1 files changed, 126 insertions, 0 deletions
diff --git a/vendor/rustix/src/path/dec_int.rs b/vendor/rustix/src/path/dec_int.rs
new file mode 100644
index 000000000..4006fb06c
--- /dev/null
+++ b/vendor/rustix/src/path/dec_int.rs
@@ -0,0 +1,126 @@
+//! 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::ffi::CStr;
+use crate::imp::fd::{AsFd, AsRawFd};
+#[cfg(feature = "std")]
+use core::fmt;
+use core::fmt::Write;
+use itoa::{Buffer, Integer};
+#[cfg(feature = "std")]
+use std::ffi::OsStr;
+#[cfg(feature = "std")]
+#[cfg(unix)]
+use std::os::unix::ffi::OsStrExt;
+#[cfg(feature = "std")]
+#[cfg(target_os = "wasi")]
+use std::os::wasi::ffi::OsStrExt;
+#[cfg(feature = "std")]
+use 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.
+///
+/// # Example
+///
+/// ```rust
+/// # #[cfg(feature = "path")]
+/// use rustix::path::DecInt;
+///
+/// # #[cfg(feature = "path")]
+/// 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)
+    }
+}