firmware/src/mesh/DSRRouter.h

#include "ReliableRouter.h"

class DSRRouter : public ReliableRouter
{

  protected:
    /**
     * Every (non duplicate) packet this node receives will be passed through this method.  This allows subclasses to
     * update routing tables etc... based on what we overhear (even for messages not destined to our node)
     */
    virtual void sniffReceived(const MeshPacket *p);

    /**
     * Send a packet on a suitable interface.  This routine will
     * later free() the packet to pool.  This routine is not allowed to stall.
     * If the txmit queue is full it might return an error
     */
    virtual ErrorCode send(MeshPacket *p);

  private:
    /**
     * Does our node appear in the specified route
     */
    bool weAreInRoute(const RouteDiscovery &route);

    /**
     * Given a DSR route, use that route to update our DB of possible routes
     *
     * Note: routes are always listed in the same order - from sender to receipient (i.e. route_replies also use this some order)
     *
     * @param isRequest is true if we are looking at a route request, else we are looking at a reply
     **/
    void updateRoutes(const RouteDiscovery &route, bool isRequest);

    /**
     * send back a route reply (the sender address will be first in the list)
     */
    void sendRouteReply(const RouteDiscovery &route, NodeNum toAppend = 0);

    /**
     * Given a nodenum return the next node we should forward to if we want to reach that node.
     *
     * @return 0 if no route found
     */
    NodeNum getNextHop(NodeNum dest);

    /** Not in our route cache, rebroadcast on their behalf (after adding ourselves to the request route)
     *
     * We will bump down hop_limit in this call.
     */
    void resendRouteRequest(const MeshPacket *p);

    /**
     * Record that forwarder can reach dest for us, but they will need numHops to get there.
     * If our routing tables already have something that can reach that node in fewer hops we will keep the existing route
     * instead.
     */
    void addRoute(NodeNum dest, NodeNum forwarder, uint8_t numHops);

    /**
     * Record that we no longer have a route to the dest
     */
    void removeRoute(NodeNum dest);

    /**
     * Forward the specified packet to the specified node
     */
    void sendNextHop(NodeNum n, const MeshPacket *p);

    /**
     * Send a route error packet towards whoever originally sent this message
     */
    void sendRouteError(const MeshPacket *p, RouteError err);

    /** make a copy of p, start discovery, but only if we don't
     *  already a discovery in progress for that node number.  Caller has already scheduled this message for retransmission
     *  when the discovery is complete.
     */
    void startDiscovery(NodeNum dest);
};