unix.rs source code [crates/std/src/sys/fs/unix.rs]

1	#![allow(nonstandard_style)]
2	#![allow(unsafe_op_in_unsafe_fn)]
3	// miri has some special hacks here that make things unused.
4	#![cfg_attr(miri, allow(unused))]
5
6	#[cfg(test)]
7	mod tests;
8
9	#[cfg(all(target_os = "linux", target_env = "gnu"))]
10	use libc::c_char;
11	#[cfg(any(
12	all(target_os = "linux", not(target_env = "musl")),
13	target_os = "android",
14	target_os = "fuchsia",
15	target_os = "hurd"
16	))]
17	use libc::dirfd;
18	#[cfg(target_os = "fuchsia")]
19	use libc::fstatat as fstatat64;
20	#[cfg(any(all(target_os = "linux", not(target_env = "musl")), target_os = "hurd"))]
21	use libc::fstatat64;
22	#[cfg(any(
23	target_os = "android",
24	target_os = "solaris",
25	target_os = "fuchsia",
26	target_os = "redox",
27	target_os = "illumos",
28	target_os = "aix",
29	target_os = "nto",
30	target_os = "vita",
31	all(target_os = "linux", target_env = "musl"),
32	))]
33	use libc::readdir as readdir64;
34	#[cfg(not(any(
35	target_os = "android",
36	target_os = "linux",
37	target_os = "solaris",
38	target_os = "illumos",
39	target_os = "l4re",
40	target_os = "fuchsia",
41	target_os = "redox",
42	target_os = "aix",
43	target_os = "nto",
44	target_os = "vita",
45	target_os = "hurd",
46	)))]
47	use libc::readdir_r as readdir64_r;
48	#[cfg(any(all(target_os = "linux", not(target_env = "musl")), target_os = "hurd"))]
49	use libc::readdir64;
50	#[cfg(target_os = "l4re")]
51	use libc::readdir64_r;
52	use libc::{c_int, mode_t};
53	#[cfg(target_os = "android")]
54	use libc::{
55	dirent as dirent64, fstat as fstat64, fstatat as fstatat64, ftruncate64, lseek64,
56	lstat as lstat64, off64_t, open as open64, stat as stat64,
57	};
58	#[cfg(not(any(
59	all(target_os = "linux", not(target_env = "musl")),
60	target_os = "l4re",
61	target_os = "android",
62	target_os = "hurd",
63	)))]
64	use libc::{
65	dirent as dirent64, fstat as fstat64, ftruncate as ftruncate64, lseek as lseek64,
66	lstat as lstat64, off_t as off64_t, open as open64, stat as stat64,
67	};
68	#[cfg(any(
69	all(target_os = "linux", not(target_env = "musl")),
70	target_os = "l4re",
71	target_os = "hurd"
72	))]
73	use libc::{dirent64, fstat64, ftruncate64, lseek64, lstat64, off64_t, open64, stat64};
74
75	use crate::ffi::{CStr, OsStr, OsString};
76	use crate::fmt::{self, Write as _};
77	use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom};
78	use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd};
79	use crate::os::unix::prelude::*;
80	use crate::path::{Path, PathBuf};
81	use crate::sync::Arc;
82	use crate::sys::common::small_c_string::run_path_with_cstr;
83	use crate::sys::fd::FileDesc;
84	pub use crate::sys::fs::common::exists;
85	use crate::sys::time::SystemTime;
86	#[cfg(all(target_os = "linux", target_env = "gnu"))]
87	use crate::sys::weak::syscall;
88	#[cfg(target_os = "android")]
89	use crate::sys::weak::weak;
90	use crate::sys::{cvt, cvt_r};
91	use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
92	use crate::{mem, ptr};
93
94	pub struct File(FileDesc);
95
96	// FIXME: This should be available on Linux with all `target_env`.
97	// But currently only glibc exposes `statx` fn and structs.
98	// We don't want to import unverified raw C structs here directly.
99	// https://github.com/rust-lang/rust/pull/67774
100	macro_rules! cfg_has_statx {
101	({ $($then_tt:tt)* } else { $($else_tt:tt)* }) => {
102	cfg_if::cfg_if! {
103	if #[cfg(all(target_os = "linux", target_env = "gnu"))] {
104	$($then_tt)*
105	} else {
106	$($else_tt)*
107	}
108	}
109	};
110	($($block_inner:tt)*) => {
111	#[cfg(all(target_os = "linux", target_env = "gnu"))]
112	{
113	$($block_inner)*
114	}
115	};
116	}
117
118	cfg_has_statx! {{
119	#[derive(Clone)]
120	pub struct FileAttr {
121	stat: stat64,
122	statx_extra_fields: Option<StatxExtraFields>,
123	}
124
125	#[derive(Clone)]
126	struct StatxExtraFields {
127	// This is needed to check if btime is supported by the filesystem.
128	stx_mask: u32,
129	stx_btime: libc::statx_timestamp,
130	// With statx, we can overcome 32-bit `time_t` too.
131	#[cfg(target_pointer_width = "32")]
132	stx_atime: libc::statx_timestamp,
133	#[cfg(target_pointer_width = "32")]
134	stx_ctime: libc::statx_timestamp,
135	#[cfg(target_pointer_width = "32")]
136	stx_mtime: libc::statx_timestamp,
137
138	}
139
140	// We prefer `statx` on Linux if available, which contains file creation time,
141	// as well as 64-bit timestamps of all kinds.
142	// Default `stat64` contains no creation time and may have 32-bit `time_t`.
143	unsafe fn try_statx(
144	fd: c_int,
145	path: *const c_char,
146	flags: i32,
147	mask: u32,
148	) -> Option<io::Result<FileAttr>> {
149	use crate::sync::atomic::{AtomicU8, Ordering};
150
151	// Linux kernel prior to 4.11 or glibc prior to glibc 2.28 don't support `statx`.
152	// We check for it on first failure and remember availability to avoid having to
153	// do it again.
154	#[repr(u8)]
155	enum STATX_STATE{ Unknown = `0`, Present, Unavailable }
156	static STATX_SAVED_STATE: AtomicU8 = AtomicU8::new(STATX_STATE::Unknown as u8);
157
158	syscall! {
159	fn statx(
160	fd: c_int,
161	pathname: *const c_char,
162	flags: c_int,
163	mask: libc::c_uint,
164	statxbuf: *mut libc::statx
165	) -> c_int
166	}
167
168	let statx_availability = STATX_SAVED_STATE.load(Ordering::Relaxed);
169	if statx_availability == STATX_STATE::Unavailable as u8 {
170	return None;
171	}
172
173	let mut buf: libc::statx = mem::zeroed();
174	if let Err(err) = cvt(statx(fd, path, flags, mask, &mut buf)) {
175	if STATX_SAVED_STATE.load(Ordering::Relaxed) == STATX_STATE::Present as u8 {
176	return Some(Err(err));
177	}
178
179	// We're not yet entirely sure whether `statx` is usable on this kernel
180	// or not. Syscalls can return errors from things other than the kernel
181	// per se, e.g. `EPERM` can be returned if seccomp is used to block the
182	// syscall, or `ENOSYS` might be returned from a faulty FUSE driver.
183	//
184	// Availability is checked by performing a call which expects `EFAULT`
185	// if the syscall is usable.
186	//
187	// See: https://github.com/rust-lang/rust/issues/65662
188	//
189	// FIXME what about transient conditions like `ENOMEM`?
190	let err2 = cvt(statx(`0`, ptr::null(), `0`, libc::STATX_BASIC_STATS \| libc::STATX_BTIME, ptr::null_mut()))
191	.err()
192	.and_then(\|e\| e.raw_os_error());
193	if err2 == Some(libc::EFAULT) {
194	STATX_SAVED_STATE.store(STATX_STATE::Present as u8, Ordering::Relaxed);
195	return Some(Err(err));
196	} else {
197	STATX_SAVED_STATE.store(STATX_STATE::Unavailable as u8, Ordering::Relaxed);
198	return None;
199	}
200	}
201	if statx_availability == STATX_STATE::Unknown as u8 {
202	STATX_SAVED_STATE.store(STATX_STATE::Present as u8, Ordering::Relaxed);
203	}
204
205	// We cannot fill `stat64` exhaustively because of private padding fields.
206	let mut stat: stat64 = mem::zeroed();
207	// `c_ulong` on gnu-mips, `dev_t` otherwise
208	stat.st_dev = libc::makedev(buf.stx_dev_major, buf.stx_dev_minor) as _;
209	stat.st_ino = buf.stx_ino as libc::ino64_t;
210	stat.st_nlink = buf.stx_nlink as libc::nlink_t;
211	stat.st_mode = buf.stx_mode as libc::mode_t;
212	stat.st_uid = buf.stx_uid as libc::uid_t;
213	stat.st_gid = buf.stx_gid as libc::gid_t;
214	stat.st_rdev = libc::makedev(buf.stx_rdev_major, buf.stx_rdev_minor) as _;
215	stat.st_size = buf.stx_size as off64_t;
216	stat.st_blksize = buf.stx_blksize as libc::blksize_t;
217	stat.st_blocks = buf.stx_blocks as libc::blkcnt64_t;
218	stat.st_atime = buf.stx_atime.tv_sec as libc::time_t;
219	// `i64` on gnu-x86_64-x32, `c_ulong` otherwise.
220	stat.st_atime_nsec = buf.stx_atime.tv_nsec as _;
221	stat.st_mtime = buf.stx_mtime.tv_sec as libc::time_t;
222	stat.st_mtime_nsec = buf.stx_mtime.tv_nsec as _;
223	stat.st_ctime = buf.stx_ctime.tv_sec as libc::time_t;
224	stat.st_ctime_nsec = buf.stx_ctime.tv_nsec as _;
225
226	let extra = StatxExtraFields {
227	stx_mask: buf.stx_mask,
228	stx_btime: buf.stx_btime,
229	// Store full times to avoid 32-bit `time_t` truncation.
230	#[cfg(target_pointer_width = "32")]
231	stx_atime: buf.stx_atime,
232	#[cfg(target_pointer_width = "32")]
233	stx_ctime: buf.stx_ctime,
234	#[cfg(target_pointer_width = "32")]
235	stx_mtime: buf.stx_mtime,
236	};
237
238	Some(Ok(FileAttr { stat, statx_extra_fields: Some(extra) }))
239	}
240
241	} else {
242	#[derive(Clone)]
243	pub struct FileAttr {
244	stat: stat64,
245	}
246	}}
247
248	// all DirEntry's will have a reference to this struct
249	struct InnerReadDir {
250	dirp: Dir,
251	root: PathBuf,
252	}
253
254	pub struct ReadDir {
255	inner: Arc<InnerReadDir>,
256	end_of_stream: bool,
257	}
258
259	impl ReadDir {
260	fn new(inner: InnerReadDir) -> Self {
261	Self { inner: Arc::new(data:inner), end_of_stream: `false` }
262	}
263	}
264
265	struct Dir(*mut libc::DIR);
266
267	unsafe impl Send for Dir {}
268	unsafe impl Sync for Dir {}
269
270	#[cfg(any(
271	target_os = "android",
272	target_os = "linux",
273	target_os = "solaris",
274	target_os = "illumos",
275	target_os = "fuchsia",
276	target_os = "redox",
277	target_os = "aix",
278	target_os = "nto",
279	target_os = "vita",
280	target_os = "hurd",
281	))]
282	pub struct DirEntry {
283	dir: Arc<InnerReadDir>,
284	entry: dirent64_min,
285	// We need to store an owned copy of the entry name on platforms that use
286	// readdir() (not readdir_r()), because a) struct dirent may use a flexible
287	// array to store the name, b) it lives only until the next readdir() call.
288	name: crate::ffi::CString,
289	}
290
291	// Define a minimal subset of fields we need from `dirent64`, especially since
292	// we're not using the immediate `d_name` on these targets. Keeping this as an
293	// `entry` field in `DirEntry` helps reduce the `cfg` boilerplate elsewhere.
294	#[cfg(any(
295	target_os = "android",
296	target_os = "linux",
297	target_os = "solaris",
298	target_os = "illumos",
299	target_os = "fuchsia",
300	target_os = "redox",
301	target_os = "aix",
302	target_os = "nto",
303	target_os = "vita",
304	target_os = "hurd",
305	))]
306	struct dirent64_min {
307	d_ino: u64,
308	#[cfg(not(any(
309	target_os = "solaris",
310	target_os = "illumos",
311	target_os = "aix",
312	target_os = "nto",
313	target_os = "vita",
314	)))]
315	d_type: u8,
316	}
317
318	#[cfg(not(any(
319	target_os = "android",
320	target_os = "linux",
321	target_os = "solaris",
322	target_os = "illumos",
323	target_os = "fuchsia",
324	target_os = "redox",
325	target_os = "aix",
326	target_os = "nto",
327	target_os = "vita",
328	target_os = "hurd",
329	)))]
330	pub struct DirEntry {
331	dir: Arc<InnerReadDir>,
332	// The full entry includes a fixed-length `d_name`.
333	entry: dirent64,
334	}
335
336	#[derive(Clone)]
337	pub struct OpenOptions {
338	// generic
339	read: bool,
340	write: bool,
341	append: bool,
342	truncate: bool,
343	create: bool,
344	create_new: bool,
345	// system-specific
346	custom_flags: i32,
347	mode: mode_t,
348	}
349
350	#[derive(Clone, PartialEq, Eq)]
351	pub struct FilePermissions {
352	mode: mode_t,
353	}
354
355	#[derive(Copy, Clone, Debug, Default)]
356	pub struct FileTimes {
357	accessed: Option<SystemTime>,
358	modified: Option<SystemTime>,
359	#[cfg(target_vendor = "apple")]
360	created: Option<SystemTime>,
361	}
362
363	#[derive(Copy, Clone, Eq)]
364	pub struct FileType {
365	mode: mode_t,
366	}
367
368	impl PartialEq for FileType {
369	fn eq(&self, other: &Self) -> bool {
370	self.masked() == other.masked()
371	}
372	}
373
374	impl core::hash::Hash for FileType {
375	fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
376	self.masked().hash(state);
377	}
378	}
379
380	pub struct DirBuilder {
381	mode: mode_t,
382	}
383
384	#[derive(Copy, Clone)]
385	struct Mode(mode_t);
386
387	cfg_has_statx! {{
388	impl FileAttr {
389	fn from_stat64(stat: stat64) -> Self {
390	Self { stat, statx_extra_fields: None }
391	}
392
393	#[cfg(target_pointer_width = "32")]
394	pub fn stx_mtime(&self) -> Option<&libc::statx_timestamp> {
395	if let Some(ext) = &self.statx_extra_fields {
396	if (ext.stx_mask & libc::STATX_MTIME) != `0` {
397	return Some(&ext.stx_mtime);
398	}
399	}
400	None
401	}
402
403	#[cfg(target_pointer_width = "32")]
404	pub fn stx_atime(&self) -> Option<&libc::statx_timestamp> {
405	if let Some(ext) = &self.statx_extra_fields {
406	if (ext.stx_mask & libc::STATX_ATIME) != `0` {
407	return Some(&ext.stx_atime);
408	}
409	}
410	None
411	}
412
413	#[cfg(target_pointer_width = "32")]
414	pub fn stx_ctime(&self) -> Option<&libc::statx_timestamp> {
415	if let Some(ext) = &self.statx_extra_fields {
416	if (ext.stx_mask & libc::STATX_CTIME) != `0` {
417	return Some(&ext.stx_ctime);
418	}
419	}
420	None
421	}
422	}
423	} else {
424	impl FileAttr {
425	fn from_stat64(stat: stat64) -> Self {
426	Self { stat }
427	}
428	}
429	}}
430
431	impl FileAttr {
432	pub fn size(&self) -> u64 {
433	self.stat.st_size as u64
434	}
435	pub fn perm(&self) -> FilePermissions {
436	FilePermissions { mode: (self.stat.st_mode as mode_t) }
437	}
438
439	pub fn file_type(&self) -> FileType {
440	FileType { mode: self.stat.st_mode as mode_t }
441	}
442	}
443
444	#[cfg(target_os = "netbsd")]
445	impl FileAttr {
446	pub fn modified(&self) -> io::Result<SystemTime> {
447	SystemTime::new(self.stat.st_mtime as i64, self.stat.st_mtimensec as i64)
448	}
449
450	pub fn accessed(&self) -> io::Result<SystemTime> {
451	SystemTime::new(self.stat.st_atime as i64, self.stat.st_atimensec as i64)
452	}
453
454	pub fn created(&self) -> io::Result<SystemTime> {
455	SystemTime::new(self.stat.st_birthtime as i64, self.stat.st_birthtimensec as i64)
456	}
457	}
458
459	#[cfg(target_os = "aix")]
460	impl FileAttr {
461	pub fn modified(&self) -> io::Result<SystemTime> {
462	SystemTime::new(self.stat.st_mtime.tv_sec as i64, self.stat.st_mtime.tv_nsec as i64)
463	}
464
465	pub fn accessed(&self) -> io::Result<SystemTime> {
466	SystemTime::new(self.stat.st_atime.tv_sec as i64, self.stat.st_atime.tv_nsec as i64)
467	}
468
469	pub fn created(&self) -> io::Result<SystemTime> {
470	SystemTime::new(self.stat.st_ctime.tv_sec as i64, self.stat.st_ctime.tv_nsec as i64)
471	}
472	}
473
474	#[cfg(not(any(target_os = "netbsd", target_os = "nto", target_os = "aix")))]
475	impl FileAttr {
476	#[cfg(not(any(
477	target_os = "vxworks",
478	target_os = "espidf",
479	target_os = "horizon",
480	target_os = "vita",
481	target_os = "hurd",
482	target_os = "rtems",
483	target_os = "nuttx",
484	)))]
485	pub fn modified(&self) -> io::Result<SystemTime> {
486	#[cfg(target_pointer_width = "32")]
487	cfg_has_statx! {
488	if let Some(mtime) = self.stx_mtime() {
489	return SystemTime::new(mtime.tv_sec, mtime.tv_nsec as i64);
490	}
491	}
492
493	SystemTime::new(self.stat.st_mtime as i64, self.stat.st_mtime_nsec as i64)
494	}
495
496	#[cfg(any(
497	target_os = "vxworks",
498	target_os = "espidf",
499	target_os = "vita",
500	target_os = "rtems",
501	))]
502	pub fn modified(&self) -> io::Result<SystemTime> {
503	SystemTime::new(self.stat.st_mtime as i64, `0`)
504	}
505
506	#[cfg(any(target_os = "horizon", target_os = "hurd", target_os = "nuttx"))]
507	pub fn modified(&self) -> io::Result<SystemTime> {
508	SystemTime::new(self.stat.st_mtim.tv_sec as i64, self.stat.st_mtim.tv_nsec as i64)
509	}
510
511	#[cfg(not(any(
512	target_os = "vxworks",
513	target_os = "espidf",
514	target_os = "horizon",
515	target_os = "vita",
516	target_os = "hurd",
517	target_os = "rtems",
518	target_os = "nuttx",
519	)))]
520	pub fn accessed(&self) -> io::Result<SystemTime> {
521	#[cfg(target_pointer_width = "32")]
522	cfg_has_statx! {
523	if let Some(atime) = self.stx_atime() {
524	return SystemTime::new(atime.tv_sec, atime.tv_nsec as i64);
525	}
526	}
527
528	SystemTime::new(self.stat.st_atime as i64, self.stat.st_atime_nsec as i64)
529	}
530
531	#[cfg(any(
532	target_os = "vxworks",
533	target_os = "espidf",
534	target_os = "vita",
535	target_os = "rtems"
536	))]
537	pub fn accessed(&self) -> io::Result<SystemTime> {
538	SystemTime::new(self.stat.st_atime as i64, `0`)
539	}
540
541	#[cfg(any(target_os = "horizon", target_os = "hurd", target_os = "nuttx"))]
542	pub fn accessed(&self) -> io::Result<SystemTime> {
543	SystemTime::new(self.stat.st_atim.tv_sec as i64, self.stat.st_atim.tv_nsec as i64)
544	}
545
546	#[cfg(any(
547	target_os = "freebsd",
548	target_os = "openbsd",
549	target_vendor = "apple",
550	target_os = "cygwin",
551	))]
552	pub fn created(&self) -> io::Result<SystemTime> {
553	SystemTime::new(self.stat.st_birthtime as i64, self.stat.st_birthtime_nsec as i64)
554	}
555
556	#[cfg(not(any(
557	target_os = "freebsd",
558	target_os = "openbsd",
559	target_os = "vita",
560	target_vendor = "apple",
561	target_os = "cygwin",
562	)))]
563	pub fn created(&self) -> io::Result<SystemTime> {
564	cfg_has_statx! {
565	if let Some(ext) = &self.statx_extra_fields {
566	return if (ext.stx_mask & libc::STATX_BTIME) != `0` {
567	SystemTime::new(ext.stx_btime.tv_sec, ext.stx_btime.tv_nsec as i64)
568	} else {
569	Err(io::const_error!(
570	io::ErrorKind::Unsupported,
571	"creation time is not available for the filesystem",
572	))
573	};
574	}
575	}
576
577	Err(io::const_error!(
578	io::ErrorKind::Unsupported,
579	"creation time is not available on this platform currently",
580	))
581	}
582
583	#[cfg(target_os = "vita")]
584	pub fn created(&self) -> io::Result<SystemTime> {
585	SystemTime::new(self.stat.st_ctime as i64, `0`)
586	}
587	}
588
589	#[cfg(target_os = "nto")]
590	impl FileAttr {
591	pub fn modified(&self) -> io::Result<SystemTime> {
592	SystemTime::new(self.stat.st_mtim.tv_sec, self.stat.st_mtim.tv_nsec)
593	}
594
595	pub fn accessed(&self) -> io::Result<SystemTime> {
596	SystemTime::new(self.stat.st_atim.tv_sec, self.stat.st_atim.tv_nsec)
597	}
598
599	pub fn created(&self) -> io::Result<SystemTime> {
600	SystemTime::new(self.stat.st_ctim.tv_sec, self.stat.st_ctim.tv_nsec)
601	}
602	}
603
604	impl AsInner<stat64> for FileAttr {
605	#[inline]
606	fn as_inner(&self) -> &stat64 {
607	&self.stat
608	}
609	}
610
611	impl FilePermissions {
612	pub fn readonly(&self) -> bool {
613	// check if any class (owner, group, others) has write permission
614	self.mode & `0o222` == `0`
615	}
616
617	pub fn set_readonly(&mut self, readonly: bool) {
618	if readonly {
619	// remove write permission for all classes; equivalent to `chmod a-w <file>`
620	self.mode &= !`0o222`;
621	} else {
622	// add write permission for all classes; equivalent to `chmod a+w <file>`
623	self.mode \|= `0o222`;
624	}
625	}
626	pub fn mode(&self) -> u32 {
627	self.mode as u32
628	}
629	}
630
631	impl FileTimes {
632	pub fn set_accessed(&mut self, t: SystemTime) {
633	self.accessed = Some(t);
634	}
635
636	pub fn set_modified(&mut self, t: SystemTime) {
637	self.modified = Some(t);
638	}
639
640	#[cfg(target_vendor = "apple")]
641	pub fn set_created(&mut self, t: SystemTime) {
642	self.created = Some(t);
643	}
644	}
645
646	impl FileType {
647	pub fn is_dir(&self) -> bool {
648	self.is(mode:libc::S_IFDIR)
649	}
650	pub fn is_file(&self) -> bool {
651	self.is(mode:libc::S_IFREG)
652	}
653	pub fn is_symlink(&self) -> bool {
654	self.is(mode:libc::S_IFLNK)
655	}
656
657	pub fn is(&self, mode: mode_t) -> bool {
658	self.masked() == mode
659	}
660
661	fn masked(&self) -> mode_t {
662	self.mode & libc::S_IFMT
663	}
664	}
665
666	impl fmt::Debug for FileType {
667	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
668	let FileType { mode: &u32 } = self;
669	f.debug_struct("FileType").field(name:"mode", &Mode(*mode)).finish()
670	}
671	}
672
673	impl FromInner<u32> for FilePermissions {
674	fn from_inner(mode: u32) -> FilePermissions {
675	FilePermissions { mode: mode as mode_t }
676	}
677	}
678
679	impl fmt::Debug for FilePermissions {
680	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
681	let FilePermissions { mode: &u32 } = self;
682	f.debug_struct("FilePermissions").field(name:"mode", &Mode(*mode)).finish()
683	}
684	}
685
686	impl fmt::Debug for ReadDir {
687	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
688	// This will only be called from std::fs::ReadDir, which will add a "ReadDir()" frame.
689	// Thus the result will be e g 'ReadDir("/home")'
690	fmt::Debug::fmt(&*self.inner.root, f)
691	}
692	}
693
694	impl Iterator for ReadDir {
695	type Item = io::Result<DirEntry>;
696
697	#[cfg(any(
698	target_os = "android",
699	target_os = "linux",
700	target_os = "solaris",
701	target_os = "fuchsia",
702	target_os = "redox",
703	target_os = "illumos",
704	target_os = "aix",
705	target_os = "nto",
706	target_os = "vita",
707	target_os = "hurd",
708	))]
709	fn next(&mut self) -> Option<io::Result<DirEntry>> {
710	use crate::sys::os::{errno, set_errno};
711
712	if self.end_of_stream {
713	return None;
714	}
715
716	unsafe {
717	loop {
718	// As of POSIX.1-2017, readdir() is not required to be thread safe; only
719	// readdir_r() is. However, readdir_r() cannot correctly handle platforms
720	// with unlimited or variable NAME_MAX. Many modern platforms guarantee
721	// thread safety for readdir() as long an individual DIR is not accessed*
722	// concurrently, which is sufficient for Rust.
723	set_errno(`0`);
724	let entry_ptr: *const dirent64 = readdir64(self.inner.dirp.0);
725	if entry_ptr.is_null() {
726	// We either encountered an error, or reached the end. Either way,
727	// the next call to next() should return None.
728	self.end_of_stream = `true`;
729
730	// To distinguish between errors and end-of-directory, we had to clear
731	// errno beforehand to check for an error now.
732	return match errno() {
733	`0` => None,
734	e => Some(Err(Error::from_raw_os_error(e))),
735	};
736	}
737
738	// The dirent64 struct is a weird imaginary thing that isn't ever supposed
739	// to be worked with by value. Its trailing d_name field is declared
740	// variously as [c_char; 256] or [c_char; 1] on different systems but
741	// either way that size is meaningless; only the offset of d_name is
742	// meaningful. The dirent64 pointers that libc returns from readdir64 are
743	// allowed to point to allocations smaller _or_ LARGER than implied by the
744	// definition of the struct.
745	//
746	// As such, we need to be even more careful with dirent64 than if its
747	// contents were "simply" partially initialized data.
748	//
749	// Like for uninitialized contents, converting entry_ptr to `&dirent64`
750	// would not be legal. However, we can use `&raw const (entry_ptr).d_name`*
751	// to refer the fields individually, because that operation is equivalent
752	// to `byte_offset` and thus does not require the full extent of `entry_ptr`*
753	// to be in bounds of the same allocation, only the offset of the field
754	// being referenced.
755
756	// d_name is guaranteed to be null-terminated.
757	let name = CStr::from_ptr((&raw const (*entry_ptr).d_name).cast());
758	let name_bytes = name.to_bytes();
759	if name_bytes == b"." \|\| name_bytes == b".." {
760	continue;
761	}
762
763	// When loading from a field, we can skip the `&raw const`; `(entry_ptr).d_ino` as*
764	// a value expression will do the right thing: `byte_offset` to the field and then
765	// only access those bytes.
766	#[cfg(not(target_os = "vita"))]
767	let entry = dirent64_min {
768	d_ino: (entry_ptr).d_ino as u64*,
769	#[cfg(not(any(
770	target_os = "solaris",
771	target_os = "illumos",
772	target_os = "aix",
773	target_os = "nto",
774	)))]
775	d_type: (*entry_ptr).d_type as u8,
776	};
777
778	#[cfg(target_os = "vita")]
779	let entry = dirent64_min { d_ino: `0u64` };
780
781	return Some(Ok(DirEntry {
782	entry,
783	name: name.to_owned(),
784	dir: Arc::clone(&self.inner),
785	}));
786	}
787	}
788	}
789
790	#[cfg(not(any(
791	target_os = "android",
792	target_os = "linux",
793	target_os = "solaris",
794	target_os = "fuchsia",
795	target_os = "redox",
796	target_os = "illumos",
797	target_os = "aix",
798	target_os = "nto",
799	target_os = "vita",
800	target_os = "hurd",
801	)))]
802	fn next(&mut self) -> Option<io::Result<DirEntry>> {
803	if self.end_of_stream {
804	return None;
805	}
806
807	unsafe {
808	let mut ret = DirEntry { entry: mem::zeroed(), dir: Arc::clone(&self.inner) };
809	let mut entry_ptr = ptr::null_mut();
810	loop {
811	let err = readdir64_r(self.inner.dirp.0, &mut ret.entry, &mut entry_ptr);
812	if err != `0` {
813	if entry_ptr.is_null() {
814	// We encountered an error (which will be returned in this iteration), but
815	// we also reached the end of the directory stream. The `end_of_stream`
816	// flag is enabled to make sure that we return `None` in the next iteration
817	// (instead of looping forever)
818	self.end_of_stream = `true`;
819	}
820	return Some(Err(Error::from_raw_os_error(err)));
821	}
822	if entry_ptr.is_null() {
823	return None;
824	}
825	if ret.name_bytes() != b"." && ret.name_bytes() != b".." {
826	return Some(Ok(ret));
827	}
828	}
829	}
830	}
831	}
832
833	/// Aborts the process if a file desceriptor is not open, if debug asserts are enabled
834	///
835	/// Many IO syscalls can't be fully trusted about EBADF error codes because those
836	/// might get bubbled up from a remote FUSE server rather than the file descriptor
837	/// in the current process being invalid.
838	///
839	/// So we check file flags instead which live on the file descriptor and not the underlying file.
840	/// The downside is that it costs an extra syscall, so we only do it for debug.
841	#[inline]
842	pub(crate) fn debug_assert_fd_is_open(fd: RawFd) {
843	use crate::sys::os::errno;
844
845	// this is similar to assert_unsafe_precondition!() but it doesn't require const
846	if core::ub_checks::check_library_ub() {
847	if unsafe { libc::fcntl(fd, cmd:libc::F_GETFD) } == `-1` && errno() == libc::EBADF {
848	rtabort!("IO Safety violation: owned file descriptor already closed");
849	}
850	}
851	}
852
853	impl Drop for Dir {
854	fn drop(&mut self) {
855	// dirfd isn't supported everywhere
856	#[cfg(not(any(
857	miri,
858	target_os = "redox",
859	target_os = "nto",
860	target_os = "vita",
861	target_os = "hurd",
862	target_os = "espidf",
863	target_os = "horizon",
864	target_os = "vxworks",
865	target_os = "rtems",
866	target_os = "nuttx",
867	)))]
868	{
869	let fd = unsafe { libc::dirfd(self.0) };
870	debug_assert_fd_is_open(fd);
871	}
872	let r = unsafe { libc::closedir(self.0) };
873	assert!(
874	r == `0` \|\| crate::io::Error::last_os_error().is_interrupted(),
875	"unexpected error during closedir: {:?}",
876	crate::io::Error::last_os_error()
877	);
878	}
879	}
880
881	impl DirEntry {
882	pub fn path(&self) -> PathBuf {
883	self.dir.root.join(self.file_name_os_str())
884	}
885
886	pub fn file_name(&self) -> OsString {
887	self.file_name_os_str().to_os_string()
888	}
889
890	#[cfg(all(
891	any(
892	all(target_os = "linux", not(target_env = "musl")),
893	target_os = "android",
894	target_os = "fuchsia",
895	target_os = "hurd"
896	),
897	not(miri) // no dirfd on Miri
898	))]
899	pub fn metadata(&self) -> io::Result<FileAttr> {
900	let fd = cvt(unsafe { dirfd(self.dir.dirp.0) })?;
901	let name = self.name_cstr().as_ptr();
902
903	cfg_has_statx! {
904	if let Some(ret) = unsafe { try_statx(
905	fd,
906	name,
907	libc::AT_SYMLINK_NOFOLLOW \| libc::AT_STATX_SYNC_AS_STAT,
908	libc::STATX_BASIC_STATS \| libc::STATX_BTIME,
909	) } {
910	return ret;
911	}
912	}
913
914	let mut stat: stat64 = unsafe { mem::zeroed() };
915	cvt(unsafe { fstatat64(fd, name, &mut stat, libc::AT_SYMLINK_NOFOLLOW) })?;
916	Ok(FileAttr::from_stat64(stat))
917	}
918
919	#[cfg(any(
920	not(any(
921	all(target_os = "linux", not(target_env = "musl")),
922	target_os = "android",
923	target_os = "fuchsia",
924	target_os = "hurd",
925	)),
926	miri
927	))]
928	pub fn metadata(&self) -> io::Result<FileAttr> {
929	lstat(&self.path())
930	}
931
932	#[cfg(any(
933	target_os = "solaris",
934	target_os = "illumos",
935	target_os = "haiku",
936	target_os = "vxworks",
937	target_os = "aix",
938	target_os = "nto",
939	target_os = "vita",
940	))]
941	pub fn file_type(&self) -> io::Result<FileType> {
942	self.metadata().map(\|m\| m.file_type())
943	}
944
945	#[cfg(not(any(
946	target_os = "solaris",
947	target_os = "illumos",
948	target_os = "haiku",
949	target_os = "vxworks",
950	target_os = "aix",
951	target_os = "nto",
952	target_os = "vita",
953	)))]
954	pub fn file_type(&self) -> io::Result<FileType> {
955	match self.entry.d_type {
956	libc::DT_CHR => Ok(FileType { mode: libc::S_IFCHR }),
957	libc::DT_FIFO => Ok(FileType { mode: libc::S_IFIFO }),
958	libc::DT_LNK => Ok(FileType { mode: libc::S_IFLNK }),
959	libc::DT_REG => Ok(FileType { mode: libc::S_IFREG }),
960	libc::DT_SOCK => Ok(FileType { mode: libc::S_IFSOCK }),
961	libc::DT_DIR => Ok(FileType { mode: libc::S_IFDIR }),
962	libc::DT_BLK => Ok(FileType { mode: libc::S_IFBLK }),
963	_ => self.metadata().map(\|m\| m.file_type()),
964	}
965	}
966
967	#[cfg(any(
968	target_os = "linux",
969	target_os = "cygwin",
970	target_os = "emscripten",
971	target_os = "android",
972	target_os = "solaris",
973	target_os = "illumos",
974	target_os = "haiku",
975	target_os = "l4re",
976	target_os = "fuchsia",
977	target_os = "redox",
978	target_os = "vxworks",
979	target_os = "espidf",
980	target_os = "horizon",
981	target_os = "vita",
982	target_os = "aix",
983	target_os = "nto",
984	target_os = "hurd",
985	target_os = "rtems",
986	target_vendor = "apple",
987	))]
988	pub fn ino(&self) -> u64 {
989	self.entry.d_ino as u64
990	}
991
992	#[cfg(any(
993	target_os = "freebsd",
994	target_os = "openbsd",
995	target_os = "netbsd",
996	target_os = "dragonfly"
997	))]
998	pub fn ino(&self) -> u64 {
999	self.entry.d_fileno as u64
1000	}
1001
1002	#[cfg(target_os = "nuttx")]
1003	pub fn ino(&self) -> u64 {
1004	// Leave this 0 for now, as NuttX does not provide an inode number
1005	// in its directory entries.
1006	`0`
1007	}
1008
1009	#[cfg(any(
1010	target_os = "netbsd",
1011	target_os = "openbsd",
1012	target_os = "freebsd",
1013	target_os = "dragonfly",
1014	target_vendor = "apple",
1015	))]
1016	fn name_bytes(&self) -> &[u8] {
1017	use crate::slice;
1018	unsafe {
1019	slice::from_raw_parts(
1020	self.entry.d_name.as_ptr() as *const u8,
1021	self.entry.d_namlen as usize,
1022	)
1023	}
1024	}
1025	#[cfg(not(any(
1026	target_os = "netbsd",
1027	target_os = "openbsd",
1028	target_os = "freebsd",
1029	target_os = "dragonfly",
1030	target_vendor = "apple",
1031	)))]
1032	fn name_bytes(&self) -> &[u8] {
1033	self.name_cstr().to_bytes()
1034	}
1035
1036	#[cfg(not(any(
1037	target_os = "android",
1038	target_os = "linux",
1039	target_os = "solaris",
1040	target_os = "illumos",
1041	target_os = "fuchsia",
1042	target_os = "redox",
1043	target_os = "aix",
1044	target_os = "nto",
1045	target_os = "vita",
1046	target_os = "hurd",
1047	)))]
1048	fn name_cstr(&self) -> &CStr {
1049	unsafe { CStr::from_ptr(self.entry.d_name.as_ptr()) }
1050	}
1051	#[cfg(any(
1052	target_os = "android",
1053	target_os = "linux",
1054	target_os = "solaris",
1055	target_os = "illumos",
1056	target_os = "fuchsia",
1057	target_os = "redox",
1058	target_os = "aix",
1059	target_os = "nto",
1060	target_os = "vita",
1061	target_os = "hurd",
1062	))]
1063	fn name_cstr(&self) -> &CStr {
1064	&self.name
1065	}
1066
1067	pub fn file_name_os_str(&self) -> &OsStr {
1068	OsStr::from_bytes(self.name_bytes())
1069	}
1070	}
1071
1072	impl OpenOptions {
1073	pub fn new() -> OpenOptions {
1074	OpenOptions {
1075	// generic
1076	read: `false`,
1077	write: `false`,
1078	append: `false`,
1079	truncate: `false`,
1080	create: `false`,
1081	create_new: `false`,
1082	// system-specific
1083	custom_flags: `0`,
1084	mode: `0o666`,
1085	}
1086	}
1087
1088	pub fn read(&mut self, read: bool) {
1089	self.read = read;
1090	}
1091	pub fn write(&mut self, write: bool) {
1092	self.write = write;
1093	}
1094	pub fn append(&mut self, append: bool) {
1095	self.append = append;
1096	}
1097	pub fn truncate(&mut self, truncate: bool) {
1098	self.truncate = truncate;
1099	}
1100	pub fn create(&mut self, create: bool) {
1101	self.create = create;
1102	}
1103	pub fn create_new(&mut self, create_new: bool) {
1104	self.create_new = create_new;
1105	}
1106
1107	pub fn custom_flags(&mut self, flags: i32) {
1108	self.custom_flags = flags;
1109	}
1110	pub fn mode(&mut self, mode: u32) {
1111	self.mode = mode as mode_t;
1112	}
1113
1114	fn get_access_mode(&self) -> io::Result<c_int> {
1115	match (self.read, self.write, self.append) {
1116	(`true`, `false`, `false`) => Ok(libc::O_RDONLY),
1117	(`false`, `true`, `false`) => Ok(libc::O_WRONLY),
1118	(`true`, `true`, `false`) => Ok(libc::O_RDWR),
1119	(`false`, _, `true`) => Ok(libc::O_WRONLY \| libc::O_APPEND),
1120	(`true`, _, `true`) => Ok(libc::O_RDWR \| libc::O_APPEND),
1121	(`false`, `false`, `false`) => Err(Error::from_raw_os_error(libc::EINVAL)),
1122	}
1123	}
1124
1125	fn get_creation_mode(&self) -> io::Result<c_int> {
1126	match (self.write, self.append) {
1127	(`true`, `false`) => {}
1128	(`false`, `false`) => {
1129	if self.truncate \|\| self.create \|\| self.create_new {
1130	return Err(Error::from_raw_os_error(libc::EINVAL));
1131	}
1132	}
1133	(_, `true`) => {
1134	if self.truncate && !self.create_new {
1135	return Err(Error::from_raw_os_error(libc::EINVAL));
1136	}
1137	}
1138	}
1139
1140	Ok(match (self.create, self.truncate, self.create_new) {
1141	(`false`, `false`, `false`) => `0`,
1142	(`true`, `false`, `false`) => libc::O_CREAT,
1143	(`false`, `true`, `false`) => libc::O_TRUNC,
1144	(`true`, `true`, `false`) => libc::O_CREAT \| libc::O_TRUNC,
1145	(_, _, `true`) => libc::O_CREAT \| libc::O_EXCL,
1146	})
1147	}
1148	}
1149
1150	impl fmt::Debug for OpenOptions {
1151	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1152	let OpenOptions { read: &bool, write: &bool, append: &bool, truncate: &bool, create: &bool, create_new: &bool, custom_flags: &i32, mode: &u32 } =
1153	self;
1154	f&mut DebugStruct<'_, '_>.debug_struct("OpenOptions")
1155	.field("read", read)
1156	.field("write", write)
1157	.field("append", append)
1158	.field("truncate", truncate)
1159	.field("create", create)
1160	.field("create_new", create_new)
1161	.field("custom_flags", custom_flags)
1162	.field(name:"mode", &Mode(*mode))
1163	.finish()
1164	}
1165	}
1166
1167	impl File {
1168	pub fn open(path: &Path, opts: &OpenOptions) -> io::Result<File> {
1169	run_path_with_cstr(path, &\|path\| File::open_c(path, opts))
1170	}
1171
1172	pub fn open_c(path: &CStr, opts: &OpenOptions) -> io::Result<File> {
1173	let flags = libc::O_CLOEXEC
1174	\| opts.get_access_mode()?
1175	\| opts.get_creation_mode()?
1176	\| (opts.custom_flags as c_int & !libc::O_ACCMODE);
1177	// The third argument of `open64` is documented to have type `mode_t`. On
1178	// some platforms (like macOS, where `open64` is actually `open`), `mode_t` is `u16`.
1179	// However, since this is a variadic function, C integer promotion rules mean that on
1180	// the ABI level, this still gets passed as `c_int` (aka `u32` on Unix platforms).
1181	let fd = cvt_r(\|\| unsafe { open64(path.as_ptr(), flags, opts.mode as c_int) })?;
1182	Ok(File(unsafe { FileDesc::from_raw_fd(fd) }))
1183	}
1184
1185	pub fn file_attr(&self) -> io::Result<FileAttr> {
1186	let fd = self.as_raw_fd();
1187
1188	cfg_has_statx! {
1189	if let Some(ret) = unsafe { try_statx(
1190	fd,
1191	c"".as_ptr() as *const c_char,
1192	libc::AT_EMPTY_PATH \| libc::AT_STATX_SYNC_AS_STAT,
1193	libc::STATX_BASIC_STATS \| libc::STATX_BTIME,
1194	) } {
1195	return ret;
1196	}
1197	}
1198
1199	let mut stat: stat64 = unsafe { mem::zeroed() };
1200	cvt(unsafe { fstat64(fd, &mut stat) })?;
1201	Ok(FileAttr::from_stat64(stat))
1202	}
1203
1204	pub fn fsync(&self) -> io::Result<()> {
1205	cvt_r(\|\| unsafe { os_fsync(self.as_raw_fd()) })?;
1206	return Ok(());
1207
1208	#[cfg(target_vendor = "apple")]
1209	unsafe fn os_fsync(fd: c_int) -> c_int {
1210	libc::fcntl(fd, libc::F_FULLFSYNC)
1211	}
1212	#[cfg(not(target_vendor = "apple"))]
1213	unsafe fn os_fsync(fd: c_int) -> c_int {
1214	libc::fsync(fd)
1215	}
1216	}
1217
1218	pub fn datasync(&self) -> io::Result<()> {
1219	cvt_r(\|\| unsafe { os_datasync(self.as_raw_fd()) })?;
1220	return Ok(());
1221
1222	#[cfg(target_vendor = "apple")]
1223	unsafe fn os_datasync(fd: c_int) -> c_int {
1224	libc::fcntl(fd, libc::F_FULLFSYNC)
1225	}
1226	#[cfg(any(
1227	target_os = "freebsd",
1228	target_os = "fuchsia",
1229	target_os = "linux",
1230	target_os = "cygwin",
1231	target_os = "android",
1232	target_os = "netbsd",
1233	target_os = "openbsd",
1234	target_os = "nto",
1235	target_os = "hurd",
1236	))]
1237	unsafe fn os_datasync(fd: c_int) -> c_int {
1238	libc::fdatasync(fd)
1239	}
1240	#[cfg(not(any(
1241	target_os = "android",
1242	target_os = "fuchsia",
1243	target_os = "freebsd",
1244	target_os = "linux",
1245	target_os = "cygwin",
1246	target_os = "netbsd",
1247	target_os = "openbsd",
1248	target_os = "nto",
1249	target_os = "hurd",
1250	target_vendor = "apple",
1251	)))]
1252	unsafe fn os_datasync(fd: c_int) -> c_int {
1253	libc::fsync(fd)
1254	}
1255	}
1256
1257	#[cfg(any(
1258	target_os = "freebsd",
1259	target_os = "fuchsia",
1260	target_os = "linux",
1261	target_os = "netbsd",
1262	target_vendor = "apple",
1263	))]
1264	pub fn lock(&self) -> io::Result<()> {
1265	cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_EX) })?;
1266	return Ok(());
1267	}
1268
1269	#[cfg(not(any(
1270	target_os = "freebsd",
1271	target_os = "fuchsia",
1272	target_os = "linux",
1273	target_os = "netbsd",
1274	target_vendor = "apple",
1275	)))]
1276	pub fn lock(&self) -> io::Result<()> {
1277	Err(io::const_error!(io::ErrorKind::Unsupported, "lock() not supported"))
1278	}
1279
1280	#[cfg(any(
1281	target_os = "freebsd",
1282	target_os = "fuchsia",
1283	target_os = "linux",
1284	target_os = "netbsd",
1285	target_vendor = "apple",
1286	))]
1287	pub fn lock_shared(&self) -> io::Result<()> {
1288	cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_SH) })?;
1289	return Ok(());
1290	}
1291
1292	#[cfg(not(any(
1293	target_os = "freebsd",
1294	target_os = "fuchsia",
1295	target_os = "linux",
1296	target_os = "netbsd",
1297	target_vendor = "apple",
1298	)))]
1299	pub fn lock_shared(&self) -> io::Result<()> {
1300	Err(io::const_error!(io::ErrorKind::Unsupported, "lock_shared() not supported"))
1301	}
1302
1303	#[cfg(any(
1304	target_os = "freebsd",
1305	target_os = "fuchsia",
1306	target_os = "linux",
1307	target_os = "netbsd",
1308	target_vendor = "apple",
1309	))]
1310	pub fn try_lock(&self) -> io::Result<bool> {
1311	let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_EX \| libc::LOCK_NB) });
1312	if let Err(ref err) = result {
1313	if err.kind() == io::ErrorKind::WouldBlock {
1314	return Ok(`false`);
1315	}
1316	}
1317	result?;
1318	return Ok(`true`);
1319	}
1320
1321	#[cfg(not(any(
1322	target_os = "freebsd",
1323	target_os = "fuchsia",
1324	target_os = "linux",
1325	target_os = "netbsd",
1326	target_vendor = "apple",
1327	)))]
1328	pub fn try_lock(&self) -> io::Result<bool> {
1329	Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock() not supported"))
1330	}
1331
1332	#[cfg(any(
1333	target_os = "freebsd",
1334	target_os = "fuchsia",
1335	target_os = "linux",
1336	target_os = "netbsd",
1337	target_vendor = "apple",
1338	))]
1339	pub fn try_lock_shared(&self) -> io::Result<bool> {
1340	let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_SH \| libc::LOCK_NB) });
1341	if let Err(ref err) = result {
1342	if err.kind() == io::ErrorKind::WouldBlock {
1343	return Ok(`false`);
1344	}
1345	}
1346	result?;
1347	return Ok(`true`);
1348	}
1349
1350	#[cfg(not(any(
1351	target_os = "freebsd",
1352	target_os = "fuchsia",
1353	target_os = "linux",
1354	target_os = "netbsd",
1355	target_vendor = "apple",
1356	)))]
1357	pub fn try_lock_shared(&self) -> io::Result<bool> {
1358	Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock_shared() not supported"))
1359	}
1360
1361	#[cfg(any(
1362	target_os = "freebsd",
1363	target_os = "fuchsia",
1364	target_os = "linux",
1365	target_os = "netbsd",
1366	target_vendor = "apple",
1367	))]
1368	pub fn unlock(&self) -> io::Result<()> {
1369	cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_UN) })?;
1370	return Ok(());
1371	}
1372
1373	#[cfg(not(any(
1374	target_os = "freebsd",
1375	target_os = "fuchsia",
1376	target_os = "linux",
1377	target_os = "netbsd",
1378	target_vendor = "apple",
1379	)))]
1380	pub fn unlock(&self) -> io::Result<()> {
1381	Err(io::const_error!(io::ErrorKind::Unsupported, "unlock() not supported"))
1382	}
1383
1384	pub fn truncate(&self, size: u64) -> io::Result<()> {
1385	let size: off64_t =
1386	size.try_into().map_err(\|e\| io::Error::new(io::ErrorKind::InvalidInput, e))?;
1387	cvt_r(\|\| unsafe { ftruncate64(self.as_raw_fd(), size) }).map(drop)
1388	}
1389
1390	pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
1391	self.0.read(buf)
1392	}
1393
1394	pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
1395	self.0.read_vectored(bufs)
1396	}
1397
1398	#[inline]
1399	pub fn is_read_vectored(&self) -> bool {
1400	self.0.is_read_vectored()
1401	}
1402
1403	pub fn read_at(&self, buf: &mut [u8], offset: u64) -> io::Result<usize> {
1404	self.0.read_at(buf, offset)
1405	}
1406
1407	pub fn read_buf(&self, cursor: BorrowedCursor<'_>) -> io::Result<()> {
1408	self.0.read_buf(cursor)
1409	}
1410
1411	pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
1412	self.0.read_vectored_at(bufs, offset)
1413	}
1414
1415	pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
1416	self.0.write(buf)
1417	}
1418
1419	pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
1420	self.0.write_vectored(bufs)
1421	}
1422
1423	#[inline]
1424	pub fn is_write_vectored(&self) -> bool {
1425	self.0.is_write_vectored()
1426	}
1427
1428	pub fn write_at(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
1429	self.0.write_at(buf, offset)
1430	}
1431
1432	pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
1433	self.0.write_vectored_at(bufs, offset)
1434	}
1435
1436	#[inline]
1437	pub fn flush(&self) -> io::Result<()> {
1438	Ok(())
1439	}
1440
1441	pub fn seek(&self, pos: SeekFrom) -> io::Result<u64> {
1442	let (whence, pos) = match pos {
1443	// Casting to `i64` is fine, too large values will end up as
1444	// negative which will cause an error in `lseek64`.
1445	SeekFrom::Start(off) => (libc::SEEK_SET, off as i64),
1446	SeekFrom::End(off) => (libc::SEEK_END, off),
1447	SeekFrom::Current(off) => (libc::SEEK_CUR, off),
1448	};
1449	let n = cvt(unsafe { lseek64(self.as_raw_fd(), pos as off64_t, whence) })?;
1450	Ok(n as u64)
1451	}
1452
1453	pub fn tell(&self) -> io::Result<u64> {
1454	self.seek(SeekFrom::Current(`0`))
1455	}
1456
1457	pub fn duplicate(&self) -> io::Result<File> {
1458	self.0.duplicate().map(File)
1459	}
1460
1461	pub fn set_permissions(&self, perm: FilePermissions) -> io::Result<()> {
1462	cvt_r(\|\| unsafe { libc::fchmod(self.as_raw_fd(), perm.mode) })?;
1463	Ok(())
1464	}
1465
1466	// FIXME(#115199): Rust currently omits weak function definitions
1467	// and its metadata from LLVM IR.
1468	#[cfg_attr(
1469	any(
1470	target_os = "android",
1471	all(
1472	target_os = "linux",
1473	target_env = "gnu",
1474	target_pointer_width = "32",
1475	not(target_arch = "riscv32")
1476	)
1477	),
1478	no_sanitize(cfi)
1479	)]
1480	pub fn set_times(&self, times: FileTimes) -> io::Result<()> {
1481	#[cfg(not(any(
1482	target_os = "redox",
1483	target_os = "espidf",
1484	target_os = "horizon",
1485	target_os = "vxworks",
1486	target_os = "nuttx",
1487	)))]
1488	let to_timespec = \|time: Option<SystemTime>\| match time {
1489	Some(time) if let Some(ts) = time.t.to_timespec() => Ok(ts),
1490	Some(time) if time > crate::sys::time::UNIX_EPOCH => Err(io::const_error!(
1491	io::ErrorKind::InvalidInput,
1492	"timestamp is too large to set as a file time",
1493	)),
1494	Some(_) => Err(io::const_error!(
1495	io::ErrorKind::InvalidInput,
1496	"timestamp is too small to set as a file time",
1497	)),
1498	None => Ok(libc::timespec { tv_sec: `0`, tv_nsec: libc::UTIME_OMIT as _ }),
1499	};
1500	cfg_if::cfg_if! {
1501	if #[cfg(any(target_os = "redox", target_os = "espidf", target_os = "horizon", target_os = "vxworks", target_os = "nuttx"))] {
1502	// Redox doesn't appear to support `UTIME_OMIT`.
1503	// ESP-IDF and HorizonOS do not support `futimens` at all and the behavior for those OS is therefore
1504	// the same as for Redox.
1505	// `futimens` and `UTIME_OMIT` are a work in progress for vxworks.
1506	let _ = times;
1507	Err(io::const_error!(
1508	io::ErrorKind::Unsupported,
1509	"setting file times not supported",
1510	))
1511	} else if #[cfg(target_vendor = "apple")] {
1512	let mut buf = [mem::MaybeUninit::<libc::timespec>::uninit(); `3`];
1513	let mut num_times = `0`;
1514	let mut attrlist: libc::attrlist = unsafe { mem::zeroed() };
1515	attrlist.bitmapcount = libc::ATTR_BIT_MAP_COUNT;
1516	if times.created.is_some() {
1517	buf[num_times].write(to_timespec(times.created)?);
1518	num_times += `1`;
1519	attrlist.commonattr \|= libc::ATTR_CMN_CRTIME;
1520	}
1521	if times.modified.is_some() {
1522	buf[num_times].write(to_timespec(times.modified)?);
1523	num_times += `1`;
1524	attrlist.commonattr \|= libc::ATTR_CMN_MODTIME;
1525	}
1526	if times.accessed.is_some() {
1527	buf[num_times].write(to_timespec(times.accessed)?);
1528	num_times += `1`;
1529	attrlist.commonattr \|= libc::ATTR_CMN_ACCTIME;
1530	}
1531	cvt(unsafe { libc::fsetattrlist(
1532	self.as_raw_fd(),
1533	(&raw const attrlist).cast::<libc::c_void>().cast_mut(),
1534	buf.as_ptr().cast::<libc::c_void>().cast_mut(),
1535	num_times * size_of::<libc::timespec>(),
1536	`0`
1537	) })?;
1538	Ok(())
1539	} else if #[cfg(target_os = "android")] {
1540	let times = [to_timespec(times.accessed)?, to_timespec(times.modified)?];
1541	// futimens requires Android API level 19
1542	cvt(unsafe {
1543	weak!(fn futimens(c_int, *const libc::timespec) -> c_int);
1544	match futimens.get() {
1545	Some(futimens) => futimens(self.as_raw_fd(), times.as_ptr()),
1546	None => return Err(io::const_error!(
1547	io::ErrorKind::Unsupported,
1548	"setting file times requires Android API level >= 19",
1549	)),
1550	}
1551	})?;
1552	Ok(())
1553	} else {
1554	#[cfg(all(target_os = "linux", target_env = "gnu", target_pointer_width = "32", not(target_arch = "riscv32")))]
1555	{
1556	use crate::sys::{time::__timespec64, weak::weak};
1557
1558	// Added in glibc 2.34
1559	weak!(fn __futimens64(libc::c_int, *const __timespec64) -> libc::c_int);
1560
1561	if let Some(futimens64) = __futimens64.get() {
1562	let to_timespec = \|time: Option<SystemTime>\| time.map(\|time\| time.t.to_timespec64())
1563	.unwrap_or(__timespec64::new(`0`, libc::UTIME_OMIT as _));
1564	let times = [to_timespec(times.accessed), to_timespec(times.modified)];
1565	cvt(unsafe { futimens64(self.as_raw_fd(), times.as_ptr()) })?;
1566	return Ok(());
1567	}
1568	}
1569	let times = [to_timespec(times.accessed)?, to_timespec(times.modified)?];
1570	cvt(unsafe { libc::futimens(self.as_raw_fd(), times.as_ptr()) })?;
1571	Ok(())
1572	}
1573	}
1574	}
1575	}
1576
1577	impl DirBuilder {
1578	pub fn new() -> DirBuilder {
1579	DirBuilder { mode: `0o777` }
1580	}
1581
1582	pub fn mkdir(&self, p: &Path) -> io::Result<()> {
1583	run_path_with_cstr(path:p, &\|p: &CStr\| cvt(unsafe { libc::mkdir(p.as_ptr(), self.mode) }).map(\|_\| ()))
1584	}
1585
1586	pub fn set_mode(&mut self, mode: u32) {
1587	self.mode = mode as mode_t;
1588	}
1589	}
1590
1591	impl fmt::Debug for DirBuilder {
1592	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1593	let DirBuilder { mode: &u32 } = self;
1594	f.debug_struct("DirBuilder").field(name:"mode", &Mode(*mode)).finish()
1595	}
1596	}
1597
1598	impl AsInner<FileDesc> for File {
1599	#[inline]
1600	fn as_inner(&self) -> &FileDesc {
1601	&self.0
1602	}
1603	}
1604
1605	impl AsInnerMut<FileDesc> for File {
1606	#[inline]
1607	fn as_inner_mut(&mut self) -> &mut FileDesc {
1608	&mut self.0
1609	}
1610	}
1611
1612	impl IntoInner<FileDesc> for File {
1613	fn into_inner(self) -> FileDesc {
1614	self.0
1615	}
1616	}
1617
1618	impl FromInner<FileDesc> for File {
1619	fn from_inner(file_desc: FileDesc) -> Self {
1620	Self(file_desc)
1621	}
1622	}
1623
1624	impl AsFd for File {
1625	#[inline]
1626	fn as_fd(&self) -> BorrowedFd<'_> {
1627	self.0.as_fd()
1628	}
1629	}
1630
1631	impl AsRawFd for File {
1632	#[inline]
1633	fn as_raw_fd(&self) -> RawFd {
1634	self.0.as_raw_fd()
1635	}
1636	}
1637
1638	impl IntoRawFd for File {
1639	fn into_raw_fd(self) -> RawFd {
1640	self.0.into_raw_fd()
1641	}
1642	}
1643
1644	impl FromRawFd for File {
1645	unsafe fn from_raw_fd(raw_fd: RawFd) -> Self {
1646	Self(FromRawFd::from_raw_fd(raw_fd))
1647	}
1648	}
1649
1650	impl fmt::Debug for File {
1651	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1652	#[cfg(any(target_os = "linux", target_os = "illumos", target_os = "solaris"))]
1653	fn get_path(fd: c_int) -> Option<PathBuf> {
1654	let mut p = PathBuf::from("/proc/self/fd");
1655	p.push(&fd.to_string());
1656	readlink(&p).ok()
1657	}
1658
1659	#[cfg(any(target_vendor = "apple", target_os = "netbsd"))]
1660	fn get_path(fd: c_int) -> Option<PathBuf> {
1661	// FIXME: The use of PATH_MAX is generally not encouraged, but it
1662	// is inevitable in this case because Apple targets and NetBSD define `fcntl`
1663	// with `F_GETPATH` in terms of `MAXPATHLEN`, and there are no
1664	// alternatives. If a better method is invented, it should be used
1665	// instead.
1666	let mut buf = vec![`0`; libc::PATH_MAX as usize];
1667	let n = unsafe { libc::fcntl(fd, libc::F_GETPATH, buf.as_ptr()) };
1668	if n == `-1` {
1669	cfg_if::cfg_if! {
1670	if #[cfg(target_os = "netbsd")] {
1671	// fallback to procfs as last resort
1672	let mut p = PathBuf::from("/proc/self/fd");
1673	p.push(&fd.to_string());
1674	return readlink(&p).ok();
1675	} else {
1676	return None;
1677	}
1678	}
1679	}
1680	let l = buf.iter().position(\|&c\| c == `0`).unwrap();
1681	buf.truncate(l as usize);
1682	buf.shrink_to_fit();
1683	Some(PathBuf::from(OsString::from_vec(buf)))
1684	}
1685
1686	#[cfg(target_os = "freebsd")]
1687	fn get_path(fd: c_int) -> Option<PathBuf> {
1688	let info = Box::<libc::kinfo_file>::new_zeroed();
1689	let mut info = unsafe { info.assume_init() };
1690	info.kf_structsize = size_of::<libc::kinfo_file>() as libc::c_int;
1691	let n = unsafe { libc::fcntl(fd, libc::F_KINFO, &mut *info) };
1692	if n == `-1` {
1693	return None;
1694	}
1695	let buf = unsafe { CStr::from_ptr(info.kf_path.as_mut_ptr()).to_bytes().to_vec() };
1696	Some(PathBuf::from(OsString::from_vec(buf)))
1697	}
1698
1699	#[cfg(target_os = "vxworks")]
1700	fn get_path(fd: c_int) -> Option<PathBuf> {
1701	let mut buf = vec![`0`; libc::PATH_MAX as usize];
1702	let n = unsafe { libc::ioctl(fd, libc::FIOGETNAME, buf.as_ptr()) };
1703	if n == `-1` {
1704	return None;
1705	}
1706	let l = buf.iter().position(\|&c\| c == `0`).unwrap();
1707	buf.truncate(l as usize);
1708	Some(PathBuf::from(OsString::from_vec(buf)))
1709	}
1710
1711	#[cfg(not(any(
1712	target_os = "linux",
1713	target_os = "vxworks",
1714	target_os = "freebsd",
1715	target_os = "netbsd",
1716	target_os = "illumos",
1717	target_os = "solaris",
1718	target_vendor = "apple",
1719	)))]
1720	fn get_path(_fd: c_int) -> Option<PathBuf> {
1721	// FIXME(#24570): implement this for other Unix platforms
1722	None
1723	}
1724
1725	fn get_mode(fd: c_int) -> Option<(bool, bool)> {
1726	let mode = unsafe { libc::fcntl(fd, libc::F_GETFL) };
1727	if mode == `-1` {
1728	return None;
1729	}
1730	match mode & libc::O_ACCMODE {
1731	libc::O_RDONLY => Some((`true`, `false`)),
1732	libc::O_RDWR => Some((`true`, `true`)),
1733	libc::O_WRONLY => Some((`false`, `true`)),
1734	_ => None,
1735	}
1736	}
1737
1738	let fd = self.as_raw_fd();
1739	let mut b = f.debug_struct("File");
1740	b.field("fd", &fd);
1741	if let Some(path) = get_path(fd) {
1742	b.field("path", &path);
1743	}
1744	if let Some((read, write)) = get_mode(fd) {
1745	b.field("read", &read).field("write", &write);
1746	}
1747	b.finish()
1748	}
1749	}
1750
1751	// Format in octal, followed by the mode format used in `ls -l`.
1752	//
1753	// References:
1754	// https://pubs.opengroup.org/onlinepubs/009696899/utilities/ls.html
1755	// https://www.gnu.org/software/libc/manual/html_node/Testing-File-Type.html
1756	// https://www.gnu.org/software/libc/manual/html_node/Permission-Bits.html
1757	//
1758	// Example:
1759	// 0o100664 (-rw-rw-r--)
1760	impl fmt::Debug for Mode {
1761	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1762	let Self(mode) = *self;
1763	write!(f, "0o{mode:`06`o}")?;
1764
1765	let entry_type = match mode & libc::S_IFMT {
1766	libc::S_IFDIR => 'd',
1767	libc::S_IFBLK => 'b',
1768	libc::S_IFCHR => 'c',
1769	libc::S_IFLNK => 'l',
1770	libc::S_IFIFO => 'p',
1771	libc::S_IFREG => '-',
1772	_ => return Ok(()),
1773	};
1774
1775	f.write_str(" (")?;
1776	f.write_char(entry_type)?;
1777
1778	// Owner permissions
1779	f.write_char(if mode & libc::S_IRUSR != `0` { 'r' } else { '-' })?;
1780	f.write_char(if mode & libc::S_IWUSR != `0` { 'w' } else { '-' })?;
1781	let owner_executable = mode & libc::S_IXUSR != `0`;
1782	let setuid = mode as c_int & libc::S_ISUID as c_int != `0`;
1783	f.write_char(match (owner_executable, setuid) {
1784	(`true`, `true`) => 's', // executable and setuid
1785	(`false`, `true`) => 'S', // setuid
1786	(`true`, `false`) => 'x', // executable
1787	(`false`, `false`) => '-',
1788	})?;
1789
1790	// Group permissions
1791	f.write_char(if mode & libc::S_IRGRP != `0` { 'r' } else { '-' })?;
1792	f.write_char(if mode & libc::S_IWGRP != `0` { 'w' } else { '-' })?;
1793	let group_executable = mode & libc::S_IXGRP != `0`;
1794	let setgid = mode as c_int & libc::S_ISGID as c_int != `0`;
1795	f.write_char(match (group_executable, setgid) {
1796	(`true`, `true`) => 's', // executable and setgid
1797	(`false`, `true`) => 'S', // setgid
1798	(`true`, `false`) => 'x', // executable
1799	(`false`, `false`) => '-',
1800	})?;
1801
1802	// Other permissions
1803	f.write_char(if mode & libc::S_IROTH != `0` { 'r' } else { '-' })?;
1804	f.write_char(if mode & libc::S_IWOTH != `0` { 'w' } else { '-' })?;
1805	let other_executable = mode & libc::S_IXOTH != `0`;
1806	let sticky = mode as c_int & libc::S_ISVTX as c_int != `0`;
1807	f.write_char(match (entry_type, other_executable, sticky) {
1808	('d', `true`, `true`) => 't', // searchable and restricted deletion
1809	('d', `false`, `true`) => 'T', // restricted deletion
1810	(_, `true`, _) => 'x', // executable
1811	(_, `false`, _) => '-',
1812	})?;
1813
1814	f.write_char(')')
1815	}
1816	}
1817
1818	pub fn readdir(path: &Path) -> io::Result<ReadDir> {
1819	let ptr: mut DIR = run_path_with_cstr(path, &\|p: &CStr\| unsafe* { Ok(libc::opendir(dirname:p.as_ptr())) })?;
1820	if ptr.is_null() {
1821	Err(Error::last_os_error())
1822	} else {
1823	let root: PathBuf = path.to_path_buf();
1824	let inner: InnerReadDir = InnerReadDir { dirp: Dir(ptr), root };
1825	Ok(ReadDir::new(inner))
1826	}
1827	}
1828
1829	pub fn unlink(p: &Path) -> io::Result<()> {
1830	run_path_with_cstr(path:p, &\|p: &CStr\| cvt(unsafe { libc::unlink(p.as_ptr()) }).map(\|_\| ()))
1831	}
1832
1833	pub fn rename(old: &Path, new: &Path) -> io::Result<()> {
1834	run_path_with_cstr(path:old, &\|old: &CStr\| {
1835	run_path_with_cstr(path:new, &\|new: &CStr\| {
1836	cvt(unsafe { libc::rename(old.as_ptr(), new.as_ptr()) }).map(\|_\| ())
1837	})
1838	})
1839	}
1840
1841	pub fn set_perm(p: &Path, perm: FilePermissions) -> io::Result<()> {
1842	run_path_with_cstr(path:p, &\|p: &CStr\| cvt_r(\|\| unsafe { libc::chmod(p.as_ptr(), perm.mode) }).map(\|_\| ()))
1843	}
1844
1845	pub fn rmdir(p: &Path) -> io::Result<()> {
1846	run_path_with_cstr(path:p, &\|p: &CStr\| cvt(unsafe { libc::rmdir(p.as_ptr()) }).map(\|_\| ()))
1847	}
1848
1849	pub fn readlink(p: &Path) -> io::Result<PathBuf> {
1850	run_path_with_cstr(p, &\|c_path\| {
1851	let p = c_path.as_ptr();
1852
1853	let mut buf = Vec::with_capacity(`256`);
1854
1855	loop {
1856	let buf_read =
1857	cvt(unsafe { libc::readlink(p, buf.as_mut_ptr() as *mut _, buf.capacity()) })?
1858	as usize;
1859
1860	unsafe {
1861	buf.set_len(buf_read);
1862	}
1863
1864	if buf_read != buf.capacity() {
1865	buf.shrink_to_fit();
1866
1867	return Ok(PathBuf::from(OsString::from_vec(buf)));
1868	}
1869
1870	// Trigger the internal buffer resizing logic of `Vec` by requiring
1871	// more space than the current capacity. The length is guaranteed to be
1872	// the same as the capacity due to the if statement above.
1873	buf.reserve(`1`);
1874	}
1875	})
1876	}
1877
1878	pub fn symlink(original: &Path, link: &Path) -> io::Result<()> {
1879	run_path_with_cstr(path:original, &\|original: &CStr\| {
1880	run_path_with_cstr(path:link, &\|link: &CStr\| {
1881	cvt(unsafe { libc::symlink(original.as_ptr(), link.as_ptr()) }).map(\|_\| ())
1882	})
1883	})
1884	}
1885
1886	pub fn link(original: &Path, link: &Path) -> io::Result<()> {
1887	run_path_with_cstr(path:original, &\|original: &CStr\| {
1888	run_path_with_cstr(path:link, &\|link: &CStr\| {
1889	cfg_if::cfg_if! {
1890	if #[cfg(any(target_os = "vxworks", target_os = "redox", target_os = "android", target_os = "espidf", target_os = "horizon", target_os = "vita", target_env = "nto70"))] {
1891	// VxWorks, Redox and ESP-IDF lack `linkat`, so use `link` instead. POSIX leaves
1892	// it implementation-defined whether `link` follows symlinks, so rely on the
1893	// `symlink_hard_link` test in library/std/src/fs/tests.rs to check the behavior.
1894	// Android has `linkat` on newer versions, but we happen to know `link`
1895	// always has the correct behavior, so it's here as well.
1896	cvt(unsafe { libc::link(original.as_ptr(), link.as_ptr()) })?;
1897	} else {
1898	// Where we can, use `linkat` instead of `link`; see the comment above
1899	// this one for details on why.
1900	cvt(unsafe { libc::linkat(libc::AT_FDCWD, original.as_ptr(), libc::AT_FDCWD, link.as_ptr(), `0`) })?;
1901	}
1902	}
1903	Ok(())
1904	})
1905	})
1906	}
1907
1908	pub fn stat(p: &Path) -> io::Result<FileAttr> {
1909	run_path_with_cstr(path:p, &\|p: &CStr\| {
1910	cfg_has_statx! {
1911	if let Some(ret) = unsafe { try_statx(
1912	libc::AT_FDCWD,
1913	p.as_ptr(),
1914	libc::AT_STATX_SYNC_AS_STAT,
1915	libc::STATX_BASIC_STATS \| libc::STATX_BTIME,
1916	) } {
1917	return ret;
1918	}
1919	}
1920
1921	let mut stat: stat64 = unsafe { mem::zeroed() };
1922	cvt(unsafe { stat64(path:p.as_ptr(), &mut stat) })?;
1923	Ok(FileAttr::from_stat64(stat))
1924	})
1925	}
1926
1927	pub fn lstat(p: &Path) -> io::Result<FileAttr> {
1928	run_path_with_cstr(path:p, &\|p: &CStr\| {
1929	cfg_has_statx! {
1930	if let Some(ret) = unsafe { try_statx(
1931	libc::AT_FDCWD,
1932	p.as_ptr(),
1933	libc::AT_SYMLINK_NOFOLLOW \| libc::AT_STATX_SYNC_AS_STAT,
1934	libc::STATX_BASIC_STATS \| libc::STATX_BTIME,
1935	) } {
1936	return ret;
1937	}
1938	}
1939
1940	let mut stat: stat64 = unsafe { mem::zeroed() };
1941	cvt(unsafe { lstat64(path:p.as_ptr(), &mut stat) })?;
1942	Ok(FileAttr::from_stat64(stat))
1943	})
1944	}
1945
1946	pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
1947	let r: mut i8 = run_path_with_cstr(path:p, &\|path: &CStr\| unsafe* {
1948	Ok(libc::realpath(pathname:path.as_ptr(), resolved:ptr::null_mut()))
1949	})?;
1950	if r.is_null() {
1951	return Err(io::Error::last_os_error());
1952	}
1953	Ok(PathBuf::from(OsString::from_vec(unsafe {
1954	let buf: Vec = CStr::from_ptr(r).to_bytes().to_vec();
1955	libc::free(r as *mut _);
1956	buf
1957	})))
1958	}
1959
1960	fn open_from(from: &Path) -> io::Result<(crate::fs::File, crate::fs::Metadata)> {
1961	use crate::fs::File;
1962	use crate::sys::fs::common::NOT_FILE_ERROR;
1963
1964	let reader: File = File::open(path:from)?;
1965	let metadata: Metadata = reader.metadata()?;
1966	if !metadata.is_file() {
1967	return Err(NOT_FILE_ERROR);
1968	}
1969	Ok((reader, metadata))
1970	}
1971
1972	#[cfg(target_os = "espidf")]
1973	fn open_to_and_set_permissions(
1974	to: &Path,
1975	_reader_metadata: &crate::fs::Metadata,
1976	) -> io::Result<(crate::fs::File, crate::fs::Metadata)> {
1977	use crate::fs::OpenOptions;
1978	let writer = OpenOptions::new().open(to)?;
1979	let writer_metadata = writer.metadata()?;
1980	Ok((writer, writer_metadata))
1981	}
1982
1983	#[cfg(not(target_os = "espidf"))]
1984	fn open_to_and_set_permissions(
1985	to: &Path,
1986	reader_metadata: &crate::fs::Metadata,
1987	) -> io::Result<(crate::fs::File, crate::fs::Metadata)> {
1988	use crate::fs::OpenOptions;
1989	use crate::os::unix::fs::{OpenOptionsExt, PermissionsExt};
1990
1991	let perm: Permissions = reader_metadata.permissions();
1992	let writer: File = OpenOptions::new()
1993	// create the file with the correct mode right away
1994	.mode(perm.mode())
1995	.write(`true`)
1996	.create(`true`)
1997	.truncate(`true`)
1998	.open(path:to)?;
1999	let writer_metadata: Metadata = writer.metadata()?;
2000	// fchmod is broken on vita
2001	#[cfg(not(target_os = "vita"))]
2002	if writer_metadata.is_file() {
2003	// Set the correct file permissions, in case the file already existed.
2004	// Don't set the permissions on already existing non-files like
2005	// pipes/FIFOs or device nodes.
2006	writer.set_permissions(perm)?;
2007	}
2008	Ok((writer, writer_metadata))
2009	}
2010
2011	mod cfm {
2012	use crate::fs::{File, Metadata};
2013	use crate::io::{BorrowedCursor, IoSlice, IoSliceMut, Read, Result, Write};
2014
2015	#[allow(dead_code)]
2016	pub struct CachedFileMetadata(pub File, pub Metadata);
2017
2018	impl Read for CachedFileMetadata {
2019	fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
2020	self.0.read(buf)
2021	}
2022	fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize> {
2023	self.0.read_vectored(bufs)
2024	}
2025	fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<()> {
2026	self.0.read_buf(cursor)
2027	}
2028	#[inline]
2029	fn is_read_vectored(&self) -> bool {
2030	self.0.is_read_vectored()
2031	}
2032	fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize> {
2033	self.0.read_to_end(buf)
2034	}
2035	fn read_to_string(&mut self, buf: &mut String) -> Result<usize> {
2036	self.0.read_to_string(buf)
2037	}
2038	}
2039	impl Write for CachedFileMetadata {
2040	fn write(&mut self, buf: &[u8]) -> Result<usize> {
2041	self.0.write(buf)
2042	}
2043	fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize> {
2044	self.0.write_vectored(bufs)
2045	}
2046	#[inline]
2047	fn is_write_vectored(&self) -> bool {
2048	self.0.is_write_vectored()
2049	}
2050	#[inline]
2051	fn flush(&mut self) -> Result<()> {
2052	self.0.flush()
2053	}
2054	}
2055	}
2056	#[cfg(any(target_os = "linux", target_os = "android"))]
2057	pub(crate) use cfm::CachedFileMetadata;
2058
2059	#[cfg(not(target_vendor = "apple"))]
2060	pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
2061	let (reader: File, reader_metadata: Metadata) = open_from(from)?;
2062	let (writer: File, writer_metadata: Metadata) = open_to_and_set_permissions(to, &reader_metadata)?;
2063
2064	io::copy(
2065	&mut cfm::CachedFileMetadata(reader, reader_metadata),
2066	&mut cfm::CachedFileMetadata(writer, writer_metadata),
2067	)
2068	}
2069
2070	#[cfg(target_vendor = "apple")]
2071	pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
2072	const COPYFILE_ALL: libc::copyfile_flags_t = libc::COPYFILE_METADATA \| libc::COPYFILE_DATA;
2073
2074	struct FreeOnDrop(libc::copyfile_state_t);
2075	impl Drop for FreeOnDrop {
2076	fn drop(&mut self) {
2077	// The code below ensures that `FreeOnDrop` is never a null pointer
2078	unsafe {
2079	// `copyfile_state_free` returns -1 if the `to` or `from` files
2080	// cannot be closed. However, this is not considered an error.
2081	libc::copyfile_state_free(self.0);
2082	}
2083	}
2084	}
2085
2086	let (reader, reader_metadata) = open_from(from)?;
2087
2088	let clonefile_result = run_path_with_cstr(to, &\|to\| {
2089	cvt(unsafe { libc::fclonefileat(reader.as_raw_fd(), libc::AT_FDCWD, to.as_ptr(), `0`) })
2090	});
2091	match clonefile_result {
2092	Ok(_) => return Ok(reader_metadata.len()),
2093	Err(e) => match e.raw_os_error() {
2094	// `fclonefileat` will fail on non-APFS volumes, if the
2095	// destination already exists, or if the source and destination
2096	// are on different devices. In all these cases `fcopyfile`
2097	// should succeed.
2098	Some(libc::ENOTSUP) \| Some(libc::EEXIST) \| Some(libc::EXDEV) => (),
2099	_ => return Err(e),
2100	},
2101	}
2102
2103	// Fall back to using `fcopyfile` if `fclonefileat` does not succeed.
2104	let (writer, writer_metadata) = open_to_and_set_permissions(to, &reader_metadata)?;
2105
2106	// We ensure that `FreeOnDrop` never contains a null pointer so it is
2107	// always safe to call `copyfile_state_free`
2108	let state = unsafe {
2109	let state = libc::copyfile_state_alloc();
2110	if state.is_null() {
2111	return Err(crate::io::Error::last_os_error());
2112	}
2113	FreeOnDrop(state)
2114	};
2115
2116	let flags = if writer_metadata.is_file() { COPYFILE_ALL } else { libc::COPYFILE_DATA };
2117
2118	cvt(unsafe { libc::fcopyfile(reader.as_raw_fd(), writer.as_raw_fd(), state.0, flags) })?;
2119
2120	let mut bytes_copied: libc::off_t = `0`;
2121	cvt(unsafe {
2122	libc::copyfile_state_get(
2123	state.0,
2124	libc::COPYFILE_STATE_COPIED as u32,
2125	(&raw mut bytes_copied) as *mut libc::c_void,
2126	)
2127	})?;
2128	Ok(bytes_copied as u64)
2129	}
2130
2131	pub fn chown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
2132	run_path_with_cstr(path, &\|path: &CStr\| {
2133	cvt(unsafe { libc::chown(path.as_ptr(), uid as libc::uid_t, gid as libc::gid_t) })
2134	.map(\|_\| ())
2135	})
2136	}
2137
2138	pub fn fchown(fd: c_int, uid: u32, gid: u32) -> io::Result<()> {
2139	cvt(unsafe { libc::fchown(fd, owner:uid as libc::uid_t, group:gid as libc::gid_t) })?;
2140	Ok(())
2141	}
2142
2143	#[cfg(not(target_os = "vxworks"))]
2144	pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
2145	run_path_with_cstr(path, &\|path: &CStr\| {
2146	cvt(unsafe { libc::lchown(path.as_ptr(), uid as libc::uid_t, gid as libc::gid_t) })
2147	.map(\|_\| ())
2148	})
2149	}
2150
2151	#[cfg(target_os = "vxworks")]
2152	pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
2153	let (_, _, _) = (path, uid, gid);
2154	Err(io::const_error!(io::ErrorKind::Unsupported, "lchown not supported by vxworks"))
2155	}
2156
2157	#[cfg(not(any(target_os = "fuchsia", target_os = "vxworks")))]
2158	pub fn chroot(dir: &Path) -> io::Result<()> {
2159	run_path_with_cstr(path:dir, &\|dir: &CStr\| cvt(unsafe { libc::chroot(dir.as_ptr()) }).map(\|_\| ()))
2160	}
2161
2162	#[cfg(target_os = "vxworks")]
2163	pub fn chroot(dir: &Path) -> io::Result<()> {
2164	let _ = dir;
2165	Err(io::const_error!(io::ErrorKind::Unsupported, "chroot not supported by vxworks"))
2166	}
2167
2168	pub use remove_dir_impl::remove_dir_all;
2169
2170	// Fallback for REDOX, ESP-ID, Horizon, Vita, Vxworks and Miri
2171	#[cfg(any(
2172	target_os = "redox",
2173	target_os = "espidf",
2174	target_os = "horizon",
2175	target_os = "vita",
2176	target_os = "nto",
2177	target_os = "vxworks",
2178	miri
2179	))]
2180	mod remove_dir_impl {
2181	pub use crate::sys::fs::common::remove_dir_all;
2182	}
2183
2184	// Modern implementation using openat(), unlinkat() and fdopendir()
2185	#[cfg(not(any(
2186	target_os = "redox",
2187	target_os = "espidf",
2188	target_os = "horizon",
2189	target_os = "vita",
2190	target_os = "nto",
2191	target_os = "vxworks",
2192	miri
2193	)))]
2194	mod remove_dir_impl {
2195	#[cfg(not(all(target_os = "linux", target_env = "gnu")))]
2196	use libc::{fdopendir, openat, unlinkat};
2197	#[cfg(all(target_os = "linux", target_env = "gnu"))]
2198	use libc::{fdopendir, openat64 as openat, unlinkat};
2199
2200	use super::{Dir, DirEntry, InnerReadDir, ReadDir, lstat};
2201	use crate::ffi::CStr;
2202	use crate::io;
2203	use crate::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd};
2204	use crate::os::unix::prelude::{OwnedFd, RawFd};
2205	use crate::path::{Path, PathBuf};
2206	use crate::sys::common::small_c_string::run_path_with_cstr;
2207	use crate::sys::{cvt, cvt_r};
2208	use crate::sys_common::ignore_notfound;
2209
2210	pub fn openat_nofollow_dironly(parent_fd: Option<RawFd>, p: &CStr) -> io::Result<OwnedFd> {
2211	let fd = cvt_r(\|\| unsafe {
2212	openat(
2213	parent_fd.unwrap_or(libc::AT_FDCWD),
2214	p.as_ptr(),
2215	libc::O_CLOEXEC \| libc::O_RDONLY \| libc::O_NOFOLLOW \| libc::O_DIRECTORY,
2216	)
2217	})?;
2218	Ok(unsafe { OwnedFd::from_raw_fd(fd) })
2219	}
2220
2221	fn fdreaddir(dir_fd: OwnedFd) -> io::Result<(ReadDir, RawFd)> {
2222	let ptr = unsafe { fdopendir(dir_fd.as_raw_fd()) };
2223	if ptr.is_null() {
2224	return Err(io::Error::last_os_error());
2225	}
2226	let dirp = Dir(ptr);
2227	// file descriptor is automatically closed by libc::closedir() now, so give up ownership
2228	let new_parent_fd = dir_fd.into_raw_fd();
2229	// a valid root is not needed because we do not call any functions involving the full path
2230	// of the `DirEntry`s.
2231	let dummy_root = PathBuf::new();
2232	let inner = InnerReadDir { dirp, root: dummy_root };
2233	Ok((ReadDir::new(inner), new_parent_fd))
2234	}
2235
2236	#[cfg(any(
2237	target_os = "solaris",
2238	target_os = "illumos",
2239	target_os = "haiku",
2240	target_os = "vxworks",
2241	target_os = "aix",
2242	))]
2243	fn is_dir(_ent: &DirEntry) -> Option<bool> {
2244	None
2245	}
2246
2247	#[cfg(not(any(
2248	target_os = "solaris",
2249	target_os = "illumos",
2250	target_os = "haiku",
2251	target_os = "vxworks",
2252	target_os = "aix",
2253	)))]
2254	fn is_dir(ent: &DirEntry) -> Option<bool> {
2255	match ent.entry.d_type {
2256	libc::DT_UNKNOWN => None,
2257	libc::DT_DIR => Some(`true`),
2258	_ => Some(`false`),
2259	}
2260	}
2261
2262	fn is_enoent(result: &io::Result<()>) -> bool {
2263	if let Err(err) = result
2264	&& matches!(err.raw_os_error(), Some(libc::ENOENT))
2265	{
2266	`true`
2267	} else {
2268	`false`
2269	}
2270	}
2271
2272	fn remove_dir_all_recursive(parent_fd: Option<RawFd>, path: &CStr) -> io::Result<()> {
2273	// try opening as directory
2274	let fd = match openat_nofollow_dironly(parent_fd, &path) {
2275	Err(err) if matches!(err.raw_os_error(), Some(libc::ENOTDIR \| libc::ELOOP)) => {
2276	// not a directory - don't traverse further
2277	// (for symlinks, older Linux kernels may return ELOOP instead of ENOTDIR)
2278	return match parent_fd {
2279	// unlink...
2280	Some(parent_fd) => {
2281	cvt(unsafe { unlinkat(parent_fd, path.as_ptr(), `0`) }).map(drop)
2282	}
2283	// ...unless this was supposed to be the deletion root directory
2284	None => Err(err),
2285	};
2286	}
2287	result => result?,
2288	};
2289
2290	// open the directory passing ownership of the fd
2291	let (dir, fd) = fdreaddir(fd)?;
2292	for child in dir {
2293	let child = child?;
2294	let child_name = child.name_cstr();
2295	// we need an inner try block, because if one of these
2296	// directories has already been deleted, then we need to
2297	// continue the loop, not return ok.
2298	let result: io::Result<()> = try {
2299	match is_dir(&child) {
2300	Some(`true`) => {
2301	remove_dir_all_recursive(Some(fd), child_name)?;
2302	}
2303	Some(`false`) => {
2304	cvt(unsafe { unlinkat(fd, child_name.as_ptr(), `0`) })?;
2305	}
2306	None => {
2307	// POSIX specifies that calling unlink()/unlinkat(..., 0) on a directory can succeed
2308	// if the process has the appropriate privileges. This however can causing orphaned
2309	// directories requiring an fsck e.g. on Solaris and Illumos. So we try recursing
2310	// into it first instead of trying to unlink() it.
2311	remove_dir_all_recursive(Some(fd), child_name)?;
2312	}
2313	}
2314	};
2315	if result.is_err() && !is_enoent(&result) {
2316	return result;
2317	}
2318	}
2319
2320	// unlink the directory after removing its contents
2321	ignore_notfound(cvt(unsafe {
2322	unlinkat(parent_fd.unwrap_or(libc::AT_FDCWD), path.as_ptr(), libc::AT_REMOVEDIR)
2323	}))?;
2324	Ok(())
2325	}
2326
2327	fn remove_dir_all_modern(p: &Path) -> io::Result<()> {
2328	// We cannot just call remove_dir_all_recursive() here because that would not delete a passed
2329	// symlink. No need to worry about races, because remove_dir_all_recursive() does not recurse
2330	// into symlinks.
2331	let attr = lstat(p)?;
2332	if attr.file_type().is_symlink() {
2333	crate::fs::remove_file(p)
2334	} else {
2335	run_path_with_cstr(p, &\|p\| remove_dir_all_recursive(None, &p))
2336	}
2337	}
2338
2339	pub fn remove_dir_all(p: &Path) -> io::Result<()> {
2340	remove_dir_all_modern(p)
2341	}
2342	}
2343

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