internal unsafe Task SendFileAsyncCore(string fileName, long offset, long?count, CancellationToken cancellationToken)
{
_requestContext.Response.Start();
UnsafeNclNativeMethods.HttpApi.HTTP_FLAGS flags = ComputeLeftToWrite();
if (count == 0 && _leftToWrite != 0)
{
return(Helpers.CompletedTask());
}
if (_leftToWrite >= 0 && count > _leftToWrite)
{
throw new InvalidOperationException(Resources.Exception_TooMuchWritten);
}
// TODO: Verbose log
if (cancellationToken.IsCancellationRequested)
{
return(Helpers.CanceledTask <int>());
}
var cancellationRegistration = default(CancellationTokenRegistration);
if (cancellationToken.CanBeCanceled)
{
cancellationRegistration = cancellationToken.Register(RequestContext.AbortDelegate, _requestContext);
}
uint statusCode;
uint bytesSent = 0;
bool startedSending = _requestContext.Response.HasStartedSending;
var chunked = _requestContext.Response.BoundaryType == BoundaryType.Chunked;
ResponseStreamAsyncResult asyncResult = new ResponseStreamAsyncResult(this, fileName, offset, count, chunked, cancellationRegistration);
long bytesWritten;
if (chunked)
{
bytesWritten = 0;
}
else if (count.HasValue)
{
bytesWritten = count.Value;
}
else
{
bytesWritten = asyncResult.FileLength - offset;
}
// Update _leftToWrite now so we can queue up additional calls to SendFileAsync.
flags |= _leftToWrite == bytesWritten ? HttpApi.HTTP_FLAGS.NONE : HttpApi.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA;
UpdateWritenCount((uint)bytesWritten);
try
{
if (!startedSending)
{
statusCode = _requestContext.Response.SendHeaders(null, asyncResult, flags, false);
bytesSent = asyncResult.BytesSent;
}
else
{
// TODO: If opaque then include the buffer data flag.
statusCode = HttpApi.HttpSendResponseEntityBody(
_requestContext.RequestQueueHandle,
_requestContext.RequestId,
(uint)flags,
asyncResult.DataChunkCount,
asyncResult.DataChunks,
&bytesSent,
SafeLocalFree.Zero,
0,
asyncResult.NativeOverlapped,
IntPtr.Zero);
}
}
catch (Exception e)
{
LogHelper.LogException(_requestContext.Logger, "SendFileAsync", e);
asyncResult.Dispose();
Abort();
throw;
}
if (statusCode != UnsafeNclNativeMethods.ErrorCodes.ERROR_SUCCESS && statusCode != UnsafeNclNativeMethods.ErrorCodes.ERROR_IO_PENDING)
{
asyncResult.Dispose();
if (_requestContext.Server.IgnoreWriteExceptions && startedSending)
{
asyncResult.Complete();
}
else
{
Exception exception = new IOException(string.Empty, new WebListenerException((int)statusCode));
LogHelper.LogException(_requestContext.Logger, "SendFileAsync", exception);
Abort();
throw exception;
}
}
if (statusCode == ErrorCodes.ERROR_SUCCESS && WebListener.SkipIOCPCallbackOnSuccess)
{
// IO operation completed synchronously - callback won't be called to signal completion.
asyncResult.IOCompleted(statusCode, bytesSent);
}
// Last write, cache it for special cancellation handling.
if ((flags & HttpApi.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA) == 0)
{
_lastWrite = asyncResult;
}
return(asyncResult.Task);
}
// Simpler than Flush because it will never be called at the end of the request from Dispose.
public unsafe override Task FlushAsync(CancellationToken cancellationToken)
{
if (_closed)
{
return(Helpers.CompletedTask());
}
bool startedSending = _requestContext.Response.HasStartedSending;
var byteCount = _buffer.TotalBytes;
if (byteCount == 0 && startedSending)
{
// Empty flush
return(Helpers.CompletedTask());
}
var cancellationRegistration = default(CancellationTokenRegistration);
if (cancellationToken.CanBeCanceled)
{
cancellationRegistration = cancellationToken.Register(RequestContext.AbortDelegate, _requestContext);
}
var flags = ComputeLeftToWrite();
if (_leftToWrite != byteCount)
{
flags |= HttpApi.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA;
}
UpdateWritenCount((uint)byteCount);
uint statusCode = 0;
var chunked = _requestContext.Response.BoundaryType == BoundaryType.Chunked;
var asyncResult = new ResponseStreamAsyncResult(this, _buffer, chunked, cancellationRegistration);
uint bytesSent = 0;
try
{
if (!startedSending)
{
statusCode = _requestContext.Response.SendHeaders(null, asyncResult, flags, false);
bytesSent = asyncResult.BytesSent;
}
else
{
statusCode = HttpApi.HttpSendResponseEntityBody(
_requestContext.RequestQueueHandle,
_requestContext.RequestId,
(uint)flags,
asyncResult.DataChunkCount,
asyncResult.DataChunks,
&bytesSent,
SafeLocalFree.Zero,
0,
asyncResult.NativeOverlapped,
IntPtr.Zero);
}
}
catch (Exception e)
{
LogHelper.LogException(_requestContext.Logger, "FlushAsync", e);
asyncResult.Dispose();
Abort();
throw;
}
if (statusCode != ErrorCodes.ERROR_SUCCESS && statusCode != ErrorCodes.ERROR_IO_PENDING)
{
asyncResult.Dispose();
if (_requestContext.Server.IgnoreWriteExceptions && startedSending)
{
asyncResult.Complete();
}
else
{
Exception exception = new IOException(string.Empty, new WebListenerException((int)statusCode));
LogHelper.LogException(_requestContext.Logger, "FlushAsync", exception);
Abort();
throw exception;
}
}
if (statusCode == ErrorCodes.ERROR_SUCCESS && WebListener.SkipIOCPCallbackOnSuccess)
{
// IO operation completed synchronously - callback won't be called to signal completion.
asyncResult.IOCompleted(statusCode, bytesSent);
}
// Last write, cache it for special cancellation handling.
if ((flags & HttpApi.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA) == 0)
{
_lastWrite = asyncResult;
}
return(asyncResult.Task);
}