[PATCH wayland] wayland-client : Fix duplicated proxy destroy

[Jonas Ådahl]

On Fri, Jul 31, 2015 at 04:04:14PM +0900, Elvis Lee wrote:
> proxy_destroy can be called twice by wl_proxy_destroy and wl_event_queue_release.
> In that case, wl_map_remove should be called only once for same object id.
> 
> Signed-off-by: Elvis Lee <kwangwoong.lee at lge.com>

Yepp. In 5c70c031 we started to destroy proxies when they were lingering
in a queue that was being released. But if such a proxy had been both
explicitly destroyed (with wl_proxy_destroy) and deleted via the
delete_id event but not be dispatched by the queue we'd now remove it
from the map twice.

However, I think we should rather do the same as when dispatching when
releasing from the queue, i.e:
 1. check whether the proxy had been destroyed (proxy->flags &
    WL_PROXY_FLAG_DESTROYED)
 2. decrease the reference count, and free if we are the last holder.

Calling "destroy_proxy" in queue_release I believe is incorrect; the
original idea with WL_PROXY_FLAG_DESTROYED was that it had been
destroyed via wl_proxy_destroy.


Jonas

> ---
>  src/wayland-client.c |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/src/wayland-client.c b/src/wayland-client.c
> index 6450b67..b087ed3 100644
> --- a/src/wayland-client.c
> +++ b/src/wayland-client.c
> @@ -405,6 +405,9 @@ wl_proxy_create_for_id(struct wl_proxy *factory,
>  void
>  proxy_destroy(struct wl_proxy *proxy)
>  {
> +	if (proxy->flags & WL_PROXY_FLAG_DESTROYED)
> +		goto unreference;
> +
>  	if (proxy->flags & WL_PROXY_FLAG_ID_DELETED)
>  		wl_map_remove(&proxy->display->objects, proxy->object.id);
>  	else if (proxy->object.id < WL_SERVER_ID_START)
> @@ -417,6 +420,7 @@ proxy_destroy(struct wl_proxy *proxy)
>  
>  	proxy->flags |= WL_PROXY_FLAG_DESTROYED;
>  
> +unreference:
>  	proxy->refcount--;
>  	if (!proxy->refcount)
>  		free(proxy);
> -- 
> 1.7.9.5
> 
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