internal bool Ping(NodeContact contact)
{
DhtRpcPacket response = Query(DhtRpcPacket.CreatePingPacketQuery(_currentNode), contact);
if (response == null)
{
return(false);
}
else
{
if (contact.Equals(response.SourceNode))
{
return(true);
}
else
{
contact.IncrementRpcFailCount();
return(false);
}
}
}
public bool AddContact(NodeContact contact)
{
KBucket currentBucket = this;
while (true)
{
NodeContact[] contacts = currentBucket._contacts;
KBucket leftBucket = currentBucket._leftBucket;
KBucket rightBucket = currentBucket._rightBucket;
lock (currentBucket)
{
if ((contacts != null) || (leftBucket == null) || (rightBucket == null))
{
#region add contact in this bucket
//search if contact already exists
for (int i = 0; i < contacts.Length; i++)
{
if (contact.Equals(contacts[i]))
{
return(false); //contact already exists
}
}
//try add contact
for (int i = 0; i < contacts.Length; i++)
{
if (contacts[i] == null)
{
contacts[i] = contact;
currentBucket._contactCount++;
currentBucket._lastChanged = DateTime.UtcNow;
return(true);
}
}
//k-bucket is full so contact was not added
//if current contact is not stale then find and replace with any existing stale contact
if (!contact.IsStale())
{
for (int i = 0; i < contacts.Length; i++)
{
if (contacts[i].IsStale())
{
contacts[i] = contact;
currentBucket._lastChanged = DateTime.UtcNow;
return(true);
}
}
}
//no stale contact in this k-bucket to replace!
if (contacts[0].IsCurrentNode)
{
//split current bucket and add contact!
SplitBucket(currentBucket, contact);
return(true);
}
else
{
//k-bucket is full!
return(false);
}
#endregion
}
}
if ((leftBucket._bucketID & contact.NodeID) == leftBucket._bucketID)
{
currentBucket = leftBucket;
}
else
{
currentBucket = rightBucket;
}
}
}
public bool RemoveContact(NodeContact contact)
{
KBucket currentBucket = this;
while (true)
{
NodeContact[] contacts = currentBucket._contacts;
KBucket leftBucket = currentBucket._leftBucket;
KBucket rightBucket = currentBucket._rightBucket;
lock (currentBucket)
{
if ((contacts != null) || (leftBucket == null) || (rightBucket == null))
{
#region remove contact from this bucket
if (currentBucket._contactCount <= DhtNode.KADEMLIA_K)
{
return(false); //k-bucket is not full and replacement cache is empty
}
bool contactRemoved = false;
for (int i = 0; i < contacts.Length; i++)
{
if (contact.Equals(contacts[i]))
{
if (contacts[i].IsStale())
{
//remove stale contact
contacts[i] = null;
currentBucket._contactCount--;
currentBucket._lastChanged = DateTime.UtcNow;
contactRemoved = true;
}
break;
}
}
if (!contactRemoved)
{
return(false); //contact was not found or was not stale
}
//check parent bucket contact count and join the parent bucket
if (currentBucket._parentBucket != null)
{
JoinBucket(currentBucket._parentBucket);
}
return(true);
#endregion
}
}
if ((leftBucket._bucketID & contact.NodeID) == leftBucket._bucketID)
{
currentBucket = leftBucket;
}
else
{
currentBucket = rightBucket;
}
}
}
public bool RemoveContact(NodeContact contact)
{
KBucket currentBucket = this;
while (true)
{
NodeContact[] contacts;
KBucket leftBucket;
KBucket rightBucket;
lock (currentBucket)
{
contacts = currentBucket._contacts;
leftBucket = currentBucket._leftBucket;
rightBucket = currentBucket._rightBucket;
if (contacts != null)
{
#region remove contact from this bucket
if (currentBucket._contactCount <= DhtNode.KADEMLIA_K)
{
return(false); //k-bucket is not full and replacement cache is empty
}
for (int i = 0; i < contacts.Length; i++)
{
if (contact.Equals(contacts[i]))
{
if (contacts[i].IsStale())
{
//remove stale contact
contacts[i] = null;
currentBucket._lastChanged = DateTime.UtcNow;
KBucket bucket = currentBucket;
do
{
Interlocked.Decrement(ref bucket._contactCount);
bucket = bucket._parentBucket;
}while (bucket != null);
return(true);
}
break;
}
}
return(false); //contact was not found or was not stale
#endregion
}
}
if ((leftBucket._bucketID & contact.NodeID) == leftBucket._bucketID)
{
currentBucket = leftBucket;
}
else
{
currentBucket = rightBucket;
}
}
}