InputPortSource.hpp

/***************************************************************************
  tag: Peter Soetens  Thu Oct 22 11:59:08 CEST 2009  InputPortSource.hpp

                        InputPortSource.hpp -  description
                           -------------------
    begin                : Thu October 22 2009
    copyright            : (C) 2009 Peter Soetens
    email                : peter@thesourcworks.com

 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
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 *   License as published by the Free Software Foundation;                 *
 *   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          *
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 *   reasons why the executable file might be covered by the GNU General   *
 *   Public License.                                                       *
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 ***************************************************************************/


#ifndef ORO_INPUT_PORT_SOURCE_HPP
#define ORO_INPUT_PORT_SOURCE_HPP

#include "Channels.hpp"
#include "../base/PortInterface.hpp"

namespace RTT
{ namespace internal {

    template<typename T>
    class InputPortSource : public DataSource<T>
    {
        InputPort<T>* port;
        mutable T mvalue;

    public:
        typedef typename boost::intrusive_ptr<InputPortSource<T> > shared_ptr;

        InputPortSource(InputPort<T>& port)
            : port(&port), mvalue() { }

        void dropPort() {
             port = 0;
        }

        void reset() { port->clear(); }
        bool evaluate() const
        {
            return port->read(mvalue) == NewData;
        }

        typename DataSource<T>::result_t value() const
        { return mvalue; }
        typename DataSource<T>::const_reference_t rvalue() const
        { return mvalue; }
        typename DataSource<T>::result_t get() const
        {
            if ( evaluate() )
                return value();
            else
                return T();
        }
        DataSource<T>* clone() const
        { return new InputPortSource<T>(*port); }
        DataSource<T>* copy( std::map<const base::DataSourceBase*, base::DataSourceBase*>& alreadyCloned ) const
        { return const_cast<InputPortSource<T>*>(this); }
    };
}}

#endif