public async Task ConnectAsync(Uri uri, CancellationToken cancellationToken, ClientWebSocketOptions options)
{
_operation.InterlockedCheckAndUpdateState(WebSocketState.Connecting, s_validConnectStates);
using (CancellationTokenRegistration ctr = ThrowOrRegisterCancellation(cancellationToken))
{
lock (_operation.Lock)
{
_operation.CheckValidState(s_validConnectingStates);
// Must grab lock until RequestHandle is populated, otherwise we risk resource leaks on Abort.
//
// TODO (Issue 2506): Alternatively, release the lock between WinHTTP operations and check, under lock, that the
// state is still valid to continue operation.
_operation.SessionHandle = InitializeWinHttp(options);
_operation.ConnectionHandle = Interop.WinHttp.WinHttpConnectWithCallback(
_operation.SessionHandle,
uri.IdnHost,
(ushort)uri.Port,
0);
ThrowOnInvalidHandle(_operation.ConnectionHandle);
bool secureConnection = uri.Scheme == UriScheme.Https || uri.Scheme == UriScheme.Wss;
_operation.RequestHandle = Interop.WinHttp.WinHttpOpenRequestWithCallback(
_operation.ConnectionHandle,
"GET",
uri.PathAndQuery,
null,
Interop.WinHttp.WINHTTP_NO_REFERER,
null,
secureConnection ? Interop.WinHttp.WINHTTP_FLAG_SECURE : 0);
ThrowOnInvalidHandle(_operation.RequestHandle);
_operation.IncrementHandlesOpenWithCallback();
if (!Interop.WinHttp.WinHttpSetOption(
_operation.RequestHandle,
Interop.WinHttp.WINHTTP_OPTION_UPGRADE_TO_WEB_SOCKET,
IntPtr.Zero,
0))
{
WinHttpException.ThrowExceptionUsingLastError();
}
// We need the address of the IntPtr to the GCHandle.
IntPtr context = _operation.ToIntPtr();
IntPtr contextAddress;
unsafe
{
contextAddress = (IntPtr)(void *)&context;
}
if (!Interop.WinHttp.WinHttpSetOption(
_operation.RequestHandle,
Interop.WinHttp.WINHTTP_OPTION_CONTEXT_VALUE,
contextAddress,
(uint)IntPtr.Size))
{
WinHttpException.ThrowExceptionUsingLastError();
}
const uint notificationFlags =
Interop.WinHttp.WINHTTP_CALLBACK_FLAG_ALL_COMPLETIONS |
Interop.WinHttp.WINHTTP_CALLBACK_FLAG_HANDLES |
Interop.WinHttp.WINHTTP_CALLBACK_FLAG_SECURE_FAILURE;
if (Interop.WinHttp.WinHttpSetStatusCallback(
_operation.RequestHandle,
WinHttpWebSocketCallback.s_StaticCallbackDelegate,
notificationFlags,
IntPtr.Zero) == (IntPtr)Interop.WinHttp.WINHTTP_INVALID_STATUS_CALLBACK)
{
WinHttpException.ThrowExceptionUsingLastError();
}
_operation.RequestHandle.AttachCallback();
// We need to pin the operation object at this point in time since the WinHTTP callback
// has been fully wired to the request handle and the operation object has been set as
// the context value of the callback. Any notifications from activity on the handle will
// result in the callback being called with the context value.
_operation.Pin();
AddRequestHeaders(uri, options);
_operation.TcsUpgrade = new TaskCompletionSource <bool>();
}
await InternalSendWsUpgradeRequestAsync().ConfigureAwait(false);
await InternalReceiveWsUpgradeResponse().ConfigureAwait(false);
lock (_operation.Lock)
{
VerifyUpgradeResponse();
ThrowOnInvalidConnectState();
_operation.WebSocketHandle =
Interop.WinHttp.WinHttpWebSocketCompleteUpgrade(_operation.RequestHandle, IntPtr.Zero);
ThrowOnInvalidHandle(_operation.WebSocketHandle);
_operation.IncrementHandlesOpenWithCallback();
// We need the address of the IntPtr to the GCHandle.
IntPtr context = _operation.ToIntPtr();
IntPtr contextAddress;
unsafe
{
contextAddress = (IntPtr)(void *)&context;
}
if (!Interop.WinHttp.WinHttpSetOption(
_operation.WebSocketHandle,
Interop.WinHttp.WINHTTP_OPTION_CONTEXT_VALUE,
contextAddress,
(uint)IntPtr.Size))
{
WinHttpException.ThrowExceptionUsingLastError();
}
_operation.WebSocketHandle.AttachCallback();
_operation.UpdateState(WebSocketState.Open);
if (_operation.RequestHandle != null)
{
_operation.RequestHandle.Dispose();
// RequestHandle will be set to null in the callback.
}
_operation.TcsUpgrade = null;
ctr.Dispose();
}
}
}
