[mutter] wayland-surface: disconnect signals on destroy

[Giovanni Campagna <gcampagna src gnome org>]

commit a4f763ac3b0530fd602eb30396abe7147cc4c741
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Tue Oct 13 21:33:15 2015 -0700

    wayland-surface: disconnect signals on destroy
    
    Otherwise signal handlers will be called on garbage
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756548

 src/wayland/meta-wayland-surface.c |   33 ++++++++++++++++++++++-----------
 src/wayland/meta-wayland-surface.h |    2 +-
 2 files changed, 23 insertions(+), 12 deletions(-)
---
diff --git a/src/wayland/meta-wayland-surface.c b/src/wayland/meta-wayland-surface.c
index 9d15401..f8f6ffc 100644
--- a/src/wayland/meta-wayland-surface.c
+++ b/src/wayland/meta-wayland-surface.c
@@ -933,22 +933,26 @@ set_surface_is_on_output (MetaWaylandSurface *surface,
                           MetaWaylandOutput *wayland_output,
                           gboolean is_on_output)
 {
-  gboolean was_on_output = g_hash_table_contains (surface->outputs,
-                                                  wayland_output);
+  gpointer orig_id;
+  gboolean was_on_output = g_hash_table_lookup_extended (surface->outputs_to_destroy_notify_id,
+                                                         wayland_output,
+                                                         NULL, &orig_id);
 
   if (!was_on_output && is_on_output)
     {
-      g_signal_connect (wayland_output, "output-destroyed",
-                        G_CALLBACK (surface_handle_output_destroy),
-                        surface);
-      g_hash_table_add (surface->outputs, wayland_output);
+      gulong id;
+
+      id = g_signal_connect (wayland_output, "output-destroyed",
+                             G_CALLBACK (surface_handle_output_destroy),
+                             surface);
+      g_hash_table_insert (surface->outputs_to_destroy_notify_id, wayland_output,
+                           GSIZE_TO_POINTER ((gsize)id));
       surface_entered_output (surface, wayland_output);
     }
   else if (was_on_output && !is_on_output)
     {
-      g_hash_table_remove (surface->outputs, wayland_output);
-      g_signal_handlers_disconnect_by_func  (
-        wayland_output, (gpointer)surface_handle_output_destroy, surface);
+      g_hash_table_remove (surface->outputs_to_destroy_notify_id, wayland_output);
+      g_signal_handler_disconnect (wayland_output, (gulong) GPOINTER_TO_SIZE (orig_id));
       surface_left_output (surface, wayland_output);
     }
 }
@@ -986,6 +990,12 @@ update_surface_output_state (gpointer key, gpointer value, gpointer user_data)
   set_surface_is_on_output (surface, wayland_output, is_on_output);
 }
 
+static void
+surface_output_disconnect_signal (gpointer key, gpointer value, gpointer user_data)
+{
+  g_signal_handler_disconnect (key, (gulong) GPOINTER_TO_SIZE (value));
+}
+
 void
 meta_wayland_surface_update_outputs (MetaWaylandSurface *surface)
 {
@@ -1036,7 +1046,8 @@ wl_surface_destructor (struct wl_resource *resource)
 
   meta_wayland_compositor_destroy_frame_callbacks (compositor, surface);
 
-  g_hash_table_unref (surface->outputs);
+  g_hash_table_foreach (surface->outputs_to_destroy_notify_id, surface_output_disconnect_signal, surface);
+  g_hash_table_unref (surface->outputs_to_destroy_notify_id);
 
   wl_list_for_each_safe (cb, next, &surface->pending_frame_callback_list, link)
     wl_resource_destroy (cb->resource);
@@ -1081,7 +1092,7 @@ meta_wayland_surface_create (MetaWaylandCompositor *compositor,
 
   sync_drag_dest_funcs (surface);
 
-  surface->outputs = g_hash_table_new (NULL, NULL);
+  surface->outputs_to_destroy_notify_id = g_hash_table_new (NULL, NULL);
 
   pending_state_init (&surface->pending);
   return surface;
diff --git a/src/wayland/meta-wayland-surface.h b/src/wayland/meta-wayland-surface.h
index c0ce8fd..94ba100 100644
--- a/src/wayland/meta-wayland-surface.h
+++ b/src/wayland/meta-wayland-surface.h
@@ -147,7 +147,7 @@ struct _MetaWaylandSurface
   int scale;
   int32_t offset_x, offset_y;
   GList *subsurfaces;
-  GHashTable *outputs;
+  GHashTable *outputs_to_destroy_notify_id;
 
   /* List of pending frame callbacks that needs to stay queued longer than one
    * commit sequence, such as when it has not yet been assigned a role.