Application does not exit after mpv_set_wakeup_callback

[Aario]

Hi Folks,
Thanks for reading this post. I'm developing an application based on libmpv. I use the function mpv_set_wakeup_callback() to set a callback function for mpv events. This will open a separate thread. That's all I know. When MainWindow is closed, the application remains in memory until killed forecfully. I have no idea how to close all threads. I have tried mpv_terminate_destroy but still the same. Any idea is highly appreciated. Thanks in advance.

[jsulm]

@Aario This is Qt forum: is your question somehow related to Qt?

[Aario]

Yes. The problem was with Qt internals conflicting with mpv library's way of multi threading. I have solved the problem by using a QT alternative to mpv_set_wakeup_callback. My solution is available at:
https://github.com/aario/qtible/blob/main/mediaplayer/mpveventloop.cpp

void MPVEventLoop::eventLoop()
{
    qInfo() << "Started event loop";
    while (1) {
        if (mustShutdown)
            break;

        mpv_event *event = mpv_wait_event(mpv, 0.01);

        switch (event->event_id) {
        case MPV_EVENT_NONE:
            break;
        case MPV_EVENT_FILE_LOADED:
            emit fileLoaded();
            break;
        case MPV_EVENT_END_FILE:
            emit endFile();
            break;
        case MPV_EVENT_PROPERTY_CHANGE: {
            mpv_event_property *property = (mpv_event_property *)event->data;
            if (strcmp(property->name, "time-pos") == 0) {
                if (property->format == MPV_FORMAT_DOUBLE) {
                    emit timePosChanged(*(double *)property->data);
                }
            }
            break;
        }
        default: qDebug() << "Ignoring MPV event: " << event->event_id;
        }
    }
}

And then:

    mpvEventLoop = new MPVEventLoop(mpv);
    mpvEventLoop->moveToThread(&mpvEventLoopThread);
    connect(&mpvEventLoopThread, &QThread::finished, mpvEventLoop, &QObject::deleteLater);
    connect(this, &MediaPlayer::startMPVEventLoop, mpvEventLoop, &MPVEventLoop::eventLoop);
    connect(mpvEventLoop, &MPVEventLoop::fileLoaded, this, &MediaPlayer::onMpvFileLoaded);
    connect(mpvEventLoop, &MPVEventLoop::endFile, this, &MediaPlayer::onMpvEndFile);
    connect(mpvEventLoop, &MPVEventLoop::timePosChanged, this, &MediaPlayer::onMpvTimePosChanged);
    mpvEventLoopThread.start();
    emit startMPVEventLoop();