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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
commit | 43a97878ce14b72f0981164f87f2e35e14151312 (patch) | |
tree | 620249daf56c0258faa40cbdcf9cfba06de2a846 /third_party/rust/tempfile/src/file | |
parent | Initial commit. (diff) | |
download | firefox-upstream.tar.xz firefox-upstream.zip |
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/tempfile/src/file')
-rw-r--r-- | third_party/rust/tempfile/src/file/imp/mod.rs | 12 | ||||
-rw-r--r-- | third_party/rust/tempfile/src/file/imp/other.rs | 30 | ||||
-rw-r--r-- | third_party/rust/tempfile/src/file/imp/unix.rs | 156 | ||||
-rw-r--r-- | third_party/rust/tempfile/src/file/imp/windows.rs | 108 | ||||
-rw-r--r-- | third_party/rust/tempfile/src/file/mod.rs | 973 |
5 files changed, 1279 insertions, 0 deletions
diff --git a/third_party/rust/tempfile/src/file/imp/mod.rs b/third_party/rust/tempfile/src/file/imp/mod.rs new file mode 100644 index 0000000000..fbb2bbf635 --- /dev/null +++ b/third_party/rust/tempfile/src/file/imp/mod.rs @@ -0,0 +1,12 @@ +cfg_if::cfg_if! { + if #[cfg(any(unix, target_os = "redox", target_os = "wasi"))] { + mod unix; + pub use self::unix::*; + } else if #[cfg(windows)] { + mod windows; + pub use self::windows::*; + } else { + mod other; + pub use self::other::*; + } +} diff --git a/third_party/rust/tempfile/src/file/imp/other.rs b/third_party/rust/tempfile/src/file/imp/other.rs new file mode 100644 index 0000000000..d8a55a7458 --- /dev/null +++ b/third_party/rust/tempfile/src/file/imp/other.rs @@ -0,0 +1,30 @@ +use std::fs::{File, OpenOptions}; +use std::io; +use std::path::Path; + +fn not_supported<T>() -> io::Result<T> { + Err(io::Error::new( + io::ErrorKind::Other, + "operation not supported on this platform", + )) +} + +pub fn create_named(_path: &Path, open_options: &mut OpenOptions) -> io::Result<File> { + not_supported() +} + +pub fn create(_dir: &Path) -> io::Result<File> { + not_supported() +} + +pub fn reopen(_file: &File, _path: &Path) -> io::Result<File> { + not_supported() +} + +pub fn persist(_old_path: &Path, _new_path: &Path, _overwrite: bool) -> io::Result<()> { + not_supported() +} + +pub fn keep(path: &Path) -> io::Result<()> { + not_supported() +} diff --git a/third_party/rust/tempfile/src/file/imp/unix.rs b/third_party/rust/tempfile/src/file/imp/unix.rs new file mode 100644 index 0000000000..480743cf79 --- /dev/null +++ b/third_party/rust/tempfile/src/file/imp/unix.rs @@ -0,0 +1,156 @@ +use std::env; +use std::ffi::{CString, OsStr}; +use std::fs::{self, File, OpenOptions}; +use std::io; +cfg_if::cfg_if! { + if #[cfg(not(target_os = "wasi"))] { + use std::os::unix::ffi::OsStrExt; + use std::os::unix::fs::{MetadataExt, OpenOptionsExt}; + } else { + use std::os::wasi::ffi::OsStrExt; + #[cfg(feature = "nightly")] + use std::os::wasi::fs::MetadataExt; + } +} +use crate::util; +use std::path::Path; + +#[cfg(not(target_os = "redox"))] +use libc::{c_char, c_int, link, rename, unlink}; + +#[cfg(not(target_os = "redox"))] +#[inline(always)] +pub fn cvt_err(result: c_int) -> io::Result<c_int> { + if result == -1 { + Err(io::Error::last_os_error()) + } else { + Ok(result) + } +} + +#[cfg(target_os = "redox")] +#[inline(always)] +pub fn cvt_err(result: Result<usize, syscall::Error>) -> io::Result<usize> { + result.map_err(|err| io::Error::from_raw_os_error(err.errno)) +} + +// Stolen from std. +pub fn cstr(path: &Path) -> io::Result<CString> { + CString::new(path.as_os_str().as_bytes()) + .map_err(|_| io::Error::new(io::ErrorKind::InvalidInput, "path contained a null")) +} + +pub fn create_named(path: &Path, open_options: &mut OpenOptions) -> io::Result<File> { + open_options.read(true).write(true).create_new(true); + + #[cfg(not(target_os = "wasi"))] + { + open_options.mode(0o600); + } + + open_options.open(path) +} + +fn create_unlinked(path: &Path) -> io::Result<File> { + let tmp; + // shadow this to decrease the lifetime. It can't live longer than `tmp`. + let mut path = path; + if !path.is_absolute() { + let cur_dir = env::current_dir()?; + tmp = cur_dir.join(path); + path = &tmp; + } + + let f = create_named(path, &mut OpenOptions::new())?; + // don't care whether the path has already been unlinked, + // but perhaps there are some IO error conditions we should send up? + let _ = fs::remove_file(path); + Ok(f) +} + +#[cfg(target_os = "linux")] +pub fn create(dir: &Path) -> io::Result<File> { + use libc::{EISDIR, ENOENT, EOPNOTSUPP, O_TMPFILE}; + OpenOptions::new() + .read(true) + .write(true) + .custom_flags(O_TMPFILE) // do not mix with `create_new(true)` + .open(dir) + .or_else(|e| { + match e.raw_os_error() { + // These are the three "not supported" error codes for O_TMPFILE. + Some(EOPNOTSUPP) | Some(EISDIR) | Some(ENOENT) => create_unix(dir), + _ => Err(e), + } + }) +} + +#[cfg(not(target_os = "linux"))] +pub fn create(dir: &Path) -> io::Result<File> { + create_unix(dir) +} + +fn create_unix(dir: &Path) -> io::Result<File> { + util::create_helper( + dir, + OsStr::new(".tmp"), + OsStr::new(""), + crate::NUM_RAND_CHARS, + |path| create_unlinked(&path), + ) +} + +#[cfg(any(not(target_os = "wasi"), feature = "nightly"))] +pub fn reopen(file: &File, path: &Path) -> io::Result<File> { + let new_file = OpenOptions::new().read(true).write(true).open(path)?; + let old_meta = file.metadata()?; + let new_meta = new_file.metadata()?; + if old_meta.dev() != new_meta.dev() || old_meta.ino() != new_meta.ino() { + return Err(io::Error::new( + io::ErrorKind::NotFound, + "original tempfile has been replaced", + )); + } + Ok(new_file) +} + +#[cfg(all(target_os = "wasi", not(feature = "nightly")))] +pub fn reopen(_file: &File, _path: &Path) -> io::Result<File> { + return Err(io::Error::new( + io::ErrorKind::Other, + "this operation is supported on WASI only on nightly Rust (with `nightly` feature enabled)", + )); +} + +#[cfg(not(target_os = "redox"))] +pub fn persist(old_path: &Path, new_path: &Path, overwrite: bool) -> io::Result<()> { + unsafe { + let old_path = cstr(old_path)?; + let new_path = cstr(new_path)?; + if overwrite { + cvt_err(rename( + old_path.as_ptr() as *const c_char, + new_path.as_ptr() as *const c_char, + ))?; + } else { + cvt_err(link( + old_path.as_ptr() as *const c_char, + new_path.as_ptr() as *const c_char, + ))?; + // Ignore unlink errors. Can we do better? + // On recent linux, we can use renameat2 to do this atomically. + let _ = unlink(old_path.as_ptr() as *const c_char); + } + Ok(()) + } +} + +#[cfg(target_os = "redox")] +pub fn persist(old_path: &Path, new_path: &Path, overwrite: bool) -> io::Result<()> { + // XXX implement when possible + Err(io::Error::from_raw_os_error(syscall::ENOSYS)) +} + +pub fn keep(_: &Path) -> io::Result<()> { + Ok(()) +} diff --git a/third_party/rust/tempfile/src/file/imp/windows.rs b/third_party/rust/tempfile/src/file/imp/windows.rs new file mode 100644 index 0000000000..71b4748802 --- /dev/null +++ b/third_party/rust/tempfile/src/file/imp/windows.rs @@ -0,0 +1,108 @@ +use std::ffi::OsStr; +use std::fs::{File, OpenOptions}; +use std::os::windows::ffi::OsStrExt; +use std::os::windows::fs::OpenOptionsExt; +use std::os::windows::io::{AsRawHandle, FromRawHandle, RawHandle}; +use std::path::Path; +use std::{io, iter}; + +use winapi::um::fileapi::SetFileAttributesW; +use winapi::um::handleapi::INVALID_HANDLE_VALUE; +use winapi::um::winbase::{MoveFileExW, ReOpenFile}; +use winapi::um::winbase::{FILE_FLAG_DELETE_ON_CLOSE, MOVEFILE_REPLACE_EXISTING}; +use winapi::um::winnt::{FILE_ATTRIBUTE_NORMAL, FILE_ATTRIBUTE_TEMPORARY}; +use winapi::um::winnt::{FILE_GENERIC_READ, FILE_GENERIC_WRITE, HANDLE}; +use winapi::um::winnt::{FILE_SHARE_DELETE, FILE_SHARE_READ, FILE_SHARE_WRITE}; + +use crate::util; + +fn to_utf16(s: &Path) -> Vec<u16> { + s.as_os_str().encode_wide().chain(iter::once(0)).collect() +} + +pub fn create_named(path: &Path, open_options: &mut OpenOptions) -> io::Result<File> { + open_options + .create_new(true) + .read(true) + .write(true) + .custom_flags(FILE_ATTRIBUTE_TEMPORARY) + .open(path) +} + +pub fn create(dir: &Path) -> io::Result<File> { + util::create_helper( + dir, + OsStr::new(".tmp"), + OsStr::new(""), + crate::NUM_RAND_CHARS, + |path| { + OpenOptions::new() + .create_new(true) + .read(true) + .write(true) + .share_mode(0) + .custom_flags(FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_DELETE_ON_CLOSE) + .open(path) + }, + ) +} + +pub fn reopen(file: &File, _path: &Path) -> io::Result<File> { + let handle = file.as_raw_handle(); + unsafe { + let handle = ReOpenFile( + handle as HANDLE, + FILE_GENERIC_READ | FILE_GENERIC_WRITE, + FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE, + 0, + ); + if handle == INVALID_HANDLE_VALUE { + Err(io::Error::last_os_error()) + } else { + Ok(FromRawHandle::from_raw_handle(handle as RawHandle)) + } + } +} + +pub fn keep(path: &Path) -> io::Result<()> { + unsafe { + let path_w = to_utf16(path); + if SetFileAttributesW(path_w.as_ptr(), FILE_ATTRIBUTE_NORMAL) == 0 { + Err(io::Error::last_os_error()) + } else { + Ok(()) + } + } +} + +pub fn persist(old_path: &Path, new_path: &Path, overwrite: bool) -> io::Result<()> { + // TODO: We should probably do this in one-shot using SetFileInformationByHandle but the API is + // really painful. + + unsafe { + let old_path_w = to_utf16(old_path); + let new_path_w = to_utf16(new_path); + + // Don't succeed if this fails. We don't want to claim to have successfully persisted a file + // still marked as temporary because this file won't have the same consistency guarantees. + if SetFileAttributesW(old_path_w.as_ptr(), FILE_ATTRIBUTE_NORMAL) == 0 { + return Err(io::Error::last_os_error()); + } + + let mut flags = 0; + + if overwrite { + flags |= MOVEFILE_REPLACE_EXISTING; + } + + if MoveFileExW(old_path_w.as_ptr(), new_path_w.as_ptr(), flags) == 0 { + let e = io::Error::last_os_error(); + // If this fails, the temporary file is now un-hidden and no longer marked temporary + // (slightly less efficient) but it will still work. + let _ = SetFileAttributesW(old_path_w.as_ptr(), FILE_ATTRIBUTE_TEMPORARY); + Err(e) + } else { + Ok(()) + } + } +} diff --git a/third_party/rust/tempfile/src/file/mod.rs b/third_party/rust/tempfile/src/file/mod.rs new file mode 100644 index 0000000000..b859ced792 --- /dev/null +++ b/third_party/rust/tempfile/src/file/mod.rs @@ -0,0 +1,973 @@ +use std::env; +use std::error; +use std::ffi::OsStr; +use std::fmt; +use std::fs::{self, File, OpenOptions}; +use std::io::{self, Read, Seek, SeekFrom, Write}; +use std::mem; +use std::ops::Deref; +use std::path::{Path, PathBuf}; + +use crate::error::IoResultExt; +use crate::Builder; + +mod imp; + +/// Create a new temporary file. +/// +/// The file will be created in the location returned by [`std::env::temp_dir()`]. +/// +/// # Security +/// +/// This variant is secure/reliable in the presence of a pathological temporary file cleaner. +/// +/// # Resource Leaking +/// +/// The temporary file will be automatically removed by the OS when the last handle to it is closed. +/// This doesn't rely on Rust destructors being run, so will (almost) never fail to clean up the temporary file. +/// +/// # Errors +/// +/// If the file can not be created, `Err` is returned. +/// +/// # Examples +/// +/// ``` +/// use tempfile::tempfile; +/// use std::io::{self, Write}; +/// +/// # fn main() { +/// # if let Err(_) = run() { +/// # ::std::process::exit(1); +/// # } +/// # } +/// # fn run() -> Result<(), io::Error> { +/// // Create a file inside of `std::env::temp_dir()`. +/// let mut file = tempfile()?; +/// +/// writeln!(file, "Brian was here. Briefly.")?; +/// # Ok(()) +/// # } +/// ``` +/// +/// [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html +pub fn tempfile() -> io::Result<File> { + tempfile_in(&env::temp_dir()) +} + +/// Create a new temporary file in the specified directory. +/// +/// # Security +/// +/// This variant is secure/reliable in the presence of a pathological temporary file cleaner. +/// If the temporary file isn't created in [`std::env::temp_dir()`] then temporary file cleaners aren't an issue. +/// +/// # Resource Leaking +/// +/// The temporary file will be automatically removed by the OS when the last handle to it is closed. +/// This doesn't rely on Rust destructors being run, so will (almost) never fail to clean up the temporary file. +/// +/// # Errors +/// +/// If the file can not be created, `Err` is returned. +/// +/// # Examples +/// +/// ``` +/// use tempfile::tempfile_in; +/// use std::io::{self, Write}; +/// +/// # fn main() { +/// # if let Err(_) = run() { +/// # ::std::process::exit(1); +/// # } +/// # } +/// # fn run() -> Result<(), io::Error> { +/// // Create a file inside of the current working directory +/// let mut file = tempfile_in("./")?; +/// +/// writeln!(file, "Brian was here. Briefly.")?; +/// # Ok(()) +/// # } +/// ``` +/// +/// [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html +pub fn tempfile_in<P: AsRef<Path>>(dir: P) -> io::Result<File> { + imp::create(dir.as_ref()) +} + +/// Error returned when persisting a temporary file path fails. +#[derive(Debug)] +pub struct PathPersistError { + /// The underlying IO error. + pub error: io::Error, + /// The temporary file path that couldn't be persisted. + pub path: TempPath, +} + +impl From<PathPersistError> for io::Error { + #[inline] + fn from(error: PathPersistError) -> io::Error { + error.error + } +} + +impl From<PathPersistError> for TempPath { + #[inline] + fn from(error: PathPersistError) -> TempPath { + error.path + } +} + +impl fmt::Display for PathPersistError { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "failed to persist temporary file path: {}", self.error) + } +} + +impl error::Error for PathPersistError { + fn source(&self) -> Option<&(dyn error::Error + 'static)> { + Some(&self.error) + } +} + +/// A path to a named temporary file without an open file handle. +/// +/// This is useful when the temporary file needs to be used by a child process, +/// for example. +/// +/// When dropped, the temporary file is deleted. +pub struct TempPath { + path: Box<Path>, +} + +impl TempPath { + /// Close and remove the temporary file. + /// + /// Use this if you want to detect errors in deleting the file. + /// + /// # Errors + /// + /// If the file cannot be deleted, `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// // Close the file, but keep the path to it around. + /// let path = file.into_temp_path(); + /// + /// // By closing the `TempPath` explicitly, we can check that it has + /// // been deleted successfully. If we don't close it explicitly, the + /// // file will still be deleted when `file` goes out of scope, but we + /// // won't know whether deleting the file succeeded. + /// path.close()?; + /// # Ok(()) + /// # } + /// ``` + pub fn close(mut self) -> io::Result<()> { + let result = fs::remove_file(&self.path).with_err_path(|| &*self.path); + self.path = PathBuf::new().into_boxed_path(); + mem::forget(self); + result + } + + /// Persist the temporary file at the target path. + /// + /// If a file exists at the target path, persist will atomically replace it. + /// If this method fails, it will return `self` in the resulting + /// [`PathPersistError`]. + /// + /// Note: Temporary files cannot be persisted across filesystems. Also + /// neither the file contents nor the containing directory are + /// synchronized, so the update may not yet have reached the disk when + /// `persist` returns. + /// + /// # Security + /// + /// Only use this method if you're positive that a temporary file cleaner + /// won't have deleted your file. Otherwise, you might end up persisting an + /// attacker controlled file. + /// + /// # Errors + /// + /// If the file cannot be moved to the new location, `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let mut file = NamedTempFile::new()?; + /// writeln!(file, "Brian was here. Briefly.")?; + /// + /// let path = file.into_temp_path(); + /// path.persist("./saved_file.txt")?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`PathPersistError`]: struct.PathPersistError.html + pub fn persist<P: AsRef<Path>>(mut self, new_path: P) -> Result<(), PathPersistError> { + match imp::persist(&self.path, new_path.as_ref(), true) { + Ok(_) => { + // Don't drop `self`. We don't want to try deleting the old + // temporary file path. (It'll fail, but the failure is never + // seen.) + self.path = PathBuf::new().into_boxed_path(); + mem::forget(self); + Ok(()) + } + Err(e) => Err(PathPersistError { + error: e, + path: self, + }), + } + } + + /// Persist the temporary file at the target path if and only if no file exists there. + /// + /// If a file exists at the target path, fail. If this method fails, it will + /// return `self` in the resulting [`PathPersistError`]. + /// + /// Note: Temporary files cannot be persisted across filesystems. Also Note: + /// This method is not atomic. It can leave the original link to the + /// temporary file behind. + /// + /// # Security + /// + /// Only use this method if you're positive that a temporary file cleaner + /// won't have deleted your file. Otherwise, you might end up persisting an + /// attacker controlled file. + /// + /// # Errors + /// + /// If the file cannot be moved to the new location or a file already exists + /// there, `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let mut file = NamedTempFile::new()?; + /// writeln!(file, "Brian was here. Briefly.")?; + /// + /// let path = file.into_temp_path(); + /// path.persist_noclobber("./saved_file.txt")?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`PathPersistError`]: struct.PathPersistError.html + pub fn persist_noclobber<P: AsRef<Path>>( + mut self, + new_path: P, + ) -> Result<(), PathPersistError> { + match imp::persist(&self.path, new_path.as_ref(), false) { + Ok(_) => { + // Don't drop `self`. We don't want to try deleting the old + // temporary file path. (It'll fail, but the failure is never + // seen.) + self.path = PathBuf::new().into_boxed_path(); + mem::forget(self); + Ok(()) + } + Err(e) => Err(PathPersistError { + error: e, + path: self, + }), + } + } + + /// Keep the temporary file from being deleted. This function will turn the + /// temporary file into a non-temporary file without moving it. + /// + /// + /// # Errors + /// + /// On some platforms (e.g., Windows), we need to mark the file as + /// non-temporary. This operation could fail. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let mut file = NamedTempFile::new()?; + /// writeln!(file, "Brian was here. Briefly.")?; + /// + /// let path = file.into_temp_path(); + /// let path = path.keep()?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`PathPersistError`]: struct.PathPersistError.html + pub fn keep(mut self) -> Result<PathBuf, PathPersistError> { + match imp::keep(&self.path) { + Ok(_) => { + // Don't drop `self`. We don't want to try deleting the old + // temporary file path. (It'll fail, but the failure is never + // seen.) + let path = mem::replace(&mut self.path, PathBuf::new().into_boxed_path()); + mem::forget(self); + Ok(path.into()) + } + Err(e) => Err(PathPersistError { + error: e, + path: self, + }), + } + } + + /// Create a new TempPath from an existing path. This can be done even if no + /// file exists at the given path. + /// + /// This is mostly useful for interacting with libraries and external + /// components that provide files to be consumed or expect a path with no + /// existing file to be given. + pub fn from_path(path: impl Into<PathBuf>) -> Self { + Self { + path: path.into().into_boxed_path(), + } + } +} + +impl fmt::Debug for TempPath { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.path.fmt(f) + } +} + +impl Drop for TempPath { + fn drop(&mut self) { + let _ = fs::remove_file(&self.path); + } +} + +impl Deref for TempPath { + type Target = Path; + + fn deref(&self) -> &Path { + &self.path + } +} + +impl AsRef<Path> for TempPath { + fn as_ref(&self) -> &Path { + &self.path + } +} + +impl AsRef<OsStr> for TempPath { + fn as_ref(&self) -> &OsStr { + self.path.as_os_str() + } +} + +/// A named temporary file. +/// +/// The default constructor, [`NamedTempFile::new()`], creates files in +/// the location returned by [`std::env::temp_dir()`], but `NamedTempFile` +/// can be configured to manage a temporary file in any location +/// by constructing with [`NamedTempFile::new_in()`]. +/// +/// # Security +/// +/// Most operating systems employ temporary file cleaners to delete old +/// temporary files. Unfortunately these temporary file cleaners don't always +/// reliably _detect_ whether the temporary file is still being used. +/// +/// Specifically, the following sequence of events can happen: +/// +/// 1. A user creates a temporary file with `NamedTempFile::new()`. +/// 2. Time passes. +/// 3. The temporary file cleaner deletes (unlinks) the temporary file from the +/// filesystem. +/// 4. Some other program creates a new file to replace this deleted temporary +/// file. +/// 5. The user tries to re-open the temporary file (in the same program or in a +/// different program) by path. Unfortunately, they'll end up opening the +/// file created by the other program, not the original file. +/// +/// ## Operating System Specific Concerns +/// +/// The behavior of temporary files and temporary file cleaners differ by +/// operating system. +/// +/// ### Windows +/// +/// On Windows, open files _can't_ be deleted. This removes most of the concerns +/// around temporary file cleaners. +/// +/// Furthermore, temporary files are, by default, created in per-user temporary +/// file directories so only an application running as the same user would be +/// able to interfere (which they could do anyways). However, an application +/// running as the same user can still _accidentally_ re-create deleted +/// temporary files if the number of random bytes in the temporary file name is +/// too small. +/// +/// So, the only real concern on Windows is: +/// +/// 1. Opening a named temporary file in a world-writable directory. +/// 2. Using the `into_temp_path()` and/or `into_parts()` APIs to close the file +/// handle without deleting the underlying file. +/// 3. Continuing to use the file by path. +/// +/// ### UNIX +/// +/// Unlike on Windows, UNIX (and UNIX like) systems allow open files to be +/// "unlinked" (deleted). +/// +/// #### MacOS +/// +/// Like on Windows, temporary files are created in per-user temporary file +/// directories by default so calling `NamedTempFile::new()` should be +/// relatively safe. +/// +/// #### Linux +/// +/// Unfortunately, most _Linux_ distributions don't create per-user temporary +/// file directories. Worse, systemd's tmpfiles daemon (a common temporary file +/// cleaner) will happily remove open temporary files if they haven't been +/// modified within the last 10 days. +/// +/// # Resource Leaking +/// +/// If the program exits before the `NamedTempFile` destructor is +/// run, such as via [`std::process::exit()`], by segfaulting, or by +/// receiving a signal like `SIGINT`, then the temporary file +/// will not be deleted. +/// +/// Use the [`tempfile()`] function unless you absolutely need a named file. +/// +/// [`tempfile()`]: fn.tempfile.html +/// [`NamedTempFile::new()`]: #method.new +/// [`NamedTempFile::new_in()`]: #method.new_in +/// [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html +/// [`std::process::exit()`]: http://doc.rust-lang.org/std/process/fn.exit.html +pub struct NamedTempFile { + path: TempPath, + file: File, +} + +impl fmt::Debug for NamedTempFile { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "NamedTempFile({:?})", self.path) + } +} + +impl AsRef<Path> for NamedTempFile { + #[inline] + fn as_ref(&self) -> &Path { + self.path() + } +} + +/// Error returned when persisting a temporary file fails. +#[derive(Debug)] +pub struct PersistError { + /// The underlying IO error. + pub error: io::Error, + /// The temporary file that couldn't be persisted. + pub file: NamedTempFile, +} + +impl From<PersistError> for io::Error { + #[inline] + fn from(error: PersistError) -> io::Error { + error.error + } +} + +impl From<PersistError> for NamedTempFile { + #[inline] + fn from(error: PersistError) -> NamedTempFile { + error.file + } +} + +impl fmt::Display for PersistError { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "failed to persist temporary file: {}", self.error) + } +} + +impl error::Error for PersistError { + fn source(&self) -> Option<&(dyn error::Error + 'static)> { + Some(&self.error) + } +} + +impl NamedTempFile { + /// Create a new named temporary file. + /// + /// See [`Builder`] for more configuration. + /// + /// # Security + /// + /// This will create a temporary file in the default temporary file + /// directory (platform dependent). This has security implications on many + /// platforms so please read the security section of this type's + /// documentation. + /// + /// Reasons to use this method: + /// + /// 1. The file has a short lifetime and your temporary file cleaner is + /// sane (doesn't delete recently accessed files). + /// + /// 2. You trust every user on your system (i.e. you are the only user). + /// + /// 3. You have disabled your system's temporary file cleaner or verified + /// that your system doesn't have a temporary file cleaner. + /// + /// Reasons not to use this method: + /// + /// 1. You'll fix it later. No you won't. + /// + /// 2. You don't care about the security of the temporary file. If none of + /// the "reasons to use this method" apply, referring to a temporary + /// file by name may allow an attacker to create/overwrite your + /// non-temporary files. There are exceptions but if you don't already + /// know them, don't use this method. + /// + /// # Errors + /// + /// If the file can not be created, `Err` is returned. + /// + /// # Examples + /// + /// Create a named temporary file and write some data to it: + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), ::std::io::Error> { + /// let mut file = NamedTempFile::new()?; + /// + /// writeln!(file, "Brian was here. Briefly.")?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`Builder`]: struct.Builder.html + pub fn new() -> io::Result<NamedTempFile> { + Builder::new().tempfile() + } + + /// Create a new named temporary file in the specified directory. + /// + /// See [`NamedTempFile::new()`] for details. + /// + /// [`NamedTempFile::new()`]: #method.new + pub fn new_in<P: AsRef<Path>>(dir: P) -> io::Result<NamedTempFile> { + Builder::new().tempfile_in(dir) + } + + /// Get the temporary file's path. + /// + /// # Security + /// + /// Referring to a temporary file's path may not be secure in all cases. + /// Please read the security section on the top level documentation of this + /// type for details. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), ::std::io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// println!("{:?}", file.path()); + /// # Ok(()) + /// # } + /// ``` + #[inline] + pub fn path(&self) -> &Path { + &self.path + } + + /// Close and remove the temporary file. + /// + /// Use this if you want to detect errors in deleting the file. + /// + /// # Errors + /// + /// If the file cannot be deleted, `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// // By closing the `NamedTempFile` explicitly, we can check that it has + /// // been deleted successfully. If we don't close it explicitly, + /// // the file will still be deleted when `file` goes out + /// // of scope, but we won't know whether deleting the file + /// // succeeded. + /// file.close()?; + /// # Ok(()) + /// # } + /// ``` + pub fn close(self) -> io::Result<()> { + let NamedTempFile { path, .. } = self; + path.close() + } + + /// Persist the temporary file at the target path. + /// + /// If a file exists at the target path, persist will atomically replace it. + /// If this method fails, it will return `self` in the resulting + /// [`PersistError`]. + /// + /// Note: Temporary files cannot be persisted across filesystems. Also + /// neither the file contents nor the containing directory are + /// synchronized, so the update may not yet have reached the disk when + /// `persist` returns. + /// + /// # Security + /// + /// This method persists the temporary file using its path and may not be + /// secure in the in all cases. Please read the security section on the top + /// level documentation of this type for details. + /// + /// # Errors + /// + /// If the file cannot be moved to the new location, `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// let mut persisted_file = file.persist("./saved_file.txt")?; + /// writeln!(persisted_file, "Brian was here. Briefly.")?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`PersistError`]: struct.PersistError.html + pub fn persist<P: AsRef<Path>>(self, new_path: P) -> Result<File, PersistError> { + let NamedTempFile { path, file } = self; + match path.persist(new_path) { + Ok(_) => Ok(file), + Err(err) => { + let PathPersistError { error, path } = err; + Err(PersistError { + file: NamedTempFile { path, file }, + error, + }) + } + } + } + + /// Persist the temporary file at the target path if and only if no file exists there. + /// + /// If a file exists at the target path, fail. If this method fails, it will + /// return `self` in the resulting PersistError. + /// + /// Note: Temporary files cannot be persisted across filesystems. Also Note: + /// This method is not atomic. It can leave the original link to the + /// temporary file behind. + /// + /// # Security + /// + /// This method persists the temporary file using its path and may not be + /// secure in the in all cases. Please read the security section on the top + /// level documentation of this type for details. + /// + /// # Errors + /// + /// If the file cannot be moved to the new location or a file already exists there, + /// `Err` is returned. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// let mut persisted_file = file.persist_noclobber("./saved_file.txt")?; + /// writeln!(persisted_file, "Brian was here. Briefly.")?; + /// # Ok(()) + /// # } + /// ``` + pub fn persist_noclobber<P: AsRef<Path>>(self, new_path: P) -> Result<File, PersistError> { + let NamedTempFile { path, file } = self; + match path.persist_noclobber(new_path) { + Ok(_) => Ok(file), + Err(err) => { + let PathPersistError { error, path } = err; + Err(PersistError { + file: NamedTempFile { path, file }, + error, + }) + } + } + } + + /// Keep the temporary file from being deleted. This function will turn the + /// temporary file into a non-temporary file without moving it. + /// + /// + /// # Errors + /// + /// On some platforms (e.g., Windows), we need to mark the file as + /// non-temporary. This operation could fail. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io::{self, Write}; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let mut file = NamedTempFile::new()?; + /// writeln!(file, "Brian was here. Briefly.")?; + /// + /// let (file, path) = file.keep()?; + /// # Ok(()) + /// # } + /// ``` + /// + /// [`PathPersistError`]: struct.PathPersistError.html + pub fn keep(self) -> Result<(File, PathBuf), PersistError> { + let (file, path) = (self.file, self.path); + match path.keep() { + Ok(path) => Ok((file, path)), + Err(PathPersistError { error, path }) => Err(PersistError { + file: NamedTempFile { path, file }, + error, + }), + } + } + + /// Securely reopen the temporary file. + /// + /// This function is useful when you need multiple independent handles to + /// the same file. It's perfectly fine to drop the original `NamedTempFile` + /// while holding on to `File`s returned by this function; the `File`s will + /// remain usable. However, they may not be nameable. + /// + /// # Errors + /// + /// If the file cannot be reopened, `Err` is returned. + /// + /// # Security + /// + /// Unlike `File::open(my_temp_file.path())`, `NamedTempFile::reopen()` + /// guarantees that the re-opened file is the _same_ file, even in the + /// presence of pathological temporary file cleaners. + /// + /// # Examples + /// + /// ```no_run + /// # use std::io; + /// use tempfile::NamedTempFile; + /// + /// # fn main() { + /// # if let Err(_) = run() { + /// # ::std::process::exit(1); + /// # } + /// # } + /// # fn run() -> Result<(), io::Error> { + /// let file = NamedTempFile::new()?; + /// + /// let another_handle = file.reopen()?; + /// # Ok(()) + /// # } + /// ``` + pub fn reopen(&self) -> io::Result<File> { + imp::reopen(self.as_file(), NamedTempFile::path(self)) + .with_err_path(|| NamedTempFile::path(self)) + } + + /// Get a reference to the underlying file. + pub fn as_file(&self) -> &File { + &self.file + } + + /// Get a mutable reference to the underlying file. + pub fn as_file_mut(&mut self) -> &mut File { + &mut self.file + } + + /// Convert the temporary file into a `std::fs::File`. + /// + /// The inner file will be deleted. + pub fn into_file(self) -> File { + self.file + } + + /// Closes the file, leaving only the temporary file path. + /// + /// This is useful when another process must be able to open the temporary + /// file. + pub fn into_temp_path(self) -> TempPath { + self.path + } + + /// Converts the named temporary file into its constituent parts. + /// + /// Note: When the path is dropped, the file is deleted but the file handle + /// is still usable. + pub fn into_parts(self) -> (File, TempPath) { + (self.file, self.path) + } +} + +impl Read for NamedTempFile { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.as_file_mut().read(buf).with_err_path(|| self.path()) + } +} + +impl<'a> Read for &'a NamedTempFile { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.as_file().read(buf).with_err_path(|| self.path()) + } +} + +impl Write for NamedTempFile { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.as_file_mut().write(buf).with_err_path(|| self.path()) + } + #[inline] + fn flush(&mut self) -> io::Result<()> { + self.as_file_mut().flush().with_err_path(|| self.path()) + } +} + +impl<'a> Write for &'a NamedTempFile { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.as_file().write(buf).with_err_path(|| self.path()) + } + #[inline] + fn flush(&mut self) -> io::Result<()> { + self.as_file().flush().with_err_path(|| self.path()) + } +} + +impl Seek for NamedTempFile { + fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> { + self.as_file_mut().seek(pos).with_err_path(|| self.path()) + } +} + +impl<'a> Seek for &'a NamedTempFile { + fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> { + self.as_file().seek(pos).with_err_path(|| self.path()) + } +} + +#[cfg(unix)] +impl std::os::unix::io::AsRawFd for NamedTempFile { + #[inline] + fn as_raw_fd(&self) -> std::os::unix::io::RawFd { + self.as_file().as_raw_fd() + } +} + +#[cfg(windows)] +impl std::os::windows::io::AsRawHandle for NamedTempFile { + #[inline] + fn as_raw_handle(&self) -> std::os::windows::io::RawHandle { + self.as_file().as_raw_handle() + } +} + +pub(crate) fn create_named( + mut path: PathBuf, + open_options: &mut OpenOptions, +) -> io::Result<NamedTempFile> { + // Make the path absolute. Otherwise, changing directories could cause us to + // delete the wrong file. + if !path.is_absolute() { + path = env::current_dir()?.join(path) + } + imp::create_named(&path, open_options) + .with_err_path(|| path.clone()) + .map(|file| NamedTempFile { + path: TempPath { + path: path.into_boxed_path(), + }, + file, + }) +} |