Updated for "Windows 10 Anniversary Update" (Version 1607)

1 files changed, 172 insertions, 0 deletions

diff --git a/AVStream/avscamera/sys/Timer.cpp b/AVStream/avscamera/sys/Timer.cpp
new file mode 100644
index 00000000..5345a361
--- /dev/null
+++ b/AVStream/avscamera/sys/Timer.cpp
@@ -0,0 +1,172 @@
+/**************************************************************************
+
+    A/V Stream Camera Sample
+
+    Copyright (c) 2014, Microsoft Corporation.
+
+    File:
+
+        timer.cpp
+
+    Abstract:
+
+        Contains the implementation of a KTimer and KPassiveTimer.
+
+        KTimer wraps a kernel timer object.  KPassiveTimer uses a passive
+        callback through a KWorkItem.
+
+    History:
+
+        created 5/30/2014
+
+**************************************************************************/
+
+#include "Common.h"
+
+KTimer::
+KTimer( TIMER_TYPE  type )
+    : m_Period(0)
+    , m_Context(NULL)
+    , m_Callback(NULL)
+{
+    KeInitializeTimerEx( &m_Timer,type ) ;
+    KeInitializeDpc( &m_Dpc, KTimer::DpcThunk, this ) ;
+}
+
+KTimer::
+~KTimer()
+{
+    Cancel();
+}
+
+//
+//  Cancels the timer and ensures no DPC is executing.
+//
+BOOLEAN
+KTimer::
+Cancel()
+{
+    //  Clear the timer and dequeue the DPC.
+    if( !Reset() )
+    {
+        //  If the item wasn't found, flush all the DPC queues.
+        KeFlushQueuedDpcs() ;
+
+        //  Return false because we lost the race.
+        return FALSE;
+    }
+    return TRUE;
+}
+
+//
+//  Support for waitable class
+//
+PVOID
+KTimer::
+GetDispatchObject()
+{
+    return &m_Timer;
+}
+
+//
+//  Dpc Thunking function for KeSetTimerEx
+//
+_Function_class_(KDEFERRED_ROUTINE)
+VOID
+KTimer::
+DpcThunk(
+    _In_        PKDPC   /*Dpc*/,
+    _Inout_opt_ PVOID   DeferredContext,
+    _Inout_opt_ PVOID   /*Arg1*/,
+    _Inout_opt_ PVOID   /*Arg2*/
+)
+{
+    KTimer *pKTimer = (KTimer *) DeferredContext ;
+    pKTimer->Func() ;
+}
+
+//
+//  Function invoked when a timer expires
+//
+//  IRQL <= DISPATCH_LEVEL
+//
+void
+KTimer::
+Func()
+{
+    if( m_Callback )
+    {
+        m_Callback( m_Context ) ;
+    }
+}
+
+//
+//  Dtor
+//
+//  Calls Cancel() here to clean up.
+//
+//  Note: KTimer will also call Cancel(), but it will invoke KTimer::Cancel().
+//        Since KPassiveTimer::Cancel() first calls KTimer::Cancel() this second
+//        call is redudant; but preventing it would probably require an explicit
+//        call to Cancel() before destruction.  This way you can just delete
+//        timers when they are no longer needed, but it make take a bit longer.
+//
+KPassiveTimer::
+~KPassiveTimer()
+{
+    Cancel();
+}
+
+//
+//  Function invoked when a timer expires
+//
+//  IRQL == DISPATCH_LEVEL
+//
+void
+KPassiveTimer::
+Func()
+{
+    if( m_Callback )
+    {
+        //  Start the work item.  If it fails, there's not much we can do since
+        //  it can only fail if the owner of this timer is trying to cancel it.
+        m_WorkItem.Start();
+    }
+}
+
+VOID
+KPassiveTimer::
+WorkThunk(
+    _In_ PDEVICE_OBJECT DeviceObject,
+    _In_opt_ PVOID Context
+)
+{
+    UNREFERENCED_PARAMETER(DeviceObject);
+
+    if( Context )
+    {
+        ((KPassiveTimer *) Context)->KTimer::Func();
+    }
+}
+
+//
+//  Cancels the timer
+//
+BOOLEAN
+KPassiveTimer::
+Cancel()
+{
+    //  Kill the timer.
+    if( !KTimer::Cancel() )
+    {
+        //  Wait until the work item is idle.
+        m_WorkItem.Wait();
+
+        //  Reset the WorkItem so we can use it again.
+        m_WorkItem.Reset();
+
+        return FALSE;
+    }
+    return TRUE;
+}
+