diff options
Diffstat (limited to 'vendor/rustix/src/backend/linux_raw/termios')
-rw-r--r-- | vendor/rustix/src/backend/linux_raw/termios/mod.rs | 1 | ||||
-rw-r--r-- | vendor/rustix/src/backend/linux_raw/termios/syscalls.rs | 330 |
2 files changed, 331 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/termios/mod.rs b/vendor/rustix/src/backend/linux_raw/termios/mod.rs new file mode 100644 index 0000000..ef944f0 --- /dev/null +++ b/vendor/rustix/src/backend/linux_raw/termios/mod.rs @@ -0,0 +1 @@ +pub(crate) mod syscalls; diff --git a/vendor/rustix/src/backend/linux_raw/termios/syscalls.rs b/vendor/rustix/src/backend/linux_raw/termios/syscalls.rs new file mode 100644 index 0000000..5a24c0a --- /dev/null +++ b/vendor/rustix/src/backend/linux_raw/termios/syscalls.rs @@ -0,0 +1,330 @@ +//! linux_raw syscalls supporting `rustix::termios`. +//! +//! # Safety +//! +//! See the `rustix::backend` module documentation for details. +#![allow(unsafe_code, clippy::undocumented_unsafe_blocks)] + +use crate::backend::c; +use crate::backend::conv::{by_ref, c_uint, ret}; +use crate::fd::BorrowedFd; +use crate::io; +use crate::pid::Pid; +#[cfg(all(feature = "alloc", feature = "procfs"))] +use crate::procfs; +use crate::termios::{ + Action, ControlModes, InputModes, LocalModes, OptionalActions, OutputModes, QueueSelector, + SpecialCodeIndex, Termios, Winsize, +}; +#[cfg(all(feature = "alloc", feature = "procfs"))] +use crate::{ffi::CStr, fs::FileType, path::DecInt}; +use core::mem::MaybeUninit; +use linux_raw_sys::general::IBSHIFT; +use linux_raw_sys::ioctl::{ + TCFLSH, TCSBRK, TCXONC, TIOCGPGRP, TIOCGSID, TIOCGWINSZ, TIOCSPGRP, TIOCSWINSZ, +}; + +#[inline] +pub(crate) fn tcgetwinsize(fd: BorrowedFd<'_>) -> io::Result<Winsize> { + unsafe { + let mut result = MaybeUninit::<Winsize>::uninit(); + ret(syscall!(__NR_ioctl, fd, c_uint(TIOCGWINSZ), &mut result))?; + Ok(result.assume_init()) + } +} + +#[inline] +pub(crate) fn tcgetattr(fd: BorrowedFd<'_>) -> io::Result<Termios> { + unsafe { + let mut result = MaybeUninit::<Termios>::uninit(); + + // QEMU's `TCGETS2` doesn't currently set `input_speed` or + // `output_speed` on PowerPC, so zero out the fields ourselves. + #[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))] + { + result.write(core::mem::zeroed()); + } + + ret(syscall!(__NR_ioctl, fd, c_uint(c::TCGETS2), &mut result))?; + + let result = result.assume_init(); + + // QEMU's `TCGETS2` doesn't currently set `input_speed` or + // `output_speed` on PowerPC, so set them manually if we can. + #[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))] + let result = { + use crate::termios::speed; + let mut result = result; + if result.output_speed == 0 && (result.control_modes.bits() & c::CBAUD) != c::BOTHER { + if let Some(output_speed) = speed::decode(result.control_modes.bits() & c::CBAUD) { + result.output_speed = output_speed; + } + } + if result.input_speed == 0 + && ((result.control_modes.bits() & c::CIBAUD) >> c::IBSHIFT) != c::BOTHER + { + // For input speeds, `B0` is special-cased to mean the input + // speed is the same as the output speed. + if ((result.control_modes.bits() & c::CIBAUD) >> c::IBSHIFT) == c::B0 { + result.input_speed = result.output_speed; + } else if let Some(input_speed) = + speed::decode((result.control_modes.bits() & c::CIBAUD) >> c::IBSHIFT) + { + result.input_speed = input_speed; + } + } + result + }; + + Ok(result) + } +} + +#[inline] +pub(crate) fn tcgetpgrp(fd: BorrowedFd<'_>) -> io::Result<Pid> { + unsafe { + let mut result = MaybeUninit::<c::pid_t>::uninit(); + ret(syscall!(__NR_ioctl, fd, c_uint(TIOCGPGRP), &mut result))?; + let pid = result.assume_init(); + + // This doesn't appear to be documented, but it appears `tcsetpgrp` can + // succceed and set the pid to 0 if we pass it a pseudo-terminal device + // fd. For now, fail with `OPNOTSUPP`. + if pid == 0 { + return Err(io::Errno::OPNOTSUPP); + } + + Ok(Pid::from_raw_unchecked(pid)) + } +} + +#[inline] +pub(crate) fn tcsetattr( + fd: BorrowedFd<'_>, + optional_actions: OptionalActions, + termios: &Termios, +) -> io::Result<()> { + // Translate from `optional_actions` into an ioctl request code. On MIPS, + // `optional_actions` already has `TCGETS` added to it. + let request = linux_raw_sys::ioctl::TCSETS2 + + if cfg!(any( + target_arch = "mips", + target_arch = "mips32r6", + target_arch = "mips64", + target_arch = "mips64r6" + )) { + optional_actions as u32 - linux_raw_sys::ioctl::TCSETS + } else { + optional_actions as u32 + }; + unsafe { + ret(syscall_readonly!( + __NR_ioctl, + fd, + c_uint(request), + by_ref(termios) + )) + } +} + +#[inline] +pub(crate) fn tcsendbreak(fd: BorrowedFd<'_>) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_ioctl, fd, c_uint(TCSBRK), c_uint(0))) } +} + +#[inline] +pub(crate) fn tcdrain(fd: BorrowedFd<'_>) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_ioctl, fd, c_uint(TCSBRK), c_uint(1))) } +} + +#[inline] +pub(crate) fn tcflush(fd: BorrowedFd<'_>, queue_selector: QueueSelector) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_ioctl, + fd, + c_uint(TCFLSH), + c_uint(queue_selector as u32) + )) + } +} + +#[inline] +pub(crate) fn tcflow(fd: BorrowedFd<'_>, action: Action) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_ioctl, + fd, + c_uint(TCXONC), + c_uint(action as u32) + )) + } +} + +#[inline] +pub(crate) fn tcgetsid(fd: BorrowedFd<'_>) -> io::Result<Pid> { + unsafe { + let mut result = MaybeUninit::<c::pid_t>::uninit(); + ret(syscall!(__NR_ioctl, fd, c_uint(TIOCGSID), &mut result))?; + let pid = result.assume_init(); + Ok(Pid::from_raw_unchecked(pid)) + } +} + +#[inline] +pub(crate) fn tcsetwinsize(fd: BorrowedFd<'_>, winsize: Winsize) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_ioctl, + fd, + c_uint(TIOCSWINSZ), + by_ref(&winsize) + )) + } +} + +#[inline] +pub(crate) fn tcsetpgrp(fd: BorrowedFd<'_>, pid: Pid) -> io::Result<()> { + let raw_pid: c::c_int = pid.as_raw_nonzero().get(); + unsafe { + ret(syscall_readonly!( + __NR_ioctl, + fd, + c_uint(TIOCSPGRP), + by_ref(&raw_pid) + )) + } +} + +/// A wrapper around a conceptual `cfsetspeed` which handles an arbitrary +/// integer speed value. +#[inline] +pub(crate) fn set_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> { + let encoded_speed = crate::termios::speed::encode(arbitrary_speed).unwrap_or(c::BOTHER); + + debug_assert_eq!(encoded_speed & !c::CBAUD, 0); + + termios.control_modes -= ControlModes::from_bits_retain(c::CBAUD | c::CIBAUD); + termios.control_modes |= + ControlModes::from_bits_retain(encoded_speed | (encoded_speed << IBSHIFT)); + + termios.input_speed = arbitrary_speed; + termios.output_speed = arbitrary_speed; + + Ok(()) +} + +/// A wrapper around a conceptual `cfsetospeed` which handles an arbitrary +/// integer speed value. +#[inline] +pub(crate) fn set_output_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> { + let encoded_speed = crate::termios::speed::encode(arbitrary_speed).unwrap_or(c::BOTHER); + + debug_assert_eq!(encoded_speed & !c::CBAUD, 0); + + termios.control_modes -= ControlModes::from_bits_retain(c::CBAUD); + termios.control_modes |= ControlModes::from_bits_retain(encoded_speed); + + termios.output_speed = arbitrary_speed; + + Ok(()) +} + +/// A wrapper around a conceptual `cfsetispeed` which handles an arbitrary +/// integer speed value. +#[inline] +pub(crate) fn set_input_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> { + let encoded_speed = crate::termios::speed::encode(arbitrary_speed).unwrap_or(c::BOTHER); + + debug_assert_eq!(encoded_speed & !c::CBAUD, 0); + + termios.control_modes -= ControlModes::from_bits_retain(c::CIBAUD); + termios.control_modes |= ControlModes::from_bits_retain(encoded_speed << IBSHIFT); + + termios.input_speed = arbitrary_speed; + + Ok(()) +} + +#[inline] +pub(crate) fn cfmakeraw(termios: &mut Termios) { + // From the Linux [`cfmakeraw` manual page]: + // + // [`cfmakeraw` manual page]: https://man7.org/linux/man-pages/man3/cfmakeraw.3.html + termios.input_modes -= InputModes::IGNBRK + | InputModes::BRKINT + | InputModes::PARMRK + | InputModes::ISTRIP + | InputModes::INLCR + | InputModes::IGNCR + | InputModes::ICRNL + | InputModes::IXON; + termios.output_modes -= OutputModes::OPOST; + termios.local_modes -= LocalModes::ECHO + | LocalModes::ECHONL + | LocalModes::ICANON + | LocalModes::ISIG + | LocalModes::IEXTEN; + termios.control_modes -= ControlModes::CSIZE | ControlModes::PARENB; + termios.control_modes |= ControlModes::CS8; + + // Musl and glibc also do these: + termios.special_codes[SpecialCodeIndex::VMIN] = 1; + termios.special_codes[SpecialCodeIndex::VTIME] = 0; +} + +#[inline] +pub(crate) fn isatty(fd: BorrowedFd<'_>) -> bool { + // On error, Linux will return either `EINVAL` (2.6.32) or `ENOTTY` + // (otherwise), because we assume we're never passing an invalid + // file descriptor (which would get `EBADF`). Either way, an error + // means we don't have a tty. + tcgetwinsize(fd).is_ok() +} + +#[cfg(all(feature = "alloc", feature = "procfs"))] +pub(crate) fn ttyname(fd: BorrowedFd<'_>, buf: &mut [MaybeUninit<u8>]) -> io::Result<usize> { + let fd_stat = crate::backend::fs::syscalls::fstat(fd)?; + + // Quick check: if `fd` isn't a character device, it's not a tty. + if FileType::from_raw_mode(fd_stat.st_mode) != FileType::CharacterDevice { + return Err(io::Errno::NOTTY); + } + + // Check that `fd` is really a tty. + tcgetwinsize(fd)?; + + // Get a fd to "/proc/self/fd". + let proc_self_fd = procfs::proc_self_fd()?; + + // Gather the ttyname by reading the "fd" file inside `proc_self_fd`. + let r = crate::backend::fs::syscalls::readlinkat( + proc_self_fd, + DecInt::from_fd(fd).as_c_str(), + buf, + )?; + + // If the number of bytes is equal to the buffer length, truncation may + // have occurred. This check also ensures that we have enough space for + // adding a NUL terminator. + if r == buf.len() { + return Err(io::Errno::RANGE); + } + + // `readlinkat` returns the number of bytes placed in the buffer. + // NUL-terminate the string at that offset. + buf[r].write(b'\0'); + + // Check that the path we read refers to the same file as `fd`. + { + // SAFETY: We just wrote the NUL byte above + let path = unsafe { CStr::from_ptr(buf.as_ptr().cast()) }; + + let path_stat = crate::backend::fs::syscalls::stat(path)?; + if path_stat.st_dev != fd_stat.st_dev || path_stat.st_ino != fd_stat.st_ino { + return Err(io::Errno::NODEV); + } + } + + Ok(r) +} |