[gtk+] Check if childs actually exists before using it

[Javier Jardón <jjardon src gnome org>]

commit c1a2ecc369b8419fdd835bb4d45b48982bfb6dab
Author: Javier Jardón <jjardon gnome org>
Date:   Thu Jul 22 16:43:23 2010 +0200

    Check if childs actually exists before using it
    
    Check seems to have gone lost during GtkBin sealing in commit 4427760b
    
    Fixes https://bugzilla.gnome.org/show_bug.cgi?id=624707

 gtk/gtkhandlebox.c       |    9 ++++++---
 gtk/gtkmenuitem.c        |    3 ++-
 gtk/gtkoffscreenwindow.c |    6 ++++--
 gtk/gtkplug.c            |    6 ++++--
 4 files changed, 16 insertions(+), 8 deletions(-)
---
diff --git a/gtk/gtkhandlebox.c b/gtk/gtkhandlebox.c
index 971ebd5..ead564c 100644
--- a/gtk/gtkhandlebox.c
+++ b/gtk/gtkhandlebox.c
@@ -378,7 +378,8 @@ gtk_handle_box_map (GtkWidget *widget)
   gtk_widget_set_mapped (widget, TRUE);
 
   child = gtk_bin_get_child (bin);
-  if (gtk_widget_get_visible (child) &&
+  if (child != NULL &&
+      gtk_widget_get_visible (child) &&
       !gtk_widget_get_mapped (child))
     gtk_widget_map (child);
 
@@ -652,7 +653,7 @@ gtk_handle_box_size_allocate (GtkWidget     *widget,
 			    widget->allocation.height);
 
 
-  if (gtk_widget_get_visible (child))
+  if (child != NULL && gtk_widget_get_visible (child))
     {
       GtkAllocation child_allocation;
       guint border_width;
@@ -919,6 +920,7 @@ gtk_handle_box_paint (GtkWidget      *widget,
   GtkHandleBox *hb = GTK_HANDLE_BOX (widget);
   GtkHandleBoxPriv *priv = hb->priv;
   GtkBin *bin = GTK_BIN (widget);
+  GtkWidget *child;
   gint width, height;
   GdkRectangle rect;
   GdkRectangle dest;
@@ -993,7 +995,8 @@ gtk_handle_box_paint (GtkWidget      *widget,
 			 event ? &event->area : area,
 			 handle_orientation);
 
-  if (gtk_widget_get_visible (gtk_bin_get_child (bin)))
+  child = gtk_bin_get_child (bin);
+  if (child != NULL && gtk_widget_get_visible (child))
     GTK_WIDGET_CLASS (gtk_handle_box_parent_class)->expose_event (widget, event);
 }
 
diff --git a/gtk/gtkmenuitem.c b/gtk/gtkmenuitem.c
index 580cb02..ded538c 100644
--- a/gtk/gtkmenuitem.c
+++ b/gtk/gtkmenuitem.c
@@ -973,7 +973,8 @@ gtk_menu_item_size_request (GtkWidget      *widget,
     requisition->height += 2 * horizontal_padding;
 
   child = gtk_bin_get_child (bin);
-  if (gtk_widget_get_visible (child))
+
+  if (child != NULL && gtk_widget_get_visible (child))
     {
       GtkRequisition child_requisition;
       
diff --git a/gtk/gtkoffscreenwindow.c b/gtk/gtkoffscreenwindow.c
index 30cc7a2..1c51abe 100644
--- a/gtk/gtkoffscreenwindow.c
+++ b/gtk/gtkoffscreenwindow.c
@@ -64,7 +64,8 @@ gtk_offscreen_window_size_request (GtkWidget *widget,
   requisition->height = border_width * 2;
 
   child = gtk_bin_get_child (bin);
-  if (gtk_widget_get_visible (child))
+
+  if (child != NULL && gtk_widget_get_visible (child))
     {
       GtkRequisition child_req;
 
@@ -103,7 +104,8 @@ gtk_offscreen_window_size_allocate (GtkWidget *widget,
                             allocation->height);
 
   child = gtk_bin_get_child (bin);
-  if (gtk_widget_get_visible (child))
+
+  if (child != NULL && gtk_widget_get_visible (child))
     {
       GtkAllocation  child_alloc;
 
diff --git a/gtk/gtkplug.c b/gtk/gtkplug.c
index 5bb003a..f1e2a19 100644
--- a/gtk/gtkplug.c
+++ b/gtk/gtkplug.c
@@ -710,7 +710,8 @@ gtk_plug_map (GtkWidget *widget)
       gtk_widget_set_mapped (widget, TRUE);
 
       child = gtk_bin_get_child (bin);
-      if (gtk_widget_get_visible (child) &&
+      if (child != NULL &&
+          gtk_widget_get_visible (child) &&
 	  !gtk_widget_get_mapped (child))
 	gtk_widget_map (child);
 
@@ -765,7 +766,8 @@ gtk_plug_size_allocate (GtkWidget     *widget,
 				allocation->width, allocation->height);
 
       child = gtk_bin_get_child (bin);
-      if (gtk_widget_get_visible (child))
+
+      if (child != NULL && gtk_widget_get_visible (child))
 	{
 	  GtkAllocation child_allocation;