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// 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.
#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
html_favicon_url = "https://www.rust-lang.org/favicon.ico",
html_root_url = "https://doc.rust-lang.org/tempdir/")]
#![cfg_attr(test, deny(warnings))]
//! Temporary directories of files.
//!
//! The [`TempDir`] type creates a directory on the file system that
//! is deleted once it goes out of scope. At construction, the
//! `TempDir` creates a new directory with a randomly generated name
//! and a prefix of your choosing.
//!
//! [`TempDir`]: struct.TempDir.html
//! [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html
//!
//! # Examples
//!
//! ```
//! extern crate tempdir;
//!
//! use std::fs::File;
//! use std::io::Write;
//! use tempdir::TempDir;
//!
//! fn main() {
//! // Create a directory inside of `std::env::temp_dir()`, named with
//! // the prefix "example".
//! let tmp_dir = TempDir::new("example").expect("create temp dir");
//! let file_path = tmp_dir.path().join("my-temporary-note.txt");
//! let mut tmp_file = File::create(file_path).expect("create temp file");
//! writeln!(tmp_file, "Brian was here. Briefly.").expect("write temp file");
//!
//! // By closing the `TempDir` explicitly, we can check that it has
//! // been deleted successfully. If we don't close it explicitly,
//! // the directory will still be deleted when `tmp_dir` goes out
//! // of scope, but we won't know whether deleting the directory
//! // succeeded.
//! drop(tmp_file);
//! tmp_dir.close().expect("delete temp dir");
//! }
//! ```
extern crate rand;
use std::env;
use std::io::{self, Error, ErrorKind};
use std::fmt;
use std::fs;
use std::path::{self, PathBuf, Path};
use rand::{thread_rng, Rng};
/// A directory in the filesystem that is automatically deleted when
/// it goes out of scope.
///
/// The [`TempDir`] type creates a directory on the file system that
/// is deleted once it goes out of scope. At construction, the
/// `TempDir` creates a new directory with a randomly generated name,
/// and with a prefix of your choosing.
///
/// The default constructor, [`TempDir::new`], creates directories in
/// the location returned by [`std::env::temp_dir()`], but `TempDir`
/// can be configured to manage a temporary directory in any location
/// by constructing with [`TempDir::new_in`].
///
/// After creating a `TempDir`, work with the file system by doing
/// standard [`std::fs`] file system operations on its [`Path`],
/// which can be retrieved with [`TempDir::path`]. Once the `TempDir`
/// value is dropped, the directory at the path will be deleted, along
/// with any files and directories it contains. It is your responsibility
/// to ensure that no further file system operations are attempted
/// inside the temporary directory once it has been deleted.
///
/// Various platform-specific conditions may cause `TempDir` to fail
/// to delete the underlying directory. It's important to ensure that
/// handles (like [`File`] and [`ReadDir`]) to files inside the
/// directory are dropped before the `TempDir` goes out of scope. The
/// `TempDir` destructor will silently ignore any errors in deleting
/// the directory; to instead handle errors call [`TempDir::close`].
///
/// Note that if the program exits before the `TempDir` destructor is
/// run, such as via [`std::process::exit`], by segfaulting, or by
/// receiving a signal like `SIGINT`, then the temporary directory
/// will not be deleted.
///
/// [`File`]: http://doc.rust-lang.org/std/fs/struct.File.html
/// [`Path`]: http://doc.rust-lang.org/std/path/struct.Path.html
/// [`ReadDir`]: http://doc.rust-lang.org/std/fs/struct.ReadDir.html
/// [`TempDir::close`]: struct.TempDir.html#method.close
/// [`TempDir::new`]: struct.TempDir.html#method.new
/// [`TempDir::new_in`]: struct.TempDir.html#method.new_in
/// [`TempDir::path`]: struct.TempDir.html#method.path
/// [`TempDir`]: struct.TempDir.html
/// [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html
/// [`std::fs`]: http://doc.rust-lang.org/std/fs/index.html
/// [`std::process::exit`]: http://doc.rust-lang.org/std/process/fn.exit.html
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 `env::temp_dir()` whose
/// name will have the prefix, `prefix`. The directory and
/// everything inside it will be automatically deleted once the
/// returned `TempDir` is destroyed.
///
/// # Errors
///
/// If the directory can not be created, `Err` is returned.
///
/// # Examples
///
/// ```
/// use std::fs::File;
/// use std::io::Write;
/// use tempdir::TempDir;
///
/// // Create a directory inside of `std::env::temp_dir()`, named with
/// // the prefix, "example".
/// let tmp_dir = TempDir::new("example").expect("create temp dir");
/// let file_path = tmp_dir.path().join("my-temporary-note.txt");
/// let mut tmp_file = File::create(file_path).expect("create temp file");
/// writeln!(tmp_file, "Brian was here. Briefly.").expect("write temp file");
///
/// // `tmp_dir` goes out of scope, the directory as well as
/// // `tmp_file` will be deleted here.
/// ```
pub fn new(prefix: &str) -> io::Result<TempDir> {
TempDir::new_in(&env::temp_dir(), prefix)
}
/// Attempts to make a temporary directory inside of `tmpdir`
/// whose name will have the prefix `prefix`. The directory and
/// everything inside it will be automatically deleted once the
/// returned `TempDir` is destroyed.
///
/// # Errors
///
/// If the directory can not be created, `Err` is returned.
///
/// # Examples
///
/// ```
/// use std::fs::{self, File};
/// use std::io::Write;
/// use tempdir::TempDir;
///
/// // Create a directory inside of the current directory, named with
/// // the prefix, "example".
/// let tmp_dir = TempDir::new_in(".", "example").expect("create temp dir");
/// let file_path = tmp_dir.path().join("my-temporary-note.txt");
/// let mut tmp_file = File::create(file_path).expect("create temp file");
/// writeln!(tmp_file, "Brian was here. Briefly.").expect("write temp file");
/// ```
pub fn new_in<P: AsRef<Path>>(tmpdir: P, prefix: &str) -> io::Result<TempDir> {
let storage;
let mut tmpdir = tmpdir.as_ref();
if !tmpdir.is_absolute() {
let cur_dir = try!(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.len() > 0 {
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"))
}
/// Accesses the [`Path`] to the temporary directory.
///
/// [`Path`]: http://doc.rust-lang.org/std/path/struct.Path.html
///
/// # Examples
///
/// ```
/// use tempdir::TempDir;
///
/// let tmp_path;
///
/// {
/// let tmp_dir = TempDir::new("example").expect("create temp dir");
/// tmp_path = tmp_dir.path().to_owned();
///
/// // Check that the temp directory actually exists.
/// assert!(tmp_path.exists());
///
/// // End of `tmp_dir` scope, directory will be deleted
/// }
///
/// // Temp directory should be deleted by now
/// assert_eq!(tmp_path.exists(), false);
/// ```
pub fn path(&self) -> &path::Path {
self.path.as_ref().unwrap()
}
/// Unwraps the [`Path`] contained in the `TempDir` and
/// returns it. This destroys the `TempDir` without deleting the
/// directory represented by the returned `Path`.
///
/// [`Path`]: http://doc.rust-lang.org/std/path/struct.Path.html
///
/// # Examples
///
/// ```
/// use std::fs;
/// use tempdir::TempDir;
///
/// let tmp_dir = TempDir::new("example").expect("create temp dir");
///
/// // Convert `tmp_dir` into a `Path`, destroying the `TempDir`
/// // without deleting the directory.
/// let tmp_path = tmp_dir.into_path();
///
/// // Delete the temporary directory ourselves.
/// fs::remove_dir_all(tmp_path).expect("remove temp dir");
/// ```
pub fn into_path(mut self) -> PathBuf {
self.path.take().unwrap()
}
/// Closes and removes the temporary directory, returing a `Result`.
///
/// 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.
///
/// # Errors
///
/// This function may return a variety of [`std::io::Error`]s that result from deleting
/// the files and directories contained with the temporary directory,
/// as well as from deleting the temporary directory itself. These errors
/// may be platform specific.
///
/// [`std::io::Error`]: http://doc.rust-lang.org/std/io/struct.Error.html
///
/// # Examples
///
/// ```
/// use std::fs::File;
/// use std::io::Write;
/// use tempdir::TempDir;
///
/// // Create a directory inside of `std::env::temp_dir()`, named with
/// // the prefix, "example".
/// let tmp_dir = TempDir::new("example").expect("create temp dir");
/// let file_path = tmp_dir.path().join("my-temporary-note.txt");
/// let mut tmp_file = File::create(file_path).expect("create temp file");
/// writeln!(tmp_file, "Brian was here. Briefly.").expect("write temp file");
///
/// // By closing the `TempDir` explicitly we can check that it has
/// // been deleted successfully. If we don't close it explicitly,
/// // the directory will still be deleted when `tmp_dir` goes out
/// // of scope, but we won't know whether deleting the directory
/// // succeeded.
/// drop(tmp_file);
/// tmp_dir.close().expect("delete temp dir");
/// ```
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 AsRef<Path> for TempDir {
fn as_ref(&self) -> &Path {
self.path()
}
}
impl fmt::Debug for TempDir {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("TempDir")
.field("path", &self.path())
.finish()
}
}
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