/*-------------------------------------------------------------------------
 * drawElements Thread Library
 * ---------------------------
 *
 * Copyright 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *//*!
 * \file
 * \brief Unix implementation of mutex.
 *//*--------------------------------------------------------------------*/

#include "deMutex.h"

#if (DE_OS == DE_OS_UNIX || DE_OS == DE_OS_ANDROID || DE_OS == DE_OS_SYMBIAN || DE_OS == DE_OS_QNX || DE_OS == DE_OS_OSX || DE_OS == DE_OS_IOS)

#include "deMemory.h"

#include <pthread.h>

/* \todo [2009-11-12 pyry] It is quite nasty to allocate mutex structs from heap. */

DE_STATIC_ASSERT(sizeof(deMutex) >= sizeof(pthread_mutex_t*));

deMutex deMutex_create (const deMutexAttributes* attributes)
{
	pthread_mutexattr_t	attr;
	int					ret;
	pthread_mutex_t*	mutex = deMalloc(sizeof(pthread_mutex_t));

	if (!mutex)
		return 0;

	if (pthread_mutexattr_init(&attr) != 0)
	{
		deFree(mutex);
		return 0;
	}

#if defined(DE_DEBUG)
	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK) != 0)
#else
	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL) != 0)
#endif
	{
		pthread_mutexattr_destroy(&attr);
		deFree(mutex);
		return 0;
	}

	if (attributes)
	{
		if (attributes->flags & DE_MUTEX_RECURSIVE)
		{
			if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) != 0)
			{
				pthread_mutexattr_destroy(&attr);
				deFree(mutex);
				return 0;
			}
		}
	}

	ret = pthread_mutex_init(mutex, &attr);
	if (ret != 0)
	{
		pthread_mutexattr_destroy(&attr);
		deFree(mutex);
		return 0;
	}

	pthread_mutexattr_destroy(&attr);

	return (deMutex)mutex;
}

void deMutex_destroy (deMutex mutex)
{
	pthread_mutex_t* pMutex = (pthread_mutex_t*)mutex;
	DE_ASSERT(pMutex);
	pthread_mutex_destroy(pMutex);
	deFree(pMutex);
}

void deMutex_lock (deMutex mutex)
{
	int ret = pthread_mutex_lock((pthread_mutex_t*)mutex);
	DE_ASSERT(ret == 0);
	DE_UNREF(ret);
}

void deMutex_unlock (deMutex mutex)
{
	int ret = pthread_mutex_unlock((pthread_mutex_t*)mutex);
	DE_ASSERT(ret == 0);
	DE_UNREF(ret);
}

deBool deMutex_tryLock (deMutex mutex)
{
	return (pthread_mutex_trylock((pthread_mutex_t*)mutex) == 0);
}

#endif /* DE_OS */