sortix--sortix/libc/pthread/pthread_mutex_unlock.c

/*
 * Copyright (c) 2013, 2014 Jonas 'Sortie' Termansen.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * pthread/pthread_mutex_unlock.c
 * Unlocks a mutex.
 */

#include <pthread.h>

static const unsigned long UNLOCKED_VALUE = 0;
static const unsigned long LOCKED_VALUE = 1;

int pthread_mutex_unlock(pthread_mutex_t* mutex)
{
	if ( mutex->type == PTHREAD_MUTEX_RECURSIVE && mutex->recursion )
		return mutex->recursion--, 0;
	mutex->owner = 0;
	mutex->lock = UNLOCKED_VALUE;
	return 0;
}