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c++qtssltwitch

Qt QSSlSocket - SEGFAULT on 'connectToHostEncrypted();'


I am attempting to connect to the Twitch chat server via SSL and I basically copied and pasted some code from the Secure SSL Connection example in QT. When I can connectToHostEncrypted it all crashed. Any help is greatly appreciated

Relative code:

void MainWindow::secureConnect()
{
    if (!socket) {
        socket = new QSslSocket(this);
        connect(socket, SIGNAL(stateChanged(QAbstractSocket::SocketState)),
                this, SLOT(socketStateChanged(QAbstractSocket::SocketState)));

    connect(socket, SIGNAL(encrypted()),
            this, SLOT(socketEncrypted()));

    connect(socket, SIGNAL(error(QAbstractSocket::SocketError)),
            this, SLOT(socketError(QAbstractSocket::SocketError)));

    connect(socket, SIGNAL(sslErrors(QList<QSslError>)),
            this, SLOT(sslErrors(QList<QSslError>)));

    connect(socket, SIGNAL(readyRead()),
            this, SLOT(socketReadyRead()));
    }
    qDebug() << 2;
    socket->connectToHostEncrypted("irc.chat.twitch.tv", 443);
    QEventLoop loop;
    connect(socket, SIGNAL(connected()), &loop, SLOT(quit()));
    loop.exec();
    qDebug() << 5;
    sendData("PASS oauth:" + TwitchAccessToken);
    sendData("NICK ThatRedstoneGT");
    sendData("JOIN smartguy316");
    sendData("PRIVMSG Hello!");
}

Declaration:

Public:
QSslSocket *socket:

Solution

  • Putting this as an answer as I'm not sure I've managed to get my point across in the comments.

    You have a class MainWindow with a member socket. Keeping things to a minimum let's say it's...

    class MainWindow {
    public:
      MainWindow();
      void secureConnect();
      void sendData(QString text);
      QSslSocket *socket:
    };
    

    Now, I would expect the constructor implementation to look something like...

    MainWindow::MainWindow ()
      : socket(nullptr)
      {}
    

    If you don't initialize socket to nullptr before MainWindow::secureConnect is called then it will have some random value. In which case...

    if (!socket) {
    

    will fail meaning that the block containing...

    socket = new QSslSocket(this);
    

    will never be executed.

    By way of a test, can you run your code under a debugger, set a breakpoint on the line...

    if (!socket) {
    

    and check the value of socket. The first time that line is hit socket should be null. Is it?