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use crate::fs::{errors, read_link_impl};
#[cfg(racy_asserts)]
use crate::fs::{map_result, read_link_unchecked, stat, FollowSymlinks};
use std::path::{Path, PathBuf};
use std::{fs, io};
#[cfg_attr(not(racy_asserts), allow(clippy::let_and_return))]
#[inline]
pub fn read_link_contents(start: &fs::File, path: &Path) -> io::Result<PathBuf> {
let result = read_link_impl(start, path);
#[cfg(racy_asserts)]
let unchecked = read_link_unchecked(start, path, PathBuf::new());
#[cfg(racy_asserts)]
check_read_link(start, path, &result, &unchecked);
result
}
#[cfg_attr(not(racy_asserts), allow(clippy::let_and_return))]
#[inline]
pub fn read_link(start: &fs::File, path: &Path) -> io::Result<PathBuf> {
let result = read_link_contents(start, path);
if let Ok(path) = &result {
if path.has_root() {
return Err(errors::escape_attempt());
}
}
result
}
#[cfg(racy_asserts)]
#[allow(clippy::enum_glob_use)]
fn check_read_link(
start: &fs::File,
path: &Path,
result: &io::Result<PathBuf>,
unchecked: &io::Result<PathBuf>,
) {
use io::ErrorKind::*;
match (map_result(result), map_result(unchecked)) {
(Ok(target), Ok(unchecked_target)) => {
assert_eq!(target, unchecked_target);
}
(Err((PermissionDenied, message)), _) => {
match map_result(&stat(start, path, FollowSymlinks::No)) {
Err((PermissionDenied, canon_message)) => {
assert_eq!(message, canon_message);
}
_ => panic!("read_link failed where canonicalize succeeded"),
}
}
(Err((_kind, _message)), Err((_unchecked_kind, _unchecked_message))) => {
}
other => panic!(
"unexpected result from read_link start='{:?}', path='{}':\n{:#?}",
start,
path.display(),
other,
),
}
}
#[cfg(not(windows))]
#[test]
fn test_read_link_contents() {
use io_lifetimes::AsFilelike;
let td = cap_tempfile::tempdir(cap_tempfile::ambient_authority()).unwrap();
let td_view = &td.as_filelike_view::<std::fs::File>();
let valid = [
"relative/path",
"/some/absolute/path",
"/",
"../",
"basepath",
];
for case in valid {
let linkname = Path::new("linkname");
crate::fs::symlink_contents(case, td_view, linkname).unwrap();
let contents = crate::fs::read_link_contents(td_view, linkname).unwrap();
assert_eq!(contents.to_str().unwrap(), case);
crate::fs::remove_file(td_view, linkname).unwrap();
}
}