From 90a00dae9938c092d9ef520dabcc2d35dbda0dc6 Mon Sep 17 00:00:00 2001
From: Carlos Garnacho <carlosg@gnome.org>
Date: Wed, 16 Aug 2023 13:46:05 +0200
Subject: [PATCH] compositor: Handle grab state through
 ClutterStage::is-grabbed handler

This is something the compositor could now track by itself, instead of
being pushed through events. It also makes more sense to do this directly
when the grabbing conditions change, as opposed to the next event.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3185>
---
 src/compositor/compositor.c | 18 ++++++++++++++++++
 src/core/display-private.h  |  1 -
 src/core/events.c           | 14 --------------
 3 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/src/compositor/compositor.c b/src/compositor/compositor.c
index 6b45ee91b..69cc2b782 100644
--- a/src/compositor/compositor.c
+++ b/src/compositor/compositor.c
@@ -115,6 +115,7 @@ typedef struct _MetaCompositorPrivate
   gulong after_paint_handler_id;
   gulong window_visibility_updated_id;
   gulong monitors_changed_internal_id;
+  gulong grabbed_notify_handler_id;
 
   int64_t server_time_query_time;
   int64_t server_time_offset;
@@ -1179,6 +1180,17 @@ on_monitors_changed_internal (MetaMonitorManager *monitor_manager,
   meta_compositor_ensure_compositor_views (compositor);
 }
 
+static void
+on_is_grabbed_changed_cb (ClutterStage   *stage,
+                          GParamSpec     *pspec,
+                          MetaCompositor *compositor)
+{
+  if (clutter_stage_get_grab_actor (stage) != NULL)
+    meta_compositor_grab_begin (compositor);
+  else
+    meta_compositor_grab_end (compositor);
+}
+
 static void
 meta_compositor_set_property (GObject      *object,
                               guint         prop_id,
@@ -1255,6 +1267,11 @@ meta_compositor_constructed (GObject *object)
                             "after-paint",
                             G_CALLBACK (on_after_paint),
                             compositor);
+  priv->grabbed_notify_handler_id =
+    g_signal_connect (stage,
+                      "notify::is-grabbed",
+                      G_CALLBACK (on_is_grabbed_changed_cb),
+                      compositor);
 
   priv->window_visibility_updated_id =
     g_signal_connect (priv->display,
@@ -1288,6 +1305,7 @@ meta_compositor_dispose (GObject *object)
   g_clear_signal_handler (&priv->stage_presented_id, stage);
   g_clear_signal_handler (&priv->before_paint_handler_id, stage);
   g_clear_signal_handler (&priv->after_paint_handler_id, stage);
+  g_clear_signal_handler (&priv->grabbed_notify_handler_id, stage);
   g_clear_signal_handler (&priv->window_visibility_updated_id, priv->display);
 
   g_clear_pointer (&priv->windows, g_list_free);
diff --git a/src/core/display-private.h b/src/core/display-private.h
index 4afd0d5df..e847e40e6 100644
--- a/src/core/display-private.h
+++ b/src/core/display-private.h
@@ -120,7 +120,6 @@ struct _MetaDisplay
 
   /* Opening the display */
   unsigned int display_opening : 1;
-  unsigned int grabbed_in_clutter : 1;
 
   /* Closing down the display */
   int closing;
diff --git a/src/core/events.c b/src/core/events.c
index 3a60ee015..7ee03cf37 100644
--- a/src/core/events.c
+++ b/src/core/events.c
@@ -257,20 +257,6 @@ meta_display_handle_event (MetaDisplay        *display,
 
   has_grab = stage_has_grab (display);
 
-  if (display->grabbed_in_clutter != has_grab)
-    {
-      if (!display->grabbed_in_clutter && has_grab)
-        {
-          display->grabbed_in_clutter = TRUE;
-          meta_compositor_grab_begin (compositor);
-        }
-      else if (display->grabbed_in_clutter && !has_grab)
-        {
-          display->grabbed_in_clutter = FALSE;
-          meta_compositor_grab_end (compositor);
-        }
-    }
-
   sequence = clutter_event_get_event_sequence (event);
   event_type = clutter_event_type (event);
   time_ms = clutter_event_get_time (event);