/// <summary>
/// Open a new or existing socket as a client
/// </summary>
public static async Task <SocketConnection> ConnectAsync(
EndPoint endpoint,
PipeOptions sendPipeOptions,
PipeOptions receivePipeOptions,
SocketConnectionOptions connectionOptions = SocketConnectionOptions.None,
Func <SocketConnection, Task> onConnected = null,
Socket socket = null,
string name = null,
ILogger logger = null)
{
var addressFamily = endpoint.AddressFamily == AddressFamily.Unspecified ?
AddressFamily.InterNetwork : endpoint.AddressFamily;
var protocolType = addressFamily == AddressFamily.Unix ?
ProtocolType.Unspecified : ProtocolType.Tcp;
if (socket == null)
{
socket = new Socket(addressFamily, SocketType.Stream, protocolType);
}
if (sendPipeOptions == null)
{
sendPipeOptions = PipeOptions.Default;
}
if (receivePipeOptions == null)
{
receivePipeOptions = PipeOptions.Default;
}
SetRecommendedClientOptions(socket);
logger = logger ?? NullLoggerFactory.Instance.CreateLogger("NetGear.Core.SocketConnection");
using (var args = new SocketAwaitableEventArgs((connectionOptions & SocketConnectionOptions.InlineConnect) == 0 ? PipeScheduler.ThreadPool : null))
{
args.RemoteEndPoint = endpoint;
_logger.LogVerbose(name, $"connecting to {endpoint}...");
if (!socket.ConnectAsync(args))
{
args.Complete();
}
await args;
}
_logger.LogVerbose(name, "connected");
var connection = Create(socket, sendPipeOptions, receivePipeOptions, connectionOptions, name, logger);
if (onConnected != null)
{
await onConnected(connection).ConfigureAwait(false);
}
return(connection);
}
private async Task DoReceiveAsync()
{
Exception error = null;
DebugLog("starting receive loop");
try
{
// 说明：recv方向上是recv from socket and push to pipe，所以这里回调应该是
// 执行在WriterScheduler上
_readerArgs = new SocketAwaitableEventArgs(InlineReads ? null : _receiveOptions.WriterScheduler);
while (true)
{
if (ZeroLengthReads && Socket.Available == 0)
{
DebugLog($"awaiting zero-length receive...");
CounterHelper.Incr(Counter.OpenReceiveReadAsync);
DoReceive(Socket, _readerArgs, default, Name);
private async Task DoSendAsync()
{
Exception error = null;
DebugLog("starting send loop");
try
{
while (true)
{
DebugLog("awaiting data from pipe...");
if (_sendToSocket.Reader.TryRead(out var result))
{
CounterHelper.Incr(Counter.SocketPipeReadReadSync);
}
else
{
CounterHelper.Incr(Counter.OpenSendReadAsync);
var read = _sendToSocket.Reader.ReadAsync();
CounterHelper.Incr(read.IsCompleted ? Counter.SocketPipeReadReadSync : Counter.SocketPipeReadReadAsync);
result = await read;
CounterHelper.Decr(Counter.OpenSendReadAsync);
}
var buffer = result.Buffer;
if (result.IsCanceled || (result.IsCompleted && buffer.IsEmpty))
{
DebugLog(result.IsCanceled ? "cancelled" : "complete");
break;
}
try
{
if (!buffer.IsEmpty)
{
// 说明：send方向上是read from pipe and send to socket，所以这里回调应该是
// 执行在ReaderScheduler上
if (_writerArgs == null)
{
_writerArgs = new SocketAwaitableEventArgs(InlineWrites ? null : _sendOptions.ReaderScheduler);
}
DebugLog($"sending {buffer.Length} bytes over socket...");
CounterHelper.Incr(Counter.OpenSendWriteAsync);
DoSend(Socket, _writerArgs, buffer, Name);
CounterHelper.Incr(_writerArgs.IsCompleted ? Counter.SocketSendAsyncSync : Counter.SocketSendAsyncAsync);
DebugLog(_writerArgs.IsCompleted ? "send is sync" : "send is async");
var bytesSend = await _writerArgs;
Interlocked.Add(ref _totalBytesSent, bytesSend);
CounterHelper.Decr(Counter.OpenSendWriteAsync);
}
else if (result.IsCompleted)
{
DebugLog("completed");
break;
}
}
finally
{
DebugLog("advancing");
_sendToSocket.Reader.AdvanceTo(buffer.End);
}
}
TrySetShutdown(PipeShutdownKind.WriteEndOfStream);
}
catch (SocketException ex) when(IsConnectionResetError(ex.SocketErrorCode))
{
TrySetShutdown(PipeShutdownKind.WriteSocketError, ex.SocketErrorCode);
DebugLog($"fail: {ex.SocketErrorCode}");
error = new ConnectionResetException(ex.Message, ex);
}
catch (SocketException ex) when(IsConnectionAbortError(ex.SocketErrorCode))
{
TrySetShutdown(PipeShutdownKind.WriteSocketError, ex.SocketErrorCode);
DebugLog($"fail: {ex.SocketErrorCode}");
// This should always be ignored since Shutdown() must have already been called by Abort().
error = ex;
}
catch (ObjectDisposedException ex)
{
TrySetShutdown(PipeShutdownKind.WriteDisposed);
DebugLog("fail: disposed");
error = ex;
}
catch (IOException ex)
{
TrySetShutdown(PipeShutdownKind.WriteIOException);
DebugLog($"fail - io: {ex.Message}");
error = ex;
}
catch (Exception ex)
{
TrySetShutdown(PipeShutdownKind.WriteException);
DebugLog($"fail: {ex.Message}");
error = ex;
}
finally
{
Shutdown(error);
error = error ?? _shutdownReason;
// close *both halves* of the send pipe; we're not
// listening *and* we don't want anyone trying to write
DebugLog($"marking {nameof(Output)} as complete");
try { _sendToSocket.Writer.Complete(error); } catch { }
try { _sendToSocket.Reader.Complete(error); } catch { }
TrySetShutdown(error, PipeShutdownKind.OutputReaderCompleted);
var args = _writerArgs;
_writerArgs = null;
if (args != null)
{
try { args.Dispose(); } catch { }
}
}
DebugLog(error == null ? "exiting with success" : $"exiting with failure: {error.Message}");
}
private void DoSend(Socket socket, SocketAwaitableEventArgs args, in ReadOnlySequence <byte> buffer, string name)