wip reliable unicast (1 hop)

src/mesh/ReliableRouter.h

@@ -0,0 +1,63 @@
+#pragma once
+
+#include "FloodingRouter.h"
+#include "PeriodicTask.h"
+
+/**
+ * This is a mixin that extends Router with the ability to do (one hop only) reliable message sends.
+ */
+class ReliableRouter : public FloodingRouter
+{
+  private:
+  public:
+    /**
+     * Constructor
+     *
+     */
+    // ReliableRouter();
+
+    /**
+     * 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);
+
+    /** Do our retransmission handling */
+    virtual void loop()
+    {
+        doRetransmissions();
+        FloodingRouter::loop();
+    }
+
+  protected:
+    /**
+     * Called from loop()
+     * Handle any packet that is received by an interface on this node.
+     * Note: some packets may merely being passed through this node and will be forwarded elsewhere.
+     *
+     * Note: this method will free the provided packet
+     */
+    virtual void handleReceived(MeshPacket *p);
+
+  private:
+    /**
+     * Send an ack or a nak packet back towards whoever sent idFrom
+     */
+    void sendAckNak(bool isAck, NodeNum to, PacketId idFrom);
+
+    /**
+     * Stop any retransmissions we are doing of the specified node/packet ID pair
+     */
+    void stopRetransmission(NodeNum from, PacketId id);
+
+    /**
+     * Add p to the list of packets to retransmit occasionally.  We will free it once we stop retransmitting.
+     */
+    void startRetransmission(MeshPacket *p);
+
+    /**
+     * Do any retransmissions that are scheduled (FIXME - for the time being called from loop)
+     */
+    void doRetransmissions();
+};