[systemd-devel] [PATCH] event: clear pending-state when re-arming timers

[Lennart Poettering]

On Wed, 20.11.13 07:59, David Herrmann (dh.herrmann at gmail.com) wrote:

> If a timer fires and is marked pending, but an application re-arms it
> before it is dispatched, we now clear the pending state.
> 
> This fixes a bug where an application arms a timer, which fires and is
> marked pending. But before it is dispatched, the application loses
> interest in it and disables it. Now if the timer is re-armed and
> re-enabled later, it will be immediately dispatched as it is still marked
> pending.
> 
> This behavior is unexpected, so avoid it by clearing pending state when
> re-arming timers. Note that applications have no way to clear pending
> state themselves, so there's no current workaround.

Same mistake was actually was actually in the handling of changing of
the accuracy and of IO events too. Fixed those too now.

When you push a patch please reply to the mail you posted on
systemd-devel (if you posted one) and simply say "Commited." or so, so
that it is easy for us to track what got already merged and what didn't!
Thanks!

> ---
>  src/libsystemd-bus/sd-event.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/src/libsystemd-bus/sd-event.c b/src/libsystemd-bus/sd-event.c
> index 0996316..d01e82d 100644
> --- a/src/libsystemd-bus/sd-event.c
> +++ b/src/libsystemd-bus/sd-event.c
> @@ -1241,6 +1241,7 @@ _public_ int sd_event_source_set_time(sd_event_source *s, uint64_t usec) {
>                  return 0;
>  
>          s->time.next = usec;
> +        source_set_pending(s, false);
>  
>          if (s->type == SOURCE_REALTIME) {
>                  prioq_reshuffle(s->event->realtime_earliest, s, &s->time.earliest_index);


Lennart

-- 
Lennart Poettering, Red Hat