compat/timespec_get.c

   1 /*****************************************************************************
   2  * timespec_get.c: C11 timespec_get() replacement
   3  *****************************************************************************
   4  * Copyright © 2015 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #ifdef _WIN32
  26 #include <windows.h>
  27
  28 int timespec_get(struct timespec *ts, int base)
  29 {
  30     FILETIME ft;
  31     ULARGE_INTEGER s;
  32     ULONGLONG t;
  33
  34     if (base != TIME_UTC)
  35         return 0;
  36
  37     GetSystemTimeAsFileTime(&ft);
  38     s.LowPart = ft.dwLowDateTime;
  39     s.HighPart = ft.dwHighDateTime;
  40     t = s.QuadPart - 116444736000000000ULL;
  41     ts->tv_sec = t / 10000000;
  42     ts->tv_nsec = ((int) (t % 10000000)) * 100;
  43     return base;
  44 }
  45 #else /* !_WIN32 */
  46
  47 #include <time.h>
  48 #include <unistd.h> /* _POSIX_TIMERS */
  49 #ifndef _POSIX_TIMERS
  50 #define _POSIX_TIMERS (-1)
  51 #endif
  52 #if (_POSIX_TIMERS <= 0)
  53 # include <sys/time.h> /* gettimeofday() */
  54 #endif
  55
  56 int timespec_get(struct timespec *ts, int base)
  57 {
  58     switch (base)
  59     {
  60         case TIME_UTC:
  61 #if (_POSIX_TIMERS >= 0)
  62             if (clock_gettime(CLOCK_REALTIME, ts) == 0)
  63                 break;
  64 #endif
  65 #if (_POSIX_TIMERS <= 0)
  66         {
  67             struct timeval tv;
  68
  69             if (gettimeofday(&tv, NULL) == 0)
  70             {
  71                 ts->tv_sec = tv.tv_sec;
  72                 ts->tv_nsec = tv.tv_usec * 1000;
  73                 break;
  74             }
  75         }
  76 #endif
  77             /* fall through */
  78         default:
  79             return 0;
  80     }
  81     return base;
  82 }
  83 #endif /* !_WIN32 */