C++ (Cpp) INT_SUBTRACT_OVERFLOW Beispiele

Beispiel #1

Datei: timespec-sub.c Projekt: JamesWatling/emacs-mac-port

struct timespec
timespec_sub (struct timespec a, struct timespec b)
{
  struct timespec r;
  time_t rs = a.tv_sec;
  time_t bs = b.tv_sec;
  int ns = a.tv_nsec - b.tv_nsec;
  int rns = ns;

  if (ns < 0)
    {
      rns = ns + 1000000000;
      if (rs == TYPE_MINIMUM (time_t))
        {
          if (bs <= 0)
            goto low_overflow;
          bs--;
        }
      else
        rs--;
    }

  if (INT_SUBTRACT_OVERFLOW (rs, bs))
    {
      if (rs < 0)
        {
        low_overflow:
          rs = TYPE_MINIMUM (time_t);
          rns = 0;
        }
      else
        {
          rs = TYPE_MAXIMUM (time_t);
          rns = 999999999;
        }
    }
  else
    rs -= bs;

  r.tv_sec = rs;
  r.tv_nsec = rns;
  return r;
}

Beispiel #2

Datei: timespec-sub.c Projekt: NeoTse/deepin-emacs

struct timespec
timespec_sub (struct timespec a, struct timespec b)
{
  time_t rs = a.tv_sec;
  time_t bs = b.tv_sec;
  int ns = a.tv_nsec - b.tv_nsec;
  int rns = ns;

  if (ns < 0)
    {
      rns = ns + TIMESPEC_RESOLUTION;
      if (rs == TYPE_MINIMUM (time_t))
        {
          if (bs <= 0)
            goto low_overflow;
          bs--;
        }
      else
        rs--;
    }

  if (INT_SUBTRACT_OVERFLOW (rs, bs))
    {
      if (rs < 0)
        {
        low_overflow:
          rs = TYPE_MINIMUM (time_t);
          rns = 0;
        }
      else
        {
          rs = TYPE_MAXIMUM (time_t);
          rns = TIMESPEC_RESOLUTION - 1;
        }
    }
  else
    rs -= bs;

  return make_timespec (rs, rns);
}