[tracker/wip/carlosg/tracker-3.0-api-breaks: 70/79] libtracker-sparql: Prepare for doing asynchronous queries

[Carlos Garnacho <carlosg src gnome org>]

commit 7837381b8b87a5a43a55f4c16471003bd25607a5
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Jan 26 23:37:00 2020 +0100

    libtracker-sparql: Prepare for doing asynchronous queries
    
    Operate on the cached elements as they are stored in the sequence
    and the cache struct, we will see it being passed along asynchronous
    queries soon.

 src/libtracker-sparql/tracker-notifier.c | 63 ++++++++++++++++----------------
 1 file changed, 31 insertions(+), 32 deletions(-)
---
diff --git a/src/libtracker-sparql/tracker-notifier.c b/src/libtracker-sparql/tracker-notifier.c
index 6ee186109..a1381a817 100644
--- a/src/libtracker-sparql/tracker-notifier.c
+++ b/src/libtracker-sparql/tracker-notifier.c
@@ -284,39 +284,37 @@ tracker_notifier_event_cache_take_events (TrackerNotifierEventCache *cache)
        return events;
 }
 
-static TrackerNotifierEvent *
-find_event_in_array (GPtrArray *events,
-                     gint64     id,
-                     gint      *idx)
+static void
+tracker_notifier_emit_events (TrackerNotifierEventCache *cache)
 {
-       TrackerNotifierEvent *event;
+       GPtrArray *events;
 
-       while (*idx < events->len) {
-               event = g_ptr_array_index (events, *idx);
-               (*idx)++;
-               if (event->id == id)
-                       return event;
-       }
+       events = tracker_notifier_event_cache_take_events (cache);
 
-       return NULL;
+       if (events) {
+               g_signal_emit (cache->notifier, signals[EVENTS], 0, cache->service, cache->graph, events);
+               g_ptr_array_unref (events);
+       }
 }
 
 static gchar *
-create_extra_info_query (TrackerNotifier *notifier,
-                         GPtrArray       *events)
+create_extra_info_query (TrackerNotifier           *notifier,
+                         TrackerNotifierEventCache *cache)
 {
        TrackerNotifierPrivate *priv;
        GString *sparql, *filter;
        gboolean has_elements = FALSE;
-       gint idx;
+       GSequenceIter *iter;
 
        priv = tracker_notifier_get_instance_private (notifier);
        filter = g_string_new (NULL);
 
-       for (idx = 0; idx < events->len; idx++) {
+       for (iter = g_sequence_get_begin_iter (cache->sequence);
+            !g_sequence_iter_is_end (iter);
+            iter = g_sequence_iter_next (iter)) {
                TrackerNotifierEvent *event;
 
-               event = g_ptr_array_index (events, idx);
+               event = g_sequence_get (iter);
 
                if (has_elements)
                        g_string_append_c (filter, ' ');
@@ -344,17 +342,18 @@ create_extra_info_query (TrackerNotifier *notifier,
 }
 
 static void
-tracker_notifier_query_extra_info (TrackerNotifier *notifier,
-                                   GPtrArray       *events)
+tracker_notifier_query_extra_info (TrackerNotifier           *notifier,
+                                   TrackerNotifierEventCache *cache)
 {
        TrackerNotifierPrivate *priv;
        TrackerSparqlCursor *cursor;
        TrackerNotifierEvent *event;
+       GSequenceIter *iter;
        gchar *sparql;
-       gint idx = 0, col;
+       gint col;
        gint64 id;
 
-       sparql = create_extra_info_query (notifier, events);
+       sparql = create_extra_info_query (notifier, cache);
        if (!sparql)
                return;
 
@@ -363,6 +362,8 @@ tracker_notifier_query_extra_info (TrackerNotifier *notifier,
                                                  NULL, NULL);
        g_free (sparql);
 
+       iter = g_sequence_get_begin_iter (cache->sequence);
+
        /* We rely here in both the GPtrArray and the query items being
         * sorted by tracker:id, the former will be so because the way it's
         * extracted from the GSequence, the latter because of the ORDER BY
@@ -371,9 +372,10 @@ tracker_notifier_query_extra_info (TrackerNotifier *notifier,
        while (tracker_sparql_cursor_next (cursor, NULL, NULL)) {
                col = 0;
                id = tracker_sparql_cursor_get_integer (cursor, col++);
-               event = find_event_in_array (events, id, &idx);
+               event = g_sequence_get (iter);
+               iter = g_sequence_iter_next (iter);
 
-               if (!event) {
+               if (!event || event->id != id) {
                        g_critical ("Queried for id %" G_GINT64_FORMAT " but it is not "
                                    "found, bailing out", id);
                        break;
@@ -391,17 +393,15 @@ _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 (g_sequence_is_empty (cache->sequence))
+               _tracker_notifier_event_cache_free (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_info (notifier, cache);
 
-               g_signal_emit (notifier, signals[EVENTS], 0, cache->service, cache->graph, events);
-               g_ptr_array_unref (events);
-       }
+       tracker_notifier_emit_events (cache);
+       _tracker_notifier_event_cache_free (cache);
 }
 
 static void
@@ -429,7 +429,6 @@ graph_updated_cb (GDBusConnection *connection,
        g_variant_iter_free (events);
 
        _tracker_notifier_event_cache_flush_events (cache);
-       _tracker_notifier_event_cache_free (cache);
 }
 
 static void