public LibuvTransportFactory(
#pragma warning disable CS0618
IOptions <LibuvTransportOptions> options,
#pragma warning restore CS0618
IHostApplicationLifetime applicationLifetime,
ILoggerFactory loggerFactory)
{
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (applicationLifetime == null)
{
throw new ArgumentNullException(nameof(applicationLifetime));
}
if (loggerFactory == null)
{
throw new ArgumentNullException(nameof(loggerFactory));
}
var logger = loggerFactory.CreateLogger("Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv");
var trace = new LibuvTrace(logger);
#pragma warning disable CS0618
var threadCount = options.Value.ThreadCount;
#pragma warning restore CS0618
if (threadCount <= 0)
{
throw new ArgumentOutOfRangeException(nameof(threadCount),
threadCount,
"ThreadCount must be positive.");
}
if (!LibuvConstants.ECONNRESET.HasValue)
{
trace.LogWarning("Unable to determine ECONNRESET value on this platform.");
}
if (!LibuvConstants.EADDRINUSE.HasValue)
{
trace.LogWarning("Unable to determine EADDRINUSE value on this platform.");
}
_baseTransportContext = new LibuvTransportContext
{
Options = options.Value,
AppLifetime = applicationLifetime,
Log = trace,
};
}
private async Task ApplyBackpressureAsync(ValueTask <FlushResult> flushTask)
{
LibuvTrace.ConnectionPause(Log, ConnectionId);
_socket.ReadStop();
var result = await flushTask;
// If the reader isn't complete or cancelled then resume reading
if (!result.IsCompleted && !result.IsCanceled)
{
LibuvTrace.ConnectionResume(Log, ConnectionId);
StartReading();
}
}
private void OnRead(UvStreamHandle handle, int status)
{
// Cleanup state from last OnAlloc. This is safe even if OnAlloc wasn't called.
_bufferHandle.Dispose();
if (status == 0)
{
// EAGAIN/EWOULDBLOCK so just return the buffer.
// http://docs.libuv.org/en/v1.x/stream.html#c.uv_read_cb
}
else if (status > 0)
{
LibuvTrace.ConnectionRead(Log, ConnectionId, status);
Input.Advance(status);
var flushTask = Input.FlushAsync();
if (!flushTask.IsCompleted)
{
// We wrote too many bytes to the reader, so pause reading and resume when
// we hit the low water mark.
_ = ApplyBackpressureAsync(flushTask);
}
}
else
{
// Given a negative status, it's possible that OnAlloc wasn't called.
_socket.ReadStop();
Exception error = null;
if (status == LibuvConstants.EOF)
{
LibuvTrace.ConnectionReadFin(Log, ConnectionId);
}
else
{
handle.Libuv.Check(status, out var uvError);
error = LogAndWrapReadError(uvError);
}
FireConnectionClosed();
// Complete after aborting the connection
Input.Complete(error);
}
}
private Exception LogAndWrapReadError(UvException uvError)
{
if (uvError.StatusCode == LibuvConstants.ECANCELED)
{
// The operation was canceled by the server not the client. No need for additional logs.
return(new ConnectionAbortedException(uvError.Message, uvError));
}
else if (LibuvConstants.IsConnectionReset(uvError.StatusCode))
{
// Log connection resets at a lower (Debug) level.
LibuvTrace.ConnectionReset(Log, ConnectionId);
return(new ConnectionResetException(uvError.Message, uvError));
}
else
{
// This is unexpected.
LibuvTrace.ConnectionError(Log, ConnectionId, uvError);
return(new IOException(uvError.Message, uvError));
}
}
/// <summary>
/// Handles an incoming connection
/// </summary>
/// <param name="listenSocket">Socket being used to listen on</param>
/// <param name="status">Connection status</param>
private void OnConnection(UvStreamHandle listenSocket, int status)
{
UvStreamHandle acceptSocket = null;
try
{
acceptSocket = CreateAcceptSocket();
listenSocket.Accept(acceptSocket);
DispatchConnection(acceptSocket);
}
catch (UvException ex) when(LibuvConstants.IsConnectionReset(ex.StatusCode))
{
LibuvTrace.ConnectionReset(Log, "(null)");
acceptSocket?.Dispose();
}
catch (UvException ex)
{
Log.LogError(0, ex, "Listener.OnConnection");
acceptSocket?.Dispose();
}
}
private void ReadStartCallback(UvStreamHandle handle, int status)
{
if (status < 0)
{
if (status != LibuvConstants.EOF)
{
Thread.Loop.Libuv.Check(status, out var ex);
Log.LogError(0, ex, "DispatchPipe.ReadStart");
}
DispatchPipe.Dispose();
return;
}
if (_closed || DispatchPipe.PendingCount() == 0)
{
return;
}
var acceptSocket = CreateAcceptSocket();
try
{
DispatchPipe.Accept(acceptSocket);
HandleConnection(acceptSocket);
}
catch (UvException ex) when(LibuvConstants.IsConnectionReset(ex.StatusCode))
{
LibuvTrace.ConnectionReset(Log, "(null)");
acceptSocket.Dispose();
}
catch (UvException ex)
{
Log.LogError(0, ex, "DispatchPipe.Accept");
acceptSocket.Dispose();
}
}
private void LogWriteInfo(int status, Exception error)
{
if (error == null)
{
LibuvTrace.ConnectionWriteCallback(_log, _connectionId, status);
}
else
{
// Log connection resets at a lower (Debug) level.
if (status == LibuvConstants.ECANCELED)
{
// Connection was aborted.
}
else if (LibuvConstants.IsConnectionReset(status))
{
LibuvTrace.ConnectionReset(_log, _connectionId);
}
else
{
LibuvTrace.ConnectionError(_log, _connectionId, error);
}
}
}
protected internal void HandleConnection(UvStreamHandle socket)
{
try
{
IPEndPoint remoteEndPoint = null;
IPEndPoint localEndPoint = null;
if (socket is UvTcpHandle tcpHandle)
{
try
{
remoteEndPoint = tcpHandle.GetPeerIPEndPoint();
localEndPoint = tcpHandle.GetSockIPEndPoint();
}
catch (UvException ex) when(LibuvConstants.IsConnectionReset(ex.StatusCode))
{
LibuvTrace.ConnectionReset(TransportContext.Log, "(null)");
socket.Dispose();
return;
}
}
var options = TransportContext.Options;
#pragma warning disable CS0618
var connection = new LibuvConnection(socket, TransportContext.Log, Thread, remoteEndPoint, localEndPoint, InputOptions, OutputOptions, options.MaxReadBufferSize, options.MaxWriteBufferSize);
#pragma warning restore CS0618
connection.Start();
bool accepted = _acceptQueue.Writer.TryWrite(connection);
Debug.Assert(accepted, "The connection was not written to the channel!");
}
catch (Exception ex)
{
TransportContext.Log.LogCritical(ex, $"Unexpected exception in {nameof(ListenerContext)}.{nameof(HandleConnection)}.");
}
}
private async Task StartCore()
{
try
{
OutputConsumer = new LibuvOutputConsumer(Output, Thread, _socket, ConnectionId, Log);
StartReading();
Exception inputError = null;
Exception outputError = null;
try
{
// This *must* happen after socket.ReadStart
// The socket output consumer is the only thing that can close the connection. If the
// output pipe is already closed by the time we start then it's fine since, it'll close gracefully afterwards.
await OutputConsumer.WriteOutputAsync();
}
catch (UvException ex)
{
// The connection reset/error has already been logged by LibuvOutputConsumer
if (ex.StatusCode == LibuvConstants.ECANCELED)
{
// Connection was aborted.
}
else if (LibuvConstants.IsConnectionReset(ex.StatusCode))
{
// Don't cause writes to throw for connection resets.
inputError = new ConnectionResetException(ex.Message, ex);
}
else
{
// This is unexpected.
LibuvTrace.ConnectionError(Log, ConnectionId, ex);
inputError = ex;
outputError = ex;
}
}
finally
{
inputError ??= _abortReason ?? new ConnectionAbortedException("The libuv transport's send loop completed gracefully.");
// Now, complete the input so that no more reads can happen
Input.Complete(inputError);
Output.Complete(outputError);
// Make sure it isn't possible for a paused read to resume reading after calling uv_close
// on the stream handle
Input.CancelPendingFlush();
// Send a FIN
LibuvTrace.ConnectionWriteFin(Log, ConnectionId, inputError.Message);
// We're done with the socket now
_socket.Dispose();
// Ensure this always fires
FireConnectionClosed();
await _waitForConnectionClosedTcs.Task;
}
}
catch (Exception e)
{
Log.LogCritical(0, e, $"{nameof(LibuvConnection)}.{nameof(Start)}() {ConnectionId}");
}
}