WIP: Improve Async Paths #335
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,164 @@ | ||
| // Licensed to the .NET Foundation under one or more agreements. | ||
| // The .NET Foundation licenses this file to you under the MIT license. | ||
| // See the LICENSE file in the project root for more information. | ||
|
|
||
| using System; | ||
| using System.Threading; | ||
| using System.Threading.Tasks; | ||
|
|
||
| namespace Microsoft.Data.SqlClient.SNI | ||
| { | ||
| internal sealed partial class SslOverTdsStream | ||
| { | ||
| public override int Read(byte[] buffer, int offset, int count) | ||
| => ReadInternal(new Memory<byte>(buffer, offset, count), default, async: false).GetAwaiter().GetResult(); | ||
|
|
||
| public override Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken token) | ||
| => ReadInternal(new Memory<byte>(buffer, offset, count), token, async: true).AsTask(); | ||
|
|
||
| public override ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken cancellationToken) | ||
| => ReadInternal(buffer, cancellationToken, async: true); | ||
|
|
||
| public override void Write(byte[] buffer, int offset, int count) | ||
| => WriteInternal(new ReadOnlyMemory<byte>(buffer, offset, count), default, async: true).GetAwaiter().GetResult(); | ||
|
|
||
| public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken token) | ||
| => WriteInternal(new ReadOnlyMemory<byte>(buffer, offset, count), token, async: true).AsTask(); | ||
|
|
||
| public override ValueTask WriteAsync(ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken) | ||
| => WriteInternal(buffer, cancellationToken, async: true); | ||
|
|
||
| /// <summary> | ||
| /// Read Internal is called synchronosly when async is false | ||
| /// </summary> | ||
| private async ValueTask<int> ReadInternal(Memory<byte> buffer, CancellationToken token, bool async) | ||
| { | ||
| int readBytes = 0; | ||
| int count = buffer.Length; | ||
| byte[] packetData = new byte[count < TdsEnums.HEADER_LEN ? TdsEnums.HEADER_LEN : count]; | ||
|
|
||
| if (_encapsulate) | ||
| { | ||
| if (_packetBytes == 0) | ||
| { | ||
| // Account for split packets | ||
| while (readBytes < TdsEnums.HEADER_LEN) | ||
| { | ||
| readBytes += async ? | ||
|
There was a problem hiding this comment. This can infinite loop if the connection is closed and the read returns 0 and doesn't throw, Are closed connections guaranteed to throw or return non-zero? There was a problem hiding this comment. Hmm... the existing loop also has this issue. Will fix in both. Good spot There was a problem hiding this comment. Someone else mentioned it elsewhere before I just haven't got around to looking at it in any depth yet so since you're here anyway I thought it worth mentioning. There may not be a clear way to "fix" it from what I remember. I'm not sure what should happen if you end up in a partial packet read because it's below ssl stream which is going to try and decode anything you return in the buffer which can error that looks like a transport error when in fact it's connection closed. See what you think. |
||
| await _stream.ReadAsync(packetData, readBytes, TdsEnums.HEADER_LEN - readBytes, token).ConfigureAwait(false) : | ||
| _stream.Read(packetData, readBytes, TdsEnums.HEADER_LEN - readBytes); | ||
| } | ||
|
|
||
| _packetBytes = (packetData[TdsEnums.HEADER_LEN_FIELD_OFFSET] << 8) | packetData[TdsEnums.HEADER_LEN_FIELD_OFFSET + 1]; | ||
| _packetBytes -= TdsEnums.HEADER_LEN; | ||
| } | ||
|
|
||
| if (count > _packetBytes) | ||
| { | ||
| count = _packetBytes; | ||
| } | ||
| } | ||
|
|
||
| readBytes = async ? | ||
| await _stream.ReadAsync(new Memory<byte>(packetData, 0, count), token).ConfigureAwait(false) : | ||
| _stream.Read(packetData.AsSpan(0, count)); | ||
|
|
||
| if (_encapsulate) | ||
| { | ||
| _packetBytes -= readBytes; | ||
| } | ||
|
|
||
| packetData.AsSpan(0, readBytes).CopyTo(buffer.Span); | ||
| return readBytes; | ||
| } | ||
|
|
||
| /// <summary> | ||
| /// The internal write method calls Sync APIs when Async flag is false | ||
| /// </summary> | ||
| private async ValueTask WriteInternal(ReadOnlyMemory<byte> buffer, CancellationToken token, bool async) | ||
| { | ||
| int count = buffer.Length; | ||
| int currentOffset = 0; | ||
|
|
||
| while (count > 0) | ||
| { | ||
| int currentCount; | ||
| // During the SSL negotiation phase, SSL is tunnelled over TDS packet type 0x12. After | ||
| // negotiation, the underlying socket only sees SSL frames. | ||
| // | ||
| if (_encapsulate) | ||
| { | ||
| if (count > PACKET_SIZE_WITHOUT_HEADER) | ||
| { | ||
| currentCount = PACKET_SIZE_WITHOUT_HEADER; | ||
| } | ||
| else | ||
| { | ||
| currentCount = count; | ||
| } | ||
|
|
||
| count -= currentCount; | ||
|
|
||
| // Prepend buffer data with TDS prelogin header | ||
| byte[] combinedBuffer = new byte[TdsEnums.HEADER_LEN + currentCount]; | ||
|
|
||
| // We can only send 4088 bytes in one packet. Header[1] is set to 1 if this is a | ||
| // partial packet (whether or not count != 0). | ||
| // | ||
| combinedBuffer[0] = PRELOGIN_PACKET_TYPE; | ||
| combinedBuffer[1] = (byte)(count > 0 ? 0 : 1); | ||
| combinedBuffer[2] = (byte)((currentCount + TdsEnums.HEADER_LEN) / 0x100); | ||
| combinedBuffer[3] = (byte)((currentCount + TdsEnums.HEADER_LEN) % 0x100); | ||
| combinedBuffer[4] = 0; | ||
| combinedBuffer[5] = 0; | ||
| combinedBuffer[6] = 0; | ||
| combinedBuffer[7] = 0; | ||
|
|
||
| CopyToBuffer(combinedBuffer, buffer.Span.Slice(currentOffset)); | ||
|
|
||
| if (async) | ||
| { | ||
| await _stream.WriteAsync(combinedBuffer, 0, combinedBuffer.Length, token).ConfigureAwait(false); | ||
| } | ||
| else | ||
| { | ||
| _stream.Write(combinedBuffer.AsSpan()); | ||
| } | ||
| } | ||
| else | ||
| { | ||
| currentCount = count; | ||
| count = 0; | ||
|
|
||
| if (async) | ||
| { | ||
| await _stream.WriteAsync(buffer.Slice(currentOffset, currentCount), token).ConfigureAwait(false); | ||
| } | ||
| else | ||
| { | ||
| _stream.Write(buffer.Span.Slice(currentOffset, currentCount)); | ||
| } | ||
| } | ||
|
|
||
| if (async) | ||
| { | ||
| await _stream.FlushAsync().ConfigureAwait(false); | ||
| } | ||
| else | ||
| { | ||
| _stream.Flush(); | ||
| } | ||
|
|
||
| currentOffset += currentCount; | ||
| } | ||
|
|
||
| void CopyToBuffer(byte[] combinedBuffer, ReadOnlySpan<byte> span) | ||
| { | ||
| for (int i = TdsEnums.HEADER_LEN; i < combinedBuffer.Length; i++) | ||
| { | ||
| combinedBuffer[i] = span[i - TdsEnums.HEADER_LEN]; | ||
| } | ||
| } | ||
| } | ||
| } | ||
| } | ||
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The old code
(t.Status & TaskStatus.RanToCompletion) != 0inSNIPacket.NetStandard.cslooks strange, sinceTaskStatusis not a flag, so this will even be true forTaskStatus.WaitingForActivation, maybe it should bet.Status == TaskStatus.RanToCompletioninstead to follow the logic in netcoreapp?There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Nice catch. Looking at the enum values that'll let fault and cancel through. I'm surprised visual studio doesn't complain about doing bitwise operations on a non-[Flag] enum.