From 7a0358109ade248626c61e2bb53b3f5275162012 Mon Sep 17 00:00:00 2001
From: Giovanni Harting <539@idlegandalf.com>
Date: Tue, 12 Dec 2017 20:03:18 +0100
Subject: [PATCH] added message size bytes

---
 ledd.go | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/ledd.go b/ledd.go
index fd2a890..ff5a586 100644
--- a/ledd.go
+++ b/ledd.go
@@ -184,7 +184,7 @@ func (manager *BackendManager) start() {
 				log.Warningf("[%s] Failed to encode protobuf: %s", backend.niceName(), err)
 			}
 
-			backend.data <- data
+			backend.data <- prepareProtobuf(data)
 		case backend := <-manager.unregister:
 			if _, ok := manager.backends[backend.name]; ok {
 				log.Debugf("[%s] Backend %s removed: connection terminated", LOG_BACKEND, backend.socket.RemoteAddr())
@@ -236,12 +236,12 @@ func (manager *BackendManager) receive(backend *Backend) {
 		}
 
 		if length > 0 {
-			msgLen := binary.BigEndian.Uint32(message[0:3])
+			msgLen := binary.BigEndian.Uint32(message[0:4])
 
 			log.Debugf("[%s] Read %d bytes, first protobuf is %d long", backend.niceName(), length, msgLen)
 
 			backendMsg := &ledd.BackendWrapperMessage{}
-			err = proto.Unmarshal(message[4:msgLen], backendMsg)
+			err = proto.Unmarshal(message[4:msgLen+1], backendMsg)
 			if err != nil {
 				log.Warningf("[%s] Couldn't decode protobuf msg!", backend.niceName())
 				continue
@@ -313,12 +313,12 @@ func (manager *ClientManager) receive(client *Client) {
 			break
 		}
 		if length > 0 {
-			msgLen := binary.BigEndian.Uint32(message[0:3])
+			msgLen := binary.BigEndian.Uint32(message[0:4])
 
 			log.Debugf("[%s] Read %d bytes, first protobuf is %d long", client.socket.RemoteAddr(), length, msgLen)
 
 			clientMsg := &ledd.ClientWrapperMessage{}
-			err = proto.Unmarshal(message[4:msgLen], clientMsg)
+			err = proto.Unmarshal(message[4:msgLen+1], clientMsg)
 			if err != nil {
 				log.Warningf("[%s] Couldn't decode protobuf msg!", client.socket.RemoteAddr())
 				continue
@@ -341,7 +341,7 @@ func (manager *ClientManager) receive(client *Client) {
 					log.Errorf("[%s] Error encoding protobuf: %s", client.socket.RemoteAddr(), err)
 				}
 
-				client.data <- data
+				client.data <- prepareProtobuf(data)
 			case *ledd.ClientWrapperMessage_MAddLed:
 				backend, ok := backManager.backends[msg.MAddLed.Backend]
 				if !ok {
@@ -407,7 +407,13 @@ func (led *LED) setColor(color colorful.Color) {
 		log.Warningf("[%s] Failed to encode protobuf msg to %s: %s", led.name, backend.name, err)
 	}
 
-	backend.data <- data
+	backend.data <- prepareProtobuf(data)
+}
+
+func prepareProtobuf(data []byte) []byte {
+	size := make([]byte, 4)
+	binary.BigEndian.PutUint32(size, uint32(len(data)))
+	return append(size, data...)
 }
 
 // MAIN