1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/libc/pty/syscalls.rs b/vendor/rustix/src/backend/libc/pty/syscalls.rs
new file mode 100644
index 000000000..178201ead
--- /dev/null
+++ b/vendor/rustix/src/backend/libc/pty/syscalls.rs
@@ -0,0 +1,86 @@
+//! libc syscalls supporting `rustix::pty`.
+
+use crate::backend::c;
+use crate::backend::conv::{borrowed_fd, ret};
+use crate::fd::BorrowedFd;
+use crate::io;
+#[cfg(not(target_os = "android"))]
+use {crate::backend::conv::ret_owned_fd, crate::fd::OwnedFd, crate::pty::OpenptFlags};
+#[cfg(any(apple, linux_like, target_os = "freebsd", target_os = "fuchsia"))]
+use {
+    crate::ffi::{CStr, CString},
+    crate::path::SMALL_PATH_BUFFER_SIZE,
+    alloc::borrow::ToOwned,
+    alloc::vec::Vec,
+};
+
+#[cfg(not(linux_kernel))]
+#[inline]
+pub(crate) fn openpt(flags: OpenptFlags) -> io::Result<OwnedFd> {
+    unsafe { ret_owned_fd(c::posix_openpt(flags.bits() as _)) }
+}
+
+#[cfg(any(apple, linux_like, target_os = "freebsd", target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn ptsname(fd: 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 {
+        // On platforms with `ptsname_r`, use it.
+        #[cfg(any(target_os = "freebsd", linux_like, target_os = "fuchsia"))]
+        let r = unsafe { c::ptsname_r(borrowed_fd(fd), buffer.as_mut_ptr().cast(), buffer.len()) };
+
+        // MacOS 10.13.4 has `ptsname_r`; use it if we have it, otherwise fall
+        // back to calling the underlying ioctl directly.
+        #[cfg(apple)]
+        let r = unsafe {
+            weak! { fn ptsname_r(c::c_int, *mut c::c_char, c::size_t) -> c::c_int }
+
+            if let Some(libc_ptsname_r) = ptsname_r.get() {
+                libc_ptsname_r(borrowed_fd(fd), buffer.as_mut_ptr().cast(), buffer.len())
+            } else {
+                // The size declared in the `TIOCPTYGNAME` macro in sys/ttycom.h is 128.
+                let mut name: [u8; 128] = [0_u8; 128];
+                match c::ioctl(borrowed_fd(fd), c::TIOCPTYGNAME as u64, &mut name) {
+                    0 => {
+                        let len = CStr::from_ptr(name.as_ptr().cast()).to_bytes().len();
+                        std::ptr::copy_nonoverlapping(name.as_ptr(), buffer.as_mut_ptr(), len + 1);
+                        0
+                    }
+                    _ => libc_errno::errno().0,
+                }
+            }
+        };
+
+        if r == 0 {
+            return Ok(unsafe { CStr::from_ptr(buffer.as_ptr().cast()).to_owned() });
+        }
+        if r != c::ERANGE {
+            return Err(io::Errno::from_raw_os_error(r));
+        }
+
+        buffer.reserve(1); // use `Vec` reallocation strategy to grow capacity exponentially
+        buffer.resize(buffer.capacity(), 0_u8);
+    }
+}
+
+#[inline]
+pub(crate) fn unlockpt(fd: BorrowedFd) -> io::Result<()> {
+    unsafe { ret(c::unlockpt(borrowed_fd(fd))) }
+}
+
+#[cfg(not(linux_kernel))]
+#[inline]
+pub(crate) fn grantpt(fd: BorrowedFd) -> io::Result<()> {
+    unsafe { ret(c::grantpt(borrowed_fd(fd))) }
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn ioctl_tiocgptpeer(fd: BorrowedFd, flags: OpenptFlags) -> io::Result<OwnedFd> {
+    unsafe { ret_owned_fd(c::ioctl(borrowed_fd(fd), c::TIOCGPTPEER, flags.bits())) }
+}