src/libstd/sys/unix/os.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Implementation of `std::os` functionality for unix systems
  12
  13 #![allow(unused_imports)] // lots of cfg code here
  14
  15 use prelude::v1::*;
  16 use os::unix::prelude::*;
  17
  18 use error::Error as StdError;
  19 use ffi::{CString, CStr, OsString, OsStr};
  20 use fmt;
  21 use io;
  22 use iter;
  23 use libc::{self, c_int, c_char, c_void};
  24 use mem;
  25 #[allow(deprecated)] use old_io::{IoError, IoResult};
  26 use ptr;
  27 use path::{self, PathBuf};
  28 use slice;
  29 use str;
  30 use sys::c;
  31 use sys::fd;
  32 use sys::fs::FileDesc;
  33 use vec;
  34
  35 const BUF_BYTES: usize = 2048;
  36 const TMPBUF_SZ: usize = 128;
  37
  38 fn bytes2path(b: &[u8]) -> PathBuf {
  39     PathBuf::from(<OsStr as OsStrExt>::from_bytes(b))
  40 }
  41
  42 fn os2path(os: OsString) -> PathBuf {
  43     bytes2path(os.as_bytes())
  44 }
  45
  46 /// Returns the platform-specific value of errno
  47 pub fn errno() -> i32 {
  48     #[cfg(any(target_os = "macos",
  49               target_os = "ios",
  50               target_os = "freebsd"))]
  51     unsafe fn errno_location() -> *const c_int {
  52         extern { fn __error() -> *const c_int; }
  53         __error()
  54     }
  55
  56     #[cfg(target_os = "bitrig")]
  57     fn errno_location() -> *const c_int {
  58         extern {
  59             fn __errno() -> *const c_int;
  60         }
  61         unsafe {
  62             __errno()
  63         }
  64     }
  65
  66     #[cfg(target_os = "dragonfly")]
  67     unsafe fn errno_location() -> *const c_int {
  68         extern { fn __dfly_error() -> *const c_int; }
  69         __dfly_error()
  70     }
  71
  72     #[cfg(target_os = "openbsd")]
  73     unsafe fn errno_location() -> *const c_int {
  74         extern { fn __errno() -> *const c_int; }
  75         __errno()
  76     }
  77
  78     #[cfg(any(target_os = "linux", target_os = "android"))]
  79     unsafe fn errno_location() -> *const c_int {
  80         extern { fn __errno_location() -> *const c_int; }
  81         __errno_location()
  82     }
  83
  84     unsafe {
  85         (*errno_location()) as i32
  86     }
  87 }
  88
  89 /// Get a detailed string description for the given error number
  90 pub fn error_string(errno: i32) -> String {
  91     #[cfg(target_os = "linux")]
  92     extern {
  93         #[link_name = "__xpg_strerror_r"]
  94         fn strerror_r(errnum: c_int, buf: *mut c_char,
  95                       buflen: libc::size_t) -> c_int;
  96     }
  97     #[cfg(not(target_os = "linux"))]
  98     extern {
  99         fn strerror_r(errnum: c_int, buf: *mut c_char,
 100                       buflen: libc::size_t) -> c_int;
 101     }
 102
 103     let mut buf = [0 as c_char; TMPBUF_SZ];
 104
 105     let p = buf.as_mut_ptr();
 106     unsafe {
 107         if strerror_r(errno as c_int, p, buf.len() as libc::size_t) < 0 {
 108             panic!("strerror_r failure");
 109         }
 110
 111         let p = p as *const _;
 112         str::from_utf8(CStr::from_ptr(p).to_bytes()).unwrap().to_string()
 113     }
 114 }
 115
 116 pub fn getcwd() -> io::Result<PathBuf> {
 117     let mut buf = [0 as c_char; BUF_BYTES];
 118     unsafe {
 119         if libc::getcwd(buf.as_mut_ptr(), buf.len() as libc::size_t).is_null() {
 120             Err(io::Error::last_os_error())
 121         } else {
 122             Ok(bytes2path(CStr::from_ptr(buf.as_ptr()).to_bytes()))
 123         }
 124     }
 125 }
 126
 127 pub fn chdir(p: &path::Path) -> io::Result<()> {
 128     let p: &OsStr = p.as_ref();
 129     let p = try!(CString::new(p.as_bytes()));
 130     unsafe {
 131         match libc::chdir(p.as_ptr()) == (0 as c_int) {
 132             true => Ok(()),
 133             false => Err(io::Error::last_os_error()),
 134         }
 135     }
 136 }
 137
 138 pub struct SplitPaths<'a> {
 139     iter: iter::Map<slice::Split<'a, u8, fn(&u8) -> bool>,
 140                     fn(&'a [u8]) -> PathBuf>,
 141 }
 142
 143 pub fn split_paths<'a>(unparsed: &'a OsStr) -> SplitPaths<'a> {
 144     fn is_colon(b: &u8) -> bool { *b == b':' }
 145     let unparsed = unparsed.as_bytes();
 146     SplitPaths {
 147         iter: unparsed.split(is_colon as fn(&u8) -> bool)
 148                       .map(bytes2path as fn(&'a [u8]) -> PathBuf)
 149     }
 150 }
 151
 152 impl<'a> Iterator for SplitPaths<'a> {
 153     type Item = PathBuf;
 154     fn next(&mut self) -> Option<PathBuf> { self.iter.next() }
 155     fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
 156 }
 157
 158 #[derive(Debug)]
 159 pub struct JoinPathsError;
 160
 161 pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>
 162     where I: Iterator<Item=T>, T: AsRef<OsStr>
 163 {
 164     let mut joined = Vec::new();
 165     let sep = b':';
 166
 167     for (i, path) in paths.enumerate() {
 168         let path = path.as_ref().as_bytes();
 169         if i > 0 { joined.push(sep) }
 170         if path.contains(&sep) {
 171             return Err(JoinPathsError)
 172         }
 173         joined.push_all(path);
 174     }
 175     Ok(OsStringExt::from_vec(joined))
 176 }
 177
 178 impl fmt::Display for JoinPathsError {
 179     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 180         "path segment contains separator `:`".fmt(f)
 181     }
 182 }
 183
 184 impl StdError for JoinPathsError {
 185     fn description(&self) -> &str { "failed to join paths" }
 186 }
 187
 188 #[cfg(target_os = "freebsd")]
 189 pub fn current_exe() -> io::Result<PathBuf> {
 190     unsafe {
 191         use libc::funcs::bsd44::*;
 192         use libc::consts::os::extra::*;
 193         let mut mib = vec![CTL_KERN as c_int,
 194                            KERN_PROC as c_int,
 195                            KERN_PROC_PATHNAME as c_int,
 196                            -1 as c_int];
 197         let mut sz: libc::size_t = 0;
 198         let err = sysctl(mib.as_mut_ptr(), mib.len() as ::libc::c_uint,
 199                          ptr::null_mut(), &mut sz, ptr::null_mut(),
 200                          0 as libc::size_t);
 201         if err != 0 { return Err(io::Error::last_os_error()); }
 202         if sz == 0 { return Err(io::Error::last_os_error()); }
 203         let mut v: Vec<u8> = Vec::with_capacity(sz as usize);
 204         let err = sysctl(mib.as_mut_ptr(), mib.len() as ::libc::c_uint,
 205                          v.as_mut_ptr() as *mut libc::c_void, &mut sz,
 206                          ptr::null_mut(), 0 as libc::size_t);
 207         if err != 0 { return Err(io::Error::last_os_error()); }
 208         if sz == 0 { return Err(io::Error::last_os_error()); }
 209         v.set_len(sz as usize - 1); // chop off trailing NUL
 210         Ok(PathBuf::from(OsString::from_vec(v)))
 211     }
 212 }
 213
 214 #[cfg(target_os = "dragonfly")]
 215 pub fn current_exe() -> io::Result<PathBuf> {
 216     ::fs::read_link("/proc/curproc/file")
 217 }
 218
 219 #[cfg(any(target_os = "bitrig", target_os = "openbsd"))]
 220 pub fn current_exe() -> io::Result<PathBuf> {
 221     use sync::{StaticMutex, MUTEX_INIT};
 222     static LOCK: StaticMutex = MUTEX_INIT;
 223
 224     extern {
 225         fn rust_current_exe() -> *const c_char;
 226     }
 227
 228     let _guard = LOCK.lock();
 229
 230     unsafe {
 231         let v = rust_current_exe();
 232         if v.is_null() {
 233             Err(io::Error::last_os_error())
 234         } else {
 235             let vec = CStr::from_ptr(v).to_bytes().to_vec();
 236             Ok(PathBuf::from(OsString::from_vec(vec)))
 237         }
 238     }
 239 }
 240
 241 #[cfg(any(target_os = "linux", target_os = "android"))]
 242 pub fn current_exe() -> io::Result<PathBuf> {
 243     ::fs::read_link("/proc/self/exe")
 244 }
 245
 246 #[cfg(any(target_os = "macos", target_os = "ios"))]
 247 pub fn current_exe() -> io::Result<PathBuf> {
 248     unsafe {
 249         use libc::funcs::extra::_NSGetExecutablePath;
 250         let mut sz: u32 = 0;
 251         _NSGetExecutablePath(ptr::null_mut(), &mut sz);
 252         if sz == 0 { return Err(io::Error::last_os_error()); }
 253         let mut v: Vec<u8> = Vec::with_capacity(sz as usize);
 254         let err = _NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
 255         if err != 0 { return Err(io::Error::last_os_error()); }
 256         v.set_len(sz as usize - 1); // chop off trailing NUL
 257         Ok(PathBuf::from(OsString::from_vec(v)))
 258     }
 259 }
 260
 261 pub struct Args {
 262     iter: vec::IntoIter<OsString>,
 263     _dont_send_or_sync_me: *mut (),
 264 }
 265
 266 impl Iterator for Args {
 267     type Item = OsString;
 268     fn next(&mut self) -> Option<OsString> { self.iter.next() }
 269     fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
 270 }
 271
 272 impl ExactSizeIterator for Args {
 273     fn len(&self) -> usize { self.iter.len() }
 274 }
 275
 276 /// Returns the command line arguments
 277 ///
 278 /// Returns a list of the command line arguments.
 279 #[cfg(target_os = "macos")]
 280 pub fn args() -> Args {
 281     extern {
 282         // These functions are in crt_externs.h.
 283         fn _NSGetArgc() -> *mut c_int;
 284         fn _NSGetArgv() -> *mut *mut *mut c_char;
 285     }
 286
 287     let vec = unsafe {
 288         let (argc, argv) = (*_NSGetArgc() as isize,
 289                             *_NSGetArgv() as *const *const c_char);
 290         (0.. argc as isize).map(|i| {
 291             let bytes = CStr::from_ptr(*argv.offset(i)).to_bytes().to_vec();
 292             OsStringExt::from_vec(bytes)
 293         }).collect::<Vec<_>>()
 294     };
 295     Args {
 296         iter: vec.into_iter(),
 297         _dont_send_or_sync_me: 0 as *mut (),
 298     }
 299 }
 300
 301 // As _NSGetArgc and _NSGetArgv aren't mentioned in iOS docs
 302 // and use underscores in their names - they're most probably
 303 // are considered private and therefore should be avoided
 304 // Here is another way to get arguments using Objective C
 305 // runtime
 306 //
 307 // In general it looks like:
 308 // res = Vec::new()
 309 // let args = [[NSProcessInfo processInfo] arguments]
 310 // for i in (0..[args count])
 311 //      res.push([args objectAtIndex:i])
 312 // res
 313 #[cfg(target_os = "ios")]
 314 pub fn args() -> Args {
 315     use mem;
 316
 317     #[link(name = "objc")]
 318     extern {
 319         fn sel_registerName(name: *const libc::c_uchar) -> Sel;
 320         fn objc_msgSend(obj: NsId, sel: Sel, ...) -> NsId;
 321         fn objc_getClass(class_name: *const libc::c_uchar) -> NsId;
 322     }
 323
 324     #[link(name = "Foundation", kind = "framework")]
 325     extern {}
 326
 327     type Sel = *const libc::c_void;
 328     type NsId = *const libc::c_void;
 329
 330     let mut res = Vec::new();
 331
 332     unsafe {
 333         let process_info_sel = sel_registerName("processInfo\0".as_ptr());
 334         let arguments_sel = sel_registerName("arguments\0".as_ptr());
 335         let utf8_sel = sel_registerName("UTF8String\0".as_ptr());
 336         let count_sel = sel_registerName("count\0".as_ptr());
 337         let object_at_sel = sel_registerName("objectAtIndex:\0".as_ptr());
 338
 339         let klass = objc_getClass("NSProcessInfo\0".as_ptr());
 340         let info = objc_msgSend(klass, process_info_sel);
 341         let args = objc_msgSend(info, arguments_sel);
 342
 343         let cnt: usize = mem::transmute(objc_msgSend(args, count_sel));
 344         for i in (0..cnt) {
 345             let tmp = objc_msgSend(args, object_at_sel, i);
 346             let utf_c_str: *const libc::c_char =
 347                 mem::transmute(objc_msgSend(tmp, utf8_sel));
 348             let bytes = CStr::from_ptr(utf_c_str).to_bytes();
 349             res.push(OsString::from(str::from_utf8(bytes).unwrap()))
 350         }
 351     }
 352
 353     Args { iter: res.into_iter(), _dont_send_or_sync_me: 0 as *mut _ }
 354 }
 355
 356 #[cfg(any(target_os = "linux",
 357           target_os = "android",
 358           target_os = "freebsd",
 359           target_os = "dragonfly",
 360           target_os = "bitrig",
 361           target_os = "openbsd"))]
 362 pub fn args() -> Args {
 363     use rt;
 364     let bytes = rt::args::clone().unwrap_or(Vec::new());
 365     let v: Vec<OsString> = bytes.into_iter().map(|v| {
 366         OsStringExt::from_vec(v)
 367     }).collect();
 368     Args { iter: v.into_iter(), _dont_send_or_sync_me: 0 as *mut _ }
 369 }
 370
 371 pub struct Env {
 372     iter: vec::IntoIter<(OsString, OsString)>,
 373     _dont_send_or_sync_me: *mut (),
 374 }
 375
 376 impl Iterator for Env {
 377     type Item = (OsString, OsString);
 378     fn next(&mut self) -> Option<(OsString, OsString)> { self.iter.next() }
 379     fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
 380 }
 381
 382 #[cfg(target_os = "macos")]
 383 pub unsafe fn environ() -> *mut *const *const c_char {
 384     extern { fn _NSGetEnviron() -> *mut *const *const c_char; }
 385     _NSGetEnviron()
 386 }
 387
 388 #[cfg(not(target_os = "macos"))]
 389 pub unsafe fn environ() -> *mut *const *const c_char {
 390     extern { static mut environ: *const *const c_char; }
 391     &mut environ
 392 }
 393
 394 /// Returns a vector of (variable, value) byte-vector pairs for all the
 395 /// environment variables of the current process.
 396 pub fn env() -> Env {
 397     return unsafe {
 398         let mut environ = *environ();
 399         if environ as usize == 0 {
 400             panic!("os::env() failure getting env string from OS: {}",
 401                    io::Error::last_os_error());
 402         }
 403         let mut result = Vec::new();
 404         while *environ != ptr::null() {
 405             result.push(parse(CStr::from_ptr(*environ).to_bytes()));
 406             environ = environ.offset(1);
 407         }
 408         Env { iter: result.into_iter(), _dont_send_or_sync_me: 0 as *mut _ }
 409     };
 410
 411     fn parse(input: &[u8]) -> (OsString, OsString) {
 412         let mut it = input.splitn(2, |b| *b == b'=');
 413         let key = it.next().unwrap().to_vec();
 414         let default: &[u8] = &[];
 415         let val = it.next().unwrap_or(default).to_vec();
 416         (OsStringExt::from_vec(key), OsStringExt::from_vec(val))
 417     }
 418 }
 419
 420 pub fn getenv(k: &OsStr) -> Option<OsString> {
 421     unsafe {
 422         let s = k.to_cstring().unwrap();
 423         let s = libc::getenv(s.as_ptr()) as *const _;
 424         if s.is_null() {
 425             None
 426         } else {
 427             Some(OsStringExt::from_vec(CStr::from_ptr(s).to_bytes().to_vec()))
 428         }
 429     }
 430 }
 431
 432 pub fn setenv(k: &OsStr, v: &OsStr) {
 433     unsafe {
 434         let k = k.to_cstring().unwrap();
 435         let v = v.to_cstring().unwrap();
 436         if libc::funcs::posix01::unistd::setenv(k.as_ptr(), v.as_ptr(), 1) != 0 {
 437             panic!("failed setenv: {}", io::Error::last_os_error());
 438         }
 439     }
 440 }
 441
 442 pub fn unsetenv(n: &OsStr) {
 443     unsafe {
 444         let nbuf = n.to_cstring().unwrap();
 445         if libc::funcs::posix01::unistd::unsetenv(nbuf.as_ptr()) != 0 {
 446             panic!("failed unsetenv: {}", io::Error::last_os_error());
 447         }
 448     }
 449 }
 450
 451 #[allow(deprecated)]
 452 pub unsafe fn pipe() -> IoResult<(FileDesc, FileDesc)> {
 453     let mut fds = [0; 2];
 454     if libc::pipe(fds.as_mut_ptr()) == 0 {
 455         Ok((FileDesc::new(fds[0], true), FileDesc::new(fds[1], true)))
 456     } else {
 457         Err(IoError::last_error())
 458     }
 459 }
 460
 461 pub fn page_size() -> usize {
 462     unsafe {
 463         libc::sysconf(libc::_SC_PAGESIZE) as usize
 464     }
 465 }
 466
 467 pub fn temp_dir() -> PathBuf {
 468     getenv("TMPDIR".as_ref()).map(os2path).unwrap_or_else(|| {
 469         if cfg!(target_os = "android") {
 470             PathBuf::from("/data/local/tmp")
 471         } else {
 472             PathBuf::from("/tmp")
 473         }
 474     })
 475 }
 476
 477 pub fn home_dir() -> Option<PathBuf> {
 478     return getenv("HOME".as_ref()).or_else(|| unsafe {
 479         fallback()
 480     }).map(os2path);
 481
 482     #[cfg(any(target_os = "android",
 483               target_os = "ios"))]
 484     unsafe fn fallback() -> Option<OsString> { None }
 485     #[cfg(not(any(target_os = "android",
 486                   target_os = "ios")))]
 487     unsafe fn fallback() -> Option<OsString> {
 488         let amt = match libc::sysconf(c::_SC_GETPW_R_SIZE_MAX) {
 489             n if n < 0 => 512 as usize,
 490             n => n as usize,
 491         };
 492         let me = libc::getuid();
 493         loop {
 494             let mut buf = Vec::with_capacity(amt);
 495             let mut passwd: c::passwd = mem::zeroed();
 496             let mut result = 0 as *mut _;
 497             match c::getpwuid_r(me, &mut passwd, buf.as_mut_ptr(),
 498                                 buf.capacity() as libc::size_t,
 499                                 &mut result) {
 500                 0 if !result.is_null() => {}
 501                 _ => return None
 502             }
 503             let ptr = passwd.pw_dir as *const _;
 504             let bytes = CStr::from_ptr(ptr).to_bytes().to_vec();
 505             return Some(OsStringExt::from_vec(bytes))
 506         }
 507     }
 508 }
 509
 510 pub fn exit(code: i32) -> ! {
 511     unsafe { libc::exit(code as c_int) }
 512 }