backend: Clean up the device manager creation

Create the device manager during the event initialization, where it
makes sense.

This allows us to get rid of the per-backend get_device_manager()
virtual function, and just store the DeviceManager pointer into the
ClutterBackend structure.

clutter/cex100/clutter-backend-cex100.c

@@ -62,24 +62,6 @@ static guint gdl_n_buffers = CLUTTER_CEX100_TRIPLE_BUFFERING;
 
 G_DEFINE_TYPE (ClutterBackendCex100, clutter_backend_cex100, CLUTTER_TYPE_BACKEND);
 
-static ClutterDeviceManager *
-clutter_backend_cex100_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendCex100 *backend_cex100 = CLUTTER_BACKEND_CEX100 (backend);
-
-#ifdef HAVE_EVDEV
-  if (G_UNLIKELY (backend_cex100->device_manager == NULL))
-    {
-      backend_cex100->device_manager =
-	g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_EVDEV,
-		      "backend", backend_cex100,
-		      NULL);
-    }
-#endif /* HAVE_EVDEV */
-
-  return backend_cex100->device_manager;
-}
-
 static void
 clutter_backend_cex100_dispose (GObject *gobject)
 {
@@ -91,12 +73,6 @@ clutter_backend_cex100_dispose (GObject *gobject)
       backend_cex100->event_timer = NULL;
     }
 
-  if (backend_cex100->device_manager != NULL)
-    {
-      g_object_unref (backend_cex100->device_manager);
-      backend_cex100->device_manager = NULL;
-    }
-
   G_OBJECT_CLASS (clutter_backend_cex100_parent_class)->dispose (gobject);
 }
 
@@ -145,7 +121,6 @@ clutter_backend_cex100_class_init (ClutterBackendCex100Class *klass)
 
   backend_class->stage_window_type = CLUTTER_TYPE_STAGE_COGL;
 
-  backend_class->get_device_manager = clutter_backend_cex100_get_device_manager;
   backend_class->get_display = clutter_backend_cex100_get_display;
 }
 

clutter/clutter-backend-private.h

@@ -39,11 +39,13 @@ typedef struct _ClutterBackendPrivate   ClutterBackendPrivate;
 struct _ClutterBackend
 {
   /*< private >*/
-  GObject                parent_instance;
+  GObject parent_instance;
 
-  CoglRenderer          *cogl_renderer;
+  CoglRenderer *cogl_renderer;
-  CoglDisplay           *cogl_display;
+  CoglDisplay *cogl_display;
-  CoglContext           *cogl_context;
+  CoglContext *cogl_context;
+
+  ClutterDeviceManager *device_manager;
 
   ClutterBackendPrivate *priv;
 };

clutter/clutter-backend.c

@@ -504,6 +504,18 @@ clutter_backend_real_init_events (ClutterBackend *backend)
     g_error ("Unknown input backend");
 }
 
+static ClutterDeviceManager *
+clutter_backend_real_get_device_manager (ClutterBackend *backend)
+{
+  if (G_UNLIKELY (backend->device_manager == NULL))
+    {
+      g_critical ("No device manager available, expect broken input");
+      return NULL;
+    }
+
+  return backend->device_manager;
+}
+
 static gboolean
 clutter_backend_real_translate_event (ClutterBackend *backend,
                                       gpointer        native,
@@ -603,6 +615,7 @@ clutter_backend_class_init (ClutterBackendClass *klass)
   klass->font_changed = clutter_backend_real_font_changed;
 
   klass->init_events = clutter_backend_real_init_events;
+  klass->get_device_manager = clutter_backend_real_get_device_manager;
   klass->translate_event = clutter_backend_real_translate_event;
   klass->create_context = clutter_backend_real_create_context;
   klass->ensure_context = clutter_backend_real_ensure_context;

clutter/clutter-device-manager.c

@@ -200,12 +200,9 @@ clutter_device_manager_init (ClutterDeviceManager *self)
 ClutterDeviceManager *
 clutter_device_manager_get_default (void)
 {
-  ClutterBackendClass *klass;
+  ClutterBackend *backend = clutter_get_default_backend ();
 
-  klass = CLUTTER_BACKEND_GET_CLASS (clutter_get_default_backend ());
+  return backend->device_manager;
-  g_assert (klass->get_device_manager != NULL);
-
-  return klass->get_device_manager (clutter_get_default_backend ());
 }
 
 /**

clutter/egl/clutter-backend-eglnative.c

@@ -57,24 +57,6 @@
 
 G_DEFINE_TYPE (ClutterBackendEglNative, clutter_backend_egl_native, CLUTTER_TYPE_BACKEND);
 
-static ClutterDeviceManager *
-clutter_backend_egl_native_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendEglNative *backend_egl_native = CLUTTER_BACKEND_EGL_NATIVE (backend);
-
-#ifdef HAVE_EVDEV
-  if (G_UNLIKELY (backend_egl_native->device_manager == NULL))
-    {
-      backend_egl_native->device_manager =
-	g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_EVDEV,
-		      "backend", backend_egl_native,
-		      NULL);
-    }
-#endif
-
-  return backend_egl_native->device_manager;
-}
-
 static void
 clutter_backend_egl_native_dispose (GObject *gobject)
 {
@@ -86,12 +68,6 @@ clutter_backend_egl_native_dispose (GObject *gobject)
       backend_egl_native->event_timer = NULL;
     }
 
-  if (backend_egl_native->device_manager != NULL)
-    {
-      g_object_unref (backend_egl_native->device_manager);
-      backend_egl_native->device_manager = NULL;
-    }
-
   G_OBJECT_CLASS (clutter_backend_egl_native_parent_class)->dispose (gobject);
 }
 
@@ -104,8 +80,6 @@ clutter_backend_egl_native_class_init (ClutterBackendEglNativeClass *klass)
   gobject_class->dispose = clutter_backend_egl_native_dispose;
 
   backend_class->stage_window_type = CLUTTER_TYPE_STAGE_COGL;
-
-  backend_class->get_device_manager = clutter_backend_egl_native_get_device_manager;
 }
 
 static void

clutter/evdev/clutter-device-manager-evdev.c

@@ -847,20 +847,14 @@ clutter_device_manager_evdev_init (ClutterDeviceManagerEvdev *self)
   self->priv = CLUTTER_DEVICE_MANAGER_EVDEV_GET_PRIVATE (self);
 }
 
-/*
- * _clutter_events_evdev_init() and _clutter_events_evdev_uninit() are the two
- * symbol to use the evdev event backend from the EGL backend
- */
-
 void
 _clutter_events_evdev_init (ClutterBackend *backend)
 {
-  ClutterDeviceManager *dummy G_GNUC_UNUSED;
-
   CLUTTER_NOTE (EVENT, "Initializing evdev backend");
 
-  /* we need to create the device manager here */
+  backend->device_manager = g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_EVDEV,
-  dummy = clutter_device_manager_get_default ();
+                                          "backend", backend,
+                                          NULL);
 }
 
 void

clutter/gdk/clutter-backend-gdk.c

@@ -191,8 +191,16 @@ gdk_event_handler (GdkEvent *event,
 void
 _clutter_backend_gdk_events_init (ClutterBackend *backend)
 {
+  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (backend);
+
   CLUTTER_NOTE (EVENT, "initialising the event loop");
 
+  backend->device_manager =
+    g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_GDK,
+                  "backend", backend,
+                  "gdk-display", backend_gdk->display,
+                  NULL);
+
   if (!disable_event_retrieval)
     gdk_event_handler_set (gdk_event_handler, NULL, NULL);
 }
@@ -249,22 +257,6 @@ clutter_backend_gdk_free_event_data (ClutterBackend *backend,
     gdk_event_free (gdk_event);
 }
 
-static ClutterDeviceManager *
-clutter_backend_gdk_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (backend);
-
-  if (G_UNLIKELY (backend_gdk->device_manager == NULL))
-    {
-      backend_gdk->device_manager = g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_GDK,
-						  "backend", backend_gdk,
-						  "gdk-display", backend_gdk->display,
-						  NULL);
-    }
-
-  return backend_gdk->device_manager;
-}
-
 static CoglRenderer *
 clutter_backend_gdk_get_renderer (ClutterBackend  *backend,
                                   GError         **error)
@@ -381,7 +373,6 @@ clutter_backend_gdk_class_init (ClutterBackendGdkClass *klass)
   backend_class->post_parse = _clutter_backend_gdk_post_parse;
 
   backend_class->get_features = clutter_backend_gdk_get_features;
-  backend_class->get_device_manager = clutter_backend_gdk_get_device_manager;
   backend_class->copy_event_data = clutter_backend_gdk_copy_event_data;
   backend_class->free_event_data = clutter_backend_gdk_free_event_data;
 

clutter/osx/clutter-backend-osx.c

@@ -94,27 +94,6 @@ clutter_backend_osx_create_stage (ClutterBackend  *backend,
   return impl;
 }
 
-static inline void
-clutter_backend_osx_create_device_manager (ClutterBackendOSX *backend_osx)
-{
-  if (backend_osx->device_manager != NULL)
-    return;
-
-  backend_osx->device_manager = g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_OSX,
-                                              "backend", CLUTTER_BACKEND(backend_osx),
-                                              NULL);
-}
-
-static ClutterDeviceManager *
-clutter_backend_osx_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendOSX *backend_osx = CLUTTER_BACKEND_OSX (backend);
-
-  clutter_backend_osx_create_device_manager (backend_osx);
-
-  return backend_osx->device_manager;
-}
-
 void
 _clutter_backend_osx_events_init (ClutterBackend *backend)
 {
@@ -125,7 +104,10 @@ _clutter_backend_osx_events_init (ClutterBackend *backend)
 
   CLUTTER_NOTE (BACKEND, "init_events");
 
-  clutter_backend_osx_create_device_manager (backend_osx);
+  backend->device_manager = backend_osx->device_manager =
+    g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_OSX,
+                  "backend", CLUTTER_BACKEND(backend_osx),
+                  NULL);
 
   _clutter_osx_event_loop_init ();
 }
@@ -256,5 +238,4 @@ clutter_backend_osx_class_init (ClutterBackendOSXClass *klass)
   backend_class->create_stage       = clutter_backend_osx_create_stage;
   backend_class->create_context     = clutter_backend_osx_create_context;
   backend_class->ensure_context     = clutter_backend_osx_ensure_context;
-  backend_class->get_device_manager = clutter_backend_osx_get_device_manager;
 }

clutter/win32/clutter-backend-win32.c

@@ -59,7 +59,7 @@ clutter_backend_win32_init_events (ClutterBackend *backend)
 
   CLUTTER_NOTE (EVENT, "initialising the event loop");
 
-  backend_win32->device_manager =
+  backend->device_manager =
     g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_WIN32,
                   "backend", backend_win32,
                   NULL);
@@ -168,22 +168,6 @@ clutter_backend_win32_get_features (ClutterBackend *backend)
     | CLUTTER_FEATURE_STAGE_CURSOR;
 }
 
-static ClutterDeviceManager *
-clutter_backend_win32_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
-
-  if (G_UNLIKELY (backend_win32->device_manager == NULL))
-    {
-      backend_win32->device_manager =
-        g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_WIN32,
-                      "backend", backend_win32,
-                      NULL);
-    }
-
-  return backend_win32->device_manager;
-}
-
 /**
  * clutter_win32_disable_event_retrieval
  *
@@ -222,7 +206,6 @@ clutter_backend_win32_class_init (ClutterBackendWin32Class *klass)
   backend_class->init_events = clutter_backend_win32_init_events;
   backend_class->add_options = clutter_backend_win32_add_options;
   backend_class->get_features = clutter_backend_win32_get_features;
-  backend_class->get_device_manager = clutter_backend_win32_get_device_manager;
 }
 
 static void

clutter/x11/clutter-backend-x11.c

@@ -277,6 +277,8 @@ clutter_backend_x11_create_device_manager (ClutterBackendX11 *backend_x11)
         }
 
       backend = CLUTTER_BACKEND (backend_x11);
+      backend->device_manager = backend_x11->device_manager;
+
       translator = CLUTTER_EVENT_TRANSLATOR (backend_x11->device_manager);
       _clutter_backend_add_event_translator (backend, translator);
     }
@@ -589,16 +591,6 @@ clutter_backend_x11_free_event_data (ClutterBackend *backend,
     _clutter_event_x11_free (event_x11);
 }
 
-static ClutterDeviceManager *
-clutter_backend_x11_get_device_manager (ClutterBackend *backend)
-{
-  ClutterBackendX11 *backend_x11 = CLUTTER_BACKEND_X11 (backend);
-
-  clutter_backend_x11_create_device_manager (backend_x11);
-
-  return backend_x11->device_manager;
-}
-
 static void
 update_last_event_time (ClutterBackendX11 *backend_x11,
                         XEvent            *xevent)
@@ -815,7 +807,6 @@ clutter_backend_x11_class_init (ClutterBackendX11Class *klass)
   backend_class->add_options = clutter_backend_x11_add_options;
   backend_class->get_features = clutter_backend_x11_get_features;
 
-  backend_class->get_device_manager = clutter_backend_x11_get_device_manager;
   backend_class->copy_event_data = clutter_backend_x11_copy_event_data;
   backend_class->free_event_data = clutter_backend_x11_free_event_data;
   backend_class->translate_event = clutter_backend_x11_translate_event;