1 //! Implementation of `std::os` functionality for unix systems
3 #![allow(unused_imports)] // lots of cfg code here
8 use crate::os::unix::prelude::*;
10 use crate::error::Error as StdError;
11 use crate::ffi::{CStr, CString, OsStr, OsString};
16 use crate::path::{self, PathBuf};
22 use crate::sys::memchr;
23 use crate::sys_common::rwlock::{StaticRWLock, StaticRWLockReadGuard};
26 #[cfg(all(target_env = "gnu", not(target_os = "vxworks")))]
27 use crate::sys::weak::weak;
29 use libc::{c_char, c_int, c_void};
31 const TMPBUF_SZ: usize = 128;
34 if #[cfg(target_os = "redox")] {
35 const PATH_SEPARATOR: u8 = b';';
37 const PATH_SEPARATOR: u8 = b':';
42 #[cfg(not(any(target_os = "dragonfly", target_os = "vxworks")))]
46 target_os = "emscripten",
47 target_os = "fuchsia",
50 link_name = "__errno_location"
55 target_os = "openbsd",
56 target_os = "android",
62 #[cfg_attr(any(target_os = "solaris", target_os = "illumos"), link_name = "___errno")]
64 any(target_os = "macos", target_os = "ios", target_os = "freebsd"),
67 #[cfg_attr(target_os = "haiku", link_name = "_errnop")]
68 fn errno_location() -> *mut c_int;
71 /// Returns the platform-specific value of errno
72 #[cfg(not(any(target_os = "dragonfly", target_os = "vxworks")))]
73 pub fn errno() -> i32 {
74 unsafe { (*errno_location()) as i32 }
77 /// Sets the platform-specific value of errno
78 #[cfg(all(not(target_os = "dragonfly"), not(target_os = "vxworks")))] // needed for readdir and syscall!
79 #[allow(dead_code)] // but not all target cfgs actually end up using it
80 pub fn set_errno(e: i32) {
81 unsafe { *errno_location() = e as c_int }
84 #[cfg(target_os = "vxworks")]
85 pub fn errno() -> i32 {
86 unsafe { libc::errnoGet() }
89 #[cfg(target_os = "dragonfly")]
90 pub fn errno() -> i32 {
96 unsafe { errno as i32 }
99 #[cfg(target_os = "dragonfly")]
101 pub fn set_errno(e: i32) {
104 static mut errno: c_int;
112 /// Gets a detailed string description for the given error number.
113 pub fn error_string(errno: i32) -> String {
115 #[cfg_attr(any(target_os = "linux", target_env = "newlib"), link_name = "__xpg_strerror_r")]
116 fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: libc::size_t) -> c_int;
119 let mut buf = [0 as c_char; TMPBUF_SZ];
121 let p = buf.as_mut_ptr();
123 if strerror_r(errno as c_int, p, buf.len()) < 0 {
124 panic!("strerror_r failure");
127 let p = p as *const _;
128 str::from_utf8(CStr::from_ptr(p).to_bytes()).unwrap().to_owned()
132 #[cfg(target_os = "espidf")]
133 pub fn getcwd() -> io::Result<PathBuf> {
134 Ok(PathBuf::from("/"))
137 #[cfg(not(target_os = "espidf"))]
138 pub fn getcwd() -> io::Result<PathBuf> {
139 let mut buf = Vec::with_capacity(512);
142 let ptr = buf.as_mut_ptr() as *mut libc::c_char;
143 if !libc::getcwd(ptr, buf.capacity()).is_null() {
144 let len = CStr::from_ptr(buf.as_ptr() as *const libc::c_char).to_bytes().len();
147 return Ok(PathBuf::from(OsString::from_vec(buf)));
149 let error = io::Error::last_os_error();
150 if error.raw_os_error() != Some(libc::ERANGE) {
155 // Trigger the internal buffer resizing logic of `Vec` by requiring
156 // more space than the current capacity.
157 let cap = buf.capacity();
164 #[cfg(target_os = "espidf")]
165 pub fn chdir(p: &path::Path) -> io::Result<()> {
166 super::unsupported::unsupported()
169 #[cfg(not(target_os = "espidf"))]
170 pub fn chdir(p: &path::Path) -> io::Result<()> {
171 let p: &OsStr = p.as_ref();
172 let p = CString::new(p.as_bytes())?;
173 if unsafe { libc::chdir(p.as_ptr()) } != 0 {
174 return Err(io::Error::last_os_error());
179 pub struct SplitPaths<'a> {
180 iter: iter::Map<slice::Split<'a, u8, fn(&u8) -> bool>, fn(&'a [u8]) -> PathBuf>,
183 pub fn split_paths(unparsed: &OsStr) -> SplitPaths<'_> {
184 fn bytes_to_path(b: &[u8]) -> PathBuf {
185 PathBuf::from(<OsStr as OsStrExt>::from_bytes(b))
187 fn is_separator(b: &u8) -> bool {
190 let unparsed = unparsed.as_bytes();
193 .split(is_separator as fn(&u8) -> bool)
194 .map(bytes_to_path as fn(&[u8]) -> PathBuf),
198 impl<'a> Iterator for SplitPaths<'a> {
200 fn next(&mut self) -> Option<PathBuf> {
203 fn size_hint(&self) -> (usize, Option<usize>) {
204 self.iter.size_hint()
209 pub struct JoinPathsError;
211 pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>
213 I: Iterator<Item = T>,
216 let mut joined = Vec::new();
218 for (i, path) in paths.enumerate() {
219 let path = path.as_ref().as_bytes();
221 joined.push(PATH_SEPARATOR)
223 if path.contains(&PATH_SEPARATOR) {
224 return Err(JoinPathsError);
226 joined.extend_from_slice(path);
228 Ok(OsStringExt::from_vec(joined))
231 impl fmt::Display for JoinPathsError {
232 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
233 write!(f, "path segment contains separator `{}`", char::from(PATH_SEPARATOR))
237 impl StdError for JoinPathsError {
239 fn description(&self) -> &str {
240 "failed to join paths"
244 #[cfg(any(target_os = "freebsd", target_os = "dragonfly"))]
245 pub fn current_exe() -> io::Result<PathBuf> {
248 libc::CTL_KERN as c_int,
249 libc::KERN_PROC as c_int,
250 libc::KERN_PROC_PATHNAME as c_int,
256 mib.len() as libc::c_uint,
263 return Err(io::Error::last_os_error());
265 let mut v: Vec<u8> = Vec::with_capacity(sz);
268 mib.len() as libc::c_uint,
269 v.as_mut_ptr() as *mut libc::c_void,
275 return Err(io::Error::last_os_error());
277 v.set_len(sz - 1); // chop off trailing NUL
278 Ok(PathBuf::from(OsString::from_vec(v)))
282 #[cfg(target_os = "netbsd")]
283 pub fn current_exe() -> io::Result<PathBuf> {
284 fn sysctl() -> io::Result<PathBuf> {
286 let mib = [libc::CTL_KERN, libc::KERN_PROC_ARGS, -1, libc::KERN_PROC_PATHNAME];
287 let mut path_len: usize = 0;
290 mib.len() as libc::c_uint,
297 return Err(io::const_io_error!(
298 io::ErrorKind::Uncategorized,
299 "KERN_PROC_PATHNAME sysctl returned zero-length string",
302 let mut path: Vec<u8> = Vec::with_capacity(path_len);
305 mib.len() as libc::c_uint,
306 path.as_ptr() as *mut libc::c_void,
311 path.set_len(path_len - 1); // chop off NUL
312 Ok(PathBuf::from(OsString::from_vec(path)))
315 fn procfs() -> io::Result<PathBuf> {
316 let curproc_exe = path::Path::new("/proc/curproc/exe");
317 if curproc_exe.is_file() {
318 return crate::fs::read_link(curproc_exe);
320 Err(io::const_io_error!(
321 io::ErrorKind::Uncategorized,
322 "/proc/curproc/exe doesn't point to regular file.",
325 sysctl().or_else(|_| procfs())
328 #[cfg(target_os = "openbsd")]
329 pub fn current_exe() -> io::Result<PathBuf> {
331 let mut mib = [libc::CTL_KERN, libc::KERN_PROC_ARGS, libc::getpid(), libc::KERN_PROC_ARGV];
332 let mib = mib.as_mut_ptr();
333 let mut argv_len = 0;
334 cvt(libc::sysctl(mib, 4, ptr::null_mut(), &mut argv_len, ptr::null_mut(), 0))?;
335 let mut argv = Vec::<*const libc::c_char>::with_capacity(argv_len as usize);
336 cvt(libc::sysctl(mib, 4, argv.as_mut_ptr() as *mut _, &mut argv_len, ptr::null_mut(), 0))?;
337 argv.set_len(argv_len as usize);
338 if argv[0].is_null() {
339 return Err(io::const_io_error!(
340 io::ErrorKind::Uncategorized,
341 "no current exe available",
344 let argv0 = CStr::from_ptr(argv[0]).to_bytes();
345 if argv0[0] == b'.' || argv0.iter().any(|b| *b == b'/') {
346 crate::fs::canonicalize(OsStr::from_bytes(argv0))
348 Ok(PathBuf::from(OsStr::from_bytes(argv0)))
353 #[cfg(any(target_os = "linux", target_os = "android", target_os = "emscripten"))]
354 pub fn current_exe() -> io::Result<PathBuf> {
355 match crate::fs::read_link("/proc/self/exe") {
356 Err(ref e) if e.kind() == io::ErrorKind::NotFound => Err(io::const_io_error!(
357 io::ErrorKind::Uncategorized,
358 "no /proc/self/exe available. Is /proc mounted?",
364 #[cfg(any(target_os = "macos", target_os = "ios"))]
365 pub fn current_exe() -> io::Result<PathBuf> {
368 libc::_NSGetExecutablePath(ptr::null_mut(), &mut sz);
370 return Err(io::Error::last_os_error());
372 let mut v: Vec<u8> = Vec::with_capacity(sz as usize);
373 let err = libc::_NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
375 return Err(io::Error::last_os_error());
377 v.set_len(sz as usize - 1); // chop off trailing NUL
378 Ok(PathBuf::from(OsString::from_vec(v)))
382 #[cfg(any(target_os = "solaris", target_os = "illumos"))]
383 pub fn current_exe() -> io::Result<PathBuf> {
384 if let Ok(path) = crate::fs::read_link("/proc/self/path/a.out") {
388 let path = libc::getexecname();
390 Err(io::Error::last_os_error())
392 let filename = CStr::from_ptr(path).to_bytes();
393 let path = PathBuf::from(<OsStr as OsStrExt>::from_bytes(filename));
395 // Prepend a current working directory to the path if
396 // it doesn't contain an absolute pathname.
397 if filename[0] == b'/' { Ok(path) } else { getcwd().map(|cwd| cwd.join(path)) }
403 #[cfg(target_os = "haiku")]
404 pub fn current_exe() -> io::Result<PathBuf> {
406 let mut info: mem::MaybeUninit<libc::image_info> = mem::MaybeUninit::uninit();
407 let mut cookie: i32 = 0;
408 // the executable can be found at team id 0
409 let result = libc::_get_next_image_info(
413 mem::size_of::<libc::image_info>(),
416 use crate::io::ErrorKind;
417 Err(io::const_io_error!(ErrorKind::Uncategorized, "Error getting executable path"))
419 let name = CStr::from_ptr((*info.as_ptr()).name.as_ptr()).to_bytes();
420 Ok(PathBuf::from(OsStr::from_bytes(name)))
425 #[cfg(target_os = "redox")]
426 pub fn current_exe() -> io::Result<PathBuf> {
427 crate::fs::read_to_string("sys:exe").map(PathBuf::from)
430 #[cfg(any(target_os = "fuchsia", target_os = "l4re"))]
431 pub fn current_exe() -> io::Result<PathBuf> {
432 use crate::io::ErrorKind;
433 Err(io::const_io_error!(ErrorKind::Unsupported, "Not yet implemented!"))
436 #[cfg(target_os = "vxworks")]
437 pub fn current_exe() -> io::Result<PathBuf> {
444 let exe_path = env::args().next().unwrap();
445 let path = path::Path::new(&exe_path);
449 #[cfg(target_os = "espidf")]
450 pub fn current_exe() -> io::Result<PathBuf> {
451 super::unsupported::unsupported()
455 iter: vec::IntoIter<(OsString, OsString)>,
458 impl !Send for Env {}
459 impl !Sync for Env {}
461 impl Iterator for Env {
462 type Item = (OsString, OsString);
463 fn next(&mut self) -> Option<(OsString, OsString)> {
466 fn size_hint(&self) -> (usize, Option<usize>) {
467 self.iter.size_hint()
471 #[cfg(target_os = "macos")]
472 pub unsafe fn environ() -> *mut *const *const c_char {
473 libc::_NSGetEnviron() as *mut *const *const c_char
476 #[cfg(not(target_os = "macos"))]
477 pub unsafe fn environ() -> *mut *const *const c_char {
479 static mut environ: *const *const c_char;
481 ptr::addr_of_mut!(environ)
484 static ENV_LOCK: StaticRWLock = StaticRWLock::new();
486 pub fn env_read_lock() -> StaticRWLockReadGuard {
490 /// Returns a vector of (variable, value) byte-vector pairs for all the
491 /// environment variables of the current process.
492 pub fn env() -> Env {
494 let _guard = env_read_lock();
495 let mut environ = *environ();
496 let mut result = Vec::new();
497 if !environ.is_null() {
498 while !(*environ).is_null() {
499 if let Some(key_value) = parse(CStr::from_ptr(*environ).to_bytes()) {
500 result.push(key_value);
502 environ = environ.add(1);
505 return Env { iter: result.into_iter() };
508 fn parse(input: &[u8]) -> Option<(OsString, OsString)> {
509 // Strategy (copied from glibc): Variable name and value are separated
510 // by an ASCII equals sign '='. Since a variable name must not be
511 // empty, allow variable names starting with an equals sign. Skip all
513 if input.is_empty() {
516 let pos = memchr::memchr(b'=', &input[1..]).map(|p| p + 1);
519 OsStringExt::from_vec(input[..p].to_vec()),
520 OsStringExt::from_vec(input[p + 1..].to_vec()),
526 pub fn getenv(k: &OsStr) -> Option<OsString> {
527 // environment variables with a nul byte can't be set, so their value is
528 // always None as well
529 let k = CString::new(k.as_bytes()).ok()?;
531 let _guard = env_read_lock();
532 let s = libc::getenv(k.as_ptr()) as *const libc::c_char;
536 Some(OsStringExt::from_vec(CStr::from_ptr(s).to_bytes().to_vec()))
541 pub fn setenv(k: &OsStr, v: &OsStr) -> io::Result<()> {
542 let k = CString::new(k.as_bytes())?;
543 let v = CString::new(v.as_bytes())?;
546 let _guard = ENV_LOCK.write();
547 cvt(libc::setenv(k.as_ptr(), v.as_ptr(), 1)).map(drop)
551 pub fn unsetenv(n: &OsStr) -> io::Result<()> {
552 let nbuf = CString::new(n.as_bytes())?;
555 let _guard = ENV_LOCK.write();
556 cvt(libc::unsetenv(nbuf.as_ptr())).map(drop)
560 #[cfg(not(target_os = "espidf"))]
561 pub fn page_size() -> usize {
562 unsafe { libc::sysconf(libc::_SC_PAGESIZE) as usize }
565 pub fn temp_dir() -> PathBuf {
566 crate::env::var_os("TMPDIR").map(PathBuf::from).unwrap_or_else(|| {
567 if cfg!(target_os = "android") {
568 PathBuf::from("/data/local/tmp")
570 PathBuf::from("/tmp")
575 pub fn home_dir() -> Option<PathBuf> {
576 return crate::env::var_os("HOME").or_else(|| unsafe { fallback() }).map(PathBuf::from);
579 target_os = "android",
581 target_os = "emscripten",
583 target_os = "vxworks",
586 unsafe fn fallback() -> Option<OsString> {
590 target_os = "android",
592 target_os = "emscripten",
594 target_os = "vxworks",
597 unsafe fn fallback() -> Option<OsString> {
598 let amt = match libc::sysconf(libc::_SC_GETPW_R_SIZE_MAX) {
599 n if n < 0 => 512 as usize,
602 let mut buf = Vec::with_capacity(amt);
603 let mut passwd: libc::passwd = mem::zeroed();
604 let mut result = ptr::null_mut();
605 match libc::getpwuid_r(
612 0 if !result.is_null() => {
613 let ptr = passwd.pw_dir as *const _;
614 let bytes = CStr::from_ptr(ptr).to_bytes().to_vec();
615 Some(OsStringExt::from_vec(bytes))
622 pub fn exit(code: i32) -> ! {
623 unsafe { libc::exit(code as c_int) }
626 pub fn getpid() -> u32 {
627 unsafe { libc::getpid() as u32 }
630 pub fn getppid() -> u32 {
631 unsafe { libc::getppid() as u32 }
634 #[cfg(all(target_os = "linux", target_env = "gnu"))]
635 pub fn glibc_version() -> Option<(usize, usize)> {
637 fn gnu_get_libc_version() -> *const libc::c_char;
639 let version_cstr = unsafe { CStr::from_ptr(gnu_get_libc_version()) };
640 if let Ok(version_str) = version_cstr.to_str() {
641 parse_glibc_version(version_str)
647 // Returns Some((major, minor)) if the string is a valid "x.y" version,
648 // ignoring any extra dot-separated parts. Otherwise return None.
649 #[cfg(all(target_os = "linux", target_env = "gnu"))]
650 fn parse_glibc_version(version: &str) -> Option<(usize, usize)> {
651 let mut parsed_ints = version.split('.').map(str::parse::<usize>).fuse();
652 match (parsed_ints.next(), parsed_ints.next()) {
653 (Some(Ok(major)), Some(Ok(minor))) => Some((major, minor)),