void AddInternal(IActorId id)
{
var hash = HashAlgorithm.ComputeHash(id.ToString());
lock (actors)
{
var index = actors.BinarySearch(KeyValuePair.New(hash, (IActorId)null), n => n.Key);
if (index >= 0) return;
actors.Insert(~index, KeyValuePair.New(hash, id));
}
}
public DhtRing(IActorId self)
{
this.HashAlgorithm = new SHA1Managed();
this.SelfId = self;
this.actors.Add(KeyValuePair.New(HashAlgorithm.ComputeHash(self.ToString()), self));
}
public IActorId Find(int ttl, IActorId originator = null)
{
lock (actors)
{
if (ttl < 0) return null;
int selfIndex = SelfIndex;
if (selfIndex < 0) return null;
int distance = (int)Math.Pow(2, ttl);
if (distance >= actors.Count) return null;
int endPoint = selfIndex + distance;
if (endPoint >= actors.Count)
endPoint -= actors.Count;
var destination = actors[endPoint];
if (destination.Equals(SelfId)) return null;
if (originator == null) originator = SelfId;
var hash = HashAlgorithm.ComputeHash(originator.ToString());
var originatorIndex = actors.BinarySearch(KeyValuePair.New(hash,(IActorId) null), n => n.Key);
if (IsBetween(originatorIndex, selfIndex, endPoint))
{
// if the originator is between us and the endpoint it means
// if we send this message it will have wrapped completely around
// the ring. if we do that nodes will receive the same message twice
// so stop this message instead.
return null;
}
return destination.Value;
}
}
