[tracker/miner-web] Fixed a big in delete_resource_description about usage of cursors

[Adrien Bustany <abustany src gnome org>]

commit e49456328c809eeeadb7164845f99a3395278d70
Author: Philip Van Hoof <philip codeminded be>
Date:   Wed Nov 4 10:41:13 2009 +0100

    Fixed a big in delete_resource_description about usage of cursors
    
    The outer query's cursor's statement was being reused by the inner queries'
    cursors' statements in some situations (where the outer query was identical to
    the inner queries). We don't yet support this.
    
    You can revert this patch as soon as we do support this.

 src/libtracker-data/tracker-data-update.c |   51 ++++++++++++++++++-----------
 1 files changed, 32 insertions(+), 19 deletions(-)
---
diff --git a/src/libtracker-data/tracker-data-update.c b/src/libtracker-data/tracker-data-update.c
index ee66110..26187c9 100644
--- a/src/libtracker-data/tracker-data-update.c
+++ b/src/libtracker-data/tracker-data-update.c
@@ -1682,15 +1682,18 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 {
 	TrackerDBInterface *iface;
 	TrackerDBStatement *stmt;
-	TrackerDBCursor    *cursor, *single_cursor, *multi_cursor;
+	TrackerDBResultSet *result_set, *single_result, *multi_result;
 	TrackerClass	   *class;
 	GString		   *sql;
 	TrackerProperty	  **properties, **property;
-	const gchar	   *class_uri, *value;
 	int		    i;
 	gboolean            first;
 	gint                resource_id;
 
+	/* We use result_sets instead of cursors here because it's possible
+	 * that otherwise the query of the outer cursor would be reused by the
+	 * cursors of the inner queries. */
+
 	resource_id = tracker_data_query_resource_id (uri);
 
 	iface = tracker_db_manager_get_db_interface ();
@@ -1699,18 +1702,23 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 
 	stmt = tracker_db_interface_create_statement (iface, "SELECT (SELECT Uri FROM \"rdfs:Resource\" WHERE ID = \"rdf:type\") FROM \"rdfs:Resource_rdf:type\" WHERE ID = ?");
 	tracker_db_statement_bind_int (stmt, 0, resource_id);
-	cursor = tracker_db_statement_start_cursor (stmt, NULL);
+	result_set = tracker_db_statement_execute (stmt, NULL);
 	g_object_unref (stmt);
 
-	if (cursor) {
-		while (tracker_db_cursor_iter_next (cursor)) {
-			class_uri = tracker_db_cursor_get_string (cursor, 0);
+	if (result_set) {
+		do {
+			gchar *class_uri;
+
+			tracker_db_result_set_get (result_set, 0, &class_uri, -1);
 
 			class = tracker_ontology_get_class_by_uri (class_uri);
+
 			if (class == NULL) {
 				g_warning ("Class '%s' not found in the ontology", class_uri);
+				g_free (class_uri);
 				continue;
 			}
+			g_free (class_uri);
 
 			/* retrieve single value properties for current class */
 
@@ -1734,13 +1742,12 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 				}
 			}
 
-			single_cursor = NULL;
+			single_result = NULL;
 			if (!first) {
 				g_string_append_printf (sql, " FROM \"%s\" WHERE ID = ?", tracker_class_get_name (class));
 				stmt = tracker_db_interface_create_statement (iface, "%s", sql->str);
 				tracker_db_statement_bind_int (stmt, 0, resource_id);
-				single_cursor = tracker_db_statement_start_cursor (stmt, NULL);
-				tracker_db_cursor_iter_next (single_cursor);
+				single_result = tracker_db_statement_execute (stmt, NULL);
 				g_object_unref (stmt);
 			}
 
@@ -1762,15 +1769,18 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 				}
 
 				if (!tracker_property_get_multiple_values (*property)) {
+					gchar *value;
+
 					/* single value property, value in single_result_set */
 
-					value = tracker_db_cursor_get_string (single_cursor, i++);
+					tracker_db_result_set_get (single_result, i++, &value, -1);
 
 					if (value) {
 						tracker_data_delete_statement (uri, 
 						                               tracker_property_get_uri (*property), 
 						                               value, 
 						                               error);
+						g_free (value);
 					}
 
 				} else {
@@ -1787,22 +1797,25 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 
 					stmt = tracker_db_interface_create_statement (iface, "%s", sql->str);
 					tracker_db_statement_bind_int (stmt, 0, resource_id);
-					multi_cursor = tracker_db_statement_start_cursor (stmt, NULL);
+					multi_result = tracker_db_statement_execute (stmt, NULL);
 					g_object_unref (stmt);
 
-					if (multi_cursor) {
-						while (tracker_db_cursor_iter_next (multi_cursor)) {
+					if (multi_result) {
+						do {
+							gchar *value;
 
-							value = tracker_db_cursor_get_string (multi_cursor, 0);
+							tracker_db_result_set_get (multi_result, 0, &value, -1);
 
 							tracker_data_delete_statement (uri, 
 							                               tracker_property_get_uri (*property), 
 							                               value,
 							                               NULL);
 
-						}
+							g_free (value);
+
+						} while (tracker_db_result_set_iter_next (multi_result));
 
-						g_object_unref (multi_cursor);
+						g_object_unref (multi_result);
 					}
 
 					g_string_free (sql, TRUE);
@@ -1810,12 +1823,12 @@ tracker_data_delete_resource_description (const gchar *uri, GError **error)
 			}
 
 			if (!first) {
-				g_object_unref (single_cursor);
+				g_object_unref (single_result);
 			}
 
-		}
+		} while (tracker_db_result_set_iter_next (result_set));
 
-		g_object_unref (cursor);
+		g_object_unref (result_set);
 	}
 }