pthread_iface.H

/* 
 * Copyright (c) 2005-2011, Guillaume Gimenez <guillaume@blackmilk.fr>
 * 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 G.Gimenez 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 G.GIMENEZ 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.
 *
 * Authors:
 *     * Guillaume Gimenez <guillaume@blackmilk.fr>
 *
 */
#ifndef __PTHREAD_IFACE_H__
#define __PTHREAD_IFACE_H__

#include <pthread.h>
#include "Object.H"


namespace raii {

	/*! The Mutual exclusion class.
	 * \sa raii::Lock
	 */
	class Mutex : public raii::Object {
		mutable pthread_mutex_t lock_;
		public:
		typedef enum {
			fastmutex=PTHREAD_MUTEX_NORMAL,
			recmutex=PTHREAD_MUTEX_RECURSIVE,
			errchkmutex=PTHREAD_MUTEX_ERRORCHECK
		} mutexType;

		/*! Create a new %Mutex
		 * \param t is the mutex type to create, default is fast mutex (which is a normal mutex)
		 *
		 */
		Mutex(mutexType t=fastmutex) : Object() {

			pthread_mutexattr_t attr;
			pthread_mutexattr_init(&attr);
			pthread_mutexattr_settype(&attr,t);

			pthread_mutex_init(&lock_,&attr);

			pthread_mutexattr_destroy(&attr);

		}

		/*! Destroy the mutex, weither it is locked or not
		 */
		~Mutex() {
			pthread_mutex_destroy(&lock_);
		}

		/*! lock this mutex
		 * \note the better is to use raii::Lock which follows RAII pattern
		 */
		void lock() const {
			pthread_mutex_lock(&lock_);
		}

		/*! unlock this mutex
		 * \note the better is to use raii::Lock which follows RAII pattern
		 */
		void unlock() const {
			pthread_mutex_unlock(&lock_);
		}
	};

	/*! %Lock is the object that manipulate Mutex for you.
	 * It uses RAII pattern to do the job.
	 * \code
	 * Mutex criticalSection;
	 * [...]
	 * {//enter critical section
	 *     Lock l1(criticalSection);
	 *     //here the critical things to do
	 * }//leave critical section
	 * \endcode
	 */
	class Lock : public raii::Object {
		const Mutex& mutex;
		public:
		/*!
		 * Hold the %Mutex locked
		 */
		Lock(const Mutex& tex) : Object(), mutex(tex) {
			mutex.lock();
		}
		/*!
		 * Release the locked %Mutex
		 */
		~Lock() {
			mutex.unlock();
		}
	};

}

#endif /* __PTHREAD_IFACE_H__ */