rust/src/librustc_back/tempdir.rs
Jorge Aparicio 0f02309e4b try! -> ?
Automated conversion using the untry tool [1] and the following command:

```
$ find -name '*.rs' -type f | xargs untry
```

at the root of the Rust repo.

[1]: https://github.com/japaric/untry
2016-03-22 22:01:37 -05:00

124 lines
4.5 KiB
Rust

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::env;
use std::io::{self, Error, ErrorKind};
use std::fs;
use std::path::{self, PathBuf, Path};
use std::__rand::{thread_rng, Rng};
/// A wrapper for a path to temporary directory implementing automatic
/// scope-based deletion.
pub struct TempDir {
path: Option<PathBuf>,
}
// How many times should we (re)try finding an unused random name? It should be
// enough that an attacker will run out of luck before we run out of patience.
const NUM_RETRIES: u32 = 1 << 31;
// How many characters should we include in a random file name? It needs to
// be enough to dissuade an attacker from trying to preemptively create names
// of that length, but not so huge that we unnecessarily drain the random number
// generator of entropy.
const NUM_RAND_CHARS: usize = 12;
impl TempDir {
/// Attempts to make a temporary directory inside of `tmpdir` whose name
/// will have the prefix `prefix`. The directory will be automatically
/// deleted once the returned wrapper is destroyed.
///
/// If no directory can be created, `Err` is returned.
#[allow(deprecated)] // rand usage
pub fn new_in<P: AsRef<Path>>(tmpdir: P, prefix: &str)
-> io::Result<TempDir> {
Self::_new_in(tmpdir.as_ref(), prefix)
}
fn _new_in(tmpdir: &Path, prefix: &str) -> io::Result<TempDir> {
let storage;
let mut tmpdir = tmpdir;
if !tmpdir.is_absolute() {
let cur_dir = env::current_dir()?;
storage = cur_dir.join(tmpdir);
tmpdir = &storage;
// return TempDir::new_in(&cur_dir.join(tmpdir), prefix);
}
let mut rng = thread_rng();
for _ in 0..NUM_RETRIES {
let suffix: String = rng.gen_ascii_chars().take(NUM_RAND_CHARS).collect();
let leaf = if !prefix.is_empty() {
format!("{}.{}", prefix, suffix)
} else {
// If we're given an empty string for a prefix, then creating a
// directory starting with "." would lead to it being
// semi-invisible on some systems.
suffix
};
let path = tmpdir.join(&leaf);
match fs::create_dir(&path) {
Ok(_) => return Ok(TempDir { path: Some(path) }),
Err(ref e) if e.kind() == ErrorKind::AlreadyExists => {}
Err(e) => return Err(e)
}
}
Err(Error::new(ErrorKind::AlreadyExists,
"too many temporary directories already exist"))
}
/// Attempts to make a temporary directory inside of `env::temp_dir()` whose
/// name will have the prefix `prefix`. The directory will be automatically
/// deleted once the returned wrapper is destroyed.
///
/// If no directory can be created, `Err` is returned.
pub fn new(prefix: &str) -> io::Result<TempDir> {
TempDir::new_in(&env::temp_dir(), prefix)
}
/// Unwrap the wrapped `std::path::Path` from the `TempDir` wrapper.
/// This discards the wrapper so that the automatic deletion of the
/// temporary directory is prevented.
pub fn into_path(mut self) -> PathBuf {
self.path.take().unwrap()
}
/// Access the wrapped `std::path::Path` to the temporary directory.
pub fn path(&self) -> &path::Path {
self.path.as_ref().unwrap()
}
/// Close and remove the temporary directory
///
/// Although `TempDir` removes the directory on drop, in the destructor
/// any errors are ignored. To detect errors cleaning up the temporary
/// directory, call `close` instead.
pub fn close(mut self) -> io::Result<()> {
self.cleanup_dir()
}
fn cleanup_dir(&mut self) -> io::Result<()> {
match self.path {
Some(ref p) => fs::remove_dir_all(p),
None => Ok(())
}
}
}
impl Drop for TempDir {
fn drop(&mut self) {
let _ = self.cleanup_dir();
}
}
// the tests for this module need to change the path using change_dir,
// and this doesn't play nicely with other tests so these unit tests are located
// in src/test/run-pass/tempfile.rs