Function clock_gettime

kernel/cellos/src/sys_time.cpp:87–116

static u64 mt_timestart = 0;

static int clock_gettime(int clk_id, struct timespec *tp) {
  kern_return_t retval = KERN_SUCCESS;
  if (clk_id == TIMER_ABSTIME) {
    if (!mt_timestart) {
      // only one timer, initilized on the first call to the TIMER
      mach_timebase_info_data_t tb = {0};
      mach_timebase_info(&tb);
      mt_timebase = tb.numer;
      mt_timebase /= tb.denom;
      mt_timestart = mach_absolute_time();
    }

    double diff = (mach_absolute_time() - mt_timestart) * mt_timebase;
    tp->tv_sec = diff * MT_NANO;
    tp->tv_nsec = diff - (tp->tv_sec * MT_GIGA);
  } else // other clk_ids are mapped to the coresponding mach clock_service
  {
    clock_serv_t cclock;
    mach_timespec_t mts;

    host_get_clock_service(mach_host_self(), clk_id, &cclock);
    retval = clock_get_time(cclock, &mts);
    mach_port_deallocate(mach_task_self(), cclock);

    tp->tv_sec = mts.tv_sec;
    tp->tv_nsec = mts.tv_nsec;
  }

  return retval;
}
#endif

#endif