[tracker/wip/carlosg/sparql1.1: 51/113] libtracker-data: Drop TrackerClass count parameter

[Carlos Garnacho <carlosg src gnome org>]

commit e9630df716eba857e2e110ad15337ac77eba796c
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Jun 16 21:29:51 2019 +0200

    libtracker-data: Drop TrackerClass count parameter
    
    It used to keep accounting of how many resources of the given TrackerClass
    there are, but it's largely unused. Funnily, the Statistics tracker-store
    interface only used tracker_class_set/get_count() as storage for its own
    accounting, so just make it have a hashtable.

 src/libtracker-data/libtracker-data.vapi  |  1 -
 src/libtracker-data/tracker-class.c       | 27 ---------------
 src/libtracker-data/tracker-class.h       |  3 --
 src/libtracker-data/tracker-data-update.c | 55 -------------------------------
 src/tracker-store/tracker-statistics.vala | 38 ++++++++++-----------
 5 files changed, 18 insertions(+), 106 deletions(-)
---
diff --git a/src/libtracker-data/libtracker-data.vapi b/src/libtracker-data/libtracker-data.vapi
index be1bcf118..4327be918 100644
--- a/src/libtracker-data/libtracker-data.vapi
+++ b/src/libtracker-data/libtracker-data.vapi
@@ -122,7 +122,6 @@ namespace Tracker {
        public class Class : GLib.Object {
                public string name { get; set; }
                public string uri { get; set; }
-               public int count { get; set; }
                [CCode (array_length = false, array_null_terminated = true)]
                public unowned Class[] get_super_classes ();
                public void transact_events ();
diff --git a/src/libtracker-data/tracker-class.c b/src/libtracker-data/tracker-class.c
index 76d5416c9..47bf8439f 100644
--- a/src/libtracker-data/tracker-class.c
+++ b/src/libtracker-data/tracker-class.c
@@ -34,7 +34,6 @@ typedef struct _TrackerClassPrivate TrackerClassPrivate;
 struct _TrackerClassPrivate {
        gchar *uri;
        gchar *name;
-       gint count;
        gint id;
        gboolean is_new;
        gboolean db_schema_changed;
@@ -140,18 +139,6 @@ tracker_class_get_name (TrackerClass *service)
        return priv->name;
 }
 
-gint
-tracker_class_get_count (TrackerClass *service)
-{
-       TrackerClassPrivate *priv;
-
-       g_return_val_if_fail (TRACKER_IS_CLASS (service), 0);
-
-       priv = tracker_class_get_instance_private (service);
-
-       return priv->count;
-}
-
 gint
 tracker_class_get_id (TrackerClass *service)
 {
@@ -312,20 +299,6 @@ tracker_class_set_uri (TrackerClass *service,
        }
 }
 
-void
-tracker_class_set_count (TrackerClass *service,
-                         gint          value)
-{
-       TrackerClassPrivate *priv;
-
-       g_return_if_fail (TRACKER_IS_CLASS (service));
-
-       priv = tracker_class_get_instance_private (service);
-
-       priv->count = value;
-}
-
-
 void
 tracker_class_set_id (TrackerClass *service,
                       gint          value)
diff --git a/src/libtracker-data/tracker-class.h b/src/libtracker-data/tracker-class.h
index 1c01e8914..004c6660c 100644
--- a/src/libtracker-data/tracker-class.h
+++ b/src/libtracker-data/tracker-class.h
@@ -53,7 +53,6 @@ GType             tracker_class_get_type               (void) G_GNUC_CONST;
 TrackerClass *    tracker_class_new                    (gboolean             use_gvdb);
 const gchar *     tracker_class_get_uri                (TrackerClass        *service);
 const gchar *     tracker_class_get_name               (TrackerClass        *service);
-gint              tracker_class_get_count              (TrackerClass        *service);
 gint              tracker_class_get_id                 (TrackerClass        *service);
 gboolean          tracker_class_get_is_new             (TrackerClass        *service);
 gboolean          tracker_class_get_db_schema_changed  (TrackerClass        *service);
@@ -66,8 +65,6 @@ TrackerClass    **tracker_class_get_last_super_classes (TrackerClass        *ser
 
 void              tracker_class_set_uri                (TrackerClass        *service,
                                                         const gchar         *value);
-void              tracker_class_set_count              (TrackerClass        *service,
-                                                        gint                 value);
 void              tracker_class_add_super_class        (TrackerClass        *service,
                                                         TrackerClass        *value);
 void              tracker_class_add_domain_index       (TrackerClass        *service,
diff --git a/src/libtracker-data/tracker-data-update.c b/src/libtracker-data/tracker-data-update.c
index c2bb92191..949bb9dd9 100644
--- a/src/libtracker-data/tracker-data-update.c
+++ b/src/libtracker-data/tracker-data-update.c
@@ -54,10 +54,6 @@ struct _TrackerDataUpdateBuffer {
        /* string -> TrackerDataUpdateBufferGraph */
        GPtrArray *graphs;
 
-       /* the following two fields are valid per sqlite transaction, not just for same subject */
-       /* TrackerClass -> integer */
-       GHashTable *class_counts;
-
 #if HAVE_TRACKER_FTS
        gboolean fts_ever_updated;
 #endif
@@ -749,25 +745,6 @@ statement_bind_gvalue (TrackerDBStatement *stmt,
        }
 }
 
-static void
-add_class_count (TrackerData  *data,
-                 TrackerClass *class,
-                 gint          count)
-{
-       gint old_count_entry;
-
-       tracker_class_set_count (class, tracker_class_get_count (class) + count);
-
-       /* update class_counts table so that the count change can be reverted in case of rollback */
-       if (!data->update_buffer.class_counts) {
-               data->update_buffer.class_counts = g_hash_table_new (g_direct_hash, g_direct_equal);
-       }
-
-       old_count_entry = GPOINTER_TO_INT (g_hash_table_lookup (data->update_buffer.class_counts, class));
-       g_hash_table_insert (data->update_buffer.class_counts, class,
-                            GINT_TO_POINTER (old_count_entry + count));
-}
-
 static void
 tracker_data_resource_buffer_flush (TrackerData                      *data,
                                     TrackerDataUpdateBufferResource  *resource,
@@ -851,10 +828,6 @@ tracker_data_resource_buffer_flush (TrackerData                      *data,
                                        return;
                                }
 
-                               if (table->class) {
-                                       add_class_count (data, table->class, -1);
-                               }
-
                                /* remove row from class table */
                                stmt = tracker_db_interface_create_statement (iface, 
TRACKER_DB_STATEMENT_CACHE_TYPE_UPDATE, &actual_error,
                                                                              "DELETE FROM \"%s\".\"%s\" 
WHERE ID = ?",
@@ -1090,24 +1063,6 @@ tracker_data_update_buffer_clear (TrackerData *data)
 #if HAVE_TRACKER_FTS
        data->update_buffer.fts_ever_updated = FALSE;
 #endif
-
-       if (data->update_buffer.class_counts) {
-               /* revert class count changes */
-
-               GHashTableIter iter;
-               TrackerClass *class;
-               gpointer count_ptr;
-
-               g_hash_table_iter_init (&iter, data->update_buffer.class_counts);
-               while (g_hash_table_iter_next (&iter, (gpointer*) &class, &count_ptr)) {
-                       gint count;
-
-                       count = GPOINTER_TO_INT (count_ptr);
-                       tracker_class_set_count (class, tracker_class_get_count (class) - count);
-               }
-
-               g_hash_table_remove_all (data->update_buffer.class_counts);
-       }
 }
 
 static void
@@ -1150,8 +1105,6 @@ cache_create_service_decomposed (TrackerData  *data,
        cache_insert_value (data, "rdfs:Resource_rdf:type", "rdf:type",
                            &gvalue, TRUE, FALSE, FALSE);
 
-       add_class_count (data, cl, 1);
-
        if (data->insert_callbacks) {
                guint n;
 
@@ -2084,8 +2037,6 @@ cache_delete_resource_type_full (TrackerData  *data,
                                error = NULL;
                        }
                }
-
-               add_class_count (data, class, -1);
        } else {
                cache_delete_row (data, class);
        }
@@ -2995,12 +2946,6 @@ tracker_data_commit_transaction (TrackerData  *data,
        data->in_transaction = FALSE;
        data->in_ontology_transaction = FALSE;
 
-       if (data->update_buffer.class_counts) {
-               /* successful transaction, no need to rollback class counts,
-                  so remove them */
-               g_hash_table_remove_all (data->update_buffer.class_counts);
-       }
-
 #if HAVE_TRACKER_FTS
        if (data->update_buffer.fts_ever_updated) {
                data->update_buffer.fts_ever_updated = FALSE;
diff --git a/src/tracker-store/tracker-statistics.vala b/src/tracker-store/tracker-statistics.vala
index e7f9a010c..407412876 100644
--- a/src/tracker-store/tracker-statistics.vala
+++ b/src/tracker-store/tracker-statistics.vala
@@ -21,48 +21,46 @@
 public class Tracker.Statistics : Object {
        public const string PATH = "/org/freedesktop/Tracker1/Statistics";
 
-       static bool initialized;
+       static GLib.HashTable<Tracker.Class, int> class_counts;
 
        [DBus (signature = "aas")]
        public new Variant get (BusName sender) throws GLib.Error {
                var request = DBusRequest.begin (sender, "Statistics.Get");
                var data_manager = Tracker.Main.get_data_manager ();
                var ontologies = data_manager.get_ontologies ();
+               var iface = data_manager.get_db_interface ();
 
-               if (!initialized) {
-                       var iface = data_manager.get_db_interface ();
+               class_counts = new HashTable<Tracker.Class, int> (direct_hash, direct_equal);
 
-                       foreach (var cl in ontologies.get_classes ()) {
-                               /* xsd classes do not derive from rdfs:Resource and do not use separate 
tables */
-                               if (!cl.name.has_prefix ("xsd:")) {
-                                       /* update statistics */
-                                       var stmt = iface.create_statement (DBStatementCacheType.NONE,
-                                                                          "SELECT COUNT(1) FROM \"%s\"",
-                                                                           cl.name);
+               foreach (var cl in ontologies.get_classes ()) {
+                       /* xsd classes do not derive from rdfs:Resource and do not use separate tables */
+                       if (!cl.name.has_prefix ("xsd:")) {
+                               /* update statistics */
+                               var stmt = iface.create_statement (DBStatementCacheType.NONE,
+                                                                  "SELECT COUNT(1) FROM \"%s\"",
+                                                                  cl.name);
 
-                                       var stat_cursor = stmt.start_cursor ();
-                                       if (stat_cursor.next ()) {
-                                               cl.count = (int) stat_cursor.get_integer (0);
-                                       } else {
-                                               warning ("Unable to query instance count for class %s", 
cl.name);
-                                       }
+                               var stat_cursor = stmt.start_cursor ();
+                               if (stat_cursor.next ()) {
+                                       class_counts.insert (cl, (int) stat_cursor.get_integer (0));
+                               } else {
+                                       warning ("Unable to query instance count for class %s", cl.name);
                                }
                        }
-
-                       initialized = true;
                }
 
                var builder = new VariantBuilder ((VariantType) "aas");
 
                foreach (var cl in ontologies.get_classes ()) {
-                       if (cl.count == 0) {
+                       int count = class_counts.lookup (cl);
+                       if (count == 0) {
                                /* skip classes without resources */
                                continue;
                        }
 
                        builder.open ((VariantType) "as");
                        builder.add ("s", cl.name);
-                       builder.add ("s", cl.count.to_string ());
+                       builder.add ("s", count.to_string ());
                        builder.close ();
                }