341 lines
10 KiB
C#
341 lines
10 KiB
C#
/*************************************************************************
|
|
* ModernUO *
|
|
* Copyright 2019-2020 - ModernUO Development Team *
|
|
* Email: hi@modernuo.com *
|
|
* File: Pipe.cs *
|
|
* *
|
|
* This program is free software: you can redistribute it and/or modify *
|
|
* it under the terms of the GNU General Public License as published by *
|
|
* the Free Software Foundation, either version 3 of the License, or *
|
|
* (at your option) any later version. *
|
|
* *
|
|
* You should have received a copy of the GNU General Public License *
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>. *
|
|
*************************************************************************/
|
|
|
|
using System;
|
|
using System.Buffers;
|
|
using System.Runtime.CompilerServices;
|
|
using System.Threading;
|
|
|
|
namespace Server.Network
|
|
{
|
|
public interface IPipeTask<T> : INotifyCompletion
|
|
{
|
|
public IPipeTask<T> GetAwaiter();
|
|
|
|
public bool IsCompleted { get; }
|
|
|
|
public T GetResult();
|
|
|
|
public void OnCompleted(Action continuation);
|
|
}
|
|
|
|
public class Pipe<T>
|
|
{
|
|
public class PipeWriter<T>
|
|
{
|
|
private readonly Pipe<T> _pipe;
|
|
|
|
public PipeWriter(Pipe<T> pipe) => _pipe = pipe;
|
|
|
|
public bool GetAvailable(ArraySegment<T>[] segments)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
if (read <= write)
|
|
{
|
|
var readZero = read == 0;
|
|
var sz = _pipe.Size - write - (readZero ? 1 : 0);
|
|
|
|
segments[0] = sz == 0 ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, (int)write, (int)sz);
|
|
segments[1] = readZero ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, 0, (int)read - 1);
|
|
}
|
|
else
|
|
{
|
|
var sz = read - write - 1;
|
|
|
|
segments[0] = sz == 0 ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, (int)write, (int)sz);
|
|
segments[1] = ArraySegment<T>.Empty;
|
|
}
|
|
|
|
return !_pipe._closed;
|
|
}
|
|
|
|
public bool GetAvailable(out CircularBuffer<T> buffer)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
Span<T> first;
|
|
Span<T> second;
|
|
|
|
if (read <= write)
|
|
{
|
|
var readZero = read == 0;
|
|
var sz = _pipe.Size - write - (readZero ? 1 : 0);
|
|
|
|
first = sz == 0 ? Span<T>.Empty : _pipe._buffer.AsSpan((int)write, (int)sz);
|
|
second = readZero ? Span<T>.Empty : _pipe._buffer.AsSpan(0, (int)read - 1);
|
|
}
|
|
else
|
|
{
|
|
var sz = read - write - 1;
|
|
|
|
first = sz == 0 ? Span<T>.Empty : _pipe._buffer.AsSpan((int)write, (int)sz);
|
|
second = Span<T>.Empty;
|
|
}
|
|
|
|
buffer = new CircularBuffer<T>(first, second);
|
|
|
|
return !_pipe._closed;
|
|
}
|
|
|
|
public void Advance(uint count)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
if (count == 0)
|
|
{
|
|
return;
|
|
}
|
|
|
|
if (count > _pipe.Size - 1)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
if (read <= write)
|
|
{
|
|
if (count > read + _pipe.Size - write - 1)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
var sz = Math.Min(count, _pipe.Size - write);
|
|
|
|
write += sz;
|
|
if (write > _pipe.Size - 1)
|
|
{
|
|
write = 0;
|
|
}
|
|
count -= sz;
|
|
|
|
if (count > 0)
|
|
{
|
|
if (count >= read)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
write = count;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (count > read - write - 1)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
write += count;
|
|
}
|
|
|
|
// It's never valid to advance the write pointer to become equal to
|
|
// the read pointer. Check that here.
|
|
if (write == read)
|
|
{
|
|
throw new InvalidOperationException("Write index equals read index after advance");
|
|
}
|
|
|
|
_pipe._writeIdx = write;
|
|
}
|
|
|
|
public void Close()
|
|
{
|
|
_pipe._closed = true;
|
|
|
|
Flush();
|
|
}
|
|
|
|
public void Flush()
|
|
{
|
|
var waiting = _pipe._awaitBeginning;
|
|
|
|
if (!waiting)
|
|
{
|
|
return;
|
|
}
|
|
|
|
Action continuation;
|
|
|
|
do
|
|
{
|
|
continuation = _pipe._readerContinuation;
|
|
} while (continuation == null);
|
|
|
|
_pipe._readerContinuation = null;
|
|
_pipe._awaitBeginning = false;
|
|
|
|
ThreadPool.UnsafeQueueUserWorkItem(state => continuation(), true);
|
|
}
|
|
}
|
|
|
|
public class PipeReader<T> : IPipeTask<PipeReader<T>>
|
|
{
|
|
private readonly Pipe<T> _pipe;
|
|
|
|
internal PipeReader(Pipe<T> pipe) => _pipe = pipe;
|
|
|
|
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
|
public uint GetAvailable()
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
if (read <= write)
|
|
{
|
|
return write - read;
|
|
}
|
|
|
|
return write + _pipe.Size - read;
|
|
}
|
|
|
|
public bool TryRead(out CircularBuffer<T> buffer)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
Span<T> first;
|
|
Span<T> second;
|
|
|
|
if (read <= write)
|
|
{
|
|
first = write - read == 0 ? Span<T>.Empty : _pipe._buffer.AsSpan((int)read, (int)(write - read));
|
|
second = Span<T>.Empty;
|
|
}
|
|
else
|
|
{
|
|
first = _pipe.Size - read == 0 ? Span<T>.Empty : _pipe._buffer.AsSpan((int)read, (int)(_pipe.Size - read));
|
|
second = write == 0 ? Span<T>.Empty : _pipe._buffer.AsSpan(0, (int)write);
|
|
}
|
|
|
|
buffer = new CircularBuffer<T>(first, second);
|
|
return !_pipe._closed;
|
|
}
|
|
|
|
public bool TryRead(ArraySegment<T>[] segments)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
if (read <= write)
|
|
{
|
|
segments[0] = write - read == 0 ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, (int)read, (int)(write - read));
|
|
segments[1] = ArraySegment<T>.Empty;
|
|
}
|
|
else
|
|
{
|
|
segments[0] = _pipe.Size - read == 0 ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, (int)read, (int)(_pipe.Size - read));
|
|
segments[1] = write == 0 ? ArraySegment<T>.Empty : new ArraySegment<T>(_pipe._buffer, 0, (int)write);
|
|
}
|
|
|
|
return !_pipe._closed;
|
|
}
|
|
|
|
public void Advance(uint count)
|
|
{
|
|
var read = _pipe._readIdx;
|
|
var write = _pipe._writeIdx;
|
|
|
|
if (read <= write)
|
|
{
|
|
if (count > write - read)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
read += count;
|
|
}
|
|
else
|
|
{
|
|
var sz = Math.Min(count, _pipe.Size - read);
|
|
|
|
read += sz;
|
|
if (read > _pipe.Size - 1)
|
|
{
|
|
read = 0;
|
|
}
|
|
count -= sz;
|
|
|
|
if (count > 0)
|
|
{
|
|
if (count > write)
|
|
{
|
|
throw new InvalidOperationException();
|
|
}
|
|
|
|
read = count;
|
|
}
|
|
}
|
|
|
|
_pipe._readIdx = read;
|
|
}
|
|
|
|
#region Awaitable
|
|
|
|
// The following makes it possible to await the reader. Do not use any of this directly.
|
|
|
|
public IPipeTask<PipeReader<T>> GetAwaiter() => this;
|
|
|
|
public bool IsCompleted
|
|
{
|
|
get
|
|
{
|
|
if (GetAvailable() > 0)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
_pipe._awaitBeginning = true;
|
|
return false;
|
|
}
|
|
}
|
|
|
|
public PipeReader<T> GetResult() => this;
|
|
|
|
public void OnCompleted(Action continuation) => _pipe._readerContinuation = continuation;
|
|
|
|
#endregion
|
|
}
|
|
|
|
private readonly T[] _buffer;
|
|
private volatile uint _writeIdx;
|
|
private volatile uint _readIdx;
|
|
private bool _closed;
|
|
|
|
public PipeWriter<T> Writer { get; }
|
|
public PipeReader<T> Reader { get; }
|
|
|
|
public uint Size => (uint)_buffer.Length;
|
|
|
|
public Pipe(T[] buf)
|
|
{
|
|
_buffer = buf;
|
|
_writeIdx = 0;
|
|
_readIdx = 0;
|
|
_closed = false;
|
|
|
|
Writer = new PipeWriter<T>(this);
|
|
Reader = new PipeReader<T>(this);
|
|
}
|
|
|
|
#region Awaitable
|
|
private volatile bool _awaitBeginning;
|
|
private volatile Action _readerContinuation;
|
|
|
|
#endregion
|
|
}
|
|
}
|