mutexlock.hpp

机器人开源项目orocos的源代码

/***************************************************************************
  tag: Peter Soetens  Thu Oct 10 16:16:57 CEST 2002  MutexLock.hpp 

                        MutexLock.hpp -  description
                           -------------------
    begin                : Thu October 10 2002
    copyright            : (C) 2002 Peter Soetens
    email                : [e-mail]
 
 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU General Public                   *
 *   License as published by the Free Software Foundation;                 *
 *   version 2 of the License.                                             *
 *                                                                         *
 *   As a special exception, you may use this file as part of a free       *
 *   software library without restriction.  Specifically, if other files   *
 *   instantiate templates or use macros or inline functions from this     *
 *   file, or you compile this file and link it with other files to        *
 *   produce an executable, this file does not by itself cause the         *
 *   resulting executable to be covered by the GNU General Public          *
 *   License.  This exception does not however invalidate any other        *
 *   reasons why the executable file might be covered by the GNU General   *
 *   Public License.                                                       *
 *                                                                         *
 *   This library 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 for more details.                       *
 *                                                                         *
 *   You should have received a copy of the GNU General Public             *
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 *   Foundation, Inc., 59 Temple Place,                                    *
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 *                                                                         *
 ***************************************************************************/ 
 
#ifndef OS_MUTEXLOCK_HPP
#define OS_MUTEXLOCK_HPP

#include "fosi.h"

#include "Mutex.hpp"

namespace RTT
{ namespace OS {
    /**
     * @brief MutexLock is a scope based Monitor, protecting critical
     * sections with a Mutex object through locking and unlocking it.
     */
    class MutexLock
    {

        public:
            /**
             * Create a lock on a Mutex object.
             * 
             * @param mutex The Mutex to be locked.
             */
            MutexLock( OS::MutexInterface &mutex )
            {
                _mutex = &mutex;
                _mutex->lock ();
            }

            /**
             * Remove a lock from a Mutex object
             */
            ~MutexLock()
            {
                _mutex->unlock();
            }

        protected:
            OS::MutexInterface *_mutex;

            MutexLock()
            {}

    };

    /**
     * @brief A MutexTryLock tries to lock an Mutex object on construction
     * and if successful, unlocks it on destruction of the MutexTryLock.
     */
    class MutexTryLock
    {

        public:

            /**
             * Try to lock a Mutex object
             *
             * @param mutex The Mutex which should be attempted to be locked
             */
            MutexTryLock( OS::MutexInterface &mutex )
                    : _mutex( &mutex), successful( mutex.trylock() )
            {
            }

            /**
             * Return if the locking of the Mutex was succesfull
             *
             * @return true when the Mutex is locked
             */
            bool isSuccessful()
            {
                return successful;
            }

            /**
             * Releases, if any, a lock on the previously try-locked Mutex
             */
            ~MutexTryLock()
            {
                if ( successful )
                    _mutex->unlock();
            }

        protected:
            /**
             * The Mutex to lock and unlock
             */
            OS::MutexInterface *_mutex;

        MutexTryLock()
        {}

        private:

            /**
             * Stores the state of success
             */
            bool successful;

    };

}}

#endif