glibc/nptl/pthread_rwlock_trywrlock.c

42 lines
1.4 KiB
C

/* Copyright (C) 2002-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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 <errno.h>
#include "pthreadP.h"
#include <lowlevellock.h>
int
__pthread_rwlock_trywrlock (pthread_rwlock_t *rwlock)
{
int result = EBUSY;
lll_lock (rwlock->__data.__lock, rwlock->__data.__shared);
if (rwlock->__data.__writer == 0 && rwlock->__data.__nr_readers == 0)
{
rwlock->__data.__writer = THREAD_GETMEM (THREAD_SELF, tid);
result = 0;
}
lll_unlock (rwlock->__data.__lock, rwlock->__data.__shared);
return result;
}
strong_alias (__pthread_rwlock_trywrlock, pthread_rwlock_trywrlock)