[tracker] TrackerDecorator: Fix infinite loop

[Xavier Claessens <xclaesse src gnome org>]

commit 476eb8c5257b195d133f817c4d020bfaaa1120e5
Author: Xavier Claessens <xavier claessens collabora co uk>
Date:   Fri Feb 7 14:12:56 2014 -0500

    TrackerDecorator: Fix infinite loop
    
    If some ids already have a nie:dataSource, they will never be removed
    from our queue. This is a regression introduced by commit 94d4a85.

 src/libtracker-miner/tracker-decorator.c |   55 +++++++++++++++++++++++-------
 1 files changed, 42 insertions(+), 13 deletions(-)
---
diff --git a/src/libtracker-miner/tracker-decorator.c b/src/libtracker-miner/tracker-decorator.c
index 6b1c113..2b907bf 100644
--- a/src/libtracker-miner/tracker-decorator.c
+++ b/src/libtracker-miner/tracker-decorator.c
@@ -1008,15 +1008,25 @@ tracker_decorator_delete_id (TrackerDecorator *decorator,
 
 static void complete_tasks_or_query (TrackerDecorator *decorator);
 
+typedef struct {
+       TrackerDecorator *decorator;
+       GArray *ids;
+} QueryNextItemsData;
+
 static void
 query_next_items_cb (GObject      *object,
                      GAsyncResult *result,
                      gpointer      user_data)
 {
-       TrackerDecorator *decorator = user_data;
+       QueryNextItemsData *data = user_data;
+       TrackerDecorator *decorator = data->decorator;
        TrackerDecoratorPrivate *priv;
        TrackerSparqlConnection *conn;
        TrackerSparqlCursor *cursor;
+       GList *elem;
+       ElemNode *node;
+       gint id;
+       guint i;
        GError *error = NULL;
 
        conn = TRACKER_SPARQL_CONNECTION (object);
@@ -1032,23 +1042,37 @@ query_next_items_cb (GObject      *object,
                }
 
                g_clear_error (&error);
-               return;
+               goto out;
        }
 
        while (tracker_sparql_cursor_next (cursor, NULL, NULL)) {
-               GList *elem;
-               ElemNode *node;
-               gint id;
-
                id = tracker_sparql_cursor_get_integer (cursor, 1);
                elem = g_hash_table_lookup (priv->elems, GINT_TO_POINTER (id));
+               if (!elem)
+                       continue;
+
                node = elem->data;
                node->info = tracker_decorator_info_new (cursor);
        }
 
-       g_object_unref (cursor);
+       /* Remove elements that we queried but we didn't get info */
+       for (i = 0; i < data->ids->len; i++) {
+               id = g_array_index (data->ids, gint, i);
+               elem = g_hash_table_lookup (priv->elems, GINT_TO_POINTER (id));
+               if (!elem)
+                       continue;
+
+               node = elem->data;
+               if (!node->info)
+                       element_remove_link (decorator, elem);
+       }
 
        complete_tasks_or_query (decorator);
+
+out:
+       g_clear_object (&cursor);
+       g_array_unref (data->ids);
+       g_slice_free (QueryNextItemsData, data);
 }
 
 static void
@@ -1059,12 +1083,18 @@ query_next_items (TrackerDecorator *decorator,
        TrackerDecoratorPrivate *priv;
        GString *id_string;
        gchar *query;
-       guint count = 0;
+       QueryNextItemsData *data;
 
        priv = decorator->priv;
 
+       data = g_slice_new0 (QueryNextItemsData);
+       data->decorator = decorator;
+       data->ids = g_array_sized_new (FALSE, FALSE,
+                                      sizeof (gint),
+                                      QUERY_BATCH_SIZE);
+
        id_string = g_string_new (NULL);
-       for (; l != NULL && count < QUERY_BATCH_SIZE; l = l->next) {
+       for (; l != NULL && data->ids->len < QUERY_BATCH_SIZE; l = l->next) {
                ElemNode *node = l->data;
 
                if (node->info)
@@ -1072,12 +1102,11 @@ query_next_items (TrackerDecorator *decorator,
 
                if (id_string->len > 0)
                        g_string_append_c (id_string, ',');
-
                g_string_append_printf (id_string, "%d", node->id);
-               count++;
+               g_array_append_val (data->ids, node->id);
        }
 
-       g_assert (count > 0);
+       g_assert (data->ids->len > 0);
 
        query = g_strdup_printf ("SELECT ?urn"
                                 "       tracker:id(?urn) "
@@ -1091,7 +1120,7 @@ query_next_items (TrackerDecorator *decorator,
        sparql_conn = tracker_miner_get_connection (TRACKER_MINER (decorator));
        tracker_sparql_connection_query_async (sparql_conn, query,
                                               NULL,
-                                              query_next_items_cb, decorator);
+                                              query_next_items_cb, data);
        g_string_free (id_string, TRUE);
        g_free (query);
 }