protected override void ReleaseUnmanagedResources()
{
if (!IsInvalid)
{
Unistd.close(_fd);
}
base.ReleaseUnmanagedResources();
}
private void Dispose(bool disposing)
{
if (_isDisposed)
{
return;
}
if (!IsInvalid)
{
Unistd.close(_fd);
}
_isDisposed = true;
}
public static bool IsElevatedUser()
{
if (IsWindows())
{
#if NETFRAMEWORK
var identity = System.Security.Principal.WindowsIdentity.GetCurrent();
var principal = new System.Security.Principal.WindowsPrincipal(identity);
return(principal.IsInRole(System.Security.Principal.WindowsBuiltInRole.Administrator));
#endif
}
else if (IsPosix())
{
return(Unistd.geteuid() == 0);
}
return(false);
}
/// <summary>
/// Write <paramref name="size"/> number of bytes from the buffer <paramref name="buf"/> to the file.
/// </summary>
/// <param name="buf">Buffer into which to read bytes will be placed.</param>
/// <param name="size">Number of bytes from buffer <paramref name="buf"/> to write.</param>
/// <returns>Number of bytes actually written. A value of -1 indicates failure.</returns>
public int Write(byte[] buf, int size)
{
ThrowIfDisposed();
ThrowIfInvalid();
return(Unistd.write(_fd, buf, size));
}
/// <summary>
/// Read <paramref name="count"/> number of bytes into the buffer <paramref name="buf"/> from the file.
/// </summary>
/// <param name="buf">Buffer into which to read bytes will be placed.</param>
/// <param name="count">Maximum number of bytes to read.</param>
/// <returns>Number of bytes actually read. A value of -1 indicates failure.</returns>
public int Read(byte[] buf, int count)
{
ThrowIfDisposed();
ThrowIfInvalid();
return(Unistd.read(_fd, buf, count));
}
private string Prompt(string prompt, bool echo)
{
using (var fd = new PosixFileDescriptor(TtyDeviceName, OpenFlags.O_RDWR))
{
if (fd.IsInvalid)
{
Trace.WriteLine("Not a TTY, abandoning prompt.");
return(null);
}
fd.Write($"{prompt}: ");
var sb = new StringBuilder();
using (CreateTtyContext(fd, echo))
{
var readBuf = new byte[1];
bool eol = false;
while (!eol)
{
int nr;
// Read one byte at a time
if ((nr = fd.Read(readBuf, 1)) != 1)
{
// Either we reached end of file or an error occured.
// We don't care which so let's just trace and terminate further reading.
Trace.WriteLine($"Exiting POSIX terminal prompt read-loop unexpectedly (nr={nr})");
eol = true;
break;
}
int c = readBuf[0];
switch (c)
{
case 3: // CTRL + C
// Since `read` is a blocking call we must manually raise the SIGINT signal
// when the user types CTRL+C into the terminal window.
int pid = Unistd.getpid();
Trace.WriteLine($"Intercepted SIGINT during terminal prompt read-loop - sending SIGINT to self (pid={pid})");
Signal.kill(pid, Signal.SIGINT);
break;
case '\n':
eol = true;
// Only need to echo the newline to move the terminal cursor down when
// echo is disabled. When echo is enabled the newline is written for us.
if (!echo)
{
fd.Write("\n");
}
break;
case '\b':
case DeleteChar:
if (sb.Length > 0)
{
sb.Remove(sb.Length - 1, 1);
fd.Write("\b \b");
}
break;
default:
sb.Append((char)c);
break;
}
}
return(sb.ToString());
}
}
}
