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// Common functions that are unfortunately missing on illumos and
// Solaris, but often needed by other crates.
use unix::solarish::*;
const PTEM: &[u8] = b"ptem\0";
const LDTERM: &[u8] = b"ldterm\0";
pub unsafe fn cfmakeraw(termios: *mut ::termios) {
(*termios).c_iflag &=
!(IMAXBEL | IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
(*termios).c_oflag &= !OPOST;
(*termios).c_lflag &= !(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
(*termios).c_cflag &= !(CSIZE | PARENB);
(*termios).c_cflag |= CS8;
// By default, most software expects a pending read to block until at
// least one byte becomes available. As per termio(7I), this requires
// setting the MIN and TIME parameters appropriately.
//
// As a somewhat unfortunate artefact of history, the MIN and TIME slots
// in the control character array overlap with the EOF and EOL slots used
// for canonical mode processing. Because the EOF character needs to be
// the ASCII EOT value (aka Control-D), it has the byte value 4. When
// switching to raw mode, this is interpreted as a MIN value of 4; i.e.,
// reads will block until at least four bytes have been input.
//
// Other platforms with a distinct MIN slot like Linux and FreeBSD appear
// to default to a MIN value of 1, so we'll force that value here:
(*termios).c_cc[VMIN] = 1;
(*termios).c_cc[VTIME] = 0;
}
pub unsafe fn cfsetspeed(termios: *mut ::termios, speed: ::speed_t) -> ::c_int {
// Neither of these functions on illumos or Solaris actually ever
// return an error
::cfsetispeed(termios, speed);
::cfsetospeed(termios, speed);
0
}
unsafe fn bail(fdm: ::c_int, fds: ::c_int) -> ::c_int {
let e = *___errno();
if fds >= 0 {
::close(fds);
}
if fdm >= 0 {
::close(fdm);
}
*___errno() = e;
return -1;
}
pub unsafe fn openpty(
amain: *mut ::c_int,
asubord: *mut ::c_int,
name: *mut ::c_char,
termp: *const termios,
winp: *const ::winsize,
) -> ::c_int {
// Open the main pseudo-terminal device, making sure not to set it as the
// controlling terminal for this process:
let fdm = ::posix_openpt(O_RDWR | O_NOCTTY);
if fdm < 0 {
return -1;
}
// Set permissions and ownership on the subordinate device and unlock it:
if ::grantpt(fdm) < 0 || ::unlockpt(fdm) < 0 {
return bail(fdm, -1);
}
// Get the path name of the subordinate device:
let subordpath = ::ptsname(fdm);
if subordpath.is_null() {
return bail(fdm, -1);
}
// Open the subordinate device without setting it as the controlling
// terminal for this process:
let fds = ::open(subordpath, O_RDWR | O_NOCTTY);
if fds < 0 {
return bail(fdm, -1);
}
// Check if the STREAMS modules are already pushed:
let setup = ::ioctl(fds, I_FIND, LDTERM.as_ptr());
if setup < 0 {
return bail(fdm, fds);
} else if setup == 0 {
// The line discipline is not present, so push the appropriate STREAMS
// modules for the subordinate device:
if ::ioctl(fds, I_PUSH, PTEM.as_ptr()) < 0 || ::ioctl(fds, I_PUSH, LDTERM.as_ptr()) < 0 {
return bail(fdm, fds);
}
}
// If provided, set the terminal parameters:
if !termp.is_null() && ::tcsetattr(fds, TCSAFLUSH, termp) != 0 {
return bail(fdm, fds);
}
// If provided, set the window size:
if !winp.is_null() && ::ioctl(fds, TIOCSWINSZ, winp) < 0 {
return bail(fdm, fds);
}
// If the caller wants the name of the subordinate device, copy it out.
//
// Note that this is a terrible interface: there appears to be no standard
// upper bound on the copy length for this pointer. Nobody should pass
// anything but NULL here, preferring instead to use ptsname(3C) directly.
if !name.is_null() {
::strcpy(name, subordpath);
}
*amain = fdm;
*asubord = fds;
0
}
pub unsafe fn forkpty(
amain: *mut ::c_int,
name: *mut ::c_char,
termp: *const termios,
winp: *const ::winsize,
) -> ::pid_t {
let mut fds = -1;
if openpty(amain, &mut fds, name, termp, winp) != 0 {
return -1;
}
let pid = ::fork();
if pid < 0 {
return bail(*amain, fds);
} else if pid > 0 {
// In the parent process, we close the subordinate device and return the
// process ID of the new child:
::close(fds);
return pid;
}
// The rest of this function executes in the child process.
// Close the main side of the pseudo-terminal pair:
::close(*amain);
// Use TIOCSCTTY to set the subordinate device as our controlling
// terminal. This will fail (with ENOTTY) if we are not the leader in
// our own session, so we call setsid() first. Finally, arrange for
// the pseudo-terminal to occupy the standard I/O descriptors.
if ::setsid() < 0
|| ::ioctl(fds, TIOCSCTTY, 0) < 0
|| ::dup2(fds, 0) < 0
|| ::dup2(fds, 1) < 0
|| ::dup2(fds, 2) < 0
{
// At this stage there are no particularly good ways to handle failure.
// Exit as abruptly as possible, using _exit() to avoid messing with any
// state still shared with the parent process.
::_exit(EXIT_FAILURE);
}
// Close the inherited descriptor, taking care to avoid closing the standard
// descriptors by mistake:
if fds > 2 {
::close(fds);
}
0
}
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