Add memtrace command for memheap.c

31 files changed, 807 insertions, 461 deletions

diff --git a/components/libc/compilers/armlibc/README.md b/components/libc/compilers/armlibc/README.md
new file mode 100644
index 0000000000..4d2a73b6be
--- /dev/null
+++ b/components/libc/compilers/armlibc/README.md
@@ -0,0 +1,9 @@
+# ARMLIB (Keil-MDK) porting for RT-Thread
+
+Please define RT_USING_LIBC and compile RT-Thread with Keil-MDK compiler.
+
+
+
+## More Information
+
+https://www.keil.com/support/man/docs/armlib/
\ No newline at end of file
diff --git a/components/libc/compilers/armlibc/fcntl.h b/components/libc/compilers/armlibc/fcntl.h
index 80cf1b4409..3e650a8471 100644
--- a/components/libc/compilers/armlibc/fcntl.h
+++ b/components/libc/compilers/armlibc/fcntl.h
@@ -9,6 +9,8 @@
 #ifndef FCNTL_H__
 #define FCNTL_H__
 
+#include <rtconfig.h>
+
 #ifdef RT_USING_DFS
 #include <dfs_posix.h>
 #endif
diff --git a/components/libc/compilers/armlibc/libc_syms.c b/components/libc/compilers/armlibc/libc_syms.c
index 0e1c42d899..a2e8af17f1 100644
--- a/components/libc/compilers/armlibc/libc_syms.c
+++ b/components/libc/compilers/armlibc/libc_syms.c
@@ -10,8 +10,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
-#include <time.h>
-
 #include <rtm.h>
 
 /* some export routines for module */
@@ -35,11 +33,6 @@ RTM_EXPORT(memchr);
 RTM_EXPORT(toupper);
 RTM_EXPORT(atoi);
 
-#ifdef RT_USING_RTC
-RTM_EXPORT(localtime);
-RTM_EXPORT(time);
-#endif
-
 /* import the full stdio for printf */
 #if defined(RT_USING_MODULE) && defined(__MICROLIB)
 #error "[RT_USING_LIBC] Please use standard libc but not microlib."
diff --git a/components/libc/compilers/armlibc/termios.h b/components/libc/compilers/armlibc/sys/ioctl.h
index 1956121225..033a57014a 100644
--- a/components/libc/compilers/armlibc/termios.h
+++ b/components/libc/compilers/armlibc/sys/ioctl.h
@@ -5,11 +5,11 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-09-01     Meco Man     First Version
  */
-#ifndef _TERMIOS_H__
-#define _TERMIOS_H__
+#ifndef _SYS_IOCTL_H
+#define _SYS_IOCTL_H
+
 
-#include <sys/types.h>
-#include <posix_termios.h>
 
 #endif
diff --git a/components/libc/compilers/armlibc/sys/types.h b/components/libc/compilers/armlibc/sys/types.h
index 001ace4dd2..d1e457b36f 100644
--- a/components/libc/compilers/armlibc/sys/types.h
+++ b/components/libc/compilers/armlibc/sys/types.h
@@ -5,20 +5,24 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-09-05     Meco Man     fix bugs
+ * 2020-12-16     Meco Man     add useconds_t
  */
 #ifndef __TYPES_H__
 #define __TYPES_H__
 
 #include <stdint.h>
-#include <rtthread.h>
 
-typedef rt_int32_t clockid_t;
-typedef rt_int32_t key_t;       /* Used for interprocess communication. */
-typedef rt_int32_t pid_t;       /* Used for process IDs and process group IDs. */
+typedef int32_t          clockid_t;
+typedef int32_t          key_t;         /* Used for interprocess communication. */
+typedef int              pid_t;         /* Used for process IDs and process group IDs. */
+typedef unsigned short   uid_t;
+typedef unsigned short   gid_t;
 #ifndef ARCH_CPU_64BIT
-typedef signed int   ssize_t;  /* Used for a count of bytes or an error indication. */
+typedef signed int       ssize_t;       /* Used for a count of bytes or an error indication. */
 #else
-typedef long signed int   ssize_t;  /* Used for a count of bytes or an error indication. */
+typedef long signed int  ssize_t;       /* Used for a count of bytes or an error indication. */
 #endif
+typedef unsigned long    useconds_t;    /* microseconds (unsigned) */
 
 #endif
diff --git a/components/libc/compilers/armlibc/sys/unistd.h b/components/libc/compilers/armlibc/sys/unistd.h
index 33f0561e72..ee1e1c4db9 100644
--- a/components/libc/compilers/armlibc/sys/unistd.h
+++ b/components/libc/compilers/armlibc/sys/unistd.h
@@ -5,11 +5,13 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-12-16     Meco Man     add usleep
  */
 #ifndef _SYS_UNISTD_H
 #define _SYS_UNISTD_H
 
-#include <rtthread.h>
+#include <rtconfig.h>
+#include "types.h"
 
 #ifdef RT_USING_DFS
 
@@ -36,14 +38,46 @@
 #define _FNDELAY    _FNONBLOCK  /* non blocking I/O (4.2 style) */
 #define _FNOCTTY    0x8000  /* don't assign a ctty on this open */
 
+
+#ifndef O_RDONLY
 #define O_RDONLY    0       /* +1 == FREAD */
+#endif
+#ifndef O_WRONLY
 #define O_WRONLY    1       /* +1 == FWRITE */
+#endif
+#ifndef O_RDWR
 #define O_RDWR      2       /* +1 == FREAD|FWRITE */
+#endif
+#ifndef O_APPEND
 #define O_APPEND    _FAPPEND
+#endif
+#ifndef O_CREAT
 #define O_CREAT     _FCREAT
+#endif
+#ifndef O_TRUNC
 #define O_TRUNC     _FTRUNC
+#endif
+#ifndef O_EXCL
 #define O_EXCL      _FEXCL
+#endif
+#ifndef O_SYNC
 #define O_SYNC      _FSYNC
 #endif
 
+#endif
+
+
+int     isatty      (int fd);
+char *  ttyname     (int desc);
+
+unsigned int sleep(unsigned int seconds);
+int usleep(useconds_t usec);
+
+pid_t getpid(void);
+pid_t getppid(void);
+uid_t getuid(void);
+uid_t geteuid(void);
+gid_t getgid(void);
+gid_t getegid(void);
+
 #endif /* _SYS_UNISTD_H */
diff --git a/components/libc/compilers/armlibc/stubs.c b/components/libc/compilers/armlibc/syscalls.c
index b6ffb37b0f..8addb3e163 100644
--- a/components/libc/compilers/armlibc/stubs.c
+++ b/components/libc/compilers/armlibc/syscalls.c
@@ -9,16 +9,21 @@
  * 2013-11-24     aozima       fixed _sys_read()/_sys_write() issues.
  * 2014-08-03     bernard      If using msh, use system() implementation
  *                             in msh.
+ * 2020-08-05     Meco Man     fixed _sys_flen() compiling-warning when 
+ *                             RT_USING_DFS is not defined
+ * 2020-02-13     Meco Man     re-implement exit() and abort()
+ * 2020-02-14     Meco Man     implement _sys_tmpnam()
+ * 2020-02-25     Meco Man     add multithreaded protection
  */
 
 #include <string.h>
 #include <rt_sys.h>
 
-#include "rtthread.h"
+#include <rtthread.h>
 #include "libc.h"
 
 #ifdef RT_USING_DFS
-#include "dfs_posix.h"
+#include <dfs_posix.h>
 #endif
 
 #ifdef __CLANG_ARM
@@ -37,6 +42,36 @@ const char __stdin_name[]  = "STDIN";
 const char __stdout_name[] = "STDOUT";
 const char __stderr_name[] = "STDERR";
 
+#ifdef RT_USING_HEAP
+int _mutex_initialize(rt_mutex_t *m)
+{
+    *m = rt_mutex_create("_mutex_", RT_IPC_FLAG_PRIO);
+    if(*m == RT_NULL)
+    {
+        return 0;
+    }
+    else
+    {
+        return 1;
+    }
+}
+
+void _mutex_acquire(rt_mutex_t *m)
+{
+    rt_mutex_take(*m, RT_WAITING_FOREVER);
+}
+
+void _mutex_release(rt_mutex_t *m)
+{
+    rt_mutex_release(*m);
+}
+
+void _mutex_free(rt_mutex_t *m)
+{
+    rt_mutex_delete(*m);
+}
+#endif
+
 /**
  * required by fopen() and freopen().
  *
@@ -231,7 +266,8 @@ int _sys_seek(FILEHANDLE fh, long pos)
  */
 int _sys_tmpnam(char *name, int fileno, unsigned maxlength)
 {
-    return -1;
+    rt_snprintf(name, maxlength, "tem%03d", fileno);
+    return 1;
 }
 
 char *_sys_command_string(char *cmd, int len)
@@ -251,10 +287,12 @@ void _ttywrch(int ch)
 #endif
 }
 
+/* for exit() and abort() */
 RT_WEAK void _sys_exit(int return_code)
 {
-    /* TODO: perhaps exit the thread which is invoking this function */
-    while (1);
+    extern void __rt_libc_exit(int status);
+    __rt_libc_exit(return_code);
+    while(1);
 }
 
 /**
@@ -265,16 +303,16 @@ RT_WEAK void _sys_exit(int return_code)
  */
 long _sys_flen(FILEHANDLE fh)
 {
+#ifdef RT_USING_DFS
     struct stat stat;
-    
+
     if (fh < STDERR)
         return -1;
 
-#ifndef RT_USING_DFS
-    return -1;
-#else
     fstat(fh, &stat);
     return stat.st_size;
+#else
+    return -1;
 #endif
 }
 
@@ -300,8 +338,8 @@ int remove(const char *filename)
 #else
 int system(const char *string)
 {
-    RT_ASSERT(0);
-    for (;;);
+    extern int __rt_libc_system(const char *string);
+    return __rt_libc_system(string);
 }
 #endif
 
diff --git a/components/libc/compilers/armlibc/unistd.h b/components/libc/compilers/armlibc/unistd.h
index 70187722d8..736fc219a8 100644
--- a/components/libc/compilers/armlibc/unistd.h
+++ b/components/libc/compilers/armlibc/unistd.h
@@ -7,3 +7,4 @@
  * Date           Author       Notes
  */
 #include "sys/unistd.h"
+
diff --git a/components/libc/compilers/common/SConscript b/components/libc/compilers/common/SConscript
index a8d2606820..ecdee2637e 100644
--- a/components/libc/compilers/common/SConscript
+++ b/components/libc/compilers/common/SConscript
@@ -8,12 +8,20 @@ group = []
 CPPPATH = [cwd]
 
 if GetDepend('RT_USING_LIBC'):
-        src += Glob('*.c')
+    src += Glob('*.c')
 else:
-        if GetDepend('RT_LIBC_USING_TIME'):
-                src += ['time.c']
+    if GetDepend('RT_LIBC_USING_TIME') and not GetDepend('RT_USING_MINILIBC'):
+        src += ['time.c']
 
-if (rtconfig.PLATFORM == 'armcc' or rtconfig.PLATFORM == 'iar') and rtconfig.ARCH != 'sim' :
-        group = DefineGroup('libc', src, depend = [''], CPPPATH = CPPPATH)
+if GetDepend('RT_USING_POSIX') == False:
+    SrcRemove(src, ['unistd.c'])
+
+if rtconfig.CROSS_TOOL == 'keil':
+    CPPDEFINES = ['__CLK_TCK=RT_TICK_PER_SECOND']
+else:
+    CPPDEFINES = []
+
+if not GetDepend('RT_USING_MINILIBC') and (GetDepend('RT_USING_LIBC') or GetDepend('RT_LIBC_USING_TIME')):
+    group = DefineGroup('libc', src, depend = [''], CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES)
 
 Return('group')
diff --git a/components/libc/compilers/common/readme.md b/components/libc/compilers/common/readme.md
new file mode 100644
index 0000000000..81bb005d0a
--- /dev/null
+++ b/components/libc/compilers/common/readme.md
@@ -0,0 +1,10 @@
+## Attentions
+
+1. This folder is "common" for armlibc newlibc and dlib.
+
+2. If you want to add new `.c` files, please do not forget to fix SConscript file too. eg:
+
+```python
+if GetDepend('RT_USING_POSIX') == False:
+        SrcRemove(src, ['unistd.c'])
+```
\ No newline at end of file
diff --git a/components/libc/compilers/common/stdlib.c b/components/libc/compilers/common/stdlib.c
new file mode 100644
index 0000000000..48a86098cd
--- /dev/null
+++ b/components/libc/compilers/common/stdlib.c
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-02-15     Meco Man     first version
+ */
+
+#include <rtthread.h>
+
+void __rt_libc_exit(int status)
+{
+    rt_thread_t self = rt_thread_self();
+
+    if (self != RT_NULL)
+    {
+        rt_kprintf("thread:%s exit:%d!\n", self->name, status);
+        rt_thread_control(self, RT_THREAD_CTRL_CLOSE, RT_NULL);
+    }
+}
+
+int __rt_libc_system(const char *string)
+{
+    /* TODO */
+    return 0;
+}
diff --git a/components/libc/compilers/common/sys/time.h b/components/libc/compilers/common/sys/time.h
index 1d68eeafa3..e4d60d2d11 100644
--- a/components/libc/compilers/common/sys/time.h
+++ b/components/libc/compilers/common/sys/time.h
@@ -5,16 +5,27 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-09-07     Meco Man     combine gcc armcc iccarm
+ * 2021-02-12     Meco Man     move all definitions located in <clock_time.h> to this file
  */
 #ifndef _SYS_TIME_H_
 #define _SYS_TIME_H_
 
+#include <rtconfig.h>
 #include <time.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+/*
+ * Skip define timespec for IAR version over 8.10.1 where __VER__ is 8010001.
+ */
+#if defined ( __ICCARM__ ) && (__VER__ >= 8010001)
+#define _TIMESPEC_DEFINED
+#endif
+
+
 #ifndef _TIMEVAL_DEFINED
 #define _TIMEVAL_DEFINED
 /*
@@ -27,31 +38,56 @@ struct timeval {
 };
 #endif /* _TIMEVAL_DEFINED */
 
-/*
- * Skip define timespec for IAR version over 8.10.1 where __VER__ is 8010001.
- */
-#if defined ( __ICCARM__ ) && (__VER__ >= 8010001)
-#define _TIMESPEC_DEFINED
-#endif
-
-#ifndef _TIMESPEC_DEFINED
-#define _TIMESPEC_DEFINED
-/*
- * Structure defined by POSIX.1b to be like a timeval.
- */
+#if !defined __GNUC__ && !defined __ICCARM__
 struct timespec {
     time_t  tv_sec;     /* seconds */
     long    tv_nsec;    /* and nanoseconds */
 };
-#endif /* _TIMESPEC_DEFINED */ 
+#endif
 
 struct timezone {
   int tz_minuteswest;   /* minutes west of Greenwich */
   int tz_dsttime;       /* type of dst correction */
 };
 
-int gettimeofday(struct timeval *tp, void *ignore);
-struct tm *gmtime_r(const time_t *timep, struct tm *r);
+int stime(const time_t *t);
+time_t timegm(struct tm * const t);
+int gettimeofday(struct timeval *tv, struct timezone *tz);
+int settimeofday(const struct timeval *tv, const struct timezone *tz);
+
+#ifdef RT_USING_POSIX
+#include <sys/types.h>
+/* posix clock and timer */
+#define MILLISECOND_PER_SECOND  1000UL
+#define MICROSECOND_PER_SECOND  1000000UL
+#define NANOSECOND_PER_SECOND   1000000000UL
+
+#define MILLISECOND_PER_TICK    (MILLISECOND_PER_SECOND / RT_TICK_PER_SECOND)
+#define MICROSECOND_PER_TICK    (MICROSECOND_PER_SECOND / RT_TICK_PER_SECOND)
+#define NANOSECOND_PER_TICK     (NANOSECOND_PER_SECOND  / RT_TICK_PER_SECOND)
+
+#ifndef CLOCK_REALTIME
+#define CLOCK_REALTIME      1
+#endif
+
+#define CLOCK_CPUTIME_ID    2
+
+#ifndef CLOCK_PROCESS_CPUTIME_ID
+#define CLOCK_PROCESS_CPUTIME_ID CLOCK_CPUTIME_ID
+#endif
+#ifndef CLOCK_THREAD_CPUTIME_ID
+#define CLOCK_THREAD_CPUTIME_ID  CLOCK_CPUTIME_ID
+#endif
+
+#ifndef CLOCK_MONOTONIC
+#define CLOCK_MONOTONIC     4
+#endif
+
+int clock_getres  (clockid_t clockid, struct timespec *res);
+int clock_gettime (clockid_t clockid, struct timespec *tp);
+int clock_settime (clockid_t clockid, const struct timespec *tp);
+int clock_time_to_tick(const struct timespec *time);
+#endif /* RT_USING_POSIX */
 
 #ifdef __cplusplus
 }
diff --git a/components/libc/compilers/newlib/termios.h b/components/libc/compilers/common/termios.h
index 1956121225..414d0c0cb3 100644
--- a/components/libc/compilers/newlib/termios.h
+++ b/components/libc/compilers/common/termios.h
@@ -9,7 +9,11 @@
 #ifndef _TERMIOS_H__
 #define _TERMIOS_H__
 
+#include <rtconfig.h>
+
+#ifdef RT_USING_POSIX_TERMIOS
 #include <sys/types.h>
 #include <posix_termios.h>
+#endif
 
 #endif
diff --git a/components/libc/compilers/common/time.c b/components/libc/compilers/common/time.c
index 50a800b259..c2fbd6f333 100644
--- a/components/libc/compilers/common/time.c
+++ b/components/libc/compilers/common/time.c
@@ -6,15 +6,30 @@
  * Change Logs:
  * Date           Author       Notes
  * 2019-08-21     zhangjun     copy from minilibc
+ * 2020-09-07     Meco Man     combine gcc armcc iccarm
+ * 2021-02-05     Meco Man     add timegm()
+ * 2021-02-07     Meco Man     fixed gettimeofday()
+ * 2021-02-08     Meco Man     add settimeofday() stime()
+ * 2021-02-10     Meco Man     add ctime_r() and re-implement ctime()
+ * 2021-02-11     Meco Man     fix bug #3183 - align days[] and months[] to 4 bytes
+ *                             add difftime()
+ * 2021-02-12     Meco Man     add errno
+ * 2012-12-08     Bernard      <clock_time.c> fix the issue of _timevalue.tv_usec initialization,
+ *                             which found by Rob <[email protected]>
+ * 2021-02-12     Meco Man     move all of the functions located in <clock_time.c> to this file
  */
 
 #include <sys/time.h>
 #include <rtthread.h>
+#ifdef RT_USING_DEVICE
+#include <rtdevice.h>
+#endif
 
-#if !defined (__IAR_SYSTEMS_ICC__)
+/* seconds per day */
+#define SPD 24*60*60
 
 /* days per month -- nonleap! */
-const short __spm[13] =
+static const short __spm[13] =
 {
     0,
     (31),
@@ -30,13 +45,11 @@ const short __spm[13] =
     (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30),
     (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31),
 };
-static const char days[] = "Sun Mon Tue Wed Thu Fri Sat ";
-static const char months[] = "Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ";
 
-/* seconds per day */
-#define SPD 24*60*60
+ALIGN(4) static const char days[] = "Sun Mon Tue Wed Thu Fri Sat ";
+ALIGN(4) static const char months[] = "Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ";
 
-int __isleap(int year)
+static int __isleap(int year)
 {
     /* every fourth year is a leap year except for century years that are
      * not divisible by 400. */
@@ -44,6 +57,12 @@ int __isleap(int year)
     return (!(year % 4) && ((year % 100) || !(year % 400)));
 }
 
+static void num2str(char *c, int i)
+{
+    c[0] = i / 10 + '0';
+    c[1] = i % 10 + '0';
+}
+
 struct tm *gmtime_r(const time_t *timep, struct tm *r)
 {
     time_t i;
@@ -77,29 +96,175 @@ struct tm *gmtime_r(const time_t *timep, struct tm *r)
         ;
     r->tm_mon = i;
     r->tm_mday += work - __spm[i];
+
+    r->tm_isdst = 0;
     return r;
 }
+RTM_EXPORT(gmtime_r);
 
 struct tm* gmtime(const time_t* t)
 {
     static struct tm tmp;
     return gmtime_r(t, &tmp);
 }
+RTM_EXPORT(gmtime);
 
-/*TODO timezone is not supprt now */
+/*TODO: timezone */
 struct tm* localtime_r(const time_t* t, struct tm* r)
 {
-    return gmtime_r(t, r);
+    time_t local_tz;
+    int utc_plus;
+
+    utc_plus = 0; /* GTM: UTC+0 */
+    local_tz = *t + utc_plus * 3600;
+    return gmtime_r(&local_tz, r);
 }
+RTM_EXPORT(localtime_r);
 
 struct tm* localtime(const time_t* t)
 {
     static struct tm tmp;
     return localtime_r(t, &tmp);
 }
+RTM_EXPORT(localtime);
 
+/* TODO: timezone */
 time_t mktime(struct tm * const t)
 {
+    return timegm(t);
+}
+RTM_EXPORT(mktime);
+
+char* asctime_r(const struct tm *t, char *buf)
+{
+    /* "Wed Jun 30 21:49:08 1993\n" */
+    *(int*) buf = *(int*) (days + (t->tm_wday << 2));
+    *(int*) (buf + 4) = *(int*) (months + (t->tm_mon << 2));
+    num2str(buf + 8, t->tm_mday);
+    if (buf[8] == '0')
+        buf[8] = ' ';
+    buf[10] = ' ';
+    num2str(buf + 11, t->tm_hour);
+    buf[13] = ':';
+    num2str(buf + 14, t->tm_min);
+    buf[16] = ':';
+    num2str(buf + 17, t->tm_sec);
+    buf[19] = ' ';
+    num2str(buf + 20, (t->tm_year + 1900) / 100);
+    num2str(buf + 22, (t->tm_year + 1900) % 100);
+    buf[24] = '\n';
+    return buf;
+}
+RTM_EXPORT(asctime_r);
+
+char* asctime(const struct tm *timeptr)
+{
+    static char buf[25];
+    return asctime_r(timeptr, buf);
+}
+RTM_EXPORT(asctime);
+
+char *ctime_r (const time_t * tim_p, char * result)
+{
+    struct tm tm;
+    return asctime_r (localtime_r (tim_p, &tm), result);
+}
+RTM_EXPORT(ctime_r);
+
+char* ctime(const time_t *tim_p)
+{
+    return asctime (localtime (tim_p));
+}
+RTM_EXPORT(ctime);
+
+double difftime (time_t tim1, time_t tim2)
+{
+    return (double)(tim1 - tim2);
+}
+RTM_EXPORT(difftime);
+
+/**
+ * Returns the current time.
+ *
+ * @param time_t * t the timestamp pointer, if not used, keep NULL.
+ *
+ * @return The value ((time_t)-1) is returned if the calendar time is not available. 
+ *         If timer is not a NULL pointer, the return value is also stored in timer.
+ *
+ */
+RT_WEAK time_t time(time_t *t)
+{
+    time_t time_now = ((time_t)-1); /* default is not available */
+
+#ifdef RT_USING_RTC
+    static rt_device_t device = RT_NULL;
+
+    /* optimization: find rtc device only first */
+    if (device == RT_NULL)
+    {
+        device = rt_device_find("rtc");
+    }
+
+    /* read timestamp from RTC device */
+    if (device != RT_NULL)
+    {
+        if (rt_device_open(device, 0) == RT_EOK)
+        {
+            rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time_now);
+            rt_device_close(device);
+        }
+    }
+#endif /* RT_USING_RTC */
+
+    /* if t is not NULL, write timestamp to *t */
+    if (t != RT_NULL)
+    {
+        *t = time_now;
+    }
+
+    if(time_now == (time_t)-1)
+    {
+        errno = ENOSYS;
+    }
+
+    return time_now;
+}
+RTM_EXPORT(time);
+
+RT_WEAK clock_t clock(void)
+{
+    return rt_tick_get();
+}
+RTM_EXPORT(clock);
+
+int stime(const time_t *t)
+{
+#ifdef RT_USING_RTC
+    rt_device_t device;
+
+    /* read timestamp from RTC device. */
+    device = rt_device_find("rtc");
+    if (rt_device_open(device, 0) == RT_EOK)
+    {
+        rt_device_control(device, RT_DEVICE_CTRL_RTC_SET_TIME, (void*)t);
+        rt_device_close(device);
+    }
+    else
+    {
+        errno = ENOSYS;
+        return -1;
+    }
+    return 0;
+
+#else
+    errno = ENOSYS;
+    return -1;
+#endif /* RT_USING_RTC */
+}
+RTM_EXPORT(stime);
+
+time_t timegm(struct tm * const t)
+{
     register time_t day;
     register time_t i;
     register time_t years = t->tm_year - 70;
@@ -171,121 +336,214 @@ time_t mktime(struct tm * const t)
     i = 60;
     return ((day + t->tm_hour) * i + t->tm_min) * i + t->tm_sec;
 }
+RTM_EXPORT(timegm);
 
-static void num2str(char *c, int i)
-{
-    c[0] = i / 10 + '0';
-    c[1] = i % 10 + '0';
-}
-
-char* asctime_r(const struct tm *t, char *buf)
+/* TODO: timezone */
+int gettimeofday(struct timeval *tv, struct timezone *tz)
 {
-    /* "Wed Jun 30 21:49:08 1993\n" */
-    *(int*) buf = *(int*) (days + (t->tm_wday << 2));
-    *(int*) (buf + 4) = *(int*) (months + (t->tm_mon << 2));
-    num2str(buf + 8, t->tm_mday);
-    if (buf[8] == '0')
-        buf[8] = ' ';
-    buf[10] = ' ';
-    num2str(buf + 11, t->tm_hour);
-    buf[13] = ':';
-    num2str(buf + 14, t->tm_min);
-    buf[16] = ':';
-    num2str(buf + 17, t->tm_sec);
-    buf[19] = ' ';
-    num2str(buf + 20, (t->tm_year + 1900) / 100);
-    num2str(buf + 22, (t->tm_year + 1900) % 100);
-    buf[24] = '\n';
-    return buf;
-}
+    time_t t = time(RT_NULL);
 
-char* asctime(const struct tm *timeptr)
-{
-    static char buf[25];
-    return asctime_r(timeptr, buf);
+    if (tv != RT_NULL && t != (time_t)-1)
+    {
+        tv->tv_sec = t;
+        tv->tv_usec = 0;
+        return 0;
+    }
+    else
+    {
+        errno = ENOSYS;
+        return -1;
+    }
 }
+RTM_EXPORT(gettimeofday);
 
-char* ctime(const time_t *timep)
+/* TODO: timezone */
+int settimeofday(const struct timeval *tv, const struct timezone *tz)
 {
-    return asctime(localtime(timep));
+    if (tv != RT_NULL)
+    {
+        return stime((const time_t *)&tv->tv_sec);
+    }
+    else
+    {
+        errno = ENOSYS;
+        return -1;
+    }
 }
+RTM_EXPORT(settimeofday);
 
-#endif /* __IAR_SYSTEMS_ICC__ */
-
-int gettimeofday(struct timeval *tp, void *ignore)
+#ifdef RT_USING_POSIX
+static struct timeval _timevalue;
+static int clock_time_system_init()
 {
-    time_t time = 0;
-#ifdef RT_USING_DEVICE
+    time_t time;
+    rt_tick_t tick;
     rt_device_t device;
+
+    time = 0;
     device = rt_device_find("rtc");
-    RT_ASSERT(device != RT_NULL);
-    rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
-    if (tp != RT_NULL)
+    if (device != RT_NULL)
     {
-        tp->tv_sec = time;
-        tp->tv_usec = 0;
+        /* get realtime seconds */
+        rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
     }
-#else
-    tv->tv_sec = 0;
-    tv->tv_usec = 0;
-#endif
 
-    return time;
+    /* get tick */
+    tick = rt_tick_get();
+
+    _timevalue.tv_usec = (tick%RT_TICK_PER_SECOND) * MICROSECOND_PER_TICK;
+    _timevalue.tv_sec = time - tick/RT_TICK_PER_SECOND - 1;
+
+    return 0;
 }
+INIT_COMPONENT_EXPORT(clock_time_system_init);
 
+int clock_getres(clockid_t clockid, struct timespec *res)
+{
+    int ret = 0;
 
-/**
- * Returns the current time.
- *
- * @param time_t * t the timestamp pointer, if not used, keep NULL.
- *
- * @return time_t return timestamp current.
- *
- */
-/* for IAR 6.2 later Compiler */
-#if defined (__IAR_SYSTEMS_ICC__) &&  (__VER__) >= 6020000
-#pragma module_name = "?time"
-#if _DLIB_TIME_USES_64
-time_t __time64(time_t *t) 
-#else
-time_t __time32(time_t *t) 
-#endif
-#else
-time_t time(time_t *t)
+    if (res == RT_NULL)
+    {
+        rt_set_errno(EINVAL);
+        return -1;
+    }
+
+    switch (clockid)
+    {
+    case CLOCK_REALTIME:
+        res->tv_sec = 0;
+        res->tv_nsec = NANOSECOND_PER_SECOND/RT_TICK_PER_SECOND;
+        break;
+
+#ifdef RT_USING_CPUTIME
+    case CLOCK_CPUTIME_ID:
+        res->tv_sec  = 0;
+        res->tv_nsec = clock_cpu_getres();
+        break;
 #endif
-{
-    time_t time_now = 0;
 
-#ifdef RT_USING_RTC
-    static rt_device_t device = RT_NULL;
+    default:
+        ret = -1;
+        rt_set_errno(EINVAL);
+        break;
+    }
 
-    /* optimization: find rtc device only first. */
-    if (device == RT_NULL)
+    return ret;
+}
+RTM_EXPORT(clock_getres);
+
+int clock_gettime(clockid_t clockid, struct timespec *tp)
+{
+    int ret = 0;
+
+    if (tp == RT_NULL)
     {
-        device = rt_device_find("rtc");
+        rt_set_errno(EINVAL);
+        return -1;
     }
 
-    /* read timestamp from RTC device. */
-    if (device != RT_NULL)
+    switch (clockid)
     {
-        if (rt_device_open(device, 0) == RT_EOK)
+    case CLOCK_REALTIME:
         {
-            rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time_now);
-            rt_device_close(device);
+            /* get tick */
+            int tick = rt_tick_get();
+
+            tp->tv_sec  = _timevalue.tv_sec + tick / RT_TICK_PER_SECOND;
+            tp->tv_nsec = (_timevalue.tv_usec + (tick % RT_TICK_PER_SECOND) * MICROSECOND_PER_TICK) * 1000;
+        }
+        break;
+
+#ifdef RT_USING_CPUTIME
+    case CLOCK_CPUTIME_ID:
+        {
+            float unit = 0;
+            long long cpu_tick;
+
+            unit = clock_cpu_getres();
+            cpu_tick = clock_cpu_gettime();
+
+            tp->tv_sec  = ((int)(cpu_tick * unit)) / NANOSECOND_PER_SECOND;
+            tp->tv_nsec = ((int)(cpu_tick * unit)) % NANOSECOND_PER_SECOND;
         }
+        break;
+#endif
+    default:
+        rt_set_errno(EINVAL);
+        ret = -1;
     }
-#endif /* RT_USING_RTC */
 
-    /* if t is not NULL, write timestamp to *t */
-    if (t != RT_NULL)
+    return ret;
+}
+RTM_EXPORT(clock_gettime);
+
+int clock_settime(clockid_t clockid, const struct timespec *tp)
+{
+    int second;
+    rt_tick_t tick;
+    rt_device_t device;
+
+    if ((clockid != CLOCK_REALTIME) || (tp == RT_NULL))
     {
-        *t = time_now;
+        rt_set_errno(EINVAL);
+
+        return -1;
     }
 
-    return time_now;
+    /* get second */
+    second = tp->tv_sec;
+    /* get tick */
+    tick = rt_tick_get();
+
+    /* update timevalue */
+    _timevalue.tv_usec = MICROSECOND_PER_SECOND - (tick % RT_TICK_PER_SECOND) * MICROSECOND_PER_TICK;
+    _timevalue.tv_sec = second - tick/RT_TICK_PER_SECOND - 1;
+
+    /* update for RTC device */
+    device = rt_device_find("rtc");
+    if (device != RT_NULL)
+    {
+        /* set realtime seconds */
+        rt_device_control(device, RT_DEVICE_CTRL_RTC_SET_TIME, &second);
+    }
+    else
+        return -1;
+
+    return 0;
 }
+RTM_EXPORT(clock_settime);
 
-RT_WEAK clock_t clock(void)
+int clock_time_to_tick(const struct timespec *time)
 {
-    return rt_tick_get();
+    int tick;
+    int nsecond, second;
+    struct timespec tp;
+
+    RT_ASSERT(time != RT_NULL);
+
+    tick = RT_WAITING_FOREVER;
+    if (time != NULL)
+    {
+        /* get current tp */
+        clock_gettime(CLOCK_REALTIME, &tp);
+
+        if ((time->tv_nsec - tp.tv_nsec) < 0)
+        {
+            nsecond = NANOSECOND_PER_SECOND - (tp.tv_nsec - time->tv_nsec);
+            second  = time->tv_sec - tp.tv_sec - 1;
+        }
+        else
+        {
+            nsecond = time->tv_nsec - tp.tv_nsec;
+            second  = time->tv_sec - tp.tv_sec;
+        }
+
+        tick = second * RT_TICK_PER_SECOND + nsecond * RT_TICK_PER_SECOND / NANOSECOND_PER_SECOND;
+        if (tick < 0) tick = 0;
+    }
+
+    return tick;
 }
+RTM_EXPORT(clock_time_to_tick);
+
+#endif /* RT_USING_POSIX */
diff --git a/components/libc/compilers/common/unistd.c b/components/libc/compilers/common/unistd.c
new file mode 100644
index 0000000000..0966242e55
--- /dev/null
+++ b/components/libc/compilers/common/unistd.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2020-09-01     Meco Man     first Version
+ * 2021-02-12     Meco Man     move all functions located in <pthread_sleep.c> to this file
+ */
+
+#include <unistd.h>
+#include <rtthread.h>
+#include <rthw.h>
+
+#ifdef RT_USING_POSIX_TERMIOS
+#include "termios.h"
+
+int isatty(int fd)
+{
+    struct termios ts;
+    return(tcgetattr(fd,&ts) != -1);/*true if no error (is a tty)*/
+}
+RTM_EXPORT(isatty);
+#endif
+
+char *ttyname(int fd)
+{
+    return "/dev/tty0"; /*TODO: need to add more specific*/
+}
+RTM_EXPORT(ttyname);
+
+unsigned int sleep(unsigned int seconds)
+{
+    rt_tick_t delta_tick;
+
+    delta_tick = rt_tick_get();
+    rt_thread_delay(seconds * RT_TICK_PER_SECOND);
+    delta_tick = rt_tick_get() - delta_tick;
+
+    return seconds - delta_tick/RT_TICK_PER_SECOND;
+}
+RTM_EXPORT(sleep);
+
+int usleep(useconds_t usec)
+{
+    rt_thread_mdelay(usec / 1000u);
+    rt_hw_us_delay(usec % 1000u);
+    return 0;
+}
+RTM_EXPORT(usleep);
+
+pid_t getpid(void)
+{
+    /*TODO*/
+    return 0;
+}
+RTM_EXPORT(getpid);
+
+pid_t getppid(void)
+{
+    return 0;
+}
+RTM_EXPORT(getppid);
+
+uid_t getuid(void)
+{
+    return 0; /*ROOT*/
+}
+RTM_EXPORT(getuid);
+
+uid_t geteuid(void)
+{
+    return 0; /*ROOT*/
+}
+RTM_EXPORT(geteuid);
+
+gid_t getgid(void)
+{
+    return 0; /*ROOT*/
+}
+RTM_EXPORT(getgid);
+
+gid_t getegid(void)
+{
+    return 0; /*ROOT*/
+}
+RTM_EXPORT(getegid);
diff --git a/components/libc/compilers/dlib/README.md b/components/libc/compilers/dlib/README.md
index 846eb3f5c0..acd08f9074 100644
--- a/components/libc/compilers/dlib/README.md
+++ b/components/libc/compilers/dlib/README.md
@@ -1,4 +1,9 @@
-Dlib(IAR) porting for RT-Thread.
+# DLIB (IAR) porting for RT-Thread
 
 Please define RT_USING_LIBC and compile RT-Thread with IAR compiler.
 
+
+
+## More Information
+
+http://www.iarsys.co.jp/download/LMS2/arm/7502/ewarm7502doc/arm/doc/EWARM_DevelopmentGuide.ENU.pdf    P.130
\ No newline at end of file
diff --git a/components/libc/compilers/dlib/SConscript b/components/libc/compilers/dlib/SConscript
index 456b762496..75a5812fab 100644
--- a/components/libc/compilers/dlib/SConscript
+++ b/components/libc/compilers/dlib/SConscript
@@ -20,7 +20,7 @@ if rtconfig.PLATFORM == 'iar':
         if LooseVersion(IARVersion()) < LooseVersion("8.20.1"):
             CPPDEFINES = CPPDEFINES + ['_DLIB_THREAD_SUPPORT']
 
-    group = DefineGroup('dlib', src, depend = ['RT_USING_LIBC'], 
+    group = DefineGroup('libc', src, depend = ['RT_USING_LIBC'], 
         CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES)
 
 Return('group')
diff --git a/components/libc/compilers/dlib/sys/types.h b/components/libc/compilers/dlib/sys/types.h
index 001ace4dd2..3af15ba251 100644
--- a/components/libc/compilers/dlib/sys/types.h
+++ b/components/libc/compilers/dlib/sys/types.h
@@ -5,20 +5,23 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-12-16     Meco Man     add useconds_t
  */
 #ifndef __TYPES_H__
 #define __TYPES_H__
 
 #include <stdint.h>
-#include <rtthread.h>
 
-typedef rt_int32_t clockid_t;
-typedef rt_int32_t key_t;       /* Used for interprocess communication. */
-typedef rt_int32_t pid_t;       /* Used for process IDs and process group IDs. */
+typedef int32_t          clockid_t;
+typedef int32_t          key_t;         /* Used for interprocess communication. */
+typedef int              pid_t;         /* Used for process IDs and process group IDs. */
+typedef unsigned short   uid_t;
+typedef unsigned short   gid_t;
 #ifndef ARCH_CPU_64BIT
-typedef signed int   ssize_t;  /* Used for a count of bytes or an error indication. */
+typedef signed int       ssize_t;       /* Used for a count of bytes or an error indication. */
 #else
-typedef long signed int   ssize_t;  /* Used for a count of bytes or an error indication. */
+typedef long signed int  ssize_t;       /* Used for a count of bytes or an error indication. */
 #endif
+typedef unsigned long    useconds_t;    /* microseconds (unsigned) */
 
 #endif
diff --git a/components/libc/compilers/dlib/sys/unistd.h b/components/libc/compilers/dlib/sys/unistd.h
index 29f68f24f8..5b86822635 100644
--- a/components/libc/compilers/dlib/sys/unistd.h
+++ b/components/libc/compilers/dlib/sys/unistd.h
@@ -5,10 +5,14 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2020-12-16     Meco Man     add usleep
  */
 #ifndef _SYS_UNISTD_H
 #define _SYS_UNISTD_H
 
+#include <rtconfig.h>
+#include "types.h"
+
 #ifdef RT_USING_DFS
 
 #define STDIN_FILENO    0       /* standard input file descriptor */
@@ -36,4 +40,18 @@
 
 #endif
 
+
+int     isatty      (int fd);
+char *  ttyname     (int desc);
+
+unsigned int sleep(unsigned int seconds);
+int usleep(useconds_t usec);
+
+pid_t getpid(void);
+pid_t getppid(void);
+uid_t getuid(void);
+uid_t geteuid(void);
+gid_t getgid(void);
+gid_t getegid(void);
+
 #endif /* _SYS_UNISTD_H */
diff --git a/components/libc/compilers/dlib/syscall_remove.c b/components/libc/compilers/dlib/syscall_remove.c
index e7f0268b1b..f7e64d1997 100644
--- a/components/libc/compilers/dlib/syscall_remove.c
+++ b/components/libc/compilers/dlib/syscall_remove.c
@@ -9,16 +9,16 @@
  */
 #include <rtthread.h>
 #ifdef RT_USING_DFS
-#include <dfs_file.h>
+#include <dfs_posix.h>
 #endif
 #include <yfuns.h>
 
 #pragma module_name = "?remove"
 int remove(const char *val)
 {
-#ifdef RT_USING_DFS
-    dfs_file_unlink(val);
+#ifndef RT_USING_DFS
+    return -1;
+#else
+    return unlink(val);
 #endif
-
-    return 0;
 }
diff --git a/components/libc/compilers/dlib/syscalls.c b/components/libc/compilers/dlib/syscalls.c
new file mode 100644
index 0000000000..007ea76bd1
--- /dev/null
+++ b/components/libc/compilers/dlib/syscalls.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-02-13     Meco Man     implement exit() and abort()
+ * 2021-02-20     Meco Man     add system()
+ */
+#include <rtthread.h>
+
+/* for exit() and abort() */
+void __exit (int status)
+{
+    extern void __rt_libc_exit(int status);
+    __rt_libc_exit(status);
+    while(1);
+}
+
+int system(const char * string)
+{
+    extern int __rt_libc_system(const char *string);
+    return __rt_libc_system(string);
+}
diff --git a/components/libc/compilers/dlib/syscalls.h b/components/libc/compilers/dlib/syscalls.h
deleted file mode 100644
index 993962e8db..0000000000
--- a/components/libc/compilers/dlib/syscalls.h
+++ /dev/null
@@ -1,10 +0,0 @@
-/*
- * Copyright (c) 2006-2018, RT-Thread Development Team
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Change Logs:
- * Date           Author       Notes
- * 2015-01-28     Bernard      first version
- */
-
diff --git a/components/libc/compilers/dlib/termios.h b/components/libc/compilers/dlib/termios.h
deleted file mode 100644
index 1956121225..0000000000
--- a/components/libc/compilers/dlib/termios.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/*
- * Copyright (c) 2006-2018, RT-Thread Development Team
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Change Logs:
- * Date           Author       Notes
- */
-#ifndef _TERMIOS_H__
-#define _TERMIOS_H__
-
-#include <sys/types.h>
-#include <posix_termios.h>
-
-#endif
diff --git a/components/libc/compilers/minilibc/SConscript b/components/libc/compilers/minilibc/SConscript
index 518d800571..dec657028f 100644
--- a/components/libc/compilers/minilibc/SConscript
+++ b/components/libc/compilers/minilibc/SConscript
@@ -8,7 +8,7 @@ group = []
 CPPPATH = [cwd]
 CPPDEFINES = ['RT_USING_MINILIBC']
 
-if rtconfig.PLATFORM == 'gcc' and rtconfig.ARCH != 'sim' and not GetDepend('RT_USING_LIBC'):
+if rtconfig.PLATFORM == 'gcc' and rtconfig.ARCH != 'sim' and not GetDepend('RT_USING_LIBC') and GetDepend('RT_USING_MINILIBC'):
     group = DefineGroup('libc', src, depend = [''],
         CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES)
 
diff --git a/components/libc/compilers/newlib/README.md b/components/libc/compilers/newlib/README.md
new file mode 100644
index 0000000000..385f329a4f
--- /dev/null
+++ b/components/libc/compilers/newlib/README.md
@@ -0,0 +1,9 @@
+# NEWLIB (GCC) porting for RT-Thread
+
+Please define RT_USING_LIBC and compile RT-Thread with GCC compiler.
+
+
+
+## More Information
+
+https://sourceware.org/newlib/libc.html#Reentrancy
\ No newline at end of file
diff --git a/components/libc/compilers/newlib/SConscript b/components/libc/compilers/newlib/SConscript
index 06e5faad09..d0868bbdea 100644
--- a/components/libc/compilers/newlib/SConscript
+++ b/components/libc/compilers/newlib/SConscript
@@ -15,7 +15,7 @@ CPPDEFINES = ['RT_USING_NEWLIB']
 LIBS = ['c', 'm']
 
 if rtconfig.PLATFORM == 'gcc':
-    group = DefineGroup('newlib', src, depend = ['RT_USING_LIBC'], 
+    group = DefineGroup('libc', src, depend = ['RT_USING_LIBC'], 
         CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES, LIBS = LIBS)
 
 Return('group')
diff --git a/components/libc/compilers/newlib/libc.h b/components/libc/compilers/newlib/libc.h
index fdf2ab4f60..9a76ffb79f 100644
--- a/components/libc/compilers/newlib/libc.h
+++ b/components/libc/compilers/newlib/libc.h
@@ -10,23 +10,10 @@
 #ifndef __RTT_LIBC_H__
 #define __RTT_LIBC_H__
 
-#include <stdio.h>
-#include <stdint.h>
-#include <string.h>
-#include <sys/time.h>
-
 #ifndef _EXFUN
-#define _EXFUN(name, proto)		name proto
+#define _EXFUN(name, proto)     name proto
 #endif
 
-#define MILLISECOND_PER_SECOND  1000UL
-#define MICROSECOND_PER_SECOND  1000000UL
-#define NANOSECOND_PER_SECOND   1000000000UL
-
-#define MILLISECOND_PER_TICK    (MILLISECOND_PER_SECOND / RT_TICK_PER_SECOND)
-#define MICROSECOND_PER_TICK    (MICROSECOND_PER_SECOND / RT_TICK_PER_SECOND)
-#define NANOSECOND_PER_TICK     (NANOSECOND_PER_SECOND  / RT_TICK_PER_SECOND)
-
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -34,10 +21,6 @@ int libc_system_init(void);
 int libc_stdio_set_console(const char* device_name, int mode);
 int libc_stdio_get_console(void);
 
-/* some time related function */
-int libc_set_time(const struct timespec* time);
-int libc_get_time(struct timespec* time);
-int libc_time_to_tick(const struct timespec* time);
 #ifdef __cplusplus
 }
 #endif
diff --git a/components/libc/compilers/newlib/libc_syms.c b/components/libc/compilers/newlib/libc_syms.c
index b150c10fd6..4b0ee355f0 100644
--- a/components/libc/compilers/newlib/libc_syms.c
+++ b/components/libc/compilers/newlib/libc_syms.c
@@ -39,10 +39,6 @@ RTM_EXPORT(snprintf);
 
 RTM_EXPORT(fwrite);
 
-#include <time.h>
-RTM_EXPORT(localtime);
-RTM_EXPORT(time);
-
 #include <setjmp.h>
 RTM_EXPORT(longjmp);
 RTM_EXPORT(setjmp);
diff --git a/components/libc/compilers/newlib/machine/time.h b/components/libc/compilers/newlib/machine/time.h
new file mode 100644
index 0000000000..d46533eb39
--- /dev/null
+++ b/components/libc/compilers/newlib/machine/time.h
@@ -0,0 +1,12 @@
+#ifndef _MACHTIME_H_
+#define _MACHTIME_H_
+
+#include <rtconfig.h>
+#define _CLOCKS_PER_SEC_   RT_TICK_PER_SECOND
+
+#ifdef __SPU__
+#include <sys/_timespec.h>
+int nanosleep (const struct timespec *, struct timespec *);
+#endif
+
+#endif	/* _MACHTIME_H_ */
diff --git a/components/libc/compilers/newlib/syscalls.c b/components/libc/compilers/newlib/syscalls.c
index 228fa0d140..949d8a61de 100644
--- a/components/libc/compilers/newlib/syscalls.c
+++ b/components/libc/compilers/newlib/syscalls.c
@@ -5,11 +5,16 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2021-02-11     Meco Man     remove _gettimeofday_r() and _times_r()
+ * 2020-02-13     Meco Man     re-implement exit() and abort()
+ * 2020-02-21     Meco Man     improve and beautify syscalls
+ * 2020-02-24     Meco Man     fix bug of _isatty_r()
  */
+
 #include <reent.h>
-#include <sys/errno.h>
-#include <sys/time.h>
+#include <errno.h>
 #include <stdio.h>
+#include <sys/time.h>
 
 #include <rtthread.h>
 
@@ -32,10 +37,18 @@ __errno ()
 #endif
 
 int
+_getpid_r(struct _reent *ptr)
+{
+    return 0;
+}
+
+int
 _close_r(struct _reent *ptr, int fd)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     return close(fd);
 #endif
@@ -74,21 +87,17 @@ _fstat_r(struct _reent *ptr, int fd, struct stat *pstat)
 }
 
 int
-_getpid_r(struct _reent *ptr)
-{
-    return 0;
-}
-
-int
 _isatty_r(struct _reent *ptr, int fd)
 {
-    if (fd >=0 && fd < 3) return 1;
-
-    /* return "not supported" */
-    ptr->_errno = ENOTSUP;
-    return -1;
+    if (fd >=0 && fd < 3)
+    {
+        return 1;
+    }
+    else
+    {
+        return 0;
+    }
 }
-
 int
 _kill_r(struct _reent *ptr, int pid, int sig)
 {
@@ -109,7 +118,9 @@ _off_t
 _lseek_r(struct _reent *ptr, int fd, _off_t pos, int whence)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     _off_t rc;
 
@@ -122,7 +133,9 @@ int
 _mkdir_r(struct _reent *ptr, const char *name, int mode)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     int rc;
 
@@ -135,7 +148,9 @@ int
 _open_r(struct _reent *ptr, const char *file, int flags, int mode)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     int rc;
 
@@ -148,7 +163,9 @@ _ssize_t
 _read_r(struct _reent *ptr, int fd, void *buf, size_t nbytes)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     _ssize_t rc;
 
@@ -161,7 +178,9 @@ int
 _rename_r(struct _reent *ptr, const char *old, const char *new)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     int rc;
 
@@ -181,7 +200,9 @@ int
 _stat_r(struct _reent *ptr, const char *file, struct stat *pstat)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
     int rc;
 
@@ -190,24 +211,15 @@ _stat_r(struct _reent *ptr, const char *file, struct stat *pstat)
 #endif
 }
 
-_CLOCK_T_
-_times_r(struct _reent *ptr, struct tms *ptms)
-{
-    /* return "not supported" */
-    ptr->_errno = ENOTSUP;
-    return -1;
-}
-
 int
 _unlink_r(struct _reent *ptr, const char *file)
 {
 #ifndef RT_USING_DFS
-    return 0;
+    /* return "not supported" */
+    ptr->_errno = ENOTSUP;
+    return -1;
 #else
-    int rc;
-
-    rc = unlink(file);
-    return rc;
+    return unlink(file);
 #endif
 }
 
@@ -219,11 +231,11 @@ _wait_r(struct _reent *ptr, int *status)
     return -1;
 }
 
-#ifdef RT_USING_DEVICE
 _ssize_t
 _write_r(struct _reent *ptr, int fd, const void *buf, size_t nbytes)
 {
 #ifndef RT_USING_DFS
+#ifdef RT_USING_DEVICE
     if (fileno(stdout) == fd)
     {
         rt_device_t console;
@@ -233,120 +245,18 @@ _write_r(struct _reent *ptr, int fd, const void *buf, size_t nbytes)
     }
 
     return 0;
-
 #else
-    _ssize_t rc;
-
-    rc = write(fd, buf, nbytes);
-    return rc;
-#endif
-}
-#endif
-
-#ifdef RT_USING_PTHREADS
-
-#include <clock_time.h>
-/* POSIX timer provides clock_gettime function */
-#include <time.h>
-int
-_gettimeofday_r(struct _reent *ptr, struct timeval *__tp, void *__tzp)
-{
-    struct timespec tp;
-
-    if (clock_gettime(CLOCK_REALTIME, &tp) == 0)
-    {
-        if (__tp != RT_NULL)
-        {
-            __tp->tv_sec  = tp.tv_sec;
-            __tp->tv_usec = tp.tv_nsec / 1000UL;
-        }
-
-        return tp.tv_sec;
-    }
-
     /* return "not supported" */
     ptr->_errno = ENOTSUP;
     return -1;
-}
-
+#endif /*RT_USING_DEVICE*/
 #else
+    _ssize_t rc;
 
-#define MILLISECOND_PER_SECOND  1000UL
-#define MICROSECOND_PER_SECOND  1000000UL
-#define NANOSECOND_PER_SECOND   1000000000UL
-
-#define MILLISECOND_PER_TICK    (MILLISECOND_PER_SECOND / RT_TICK_PER_SECOND)
-#define MICROSECOND_PER_TICK    (MICROSECOND_PER_SECOND / RT_TICK_PER_SECOND)
-#define NANOSECOND_PER_TICK     (NANOSECOND_PER_SECOND  / RT_TICK_PER_SECOND)
-
-struct timeval _timevalue = {0};
-#ifdef RT_USING_DEVICE
-static void libc_system_time_init(void)
-{
-    time_t time;
-    rt_tick_t tick;
-    rt_device_t device;
-
-    time = 0;
-    device = rt_device_find("rtc");
-    if (device != RT_NULL)
-    {
-        /* get realtime seconds */
-        rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
-    }
-
-    /* get tick */
-    tick = rt_tick_get();
-
-    _timevalue.tv_usec = MICROSECOND_PER_SECOND - (tick%RT_TICK_PER_SECOND) * MICROSECOND_PER_TICK;
-    _timevalue.tv_sec = time - tick/RT_TICK_PER_SECOND - 1;
-}
+    rc = write(fd, buf, nbytes);
+    return rc;
 #endif
-
-int libc_get_time(struct timespec *time)
-{
-    rt_tick_t tick;
-    static rt_bool_t inited = 0;
-
-    RT_ASSERT(time != RT_NULL);
-
-    /* initialize system time */
-    if (inited == 0)
-    {
-        libc_system_time_init();
-        inited = 1;
-    }
-
-    /* get tick */
-    tick = rt_tick_get();
-
-    time->tv_sec = _timevalue.tv_sec + tick / RT_TICK_PER_SECOND;
-    time->tv_nsec = (_timevalue.tv_usec + (tick % RT_TICK_PER_SECOND) * MICROSECOND_PER_TICK) * 1000;
-
-    return 0;
-}
-
-int
-_gettimeofday_r(struct _reent *ptr, struct timeval *__tp, void *__tzp)
-{
-    struct timespec tp;
-
-    if (libc_get_time(&tp) == 0)
-    {
-        if (__tp != RT_NULL)
-        {
-            __tp->tv_sec  = tp.tv_sec;
-            __tp->tv_usec = tp.tv_nsec / 1000UL;
-        }
-
-        return tp.tv_sec;
-    }
-
-    /* return "not supported" */
-    ptr->_errno = ENOTSUP;
-    return -1;
 }
-#endif
 
 /* Memory routine */
 void *
@@ -396,27 +306,20 @@ _free_r (struct _reent *ptr, void *addr)
     rt_free (addr);
 }
 
-void
-exit (int status)
+/* for exit() and abort() */
+__attribute__ ((noreturn)) void
+_exit (int status)
 {
-#ifdef RT_USING_MODULE
-    if (dlmodule_self())
-    {
-        dlmodule_exit(status);
-    }
-#endif
-
-    rt_kprintf("thread:%s exit with %d\n", rt_thread_self()->name, status);
-    RT_ASSERT(0);
-
-    while (1);
+    extern void __rt_libc_exit(int status);
+    __rt_libc_exit(status);
+    while(1);
 }
 
 void
 _system(const char *s)
 {
-    /* not support this call */
-    return;
+    extern int __rt_libc_system(const char *string);
+    __rt_libc_system(s);
 }
 
 void __libc_init_array(void)
@@ -424,26 +327,6 @@ void __libc_init_array(void)
     /* we not use __libc init_aray to initialize C++ objects */
 }
 
-void abort(void)
-{
-    if (rt_thread_self())
-    {
-        rt_thread_t self = rt_thread_self();
-
-        rt_kprintf("thread:%-8.*s abort!\n", RT_NAME_MAX, self->name);
-        rt_thread_suspend(self);
-
-        rt_schedule();
-    }
-
-    while (1);
-}
-
-uid_t getuid(void)
-{
-    return 0;
-}
-
 mode_t umask(mode_t mask)
 {
     return 022;
@@ -453,3 +336,9 @@ int flock(int fd, int operation)
 {
     return 0;
 }
+
+/*
+These functions are implemented and replaced by the 'common/time.c' file
+int _gettimeofday_r(struct _reent *ptr, struct timeval *__tp, void *__tzp);
+_CLOCK_T_  _times_r(struct _reent *ptr, struct tms *ptms);
+*/
diff --git a/components/libc/compilers/newlib/time.c b/components/libc/compilers/newlib/time.c
deleted file mode 100644
index f099d51330..0000000000
--- a/components/libc/compilers/newlib/time.c
+++ /dev/null
@@ -1,82 +0,0 @@
-/*
- * Copyright (c) 2006-2018, RT-Thread Development Team
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Change Logs:
- * Date           Author       Notes
- */
-#include <sys/time.h>
-#include <rtthread.h>
-
-#ifdef RT_USING_DEVICE
-int gettimeofday(struct timeval *tp, void *ignore)
-{
-    time_t time;
-    rt_device_t device;
-
-    device = rt_device_find("rtc");
-    RT_ASSERT(device != RT_NULL);
-
-    rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
-    if (tp != RT_NULL)
-    {
-        tp->tv_sec = time;
-        tp->tv_usec = 0;
-    }
-
-    return time;
-}
-#endif
-
-/**
- * Returns the current time.
- *
- * @param time_t * t the timestamp pointer, if not used, keep NULL.
- *
- * @return time_t return timestamp current.
- *
- */
-/* for IAR 6.2 later Compiler */
-#if defined (__IAR_SYSTEMS_ICC__) &&  (__VER__) >= 6020000
-#pragma module_name = "?time"
-time_t (__time32)(time_t *t) /* Only supports 32-bit timestamp */
-#else
-time_t time(time_t *t)
-#endif
-{
-    time_t time_now = 0;
-
-#ifdef RT_USING_RTC
-    static rt_device_t device = RT_NULL;
-
-    /* optimization: find rtc device only first. */
-    if (device == RT_NULL)
-    {
-        device = rt_device_find("rtc");
-    }
-
-    /* read timestamp from RTC device. */
-    if (device != RT_NULL)
-    {
-        if (rt_device_open(device, 0) == RT_EOK)
-        {
-            rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time_now);
-            rt_device_close(device);
-        }
-    }
-#endif /* RT_USING_RTC */
-
-    /* if t is not NULL, write timestamp to *t */
-    if (t != RT_NULL)
-    {
-        *t = time_now;
-    }
-
-    return time_now;
-}
-
-RT_WEAK clock_t clock(void)
-{
-    return rt_tick_get();
-}