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/* Copyright (C) 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <sysdep.h>
#include <lowlevellock.h>
#include <internaltypes.h>
#include <shlib-compat.h>
int
sem_timedwait (sem, abstime)
sem_t *sem;
const struct timespec *abstime;
{
int oldval, val;
val = *(int *) sem;
do
{
while (__builtin_expect (val == 0, 0))
{
/* Check for invalid timeout values. */
if (abstime->tv_nsec >= 1000000000)
{
__set_errno (EINVAL);
return -1;
}
/* Get the current time. */
struct timeval tv;
(void) gettimeofday(&tv, NULL);
/* Compute the relative timeout. */
struct timespec rt;
rt.tv_sec = abstime->tv_sec - tv.tv_sec;
rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000;
if (rt.tv_nsec < 0)
{
rt.tv_nsec += 1000000000;
--rt.tv_sec;
}
/* Already timed out. */
if (rt.tv_sec < 0)
{
__set_errno (ETIMEDOUT);
return -1;
}
/* Do wait. */
int err = lll_futex_timed_wait ((int *) sem, 0, &rt);
/* Returned after timing out? */
if (err == -ETIMEDOUT)
{
__set_errno (ETIMEDOUT);
return -1;
}
/* Handle EINTR. */
if (err != 0 && err != -EWOULDBLOCK)
{
__set_errno (-err);
return -1;
}
val = *(int *) sem;
}
oldval = val;
}
while ((val = lll_compare_and_swap ((int *) sem, oldval, oldval - 1))
!= oldval);
return 0;
}
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