[PATCH weston] desktop-shell: remove all running animations for a surface before fade out

[Derek Foreman]

The completion of the fade out animation destroys a surface which fires
the surface destroy signal.  Animations listen for the surface destroy
signal and destroy themselves as a response.

If there's an animation running on a surface when the fade out completes
the old animation will be removed from the animation list during the list
walk which can lead to a crash.

This can happen when a surface is mapped then quickly destroyed and the
fade out completes before the zoom in.

By removing all animations before starting the fade out we avoid this.

Signed-off-by: Derek Foreman <derekf at osg.samsung.com>
---
 desktop-shell/shell.c |  1 +
 src/animation.c       | 22 ++++++++++++++++++++++
 src/compositor.h      |  3 +++
 3 files changed, 26 insertions(+)

diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c
index f7c928e..38a3953 100644
--- a/desktop-shell/shell.c
+++ b/desktop-shell/shell.c
@@ -3592,6 +3592,7 @@ handle_resource_destroy(struct wl_listener *listener, void *data)
 	pixman_region32_fini(&shsurf->surface->input);
 	pixman_region32_init(&shsurf->surface->input);
 	if (shsurf->shell->win_close_animation_type == ANIMATION_FADE) {
+		weston_view_animation_cancel(shsurf->view);
 		weston_fade_run(shsurf->view, 1.0, 0.0, 300.0,
 				fade_out_done, shsurf);
 	} else {
diff --git a/src/animation.c b/src/animation.c
index 0febe41..578f73e 100644
--- a/src/animation.c
+++ b/src/animation.c
@@ -144,6 +144,28 @@ weston_view_animation_destroy(struct weston_view_animation *animation)
 	free(animation);
 }
 
+/** Cancel all running animations on a view
+ *
+ * \param view The view to cancel animations for.
+ *
+ * Walks the output animation list for the view's output and
+ * removes any animations for the view.
+ */
+WL_EXPORT void
+weston_view_animation_cancel(struct weston_view *view)
+{
+	struct weston_animation *animation, *next;
+
+	wl_list_for_each_safe(animation, next, &view->output->animation_list, link) {
+		struct weston_view_animation *wanim =
+			container_of(animation,
+				     struct weston_view_animation, animation);
+
+		if (wanim->view == view)
+			weston_view_animation_destroy(wanim);
+	}
+}
+
 static void
 handle_animation_view_destroy(struct wl_listener *listener, void *data)
 {
diff --git a/src/compositor.h b/src/compositor.h
index 5f49237..2a643c2 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -1489,6 +1489,9 @@ typedef	void (*weston_view_animation_done_func_t)(struct weston_view_animation *
 void
 weston_view_animation_destroy(struct weston_view_animation *animation);
 
+void
+weston_view_animation_cancel(struct weston_view *view);
+
 struct weston_view_animation *
 weston_zoom_run(struct weston_view *view, float start, float stop,
 		weston_view_animation_done_func_t done, void *data);
-- 
2.1.4