[tracker-miners/wip/carlosg/writeback-refactor: 6/13] tracker-writeback: Drop implicit/explicit task cancellation

[Carlos Garnacho <carlosg src gnome org>]

commit be476c7bf5c3415d4e1fadcaa44454f7e837f74d
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed May 20 13:35:06 2020 +0200

    tracker-writeback: Drop implicit/explicit task cancellation
    
    Writeback is an operation important enough that we don't want
    to leave it at an arbitrary (even though atomic) state. Drop
    the explicit DBus method call to cancel tasks, and the implicit
    volume unmount handling (which was otoh way way too late, we
    wanted pre-unmount there).

 src/tracker-writeback/tracker-writeback.c | 122 +-----------------------------
 1 file changed, 1 insertion(+), 121 deletions(-)
---
diff --git a/src/tracker-writeback/tracker-writeback.c b/src/tracker-writeback/tracker-writeback.c
index 1a48bfd87..8be5a9040 100644
--- a/src/tracker-writeback/tracker-writeback.c
+++ b/src/tracker-writeback/tracker-writeback.c
@@ -45,7 +45,6 @@ typedef struct {
        GPtrArray *results;
        TrackerSparqlConnection *connection;
        GList *writeback_handlers;
-       guint cancel_id;
        GError *error;
 } WritebackData;
 
@@ -53,8 +52,6 @@ typedef struct {
        GMainContext *context;
        GMainLoop *main_loop;
 
-       GVolumeMonitor *volume_monitor;
-
        GDBusConnection *d_connection;
        GDBusNodeInfo *introspection_data;
        guint registration_id;
@@ -91,9 +88,6 @@ static const gchar *introspection_xml =
        "      <arg type='as' name='rdf_types' direction='in' />"
        "      <arg type='aas' name='results' direction='in' />"
        "    </method>"
-       "    <method name='CancelTasks'>"
-       "      <arg type='as' name='subjects' direction='in' />"
-       "    </method>"
        "  </interface>"
        "</node>";
 
@@ -144,7 +138,6 @@ tracker_controller_finalize (GObject *object)
 
        tracker_controller_dbus_stop (controller);
 
-       g_object_unref (priv->volume_monitor);
        g_hash_table_unref (priv->modules);
 
        g_main_loop_unref (priv->main_loop);
@@ -207,27 +200,6 @@ tracker_controller_class_init (TrackerControllerClass *klass)
                                                            G_PARAM_STATIC_STRINGS));
 }
 
-static void
-task_cancellable_cancelled_cb (GCancellable  *cancellable,
-                               WritebackData *data)
-{
-       TrackerControllerPrivate *priv;
-
-       priv = tracker_controller_get_instance_private (data->controller);
-
-       g_mutex_lock (&priv->mutex);
-
-       if (priv->current == data) {
-               g_message ("Cancelled writeback task for '%s' was currently being "
-                          "processed, _exit()ing immediately",
-                          data->subject);
-               _exit (0);
-       }
-
-       g_mutex_unlock (&priv->mutex);
-}
-
-
 static WritebackData *
 writeback_data_new (TrackerController       *controller,
                     GList                   *writeback_handlers,
@@ -250,10 +222,6 @@ writeback_data_new (TrackerController       *controller,
        data->request = request;
        data->error = NULL;
 
-       data->cancel_id = g_cancellable_connect (data->cancellable,
-                                                G_CALLBACK (task_cancellable_cancelled_cb),
-                                                data, NULL);
-
        return data;
 }
 
@@ -263,7 +231,6 @@ writeback_data_free (WritebackData *data)
        /* We rely on data->invocation being freed through
         * the g_dbus_method_invocation_return_* methods
         */
-       g_cancellable_disconnect (data->cancellable, data->cancel_id);
        g_free (data->subject);
        g_object_unref (data->connection);
        g_ptr_array_unref (data->results);
@@ -278,57 +245,6 @@ writeback_data_free (WritebackData *data)
        g_slice_free (WritebackData, data);
 }
 
-static void
-cancel_tasks (TrackerController *controller,
-              const gchar       *subject,
-              GFile             *file)
-{
-       TrackerControllerPrivate *priv;
-       GList *elem;
-
-       priv = tracker_controller_get_instance_private (controller);
-
-       for (elem = priv->ongoing_tasks; elem; elem = elem->next) {
-               WritebackData *data = elem->data;
-
-               if (g_strcmp0 (subject, data->subject) == 0) {
-                       g_message ("Cancelling not yet processed task ('%s')",
-                                  data->subject);
-                       g_cancellable_cancel (data->cancellable);
-               }
-
-               if (file) {
-                       guint i;
-                       for (i = 0; i < data->results->len; i++) {
-                               GStrv row = g_ptr_array_index (data->results, i);
-                               if (row[0] != NULL) {
-                                       GFile *task_file;
-                                       task_file = g_file_new_for_uri (row[0]);
-                                       if (g_file_equal (task_file, file) ||
-                                           g_file_has_prefix (task_file, file)) {
-                                               /* Mount path contains some file being processed */
-                                               g_message ("Cancelling task ('%s')", row[0]);
-                                               g_cancellable_cancel (data->cancellable);
-                                       }
-                                       g_object_unref (task_file);
-                               }
-                       }
-               }
-       }
-}
-
-static void
-mount_point_removed_cb (GVolumeMonitor *monitor,
-                        GMount         *mount,
-                        gpointer        user_data)
-{
-       GFile *mount_file;
-
-       mount_file = g_mount_get_root (mount);
-       cancel_tasks (TRACKER_CONTROLLER (user_data), NULL, mount_file);
-       g_object_unref (mount_file);
-}
-
 static gboolean
 reset_shutdown_timeout_cb (gpointer user_data)
 {
@@ -386,10 +302,6 @@ tracker_controller_init (TrackerController *controller)
        priv->context = g_main_context_new ();
        priv->main_loop = g_main_loop_new (priv->context, FALSE);
 
-       priv->volume_monitor = g_volume_monitor_get ();
-       g_signal_connect_object (priv->volume_monitor, "mount-removed",
-                                G_CALLBACK (mount_point_removed_cb), controller, 0);
-
        g_cond_init (&priv->initialization_cond);
        g_mutex_init (&priv->initialization_mutex);
        g_mutex_init (&priv->mutex);
@@ -611,34 +523,6 @@ handle_method_call_perform_writeback (TrackerController     *controller,
        g_free (rdf_types);
 }
 
-static void
-handle_method_call_cancel_tasks (TrackerController     *controller,
-                                 GDBusMethodInvocation *invocation,
-                                 GVariant              *parameters)
-{
-       TrackerDBusRequest *request;
-       gchar **subjects;
-       gint i;
-
-#ifdef THREAD_ENABLE_TRACE
-       g_debug ("Thread:%p (Controller) --> Got Tasks cancellation request",
-                g_thread_self ());
-#endif /* THREAD_ENABLE_TRACE */
-
-
-       g_variant_get (parameters, "(^as)", &subjects);
-
-       request = tracker_dbus_request_begin (NULL, "%s (%s, ...)", __FUNCTION__, subjects[0]);
-
-       for (i = 0; subjects[i] != NULL; i++) {
-               cancel_tasks (controller, subjects[i], NULL);
-       }
-
-       g_strfreev (subjects);
-       tracker_dbus_request_end (request, NULL);
-       g_dbus_method_invocation_return_value (invocation, NULL);
-}
-
 static void
 handle_method_call (GDBusConnection       *connection,
                     const gchar           *sender,
@@ -655,8 +539,6 @@ handle_method_call (GDBusConnection       *connection,
                handle_method_call_get_pid (controller, invocation, parameters);
        } else if (g_strcmp0 (method_name, "PerformWriteback") == 0) {
                handle_method_call_perform_writeback (controller, invocation, parameters);
-       } else if (g_strcmp0 (method_name, "CancelTasks") == 0) {
-               handle_method_call_cancel_tasks (controller, invocation, parameters);
        } else {
                g_warning ("Unknown method '%s' called", method_name);
        }
@@ -861,9 +743,7 @@ tracker_controller_thread_func (gpointer user_data)
 
        g_object_unref (controller);
 
-       /* This is where we exit, be it
-        * either through umount events on monitored
-        * files' volumes or the timeout being reached
+       /* This is where we exit through the timeout being reached
         */
        exit (0);
        return NULL;