implement statuscode in packets

tcp-mux-server.go

@@ -70,12 +70,21 @@ func (m *TCPServerMux) handleFunction(connection net.Conn, messageType uint32, d
 	if ok {
 		responseType, responseData, err := function(data)
 		if err != nil {
+			errData := []byte(err.Error())
+			err = binary.Write(connection, binary.LittleEndian, Packet{
+				Version:     CurrentPacketVersion,
+				MessageType: responseType,
+				StatusCode:  500,
+				DataLength:  uint32(len(errData)),
+			})
+			_, err = connection.Write(errData)
 			return true, err
 		}
 		err = binary.Write(connection, binary.LittleEndian, Packet{
 			Version:     CurrentPacketVersion,
 			MessageType: responseType,
-			DataLength:  uint64(len(responseData)),
+			StatusCode:  200,
+			DataLength:  uint32(len(responseData)),
 		})
 		if err != nil {
 			return true, err
@@ -100,6 +109,10 @@ func (m *TCPServerMux) HandleConnection(connection net.Conn) error {
 			log.Printf("Error receiving packet: %v\n", err)
 			return err
 		}
+		if packet.Version != CurrentPacketVersion {
+			log.Printf("Incorrect package version: %v\n", err)
+			continue
+		}
 		data, err := GetPacketData(connection, packet.DataLength)
 		if err != nil {
 			log.Printf("Error receiving packet data: %v\n", err)