Fix crush single message inside long message (#190)

* Add test for single message inside long message

* Fix crush single message inside long message

Co-authored-by: p.kuskov <[email protected]>

Author: a1ien

canard.c

@@ -319,11 +319,12 @@ int16_t canardHandleRxFrame(CanardInstance* ins, const CanardCANFrame* frame, ui
     const bool first_frame = IS_START_OF_TRANSFER(tail_byte);
     const bool not_previous_tid =
         computeTransferIDForwardDistance((uint8_t) rx_state->transfer_id, TRANSFER_ID_FROM_TAIL_BYTE(tail_byte)) > 1;
+    const bool incomplete_frame = rx_state->buffer_blocks != NULL;
 
     const bool need_restart =
             (not_initialized) ||
             (tid_timed_out) ||
-            (first_frame && not_previous_tid);
+            (first_frame && (not_previous_tid || incomplete_frame));
 
     if (need_restart)
     {

tests/test_rxerr.cpp

@@ -372,3 +372,37 @@ TEST_CASE("canardHandleRxFrame OOM handling, Correctness")
     err = canardHandleRxFrame(&canard, &frame, 1);
     REQUIRE(-CANARD_ERROR_OUT_OF_MEMORY == err);
 }
+
+TEST_CASE("canardHandleRxFrame unusual single frame, Correctness")
+{
+    uint8_t canard_memory_pool[1024];
+    CanardInstance canard;
+    CanardCANFrame frame;
+    int16_t err;
+
+    g_should_accept = true;
+
+    //Open canard to accept all transfers with a node ID of 20
+    canardInit(&canard, canard_memory_pool, sizeof(canard_memory_pool),
+               onTransferReceived, shouldAcceptTransfer, &canard);
+    canardSetLocalNodeID(&canard, 20);
+
+    frame.data[7] = CONSTRUCT_TAIL_BYTE(1, 0, 0, 1);
+    frame.id = CONSTRUCT_SVC_ID(0, 0, 1, 20, 0);
+    frame.data_len = 8;                             //Data length MUST be full packet
+    err = canardHandleRxFrame(&canard, &frame, 1);
+    REQUIRE(CANARD_OK == err);
+
+
+    frame.data[7] = CONSTRUCT_TAIL_BYTE(0, 0, 1, 1);
+    frame.id = CONSTRUCT_SVC_ID(0, 0, 1, 20, 0);
+    frame.data_len = 8;                             //Data length MUST be full packet
+    err = canardHandleRxFrame(&canard, &frame, 1);
+    REQUIRE(CANARD_OK == err);
+
+    frame.data[1] = CONSTRUCT_TAIL_BYTE(1, 1, 1, 1);
+    frame.id = CONSTRUCT_SVC_ID(0, 0, 1, 20, 0);
+    frame.data_len = 2;                             //Data length MUST be full packet
+    err = canardHandleRxFrame(&canard, &frame, 1);
+    REQUIRE(CANARD_OK == err);
+}