Be more careful when freeing ui manager nodes

https://bugzilla.redhat.com//show_bug.cgi?id=812035 has
a stacktrace that shows recursion via
free_node -> unref -> dispose -> ui manager api
which ends in a crash, since we run free_node over the entire
tree and it leaves lots of dangling pointers behind.
So, better be careful by setting all pointers to NULL after
freeing them.

diff --git a/gtk/gtkuimanager.c b/gtk/gtkuimanager.c
index bb0137f8b8d7c05d60f34bf436f291d5b40ae84c..c80df7cd3ac7ec406041683b0e336aa6a8071e3a 100644 (file)
--- a/gtk/gtkuimanager.c
+++ b/gtk/gtkuimanager.c
@@ -1396,17 +1396,16 @@ static gboolean
 free_node (GNode *node)
 {
   Node *info = NODE_INFO (node);
-  
+
   g_list_free_full (info->uifiles, node_ui_reference_free);
+  info->uifiles = NULL;
 
-  if (info->action)
-    g_object_unref (info->action);
-  if (info->proxy)
-    g_object_unref (info->proxy);
-  if (info->extra)
-    g_object_unref (info->extra);
-  g_free (info->name);
+  g_clear_object (&info->action);
+  g_clear_object (&info->proxy);
+  g_clear_object (&info->extra);
+  g_clear_pointer (&info->name, g_free);
   g_slice_free (Node, info);
+  node->data = NULL;
 
   return FALSE;
 }