aspnetcore/test/Microsoft.AspNetCore.Routin.../Matchers/DfaMatcher.cs

93 lines
2.8 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.Threading.Tasks;
using Microsoft.AspNetCore.Http;
namespace Microsoft.AspNetCore.Routing.Matchers
{
internal class DfaMatcher : Matcher
{
private readonly State[] _states;
public DfaMatcher(State[] states)
{
_states = states;
}
public unsafe override Task MatchAsync(HttpContext httpContext, IEndpointFeature feature)
{
if (httpContext == null)
{
throw new ArgumentNullException(nameof(httpContext));
}
if (feature == null)
{
throw new ArgumentNullException(nameof(feature));
}
var states = _states;
var current = 0;
var path = httpContext.Request.Path.Value;
var buffer = stackalloc PathSegment[32];
var count = FastPathTokenizer.Tokenize(path, buffer, 32);
for (var i = 0; i < count; i++)
{
current = states[current].Transitions.GetDestination(path, buffer[i]);
}
var matches = new List<(Endpoint, RouteValueDictionary)>();
var candidates = states[current].Matches;
for (var i = 0; i < candidates.Length; i++)
{
var values = new RouteValueDictionary();
var parameters = candidates[i].Parameters;
if (parameters != null)
{
for (var j = 0; j < parameters.Length; j++)
{
var parameter = parameters[j];
if (parameter != null && buffer[j].Length == 0)
{
goto notmatch;
}
else if (parameter != null)
{
var value = path.Substring(buffer[j].Start, buffer[j].Length);
values.Add(parameter, value);
}
}
}
matches.Add((candidates[i].Endpoint, values));
notmatch: ;
}
feature.Endpoint = matches.Count == 0 ? null : matches[0].Item1;
feature.Values = matches.Count == 0 ? null : matches[0].Item2;
return Task.CompletedTask;
}
public struct State
{
public bool IsAccepting;
public Candidate[] Matches;
public JumpTable Transitions;
}
public struct Candidate
{
public Endpoint Endpoint;
public string[] Parameters;
}
}
}