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1 | | -// ReSharper disable once CheckNamespace |
| 1 | +#if !NET |
| 2 | +using System.Diagnostics; |
| 3 | +using System.Diagnostics.CodeAnalysis; |
| 4 | +using System.Runtime.CompilerServices; |
| 5 | +using System.Runtime.InteropServices; |
| 6 | + |
| 7 | +// ReSharper disable once CheckNamespace |
2 | 8 | namespace System.Net.Sockets; |
3 | 9 |
|
4 | 10 | internal static class SocketExtensions |
5 | 11 | { |
6 | | -#if !NET |
7 | | - internal static ValueTask ConnectAsync(this Socket socket, EndPoint remoteEP, CancellationToken cancellationToken = default) |
| 12 | + internal static async ValueTask ConnectAsync(this Socket socket, EndPoint remoteEP, CancellationToken cancellationToken = default) |
8 | 13 | { |
9 | | - throw new NotImplementedException(); |
| 14 | + // this API is only used during handshake, *not* core IO, so: we're not concerned about alloc overhead |
| 15 | + using var args = new SocketAwaitableEventArgs(SocketFlags.None, cancellationToken); |
| 16 | + args.RemoteEndPoint = remoteEP; |
| 17 | + if (!socket.ConnectAsync(args)) |
| 18 | + { |
| 19 | + args.Complete(); |
| 20 | + } |
| 21 | + await args; |
10 | 22 | } |
11 | 23 |
|
12 | | - internal static ValueTask<int> SendAsync(this Socket socket, ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken = default) |
| 24 | + internal static async ValueTask<int> SendAsync(this Socket socket, ReadOnlyMemory<byte> buffer, SocketFlags socketFlags, CancellationToken cancellationToken = default) |
13 | 25 | { |
14 | | - throw new NotImplementedException(); |
| 26 | + // this API is only used during handshake, *not* core IO, so: we're not concerned about alloc overhead |
| 27 | + using var args = new SocketAwaitableEventArgs(socketFlags, cancellationToken); |
| 28 | + args.SetBuffer(buffer); |
| 29 | + if (!socket.SendAsync(args)) |
| 30 | + { |
| 31 | + args.Complete(); |
| 32 | + } |
| 33 | + return await args; |
15 | 34 | } |
16 | 35 |
|
17 | | - internal static ValueTask<int> ReceiveAsync(this Socket socket, ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken = default) |
| 36 | + internal static async ValueTask<int> ReceiveAsync(this Socket socket, Memory<byte> buffer, SocketFlags socketFlags, CancellationToken cancellationToken = default) |
18 | 37 | { |
19 | | - throw new NotImplementedException(); |
| 38 | + // this API is only used during handshake, *not* core IO, so: we're not concerned about alloc overhead |
| 39 | + using var args = new SocketAwaitableEventArgs(socketFlags, cancellationToken); |
| 40 | + args.SetBuffer(buffer); |
| 41 | + if (!socket.ReceiveAsync(args)) |
| 42 | + { |
| 43 | + args.Complete(); |
| 44 | + } |
| 45 | + return await args; |
| 46 | + } |
| 47 | + |
| 48 | + /// <summary> |
| 49 | + /// Awaitable SocketAsyncEventArgs, where awaiting the args yields either the BytesTransferred or throws the relevant socket exception, |
| 50 | + /// plus support for cancellation via <see cref="SocketError.TimedOut"/>. |
| 51 | + /// </summary> |
| 52 | + private sealed class SocketAwaitableEventArgs : SocketAsyncEventArgs, ICriticalNotifyCompletion, IDisposable |
| 53 | + { |
| 54 | + public new void Dispose() |
| 55 | + { |
| 56 | + cancelRegistration.Dispose(); |
| 57 | + base.Dispose(); |
| 58 | + } |
| 59 | + |
| 60 | + private CancellationTokenRegistration cancelRegistration; |
| 61 | + public SocketAwaitableEventArgs(SocketFlags socketFlags, CancellationToken cancellationToken) |
| 62 | + { |
| 63 | + SocketFlags = socketFlags; |
| 64 | + if (cancellationToken.CanBeCanceled) |
| 65 | + { |
| 66 | + cancellationToken.ThrowIfCancellationRequested(); |
| 67 | + cancelRegistration = cancellationToken.Register(Timeout); |
| 68 | + } |
| 69 | + } |
| 70 | + |
| 71 | + public void SetBuffer(ReadOnlyMemory<byte> buffer) |
| 72 | + { |
| 73 | + if (!MemoryMarshal.TryGetArray(buffer, out var segment)) ThrowNotSupported(); |
| 74 | + SetBuffer(segment.Array ?? [], segment.Offset, segment.Count); |
| 75 | + |
| 76 | + [DoesNotReturn] |
| 77 | + static void ThrowNotSupported() => throw new NotSupportedException("Only array-backed buffers are supported"); |
| 78 | + } |
| 79 | + |
| 80 | + public void Timeout() => Abort(SocketError.TimedOut); |
| 81 | + |
| 82 | + public void Abort(SocketError error) |
| 83 | + { |
| 84 | + _forcedError = error; |
| 85 | + OnCompleted(this); |
| 86 | + } |
| 87 | + |
| 88 | + private volatile SocketError _forcedError; // Success = 0, no field init required |
| 89 | + |
| 90 | + // ReSharper disable once InconsistentNaming |
| 91 | + private static readonly Action _callbackCompleted = () => { }; |
| 92 | + |
| 93 | + private Action? _callback; |
| 94 | + |
| 95 | + public SocketAwaitableEventArgs GetAwaiter() => this; |
| 96 | + |
| 97 | + /// <summary> |
| 98 | + /// Indicates whether the current operation is complete; used as part of "await". |
| 99 | + /// </summary> |
| 100 | + public bool IsCompleted => ReferenceEquals(_callback, _callbackCompleted); |
| 101 | + |
| 102 | + /// <summary> |
| 103 | + /// Gets the result of the async operation is complete; used as part of "await". |
| 104 | + /// </summary> |
| 105 | + public int GetResult() |
| 106 | + { |
| 107 | + Debug.Assert(ReferenceEquals(_callback, _callbackCompleted)); |
| 108 | + |
| 109 | + _callback = null; |
| 110 | + |
| 111 | + var error = _forcedError; |
| 112 | + if (error is SocketError.Success) error = SocketError; |
| 113 | + if (error is not SocketError.Success) ThrowSocketException(error); |
| 114 | + |
| 115 | + return BytesTransferred; |
| 116 | + |
| 117 | + static void ThrowSocketException(SocketError e) => throw new SocketException((int)e); |
| 118 | + } |
| 119 | + |
| 120 | + /// <summary> |
| 121 | + /// Schedules a continuation for this operation; used as part of "await". |
| 122 | + /// </summary> |
| 123 | + public void OnCompleted(Action continuation) |
| 124 | + { |
| 125 | + if (ReferenceEquals(Volatile.Read(ref _callback), _callbackCompleted) |
| 126 | + || ReferenceEquals(Interlocked.CompareExchange(ref _callback, continuation, null), _callbackCompleted)) |
| 127 | + { |
| 128 | + // this is the rare "kinda already complete" case; push to worker to prevent possible stack dive, |
| 129 | + // but prefer the custom scheduler when possible |
| 130 | + RunOnThreadPool(continuation); |
| 131 | + } |
| 132 | + } |
| 133 | + |
| 134 | + /// <summary> |
| 135 | + /// Schedules a continuation for this operation; used as part of "await". |
| 136 | + /// </summary> |
| 137 | + public void UnsafeOnCompleted(Action continuation) => OnCompleted(continuation); |
| 138 | + |
| 139 | + /// <summary> |
| 140 | + /// Marks the operation as complete - this should be invoked whenever a SocketAsyncEventArgs operation returns false. |
| 141 | + /// </summary> |
| 142 | + public void Complete() => OnCompleted(this); |
| 143 | + |
| 144 | + private static void RunOnThreadPool(Action action) |
| 145 | + => ThreadPool.QueueUserWorkItem(static state => ((Action)state).Invoke(), action); |
| 146 | + |
| 147 | + /// <summary> |
| 148 | + /// Invoked automatically when an operation completes asynchronously. |
| 149 | + /// </summary> |
| 150 | + protected override void OnCompleted(SocketAsyncEventArgs e) |
| 151 | + { |
| 152 | + var continuation = Interlocked.Exchange(ref _callback, _callbackCompleted); |
| 153 | + if (continuation is not null) |
| 154 | + { |
| 155 | + // continue on the thread-pool |
| 156 | + RunOnThreadPool(continuation); |
| 157 | + } |
| 158 | + } |
20 | 159 | } |
21 | | -#endif |
22 | 160 | } |
| 161 | +#endif |
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