cas.hpp

机器人开源项目orocos的源代码

/***************************************************************************
  tag: Peter Soetens  Tue Dec 21 22:43:07 CET 2004  CAS.hpp 

                        CAS.hpp -  description
                           -------------------
    begin                : Tue December 21 2004
    copyright            : (C) 2004 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     *
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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 OS_COMMON_CAS_HPP
#define OS_COMMON_CAS_HPP

#include "oro_system.h"

namespace RTT
{ namespace OS {
    /**
     * Compare And Swap.
     * Also known as Compare Exchange (cmpxch).
     * If \a addr contains \a expected, replace
     * it with \a value, and return \a true. Otherwise,
     * return \a false.
     */
    template< class T, class V, class W >
    bool CAS( volatile T* addr, const V& expected, const W& value) {
        return expected == oro_cmpxchg(addr, expected, value);
    }

}}

#endif