libtracker-sparql: Add private call to get remote DBus service details

When subscribing a TrackerNotifier to notifications from a remote DBus
service, we may need to perform translation of dbus names and object
paths, as this connection may be sandboxed.

Implement this plumbing so we may ask the TrackerSparqlConnection
about the real DBus details behind a SPARQL DBus endpoint.

Fixes: https://gitlab.gnome.org/GNOME/tracker/-/issues/287

3 files changed, 48 insertions, 2 deletions

diff --git a/src/libtracker-sparql/tracker-connection.c b/src/libtracker-sparql/tracker-connection.c
index 5dcc3d226..c6284d46e 100644
--- a/src/libtracker-sparql/tracker-connection.c
+++ b/src/libtracker-sparql/tracker-connection.c
@@ -93,6 +93,29 @@ tracker_sparql_connection_class_init (TrackerSparqlConnectionClass *klass)
 	object_class->dispose = tracker_sparql_connection_dispose;
 }
 
+gboolean
+tracker_sparql_connection_lookup_dbus_service (TrackerSparqlConnection  *connection,
+                                               const gchar              *dbus_name,
+                                               const gchar              *dbus_path,
+                                               gchar                   **name,
+                                               gchar                   **path)
+{
+	TrackerSparqlConnectionClass *connection_class;
+
+	g_return_val_if_fail (TRACKER_IS_SPARQL_CONNECTION (connection), FALSE);
+	g_return_val_if_fail (dbus_name != NULL, FALSE);
+
+	connection_class = TRACKER_SPARQL_CONNECTION_GET_CLASS (connection);
+	if (!connection_class->lookup_dbus_service)
+		return FALSE;
+
+	return TRACKER_SPARQL_CONNECTION_GET_CLASS (connection)->lookup_dbus_service (connection,
+	                                                                              dbus_name,
+	                                                                              dbus_path,
+	                                                                              name,
+	                                                                              path);
+}
+
 /* The constructor functions are defined in the libtracker-sparql-backend, but
  * documented here. */
 
diff --git a/src/libtracker-sparql/tracker-notifier.c b/src/libtracker-sparql/tracker-notifier.c
index cf1c9a9dd..fce0cbde5 100644
--- a/src/libtracker-sparql/tracker-notifier.c
+++ b/src/libtracker-sparql/tracker-notifier.c
@@ -50,6 +50,7 @@
 #include "tracker-private.h"
 #include "tracker-sparql-enum-types.h"
 #include <libtracker-common/tracker-common.h>
+#include <direct/tracker-direct.h>
 
 typedef struct _TrackerNotifierPrivate TrackerNotifierPrivate;
 typedef struct _TrackerNotifierSubscription TrackerNotifierSubscription;
@@ -811,6 +812,7 @@ tracker_notifier_signal_subscribe (TrackerNotifier *notifier,
 {
 	TrackerNotifierSubscription *subscription;
 	TrackerNotifierPrivate *priv;
+	gchar *dbus_name = NULL, *dbus_path = NULL;
 
 	g_return_val_if_fail (TRACKER_IS_NOTIFIER (notifier), 0);
 	g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
@@ -821,15 +823,21 @@ tracker_notifier_signal_subscribe (TrackerNotifier *notifier,
 	if (!object_path)
 		object_path = DEFAULT_OBJECT_PATH;
 
+	tracker_sparql_connection_lookup_dbus_service (priv->connection,
+	                                               service,
+	                                               object_path,
+	                                               &dbus_name,
+	                                               &dbus_path);
+
 	subscription = tracker_notifier_subscription_new (notifier, connection,
 	                                                  service, object_path);
 
 	subscription->handler_id =
 		g_dbus_connection_signal_subscribe (connection,
-		                                    service,
+		                                    dbus_name ? dbus_name : service,
 		                                    "org.freedesktop.Tracker3.Endpoint",
 		                                    "GraphUpdated",
-		                                    object_path,
+		                                    dbus_path ? dbus_path : object_path,
 		                                    graph,
 		                                    G_DBUS_SIGNAL_FLAGS_NONE,
 		                                    graph_updated_cb,
@@ -839,6 +847,9 @@ tracker_notifier_signal_subscribe (TrackerNotifier *notifier,
 	                     GUINT_TO_POINTER (subscription->handler_id),
 	                     subscription);
 
+	g_free (dbus_name);
+	g_free (dbus_path);
+
 	return subscription->handler_id;
 }
 
diff --git a/src/libtracker-sparql/tracker-private.h b/src/libtracker-sparql/tracker-private.h
index da93ac862..b8c6381ec 100644
--- a/src/libtracker-sparql/tracker-private.h
+++ b/src/libtracker-sparql/tracker-private.h
@@ -106,6 +106,12 @@ struct _TrackerSparqlConnectionClass
 					     GAsyncResult             *res,
 					     GError                  **error);
 	TrackerBatch * (* create_batch) (TrackerSparqlConnection *connection);
+
+	gboolean (* lookup_dbus_service) (TrackerSparqlConnection  *connection,
+	                                  const gchar              *dbus_name,
+	                                  const gchar              *dbus_path,
+	                                  gchar                   **name,
+	                                  gchar                   **path);
 };
 
 typedef struct _TrackerSparqlCursorClass TrackerSparqlCursorClass;
@@ -262,6 +268,12 @@ struct _TrackerSerializerClass {
 	GInputStreamClass parent_class;
 };
 
+gboolean
+tracker_sparql_connection_lookup_dbus_service (TrackerSparqlConnection  *connection,
+                                               const gchar              *dbus_name,
+                                               const gchar              *dbus_path,
+                                               gchar                   **name,
+                                               gchar                   **path);
 void tracker_sparql_cursor_set_connection (TrackerSparqlCursor     *cursor,
                                            TrackerSparqlConnection *connection);
 GError * _translate_internal_error (GError *error);