glibc/nptl/pthread_rwlock_trywrlock.c

44 lines
1.4 KiB
C

/* Copyright (C) 2002 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include "pthreadP.h"
#include <lowlevellock.h>
int
__pthread_rwlock_trywrlock (rwlock)
pthread_rwlock_t *rwlock;
{
int result = EBUSY;
lll_mutex_lock (rwlock->__data.__lock);
if (rwlock->__data.__writer == 0 && rwlock->__data.__nr_readers == 0)
{
rwlock->__data.__writer = (pthread_t) THREAD_SELF;
result = 0;
}
lll_mutex_unlock (rwlock->__data.__lock);
return result;
}
strong_alias (__pthread_rwlock_trywrlock, pthread_rwlock_trywrlock)