dbus-session: Make some properties part of the interface

The pointer to the manager, the peer name and the ID are things that are
always metadata related to a session, so make them properties on the
interface instead of duplicating them. The implementations still need to
keep track of them, but their existance is shared.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2713>

src/backends/meta-dbus-session-manager.c

@@ -288,7 +288,7 @@ on_session_closed (MetaDbusSession        *session,
 {
   MetaDbusSessionManagerPrivate *priv =
     meta_dbus_session_manager_get_instance_private (session_manager);
-  const char *session_id;
+  g_autofree char *session_id = NULL;
 
   session_id = meta_dbus_session_get_id (session);
   g_hash_table_remove (priv->sessions, session_id);

src/backends/meta-dbus-session-watcher.c

@@ -26,6 +26,8 @@
 
 #include <gio/gio.h>
 
+#include "backends/meta-dbus-session-manager.h"
+
 enum
 {
   SESSION_SIGNAL_SESSION_CLOSED,
@@ -186,9 +188,52 @@ meta_dbus_session_notify_closed (MetaDbusSession *session)
   g_signal_emit (session, session_signals[SESSION_SIGNAL_SESSION_CLOSED], 0);
 }
 
+void
+meta_dbus_session_install_properties (GObjectClass *object_class,
+                                      unsigned int  first_prop)
+{
+  g_object_class_override_property (object_class,
+                                    first_prop + META_DBUS_SESSION_PROP_SESSION_MANAGER,
+                                    "session-manager");
+  g_object_class_override_property (object_class,
+                                    first_prop + META_DBUS_SESSION_PROP_PEER_NAME,
+                                    "peer-name");
+  g_object_class_override_property (object_class,
+                                    first_prop + META_DBUS_SESSION_PROP_ID,
+                                    "id");
+}
+
 static void
 meta_dbus_session_default_init (MetaDbusSessionInterface *iface)
 {
+  g_object_interface_install_property (
+    iface,
+    g_param_spec_object ("session-manager",
+                         "session manager",
+                         "D-Bus session manager",
+                         META_TYPE_DBUS_SESSION_MANAGER,
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY |
+                         G_PARAM_STATIC_STRINGS));
+  g_object_interface_install_property (
+    iface,
+    g_param_spec_string ("peer-name",
+                         "peer name",
+                         "D-Bus peer name",
+                         NULL,
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY |
+                         G_PARAM_STATIC_STRINGS));
+  g_object_interface_install_property (
+    iface,
+    g_param_spec_string ("id",
+                         "session id",
+                         "Unique ID of the session",
+                         NULL,
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY |
+                         G_PARAM_STATIC_STRINGS));
+
   session_signals[SESSION_SIGNAL_SESSION_CLOSED] =
     g_signal_new ("session-closed",
                   G_TYPE_FROM_INTERFACE (iface),
@@ -232,8 +277,32 @@ meta_dbus_session_close (MetaDbusSession *session)
   META_DBUS_SESSION_GET_IFACE (session)->close (session);
 }
 
-const char *
+MetaDbusSessionManager *
+meta_dbus_session_manager (MetaDbusSessionManager *session)
+{
+  MetaDbusSessionManager *manager;
+
+  g_object_get (session, "session-manager", &manager, NULL);
+
+  return manager;
+}
+
+char *
+meta_dbus_session_get_peer_name (MetaDbusSession *session)
+{
+  char *peer_name;
+
+  g_object_get (session, "peer-name", &peer_name, NULL);
+
+  return peer_name;
+}
+
+char *
 meta_dbus_session_get_id (MetaDbusSession *session)
 {
-  return META_DBUS_SESSION_GET_IFACE (session)->get_id (session);
+  char *id;
+
+  g_object_get (session, "id", &id, NULL);
+
+  return id;
 }

src/backends/meta-dbus-session-watcher.h

@@ -25,6 +25,15 @@
 
 #include <glib-object.h>
 
+#include "backends/meta-backend-types.h"
+
+enum
+{
+  META_DBUS_SESSION_PROP_SESSION_MANAGER,
+  META_DBUS_SESSION_PROP_PEER_NAME,
+  META_DBUS_SESSION_PROP_ID,
+};
+
 #define META_TYPE_DBUS_SESSION (meta_dbus_session_get_type ())
 G_DECLARE_INTERFACE (MetaDbusSession, meta_dbus_session,
                      META, DBUS_SESSION,
@@ -35,7 +44,6 @@ struct _MetaDbusSessionInterface
   GTypeInterface parent_iface;
 
   void (* close) (MetaDbusSession *session);
-  const char * (* get_id) (MetaDbusSession *session);
 };
 
 #define META_TYPE_DBUS_SESSION_WATCHER (meta_dbus_session_watcher_get_type ())
@@ -48,10 +56,17 @@ void meta_dbus_session_watcher_watch_session (MetaDbusSessionWatcher *session_wa
                                               const char             *client_dbus_name,
                                               MetaDbusSession        *session);
 
+void meta_dbus_session_install_properties (GObjectClass *object_class,
+                                           unsigned int  first_prop);
+
 void meta_dbus_session_notify_closed (MetaDbusSession *session);
 
 void meta_dbus_session_close (MetaDbusSession *session);
 
-const char * meta_dbus_session_get_id (MetaDbusSession *session);
+MetaDbusSessionManager * meta_dbus_session_manager (MetaDbusSessionManager *session);
+
+char * meta_dbus_session_get_peer_name (MetaDbusSession *session);
+
+char * meta_dbus_session_get_id (MetaDbusSession *session);
 
 #endif /* META_DBUS_SESSION_WATCHER_H */

src/backends/meta-remote-desktop-session.c

@@ -54,15 +54,9 @@ enum
 {
   PROP_0,
 
-  PROP_SESSION_MANAGER,
-  PROP_PEER_NAME,
-  PROP_ID,
-
   N_PROPS
 };
 
-static GParamSpec *obj_props[N_PROPS];
-
 typedef enum _MetaRemoteDesktopNotifyAxisFlags
 {
   META_REMOTE_DESKTOP_NOTIFY_AXIS_FLAGS_NONE = 0,
@@ -265,14 +259,6 @@ meta_remote_desktop_session_close (MetaDbusSession *dbus_session)
   g_object_unref (session);
 }
 
-static const char *
-meta_remote_desktop_session_get_id (MetaDbusSession *dbus_session)
-{
-  MetaRemoteDesktopSession *session = META_REMOTE_DESKTOP_SESSION (dbus_session);
-
-  return session->session_id;
-}
-
 char *
 meta_remote_desktop_session_get_object_path (MetaRemoteDesktopSession *session)
 {
@@ -1706,7 +1692,6 @@ static void
 meta_dbus_session_init_iface (MetaDbusSessionInterface *iface)
 {
   iface->close = meta_remote_desktop_session_close;
-  iface->get_id = meta_remote_desktop_session_get_id;
 }
 
 static void
@@ -1741,13 +1726,13 @@ meta_remote_desktop_session_set_property (GObject      *object,
 
   switch (prop_id)
     {
-    case PROP_SESSION_MANAGER:
+    case N_PROPS + META_DBUS_SESSION_PROP_SESSION_MANAGER:
       session->session_manager = g_value_get_object (value);
       break;
-    case PROP_PEER_NAME:
+    case N_PROPS + META_DBUS_SESSION_PROP_PEER_NAME:
       session->peer_name = g_value_dup_string (value);
       break;
-    case PROP_ID:
+    case N_PROPS + META_DBUS_SESSION_PROP_ID:
       session->session_id = g_value_dup_string (value);
       break;
     default:
@@ -1766,13 +1751,13 @@ meta_remote_desktop_session_get_property (GObject    *object,
 
   switch (prop_id)
     {
-    case PROP_SESSION_MANAGER:
+    case N_PROPS + META_DBUS_SESSION_PROP_SESSION_MANAGER:
       g_value_set_object (value, session->session_manager);
       break;
-    case PROP_PEER_NAME:
+    case N_PROPS + META_DBUS_SESSION_PROP_PEER_NAME:
       g_value_set_string (value, session->peer_name);
       break;
-    case PROP_ID:
+    case N_PROPS + META_DBUS_SESSION_PROP_ID:
       g_value_set_string (value, session->session_id);
       break;
     default:
@@ -1803,31 +1788,7 @@ meta_remote_desktop_session_class_init (MetaRemoteDesktopSessionClass *klass)
   object_class->set_property = meta_remote_desktop_session_set_property;
   object_class->get_property = meta_remote_desktop_session_get_property;
 
-  obj_props[PROP_SESSION_MANAGER] =
+  meta_dbus_session_install_properties (object_class, N_PROPS);
-    g_param_spec_object ("session-manager",
-                         "session manager",
-                         "D-Bus session manager",
-                         META_TYPE_DBUS_SESSION_MANAGER,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_PEER_NAME] =
-    g_param_spec_string ("peer-name",
-                         "peer name",
-                         "D-Bus peer name",
-                         NULL,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_ID] =
-    g_param_spec_string ("id",
-                         "session id",
-                         "Unique ID of the session",
-                         NULL,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
-  g_object_class_install_properties (object_class, N_PROPS, obj_props);
 }
 
 static MetaRemoteDesktopSessionHandle *

src/backends/meta-screen-cast-session.c

@@ -43,9 +43,6 @@ enum
 {
   PROP_0,
 
-  PROP_SESSION_MANAGER,
-  PROP_PEER_NAME,
-  PROP_ID,
   PROP_SESSION_TYPE,
 
   N_PROPS
@@ -186,14 +183,6 @@ meta_screen_cast_session_close (MetaDbusSession *dbus_session)
   g_object_unref (session);
 }
 
-static const char *
-meta_screen_cast_session_get_id (MetaDbusSession *dbus_session)
-{
-  MetaScreenCastSession *session = META_SCREEN_CAST_SESSION (dbus_session);
-
-  return session->session_id;
-}
-
 MetaScreenCastStream *
 meta_screen_cast_session_get_stream (MetaScreenCastSession *session,
                                      const char            *path)
@@ -777,7 +766,6 @@ static void
 meta_dbus_session_init_iface (MetaDbusSessionInterface *iface)
 {
   iface->close = meta_screen_cast_session_close;
-  iface->get_id = meta_screen_cast_session_get_id;
 }
 
 static void
@@ -803,18 +791,19 @@ meta_screen_cast_session_set_property (GObject      *object,
 
   switch (prop_id)
     {
-    case PROP_SESSION_MANAGER:
-      session->session_manager = g_value_get_object (value);
-      break;
-    case PROP_PEER_NAME:
-      session->peer_name = g_value_dup_string (value);
-      break;
-    case PROP_ID:
-      session->session_id = g_value_dup_string (value);
-      break;
     case PROP_SESSION_TYPE:
       session->session_type = g_value_get_enum (value);
       break;
+
+    case N_PROPS + META_DBUS_SESSION_PROP_SESSION_MANAGER:
+      session->session_manager = g_value_get_object (value);
+      break;
+    case N_PROPS + META_DBUS_SESSION_PROP_PEER_NAME:
+      session->peer_name = g_value_dup_string (value);
+      break;
+    case N_PROPS + META_DBUS_SESSION_PROP_ID:
+      session->session_id = g_value_dup_string (value);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -831,18 +820,19 @@ meta_screen_cast_session_get_property (GObject    *object,
 
   switch (prop_id)
     {
-    case PROP_SESSION_MANAGER:
-      g_value_set_object (value, session->session_manager);
-      break;
-    case PROP_PEER_NAME:
-      g_value_set_string (value, session->peer_name);
-      break;
-    case PROP_ID:
-      g_value_set_string (value, session->session_id);
-      break;
     case PROP_SESSION_TYPE:
       g_value_set_enum (value, session->session_type);
       break;
+
+    case N_PROPS + META_DBUS_SESSION_PROP_SESSION_MANAGER:
+      g_value_set_object (value, session->session_manager);
+      break;
+    case N_PROPS + META_DBUS_SESSION_PROP_PEER_NAME:
+      g_value_set_string (value, session->peer_name);
+      break;
+    case N_PROPS + META_DBUS_SESSION_PROP_ID:
+      g_value_set_string (value, session->session_id);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -863,30 +853,6 @@ meta_screen_cast_session_class_init (MetaScreenCastSessionClass *klass)
   object_class->set_property = meta_screen_cast_session_set_property;
   object_class->get_property = meta_screen_cast_session_get_property;
 
-  obj_props[PROP_SESSION_MANAGER] =
-    g_param_spec_object ("session-manager",
-                         "session manager",
-                         "D-Bus session manager",
-                         META_TYPE_DBUS_SESSION_MANAGER,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_PEER_NAME] =
-    g_param_spec_string ("peer-name",
-                         "peer name",
-                         "D-Bus peer name",
-                         NULL,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_ID] =
-    g_param_spec_string ("id",
-                         "session id",
-                         "Unique ID of the session",
-                         NULL,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
   obj_props[PROP_SESSION_TYPE] =
     g_param_spec_enum ("session-type",
                        "session type",
@@ -897,6 +863,7 @@ meta_screen_cast_session_class_init (MetaScreenCastSessionClass *klass)
                        G_PARAM_CONSTRUCT_ONLY |
                        G_PARAM_STATIC_STRINGS);
   g_object_class_install_properties (object_class, N_PROPS, obj_props);
+  meta_dbus_session_install_properties (object_class, N_PROPS);
 }
 
 static gboolean