// The final Content-Length async write can only be Canceled by CancelIoEx.
// Sync can only be Canceled by CancelSynchronousIo, but we don't attempt this right now.
internal unsafe void CancelLastWrite()
{
ResponseStreamAsyncResult?asyncState = _lastWrite;
if (asyncState != null && !asyncState.IsCompleted)
{
UnsafeNclNativeMethods.CancelIoEx(RequestQueueHandle, asyncState.NativeOverlapped !);
}
}
// Simpler than Flush because it will never be called at the end of the request from Dispose.
private unsafe Task FlushInternalAsync(ArraySegment <byte> data, CancellationToken cancellationToken)
{
if (_skipWrites)
{
return(Task.CompletedTask);
}
var started = _requestContext.Response.HasStarted;
if (data.Count == 0 && started)
{
// No data to send and we've already sent the headers
return(Task.CompletedTask);
}
if (cancellationToken.IsCancellationRequested)
{
Abort(ThrowWriteExceptions);
return(Task.FromCanceled <int>(cancellationToken));
}
// Make sure all validation is performed before this computes the headers
var flags = ComputeLeftToWrite(data.Count);
uint statusCode;
var chunked = _requestContext.Response.BoundaryType == BoundaryType.Chunked;
var asyncResult = new ResponseStreamAsyncResult(this, data, chunked, cancellationToken);
uint bytesSent = 0;
try
{
if (!started)
{
statusCode = _requestContext.Response.SendHeaders(null, asyncResult, flags, false);
bytesSent = asyncResult.BytesSent;
}
else
{
statusCode = HttpApi.HttpSendResponseEntityBody(
RequestQueueHandle,
RequestId,
(uint)flags,
asyncResult.DataChunkCount,
asyncResult.DataChunks,
&bytesSent,
IntPtr.Zero,
0,
asyncResult.NativeOverlapped !,
IntPtr.Zero);
}
}
catch (Exception e)
{
Log.ErrorWhenFlushAsync(Logger, e);
asyncResult.Dispose();
Abort();
throw;
}
if (statusCode != ErrorCodes.ERROR_SUCCESS && statusCode != ErrorCodes.ERROR_IO_PENDING)
{
if (cancellationToken.IsCancellationRequested)
{
Log.WriteFlushCancelled(Logger, statusCode);
asyncResult.Cancel(ThrowWriteExceptions);
}
else if (ThrowWriteExceptions)
{
asyncResult.Dispose();
Exception exception = new IOException(string.Empty, new HttpSysException((int)statusCode));
Log.ErrorWhenFlushAsync(Logger, exception);
Abort();
throw exception;
}
else
{
// Abort the request but do not close the stream, let future writes complete silently
Log.WriteErrorIgnored(Logger, statusCode);
asyncResult.FailSilently();
}
}
if (statusCode == ErrorCodes.ERROR_SUCCESS && HttpSysListener.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 & HttpApiTypes.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA) == 0)
{
_lastWrite = asyncResult;
}
return(asyncResult.Task);
}
internal unsafe Task SendFileAsyncCore(string fileName, long offset, long?count, CancellationToken cancellationToken)
{
if (_skipWrites)
{
return(Task.CompletedTask);
}
var started = _requestContext.Response.HasStarted;
if (count == 0 && started)
{
// No data to send and we've already sent the headers
return(Task.CompletedTask);
}
if (cancellationToken.IsCancellationRequested)
{
Abort(ThrowWriteExceptions);
return(Task.FromCanceled <int>(cancellationToken));
}
// We are setting buffer size to 1 to prevent FileStream from allocating it's internal buffer
// It's too expensive to validate anything before opening the file. Open the file and then check the lengths.
var fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, bufferSize: 1,
options: FileOptions.Asynchronous | FileOptions.SequentialScan); // Extremely expensive.
try
{
var length = fileStream.Length; // Expensive, only do it once
if (!count.HasValue)
{
count = length - offset;
}
if (offset < 0 || offset > length)
{
throw new ArgumentOutOfRangeException(nameof(offset), offset, string.Empty);
}
if (count < 0 || count > length - offset)
{
throw new ArgumentOutOfRangeException(nameof(count), count, string.Empty);
}
CheckWriteCount(count);
}
catch
{
fileStream.Dispose();
throw;
}
// Make sure all validation is performed before this computes the headers
var flags = ComputeLeftToWrite(count.Value);
uint statusCode;
uint bytesSent = 0;
var chunked = _requestContext.Response.BoundaryType == BoundaryType.Chunked;
var asyncResult = new ResponseStreamAsyncResult(this, fileStream, offset, count.Value, chunked, cancellationToken);
try
{
if (!started)
{
statusCode = _requestContext.Response.SendHeaders(null, asyncResult, flags, false);
bytesSent = asyncResult.BytesSent;
}
else
{
// TODO: If opaque then include the buffer data flag.
statusCode = HttpApi.HttpSendResponseEntityBody(
RequestQueueHandle,
RequestId,
(uint)flags,
asyncResult.DataChunkCount,
asyncResult.DataChunks,
&bytesSent,
IntPtr.Zero,
0,
asyncResult.NativeOverlapped !,
IntPtr.Zero);
}
}
catch (Exception e)
{
Log.FileSendAsyncError(Logger, e);
asyncResult.Dispose();
Abort();
throw;
}
if (statusCode != UnsafeNclNativeMethods.ErrorCodes.ERROR_SUCCESS && statusCode != UnsafeNclNativeMethods.ErrorCodes.ERROR_IO_PENDING)
{
if (cancellationToken.IsCancellationRequested)
{
Log.FileSendAsyncCancelled(Logger, statusCode);
asyncResult.Cancel(ThrowWriteExceptions);
}
else if (ThrowWriteExceptions)
{
asyncResult.Dispose();
var exception = new IOException(string.Empty, new HttpSysException((int)statusCode));
Log.FileSendAsyncError(Logger, exception);
Abort();
throw exception;
}
else
{
// Abort the request but do not close the stream, let future writes complete
Log.FileSendAsyncErrorIgnored(Logger, statusCode);
asyncResult.FailSilently();
}
}
if (statusCode == ErrorCodes.ERROR_SUCCESS && HttpSysListener.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 & HttpApiTypes.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_MORE_DATA) == 0)
{
_lastWrite = asyncResult;
}
return(asyncResult.Task);
}
/*
* 12.3
* HttpSendHttpResponse() and HttpSendResponseEntityBody() Flag Values.
* The following flags can be used on calls to HttpSendHttpResponse() and HttpSendResponseEntityBody() API calls:
*
#define HTTP_SEND_RESPONSE_FLAG_DISCONNECT 0x00000001
#define HTTP_SEND_RESPONSE_FLAG_MORE_DATA 0x00000002
#define HTTP_SEND_RESPONSE_FLAG_RAW_HEADER 0x00000004
#define HTTP_SEND_RESPONSE_FLAG_VALID 0x00000007
*
* HTTP_SEND_RESPONSE_FLAG_DISCONNECT:
* specifies that the network connection should be disconnected immediately after
* sending the response, overriding the HTTP protocol's persistent connection features.
* HTTP_SEND_RESPONSE_FLAG_MORE_DATA:
* specifies that additional entity body data will be sent by the caller. Thus,
* the last call HttpSendResponseEntityBody for a RequestId, will have this flag reset.
* HTTP_SEND_RESPONSE_RAW_HEADER:
* specifies that a caller of HttpSendResponseEntityBody() is intentionally omitting
* a call to HttpSendHttpResponse() in order to bypass normal header processing. The
* actual HTTP header will be generated by the application and sent as entity body.
* This flag should be passed on the first call to HttpSendResponseEntityBody, and
* not after. Thus, flag is not applicable to HttpSendHttpResponse.
*/
// TODO: Consider using HTTP_SEND_RESPONSE_RAW_HEADER with HttpSendResponseEntityBody instead of calling HttpSendHttpResponse.
// This will give us more control of the bytes that hit the wire, including encodings, HTTP 1.0, etc..
// It may also be faster to do this work in managed code and then pass down only one buffer.
// What would we loose by bypassing HttpSendHttpResponse?
//
// TODO: Consider using the HTTP_SEND_RESPONSE_FLAG_BUFFER_DATA flag for most/all responses rather than just Opaque.
internal unsafe uint SendHeaders(HttpApiTypes.HTTP_DATA_CHUNK[]?dataChunks,
ResponseStreamAsyncResult?asyncResult,
HttpApiTypes.HTTP_FLAGS flags,
bool isOpaqueUpgrade)
{
Debug.Assert(!HasStarted, "HttpListenerResponse::SendHeaders()|SentHeaders is true.");
_responseState = ResponseState.Started;
var reasonPhrase = GetReasonPhrase(StatusCode);
uint statusCode;
uint bytesSent;
List <GCHandle>?pinnedHeaders = SerializeHeaders(isOpaqueUpgrade);
try
{
if (dataChunks != null)
{
if (pinnedHeaders == null)
{
pinnedHeaders = new List <GCHandle>();
}
var handle = GCHandle.Alloc(dataChunks, GCHandleType.Pinned);
pinnedHeaders.Add(handle);
_nativeResponse.Response_V1.EntityChunkCount = (ushort)dataChunks.Length;
_nativeResponse.Response_V1.pEntityChunks = (HttpApiTypes.HTTP_DATA_CHUNK *)handle.AddrOfPinnedObject();
}
else if (asyncResult != null && asyncResult.DataChunks != null)
{
_nativeResponse.Response_V1.EntityChunkCount = asyncResult.DataChunkCount;
_nativeResponse.Response_V1.pEntityChunks = asyncResult.DataChunks;
}
else
{
_nativeResponse.Response_V1.EntityChunkCount = 0;
_nativeResponse.Response_V1.pEntityChunks = null;
}
var cachePolicy = new HttpApiTypes.HTTP_CACHE_POLICY();
if (_cacheTtl.HasValue && _cacheTtl.Value > TimeSpan.Zero)
{
cachePolicy.Policy = HttpApiTypes.HTTP_CACHE_POLICY_TYPE.HttpCachePolicyTimeToLive;
cachePolicy.SecondsToLive = (uint)Math.Min(_cacheTtl.Value.Ticks / TimeSpan.TicksPerSecond, Int32.MaxValue);
}
byte[] reasonPhraseBytes = HeaderEncoding.GetBytes(reasonPhrase);
fixed(byte *pReasonPhrase = reasonPhraseBytes)
{
_nativeResponse.Response_V1.ReasonLength = (ushort)reasonPhraseBytes.Length;
_nativeResponse.Response_V1.pReason = (byte *)pReasonPhrase;
fixed(HttpApiTypes.HTTP_RESPONSE_V2 *pResponse = &_nativeResponse)
{
statusCode =
HttpApi.HttpSendHttpResponse(
RequestContext.Server.RequestQueue.Handle,
Request.RequestId,
(uint)flags,
pResponse,
&cachePolicy,
&bytesSent,
IntPtr.Zero,
0,
asyncResult == null ? SafeNativeOverlapped.Zero : asyncResult.NativeOverlapped !,
IntPtr.Zero);
// GoAway is only supported on later versions. Retry.
if (statusCode == ErrorCodes.ERROR_INVALID_PARAMETER &&
(flags & HttpApiTypes.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_GOAWAY) != 0)
{
flags &= ~HttpApiTypes.HTTP_FLAGS.HTTP_SEND_RESPONSE_FLAG_GOAWAY;
statusCode =
HttpApi.HttpSendHttpResponse(
RequestContext.Server.RequestQueue.Handle,
Request.RequestId,
(uint)flags,
pResponse,
&cachePolicy,
&bytesSent,
IntPtr.Zero,
0,
asyncResult == null ? SafeNativeOverlapped.Zero : asyncResult.NativeOverlapped !,
IntPtr.Zero);
// Succeeded without GoAway, disable them.
if (statusCode != ErrorCodes.ERROR_INVALID_PARAMETER)
{
SupportsGoAway = false;
}
}
if (asyncResult != null &&
statusCode == ErrorCodes.ERROR_SUCCESS &&
HttpSysListener.SkipIOCPCallbackOnSuccess)
{
asyncResult.BytesSent = bytesSent;
// The caller will invoke IOCompleted
}
}
}
}
finally
{
FreePinnedHeaders(pinnedHeaders);
}
return(statusCode);
}