[cogl/cogl-1.18] cogl-winsys-egl-wayland: Report an error if we can't find the globals we need

[Neil Roberts <nroberts src gnome org>]

commit 76cdaabc153ebba44f7026d4c6a5a93679bd1497
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Thu Feb 6 13:48:41 2014 -0500

    cogl-winsys-egl-wayland: Report an error if we can't find the globals we need
    
    Instead of spinning forever, do a roundtrip, which guarantees that the
    global messages have been sent by the time we read the sync message.
    
    If the proper globals aren't initialized yet, error out immediately. This
    does mean that users can't use CoglOnscreen with foreign custom surface
    types without xdg_shell, but when a use case comes for this, we'll
    investigate then...
    
    Reviewed-by: Neil Roberts <neil linux intel com>
    (cherry picked from commit af9057d35f331e2c9509958fb40627917c477b80)

 cogl/winsys/cogl-winsys-egl-wayland.c |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)
---
diff --git a/cogl/winsys/cogl-winsys-egl-wayland.c b/cogl/winsys/cogl-winsys-egl-wayland.c
index dd1a1b1..c631080 100644
--- a/cogl/winsys/cogl-winsys-egl-wayland.c
+++ b/cogl/winsys/cogl-winsys-egl-wayland.c
@@ -273,13 +273,17 @@ _cogl_winsys_renderer_connect (CoglRenderer *renderer,
 
   /*
    * Ensure that that we've received the messages setting up the
-   * compostor and shell object. This is better than just
-   * wl_display_iterate since it will always ensure that something
-   * is available to be read
+   * compostor and shell object.
    */
-  while (!(wayland_renderer->wayland_compositor &&
-           wayland_renderer->wayland_shell))
-    wl_display_roundtrip (wayland_renderer->wayland_display);
+  wl_display_roundtrip (wayland_renderer->wayland_display);
+  if (!wayland_renderer->wayland_compositor || !wayland_renderer->wayland_shell)
+    {
+      _cogl_set_error (error,
+                       COGL_WINSYS_ERROR,
+                       COGL_WINSYS_ERROR_INIT,
+                       "Unable to find wl_compositor or wl_shell");
+      goto error;
+    }
 
   egl_renderer->edpy =
     eglGetDisplay ((EGLNativeDisplayType) wayland_renderer->wayland_display);