Add dropped packet count to LocalStats (#8207)

* Add dropped packet count to LocalStats
In case the transmit queue was full

* Trunked

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/mesh/MeshPacketQueue.cpp

@@ -65,7 +65,7 @@ void fixPriority(meshtastic_MeshPacket *p)
 }
 
 /** enqueue a packet, return false if full */
-bool MeshPacketQueue::enqueue(meshtastic_MeshPacket *p)
+bool MeshPacketQueue::enqueue(meshtastic_MeshPacket *p, bool *dropped)
 {
     // no space - try to replace a lower priority packet in the queue
     if (queue.size() >= maxLen) {
@@ -73,9 +73,16 @@ bool MeshPacketQueue::enqueue(meshtastic_MeshPacket *p)
         if (!replaced) {
             LOG_WARN("TX queue is full, and there is no lower-priority packet available to evict in favour of 0x%08x", p->id);
         }
+        if (dropped) {
+            *dropped = true;
+        }
         return replaced;
     }
 
+    if (dropped) {
+        *dropped = false;
+    }
+
     // Find the correct position using upper_bound to maintain a stable order
     auto it = std::upper_bound(queue.begin(), queue.end(), p, CompareMeshPacketFunc);
     queue.insert(it, p); // Insert packet at the found position

src/mesh/MeshPacketQueue.h

@@ -19,8 +19,10 @@ class MeshPacketQueue
   public:
     explicit MeshPacketQueue(size_t _maxLen);
 
-    /** enqueue a packet, return false if full */
-    bool enqueue(meshtastic_MeshPacket *p);
+    /** enqueue a packet, return false if full
+     * @param dropped Optional pointer to a bool that will be set to true if a packet was dropped
+     */
+    bool enqueue(meshtastic_MeshPacket *p, bool *dropped = nullptr);
 
     /** return true if the queue is empty */
     bool empty();

src/mesh/RadioLibInterface.cpp

@@ -177,7 +177,12 @@ ErrorCode RadioLibInterface::send(meshtastic_MeshPacket *p)
     printPacket("enqueue for send", p);
 
     LOG_DEBUG("txGood=%d,txRelay=%d,rxGood=%d,rxBad=%d", txGood, txRelay, rxGood, rxBad);
-    ErrorCode res = txQueue.enqueue(p) ? ERRNO_OK : ERRNO_UNKNOWN;
+    bool dropped = false;
+    ErrorCode res = txQueue.enqueue(p, &dropped) ? ERRNO_OK : ERRNO_UNKNOWN;
+
+    if (dropped) {
+        txDrop++;
+    }
 
     if (res != ERRNO_OK) { // we weren't able to queue it, so we must drop it to prevent leaks
         packetPool.release(p);
@@ -359,11 +364,15 @@ void RadioLibInterface::clampToLateRebroadcastWindow(NodeNum from, PacketId id)
     meshtastic_MeshPacket *p = txQueue.remove(from, id, true, false);
     if (p) {
         p->tx_after = millis() + getTxDelayMsecWeightedWorst(p->rx_snr);
-        if (txQueue.enqueue(p)) {
+        bool dropped = false;
+        if (txQueue.enqueue(p, &dropped)) {
             LOG_DEBUG("Move existing queued packet to the late rebroadcast window %dms from now", p->tx_after - millis());
         } else {
             packetPool.release(p);
         }
+        if (dropped) {
+            txDrop++;
+        }
     }
 }
 

src/mesh/RadioLibInterface.h

@@ -116,6 +116,7 @@ class RadioLibInterface : public RadioInterface, protected concurrency::Notified
      * Debugging counts
      */
     uint32_t rxBad = 0, rxGood = 0, txGood = 0, txRelay = 0;
+    uint16_t txDrop = 0;
 
   public:
     RadioLibInterface(LockingArduinoHal *hal, RADIOLIB_PIN_TYPE cs, RADIOLIB_PIN_TYPE irq, RADIOLIB_PIN_TYPE rst,