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-rw-r--r--vendor/rustix/src/path/dec_int.rs120
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diff --git a/vendor/rustix/src/path/dec_int.rs b/vendor/rustix/src/path/dec_int.rs
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+//! Efficient decimal integer formatting.
+//!
+//! # Safety
+//!
+//! This uses `CStr::from_bytes_with_nul_unchecked` and
+//! `str::from_utf8_unchecked`on the buffer that it filled itself.
+#![allow(unsafe_code)]
+
+use crate::backend::fd::{AsFd, AsRawFd};
+use crate::ffi::CStr;
+use core::fmt::Write;
+use itoa::{Buffer, Integer};
+#[cfg(all(feature = "std", unix))]
+use std::os::unix::ffi::OsStrExt;
+#[cfg(all(feature = "std", target_os = "wasi"))]
+use std::os::wasi::ffi::OsStrExt;
+#[cfg(feature = "std")]
+use {core::fmt, std::ffi::OsStr, std::path::Path};
+
+/// Format an integer into a decimal `Path` component, without constructing a
+/// temporary `PathBuf` or `String`.
+///
+/// This is used for opening paths such as `/proc/self/fd/<fd>` on Linux.
+///
+/// # Examples
+///
+/// ```
+/// # #[cfg(any(feature = "fs", feature = "net"))]
+/// use rustix::path::DecInt;
+///
+/// # #[cfg(any(feature = "fs", feature = "net"))]
+/// assert_eq!(
+/// format!("hello {}", DecInt::new(9876).as_ref().display()),
+/// "hello 9876"
+/// );
+/// ```
+#[derive(Clone)]
+pub struct DecInt {
+ // 20 `u8`s is enough to hold the decimal ASCII representation of any
+ // `u64`, and we add one for a NUL terminator for `as_c_str`.
+ buf: [u8; 20 + 1],
+ len: usize,
+}
+
+impl DecInt {
+ /// Construct a new path component from an integer.
+ #[inline]
+ pub fn new<Int: Integer>(i: Int) -> Self {
+ let mut me = DecIntWriter(Self {
+ buf: [0; 20 + 1],
+ len: 0,
+ });
+ let mut buf = Buffer::new();
+ me.write_str(buf.format(i)).unwrap();
+ me.0
+ }
+
+ /// Construct a new path component from a file descriptor.
+ #[inline]
+ pub fn from_fd<Fd: AsFd>(fd: Fd) -> Self {
+ Self::new(fd.as_fd().as_raw_fd())
+ }
+
+ /// Return the raw byte buffer as a `&str`.
+ #[inline]
+ pub fn as_str(&self) -> &str {
+ // SAFETY: `DecInt` always holds a formatted decimal number, so it's
+ // always valid UTF-8.
+ unsafe { core::str::from_utf8_unchecked(self.as_bytes()) }
+ }
+
+ /// Return the raw byte buffer as a `&CStr`.
+ #[inline]
+ pub fn as_c_str(&self) -> &CStr {
+ let bytes_with_nul = &self.buf[..=self.len];
+ debug_assert!(CStr::from_bytes_with_nul(bytes_with_nul).is_ok());
+
+ // SAFETY: `self.buf` holds a single decimal ASCII representation and
+ // at least one extra NUL byte.
+ unsafe { CStr::from_bytes_with_nul_unchecked(bytes_with_nul) }
+ }
+
+ /// Return the raw byte buffer.
+ #[inline]
+ pub fn as_bytes(&self) -> &[u8] {
+ &self.buf[..self.len]
+ }
+}
+
+struct DecIntWriter(DecInt);
+
+impl core::fmt::Write for DecIntWriter {
+ #[inline]
+ fn write_str(&mut self, s: &str) -> core::fmt::Result {
+ match self.0.buf.get_mut(self.0.len..self.0.len + s.len()) {
+ Some(slice) => {
+ slice.copy_from_slice(s.as_bytes());
+ self.0.len += s.len();
+ Ok(())
+ }
+ None => Err(core::fmt::Error),
+ }
+ }
+}
+
+#[cfg(feature = "std")]
+impl AsRef<Path> for DecInt {
+ #[inline]
+ fn as_ref(&self) -> &Path {
+ let as_os_str: &OsStr = OsStrExt::from_bytes(&self.buf[..self.len]);
+ Path::new(as_os_str)
+ }
+}
+
+#[cfg(feature = "std")]
+impl fmt::Debug for DecInt {
+ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+ self.as_str().fmt(fmt)
+ }
+}