BufferPolicy.hpp

/***************************************************************************
  tag: Peter Soetens  Wed Jan 18 14:11:39 CET 2006  BufferPolicy.hpp

                        BufferPolicy.hpp -  description
                           -------------------
    begin                : Wed January 18 2006
    copyright            : (C) 2006 Peter Soetens
    email                : peter.soetens@mech.kuleuven.be

 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
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 *   version 2 of the License.                                             *
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 *   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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 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   Lesser General Public License for more details.                       *
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 ***************************************************************************/


#ifndef ORO_CORELIB_BUFFER_POLICY_HPP
#define ORO_CORELIB_BUFFER_POLICY_HPP
#include "os/Semaphore.hpp"

namespace RTT
{

    struct NonBlockingPolicy
    {
        NonBlockingPolicy(unsigned int ) {}
        void push(int /*i*/ = 1 ) {
        }
        void pop(int /*i*/ = 1 ) {
        }
        void reset( int /*i*/ ) {
        }
    };

    struct BlockingPolicy
    {
        BlockingPolicy(unsigned int c) : count(c) {}
        void push(int add = 1) {
            while (add-- > 0) {
                count.signal();
            }
        }
        void pop(int sub = 1) {
            while (sub-- > 0) {
                count.wait();
            }
        }
#ifndef OROPKG_OS_MACOSX
        void reset( int c ) {
            while( c > count.value() )
                count.signal();
            while( c < count.value() )
                count.wait();
        }
#endif
    private:
        OS::Semaphore count;
    };
}
#endif