/// <summary>
/// Called by a session to remove itself when it's no longer needed
/// </summary>
/// <param name="tftpSession">The session to remove</param>
internal void UnregisterSession(TftpSession tftpSession)
{
if (!Sessions.TryRemove(tftpSession.RemoteHost, out TftpSession removedSession))
{
throw new Exception("Could not remove session " + tftpSession.RemoteHost.ToString() + " from known sessions");
}
}
/// <summary>
/// Handle the incoming UDP packet
/// </summary>
public void OnUdpData(IPEndPoint source, byte[] messageData)
{
try
{
if (!Sessions.TryGetValue(source, out TftpSession session))
{
LogDebug($"New client detected from {source.Address}:{source.Port}");
session = new TftpSession(this, source);
Sessions[source] = session;
}
Task.Factory.StartNew(
async() => {
try
{
await session.OnReceiveAsync(messageData);
}
catch (Exception e)
{
LogError("Internal error: " + e.Message);
}
}
);
}
catch (Exception e)
{
LogError("Internal error: " + e.Message);
}
}
private void EmitSessionError(TftpSession session, string reason)
{
EventHandler <TftpTransferErrorEventArgs> handler =
(session.Operation == ETftpOperationType.WriteOperation) ?
FileReceiveError :
FileTransmitError
;
var eventArgs = new TftpTransferErrorEventArgs
{
Id = session.Id,
Operation = session.Operation,
Filename = session.Filename,
RemoteHost = session.RemoteHost,
Stream = (session.Operation == ETftpOperationType.WriteOperation) ? (MemoryStream)session.TransferStream : null,
TransferInitiated = session.TransferRequestInitiated,
TransferCompleted = DateTimeOffset.Now,
Transferred = session.Position,
FailureReason = reason
};
handler?.Invoke(
this,
eventArgs
);
var invocationList =
(session.Operation == ETftpOperationType.WriteOperation) ?
(FileReceiveErrorAsync?.GetInvocationList()) :
(FileTransmitErrorAsync?.GetInvocationList())
;
if (invocationList == null)
{
return;
}
var handlerTasks = new Task[invocationList.Length];
for (int i = 0; i < invocationList.Length; i++)
{
handlerTasks[i] = ((Func <object, TftpTransferErrorEventArgs, Task>)invocationList[i])(this, eventArgs);
}
Task.WhenAll(handlerTasks);
}
private void OnUdpData(IAsyncResult result)
{
var timeReceived = DateTimeOffset.Now;
var socket = result.AsyncState as UdpClient;
try
{
IPEndPoint source = new IPEndPoint(0, 0);
var messageData = socket.EndReceive(result, ref source);
if (!Sessions.TryGetValue(source, out TftpSession session))
{
LogDebug($"New client detected from {source.Address}:{source.Port}");
session = new TftpSession(this, source);
Sessions[source] = session;
}
var receiveTask =
Task.Factory.StartNew(
async() => {
try
{
await session.OnReceiveAsync(messageData);
}
catch (Exception e)
{
LogError("Internal error: " + e.Message);
}
}
);
}
catch (Exception e)
{
LogError("Internal error: " + e.Message);
}
socket.BeginReceive(new AsyncCallback(OnUdpData), socket);
}
/// <summary>
/// Called by a session to signal that it's complete
/// </summary>
/// <param name="session">The transfer which is complete</param>
internal async Task TransferCompleteAsync(TftpSession session)
{
UnregisterSession(session);
EventHandler <TftpTransferCompleteEventArgs> handler =
(session.Operation == ETftpOperationType.WriteOperation) ?
FileReceived :
FileTransmitted
;
var eventArgs = new TftpTransferCompleteEventArgs
{
Id = session.Id,
Operation = session.Operation,
Filename = session.Filename,
RemoteHost = session.RemoteHost,
Stream = (session.Operation == ETftpOperationType.WriteOperation) ? (MemoryStream)session.TransferStream : null,
TransferInitiated = session.TransferRequestInitiated,
TransferCompleted = DateTimeOffset.Now,
Transferred = session.Position
};
handler?.Invoke(
this,
eventArgs
);
var invocationList =
(session.Operation == ETftpOperationType.WriteOperation) ?
(FileReceivedAsync?.GetInvocationList()) :
(FileTransmittedAsync?.GetInvocationList())
;
if (invocationList == null)
{
return;
}
var handlerTasks = new Task[invocationList.Length];
for (int i = 0; i < invocationList.Length; i++)
{
handlerTasks[i] =
((Func <object, TftpTransferCompleteEventArgs, Task>)invocationList[i])(
this,
new TftpTransferCompleteEventArgs
{
Id = session.Id,
Operation = session.Operation,
Filename = session.Filename,
RemoteHost = session.RemoteHost,
Stream = (session.Operation == ETftpOperationType.WriteOperation) ? (MemoryStream)session.TransferStream : null,
TransferInitiated = session.TransferRequestInitiated,
TransferCompleted = DateTimeOffset.Now,
Transferred = session.Position
}
);
}
await Task.WhenAll(handlerTasks);
}
