Orocos Real-Time Toolkit  2.6.0
ChannelElement.hpp
00001 /***************************************************************************
00002   tag: Peter Soetens  Thu Oct 22 11:59:07 CEST 2009  ChannelElement.hpp
00003 
00004                         ChannelElement.hpp -  description
00005                            -------------------
00006     begin                : Thu October 22 2009
00007     copyright            : (C) 2009 Sylvain Joyeux
00008     email                : sylvain.joyeux@m4x.org
00009 
00010  ***************************************************************************
00011  *   This library is free software; you can redistribute it and/or         *
00012  *   modify it under the terms of the GNU General Public                   *
00013  *   License as published by the Free Software Foundation;                 *
00014  *   version 2 of the License.                                             *
00015  *                                                                         *
00016  *   As a special exception, you may use this file as part of a free       *
00017  *   software library without restriction.  Specifically, if other files   *
00018  *   instantiate templates or use macros or inline functions from this     *
00019  *   file, or you compile this file and link it with other files to        *
00020  *   produce an executable, this file does not by itself cause the         *
00021  *   resulting executable to be covered by the GNU General Public          *
00022  *   License.  This exception does not however invalidate any other        *
00023  *   reasons why the executable file might be covered by the GNU General   *
00024  *   Public License.                                                       *
00025  *                                                                         *
00026  *   This library is distributed in the hope that it will be useful,       *
00027  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
00028  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
00029  *   Lesser General Public License for more details.                       *
00030  *                                                                         *
00031  *   You should have received a copy of the GNU General Public             *
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00033  *   Foundation, Inc., 59 Temple Place,                                    *
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00035  *                                                                         *
00036  ***************************************************************************/
00037 
00038 
00039 #ifndef ORO_CHANNEL_ELEMENT_HPP
00040 #define ORO_CHANNEL_ELEMENT_HPP
00041 
00042 #include <boost/intrusive_ptr.hpp>
00043 #include <boost/call_traits.hpp>
00044 #include "ChannelElementBase.hpp"
00045 #include "../FlowStatus.hpp"
00046 
00047 namespace RTT { namespace base {
00048 
00049 
00053     template<typename T>
00054     class ChannelElement : public ChannelElementBase
00055     {
00056     public:
00057         typedef T value_t;
00058         typedef boost::intrusive_ptr< ChannelElement<T> > shared_ptr;
00059         typedef typename boost::call_traits<T>::param_type param_t;
00060         typedef typename boost::call_traits<T>::reference reference_t;
00061 
00062         shared_ptr getOutput()
00063         {
00064              return boost::static_pointer_cast< base::ChannelElement<T> >(
00065                     ChannelElementBase::getOutput());
00066         }
00067 
00068         shared_ptr getInput()
00069         {
00070             return boost::static_pointer_cast< base::ChannelElement<T> >(
00071                     ChannelElementBase::getInput());
00072         }
00073 
00082         virtual bool data_sample(param_t sample)
00083         {
00084             typename ChannelElement<T>::shared_ptr output = boost::static_pointer_cast< ChannelElement<T> >(getOutput());
00085             if (output)
00086                 return output->data_sample(sample);
00087             return false;
00088         }
00089 
00090         virtual value_t data_sample()
00091         {
00092             typename ChannelElement<T>::shared_ptr input = boost::static_pointer_cast< ChannelElement<T> >(getInput());
00093             if (input)
00094                 return input->data_sample();
00095             return value_t();
00096         }
00097 
00103         virtual bool write(param_t sample)
00104         {
00105             typename ChannelElement<T>::shared_ptr output = boost::static_pointer_cast< ChannelElement<T> >(getOutput());
00106             if (output)
00107                 return output->write(sample);
00108             return false;
00109         }
00110 
00116         virtual FlowStatus read(reference_t sample, bool copy_old_data)
00117         {
00118             typename ChannelElement<T>::shared_ptr input = this->getInput();
00119             if (input)
00120                 return input->read(sample, copy_old_data);
00121             else
00122                 return NoData;
00123         }
00124     };
00125 }}
00126 
00127 #endif
00128