Deliver locally-generated replies addressed to us to the phone (#11185)

* Deliver locally-generated replies addressed to us to the phone

Config get/set from the phone times out on every device: the client sends an
admin request, the node handles it, and the response is silently dropped
before it reaches the phone queue.

#10967 changed Router::sendLocal's isToUs branch from enqueueReceivedMessage()
to handleReceived(p, src), so a local packet keeps its RxSource instead of
being relabeled RX_SRC_RADIO by the queue round-trip. That is the right call
for the new policy gates, but module replies go out through
MeshService::sendToMesh() with the default RX_SRC_LOCAL, and a reply to a
phone-originated request is addressed to our own node (setReplyTo resolves
from == 0 to ourNodeNum). Those replies now re-enter callModules as
RX_SRC_LOCAL, where the loopback gate skips every module whose loopbackOk is
false - including RoutingModule, whose promiscuous sniff is the only path that
moves a received packet into toPhoneQueue. The reply is released, never sent.

Requests still work, because the phone's own packets arrive as RX_SRC_USER and
pass the gate, so a set_config is applied and only its acknowledgement is lost.
That is why a client can connect and download config but times out on every
config screen and every setter.

Deliver the phone's copy from sendToMesh() instead: for a local packet
addressed to us, the loopback gate is doing its job in keeping the packet away
from module re-dispatch, and the phone copy is exactly what is missing. Setting
loopbackOk on RoutingModule would instead echo every locally-generated
broadcast back to the phone, and relabeling replies RX_SRC_RADIO would undo the
origin separation #10967 added.

Also stop reporting ERRNO_SHOULD_RELEASE (35) to the phone in the QueueStatus
for these packets. It means "caller frees", not a send failure, and the same
hunk changed it from the 0 the phone used to see.

* Address review: trim comments, assert the QueueStatus count

Condense the added comments to the one-or-two-line house style; the rationale
lives in the commit message and PR.

The reply test drained QueueStatus records in a while loop, which would have
passed just as happily on an empty queue. Count them and require both the
request's and the reply's.

src/mesh/MeshService.cpp

@@ -324,13 +324,20 @@ void MeshService::sendToMesh(meshtastic_MeshPacket *p, RxSource src, bool ccToPh
     uint32_t mesh_packet_id = p->id;
     nodeDB->updateFrom(*p); // update our local DB for this packet (because phone might have sent position packets etc...)
 
+    // callModules' loopback gate keeps RX_SRC_LOCAL packets from RoutingModule, the only module
+    // that forwards to the phone, so deliver our own reply's copy here or the client never sees it.
+    const bool localDelivery = isToUs(p);
+    if (src == RX_SRC_LOCAL && localDelivery)
+        ccToPhone = true;
+
     // Note: We might return !OK if our fifo was full, at that point the only option we have is to drop it
     ErrorCode res = router->sendLocal(p, src);
 
     /* NOTE(pboldin): Prepare and send QueueStatus message to the phone as a
      * high-priority message. */
     meshtastic_QueueStatus qs = router->getQueueStatus();
-    ErrorCode r = sendQueueStatusToPhone(qs, res, mesh_packet_id);
+    // SHOULD_RELEASE means "caller frees", not a send failure, so don't report it as one.
+    ErrorCode r = sendQueueStatusToPhone(qs, (res == ERRNO_SHOULD_RELEASE && localDelivery) ? ERRNO_OK : res, mesh_packet_id);
     if (r != ERRNO_OK) {
         LOG_DEBUG("Can't send status to phone");
     }

test/test_mesh_module/test_main.cpp

@@ -256,6 +256,8 @@ void tearDown(void)
 
     while (auto *status = mockService->getQueueStatusForPhone())
         mockService->releaseQueueStatusToPool(status);
+    while (auto *toPhone = mockService->getForPhone())
+        mockService->releaseToPool(toPhone);
     delete mockService;
     mockService = nullptr;
     service = nullptr;
@@ -471,6 +473,74 @@ static void test_dispatch_realNeighborInfoCannotShadowTelemetryOwner()
     TEST_ASSERT_EQUAL_UINT32(0, mockRoutingModule->ackNaks.size());
 }
 
+// A reply addressed to ourselves reaches the phone queue, with SHOULD_RELEASE reported as success.
+static void test_localReplyToSelf_isDeliveredToPhone()
+{
+    meshtastic_MeshPacket reply = meshtastic_MeshPacket_init_zero;
+    reply.from = LOCAL_NODE;
+    reply.to = LOCAL_NODE;
+    reply.id = 0xABCD1234;
+    reply.which_payload_variant = meshtastic_MeshPacket_decoded_tag;
+    reply.decoded.portnum = meshtastic_PortNum_ADMIN_APP;
+    reply.decoded.request_id = 0x12345678;
+
+    service->sendToMesh(packetPool.allocCopy(reply)); // default src == RX_SRC_LOCAL, as callModules sends replies
+
+    meshtastic_MeshPacket *toPhone = mockService->getForPhone();
+    TEST_ASSERT_NOT_NULL(toPhone);
+    TEST_ASSERT_EQUAL_UINT32(0xABCD1234, toPhone->id);
+    TEST_ASSERT_EQUAL_UINT32(0x12345678, toPhone->decoded.request_id);
+    mockService->releaseToPool(toPhone);
+    TEST_ASSERT_NULL(mockService->getForPhone()); // exactly one delivery
+
+    meshtastic_QueueStatus *qs = mockService->getQueueStatusForPhone();
+    TEST_ASSERT_NOT_NULL(qs);
+    TEST_ASSERT_EQUAL(ERRNO_OK, qs->res);
+    mockService->releaseQueueStatusToPool(qs);
+
+    TEST_ASSERT_EQUAL_UINT32(0, mockRouter->sentPackets.size()); // nothing went toward the radio
+}
+
+// Full loop: a phone-originated want_response request (from == 0, RX_SRC_USER) dispatched
+// through the real router must produce a module reply that reaches the phone queue.
+static void test_phoneRequest_replyReachesPhone()
+{
+    auto *replyOwner = registerDispatchModule(
+        new SyntheticReplyModule("private-owner", meshtastic_PortNum_PRIVATE_APP, meshtastic_PortNum_PRIVATE_APP));
+
+    meshtastic_MeshPacket request = meshtastic_MeshPacket_init_zero;
+    request.from = 0; // phone-originated, as MeshService::handleToRadio stamps it
+    request.to = LOCAL_NODE;
+    request.id = 0x5EED0001;
+    request.which_payload_variant = meshtastic_MeshPacket_decoded_tag;
+    request.decoded.portnum = meshtastic_PortNum_PRIVATE_APP;
+    request.decoded.want_response = true;
+
+    service->sendToMesh(packetPool.allocCopy(request), RX_SRC_USER);
+
+    TEST_ASSERT_EQUAL_UINT32(1, replyOwner->allocReplyCalls);
+
+    meshtastic_MeshPacket *toPhone = mockService->getForPhone();
+    TEST_ASSERT_NOT_NULL(toPhone);
+    TEST_ASSERT_EQUAL(meshtastic_PortNum_PRIVATE_APP, toPhone->decoded.portnum);
+    TEST_ASSERT_EQUAL_UINT32(0x5EED0001, toPhone->decoded.request_id);
+    TEST_ASSERT_EQUAL_UINT32(LOCAL_NODE, toPhone->to);
+    mockService->releaseToPool(toPhone);
+    TEST_ASSERT_NULL(mockService->getForPhone()); // the request itself must not echo back
+
+    // One QueueStatus for the request, one for the reply, both reporting success
+    uint32_t statuses = 0;
+    while (auto *qs = mockService->getQueueStatusForPhone()) {
+        TEST_ASSERT_EQUAL(ERRNO_OK, qs->res);
+        mockService->releaseQueueStatusToPool(qs);
+        statuses++;
+    }
+    TEST_ASSERT_EQUAL_UINT32(2, statuses);
+
+    TEST_ASSERT_EQUAL_UINT32(0, mockRouter->sentPackets.size());
+    TEST_ASSERT_EQUAL_UINT32(0, mockRoutingModule->ackNaks.size());
+}
+
 void setup()
 {
     initializeTestEnvironment();
@@ -495,6 +565,8 @@ void setup()
     RUN_TEST(test_dispatch_noResponderSendsNak);
     RUN_TEST(test_dispatch_ignoreRequestIsClearedPerPacket);
     RUN_TEST(test_dispatch_realNeighborInfoCannotShadowTelemetryOwner);
+    RUN_TEST(test_localReplyToSelf_isDeliveredToPhone);
+    RUN_TEST(test_phoneRequest_replyReachesPhone);
     exit(UNITY_END());
 }