| //! Functions which operate on file descriptors which might be terminals. |
| |
| use crate::backend; |
| #[cfg(any( |
| all(linux_raw, feature = "procfs"), |
| all(libc, not(any(target_os = "fuchsia", target_os = "wasi"))), |
| ))] |
| use crate::io; |
| use backend::fd::AsFd; |
| #[cfg(any( |
| all(linux_raw, feature = "procfs"), |
| all(libc, not(any(target_os = "fuchsia", target_os = "wasi"))), |
| ))] |
| use { |
| crate::ffi::CString, crate::path::SMALL_PATH_BUFFER_SIZE, alloc::vec::Vec, |
| backend::fd::BorrowedFd, |
| }; |
| |
| /// `isatty(fd)`—Tests whether a file descriptor refers to a terminal. |
| /// |
| /// # References |
| /// - [POSIX] |
| /// - [Linux] |
| /// |
| /// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/isatty.html |
| /// [Linux]: https://man7.org/linux/man-pages/man3/isatty.3.html |
| #[inline] |
| pub fn isatty<Fd: AsFd>(fd: Fd) -> bool { |
| backend::termios::syscalls::isatty(fd.as_fd()) |
| } |
| |
| /// `ttyname_r(fd)` |
| /// |
| /// If `reuse` is non-empty, reuse its buffer to store the result if possible. |
| /// |
| /// # References |
| /// - [POSIX] |
| /// - [Linux] |
| /// |
| /// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/ttyname.html |
| /// [Linux]: https://man7.org/linux/man-pages/man3/ttyname.3.html |
| #[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))] |
| #[cfg(feature = "procfs")] |
| #[cfg_attr(doc_cfg, doc(cfg(feature = "procfs")))] |
| #[inline] |
| pub fn ttyname<Fd: AsFd, B: Into<Vec<u8>>>(dirfd: Fd, reuse: B) -> io::Result<CString> { |
| _ttyname(dirfd.as_fd(), reuse.into()) |
| } |
| |
| #[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))] |
| #[cfg(feature = "procfs")] |
| fn _ttyname(dirfd: BorrowedFd<'_>, mut buffer: Vec<u8>) -> io::Result<CString> { |
| // This code would benefit from having a better way to read into |
| // uninitialized memory, but that requires `unsafe`. |
| buffer.clear(); |
| buffer.reserve(SMALL_PATH_BUFFER_SIZE); |
| buffer.resize(buffer.capacity(), 0_u8); |
| |
| loop { |
| match backend::termios::syscalls::ttyname(dirfd, &mut buffer) { |
| Err(io::Errno::RANGE) => { |
| buffer.reserve(1); // use `Vec` reallocation strategy to grow capacity exponentially |
| buffer.resize(buffer.capacity(), 0_u8); |
| } |
| Ok(len) => { |
| buffer.resize(len, 0_u8); |
| return Ok(CString::new(buffer).unwrap()); |
| } |
| Err(errno) => return Err(errno), |
| } |
| } |
| } |