1 //! Implementation of `std::os` functionality for unix systems
3 #![allow(unused_imports)] // lots of cfg code here
5 use crate::os::unix::prelude::*;
7 use crate::error::Error as StdError;
8 use crate::ffi::{CString, CStr, OsString, OsStr};
12 use crate::marker::PhantomData;
15 use crate::path::{self, PathBuf};
19 use crate::sys_common::mutex::{Mutex, MutexGuard};
24 use libc::{c_int, c_char, c_void};
26 const TMPBUF_SZ: usize = 128;
30 #[cfg(not(target_os = "dragonfly"))]
31 #[cfg_attr(any(target_os = "linux",
32 target_os = "emscripten",
33 target_os = "fuchsia",
35 link_name = "__errno_location")]
36 #[cfg_attr(any(target_os = "bitrig",
38 target_os = "openbsd",
39 target_os = "android",
41 target_env = "newlib"),
42 link_name = "__errno")]
43 #[cfg_attr(target_os = "solaris", link_name = "___errno")]
44 #[cfg_attr(any(target_os = "macos",
46 target_os = "freebsd"),
47 link_name = "__error")]
48 #[cfg_attr(target_os = "haiku", link_name = "_errnop")]
49 fn errno_location() -> *mut c_int;
52 /// Returns the platform-specific value of errno
53 #[cfg(not(target_os = "dragonfly"))]
54 pub fn errno() -> i32 {
56 (*errno_location()) as i32
60 /// Sets the platform-specific value of errno
61 #[cfg(all(not(target_os = "linux"),
62 not(target_os = "dragonfly")))] // needed for readdir and syscall!
63 pub fn set_errno(e: i32) {
65 *errno_location() = e as c_int
69 #[cfg(target_os = "dragonfly")]
70 pub fn errno() -> i32 {
76 unsafe { errno as i32 }
79 #[cfg(target_os = "dragonfly")]
80 pub fn set_errno(e: i32) {
83 static mut errno: c_int;
91 /// Gets a detailed string description for the given error number.
92 pub fn error_string(errno: i32) -> String {
94 #[cfg_attr(any(target_os = "linux", target_env = "newlib"),
95 link_name = "__xpg_strerror_r")]
96 fn strerror_r(errnum: c_int, buf: *mut c_char,
97 buflen: libc::size_t) -> c_int;
100 let mut buf = [0 as c_char; TMPBUF_SZ];
102 let p = buf.as_mut_ptr();
104 if strerror_r(errno as c_int, p, buf.len()) < 0 {
105 panic!("strerror_r failure");
108 let p = p as *const _;
109 str::from_utf8(CStr::from_ptr(p).to_bytes()).unwrap().to_owned()
113 pub fn getcwd() -> io::Result<PathBuf> {
114 let mut buf = Vec::with_capacity(512);
117 let ptr = buf.as_mut_ptr() as *mut libc::c_char;
118 if !libc::getcwd(ptr, buf.capacity()).is_null() {
119 let len = CStr::from_ptr(buf.as_ptr() as *const libc::c_char).to_bytes().len();
122 return Ok(PathBuf::from(OsString::from_vec(buf)));
124 let error = io::Error::last_os_error();
125 if error.raw_os_error() != Some(libc::ERANGE) {
130 // Trigger the internal buffer resizing logic of `Vec` by requiring
131 // more space than the current capacity.
132 let cap = buf.capacity();
139 pub fn chdir(p: &path::Path) -> io::Result<()> {
140 let p: &OsStr = p.as_ref();
141 let p = CString::new(p.as_bytes())?;
143 match libc::chdir(p.as_ptr()) == (0 as c_int) {
145 false => Err(io::Error::last_os_error()),
150 pub struct SplitPaths<'a> {
151 iter: iter::Map<slice::Split<'a, u8, fn(&u8) -> bool>,
152 fn(&'a [u8]) -> PathBuf>,
155 pub fn split_paths(unparsed: &OsStr) -> SplitPaths<'_> {
156 fn bytes_to_path(b: &[u8]) -> PathBuf {
157 PathBuf::from(<OsStr as OsStrExt>::from_bytes(b))
159 fn is_colon(b: &u8) -> bool { *b == b':' }
160 let unparsed = unparsed.as_bytes();
162 iter: unparsed.split(is_colon as fn(&u8) -> bool)
163 .map(bytes_to_path as fn(&[u8]) -> PathBuf)
167 impl<'a> Iterator for SplitPaths<'a> {
169 fn next(&mut self) -> Option<PathBuf> { self.iter.next() }
170 fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
174 pub struct JoinPathsError;
176 pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>
177 where I: Iterator<Item=T>, T: AsRef<OsStr>
179 let mut joined = Vec::new();
182 for (i, path) in paths.enumerate() {
183 let path = path.as_ref().as_bytes();
184 if i > 0 { joined.push(sep) }
185 if path.contains(&sep) {
186 return Err(JoinPathsError)
188 joined.extend_from_slice(path);
190 Ok(OsStringExt::from_vec(joined))
193 impl fmt::Display for JoinPathsError {
194 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
195 "path segment contains separator `:`".fmt(f)
199 impl StdError for JoinPathsError {
200 fn description(&self) -> &str { "failed to join paths" }
203 #[cfg(any(target_os = "freebsd", target_os = "dragonfly"))]
204 pub fn current_exe() -> io::Result<PathBuf> {
206 let mut mib = [libc::CTL_KERN as c_int,
207 libc::KERN_PROC as c_int,
208 libc::KERN_PROC_PATHNAME as c_int,
211 cvt(libc::sysctl(mib.as_mut_ptr(), mib.len() as libc::c_uint,
212 ptr::null_mut(), &mut sz, ptr::null_mut(), 0))?;
214 return Err(io::Error::last_os_error())
216 let mut v: Vec<u8> = Vec::with_capacity(sz);
217 cvt(libc::sysctl(mib.as_mut_ptr(), mib.len() as libc::c_uint,
218 v.as_mut_ptr() as *mut libc::c_void, &mut sz,
219 ptr::null_mut(), 0))?;
221 return Err(io::Error::last_os_error());
223 v.set_len(sz - 1); // chop off trailing NUL
224 Ok(PathBuf::from(OsString::from_vec(v)))
228 #[cfg(target_os = "netbsd")]
229 pub fn current_exe() -> io::Result<PathBuf> {
230 fn sysctl() -> io::Result<PathBuf> {
232 let mib = [libc::CTL_KERN, libc::KERN_PROC_ARGS, -1, libc::KERN_PROC_PATHNAME];
233 let mut path_len: usize = 0;
234 cvt(libc::sysctl(mib.as_ptr(), mib.len() as libc::c_uint,
235 ptr::null_mut(), &mut path_len,
238 return Err(io::Error::new(io::ErrorKind::Other,
239 "KERN_PROC_PATHNAME sysctl returned zero-length string"))
241 let mut path: Vec<u8> = Vec::with_capacity(path_len);
242 cvt(libc::sysctl(mib.as_ptr(), mib.len() as libc::c_uint,
243 path.as_ptr() as *mut libc::c_void, &mut path_len,
245 path.set_len(path_len - 1); // chop off NUL
246 Ok(PathBuf::from(OsString::from_vec(path)))
249 fn procfs() -> io::Result<PathBuf> {
250 let curproc_exe = path::Path::new("/proc/curproc/exe");
251 if curproc_exe.is_file() {
252 return crate::fs::read_link(curproc_exe);
254 Err(io::Error::new(io::ErrorKind::Other,
255 "/proc/curproc/exe doesn't point to regular file."))
257 sysctl().or_else(|_| procfs())
260 #[cfg(any(target_os = "bitrig", target_os = "openbsd"))]
261 pub fn current_exe() -> io::Result<PathBuf> {
263 let mut mib = [libc::CTL_KERN,
264 libc::KERN_PROC_ARGS,
266 libc::KERN_PROC_ARGV];
267 let mib = mib.as_mut_ptr();
268 let mut argv_len = 0;
269 cvt(libc::sysctl(mib, 4, ptr::null_mut(), &mut argv_len,
270 ptr::null_mut(), 0))?;
271 let mut argv = Vec::<*const libc::c_char>::with_capacity(argv_len as usize);
272 cvt(libc::sysctl(mib, 4, argv.as_mut_ptr() as *mut _,
273 &mut argv_len, ptr::null_mut(), 0))?;
274 argv.set_len(argv_len as usize);
275 if argv[0].is_null() {
276 return Err(io::Error::new(io::ErrorKind::Other,
277 "no current exe available"))
279 let argv0 = CStr::from_ptr(argv[0]).to_bytes();
280 if argv0[0] == b'.' || argv0.iter().any(|b| *b == b'/') {
281 crate::fs::canonicalize(OsStr::from_bytes(argv0))
283 Ok(PathBuf::from(OsStr::from_bytes(argv0)))
288 #[cfg(any(target_os = "linux", target_os = "android", target_os = "emscripten"))]
289 pub fn current_exe() -> io::Result<PathBuf> {
290 match crate::fs::read_link("/proc/self/exe") {
291 Err(ref e) if e.kind() == io::ErrorKind::NotFound => {
293 io::ErrorKind::Other,
294 "no /proc/self/exe available. Is /proc mounted?"
301 #[cfg(any(target_os = "macos", target_os = "ios"))]
302 pub fn current_exe() -> io::Result<PathBuf> {
304 fn _NSGetExecutablePath(buf: *mut libc::c_char,
305 bufsize: *mut u32) -> libc::c_int;
309 _NSGetExecutablePath(ptr::null_mut(), &mut sz);
310 if sz == 0 { return Err(io::Error::last_os_error()); }
311 let mut v: Vec<u8> = Vec::with_capacity(sz as usize);
312 let err = _NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
313 if err != 0 { return Err(io::Error::last_os_error()); }
314 v.set_len(sz as usize - 1); // chop off trailing NUL
315 Ok(PathBuf::from(OsString::from_vec(v)))
319 #[cfg(any(target_os = "solaris"))]
320 pub fn current_exe() -> io::Result<PathBuf> {
322 fn getexecname() -> *const c_char;
325 let path = getexecname();
327 Err(io::Error::last_os_error())
329 let filename = CStr::from_ptr(path).to_bytes();
330 let path = PathBuf::from(<OsStr as OsStrExt>::from_bytes(filename));
332 // Prepend a current working directory to the path if
333 // it doesn't contain an absolute pathname.
334 if filename[0] == b'/' {
337 getcwd().map(|cwd| cwd.join(path))
343 #[cfg(target_os = "haiku")]
344 pub fn current_exe() -> io::Result<PathBuf> {
345 // Use Haiku's image info functions
352 init_routine: *mut libc::c_void, // function pointer
353 term_routine: *mut libc::c_void, // function pointer
356 name: [libc::c_char; 1024], // MAXPATHLEN
357 text: *mut libc::c_void,
358 data: *mut libc::c_void,
367 fn _get_next_image_info(team_id: i32, cookie: *mut i32,
368 info: *mut image_info, size: i32) -> i32;
371 let mut info: image_info = mem::zeroed();
372 let mut cookie: i32 = 0;
373 // the executable can be found at team id 0
374 let result = _get_next_image_info(0, &mut cookie, &mut info,
375 mem::size_of::<image_info>() as i32);
377 use crate::io::ErrorKind;
378 Err(io::Error::new(ErrorKind::Other, "Error getting executable path"))
380 let name = CStr::from_ptr(info.name.as_ptr()).to_bytes();
381 Ok(PathBuf::from(OsStr::from_bytes(name)))
386 #[cfg(any(target_os = "fuchsia", target_os = "l4re", target_os = "hermit"))]
387 pub fn current_exe() -> io::Result<PathBuf> {
388 use crate::io::ErrorKind;
389 Err(io::Error::new(ErrorKind::Other, "Not yet implemented!"))
393 iter: vec::IntoIter<(OsString, OsString)>,
394 _dont_send_or_sync_me: PhantomData<*mut ()>,
397 impl Iterator for Env {
398 type Item = (OsString, OsString);
399 fn next(&mut self) -> Option<(OsString, OsString)> { self.iter.next() }
400 fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
403 #[cfg(target_os = "macos")]
404 pub unsafe fn environ() -> *mut *const *const c_char {
405 extern { fn _NSGetEnviron() -> *mut *const *const c_char; }
409 #[cfg(not(target_os = "macos"))]
410 pub unsafe fn environ() -> *mut *const *const c_char {
411 extern { static mut environ: *const *const c_char; }
415 pub unsafe fn env_lock() -> MutexGuard<'static> {
416 // We never call `ENV_LOCK.init()`, so it is UB to attempt to
417 // acquire this mutex reentrantly!
418 static ENV_LOCK: Mutex = Mutex::new();
422 /// Returns a vector of (variable, value) byte-vector pairs for all the
423 /// environment variables of the current process.
424 pub fn env() -> Env {
426 let _guard = env_lock();
427 let mut environ = *environ();
428 let mut result = Vec::new();
429 while environ != ptr::null() && *environ != ptr::null() {
430 if let Some(key_value) = parse(CStr::from_ptr(*environ).to_bytes()) {
431 result.push(key_value);
433 environ = environ.offset(1);
436 iter: result.into_iter(),
437 _dont_send_or_sync_me: PhantomData,
441 fn parse(input: &[u8]) -> Option<(OsString, OsString)> {
442 // Strategy (copied from glibc): Variable name and value are separated
443 // by an ASCII equals sign '='. Since a variable name must not be
444 // empty, allow variable names starting with an equals sign. Skip all
446 if input.is_empty() {
449 let pos = memchr::memchr(b'=', &input[1..]).map(|p| p + 1);
451 OsStringExt::from_vec(input[..p].to_vec()),
452 OsStringExt::from_vec(input[p+1..].to_vec()),
457 pub fn getenv(k: &OsStr) -> io::Result<Option<OsString>> {
458 // environment variables with a nul byte can't be set, so their value is
459 // always None as well
460 let k = CString::new(k.as_bytes())?;
462 let _guard = env_lock();
463 let s = libc::getenv(k.as_ptr()) as *const libc::c_char;
464 let ret = if s.is_null() {
467 Some(OsStringExt::from_vec(CStr::from_ptr(s).to_bytes().to_vec()))
473 pub fn setenv(k: &OsStr, v: &OsStr) -> io::Result<()> {
474 let k = CString::new(k.as_bytes())?;
475 let v = CString::new(v.as_bytes())?;
478 let _guard = env_lock();
479 cvt(libc::setenv(k.as_ptr(), v.as_ptr(), 1)).map(|_| ())
483 pub fn unsetenv(n: &OsStr) -> io::Result<()> {
484 let nbuf = CString::new(n.as_bytes())?;
487 let _guard = env_lock();
488 cvt(libc::unsetenv(nbuf.as_ptr())).map(|_| ())
492 pub fn page_size() -> usize {
494 libc::sysconf(libc::_SC_PAGESIZE) as usize
498 pub fn temp_dir() -> PathBuf {
499 crate::env::var_os("TMPDIR").map(PathBuf::from).unwrap_or_else(|| {
500 if cfg!(target_os = "android") {
501 PathBuf::from("/data/local/tmp")
503 PathBuf::from("/tmp")
508 pub fn home_dir() -> Option<PathBuf> {
509 return crate::env::var_os("HOME").or_else(|| unsafe {
511 }).map(PathBuf::from);
513 #[cfg(any(target_os = "android",
515 target_os = "emscripten"))]
516 unsafe fn fallback() -> Option<OsString> { None }
517 #[cfg(not(any(target_os = "android",
519 target_os = "emscripten")))]
520 unsafe fn fallback() -> Option<OsString> {
521 let amt = match libc::sysconf(libc::_SC_GETPW_R_SIZE_MAX) {
522 n if n < 0 => 512 as usize,
525 let mut buf = Vec::with_capacity(amt);
526 let mut passwd: libc::passwd = mem::zeroed();
527 let mut result = ptr::null_mut();
528 match libc::getpwuid_r(libc::getuid(), &mut passwd, buf.as_mut_ptr(),
529 buf.capacity(), &mut result) {
530 0 if !result.is_null() => {
531 let ptr = passwd.pw_dir as *const _;
532 let bytes = CStr::from_ptr(ptr).to_bytes().to_vec();
533 Some(OsStringExt::from_vec(bytes))
540 pub fn exit(code: i32) -> ! {
541 unsafe { libc::exit(code as c_int) }
544 pub fn getpid() -> u32 {
545 unsafe { libc::getpid() as u32 }
548 pub fn getppid() -> u32 {
549 unsafe { libc::getppid() as u32 }
552 #[cfg(target_env = "gnu")]
553 pub fn glibc_version() -> Option<(usize, usize)> {
554 if let Some(Ok(version_str)) = glibc_version_cstr().map(CStr::to_str) {
555 parse_glibc_version(version_str)
561 #[cfg(target_env = "gnu")]
562 fn glibc_version_cstr() -> Option<&'static CStr> {
564 fn gnu_get_libc_version() -> *const libc::c_char
566 if let Some(f) = gnu_get_libc_version.get() {
567 unsafe { Some(CStr::from_ptr(f())) }
573 // Returns Some((major, minor)) if the string is a valid "x.y" version,
574 // ignoring any extra dot-separated parts. Otherwise return None.
575 #[cfg(target_env = "gnu")]
576 fn parse_glibc_version(version: &str) -> Option<(usize, usize)> {
577 let mut parsed_ints = version.split('.').map(str::parse::<usize>).fuse();
578 match (parsed_ints.next(), parsed_ints.next()) {
579 (Some(Ok(major)), Some(Ok(minor))) => Some((major, minor)),
584 #[cfg(all(test, target_env = "gnu"))]
589 fn test_glibc_version() {
590 // This mostly just tests that the weak linkage doesn't panic wildly...
595 fn test_parse_glibc_version() {
597 ("0.0", Some((0, 0))),
598 ("01.+2", Some((1, 2))),
599 ("3.4.5.six", Some((3, 4))),
605 for &(version_str, parsed) in cases.iter() {
606 assert_eq!(parsed, parse_glibc_version(version_str));