[gnome-control-center] CcRRLabeler: don't crash when not running under X

[Giovanni Campagna <gcampagna src gnome org>]

commit 4c85135171d2ee8240352074f92a217d62972b69
Author: Giovanni Campagna <gcampagn redhat com>
Date:   Fri Jul 26 15:54:59 2013 +0200

    CcRRLabeler: don't crash when not running under X
    
    If running under wayland, we can't use an X property notify
    to look at workarea changes.
    Currently, workarea is not part of the wayland protocol, so don't
    bother and just don't crash.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=705573

 panels/display/cc-rr-labeler.c |   35 +++++++++++++++++++++++++----------
 1 files changed, 25 insertions(+), 10 deletions(-)
---
diff --git a/panels/display/cc-rr-labeler.c b/panels/display/cc-rr-labeler.c
index 9773be4..ea8a7fd 100644
--- a/panels/display/cc-rr-labeler.c
+++ b/panels/display/cc-rr-labeler.c
@@ -29,11 +29,13 @@
 #include <glib/gi18n-lib.h>
 #include <gtk/gtk.h>
 
+#ifdef GDK_WINDOWING_X11
 #include <X11/Xproto.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/Xatom.h>
 #include <gdk/gdkx.h>
+#endif
 
 #include "cc-rr-labeler.h"
 
@@ -46,7 +48,10 @@ struct _CcRRLabelerPrivate {
        GtkWidget **windows;
 
        GdkScreen  *screen;
+       gboolean    has_event_filter;
+#ifdef GDK_WINDOWING_X11
        Atom        workarea_atom;
+#endif
 };
 
 enum {
@@ -60,6 +65,7 @@ G_DEFINE_TYPE (CcRRLabeler, cc_rr_labeler, G_TYPE_OBJECT);
 static void cc_rr_labeler_finalize (GObject *object);
 static void setup_from_config (CcRRLabeler *labeler);
 
+#ifdef GDK_WINDOWING_X11
 static GdkFilterReturn
 screen_xevent_filter (GdkXEvent      *xevent,
                      GdkEvent       *event,
@@ -80,6 +86,7 @@ screen_xevent_filter (GdkXEvent      *xevent,
 
        return GDK_FILTER_CONTINUE;
 }
+#endif
 
 static void
 cc_rr_labeler_init (CcRRLabeler *labeler)
@@ -88,15 +95,21 @@ cc_rr_labeler_init (CcRRLabeler *labeler)
 
        labeler->priv = G_TYPE_INSTANCE_GET_PRIVATE (labeler, GNOME_TYPE_RR_LABELER, CcRRLabelerPrivate);
 
-       labeler->priv->workarea_atom = XInternAtom (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()),
-                                                   "_NET_WORKAREA",
-                                                   True);
-
        labeler->priv->screen = gdk_screen_get_default ();
-       /* code is not really designed to handle multiple screens so *shrug* */
-       gdkwindow = gdk_screen_get_root_window (labeler->priv->screen);
-       gdk_window_add_filter (gdkwindow, (GdkFilterFunc) screen_xevent_filter, labeler);
-       gdk_window_set_events (gdkwindow, gdk_window_get_events (gdkwindow) | GDK_PROPERTY_CHANGE_MASK);
+#ifdef GDK_WINDOWING_X11
+       if (GDK_IS_X11_DISPLAY (gdk_display_get_default ())) {
+               labeler->priv->workarea_atom = XInternAtom (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()),
+                                                           "_NET_WORKAREA",
+                                                           True);
+
+               /* code is not really designed to handle multiple screens so *shrug* */
+               gdkwindow = gdk_screen_get_root_window (labeler->priv->screen);
+               gdk_window_add_filter (gdkwindow, (GdkFilterFunc) screen_xevent_filter, labeler);
+               gdk_window_set_events (gdkwindow, gdk_window_get_events (gdkwindow) | 
GDK_PROPERTY_CHANGE_MASK);
+
+               labeler->priv->has_event_filter = TRUE;
+       }
+#endif
 }
 
 static void
@@ -152,8 +165,10 @@ cc_rr_labeler_finalize (GObject *object)
 
        labeler = CC_RR_LABELER (object);
 
-       gdkwindow = gdk_screen_get_root_window (labeler->priv->screen);
-       gdk_window_remove_filter (gdkwindow, (GdkFilterFunc) screen_xevent_filter, labeler);
+       if (labeler->priv->has_event_filter) {
+               gdkwindow = gdk_screen_get_root_window (labeler->priv->screen);
+               gdk_window_remove_filter (gdkwindow, (GdkFilterFunc) screen_xevent_filter, labeler);
+       }
 
        if (labeler->priv->config != NULL) {
                g_object_unref (labeler->priv->config);