condition check is not working out as intended, why?

[MatiasMunk]

I'm making a small networked game, still learning networking so I might be missing out on something.
I am using Visual Studio Community 2017.
I am using Allegro 5 for inputs and graphics.
I am using SDL_Net for networking.

- The game is supposed to launch, works fine.
- Every game tick, function HandleEvents(...) gets called in my code.
- The game connects to the server if a mouse click was registered between 0-10 px on the screen, both x and y.

that worked fine, except that the client connected multiple times, so I set a condition so that it will only try and connect 1 client. I did this using a condition:

if(connected) {
    std::cout << "Already connected.." << std::endl;
    } else
    ...

Here's the actual code, so you can see what I have in the function.
function in MenuState.cpp:

    void MenuState::HandleEvents(Input* input, ClientSocket* cs) {
    	if (input->mouseX >= 0 && input->mouseX <= 10 && input->mouseY >= 0 && input->mouseY <= 10) {
    		if (input->mouseB == MouseLDown) {
    			input->set_mouse_state(MouseNDown);
    
    			if (connected == true) {
    				std::cout << "You're already connected." << std::endl;
    			}
    			else if(connected == false) {
    				switch (cs->connectToServer()) {
    				case Packets::SERVER_NOT_RESOLVED:
    					break;
    				case Packets::SERVER_RESOLVED:
    					break;
    				case Packets::SERVER_DOWN:
    					break;
    				case Packets::SERVER_NOT_FULL:
    				{
    					connected = true;
    					std::cout << "Connected to server" << std::endl;
    					receivedMessage = "";
    
    					// Check if we've received a message
    					receivedMessage = cs->checkForIncomingMessages();
    
    					// If so then...
    					if (receivedMessage != "")
    					{
    						// Display the message and then blank it...
    						cs->displayMessage(receivedMessage);
    
    						// ...and then re-display the prompt along with any typed-but-not-yet-sent input
    						//cs->displayPrompt();
    					}
    
    					// Get and deal with input from the user in a non-blocking manner
    					cs->getUserInput();
    				}
    				break;
    				case Packets::SERVER_FULL:
    					break;
    				case Packets::SERVER_NO_RESPONSE:
    					break;
    				}
    			}
    		}
    	}
    }

As you can see, there is clearly a condition check. The condition check works if I remove all networked code in case Packets::SERVER_NOT_FULL:

[salem c]

I think you need to recognise a mouse click event, not a mouse down event.

Down events are going to happen all the time you hold the button down.
It's how things like drag and drop get implemented.

[MatiasMunk]

Hi I used input->set_mouse_state(MouseNDown); after the if(input->mouseB == MouseLDown)
MouseNDown is MouseNoneDown, basically 0, so it only clicks. Not the issue here. sorry I didn't explain that.

The issue is the if else if(connected == false) { not working, it ignores it and it can do the code inside it anyway.

[salem c]

So ignoring all the connection code, does this produce exactly one message for each click?

    		if (input->mouseB == MouseLDown) {
    			input->set_mouse_state(MouseNDown);
    
    			if (connected == true) {
    				std::cout << "You're already connected." << std::endl;
    			}
    			connected = true;

Are you sure of the state that cs->connectToServer() returns?

Networking isn't like opening a file (either you open the file, or you don't).
Likely, you'll need at least three states (not a boolean) to cover
- not connected
- connecting
- connected

This is especially true in event driven code, where nothing ever blocks, waiting for something to finish. Especially where the something can take undefined amounts of time to complete.

[MatiasMunk]

Here is my connectToServer function

int ClientSocket::connectToServer()
{
    // Resolve hostname of server ip and put result in hostResolved integer
    int hostResolved = SDLNet_ResolveHost(&serverIP, serverHostname.c_str(), serverPort);

    // if resolving host fails, else if success.
    if (hostResolved == -1)
    {
        // failed to resolve host, doesn't really matter tho, we got ip.
        return Packets::SERVER_NOT_RESOLVED;
    }
    else // otherwise if we successfully resolved the hostname...
    {
        // get our IP address in dot-quad format (break up 32-bit unsigned host address)
        // split it into an array of four 8-bit unsigned numbers...
        Uint8 * dotQuad = (Uint8*)&serverIP.host;

        dotQuadString  = toString( (unsigned short)dotQuad[0] );
        dotQuadString += ".";
        dotQuadString += toString( (unsigned short)dotQuad[1] );
        dotQuadString += ".";
        dotQuadString += toString( (unsigned short)dotQuad[2] );
        dotQuadString += ".";
        dotQuadString += toString( (unsigned short)dotQuad[3] );

        //Output dotquad string (ip) and output 16bit port
        if (debug)
        {
            cout << "Successfully resolved server to IP: " << dotQuadString;
            cout << ", will use port " << SDLNet_Read16(&serverIP.port) << endl;
        }
    }

    // Open connection between client/server
    clientSocket = SDLNet_TCP_Open(&serverIP);
    if (!clientSocket)
    {
        //Fail, server is down
        return Packets::SERVER_DOWN;
    }
    else // If we successfully opened a connection then check for the server response to our connection
    {
        if (debug) { cout << "Connected, reading status from the server..." << endl; }

        // Add our socket to the socket set for polling
        SDLNet_TCP_AddSocket(socketSet, clientSocket);

        // Wait for up to five seconds for a response from the server.
        int activeSockets = SDLNet_CheckSockets(socketSet, ClientSocket::CONNECTION_TIMEOUT_PERIOD);

        if (debug)
        {
            cout << "There are " << activeSockets << " socket(s) with data on them at the moment." << endl;
        }

        // Check for response from server
        int gotServerResponse = SDLNet_SocketReady(clientSocket);

        if (gotServerResponse != 0)
        {
            // Read the message on the client socket
            int serverResponseByteCount = SDLNet_TCP_Recv(clientSocket, pBuffer, bufferSize);

            if (debug)
            {
                cout << "Message from server: " << pBuffer << "(" << serverResponseByteCount << " bytes)" << endl;
            }

            // Get the contents of the buffer as a string
            string bufferContents = pBuffer;

            // If we got the SERVER_NOT_FULL response from the server then we can join!
            if ( pBuffer == ClientSocket::SERVER_NOT_FULL )
            {
                if (debug) { cout << "Joining server now..." << endl; }
                return Packets::SERVER_NOT_FULL;
            }
            else // Otherwise we must have got the SERVER_FULL response so we can't connect.
            {
                //Tells us server is full
                return Packets::SERVER_FULL;
            }
        }
        else // If there's no activity on the client socket then we've failed to connect
        {
            return Packets::SERVER_NO_RESPONSE;
        }
    }
}

I managed to get a minimal, complete and verifiable example working that produced the same error.
HandleEvents(Input.., ClientSocket..,) function

void MenuState::HandleEvents(Input* input, ClientSocket* cs) {
    if (input->mouseX >= 0 && input->mouseX <= 10 && input->mouseY >= 0 && input->mouseY <= 10) {
        if (input->mouseB == MouseLDown) {
            //Set mouse state to none, so that it doesn't "hold it down" but just clicks once,
            input->set_mouse_state(MouseNDown);

            if (connected == true) {
                std::cout << "You're already connected." << std::endl;
            }
            else {
                switch (cs->connectToServer()) {
                case Packets::SERVER_NOT_FULL:
                    connected = true;
                    std::cout << "Hello" << std::endl; //This never prints, why?
                    break;
                }
            }
        }
    }
}

Is it stuck inside the while loop executing cs->connectToServer()? Please help me locate where in the function connectToServer() it doesn't return and stall the code.
Help is much appreciated.

[salem c]

What while loop, I see no loops.

I might try this.

int cStatus = cs->connectToServer();
switch (cStatus) {
    case Packets::SERVER_NOT_FULL:
        connected = true;
        std::cout << "Hello" << std::endl; //This never prints, why?
        break;
    default:
        std::cout << "OOPS!!!, cStatus=" << cStatus << std::endl;
    }

[MatiasMunk]

Thanks , I had been up all night and did never take into account that it didn't return SERVER_OK || SERVER_NOT_FULL lol