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/**
* Copyright (c) 2013, Ford Motor Company
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the
* distribution.
*
* Neither the name of the Ford Motor Company nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "utils/lock.h"
#include <errno.h>
#include "utils/logger.h"
namespace {
log4cxx::LoggerPtr g_logger =
log4cxx::LoggerPtr(log4cxx::Logger::getLogger("Utils"));
}
namespace sync_primitives {
Lock::Lock()
#ifndef NDEBUG
: lock_taken_(false)
#endif // NDEBUG
{
int32_t status = pthread_mutex_init(&mutex_, NULL);
if (status != 0) {
LOG4CXX_ERROR(g_logger, "Failed to initialize mutex");
}
}
Lock::~Lock() {
#ifndef NDEBUG
if (lock_taken_) {
LOG4CXX_ERROR(g_logger, "Destroying non-released mutex");
}
#endif
int32_t status = pthread_mutex_destroy(&mutex_);
if (status != 0) {
LOG4CXX_ERROR(g_logger, "Failed to destroy mutex");
}
}
void Lock::Ackquire() {
int32_t status = pthread_mutex_lock(&mutex_);
if (status != 0) {
LOG4CXX_ERROR(g_logger, "Failed to acquire mutex");
}
AssertFreeAndMarkTaken();
}
void Lock::Release() {
AssertTakenAndMarkFree();
int32_t status = pthread_mutex_unlock(&mutex_);
if (status != 0) {
LOG4CXX_ERROR(g_logger, "Failed to unlock mutex");
}
}
bool Lock::Try() {
bool ackquired = false;
#ifndef NDEBUG
if (lock_taken_) {
LOG4CXX_ERROR(g_logger, "Trying to lock already taken mutex");
}
#endif
switch(pthread_mutex_trylock(&mutex_)) {
case 0: {
ackquired = true;
#ifndef NDEBUG
lock_taken_ = true;
#endif
} break;
case EBUSY: {
ackquired = false;
} break;
default: {
ackquired = false;
LOG4CXX_ERROR(g_logger, "Failed to try lock the mutex");
}
}
return ackquired;
}
#ifndef NDEBUG
void Lock::AssertFreeAndMarkTaken() {
if (lock_taken_) {
LOG4CXX_ERROR(g_logger, "Locking already taken mutex");
}
lock_taken_ = true;
}
void Lock::AssertTakenAndMarkFree() {
if (!lock_taken_) {
LOG4CXX_ERROR(g_logger, "Unlocking a mutex that is not taken");
}
lock_taken_ = false;
}
#endif
} // namespace sync_primitives
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