ChannelElement.hpp

/***************************************************************************
  tag: Peter Soetens  Thu Oct 22 11:59:07 CEST 2009  ChannelElement.hpp

                        ChannelElement.hpp -  description
                           -------------------
    begin                : Thu October 22 2009
    copyright            : (C) 2009 Sylvain Joyeux
    email                : sylvain.joyeux@m4x.org

 ***************************************************************************
 *   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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#ifndef ORO_CHANNEL_ELEMENT_HPP
#define ORO_CHANNEL_ELEMENT_HPP

#include <boost/intrusive_ptr.hpp>
#include <boost/call_traits.hpp>
#include "ChannelElementBase.hpp"
#include "../FlowStatus.hpp"

namespace RTT { namespace base {


    template<typename T>
    class ChannelElement : public ChannelElementBase
    {
    public:
        typedef T value_t;
        typedef boost::intrusive_ptr< ChannelElement<T> > shared_ptr;
        typedef typename boost::call_traits<T>::param_type param_t;
        typedef typename boost::call_traits<T>::reference reference_t;

        shared_ptr getOutput()
        {
             return boost::static_pointer_cast< base::ChannelElement<T> >(
                    ChannelElementBase::getOutput());
        }

        shared_ptr getInput()
        {
            return boost::static_pointer_cast< base::ChannelElement<T> >(
                    ChannelElementBase::getInput());
        }

        virtual bool data_sample(param_t sample)
        {
            typename ChannelElement<T>::shared_ptr output = boost::static_pointer_cast< ChannelElement<T> >(getOutput());
            if (output)
                return output->data_sample(sample);
            return false;
        }

        virtual value_t data_sample()
        {
            typename ChannelElement<T>::shared_ptr input = boost::static_pointer_cast< ChannelElement<T> >(getInput());
            if (input)
                return input->data_sample();
            return value_t();
        }

        virtual bool write(param_t sample)
        {
            typename ChannelElement<T>::shared_ptr output = boost::static_pointer_cast< ChannelElement<T> >(getOutput());
            if (output)
                return output->write(sample);
            return false;
        }

        virtual FlowStatus read(reference_t sample, bool copy_old_data)
        {
            typename ChannelElement<T>::shared_ptr input = this->getInput();
            if (input)
                return input->read(sample, copy_old_data);
            else
                return NoData;
        }
    };
}}

#endif