private void ConnectionReady_Handler(IAsyncResult ar)
{
lock (this)
{
if (_listener == null)
{
return;
}
Socket conn = _listener.EndAccept(ar);
if (_connections.Count >= _maxConnections)
{
//Max number of connections reached.
string msg = "SE001: Server busy";
conn.Send(Encoding.UTF8.GetBytes(msg), 0,
msg.Length, SocketFlags.None);
conn.Shutdown(SocketShutdown.Both);
conn.Close();
}
else
{
//Start servicing a new connection
tcpConnection st = new tcpConnection();
st._conn = conn;
st._server = this;
st._provider = (TcpServiceProvider)_provider.Clone();
st._buffer = new byte[4];
_connections.Add(st);
//Queue the rest of the job to be executed latter
ThreadPool.QueueUserWorkItem(AcceptConnection, st);
}
//Resume the listening callback loop
_listener.BeginAccept(ConnectionReady, null);
}
}
private void ReceivedDataReady_Handler(IAsyncResult ar)
{
tcpConnection st = ar.AsyncState as tcpConnection;
st._conn.EndReceive(ar);
//Im considering the following condition as a signal that the
//remote host droped the connection.
if (st._conn.Available == 0)
{
DropConnection(st);
}
else
{
try { st._provider.OnReceiveData(st); }
catch
{
//report error in the provider
}
//Resume ReceivedData callback loop
if (st._conn.Connected)
{
st._conn.BeginReceive(st._buffer, 0, 0, SocketFlags.None,
ReceivedDataReady, st);
}
}
}
internal void DropConnection(tcpConnection st)
{
lock (this)
{
st._conn.Shutdown(SocketShutdown.Both);
st._conn.Close();
if (_connections.Contains(st))
{
_connections.Remove(st);
}
}
}
private void AcceptConnection_Handler(object state)
{
tcpConnection st = state as tcpConnection;
try { st._provider.OnAcceptConnection(st); }
catch
{
//report error in provider... Probably to the EventLog
}
//Starts the ReceiveData callback loop
if (st._conn.Connected)
{
st._conn.BeginReceive(st._buffer, 0, 0, SocketFlags.None,
ReceivedDataReady, st);
}
}
public void Stop()
{
lock (this)
{
_listener.Close();
_listener = null;
//Close all active connections
foreach (object obj in _connections)
{
tcpConnection st = obj as tcpConnection;
try { st._provider.OnDropConnection(st); }
catch
{
//some error in the provider
}
st._conn.Shutdown(SocketShutdown.Both);
st._conn.Close();
}
_connections.Clear();
}
}
public abstract void OnDropConnection(tcpConnection state);
public abstract void OnReceiveData(tcpConnection state);
public abstract void OnAcceptConnection(tcpConnection state);
