sys_util: Add TempDir class
This will be used to create temporary directories that are lifetime
managed for running jails.
Change-Id: I35dfeae76a211c820db090b65baf72277d9e2d8a
Signed-off-by: Dylan Reid <dgreid@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/520706
Reviewed-by: Zach Reizner <zachr@chromium.org>
diff --git a/sys_util/src/lib.rs b/sys_util/src/lib.rs
index 79a9691..f4bf241 100644
--- a/sys_util/src/lib.rs
+++ b/sys_util/src/lib.rs
@@ -12,6 +12,7 @@
mod guest_address;
mod guest_memory;
mod struct_util;
+mod tempdir;
pub use mmap::*;
pub use eventfd::*;
@@ -20,3 +21,4 @@
pub use guest_address::*;
pub use guest_memory::*;
pub use struct_util::*;
+pub use tempdir::*;
diff --git a/sys_util/src/tempdir.rs b/sys_util/src/tempdir.rs
new file mode 100644
index 0000000..6a27652
--- /dev/null
+++ b/sys_util/src/tempdir.rs
@@ -0,0 +1,100 @@
+// Copyright 2017 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+use std::ffi::CString;
+use std::ffi::OsStr;
+use std::ffi::OsString;
+use std::fs;
+use std::os::unix::ffi::OsStringExt;
+use std::path::Path;
+use std::path::PathBuf;
+
+use libc;
+
+use {Result, errno_result};
+
+/// Create and remove a temporary directory. The directory will be maintained for the lifetime of
+/// the `TempDir` object.
+pub struct TempDir {
+ path: Option<PathBuf>,
+}
+
+impl TempDir {
+ /// Creates a new tempory directory.
+ /// The directory will be removed when the object goes out of scope.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// # use std::path::Path;
+ /// # use std::path::PathBuf;
+ /// # use sys_util::TempDir;
+ /// # fn test_create_temp_dir() -> Result<(), ()> {
+ /// let t = TempDir::new("/tmp/testdir").map_err(|_| ())?;
+ /// assert!(t.as_path().unwrap().exists());
+ /// # Ok(())
+ /// # }
+ /// ```
+ pub fn new<P: AsRef<OsStr>>(prefix: P) -> Result<TempDir> {
+ let mut dir_string = prefix.as_ref().to_os_string();
+ dir_string.push("XXXXXX");
+ // unwrap this result as the internal bytes can't have a null with a valid path.
+ let dir_name = CString::new(dir_string.into_vec()).unwrap();
+ let mut dir_bytes = dir_name.into_bytes_with_nul();
+ let ret = unsafe {
+ // Creating the directory isn't unsafe. The fact that it modifies the guts of the path
+ // is also OK because it only overwrites the last 6 Xs added above.
+ libc::mkdtemp(dir_bytes.as_mut_ptr() as *mut i8)
+ };
+ if ret.is_null() {
+ return errno_result();
+ }
+ dir_bytes.pop(); // Remove the null becasue from_vec can't handle it.
+ Ok(TempDir { path: Some(PathBuf::from(OsString::from_vec(dir_bytes))) })
+ }
+
+ /// Removes the temporary directory. Calling this is optional as dropping a `TempDir` object
+ /// will also remove the directory. Calling remove explicitly allows for better error handling.
+ pub fn remove(mut self) -> Result<()> {
+ let path = self.path.take();
+ path.map_or(Ok(()), |ref p| fs::remove_dir_all(p))?;
+ Ok(())
+ }
+
+ /// Returns the path to the tempdir if it is currently valid
+ pub fn as_path(&self) -> Option<&Path> {
+ self.path.as_ref().map(|ref p| p.as_path())
+ }
+}
+
+impl Drop for TempDir {
+ fn drop(&mut self) {
+ if let Some(ref p) = self.path {
+ // Nothing can be done here if this returns an error.
+ let _ = fs::remove_dir_all(p);
+ }
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn create_dir() {
+ let t = TempDir::new("/tmp/asdf").unwrap();
+ let path = t.as_path().unwrap();
+ assert!(path.exists());
+ assert!(path.is_dir());
+ assert!(path.starts_with("/tmp/"));
+ }
+
+ #[test]
+ fn remove_dir() {
+ let t = TempDir::new("/tmp/asdf").unwrap();
+ let path = t.as_path().unwrap().to_owned();
+ assert!(t.remove().is_ok());
+ assert!(!path.exists());
+ }
+}
