Improve tests for X error traps, fix two bugs

* don't lose track of previous X error handler
  if nested traps are pushed
* free any remaining traps when display
  is finalized

Test will fail unless bug 630032 is closed so
gdk_display_close() works.

https://bugzilla.gnome.org/show_bug.cgi?id=630033

2 files changed, 25 insertions, 3 deletions

diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index ea4e9914dc..3b82590e3a 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -1911,6 +1911,21 @@ gdk_display_x11_finalize (GObject *object)
 
   XCloseDisplay (display_x11->xdisplay);
 
+  /* error traps */
+  while (display_x11->error_traps != NULL)
+    {
+      GdkErrorTrap *trap = display_x11->error_traps->data;
+
+      display_x11->error_traps =
+        g_slist_delete_link (display_x11->error_traps,
+                             display_x11->error_traps);
+
+      if (trap->end_sequence == 0)
+        g_warning ("Display finalized with an unpopped error trap");
+
+      g_slice_free (GdkErrorTrap, trap);
+    }
+
   G_OBJECT_CLASS (_gdk_display_x11_parent_class)->finalize (object);
 }
 
diff --git a/gdk/x11/gdkmain-x11.c b/gdk/x11/gdkmain-x11.c
index 996715c75f..ca20f97304 100644
--- a/gdk/x11/gdkmain-x11.c
+++ b/gdk/x11/gdkmain-x11.c
@@ -62,7 +62,8 @@ struct _GdkPredicate
 };
 
 /* non-GDK previous error handler */
-static int (*_gdk_old_error_handler) (Display *, XErrorEvent *);
+typedef int (*GdkXErrorHandler) (Display *, XErrorEvent *);
+static GdkXErrorHandler _gdk_old_error_handler;
 /* number of times we've pushed the GDK error handler */
 static int _gdk_error_handler_push_count = 0;
 
@@ -386,13 +387,19 @@ gdk_x_error (Display	 *xdisplay,
 void
 _gdk_x11_error_handler_push (void)
 {
-  _gdk_old_error_handler = XSetErrorHandler (gdk_x_error);
+  GdkXErrorHandler previous;
+
+  previous = XSetErrorHandler (gdk_x_error);
 
   if (_gdk_error_handler_push_count > 0)
     {
-      if (_gdk_old_error_handler != gdk_x_error)
+      if (previous != gdk_x_error)
         g_warning ("XSetErrorHandler() called with a GDK error trap pushed. Don't do that.");
     }
+  else
+    {
+      _gdk_old_error_handler = previous;
+    }
 
   _gdk_error_handler_push_count += 1;
 }