Semaphore.hpp

/***************************************************************************
  tag: Peter Soetens  Tue Apr 5 16:53:24 CEST 2005  Semaphore.hpp 

                        Semaphore.hpp -  description
                           -------------------
    begin                : Tue April 05 2005
    copyright            : (C) 2005 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                   *
 *   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     *
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 *   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.                                                       *
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 *   This library is distributed in the hope that it will be useful,       *
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 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   Lesser General Public License for more details.                       *
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 *   Foundation, Inc., 59 Temple Place,                                    *
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 ***************************************************************************/
 
 
 

#ifndef RTT_OS_SEMAPHORE_HPP
#define RTT_OS_SEMAPHORE_HPP

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

namespace RTT
{ namespace OS {
    class RTT_API Semaphore 
    {
    private:
        rt_sem_t sem;
    public:
        Semaphore(int count)
        {
            rtos_sem_init( &sem, count );
        }

        ~Semaphore()
        {
            rtos_sem_destroy( &sem );
        }

        void wait()
        {
            rtos_sem_wait( &sem );
        }

        void signal()
        {
            rtos_sem_signal( &sem );
        }

        bool trywait()
        {
            if ( rtos_sem_trywait( &sem ) == 0 )
                return true;
            return false;
        }

        bool waitUntil( Seconds abs_time )
        {
            if (rtos_sem_wait_until( &sem, Seconds_to_nsecs(abs_time) ) == 0 )
                return true;
            return false;
        }

        bool waitUntil( nsecs abs_time )
        {
            if (rtos_sem_wait_until( &sem, abs_time ) == 0 )
                return true;
            return false;
        }

#ifndef OROPKG_OS_MACOSX
        int value()
        {
            return rtos_sem_value( &sem );
        }
#endif
    };
}}

#endif