public PeerId[] NearestPeers(DhtId id, int count)
{
var cpl = DhtId.CommonPrefixLength(id, _local);
lock (_tabLock)
{
if (cpl >= Buckets.Length)
{
cpl = Buckets.Length - 1;
}
var bucket = Buckets[cpl];
var peers = Util.CopyPeersFromList(id, bucket.Peers);
if (peers.Count() < count)
{
if (cpl > 0)
{
var plist = Buckets[cpl - 1].Peers;
peers = Util.CopyPeersFromList(id, plist);
}
if (cpl < Buckets.Length - 1)
{
var plist = Buckets[cpl + 1].Peers;
peers = Util.CopyPeersFromList(id, plist);
}
}
return(peers.OrderBy(p => p.Distance, new Util.DistanceComparer())
.Take(count)
.Select(p => p.P).ToArray());
}
}
public Bucket Split(int cpl, DhtId target)
{
_rwlock.EnterWriteLock();
try
{
var output = new List <PeerId>();
var newBuck = new Bucket(output);
foreach (var e in _list)
{
var peerId = DhtId.ConvertPeerId(e);
var peerCpl = DhtId.CommonPrefixLength(peerId, target);
if (peerCpl > cpl)
{
output.Add(e);
}
}
_list.RemoveAll(output.Contains);
return(newBuck);
}
finally
{
_rwlock.ExitWriteLock();
}
}
public RoutingTable(int bucketSize, DhtId localId, TimeSpan latency, IMetrics metrics)
{
Buckets = new[] { new Bucket() };
_bucketSize = bucketSize;
_local = localId;
_maxLatency = latency;
_metrics = metrics;
_tabLock = new object();
}
public PeerId NearestPeer(DhtId id)
{
var peers = NearestPeers(id, 1);
if (peers.Length > 0)
{
return(peers[0]);
}
return(null);
}
public PeerId Find(PeerId id)
{
var srch = NearestPeers(DhtId.ConvertPeerId(id), 1);
if (srch.Length == 0 || srch[0] != id)
{
return(null);
}
return(srch[0]);
}
public void Remove(PeerId p)
{
lock (_tabLock)
{
var peerId = DhtId.ConvertPeerId(p);
var cpl = DhtId.CommonPrefixLength(peerId, _local);
var bucketId = cpl;
if (bucketId >= Buckets.Length)
{
bucketId = Buckets.Length - 1;
}
var bucket = Buckets[bucketId];
bucket.Remove(p);
}
}
public void Update(PeerId p)
{
var peerId = DhtId.ConvertPeerId(p);
var cpl = DhtId.CommonPrefixLength(peerId, _local);
lock (_tabLock)
{
var bucketId = cpl;
if (bucketId >= Buckets.Length)
{
bucketId = Buckets.Length - 1;
}
var bucket = Buckets[bucketId];
if (bucket.Has(p))
{
bucket.MoveToFront(p);
return;
}
if (_metrics.LatencyEWMA(p) > _maxLatency)
{
return;
}
bucket.PushFront(p);
if (bucket.Length > _bucketSize)
{
if (bucketId == Buckets.Length - 1)
{
NextBucket();
}
else
{
bucket.PopBack();
}
}
}
}
public static IEnumerable <PeerId> SortClosestPeers(IEnumerable <PeerId> peers, DhtId target)
{
return(CopyPeersFromList(target, peers)
.OrderBy(p => p.Distance, new DistanceComparer())
.Select(p => p.P));
}
public static IEnumerable <PeerDistance> CopyPeersFromList(DhtId target, IEnumerable <PeerId> peers)
{
return(from peer in peers let pid = DhtId.ConvertPeerId(peer) select new PeerDistance {
P = peer, Distance = ((byte[])target).XOR(pid)
});
}
