aspnetcore/tools/Microsoft.AspNet.Server.Kes.../KnownHeaders.cs

419 lines
14 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Dnx.Compilation.CSharp;
namespace Microsoft.AspNet.Server.Kestrel.GeneratedCode
{
// This project can output the Class library as a NuGet Package.
// To enable this option, right-click on the project and select the Properties menu item. In the Build tab select "Produce outputs on build".
public class KnownHeaders : ICompileModule
{
static string Each<T>(IEnumerable<T> values, Func<T, string> formatter)
{
return values.Select(formatter).Aggregate((a, b) => a + b);
}
class KnownHeader
{
public string Name { get; set; }
public int Index { get; set; }
public string Identifier => Name.Replace("-", "");
public string TestBit() => $"((_bits & {1L << Index}L) != 0)";
public string SetBit() => $"_bits |= {1L << Index}L";
public string ClearBit() => $"_bits &= ~{1L << Index}L";
public string EqualIgnoreCaseBytes()
{
var result = "";
var delim = "";
var index = 0;
while (index != Name.Length)
{
if (Name.Length - index >= 8)
{
result += delim + Term(Name, index, 8, "pUL", "uL");
index += 8;
}
else if (Name.Length - index >= 4)
{
result += delim + Term(Name, index, 4, "pUI", "u");
index += 4;
}
else if (Name.Length - index >= 2)
{
result += delim + Term(Name, index, 2, "pUS", "u");
index += 2;
}
else
{
result += delim + Term(Name, index, 1, "pUB", "u");
index += 1;
}
delim = " && ";
}
return $"({result})";
}
protected string Term(string name, int offset, int count, string array, string suffix)
{
ulong mask = 0;
ulong 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);
}
return $"(({array}[{offset / count}] & {mask}{suffix}) == {comp}{suffix})";
}
}
public virtual void BeforeCompile(BeforeCompileContext context)
{
var syntaxTree = Microsoft.CodeAnalysis.CSharp.CSharpSyntaxTree.ParseText(GeneratedFile());
context.Compilation = context.Compilation.AddSyntaxTrees(syntaxTree);
}
public static string GeneratedFile()
{
var commonHeaders = new[]
{
"Cache-Control",
"Connection",
"Date",
"Keep-Alive",
"Pragma",
"Trailer",
"Transfer-Encoding",
"Upgrade",
"Via",
"Warning",
"Allow",
"Content-Length",
"Content-Type",
"Content-Encoding",
"Content-Language",
"Content-Location",
"Content-MD5",
"Content-Range",
"Expires",
"Last-Modified"
};
var 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",
}).Select((header, index) => new KnownHeader
{
Name = header,
Index = index
});
var responseHeaders = commonHeaders.Concat(new[]
{
"Accept-Ranges",
"Age",
"ETag",
"Location",
"Proxy-Autheticate",
"Retry-After",
"Server",
"Set-Cookie",
"Vary",
"WWW-Authenticate",
}).Select((header, index) => new KnownHeader
{
Name = header,
Index = index
});
var loops = new[]
{
new
{
Headers = requestHeaders,
HeadersByLength = requestHeaders.GroupBy(x => x.Name.Length),
ClassName = "FrameRequestHeaders"
},
new
{
Headers = responseHeaders,
HeadersByLength = responseHeaders.GroupBy(x => x.Name.Length),
ClassName = "FrameResponseHeaders"
}
};
return $@"
using System;
using System.Collections.Generic;
namespace Microsoft.AspNet.Server.Kestrel.Http
{{
public partial class FrameResponseHeaders
{{
public FrameResponseHeaders()
{{
_Server = new[] {{ ""Kestrel"" }};
_Date = new[] {{ DateTime.UtcNow.ToString(""r"") }};
_bits = {
1L << responseHeaders.First(header => header.Name == "Server").Index |
1L << responseHeaders.First(header => header.Name == "Date").Index
}L;
}}
}}
{Each(loops, loop => $@"
public partial class {loop.ClassName}
{{
long _bits = 0;
{Each(loop.Headers, header => @"
string[] _" + header.Identifier + ";")}
protected override int GetCountFast()
{{
var count = MaybeUnknown?.Count ?? 0;
{Each(loop.Headers, header => $@"
if ({header.TestBit()})
{{
++count;
}}
")}
return count;
}}
protected override string[] GetValueFast(string key)
{{
switch(key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{
if ({header.TestBit()})
{{
return _{header.Identifier};
}}
else
{{
throw new System.Collections.Generic.KeyNotFoundException();
}}
}}
")}}}
break;
")}}}
if (MaybeUnknown == null)
{{
throw new System.Collections.Generic.KeyNotFoundException();
}}
return MaybeUnknown[key];
}}
protected override bool TryGetValueFast(string key, out string[] value)
{{
switch(key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{
if ({header.TestBit()})
{{
value = _{header.Identifier};
return true;
}}
else
{{
value = null;
return false;
}}
}}
")}}}
break;
")}}}
value = null;
return MaybeUnknown?.TryGetValue(key, out value) ?? false;
}}
protected override void SetValueFast(string key, string[] value)
{{
switch(key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{
{header.SetBit()};
_{header.Identifier} = value;
return;
}}
")}}}
break;
")}}}
Unknown[key] = value;
}}
protected override void AddValueFast(string key, string[] value)
{{
switch(key.Length)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if (""{header.Name}"".Equals(key, StringComparison.OrdinalIgnoreCase))
{{
if ({header.TestBit()})
{{
throw new ArgumentException(""An item with the same key has already been added."");
}}
{header.SetBit()};
_{header.Identifier} = value;
return;
}}
")}}}
break;
")}}}
Unknown.Add(key, value);
}}
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))
{{
if ({header.TestBit()})
{{
{header.ClearBit()};
return true;
}}
else
{{
return false;
}}
}}
")}}}
break;
")}}}
return MaybeUnknown?.Remove(key) ?? false;
}}
protected override void ClearFast()
{{
_bits = 0;
MaybeUnknown?.Clear();
}}
protected override void CopyToFast(KeyValuePair<string, string[]>[] array, int arrayIndex)
{{
if (arrayIndex < 0)
{{
throw new ArgumentException();
}}
{Each(loop.Headers, header => $@"
if ({header.TestBit()})
{{
if (arrayIndex == array.Length)
{{
throw new ArgumentException();
}}
array[arrayIndex] = new KeyValuePair<string, string[]>(""{header.Name}"", _{header.Identifier});
++arrayIndex;
}}
")}
((ICollection<KeyValuePair<string, string[]>>)MaybeUnknown)?.CopyTo(array, arrayIndex);
}}
public unsafe void Append(byte[] keyBytes, int keyOffset, int keyLength, string value)
{{
fixed(byte* ptr = keyBytes) {{ var pUB = ptr + keyOffset; var pUL = (ulong*)pUB; var pUI = (uint*)pUB; var pUS = (ushort*)pUB;
switch(keyLength)
{{{Each(loop.HeadersByLength, byLength => $@"
case {byLength.Key}:
{{{Each(byLength, header => $@"
if ({header.EqualIgnoreCaseBytes()})
{{
if ({header.TestBit()})
{{
_{header.Identifier} = AppendValue(_{header.Identifier}, value);
}}
else
{{
{header.SetBit()};
_{header.Identifier} = new[] {{value}};
}}
return;
}}
")}}}
break;
")}}}}}
var key = System.Text.Encoding.ASCII.GetString(keyBytes, keyOffset, keyLength);
string[] existing;
Unknown[key] = Unknown.TryGetValue(key, out existing) ? AppendValue(existing, value) : new[] {{value}};
}}
public partial struct Enumerator
{{
public bool MoveNext()
{{
switch (_state)
{{
{Each(loop.Headers, header => $@"
case {header.Index}:
goto state{header.Index};
")}
default:
goto state_default;
}}
{Each(loop.Headers, header => $@"
state{header.Index}:
if ({header.TestBit()})
{{
_current = new KeyValuePair<string, string[]>(""{header.Name}"", _collection._{header.Identifier});
_state = {header.Index + 1};
return true;
}}
")}
state_default:
if (!_hasUnknown || !_unknownEnumerator.MoveNext())
{{
_current = default(KeyValuePair<string, string[]>);
return false;
}}
_current = _unknownEnumerator.Current;
return true;
}}
}}
}}
")}}}
";
}
public virtual void AfterCompile(AfterCompileContext context)
{
}
}
}