Overwrite existing QueueRegistry entries when a handle is added multiple times. (#306)

Overwrite an existing entry for a given xQueue handle when vQueueAddToRegistry is called with an xQueue handle of a queue that is already in the QueueRegistry.

include/queue.h

@@ -1491,6 +1491,10 @@ BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex ) PRIVILEGED_FUNCTION;
  * does not effect the number of queues, semaphores and mutexes that can be
  * created - just the number that the registry can hold.
  *
+ * If vQueueAddToRegistry is called more than once with the same xQueue
+ * parameter, the registry will store the pcQueueName parameter from the
+ * most recent call to vQueueAddToRegistry.
+ *
  * @param xQueue The handle of the queue being added to the registry.  This
  * is the handle returned by a call to xQueueCreate().  Semaphore and mutex
  * handles can also be passed in here.

queue.c

@@ -2730,24 +2730,37 @@ BaseType_t xQueueIsQueueFullFromISR( const QueueHandle_t xQueue )
         configASSERT( xQueue );
         configASSERT( pcQueueName );
 
+        QueueRegistryItem_t * pxEntryToWrite = NULL;
+
         /* See if there is an empty space in the registry.  A NULL name denotes
          * a free slot. */
         for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
         {
-            if( xQueueRegistry[ ux ].pcQueueName == NULL )
+            /* Replace an existing entry if the queue is already in the registry. */
+            if( xQueueRegistry[ ux ].xHandle == xQueue )
             {
-                /* Store the information on this queue. */
+                pxEntryToWrite = &( xQueueRegistry[ ux ] );
-                xQueueRegistry[ ux ].pcQueueName = pcQueueName;
-                xQueueRegistry[ ux ].xHandle = xQueue;
-
-                traceQUEUE_REGISTRY_ADD( xQueue, pcQueueName );
                 break;
             }
+            /* Otherwise, store in the next empty location */
+            else if( ( NULL == pxEntryToWrite ) && ( xQueueRegistry[ ux ].pcQueueName == NULL ) )
+            {
+                pxEntryToWrite = &( xQueueRegistry[ ux ] );
+            }
             else
             {
                 mtCOVERAGE_TEST_MARKER();
             }
         }
+
+        if( NULL != pxEntryToWrite )
+        {
+            /* Store the information on this queue. */
+            pxEntryToWrite->pcQueueName = pcQueueName;
+            pxEntryToWrite->xHandle = xQueue;
+
+            traceQUEUE_REGISTRY_ADD( xQueue, pcQueueName );
+        }
     }
 
 #endif /* configQUEUE_REGISTRY_SIZE */