// thread/kaldi-mutex.h

// Copyright 2012 Karel Vesely (Brno University of Technology)

// See ../../COPYING for clarification regarding multiple authors

//

// 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

//

// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED

// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,

// MERCHANTABLITY OR NON-INFRINGEMENT.

// See the Apache 2 License for the specific language governing permissions and

// limitations under the License.

#ifndef KALDI_THREAD_KALDI_MUTEX_H_

#define KALDI_THREAD_KALDI_MUTEX_H_ 1

#include <pthread.h>

namespace kaldi {

/**

* This class encapsulates mutex to ensure

* exclusive access to some critical section

* which manipulates shared resources.

*

* Note.: The mutex MUST BE UNLOCKED from

* the SAME THREAD which has locked it!

*/

class Mutex {

public:

Mutex();

~Mutex();

void Lock();

/**

* Try to lock the mutex without waiting for it.

* Returns: true when lock successfull,

* false when mutex was already locked

*/

bool TryLock();

void Unlock();

private:

pthread_mutex_t mutex_;

KALDI_DISALLOW_COPY_AND_ASSIGN(Mutex);

};

} // namespace kaldi

#endif // KALDI_THREAD_KALDI_MUTEX_H_