-}
-
-#define READ_UTF16LE(zIn, TERM, c){                                   \
-  c = (*zIn++);                                                       \
-  c += ((*zIn++)<<8);                                                 \
-  if( c>=0xD800 && c<0xE000 && TERM ){                                \
-    int c2 = (*zIn++);                                                \
-    c2 += ((*zIn++)<<8);                                              \
-    c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
-  }                                                                   \
-}
-
-#define READ_UTF16BE(zIn, TERM, c){                                   \
-  c = ((*zIn++)<<8);                                                  \
-  c += (*zIn++);                                                      \
-  if( c>=0xD800 && c<0xE000 && TERM ){                                \
-    int c2 = ((*zIn++)<<8);                                           \
-    c2 += (*zIn++);                                                   \
-    c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
-  }                                                                   \
-}
-
-/*
-** Translate a single UTF-8 character.  Return the unicode value.
-**
-** During translation, assume that the byte that zTerm points
-** is a 0x00.
-**
-** Write a pointer to the next unread byte back into *pzNext.
-**
-** Notes On Invalid UTF-8:
-**
-**  *  This routine never allows a 7-bit character (0x00 through 0x7f) to
-**     be encoded as a multi-byte character.  Any multi-byte character that
-**     attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
-**
-**  *  This routine never allows a UTF16 surrogate value to be encoded.
-**     If a multi-byte character attempts to encode a value between
-**     0xd800 and 0xe000 then it is rendered as 0xfffd.
-**
-**  *  Bytes in the range of 0x80 through 0xbf which occur as the first
-**     byte of a character are interpreted as single-byte characters
-**     and rendered as themselves even though they are technically
-**     invalid characters.
-**
-**  *  This routine accepts an infinite number of different UTF8 encodings
-**     for unicode values 0x80 and greater.  It do not change over-length
-**     encodings to 0xfffd as some systems recommend.
-*/
-#define READ_UTF8(zIn, zTerm, c)                           \
-  c = *(zIn++);                                            \
-  if( c>=0xc0 ){                                           \
-    c = sqlite3Utf8Trans1[c-0xc0];                         \
-    while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){            \
-      c = (c<<6) + (0x3f & *(zIn++));                      \
-    }                                                      \
-    if( c<0x80                                             \
-        || (c&0xFFFFF800)==0xD800                          \
-        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }        \
-  }
-SQLITE_PRIVATE u32 sqlite3Utf8Read(
-  const unsigned char **pz    /* Pointer to string from which to read char */
-){
-  unsigned int c;
-
-  /* Same as READ_UTF8() above but without the zTerm parameter.
-  ** For this routine, we assume the UTF8 string is always zero-terminated.
-  */
-  c = *((*pz)++);
-  if( c>=0xc0 ){
-    c = sqlite3Utf8Trans1[c-0xc0];
-    while( (*(*pz) & 0xc0)==0x80 ){
-      c = (c<<6) + (0x3f & *((*pz)++));
-    }
-    if( c<0x80
-        || (c&0xFFFFF800)==0xD800
-        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }
-  }
-  return c;
-}
-
-
-
-
-/*
-** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
-** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
-*/ 
-/* #define TRANSLATE_TRACE 1 */
-
-#ifndef SQLITE_OMIT_UTF16
-/*
-** This routine transforms the internal text encoding used by pMem to
-** desiredEnc. It is an error if the string is already of the desired
-** encoding, or if *pMem does not contain a string value.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
-  int len;                    /* Maximum length of output string in bytes */
-  unsigned char *zOut;                  /* Output buffer */
-  unsigned char *zIn;                   /* Input iterator */
-  unsigned char *zTerm;                 /* End of input */
-  unsigned char *z;                     /* Output iterator */
-  unsigned int c;
-
-  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
-  assert( pMem->flags&MEM_Str );
-  assert( pMem->enc!=desiredEnc );
-  assert( pMem->enc!=0 );
-  assert( pMem->n>=0 );
-
-#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
-  {
-    char zBuf[100];
-    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
-    fprintf(stderr, "INPUT:  %s\n", zBuf);
-  }
-#endif
-
-  /* If the translation is between UTF-16 little and big endian, then 
-  ** all that is required is to swap the byte order. This case is handled
-  ** differently from the others.
-  */
-  if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){
-    u8 temp;
-    int rc;
-    rc = sqlite3VdbeMemMakeWriteable(pMem);
-    if( rc!=SQLITE_OK ){
-      assert( rc==SQLITE_NOMEM );
-      return SQLITE_NOMEM;
-    }
-    zIn = (u8*)pMem->z;
-    zTerm = &zIn[pMem->n&~1];
-    while( zIn<zTerm ){
-      temp = *zIn;
-      *zIn = *(zIn+1);
-      zIn++;
-      *zIn++ = temp;
-    }
-    pMem->enc = desiredEnc;
-    goto translate_out;
-  }
-
-  /* Set len to the maximum number of bytes required in the output buffer. */
-  if( desiredEnc==SQLITE_UTF8 ){
-    /* When converting from UTF-16, the maximum growth results from
-    ** translating a 2-byte character to a 4-byte UTF-8 character.
-    ** A single byte is required for the output string
-    ** nul-terminator.
-    */
-    pMem->n &= ~1;
-    len = pMem->n * 2 + 1;
-  }else{
-    /* When converting from UTF-8 to UTF-16 the maximum growth is caused
-    ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
-    ** character. Two bytes are required in the output buffer for the
-    ** nul-terminator.
-    */
-    len = pMem->n * 2 + 2;
-  }
-
-  /* Set zIn to point at the start of the input buffer and zTerm to point 1
-  ** byte past the end.
-  **
-  ** Variable zOut is set to point at the output buffer, space obtained
-  ** from sqlite3_malloc().
-  */
-  zIn = (u8*)pMem->z;
-  zTerm = &zIn[pMem->n];
-  zOut = sqlite3DbMallocRaw(pMem->db, len);
-  if( !zOut ){
-    return SQLITE_NOMEM;
-  }
-  z = zOut;
-
-  if( pMem->enc==SQLITE_UTF8 ){
-    if( desiredEnc==SQLITE_UTF16LE ){
-      /* UTF-8 -> UTF-16 Little-endian */
-      while( zIn<zTerm ){
-        READ_UTF8(zIn, zTerm, c);
-        WRITE_UTF16LE(z, c);
-      }
-    }else{
-      assert( desiredEnc==SQLITE_UTF16BE );
-      /* UTF-8 -> UTF-16 Big-endian */
-      while( zIn<zTerm ){
-        READ_UTF8(zIn, zTerm, c);
-        WRITE_UTF16BE(z, c);
-      }
-    }
-    pMem->n = (int)(z - zOut);
-    *z++ = 0;
-  }else{
-    assert( desiredEnc==SQLITE_UTF8 );
-    if( pMem->enc==SQLITE_UTF16LE ){
-      /* UTF-16 Little-endian -> UTF-8 */
-      while( zIn<zTerm ){
-        READ_UTF16LE(zIn, zIn<zTerm, c); 
-        WRITE_UTF8(z, c);
-      }
-    }else{
-      /* UTF-16 Big-endian -> UTF-8 */
-      while( zIn<zTerm ){
-        READ_UTF16BE(zIn, zIn<zTerm, c); 
-        WRITE_UTF8(z, c);
-      }
-    }
-    pMem->n = (int)(z - zOut);
-  }
-  *z = 0;
-  assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
-
-  sqlite3VdbeMemRelease(pMem);
-  pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem);
-  pMem->enc = desiredEnc;
-  pMem->flags |= (MEM_Term|MEM_Dyn);
-  pMem->z = (char*)zOut;
-  pMem->zMalloc = pMem->z;
-
-translate_out:
-#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
-  {
-    char zBuf[100];
-    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
-    fprintf(stderr, "OUTPUT: %s\n", zBuf);
-  }
-#endif
-  return SQLITE_OK;
-}
-
-/*
-** This routine checks for a byte-order mark at the beginning of the 
-** UTF-16 string stored in *pMem. If one is present, it is removed and
-** the encoding of the Mem adjusted. This routine does not do any
-** byte-swapping, it just sets Mem.enc appropriately.
-**
-** The allocation (static, dynamic etc.) and encoding of the Mem may be
-** changed by this function.
-*/
-SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem){
-  int rc = SQLITE_OK;
-  u8 bom = 0;
-
-  assert( pMem->n>=0 );
-  if( pMem->n>1 ){
-    u8 b1 = *(u8 *)pMem->z;
-    u8 b2 = *(((u8 *)pMem->z) + 1);
-    if( b1==0xFE && b2==0xFF ){
-      bom = SQLITE_UTF16BE;
-    }
-    if( b1==0xFF && b2==0xFE ){
-      bom = SQLITE_UTF16LE;
-    }
-  }
-  
-  if( bom ){
-    rc = sqlite3VdbeMemMakeWriteable(pMem);
-    if( rc==SQLITE_OK ){
-      pMem->n -= 2;
-      memmove(pMem->z, &pMem->z[2], pMem->n);
-      pMem->z[pMem->n] = '\0';
-      pMem->z[pMem->n+1] = '\0';
-      pMem->flags |= MEM_Term;
-      pMem->enc = bom;
-    }
-  }
-  return rc;
-}
-#endif /* SQLITE_OMIT_UTF16 */
-
-/*
-** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
-** return the number of unicode characters in pZ up to (but not including)
-** the first 0x00 byte. If nByte is not less than zero, return the
-** number of unicode characters in the first nByte of pZ (or up to 
-** the first 0x00, whichever comes first).
-*/
-SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *zIn, int nByte){
-  int r = 0;
-  const u8 *z = (const u8*)zIn;
-  const u8 *zTerm;
-  if( nByte>=0 ){
-    zTerm = &z[nByte];
-  }else{
-    zTerm = (const u8*)(-1);
-  }
-  assert( z<=zTerm );
-  while( *z!=0 && z<zTerm ){
-    SQLITE_SKIP_UTF8(z);
-    r++;
-  }
-  return r;
-}
-
-/* This test function is not currently used by the automated test-suite. 
-** Hence it is only available in debug builds.
-*/
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-/*
-** Translate UTF-8 to UTF-8.
-**
-** This has the effect of making sure that the string is well-formed
-** UTF-8.  Miscoded characters are removed.
-**
-** The translation is done in-place and aborted if the output
-** overruns the input.
-*/
-SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char *zIn){
-  unsigned char *zOut = zIn;
-  unsigned char *zStart = zIn;
-  u32 c;
-
-  while( zIn[0] && zOut<=zIn ){
-    c = sqlite3Utf8Read((const u8**)&zIn);
-    if( c!=0xfffd ){
-      WRITE_UTF8(zOut, c);
-    }
-  }
-  *zOut = 0;
-  return (int)(zOut - zStart);
-}
-#endif
-
-#ifndef SQLITE_OMIT_UTF16
-/*
-** Convert a UTF-16 string in the native encoding into a UTF-8 string.
-** Memory to hold the UTF-8 string is obtained from sqlite3_malloc and must
-** be freed by the calling function.
-**
-** NULL is returned if there is an allocation error.
-*/
-SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte, u8 enc){
-  Mem m;
-  memset(&m, 0, sizeof(m));
-  m.db = db;
-  sqlite3VdbeMemSetStr(&m, z, nByte, enc, SQLITE_STATIC);
-  sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8);
-  if( db->mallocFailed ){
-    sqlite3VdbeMemRelease(&m);
-    m.z = 0;
-  }
-  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
-  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
-  assert( (m.flags & MEM_Dyn)!=0 || db->mallocFailed );
-  assert( m.z || db->mallocFailed );
-  return m.z;
-}
-
-/*
-** zIn is a UTF-16 encoded unicode string at least nChar characters long.
-** Return the number of bytes in the first nChar unicode characters
-** in pZ.  nChar must be non-negative.
-*/
-SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
-  int c;
-  unsigned char const *z = zIn;
-  int n = 0;
-  
-  if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
-    while( n<nChar ){
-      READ_UTF16BE(z, 1, c);
-      n++;
-    }
-  }else{
-    while( n<nChar ){
-      READ_UTF16LE(z, 1, c);
-      n++;
-    }
-  }
-  return (int)(z-(unsigned char const *)zIn);
-}
-
-#if defined(SQLITE_TEST)
-/*
-** This routine is called from the TCL test function "translate_selftest".
-** It checks that the primitives for serializing and deserializing
-** characters in each encoding are inverses of each other.
-*/
-SQLITE_PRIVATE void sqlite3UtfSelfTest(void){
-  unsigned int i, t;
-  unsigned char zBuf[20];
-  unsigned char *z;
-  int n;
-  unsigned int c;
-
-  for(i=0; i<0x00110000; i++){
-    z = zBuf;
-    WRITE_UTF8(z, i);
-    n = (int)(z-zBuf);
-    assert( n>0 && n<=4 );
-    z[0] = 0;
-    z = zBuf;
-    c = sqlite3Utf8Read((const u8**)&z);
-    t = i;
-    if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
-    if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
-    assert( c==t );
-    assert( (z-zBuf)==n );
-  }
-  for(i=0; i<0x00110000; i++){
-    if( i>=0xD800 && i<0xE000 ) continue;
-    z = zBuf;
-    WRITE_UTF16LE(z, i);
-    n = (int)(z-zBuf);
-    assert( n>0 && n<=4 );
-    z[0] = 0;
-    z = zBuf;
-    READ_UTF16LE(z, 1, c);
-    assert( c==i );
-    assert( (z-zBuf)==n );
-  }
-  for(i=0; i<0x00110000; i++){
-    if( i>=0xD800 && i<0xE000 ) continue;
-    z = zBuf;
-    WRITE_UTF16BE(z, i);
-    n = (int)(z-zBuf);
-    assert( n>0 && n<=4 );
-    z[0] = 0;
-    z = zBuf;
-    READ_UTF16BE(z, 1, c);
-    assert( c==i );
-    assert( (z-zBuf)==n );
-  }
-}
-#endif /* SQLITE_TEST */
-#endif /* SQLITE_OMIT_UTF16 */
-
-/************** End of utf.c *************************************************/
-/************** Begin file util.c ********************************************/
-/*
-** 2001 September 15
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** Utility functions used throughout sqlite.
-**
-** This file contains functions for allocating memory, comparing
-** strings, and stuff like that.
-**
-*/
-/* #include <stdarg.h> */
-#ifdef SQLITE_HAVE_ISNAN
-# include <math.h>
-#endif
-
-/*
-** Routine needed to support the testcase() macro.
-*/
-#ifdef SQLITE_COVERAGE_TEST
-SQLITE_PRIVATE void sqlite3Coverage(int x){
-  static unsigned dummy = 0;
-  dummy += (unsigned)x;
-}
-#endif
-
-#ifndef SQLITE_OMIT_FLOATING_POINT
-/*
-** Return true if the floating point value is Not a Number (NaN).
-**
-** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
-** Otherwise, we have our own implementation that works on most systems.
-*/
-SQLITE_PRIVATE int sqlite3IsNaN(double x){
-  int rc;   /* The value return */
-#if !defined(SQLITE_HAVE_ISNAN)
-  /*
-  ** Systems that support the isnan() library function should probably
-  ** make use of it by compiling with -DSQLITE_HAVE_ISNAN.  But we have
-  ** found that many systems do not have a working isnan() function so
-  ** this implementation is provided as an alternative.
-  **
-  ** This NaN test sometimes fails if compiled on GCC with -ffast-math.
-  ** On the other hand, the use of -ffast-math comes with the following
-  ** warning:
-  **
-  **      This option [-ffast-math] should never be turned on by any
-  **      -O option since it can result in incorrect output for programs
-  **      which depend on an exact implementation of IEEE or ISO 
-  **      rules/specifications for math functions.
-  **
-  ** Under MSVC, this NaN test may fail if compiled with a floating-
-  ** point precision mode other than /fp:precise.  From the MSDN 
-  ** documentation:
-  **
-  **      The compiler [with /fp:precise] will properly handle comparisons 
-  **      involving NaN. For example, x != x evaluates to true if x is NaN 
-  **      ...
-  */
-#ifdef __FAST_MATH__
-# error SQLite will not work correctly with the -ffast-math option of GCC.
-#endif
-  volatile double y = x;
-  volatile double z = y;
-  rc = (y!=z);
-#else  /* if defined(SQLITE_HAVE_ISNAN) */
-  rc = isnan(x);
-#endif /* SQLITE_HAVE_ISNAN */
-  testcase( rc );
-  return rc;
-}
-#endif /* SQLITE_OMIT_FLOATING_POINT */
-
-/*
-** Compute a string length that is limited to what can be stored in
-** lower 30 bits of a 32-bit signed integer.
-**
-** The value returned will never be negative.  Nor will it ever be greater
-** than the actual length of the string.  For very long strings (greater
-** than 1GiB) the value returned might be less than the true string length.
-*/
-SQLITE_PRIVATE int sqlite3Strlen30(const char *z){
-  const char *z2 = z;
-  if( z==0 ) return 0;
-  while( *z2 ){ z2++; }
-  return 0x3fffffff & (int)(z2 - z);
-}
-
-/*
-** Set the most recent error code and error string for the sqlite
-** handle "db". The error code is set to "err_code".
-**
-** If it is not NULL, string zFormat specifies the format of the
-** error string in the style of the printf functions: The following
-** format characters are allowed:
-**
-**      %s      Insert a string
-**      %z      A string that should be freed after use
-**      %d      Insert an integer
-**      %T      Insert a token
-**      %S      Insert the first element of a SrcList
-**
-** zFormat and any string tokens that follow it are assumed to be
-** encoded in UTF-8.
-**
-** To clear the most recent error for sqlite handle "db", sqlite3Error
-** should be called with err_code set to SQLITE_OK and zFormat set
-** to NULL.
-*/
-SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat, ...){
-  if( db && (db->pErr || (db->pErr = sqlite3ValueNew(db))!=0) ){
-    db->errCode = err_code;
-    if( zFormat ){
-      char *z;
-      va_list ap;
-      va_start(ap, zFormat);
-      z = sqlite3VMPrintf(db, zFormat, ap);
-      va_end(ap);
-      sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
-    }else{
-      sqlite3ValueSetStr(db->pErr, 0, 0, SQLITE_UTF8, SQLITE_STATIC);
-    }
-  }
-}
-
-/*
-** Add an error message to pParse->zErrMsg and increment pParse->nErr.
-** The following formatting characters are allowed:
-**
-**      %s      Insert a string
-**      %z      A string that should be freed after use
-**      %d      Insert an integer
-**      %T      Insert a token
-**      %S      Insert the first element of a SrcList
-**
-** This function should be used to report any error that occurs whilst
-** compiling an SQL statement (i.e. within sqlite3_prepare()). The
-** last thing the sqlite3_prepare() function does is copy the error
-** stored by this function into the database handle using sqlite3Error().
-** Function sqlite3Error() should be used during statement execution
-** (sqlite3_step() etc.).
-*/
-SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
-  char *zMsg;
-  va_list ap;
-  sqlite3 *db = pParse->db;
-  va_start(ap, zFormat);
-  zMsg = sqlite3VMPrintf(db, zFormat, ap);
-  va_end(ap);
-  if( db->suppressErr ){
-    sqlite3DbFree(db, zMsg);
-  }else{
-    pParse->nErr++;
-    sqlite3DbFree(db, pParse->zErrMsg);
-    pParse->zErrMsg = zMsg;
-    pParse->rc = SQLITE_ERROR;
-  }
-}
-
-/*
-** Convert an SQL-style quoted string into a normal string by removing
-** the quote characters.  The conversion is done in-place.  If the
-** input does not begin with a quote character, then this routine
-** is a no-op.
-**
-** The input string must be zero-terminated.  A new zero-terminator
-** is added to the dequoted string.
-**
-** The return value is -1 if no dequoting occurs or the length of the
-** dequoted string, exclusive of the zero terminator, if dequoting does
-** occur.
-**
-** 2002-Feb-14: This routine is extended to remove MS-Access style
-** brackets from around identifers.  For example:  "[a-b-c]" becomes
-** "a-b-c".
-*/
-SQLITE_PRIVATE int sqlite3Dequote(char *z){
-  char quote;
-  int i, j;
-  if( z==0 ) return -1;
-  quote = z[0];
-  switch( quote ){
-    case '\'':  break;
-    case '"':   break;
-    case '`':   break;                /* For MySQL compatibility */
-    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
-    default:    return -1;
-  }
-  for(i=1, j=0;; i++){
-    assert( z[i] );
-    if( z[i]==quote ){
-      if( z[i+1]==quote ){
-        z[j++] = quote;
-        i++;
-      }else{
-        break;
-      }
-    }else{
-      z[j++] = z[i];
-    }
-  }
-  z[j] = 0;
-  return j;
-}
-
-/* Convenient short-hand */
-#define UpperToLower sqlite3UpperToLower
-
-/*
-** Some systems have stricmp().  Others have strcasecmp().  Because
-** there is no consistency, we will define our own.
-**
-** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
-** sqlite3_strnicmp() APIs allow applications and extensions to compare
-** the contents of two buffers containing UTF-8 strings in a
-** case-independent fashion, using the same definition of "case
-** independence" that SQLite uses internally when comparing identifiers.
-*/
-SQLITE_API int sqlite3_stricmp(const char *zLeft, const char *zRight){
-  register unsigned char *a, *b;
-  a = (unsigned char *)zLeft;
-  b = (unsigned char *)zRight;
-  while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
-  return UpperToLower[*a] - UpperToLower[*b];
-}
-SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
-  register unsigned char *a, *b;
-  a = (unsigned char *)zLeft;
-  b = (unsigned char *)zRight;
-  while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
-  return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
-}
-
-/*
-** The string z[] is an text representation of a real number.
-** Convert this string to a double and write it into *pResult.
-**
-** The string z[] is length bytes in length (bytes, not characters) and
-** uses the encoding enc.  The string is not necessarily zero-terminated.
-**
-** Return TRUE if the result is a valid real number (or integer) and FALSE
-** if the string is empty or contains extraneous text.  Valid numbers
-** are in one of these formats:
-**
-**    [+-]digits[E[+-]digits]
-**    [+-]digits.[digits][E[+-]digits]
-**    [+-].digits[E[+-]digits]
-**
-** Leading and trailing whitespace is ignored for the purpose of determining
-** validity.
-**
-** If some prefix of the input string is a valid number, this routine
-** returns FALSE but it still converts the prefix and writes the result
-** into *pResult.
-*/
-SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
-#ifndef SQLITE_OMIT_FLOATING_POINT
-  int incr;
-  const char *zEnd = z + length;
-  /* sign * significand * (10 ^ (esign * exponent)) */
-  int sign = 1;    /* sign of significand */
-  i64 s = 0;       /* significand */
-  int d = 0;       /* adjust exponent for shifting decimal point */
-  int esign = 1;   /* sign of exponent */
-  int e = 0;       /* exponent */
-  int eValid = 1;  /* True exponent is either not used or is well-formed */
-  double result;
-  int nDigits = 0;
-  int nonNum = 0;
-
-  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
-  *pResult = 0.0;   /* Default return value, in case of an error */
-
-  if( enc==SQLITE_UTF8 ){
-    incr = 1;
-  }else{
-    int i;
-    incr = 2;
-    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
-    for(i=3-enc; i<length && z[i]==0; i+=2){}
-    nonNum = i<length;
-    zEnd = z+i+enc-3;
-    z += (enc&1);
-  }
-
-  /* skip leading spaces */
-  while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
-  if( z>=zEnd ) return 0;
-
-  /* get sign of significand */
-  if( *z=='-' ){
-    sign = -1;
-    z+=incr;
-  }else if( *z=='+' ){
-    z+=incr;
-  }
-
-  /* skip leading zeroes */
-  while( z<zEnd && z[0]=='0' ) z+=incr, nDigits++;
-
-  /* copy max significant digits to significand */
-  while( z<zEnd && sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
-    s = s*10 + (*z - '0');
-    z+=incr, nDigits++;
-  }
-
-  /* skip non-significant significand digits
-  ** (increase exponent by d to shift decimal left) */
-  while( z<zEnd && sqlite3Isdigit(*z) ) z+=incr, nDigits++, d++;
-  if( z>=zEnd ) goto do_atof_calc;
-
-  /* if decimal point is present */
-  if( *z=='.' ){
-    z+=incr;
-    /* copy digits from after decimal to significand
-    ** (decrease exponent by d to shift decimal right) */
-    while( z<zEnd && sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
-      s = s*10 + (*z - '0');
-      z+=incr, nDigits++, d--;
-    }
-    /* skip non-significant digits */
-    while( z<zEnd && sqlite3Isdigit(*z) ) z+=incr, nDigits++;
-  }
-  if( z>=zEnd ) goto do_atof_calc;
-
-  /* if exponent is present */
-  if( *z=='e' || *z=='E' ){
-    z+=incr;
-    eValid = 0;
-    if( z>=zEnd ) goto do_atof_calc;
-    /* get sign of exponent */
-    if( *z=='-' ){
-      esign = -1;
-      z+=incr;
-    }else if( *z=='+' ){
-      z+=incr;
-    }
-    /* copy digits to exponent */
-    while( z<zEnd && sqlite3Isdigit(*z) ){
-      e = e<10000 ? (e*10 + (*z - '0')) : 10000;
-      z+=incr;
-      eValid = 1;
-    }
-  }
-
-  /* skip trailing spaces */
-  if( nDigits && eValid ){
-    while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
-  }
-
-do_atof_calc:
-  /* adjust exponent by d, and update sign */
-  e = (e*esign) + d;
-  if( e<0 ) {
-    esign = -1;
-    e *= -1;
-  } else {
-    esign = 1;
-  }
-
-  /* if 0 significand */
-  if( !s ) {
-    /* In the IEEE 754 standard, zero is signed.
-    ** Add the sign if we've seen at least one digit */
-    result = (sign<0 && nDigits) ? -(double)0 : (double)0;
-  } else {
-    /* attempt to reduce exponent */
-    if( esign>0 ){
-      while( s<(LARGEST_INT64/10) && e>0 ) e--,s*=10;
-    }else{
-      while( !(s%10) && e>0 ) e--,s/=10;
-    }
-
-    /* adjust the sign of significand */
-    s = sign<0 ? -s : s;
-
-    /* if exponent, scale significand as appropriate
-    ** and store in result. */
-    if( e ){
-      LONGDOUBLE_TYPE scale = 1.0;
-      /* attempt to handle extremely small/large numbers better */
-      if( e>307 && e<342 ){
-        while( e%308 ) { scale *= 1.0e+1; e -= 1; }
-        if( esign<0 ){
-          result = s / scale;
-          result /= 1.0e+308;
-        }else{
-          result = s * scale;
-          result *= 1.0e+308;
-        }
-      }else if( e>=342 ){
-        if( esign<0 ){
-          result = 0.0*s;
-        }else{
-          result = 1e308*1e308*s;  /* Infinity */
-        }
-      }else{
-        /* 1.0e+22 is the largest power of 10 than can be 
-        ** represented exactly. */
-        while( e%22 ) { scale *= 1.0e+1; e -= 1; }
-        while( e>0 ) { scale *= 1.0e+22; e -= 22; }
-        if( esign<0 ){
-          result = s / scale;
-        }else{
-          result = s * scale;
-        }
-      }
-    } else {
-      result = (double)s;
-    }
-  }
-
-  /* store the result */
-  *pResult = result;
-
-  /* return true if number and no extra non-whitespace chracters after */
-  return z>=zEnd && nDigits>0 && eValid && nonNum==0;
-#else
-  return !sqlite3Atoi64(z, pResult, length, enc);
-#endif /* SQLITE_OMIT_FLOATING_POINT */
-}
-
-/*
-** Compare the 19-character string zNum against the text representation
-** value 2^63:  9223372036854775808.  Return negative, zero, or positive
-** if zNum is less than, equal to, or greater than the string.
-** Note that zNum must contain exactly 19 characters.
-**
-** Unlike memcmp() this routine is guaranteed to return the difference
-** in the values of the last digit if the only difference is in the
-** last digit.  So, for example,
-**
-**      compare2pow63("9223372036854775800", 1)
-**
-** will return -8.
-*/
-static int compare2pow63(const char *zNum, int incr){
-  int c = 0;
-  int i;
-                    /* 012345678901234567 */
-  const char *pow63 = "922337203685477580";
-  for(i=0; c==0 && i<18; i++){
-    c = (zNum[i*incr]-pow63[i])*10;
-  }
-  if( c==0 ){
-    c = zNum[18*incr] - '8';
-    testcase( c==(-1) );
-    testcase( c==0 );
-    testcase( c==(+1) );
-  }
-  return c;
-}
-
-
-/*
-** Convert zNum to a 64-bit signed integer.
-**
-** If the zNum value is representable as a 64-bit twos-complement 
-** integer, then write that value into *pNum and return 0.
-**
-** If zNum is exactly 9223372036854665808, return 2.  This special
-** case is broken out because while 9223372036854665808 cannot be a 
-** signed 64-bit integer, its negative -9223372036854665808 can be.
-**
-** If zNum is too big for a 64-bit integer and is not
-** 9223372036854665808  or if zNum contains any non-numeric text,
-** then return 1.
-**
-** length is the number of bytes in the string (bytes, not characters).
-** The string is not necessarily zero-terminated.  The encoding is
-** given by enc.
-*/
-SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
-  int incr;
-  u64 u = 0;
-  int neg = 0; /* assume positive */
-  int i;
-  int c = 0;
-  int nonNum = 0;
-  const char *zStart;
-  const char *zEnd = zNum + length;
-  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
-  if( enc==SQLITE_UTF8 ){
-    incr = 1;
-  }else{
-    incr = 2;
-    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
-    for(i=3-enc; i<length && zNum[i]==0; i+=2){}
-    nonNum = i<length;
-    zEnd = zNum+i+enc-3;
-    zNum += (enc&1);
-  }
-  while( zNum<zEnd && sqlite3Isspace(*zNum) ) zNum+=incr;
-  if( zNum<zEnd ){
-    if( *zNum=='-' ){
-      neg = 1;
-      zNum+=incr;
-    }else if( *zNum=='+' ){
-      zNum+=incr;
-    }
-  }
-  zStart = zNum;
-  while( zNum<zEnd && zNum[0]=='0' ){ zNum+=incr; } /* Skip leading zeros. */
-  for(i=0; &zNum[i]<zEnd && (c=zNum[i])>='0' && c<='9'; i+=incr){
-    u = u*10 + c - '0';
-  }
-  if( u>LARGEST_INT64 ){
-    *pNum = SMALLEST_INT64;
-  }else if( neg ){
-    *pNum = -(i64)u;
-  }else{
-    *pNum = (i64)u;
-  }
-  testcase( i==18 );
-  testcase( i==19 );
-  testcase( i==20 );
-  if( (c!=0 && &zNum[i]<zEnd) || (i==0 && zStart==zNum) || i>19*incr || nonNum ){
-    /* zNum is empty or contains non-numeric text or is longer
-    ** than 19 digits (thus guaranteeing that it is too large) */
-    return 1;
-  }else if( i<19*incr ){
-    /* Less than 19 digits, so we know that it fits in 64 bits */
-    assert( u<=LARGEST_INT64 );
-    return 0;
-  }else{
-    /* zNum is a 19-digit numbers.  Compare it against 9223372036854775808. */
-    c = compare2pow63(zNum, incr);
-    if( c<0 ){
-      /* zNum is less than 9223372036854775808 so it fits */
-      assert( u<=LARGEST_INT64 );
-      return 0;
-    }else if( c>0 ){
-      /* zNum is greater than 9223372036854775808 so it overflows */
-      return 1;
-    }else{
-      /* zNum is exactly 9223372036854775808.  Fits if negative.  The
-      ** special case 2 overflow if positive */
-      assert( u-1==LARGEST_INT64 );
-      assert( (*pNum)==SMALLEST_INT64 );
-      return neg ? 0 : 2;
-    }
-  }
-}
-
-/*
-** If zNum represents an integer that will fit in 32-bits, then set
-** *pValue to that integer and return true.  Otherwise return false.
-**
-** Any non-numeric characters that following zNum are ignored.
-** This is different from sqlite3Atoi64() which requires the
-** input number to be zero-terminated.
-*/
-SQLITE_PRIVATE int sqlite3GetInt32(const char *zNum, int *pValue){
-  sqlite_int64 v = 0;
-  int i, c;
-  int neg = 0;
-  if( zNum[0]=='-' ){
-    neg = 1;
-    zNum++;
-  }else if( zNum[0]=='+' ){
-    zNum++;
-  }
-  while( zNum[0]=='0' ) zNum++;
-  for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){
-    v = v*10 + c;
-  }
-
-  /* The longest decimal representation of a 32 bit integer is 10 digits:
-  **
-  **             1234567890
-  **     2^31 -> 2147483648
-  */
-  testcase( i==10 );
-  if( i>10 ){
-    return 0;
-  }
-  testcase( v-neg==2147483647 );
-  if( v-neg>2147483647 ){
-    return 0;
-  }
-  if( neg ){
-    v = -v;
-  }
-  *pValue = (int)v;
-  return 1;
-}
-
-/*
-** Return a 32-bit integer value extracted from a string.  If the
-** string is not an integer, just return 0.
-*/
-SQLITE_PRIVATE int sqlite3Atoi(const char *z){
-  int x = 0;
-  if( z ) sqlite3GetInt32(z, &x);
-  return x;
-}
-
-/*
-** The variable-length integer encoding is as follows:
-**
-** KEY:
-**         A = 0xxxxxxx    7 bits of data and one flag bit
-**         B = 1xxxxxxx    7 bits of data and one flag bit
-**         C = xxxxxxxx    8 bits of data
-**
-**  7 bits - A
-** 14 bits - BA
-** 21 bits - BBA
-** 28 bits - BBBA
-** 35 bits - BBBBA
-** 42 bits - BBBBBA
-** 49 bits - BBBBBBA
-** 56 bits - BBBBBBBA
-** 64 bits - BBBBBBBBC
-*/
-
-/*
-** Write a 64-bit variable-length integer to memory starting at p[0].
-** The length of data write will be between 1 and 9 bytes.  The number
-** of bytes written is returned.
-**
-** A variable-length integer consists of the lower 7 bits of each byte
-** for all bytes that have the 8th bit set and one byte with the 8th
-** bit clear.  Except, if we get to the 9th byte, it stores the full
-** 8 bits and is the last byte.
-*/
-SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
-  int i, j, n;
-  u8 buf[10];
-  if( v & (((u64)0xff000000)<<32) ){
-    p[8] = (u8)v;
-    v >>= 8;
-    for(i=7; i>=0; i--){
-      p[i] = (u8)((v & 0x7f) | 0x80);
-      v >>= 7;
-    }
-    return 9;
-  }    
-  n = 0;
-  do{
-    buf[n++] = (u8)((v & 0x7f) | 0x80);
-    v >>= 7;
-  }while( v!=0 );
-  buf[0] &= 0x7f;
-  assert( n<=9 );
-  for(i=0, j=n-1; j>=0; j--, i++){
-    p[i] = buf[j];
-  }
-  return n;
-}
-
-/*
-** This routine is a faster version of sqlite3PutVarint() that only
-** works for 32-bit positive integers and which is optimized for
-** the common case of small integers.  A MACRO version, putVarint32,
-** is provided which inlines the single-byte case.  All code should use
-** the MACRO version as this function assumes the single-byte case has
-** already been handled.
-*/
-SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char *p, u32 v){
-#ifndef putVarint32
-  if( (v & ~0x7f)==0 ){
-    p[0] = v;
-    return 1;
-  }
-#endif
-  if( (v & ~0x3fff)==0 ){
-    p[0] = (u8)((v>>7) | 0x80);
-    p[1] = (u8)(v & 0x7f);
-    return 2;
-  }
-  return sqlite3PutVarint(p, v);
-}
-
-/*
-** Bitmasks used by sqlite3GetVarint().  These precomputed constants
-** are defined here rather than simply putting the constant expressions
-** inline in order to work around bugs in the RVT compiler.
-**
-** SLOT_2_0     A mask for  (0x7f<<14) | 0x7f
-**
-** SLOT_4_2_0   A mask for  (0x7f<<28) | SLOT_2_0
-*/
-#define SLOT_2_0     0x001fc07f
-#define SLOT_4_2_0   0xf01fc07f
-
-
-/*
-** Read a 64-bit variable-length integer from memory starting at p[0].
-** Return the number of bytes read.  The value is stored in *v.
-*/
-SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
-  u32 a,b,s;
-
-  a = *p;
-  /* a: p0 (unmasked) */
-  if (!(a&0x80))
-  {
-    *v = a;
-    return 1;
-  }
-
-  p++;
-  b = *p;
-  /* b: p1 (unmasked) */
-  if (!(b&0x80))
-  {
-    a &= 0x7f;
-    a = a<<7;
-    a |= b;
-    *v = a;
-    return 2;
-  }
-
-  /* Verify that constants are precomputed correctly */
-  assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) );
-  assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) );
-
-  p++;
-  a = a<<14;
-  a |= *p;
-  /* a: p0<<14 | p2 (unmasked) */
-  if (!(a&0x80))
-  {
-    a &= SLOT_2_0;
-    b &= 0x7f;
-    b = b<<7;
-    a |= b;
-    *v = a;
-    return 3;
-  }
-
-  /* CSE1 from below */
-  a &= SLOT_2_0;
-  p++;
-  b = b<<14;
-  b |= *p;
-  /* b: p1<<14 | p3 (unmasked) */
-  if (!(b&0x80))
-  {
-    b &= SLOT_2_0;
-    /* moved CSE1 up */
-    /* a &= (0x7f<<14)|(0x7f); */
-    a = a<<7;
-    a |= b;
-    *v = a;
-    return 4;
-  }
-
-  /* a: p0<<14 | p2 (masked) */
-  /* b: p1<<14 | p3 (unmasked) */
-  /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
-  /* moved CSE1 up */
-  /* a &= (0x7f<<14)|(0x7f); */
-  b &= SLOT_2_0;
-  s = a;
-  /* s: p0<<14 | p2 (masked) */
-
-  p++;
-  a = a<<14;
-  a |= *p;
-  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
-  if (!(a&0x80))
-  {
-    /* we can skip these cause they were (effectively) done above in calc'ing s */
-    /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
-    /* b &= (0x7f<<14)|(0x7f); */
-    b = b<<7;
-    a |= b;
-    s = s>>18;
-    *v = ((u64)s)<<32 | a;
-    return 5;
-  }
-
-  /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
-  s = s<<7;
-  s |= b;
-  /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
-
-  p++;
-  b = b<<14;
-  b |= *p;
-  /* b: p1<<28 | p3<<14 | p5 (unmasked) */
-  if (!(b&0x80))
-  {
-    /* we can skip this cause it was (effectively) done above in calc'ing s */
-    /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
-    a &= SLOT_2_0;
-    a = a<<7;
-    a |= b;
-    s = s>>18;
-    *v = ((u64)s)<<32 | a;
-    return 6;
-  }
-
-  p++;
-  a = a<<14;
-  a |= *p;
-  /* a: p2<<28 | p4<<14 | p6 (unmasked) */
-  if (!(a&0x80))
-  {
-    a &= SLOT_4_2_0;
-    b &= SLOT_2_0;
-    b = b<<7;
-    a |= b;
-    s = s>>11;
-    *v = ((u64)s)<<32 | a;
-    return 7;
-  }
-
-  /* CSE2 from below */
-  a &= SLOT_2_0;
-  p++;
-  b = b<<14;
-  b |= *p;
-  /* b: p3<<28 | p5<<14 | p7 (unmasked) */
-  if (!(b&0x80))
-  {
-    b &= SLOT_4_2_0;
-    /* moved CSE2 up */
-    /* a &= (0x7f<<14)|(0x7f); */
-    a = a<<7;
-    a |= b;
-    s = s>>4;
-    *v = ((u64)s)<<32 | a;
-    return 8;
-  }
-
-  p++;
-  a = a<<15;
-  a |= *p;
-  /* a: p4<<29 | p6<<15 | p8 (unmasked) */
-
-  /* moved CSE2 up */
-  /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
-  b &= SLOT_2_0;
-  b = b<<8;
-  a |= b;
-
-  s = s<<4;
-  b = p[-4];
-  b &= 0x7f;
-  b = b>>3;
-  s |= b;
-
-  *v = ((u64)s)<<32 | a;
-
-  return 9;
-}
-
-/*
-** Read a 32-bit variable-length integer from memory starting at p[0].
-** Return the number of bytes read.  The value is stored in *v.
-**
-** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
-** integer, then set *v to 0xffffffff.
-**
-** A MACRO version, getVarint32, is provided which inlines the 
-** single-byte case.  All code should use the MACRO version as 
-** this function assumes the single-byte case has already been handled.
-*/
-SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
-  u32 a,b;
-
-  /* The 1-byte case.  Overwhelmingly the most common.  Handled inline
-  ** by the getVarin32() macro */
-  a = *p;
-  /* a: p0 (unmasked) */
-#ifndef getVarint32
-  if (!(a&0x80))
-  {
-    /* Values between 0 and 127 */
-    *v = a;
-    return 1;
-  }
-#endif
-
-  /* The 2-byte case */
-  p++;
-  b = *p;
-  /* b: p1 (unmasked) */
-  if (!(b&0x80))
-  {
-    /* Values between 128 and 16383 */
-    a &= 0x7f;
-    a = a<<7;
-    *v = a | b;
-    return 2;
-  }
-
-  /* The 3-byte case */
-  p++;
-  a = a<<14;
-  a |= *p;
-  /* a: p0<<14 | p2 (unmasked) */
-  if (!(a&0x80))
-  {
-    /* Values between 16384 and 2097151 */
-    a &= (0x7f<<14)|(0x7f);
-    b &= 0x7f;
-    b = b<<7;
-    *v = a | b;
-    return 3;
-  }
-
-  /* A 32-bit varint is used to store size information in btrees.
-  ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
-  ** A 3-byte varint is sufficient, for example, to record the size
-  ** of a 1048569-byte BLOB or string.
-  **
-  ** We only unroll the first 1-, 2-, and 3- byte cases.  The very
-  ** rare larger cases can be handled by the slower 64-bit varint
-  ** routine.
-  */
-#if 1
-  {
-    u64 v64;
-    u8 n;
-
-    p -= 2;
-    n = sqlite3GetVarint(p, &v64);
-    assert( n>3 && n<=9 );
-    if( (v64 & SQLITE_MAX_U32)!=v64 ){
-      *v = 0xffffffff;
-    }else{
-      *v = (u32)v64;
-    }
-    return n;
-  }
-
-#else
-  /* For following code (kept for historical record only) shows an
-  ** unrolling for the 3- and 4-byte varint cases.  This code is
-  ** slightly faster, but it is also larger and much harder to test.
-  */
-  p++;
-  b = b<<14;
-  b |= *p;
-  /* b: p1<<14 | p3 (unmasked) */
-  if (!(b&0x80))
-  {
-    /* Values between 2097152 and 268435455 */
-    b &= (0x7f<<14)|(0x7f);
-    a &= (0x7f<<14)|(0x7f);
-    a = a<<7;
-    *v = a | b;
-    return 4;
-  }
-
-  p++;
-  a = a<<14;
-  a |= *p;
-  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
-  if (!(a&0x80))
-  {
-    /* Values  between 268435456 and 34359738367 */
-    a &= SLOT_4_2_0;
-    b &= SLOT_4_2_0;
-    b = b<<7;
-    *v = a | b;
-    return 5;
-  }
-
-  /* We can only reach this point when reading a corrupt database
-  ** file.  In that case we are not in any hurry.  Use the (relatively
-  ** slow) general-purpose sqlite3GetVarint() routine to extract the
-  ** value. */
-  {
-    u64 v64;
-    u8 n;
-
-    p -= 4;
-    n = sqlite3GetVarint(p, &v64);
-    assert( n>5 && n<=9 );
-    *v = (u32)v64;
-    return n;
-  }
-#endif
-}
-
-/*
-** Return the number of bytes that will be needed to store the given
-** 64-bit integer.
-*/
-SQLITE_PRIVATE int sqlite3VarintLen(u64 v){
-  int i = 0;
-  do{
-    i++;
-    v >>= 7;
-  }while( v!=0 && ALWAYS(i<9) );
-  return i;
-}
-
-
-/*
-** Read or write a four-byte big-endian integer value.
-*/
-SQLITE_PRIVATE u32 sqlite3Get4byte(const u8 *p){
-  return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
-}
-SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
-  p[0] = (u8)(v>>24);
-  p[1] = (u8)(v>>16);
-  p[2] = (u8)(v>>8);
-  p[3] = (u8)v;
-}
-
-
-
-/*
-** Translate a single byte of Hex into an integer.
-** This routine only works if h really is a valid hexadecimal
-** character:  0..9a..fA..F
-*/
-SQLITE_PRIVATE u8 sqlite3HexToInt(int h){
-  assert( (h>='0' && h<='9') ||  (h>='a' && h<='f') ||  (h>='A' && h<='F') );
-#ifdef SQLITE_ASCII
-  h += 9*(1&(h>>6));
-#endif
-#ifdef SQLITE_EBCDIC
-  h += 9*(1&~(h>>4));
-#endif
-  return (u8)(h & 0xf);
-}
-
-#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
-/*
-** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
-** value.  Return a pointer to its binary value.  Space to hold the
-** binary value has been obtained from malloc and must be freed by
-** the calling routine.
-*/
-SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){
-  char *zBlob;
-  int i;
-
-  zBlob = (char *)sqlite3DbMallocRaw(db, n/2 + 1);
-  n--;
-  if( zBlob ){
-    for(i=0; i<n; i+=2){
-      zBlob[i/2] = (sqlite3HexToInt(z[i])<<4) | sqlite3HexToInt(z[i+1]);
-    }
-    zBlob[i/2] = 0;
-  }
-  return zBlob;
-}
-#endif /* !SQLITE_OMIT_BLOB_LITERAL || SQLITE_HAS_CODEC */
-
-/*
-** Log an error that is an API call on a connection pointer that should
-** not have been used.  The "type" of connection pointer is given as the
-** argument.  The zType is a word like "NULL" or "closed" or "invalid".
-*/
-static void logBadConnection(const char *zType){
-  sqlite3_log(SQLITE_MISUSE, 
-     "API call with %s database connection pointer",
-     zType
-  );
-}
-
-/*
-** Check to make sure we have a valid db pointer.  This test is not
-** foolproof but it does provide some measure of protection against
-** misuse of the interface such as passing in db pointers that are
-** NULL or which have been previously closed.  If this routine returns
-** 1 it means that the db pointer is valid and 0 if it should not be
-** dereferenced for any reason.  The calling function should invoke
-** SQLITE_MISUSE immediately.
-**
-** sqlite3SafetyCheckOk() requires that the db pointer be valid for
-** use.  sqlite3SafetyCheckSickOrOk() allows a db pointer that failed to
-** open properly and is not fit for general use but which can be
-** used as an argument to sqlite3_errmsg() or sqlite3_close().
-*/
-SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3 *db){
-  u32 magic;
-  if( db==0 ){
-    logBadConnection("NULL");
-    return 0;
-  }
-  magic = db->magic;
-  if( magic!=SQLITE_MAGIC_OPEN ){
-    if( sqlite3SafetyCheckSickOrOk(db) ){
-      testcase( sqlite3GlobalConfig.xLog!=0 );
-      logBadConnection("unopened");
-    }
-    return 0;
-  }else{
-    return 1;
-  }
-}
-SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
-  u32 magic;
-  magic = db->magic;
-  if( magic!=SQLITE_MAGIC_SICK &&
-      magic!=SQLITE_MAGIC_OPEN &&
-      magic!=SQLITE_MAGIC_BUSY ){
-    testcase( sqlite3GlobalConfig.xLog!=0 );
-    logBadConnection("invalid");
-    return 0;
-  }else{
-    return 1;
-  }
-}
-
-/*
-** Attempt to add, substract, or multiply the 64-bit signed value iB against
-** the other 64-bit signed integer at *pA and store the result in *pA.
-** Return 0 on success.  Or if the operation would have resulted in an
-** overflow, leave *pA unchanged and return 1.
-*/
-SQLITE_PRIVATE int sqlite3AddInt64(i64 *pA, i64 iB){
-  i64 iA = *pA;
-  testcase( iA==0 ); testcase( iA==1 );
-  testcase( iB==-1 ); testcase( iB==0 );
-  if( iB>=0 ){
-    testcase( iA>0 && LARGEST_INT64 - iA == iB );
-    testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
-    if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;
-    *pA += iB;
-  }else{
-    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
-    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
-    if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;
-    *pA += iB;
-  }
-  return 0; 
-}
-SQLITE_PRIVATE int sqlite3SubInt64(i64 *pA, i64 iB){
-  testcase( iB==SMALLEST_INT64+1 );
-  if( iB==SMALLEST_INT64 ){
-    testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
-    if( (*pA)>=0 ) return 1;
-    *pA -= iB;
-    return 0;
-  }else{
-    return sqlite3AddInt64(pA, -iB);
-  }
-}
-#define TWOPOWER32 (((i64)1)<<32)
-#define TWOPOWER31 (((i64)1)<<31)
-SQLITE_PRIVATE int sqlite3MulInt64(i64 *pA, i64 iB){
-  i64 iA = *pA;
-  i64 iA1, iA0, iB1, iB0, r;
-
-  iA1 = iA/TWOPOWER32;
-  iA0 = iA % TWOPOWER32;
-  iB1 = iB/TWOPOWER32;
-  iB0 = iB % TWOPOWER32;
-  if( iA1*iB1 != 0 ) return 1;
-  assert( iA1*iB0==0 || iA0*iB1==0 );
-  r = iA1*iB0 + iA0*iB1;
-  testcase( r==(-TWOPOWER31)-1 );
-  testcase( r==(-TWOPOWER31) );
-  testcase( r==TWOPOWER31 );
-  testcase( r==TWOPOWER31-1 );
-  if( r<(-TWOPOWER31) || r>=TWOPOWER31 ) return 1;
-  r *= TWOPOWER32;
-  if( sqlite3AddInt64(&r, iA0*iB0) ) return 1;
-  *pA = r;
-  return 0;
-}
-
-/*
-** Compute the absolute value of a 32-bit signed integer, of possible.  Or 
-** if the integer has a value of -2147483648, return +2147483647
-*/
-SQLITE_PRIVATE int sqlite3AbsInt32(int x){
-  if( x>=0 ) return x;
-  if( x==(int)0x80000000 ) return 0x7fffffff;
-  return -x;
-}
-
-#ifdef SQLITE_ENABLE_8_3_NAMES
-/*
-** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database
-** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
-** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
-** three characters, then shorten the suffix on z[] to be the last three
-** characters of the original suffix.
-**
-** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always
-** do the suffix shortening regardless of URI parameter.
-**
-** Examples:
-**
-**     test.db-journal    =>   test.nal
-**     test.db-wal        =>   test.wal
-**     test.db-shm        =>   test.shm
-**     test.db-mj7f3319fa =>   test.9fa
-*/
-SQLITE_PRIVATE void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
-#if SQLITE_ENABLE_8_3_NAMES<2
-  if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) )
-#endif
-  {
-    int i, sz;
-    sz = sqlite3Strlen30(z);
-    for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
-    if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
-  }
-}
-#endif
-
-/* 
-** Find (an approximate) sum of two LogEst values.  This computation is
-** not a simple "+" operator because LogEst is stored as a logarithmic
-** value.
-** 
-*/
-SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
-  static const unsigned char x[] = {
-     10, 10,                         /* 0,1 */
-      9, 9,                          /* 2,3 */
-      8, 8,                          /* 4,5 */
-      7, 7, 7,                       /* 6,7,8 */
-      6, 6, 6,                       /* 9,10,11 */
-      5, 5, 5,                       /* 12-14 */
-      4, 4, 4, 4,                    /* 15-18 */
-      3, 3, 3, 3, 3, 3,              /* 19-24 */
-      2, 2, 2, 2, 2, 2, 2,           /* 25-31 */
-  };
-  if( a>=b ){
-    if( a>b+49 ) return a;
-    if( a>b+31 ) return a+1;
-    return a+x[a-b];
-  }else{
-    if( b>a+49 ) return b;
-    if( b>a+31 ) return b+1;
-    return b+x[b-a];
-  }
-}
-
-/*
-** Convert an integer into a LogEst.  In other words, compute a
-** good approximatation for 10*log2(x).
-*/
-SQLITE_PRIVATE LogEst sqlite3LogEst(u64 x){
-  static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
-  LogEst y = 40;
-  if( x<8 ){
-    if( x<2 ) return 0;
-    while( x<8 ){  y -= 10; x <<= 1; }
-  }else{
-    while( x>255 ){ y += 40; x >>= 4; }
-    while( x>15 ){  y += 10; x >>= 1; }
-  }
-  return a[x&7] + y - 10;
-}
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/*
-** Convert a double into a LogEst
-** In other words, compute an approximation for 10*log2(x).
-*/
-SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double x){
-  u64 a;
-  LogEst e;
-  assert( sizeof(x)==8 && sizeof(a)==8 );
-  if( x<=1 ) return 0;
-  if( x<=2000000000 ) return sqlite3LogEst((u64)x);
-  memcpy(&a, &x, 8);
-  e = (a>>52) - 1022;
-  return e*10;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-/*
-** Convert a LogEst into an integer.
-*/
-SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst x){
-  u64 n;
-  if( x<10 ) return 1;
-  n = x%10;
-  x /= 10;
-  if( n>=5 ) n -= 2;
-  else if( n>=1 ) n -= 1;
-  if( x>=3 ) return (n+8)<<(x-3);
-  return (n+8)>>(3-x);
-}
-
-/************** End of util.c ************************************************/
-/************** Begin file hash.c ********************************************/
-/*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the implementation of generic hash-tables
-** used in SQLite.
-*/
-/* #include <assert.h> */
-
-/* Turn bulk memory into a hash table object by initializing the
-** fields of the Hash structure.
-**
-** "pNew" is a pointer to the hash table that is to be initialized.
-*/
-SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew){
-  assert( pNew!=0 );
-  pNew->first = 0;
-  pNew->count = 0;
-  pNew->htsize = 0;
-  pNew->ht = 0;
-}
-
-/* Remove all entries from a hash table.  Reclaim all memory.
-** Call this routine to delete a hash table or to reset a hash table
-** to the empty state.
-*/
-SQLITE_PRIVATE void sqlite3HashClear(Hash *pH){
-  HashElem *elem;         /* For looping over all elements of the table */
-
-  assert( pH!=0 );
-  elem = pH->first;
-  pH->first = 0;
-  sqlite3_free(pH->ht);
-  pH->ht = 0;
-  pH->htsize = 0;
-  while( elem ){
-    HashElem *next_elem = elem->next;
-    sqlite3_free(elem);
-    elem = next_elem;
-  }
-  pH->count = 0;
-}
-
-/*
-** The hashing function.
-*/
-static unsigned int strHash(const char *z, int nKey){
-  int h = 0;
-  assert( nKey>=0 );
-  while( nKey > 0  ){
-    h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
-    nKey--;
-  }
-  return h;
-}
-
-
-/* Link pNew element into the hash table pH.  If pEntry!=0 then also
-** insert pNew into the pEntry hash bucket.
-*/
-static void insertElement(
-  Hash *pH,              /* The complete hash table */
-  struct _ht *pEntry,    /* The entry into which pNew is inserted */
-  HashElem *pNew         /* The element to be inserted */
-){
-  HashElem *pHead;       /* First element already in pEntry */
-  if( pEntry ){
-    pHead = pEntry->count ? pEntry->chain : 0;
-    pEntry->count++;
-    pEntry->chain = pNew;
-  }else{
-    pHead = 0;
-  }
-  if( pHead ){
-    pNew->next = pHead;
-    pNew->prev = pHead->prev;
-    if( pHead->prev ){ pHead->prev->next = pNew; }
-    else             { pH->first = pNew; }
-    pHead->prev = pNew;
-  }else{
-    pNew->next = pH->first;
-    if( pH->first ){ pH->first->prev = pNew; }
-    pNew->prev = 0;
-    pH->first = pNew;
-  }
-}
-
-
-/* Resize the hash table so that it cantains "new_size" buckets.
-**
-** The hash table might fail to resize if sqlite3_malloc() fails or
-** if the new size is the same as the prior size.
-** Return TRUE if the resize occurs and false if not.
-*/
-static int rehash(Hash *pH, unsigned int new_size){
-  struct _ht *new_ht;            /* The new hash table */
-  HashElem *elem, *next_elem;    /* For looping over existing elements */
-
-#if SQLITE_MALLOC_SOFT_LIMIT>0
-  if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
-    new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
-  }
-  if( new_size==pH->htsize ) return 0;
-#endif
-
-  /* The inability to allocates space for a larger hash table is
-  ** a performance hit but it is not a fatal error.  So mark the
-  ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of 
-  ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
-  ** only zeroes the requested number of bytes whereas this module will
-  ** use the actual amount of space allocated for the hash table (which
-  ** may be larger than the requested amount).
-  */
-  sqlite3BeginBenignMalloc();
-  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
-  sqlite3EndBenignMalloc();
-
-  if( new_ht==0 ) return 0;
-  sqlite3_free(pH->ht);
-  pH->ht = new_ht;
-  pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
-  memset(new_ht, 0, new_size*sizeof(struct _ht));
-  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
-    unsigned int h = strHash(elem->pKey, elem->nKey) % new_size;
-    next_elem = elem->next;
-    insertElement(pH, &new_ht[h], elem);
-  }
-  return 1;
-}
-
-/* This function (for internal use only) locates an element in an
-** hash table that matches the given key.  The hash for this key has
-** already been computed and is passed as the 4th parameter.
-*/
-static HashElem *findElementGivenHash(
-  const Hash *pH,     /* The pH to be searched */
-  const char *pKey,   /* The key we are searching for */
-  int nKey,           /* Bytes in key (not counting zero terminator) */
-  unsigned int h      /* The hash for this key. */
-){
-  HashElem *elem;                /* Used to loop thru the element list */
-  int count;                     /* Number of elements left to test */
-
-  if( pH->ht ){
-    struct _ht *pEntry = &pH->ht[h];
-    elem = pEntry->chain;
-    count = pEntry->count;
-  }else{
-    elem = pH->first;
-    count = pH->count;
-  }
-  while( count-- && ALWAYS(elem) ){
-    if( elem->nKey==nKey && sqlite3StrNICmp(elem->pKey,pKey,nKey)==0 ){ 
-      return elem;
-    }
-    elem = elem->next;
-  }
-  return 0;
-}
-
-/* Remove a single entry from the hash table given a pointer to that
-** element and a hash on the element's key.
-*/
-static void removeElementGivenHash(
-  Hash *pH,         /* The pH containing "elem" */
-  HashElem* elem,   /* The element to be removed from the pH */
-  unsigned int h    /* Hash value for the element */
-){
-  struct _ht *pEntry;
-  if( elem->prev ){
-    elem->prev->next = elem->next; 
-  }else{
-    pH->first = elem->next;
-  }
-  if( elem->next ){
-    elem->next->prev = elem->prev;
-  }
-  if( pH->ht ){
-    pEntry = &pH->ht[h];
-    if( pEntry->chain==elem ){
-      pEntry->chain = elem->next;
-    }
-    pEntry->count--;
-    assert( pEntry->count>=0 );
-  }
-  sqlite3_free( elem );
-  pH->count--;
-  if( pH->count==0 ){
-    assert( pH->first==0 );
-    assert( pH->count==0 );
-    sqlite3HashClear(pH);
-  }
-}
-
-/* Attempt to locate an element of the hash table pH with a key
-** that matches pKey,nKey.  Return the data for this element if it is
-** found, or NULL if there is no match.
-*/
-SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const char *pKey, int nKey){
-  HashElem *elem;    /* The element that matches key */
-  unsigned int h;    /* A hash on key */
-
-  assert( pH!=0 );
-  assert( pKey!=0 );
-  assert( nKey>=0 );
-  if( pH->ht ){
-    h = strHash(pKey, nKey) % pH->htsize;
-  }else{
-    h = 0;
-  }
-  elem = findElementGivenHash(pH, pKey, nKey, h);
-  return elem ? elem->data : 0;
-}
-
-/* Insert an element into the hash table pH.  The key is pKey,nKey
-** and the data is "data".
-**
-** If no element exists with a matching key, then a new
-** element is created and NULL is returned.
-**
-** If another element already exists with the same key, then the
-** new data replaces the old data and the old data is returned.
-** The key is not copied in this instance.  If a malloc fails, then
-** the new data is returned and the hash table is unchanged.
-**
-** If the "data" parameter to this function is NULL, then the
-** element corresponding to "key" is removed from the hash table.
-*/
-SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){
-  unsigned int h;       /* the hash of the key modulo hash table size */
-  HashElem *elem;       /* Used to loop thru the element list */
-  HashElem *new_elem;   /* New element added to the pH */
-
-  assert( pH!=0 );
-  assert( pKey!=0 );
-  assert( nKey>=0 );
-  if( pH->htsize ){
-    h = strHash(pKey, nKey) % pH->htsize;
-  }else{
-    h = 0;
-  }
-  elem = findElementGivenHash(pH,pKey,nKey,h);
-  if( elem ){
-    void *old_data = elem->data;
-    if( data==0 ){
-      removeElementGivenHash(pH,elem,h);
-    }else{
-      elem->data = data;
-      elem->pKey = pKey;
-      assert(nKey==elem->nKey);
-    }
-    return old_data;
-  }
-  if( data==0 ) return 0;
-  new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
-  if( new_elem==0 ) return data;
-  new_elem->pKey = pKey;
-  new_elem->nKey = nKey;
-  new_elem->data = data;
-  pH->count++;
-  if( pH->count>=10 && pH->count > 2*pH->htsize ){
-    if( rehash(pH, pH->count*2) ){
-      assert( pH->htsize>0 );
-      h = strHash(pKey, nKey) % pH->htsize;
-    }
-  }
-  if( pH->ht ){
-    insertElement(pH, &pH->ht[h], new_elem);
-  }else{
-    insertElement(pH, 0, new_elem);
-  }
-  return 0;
-}
-
-/************** End of hash.c ************************************************/
-/************** Begin file opcodes.c *****************************************/
-/* Automatically generated.  Do not edit */
-/* See the mkopcodec.awk script for details. */
-#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
-SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
- static const char *const azName[] = { "?",
-     /*   1 */ "Function",
-     /*   2 */ "Savepoint",
-     /*   3 */ "AutoCommit",
-     /*   4 */ "Transaction",
-     /*   5 */ "SorterNext",
-     /*   6 */ "Prev",
-     /*   7 */ "Next",
-     /*   8 */ "AggStep",
-     /*   9 */ "Checkpoint",
-     /*  10 */ "JournalMode",
-     /*  11 */ "Vacuum",
-     /*  12 */ "VFilter",
-     /*  13 */ "VUpdate",
-     /*  14 */ "Goto",
-     /*  15 */ "Gosub",
-     /*  16 */ "Return",
-     /*  17 */ "Yield",
-     /*  18 */ "HaltIfNull",
-     /*  19 */ "Not",
-     /*  20 */ "Halt",
-     /*  21 */ "Integer",
-     /*  22 */ "Int64",
-     /*  23 */ "String",
-     /*  24 */ "Null",
-     /*  25 */ "Blob",
-     /*  26 */ "Variable",
-     /*  27 */ "Move",
-     /*  28 */ "Copy",
-     /*  29 */ "SCopy",
-     /*  30 */ "ResultRow",
-     /*  31 */ "CollSeq",
-     /*  32 */ "AddImm",
-     /*  33 */ "MustBeInt",
-     /*  34 */ "RealAffinity",
-     /*  35 */ "Permutation",
-     /*  36 */ "Compare",
-     /*  37 */ "Jump",
-     /*  38 */ "Once",
-     /*  39 */ "If",
-     /*  40 */ "IfNot",
-     /*  41 */ "Column",
-     /*  42 */ "Affinity",
-     /*  43 */ "MakeRecord",
-     /*  44 */ "Count",
-     /*  45 */ "ReadCookie",
-     /*  46 */ "SetCookie",
-     /*  47 */ "VerifyCookie",
-     /*  48 */ "OpenRead",
-     /*  49 */ "OpenWrite",
-     /*  50 */ "OpenAutoindex",
-     /*  51 */ "OpenEphemeral",
-     /*  52 */ "SorterOpen",
-     /*  53 */ "OpenPseudo",
-     /*  54 */ "Close",
-     /*  55 */ "SeekLt",
-     /*  56 */ "SeekLe",
-     /*  57 */ "SeekGe",
-     /*  58 */ "SeekGt",
-     /*  59 */ "Seek",
-     /*  60 */ "NotFound",
-     /*  61 */ "Found",
-     /*  62 */ "IsUnique",
-     /*  63 */ "NotExists",
-     /*  64 */ "Sequence",
-     /*  65 */ "NewRowid",
-     /*  66 */ "Insert",
-     /*  67 */ "InsertInt",
-     /*  68 */ "Or",
-     /*  69 */ "And",
-     /*  70 */ "Delete",
-     /*  71 */ "ResetCount",
-     /*  72 */ "SorterCompare",
-     /*  73 */ "IsNull",
-     /*  74 */ "NotNull",
-     /*  75 */ "Ne",
-     /*  76 */ "Eq",
-     /*  77 */ "Gt",
-     /*  78 */ "Le",
-     /*  79 */ "Lt",
-     /*  80 */ "Ge",
-     /*  81 */ "SorterData",
-     /*  82 */ "BitAnd",
-     /*  83 */ "BitOr",
-     /*  84 */ "ShiftLeft",
-     /*  85 */ "ShiftRight",
-     /*  86 */ "Add",
-     /*  87 */ "Subtract",
-     /*  88 */ "Multiply",
-     /*  89 */ "Divide",
-     /*  90 */ "Remainder",
-     /*  91 */ "Concat",
-     /*  92 */ "RowKey",
-     /*  93 */ "BitNot",
-     /*  94 */ "String8",
-     /*  95 */ "RowData",
-     /*  96 */ "Rowid",
-     /*  97 */ "NullRow",
-     /*  98 */ "Last",
-     /*  99 */ "SorterSort",
-     /* 100 */ "Sort",
-     /* 101 */ "Rewind",
-     /* 102 */ "SorterInsert",
-     /* 103 */ "IdxInsert",
-     /* 104 */ "IdxDelete",
-     /* 105 */ "IdxRowid",
-     /* 106 */ "IdxLT",
-     /* 107 */ "IdxGE",
-     /* 108 */ "Destroy",
-     /* 109 */ "Clear",
-     /* 110 */ "CreateIndex",
-     /* 111 */ "CreateTable",
-     /* 112 */ "ParseSchema",
-     /* 113 */ "LoadAnalysis",
-     /* 114 */ "DropTable",
-     /* 115 */ "DropIndex",
-     /* 116 */ "DropTrigger",
-     /* 117 */ "IntegrityCk",
-     /* 118 */ "RowSetAdd",
-     /* 119 */ "RowSetRead",
-     /* 120 */ "RowSetTest",
-     /* 121 */ "Program",
-     /* 122 */ "Param",
-     /* 123 */ "FkCounter",
-     /* 124 */ "FkIfZero",
-     /* 125 */ "MemMax",
-     /* 126 */ "IfPos",
-     /* 127 */ "IfNeg",
-     /* 128 */ "IfZero",
-     /* 129 */ "AggFinal",
-     /* 130 */ "Real",
-     /* 131 */ "IncrVacuum",
-     /* 132 */ "Expire",
-     /* 133 */ "TableLock",
-     /* 134 */ "VBegin",
-     /* 135 */ "VCreate",
-     /* 136 */ "VDestroy",
-     /* 137 */ "VOpen",
-     /* 138 */ "VColumn",
-     /* 139 */ "VNext",
-     /* 140 */ "VRename",
-     /* 141 */ "ToText",
-     /* 142 */ "ToBlob",
-     /* 143 */ "ToNumeric",
-     /* 144 */ "ToInt",
-     /* 145 */ "ToReal",
-     /* 146 */ "Pagecount",
-     /* 147 */ "MaxPgcnt",
-     /* 148 */ "Trace",
-     /* 149 */ "Noop",
-     /* 150 */ "Explain",
-  };
-  return azName[i];
-}
-#endif
-
-/************** End of opcodes.c *********************************************/
-/************** Begin file os_unix.c *****************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains the VFS implementation for unix-like operating systems
-** include Linux, MacOSX, *BSD, QNX, VxWorks, AIX, HPUX, and others.
-**
-** There are actually several different VFS implementations in this file.
-** The differences are in the way that file locking is done.  The default
-** implementation uses Posix Advisory Locks.  Alternative implementations
-** use flock(), dot-files, various proprietary locking schemas, or simply
-** skip locking all together.
-**
-** This source file is organized into divisions where the logic for various
-** subfunctions is contained within the appropriate division.  PLEASE
-** KEEP THE STRUCTURE OF THIS FILE INTACT.  New code should be placed
-** in the correct division and should be clearly labeled.
-**
-** The layout of divisions is as follows:
-**
-**   *  General-purpose declarations and utility functions.
-**   *  Unique file ID logic used by VxWorks.
-**   *  Various locking primitive implementations (all except proxy locking):
-**      + for Posix Advisory Locks
-**      + for no-op locks
-**      + for dot-file locks
-**      + for flock() locking
-**      + for named semaphore locks (VxWorks only)
-**      + for AFP filesystem locks (MacOSX only)
-**   *  sqlite3_file methods not associated with locking.
-**   *  Definitions of sqlite3_io_methods objects for all locking
-**      methods plus "finder" functions for each locking method.
-**   *  sqlite3_vfs method implementations.
-**   *  Locking primitives for the proxy uber-locking-method. (MacOSX only)
-**   *  Definitions of sqlite3_vfs objects for all locking methods
-**      plus implementations of sqlite3_os_init() and sqlite3_os_end().
-*/
-#if SQLITE_OS_UNIX              /* This file is used on unix only */
-
-/*
-** There are various methods for file locking used for concurrency
-** control:
-**
-**   1. POSIX locking (the default),
-**   2. No locking,
-**   3. Dot-file locking,
-**   4. flock() locking,
-**   5. AFP locking (OSX only),
-**   6. Named POSIX semaphores (VXWorks only),
-**   7. proxy locking. (OSX only)
-**
-** Styles 4, 5, and 7 are only available of SQLITE_ENABLE_LOCKING_STYLE
-** is defined to 1.  The SQLITE_ENABLE_LOCKING_STYLE also enables automatic
-** selection of the appropriate locking style based on the filesystem
-** where the database is located.  
-*/
-#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
-#  if defined(__APPLE__)
-#    define SQLITE_ENABLE_LOCKING_STYLE 1
-#  else
-#    define SQLITE_ENABLE_LOCKING_STYLE 0
-#  endif
-#endif
-
-/*
-** Define the OS_VXWORKS pre-processor macro to 1 if building on 
-** vxworks, or 0 otherwise.
-*/
-#ifndef OS_VXWORKS
-#  if defined(__RTP__) || defined(_WRS_KERNEL)
-#    define OS_VXWORKS 1
-#  else
-#    define OS_VXWORKS 0
-#  endif
-#endif
-
-/*
-** These #defines should enable >2GB file support on Posix if the
-** underlying operating system supports it.  If the OS lacks
-** large file support, these should be no-ops.
-**
-** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
-** on the compiler command line.  This is necessary if you are compiling
-** on a recent machine (ex: RedHat 7.2) but you want your code to work
-** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
-** without this option, LFS is enable.  But LFS does not exist in the kernel
-** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
-** portability you should omit LFS.
-**
-** The previous paragraph was written in 2005.  (This paragraph is written
-** on 2008-11-28.) These days, all Linux kernels support large files, so
-** you should probably leave LFS enabled.  But some embedded platforms might
-** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
-*/
-#ifndef SQLITE_DISABLE_LFS
-# define _LARGE_FILE       1
-# ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-# endif
-# define _LARGEFILE_SOURCE 1
-#endif
-
-/*
-** standard include files.
-*/
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-/* #include <time.h> */
-#include <sys/time.h>
-#include <errno.h>
-#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
-#include <sys/mman.h>
-#endif
-
-
-#if SQLITE_ENABLE_LOCKING_STYLE
-# include <sys/ioctl.h>
-# if OS_VXWORKS
-#  include <semaphore.h>
-#  include <limits.h>
-# else
-#  include <sys/file.h>
-#  include <sys/param.h>
-# endif
-#endif /* SQLITE_ENABLE_LOCKING_STYLE */
-
-#if defined(__APPLE__) || (SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS)
-# include <sys/mount.h>
-#endif
-
-#ifdef HAVE_UTIME
-# include <utime.h>
-#endif
-
-/*
-** Allowed values of unixFile.fsFlags
-*/
-#define SQLITE_FSFLAGS_IS_MSDOS     0x1
-
-/*
-** If we are to be thread-safe, include the pthreads header and define
-** the SQLITE_UNIX_THREADS macro.
-*/
-#if SQLITE_THREADSAFE
-/* # include <pthread.h> */
-# define SQLITE_UNIX_THREADS 1
-#endif
-
-/*
-** Default permissions when creating a new file
-*/
-#ifndef SQLITE_DEFAULT_FILE_PERMISSIONS
-# define SQLITE_DEFAULT_FILE_PERMISSIONS 0644
-#endif
-
-/*
-** Default permissions when creating auto proxy dir
-*/
-#ifndef SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
-# define SQLITE_DEFAULT_PROXYDIR_PERMISSIONS 0755
-#endif
-
-/*
-** Maximum supported path-length.
-*/
-#define MAX_PATHNAME 512
-
-/*
-** Only set the lastErrno if the error code is a real error and not 
-** a normal expected return code of SQLITE_BUSY or SQLITE_OK
-*/
-#define IS_LOCK_ERROR(x)  ((x != SQLITE_OK) && (x != SQLITE_BUSY))
-
-/* Forward references */
-typedef struct unixShm unixShm;               /* Connection shared memory */
-typedef struct unixShmNode unixShmNode;       /* Shared memory instance */
-typedef struct unixInodeInfo unixInodeInfo;   /* An i-node */
-typedef struct UnixUnusedFd UnixUnusedFd;     /* An unused file descriptor */
-
-/*
-** Sometimes, after a file handle is closed by SQLite, the file descriptor
-** cannot be closed immediately. In these cases, instances of the following
-** structure are used to store the file descriptor while waiting for an
-** opportunity to either close or reuse it.
-*/
-struct UnixUnusedFd {
-  int fd;                   /* File descriptor to close */
-  int flags;                /* Flags this file descriptor was opened with */
-  UnixUnusedFd *pNext;      /* Next unused file descriptor on same file */
-};
-
-/*
-** The unixFile structure is subclass of sqlite3_file specific to the unix
-** VFS implementations.
-*/
-typedef struct unixFile unixFile;
-struct unixFile {
-  sqlite3_io_methods const *pMethod;  /* Always the first entry */
-  sqlite3_vfs *pVfs;                  /* The VFS that created this unixFile */
-  unixInodeInfo *pInode;              /* Info about locks on this inode */
-  int h;                              /* The file descriptor */
-  unsigned char eFileLock;            /* The type of lock held on this fd */
-  unsigned short int ctrlFlags;       /* Behavioral bits.  UNIXFILE_* flags */
-  int lastErrno;                      /* The unix errno from last I/O error */
-  void *lockingContext;               /* Locking style specific state */
-  UnixUnusedFd *pUnused;              /* Pre-allocated UnixUnusedFd */
-  const char *zPath;                  /* Name of the file */
-  unixShm *pShm;                      /* Shared memory segment information */
-  int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
-#if SQLITE_MAX_MMAP_SIZE>0
-  int nFetchOut;                      /* Number of outstanding xFetch refs */
-  sqlite3_int64 mmapSize;             /* Usable size of mapping at pMapRegion */
-  sqlite3_int64 mmapSizeActual;       /* Actual size of mapping at pMapRegion */
-  sqlite3_int64 mmapSizeMax;          /* Configured FCNTL_MMAP_SIZE value */
-  void *pMapRegion;                   /* Memory mapped region */
-#endif
-#ifdef __QNXNTO__
-  int sectorSize;                     /* Device sector size */
-  int deviceCharacteristics;          /* Precomputed device characteristics */
-#endif
-#if SQLITE_ENABLE_LOCKING_STYLE
-  int openFlags;                      /* The flags specified at open() */
-#endif
-#if SQLITE_ENABLE_LOCKING_STYLE || defined(__APPLE__)
-  unsigned fsFlags;                   /* cached details from statfs() */
-#endif
-#if OS_VXWORKS
-  struct vxworksFileId *pId;          /* Unique file ID */
-#endif
-#ifdef SQLITE_DEBUG
-  /* The next group of variables are used to track whether or not the
-  ** transaction counter in bytes 24-27 of database files are updated
-  ** whenever any part of the database changes.  An assertion fault will
-  ** occur if a file is updated without also updating the transaction
-  ** counter.  This test is made to avoid new problems similar to the
-  ** one described by ticket #3584. 
-  */
-  unsigned char transCntrChng;   /* True if the transaction counter changed */
-  unsigned char dbUpdate;        /* True if any part of database file changed */
-  unsigned char inNormalWrite;   /* True if in a normal write operation */
-
-#endif
-
-#ifdef SQLITE_TEST
-  /* In test mode, increase the size of this structure a bit so that 
-  ** it is larger than the struct CrashFile defined in test6.c.
-  */
-  char aPadding[32];
-#endif
-};
-
-/*
-** Allowed values for the unixFile.ctrlFlags bitmask:
-*/
-#define UNIXFILE_EXCL        0x01     /* Connections from one process only */
-#define UNIXFILE_RDONLY      0x02     /* Connection is read only */
-#define UNIXFILE_PERSIST_WAL 0x04     /* Persistent WAL mode */
-#ifndef SQLITE_DISABLE_DIRSYNC
-# define UNIXFILE_DIRSYNC    0x08     /* Directory sync needed */
-#else
-# define UNIXFILE_DIRSYNC    0x00
-#endif
-#define UNIXFILE_PSOW        0x10     /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
-#define UNIXFILE_DELETE      0x20     /* Delete on close */
-#define UNIXFILE_URI         0x40     /* Filename might have query parameters */
-#define UNIXFILE_NOLOCK      0x80     /* Do no file locking */
-#define UNIXFILE_WARNED    0x0100     /* verifyDbFile() warnings have been issued */
-
-/*
-** Include code that is common to all os_*.c files
-*/
-/************** Include os_common.h in the middle of os_unix.c ***************/
-/************** Begin file os_common.h ***************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains macros and a little bit of code that is common to
-** all of the platform-specific files (os_*.c) and is #included into those
-** files.
-**
-** This file should be #included by the os_*.c files only.  It is not a
-** general purpose header file.
-*/
-#ifndef _OS_COMMON_H_
-#define _OS_COMMON_H_
-
-/*
-** At least two bugs have slipped in because we changed the MEMORY_DEBUG
-** macro to SQLITE_DEBUG and some older makefiles have not yet made the
-** switch.  The following code should catch this problem at compile-time.
-*/
-#ifdef MEMORY_DEBUG
-# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
-#endif
-
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-# ifndef SQLITE_DEBUG_OS_TRACE
-#   define SQLITE_DEBUG_OS_TRACE 0
-# endif
-  int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
-# define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
-#else
-# define OSTRACE(X)
-#endif
-
-/*
-** Macros for performance tracing.  Normally turned off.  Only works
-** on i486 hardware.
-*/
-#ifdef SQLITE_PERFORMANCE_TRACE
-
-/* 
-** hwtime.h contains inline assembler code for implementing 
-** high-performance timing routines.
-*/
-/************** Include hwtime.h in the middle of os_common.h ****************/
-/************** Begin file hwtime.h ******************************************/
-/*
-** 2008 May 27
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains inline asm code for retrieving "high-performance"
-** counters for x86 class CPUs.
-*/
-#ifndef _HWTIME_H_
-#define _HWTIME_H_
-
-/*
-** The following routine only works on pentium-class (or newer) processors.
-** It uses the RDTSC opcode to read the cycle count value out of the
-** processor and returns that value.  This can be used for high-res
-** profiling.
-*/
-#if (defined(__GNUC__) || defined(_MSC_VER)) && \
-      (defined(i386) || defined(__i386__) || defined(_M_IX86))
-
-  #if defined(__GNUC__)
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-     unsigned int lo, hi;
-     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
-     return (sqlite_uint64)hi << 32 | lo;
-  }
-
-  #elif defined(_MSC_VER)
-
-  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
-     __asm {
-        rdtsc
-        ret       ; return value at EDX:EAX
-     }
-  }
-
-  #endif
-
-#elif (defined(__GNUC__) && defined(__x86_64__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long val;
-      __asm__ __volatile__ ("rdtsc" : "=A" (val));
-      return val;
-  }
- 
-#elif (defined(__GNUC__) && defined(__ppc__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long long retval;
-      unsigned long junk;
-      __asm__ __volatile__ ("\n\
-          1:      mftbu   %1\n\
-                  mftb    %L0\n\
-                  mftbu   %0\n\
-                  cmpw    %0,%1\n\
-                  bne     1b"
-                  : "=r" (retval), "=r" (junk));
-      return retval;
-  }
-
-#else
-
-  #error Need implementation of sqlite3Hwtime() for your platform.
-
-  /*
-  ** To compile without implementing sqlite3Hwtime() for your platform,
-  ** you can remove the above #error and use the following
-  ** stub function.  You will lose timing support for many
-  ** of the debugging and testing utilities, but it should at
-  ** least compile and run.
-  */
-SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
-
-#endif
-
-#endif /* !defined(_HWTIME_H_) */
-
-/************** End of hwtime.h **********************************************/
-/************** Continuing where we left off in os_common.h ******************/
-
-static sqlite_uint64 g_start;
-static sqlite_uint64 g_elapsed;
-#define TIMER_START       g_start=sqlite3Hwtime()
-#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
-#define TIMER_ELAPSED     g_elapsed
-#else
-#define TIMER_START
-#define TIMER_END
-#define TIMER_ELAPSED     ((sqlite_uint64)0)
-#endif
-
-/*
-** If we compile with the SQLITE_TEST macro set, then the following block
-** of code will give us the ability to simulate a disk I/O error.  This
-** is used for testing the I/O recovery logic.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
-SQLITE_API int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
-SQLITE_API int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
-SQLITE_API int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
-SQLITE_API int sqlite3_io_error_benign = 0;         /* True if errors are benign */
-SQLITE_API int sqlite3_diskfull_pending = 0;
-SQLITE_API int sqlite3_diskfull = 0;
-#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
-#define SimulateIOError(CODE)  \
-  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
-       || sqlite3_io_error_pending-- == 1 )  \
-              { local_ioerr(); CODE; }
-static void local_ioerr(){
-  IOTRACE(("IOERR\n"));
-  sqlite3_io_error_hit++;
-  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
-}
-#define SimulateDiskfullError(CODE) \
-   if( sqlite3_diskfull_pending ){ \
-     if( sqlite3_diskfull_pending == 1 ){ \
-       local_ioerr(); \
-       sqlite3_diskfull = 1; \
-       sqlite3_io_error_hit = 1; \
-       CODE; \
-     }else{ \
-       sqlite3_diskfull_pending--; \
-     } \
-   }
-#else
-#define SimulateIOErrorBenign(X)
-#define SimulateIOError(A)
-#define SimulateDiskfullError(A)
-#endif
-
-/*
-** When testing, keep a count of the number of open files.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_open_file_count = 0;
-#define OpenCounter(X)  sqlite3_open_file_count+=(X)
-#else
-#define OpenCounter(X)
-#endif
-
-#endif /* !defined(_OS_COMMON_H_) */
-
-/************** End of os_common.h *******************************************/
-/************** Continuing where we left off in os_unix.c ********************/
-
-/*
-** Define various macros that are missing from some systems.
-*/
-#ifndef O_LARGEFILE
-# define O_LARGEFILE 0
-#endif
-#ifdef SQLITE_DISABLE_LFS
-# undef O_LARGEFILE
-# define O_LARGEFILE 0
-#endif
-#ifndef O_NOFOLLOW
-# define O_NOFOLLOW 0
-#endif
-#ifndef O_BINARY
-# define O_BINARY 0
-#endif
-
-/*
-** The threadid macro resolves to the thread-id or to 0.  Used for
-** testing and debugging only.
-*/
-#if SQLITE_THREADSAFE
-#define threadid pthread_self()
-#else
-#define threadid 0
-#endif
-
-/*
-** HAVE_MREMAP defaults to true on Linux and false everywhere else.
-*/
-#if !defined(HAVE_MREMAP)
-# if defined(__linux__) && defined(_GNU_SOURCE)
-#  define HAVE_MREMAP 1
-# else
-#  define HAVE_MREMAP 0
-# endif
-#endif
-
-/*
-** Different Unix systems declare open() in different ways.  Same use
-** open(const char*,int,mode_t).  Others use open(const char*,int,...).
-** The difference is important when using a pointer to the function.
-**
-** The safest way to deal with the problem is to always use this wrapper
-** which always has the same well-defined interface.
-*/
-static int posixOpen(const char *zFile, int flags, int mode){
-  return open(zFile, flags, mode);
-}
-
-/*
-** On some systems, calls to fchown() will trigger a message in a security
-** log if they come from non-root processes.  So avoid calling fchown() if
-** we are not running as root.
-*/
-static int posixFchown(int fd, uid_t uid, gid_t gid){
-  return geteuid() ? 0 : fchown(fd,uid,gid);
-}
-
-/* Forward reference */
-static int openDirectory(const char*, int*);
-
-/*
-** Many system calls are accessed through pointer-to-functions so that
-** they may be overridden at runtime to facilitate fault injection during
-** testing and sandboxing.  The following array holds the names and pointers
-** to all overrideable system calls.
-*/
-static struct unix_syscall {
-  const char *zName;            /* Name of the system call */
-  sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
-  sqlite3_syscall_ptr pDefault; /* Default value */
-} aSyscall[] = {
-  { "open",         (sqlite3_syscall_ptr)posixOpen,  0  },
-#define osOpen      ((int(*)(const char*,int,int))aSyscall[0].pCurrent)
-
-  { "close",        (sqlite3_syscall_ptr)close,      0  },
-#define osClose     ((int(*)(int))aSyscall[1].pCurrent)
-
-  { "access",       (sqlite3_syscall_ptr)access,     0  },
-#define osAccess    ((int(*)(const char*,int))aSyscall[2].pCurrent)
-
-  { "getcwd",       (sqlite3_syscall_ptr)getcwd,     0  },
-#define osGetcwd    ((char*(*)(char*,size_t))aSyscall[3].pCurrent)
-
-  { "stat",         (sqlite3_syscall_ptr)stat,       0  },
-#define osStat      ((int(*)(const char*,struct stat*))aSyscall[4].pCurrent)
-
-/*
-** The DJGPP compiler environment looks mostly like Unix, but it
-** lacks the fcntl() system call.  So redefine fcntl() to be something
-** that always succeeds.  This means that locking does not occur under
-** DJGPP.  But it is DOS - what did you expect?
-*/
-#ifdef __DJGPP__
-  { "fstat",        0,                 0  },
-#define osFstat(a,b,c)    0
-#else     
-  { "fstat",        (sqlite3_syscall_ptr)fstat,      0  },
-#define osFstat     ((int(*)(int,struct stat*))aSyscall[5].pCurrent)
-#endif
-
-  { "ftruncate",    (sqlite3_syscall_ptr)ftruncate,  0  },
-#define osFtruncate ((int(*)(int,off_t))aSyscall[6].pCurrent)
-
-  { "fcntl",        (sqlite3_syscall_ptr)fcntl,      0  },
-#define osFcntl     ((int(*)(int,int,...))aSyscall[7].pCurrent)
-
-  { "read",         (sqlite3_syscall_ptr)read,       0  },
-#define osRead      ((ssize_t(*)(int,void*,size_t))aSyscall[8].pCurrent)
-
-#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
-  { "pread",        (sqlite3_syscall_ptr)pread,      0  },
-#else
-  { "pread",        (sqlite3_syscall_ptr)0,          0  },
-#endif
-#define osPread     ((ssize_t(*)(int,void*,size_t,off_t))aSyscall[9].pCurrent)
-
-#if defined(USE_PREAD64)
-  { "pread64",      (sqlite3_syscall_ptr)pread64,    0  },
-#else
-  { "pread64",      (sqlite3_syscall_ptr)0,          0  },
-#endif
-#define osPread64   ((ssize_t(*)(int,void*,size_t,off_t))aSyscall[10].pCurrent)
-
-  { "write",        (sqlite3_syscall_ptr)write,      0  },
-#define osWrite     ((ssize_t(*)(int,const void*,size_t))aSyscall[11].pCurrent)
-
-#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
-  { "pwrite",       (sqlite3_syscall_ptr)pwrite,     0  },
-#else
-  { "pwrite",       (sqlite3_syscall_ptr)0,          0  },
-#endif
-#define osPwrite    ((ssize_t(*)(int,const void*,size_t,off_t))\
-                    aSyscall[12].pCurrent)
-
-#if defined(USE_PREAD64)
-  { "pwrite64",     (sqlite3_syscall_ptr)pwrite64,   0  },
-#else
-  { "pwrite64",     (sqlite3_syscall_ptr)0,          0  },
-#endif
-#define osPwrite64  ((ssize_t(*)(int,const void*,size_t,off_t))\
-                    aSyscall[13].pCurrent)
-
-  { "fchmod",       (sqlite3_syscall_ptr)fchmod,     0  },
-#define osFchmod    ((int(*)(int,mode_t))aSyscall[14].pCurrent)
-
-#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
-  { "fallocate",    (sqlite3_syscall_ptr)posix_fallocate,  0 },
-#else
-  { "fallocate",    (sqlite3_syscall_ptr)0,                0 },
-#endif
-#define osFallocate ((int(*)(int,off_t,off_t))aSyscall[15].pCurrent)
-
-  { "unlink",       (sqlite3_syscall_ptr)unlink,           0 },
-#define osUnlink    ((int(*)(const char*))aSyscall[16].pCurrent)
-
-  { "openDirectory",    (sqlite3_syscall_ptr)openDirectory,      0 },
-#define osOpenDirectory ((int(*)(const char*,int*))aSyscall[17].pCurrent)
-
-  { "mkdir",        (sqlite3_syscall_ptr)mkdir,           0 },
-#define osMkdir     ((int(*)(const char*,mode_t))aSyscall[18].pCurrent)
-
-  { "rmdir",        (sqlite3_syscall_ptr)rmdir,           0 },
-#define osRmdir     ((int(*)(const char*))aSyscall[19].pCurrent)
-
-  { "fchown",       (sqlite3_syscall_ptr)posixFchown,     0 },
-#define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)
-
-#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
-  { "mmap",       (sqlite3_syscall_ptr)mmap,     0 },
-#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[21].pCurrent)
-
-  { "munmap",       (sqlite3_syscall_ptr)munmap,          0 },
-#define osMunmap ((void*(*)(void*,size_t))aSyscall[22].pCurrent)
-
-#if HAVE_MREMAP
-  { "mremap",       (sqlite3_syscall_ptr)mremap,          0 },
-#else
-  { "mremap",       (sqlite3_syscall_ptr)0,               0 },
-#endif
-#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)
-#endif
-
-}; /* End of the overrideable system calls */
-
-/*
-** This is the xSetSystemCall() method of sqlite3_vfs for all of the
-** "unix" VFSes.  Return SQLITE_OK opon successfully updating the
-** system call pointer, or SQLITE_NOTFOUND if there is no configurable
-** system call named zName.
-*/
-static int unixSetSystemCall(
-  sqlite3_vfs *pNotUsed,        /* The VFS pointer.  Not used */
-  const char *zName,            /* Name of system call to override */
-  sqlite3_syscall_ptr pNewFunc  /* Pointer to new system call value */
-){
-  unsigned int i;
-  int rc = SQLITE_NOTFOUND;
-
-  UNUSED_PARAMETER(pNotUsed);
-  if( zName==0 ){
-    /* If no zName is given, restore all system calls to their default
-    ** settings and return NULL
-    */
-    rc = SQLITE_OK;
-    for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-      if( aSyscall[i].pDefault ){
-        aSyscall[i].pCurrent = aSyscall[i].pDefault;
-      }
-    }
-  }else{
-    /* If zName is specified, operate on only the one system call
-    ** specified.
-    */
-    for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-      if( strcmp(zName, aSyscall[i].zName)==0 ){
-        if( aSyscall[i].pDefault==0 ){
-          aSyscall[i].pDefault = aSyscall[i].pCurrent;
-        }
-        rc = SQLITE_OK;
-        if( pNewFunc==0 ) pNewFunc = aSyscall[i].pDefault;
-        aSyscall[i].pCurrent = pNewFunc;
-        break;
-      }
-    }
-  }
-  return rc;
-}
-
-/*
-** Return the value of a system call.  Return NULL if zName is not a
-** recognized system call name.  NULL is also returned if the system call
-** is currently undefined.
-*/
-static sqlite3_syscall_ptr unixGetSystemCall(
-  sqlite3_vfs *pNotUsed,
-  const char *zName
-){
-  unsigned int i;
-
-  UNUSED_PARAMETER(pNotUsed);
-  for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-    if( strcmp(zName, aSyscall[i].zName)==0 ) return aSyscall[i].pCurrent;
-  }
-  return 0;
-}
-
-/*
-** Return the name of the first system call after zName.  If zName==NULL
-** then return the name of the first system call.  Return NULL if zName
-** is the last system call or if zName is not the name of a valid
-** system call.
-*/
-static const char *unixNextSystemCall(sqlite3_vfs *p, const char *zName){
-  int i = -1;
-
-  UNUSED_PARAMETER(p);
-  if( zName ){
-    for(i=0; i<ArraySize(aSyscall)-1; i++){
-      if( strcmp(zName, aSyscall[i].zName)==0 ) break;
-    }
-  }
-  for(i++; i<ArraySize(aSyscall); i++){
-    if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
-  }
-  return 0;
-}
-
-/*
-** Do not accept any file descriptor less than this value, in order to avoid
-** opening database file using file descriptors that are commonly used for 
-** standard input, output, and error.
-*/
-#ifndef SQLITE_MINIMUM_FILE_DESCRIPTOR
-# define SQLITE_MINIMUM_FILE_DESCRIPTOR 3
-#endif
-
-/*
-** Invoke open().  Do so multiple times, until it either succeeds or
-** fails for some reason other than EINTR.
-**
-** If the file creation mode "m" is 0 then set it to the default for
-** SQLite.  The default is SQLITE_DEFAULT_FILE_PERMISSIONS (normally
-** 0644) as modified by the system umask.  If m is not 0, then
-** make the file creation mode be exactly m ignoring the umask.
-**
-** The m parameter will be non-zero only when creating -wal, -journal,
-** and -shm files.  We want those files to have *exactly* the same
-** permissions as their original database, unadulterated by the umask.
-** In that way, if a database file is -rw-rw-rw or -rw-rw-r-, and a
-** transaction crashes and leaves behind hot journals, then any
-** process that is able to write to the database will also be able to
-** recover the hot journals.
-*/
-static int robust_open(const char *z, int f, mode_t m){
-  int fd;
-  mode_t m2 = m ? m : SQLITE_DEFAULT_FILE_PERMISSIONS;
-  while(1){
-#if defined(O_CLOEXEC)
-    fd = osOpen(z,f|O_CLOEXEC,m2);
-#else
-    fd = osOpen(z,f,m2);
-#endif
-    if( fd<0 ){
-      if( errno==EINTR ) continue;
-      break;
-    }
-    if( fd>=SQLITE_MINIMUM_FILE_DESCRIPTOR ) break;
-    osClose(fd);
-    sqlite3_log(SQLITE_WARNING, 
-                "attempt to open \"%s\" as file descriptor %d", z, fd);
-    fd = -1;
-    if( osOpen("/dev/null", f, m)<0 ) break;
-  }
-  if( fd>=0 ){
-    if( m!=0 ){
-      struct stat statbuf;
-      if( osFstat(fd, &statbuf)==0 
-       && statbuf.st_size==0
-       && (statbuf.st_mode&0777)!=m 
-      ){
-        osFchmod(fd, m);
-      }
-    }
-#if defined(FD_CLOEXEC) && (!defined(O_CLOEXEC) || O_CLOEXEC==0)
-    osFcntl(fd, F_SETFD, osFcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
-#endif
-  }
-  return fd;
-}
-
-/*
-** Helper functions to obtain and relinquish the global mutex. The
-** global mutex is used to protect the unixInodeInfo and
-** vxworksFileId objects used by this file, all of which may be 
-** shared by multiple threads.
-**
-** Function unixMutexHeld() is used to assert() that the global mutex 
-** is held when required. This function is only used as part of assert() 
-** statements. e.g.
-**
-**   unixEnterMutex()
-**     assert( unixMutexHeld() );
-**   unixEnterLeave()
-*/
-static void unixEnterMutex(void){
-  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-static void unixLeaveMutex(void){
-  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-#ifdef SQLITE_DEBUG
-static int unixMutexHeld(void) {
-  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-#endif
-
-
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-/*
-** Helper function for printing out trace information from debugging
-** binaries. This returns the string represetation of the supplied
-** integer lock-type.
-*/
-static const char *azFileLock(int eFileLock){
-  switch( eFileLock ){
-    case NO_LOCK: return "NONE";
-    case SHARED_LOCK: return "SHARED";
-    case RESERVED_LOCK: return "RESERVED";
-    case PENDING_LOCK: return "PENDING";
-    case EXCLUSIVE_LOCK: return "EXCLUSIVE";
-  }
-  return "ERROR";
-}
-#endif
-
-#ifdef SQLITE_LOCK_TRACE
-/*
-** Print out information about all locking operations.
-**
-** This routine is used for troubleshooting locks on multithreaded
-** platforms.  Enable by compiling with the -DSQLITE_LOCK_TRACE
-** command-line option on the compiler.  This code is normally
-** turned off.
-*/
-static int lockTrace(int fd, int op, struct flock *p){
-  char *zOpName, *zType;
-  int s;
-  int savedErrno;
-  if( op==F_GETLK ){
-    zOpName = "GETLK";
-  }else if( op==F_SETLK ){
-    zOpName = "SETLK";
-  }else{
-    s = osFcntl(fd, op, p);
-    sqlite3DebugPrintf("fcntl unknown %d %d %d\n", fd, op, s);
-    return s;
-  }
-  if( p->l_type==F_RDLCK ){
-    zType = "RDLCK";
-  }else if( p->l_type==F_WRLCK ){
-    zType = "WRLCK";
-  }else if( p->l_type==F_UNLCK ){
-    zType = "UNLCK";
-  }else{
-    assert( 0 );
-  }
-  assert( p->l_whence==SEEK_SET );
-  s = osFcntl(fd, op, p);
-  savedErrno = errno;
-  sqlite3DebugPrintf("fcntl %d %d %s %s %d %d %d %d\n",
-     threadid, fd, zOpName, zType, (int)p->l_start, (int)p->l_len,
-     (int)p->l_pid, s);
-  if( s==(-1) && op==F_SETLK && (p->l_type==F_RDLCK || p->l_type==F_WRLCK) ){
-    struct flock l2;
-    l2 = *p;
-    osFcntl(fd, F_GETLK, &l2);
-    if( l2.l_type==F_RDLCK ){
-      zType = "RDLCK";
-    }else if( l2.l_type==F_WRLCK ){
-      zType = "WRLCK";
-    }else if( l2.l_type==F_UNLCK ){
-      zType = "UNLCK";
-    }else{
-      assert( 0 );
-    }
-    sqlite3DebugPrintf("fcntl-failure-reason: %s %d %d %d\n",
-       zType, (int)l2.l_start, (int)l2.l_len, (int)l2.l_pid);
-  }
-  errno = savedErrno;
-  return s;
-}
-#undef osFcntl
-#define osFcntl lockTrace
-#endif /* SQLITE_LOCK_TRACE */
-
-/*
-** Retry ftruncate() calls that fail due to EINTR
-*/
-static int robust_ftruncate(int h, sqlite3_int64 sz){
-  int rc;
-  do{ rc = osFtruncate(h,sz); }while( rc<0 && errno==EINTR );
-  return rc;
-}
-
-/*
-** This routine translates a standard POSIX errno code into something
-** useful to the clients of the sqlite3 functions.  Specifically, it is
-** intended to translate a variety of "try again" errors into SQLITE_BUSY
-** and a variety of "please close the file descriptor NOW" errors into 
-** SQLITE_IOERR
-** 
-** Errors during initialization of locks, or file system support for locks,
-** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
-*/
-static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
-  switch (posixError) {
-#if 0
-  /* At one point this code was not commented out. In theory, this branch
-  ** should never be hit, as this function should only be called after
-  ** a locking-related function (i.e. fcntl()) has returned non-zero with
-  ** the value of errno as the first argument. Since a system call has failed,
-  ** errno should be non-zero.
-  **
-  ** Despite this, if errno really is zero, we still don't want to return
-  ** SQLITE_OK. The system call failed, and *some* SQLite error should be
-  ** propagated back to the caller. Commenting this branch out means errno==0
-  ** will be handled by the "default:" case below.
-  */
-  case 0: 
-    return SQLITE_OK;
-#endif
-
-  case EAGAIN:
-  case ETIMEDOUT:
-  case EBUSY:
-  case EINTR:
-  case ENOLCK:  
-    /* random NFS retry error, unless during file system support 
-     * introspection, in which it actually means what it says */
-    return SQLITE_BUSY;
-    
-  case EACCES: 
-    /* EACCES is like EAGAIN during locking operations, but not any other time*/
-    if( (sqliteIOErr == SQLITE_IOERR_LOCK) || 
-        (sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
-        (sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
-        (sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
-      return SQLITE_BUSY;
-    }
-    /* else fall through */
-  case EPERM: 
-    return SQLITE_PERM;
-    
-  /* EDEADLK is only possible if a call to fcntl(F_SETLKW) is made. And
-  ** this module never makes such a call. And the code in SQLite itself 
-  ** asserts that SQLITE_IOERR_BLOCKED is never returned. For these reasons
-  ** this case is also commented out. If the system does set errno to EDEADLK,
-  ** the default SQLITE_IOERR_XXX code will be returned. */
-#if 0
-  case EDEADLK:
-    return SQLITE_IOERR_BLOCKED;
-#endif
-    
-#if EOPNOTSUPP!=ENOTSUP
-  case EOPNOTSUPP: 
-    /* something went terribly awry, unless during file system support 
-     * introspection, in which it actually means what it says */
-#endif
-#ifdef ENOTSUP
-  case ENOTSUP: 
-    /* invalid fd, unless during file system support introspection, in which 
-     * it actually means what it says */
-#endif
-  case EIO:
-  case EBADF:
-  case EINVAL:
-  case ENOTCONN:
-  case ENODEV:
-  case ENXIO:
-  case ENOENT:
-#ifdef ESTALE                     /* ESTALE is not defined on Interix systems */
-  case ESTALE:
-#endif
-  case ENOSYS:
-    /* these should force the client to close the file and reconnect */
-    
-  default: 
-    return sqliteIOErr;
-  }
-}
-
-
-/******************************************************************************
-****************** Begin Unique File ID Utility Used By VxWorks ***************
-**
-** On most versions of unix, we can get a unique ID for a file by concatenating
-** the device number and the inode number.  But this does not work on VxWorks.
-** On VxWorks, a unique file id must be based on the canonical filename.
-**
-** A pointer to an instance of the following structure can be used as a
-** unique file ID in VxWorks.  Each instance of this structure contains
-** a copy of the canonical filename.  There is also a reference count.  
-** The structure is reclaimed when the number of pointers to it drops to
-** zero.
-**
-** There are never very many files open at one time and lookups are not
-** a performance-critical path, so it is sufficient to put these
-** structures on a linked list.
-*/
-struct vxworksFileId {
-  struct vxworksFileId *pNext;  /* Next in a list of them all */
-  int nRef;                     /* Number of references to this one */
-  int nName;                    /* Length of the zCanonicalName[] string */
-  char *zCanonicalName;         /* Canonical filename */
-};
-
-#if OS_VXWORKS
-/* 
-** All unique filenames are held on a linked list headed by this
-** variable:
-*/
-static struct vxworksFileId *vxworksFileList = 0;
-
-/*
-** Simplify a filename into its canonical form
-** by making the following changes:
-**
-**  * removing any trailing and duplicate /
-**  * convert /./ into just /
-**  * convert /A/../ where A is any simple name into just /
-**
-** Changes are made in-place.  Return the new name length.
-**
-** The original filename is in z[0..n-1].  Return the number of
-** characters in the simplified name.
-*/
-static int vxworksSimplifyName(char *z, int n){
-  int i, j;
-  while( n>1 && z[n-1]=='/' ){ n--; }
-  for(i=j=0; i<n; i++){
-    if( z[i]=='/' ){
-      if( z[i+1]=='/' ) continue;
-      if( z[i+1]=='.' && i+2<n && z[i+2]=='/' ){
-        i += 1;
-        continue;
-      }
-      if( z[i+1]=='.' && i+3<n && z[i+2]=='.' && z[i+3]=='/' ){
-        while( j>0 && z[j-1]!='/' ){ j--; }
-        if( j>0 ){ j--; }
-        i += 2;
-        continue;
-      }
-    }
-    z[j++] = z[i];
-  }
-  z[j] = 0;
-  return j;
-}
-
-/*
-** Find a unique file ID for the given absolute pathname.  Return
-** a pointer to the vxworksFileId object.  This pointer is the unique
-** file ID.
-**
-** The nRef field of the vxworksFileId object is incremented before
-** the object is returned.  A new vxworksFileId object is created
-** and added to the global list if necessary.
-**
-** If a memory allocation error occurs, return NULL.
-*/
-static struct vxworksFileId *vxworksFindFileId(const char *zAbsoluteName){
-  struct vxworksFileId *pNew;         /* search key and new file ID */
-  struct vxworksFileId *pCandidate;   /* For looping over existing file IDs */
-  int n;                              /* Length of zAbsoluteName string */
-
-  assert( zAbsoluteName[0]=='/' );
-  n = (int)strlen(zAbsoluteName);
-  pNew = sqlite3_malloc( sizeof(*pNew) + (n+1) );
-  if( pNew==0 ) return 0;
-  pNew->zCanonicalName = (char*)&pNew[1];
-  memcpy(pNew->zCanonicalName, zAbsoluteName, n+1);
-  n = vxworksSimplifyName(pNew->zCanonicalName, n);
-
-  /* Search for an existing entry that matching the canonical name.
-  ** If found, increment the reference count and return a pointer to
-  ** the existing file ID.
-  */
-  unixEnterMutex();
-  for(pCandidate=vxworksFileList; pCandidate; pCandidate=pCandidate->pNext){
-    if( pCandidate->nName==n 
-     && memcmp(pCandidate->zCanonicalName, pNew->zCanonicalName, n)==0
-    ){
-       sqlite3_free(pNew);
-       pCandidate->nRef++;
-       unixLeaveMutex();
-       return pCandidate;
-    }
-  }
-
-  /* No match was found.  We will make a new file ID */
-  pNew->nRef = 1;
-  pNew->nName = n;
-  pNew->pNext = vxworksFileList;
-  vxworksFileList = pNew;
-  unixLeaveMutex();
-  return pNew;
-}
-
-/*
-** Decrement the reference count on a vxworksFileId object.  Free
-** the object when the reference count reaches zero.
-*/
-static void vxworksReleaseFileId(struct vxworksFileId *pId){
-  unixEnterMutex();
-  assert( pId->nRef>0 );
-  pId->nRef--;
-  if( pId->nRef==0 ){
-    struct vxworksFileId **pp;
-    for(pp=&vxworksFileList; *pp && *pp!=pId; pp = &((*pp)->pNext)){}
-    assert( *pp==pId );
-    *pp = pId->pNext;
-    sqlite3_free(pId);
-  }
-  unixLeaveMutex();
-}
-#endif /* OS_VXWORKS */
-/*************** End of Unique File ID Utility Used By VxWorks ****************
-******************************************************************************/
-
-
-/******************************************************************************
-*************************** Posix Advisory Locking ****************************
-**
-** POSIX advisory locks are broken by design.  ANSI STD 1003.1 (1996)
-** section 6.5.2.2 lines 483 through 490 specify that when a process
-** sets or clears a lock, that operation overrides any prior locks set
-** by the same process.  It does not explicitly say so, but this implies
-** that it overrides locks set by the same process using a different
-** file descriptor.  Consider this test case:
-**
-**       int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
-**       int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
-**
-** Suppose ./file1 and ./file2 are really the same file (because
-** one is a hard or symbolic link to the other) then if you set
-** an exclusive lock on fd1, then try to get an exclusive lock
-** on fd2, it works.  I would have expected the second lock to
-** fail since there was already a lock on the file due to fd1.
-** But not so.  Since both locks came from the same process, the
-** second overrides the first, even though they were on different
-** file descriptors opened on different file names.
-**
-** This means that we cannot use POSIX locks to synchronize file access
-** among competing threads of the same process.  POSIX locks will work fine
-** to synchronize access for threads in separate processes, but not
-** threads within the same process.
-**
-** To work around the problem, SQLite has to manage file locks internally
-** on its own.  Whenever a new database is opened, we have to find the
-** specific inode of the database file (the inode is determined by the
-** st_dev and st_ino fields of the stat structure that fstat() fills in)
-** and check for locks already existing on that inode.  When locks are
-** created or removed, we have to look at our own internal record of the
-** locks to see if another thread has previously set a lock on that same
-** inode.
-**
-** (Aside: The use of inode numbers as unique IDs does not work on VxWorks.
-** For VxWorks, we have to use the alternative unique ID system based on
-** canonical filename and implemented in the previous division.)
-**
-** The sqlite3_file structure for POSIX is no longer just an integer file
-** descriptor.  It is now a structure that holds the integer file
-** descriptor and a pointer to a structure that describes the internal
-** locks on the corresponding inode.  There is one locking structure
-** per inode, so if the same inode is opened twice, both unixFile structures
-** point to the same locking structure.  The locking structure keeps
-** a reference count (so we will know when to delete it) and a "cnt"
-** field that tells us its internal lock status.  cnt==0 means the
-** file is unlocked.  cnt==-1 means the file has an exclusive lock.
-** cnt>0 means there are cnt shared locks on the file.
-**
-** Any attempt to lock or unlock a file first checks the locking
-** structure.  The fcntl() system call is only invoked to set a 
-** POSIX lock if the internal lock structure transitions between
-** a locked and an unlocked state.
-**
-** But wait:  there are yet more problems with POSIX advisory locks.
-**
-** If you close a file descriptor that points to a file that has locks,
-** all locks on that file that are owned by the current process are
-** released.  To work around this problem, each unixInodeInfo object
-** maintains a count of the number of pending locks on tha inode.
-** When an attempt is made to close an unixFile, if there are
-** other unixFile open on the same inode that are holding locks, the call
-** to close() the file descriptor is deferred until all of the locks clear.
-** The unixInodeInfo structure keeps a list of file descriptors that need to
-** be closed and that list is walked (and cleared) when the last lock
-** clears.
-**
-** Yet another problem:  LinuxThreads do not play well with posix locks.
-**
-** Many older versions of linux use the LinuxThreads library which is
-** not posix compliant.  Under LinuxThreads, a lock created by thread
-** A cannot be modified or overridden by a different thread B.
-** Only thread A can modify the lock.  Locking behavior is correct
-** if the appliation uses the newer Native Posix Thread Library (NPTL)
-** on linux - with NPTL a lock created by thread A can override locks
-** in thread B.  But there is no way to know at compile-time which
-** threading library is being used.  So there is no way to know at
-** compile-time whether or not thread A can override locks on thread B.
-** One has to do a run-time check to discover the behavior of the
-** current process.
-**
-** SQLite used to support LinuxThreads.  But support for LinuxThreads
-** was dropped beginning with version 3.7.0.  SQLite will still work with
-** LinuxThreads provided that (1) there is no more than one connection 
-** per database file in the same process and (2) database connections
-** do not move across threads.
-*/
-
-/*
-** An instance of the following structure serves as the key used
-** to locate a particular unixInodeInfo object.
-*/
-struct unixFileId {
-  dev_t dev;                  /* Device number */
-#if OS_VXWORKS
-  struct vxworksFileId *pId;  /* Unique file ID for vxworks. */
-#else
-  ino_t ino;                  /* Inode number */
-#endif
-};
-
-/*
-** An instance of the following structure is allocated for each open
-** inode.  Or, on LinuxThreads, there is one of these structures for
-** each inode opened by each thread.
-**
-** A single inode can have multiple file descriptors, so each unixFile
-** structure contains a pointer to an instance of this object and this
-** object keeps a count of the number of unixFile pointing to it.
-*/
-struct unixInodeInfo {
-  struct unixFileId fileId;       /* The lookup key */
-  int nShared;                    /* Number of SHARED locks held */
-  unsigned char eFileLock;        /* One of SHARED_LOCK, RESERVED_LOCK etc. */
-  unsigned char bProcessLock;     /* An exclusive process lock is held */
-  int nRef;                       /* Number of pointers to this structure */
-  unixShmNode *pShmNode;          /* Shared memory associated with this inode */
-  int nLock;                      /* Number of outstanding file locks */
-  UnixUnusedFd *pUnused;          /* Unused file descriptors to close */
-  unixInodeInfo *pNext;           /* List of all unixInodeInfo objects */
-  unixInodeInfo *pPrev;           /*    .... doubly linked */
-#if SQLITE_ENABLE_LOCKING_STYLE
-  unsigned long long sharedByte;  /* for AFP simulated shared lock */
-#endif
-#if OS_VXWORKS
-  sem_t *pSem;                    /* Named POSIX semaphore */
-  char aSemName[MAX_PATHNAME+2];  /* Name of that semaphore */
-#endif
-};
-
-/*
-** A lists of all unixInodeInfo objects.
-*/
-static unixInodeInfo *inodeList = 0;
-
-/*
-**
-** This function - unixLogError_x(), is only ever called via the macro
-** unixLogError().
-**
-** It is invoked after an error occurs in an OS function and errno has been
-** set. It logs a message using sqlite3_log() containing the current value of
-** errno and, if possible, the human-readable equivalent from strerror() or
-** strerror_r().
-**
-** The first argument passed to the macro should be the error code that
-** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN). 
-** The two subsequent arguments should be the name of the OS function that
-** failed (e.g. "unlink", "open") and the associated file-system path,
-** if any.
-*/
-#define unixLogError(a,b,c)     unixLogErrorAtLine(a,b,c,__LINE__)
-static int unixLogErrorAtLine(
-  int errcode,                    /* SQLite error code */
-  const char *zFunc,              /* Name of OS function that failed */
-  const char *zPath,              /* File path associated with error */
-  int iLine                       /* Source line number where error occurred */
-){
-  char *zErr;                     /* Message from strerror() or equivalent */
-  int iErrno = errno;             /* Saved syscall error number */
-
-  /* If this is not a threadsafe build (SQLITE_THREADSAFE==0), then use
-  ** the strerror() function to obtain the human-readable error message
-  ** equivalent to errno. Otherwise, use strerror_r().
-  */ 
-#if SQLITE_THREADSAFE && defined(HAVE_STRERROR_R)
-  char aErr[80];
-  memset(aErr, 0, sizeof(aErr));
-  zErr = aErr;
-
-  /* If STRERROR_R_CHAR_P (set by autoconf scripts) or __USE_GNU is defined,
-  ** assume that the system provides the GNU version of strerror_r() that
-  ** returns a pointer to a buffer containing the error message. That pointer 
-  ** may point to aErr[], or it may point to some static storage somewhere. 
-  ** Otherwise, assume that the system provides the POSIX version of 
-  ** strerror_r(), which always writes an error message into aErr[].
-  **
-  ** If the code incorrectly assumes that it is the POSIX version that is
-  ** available, the error message will often be an empty string. Not a
-  ** huge problem. Incorrectly concluding that the GNU version is available 
-  ** could lead to a segfault though.
-  */
-#if defined(STRERROR_R_CHAR_P) || defined(__USE_GNU)
-  zErr = 
-# endif
-  strerror_r(iErrno, aErr, sizeof(aErr)-1);
-
-#elif SQLITE_THREADSAFE
-  /* This is a threadsafe build, but strerror_r() is not available. */
-  zErr = "";
-#else
-  /* Non-threadsafe build, use strerror(). */
-  zErr = strerror(iErrno);
-#endif
-
-  if( zPath==0 ) zPath = "";
-  sqlite3_log(errcode,
-      "os_unix.c:%d: (%d) %s(%s) - %s",
-      iLine, iErrno, zFunc, zPath, zErr
-  );
-
-  return errcode;
-}
-
-/*
-** Close a file descriptor.
-**
-** We assume that close() almost always works, since it is only in a
-** very sick application or on a very sick platform that it might fail.
-** If it does fail, simply leak the file descriptor, but do log the
-** error.
-**
-** Note that it is not safe to retry close() after EINTR since the
-** file descriptor might have already been reused by another thread.
-** So we don't even try to recover from an EINTR.  Just log the error
-** and move on.
-*/
-static void robust_close(unixFile *pFile, int h, int lineno){
-  if( osClose(h) ){
-    unixLogErrorAtLine(SQLITE_IOERR_CLOSE, "close",
-                       pFile ? pFile->zPath : 0, lineno);
-  }
-}
-
-/*
-** Close all file descriptors accumuated in the unixInodeInfo->pUnused list.
-*/ 
-static void closePendingFds(unixFile *pFile){
-  unixInodeInfo *pInode = pFile->pInode;
-  UnixUnusedFd *p;
-  UnixUnusedFd *pNext;
-  for(p=pInode->pUnused; p; p=pNext){
-    pNext = p->pNext;
-    robust_close(pFile, p->fd, __LINE__);
-    sqlite3_free(p);
-  }
-  pInode->pUnused = 0;
-}
-
-/*
-** Release a unixInodeInfo structure previously allocated by findInodeInfo().
-**
-** The mutex entered using the unixEnterMutex() function must be held
-** when this function is called.
-*/
-static void releaseInodeInfo(unixFile *pFile){
-  unixInodeInfo *pInode = pFile->pInode;
-  assert( unixMutexHeld() );
-  if( ALWAYS(pInode) ){
-    pInode->nRef--;
-    if( pInode->nRef==0 ){
-      assert( pInode->pShmNode==0 );
-      closePendingFds(pFile);
-      if( pInode->pPrev ){
-        assert( pInode->pPrev->pNext==pInode );
-        pInode->pPrev->pNext = pInode->pNext;
-      }else{
-        assert( inodeList==pInode );
-        inodeList = pInode->pNext;
-      }
-      if( pInode->pNext ){
-        assert( pInode->pNext->pPrev==pInode );
-        pInode->pNext->pPrev = pInode->pPrev;
-      }
-      sqlite3_free(pInode);
-    }
-  }
-}
-
-/*
-** Given a file descriptor, locate the unixInodeInfo object that
-** describes that file descriptor.  Create a new one if necessary.  The
-** return value might be uninitialized if an error occurs.
-**
-** The mutex entered using the unixEnterMutex() function must be held
-** when this function is called.
-**
-** Return an appropriate error code.
-*/
-static int findInodeInfo(
-  unixFile *pFile,               /* Unix file with file desc used in the key */
-  unixInodeInfo **ppInode        /* Return the unixInodeInfo object here */
-){
-  int rc;                        /* System call return code */
-  int fd;                        /* The file descriptor for pFile */
-  struct unixFileId fileId;      /* Lookup key for the unixInodeInfo */
-  struct stat statbuf;           /* Low-level file information */
-  unixInodeInfo *pInode = 0;     /* Candidate unixInodeInfo object */
-
-  assert( unixMutexHeld() );
-
-  /* Get low-level information about the file that we can used to
-  ** create a unique name for the file.
-  */
-  fd = pFile->h;
-  rc = osFstat(fd, &statbuf);
-  if( rc!=0 ){
-    pFile->lastErrno = errno;
-#ifdef EOVERFLOW
-    if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
-#endif
-    return SQLITE_IOERR;
-  }
-
-#ifdef __APPLE__
-  /* On OS X on an msdos filesystem, the inode number is reported
-  ** incorrectly for zero-size files.  See ticket #3260.  To work
-  ** around this problem (we consider it a bug in OS X, not SQLite)
-  ** we always increase the file size to 1 by writing a single byte
-  ** prior to accessing the inode number.  The one byte written is
-  ** an ASCII 'S' character which also happens to be the first byte
-  ** in the header of every SQLite database.  In this way, if there
-  ** is a race condition such that another thread has already populated
-  ** the first page of the database, no damage is done.
-  */
-  if( statbuf.st_size==0 && (pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS)!=0 ){
-    do{ rc = osWrite(fd, "S", 1); }while( rc<0 && errno==EINTR );
-    if( rc!=1 ){
-      pFile->lastErrno = errno;
-      return SQLITE_IOERR;
-    }
-    rc = osFstat(fd, &statbuf);
-    if( rc!=0 ){
-      pFile->lastErrno = errno;
-      return SQLITE_IOERR;
-    }
-  }
-#endif
-
-  memset(&fileId, 0, sizeof(fileId));
-  fileId.dev = statbuf.st_dev;
-#if OS_VXWORKS
-  fileId.pId = pFile->pId;
-#else
-  fileId.ino = statbuf.st_ino;
-#endif
-  pInode = inodeList;
-  while( pInode && memcmp(&fileId, &pInode->fileId, sizeof(fileId)) ){
-    pInode = pInode->pNext;
-  }
-  if( pInode==0 ){
-    pInode = sqlite3_malloc( sizeof(*pInode) );
-    if( pInode==0 ){
-      return SQLITE_NOMEM;
-    }
-    memset(pInode, 0, sizeof(*pInode));
-    memcpy(&pInode->fileId, &fileId, sizeof(fileId));
-    pInode->nRef = 1;
-    pInode->pNext = inodeList;
-    pInode->pPrev = 0;
-    if( inodeList ) inodeList->pPrev = pInode;
-    inodeList = pInode;
-  }else{
-    pInode->nRef++;
-  }
-  *ppInode = pInode;
-  return SQLITE_OK;
-}
-
-
-/*
-** Check a unixFile that is a database.  Verify the following:
-**
-** (1) There is exactly one hard link on the file
-** (2) The file is not a symbolic link
-** (3) The file has not been renamed or unlinked
-**
-** Issue sqlite3_log(SQLITE_WARNING,...) messages if anything is not right.
-*/
-static void verifyDbFile(unixFile *pFile){
-  struct stat buf;
-  int rc;
-  if( pFile->ctrlFlags & UNIXFILE_WARNED ){
-    /* One or more of the following warnings have already been issued.  Do not
-    ** repeat them so as not to clutter the error log */
-    return;
-  }
-  rc = osFstat(pFile->h, &buf);
-  if( rc!=0 ){
-    sqlite3_log(SQLITE_WARNING, "cannot fstat db file %s", pFile->zPath);
-    pFile->ctrlFlags |= UNIXFILE_WARNED;
-    return;
-  }
-  if( buf.st_nlink==0 && (pFile->ctrlFlags & UNIXFILE_DELETE)==0 ){
-    sqlite3_log(SQLITE_WARNING, "file unlinked while open: %s", pFile->zPath);
-    pFile->ctrlFlags |= UNIXFILE_WARNED;
-    return;
-  }
-  if( buf.st_nlink>1 ){
-    sqlite3_log(SQLITE_WARNING, "multiple links to file: %s", pFile->zPath);
-    pFile->ctrlFlags |= UNIXFILE_WARNED;
-    return;
-  }
-  if( pFile->pInode!=0
-   && ((rc = osStat(pFile->zPath, &buf))!=0
-       || buf.st_ino!=pFile->pInode->fileId.ino)
-  ){
-    sqlite3_log(SQLITE_WARNING, "file renamed while open: %s", pFile->zPath);
-    pFile->ctrlFlags |= UNIXFILE_WARNED;
-    return;
-  }
-}
-
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-*/
-static int unixCheckReservedLock(sqlite3_file *id, int *pResOut){
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-
-  assert( pFile );
-  unixEnterMutex(); /* Because pFile->pInode is shared across threads */
-
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->pInode->eFileLock>SHARED_LOCK ){
-    reserved = 1;
-  }
-
-  /* Otherwise see if some other process holds it.
-  */
-#ifndef __DJGPP__
-  if( !reserved && !pFile->pInode->bProcessLock ){
-    struct flock lock;
-    lock.l_whence = SEEK_SET;
-    lock.l_start = RESERVED_BYTE;
-    lock.l_len = 1;
-    lock.l_type = F_WRLCK;
-    if( osFcntl(pFile->h, F_GETLK, &lock) ){
-      rc = SQLITE_IOERR_CHECKRESERVEDLOCK;
-      pFile->lastErrno = errno;
-    } else if( lock.l_type!=F_UNLCK ){
-      reserved = 1;
-    }
-  }
-#endif
-  
-  unixLeaveMutex();
-  OSTRACE(("TEST WR-LOCK %d %d %d (unix)\n", pFile->h, rc, reserved));
-
-  *pResOut = reserved;
-  return rc;
-}
-
-/*
-** Attempt to set a system-lock on the file pFile.  The lock is 
-** described by pLock.
-**
-** If the pFile was opened read/write from unix-excl, then the only lock
-** ever obtained is an exclusive lock, and it is obtained exactly once
-** the first time any lock is attempted.  All subsequent system locking
-** operations become no-ops.  Locking operations still happen internally,
-** in order to coordinate access between separate database connections
-** within this process, but all of that is handled in memory and the
-** operating system does not participate.
-**
-** This function is a pass-through to fcntl(F_SETLK) if pFile is using
-** any VFS other than "unix-excl" or if pFile is opened on "unix-excl"
-** and is read-only.
-**
-** Zero is returned if the call completes successfully, or -1 if a call
-** to fcntl() fails. In this case, errno is set appropriately (by fcntl()).
-*/
-static int unixFileLock(unixFile *pFile, struct flock *pLock){
-  int rc;
-  unixInodeInfo *pInode = pFile->pInode;
-  assert( unixMutexHeld() );
-  assert( pInode!=0 );
-  if( ((pFile->ctrlFlags & UNIXFILE_EXCL)!=0 || pInode->bProcessLock)
-   && ((pFile->ctrlFlags & UNIXFILE_RDONLY)==0)
-  ){
-    if( pInode->bProcessLock==0 ){
-      struct flock lock;
-      assert( pInode->nLock==0 );
-      lock.l_whence = SEEK_SET;
-      lock.l_start = SHARED_FIRST;
-      lock.l_len = SHARED_SIZE;
-      lock.l_type = F_WRLCK;
-      rc = osFcntl(pFile->h, F_SETLK, &lock);
-      if( rc<0 ) return rc;
-      pInode->bProcessLock = 1;
-      pInode->nLock++;
-    }else{
-      rc = 0;
-    }
-  }else{
-    rc = osFcntl(pFile->h, F_SETLK, pLock);
-  }
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-*/
-static int unixLock(sqlite3_file *id, int eFileLock){
-  /* The following describes the implementation of the various locks and
-  ** lock transitions in terms of the POSIX advisory shared and exclusive
-  ** lock primitives (called read-locks and write-locks below, to avoid
-  ** confusion with SQLite lock names). The algorithms are complicated
-  ** slightly in order to be compatible with windows systems simultaneously
-  ** accessing the same database file, in case that is ever required.
-  **
-  ** Symbols defined in os.h indentify the 'pending byte' and the 'reserved
-  ** byte', each single bytes at well known offsets, and the 'shared byte
-  ** range', a range of 510 bytes at a well known offset.
-  **
-  ** To obtain a SHARED lock, a read-lock is obtained on the 'pending
-  ** byte'.  If this is successful, a random byte from the 'shared byte
-  ** range' is read-locked and the lock on the 'pending byte' released.
-  **
-  ** A process may only obtain a RESERVED lock after it has a SHARED lock.
-  ** A RESERVED lock is implemented by grabbing a write-lock on the
-  ** 'reserved byte'. 
-  **
-  ** A process may only obtain a PENDING lock after it has obtained a
-  ** SHARED lock. A PENDING lock is implemented by obtaining a write-lock
-  ** on the 'pending byte'. This ensures that no new SHARED locks can be
-  ** obtained, but existing SHARED locks are allowed to persist. A process
-  ** does not have to obtain a RESERVED lock on the way to a PENDING lock.
-  ** This property is used by the algorithm for rolling back a journal file
-  ** after a crash.
-  **
-  ** An EXCLUSIVE lock, obtained after a PENDING lock is held, is
-  ** implemented by obtaining a write-lock on the entire 'shared byte
-  ** range'. Since all other locks require a read-lock on one of the bytes
-  ** within this range, this ensures that no other locks are held on the
-  ** database. 
-  **
-  ** The reason a single byte cannot be used instead of the 'shared byte
-  ** range' is that some versions of windows do not support read-locks. By
-  ** locking a random byte from a range, concurrent SHARED locks may exist
-  ** even if the locking primitive used is always a write-lock.
-  */
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile*)id;
-  unixInodeInfo *pInode;
-  struct flock lock;
-  int tErrno = 0;
-
-  assert( pFile );
-  OSTRACE(("LOCK    %d %s was %s(%s,%d) pid=%d (unix)\n", pFile->h,
-      azFileLock(eFileLock), azFileLock(pFile->eFileLock),
-      azFileLock(pFile->pInode->eFileLock), pFile->pInode->nShared , getpid()));
-
-  /* If there is already a lock of this type or more restrictive on the
-  ** unixFile, do nothing. Don't use the end_lock: exit path, as
-  ** unixEnterMutex() hasn't been called yet.
-  */
-  if( pFile->eFileLock>=eFileLock ){
-    OSTRACE(("LOCK    %d %s ok (already held) (unix)\n", pFile->h,
-            azFileLock(eFileLock)));
-    return SQLITE_OK;
-  }
-
-  /* Make sure the locking sequence is correct.
-  **  (1) We never move from unlocked to anything higher than shared lock.
-  **  (2) SQLite never explicitly requests a pendig lock.
-  **  (3) A shared lock is always held when a reserve lock is requested.
-  */
-  assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
-  assert( eFileLock!=PENDING_LOCK );
-  assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
-
-  /* This mutex is needed because pFile->pInode is shared across threads
-  */
-  unixEnterMutex();
-  pInode = pFile->pInode;
-
-  /* If some thread using this PID has a lock via a different unixFile*
-  ** handle that precludes the requested lock, return BUSY.
-  */
-  if( (pFile->eFileLock!=pInode->eFileLock && 
-          (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
-  ){
-    rc = SQLITE_BUSY;
-    goto end_lock;
-  }
-
-  /* If a SHARED lock is requested, and some thread using this PID already
-  ** has a SHARED or RESERVED lock, then increment reference counts and
-  ** return SQLITE_OK.
-  */
-  if( eFileLock==SHARED_LOCK && 
-      (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
-    assert( eFileLock==SHARED_LOCK );
-    assert( pFile->eFileLock==0 );
-    assert( pInode->nShared>0 );
-    pFile->eFileLock = SHARED_LOCK;
-    pInode->nShared++;
-    pInode->nLock++;
-    goto end_lock;
-  }
-
-
-  /* A PENDING lock is needed before acquiring a SHARED lock and before
-  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
-  ** be released.
-  */
-  lock.l_len = 1L;
-  lock.l_whence = SEEK_SET;
-  if( eFileLock==SHARED_LOCK 
-      || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLock<PENDING_LOCK)
-  ){
-    lock.l_type = (eFileLock==SHARED_LOCK?F_RDLCK:F_WRLCK);
-    lock.l_start = PENDING_BYTE;
-    if( unixFileLock(pFile, &lock) ){
-      tErrno = errno;
-      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
-      if( rc!=SQLITE_BUSY ){
-        pFile->lastErrno = tErrno;
-      }
-      goto end_lock;
-    }
-  }
-
-
-  /* If control gets to this point, then actually go ahead and make
-  ** operating system calls for the specified lock.
-  */
-  if( eFileLock==SHARED_LOCK ){
-    assert( pInode->nShared==0 );
-    assert( pInode->eFileLock==0 );
-    assert( rc==SQLITE_OK );
-
-    /* Now get the read-lock */
-    lock.l_start = SHARED_FIRST;
-    lock.l_len = SHARED_SIZE;
-    if( unixFileLock(pFile, &lock) ){
-      tErrno = errno;
-      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
-    }
-
-    /* Drop the temporary PENDING lock */
-    lock.l_start = PENDING_BYTE;
-    lock.l_len = 1L;
-    lock.l_type = F_UNLCK;
-    if( unixFileLock(pFile, &lock) && rc==SQLITE_OK ){
-      /* This could happen with a network mount */
-      tErrno = errno;
-      rc = SQLITE_IOERR_UNLOCK; 
-    }
-
-    if( rc ){
-      if( rc!=SQLITE_BUSY ){
-        pFile->lastErrno = tErrno;
-      }
-      goto end_lock;
-    }else{
-      pFile->eFileLock = SHARED_LOCK;
-      pInode->nLock++;
-      pInode->nShared = 1;
-    }
-  }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
-    /* We are trying for an exclusive lock but another thread in this
-    ** same process is still holding a shared lock. */
-    rc = SQLITE_BUSY;
-  }else{
-    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
-    ** assumed that there is a SHARED or greater lock on the file
-    ** already.
-    */
-    assert( 0!=pFile->eFileLock );
-    lock.l_type = F_WRLCK;
-
-    assert( eFileLock==RESERVED_LOCK || eFileLock==EXCLUSIVE_LOCK );
-    if( eFileLock==RESERVED_LOCK ){
-      lock.l_start = RESERVED_BYTE;
-      lock.l_len = 1L;
-    }else{
-      lock.l_start = SHARED_FIRST;
-      lock.l_len = SHARED_SIZE;
-    }
-
-    if( unixFileLock(pFile, &lock) ){
-      tErrno = errno;
-      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
-      if( rc!=SQLITE_BUSY ){
-        pFile->lastErrno = tErrno;
-      }
-    }
-  }
-  
-
-#ifdef SQLITE_DEBUG
-  /* Set up the transaction-counter change checking flags when
-  ** transitioning from a SHARED to a RESERVED lock.  The change
-  ** from SHARED to RESERVED marks the beginning of a normal
-  ** write operation (not a hot journal rollback).
-  */
-  if( rc==SQLITE_OK
-   && pFile->eFileLock<=SHARED_LOCK
-   && eFileLock==RESERVED_LOCK
-  ){
-    pFile->transCntrChng = 0;
-    pFile->dbUpdate = 0;
-    pFile->inNormalWrite = 1;
-  }
-#endif
-
-
-  if( rc==SQLITE_OK ){
-    pFile->eFileLock = eFileLock;
-    pInode->eFileLock = eFileLock;
-  }else if( eFileLock==EXCLUSIVE_LOCK ){
-    pFile->eFileLock = PENDING_LOCK;
-    pInode->eFileLock = PENDING_LOCK;
-  }
-
-end_lock:
-  unixLeaveMutex();
-  OSTRACE(("LOCK    %d %s %s (unix)\n", pFile->h, azFileLock(eFileLock), 
-      rc==SQLITE_OK ? "ok" : "failed"));
-  return rc;
-}
-
-/*
-** Add the file descriptor used by file handle pFile to the corresponding
-** pUnused list.
-*/
-static void setPendingFd(unixFile *pFile){
-  unixInodeInfo *pInode = pFile->pInode;
-  UnixUnusedFd *p = pFile->pUnused;
-  p->pNext = pInode->pUnused;
-  pInode->pUnused = p;
-  pFile->h = -1;
-  pFile->pUnused = 0;
-}
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-** 
-** If handleNFSUnlock is true, then on downgrading an EXCLUSIVE_LOCK to SHARED
-** the byte range is divided into 2 parts and the first part is unlocked then
-** set to a read lock, then the other part is simply unlocked.  This works 
-** around a bug in BSD NFS lockd (also seen on MacOSX 10.3+) that fails to 
-** remove the write lock on a region when a read lock is set.
-*/
-static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
-  unixFile *pFile = (unixFile*)id;
-  unixInodeInfo *pInode;
-  struct flock lock;
-  int rc = SQLITE_OK;
-
-  assert( pFile );
-  OSTRACE(("UNLOCK  %d %d was %d(%d,%d) pid=%d (unix)\n", pFile->h, eFileLock,
-      pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
-      getpid()));
-
-  assert( eFileLock<=SHARED_LOCK );
-  if( pFile->eFileLock<=eFileLock ){
-    return SQLITE_OK;
-  }
-  unixEnterMutex();
-  pInode = pFile->pInode;
-  assert( pInode->nShared!=0 );
-  if( pFile->eFileLock>SHARED_LOCK ){
-    assert( pInode->eFileLock==pFile->eFileLock );
-
-#ifdef SQLITE_DEBUG
-    /* When reducing a lock such that other processes can start
-    ** reading the database file again, make sure that the
-    ** transaction counter was updated if any part of the database
-    ** file changed.  If the transaction counter is not updated,
-    ** other connections to the same file might not realize that
-    ** the file has changed and hence might not know to flush their
-    ** cache.  The use of a stale cache can lead to database corruption.
-    */
-    pFile->inNormalWrite = 0;
-#endif
-
-    /* downgrading to a shared lock on NFS involves clearing the write lock
-    ** before establishing the readlock - to avoid a race condition we downgrade
-    ** the lock in 2 blocks, so that part of the range will be covered by a 
-    ** write lock until the rest is covered by a read lock:
-    **  1:   [WWWWW]
-    **  2:   [....W]
-    **  3:   [RRRRW]
-    **  4:   [RRRR.]
-    */
-    if( eFileLock==SHARED_LOCK ){
-
-#if !defined(__APPLE__) || !SQLITE_ENABLE_LOCKING_STYLE
-      (void)handleNFSUnlock;
-      assert( handleNFSUnlock==0 );
-#endif
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-      if( handleNFSUnlock ){
-        int tErrno;               /* Error code from system call errors */
-        off_t divSize = SHARED_SIZE - 1;
-        
-        lock.l_type = F_UNLCK;
-        lock.l_whence = SEEK_SET;
-        lock.l_start = SHARED_FIRST;
-        lock.l_len = divSize;
-        if( unixFileLock(pFile, &lock)==(-1) ){
-          tErrno = errno;
-          rc = SQLITE_IOERR_UNLOCK;
-          if( IS_LOCK_ERROR(rc) ){
-            pFile->lastErrno = tErrno;
-          }
-          goto end_unlock;
-        }
-        lock.l_type = F_RDLCK;
-        lock.l_whence = SEEK_SET;
-        lock.l_start = SHARED_FIRST;
-        lock.l_len = divSize;
-        if( unixFileLock(pFile, &lock)==(-1) ){
-          tErrno = errno;
-          rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
-          if( IS_LOCK_ERROR(rc) ){
-            pFile->lastErrno = tErrno;
-          }
-          goto end_unlock;
-        }
-        lock.l_type = F_UNLCK;
-        lock.l_whence = SEEK_SET;
-        lock.l_start = SHARED_FIRST+divSize;
-        lock.l_len = SHARED_SIZE-divSize;
-        if( unixFileLock(pFile, &lock)==(-1) ){
-          tErrno = errno;
-          rc = SQLITE_IOERR_UNLOCK;
-          if( IS_LOCK_ERROR(rc) ){
-            pFile->lastErrno = tErrno;
-          }
-          goto end_unlock;
-        }
-      }else
-#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
-      {
-        lock.l_type = F_RDLCK;
-        lock.l_whence = SEEK_SET;
-        lock.l_start = SHARED_FIRST;
-        lock.l_len = SHARED_SIZE;
-        if( unixFileLock(pFile, &lock) ){
-          /* In theory, the call to unixFileLock() cannot fail because another
-          ** process is holding an incompatible lock. If it does, this 
-          ** indicates that the other process is not following the locking
-          ** protocol. If this happens, return SQLITE_IOERR_RDLOCK. Returning
-          ** SQLITE_BUSY would confuse the upper layer (in practice it causes 
-          ** an assert to fail). */ 
-          rc = SQLITE_IOERR_RDLOCK;
-          pFile->lastErrno = errno;
-          goto end_unlock;
-        }
-      }
-    }
-    lock.l_type = F_UNLCK;
-    lock.l_whence = SEEK_SET;
-    lock.l_start = PENDING_BYTE;
-    lock.l_len = 2L;  assert( PENDING_BYTE+1==RESERVED_BYTE );
-    if( unixFileLock(pFile, &lock)==0 ){
-      pInode->eFileLock = SHARED_LOCK;
-    }else{
-      rc = SQLITE_IOERR_UNLOCK;
-      pFile->lastErrno = errno;
-      goto end_unlock;
-    }
-  }
-  if( eFileLock==NO_LOCK ){
-    /* Decrement the shared lock counter.  Release the lock using an
-    ** OS call only when all threads in this same process have released
-    ** the lock.
-    */
-    pInode->nShared--;
-    if( pInode->nShared==0 ){
-      lock.l_type = F_UNLCK;
-      lock.l_whence = SEEK_SET;
-      lock.l_start = lock.l_len = 0L;
-      if( unixFileLock(pFile, &lock)==0 ){
-        pInode->eFileLock = NO_LOCK;
-      }else{
-        rc = SQLITE_IOERR_UNLOCK;
-        pFile->lastErrno = errno;
-        pInode->eFileLock = NO_LOCK;
-        pFile->eFileLock = NO_LOCK;
-      }
-    }
-
-    /* Decrement the count of locks against this same file.  When the
-    ** count reaches zero, close any other file descriptors whose close
-    ** was deferred because of outstanding locks.
-    */
-    pInode->nLock--;
-    assert( pInode->nLock>=0 );
-    if( pInode->nLock==0 ){
-      closePendingFds(pFile);
-    }
-  }
-
-end_unlock:
-  unixLeaveMutex();
-  if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
-  return rc;
-}
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-*/
-static int unixUnlock(sqlite3_file *id, int eFileLock){
-  assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
-  return posixUnlock(id, eFileLock, 0);
-}
-
-#if SQLITE_MAX_MMAP_SIZE>0
-static int unixMapfile(unixFile *pFd, i64 nByte);
-static void unixUnmapfile(unixFile *pFd);
-#endif
-
-/*
-** This function performs the parts of the "close file" operation 
-** common to all locking schemes. It closes the directory and file
-** handles, if they are valid, and sets all fields of the unixFile
-** structure to 0.
-**
-** It is *not* necessary to hold the mutex when this routine is called,
-** even on VxWorks.  A mutex will be acquired on VxWorks by the
-** vxworksReleaseFileId() routine.
-*/
-static int closeUnixFile(sqlite3_file *id){
-  unixFile *pFile = (unixFile*)id;
-#if SQLITE_MAX_MMAP_SIZE>0
-  unixUnmapfile(pFile);
-#endif
-  if( pFile->h>=0 ){
-    robust_close(pFile, pFile->h, __LINE__);
-    pFile->h = -1;
-  }
-#if OS_VXWORKS
-  if( pFile->pId ){
-    if( pFile->ctrlFlags & UNIXFILE_DELETE ){
-      osUnlink(pFile->pId->zCanonicalName);
-    }
-    vxworksReleaseFileId(pFile->pId);
-    pFile->pId = 0;
-  }
-#endif
-  OSTRACE(("CLOSE   %-3d\n", pFile->h));
-  OpenCounter(-1);
-  sqlite3_free(pFile->pUnused);
-  memset(pFile, 0, sizeof(unixFile));
-  return SQLITE_OK;
-}
-
-/*
-** Close a file.
-*/
-static int unixClose(sqlite3_file *id){
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile *)id;
-  verifyDbFile(pFile);
-  unixUnlock(id, NO_LOCK);
-  unixEnterMutex();
-
-  /* unixFile.pInode is always valid here. Otherwise, a different close
-  ** routine (e.g. nolockClose()) would be called instead.
-  */
-  assert( pFile->pInode->nLock>0 || pFile->pInode->bProcessLock==0 );
-  if( ALWAYS(pFile->pInode) && pFile->pInode->nLock ){
-    /* If there are outstanding locks, do not actually close the file just
-    ** yet because that would clear those locks.  Instead, add the file
-    ** descriptor to pInode->pUnused list.  It will be automatically closed 
-    ** when the last lock is cleared.
-    */
-    setPendingFd(pFile);
-  }
-  releaseInodeInfo(pFile);
-  rc = closeUnixFile(id);
-  unixLeaveMutex();
-  return rc;
-}
-
-/************** End of the posix advisory lock implementation *****************
-******************************************************************************/
-
-/******************************************************************************
-****************************** No-op Locking **********************************
-**
-** Of the various locking implementations available, this is by far the
-** simplest:  locking is ignored.  No attempt is made to lock the database
-** file for reading or writing.
-**
-** This locking mode is appropriate for use on read-only databases
-** (ex: databases that are burned into CD-ROM, for example.)  It can
-** also be used if the application employs some external mechanism to
-** prevent simultaneous access of the same database by two or more
-** database connections.  But there is a serious risk of database
-** corruption if this locking mode is used in situations where multiple
-** database connections are accessing the same database file at the same
-** time and one or more of those connections are writing.
-*/
-
-static int nolockCheckReservedLock(sqlite3_file *NotUsed, int *pResOut){
-  UNUSED_PARAMETER(NotUsed);
-  *pResOut = 0;
-  return SQLITE_OK;
-}
-static int nolockLock(sqlite3_file *NotUsed, int NotUsed2){
-  UNUSED_PARAMETER2(NotUsed, NotUsed2);
-  return SQLITE_OK;
-}
-static int nolockUnlock(sqlite3_file *NotUsed, int NotUsed2){
-  UNUSED_PARAMETER2(NotUsed, NotUsed2);
-  return SQLITE_OK;
-}
-
-/*
-** Close the file.
-*/
-static int nolockClose(sqlite3_file *id) {
-  return closeUnixFile(id);
-}
-
-/******************* End of the no-op lock implementation *********************
-******************************************************************************/
-
-/******************************************************************************
-************************* Begin dot-file Locking ******************************
-**
-** The dotfile locking implementation uses the existence of separate lock
-** files (really a directory) to control access to the database.  This works
-** on just about every filesystem imaginable.  But there are serious downsides:
-**
-**    (1)  There is zero concurrency.  A single reader blocks all other
-**         connections from reading or writing the database.
-**
-**    (2)  An application crash or power loss can leave stale lock files
-**         sitting around that need to be cleared manually.
-**
-** Nevertheless, a dotlock is an appropriate locking mode for use if no
-** other locking strategy is available.
-**
-** Dotfile locking works by creating a subdirectory in the same directory as
-** the database and with the same name but with a ".lock" extension added.
-** The existence of a lock directory implies an EXCLUSIVE lock.  All other
-** lock types (SHARED, RESERVED, PENDING) are mapped into EXCLUSIVE.
-*/
-
-/*
-** The file suffix added to the data base filename in order to create the
-** lock directory.
-*/
-#define DOTLOCK_SUFFIX ".lock"
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-**
-** In dotfile locking, either a lock exists or it does not.  So in this
-** variation of CheckReservedLock(), *pResOut is set to true if any lock
-** is held on the file and false if the file is unlocked.
-*/
-static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-  
-  assert( pFile );
-
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->eFileLock>SHARED_LOCK ){
-    /* Either this connection or some other connection in the same process
-    ** holds a lock on the file.  No need to check further. */
-    reserved = 1;
-  }else{
-    /* The lock is held if and only if the lockfile exists */
-    const char *zLockFile = (const char*)pFile->lockingContext;
-    reserved = osAccess(zLockFile, 0)==0;
-  }
-  OSTRACE(("TEST WR-LOCK %d %d %d (dotlock)\n", pFile->h, rc, reserved));
-  *pResOut = reserved;
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-**
-** With dotfile locking, we really only support state (4): EXCLUSIVE.
-** But we track the other locking levels internally.
-*/
-static int dotlockLock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  char *zLockFile = (char *)pFile->lockingContext;
-  int rc = SQLITE_OK;
-
-
-  /* If we have any lock, then the lock file already exists.  All we have
-  ** to do is adjust our internal record of the lock level.
-  */
-  if( pFile->eFileLock > NO_LOCK ){
-    pFile->eFileLock = eFileLock;
-    /* Always update the timestamp on the old file */
-#ifdef HAVE_UTIME
-    utime(zLockFile, NULL);
-#else
-    utimes(zLockFile, NULL);
-#endif
-    return SQLITE_OK;
-  }
-  
-  /* grab an exclusive lock */
-  rc = osMkdir(zLockFile, 0777);
-  if( rc<0 ){
-    /* failed to open/create the lock directory */
-    int tErrno = errno;
-    if( EEXIST == tErrno ){
-      rc = SQLITE_BUSY;
-    } else {
-      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
-      if( IS_LOCK_ERROR(rc) ){
-        pFile->lastErrno = tErrno;
-      }
-    }
-    return rc;
-  } 
-  
-  /* got it, set the type and return ok */
-  pFile->eFileLock = eFileLock;
-  return rc;
-}
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-**
-** When the locking level reaches NO_LOCK, delete the lock file.
-*/
-static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  char *zLockFile = (char *)pFile->lockingContext;
-  int rc;
-
-  assert( pFile );
-  OSTRACE(("UNLOCK  %d %d was %d pid=%d (dotlock)\n", pFile->h, eFileLock,
-           pFile->eFileLock, getpid()));
-  assert( eFileLock<=SHARED_LOCK );
-  
-  /* no-op if possible */
-  if( pFile->eFileLock==eFileLock ){
-    return SQLITE_OK;
-  }
-
-  /* To downgrade to shared, simply update our internal notion of the
-  ** lock state.  No need to mess with the file on disk.
-  */
-  if( eFileLock==SHARED_LOCK ){
-    pFile->eFileLock = SHARED_LOCK;
-    return SQLITE_OK;
-  }
-  
-  /* To fully unlock the database, delete the lock file */
-  assert( eFileLock==NO_LOCK );
-  rc = osRmdir(zLockFile);
-  if( rc<0 && errno==ENOTDIR ) rc = osUnlink(zLockFile);
-  if( rc<0 ){
-    int tErrno = errno;
-    rc = 0;
-    if( ENOENT != tErrno ){
-      rc = SQLITE_IOERR_UNLOCK;
-    }
-    if( IS_LOCK_ERROR(rc) ){
-      pFile->lastErrno = tErrno;
-    }
-    return rc; 
-  }
-  pFile->eFileLock = NO_LOCK;
-  return SQLITE_OK;
-}
-
-/*
-** Close a file.  Make sure the lock has been released before closing.
-*/
-static int dotlockClose(sqlite3_file *id) {
-  int rc = SQLITE_OK;
-  if( id ){
-    unixFile *pFile = (unixFile*)id;
-    dotlockUnlock(id, NO_LOCK);
-    sqlite3_free(pFile->lockingContext);
-    rc = closeUnixFile(id);
-  }
-  return rc;
-}
-/****************** End of the dot-file lock implementation *******************
-******************************************************************************/
-
-/******************************************************************************
-************************** Begin flock Locking ********************************
-**
-** Use the flock() system call to do file locking.
-**
-** flock() locking is like dot-file locking in that the various
-** fine-grain locking levels supported by SQLite are collapsed into
-** a single exclusive lock.  In other words, SHARED, RESERVED, and
-** PENDING locks are the same thing as an EXCLUSIVE lock.  SQLite
-** still works when you do this, but concurrency is reduced since
-** only a single process can be reading the database at a time.
-**
-** Omit this section if SQLITE_ENABLE_LOCKING_STYLE is turned off or if
-** compiling for VXWORKS.
-*/
-#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
-
-/*
-** Retry flock() calls that fail with EINTR
-*/
-#ifdef EINTR
-static int robust_flock(int fd, int op){
-  int rc;
-  do{ rc = flock(fd,op); }while( rc<0 && errno==EINTR );
-  return rc;
-}
-#else
-# define robust_flock(a,b) flock(a,b)
-#endif
-     
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-*/
-static int flockCheckReservedLock(sqlite3_file *id, int *pResOut){
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-  
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-  
-  assert( pFile );
-  
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->eFileLock>SHARED_LOCK ){
-    reserved = 1;
-  }
-  
-  /* Otherwise see if some other process holds it. */
-  if( !reserved ){
-    /* attempt to get the lock */
-    int lrc = robust_flock(pFile->h, LOCK_EX | LOCK_NB);
-    if( !lrc ){
-      /* got the lock, unlock it */
-      lrc = robust_flock(pFile->h, LOCK_UN);
-      if ( lrc ) {
-        int tErrno = errno;
-        /* unlock failed with an error */
-        lrc = SQLITE_IOERR_UNLOCK; 
-        if( IS_LOCK_ERROR(lrc) ){
-          pFile->lastErrno = tErrno;
-          rc = lrc;
-        }
-      }
-    } else {
-      int tErrno = errno;
-      reserved = 1;
-      /* someone else might have it reserved */
-      lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK); 
-      if( IS_LOCK_ERROR(lrc) ){
-        pFile->lastErrno = tErrno;
-        rc = lrc;
-      }
-    }
-  }
-  OSTRACE(("TEST WR-LOCK %d %d %d (flock)\n", pFile->h, rc, reserved));
-
-#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
-  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
-    rc = SQLITE_OK;
-    reserved=1;
-  }
-#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
-  *pResOut = reserved;
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** flock() only really support EXCLUSIVE locks.  We track intermediate
-** lock states in the sqlite3_file structure, but all locks SHARED or
-** above are really EXCLUSIVE locks and exclude all other processes from
-** access the file.
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-*/
-static int flockLock(sqlite3_file *id, int eFileLock) {
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile*)id;
-
-  assert( pFile );
-
-  /* if we already have a lock, it is exclusive.  
-  ** Just adjust level and punt on outta here. */
-  if (pFile->eFileLock > NO_LOCK) {
-    pFile->eFileLock = eFileLock;
-    return SQLITE_OK;
-  }
-  
-  /* grab an exclusive lock */
-  
-  if (robust_flock(pFile->h, LOCK_EX | LOCK_NB)) {
-    int tErrno = errno;
-    /* didn't get, must be busy */
-    rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
-    if( IS_LOCK_ERROR(rc) ){
-      pFile->lastErrno = tErrno;
-    }
-  } else {
-    /* got it, set the type and return ok */
-    pFile->eFileLock = eFileLock;
-  }
-  OSTRACE(("LOCK    %d %s %s (flock)\n", pFile->h, azFileLock(eFileLock), 
-           rc==SQLITE_OK ? "ok" : "failed"));
-#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
-  if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
-    rc = SQLITE_BUSY;
-  }
-#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
-  return rc;
-}
-
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-*/
-static int flockUnlock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  
-  assert( pFile );
-  OSTRACE(("UNLOCK  %d %d was %d pid=%d (flock)\n", pFile->h, eFileLock,
-           pFile->eFileLock, getpid()));
-  assert( eFileLock<=SHARED_LOCK );
-  
-  /* no-op if possible */
-  if( pFile->eFileLock==eFileLock ){
-    return SQLITE_OK;
-  }
-  
-  /* shared can just be set because we always have an exclusive */
-  if (eFileLock==SHARED_LOCK) {
-    pFile->eFileLock = eFileLock;
-    return SQLITE_OK;
-  }
-  
-  /* no, really, unlock. */
-  if( robust_flock(pFile->h, LOCK_UN) ){
-#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
-    return SQLITE_OK;
-#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
-    return SQLITE_IOERR_UNLOCK;
-  }else{
-    pFile->eFileLock = NO_LOCK;
-    return SQLITE_OK;
-  }
-}
-
-/*
-** Close a file.
-*/
-static int flockClose(sqlite3_file *id) {
-  int rc = SQLITE_OK;
-  if( id ){
-    flockUnlock(id, NO_LOCK);
-    rc = closeUnixFile(id);
-  }
-  return rc;
-}
-
-#endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */
-
-/******************* End of the flock lock implementation *********************
-******************************************************************************/
-
-/******************************************************************************
-************************ Begin Named Semaphore Locking ************************
-**
-** Named semaphore locking is only supported on VxWorks.
-**
-** Semaphore locking is like dot-lock and flock in that it really only
-** supports EXCLUSIVE locking.  Only a single process can read or write
-** the database file at a time.  This reduces potential concurrency, but
-** makes the lock implementation much easier.
-*/
-#if OS_VXWORKS
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-*/
-static int semCheckReservedLock(sqlite3_file *id, int *pResOut) {
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-  
-  assert( pFile );
-
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->eFileLock>SHARED_LOCK ){
-    reserved = 1;
-  }
-  
-  /* Otherwise see if some other process holds it. */
-  if( !reserved ){
-    sem_t *pSem = pFile->pInode->pSem;
-    struct stat statBuf;
-
-    if( sem_trywait(pSem)==-1 ){
-      int tErrno = errno;
-      if( EAGAIN != tErrno ){
-        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
-        pFile->lastErrno = tErrno;
-      } else {
-        /* someone else has the lock when we are in NO_LOCK */
-        reserved = (pFile->eFileLock < SHARED_LOCK);
-      }
-    }else{
-      /* we could have it if we want it */
-      sem_post(pSem);
-    }
-  }
-  OSTRACE(("TEST WR-LOCK %d %d %d (sem)\n", pFile->h, rc, reserved));
-
-  *pResOut = reserved;
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** Semaphore locks only really support EXCLUSIVE locks.  We track intermediate
-** lock states in the sqlite3_file structure, but all locks SHARED or
-** above are really EXCLUSIVE locks and exclude all other processes from
-** access the file.
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-*/
-static int semLock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  int fd;
-  sem_t *pSem = pFile->pInode->pSem;
-  int rc = SQLITE_OK;
-
-  /* if we already have a lock, it is exclusive.  
-  ** Just adjust level and punt on outta here. */
-  if (pFile->eFileLock > NO_LOCK) {
-    pFile->eFileLock = eFileLock;
-    rc = SQLITE_OK;
-    goto sem_end_lock;
-  }
-  
-  /* lock semaphore now but bail out when already locked. */
-  if( sem_trywait(pSem)==-1 ){
-    rc = SQLITE_BUSY;
-    goto sem_end_lock;
-  }
-
-  /* got it, set the type and return ok */
-  pFile->eFileLock = eFileLock;
-
- sem_end_lock:
-  return rc;
-}
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-*/
-static int semUnlock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  sem_t *pSem = pFile->pInode->pSem;
-
-  assert( pFile );
-  assert( pSem );
-  OSTRACE(("UNLOCK  %d %d was %d pid=%d (sem)\n", pFile->h, eFileLock,
-           pFile->eFileLock, getpid()));
-  assert( eFileLock<=SHARED_LOCK );
-  
-  /* no-op if possible */
-  if( pFile->eFileLock==eFileLock ){
-    return SQLITE_OK;
-  }
-  
-  /* shared can just be set because we always have an exclusive */
-  if (eFileLock==SHARED_LOCK) {
-    pFile->eFileLock = eFileLock;
-    return SQLITE_OK;
-  }
-  
-  /* no, really unlock. */
-  if ( sem_post(pSem)==-1 ) {
-    int rc, tErrno = errno;
-    rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
-    if( IS_LOCK_ERROR(rc) ){
-      pFile->lastErrno = tErrno;
-    }
-    return rc; 
-  }
-  pFile->eFileLock = NO_LOCK;
-  return SQLITE_OK;
-}
-
-/*
- ** Close a file.
- */
-static int semClose(sqlite3_file *id) {
-  if( id ){
-    unixFile *pFile = (unixFile*)id;
-    semUnlock(id, NO_LOCK);
-    assert( pFile );
-    unixEnterMutex();
-    releaseInodeInfo(pFile);
-    unixLeaveMutex();
-    closeUnixFile(id);
-  }
-  return SQLITE_OK;
-}
-
-#endif /* OS_VXWORKS */
-/*
-** Named semaphore locking is only available on VxWorks.
-**
-*************** End of the named semaphore lock implementation ****************
-******************************************************************************/
-
-
-/******************************************************************************
-*************************** Begin AFP Locking *********************************
-**
-** AFP is the Apple Filing Protocol.  AFP is a network filesystem found
-** on Apple Macintosh computers - both OS9 and OSX.
-**
-** Third-party implementations of AFP are available.  But this code here
-** only works on OSX.
-*/
-
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-/*
-** The afpLockingContext structure contains all afp lock specific state
-*/
-typedef struct afpLockingContext afpLockingContext;
-struct afpLockingContext {
-  int reserved;
-  const char *dbPath;             /* Name of the open file */
-};
-
-struct ByteRangeLockPB2
-{
-  unsigned long long offset;        /* offset to first byte to lock */
-  unsigned long long length;        /* nbr of bytes to lock */
-  unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */
-  unsigned char unLockFlag;         /* 1 = unlock, 0 = lock */
-  unsigned char startEndFlag;       /* 1=rel to end of fork, 0=rel to start */
-  int fd;                           /* file desc to assoc this lock with */
-};
-
-#define afpfsByteRangeLock2FSCTL        _IOWR('z', 23, struct ByteRangeLockPB2)
-
-/*
-** This is a utility for setting or clearing a bit-range lock on an
-** AFP filesystem.
-** 
-** Return SQLITE_OK on success, SQLITE_BUSY on failure.
-*/
-static int afpSetLock(
-  const char *path,              /* Name of the file to be locked or unlocked */
-  unixFile *pFile,               /* Open file descriptor on path */
-  unsigned long long offset,     /* First byte to be locked */
-  unsigned long long length,     /* Number of bytes to lock */
-  int setLockFlag                /* True to set lock.  False to clear lock */
-){
-  struct ByteRangeLockPB2 pb;
-  int err;
-  
-  pb.unLockFlag = setLockFlag ? 0 : 1;
-  pb.startEndFlag = 0;
-  pb.offset = offset;
-  pb.length = length; 
-  pb.fd = pFile->h;
-  
-  OSTRACE(("AFPSETLOCK [%s] for %d%s in range %llx:%llx\n", 
-    (setLockFlag?"ON":"OFF"), pFile->h, (pb.fd==-1?"[testval-1]":""),
-    offset, length));
-  err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
-  if ( err==-1 ) {
-    int rc;
-    int tErrno = errno;
-    OSTRACE(("AFPSETLOCK failed to fsctl() '%s' %d %s\n",
-             path, tErrno, strerror(tErrno)));
-#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
-    rc = SQLITE_BUSY;
-#else
-    rc = sqliteErrorFromPosixError(tErrno,
-                    setLockFlag ? SQLITE_IOERR_LOCK : SQLITE_IOERR_UNLOCK);
-#endif /* SQLITE_IGNORE_AFP_LOCK_ERRORS */
-    if( IS_LOCK_ERROR(rc) ){
-      pFile->lastErrno = tErrno;
-    }
-    return rc;
-  } else {
-    return SQLITE_OK;
-  }
-}
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-*/
-static int afpCheckReservedLock(sqlite3_file *id, int *pResOut){
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-  afpLockingContext *context;
-  
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-  
-  assert( pFile );
-  context = (afpLockingContext *) pFile->lockingContext;
-  if( context->reserved ){
-    *pResOut = 1;
-    return SQLITE_OK;
-  }
-  unixEnterMutex(); /* Because pFile->pInode is shared across threads */
-  
-  /* Check if a thread in this process holds such a lock */
-  if( pFile->pInode->eFileLock>SHARED_LOCK ){
-    reserved = 1;
-  }
-  
-  /* Otherwise see if some other process holds it.
-   */
-  if( !reserved ){
-    /* lock the RESERVED byte */
-    int lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);  
-    if( SQLITE_OK==lrc ){
-      /* if we succeeded in taking the reserved lock, unlock it to restore
-      ** the original state */
-      lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
-    } else {
-      /* if we failed to get the lock then someone else must have it */
-      reserved = 1;
-    }
-    if( IS_LOCK_ERROR(lrc) ){
-      rc=lrc;
-    }
-  }
-  
-  unixLeaveMutex();
-  OSTRACE(("TEST WR-LOCK %d %d %d (afp)\n", pFile->h, rc, reserved));
-  
-  *pResOut = reserved;
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-*/
-static int afpLock(sqlite3_file *id, int eFileLock){
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile*)id;
-  unixInodeInfo *pInode = pFile->pInode;
-  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
-  
-  assert( pFile );
-  OSTRACE(("LOCK    %d %s was %s(%s,%d) pid=%d (afp)\n", pFile->h,
-           azFileLock(eFileLock), azFileLock(pFile->eFileLock),
-           azFileLock(pInode->eFileLock), pInode->nShared , getpid()));
-
-  /* If there is already a lock of this type or more restrictive on the
-  ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as
-  ** unixEnterMutex() hasn't been called yet.
-  */
-  if( pFile->eFileLock>=eFileLock ){
-    OSTRACE(("LOCK    %d %s ok (already held) (afp)\n", pFile->h,
-           azFileLock(eFileLock)));
-    return SQLITE_OK;
-  }
-
-  /* Make sure the locking sequence is correct
-  **  (1) We never move from unlocked to anything higher than shared lock.
-  **  (2) SQLite never explicitly requests a pendig lock.
-  **  (3) A shared lock is always held when a reserve lock is requested.
-  */
-  assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
-  assert( eFileLock!=PENDING_LOCK );
-  assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
-  
-  /* This mutex is needed because pFile->pInode is shared across threads
-  */
-  unixEnterMutex();
-  pInode = pFile->pInode;
-
-  /* If some thread using this PID has a lock via a different unixFile*
-  ** handle that precludes the requested lock, return BUSY.
-  */
-  if( (pFile->eFileLock!=pInode->eFileLock && 
-       (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
-     ){
-    rc = SQLITE_BUSY;
-    goto afp_end_lock;
-  }
-  
-  /* If a SHARED lock is requested, and some thread using this PID already
-  ** has a SHARED or RESERVED lock, then increment reference counts and
-  ** return SQLITE_OK.
-  */
-  if( eFileLock==SHARED_LOCK && 
-     (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
-    assert( eFileLock==SHARED_LOCK );
-    assert( pFile->eFileLock==0 );
-    assert( pInode->nShared>0 );
-    pFile->eFileLock = SHARED_LOCK;
-    pInode->nShared++;
-    pInode->nLock++;
-    goto afp_end_lock;
-  }
-    
-  /* A PENDING lock is needed before acquiring a SHARED lock and before
-  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
-  ** be released.
-  */
-  if( eFileLock==SHARED_LOCK 
-      || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLock<PENDING_LOCK)
-  ){
-    int failed;
-    failed = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 1);
-    if (failed) {
-      rc = failed;
-      goto afp_end_lock;
-    }
-  }
-  
-  /* If control gets to this point, then actually go ahead and make
-  ** operating system calls for the specified lock.
-  */
-  if( eFileLock==SHARED_LOCK ){
-    int lrc1, lrc2, lrc1Errno = 0;
-    long lk, mask;
-    
-    assert( pInode->nShared==0 );
-    assert( pInode->eFileLock==0 );
-        
-    mask = (sizeof(long)==8) ? LARGEST_INT64 : 0x7fffffff;
-    /* Now get the read-lock SHARED_LOCK */
-    /* note that the quality of the randomness doesn't matter that much */
-    lk = random(); 
-    pInode->sharedByte = (lk & mask)%(SHARED_SIZE - 1);
-    lrc1 = afpSetLock(context->dbPath, pFile, 
-          SHARED_FIRST+pInode->sharedByte, 1, 1);
-    if( IS_LOCK_ERROR(lrc1) ){
-      lrc1Errno = pFile->lastErrno;
-    }
-    /* Drop the temporary PENDING lock */
-    lrc2 = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
-    
-    if( IS_LOCK_ERROR(lrc1) ) {
-      pFile->lastErrno = lrc1Errno;
-      rc = lrc1;
-      goto afp_end_lock;
-    } else if( IS_LOCK_ERROR(lrc2) ){
-      rc = lrc2;
-      goto afp_end_lock;
-    } else if( lrc1 != SQLITE_OK ) {
-      rc = lrc1;
-    } else {
-      pFile->eFileLock = SHARED_LOCK;
-      pInode->nLock++;
-      pInode->nShared = 1;
-    }
-  }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
-    /* We are trying for an exclusive lock but another thread in this
-     ** same process is still holding a shared lock. */
-    rc = SQLITE_BUSY;
-  }else{
-    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
-    ** assumed that there is a SHARED or greater lock on the file
-    ** already.
-    */
-    int failed = 0;
-    assert( 0!=pFile->eFileLock );
-    if (eFileLock >= RESERVED_LOCK && pFile->eFileLock < RESERVED_LOCK) {
-        /* Acquire a RESERVED lock */
-        failed = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
-      if( !failed ){
-        context->reserved = 1;
-      }
-    }
-    if (!failed && eFileLock == EXCLUSIVE_LOCK) {
-      /* Acquire an EXCLUSIVE lock */
-        
-      /* Remove the shared lock before trying the range.  we'll need to 
-      ** reestablish the shared lock if we can't get the  afpUnlock
-      */
-      if( !(failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST +
-                         pInode->sharedByte, 1, 0)) ){
-        int failed2 = SQLITE_OK;
-        /* now attemmpt to get the exclusive lock range */
-        failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST, 
-                               SHARED_SIZE, 1);
-        if( failed && (failed2 = afpSetLock(context->dbPath, pFile, 
-                       SHARED_FIRST + pInode->sharedByte, 1, 1)) ){
-          /* Can't reestablish the shared lock.  Sqlite can't deal, this is
-          ** a critical I/O error
-          */
-          rc = ((failed & SQLITE_IOERR) == SQLITE_IOERR) ? failed2 : 
-               SQLITE_IOERR_LOCK;
-          goto afp_end_lock;
-        } 
-      }else{
-        rc = failed; 
-      }
-    }
-    if( failed ){
-      rc = failed;
-    }
-  }
-  
-  if( rc==SQLITE_OK ){
-    pFile->eFileLock = eFileLock;
-    pInode->eFileLock = eFileLock;
-  }else if( eFileLock==EXCLUSIVE_LOCK ){
-    pFile->eFileLock = PENDING_LOCK;
-    pInode->eFileLock = PENDING_LOCK;
-  }
-  
-afp_end_lock:
-  unixLeaveMutex();
-  OSTRACE(("LOCK    %d %s %s (afp)\n", pFile->h, azFileLock(eFileLock), 
-         rc==SQLITE_OK ? "ok" : "failed"));
-  return rc;
-}
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-*/
-static int afpUnlock(sqlite3_file *id, int eFileLock) {
-  int rc = SQLITE_OK;
-  unixFile *pFile = (unixFile*)id;
-  unixInodeInfo *pInode;
-  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
-  int skipShared = 0;
-#ifdef SQLITE_TEST
-  int h = pFile->h;
-#endif
-
-  assert( pFile );
-  OSTRACE(("UNLOCK  %d %d was %d(%d,%d) pid=%d (afp)\n", pFile->h, eFileLock,
-           pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
-           getpid()));
-
-  assert( eFileLock<=SHARED_LOCK );
-  if( pFile->eFileLock<=eFileLock ){
-    return SQLITE_OK;
-  }
-  unixEnterMutex();
-  pInode = pFile->pInode;
-  assert( pInode->nShared!=0 );
-  if( pFile->eFileLock>SHARED_LOCK ){
-    assert( pInode->eFileLock==pFile->eFileLock );
-    SimulateIOErrorBenign(1);
-    SimulateIOError( h=(-1) )
-    SimulateIOErrorBenign(0);
-    
-#ifdef SQLITE_DEBUG
-    /* When reducing a lock such that other processes can start
-    ** reading the database file again, make sure that the
-    ** transaction counter was updated if any part of the database
-    ** file changed.  If the transaction counter is not updated,
-    ** other connections to the same file might not realize that
-    ** the file has changed and hence might not know to flush their
-    ** cache.  The use of a stale cache can lead to database corruption.
-    */
-    assert( pFile->inNormalWrite==0
-           || pFile->dbUpdate==0
-           || pFile->transCntrChng==1 );
-    pFile->inNormalWrite = 0;
-#endif
-    
-    if( pFile->eFileLock==EXCLUSIVE_LOCK ){
-      rc = afpSetLock(context->dbPath, pFile, SHARED_FIRST, SHARED_SIZE, 0);
-      if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1) ){
-        /* only re-establish the shared lock if necessary */
-        int sharedLockByte = SHARED_FIRST+pInode->sharedByte;
-        rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 1);
-      } else {
-        skipShared = 1;
-      }
-    }
-    if( rc==SQLITE_OK && pFile->eFileLock>=PENDING_LOCK ){
-      rc = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
-    } 
-    if( rc==SQLITE_OK && pFile->eFileLock>=RESERVED_LOCK && context->reserved ){
-      rc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
-      if( !rc ){ 
-        context->reserved = 0; 
-      }
-    }
-    if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1)){
-      pInode->eFileLock = SHARED_LOCK;
-    }
-  }
-  if( rc==SQLITE_OK && eFileLock==NO_LOCK ){
-
-    /* Decrement the shared lock counter.  Release the lock using an
-    ** OS call only when all threads in this same process have released
-    ** the lock.
-    */
-    unsigned long long sharedLockByte = SHARED_FIRST+pInode->sharedByte;
-    pInode->nShared--;
-    if( pInode->nShared==0 ){
-      SimulateIOErrorBenign(1);
-      SimulateIOError( h=(-1) )
-      SimulateIOErrorBenign(0);
-      if( !skipShared ){
-        rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 0);
-      }
-      if( !rc ){
-        pInode->eFileLock = NO_LOCK;
-        pFile->eFileLock = NO_LOCK;
-      }
-    }
-    if( rc==SQLITE_OK ){
-      pInode->nLock--;
-      assert( pInode->nLock>=0 );
-      if( pInode->nLock==0 ){
-        closePendingFds(pFile);
-      }
-    }
-  }
-  
-  unixLeaveMutex();
-  if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
-  return rc;
-}
-
-/*
-** Close a file & cleanup AFP specific locking context 
-*/
-static int afpClose(sqlite3_file *id) {
-  int rc = SQLITE_OK;
-  if( id ){
-    unixFile *pFile = (unixFile*)id;
-    afpUnlock(id, NO_LOCK);
-    unixEnterMutex();
-    if( pFile->pInode && pFile->pInode->nLock ){
-      /* If there are outstanding locks, do not actually close the file just
-      ** yet because that would clear those locks.  Instead, add the file
-      ** descriptor to pInode->aPending.  It will be automatically closed when
-      ** the last lock is cleared.
-      */
-      setPendingFd(pFile);
-    }
-    releaseInodeInfo(pFile);
-    sqlite3_free(pFile->lockingContext);
-    rc = closeUnixFile(id);
-    unixLeaveMutex();
-  }
-  return rc;
-}
-
-#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
-/*
-** The code above is the AFP lock implementation.  The code is specific
-** to MacOSX and does not work on other unix platforms.  No alternative
-** is available.  If you don't compile for a mac, then the "unix-afp"
-** VFS is not available.
-**
-********************* End of the AFP lock implementation **********************
-******************************************************************************/
-
-/******************************************************************************
-*************************** Begin NFS Locking ********************************/
-
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-/*
- ** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
- ** must be either NO_LOCK or SHARED_LOCK.
- **
- ** If the locking level of the file descriptor is already at or below
- ** the requested locking level, this routine is a no-op.
- */
-static int nfsUnlock(sqlite3_file *id, int eFileLock){
-  return posixUnlock(id, eFileLock, 1);
-}
-
-#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
-/*
-** The code above is the NFS lock implementation.  The code is specific
-** to MacOSX and does not work on other unix platforms.  No alternative
-** is available.  
-**
-********************* End of the NFS lock implementation **********************
-******************************************************************************/
-
-/******************************************************************************
-**************** Non-locking sqlite3_file methods *****************************
-**
-** The next division contains implementations for all methods of the 
-** sqlite3_file object other than the locking methods.  The locking
-** methods were defined in divisions above (one locking method per
-** division).  Those methods that are common to all locking modes
-** are gather together into this division.
-*/
-
-/*
-** Seek to the offset passed as the second argument, then read cnt 
-** bytes into pBuf. Return the number of bytes actually read.
-**
-** NB:  If you define USE_PREAD or USE_PREAD64, then it might also
-** be necessary to define _XOPEN_SOURCE to be 500.  This varies from
-** one system to another.  Since SQLite does not define USE_PREAD
-** any any form by default, we will not attempt to define _XOPEN_SOURCE.
-** See tickets #2741 and #2681.
-**
-** To avoid stomping the errno value on a failed read the lastErrno value
-** is set before returning.
-*/
-static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
-  int got;
-  int prior = 0;
-#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
-  i64 newOffset;
-#endif
-  TIMER_START;
-  assert( cnt==(cnt&0x1ffff) );
-  assert( id->h>2 );
-  cnt &= 0x1ffff;
-  do{
-#if defined(USE_PREAD)
-    got = osPread(id->h, pBuf, cnt, offset);
-    SimulateIOError( got = -1 );
-#elif defined(USE_PREAD64)
-    got = osPread64(id->h, pBuf, cnt, offset);
-    SimulateIOError( got = -1 );
-#else
-    newOffset = lseek(id->h, offset, SEEK_SET);
-    SimulateIOError( newOffset-- );
-    if( newOffset!=offset ){
-      if( newOffset == -1 ){
-        ((unixFile*)id)->lastErrno = errno;
-      }else{
-        ((unixFile*)id)->lastErrno = 0;
-      }
-      return -1;
-    }
-    got = osRead(id->h, pBuf, cnt);
-#endif
-    if( got==cnt ) break;
-    if( got<0 ){
-      if( errno==EINTR ){ got = 1; continue; }
-      prior = 0;
-      ((unixFile*)id)->lastErrno = errno;
-      break;
-    }else if( got>0 ){
-      cnt -= got;
-      offset += got;
-      prior += got;
-      pBuf = (void*)(got + (char*)pBuf);
-    }
-  }while( got>0 );
-  TIMER_END;
-  OSTRACE(("READ    %-3d %5d %7lld %llu\n",
-            id->h, got+prior, offset-prior, TIMER_ELAPSED));
-  return got+prior;
-}
-
-/*
-** Read data from a file into a buffer.  Return SQLITE_OK if all
-** bytes were read successfully and SQLITE_IOERR if anything goes
-** wrong.
-*/
-static int unixRead(
-  sqlite3_file *id, 
-  void *pBuf, 
-  int amt,
-  sqlite3_int64 offset
-){
-  unixFile *pFile = (unixFile *)id;
-  int got;
-  assert( id );
-  assert( offset>=0 );
-  assert( amt>0 );
-
-  /* If this is a database file (not a journal, master-journal or temp
-  ** file), the bytes in the locking range should never be read or written. */
-#if 0
-  assert( pFile->pUnused==0
-       || offset>=PENDING_BYTE+512
-       || offset+amt<=PENDING_BYTE 
-  );
-#endif
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* Deal with as much of this read request as possible by transfering
-  ** data from the memory mapping using memcpy().  */
-  if( offset<pFile->mmapSize ){
-    if( offset+amt <= pFile->mmapSize ){
-      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
-      return SQLITE_OK;
-    }else{
-      int nCopy = pFile->mmapSize - offset;
-      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
-      pBuf = &((u8 *)pBuf)[nCopy];
-      amt -= nCopy;
-      offset += nCopy;
-    }
-  }
-#endif
-
-  got = seekAndRead(pFile, offset, pBuf, amt);
-  if( got==amt ){
-    return SQLITE_OK;
-  }else if( got<0 ){
-    /* lastErrno set by seekAndRead */
-    return SQLITE_IOERR_READ;
-  }else{
-    pFile->lastErrno = 0; /* not a system error */
-    /* Unread parts of the buffer must be zero-filled */
-    memset(&((char*)pBuf)[got], 0, amt-got);
-    return SQLITE_IOERR_SHORT_READ;
-  }
-}
-
-/*
-** Attempt to seek the file-descriptor passed as the first argument to
-** absolute offset iOff, then attempt to write nBuf bytes of data from
-** pBuf to it. If an error occurs, return -1 and set *piErrno. Otherwise, 
-** return the actual number of bytes written (which may be less than
-** nBuf).
-*/
-static int seekAndWriteFd(
-  int fd,                         /* File descriptor to write to */
-  i64 iOff,                       /* File offset to begin writing at */
-  const void *pBuf,               /* Copy data from this buffer to the file */
-  int nBuf,                       /* Size of buffer pBuf in bytes */
-  int *piErrno                    /* OUT: Error number if error occurs */
-){
-  int rc = 0;                     /* Value returned by system call */
-
-  assert( nBuf==(nBuf&0x1ffff) );
-  assert( fd>2 );
-  nBuf &= 0x1ffff;
-  TIMER_START;
-
-#if defined(USE_PREAD)
-  do{ rc = osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
-#elif defined(USE_PREAD64)
-  do{ rc = osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
-#else
-  do{
-    i64 iSeek = lseek(fd, iOff, SEEK_SET);
-    SimulateIOError( iSeek-- );
-
-    if( iSeek!=iOff ){
-      if( piErrno ) *piErrno = (iSeek==-1 ? errno : 0);
-      return -1;
-    }
-    rc = osWrite(fd, pBuf, nBuf);
-  }while( rc<0 && errno==EINTR );
-#endif
-
-  TIMER_END;
-  OSTRACE(("WRITE   %-3d %5d %7lld %llu\n", fd, rc, iOff, TIMER_ELAPSED));
-
-  if( rc<0 && piErrno ) *piErrno = errno;
-  return rc;
-}
-
-
-/*
-** Seek to the offset in id->offset then read cnt bytes into pBuf.
-** Return the number of bytes actually read.  Update the offset.
-**
-** To avoid stomping the errno value on a failed write the lastErrno value
-** is set before returning.
-*/
-static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
-  return seekAndWriteFd(id->h, offset, pBuf, cnt, &id->lastErrno);
-}
-
-
-/*
-** Write data from a buffer into a file.  Return SQLITE_OK on success
-** or some other error code on failure.
-*/
-static int unixWrite(
-  sqlite3_file *id, 
-  const void *pBuf, 
-  int amt,
-  sqlite3_int64 offset 
-){
-  unixFile *pFile = (unixFile*)id;
-  int wrote = 0;
-  assert( id );
-  assert( amt>0 );
-
-  /* If this is a database file (not a journal, master-journal or temp
-  ** file), the bytes in the locking range should never be read or written. */
-#if 0
-  assert( pFile->pUnused==0
-       || offset>=PENDING_BYTE+512
-       || offset+amt<=PENDING_BYTE 
-  );
-#endif
-
-#ifdef SQLITE_DEBUG
-  /* If we are doing a normal write to a database file (as opposed to
-  ** doing a hot-journal rollback or a write to some file other than a
-  ** normal database file) then record the fact that the database
-  ** has changed.  If the transaction counter is modified, record that
-  ** fact too.
-  */
-  if( pFile->inNormalWrite ){
-    pFile->dbUpdate = 1;  /* The database has been modified */
-    if( offset<=24 && offset+amt>=27 ){
-      int rc;
-      char oldCntr[4];
-      SimulateIOErrorBenign(1);
-      rc = seekAndRead(pFile, 24, oldCntr, 4);
-      SimulateIOErrorBenign(0);
-      if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
-        pFile->transCntrChng = 1;  /* The transaction counter has changed */
-      }
-    }
-  }
-#endif
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* Deal with as much of this write request as possible by transfering
-  ** data from the memory mapping using memcpy().  */
-  if( offset<pFile->mmapSize ){
-    if( offset+amt <= pFile->mmapSize ){
-      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
-      return SQLITE_OK;
-    }else{
-      int nCopy = pFile->mmapSize - offset;
-      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
-      pBuf = &((u8 *)pBuf)[nCopy];
-      amt -= nCopy;
-      offset += nCopy;
-    }
-  }
-#endif
-
-  while( amt>0 && (wrote = seekAndWrite(pFile, offset, pBuf, amt))>0 ){
-    amt -= wrote;
-    offset += wrote;
-    pBuf = &((char*)pBuf)[wrote];
-  }
-  SimulateIOError(( wrote=(-1), amt=1 ));
-  SimulateDiskfullError(( wrote=0, amt=1 ));
-
-  if( amt>0 ){
-    if( wrote<0 && pFile->lastErrno!=ENOSPC ){
-      /* lastErrno set by seekAndWrite */
-      return SQLITE_IOERR_WRITE;
-    }else{
-      pFile->lastErrno = 0; /* not a system error */
-      return SQLITE_FULL;
-    }
-  }
-
-  return SQLITE_OK;
-}
-
-#ifdef SQLITE_TEST
-/*
-** Count the number of fullsyncs and normal syncs.  This is used to test
-** that syncs and fullsyncs are occurring at the right times.
-*/
-SQLITE_API int sqlite3_sync_count = 0;
-SQLITE_API int sqlite3_fullsync_count = 0;
-#endif
-
-/*
-** We do not trust systems to provide a working fdatasync().  Some do.
-** Others do no.  To be safe, we will stick with the (slightly slower)
-** fsync(). If you know that your system does support fdatasync() correctly,
-** then simply compile with -Dfdatasync=fdatasync
-*/
-#if !defined(fdatasync)
-# define fdatasync fsync
-#endif
-
-/*
-** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not
-** the F_FULLFSYNC macro is defined.  F_FULLFSYNC is currently
-** only available on Mac OS X.  But that could change.
-*/
-#ifdef F_FULLFSYNC
-# define HAVE_FULLFSYNC 1
-#else
-# define HAVE_FULLFSYNC 0
-#endif
-
-
-/*
-** The fsync() system call does not work as advertised on many
-** unix systems.  The following procedure is an attempt to make
-** it work better.
-**
-** The SQLITE_NO_SYNC macro disables all fsync()s.  This is useful
-** for testing when we want to run through the test suite quickly.
-** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
-** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
-** or power failure will likely corrupt the database file.
-**
-** SQLite sets the dataOnly flag if the size of the file is unchanged.
-** The idea behind dataOnly is that it should only write the file content
-** to disk, not the inode.  We only set dataOnly if the file size is 
-** unchanged since the file size is part of the inode.  However, 
-** Ted Ts'o tells us that fdatasync() will also write the inode if the
-** file size has changed.  The only real difference between fdatasync()
-** and fsync(), Ted tells us, is that fdatasync() will not flush the
-** inode if the mtime or owner or other inode attributes have changed.
-** We only care about the file size, not the other file attributes, so
-** as far as SQLite is concerned, an fdatasync() is always adequate.
-** So, we always use fdatasync() if it is available, regardless of
-** the value of the dataOnly flag.
-*/
-static int full_fsync(int fd, int fullSync, int dataOnly){
-  int rc;
-
-  /* The following "ifdef/elif/else/" block has the same structure as
-  ** the one below. It is replicated here solely to avoid cluttering 
-  ** up the real code with the UNUSED_PARAMETER() macros.
-  */
-#ifdef SQLITE_NO_SYNC
-  UNUSED_PARAMETER(fd);
-  UNUSED_PARAMETER(fullSync);
-  UNUSED_PARAMETER(dataOnly);
-#elif HAVE_FULLFSYNC
-  UNUSED_PARAMETER(dataOnly);
-#else
-  UNUSED_PARAMETER(fullSync);
-  UNUSED_PARAMETER(dataOnly);
-#endif
-
-  /* Record the number of times that we do a normal fsync() and 
-  ** FULLSYNC.  This is used during testing to verify that this procedure
-  ** gets called with the correct arguments.
-  */
-#ifdef SQLITE_TEST
-  if( fullSync ) sqlite3_fullsync_count++;
-  sqlite3_sync_count++;
-#endif
-
-  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
-  ** no-op
-  */
-#ifdef SQLITE_NO_SYNC
-  rc = SQLITE_OK;
-#elif HAVE_FULLFSYNC
-  if( fullSync ){
-    rc = osFcntl(fd, F_FULLFSYNC, 0);
-  }else{
-    rc = 1;
-  }
-  /* If the FULLFSYNC failed, fall back to attempting an fsync().
-  ** It shouldn't be possible for fullfsync to fail on the local 
-  ** file system (on OSX), so failure indicates that FULLFSYNC
-  ** isn't supported for this file system. So, attempt an fsync 
-  ** and (for now) ignore the overhead of a superfluous fcntl call.  
-  ** It'd be better to detect fullfsync support once and avoid 
-  ** the fcntl call every time sync is called.
-  */
-  if( rc ) rc = fsync(fd);
-
-#elif defined(__APPLE__)
-  /* fdatasync() on HFS+ doesn't yet flush the file size if it changed correctly
-  ** so currently we default to the macro that redefines fdatasync to fsync
-  */
-  rc = fsync(fd);
-#else 
-  rc = fdatasync(fd);
-#if OS_VXWORKS
-  if( rc==-1 && errno==ENOTSUP ){
-    rc = fsync(fd);
-  }
-#endif /* OS_VXWORKS */
-#endif /* ifdef SQLITE_NO_SYNC elif HAVE_FULLFSYNC */
-
-  if( OS_VXWORKS && rc!= -1 ){
-    rc = 0;
-  }
-  return rc;
-}
-
-/*
-** Open a file descriptor to the directory containing file zFilename.
-** If successful, *pFd is set to the opened file descriptor and
-** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
-** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
-** value.
-**
-** The directory file descriptor is used for only one thing - to
-** fsync() a directory to make sure file creation and deletion events
-** are flushed to disk.  Such fsyncs are not needed on newer
-** journaling filesystems, but are required on older filesystems.
-**
-** This routine can be overridden using the xSetSysCall interface.
-** The ability to override this routine was added in support of the
-** chromium sandbox.  Opening a directory is a security risk (we are
-** told) so making it overrideable allows the chromium sandbox to
-** replace this routine with a harmless no-op.  To make this routine
-** a no-op, replace it with a stub that returns SQLITE_OK but leaves
-** *pFd set to a negative number.
-**
-** If SQLITE_OK is returned, the caller is responsible for closing
-** the file descriptor *pFd using close().
-*/
-static int openDirectory(const char *zFilename, int *pFd){
-  int ii;
-  int fd = -1;
-  char zDirname[MAX_PATHNAME+1];
-
-  sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
-  for(ii=(int)strlen(zDirname); ii>1 && zDirname[ii]!='/'; ii--);
-  if( ii>0 ){
-    zDirname[ii] = '\0';
-    fd = robust_open(zDirname, O_RDONLY|O_BINARY, 0);
-    if( fd>=0 ){
-      OSTRACE(("OPENDIR %-3d %s\n", fd, zDirname));
-    }
-  }
-  *pFd = fd;
-  return (fd>=0?SQLITE_OK:unixLogError(SQLITE_CANTOPEN_BKPT, "open", zDirname));
-}
-
-/*
-** Make sure all writes to a particular file are committed to disk.
-**
-** If dataOnly==0 then both the file itself and its metadata (file
-** size, access time, etc) are synced.  If dataOnly!=0 then only the
-** file data is synced.
-**
-** Under Unix, also make sure that the directory entry for the file
-** has been created by fsync-ing the directory that contains the file.
-** If we do not do this and we encounter a power failure, the directory
-** entry for the journal might not exist after we reboot.  The next
-** SQLite to access the file will not know that the journal exists (because
-** the directory entry for the journal was never created) and the transaction
-** will not roll back - possibly leading to database corruption.
-*/
-static int unixSync(sqlite3_file *id, int flags){
-  int rc;
-  unixFile *pFile = (unixFile*)id;
-
-  int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
-  int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;
-
-  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
-  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
-      || (flags&0x0F)==SQLITE_SYNC_FULL
-  );
-
-  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
-  ** line is to test that doing so does not cause any problems.
-  */
-  SimulateDiskfullError( return SQLITE_FULL );
-
-  assert( pFile );
-  OSTRACE(("SYNC    %-3d\n", pFile->h));
-  rc = full_fsync(pFile->h, isFullsync, isDataOnly);
-  SimulateIOError( rc=1 );
-  if( rc ){
-    pFile->lastErrno = errno;
-    return unixLogError(SQLITE_IOERR_FSYNC, "full_fsync", pFile->zPath);
-  }
-
-  /* Also fsync the directory containing the file if the DIRSYNC flag
-  ** is set.  This is a one-time occurrence.  Many systems (examples: AIX)
-  ** are unable to fsync a directory, so ignore errors on the fsync.
-  */
-  if( pFile->ctrlFlags & UNIXFILE_DIRSYNC ){
-    int dirfd;
-    OSTRACE(("DIRSYNC %s (have_fullfsync=%d fullsync=%d)\n", pFile->zPath,
-            HAVE_FULLFSYNC, isFullsync));
-    rc = osOpenDirectory(pFile->zPath, &dirfd);
-    if( rc==SQLITE_OK && dirfd>=0 ){
-      full_fsync(dirfd, 0, 0);
-      robust_close(pFile, dirfd, __LINE__);
-    }else if( rc==SQLITE_CANTOPEN ){
-      rc = SQLITE_OK;
-    }
-    pFile->ctrlFlags &= ~UNIXFILE_DIRSYNC;
-  }
-  return rc;
-}
-
-/*
-** Truncate an open file to a specified size
-*/
-static int unixTruncate(sqlite3_file *id, i64 nByte){
-  unixFile *pFile = (unixFile *)id;
-  int rc;
-  assert( pFile );
-  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
-
-  /* If the user has configured a chunk-size for this file, truncate the
-  ** file so that it consists of an integer number of chunks (i.e. the
-  ** actual file size after the operation may be larger than the requested
-  ** size).
-  */
-  if( pFile->szChunk>0 ){
-    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
-  }
-
-  rc = robust_ftruncate(pFile->h, (off_t)nByte);
-  if( rc ){
-    pFile->lastErrno = errno;
-    return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
-  }else{
-#ifdef SQLITE_DEBUG
-    /* If we are doing a normal write to a database file (as opposed to
-    ** doing a hot-journal rollback or a write to some file other than a
-    ** normal database file) and we truncate the file to zero length,
-    ** that effectively updates the change counter.  This might happen
-    ** when restoring a database using the backup API from a zero-length
-    ** source.
-    */
-    if( pFile->inNormalWrite && nByte==0 ){
-      pFile->transCntrChng = 1;
-    }
-#endif
-
-#if SQLITE_MAX_MMAP_SIZE>0
-    /* If the file was just truncated to a size smaller than the currently
-    ** mapped region, reduce the effective mapping size as well. SQLite will
-    ** use read() and write() to access data beyond this point from now on.  
-    */
-    if( nByte<pFile->mmapSize ){
-      pFile->mmapSize = nByte;
-    }
-#endif
-
-    return SQLITE_OK;
-  }
-}
-
-/*
-** Determine the current size of a file in bytes
-*/
-static int unixFileSize(sqlite3_file *id, i64 *pSize){
-  int rc;
-  struct stat buf;
-  assert( id );
-  rc = osFstat(((unixFile*)id)->h, &buf);
-  SimulateIOError( rc=1 );
-  if( rc!=0 ){
-    ((unixFile*)id)->lastErrno = errno;
-    return SQLITE_IOERR_FSTAT;
-  }
-  *pSize = buf.st_size;
-
-  /* When opening a zero-size database, the findInodeInfo() procedure
-  ** writes a single byte into that file in order to work around a bug
-  ** in the OS-X msdos filesystem.  In order to avoid problems with upper
-  ** layers, we need to report this file size as zero even though it is
-  ** really 1.   Ticket #3260.
-  */
-  if( *pSize==1 ) *pSize = 0;
-
-
-  return SQLITE_OK;
-}
-
-#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
-/*
-** Handler for proxy-locking file-control verbs.  Defined below in the
-** proxying locking division.
-*/
-static int proxyFileControl(sqlite3_file*,int,void*);
-#endif
-
-/* 
-** This function is called to handle the SQLITE_FCNTL_SIZE_HINT 
-** file-control operation.  Enlarge the database to nBytes in size
-** (rounded up to the next chunk-size).  If the database is already
-** nBytes or larger, this routine is a no-op.
-*/
-static int fcntlSizeHint(unixFile *pFile, i64 nByte){
-  if( pFile->szChunk>0 ){
-    i64 nSize;                    /* Required file size */
-    struct stat buf;              /* Used to hold return values of fstat() */
-   
-    if( osFstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;
-
-    nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
-    if( nSize>(i64)buf.st_size ){
-
-#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
-      /* The code below is handling the return value of osFallocate() 
-      ** correctly. posix_fallocate() is defined to "returns zero on success, 
-      ** or an error number on  failure". See the manpage for details. */
-      int err;
-      do{
-        err = osFallocate(pFile->h, buf.st_size, nSize-buf.st_size);
-      }while( err==EINTR );
-      if( err ) return SQLITE_IOERR_WRITE;
-#else
-      /* If the OS does not have posix_fallocate(), fake it. First use
-      ** ftruncate() to set the file size, then write a single byte to
-      ** the last byte in each block within the extended region. This
-      ** is the same technique used by glibc to implement posix_fallocate()
-      ** on systems that do not have a real fallocate() system call.
-      */
-      int nBlk = buf.st_blksize;  /* File-system block size */
-      i64 iWrite;                 /* Next offset to write to */
-
-      if( robust_ftruncate(pFile->h, nSize) ){
-        pFile->lastErrno = errno;
-        return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
-      }
-      iWrite = ((buf.st_size + 2*nBlk - 1)/nBlk)*nBlk-1;
-      while( iWrite<nSize ){
-        int nWrite = seekAndWrite(pFile, iWrite, "", 1);
-        if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
-        iWrite += nBlk;
-      }
-#endif
-    }
-  }
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
-    int rc;
-    if( pFile->szChunk<=0 ){
-      if( robust_ftruncate(pFile->h, nByte) ){
-        pFile->lastErrno = errno;
-        return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
-      }
-    }
-
-    rc = unixMapfile(pFile, nByte);
-    return rc;
-  }
-#endif
-
-  return SQLITE_OK;
-}
-
-/*
-** If *pArg is inititially negative then this is a query.  Set *pArg to
-** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
-**
-** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
-*/
-static void unixModeBit(unixFile *pFile, unsigned char mask, int *pArg){
-  if( *pArg<0 ){
-    *pArg = (pFile->ctrlFlags & mask)!=0;
-  }else if( (*pArg)==0 ){
-    pFile->ctrlFlags &= ~mask;
-  }else{
-    pFile->ctrlFlags |= mask;
-  }
-}
-
-/* Forward declaration */
-static int unixGetTempname(int nBuf, char *zBuf);
-
-/*
-** Information and control of an open file handle.
-*/
-static int unixFileControl(sqlite3_file *id, int op, void *pArg){
-  unixFile *pFile = (unixFile*)id;
-  switch( op ){
-    case SQLITE_FCNTL_LOCKSTATE: {
-      *(int*)pArg = pFile->eFileLock;
-      return SQLITE_OK;
-    }
-    case SQLITE_LAST_ERRNO: {
-      *(int*)pArg = pFile->lastErrno;
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_CHUNK_SIZE: {
-      pFile->szChunk = *(int *)pArg;
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_SIZE_HINT: {
-      int rc;
-      SimulateIOErrorBenign(1);
-      rc = fcntlSizeHint(pFile, *(i64 *)pArg);
-      SimulateIOErrorBenign(0);
-      return rc;
-    }
-    case SQLITE_FCNTL_PERSIST_WAL: {
-      unixModeBit(pFile, UNIXFILE_PERSIST_WAL, (int*)pArg);
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
-      unixModeBit(pFile, UNIXFILE_PSOW, (int*)pArg);
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_VFSNAME: {
-      *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_TEMPFILENAME: {
-      char *zTFile = sqlite3_malloc( pFile->pVfs->mxPathname );
-      if( zTFile ){
-        unixGetTempname(pFile->pVfs->mxPathname, zTFile);
-        *(char**)pArg = zTFile;
-      }
-      return SQLITE_OK;
-    }
-#if SQLITE_MAX_MMAP_SIZE>0
-    case SQLITE_FCNTL_MMAP_SIZE: {
-      i64 newLimit = *(i64*)pArg;
-      int rc = SQLITE_OK;
-      if( newLimit>sqlite3GlobalConfig.mxMmap ){
-        newLimit = sqlite3GlobalConfig.mxMmap;
-      }
-      *(i64*)pArg = pFile->mmapSizeMax;
-      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
-        pFile->mmapSizeMax = newLimit;
-        if( pFile->mmapSize>0 ){
-          unixUnmapfile(pFile);
-          rc = unixMapfile(pFile, -1);
-        }
-      }
-      return rc;
-    }
-#endif
-#ifdef SQLITE_DEBUG
-    /* The pager calls this method to signal that it has done
-    ** a rollback and that the database is therefore unchanged and
-    ** it hence it is OK for the transaction change counter to be
-    ** unchanged.
-    */
-    case SQLITE_FCNTL_DB_UNCHANGED: {
-      ((unixFile*)id)->dbUpdate = 0;
-      return SQLITE_OK;
-    }
-#endif
-#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
-    case SQLITE_SET_LOCKPROXYFILE:
-    case SQLITE_GET_LOCKPROXYFILE: {
-      return proxyFileControl(id,op,pArg);
-    }
-#endif /* SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__) */
-  }
-  return SQLITE_NOTFOUND;
-}
-
-/*
-** Return the sector size in bytes of the underlying block device for
-** the specified file. This is almost always 512 bytes, but may be
-** larger for some devices.
-**
-** SQLite code assumes this function cannot fail. It also assumes that
-** if two files are created in the same file-system directory (i.e.
-** a database and its journal file) that the sector size will be the
-** same for both.
-*/
-#ifndef __QNXNTO__ 
-static int unixSectorSize(sqlite3_file *NotUsed){
-  UNUSED_PARAMETER(NotUsed);
-  return SQLITE_DEFAULT_SECTOR_SIZE;
-}
-#endif
-
-/*
-** The following version of unixSectorSize() is optimized for QNX.
-*/
-#ifdef __QNXNTO__
-#include <sys/dcmd_blk.h>
-#include <sys/statvfs.h>
-static int unixSectorSize(sqlite3_file *id){
-  unixFile *pFile = (unixFile*)id;
-  if( pFile->sectorSize == 0 ){
-    struct statvfs fsInfo;
-       
-    /* Set defaults for non-supported filesystems */
-    pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
-    pFile->deviceCharacteristics = 0;
-    if( fstatvfs(pFile->h, &fsInfo) == -1 ) {
-      return pFile->sectorSize;
-    }
-
-    if( !strcmp(fsInfo.f_basetype, "tmp") ) {
-      pFile->sectorSize = fsInfo.f_bsize;
-      pFile->deviceCharacteristics =
-        SQLITE_IOCAP_ATOMIC4K |       /* All ram filesystem writes are atomic */
-        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
-                                      ** the write succeeds */
-        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
-                                      ** so it is ordered */
-        0;
-    }else if( strstr(fsInfo.f_basetype, "etfs") ){
-      pFile->sectorSize = fsInfo.f_bsize;
-      pFile->deviceCharacteristics =
-        /* etfs cluster size writes are atomic */
-        (pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) |
-        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
-                                      ** the write succeeds */
-        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
-                                      ** so it is ordered */
-        0;
-    }else if( !strcmp(fsInfo.f_basetype, "qnx6") ){
-      pFile->sectorSize = fsInfo.f_bsize;
-      pFile->deviceCharacteristics =
-        SQLITE_IOCAP_ATOMIC |         /* All filesystem writes are atomic */
-        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
-                                      ** the write succeeds */
-        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
-                                      ** so it is ordered */
-        0;
-    }else if( !strcmp(fsInfo.f_basetype, "qnx4") ){
-      pFile->sectorSize = fsInfo.f_bsize;
-      pFile->deviceCharacteristics =
-        /* full bitset of atomics from max sector size and smaller */
-        ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
-        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
-                                      ** so it is ordered */
-        0;
-    }else if( strstr(fsInfo.f_basetype, "dos") ){
-      pFile->sectorSize = fsInfo.f_bsize;
-      pFile->deviceCharacteristics =
-        /* full bitset of atomics from max sector size and smaller */
-        ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
-        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
-                                      ** so it is ordered */
-        0;
-    }else{
-      pFile->deviceCharacteristics =
-        SQLITE_IOCAP_ATOMIC512 |      /* blocks are atomic */
-        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
-                                      ** the write succeeds */
-        0;
-    }
-  }
-  /* Last chance verification.  If the sector size isn't a multiple of 512
-  ** then it isn't valid.*/
-  if( pFile->sectorSize % 512 != 0 ){
-    pFile->deviceCharacteristics = 0;
-    pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
-  }
-  return pFile->sectorSize;
-}
-#endif /* __QNXNTO__ */
-
-/*
-** Return the device characteristics for the file.
-**
-** This VFS is set up to return SQLITE_IOCAP_POWERSAFE_OVERWRITE by default.
-** However, that choice is contraversial since technically the underlying
-** file system does not always provide powersafe overwrites.  (In other
-** words, after a power-loss event, parts of the file that were never
-** written might end up being altered.)  However, non-PSOW behavior is very,
-** very rare.  And asserting PSOW makes a large reduction in the amount
-** of required I/O for journaling, since a lot of padding is eliminated.
-**  Hence, while POWERSAFE_OVERWRITE is on by default, there is a file-control
-** available to turn it off and URI query parameter available to turn it off.
-*/
-static int unixDeviceCharacteristics(sqlite3_file *id){
-  unixFile *p = (unixFile*)id;
-  int rc = 0;
-#ifdef __QNXNTO__
-  if( p->sectorSize==0 ) unixSectorSize(id);
-  rc = p->deviceCharacteristics;
-#endif
-  if( p->ctrlFlags & UNIXFILE_PSOW ){
-    rc |= SQLITE_IOCAP_POWERSAFE_OVERWRITE;
-  }
-  return rc;
-}
-
-#ifndef SQLITE_OMIT_WAL
-
-
-/*
-** Object used to represent an shared memory buffer.  
-**
-** When multiple threads all reference the same wal-index, each thread
-** has its own unixShm object, but they all point to a single instance
-** of this unixShmNode object.  In other words, each wal-index is opened
-** only once per process.
-**
-** Each unixShmNode object is connected to a single unixInodeInfo object.
-** We could coalesce this object into unixInodeInfo, but that would mean
-** every open file that does not use shared memory (in other words, most
-** open files) would have to carry around this extra information.  So
-** the unixInodeInfo object contains a pointer to this unixShmNode object
-** and the unixShmNode object is created only when needed.
-**
-** unixMutexHeld() must be true when creating or destroying
-** this object or while reading or writing the following fields:
-**
-**      nRef
-**
-** The following fields are read-only after the object is created:
-** 
-**      fid
-**      zFilename
-**
-** Either unixShmNode.mutex must be held or unixShmNode.nRef==0 and
-** unixMutexHeld() is true when reading or writing any other field
-** in this structure.
-*/
-struct unixShmNode {
-  unixInodeInfo *pInode;     /* unixInodeInfo that owns this SHM node */
-  sqlite3_mutex *mutex;      /* Mutex to access this object */
-  char *zFilename;           /* Name of the mmapped file */
-  int h;                     /* Open file descriptor */
-  int szRegion;              /* Size of shared-memory regions */
-  u16 nRegion;               /* Size of array apRegion */
-  u8 isReadonly;             /* True if read-only */
-  char **apRegion;           /* Array of mapped shared-memory regions */
-  int nRef;                  /* Number of unixShm objects pointing to this */
-  unixShm *pFirst;           /* All unixShm objects pointing to this */
-#ifdef SQLITE_DEBUG
-  u8 exclMask;               /* Mask of exclusive locks held */
-  u8 sharedMask;             /* Mask of shared locks held */
-  u8 nextShmId;              /* Next available unixShm.id value */
-#endif
-};
-
-/*
-** Structure used internally by this VFS to record the state of an
-** open shared memory connection.
-**
-** The following fields are initialized when this object is created and
-** are read-only thereafter:
-**
-**    unixShm.pFile
-**    unixShm.id
-**
-** All other fields are read/write.  The unixShm.pFile->mutex must be held
-** while accessing any read/write fields.
-*/
-struct unixShm {
-  unixShmNode *pShmNode;     /* The underlying unixShmNode object */
-  unixShm *pNext;            /* Next unixShm with the same unixShmNode */
-  u8 hasMutex;               /* True if holding the unixShmNode mutex */
-  u8 id;                     /* Id of this connection within its unixShmNode */
-  u16 sharedMask;            /* Mask of shared locks held */
-  u16 exclMask;              /* Mask of exclusive locks held */
-};
-
-/*
-** Constants used for locking
-*/
-#define UNIX_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)         /* first lock byte */
-#define UNIX_SHM_DMS    (UNIX_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
-
-/*
-** Apply posix advisory locks for all bytes from ofst through ofst+n-1.
-**
-** Locks block if the mask is exactly UNIX_SHM_C and are non-blocking
-** otherwise.
-*/
-static int unixShmSystemLock(
-  unixShmNode *pShmNode, /* Apply locks to this open shared-memory segment */
-  int lockType,          /* F_UNLCK, F_RDLCK, or F_WRLCK */
-  int ofst,              /* First byte of the locking range */
-  int n                  /* Number of bytes to lock */
-){
-  struct flock f;       /* The posix advisory locking structure */
-  int rc = SQLITE_OK;   /* Result code form fcntl() */
-
-  /* Access to the unixShmNode object is serialized by the caller */
-  assert( sqlite3_mutex_held(pShmNode->mutex) || pShmNode->nRef==0 );
-
-  /* Shared locks never span more than one byte */
-  assert( n==1 || lockType!=F_RDLCK );
-
-  /* Locks are within range */
-  assert( n>=1 && n<SQLITE_SHM_NLOCK );
-
-  if( pShmNode->h>=0 ){
-    /* Initialize the locking parameters */
-    memset(&f, 0, sizeof(f));
-    f.l_type = lockType;
-    f.l_whence = SEEK_SET;
-    f.l_start = ofst;
-    f.l_len = n;
-
-    rc = osFcntl(pShmNode->h, F_SETLK, &f);
-    rc = (rc!=(-1)) ? SQLITE_OK : SQLITE_BUSY;
-  }
-
-  /* Update the global lock state and do debug tracing */
-#ifdef SQLITE_DEBUG
-  { u16 mask;
-  OSTRACE(("SHM-LOCK "));
-  mask = (1<<(ofst+n)) - (1<<ofst);
-  if( rc==SQLITE_OK ){
-    if( lockType==F_UNLCK ){
-      OSTRACE(("unlock %d ok", ofst));
-      pShmNode->exclMask &= ~mask;
-      pShmNode->sharedMask &= ~mask;
-    }else if( lockType==F_RDLCK ){
-      OSTRACE(("read-lock %d ok", ofst));
-      pShmNode->exclMask &= ~mask;
-      pShmNode->sharedMask |= mask;
-    }else{
-      assert( lockType==F_WRLCK );
-      OSTRACE(("write-lock %d ok", ofst));
-      pShmNode->exclMask |= mask;
-      pShmNode->sharedMask &= ~mask;
-    }
-  }else{
-    if( lockType==F_UNLCK ){
-      OSTRACE(("unlock %d failed", ofst));
-    }else if( lockType==F_RDLCK ){
-      OSTRACE(("read-lock failed"));
-    }else{
-      assert( lockType==F_WRLCK );
-      OSTRACE(("write-lock %d failed", ofst));
-    }
-  }
-  OSTRACE((" - afterwards %03x,%03x\n",
-           pShmNode->sharedMask, pShmNode->exclMask));
-  }
-#endif
-
-  return rc;        
-}
-
-
-/*
-** Purge the unixShmNodeList list of all entries with unixShmNode.nRef==0.
-**
-** This is not a VFS shared-memory method; it is a utility function called
-** by VFS shared-memory methods.
-*/
-static void unixShmPurge(unixFile *pFd){
-  unixShmNode *p = pFd->pInode->pShmNode;
-  assert( unixMutexHeld() );
-  if( p && p->nRef==0 ){
-    int i;
-    assert( p->pInode==pFd->pInode );
-    sqlite3_mutex_free(p->mutex);
-    for(i=0; i<p->nRegion; i++){
-      if( p->h>=0 ){
-        osMunmap(p->apRegion[i], p->szRegion);
-      }else{
-        sqlite3_free(p->apRegion[i]);
-      }
-    }
-    sqlite3_free(p->apRegion);
-    if( p->h>=0 ){
-      robust_close(pFd, p->h, __LINE__);
-      p->h = -1;
-    }
-    p->pInode->pShmNode = 0;
-    sqlite3_free(p);
-  }
-}
-
-/*
-** Open a shared-memory area associated with open database file pDbFd.  
-** This particular implementation uses mmapped files.
-**
-** The file used to implement shared-memory is in the same directory
-** as the open database file and has the same name as the open database
-** file with the "-shm" suffix added.  For example, if the database file
-** is "/home/user1/config.db" then the file that is created and mmapped
-** for shared memory will be called "/home/user1/config.db-shm".  
-**
-** Another approach to is to use files in /dev/shm or /dev/tmp or an
-** some other tmpfs mount. But if a file in a different directory
-** from the database file is used, then differing access permissions
-** or a chroot() might cause two different processes on the same
-** database to end up using different files for shared memory - 
-** meaning that their memory would not really be shared - resulting
-** in database corruption.  Nevertheless, this tmpfs file usage
-** can be enabled at compile-time using -DSQLITE_SHM_DIRECTORY="/dev/shm"
-** or the equivalent.  The use of the SQLITE_SHM_DIRECTORY compile-time
-** option results in an incompatible build of SQLite;  builds of SQLite
-** that with differing SQLITE_SHM_DIRECTORY settings attempt to use the
-** same database file at the same time, database corruption will likely
-** result. The SQLITE_SHM_DIRECTORY compile-time option is considered
-** "unsupported" and may go away in a future SQLite release.
-**
-** When opening a new shared-memory file, if no other instances of that
-** file are currently open, in this process or in other processes, then
-** the file must be truncated to zero length or have its header cleared.
-**
-** If the original database file (pDbFd) is using the "unix-excl" VFS
-** that means that an exclusive lock is held on the database file and
-** that no other processes are able to read or write the database.  In
-** that case, we do not really need shared memory.  No shared memory
-** file is created.  The shared memory will be simulated with heap memory.
-*/
-static int unixOpenSharedMemory(unixFile *pDbFd){
-  struct unixShm *p = 0;          /* The connection to be opened */
-  struct unixShmNode *pShmNode;   /* The underlying mmapped file */
-  int rc;                         /* Result code */
-  unixInodeInfo *pInode;          /* The inode of fd */
-  char *zShmFilename;             /* Name of the file used for SHM */
-  int nShmFilename;               /* Size of the SHM filename in bytes */
-
-  /* Allocate space for the new unixShm object. */
-  p = sqlite3_malloc( sizeof(*p) );
-  if( p==0 ) return SQLITE_NOMEM;
-  memset(p, 0, sizeof(*p));
-  assert( pDbFd->pShm==0 );
-
-  /* Check to see if a unixShmNode object already exists. Reuse an existing
-  ** one if present. Create a new one if necessary.
-  */
-  unixEnterMutex();
-  pInode = pDbFd->pInode;
-  pShmNode = pInode->pShmNode;
-  if( pShmNode==0 ){
-    struct stat sStat;                 /* fstat() info for database file */
-
-    /* Call fstat() to figure out the permissions on the database file. If
-    ** a new *-shm file is created, an attempt will be made to create it
-    ** with the same permissions.
-    */
-    if( osFstat(pDbFd->h, &sStat) && pInode->bProcessLock==0 ){
-      rc = SQLITE_IOERR_FSTAT;
-      goto shm_open_err;
-    }
-
-#ifdef SQLITE_SHM_DIRECTORY
-    nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 31;
-#else
-    nShmFilename = 6 + (int)strlen(pDbFd->zPath);
-#endif
-    pShmNode = sqlite3_malloc( sizeof(*pShmNode) + nShmFilename );
-    if( pShmNode==0 ){
-      rc = SQLITE_NOMEM;
-      goto shm_open_err;
-    }
-    memset(pShmNode, 0, sizeof(*pShmNode)+nShmFilename);
-    zShmFilename = pShmNode->zFilename = (char*)&pShmNode[1];
-#ifdef SQLITE_SHM_DIRECTORY
-    sqlite3_snprintf(nShmFilename, zShmFilename, 
-                     SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
-                     (u32)sStat.st_ino, (u32)sStat.st_dev);
-#else
-    sqlite3_snprintf(nShmFilename, zShmFilename, "%s-shm", pDbFd->zPath);
-    sqlite3FileSuffix3(pDbFd->zPath, zShmFilename);
-#endif
-    pShmNode->h = -1;
-    pDbFd->pInode->pShmNode = pShmNode;
-    pShmNode->pInode = pDbFd->pInode;
-    pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
-    if( pShmNode->mutex==0 ){
-      rc = SQLITE_NOMEM;
-      goto shm_open_err;
-    }
-
-    if( pInode->bProcessLock==0 ){
-      int openFlags = O_RDWR | O_CREAT;
-      if( sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
-        openFlags = O_RDONLY;
-        pShmNode->isReadonly = 1;
-      }
-      pShmNode->h = robust_open(zShmFilename, openFlags, (sStat.st_mode&0777));
-      if( pShmNode->h<0 ){
-        rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zShmFilename);
-        goto shm_open_err;
-      }
-
-      /* If this process is running as root, make sure that the SHM file
-      ** is owned by the same user that owns the original database.  Otherwise,
-      ** the original owner will not be able to connect.
-      */
-      osFchown(pShmNode->h, sStat.st_uid, sStat.st_gid);
-  
-      /* Check to see if another process is holding the dead-man switch.
-      ** If not, truncate the file to zero length. 
-      */
-      rc = SQLITE_OK;
-      if( unixShmSystemLock(pShmNode, F_WRLCK, UNIX_SHM_DMS, 1)==SQLITE_OK ){
-        if( robust_ftruncate(pShmNode->h, 0) ){
-          rc = unixLogError(SQLITE_IOERR_SHMOPEN, "ftruncate", zShmFilename);
-        }
-      }
-      if( rc==SQLITE_OK ){
-        rc = unixShmSystemLock(pShmNode, F_RDLCK, UNIX_SHM_DMS, 1);
-      }
-      if( rc ) goto shm_open_err;
-    }
-  }
-
-  /* Make the new connection a child of the unixShmNode */
-  p->pShmNode = pShmNode;
-#ifdef SQLITE_DEBUG
-  p->id = pShmNode->nextShmId++;
-#endif
-  pShmNode->nRef++;
-  pDbFd->pShm = p;
-  unixLeaveMutex();
-
-  /* The reference count on pShmNode has already been incremented under
-  ** the cover of the unixEnterMutex() mutex and the pointer from the
-  ** new (struct unixShm) object to the pShmNode has been set. All that is
-  ** left to do is to link the new object into the linked list starting
-  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
-  ** mutex.
-  */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  p->pNext = pShmNode->pFirst;
-  pShmNode->pFirst = p;
-  sqlite3_mutex_leave(pShmNode->mutex);
-  return SQLITE_OK;
-
-  /* Jump here on any error */
-shm_open_err:
-  unixShmPurge(pDbFd);       /* This call frees pShmNode if required */
-  sqlite3_free(p);
-  unixLeaveMutex();
-  return rc;
-}
-
-/*
-** This function is called to obtain a pointer to region iRegion of the 
-** shared-memory associated with the database file fd. Shared-memory regions 
-** are numbered starting from zero. Each shared-memory region is szRegion 
-** bytes in size.
-**
-** If an error occurs, an error code is returned and *pp is set to NULL.
-**
-** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
-** region has not been allocated (by any client, including one running in a
-** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
-** bExtend is non-zero and the requested shared-memory region has not yet 
-** been allocated, it is allocated by this function.
-**
-** If the shared-memory region has already been allocated or is allocated by
-** this call as described above, then it is mapped into this processes 
-** address space (if it is not already), *pp is set to point to the mapped 
-** memory and SQLITE_OK returned.
-*/
-static int unixShmMap(
-  sqlite3_file *fd,               /* Handle open on database file */
-  int iRegion,                    /* Region to retrieve */
-  int szRegion,                   /* Size of regions */
-  int bExtend,                    /* True to extend file if necessary */
-  void volatile **pp              /* OUT: Mapped memory */
-){
-  unixFile *pDbFd = (unixFile*)fd;
-  unixShm *p;
-  unixShmNode *pShmNode;
-  int rc = SQLITE_OK;
-
-  /* If the shared-memory file has not yet been opened, open it now. */
-  if( pDbFd->pShm==0 ){
-    rc = unixOpenSharedMemory(pDbFd);
-    if( rc!=SQLITE_OK ) return rc;
-  }
-
-  p = pDbFd->pShm;
-  pShmNode = p->pShmNode;
-  sqlite3_mutex_enter(pShmNode->mutex);
-  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
-  assert( pShmNode->pInode==pDbFd->pInode );
-  assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
-  assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
-
-  if( pShmNode->nRegion<=iRegion ){
-    char **apNew;                      /* New apRegion[] array */
-    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
-    struct stat sStat;                 /* Used by fstat() */
-
-    pShmNode->szRegion = szRegion;
-
-    if( pShmNode->h>=0 ){
-      /* The requested region is not mapped into this processes address space.
-      ** Check to see if it has been allocated (i.e. if the wal-index file is
-      ** large enough to contain the requested region).
-      */
-      if( osFstat(pShmNode->h, &sStat) ){
-        rc = SQLITE_IOERR_SHMSIZE;
-        goto shmpage_out;
-      }
-  
-      if( sStat.st_size<nByte ){
-        /* The requested memory region does not exist. If bExtend is set to
-        ** false, exit early. *pp will be set to NULL and SQLITE_OK returned.
-        */
-        if( !bExtend ){
-          goto shmpage_out;
-        }
-
-        /* Alternatively, if bExtend is true, extend the file. Do this by
-        ** writing a single byte to the end of each (OS) page being
-        ** allocated or extended. Technically, we need only write to the
-        ** last page in order to extend the file. But writing to all new
-        ** pages forces the OS to allocate them immediately, which reduces
-        ** the chances of SIGBUS while accessing the mapped region later on.
-        */
-        else{
-          static const int pgsz = 4096;
-          int iPg;
-
-          /* Write to the last byte of each newly allocated or extended page */
-          assert( (nByte % pgsz)==0 );
-          for(iPg=(sStat.st_size/pgsz); iPg<(nByte/pgsz); iPg++){
-            if( seekAndWriteFd(pShmNode->h, iPg*pgsz + pgsz-1, "", 1, 0)!=1 ){
-              const char *zFile = pShmNode->zFilename;
-              rc = unixLogError(SQLITE_IOERR_SHMSIZE, "write", zFile);
-              goto shmpage_out;
-            }
-          }
-        }
-      }
-    }
-
-    /* Map the requested memory region into this processes address space. */
-    apNew = (char **)sqlite3_realloc(
-        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
-    );
-    if( !apNew ){
-      rc = SQLITE_IOERR_NOMEM;
-      goto shmpage_out;
-    }
-    pShmNode->apRegion = apNew;
-    while(pShmNode->nRegion<=iRegion){
-      void *pMem;
-      if( pShmNode->h>=0 ){
-        pMem = osMmap(0, szRegion,
-            pShmNode->isReadonly ? PROT_READ : PROT_READ|PROT_WRITE, 
-            MAP_SHARED, pShmNode->h, szRegion*(i64)pShmNode->nRegion
-        );
-        if( pMem==MAP_FAILED ){
-          rc = unixLogError(SQLITE_IOERR_SHMMAP, "mmap", pShmNode->zFilename);
-          goto shmpage_out;
-        }
-      }else{
-        pMem = sqlite3_malloc(szRegion);
-        if( pMem==0 ){
-          rc = SQLITE_NOMEM;
-          goto shmpage_out;
-        }
-        memset(pMem, 0, szRegion);
-      }
-      pShmNode->apRegion[pShmNode->nRegion] = pMem;
-      pShmNode->nRegion++;
-    }
-  }
-
-shmpage_out:
-  if( pShmNode->nRegion>iRegion ){
-    *pp = pShmNode->apRegion[iRegion];
-  }else{
-    *pp = 0;
-  }
-  if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
-  sqlite3_mutex_leave(pShmNode->mutex);
-  return rc;
-}
-
-/*
-** Change the lock state for a shared-memory segment.
-**
-** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
-** different here than in posix.  In xShmLock(), one can go from unlocked
-** to shared and back or from unlocked to exclusive and back.  But one may
-** not go from shared to exclusive or from exclusive to shared.
-*/
-static int unixShmLock(
-  sqlite3_file *fd,          /* Database file holding the shared memory */
-  int ofst,                  /* First lock to acquire or release */
-  int n,                     /* Number of locks to acquire or release */
-  int flags                  /* What to do with the lock */
-){
-  unixFile *pDbFd = (unixFile*)fd;      /* Connection holding shared memory */
-  unixShm *p = pDbFd->pShm;             /* The shared memory being locked */
-  unixShm *pX;                          /* For looping over all siblings */
-  unixShmNode *pShmNode = p->pShmNode;  /* The underlying file iNode */
-  int rc = SQLITE_OK;                   /* Result code */
-  u16 mask;                             /* Mask of locks to take or release */
-
-  assert( pShmNode==pDbFd->pInode->pShmNode );
-  assert( pShmNode->pInode==pDbFd->pInode );
-  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
-  assert( n>=1 );
-  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
-  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
-  assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
-  assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
-
-  mask = (1<<(ofst+n)) - (1<<ofst);
-  assert( n>1 || mask==(1<<ofst) );
-  sqlite3_mutex_enter(pShmNode->mutex);
-  if( flags & SQLITE_SHM_UNLOCK ){
-    u16 allMask = 0; /* Mask of locks held by siblings */
-
-    /* See if any siblings hold this same lock */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( pX==p ) continue;
-      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
-      allMask |= pX->sharedMask;
-    }
-
-    /* Unlock the system-level locks */
-    if( (mask & allMask)==0 ){
-      rc = unixShmSystemLock(pShmNode, F_UNLCK, ofst+UNIX_SHM_BASE, n);
-    }else{
-      rc = SQLITE_OK;
-    }
-
-    /* Undo the local locks */
-    if( rc==SQLITE_OK ){
-      p->exclMask &= ~mask;
-      p->sharedMask &= ~mask;
-    } 
-  }else if( flags & SQLITE_SHM_SHARED ){
-    u16 allShared = 0;  /* Union of locks held by connections other than "p" */
-
-    /* Find out which shared locks are already held by sibling connections.
-    ** If any sibling already holds an exclusive lock, go ahead and return
-    ** SQLITE_BUSY.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-      allShared |= pX->sharedMask;
-    }
-
-    /* Get shared locks at the system level, if necessary */
-    if( rc==SQLITE_OK ){
-      if( (allShared & mask)==0 ){
-        rc = unixShmSystemLock(pShmNode, F_RDLCK, ofst+UNIX_SHM_BASE, n);
-      }else{
-        rc = SQLITE_OK;
-      }
-    }
-
-    /* Get the local shared locks */
-    if( rc==SQLITE_OK ){
-      p->sharedMask |= mask;
-    }
-  }else{
-    /* Make sure no sibling connections hold locks that will block this
-    ** lock.  If any do, return SQLITE_BUSY right away.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-    }
-  
-    /* Get the exclusive locks at the system level.  Then if successful
-    ** also mark the local connection as being locked.
-    */
-    if( rc==SQLITE_OK ){
-      rc = unixShmSystemLock(pShmNode, F_WRLCK, ofst+UNIX_SHM_BASE, n);
-      if( rc==SQLITE_OK ){
-        assert( (p->sharedMask & mask)==0 );
-        p->exclMask |= mask;
-      }
-    }
-  }
-  sqlite3_mutex_leave(pShmNode->mutex);
-  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x\n",
-           p->id, getpid(), p->sharedMask, p->exclMask));
-  return rc;
-}
-
-/*
-** Implement a memory barrier or memory fence on shared memory.  
-**
-** All loads and stores begun before the barrier must complete before
-** any load or store begun after the barrier.
-*/
-static void unixShmBarrier(
-  sqlite3_file *fd                /* Database file holding the shared memory */
-){
-  UNUSED_PARAMETER(fd);
-  unixEnterMutex();
-  unixLeaveMutex();
-}
-
-/*
-** Close a connection to shared-memory.  Delete the underlying 
-** storage if deleteFlag is true.
-**
-** If there is no shared memory associated with the connection then this
-** routine is a harmless no-op.
-*/
-static int unixShmUnmap(
-  sqlite3_file *fd,               /* The underlying database file */
-  int deleteFlag                  /* Delete shared-memory if true */
-){
-  unixShm *p;                     /* The connection to be closed */
-  unixShmNode *pShmNode;          /* The underlying shared-memory file */
-  unixShm **pp;                   /* For looping over sibling connections */
-  unixFile *pDbFd;                /* The underlying database file */
-
-  pDbFd = (unixFile*)fd;
-  p = pDbFd->pShm;
-  if( p==0 ) return SQLITE_OK;
-  pShmNode = p->pShmNode;
-
-  assert( pShmNode==pDbFd->pInode->pShmNode );
-  assert( pShmNode->pInode==pDbFd->pInode );
-
-  /* Remove connection p from the set of connections associated
-  ** with pShmNode */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
-  *pp = p->pNext;
-
-  /* Free the connection p */
-  sqlite3_free(p);
-  pDbFd->pShm = 0;
-  sqlite3_mutex_leave(pShmNode->mutex);
-
-  /* If pShmNode->nRef has reached 0, then close the underlying
-  ** shared-memory file, too */
-  unixEnterMutex();
-  assert( pShmNode->nRef>0 );
-  pShmNode->nRef--;
-  if( pShmNode->nRef==0 ){
-    if( deleteFlag && pShmNode->h>=0 ) osUnlink(pShmNode->zFilename);
-    unixShmPurge(pDbFd);
-  }
-  unixLeaveMutex();
-
-  return SQLITE_OK;
-}
-
-
-#else
-# define unixShmMap     0
-# define unixShmLock    0
-# define unixShmBarrier 0
-# define unixShmUnmap   0
-#endif /* #ifndef SQLITE_OMIT_WAL */
-
-#if SQLITE_MAX_MMAP_SIZE>0
-/*
-** If it is currently memory mapped, unmap file pFd.
-*/
-static void unixUnmapfile(unixFile *pFd){
-  assert( pFd->nFetchOut==0 );
-  if( pFd->pMapRegion ){
-    osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
-    pFd->pMapRegion = 0;
-    pFd->mmapSize = 0;
-    pFd->mmapSizeActual = 0;
-  }
-}
-
-/*
-** Return the system page size.
-*/
-static int unixGetPagesize(void){
-#if HAVE_MREMAP
-  return 512;
-#elif defined(_BSD_SOURCE)
-  return getpagesize();
-#else
-  return (int)sysconf(_SC_PAGESIZE);
-#endif
-}
-
-/*
-** Attempt to set the size of the memory mapping maintained by file 
-** descriptor pFd to nNew bytes. Any existing mapping is discarded.
-**
-** If successful, this function sets the following variables:
-**
-**       unixFile.pMapRegion
-**       unixFile.mmapSize
-**       unixFile.mmapSizeActual
-**
-** If unsuccessful, an error message is logged via sqlite3_log() and
-** the three variables above are zeroed. In this case SQLite should
-** continue accessing the database using the xRead() and xWrite()
-** methods.
-*/
-static void unixRemapfile(
-  unixFile *pFd,                  /* File descriptor object */
-  i64 nNew                        /* Required mapping size */
-){
-  const char *zErr = "mmap";
-  int h = pFd->h;                      /* File descriptor open on db file */
-  u8 *pOrig = (u8 *)pFd->pMapRegion;   /* Pointer to current file mapping */
-  i64 nOrig = pFd->mmapSizeActual;     /* Size of pOrig region in bytes */
-  u8 *pNew = 0;                        /* Location of new mapping */
-  int flags = PROT_READ;               /* Flags to pass to mmap() */
-
-  assert( pFd->nFetchOut==0 );
-  assert( nNew>pFd->mmapSize );
-  assert( nNew<=pFd->mmapSizeMax );
-  assert( nNew>0 );
-  assert( pFd->mmapSizeActual>=pFd->mmapSize );
-  assert( MAP_FAILED!=0 );
-
-  if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;
-
-  if( pOrig ){
-    const int szSyspage = unixGetPagesize();
-    i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));
-    u8 *pReq = &pOrig[nReuse];
-
-    /* Unmap any pages of the existing mapping that cannot be reused. */
-    if( nReuse!=nOrig ){
-      osMunmap(pReq, nOrig-nReuse);
-    }
-
-#if HAVE_MREMAP
-    pNew = osMremap(pOrig, nReuse, nNew, MREMAP_MAYMOVE);
-    zErr = "mremap";
-#else
-    pNew = osMmap(pReq, nNew-nReuse, flags, MAP_SHARED, h, nReuse);
-    if( pNew!=MAP_FAILED ){
-      if( pNew!=pReq ){
-        osMunmap(pNew, nNew - nReuse);
-        pNew = 0;
-      }else{
-        pNew = pOrig;
-      }
-    }
-#endif
-
-    /* The attempt to extend the existing mapping failed. Free it. */
-    if( pNew==MAP_FAILED || pNew==0 ){
-      osMunmap(pOrig, nReuse);
-    }
-  }
-
-  /* If pNew is still NULL, try to create an entirely new mapping. */
-  if( pNew==0 ){
-    pNew = osMmap(0, nNew, flags, MAP_SHARED, h, 0);
-  }
-
-  if( pNew==MAP_FAILED ){
-    pNew = 0;
-    nNew = 0;
-    unixLogError(SQLITE_OK, zErr, pFd->zPath);
-
-    /* If the mmap() above failed, assume that all subsequent mmap() calls
-    ** will probably fail too. Fall back to using xRead/xWrite exclusively
-    ** in this case.  */
-    pFd->mmapSizeMax = 0;
-  }
-  pFd->pMapRegion = (void *)pNew;
-  pFd->mmapSize = pFd->mmapSizeActual = nNew;
-}
-
-/*
-** Memory map or remap the file opened by file-descriptor pFd (if the file
-** is already mapped, the existing mapping is replaced by the new). Or, if 
-** there already exists a mapping for this file, and there are still 
-** outstanding xFetch() references to it, this function is a no-op.
-**
-** If parameter nByte is non-negative, then it is the requested size of 
-** the mapping to create. Otherwise, if nByte is less than zero, then the 
-** requested size is the size of the file on disk. The actual size of the
-** created mapping is either the requested size or the value configured 
-** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
-**
-** SQLITE_OK is returned if no error occurs (even if the mapping is not
-** recreated as a result of outstanding references) or an SQLite error
-** code otherwise.
-*/
-static int unixMapfile(unixFile *pFd, i64 nByte){
-  i64 nMap = nByte;
-  int rc;
-
-  assert( nMap>=0 || pFd->nFetchOut==0 );
-  if( pFd->nFetchOut>0 ) return SQLITE_OK;
-
-  if( nMap<0 ){
-    struct stat statbuf;          /* Low-level file information */
-    rc = osFstat(pFd->h, &statbuf);
-    if( rc!=SQLITE_OK ){
-      return SQLITE_IOERR_FSTAT;
-    }
-    nMap = statbuf.st_size;
-  }
-  if( nMap>pFd->mmapSizeMax ){
-    nMap = pFd->mmapSizeMax;
-  }
-
-  if( nMap!=pFd->mmapSize ){
-    if( nMap>0 ){
-      unixRemapfile(pFd, nMap);
-    }else{
-      unixUnmapfile(pFd);
-    }
-  }
-
-  return SQLITE_OK;
-}
-#endif /* SQLITE_MAX_MMAP_SIZE>0 */
-
-/*
-** If possible, return a pointer to a mapping of file fd starting at offset
-** iOff. The mapping must be valid for at least nAmt bytes.
-**
-** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
-** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
-** Finally, if an error does occur, return an SQLite error code. The final
-** value of *pp is undefined in this case.
-**
-** If this function does return a pointer, the caller must eventually 
-** release the reference by calling unixUnfetch().
-*/
-static int unixFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
-#if SQLITE_MAX_MMAP_SIZE>0
-  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
-#endif
-  *pp = 0;
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  if( pFd->mmapSizeMax>0 ){
-    if( pFd->pMapRegion==0 ){
-      int rc = unixMapfile(pFd, -1);
-      if( rc!=SQLITE_OK ) return rc;
-    }
-    if( pFd->mmapSize >= iOff+nAmt ){
-      *pp = &((u8 *)pFd->pMapRegion)[iOff];
-      pFd->nFetchOut++;
-    }
-  }
-#endif
-  return SQLITE_OK;
-}
-
-/*
-** If the third argument is non-NULL, then this function releases a 
-** reference obtained by an earlier call to unixFetch(). The second
-** argument passed to this function must be the same as the corresponding
-** argument that was passed to the unixFetch() invocation. 
-**
-** Or, if the third argument is NULL, then this function is being called 
-** to inform the VFS layer that, according to POSIX, any existing mapping 
-** may now be invalid and should be unmapped.
-*/
-static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
-  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
-  UNUSED_PARAMETER(iOff);
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* If p==0 (unmap the entire file) then there must be no outstanding 
-  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
-  ** then there must be at least one outstanding.  */
-  assert( (p==0)==(pFd->nFetchOut==0) );
-
-  /* If p!=0, it must match the iOff value. */
-  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
-
-  if( p ){
-    pFd->nFetchOut--;
-  }else{
-    unixUnmapfile(pFd);
-  }
-
-  assert( pFd->nFetchOut>=0 );
-#endif
-  return SQLITE_OK;
-}
-
-/*
-** Here ends the implementation of all sqlite3_file methods.
-**
-********************** End sqlite3_file Methods *******************************
-******************************************************************************/
-
-/*
-** This division contains definitions of sqlite3_io_methods objects that
-** implement various file locking strategies.  It also contains definitions
-** of "finder" functions.  A finder-function is used to locate the appropriate
-** sqlite3_io_methods object for a particular database file.  The pAppData
-** field of the sqlite3_vfs VFS objects are initialized to be pointers to
-** the correct finder-function for that VFS.
-**
-** Most finder functions return a pointer to a fixed sqlite3_io_methods
-** object.  The only interesting finder-function is autolockIoFinder, which
-** looks at the filesystem type and tries to guess the best locking
-** strategy from that.
-**
-** For finder-funtion F, two objects are created:
-**
-**    (1) The real finder-function named "FImpt()".
-**
-**    (2) A constant pointer to this function named just "F".
-**
-**
-** A pointer to the F pointer is used as the pAppData value for VFS
-** objects.  We have to do this instead of letting pAppData point
-** directly at the finder-function since C90 rules prevent a void*
-** from be cast into a function pointer.
-**
-**
-** Each instance of this macro generates two objects:
-**
-**   *  A constant sqlite3_io_methods object call METHOD that has locking
-**      methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
-**
-**   *  An I/O method finder function called FINDER that returns a pointer
-**      to the METHOD object in the previous bullet.
-*/
-#define IOMETHODS(FINDER, METHOD, VERSION, CLOSE, LOCK, UNLOCK, CKLOCK)      \
-static const sqlite3_io_methods METHOD = {                                   \
-   VERSION,                    /* iVersion */                                \
-   CLOSE,                      /* xClose */                                  \
-   unixRead,                   /* xRead */                                   \
-   unixWrite,                  /* xWrite */                                  \
-   unixTruncate,               /* xTruncate */                               \
-   unixSync,                   /* xSync */                                   \
-   unixFileSize,               /* xFileSize */                               \
-   LOCK,                       /* xLock */                                   \
-   UNLOCK,                     /* xUnlock */                                 \
-   CKLOCK,                     /* xCheckReservedLock */                      \
-   unixFileControl,            /* xFileControl */                            \
-   unixSectorSize,             /* xSectorSize */                             \
-   unixDeviceCharacteristics,  /* xDeviceCapabilities */                     \
-   unixShmMap,                 /* xShmMap */                                 \
-   unixShmLock,                /* xShmLock */                                \
-   unixShmBarrier,             /* xShmBarrier */                             \
-   unixShmUnmap,               /* xShmUnmap */                               \
-   unixFetch,                  /* xFetch */                                  \
-   unixUnfetch,                /* xUnfetch */                                \
-};                                                                           \
-static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
-  UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
-  return &METHOD;                                                            \
-}                                                                            \
-static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p)    \
-    = FINDER##Impl;
-
-/*
-** Here are all of the sqlite3_io_methods objects for each of the
-** locking strategies.  Functions that return pointers to these methods
-** are also created.
-*/
-IOMETHODS(
-  posixIoFinder,            /* Finder function name */
-  posixIoMethods,           /* sqlite3_io_methods object name */
-  3,                        /* shared memory and mmap are enabled */
-  unixClose,                /* xClose method */
-  unixLock,                 /* xLock method */
-  unixUnlock,               /* xUnlock method */
-  unixCheckReservedLock     /* xCheckReservedLock method */
-)
-IOMETHODS(
-  nolockIoFinder,           /* Finder function name */
-  nolockIoMethods,          /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  nolockClose,              /* xClose method */
-  nolockLock,               /* xLock method */
-  nolockUnlock,             /* xUnlock method */
-  nolockCheckReservedLock   /* xCheckReservedLock method */
-)
-IOMETHODS(
-  dotlockIoFinder,          /* Finder function name */
-  dotlockIoMethods,         /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  dotlockClose,             /* xClose method */
-  dotlockLock,              /* xLock method */
-  dotlockUnlock,            /* xUnlock method */
-  dotlockCheckReservedLock  /* xCheckReservedLock method */
-)
-
-#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
-IOMETHODS(
-  flockIoFinder,            /* Finder function name */
-  flockIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  flockClose,               /* xClose method */
-  flockLock,                /* xLock method */
-  flockUnlock,              /* xUnlock method */
-  flockCheckReservedLock    /* xCheckReservedLock method */
-)
-#endif
-
-#if OS_VXWORKS
-IOMETHODS(
-  semIoFinder,              /* Finder function name */
-  semIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  semClose,                 /* xClose method */
-  semLock,                  /* xLock method */
-  semUnlock,                /* xUnlock method */
-  semCheckReservedLock      /* xCheckReservedLock method */
-)
-#endif
-
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-IOMETHODS(
-  afpIoFinder,              /* Finder function name */
-  afpIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  afpClose,                 /* xClose method */
-  afpLock,                  /* xLock method */
-  afpUnlock,                /* xUnlock method */
-  afpCheckReservedLock      /* xCheckReservedLock method */
-)
-#endif
-
-/*
-** The proxy locking method is a "super-method" in the sense that it
-** opens secondary file descriptors for the conch and lock files and
-** it uses proxy, dot-file, AFP, and flock() locking methods on those
-** secondary files.  For this reason, the division that implements
-** proxy locking is located much further down in the file.  But we need
-** to go ahead and define the sqlite3_io_methods and finder function
-** for proxy locking here.  So we forward declare the I/O methods.
-*/
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-static int proxyClose(sqlite3_file*);
-static int proxyLock(sqlite3_file*, int);
-static int proxyUnlock(sqlite3_file*, int);
-static int proxyCheckReservedLock(sqlite3_file*, int*);
-IOMETHODS(
-  proxyIoFinder,            /* Finder function name */
-  proxyIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* shared memory is disabled */
-  proxyClose,               /* xClose method */
-  proxyLock,                /* xLock method */
-  proxyUnlock,              /* xUnlock method */
-  proxyCheckReservedLock    /* xCheckReservedLock method */
-)
-#endif
-
-/* nfs lockd on OSX 10.3+ doesn't clear write locks when a read lock is set */
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-IOMETHODS(
-  nfsIoFinder,               /* Finder function name */
-  nfsIoMethods,              /* sqlite3_io_methods object name */
-  1,                         /* shared memory is disabled */
-  unixClose,                 /* xClose method */
-  unixLock,                  /* xLock method */
-  nfsUnlock,                 /* xUnlock method */
-  unixCheckReservedLock      /* xCheckReservedLock method */
-)
-#endif
-
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-/* 
-** This "finder" function attempts to determine the best locking strategy 
-** for the database file "filePath".  It then returns the sqlite3_io_methods
-** object that implements that strategy.
-**
-** This is for MacOSX only.
-*/
-static const sqlite3_io_methods *autolockIoFinderImpl(
-  const char *filePath,    /* name of the database file */
-  unixFile *pNew           /* open file object for the database file */
-){
-  static const struct Mapping {
-    const char *zFilesystem;              /* Filesystem type name */
-    const sqlite3_io_methods *pMethods;   /* Appropriate locking method */
-  } aMap[] = {
-    { "hfs",    &posixIoMethods },
-    { "ufs",    &posixIoMethods },
-    { "afpfs",  &afpIoMethods },
-    { "smbfs",  &afpIoMethods },
-    { "webdav", &nolockIoMethods },
-    { 0, 0 }
-  };
-  int i;
-  struct statfs fsInfo;
-  struct flock lockInfo;
-
-  if( !filePath ){
-    /* If filePath==NULL that means we are dealing with a transient file
-    ** that does not need to be locked. */
-    return &nolockIoMethods;
-  }
-  if( statfs(filePath, &fsInfo) != -1 ){
-    if( fsInfo.f_flags & MNT_RDONLY ){
-      return &nolockIoMethods;
-    }
-    for(i=0; aMap[i].zFilesystem; i++){
-      if( strcmp(fsInfo.f_fstypename, aMap[i].zFilesystem)==0 ){
-        return aMap[i].pMethods;
-      }
-    }
-  }
-
-  /* Default case. Handles, amongst others, "nfs".
-  ** Test byte-range lock using fcntl(). If the call succeeds, 
-  ** assume that the file-system supports POSIX style locks. 
-  */
-  lockInfo.l_len = 1;
-  lockInfo.l_start = 0;
-  lockInfo.l_whence = SEEK_SET;
-  lockInfo.l_type = F_RDLCK;
-  if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
-    if( strcmp(fsInfo.f_fstypename, "nfs")==0 ){
-      return &nfsIoMethods;
-    } else {
-      return &posixIoMethods;
-    }
-  }else{
-    return &dotlockIoMethods;
-  }
-}
-static const sqlite3_io_methods 
-  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
-
-#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
-
-#if OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE
-/* 
-** This "finder" function attempts to determine the best locking strategy 
-** for the database file "filePath".  It then returns the sqlite3_io_methods
-** object that implements that strategy.
-**
-** This is for VXWorks only.
-*/
-static const sqlite3_io_methods *autolockIoFinderImpl(
-  const char *filePath,    /* name of the database file */
-  unixFile *pNew           /* the open file object */
-){
-  struct flock lockInfo;
-
-  if( !filePath ){
-    /* If filePath==NULL that means we are dealing with a transient file
-    ** that does not need to be locked. */
-    return &nolockIoMethods;
-  }
-
-  /* Test if fcntl() is supported and use POSIX style locks.
-  ** Otherwise fall back to the named semaphore method.
-  */
-  lockInfo.l_len = 1;
-  lockInfo.l_start = 0;
-  lockInfo.l_whence = SEEK_SET;
-  lockInfo.l_type = F_RDLCK;
-  if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
-    return &posixIoMethods;
-  }else{
-    return &semIoMethods;
-  }
-}
-static const sqlite3_io_methods 
-  *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
-
-#endif /* OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE */
-
-/*
-** An abstract type for a pointer to a IO method finder function:
-*/
-typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
-
-
-/****************************************************************************
-**************************** sqlite3_vfs methods ****************************
-**
-** This division contains the implementation of methods on the
-** sqlite3_vfs object.
-*/
-
-/*
-** Initialize the contents of the unixFile structure pointed to by pId.
-*/
-static int fillInUnixFile(
-  sqlite3_vfs *pVfs,      /* Pointer to vfs object */
-  int h,                  /* Open file descriptor of file being opened */
-  sqlite3_file *pId,      /* Write to the unixFile structure here */
-  const char *zFilename,  /* Name of the file being opened */
-  int ctrlFlags           /* Zero or more UNIXFILE_* values */
-){
-  const sqlite3_io_methods *pLockingStyle;
-  unixFile *pNew = (unixFile *)pId;
-  int rc = SQLITE_OK;
-
-  assert( pNew->pInode==NULL );
-
-  /* Usually the path zFilename should not be a relative pathname. The
-  ** exception is when opening the proxy "conch" file in builds that
-  ** include the special Apple locking styles.
-  */
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-  assert( zFilename==0 || zFilename[0]=='/' 
-    || pVfs->pAppData==(void*)&autolockIoFinder );
-#else
-  assert( zFilename==0 || zFilename[0]=='/' );
-#endif
-
-  /* No locking occurs in temporary files */
-  assert( zFilename!=0 || (ctrlFlags & UNIXFILE_NOLOCK)!=0 );
-
-  OSTRACE(("OPEN    %-3d %s\n", h, zFilename));
-  pNew->h = h;
-  pNew->pVfs = pVfs;
-  pNew->zPath = zFilename;
-  pNew->ctrlFlags = (u8)ctrlFlags;
-#if SQLITE_MAX_MMAP_SIZE>0
-  pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;
-#endif
-  if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
-                           "psow", SQLITE_POWERSAFE_OVERWRITE) ){
-    pNew->ctrlFlags |= UNIXFILE_PSOW;
-  }
-  if( strcmp(pVfs->zName,"unix-excl")==0 ){
-    pNew->ctrlFlags |= UNIXFILE_EXCL;
-  }
-
-#if OS_VXWORKS
-  pNew->pId = vxworksFindFileId(zFilename);
-  if( pNew->pId==0 ){
-    ctrlFlags |= UNIXFILE_NOLOCK;
-    rc = SQLITE_NOMEM;
-  }
-#endif
-
-  if( ctrlFlags & UNIXFILE_NOLOCK ){
-    pLockingStyle = &nolockIoMethods;
-  }else{
-    pLockingStyle = (**(finder_type*)pVfs->pAppData)(zFilename, pNew);
-#if SQLITE_ENABLE_LOCKING_STYLE
-    /* Cache zFilename in the locking context (AFP and dotlock override) for
-    ** proxyLock activation is possible (remote proxy is based on db name)
-    ** zFilename remains valid until file is closed, to support */
-    pNew->lockingContext = (void*)zFilename;
-#endif
-  }
-
-  if( pLockingStyle == &posixIoMethods
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-    || pLockingStyle == &nfsIoMethods
-#endif
-  ){
-    unixEnterMutex();
-    rc = findInodeInfo(pNew, &pNew->pInode);
-    if( rc!=SQLITE_OK ){
-      /* If an error occurred in findInodeInfo(), close the file descriptor
-      ** immediately, before releasing the mutex. findInodeInfo() may fail
-      ** in two scenarios:
-      **
-      **   (a) A call to fstat() failed.
-      **   (b) A malloc failed.
-      **
-      ** Scenario (b) may only occur if the process is holding no other
-      ** file descriptors open on the same file. If there were other file
-      ** descriptors on this file, then no malloc would be required by
-      ** findInodeInfo(). If this is the case, it is quite safe to close
-      ** handle h - as it is guaranteed that no posix locks will be released
-      ** by doing so.
-      **
-      ** If scenario (a) caused the error then things are not so safe. The
-      ** implicit assumption here is that if fstat() fails, things are in
-      ** such bad shape that dropping a lock or two doesn't matter much.
-      */
-      robust_close(pNew, h, __LINE__);
-      h = -1;
-    }
-    unixLeaveMutex();
-  }
-
-#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
-  else if( pLockingStyle == &afpIoMethods ){
-    /* AFP locking uses the file path so it needs to be included in
-    ** the afpLockingContext.
-    */
-    afpLockingContext *pCtx;
-    pNew->lockingContext = pCtx = sqlite3_malloc( sizeof(*pCtx) );
-    if( pCtx==0 ){
-      rc = SQLITE_NOMEM;
-    }else{
-      /* NB: zFilename exists and remains valid until the file is closed
-      ** according to requirement F11141.  So we do not need to make a
-      ** copy of the filename. */
-      pCtx->dbPath = zFilename;
-      pCtx->reserved = 0;
-      srandomdev();
-      unixEnterMutex();
-      rc = findInodeInfo(pNew, &pNew->pInode);
-      if( rc!=SQLITE_OK ){
-        sqlite3_free(pNew->lockingContext);
-        robust_close(pNew, h, __LINE__);
-        h = -1;
-      }
-      unixLeaveMutex();        
-    }
-  }
-#endif
-
-  else if( pLockingStyle == &dotlockIoMethods ){
-    /* Dotfile locking uses the file path so it needs to be included in
-    ** the dotlockLockingContext 
-    */
-    char *zLockFile;
-    int nFilename;
-    assert( zFilename!=0 );
-    nFilename = (int)strlen(zFilename) + 6;
-    zLockFile = (char *)sqlite3_malloc(nFilename);
-    if( zLockFile==0 ){
-      rc = SQLITE_NOMEM;
-    }else{
-      sqlite3_snprintf(nFilename, zLockFile, "%s" DOTLOCK_SUFFIX, zFilename);
-    }
-    pNew->lockingContext = zLockFile;
-  }
-
-#if OS_VXWORKS
-  else if( pLockingStyle == &semIoMethods ){
-    /* Named semaphore locking uses the file path so it needs to be
-    ** included in the semLockingContext
-    */
-    unixEnterMutex();
-    rc = findInodeInfo(pNew, &pNew->pInode);
-    if( (rc==SQLITE_OK) && (pNew->pInode->pSem==NULL) ){
-      char *zSemName = pNew->pInode->aSemName;
-      int n;
-      sqlite3_snprintf(MAX_PATHNAME, zSemName, "/%s.sem",
-                       pNew->pId->zCanonicalName);
-      for( n=1; zSemName[n]; n++ )
-        if( zSemName[n]=='/' ) zSemName[n] = '_';
-      pNew->pInode->pSem = sem_open(zSemName, O_CREAT, 0666, 1);
-      if( pNew->pInode->pSem == SEM_FAILED ){
-        rc = SQLITE_NOMEM;
-        pNew->pInode->aSemName[0] = '\0';
-      }
-    }
-    unixLeaveMutex();
-  }
-#endif
-  
-  pNew->lastErrno = 0;
-#if OS_VXWORKS
-  if( rc!=SQLITE_OK ){
-    if( h>=0 ) robust_close(pNew, h, __LINE__);
-    h = -1;
-    osUnlink(zFilename);
-    pNew->ctrlFlags |= UNIXFILE_DELETE;
-  }
-#endif
-  if( rc!=SQLITE_OK ){
-    if( h>=0 ) robust_close(pNew, h, __LINE__);
-  }else{
-    pNew->pMethod = pLockingStyle;
-    OpenCounter(+1);
-    verifyDbFile(pNew);
-  }
-  return rc;
-}
-
-/*
-** Return the name of a directory in which to put temporary files.
-** If no suitable temporary file directory can be found, return NULL.
-*/
-static const char *unixTempFileDir(void){
-  static const char *azDirs[] = {
-     0,
-     0,
-     0,
-     "/var/tmp",
-     "/usr/tmp",
-     "/tmp",
-     0        /* List terminator */
-  };
-  unsigned int i;
-  struct stat buf;
-  const char *zDir = 0;
-
-  azDirs[0] = sqlite3_temp_directory;
-  if( !azDirs[1] ) azDirs[1] = getenv("SQLITE_TMPDIR");
-  if( !azDirs[2] ) azDirs[2] = getenv("TMPDIR");
-  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
-    if( zDir==0 ) continue;
-    if( osStat(zDir, &buf) ) continue;
-    if( !S_ISDIR(buf.st_mode) ) continue;
-    if( osAccess(zDir, 07) ) continue;
-    break;
-  }
-  return zDir;
-}
-
-/*
-** Create a temporary file name in zBuf.  zBuf must be allocated
-** by the calling process and must be big enough to hold at least
-** pVfs->mxPathname bytes.
-*/
-static int unixGetTempname(int nBuf, char *zBuf){
-  static const unsigned char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  unsigned int i, j;
-  const char *zDir;
-
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. 
-  */
-  SimulateIOError( return SQLITE_IOERR );
-
-  zDir = unixTempFileDir();
-  if( zDir==0 ) zDir = ".";
-
-  /* Check that the output buffer is large enough for the temporary file 
-  ** name. If it is not, return SQLITE_ERROR.
-  */
-  if( (strlen(zDir) + strlen(SQLITE_TEMP_FILE_PREFIX) + 18) >= (size_t)nBuf ){
-    return SQLITE_ERROR;
-  }
-
-  do{
-    sqlite3_snprintf(nBuf-18, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir);
-    j = (int)strlen(zBuf);
-    sqlite3_randomness(15, &zBuf[j]);
-    for(i=0; i<15; i++, j++){
-      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
-    }
-    zBuf[j] = 0;
-    zBuf[j+1] = 0;
-  }while( osAccess(zBuf,0)==0 );
-  return SQLITE_OK;
-}
-
-#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
-/*
-** Routine to transform a unixFile into a proxy-locking unixFile.
-** Implementation in the proxy-lock division, but used by unixOpen()
-** if SQLITE_PREFER_PROXY_LOCKING is defined.
-*/
-static int proxyTransformUnixFile(unixFile*, const char*);
-#endif
-
-/*
-** Search for an unused file descriptor that was opened on the database 
-** file (not a journal or master-journal file) identified by pathname
-** zPath with SQLITE_OPEN_XXX flags matching those passed as the second
-** argument to this function.
-**
-** Such a file descriptor may exist if a database connection was closed
-** but the associated file descriptor could not be closed because some
-** other file descriptor open on the same file is holding a file-lock.
-** Refer to comments in the unixClose() function and the lengthy comment
-** describing "Posix Advisory Locking" at the start of this file for 
-** further details. Also, ticket #4018.
-**
-** If a suitable file descriptor is found, then it is returned. If no
-** such file descriptor is located, -1 is returned.
-*/
-static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
-  UnixUnusedFd *pUnused = 0;
-
-  /* Do not search for an unused file descriptor on vxworks. Not because
-  ** vxworks would not benefit from the change (it might, we're not sure),
-  ** but because no way to test it is currently available. It is better 
-  ** not to risk breaking vxworks support for the sake of such an obscure 
-  ** feature.  */
-#if !OS_VXWORKS
-  struct stat sStat;                   /* Results of stat() call */
-
-  /* A stat() call may fail for various reasons. If this happens, it is
-  ** almost certain that an open() call on the same path will also fail.
-  ** For this reason, if an error occurs in the stat() call here, it is
-  ** ignored and -1 is returned. The caller will try to open a new file
-  ** descriptor on the same path, fail, and return an error to SQLite.
-  **
-  ** Even if a subsequent open() call does succeed, the consequences of
-  ** not searching for a resusable file descriptor are not dire.  */
-  if( 0==osStat(zPath, &sStat) ){
-    unixInodeInfo *pInode;
-
-    unixEnterMutex();
-    pInode = inodeList;
-    while( pInode && (pInode->fileId.dev!=sStat.st_dev
-                     || pInode->fileId.ino!=sStat.st_ino) ){
-       pInode = pInode->pNext;
-    }
-    if( pInode ){
-      UnixUnusedFd **pp;
-      for(pp=&pInode->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
-      pUnused = *pp;
-      if( pUnused ){
-        *pp = pUnused->pNext;
-      }
-    }
-    unixLeaveMutex();
-  }
-#endif    /* if !OS_VXWORKS */
-  return pUnused;
-}
-
-/*
-** This function is called by unixOpen() to determine the unix permissions
-** to create new files with. If no error occurs, then SQLITE_OK is returned
-** and a value suitable for passing as the third argument to open(2) is
-** written to *pMode. If an IO error occurs, an SQLite error code is 
-** returned and the value of *pMode is not modified.
-**
-** In most cases cases, this routine sets *pMode to 0, which will become
-** an indication to robust_open() to create the file using
-** SQLITE_DEFAULT_FILE_PERMISSIONS adjusted by the umask.
-** But if the file being opened is a WAL or regular journal file, then 
-** this function queries the file-system for the permissions on the 
-** corresponding database file and sets *pMode to this value. Whenever 
-** possible, WAL and journal files are created using the same permissions 
-** as the associated database file.
-**
-** If the SQLITE_ENABLE_8_3_NAMES option is enabled, then the
-** original filename is unavailable.  But 8_3_NAMES is only used for
-** FAT filesystems and permissions do not matter there, so just use
-** the default permissions.
-*/
-static int findCreateFileMode(
-  const char *zPath,              /* Path of file (possibly) being created */
-  int flags,                      /* Flags passed as 4th argument to xOpen() */
-  mode_t *pMode,                  /* OUT: Permissions to open file with */
-  uid_t *pUid,                    /* OUT: uid to set on the file */
-  gid_t *pGid                     /* OUT: gid to set on the file */
-){
-  int rc = SQLITE_OK;             /* Return Code */
-  *pMode = 0;
-  *pUid = 0;
-  *pGid = 0;
-  if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
-    char zDb[MAX_PATHNAME+1];     /* Database file path */
-    int nDb;                      /* Number of valid bytes in zDb */
-    struct stat sStat;            /* Output of stat() on database file */
-
-    /* zPath is a path to a WAL or journal file. The following block derives
-    ** the path to the associated database file from zPath. This block handles
-    ** the following naming conventions:
-    **
-    **   "<path to db>-journal"
-    **   "<path to db>-wal"
-    **   "<path to db>-journalNN"
-    **   "<path to db>-walNN"
-    **
-    ** where NN is a decimal number. The NN naming schemes are 
-    ** used by the test_multiplex.c module.
-    */
-    nDb = sqlite3Strlen30(zPath) - 1; 
-#ifdef SQLITE_ENABLE_8_3_NAMES
-    while( nDb>0 && sqlite3Isalnum(zPath[nDb]) ) nDb--;
-    if( nDb==0 || zPath[nDb]!='-' ) return SQLITE_OK;
-#else
-    while( zPath[nDb]!='-' ){
-      assert( nDb>0 );
-      assert( zPath[nDb]!='\n' );
-      nDb--;
-    }
-#endif
-    memcpy(zDb, zPath, nDb);
-    zDb[nDb] = '\0';
-
-    if( 0==osStat(zDb, &sStat) ){
-      *pMode = sStat.st_mode & 0777;
-      *pUid = sStat.st_uid;
-      *pGid = sStat.st_gid;
-    }else{
-      rc = SQLITE_IOERR_FSTAT;
-    }
-  }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
-    *pMode = 0600;
-  }
-  return rc;
-}
-
-/*
-** Open the file zPath.
-** 
-** Previously, the SQLite OS layer used three functions in place of this
-** one:
-**
-**     sqlite3OsOpenReadWrite();
-**     sqlite3OsOpenReadOnly();
-**     sqlite3OsOpenExclusive();
-**
-** These calls correspond to the following combinations of flags:
-**
-**     ReadWrite() ->     (READWRITE | CREATE)
-**     ReadOnly()  ->     (READONLY) 
-**     OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE)
-**
-** The old OpenExclusive() accepted a boolean argument - "delFlag". If
-** true, the file was configured to be automatically deleted when the
-** file handle closed. To achieve the same effect using this new 
-** interface, add the DELETEONCLOSE flag to those specified above for 
-** OpenExclusive().
-*/
-static int unixOpen(
-  sqlite3_vfs *pVfs,           /* The VFS for which this is the xOpen method */
-  const char *zPath,           /* Pathname of file to be opened */
-  sqlite3_file *pFile,         /* The file descriptor to be filled in */
-  int flags,                   /* Input flags to control the opening */
-  int *pOutFlags               /* Output flags returned to SQLite core */
-){
-  unixFile *p = (unixFile *)pFile;
-  int fd = -1;                   /* File descriptor returned by open() */
-  int openFlags = 0;             /* Flags to pass to open() */
-  int eType = flags&0xFFFFFF00;  /* Type of file to open */
-  int noLock;                    /* True to omit locking primitives */
-  int rc = SQLITE_OK;            /* Function Return Code */
-  int ctrlFlags = 0;             /* UNIXFILE_* flags */
-
-  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
-  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
-  int isCreate     = (flags & SQLITE_OPEN_CREATE);
-  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
-  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
-#if SQLITE_ENABLE_LOCKING_STYLE
-  int isAutoProxy  = (flags & SQLITE_OPEN_AUTOPROXY);
-#endif
-#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
-  struct statfs fsInfo;
-#endif
-
-  /* If creating a master or main-file journal, this function will open
-  ** a file-descriptor on the directory too. The first time unixSync()
-  ** is called the directory file descriptor will be fsync()ed and close()d.
-  */
-  int syncDir = (isCreate && (
-        eType==SQLITE_OPEN_MASTER_JOURNAL 
-     || eType==SQLITE_OPEN_MAIN_JOURNAL 
-     || eType==SQLITE_OPEN_WAL
-  ));
-
-  /* If argument zPath is a NULL pointer, this function is required to open
-  ** a temporary file. Use this buffer to store the file name in.
-  */
-  char zTmpname[MAX_PATHNAME+2];
-  const char *zName = zPath;
-
-  /* Check the following statements are true: 
-  **
-  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
-  **   (b) if CREATE is set, then READWRITE must also be set, and
-  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
-  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
-  */
-  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
-  assert(isCreate==0 || isReadWrite);
-  assert(isExclusive==0 || isCreate);
-  assert(isDelete==0 || isCreate);
-
-  /* The main DB, main journal, WAL file and master journal are never 
-  ** automatically deleted. Nor are they ever temporary files.  */
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
-
-  /* Assert that the upper layer has set one of the "file-type" flags. */
-  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
-       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
-       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
-  );
-
-  memset(p, 0, sizeof(unixFile));
-
-  if( eType==SQLITE_OPEN_MAIN_DB ){
-    UnixUnusedFd *pUnused;
-    pUnused = findReusableFd(zName, flags);
-    if( pUnused ){
-      fd = pUnused->fd;
-    }else{
-      pUnused = sqlite3_malloc(sizeof(*pUnused));
-      if( !pUnused ){
-        return SQLITE_NOMEM;
-      }
-    }
-    p->pUnused = pUnused;
-
-    /* Database filenames are double-zero terminated if they are not
-    ** URIs with parameters.  Hence, they can always be passed into
-    ** sqlite3_uri_parameter(). */
-    assert( (flags & SQLITE_OPEN_URI) || zName[strlen(zName)+1]==0 );
-
-  }else if( !zName ){
-    /* If zName is NULL, the upper layer is requesting a temp file. */
-    assert(isDelete && !syncDir);
-    rc = unixGetTempname(MAX_PATHNAME+2, zTmpname);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    zName = zTmpname;
-
-    /* Generated temporary filenames are always double-zero terminated
-    ** for use by sqlite3_uri_parameter(). */
-    assert( zName[strlen(zName)+1]==0 );
-  }
-
-  /* Determine the value of the flags parameter passed to POSIX function
-  ** open(). These must be calculated even if open() is not called, as
-  ** they may be stored as part of the file handle and used by the 
-  ** 'conch file' locking functions later on.  */
-  if( isReadonly )  openFlags |= O_RDONLY;
-  if( isReadWrite ) openFlags |= O_RDWR;
-  if( isCreate )    openFlags |= O_CREAT;
-  if( isExclusive ) openFlags |= (O_EXCL|O_NOFOLLOW);
-  openFlags |= (O_LARGEFILE|O_BINARY);
-
-  if( fd<0 ){
-    mode_t openMode;              /* Permissions to create file with */
-    uid_t uid;                    /* Userid for the file */
-    gid_t gid;                    /* Groupid for the file */
-    rc = findCreateFileMode(zName, flags, &openMode, &uid, &gid);
-    if( rc!=SQLITE_OK ){
-      assert( !p->pUnused );
-      assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
-      return rc;
-    }
-    fd = robust_open(zName, openFlags, openMode);
-    OSTRACE(("OPENX   %-3d %s 0%o\n", fd, zName, openFlags));
-    if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
-      /* Failed to open the file for read/write access. Try read-only. */
-      flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
-      openFlags &= ~(O_RDWR|O_CREAT);
-      flags |= SQLITE_OPEN_READONLY;
-      openFlags |= O_RDONLY;
-      isReadonly = 1;
-      fd = robust_open(zName, openFlags, openMode);
-    }
-    if( fd<0 ){
-      rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zName);
-      goto open_finished;
-    }
-
-    /* If this process is running as root and if creating a new rollback
-    ** journal or WAL file, set the ownership of the journal or WAL to be
-    ** the same as the original database.
-    */
-    if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
-      osFchown(fd, uid, gid);
-    }
-  }
-  assert( fd>=0 );
-  if( pOutFlags ){
-    *pOutFlags = flags;
-  }
-
-  if( p->pUnused ){
-    p->pUnused->fd = fd;
-    p->pUnused->flags = flags;
-  }
-
-  if( isDelete ){
-#if OS_VXWORKS
-    zPath = zName;
-#else
-    osUnlink(zName);
-#endif
-  }
-#if SQLITE_ENABLE_LOCKING_STYLE
-  else{
-    p->openFlags = openFlags;
-  }
-#endif
-
-  noLock = eType!=SQLITE_OPEN_MAIN_DB;
-
-  
-#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
-  if( fstatfs(fd, &fsInfo) == -1 ){
-    ((unixFile*)pFile)->lastErrno = errno;
-    robust_close(p, fd, __LINE__);
-    return SQLITE_IOERR_ACCESS;
-  }
-  if (0 == strncmp("msdos", fsInfo.f_fstypename, 5)) {
-    ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
-  }
-#endif
-
-  /* Set up appropriate ctrlFlags */
-  if( isDelete )                ctrlFlags |= UNIXFILE_DELETE;
-  if( isReadonly )              ctrlFlags |= UNIXFILE_RDONLY;
-  if( noLock )                  ctrlFlags |= UNIXFILE_NOLOCK;
-  if( syncDir )                 ctrlFlags |= UNIXFILE_DIRSYNC;
-  if( flags & SQLITE_OPEN_URI ) ctrlFlags |= UNIXFILE_URI;
-
-#if SQLITE_ENABLE_LOCKING_STYLE
-#if SQLITE_PREFER_PROXY_LOCKING
-  isAutoProxy = 1;
-#endif
-  if( isAutoProxy && (zPath!=NULL) && (!noLock) && pVfs->xOpen ){
-    char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
-    int useProxy = 0;
-
-    /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means 
-    ** never use proxy, NULL means use proxy for non-local files only.  */
-    if( envforce!=NULL ){
-      useProxy = atoi(envforce)>0;
-    }else{
-      if( statfs(zPath, &fsInfo) == -1 ){
-        /* In theory, the close(fd) call is sub-optimal. If the file opened
-        ** with fd is a database file, and there are other connections open
-        ** on that file that are currently holding advisory locks on it,
-        ** then the call to close() will cancel those locks. In practice,
-        ** we're assuming that statfs() doesn't fail very often. At least
-        ** not while other file descriptors opened by the same process on
-        ** the same file are working.  */
-        p->lastErrno = errno;
-        robust_close(p, fd, __LINE__);
-        rc = SQLITE_IOERR_ACCESS;
-        goto open_finished;
-      }
-      useProxy = !(fsInfo.f_flags&MNT_LOCAL);
-    }
-    if( useProxy ){
-      rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
-      if( rc==SQLITE_OK ){
-        rc = proxyTransformUnixFile((unixFile*)pFile, ":auto:");
-        if( rc!=SQLITE_OK ){
-          /* Use unixClose to clean up the resources added in fillInUnixFile 
-          ** and clear all the structure's references.  Specifically, 
-          ** pFile->pMethods will be NULL so sqlite3OsClose will be a no-op 
-          */
-          unixClose(pFile);
-          return rc;
-        }
-      }
-      goto open_finished;
-    }
-  }
-#endif
-  
-  rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
-
-open_finished:
-  if( rc!=SQLITE_OK ){
-    sqlite3_free(p->pUnused);
-  }
-  return rc;
-}
-
-
-/*
-** Delete the file at zPath. If the dirSync argument is true, fsync()
-** the directory after deleting the file.
-*/
-static int unixDelete(
-  sqlite3_vfs *NotUsed,     /* VFS containing this as the xDelete method */
-  const char *zPath,        /* Name of file to be deleted */
-  int dirSync               /* If true, fsync() directory after deleting file */
-){
-  int rc = SQLITE_OK;
-  UNUSED_PARAMETER(NotUsed);
-  SimulateIOError(return SQLITE_IOERR_DELETE);
-  if( osUnlink(zPath)==(-1) ){
-    if( errno==ENOENT ){
-      rc = SQLITE_IOERR_DELETE_NOENT;
-    }else{
-      rc = unixLogError(SQLITE_IOERR_DELETE, "unlink", zPath);
-    }
-    return rc;
-  }
-#ifndef SQLITE_DISABLE_DIRSYNC
-  if( (dirSync & 1)!=0 ){
-    int fd;
-    rc = osOpenDirectory(zPath, &fd);
-    if( rc==SQLITE_OK ){
-#if OS_VXWORKS
-      if( fsync(fd)==-1 )
-#else
-      if( fsync(fd) )
-#endif
-      {
-        rc = unixLogError(SQLITE_IOERR_DIR_FSYNC, "fsync", zPath);
-      }
-      robust_close(0, fd, __LINE__);
-    }else if( rc==SQLITE_CANTOPEN ){
-      rc = SQLITE_OK;
-    }
-  }
-#endif
-  return rc;
-}
-
-/*
-** Test the existence of or access permissions of file zPath. The
-** test performed depends on the value of flags:
-**
-**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
-**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
-**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
-**
-** Otherwise return 0.
-*/
-static int unixAccess(
-  sqlite3_vfs *NotUsed,   /* The VFS containing this xAccess method */
-  const char *zPath,      /* Path of the file to examine */
-  int flags,              /* What do we want to learn about the zPath file? */
-  int *pResOut            /* Write result boolean here */
-){
-  int amode = 0;
-  UNUSED_PARAMETER(NotUsed);
-  SimulateIOError( return SQLITE_IOERR_ACCESS; );
-  switch( flags ){
-    case SQLITE_ACCESS_EXISTS:
-      amode = F_OK;
-      break;
-    case SQLITE_ACCESS_READWRITE:
-      amode = W_OK|R_OK;
-      break;
-    case SQLITE_ACCESS_READ:
-      amode = R_OK;
-      break;
-
-    default:
-      assert(!"Invalid flags argument");
-  }
-  *pResOut = (osAccess(zPath, amode)==0);
-  if( flags==SQLITE_ACCESS_EXISTS && *pResOut ){
-    struct stat buf;
-    if( 0==osStat(zPath, &buf) && buf.st_size==0 ){
-      *pResOut = 0;
-    }
-  }
-  return SQLITE_OK;
-}
-
-
-/*
-** Turn a relative pathname into a full pathname. The relative path
-** is stored as a nul-terminated string in the buffer pointed to by
-** zPath. 
-**
-** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
-** (in this case, MAX_PATHNAME bytes). The full-path is written to
-** this buffer before returning.
-*/
-static int unixFullPathname(
-  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
-  const char *zPath,            /* Possibly relative input path */
-  int nOut,                     /* Size of output buffer in bytes */
-  char *zOut                    /* Output buffer */
-){
-
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. This function could fail if, for example, the
-  ** current working directory has been unlinked.
-  */
-  SimulateIOError( return SQLITE_ERROR );
-
-  assert( pVfs->mxPathname==MAX_PATHNAME );
-  UNUSED_PARAMETER(pVfs);
-
-  zOut[nOut-1] = '\0';
-  if( zPath[0]=='/' ){
-    sqlite3_snprintf(nOut, zOut, "%s", zPath);
-  }else{
-    int nCwd;
-    if( osGetcwd(zOut, nOut-1)==0 ){
-      return unixLogError(SQLITE_CANTOPEN_BKPT, "getcwd", zPath);
-    }
-    nCwd = (int)strlen(zOut);
-    sqlite3_snprintf(nOut-nCwd, &zOut[nCwd], "/%s", zPath);
-  }
-  return SQLITE_OK;
-}
-
-
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
-/*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
-*/
-#include <dlfcn.h>
-static void *unixDlOpen(sqlite3_vfs *NotUsed, const char *zFilename){
-  UNUSED_PARAMETER(NotUsed);
-  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
-}
-
-/*
-** SQLite calls this function immediately after a call to unixDlSym() or
-** unixDlOpen() fails (returns a null pointer). If a more detailed error
-** message is available, it is written to zBufOut. If no error message
-** is available, zBufOut is left unmodified and SQLite uses a default
-** error message.
-*/
-static void unixDlError(sqlite3_vfs *NotUsed, int nBuf, char *zBufOut){
-  const char *zErr;
-  UNUSED_PARAMETER(NotUsed);
-  unixEnterMutex();
-  zErr = dlerror();
-  if( zErr ){
-    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
-  }
-  unixLeaveMutex();
-}
-static void (*unixDlSym(sqlite3_vfs *NotUsed, void *p, const char*zSym))(void){
-  /* 
-  ** GCC with -pedantic-errors says that C90 does not allow a void* to be
-  ** cast into a pointer to a function.  And yet the library dlsym() routine
-  ** returns a void* which is really a pointer to a function.  So how do we
-  ** use dlsym() with -pedantic-errors?
-  **
-  ** Variable x below is defined to be a pointer to a function taking
-  ** parameters void* and const char* and returning a pointer to a function.
-  ** We initialize x by assigning it a pointer to the dlsym() function.
-  ** (That assignment requires a cast.)  Then we call the function that
-  ** x points to.  
-  **
-  ** This work-around is unlikely to work correctly on any system where
-  ** you really cannot cast a function pointer into void*.  But then, on the
-  ** other hand, dlsym() will not work on such a system either, so we have
-  ** not really lost anything.
-  */
-  void (*(*x)(void*,const char*))(void);
-  UNUSED_PARAMETER(NotUsed);
-  x = (void(*(*)(void*,const char*))(void))dlsym;
-  return (*x)(p, zSym);
-}
-static void unixDlClose(sqlite3_vfs *NotUsed, void *pHandle){
-  UNUSED_PARAMETER(NotUsed);
-  dlclose(pHandle);
-}
-#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
-  #define unixDlOpen  0
-  #define unixDlError 0
-  #define unixDlSym   0
-  #define unixDlClose 0
-#endif
-
-/*
-** Write nBuf bytes of random data to the supplied buffer zBuf.
-*/
-static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
-  UNUSED_PARAMETER(NotUsed);
-  assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));
-
-  /* We have to initialize zBuf to prevent valgrind from reporting
-  ** errors.  The reports issued by valgrind are incorrect - we would
-  ** prefer that the randomness be increased by making use of the
-  ** uninitialized space in zBuf - but valgrind errors tend to worry
-  ** some users.  Rather than argue, it seems easier just to initialize
-  ** the whole array and silence valgrind, even if that means less randomness
-  ** in the random seed.
-  **
-  ** When testing, initializing zBuf[] to zero is all we do.  That means
-  ** that we always use the same random number sequence.  This makes the
-  ** tests repeatable.
-  */
-  memset(zBuf, 0, nBuf);
-#if !defined(SQLITE_TEST)
-  {
-    int pid, fd, got;
-    fd = robust_open("/dev/urandom", O_RDONLY, 0);
-    if( fd<0 ){
-      time_t t;
-      time(&t);
-      memcpy(zBuf, &t, sizeof(t));
-      pid = getpid();
-      memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid));
-      assert( sizeof(t)+sizeof(pid)<=(size_t)nBuf );
-      nBuf = sizeof(t) + sizeof(pid);
-    }else{
-      do{ got = osRead(fd, zBuf, nBuf); }while( got<0 && errno==EINTR );
-      robust_close(0, fd, __LINE__);
-    }
-  }
-#endif
-  return nBuf;
-}
-
-
-/*
-** Sleep for a little while.  Return the amount of time slept.
-** The argument is the number of microseconds we want to sleep.
-** The return value is the number of microseconds of sleep actually
-** requested from the underlying operating system, a number which
-** might be greater than or equal to the argument, but not less
-** than the argument.
-*/
-static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
-#if OS_VXWORKS
-  struct timespec sp;
-
-  sp.tv_sec = microseconds / 1000000;
-  sp.tv_nsec = (microseconds % 1000000) * 1000;
-  nanosleep(&sp, NULL);
-  UNUSED_PARAMETER(NotUsed);
-  return microseconds;
-#elif defined(HAVE_USLEEP) && HAVE_USLEEP
-  usleep(microseconds);
-  UNUSED_PARAMETER(NotUsed);
-  return microseconds;
-#else
-  int seconds = (microseconds+999999)/1000000;
-  sleep(seconds);
-  UNUSED_PARAMETER(NotUsed);
-  return seconds*1000000;
-#endif
-}
-
-/*
-** The following variable, if set to a non-zero value, is interpreted as
-** the number of seconds since 1970 and is used to set the result of
-** sqlite3OsCurrentTime() during testing.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
-#endif
-
-/*
-** Find the current time (in Universal Coordinated Time).  Write into *piNow
-** the current time and date as a Julian Day number times 86_400_000.  In
-** other words, write into *piNow the number of milliseconds since the Julian
-** epoch of noon in Greenwich on November 24, 4714 B.C according to the
-** proleptic Gregorian calendar.
-**
-** On success, return SQLITE_OK.  Return SQLITE_ERROR if the time and date 
-** cannot be found.
-*/
-static int unixCurrentTimeInt64(sqlite3_vfs *NotUsed, sqlite3_int64 *piNow){
-  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
-  int rc = SQLITE_OK;
-#if defined(NO_GETTOD)
-  time_t t;
-  time(&t);
-  *piNow = ((sqlite3_int64)t)*1000 + unixEpoch;
-#elif OS_VXWORKS
-  struct timespec sNow;
-  clock_gettime(CLOCK_REALTIME, &sNow);
-  *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_nsec/1000000;
-#else
-  struct timeval sNow;
-  if( gettimeofday(&sNow, 0)==0 ){
-    *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;
-  }else{
-    rc = SQLITE_ERROR;
-  }
-#endif
-
-#ifdef SQLITE_TEST
-  if( sqlite3_current_time ){
-    *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
-  }
-#endif
-  UNUSED_PARAMETER(NotUsed);
-  return rc;
-}
-
-/*
-** Find the current time (in Universal Coordinated Time).  Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0.  Return 1 if the time and date cannot be found.
-*/
-static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
-  sqlite3_int64 i = 0;
-  int rc;
-  UNUSED_PARAMETER(NotUsed);
-  rc = unixCurrentTimeInt64(0, &i);
-  *prNow = i/86400000.0;
-  return rc;
-}
-
-/*
-** We added the xGetLastError() method with the intention of providing
-** better low-level error messages when operating-system problems come up
-** during SQLite operation.  But so far, none of that has been implemented
-** in the core.  So this routine is never called.  For now, it is merely
-** a place-holder.
-*/
-static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
-  UNUSED_PARAMETER(NotUsed);
-  UNUSED_PARAMETER(NotUsed2);
-  UNUSED_PARAMETER(NotUsed3);
-  return 0;
-}
-
-
-/*
-************************ End of sqlite3_vfs methods ***************************
-******************************************************************************/
-
-/******************************************************************************
-************************** Begin Proxy Locking ********************************
-**
-** Proxy locking is a "uber-locking-method" in this sense:  It uses the
-** other locking methods on secondary lock files.  Proxy locking is a
-** meta-layer over top of the primitive locking implemented above.  For
-** this reason, the division that implements of proxy locking is deferred
-** until late in the file (here) after all of the other I/O methods have
-** been defined - so that the primitive locking methods are available
-** as services to help with the implementation of proxy locking.
-**
-****
-**
-** The default locking schemes in SQLite use byte-range locks on the
-** database file to coordinate safe, concurrent access by multiple readers
-** and writers [http://sqlite.org/lockingv3.html].  The five file locking
-** states (UNLOCKED, PENDING, SHARED, RESERVED, EXCLUSIVE) are implemented
-** as POSIX read & write locks over fixed set of locations (via fsctl),
-** on AFP and SMB only exclusive byte-range locks are available via fsctl
-** with _IOWR('z', 23, struct ByteRangeLockPB2) to track the same 5 states.
-** To simulate a F_RDLCK on the shared range, on AFP a randomly selected
-** address in the shared range is taken for a SHARED lock, the entire
-** shared range is taken for an EXCLUSIVE lock):
-**
-**      PENDING_BYTE        0x40000000
-**      RESERVED_BYTE       0x40000001
-**      SHARED_RANGE        0x40000002 -> 0x40000200
-**
-** This works well on the local file system, but shows a nearly 100x
-** slowdown in read performance on AFP because the AFP client disables
-** the read cache when byte-range locks are present.  Enabling the read
-** cache exposes a cache coherency problem that is present on all OS X
-** supported network file systems.  NFS and AFP both observe the
-** close-to-open semantics for ensuring cache coherency
-** [http://nfs.sourceforge.net/#faq_a8], which does not effectively
-** address the requirements for concurrent database access by multiple
-** readers and writers
-** [http://www.nabble.com/SQLite-on-NFS-cache-coherency-td15655701.html].
-**
-** To address the performance and cache coherency issues, proxy file locking
-** changes the way database access is controlled by limiting access to a
-** single host at a time and moving file locks off of the database file
-** and onto a proxy file on the local file system.  
-**
-**
-** Using proxy locks
-** -----------------
-**
-** C APIs
-**
-**  sqlite3_file_control(db, dbname, SQLITE_SET_LOCKPROXYFILE,
-**                       <proxy_path> | ":auto:");
-**  sqlite3_file_control(db, dbname, SQLITE_GET_LOCKPROXYFILE, &<proxy_path>);
-**
-**
-** SQL pragmas
-**
-**  PRAGMA [database.]lock_proxy_file=<proxy_path> | :auto:
-**  PRAGMA [database.]lock_proxy_file
-**
-** Specifying ":auto:" means that if there is a conch file with a matching
-** host ID in it, the proxy path in the conch file will be used, otherwise
-** a proxy path based on the user's temp dir
-** (via confstr(_CS_DARWIN_USER_TEMP_DIR,...)) will be used and the
-** actual proxy file name is generated from the name and path of the
-** database file.  For example:
-**
-**       For database path "/Users/me/foo.db" 
-**       The lock path will be "<tmpdir>/sqliteplocks/_Users_me_foo.db:auto:")
-**
-** Once a lock proxy is configured for a database connection, it can not
-** be removed, however it may be switched to a different proxy path via
-** the above APIs (assuming the conch file is not being held by another
-** connection or process). 
-**
-**
-** How proxy locking works
-** -----------------------
-**
-** Proxy file locking relies primarily on two new supporting files: 
-**
-**   *  conch file to limit access to the database file to a single host
-**      at a time
-**
-**   *  proxy file to act as a proxy for the advisory locks normally
-**      taken on the database
-**
-** The conch file - to use a proxy file, sqlite must first "hold the conch"
-** by taking an sqlite-style shared lock on the conch file, reading the
-** contents and comparing the host's unique host ID (see below) and lock
-** proxy path against the values stored in the conch.  The conch file is
-** stored in the same directory as the database file and the file name
-** is patterned after the database file name as ".<databasename>-conch".
-** If the conch file does not exist, or it's contents do not match the
-** host ID and/or proxy path, then the lock is escalated to an exclusive
-** lock and the conch file contents is updated with the host ID and proxy
-** path and the lock is downgraded to a shared lock again.  If the conch
-** is held by another process (with a shared lock), the exclusive lock
-** will fail and SQLITE_BUSY is returned.
-**
-** The proxy file - a single-byte file used for all advisory file locks
-** normally taken on the database file.   This allows for safe sharing
-** of the database file for multiple readers and writers on the same
-** host (the conch ensures that they all use the same local lock file).
-**
-** Requesting the lock proxy does not immediately take the conch, it is
-** only taken when the first request to lock database file is made.  
-** This matches the semantics of the traditional locking behavior, where
-** opening a connection to a database file does not take a lock on it.
-** The shared lock and an open file descriptor are maintained until 
-** the connection to the database is closed. 
-**
-** The proxy file and the lock file are never deleted so they only need
-** to be created the first time they are used.
-**
-** Configuration options
-** ---------------------
-**
-**  SQLITE_PREFER_PROXY_LOCKING
-**
-**       Database files accessed on non-local file systems are
-**       automatically configured for proxy locking, lock files are
-**       named automatically using the same logic as
-**       PRAGMA lock_proxy_file=":auto:"
-**    
-**  SQLITE_PROXY_DEBUG
-**
-**       Enables the logging of error messages during host id file
-**       retrieval and creation
-**
-**  LOCKPROXYDIR
-**
-**       Overrides the default directory used for lock proxy files that
-**       are named automatically via the ":auto:" setting
-**
-**  SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
-**
-**       Permissions to use when creating a directory for storing the
-**       lock proxy files, only used when LOCKPROXYDIR is not set.
-**    
-**    
-** As mentioned above, when compiled with SQLITE_PREFER_PROXY_LOCKING,
-** setting the environment variable SQLITE_FORCE_PROXY_LOCKING to 1 will
-** force proxy locking to be used for every database file opened, and 0
-** will force automatic proxy locking to be disabled for all database
-** files (explicity calling the SQLITE_SET_LOCKPROXYFILE pragma or
-** sqlite_file_control API is not affected by SQLITE_FORCE_PROXY_LOCKING).
-*/
-
-/*
-** Proxy locking is only available on MacOSX 
-*/
-#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
-
-/*
-** The proxyLockingContext has the path and file structures for the remote 
-** and local proxy files in it
-*/
-typedef struct proxyLockingContext proxyLockingContext;
-struct proxyLockingContext {
-  unixFile *conchFile;         /* Open conch file */
-  char *conchFilePath;         /* Name of the conch file */
-  unixFile *lockProxy;         /* Open proxy lock file */
-  char *lockProxyPath;         /* Name of the proxy lock file */
-  char *dbPath;                /* Name of the open file */
-  int conchHeld;               /* 1 if the conch is held, -1 if lockless */
-  void *oldLockingContext;     /* Original lockingcontext to restore on close */
-  sqlite3_io_methods const *pOldMethod;     /* Original I/O methods for close */
-};
-
-/* 
-** The proxy lock file path for the database at dbPath is written into lPath, 
-** which must point to valid, writable memory large enough for a maxLen length
-** file path. 
-*/
-static int proxyGetLockPath(const char *dbPath, char *lPath, size_t maxLen){
-  int len;
-  int dbLen;
-  int i;
-
-#ifdef LOCKPROXYDIR
-  len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
-#else
-# ifdef _CS_DARWIN_USER_TEMP_DIR
-  {
-    if( !confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen) ){
-      OSTRACE(("GETLOCKPATH  failed %s errno=%d pid=%d\n",
-               lPath, errno, getpid()));
-      return SQLITE_IOERR_LOCK;
-    }
-    len = strlcat(lPath, "sqliteplocks", maxLen);    
-  }
-# else
-  len = strlcpy(lPath, "/tmp/", maxLen);
-# endif
-#endif
-
-  if( lPath[len-1]!='/' ){
-    len = strlcat(lPath, "/", maxLen);
-  }
-  
-  /* transform the db path to a unique cache name */
-  dbLen = (int)strlen(dbPath);
-  for( i=0; i<dbLen && (i+len+7)<(int)maxLen; i++){
-    char c = dbPath[i];
-    lPath[i+len] = (c=='/')?'_':c;
-  }
-  lPath[i+len]='\0';
-  strlcat(lPath, ":auto:", maxLen);
-  OSTRACE(("GETLOCKPATH  proxy lock path=%s pid=%d\n", lPath, getpid()));
-  return SQLITE_OK;
-}
-
-/* 
- ** Creates the lock file and any missing directories in lockPath
- */
-static int proxyCreateLockPath(const char *lockPath){
-  int i, len;
-  char buf[MAXPATHLEN];
-  int start = 0;
-  
-  assert(lockPath!=NULL);
-  /* try to create all the intermediate directories */
-  len = (int)strlen(lockPath);
-  buf[0] = lockPath[0];
-  for( i=1; i<len; i++ ){
-    if( lockPath[i] == '/' && (i - start > 0) ){
-      /* only mkdir if leaf dir != "." or "/" or ".." */
-      if( i-start>2 || (i-start==1 && buf[start] != '.' && buf[start] != '/') 
-         || (i-start==2 && buf[start] != '.' && buf[start+1] != '.') ){
-        buf[i]='\0';
-        if( osMkdir(buf, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
-          int err=errno;
-          if( err!=EEXIST ) {
-            OSTRACE(("CREATELOCKPATH  FAILED creating %s, "
-                     "'%s' proxy lock path=%s pid=%d\n",
-                     buf, strerror(err), lockPath, getpid()));
-            return err;
-          }
-        }
-      }
-      start=i+1;
-    }
-    buf[i] = lockPath[i];
-  }
-  OSTRACE(("CREATELOCKPATH  proxy lock path=%s pid=%d\n", lockPath, getpid()));
-  return 0;
-}
-
-/*
-** Create a new VFS file descriptor (stored in memory obtained from
-** sqlite3_malloc) and open the file named "path" in the file descriptor.
-**
-** The caller is responsible not only for closing the file descriptor
-** but also for freeing the memory associated with the file descriptor.
-*/
-static int proxyCreateUnixFile(
-    const char *path,        /* path for the new unixFile */
-    unixFile **ppFile,       /* unixFile created and returned by ref */
-    int islockfile           /* if non zero missing dirs will be created */
-) {
-  int fd = -1;
-  unixFile *pNew;
-  int rc = SQLITE_OK;
-  int openFlags = O_RDWR | O_CREAT;
-  sqlite3_vfs dummyVfs;
-  int terrno = 0;
-  UnixUnusedFd *pUnused = NULL;
-
-  /* 1. first try to open/create the file
-  ** 2. if that fails, and this is a lock file (not-conch), try creating
-  ** the parent directories and then try again.
-  ** 3. if that fails, try to open the file read-only
-  ** otherwise return BUSY (if lock file) or CANTOPEN for the conch file
-  */
-  pUnused = findReusableFd(path, openFlags);
-  if( pUnused ){
-    fd = pUnused->fd;
-  }else{
-    pUnused = sqlite3_malloc(sizeof(*pUnused));
-    if( !pUnused ){
-      return SQLITE_NOMEM;
-    }
-  }
-  if( fd<0 ){
-    fd = robust_open(path, openFlags, 0);
-    terrno = errno;
-    if( fd<0 && errno==ENOENT && islockfile ){
-      if( proxyCreateLockPath(path) == SQLITE_OK ){
-        fd = robust_open(path, openFlags, 0);
-      }
-    }
-  }
-  if( fd<0 ){
-    openFlags = O_RDONLY;
-    fd = robust_open(path, openFlags, 0);
-    terrno = errno;
-  }
-  if( fd<0 ){
-    if( islockfile ){
-      return SQLITE_BUSY;
-    }
-    switch (terrno) {
-      case EACCES:
-        return SQLITE_PERM;
-      case EIO: 
-        return SQLITE_IOERR_LOCK; /* even though it is the conch */
-      default:
-        return SQLITE_CANTOPEN_BKPT;
-    }
-  }
-  
-  pNew = (unixFile *)sqlite3_malloc(sizeof(*pNew));
-  if( pNew==NULL ){
-    rc = SQLITE_NOMEM;
-    goto end_create_proxy;
-  }
-  memset(pNew, 0, sizeof(unixFile));
-  pNew->openFlags = openFlags;
-  memset(&dummyVfs, 0, sizeof(dummyVfs));
-  dummyVfs.pAppData = (void*)&autolockIoFinder;
-  dummyVfs.zName = "dummy";
-  pUnused->fd = fd;
-  pUnused->flags = openFlags;
-  pNew->pUnused = pUnused;
-  
-  rc = fillInUnixFile(&dummyVfs, fd, (sqlite3_file*)pNew, path, 0);
-  if( rc==SQLITE_OK ){
-    *ppFile = pNew;
-    return SQLITE_OK;
-  }
-end_create_proxy:    
-  robust_close(pNew, fd, __LINE__);
-  sqlite3_free(pNew);
-  sqlite3_free(pUnused);
-  return rc;
-}
-
-#ifdef SQLITE_TEST
-/* simulate multiple hosts by creating unique hostid file paths */
-SQLITE_API int sqlite3_hostid_num = 0;
-#endif
-
-#define PROXY_HOSTIDLEN    16  /* conch file host id length */
-
-/* Not always defined in the headers as it ought to be */
-extern int gethostuuid(uuid_t id, const struct timespec *wait);
-
-/* get the host ID via gethostuuid(), pHostID must point to PROXY_HOSTIDLEN 
-** bytes of writable memory.
-*/
-static int proxyGetHostID(unsigned char *pHostID, int *pError){
-  assert(PROXY_HOSTIDLEN == sizeof(uuid_t));
-  memset(pHostID, 0, PROXY_HOSTIDLEN);
-#if defined(__MAX_OS_X_VERSION_MIN_REQUIRED)\
-               && __MAC_OS_X_VERSION_MIN_REQUIRED<1050
-  {
-    static const struct timespec timeout = {1, 0}; /* 1 sec timeout */
-    if( gethostuuid(pHostID, &timeout) ){
-      int err = errno;
-      if( pError ){
-        *pError = err;
-      }
-      return SQLITE_IOERR;
-    }
-  }
-#else
-  UNUSED_PARAMETER(pError);
-#endif
-#ifdef SQLITE_TEST
-  /* simulate multiple hosts by creating unique hostid file paths */
-  if( sqlite3_hostid_num != 0){
-    pHostID[0] = (char)(pHostID[0] + (char)(sqlite3_hostid_num & 0xFF));
-  }
-#endif
-  
-  return SQLITE_OK;
-}
-
-/* The conch file contains the header, host id and lock file path
- */
-#define PROXY_CONCHVERSION 2   /* 1-byte header, 16-byte host id, path */
-#define PROXY_HEADERLEN    1   /* conch file header length */
-#define PROXY_PATHINDEX    (PROXY_HEADERLEN+PROXY_HOSTIDLEN)
-#define PROXY_MAXCONCHLEN  (PROXY_HEADERLEN+PROXY_HOSTIDLEN+MAXPATHLEN)
-
-/* 
-** Takes an open conch file, copies the contents to a new path and then moves 
-** it back.  The newly created file's file descriptor is assigned to the
-** conch file structure and finally the original conch file descriptor is 
-** closed.  Returns zero if successful.
-*/
-static int proxyBreakConchLock(unixFile *pFile, uuid_t myHostID){
-  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext; 
-  unixFile *conchFile = pCtx->conchFile;
-  char tPath[MAXPATHLEN];
-  char buf[PROXY_MAXCONCHLEN];
-  char *cPath = pCtx->conchFilePath;
-  size_t readLen = 0;
-  size_t pathLen = 0;
-  char errmsg[64] = "";
-  int fd = -1;
-  int rc = -1;
-  UNUSED_PARAMETER(myHostID);
-
-  /* create a new path by replace the trailing '-conch' with '-break' */
-  pathLen = strlcpy(tPath, cPath, MAXPATHLEN);
-  if( pathLen>MAXPATHLEN || pathLen<6 || 
-     (strlcpy(&tPath[pathLen-5], "break", 6) != 5) ){
-    sqlite3_snprintf(sizeof(errmsg),errmsg,"path error (len %d)",(int)pathLen);
-    goto end_breaklock;
-  }
-  /* read the conch content */
-  readLen = osPread(conchFile->h, buf, PROXY_MAXCONCHLEN, 0);
-  if( readLen<PROXY_PATHINDEX ){
-    sqlite3_snprintf(sizeof(errmsg),errmsg,"read error (len %d)",(int)readLen);
-    goto end_breaklock;
-  }
-  /* write it out to the temporary break file */
-  fd = robust_open(tPath, (O_RDWR|O_CREAT|O_EXCL), 0);
-  if( fd<0 ){
-    sqlite3_snprintf(sizeof(errmsg), errmsg, "create failed (%d)", errno);
-    goto end_breaklock;
-  }
-  if( osPwrite(fd, buf, readLen, 0) != (ssize_t)readLen ){
-    sqlite3_snprintf(sizeof(errmsg), errmsg, "write failed (%d)", errno);
-    goto end_breaklock;
-  }
-  if( rename(tPath, cPath) ){
-    sqlite3_snprintf(sizeof(errmsg), errmsg, "rename failed (%d)", errno);
-    goto end_breaklock;
-  }
-  rc = 0;
-  fprintf(stderr, "broke stale lock on %s\n", cPath);
-  robust_close(pFile, conchFile->h, __LINE__);
-  conchFile->h = fd;
-  conchFile->openFlags = O_RDWR | O_CREAT;
-
-end_breaklock:
-  if( rc ){
-    if( fd>=0 ){
-      osUnlink(tPath);
-      robust_close(pFile, fd, __LINE__);
-    }
-    fprintf(stderr, "failed to break stale lock on %s, %s\n", cPath, errmsg);
-  }
-  return rc;
-}
-
-/* Take the requested lock on the conch file and break a stale lock if the 
-** host id matches.
-*/
-static int proxyConchLock(unixFile *pFile, uuid_t myHostID, int lockType){
-  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext; 
-  unixFile *conchFile = pCtx->conchFile;
-  int rc = SQLITE_OK;
-  int nTries = 0;
-  struct timespec conchModTime;
-  
-  memset(&conchModTime, 0, sizeof(conchModTime));
-  do {
-    rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
-    nTries ++;
-    if( rc==SQLITE_BUSY ){
-      /* If the lock failed (busy):
-       * 1st try: get the mod time of the conch, wait 0.5s and try again. 
-       * 2nd try: fail if the mod time changed or host id is different, wait 
-       *           10 sec and try again
-       * 3rd try: break the lock unless the mod time has changed.
-       */
-      struct stat buf;
-      if( osFstat(conchFile->h, &buf) ){
-        pFile->lastErrno = errno;
-        return SQLITE_IOERR_LOCK;
-      }
-      
-      if( nTries==1 ){
-        conchModTime = buf.st_mtimespec;
-        usleep(500000); /* wait 0.5 sec and try the lock again*/
-        continue;  
-      }
-
-      assert( nTries>1 );
-      if( conchModTime.tv_sec != buf.st_mtimespec.tv_sec || 
-         conchModTime.tv_nsec != buf.st_mtimespec.tv_nsec ){
-        return SQLITE_BUSY;
-      }
-      
-      if( nTries==2 ){  
-        char tBuf[PROXY_MAXCONCHLEN];
-        int len = osPread(conchFile->h, tBuf, PROXY_MAXCONCHLEN, 0);
-        if( len<0 ){
-          pFile->lastErrno = errno;
-          return SQLITE_IOERR_LOCK;
-        }
-        if( len>PROXY_PATHINDEX && tBuf[0]==(char)PROXY_CONCHVERSION){
-          /* don't break the lock if the host id doesn't match */
-          if( 0!=memcmp(&tBuf[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN) ){
-            return SQLITE_BUSY;
-          }
-        }else{
-          /* don't break the lock on short read or a version mismatch */
-          return SQLITE_BUSY;
-        }
-        usleep(10000000); /* wait 10 sec and try the lock again */
-        continue; 
-      }
-      
-      assert( nTries==3 );
-      if( 0==proxyBreakConchLock(pFile, myHostID) ){
-        rc = SQLITE_OK;
-        if( lockType==EXCLUSIVE_LOCK ){
-          rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, SHARED_LOCK);          
-        }
-        if( !rc ){
-          rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
-        }
-      }
-    }
-  } while( rc==SQLITE_BUSY && nTries<3 );
-  
-  return rc;
-}
-
-/* Takes the conch by taking a shared lock and read the contents conch, if 
-** lockPath is non-NULL, the host ID and lock file path must match.  A NULL 
-** lockPath means that the lockPath in the conch file will be used if the 
-** host IDs match, or a new lock path will be generated automatically 
-** and written to the conch file.
-*/
-static int proxyTakeConch(unixFile *pFile){
-  proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext; 
-  
-  if( pCtx->conchHeld!=0 ){
-    return SQLITE_OK;
-  }else{
-    unixFile *conchFile = pCtx->conchFile;
-    uuid_t myHostID;
-    int pError = 0;
-    char readBuf[PROXY_MAXCONCHLEN];
-    char lockPath[MAXPATHLEN];
-    char *tempLockPath = NULL;
-    int rc = SQLITE_OK;
-    int createConch = 0;
-    int hostIdMatch = 0;
-    int readLen = 0;
-    int tryOldLockPath = 0;
-    int forceNewLockPath = 0;
-    
-    OSTRACE(("TAKECONCH  %d for %s pid=%d\n", conchFile->h,
-             (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), getpid()));
-
-    rc = proxyGetHostID(myHostID, &pError);
-    if( (rc&0xff)==SQLITE_IOERR ){
-      pFile->lastErrno = pError;
-      goto end_takeconch;
-    }
-    rc = proxyConchLock(pFile, myHostID, SHARED_LOCK);
-    if( rc!=SQLITE_OK ){
-      goto end_takeconch;
-    }
-    /* read the existing conch file */
-    readLen = seekAndRead((unixFile*)conchFile, 0, readBuf, PROXY_MAXCONCHLEN);
-    if( readLen<0 ){
-      /* I/O error: lastErrno set by seekAndRead */
-      pFile->lastErrno = conchFile->lastErrno;
-      rc = SQLITE_IOERR_READ;
-      goto end_takeconch;
-    }else if( readLen<=(PROXY_HEADERLEN+PROXY_HOSTIDLEN) || 
-             readBuf[0]!=(char)PROXY_CONCHVERSION ){
-      /* a short read or version format mismatch means we need to create a new 
-      ** conch file. 
-      */
-      createConch = 1;
-    }
-    /* if the host id matches and the lock path already exists in the conch
-    ** we'll try to use the path there, if we can't open that path, we'll 
-    ** retry with a new auto-generated path 
-    */
-    do { /* in case we need to try again for an :auto: named lock file */
-
-      if( !createConch && !forceNewLockPath ){
-        hostIdMatch = !memcmp(&readBuf[PROXY_HEADERLEN], myHostID, 
-                                  PROXY_HOSTIDLEN);
-        /* if the conch has data compare the contents */
-        if( !pCtx->lockProxyPath ){
-          /* for auto-named local lock file, just check the host ID and we'll
-           ** use the local lock file path that's already in there
-           */
-          if( hostIdMatch ){
-            size_t pathLen = (readLen - PROXY_PATHINDEX);
-            
-            if( pathLen>=MAXPATHLEN ){
-              pathLen=MAXPATHLEN-1;
-            }
-            memcpy(lockPath, &readBuf[PROXY_PATHINDEX], pathLen);
-            lockPath[pathLen] = 0;
-            tempLockPath = lockPath;
-            tryOldLockPath = 1;
-            /* create a copy of the lock path if the conch is taken */
-            goto end_takeconch;
-          }
-        }else if( hostIdMatch
-               && !strncmp(pCtx->lockProxyPath, &readBuf[PROXY_PATHINDEX],
-                           readLen-PROXY_PATHINDEX)
-        ){
-          /* conch host and lock path match */
-          goto end_takeconch; 
-        }
-      }
-      
-      /* if the conch isn't writable and doesn't match, we can't take it */
-      if( (conchFile->openFlags&O_RDWR) == 0 ){
-        rc = SQLITE_BUSY;
-        goto end_takeconch;
-      }
-      
-      /* either the conch didn't match or we need to create a new one */
-      if( !pCtx->lockProxyPath ){
-        proxyGetLockPath(pCtx->dbPath, lockPath, MAXPATHLEN);
-        tempLockPath = lockPath;
-        /* create a copy of the lock path _only_ if the conch is taken */
-      }
-      
-      /* update conch with host and path (this will fail if other process
-      ** has a shared lock already), if the host id matches, use the big
-      ** stick.
-      */
-      futimes(conchFile->h, NULL);
-      if( hostIdMatch && !createConch ){
-        if( conchFile->pInode && conchFile->pInode->nShared>1 ){
-          /* We are trying for an exclusive lock but another thread in this
-           ** same process is still holding a shared lock. */
-          rc = SQLITE_BUSY;
-        } else {          
-          rc = proxyConchLock(pFile, myHostID, EXCLUSIVE_LOCK);
-        }
-      }else{
-        rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, EXCLUSIVE_LOCK);
-      }
-      if( rc==SQLITE_OK ){
-        char writeBuffer[PROXY_MAXCONCHLEN];
-        int writeSize = 0;
-        
-        writeBuffer[0] = (char)PROXY_CONCHVERSION;
-        memcpy(&writeBuffer[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN);
-        if( pCtx->lockProxyPath!=NULL ){
-          strlcpy(&writeBuffer[PROXY_PATHINDEX], pCtx->lockProxyPath, MAXPATHLEN);
-        }else{
-          strlcpy(&writeBuffer[PROXY_PATHINDEX], tempLockPath, MAXPATHLEN);
-        }
-        writeSize = PROXY_PATHINDEX + strlen(&writeBuffer[PROXY_PATHINDEX]);
-        robust_ftruncate(conchFile->h, writeSize);
-        rc = unixWrite((sqlite3_file *)conchFile, writeBuffer, writeSize, 0);
-        fsync(conchFile->h);
-        /* If we created a new conch file (not just updated the contents of a 
-         ** valid conch file), try to match the permissions of the database 
-         */
-        if( rc==SQLITE_OK && createConch ){
-          struct stat buf;
-          int err = osFstat(pFile->h, &buf);
-          if( err==0 ){
-            mode_t cmode = buf.st_mode&(S_IRUSR|S_IWUSR | S_IRGRP|S_IWGRP |
-                                        S_IROTH|S_IWOTH);
-            /* try to match the database file R/W permissions, ignore failure */
-#ifndef SQLITE_PROXY_DEBUG
-            osFchmod(conchFile->h, cmode);
-#else
-            do{
-              rc = osFchmod(conchFile->h, cmode);
-            }while( rc==(-1) && errno==EINTR );
-            if( rc!=0 ){
-              int code = errno;
-              fprintf(stderr, "fchmod %o FAILED with %d %s\n",
-                      cmode, code, strerror(code));
-            } else {
-              fprintf(stderr, "fchmod %o SUCCEDED\n",cmode);
-            }
-          }else{
-            int code = errno;
-            fprintf(stderr, "STAT FAILED[%d] with %d %s\n", 
-                    err, code, strerror(code));
-#endif
-          }
-        }
-      }
-      conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, SHARED_LOCK);
-      
-    end_takeconch:
-      OSTRACE(("TRANSPROXY: CLOSE  %d\n", pFile->h));
-      if( rc==SQLITE_OK && pFile->openFlags ){
-        int fd;
-        if( pFile->h>=0 ){
-          robust_close(pFile, pFile->h, __LINE__);
-        }
-        pFile->h = -1;
-        fd = robust_open(pCtx->dbPath, pFile->openFlags, 0);
-        OSTRACE(("TRANSPROXY: OPEN  %d\n", fd));
-        if( fd>=0 ){
-          pFile->h = fd;
-        }else{
-          rc=SQLITE_CANTOPEN_BKPT; /* SQLITE_BUSY? proxyTakeConch called
-           during locking */
-        }
-      }
-      if( rc==SQLITE_OK && !pCtx->lockProxy ){
-        char *path = tempLockPath ? tempLockPath : pCtx->lockProxyPath;
-        rc = proxyCreateUnixFile(path, &pCtx->lockProxy, 1);
-        if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM && tryOldLockPath ){
-          /* we couldn't create the proxy lock file with the old lock file path
-           ** so try again via auto-naming 
-           */
-          forceNewLockPath = 1;
-          tryOldLockPath = 0;
-          continue; /* go back to the do {} while start point, try again */
-        }
-      }
-      if( rc==SQLITE_OK ){
-        /* Need to make a copy of path if we extracted the value
-         ** from the conch file or the path was allocated on the stack
-         */
-        if( tempLockPath ){
-          pCtx->lockProxyPath = sqlite3DbStrDup(0, tempLockPath);
-          if( !pCtx->lockProxyPath ){
-            rc = SQLITE_NOMEM;
-          }
-        }
-      }
-      if( rc==SQLITE_OK ){
-        pCtx->conchHeld = 1;
-        
-        if( pCtx->lockProxy->pMethod == &afpIoMethods ){
-          afpLockingContext *afpCtx;
-          afpCtx = (afpLockingContext *)pCtx->lockProxy->lockingContext;
-          afpCtx->dbPath = pCtx->lockProxyPath;
-        }
-      } else {
-        conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
-      }
-      OSTRACE(("TAKECONCH  %d %s\n", conchFile->h,
-               rc==SQLITE_OK?"ok":"failed"));
-      return rc;
-    } while (1); /* in case we need to retry the :auto: lock file - 
-                 ** we should never get here except via the 'continue' call. */
-  }
-}
-
-/*
-** If pFile holds a lock on a conch file, then release that lock.
-*/
-static int proxyReleaseConch(unixFile *pFile){
-  int rc = SQLITE_OK;         /* Subroutine return code */
-  proxyLockingContext *pCtx;  /* The locking context for the proxy lock */
-  unixFile *conchFile;        /* Name of the conch file */
-
-  pCtx = (proxyLockingContext *)pFile->lockingContext;
-  conchFile = pCtx->conchFile;
-  OSTRACE(("RELEASECONCH  %d for %s pid=%d\n", conchFile->h,
-           (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), 
-           getpid()));
-  if( pCtx->conchHeld>0 ){
-    rc = conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
-  }
-  pCtx->conchHeld = 0;
-  OSTRACE(("RELEASECONCH  %d %s\n", conchFile->h,
-           (rc==SQLITE_OK ? "ok" : "failed")));
-  return rc;
-}
-
-/*
-** Given the name of a database file, compute the name of its conch file.
-** Store the conch filename in memory obtained from sqlite3_malloc().
-** Make *pConchPath point to the new name.  Return SQLITE_OK on success
-** or SQLITE_NOMEM if unable to obtain memory.
-**
-** The caller is responsible for ensuring that the allocated memory
-** space is eventually freed.
-**
-** *pConchPath is set to NULL if a memory allocation error occurs.
-*/
-static int proxyCreateConchPathname(char *dbPath, char **pConchPath){
-  int i;                        /* Loop counter */
-  int len = (int)strlen(dbPath); /* Length of database filename - dbPath */
-  char *conchPath;              /* buffer in which to construct conch name */
-
-  /* Allocate space for the conch filename and initialize the name to
-  ** the name of the original database file. */  
-  *pConchPath = conchPath = (char *)sqlite3_malloc(len + 8);
-  if( conchPath==0 ){
-    return SQLITE_NOMEM;
-  }
-  memcpy(conchPath, dbPath, len+1);
-  
-  /* now insert a "." before the last / character */
-  for( i=(len-1); i>=0; i-- ){
-    if( conchPath[i]=='/' ){
-      i++;
-      break;
-    }
-  }
-  conchPath[i]='.';
-  while ( i<len ){
-    conchPath[i+1]=dbPath[i];
-    i++;
-  }
-
-  /* append the "-conch" suffix to the file */
-  memcpy(&conchPath[i+1], "-conch", 7);
-  assert( (int)strlen(conchPath) == len+7 );
-
-  return SQLITE_OK;
-}
-
-
-/* Takes a fully configured proxy locking-style unix file and switches
-** the local lock file path 
-*/
-static int switchLockProxyPath(unixFile *pFile, const char *path) {
-  proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
-  char *oldPath = pCtx->lockProxyPath;
-  int rc = SQLITE_OK;
-
-  if( pFile->eFileLock!=NO_LOCK ){
-    return SQLITE_BUSY;
-  }  
-
-  /* nothing to do if the path is NULL, :auto: or matches the existing path */
-  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ||
-    (oldPath && !strncmp(oldPath, path, MAXPATHLEN)) ){
-    return SQLITE_OK;
-  }else{
-    unixFile *lockProxy = pCtx->lockProxy;
-    pCtx->lockProxy=NULL;
-    pCtx->conchHeld = 0;
-    if( lockProxy!=NULL ){
-      rc=lockProxy->pMethod->xClose((sqlite3_file *)lockProxy);
-      if( rc ) return rc;
-      sqlite3_free(lockProxy);
-    }
-    sqlite3_free(oldPath);
-    pCtx->lockProxyPath = sqlite3DbStrDup(0, path);
-  }
-  
-  return rc;
-}
-
-/*
-** pFile is a file that has been opened by a prior xOpen call.  dbPath
-** is a string buffer at least MAXPATHLEN+1 characters in size.
-**
-** This routine find the filename associated with pFile and writes it
-** int dbPath.
-*/
-static int proxyGetDbPathForUnixFile(unixFile *pFile, char *dbPath){
-#if defined(__APPLE__)
-  if( pFile->pMethod == &afpIoMethods ){
-    /* afp style keeps a reference to the db path in the filePath field 
-    ** of the struct */
-    assert( (int)strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
-    strlcpy(dbPath, ((afpLockingContext *)pFile->lockingContext)->dbPath, MAXPATHLEN);
-  } else
-#endif
-  if( pFile->pMethod == &dotlockIoMethods ){
-    /* dot lock style uses the locking context to store the dot lock
-    ** file path */
-    int len = strlen((char *)pFile->lockingContext) - strlen(DOTLOCK_SUFFIX);
-    memcpy(dbPath, (char *)pFile->lockingContext, len + 1);
-  }else{
-    /* all other styles use the locking context to store the db file path */
-    assert( strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
-    strlcpy(dbPath, (char *)pFile->lockingContext, MAXPATHLEN);
-  }
-  return SQLITE_OK;
-}
-
-/*
-** Takes an already filled in unix file and alters it so all file locking 
-** will be performed on the local proxy lock file.  The following fields
-** are preserved in the locking context so that they can be restored and 
-** the unix structure properly cleaned up at close time:
-**  ->lockingContext
-**  ->pMethod
-*/
-static int proxyTransformUnixFile(unixFile *pFile, const char *path) {
-  proxyLockingContext *pCtx;
-  char dbPath[MAXPATHLEN+1];       /* Name of the database file */
-  char *lockPath=NULL;
-  int rc = SQLITE_OK;
-  
-  if( pFile->eFileLock!=NO_LOCK ){
-    return SQLITE_BUSY;
-  }
-  proxyGetDbPathForUnixFile(pFile, dbPath);
-  if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ){
-    lockPath=NULL;
-  }else{
-    lockPath=(char *)path;
-  }
-  
-  OSTRACE(("TRANSPROXY  %d for %s pid=%d\n", pFile->h,
-           (lockPath ? lockPath : ":auto:"), getpid()));
-
-  pCtx = sqlite3_malloc( sizeof(*pCtx) );
-  if( pCtx==0 ){
-    return SQLITE_NOMEM;
-  }
-  memset(pCtx, 0, sizeof(*pCtx));
-
-  rc = proxyCreateConchPathname(dbPath, &pCtx->conchFilePath);
-  if( rc==SQLITE_OK ){
-    rc = proxyCreateUnixFile(pCtx->conchFilePath, &pCtx->conchFile, 0);
-    if( rc==SQLITE_CANTOPEN && ((pFile->openFlags&O_RDWR) == 0) ){
-      /* if (a) the open flags are not O_RDWR, (b) the conch isn't there, and
-      ** (c) the file system is read-only, then enable no-locking access.
-      ** Ugh, since O_RDONLY==0x0000 we test for !O_RDWR since unixOpen asserts
-      ** that openFlags will have only one of O_RDONLY or O_RDWR.
-      */
-      struct statfs fsInfo;
-      struct stat conchInfo;
-      int goLockless = 0;
-
-      if( osStat(pCtx->conchFilePath, &conchInfo) == -1 ) {
-        int err = errno;
-        if( (err==ENOENT) && (statfs(dbPath, &fsInfo) != -1) ){
-          goLockless = (fsInfo.f_flags&MNT_RDONLY) == MNT_RDONLY;
-        }
-      }
-      if( goLockless ){
-        pCtx->conchHeld = -1; /* read only FS/ lockless */
-        rc = SQLITE_OK;
-      }
-    }
-  }  
-  if( rc==SQLITE_OK && lockPath ){
-    pCtx->lockProxyPath = sqlite3DbStrDup(0, lockPath);
-  }
-
-  if( rc==SQLITE_OK ){
-    pCtx->dbPath = sqlite3DbStrDup(0, dbPath);
-    if( pCtx->dbPath==NULL ){
-      rc = SQLITE_NOMEM;
-    }
-  }
-  if( rc==SQLITE_OK ){
-    /* all memory is allocated, proxys are created and assigned, 
-    ** switch the locking context and pMethod then return.
-    */
-    pCtx->oldLockingContext = pFile->lockingContext;
-    pFile->lockingContext = pCtx;
-    pCtx->pOldMethod = pFile->pMethod;
-    pFile->pMethod = &proxyIoMethods;
-  }else{
-    if( pCtx->conchFile ){ 
-      pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
-      sqlite3_free(pCtx->conchFile);
-    }
-    sqlite3DbFree(0, pCtx->lockProxyPath);
-    sqlite3_free(pCtx->conchFilePath); 
-    sqlite3_free(pCtx);
-  }
-  OSTRACE(("TRANSPROXY  %d %s\n", pFile->h,
-           (rc==SQLITE_OK ? "ok" : "failed")));
-  return rc;
-}
-
-
-/*
-** This routine handles sqlite3_file_control() calls that are specific
-** to proxy locking.
-*/
-static int proxyFileControl(sqlite3_file *id, int op, void *pArg){
-  switch( op ){
-    case SQLITE_GET_LOCKPROXYFILE: {
-      unixFile *pFile = (unixFile*)id;
-      if( pFile->pMethod == &proxyIoMethods ){
-        proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
-        proxyTakeConch(pFile);
-        if( pCtx->lockProxyPath ){
-          *(const char **)pArg = pCtx->lockProxyPath;
-        }else{
-          *(const char **)pArg = ":auto: (not held)";
-        }
-      } else {
-        *(const char **)pArg = NULL;
-      }
-      return SQLITE_OK;
-    }
-    case SQLITE_SET_LOCKPROXYFILE: {
-      unixFile *pFile = (unixFile*)id;
-      int rc = SQLITE_OK;
-      int isProxyStyle = (pFile->pMethod == &proxyIoMethods);
-      if( pArg==NULL || (const char *)pArg==0 ){
-        if( isProxyStyle ){
-          /* turn off proxy locking - not supported */
-          rc = SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
-        }else{
-          /* turn off proxy locking - already off - NOOP */
-          rc = SQLITE_OK;
-        }
-      }else{
-        const char *proxyPath = (const char *)pArg;
-        if( isProxyStyle ){
-          proxyLockingContext *pCtx = 
-            (proxyLockingContext*)pFile->lockingContext;
-          if( !strcmp(pArg, ":auto:") 
-           || (pCtx->lockProxyPath &&
-               !strncmp(pCtx->lockProxyPath, proxyPath, MAXPATHLEN))
-          ){
-            rc = SQLITE_OK;
-          }else{
-            rc = switchLockProxyPath(pFile, proxyPath);
-          }
-        }else{
-          /* turn on proxy file locking */
-          rc = proxyTransformUnixFile(pFile, proxyPath);
-        }
-      }
-      return rc;
-    }
-    default: {
-      assert( 0 );  /* The call assures that only valid opcodes are sent */
-    }
-  }
-  /*NOTREACHED*/
-  return SQLITE_ERROR;
-}
-
-/*
-** Within this division (the proxying locking implementation) the procedures
-** above this point are all utilities.  The lock-related methods of the
-** proxy-locking sqlite3_io_method object follow.
-*/
-
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
-*/
-static int proxyCheckReservedLock(sqlite3_file *id, int *pResOut) {
-  unixFile *pFile = (unixFile*)id;
-  int rc = proxyTakeConch(pFile);
-  if( rc==SQLITE_OK ){
-    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
-    if( pCtx->conchHeld>0 ){
-      unixFile *proxy = pCtx->lockProxy;
-      return proxy->pMethod->xCheckReservedLock((sqlite3_file*)proxy, pResOut);
-    }else{ /* conchHeld < 0 is lockless */
-      pResOut=0;
-    }
-  }
-  return rc;
-}
-
-/*
-** Lock the file with the lock specified by parameter eFileLock - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** This routine will only increase a lock.  Use the sqlite3OsUnlock()
-** routine to lower a locking level.
-*/
-static int proxyLock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  int rc = proxyTakeConch(pFile);
-  if( rc==SQLITE_OK ){
-    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
-    if( pCtx->conchHeld>0 ){
-      unixFile *proxy = pCtx->lockProxy;
-      rc = proxy->pMethod->xLock((sqlite3_file*)proxy, eFileLock);
-      pFile->eFileLock = proxy->eFileLock;
-    }else{
-      /* conchHeld < 0 is lockless */
-    }
-  }
-  return rc;
-}
-
-
-/*
-** Lower the locking level on file descriptor pFile to eFileLock.  eFileLock
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-*/
-static int proxyUnlock(sqlite3_file *id, int eFileLock) {
-  unixFile *pFile = (unixFile*)id;
-  int rc = proxyTakeConch(pFile);
-  if( rc==SQLITE_OK ){
-    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
-    if( pCtx->conchHeld>0 ){
-      unixFile *proxy = pCtx->lockProxy;
-      rc = proxy->pMethod->xUnlock((sqlite3_file*)proxy, eFileLock);
-      pFile->eFileLock = proxy->eFileLock;
-    }else{
-      /* conchHeld < 0 is lockless */
-    }
-  }
-  return rc;
-}
-
-/*
-** Close a file that uses proxy locks.
-*/
-static int proxyClose(sqlite3_file *id) {
-  if( id ){
-    unixFile *pFile = (unixFile*)id;
-    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
-    unixFile *lockProxy = pCtx->lockProxy;
-    unixFile *conchFile = pCtx->conchFile;
-    int rc = SQLITE_OK;
-    
-    if( lockProxy ){
-      rc = lockProxy->pMethod->xUnlock((sqlite3_file*)lockProxy, NO_LOCK);
-      if( rc ) return rc;
-      rc = lockProxy->pMethod->xClose((sqlite3_file*)lockProxy);
-      if( rc ) return rc;
-      sqlite3_free(lockProxy);
-      pCtx->lockProxy = 0;
-    }
-    if( conchFile ){
-      if( pCtx->conchHeld ){
-        rc = proxyReleaseConch(pFile);
-        if( rc ) return rc;
-      }
-      rc = conchFile->pMethod->xClose((sqlite3_file*)conchFile);
-      if( rc ) return rc;
-      sqlite3_free(conchFile);
-    }
-    sqlite3DbFree(0, pCtx->lockProxyPath);
-    sqlite3_free(pCtx->conchFilePath);
-    sqlite3DbFree(0, pCtx->dbPath);
-    /* restore the original locking context and pMethod then close it */
-    pFile->lockingContext = pCtx->oldLockingContext;
-    pFile->pMethod = pCtx->pOldMethod;
-    sqlite3_free(pCtx);
-    return pFile->pMethod->xClose(id);
-  }
-  return SQLITE_OK;
-}
-
-
-
-#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
-/*
-** The proxy locking style is intended for use with AFP filesystems.
-** And since AFP is only supported on MacOSX, the proxy locking is also
-** restricted to MacOSX.
-** 
-**
-******************* End of the proxy lock implementation **********************
-******************************************************************************/
-
-/*
-** Initialize the operating system interface.
-**
-** This routine registers all VFS implementations for unix-like operating
-** systems.  This routine, and the sqlite3_os_end() routine that follows,
-** should be the only routines in this file that are visible from other
-** files.
-**
-** This routine is called once during SQLite initialization and by a
-** single thread.  The memory allocation and mutex subsystems have not
-** necessarily been initialized when this routine is called, and so they
-** should not be used.
-*/
-SQLITE_API int sqlite3_os_init(void){ 
-  /* 
-  ** The following macro defines an initializer for an sqlite3_vfs object.
-  ** The name of the VFS is NAME.  The pAppData is a pointer to a pointer
-  ** to the "finder" function.  (pAppData is a pointer to a pointer because
-  ** silly C90 rules prohibit a void* from being cast to a function pointer
-  ** and so we have to go through the intermediate pointer to avoid problems
-  ** when compiling with -pedantic-errors on GCC.)
-  **
-  ** The FINDER parameter to this macro is the name of the pointer to the
-  ** finder-function.  The finder-function returns a pointer to the
-  ** sqlite_io_methods object that implements the desired locking
-  ** behaviors.  See the division above that contains the IOMETHODS
-  ** macro for addition information on finder-functions.
-  **
-  ** Most finders simply return a pointer to a fixed sqlite3_io_methods
-  ** object.  But the "autolockIoFinder" available on MacOSX does a little
-  ** more than that; it looks at the filesystem type that hosts the 
-  ** database file and tries to choose an locking method appropriate for
-  ** that filesystem time.
-  */
-  #define UNIXVFS(VFSNAME, FINDER) {                        \
-    3,                    /* iVersion */                    \
-    sizeof(unixFile),     /* szOsFile */                    \
-    MAX_PATHNAME,         /* mxPathname */                  \
-    0,                    /* pNext */                       \
-    VFSNAME,              /* zName */                       \
-    (void*)&FINDER,       /* pAppData */                    \
-    unixOpen,             /* xOpen */                       \
-    unixDelete,           /* xDelete */                     \
-    unixAccess,           /* xAccess */                     \
-    unixFullPathname,     /* xFullPathname */               \
-    unixDlOpen,           /* xDlOpen */                     \
-    unixDlError,          /* xDlError */                    \
-    unixDlSym,            /* xDlSym */                      \
-    unixDlClose,          /* xDlClose */                    \
-    unixRandomness,       /* xRandomness */                 \
-    unixSleep,            /* xSleep */                      \
-    unixCurrentTime,      /* xCurrentTime */                \
-    unixGetLastError,     /* xGetLastError */               \
-    unixCurrentTimeInt64, /* xCurrentTimeInt64 */           \
-    unixSetSystemCall,    /* xSetSystemCall */              \
-    unixGetSystemCall,    /* xGetSystemCall */              \
-    unixNextSystemCall,   /* xNextSystemCall */             \
-  }
-
-  /*
-  ** All default VFSes for unix are contained in the following array.
-  **
-  ** Note that the sqlite3_vfs.pNext field of the VFS object is modified
-  ** by the SQLite core when the VFS is registered.  So the following
-  ** array cannot be const.
-  */
-  static sqlite3_vfs aVfs[] = {
-#if SQLITE_ENABLE_LOCKING_STYLE && (OS_VXWORKS || defined(__APPLE__))
-    UNIXVFS("unix",          autolockIoFinder ),
-#else
-    UNIXVFS("unix",          posixIoFinder ),
-#endif
-    UNIXVFS("unix-none",     nolockIoFinder ),
-    UNIXVFS("unix-dotfile",  dotlockIoFinder ),
-    UNIXVFS("unix-excl",     posixIoFinder ),
-#if OS_VXWORKS
-    UNIXVFS("unix-namedsem", semIoFinder ),
-#endif
-#if SQLITE_ENABLE_LOCKING_STYLE
-    UNIXVFS("unix-posix",    posixIoFinder ),
-#if !OS_VXWORKS
-    UNIXVFS("unix-flock",    flockIoFinder ),
-#endif
-#endif
-#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
-    UNIXVFS("unix-afp",      afpIoFinder ),
-    UNIXVFS("unix-nfs",      nfsIoFinder ),
-    UNIXVFS("unix-proxy",    proxyIoFinder ),
-#endif
-  };
-  unsigned int i;          /* Loop counter */
-
-  /* Double-check that the aSyscall[] array has been constructed
-  ** correctly.  See ticket [bb3a86e890c8e96ab] */
-  assert( ArraySize(aSyscall)==24 );
-
-  /* Register all VFSes defined in the aVfs[] array */
-  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
-    sqlite3_vfs_register(&aVfs[i], i==0);
-  }
-  return SQLITE_OK; 
-}
-
-/*
-** Shutdown the operating system interface.
-**
-** Some operating systems might need to do some cleanup in this routine,
-** to release dynamically allocated objects.  But not on unix.
-** This routine is a no-op for unix.
-*/
-SQLITE_API int sqlite3_os_end(void){ 
-  return SQLITE_OK; 
-}
- 
-#endif /* SQLITE_OS_UNIX */
-
-/************** End of os_unix.c *********************************************/
-/************** Begin file os_win.c ******************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains code that is specific to Windows.
-*/
-#if SQLITE_OS_WIN               /* This file is used for Windows only */
-
-#ifdef __CYGWIN__
-# include <sys/cygwin.h>
-# include <errno.h> /* amalgamator: keep */
-#endif
-
-/*
-** Include code that is common to all os_*.c files
-*/
-/************** Include os_common.h in the middle of os_win.c ****************/
-/************** Begin file os_common.h ***************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains macros and a little bit of code that is common to
-** all of the platform-specific files (os_*.c) and is #included into those
-** files.
-**
-** This file should be #included by the os_*.c files only.  It is not a
-** general purpose header file.
-*/
-#ifndef _OS_COMMON_H_
-#define _OS_COMMON_H_
-
-/*
-** At least two bugs have slipped in because we changed the MEMORY_DEBUG
-** macro to SQLITE_DEBUG and some older makefiles have not yet made the
-** switch.  The following code should catch this problem at compile-time.
-*/
-#ifdef MEMORY_DEBUG
-# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
-#endif
-
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-# ifndef SQLITE_DEBUG_OS_TRACE
-#   define SQLITE_DEBUG_OS_TRACE 0
-# endif
-  int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
-# define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
-#else
-# define OSTRACE(X)
-#endif
-
-/*
-** Macros for performance tracing.  Normally turned off.  Only works
-** on i486 hardware.
-*/
-#ifdef SQLITE_PERFORMANCE_TRACE
-
-/* 
-** hwtime.h contains inline assembler code for implementing 
-** high-performance timing routines.
-*/
-/************** Include hwtime.h in the middle of os_common.h ****************/
-/************** Begin file hwtime.h ******************************************/
-/*
-** 2008 May 27
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains inline asm code for retrieving "high-performance"
-** counters for x86 class CPUs.
-*/
-#ifndef _HWTIME_H_
-#define _HWTIME_H_
-
-/*
-** The following routine only works on pentium-class (or newer) processors.
-** It uses the RDTSC opcode to read the cycle count value out of the
-** processor and returns that value.  This can be used for high-res
-** profiling.
-*/
-#if (defined(__GNUC__) || defined(_MSC_VER)) && \
-      (defined(i386) || defined(__i386__) || defined(_M_IX86))
-
-  #if defined(__GNUC__)
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-     unsigned int lo, hi;
-     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
-     return (sqlite_uint64)hi << 32 | lo;
-  }
-
-  #elif defined(_MSC_VER)
-
-  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
-     __asm {
-        rdtsc
-        ret       ; return value at EDX:EAX
-     }
-  }
-
-  #endif
-
-#elif (defined(__GNUC__) && defined(__x86_64__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long val;
-      __asm__ __volatile__ ("rdtsc" : "=A" (val));
-      return val;
-  }
- 
-#elif (defined(__GNUC__) && defined(__ppc__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long long retval;
-      unsigned long junk;
-      __asm__ __volatile__ ("\n\
-          1:      mftbu   %1\n\
-                  mftb    %L0\n\
-                  mftbu   %0\n\
-                  cmpw    %0,%1\n\
-                  bne     1b"
-                  : "=r" (retval), "=r" (junk));
-      return retval;
-  }
-
-#else
-
-  #error Need implementation of sqlite3Hwtime() for your platform.
-
-  /*
-  ** To compile without implementing sqlite3Hwtime() for your platform,
-  ** you can remove the above #error and use the following
-  ** stub function.  You will lose timing support for many
-  ** of the debugging and testing utilities, but it should at
-  ** least compile and run.
-  */
-SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
-
-#endif
-
-#endif /* !defined(_HWTIME_H_) */
-
-/************** End of hwtime.h **********************************************/
-/************** Continuing where we left off in os_common.h ******************/
-
-static sqlite_uint64 g_start;
-static sqlite_uint64 g_elapsed;
-#define TIMER_START       g_start=sqlite3Hwtime()
-#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
-#define TIMER_ELAPSED     g_elapsed
-#else
-#define TIMER_START
-#define TIMER_END
-#define TIMER_ELAPSED     ((sqlite_uint64)0)
-#endif
-
-/*
-** If we compile with the SQLITE_TEST macro set, then the following block
-** of code will give us the ability to simulate a disk I/O error.  This
-** is used for testing the I/O recovery logic.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
-SQLITE_API int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
-SQLITE_API int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
-SQLITE_API int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
-SQLITE_API int sqlite3_io_error_benign = 0;         /* True if errors are benign */
-SQLITE_API int sqlite3_diskfull_pending = 0;
-SQLITE_API int sqlite3_diskfull = 0;
-#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
-#define SimulateIOError(CODE)  \
-  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
-       || sqlite3_io_error_pending-- == 1 )  \
-              { local_ioerr(); CODE; }
-static void local_ioerr(){
-  IOTRACE(("IOERR\n"));
-  sqlite3_io_error_hit++;
-  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
-}
-#define SimulateDiskfullError(CODE) \
-   if( sqlite3_diskfull_pending ){ \
-     if( sqlite3_diskfull_pending == 1 ){ \
-       local_ioerr(); \
-       sqlite3_diskfull = 1; \
-       sqlite3_io_error_hit = 1; \
-       CODE; \
-     }else{ \
-       sqlite3_diskfull_pending--; \
-     } \
-   }
-#else
-#define SimulateIOErrorBenign(X)
-#define SimulateIOError(A)
-#define SimulateDiskfullError(A)
-#endif
-
-/*
-** When testing, keep a count of the number of open files.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_open_file_count = 0;
-#define OpenCounter(X)  sqlite3_open_file_count+=(X)
-#else
-#define OpenCounter(X)
-#endif
-
-#endif /* !defined(_OS_COMMON_H_) */
-
-/************** End of os_common.h *******************************************/
-/************** Continuing where we left off in os_win.c *********************/
-
-/*
-** Compiling and using WAL mode requires several APIs that are only
-** available in Windows platforms based on the NT kernel.
-*/
-#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
-#  error "WAL mode requires support from the Windows NT kernel, compile\
- with SQLITE_OMIT_WAL."
-#endif
-
-/*
-** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
-** based on the sub-platform)?
-*/
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
-#  define SQLITE_WIN32_HAS_ANSI
-#endif
-
-/*
-** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
-** based on the sub-platform)?
-*/
-#if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
-    !defined(SQLITE_WIN32_NO_WIDE)
-#  define SQLITE_WIN32_HAS_WIDE
-#endif
-
-/*
-** Make sure at least one set of Win32 APIs is available.
-*/
-#if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
-#  error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
- must be defined."
-#endif
-
-/*
-** Maximum pathname length (in chars) for Win32.  This should normally be
-** MAX_PATH.
-*/
-#ifndef SQLITE_WIN32_MAX_PATH_CHARS
-#  define SQLITE_WIN32_MAX_PATH_CHARS   (MAX_PATH)
-#endif
-
-/*
-** Maximum pathname length (in chars) for WinNT.  This should normally be
-** 32767.
-*/
-#ifndef SQLITE_WINNT_MAX_PATH_CHARS
-#  define SQLITE_WINNT_MAX_PATH_CHARS   (32767)
-#endif
-
-/*
-** Maximum pathname length (in bytes) for Win32.  The MAX_PATH macro is in
-** characters, so we allocate 3 bytes per character assuming worst-case of
-** 4-bytes-per-character for UTF8.
-*/
-#ifndef SQLITE_WIN32_MAX_PATH_BYTES
-#  define SQLITE_WIN32_MAX_PATH_BYTES   (SQLITE_WIN32_MAX_PATH_CHARS*4)
-#endif
-
-/*
-** Maximum pathname length (in bytes) for WinNT.  This should normally be
-** 32767 * sizeof(WCHAR).
-*/
-#ifndef SQLITE_WINNT_MAX_PATH_BYTES
-#  define SQLITE_WINNT_MAX_PATH_BYTES   \
-                            (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
-#endif
-
-/*
-** Maximum error message length (in chars) for WinRT.
-*/
-#ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
-#  define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
-#endif
-
-/*
-** Returns non-zero if the character should be treated as a directory
-** separator.
-*/
-#ifndef winIsDirSep
-#  define winIsDirSep(a)                (((a) == '/') || ((a) == '\\'))
-#endif
-
-/*
-** This macro is used when a local variable is set to a value that is
-** [sometimes] not used by the code (e.g. via conditional compilation).
-*/
-#ifndef UNUSED_VARIABLE_VALUE
-#  define UNUSED_VARIABLE_VALUE(x) (void)(x)
-#endif
-
-/*
-** Returns the string that should be used as the directory separator.
-*/
-#ifndef winGetDirDep
-#  ifdef __CYGWIN__
-#    define winGetDirDep()              "/"
-#  else
-#    define winGetDirDep()              "\\"
-#  endif
-#endif
-
-/*
-** Do we need to manually define the Win32 file mapping APIs for use with WAL
-** mode (e.g. these APIs are available in the Windows CE SDK; however, they
-** are not present in the header file)?
-*/
-#if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
-/*
-** Two of the file mapping APIs are different under WinRT.  Figure out which
-** set we need.
-*/
-#if SQLITE_OS_WINRT
-WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
-        LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
-
-WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
-#else
-#if defined(SQLITE_WIN32_HAS_ANSI)
-WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
-        DWORD, DWORD, DWORD, LPCSTR);
-#endif /* defined(SQLITE_WIN32_HAS_ANSI) */
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
-        DWORD, DWORD, DWORD, LPCWSTR);
-#endif /* defined(SQLITE_WIN32_HAS_WIDE) */
-
-WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
-#endif /* SQLITE_OS_WINRT */
-
-/*
-** This file mapping API is common to both Win32 and WinRT.
-*/
-WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
-#endif /* SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL) */
-
-/*
-** Some Microsoft compilers lack this definition.
-*/
-#ifndef INVALID_FILE_ATTRIBUTES
-# define INVALID_FILE_ATTRIBUTES ((DWORD)-1) 
-#endif
-
-#ifndef FILE_FLAG_MASK
-# define FILE_FLAG_MASK          (0xFF3C0000)
-#endif
-
-#ifndef FILE_ATTRIBUTE_MASK
-# define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
-#endif
-
-#ifndef SQLITE_OMIT_WAL
-/* Forward references to structures used for WAL */
-typedef struct winShm winShm;           /* A connection to shared-memory */
-typedef struct winShmNode winShmNode;   /* A region of shared-memory */
-#endif
-
-/*
-** WinCE lacks native support for file locking so we have to fake it
-** with some code of our own.
-*/
-#if SQLITE_OS_WINCE
-typedef struct winceLock {
-  int nReaders;       /* Number of reader locks obtained */
-  BOOL bPending;      /* Indicates a pending lock has been obtained */
-  BOOL bReserved;     /* Indicates a reserved lock has been obtained */
-  BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
-} winceLock;
-#endif
-
-/*
-** The winFile structure is a subclass of sqlite3_file* specific to the win32
-** portability layer.
-*/
-typedef struct winFile winFile;
-struct winFile {
-  const sqlite3_io_methods *pMethod; /*** Must be first ***/
-  sqlite3_vfs *pVfs;      /* The VFS used to open this file */
-  HANDLE h;               /* Handle for accessing the file */
-  u8 locktype;            /* Type of lock currently held on this file */
-  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
-  u8 ctrlFlags;           /* Flags.  See WINFILE_* below */
-  DWORD lastErrno;        /* The Windows errno from the last I/O error */
-#ifndef SQLITE_OMIT_WAL
-  winShm *pShm;           /* Instance of shared memory on this file */
-#endif
-  const char *zPath;      /* Full pathname of this file */
-  int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
-#if SQLITE_OS_WINCE
-  LPWSTR zDeleteOnClose;  /* Name of file to delete when closing */
-  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
-  HANDLE hShared;         /* Shared memory segment used for locking */
-  winceLock local;        /* Locks obtained by this instance of winFile */
-  winceLock *shared;      /* Global shared lock memory for the file  */
-#endif
-#if SQLITE_MAX_MMAP_SIZE>0
-  int nFetchOut;                /* Number of outstanding xFetch references */
-  HANDLE hMap;                  /* Handle for accessing memory mapping */
-  void *pMapRegion;             /* Area memory mapped */
-  sqlite3_int64 mmapSize;       /* Usable size of mapped region */
-  sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
-  sqlite3_int64 mmapSizeMax;    /* Configured FCNTL_MMAP_SIZE value */
-#endif
-};
-
-/*
-** Allowed values for winFile.ctrlFlags
-*/
-#define WINFILE_RDONLY          0x02   /* Connection is read only */
-#define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
-#define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
-
-/*
- * The size of the buffer used by sqlite3_win32_write_debug().
- */
-#ifndef SQLITE_WIN32_DBG_BUF_SIZE
-#  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
-#endif
-
-/*
- * The value used with sqlite3_win32_set_directory() to specify that
- * the data directory should be changed.
- */
-#ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
-#  define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
-#endif
-
-/*
- * The value used with sqlite3_win32_set_directory() to specify that
- * the temporary directory should be changed.
- */
-#ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
-#  define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
-#endif
-
-/*
- * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
- * various Win32 API heap functions instead of our own.
- */
-#ifdef SQLITE_WIN32_MALLOC
-
-/*
- * If this is non-zero, an isolated heap will be created by the native Win32
- * allocator subsystem; otherwise, the default process heap will be used.  This
- * setting has no effect when compiling for WinRT.  By default, this is enabled
- * and an isolated heap will be created to store all allocated data.
- *
- ******************************************************************************
- * WARNING: It is important to note that when this setting is non-zero and the
- *          winMemShutdown function is called (e.g. by the sqlite3_shutdown
- *          function), all data that was allocated using the isolated heap will
- *          be freed immediately and any attempt to access any of that freed
- *          data will almost certainly result in an immediate access violation.
- ******************************************************************************
- */
-#ifndef SQLITE_WIN32_HEAP_CREATE
-#  define SQLITE_WIN32_HEAP_CREATE    (TRUE)
-#endif
-
-/*
- * The initial size of the Win32-specific heap.  This value may be zero.
- */
-#ifndef SQLITE_WIN32_HEAP_INIT_SIZE
-#  define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_DEFAULT_CACHE_SIZE) * \
-                                       (SQLITE_DEFAULT_PAGE_SIZE) + 4194304)
-#endif
-
-/*
- * The maximum size of the Win32-specific heap.  This value may be zero.
- */
-#ifndef SQLITE_WIN32_HEAP_MAX_SIZE
-#  define SQLITE_WIN32_HEAP_MAX_SIZE  (0)
-#endif
-
-/*
- * The extra flags to use in calls to the Win32 heap APIs.  This value may be
- * zero for the default behavior.
- */
-#ifndef SQLITE_WIN32_HEAP_FLAGS
-#  define SQLITE_WIN32_HEAP_FLAGS     (0)
-#endif
-
-
-/*
-** The winMemData structure stores information required by the Win32-specific
-** sqlite3_mem_methods implementation.
-*/
-typedef struct winMemData winMemData;
-struct winMemData {
-#ifndef NDEBUG
-  u32 magic;    /* Magic number to detect structure corruption. */
-#endif
-  HANDLE hHeap; /* The handle to our heap. */
-  BOOL bOwned;  /* Do we own the heap (i.e. destroy it on shutdown)? */
-};
-
-#ifndef NDEBUG
-#define WINMEM_MAGIC     0x42b2830b
-#endif
-
-static struct winMemData win_mem_data = {
-#ifndef NDEBUG
-  WINMEM_MAGIC,
-#endif
-  NULL, FALSE
-};
-
-#ifndef NDEBUG
-#define winMemAssertMagic() assert( win_mem_data.magic==WINMEM_MAGIC )
-#else
-#define winMemAssertMagic()
-#endif
-
-#define winMemGetHeap() win_mem_data.hHeap
-
-static void *winMemMalloc(int nBytes);
-static void winMemFree(void *pPrior);
-static void *winMemRealloc(void *pPrior, int nBytes);
-static int winMemSize(void *p);
-static int winMemRoundup(int n);
-static int winMemInit(void *pAppData);
-static void winMemShutdown(void *pAppData);
-
-SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void);
-#endif /* SQLITE_WIN32_MALLOC */
-
-/*
-** The following variable is (normally) set once and never changes
-** thereafter.  It records whether the operating system is Win9x
-** or WinNT.
-**
-** 0:   Operating system unknown.
-** 1:   Operating system is Win9x.
-** 2:   Operating system is WinNT.
-**
-** In order to facilitate testing on a WinNT system, the test fixture
-** can manually set this value to 1 to emulate Win98 behavior.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_os_type = 0;
-#elif !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
-      defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_HAS_WIDE)
-static int sqlite3_os_type = 0;
-#endif
-
-#ifndef SYSCALL
-#  define SYSCALL sqlite3_syscall_ptr
-#endif
-
-/*
-** This function is not available on Windows CE or WinRT.
- */
-
-#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
-#  define osAreFileApisANSI()       1
-#endif
-
-/*
-** Many system calls are accessed through pointer-to-functions so that
-** they may be overridden at runtime to facilitate fault injection during
-** testing and sandboxing.  The following array holds the names and pointers
-** to all overrideable system calls.
-*/
-static struct win_syscall {
-  const char *zName;            /* Name of the system call */
-  sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
-  sqlite3_syscall_ptr pDefault; /* Default value */
-} aSyscall[] = {
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
-  { "AreFileApisANSI",         (SYSCALL)AreFileApisANSI,         0 },
-#else
-  { "AreFileApisANSI",         (SYSCALL)0,                       0 },
-#endif
-
-#ifndef osAreFileApisANSI
-#define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
-#endif
-
-#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
-  { "CharLowerW",              (SYSCALL)CharLowerW,              0 },
-#else
-  { "CharLowerW",              (SYSCALL)0,                       0 },
-#endif
-
-#define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
-
-#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
-  { "CharUpperW",              (SYSCALL)CharUpperW,              0 },
-#else
-  { "CharUpperW",              (SYSCALL)0,                       0 },
-#endif
-
-#define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
-
-  { "CloseHandle",             (SYSCALL)CloseHandle,             0 },
-
-#define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "CreateFileA",             (SYSCALL)CreateFileA,             0 },
-#else
-  { "CreateFileA",             (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
-        LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "CreateFileW",             (SYSCALL)CreateFileW,             0 },
-#else
-  { "CreateFileW",             (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
-        LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
-
-#if (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
-        !defined(SQLITE_OMIT_WAL))
-  { "CreateFileMappingA",      (SYSCALL)CreateFileMappingA,      0 },
-#else
-  { "CreateFileMappingA",      (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
-        DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
-
-#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
-        !defined(SQLITE_OMIT_WAL))
-  { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
-#else
-  { "CreateFileMappingW",      (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
-        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "CreateMutexW",            (SYSCALL)CreateMutexW,            0 },
-#else
-  { "CreateMutexW",            (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
-        LPCWSTR))aSyscall[8].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "DeleteFileA",             (SYSCALL)DeleteFileA,             0 },
-#else
-  { "DeleteFileA",             (SYSCALL)0,                       0 },
-#endif
-
-#define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  { "DeleteFileW",             (SYSCALL)DeleteFileW,             0 },
-#else
-  { "DeleteFileW",             (SYSCALL)0,                       0 },
-#endif
-
-#define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
-
-#if SQLITE_OS_WINCE
-  { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
-#else
-  { "FileTimeToLocalFileTime", (SYSCALL)0,                       0 },
-#endif
-
-#define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
-        LPFILETIME))aSyscall[11].pCurrent)
-
-#if SQLITE_OS_WINCE
-  { "FileTimeToSystemTime",    (SYSCALL)FileTimeToSystemTime,    0 },
-#else
-  { "FileTimeToSystemTime",    (SYSCALL)0,                       0 },
-#endif
-
-#define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
-        LPSYSTEMTIME))aSyscall[12].pCurrent)
-
-  { "FlushFileBuffers",        (SYSCALL)FlushFileBuffers,        0 },
-
-#define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "FormatMessageA",          (SYSCALL)FormatMessageA,          0 },
-#else
-  { "FormatMessageA",          (SYSCALL)0,                       0 },
-#endif
-
-#define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
-        DWORD,va_list*))aSyscall[14].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  { "FormatMessageW",          (SYSCALL)FormatMessageW,          0 },
-#else
-  { "FormatMessageW",          (SYSCALL)0,                       0 },
-#endif
-
-#define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
-        DWORD,va_list*))aSyscall[15].pCurrent)
-
-#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
-  { "FreeLibrary",             (SYSCALL)FreeLibrary,             0 },
-#else
-  { "FreeLibrary",             (SYSCALL)0,                       0 },
-#endif
-
-#define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
-
-  { "GetCurrentProcessId",     (SYSCALL)GetCurrentProcessId,     0 },
-
-#define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
-
-#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
-  { "GetDiskFreeSpaceA",       (SYSCALL)GetDiskFreeSpaceA,       0 },
-#else
-  { "GetDiskFreeSpaceA",       (SYSCALL)0,                       0 },
-#endif
-
-#define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
-        LPDWORD))aSyscall[18].pCurrent)
-
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetDiskFreeSpaceW",       (SYSCALL)GetDiskFreeSpaceW,       0 },
-#else
-  { "GetDiskFreeSpaceW",       (SYSCALL)0,                       0 },
-#endif
-
-#define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
-        LPDWORD))aSyscall[19].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "GetFileAttributesA",      (SYSCALL)GetFileAttributesA,      0 },
-#else
-  { "GetFileAttributesA",      (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetFileAttributesW",      (SYSCALL)GetFileAttributesW,      0 },
-#else
-  { "GetFileAttributesW",      (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetFileAttributesExW",    (SYSCALL)GetFileAttributesExW,    0 },
-#else
-  { "GetFileAttributesExW",    (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
-        LPVOID))aSyscall[22].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "GetFileSize",             (SYSCALL)GetFileSize,             0 },
-#else
-  { "GetFileSize",             (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
-
-#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
-  { "GetFullPathNameA",        (SYSCALL)GetFullPathNameA,        0 },
-#else
-  { "GetFullPathNameA",        (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
-        LPSTR*))aSyscall[24].pCurrent)
-
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetFullPathNameW",        (SYSCALL)GetFullPathNameW,        0 },
-#else
-  { "GetFullPathNameW",        (SYSCALL)0,                       0 },
-#endif
-
-#define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
-        LPWSTR*))aSyscall[25].pCurrent)
-
-  { "GetLastError",            (SYSCALL)GetLastError,            0 },
-
-#define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
-
-#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
-#if SQLITE_OS_WINCE
-  /* The GetProcAddressA() routine is only available on Windows CE. */
-  { "GetProcAddressA",         (SYSCALL)GetProcAddressA,         0 },
-#else
-  /* All other Windows platforms expect GetProcAddress() to take
-  ** an ANSI string regardless of the _UNICODE setting */
-  { "GetProcAddressA",         (SYSCALL)GetProcAddress,          0 },
-#endif
-#else
-  { "GetProcAddressA",         (SYSCALL)0,                       0 },
-#endif
-
-#define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
-        LPCSTR))aSyscall[27].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "GetSystemInfo",           (SYSCALL)GetSystemInfo,           0 },
-#else
-  { "GetSystemInfo",           (SYSCALL)0,                       0 },
-#endif
-
-#define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
-
-  { "GetSystemTime",           (SYSCALL)GetSystemTime,           0 },
-
-#define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
-
-#if !SQLITE_OS_WINCE
-  { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
-#else
-  { "GetSystemTimeAsFileTime", (SYSCALL)0,                       0 },
-#endif
-
-#define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
-        LPFILETIME))aSyscall[30].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "GetTempPathA",            (SYSCALL)GetTempPathA,            0 },
-#else
-  { "GetTempPathA",            (SYSCALL)0,                       0 },
-#endif
-
-#define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetTempPathW",            (SYSCALL)GetTempPathW,            0 },
-#else
-  { "GetTempPathW",            (SYSCALL)0,                       0 },
-#endif
-
-#define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "GetTickCount",            (SYSCALL)GetTickCount,            0 },
-#else
-  { "GetTickCount",            (SYSCALL)0,                       0 },
-#endif
-
-#define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
-#else
-  { "GetVersionExA",           (SYSCALL)0,                       0 },
-#endif
-
-#define osGetVersionExA ((BOOL(WINAPI*)( \
-        LPOSVERSIONINFOA))aSyscall[34].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
-  { "GetVersionExW",           (SYSCALL)GetVersionExW,           0 },
-#else
-  { "GetVersionExW",           (SYSCALL)0,                       0 },
-#endif
-
-#define osGetVersionExW ((BOOL(WINAPI*)( \
-        LPOSVERSIONINFOW))aSyscall[35].pCurrent)
-
-  { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },
-
-#define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
-        SIZE_T))aSyscall[36].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
-#else
-  { "HeapCreate",              (SYSCALL)0,                       0 },
-#endif
-
-#define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
-        SIZE_T))aSyscall[37].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
-#else
-  { "HeapDestroy",             (SYSCALL)0,                       0 },
-#endif
-
-#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
-
-  { "HeapFree",                (SYSCALL)HeapFree,                0 },
-
-#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
-
-  { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },
-
-#define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
-        SIZE_T))aSyscall[40].pCurrent)
-
-  { "HeapSize",                (SYSCALL)HeapSize,                0 },
-
-#define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
-        LPCVOID))aSyscall[41].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
-#else
-  { "HeapValidate",            (SYSCALL)0,                       0 },
-#endif
-
-#define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
-        LPCVOID))aSyscall[42].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
-  { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
-#else
-  { "LoadLibraryA",            (SYSCALL)0,                       0 },
-#endif
-
-#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[43].pCurrent)
-
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
-        !defined(SQLITE_OMIT_LOAD_EXTENSION)
-  { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
-#else
-  { "LoadLibraryW",            (SYSCALL)0,                       0 },
-#endif
-
-#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[44].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "LocalFree",               (SYSCALL)LocalFree,               0 },
-#else
-  { "LocalFree",               (SYSCALL)0,                       0 },
-#endif
-
-#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[45].pCurrent)
-
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
-  { "LockFile",                (SYSCALL)LockFile,                0 },
-#else
-  { "LockFile",                (SYSCALL)0,                       0 },
-#endif
-
-#ifndef osLockFile
-#define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        DWORD))aSyscall[46].pCurrent)
-#endif
-
-#if !SQLITE_OS_WINCE
-  { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
-#else
-  { "LockFileEx",              (SYSCALL)0,                       0 },
-#endif
-
-#ifndef osLockFileEx
-#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
-        LPOVERLAPPED))aSyscall[47].pCurrent)
-#endif
-
-#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
-  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
-#else
-  { "MapViewOfFile",           (SYSCALL)0,                       0 },
-#endif
-
-#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        SIZE_T))aSyscall[48].pCurrent)
-
-  { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },
-
-#define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
-        int))aSyscall[49].pCurrent)
-
-  { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
-
-#define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
-        LARGE_INTEGER*))aSyscall[50].pCurrent)
-
-  { "ReadFile",                (SYSCALL)ReadFile,                0 },
-
-#define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
-        LPOVERLAPPED))aSyscall[51].pCurrent)
-
-  { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },
-
-#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[52].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
-#else
-  { "SetFilePointer",          (SYSCALL)0,                       0 },
-#endif
-
-#define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
-        DWORD))aSyscall[53].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "Sleep",                   (SYSCALL)Sleep,                   0 },
-#else
-  { "Sleep",                   (SYSCALL)0,                       0 },
-#endif
-
-#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[54].pCurrent)
-
-  { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },
-
-#define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
-        LPFILETIME))aSyscall[55].pCurrent)
-
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
-  { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
-#else
-  { "UnlockFile",              (SYSCALL)0,                       0 },
-#endif
-
-#ifndef osUnlockFile
-#define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        DWORD))aSyscall[56].pCurrent)
-#endif
-
-#if !SQLITE_OS_WINCE
-  { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
-#else
-  { "UnlockFileEx",            (SYSCALL)0,                       0 },
-#endif
-
-#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        LPOVERLAPPED))aSyscall[57].pCurrent)
-
-#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
-  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
-#else
-  { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
-#endif
-
-#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[58].pCurrent)
-
-  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },
-
-#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
-        LPCSTR,LPBOOL))aSyscall[59].pCurrent)
-
-  { "WriteFile",               (SYSCALL)WriteFile,               0 },
-
-#define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
-        LPOVERLAPPED))aSyscall[60].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
-#else
-  { "CreateEventExW",          (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
-        DWORD,DWORD))aSyscall[61].pCurrent)
-
-#if !SQLITE_OS_WINRT
-  { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
-#else
-  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
-#endif
-
-#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
-        DWORD))aSyscall[62].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
-#else
-  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
-#endif
-
-#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
-        BOOL))aSyscall[63].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
-#else
-  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
-#endif
-
-#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
-        PLARGE_INTEGER,DWORD))aSyscall[64].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
-#else
-  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
-#endif
-
-#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
-        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[65].pCurrent)
-
-#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
-  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
-#else
-  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
-#endif
-
-#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
-        SIZE_T))aSyscall[66].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
-#else
-  { "CreateFile2",             (SYSCALL)0,                       0 },
-#endif
-
-#define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
-        LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[67].pCurrent)
-
-#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
-  { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
-#else
-  { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
-#endif
-
-#define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
-        DWORD))aSyscall[68].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
-#else
-  { "GetTickCount64",          (SYSCALL)0,                       0 },
-#endif
-
-#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[69].pCurrent)
-
-#if SQLITE_OS_WINRT
-  { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
-#else
-  { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
-#endif
-
-#define osGetNativeSystemInfo ((VOID(WINAPI*)( \
-        LPSYSTEM_INFO))aSyscall[70].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
-#else
-  { "OutputDebugStringA",      (SYSCALL)0,                       0 },
-#endif
-
-#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[71].pCurrent)
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
-#else
-  { "OutputDebugStringW",      (SYSCALL)0,                       0 },
-#endif
-
-#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[72].pCurrent)
-
-  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },
-
-#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[73].pCurrent)
-
-#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
-  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
+    /*
+    ** At this point, variables are initialized as follows:
+    **
+    **   flag_alternateform          TRUE if a '#' is present.
+    **   flag_altform2               TRUE if a '!' is present.
+    **   flag_plussign               TRUE if a '+' is present.
+    **   flag_leftjustify            TRUE if a '-' is present or if the
+    **                               field width was negative.
+    **   flag_zeropad                TRUE if the width began with 0.
+    **   flag_long                   TRUE if the letter 'l' (ell) prefixed
+    **                               the conversion character.
+    **   flag_longlong               TRUE if the letter 'll' (ell ell) prefixed
+    **                               the conversion character.
+    **   flag_blanksign              TRUE if a ' ' is present.
+    **   width                       The specified field width.  This is
+    **                               always non-negative.  Zero is the default.
+    **   precision                   The specified precision.  The default
+    **                               is -1.
+    **   xtype                       The class of the conversion.
+    **   infop                       Pointer to the appropriate info struct.
+    */
+    switch( xtype ){
+      case etPOINTER:
+        flag_longlong = sizeof(char*)==sizeof(i64);
+        flag_long = sizeof(char*)==sizeof(long int);
+        /* Fall through into the next case */
+      case etORDINAL:
+      case etRADIX:
+        if( infop->flags & FLAG_SIGNED ){
+          i64 v;
+          if( flag_longlong ){
+            v = va_arg(ap,i64);
+          }else if( flag_long ){
+            v = va_arg(ap,long int);
+          }else{
+            v = va_arg(ap,int);
+          }
+          if( v<0 ){
+            if( v==SMALLEST_INT64 ){
+              longvalue = ((u64)1)<<63;
+            }else{
+              longvalue = -v;
+            }
+            prefix = '-';
+          }else{
+            longvalue = v;
+            if( flag_plussign )        prefix = '+';
+            else if( flag_blanksign )  prefix = ' ';
+            else                       prefix = 0;
+          }
+        }else{
+          if( flag_longlong ){
+            longvalue = va_arg(ap,u64);
+          }else if( flag_long ){
+            longvalue = va_arg(ap,unsigned long int);
+          }else{
+            longvalue = va_arg(ap,unsigned int);
+          }
+          prefix = 0;
+        }
+        if( longvalue==0 ) flag_alternateform = 0;
+        if( flag_zeropad && precision<width-(prefix!=0) ){
+          precision = width-(prefix!=0);
+        }
+        if( precision<etBUFSIZE-10 ){
+          nOut = etBUFSIZE;
+          zOut = buf;
+        }else{
+          nOut = precision + 10;
+          zOut = zExtra = sqlite3Malloc( nOut );
+          if( zOut==0 ){
+            pAccum->accError = STRACCUM_NOMEM;
+            return;
+          }
+        }
+        bufpt = &zOut[nOut-1];
+        if( xtype==etORDINAL ){
+          static const char zOrd[] = "thstndrd";
+          int x = (int)(longvalue % 10);
+          if( x>=4 || (longvalue/10)%10==1 ){
+            x = 0;
+          }
+          *(--bufpt) = zOrd[x*2+1];
+          *(--bufpt) = zOrd[x*2];
+        }
+        {
+          register const char *cset;      /* Use registers for speed */
+          register int base;
+          cset = &aDigits[infop->charset];
+          base = infop->base;
+          do{                                           /* Convert to ascii */
+            *(--bufpt) = cset[longvalue%base];
+            longvalue = longvalue/base;
+          }while( longvalue>0 );
+        }
+        length = (int)(&zOut[nOut-1]-bufpt);
+        for(idx=precision-length; idx>0; idx--){
+          *(--bufpt) = '0';                             /* Zero pad */
+        }
+        if( prefix ) *(--bufpt) = prefix;               /* Add sign */
+        if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
+          const char *pre;
+          char x;
+          pre = &aPrefix[infop->prefix];
+          for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
+        }
+        length = (int)(&zOut[nOut-1]-bufpt);
+        break;
+      case etFLOAT:
+      case etEXP:
+      case etGENERIC:
+        realvalue = va_arg(ap,double);
+#ifdef SQLITE_OMIT_FLOATING_POINT
+        length = 0;
 #else
-  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
-#endif
-
-#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
-        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[74].pCurrent)
-
-}; /* End of the overrideable system calls */
+        if( precision<0 ) precision = 6;         /* Set default precision */
+        if( realvalue<0.0 ){
+          realvalue = -realvalue;
+          prefix = '-';
+        }else{
+          if( flag_plussign )          prefix = '+';
+          else if( flag_blanksign )    prefix = ' ';
+          else                         prefix = 0;
+        }
+        if( xtype==etGENERIC && precision>0 ) precision--;
+        for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
+        if( xtype==etFLOAT ) realvalue += rounder;
+        /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
+        exp = 0;
+        if( sqlite3IsNaN((double)realvalue) ){
+          bufpt = "NaN";
+          length = 3;
+          break;
+        }
+        if( realvalue>0.0 ){
+          LONGDOUBLE_TYPE scale = 1.0;
+          while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
+          while( realvalue>=1e64*scale && exp<=350 ){ scale *= 1e64; exp+=64; }
+          while( realvalue>=1e8*scale && exp<=350 ){ scale *= 1e8; exp+=8; }
+          while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
+          realvalue /= scale;
+          while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
+          while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
+          if( exp>350 ){
+            if( prefix=='-' ){
+              bufpt = "-Inf";
+            }else if( prefix=='+' ){
+              bufpt = "+Inf";
+            }else{
+              bufpt = "Inf";
+            }
+            length = sqlite3Strlen30(bufpt);
+            break;
+          }
+        }
+        bufpt = buf;
+        /*
+        ** If the field type is etGENERIC, then convert to either etEXP
+        ** or etFLOAT, as appropriate.
+        */
+        if( xtype!=etFLOAT ){
+          realvalue += rounder;
+          if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
+        }
+        if( xtype==etGENERIC ){
+          flag_rtz = !flag_alternateform;
+          if( exp<-4 || exp>precision ){
+            xtype = etEXP;
+          }else{
+            precision = precision - exp;
+            xtype = etFLOAT;
+          }
+        }else{
+          flag_rtz = flag_altform2;
+        }
+        if( xtype==etEXP ){
+          e2 = 0;
+        }else{
+          e2 = exp;
+        }
+        if( MAX(e2,0)+precision+width > etBUFSIZE - 15 ){
+          bufpt = zExtra = sqlite3Malloc( MAX(e2,0)+precision+width+15 );
+          if( bufpt==0 ){
+            pAccum->accError = STRACCUM_NOMEM;
+            return;
+          }
+        }
+        zOut = bufpt;
+        nsd = 16 + flag_altform2*10;
+        flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
+        /* The sign in front of the number */
+        if( prefix ){
+          *(bufpt++) = prefix;
+        }
+        /* Digits prior to the decimal point */
+        if( e2<0 ){
+          *(bufpt++) = '0';
+        }else{
+          for(; e2>=0; e2--){
+            *(bufpt++) = et_getdigit(&realvalue,&nsd);
+          }
+        }
+        /* The decimal point */
+        if( flag_dp ){
+          *(bufpt++) = '.';
+        }
+        /* "0" digits after the decimal point but before the first
+        ** significant digit of the number */
+        for(e2++; e2<0; precision--, e2++){
+          assert( precision>0 );
+          *(bufpt++) = '0';
+        }
+        /* Significant digits after the decimal point */
+        while( (precision--)>0 ){
+          *(bufpt++) = et_getdigit(&realvalue,&nsd);
+        }
+        /* Remove trailing zeros and the "." if no digits follow the "." */
+        if( flag_rtz && flag_dp ){
+          while( bufpt[-1]=='0' ) *(--bufpt) = 0;
+          assert( bufpt>zOut );
+          if( bufpt[-1]=='.' ){
+            if( flag_altform2 ){
+              *(bufpt++) = '0';
+            }else{
+              *(--bufpt) = 0;
+            }
+          }
+        }
+        /* Add the "eNNN" suffix */
+        if( xtype==etEXP ){
+          *(bufpt++) = aDigits[infop->charset];
+          if( exp<0 ){
+            *(bufpt++) = '-'; exp = -exp;
+          }else{
+            *(bufpt++) = '+';
+          }
+          if( exp>=100 ){
+            *(bufpt++) = (char)((exp/100)+'0');        /* 100's digit */
+            exp %= 100;
+          }
+          *(bufpt++) = (char)(exp/10+'0');             /* 10's digit */
+          *(bufpt++) = (char)(exp%10+'0');             /* 1's digit */
+        }
+        *bufpt = 0;
 
-/*
-** This is the xSetSystemCall() method of sqlite3_vfs for all of the
-** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
-** system call pointer, or SQLITE_NOTFOUND if there is no configurable
-** system call named zName.
-*/
-static int winSetSystemCall(
-  sqlite3_vfs *pNotUsed,        /* The VFS pointer.  Not used */
-  const char *zName,            /* Name of system call to override */
-  sqlite3_syscall_ptr pNewFunc  /* Pointer to new system call value */
-){
-  unsigned int i;
-  int rc = SQLITE_NOTFOUND;
+        /* The converted number is in buf[] and zero terminated. Output it.
+        ** Note that the number is in the usual order, not reversed as with
+        ** integer conversions. */
+        length = (int)(bufpt-zOut);
+        bufpt = zOut;
 
-  UNUSED_PARAMETER(pNotUsed);
-  if( zName==0 ){
-    /* If no zName is given, restore all system calls to their default
-    ** settings and return NULL
-    */
-    rc = SQLITE_OK;
-    for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-      if( aSyscall[i].pDefault ){
-        aSyscall[i].pCurrent = aSyscall[i].pDefault;
+        /* Special case:  Add leading zeros if the flag_zeropad flag is
+        ** set and we are not left justified */
+        if( flag_zeropad && !flag_leftjustify && length < width){
+          int i;
+          int nPad = width - length;
+          for(i=width; i>=nPad; i--){
+            bufpt[i] = bufpt[i-nPad];
+          }
+          i = prefix!=0;
+          while( nPad-- ) bufpt[i++] = '0';
+          length = width;
+        }
+#endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
+        break;
+      case etSIZE:
+        *(va_arg(ap,int*)) = pAccum->nChar;
+        length = width = 0;
+        break;
+      case etPERCENT:
+        buf[0] = '%';
+        bufpt = buf;
+        length = 1;
+        break;
+      case etCHARX:
+        c = va_arg(ap,int);
+        buf[0] = (char)c;
+        if( precision>=0 ){
+          for(idx=1; idx<precision; idx++) buf[idx] = (char)c;
+          length = precision;
+        }else{
+          length =1;
+        }
+        bufpt = buf;
+        break;
+      case etSTRING:
+      case etDYNSTRING:
+        bufpt = va_arg(ap,char*);
+        if( bufpt==0 ){
+          bufpt = "";
+        }else if( xtype==etDYNSTRING ){
+          zExtra = bufpt;
+        }
+        if( precision>=0 ){
+          for(length=0; length<precision && bufpt[length]; length++){}
+        }else{
+          length = sqlite3Strlen30(bufpt);
+        }
+        break;
+      case etSQLESCAPE:
+      case etSQLESCAPE2:
+      case etSQLESCAPE3: {
+        int i, j, k, n, isnull;
+        int needQuote;
+        char ch;
+        char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
+        char *escarg = va_arg(ap,char*);
+        isnull = escarg==0;
+        if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
+        k = precision;
+        for(i=n=0; k!=0 && (ch=escarg[i])!=0; i++, k--){
+          if( ch==q )  n++;
+        }
+        needQuote = !isnull && xtype==etSQLESCAPE2;
+        n += i + 1 + needQuote*2;
+        if( n>etBUFSIZE ){
+          bufpt = zExtra = sqlite3Malloc( n );
+          if( bufpt==0 ){
+            pAccum->accError = STRACCUM_NOMEM;
+            return;
+          }
+        }else{
+          bufpt = buf;
+        }
+        j = 0;
+        if( needQuote ) bufpt[j++] = q;
+        k = i;
+        for(i=0; i<k; i++){
+          bufpt[j++] = ch = escarg[i];
+          if( ch==q ) bufpt[j++] = ch;
+        }
+        if( needQuote ) bufpt[j++] = q;
+        bufpt[j] = 0;
+        length = j;
+        /* The precision in %q and %Q means how many input characters to
+        ** consume, not the length of the output...
+        ** if( precision>=0 && precision<length ) length = precision; */
+        break;
       }
-    }
-  }else{
-    /* If zName is specified, operate on only the one system call
-    ** specified.
-    */
-    for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-      if( strcmp(zName, aSyscall[i].zName)==0 ){
-        if( aSyscall[i].pDefault==0 ){
-          aSyscall[i].pDefault = aSyscall[i].pCurrent;
+      case etTOKEN: {
+        Token *pToken = va_arg(ap, Token*);
+        if( pToken ){
+          sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
         }
-        rc = SQLITE_OK;
-        if( pNewFunc==0 ) pNewFunc = aSyscall[i].pDefault;
-        aSyscall[i].pCurrent = pNewFunc;
+        length = width = 0;
+        break;
+      }
+      case etSRCLIST: {
+        SrcList *pSrc = va_arg(ap, SrcList*);
+        int k = va_arg(ap, int);
+        struct SrcList_item *pItem = &pSrc->a[k];
+        assert( k>=0 && k<pSrc->nSrc );
+        if( pItem->zDatabase ){
+          sqlite3StrAccumAppend(pAccum, pItem->zDatabase, -1);
+          sqlite3StrAccumAppend(pAccum, ".", 1);
+        }
+        sqlite3StrAccumAppend(pAccum, pItem->zName, -1);
+        length = width = 0;
         break;
       }
+      default: {
+        assert( xtype==etINVALID );
+        return;
+      }
+    }/* End switch over the format type */
+    /*
+    ** The text of the conversion is pointed to by "bufpt" and is
+    ** "length" characters long.  The field width is "width".  Do
+    ** the output.
+    */
+    if( !flag_leftjustify ){
+      register int nspace;
+      nspace = width-length;
+      if( nspace>0 ){
+        sqlite3AppendSpace(pAccum, nspace);
+      }
     }
-  }
-  return rc;
-}
-
-/*
-** Return the value of a system call.  Return NULL if zName is not a
-** recognized system call name.  NULL is also returned if the system call
-** is currently undefined.
-*/
-static sqlite3_syscall_ptr winGetSystemCall(
-  sqlite3_vfs *pNotUsed,
-  const char *zName
-){
-  unsigned int i;
-
-  UNUSED_PARAMETER(pNotUsed);
-  for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
-    if( strcmp(zName, aSyscall[i].zName)==0 ) return aSyscall[i].pCurrent;
-  }
-  return 0;
-}
-
-/*
-** Return the name of the first system call after zName.  If zName==NULL
-** then return the name of the first system call.  Return NULL if zName
-** is the last system call or if zName is not the name of a valid
-** system call.
-*/
-static const char *winNextSystemCall(sqlite3_vfs *p, const char *zName){
-  int i = -1;
-
-  UNUSED_PARAMETER(p);
-  if( zName ){
-    for(i=0; i<ArraySize(aSyscall)-1; i++){
-      if( strcmp(zName, aSyscall[i].zName)==0 ) break;
+    if( length>0 ){
+      sqlite3StrAccumAppend(pAccum, bufpt, length);
     }
-  }
-  for(i++; i<ArraySize(aSyscall); i++){
-    if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
-  }
-  return 0;
-}
+    if( flag_leftjustify ){
+      register int nspace;
+      nspace = width-length;
+      if( nspace>0 ){
+        sqlite3AppendSpace(pAccum, nspace);
+      }
+    }
+    sqlite3_free(zExtra);
+  }/* End for loop over the format string */
+} /* End of function */
 
 /*
-** This function outputs the specified (ANSI) string to the Win32 debugger
-** (if available).
+** Append N bytes of text from z to the StrAccum object.
 */
-
-SQLITE_API void sqlite3_win32_write_debug(const char *zBuf, int nBuf){
-  char zDbgBuf[SQLITE_WIN32_DBG_BUF_SIZE];
-  int nMin = MIN(nBuf, (SQLITE_WIN32_DBG_BUF_SIZE - 1)); /* may be negative. */
-  if( nMin<-1 ) nMin = -1; /* all negative values become -1. */
-  assert( nMin==-1 || nMin==0 || nMin<SQLITE_WIN32_DBG_BUF_SIZE );
-#if defined(SQLITE_WIN32_HAS_ANSI)
-  if( nMin>0 ){
-    memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
-    memcpy(zDbgBuf, zBuf, nMin);
-    osOutputDebugStringA(zDbgBuf);
-  }else{
-    osOutputDebugStringA(zBuf);
-  }
-#elif defined(SQLITE_WIN32_HAS_WIDE)
-  memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
-  if ( osMultiByteToWideChar(
-          osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
-          nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
+SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
+  assert( z!=0 || N==0 );
+  if( p->accError ){
+    testcase(p->accError==STRACCUM_TOOBIG);
+    testcase(p->accError==STRACCUM_NOMEM);
     return;
   }
-  osOutputDebugStringW((LPCWSTR)zDbgBuf);
-#else
-  if( nMin>0 ){
-    memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
-    memcpy(zDbgBuf, zBuf, nMin);
-    fprintf(stderr, "%s", zDbgBuf);
-  }else{
-    fprintf(stderr, "%s", zBuf);
-  }
-#endif
-}
-
-/*
-** The following routine suspends the current thread for at least ms
-** milliseconds.  This is equivalent to the Win32 Sleep() interface.
-*/
-#if SQLITE_OS_WINRT
-static HANDLE sleepObj = NULL;
-#endif
-
-SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds){
-#if SQLITE_OS_WINRT
-  if ( sleepObj==NULL ){
-    sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
-                                SYNCHRONIZE);
-  }
-  assert( sleepObj!=NULL );
-  osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
-#else
-  osSleep(milliseconds);
-#endif
-}
-
-/*
-** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
-** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
-**
-** Here is an interesting observation:  Win95, Win98, and WinME lack
-** the LockFileEx() API.  But we can still statically link against that
-** API as long as we don't call it when running Win95/98/ME.  A call to
-** this routine is used to determine if the host is Win95/98/ME or
-** WinNT/2K/XP so that we will know whether or not we can safely call
-** the LockFileEx() API.
-*/
-#ifndef NTDDI_WIN8
-#  define NTDDI_WIN8                        0x06020000
-#endif
-
-#if SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
-# define osIsNT()  (1)
-#elif !defined(SQLITE_WIN32_HAS_WIDE)
-# define osIsNT()  (0)
-#else
-  static int osIsNT(void){
-    if( sqlite3_os_type==0 ){
-#if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WIN8
-      OSVERSIONINFOW sInfo;
-      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
-      osGetVersionExW(&sInfo);
-#else
-      OSVERSIONINFOA sInfo;
-      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
-      osGetVersionExA(&sInfo);
-#endif
-      sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
-    }
-    return sqlite3_os_type==2;
-  }
-#endif
-
-#ifdef SQLITE_WIN32_MALLOC
-/*
-** Allocate nBytes of memory.
-*/
-static void *winMemMalloc(int nBytes){
-  HANDLE hHeap;
-  void *p;
-
-  winMemAssertMagic();
-  hHeap = winMemGetHeap();
-  assert( hHeap!=0 );
-  assert( hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
-#endif
-  assert( nBytes>=0 );
-  p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
-  if( !p ){
-    sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
-                nBytes, osGetLastError(), (void*)hHeap);
+  assert( p->zText!=0 || p->nChar==0 );
+  if( N<=0 ){
+    if( N==0 || z[0]==0 ) return;
+    N = sqlite3Strlen30(z);
   }
-  return p;
-}
-
-/*
-** Free memory.
-*/
-static void winMemFree(void *pPrior){
-  HANDLE hHeap;
-
-  winMemAssertMagic();
-  hHeap = winMemGetHeap();
-  assert( hHeap!=0 );
-  assert( hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
-#endif
-  if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
-  if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
-    sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
-                pPrior, osGetLastError(), (void*)hHeap);
+  if( p->nChar+N >= p->nAlloc ){
+    char *zNew;
+    if( !p->useMalloc ){
+      p->accError = STRACCUM_TOOBIG;
+      N = p->nAlloc - p->nChar - 1;
+      if( N<=0 ){
+        return;
+      }
+    }else{
+      char *zOld = (p->zText==p->zBase ? 0 : p->zText);
+      i64 szNew = p->nChar;
+      szNew += N + 1;
+      if( szNew > p->mxAlloc ){
+        sqlite3StrAccumReset(p);
+        p->accError = STRACCUM_TOOBIG;
+        return;
+      }else{
+        p->nAlloc = (int)szNew;
+      }
+      if( p->useMalloc==1 ){
+        zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
+      }else{
+        zNew = sqlite3_realloc(zOld, p->nAlloc);
+      }
+      if( zNew ){
+        if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
+        p->zText = zNew;
+      }else{
+        p->accError = STRACCUM_NOMEM;
+        sqlite3StrAccumReset(p);
+        return;
+      }
+    }
   }
+  assert( p->zText );
+  memcpy(&p->zText[p->nChar], z, N);
+  p->nChar += N;
 }
 
 /*
-** Change the size of an existing memory allocation
+** Finish off a string by making sure it is zero-terminated.
+** Return a pointer to the resulting string.  Return a NULL
+** pointer if any kind of error was encountered.
 */
-static void *winMemRealloc(void *pPrior, int nBytes){
-  HANDLE hHeap;
-  void *p;
-
-  winMemAssertMagic();
-  hHeap = winMemGetHeap();
-  assert( hHeap!=0 );
-  assert( hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
-#endif
-  assert( nBytes>=0 );
-  if( !pPrior ){
-    p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
-  }else{
-    p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
-  }
-  if( !p ){
-    sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
-                pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
-                (void*)hHeap);
+SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
+  if( p->zText ){
+    p->zText[p->nChar] = 0;
+    if( p->useMalloc && p->zText==p->zBase ){
+      if( p->useMalloc==1 ){
+        p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+      }else{
+        p->zText = sqlite3_malloc(p->nChar+1);
+      }
+      if( p->zText ){
+        memcpy(p->zText, p->zBase, p->nChar+1);
+      }else{
+        p->accError = STRACCUM_NOMEM;
+      }
+    }
   }
-  return p;
+  return p->zText;
 }
 
 /*
-** Return the size of an outstanding allocation, in bytes.
+** Reset an StrAccum string.  Reclaim all malloced memory.
 */
-static int winMemSize(void *p){
-  HANDLE hHeap;
-  SIZE_T n;
-
-  winMemAssertMagic();
-  hHeap = winMemGetHeap();
-  assert( hHeap!=0 );
-  assert( hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
-#endif
-  if( !p ) return 0;
-  n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
-  if( n==(SIZE_T)-1 ){
-    sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
-                p, osGetLastError(), (void*)hHeap);
-    return 0;
+SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
+  if( p->zText!=p->zBase ){
+    if( p->useMalloc==1 ){
+      sqlite3DbFree(p->db, p->zText);
+    }else{
+      sqlite3_free(p->zText);
+    }
   }
-  return (int)n;
+  p->zText = 0;
 }
 
 /*
-** Round up a request size to the next valid allocation size.
+** Initialize a string accumulator
 */
-static int winMemRoundup(int n){
-  return n;
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
+  p->zText = p->zBase = zBase;
+  p->db = 0;
+  p->nChar = 0;
+  p->nAlloc = n;
+  p->mxAlloc = mx;
+  p->useMalloc = 1;
+  p->accError = 0;
 }
 
 /*
-** Initialize this module.
+** Print into memory obtained from sqliteMalloc().  Use the internal
+** %-conversion extensions.
 */
-static int winMemInit(void *pAppData){
-  winMemData *pWinMemData = (winMemData *)pAppData;
-
-  if( !pWinMemData ) return SQLITE_ERROR;
-  assert( pWinMemData->magic==WINMEM_MAGIC );
-
-#if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
-  if( !pWinMemData->hHeap ){
-    pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
-                                      SQLITE_WIN32_HEAP_INIT_SIZE,
-                                      SQLITE_WIN32_HEAP_MAX_SIZE);
-    if( !pWinMemData->hHeap ){
-      sqlite3_log(SQLITE_NOMEM,
-          "failed to HeapCreate (%lu), flags=%u, initSize=%u, maxSize=%u",
-          osGetLastError(), SQLITE_WIN32_HEAP_FLAGS,
-          SQLITE_WIN32_HEAP_INIT_SIZE, SQLITE_WIN32_HEAP_MAX_SIZE);
-      return SQLITE_NOMEM;
-    }
-    pWinMemData->bOwned = TRUE;
-    assert( pWinMemData->bOwned );
-  }
-#else
-  pWinMemData->hHeap = osGetProcessHeap();
-  if( !pWinMemData->hHeap ){
-    sqlite3_log(SQLITE_NOMEM,
-        "failed to GetProcessHeap (%lu)", osGetLastError());
-    return SQLITE_NOMEM;
+SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
+  char *z;
+  char zBase[SQLITE_PRINT_BUF_SIZE];
+  StrAccum acc;
+  assert( db!=0 );
+  sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
+                      db->aLimit[SQLITE_LIMIT_LENGTH]);
+  acc.db = db;
+  sqlite3VXPrintf(&acc, 1, zFormat, ap);
+  z = sqlite3StrAccumFinish(&acc);
+  if( acc.accError==STRACCUM_NOMEM ){
+    db->mallocFailed = 1;
   }
-  pWinMemData->bOwned = FALSE;
-  assert( !pWinMemData->bOwned );
-#endif
-  assert( pWinMemData->hHeap!=0 );
-  assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-  assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
-#endif
-  return SQLITE_OK;
+  return z;
 }
 
 /*
-** Deinitialize this module.
+** Print into memory obtained from sqliteMalloc().  Use the internal
+** %-conversion extensions.
 */
-static void winMemShutdown(void *pAppData){
-  winMemData *pWinMemData = (winMemData *)pAppData;
-
-  if( !pWinMemData ) return;
-  if( pWinMemData->hHeap ){
-    assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
-    assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
-#endif
-    if( pWinMemData->bOwned ){
-      if( !osHeapDestroy(pWinMemData->hHeap) ){
-        sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
-                    osGetLastError(), (void*)pWinMemData->hHeap);
-      }
-      pWinMemData->bOwned = FALSE;
-    }
-    pWinMemData->hHeap = NULL;
-  }
+SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
+  va_list ap;
+  char *z;
+  va_start(ap, zFormat);
+  z = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  return z;
 }
 
 /*
-** Populate the low-level memory allocation function pointers in
-** sqlite3GlobalConfig.m with pointers to the routines in this file. The
-** arguments specify the block of memory to manage.
+** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
+** the string and before returnning.  This routine is intended to be used
+** to modify an existing string.  For example:
 **
-** This routine is only called by sqlite3_config(), and therefore
-** is not required to be threadsafe (it is not).
-*/
-SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void){
-  static const sqlite3_mem_methods winMemMethods = {
-    winMemMalloc,
-    winMemFree,
-    winMemRealloc,
-    winMemSize,
-    winMemRoundup,
-    winMemInit,
-    winMemShutdown,
-    &win_mem_data
-  };
-  return &winMemMethods;
-}
-
-SQLITE_PRIVATE void sqlite3MemSetDefault(void){
-  sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
-}
-#endif /* SQLITE_WIN32_MALLOC */
-
-/*
-** Convert a UTF-8 string to Microsoft Unicode (UTF-16?). 
+**       x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
 **
-** Space to hold the returned string is obtained from malloc.
 */
-static LPWSTR winUtf8ToUnicode(const char *zFilename){
-  int nChar;
-  LPWSTR zWideFilename;
-
-  nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
-  if( nChar==0 ){
-    return 0;
-  }
-  zWideFilename = sqlite3MallocZero( nChar*sizeof(zWideFilename[0]) );
-  if( zWideFilename==0 ){
-    return 0;
-  }
-  nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename,
-                                nChar);
-  if( nChar==0 ){
-    sqlite3_free(zWideFilename);
-    zWideFilename = 0;
-  }
-  return zWideFilename;
+SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
+  va_list ap;
+  char *z;
+  va_start(ap, zFormat);
+  z = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  sqlite3DbFree(db, zStr);
+  return z;
 }
 
 /*
-** Convert Microsoft Unicode to UTF-8.  Space to hold the returned string is
-** obtained from sqlite3_malloc().
+** Print into memory obtained from sqlite3_malloc().  Omit the internal
+** %-conversion extensions.
 */
-static char *winUnicodeToUtf8(LPCWSTR zWideFilename){
-  int nByte;
-  char *zFilename;
-
-  nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
-  if( nByte == 0 ){
-    return 0;
-  }
-  zFilename = sqlite3MallocZero( nByte );
-  if( zFilename==0 ){
-    return 0;
-  }
-  nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
-                                0, 0);
-  if( nByte == 0 ){
-    sqlite3_free(zFilename);
-    zFilename = 0;
-  }
-  return zFilename;
+SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
+  char *z;
+  char zBase[SQLITE_PRINT_BUF_SIZE];
+  StrAccum acc;
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
+  acc.useMalloc = 2;
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
+  z = sqlite3StrAccumFinish(&acc);
+  return z;
 }
 
 /*
-** Convert an ANSI string to Microsoft Unicode, based on the
-** current codepage settings for file apis.
-** 
-** Space to hold the returned string is obtained
-** from sqlite3_malloc.
+** Print into memory obtained from sqlite3_malloc()().  Omit the internal
+** %-conversion extensions.
 */
-static LPWSTR winMbcsToUnicode(const char *zFilename){
-  int nByte;
-  LPWSTR zMbcsFilename;
-  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
-
-  nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
-                                0)*sizeof(WCHAR);
-  if( nByte==0 ){
-    return 0;
-  }
-  zMbcsFilename = sqlite3MallocZero( nByte*sizeof(zMbcsFilename[0]) );
-  if( zMbcsFilename==0 ){
-    return 0;
-  }
-  nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename,
-                                nByte);
-  if( nByte==0 ){
-    sqlite3_free(zMbcsFilename);
-    zMbcsFilename = 0;
-  }
-  return zMbcsFilename;
+SQLITE_API char *sqlite3_mprintf(const char *zFormat, ...){
+  va_list ap;
+  char *z;
+#ifndef SQLITE_OMIT_AUTOINIT
+  if( sqlite3_initialize() ) return 0;
+#endif
+  va_start(ap, zFormat);
+  z = sqlite3_vmprintf(zFormat, ap);
+  va_end(ap);
+  return z;
 }
 
 /*
-** Convert Microsoft Unicode to multi-byte character string, based on the
-** user's ANSI codepage.
+** sqlite3_snprintf() works like snprintf() except that it ignores the
+** current locale settings.  This is important for SQLite because we
+** are not able to use a "," as the decimal point in place of "." as
+** specified by some locales.
+**
+** Oops:  The first two arguments of sqlite3_snprintf() are backwards
+** from the snprintf() standard.  Unfortunately, it is too late to change
+** this without breaking compatibility, so we just have to live with the
+** mistake.
 **
-** Space to hold the returned string is obtained from
-** sqlite3_malloc().
+** sqlite3_vsnprintf() is the varargs version.
 */
-static char *winUnicodeToMbcs(LPCWSTR zWideFilename){
-  int nByte;
-  char *zFilename;
-  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
-
-  nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
-  if( nByte == 0 ){
-    return 0;
-  }
-  zFilename = sqlite3MallocZero( nByte );
-  if( zFilename==0 ){
-    return 0;
-  }
-  nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename,
-                                nByte, 0, 0);
-  if( nByte == 0 ){
-    sqlite3_free(zFilename);
-    zFilename = 0;
-  }
-  return zFilename;
+SQLITE_API char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
+  StrAccum acc;
+  if( n<=0 ) return zBuf;
+  sqlite3StrAccumInit(&acc, zBuf, n, 0);
+  acc.useMalloc = 0;
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
+  return sqlite3StrAccumFinish(&acc);
+}
+SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
+  char *z;
+  va_list ap;
+  va_start(ap,zFormat);
+  z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
+  va_end(ap);
+  return z;
 }
 
 /*
-** Convert multibyte character string to UTF-8.  Space to hold the
-** returned string is obtained from sqlite3_malloc().
+** This is the routine that actually formats the sqlite3_log() message.
+** We house it in a separate routine from sqlite3_log() to avoid using
+** stack space on small-stack systems when logging is disabled.
+**
+** sqlite3_log() must render into a static buffer.  It cannot dynamically
+** allocate memory because it might be called while the memory allocator
+** mutex is held.
 */
-SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
-  char *zFilenameUtf8;
-  LPWSTR zTmpWide;
+static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
+  StrAccum acc;                          /* String accumulator */
+  char zMsg[SQLITE_PRINT_BUF_SIZE*3];    /* Complete log message */
 
-  zTmpWide = winMbcsToUnicode(zFilename);
-  if( zTmpWide==0 ){
-    return 0;
-  }
-  zFilenameUtf8 = winUnicodeToUtf8(zTmpWide);
-  sqlite3_free(zTmpWide);
-  return zFilenameUtf8;
+  sqlite3StrAccumInit(&acc, zMsg, sizeof(zMsg), 0);
+  acc.useMalloc = 0;
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
+  sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
+                           sqlite3StrAccumFinish(&acc));
 }
 
 /*
-** Convert UTF-8 to multibyte character string.  Space to hold the 
-** returned string is obtained from sqlite3_malloc().
+** Format and write a message to the log if logging is enabled.
 */
-SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
-  char *zFilenameMbcs;
-  LPWSTR zTmpWide;
-
-  zTmpWide = winUtf8ToUnicode(zFilename);
-  if( zTmpWide==0 ){
-    return 0;
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...){
+  va_list ap;                             /* Vararg list */
+  if( sqlite3GlobalConfig.xLog ){
+    va_start(ap, zFormat);
+    renderLogMsg(iErrCode, zFormat, ap);
+    va_end(ap);
   }
-  zFilenameMbcs = winUnicodeToMbcs(zTmpWide);
-  sqlite3_free(zTmpWide);
-  return zFilenameMbcs;
 }
 
+#if defined(SQLITE_DEBUG)
 /*
-** This function sets the data directory or the temporary directory based on
-** the provided arguments.  The type argument must be 1 in order to set the
-** data directory or 2 in order to set the temporary directory.  The zValue
-** argument is the name of the directory to use.  The return value will be
-** SQLITE_OK if successful.
+** A version of printf() that understands %lld.  Used for debugging.
+** The printf() built into some versions of windows does not understand %lld
+** and segfaults if you give it a long long int.
 */
-SQLITE_API int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
-  char **ppDirectory = 0;
-#ifndef SQLITE_OMIT_AUTOINIT
-  int rc = sqlite3_initialize();
-  if( rc ) return rc;
-#endif
-  if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
-    ppDirectory = &sqlite3_data_directory;
-  }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
-    ppDirectory = &sqlite3_temp_directory;
-  }
-  assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
-          || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
-  );
-  assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
-  if( ppDirectory ){
-    char *zValueUtf8 = 0;
-    if( zValue && zValue[0] ){
-      zValueUtf8 = winUnicodeToUtf8(zValue);
-      if ( zValueUtf8==0 ){
-        return SQLITE_NOMEM;
-      }
-    }
-    sqlite3_free(*ppDirectory);
-    *ppDirectory = zValueUtf8;
-    return SQLITE_OK;
-  }
-  return SQLITE_ERROR;
+SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
+  va_list ap;
+  StrAccum acc;
+  char zBuf[500];
+  sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
+  acc.useMalloc = 0;
+  va_start(ap,zFormat);
+  sqlite3VXPrintf(&acc, 0, zFormat, ap);
+  va_end(ap);
+  sqlite3StrAccumFinish(&acc);
+  fprintf(stdout,"%s", zBuf);
+  fflush(stdout);
 }
+#endif
 
+#ifndef SQLITE_OMIT_TRACE
 /*
-** The return value of winGetLastErrorMsg
-** is zero if the error message fits in the buffer, or non-zero
-** otherwise (if the message was truncated).
+** variable-argument wrapper around sqlite3VXPrintf().
 */
-static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
-  /* FormatMessage returns 0 on failure.  Otherwise it
-  ** returns the number of TCHARs written to the output
-  ** buffer, excluding the terminating null char.
-  */
-  DWORD dwLen = 0;
-  char *zOut = 0;
-
-  if( osIsNT() ){
-#if SQLITE_OS_WINRT
-    WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
-    dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
-                             FORMAT_MESSAGE_IGNORE_INSERTS,
-                             NULL,
-                             lastErrno,
-                             0,
-                             zTempWide,
-                             SQLITE_WIN32_MAX_ERRMSG_CHARS,
-                             0);
-#else
-    LPWSTR zTempWide = NULL;
-    dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
-                             FORMAT_MESSAGE_FROM_SYSTEM |
-                             FORMAT_MESSAGE_IGNORE_INSERTS,
-                             NULL,
-                             lastErrno,
-                             0,
-                             (LPWSTR) &zTempWide,
-                             0,
-                             0);
-#endif
-    if( dwLen > 0 ){
-      /* allocate a buffer and convert to UTF8 */
-      sqlite3BeginBenignMalloc();
-      zOut = winUnicodeToUtf8(zTempWide);
-      sqlite3EndBenignMalloc();
-#if !SQLITE_OS_WINRT
-      /* free the system buffer allocated by FormatMessage */
-      osLocalFree(zTempWide);
-#endif
-    }
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    char *zTemp = NULL;
-    dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
-                             FORMAT_MESSAGE_FROM_SYSTEM |
-                             FORMAT_MESSAGE_IGNORE_INSERTS,
-                             NULL,
-                             lastErrno,
-                             0,
-                             (LPSTR) &zTemp,
-                             0,
-                             0);
-    if( dwLen > 0 ){
-      /* allocate a buffer and convert to UTF8 */
-      sqlite3BeginBenignMalloc();
-      zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
-      sqlite3EndBenignMalloc();
-      /* free the system buffer allocated by FormatMessage */
-      osLocalFree(zTemp);
-    }
-  }
-#endif
-  if( 0 == dwLen ){
-    sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
-  }else{
-    /* copy a maximum of nBuf chars to output buffer */
-    sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
-    /* free the UTF8 buffer */
-    sqlite3_free(zOut);
-  }
-  return 0;
+SQLITE_PRIVATE void sqlite3XPrintf(StrAccum *p, const char *zFormat, ...){
+  va_list ap;
+  va_start(ap,zFormat);
+  sqlite3VXPrintf(p, 1, zFormat, ap);
+  va_end(ap);
 }
+#endif
 
+/************** End of printf.c **********************************************/
+/************** Begin file random.c ******************************************/
 /*
+** 2001 September 15
 **
-** This function - winLogErrorAtLine() - is only ever called via the macro
-** winLogError().
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** This routine is invoked after an error occurs in an OS function.
-** It logs a message using sqlite3_log() containing the current value of
-** error code and, if possible, the human-readable equivalent from 
-** FormatMessage.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** The first argument passed to the macro should be the error code that
-** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN). 
-** The two subsequent arguments should be the name of the OS function that
-** failed and the associated file-system path, if any.
+*************************************************************************
+** This file contains code to implement a pseudo-random number
+** generator (PRNG) for SQLite.
+**
+** Random numbers are used by some of the database backends in order
+** to generate random integer keys for tables or random filenames.
 */
-#define winLogError(a,b,c,d)   winLogErrorAtLine(a,b,c,d,__LINE__)
-static int winLogErrorAtLine(
-  int errcode,                    /* SQLite error code */
-  DWORD lastErrno,                /* Win32 last error */
-  const char *zFunc,              /* Name of OS function that failed */
-  const char *zPath,              /* File path associated with error */
-  int iLine                       /* Source line number where error occurred */
-){
-  char zMsg[500];                 /* Human readable error text */
-  int i;                          /* Loop counter */
 
-  zMsg[0] = 0;
-  winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
-  assert( errcode!=SQLITE_OK );
-  if( zPath==0 ) zPath = "";
-  for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
-  zMsg[i] = 0;
-  sqlite3_log(errcode,
-      "os_win.c:%d: (%lu) %s(%s) - %s",
-      iLine, lastErrno, zFunc, zPath, zMsg
-  );
 
-  return errcode;
-}
+/* All threads share a single random number generator.
+** This structure is the current state of the generator.
+*/
+static SQLITE_WSD struct sqlite3PrngType {
+  unsigned char isInit;          /* True if initialized */
+  unsigned char i, j;            /* State variables */
+  unsigned char s[256];          /* State variables */
+} sqlite3Prng;
 
 /*
-** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
-** will be retried following a locking error - probably caused by 
-** antivirus software.  Also the initial delay before the first retry.
-** The delay increases linearly with each retry.
+** Return N random bytes.
 */
-#ifndef SQLITE_WIN32_IOERR_RETRY
-# define SQLITE_WIN32_IOERR_RETRY 10
+SQLITE_API void sqlite3_randomness(int N, void *pBuf){
+  unsigned char t;
+  unsigned char *zBuf = pBuf;
+
+  /* The "wsdPrng" macro will resolve to the pseudo-random number generator
+  ** state vector.  If writable static data is unsupported on the target,
+  ** we have to locate the state vector at run-time.  In the more common
+  ** case where writable static data is supported, wsdPrng can refer directly
+  ** to the "sqlite3Prng" state vector declared above.
+  */
+#ifdef SQLITE_OMIT_WSD
+  struct sqlite3PrngType *p = &GLOBAL(struct sqlite3PrngType, sqlite3Prng);
+# define wsdPrng p[0]
+#else
+# define wsdPrng sqlite3Prng
 #endif
-#ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
-# define SQLITE_WIN32_IOERR_RETRY_DELAY 25
+
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
+  sqlite3_mutex_enter(mutex);
 #endif
-static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
-static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
 
-/*
-** If a ReadFile() or WriteFile() error occurs, invoke this routine
-** to see if it should be retried.  Return TRUE to retry.  Return FALSE
-** to give up with an error.
-*/
-static int winRetryIoerr(int *pnRetry, DWORD *pError){
-  DWORD e = osGetLastError();
-  if( *pnRetry>=winIoerrRetry ){
-    if( pError ){
-      *pError = e;
+  /* Initialize the state of the random number generator once,
+  ** the first time this routine is called.  The seed value does
+  ** not need to contain a lot of randomness since we are not
+  ** trying to do secure encryption or anything like that...
+  **
+  ** Nothing in this file or anywhere else in SQLite does any kind of
+  ** encryption.  The RC4 algorithm is being used as a PRNG (pseudo-random
+  ** number generator) not as an encryption device.
+  */
+  if( !wsdPrng.isInit ){
+    int i;
+    char k[256];
+    wsdPrng.j = 0;
+    wsdPrng.i = 0;
+    sqlite3OsRandomness(sqlite3_vfs_find(0), 256, k);
+    for(i=0; i<256; i++){
+      wsdPrng.s[i] = (u8)i;
     }
-    return 0;
-  }
-  if( e==ERROR_ACCESS_DENIED ||
-      e==ERROR_LOCK_VIOLATION ||
-      e==ERROR_SHARING_VIOLATION ){
-    sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
-    ++*pnRetry;
-    return 1;
-  }
-  if( pError ){
-    *pError = e;
+    for(i=0; i<256; i++){
+      wsdPrng.j += wsdPrng.s[i] + k[i];
+      t = wsdPrng.s[wsdPrng.j];
+      wsdPrng.s[wsdPrng.j] = wsdPrng.s[i];
+      wsdPrng.s[i] = t;
+    }
+    wsdPrng.isInit = 1;
   }
-  return 0;
-}
 
-/*
-** Log a I/O error retry episode.
-*/
-static void winLogIoerr(int nRetry){
-  if( nRetry ){
-    sqlite3_log(SQLITE_IOERR, 
-      "delayed %dms for lock/sharing conflict",
-      winIoerrRetryDelay*nRetry*(nRetry+1)/2
-    );
+  while( N-- ){
+    wsdPrng.i++;
+    t = wsdPrng.s[wsdPrng.i];
+    wsdPrng.j += t;
+    wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
+    wsdPrng.s[wsdPrng.j] = t;
+    t += wsdPrng.s[wsdPrng.i];
+    *(zBuf++) = wsdPrng.s[t];
   }
+  sqlite3_mutex_leave(mutex);
 }
 
-#if SQLITE_OS_WINCE
-/*************************************************************************
-** This section contains code for WinCE only.
-*/
-#if !defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API
+#ifndef SQLITE_OMIT_BUILTIN_TEST
 /*
-** The MSVC CRT on Windows CE may not have a localtime() function.  So
-** create a substitute.
+** For testing purposes, we sometimes want to preserve the state of
+** PRNG and restore the PRNG to its saved state at a later time, or
+** to reset the PRNG to its initial state.  These routines accomplish
+** those tasks.
+**
+** The sqlite3_test_control() interface calls these routines to
+** control the PRNG.
 */
-/* #include <time.h> */
-struct tm *__cdecl localtime(const time_t *t)
-{
-  static struct tm y;
-  FILETIME uTm, lTm;
-  SYSTEMTIME pTm;
-  sqlite3_int64 t64;
-  t64 = *t;
-  t64 = (t64 + 11644473600)*10000000;
-  uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
-  uTm.dwHighDateTime= (DWORD)(t64 >> 32);
-  osFileTimeToLocalFileTime(&uTm,&lTm);
-  osFileTimeToSystemTime(&lTm,&pTm);
-  y.tm_year = pTm.wYear - 1900;
-  y.tm_mon = pTm.wMonth - 1;
-  y.tm_wday = pTm.wDayOfWeek;
-  y.tm_mday = pTm.wDay;
-  y.tm_hour = pTm.wHour;
-  y.tm_min = pTm.wMinute;
-  y.tm_sec = pTm.wSecond;
-  return &y;
+static SQLITE_WSD struct sqlite3PrngType sqlite3SavedPrng;
+SQLITE_PRIVATE void sqlite3PrngSaveState(void){
+  memcpy(
+    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+    sizeof(sqlite3Prng)
+  );
 }
-#endif
-
-#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
+SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
+  memcpy(
+    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+    sizeof(sqlite3Prng)
+  );
+}
+SQLITE_PRIVATE void sqlite3PrngResetState(void){
+  GLOBAL(struct sqlite3PrngType, sqlite3Prng).isInit = 0;
+}
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
 
+/************** End of random.c **********************************************/
+/************** Begin file utf.c *********************************************/
 /*
-** Acquire a lock on the handle h
+** 2004 April 13
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains routines used to translate between UTF-8, 
+** UTF-16, UTF-16BE, and UTF-16LE.
+**
+** Notes on UTF-8:
+**
+**   Byte-0    Byte-1    Byte-2    Byte-3    Value
+**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
+**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
+**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
+**  11110uuu  10uuzzzz  10yyyyyy  10xxxxxx   000uuuuu zzzzyyyy yyxxxxxx
+**
+**
+** Notes on UTF-16:  (with wwww+1==uuuuu)
+**
+**      Word-0               Word-1          Value
+**  110110ww wwzzzzyy   110111yy yyxxxxxx    000uuuuu zzzzyyyy yyxxxxxx
+**  zzzzyyyy yyxxxxxx                        00000000 zzzzyyyy yyxxxxxx
+**
+**
+** BOM or Byte Order Mark:
+**     0xff 0xfe   little-endian utf-16 follows
+**     0xfe 0xff   big-endian utf-16 follows
+**
 */
-static void winceMutexAcquire(HANDLE h){
-   DWORD dwErr;
-   do {
-     dwErr = osWaitForSingleObject(h, INFINITE);
-   } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
-}
+/* #include <assert.h> */
+
+#ifndef SQLITE_AMALGAMATION
 /*
-** Release a lock acquired by winceMutexAcquire()
+** The following constant value is used by the SQLITE_BIGENDIAN and
+** SQLITE_LITTLEENDIAN macros.
 */
-#define winceMutexRelease(h) ReleaseMutex(h)
+SQLITE_PRIVATE const int sqlite3one = 1;
+#endif /* SQLITE_AMALGAMATION */
 
 /*
-** Create the mutex and shared memory used for locking in the file
-** descriptor pFile
+** This lookup table is used to help decode the first byte of
+** a multi-byte UTF8 character.
 */
-static int winceCreateLock(const char *zFilename, winFile *pFile){
-  LPWSTR zTok;
-  LPWSTR zName;
-  DWORD lastErrno;
-  BOOL bLogged = FALSE;
-  BOOL bInit = TRUE;
+static const unsigned char sqlite3Utf8Trans1[] = {
+  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+  0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+  0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+  0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
+};
 
-  zName = winUtf8ToUnicode(zFilename);
-  if( zName==0 ){
-    /* out of memory */
-    return SQLITE_IOERR_NOMEM;
-  }
 
-  /* Initialize the local lockdata */
-  memset(&pFile->local, 0, sizeof(pFile->local));
+#define WRITE_UTF8(zOut, c) {                          \
+  if( c<0x00080 ){                                     \
+    *zOut++ = (u8)(c&0xFF);                            \
+  }                                                    \
+  else if( c<0x00800 ){                                \
+    *zOut++ = 0xC0 + (u8)((c>>6)&0x1F);                \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
+  }                                                    \
+  else if( c<0x10000 ){                                \
+    *zOut++ = 0xE0 + (u8)((c>>12)&0x0F);               \
+    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
+  }else{                                               \
+    *zOut++ = 0xF0 + (u8)((c>>18) & 0x07);             \
+    *zOut++ = 0x80 + (u8)((c>>12) & 0x3F);             \
+    *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);              \
+    *zOut++ = 0x80 + (u8)(c & 0x3F);                   \
+  }                                                    \
+}
 
-  /* Replace the backslashes from the filename and lowercase it
-  ** to derive a mutex name. */
-  zTok = osCharLowerW(zName);
-  for (;*zTok;zTok++){
-    if (*zTok == '\\') *zTok = '_';
-  }
+#define WRITE_UTF16LE(zOut, c) {                                    \
+  if( c<=0xFFFF ){                                                  \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
+  }else{                                                            \
+    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
+    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
+  }                                                                 \
+}
 
-  /* Create/open the named mutex */
-  pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
-  if (!pFile->hMutex){
-    pFile->lastErrno = osGetLastError();
-    sqlite3_free(zName);
-    return winLogError(SQLITE_IOERR, pFile->lastErrno,
-                       "winceCreateLock1", zFilename);
-  }
+#define WRITE_UTF16BE(zOut, c) {                                    \
+  if( c<=0xFFFF ){                                                  \
+    *zOut++ = (u8)((c>>8)&0x00FF);                                  \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+  }else{                                                            \
+    *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03));              \
+    *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0));  \
+    *zOut++ = (u8)(0x00DC + ((c>>8)&0x03));                         \
+    *zOut++ = (u8)(c&0x00FF);                                       \
+  }                                                                 \
+}
 
-  /* Acquire the mutex before continuing */
-  winceMutexAcquire(pFile->hMutex);
-  
-  /* Since the names of named mutexes, semaphores, file mappings etc are 
-  ** case-sensitive, take advantage of that by uppercasing the mutex name
-  ** and using that as the shared filemapping name.
-  */
-  osCharUpperW(zName);
-  pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
-                                        PAGE_READWRITE, 0, sizeof(winceLock),
-                                        zName);  
-
-  /* Set a flag that indicates we're the first to create the memory so it 
-  ** must be zero-initialized */
-  lastErrno = osGetLastError();
-  if (lastErrno == ERROR_ALREADY_EXISTS){
-    bInit = FALSE;
-  }
-
-  sqlite3_free(zName);
-
-  /* If we succeeded in making the shared memory handle, map it. */
-  if( pFile->hShared ){
-    pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared, 
-             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
-    /* If mapping failed, close the shared memory handle and erase it */
-    if( !pFile->shared ){
-      pFile->lastErrno = osGetLastError();
-      winLogError(SQLITE_IOERR, pFile->lastErrno,
-                  "winceCreateLock2", zFilename);
-      bLogged = TRUE;
-      osCloseHandle(pFile->hShared);
-      pFile->hShared = NULL;
-    }
-  }
-
-  /* If shared memory could not be created, then close the mutex and fail */
-  if( pFile->hShared==NULL ){
-    if( !bLogged ){
-      pFile->lastErrno = lastErrno;
-      winLogError(SQLITE_IOERR, pFile->lastErrno,
-                  "winceCreateLock3", zFilename);
-      bLogged = TRUE;
-    }
-    winceMutexRelease(pFile->hMutex);
-    osCloseHandle(pFile->hMutex);
-    pFile->hMutex = NULL;
-    return SQLITE_IOERR;
-  }
-  
-  /* Initialize the shared memory if we're supposed to */
-  if( bInit ){
-    memset(pFile->shared, 0, sizeof(winceLock));
-  }
+#define READ_UTF16LE(zIn, TERM, c){                                   \
+  c = (*zIn++);                                                       \
+  c += ((*zIn++)<<8);                                                 \
+  if( c>=0xD800 && c<0xE000 && TERM ){                                \
+    int c2 = (*zIn++);                                                \
+    c2 += ((*zIn++)<<8);                                              \
+    c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
+  }                                                                   \
+}
 
-  winceMutexRelease(pFile->hMutex);
-  return SQLITE_OK;
+#define READ_UTF16BE(zIn, TERM, c){                                   \
+  c = ((*zIn++)<<8);                                                  \
+  c += (*zIn++);                                                      \
+  if( c>=0xD800 && c<0xE000 && TERM ){                                \
+    int c2 = ((*zIn++)<<8);                                           \
+    c2 += (*zIn++);                                                   \
+    c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10);   \
+  }                                                                   \
 }
 
 /*
-** Destroy the part of winFile that deals with wince locks
+** Translate a single UTF-8 character.  Return the unicode value.
+**
+** During translation, assume that the byte that zTerm points
+** is a 0x00.
+**
+** Write a pointer to the next unread byte back into *pzNext.
+**
+** Notes On Invalid UTF-8:
+**
+**  *  This routine never allows a 7-bit character (0x00 through 0x7f) to
+**     be encoded as a multi-byte character.  Any multi-byte character that
+**     attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
+**
+**  *  This routine never allows a UTF16 surrogate value to be encoded.
+**     If a multi-byte character attempts to encode a value between
+**     0xd800 and 0xe000 then it is rendered as 0xfffd.
+**
+**  *  Bytes in the range of 0x80 through 0xbf which occur as the first
+**     byte of a character are interpreted as single-byte characters
+**     and rendered as themselves even though they are technically
+**     invalid characters.
+**
+**  *  This routine accepts an infinite number of different UTF8 encodings
+**     for unicode values 0x80 and greater.  It do not change over-length
+**     encodings to 0xfffd as some systems recommend.
 */
-static void winceDestroyLock(winFile *pFile){
-  if (pFile->hMutex){
-    /* Acquire the mutex */
-    winceMutexAcquire(pFile->hMutex);
-
-    /* The following blocks should probably assert in debug mode, but they
-       are to cleanup in case any locks remained open */
-    if (pFile->local.nReaders){
-      pFile->shared->nReaders --;
-    }
-    if (pFile->local.bReserved){
-      pFile->shared->bReserved = FALSE;
-    }
-    if (pFile->local.bPending){
-      pFile->shared->bPending = FALSE;
-    }
-    if (pFile->local.bExclusive){
-      pFile->shared->bExclusive = FALSE;
-    }
-
-    /* De-reference and close our copy of the shared memory handle */
-    osUnmapViewOfFile(pFile->shared);
-    osCloseHandle(pFile->hShared);
-
-    /* Done with the mutex */
-    winceMutexRelease(pFile->hMutex);    
-    osCloseHandle(pFile->hMutex);
-    pFile->hMutex = NULL;
+#define READ_UTF8(zIn, zTerm, c)                           \
+  c = *(zIn++);                                            \
+  if( c>=0xc0 ){                                           \
+    c = sqlite3Utf8Trans1[c-0xc0];                         \
+    while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){            \
+      c = (c<<6) + (0x3f & *(zIn++));                      \
+    }                                                      \
+    if( c<0x80                                             \
+        || (c&0xFFFFF800)==0xD800                          \
+        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }        \
   }
-}
-
-/* 
-** An implementation of the LockFile() API of Windows for CE
-*/
-static BOOL winceLockFile(
-  LPHANDLE phFile,
-  DWORD dwFileOffsetLow,
-  DWORD dwFileOffsetHigh,
-  DWORD nNumberOfBytesToLockLow,
-  DWORD nNumberOfBytesToLockHigh
+SQLITE_PRIVATE u32 sqlite3Utf8Read(
+  const unsigned char **pz    /* Pointer to string from which to read char */
 ){
-  winFile *pFile = HANDLE_TO_WINFILE(phFile);
-  BOOL bReturn = FALSE;
-
-  UNUSED_PARAMETER(dwFileOffsetHigh);
-  UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
-
-  if (!pFile->hMutex) return TRUE;
-  winceMutexAcquire(pFile->hMutex);
+  unsigned int c;
 
-  /* Wanting an exclusive lock? */
-  if (dwFileOffsetLow == (DWORD)SHARED_FIRST
-       && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
-    if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
-       pFile->shared->bExclusive = TRUE;
-       pFile->local.bExclusive = TRUE;
-       bReturn = TRUE;
+  /* Same as READ_UTF8() above but without the zTerm parameter.
+  ** For this routine, we assume the UTF8 string is always zero-terminated.
+  */
+  c = *((*pz)++);
+  if( c>=0xc0 ){
+    c = sqlite3Utf8Trans1[c-0xc0];
+    while( (*(*pz) & 0xc0)==0x80 ){
+      c = (c<<6) + (0x3f & *((*pz)++));
     }
+    if( c<0x80
+        || (c&0xFFFFF800)==0xD800
+        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }
   }
+  return c;
+}
 
-  /* Want a read-only lock? */
-  else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
-           nNumberOfBytesToLockLow == 1){
-    if (pFile->shared->bExclusive == 0){
-      pFile->local.nReaders ++;
-      if (pFile->local.nReaders == 1){
-        pFile->shared->nReaders ++;
-      }
-      bReturn = TRUE;
-    }
-  }
 
-  /* Want a pending lock? */
-  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
-           && nNumberOfBytesToLockLow == 1){
-    /* If no pending lock has been acquired, then acquire it */
-    if (pFile->shared->bPending == 0) {
-      pFile->shared->bPending = TRUE;
-      pFile->local.bPending = TRUE;
-      bReturn = TRUE;
-    }
-  }
 
-  /* Want a reserved lock? */
-  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
-           && nNumberOfBytesToLockLow == 1){
-    if (pFile->shared->bReserved == 0) {
-      pFile->shared->bReserved = TRUE;
-      pFile->local.bReserved = TRUE;
-      bReturn = TRUE;
-    }
-  }
 
-  winceMutexRelease(pFile->hMutex);
-  return bReturn;
-}
+/*
+** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
+** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
+*/ 
+/* #define TRANSLATE_TRACE 1 */
 
+#ifndef SQLITE_OMIT_UTF16
 /*
-** An implementation of the UnlockFile API of Windows for CE
+** This routine transforms the internal text encoding used by pMem to
+** desiredEnc. It is an error if the string is already of the desired
+** encoding, or if *pMem does not contain a string value.
 */
-static BOOL winceUnlockFile(
-  LPHANDLE phFile,
-  DWORD dwFileOffsetLow,
-  DWORD dwFileOffsetHigh,
-  DWORD nNumberOfBytesToUnlockLow,
-  DWORD nNumberOfBytesToUnlockHigh
-){
-  winFile *pFile = HANDLE_TO_WINFILE(phFile);
-  BOOL bReturn = FALSE;
-
-  UNUSED_PARAMETER(dwFileOffsetHigh);
-  UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
-
-  if (!pFile->hMutex) return TRUE;
-  winceMutexAcquire(pFile->hMutex);
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
+  int len;                    /* Maximum length of output string in bytes */
+  unsigned char *zOut;                  /* Output buffer */
+  unsigned char *zIn;                   /* Input iterator */
+  unsigned char *zTerm;                 /* End of input */
+  unsigned char *z;                     /* Output iterator */
+  unsigned int c;
 
-  /* Releasing a reader lock or an exclusive lock */
-  if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
-    /* Did we have an exclusive lock? */
-    if (pFile->local.bExclusive){
-      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
-      pFile->local.bExclusive = FALSE;
-      pFile->shared->bExclusive = FALSE;
-      bReturn = TRUE;
-    }
+  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+  assert( pMem->flags&MEM_Str );
+  assert( pMem->enc!=desiredEnc );
+  assert( pMem->enc!=0 );
+  assert( pMem->n>=0 );
 
-    /* Did we just have a reader lock? */
-    else if (pFile->local.nReaders){
-      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
-             || nNumberOfBytesToUnlockLow == 1);
-      pFile->local.nReaders --;
-      if (pFile->local.nReaders == 0)
-      {
-        pFile->shared->nReaders --;
-      }
-      bReturn = TRUE;
-    }
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+  {
+    char zBuf[100];
+    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+    fprintf(stderr, "INPUT:  %s\n", zBuf);
   }
+#endif
 
-  /* Releasing a pending lock */
-  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
-           && nNumberOfBytesToUnlockLow == 1){
-    if (pFile->local.bPending){
-      pFile->local.bPending = FALSE;
-      pFile->shared->bPending = FALSE;
-      bReturn = TRUE;
+  /* If the translation is between UTF-16 little and big endian, then 
+  ** all that is required is to swap the byte order. This case is handled
+  ** differently from the others.
+  */
+  if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){
+    u8 temp;
+    int rc;
+    rc = sqlite3VdbeMemMakeWriteable(pMem);
+    if( rc!=SQLITE_OK ){
+      assert( rc==SQLITE_NOMEM );
+      return SQLITE_NOMEM;
     }
-  }
-  /* Releasing a reserved lock */
-  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
-           && nNumberOfBytesToUnlockLow == 1){
-    if (pFile->local.bReserved) {
-      pFile->local.bReserved = FALSE;
-      pFile->shared->bReserved = FALSE;
-      bReturn = TRUE;
+    zIn = (u8*)pMem->z;
+    zTerm = &zIn[pMem->n&~1];
+    while( zIn<zTerm ){
+      temp = *zIn;
+      *zIn = *(zIn+1);
+      zIn++;
+      *zIn++ = temp;
     }
+    pMem->enc = desiredEnc;
+    goto translate_out;
   }
 
-  winceMutexRelease(pFile->hMutex);
-  return bReturn;
-}
-/*
-** End of the special code for wince
-*****************************************************************************/
-#endif /* SQLITE_OS_WINCE */
-
-/*
-** Lock a file region.
-*/
-static BOOL winLockFile(
-  LPHANDLE phFile,
-  DWORD flags,
-  DWORD offsetLow,
-  DWORD offsetHigh,
-  DWORD numBytesLow,
-  DWORD numBytesHigh
-){
-#if SQLITE_OS_WINCE
-  /*
-  ** NOTE: Windows CE is handled differently here due its lack of the Win32
-  **       API LockFile.
-  */
-  return winceLockFile(phFile, offsetLow, offsetHigh,
-                       numBytesLow, numBytesHigh);
-#else
-  if( osIsNT() ){
-    OVERLAPPED ovlp;
-    memset(&ovlp, 0, sizeof(OVERLAPPED));
-    ovlp.Offset = offsetLow;
-    ovlp.OffsetHigh = offsetHigh;
-    return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
+  /* Set len to the maximum number of bytes required in the output buffer. */
+  if( desiredEnc==SQLITE_UTF8 ){
+    /* When converting from UTF-16, the maximum growth results from
+    ** translating a 2-byte character to a 4-byte UTF-8 character.
+    ** A single byte is required for the output string
+    ** nul-terminator.
+    */
+    pMem->n &= ~1;
+    len = pMem->n * 2 + 1;
   }else{
-    return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
-                      numBytesHigh);
+    /* When converting from UTF-8 to UTF-16 the maximum growth is caused
+    ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
+    ** character. Two bytes are required in the output buffer for the
+    ** nul-terminator.
+    */
+    len = pMem->n * 2 + 2;
   }
-#endif
-}
 
-/*
-** Unlock a file region.
- */
-static BOOL winUnlockFile(
-  LPHANDLE phFile,
-  DWORD offsetLow,
-  DWORD offsetHigh,
-  DWORD numBytesLow,
-  DWORD numBytesHigh
-){
-#if SQLITE_OS_WINCE
-  /*
-  ** NOTE: Windows CE is handled differently here due its lack of the Win32
-  **       API UnlockFile.
+  /* Set zIn to point at the start of the input buffer and zTerm to point 1
+  ** byte past the end.
+  **
+  ** Variable zOut is set to point at the output buffer, space obtained
+  ** from sqlite3_malloc().
   */
-  return winceUnlockFile(phFile, offsetLow, offsetHigh,
-                         numBytesLow, numBytesHigh);
-#else
-  if( osIsNT() ){
-    OVERLAPPED ovlp;
-    memset(&ovlp, 0, sizeof(OVERLAPPED));
-    ovlp.Offset = offsetLow;
-    ovlp.OffsetHigh = offsetHigh;
-    return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
-  }else{
-    return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
-                        numBytesHigh);
+  zIn = (u8*)pMem->z;
+  zTerm = &zIn[pMem->n];
+  zOut = sqlite3DbMallocRaw(pMem->db, len);
+  if( !zOut ){
+    return SQLITE_NOMEM;
   }
-#endif
-}
-
-/*****************************************************************************
-** The next group of routines implement the I/O methods specified
-** by the sqlite3_io_methods object.
-******************************************************************************/
-
-/*
-** Some Microsoft compilers lack this definition.
-*/
-#ifndef INVALID_SET_FILE_POINTER
-# define INVALID_SET_FILE_POINTER ((DWORD)-1)
-#endif
-
-/*
-** Move the current position of the file handle passed as the first 
-** argument to offset iOffset within the file. If successful, return 0. 
-** Otherwise, set pFile->lastErrno and return non-zero.
-*/
-static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
-#if !SQLITE_OS_WINRT
-  LONG upperBits;                 /* Most sig. 32 bits of new offset */
-  LONG lowerBits;                 /* Least sig. 32 bits of new offset */
-  DWORD dwRet;                    /* Value returned by SetFilePointer() */
-  DWORD lastErrno;                /* Value returned by GetLastError() */
-
-  OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
-
-  upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
-  lowerBits = (LONG)(iOffset & 0xffffffff);
-
-  /* API oddity: If successful, SetFilePointer() returns a dword 
-  ** containing the lower 32-bits of the new file-offset. Or, if it fails,
-  ** it returns INVALID_SET_FILE_POINTER. However according to MSDN, 
-  ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine 
-  ** whether an error has actually occurred, it is also necessary to call 
-  ** GetLastError().
-  */
-  dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  z = zOut;
 
-  if( (dwRet==INVALID_SET_FILE_POINTER
-      && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
-    pFile->lastErrno = lastErrno;
-    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
-                "winSeekFile", pFile->zPath);
-    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
-    return 1;
+  if( pMem->enc==SQLITE_UTF8 ){
+    if( desiredEnc==SQLITE_UTF16LE ){
+      /* UTF-8 -> UTF-16 Little-endian */
+      while( zIn<zTerm ){
+        READ_UTF8(zIn, zTerm, c);
+        WRITE_UTF16LE(z, c);
+      }
+    }else{
+      assert( desiredEnc==SQLITE_UTF16BE );
+      /* UTF-8 -> UTF-16 Big-endian */
+      while( zIn<zTerm ){
+        READ_UTF8(zIn, zTerm, c);
+        WRITE_UTF16BE(z, c);
+      }
+    }
+    pMem->n = (int)(z - zOut);
+    *z++ = 0;
+  }else{
+    assert( desiredEnc==SQLITE_UTF8 );
+    if( pMem->enc==SQLITE_UTF16LE ){
+      /* UTF-16 Little-endian -> UTF-8 */
+      while( zIn<zTerm ){
+        READ_UTF16LE(zIn, zIn<zTerm, c); 
+        WRITE_UTF8(z, c);
+      }
+    }else{
+      /* UTF-16 Big-endian -> UTF-8 */
+      while( zIn<zTerm ){
+        READ_UTF16BE(zIn, zIn<zTerm, c); 
+        WRITE_UTF8(z, c);
+      }
+    }
+    pMem->n = (int)(z - zOut);
   }
+  *z = 0;
+  assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
 
-  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
-  return 0;
-#else
-  /*
-  ** Same as above, except that this implementation works for WinRT.
-  */
-
-  LARGE_INTEGER x;                /* The new offset */
-  BOOL bRet;                      /* Value returned by SetFilePointerEx() */
-
-  x.QuadPart = iOffset;
-  bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
+  sqlite3VdbeMemRelease(pMem);
+  pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem);
+  pMem->enc = desiredEnc;
+  pMem->flags |= (MEM_Term|MEM_Dyn);
+  pMem->z = (char*)zOut;
+  pMem->zMalloc = pMem->z;
 
-  if(!bRet){
-    pFile->lastErrno = osGetLastError();
-    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
-                "winSeekFile", pFile->zPath);
-    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
-    return 1;
+translate_out:
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+  {
+    char zBuf[100];
+    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+    fprintf(stderr, "OUTPUT: %s\n", zBuf);
   }
-
-  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
-  return 0;
 #endif
+  return SQLITE_OK;
 }
 
-#if SQLITE_MAX_MMAP_SIZE>0
-/* Forward references to VFS helper methods used for memory mapped files */
-static int winMapfile(winFile*, sqlite3_int64);
-static int winUnmapfile(winFile*);
-#endif
-
 /*
-** Close a file.
+** This routine checks for a byte-order mark at the beginning of the 
+** UTF-16 string stored in *pMem. If one is present, it is removed and
+** the encoding of the Mem adjusted. This routine does not do any
+** byte-swapping, it just sets Mem.enc appropriately.
 **
-** It is reported that an attempt to close a handle might sometimes
-** fail.  This is a very unreasonable result, but Windows is notorious
-** for being unreasonable so I do not doubt that it might happen.  If
-** the close fails, we pause for 100 milliseconds and try again.  As
-** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
-** giving up and returning an error.
+** The allocation (static, dynamic etc.) and encoding of the Mem may be
+** changed by this function.
 */
-#define MX_CLOSE_ATTEMPT 3
-static int winClose(sqlite3_file *id){
-  int rc, cnt = 0;
-  winFile *pFile = (winFile*)id;
-
-  assert( id!=0 );
-#ifndef SQLITE_OMIT_WAL
-  assert( pFile->pShm==0 );
-#endif
-  assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
-  OSTRACE(("CLOSE file=%p\n", pFile->h));
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  winUnmapfile(pFile);
-#endif
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem){
+  int rc = SQLITE_OK;
+  u8 bom = 0;
 
-  do{
-    rc = osCloseHandle(pFile->h);
-    /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
-  }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
-#if SQLITE_OS_WINCE
-#define WINCE_DELETION_ATTEMPTS 3
-  winceDestroyLock(pFile);
-  if( pFile->zDeleteOnClose ){
-    int cnt = 0;
-    while(
-           osDeleteFileW(pFile->zDeleteOnClose)==0
-        && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff 
-        && cnt++ < WINCE_DELETION_ATTEMPTS
-    ){
-       sqlite3_win32_sleep(100);  /* Wait a little before trying again */
+  assert( pMem->n>=0 );
+  if( pMem->n>1 ){
+    u8 b1 = *(u8 *)pMem->z;
+    u8 b2 = *(((u8 *)pMem->z) + 1);
+    if( b1==0xFE && b2==0xFF ){
+      bom = SQLITE_UTF16BE;
+    }
+    if( b1==0xFF && b2==0xFE ){
+      bom = SQLITE_UTF16LE;
     }
-    sqlite3_free(pFile->zDeleteOnClose);
   }
-#endif
-  if( rc ){
-    pFile->h = NULL;
+  
+  if( bom ){
+    rc = sqlite3VdbeMemMakeWriteable(pMem);
+    if( rc==SQLITE_OK ){
+      pMem->n -= 2;
+      memmove(pMem->z, &pMem->z[2], pMem->n);
+      pMem->z[pMem->n] = '\0';
+      pMem->z[pMem->n+1] = '\0';
+      pMem->flags |= MEM_Term;
+      pMem->enc = bom;
+    }
   }
-  OpenCounter(-1);
-  OSTRACE(("CLOSE file=%p, rc=%s\n", pFile->h, rc ? "ok" : "failed"));
-  return rc ? SQLITE_OK
-            : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
-                          "winClose", pFile->zPath);
+  return rc;
 }
+#endif /* SQLITE_OMIT_UTF16 */
 
 /*
-** Read data from a file into a buffer.  Return SQLITE_OK if all
-** bytes were read successfully and SQLITE_IOERR if anything goes
-** wrong.
+** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
+** return the number of unicode characters in pZ up to (but not including)
+** the first 0x00 byte. If nByte is not less than zero, return the
+** number of unicode characters in the first nByte of pZ (or up to 
+** the first 0x00, whichever comes first).
 */
-static int winRead(
-  sqlite3_file *id,          /* File to read from */
-  void *pBuf,                /* Write content into this buffer */
-  int amt,                   /* Number of bytes to read */
-  sqlite3_int64 offset       /* Begin reading at this offset */
-){
-#if !SQLITE_OS_WINCE
-  OVERLAPPED overlapped;          /* The offset for ReadFile. */
-#endif
-  winFile *pFile = (winFile*)id;  /* file handle */
-  DWORD nRead;                    /* Number of bytes actually read from file */
-  int nRetry = 0;                 /* Number of retrys */
-
-  assert( id!=0 );
-  assert( amt>0 );
-  assert( offset>=0 );
-  SimulateIOError(return SQLITE_IOERR_READ);
-  OSTRACE(("READ file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
-           pFile->h, pBuf, amt, offset, pFile->locktype));
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* Deal with as much of this read request as possible by transfering
-  ** data from the memory mapping using memcpy().  */
-  if( offset<pFile->mmapSize ){
-    if( offset+amt <= pFile->mmapSize ){
-      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
-      OSTRACE(("READ-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }else{
-      int nCopy = (int)(pFile->mmapSize - offset);
-      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
-      pBuf = &((u8 *)pBuf)[nCopy];
-      amt -= nCopy;
-      offset += nCopy;
-    }
-  }
-#endif
-
-#if SQLITE_OS_WINCE
-  if( winSeekFile(pFile, offset) ){
-    OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
-    return SQLITE_FULL;
+SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *zIn, int nByte){
+  int r = 0;
+  const u8 *z = (const u8*)zIn;
+  const u8 *zTerm;
+  if( nByte>=0 ){
+    zTerm = &z[nByte];
+  }else{
+    zTerm = (const u8*)(-1);
   }
-  while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
-#else
-  memset(&overlapped, 0, sizeof(OVERLAPPED));
-  overlapped.Offset = (LONG)(offset & 0xffffffff);
-  overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
-  while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
-         osGetLastError()!=ERROR_HANDLE_EOF ){
-#endif
-    DWORD lastErrno;
-    if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
-    pFile->lastErrno = lastErrno;
-    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
-    return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
-                       "winRead", pFile->zPath);
-  }
-  winLogIoerr(nRetry);
-  if( nRead<(DWORD)amt ){
-    /* Unread parts of the buffer must be zero-filled */
-    memset(&((char*)pBuf)[nRead], 0, amt-nRead);
-    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
-    return SQLITE_IOERR_SHORT_READ;
+  assert( z<=zTerm );
+  while( *z!=0 && z<zTerm ){
+    SQLITE_SKIP_UTF8(z);
+    r++;
   }
-
-  OSTRACE(("READ file=%p, rc=SQLITE_OK\n", pFile->h));
-  return SQLITE_OK;
+  return r;
 }
 
+/* This test function is not currently used by the automated test-suite. 
+** Hence it is only available in debug builds.
+*/
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
 /*
-** Write data from a buffer into a file.  Return SQLITE_OK on success
-** or some other error code on failure.
+** Translate UTF-8 to UTF-8.
+**
+** This has the effect of making sure that the string is well-formed
+** UTF-8.  Miscoded characters are removed.
+**
+** The translation is done in-place and aborted if the output
+** overruns the input.
 */
-static int winWrite(
-  sqlite3_file *id,               /* File to write into */
-  const void *pBuf,               /* The bytes to be written */
-  int amt,                        /* Number of bytes to write */
-  sqlite3_int64 offset            /* Offset into the file to begin writing at */
-){
-  int rc = 0;                     /* True if error has occurred, else false */
-  winFile *pFile = (winFile*)id;  /* File handle */
-  int nRetry = 0;                 /* Number of retries */
-
-  assert( amt>0 );
-  assert( pFile );
-  SimulateIOError(return SQLITE_IOERR_WRITE);
-  SimulateDiskfullError(return SQLITE_FULL);
-
-  OSTRACE(("WRITE file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
-           pFile->h, pBuf, amt, offset, pFile->locktype));
+SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char *zIn){
+  unsigned char *zOut = zIn;
+  unsigned char *zStart = zIn;
+  u32 c;
 
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* Deal with as much of this write request as possible by transfering
-  ** data from the memory mapping using memcpy().  */
-  if( offset<pFile->mmapSize ){
-    if( offset+amt <= pFile->mmapSize ){
-      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
-      OSTRACE(("WRITE-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }else{
-      int nCopy = (int)(pFile->mmapSize - offset);
-      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
-      pBuf = &((u8 *)pBuf)[nCopy];
-      amt -= nCopy;
-      offset += nCopy;
+  while( zIn[0] && zOut<=zIn ){
+    c = sqlite3Utf8Read((const u8**)&zIn);
+    if( c!=0xfffd ){
+      WRITE_UTF8(zOut, c);
     }
   }
+  *zOut = 0;
+  return (int)(zOut - zStart);
+}
 #endif
 
-#if SQLITE_OS_WINCE
-  rc = winSeekFile(pFile, offset);
-  if( rc==0 ){
-#else
-  {
-#endif
-#if !SQLITE_OS_WINCE
-    OVERLAPPED overlapped;        /* The offset for WriteFile. */
-#endif
-    u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
-    int nRem = amt;               /* Number of bytes yet to be written */
-    DWORD nWrite;                 /* Bytes written by each WriteFile() call */
-    DWORD lastErrno = NO_ERROR;   /* Value returned by GetLastError() */
-
-#if !SQLITE_OS_WINCE
-    memset(&overlapped, 0, sizeof(OVERLAPPED));
-    overlapped.Offset = (LONG)(offset & 0xffffffff);
-    overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
-#endif
-
-    while( nRem>0 ){
-#if SQLITE_OS_WINCE
-      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
-#else
-      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
-#endif
-        if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
-        break;
-      }
-      assert( nWrite==0 || nWrite<=(DWORD)nRem );
-      if( nWrite==0 || nWrite>(DWORD)nRem ){
-        lastErrno = osGetLastError();
-        break;
-      }
-#if !SQLITE_OS_WINCE
-      offset += nWrite;
-      overlapped.Offset = (LONG)(offset & 0xffffffff);
-      overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
-#endif
-      aRem += nWrite;
-      nRem -= nWrite;
-    }
-    if( nRem>0 ){
-      pFile->lastErrno = lastErrno;
-      rc = 1;
-    }
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Convert a UTF-16 string in the native encoding into a UTF-8 string.
+** Memory to hold the UTF-8 string is obtained from sqlite3_malloc and must
+** be freed by the calling function.
+**
+** NULL is returned if there is an allocation error.
+*/
+SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte, u8 enc){
+  Mem m;
+  memset(&m, 0, sizeof(m));
+  m.db = db;
+  sqlite3VdbeMemSetStr(&m, z, nByte, enc, SQLITE_STATIC);
+  sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8);
+  if( db->mallocFailed ){
+    sqlite3VdbeMemRelease(&m);
+    m.z = 0;
   }
+  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
+  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
+  assert( (m.flags & MEM_Dyn)!=0 || db->mallocFailed );
+  assert( m.z || db->mallocFailed );
+  return m.z;
+}
 
-  if( rc ){
-    if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
-       || ( pFile->lastErrno==ERROR_DISK_FULL )){
-      OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
-      return winLogError(SQLITE_FULL, pFile->lastErrno,
-                         "winWrite1", pFile->zPath);
-    }
-    OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
-    return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
-                       "winWrite2", pFile->zPath);
+/*
+** zIn is a UTF-16 encoded unicode string at least nChar characters long.
+** Return the number of bytes in the first nChar unicode characters
+** in pZ.  nChar must be non-negative.
+*/
+SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
+  int c;
+  unsigned char const *z = zIn;
+  int n = 0;
+  
+  if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
+    while( n<nChar ){
+      READ_UTF16BE(z, 1, c);
+      n++;
+    }
   }else{
-    winLogIoerr(nRetry);
+    while( n<nChar ){
+      READ_UTF16LE(z, 1, c);
+      n++;
+    }
   }
-  OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
-  return SQLITE_OK;
+  return (int)(z-(unsigned char const *)zIn);
 }
 
+#if defined(SQLITE_TEST)
 /*
-** Truncate an open file to a specified size
+** This routine is called from the TCL test function "translate_selftest".
+** It checks that the primitives for serializing and deserializing
+** characters in each encoding are inverses of each other.
 */
-static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
-  winFile *pFile = (winFile*)id;  /* File handle object */
-  int rc = SQLITE_OK;             /* Return code for this function */
-  DWORD lastErrno;
-
-  assert( pFile );
-  SimulateIOError(return SQLITE_IOERR_TRUNCATE);
-  OSTRACE(("TRUNCATE file=%p, size=%lld, lock=%d\n",
-           pFile->h, nByte, pFile->locktype));
+SQLITE_PRIVATE void sqlite3UtfSelfTest(void){
+  unsigned int i, t;
+  unsigned char zBuf[20];
+  unsigned char *z;
+  int n;
+  unsigned int c;
 
-  /* If the user has configured a chunk-size for this file, truncate the
-  ** file so that it consists of an integer number of chunks (i.e. the
-  ** actual file size after the operation may be larger than the requested
-  ** size).
-  */
-  if( pFile->szChunk>0 ){
-    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+  for(i=0; i<0x00110000; i++){
+    z = zBuf;
+    WRITE_UTF8(z, i);
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
+    z[0] = 0;
+    z = zBuf;
+    c = sqlite3Utf8Read((const u8**)&z);
+    t = i;
+    if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
+    if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
+    assert( c==t );
+    assert( (z-zBuf)==n );
   }
-
-  /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
-  if( winSeekFile(pFile, nByte) ){
-    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
-                     "winTruncate1", pFile->zPath);
-  }else if( 0==osSetEndOfFile(pFile->h) &&
-            ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
-    pFile->lastErrno = lastErrno;
-    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
-                     "winTruncate2", pFile->zPath);
+  for(i=0; i<0x00110000; i++){
+    if( i>=0xD800 && i<0xE000 ) continue;
+    z = zBuf;
+    WRITE_UTF16LE(z, i);
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
+    z[0] = 0;
+    z = zBuf;
+    READ_UTF16LE(z, 1, c);
+    assert( c==i );
+    assert( (z-zBuf)==n );
   }
-
-#if SQLITE_MAX_MMAP_SIZE>0
-  /* If the file was truncated to a size smaller than the currently
-  ** mapped region, reduce the effective mapping size as well. SQLite will
-  ** use read() and write() to access data beyond this point from now on.
-  */
-  if( pFile->pMapRegion && nByte<pFile->mmapSize ){
-    pFile->mmapSize = nByte;
+  for(i=0; i<0x00110000; i++){
+    if( i>=0xD800 && i<0xE000 ) continue;
+    z = zBuf;
+    WRITE_UTF16BE(z, i);
+    n = (int)(z-zBuf);
+    assert( n>0 && n<=4 );
+    z[0] = 0;
+    z = zBuf;
+    READ_UTF16BE(z, 1, c);
+    assert( c==i );
+    assert( (z-zBuf)==n );
   }
-#endif
-
-  OSTRACE(("TRUNCATE file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
-  return rc;
 }
+#endif /* SQLITE_TEST */
+#endif /* SQLITE_OMIT_UTF16 */
 
-#ifdef SQLITE_TEST
+/************** End of utf.c *************************************************/
+/************** Begin file util.c ********************************************/
 /*
-** Count the number of fullsyncs and normal syncs.  This is used to test
-** that syncs and fullsyncs are occuring at the right times.
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Utility functions used throughout sqlite.
+**
+** This file contains functions for allocating memory, comparing
+** strings, and stuff like that.
+**
 */
-SQLITE_API int sqlite3_sync_count = 0;
-SQLITE_API int sqlite3_fullsync_count = 0;
+/* #include <stdarg.h> */
+#ifdef SQLITE_HAVE_ISNAN
+# include <math.h>
 #endif
 
 /*
-** Make sure all writes to a particular file are committed to disk.
+** Routine needed to support the testcase() macro.
 */
-static int winSync(sqlite3_file *id, int flags){
-#ifndef SQLITE_NO_SYNC
-  /*
-  ** Used only when SQLITE_NO_SYNC is not defined.
-   */
-  BOOL rc;
-#endif
-#if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
-    (defined(SQLITE_TEST) && defined(SQLITE_DEBUG))
-  /*
-  ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
-  ** OSTRACE() macros.
-   */
-  winFile *pFile = (winFile*)id;
-#else
-  UNUSED_PARAMETER(id);
-#endif
-
-  assert( pFile );
-  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
-  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
-      || (flags&0x0F)==SQLITE_SYNC_FULL
-  );
-
-  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
-  ** line is to test that doing so does not cause any problems.
-  */
-  SimulateDiskfullError( return SQLITE_FULL );
-
-  OSTRACE(("SYNC file=%p, flags=%x, lock=%d\n",
-           pFile->h, flags, pFile->locktype));
-
-#ifndef SQLITE_TEST
-  UNUSED_PARAMETER(flags);
-#else
-  if( (flags&0x0F)==SQLITE_SYNC_FULL ){
-    sqlite3_fullsync_count++;
-  }
-  sqlite3_sync_count++;
-#endif
-
-  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
-  ** no-op
-  */
-#ifdef SQLITE_NO_SYNC
-  OSTRACE(("SYNC-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
-  return SQLITE_OK;
-#else
-  rc = osFlushFileBuffers(pFile->h);
-  SimulateIOError( rc=FALSE );
-  if( rc ){
-    OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
-    return SQLITE_OK;
-  }else{
-    pFile->lastErrno = osGetLastError();
-    OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
-    return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
-                       "winSync", pFile->zPath);
-  }
-#endif
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int x){
+  static unsigned dummy = 0;
+  dummy += (unsigned)x;
 }
+#endif
 
+#ifndef SQLITE_OMIT_FLOATING_POINT
 /*
-** Determine the current size of a file in bytes
+** Return true if the floating point value is Not a Number (NaN).
+**
+** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
+** Otherwise, we have our own implementation that works on most systems.
 */
-static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
-  winFile *pFile = (winFile*)id;
-  int rc = SQLITE_OK;
-
-  assert( id!=0 );
-  assert( pSize!=0 );
-  SimulateIOError(return SQLITE_IOERR_FSTAT);
-  OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
-
-#if SQLITE_OS_WINRT
-  {
-    FILE_STANDARD_INFO info;
-    if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
-                                     &info, sizeof(info)) ){
-      *pSize = info.EndOfFile.QuadPart;
-    }else{
-      pFile->lastErrno = osGetLastError();
-      rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
-                       "winFileSize", pFile->zPath);
-    }
-  }
-#else
-  {
-    DWORD upperBits;
-    DWORD lowerBits;
-    DWORD lastErrno;
-
-    lowerBits = osGetFileSize(pFile->h, &upperBits);
-    *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
-    if(   (lowerBits == INVALID_FILE_SIZE)
-       && ((lastErrno = osGetLastError())!=NO_ERROR) ){
-      pFile->lastErrno = lastErrno;
-      rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
-                       "winFileSize", pFile->zPath);
-    }
-  }
+SQLITE_PRIVATE int sqlite3IsNaN(double x){
+  int rc;   /* The value return */
+#if !defined(SQLITE_HAVE_ISNAN)
+  /*
+  ** Systems that support the isnan() library function should probably
+  ** make use of it by compiling with -DSQLITE_HAVE_ISNAN.  But we have
+  ** found that many systems do not have a working isnan() function so
+  ** this implementation is provided as an alternative.
+  **
+  ** This NaN test sometimes fails if compiled on GCC with -ffast-math.
+  ** On the other hand, the use of -ffast-math comes with the following
+  ** warning:
+  **
+  **      This option [-ffast-math] should never be turned on by any
+  **      -O option since it can result in incorrect output for programs
+  **      which depend on an exact implementation of IEEE or ISO 
+  **      rules/specifications for math functions.
+  **
+  ** Under MSVC, this NaN test may fail if compiled with a floating-
+  ** point precision mode other than /fp:precise.  From the MSDN 
+  ** documentation:
+  **
+  **      The compiler [with /fp:precise] will properly handle comparisons 
+  **      involving NaN. For example, x != x evaluates to true if x is NaN 
+  **      ...
+  */
+#ifdef __FAST_MATH__
+# error SQLite will not work correctly with the -ffast-math option of GCC.
 #endif
-  OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
-           pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
+  volatile double y = x;
+  volatile double z = y;
+  rc = (y!=z);
+#else  /* if defined(SQLITE_HAVE_ISNAN) */
+  rc = isnan(x);
+#endif /* SQLITE_HAVE_ISNAN */
+  testcase( rc );
   return rc;
 }
+#endif /* SQLITE_OMIT_FLOATING_POINT */
 
 /*
-** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
+** Compute a string length that is limited to what can be stored in
+** lower 30 bits of a 32-bit signed integer.
+**
+** The value returned will never be negative.  Nor will it ever be greater
+** than the actual length of the string.  For very long strings (greater
+** than 1GiB) the value returned might be less than the true string length.
 */
-#ifndef LOCKFILE_FAIL_IMMEDIATELY
-# define LOCKFILE_FAIL_IMMEDIATELY 1
-#endif
-
-#ifndef LOCKFILE_EXCLUSIVE_LOCK
-# define LOCKFILE_EXCLUSIVE_LOCK 2
-#endif
+SQLITE_PRIVATE int sqlite3Strlen30(const char *z){
+  const char *z2 = z;
+  if( z==0 ) return 0;
+  while( *z2 ){ z2++; }
+  return 0x3fffffff & (int)(z2 - z);
+}
 
 /*
-** Historically, SQLite has used both the LockFile and LockFileEx functions.
-** When the LockFile function was used, it was always expected to fail
-** immediately if the lock could not be obtained.  Also, it always expected to
-** obtain an exclusive lock.  These flags are used with the LockFileEx function
-** and reflect those expectations; therefore, they should not be changed.
+** Set the most recent error code and error string for the sqlite
+** handle "db". The error code is set to "err_code".
+**
+** If it is not NULL, string zFormat specifies the format of the
+** error string in the style of the printf functions: The following
+** format characters are allowed:
+**
+**      %s      Insert a string
+**      %z      A string that should be freed after use
+**      %d      Insert an integer
+**      %T      Insert a token
+**      %S      Insert the first element of a SrcList
+**
+** zFormat and any string tokens that follow it are assumed to be
+** encoded in UTF-8.
+**
+** To clear the most recent error for sqlite handle "db", sqlite3Error
+** should be called with err_code set to SQLITE_OK and zFormat set
+** to NULL.
 */
-#ifndef SQLITE_LOCKFILE_FLAGS
-# define SQLITE_LOCKFILE_FLAGS   (LOCKFILE_FAIL_IMMEDIATELY | \
-                                  LOCKFILE_EXCLUSIVE_LOCK)
-#endif
+SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat, ...){
+  if( db && (db->pErr || (db->pErr = sqlite3ValueNew(db))!=0) ){
+    db->errCode = err_code;
+    if( zFormat ){
+      char *z;
+      va_list ap;
+      va_start(ap, zFormat);
+      z = sqlite3VMPrintf(db, zFormat, ap);
+      va_end(ap);
+      sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
+    }else{
+      sqlite3ValueSetStr(db->pErr, 0, 0, SQLITE_UTF8, SQLITE_STATIC);
+    }
+  }
+}
 
 /*
-** Currently, SQLite never calls the LockFileEx function without wanting the
-** call to fail immediately if the lock cannot be obtained.
+** Add an error message to pParse->zErrMsg and increment pParse->nErr.
+** The following formatting characters are allowed:
+**
+**      %s      Insert a string
+**      %z      A string that should be freed after use
+**      %d      Insert an integer
+**      %T      Insert a token
+**      %S      Insert the first element of a SrcList
+**
+** This function should be used to report any error that occurs whilst
+** compiling an SQL statement (i.e. within sqlite3_prepare()). The
+** last thing the sqlite3_prepare() function does is copy the error
+** stored by this function into the database handle using sqlite3Error().
+** Function sqlite3Error() should be used during statement execution
+** (sqlite3_step() etc.).
 */
-#ifndef SQLITE_LOCKFILEEX_FLAGS
-# define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
-#endif
+SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
+  char *zMsg;
+  va_list ap;
+  sqlite3 *db = pParse->db;
+  va_start(ap, zFormat);
+  zMsg = sqlite3VMPrintf(db, zFormat, ap);
+  va_end(ap);
+  if( db->suppressErr ){
+    sqlite3DbFree(db, zMsg);
+  }else{
+    pParse->nErr++;
+    sqlite3DbFree(db, pParse->zErrMsg);
+    pParse->zErrMsg = zMsg;
+    pParse->rc = SQLITE_ERROR;
+  }
+}
 
 /*
-** Acquire a reader lock.
-** Different API routines are called depending on whether or not this
-** is Win9x or WinNT.
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters.  The conversion is done in-place.  If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** The input string must be zero-terminated.  A new zero-terminator
+** is added to the dequoted string.
+**
+** The return value is -1 if no dequoting occurs or the length of the
+** dequoted string, exclusive of the zero terminator, if dequoting does
+** occur.
+**
+** 2002-Feb-14: This routine is extended to remove MS-Access style
+** brackets from around identifers.  For example:  "[a-b-c]" becomes
+** "a-b-c".
 */
-static int winGetReadLock(winFile *pFile){
-  int res;
-  OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
-  if( osIsNT() ){
-#if SQLITE_OS_WINCE
-    /*
-    ** NOTE: Windows CE is handled differently here due its lack of the Win32
-    **       API LockFileEx.
-    */
-    res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
-#else
-    res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
-                      SHARED_SIZE, 0);
-#endif
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    int lk;
-    sqlite3_randomness(sizeof(lk), &lk);
-    pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
-    res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
-                      SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+SQLITE_PRIVATE int sqlite3Dequote(char *z){
+  char quote;
+  int i, j;
+  if( z==0 ) return -1;
+  quote = z[0];
+  switch( quote ){
+    case '\'':  break;
+    case '"':   break;
+    case '`':   break;                /* For MySQL compatibility */
+    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
+    default:    return -1;
   }
-#endif
-  if( res == 0 ){
-    pFile->lastErrno = osGetLastError();
-    /* No need to log a failure to lock */
+  for(i=1, j=0;; i++){
+    assert( z[i] );
+    if( z[i]==quote ){
+      if( z[i+1]==quote ){
+        z[j++] = quote;
+        i++;
+      }else{
+        break;
+      }
+    }else{
+      z[j++] = z[i];
+    }
   }
-  OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
-  return res;
+  z[j] = 0;
+  return j;
 }
 
+/* Convenient short-hand */
+#define UpperToLower sqlite3UpperToLower
+
 /*
-** Undo a readlock
+** Some systems have stricmp().  Others have strcasecmp().  Because
+** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
+** sqlite3_strnicmp() APIs allow applications and extensions to compare
+** the contents of two buffers containing UTF-8 strings in a
+** case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
 */
-static int winUnlockReadLock(winFile *pFile){
-  int res;
-  DWORD lastErrno;
-  OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
-  if( osIsNT() ){
-    res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
-  }
-#endif
-  if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
-    pFile->lastErrno = lastErrno;
-    winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
-                "winUnlockReadLock", pFile->zPath);
-  }
-  OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
-  return res;
+SQLITE_API int sqlite3_stricmp(const char *zLeft, const char *zRight){
+  register unsigned char *a, *b;
+  a = (unsigned char *)zLeft;
+  b = (unsigned char *)zRight;
+  while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+  return UpperToLower[*a] - UpperToLower[*b];
+}
+SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
+  register unsigned char *a, *b;
+  a = (unsigned char *)zLeft;
+  b = (unsigned char *)zRight;
+  while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+  return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
 }
 
 /*
-** Lock the file with the lock specified by parameter locktype - one
-** of the following:
+** The string z[] is an text representation of a real number.
+** Convert this string to a double and write it into *pResult.
 **
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
+** The string z[] is length bytes in length (bytes, not characters) and
+** uses the encoding enc.  The string is not necessarily zero-terminated.
 **
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
+** Return TRUE if the result is a valid real number (or integer) and FALSE
+** if the string is empty or contains extraneous text.  Valid numbers
+** are in one of these formats:
 **
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
+**    [+-]digits[E[+-]digits]
+**    [+-]digits.[digits][E[+-]digits]
+**    [+-].digits[E[+-]digits]
 **
-** This routine will only increase a lock.  The winUnlock() routine
-** erases all locks at once and returns us immediately to locking level 0.
-** It is not possible to lower the locking level one step at a time.  You
-** must go straight to locking level 0.
-*/
-static int winLock(sqlite3_file *id, int locktype){
-  int rc = SQLITE_OK;    /* Return code from subroutines */
-  int res = 1;           /* Result of a Windows lock call */
-  int newLocktype;       /* Set pFile->locktype to this value before exiting */
-  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
-  winFile *pFile = (winFile*)id;
-  DWORD lastErrno = NO_ERROR;
-
-  assert( id!=0 );
-  OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
-           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
-
-  /* If there is already a lock of this type or more restrictive on the
-  ** OsFile, do nothing. Don't use the end_lock: exit path, as
-  ** sqlite3OsEnterMutex() hasn't been called yet.
-  */
-  if( pFile->locktype>=locktype ){
-    OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
-    return SQLITE_OK;
-  }
+** Leading and trailing whitespace is ignored for the purpose of determining
+** validity.
+**
+** If some prefix of the input string is a valid number, this routine
+** returns FALSE but it still converts the prefix and writes the result
+** into *pResult.
+*/
+SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
+#ifndef SQLITE_OMIT_FLOATING_POINT
+  int incr;
+  const char *zEnd = z + length;
+  /* sign * significand * (10 ^ (esign * exponent)) */
+  int sign = 1;    /* sign of significand */
+  i64 s = 0;       /* significand */
+  int d = 0;       /* adjust exponent for shifting decimal point */
+  int esign = 1;   /* sign of exponent */
+  int e = 0;       /* exponent */
+  int eValid = 1;  /* True exponent is either not used or is well-formed */
+  double result;
+  int nDigits = 0;
+  int nonNum = 0;
 
-  /* Make sure the locking sequence is correct
-  */
-  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
-  assert( locktype!=PENDING_LOCK );
-  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
+  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+  *pResult = 0.0;   /* Default return value, in case of an error */
 
-  /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
-  ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
-  ** the PENDING_LOCK byte is temporary.
-  */
-  newLocktype = pFile->locktype;
-  if(   (pFile->locktype==NO_LOCK)
-     || (   (locktype==EXCLUSIVE_LOCK)
-         && (pFile->locktype==RESERVED_LOCK))
-  ){
-    int cnt = 3;
-    while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
-                                         PENDING_BYTE, 0, 1, 0))==0 ){
-      /* Try 3 times to get the pending lock.  This is needed to work
-      ** around problems caused by indexing and/or anti-virus software on
-      ** Windows systems.
-      ** If you are using this code as a model for alternative VFSes, do not
-      ** copy this retry logic.  It is a hack intended for Windows only.
-      */
-      OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, rc=%s\n",
-               pFile->h, cnt, sqlite3ErrName(res)));
-      if( cnt ) sqlite3_win32_sleep(1);
-    }
-    gotPendingLock = res;
-    if( !res ){
-      lastErrno = osGetLastError();
-    }
+  if( enc==SQLITE_UTF8 ){
+    incr = 1;
+  }else{
+    int i;
+    incr = 2;
+    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+    for(i=3-enc; i<length && z[i]==0; i+=2){}
+    nonNum = i<length;
+    zEnd = z+i+enc-3;
+    z += (enc&1);
   }
 
-  /* Acquire a shared lock
-  */
-  if( locktype==SHARED_LOCK && res ){
-    assert( pFile->locktype==NO_LOCK );
-    res = winGetReadLock(pFile);
-    if( res ){
-      newLocktype = SHARED_LOCK;
-    }else{
-      lastErrno = osGetLastError();
-    }
-  }
+  /* skip leading spaces */
+  while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
+  if( z>=zEnd ) return 0;
 
-  /* Acquire a RESERVED lock
-  */
-  if( locktype==RESERVED_LOCK && res ){
-    assert( pFile->locktype==SHARED_LOCK );
-    res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
-    if( res ){
-      newLocktype = RESERVED_LOCK;
-    }else{
-      lastErrno = osGetLastError();
-    }
+  /* get sign of significand */
+  if( *z=='-' ){
+    sign = -1;
+    z+=incr;
+  }else if( *z=='+' ){
+    z+=incr;
   }
 
-  /* Acquire a PENDING lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res ){
-    newLocktype = PENDING_LOCK;
-    gotPendingLock = 0;
-  }
+  /* skip leading zeroes */
+  while( z<zEnd && z[0]=='0' ) z+=incr, nDigits++;
 
-  /* Acquire an EXCLUSIVE lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res ){
-    assert( pFile->locktype>=SHARED_LOCK );
-    res = winUnlockReadLock(pFile);
-    res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
-                      SHARED_SIZE, 0);
-    if( res ){
-      newLocktype = EXCLUSIVE_LOCK;
-    }else{
-      lastErrno = osGetLastError();
-      winGetReadLock(pFile);
-    }
+  /* copy max significant digits to significand */
+  while( z<zEnd && sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
+    s = s*10 + (*z - '0');
+    z+=incr, nDigits++;
   }
 
-  /* If we are holding a PENDING lock that ought to be released, then
-  ** release it now.
-  */
-  if( gotPendingLock && locktype==SHARED_LOCK ){
-    winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
-  }
+  /* skip non-significant significand digits
+  ** (increase exponent by d to shift decimal left) */
+  while( z<zEnd && sqlite3Isdigit(*z) ) z+=incr, nDigits++, d++;
+  if( z>=zEnd ) goto do_atof_calc;
 
-  /* Update the state of the lock has held in the file descriptor then
-  ** return the appropriate result code.
-  */
-  if( res ){
-    rc = SQLITE_OK;
-  }else{
-    pFile->lastErrno = lastErrno;
-    rc = SQLITE_BUSY;
-    OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
-             pFile->h, locktype, newLocktype));
+  /* if decimal point is present */
+  if( *z=='.' ){
+    z+=incr;
+    /* copy digits from after decimal to significand
+    ** (decrease exponent by d to shift decimal right) */
+    while( z<zEnd && sqlite3Isdigit(*z) && s<((LARGEST_INT64-9)/10) ){
+      s = s*10 + (*z - '0');
+      z+=incr, nDigits++, d--;
+    }
+    /* skip non-significant digits */
+    while( z<zEnd && sqlite3Isdigit(*z) ) z+=incr, nDigits++;
   }
-  pFile->locktype = (u8)newLocktype;
-  OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
-           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
-  return rc;
-}
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, return
-** non-zero, otherwise zero.
-*/
-static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
-  int rc;
-  winFile *pFile = (winFile*)id;
-
-  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
+  if( z>=zEnd ) goto do_atof_calc;
 
-  assert( id!=0 );
-  if( pFile->locktype>=RESERVED_LOCK ){
-    rc = 1;
-    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
-  }else{
-    rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
-    if( rc ){
-      winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
+  /* if exponent is present */
+  if( *z=='e' || *z=='E' ){
+    z+=incr;
+    eValid = 0;
+    if( z>=zEnd ) goto do_atof_calc;
+    /* get sign of exponent */
+    if( *z=='-' ){
+      esign = -1;
+      z+=incr;
+    }else if( *z=='+' ){
+      z+=incr;
+    }
+    /* copy digits to exponent */
+    while( z<zEnd && sqlite3Isdigit(*z) ){
+      e = e<10000 ? (e*10 + (*z - '0')) : 10000;
+      z+=incr;
+      eValid = 1;
     }
-    rc = !rc;
-    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (remote)\n", pFile->h, rc));
   }
-  *pResOut = rc;
-  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
-           pFile->h, pResOut, *pResOut));
-  return SQLITE_OK;
-}
-
-/*
-** Lower the locking level on file descriptor id to locktype.  locktype
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-**
-** It is not possible for this routine to fail if the second argument
-** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
-** might return SQLITE_IOERR;
-*/
-static int winUnlock(sqlite3_file *id, int locktype){
-  int type;
-  winFile *pFile = (winFile*)id;
-  int rc = SQLITE_OK;
-  assert( pFile!=0 );
-  assert( locktype<=SHARED_LOCK );
-  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
-           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
-  type = pFile->locktype;
-  if( type>=EXCLUSIVE_LOCK ){
-    winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
-    if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
-      /* This should never happen.  We should always be able to
-      ** reacquire the read lock */
-      rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
-                       "winUnlock", pFile->zPath);
-    }
-  }
-  if( type>=RESERVED_LOCK ){
-    winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
-  }
-  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
-    winUnlockReadLock(pFile);
-  }
-  if( type>=PENDING_LOCK ){
-    winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
-  }
-  pFile->locktype = (u8)locktype;
-  OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
-           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
-  return rc;
-}
 
-/*
-** If *pArg is inititially negative then this is a query.  Set *pArg to
-** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
-**
-** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
-*/
-static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
-  if( *pArg<0 ){
-    *pArg = (pFile->ctrlFlags & mask)!=0;
-  }else if( (*pArg)==0 ){
-    pFile->ctrlFlags &= ~mask;
-  }else{
-    pFile->ctrlFlags |= mask;
+  /* skip trailing spaces */
+  if( nDigits && eValid ){
+    while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
   }
-}
 
-/* Forward references to VFS helper methods used for temporary files */
-static int winGetTempname(sqlite3_vfs *, char **);
-static int winIsDir(const void *);
-static BOOL winIsDriveLetterAndColon(const char *);
+do_atof_calc:
+  /* adjust exponent by d, and update sign */
+  e = (e*esign) + d;
+  if( e<0 ) {
+    esign = -1;
+    e *= -1;
+  } else {
+    esign = 1;
+  }
 
-/*
-** Control and query of the open file handle.
-*/
-static int winFileControl(sqlite3_file *id, int op, void *pArg){
-  winFile *pFile = (winFile*)id;
-  OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
-  switch( op ){
-    case SQLITE_FCNTL_LOCKSTATE: {
-      *(int*)pArg = pFile->locktype;
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_LAST_ERRNO: {
-      *(int*)pArg = (int)pFile->lastErrno;
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_CHUNK_SIZE: {
-      pFile->szChunk = *(int *)pArg;
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
+  /* if 0 significand */
+  if( !s ) {
+    /* In the IEEE 754 standard, zero is signed.
+    ** Add the sign if we've seen at least one digit */
+    result = (sign<0 && nDigits) ? -(double)0 : (double)0;
+  } else {
+    /* attempt to reduce exponent */
+    if( esign>0 ){
+      while( s<(LARGEST_INT64/10) && e>0 ) e--,s*=10;
+    }else{
+      while( !(s%10) && e>0 ) e--,s/=10;
     }
-    case SQLITE_FCNTL_SIZE_HINT: {
-      if( pFile->szChunk>0 ){
-        sqlite3_int64 oldSz;
-        int rc = winFileSize(id, &oldSz);
-        if( rc==SQLITE_OK ){
-          sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
-          if( newSz>oldSz ){
-            SimulateIOErrorBenign(1);
-            rc = winTruncate(id, newSz);
-            SimulateIOErrorBenign(0);
-          }
+
+    /* adjust the sign of significand */
+    s = sign<0 ? -s : s;
+
+    /* if exponent, scale significand as appropriate
+    ** and store in result. */
+    if( e ){
+      LONGDOUBLE_TYPE scale = 1.0;
+      /* attempt to handle extremely small/large numbers better */
+      if( e>307 && e<342 ){
+        while( e%308 ) { scale *= 1.0e+1; e -= 1; }
+        if( esign<0 ){
+          result = s / scale;
+          result /= 1.0e+308;
+        }else{
+          result = s * scale;
+          result *= 1.0e+308;
+        }
+      }else if( e>=342 ){
+        if( esign<0 ){
+          result = 0.0*s;
+        }else{
+          result = 1e308*1e308*s;  /* Infinity */
         }
-        OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
-        return rc;
-      }
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_PERSIST_WAL: {
-      winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
-      winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_VFSNAME: {
-      *(char**)pArg = sqlite3_mprintf("win32");
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_WIN32_AV_RETRY: {
-      int *a = (int*)pArg;
-      if( a[0]>0 ){
-        winIoerrRetry = a[0];
-      }else{
-        a[0] = winIoerrRetry;
-      }
-      if( a[1]>0 ){
-        winIoerrRetryDelay = a[1];
       }else{
-        a[1] = winIoerrRetryDelay;
-      }
-      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_TEMPFILENAME: {
-      char *zTFile = 0;
-      int rc = winGetTempname(pFile->pVfs, &zTFile);
-      if( rc==SQLITE_OK ){
-        *(char**)pArg = zTFile;
-      }
-      OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
-      return rc;
-    }
-#if SQLITE_MAX_MMAP_SIZE>0
-    case SQLITE_FCNTL_MMAP_SIZE: {
-      i64 newLimit = *(i64*)pArg;
-      int rc = SQLITE_OK;
-      if( newLimit>sqlite3GlobalConfig.mxMmap ){
-        newLimit = sqlite3GlobalConfig.mxMmap;
-      }
-      *(i64*)pArg = pFile->mmapSizeMax;
-      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
-        pFile->mmapSizeMax = newLimit;
-        if( pFile->mmapSize>0 ){
-          winUnmapfile(pFile);
-          rc = winMapfile(pFile, -1);
+        /* 1.0e+22 is the largest power of 10 than can be 
+        ** represented exactly. */
+        while( e%22 ) { scale *= 1.0e+1; e -= 1; }
+        while( e>0 ) { scale *= 1.0e+22; e -= 22; }
+        if( esign<0 ){
+          result = s / scale;
+        }else{
+          result = s * scale;
         }
       }
-      OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
-      return rc;
+    } else {
+      result = (double)s;
     }
-#endif
   }
-  OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
-  return SQLITE_NOTFOUND;
-}
 
-/*
-** Return the sector size in bytes of the underlying block device for
-** the specified file. This is almost always 512 bytes, but may be
-** larger for some devices.
-**
-** SQLite code assumes this function cannot fail. It also assumes that
-** if two files are created in the same file-system directory (i.e.
-** a database and its journal file) that the sector size will be the
-** same for both.
-*/
-static int winSectorSize(sqlite3_file *id){
-  (void)id;
-  return SQLITE_DEFAULT_SECTOR_SIZE;
-}
+  /* store the result */
+  *pResult = result;
 
-/*
-** Return a vector of device characteristics.
-*/
-static int winDeviceCharacteristics(sqlite3_file *id){
-  winFile *p = (winFile*)id;
-  return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
-         ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
+  /* return true if number and no extra non-whitespace chracters after */
+  return z>=zEnd && nDigits>0 && eValid && nonNum==0;
+#else
+  return !sqlite3Atoi64(z, pResult, length, enc);
+#endif /* SQLITE_OMIT_FLOATING_POINT */
 }
 
-/* 
-** Windows will only let you create file view mappings
-** on allocation size granularity boundaries.
-** During sqlite3_os_init() we do a GetSystemInfo()
-** to get the granularity size.
-*/
-SYSTEM_INFO winSysInfo;
-
-#ifndef SQLITE_OMIT_WAL
-
 /*
-** Helper functions to obtain and relinquish the global mutex. The
-** global mutex is used to protect the winLockInfo objects used by 
-** this file, all of which may be shared by multiple threads.
+** Compare the 19-character string zNum against the text representation
+** value 2^63:  9223372036854775808.  Return negative, zero, or positive
+** if zNum is less than, equal to, or greater than the string.
+** Note that zNum must contain exactly 19 characters.
 **
-** Function winShmMutexHeld() is used to assert() that the global mutex 
-** is held when required. This function is only used as part of assert() 
-** statements. e.g.
+** Unlike memcmp() this routine is guaranteed to return the difference
+** in the values of the last digit if the only difference is in the
+** last digit.  So, for example,
 **
-**   winShmEnterMutex()
-**     assert( winShmMutexHeld() );
-**   winShmLeaveMutex()
+**      compare2pow63("9223372036854775800", 1)
+**
+** will return -8.
 */
-static void winShmEnterMutex(void){
-  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-static void winShmLeaveMutex(void){
-  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-#ifdef SQLITE_DEBUG
-static int winShmMutexHeld(void) {
-  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+static int compare2pow63(const char *zNum, int incr){
+  int c = 0;
+  int i;
+                    /* 012345678901234567 */
+  const char *pow63 = "922337203685477580";
+  for(i=0; c==0 && i<18; i++){
+    c = (zNum[i*incr]-pow63[i])*10;
+  }
+  if( c==0 ){
+    c = zNum[18*incr] - '8';
+    testcase( c==(-1) );
+    testcase( c==0 );
+    testcase( c==(+1) );
+  }
+  return c;
 }
-#endif
 
-/*
-** Object used to represent a single file opened and mmapped to provide
-** shared memory.  When multiple threads all reference the same
-** log-summary, each thread has its own winFile object, but they all
-** point to a single instance of this object.  In other words, each
-** log-summary is opened only once per process.
-**
-** winShmMutexHeld() must be true when creating or destroying
-** this object or while reading or writing the following fields:
-**
-**      nRef
-**      pNext 
-**
-** The following fields are read-only after the object is created:
-** 
-**      fid
-**      zFilename
-**
-** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
-** winShmMutexHeld() is true when reading or writing any other field
-** in this structure.
-**
-*/
-struct winShmNode {
-  sqlite3_mutex *mutex;      /* Mutex to access this object */
-  char *zFilename;           /* Name of the file */
-  winFile hFile;             /* File handle from winOpen */
-
-  int szRegion;              /* Size of shared-memory regions */
-  int nRegion;               /* Size of array apRegion */
-  struct ShmRegion {
-    HANDLE hMap;             /* File handle from CreateFileMapping */
-    void *pMap;
-  } *aRegion;
-  DWORD lastErrno;           /* The Windows errno from the last I/O error */
-
-  int nRef;                  /* Number of winShm objects pointing to this */
-  winShm *pFirst;            /* All winShm objects pointing to this */
-  winShmNode *pNext;         /* Next in list of all winShmNode objects */
-#ifdef SQLITE_DEBUG
-  u8 nextShmId;              /* Next available winShm.id value */
-#endif
-};
 
 /*
-** A global array of all winShmNode objects.
+** Convert zNum to a 64-bit signed integer.
 **
-** The winShmMutexHeld() must be true while reading or writing this list.
-*/
-static winShmNode *winShmNodeList = 0;
-
-/*
-** Structure used internally by this VFS to record the state of an
-** open shared memory connection.
+** If the zNum value is representable as a 64-bit twos-complement 
+** integer, then write that value into *pNum and return 0.
 **
-** The following fields are initialized when this object is created and
-** are read-only thereafter:
+** If zNum is exactly 9223372036854665808, return 2.  This special
+** case is broken out because while 9223372036854665808 cannot be a 
+** signed 64-bit integer, its negative -9223372036854665808 can be.
 **
-**    winShm.pShmNode
-**    winShm.id
+** If zNum is too big for a 64-bit integer and is not
+** 9223372036854665808  or if zNum contains any non-numeric text,
+** then return 1.
 **
-** All other fields are read/write.  The winShm.pShmNode->mutex must be held
-** while accessing any read/write fields.
-*/
-struct winShm {
-  winShmNode *pShmNode;      /* The underlying winShmNode object */
-  winShm *pNext;             /* Next winShm with the same winShmNode */
-  u8 hasMutex;               /* True if holding the winShmNode mutex */
-  u16 sharedMask;            /* Mask of shared locks held */
-  u16 exclMask;              /* Mask of exclusive locks held */
-#ifdef SQLITE_DEBUG
-  u8 id;                     /* Id of this connection with its winShmNode */
-#endif
-};
-
-/*
-** Constants used for locking
-*/
-#define WIN_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
-#define WIN_SHM_DMS    (WIN_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
-
-/*
-** Apply advisory locks for all n bytes beginning at ofst.
+** length is the number of bytes in the string (bytes, not characters).
+** The string is not necessarily zero-terminated.  The encoding is
+** given by enc.
 */
-#define _SHM_UNLCK  1
-#define _SHM_RDLCK  2
-#define _SHM_WRLCK  3
-static int winShmSystemLock(
-  winShmNode *pFile,    /* Apply locks to this open shared-memory segment */
-  int lockType,         /* _SHM_UNLCK, _SHM_RDLCK, or _SHM_WRLCK */
-  int ofst,             /* Offset to first byte to be locked/unlocked */
-  int nByte             /* Number of bytes to lock or unlock */
-){
-  int rc = 0;           /* Result code form Lock/UnlockFileEx() */
-
-  /* Access to the winShmNode object is serialized by the caller */
-  assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
-
-  OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
-           pFile->hFile.h, lockType, ofst, nByte));
-
-  /* Release/Acquire the system-level lock */
-  if( lockType==_SHM_UNLCK ){
-    rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
-  }else{
-    /* Initialize the locking parameters */
-    DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
-    if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
-    rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
-  }
-  
-  if( rc!= 0 ){
-    rc = SQLITE_OK;
+SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
+  int incr;
+  u64 u = 0;
+  int neg = 0; /* assume positive */
+  int i;
+  int c = 0;
+  int nonNum = 0;
+  const char *zStart;
+  const char *zEnd = zNum + length;
+  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+  if( enc==SQLITE_UTF8 ){
+    incr = 1;
   }else{
-    pFile->lastErrno =  osGetLastError();
-    rc = SQLITE_BUSY;
+    incr = 2;
+    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+    for(i=3-enc; i<length && zNum[i]==0; i+=2){}
+    nonNum = i<length;
+    zEnd = zNum+i+enc-3;
+    zNum += (enc&1);
   }
-
-  OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
-           pFile->hFile.h, (lockType == _SHM_UNLCK) ? "winUnlockFile" :
-           "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
-
-  return rc;
-}
-
-/* Forward references to VFS methods */
-static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
-static int winDelete(sqlite3_vfs *,const char*,int);
-
-/*
-** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
-**
-** This is not a VFS shared-memory method; it is a utility function called
-** by VFS shared-memory methods.
-*/
-static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
-  winShmNode **pp;
-  winShmNode *p;
-  assert( winShmMutexHeld() );
-  OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
-           osGetCurrentProcessId(), deleteFlag));
-  pp = &winShmNodeList;
-  while( (p = *pp)!=0 ){
-    if( p->nRef==0 ){
-      int i;
-      if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
-      for(i=0; i<p->nRegion; i++){
-        BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
-        OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
-                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
-        UNUSED_VARIABLE_VALUE(bRc);
-        bRc = osCloseHandle(p->aRegion[i].hMap);
-        OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
-                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
-        UNUSED_VARIABLE_VALUE(bRc);
-      }
-      if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
-        SimulateIOErrorBenign(1);
-        winClose((sqlite3_file *)&p->hFile);
-        SimulateIOErrorBenign(0);
-      }
-      if( deleteFlag ){
-        SimulateIOErrorBenign(1);
-        sqlite3BeginBenignMalloc();
-        winDelete(pVfs, p->zFilename, 0);
-        sqlite3EndBenignMalloc();
-        SimulateIOErrorBenign(0);
-      }
-      *pp = p->pNext;
-      sqlite3_free(p->aRegion);
-      sqlite3_free(p);
-    }else{
-      pp = &p->pNext;
+  while( zNum<zEnd && sqlite3Isspace(*zNum) ) zNum+=incr;
+  if( zNum<zEnd ){
+    if( *zNum=='-' ){
+      neg = 1;
+      zNum+=incr;
+    }else if( *zNum=='+' ){
+      zNum+=incr;
     }
   }
-}
-
-/*
-** Open the shared-memory area associated with database file pDbFd.
-**
-** When opening a new shared-memory file, if no other instances of that
-** file are currently open, in this process or in other processes, then
-** the file must be truncated to zero length or have its header cleared.
-*/
-static int winOpenSharedMemory(winFile *pDbFd){
-  struct winShm *p;                  /* The connection to be opened */
-  struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
-  int rc;                            /* Result code */
-  struct winShmNode *pNew;           /* Newly allocated winShmNode */
-  int nName;                         /* Size of zName in bytes */
-
-  assert( pDbFd->pShm==0 );    /* Not previously opened */
-
-  /* Allocate space for the new sqlite3_shm object.  Also speculatively
-  ** allocate space for a new winShmNode and filename.
-  */
-  p = sqlite3MallocZero( sizeof(*p) );
-  if( p==0 ) return SQLITE_IOERR_NOMEM;
-  nName = sqlite3Strlen30(pDbFd->zPath);
-  pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
-  if( pNew==0 ){
-    sqlite3_free(p);
-    return SQLITE_IOERR_NOMEM;
+  zStart = zNum;
+  while( zNum<zEnd && zNum[0]=='0' ){ zNum+=incr; } /* Skip leading zeros. */
+  for(i=0; &zNum[i]<zEnd && (c=zNum[i])>='0' && c<='9'; i+=incr){
+    u = u*10 + c - '0';
   }
-  pNew->zFilename = (char*)&pNew[1];
-  sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
-  sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename); 
-
-  /* Look to see if there is an existing winShmNode that can be used.
-  ** If no matching winShmNode currently exists, create a new one.
-  */
-  winShmEnterMutex();
-  for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
-    /* TBD need to come up with better match here.  Perhaps
-    ** use FILE_ID_BOTH_DIR_INFO Structure.
-    */
-    if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
+  if( u>LARGEST_INT64 ){
+    *pNum = SMALLEST_INT64;
+  }else if( neg ){
+    *pNum = -(i64)u;
+  }else{
+    *pNum = (i64)u;
   }
-  if( pShmNode ){
-    sqlite3_free(pNew);
+  testcase( i==18 );
+  testcase( i==19 );
+  testcase( i==20 );
+  if( (c!=0 && &zNum[i]<zEnd) || (i==0 && zStart==zNum) || i>19*incr || nonNum ){
+    /* zNum is empty or contains non-numeric text or is longer
+    ** than 19 digits (thus guaranteeing that it is too large) */
+    return 1;
+  }else if( i<19*incr ){
+    /* Less than 19 digits, so we know that it fits in 64 bits */
+    assert( u<=LARGEST_INT64 );
+    return 0;
   }else{
-    pShmNode = pNew;
-    pNew = 0;
-    ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
-    pShmNode->pNext = winShmNodeList;
-    winShmNodeList = pShmNode;
-
-    pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
-    if( pShmNode->mutex==0 ){
-      rc = SQLITE_IOERR_NOMEM;
-      goto shm_open_err;
-    }
-
-    rc = winOpen(pDbFd->pVfs,
-                 pShmNode->zFilename,             /* Name of the file (UTF-8) */
-                 (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
-                 SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
-                 0);
-    if( SQLITE_OK!=rc ){
-      goto shm_open_err;
-    }
-
-    /* Check to see if another process is holding the dead-man switch.
-    ** If not, truncate the file to zero length. 
-    */
-    if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
-      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
-      if( rc!=SQLITE_OK ){
-        rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
-                         "winOpenShm", pDbFd->zPath);
-      }
-    }
-    if( rc==SQLITE_OK ){
-      winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
-      rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
+    /* zNum is a 19-digit numbers.  Compare it against 9223372036854775808. */
+    c = compare2pow63(zNum, incr);
+    if( c<0 ){
+      /* zNum is less than 9223372036854775808 so it fits */
+      assert( u<=LARGEST_INT64 );
+      return 0;
+    }else if( c>0 ){
+      /* zNum is greater than 9223372036854775808 so it overflows */
+      return 1;
+    }else{
+      /* zNum is exactly 9223372036854775808.  Fits if negative.  The
+      ** special case 2 overflow if positive */
+      assert( u-1==LARGEST_INT64 );
+      assert( (*pNum)==SMALLEST_INT64 );
+      return neg ? 0 : 2;
     }
-    if( rc ) goto shm_open_err;
-  }
-
-  /* Make the new connection a child of the winShmNode */
-  p->pShmNode = pShmNode;
-#ifdef SQLITE_DEBUG
-  p->id = pShmNode->nextShmId++;
-#endif
-  pShmNode->nRef++;
-  pDbFd->pShm = p;
-  winShmLeaveMutex();
-
-  /* The reference count on pShmNode has already been incremented under
-  ** the cover of the winShmEnterMutex() mutex and the pointer from the
-  ** new (struct winShm) object to the pShmNode has been set. All that is
-  ** left to do is to link the new object into the linked list starting
-  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
-  ** mutex.
-  */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  p->pNext = pShmNode->pFirst;
-  pShmNode->pFirst = p;
-  sqlite3_mutex_leave(pShmNode->mutex);
-  return SQLITE_OK;
-
-  /* Jump here on any error */
-shm_open_err:
-  winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
-  winShmPurge(pDbFd->pVfs, 0);      /* This call frees pShmNode if required */
-  sqlite3_free(p);
-  sqlite3_free(pNew);
-  winShmLeaveMutex();
-  return rc;
+  }
 }
 
 /*
-** Close a connection to shared-memory.  Delete the underlying 
-** storage if deleteFlag is true.
+** If zNum represents an integer that will fit in 32-bits, then set
+** *pValue to that integer and return true.  Otherwise return false.
+**
+** Any non-numeric characters that following zNum are ignored.
+** This is different from sqlite3Atoi64() which requires the
+** input number to be zero-terminated.
 */
-static int winShmUnmap(
-  sqlite3_file *fd,          /* Database holding shared memory */
-  int deleteFlag             /* Delete after closing if true */
-){
-  winFile *pDbFd;       /* Database holding shared-memory */
-  winShm *p;            /* The connection to be closed */
-  winShmNode *pShmNode; /* The underlying shared-memory file */
-  winShm **pp;          /* For looping over sibling connections */
-
-  pDbFd = (winFile*)fd;
-  p = pDbFd->pShm;
-  if( p==0 ) return SQLITE_OK;
-  pShmNode = p->pShmNode;
-
-  /* Remove connection p from the set of connections associated
-  ** with pShmNode */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
-  *pp = p->pNext;
-
-  /* Free the connection p */
-  sqlite3_free(p);
-  pDbFd->pShm = 0;
-  sqlite3_mutex_leave(pShmNode->mutex);
-
-  /* If pShmNode->nRef has reached 0, then close the underlying
-  ** shared-memory file, too */
-  winShmEnterMutex();
-  assert( pShmNode->nRef>0 );
-  pShmNode->nRef--;
-  if( pShmNode->nRef==0 ){
-    winShmPurge(pDbFd->pVfs, deleteFlag);
+SQLITE_PRIVATE int sqlite3GetInt32(const char *zNum, int *pValue){
+  sqlite_int64 v = 0;
+  int i, c;
+  int neg = 0;
+  if( zNum[0]=='-' ){
+    neg = 1;
+    zNum++;
+  }else if( zNum[0]=='+' ){
+    zNum++;
+  }
+  while( zNum[0]=='0' ) zNum++;
+  for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){
+    v = v*10 + c;
   }
-  winShmLeaveMutex();
 
-  return SQLITE_OK;
+  /* The longest decimal representation of a 32 bit integer is 10 digits:
+  **
+  **             1234567890
+  **     2^31 -> 2147483648
+  */
+  testcase( i==10 );
+  if( i>10 ){
+    return 0;
+  }
+  testcase( v-neg==2147483647 );
+  if( v-neg>2147483647 ){
+    return 0;
+  }
+  if( neg ){
+    v = -v;
+  }
+  *pValue = (int)v;
+  return 1;
 }
 
 /*
-** Change the lock state for a shared-memory segment.
+** Return a 32-bit integer value extracted from a string.  If the
+** string is not an integer, just return 0.
 */
-static int winShmLock(
-  sqlite3_file *fd,          /* Database file holding the shared memory */
-  int ofst,                  /* First lock to acquire or release */
-  int n,                     /* Number of locks to acquire or release */
-  int flags                  /* What to do with the lock */
-){
-  winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
-  winShm *p = pDbFd->pShm;              /* The shared memory being locked */
-  winShm *pX;                           /* For looping over all siblings */
-  winShmNode *pShmNode = p->pShmNode;
-  int rc = SQLITE_OK;                   /* Result code */
-  u16 mask;                             /* Mask of locks to take or release */
-
-  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
-  assert( n>=1 );
-  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
-  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
-
-  mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
-  assert( n>1 || mask==(1<<ofst) );
-  sqlite3_mutex_enter(pShmNode->mutex);
-  if( flags & SQLITE_SHM_UNLOCK ){
-    u16 allMask = 0; /* Mask of locks held by siblings */
-
-    /* See if any siblings hold this same lock */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( pX==p ) continue;
-      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
-      allMask |= pX->sharedMask;
-    }
-
-    /* Unlock the system-level locks */
-    if( (mask & allMask)==0 ){
-      rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
-    }else{
-      rc = SQLITE_OK;
-    }
-
-    /* Undo the local locks */
-    if( rc==SQLITE_OK ){
-      p->exclMask &= ~mask;
-      p->sharedMask &= ~mask;
-    } 
-  }else if( flags & SQLITE_SHM_SHARED ){
-    u16 allShared = 0;  /* Union of locks held by connections other than "p" */
-
-    /* Find out which shared locks are already held by sibling connections.
-    ** If any sibling already holds an exclusive lock, go ahead and return
-    ** SQLITE_BUSY.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-      allShared |= pX->sharedMask;
-    }
-
-    /* Get shared locks at the system level, if necessary */
-    if( rc==SQLITE_OK ){
-      if( (allShared & mask)==0 ){
-        rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
-      }else{
-        rc = SQLITE_OK;
-      }
-    }
-
-    /* Get the local shared locks */
-    if( rc==SQLITE_OK ){
-      p->sharedMask |= mask;
-    }
-  }else{
-    /* Make sure no sibling connections hold locks that will block this
-    ** lock.  If any do, return SQLITE_BUSY right away.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-    }
-  
-    /* Get the exclusive locks at the system level.  Then if successful
-    ** also mark the local connection as being locked.
-    */
-    if( rc==SQLITE_OK ){
-      rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
-      if( rc==SQLITE_OK ){
-        assert( (p->sharedMask & mask)==0 );
-        p->exclMask |= mask;
-      }
-    }
-  }
-  sqlite3_mutex_leave(pShmNode->mutex);
-  OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
-           osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
-           sqlite3ErrName(rc)));
-  return rc;
+SQLITE_PRIVATE int sqlite3Atoi(const char *z){
+  int x = 0;
+  if( z ) sqlite3GetInt32(z, &x);
+  return x;
 }
 
 /*
-** Implement a memory barrier or memory fence on shared memory.  
+** The variable-length integer encoding is as follows:
+**
+** KEY:
+**         A = 0xxxxxxx    7 bits of data and one flag bit
+**         B = 1xxxxxxx    7 bits of data and one flag bit
+**         C = xxxxxxxx    8 bits of data
 **
-** All loads and stores begun before the barrier must complete before
-** any load or store begun after the barrier.
+**  7 bits - A
+** 14 bits - BA
+** 21 bits - BBA
+** 28 bits - BBBA
+** 35 bits - BBBBA
+** 42 bits - BBBBBA
+** 49 bits - BBBBBBA
+** 56 bits - BBBBBBBA
+** 64 bits - BBBBBBBBC
 */
-static void winShmBarrier(
-  sqlite3_file *fd          /* Database holding the shared memory */
-){
-  UNUSED_PARAMETER(fd);
-  /* MemoryBarrier(); // does not work -- do not know why not */
-  winShmEnterMutex();
-  winShmLeaveMutex();
-}
 
 /*
-** This function is called to obtain a pointer to region iRegion of the 
-** shared-memory associated with the database file fd. Shared-memory regions 
-** are numbered starting from zero. Each shared-memory region is szRegion 
-** bytes in size.
-**
-** If an error occurs, an error code is returned and *pp is set to NULL.
-**
-** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
-** region has not been allocated (by any client, including one running in a
-** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
-** isWrite is non-zero and the requested shared-memory region has not yet 
-** been allocated, it is allocated by this function.
+** Write a 64-bit variable-length integer to memory starting at p[0].
+** The length of data write will be between 1 and 9 bytes.  The number
+** of bytes written is returned.
 **
-** If the shared-memory region has already been allocated or is allocated by
-** this call as described above, then it is mapped into this processes 
-** address space (if it is not already), *pp is set to point to the mapped 
-** memory and SQLITE_OK returned.
+** A variable-length integer consists of the lower 7 bits of each byte
+** for all bytes that have the 8th bit set and one byte with the 8th
+** bit clear.  Except, if we get to the 9th byte, it stores the full
+** 8 bits and is the last byte.
 */
-static int winShmMap(
-  sqlite3_file *fd,               /* Handle open on database file */
-  int iRegion,                    /* Region to retrieve */
-  int szRegion,                   /* Size of regions */
-  int isWrite,                    /* True to extend file if necessary */
-  void volatile **pp              /* OUT: Mapped memory */
-){
-  winFile *pDbFd = (winFile*)fd;
-  winShm *p = pDbFd->pShm;
-  winShmNode *pShmNode;
-  int rc = SQLITE_OK;
-
-  if( !p ){
-    rc = winOpenSharedMemory(pDbFd);
-    if( rc!=SQLITE_OK ) return rc;
-    p = pDbFd->pShm;
-  }
-  pShmNode = p->pShmNode;
-
-  sqlite3_mutex_enter(pShmNode->mutex);
-  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
-
-  if( pShmNode->nRegion<=iRegion ){
-    struct ShmRegion *apNew;           /* New aRegion[] array */
-    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
-    sqlite3_int64 sz;                  /* Current size of wal-index file */
-
-    pShmNode->szRegion = szRegion;
-
-    /* The requested region is not mapped into this processes address space.
-    ** Check to see if it has been allocated (i.e. if the wal-index file is
-    ** large enough to contain the requested region).
-    */
-    rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
-    if( rc!=SQLITE_OK ){
-      rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
-                       "winShmMap1", pDbFd->zPath);
-      goto shmpage_out;
-    }
-
-    if( sz<nByte ){
-      /* The requested memory region does not exist. If isWrite is set to
-      ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
-      **
-      ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
-      ** the requested memory region.
-      */
-      if( !isWrite ) goto shmpage_out;
-      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
-      if( rc!=SQLITE_OK ){
-        rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
-                         "winShmMap2", pDbFd->zPath);
-        goto shmpage_out;
-      }
-    }
-
-    /* Map the requested memory region into this processes address space. */
-    apNew = (struct ShmRegion *)sqlite3_realloc(
-        pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
-    );
-    if( !apNew ){
-      rc = SQLITE_IOERR_NOMEM;
-      goto shmpage_out;
-    }
-    pShmNode->aRegion = apNew;
-
-    while( pShmNode->nRegion<=iRegion ){
-      HANDLE hMap = NULL;         /* file-mapping handle */
-      void *pMap = 0;             /* Mapped memory region */
-     
-#if SQLITE_OS_WINRT
-      hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
-          NULL, PAGE_READWRITE, nByte, NULL
-      );
-#elif defined(SQLITE_WIN32_HAS_WIDE)
-      hMap = osCreateFileMappingW(pShmNode->hFile.h, 
-          NULL, PAGE_READWRITE, 0, nByte, NULL
-      );
-#elif defined(SQLITE_WIN32_HAS_ANSI)
-      hMap = osCreateFileMappingA(pShmNode->hFile.h, 
-          NULL, PAGE_READWRITE, 0, nByte, NULL
-      );
-#endif
-      OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
-               osGetCurrentProcessId(), pShmNode->nRegion, nByte,
-               hMap ? "ok" : "failed"));
-      if( hMap ){
-        int iOffset = pShmNode->nRegion*szRegion;
-        int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
-#if SQLITE_OS_WINRT
-        pMap = osMapViewOfFileFromApp(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
-            iOffset - iOffsetShift, szRegion + iOffsetShift
-        );
-#else
-        pMap = osMapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
-            0, iOffset - iOffsetShift, szRegion + iOffsetShift
-        );
-#endif
-        OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
-                 osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
-                 szRegion, pMap ? "ok" : "failed"));
-      }
-      if( !pMap ){
-        pShmNode->lastErrno = osGetLastError();
-        rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
-                         "winShmMap3", pDbFd->zPath);
-        if( hMap ) osCloseHandle(hMap);
-        goto shmpage_out;
-      }
-
-      pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
-      pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
-      pShmNode->nRegion++;
+SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
+  int i, j, n;
+  u8 buf[10];
+  if( v & (((u64)0xff000000)<<32) ){
+    p[8] = (u8)v;
+    v >>= 8;
+    for(i=7; i>=0; i--){
+      p[i] = (u8)((v & 0x7f) | 0x80);
+      v >>= 7;
     }
+    return 9;
+  }    
+  n = 0;
+  do{
+    buf[n++] = (u8)((v & 0x7f) | 0x80);
+    v >>= 7;
+  }while( v!=0 );
+  buf[0] &= 0x7f;
+  assert( n<=9 );
+  for(i=0, j=n-1; j>=0; j--, i++){
+    p[i] = buf[j];
   }
-
-shmpage_out:
-  if( pShmNode->nRegion>iRegion ){
-    int iOffset = iRegion*szRegion;
-    int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
-    char *p = (char *)pShmNode->aRegion[iRegion].pMap;
-    *pp = (void *)&p[iOffsetShift];
-  }else{
-    *pp = 0;
-  }
-  sqlite3_mutex_leave(pShmNode->mutex);
-  return rc;
+  return n;
 }
 
-#else
-# define winShmMap     0
-# define winShmLock    0
-# define winShmBarrier 0
-# define winShmUnmap   0
-#endif /* #ifndef SQLITE_OMIT_WAL */
-
 /*
-** Cleans up the mapped region of the specified file, if any.
+** This routine is a faster version of sqlite3PutVarint() that only
+** works for 32-bit positive integers and which is optimized for
+** the common case of small integers.  A MACRO version, putVarint32,
+** is provided which inlines the single-byte case.  All code should use
+** the MACRO version as this function assumes the single-byte case has
+** already been handled.
 */
-#if SQLITE_MAX_MMAP_SIZE>0
-static int winUnmapfile(winFile *pFile){
-  assert( pFile!=0 );
-  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
-           "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
-           osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
-           pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
-  if( pFile->pMapRegion ){
-    if( !osUnmapViewOfFile(pFile->pMapRegion) ){
-      pFile->lastErrno = osGetLastError();
-      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
-               "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
-               pFile->pMapRegion));
-      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
-                         "winUnmapfile1", pFile->zPath);
-    }
-    pFile->pMapRegion = 0;
-    pFile->mmapSize = 0;
-    pFile->mmapSizeActual = 0;
-  }
-  if( pFile->hMap!=NULL ){
-    if( !osCloseHandle(pFile->hMap) ){
-      pFile->lastErrno = osGetLastError();
-      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
-               osGetCurrentProcessId(), pFile, pFile->hMap));
-      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
-                         "winUnmapfile2", pFile->zPath);
-    }
-    pFile->hMap = NULL;
-  }
-  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
-           osGetCurrentProcessId(), pFile));
-  return SQLITE_OK;
+SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char *p, u32 v){
+#ifndef putVarint32
+  if( (v & ~0x7f)==0 ){
+    p[0] = v;
+    return 1;
+  }
+#endif
+  if( (v & ~0x3fff)==0 ){
+    p[0] = (u8)((v>>7) | 0x80);
+    p[1] = (u8)(v & 0x7f);
+    return 2;
+  }
+  return sqlite3PutVarint(p, v);
 }
 
 /*
-** Memory map or remap the file opened by file-descriptor pFd (if the file
-** is already mapped, the existing mapping is replaced by the new). Or, if 
-** there already exists a mapping for this file, and there are still 
-** outstanding xFetch() references to it, this function is a no-op.
+** Bitmasks used by sqlite3GetVarint().  These precomputed constants
+** are defined here rather than simply putting the constant expressions
+** inline in order to work around bugs in the RVT compiler.
 **
-** If parameter nByte is non-negative, then it is the requested size of 
-** the mapping to create. Otherwise, if nByte is less than zero, then the 
-** requested size is the size of the file on disk. The actual size of the
-** created mapping is either the requested size or the value configured 
-** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
+** SLOT_2_0     A mask for  (0x7f<<14) | 0x7f
 **
-** SQLITE_OK is returned if no error occurs (even if the mapping is not
-** recreated as a result of outstanding references) or an SQLite error
-** code otherwise.
+** SLOT_4_2_0   A mask for  (0x7f<<28) | SLOT_2_0
 */
-static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
-  sqlite3_int64 nMap = nByte;
-  int rc;
+#define SLOT_2_0     0x001fc07f
+#define SLOT_4_2_0   0xf01fc07f
 
-  assert( nMap>=0 || pFd->nFetchOut==0 );
-  OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
-           osGetCurrentProcessId(), pFd, nByte));
 
-  if( pFd->nFetchOut>0 ) return SQLITE_OK;
+/*
+** Read a 64-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read.  The value is stored in *v.
+*/
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
+  u32 a,b,s;
 
-  if( nMap<0 ){
-    rc = winFileSize((sqlite3_file*)pFd, &nMap);
-    if( rc ){
-      OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
-               osGetCurrentProcessId(), pFd));
-      return SQLITE_IOERR_FSTAT;
-    }
-  }
-  if( nMap>pFd->mmapSizeMax ){
-    nMap = pFd->mmapSizeMax;
-  }
-  nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
- 
-  if( nMap==0 && pFd->mmapSize>0 ){
-    winUnmapfile(pFd);
-  }
-  if( nMap!=pFd->mmapSize ){
-    void *pNew = 0;
-    DWORD protect = PAGE_READONLY;
-    DWORD flags = FILE_MAP_READ;
-
-    winUnmapfile(pFd);
-    if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
-      protect = PAGE_READWRITE;
-      flags |= FILE_MAP_WRITE;
-    }
-#if SQLITE_OS_WINRT
-    pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
-#elif defined(SQLITE_WIN32_HAS_WIDE)
-    pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
-                                (DWORD)((nMap>>32) & 0xffffffff),
-                                (DWORD)(nMap & 0xffffffff), NULL);
-#elif defined(SQLITE_WIN32_HAS_ANSI)
-    pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
-                                (DWORD)((nMap>>32) & 0xffffffff),
-                                (DWORD)(nMap & 0xffffffff), NULL);
-#endif
-    if( pFd->hMap==NULL ){
-      pFd->lastErrno = osGetLastError();
-      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
-                       "winMapfile1", pFd->zPath);
-      /* Log the error, but continue normal operation using xRead/xWrite */
-      OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
-               osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
-      return SQLITE_OK;
-    }
-    assert( (nMap % winSysInfo.dwPageSize)==0 );
-    assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
-#if SQLITE_OS_WINRT
-    pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
-#else
-    pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
-#endif
-    if( pNew==NULL ){
-      osCloseHandle(pFd->hMap);
-      pFd->hMap = NULL;
-      pFd->lastErrno = osGetLastError();
-      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
-                       "winMapfile2", pFd->zPath);
-      /* Log the error, but continue normal operation using xRead/xWrite */
-      OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
-               osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
-      return SQLITE_OK;
-    }
-    pFd->pMapRegion = pNew;
-    pFd->mmapSize = nMap;
-    pFd->mmapSizeActual = nMap;
+  a = *p;
+  /* a: p0 (unmasked) */
+  if (!(a&0x80))
+  {
+    *v = a;
+    return 1;
   }
 
-  OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
-           osGetCurrentProcessId(), pFd));
-  return SQLITE_OK;
-}
-#endif /* SQLITE_MAX_MMAP_SIZE>0 */
-
-/*
-** If possible, return a pointer to a mapping of file fd starting at offset
-** iOff. The mapping must be valid for at least nAmt bytes.
-**
-** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
-** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
-** Finally, if an error does occur, return an SQLite error code. The final
-** value of *pp is undefined in this case.
-**
-** If this function does return a pointer, the caller must eventually 
-** release the reference by calling winUnfetch().
-*/
-static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
-#if SQLITE_MAX_MMAP_SIZE>0
-  winFile *pFd = (winFile*)fd;   /* The underlying database file */
-#endif
-  *pp = 0;
+  p++;
+  b = *p;
+  /* b: p1 (unmasked) */
+  if (!(b&0x80))
+  {
+    a &= 0x7f;
+    a = a<<7;
+    a |= b;
+    *v = a;
+    return 2;
+  }
 
-  OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
-           osGetCurrentProcessId(), fd, iOff, nAmt, pp));
+  /* Verify that constants are precomputed correctly */
+  assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) );
+  assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) );
 
-#if SQLITE_MAX_MMAP_SIZE>0
-  if( pFd->mmapSizeMax>0 ){
-    if( pFd->pMapRegion==0 ){
-      int rc = winMapfile(pFd, -1);
-      if( rc!=SQLITE_OK ){
-        OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
-                 osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
-        return rc;
-      }
-    }
-    if( pFd->mmapSize >= iOff+nAmt ){
-      *pp = &((u8 *)pFd->pMapRegion)[iOff];
-      pFd->nFetchOut++;
-    }
+  p++;
+  a = a<<14;
+  a |= *p;
+  /* a: p0<<14 | p2 (unmasked) */
+  if (!(a&0x80))
+  {
+    a &= SLOT_2_0;
+    b &= 0x7f;
+    b = b<<7;
+    a |= b;
+    *v = a;
+    return 3;
   }
-#endif
 
-  OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
-           osGetCurrentProcessId(), fd, pp, *pp));
-  return SQLITE_OK;
-}
+  /* CSE1 from below */
+  a &= SLOT_2_0;
+  p++;
+  b = b<<14;
+  b |= *p;
+  /* b: p1<<14 | p3 (unmasked) */
+  if (!(b&0x80))
+  {
+    b &= SLOT_2_0;
+    /* moved CSE1 up */
+    /* a &= (0x7f<<14)|(0x7f); */
+    a = a<<7;
+    a |= b;
+    *v = a;
+    return 4;
+  }
 
-/*
-** If the third argument is non-NULL, then this function releases a 
-** reference obtained by an earlier call to winFetch(). The second
-** argument passed to this function must be the same as the corresponding
-** argument that was passed to the winFetch() invocation. 
-**
-** Or, if the third argument is NULL, then this function is being called 
-** to inform the VFS layer that, according to POSIX, any existing mapping 
-** may now be invalid and should be unmapped.
-*/
-static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
-#if SQLITE_MAX_MMAP_SIZE>0
-  winFile *pFd = (winFile*)fd;   /* The underlying database file */
+  /* a: p0<<14 | p2 (masked) */
+  /* b: p1<<14 | p3 (unmasked) */
+  /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+  /* moved CSE1 up */
+  /* a &= (0x7f<<14)|(0x7f); */
+  b &= SLOT_2_0;
+  s = a;
+  /* s: p0<<14 | p2 (masked) */
 
-  /* If p==0 (unmap the entire file) then there must be no outstanding 
-  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
-  ** then there must be at least one outstanding.  */
-  assert( (p==0)==(pFd->nFetchOut==0) );
+  p++;
+  a = a<<14;
+  a |= *p;
+  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+  if (!(a&0x80))
+  {
+    /* we can skip these cause they were (effectively) done above in calc'ing s */
+    /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+    /* b &= (0x7f<<14)|(0x7f); */
+    b = b<<7;
+    a |= b;
+    s = s>>18;
+    *v = ((u64)s)<<32 | a;
+    return 5;
+  }
 
-  /* If p!=0, it must match the iOff value. */
-  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+  /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+  s = s<<7;
+  s |= b;
+  /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
 
-  OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
-           osGetCurrentProcessId(), pFd, iOff, p));
+  p++;
+  b = b<<14;
+  b |= *p;
+  /* b: p1<<28 | p3<<14 | p5 (unmasked) */
+  if (!(b&0x80))
+  {
+    /* we can skip this cause it was (effectively) done above in calc'ing s */
+    /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+    a &= SLOT_2_0;
+    a = a<<7;
+    a |= b;
+    s = s>>18;
+    *v = ((u64)s)<<32 | a;
+    return 6;
+  }
 
-  if( p ){
-    pFd->nFetchOut--;
-  }else{
-    /* FIXME:  If Windows truly always prevents truncating or deleting a
-    ** file while a mapping is held, then the following winUnmapfile() call
-    ** is unnecessary can can be omitted - potentially improving
-    ** performance.  */
-    winUnmapfile(pFd);
+  p++;
+  a = a<<14;
+  a |= *p;
+  /* a: p2<<28 | p4<<14 | p6 (unmasked) */
+  if (!(a&0x80))
+  {
+    a &= SLOT_4_2_0;
+    b &= SLOT_2_0;
+    b = b<<7;
+    a |= b;
+    s = s>>11;
+    *v = ((u64)s)<<32 | a;
+    return 7;
   }
 
-  assert( pFd->nFetchOut>=0 );
-#endif
+  /* CSE2 from below */
+  a &= SLOT_2_0;
+  p++;
+  b = b<<14;
+  b |= *p;
+  /* b: p3<<28 | p5<<14 | p7 (unmasked) */
+  if (!(b&0x80))
+  {
+    b &= SLOT_4_2_0;
+    /* moved CSE2 up */
+    /* a &= (0x7f<<14)|(0x7f); */
+    a = a<<7;
+    a |= b;
+    s = s>>4;
+    *v = ((u64)s)<<32 | a;
+    return 8;
+  }
 
-  OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
-           osGetCurrentProcessId(), fd));
-  return SQLITE_OK;
-}
+  p++;
+  a = a<<15;
+  a |= *p;
+  /* a: p4<<29 | p6<<15 | p8 (unmasked) */
 
-/*
-** Here ends the implementation of all sqlite3_file methods.
-**
-********************** End sqlite3_file Methods *******************************
-******************************************************************************/
+  /* moved CSE2 up */
+  /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
+  b &= SLOT_2_0;
+  b = b<<8;
+  a |= b;
 
-/*
-** This vector defines all the methods that can operate on an
-** sqlite3_file for win32.
-*/
-static const sqlite3_io_methods winIoMethod = {
-  3,                              /* iVersion */
-  winClose,                       /* xClose */
-  winRead,                        /* xRead */
-  winWrite,                       /* xWrite */
-  winTruncate,                    /* xTruncate */
-  winSync,                        /* xSync */
-  winFileSize,                    /* xFileSize */
-  winLock,                        /* xLock */
-  winUnlock,                      /* xUnlock */
-  winCheckReservedLock,           /* xCheckReservedLock */
-  winFileControl,                 /* xFileControl */
-  winSectorSize,                  /* xSectorSize */
-  winDeviceCharacteristics,       /* xDeviceCharacteristics */
-  winShmMap,                      /* xShmMap */
-  winShmLock,                     /* xShmLock */
-  winShmBarrier,                  /* xShmBarrier */
-  winShmUnmap,                    /* xShmUnmap */
-  winFetch,                       /* xFetch */
-  winUnfetch                      /* xUnfetch */
-};
+  s = s<<4;
+  b = p[-4];
+  b &= 0x7f;
+  b = b>>3;
+  s |= b;
 
-/****************************************************************************
-**************************** sqlite3_vfs methods ****************************
-**
-** This division contains the implementation of methods on the
-** sqlite3_vfs object.
-*/
+  *v = ((u64)s)<<32 | a;
 
-#if 0
-/*
-** Convert a filename from whatever the underlying operating system
-** supports for filenames into UTF-8.  Space to hold the result is
-** obtained from malloc and must be freed by the calling function.
-*/
-static char *winConvertToUtf8Filename(const void *zFilename){
-  char *zConverted = 0;
-  if( osIsNT() ){
-    zConverted = winUnicodeToUtf8(zFilename);
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    zConverted = sqlite3_win32_mbcs_to_utf8(zFilename);
-  }
-#endif
-  /* caller will handle out of memory */
-  return zConverted;
+  return 9;
 }
-#endif
 
 /*
-** Convert a UTF-8 filename into whatever form the underlying
-** operating system wants filenames in.  Space to hold the result
-** is obtained from malloc and must be freed by the calling
-** function.
+** Read a 32-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read.  The value is stored in *v.
+**
+** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
+** integer, then set *v to 0xffffffff.
+**
+** A MACRO version, getVarint32, is provided which inlines the 
+** single-byte case.  All code should use the MACRO version as 
+** this function assumes the single-byte case has already been handled.
 */
-static void *winConvertFromUtf8Filename(const char *zFilename){
-  void *zConverted = 0;
-  if( osIsNT() ){
-    zConverted = winUtf8ToUnicode(zFilename);
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
-  }
-#endif
-  /* caller will handle out of memory */
-  return zConverted;
-}
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
+  u32 a,b;
 
-/*
-** This function returns non-zero if the specified UTF-8 string buffer
-** ends with a directory separator character.
-*/
-static int winEndsInDirSep(char *zBuf){
-  if( zBuf ){
-    int nLen = sqlite3Strlen30(zBuf);
-    return nLen>0 && winIsDirSep(zBuf[nLen-1]);
+  /* The 1-byte case.  Overwhelmingly the most common.  Handled inline
+  ** by the getVarin32() macro */
+  a = *p;
+  /* a: p0 (unmasked) */
+#ifndef getVarint32
+  if (!(a&0x80))
+  {
+    /* Values between 0 and 127 */
+    *v = a;
+    return 1;
   }
-  return 0;
-}
-
-/*
-** Create a temporary file name and store the resulting pointer into pzBuf.
-** The pointer returned in pzBuf must be freed via sqlite3_free().
-*/
-static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
-  static char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  size_t i, j;
-  int nBuf, nLen;
-  char *zBuf;
-
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. 
-  */
-  SimulateIOError( return SQLITE_IOERR );
+#endif
 
-  /* Allocate a temporary buffer to store the fully qualified file
-  ** name for the temporary file.  If this fails, we cannot continue.
-  */
-  nBuf = pVfs->mxPathname;
-  zBuf = sqlite3MallocZero( nBuf+2 );
-  if( !zBuf ){
-    OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-    return SQLITE_IOERR_NOMEM;
+  /* The 2-byte case */
+  p++;
+  b = *p;
+  /* b: p1 (unmasked) */
+  if (!(b&0x80))
+  {
+    /* Values between 128 and 16383 */
+    a &= 0x7f;
+    a = a<<7;
+    *v = a | b;
+    return 2;
   }
 
-  /* Figure out the effective temporary directory.  First, check if one
-  ** has been explicitly set by the application; otherwise, use the one
-  ** configured by the operating system.
-  */
-  assert( nBuf>30 );
-  if( sqlite3_temp_directory ){
-    sqlite3_snprintf(nBuf-30, zBuf, "%s%s", sqlite3_temp_directory,
-                     winEndsInDirSep(sqlite3_temp_directory) ? "" :
-                     winGetDirDep());
-  }
-#if defined(__CYGWIN__)
-  else{
-    static const char *azDirs[] = {
-       0, /* getenv("SQLITE_TMPDIR") */
-       0, /* getenv("TMPDIR") */
-       0, /* getenv("TMP") */
-       0, /* getenv("TEMP") */
-       0, /* getenv("USERPROFILE") */
-       "/var/tmp",
-       "/usr/tmp",
-       "/tmp",
-       ".",
-       0        /* List terminator */
-    };
-    unsigned int i;
-    const char *zDir = 0;
-
-    if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
-    if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
-    if( !azDirs[2] ) azDirs[2] = getenv("TMP");
-    if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
-    if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
-    for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
-      void *zConverted;
-      if( zDir==0 ) continue;
-      /* If the path starts with a drive letter followed by the colon
-      ** character, assume it is already a native Win32 path; otherwise,
-      ** it must be converted to a native Win32 path prior via the Cygwin
-      ** API prior to using it.
-      */
-      if( winIsDriveLetterAndColon(zDir) ){
-        zConverted = winConvertFromUtf8Filename(zDir);
-        if( !zConverted ){
-          sqlite3_free(zBuf);
-          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-          return SQLITE_IOERR_NOMEM;
-        }
-        if( winIsDir(zConverted) ){
-          sqlite3_snprintf(nBuf-30, zBuf, "%s", zDir);
-          sqlite3_free(zConverted);
-          break;
-        }
-        sqlite3_free(zConverted);
-      }else{
-        zConverted = sqlite3MallocZero( nBuf+1 );
-        if( !zConverted ){
-          sqlite3_free(zBuf);
-          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-          return SQLITE_IOERR_NOMEM;
-        }
-        if( cygwin_conv_path(
-                osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A, zDir,
-                zConverted, nBuf+1)<0 ){
-          sqlite3_free(zConverted);
-          sqlite3_free(zBuf);
-          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_CONVPATH\n"));
-          return winLogError(SQLITE_IOERR_CONVPATH, (DWORD)errno,
-                             "winGetTempname1", zDir);
-        }
-        if( winIsDir(zConverted) ){
-          /* At this point, we know the candidate directory exists and should
-          ** be used.  However, we may need to convert the string containing
-          ** its name into UTF-8 (i.e. if it is UTF-16 right now).
-          */
-          if( osIsNT() ){
-            char *zUtf8 = winUnicodeToUtf8(zConverted);
-            if( !zUtf8 ){
-              sqlite3_free(zConverted);
-              sqlite3_free(zBuf);
-              OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-              return SQLITE_IOERR_NOMEM;
-            }
-            sqlite3_snprintf(nBuf-30, zBuf, "%s", zUtf8);
-            sqlite3_free(zUtf8);
-            sqlite3_free(zConverted);
-            break;
-          }else{
-            sqlite3_snprintf(nBuf-30, zBuf, "%s", zConverted);
-            sqlite3_free(zConverted);
-            break;
-          }
-        }
-        sqlite3_free(zConverted);
-      }
-    }
-  }
-#elif !SQLITE_OS_WINRT && !defined(__CYGWIN__)
-  else if( osIsNT() ){
-    char *zMulti;
-    LPWSTR zWidePath = sqlite3MallocZero( nBuf*sizeof(WCHAR) );
-    if( !zWidePath ){
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-      return SQLITE_IOERR_NOMEM;
-    }
-    if( osGetTempPathW(nBuf, zWidePath)==0 ){
-      sqlite3_free(zWidePath);
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
-      return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
-                         "winGetTempname1", 0);
-    }
-    zMulti = winUnicodeToUtf8(zWidePath);
-    if( zMulti ){
-      sqlite3_snprintf(nBuf-30, zBuf, "%s", zMulti);
-      sqlite3_free(zMulti);
-      sqlite3_free(zWidePath);
-    }else{
-      sqlite3_free(zWidePath);
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-      return SQLITE_IOERR_NOMEM;
-    }
+  /* The 3-byte case */
+  p++;
+  a = a<<14;
+  a |= *p;
+  /* a: p0<<14 | p2 (unmasked) */
+  if (!(a&0x80))
+  {
+    /* Values between 16384 and 2097151 */
+    a &= (0x7f<<14)|(0x7f);
+    b &= 0x7f;
+    b = b<<7;
+    *v = a | b;
+    return 3;
   }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    char *zUtf8;
-    char *zMbcsPath = sqlite3MallocZero( nBuf );
-    if( !zMbcsPath ){
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-      return SQLITE_IOERR_NOMEM;
-    }
-    if( osGetTempPathA(nBuf, zMbcsPath)==0 ){
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
-      return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
-                         "winGetTempname2", 0);
-    }
-    zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
-    if( zUtf8 ){
-      sqlite3_snprintf(nBuf-30, zBuf, "%s", zUtf8);
-      sqlite3_free(zUtf8);
+
+  /* A 32-bit varint is used to store size information in btrees.
+  ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
+  ** A 3-byte varint is sufficient, for example, to record the size
+  ** of a 1048569-byte BLOB or string.
+  **
+  ** We only unroll the first 1-, 2-, and 3- byte cases.  The very
+  ** rare larger cases can be handled by the slower 64-bit varint
+  ** routine.
+  */
+#if 1
+  {
+    u64 v64;
+    u8 n;
+
+    p -= 2;
+    n = sqlite3GetVarint(p, &v64);
+    assert( n>3 && n<=9 );
+    if( (v64 & SQLITE_MAX_U32)!=v64 ){
+      *v = 0xffffffff;
     }else{
-      sqlite3_free(zBuf);
-      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
-      return SQLITE_IOERR_NOMEM;
+      *v = (u32)v64;
     }
+    return n;
   }
-#endif /* SQLITE_WIN32_HAS_ANSI */
-#endif /* !SQLITE_OS_WINRT */
 
-  /* Check that the output buffer is large enough for the temporary file 
-  ** name. If it is not, return SQLITE_ERROR.
+#else
+  /* For following code (kept for historical record only) shows an
+  ** unrolling for the 3- and 4-byte varint cases.  This code is
+  ** slightly faster, but it is also larger and much harder to test.
   */
-  nLen = sqlite3Strlen30(zBuf);
+  p++;
+  b = b<<14;
+  b |= *p;
+  /* b: p1<<14 | p3 (unmasked) */
+  if (!(b&0x80))
+  {
+    /* Values between 2097152 and 268435455 */
+    b &= (0x7f<<14)|(0x7f);
+    a &= (0x7f<<14)|(0x7f);
+    a = a<<7;
+    *v = a | b;
+    return 4;
+  }
 
-  if( (nLen + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 18) >= nBuf ){
-    sqlite3_free(zBuf);
-    OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
-    return winLogError(SQLITE_ERROR, 0, "winGetTempname3", 0);
+  p++;
+  a = a<<14;
+  a |= *p;
+  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+  if (!(a&0x80))
+  {
+    /* Values  between 268435456 and 34359738367 */
+    a &= SLOT_4_2_0;
+    b &= SLOT_4_2_0;
+    b = b<<7;
+    *v = a | b;
+    return 5;
   }
 
-  sqlite3_snprintf(nBuf-18-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
+  /* We can only reach this point when reading a corrupt database
+  ** file.  In that case we are not in any hurry.  Use the (relatively
+  ** slow) general-purpose sqlite3GetVarint() routine to extract the
+  ** value. */
+  {
+    u64 v64;
+    u8 n;
 
-  j = sqlite3Strlen30(zBuf);
-  sqlite3_randomness(15, &zBuf[j]);
-  for(i=0; i<15; i++, j++){
-    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+    p -= 4;
+    n = sqlite3GetVarint(p, &v64);
+    assert( n>5 && n<=9 );
+    *v = (u32)v64;
+    return n;
   }
-  zBuf[j] = 0;
-  zBuf[j+1] = 0;
-  *pzBuf = zBuf;
-
-  OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
-  return SQLITE_OK;
+#endif
 }
 
 /*
-** Return TRUE if the named file is really a directory.  Return false if
-** it is something other than a directory, or if there is any kind of memory
-** allocation failure.
+** Return the number of bytes that will be needed to store the given
+** 64-bit integer.
 */
-static int winIsDir(const void *zConverted){
-  DWORD attr;
-  int rc = 0;
-  DWORD lastErrno;
-
-  if( osIsNT() ){
-    int cnt = 0;
-    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
-    memset(&sAttrData, 0, sizeof(sAttrData));
-    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
-                             GetFileExInfoStandard,
-                             &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
-    if( !rc ){
-      return 0; /* Invalid name? */
-    }
-    attr = sAttrData.dwFileAttributes;
-#if SQLITE_OS_WINCE==0
-  }else{
-    attr = osGetFileAttributesA((char*)zConverted);
-#endif
-  }
-  return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
+SQLITE_PRIVATE int sqlite3VarintLen(u64 v){
+  int i = 0;
+  do{
+    i++;
+    v >>= 7;
+  }while( v!=0 && ALWAYS(i<9) );
+  return i;
 }
 
+
 /*
-** Open a file.
+** Read or write a four-byte big-endian integer value.
 */
-static int winOpen(
-  sqlite3_vfs *pVfs,        /* Used to get maximum path name length */
-  const char *zName,        /* Name of the file (UTF-8) */
-  sqlite3_file *id,         /* Write the SQLite file handle here */
-  int flags,                /* Open mode flags */
-  int *pOutFlags            /* Status return flags */
-){
-  HANDLE h;
-  DWORD lastErrno;
-  DWORD dwDesiredAccess;
-  DWORD dwShareMode;
-  DWORD dwCreationDisposition;
-  DWORD dwFlagsAndAttributes = 0;
-#if SQLITE_OS_WINCE
-  int isTemp = 0;
-#endif
-  winFile *pFile = (winFile*)id;
-  void *zConverted;              /* Filename in OS encoding */
-  const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
-  int cnt = 0;
-
-  /* If argument zPath is a NULL pointer, this function is required to open
-  ** a temporary file. Use this buffer to store the file name in.
-  */
-  char *zTmpname = 0; /* For temporary filename, if necessary. */
+SQLITE_PRIVATE u32 sqlite3Get4byte(const u8 *p){
+  return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
+}
+SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
+  p[0] = (u8)(v>>24);
+  p[1] = (u8)(v>>16);
+  p[2] = (u8)(v>>8);
+  p[3] = (u8)v;
+}
 
-  int rc = SQLITE_OK;            /* Function Return Code */
-#if !defined(NDEBUG) || SQLITE_OS_WINCE
-  int eType = flags&0xFFFFFF00;  /* Type of file to open */
-#endif
 
-  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
-  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
-  int isCreate     = (flags & SQLITE_OPEN_CREATE);
-  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
-  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
 
-#ifndef NDEBUG
-  int isOpenJournal = (isCreate && (
-        eType==SQLITE_OPEN_MASTER_JOURNAL 
-     || eType==SQLITE_OPEN_MAIN_JOURNAL 
-     || eType==SQLITE_OPEN_WAL
-  ));
+/*
+** Translate a single byte of Hex into an integer.
+** This routine only works if h really is a valid hexadecimal
+** character:  0..9a..fA..F
+*/
+SQLITE_PRIVATE u8 sqlite3HexToInt(int h){
+  assert( (h>='0' && h<='9') ||  (h>='a' && h<='f') ||  (h>='A' && h<='F') );
+#ifdef SQLITE_ASCII
+  h += 9*(1&(h>>6));
 #endif
-
-  OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
-           zUtf8Name, id, flags, pOutFlags));
-
-  /* Check the following statements are true: 
-  **
-  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
-  **   (b) if CREATE is set, then READWRITE must also be set, and
-  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
-  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
-  */
-  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
-  assert(isCreate==0 || isReadWrite);
-  assert(isExclusive==0 || isCreate);
-  assert(isDelete==0 || isCreate);
-
-  /* The main DB, main journal, WAL file and master journal are never 
-  ** automatically deleted. Nor are they ever temporary files.  */
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
-
-  /* Assert that the upper layer has set one of the "file-type" flags. */
-  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
-       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
-       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
-  );
-
-  assert( pFile!=0 );
-  memset(pFile, 0, sizeof(winFile));
-  pFile->h = INVALID_HANDLE_VALUE;
-
-#if SQLITE_OS_WINRT
-  if( !zUtf8Name && !sqlite3_temp_directory ){
-    sqlite3_log(SQLITE_ERROR,
-        "sqlite3_temp_directory variable should be set for WinRT");
-  }
+#ifdef SQLITE_EBCDIC
+  h += 9*(1&~(h>>4));
 #endif
+  return (u8)(h & 0xf);
+}
 
-  /* If the second argument to this function is NULL, generate a 
-  ** temporary file name to use 
-  */
-  if( !zUtf8Name ){
-    assert( isDelete && !isOpenJournal );
-    rc = winGetTempname(pVfs, &zTmpname);
-    if( rc!=SQLITE_OK ){
-      OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
-      return rc;
+#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
+/*
+** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
+** value.  Return a pointer to its binary value.  Space to hold the
+** binary value has been obtained from malloc and must be freed by
+** the calling routine.
+*/
+SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){
+  char *zBlob;
+  int i;
+
+  zBlob = (char *)sqlite3DbMallocRaw(db, n/2 + 1);
+  n--;
+  if( zBlob ){
+    for(i=0; i<n; i+=2){
+      zBlob[i/2] = (sqlite3HexToInt(z[i])<<4) | sqlite3HexToInt(z[i+1]);
     }
-    zUtf8Name = zTmpname;
+    zBlob[i/2] = 0;
   }
+  return zBlob;
+}
+#endif /* !SQLITE_OMIT_BLOB_LITERAL || SQLITE_HAS_CODEC */
 
-  /* Database filenames are double-zero terminated if they are not
-  ** URIs with parameters.  Hence, they can always be passed into
-  ** sqlite3_uri_parameter().
-  */
-  assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
-       zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
+/*
+** Log an error that is an API call on a connection pointer that should
+** not have been used.  The "type" of connection pointer is given as the
+** argument.  The zType is a word like "NULL" or "closed" or "invalid".
+*/
+static void logBadConnection(const char *zType){
+  sqlite3_log(SQLITE_MISUSE, 
+     "API call with %s database connection pointer",
+     zType
+  );
+}
 
-  /* Convert the filename to the system encoding. */
-  zConverted = winConvertFromUtf8Filename(zUtf8Name);
-  if( zConverted==0 ){
-    sqlite3_free(zTmpname);
-    OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
-    return SQLITE_IOERR_NOMEM;
+/*
+** Check to make sure we have a valid db pointer.  This test is not
+** foolproof but it does provide some measure of protection against
+** misuse of the interface such as passing in db pointers that are
+** NULL or which have been previously closed.  If this routine returns
+** 1 it means that the db pointer is valid and 0 if it should not be
+** dereferenced for any reason.  The calling function should invoke
+** SQLITE_MISUSE immediately.
+**
+** sqlite3SafetyCheckOk() requires that the db pointer be valid for
+** use.  sqlite3SafetyCheckSickOrOk() allows a db pointer that failed to
+** open properly and is not fit for general use but which can be
+** used as an argument to sqlite3_errmsg() or sqlite3_close().
+*/
+SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3 *db){
+  u32 magic;
+  if( db==0 ){
+    logBadConnection("NULL");
+    return 0;
   }
-
-  if( winIsDir(zConverted) ){
-    sqlite3_free(zConverted);
-    sqlite3_free(zTmpname);
-    OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
-    return SQLITE_CANTOPEN_ISDIR;
+  magic = db->magic;
+  if( magic!=SQLITE_MAGIC_OPEN ){
+    if( sqlite3SafetyCheckSickOrOk(db) ){
+      testcase( sqlite3GlobalConfig.xLog!=0 );
+      logBadConnection("unopened");
+    }
+    return 0;
+  }else{
+    return 1;
   }
-
-  if( isReadWrite ){
-    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
+}
+SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
+  u32 magic;
+  magic = db->magic;
+  if( magic!=SQLITE_MAGIC_SICK &&
+      magic!=SQLITE_MAGIC_OPEN &&
+      magic!=SQLITE_MAGIC_BUSY ){
+    testcase( sqlite3GlobalConfig.xLog!=0 );
+    logBadConnection("invalid");
+    return 0;
   }else{
-    dwDesiredAccess = GENERIC_READ;
+    return 1;
   }
+}
 
-  /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
-  ** created. SQLite doesn't use it to indicate "exclusive access" 
-  ** as it is usually understood.
-  */
-  if( isExclusive ){
-    /* Creates a new file, only if it does not already exist. */
-    /* If the file exists, it fails. */
-    dwCreationDisposition = CREATE_NEW;
-  }else if( isCreate ){
-    /* Open existing file, or create if it doesn't exist */
-    dwCreationDisposition = OPEN_ALWAYS;
+/*
+** Attempt to add, substract, or multiply the 64-bit signed value iB against
+** the other 64-bit signed integer at *pA and store the result in *pA.
+** Return 0 on success.  Or if the operation would have resulted in an
+** overflow, leave *pA unchanged and return 1.
+*/
+SQLITE_PRIVATE int sqlite3AddInt64(i64 *pA, i64 iB){
+  i64 iA = *pA;
+  testcase( iA==0 ); testcase( iA==1 );
+  testcase( iB==-1 ); testcase( iB==0 );
+  if( iB>=0 ){
+    testcase( iA>0 && LARGEST_INT64 - iA == iB );
+    testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
+    if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;
+    *pA += iB;
   }else{
-    /* Opens a file, only if it exists. */
-    dwCreationDisposition = OPEN_EXISTING;
+    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
+    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
+    if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;
+    *pA += iB;
   }
-
-  dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
-
-  if( isDelete ){
-#if SQLITE_OS_WINCE
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
-    isTemp = 1;
-#else
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
-                               | FILE_ATTRIBUTE_HIDDEN
-                               | FILE_FLAG_DELETE_ON_CLOSE;
-#endif
+  return 0; 
+}
+SQLITE_PRIVATE int sqlite3SubInt64(i64 *pA, i64 iB){
+  testcase( iB==SMALLEST_INT64+1 );
+  if( iB==SMALLEST_INT64 ){
+    testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
+    if( (*pA)>=0 ) return 1;
+    *pA -= iB;
+    return 0;
   }else{
-    dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
-  }
-  /* Reports from the internet are that performance is always
-  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
-#if SQLITE_OS_WINCE
-  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
-#endif
-
-  if( osIsNT() ){
-#if SQLITE_OS_WINRT
-    CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
-    extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
-    extendedParameters.dwFileAttributes =
-            dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
-    extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
-    extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
-    extendedParameters.lpSecurityAttributes = NULL;
-    extendedParameters.hTemplateFile = NULL;
-    while( (h = osCreateFile2((LPCWSTR)zConverted,
-                              dwDesiredAccess,
-                              dwShareMode,
-                              dwCreationDisposition,
-                              &extendedParameters))==INVALID_HANDLE_VALUE &&
-                              winRetryIoerr(&cnt, &lastErrno) ){
-               /* Noop */
-    }
-#else
-    while( (h = osCreateFileW((LPCWSTR)zConverted,
-                              dwDesiredAccess,
-                              dwShareMode, NULL,
-                              dwCreationDisposition,
-                              dwFlagsAndAttributes,
-                              NULL))==INVALID_HANDLE_VALUE &&
-                              winRetryIoerr(&cnt, &lastErrno) ){
-               /* Noop */
-    }
-#endif
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    while( (h = osCreateFileA((LPCSTR)zConverted,
-                              dwDesiredAccess,
-                              dwShareMode, NULL,
-                              dwCreationDisposition,
-                              dwFlagsAndAttributes,
-                              NULL))==INVALID_HANDLE_VALUE &&
-                              winRetryIoerr(&cnt, &lastErrno) ){
-               /* Noop */
-    }
-  }
-#endif
-  winLogIoerr(cnt);
-
-  OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
-           dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
-
-  if( h==INVALID_HANDLE_VALUE ){
-    pFile->lastErrno = lastErrno;
-    winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
-    sqlite3_free(zConverted);
-    sqlite3_free(zTmpname);
-    if( isReadWrite && !isExclusive ){
-      return winOpen(pVfs, zName, id, 
-         ((flags|SQLITE_OPEN_READONLY) &
-                     ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
-         pOutFlags);
-    }else{
-      return SQLITE_CANTOPEN_BKPT;
-    }
+    return sqlite3AddInt64(pA, -iB);
   }
+}
+#define TWOPOWER32 (((i64)1)<<32)
+#define TWOPOWER31 (((i64)1)<<31)
+SQLITE_PRIVATE int sqlite3MulInt64(i64 *pA, i64 iB){
+  i64 iA = *pA;
+  i64 iA1, iA0, iB1, iB0, r;
 
-  if( pOutFlags ){
-    if( isReadWrite ){
-      *pOutFlags = SQLITE_OPEN_READWRITE;
-    }else{
-      *pOutFlags = SQLITE_OPEN_READONLY;
-    }
-  }
+  iA1 = iA/TWOPOWER32;
+  iA0 = iA % TWOPOWER32;
+  iB1 = iB/TWOPOWER32;
+  iB0 = iB % TWOPOWER32;
+  if( iA1*iB1 != 0 ) return 1;
+  assert( iA1*iB0==0 || iA0*iB1==0 );
+  r = iA1*iB0 + iA0*iB1;
+  testcase( r==(-TWOPOWER31)-1 );
+  testcase( r==(-TWOPOWER31) );
+  testcase( r==TWOPOWER31 );
+  testcase( r==TWOPOWER31-1 );
+  if( r<(-TWOPOWER31) || r>=TWOPOWER31 ) return 1;
+  r *= TWOPOWER32;
+  if( sqlite3AddInt64(&r, iA0*iB0) ) return 1;
+  *pA = r;
+  return 0;
+}
 
-  OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
-           "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
-           *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
+/*
+** Compute the absolute value of a 32-bit signed integer, of possible.  Or 
+** if the integer has a value of -2147483648, return +2147483647
+*/
+SQLITE_PRIVATE int sqlite3AbsInt32(int x){
+  if( x>=0 ) return x;
+  if( x==(int)0x80000000 ) return 0x7fffffff;
+  return -x;
+}
 
-#if SQLITE_OS_WINCE
-  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
-       && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
-  ){
-    osCloseHandle(h);
-    sqlite3_free(zConverted);
-    sqlite3_free(zTmpname);
-    OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
-    return rc;
-  }
-  if( isTemp ){
-    pFile->zDeleteOnClose = zConverted;
-  }else
+#ifdef SQLITE_ENABLE_8_3_NAMES
+/*
+** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database
+** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
+** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
+** three characters, then shorten the suffix on z[] to be the last three
+** characters of the original suffix.
+**
+** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always
+** do the suffix shortening regardless of URI parameter.
+**
+** Examples:
+**
+**     test.db-journal    =>   test.nal
+**     test.db-wal        =>   test.wal
+**     test.db-shm        =>   test.shm
+**     test.db-mj7f3319fa =>   test.9fa
+*/
+SQLITE_PRIVATE void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
+#if SQLITE_ENABLE_8_3_NAMES<2
+  if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) )
 #endif
   {
-    sqlite3_free(zConverted);
+    int i, sz;
+    sz = sqlite3Strlen30(z);
+    for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
+    if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
   }
+}
+#endif
 
-  sqlite3_free(zTmpname);
-  pFile->pMethod = &winIoMethod;
-  pFile->pVfs = pVfs;
-  pFile->h = h;
-  if( isReadonly ){
-    pFile->ctrlFlags |= WINFILE_RDONLY;
+/* 
+** Find (an approximate) sum of two LogEst values.  This computation is
+** not a simple "+" operator because LogEst is stored as a logarithmic
+** value.
+** 
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
+  static const unsigned char x[] = {
+     10, 10,                         /* 0,1 */
+      9, 9,                          /* 2,3 */
+      8, 8,                          /* 4,5 */
+      7, 7, 7,                       /* 6,7,8 */
+      6, 6, 6,                       /* 9,10,11 */
+      5, 5, 5,                       /* 12-14 */
+      4, 4, 4, 4,                    /* 15-18 */
+      3, 3, 3, 3, 3, 3,              /* 19-24 */
+      2, 2, 2, 2, 2, 2, 2,           /* 25-31 */
+  };
+  if( a>=b ){
+    if( a>b+49 ) return a;
+    if( a>b+31 ) return a+1;
+    return a+x[a-b];
+  }else{
+    if( b>a+49 ) return b;
+    if( b>a+31 ) return b+1;
+    return b+x[b-a];
   }
-  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
-    pFile->ctrlFlags |= WINFILE_PSOW;
+}
+
+/*
+** Convert an integer into a LogEst.  In other words, compute a
+** good approximatation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEst(u64 x){
+  static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
+  LogEst y = 40;
+  if( x<8 ){
+    if( x<2 ) return 0;
+    while( x<8 ){  y -= 10; x <<= 1; }
+  }else{
+    while( x>255 ){ y += 40; x >>= 4; }
+    while( x>15 ){  y += 10; x >>= 1; }
   }
-  pFile->lastErrno = NO_ERROR;
-  pFile->zPath = zName;
-#if SQLITE_MAX_MMAP_SIZE>0
-  pFile->hMap = NULL;
-  pFile->pMapRegion = 0;
-  pFile->mmapSize = 0;
-  pFile->mmapSizeActual = 0;
-  pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
-#endif
+  return a[x&7] + y - 10;
+}
 
-  OpenCounter(+1);
-  return rc;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Convert a double into a LogEst
+** In other words, compute an approximation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double x){
+  u64 a;
+  LogEst e;
+  assert( sizeof(x)==8 && sizeof(a)==8 );
+  if( x<=1 ) return 0;
+  if( x<=2000000000 ) return sqlite3LogEst((u64)x);
+  memcpy(&a, &x, 8);
+  e = (a>>52) - 1022;
+  return e*10;
 }
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
 
 /*
-** Delete the named file.
-**
-** Note that Windows does not allow a file to be deleted if some other
-** process has it open.  Sometimes a virus scanner or indexing program
-** will open a journal file shortly after it is created in order to do
-** whatever it does.  While this other process is holding the
-** file open, we will be unable to delete it.  To work around this
-** problem, we delay 100 milliseconds and try to delete again.  Up
-** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
-** up and returning an error.
+** Convert a LogEst into an integer.
 */
-static int winDelete(
-  sqlite3_vfs *pVfs,          /* Not used on win32 */
-  const char *zFilename,      /* Name of file to delete */
-  int syncDir                 /* Not used on win32 */
-){
-  int cnt = 0;
-  int rc;
-  DWORD attr;
-  DWORD lastErrno;
-  void *zConverted;
-  UNUSED_PARAMETER(pVfs);
-  UNUSED_PARAMETER(syncDir);
+SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst x){
+  u64 n;
+  if( x<10 ) return 1;
+  n = x%10;
+  x /= 10;
+  if( n>=5 ) n -= 2;
+  else if( n>=1 ) n -= 1;
+  if( x>=3 ) return (n+8)<<(x-3);
+  return (n+8)>>(3-x);
+}
 
-  SimulateIOError(return SQLITE_IOERR_DELETE);
-  OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
+/************** End of util.c ************************************************/
+/************** Begin file hash.c ********************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of generic hash-tables
+** used in SQLite.
+*/
+/* #include <assert.h> */
 
-  zConverted = winConvertFromUtf8Filename(zFilename);
-  if( zConverted==0 ){
-    OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
-    return SQLITE_IOERR_NOMEM;
-  }
-  if( osIsNT() ){
-    do {
-#if SQLITE_OS_WINRT
-      WIN32_FILE_ATTRIBUTE_DATA sAttrData;
-      memset(&sAttrData, 0, sizeof(sAttrData));
-      if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
-                                  &sAttrData) ){
-        attr = sAttrData.dwFileAttributes;
-      }else{
-        lastErrno = osGetLastError();
-        if( lastErrno==ERROR_FILE_NOT_FOUND
-         || lastErrno==ERROR_PATH_NOT_FOUND ){
-          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
-        }else{
-          rc = SQLITE_ERROR;
-        }
-        break;
-      }
-#else
-      attr = osGetFileAttributesW(zConverted);
-#endif
-      if ( attr==INVALID_FILE_ATTRIBUTES ){
-        lastErrno = osGetLastError();
-        if( lastErrno==ERROR_FILE_NOT_FOUND
-         || lastErrno==ERROR_PATH_NOT_FOUND ){
-          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
-        }else{
-          rc = SQLITE_ERROR;
-        }
-        break;
-      }
-      if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
-        rc = SQLITE_ERROR; /* Files only. */
-        break;
-      }
-      if ( osDeleteFileW(zConverted) ){
-        rc = SQLITE_OK; /* Deleted OK. */
-        break;
-      }
-      if ( !winRetryIoerr(&cnt, &lastErrno) ){
-        rc = SQLITE_ERROR; /* No more retries. */
-        break;
-      }
-    } while(1);
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    do {
-      attr = osGetFileAttributesA(zConverted);
-      if ( attr==INVALID_FILE_ATTRIBUTES ){
-        lastErrno = osGetLastError();
-        if( lastErrno==ERROR_FILE_NOT_FOUND
-         || lastErrno==ERROR_PATH_NOT_FOUND ){
-          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
-        }else{
-          rc = SQLITE_ERROR;
-        }
-        break;
-      }
-      if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
-        rc = SQLITE_ERROR; /* Files only. */
-        break;
-      }
-      if ( osDeleteFileA(zConverted) ){
-        rc = SQLITE_OK; /* Deleted OK. */
-        break;
-      }
-      if ( !winRetryIoerr(&cnt, &lastErrno) ){
-        rc = SQLITE_ERROR; /* No more retries. */
-        break;
-      }
-    } while(1);
-  }
-#endif
-  if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
-    rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
-  }else{
-    winLogIoerr(cnt);
-  }
-  sqlite3_free(zConverted);
-  OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
-  return rc;
+/* Turn bulk memory into a hash table object by initializing the
+** fields of the Hash structure.
+**
+** "pNew" is a pointer to the hash table that is to be initialized.
+*/
+SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew){
+  assert( pNew!=0 );
+  pNew->first = 0;
+  pNew->count = 0;
+  pNew->htsize = 0;
+  pNew->ht = 0;
 }
 
-/*
-** Check the existence and status of a file.
+/* Remove all entries from a hash table.  Reclaim all memory.
+** Call this routine to delete a hash table or to reset a hash table
+** to the empty state.
 */
-static int winAccess(
-  sqlite3_vfs *pVfs,         /* Not used on win32 */
-  const char *zFilename,     /* Name of file to check */
-  int flags,                 /* Type of test to make on this file */
-  int *pResOut               /* OUT: Result */
-){
-  DWORD attr;
-  int rc = 0;
-  DWORD lastErrno;
-  void *zConverted;
-  UNUSED_PARAMETER(pVfs);
+SQLITE_PRIVATE void sqlite3HashClear(Hash *pH){
+  HashElem *elem;         /* For looping over all elements of the table */
 
-  SimulateIOError( return SQLITE_IOERR_ACCESS; );
-  OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
-           zFilename, flags, pResOut));
-
-  zConverted = winConvertFromUtf8Filename(zFilename);
-  if( zConverted==0 ){
-    OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
-    return SQLITE_IOERR_NOMEM;
-  }
-  if( osIsNT() ){
-    int cnt = 0;
-    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
-    memset(&sAttrData, 0, sizeof(sAttrData));
-    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
-                             GetFileExInfoStandard, 
-                             &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
-    if( rc ){
-      /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
-      ** as if it does not exist.
-      */
-      if(    flags==SQLITE_ACCESS_EXISTS
-          && sAttrData.nFileSizeHigh==0 
-          && sAttrData.nFileSizeLow==0 ){
-        attr = INVALID_FILE_ATTRIBUTES;
-      }else{
-        attr = sAttrData.dwFileAttributes;
-      }
-    }else{
-      winLogIoerr(cnt);
-      if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
-        sqlite3_free(zConverted);
-        return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
-                           zFilename);
-      }else{
-        attr = INVALID_FILE_ATTRIBUTES;
-      }
-    }
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    attr = osGetFileAttributesA((char*)zConverted);
-  }
-#endif
-  sqlite3_free(zConverted);
-  switch( flags ){
-    case SQLITE_ACCESS_READ:
-    case SQLITE_ACCESS_EXISTS:
-      rc = attr!=INVALID_FILE_ATTRIBUTES;
-      break;
-    case SQLITE_ACCESS_READWRITE:
-      rc = attr!=INVALID_FILE_ATTRIBUTES &&
-             (attr & FILE_ATTRIBUTE_READONLY)==0;
-      break;
-    default:
-      assert(!"Invalid flags argument");
+  assert( pH!=0 );
+  elem = pH->first;
+  pH->first = 0;
+  sqlite3_free(pH->ht);
+  pH->ht = 0;
+  pH->htsize = 0;
+  while( elem ){
+    HashElem *next_elem = elem->next;
+    sqlite3_free(elem);
+    elem = next_elem;
   }
-  *pResOut = rc;
-  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
-           zFilename, pResOut, *pResOut));
-  return SQLITE_OK;
+  pH->count = 0;
 }
 
 /*
-** Returns non-zero if the specified path name starts with a drive letter
-** followed by a colon character.
+** The hashing function.
 */
-static BOOL winIsDriveLetterAndColon(
-  const char *zPathname
-){
-  return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
+static unsigned int strHash(const char *z, int nKey){
+  int h = 0;
+  assert( nKey>=0 );
+  while( nKey > 0  ){
+    h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
+    nKey--;
+  }
+  return h;
 }
 
-/*
-** Returns non-zero if the specified path name should be used verbatim.  If
-** non-zero is returned from this function, the calling function must simply
-** use the provided path name verbatim -OR- resolve it into a full path name
-** using the GetFullPathName Win32 API function (if available).
+
+/* Link pNew element into the hash table pH.  If pEntry!=0 then also
+** insert pNew into the pEntry hash bucket.
 */
-static BOOL winIsVerbatimPathname(
-  const char *zPathname
+static void insertElement(
+  Hash *pH,              /* The complete hash table */
+  struct _ht *pEntry,    /* The entry into which pNew is inserted */
+  HashElem *pNew         /* The element to be inserted */
 ){
-  /*
-  ** If the path name starts with a forward slash or a backslash, it is either
-  ** a legal UNC name, a volume relative path, or an absolute path name in the
-  ** "Unix" format on Windows.  There is no easy way to differentiate between
-  ** the final two cases; therefore, we return the safer return value of TRUE
-  ** so that callers of this function will simply use it verbatim.
-  */
-  if ( winIsDirSep(zPathname[0]) ){
-    return TRUE;
+  HashElem *pHead;       /* First element already in pEntry */
+  if( pEntry ){
+    pHead = pEntry->count ? pEntry->chain : 0;
+    pEntry->count++;
+    pEntry->chain = pNew;
+  }else{
+    pHead = 0;
   }
-
-  /*
-  ** If the path name starts with a letter and a colon it is either a volume
-  ** relative path or an absolute path.  Callers of this function must not
-  ** attempt to treat it as a relative path name (i.e. they should simply use
-  ** it verbatim).
-  */
-  if ( winIsDriveLetterAndColon(zPathname) ){
-    return TRUE;
+  if( pHead ){
+    pNew->next = pHead;
+    pNew->prev = pHead->prev;
+    if( pHead->prev ){ pHead->prev->next = pNew; }
+    else             { pH->first = pNew; }
+    pHead->prev = pNew;
+  }else{
+    pNew->next = pH->first;
+    if( pH->first ){ pH->first->prev = pNew; }
+    pNew->prev = 0;
+    pH->first = pNew;
   }
-
-  /*
-  ** If we get to this point, the path name should almost certainly be a purely
-  ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
-  */
-  return FALSE;
 }
 
-/*
-** Turn a relative pathname into a full pathname.  Write the full
-** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
-** bytes in size.
+
+/* Resize the hash table so that it cantains "new_size" buckets.
+**
+** The hash table might fail to resize if sqlite3_malloc() fails or
+** if the new size is the same as the prior size.
+** Return TRUE if the resize occurs and false if not.
 */
-static int winFullPathname(
-  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
-  const char *zRelative,        /* Possibly relative input path */
-  int nFull,                    /* Size of output buffer in bytes */
-  char *zFull                   /* Output buffer */
-){
-  
-#if defined(__CYGWIN__)
-  SimulateIOError( return SQLITE_ERROR );
-  UNUSED_PARAMETER(nFull);
-  assert( nFull>=pVfs->mxPathname );
-  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
-    /*
-    ** NOTE: We are dealing with a relative path name and the data
-    **       directory has been set.  Therefore, use it as the basis
-    **       for converting the relative path name to an absolute
-    **       one by prepending the data directory and a slash.
-    */
-    char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
-    if( !zOut ){
-      return SQLITE_IOERR_NOMEM;
-    }
-    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A|CCP_RELATIVE, zRelative, zOut,
-                         pVfs->mxPathname+1)<0 ){
-      sqlite3_free(zOut);
-      return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
-                         "winFullPathname1", zRelative);
-    }
-    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
-                     sqlite3_data_directory, winGetDirDep(), zOut);
-    sqlite3_free(zOut);
-  }else{
-    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A, zRelative, zFull, nFull)<0 ){
-      return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
-                         "winFullPathname2", zRelative);
-    }
-  }
-  return SQLITE_OK;
-#endif
+static int rehash(Hash *pH, unsigned int new_size){
+  struct _ht *new_ht;            /* The new hash table */
+  HashElem *elem, *next_elem;    /* For looping over existing elements */
 
-#if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
-  SimulateIOError( return SQLITE_ERROR );
-  /* WinCE has no concept of a relative pathname, or so I am told. */
-  /* WinRT has no way to convert a relative path to an absolute one. */
-  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
-    /*
-    ** NOTE: We are dealing with a relative path name and the data
-    **       directory has been set.  Therefore, use it as the basis
-    **       for converting the relative path name to an absolute
-    **       one by prepending the data directory and a backslash.
-    */
-    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
-                     sqlite3_data_directory, winGetDirDep(), zRelative);
-  }else{
-    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
+#if SQLITE_MALLOC_SOFT_LIMIT>0
+  if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
+    new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
   }
-  return SQLITE_OK;
+  if( new_size==pH->htsize ) return 0;
 #endif
 
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
-  DWORD nByte;
-  void *zConverted;
-  char *zOut;
-
-  /* If this path name begins with "/X:", where "X" is any alphabetic
-  ** character, discard the initial "/" from the pathname.
+  /* The inability to allocates space for a larger hash table is
+  ** a performance hit but it is not a fatal error.  So mark the
+  ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of 
+  ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
+  ** only zeroes the requested number of bytes whereas this module will
+  ** use the actual amount of space allocated for the hash table (which
+  ** may be larger than the requested amount).
   */
-  if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
-    zRelative++;
-  }
+  sqlite3BeginBenignMalloc();
+  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
+  sqlite3EndBenignMalloc();
 
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. This function could fail if, for example, the
-  ** current working directory has been unlinked.
-  */
-  SimulateIOError( return SQLITE_ERROR );
-  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
-    /*
-    ** NOTE: We are dealing with a relative path name and the data
-    **       directory has been set.  Therefore, use it as the basis
-    **       for converting the relative path name to an absolute
-    **       one by prepending the data directory and a backslash.
-    */
-    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
-                     sqlite3_data_directory, winGetDirDep(), zRelative);
-    return SQLITE_OK;
-  }
-  zConverted = winConvertFromUtf8Filename(zRelative);
-  if( zConverted==0 ){
-    return SQLITE_IOERR_NOMEM;
-  }
-  if( osIsNT() ){
-    LPWSTR zTemp;
-    nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
-    if( nByte==0 ){
-      sqlite3_free(zConverted);
-      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
-                         "winFullPathname1", zRelative);
-    }
-    nByte += 3;
-    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
-    if( zTemp==0 ){
-      sqlite3_free(zConverted);
-      return SQLITE_IOERR_NOMEM;
-    }
-    nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
-    if( nByte==0 ){
-      sqlite3_free(zConverted);
-      sqlite3_free(zTemp);
-      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
-                         "winFullPathname2", zRelative);
-    }
-    sqlite3_free(zConverted);
-    zOut = winUnicodeToUtf8(zTemp);
-    sqlite3_free(zTemp);
-  }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    char *zTemp;
-    nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
-    if( nByte==0 ){
-      sqlite3_free(zConverted);
-      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
-                         "winFullPathname3", zRelative);
-    }
-    nByte += 3;
-    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
-    if( zTemp==0 ){
-      sqlite3_free(zConverted);
-      return SQLITE_IOERR_NOMEM;
-    }
-    nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
-    if( nByte==0 ){
-      sqlite3_free(zConverted);
-      sqlite3_free(zTemp);
-      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
-                         "winFullPathname4", zRelative);
-    }
-    sqlite3_free(zConverted);
-    zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
-    sqlite3_free(zTemp);
-  }
-#endif
-  if( zOut ){
-    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
-    sqlite3_free(zOut);
-    return SQLITE_OK;
-  }else{
-    return SQLITE_IOERR_NOMEM;
+  if( new_ht==0 ) return 0;
+  sqlite3_free(pH->ht);
+  pH->ht = new_ht;
+  pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
+  memset(new_ht, 0, new_size*sizeof(struct _ht));
+  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
+    unsigned int h = strHash(elem->pKey, elem->nKey) % new_size;
+    next_elem = elem->next;
+    insertElement(pH, &new_ht[h], elem);
   }
-#endif
+  return 1;
 }
 
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
-/*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
-*/
-/*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
+/* This function (for internal use only) locates an element in an
+** hash table that matches the given key.  The hash for this key has
+** already been computed and is passed as the 4th parameter.
 */
-static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
-  HANDLE h;
-  void *zConverted = winConvertFromUtf8Filename(zFilename);
-  UNUSED_PARAMETER(pVfs);
-  if( zConverted==0 ){
-    return 0;
-  }
-  if( osIsNT() ){
-#if SQLITE_OS_WINRT
-    h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
-#else
-    h = osLoadLibraryW((LPCWSTR)zConverted);
-#endif
+static HashElem *findElementGivenHash(
+  const Hash *pH,     /* The pH to be searched */
+  const char *pKey,   /* The key we are searching for */
+  int nKey,           /* Bytes in key (not counting zero terminator) */
+  unsigned int h      /* The hash for this key. */
+){
+  HashElem *elem;                /* Used to loop thru the element list */
+  int count;                     /* Number of elements left to test */
+
+  if( pH->ht ){
+    struct _ht *pEntry = &pH->ht[h];
+    elem = pEntry->chain;
+    count = pEntry->count;
+  }else{
+    elem = pH->first;
+    count = pH->count;
   }
-#ifdef SQLITE_WIN32_HAS_ANSI
-  else{
-    h = osLoadLibraryA((char*)zConverted);
+  while( count-- && ALWAYS(elem) ){
+    if( elem->nKey==nKey && sqlite3StrNICmp(elem->pKey,pKey,nKey)==0 ){ 
+      return elem;
+    }
+    elem = elem->next;
   }
-#endif
-  sqlite3_free(zConverted);
-  return (void*)h;
-}
-static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
-  UNUSED_PARAMETER(pVfs);
-  winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
-}
-static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
-  UNUSED_PARAMETER(pVfs);
-  return (void(*)(void))osGetProcAddressA((HANDLE)pH, zSym);
-}
-static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
-  UNUSED_PARAMETER(pVfs);
-  osFreeLibrary((HANDLE)pHandle);
+  return 0;
 }
-#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
-  #define winDlOpen  0
-  #define winDlError 0
-  #define winDlSym   0
-  #define winDlClose 0
-#endif
 
-
-/*
-** Write up to nBuf bytes of randomness into zBuf.
+/* Remove a single entry from the hash table given a pointer to that
+** element and a hash on the element's key.
 */
-static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  int n = 0;
-  UNUSED_PARAMETER(pVfs);
-#if defined(SQLITE_TEST)
-  n = nBuf;
-  memset(zBuf, 0, nBuf);
-#else
-  if( sizeof(SYSTEMTIME)<=nBuf-n ){
-    SYSTEMTIME x;
-    osGetSystemTime(&x);
-    memcpy(&zBuf[n], &x, sizeof(x));
-    n += sizeof(x);
-  }
-  if( sizeof(DWORD)<=nBuf-n ){
-    DWORD pid = osGetCurrentProcessId();
-    memcpy(&zBuf[n], &pid, sizeof(pid));
-    n += sizeof(pid);
-  }
-#if SQLITE_OS_WINRT
-  if( sizeof(ULONGLONG)<=nBuf-n ){
-    ULONGLONG cnt = osGetTickCount64();
-    memcpy(&zBuf[n], &cnt, sizeof(cnt));
-    n += sizeof(cnt);
-  }
-#else
-  if( sizeof(DWORD)<=nBuf-n ){
-    DWORD cnt = osGetTickCount();
-    memcpy(&zBuf[n], &cnt, sizeof(cnt));
-    n += sizeof(cnt);
+static void removeElementGivenHash(
+  Hash *pH,         /* The pH containing "elem" */
+  HashElem* elem,   /* The element to be removed from the pH */
+  unsigned int h    /* Hash value for the element */
+){
+  struct _ht *pEntry;
+  if( elem->prev ){
+    elem->prev->next = elem->next; 
+  }else{
+    pH->first = elem->next;
   }
-#endif
-  if( sizeof(LARGE_INTEGER)<=nBuf-n ){
-    LARGE_INTEGER i;
-    osQueryPerformanceCounter(&i);
-    memcpy(&zBuf[n], &i, sizeof(i));
-    n += sizeof(i);
+  if( elem->next ){
+    elem->next->prev = elem->prev;
   }
-#endif
-  return n;
-}
-
-
-/*
-** Sleep for a little while.  Return the amount of time slept.
-*/
-static int winSleep(sqlite3_vfs *pVfs, int microsec){
-  sqlite3_win32_sleep((microsec+999)/1000);
-  UNUSED_PARAMETER(pVfs);
-  return ((microsec+999)/1000)*1000;
-}
-
-/*
-** The following variable, if set to a non-zero value, is interpreted as
-** the number of seconds since 1970 and is used to set the result of
-** sqlite3OsCurrentTime() during testing.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
-#endif
-
-/*
-** Find the current time (in Universal Coordinated Time).  Write into *piNow
-** the current time and date as a Julian Day number times 86_400_000.  In
-** other words, write into *piNow the number of milliseconds since the Julian
-** epoch of noon in Greenwich on November 24, 4714 B.C according to the
-** proleptic Gregorian calendar.
-**
-** On success, return SQLITE_OK.  Return SQLITE_ERROR if the time and date 
-** cannot be found.
-*/
-static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
-  /* FILETIME structure is a 64-bit value representing the number of 
-     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
-  */
-  FILETIME ft;
-  static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
-#ifdef SQLITE_TEST
-  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
-#endif
-  /* 2^32 - to avoid use of LL and warnings in gcc */
-  static const sqlite3_int64 max32BitValue = 
-      (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
-      (sqlite3_int64)294967296;
-
-#if SQLITE_OS_WINCE
-  SYSTEMTIME time;
-  osGetSystemTime(&time);
-  /* if SystemTimeToFileTime() fails, it returns zero. */
-  if (!osSystemTimeToFileTime(&time,&ft)){
-    return SQLITE_ERROR;
+  if( pH->ht ){
+    pEntry = &pH->ht[h];
+    if( pEntry->chain==elem ){
+      pEntry->chain = elem->next;
+    }
+    pEntry->count--;
+    assert( pEntry->count>=0 );
   }
-#else
-  osGetSystemTimeAsFileTime( &ft );
-#endif
-
-  *piNow = winFiletimeEpoch +
-            ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) + 
-               (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
-
-#ifdef SQLITE_TEST
-  if( sqlite3_current_time ){
-    *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
+  sqlite3_free( elem );
+  pH->count--;
+  if( pH->count==0 ){
+    assert( pH->first==0 );
+    assert( pH->count==0 );
+    sqlite3HashClear(pH);
   }
-#endif
-  UNUSED_PARAMETER(pVfs);
-  return SQLITE_OK;
 }
 
-/*
-** Find the current time (in Universal Coordinated Time).  Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0.  Return 1 if the time and date cannot be found.
+/* Attempt to locate an element of the hash table pH with a key
+** that matches pKey,nKey.  Return the data for this element if it is
+** found, or NULL if there is no match.
 */
-static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
-  int rc;
-  sqlite3_int64 i;
-  rc = winCurrentTimeInt64(pVfs, &i);
-  if( !rc ){
-    *prNow = i/86400000.0;
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const char *pKey, int nKey){
+  HashElem *elem;    /* The element that matches key */
+  unsigned int h;    /* A hash on key */
+
+  assert( pH!=0 );
+  assert( pKey!=0 );
+  assert( nKey>=0 );
+  if( pH->ht ){
+    h = strHash(pKey, nKey) % pH->htsize;
+  }else{
+    h = 0;
   }
-  return rc;
+  elem = findElementGivenHash(pH, pKey, nKey, h);
+  return elem ? elem->data : 0;
 }
 
-/*
-** The idea is that this function works like a combination of
-** GetLastError() and FormatMessage() on Windows (or errno and
-** strerror_r() on Unix). After an error is returned by an OS
-** function, SQLite calls this function with zBuf pointing to
-** a buffer of nBuf bytes. The OS layer should populate the
-** buffer with a nul-terminated UTF-8 encoded error message
-** describing the last IO error to have occurred within the calling
-** thread.
-**
-** If the error message is too large for the supplied buffer,
-** it should be truncated. The return value of xGetLastError
-** is zero if the error message fits in the buffer, or non-zero
-** otherwise (if the message was truncated). If non-zero is returned,
-** then it is not necessary to include the nul-terminator character
-** in the output buffer.
+/* Insert an element into the hash table pH.  The key is pKey,nKey
+** and the data is "data".
 **
-** Not supplying an error message will have no adverse effect
-** on SQLite. It is fine to have an implementation that never
-** returns an error message:
+** If no element exists with a matching key, then a new
+** element is created and NULL is returned.
 **
-**   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-**     assert(zBuf[0]=='\0');
-**     return 0;
-**   }
+** If another element already exists with the same key, then the
+** new data replaces the old data and the old data is returned.
+** The key is not copied in this instance.  If a malloc fails, then
+** the new data is returned and the hash table is unchanged.
 **
-** However if an error message is supplied, it will be incorporated
-** by sqlite into the error message available to the user using
-** sqlite3_errmsg(), possibly making IO errors easier to debug.
+** If the "data" parameter to this function is NULL, then the
+** element corresponding to "key" is removed from the hash table.
 */
-static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  UNUSED_PARAMETER(pVfs);
-  return winGetLastErrorMsg(osGetLastError(), nBuf, zBuf);
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){
+  unsigned int h;       /* the hash of the key modulo hash table size */
+  HashElem *elem;       /* Used to loop thru the element list */
+  HashElem *new_elem;   /* New element added to the pH */
+
+  assert( pH!=0 );
+  assert( pKey!=0 );
+  assert( nKey>=0 );
+  if( pH->htsize ){
+    h = strHash(pKey, nKey) % pH->htsize;
+  }else{
+    h = 0;
+  }
+  elem = findElementGivenHash(pH,pKey,nKey,h);
+  if( elem ){
+    void *old_data = elem->data;
+    if( data==0 ){
+      removeElementGivenHash(pH,elem,h);
+    }else{
+      elem->data = data;
+      elem->pKey = pKey;
+      assert(nKey==elem->nKey);
+    }
+    return old_data;
+  }
+  if( data==0 ) return 0;
+  new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
+  if( new_elem==0 ) return data;
+  new_elem->pKey = pKey;
+  new_elem->nKey = nKey;
+  new_elem->data = data;
+  pH->count++;
+  if( pH->count>=10 && pH->count > 2*pH->htsize ){
+    if( rehash(pH, pH->count*2) ){
+      assert( pH->htsize>0 );
+      h = strHash(pKey, nKey) % pH->htsize;
+    }
+  }
+  if( pH->ht ){
+    insertElement(pH, &pH->ht[h], new_elem);
+  }else{
+    insertElement(pH, 0, new_elem);
+  }
+  return 0;
 }
 
-/*
-** Initialize and deinitialize the operating system interface.
-*/
-SQLITE_API int sqlite3_os_init(void){
-  static sqlite3_vfs winVfs = {
-    3,                   /* iVersion */
-    sizeof(winFile),     /* szOsFile */
-    SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
-    0,                   /* pNext */
-    "win32",             /* zName */
-    0,                   /* pAppData */
-    winOpen,             /* xOpen */
-    winDelete,           /* xDelete */
-    winAccess,           /* xAccess */
-    winFullPathname,     /* xFullPathname */
-    winDlOpen,           /* xDlOpen */
-    winDlError,          /* xDlError */
-    winDlSym,            /* xDlSym */
-    winDlClose,          /* xDlClose */
-    winRandomness,       /* xRandomness */
-    winSleep,            /* xSleep */
-    winCurrentTime,      /* xCurrentTime */
-    winGetLastError,     /* xGetLastError */
-    winCurrentTimeInt64, /* xCurrentTimeInt64 */
-    winSetSystemCall,    /* xSetSystemCall */
-    winGetSystemCall,    /* xGetSystemCall */
-    winNextSystemCall,   /* xNextSystemCall */
-  };
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  static sqlite3_vfs winLongPathVfs = {
-    3,                   /* iVersion */
-    sizeof(winFile),     /* szOsFile */
-    SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
-    0,                   /* pNext */
-    "win32-longpath",    /* zName */
-    0,                   /* pAppData */
-    winOpen,             /* xOpen */
-    winDelete,           /* xDelete */
-    winAccess,           /* xAccess */
-    winFullPathname,     /* xFullPathname */
-    winDlOpen,           /* xDlOpen */
-    winDlError,          /* xDlError */
-    winDlSym,            /* xDlSym */
-    winDlClose,          /* xDlClose */
-    winRandomness,       /* xRandomness */
-    winSleep,            /* xSleep */
-    winCurrentTime,      /* xCurrentTime */
-    winGetLastError,     /* xGetLastError */
-    winCurrentTimeInt64, /* xCurrentTimeInt64 */
-    winSetSystemCall,    /* xSetSystemCall */
-    winGetSystemCall,    /* xGetSystemCall */
-    winNextSystemCall,   /* xNextSystemCall */
+/************** End of hash.c ************************************************/
+/************** Begin file opcodes.c *****************************************/
+/* Automatically generated.  Do not edit */
+/* See the mkopcodec.awk script for details. */
+#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
+ static const char *const azName[] = { "?",
+     /*   1 */ "Function",
+     /*   2 */ "Savepoint",
+     /*   3 */ "AutoCommit",
+     /*   4 */ "Transaction",
+     /*   5 */ "SorterNext",
+     /*   6 */ "Prev",
+     /*   7 */ "Next",
+     /*   8 */ "AggStep",
+     /*   9 */ "Checkpoint",
+     /*  10 */ "JournalMode",
+     /*  11 */ "Vacuum",
+     /*  12 */ "VFilter",
+     /*  13 */ "VUpdate",
+     /*  14 */ "Goto",
+     /*  15 */ "Gosub",
+     /*  16 */ "Return",
+     /*  17 */ "Yield",
+     /*  18 */ "HaltIfNull",
+     /*  19 */ "Not",
+     /*  20 */ "Halt",
+     /*  21 */ "Integer",
+     /*  22 */ "Int64",
+     /*  23 */ "String",
+     /*  24 */ "Null",
+     /*  25 */ "Blob",
+     /*  26 */ "Variable",
+     /*  27 */ "Move",
+     /*  28 */ "Copy",
+     /*  29 */ "SCopy",
+     /*  30 */ "ResultRow",
+     /*  31 */ "CollSeq",
+     /*  32 */ "AddImm",
+     /*  33 */ "MustBeInt",
+     /*  34 */ "RealAffinity",
+     /*  35 */ "Permutation",
+     /*  36 */ "Compare",
+     /*  37 */ "Jump",
+     /*  38 */ "Once",
+     /*  39 */ "If",
+     /*  40 */ "IfNot",
+     /*  41 */ "Column",
+     /*  42 */ "Affinity",
+     /*  43 */ "MakeRecord",
+     /*  44 */ "Count",
+     /*  45 */ "ReadCookie",
+     /*  46 */ "SetCookie",
+     /*  47 */ "VerifyCookie",
+     /*  48 */ "OpenRead",
+     /*  49 */ "OpenWrite",
+     /*  50 */ "OpenAutoindex",
+     /*  51 */ "OpenEphemeral",
+     /*  52 */ "SorterOpen",
+     /*  53 */ "OpenPseudo",
+     /*  54 */ "Close",
+     /*  55 */ "SeekLt",
+     /*  56 */ "SeekLe",
+     /*  57 */ "SeekGe",
+     /*  58 */ "SeekGt",
+     /*  59 */ "Seek",
+     /*  60 */ "NotFound",
+     /*  61 */ "Found",
+     /*  62 */ "IsUnique",
+     /*  63 */ "NotExists",
+     /*  64 */ "Sequence",
+     /*  65 */ "NewRowid",
+     /*  66 */ "Insert",
+     /*  67 */ "InsertInt",
+     /*  68 */ "Or",
+     /*  69 */ "And",
+     /*  70 */ "Delete",
+     /*  71 */ "ResetCount",
+     /*  72 */ "SorterCompare",
+     /*  73 */ "IsNull",
+     /*  74 */ "NotNull",
+     /*  75 */ "Ne",
+     /*  76 */ "Eq",
+     /*  77 */ "Gt",
+     /*  78 */ "Le",
+     /*  79 */ "Lt",
+     /*  80 */ "Ge",
+     /*  81 */ "SorterData",
+     /*  82 */ "BitAnd",
+     /*  83 */ "BitOr",
+     /*  84 */ "ShiftLeft",
+     /*  85 */ "ShiftRight",
+     /*  86 */ "Add",
+     /*  87 */ "Subtract",
+     /*  88 */ "Multiply",
+     /*  89 */ "Divide",
+     /*  90 */ "Remainder",
+     /*  91 */ "Concat",
+     /*  92 */ "RowKey",
+     /*  93 */ "BitNot",
+     /*  94 */ "String8",
+     /*  95 */ "RowData",
+     /*  96 */ "Rowid",
+     /*  97 */ "NullRow",
+     /*  98 */ "Last",
+     /*  99 */ "SorterSort",
+     /* 100 */ "Sort",
+     /* 101 */ "Rewind",
+     /* 102 */ "SorterInsert",
+     /* 103 */ "IdxInsert",
+     /* 104 */ "IdxDelete",
+     /* 105 */ "IdxRowid",
+     /* 106 */ "IdxLT",
+     /* 107 */ "IdxGE",
+     /* 108 */ "Destroy",
+     /* 109 */ "Clear",
+     /* 110 */ "CreateIndex",
+     /* 111 */ "CreateTable",
+     /* 112 */ "ParseSchema",
+     /* 113 */ "LoadAnalysis",
+     /* 114 */ "DropTable",
+     /* 115 */ "DropIndex",
+     /* 116 */ "DropTrigger",
+     /* 117 */ "IntegrityCk",
+     /* 118 */ "RowSetAdd",
+     /* 119 */ "RowSetRead",
+     /* 120 */ "RowSetTest",
+     /* 121 */ "Program",
+     /* 122 */ "Param",
+     /* 123 */ "FkCounter",
+     /* 124 */ "FkIfZero",
+     /* 125 */ "MemMax",
+     /* 126 */ "IfPos",
+     /* 127 */ "IfNeg",
+     /* 128 */ "IfZero",
+     /* 129 */ "AggFinal",
+     /* 130 */ "Real",
+     /* 131 */ "IncrVacuum",
+     /* 132 */ "Expire",
+     /* 133 */ "TableLock",
+     /* 134 */ "VBegin",
+     /* 135 */ "VCreate",
+     /* 136 */ "VDestroy",
+     /* 137 */ "VOpen",
+     /* 138 */ "VColumn",
+     /* 139 */ "VNext",
+     /* 140 */ "VRename",
+     /* 141 */ "ToText",
+     /* 142 */ "ToBlob",
+     /* 143 */ "ToNumeric",
+     /* 144 */ "ToInt",
+     /* 145 */ "ToReal",
+     /* 146 */ "Pagecount",
+     /* 147 */ "MaxPgcnt",
+     /* 148 */ "Trace",
+     /* 149 */ "Noop",
+     /* 150 */ "Explain",
   };
-#endif
-
-  /* Double-check that the aSyscall[] array has been constructed
-  ** correctly.  See ticket [bb3a86e890c8e96ab] */
-  assert( ArraySize(aSyscall)==75 );
-
-  /* get memory map allocation granularity */
-  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
-#if SQLITE_OS_WINRT
-  osGetNativeSystemInfo(&winSysInfo);
-#else
-  osGetSystemInfo(&winSysInfo);
-#endif
-  assert( winSysInfo.dwAllocationGranularity>0 );
-  assert( winSysInfo.dwPageSize>0 );
-
-  sqlite3_vfs_register(&winVfs, 1);
-
-#if defined(SQLITE_WIN32_HAS_WIDE)
-  sqlite3_vfs_register(&winLongPathVfs, 0);
-#endif
-
-  return SQLITE_OK; 
+  return azName[i];
 }
-
-SQLITE_API int sqlite3_os_end(void){ 
-#if SQLITE_OS_WINRT
-  if( sleepObj!=NULL ){
-    osCloseHandle(sleepObj);
-    sleepObj = NULL;
-  }
 #endif
-  return SQLITE_OK;
-}
 
-#endif /* SQLITE_OS_WIN */
-
-/************** End of os_win.c **********************************************/
+/************** End of opcodes.c *********************************************/
 /************** Begin file os_rtt.c ******************************************/
 /*
 ** 2004 May 22
-- 
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