gettimeofday.c

#include < time.h >
#include <windows.h> //I've ommited this line.
#if defined(_MSC_VER) || defined(_MSC_EXTENSIONS)
  #define DELTA_EPOCH_IN_MICROSECS  11644473600000000Ui64
#else
  #define DELTA_EPOCH_IN_MICROSECS  11644473600000000ULL
#endif

struct timezone
{
  int  tz_minuteswest; /* minutes W of Greenwich */
  int  tz_dsttime;     /* type of dst correction */
};

int gettimeofday(struct timeval *tv, struct timezone *tz)
{
  FILETIME ft;
  unsigned __int64 tmpres = 0;
  static int tzflag;

  if (NULL != tv)
  {
    GetSystemTimeAsFileTime(&ft);

    tmpres |= ft.dwHighDateTime;
    tmpres <<= 32;
    tmpres |= ft.dwLowDateTime;

    /*converting file time to unix epoch*/
    tmpres /= 10;  /*convert into microseconds*/
    tmpres -= DELTA_EPOCH_IN_MICROSECS;
    tv->tv_sec = (long)(tmpres / 1000000UL);
    tv->tv_usec = (long)(tmpres % 1000000UL);
  }

  if (NULL != tz)
  {
    if (!tzflag)
    {
      _tzset();
      tzflag++;
    }
    tz->tz_minuteswest = _timezone / 60;
    tz->tz_dsttime = _daylight;
  }

  return 0;
}

void usleep(__int64 waitTime)
{
    if (waitTime > 0)
    {
        if (waitTime > 100)
        {
            // use a waitable timer for larger intervals > 0.1ms

            HANDLE timer;
            LARGE_INTEGER ft;

            ft.QuadPart = -(10*waitTime); // Convert to 100 nanosecond interval, negative value indicates relative time

            timer = CreateWaitableTimer(NULL, TRUE, NULL);
            SetWaitableTimer(timer, &ft, 0, NULL, NULL, 0);
            WaitForSingleObject(timer, INFINITE);
            CloseHandle(timer);
        }
        else
        {
            // use a polling loop for short intervals <= 100ms

            LARGE_INTEGER perfCnt, start, now;
            __int64 elapsed;

            QueryPerformanceFrequency(&perfCnt);
            QueryPerformanceCounter(&start);
            do {
                QueryPerformanceCounter((LARGE_INTEGER*) &now);
                elapsed = (__int64)((now.QuadPart - start.QuadPart) / (float)perfCnt.QuadPart * 1000 * 1000);
            } while ( elapsed < waitTime );
        }
    }
}