# HG changeset patch
# User james
# Date 1151600340 0
# Node ID 20773f9b7bc02780c90072ebc620a05a0976cb29
# Parent  71532ccbd8e388b04fa0c468d63d8f58d53145ae
[xemacs-hg @ 2006-06-29 16:58:59 by james]
Check scrollbar instance data for NULLness before dereferencing.
<m31wt77vcf.fsf@jerrypc.cs.usu.edu>

diff -r 71532ccbd8e3 -r 20773f9b7bc0 src/ChangeLog
--- a/src/ChangeLog	Thu Jun 29 14:52:00 2006 +0000
+++ b/src/ChangeLog	Thu Jun 29 16:59:00 2006 +0000
@@ -1,3 +1,10 @@
+2006-06-29  Jerry James  <james@xemacs.org>
+
+	* scrollbar-gtk.c (gtk_free_scrollbar_instance): Compare
+	instance->scrollbar_data against NULL before using it.
+	* scrollbar-msw.c (mswindows_free_scrollbar_instance): Compare
+	sb->scrollbar_data against NULL before using it.
+
 2006-06-22  Jerry James  <james@xemacs.org>
 
 	* redisplay-gtk.c (gtk_output_display_block): Fix a Dynarr leak.
diff -r 71532ccbd8e3 -r 20773f9b7bc0 src/scrollbar-gtk.c
--- a/src/scrollbar-gtk.c	Thu Jun 29 14:52:00 2006 +0000
+++ b/src/scrollbar-gtk.c	Thu Jun 29 16:59:00 2006 +0000
@@ -56,14 +56,16 @@
 static void
 gtk_free_scrollbar_instance (struct scrollbar_instance *instance)
 {
-  if (SCROLLBAR_GTK_WIDGET (instance))
+  if (instance->scrollbar_data)
     {
-      gtk_widget_hide_all (SCROLLBAR_GTK_WIDGET (instance));
-      gtk_widget_destroy (SCROLLBAR_GTK_WIDGET (instance));
+      if (SCROLLBAR_GTK_WIDGET (instance))
+	{
+	  gtk_widget_hide_all (SCROLLBAR_GTK_WIDGET (instance));
+	  gtk_widget_destroy (SCROLLBAR_GTK_WIDGET (instance));
+	}
+
+      xfree (instance->scrollbar_data, void *);
     }
-
-  if (instance->scrollbar_data)
-    xfree (instance->scrollbar_data, void *);
 }
 
 /* A device method. */
diff -r 71532ccbd8e3 -r 20773f9b7bc0 src/scrollbar-msw.c
--- a/src/scrollbar-msw.c	Thu Jun 29 14:52:00 2006 +0000
+++ b/src/scrollbar-msw.c	Thu Jun 29 16:59:00 2006 +0000
@@ -90,17 +90,19 @@
 static void
 mswindows_free_scrollbar_instance (struct scrollbar_instance *sb)
 {
-  void *opaque =
-    (void *) qxeGetWindowLong (SCROLLBAR_MSW_HANDLE (sb), GWL_USERDATA);
-  Lisp_Object ptr;
+  if (sb->scrollbar_data)
+    {
+      void *opaque =
+	(void *) qxeGetWindowLong (SCROLLBAR_MSW_HANDLE (sb), GWL_USERDATA);
+      Lisp_Object ptr;
 
-  ptr = VOID_TO_LISP (opaque);
-  assert (OPAQUE_PTRP (ptr));
-  ptr = Fremhash (ptr, Vmswindows_scrollbar_instance_table);
-  assert (!NILP (ptr));
-  DestroyWindow (SCROLLBAR_MSW_HANDLE (sb));
-  if (sb->scrollbar_data)
-    xfree (sb->scrollbar_data, void *);
+      ptr = VOID_TO_LISP (opaque);
+      assert (OPAQUE_PTRP (ptr));
+      ptr = Fremhash (ptr, Vmswindows_scrollbar_instance_table);
+      assert (!NILP (ptr));
+      DestroyWindow (SCROLLBAR_MSW_HANDLE (sb));
+      xfree (sb->scrollbar_data, void *);
+    }
 }
 
 static void