/// <summary>
/// Registers a new local peer. The calling function has to pass
/// in a Code that is a unique name for the peer. No other peer
/// by this name can exist locally. Returns null if it already
/// exists, or a new NodePeer object if successful.
/// </summary>
/// <param name="Code">Unique name for the new peer</param>
/// <returns></returns>
public static NodePeer RegisterLocalPeer(FieldIdentifier Code)
{
if (Code == null)
{
throw new ArgumentNullException("Code");
}
lock (Instance.m_localPeerList_Lock)
{
//make sure "Local.{thisCode}" doesn't exist yet
//(no duplicate peer names)
bool found = false;
foreach (NodePeer p in Instance.m_localPeerList.Peers)
{
if (p.Code == Code)
{
found = true;
break;
}
}
if (found)
{
return(null);
}
else
{
NodePeer newPeer = NodePeer.BuildWith(Code);
LocalPeerList = LocalPeerList.Peers.Append(newPeer);
return(newPeer);
}
}
}
/// <summary>
/// Unregisters a peer that was created by calling the
/// RegisterLocalPeer function. Throws an exception if
/// the peer is not a local peer.
/// </summary>
/// <param name="Peer"></param>
/// <returns>True if successful, False otherwise</returns>
public static bool UnregisterLocalPeer(NodePeer Peer)
{
if (Peer == null)
{
throw new ArgumentNullException("Peer");
}
if (!Peer.IsLocal)
{
throw new ArgumentOutOfRangeException("Peer");
}
lock (Instance.m_localPeerList_Lock)
{
if (Instance.m_localPeerList.Peers.Contains(Peer))
{
Peer.Unregister(); //clears all event handlers
LocalPeerList = LocalPeerList.Peers.Remove(Peer);
return(true);
}
else
{
return(false);
}
}
}
/// <summary>
/// When the local peer list changes, we have to send updates to
/// the other end of this connection.
/// </summary>
/// <param name="newPeerList"></param>
/// <param name="oldPeerList"></param>
private void LocalPeerListChangedCallback(NodePeerList newPeerList,
NodePeerList oldPeerList)
{
string s = newPeerList.ToXml(oldPeerList);
Send(s);
}
public static NodePeerList BuildWith(ReadOnlyCollection <NodePeer> Peers)
{
//build node
NodePeerList Builder = BuildWith();
//add the peer list
Builder = Builder.Peers.Append(Peers);
return(Builder);
}
public static NodePeerList BuildWith()
{
//build fields
Dictionary <FieldIdentifier, FieldBase> mutableFields =
new Dictionary <FieldIdentifier, FieldBase>();
//build children
KeyedNodeCollection <NodeBase> mutableChildren =
new KeyedNodeCollection <NodeBase>();
//build node
NodePeerList Builder = new NodePeerList(
new ReadOnlyDictionary <FieldIdentifier, FieldBase>(mutableFields),
new ReadOnlyCollection <NodeBase>(mutableChildren));
return(Builder);
}
internal void ThreadStart(Object o)
{
SslStream sslStream = o as SslStream;
if (sslStream != null)
{
//Have to send the local peer list to the other end of
//the connection, and we also need to be notified of any
//changes to the local peer list. This has to be done
//in one operation so a new node can't sneak in between
//us reading the nodelist, and us registering the event.
lock (m_OutgoingQueue_Lock) //don't let the callback enqueue a message first
{
NodePeerList localPeerList =
CommunicationManager.RegisterLocalPeerListChangedCallback(
new CommunicationManager.LocalPeerListChangedHandler(
LocalPeerListChangedCallback));
Send(localPeerList.ToXml());
}
//kick off a read callback chain of threads
lock (m_ReadCallback_Lock)
{
sslStream.BeginRead(m_newData, 0, m_newData.Length,
new AsyncCallback(ReadCallback), sslStream);
}
bool stop = false;
while (!stop)
{
//send any queued messages
int outgoingCount = 0;
lock (m_OutgoingQueue_Lock)
{
outgoingCount = m_OutgoingQueue.Count;
}
while (outgoingCount > 0)
{
string data = null;
lock (m_OutgoingQueue_Lock)
{
data = m_OutgoingQueue.Dequeue();
}
//encode it to base 64 so we don't have to worry about control codes
byte[] encbuf = System.Text.Encoding.Unicode.GetBytes(data);
string encodedData = Convert.ToBase64String(encbuf) + "\n"; //terminate in newline to denote the end of the message
//convert to a byte array
byte[] writebuf = System.Text.Encoding.ASCII.GetBytes(encodedData);
sslStream.Write(writebuf);
sslStream.Flush();
outgoingCount--;
}
//process any received messages
int incomingCount = 0;
lock (m_IncomingQueue_Lock)
{
incomingCount = m_IncomingQueue.Count;
}
while (incomingCount > 0)
{
string data = null;
lock (m_IncomingQueue_Lock)
{
data = m_IncomingQueue.Dequeue();
}
//message is in base 64, so convert back to a string
byte[] decbuff = Convert.FromBase64String(data);
string message = System.Text.Encoding.Unicode.GetString(decbuff);
Receive(message);
incomingCount--;
}
//wait
System.Threading.Thread.Sleep(100);
lock (m_CloseRequest_Lock)
{
if (stop == false)
{
stop = m_CloseRequest;
}
}
}
//See if we closed due to an exception in the reader thread
Exception readException = null;
lock (m_readException_Lock)
{
readException = m_readException;
}
if (readException != null)
{
//TODO propagate this exception to higher code
}
//clean up the stream
sslStream.Close();
}
}
private void Receive(string message)
{
//TextWriter tw = new StreamWriter("receive_" + this.ID.ToString() + ".txt", true);
//tw.WriteLine(message);
//tw.Close();
if (ValidateXmlToSchema(message))
{
FieldGuid toPeerID = NodeBase.ToPeerFromXML(message);
FieldGuid fromPeerID = NodeBase.FromPeerFromXML(message);
if (toPeerID != null && fromPeerID != null)
{
//it's a peer-to-peer message
//find the ToPeer in the local peer list
NodePeer ToPeer = CommunicationManager.LocalPeerList.FindPeerByID(toPeerID);
//find the FromPeer in the remote peer list
NodePeer FromPeer = RemotePeerList.FindPeerByID(fromPeerID);
if (ToPeer != null && FromPeer != null)
{
//see if this message is based on another node
FieldGuid BasedOnNodeID = NodeBase.BasedOnNodeIDFromXML(message);
NodeBase basedOnNode = null;
if (BasedOnNodeID != null)
{
basedOnNode = ToPeer.ReceiveDeltaFromPeer(FromPeer, BasedOnNodeID);
NodeBase msg = NodeBase.NodeFromXML(message, basedOnNode.GetChildrenRecursive());
CommunicationManager.SendDeltaToPeer(ToPeer, FromPeer, msg, basedOnNode);
}
else
{
NodeBase msg = NodeBase.NodeFromXML(message, null);
CommunicationManager.SendToPeer(ToPeer, FromPeer, msg);
}
}
else
{
//TODO - log this - undeliverable message (peer lists not up to date?)
}
}
else
{
//it's a system message (not peer-to-peer)
FieldNodeType nodeType = NodeBase.NodeTypeFromXML(message);
if (nodeType.ToString() == typeof(NodePeerList).FullName)
{
lock (m_remotePeerList_Lock) //lock so we read/write in one operation
{
//When we receive a remote peer list, it is generally just a diff
//from the last peer list.
RemotePeerList = (NodePeerList)NodeBase.NodeFromXML(
message, RemotePeerList.GetChildrenRecursive());
}
}
else
{
//TODO - log this? Unknown root message type?
}
}
}
else
{
//TODO - log this? Unknown garbage message?
}
}
