[tracker/tracker-0.6] Add mechanisms to TrackerDBInterface/TrackerDBManager to invalidate interfaces.

[Carlos Garnacho <carlosg src gnome org>]

commit ad8769aca03fbf80800bd7216ebf8e009f0ba33b
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Jun 3 15:35:21 2009 +0200

    Add mechanisms to TrackerDBInterface/TrackerDBManager to invalidate interfaces.
    
    On shutdown, all interfaces created through the DB manager will emit a
    "invalidated" signal, so callers have to do pending cleanups if necessary.
---
 src/libtracker-db/tracker-db-interface.c |    9 ++++++
 src/libtracker-db/tracker-db-manager.c   |   40 ++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+), 0 deletions(-)

diff --git a/src/libtracker-db/tracker-db-interface.c b/src/libtracker-db/tracker-db-interface.c
index 7cbfbc6..8ab7283 100644
--- a/src/libtracker-db/tracker-db-interface.c
+++ b/src/libtracker-db/tracker-db-interface.c
@@ -63,6 +63,15 @@ tracker_db_interface_error_quark (void)
 static void
 tracker_db_interface_class_init (gpointer iface)
 {
+	GType iface_type = G_TYPE_FROM_INTERFACE (iface);
+
+	g_signal_new ("invalidated",
+		      iface_type,
+		      G_SIGNAL_RUN_LAST,
+		      0, NULL, NULL,
+		      g_cclosure_marshal_VOID__VOID,
+		      G_TYPE_NONE, 0);
+
 	g_object_interface_install_property (iface,
 					     g_param_spec_boolean ("in-transaction",
 								   "In transaction",
diff --git a/src/libtracker-db/tracker-db-manager.c b/src/libtracker-db/tracker-db-manager.c
index 1fe426c..d13d9f9 100644
--- a/src/libtracker-db/tracker-db-manager.c
+++ b/src/libtracker-db/tracker-db-manager.c
@@ -220,6 +220,7 @@ static gchar		  *sys_tmp_dir;
 static gpointer		   db_type_enum_class_pointer;
 static TrackerDBInterface *file_iface;
 static TrackerDBInterface *email_iface;
+static GList              *not_owned_ifaces = NULL;
 
 static const gchar *
 location_to_directory (TrackerDBLocation location)
@@ -2364,6 +2365,23 @@ tracker_db_manager_init (TrackerDBManagerFlags	flags,
 	return TRUE;
 }
 
+static void
+invalidate_ifaces (void)
+{
+	GList *l;
+	gint i;
+
+	for (i = 1; i < G_N_ELEMENTS (dbs); i++) {
+		if (dbs[i].iface) {
+			g_signal_emit_by_name (dbs[i].iface, "invalidated");
+		}
+	}
+
+	for (l = not_owned_ifaces; l; l = l->next) {
+		g_signal_emit_by_name (l->data, "invalidated");
+	}
+}
+
 void
 tracker_db_manager_shutdown (void)
 {
@@ -2373,6 +2391,8 @@ tracker_db_manager_shutdown (void)
 		return;
 	}
 
+	invalidate_ifaces ();
+
 	for (i = 1; i < G_N_ELEMENTS (dbs); i++) {
 		if (dbs[i].abs_filename) {
 			g_free (dbs[i].abs_filename);
@@ -2429,6 +2449,9 @@ tracker_db_manager_shutdown (void)
 	tracker_ontology_shutdown ();
 
 	initialized = FALSE;
+
+	g_list_free (not_owned_ifaces);
+	not_owned_ifaces = NULL;
 }
 
 void
@@ -2484,6 +2507,13 @@ tracker_db_manager_get_file (TrackerDB db)
 	return dbs[db].abs_filename;
 }
 
+static void
+remove_not_owned_iface (gpointer  user_data,
+			GObject  *iface)
+{
+	not_owned_ifaces = g_list_remove (not_owned_ifaces, iface);
+}
+
 /**
  * tracker_db_manager_get_db_interfaces:
  * @num: amount of TrackerDB files wanted
@@ -2529,6 +2559,11 @@ tracker_db_manager_get_db_interfaces (gint num, ...)
 	}
 	va_end (args);
 
+	if (connection) {
+		not_owned_ifaces = g_list_prepend (not_owned_ifaces, connection);
+		g_object_weak_ref (G_OBJECT (connection), remove_not_owned_iface, NULL);
+	}
+
 	return connection;
 }
 
@@ -2563,6 +2598,11 @@ tracker_db_manager_get_db_interfaces_ro (gint num, ...)
 	}
 	va_end (args);
 
+	if (connection) {
+		not_owned_ifaces = g_list_prepend (not_owned_ifaces, connection);
+		g_object_weak_ref (G_OBJECT (connection), remove_not_owned_iface, NULL);
+	}
+
 	return connection;
 }