Fix possible leaks in graph's current design

[babeltrace.git] / lib / graph / connection.c

diff --git a/lib/graph/connection.c b/lib/graph/connection.c
index a9a5f9db667b2a86b0e8e8e117ab1aefe518f4a1..feed59556247c562c40d2149cf38cae7e20263f7 100644 (file)
--- a/lib/graph/connection.c
+++ b/lib/graph/connection.c
@@ -43,6 +43,37 @@ void bt_connection_destroy(struct bt_object *obj)
 {
        struct bt_connection *connection = container_of(obj,
                        struct bt_connection, base);
+       size_t i;
+
+       /*
+        * Make sure that each notification iterator which was created
+        * for this connection is finalized before we destroy it. Once a
+        * notification iterator is finalized, all its method return
+        * NULL or the BT_NOTIFICATION_ITERATOR_STATUS_CANCELED status.
+        *
+        * Because connections are destroyed before components within a
+        * graph, this ensures that notification iterators are always
+        * finalized before their upstream component.
+        */
+       if (connection->iterators) {
+               for (i = 0; i < connection->iterators->len; i++) {
+                       struct bt_notification_iterator *iterator =
+                               g_ptr_array_index(connection->iterators, i);
+
+                       bt_notification_iterator_finalize(iterator);
+
+                       /*
+                        * Make sure this iterator does not try to
+                        * remove itself from this connection's
+                        * iterators on destruction because this
+                        * connection won't exist anymore.
+                        */
+                       bt_notification_iterator_set_connection(iterator,
+                               NULL);
+               }
+
+               g_ptr_array_free(connection->iterators, TRUE);
+       }
 
        /*
         * No bt_put on ports as a connection only holds _weak_ references
@@ -78,6 +109,12 @@ struct bt_connection *bt_connection_create(
        }
 
        bt_object_init(connection, bt_connection_destroy);
+       connection->iterators = g_ptr_array_new();
+       if (!connection->iterators) {
+               BT_PUT(connection);
+               goto end;
+       }
+
        /* Weak references are taken, see comment in header. */
        connection->upstream_port = upstream_port;
        connection->downstream_port = downstream_port;
@@ -165,7 +202,6 @@ bt_private_connection_create_notification_iterator(
        }
 
        connection = bt_connection_from_private(private_connection);
-
        if (!connection->upstream_port || !connection->downstream_port) {
                goto error;
        }
@@ -189,7 +225,7 @@ bt_private_connection_create_notification_iterator(
        }
 
        iterator = bt_notification_iterator_create(upstream_component,
-               upstream_port, notification_types);
+               upstream_port, notification_types, connection);
        if (!iterator) {
                goto error;
        }
@@ -230,6 +266,7 @@ bt_private_connection_create_notification_iterator(
                goto error;
        }
 
+       g_ptr_array_add(connection->iterators, iterator);
        goto end;
 
 error:
@@ -239,3 +276,10 @@ end:
        bt_put(upstream_component);
        return iterator;
 }
+
+BT_HIDDEN
+void bt_connection_remove_iterator(struct bt_connection *conn,
+               struct bt_notification_iterator *iterator)
+{
+       g_ptr_array_remove(conn->iterators, iterator);
+}