1 files changed, 402 insertions, 0 deletions
diff --git a/vendor/rustix/src/imp/libc/fs/dir.rs b/vendor/rustix/src/imp/libc/fs/dir.rs
new file mode 100644
index 000000000..1e6b6066f
--- /dev/null
+++ b/vendor/rustix/src/imp/libc/fs/dir.rs
@@ -0,0 +1,402 @@
+use super::super::c;
+use super::super::conv::owned_fd;
+#[cfg(not(target_os = "illumos"))]
+use super::types::FileType;
+use crate::fd::{AsFd, BorrowedFd};
+use crate::ffi::CStr;
+#[cfg(target_os = "wasi")]
+use crate::ffi::CString;
+use crate::fs::{fcntl_getfl, fstat, openat, Mode, OFlags, Stat};
+#[cfg(not(any(
+    target_os = "illumos",
+    target_os = "netbsd",
+    target_os = "redox",
+    target_os = "wasi",
+)))] // not implemented in libc for netbsd yet
+use crate::fs::{fstatfs, StatFs};
+use crate::io;
+#[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))]
+use crate::process::fchdir;
+#[cfg(target_os = "wasi")]
+use alloc::borrow::ToOwned;
+#[cfg(not(any(
+    target_os = "android",
+    target_os = "emscripten",
+    target_os = "l4re",
+    target_os = "linux",
+    target_os = "openbsd",
+)))]
+use c::dirent as libc_dirent;
+#[cfg(not(any(
+    target_os = "android",
+    target_os = "emscripten",
+    target_os = "l4re",
+    target_os = "linux",
+)))]
+use c::readdir as libc_readdir;
+#[cfg(any(
+    target_os = "android",
+    target_os = "emscripten",
+    target_os = "l4re",
+    target_os = "linux",
+))]
+use c::{dirent64 as libc_dirent, readdir64 as libc_readdir};
+use core::fmt;
+use core::mem::zeroed;
+use core::ptr::NonNull;
+use libc_errno::{errno, set_errno, Errno};
+
+/// `DIR*`
+#[repr(transparent)]
+pub struct Dir(NonNull<c::DIR>);
+
+impl Dir {
+    /// Construct a `Dir` that reads entries from the given directory
+    /// file descriptor.
+    #[inline]
+    pub fn read_from<Fd: AsFd>(fd: Fd) -> io::Result<Self> {
+        Self::_read_from(fd.as_fd())
+    }
+
+    #[inline]
+    fn _read_from(fd: BorrowedFd<'_>) -> io::Result<Self> {
+        // Given an arbitrary `OwnedFd`, it's impossible to know whether the
+        // user holds a `dup`'d copy which could continue to modify the
+        // file description state, which would cause Undefined Behavior after
+        // our call to `fdopendir`. To prevent this, we obtain an independent
+        // `OwnedFd`.
+        let flags = fcntl_getfl(&fd)?;
+        let fd_for_dir = openat(&fd, cstr!("."), flags | OFlags::CLOEXEC, Mode::empty())?;
+
+        let raw = owned_fd(fd_for_dir);
+        unsafe {
+            let libc_dir = c::fdopendir(raw);
+
+            if let Some(libc_dir) = NonNull::new(libc_dir) {
+                Ok(Self(libc_dir))
+            } else {
+                let e = io::Errno::last_os_error();
+                let _ = c::close(raw);
+                Err(e)
+            }
+        }
+    }
+
+    /// `rewinddir(self)`
+    #[inline]
+    pub fn rewind(&mut self) {
+        unsafe { c::rewinddir(self.0.as_ptr()) }
+    }
+
+    /// `readdir(self)`, where `None` means the end of the directory.
+    pub fn read(&mut self) -> Option<io::Result<DirEntry>> {
+        set_errno(Errno(0));
+        let dirent_ptr = unsafe { libc_readdir(self.0.as_ptr()) };
+        if dirent_ptr.is_null() {
+            let curr_errno = errno().0;
+            if curr_errno == 0 {
+                // We successfully reached the end of the stream.
+                None
+            } else {
+                // `errno` is unknown or non-zero, so an error occurred.
+                Some(Err(io::Errno(curr_errno)))
+            }
+        } else {
+            // We successfully read an entry.
+            unsafe {
+                // We have our own copy of OpenBSD's dirent; check that the
+                // layout minimally matches libc's.
+                #[cfg(target_os = "openbsd")]
+                check_dirent_layout(&*dirent_ptr);
+
+                let result = DirEntry {
+                    dirent: read_dirent(&*dirent_ptr.cast()),
+
+                    #[cfg(target_os = "wasi")]
+                    name: CStr::from_ptr((*dirent_ptr).d_name.as_ptr()).to_owned(),
+                };
+
+                Some(Ok(result))
+            }
+        }
+    }
+
+    /// `fstat(self)`
+    #[inline]
+    pub fn stat(&self) -> io::Result<Stat> {
+        fstat(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.0.as_ptr())) })
+    }
+
+    /// `fstatfs(self)`
+    #[cfg(not(any(
+        target_os = "illumos",
+        target_os = "netbsd",
+        target_os = "redox",
+        target_os = "wasi",
+    )))] // not implemented in libc for netbsd yet
+    #[inline]
+    pub fn statfs(&self) -> io::Result<StatFs> {
+        fstatfs(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.0.as_ptr())) })
+    }
+
+    /// `fchdir(self)`
+    #[cfg(not(any(target_os = "fuchsia", target_os = "wasi")))]
+    #[inline]
+    pub fn chdir(&self) -> io::Result<()> {
+        fchdir(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.0.as_ptr())) })
+    }
+}
+
+// A `dirent` pointer returned from `readdir` may not point to a full `dirent`
+// struct, as the name is NUL-terminated and memory may not be allocated for
+// the full extent of the struct. Copy the fields one at a time.
+unsafe fn read_dirent(input: &libc_dirent) -> libc_dirent {
+    #[cfg(not(target_os = "illumos"))]
+    let d_type = input.d_type;
+
+    #[cfg(not(any(
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "ios",
+        target_os = "macos",
+        target_os = "netbsd",
+        target_os = "wasi",
+    )))]
+    let d_off = input.d_off;
+
+    #[cfg(not(any(
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_os = "openbsd",
+    )))]
+    let d_ino = input.d_ino;
+
+    #[cfg(any(target_os = "freebsd", target_os = "netbsd", target_os = "openbsd"))]
+    let d_fileno = input.d_fileno;
+
+    #[cfg(not(target_os = "wasi"))]
+    let d_reclen = input.d_reclen;
+
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_os = "openbsd",
+        target_os = "ios",
+        target_os = "macos",
+    ))]
+    let d_namlen = input.d_namlen;
+
+    #[cfg(any(target_os = "ios", target_os = "macos"))]
+    let d_seekoff = input.d_seekoff;
+
+    // Construct the input. Rust will give us an error if any OS has a input
+    // with a field that we missed here. And we can avoid blindly copying the
+    // whole `d_name` field, which may not be entirely allocated.
+    #[cfg_attr(target_os = "wasi", allow(unused_mut))]
+    let mut dirent = libc_dirent {
+        #[cfg(not(target_os = "illumos"))]
+        d_type,
+        #[cfg(not(any(
+            target_os = "dragonfly",
+            target_os = "freebsd",
+            target_os = "ios",
+            target_os = "macos",
+            target_os = "netbsd",
+            target_os = "wasi",
+        )))]
+        d_off,
+        #[cfg(not(any(
+            target_os = "dragonfly",
+            target_os = "freebsd",
+            target_os = "netbsd",
+            target_os = "openbsd",
+        )))]
+        d_ino,
+        #[cfg(any(target_os = "freebsd", target_os = "netbsd", target_os = "openbsd"))]
+        d_fileno,
+        #[cfg(not(target_os = "wasi"))]
+        d_reclen,
+        #[cfg(any(
+            target_os = "freebsd",
+            target_os = "ios",
+            target_os = "macos",
+            target_os = "netbsd",
+            target_os = "openbsd",
+        ))]
+        d_namlen,
+        #[cfg(any(target_os = "ios", target_os = "macos"))]
+        d_seekoff,
+        // The `d_name` field is NUL-terminated, and we need to be careful not
+        // to read bytes past the NUL, even though they're within the nominal
+        // extent of the `struct dirent`, because they may not be allocated. So
+        // don't read it from `dirent_ptr`.
+        //
+        // In theory this could use `MaybeUninit::uninit().assume_init()`, but
+        // that [invokes undefined behavior].
+        //
+        // [invokes undefined behavior]: https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#initialization-invariant
+        d_name: zeroed(),
+        #[cfg(target_os = "openbsd")]
+        __d_padding: zeroed(),
+    };
+
+    // Copy from d_name, reading up to and including the first NUL.
+    #[cfg(not(target_os = "wasi"))]
+    {
+        let name_len = CStr::from_ptr(input.d_name.as_ptr())
+            .to_bytes_with_nul()
+            .len();
+        dirent.d_name[..name_len].copy_from_slice(&input.d_name[..name_len]);
+    }
+
+    dirent
+}
+
+/// `Dir` implements `Send` but not `Sync`, because we use `readdir` which is
+/// not guaranteed to be thread-safe. Users can wrap this in a `Mutex` if they
+/// need `Sync`, which is effectively what'd need to do to implement `Sync`
+/// ourselves.
+unsafe impl Send for Dir {}
+
+impl Drop for Dir {
+    #[inline]
+    fn drop(&mut self) {
+        unsafe { c::closedir(self.0.as_ptr()) };
+    }
+}
+
+impl Iterator for Dir {
+    type Item = io::Result<DirEntry>;
+
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        Self::read(self)
+    }
+}
+
+impl fmt::Debug for Dir {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Dir")
+            .field("fd", unsafe { &c::dirfd(self.0.as_ptr()) })
+            .finish()
+    }
+}
+
+/// `struct dirent`
+#[derive(Debug)]
+pub struct DirEntry {
+    dirent: libc_dirent,
+
+    #[cfg(target_os = "wasi")]
+    name: CString,
+}
+
+impl DirEntry {
+    /// Returns the file name of this directory entry.
+    #[inline]
+    pub fn file_name(&self) -> &CStr {
+        #[cfg(not(target_os = "wasi"))]
+        unsafe {
+            CStr::from_ptr(self.dirent.d_name.as_ptr())
+        }
+
+        #[cfg(target_os = "wasi")]
+        &self.name
+    }
+
+    /// Returns the type of this directory entry.
+    #[cfg(not(target_os = "illumos"))]
+    #[inline]
+    pub fn file_type(&self) -> FileType {
+        FileType::from_dirent_d_type(self.dirent.d_type)
+    }
+
+    /// Return the inode number of this directory entry.
+    #[cfg(not(any(
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_os = "openbsd",
+    )))]
+    #[inline]
+    pub fn ino(&self) -> u64 {
+        self.dirent.d_ino
+    }
+
+    /// Return the inode number of this directory entry.
+    #[cfg(any(
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_os = "openbsd",
+    ))]
+    #[inline]
+    pub fn ino(&self) -> u64 {
+        #[allow(clippy::useless_conversion)]
+        self.dirent.d_fileno.into()
+    }
+}
+
+/// libc's OpenBSD `dirent` has a private field so we can't construct it
+/// directly, so we declare it ourselves to make all fields accessible.
+#[cfg(target_os = "openbsd")]
+#[repr(C)]
+#[derive(Debug)]
+struct libc_dirent {
+    d_fileno: c::ino_t,
+    d_off: c::off_t,
+    d_reclen: u16,
+    d_type: u8,
+    d_namlen: u8,
+    __d_padding: [u8; 4],
+    d_name: [c::c_char; 256],
+}
+
+/// We have our own copy of OpenBSD's dirent; check that the layout
+/// minimally matches libc's.
+#[cfg(target_os = "openbsd")]
+fn check_dirent_layout(dirent: &c::dirent) {
+    use crate::utils::as_ptr;
+    use core::mem::{align_of, size_of};
+
+    // Check that the basic layouts match.
+    assert_eq!(size_of::<libc_dirent>(), size_of::<c::dirent>());
+    assert_eq!(align_of::<libc_dirent>(), align_of::<c::dirent>());
+
+    // Check that the field offsets match.
+    assert_eq!(
+        {
+            let z = libc_dirent {
+                d_fileno: 0_u64,
+                d_off: 0_i64,
+                d_reclen: 0_u16,
+                d_type: 0_u8,
+                d_namlen: 0_u8,
+                __d_padding: [0_u8; 4],
+                d_name: [0 as c::c_char; 256],
+            };
+            let base = as_ptr(&z) as usize;
+            (
+                (as_ptr(&z.d_fileno) as usize) - base,
+                (as_ptr(&z.d_off) as usize) - base,
+                (as_ptr(&z.d_reclen) as usize) - base,
+                (as_ptr(&z.d_type) as usize) - base,
+                (as_ptr(&z.d_namlen) as usize) - base,
+                (as_ptr(&z.d_name) as usize) - base,
+            )
+        },
+        {
+            let z = dirent;
+            let base = as_ptr(z) as usize;
+            (
+                (as_ptr(&z.d_fileno) as usize) - base,
+                (as_ptr(&z.d_off) as usize) - base,
+                (as_ptr(&z.d_reclen) as usize) - base,
+                (as_ptr(&z.d_type) as usize) - base,
+                (as_ptr(&z.d_namlen) as usize) - base,
+                (as_ptr(&z.d_name) as usize) - base,
+            )
+        }
+    );
+}