[mutter/cherry-pick-c7954be5] tests/wayland/test-driver: Unset resource user data on finalize

[Jonas Ådahl <jadahl src gnome org>]

commit a36fcf6f70e36edceb8366c7a8096cb90d335020
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Sep 1 09:37:17 2022 +0200

    tests/wayland/test-driver: Unset resource user data on finalize
    
    Client connections may linger after the test driver is teared down;
    handle this gracefully by unsetting the user data on the wl_resource,
    and make the resource destructor a no-op, instead of where it would
    otherwise remove itself from the resource list. This fixes this crash
    seen in CI:
    
    Received signal 11 (SIGSEGV)
     #0  g_list_remove() at ../glib/glist.c:596
     #1  test_driver_destructor() at ../src/tests/meta-wayland-test-driver.c:219
     #2  destroy_resource() at ../src/wayland-server.c:730
     #3  for_each_helper() at ../src/wayland-util.c:416
     #4  wl_map_for_each() at ../src/wayland-util.c:430
     #5  wl_client_destroy() at ../src/wayland-server.c:889
     #6  wl_display_destroy_clients() at ../src/wayland-server.c:1482
     #7  meta_wayland_compositor_prepare_shutdown() at ../src/wayland/meta-wayland.c:441
     #8  meta_context_dispose() at ../src/core/meta-context.c:667
     #9  g_object_unref() at ../gobject/gobject.c:3863
     #9  g_object_unref() at ../gobject/gobject.c:3780
     #10 glib_autoptr_clear_GObject() at /usr/include/glib-2.0/gobject/gobject-autocleanups.h:29
     #10 glib_autoptr_clear_MetaContext() at ../src/meta/meta-context.h:32
     #10 glib_autoptr_cleanup_MetaContext() at ../src/meta/meta-context.h:32
     #10 main() at ../src/tests/wayland-unit-tests.c:707
     #11 __libc_start_call_main() in /usr/lib64/libc.so.6
     #12 __libc_start_main() in /usr/lib64/libc.so.6
     #13 _start() in /builds/GNOME/mutter/build/src/tests/mutter-wayland-unit
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2601>
    
    
    (cherry picked from commit c7954be56edec947f3b649ce88420214bf9d4961)

 src/tests/meta-wayland-test-driver.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)
---
diff --git a/src/tests/meta-wayland-test-driver.c b/src/tests/meta-wayland-test-driver.c
index e8413e0b85..c88f66b7ff 100644
--- a/src/tests/meta-wayland-test-driver.c
+++ b/src/tests/meta-wayland-test-driver.c
@@ -102,7 +102,11 @@ static const struct test_driver_interface meta_test_driver_interface = {
 static void
 test_driver_destructor (struct wl_resource *resource)
 {
-  MetaWaylandTestDriver *test_driver = wl_resource_get_user_data (resource);
+  MetaWaylandTestDriver *test_driver;
+
+  test_driver = wl_resource_get_user_data (resource);
+  if (!test_driver)
+    return;
 
   test_driver->resources = g_list_remove (test_driver->resources, resource);
 }
@@ -128,6 +132,15 @@ static void
 meta_wayland_test_driver_finalize (GObject *object)
 {
   MetaWaylandTestDriver *test_driver = META_WAYLAND_TEST_DRIVER (object);
+  GList *l;
+
+  for (l = test_driver->resources; l; l = l->next)
+    {
+      struct wl_resource *resource = l->data;
+
+      wl_resource_set_user_data (resource, NULL);
+    }
+  g_clear_list (&test_driver->resources, NULL);
 
   g_clear_pointer (&test_driver->test_driver, wl_global_destroy);