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authormo khan <mo@mokhan.ca>2025-07-02 18:36:06 -0600
committermo khan <mo@mokhan.ca>2025-07-02 18:36:06 -0600
commit8cdfa445d6629ffef4cb84967ff7017654045bc2 (patch)
tree22f0b0907c024c78d26a731e2e1f5219407d8102 /vendor/rustix/src/backend/libc/termios/syscalls.rs
parent4351c74c7c5f97156bc94d3a8549b9940ac80e3f (diff)
chore: add vendor directory
Diffstat (limited to 'vendor/rustix/src/backend/libc/termios/syscalls.rs')
-rw-r--r--vendor/rustix/src/backend/libc/termios/syscalls.rs518
1 files changed, 518 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/libc/termios/syscalls.rs b/vendor/rustix/src/backend/libc/termios/syscalls.rs
new file mode 100644
index 00000000..e27f0b2e
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+++ b/vendor/rustix/src/backend/libc/termios/syscalls.rs
@@ -0,0 +1,518 @@
+//! libc syscalls supporting `rustix::termios`.
+//!
+//! # Safety
+//!
+//! See the `rustix::backend::syscalls` module documentation for details.
+
+use crate::backend::c;
+#[cfg(not(target_os = "wasi"))]
+use crate::backend::conv::ret_pid_t;
+use crate::backend::conv::{borrowed_fd, ret};
+use crate::fd::BorrowedFd;
+#[cfg(feature = "alloc")]
+#[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))]
+use crate::ffi::CStr;
+#[cfg(any(
+ not(target_os = "espidf"),
+ not(any(target_os = "fuchsia", target_os = "wasi"))
+))]
+use core::mem::MaybeUninit;
+#[cfg(not(target_os = "wasi"))]
+use {crate::io, crate::pid::Pid};
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+use {
+ crate::termios::{Action, OptionalActions, QueueSelector, Termios, Winsize},
+ crate::utils::as_mut_ptr,
+};
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+pub(crate) fn tcgetattr(fd: BorrowedFd<'_>) -> io::Result<Termios> {
+ // On Linux, use `TCGETS2`, and fall back to `TCGETS` if needed.
+ #[cfg(linux_kernel)]
+ {
+ use crate::termios::{ControlModes, InputModes, LocalModes, OutputModes, SpecialCodes};
+
+ let mut termios2 = MaybeUninit::<c::termios2>::uninit();
+ let ptr = termios2.as_mut_ptr();
+
+ // SAFETY: This invokes the `TCGETS2` ioctl, which initializes the full
+ // `Termios` structure.
+ let termios2 = unsafe {
+ match ret(c::ioctl(borrowed_fd(fd), c::TCGETS2 as _, ptr)) {
+ Ok(()) => {}
+
+ // A `NOTTY` or `ACCESS` might mean the OS doesn't support
+ // `TCGETS2`, for example a seccomp environment or WSL that
+ // only knows about `TCGETS`. Fall back to the old `TCGETS`.
+ #[cfg(not(any(target_arch = "powerpc", target_arch = "powerpc64")))]
+ Err(io::Errno::NOTTY) | Err(io::Errno::ACCESS) => {
+ tcgetattr_fallback(fd, &mut termios2)?
+ }
+
+ Err(err) => return Err(err),
+ }
+
+ // Now all the fields are set.
+ termios2.assume_init()
+ };
+
+ // Convert from the Linux `termios2` to our `Termios`.
+ let mut result = Termios {
+ input_modes: InputModes::from_bits_retain(termios2.c_iflag),
+ output_modes: OutputModes::from_bits_retain(termios2.c_oflag),
+ control_modes: ControlModes::from_bits_retain(termios2.c_cflag),
+ local_modes: LocalModes::from_bits_retain(termios2.c_lflag),
+ line_discipline: termios2.c_line,
+ special_codes: SpecialCodes(Default::default()),
+
+ // On PowerPC musl targets, `c_ispeed`/`c_ospeed` are named
+ // `__c_ispeed`/`__c_ospeed`.
+ #[cfg(not(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ )))]
+ input_speed: termios2.c_ispeed,
+ #[cfg(not(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ )))]
+ output_speed: termios2.c_ospeed,
+ #[cfg(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ ))]
+ input_speed: termios2.__c_ispeed,
+ #[cfg(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ ))]
+ output_speed: termios2.__c_ospeed,
+ };
+
+ // Copy in the control codes, since libc's `c_cc` array may have a
+ // different length from the ioctl's.
+ let nccs = termios2.c_cc.len();
+ result.special_codes.0[..nccs].copy_from_slice(&termios2.c_cc);
+
+ Ok(result)
+ }
+
+ #[cfg(not(linux_kernel))]
+ unsafe {
+ let mut result = MaybeUninit::<Termios>::uninit();
+
+ // `result` is a `Termios` which starts with the same layout as
+ // `c::termios`, so we can cast the pointer.
+ ret(c::tcgetattr(borrowed_fd(fd), result.as_mut_ptr().cast()))?;
+
+ Ok(result.assume_init())
+ }
+}
+
+/// Implement `tcgetattr` using the old `TCGETS` ioctl.
+#[cfg(all(
+ linux_kernel,
+ not(any(target_arch = "powerpc", target_arch = "powerpc64"))
+))]
+#[cold]
+fn tcgetattr_fallback(
+ fd: BorrowedFd<'_>,
+ termios: &mut MaybeUninit<c::termios2>,
+) -> io::Result<()> {
+ use crate::termios::speed;
+ use core::ptr::{addr_of, addr_of_mut};
+
+ // SAFETY: This invokes the `TCGETS` ioctl, which, if it succeeds,
+ // initializes the `Termios` structure except for the `input_speed` and
+ // `output_speed` fields, which we manually initialize before forming a
+ // reference to the full `Termios`.
+ unsafe {
+ let ptr = termios.as_mut_ptr();
+
+ // Do the old `TCGETS` call, which doesn't initialize `input_speed` or
+ // `output_speed`.
+ ret(c::ioctl(borrowed_fd(fd), c::TCGETS as _, ptr))?;
+
+ // Read the `control_modes` field without forming a reference to the
+ // `Termios` because it isn't fully initialized yet.
+ let control_modes = addr_of!((*ptr).c_cflag).read();
+
+ // Infer `output_speed`.
+ let encoded_out = control_modes & c::CBAUD;
+ let output_speed = match speed::decode(encoded_out) {
+ Some(output_speed) => output_speed,
+ None => return Err(io::Errno::RANGE),
+ };
+ addr_of_mut!((*ptr).c_ospeed).write(output_speed);
+
+ // Infer `input_speed`. For input speeds, `B0` is special-cased to mean
+ // the input speed is the same as the output speed.
+ let encoded_in = (control_modes & c::CIBAUD) >> c::IBSHIFT;
+ let input_speed = if encoded_in == c::B0 {
+ output_speed
+ } else {
+ match speed::decode(encoded_in) {
+ Some(input_speed) => input_speed,
+ None => return Err(io::Errno::RANGE),
+ }
+ };
+ addr_of_mut!((*ptr).c_ispeed).write(input_speed);
+ }
+
+ Ok(())
+}
+
+#[cfg(not(target_os = "wasi"))]
+pub(crate) fn tcgetpgrp(fd: BorrowedFd<'_>) -> io::Result<Pid> {
+ unsafe {
+ let pid = ret_pid_t(c::tcgetpgrp(borrowed_fd(fd)))?;
+
+ // This doesn't appear to be documented, but on Linux, it appears
+ // `tcsetpgrp` can succeed and set the pid to 0 if we pass it a
+ // pseudo-terminal device fd. For now, translate it into `OPNOTSUPP`.
+ #[cfg(linux_kernel)]
+ if pid == 0 {
+ return Err(io::Errno::OPNOTSUPP);
+ }
+
+ Ok(Pid::from_raw_unchecked(pid))
+ }
+}
+
+#[cfg(not(target_os = "wasi"))]
+pub(crate) fn tcsetpgrp(fd: BorrowedFd<'_>, pid: Pid) -> io::Result<()> {
+ unsafe { ret(c::tcsetpgrp(borrowed_fd(fd), pid.as_raw_nonzero().get())) }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+pub(crate) fn tcsetattr(
+ fd: BorrowedFd<'_>,
+ optional_actions: OptionalActions,
+ termios: &Termios,
+) -> io::Result<()> {
+ // On Linux, use `TCSETS2`, and fall back to `TCSETS` if needed.
+ #[cfg(linux_kernel)]
+ {
+ use crate::termios::speed;
+
+ let output_speed = termios.output_speed();
+ let input_speed = termios.input_speed();
+
+ let mut termios2 = c::termios2 {
+ c_iflag: termios.input_modes.bits(),
+ c_oflag: termios.output_modes.bits(),
+ c_cflag: termios.control_modes.bits(),
+ c_lflag: termios.local_modes.bits(),
+ c_line: termios.line_discipline,
+ c_cc: Default::default(),
+
+ // On PowerPC musl targets, `c_ispeed`/`c_ospeed` are named
+ // `__c_ispeed`/`__c_ospeed`.
+ #[cfg(not(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ )))]
+ c_ispeed: input_speed,
+ #[cfg(not(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ )))]
+ c_ospeed: output_speed,
+ #[cfg(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ ))]
+ __c_ispeed: input_speed,
+ #[cfg(all(
+ target_env = "musl",
+ any(target_arch = "powerpc", target_arch = "powerpc64")
+ ))]
+ __c_ospeed: output_speed,
+ };
+
+ // Ensure that our input and output speeds are set, as `libc`
+ // routines don't always support setting these separately.
+ termios2.c_cflag &= !c::CBAUD;
+ termios2.c_cflag |= speed::encode(output_speed).unwrap_or(c::BOTHER);
+ termios2.c_cflag &= !c::CIBAUD;
+ termios2.c_cflag |= speed::encode(input_speed).unwrap_or(c::BOTHER) << c::IBSHIFT;
+
+ // Copy in the control codes, since libc's `c_cc` array may have a
+ // different length from the ioctl's.
+ let nccs = termios2.c_cc.len();
+ termios2
+ .c_cc
+ .copy_from_slice(&termios.special_codes.0[..nccs]);
+
+ // Translate from `optional_actions` into a `TCSETS2` ioctl request
+ // code. On MIPS, `optional_actions` has `TCSETS` added to it.
+ let request = c::TCSETS2 as c::c_ulong
+ + if cfg!(any(
+ target_arch = "mips",
+ target_arch = "mips32r6",
+ target_arch = "mips64",
+ target_arch = "mips64r6"
+ )) {
+ optional_actions as c::c_ulong - c::TCSETS as c::c_ulong
+ } else {
+ optional_actions as c::c_ulong
+ };
+
+ // SAFETY: This invokes the `TCSETS2` ioctl.
+ unsafe {
+ match ret(c::ioctl(borrowed_fd(fd), request as _, &termios2)) {
+ Ok(()) => Ok(()),
+
+ // Similar to `tcgetattr_fallback`, `NOTTY` or `ACCESS` might
+ // mean the OS doesn't support `TCSETS2`. Fall back to the old
+ // `TCSETS`.
+ #[cfg(not(any(target_arch = "powerpc", target_arch = "powerpc64")))]
+ Err(io::Errno::NOTTY) | Err(io::Errno::ACCESS) => {
+ tcsetattr_fallback(fd, optional_actions, &termios2)
+ }
+
+ Err(err) => Err(err),
+ }
+ }
+ }
+
+ #[cfg(not(linux_kernel))]
+ unsafe {
+ ret(c::tcsetattr(
+ borrowed_fd(fd),
+ optional_actions as _,
+ crate::utils::as_ptr(termios).cast(),
+ ))
+ }
+}
+
+/// Implement `tcsetattr` using the old `TCSETS` ioctl.
+#[cfg(all(
+ linux_kernel,
+ not(any(target_arch = "powerpc", target_arch = "powerpc64"))
+))]
+#[cold]
+fn tcsetattr_fallback(
+ fd: BorrowedFd<'_>,
+ optional_actions: OptionalActions,
+ termios2: &c::termios2,
+) -> io::Result<()> {
+ // `TCSETS` silently accepts `BOTHER` in `c_cflag` even though it doesn't
+ // read `c_ispeed`/`c_ospeed`, so detect this case and fail if needed.
+ let encoded_out = termios2.c_cflag & c::CBAUD;
+ let encoded_in = (termios2.c_cflag & c::CIBAUD) >> c::IBSHIFT;
+ if encoded_out == c::BOTHER || encoded_in == c::BOTHER {
+ return Err(io::Errno::RANGE);
+ }
+
+ // Translate from `optional_actions` into a `TCSETS` ioctl request code. On
+ // MIPS, `optional_actions` already has `TCSETS` added to it.
+ let request = if cfg!(any(
+ target_arch = "mips",
+ target_arch = "mips32r6",
+ target_arch = "mips64",
+ target_arch = "mips64r6"
+ )) {
+ optional_actions as c::c_ulong
+ } else {
+ optional_actions as c::c_ulong + c::TCSETS as c::c_ulong
+ };
+
+ // SAFETY: This invokes the `TCSETS` ioctl.
+ unsafe { ret(c::ioctl(borrowed_fd(fd), request as _, termios2)) }
+}
+
+#[cfg(not(target_os = "wasi"))]
+pub(crate) fn tcsendbreak(fd: BorrowedFd<'_>) -> io::Result<()> {
+ unsafe { ret(c::tcsendbreak(borrowed_fd(fd), 0)) }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+pub(crate) fn tcdrain(fd: BorrowedFd<'_>) -> io::Result<()> {
+ unsafe { ret(c::tcdrain(borrowed_fd(fd))) }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+pub(crate) fn tcflush(fd: BorrowedFd<'_>, queue_selector: QueueSelector) -> io::Result<()> {
+ unsafe { ret(c::tcflush(borrowed_fd(fd), queue_selector as _)) }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+pub(crate) fn tcflow(fd: BorrowedFd<'_>, action: Action) -> io::Result<()> {
+ unsafe { ret(c::tcflow(borrowed_fd(fd), action as _)) }
+}
+
+#[cfg(not(target_os = "wasi"))]
+pub(crate) fn tcgetsid(fd: BorrowedFd<'_>) -> io::Result<Pid> {
+ unsafe {
+ let pid = ret_pid_t(c::tcgetsid(borrowed_fd(fd)))?;
+ Ok(Pid::from_raw_unchecked(pid))
+ }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "horizon", target_os = "wasi")))]
+pub(crate) fn tcsetwinsize(fd: BorrowedFd<'_>, winsize: Winsize) -> io::Result<()> {
+ unsafe { ret(c::ioctl(borrowed_fd(fd), c::TIOCSWINSZ, &winsize)) }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "horizon", target_os = "wasi")))]
+pub(crate) fn tcgetwinsize(fd: BorrowedFd<'_>) -> io::Result<Winsize> {
+ unsafe {
+ let mut buf = MaybeUninit::<Winsize>::uninit();
+ ret(c::ioctl(
+ borrowed_fd(fd),
+ c::TIOCGWINSZ.into(),
+ buf.as_mut_ptr(),
+ ))?;
+ Ok(buf.assume_init())
+ }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "nto", target_os = "wasi")))]
+#[inline]
+pub(crate) fn set_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> {
+ #[cfg(bsd)]
+ let encoded_speed = arbitrary_speed;
+
+ #[cfg(not(bsd))]
+ let encoded_speed = match crate::termios::speed::encode(arbitrary_speed) {
+ Some(encoded_speed) => encoded_speed,
+ #[cfg(linux_kernel)]
+ None => c::BOTHER,
+ #[cfg(not(linux_kernel))]
+ None => return Err(io::Errno::INVAL),
+ };
+
+ #[cfg(not(linux_kernel))]
+ unsafe {
+ ret(c::cfsetspeed(
+ as_mut_ptr(termios).cast(),
+ encoded_speed.into(),
+ ))
+ }
+
+ // Linux libc implementations don't support arbitrary speeds, so we encode
+ // the speed manually.
+ #[cfg(linux_kernel)]
+ {
+ use crate::termios::ControlModes;
+
+ 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 << c::IBSHIFT));
+
+ termios.input_speed = arbitrary_speed;
+ termios.output_speed = arbitrary_speed;
+
+ Ok(())
+ }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+#[inline]
+pub(crate) fn set_output_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> {
+ #[cfg(bsd)]
+ let encoded_speed = arbitrary_speed;
+
+ #[cfg(not(bsd))]
+ let encoded_speed = match crate::termios::speed::encode(arbitrary_speed) {
+ Some(encoded_speed) => encoded_speed,
+ #[cfg(linux_kernel)]
+ None => c::BOTHER,
+ #[cfg(not(linux_kernel))]
+ None => return Err(io::Errno::INVAL),
+ };
+
+ #[cfg(not(linux_kernel))]
+ unsafe {
+ ret(c::cfsetospeed(
+ as_mut_ptr(termios).cast(),
+ encoded_speed.into(),
+ ))
+ }
+
+ // Linux libc implementations don't support arbitrary speeds or setting the
+ // input and output speeds separately, so we encode the speed manually.
+ #[cfg(linux_kernel)]
+ {
+ use crate::termios::ControlModes;
+
+ 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(())
+ }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "wasi")))]
+#[inline]
+pub(crate) fn set_input_speed(termios: &mut Termios, arbitrary_speed: u32) -> io::Result<()> {
+ #[cfg(bsd)]
+ let encoded_speed = arbitrary_speed;
+
+ #[cfg(not(bsd))]
+ let encoded_speed = match crate::termios::speed::encode(arbitrary_speed) {
+ Some(encoded_speed) => encoded_speed,
+ #[cfg(linux_kernel)]
+ None => c::BOTHER,
+ #[cfg(not(linux_kernel))]
+ None => return Err(io::Errno::INVAL),
+ };
+
+ #[cfg(not(linux_kernel))]
+ unsafe {
+ ret(c::cfsetispeed(
+ as_mut_ptr(termios).cast(),
+ encoded_speed.into(),
+ ))
+ }
+
+ // Linux libc implementations don't support arbitrary speeds or setting the
+ // input and output speeds separately, so we encode the speed manually.
+ #[cfg(linux_kernel)]
+ {
+ use crate::termios::ControlModes;
+
+ 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 << c::IBSHIFT);
+
+ termios.input_speed = arbitrary_speed;
+
+ Ok(())
+ }
+}
+
+#[cfg(not(any(target_os = "espidf", target_os = "nto", target_os = "wasi")))]
+#[inline]
+pub(crate) fn cfmakeraw(termios: &mut Termios) {
+ unsafe { c::cfmakeraw(as_mut_ptr(termios).cast()) }
+}
+
+pub(crate) fn isatty(fd: BorrowedFd<'_>) -> bool {
+ // Use the return value of `isatty` alone. We don't check `errno` because
+ // we return `bool` rather than `io::Result<bool>`, because we assume
+ // `BorrowedFd` protects us from `EBADF`, and any other reasonably
+ // anticipated `errno` value would end up interpreted as “assume it's not a
+ // terminal” anyway.
+ unsafe { c::isatty(borrowed_fd(fd)) != 0 }
+}
+
+#[cfg(feature = "alloc")]
+#[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))]
+pub(crate) fn ttyname(dirfd: BorrowedFd<'_>, buf: &mut [MaybeUninit<u8>]) -> io::Result<usize> {
+ unsafe {
+ // `ttyname_r` returns its error status rather than using `errno`.
+ match c::ttyname_r(borrowed_fd(dirfd), buf.as_mut_ptr().cast(), buf.len()) {
+ 0 => Ok(CStr::from_ptr(buf.as_ptr().cast()).to_bytes().len()),
+ err => Err(io::Errno::from_raw_os_error(err)),
+ }
+ }
+}