Mutex.hpp

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

                        Mutex.hpp -  description
                           -------------------
    begin                : Thu October 10 2002
    copyright            : (C) 2002 Peter Soetens
    email                : peter.soetens@mech.kuleuven.ac.be
 
 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU General Public                   *
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 *   version 2 of the License.                                             *
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 *   software library without restriction.  Specifically, if other files   *
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 ***************************************************************************/ 
 

#ifndef OS_MUTEX_HPP
#define OS_MUTEX_HPP

#include "fosi.h"
#include "../rtt-config.h"

namespace RTT
{ namespace OS {
    class MutexLock;
    class MutexTryLock;

    class MutexInterface 
    {
    public:
        virtual ~MutexInterface() {}
        virtual void lock() =0;
        virtual void unlock() =0;
        virtual bool trylock() = 0;
    };

    class Mutex : public MutexInterface
    {
        friend class OS::MutexLock;
        friend class OS::MutexTryLock;
    protected:
        rt_mutex_t m;
    public:
            Mutex()
            {
          rtos_mutex_init( &m);
            }

            virtual ~Mutex()
            {
                lock();
                unlock(); // remove this ? then we destroy a locked mutex.
                // race condition here...
                rtos_mutex_destroy( &m );
            }

            virtual void lock ()
            {
                rtos_mutex_lock( &m );
            }

            virtual void unlock()
            {
                rtos_mutex_unlock( &m );
            }

            virtual bool trylock()
            {
                if ( rtos_mutex_trylock( &m ) == 0 )
                    return true;
                return false;
            }

    };

    class MutexRecursive : public MutexInterface
    {
        public:
        MutexRecursive()
        {
    rtos_mutex_rec_init( &recm );
      }

      ~MutexRecursive()
      {
    lock();
    unlock();
    // Race condition here...
    rtos_mutex_rec_destroy( &recm);
      }

      void lock ()
      {
    rtos_mutex_rec_lock( &recm );
        }

      virtual void unlock()
      {
    rtos_mutex_rec_unlock( &recm );
      }

      virtual bool trylock()
      {
    if ( rtos_mutex_rec_trylock( &recm ) == 0 )
      return true;
    return false;
      }

    protected:
      rt_rec_mutex_t recm;
    };

}}

#endif