Re: [libvirt] [PATCH 8/8] Only add the timer when a callback is registered

From: "Daniel P. Berrange" <berrange(a)redhat.com&gt; The lifetime of the virDomainEventState object is tied to the lifetime of the driver, which in stateless drivers is tied to the lifetime of the virConnectPtr. If we add & remove a timer when allocating/freeing the virDomainEventState object, we can get a situation where the timer still triggers once after virDomainEventState has been freed. The timeout callback can't keep a ref on the event state though, since that would be a circular reference. The trick is to only register the timer when a callback is registered with the event state & remove the timer when the callback is unregistered.