[gtk+] Make gtk_tree_model_foreach robust

[Matthias Clasen <matthiasc src gnome org>]

commit 1ed5bd07bbe61f8cff5ca122e94d90c8ec97075c
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Dec 9 00:41:11 2014 -0500

    Make gtk_tree_model_foreach robust
    
    Make gtk_tree_model_foreach safe for callbacks that modify
    the model, even if the model does not have persistent iters.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=722781

 gtk/gtktreemodel.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtktreemodel.c b/gtk/gtktreemodel.c
index 3906562..8bbf55d 100644
--- a/gtk/gtktreemodel.c
+++ b/gtk/gtktreemodel.c
@@ -1969,6 +1969,10 @@ gtk_tree_model_foreach_helper (GtkTreeModel            *model,
                                GtkTreeModelForeachFunc  func,
                                gpointer                 user_data)
 {
+  gboolean iters_persist;
+
+  iters_persist = gtk_tree_model_get_flags (model) & GTK_TREE_MODEL_ITERS_PERSIST;
+
   do
     {
       GtkTreeIter child;
@@ -1976,6 +1980,12 @@ gtk_tree_model_foreach_helper (GtkTreeModel            *model,
       if ((* func) (model, path, iter, user_data))
         return TRUE;
 
+      if (!iters_persist)
+        {
+          if (!gtk_tree_model_get_iter (model, iter, path))
+            return TRUE;
+        }
+
       if (gtk_tree_model_iter_children (model, &child, iter))
         {
           gtk_tree_path_down (path);