[tracker/wip/carlosg/tracker-3.0-api-breaks: 20/100] libtracker-sparql: Make TrackerNotifierEventCache more standalone

[Carlos Garnacho <carlosg src gnome org>]

commit e64fad67e421cf9a21cd4695a4879f883dd7cf1b
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Dec 20 13:48:11 2019 +0100

    libtracker-sparql: Make TrackerNotifierEventCache more standalone
    
    Instead of just caching the events, it can now also flush them. This
    will make the object useful to be exported, and hooked through
    different ways internally. In future commits though.

 src/libtracker-sparql/tracker-notifier.c | 106 ++++++++++++++++---------------
 1 file changed, 54 insertions(+), 52 deletions(-)
---
diff --git a/src/libtracker-sparql/tracker-notifier.c b/src/libtracker-sparql/tracker-notifier.c
index 671f7eaaa..21fadc100 100644
--- a/src/libtracker-sparql/tracker-notifier.c
+++ b/src/libtracker-sparql/tracker-notifier.c
@@ -80,7 +80,6 @@ struct _TrackerNotifierPrivate {
        GDBusConnection *dbus_connection;
        TrackerNotifierFlags flags;
        GHashTable *cached_ids; /* gchar -> gint64* */
-       GHashTable *cached_events; /* gchar -> GSequence */
        gchar **expanded_classes;
        gchar **classes;
        guint graph_updated_signal_id;
@@ -89,6 +88,7 @@ struct _TrackerNotifierPrivate {
 
 struct _TrackerNotifierEventCache {
        gchar *class;
+       TrackerNotifier *notifier;
        GSequence *sequence;
 };
 
@@ -203,11 +203,13 @@ compare_event_cb (gconstpointer a,
 }
 
 static TrackerNotifierEventCache *
-tracker_notifier_event_cache_new (const gchar *rdf_class)
+tracker_notifier_event_cache_new (TrackerNotifier *notifier,
+                                  const gchar     *rdf_class)
 {
        TrackerNotifierEventCache *event_cache;
 
        event_cache = g_new0 (TrackerNotifierEventCache, 1);
+       event_cache->notifier = g_object_ref (notifier);
        event_cache->class = g_strdup (rdf_class);
        event_cache->sequence = g_sequence_new ((GDestroyNotify) tracker_notifier_event_unref);
 
@@ -218,29 +220,11 @@ static void
 tracker_notifier_event_cache_free (TrackerNotifierEventCache *event_cache)
 {
        g_sequence_free (event_cache->sequence);
+       g_object_unref (event_cache->notifier);
        g_free (event_cache->class);
        g_free (event_cache);
 }
 
-static TrackerNotifierEventCache *
-tracker_notifier_get_event_cache (TrackerNotifier *notifier,
-                                  const gchar     *rdf_class)
-{
-       TrackerNotifierPrivate *priv;
-       TrackerNotifierEventCache *event_cache;
-
-       priv = tracker_notifier_get_instance_private (notifier);
-       event_cache = g_hash_table_lookup (priv->cached_events, rdf_class);
-
-       if (!event_cache) {
-               event_cache = tracker_notifier_event_cache_new (rdf_class);
-               g_hash_table_insert (priv->cached_events,
-                                    event_cache->class, event_cache);
-       }
-
-       return event_cache;
-}
-
 /* This is always meant to return a pointer */
 static TrackerNotifierEvent *
 tracker_notifier_event_cache_get_event (TrackerNotifierEventCache *cache,
@@ -270,6 +254,19 @@ tracker_notifier_event_cache_get_event (TrackerNotifierEventCache *cache,
        return event;
 }
 
+static void
+tracker_notifier_event_cache_push_event (TrackerNotifierEventCache *cache,
+                                         gint64                     id,
+                                         TrackerNotifierEventType   event_type)
+{
+       TrackerNotifierEvent *event;
+
+       event = tracker_notifier_event_cache_get_event (cache, id);
+
+       if (event->type < 0 || event_type != TRACKER_NOTIFIER_EVENT_UPDATE)
+               event->type = event_type;
+}
+
 static void
 handle_deletes (TrackerNotifier           *notifier,
                 TrackerNotifierEventCache *cache,
@@ -279,15 +276,15 @@ handle_deletes (TrackerNotifier           *notifier,
 
        while (g_variant_iter_loop (iter, "(iiii)",
                                    &graph, &subject, &predicate, &object)) {
-               TrackerNotifierEvent *event;
-
-               event = tracker_notifier_event_cache_get_event (cache, subject);
+               TrackerNotifierEventType type;
 
                if (tracker_notifier_id_matches (notifier, predicate, "rdf:type")) {
-                       event->type = TRACKER_NOTIFIER_EVENT_DELETE;
-               } else if (event->type < 0) {
-                       event->type = TRACKER_NOTIFIER_EVENT_UPDATE;
+                       type = TRACKER_NOTIFIER_EVENT_DELETE;
+               } else {
+                       type = TRACKER_NOTIFIER_EVENT_UPDATE;
                }
+
+               tracker_notifier_event_cache_push_event (cache, subject, type);
        }
 }
 
@@ -300,20 +297,20 @@ handle_updates (TrackerNotifier           *notifier,
 
        while (g_variant_iter_loop (iter, "(iiii)",
                                    &graph, &subject, &predicate, &object)) {
-               TrackerNotifierEvent *event;
-
-               event = tracker_notifier_event_cache_get_event (cache, subject);
+               TrackerNotifierEventType type;
 
                if (tracker_notifier_id_matches (notifier, predicate, "rdf:type")) {
-                       event->type = TRACKER_NOTIFIER_EVENT_CREATE;
-               } else if (event->type < 0) {
-                       event->type = TRACKER_NOTIFIER_EVENT_UPDATE;
+                       type = TRACKER_NOTIFIER_EVENT_CREATE;
+               } else {
+                       type = TRACKER_NOTIFIER_EVENT_UPDATE;
                }
+
+               tracker_notifier_event_cache_push_event (cache, subject, type);
        }
 }
 
 static GPtrArray *
-tracker_notifier_event_cache_flush_events (TrackerNotifierEventCache *cache)
+tracker_notifier_event_cache_take_events (TrackerNotifierEventCache *cache)
 {
        TrackerNotifierEvent *event;
        GSequenceIter *iter, *next;
@@ -534,6 +531,26 @@ tracker_notifier_query_extra_deleted_info (TrackerNotifier *notifier,
        g_object_unref (cursor);
 }
 
+static void
+tracker_notifier_event_cache_flush_events (TrackerNotifierEventCache *cache)
+{
+       TrackerNotifier *notifier = cache->notifier;
+       TrackerNotifierPrivate *priv = tracker_notifier_get_instance_private (notifier);
+       GPtrArray *events;
+
+       events = tracker_notifier_event_cache_take_events (cache);
+
+       if (events) {
+               if (priv->flags & TRACKER_NOTIFIER_FLAG_QUERY_URN) {
+                       tracker_notifier_query_extra_info (notifier, events);
+                       tracker_notifier_query_extra_deleted_info (notifier, events);
+               }
+
+               g_signal_emit (notifier, signals[EVENTS], 0, events);
+               g_ptr_array_unref (events);
+       }
+}
+
 static void
 graph_updated_cb (GDBusConnection *connection,
                   const gchar     *sender_name,
@@ -547,7 +564,6 @@ graph_updated_cb (GDBusConnection *connection,
        TrackerNotifierPrivate *priv;
        TrackerNotifierEventCache *cache;
        GVariantIter *deletes, *updates;
-       GPtrArray *events;
        const gchar *class;
 
        priv = tracker_notifier_get_instance_private (notifier);
@@ -561,24 +577,15 @@ graph_updated_cb (GDBusConnection *connection,
                return;
        }
 
-       cache = tracker_notifier_get_event_cache (notifier, class);
+       cache = tracker_notifier_event_cache_new (notifier, class);
        handle_deletes (notifier, cache, deletes);
        handle_updates (notifier, cache, updates);
 
        g_variant_iter_free (deletes);
        g_variant_iter_free (updates);
 
-       events = tracker_notifier_event_cache_flush_events (cache);
-       if (events) {
-               if (priv->flags & TRACKER_NOTIFIER_FLAG_QUERY_URN)
-                       tracker_notifier_query_extra_info (notifier, events);
-
-               if (priv->flags & TRACKER_NOTIFIER_FLAG_QUERY_URN)
-                       tracker_notifier_query_extra_deleted_info (notifier, events);
-
-               g_signal_emit (notifier, signals[EVENTS], 0, events);
-               g_ptr_array_unref (events);
-       }
+       tracker_notifier_event_cache_flush_events (cache);
+       tracker_notifier_event_cache_free (cache);
 }
 
 static gboolean
@@ -747,7 +754,6 @@ tracker_notifier_finalize (GObject *object)
                g_object_unref (priv->connection);
 
        g_hash_table_unref (priv->cached_ids);
-       g_hash_table_unref (priv->cached_events);
        g_strfreev (priv->expanded_classes);
        g_strfreev (priv->classes);
 
@@ -817,10 +823,6 @@ tracker_notifier_init (TrackerNotifier *notifier)
        TrackerNotifierPrivate *priv;
 
        priv = tracker_notifier_get_instance_private (notifier);
-       priv->cached_events = g_hash_table_new_full (g_str_hash,
-                                                    g_str_equal,
-                                                    NULL,
-                                                    (GDestroyNotify) tracker_notifier_event_cache_free);
        priv->cached_ids = g_hash_table_new_full (g_str_hash,
                                                  g_str_equal,
                                                  g_free, g_free);