[mutter/wip/carlosg/xwayland-on-demand: 13/28] x11: Add meta_x11_get_display_name() function

[Carlos Garnacho <carlosg src gnome org>]

commit 47c4867ade7980477bd9713f02061283aaba2dd7
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri May 24 19:51:00 2019 +0200

    x11: Add meta_x11_get_display_name() function
    
    Instead of poking the DISPLAY envvar at places.

 src/core/meta-launch-context.c     |  2 +-
 src/x11/meta-x11-display-private.h |  2 ++
 src/x11/meta-x11-display.c         | 21 ++++++++++++++++++++-
 3 files changed, 23 insertions(+), 2 deletions(-)
---
diff --git a/src/core/meta-launch-context.c b/src/core/meta-launch-context.c
index 984338c1b0..8cc052452f 100644
--- a/src/core/meta-launch-context.c
+++ b/src/core/meta-launch-context.c
@@ -114,7 +114,7 @@ meta_launch_context_constructed (GObject *object)
 
   G_OBJECT_CLASS (meta_launch_context_parent_class)->constructed (object);
 
-  x11_display = getenv ("DISPLAY");
+  x11_display = meta_x11_get_display_name ();
   wayland_display = getenv ("WAYLAND_DISPLAY");
 
   if (x11_display)
diff --git a/src/x11/meta-x11-display-private.h b/src/x11/meta-x11-display-private.h
index 3f545ce283..1b38e3c30f 100644
--- a/src/x11/meta-x11-display-private.h
+++ b/src/x11/meta-x11-display-private.h
@@ -249,4 +249,6 @@ void meta_x11_display_set_input_focus (MetaX11Display *x11_display,
                                        Window          xwindow,
                                        guint32         timestamp);
 
+const gchar * meta_x11_get_display_name (void);
+
 #endif /* META_X11_DISPLAY_PRIVATE_H */
diff --git a/src/x11/meta-x11-display.c b/src/x11/meta-x11-display.c
index e9428e54d6..def878d2c4 100644
--- a/src/x11/meta-x11-display.c
+++ b/src/x11/meta-x11-display.c
@@ -988,6 +988,25 @@ meta_set_gnome_wm_keybindings (const char *wm_keybindings)
   gnome_wm_keybindings = wm_keybindings;
 }
 
+const gchar *
+meta_x11_get_display_name (void)
+{
+#ifdef HAVE_WAYLAND
+  if (meta_is_wayland_compositor ())
+    {
+      MetaWaylandCompositor *compositor;
+
+      compositor = meta_wayland_compositor_get_default ();
+
+      return meta_wayland_get_xwayland_display_name (compositor);
+    }
+  else
+#endif
+    {
+      return g_getenv ("DISPLAY");
+    }
+}
+
 gboolean
 meta_x11_init_gdk_display (GError **error)
 {
@@ -996,7 +1015,7 @@ meta_x11_init_gdk_display (GError **error)
   const char *gdk_gl_env = NULL;
   Display *xdisplay;
 
-  xdisplay_name = g_getenv ("DISPLAY");
+  xdisplay_name = meta_x11_get_display_name ();
   if (!xdisplay_name)
     {
       g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,