1 files changed, 423 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/libc/fs/dir.rs b/vendor/rustix/src/backend/libc/fs/dir.rs
new file mode 100644
index 0000000..82a0a90
--- /dev/null
+++ b/vendor/rustix/src/backend/libc/fs/dir.rs
@@ -0,0 +1,423 @@
+#[cfg(not(any(solarish, target_os = "haiku", target_os = "nto", target_os = "vita")))]
+use super::types::FileType;
+use crate::backend::c;
+use crate::backend::conv::owned_fd;
+use crate::fd::{AsFd, BorrowedFd, OwnedFd};
+use crate::ffi::{CStr, CString};
+use crate::fs::{fcntl_getfl, openat, Mode, OFlags};
+#[cfg(not(target_os = "vita"))]
+use crate::fs::{fstat, Stat};
+#[cfg(not(any(
+    solarish,
+    target_os = "haiku",
+    target_os = "netbsd",
+    target_os = "nto",
+    target_os = "redox",
+    target_os = "vita",
+    target_os = "wasi",
+)))]
+use crate::fs::{fstatfs, StatFs};
+#[cfg(not(any(
+    solarish,
+    target_os = "haiku",
+    target_os = "redox",
+    target_os = "vita",
+    target_os = "wasi"
+)))]
+use crate::fs::{fstatvfs, StatVfs};
+use crate::io;
+#[cfg(not(any(target_os = "fuchsia", target_os = "vita", target_os = "wasi")))]
+#[cfg(feature = "process")]
+use crate::process::fchdir;
+use alloc::borrow::ToOwned;
+#[cfg(not(any(linux_like, target_os = "hurd")))]
+use c::readdir as libc_readdir;
+#[cfg(any(linux_like, target_os = "hurd"))]
+use c::readdir64 as libc_readdir;
+use core::fmt;
+use core::ptr::NonNull;
+use libc_errno::{errno, set_errno, Errno};
+
+/// `DIR*`
+pub struct Dir {
+    /// The `libc` `DIR` pointer.
+    libc_dir: NonNull<c::DIR>,
+
+    /// Have we seen any errors in this iteration?
+    any_errors: bool,
+}
+
+impl Dir {
+    /// Take ownership of `fd` and construct a `Dir` that reads entries from
+    /// the given directory file descriptor.
+    #[inline]
+    pub fn new<Fd: Into<OwnedFd>>(fd: Fd) -> io::Result<Self> {
+        Self::_new(fd.into())
+    }
+
+    #[inline]
+    fn _new(fd: OwnedFd) -> io::Result<Self> {
+        let raw = owned_fd(fd);
+        unsafe {
+            let libc_dir = c::fdopendir(raw);
+
+            if let Some(libc_dir) = NonNull::new(libc_dir) {
+                Ok(Self {
+                    libc_dir,
+                    any_errors: false,
+                })
+            } else {
+                let err = io::Errno::last_os_error();
+                let _ = c::close(raw);
+                Err(err)
+            }
+        }
+    }
+
+    /// Borrow `fd` and 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]
+    #[allow(unused_mut)]
+    fn _read_from(fd: BorrowedFd<'_>) -> io::Result<Self> {
+        let mut any_errors = false;
+
+        // 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 = match openat(fd, cstr!("."), flags | OFlags::CLOEXEC, Mode::empty()) {
+            Ok(fd) => fd,
+            #[cfg(not(target_os = "wasi"))]
+            Err(io::Errno::NOENT) => {
+                // If "." doesn't exist, it means the directory was removed.
+                // We treat that as iterating through a directory with no
+                // entries.
+                any_errors = true;
+                crate::io::dup(fd)?
+            }
+            Err(err) => return Err(err),
+        };
+
+        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,
+                    any_errors,
+                })
+            } else {
+                let err = io::Errno::last_os_error();
+                let _ = c::close(raw);
+                Err(err)
+            }
+        }
+    }
+
+    /// `rewinddir(self)`
+    #[inline]
+    pub fn rewind(&mut self) {
+        self.any_errors = false;
+        unsafe { c::rewinddir(self.libc_dir.as_ptr()) }
+    }
+
+    /// `readdir(self)`, where `None` means the end of the directory.
+    pub fn read(&mut self) -> Option<io::Result<DirEntry>> {
+        // If we've seen errors, don't continue to try to read anyting further.
+        if self.any_errors {
+            return None;
+        }
+
+        set_errno(Errno(0));
+        let dirent_ptr = unsafe { libc_readdir(self.libc_dir.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.
+                self.any_errors = true;
+                Some(Err(io::Errno(curr_errno)))
+            }
+        } else {
+            // We successfully read an entry.
+            unsafe {
+                let dirent = &*dirent_ptr;
+
+                // 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);
+
+                let result = DirEntry {
+                    #[cfg(not(any(
+                        solarish,
+                        target_os = "aix",
+                        target_os = "haiku",
+                        target_os = "nto",
+                        target_os = "vita"
+                    )))]
+                    d_type: dirent.d_type,
+
+                    #[cfg(not(any(freebsdlike, netbsdlike, target_os = "vita")))]
+                    d_ino: dirent.d_ino,
+
+                    #[cfg(any(freebsdlike, netbsdlike))]
+                    d_fileno: dirent.d_fileno,
+
+                    name: CStr::from_ptr(dirent.d_name.as_ptr()).to_owned(),
+                };
+
+                Some(Ok(result))
+            }
+        }
+    }
+
+    /// `fstat(self)`
+    #[cfg(not(target_os = "vita"))]
+    #[inline]
+    pub fn stat(&self) -> io::Result<Stat> {
+        fstat(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.libc_dir.as_ptr())) })
+    }
+
+    /// `fstatfs(self)`
+    #[cfg(not(any(
+        solarish,
+        target_os = "haiku",
+        target_os = "netbsd",
+        target_os = "nto",
+        target_os = "redox",
+        target_os = "vita",
+        target_os = "wasi",
+    )))]
+    #[inline]
+    pub fn statfs(&self) -> io::Result<StatFs> {
+        fstatfs(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.libc_dir.as_ptr())) })
+    }
+
+    /// `fstatvfs(self)`
+    #[cfg(not(any(
+        solarish,
+        target_os = "haiku",
+        target_os = "redox",
+        target_os = "vita",
+        target_os = "wasi"
+    )))]
+    #[inline]
+    pub fn statvfs(&self) -> io::Result<StatVfs> {
+        fstatvfs(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.libc_dir.as_ptr())) })
+    }
+
+    /// `fchdir(self)`
+    #[cfg(feature = "process")]
+    #[cfg(not(any(target_os = "fuchsia", target_os = "vita", target_os = "wasi")))]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "process")))]
+    #[inline]
+    pub fn chdir(&self) -> io::Result<()> {
+        fchdir(unsafe { BorrowedFd::borrow_raw(c::dirfd(self.libc_dir.as_ptr())) })
+    }
+}
+
+/// `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.libc_dir.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 {
+        let mut s = f.debug_struct("Dir");
+        #[cfg(not(target_os = "vita"))]
+        s.field("fd", unsafe { &c::dirfd(self.libc_dir.as_ptr()) });
+        s.finish()
+    }
+}
+
+/// `struct dirent`
+#[derive(Debug)]
+pub struct DirEntry {
+    #[cfg(not(any(
+        solarish,
+        target_os = "aix",
+        target_os = "haiku",
+        target_os = "nto",
+        target_os = "vita"
+    )))]
+    d_type: u8,
+
+    #[cfg(not(any(freebsdlike, netbsdlike, target_os = "vita")))]
+    d_ino: c::ino_t,
+
+    #[cfg(any(freebsdlike, netbsdlike))]
+    d_fileno: c::ino_t,
+
+    name: CString,
+}
+
+impl DirEntry {
+    /// Returns the file name of this directory entry.
+    #[inline]
+    pub fn file_name(&self) -> &CStr {
+        &self.name
+    }
+
+    /// Returns the type of this directory entry.
+    #[cfg(not(any(
+        solarish,
+        target_os = "aix",
+        target_os = "haiku",
+        target_os = "nto",
+        target_os = "vita"
+    )))]
+    #[inline]
+    pub fn file_type(&self) -> FileType {
+        FileType::from_dirent_d_type(self.d_type)
+    }
+
+    /// Return the inode number of this directory entry.
+    #[cfg(not(any(freebsdlike, netbsdlike, target_os = "vita")))]
+    #[inline]
+    pub fn ino(&self) -> u64 {
+        self.d_ino as u64
+    }
+
+    /// Return the inode number of this directory entry.
+    #[cfg(any(freebsdlike, netbsdlike))]
+    #[inline]
+    pub fn ino(&self) -> u64 {
+        #[allow(clippy::useless_conversion)]
+        self.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;
+
+    // Check that the basic layouts match.
+    #[cfg(test)]
+    {
+        assert_eq_size!(libc_dirent, c::dirent);
+        assert_eq_size!(libc_dirent, 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,
+            )
+        }
+    );
+}
+
+#[test]
+fn dir_iterator_handles_io_errors() {
+    // create a dir, keep the FD, then delete the dir
+    let tmp = tempfile::tempdir().unwrap();
+    let fd = crate::fs::openat(
+        crate::fs::CWD,
+        tmp.path(),
+        crate::fs::OFlags::RDONLY | crate::fs::OFlags::CLOEXEC,
+        crate::fs::Mode::empty(),
+    )
+    .unwrap();
+
+    let file_fd = crate::fs::openat(
+        &fd,
+        tmp.path().join("test.txt"),
+        crate::fs::OFlags::WRONLY | crate::fs::OFlags::CREATE,
+        crate::fs::Mode::RWXU,
+    )
+    .unwrap();
+
+    let mut dir = Dir::read_from(&fd).unwrap();
+
+    // Reach inside the `Dir` and replace its directory with a file, which
+    // will cause the subsequent `readdir` to fail.
+    unsafe {
+        let raw_fd = c::dirfd(dir.libc_dir.as_ptr());
+        let mut owned_fd: crate::fd::OwnedFd = crate::fd::FromRawFd::from_raw_fd(raw_fd);
+        crate::io::dup2(&file_fd, &mut owned_fd).unwrap();
+        core::mem::forget(owned_fd);
+    }
+
+    // FreeBSD and macOS seem to read some directory entries before we call
+    // `.next()`.
+    #[cfg(any(apple, freebsdlike))]
+    {
+        dir.rewind();
+    }
+
+    assert!(matches!(dir.next(), Some(Err(_))));
+    assert!(dir.next().is_none());
+}