Ryujinx/Ryujinx.Common/SystemInterop/UnixStream.cs

156 lines
3.8 KiB
C#
Raw Normal View History

using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.Versioning;
namespace Ryujinx.Common.SystemInterop
{
[SupportedOSPlatform("linux")]
[SupportedOSPlatform("macos")]
public partial class UnixStream : Stream, IDisposable
{
private const int InvalidFd = -1;
private int _fd;
[LibraryImport("libc", SetLastError = true)]
private static partial long read(int fd, IntPtr buf, ulong count);
[LibraryImport("libc", SetLastError = true)]
private static partial long write(int fd, IntPtr buf, ulong count);
[LibraryImport("libc", SetLastError = true)]
private static partial int close(int fd);
public UnixStream(int fd)
{
if (InvalidFd == fd)
{
throw new ArgumentException("Invalid file descriptor");
}
_fd = fd;
CanRead = read(fd, IntPtr.Zero, 0) != -1;
CanWrite = write(fd, IntPtr.Zero, 0) != -1;
}
~UnixStream()
{
Close();
}
public override bool CanRead { get; }
public override bool CanWrite { get; }
public override bool CanSeek => false;
public override long Length => throw new NotSupportedException();
public override long Position
{
get => throw new NotSupportedException();
set => throw new NotSupportedException();
}
public override void Flush()
{
}
public override unsafe int Read([In, Out] byte[] buffer, int offset, int count)
{
if (offset < 0 || offset > (buffer.Length - count) || count < 0)
{
throw new ArgumentOutOfRangeException();
}
if (buffer.Length == 0)
{
return 0;
}
long r = 0;
fixed (byte* buf = &buffer[offset])
{
do
{
r = read(_fd, (IntPtr)buf, (ulong)count);
} while (ShouldRetry(r));
}
return (int)r;
}
public override unsafe void Write(byte[] buffer, int offset, int count)
{
if (offset < 0 || offset > (buffer.Length - count) || count < 0)
{
throw new ArgumentOutOfRangeException();
}
if (buffer.Length == 0)
{
return;
}
fixed (byte* buf = &buffer[offset])
{
long r = 0;
do {
r = write(_fd, (IntPtr)buf, (ulong)count);
} while (ShouldRetry(r));
}
}
public override long Seek(long offset, SeekOrigin origin)
{
throw new NotSupportedException();
}
public override void SetLength(long value)
{
throw new NotSupportedException();
}
public override void Close()
{
if (_fd == InvalidFd)
{
return;
}
Flush();
int r;
do {
r = close(_fd);
} while (ShouldRetry(r));
_fd = InvalidFd;
}
void IDisposable.Dispose()
{
Close();
}
private bool ShouldRetry(long r)
{
if (r == -1)
{
const int eintr = 4;
int errno = Marshal.GetLastPInvokeError();
if (errno == eintr)
{
return true;
}
throw new SystemException($"Operation failed with error 0x{errno:X}");
}
return false;
}
}
}