compat/gettimeofday.c

   1 /*****************************************************************************
   2  * gettimeofday.c: gettimeofday() replacement
   3  *****************************************************************************
   4  * Copyright © 2014 VLC authors and VideoLAN
   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 <winsock2.h>
  27
  28 /* FILETIME of Jan 1 1970 00:00:00. */
  29 static const unsigned __int64 epoch = 116444736000000000;
  30
  31 /*
  32  * timezone information is stored outside the kernel so tzp isn't used anymore.
  33  *
  34  * Note: this function is not for Win32 high precision timing purpose. See
  35  * elapsed_time().
  36  */
  37 int gettimeofday(struct timeval * tp, struct timezone * tzp)
  38 {
  39     (void)tzp;
  40     FILETIME       file_time;
  41     SYSTEMTIME     system_time;
  42     ULARGE_INTEGER ularge;
  43
  44     GetSystemTime(&system_time);
  45     SystemTimeToFileTime(&system_time, &file_time);
  46     ularge.LowPart  = file_time.dwLowDateTime;
  47     ularge.HighPart = file_time.dwHighDateTime;
  48
  49     tp->tv_sec  = (long) ((ularge.QuadPart - epoch) / 10000000L);
  50     tp->tv_usec = (long) (system_time.wMilliseconds * 1000);
  51
  52     return 0;
  53 }
  54 #endif /* _WIN32 */