Do not use the default GMainContext

[gnome-mpv]

Using the default GMainContext may cause deadlocks when mpv-mpris is loaded in an mpv frontend that use GLib. See https://github.com/celluloid-player/celluloid/issues/486 for an example of this happening in Celluloid.

Minimal reproducer:

// Build with: gcc `pkg-config --cflags --libs glib-2.0 mpv` test.c  -o test

#include <glib.h>
#include <stdio.h>
#include <mpv/client.h>

struct UserData
{
    mpv_handle *mpv;
    GMainLoop *loop;
};

gboolean
handle_timeout(struct UserData *user_data)
{
    mpv_terminate_destroy(user_data->mpv);
    g_main_loop_quit(user_data->loop);

    return G_SOURCE_REMOVE;
}

int
main(int argc, char **argv)
{
    mpv_handle *mpv = mpv_create();
    mpv_initialize(mpv);
    mpv_command_string(mpv, "load-script ./mpris.so");

    GMainLoop *loop = g_main_loop_new(NULL, FALSE);

    struct UserData user_data = {.mpv = mpv, .loop = loop};
    g_timeout_add(1000, G_SOURCE_FUNC(handle_timeout), &user_data);

    puts("Quitting in 1 second...");
    g_main_loop_run(loop);

    g_main_loop_unref(loop);

    return 0;
}

[hoyon]

Thanks!