/*
 * Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version 3.0 only,
 * as published by the Free Software Foundation.
 *
 * This program 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
 * version 3.0 for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3.0 along with this program. If not, see
 * <https://www.gnu.org/licenses/>.
 */

#include "config.h"

#import "OFPlainMutex.h"

int
OFPlainMutexNew(OFPlainMutex *mutex)
{
	return pthread_mutex_init(mutex, NULL);
}

int
OFPlainMutexLock(OFPlainMutex *mutex)
{
	return pthread_mutex_lock(mutex);
}

int
OFPlainMutexTryLock(OFPlainMutex *mutex)
{
	return pthread_mutex_trylock(mutex);
}

int
OFPlainMutexUnlock(OFPlainMutex *mutex)
{
	return pthread_mutex_unlock(mutex);
}

int
OFPlainMutexFree(OFPlainMutex *mutex)
{
	return pthread_mutex_destroy(mutex);
}

#ifdef OF_HAVE_RECURSIVE_PTHREAD_MUTEXES
int
OFPlainRecursiveMutexNew(OFPlainRecursiveMutex *rmutex)
{
	int error;
	pthread_mutexattr_t attr;

	if ((error = pthread_mutexattr_init(&attr)) != 0)
		return error;

	if ((error = pthread_mutexattr_settype(&attr,
	    PTHREAD_MUTEX_RECURSIVE)) != 0)
		return error;

	if ((error = pthread_mutex_init(rmutex, &attr)) != 0)
		return error;

	if ((error = pthread_mutexattr_destroy(&attr)) != 0)
		return error;

	return 0;
}

int
OFPlainRecursiveMutexLock(OFPlainRecursiveMutex *rmutex)
{
	return OFPlainMutexLock(rmutex);
}

int
OFPlainRecursiveMutexTryLock(OFPlainRecursiveMutex *rmutex)
{
	return OFPlainMutexTryLock(rmutex);
}

int
OFPlainRecursiveMutexUnlock(OFPlainRecursiveMutex *rmutex)
{
	return OFPlainMutexUnlock(rmutex);
}

int
OFPlainRecursiveMutexFree(OFPlainRecursiveMutex *rmutex)
{
	return OFPlainMutexFree(rmutex);
}
#else
int
OFPlainRecursiveMutexNew(OFPlainRecursiveMutex *rmutex)
{
	int error;

	if ((error = OFPlainMutexNew(&rmutex->mutex)) != 0)
		return error;

	if ((error = OFTLSKeyNew(&rmutex->count)) != 0)
		return error;

	return 0;
}

int
OFPlainRecursiveMutexLock(OFPlainRecursiveMutex *rmutex)
{
	uintptr_t count = (uintptr_t)OFTLSKeyGet(rmutex->count);
	int error;

	if (count > 0) {
		if ((error = OFTLSKeySet(rmutex->count,
		    (void *)(count + 1))) != 0)
			return error;

		return 0;
	}

	if ((error = OFPlainMutexLock(&rmutex->mutex)) != 0)
		return error;

	if ((error = OFTLSKeySet(rmutex->count, (void *)1)) != 0) {
		OFPlainMutexUnlock(&rmutex->mutex);
		return error;
	}

	return 0;
}

int
OFPlainRecursiveMutexTryLock(OFPlainRecursiveMutex *rmutex)
{
	uintptr_t count = (uintptr_t)OFTLSKeyGet(rmutex->count);
	int error;

	if (count > 0) {
		if ((error = OFTLSKeySet(rmutex->count,
		    (void *)(count + 1))) != 0)
			return error;

		return 0;
	}

	if ((error = OFPlainMutexTryLock(&rmutex->mutex)) != 0)
		return error;

	if ((error = OFTLSKeySet(rmutex->count, (void *)1)) != 0) {
		OFPlainMutexUnlock(&rmutex->mutex);
		return error;
	}

	return 0;
}

int
OFPlainRecursiveMutexUnlock(OFPlainRecursiveMutex *rmutex)
{
	uintptr_t count = (uintptr_t)OFTLSKeyGet(rmutex->count);
	int error;

	if (count > 1) {
		if ((error = OFTLSKeySet(rmutex->count,
		    (void *)(count - 1))) != 0)
			return error;

		return 0;
	}

	if ((error = OFTLSKeySet(rmutex->count, (void *)0)) != 0)
		return error;

	if ((error = OFPlainMutexUnlock(&rmutex->mutex)) != 0)
		return error;

	return 0;
}

int
OFPlainRecursiveMutexFree(OFPlainRecursiveMutex *rmutex)
{
	int error;

	if ((error = OFPlainMutexFree(&rmutex->mutex)) != 0)
		return error;

	if ((error = OFTLSKeyFree(rmutex->count)) != 0)
		return error;

	return 0;
}
#endif