[gtk+] GtkWidget: Use gdk_window_get_children_for_user_data

[Alexander Larsson <alexl src gnome org>]

commit 0600d3d7e4c85eefa479d9735df37af707a31438
Author: Alexander Larsson <alexl redhat com>
Date:   Fri May 3 10:42:40 2013 +0200

    GtkWidget: Use gdk_window_get_children_for_user_data
    
    This makes iterating over the children a lot faster, as we're
    not doing lots of intra-library calls and type checks. We're still
    in some sence O(n^2) since we iterate over each child window for each
    widget, but the profiles look much better.

 gtk/gtkwidget.c |   55 +++++++++++++++++++++++++------------------------------
 1 files changed, 25 insertions(+), 30 deletions(-)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 19e026a..2139d7b 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -6402,7 +6402,7 @@ _gtk_widget_draw_windows (GdkWindow *window,
   cairo_pattern_t *pattern;
   gboolean do_clip;
   GtkWidget *widget = NULL;
-  GList *l;
+  GList *children, *l;
   int x, y;
 
   if (!gdk_window_is_viewable (window))
@@ -6438,29 +6438,26 @@ _gtk_widget_draw_windows (GdkWindow *window,
       _gtk_widget_draw_internal (widget, cr, do_clip, window);
       cairo_restore (cr);
 
-      for (l = g_list_last (gdk_window_peek_children (window));
-          l != NULL;
-          l = l->prev)
+      children = gdk_window_get_children_with_user_data (window, widget);
+      for (l = children; l != NULL; l = l->next)
        {
          GdkWindow *child_window = l->data;
-         gpointer child_data;
          GdkWindowType type;
          int wx, wy;
 
-         type = gdk_window_get_window_type (child_window);
          if (!gdk_window_is_visible (child_window) ||
-             gdk_window_is_input_only (child_window) ||
-             type == GDK_WINDOW_OFFSCREEN ||
+             gdk_window_is_input_only (child_window))
+           continue;
+
+         type = gdk_window_get_window_type (child_window);
+         if (type == GDK_WINDOW_OFFSCREEN ||
              type == GDK_WINDOW_FOREIGN)
            continue;
 
-         gdk_window_get_user_data (child_window, &child_data);
-         if (child_data == (gpointer)widget)
-           {
-             gdk_window_get_position (child_window, &wx, &wy);
-             _gtk_widget_draw_windows (child_window, cr, wx,wy);
-           }
+         gdk_window_get_position (child_window, &wx, &wy);
+         _gtk_widget_draw_windows (child_window, cr, wx,wy);
        }
+      g_list_free (children);
     }
 
   cairo_restore (cr);
@@ -6471,8 +6468,7 @@ _gtk_widget_draw (GtkWidget *widget,
                  cairo_t   *cr)
 {
   GdkWindow *window, *child_window;
-  gpointer child_data;
-  GList *l;
+  GList *children, *l;
   int wx, wy;
   gboolean push_group;
   GdkWindowType type;
@@ -6520,27 +6516,26 @@ _gtk_widget_draw (GtkWidget *widget,
 
       /* But, it may also have child windows in the parent which we should
        * draw (after having drawn on the parent) */
-      for (l = g_list_last (gdk_window_peek_children (window));
-          l != NULL;
-          l = l->prev)
+      children = gdk_window_get_children_with_user_data (window, widget);
+      for (l = children; l != NULL; l = l->next)
        {
          child_window = l->data;
-         type = gdk_window_get_window_type (child_window);
+
          if (!gdk_window_is_visible (child_window) ||
-             gdk_window_is_input_only (child_window) ||
-             type == GDK_WINDOW_OFFSCREEN ||
+             gdk_window_is_input_only (child_window))
+           continue;
+
+         type = gdk_window_get_window_type (child_window);
+         if (type == GDK_WINDOW_OFFSCREEN ||
              type == GDK_WINDOW_FOREIGN)
            continue;
 
-         gdk_window_get_user_data (child_window, &child_data);
-         if (child_data == (gpointer)widget)
-           {
-             gdk_window_get_position (child_window, &wx, &wy);
-             _gtk_widget_draw_windows (child_window, cr,
-                                       wx - widget->priv->allocation.x,
-                                       wy - widget->priv->allocation.y);
-           }
+         gdk_window_get_position (child_window, &wx, &wy);
+         _gtk_widget_draw_windows (child_window, cr,
+                                   wx - widget->priv->allocation.x,
+                                   wy - widget->priv->allocation.y);
        }
+      g_list_free (children);
     }
 
   if (push_group)