compositor-wayland: strict surface create/destroy

Add safeguards to make it painfully obvious if we ever get the pairing
of wayland_backend_create_output_surface() and
wayland_backend_destroy_output_surface() wrong. Helps catching bugs.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Ian Ray <ian.ray@ge.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Acked-by: Derek Foreman <derekf@osg.samsung.com>

diff --git a/libweston/compositor-wayland.c b/libweston/compositor-wayland.c
index fbb04de..82e52b9 100644 (file)
--- a/libweston/compositor-wayland.c
+++ b/libweston/compositor-wayland.c
@@ -645,16 +645,25 @@ wayland_output_repaint_pixman(struct weston_output *output_base,
 static void
 wayland_backend_destroy_output_surface(struct wayland_output *output)
 {
-       if (output->parent.xdg_toplevel)
+       assert(output->parent.surface);
+
+       if (output->parent.xdg_toplevel) {
                zxdg_toplevel_v6_destroy(output->parent.xdg_toplevel);
+               output->parent.xdg_toplevel = NULL;
+       }
 
-       if (output->parent.xdg_surface)
+       if (output->parent.xdg_surface) {
                zxdg_surface_v6_destroy(output->parent.xdg_surface);
+               output->parent.xdg_surface = NULL;
+       }
 
-       if (output->parent.shell_surface)
+       if (output->parent.shell_surface) {
                wl_shell_surface_destroy(output->parent.shell_surface);
+               output->parent.shell_surface = NULL;
+       }
 
        wl_surface_destroy(output->parent.surface);
+       output->parent.surface = NULL;
 }
 
 static void
@@ -1139,6 +1148,8 @@ wayland_backend_create_output_surface(struct wayland_output *output)
 {
        struct wayland_backend *b = to_wayland_backend(output->base.compositor);
 
+       assert(!output->parent.surface);
+
        output->parent.surface =
                wl_compositor_create_surface(b->parent.compositor);
        if (!output->parent.surface)