Объяснение кода

BrowserApplication::BrowserApplication(int &argc, char **argv)
    : QApplication(argc, argv)
    , m_localServer(0)
{
    QCoreApplication::setOrganizationName(QLatin1String("Trolltech"));
    QCoreApplication::setApplicationName(QLatin1String("demobrowser"));
    QCoreApplication::setApplicationVersion(QLatin1String("0.1"));
#ifdef Q_WS_QWS
    // Use a different server name for QWS so we can run an X11
    // browser and a QWS browser in parallel on the same machine for
    // debugging
    QString serverName = QCoreApplication::applicationName() + QLatin1String("_qws");
#else
    QString serverName = QCoreApplication::applicationName();
#endif
    QLocalSocket socket;
    socket.connectToServer(serverName);
    if (socket.waitForConnected(500)) {
        QTextStream stream(&socket);
        QStringList args = QCoreApplication::arguments();
        if (args.count() > 1)
            stream << args.last();
        else
            stream << QString();
        stream.flush();
        socket.waitForBytesWritten();
        return;
    }
 
#if defined(Q_WS_MAC)
    QApplication::setQuitOnLastWindowClosed(false);
#else
    QApplication::setQuitOnLastWindowClosed(true);
#endif
 
    m_localServer = new QLocalServer(this);
    connect(m_localServer, SIGNAL(newConnection()),
            this, SLOT(newLocalSocketConnection()));
    if (!m_localServer->listen(serverName)) {
        if (m_localServer->serverError() == QAbstractSocket::AddressInUseError
            && QFile::exists(m_localServer->serverName())) {
            QFile::remove(m_localServer->serverName());
            m_localServer->listen(serverName);
        }
    }
 
#ifndef QT_NO_OPENSSL
    if (!QSslSocket::supportsSsl()) {
    QMessageBox::information(0, "Demo Browser",
                 "This system does not support OpenSSL. SSL websites will not be available.");
    }
#endif
 
    QDesktopServices::setUrlHandler(QLatin1String("http"), this, "openUrl");
    QString localSysName = QLocale::system().name();
 
    installTranslator(QLatin1String("qt_") + localSysName);
 
    QSettings settings;
    settings.beginGroup(QLatin1String("sessions"));
    m_lastSession = settings.value(QLatin1String("lastSession")).toByteArray();
    settings.endGroup();
 
#if defined(Q_WS_MAC)
    connect(this, SIGNAL(lastWindowClosed()),
            this, SLOT(lastWindowClosed()));
#endif
 
    QTimer::singleShot(0, this, SLOT(postLaunch()));
}

QString serverName = QCoreApplication::applicationName()
 socket.connectToServer(serverName);
    if (socket.waitForConnected(500)) {
        QTextStream stream(&socket);
        QStringList args = QCoreApplication::arguments();
        if (args.count() > 1)
            stream << args.last();
        else
            stream << QString();
        stream.flush();
        socket.waitForBytesWritten();
        return;

QDesktopServices::setUrlHandler(QLatin1String("http"), this, "openUrl");

settings.beginGroup(QLatin1String("sessions"));
    m_lastSession = settings.value(QLatin1String("lastSession")).toByteArray();
    settings.endGroup();