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