stage-manager: Use macros for subclassing boilerplate

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3387>

clutter/clutter/clutter-stage-manager-private.h

@@ -28,13 +28,6 @@
 
 G_BEGIN_DECLS
 
-struct _ClutterStageManager
-{
-  GObject parent_instance;
-
-  GSList *stages;
-};
-
 /* stage manager */
 void _clutter_stage_manager_add_stage         (ClutterStageManager *stage_manager,
                                                ClutterStage        *stage);

clutter/clutter/clutter-stage-manager.c

@@ -61,7 +61,14 @@ enum
 static guint manager_signals[LAST_SIGNAL] = { 0, };
 static ClutterStage *default_stage = NULL;
 
-G_DEFINE_TYPE (ClutterStageManager, clutter_stage_manager, G_TYPE_OBJECT);
+typedef struct _ClutterStageManagerPrivate
+{
+  GSList *stages;
+} ClutterStageManagerPrivate;
+
+G_DEFINE_TYPE_WITH_PRIVATE (ClutterStageManager,
+                            clutter_stage_manager,
+                            G_TYPE_OBJECT);
 
 static void
 clutter_stage_manager_get_property (GObject    *gobject,
@@ -83,13 +90,13 @@ clutter_stage_manager_get_property (GObject    *gobject,
 static void
 clutter_stage_manager_dispose (GObject *gobject)
 {
-  ClutterStageManager *stage_manager;
+  ClutterStageManager *stage_manager = CLUTTER_STAGE_MANAGER (gobject);
+  ClutterStageManagerPrivate *priv =
+    clutter_stage_manager_get_instance_private (stage_manager);
 
-  stage_manager = CLUTTER_STAGE_MANAGER (gobject);
+  g_slist_free_full (priv->stages,
-
-  g_slist_free_full (stage_manager->stages,
                      (GDestroyNotify) clutter_actor_destroy);
-  stage_manager->stages = NULL;
+  priv->stages = NULL;
 
   G_OBJECT_CLASS (clutter_stage_manager_parent_class)->dispose (gobject);
 }
@@ -200,7 +207,10 @@ clutter_stage_manager_get_default_stage (ClutterStageManager *stage_manager)
 GSList *
 clutter_stage_manager_list_stages (ClutterStageManager *stage_manager)
 {
-  return g_slist_copy (stage_manager->stages);
+  ClutterStageManagerPrivate *priv =
+    clutter_stage_manager_get_instance_private (stage_manager);
+
+  return g_slist_copy (priv->stages);
 }
 
 /**
@@ -217,14 +227,19 @@ clutter_stage_manager_list_stages (ClutterStageManager *stage_manager)
 const GSList *
 clutter_stage_manager_peek_stages (ClutterStageManager *stage_manager)
 {
-  return stage_manager->stages;
+  ClutterStageManagerPrivate *priv =
+    clutter_stage_manager_get_instance_private (stage_manager);
+
+  return priv->stages;
 }
 
 void
 _clutter_stage_manager_add_stage (ClutterStageManager *stage_manager,
                                   ClutterStage        *stage)
 {
-  if (g_slist_find (stage_manager->stages, stage))
+  ClutterStageManagerPrivate *priv =
+    clutter_stage_manager_get_instance_private (stage_manager);
+  if (g_slist_find (priv->stages, stage))
     {
       g_warning ("Trying to add a stage to the list of managed stages, "
                  "but it is already in it, aborting.");
@@ -233,7 +248,7 @@ _clutter_stage_manager_add_stage (ClutterStageManager *stage_manager,
 
   g_object_ref_sink (stage);
 
-  stage_manager->stages = g_slist_append (stage_manager->stages, stage);
+  priv->stages = g_slist_append (priv->stages, stage);
 
   g_signal_emit (stage_manager, manager_signals[STAGE_ADDED], 0, stage);
 }
@@ -242,13 +257,15 @@ void
 _clutter_stage_manager_remove_stage (ClutterStageManager *stage_manager,
                                      ClutterStage        *stage)
 {
+  ClutterStageManagerPrivate *priv =
+    clutter_stage_manager_get_instance_private (stage_manager);
   /* this might be called multiple times from a ::dispose, so it
    * needs to just return without warning
    */
-  if (!g_slist_find (stage_manager->stages, stage))
+  if (!g_slist_find (priv->stages, stage))
     return;
 
-  stage_manager->stages = g_slist_remove (stage_manager->stages, stage);
+  priv->stages = g_slist_remove (priv->stages, stage);
 
   /* if the default stage is being destroyed then we unset the pointer */
   if (default_stage == stage)

clutter/clutter/clutter-stage-manager.h

@@ -32,14 +32,13 @@
 G_BEGIN_DECLS
 
 #define CLUTTER_TYPE_STAGE_MANAGER              (clutter_stage_manager_get_type ())
-#define CLUTTER_STAGE_MANAGER(obj)              (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_STAGE_MANAGER, ClutterStageManager))
-#define CLUTTER_IS_STAGE_MANAGER(obj)           (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_STAGE_MANAGER))
-#define CLUTTER_STAGE_MANAGER_CLASS(klass)      (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_STAGE_MANAGER, ClutterStageManagerClass))
-#define CLUTTER_IS_STAGE_MANAGER_CLASS(klass)   (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_STAGE_MANAGER))
-#define CLUTTER_STAGE_MANAGER_GET_CLASS(obj)    (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_STAGE_MANAGER, ClutterStageManagerClass))
 
-typedef struct _ClutterStageManager             ClutterStageManager;
+CLUTTER_EXPORT
-typedef struct _ClutterStageManagerClass        ClutterStageManagerClass;
+G_DECLARE_DERIVABLE_TYPE (ClutterStageManager,
+                          clutter_stage_manager,
+                          CLUTTER,
+                          STAGE_MANAGER,
+                          GObject)
 
 /**
  * ClutterStageManagerClass:
@@ -58,9 +57,6 @@ struct _ClutterStageManagerClass
                           ClutterStage        *stage);
 };
 
-CLUTTER_EXPORT
-GType clutter_stage_manager_get_type (void) G_GNUC_CONST;
-
 CLUTTER_EXPORT
 ClutterStageManager *clutter_stage_manager_get_default       (void);
 CLUTTER_EXPORT