src/librustc_back/fs.rs

   1 // Copyright 2014 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 use std::io;
  12 use std::path::{Path, PathBuf};
  13
  14 #[cfg(windows)]
  15 pub fn realpath(original: &Path) -> io::Result<PathBuf> {
  16     Ok(original.to_path_buf())
  17 }
  18
  19 #[cfg(unix)]
  20 pub fn realpath(original: &Path) -> io::Result<PathBuf> {
  21     use libc;
  22     use std::ffi::{OsString, CString};
  23     use std::os::unix::prelude::*;
  24
  25     extern {
  26         fn realpath(pathname: *const libc::c_char, resolved: *mut libc::c_char)
  27                     -> *mut libc::c_char;
  28     }
  29
  30     let path = try!(CString::new(original.as_os_str().as_bytes()));
  31     let mut buf = vec![0u8; 16 * 1024];
  32     unsafe {
  33         let r = realpath(path.as_ptr(), buf.as_mut_ptr() as *mut _);
  34         if r.is_null() {
  35             return Err(io::Error::last_os_error())
  36         }
  37     }
  38     let p = buf.iter().position(|i| *i == 0).unwrap();
  39     buf.truncate(p);
  40     Ok(PathBuf::from(OsString::from_vec(buf)))
  41 }
  42
  43 #[cfg(all(not(windows), test))]
  44 mod test {
  45     use tempdir::TempDir;
  46     use std::fs::{self, File};
  47     use super::realpath;
  48
  49     #[test]
  50     fn realpath_works() {
  51         let tmpdir = TempDir::new("rustc-fs").unwrap();
  52         let tmpdir = realpath(tmpdir.path()).unwrap();
  53         let file = tmpdir.join("test");
  54         let dir = tmpdir.join("test2");
  55         let link = dir.join("link");
  56         let linkdir = tmpdir.join("test3");
  57
  58         File::create(&file).unwrap();
  59         fs::create_dir(&dir).unwrap();
  60         fs::soft_link(&file, &link).unwrap();
  61         fs::soft_link(&dir, &linkdir).unwrap();
  62
  63         assert_eq!(realpath(&tmpdir).unwrap(), tmpdir);
  64         assert_eq!(realpath(&file).unwrap(), file);
  65         assert_eq!(realpath(&link).unwrap(), file);
  66         assert_eq!(realpath(&linkdir).unwrap(), dir);
  67         assert_eq!(realpath(&linkdir.join("link")).unwrap(), file);
  68     }
  69
  70     #[test]
  71     fn realpath_works_tricky() {
  72         let tmpdir = TempDir::new("rustc-fs").unwrap();
  73         let tmpdir = realpath(tmpdir.path()).unwrap();
  74
  75         let a = tmpdir.join("a");
  76         let b = a.join("b");
  77         let c = b.join("c");
  78         let d = a.join("d");
  79         let e = d.join("e");
  80         let f = a.join("f");
  81
  82         fs::create_dir_all(&b).unwrap();
  83         fs::create_dir_all(&d).unwrap();
  84         File::create(&f).unwrap();
  85         fs::soft_link("../d/e", &c).unwrap();
  86         fs::soft_link("../f", &e).unwrap();
  87
  88         assert_eq!(realpath(&c).unwrap(), f);
  89         assert_eq!(realpath(&e).unwrap(), f);
  90     }
  91 }