Ref all cached accessibles before querying them for GetItems

It is possible, at least in theory, that querying one accessible could
have the side effect of another accessible being dereferenced. If this
results in the accessible being finalized, then this would likely cause
a crash when potentially iterating over the newly-finalized object.

Hopefully fixes http://bugzilla.gnome.org/show_bug.cgi?id=664822

diff --git a/atk-adaptor/adaptors/cache-adaptor.c b/atk-adaptor/adaptors/cache-adaptor.c
index e221920..4f647a1 100644 (file)
--- a/atk-adaptor/adaptors/cache-adaptor.c
+++ b/atk-adaptor/adaptors/cache-adaptor.c
@@ -80,8 +80,6 @@ append_cache_item (AtkObject * obj, gpointer data)
   const char *name, *desc;
   dbus_uint32_t role;
 
-  g_object_ref (G_OBJECT (obj));
-
   set = atk_object_ref_state_set (obj);
   {
     AtkObject *application, *parent;
@@ -216,11 +214,16 @@ append_cache_item (AtkObject * obj, gpointer data)
   }
   dbus_message_iter_close_container (iter_array, &iter_struct);
   g_object_unref (set);
-  g_object_unref (obj);
 }
 
 /*---------------------------------------------------------------------------*/
 
+static void
+ref_accessible_hf (gpointer key, gpointer obj_data, gpointer data)
+{
+  g_object_ref (key);
+}
+
 /* For use as a GHFunc */
 static void
 append_accessible_hf (gpointer key, gpointer obj_data, gpointer data)
@@ -230,6 +233,12 @@ append_accessible_hf (gpointer key, gpointer obj_data, gpointer data)
     append_cache_item (ATK_OBJECT (key), data);
 }
 
+static void
+unref_accessible_hf (gpointer key, gpointer obj_data, gpointer data)
+{
+  g_object_unref (key);
+}
+
 /*---------------------------------------------------------------------------*/
 
 static void
@@ -267,7 +276,9 @@ emit_cache_add (SpiCache *cache, GObject * obj)
       DBusMessageIter iter;
 
       dbus_message_iter_init_append (message, &iter);
+      g_object_ref (accessible);
       append_cache_item (accessible, &iter);
+      g_object_unref (accessible);
 
       dbus_connection_send (spi_global_app_data->bus, message, NULL);
 
@@ -300,7 +311,9 @@ impl_GetItems (DBusConnection * bus, DBusMessage * message, void *user_data)
   dbus_message_iter_init_append (reply, &iter);
   dbus_message_iter_open_container (&iter, DBUS_TYPE_ARRAY,
                                     SPI_CACHE_ITEM_SIGNATURE, &iter_array);
+  spi_cache_foreach (spi_global_cache, ref_accessible_hf, NULL);
   spi_cache_foreach (spi_global_cache, append_accessible_hf, &iter_array);
+  spi_cache_foreach (spi_global_cache, unref_accessible_hf, NULL);
   dbus_message_iter_close_container (&iter, &iter_array);
   return reply;
 }