EventChannel.h

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/*******************************************************************************
 *
 * Copyright (c) 2008-2010 Michael Schulze <mschulze@ivs.cs.uni-magdeburg.de>
 *                    2010 Philipp Werner <philipp.werner@st.ovgu.de>
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#ifndef __EventChannel_h__
#define __EventChannel_h__

#include "mw/common/Subject.h"
#include "mw/common/Event.h"
#include "mw/el/EventChannelHandler.h"
#include "mw/attributes/AttributeSet.h"

#include "object/Chain.h"
#include "case/Delegate.h"

namespace famouso {
    namespace mw {
        namespace api {

            template < class ECH >
            class EventChannel : public Chain {
                    // the 64Bit subject
                    Subject _subj;
                    // definition of the short network names of a subjectes
                    typename ECH::SNN _snn;

                protected:
                    struct MWAction {
                        enum {
                            get_requirements,

                            start_real_time_delivery
                        } action;
                        uint8_t * buffer;
                    };

                    util::Delegate<MWAction &, uint16_t> mw_action_trampoline;

                    uint16_t dummy_mw_action_impl(MWAction & mw_action) {
                        if (mw_action.action == MWAction::get_requirements) {
                            // Return empty requirement attribute set
                            typedef attributes::AttributeSet<> ReqAttr;
                            if (mw_action.buffer) {
                                new (mw_action.buffer) ReqAttr;
                            }
                            return ReqAttr::overallSize;
                        }
                        return 0;
                    }

                    template <class LL, class EL> friend class ManagementLayer;

                public:
                    typedef ECH eventChannelHandler;

                    ECH& ech() const {
                        return famouso::mw::el::EventChannelHandler<ECH>::ech();
                    }

                    typename ECH::SNN& snn() {
                        return _snn;
                    }

                    const typename ECH::SNN& snn() const {
                        return _snn;
                    }

                    const Subject &subject() const {
                        return _subj;
                    }

                    uint16_t get_requirements(uint8_t * buffer) const {
                        MWAction mwa;
                        mwa.action = MWAction::get_requirements;
                        mwa.buffer = buffer;
                        return mw_action_trampoline(mwa);
                    }

                protected:
                    EventChannel(const Subject& s) : _subj(s) {
                        mw_action_trampoline.template bind<
                                EventChannel,
                                &EventChannel::dummy_mw_action_impl>(this);
                    }


                private:
                    // Private copy constructor and copy ensure that event channels
                    // cannot be copied
                    EventChannel(const EventChannel<ECH> & e);
                    const EventChannel<ECH> & operator=(const EventChannel<ECH> &);
            };

        } // namespace api
    } // namespace mw
} // namespace famouso


#endif /* __EventChannel_h__ */