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use crate::sys::osdir::OsDir;
use crate::{Error, Result};
use std::os::unix::prelude::AsRawFd;
pub(crate) fn unlink_file(dirfd: &OsDir, path: &str) -> Result<()> {
use yanix::file::{unlinkat, AtFlags};
match unsafe { unlinkat(dirfd.as_raw_fd(), path, AtFlags::empty()) } {
Err(err) => {
let raw_errno = err.raw_os_error().unwrap();
// Non-Linux implementations may return EPERM when attempting to remove a
// directory without REMOVEDIR. While that's what POSIX specifies, it's
// less useful. Adjust this to EISDIR. It doesn't matter that this is not
// atomic with the unlinkat, because if the file is removed and a directory
// is created before fstatat sees it, we're racing with that change anyway
// and unlinkat could have legitimately seen the directory if the race had
// turned out differently.
use yanix::file::{fstatat, FileType};
if raw_errno == libc::EPERM {
match unsafe { fstatat(dirfd.as_raw_fd(), path, AtFlags::SYMLINK_NOFOLLOW) } {
Ok(stat) => {
if FileType::from_stat_st_mode(stat.st_mode) == FileType::Directory {
return Err(Error::Isdir);
}
}
Err(err) => {
tracing::debug!("path_unlink_file fstatat error: {:?}", err);
}
}
}
Err(err.into())
}
Ok(()) => Ok(()),
}
}
pub(crate) fn symlink(old_path: &str, new_dirfd: &OsDir, new_path: &str) -> Result<()> {
use yanix::file::{fstatat, symlinkat, AtFlags};
tracing::debug!("path_symlink old_path = {:?}", old_path);
tracing::debug!(
"path_symlink (new_dirfd, new_path) = ({:?}, {:?})",
new_dirfd,
new_path
);
match unsafe { symlinkat(old_path, new_dirfd.as_raw_fd(), new_path) } {
Err(err) => {
if err.raw_os_error().unwrap() == libc::ENOTDIR {
// On BSD, symlinkat returns ENOTDIR when it should in fact
// return a EEXIST. It seems that it gets confused with by
// the trailing slash in the target path. Thus, we strip
// the trailing slash and check if the path exists, and
// adjust the error code appropriately.
let new_path = new_path.trim_end_matches('/');
match unsafe { fstatat(new_dirfd.as_raw_fd(), new_path, AtFlags::SYMLINK_NOFOLLOW) }
{
Ok(_) => return Err(Error::Exist),
Err(err) => {
tracing::debug!("path_symlink fstatat error: {:?}", err);
}
}
}
Err(err.into())
}
Ok(()) => Ok(()),
}
}
pub(crate) fn rename(
old_dirfd: &OsDir,
old_path: &str,
new_dirfd: &OsDir,
new_path: &str,
) -> Result<()> {
use yanix::file::{fstatat, renameat, AtFlags};
match unsafe {
renameat(
old_dirfd.as_raw_fd(),
old_path,
new_dirfd.as_raw_fd(),
new_path,
)
} {
Err(err) => {
// Currently, this is verified to be correct on macOS, where
// ENOENT can be returned in case when we try to rename a file
// into a name with a trailing slash. On macOS, if the latter does
// not exist, an ENOENT is thrown, whereas on Linux we observe the
// correct behaviour of throwing an ENOTDIR since the destination is
// indeed not a directory.
//
// TODO
// Verify on other BSD-based OSes.
if err.raw_os_error().unwrap() == libc::ENOENT {
// check if the source path exists
match unsafe { fstatat(old_dirfd.as_raw_fd(), old_path, AtFlags::SYMLINK_NOFOLLOW) }
{
Ok(_) => {
// check if destination contains a trailing slash
if new_path.contains('/') {
return Err(Error::Notdir);
} else {
return Err(Error::Noent);
}
}
Err(err) => {
tracing::debug!("path_rename fstatat error: {:?}", err);
}
}
}
Err(err.into())
}
Ok(()) => Ok(()),
}
}