Cygwin: timers: clock_setres: make no-op

clock_setres is a questionable function only existing on QNX.
Disable the function, just return success for CLOCK_REALTIME
to maintain backward compatibility.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen 2018-11-27 13:59:37 +01:00
parent 0b868df147
commit 6df301076a
1 changed files with 2 additions and 36 deletions

View File

@ -688,47 +688,13 @@ clock_getres (clockid_t clk_id, struct timespec *tp)
extern "C" int
clock_setres (clockid_t clk_id, struct timespec *tp)
{
static NO_COPY bool period_set;
int status;
/* Don't use this function. It only exists in QNX. Just return
success on CLOCK_REALTIME for backward compat. */
if (clk_id != CLOCK_REALTIME)
{
set_errno (EINVAL);
return -1;
}
/* Convert to 100ns to match OS resolution. The OS uses ULONG values
to express resolution in 100ns units, so the coarsest timer resolution
is < 430 secs. Actually the coarsest timer resolution is only slightly
beyond 15ms, but this might change in future OS versions, so we play nice
here. */
ULONGLONG period = tp->tv_sec * NS100PERSEC
+ (tp->tv_nsec + (NSPERSEC/NS100PERSEC) - 1)
/ (NSPERSEC/NS100PERSEC);
/* clock_setres is non-POSIX/non-Linux. On QNX, the function always
rounds the incoming value to the nearest supported value. */
ULONG coarsest, finest, actual;
if (NT_SUCCESS (NtQueryTimerResolution (&coarsest, &finest, &actual)))
{
if (period > coarsest)
period = coarsest;
else if (finest > period)
period = finest;
}
if (period_set
&& NT_SUCCESS (NtSetTimerResolution (minperiod, FALSE, &actual)))
period_set = false;
status = NtSetTimerResolution (period, TRUE, &actual);
if (!NT_SUCCESS (status))
{
__seterrno_from_nt_status (status);
return -1;
}
minperiod = period;
period_set = true;
return 0;
}