Fail on message sending if too big

CURA-11103

Previously we would correctly send the message, but be unable to parse
it at receiving time. Now we apply a more fail-fast strategy.

Author: wawanbreton

src/Socket_p.h

@@ -43,7 +43,7 @@
 #define VERSION_MINOR 0
 
 #define ARCUS_SIGNATURE 0x2BAD
-#define SIG(n) (((n)&0xffff0000) >> 16)
+#define SIG(n) (((n) & 0xffff0000) >> 16)
 
 #define SOCKET_CLOSE 0xf0f0f0f0
 
@@ -360,7 +360,11 @@ void Socket::Private::sendMessage(const MessagePtr& message)
     }
 
     std::string data = message->SerializeAsString();
-    if (platform_socket.writeBytes(data.size(), data.data()) == -1)
+    if (data.size() > message_size_maximum)
+    {
+        error(ErrorCode::SendFailedError, "Message is too big to be sent");
+    }
+    else if (platform_socket.writeBytes(data.size(), data.data()) == -1)
     {
         error(ErrorCode::SendFailedError, "Could not send message data");
     }
@@ -571,4 +575,4 @@ void Socket::Private::checkConnectionState()
 }
 } // namespace Arcus
 
-#endif // SOCKET_P_H
+#endif // SOCKET_P_H