[tracker/wip/carlosg/tracker-3.0-api-breaks: 82/95] libtracker-sparql: Always emit TrackerNotifier::events on an idle

[Carlos Garnacho <carlosg src gnome org>]

commit 6b590f6b3ced10a3c52f83eba9bf3b61759f8db8
Author: Carlos Garnacho <carlosg gnome org>
Date:   Mon Jan 27 13:51:05 2020 +0100

    libtracker-sparql: Always emit TrackerNotifier::events on an idle
    
    This ensures the callback will be dispatched outside of the updates
    thread, and presumably into the main application thread/main context.
    Also makes this function dependent on a main loop.

 src/libtracker-sparql/tracker-notifier.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)
---
diff --git a/src/libtracker-sparql/tracker-notifier.c b/src/libtracker-sparql/tracker-notifier.c
index c1fe97fdb..332483cd3 100644
--- a/src/libtracker-sparql/tracker-notifier.c
+++ b/src/libtracker-sparql/tracker-notifier.c
@@ -289,7 +289,7 @@ tracker_notifier_event_cache_take_events (TrackerNotifierEventCache *cache)
        return events;
 }
 
-static void
+static gboolean
 tracker_notifier_emit_events (TrackerNotifierEventCache *cache)
 {
        GPtrArray *events;
@@ -300,6 +300,17 @@ tracker_notifier_emit_events (TrackerNotifierEventCache *cache)
                g_signal_emit (cache->notifier, signals[EVENTS], 0, cache->service, cache->graph, events);
                g_ptr_array_unref (events);
        }
+
+       return G_SOURCE_REMOVE;
+}
+
+static void
+tracker_notifier_emit_events_in_idle (TrackerNotifierEventCache *cache)
+{
+       g_idle_add_full (G_PRIORITY_DEFAULT,
+                        (GSourceFunc) tracker_notifier_emit_events,
+                        cache,
+                        (GDestroyNotify) _tracker_notifier_event_cache_free);
 }
 
 static gchar *
@@ -389,8 +400,7 @@ query_extra_info_cb (GObject      *object,
 
        g_object_unref (cursor);
 
-       tracker_notifier_emit_events (cache);
-       _tracker_notifier_event_cache_free (cache);
+       tracker_notifier_emit_events_in_idle (cache);
 }
 
 static void
@@ -418,14 +428,15 @@ _tracker_notifier_event_cache_flush_events (TrackerNotifierEventCache *cache)
        TrackerNotifier *notifier = cache->notifier;
        TrackerNotifierPrivate *priv = tracker_notifier_get_instance_private (notifier);
 
-       if (g_sequence_is_empty (cache->sequence))
+       if (g_sequence_is_empty (cache->sequence)) {
                _tracker_notifier_event_cache_free (cache);
+               return;
+       }
 
        if (priv->flags & TRACKER_NOTIFIER_FLAG_QUERY_URN) {
                tracker_notifier_query_extra_info (notifier, cache);
        } else {
-               tracker_notifier_emit_events (cache);
-               _tracker_notifier_event_cache_free (cache);
+               tracker_notifier_emit_events_in_idle (cache);
        }
 }