/// <summary>
/// Remove 'subscription from the list of subscriptions that the observable has. Called when
/// subscriptions are disposed. Returns true if the subscription was removed.
/// </summary>
private bool Remove(AllListenerSubscription subscription)
{
lock (s_allListenersLock)
{
if (_subscriptions == subscription)
{
_subscriptions = subscription.Next;
return(true);
}
else if (_subscriptions != null)
{
for (var cur = _subscriptions; cur.Next != null; cur = cur.Next)
{
if (cur.Next == subscription)
{
cur.Next = cur.Next.Next;
return(true);
}
}
}
// Subscriber likely disposed multiple times
return(false);
}
}
public IDisposable Subscribe(IObserver <DiagnosticListener> observer)
{
lock (s_allListenersLock)
{
// Call back for each existing listener on the new callback (catch-up).
for (DiagnosticListener cur = s_allListeners; cur != null; cur = cur._next)
{
observer.OnNext(cur);
}
// Add the observer to the list of subscribers.
_subscriptions = new AllListenerSubscription(this, observer, _subscriptions);
return(_subscriptions);
}
}
/// <summary>
/// Remove 'subscription from the list of subscriptions that the observable has. Called when
/// subscriptions are disposed.
/// </summary>
private void Remove(AllListenerSubscription subscription)
{
lock (DefaultListener)
{
// Remove myself from the linked list.
if (_subscriptions == subscription)
{
_subscriptions = subscription.Next;
}
else
{
for (var cur = _subscriptions; cur.Next != null; cur = cur.Next)
{
if (cur.Next.Subscriber == this)
{
cur.Next = cur.Next.Next;
return;
}
}
Debug.Assert(false, "Could not find subscription in the AllListeners subscribers list");
}
}
}
internal AllListenerSubscription(AllListenerObservable owner, IObserver <DiagnosticListener> subscriber, AllListenerSubscription next)
{
this._owner = owner;
this.Subscriber = subscriber;
this.Next = next;
}