aspnetcore/src/Servers/Kestrel/shared/KnownHeaders.cs

999 lines
39 KiB
C#

// 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.Diagnostics;
using System.Linq;
using System.Text;
namespace CodeGenerator
{
public class KnownHeaders
{
public readonly static KnownHeader[] RequestHeaders;
public readonly static KnownHeader[] ResponseHeaders;
public readonly static KnownHeader[] ResponseTrailers;
static KnownHeaders()
{
var requestPrimaryHeaders = new[]
{
"Accept",
"Connection",
"Host",
"User-Agent"
};
var responsePrimaryHeaders = new[]
{
"Connection",
"Date",
"Content-Type",
"Server",
"Content-Length",
};
var commonHeaders = new[]
{
"Cache-Control",
"Connection",
"Date",
"Keep-Alive",
"Pragma",
"Trailer",
"Transfer-Encoding",
"Upgrade",
"Via",
"Warning",
"Allow",
"Content-Type",
"Content-Encoding",
"Content-Language",
"Content-Location",
"Content-MD5",
"Content-Range",
"Expires",
"Last-Modified"
};
// http://www.w3.org/TR/cors/#syntax
var corsRequestHeaders = new[]
{
"Origin",
"Access-Control-Request-Method",
"Access-Control-Request-Headers",
};
var requestHeadersExistence = new[]
{
"Connection",
"Transfer-Encoding",
};
var requestHeadersCount = new[]
{
"Host"
};
RequestHeaders = commonHeaders.Concat(new[]
{
"Accept",
"Accept-Charset",
"Accept-Encoding",
"Accept-Language",
"Authorization",
"Cookie",
"Expect",
"From",
"Host",
"If-Match",
"If-Modified-Since",
"If-None-Match",
"If-Range",
"If-Unmodified-Since",
"Max-Forwards",
"Proxy-Authorization",
"Referer",
"Range",
"TE",
"Translate",
"User-Agent",
"DNT",
"Upgrade-Insecure-Requests"
})
.Concat(corsRequestHeaders)
.Select((header, index) => new KnownHeader
{
Name = header,
Index = index,
PrimaryHeader = requestPrimaryHeaders.Contains(header),
ExistenceCheck = requestHeadersExistence.Contains(header),
FastCount = requestHeadersCount.Contains(header)
})
.Concat(new[] { new KnownHeader
{
Name = "Content-Length",
Index = -1,
PrimaryHeader = requestPrimaryHeaders.Contains("Content-Length")
}})
.ToArray();
var responseHeadersExistence = new[]
{
"Connection",
"Server",
"Date",
"Transfer-Encoding"
};
var enhancedHeaders = new[]
{
"Connection",
"Server",
"Date",
"Transfer-Encoding"
};
// http://www.w3.org/TR/cors/#syntax
var corsResponseHeaders = new[]
{
"Access-Control-Allow-Credentials",
"Access-Control-Allow-Headers",
"Access-Control-Allow-Methods",
"Access-Control-Allow-Origin",
"Access-Control-Expose-Headers",
"Access-Control-Max-Age",
};
ResponseHeaders = commonHeaders.Concat(new[]
{
"Accept-Ranges",
"Age",
"ETag",
"Location",
"Proxy-Authenticate",
"Retry-After",
"Server",
"Set-Cookie",
"Vary",
"WWW-Authenticate",
})
.Concat(corsResponseHeaders)
.Select((header, index) => new KnownHeader
{
Name = header,
Index = index,
EnhancedSetter = enhancedHeaders.Contains(header),
ExistenceCheck = responseHeadersExistence.Contains(header),
PrimaryHeader = responsePrimaryHeaders.Contains(header)
})
.Concat(new[] { new KnownHeader
{
Name = "Content-Length",
Index = 63,
EnhancedSetter = enhancedHeaders.Contains("Content-Length"),
PrimaryHeader = responsePrimaryHeaders.Contains("Content-Length")
}})
.ToArray();
ResponseTrailers = new[]
{
"ETag",
}
.Select((header, index) => new KnownHeader
{
Name = header,
Index = index,
EnhancedSetter = enhancedHeaders.Contains(header),
ExistenceCheck = responseHeadersExistence.Contains(header),
PrimaryHeader = responsePrimaryHeaders.Contains(header)
})
.ToArray();
}
static string Each<T>(IEnumerable<T> values, Func<T, string> formatter)
{
return values.Any() ? values.Select(formatter).Aggregate((a, b) => a + b) : "";
}
static string Each<T>(IEnumerable<T> values, Func<T, int, string> formatter)
{
return values.Any() ? values.Select(formatter).Aggregate((a, b) => a + b) : "";
}
static string AppendSwitch(IEnumerable<IGrouping<int, KnownHeader>> values) =>
$@"switch (name.Length)
{{{Each(values, byLength => $@"
case {byLength.Key}:{AppendSwitchSection(byLength.Key, byLength.OrderBy(h => (h.PrimaryHeader ? "_" : "") + h.Name))}
break;")}
}}";
static string AppendSwitchSection(int length, IOrderedEnumerable<KnownHeader> values)
{
var useVarForFirstTerm = values.Count() > 1 && values.Select(h => h.FirstNameIgnoreCaseSegment()).Distinct().Count() == 1;
var firstTermVarExpression = values.Select(h => h.FirstNameIgnoreCaseSegment()).FirstOrDefault();
var firstTermVar = $"firstTerm{length}";
var start = "";
if (useVarForFirstTerm)
{
start = $@"
var {firstTermVar} = {firstTermVarExpression};";
}
else
{
firstTermVar = "";
}
var groups = values.GroupBy(header => header.EqualIgnoreCaseBytesFirstTerm());
return start + $@"{Each(groups, (byFirstTerm, i) => $@"{(byFirstTerm.Count() == 1 ? $@"{Each(byFirstTerm, header => $@"
{(i > 0 ? "else " : "")}if ({header.EqualIgnoreCaseBytes(firstTermVar)})
{{{(header.Identifier == "ContentLength" ? $@"
AppendContentLength(value);
return;" : $@"
flag = {header.FlagBit()};
values = ref _headers._{header.Identifier};")}
}}")}" : $@"
if ({byFirstTerm.Key.Replace(firstTermVarExpression, firstTermVar)})
{{{Each(byFirstTerm, (header, i) => $@"
{(i > 0 ? "else " : "")}if ({header.EqualIgnoreCaseBytesSecondTermOnwards()})
{{{(header.Identifier == "ContentLength" ? $@"
AppendContentLength(value);
return;" : $@"
flag = {header.FlagBit()};
values = ref _headers._{header.Identifier};")}
}}")}
}}")}")}";
}
public class KnownHeader
{
public string Name { get; set; }
public int Index { get; set; }
public string Identifier => Name.Replace("-", "");
public byte[] Bytes => Encoding.ASCII.GetBytes($"\r\n{Name}: ");
public int BytesOffset { get; set; }
public int BytesCount { get; set; }
public bool ExistenceCheck { get; set; }
public bool FastCount { get; set; }
public bool EnhancedSetter { get; set; }
public bool PrimaryHeader { get; set; }
public string FlagBit() => $"{"0x" + (1L << Index).ToString("x")}L";
public string TestBit() => $"(_bits & {"0x" + (1L << Index).ToString("x")}L) != 0";
public string TestTempBit() => $"(tempBits & {"0x" + (1L << Index).ToString("x")}L) != 0";
public string TestNotTempBit() => $"(tempBits & ~{"0x" + (1L << Index).ToString("x")}L) == 0";
public string TestNotBit() => $"(_bits & {"0x" + (1L << Index).ToString("x")}L) == 0";
public string SetBit() => $"_bits |= {"0x" + (1L << Index).ToString("x")}L";
public string ClearBit() => $"_bits &= ~{"0x" + (1L << Index).ToString("x")}L";
private void GetMaskAndComp(string name, int offset, int count, out ulong mask, out ulong comp)
{
mask = 0;
comp = 0;
for (var scan = 0; scan < count; scan++)
{
var ch = (byte)name[offset + count - scan - 1];
var isAlpha = (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
comp = (comp << 8) + (ch & (isAlpha ? 0xdfu : 0xffu));
mask = (mask << 8) + (isAlpha ? 0xdfu : 0xffu);
}
}
private string NameTerm(string name, int offset, int count, string type, string suffix)
{
GetMaskAndComp(name, offset, count, out var mask, out var comp);
if (offset == 0)
{
if (type == "byte")
{
return $"(nameStart & 0x{mask:x}{suffix})";
}
else
{
return $"(Unsafe.ReadUnaligned<{type}>(ref nameStart) & 0x{mask:x}{suffix})";
}
}
else
{
if (type == "byte")
{
return $"(Unsafe.AddByteOffset(ref nameStart, (IntPtr){offset / count}) & 0x{mask:x}{suffix})";
}
else if ((offset / count) == 1)
{
return $"(Unsafe.ReadUnaligned<{type}>(ref Unsafe.AddByteOffset(ref nameStart, (IntPtr)sizeof({type}))) & 0x{mask:x}{suffix})";
}
else
{
return $"(Unsafe.ReadUnaligned<{type}>(ref Unsafe.AddByteOffset(ref nameStart, (IntPtr)({offset / count} * sizeof({type})))) & 0x{mask:x}{suffix})";
}
}
}
private string EqualityTerm(string name, int offset, int count, string type, string suffix)
{
GetMaskAndComp(name, offset, count, out var mask, out var comp);
return $"0x{comp:x}{suffix}";
}
private string Term(string name, int offset, int count, string type, string suffix)
{
GetMaskAndComp(name, offset, count, out var mask, out var comp);
return $"({NameTerm(name, offset, count, type, suffix)} == {EqualityTerm(name, offset, count, type, suffix)})";
}
public string FirstNameIgnoreCaseSegment()
{
var result = "";
if (Name.Length >= 8)
{
result = NameTerm(Name, 0, 8, "ulong", "uL");
}
else if (Name.Length >= 4)
{
result = NameTerm(Name, 0, 4, "uint", "u");
}
else if (Name.Length >= 2)
{
result = NameTerm(Name, 0, 2, "ushort", "u");
}
else
{
result = NameTerm(Name, 0, 1, "byte", "u");
}
return result;
}
public string EqualIgnoreCaseBytes(string firstTermVar = "")
{
if (!string.IsNullOrEmpty(firstTermVar))
{
return EqualIgnoreCaseBytesWithVar(firstTermVar);
}
var result = "";
var delim = "";
var index = 0;
while (index != Name.Length)
{
if (Name.Length - index >= 8)
{
result += delim + Term(Name, index, 8, "ulong", "uL");
index += 8;
}
else if (Name.Length - index >= 4)
{
result += delim + Term(Name, index, 4, "uint", "u");
index += 4;
}
else if (Name.Length - index >= 2)
{
result += delim + Term(Name, index, 2, "ushort", "u");
index += 2;
}
else
{
result += delim + Term(Name, index, 1, "byte", "u");
index += 1;
}
delim = " && ";
}
return result;
string EqualIgnoreCaseBytesWithVar(string firstTermVar)
{
var result = "";
var delim = " && ";
var index = 0;
var isFirst = true;
while (index != Name.Length)
{
if (Name.Length - index >= 8)
{
if (isFirst)
{
result = $"({firstTermVar} == {EqualityTerm(Name, index, 8, "ulong", "uL")})";
}
else
{
result += delim + Term(Name, index, 8, "ulong", "uL");
}
index += 8;
}
else if (Name.Length - index >= 4)
{
if (isFirst)
{
result = $"({firstTermVar} == {EqualityTerm(Name, index, 4, "uint", "u")})";
}
else
{
result += delim + Term(Name, index, 4, "uint", "u");
}
index += 4;
}
else if (Name.Length - index >= 2)
{
if (isFirst)
{
result = $"({firstTermVar} == {EqualityTerm(Name, index, 2, "ushort", "u")})";
}
else
{
result += delim + Term(Name, index, 2, "ushort", "u");
}
index += 2;
}
else
{
if (isFirst)
{
result = $"({firstTermVar} == {EqualityTerm(Name, index, 1, "byte", "u")})";
}
else
{
result += delim + Term(Name, index, 1, "byte", "u");
}
index += 1;
}
isFirst = false;
}
return result;
}
}
public string EqualIgnoreCaseBytesFirstTerm()
{
var result = "";
if (Name.Length >= 8)
{
result = Term(Name, 0, 8, "ulong", "uL");
}
else if (Name.Length >= 4)
{
result = Term(Name, 0, 4, "uint", "u");
}
else if (Name.Length >= 2)
{
result = Term(Name, 0, 2, "ushort", "u");
}
else
{
result = Term(Name, 0, 1, "byte", "u");
}
return result;
}
public string EqualIgnoreCaseBytesSecondTermOnwards()
{
var result = "";
var delim = "";
var index = 0;
var isFirst = true;
while (index != Name.Length)
{
if (Name.Length - index >= 8)
{
if (!isFirst)
{
result += delim + Term(Name, index, 8, "ulong", "uL");
}
index += 8;
}
else if (Name.Length - index >= 4)
{
if (!isFirst)
{
result += delim + Term(Name, index, 4, "uint", "u");
}
index += 4;
}
else if (Name.Length - index >= 2)
{
if (!isFirst)
{
result += delim + Term(Name, index, 2, "ushort", "u");
}
index += 2;
}
else
{
if (!isFirst)
{
result += delim + Term(Name, index, 1, "byte", "u");
}
index += 1;
}
if (isFirst)
{
isFirst = false;
}
else
{
delim = " && ";
}
}
return result;
}
}
public static string GeneratedFile()
{
var requestHeaders = RequestHeaders;
Debug.Assert(requestHeaders.Length <= 64);
Debug.Assert(requestHeaders.Max(x => x.Index) <= 62);
// 63 for responseHeaders as it steals one bit for Content-Length in CopyTo(ref MemoryPoolIterator output)
var responseHeaders = ResponseHeaders;
Debug.Assert(responseHeaders.Length <= 63);
Debug.Assert(responseHeaders.Count(x => x.Index == 63) == 1);
var responseTrailers = ResponseTrailers;
var loops = new[]
{
new
{
Headers = requestHeaders,
HeadersByLength = requestHeaders.GroupBy(x => x.Name.Length),
ClassName = "HttpRequestHeaders",
Bytes = default(byte[])
},
new
{
Headers = responseHeaders,
HeadersByLength = responseHeaders.GroupBy(x => x.Name.Length),
ClassName = "HttpResponseHeaders",
Bytes = responseHeaders.SelectMany(header => header.Bytes).ToArray()
},
new
{
Headers = responseTrailers,
HeadersByLength = responseTrailers.GroupBy(x => x.Name.Length),
ClassName = "HttpResponseTrailers",
Bytes = responseTrailers.SelectMany(header => header.Bytes).ToArray()
}
};
foreach (var loop in loops.Where(l => l.Bytes != null))
{
var offset = 0;
foreach (var header in loop.Headers)
{
header.BytesOffset = offset;
header.BytesCount += header.Bytes.Length;
offset += header.BytesCount;
}
}
return $@"// 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.Buffers;
using System.IO.Pipelines;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using Microsoft.Extensions.Primitives;
using Microsoft.Net.Http.Headers;
using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure;
namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http
{{
{Each(loops, loop => $@"
internal partial class {loop.ClassName}
{{{(loop.Bytes != null ?
$@"
private static ReadOnlySpan<byte> HeaderBytes => new byte[]
{{
{Each(loop.Bytes, b => $"{b},")}
}};"
: "")}
private HeaderReferences _headers;
{Each(loop.Headers.Where(header => header.ExistenceCheck), header => $@"
public bool Has{header.Identifier} => {header.TestBit()};")}
{Each(loop.Headers.Where(header => header.FastCount), header => $@"
public int {header.Identifier}Count => _headers._{header.Identifier}.Count;")}
{Each(loop.Headers, header => $@"
public StringValues Header{header.Identifier}
{{{(header.Identifier == "ContentLength" ? $@"
get
{{
StringValues value = default;
if (_contentLength.HasValue)
{{
value = new StringValues(HeaderUtilities.FormatNonNegativeInt64(_contentLength.Value));
}}
return value;
}}
set
{{
_contentLength = ParseContentLength(value);
}}" : $@"
get
{{
StringValues value = default;
if ({header.TestBit()})
{{
value = _headers._{header.Identifier};
}}
return value;
}}
set
{{
{header.SetBit()};
_headers._{header.Identifier} = value; {(header.EnhancedSetter == false ? "" : $@"
_headers._raw{header.Identifier} = null;")}
}}")}
}}")}
{Each(loop.Headers.Where(header => header.EnhancedSetter), header => $@"
public void SetRaw{header.Identifier}(StringValues value, byte[] raw)
{{
{header.SetBit()};
_headers._{header.Identifier} = value;
_headers._raw{header.Identifier} = raw;
}}")}
protected override int GetCountFast()
{{
return (_contentLength.HasValue ? 1 : 0 ) + BitCount(_bits) + (MaybeUnknown?.Count ?? 0);
}}
protected override bool TryGetValueFast(string key, out StringValues value)
{{
value = default;
switch (key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{{(header.Identifier == "ContentLength" ? @"
if (_contentLength.HasValue)
{
value = HeaderUtilities.FormatNonNegativeInt64(_contentLength.Value);
return true;
}
return false;" : $@"
if ({header.TestBit()})
{{
value = _headers._{header.Identifier};
return true;
}}
return false;")}
}}")}
}}
break;")}
}}
return MaybeUnknown?.TryGetValue(key, out value) ?? false;
}}
protected override void SetValueFast(string key, StringValues value)
{{{(loop.ClassName != "HttpRequestHeaders" ? @"
ValidateHeaderValueCharacters(value);" : "")}
switch (key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{{(header.Identifier == "ContentLength" ? $@"
_contentLength = ParseContentLength(value.ToString());" : $@"
{header.SetBit()};
_headers._{header.Identifier} = value;{(header.EnhancedSetter == false ? "" : $@"
_headers._raw{header.Identifier} = null;")}")}
return;
}}")}
}}
break;")}
}}
SetValueUnknown(key, value);
}}
protected override bool AddValueFast(string key, StringValues value)
{{{(loop.ClassName != "HttpRequestHeaders" ? @"
ValidateHeaderValueCharacters(value);" : "")}
switch (key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{{(header.Identifier == "ContentLength" ? $@"
if (!_contentLength.HasValue)
{{
_contentLength = ParseContentLength(value);
return true;
}}
return false;" : $@"
if ({header.TestNotBit()})
{{
{header.SetBit()};
_headers._{header.Identifier} = value;{(header.EnhancedSetter == false ? "" : $@"
_headers._raw{header.Identifier} = null;")}
return true;
}}
return false;")}
}}")}
}}
break;")}
}}
{(loop.ClassName == "HttpResponseHeaders" ? @"
ValidateHeaderNameCharacters(key);" : "")}
Unknown.Add(key, value);
// Return true, above will throw and exit for false
return true;
}}
protected override bool RemoveFast(string key)
{{
switch (key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{{(header.Identifier == "ContentLength" ? @"
if (_contentLength.HasValue)
{
_contentLength = null;
return true;
}
return false;" : $@"
if ({header.TestBit()})
{{
{header.ClearBit()};
_headers._{header.Identifier} = default(StringValues);{(header.EnhancedSetter == false ? "" : $@"
_headers._raw{header.Identifier} = null;")}
return true;
}}
return false;")}
}}")}
}}
break;")}
}}
return MaybeUnknown?.Remove(key) ?? false;
}}
{(loop.ClassName != "HttpRequestHeaders" ?
$@" protected override void ClearFast()
{{
MaybeUnknown?.Clear();
_contentLength = null;
var tempBits = _bits;
_bits = 0;
if(HttpHeaders.BitCount(tempBits) > 12)
{{
_headers = default(HeaderReferences);
return;
}}
{Each(loop.Headers.Where(header => header.Identifier != "ContentLength").OrderBy(h => !h.PrimaryHeader), header => $@"
if ({header.TestTempBit()})
{{
_headers._{header.Identifier} = default(StringValues);
if({header.TestNotTempBit()})
{{
return;
}}
tempBits &= ~{"0x" + (1L << header.Index).ToString("x")}L;
}}
")}
}}
" :
$@" private void Clear(long bitsToClear)
{{
var tempBits = bitsToClear;
{Each(loop.Headers.Where(header => header.Identifier != "ContentLength").OrderBy(h => !h.PrimaryHeader), header => $@"
if ({header.TestTempBit()})
{{
_headers._{header.Identifier} = default(StringValues);
if({header.TestNotTempBit()})
{{
return;
}}
tempBits &= ~{"0x" + (1L << header.Index).ToString("x")}L;
}}
")}
}}
")}
protected override bool CopyToFast(KeyValuePair<string, StringValues>[] array, int arrayIndex)
{{
if (arrayIndex < 0)
{{
return false;
}}
{Each(loop.Headers.Where(header => header.Identifier != "ContentLength"), header => $@"
if ({header.TestBit()})
{{
if (arrayIndex == array.Length)
{{
return false;
}}
array[arrayIndex] = new KeyValuePair<string, StringValues>(""{header.Name}"", _headers._{header.Identifier});
++arrayIndex;
}}")}
if (_contentLength.HasValue)
{{
if (arrayIndex == array.Length)
{{
return false;
}}
array[arrayIndex] = new KeyValuePair<string, StringValues>(""Content-Length"", HeaderUtilities.FormatNonNegativeInt64(_contentLength.Value));
++arrayIndex;
}}
((ICollection<KeyValuePair<string, StringValues>>)MaybeUnknown)?.CopyTo(array, arrayIndex);
return true;
}}
{(loop.ClassName == "HttpResponseHeaders" ? $@"
internal unsafe void CopyToFast(ref BufferWriter<PipeWriter> output)
{{
var tempBits = (ulong)_bits | (_contentLength.HasValue ? {"0x" + (1L << 63).ToString("x")}L : 0);
var next = 0;
var keyStart = 0;
var keyLength = 0;
ref readonly StringValues values = ref Unsafe.AsRef<StringValues>(null);
do
{{
switch (next)
{{{Each(loop.Headers.OrderBy(h => !h.PrimaryHeader).Select((h, i) => (Header: h, Index: i)), hi => $@"
case {hi.Index}: // Header: ""{hi.Header.Name}""
if ({hi.Header.TestTempBit()})
{{
tempBits ^= {"0x" + (1L << hi.Header.Index).ToString("x")}L;{(hi.Header.Identifier != "ContentLength" ? $@"{(hi.Header.EnhancedSetter == false ? $@"
values = ref _headers._{hi.Header.Identifier};
keyStart = {hi.Header.BytesOffset};
keyLength = {hi.Header.BytesCount};
next = {hi.Index + 1};
break; // OutputHeader" : $@"
if (_headers._raw{hi.Header.Identifier} != null)
{{
output.Write(_headers._raw{hi.Header.Identifier});
}}
else
{{
values = ref _headers._{hi.Header.Identifier};
keyStart = {hi.Header.BytesOffset};
keyLength = {hi.Header.BytesCount};
next = {hi.Index + 1};
break; // OutputHeader
}}")}" : $@"
output.Write(HeaderBytes.Slice({hi.Header.BytesOffset}, {hi.Header.BytesCount}));
output.WriteNumeric((ulong)ContentLength.Value);
if (tempBits == 0)
{{
return;
}}")}
}}
{(hi.Index + 1 < loop.Headers.Count() ? $"goto case {hi.Index + 1};" : "return;")}")}
default:
return;
}}
// OutputHeader
{{
var valueCount = values.Count;
var headerKey = HeaderBytes.Slice(keyStart, keyLength);
for (var i = 0; i < valueCount; i++)
{{
var value = values[i];
if (value != null)
{{
output.Write(headerKey);
output.WriteAsciiNoValidation(value);
}}
}}
}}
}} while (tempBits != 0);
}}" : "")}{(loop.ClassName == "HttpRequestHeaders" ? $@"
[MethodImpl(MethodImplOptions.AggressiveOptimization)]
public unsafe void Append(Span<byte> name, Span<byte> value)
{{
ref byte nameStart = ref MemoryMarshal.GetReference(name);
ref StringValues values = ref Unsafe.AsRef<StringValues>(null);
var flag = 0L;
// Does the name matched any ""known"" headers
{AppendSwitch(loop.Headers.GroupBy(x => x.Name.Length).OrderBy(x => x.Key))}
if (flag != 0)
{{
// Matched a known header
if ((_previousBits & flag) != 0)
{{
// Had a previous string for this header, mark it as used so we don't clear it OnHeadersComplete or consider it if we get a second header
_previousBits ^= flag;
// We will only reuse this header if there was only one previous header
if (values.Count == 1)
{{
var previousValue = values.ToString();
// Check lengths are the same, then if the bytes were converted to an ascii string if they would be the same.
// We do not consider Utf8 headers for reuse.
if (previousValue.Length == value.Length &&
StringUtilities.BytesOrdinalEqualsStringAndAscii(previousValue, value))
{{
// The previous string matches what the bytes would convert to, so we will just use that one.
_bits |= flag;
return;
}}
}}
}}
// We didn't have a previous matching header value, or have already added a header, so get the string for this value.
var valueStr = value.GetAsciiOrUTF8StringNonNullCharacters();
if ((_bits & flag) == 0)
{{
// We didn't already have a header set, so add a new one.
_bits |= flag;
values = new StringValues(valueStr);
}}
else
{{
// We already had a header set, so concatenate the new one.
values = AppendValue(values, valueStr);
}}
}}
else
{{
// The header was not one of the ""known"" headers.
// Convert value to string first, because passing two spans causes 8 bytes stack zeroing in
// this method with rep stosd, which is slower than necessary.
var valueStr = value.GetAsciiOrUTF8StringNonNullCharacters();
AppendUnknownHeaders(name, valueStr);
}}
}}" : "")}
private struct HeaderReferences
{{{Each(loop.Headers.Where(header => header.Identifier != "ContentLength"), header => @"
public StringValues _" + header.Identifier + ";")}
{Each(loop.Headers.Where(header => header.EnhancedSetter), header => @"
public byte[] _raw" + header.Identifier + ";")}
}}
public partial struct Enumerator
{{
// Compiled to Jump table
public bool MoveNext()
{{
switch (_next)
{{{Each(loop.Headers.Where(header => header.Identifier != "ContentLength"), header => $@"
case {header.Index}:
goto Header{header.Identifier};")}
{(!loop.ClassName.Contains("Trailers") ? $@"case {loop.Headers.Count() - 1}:
goto HeaderContentLength;" : "")}
default:
goto ExtraHeaders;
}}
{Each(loop.Headers.Where(header => header.Identifier != "ContentLength"), header => $@"
Header{header.Identifier}: // case {header.Index}
if ({header.TestBit()})
{{
_current = new KeyValuePair<string, StringValues>(""{header.Name}"", _collection._headers._{header.Identifier});
_next = {header.Index + 1};
return true;
}}")}
{(!loop.ClassName.Contains("Trailers") ? $@"HeaderContentLength: // case {loop.Headers.Count() - 1}
if (_collection._contentLength.HasValue)
{{
_current = new KeyValuePair<string, StringValues>(""Content-Length"", HeaderUtilities.FormatNonNegativeInt64(_collection._contentLength.Value));
_next = {loop.Headers.Count()};
return true;
}}" : "")}
ExtraHeaders:
if (!_hasUnknown || !_unknownEnumerator.MoveNext())
{{
_current = default(KeyValuePair<string, StringValues>);
return false;
}}
_current = _unknownEnumerator.Current;
return true;
}}
}}
}}
")}}}";
}
}
}