A more efficient strategy for introspection XML generation (only when it is requested and the object information has changed since the last generation)

1 files changed, 97 insertions, 91 deletions

diff --git a/common/dbus-helper.c b/common/dbus-helper.c
index 639b6d3f..40cd3eac 100644
--- a/common/dbus-helper.c
+++ b/common/dbus-helper.c
@@ -61,93 +61,6 @@ DBusHandlerResult dbus_connection_send_and_unref(DBusConnection *connection,
 	return DBUS_HANDLER_RESULT_HANDLED;
 }
 
-static DBusHandlerResult introspect(DBusConnection *connection,
-				DBusMessage *message, struct generic_data *data)
-{
-	DBusMessage *reply;
-
-	if (dbus_message_has_signature(message,
-				DBUS_TYPE_INVALID_AS_STRING) == FALSE) {
-		error("Unexpected signature to introspect call");
-		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
-	}
-
-	if (!data->introspect)
-		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
-
-	reply = dbus_message_new_method_return(message);
-	if (!reply)
-		return DBUS_HANDLER_RESULT_NEED_MEMORY;
-
-	dbus_message_append_args(reply, DBUS_TYPE_STRING, &data->introspect,
-					DBUS_TYPE_INVALID);
-
-	return dbus_connection_send_and_unref(connection, reply);
-}
-
-static void generic_unregister(DBusConnection *connection, void *user_data)
-{
-	struct generic_data *data = user_data;
-
-	if (data->unregister_function)
-		data->unregister_function(connection, data->user_data);
-
-	g_free(data->introspect);
-	g_free(data);
-}
-
-static struct interface_data *find_interface(GSList *interfaces,
-						const char *name)
-{
-	GSList *list;
-
-	for (list = interfaces; list; list = list->next) {
-		struct interface_data *iface = list->data;
-		if (!strcmp(name, iface->name))
-			return iface;
-	}
-
-	return NULL;
-}
-
-static DBusHandlerResult generic_message(DBusConnection *connection,
-					DBusMessage *message, void *user_data)
-{
-	struct generic_data *data = user_data;
-	struct interface_data *iface;
-	DBusMethodVTable *current;
-	const char *interface;
-
-	if (dbus_message_is_method_call(message, DBUS_INTERFACE_INTROSPECTABLE,
-							"Introspect") == TRUE)
-		return introspect(connection, message, data);
-
-	interface = dbus_message_get_interface(message);
-
-	iface = find_interface(data->interfaces, interface);
-	if (!iface)
-		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
-
-	for (current = iface->methods;
-			current->name && current->message_function; current++) {
-		if (dbus_message_is_method_call(message,
-				iface->name, current->name) == FALSE)
-			continue;
-
-		if (dbus_message_has_signature(message,
-				current->signature) == TRUE)
-			return current->message_function(connection,
-						message, data->user_data);
-	}
-
-	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
-}
-
-static DBusObjectPathVTable generic_table = {
-	.unregister_function	= generic_unregister,
-	.message_function	= generic_message,
-};
-
 static void print_arguments(GString *gstr, const char *sig, const char *direction)
 {
 	int i;
@@ -206,7 +119,9 @@ static void print_arguments(GString *gstr, const char *sig, const char *directio
 	}
 }
 
-static void update_introspection_data(DBusConnection *conn, struct generic_data *data, const char *path)
+static void generate_introspection_xml(DBusConnection *conn,
+					struct generic_data *data,
+					const char *path)
 {
 	GSList *list;
 	GString *gstr;
@@ -278,6 +193,94 @@ done:
 	data->introspect = g_string_free(gstr, FALSE);
 }
 
+static DBusHandlerResult introspect(DBusConnection *connection,
+				DBusMessage *message, struct generic_data *data)
+{
+	DBusMessage *reply;
+
+	if (dbus_message_has_signature(message,
+				DBUS_TYPE_INVALID_AS_STRING) == FALSE) {
+		error("Unexpected signature to introspect call");
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+	}
+
+	if (!data->introspect)
+		generate_introspection_xml(connection, data,
+						dbus_message_get_path(message));
+
+	reply = dbus_message_new_method_return(message);
+	if (!reply)
+		return DBUS_HANDLER_RESULT_NEED_MEMORY;
+
+	dbus_message_append_args(reply, DBUS_TYPE_STRING, &data->introspect,
+					DBUS_TYPE_INVALID);
+
+	return dbus_connection_send_and_unref(connection, reply);
+}
+
+static void generic_unregister(DBusConnection *connection, void *user_data)
+{
+	struct generic_data *data = user_data;
+
+	if (data->unregister_function)
+		data->unregister_function(connection, data->user_data);
+
+	g_free(data->introspect);
+	g_free(data);
+}
+
+static struct interface_data *find_interface(GSList *interfaces,
+						const char *name)
+{
+	GSList *list;
+
+	for (list = interfaces; list; list = list->next) {
+		struct interface_data *iface = list->data;
+		if (!strcmp(name, iface->name))
+			return iface;
+	}
+
+	return NULL;
+}
+
+static DBusHandlerResult generic_message(DBusConnection *connection,
+					DBusMessage *message, void *user_data)
+{
+	struct generic_data *data = user_data;
+	struct interface_data *iface;
+	DBusMethodVTable *current;
+	const char *interface;
+
+	if (dbus_message_is_method_call(message, DBUS_INTERFACE_INTROSPECTABLE,
+							"Introspect") == TRUE)
+		return introspect(connection, message, data);
+
+	interface = dbus_message_get_interface(message);
+
+	iface = find_interface(data->interfaces, interface);
+	if (!iface)
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+
+	for (current = iface->methods;
+			current->name && current->message_function; current++) {
+		if (dbus_message_is_method_call(message,
+				iface->name, current->name) == FALSE)
+			continue;
+
+		if (dbus_message_has_signature(message,
+				current->signature) == TRUE)
+			return current->message_function(connection,
+						message, data->user_data);
+	}
+
+	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static DBusObjectPathVTable generic_table = {
+	.unregister_function	= generic_unregister,
+	.message_function	= generic_message,
+};
+
 static void update_parent_data(DBusConnection *conn, const char *child_path)
 {
 	struct generic_data *data;
@@ -299,7 +302,8 @@ static void update_parent_data(DBusConnection *conn, const char *child_path)
 	if (!data)
 		goto done;
 
-	update_introspection_data(conn, data, parent_path);
+	g_free(data->introspect);
+	data->introspect = NULL;
 
 done:
 	g_free(parent_path);
@@ -380,7 +384,8 @@ dbus_bool_t dbus_connection_register_interface(DBusConnection *connection,
 
 	data->interfaces = g_slist_append(data->interfaces, iface);
 
-	update_introspection_data(connection, data, path);
+	g_free(data->introspect);
+	data->introspect = NULL;
 
 	return TRUE;
 }
@@ -404,7 +409,8 @@ dbus_bool_t dbus_connection_unregister_interface(DBusConnection *connection,
 	g_free(iface->name);
 	g_free(iface);
 
-	update_introspection_data(connection, data, path);
+	g_free(data->introspect);
+	data->introspect = NULL;
 
 	return TRUE;
 }