Jiyong Park | 7ce5f52 | 2021-11-01 09:47:19 +0900 | [diff] [blame] | 1 | //! Temporary files and directories. |
| 2 | //! |
| 3 | //! - Use the [`tempfile()`] function for temporary files |
| 4 | //! - Use the [`tempdir()`] function for temporary directories. |
| 5 | //! |
| 6 | //! # Design |
| 7 | //! |
| 8 | //! This crate provides several approaches to creating temporary files and directories. |
| 9 | //! [`tempfile()`] relies on the OS to remove the temporary file once the last handle is closed. |
| 10 | //! [`TempDir`] and [`NamedTempFile`] both rely on Rust destructors for cleanup. |
| 11 | //! |
| 12 | //! When choosing between the temporary file variants, prefer `tempfile` |
| 13 | //! unless you either need to know the file's path or to be able to persist it. |
| 14 | //! |
| 15 | //! ## Resource Leaking |
| 16 | //! |
| 17 | //! `tempfile` will (almost) never fail to cleanup temporary resources, but `TempDir` and `NamedTempFile` will if |
| 18 | //! their destructors don't run. This is because `tempfile` relies on the OS to cleanup the |
| 19 | //! underlying file, while `TempDir` and `NamedTempFile` rely on their destructors to do so. |
| 20 | //! |
| 21 | //! ## Security |
| 22 | //! |
| 23 | //! In the presence of pathological temporary file cleaner, relying on file paths is unsafe because |
| 24 | //! a temporary file cleaner could delete the temporary file which an attacker could then replace. |
| 25 | //! |
| 26 | //! `tempfile` doesn't rely on file paths so this isn't an issue. However, `NamedTempFile` does |
| 27 | //! rely on file paths for _some_ operations. See the security documentation on |
| 28 | //! the `NamedTempFile` type for more information. |
| 29 | //! |
| 30 | //! ## Examples |
| 31 | //! |
| 32 | //! Create a temporary file and write some data into it: |
| 33 | //! |
| 34 | //! ``` |
| 35 | //! use tempfile::tempfile; |
| 36 | //! use std::io::{self, Write}; |
| 37 | //! |
| 38 | //! # fn main() { |
| 39 | //! # if let Err(_) = run() { |
| 40 | //! # ::std::process::exit(1); |
| 41 | //! # } |
| 42 | //! # } |
| 43 | //! # fn run() -> Result<(), io::Error> { |
| 44 | //! // Create a file inside of `std::env::temp_dir()`. |
| 45 | //! let mut file = tempfile()?; |
| 46 | //! |
| 47 | //! writeln!(file, "Brian was here. Briefly.")?; |
| 48 | //! # Ok(()) |
| 49 | //! # } |
| 50 | //! ``` |
| 51 | //! |
| 52 | //! Create a named temporary file and open an independent file handle: |
| 53 | //! |
| 54 | //! ``` |
| 55 | //! use tempfile::NamedTempFile; |
| 56 | //! use std::io::{self, Write, Read}; |
| 57 | //! |
| 58 | //! # fn main() { |
| 59 | //! # if let Err(_) = run() { |
| 60 | //! # ::std::process::exit(1); |
| 61 | //! # } |
| 62 | //! # } |
| 63 | //! # fn run() -> Result<(), io::Error> { |
| 64 | //! let text = "Brian was here. Briefly."; |
| 65 | //! |
| 66 | //! // Create a file inside of `std::env::temp_dir()`. |
| 67 | //! let mut file1 = NamedTempFile::new()?; |
| 68 | //! |
| 69 | //! // Re-open it. |
| 70 | //! let mut file2 = file1.reopen()?; |
| 71 | //! |
| 72 | //! // Write some test data to the first handle. |
| 73 | //! file1.write_all(text.as_bytes())?; |
| 74 | //! |
| 75 | //! // Read the test data using the second handle. |
| 76 | //! let mut buf = String::new(); |
| 77 | //! file2.read_to_string(&mut buf)?; |
| 78 | //! assert_eq!(buf, text); |
| 79 | //! # Ok(()) |
| 80 | //! # } |
| 81 | //! ``` |
| 82 | //! |
| 83 | //! Create a temporary directory and add a file to it: |
| 84 | //! |
| 85 | //! ``` |
| 86 | //! use tempfile::tempdir; |
| 87 | //! use std::fs::File; |
| 88 | //! use std::io::{self, Write}; |
| 89 | //! |
| 90 | //! # fn main() { |
| 91 | //! # if let Err(_) = run() { |
| 92 | //! # ::std::process::exit(1); |
| 93 | //! # } |
| 94 | //! # } |
| 95 | //! # fn run() -> Result<(), io::Error> { |
| 96 | //! // Create a directory inside of `std::env::temp_dir()`. |
| 97 | //! let dir = tempdir()?; |
| 98 | //! |
| 99 | //! let file_path = dir.path().join("my-temporary-note.txt"); |
| 100 | //! let mut file = File::create(file_path)?; |
| 101 | //! writeln!(file, "Brian was here. Briefly.")?; |
| 102 | //! |
| 103 | //! // By closing the `TempDir` explicitly, we can check that it has |
| 104 | //! // been deleted successfully. If we don't close it explicitly, |
| 105 | //! // the directory will still be deleted when `dir` goes out |
| 106 | //! // of scope, but we won't know whether deleting the directory |
| 107 | //! // succeeded. |
| 108 | //! drop(file); |
| 109 | //! dir.close()?; |
| 110 | //! # Ok(()) |
| 111 | //! # } |
| 112 | //! ``` |
| 113 | //! |
| 114 | //! [`tempfile()`]: fn.tempfile.html |
| 115 | //! [`tempdir()`]: fn.tempdir.html |
| 116 | //! [`TempDir`]: struct.TempDir.html |
| 117 | //! [`NamedTempFile`]: struct.NamedTempFile.html |
| 118 | //! [`std::env::temp_dir()`]: https://doc.rust-lang.org/std/env/fn.temp_dir.html |
| 119 | |
| 120 | #![doc( |
| 121 | html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png", |
| 122 | html_favicon_url = "https://www.rust-lang.org/favicon.ico", |
| 123 | html_root_url = "https://docs.rs/tempfile/3.1.0" |
| 124 | )] |
| 125 | #![cfg_attr(test, deny(warnings))] |
| 126 | #![deny(rust_2018_idioms)] |
| 127 | #![allow(clippy::redundant_field_names)] |
| 128 | #![cfg_attr(feature = "nightly", feature(wasi_ext))] |
| 129 | |
| 130 | #[macro_use] |
| 131 | extern crate cfg_if; |
| 132 | |
| 133 | #[cfg(doctest)] |
| 134 | #[macro_use] |
| 135 | extern crate doc_comment; |
| 136 | |
| 137 | #[cfg(doctest)] |
| 138 | doctest!("../README.md"); |
| 139 | |
| 140 | const NUM_RETRIES: u32 = 1 << 31; |
| 141 | const NUM_RAND_CHARS: usize = 6; |
| 142 | |
| 143 | use std::ffi::OsStr; |
| 144 | use std::fs::OpenOptions; |
| 145 | use std::path::Path; |
| 146 | use std::{env, io}; |
| 147 | |
| 148 | mod dir; |
| 149 | mod error; |
| 150 | mod file; |
| 151 | mod spooled; |
| 152 | mod util; |
| 153 | |
| 154 | pub use crate::dir::{tempdir, tempdir_in, TempDir}; |
| 155 | pub use crate::file::{ |
| 156 | tempfile, tempfile_in, NamedTempFile, PathPersistError, PersistError, TempPath, |
| 157 | }; |
| 158 | pub use crate::spooled::{spooled_tempfile, SpooledTempFile}; |
| 159 | |
| 160 | /// Create a new temporary file or directory with custom parameters. |
| 161 | #[derive(Debug, Clone, Eq, PartialEq)] |
| 162 | pub struct Builder<'a, 'b> { |
| 163 | random_len: usize, |
| 164 | prefix: &'a OsStr, |
| 165 | suffix: &'b OsStr, |
| 166 | append: bool, |
| 167 | } |
| 168 | |
| 169 | impl<'a, 'b> Default for Builder<'a, 'b> { |
| 170 | fn default() -> Self { |
| 171 | Builder { |
| 172 | random_len: crate::NUM_RAND_CHARS, |
| 173 | prefix: OsStr::new(".tmp"), |
| 174 | suffix: OsStr::new(""), |
| 175 | append: false, |
| 176 | } |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | impl<'a, 'b> Builder<'a, 'b> { |
| 181 | /// Create a new `Builder`. |
| 182 | /// |
| 183 | /// # Examples |
| 184 | /// |
| 185 | /// Create a named temporary file and write some data into it: |
| 186 | /// |
| 187 | /// ``` |
| 188 | /// # use std::io; |
| 189 | /// # use std::ffi::OsStr; |
| 190 | /// # fn main() { |
| 191 | /// # if let Err(_) = run() { |
| 192 | /// # ::std::process::exit(1); |
| 193 | /// # } |
| 194 | /// # } |
| 195 | /// # fn run() -> Result<(), io::Error> { |
| 196 | /// use tempfile::Builder; |
| 197 | /// |
| 198 | /// let named_tempfile = Builder::new() |
| 199 | /// .prefix("my-temporary-note") |
| 200 | /// .suffix(".txt") |
| 201 | /// .rand_bytes(5) |
| 202 | /// .tempfile()?; |
| 203 | /// |
| 204 | /// let name = named_tempfile |
| 205 | /// .path() |
| 206 | /// .file_name().and_then(OsStr::to_str); |
| 207 | /// |
| 208 | /// if let Some(name) = name { |
| 209 | /// assert!(name.starts_with("my-temporary-note")); |
| 210 | /// assert!(name.ends_with(".txt")); |
| 211 | /// assert_eq!(name.len(), "my-temporary-note.txt".len() + 5); |
| 212 | /// } |
| 213 | /// # Ok(()) |
| 214 | /// # } |
| 215 | /// ``` |
| 216 | /// |
| 217 | /// Create a temporary directory and add a file to it: |
| 218 | /// |
| 219 | /// ``` |
| 220 | /// # use std::io::{self, Write}; |
| 221 | /// # use std::fs::File; |
| 222 | /// # use std::ffi::OsStr; |
| 223 | /// # fn main() { |
| 224 | /// # if let Err(_) = run() { |
| 225 | /// # ::std::process::exit(1); |
| 226 | /// # } |
| 227 | /// # } |
| 228 | /// # fn run() -> Result<(), io::Error> { |
| 229 | /// use tempfile::Builder; |
| 230 | /// |
| 231 | /// let dir = Builder::new() |
| 232 | /// .prefix("my-temporary-dir") |
| 233 | /// .rand_bytes(5) |
| 234 | /// .tempdir()?; |
| 235 | /// |
| 236 | /// let file_path = dir.path().join("my-temporary-note.txt"); |
| 237 | /// let mut file = File::create(file_path)?; |
| 238 | /// writeln!(file, "Brian was here. Briefly.")?; |
| 239 | /// |
| 240 | /// // By closing the `TempDir` explicitly, we can check that it has |
| 241 | /// // been deleted successfully. If we don't close it explicitly, |
| 242 | /// // the directory will still be deleted when `dir` goes out |
| 243 | /// // of scope, but we won't know whether deleting the directory |
| 244 | /// // succeeded. |
| 245 | /// drop(file); |
| 246 | /// dir.close()?; |
| 247 | /// # Ok(()) |
| 248 | /// # } |
| 249 | /// ``` |
| 250 | pub fn new() -> Self { |
| 251 | Self::default() |
| 252 | } |
| 253 | |
| 254 | /// Set a custom filename prefix. |
| 255 | /// |
| 256 | /// Path separators are legal but not advisable. |
| 257 | /// Default: `.tmp`. |
| 258 | /// |
| 259 | /// # Examples |
| 260 | /// |
| 261 | /// ``` |
| 262 | /// # use std::io; |
| 263 | /// # fn main() { |
| 264 | /// # if let Err(_) = run() { |
| 265 | /// # ::std::process::exit(1); |
| 266 | /// # } |
| 267 | /// # } |
| 268 | /// # fn run() -> Result<(), io::Error> { |
| 269 | /// # use tempfile::Builder; |
| 270 | /// let named_tempfile = Builder::new() |
| 271 | /// .prefix("my-temporary-note") |
| 272 | /// .tempfile()?; |
| 273 | /// # Ok(()) |
| 274 | /// # } |
| 275 | /// ``` |
| 276 | pub fn prefix<S: AsRef<OsStr> + ?Sized>(&mut self, prefix: &'a S) -> &mut Self { |
| 277 | self.prefix = prefix.as_ref(); |
| 278 | self |
| 279 | } |
| 280 | |
| 281 | /// Set a custom filename suffix. |
| 282 | /// |
| 283 | /// Path separators are legal but not advisable. |
| 284 | /// Default: empty. |
| 285 | /// |
| 286 | /// # Examples |
| 287 | /// |
| 288 | /// ``` |
| 289 | /// # use std::io; |
| 290 | /// # fn main() { |
| 291 | /// # if let Err(_) = run() { |
| 292 | /// # ::std::process::exit(1); |
| 293 | /// # } |
| 294 | /// # } |
| 295 | /// # fn run() -> Result<(), io::Error> { |
| 296 | /// # use tempfile::Builder; |
| 297 | /// let named_tempfile = Builder::new() |
| 298 | /// .suffix(".txt") |
| 299 | /// .tempfile()?; |
| 300 | /// # Ok(()) |
| 301 | /// # } |
| 302 | /// ``` |
| 303 | pub fn suffix<S: AsRef<OsStr> + ?Sized>(&mut self, suffix: &'b S) -> &mut Self { |
| 304 | self.suffix = suffix.as_ref(); |
| 305 | self |
| 306 | } |
| 307 | |
| 308 | /// Set the number of random bytes. |
| 309 | /// |
| 310 | /// Default: `6`. |
| 311 | /// |
| 312 | /// # Examples |
| 313 | /// |
| 314 | /// ``` |
| 315 | /// # use std::io; |
| 316 | /// # fn main() { |
| 317 | /// # if let Err(_) = run() { |
| 318 | /// # ::std::process::exit(1); |
| 319 | /// # } |
| 320 | /// # } |
| 321 | /// # fn run() -> Result<(), io::Error> { |
| 322 | /// # use tempfile::Builder; |
| 323 | /// let named_tempfile = Builder::new() |
| 324 | /// .rand_bytes(5) |
| 325 | /// .tempfile()?; |
| 326 | /// # Ok(()) |
| 327 | /// # } |
| 328 | /// ``` |
| 329 | pub fn rand_bytes(&mut self, rand: usize) -> &mut Self { |
| 330 | self.random_len = rand; |
| 331 | self |
| 332 | } |
| 333 | |
| 334 | /// Set the file to be opened in append mode. |
| 335 | /// |
| 336 | /// Default: `false`. |
| 337 | /// |
| 338 | /// # Examples |
| 339 | /// |
| 340 | /// ``` |
| 341 | /// # use std::io; |
| 342 | /// # fn main() { |
| 343 | /// # if let Err(_) = run() { |
| 344 | /// # ::std::process::exit(1); |
| 345 | /// # } |
| 346 | /// # } |
| 347 | /// # fn run() -> Result<(), io::Error> { |
| 348 | /// # use tempfile::Builder; |
| 349 | /// let named_tempfile = Builder::new() |
| 350 | /// .append(true) |
| 351 | /// .tempfile()?; |
| 352 | /// # Ok(()) |
| 353 | /// # } |
| 354 | /// ``` |
| 355 | pub fn append(&mut self, append: bool) -> &mut Self { |
| 356 | self.append = append; |
| 357 | self |
| 358 | } |
| 359 | |
| 360 | /// Create the named temporary file. |
| 361 | /// |
| 362 | /// # Security |
| 363 | /// |
| 364 | /// See [the security][security] docs on `NamedTempFile`. |
| 365 | /// |
| 366 | /// # Resource leaking |
| 367 | /// |
| 368 | /// See [the resource leaking][resource-leaking] docs on `NamedTempFile`. |
| 369 | /// |
| 370 | /// # Errors |
| 371 | /// |
| 372 | /// If the file cannot be created, `Err` is returned. |
| 373 | /// |
| 374 | /// # Examples |
| 375 | /// |
| 376 | /// ``` |
| 377 | /// # use std::io; |
| 378 | /// # fn main() { |
| 379 | /// # if let Err(_) = run() { |
| 380 | /// # ::std::process::exit(1); |
| 381 | /// # } |
| 382 | /// # } |
| 383 | /// # fn run() -> Result<(), io::Error> { |
| 384 | /// # use tempfile::Builder; |
| 385 | /// let tempfile = Builder::new().tempfile()?; |
| 386 | /// # Ok(()) |
| 387 | /// # } |
| 388 | /// ``` |
| 389 | /// |
| 390 | /// [security]: struct.NamedTempFile.html#security |
| 391 | /// [resource-leaking]: struct.NamedTempFile.html#resource-leaking |
| 392 | pub fn tempfile(&self) -> io::Result<NamedTempFile> { |
| 393 | self.tempfile_in(&env::temp_dir()) |
| 394 | } |
| 395 | |
| 396 | /// Create the named temporary file in the specified directory. |
| 397 | /// |
| 398 | /// # Security |
| 399 | /// |
| 400 | /// See [the security][security] docs on `NamedTempFile`. |
| 401 | /// |
| 402 | /// # Resource leaking |
| 403 | /// |
| 404 | /// See [the resource leaking][resource-leaking] docs on `NamedTempFile`. |
| 405 | /// |
| 406 | /// # Errors |
| 407 | /// |
| 408 | /// If the file cannot be created, `Err` is returned. |
| 409 | /// |
| 410 | /// # Examples |
| 411 | /// |
| 412 | /// ``` |
| 413 | /// # use std::io; |
| 414 | /// # fn main() { |
| 415 | /// # if let Err(_) = run() { |
| 416 | /// # ::std::process::exit(1); |
| 417 | /// # } |
| 418 | /// # } |
| 419 | /// # fn run() -> Result<(), io::Error> { |
| 420 | /// # use tempfile::Builder; |
| 421 | /// let tempfile = Builder::new().tempfile_in("./")?; |
| 422 | /// # Ok(()) |
| 423 | /// # } |
| 424 | /// ``` |
| 425 | /// |
| 426 | /// [security]: struct.NamedTempFile.html#security |
| 427 | /// [resource-leaking]: struct.NamedTempFile.html#resource-leaking |
| 428 | pub fn tempfile_in<P: AsRef<Path>>(&self, dir: P) -> io::Result<NamedTempFile> { |
| 429 | util::create_helper( |
| 430 | dir.as_ref(), |
| 431 | self.prefix, |
| 432 | self.suffix, |
| 433 | self.random_len, |
| 434 | |path| file::create_named(path, OpenOptions::new().append(self.append)), |
| 435 | ) |
| 436 | } |
| 437 | |
| 438 | /// Attempts to make a temporary directory inside of `env::temp_dir()` whose |
| 439 | /// name will have the prefix, `prefix`. The directory and |
| 440 | /// everything inside it will be automatically deleted once the |
| 441 | /// returned `TempDir` is destroyed. |
| 442 | /// |
| 443 | /// # Resource leaking |
| 444 | /// |
| 445 | /// See [the resource leaking][resource-leaking] docs on `TempDir`. |
| 446 | /// |
| 447 | /// # Errors |
| 448 | /// |
| 449 | /// If the directory can not be created, `Err` is returned. |
| 450 | /// |
| 451 | /// # Examples |
| 452 | /// |
| 453 | /// ``` |
| 454 | /// use std::fs::File; |
| 455 | /// use std::io::Write; |
| 456 | /// use tempfile::Builder; |
| 457 | /// |
| 458 | /// # use std::io; |
| 459 | /// # fn run() -> Result<(), io::Error> { |
| 460 | /// let tmp_dir = Builder::new().tempdir()?; |
| 461 | /// # Ok(()) |
| 462 | /// # } |
| 463 | /// ``` |
| 464 | /// |
| 465 | /// [resource-leaking]: struct.TempDir.html#resource-leaking |
| 466 | pub fn tempdir(&self) -> io::Result<TempDir> { |
| 467 | self.tempdir_in(&env::temp_dir()) |
| 468 | } |
| 469 | |
| 470 | /// Attempts to make a temporary directory inside of `dir`. |
| 471 | /// The directory and everything inside it will be automatically |
| 472 | /// deleted once the returned `TempDir` is destroyed. |
| 473 | /// |
| 474 | /// # Resource leaking |
| 475 | /// |
| 476 | /// See [the resource leaking][resource-leaking] docs on `TempDir`. |
| 477 | /// |
| 478 | /// # Errors |
| 479 | /// |
| 480 | /// If the directory can not be created, `Err` is returned. |
| 481 | /// |
| 482 | /// # Examples |
| 483 | /// |
| 484 | /// ``` |
| 485 | /// use std::fs::{self, File}; |
| 486 | /// use std::io::Write; |
| 487 | /// use tempfile::Builder; |
| 488 | /// |
| 489 | /// # use std::io; |
| 490 | /// # fn run() -> Result<(), io::Error> { |
| 491 | /// let tmp_dir = Builder::new().tempdir_in("./")?; |
| 492 | /// # Ok(()) |
| 493 | /// # } |
| 494 | /// ``` |
| 495 | /// |
| 496 | /// [resource-leaking]: struct.TempDir.html#resource-leaking |
| 497 | pub fn tempdir_in<P: AsRef<Path>>(&self, dir: P) -> io::Result<TempDir> { |
| 498 | let storage; |
| 499 | let mut dir = dir.as_ref(); |
| 500 | if !dir.is_absolute() { |
| 501 | let cur_dir = env::current_dir()?; |
| 502 | storage = cur_dir.join(dir); |
| 503 | dir = &storage; |
| 504 | } |
| 505 | |
| 506 | util::create_helper(dir, self.prefix, self.suffix, self.random_len, dir::create) |
| 507 | } |
| 508 | } |