Merge branch 'dev' into knownmethods-optimizations

.travis.yml

@@ -32,5 +32,5 @@ branches:
 before_install:
   - if test "$TRAVIS_OS_NAME" == "osx"; then brew update; brew install openssl; ln -s /usr/local/opt/openssl/lib/libcrypto.1.0.0.dylib /usr/local/lib/; ln -s /usr/local/opt/openssl/lib/libssl.1.0.0.dylib /usr/local/lib/; fi
 script:
-  - ./build.sh --quiet verify
+  - ./build.sh
   - if test "$TRAVIS_OS_NAME" != "osx"; then bash test/Microsoft.AspNetCore.Server.Kestrel.FunctionalTests/SystemdActivation/docker.sh; fi

NuGet.config

@@ -3,7 +3,6 @@
   <packageSources>
     <add key="AspNetCore" value="https://dotnet.myget.org/F/aspnetcore-ci-dev/api/v3/index.json" />
     <add key="AspNetCoreTools" value="https://dotnet.myget.org/F/aspnetcore-tools/api/v3/index.json" />
-    <add key="appveyor-bdn" value="https://ci.appveyor.com/nuget/benchmarkdotnet" />
     <add key="NuGet" value="https://api.nuget.org/v3/index.json" />
   </packageSources>
 </configuration>

appveyor.yml

@@ -8,7 +8,7 @@ branches:
     - feature/dev-si
     - /^(.*\/)?ci-.*$/
 build_script:
-  - build.cmd --quiet verify
+  - ps: .\build.ps1
 clone_depth: 1
 test: off
 deploy: off

build.ps1

@@ -33,7 +33,7 @@ cd $PSScriptRoot
 $repoFolder = $PSScriptRoot
 $env:REPO_FOLDER = $repoFolder
 
-$koreBuildZip="https://github.com/aspnet/KoreBuild/archive/feature/msbuild.zip"
+$koreBuildZip="https://github.com/aspnet/KoreBuild/archive/dev.zip"
 if ($env:KOREBUILD_ZIP)
 {
     $koreBuildZip=$env:KOREBUILD_ZIP
@@ -64,4 +64,4 @@ if (!(Test-Path $buildFolder)) {
     }
 }
 
-&"$buildFile" $args
+&"$buildFile" @args

build.sh

@@ -2,7 +2,7 @@
 repoFolder="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 cd $repoFolder
 
-koreBuildZip="https://github.com/aspnet/KoreBuild/archive/feature/msbuild.zip"
+koreBuildZip="https://github.com/aspnet/KoreBuild/archive/dev.zip"
 if [ ! -z $KOREBUILD_ZIP ]; then
     koreBuildZip=$KOREBUILD_ZIP
 fi
@@ -43,4 +43,4 @@ if test ! -d $buildFolder; then
     fi
 fi
 
-$buildFile -r $repoFolder "$@"
+$buildFile -r $repoFolder "$@"

build/dependencies.props

@@ -3,5 +3,7 @@
     <NetStandardImplicitPackageVersion>1.6.1</NetStandardImplicitPackageVersion>
     <CoreFxVersion>4.3.0</CoreFxVersion>
     <LibUvVersion>1.9.1</LibUvVersion>
+    <CoreFxLabsVersion>0.1.0-*</CoreFxLabsVersion>
+    <CoreFxLabsPipelinesVersion>0.1.0-*</CoreFxLabsPipelinesVersion>
   </PropertyGroup>
 </Project>

src/Microsoft.AspNetCore.Server.Kestrel/BadHttpRequestException.cs

@@ -25,9 +25,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel
                 case RequestRejectionReason.HeadersCorruptedInvalidHeaderSequence:
                     ex = new BadHttpRequestException("Headers corrupted, invalid header sequence.", StatusCodes.Status400BadRequest);
                     break;
-                case RequestRejectionReason.HeaderLineMustNotStartWithWhitespace:
-                    ex = new BadHttpRequestException("Header line must not start with whitespace.", StatusCodes.Status400BadRequest);
-                    break;
                 case RequestRejectionReason.NoColonCharacterFoundInHeaderLine:
                     ex = new BadHttpRequestException("No ':' character found in header line.", StatusCodes.Status400BadRequest);
                     break;
@@ -40,6 +37,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel
                 case RequestRejectionReason.HeaderValueLineFoldingNotSupported:
                     ex = new BadHttpRequestException("Header value line folding not supported.", StatusCodes.Status400BadRequest);
                     break;
+                case RequestRejectionReason.InvalidRequestLine:
+                    ex = new BadHttpRequestException("Invalid request line.", StatusCodes.Status400BadRequest);
+                    break;
                 case RequestRejectionReason.MalformedRequestInvalidHeaders:
                     ex = new BadHttpRequestException("Malformed request: invalid headers.", StatusCodes.Status400BadRequest);
                     break;

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/Frame.cs

@@ -55,7 +55,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         private CancellationTokenSource _abortedCts;
         private CancellationToken? _manuallySetRequestAbortToken;
 
-        private RequestProcessingStatus _requestProcessingStatus;
+        protected RequestProcessingStatus _requestProcessingStatus;
         protected bool _keepAlive;
         protected bool _upgrade;
         private bool _canHaveBody;
@@ -982,15 +982,46 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             Output.ProducingComplete(end);
         }
 
+        public void ParseRequest(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
+        {
+            consumed = buffer.Start;
+            examined = buffer.End;
+
+            switch (_requestProcessingStatus)
+            {
+                case RequestProcessingStatus.RequestPending:
+                    if (buffer.IsEmpty)
+                    {
+                        break;
+                    }
+
+                    ConnectionControl.ResetTimeout(_requestHeadersTimeoutMilliseconds, TimeoutAction.SendTimeoutResponse);
+
+                    _requestProcessingStatus = RequestProcessingStatus.ParsingRequestLine;
+                    goto case RequestProcessingStatus.ParsingRequestLine;
+                case RequestProcessingStatus.ParsingRequestLine:
+                    if (TakeStartLine(buffer, out consumed, out examined))
+                    {
+                        buffer = buffer.Slice(consumed, buffer.End);
+
+                        _requestProcessingStatus = RequestProcessingStatus.ParsingHeaders;
+                        goto case RequestProcessingStatus.ParsingHeaders;
+                    }
+                    else
+                    {
+                        break;
+                    }
+                case RequestProcessingStatus.ParsingHeaders:
+                    if (TakeMessageHeaders(buffer, out consumed, out examined))
+                    {
+                        _requestProcessingStatus = RequestProcessingStatus.AppStarted;
+                    }
+                    break;
+            }
+        }
+
         public bool TakeStartLine(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
         {
-            if (_requestProcessingStatus == RequestProcessingStatus.RequestPending)
-            {
-                ConnectionControl.ResetTimeout(_requestHeadersTimeoutMilliseconds, TimeoutAction.SendTimeoutResponse);
-            }
-
-            _requestProcessingStatus = RequestProcessingStatus.RequestStarted;
-
             var overLength = false;
             if (buffer.Length >= ServerOptions.Limits.MaxRequestLineSize)
             {
@@ -1039,7 +1070,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             return true;
         }
 
-        public bool TakeMessageHeaders(ReadableBuffer buffer, FrameRequestHeaders requestHeaders, out ReadCursor consumed, out ReadCursor examined)
+        public bool TakeMessageHeaders(ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined)
         {
             // Make sure the buffer is limited
             bool overLength = false;
@@ -1085,7 +1116,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             if (!appCompleted)
             {
                 // Back out of header creation surface exeception in user code
-                _requestProcessingStatus = RequestProcessingStatus.RequestStarted;
+                _requestProcessingStatus = RequestProcessingStatus.AppStarted;
                 throw ex;
             }
             else
@@ -1141,18 +1172,12 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
         public void RejectRequest(RequestRejectionReason reason)
         {
-            RejectRequest(BadHttpRequestException.GetException(reason));
+            throw BadHttpRequestException.GetException(reason);
         }
 
         public void RejectRequest(RequestRejectionReason reason, string value)
         {
-            RejectRequest(BadHttpRequestException.GetException(reason, value));
+            throw BadHttpRequestException.GetException(reason, value);
-        }
-
-        private void RejectRequest(BadHttpRequestException ex)
-        {
-            Log.ConnectionBadRequest(ConnectionId, ex);
-            throw ex;
         }
 
         public void SetBadRequestState(RequestRejectionReason reason)
@@ -1162,6 +1187,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
         public void SetBadRequestState(BadHttpRequestException ex)
         {
+            Log.ConnectionBadRequest(ConnectionId, ex);
+
             if (!HasResponseStarted)
             {
                 SetErrorResponseHeaders(ex.StatusCode);
@@ -1190,20 +1217,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             Log.ApplicationError(ConnectionId, ex);
         }
 
-        public enum RequestLineStatus
-        {
-            Empty,
-            Incomplete,
-            Done
-        }
-
-        private enum RequestProcessingStatus
-        {
-            RequestPending,
-            RequestStarted,
-            ResponseStarted
-        }
-
         public void OnStartLine(HttpMethod method, HttpVersion version, Span<byte> target, Span<byte> path, Span<byte> query, Span<byte> customMethod)
         {
             // URIs are always encoded/escaped to ASCII https://tools.ietf.org/html/rfc3986#page-11
@@ -1215,7 +1228,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             if (needDecode)
             {
                 // Read raw target before mutating memory.
-                rawTarget = target.GetAsciiString() ?? string.Empty;
+                rawTarget = target.GetAsciiStringNonNullCharacters();
 
                 // URI was encoded, unescape and then parse as utf8
                 int pathLength = UrlEncoder.Decode(path, path);
@@ -1224,7 +1237,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             else
             {
                 // URI wasn't encoded, parse as ASCII
-                requestUrlPath = path.GetAsciiString() ?? string.Empty;
+                requestUrlPath = path.GetAsciiStringNonNullCharacters();
 
                 if (query.Length == 0)
                 {
@@ -1234,21 +1247,21 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                 }
                 else
                 {
-                    rawTarget = target.GetAsciiString() ?? string.Empty;
+                    rawTarget = target.GetAsciiStringNonNullCharacters();
                 }
             }
 
             var normalizedTarget = PathNormalizer.RemoveDotSegments(requestUrlPath);
             if (method != HttpMethod.Custom)
             {
-                Method = HttpUtilities.MethodToString(method) ?? String.Empty;
+                Method = HttpUtilities.MethodToString(method) ?? string.Empty;
             }
             else
             {
-                Method = customMethod.GetAsciiString() ?? string.Empty;
+                Method = customMethod.GetAsciiStringNonNullCharacters();
             }
 
-            QueryString = query.GetAsciiString() ?? string.Empty;
+            QueryString = query.GetAsciiStringNonNullCharacters();
             RawTarget = rawTarget;
             HttpVersion = HttpUtilities.VersionToString(version);
 
@@ -1276,7 +1289,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             {
                 RejectRequest(RequestRejectionReason.TooManyHeaders);
             }
-            var valueString = value.GetAsciiString() ?? string.Empty;
+            var valueString = value.GetAsciiStringNonNullCharacters();
 
             FrameRequestHeaders.Append(name, valueString);
         }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/FrameOfT.cs

@@ -3,7 +3,6 @@
 
 using System;
 using System.IO;
-using System.IO.Pipelines;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Hosting.Server;
@@ -31,16 +30,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
         /// </summary>
         public override async Task RequestProcessingAsync()
         {
-            var requestLineStatus = default(RequestLineStatus);
-
             try
             {
                 while (!_requestProcessingStopping)
                 {
-                    // If writer completes with an error Input.ReadAsyncDispatched would throw and
-                    // this would not be reset to empty. But it's required by ECONNRESET check lower in the method.
-                    requestLineStatus = RequestLineStatus.Empty;
-
                     ConnectionControl.SetTimeout(_keepAliveMilliseconds, TimeoutAction.CloseConnection);
 
                     while (!_requestProcessingStopping)
@@ -49,76 +42,44 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                         var examined = result.Buffer.End;
                         var consumed = result.Buffer.End;
 
+                        InitializeHeaders();
+
                         try
                         {
-                            if (!result.Buffer.IsEmpty)
+                            ParseRequest(result.Buffer, out consumed, out examined);
-                            {
-                                requestLineStatus = TakeStartLine(result.Buffer, out consumed, out examined)
-                                    ? RequestLineStatus.Done : RequestLineStatus.Incomplete;
-                            }
-                            else
-                            {
-                                requestLineStatus = RequestLineStatus.Empty;
-                            }
                         }
                         catch (InvalidOperationException)
                         {
-                            throw BadHttpRequestException.GetException(RequestRejectionReason.InvalidRequestLine);
+                            switch (_requestProcessingStatus)
+                            {
+                                case RequestProcessingStatus.ParsingRequestLine:
+                                    throw BadHttpRequestException.GetException(RequestRejectionReason.InvalidRequestLine);
+                                case RequestProcessingStatus.ParsingHeaders:
+                                    throw BadHttpRequestException.GetException(RequestRejectionReason.MalformedRequestInvalidHeaders);
+                            }
+                            throw;
                         }
                         finally
                         {
                             Input.Reader.Advance(consumed, examined);
                         }
 
-                        if (requestLineStatus == RequestLineStatus.Done)
+                        if (_requestProcessingStatus == RequestProcessingStatus.AppStarted)
                         {
                             break;
                         }
 
                         if (result.IsCompleted)
                         {
-                            if (requestLineStatus == RequestLineStatus.Empty)
+                            switch (_requestProcessingStatus)
                             {
-                                return;
+                                case RequestProcessingStatus.RequestPending:
+                                    return;
+                                case RequestProcessingStatus.ParsingRequestLine:
+                                    throw BadHttpRequestException.GetException(RequestRejectionReason.InvalidRequestLine);
+                                case RequestProcessingStatus.ParsingHeaders:
+                                    throw BadHttpRequestException.GetException(RequestRejectionReason.MalformedRequestInvalidHeaders);
                             }
-
-                            RejectRequest(RequestRejectionReason.InvalidRequestLine, requestLineStatus.ToString());
-                        }
-                    }
-
-                    InitializeHeaders();
-
-                    while (!_requestProcessingStopping)
-                    {
-
-                        var result = await Input.Reader.ReadAsync();
-                        var examined = result.Buffer.End;
-                        var consumed = result.Buffer.End;
-
-                        bool headersDone;
-
-                        try
-                        {
-                            headersDone = TakeMessageHeaders(result.Buffer, FrameRequestHeaders, out consumed,
-                                out examined);
-                        }
-                        catch (InvalidOperationException)
-                        {
-                            throw BadHttpRequestException.GetException(RequestRejectionReason.MalformedRequestInvalidHeaders);
-                        }
-                        finally
-                        {
-                            Input.Reader.Advance(consumed, examined);
-                        }
-
-                        if (headersDone)
-                        {
-                            break;
-                        }
-
-                        if (result.IsCompleted)
-                        {
-                            RejectRequest(RequestRejectionReason.MalformedRequestInvalidHeaders);
                         }
                     }
 
@@ -231,7 +192,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             catch (IOException ex) when (ex.InnerException is UvException)
             {
                 // Don't log ECONNRESET errors made between requests. Browsers like IE will reset connections regularly.
-                if (requestLineStatus != RequestLineStatus.Empty ||
+                if (_requestProcessingStatus != RequestProcessingStatus.RequestPending ||
                     ((UvException)ex.InnerException).StatusCode != Constants.ECONNRESET)
                 {
                     Log.RequestProcessingError(ConnectionId, ex);

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/KestrelHttpParser.cs

@@ -2,7 +2,10 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Buffers;
 using System.IO.Pipelines;
+using System.Numerics;
+using System.Runtime.CompilerServices;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.Extensions.Logging;
 
@@ -31,38 +34,36 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             consumed = buffer.Start;
             examined = buffer.End;
 
-            var start = buffer.Start;
             ReadCursor end;
-            if (ReadCursorOperations.Seek(start, buffer.End, out end, ByteLF) == -1)
-            {
-                return false;
-            }
-
-            const int stackAllocLimit = 512;
-
-            // Move 1 byte past the \n
-            end = buffer.Move(end, 1);
-            var startLineBuffer = buffer.Slice(start, end);
-
             Span<byte> span;
 
-            if (startLineBuffer.IsSingleSpan)
+            // If the buffer is a single span then use it to find the LF
+            if (buffer.IsSingleSpan)
             {
-                // No copies, directly use the one and only span
+                var startLineSpan = buffer.First.Span;
-                span = startLineBuffer.First.Span;
+                var lineIndex = startLineSpan.IndexOfVectorized(ByteLF);
-            }
+
-            else if (startLineBuffer.Length < stackAllocLimit)
+                if (lineIndex == -1)
-            {
+                {
-                // Multiple buffers and < stackAllocLimit, copy into a stack buffer
+                    return false;
-                byte* stackBuffer = stackalloc byte[startLineBuffer.Length];
+                }
-                span = new Span<byte>(stackBuffer, startLineBuffer.Length);
+
-                startLineBuffer.CopyTo(span);
+                end = buffer.Move(consumed, lineIndex + 1);
+                span = startLineSpan.Slice(0, lineIndex + 1);
             }
             else
             {
-                // We're not a single span here but we can use pooled arrays to avoid allocations in the rare case
+                var start = buffer.Start;
-                span = new Span<byte>(new byte[startLineBuffer.Length]);
+                if (ReadCursorOperations.Seek(start, buffer.End, out end, ByteLF) == -1)
-                startLineBuffer.CopyTo(span);
+                {
+                    return false;
+                }
+
+                // Move 1 byte past the \n
+                end = buffer.Move(end, 1);
+                var startLineBuffer = buffer.Slice(start, end);
+
+                span = startLineBuffer.ToSpan();
             }
 
             var pathStart = -1;
@@ -71,37 +72,33 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             var pathEnd = -1;
             var versionStart = -1;
 
-            HttpVersion httpVersion = HttpVersion.Unknown;
+            var httpVersion = HttpVersion.Unknown;
-            HttpMethod method = HttpMethod.Custom;
+            HttpMethod method;
             Span<byte> customMethod;
-            var state = StartLineState.KnownMethod;
+            var i = 0;
+            var length = span.Length;
+            var done = false;
 
-            int i;
             fixed (byte* data = &span.DangerousGetPinnableReference())
             {
-                var length = span.Length;
+                switch (StartLineState.KnownMethod)
-                for (i = 0; i < length; i++)
                 {
-                    var ch = data[i];
+                    case StartLineState.KnownMethod:
+                        if (span.GetKnownMethod(out method, out var methodLength))
+                        {
+                            // Update the index, current char, state and jump directly
+                            // to the next state
+                            i += methodLength + 1;
 
-                    switch (state)
+                            goto case StartLineState.Path;
-                    {
+                        }
-                        case StartLineState.KnownMethod:
+                        goto case StartLineState.UnknownMethod;
-                            if (span.GetKnownMethod(out method, out var methodLength))
-                            {
-                                // Update the index, current char, state and jump directly
-                                // to the next state
-                                i += methodLength + 1;
-                                ch = data[i];
-                                state = StartLineState.Path;
 
-                                goto case StartLineState.Path;
+                    case StartLineState.UnknownMethod:
-                            }
+                        for (; i < length; i++)
+                        {
+                            var ch = data[i];
 
-                            state = StartLineState.UnknownMethod;
-                            goto case StartLineState.UnknownMethod;
-
-                        case StartLineState.UnknownMethod:
                             if (ch == ByteSpace)
                             {
                                 customMethod = span.Slice(0, i);
@@ -110,16 +107,23 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                                 {
                                     RejectRequestLine(span);
                                 }
+                                // Consume space
+                                i++;
 
-                                state = StartLineState.Path;
+                                goto case StartLineState.Path;
                             }
-                            else if (!IsValidTokenChar((char)ch))
+
+                            if (!IsValidTokenChar((char)ch))
                             {
                                 RejectRequestLine(span);
                             }
+                        }
 
-                            break;
+                        break;
-                        case StartLineState.Path:
+                    case StartLineState.Path:
+                        for (; i < length; i++)
+                        {
+                            var ch = data[i];
                             if (ch == ByteSpace)
                             {
                                 pathEnd = i;
@@ -133,7 +137,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                                 // No query string found
                                 queryStart = queryEnd = i;
 
-                                state = StartLineState.KnownVersion;
+                                // Consume space
+                                i++;
+
+                                goto case StartLineState.KnownVersion;
                             }
                             else if (ch == ByteQuestionMark)
                             {
@@ -146,7 +153,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                                 }
 
                                 queryStart = i;
-                                state = StartLineState.QueryString;
+                                goto case StartLineState.QueryString;
                             }
                             else if (ch == BytePercentage)
                             {
@@ -160,35 +167,42 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                             {
                                 pathStart = i;
                             }
-                            break;
+                        }
-
+                        break;
-                        case StartLineState.QueryString:
+                    case StartLineState.QueryString:
+                        for (; i < length; i++)
+                        {
+                            var ch = data[i];
                             if (ch == ByteSpace)
                             {
                                 queryEnd = i;
-                                state = StartLineState.KnownVersion;
 
+                                // Consume space
+                                i++;
+
+                                goto case StartLineState.KnownVersion;
                             }
-                            break;
+                        }
-                        case StartLineState.KnownVersion:
+                        break;
-                            // REVIEW: We don't *need* to slice here but it makes the API
+                    case StartLineState.KnownVersion:
-                            // nicer, slicing should be free :)
+                        // REVIEW: We don't *need* to slice here but it makes the API
-                            if (span.Slice(i).GetKnownVersion(out httpVersion, out var versionLenght))
+                        // nicer, slicing should be free :)
-                            {
+                        if (span.Slice(i).GetKnownVersion(out httpVersion, out var versionLenght))
-                                // Update the index, current char, state and jump directly
+                        {
-                                // to the next state
+                            // Update the index, current char, state and jump directly
-                                i += versionLenght + 1;
+                            // to the next state
-                                ch = data[i];
+                            i += versionLenght + 1;
-                                state = StartLineState.NewLine;
+                            goto case StartLineState.NewLine;
+                        }
 
-                                goto case StartLineState.NewLine;
+                        versionStart = i;
-                            }
 
-                            versionStart = i;
+                        goto case StartLineState.UnknownVersion;
-                            state = StartLineState.UnknownVersion;
-                            goto case StartLineState.UnknownVersion;
 
-                        case StartLineState.UnknownVersion:
+                    case StartLineState.UnknownVersion:
+                        for (; i < length; i++)
+                        {
+                            var ch = data[i];
                             if (ch == ByteCR)
                             {
                                 var versionSpan = span.Slice(versionStart, i - versionStart);
@@ -199,25 +213,27 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                                 }
                                 else
                                 {
-                                    RejectRequest(RequestRejectionReason.UnrecognizedHTTPVersion, versionSpan.GetAsciiStringEscaped(32));
+                                    RejectRequest(RequestRejectionReason.UnrecognizedHTTPVersion,
+                                        versionSpan.GetAsciiStringEscaped(32));
                                 }
                             }
-                            break;
+                        }
-                        case StartLineState.NewLine:
+                        break;
-                            if (ch != ByteLF)
+                    case StartLineState.NewLine:
-                            {
+                        if (data[i] != ByteLF)
-                                RejectRequestLine(span);
+                        {
-                            }
+                            RejectRequestLine(span);
+                        }
+                        i++;
 
-                            state = StartLineState.Complete;
+                        goto case StartLineState.Complete;
-                            break;
+                    case StartLineState.Complete:
-                        case StartLineState.Complete:
+                        done = true;
-                            break;
+                        break;
-                    }
                 }
             }
 
-            if (state != StartLineState.Complete)
+            if (!done)
             {
                 RejectRequestLine(span);
             }
@@ -227,7 +243,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             var query = span.Slice(queryStart, queryEnd - queryStart);
 
             handler.OnStartLine(method, httpVersion, targetBuffer, pathBuffer, query, customMethod);
-            consumed = buffer.Move(start, i);
+
+            consumed = end;
             examined = consumed;
             return true;
         }
@@ -241,241 +258,256 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             var bufferEnd = buffer.End;
 
             var reader = new ReadableBufferReader(buffer);
-            while (true)
+            var start = default(ReadableBufferReader);
+            var done = false;
+
+            try
             {
-                var start = reader;
+                while (!reader.End)
-                int ch1 = reader.Take();
-                var ch2 = reader.Take();
-
-                if (ch1 == -1)
                 {
-                    return false;
+                    var span = reader.Span;
-                }
+                    var remaining = span.Length;
 
-                if (ch1 == ByteCR)
+                    fixed (byte* pBuffer = &span.DangerousGetPinnableReference())
-                {
-                    // Check for final CRLF.
-                    if (ch2 == -1)
                     {
-                        return false;
+                        while (remaining > 0)
-                    }
-                    else if (ch2 == ByteLF)
-                    {
-                        consumed = reader.Cursor;
-                        examined = consumed;
-                        return true;
-                    }
-
-                    // Headers don't end in CRLF line.
-                    RejectRequest(RequestRejectionReason.HeadersCorruptedInvalidHeaderSequence);
-                }
-                else if (ch1 == ByteSpace || ch1 == ByteTab)
-                {
-                    RejectRequest(RequestRejectionReason.HeaderLineMustNotStartWithWhitespace);
-                }
-
-                // Reset the reader since we're not at the end of headers
-                reader = start;
-
-                if (ReadCursorOperations.Seek(consumed, bufferEnd, out var lineEnd, ByteLF) == -1)
-                {
-                    return false;
-                }
-
-                const int stackAllocLimit = 512;
-
-                if (lineEnd != bufferEnd)
-                {
-                    lineEnd = buffer.Move(lineEnd, 1);
-                }
-
-                var headerBuffer = buffer.Slice(consumed, lineEnd);
-
-                Span<byte> span;
-                if (headerBuffer.IsSingleSpan)
-                {
-                    // No copies, directly use the one and only span
-                    span = headerBuffer.First.Span;
-                }
-                else if (headerBuffer.Length < stackAllocLimit)
-                {
-                    // Multiple buffers and < stackAllocLimit, copy into a stack buffer
-                    byte* stackBuffer = stackalloc byte[headerBuffer.Length];
-                    span = new Span<byte>(stackBuffer, headerBuffer.Length);
-                    headerBuffer.CopyTo(span);
-                }
-                else
-                {
-                    // We're not a single span here but we can use pooled arrays to avoid allocations in the rare case
-                    span = new Span<byte>(new byte[headerBuffer.Length]);
-                    headerBuffer.CopyTo(span);
-                }
-
-                var state = HeaderState.Name;
-                var nameStart = 0;
-                var nameEnd = -1;
-                var valueStart = -1;
-                var valueEnd = -1;
-                var nameHasWhitespace = false;
-                var previouslyWhitespace = false;
-                var headerLineLength = span.Length;
-
-                fixed (byte* data = &span.DangerousGetPinnableReference())
-                {
-                    for (var i = 0; i < headerLineLength; i++)
-                    {
-                        var ch = data[i];
-
-                        switch (state)
                         {
-                            case HeaderState.Name:
+                            var index = reader.Index;
-                                if (ch == ByteColon)
+                            int ch1;
-                                {
+                            int ch2;
-                                    if (nameHasWhitespace)
-                                    {
-                                        RejectRequest(RequestRejectionReason.WhitespaceIsNotAllowedInHeaderName);
-                                    }
 
-                                    state = HeaderState.Whitespace;
+                            // Fast path, we're still looking at the same span
-                                    nameEnd = i;
+                            if (remaining >= 2)
-                                }
-
-                                if (ch == ByteSpace || ch == ByteTab)
-                                {
-                                    nameHasWhitespace = true;
-                                }
-                                break;
-                            case HeaderState.Whitespace:
                             {
-                                var whitespace = ch == ByteTab || ch == ByteSpace || ch == ByteCR;
+                                ch1 = pBuffer[index];
-
+                                ch2 = pBuffer[index + 1];
-                                if (!whitespace)
-                                {
-                                    // Mark the first non whitespace char as the start of the
-                                    // header value and change the state to expect to the header value
-                                    valueStart = i;
-                                    state = HeaderState.ExpectValue;
-                                }
-                                // If we see a CR then jump to the next state directly
-                                else if (ch == ByteCR)
-                                {
-                                    state = HeaderState.ExpectValue;
-                                    goto case HeaderState.ExpectValue;
-                                }
                             }
-                                break;
+                            else
-                            case HeaderState.ExpectValue:
                             {
-                                var whitespace = ch == ByteTab || ch == ByteSpace;
+                                // Store the reader before we look ahead 2 bytes (probably straddling
+                                // spans)
+                                start = reader;
 
-                                if (whitespace)
+                                // Possibly split across spans
-                                {
+                                ch1 = reader.Take();
-                                    if (!previouslyWhitespace)
+                                ch2 = reader.Take();
-                                    {
-                                        // If we see a whitespace char then maybe it's end of the
-                                        // header value
-                                        valueEnd = i;
-                                    }
-                                }
-                                else if (ch == ByteCR)
-                                {
-                                    // If we see a CR and we haven't ever seen whitespace then
-                                    // this is the end of the header value
-                                    if (valueEnd == -1)
-                                    {
-                                        valueEnd = i;
-                                    }
-
-                                    // We never saw a non whitespace character before the CR
-                                    if (valueStart == -1)
-                                    {
-                                        valueStart = valueEnd;
-                                    }
-
-                                    state = HeaderState.ExpectNewLine;
-                                }
-                                else
-                                {
-                                    // If we find a non whitespace char that isn't CR then reset the end index
-                                    valueEnd = -1;
-                                }
-
-                                previouslyWhitespace = whitespace;
                             }
-                                break;
+
-                            case HeaderState.ExpectNewLine:
+                            if (ch1 == ByteCR)
-                                if (ch != ByteLF)
+                            {
+                                // Check for final CRLF.
+                                if (ch2 == -1)
                                 {
-                                    RejectRequest(RequestRejectionReason.HeaderValueMustNotContainCR);
+                                    // Reset the reader so we don't consume anything
+                                    reader = start;
+                                    return false;
+                                }
+                                else if (ch2 == ByteLF)
+                                {
+                                    // If we got 2 bytes from the span directly so skip ahead 2 so that
+                                    // the reader's state matches what we expect
+                                    if (index == reader.Index)
+                                    {
+                                        reader.Skip(2);
+                                    }
+
+                                    done = true;
+                                    return true;
                                 }
 
-                                state = HeaderState.Complete;
+                                // Headers don't end in CRLF line.
-                                break;
+                                RejectRequest(RequestRejectionReason.HeadersCorruptedInvalidHeaderSequence);
-                            default:
+                            }
-                                break;
+                            else if(ch1 == ByteSpace || ch1 == ByteTab)
+                            {
+                                RejectRequest(RequestRejectionReason.WhitespaceIsNotAllowedInHeaderName);
+                            }
+
+                            // We moved the reader so look ahead 2 bytes so reset both the reader
+                            // and the index
+                            if (index != reader.Index)
+                            {
+                                reader = start;
+                                index = reader.Index;
+                            }
+
+                            var endIndex = new Span<byte>(pBuffer + index, remaining).IndexOfVectorized(ByteLF);
+                            var length = 0;
+
+                            if (endIndex != -1)
+                            {
+                                length = endIndex + 1;
+                                var pHeader = pBuffer + index;
+
+                                TakeSingleHeader(pHeader, length, handler);
+                            }
+                            else
+                            {
+                                var current = reader.Cursor;
+
+                                // Split buffers
+                                if (ReadCursorOperations.Seek(current, bufferEnd, out var lineEnd, ByteLF) == -1)
+                                {
+                                    // Not there
+                                    return false;
+                                }
+
+                                // Make sure LF is included in lineEnd
+                                lineEnd = buffer.Move(lineEnd, 1);
+                                var headerSpan = buffer.Slice(current, lineEnd).ToSpan();
+                                length = headerSpan.Length;
+
+                                fixed (byte* pHeader = &headerSpan.DangerousGetPinnableReference())
+                                {
+                                    TakeSingleHeader(pHeader, length, handler);
+                                }
+
+                                // We're going to the next span after this since we know we crossed spans here
+                                // so mark the remaining as equal to the headerSpan so that we end up at 0
+                                // on the next iteration
+                                remaining = length;
+                            }
+
+                            // Skip the reader forward past the header line
+                            reader.Skip(length);
+                            remaining -= length;
                         }
                     }
                 }
 
-                if (state == HeaderState.Name)
+                return false;
-                {
-                    RejectRequest(RequestRejectionReason.NoColonCharacterFoundInHeaderLine);
-                }
-
-                if (state == HeaderState.ExpectValue || state == HeaderState.Whitespace)
-                {
-                    RejectRequest(RequestRejectionReason.MissingCRInHeaderLine);
-                }
-
-                if (state != HeaderState.Complete)
-                {
-                    return false;
-                }
-
-                // Skip the reader forward past the header line
-                reader.Skip(headerLineLength);
-
-                // Before accepting the header line, we need to see at least one character
-                // > so we can make sure there's no space or tab
-                var next = reader.Peek();
-
-                // TODO: We don't need to reject the line here, we can use the state machine
-                // to store the fact that we're reading a header value
-                if (next == -1)
-                {
-                    // If we can't see the next char then reject the entire line
-                    return false;
-                }
-
-                if (next == ByteSpace || next == ByteTab)
-                {
-                    // From https://tools.ietf.org/html/rfc7230#section-3.2.4:
-                    //
-                    // Historically, HTTP header field values could be extended over
-                    // multiple lines by preceding each extra line with at least one space
-                    // or horizontal tab (obs-fold).  This specification deprecates such
-                    // line folding except within the message/http media type
-                    // (Section 8.3.1).  A sender MUST NOT generate a message that includes
-                    // line folding (i.e., that has any field-value that contains a match to
-                    // the obs-fold rule) unless the message is intended for packaging
-                    // within the message/http media type.
-                    //
-                    // A server that receives an obs-fold in a request message that is not
-                    // within a message/http container MUST either reject the message by
-                    // sending a 400 (Bad Request), preferably with a representation
-                    // explaining that obsolete line folding is unacceptable, or replace
-                    // each received obs-fold with one or more SP octets prior to
-                    // interpreting the field value or forwarding the message downstream.
-                    RejectRequest(RequestRejectionReason.HeaderValueLineFoldingNotSupported);
-                }
-
-                var nameBuffer = span.Slice(nameStart, nameEnd - nameStart);
-                var valueBuffer = span.Slice(valueStart, valueEnd - valueStart);
-                consumedBytes += headerLineLength;
-
-                handler.OnHeader(nameBuffer, valueBuffer);
-                consumed = reader.Cursor;
             }
+            finally
+            {
+                consumed = reader.Cursor;
+                consumedBytes = reader.ConsumedBytes;
+
+                if (done)
+                {
+                    examined = consumed;
+                }
+            }
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private static unsafe int FindEndOfName(byte* headerLine, int length)
+        {
+            var index = 0;
+            var sawWhitespace = false;
+            for (; index < length; index++)
+            {
+                var ch = headerLine[index];
+                if (ch == ByteColon)
+                {
+                    break;
+                }
+                if (ch == ByteTab || ch == ByteSpace || ch == ByteCR)
+                {
+                    sawWhitespace = true;
+                }
+            }
+
+            if (index == length)
+            {
+                RejectRequest(RequestRejectionReason.NoColonCharacterFoundInHeaderLine);
+            }
+            if (sawWhitespace)
+            {
+                RejectRequest(RequestRejectionReason.WhitespaceIsNotAllowedInHeaderName);
+            }
+            return index;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private unsafe void TakeSingleHeader<T>(byte* headerLine, int length, T handler) where T : IHttpHeadersHandler
+        {
+            // Skip CR, LF from end position
+            var valueEnd = length - 3;
+            var nameEnd = FindEndOfName(headerLine, length);
+
+            if (headerLine[valueEnd + 2] != ByteLF)
+            {
+                RejectRequest(RequestRejectionReason.HeaderValueMustNotContainCR);
+            }
+            if (headerLine[valueEnd + 1] != ByteCR)
+            {
+                RejectRequest(RequestRejectionReason.MissingCRInHeaderLine);
+            }
+
+            // Skip colon from value start
+            var valueStart = nameEnd + 1;
+            // Ignore start whitespace
+            for(; valueStart < valueEnd; valueStart++)
+            {
+                var ch = headerLine[valueStart];
+                if (ch != ByteTab && ch != ByteSpace && ch != ByteCR)
+                {
+                    break;
+                }
+                else if (ch == ByteCR)
+                {
+                    RejectRequest(RequestRejectionReason.HeaderValueMustNotContainCR);
+                }
+            }
+
+
+            // Check for CR in value
+            var i = valueStart + 1;
+            if (Contains(headerLine + i, valueEnd - i, ByteCR))
+            {
+                RejectRequest(RequestRejectionReason.HeaderValueMustNotContainCR);
+            }
+
+            // Ignore end whitespace
+            for (; valueEnd >= valueStart; valueEnd--)
+            {
+                var ch = headerLine[valueEnd];
+                if (ch != ByteTab && ch != ByteSpace)
+                {
+                    break;
+                }
+            }
+
+            var nameBuffer = new Span<byte>(headerLine, nameEnd);
+            var valueBuffer = new Span<byte>(headerLine + valueStart, valueEnd - valueStart + 1);
+
+            handler.OnHeader(nameBuffer, valueBuffer);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private static unsafe bool Contains(byte* searchSpace, int length, byte value)
+        {
+            var i = 0;
+            if (Vector.IsHardwareAccelerated)
+            {
+                // Check Vector lengths
+                if (length - Vector<byte>.Count >= i)
+                {
+                    var vValue = GetVector(value);
+                    do
+                    {
+                        if (!Vector<byte>.Zero.Equals(Vector.Equals(vValue, Unsafe.Read<Vector<byte>>(searchSpace + i))))
+                        {
+                            goto found;
+                        }
+
+                        i += Vector<byte>.Count;
+                    } while (length - Vector<byte>.Count >= i);
+                }
+            }
+
+            // Check remaining for CR
+            for (; i <= length; i++)
+            {
+                var ch = searchSpace[i];
+                if (ch == value)
+                {
+                    goto found;
+                }
+            }
+            return false;
+        found:
+            return true;
         }
 
         private static bool IsValidTokenChar(char c)
@@ -503,31 +535,40 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
                 c == '~';
         }
 
-        public void RejectRequest(RequestRejectionReason reason)
+        public static void RejectRequest(RequestRejectionReason reason)
         {
-            RejectRequest(BadHttpRequestException.GetException(reason));
+            throw BadHttpRequestException.GetException(reason);
         }
 
-        public void RejectRequest(RequestRejectionReason reason, string value)
+        public static void RejectRequest(RequestRejectionReason reason, string value)
         {
-            RejectRequest(BadHttpRequestException.GetException(reason, value));
+            throw BadHttpRequestException.GetException(reason, value);
-        }
-
-        private void RejectRequest(BadHttpRequestException ex)
-        {
-            throw ex;
         }
 
         private void RejectRequestLine(Span<byte> span)
+        {
+            throw GetRejectRequestLineException(span);
+        }
+
+        private BadHttpRequestException GetRejectRequestLineException(Span<byte> span)
         {
             const int MaxRequestLineError = 32;
-            RejectRequest(RequestRejectionReason.InvalidRequestLine,
+            return BadHttpRequestException.GetException(RequestRejectionReason.InvalidRequestLine,
                 Log.IsEnabled(LogLevel.Information) ? span.GetAsciiStringEscaped(MaxRequestLineError) : string.Empty);
         }
 
         public void Reset()
         {
-            
+
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static Vector<byte> GetVector(byte vectorByte)
+        {
+            // Vector<byte> .ctor doesn't become an intrinsic due to detection issue
+            // However this does cause it to become an intrinsic (with additional multiply and reg->reg copy)
+            // https://github.com/dotnet/coreclr/issues/7459#issuecomment-253965670
+            return Vector.AsVectorByte(new Vector<uint>(vectorByte * 0x01010101u));
         }
 
         private enum HeaderState
@@ -551,4 +592,4 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             Complete
         }
     }
-}
+}

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/MessageBody.cs

@@ -595,7 +595,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 
                         try
                         {
-                            if (_context.TakeMessageHeaders(buffer, _requestHeaders, out consumed, out examined))
+                            if (_context.TakeMessageHeaders(buffer, out consumed, out examined))
                             {
                                 break;
                             }

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/PipelineExtensions.cs

@@ -3,9 +3,8 @@
 
 using System;
 using System.IO.Pipelines;
-using System.Threading;
+using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
 {
@@ -47,8 +46,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             {
                 var result = await readingTask;
 
-                await AwaitableThreadPool.Yield();
-
                 try
                 {
                     if (!result.Buffer.IsEmpty)
@@ -70,13 +67,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             }
         }
 
-        private static async Task<ReadResult> ReadAsyncDispatchedAwaited(ReadableBufferAwaitable awaitable)
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        {
-            var result = await awaitable;
-            await AwaitableThreadPool.Yield();
-            return result;
-        }
-
         public static Span<byte> ToSpan(this ReadableBuffer buffer)
         {
             if (buffer.IsSingleSpan)
@@ -86,15 +77,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
             return buffer.ToArray();
         }
 
-        public static ArraySegment<byte> ToArraySegment(this ReadableBuffer buffer)
-        {
-            if (buffer.IsSingleSpan)
-            {
-                return buffer.First.GetArray();
-            }
-            return new ArraySegment<byte>(buffer.ToArray());
-        }
-
         public static ArraySegment<byte> GetArray(this Memory<byte> memory)
         {
             ArraySegment<byte> result;

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/RequestProcessingStatus.cs

@@ -0,0 +1,14 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
+{
+    public enum RequestProcessingStatus
+    {
+        RequestPending,
+        ParsingRequestLine,
+        ParsingHeaders,
+        AppStarted,
+        ResponseStarted
+    }
+}

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/RequestRejectionReason.cs

@@ -7,7 +7,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
     {
         UnrecognizedHTTPVersion,
         HeadersCorruptedInvalidHeaderSequence,
-        HeaderLineMustNotStartWithWhitespace,
         NoColonCharacterFoundInHeaderLine,
         WhitespaceIsNotAllowedInHeaderName,
         HeaderValueMustNotContainCR,

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/UrlPathDecoder.cs

@@ -1,312 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
-
-namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Http
-{
-    public class UrlPathDecoder
-    {
-        /// <summary>
-        /// Unescapes the string between given memory iterators in place.
-        /// </summary>
-        /// <param name="start">The iterator points to the beginning of the sequence.</param>
-        /// <param name="end">The iterator points to the byte behind the end of the sequence.</param>
-        /// <returns>The iterator points to the byte behind the end of the processed sequence.</returns>
-        public static MemoryPoolIterator Unescape(MemoryPoolIterator start, MemoryPoolIterator end)
-        {
-            // the slot to read the input
-            var reader = start;
-
-            // the slot to write the unescaped byte
-            var writer = reader;
-
-            while (true)
-            {
-                if (CompareIterators(ref reader, ref end))
-                {
-                    return writer;
-                }
-
-                if (reader.Peek() == '%')
-                {
-                    var decodeReader = reader;
-
-                    // If decoding process succeeds, the writer iterator will be moved
-                    // to the next write-ready location. On the other hand if the scanned
-                    // percent-encodings cannot be interpreted as sequence of UTF-8 octets,
-                    // these bytes should be copied to output as is. 
-                    // The decodeReader iterator is always moved to the first byte not yet 
-                    // be scanned after the process. A failed decoding means the chars
-                    // between the reader and decodeReader can be copied to output untouched. 
-                    if (!DecodeCore(ref decodeReader, ref writer, end))
-                    {
-                        Copy(reader, decodeReader, ref writer);
-                    }
-
-                    reader = decodeReader;
-                }
-                else
-                {
-                    writer.Put((byte)reader.Take());
-                }
-            }
-        }
-
-        /// <summary>
-        /// Unescape the percent-encodings
-        /// </summary>
-        /// <param name="reader">The iterator point to the first % char</param>
-        /// <param name="writer">The place to write to</param>
-        /// <param name="end">The end of the sequence</param>
-        private static bool DecodeCore(ref MemoryPoolIterator reader, ref MemoryPoolIterator writer, MemoryPoolIterator end)
-        {
-            // preserves the original head. if the percent-encodings cannot be interpreted as sequence of UTF-8 octets,
-            // bytes from this till the last scanned one will be copied to the memory pointed by writer.
-            var byte1 = UnescapePercentEncoding(ref reader, end);
-
-            if (byte1 == 0)
-            {
-                throw BadHttpRequestException.GetException(RequestRejectionReason.PathContainsNullCharacters);
-            }
-
-            if (byte1 == -1)
-            {
-                return false;
-            }
-
-            if (byte1 <= 0x7F)
-            {
-                // first byte < U+007f, it is a single byte ASCII
-                writer.Put((byte)byte1);
-                return true;
-            }
-
-            int byte2 = 0, byte3 = 0, byte4 = 0;
-
-            // anticipate more bytes
-            var currentDecodeBits = 0;
-            var byteCount = 1;
-            var expectValueMin = 0;
-            if ((byte1 & 0xE0) == 0xC0)
-            {
-                // 110x xxxx, expect one more byte
-                currentDecodeBits = byte1 & 0x1F;
-                byteCount = 2;
-                expectValueMin = 0x80;
-            }
-            else if ((byte1 & 0xF0) == 0xE0)
-            {
-                // 1110 xxxx, expect two more bytes
-                currentDecodeBits = byte1 & 0x0F;
-                byteCount = 3;
-                expectValueMin = 0x800;
-            }
-            else if ((byte1 & 0xF8) == 0xF0)
-            {
-                // 1111 0xxx, expect three more bytes
-                currentDecodeBits = byte1 & 0x07;
-                byteCount = 4;
-                expectValueMin = 0x10000;
-            }
-            else
-            {
-                // invalid first byte
-                return false;
-            }
-
-            var remainingBytes = byteCount - 1;
-            while (remainingBytes > 0)
-            {
-                // read following three chars
-                if (CompareIterators(ref reader, ref end))
-                {
-                    return false;
-                }
-
-                var nextItr = reader;
-                var nextByte = UnescapePercentEncoding(ref nextItr, end);
-                if (nextByte == -1)
-                {
-                    return false;
-                }
-
-                if ((nextByte & 0xC0) != 0x80)
-                {
-                    // the follow up byte is not in form of 10xx xxxx
-                    return false;
-                }
-
-                currentDecodeBits = (currentDecodeBits << 6) | (nextByte & 0x3F);
-                remainingBytes--;
-
-                if (remainingBytes == 1 && currentDecodeBits >= 0x360 && currentDecodeBits <= 0x37F)
-                {
-                    // this is going to end up in the range of 0xD800-0xDFFF UTF-16 surrogates that
-                    // are not allowed in UTF-8;
-                    return false;
-                }
-
-                if (remainingBytes == 2 && currentDecodeBits >= 0x110)
-                {
-                    // this is going to be out of the upper Unicode bound 0x10FFFF.
-                    return false;
-                }
-
-                reader = nextItr;
-                if (byteCount - remainingBytes == 2)
-                {
-                    byte2 = nextByte;
-                }
-                else if (byteCount - remainingBytes == 3)
-                {
-                    byte3 = nextByte;
-                }
-                else if (byteCount - remainingBytes == 4)
-                {
-                    byte4 = nextByte;
-                }
-            }
-
-            if (currentDecodeBits < expectValueMin)
-            {
-                // overlong encoding (e.g. using 2 bytes to encode something that only needed 1).
-                return false;
-            }
-
-            // all bytes are verified, write to the output
-            if (byteCount > 0)
-            {
-                writer.Put((byte)byte1);
-            }
-            if (byteCount > 1)
-            {
-                writer.Put((byte)byte2);
-            }
-            if (byteCount > 2)
-            {
-                writer.Put((byte)byte3);
-            }
-            if (byteCount > 3)
-            {
-                writer.Put((byte)byte4);
-            }
-
-            return true;
-        }
-
-        private static void Copy(MemoryPoolIterator head, MemoryPoolIterator tail, ref MemoryPoolIterator writer)
-        {
-            while (!CompareIterators(ref head, ref tail))
-            {
-                writer.Put((byte)head.Take());
-            }
-        }
-
-        /// <summary>
-        /// Read the percent-encoding and try unescape it.
-        /// 
-        /// The operation first peek at the character the <paramref name="scan"/> 
-        /// iterator points at. If it is % the <paramref name="scan"/> is then 
-        /// moved on to scan the following to characters. If the two following 
-        /// characters are hexadecimal literals they will be unescaped and the 
-        /// value will be returned.
-        /// 
-        /// If the first character is not % the <paramref name="scan"/> iterator 
-        /// will be removed beyond the location of % and -1 will be returned.
-        /// 
-        /// If the following two characters can't be successfully unescaped the 
-        /// <paramref name="scan"/> iterator will be move behind the % and -1 
-        /// will be returned.
-        /// </summary>
-        /// <param name="scan">The value to read</param>
-        /// <param name="end">The end of the sequence</param>
-        /// <returns>The unescaped byte if success. Otherwise return -1.</returns>
-        private static int UnescapePercentEncoding(ref MemoryPoolIterator scan, MemoryPoolIterator end)
-        {
-            if (scan.Take() != '%')
-            {
-                return -1;
-            }
-
-            var probe = scan;
-
-            int value1 = ReadHex(ref probe, end);
-            if (value1 == -1)
-            {
-                return -1;
-            }
-
-            int value2 = ReadHex(ref probe, end);
-            if (value2 == -1)
-            {
-                return -1;
-            }
-
-            if (SkipUnescape(value1, value2))
-            {
-                return -1;
-            }
-
-            scan = probe;
-            return (value1 << 4) + value2;
-        }
-
-        /// <summary>
-        /// Read the next char and convert it into hexadecimal value.
-        /// 
-        /// The <paramref name="scan"/> iterator will be moved to the next
-        /// byte no matter no matter whether the operation successes.
-        /// </summary>
-        /// <param name="scan">The value to read</param>
-        /// <param name="end">The end of the sequence</param>
-        /// <returns>The hexadecimal value if successes, otherwise -1.</returns>
-        private static int ReadHex(ref MemoryPoolIterator scan, MemoryPoolIterator end)
-        {
-            if (CompareIterators(ref scan, ref end))
-            {
-                return -1;
-            }
-
-            var value = scan.Take();
-            var isHead = (((value >= '0') && (value <= '9')) ||
-                          ((value >= 'A') && (value <= 'F')) ||
-                          ((value >= 'a') && (value <= 'f')));
-
-            if (!isHead)
-            {
-                return -1;
-            }
-
-            if (value <= '9')
-            {
-                return value - '0';
-            }
-            else if (value <= 'F')
-            {
-                return (value - 'A') + 10;
-            }
-            else // a - f
-            {
-                return (value - 'a') + 10;
-            }
-        }
-
-        private static bool SkipUnescape(int value1, int value2)
-        {
-            // skip %2F
-            if (value1 == 2 && value2 == 15)
-            {
-                return true;
-            }
-
-            return false;
-        }
-
-        private static bool CompareIterators(ref MemoryPoolIterator lhs, ref MemoryPoolIterator rhs)
-        {
-            // uses ref parameter to save cost of copying
-            return (lhs.Block == rhs.Block) && (lhs.Index == rhs.Index);
-        }
-    }
-}

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/AwaitableThreadPool.cs

@@ -1,39 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Runtime.CompilerServices;
-using System.Threading.Tasks;
-
-namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
-{
-    internal static class AwaitableThreadPool
-    {
-        internal static Awaitable Yield()
-        {
-            return new Awaitable();
-        }
-
-        internal struct Awaitable : ICriticalNotifyCompletion
-        {
-            public void GetResult()
-            {
-
-            }
-
-            public Awaitable GetAwaiter() => this;
-
-            public bool IsCompleted => false;
-
-            public void OnCompleted(Action continuation)
-            {
-                Task.Run(continuation);
-            }
-
-            public void UnsafeOnCompleted(Action continuation)
-            {
-                OnCompleted(continuation);
-            }
-        }
-    }
-}

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/Constants.cs

@@ -17,7 +17,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
         /// <summary>
         /// The IPEndPoint Kestrel will bind to if nothing else is specified.
         /// </summary>
-        public static readonly IPEndPoint DefaultIPEndPoint = new IPEndPoint(IPAddress.Loopback, 5000);
+        public static readonly string DefaultServerAddress = "http://localhost:5000";
 
         /// <summary>
         /// Prefix of host name used to specify Unix sockets in the configuration.

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/HttpUtilities.cs

@@ -124,6 +124,28 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
             }
         }
 
+        public unsafe static string GetAsciiStringNonNullCharacters(this Span<byte> span)
+        {
+            if (span.IsEmpty)
+            {
+                return string.Empty;
+            }
+
+            var asciiString = new string('\0', span.Length);
+
+            fixed (char* output = asciiString)
+            fixed (byte* buffer = &span.DangerousGetPinnableReference())
+            {
+                // This version if AsciiUtilities returns null if there are any null (0 byte) characters
+                // in the string
+                if (!AsciiUtilities.TryGetAsciiString(buffer, output, span.Length))
+                {
+                    throw new InvalidOperationException();
+                }
+            }
+            return asciiString;
+        }
+
         public static string GetAsciiStringEscaped(this Span<byte> span, int maxChars)
         {
             var sb = new StringBuilder();

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Infrastructure/MemoryPoolIterator.cs

@@ -14,15 +14,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
     public struct MemoryPoolIterator
     {
         private const int _maxULongByteLength = 20;
-        private const ulong _xorPowerOfTwoToHighByte = (0x07ul       |
-                                                        0x06ul <<  8 |
-                                                        0x05ul << 16 |
-                                                        0x04ul << 24 |
-                                                        0x03ul << 32 |
-                                                        0x02ul << 40 |
-                                                        0x01ul << 48 ) + 1;
-
-        private static readonly int _vectorSpan = Vector<byte>.Count;
 
         [ThreadStatic]
         private static byte[] _numericBytesScratch;
@@ -135,668 +126,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
                 }
             } while (true);
         }
-
+        
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public void Skip(int bytesToSkip)
-        {
-            var block = _block;
-            if (block == null && bytesToSkip > 0)
-            {
-                ThrowInvalidOperationException_SkipMoreThanAvailable();
-            }
-
-            // Always set wasLastBlock before checking .End to avoid race which may cause data loss
-            var wasLastBlock = block.Next == null;
-            var following = block.End - _index;
-
-            if (following >= bytesToSkip)
-            {
-                _index += bytesToSkip;
-                return;
-            }
-
-            if (wasLastBlock)
-            {
-                ThrowInvalidOperationException_SkipMoreThanAvailable();
-            }
-
-            SkipMultiBlock(bytesToSkip, following);
-        }
-
-        [MethodImpl(MethodImplOptions.NoInlining)]
-        private void SkipMultiBlock(int bytesToSkip, int following)
-        {
-            var block = _block;
-            do
-            {
-                bytesToSkip -= following;
-                block = block.Next;
-                var index = block.Start;
-
-                // Always set wasLastBlock before checking .End to avoid race which may cause data loss
-                var wasLastBlock = block.Next == null;
-                following = block.End - index;
-
-                if (following >= bytesToSkip)
-                {
-                    _block = block;
-                    _index = index + bytesToSkip;
-                    return;
-                }
-
-                if (wasLastBlock)
-                {
-                    ThrowInvalidOperationException_SkipMoreThanAvailable();
-                }
-            } while (true);
-        }
-
-        private static void ThrowInvalidOperationException_SkipMoreThanAvailable()
-        {
-            throw new InvalidOperationException("Attempted to skip more bytes than available.");
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public int Peek()
-        {
-            var block = _block;
-            if (block == null)
-            {
-                return -1;
-            }
-
-            var index = _index;
-
-            // Always set wasLastBlock before checking .End to avoid race which may cause data loss
-            var wasLastBlock = block.Next == null;
-            if (index < block.End)
-            {
-                return block.Array[index];
-            }
-
-            return wasLastBlock ? -1 : PeekMultiBlock();
-        }
-
-        [MethodImpl(MethodImplOptions.NoInlining)]
-        private int PeekMultiBlock()
-        {
-            var block = _block;
-            do
-            {
-                block = block.Next;
-                var index = block.Start;
-
-                // Always set wasLastBlock before checking .End to avoid race which may cause data loss 
-                var wasLastBlock = block.Next == null;
-
-                if (index < block.End)
-                {
-                    return block.Array[index];
-                }
-                if (wasLastBlock)
-                {
-                    return -1;
-                }
-            } while (true);
-        }
-
-        // NOTE: Little-endian only!
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public unsafe bool TryPeekLong(out ulong longValue)
-        {
-            longValue = 0;
-
-            var block = _block;
-            if (block == null)
-            {
-                return false;
-            }
-
-            // Always set wasLastBlock before checking .End to avoid race which may cause data loss 
-            var wasLastBlock = block.Next == null;
-            var blockBytes = block.End - _index;
-
-            if (blockBytes >= sizeof(ulong))
-            {
-                longValue = *(ulong*)(block.DataFixedPtr + _index);
-                return true;
-            }
-
-            return wasLastBlock ? false : TryPeekLongMultiBlock(ref longValue, blockBytes);
-        }
-
-        [MethodImpl(MethodImplOptions.NoInlining)]
-        private unsafe bool TryPeekLongMultiBlock(ref ulong longValue, int blockBytes)
-        {
-            // Each block will be filled with at least 2048 bytes before the Next pointer is set, so a long
-            // will cross at most one block boundary assuming there are at least 8 bytes following the iterator.
-            var nextBytes = sizeof(ulong) - blockBytes;
-
-            var block = _block;
-            if (block.Next.End - block.Next.Start < nextBytes)
-            {
-                return false;
-            }
-
-            var nextLong = *(ulong*)(block.Next.DataFixedPtr + block.Next.Start);
-
-            if (blockBytes == 0)
-            {
-                // This case can not fall through to the else block since that would cause a 64-bit right shift
-                // on blockLong which is equivalent to no shift at all instead of shifting in all zeros.
-                // https://msdn.microsoft.com/en-us/library/xt18et0d.aspx
-                longValue = nextLong;
-            }
-            else
-            {
-                var blockLong = *(ulong*)(block.DataFixedPtr + block.End - sizeof(ulong));
-
-                // Ensure that the right shift has a ulong operand so a logical shift is performed.
-                longValue = (blockLong >> nextBytes * 8) | (nextLong << blockBytes * 8);
-            }
-
-            return true;
-        }
-
-        public int Seek(byte byte0)
-        {
-            int bytesScanned;
-            return Seek(byte0, out bytesScanned);
-        }
-
-        public unsafe int Seek(
-            byte byte0,
-            out int bytesScanned,
-            int limit = int.MaxValue)
-        {
-            bytesScanned = 0;
-
-            var block = _block;
-            if (block == null || limit <= 0)
-            {
-                return -1;
-            }
-
-            var index = _index;
-            var wasLastBlock = block.Next == null;
-            var following = block.End - index;
-            byte[] array;
-            var byte0Vector = GetVector(byte0);
-
-            while (true)
-            {
-                while (following == 0)
-                {
-                    if (bytesScanned >= limit || wasLastBlock)
-                    {
-                        _block = block;
-                        _index = index;
-                        return -1;
-                    }
-
-                    block = block.Next;
-                    index = block.Start;
-                    wasLastBlock = block.Next == null;
-                    following = block.End - index;
-                }
-                array = block.Array;
-                while (following > 0)
-                {
-                    // Need unit tests to test Vector path
-#if !DEBUG
-                    // Check will be Jitted away https://github.com/dotnet/coreclr/issues/1079
-                    if (Vector.IsHardwareAccelerated)
-                    {
-#endif
-                    if (following >= _vectorSpan)
-                    {
-                        var byte0Equals = Vector.Equals(new Vector<byte>(array, index), byte0Vector);
-
-                        if (byte0Equals.Equals(Vector<byte>.Zero))
-                        {
-                            if (bytesScanned + _vectorSpan >= limit)
-                            {
-                                _block = block;
-                                // Ensure iterator is left at limit position
-                                _index = index + (limit - bytesScanned);
-                                bytesScanned = limit;
-                                return -1;
-                            }
-
-                            bytesScanned += _vectorSpan;
-                            following -= _vectorSpan;
-                            index += _vectorSpan;
-                            continue;
-                        }
-
-                        _block = block;
-
-                        var firstEqualByteIndex = LocateFirstFoundByte(byte0Equals);
-                        var vectorBytesScanned = firstEqualByteIndex + 1;
-
-                        if (bytesScanned + vectorBytesScanned > limit)
-                        {
-                            // Ensure iterator is left at limit position
-                            _index = index + (limit - bytesScanned);
-                            bytesScanned = limit;
-                            return -1;
-                        }
-
-                        _index = index + firstEqualByteIndex;
-                        bytesScanned += vectorBytesScanned;
-
-                        return byte0;
-                    }
-                    // Need unit tests to test Vector path
-#if !DEBUG
-                    }
-#endif
-
-                    var pCurrent = (block.DataFixedPtr + index);
-                    var pEnd = pCurrent + Math.Min(following, limit - bytesScanned);
-                    do
-                    {
-                        bytesScanned++;
-                        if (*pCurrent == byte0)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte0;
-                        }
-                        pCurrent++;
-                        index++;
-                    } while (pCurrent < pEnd);
-
-                    following = 0;
-                    break;
-                }
-            }
-        }
-
-        public unsafe int Seek(
-            byte byte0,
-            ref MemoryPoolIterator limit)
-        {
-            var block = _block;
-            if (block == null)
-            {
-                return -1;
-            }
-
-            var index = _index;
-            var wasLastBlock = block.Next == null;
-            var following = block.End - index;
-
-            while (true)
-            {
-                while (following == 0)
-                {
-                    if ((block == limit.Block && index > limit.Index) ||
-                        wasLastBlock)
-                    {
-                        _block = block;
-                        // Ensure iterator is left at limit position
-                        _index = limit.Index;
-                        return -1;
-                    }
-
-                    block = block.Next;
-                    index = block.Start;
-                    wasLastBlock = block.Next == null;
-                    following = block.End - index;
-                }
-                var array = block.Array;
-                while (following > 0)
-                {
-// Need unit tests to test Vector path
-#if !DEBUG
-                    // Check will be Jitted away https://github.com/dotnet/coreclr/issues/1079
-                    if (Vector.IsHardwareAccelerated)
-                    {
-#endif
-                        if (following >= _vectorSpan)
-                        {
-                            var byte0Equals = Vector.Equals(new Vector<byte>(array, index), GetVector(byte0));
-
-                            if (byte0Equals.Equals(Vector<byte>.Zero))
-                            {
-                                if (block == limit.Block && index + _vectorSpan > limit.Index)
-                                {
-                                    _block = block;
-                                    // Ensure iterator is left at limit position
-                                    _index = limit.Index;
-                                    return -1;
-                                }
-
-                                following -= _vectorSpan;
-                                index += _vectorSpan;
-                                continue;
-                            }
-
-                            _block = block;
-
-                            var firstEqualByteIndex = LocateFirstFoundByte(byte0Equals);
-
-                            if (_block == limit.Block && index + firstEqualByteIndex > limit.Index)
-                            {
-                                // Ensure iterator is left at limit position
-                                _index = limit.Index;
-                                return -1;
-                            }
-
-                            _index = index + firstEqualByteIndex;
-
-                            return byte0;
-                        }
-// Need unit tests to test Vector path
-#if !DEBUG
-                    }
-#endif
-
-                    var pCurrent = (block.DataFixedPtr + index);
-                    var pEnd = block == limit.Block ? block.DataFixedPtr + limit.Index + 1 : pCurrent + following;
-                    do
-                    {
-                        if (*pCurrent == byte0)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte0;
-                        }
-                        pCurrent++;
-                        index++;
-                    } while (pCurrent < pEnd);
-
-                    following = 0;
-                    break;
-                }
-            }
-        }
-
-        public int Seek(byte byte0, byte byte1)
-        {
-            var limit = new MemoryPoolIterator();
-            return Seek(byte0, byte1, ref limit);
-        }
-
-        public unsafe int Seek(
-            byte byte0,
-            byte byte1,
-            ref MemoryPoolIterator limit)
-        {
-            var block = _block;
-            if (block == null)
-            {
-                return -1;
-            }
-
-            var index = _index;
-            var wasLastBlock = block.Next == null;
-            var following = block.End - index;
-            int byteIndex = int.MaxValue;
-
-            while (true)
-            {
-                while (following == 0)
-                {
-                    if ((block == limit.Block && index > limit.Index) ||
-                        wasLastBlock)
-                    {
-                        _block = block;
-                        // Ensure iterator is left at limit position
-                        _index = limit.Index;
-                        return -1;
-                    }
-                    block = block.Next;
-                    index = block.Start;
-                    wasLastBlock = block.Next == null;
-                    following = block.End - index;
-                }
-                var array = block.Array;
-                while (following > 0)
-                {
-
-// Need unit tests to test Vector path
-#if !DEBUG
-                    // Check will be Jitted away https://github.com/dotnet/coreclr/issues/1079
-                    if (Vector.IsHardwareAccelerated)
-                    {
-#endif
-                        if (following >= _vectorSpan)
-                        {
-                            var data = new Vector<byte>(array, index);
-
-                            var byteEquals = Vector.Equals(data, GetVector(byte0));
-                            byteEquals = Vector.ConditionalSelect(byteEquals, byteEquals, Vector.Equals(data, GetVector(byte1)));
-
-                            if (!byteEquals.Equals(Vector<byte>.Zero))
-                            {
-                                byteIndex = LocateFirstFoundByte(byteEquals);
-                            }
-
-                            if (byteIndex == int.MaxValue)
-                            {
-                                following -= _vectorSpan;
-                                index += _vectorSpan;
-
-                                if (block == limit.Block && index > limit.Index)
-                                {
-                                    _block = block;
-                                    // Ensure iterator is left at limit position
-                                    _index = limit.Index;
-                                    return -1;
-                                }
-
-                                continue;
-                            }
-
-                            _block = block;
-
-                            _index = index + byteIndex;
-
-                            if (block == limit.Block && _index > limit.Index)
-                            {
-                                // Ensure iterator is left at limit position
-                                _index = limit.Index;
-                                return -1;
-                            }
-
-                            _index = index + byteIndex;
-
-                            if (block == limit.Block && _index > limit.Index)
-                            {
-                                // Ensure iterator is left at limit position
-                                _index = limit.Index;
-                                return -1;
-                            }
-
-                            return block.Array[index + byteIndex];
-                        }
-// Need unit tests to test Vector path
-#if !DEBUG
-                    }
-#endif
-                    var pCurrent = (block.DataFixedPtr + index);
-                    var pEnd = block == limit.Block ? block.DataFixedPtr + limit.Index + 1 : pCurrent + following;
-                    do
-                    {
-                        if (*pCurrent == byte0)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte0;
-                        }
-                        if (*pCurrent == byte1)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte1;
-                        }
-                        pCurrent++;
-                        index++;
-                    } while (pCurrent != pEnd);
-
-                    following = 0;
-                    break;
-                }
-            }
-        }
-
-        public int Seek(byte byte0, byte byte1, byte byte2)
-        {
-            var limit = new MemoryPoolIterator();
-            return Seek(byte0, byte1, byte2, ref limit);
-        }
-
-        public unsafe int Seek(
-            byte byte0,
-            byte byte1,
-            byte byte2,
-            ref MemoryPoolIterator limit)
-        {
-            var block = _block;
-            if (block == null)
-            {
-                return -1;
-            }
-
-            var index = _index;
-            var wasLastBlock = block.Next == null;
-            var following = block.End - index;
-            int byteIndex = int.MaxValue;
-
-            while (true)
-            {
-                while (following == 0)
-                {
-                    if ((block == limit.Block && index > limit.Index) ||
-                        wasLastBlock)
-                    {
-                        _block = block;
-                        // Ensure iterator is left at limit position
-                        _index = limit.Index;
-                        return -1;
-                    }
-                    block = block.Next;
-                    index = block.Start;
-                    wasLastBlock = block.Next == null;
-                    following = block.End - index;
-                }
-                var array = block.Array;
-                while (following > 0)
-                {
-// Need unit tests to test Vector path
-#if !DEBUG
-                    // Check will be Jitted away https://github.com/dotnet/coreclr/issues/1079
-                    if (Vector.IsHardwareAccelerated)
-                    {
-#endif
-                        if (following >= _vectorSpan)
-                        {
-                            var data = new Vector<byte>(array, index);
-
-                            var byteEquals = Vector.Equals(data, GetVector(byte0));
-                            byteEquals = Vector.ConditionalSelect(byteEquals, byteEquals, Vector.Equals(data, GetVector(byte1)));
-                            byteEquals = Vector.ConditionalSelect(byteEquals, byteEquals, Vector.Equals(data, GetVector(byte2)));
-
-                            if (!byteEquals.Equals(Vector<byte>.Zero))
-                            {
-                                byteIndex = LocateFirstFoundByte(byteEquals);
-                            }
-
-                            if (byteIndex == int.MaxValue)
-                            {
-                                following -= _vectorSpan;
-                                index += _vectorSpan;
-
-                                if (block == limit.Block && index > limit.Index)
-                                {
-                                    _block = block;
-                                    // Ensure iterator is left at limit position
-                                    _index = limit.Index;
-                                    return -1;
-                                }
-
-                                continue;
-                            }
-
-                            _block = block;
-
-                            _index = index + byteIndex;
-
-                            if (block == limit.Block && _index > limit.Index)
-                            {
-                                // Ensure iterator is left at limit position
-                                _index = limit.Index;
-                                return -1;
-                            }
-
-                            return block.Array[index + byteIndex];
-                        }
-// Need unit tests to test Vector path
-#if !DEBUG
-                    }
-#endif
-                    var pCurrent = (block.DataFixedPtr + index);
-                    var pEnd = block == limit.Block ? block.DataFixedPtr + limit.Index + 1 : pCurrent + following;
-                    do
-                    {
-                        if (*pCurrent == byte0)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte0;
-                        }
-                        if (*pCurrent == byte1)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte1;
-                        }
-                        if (*pCurrent == byte2)
-                        {
-                            _block = block;
-                            _index = index;
-                            return byte2;
-                        }
-                        pCurrent++;
-                        index++;
-                    } while (pCurrent != pEnd);
-
-                    following = 0;
-                    break;
-                }
-            }
-        }
-
-        /// <summary>
-        /// Locate the first of the found bytes
-        /// </summary>
-        /// <param  name="byteEquals"></param >
-        /// <returns>The first index of the result vector</returns>
-        // Force inlining (64 IL bytes, 91 bytes asm) Issue: https://github.com/dotnet/coreclr/issues/7386
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        internal static int LocateFirstFoundByte(Vector<byte> byteEquals)
-        {
-            var vector64 = Vector.AsVectorUInt64(byteEquals);
-            ulong longValue = 0;
-            var i = 0;
-            // Pattern unrolled by jit https://github.com/dotnet/coreclr/pull/8001
-            for (; i < Vector<ulong>.Count; i++)
-            {
-                longValue = vector64[i];
-                if (longValue == 0) continue;
-                break;
-            }
-
-            // Flag least significant power of two bit
-            var powerOfTwoFlag = (longValue ^ (longValue - 1));
-            // Shift all powers of two into the high byte and extract
-            var foundByteIndex = (int)((powerOfTwoFlag * _xorPowerOfTwoToHighByte) >> 57);
-            // Single LEA instruction with jitted const (using function result)
-            return i * 8 + foundByteIndex;
-        }
-
         /// <summary>
         /// Save the data at the current location then move to the next available space.
         /// </summary>
@@ -914,57 +244,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
             }
         }
 
-        public MemoryPoolIterator CopyTo(byte[] array, int offset, int count, out int actual)
-        {
-            var block = _block;
-            if (block == null)
-            {
-                actual = 0;
-                return this;
-            }
-
-            var index = _index;
-            var remaining = count;
-            while (true)
-            {
-                // Determine if we might attempt to copy data from block.Next before
-                // calculating "following" so we don't risk skipping data that could
-                // be added after block.End when we decide to copy from block.Next.
-                // block.End will always be advanced before block.Next is set.
-                var wasLastBlock = block.Next == null;
-                var following = block.End - index;
-                if (remaining <= following)
-                {
-                    actual = count;
-                    if (array != null)
-                    {
-                        Buffer.BlockCopy(block.Array, index, array, offset, remaining);
-                    }
-                    return new MemoryPoolIterator(block, index + remaining);
-                }
-                else if (wasLastBlock)
-                {
-                    actual = count - remaining + following;
-                    if (array != null)
-                    {
-                        Buffer.BlockCopy(block.Array, index, array, offset, following);
-                    }
-                    return new MemoryPoolIterator(block, index + following);
-                }
-                else
-                {
-                    if (array != null)
-                    {
-                        Buffer.BlockCopy(block.Array, index, array, offset, following);
-                    }
-                    offset += following;
-                    remaining -= following;
-                    block = block.Next;
-                    index = block.Start;
-                }
-            }
-        }
-
         public void CopyFrom(byte[] data)
         {
             CopyFrom(data, 0, data.Length);
@@ -1180,177 +459,5 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure
 
             CopyFrom(byteBuffer, position, _maxULongByteLength - position);
         }
-
-        public unsafe string GetAsciiString(ref MemoryPoolIterator end)
-        {
-            var block = _block;
-            if (block == null || end.IsDefault)
-            {
-                return null;
-            }
-
-            var length = GetLength(end);
-
-            if (length == 0)
-            {
-                return null;
-            }
-
-            var inputOffset = _index;
-
-            var asciiString = new string('\0', length);
-
-            fixed (char* outputStart = asciiString)
-            {
-                var output = outputStart;
-                var remaining = length;
-
-                var endBlock = end.Block;
-                var endIndex = end.Index;
-
-                var outputOffset = 0;
-                while (true)
-                {
-                    int following = (block != endBlock ? block.End : endIndex) - inputOffset;
-
-                    if (following > 0)
-                    {
-                        if (!AsciiUtilities.TryGetAsciiString(block.DataFixedPtr + inputOffset, output + outputOffset, following))
-                        {
-                            throw BadHttpRequestException.GetException(RequestRejectionReason.NonAsciiOrNullCharactersInInputString);
-                        }
-
-                        outputOffset += following;
-                        remaining -= following;
-                    }
-
-                    if (remaining == 0)
-                    {
-                        break;
-                    }
-
-                    block = block.Next;
-                    inputOffset = block.Start;
-                }
-            }
-
-            return asciiString;
-        }
-
-        public string GetUtf8String(ref MemoryPoolIterator end)
-        {
-            var block = _block;
-            if (block == null || end.IsDefault)
-            {
-                return default(string);
-            }
-
-            var index = _index;
-            if (end.Block == block)
-            {
-                return Encoding.UTF8.GetString(block.Array, index, end.Index - index);
-            }
-
-            var decoder = Encoding.UTF8.GetDecoder();
-
-            var length = GetLength(end);
-            var charLength = length;
-            // Worse case is 1 byte = 1 char
-            var chars = new char[charLength];
-            var charIndex = 0;
-
-            var remaining = length;
-            while (true)
-            {
-                int bytesUsed;
-                int charsUsed;
-                bool completed;
-                var following = block.End - index;
-                if (remaining <= following)
-                {
-                    decoder.Convert(
-                        block.Array,
-                        index,
-                        remaining,
-                        chars,
-                        charIndex,
-                        charLength - charIndex,
-                        true,
-                        out bytesUsed,
-                        out charsUsed,
-                        out completed);
-                    return new string(chars, 0, charIndex + charsUsed);
-                }
-                else if (block.Next == null)
-                {
-                    decoder.Convert(
-                        block.Array,
-                        index,
-                        following,
-                        chars,
-                        charIndex,
-                        charLength - charIndex,
-                        true,
-                        out bytesUsed,
-                        out charsUsed,
-                        out completed);
-                    return new string(chars, 0, charIndex + charsUsed);
-                }
-                else
-                {
-                    decoder.Convert(
-                        block.Array,
-                        index,
-                        following,
-                        chars,
-                        charIndex,
-                        charLength - charIndex,
-                        false,
-                        out bytesUsed,
-                        out charsUsed,
-                        out completed);
-                    charIndex += charsUsed;
-                    remaining -= following;
-                    block = block.Next;
-                    index = block.Start;
-                }
-            }
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public ArraySegment<byte> GetArraySegment(MemoryPoolIterator end)
-        {
-            var block = _block;
-            if (block == null || end.IsDefault)
-            {
-                return default(ArraySegment<byte>);
-            }
-
-            var index = _index;
-            if (end.Block == block)
-            {
-                return new ArraySegment<byte>(block.Array, index, end.Index - index);
-            }
-
-            return GetArraySegmentMultiBlock(ref end);
-        }
-
-        [MethodImpl(MethodImplOptions.NoInlining)]
-        private ArraySegment<byte> GetArraySegmentMultiBlock(ref MemoryPoolIterator end)
-        {
-            var length = GetLength(end);
-            var array = new byte[length];
-            CopyTo(array, 0, length, out length);
-            return new ArraySegment<byte>(array, 0, length);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static Vector<byte> GetVector(byte vectorByte)
-        {
-            // Vector<byte> .ctor doesn't become an intrinsic due to detection issue
-            // However this does cause it to become an intrinsic (with additional multiply and reg->reg copy)
-            // https://github.com/dotnet/coreclr/issues/7459#issuecomment-253965670
-            return Vector.AsVectorByte(new Vector<uint>(vectorByte * 0x01010101u));
-        }
     }
 }

src/Microsoft.AspNetCore.Server.Kestrel/KestrelServer.cs

@@ -142,8 +142,16 @@ namespace Microsoft.AspNetCore.Server.Kestrel
                 }
                 else if (!hasListenOptions && !hasServerAddresses)
                 {
-                    _logger.LogDebug($"No listening endpoints were configured. Binding to {Constants.DefaultIPEndPoint} by default.");
+                    _logger.LogDebug($"No listening endpoints were configured. Binding to {Constants.DefaultServerAddress} by default.");
-                    listenOptions.Add(new ListenOptions(Constants.DefaultIPEndPoint));
+
+                    // "localhost" for both IPv4 and IPv6 can't be represented as an IPEndPoint.
+                    StartLocalhost(engine, ServerAddress.FromUrl(Constants.DefaultServerAddress));
+
+                    // If StartLocalhost doesn't throw, there is at least one listener.
+                    // The port cannot change for "localhost".
+                    _serverAddresses.Addresses.Add(Constants.DefaultServerAddress);
+
+                    return;
                 }
                 else if (!hasListenOptions)
                 {

src/Microsoft.AspNetCore.Server.Kestrel/Microsoft.AspNetCore.Server.Kestrel.csproj

@@ -18,10 +18,9 @@
     <PackageReference Include="Microsoft.Extensions.TaskCache.Sources" Version="1.2.0-*" PrivateAssets="All" />
     <PackageReference Include="System.Numerics.Vectors" Version="$(CoreFxVersion)" />
     <PackageReference Include="System.Threading.Tasks.Extensions" Version="$(CoreFxVersion)" />
-    
+    <PackageReference Include="System.IO.Pipelines" Version="$(CoreFxLabsPipelinesVersion)" />
-    <PackageReference Include="System.IO.Pipelines" Version="0.1.0-*" />
+    <PackageReference Include="System.IO.Pipelines.Text.Primitives" Version="$(CoreFxLabsVersion)" />
-    <PackageReference Include="System.IO.Pipelines.Text.Primitives" Version="0.1.0-*" />
+    <PackageReference Include="System.Text.Encodings.Web.Utf8" Version="$(CoreFxLabsVersion)" />
-    <PackageReference Include="System.Text.Encodings.Web.Utf8" Version="0.1.0-*" />
   </ItemGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.3' ">

test/Microsoft.AspNetCore.Server.Kestrel.FunctionalTests/AddressRegistrationTests.cs

@@ -14,6 +14,7 @@ using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Hosting.Server.Features;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Extensions;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.AspNetCore.Testing;
 using Microsoft.AspNetCore.Testing.xunit;
 using Microsoft.Extensions.DependencyInjection;
@@ -129,31 +130,45 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
             }
         }
 
-        [ConditionalFact(Skip = "Waiting on https://github.com/aspnet/Hosting/issues/917")]
+        [ConditionalFact]
         [PortSupportedCondition(5000)]
-        public async Task DefaultsToPort5000()
+        public Task DefaultsServerAddress_BindsToIPv4()
+        {
+            return RegisterDefaultServerAddresses_Success(new[] { "http://127.0.0.1:5000" });
+        }
+
+        [ConditionalFact]
+        [IPv6SupportedCondition]
+        [PortSupportedCondition(5000)]
+        public Task DefaultsServerAddress_BindsToIPv6()
+        {
+            return RegisterDefaultServerAddresses_Success(new[] { "http://127.0.0.1:5000", "http://[::1]:5000" });
+        }
+
+        private async Task RegisterDefaultServerAddresses_Success(IEnumerable<string> addresses)
         {
             var testLogger = new TestApplicationErrorLogger();
 
             var hostBuilder = new WebHostBuilder()
                .UseKestrel()
                .ConfigureServices(services =>
-                {
+               {
-                    services.AddSingleton<ILoggerFactory>(new KestrelTestLoggerFactory(testLogger));
+                   services.AddSingleton<ILoggerFactory>(new KestrelTestLoggerFactory(testLogger));
-                })
+               })
                .Configure(ConfigureEchoAddress);
 
             using (var host = hostBuilder.Build())
             {
                 host.Start();
 
-                var debugLog = testLogger.Messages.Single(log => log.LogLevel == LogLevel.Debug);
+                Assert.Equal(5000, host.GetPort());
-                Assert.True(debugLog.Message.Contains("default"));
+                Assert.Single(testLogger.Messages, log => log.LogLevel == LogLevel.Debug &&
+                    string.Equals($"No listening endpoints were configured. Binding to {Constants.DefaultServerAddress} by default.",
+                    log.Message, StringComparison.Ordinal));
 
-                foreach (var testUrl in new[] { "http://127.0.0.1:5000", "http://localhost:5000" })
+                foreach (var address in addresses)
                 {
-                    var response = await HttpClientSlim.GetStringAsync(testUrl);
+                    Assert.Equal(new Uri(address).ToString(), await HttpClientSlim.GetStringAsync(address));
-                    Assert.Equal(new Uri(testUrl).ToString(), response);
                 }
             }
         }

test/Microsoft.AspNetCore.Server.Kestrel.FunctionalTests/BadHttpRequestTests.cs

@@ -2,10 +2,12 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System.Collections.Generic;
-using System.Linq;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.AspNetCore.Testing;
 using Microsoft.Extensions.Internal;
+using Microsoft.Extensions.Logging;
+using Moq;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
@@ -14,106 +16,102 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
     {
         [Theory]
         [MemberData(nameof(InvalidRequestLineData))]
-        public async Task TestInvalidRequestLines(string request)
+        public Task TestInvalidRequestLines(string request, string expectedExceptionMessage)
         {
-            using (var server = new TestServer(context => TaskCache.CompletedTask))
+            return TestBadRequest(
-            {
+                request,
-                using (var connection = server.CreateConnection())
+                "400 Bad Request",
-                {
+                expectedExceptionMessage);
-                    await connection.SendAll(request);
-                    await ReceiveBadRequestResponse(connection, "400 Bad Request", server.Context.DateHeaderValue);
-                }
-            }
         }
 
         [Theory]
         [MemberData(nameof(UnrecognizedHttpVersionData))]
-        public async Task TestInvalidRequestLinesWithUnrecognizedVersion(string httpVersion)
+        public Task TestInvalidRequestLinesWithUnrecognizedVersion(string httpVersion)
         {
-            using (var server = new TestServer(context => TaskCache.CompletedTask))
+            return TestBadRequest(
-            {
+                $"GET / {httpVersion}\r\n",
-                using (var connection = server.CreateConnection())
+                "505 HTTP Version Not Supported",
-                {
+                $"Unrecognized HTTP version: {httpVersion}");
-                    await connection.SendAll($"GET / {httpVersion}\r\n");
-                    await ReceiveBadRequestResponse(connection, "505 HTTP Version Not Supported", server.Context.DateHeaderValue);
-                }
-            }
         }
 
         [Theory]
         [MemberData(nameof(InvalidRequestHeaderData))]
-        public async Task TestInvalidHeaders(string rawHeaders)
+        public Task TestInvalidHeaders(string rawHeaders, string expectedExceptionMessage)
         {
-            using (var server = new TestServer(context => TaskCache.CompletedTask))
+            return TestBadRequest(
-            {
+                $"GET / HTTP/1.1\r\n{rawHeaders}",
-                using (var connection = server.CreateConnection())
+                "400 Bad Request",
-                {
+                expectedExceptionMessage);
-                    await connection.SendAll($"GET / HTTP/1.1\r\n{rawHeaders}");
-                    await ReceiveBadRequestResponse(connection, "400 Bad Request", server.Context.DateHeaderValue);
-                }
-            }
         }
 
-        [Fact]
+        [Theory]
-        public async Task BadRequestWhenHeaderNameContainsNonASCIICharacters()
+        [InlineData("Hea\0der: value", "Invalid characters in header name.")]
+        [InlineData("Header: va\0lue", "Malformed request: invalid headers.")]
+        [InlineData("Head\x80r: value", "Invalid characters in header name.")]
+        [InlineData("Header: valu\x80", "Malformed request: invalid headers.")]
+        public Task BadRequestWhenHeaderNameContainsNonASCIIOrNullCharacters(string header, string expectedExceptionMessage)
         {
-            using (var server = new TestServer(context => { return Task.FromResult(0); }))
+            return TestBadRequest(
-            {
+                $"GET / HTTP/1.1\r\n{header}\r\n\r\n",
-                using (var connection = server.CreateConnection())
+                "400 Bad Request",
-                {
+                expectedExceptionMessage);
-                    await connection.SendAll(
-                        "GET / HTTP/1.1",
-                        "H\u00eb\u00e4d\u00ebr: value",
-                        "",
-                        "");
-                    await ReceiveBadRequestResponse(connection, "400 Bad Request", server.Context.DateHeaderValue);
-                }
-            }
         }
 
         [Theory]
         [InlineData("POST")]
         [InlineData("PUT")]
-        public async Task BadRequestIfMethodRequiresLengthButNoContentLengthOrTransferEncodingInRequest(string method)
+        public Task BadRequestIfMethodRequiresLengthButNoContentLengthOrTransferEncodingInRequest(string method)
         {
-            using (var server = new TestServer(context => { return Task.FromResult(0); }))
+            return TestBadRequest(
-            {
+                $"{method} / HTTP/1.1\r\n\r\n",
-                using (var connection = server.CreateConnection())
+                "411 Length Required",
-                {
+                $"{method} request contains no Content-Length or Transfer-Encoding header");
-                    await connection.Send($"{method} / HTTP/1.1\r\n\r\n");
-                    await ReceiveBadRequestResponse(connection, "411 Length Required", server.Context.DateHeaderValue);
-                }
-            }
         }
 
         [Theory]
         [InlineData("POST")]
         [InlineData("PUT")]
-        public async Task BadRequestIfMethodRequiresLengthButNoContentLengthInHttp10Request(string method)
+        public Task BadRequestIfMethodRequiresLengthButNoContentLengthInHttp10Request(string method)
         {
-            using (var server = new TestServer(context => { return Task.FromResult(0); }))
+            return TestBadRequest(
-            {
+                $"{method} / HTTP/1.0\r\n\r\n",
-                using (var connection = server.CreateConnection())
+                "400 Bad Request",
-                {
+                $"{method} request contains no Content-Length header");
-                    await connection.Send($"{method} / HTTP/1.0\r\n\r\n");
-                    await ReceiveBadRequestResponse(connection, "400 Bad Request", server.Context.DateHeaderValue);
-                }
-            }
         }
 
         [Theory]
         [InlineData("NaN")]
         [InlineData("-1")]
-        public async Task BadRequestIfContentLengthInvalid(string contentLength)
+        public Task BadRequestIfContentLengthInvalid(string contentLength)
         {
-            using (var server = new TestServer(context => { return Task.FromResult(0); }))
+            return TestBadRequest(
+                $"POST / HTTP/1.1\r\nContent-Length: {contentLength}\r\n\r\n",
+                "400 Bad Request",
+                $"Invalid content length: {contentLength}");
+        }
+
+        private async Task TestBadRequest(string request, string expectedResponseStatusCode, string expectedExceptionMessage)
+        {
+            BadHttpRequestException loggedException = null;
+            var mockKestrelTrace = new Mock<IKestrelTrace>();
+            mockKestrelTrace
+                .Setup(trace => trace.IsEnabled(LogLevel.Information))
+                .Returns(true);
+            mockKestrelTrace
+                .Setup(trace => trace.ConnectionBadRequest(It.IsAny<string>(), It.IsAny<BadHttpRequestException>()))
+                .Callback<string, BadHttpRequestException>((connectionId, exception) => loggedException = exception);
+
+            using (var server = new TestServer(context => TaskCache.CompletedTask, new TestServiceContext { Log = mockKestrelTrace.Object }))
             {
                 using (var connection = server.CreateConnection())
                 {
-                    await connection.SendAll($"GET / HTTP/1.1\r\nContent-Length: {contentLength}\r\n\r\n");
+                    await connection.SendAll(request);
-                    await ReceiveBadRequestResponse(connection, "400 Bad Request", server.Context.DateHeaderValue);
+                    await ReceiveBadRequestResponse(connection, expectedResponseStatusCode, server.Context.DateHeaderValue);
                 }
             }
+
+            mockKestrelTrace.Verify(trace => trace.ConnectionBadRequest(It.IsAny<string>(), It.IsAny<BadHttpRequestException>()));
+            Assert.Equal(expectedExceptionMessage, loggedException.Message);
         }
 
         private async Task ReceiveBadRequestResponse(TestConnection connection, string expectedResponseStatusCode, string expectedDateHeaderValue)
@@ -127,10 +125,33 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
                 "");
         }
 
-        public static IEnumerable<object> InvalidRequestLineData => HttpParsingData.InvalidRequestLineData.Select(data => new[] { data[0] });
+        public static TheoryData<string, string> InvalidRequestLineData
+        {
+            get
+            {
+                var data = new TheoryData<string, string>();
+
+                foreach (var requestLine in HttpParsingData.RequestLineInvalidData)
+                {
+                    data.Add(requestLine, $"Invalid request line: {requestLine.Replace("\r", "<0x0D>").Replace("\n", "<0x0A>")}");
+                }
+
+                foreach (var requestLine in HttpParsingData.RequestLineWithEncodedNullCharInTargetData)
+                {
+                    data.Add(requestLine, "Invalid request line.");
+                }
+
+                foreach (var requestLine in HttpParsingData.RequestLineWithNullCharInTargetData)
+                {
+                    data.Add(requestLine, "Invalid request line.");
+                }
+
+                return data;
+            }
+        }
 
         public static TheoryData<string> UnrecognizedHttpVersionData => HttpParsingData.UnrecognizedHttpVersionData;
 
-        public static IEnumerable<object[]> InvalidRequestHeaderData => HttpParsingData.InvalidRequestHeaderData.Select(data => new[] { data[0] });
+        public static IEnumerable<object[]> InvalidRequestHeaderData => HttpParsingData.RequestHeaderInvalidData;
     }
 }

test/Microsoft.AspNetCore.Server.Kestrel.FunctionalTests/SystemdActivation/docker.sh

@@ -2,13 +2,8 @@
 
 set -e
 
-# Ensure that dotnet is added to the PATH.
-# build.sh should always be run before this script to create the .build/ directory and restore packages.
 scriptDir=$(dirname "${BASH_SOURCE[0]}")
-repoDir=$(cd $scriptDir/../../.. && pwd)
+~/.dotnet/dotnet publish -f netcoreapp1.1 ./samples/SampleApp/
-source ./.build/KoreBuild.sh -r $repoDir --quiet
-
-dotnet publish -f netcoreapp1.1 ./samples/SampleApp/
 cp -R ./samples/SampleApp/bin/Debug/netcoreapp1.1/publish/ $scriptDir
 cp -R ~/.dotnet/ $scriptDir
 

test/Microsoft.AspNetCore.Server.Kestrel.Performance/FrameParsingOverhead.cs

@@ -0,0 +1,135 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.IO.Pipelines;
+using System.Text;
+using BenchmarkDotNet.Attributes;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
+using Microsoft.AspNetCore.Testing;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Performance
+{
+    [Config(typeof(CoreConfig))]
+    public class FrameParsingOverhead
+    {
+        private const int InnerLoopCount = 512;
+
+        public ReadableBuffer _buffer;
+        public Frame<object> _frame;
+
+        [Setup]
+        public void Setup()
+        {
+            var connectionContext = new MockConnection(new KestrelServerOptions());
+            connectionContext.ListenerContext.ServiceContext.HttpParserFactory = frame => NullParser.Instance;
+
+            _frame = new Frame<object>(application: null, context: connectionContext);
+        }
+
+        [Benchmark(Baseline = true, OperationsPerInvoke = InnerLoopCount)]
+        public void FrameOverheadTotal()
+        {
+            for (var i = 0; i < InnerLoopCount; i++)
+            {
+                ParseRequest();
+            }
+        }
+
+        [Benchmark(OperationsPerInvoke = InnerLoopCount)]
+        public void FrameOverheadRequestLine()
+        {
+            for (var i = 0; i < InnerLoopCount; i++)
+            {
+                ParseRequestLine();
+            }
+        }
+
+        [Benchmark(OperationsPerInvoke = InnerLoopCount)]
+        public void FrameOverheadRequestHeaders()
+        {
+            for (var i = 0; i < InnerLoopCount; i++)
+            {
+                ParseRequestHeaders();
+            }
+        }
+
+        private void ParseRequest()
+        {
+            _frame.Reset();
+
+            if (!_frame.TakeStartLine(_buffer, out var consumed, out var examined))
+            {
+                RequestParsing.ThrowInvalidRequestLine();
+            }
+
+            _frame.InitializeHeaders();
+
+            if (!_frame.TakeMessageHeaders(_buffer, out consumed, out examined))
+            {
+                RequestParsing.ThrowInvalidRequestHeaders();
+            }
+        }
+
+        private void ParseRequestLine()
+        {
+            _frame.Reset();
+
+            if (!_frame.TakeStartLine(_buffer, out var consumed, out var examined))
+            {
+                RequestParsing.ThrowInvalidRequestLine();
+            }
+        }
+
+        private void ParseRequestHeaders()
+        {
+            _frame.Reset();
+            _frame.InitializeHeaders();
+
+            if (!_frame.TakeMessageHeaders(_buffer, out var consumed, out var examined))
+            {
+                RequestParsing.ThrowInvalidRequestHeaders();
+            }
+        }
+
+        private class NullParser : IHttpParser
+        {
+            private readonly byte[] _target = Encoding.ASCII.GetBytes("/plaintext");
+            private readonly byte[] _hostHeaderName = Encoding.ASCII.GetBytes("Host");
+            private readonly byte[] _hostHeaderValue = Encoding.ASCII.GetBytes("www.example.com");
+            private readonly byte[] _acceptHeaderName = Encoding.ASCII.GetBytes("Accept");
+            private readonly byte[] _acceptHeaderValue = Encoding.ASCII.GetBytes("text/plain,text/html;q=0.9,application/xhtml+xml;q=0.9,application/xml;q=0.8,*/*;q=0.7\r\n\r\n");
+            private readonly byte[] _connectionHeaderName = Encoding.ASCII.GetBytes("Connection");
+            private readonly byte[] _connectionHeaderValue = Encoding.ASCII.GetBytes("keep-alive");
+
+            public static readonly NullParser Instance = new NullParser();
+
+            public bool ParseHeaders<T>(T handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined, out int consumedBytes) where T : IHttpHeadersHandler
+            {
+                handler.OnHeader(new Span<byte>(_hostHeaderName), new Span<byte>(_hostHeaderValue));
+                handler.OnHeader(new Span<byte>(_acceptHeaderName), new Span<byte>(_acceptHeaderValue));
+                handler.OnHeader(new Span<byte>(_connectionHeaderName), new Span<byte>(_connectionHeaderValue));
+
+                consumedBytes = 0;
+                consumed = buffer.Start;
+                examined = buffer.End;
+
+                return true;
+            }
+
+            public bool ParseRequestLine<T>(T handler, ReadableBuffer buffer, out ReadCursor consumed, out ReadCursor examined) where T : IHttpRequestLineHandler
+            {
+                handler.OnStartLine(HttpMethod.Get, HttpVersion.Http11, new Span<byte>(_target), new Span<byte>(_target), Span<byte>.Empty, Span<byte>.Empty);
+
+                consumed = buffer.Start;
+                examined = buffer.End;
+
+                return true;
+            }
+
+            public void Reset()
+            {
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Server.Kestrel.Performance/KestrelHttpParser.cs

@@ -0,0 +1,77 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.IO.Pipelines;
+using BenchmarkDotNet.Attributes;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Performance
+{
+    [Config(typeof(CoreConfig))]
+
+    public class KestrelHttpParser : IHttpRequestLineHandler, IHttpHeadersHandler
+    {
+        private readonly Internal.Http.KestrelHttpParser _parser = new Internal.Http.KestrelHttpParser(log: null);
+
+        private ReadableBuffer _buffer;
+
+        [Benchmark(Baseline = true, OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
+        public void PlaintextTechEmpower()
+        {
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
+            {
+                InsertData(RequestParsingData.PlaintextTechEmpowerRequest);
+                ParseData();
+            }
+        }
+
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
+        public void LiveAspNet()
+        {
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
+            {
+                InsertData(RequestParsingData.LiveaspnetRequest);
+                ParseData();
+            }
+        }
+
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
+        public void Unicode()
+        {
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
+            {
+                InsertData(RequestParsingData.UnicodeRequest);
+                ParseData();
+            }
+        }
+
+        private void InsertData(byte[] data)
+        {
+            _buffer = ReadableBuffer.Create(data);
+        }
+
+        private void ParseData()
+        {
+            if (!_parser.ParseRequestLine(this, _buffer, out var consumed, out var examined))
+            {
+                RequestParsing.ThrowInvalidRequestHeaders();
+            }
+
+            _buffer = _buffer.Slice(consumed, _buffer.End);
+
+            if (!_parser.ParseHeaders(this, _buffer, out consumed, out examined, out var consumedBytes))
+            {
+                RequestParsing.ThrowInvalidRequestHeaders();
+            }
+        }
+
+        public void OnStartLine(HttpMethod method, HttpVersion version, Span<byte> target, Span<byte> path, Span<byte> query, Span<byte> customMethod)
+        {
+        }
+
+        public void OnHeader(Span<byte> name, Span<byte> value)
+        {
+        }
+    }
+}

test/Microsoft.AspNetCore.Server.Kestrel.Performance/Microsoft.AspNetCore.Server.Kestrel.Performance.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <Import Project="..\..\build\common.props" />
 
@@ -6,6 +6,7 @@
     <TargetFramework>netcoreapp1.1</TargetFramework>
     <OutputType>Exe</OutputType>
     <ServerGarbageCollection>true</ServerGarbageCollection>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
@@ -22,7 +23,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.10.2.*" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.10.3" />
     <PackageReference Include="Moq" Version="4.6.36-*" />
   </ItemGroup>
 

test/Microsoft.AspNetCore.Server.Kestrel.Performance/Program.cs

@@ -40,10 +40,18 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
             {
                 BenchmarkRunner.Run<PipeThroughput>();
             }
-            if (type.HasFlag(BenchmarkType.KnownStrings)) 
+            if (type.HasFlag(BenchmarkType.KnownStrings))
             {
                 BenchmarkRunner.Run<KnownStrings>();
             }
+            if (type.HasFlag(BenchmarkType.KestrelHttpParser))
+            {
+                BenchmarkRunner.Run<KestrelHttpParser>();
+            }
+            if (type.HasFlag(BenchmarkType.FrameParsingOverhead))
+            {
+                BenchmarkRunner.Run<FrameParsingOverhead>();
+            }
         }
     }
 
@@ -54,6 +62,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
         Writing = 2,
         Throughput = 4,
         KnownStrings = 8,
+        KestrelHttpParser = 16,
+        FrameParsingOverhead = 32,
         // add new ones in powers of two - e.g. 2,4,8,16...
 
         All = uint.MaxValue

test/Microsoft.AspNetCore.Server.Kestrel.Performance/RequestParsing.cs

@@ -3,128 +3,101 @@
 
 using System;
 using System.IO.Pipelines;
-using System.Linq;
-using System.Text;
 using BenchmarkDotNet.Attributes;
-using Microsoft.AspNetCore.Server.Kestrel.Internal;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
-using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
 using Microsoft.AspNetCore.Testing;
-using MemoryPool = Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure.MemoryPool;
-using RequestLineStatus = Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Frame.RequestLineStatus;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Performance
 {
     [Config(typeof(CoreConfig))]
     public class RequestParsing
     {
-        private const int InnerLoopCount = 512;
+        [Params(typeof(Internal.Http.KestrelHttpParser))]
-        private const int Pipelining = 16;
-
-        private const string plaintextRequest = "GET /plaintext HTTP/1.1\r\nHost: www.example.com\r\n\r\n";
-
-        private const string liveaspnetRequest = "GET https://live.asp.net/ HTTP/1.1\r\n" +
-            "Host: live.asp.net\r\n" +
-            "Connection: keep-alive\r\n" +
-            "Upgrade-Insecure-Requests: 1\r\n" +
-            "User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36\r\n" +
-            "Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8\r\n" +
-            "DNT: 1\r\n" +
-            "Accept-Encoding: gzip, deflate, sdch, br\r\n" +
-            "Accept-Language: en-US,en;q=0.8\r\n" +
-            "Cookie: __unam=7a67379-1s65dc575c4-6d778abe-1; omniID=9519gfde_3347_4762_8762_df51458c8ec2\r\n\r\n";
-
-        private const string unicodeRequest =
-            "GET http://stackoverflow.com/questions/40148683/why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric HTTP/1.1\r\n" +
-            "Accept: text/html, application/xhtml+xml, image/jxr, */*\r\n" +
-            "Accept-Language: en-US,en-GB;q=0.7,en;q=0.3\r\n" +
-            "User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36 Edge/15.14965\r\n" +
-            "Accept-Encoding: gzip, deflate\r\n" +
-            "Host: stackoverflow.com\r\n" +
-            "Connection: Keep-Alive\r\n" +
-            "Cache-Control: max-age=0\r\n" +
-            "Upgrade-Insecure-Requests: 1\r\n" +
-            "DNT: 1\r\n" +
-            "Referer: http://stackoverflow.com/?tab=month\r\n" +
-            "Pragma: no-cache\r\n" +
-            "Cookie: prov=20629ccd-8b0f-e8ef-2935-cd26609fc0bc; __qca=P0-1591065732-1479167353442; _ga=GA1.2.1298898376.1479167354; _gat=1; sgt=id=9519gfde_3347_4762_8762_df51458c8ec2; acct=t=why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric&s=why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric\r\n\r\n";
-
-        private static readonly byte[] _plaintextPipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(plaintextRequest, Pipelining)));
-        private static readonly byte[] _plaintextRequest = Encoding.ASCII.GetBytes(plaintextRequest);
-
-        private static readonly byte[] _liveaspnentPipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(liveaspnetRequest, Pipelining)));
-        private static readonly byte[] _liveaspnentRequest = Encoding.ASCII.GetBytes(liveaspnetRequest);
-
-        private static readonly byte[] _unicodePipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(unicodeRequest, Pipelining)));
-        private static readonly byte[] _unicodeRequest = Encoding.ASCII.GetBytes(unicodeRequest);
-
-        [Params(typeof(KestrelHttpParser))]
         public Type ParserType { get; set; }
 
-        [Benchmark(Baseline = true, OperationsPerInvoke = InnerLoopCount)]
+        public IPipe Pipe { get; set; }
-        public void ParsePlaintext()
+
+        public Frame<object> Frame { get; set; }
+
+        public PipeFactory PipelineFactory { get; set; }
+
+        [Setup]
+        public void Setup()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            var connectionContext = new MockConnection(new KestrelServerOptions());
+            connectionContext.ListenerContext.ServiceContext.HttpParserFactory = frame => (IHttpParser)Activator.CreateInstance(ParserType, frame.ConnectionContext.ListenerContext.ServiceContext.Log);
+
+            Frame = new Frame<object>(application: null, context: connectionContext);
+            PipelineFactory = new PipeFactory();
+            Pipe = PipelineFactory.Create();
+        }
+
+        [Benchmark(Baseline = true, OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
+        public void PlaintextTechEmpower()
+        {
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_plaintextRequest);
+                InsertData(RequestParsingData.PlaintextTechEmpowerRequest);
                 ParseData();
             }
         }
 
-        [Benchmark(OperationsPerInvoke = InnerLoopCount * Pipelining)]
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount * RequestParsingData.Pipelining)]
-        public void ParsePipelinedPlaintext()
+        public void PipelinedPlaintextTechEmpower()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_plaintextPipelinedRequests);
+                InsertData(RequestParsingData.PlaintextTechEmpowerPipelinedRequests);
                 ParseData();
             }
         }
 
-        [Benchmark(OperationsPerInvoke = InnerLoopCount)]
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
-        public void ParseLiveAspNet()
+        public void LiveAspNet()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_liveaspnentRequest);
+                InsertData(RequestParsingData.LiveaspnetRequest);
                 ParseData();
             }
         }
 
-        [Benchmark(OperationsPerInvoke = InnerLoopCount * Pipelining)]
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount * RequestParsingData.Pipelining)]
-        public void ParsePipelinedLiveAspNet()
+        public void PipelinedLiveAspNet()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_liveaspnentPipelinedRequests);
+                InsertData(RequestParsingData.LiveaspnetPipelinedRequests);
                 ParseData();
             }
         }
 
-        [Benchmark(OperationsPerInvoke = InnerLoopCount)]
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount)]
-        public void ParseUnicode()
+        public void Unicode()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_unicodeRequest);
+                InsertData(RequestParsingData.UnicodeRequest);
                 ParseData();
             }
         }
 
-        [Benchmark(OperationsPerInvoke = InnerLoopCount * Pipelining)]
+        [Benchmark(OperationsPerInvoke = RequestParsingData.InnerLoopCount * RequestParsingData.Pipelining)]
-        public void ParseUnicodePipelined()
+        public void UnicodePipelined()
         {
-            for (var i = 0; i < InnerLoopCount; i++)
+            for (var i = 0; i < RequestParsingData.InnerLoopCount; i++)
             {
-                InsertData(_unicodePipelinedRequests);
+                InsertData(RequestParsingData.UnicodePipelinedRequests);
                 ParseData();
             }
         }
 
         private void InsertData(byte[] bytes)
         {
+            var buffer = Pipe.Writer.Alloc(2048);
+            buffer.WriteFast(bytes);
             // There should not be any backpressure and task completes immediately
-            Pipe.Writer.WriteAsync(bytes).GetAwaiter().GetResult();
+            buffer.FlushAsync().GetAwaiter().GetResult();
         }
 
         private void ParseData()
@@ -143,11 +116,9 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
 
                 Frame.Reset();
 
-                ReadCursor consumed;
+                if (!Frame.TakeStartLine(readableBuffer, out var consumed, out var examined))
-                ReadCursor examined;
-                if (!Frame.TakeStartLine(readableBuffer, out consumed, out examined))
                 {
-                    ThrowInvalidStartLine();
+                    ThrowInvalidRequestLine();
                 }
                 Pipe.Reader.Advance(consumed, examined);
 
@@ -156,40 +127,23 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
 
                 Frame.InitializeHeaders();
 
-                if (!Frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)Frame.RequestHeaders, out consumed, out examined))
+                if (!Frame.TakeMessageHeaders(readableBuffer, out consumed, out examined))
                 {
-                    ThrowInvalidMessageHeaders();
+                    ThrowInvalidRequestHeaders();
                 }
                 Pipe.Reader.Advance(consumed, examined);
             }
             while (true);
         }
 
-        private void ThrowInvalidStartLine()
+        public static void ThrowInvalidRequestLine()
         {
-            throw new InvalidOperationException("Invalid StartLine");
+            throw new InvalidOperationException("Invalid request line");
         }
 
-        private void ThrowInvalidMessageHeaders()
+        public static void ThrowInvalidRequestHeaders()
         {
-            throw new InvalidOperationException("Invalid MessageHeaders");
+            throw new InvalidOperationException("Invalid request headers");
         }
-
-        [Setup]
-        public void Setup()
-        {
-            var connectionContext = new MockConnection(new KestrelServerOptions());
-            connectionContext.ListenerContext.ServiceContext.HttpParserFactory = frame => (IHttpParser)Activator.CreateInstance(ParserType, frame.ConnectionContext.ListenerContext.ServiceContext.Log);
-
-            Frame = new Frame<object>(application: null, context: connectionContext);
-            PipelineFactory = new PipeFactory();
-            Pipe = PipelineFactory.Create();
-        }
-
-        public IPipe Pipe { get; set; }
-
-        public Frame<object> Frame { get; set; }
-
-        public PipeFactory PipelineFactory { get; set; }
     }
 }

test/Microsoft.AspNetCore.Server.Kestrel.Performance/RequestParsingData.cs

@@ -0,0 +1,62 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Linq;
+using System.Text;
+using BenchmarkDotNet.Attributes;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Performance
+{
+    [Config(typeof(CoreConfig))]
+    public class RequestParsingData
+    {
+        public const int InnerLoopCount = 512;
+
+        public const int Pipelining = 16;
+
+        private const string _plaintextTechEmpowerRequest =
+            "GET /plaintext HTTP/1.1\r\n" +
+            "Host: localhost\r\n" +
+            "Accept: text/plain,text/html;q=0.9,application/xhtml+xml;q=0.9,application/xml;q=0.8,*/*;q=0.7\r\n" +
+            "Connection: keep-alive\r\n" +
+            "\r\n";
+
+        private const string _liveaspnetRequest =
+            "GET https://live.asp.net/ HTTP/1.1\r\n" +
+            "Host: live.asp.net\r\n" +
+            "Connection: keep-alive\r\n" +
+            "Upgrade-Insecure-Requests: 1\r\n" +
+            "User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36\r\n" +
+            "Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8\r\n" +
+            "DNT: 1\r\n" +
+            "Accept-Encoding: gzip, deflate, sdch, br\r\n" +
+            "Accept-Language: en-US,en;q=0.8\r\n" +
+            "Cookie: __unam=7a67379-1s65dc575c4-6d778abe-1; omniID=9519gfde_3347_4762_8762_df51458c8ec2\r\n" +
+            "\r\n";
+
+        private const string _unicodeRequest =
+            "GET http://stackoverflow.com/questions/40148683/why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric HTTP/1.1\r\n" +
+            "Accept: text/html, application/xhtml+xml, image/jxr, */*\r\n" +
+            "Accept-Language: en-US,en-GB;q=0.7,en;q=0.3\r\n" +
+            "User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36 Edge/15.14965\r\n" +
+            "Accept-Encoding: gzip, deflate\r\n" +
+            "Host: stackoverflow.com\r\n" +
+            "Connection: Keep-Alive\r\n" +
+            "Cache-Control: max-age=0\r\n" +
+            "Upgrade-Insecure-Requests: 1\r\n" +
+            "DNT: 1\r\n" +
+            "Referer: http://stackoverflow.com/?tab=month\r\n" +
+            "Pragma: no-cache\r\n" +
+            "Cookie: prov=20629ccd-8b0f-e8ef-2935-cd26609fc0bc; __qca=P0-1591065732-1479167353442; _ga=GA1.2.1298898376.1479167354; _gat=1; sgt=id=9519gfde_3347_4762_8762_df51458c8ec2; acct=t=why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric&s=why-is-%e0%a5%a7%e0%a5%a8%e0%a5%a9-numeric\r\n" +
+            "\r\n";
+
+        public static readonly byte[] PlaintextTechEmpowerPipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(_plaintextTechEmpowerRequest, Pipelining)));
+        public static readonly byte[] PlaintextTechEmpowerRequest = Encoding.ASCII.GetBytes(_plaintextTechEmpowerRequest);
+
+        public static readonly byte[] LiveaspnetPipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(_liveaspnetRequest, Pipelining)));
+        public static readonly byte[] LiveaspnetRequest = Encoding.ASCII.GetBytes(_liveaspnetRequest);
+
+        public static readonly byte[] UnicodePipelinedRequests = Encoding.ASCII.GetBytes(string.Concat(Enumerable.Repeat(_unicodeRequest, Pipelining)));
+        public static readonly byte[] UnicodeRequest = Encoding.ASCII.GetBytes(_unicodeRequest);
+    }
+}

test/Microsoft.AspNetCore.Server.Kestrel.Performance/WritableBufferExtensions.cs

@@ -0,0 +1,63 @@
+using System;
+using System.Collections.Generic;
+using System.IO.Pipelines;
+using System.Text;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Performance
+{
+    internal static class WritableBufferExtensions
+    {
+        public static void WriteFast(this WritableBuffer buffer, ReadOnlySpan<byte> source)
+        {
+            if (buffer.Memory.IsEmpty)
+            {
+                buffer.Ensure();
+            }
+
+            // Fast path, try copying to the available memory directly
+            if (source.Length <= buffer.Memory.Length)
+            {
+                source.CopyToFast(buffer.Memory.Span);
+                buffer.Advance(source.Length);
+                return;
+            }
+
+            var remaining = source.Length;
+            var offset = 0;
+
+            while (remaining > 0)
+            {
+                var writable = Math.Min(remaining, buffer.Memory.Length);
+
+                buffer.Ensure(writable);
+
+                if (writable == 0)
+                {
+                    continue;
+                }
+
+                source.Slice(offset, writable).CopyToFast(buffer.Memory.Span);
+
+                remaining -= writable;
+                offset += writable;
+
+                buffer.Advance(writable);
+            }
+        }
+
+        private unsafe static void CopyToFast(this ReadOnlySpan<byte> source, Span<byte> destination)
+        {
+            if (destination.Length < source.Length)
+            {
+                throw new InvalidOperationException();
+            }
+
+            // Assume it fits
+            fixed (byte* pSource = &source.DangerousGetPinnableReference())
+            fixed (byte* pDest = &destination.DangerousGetPinnableReference())
+            {
+                Buffer.MemoryCopy(pSource, pDest, destination.Length, source.Length);
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Server.Kestrel.Performance/configs/CoreConfig.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using BenchmarkDotNet.Configs;
+using BenchmarkDotNet.Diagnosers;
 using BenchmarkDotNet.Engines;
 using BenchmarkDotNet.Jobs;
 using BenchmarkDotNet.Validators;
@@ -13,6 +14,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Performance
         public CoreConfig()
         {
             Add(JitOptimizationsValidator.FailOnError);
+            Add(MemoryDiagnoser.Default);
             Add(new RpsColumn());
 
             Add(Job.Default

test/Microsoft.AspNetCore.Server.KestrelTests/AsciiDecoding.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.Linq;
 using Microsoft.AspNetCore.Server.Kestrel;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
@@ -14,27 +15,16 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         private void FullAsciiRangeSupported()
         {
             var byteRange = Enumerable.Range(1, 127).Select(x => (byte)x).ToArray();
-            using (var pool = new MemoryPool())
+            var s = new Span<byte>(byteRange).GetAsciiStringNonNullCharacters();
+
+            Assert.Equal(s.Length, byteRange.Length);
+
+            for (var i = 1; i < byteRange.Length; i++)
             {
-                var mem = pool.Lease();
+                var sb = (byte)s[i];
-                mem.GetIterator().CopyFrom(byteRange);
+                var b = byteRange[i];
 
-                var begin = mem.GetIterator();
+                Assert.Equal(sb, b);
-                var end = GetIterator(begin, byteRange.Length);
-
-                var s = begin.GetAsciiString(ref end);
-
-                Assert.Equal(s.Length, byteRange.Length);
-
-                for (var i = 1; i < byteRange.Length; i++)
-                {
-                    var sb = (byte)s[i];
-                    var b = byteRange[i];
-
-                    Assert.Equal(sb, b);
-                }
-
-                pool.Return(mem);
             }
         }
 
@@ -49,123 +39,29 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 {
                     var byteRange = Enumerable.Range(1, length).Select(x => (byte)x).ToArray();
                     byteRange[position] = b;
-
+                    
-                    using (var pool = new MemoryPool())
+                    Assert.Throws<InvalidOperationException>(() => new Span<byte>(byteRange).GetAsciiStringNonNullCharacters());
-                    {
-                        var mem = pool.Lease();
-                        mem.GetIterator().CopyFrom(byteRange);
-
-                        var begin = mem.GetIterator();
-                        var end = GetIterator(begin, byteRange.Length);
-
-                        Assert.Throws<BadHttpRequestException>(() => begin.GetAsciiString(ref end));
-
-                        pool.Return(mem);
-                    }
                 }
             }
         }
 
-        [Fact]
-        private void MultiBlockProducesCorrectResults()
-        {
-            var byteRange = Enumerable.Range(0, 512 + 64).Select(x => (byte)((x & 0x7f) | 0x01)).ToArray();
-            var expectedByteRange = byteRange
-                                    .Concat(byteRange)
-                                    .Concat(byteRange)
-                                    .Concat(byteRange)
-                                    .ToArray();
-
-            using (var pool = new MemoryPool())
-            {
-                var mem0 = pool.Lease();
-                var mem1 = pool.Lease();
-                var mem2 = pool.Lease();
-                var mem3 = pool.Lease();
-                mem0.GetIterator().CopyFrom(byteRange);
-                mem1.GetIterator().CopyFrom(byteRange);
-                mem2.GetIterator().CopyFrom(byteRange);
-                mem3.GetIterator().CopyFrom(byteRange);
-
-                mem0.Next = mem1;
-                mem1.Next = mem2;
-                mem2.Next = mem3;
-
-                var begin = mem0.GetIterator();
-                var end = GetIterator(begin, expectedByteRange.Length);
-
-                var s = begin.GetAsciiString(ref end);
-
-                Assert.Equal(s.Length, expectedByteRange.Length);
-
-                for (var i = 0; i < expectedByteRange.Length; i++)
-                {
-                    var sb = (byte)((s[i] & 0x7f) | 0x01);
-                    var b = expectedByteRange[i];
-
-                    Assert.Equal(sb, b);
-                }
-
-                pool.Return(mem0);
-                pool.Return(mem1);
-                pool.Return(mem2);
-                pool.Return(mem3);
-            }
-        }
-
         [Fact]
         private void LargeAllocationProducesCorrectResults()
         {
             var byteRange = Enumerable.Range(0, 16384 + 64).Select(x => (byte)((x & 0x7f) | 0x01)).ToArray();
             var expectedByteRange = byteRange.Concat(byteRange).ToArray();
-            using (var pool = new MemoryPool())
+            
+            var s = new Span<byte>(expectedByteRange).GetAsciiStringNonNullCharacters();
+
+            Assert.Equal(expectedByteRange.Length, s.Length);
+
+            for (var i = 0; i < expectedByteRange.Length; i++)
             {
-                var mem0 = pool.Lease();
+                var sb = (byte)((s[i] & 0x7f) | 0x01);
-                var mem1 = pool.Lease();
+                var b = expectedByteRange[i];
-                mem0.GetIterator().CopyFrom(byteRange);
-                mem1.GetIterator().CopyFrom(byteRange);
 
-                var lastBlock = mem0;
+                Assert.Equal(sb, b);
-                while (lastBlock.Next != null)
-                {
-                    lastBlock = lastBlock.Next;
-                }
-                lastBlock.Next = mem1;
-
-                var begin = mem0.GetIterator();
-                var end = GetIterator(begin, expectedByteRange.Length);
-
-                var s = begin.GetAsciiString(ref end);
-
-                Assert.Equal(expectedByteRange.Length, s.Length);
-
-                for (var i = 0; i < expectedByteRange.Length; i++)
-                {
-                    var sb = (byte)((s[i] & 0x7f) | 0x01);
-                    var b = expectedByteRange[i];
-
-                    Assert.Equal(sb, b);
-                }
-
-                var block = mem0;
-                while (block != null)
-                {
-                    var returnBlock = block;
-                    block = block.Next;
-                    pool.Return(returnBlock);
-                }
             }
         }
-
-        private MemoryPoolIterator GetIterator(MemoryPoolIterator begin, int displacement)
-        {
-            var result = begin;
-            for (int i = 0; i < displacement; ++i)
-            {
-                result.Take();
-            }
-
-            return result;
-        }
     }
 }

test/Microsoft.AspNetCore.Server.KestrelTests/FrameRequestHeadersTests.cs

@@ -304,14 +304,14 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         }
 
         [Fact]
-        public void AppendThrowsWhenHeaderValueContainsNonASCIICharacters()
+        public void AppendThrowsWhenHeaderNameContainsNonASCIICharacters()
         {
             var headers = new FrameRequestHeaders();
             const string key = "\u00141ód\017c";
 
             var encoding = Encoding.GetEncoding("iso-8859-1");
             var exception = Assert.Throws<BadHttpRequestException>(
-                () => headers.Append(encoding.GetBytes(key), key));
+                () => headers.Append(encoding.GetBytes(key), "value"));
             Assert.Equal(StatusCodes.Status400BadRequest, exception.StatusCode);
         }
     }

test/Microsoft.AspNetCore.Server.KestrelTests/FrameTests.cs

@@ -24,7 +24,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 {
     public class FrameTests : IDisposable
     {
-        private readonly IPipe _socketInput;
+        private readonly IPipe _input;
         private readonly TestFrame<object> _frame;
         private readonly ServiceContext _serviceContext;
         private readonly ConnectionContext _connectionContext;
@@ -49,7 +49,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         {
             var trace = new KestrelTrace(new TestKestrelTrace());
             _pipelineFactory = new PipeFactory();
-            _socketInput = _pipelineFactory.Create();
+            _input = _pipelineFactory.Create();
 
             _serviceContext = new ServiceContext
             {
@@ -64,7 +64,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             };
             _connectionContext = new ConnectionContext(listenerContext)
             {
-                Input = _socketInput,
+                Input = _input,
                 Output = new MockSocketOutput(),
                 ConnectionControl = Mock.Of<IConnectionControl>()
             };
@@ -76,130 +76,27 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 
         public void Dispose()
         {
-            _socketInput.Reader.Complete();
+            _input.Reader.Complete();
-            _socketInput.Writer.Complete();
+            _input.Writer.Complete();
             _pipelineFactory.Dispose();
         }
 
-        [Fact]
-        public async Task CanReadHeaderValueWithoutLeadingWhitespace()
-        {
-            _frame.InitializeHeaders();
-
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes("Header:value\r\n\r\n"));
-
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-            var success = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.True(success);
-            Assert.Equal(1, _frame.RequestHeaders.Count);
-            Assert.Equal("value", _frame.RequestHeaders["Header"]);
-            Assert.Equal(readableBuffer.End, _consumed);
-        }
-
-        [Theory]
-        [InlineData("Header: value\r\n\r\n")]
-        [InlineData("Header:  value\r\n\r\n")]
-        [InlineData("Header:\tvalue\r\n\r\n")]
-        [InlineData("Header: \tvalue\r\n\r\n")]
-        [InlineData("Header:\t value\r\n\r\n")]
-        [InlineData("Header:\t\tvalue\r\n\r\n")]
-        [InlineData("Header:\t\t value\r\n\r\n")]
-        [InlineData("Header: \t\tvalue\r\n\r\n")]
-        [InlineData("Header: \t\t value\r\n\r\n")]
-        [InlineData("Header: \t \t value\r\n\r\n")]
-        public async Task LeadingWhitespaceIsNotIncludedInHeaderValue(string rawHeaders)
-        {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeaders));
-
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-            var success = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.True(success);
-            Assert.Equal(1, _frame.RequestHeaders.Count);
-            Assert.Equal("value", _frame.RequestHeaders["Header"]);
-            Assert.Equal(readableBuffer.End, _consumed);
-        }
-
-        [Theory]
-        [InlineData("Header: value \r\n\r\n")]
-        [InlineData("Header: value\t\r\n\r\n")]
-        [InlineData("Header: value \t\r\n\r\n")]
-        [InlineData("Header: value\t \r\n\r\n")]
-        [InlineData("Header: value\t\t\r\n\r\n")]
-        [InlineData("Header: value\t\t \r\n\r\n")]
-        [InlineData("Header: value \t\t\r\n\r\n")]
-        [InlineData("Header: value \t\t \r\n\r\n")]
-        [InlineData("Header: value \t \t \r\n\r\n")]
-        public async Task TrailingWhitespaceIsNotIncludedInHeaderValue(string rawHeaders)
-        {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeaders));
-
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-            var success = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.True(success);
-            Assert.Equal(1, _frame.RequestHeaders.Count);
-            Assert.Equal("value", _frame.RequestHeaders["Header"]);
-            Assert.Equal(readableBuffer.End, _consumed);
-        }
-
-        [Theory]
-        [InlineData("Header: one two three\r\n\r\n", "one two three")]
-        [InlineData("Header: one  two  three\r\n\r\n", "one  two  three")]
-        [InlineData("Header: one\ttwo\tthree\r\n\r\n", "one\ttwo\tthree")]
-        [InlineData("Header: one two\tthree\r\n\r\n", "one two\tthree")]
-        [InlineData("Header: one\ttwo three\r\n\r\n", "one\ttwo three")]
-        [InlineData("Header: one \ttwo \tthree\r\n\r\n", "one \ttwo \tthree")]
-        [InlineData("Header: one\t two\t three\r\n\r\n", "one\t two\t three")]
-        [InlineData("Header: one \ttwo\t three\r\n\r\n", "one \ttwo\t three")]
-        public async Task WhitespaceWithinHeaderValueIsPreserved(string rawHeaders, string expectedValue)
-        {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeaders));
-
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-            var success = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.True(success);
-            Assert.Equal(1, _frame.RequestHeaders.Count);
-            Assert.Equal(expectedValue, _frame.RequestHeaders["Header"]);
-            Assert.Equal(readableBuffer.End, _consumed);
-        }
-
-        [Theory]
-        [MemberData(nameof(InvalidRequestHeaderData))]
-        public async Task TakeMessageHeadersThrowsOnInvalidRequestHeaders(string rawHeaders, string expectedExceptionMessage)
-        {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeaders));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-
-            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.Equal(expectedExceptionMessage, exception.Message);
-            Assert.Equal(StatusCodes.Status400BadRequest, exception.StatusCode);
-        }
-
         [Fact]
         public async Task TakeMessageHeadersThrowsOnHeaderValueWithLineFolding_CharacterNotAvailableOnFirstAttempt()
         {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes("Header-1: value1\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes("Header-1: value1\r\n"));
 
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
-            Assert.False(_frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined));
+            Assert.False(_frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(" "));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes(" "));
 
-            readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
-            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined));
+            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
-            Assert.Equal("Header value line folding not supported.", exception.Message);
+            Assert.Equal("Whitespace is not allowed in header name.", exception.Message);
             Assert.Equal(StatusCodes.Status400BadRequest, exception.StatusCode);
         }
 
@@ -210,11 +107,11 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             _serviceContext.ServerOptions.Limits.MaxRequestHeadersTotalSize = headerLine.Length - 1;
             _frame.Reset();
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine}\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine}\r\n"));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined));
+            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.Equal("Request headers too long.", exception.Message);
             Assert.Equal(StatusCodes.Status431RequestHeaderFieldsTooLarge, exception.StatusCode);
@@ -226,36 +123,16 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             const string headerLines = "Header-1: value1\r\nHeader-2: value2\r\n";
             _serviceContext.ServerOptions.Limits.MaxRequestHeaderCount = 1;
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLines}\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLines}\r\n"));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined));
+            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.Equal("Request contains too many headers.", exception.Message);
             Assert.Equal(StatusCodes.Status431RequestHeaderFieldsTooLarge, exception.StatusCode);
         }
 
-        [Theory]
-        [InlineData("Cookie: \r\n\r\n", 1)]
-        [InlineData("Cookie:\r\n\r\n", 1)]
-        [InlineData("Cookie: \r\nConnection: close\r\n\r\n", 2)]
-        [InlineData("Cookie:\r\nConnection: close\r\n\r\n", 2)]
-        [InlineData("Connection: close\r\nCookie: \r\n\r\n", 2)]
-        [InlineData("Connection: close\r\nCookie:\r\n\r\n", 2)]
-        public async Task EmptyHeaderValuesCanBeParsed(string rawHeaders, int numHeaders)
-        {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeaders));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-
-            var success = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.True(success);
-            Assert.Equal(numHeaders, _frame.RequestHeaders.Count);
-            Assert.Equal(readableBuffer.End, _consumed);
-        }
-
         [Fact]
         public void ResetResetsScheme()
         {
@@ -279,11 +156,11 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             options.Limits.MaxRequestHeaderCount = 1;
             _serviceContext.ServerOptions = options;
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine1}\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine1}\r\n"));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            var takeMessageHeaders = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
+            var takeMessageHeaders = _frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.True(takeMessageHeaders);
             Assert.Equal(1, _frame.RequestHeaders.Count);
@@ -291,11 +168,11 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 
             _frame.Reset();
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine2}\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes($"{headerLine2}\r\n"));
-            readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            takeMessageHeaders = _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
+            takeMessageHeaders = _frame.TakeMessageHeaders(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.True(takeMessageHeaders);
             Assert.Equal(1, _frame.RequestHeaders.Count);
@@ -390,86 +267,37 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         public async Task TakeStartLineSetsFrameProperties(
             string requestLine,
             string expectedMethod,
-            string expectedPath,
+            string expectedRawTarget,
+            string expectedRawPath,
+            string expectedDecodedPath,
             string expectedQueryString,
             string expectedHttpVersion)
         {
             var requestLineBytes = Encoding.ASCII.GetBytes(requestLine);
-            await _socketInput.Writer.WriteAsync(requestLineBytes);
+            await _input.Writer.WriteAsync(requestLineBytes);
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
             var returnValue = _frame.TakeStartLine(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.True(returnValue);
             Assert.Equal(expectedMethod, _frame.Method);
-            Assert.Equal(expectedPath, _frame.Path);
+            Assert.Equal(expectedRawTarget, _frame.RawTarget);
+            Assert.Equal(expectedDecodedPath, _frame.Path);
             Assert.Equal(expectedQueryString, _frame.QueryString);
             Assert.Equal(expectedHttpVersion, _frame.HttpVersion);
         }
 
         [Fact]
-        public async Task TakeStartLineCallsConsumingCompleteWithFurthestExamined()
+        public async Task ParseRequestStartsRequestHeadersTimeoutOnFirstByteAvailable()
-        {
-            var requestLineBytes = Encoding.ASCII.GetBytes("GET / ");
-            await _socketInput.Writer.WriteAsync(requestLineBytes);
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-
-            _frame.TakeStartLine(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.Equal(readableBuffer.Start, _consumed);
-            Assert.Equal(readableBuffer.End, _examined);
-
-            requestLineBytes = Encoding.ASCII.GetBytes("HTTP/1.1\r\n");
-            await _socketInput.Writer.WriteAsync(requestLineBytes);
-            readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-
-            _frame.TakeStartLine(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.Equal(readableBuffer.End, _consumed);
-            Assert.Equal(readableBuffer.End, _examined);
-        }
-
-        [Theory]
-        [InlineData("G")]
-        [InlineData("GE")]
-        [InlineData("GET")]
-        [InlineData("GET ")]
-        [InlineData("GET /")]
-        [InlineData("GET / ")]
-        [InlineData("GET / H")]
-        [InlineData("GET / HT")]
-        [InlineData("GET / HTT")]
-        [InlineData("GET / HTTP")]
-        [InlineData("GET / HTTP/")]
-        [InlineData("GET / HTTP/1")]
-        [InlineData("GET / HTTP/1.")]
-        [InlineData("GET / HTTP/1.1")]
-        [InlineData("GET / HTTP/1.1\r")]
-        public async Task TakeStartLineReturnsWhenGivenIncompleteRequestLines(string requestLine)
-        {
-            var requestLineBytes = Encoding.ASCII.GetBytes(requestLine);
-            await _socketInput.Writer.WriteAsync(requestLineBytes);
-
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-            var returnValue = _frame.TakeStartLine(readableBuffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.False(returnValue);
-        }
-
-        [Fact]
-        public async Task TakeStartLineStartsRequestHeadersTimeoutOnFirstByteAvailable()
         {
             var connectionControl = new Mock<IConnectionControl>();
             _connectionContext.ConnectionControl = connectionControl.Object;
 
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes("G"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes("G"));
 
-            _frame.TakeStartLine((await _socketInput.Reader.ReadAsync()).Buffer, out _consumed, out _examined);
+            _frame.ParseRequest((await _input.Reader.ReadAsync()).Buffer, out _consumed, out _examined);
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             var expectedRequestHeadersTimeout = (long)_serviceContext.ServerOptions.Limits.RequestHeadersTimeout.TotalMilliseconds;
             connectionControl.Verify(cc => cc.ResetTimeout(expectedRequestHeadersTimeout, TimeoutAction.SendTimeoutResponse));
@@ -481,93 +309,42 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             _serviceContext.ServerOptions.Limits.MaxRequestLineSize = "GET / HTTP/1.1\r\n".Length;
 
             var requestLineBytes = Encoding.ASCII.GetBytes("GET /a HTTP/1.1\r\n");
-            await _socketInput.Writer.WriteAsync(requestLineBytes);
+            await _input.Writer.WriteAsync(requestLineBytes);
 
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
             var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeStartLine(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
             Assert.Equal("Request line too long.", exception.Message);
             Assert.Equal(StatusCodes.Status414UriTooLong, exception.StatusCode);
         }
 
         [Theory]
-        [MemberData(nameof(InvalidRequestLineData))]
+        [MemberData(nameof(RequestLineWithEncodedNullCharInTargetData))]
-        public async Task TakeStartLineThrowsOnInvalidRequestLine(string requestLine, Type expectedExceptionType, string expectedExceptionMessage)
+        public async Task TakeStartLineThrowsOnEncodedNullCharInTarget(string requestLine)
         {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(requestLine));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes(requestLine));
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            var exception = Assert.Throws(expectedExceptionType, () =>
+            var exception = Assert.Throws<InvalidOperationException>(() =>
                 _frame.TakeStartLine(readableBuffer, out _consumed, out _examined));
-            _socketInput.Reader.Advance(_consumed, _examined);
+            _input.Reader.Advance(_consumed, _examined);
 
-            Assert.Equal(expectedExceptionMessage, exception.Message);
+            Assert.Equal("The path contains null characters.", exception.Message);
-
-            if (expectedExceptionType == typeof(BadHttpRequestException))
-            {
-                Assert.Equal(StatusCodes.Status400BadRequest, (exception as BadHttpRequestException).StatusCode);
-            }
         }
 
         [Theory]
-        [MemberData(nameof(UnrecognizedHttpVersionData))]
+        [MemberData(nameof(RequestLineWithNullCharInTargetData))]
-        public async Task TakeStartLineThrowsOnUnrecognizedHttpVersion(string httpVersion)
+        public async Task TakeStartLineThrowsOnNullCharInTarget(string requestLine)
         {
-            await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes($"GET / {httpVersion}\r\n"));
+            await _input.Writer.WriteAsync(Encoding.ASCII.GetBytes(requestLine));
+            var readableBuffer = (await _input.Reader.ReadAsync()).Buffer;
 
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
+            var exception = Assert.Throws<InvalidOperationException>(() =>
+                _frame.TakeStartLine(readableBuffer, out _consumed, out _examined));
+            _input.Reader.Advance(_consumed, _examined);
 
-            var exception = Assert.Throws<BadHttpRequestException>(() => _frame.TakeStartLine(readableBuffer, out _consumed, out _examined));
+            Assert.Equal(new InvalidOperationException().Message, exception.Message);
-            _socketInput.Reader.Advance(_consumed, _examined);
-
-            Assert.Equal($"Unrecognized HTTP version: {httpVersion}", exception.Message);
-            Assert.Equal(StatusCodes.Status505HttpVersionNotsupported, exception.StatusCode);
-        }
-
-        [Fact]
-        public async Task TakeMessageHeadersCallsConsumingCompleteWithFurthestExamined()
-        {
-            foreach (var rawHeader in new[] { "Header: ", "value\r\n", "\r\n" })
-            {
-                await _socketInput.Writer.WriteAsync(Encoding.ASCII.GetBytes(rawHeader));
-
-                var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-                _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out _consumed, out _examined);
-                _socketInput.Reader.Advance(_consumed, _examined);
-                Assert.Equal(readableBuffer.End, _examined);
-            }
-        }
-
-        [Theory]
-        [InlineData("\r")]
-        [InlineData("H")]
-        [InlineData("He")]
-        [InlineData("Hea")]
-        [InlineData("Head")]
-        [InlineData("Heade")]
-        [InlineData("Header")]
-        [InlineData("Header:")]
-        [InlineData("Header: ")]
-        [InlineData("Header: v")]
-        [InlineData("Header: va")]
-        [InlineData("Header: val")]
-        [InlineData("Header: valu")]
-        [InlineData("Header: value")]
-        [InlineData("Header: value\r")]
-        [InlineData("Header: value\r\n")]
-        [InlineData("Header: value\r\n\r")]
-        public async Task TakeMessageHeadersReturnsWhenGivenIncompleteHeaders(string headers)
-        {
-            var headerBytes = Encoding.ASCII.GetBytes(headers);
-            await _socketInput.Writer.WriteAsync(headerBytes);
-
-            ReadCursor consumed;
-            ReadCursor examined;
-            var readableBuffer = (await _socketInput.Reader.ReadAsync()).Buffer;
-
-            Assert.Equal(false, _frame.TakeMessageHeaders(readableBuffer, (FrameRequestHeaders)_frame.RequestHeaders, out consumed, out examined));
-            _socketInput.Reader.Advance(consumed, examined);
         }
 
         [Fact]
@@ -582,7 +359,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             connectionControl.Verify(cc => cc.SetTimeout(expectedKeepAliveTimeout, TimeoutAction.CloseConnection));
 
             _frame.StopAsync();
-            _socketInput.Writer.Complete();
+            _input.Writer.Complete();
 
             requestProcessingTask.Wait();
         }
@@ -664,13 +441,13 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             _frame.Start();
 
             var data = Encoding.ASCII.GetBytes("GET / HTTP/1.1\r\n\r\n");
-            await _socketInput.Writer.WriteAsync(data);
+            await _input.Writer.WriteAsync(data);
 
             var requestProcessingTask = _frame.StopAsync();
             Assert.IsNotType(typeof(Task<Task>), requestProcessingTask);
 
             await requestProcessingTask.TimeoutAfter(TimeSpan.FromSeconds(10));
-            _socketInput.Writer.Complete();
+            _input.Writer.Complete();
         }
 
         [Fact]
@@ -741,12 +518,36 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             Assert.NotSame(original, _frame.RequestAborted.WaitHandle);
         }
 
-        public static IEnumerable<object> ValidRequestLineData => HttpParsingData.ValidRequestLineData;
+        public static IEnumerable<object> ValidRequestLineData => HttpParsingData.RequestLineValidData;
 
-        public static IEnumerable<object> InvalidRequestLineData => HttpParsingData.InvalidRequestLineData;
+        public static TheoryData<string> RequestLineWithEncodedNullCharInTargetData
+        {
+            get
+            {
+                var data = new TheoryData<string>();
 
-        public static TheoryData<string> UnrecognizedHttpVersionData => HttpParsingData.UnrecognizedHttpVersionData;
+                foreach (var requestLine in HttpParsingData.RequestLineWithEncodedNullCharInTargetData)
+                {
+                    data.Add(requestLine);
+                }
 
-        public static IEnumerable<object[]> InvalidRequestHeaderData => HttpParsingData.InvalidRequestHeaderData;
+                return data;
+            }
+        }
+
+        public static TheoryData<string> RequestLineWithNullCharInTargetData
+        {
+            get
+            {
+                var data = new TheoryData<string>();
+
+                foreach (var requestLine in HttpParsingData.RequestLineWithNullCharInTargetData)
+                {
+                    data.Add(requestLine);
+                }
+
+                return data;
+            }
+        }
     }
 }

test/Microsoft.AspNetCore.Server.KestrelTests/HttpParserTests.cs

@@ -0,0 +1,383 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.IO.Pipelines;
+using System.Linq;
+using System.Text;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Server.Kestrel;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
+using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
+using Microsoft.AspNetCore.Testing;
+using Microsoft.Extensions.Logging;
+using Moq;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Server.KestrelTests
+{
+    public class HttpParserTests
+    {
+        // Returns true when all headers parsed
+        // Return false otherwise
+
+        [Theory]
+        [MemberData(nameof(RequestLineValidData))]
+        public void ParsesRequestLine(
+            string requestLine,
+            string expectedMethod,
+            string expectedRawTarget,
+            string expectedRawPath,
+            string expectedDecodedPath,
+            string expectedQueryString,
+            string expectedVersion)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+
+            string parsedMethod = null;
+            string parsedVersion = null;
+            string parsedRawTarget = null;
+            string parsedRawPath = null;
+            string parsedQuery = null;
+            var requestLineHandler = new Mock<IHttpRequestLineHandler>();
+            requestLineHandler
+                .Setup(handler => handler.OnStartLine(
+                    It.IsAny<HttpMethod>(),
+                    It.IsAny<HttpVersion>(),
+                    It.IsAny<Span<byte>>(),
+                    It.IsAny<Span<byte>>(),
+                    It.IsAny<Span<byte>>(),
+                    It.IsAny<Span<byte>>()))
+                .Callback<HttpMethod, HttpVersion, Span<byte>, Span<byte>, Span<byte>, Span<byte>>((method, version, target, path, query, customMethod) =>
+                {
+                    parsedMethod = method != HttpMethod.Custom ? HttpUtilities.MethodToString(method) : customMethod.GetAsciiStringNonNullCharacters();
+                    parsedVersion = HttpUtilities.VersionToString(version);
+                    parsedRawTarget = target.GetAsciiStringNonNullCharacters();
+                    parsedRawPath = path.GetAsciiStringNonNullCharacters();
+                    parsedQuery = query.GetAsciiStringNonNullCharacters();
+                });
+
+            Assert.True(parser.ParseRequestLine(requestLineHandler.Object, buffer, out var consumed, out var examined));
+
+            Assert.Equal(parsedMethod, expectedMethod);
+            Assert.Equal(parsedVersion, expectedVersion);
+            Assert.Equal(parsedRawTarget, expectedRawTarget);
+            Assert.Equal(parsedRawPath, expectedRawPath);
+            Assert.Equal(parsedVersion, expectedVersion);
+            Assert.Equal(buffer.End, consumed);
+            Assert.Equal(buffer.End, examined);
+        }
+
+        [Theory]
+        [MemberData(nameof(RequestLineIncompleteData))]
+        public void ParseRequestLineReturnsFalseWhenGivenIncompleteRequestLines(string requestLine)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+
+            Assert.False(parser.ParseRequestLine(Mock.Of<IHttpRequestLineHandler>(), buffer, out var consumed, out var examined));
+        }
+
+        [Theory]
+        [MemberData(nameof(RequestLineIncompleteData))]
+        public void ParseRequestLineDoesNotConsumeIncompleteRequestLine(string requestLine)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+
+            Assert.False(parser.ParseRequestLine(Mock.Of<IHttpRequestLineHandler>(), buffer, out var consumed, out var examined));
+
+            Assert.Equal(buffer.Start, consumed);
+            Assert.Equal(buffer.End, examined);
+        }
+
+        [Theory]
+        [MemberData(nameof(RequestLineInvalidData))]
+        public void ParseRequestLineThrowsOnInvalidRequestLine(string requestLine)
+        {
+            var mockTrace = new Mock<IKestrelTrace>();
+            mockTrace
+                .Setup(trace => trace.IsEnabled(LogLevel.Information))
+                .Returns(true);
+
+            var parser = CreateParser(mockTrace.Object);
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+
+            var exception = Assert.Throws<BadHttpRequestException>(() =>
+                parser.ParseRequestLine(Mock.Of<IHttpRequestLineHandler>(), buffer, out var consumed, out var examined));
+
+            Assert.Equal($"Invalid request line: {requestLine.Replace("\r", "<0x0D>").Replace("\n", "<0x0A>")}", exception.Message);
+            Assert.Equal(StatusCodes.Status400BadRequest, (exception as BadHttpRequestException).StatusCode);
+        }
+
+        [Theory]
+        [MemberData(nameof(UnrecognizedHttpVersionData))]
+        public void ParseRequestLineThrowsOnUnrecognizedHttpVersion(string httpVersion)
+        {
+            var requestLine = $"GET / {httpVersion}\r\n";
+
+            var mockTrace = new Mock<IKestrelTrace>();
+            mockTrace
+                .Setup(trace => trace.IsEnabled(LogLevel.Information))
+                .Returns(true);
+
+            var parser = CreateParser(mockTrace.Object);
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(requestLine));
+
+            var exception = Assert.Throws<BadHttpRequestException>(() =>
+                parser.ParseRequestLine(Mock.Of<IHttpRequestLineHandler>(), buffer, out var consumed, out var examined));
+
+            Assert.Equal($"Unrecognized HTTP version: {httpVersion}", exception.Message);
+            Assert.Equal(StatusCodes.Status505HttpVersionNotsupported, (exception as BadHttpRequestException).StatusCode);
+        }
+
+        [Theory]
+        [InlineData("\r")]
+        [InlineData("H")]
+        [InlineData("He")]
+        [InlineData("Hea")]
+        [InlineData("Head")]
+        [InlineData("Heade")]
+        [InlineData("Header")]
+        [InlineData("Header:")]
+        [InlineData("Header: ")]
+        [InlineData("Header: v")]
+        [InlineData("Header: va")]
+        [InlineData("Header: val")]
+        [InlineData("Header: valu")]
+        [InlineData("Header: value")]
+        [InlineData("Header: value\r")]
+        [InlineData("Header: value\r\n")]
+        [InlineData("Header: value\r\n\r")]
+        [InlineData("Header-1: value1\r\nH")]
+        [InlineData("Header-1: value1\r\nHe")]
+        [InlineData("Header-1: value1\r\nHea")]
+        [InlineData("Header-1: value1\r\nHead")]
+        [InlineData("Header-1: value1\r\nHeade")]
+        [InlineData("Header-1: value1\r\nHeader")]
+        [InlineData("Header-1: value1\r\nHeader-")]
+        [InlineData("Header-1: value1\r\nHeader-2")]
+        [InlineData("Header-1: value1\r\nHeader-2:")]
+        [InlineData("Header-1: value1\r\nHeader-2: ")]
+        [InlineData("Header-1: value1\r\nHeader-2: v")]
+        [InlineData("Header-1: value1\r\nHeader-2: va")]
+        [InlineData("Header-1: value1\r\nHeader-2: val")]
+        [InlineData("Header-1: value1\r\nHeader-2: valu")]
+        [InlineData("Header-1: value1\r\nHeader-2: value")]
+        [InlineData("Header-1: value1\r\nHeader-2: value2")]
+        [InlineData("Header-1: value1\r\nHeader-2: value2\r")]
+        [InlineData("Header-1: value1\r\nHeader-2: value2\r\n")]
+        [InlineData("Header-1: value1\r\nHeader-2: value2\r\n\r")]
+        public void ParseHeadersReturnsFalseWhenGivenIncompleteHeaders(string rawHeaders)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            Assert.False(parser.ParseHeaders(Mock.Of<IHttpHeadersHandler>(), buffer, out var consumed, out var examined, out var consumedBytes));
+        }
+
+        [Theory]
+        [InlineData("\r")]
+        [InlineData("H")]
+        [InlineData("He")]
+        [InlineData("Hea")]
+        [InlineData("Head")]
+        [InlineData("Heade")]
+        [InlineData("Header")]
+        [InlineData("Header:")]
+        [InlineData("Header: ")]
+        [InlineData("Header: v")]
+        [InlineData("Header: va")]
+        [InlineData("Header: val")]
+        [InlineData("Header: valu")]
+        [InlineData("Header: value")]
+        [InlineData("Header: value\r")]
+        public void ParseHeadersDoesNotConsumeIncompleteHeader(string rawHeaders)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+            parser.ParseHeaders(Mock.Of<IHttpHeadersHandler>(), buffer, out var consumed, out var examined, out var consumedBytes);
+
+            Assert.Equal(buffer.Start, consumed);
+            Assert.Equal(buffer.End, examined);
+            Assert.Equal(0, consumedBytes);
+        }
+
+        [Fact]
+        public void ParseHeadersCanReadHeaderValueWithoutLeadingWhitespace()
+        {
+            VerifyHeader("Header", "value", "value");
+        }
+
+        [Theory]
+        [InlineData("Cookie: \r\n\r\n", "Cookie", "", null, null)]
+        [InlineData("Cookie:\r\n\r\n", "Cookie", "", null, null)]
+        [InlineData("Cookie: \r\nConnection: close\r\n\r\n", "Cookie", "", "Connection", "close")]
+        [InlineData("Cookie:\r\nConnection: close\r\n\r\n", "Cookie", "", "Connection", "close")]
+        [InlineData("Connection: close\r\nCookie: \r\n\r\n", "Connection", "close", "Cookie", "")]
+        [InlineData("Connection: close\r\nCookie:\r\n\r\n", "Connection", "close", "Cookie", "")]
+        public void ParseHeadersCanParseEmptyHeaderValues(
+            string rawHeaders,
+            string expectedHeaderName1,
+            string expectedHeaderValue1,
+            string expectedHeaderName2,
+            string expectedHeaderValue2)
+        {
+            var expectedHeaderNames = expectedHeaderName2 == null
+                ? new[] { expectedHeaderName1 }
+                : new[] { expectedHeaderName1, expectedHeaderName2 };
+            var expectedHeaderValues = expectedHeaderValue2 == null
+                ? new[] { expectedHeaderValue1 }
+                : new[] { expectedHeaderValue1, expectedHeaderValue2 };
+
+            VerifyRawHeaders(rawHeaders, expectedHeaderNames, expectedHeaderValues);
+        }
+
+        [Theory]
+        [InlineData(" value")]
+        [InlineData("  value")]
+        [InlineData("\tvalue")]
+        [InlineData(" \tvalue")]
+        [InlineData("\t value")]
+        [InlineData("\t\tvalue")]
+        [InlineData("\t\t value")]
+        [InlineData(" \t\tvalue")]
+        [InlineData(" \t\t value")]
+        [InlineData(" \t \t value")]
+        public void ParseHeadersDoesNotIncludeLeadingWhitespaceInHeaderValue(string rawHeaderValue)
+        {
+            VerifyHeader("Header", rawHeaderValue, "value");
+        }
+
+        [Theory]
+        [InlineData("value ")]
+        [InlineData("value\t")]
+        [InlineData("value \t")]
+        [InlineData("value\t ")]
+        [InlineData("value\t\t")]
+        [InlineData("value\t\t ")]
+        [InlineData("value \t\t")]
+        [InlineData("value \t\t ")]
+        [InlineData("value \t \t ")]
+        public void ParseHeadersDoesNotIncludeTrailingWhitespaceInHeaderValue(string rawHeaderValue)
+        {
+            VerifyHeader("Header", rawHeaderValue, "value");
+        }
+
+        [Theory]
+        [InlineData("one two three")]
+        [InlineData("one  two  three")]
+        [InlineData("one\ttwo\tthree")]
+        [InlineData("one two\tthree")]
+        [InlineData("one\ttwo three")]
+        [InlineData("one \ttwo \tthree")]
+        [InlineData("one\t two\t three")]
+        [InlineData("one \ttwo\t three")]
+        public void ParseHeadersPreservesWhitespaceWithinHeaderValue(string headerValue)
+        {
+            VerifyHeader("Header", headerValue, headerValue);
+        }
+
+        [Fact]
+        public void ParseHeadersConsumesBytesCorrectlyAtEnd()
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+
+            const string headerLine = "Header: value\r\n\r";
+            var buffer1 = ReadableBuffer.Create(Encoding.ASCII.GetBytes(headerLine));
+            Assert.False(parser.ParseHeaders(Mock.Of<IHttpHeadersHandler>(), buffer1, out var consumed, out var examined, out var consumedBytes));
+
+            Assert.Equal(buffer1.Move(buffer1.Start, headerLine.Length - 1), consumed);
+            Assert.Equal(buffer1.End, examined);
+            Assert.Equal(headerLine.Length - 1, consumedBytes);
+
+            var buffer2 = ReadableBuffer.Create(Encoding.ASCII.GetBytes("\r\n"));
+            Assert.True(parser.ParseHeaders(Mock.Of<IHttpHeadersHandler>(), buffer2, out consumed, out examined, out consumedBytes));
+
+            Assert.Equal(buffer2.End, consumed);
+            Assert.Equal(buffer2.End, examined);
+            Assert.Equal(2, consumedBytes);
+        }
+
+        [Theory]
+        [MemberData(nameof(RequestHeaderInvalidData))]
+        public void ParseHeadersThrowsOnInvalidRequestHeaders(string rawHeaders, string expectedExceptionMessage)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+
+            var exception = Assert.Throws<BadHttpRequestException>(() =>
+                parser.ParseHeaders(Mock.Of<IHttpHeadersHandler>(), buffer, out var consumed, out var examined, out var consumedBytes));
+
+            Assert.Equal(expectedExceptionMessage, exception.Message);
+            Assert.Equal(StatusCodes.Status400BadRequest, exception.StatusCode);
+        }
+
+        private void VerifyHeader(
+            string headerName,
+            string rawHeaderValue,
+            string expectedHeaderValue)
+        {
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes($"{headerName}:{rawHeaderValue}\r\n"));
+
+            string parsedHeaderName = "unexpected";
+            string parsedHeaderValue = "unexpected";
+            var headersHandler = new Mock<IHttpHeadersHandler>();
+            headersHandler
+                .Setup(handler => handler.OnHeader(It.IsAny<Span<byte>>(), It.IsAny<Span<byte>>()))
+                .Callback<Span<byte>, Span<byte>>((name, value) =>
+                {
+                    parsedHeaderName = name.GetAsciiStringNonNullCharacters();
+                    parsedHeaderValue = value.GetAsciiStringNonNullCharacters();
+                });
+
+            parser.ParseHeaders(headersHandler.Object, buffer, out var consumed, out var examined, out var consumedBytes);
+
+            Assert.Equal(headerName, parsedHeaderName);
+            Assert.Equal(expectedHeaderValue, parsedHeaderValue);
+            Assert.Equal(buffer.End, consumed);
+            Assert.Equal(buffer.End, examined);
+        }
+
+        private void VerifyRawHeaders(string rawHeaders, IEnumerable<string> expectedHeaderNames, IEnumerable<string> expectedHeaderValues)
+        {
+            Assert.True(expectedHeaderNames.Count() == expectedHeaderValues.Count(), $"{nameof(expectedHeaderNames)} and {nameof(expectedHeaderValues)} sizes must match");
+
+            var parser = CreateParser(Mock.Of<IKestrelTrace>());
+            var buffer = ReadableBuffer.Create(Encoding.ASCII.GetBytes(rawHeaders));
+
+            var parsedHeaders = new List<Tuple<string, string>>();
+            var headersHandler = new Mock<IHttpHeadersHandler>();
+            headersHandler
+                .Setup(handler => handler.OnHeader(It.IsAny<Span<byte>>(), It.IsAny<Span<byte>>()))
+                .Callback<Span<byte>, Span<byte>>((name, value) =>
+                {
+                    parsedHeaders.Add(Tuple.Create(name.GetAsciiStringNonNullCharacters(), value.GetAsciiStringNonNullCharacters()));
+                });
+
+            parser.ParseHeaders(headersHandler.Object, buffer, out var consumed, out var examined, out var consumedBytes);
+
+            Assert.Equal(expectedHeaderNames.Count(), parsedHeaders.Count);
+            Assert.Equal(expectedHeaderNames, parsedHeaders.Select(t => t.Item1));
+            Assert.Equal(expectedHeaderValues, parsedHeaders.Select(t => t.Item2));
+            Assert.Equal(buffer.End, consumed);
+            Assert.Equal(buffer.End, examined);
+        }
+
+        private IHttpParser CreateParser(IKestrelTrace log) => new KestrelHttpParser(log);
+
+        public static IEnumerable<string[]> RequestLineValidData => HttpParsingData.RequestLineValidData;
+
+        public static IEnumerable<object[]> RequestLineIncompleteData => HttpParsingData.RequestLineIncompleteData.Select(requestLine => new[] { requestLine });
+
+        public static IEnumerable<object[]> RequestLineInvalidData => HttpParsingData.RequestLineInvalidData.Select(requestLine => new[] { requestLine });
+
+        public static TheoryData<string> UnrecognizedHttpVersionData => HttpParsingData.UnrecognizedHttpVersionData;
+
+        public static IEnumerable<object[]> RequestHeaderInvalidData => HttpParsingData.RequestHeaderInvalidData;
+    }
+}

test/Microsoft.AspNetCore.Server.KestrelTests/MemoryPoolBlockTests.cs

@@ -8,105 +8,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 {
     public class MemoryPoolBlockTests
     {
-        [Fact]
+      
-        public void SeekWorks()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var block = pool.Lease();
-                foreach (var ch in Enumerable.Range(0, 256).Select(x => (byte)x))
-                {
-                    block.Array[block.End++] = ch;
-                }
-
-                var iterator = block.GetIterator();
-                foreach (var ch in Enumerable.Range(0, 256).Select(x => (byte)x))
-                {
-                    var hit = iterator;
-                    hit.Seek(ch);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(ch, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(byte.MaxValue, ch);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(ch, byte.MaxValue, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(byte.MaxValue, ch, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(ch, byte.MaxValue, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-                }
-
-                pool.Return(block);
-            }
-        }
-
-        [Fact]
-        public void SeekWorksAcrossBlocks()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var block1 = pool.Lease();
-                var block2 = block1.Next = pool.Lease();
-                var block3 = block2.Next = pool.Lease();
-
-                foreach (var ch in Enumerable.Range(0, 34).Select(x => (byte)x))
-                {
-                    block1.Array[block1.End++] = ch;
-                }
-                foreach (var ch in Enumerable.Range(34, 25).Select(x => (byte)x))
-                {
-                    block2.Array[block2.End++] = ch;
-                }
-                foreach (var ch in Enumerable.Range(59, 197).Select(x => (byte)x))
-                {
-                    block3.Array[block3.End++] = ch;
-                }
-
-                var iterator = block1.GetIterator();
-                foreach (var ch in Enumerable.Range(0, 256).Select(x => (byte)x))
-                {
-                    var hit = iterator;
-                    hit.Seek(ch);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(ch, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(byte.MaxValue, ch);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(ch, byte.MaxValue, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(byte.MaxValue, ch, byte.MaxValue);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-
-                    hit = iterator;
-                    hit.Seek(byte.MaxValue, byte.MaxValue, ch);
-                    Assert.Equal(ch, iterator.GetLength(hit));
-                }
-
-                pool.Return(block1);
-                pool.Return(block2);
-                pool.Return(block3);
-            }
-        }
-
         [Fact]
         public void GetLengthBetweenIteratorsWorks()
         {
@@ -192,87 +94,7 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 pool.Return(block2);
             }
         }
-
+        
-        [Fact]
-        public void CopyToCorrectlyTraversesBlocks()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var block1 = pool.Lease();
-                var block2 = block1.Next = pool.Lease();
-
-                for (int i = 0; i < 128; i++)
-                {
-                    block1.Array[block1.End++] = (byte)i;
-                }
-                for (int i = 128; i < 256; i++)
-                {
-                    block2.Array[block2.End++] = (byte)i;
-                }
-
-                var beginIterator = block1.GetIterator();
-                
-                var array = new byte[256];
-                int actual;
-                var endIterator = beginIterator.CopyTo(array, 0, 256, out actual);
-
-                Assert.Equal(256, actual);
-
-                for (int i = 0; i < 256; i++)
-                {
-                    Assert.Equal(i, array[i]);
-                }
-
-                endIterator.CopyTo(array, 0, 256, out actual);
-                Assert.Equal(0, actual);
-
-                pool.Return(block1);
-                pool.Return(block2);
-            }
-        }
-
-        [Fact]
-        public void CopyFromCorrectlyTraversesBlocks()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var block1 = pool.Lease();
-                var start = block1.GetIterator();
-                var end = start;
-                var bufferSize = block1.Data.Count * 3;
-                var buffer = new byte[bufferSize];
-
-                for (int i = 0; i < bufferSize; i++)
-                {
-                    buffer[i] = (byte)(i % 73);
-                }
-
-                Assert.Null(block1.Next);
-
-                end.CopyFrom(new ArraySegment<byte>(buffer));
-
-                Assert.NotNull(block1.Next);
-
-                for (int i = 0; i < bufferSize; i++)
-                {
-                    Assert.Equal(i % 73, start.Take());
-                }
-
-                Assert.Equal(-1, start.Take());
-                Assert.Equal(start.Block, end.Block);
-                Assert.Equal(start.Index, end.Index);
-
-                var block = block1;
-                while (block != null)
-                {
-                    var returnBlock = block;
-                    block = block.Next;
-
-                    pool.Return(returnBlock);
-                }
-            }
-        }
-
         [Fact]
         public void IsEndCorrectlyTraversesBlocks()
         {

test/Microsoft.AspNetCore.Server.KestrelTests/MemoryPoolExtensions.cs

@@ -6,8 +6,11 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
     {
         public static MemoryPoolIterator Add(this MemoryPoolIterator iterator, int count)
         {
-            int actual;
+            for (int i = 0; i < count; i++)
-            return iterator.CopyTo(new byte[count], 0, count,  out actual);
+            {
+                iterator.Take();
+            }
+            return iterator;
         } 
     }
 }

test/Microsoft.AspNetCore.Server.KestrelTests/MemoryPoolIteratorTests.cs

@@ -30,80 +30,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             _pool.Dispose();
         }
 
-        [Fact]
-        public void TestFindFirstEqualByte()
-        {
-            var bytes = Enumerable.Repeat<byte>(0xff, Vector<byte>.Count).ToArray();
-            for (int i = 0; i < Vector<byte>.Count; i++)
-            {
-                Vector<byte> vector = new Vector<byte>(bytes);
-                Assert.Equal(i, MemoryPoolIterator.LocateFirstFoundByte(vector));
-                bytes[i] = 0;
-            }
-
-            for (int i = 0; i < Vector<byte>.Count; i++)
-            {
-                bytes[i] = 1;
-                Vector<byte> vector = new Vector<byte>(bytes);
-                Assert.Equal(i, MemoryPoolIterator.LocateFirstFoundByte(vector));
-                bytes[i] = 0;
-            }
-        }
-
-        [Theory]
-        [InlineData("a", "a", 'a', 0)]
-        [InlineData("ab", "a", 'a', 0)]
-        [InlineData("aab", "a", 'a', 0)]
-        [InlineData("acab", "a", 'a', 0)]
-        [InlineData("acab", "c", 'c', 1)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "lo", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "ol", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "ll", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "lmr", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "rml", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyz", "mlr", 'l', 11)]
-        [InlineData("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz", "lmr", 'l', 11)]
-        [InlineData("aaaaaaaaaaalmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz", "lmr", 'l', 11)]
-        [InlineData("aaaaaaaaaaacmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz", "lmr", 'm', 12)]
-        [InlineData("aaaaaaaaaaarmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz", "lmr", 'r', 11)]
-        [InlineData("/localhost:5000/PATH/%2FPATH2/ HTTP/1.1", " %?", '%', 21)]
-        [InlineData("/localhost:5000/PATH/%2FPATH2/?key=value HTTP/1.1", " %?", '%', 21)]
-        [InlineData("/localhost:5000/PATH/PATH2/?key=value HTTP/1.1", " %?", '?', 27)]
-        [InlineData("/localhost:5000/PATH/PATH2/ HTTP/1.1", " %?", ' ', 27)]
-        public void MemorySeek(string raw, string search, char expectResult, int expectIndex)
-        {
-            var block = _pool.Lease();
-            var chars = raw.ToCharArray().Select(c => (byte)c).ToArray();
-            Buffer.BlockCopy(chars, 0, block.Array, block.Start, chars.Length);
-            block.End += chars.Length;
-
-            var begin = block.GetIterator();
-            var searchFor = search.ToCharArray();
-
-            int found = -1;
-            if (searchFor.Length == 1)
-            {
-                found = begin.Seek((byte)searchFor[0]);
-            }
-            else if (searchFor.Length == 2)
-            {
-                found = begin.Seek((byte)searchFor[0], (byte)searchFor[1]);
-            }
-            else if (searchFor.Length == 3)
-            {
-                found = begin.Seek((byte)searchFor[0], (byte)searchFor[1], (byte)searchFor[2]);
-            }
-            else
-            {
-                Assert.False(true, "Invalid test sample.");
-            }
-
-            Assert.Equal(expectResult, found);
-            Assert.Equal(expectIndex, begin.Index - block.Start);
-
-            _pool.Return(block);
-        }
-
         [Fact]
         public void Put()
         {
@@ -241,728 +167,20 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
 
         }
 
-        [Fact]
-        public void PeekLong()
-        {
-            // Arrange
-            var block = _pool.Lease();
-            var bytes = BitConverter.GetBytes(0x0102030405060708UL);
-            Buffer.BlockCopy(bytes, 0, block.Array, block.Start, bytes.Length);
-            block.End += bytes.Length;
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Assert
-            ulong result;
-            Assert.True(scan.TryPeekLong(out result));
-            Assert.Equal(0x0102030405060708UL, result);
-            Assert.Equal(originalIndex, scan.Index);
-
-            _pool.Return(block);
-        }
-
-        [Theory]
-        [InlineData(0)]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        public void PeekLongNotEnoughBytes(int totalBytes)
-        {
-            // Arrange
-            var block = _pool.Lease();
-            var bytes = BitConverter.GetBytes(0x0102030405060708UL);
-            var bytesLength = totalBytes;
-            Buffer.BlockCopy(bytes, 0, block.Array, block.Start, bytesLength);
-            block.End += bytesLength;
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Assert
-            ulong result;
-            Assert.False(scan.TryPeekLong(out result));
-            Assert.Equal(originalIndex, scan.Index);
-            _pool.Return(block);
-        }
-
-        [Theory]
-        [InlineData(0)]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        public void PeekLongNotEnoughBytesAtBlockBoundary(int firstBlockBytes)
-        {
-            // Arrange
-            var expectedResult = 0x0102030405060708UL;
-            var nextBlockBytes = 7 - firstBlockBytes;
-
-            var block = _pool.Lease();
-            block.End += firstBlockBytes;
-
-            var nextBlock = _pool.Lease();
-            nextBlock.End += nextBlockBytes;
-
-            block.Next = nextBlock;
-
-            var bytes = BitConverter.GetBytes(expectedResult);
-            Buffer.BlockCopy(bytes, 0, block.Array, block.Start, firstBlockBytes);
-            Buffer.BlockCopy(bytes, firstBlockBytes, nextBlock.Array, nextBlock.Start, nextBlockBytes);
-
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Assert
-            ulong result;
-            Assert.False(scan.TryPeekLong(out result));
-            Assert.Equal(originalIndex, scan.Index);
-
-            _pool.Return(block);
-            _pool.Return(nextBlock);
-        }
-
-        [Theory]
-        [InlineData(0)]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        [InlineData(8)]
-        public void PeekLongAtBlockBoundary(int firstBlockBytes)
-        {
-            // Arrange
-            var expectedResult = 0x0102030405060708UL;
-            var nonZeroData = 0xFF00FFFF0000FFFFUL;
-            var nextBlockBytes = 8 - firstBlockBytes;
-
-            var block = _pool.Lease();
-            block.Start += 8;
-            block.End = block.Start + firstBlockBytes;
-
-            var nextBlock = _pool.Lease();
-            nextBlock.Start += 8;
-            nextBlock.End = nextBlock.Start + nextBlockBytes;
-
-            block.Next = nextBlock;
-
-            var bytes = BitConverter.GetBytes(expectedResult);
-            Buffer.BlockCopy(bytes, 0, block.Array, block.Start, firstBlockBytes);
-            Buffer.BlockCopy(bytes, firstBlockBytes, nextBlock.Array, nextBlock.Start, nextBlockBytes);
-
-            // Fill in surrounding bytes with non-zero data
-            var nonZeroBytes = BitConverter.GetBytes(nonZeroData);
-            Buffer.BlockCopy(nonZeroBytes, 0, block.Array, block.Start - 8, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, block.Array, block.End, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, nextBlock.Array, nextBlock.Start - 8, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, nextBlock.Array, nextBlock.End, 8);
-
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Assert
-            ulong result;
-            Assert.True(scan.TryPeekLong(out result));
-            Assert.Equal(expectedResult, result);
-            Assert.Equal(originalIndex, scan.Index);
-
-            _pool.Return(block);
-            _pool.Return(nextBlock);
-        }
-
-        [Theory]
-        [InlineData(0)]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        [InlineData(8)]
-        public void PeekLongAtBlockBoundarayWithMostSignificatBitsSet(int firstBlockBytes)
-        {
-            // Arrange
-            var expectedResult = 0xFF02030405060708UL;
-            var nonZeroData = 0xFF00FFFF0000FFFFUL;
-            var nextBlockBytes = 8 - firstBlockBytes;
-
-            var block = _pool.Lease();
-            block.Start += 8;
-            block.End = block.Start + firstBlockBytes;
-
-            var nextBlock = _pool.Lease();
-            nextBlock.Start += 8;
-            nextBlock.End = nextBlock.Start + nextBlockBytes;
-
-            block.Next = nextBlock;
-
-            var expectedBytes = BitConverter.GetBytes(expectedResult);
-            Buffer.BlockCopy(expectedBytes, 0, block.Array, block.Start, firstBlockBytes);
-            Buffer.BlockCopy(expectedBytes, firstBlockBytes, nextBlock.Array, nextBlock.Start, nextBlockBytes);
-
-            // Fill in surrounding bytes with non-zero data
-            var nonZeroBytes = BitConverter.GetBytes(nonZeroData);
-            Buffer.BlockCopy(nonZeroBytes, 0, block.Array, block.Start - 8, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, block.Array, block.End, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, nextBlock.Array, nextBlock.Start - 8, 8);
-            Buffer.BlockCopy(nonZeroBytes, 0, nextBlock.Array, nextBlock.End, 8);
-
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Assert
-            ulong result;
-            Assert.True(scan.TryPeekLong(out result));
-            Assert.Equal(expectedResult, result);
-            Assert.Equal(originalIndex, scan.Index);
-
-            _pool.Return(block);
-            _pool.Return(nextBlock);
-        }
-
-        [Theory]
-        [InlineData(0)]
-        [InlineData(1)]
-        [InlineData(2)]
-        [InlineData(3)]
-        [InlineData(4)]
-        [InlineData(5)]
-        [InlineData(6)]
-        [InlineData(7)]
-        [InlineData(8)]
-        [InlineData(9)]
-        public void SkipAtBlockBoundary(int blockBytes)
-        {
-            // Arrange
-            var nextBlockBytes = 10 - blockBytes;
-
-            var block = _pool.Lease();
-            block.End += blockBytes;
-
-            var nextBlock = _pool.Lease();
-            nextBlock.End += nextBlockBytes;
-
-            block.Next = nextBlock;
-
-            var bytes = new byte[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
-            Buffer.BlockCopy(bytes, 0, block.Array, block.Start, blockBytes);
-            Buffer.BlockCopy(bytes, blockBytes, nextBlock.Array, nextBlock.Start, nextBlockBytes);
-
-            var scan = block.GetIterator();
-            var originalIndex = scan.Index;
-
-            // Act
-            scan.Skip(8);
-            var result = scan.Take();
-
-            // Assert
-            Assert.Equal(0x08, result);
-            Assert.NotEqual(originalIndex, scan.Index);
-
-            _pool.Return(block);
-            _pool.Return(nextBlock);
-        }
-
-        [Fact]
-        public void SkipThrowsWhenSkippingMoreBytesThanAvailableInSingleBlock()
-        {
-            // Arrange
-            var block = _pool.Lease();
-            block.End += 5;
-
-            var scan = block.GetIterator();
-
-            // Act/Assert
-            Assert.ThrowsAny<InvalidOperationException>(() => scan.Skip(8));
-
-            _pool.Return(block);
-        }
-
-        [Fact]
-        public void SkipThrowsWhenSkippingMoreBytesThanAvailableInMultipleBlocks()
-        {
-            // Arrange
-            var firstBlock = _pool.Lease();
-            firstBlock.End += 3;
-
-            var middleBlock = _pool.Lease();
-            middleBlock.End += 1;
-            firstBlock.Next = middleBlock;
-
-            var finalBlock = _pool.Lease();
-            finalBlock.End += 2;
-            middleBlock.Next = finalBlock;
-
-            var scan = firstBlock.GetIterator();
-
-            // Act/Assert
-            Assert.ThrowsAny<InvalidOperationException>(() => scan.Skip(8));
-
-            _pool.Return(firstBlock);
-            _pool.Return(middleBlock);
-            _pool.Return(finalBlock);
-        }
-
-
-        [Theory]
-        [MemberData(nameof(SeekByteLimitData))]
-        public void TestSeekByteLimitWithinSameBlock(string input, char seek, int limit, int expectedBytesScanned, int expectedReturnValue)
-        {
-            MemoryPoolBlock block = null;
-
-            try
-            {
-                // Arrange
-
-                block = _pool.Lease();
-                var chars = input.ToString().ToCharArray().Select(c => (byte) c).ToArray();
-                Buffer.BlockCopy(chars, 0, block.Array, block.Start, chars.Length);
-                block.End += chars.Length;
-                var scan = block.GetIterator();
-
-                // Act
-                int bytesScanned;
-                var returnValue = scan.Seek((byte)seek, out bytesScanned, limit);
-
-                // Assert
-                Assert.Equal(expectedBytesScanned, bytesScanned);
-                Assert.Equal(expectedReturnValue, returnValue);
-
-                Assert.Same(block, scan.Block);
-                var expectedEndIndex = expectedReturnValue != -1 ?
-                    block.Start + input.IndexOf(seek) :
-                    block.Start + expectedBytesScanned;
-                Assert.Equal(expectedEndIndex, scan.Index);
-            }
-            finally
-            {
-                // Cleanup
-                if (block != null) _pool.Return(block);
-            }
-        }
-
-        [Theory]
-        [MemberData(nameof(SeekByteLimitData))]
-        public void TestSeekByteLimitAcrossBlocks(string input, char seek, int limit, int expectedBytesScanned, int expectedReturnValue)
-        {
-            MemoryPoolBlock block1 = null;
-            MemoryPoolBlock block2 = null;
-            MemoryPoolBlock emptyBlock = null;
-
-            try
-            {
-                // Arrange
-                var input1 = input.Substring(0, input.Length / 2);
-                block1 = _pool.Lease();
-                var chars1 = input1.ToCharArray().Select(c => (byte)c).ToArray();
-                Buffer.BlockCopy(chars1, 0, block1.Array, block1.Start, chars1.Length);
-                block1.End += chars1.Length;
-
-                emptyBlock = _pool.Lease();
-                block1.Next = emptyBlock;
-
-                var input2 = input.Substring(input.Length / 2);
-                block2 = _pool.Lease();
-                var chars2 = input2.ToCharArray().Select(c => (byte)c).ToArray();
-                Buffer.BlockCopy(chars2, 0, block2.Array, block2.Start, chars2.Length);
-                block2.End += chars2.Length;
-                emptyBlock.Next = block2;
-
-                var scan = block1.GetIterator();
-
-                // Act
-                int bytesScanned;
-                var returnValue = scan.Seek((byte)seek, out bytesScanned, limit);
-
-                // Assert
-                Assert.Equal(expectedBytesScanned, bytesScanned);
-                Assert.Equal(expectedReturnValue, returnValue);
-
-                var seekCharIndex = input.IndexOf(seek);
-                var expectedEndBlock = limit <= input.Length / 2 ?
-                    block1 :
-                    (seekCharIndex != -1 && seekCharIndex < input.Length / 2 ? block1 : block2);
-                Assert.Same(expectedEndBlock, scan.Block);
-                var expectedEndIndex = expectedReturnValue != -1 ?
-                    expectedEndBlock.Start + (expectedEndBlock == block1 ? input1.IndexOf(seek) : input2.IndexOf(seek)) :
-                    expectedEndBlock.Start + (expectedEndBlock == block1 ? expectedBytesScanned : expectedBytesScanned - (input.Length / 2));
-                Assert.Equal(expectedEndIndex, scan.Index);
-            }
-            finally
-            {
-                // Cleanup
-                if (block1 != null) _pool.Return(block1);
-                if (emptyBlock != null) _pool.Return(emptyBlock);
-                if (block2 != null) _pool.Return(block2);
-            }
-        }
-
-        [Theory]
-        [MemberData(nameof(SeekIteratorLimitData))]
-        public void TestSeekIteratorLimitWithinSameBlock(string input, char seek, char limitAt, int expectedReturnValue)
-        {
-            MemoryPoolBlock block = null;
-
-            try
-            {
-                // Arrange
-                var afterSeek = (byte)'B';
-
-                block = _pool.Lease();
-                var chars = input.ToCharArray().Select(c => (byte)c).ToArray();
-                Buffer.BlockCopy(chars, 0, block.Array, block.Start, chars.Length);
-                block.End += chars.Length;
-                var scan1 = block.GetIterator();
-                var scan2_1 = scan1;
-                var scan2_2 = scan1;
-                var scan3_1 = scan1;
-                var scan3_2 = scan1;
-                var scan3_3 = scan1;
-                var end = scan1;
-
-                // Act
-                var endReturnValue = end.Seek((byte)limitAt);
-                var returnValue1 = scan1.Seek((byte)seek, ref end);
-                var returnValue2_1 = scan2_1.Seek((byte)seek, afterSeek, ref end);
-                var returnValue2_2 = scan2_2.Seek(afterSeek, (byte)seek, ref end);
-                var returnValue3_1 = scan3_1.Seek((byte)seek, afterSeek, afterSeek, ref end);
-                var returnValue3_2 = scan3_2.Seek(afterSeek, (byte)seek, afterSeek, ref end);
-                var returnValue3_3 = scan3_3.Seek(afterSeek, afterSeek, (byte)seek, ref end);
-
-                // Assert
-                Assert.Equal(input.Contains(limitAt) ? limitAt : -1, endReturnValue);
-                Assert.Equal(expectedReturnValue, returnValue1);
-                Assert.Equal(expectedReturnValue, returnValue2_1);
-                Assert.Equal(expectedReturnValue, returnValue2_2);
-                Assert.Equal(expectedReturnValue, returnValue3_1);
-                Assert.Equal(expectedReturnValue, returnValue3_2);
-                Assert.Equal(expectedReturnValue, returnValue3_3);
-
-                Assert.Same(block, scan1.Block);
-                Assert.Same(block, scan2_1.Block);
-                Assert.Same(block, scan2_2.Block);
-                Assert.Same(block, scan3_1.Block);
-                Assert.Same(block, scan3_2.Block);
-                Assert.Same(block, scan3_3.Block);
-
-                var expectedEndIndex = expectedReturnValue != -1 ? block.Start + input.IndexOf(seek) : end.Index;
-                Assert.Equal(expectedEndIndex, scan1.Index);
-                Assert.Equal(expectedEndIndex, scan2_1.Index);
-                Assert.Equal(expectedEndIndex, scan2_2.Index);
-                Assert.Equal(expectedEndIndex, scan3_1.Index);
-                Assert.Equal(expectedEndIndex, scan3_2.Index);
-                Assert.Equal(expectedEndIndex, scan3_3.Index);
-            }
-            finally
-            {
-                // Cleanup
-                if (block != null) _pool.Return(block);
-            }
-        }
-
-        [Theory]
-        [MemberData(nameof(SeekIteratorLimitData))]
-        public void TestSeekIteratorLimitAcrossBlocks(string input, char seek, char limitAt, int expectedReturnValue)
-        {
-            MemoryPoolBlock block1 = null;
-            MemoryPoolBlock block2 = null;
-            MemoryPoolBlock emptyBlock = null;
-
-            try
-            {
-                // Arrange
-                var afterSeek = (byte)'B';
-
-                var input1 = input.Substring(0, input.Length / 2);
-                block1 = _pool.Lease();
-                var chars1 = input1.ToCharArray().Select(c => (byte)c).ToArray();
-                Buffer.BlockCopy(chars1, 0, block1.Array, block1.Start, chars1.Length);
-                block1.End += chars1.Length;
-
-                emptyBlock = _pool.Lease();
-                block1.Next = emptyBlock;
-
-                var input2 = input.Substring(input.Length / 2);
-                block2 = _pool.Lease();
-                var chars2 = input2.ToCharArray().Select(c => (byte)c).ToArray();
-                Buffer.BlockCopy(chars2, 0, block2.Array, block2.Start, chars2.Length);
-                block2.End += chars2.Length;
-                emptyBlock.Next = block2;
-
-                var scan1 = block1.GetIterator();
-                var scan2_1 = scan1;
-                var scan2_2 = scan1;
-                var scan3_1 = scan1;
-                var scan3_2 = scan1;
-                var scan3_3 = scan1;
-                var end = scan1;
-
-                // Act
-                var endReturnValue = end.Seek((byte)limitAt);
-                var returnValue1 = scan1.Seek((byte)seek, ref end);
-                var returnValue2_1 = scan2_1.Seek((byte)seek, afterSeek, ref end);
-                var returnValue2_2 = scan2_2.Seek(afterSeek, (byte)seek, ref end);
-                var returnValue3_1 = scan3_1.Seek((byte)seek, afterSeek, afterSeek, ref end);
-                var returnValue3_2 = scan3_2.Seek(afterSeek, (byte)seek, afterSeek, ref end);
-                var returnValue3_3 = scan3_3.Seek(afterSeek, afterSeek, (byte)seek, ref end);
-
-                // Assert
-                Assert.Equal(input.Contains(limitAt) ? limitAt : -1, endReturnValue);
-                Assert.Equal(expectedReturnValue, returnValue1);
-                Assert.Equal(expectedReturnValue, returnValue2_1);
-                Assert.Equal(expectedReturnValue, returnValue2_2);
-                Assert.Equal(expectedReturnValue, returnValue3_1);
-                Assert.Equal(expectedReturnValue, returnValue3_2);
-                Assert.Equal(expectedReturnValue, returnValue3_3);
-
-                var seekCharIndex = input.IndexOf(seek);
-                var limitAtIndex = input.IndexOf(limitAt);
-                var expectedEndBlock = seekCharIndex != -1 && seekCharIndex < input.Length / 2 ?
-                    block1 :
-                    (limitAtIndex != -1 && limitAtIndex < input.Length / 2 ? block1 : block2);
-                Assert.Same(expectedEndBlock, scan1.Block);
-                Assert.Same(expectedEndBlock, scan2_1.Block);
-                Assert.Same(expectedEndBlock, scan2_2.Block);
-                Assert.Same(expectedEndBlock, scan3_1.Block);
-                Assert.Same(expectedEndBlock, scan3_2.Block);
-                Assert.Same(expectedEndBlock, scan3_3.Block);
-
-                var expectedEndIndex = expectedReturnValue != -1 ?
-                    expectedEndBlock.Start + (expectedEndBlock == block1 ? input1.IndexOf(seek) : input2.IndexOf(seek)) :
-                    end.Index;
-                Assert.Equal(expectedEndIndex, scan1.Index);
-                Assert.Equal(expectedEndIndex, scan2_1.Index);
-                Assert.Equal(expectedEndIndex, scan2_2.Index);
-                Assert.Equal(expectedEndIndex, scan3_1.Index);
-                Assert.Equal(expectedEndIndex, scan3_2.Index);
-                Assert.Equal(expectedEndIndex, scan3_3.Index);
-            }
-            finally
-            {
-                // Cleanup
-                if (block1 != null) _pool.Return(block1);
-                if (emptyBlock != null) _pool.Return(emptyBlock);
-                if (block2 != null) _pool.Return(block2);
-            }
-        }
 
         [Fact]
         public void EmptyIteratorBehaviourIsValid()
         {
             const byte byteCr = (byte)'\n';
-            ulong longValue;
             var end = default(MemoryPoolIterator);
-
+            
-            Assert.False(default(MemoryPoolIterator).TryPeekLong(out longValue));
-            Assert.Null(default(MemoryPoolIterator).GetAsciiString(ref end));
-            Assert.Null(default(MemoryPoolIterator).GetUtf8String(ref end));
-            // Assert.Equal doesn't work for default(ArraySegments)
-            Assert.True(default(MemoryPoolIterator).GetArraySegment(end).Equals(default(ArraySegment<byte>)));
             Assert.True(default(MemoryPoolIterator).IsDefault);
             Assert.True(default(MemoryPoolIterator).IsEnd);
-            Assert.Equal(default(MemoryPoolIterator).Take(), -1);
-            Assert.Equal(default(MemoryPoolIterator).Peek(), -1);
-            Assert.Equal(default(MemoryPoolIterator).Seek(byteCr), -1);
-            Assert.Equal(default(MemoryPoolIterator).Seek(byteCr, ref end), -1);
-            Assert.Equal(default(MemoryPoolIterator).Seek(byteCr, byteCr), -1);
-            Assert.Equal(default(MemoryPoolIterator).Seek(byteCr, byteCr, byteCr), -1);
 
             default(MemoryPoolIterator).CopyFrom(default(ArraySegment<byte>));
             default(MemoryPoolIterator).CopyFromAscii("");
             Assert.ThrowsAny<InvalidOperationException>(() => default(MemoryPoolIterator).Put(byteCr));
             Assert.ThrowsAny<InvalidOperationException>(() => default(MemoryPoolIterator).GetLength(end));
-            Assert.ThrowsAny<InvalidOperationException>(() => default(MemoryPoolIterator).Skip(1));
-        }
-
-        [Fact]
-        public void TestGetArraySegment()
-        {
-            MemoryPoolBlock block0 = null;
-            MemoryPoolBlock block1 = null;
-
-            var byteRange = Enumerable.Range(1, 127).Select(x => (byte)x).ToArray();
-            try
-            {
-                // Arrange
-                block0 = _pool.Lease();
-                block1 = _pool.Lease();
-
-                block0.GetIterator().CopyFrom(byteRange);
-                block1.GetIterator().CopyFrom(byteRange);
-
-                block0.Next = block1;
-
-                var begin = block0.GetIterator();
-                var end0 = begin;
-                var end1 = begin;
-
-                end0.Skip(byteRange.Length);
-                end1.Skip(byteRange.Length * 2);
-
-                // Act
-                var as0 = begin.GetArraySegment(end0);
-                var as1 = begin.GetArraySegment(end1);
-
-                // Assert
-                Assert.Equal(as0.Count, byteRange.Length);
-                Assert.Equal(as1.Count, byteRange.Length * 2);
-
-                for (var i = 1; i < byteRange.Length; i++)
-                {
-                    var asb0 = as0.Array[i + as0.Offset];
-                    var asb1 = as1.Array[i + as1.Offset];
-                    var b = byteRange[i];
-
-                    Assert.Equal(asb0, b);
-                    Assert.Equal(asb1, b);
-                }
-
-                for (var i = 1 + byteRange.Length; i < byteRange.Length * 2; i++)
-                {
-                    var asb1 = as1.Array[i + as1.Offset];
-                    var b = byteRange[i - byteRange.Length];
-
-                    Assert.Equal(asb1, b);
-                }
-
-            }
-            finally
-            {
-                if (block0 != null) _pool.Return(block0);
-                if (block1 != null) _pool.Return(block1);
-            }
-        }
-
-        [Fact]
-        public void TestTake()
-        {
-            MemoryPoolBlock block0 = null;
-            MemoryPoolBlock block1 = null;
-            MemoryPoolBlock block2 = null;
-            MemoryPoolBlock emptyBlock0 = null;
-            MemoryPoolBlock emptyBlock1 = null;
-
-            var byteRange = Enumerable.Range(1, 127).Select(x => (byte)x).ToArray();
-            try
-            {
-                // Arrange
-                block0 = _pool.Lease();
-                block1 = _pool.Lease();
-                block2 = _pool.Lease();
-                emptyBlock0 = _pool.Lease();
-                emptyBlock1 = _pool.Lease();
-
-                block0.GetIterator().CopyFrom(byteRange);
-                block1.GetIterator().CopyFrom(byteRange);
-                block2.GetIterator().CopyFrom(byteRange);
-
-                var begin = block0.GetIterator();
-
-                // Single block
-                for (var i = 0; i < byteRange.Length; i++)
-                {
-                    var t = begin.Take();
-                    var b = byteRange[i];
-
-                    Assert.Equal(t, b);
-                }
-
-                Assert.Equal(begin.Take(), -1);
-
-                // Dual block
-                block0.Next = block1;
-                begin = block0.GetIterator();
-
-                for (var block = 0; block < 2; block++)
-                {
-                    for (var i = 0; i < byteRange.Length; i++)
-                    {
-                        var t = begin.Take();
-                        var b = byteRange[i];
-
-                        Assert.Equal(t, b);
-                    }
-                }
-
-                Assert.Equal(begin.Take(), -1);
-
-                // Multi block
-                block1.Next = emptyBlock0;
-                emptyBlock0.Next = emptyBlock1;
-                emptyBlock1.Next = block2;
-                begin = block0.GetIterator();
-
-                for (var block = 0; block < 3; block++)
-                {
-                    for (var i = 0; i < byteRange.Length; i++)
-                    {
-                        var t = begin.Take();
-                        var b = byteRange[i];
-
-                        Assert.Equal(t, b);
-                    }
-                }
-
-                Assert.Equal(begin.Take(), -1);
-            }
-            finally
-            {
-                if (block0 != null) _pool.Return(block0);
-                if (block1 != null) _pool.Return(block1);
-                if (block2 != null) _pool.Return(block2);
-                if (emptyBlock0 != null) _pool.Return(emptyBlock0);
-                if (emptyBlock1 != null) _pool.Return(emptyBlock1);
-            }
-        }
-
-        [Fact]
-        public void TestTakeEmptyBlocks()
-        {
-            MemoryPoolBlock emptyBlock0 = null;
-            MemoryPoolBlock emptyBlock1 = null;
-            MemoryPoolBlock emptyBlock2 = null;
-            try
-            {
-                // Arrange
-                emptyBlock0 = _pool.Lease();
-                emptyBlock1 = _pool.Lease();
-                emptyBlock2 = _pool.Lease();
-
-                var beginEmpty = emptyBlock0.GetIterator();
-
-                // Assert
-
-                // No blocks
-                Assert.Equal(default(MemoryPoolIterator).Take(), -1);
-
-                // Single empty block
-                Assert.Equal(beginEmpty.Take(), -1);
-
-                // Dual empty block
-                emptyBlock0.Next = emptyBlock1;
-                beginEmpty = emptyBlock0.GetIterator();
-                Assert.Equal(beginEmpty.Take(), -1);
-
-                // Multi empty block
-                emptyBlock1.Next = emptyBlock2;
-                beginEmpty = emptyBlock0.GetIterator();
-                Assert.Equal(beginEmpty.Take(), -1);
-            }
-            finally
-            {
-                if (emptyBlock0 != null) _pool.Return(emptyBlock0);
-                if (emptyBlock1 != null) _pool.Return(emptyBlock1);
-                if (emptyBlock2 != null) _pool.Return(emptyBlock2);
-            }
         }
 
         [Theory]
@@ -973,23 +191,14 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         [InlineData("abcde", "abcde", 6)]
         public void TestGetAsciiStringEscaped(string input, string expected, int maxChars)
         {
-            MemoryPoolBlock block = null;
-
-            try
-            {
                 // Arrange
-                var buffer = new Span<byte>(Encoding.ASCII.GetBytes(input));
+            var buffer = new Span<byte>(Encoding.ASCII.GetBytes(input));
 
-                // Act
+            // Act
-                var result = buffer.GetAsciiStringEscaped(maxChars);
+            var result = buffer.GetAsciiStringEscaped(maxChars);
 
-                // Assert
+            // Assert
-                Assert.Equal(expected, result);
+            Assert.Equal(expected, result);
-            }
-            finally
-            {
-                if (block != null) _pool.Return(block);
-            }
         }
 
         [Fact]

test/Microsoft.AspNetCore.Server.KestrelTests/UrlPathDecoder.cs

@@ -1,226 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Linq;
-using Microsoft.AspNetCore.Server.Kestrel.Internal.Http;
-using Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure;
-using Xunit;
-
-namespace Microsoft.AspNetCore.Server.KestrelTests
-{
-    public class UrlPathDecoderTests
-    {
-        [Fact]
-        public void Empty()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, string.Empty, string.Empty);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Fact]
-        public void WhiteSpace()
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, "    ", "    ");
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        [InlineData("/foo/bar", "/foo/bar")]
-        [InlineData("/foo/BAR", "/foo/BAR")]
-        [InlineData("/foo/", "/foo/")]
-        [InlineData("/", "/")]
-        public void NormalCases(string raw, string expect)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, raw, expect);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        [InlineData("%2F", "%2F")]
-        [InlineData("/foo%2Fbar", "/foo%2Fbar")]
-        [InlineData("/foo%2F%20bar", "/foo%2F bar")]
-        public void SkipForwardSlash(string raw, string expect)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, raw, expect);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        [InlineData("%D0%A4", "Ф")]
-        [InlineData("%d0%a4", "Ф")]
-        [InlineData("%E0%A4%AD", "भ")]
-        [InlineData("%e0%A4%Ad", "भ")]
-        [InlineData("%F0%A4%AD%A2", "𤭢")]
-        [InlineData("%F0%a4%Ad%a2", "𤭢")]
-        [InlineData("%48%65%6C%6C%6F%20%57%6F%72%6C%64", "Hello World")]
-        [InlineData("%48%65%6C%6C%6F%2D%C2%B5%40%C3%9F%C3%B6%C3%A4%C3%BC%C3%A0%C3%A1", "Hello-µ@ßöäüàá")]
-        // Test the borderline cases of overlong UTF8.
-        [InlineData("%C2%80", "\u0080")]
-        [InlineData("%E0%A0%80", "\u0800")]
-        [InlineData("%F0%90%80%80", "\U00010000")]
-        [InlineData("%63", "c")]
-        [InlineData("%32", "2")]
-        [InlineData("%20", " ")]
-        public void ValidUTF8(string raw, string expect)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, raw, expect);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        [InlineData("%C3%84ra%20Benetton", "Ära Benetton")]
-        [InlineData("%E6%88%91%E8%87%AA%E6%A8%AA%E5%88%80%E5%90%91%E5%A4%A9%E7%AC%91%E5%8E%BB%E7%95%99%E8%82%9D%E8%83%86%E4%B8%A4%E6%98%86%E4%BB%91", "我自横刀向天笑去留肝胆两昆仑")]
-        public void Internationalized(string raw, string expect)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, raw, expect);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        // Overlong ASCII
-        [InlineData("%C0%A4", "%C0%A4")]
-        [InlineData("%C1%BF", "%C1%BF")]
-        [InlineData("%E0%80%AF", "%E0%80%AF")]
-        [InlineData("%E0%9F%BF", "%E0%9F%BF")]
-        [InlineData("%F0%80%80%AF", "%F0%80%80%AF")]
-        [InlineData("%F0%8F%8F%BF", "%F0%8F%8F%BF")]
-        // Incomplete
-        [InlineData("%", "%")]
-        [InlineData("%%", "%%")]
-        [InlineData("%A", "%A")]
-        [InlineData("%Y", "%Y")]
-        // Mixed
-        [InlineData("%%32", "%2")]
-        [InlineData("%%20", "% ")]
-        [InlineData("%C0%A4%32", "%C0%A42")]
-        [InlineData("%32%C0%A4%32", "2%C0%A42")]
-        [InlineData("%C0%32%A4", "%C02%A4")]
-        public void InvalidUTF8(string raw, string expect)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                PositiveAssert(mem, raw, expect);
-
-                pool.Return(mem);
-            }
-        }
-
-        [Theory]
-        [InlineData("/foo%2Fbar", 10, "/foo%2Fbar", 10)]
-        [InlineData("/foo%2Fbar", 9, "/foo%2Fba", 9)]
-        [InlineData("/foo%2Fbar", 8, "/foo%2Fb", 8)]
-        [InlineData("%D0%A4", 6, "Ф", 1)]
-        [InlineData("%D0%A4", 5, "%D0%A", 5)]
-        [InlineData("%D0%A4", 4, "%D0%", 4)]
-        [InlineData("%D0%A4", 3, "%D0", 3)]
-        [InlineData("%D0%A4", 2, "%D", 2)]
-        [InlineData("%D0%A4", 1, "%", 1)]
-        [InlineData("%D0%A4", 0, "", 0)]
-        [InlineData("%C2%B5%40%C3%9F%C3%B6%C3%A4%C3%BC%C3%A0%C3%A1", 45, "µ@ßöäüàá", 8)]
-        [InlineData("%C2%B5%40%C3%9F%C3%B6%C3%A4%C3%BC%C3%A0%C3%A1", 44, "µ@ßöäüà%C3%A", 12)]
-        public void DecodeWithBoundary(string raw, int rawLength, string expect, int expectLength)
-        {
-            using (var pool = new MemoryPool())
-            {
-                var mem = pool.Lease();
-
-                var begin = BuildSample(mem, raw);
-                var end = GetIterator(begin, rawLength);
-
-                var end2 = UrlPathDecoder.Unescape(begin, end);
-                var result = begin.GetUtf8String(ref end2);
-
-                Assert.Equal(expectLength, result.Length);
-                Assert.Equal(expect, result);
-
-                pool.Return(mem);
-            }
-        }
-
-        private MemoryPoolIterator BuildSample(MemoryPoolBlock mem, string data)
-        {
-            var store = data.Select(c => (byte)c).ToArray();
-            mem.GetIterator().CopyFrom(new ArraySegment<byte>(store));
-
-            return mem.GetIterator();
-        }
-
-        private MemoryPoolIterator GetIterator(MemoryPoolIterator begin, int displacement)
-        {
-            var result = begin;
-            for (int i = 0; i < displacement; ++i)
-            {
-                result.Take();
-            }
-
-            return result;
-        }
-
-        private void PositiveAssert(MemoryPoolBlock mem, string raw, string expect)
-        {
-            var begin = BuildSample(mem, raw);
-            var end = GetIterator(begin, raw.Length);
-
-            var result = UrlPathDecoder.Unescape(begin, end);
-            Assert.Equal(expect, begin.GetUtf8String(ref result));
-        }
-
-        private void PositiveAssert(MemoryPoolBlock mem, string raw)
-        {
-            var begin = BuildSample(mem, raw);
-            var end = GetIterator(begin, raw.Length);
-
-            var result = UrlPathDecoder.Unescape(begin, end);
-            Assert.NotEqual(raw.Length, begin.GetUtf8String(ref result).Length);
-        }
-
-        private void NegativeAssert(MemoryPoolBlock mem, string raw)
-        {
-            var begin = BuildSample(mem, raw);
-            var end = GetIterator(begin, raw.Length);
-
-            var resultEnd = UrlPathDecoder.Unescape(begin, end);
-            var result = begin.GetUtf8String(ref resultEnd);
-            Assert.Equal(raw, result);
-        }
-    }
-}

test/shared/HttpParsingData.cs

@@ -4,14 +4,13 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using Microsoft.AspNetCore.Server.Kestrel;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Testing
 {
     public class HttpParsingData
     {
-        public static IEnumerable<string[]> ValidRequestLineData
+        public static IEnumerable<string[]> RequestLineValidData
         {
             get
             {
@@ -20,7 +19,7 @@ namespace Microsoft.AspNetCore.Testing
                     "GET",
                     "CUSTOM",
                 };
-                var targets = new[]
+                var paths = new[]
                 {
                     Tuple.Create("/", "/"),
                     Tuple.Create("/abc", "/abc"),
@@ -57,166 +56,154 @@ namespace Microsoft.AspNetCore.Testing
                 };
 
                 return from method in methods
-                       from target in targets
+                       from path in paths
                        from queryString in queryStrings
                        from httpVersion in httpVersions
                        select new[]
                        {
-                           $"{method} {target.Item1}{queryString} {httpVersion}\r\n",
+                           $"{method} {path.Item1}{queryString} {httpVersion}\r\n",
                            method,
-                           $"{target.Item2}",
+                           $"{path.Item1}{queryString}",
+                           $"{path.Item1}",
+                           $"{path.Item2}",
                            queryString,
                            httpVersion
                        };
             }
         }
 
-        // All these test cases must end in '\n', otherwise the server will spin forever
+        public static IEnumerable<string> RequestLineIncompleteData => new[]
-        public static IEnumerable<object[]> InvalidRequestLineData
         {
-            get
+            "G",
-            {
+            "GE",
-                var invalidRequestLines = new[]
+            "GET",
-                {
+            "GET ",
-                    "G\r\n",
+            "GET /",
-                    "GE\r\n",
+            "GET / ",
-                    "GET\r\n",
+            "GET / H",
-                    "GET \r\n",
+            "GET / HT",
-                    "GET /\r\n",
+            "GET / HTT",
-                    "GET / \r\n",
+            "GET / HTTP",
-                    "GET/HTTP/1.1\r\n",
+            "GET / HTTP/",
-                    "GET /HTTP/1.1\r\n",
+            "GET / HTTP/1",
-                    " \r\n",
+            "GET / HTTP/1.",
-                    "  \r\n",
+            "GET / HTTP/1.1",
-                    "/ HTTP/1.1\r\n",
+            "GET / HTTP/1.1\r",
-                    " / HTTP/1.1\r\n",
+        };
-                    "/ \r\n",
-                    "GET  \r\n",
-                    "GET  HTTP/1.0\r\n",
-                    "GET  HTTP/1.1\r\n",
-                    "GET / \n",
-                    "GET / HTTP/1.0\n",
-                    "GET / HTTP/1.1\n",
-                    "GET / HTTP/1.0\rA\n",
-                    "GET / HTTP/1.1\ra\n",
-                    "GET? / HTTP/1.1\r\n",
-                    "GET ? HTTP/1.1\r\n",
-                    "GET /a?b=cHTTP/1.1\r\n",
-                    "GET /a%20bHTTP/1.1\r\n",
-                    "GET /a%20b?c=dHTTP/1.1\r\n",
-                    "GET %2F HTTP/1.1\r\n",
-                    "GET %00 HTTP/1.1\r\n",
-                    "CUSTOM \r\n",
-                    "CUSTOM /\r\n",
-                    "CUSTOM / \r\n",
-                    "CUSTOM /HTTP/1.1\r\n",
-                    "CUSTOM  \r\n",
-                    "CUSTOM  HTTP/1.0\r\n",
-                    "CUSTOM  HTTP/1.1\r\n",
-                    "CUSTOM / \n",
-                    "CUSTOM / HTTP/1.0\n",
-                    "CUSTOM / HTTP/1.1\n",
-                    "CUSTOM / HTTP/1.0\rA\n",
-                    "CUSTOM / HTTP/1.1\ra\n",
-                    "CUSTOM ? HTTP/1.1\r\n",
-                    "CUSTOM /a?b=cHTTP/1.1\r\n",
-                    "CUSTOM /a%20bHTTP/1.1\r\n",
-                    "CUSTOM /a%20b?c=dHTTP/1.1\r\n",
-                    "CUSTOM %2F HTTP/1.1\r\n",
-                    "CUSTOM %00 HTTP/1.1\r\n",
-                    // Bad HTTP Methods (invalid according to RFC)
-                    "( / HTTP/1.0\r\n",
-                    ") / HTTP/1.0\r\n",
-                    "< / HTTP/1.0\r\n",
-                    "> / HTTP/1.0\r\n",
-                    "@ / HTTP/1.0\r\n",
-                    ", / HTTP/1.0\r\n",
-                    "; / HTTP/1.0\r\n",
-                    ": / HTTP/1.0\r\n",
-                    "\\ / HTTP/1.0\r\n",
-                    "\" / HTTP/1.0\r\n",
-                    "/ / HTTP/1.0\r\n",
-                    "[ / HTTP/1.0\r\n",
-                    "] / HTTP/1.0\r\n",
-                    "? / HTTP/1.0\r\n",
-                    "= / HTTP/1.0\r\n",
-                    "{ / HTTP/1.0\r\n",
-                    "} / HTTP/1.0\r\n",
-                    "get@ / HTTP/1.0\r\n",
-                    "post= / HTTP/1.0\r\n",
-                };
 
-                var encodedNullCharInTargetRequestLines = new[]
+        public static IEnumerable<string> RequestLineInvalidData => new[]
-                {
-                    "GET /%00 HTTP/1.1\r\n",
-                    "GET /%00%00 HTTP/1.1\r\n",
-                    "GET /%E8%00%84 HTTP/1.1\r\n",
-                    "GET /%E8%85%00 HTTP/1.1\r\n",
-                    "GET /%F3%00%82%86 HTTP/1.1\r\n",
-                    "GET /%F3%85%00%82 HTTP/1.1\r\n",
-                    "GET /%F3%85%82%00 HTTP/1.1\r\n",
-                    "GET /%E8%85%00 HTTP/1.1\r\n",
-                    "GET /%E8%01%00 HTTP/1.1\r\n",
-                };
-
-                var nullCharInTargetRequestLines = new[]
-                {
-                    "GET \0 HTTP/1.1\r\n",
-                    "GET /\0 HTTP/1.1\r\n",
-                    "GET /\0\0 HTTP/1.1\r\n",
-                    "GET /%C8\0 HTTP/1.1\r\n",
-                };
-
-                return invalidRequestLines.Select(requestLine => new object[]
-                       {
-                           requestLine,
-                           typeof(BadHttpRequestException),
-                           $"Invalid request line: {requestLine.Replace("\r", "<0x0D>").Replace("\n", "<0x0A>")}"
-                       })
-                       .Concat(encodedNullCharInTargetRequestLines.Select(requestLine => new object[]
-                        {
-                            requestLine,
-                            typeof(InvalidOperationException),
-                            $"The path contains null characters."
-                        }))
-                       .Concat(nullCharInTargetRequestLines.Select(requestLine => new object[]
-                        {
-                            requestLine,
-                            typeof(InvalidOperationException),
-                            new InvalidOperationException().Message
-                        }));
-            }
-        }
-
-        public static TheoryData<string> UnrecognizedHttpVersionData
         {
-            get
+            "G\r\n",
-            {
+            "GE\r\n",
-                return new TheoryData<string>
+            "GET\r\n",
-                {
+            "GET \r\n",
-                    "H",
+            "GET /\r\n",
-                    "HT",
+            "GET / \r\n",
-                    "HTT",
+            "GET/HTTP/1.1\r\n",
-                    "HTTP",
+            "GET /HTTP/1.1\r\n",
-                    "HTTP/",
+            " \r\n",
-                    "HTTP/1",
+            "  \r\n",
-                    "HTTP/1.",
+            "/ HTTP/1.1\r\n",
-                    "http/1.0",
+            " / HTTP/1.1\r\n",
-                    "http/1.1",
+            "/ \r\n",
-                    "HTTP/1.1 ",
+            "GET  \r\n",
-                    "HTTP/1.0a",
+            "GET  HTTP/1.0\r\n",
-                    "HTTP/1.0ab",
+            "GET  HTTP/1.1\r\n",
-                    "HTTP/1.1a",
+            "GET / \n",
-                    "HTTP/1.1ab",
+            "GET / HTTP/1.0\n",
-                    "HTTP/1.2",
+            "GET / HTTP/1.1\n",
-                    "HTTP/3.0",
+            "GET / HTTP/1.0\rA\n",
-                    "hello",
+            "GET / HTTP/1.1\ra\n",
-                    "8charact",
+            "GET? / HTTP/1.1\r\n",
-                };
+            "GET ? HTTP/1.1\r\n",
-            }
+            "GET /a?b=cHTTP/1.1\r\n",
-        }
+            "GET /a%20bHTTP/1.1\r\n",
+            "GET /a%20b?c=dHTTP/1.1\r\n",
+            "GET %2F HTTP/1.1\r\n",
+            "GET %00 HTTP/1.1\r\n",
+            "CUSTOM \r\n",
+            "CUSTOM /\r\n",
+            "CUSTOM / \r\n",
+            "CUSTOM /HTTP/1.1\r\n",
+            "CUSTOM  \r\n",
+            "CUSTOM  HTTP/1.0\r\n",
+            "CUSTOM  HTTP/1.1\r\n",
+            "CUSTOM / \n",
+            "CUSTOM / HTTP/1.0\n",
+            "CUSTOM / HTTP/1.1\n",
+            "CUSTOM / HTTP/1.0\rA\n",
+            "CUSTOM / HTTP/1.1\ra\n",
+            "CUSTOM ? HTTP/1.1\r\n",
+            "CUSTOM /a?b=cHTTP/1.1\r\n",
+            "CUSTOM /a%20bHTTP/1.1\r\n",
+            "CUSTOM /a%20b?c=dHTTP/1.1\r\n",
+            "CUSTOM %2F HTTP/1.1\r\n",
+            "CUSTOM %00 HTTP/1.1\r\n",
+            // Bad HTTP Methods (invalid according to RFC)
+            "( / HTTP/1.0\r\n",
+            ") / HTTP/1.0\r\n",
+            "< / HTTP/1.0\r\n",
+            "> / HTTP/1.0\r\n",
+            "@ / HTTP/1.0\r\n",
+            ", / HTTP/1.0\r\n",
+            "; / HTTP/1.0\r\n",
+            ": / HTTP/1.0\r\n",
+            "\\ / HTTP/1.0\r\n",
+            "\" / HTTP/1.0\r\n",
+            "/ / HTTP/1.0\r\n",
+            "[ / HTTP/1.0\r\n",
+            "] / HTTP/1.0\r\n",
+            "? / HTTP/1.0\r\n",
+            "= / HTTP/1.0\r\n",
+            "{ / HTTP/1.0\r\n",
+            "} / HTTP/1.0\r\n",
+            "get@ / HTTP/1.0\r\n",
+            "post= / HTTP/1.0\r\n",
+        };
 
-        public static IEnumerable<object[]> InvalidRequestHeaderData
+        public static IEnumerable<string> RequestLineWithEncodedNullCharInTargetData => new[]
+        {
+            "GET /%00 HTTP/1.1\r\n",
+            "GET /%00%00 HTTP/1.1\r\n",
+            "GET /%E8%00%84 HTTP/1.1\r\n",
+            "GET /%E8%85%00 HTTP/1.1\r\n",
+            "GET /%F3%00%82%86 HTTP/1.1\r\n",
+            "GET /%F3%85%00%82 HTTP/1.1\r\n",
+            "GET /%F3%85%82%00 HTTP/1.1\r\n",
+            "GET /%E8%01%00 HTTP/1.1\r\n",
+        };
+
+        public static IEnumerable<string> RequestLineWithNullCharInTargetData => new[]
+        {
+            "GET \0 HTTP/1.1\r\n",
+            "GET /\0 HTTP/1.1\r\n",
+            "GET /\0\0 HTTP/1.1\r\n",
+            "GET /%C8\0 HTTP/1.1\r\n",
+        };
+
+        public static TheoryData<string> UnrecognizedHttpVersionData => new TheoryData<string>
+        {
+            "H",
+            "HT",
+            "HTT",
+            "HTTP",
+            "HTTP/",
+            "HTTP/1",
+            "HTTP/1.",
+            "http/1.0",
+            "http/1.1",
+            "HTTP/1.1 ",
+            "HTTP/1.0a",
+            "HTTP/1.0ab",
+            "HTTP/1.1a",
+            "HTTP/1.1ab",
+            "HTTP/1.2",
+            "HTTP/3.0",
+            "hello",
+            "8charact",
+        };
+
+        public static IEnumerable<object[]> RequestHeaderInvalidData
         {
             get
             {
@@ -245,6 +232,14 @@ namespace Microsoft.AspNetCore.Testing
                     "Header-1: value1\rHeader-2: value2\r\n\r\n",
                     "Header-1: value1\r\nHeader-2: value2\r\r\n",
                     "Header-1: value1\r\nHeader-2: v\ralue2\r\n",
+                    "Header-1: Value__\rVector16________Vector32\r\n",
+                    "Header-1: Value___Vector16\r________Vector32\r\n",
+                    "Header-1: Value___Vector16_______\rVector32\r\n",
+                    "Header-1: Value___Vector16________Vector32\r\r\n",
+                    "Header-1: Value___Vector16________Vector32_\r\r\n",
+                    "Header-1: Value___Vector16________Vector32Value___Vector16_______\rVector32\r\n",
+                    "Header-1: Value___Vector16________Vector32Value___Vector16________Vector32\r\r\n",
+                    "Header-1: Value___Vector16________Vector32Value___Vector16________Vector32_\r\r\n",
                 };
 
                 // Missing colon
@@ -253,6 +248,7 @@ namespace Microsoft.AspNetCore.Testing
                     "Header-1 value1\r\n\r\n",
                     "Header-1 value1\r\nHeader-2: value2\r\n\r\n",
                     "Header-1: value1\r\nHeader-2 value2\r\n\r\n",
+                    "\n"
                 };
 
                 // Starting with whitespace
@@ -269,9 +265,20 @@ namespace Microsoft.AspNetCore.Testing
                 {
                     "Header : value\r\n\r\n",
                     "Header\t: value\r\n\r\n",
+                    "Header\r: value\r\n\r\n",
+                    "Header_\rVector16: value\r\n\r\n",
+                    "Header__Vector16\r: value\r\n\r\n",
+                    "Header__Vector16_\r: value\r\n\r\n",
+                    "Header_\rVector16________Vector32: value\r\n\r\n",
+                    "Header__Vector16________Vector32\r: value\r\n\r\n",
+                    "Header__Vector16________Vector32_\r: value\r\n\r\n",
+                    "Header__Vector16________Vector32Header_\rVector16________Vector32: value\r\n\r\n",
+                    "Header__Vector16________Vector32Header__Vector16________Vector32\r: value\r\n\r\n",
+                    "Header__Vector16________Vector32Header__Vector16________Vector32_\r: value\r\n\r\n",
                     "Header 1: value1\r\nHeader-2: value2\r\n\r\n",
                     "Header 1 : value1\r\nHeader-2: value2\r\n\r\n",
                     "Header 1\t: value1\r\nHeader-2: value2\r\n\r\n",
+                    "Header 1\r: value1\r\nHeader-2: value2\r\n\r\n",
                     "Header-1: value1\r\nHeader 2: value2\r\n\r\n",
                     "Header-1: value1\r\nHeader-2 : value2\r\n\r\n",
                     "Header-1: value1\r\nHeader-2\t: value2\r\n\r\n",
@@ -287,11 +294,11 @@ namespace Microsoft.AspNetCore.Testing
 
                 return new[]
                 {
-                    Tuple.Create(headersWithLineFolding,"Header value line folding not supported."),
+                    Tuple.Create(headersWithLineFolding, "Whitespace is not allowed in header name."),
-                    Tuple.Create(headersWithCRInValue,"Header value must not contain CR characters."),
+                    Tuple.Create(headersWithCRInValue, "Header value must not contain CR characters."),
-                    Tuple.Create(headersWithMissingColon,"No ':' character found in header line."),
+                    Tuple.Create(headersWithMissingColon, "No ':' character found in header line."),
-                    Tuple.Create(headersStartingWithWhitespace, "Header line must not start with whitespace."),
+                    Tuple.Create(headersStartingWithWhitespace, "Whitespace is not allowed in header name."),
-                    Tuple.Create(headersWithWithspaceInName,"Whitespace is not allowed in header name."),
+                    Tuple.Create(headersWithWithspaceInName, "Whitespace is not allowed in header name."),
                     Tuple.Create(headersNotEndingInCrLfLine, "Headers corrupted, invalid header sequence.")
                 }
                 .SelectMany(t => t.Item1.Select(headers => new[] { headers, t.Item2 }));