mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-27 15:30:07 +00:00
82 lines
2.5 KiB
C
82 lines
2.5 KiB
C
/* High-resolution sleep with the specified clock.
|
|
Copyright (C) 2000 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
|
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <sys/time.h>
|
|
|
|
|
|
#ifndef CLOCK_P
|
|
# define CLOCK_P(clock) 0
|
|
#endif
|
|
|
|
|
|
/* This implementation assumes that these is only a `nanosleep' system
|
|
call. So we have to remap all other activities. */
|
|
int
|
|
clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
|
|
struct timespec *rem)
|
|
{
|
|
struct timespec now;
|
|
|
|
if (__builtin_expect (req->tv_nsec, 0) < 0
|
|
|| __builtin_expect (req->tv_nsec, 0) >= 1000000000)
|
|
return EINVAL;
|
|
|
|
/* If we got an absolute time, remap it. */
|
|
if (flags == TIMER_ABSTIME)
|
|
{
|
|
long int nsec;
|
|
long int sec;
|
|
|
|
/* Make sure we use safe data types. */
|
|
assert (sizeof (sec) >= sizeof (now.tv_sec));
|
|
|
|
/* Get the current time for this clock. */
|
|
if (__builtin_expect (clock_gettime (clock_id, &now), 0) != 0)
|
|
return errno;
|
|
|
|
/* Compute the difference. */
|
|
nsec = req->tv_nsec - now.tv_nsec;
|
|
sec = req->tv_sec - now.tv_sec - (nsec < 0);
|
|
if (sec < 0)
|
|
/* The time has already elapsed. */
|
|
return 0;
|
|
|
|
now.tv_sec = sec;
|
|
now.tv_nsec = nsec + (nsec < 0 ? 1000000000 : 0);
|
|
|
|
/* From now on this is our time. */
|
|
req = &now;
|
|
|
|
/* Make sure we are not modifying the struct pointed to by REM. */
|
|
rem = NULL;
|
|
}
|
|
else if (__builtin_expect (flags, 0) != 0)
|
|
return EINVAL;
|
|
else if (clock_id != CLOCK_REALTIME)
|
|
{
|
|
/* Make sure the clock ID is correct. */
|
|
if (__builtin_expect (! CLOCK_P (clock_id), 0))
|
|
return EINVAL;
|
|
}
|
|
|
|
return __builtin_expect (nanosleep (req, rem), 0) ? errno : 0;
|
|
}
|