private static Exception CreateWrappedException(Exception error, CancellationToken cancellationToken)
{
return(CancellationHelper.ShouldWrapInOperationCanceledException(error, cancellationToken) ?
CancellationHelper.CreateOperationCanceledException(error, cancellationToken) :
new HttpRequestException(error.Message, error, RequestRetryType.RetryOnNextProxy));
}
private async ValueTask <int> ReadAsyncCore(Memory <byte> buffer, CancellationToken cancellationToken)
{
// Should only be called if ReadChunksFromConnectionBuffer returned 0.
Debug.Assert(_connection != null);
Debug.Assert(buffer.Length > 0);
CancellationTokenRegistration ctr = _connection.RegisterCancellation(cancellationToken);
try
{
while (true)
{
if (_connection == null)
{
// Fully consumed the response in ReadChunksFromConnectionBuffer.
return(0);
}
if (_state == ParsingState.ExpectChunkData &&
buffer.Length >= _connection.ReadBufferSize &&
_chunkBytesRemaining >= (ulong)_connection.ReadBufferSize)
{
// As an optimization, we skip going through the connection's read buffer if both
// the remaining chunk data and the buffer are both at least as large
// as the connection buffer. That avoids an unnecessary copy while still reading
// the maximum amount we'd otherwise read at a time.
Debug.Assert(_connection.RemainingBuffer.Length == 0);
int bytesRead = await _connection.ReadAsync(buffer.Slice(0, (int)Math.Min((ulong)buffer.Length, _chunkBytesRemaining))).ConfigureAwait(false);
if (bytesRead == 0)
{
throw new IOException(SR.Format(SR.net_http_invalid_response_premature_eof_bytecount, _chunkBytesRemaining));
}
_chunkBytesRemaining -= (ulong)bytesRead;
if (_chunkBytesRemaining == 0)
{
_state = ParsingState.ExpectChunkTerminator;
}
return(bytesRead);
}
// We're only here if we need more data to make forward progress.
await _connection.FillAsync().ConfigureAwait(false);
// Now that we have more, see if we can get any response data, and if
// we can we're done.
int bytesCopied = ReadChunksFromConnectionBuffer(buffer.Span, ctr);
if (bytesCopied > 0)
{
return(bytesCopied);
}
}
}
catch (Exception exc) when(CancellationHelper.ShouldWrapInOperationCanceledException(exc, cancellationToken))
{
throw CancellationHelper.CreateOperationCanceledException(exc, cancellationToken);
}
finally
{
ctr.Dispose();
}
}
public override async ValueTask <int> ReadAsync(Memory <byte> buffer, CancellationToken cancellationToken)
{
CancellationHelper.ThrowIfCancellationRequested(cancellationToken);
if (_connection == null || buffer.Length == 0)
{
// Response body fully consumed or the caller didn't ask for any data
return(0);
}
Debug.Assert(_contentBytesRemaining > 0);
if ((ulong)buffer.Length > _contentBytesRemaining)
{
buffer = buffer.Slice(0, (int)_contentBytesRemaining);
}
ValueTask <int> readTask = _connection.ReadAsync(buffer);
int bytesRead;
if (readTask.IsCompletedSuccessfully)
{
bytesRead = readTask.Result;
}
else
{
CancellationTokenRegistration ctr = _connection.RegisterCancellation(cancellationToken);
try
{
bytesRead = await readTask.ConfigureAwait(false);
}
catch (Exception exc) when(CancellationHelper.ShouldWrapInOperationCanceledException(exc, cancellationToken))
{
throw CancellationHelper.CreateOperationCanceledException(exc, cancellationToken);
}
finally
{
ctr.Dispose();
}
}
if (bytesRead <= 0)
{
// A cancellation request may have caused the EOF.
CancellationHelper.ThrowIfCancellationRequested(cancellationToken);
// Unexpected end of response stream.
throw new IOException(SR.Format(SR.net_http_invalid_response_premature_eof_bytecount, _contentBytesRemaining));
}
Debug.Assert((ulong)bytesRead <= _contentBytesRemaining);
_contentBytesRemaining -= (ulong)bytesRead;
if (_contentBytesRemaining == 0)
{
// End of response body
_connection.CompleteResponse();
_connection = null;
}
return(bytesRead);
}
protected override void OnCompleted(SocketAsyncEventArgs _)
{
switch (SocketError)
{
case SocketError.Success:
Builder.SetResult();
break;
case SocketError.OperationAborted:
case SocketError.ConnectionAborted:
if (CancellationToken.IsCancellationRequested)
{
Builder.SetException(ExceptionDispatchInfo.SetCurrentStackTrace(CancellationHelper.CreateOperationCanceledException(null, CancellationToken)));
break;
}
goto default;
default:
Builder.SetException(ExceptionDispatchInfo.SetCurrentStackTrace(new SocketException((int)SocketError)));
break;
}
}
private static Exception CreateWrappedException(Exception error, string host, int port, CancellationToken cancellationToken)
{
return(CancellationHelper.ShouldWrapInOperationCanceledException(error, cancellationToken) ?
CancellationHelper.CreateOperationCanceledException(error, cancellationToken) :
new HttpRequestException($"{error.Message} ({host}:{port})", error, RequestRetryType.RetryOnNextProxy));
}
private async ValueTask <int> ReadAsyncCore(Memory <byte> buffer, CancellationToken cancellationToken)
{
// Should only be called if ReadChunksFromConnectionBuffer returned 0.
Debug.Assert(_connection != null);
CancellationTokenRegistration ctr = _connection.RegisterCancellation(cancellationToken);
try
{
while (true)
{
if (_connection == null)
{
// Fully consumed the response in ReadChunksFromConnectionBuffer.
return(0);
}
if (_state == ParsingState.ExpectChunkData &&
buffer.Length >= _connection.ReadBufferSize &&
_chunkBytesRemaining >= (ulong)_connection.ReadBufferSize)
{
// As an optimization, we skip going through the connection's read buffer if both
// the remaining chunk data and the buffer are both at least as large
// as the connection buffer. That avoids an unnecessary copy while still reading
// the maximum amount we'd otherwise read at a time.
Debug.Assert(_connection.RemainingBuffer.Length == 0);
Debug.Assert(buffer.Length != 0);
int bytesRead = await _connection.ReadAsync(buffer.Slice(0, (int)Math.Min((ulong)buffer.Length, _chunkBytesRemaining))).ConfigureAwait(false);
if (bytesRead == 0)
{
throw new IOException(SR.Format(SR.net_http_invalid_response_premature_eof_bytecount, _chunkBytesRemaining));
}
_chunkBytesRemaining -= (ulong)bytesRead;
if (_chunkBytesRemaining == 0)
{
_state = ParsingState.ExpectChunkTerminator;
}
return(bytesRead);
}
if (buffer.Length == 0)
{
// User requested a zero-byte read, and we have no data available in the buffer for processing.
// This zero-byte read indicates their desire to trade off the extra cost of a zero-byte read
// for reduced memory consumption when data is not immediately available.
// So, we will issue our own zero-byte read against the underlying stream to allow it to make use of
// optimizations, such as deferring buffer allocation until data is actually available.
await _connection.ReadAsync(buffer).ConfigureAwait(false);
}
// We're only here if we need more data to make forward progress.
await _connection.FillAsync(async : true).ConfigureAwait(false);
// Now that we have more, see if we can get any response data, and if
// we can we're done.
if (buffer.Length == 0)
{
if (PeekChunkFromConnectionBuffer())
{
return(0);
}
}
else
{
int bytesCopied = ReadChunksFromConnectionBuffer(buffer.Span, ctr);
if (bytesCopied > 0)
{
return(bytesCopied);
}
}
}
}
catch (Exception exc) when(CancellationHelper.ShouldWrapInOperationCanceledException(exc, cancellationToken))
{
throw CancellationHelper.CreateOperationCanceledException(exc, cancellationToken);
}
finally
{
ctr.Dispose();
}
}
public static async Task <(Socket, Stream)> ConnectAsync(string host, int port, ConfigureSocket configureSocket, CancellationToken cancellationToken)
{
// Rather than creating a new Socket and calling ConnectAsync on it, we use the static
// Socket.ConnectAsync with a SocketAsyncEventArgs, as we can then use Socket.CancelConnectAsync
// to cancel it if needed. Rent or allocate one.
ConnectEventArgs saea;
if (!s_connectEventArgs.TryDequeue(out saea))
{
saea = new ConnectEventArgs();
}
try
{
saea.Initialize(cancellationToken);
// Configure which server to which to connect.
saea.RemoteEndPoint = new DnsEndPoint(host, port);
// Initiate the connection.
if (Socket.ConnectAsync(SocketType.Stream, ProtocolType.Tcp, saea))
{
// Connect completing asynchronously. Enable it to be canceled and wait for it.
using (cancellationToken.Register(s => Socket.CancelConnectAsync((SocketAsyncEventArgs)s), saea))
{
await saea.Builder.Task.ConfigureAwait(false);
}
}
else if (saea.SocketError != SocketError.Success)
{
// Connect completed synchronously but unsuccessfully.
throw new SocketException((int)saea.SocketError);
}
Debug.Assert(saea.SocketError == SocketError.Success, $"Expected Success, got {saea.SocketError}.");
Debug.Assert(saea.ConnectSocket != null, "Expected non-null socket");
// Configure the socket and return a stream for it.
Socket socket = saea.ConnectSocket;
socket.NoDelay = true;
configureSocket(socket);
return(socket, new NetworkStream(socket, ownsSocket: true));
}
catch (Exception error)
{
throw CancellationHelper.ShouldWrapInOperationCanceledException(error, cancellationToken) ?
CancellationHelper.CreateOperationCanceledException(error, cancellationToken) :
new HttpRequestException(error.Message, error);
}
finally
{
// Pool the event args, or if the pool is full, dispose of it.
saea.Clear();
if (s_connectEventArgs.Count <= Math.Max(2, Environment.ProcessorCount))
{
s_connectEventArgs.Enqueue(saea);
}
else
{
saea.Dispose();
}
}
}
public override async ValueTask <int> ReadAsync(Memory <byte> buffer, CancellationToken cancellationToken)
{
CancellationHelper.ThrowIfCancellationRequested(cancellationToken);
if (_connection == null || buffer.Length == 0)
{
// Response body fully consumed or the caller didn't ask for any data
return(0);
}
ValueTask <int> readTask = _connection.ReadAsync(buffer);
int bytesRead;
if (readTask.IsCompletedSuccessfully)
{
bytesRead = readTask.Result;
}
else
{
CancellationTokenRegistration ctr = _connection.RegisterCancellation(cancellationToken);
try
{
bytesRead = await readTask.ConfigureAwait(false);
}
#if MONOTOUCH_WATCH
catch (Exception exc)
{
if (CancellationHelper.ShouldWrapInOperationCanceledException(exc, cancellationToken))
{
throw CancellationHelper.CreateOperationCanceledException(exc, cancellationToken);
}
throw;
}
#else
catch (Exception exc) when(CancellationHelper.ShouldWrapInOperationCanceledException(exc, cancellationToken))
{
throw CancellationHelper.CreateOperationCanceledException(exc, cancellationToken);
}
#endif
finally
{
ctr.Dispose();
}
}
if (bytesRead == 0)
{
// If cancellation is requested and tears down the connection, it could cause the read
// to return 0, which would otherwise signal the end of the data, but that would lead
// the caller to think that it actually received all of the data, rather than it ending
// early due to cancellation. So we prioritize cancellation in this race condition, and
// if we read 0 bytes and then find that cancellation has requested, we assume cancellation
// was the cause and throw.
CancellationHelper.ThrowIfCancellationRequested(cancellationToken);
// We cannot reuse this connection, so close it.
_connection.Dispose();
_connection = null;
return(0);
}
return(bytesRead);
}
public static async ValueTask <(Socket, Stream)> ConnectAsync(string host, int port, CancellationToken cancellationToken)
{
try
{
// Rather than creating a new Socket and calling ConnectAsync on it, we use the static
// Socket.ConnectAsync with a SocketAsyncEventArgs, as we can then use Socket.CancelConnectAsync
// to cancel it if needed.
using (var saea = new BuilderAndCancellationTokenSocketAsyncEventArgs(cancellationToken))
{
// Configure which server to which to connect.
saea.RemoteEndPoint = IPAddress.TryParse(host, out IPAddress address) ?
(EndPoint) new IPEndPoint(address, port) :
new DnsEndPoint(host, port);
// Hook up a callback that'll complete the Task when the operation completes.
saea.Completed += (s, e) =>
{
var csaea = (BuilderAndCancellationTokenSocketAsyncEventArgs)e;
switch (e.SocketError)
{
case SocketError.Success:
csaea.Builder.SetResult();
break;
case SocketError.OperationAborted:
case SocketError.ConnectionAborted:
if (csaea.CancellationToken.IsCancellationRequested)
{
csaea.Builder.SetException(CancellationHelper.CreateOperationCanceledException(null, csaea.CancellationToken));
break;
}
goto default;
default:
csaea.Builder.SetException(new SocketException((int)e.SocketError));
break;
}
};
// Initiate the connection.
if (Socket.ConnectAsync(SocketType.Stream, ProtocolType.Tcp, saea))
{
// Connect completing asynchronously. Enable it to be canceled and wait for it.
using (cancellationToken.Register(s => Socket.CancelConnectAsync((SocketAsyncEventArgs)s), saea))
{
await saea.Builder.Task.ConfigureAwait(false);
}
}
else if (saea.SocketError != SocketError.Success)
{
// Connect completed synchronously but unsuccessfully.
throw new SocketException((int)saea.SocketError);
}
Debug.Assert(saea.SocketError == SocketError.Success, $"Expected Success, got {saea.SocketError}.");
Debug.Assert(saea.ConnectSocket != null, "Expected non-null socket");
// Configure the socket and return a stream for it.
Socket socket = saea.ConnectSocket;
socket.NoDelay = true;
return(socket, new NetworkStream(socket, ownsSocket: true));
}
}
catch (Exception error)
{
throw CancellationHelper.ShouldWrapInOperationCanceledException(error, cancellationToken) ?
CancellationHelper.CreateOperationCanceledException(error, cancellationToken) :
new HttpRequestException(error.Message, error);
}
}
