RWMutex.cpp

Go to the documentation of this file.

/*
 * RWMutex.cpp
 *
 * Copyright (C) 2011 IBR, TU Braunschweig
 *
 * Written-by: Johannes Morgenroth <morgenroth@ibr.cs.tu-bs.de>
 *
 * 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.
 *
 */

#include "ibrcommon/thread/RWMutex.h"
#include <errno.h>

namespace ibrcommon
{
        RWMutex::RWMutex()
        {
                pthread_rwlock_init(&_rwlock, NULL);
        }

        RWMutex::~RWMutex()
        {
                pthread_rwlock_destroy(&_rwlock);
        }

        void RWMutex::trylock(LockState state) throw (MutexException)
        {
                int ret = 0;

                switch (state) {
                case LOCK_READONLY:
                        ret = pthread_rwlock_tryrdlock(&_rwlock);
                        break;

                case LOCK_READWRITE:
                        ret = pthread_rwlock_trywrlock(&_rwlock);
                        break;
                }

                switch (ret)
                {
                case 0:
                        break;

                case EBUSY:
                        throw MutexException("The mutex could not be acquired because it was already locked.");
                        break;
                }
        }

        void RWMutex::enter(LockState state) throw (MutexException)
        {
                switch (state) {
                case LOCK_READONLY:
                        pthread_rwlock_rdlock(&_rwlock);
                        break;

                case LOCK_READWRITE:
                        pthread_rwlock_wrlock(&_rwlock);
                        break;
                }
        }

        void RWMutex::leave() throw (MutexException)
        {
                pthread_rwlock_unlock(&_rwlock);
        }
} /* namespace ibrcommon */