mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
04277e02d7
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
42 lines
1.2 KiB
C
42 lines
1.2 KiB
C
/* Lock a semaphore if it does not require blocking. Generic version.
|
|
Copyright (C) 2005-2019 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 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, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <semaphore.h>
|
|
#include <errno.h>
|
|
|
|
#include <pt-internal.h>
|
|
|
|
int
|
|
__sem_trywait (sem_t *sem)
|
|
{
|
|
__pthread_spin_lock (&sem->__lock);
|
|
if (sem->__value > 0)
|
|
/* Successful down. */
|
|
{
|
|
sem->__value--;
|
|
__pthread_spin_unlock (&sem->__lock);
|
|
return 0;
|
|
}
|
|
__pthread_spin_unlock (&sem->__lock);
|
|
|
|
errno = EAGAIN;
|
|
return -1;
|
|
}
|
|
|
|
strong_alias (__sem_trywait, sem_trywait);
|