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