public void Dispose()
{
if (!_disposed)
{
_disposed = true;
if (_sessionHandle != null && !_sessionHandle.IsInvalid)
{
SafeWinHttpHandle.DisposeAndClearHandle(ref _sessionHandle);
}
}
}
protected override void Dispose(bool disposing)
{
if (disposing && !_disposed)
{
_disposed = true;
_requestHandle.DangerousRelease();
SafeWinHttpHandle.DisposeAndClearHandle(ref _requestHandle);
}
base.Dispose(disposing);
}
protected override void Dispose(bool disposing)
{
if (!_disposed)
{
_disposed = true;
if (disposing && _sessionHandle != null)
{
SafeWinHttpHandle.DisposeAndClearHandle(ref _sessionHandle);
}
}
base.Dispose(disposing);
}
private async void StartRequest(object obj)
{
WinHttpRequestState state = (WinHttpRequestState)obj;
bool secureConnection = false;
HttpResponseMessage responseMessage = null;
Exception savedException = null;
SafeWinHttpHandle connectHandle = null;
if (state.CancellationToken.IsCancellationRequested)
{
state.Tcs.TrySetCanceled(state.CancellationToken);
return;
}
try
{
EnsureSessionHandleExists(state);
SetSessionHandleOptions();
// Specify an HTTP server.
connectHandle = Interop.WinHttp.WinHttpConnect(
_sessionHandle,
state.RequestMessage.RequestUri.Host,
(ushort)state.RequestMessage.RequestUri.Port,
0);
ThrowOnInvalidHandle(connectHandle);
connectHandle.SetParentHandle(_sessionHandle);
if (state.RequestMessage.RequestUri.Scheme == UriScheme.Https)
{
secureConnection = true;
}
else
{
secureConnection = false;
}
// Create an HTTP request handle.
state.RequestHandle = Interop.WinHttp.WinHttpOpenRequest(
connectHandle,
state.RequestMessage.Method.Method,
state.RequestMessage.RequestUri.PathAndQuery,
null,
Interop.WinHttp.WINHTTP_NO_REFERER,
Interop.WinHttp.WINHTTP_DEFAULT_ACCEPT_TYPES,
secureConnection ? Interop.WinHttp.WINHTTP_FLAG_SECURE : 0);
ThrowOnInvalidHandle(state.RequestHandle);
state.RequestHandle.SetParentHandle(connectHandle);
// Set callback function.
SetStatusCallback(state.RequestHandle, WinHttpRequestCallback.StaticCallbackDelegate);
// Set needed options on the request handle.
SetRequestHandleOptions(state);
bool chunkedModeForSend = IsChunkedModeForSend(state.RequestMessage);
AddRequestHeaders(
state.RequestHandle,
state.RequestMessage,
_cookieUsePolicy == CookieUsePolicy.UseSpecifiedCookieContainer ? _cookieContainer : null);
uint proxyAuthScheme = 0;
uint serverAuthScheme = 0;
state.RetryRequest = false;
// The only way to abort pending async operations in WinHTTP is to close the WinHTTP handle.
// We will detect a cancellation request on the cancellation token by registering a callback.
// If the callback is invoked, then we begin the abort process by disposing the handle. This
// will have the side-effect of WinHTTP cancelling any pending I/O and accelerating its callbacks
// on the handle and thus releasing the awaiting tasks in the loop below. This helps to provide
// a more timely, cooperative, cancellation pattern.
using (state.CancellationToken.Register(s => ((WinHttpRequestState)s).RequestHandle.Dispose(), state))
{
do
{
_authHelper.PreAuthenticateRequest(state, proxyAuthScheme);
await InternalSendRequestAsync(state).ConfigureAwait(false);
if (state.RequestMessage.Content != null)
{
await InternalSendRequestBodyAsync(state, chunkedModeForSend).ConfigureAwait(false);
}
bool receivedResponse = await InternalReceiveResponseHeadersAsync(state).ConfigureAwait(false);
if (receivedResponse)
{
_authHelper.CheckResponseForAuthentication(
state,
ref proxyAuthScheme,
ref serverAuthScheme);
}
} while (state.RetryRequest);
}
state.CancellationToken.ThrowIfCancellationRequested();
responseMessage = WinHttpResponseParser.CreateResponseMessage(state, _doManualDecompressionCheck);
// Since the headers have been read, set the "receive" timeout to be based on each read
// call of the response body data. WINHTTP_OPTION_RECEIVE_TIMEOUT sets a timeout on each
// lower layer winsock read.
uint optionData = (uint)_receiveDataTimeout.TotalMilliseconds;
SetWinHttpOption(state.RequestHandle, Interop.WinHttp.WINHTTP_OPTION_RECEIVE_TIMEOUT, ref optionData);
}
catch (Exception ex)
{
if (state.SavedException != null)
{
savedException = state.SavedException;
}
else
{
savedException = ex;
}
}
finally
{
SafeWinHttpHandle.DisposeAndClearHandle(ref connectHandle);
}
// Move the main task to a terminal state. This releases any callers of SendAsync() that are awaiting.
if (responseMessage != null)
{
state.Tcs.TrySetResult(responseMessage);
}
else
{
HandleAsyncException(state, savedException);
}
}