don't respond to broadcast SET PIDs

rdm/message.h

@@ -61,6 +61,7 @@ struct Message
       bool checksum_fail   : 1;
       bool incorrect_sc    : 1;
       bool incorrect_sub_sc: 1;
+      bool do_no_send      : 1;
     };
   };
 

rdm/responder.cpp

@@ -170,12 +170,30 @@ void Responder::receive(const Message *message)
       break;
     default:
       delete response;
-      response = nullptr;
-      break;
+      return;
   }
 
-  if (response)
-    queued_messages_.push(response);
+  if (!response)
+    return;
+
+  /// 5.3 Broadcast Message Addressing
+  /// When Broadcast Addressing is used for non-Discovery messages, the
+  /// responders shall not send a response.
+  if (message->destination.isBroadcast() &&
+      message->commandClass != DISCOVERY_COMMAND)
+    {
+      delete response;
+      return;
+    }
+
+  if (response->do_no_send)
+    {
+      delete response;
+      return;
+    }
+
+  queued_messages_.push(response);
+}
 
 
 /**
@@ -255,10 +273,12 @@ void Responder::rxSet(const Message *message, Message* response)
           Message * rsp = new Message(*response);
           rsp->subDevice = num;
           dev->set(message, rsp);
-          queued_messages_.push(rsp);
+          if (message->destination.isBroadcast())
+            delete rsp;
+          else
+            queued_messages_.push(rsp);
         }
-      delete response;
-      response = nullptr;
+      response->do_no_send = true;
       return;
     }
 

rdm/uid.h

@@ -36,6 +36,9 @@ struct UID {
       uint32_t device;
     };
   };
+  bool isBroadcast() const {
+    return (uid == BROADCAST_ALL_DEVICES_ID || device == ALL_DEVICE_ID_MASK);
+  }
   friend bool operator== (const UID& a, const UID& b)
   {
     if (a.uid == BROADCAST_ALL_DEVICES_ID || b.uid == BROADCAST_ALL_DEVICES_ID)