[clutter/fosdem-2012: 4/5] stash: only create TWSBuffer on surface attachment

[Robert Bragg <rbragg src gnome org>]

commit 6890bf522da87ea8e71d3bdc0177dce4f1d56f3c
Author: Robert Bragg <robert linux intel com>
Date:   Wed Jan 4 19:21:00 2012 +0000

    stash: only create TWSBuffer on surface attachment

 tests/interactive/test-wayland-surface.c |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/tests/interactive/test-wayland-surface.c b/tests/interactive/test-wayland-surface.c
index 015e0e2..632d024 100644
--- a/tests/interactive/test-wayland-surface.c
+++ b/tests/interactive/test-wayland-surface.c
@@ -207,7 +207,8 @@ tws_buffer_free (TWSBuffer *buffer)
 static void
 shm_buffer_created (struct wl_buffer *wayland_buffer)
 {
-  wayland_buffer->user_data = tws_buffer_new (wayland_buffer);
+  /* We ignore the buffer until it is attached to a surface */
+  wayland_buffer->user_data = NULL;
 }
 
 static void
@@ -220,6 +221,11 @@ shm_buffer_damaged (struct wl_buffer *wayland_buffer,
   TWSBuffer *buffer = wayland_buffer->user_data;
   GList *l;
 
+  /* We only have an associated TWSBuffer once the wayland buffer has
+   * been attached to a surface. */
+  if (!buffer)
+    return;
+
   for (l = buffer->surfaces_attached_to; l; l = l->next)
     {
       TWSSurface *surface = l->data;
@@ -234,6 +240,8 @@ shm_buffer_damaged (struct wl_buffer *wayland_buffer,
 static void
 shm_buffer_destroyed (struct wl_buffer *wayland_buffer)
 {
+  /* We only have an associated TWSBuffer once the wayland buffer has
+   * been attached to a surface. */
   if (wayland_buffer->user_data)
     tws_buffer_free ((TWSBuffer *)wayland_buffer->user_data);
 }
@@ -287,8 +295,6 @@ tws_surface_attach_buffer (struct wl_client *wayland_client,
 
   tws_surface_detach_buffer (surface);
 
-  /* XXX: we will have been notified of shm buffers already via the
-   * callbacks, but this will be the first we know of drm buffers */
   if (!buffer)
     {
       buffer = tws_buffer_new (wayland_buffer);