link_layer.hpp

#ifndef LINK_LAYER_H
#define LINK_LAYER_H

#include <boost/shared_ptr.hpp>
#include <boost/weak_ptr.hpp>

#include "communication_layer.hpp"
#include "mac_protocol.hpp"
#include "simulator.hpp"

class Node;
typedef boost::shared_ptr<Node> NodePtr;

// LinkLayer Class

class LinkLayer : public CommunicationLayer {
friend class MacProtocol;
public:
   typedef boost::shared_ptr<LinkLayer> LinkLayerPtr;

   static inline LinkLayerPtr create(NodePtr node, 
      MacProtocolPtr macProtocol);

   inline LinkLayerPtr thisLinkLayer();

   inline SimulationEndListenerPtr thisSimulationEndListener();

   virtual void simulationEndHandler();

   bool recvFromLayer(CommunicationLayer::Directions direction, 
      PacketPtr packet, t_uint sendingLayerIdx);

   bool recvFromMacProtocol(CommunicationLayer::Directions direction, 
      PacketPtr packet);

   bool channelIsBusy();

   inline CommunicationLayer::Types getLayerType() const;

protected:
   
   LinkLayer(NodePtr node, MacProtocolPtr macProtocol);

private:

   boost::weak_ptr<LinkLayer> m_weakThis;

   static const t_uint m_LINK_LAYER_QUEUE_LENGTH;


   MacProtocolPtr m_macProtocol;

};
typedef boost::shared_ptr<LinkLayer> LinkLayerPtr;

// Inline Functions

inline LinkLayerPtr LinkLayer::create(NodePtr node,
   MacProtocolPtr macProtocol)
{
   LinkLayerPtr p(new LinkLayer(node, macProtocol));
   p->m_weakThis = p;
   // thisLinkLayer() must be called after m_weakThis has
   // been set.
   assert(p->m_macProtocol.get() != 0);
   p->m_macProtocol->setLinkLayer(p->thisLinkLayer());
   Simulator::instance()->addSimulationEndListener(
      p->thisSimulationEndListener());
   return p;
}

inline LinkLayerPtr LinkLayer::thisLinkLayer()
{
   LinkLayerPtr p(m_weakThis);
   return p;
}

inline SimulationEndListenerPtr LinkLayer::thisSimulationEndListener()
{
   SimulationEndListenerPtr p(m_weakThis);
   return p;
}

inline CommunicationLayer::Types LinkLayer::getLayerType() const
{
   return CommunicationLayer::Types_Link;
}

// Overloaded Operators

#endif // LINK_LAYER_H

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