[mutter/gnome-3-26] wayland-outputs: Delay wl_output destruction

[Rui Matos <rtcm src gnome org>]

commit cde5454622d99320a66f2fd352df132a4bfdab4b
Author: Rui Matos <tiagomatos gmail com>
Date:   Wed Dec 6 17:05:02 2017 +0100

    wayland-outputs: Delay wl_output destruction
    
    This tries to avoid wayland clients getting disconnected for binding
    to a wl_output that we already destroyed which is a known protocol
    race condition, see https://phabricator.freedesktop.org/T7722 .
    
    https://bugzilla.gnome.org/show_bug.cgi?id=789070

 src/wayland/meta-wayland-outputs.c |   23 ++++++++++++++++++++++-
 1 files changed, 22 insertions(+), 1 deletions(-)
---
diff --git a/src/wayland/meta-wayland-outputs.c b/src/wayland/meta-wayland-outputs.c
index 51f62f9..4dfdb18 100644
--- a/src/wayland/meta-wayland-outputs.c
+++ b/src/wayland/meta-wayland-outputs.c
@@ -244,6 +244,9 @@ bind_output (struct wl_client *client,
   wl_resource_set_user_data (resource, wayland_output);
   wl_resource_set_destructor (resource, output_resource_destroy);
 
+  if (!logical_monitor)
+    return;
+
   monitor = pick_main_monitor (logical_monitor);
 
   meta_verbose ("Binding monitor %p/%s (%u, %u, %u, %u) x %f\n",
@@ -322,6 +325,22 @@ meta_wayland_output_new (MetaWaylandCompositor *compositor,
   return wayland_output;
 }
 
+static void
+nullify_logical_monitor (gpointer key,
+                         gpointer value,
+                         gpointer data)
+{
+  MetaWaylandOutput *wayland_output = value;
+  wayland_output->logical_monitor = NULL;
+}
+
+static gboolean
+delayed_destroy_outputs (gpointer data)
+{
+  g_hash_table_destroy (data);
+  return G_SOURCE_REMOVE;
+}
+
 static GHashTable *
 meta_wayland_compositor_update_outputs (MetaWaylandCompositor *compositor,
                                         MetaMonitorManager    *monitor_manager)
@@ -362,7 +381,9 @@ meta_wayland_compositor_update_outputs (MetaWaylandCompositor *compositor,
                            wayland_output);
     }
 
-  g_hash_table_destroy (compositor->outputs);
+  g_hash_table_foreach (compositor->outputs, nullify_logical_monitor, NULL);
+  g_timeout_add_seconds (10, delayed_destroy_outputs, compositor->outputs);
+
   return new_table;
 }