1 | //===- llvm/Support/FileSystem.h - File System OS Concept -------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file declares the llvm::sys::fs namespace. It is designed after |
10 | // TR2/boost filesystem (v3), but modified to remove exception handling and the |
11 | // path class. |
12 | // |
13 | // All functions return an error_code and their actual work via the last out |
14 | // argument. The out argument is defined if and only if errc::success is |
15 | // returned. A function may return any error code in the generic or system |
16 | // category. However, they shall be equivalent to any error conditions listed |
17 | // in each functions respective documentation if the condition applies. [ note: |
18 | // this does not guarantee that error_code will be in the set of explicitly |
19 | // listed codes, but it does guarantee that if any of the explicitly listed |
20 | // errors occur, the correct error_code will be used ]. All functions may |
21 | // return errc::not_enough_memory if there is not enough memory to complete the |
22 | // operation. |
23 | // |
24 | //===----------------------------------------------------------------------===// |
25 | |
26 | #ifndef LLVM_SUPPORT_FILESYSTEM_H |
27 | #define LLVM_SUPPORT_FILESYSTEM_H |
28 | |
29 | #include "llvm/ADT/SmallString.h" |
30 | #include "llvm/ADT/StringRef.h" |
31 | #include "llvm/ADT/Twine.h" |
32 | #include "llvm/Config/llvm-config.h" |
33 | #include "llvm/Support/Chrono.h" |
34 | #include "llvm/Support/Error.h" |
35 | #include "llvm/Support/ErrorHandling.h" |
36 | #include "llvm/Support/ErrorOr.h" |
37 | #include "llvm/Support/FileSystem/UniqueID.h" |
38 | #include "llvm/Support/MD5.h" |
39 | #include <cassert> |
40 | #include <cstdint> |
41 | #include <ctime> |
42 | #include <memory> |
43 | #include <stack> |
44 | #include <string> |
45 | #include <system_error> |
46 | #include <vector> |
47 | |
48 | #ifdef HAVE_SYS_STAT_H |
49 | #include <sys/stat.h> |
50 | #endif |
51 | |
52 | namespace llvm { |
53 | namespace sys { |
54 | namespace fs { |
55 | |
56 | #if defined(_WIN32) |
57 | // A Win32 HANDLE is a typedef of void* |
58 | using file_t = void *; |
59 | #else |
60 | using file_t = int; |
61 | #endif |
62 | |
63 | extern const file_t kInvalidFile; |
64 | |
65 | /// An enumeration for the file system's view of the type. |
66 | enum class file_type { |
67 | status_error, |
68 | file_not_found, |
69 | regular_file, |
70 | directory_file, |
71 | symlink_file, |
72 | block_file, |
73 | character_file, |
74 | fifo_file, |
75 | socket_file, |
76 | type_unknown |
77 | }; |
78 | |
79 | /// space_info - Self explanatory. |
80 | struct space_info { |
81 | uint64_t capacity; |
82 | uint64_t free; |
83 | uint64_t available; |
84 | }; |
85 | |
86 | enum perms { |
87 | no_perms = 0, |
88 | owner_read = 0400, |
89 | owner_write = 0200, |
90 | owner_exe = 0100, |
91 | owner_all = owner_read | owner_write | owner_exe, |
92 | group_read = 040, |
93 | group_write = 020, |
94 | group_exe = 010, |
95 | group_all = group_read | group_write | group_exe, |
96 | others_read = 04, |
97 | others_write = 02, |
98 | others_exe = 01, |
99 | others_all = others_read | others_write | others_exe, |
100 | all_read = owner_read | group_read | others_read, |
101 | all_write = owner_write | group_write | others_write, |
102 | all_exe = owner_exe | group_exe | others_exe, |
103 | all_all = owner_all | group_all | others_all, |
104 | set_uid_on_exe = 04000, |
105 | set_gid_on_exe = 02000, |
106 | sticky_bit = 01000, |
107 | all_perms = all_all | set_uid_on_exe | set_gid_on_exe | sticky_bit, |
108 | perms_not_known = 0xFFFF |
109 | }; |
110 | |
111 | // Helper functions so that you can use & and | to manipulate perms bits: |
112 | inline perms operator|(perms l, perms r) { |
113 | return static_cast<perms>(static_cast<unsigned short>(l) | |
114 | static_cast<unsigned short>(r)); |
115 | } |
116 | inline perms operator&(perms l, perms r) { |
117 | return static_cast<perms>(static_cast<unsigned short>(l) & |
118 | static_cast<unsigned short>(r)); |
119 | } |
120 | inline perms &operator|=(perms &l, perms r) { |
121 | l = l | r; |
122 | return l; |
123 | } |
124 | inline perms &operator&=(perms &l, perms r) { |
125 | l = l & r; |
126 | return l; |
127 | } |
128 | inline perms operator~(perms x) { |
129 | // Avoid UB by explicitly truncating the (unsigned) ~ result. |
130 | return static_cast<perms>( |
131 | static_cast<unsigned short>(~static_cast<unsigned short>(x))); |
132 | } |
133 | |
134 | /// Represents the result of a call to directory_iterator::status(). This is a |
135 | /// subset of the information returned by a regular sys::fs::status() call, and |
136 | /// represents the information provided by Windows FileFirstFile/FindNextFile. |
137 | class basic_file_status { |
138 | protected: |
139 | #if defined(LLVM_ON_UNIX) |
140 | time_t fs_st_atime = 0; |
141 | time_t fs_st_mtime = 0; |
142 | uint32_t fs_st_atime_nsec = 0; |
143 | uint32_t fs_st_mtime_nsec = 0; |
144 | uid_t fs_st_uid = 0; |
145 | gid_t fs_st_gid = 0; |
146 | off_t fs_st_size = 0; |
147 | #elif defined (_WIN32) |
148 | uint32_t LastAccessedTimeHigh = 0; |
149 | uint32_t LastAccessedTimeLow = 0; |
150 | uint32_t LastWriteTimeHigh = 0; |
151 | uint32_t LastWriteTimeLow = 0; |
152 | uint32_t FileSizeHigh = 0; |
153 | uint32_t FileSizeLow = 0; |
154 | #endif |
155 | file_type Type = file_type::status_error; |
156 | perms Perms = perms_not_known; |
157 | |
158 | public: |
159 | basic_file_status() = default; |
160 | |
161 | explicit basic_file_status(file_type Type) : Type(Type) {} |
162 | |
163 | #if defined(LLVM_ON_UNIX) |
164 | basic_file_status(file_type Type, perms Perms, time_t ATime, |
165 | uint32_t ATimeNSec, time_t MTime, uint32_t MTimeNSec, |
166 | uid_t UID, gid_t GID, off_t Size) |
167 | : fs_st_atime(ATime), fs_st_mtime(MTime), |
168 | fs_st_atime_nsec(ATimeNSec), fs_st_mtime_nsec(MTimeNSec), |
169 | fs_st_uid(UID), fs_st_gid(GID), |
170 | fs_st_size(Size), Type(Type), Perms(Perms) {} |
171 | #elif defined(_WIN32) |
172 | basic_file_status(file_type Type, perms Perms, uint32_t LastAccessTimeHigh, |
173 | uint32_t LastAccessTimeLow, uint32_t LastWriteTimeHigh, |
174 | uint32_t LastWriteTimeLow, uint32_t FileSizeHigh, |
175 | uint32_t FileSizeLow) |
176 | : LastAccessedTimeHigh(LastAccessTimeHigh), |
177 | LastAccessedTimeLow(LastAccessTimeLow), |
178 | LastWriteTimeHigh(LastWriteTimeHigh), |
179 | LastWriteTimeLow(LastWriteTimeLow), FileSizeHigh(FileSizeHigh), |
180 | FileSizeLow(FileSizeLow), Type(Type), Perms(Perms) {} |
181 | #endif |
182 | |
183 | // getters |
184 | file_type type() const { return Type; } |
185 | perms permissions() const { return Perms; } |
186 | |
187 | /// The file access time as reported from the underlying file system. |
188 | /// |
189 | /// Also see comments on \c getLastModificationTime() related to the precision |
190 | /// of the returned value. |
191 | TimePoint<> getLastAccessedTime() const; |
192 | |
193 | /// The file modification time as reported from the underlying file system. |
194 | /// |
195 | /// The returned value allows for nanosecond precision but the actual |
196 | /// resolution is an implementation detail of the underlying file system. |
197 | /// There is no guarantee for what kind of resolution you can expect, the |
198 | /// resolution can differ across platforms and even across mountpoints on the |
199 | /// same machine. |
200 | TimePoint<> getLastModificationTime() const; |
201 | |
202 | #if defined(LLVM_ON_UNIX) |
203 | uint32_t getUser() const { return fs_st_uid; } |
204 | uint32_t getGroup() const { return fs_st_gid; } |
205 | uint64_t getSize() const { return fs_st_size; } |
206 | #elif defined (_WIN32) |
207 | uint32_t getUser() const { |
208 | return 9999; // Not applicable to Windows, so... |
209 | } |
210 | |
211 | uint32_t getGroup() const { |
212 | return 9999; // Not applicable to Windows, so... |
213 | } |
214 | |
215 | uint64_t getSize() const { |
216 | return (uint64_t(FileSizeHigh) << 32) + FileSizeLow; |
217 | } |
218 | #endif |
219 | |
220 | // setters |
221 | void type(file_type v) { Type = v; } |
222 | void permissions(perms p) { Perms = p; } |
223 | }; |
224 | |
225 | /// Represents the result of a call to sys::fs::status(). |
226 | class file_status : public basic_file_status { |
227 | friend bool equivalent(file_status A, file_status B); |
228 | |
229 | #if defined(LLVM_ON_UNIX) |
230 | dev_t fs_st_dev = 0; |
231 | nlink_t fs_st_nlinks = 0; |
232 | ino_t fs_st_ino = 0; |
233 | #elif defined (_WIN32) |
234 | uint32_t NumLinks = 0; |
235 | uint32_t VolumeSerialNumber = 0; |
236 | uint32_t FileIndexHigh = 0; |
237 | uint32_t FileIndexLow = 0; |
238 | #endif |
239 | |
240 | public: |
241 | file_status() = default; |
242 | |
243 | explicit file_status(file_type Type) : basic_file_status(Type) {} |
244 | |
245 | #if defined(LLVM_ON_UNIX) |
246 | file_status(file_type Type, perms Perms, dev_t Dev, nlink_t Links, ino_t Ino, |
247 | time_t ATime, uint32_t ATimeNSec, |
248 | time_t MTime, uint32_t MTimeNSec, |
249 | uid_t UID, gid_t GID, off_t Size) |
250 | : basic_file_status(Type, Perms, ATime, ATimeNSec, MTime, MTimeNSec, |
251 | UID, GID, Size), |
252 | fs_st_dev(Dev), fs_st_nlinks(Links), fs_st_ino(Ino) {} |
253 | #elif defined(_WIN32) |
254 | file_status(file_type Type, perms Perms, uint32_t LinkCount, |
255 | uint32_t LastAccessTimeHigh, uint32_t LastAccessTimeLow, |
256 | uint32_t LastWriteTimeHigh, uint32_t LastWriteTimeLow, |
257 | uint32_t VolumeSerialNumber, uint32_t FileSizeHigh, |
258 | uint32_t FileSizeLow, uint32_t FileIndexHigh, |
259 | uint32_t FileIndexLow) |
260 | : basic_file_status(Type, Perms, LastAccessTimeHigh, LastAccessTimeLow, |
261 | LastWriteTimeHigh, LastWriteTimeLow, FileSizeHigh, |
262 | FileSizeLow), |
263 | NumLinks(LinkCount), VolumeSerialNumber(VolumeSerialNumber), |
264 | FileIndexHigh(FileIndexHigh), FileIndexLow(FileIndexLow) {} |
265 | #endif |
266 | |
267 | UniqueID getUniqueID() const; |
268 | uint32_t getLinkCount() const; |
269 | }; |
270 | |
271 | /// @} |
272 | /// @name Physical Operators |
273 | /// @{ |
274 | |
275 | /// Make \a path an absolute path. |
276 | /// |
277 | /// Makes \a path absolute using the \a current_directory if it is not already. |
278 | /// An empty \a path will result in the \a current_directory. |
279 | /// |
280 | /// /absolute/path => /absolute/path |
281 | /// relative/../path => <current-directory>/relative/../path |
282 | /// |
283 | /// @param path A path that is modified to be an absolute path. |
284 | void make_absolute(const Twine ¤t_directory, SmallVectorImpl<char> &path); |
285 | |
286 | /// Make \a path an absolute path. |
287 | /// |
288 | /// Makes \a path absolute using the current directory if it is not already. An |
289 | /// empty \a path will result in the current directory. |
290 | /// |
291 | /// /absolute/path => /absolute/path |
292 | /// relative/../path => <current-directory>/relative/../path |
293 | /// |
294 | /// @param path A path that is modified to be an absolute path. |
295 | /// @returns errc::success if \a path has been made absolute, otherwise a |
296 | /// platform-specific error_code. |
297 | std::error_code make_absolute(SmallVectorImpl<char> &path); |
298 | |
299 | /// Create all the non-existent directories in path. |
300 | /// |
301 | /// @param path Directories to create. |
302 | /// @returns errc::success if is_directory(path), otherwise a platform |
303 | /// specific error_code. If IgnoreExisting is false, also returns |
304 | /// error if the directory already existed. |
305 | std::error_code create_directories(const Twine &path, |
306 | bool IgnoreExisting = true, |
307 | perms Perms = owner_all | group_all); |
308 | |
309 | /// Create the directory in path. |
310 | /// |
311 | /// @param path Directory to create. |
312 | /// @returns errc::success if is_directory(path), otherwise a platform |
313 | /// specific error_code. If IgnoreExisting is false, also returns |
314 | /// error if the directory already existed. |
315 | std::error_code create_directory(const Twine &path, bool IgnoreExisting = true, |
316 | perms Perms = owner_all | group_all); |
317 | |
318 | /// Create a link from \a from to \a to. |
319 | /// |
320 | /// The link may be a soft or a hard link, depending on the platform. The caller |
321 | /// may not assume which one. Currently on windows it creates a hard link since |
322 | /// soft links require extra privileges. On unix, it creates a soft link since |
323 | /// hard links don't work on SMB file systems. |
324 | /// |
325 | /// @param to The path to hard link to. |
326 | /// @param from The path to hard link from. This is created. |
327 | /// @returns errc::success if the link was created, otherwise a platform |
328 | /// specific error_code. |
329 | std::error_code create_link(const Twine &to, const Twine &from); |
330 | |
331 | /// Create a hard link from \a from to \a to, or return an error. |
332 | /// |
333 | /// @param to The path to hard link to. |
334 | /// @param from The path to hard link from. This is created. |
335 | /// @returns errc::success if the link was created, otherwise a platform |
336 | /// specific error_code. |
337 | std::error_code create_hard_link(const Twine &to, const Twine &from); |
338 | |
339 | /// Collapse all . and .. patterns, resolve all symlinks, and optionally |
340 | /// expand ~ expressions to the user's home directory. |
341 | /// |
342 | /// @param path The path to resolve. |
343 | /// @param output The location to store the resolved path. |
344 | /// @param expand_tilde If true, resolves ~ expressions to the user's home |
345 | /// directory. |
346 | std::error_code real_path(const Twine &path, SmallVectorImpl<char> &output, |
347 | bool expand_tilde = false); |
348 | |
349 | /// Expands ~ expressions to the user's home directory. On Unix ~user |
350 | /// directories are resolved as well. |
351 | /// |
352 | /// @param path The path to resolve. |
353 | void expand_tilde(const Twine &path, SmallVectorImpl<char> &output); |
354 | |
355 | /// Get the current path. |
356 | /// |
357 | /// @param result Holds the current path on return. |
358 | /// @returns errc::success if the current path has been stored in result, |
359 | /// otherwise a platform-specific error_code. |
360 | std::error_code current_path(SmallVectorImpl<char> &result); |
361 | |
362 | /// Set the current path. |
363 | /// |
364 | /// @param path The path to set. |
365 | /// @returns errc::success if the current path was successfully set, |
366 | /// otherwise a platform-specific error_code. |
367 | std::error_code set_current_path(const Twine &path); |
368 | |
369 | /// Remove path. Equivalent to POSIX remove(). |
370 | /// |
371 | /// @param path Input path. |
372 | /// @returns errc::success if path has been removed or didn't exist, otherwise a |
373 | /// platform-specific error code. If IgnoreNonExisting is false, also |
374 | /// returns error if the file didn't exist. |
375 | std::error_code remove(const Twine &path, bool IgnoreNonExisting = true); |
376 | |
377 | /// Recursively delete a directory. |
378 | /// |
379 | /// @param path Input path. |
380 | /// @returns errc::success if path has been removed or didn't exist, otherwise a |
381 | /// platform-specific error code. |
382 | std::error_code remove_directories(const Twine &path, bool IgnoreErrors = true); |
383 | |
384 | /// Rename \a from to \a to. |
385 | /// |
386 | /// Files are renamed as if by POSIX rename(), except that on Windows there may |
387 | /// be a short interval of time during which the destination file does not |
388 | /// exist. |
389 | /// |
390 | /// @param from The path to rename from. |
391 | /// @param to The path to rename to. This is created. |
392 | std::error_code rename(const Twine &from, const Twine &to); |
393 | |
394 | /// Copy the contents of \a From to \a To. |
395 | /// |
396 | /// @param From The path to copy from. |
397 | /// @param To The path to copy to. This is created. |
398 | std::error_code copy_file(const Twine &From, const Twine &To); |
399 | |
400 | /// Copy the contents of \a From to \a To. |
401 | /// |
402 | /// @param From The path to copy from. |
403 | /// @param ToFD The open file descriptor of the destination file. |
404 | std::error_code copy_file(const Twine &From, int ToFD); |
405 | |
406 | /// Resize path to size. File is resized as if by POSIX truncate(). |
407 | /// |
408 | /// @param FD Input file descriptor. |
409 | /// @param Size Size to resize to. |
410 | /// @returns errc::success if \a path has been resized to \a size, otherwise a |
411 | /// platform-specific error_code. |
412 | std::error_code resize_file(int FD, uint64_t Size); |
413 | |
414 | /// Resize \p FD to \p Size before mapping \a mapped_file_region::readwrite. On |
415 | /// non-Windows, this calls \a resize_file(). On Windows, this is a no-op, |
416 | /// since the subsequent mapping (via \c CreateFileMapping) automatically |
417 | /// extends the file. |
418 | inline std::error_code resize_file_before_mapping_readwrite(int FD, |
419 | uint64_t Size) { |
420 | #ifdef _WIN32 |
421 | (void)FD; |
422 | (void)Size; |
423 | return std::error_code(); |
424 | #else |
425 | return resize_file(FD, Size); |
426 | #endif |
427 | } |
428 | |
429 | /// Compute an MD5 hash of a file's contents. |
430 | /// |
431 | /// @param FD Input file descriptor. |
432 | /// @returns An MD5Result with the hash computed, if successful, otherwise a |
433 | /// std::error_code. |
434 | ErrorOr<MD5::MD5Result> md5_contents(int FD); |
435 | |
436 | /// Version of compute_md5 that doesn't require an open file descriptor. |
437 | ErrorOr<MD5::MD5Result> md5_contents(const Twine &Path); |
438 | |
439 | /// @} |
440 | /// @name Physical Observers |
441 | /// @{ |
442 | |
443 | /// Does file exist? |
444 | /// |
445 | /// @param status A basic_file_status previously returned from stat. |
446 | /// @returns True if the file represented by status exists, false if it does |
447 | /// not. |
448 | bool exists(const basic_file_status &status); |
449 | |
450 | enum class AccessMode { Exist, Write, Execute }; |
451 | |
452 | /// Can the file be accessed? |
453 | /// |
454 | /// @param Path Input path. |
455 | /// @returns errc::success if the path can be accessed, otherwise a |
456 | /// platform-specific error_code. |
457 | std::error_code access(const Twine &Path, AccessMode Mode); |
458 | |
459 | /// Does file exist? |
460 | /// |
461 | /// @param Path Input path. |
462 | /// @returns True if it exists, false otherwise. |
463 | inline bool exists(const Twine &Path) { |
464 | return !access(Path, Mode: AccessMode::Exist); |
465 | } |
466 | |
467 | /// Can we execute this file? |
468 | /// |
469 | /// @param Path Input path. |
470 | /// @returns True if we can execute it, false otherwise. |
471 | bool can_execute(const Twine &Path); |
472 | |
473 | /// Can we write this file? |
474 | /// |
475 | /// @param Path Input path. |
476 | /// @returns True if we can write to it, false otherwise. |
477 | inline bool can_write(const Twine &Path) { |
478 | return !access(Path, Mode: AccessMode::Write); |
479 | } |
480 | |
481 | /// Do file_status's represent the same thing? |
482 | /// |
483 | /// @param A Input file_status. |
484 | /// @param B Input file_status. |
485 | /// |
486 | /// assert(status_known(A) || status_known(B)); |
487 | /// |
488 | /// @returns True if A and B both represent the same file system entity, false |
489 | /// otherwise. |
490 | bool equivalent(file_status A, file_status B); |
491 | |
492 | /// Do paths represent the same thing? |
493 | /// |
494 | /// assert(status_known(A) || status_known(B)); |
495 | /// |
496 | /// @param A Input path A. |
497 | /// @param B Input path B. |
498 | /// @param result Set to true if stat(A) and stat(B) have the same device and |
499 | /// inode (or equivalent). |
500 | /// @returns errc::success if result has been successfully set, otherwise a |
501 | /// platform-specific error_code. |
502 | std::error_code equivalent(const Twine &A, const Twine &B, bool &result); |
503 | |
504 | /// Simpler version of equivalent for clients that don't need to |
505 | /// differentiate between an error and false. |
506 | inline bool equivalent(const Twine &A, const Twine &B) { |
507 | bool result; |
508 | return !equivalent(A, B, result) && result; |
509 | } |
510 | |
511 | /// Is the file mounted on a local filesystem? |
512 | /// |
513 | /// @param path Input path. |
514 | /// @param result Set to true if \a path is on fixed media such as a hard disk, |
515 | /// false if it is not. |
516 | /// @returns errc::success if result has been successfully set, otherwise a |
517 | /// platform specific error_code. |
518 | std::error_code is_local(const Twine &path, bool &result); |
519 | |
520 | /// Version of is_local accepting an open file descriptor. |
521 | std::error_code is_local(int FD, bool &result); |
522 | |
523 | /// Simpler version of is_local for clients that don't need to |
524 | /// differentiate between an error and false. |
525 | inline bool is_local(const Twine &Path) { |
526 | bool Result; |
527 | return !is_local(path: Path, result&: Result) && Result; |
528 | } |
529 | |
530 | /// Simpler version of is_local accepting an open file descriptor for |
531 | /// clients that don't need to differentiate between an error and false. |
532 | inline bool is_local(int FD) { |
533 | bool Result; |
534 | return !is_local(FD, result&: Result) && Result; |
535 | } |
536 | |
537 | /// Does status represent a directory? |
538 | /// |
539 | /// @param Path The path to get the type of. |
540 | /// @param Follow For symbolic links, indicates whether to return the file type |
541 | /// of the link itself, or of the target. |
542 | /// @returns A value from the file_type enumeration indicating the type of file. |
543 | file_type get_file_type(const Twine &Path, bool Follow = true); |
544 | |
545 | /// Does status represent a directory? |
546 | /// |
547 | /// @param status A basic_file_status previously returned from status. |
548 | /// @returns status.type() == file_type::directory_file. |
549 | bool is_directory(const basic_file_status &status); |
550 | |
551 | /// Is path a directory? |
552 | /// |
553 | /// @param path Input path. |
554 | /// @param result Set to true if \a path is a directory (after following |
555 | /// symlinks, false if it is not. Undefined otherwise. |
556 | /// @returns errc::success if result has been successfully set, otherwise a |
557 | /// platform-specific error_code. |
558 | std::error_code is_directory(const Twine &path, bool &result); |
559 | |
560 | /// Simpler version of is_directory for clients that don't need to |
561 | /// differentiate between an error and false. |
562 | inline bool is_directory(const Twine &Path) { |
563 | bool Result; |
564 | return !is_directory(path: Path, result&: Result) && Result; |
565 | } |
566 | |
567 | /// Does status represent a regular file? |
568 | /// |
569 | /// @param status A basic_file_status previously returned from status. |
570 | /// @returns status_known(status) && status.type() == file_type::regular_file. |
571 | bool is_regular_file(const basic_file_status &status); |
572 | |
573 | /// Is path a regular file? |
574 | /// |
575 | /// @param path Input path. |
576 | /// @param result Set to true if \a path is a regular file (after following |
577 | /// symlinks), false if it is not. Undefined otherwise. |
578 | /// @returns errc::success if result has been successfully set, otherwise a |
579 | /// platform-specific error_code. |
580 | std::error_code is_regular_file(const Twine &path, bool &result); |
581 | |
582 | /// Simpler version of is_regular_file for clients that don't need to |
583 | /// differentiate between an error and false. |
584 | inline bool is_regular_file(const Twine &Path) { |
585 | bool Result; |
586 | if (is_regular_file(path: Path, result&: Result)) |
587 | return false; |
588 | return Result; |
589 | } |
590 | |
591 | /// Does status represent a symlink file? |
592 | /// |
593 | /// @param status A basic_file_status previously returned from status. |
594 | /// @returns status_known(status) && status.type() == file_type::symlink_file. |
595 | bool is_symlink_file(const basic_file_status &status); |
596 | |
597 | /// Is path a symlink file? |
598 | /// |
599 | /// @param path Input path. |
600 | /// @param result Set to true if \a path is a symlink file, false if it is not. |
601 | /// Undefined otherwise. |
602 | /// @returns errc::success if result has been successfully set, otherwise a |
603 | /// platform-specific error_code. |
604 | std::error_code is_symlink_file(const Twine &path, bool &result); |
605 | |
606 | /// Simpler version of is_symlink_file for clients that don't need to |
607 | /// differentiate between an error and false. |
608 | inline bool is_symlink_file(const Twine &Path) { |
609 | bool Result; |
610 | if (is_symlink_file(path: Path, result&: Result)) |
611 | return false; |
612 | return Result; |
613 | } |
614 | |
615 | /// Does this status represent something that exists but is not a |
616 | /// directory or regular file? |
617 | /// |
618 | /// @param status A basic_file_status previously returned from status. |
619 | /// @returns exists(s) && !is_regular_file(s) && !is_directory(s) |
620 | bool is_other(const basic_file_status &status); |
621 | |
622 | /// Is path something that exists but is not a directory, |
623 | /// regular file, or symlink? |
624 | /// |
625 | /// @param path Input path. |
626 | /// @param result Set to true if \a path exists, but is not a directory, regular |
627 | /// file, or a symlink, false if it does not. Undefined otherwise. |
628 | /// @returns errc::success if result has been successfully set, otherwise a |
629 | /// platform-specific error_code. |
630 | std::error_code is_other(const Twine &path, bool &result); |
631 | |
632 | /// Get file status as if by POSIX stat(). |
633 | /// |
634 | /// @param path Input path. |
635 | /// @param result Set to the file status. |
636 | /// @param follow When true, follows symlinks. Otherwise, the symlink itself is |
637 | /// statted. |
638 | /// @returns errc::success if result has been successfully set, otherwise a |
639 | /// platform-specific error_code. |
640 | std::error_code status(const Twine &path, file_status &result, |
641 | bool follow = true); |
642 | |
643 | /// A version for when a file descriptor is already available. |
644 | std::error_code status(int FD, file_status &Result); |
645 | |
646 | #ifdef _WIN32 |
647 | /// A version for when a file descriptor is already available. |
648 | std::error_code status(file_t FD, file_status &Result); |
649 | #endif |
650 | |
651 | /// Get file creation mode mask of the process. |
652 | /// |
653 | /// @returns Mask reported by umask(2) |
654 | /// @note There is no umask on Windows. This function returns 0 always |
655 | /// on Windows. This function does not return an error_code because |
656 | /// umask(2) never fails. It is not thread safe. |
657 | unsigned getUmask(); |
658 | |
659 | /// Set file permissions. |
660 | /// |
661 | /// @param Path File to set permissions on. |
662 | /// @param Permissions New file permissions. |
663 | /// @returns errc::success if the permissions were successfully set, otherwise |
664 | /// a platform-specific error_code. |
665 | /// @note On Windows, all permissions except *_write are ignored. Using any of |
666 | /// owner_write, group_write, or all_write will make the file writable. |
667 | /// Otherwise, the file will be marked as read-only. |
668 | std::error_code setPermissions(const Twine &Path, perms Permissions); |
669 | |
670 | /// Vesion of setPermissions accepting a file descriptor. |
671 | /// TODO Delete the path based overload once we implement the FD based overload |
672 | /// on Windows. |
673 | std::error_code setPermissions(int FD, perms Permissions); |
674 | |
675 | /// Get file permissions. |
676 | /// |
677 | /// @param Path File to get permissions from. |
678 | /// @returns the permissions if they were successfully retrieved, otherwise a |
679 | /// platform-specific error_code. |
680 | /// @note On Windows, if the file does not have the FILE_ATTRIBUTE_READONLY |
681 | /// attribute, all_all will be returned. Otherwise, all_read | all_exe |
682 | /// will be returned. |
683 | ErrorOr<perms> getPermissions(const Twine &Path); |
684 | |
685 | /// Get file size. |
686 | /// |
687 | /// @param Path Input path. |
688 | /// @param Result Set to the size of the file in \a Path. |
689 | /// @returns errc::success if result has been successfully set, otherwise a |
690 | /// platform-specific error_code. |
691 | inline std::error_code file_size(const Twine &Path, uint64_t &Result) { |
692 | file_status Status; |
693 | std::error_code EC = status(path: Path, result&: Status); |
694 | if (EC) |
695 | return EC; |
696 | Result = Status.getSize(); |
697 | return std::error_code(); |
698 | } |
699 | |
700 | /// Set the file modification and access time. |
701 | /// |
702 | /// @returns errc::success if the file times were successfully set, otherwise a |
703 | /// platform-specific error_code or errc::function_not_supported on |
704 | /// platforms where the functionality isn't available. |
705 | std::error_code setLastAccessAndModificationTime(int FD, TimePoint<> AccessTime, |
706 | TimePoint<> ModificationTime); |
707 | |
708 | /// Simpler version that sets both file modification and access time to the same |
709 | /// time. |
710 | inline std::error_code setLastAccessAndModificationTime(int FD, |
711 | TimePoint<> Time) { |
712 | return setLastAccessAndModificationTime(FD, AccessTime: Time, ModificationTime: Time); |
713 | } |
714 | |
715 | /// Is status available? |
716 | /// |
717 | /// @param s Input file status. |
718 | /// @returns True if status() != status_error. |
719 | bool status_known(const basic_file_status &s); |
720 | |
721 | /// Is status available? |
722 | /// |
723 | /// @param path Input path. |
724 | /// @param result Set to true if status() != status_error. |
725 | /// @returns errc::success if result has been successfully set, otherwise a |
726 | /// platform-specific error_code. |
727 | std::error_code status_known(const Twine &path, bool &result); |
728 | |
729 | enum CreationDisposition : unsigned { |
730 | /// CD_CreateAlways - When opening a file: |
731 | /// * If it already exists, truncate it. |
732 | /// * If it does not already exist, create a new file. |
733 | CD_CreateAlways = 0, |
734 | |
735 | /// CD_CreateNew - When opening a file: |
736 | /// * If it already exists, fail. |
737 | /// * If it does not already exist, create a new file. |
738 | CD_CreateNew = 1, |
739 | |
740 | /// CD_OpenExisting - When opening a file: |
741 | /// * If it already exists, open the file with the offset set to 0. |
742 | /// * If it does not already exist, fail. |
743 | CD_OpenExisting = 2, |
744 | |
745 | /// CD_OpenAlways - When opening a file: |
746 | /// * If it already exists, open the file with the offset set to 0. |
747 | /// * If it does not already exist, create a new file. |
748 | CD_OpenAlways = 3, |
749 | }; |
750 | |
751 | enum FileAccess : unsigned { |
752 | FA_Read = 1, |
753 | FA_Write = 2, |
754 | }; |
755 | |
756 | enum OpenFlags : unsigned { |
757 | OF_None = 0, |
758 | |
759 | /// The file should be opened in text mode on platforms like z/OS that make |
760 | /// this distinction. |
761 | OF_Text = 1, |
762 | |
763 | /// The file should use a carriage linefeed '\r\n'. This flag should only be |
764 | /// used with OF_Text. Only makes a difference on Windows. |
765 | OF_CRLF = 2, |
766 | |
767 | /// The file should be opened in text mode and use a carriage linefeed '\r\n'. |
768 | /// This flag has the same functionality as OF_Text on z/OS but adds a |
769 | /// carriage linefeed on Windows. |
770 | OF_TextWithCRLF = OF_Text | OF_CRLF, |
771 | |
772 | /// The file should be opened in append mode. |
773 | OF_Append = 4, |
774 | |
775 | /// The returned handle can be used for deleting the file. Only makes a |
776 | /// difference on windows. |
777 | OF_Delete = 8, |
778 | |
779 | /// When a child process is launched, this file should remain open in the |
780 | /// child process. |
781 | OF_ChildInherit = 16, |
782 | |
783 | /// Force files Atime to be updated on access. Only makes a difference on |
784 | /// Windows. |
785 | OF_UpdateAtime = 32, |
786 | }; |
787 | |
788 | /// Create a potentially unique file name but does not create it. |
789 | /// |
790 | /// Generates a unique path suitable for a temporary file but does not |
791 | /// open or create the file. The name is based on \a Model with '%' |
792 | /// replaced by a random char in [0-9a-f]. If \a MakeAbsolute is true |
793 | /// then the system's temp directory is prepended first. If \a MakeAbsolute |
794 | /// is false the current directory will be used instead. |
795 | /// |
796 | /// This function does not check if the file exists. If you want to be sure |
797 | /// that the file does not yet exist, you should use use enough '%' characters |
798 | /// in your model to ensure this. Each '%' gives 4-bits of entropy so you can |
799 | /// use 32 of them to get 128 bits of entropy. |
800 | /// |
801 | /// Example: clang-%%-%%-%%-%%-%%.s => clang-a0-b1-c2-d3-e4.s |
802 | /// |
803 | /// @param Model Name to base unique path off of. |
804 | /// @param ResultPath Set to the file's path. |
805 | /// @param MakeAbsolute Whether to use the system temp directory. |
806 | void createUniquePath(const Twine &Model, SmallVectorImpl<char> &ResultPath, |
807 | bool MakeAbsolute); |
808 | |
809 | /// Create a uniquely named file. |
810 | /// |
811 | /// Generates a unique path suitable for a temporary file and then opens it as a |
812 | /// file. The name is based on \a Model with '%' replaced by a random char in |
813 | /// [0-9a-f]. If \a Model is not an absolute path, the temporary file will be |
814 | /// created in the current directory. |
815 | /// |
816 | /// Example: clang-%%-%%-%%-%%-%%.s => clang-a0-b1-c2-d3-e4.s |
817 | /// |
818 | /// This is an atomic operation. Either the file is created and opened, or the |
819 | /// file system is left untouched. |
820 | /// |
821 | /// The intended use is for files that are to be kept, possibly after |
822 | /// renaming them. For example, when running 'clang -c foo.o', the file can |
823 | /// be first created as foo-abc123.o and then renamed. |
824 | /// |
825 | /// @param Model Name to base unique path off of. |
826 | /// @param ResultFD Set to the opened file's file descriptor. |
827 | /// @param ResultPath Set to the opened file's absolute path. |
828 | /// @param Flags Set to the opened file's flags. |
829 | /// @param Mode Set to the opened file's permissions. |
830 | /// @returns errc::success if Result{FD,Path} have been successfully set, |
831 | /// otherwise a platform-specific error_code. |
832 | std::error_code createUniqueFile(const Twine &Model, int &ResultFD, |
833 | SmallVectorImpl<char> &ResultPath, |
834 | OpenFlags Flags = OF_None, |
835 | unsigned Mode = all_read | all_write); |
836 | |
837 | /// Simpler version for clients that don't want an open file. An empty |
838 | /// file will still be created. |
839 | std::error_code createUniqueFile(const Twine &Model, |
840 | SmallVectorImpl<char> &ResultPath, |
841 | unsigned Mode = all_read | all_write); |
842 | |
843 | /// Represents a temporary file. |
844 | /// |
845 | /// The temporary file must be eventually discarded or given a final name and |
846 | /// kept. |
847 | /// |
848 | /// The destructor doesn't implicitly discard because there is no way to |
849 | /// properly handle errors in a destructor. |
850 | class TempFile { |
851 | bool Done = false; |
852 | TempFile(StringRef Name, int FD); |
853 | |
854 | public: |
855 | /// This creates a temporary file with createUniqueFile and schedules it for |
856 | /// deletion with sys::RemoveFileOnSignal. |
857 | static Expected<TempFile> create(const Twine &Model, |
858 | unsigned Mode = all_read | all_write, |
859 | OpenFlags = OF_None); |
860 | TempFile(TempFile &&Other); |
861 | TempFile &operator=(TempFile &&Other); |
862 | |
863 | // Name of the temporary file. |
864 | std::string TmpName; |
865 | |
866 | // The open file descriptor. |
867 | int FD = -1; |
868 | |
869 | #ifdef _WIN32 |
870 | // Whether we need to manually remove the file on close. |
871 | bool RemoveOnClose = false; |
872 | #endif |
873 | |
874 | // Keep this with the given name. |
875 | Error keep(const Twine &Name); |
876 | |
877 | // Keep this with the temporary name. |
878 | Error keep(); |
879 | |
880 | // Delete the file. |
881 | Error discard(); |
882 | |
883 | // This checks that keep or delete was called. |
884 | ~TempFile(); |
885 | }; |
886 | |
887 | /// Create a file in the system temporary directory. |
888 | /// |
889 | /// The filename is of the form prefix-random_chars.suffix. Since the directory |
890 | /// is not know to the caller, Prefix and Suffix cannot have path separators. |
891 | /// The files are created with mode 0600. |
892 | /// |
893 | /// This should be used for things like a temporary .s that is removed after |
894 | /// running the assembler. |
895 | std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix, |
896 | int &ResultFD, |
897 | SmallVectorImpl<char> &ResultPath, |
898 | OpenFlags Flags = OF_None); |
899 | |
900 | /// Simpler version for clients that don't want an open file. An empty |
901 | /// file will still be created. |
902 | std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix, |
903 | SmallVectorImpl<char> &ResultPath, |
904 | OpenFlags Flags = OF_None); |
905 | |
906 | std::error_code createUniqueDirectory(const Twine &Prefix, |
907 | SmallVectorImpl<char> &ResultPath); |
908 | |
909 | /// Get a unique name, not currently exisiting in the filesystem. Subject |
910 | /// to race conditions, prefer to use createUniqueFile instead. |
911 | /// |
912 | /// Similar to createUniqueFile, but instead of creating a file only |
913 | /// checks if it exists. This function is subject to race conditions, if you |
914 | /// want to use the returned name to actually create a file, use |
915 | /// createUniqueFile instead. |
916 | std::error_code getPotentiallyUniqueFileName(const Twine &Model, |
917 | SmallVectorImpl<char> &ResultPath); |
918 | |
919 | /// Get a unique temporary file name, not currently exisiting in the |
920 | /// filesystem. Subject to race conditions, prefer to use createTemporaryFile |
921 | /// instead. |
922 | /// |
923 | /// Similar to createTemporaryFile, but instead of creating a file only |
924 | /// checks if it exists. This function is subject to race conditions, if you |
925 | /// want to use the returned name to actually create a file, use |
926 | /// createTemporaryFile instead. |
927 | std::error_code |
928 | getPotentiallyUniqueTempFileName(const Twine &Prefix, StringRef Suffix, |
929 | SmallVectorImpl<char> &ResultPath); |
930 | |
931 | inline OpenFlags operator|(OpenFlags A, OpenFlags B) { |
932 | return OpenFlags(unsigned(A) | unsigned(B)); |
933 | } |
934 | |
935 | inline OpenFlags &operator|=(OpenFlags &A, OpenFlags B) { |
936 | A = A | B; |
937 | return A; |
938 | } |
939 | |
940 | inline FileAccess operator|(FileAccess A, FileAccess B) { |
941 | return FileAccess(unsigned(A) | unsigned(B)); |
942 | } |
943 | |
944 | inline FileAccess &operator|=(FileAccess &A, FileAccess B) { |
945 | A = A | B; |
946 | return A; |
947 | } |
948 | |
949 | /// @brief Opens a file with the specified creation disposition, access mode, |
950 | /// and flags and returns a file descriptor. |
951 | /// |
952 | /// The caller is responsible for closing the file descriptor once they are |
953 | /// finished with it. |
954 | /// |
955 | /// @param Name The path of the file to open, relative or absolute. |
956 | /// @param ResultFD If the file could be opened successfully, its descriptor |
957 | /// is stored in this location. Otherwise, this is set to -1. |
958 | /// @param Disp Value specifying the existing-file behavior. |
959 | /// @param Access Value specifying whether to open the file in read, write, or |
960 | /// read-write mode. |
961 | /// @param Flags Additional flags. |
962 | /// @param Mode The access permissions of the file, represented in octal. |
963 | /// @returns errc::success if \a Name has been opened, otherwise a |
964 | /// platform-specific error_code. |
965 | std::error_code openFile(const Twine &Name, int &ResultFD, |
966 | CreationDisposition Disp, FileAccess Access, |
967 | OpenFlags Flags, unsigned Mode = 0666); |
968 | |
969 | /// @brief Opens a file with the specified creation disposition, access mode, |
970 | /// and flags and returns a platform-specific file object. |
971 | /// |
972 | /// The caller is responsible for closing the file object once they are |
973 | /// finished with it. |
974 | /// |
975 | /// @param Name The path of the file to open, relative or absolute. |
976 | /// @param Disp Value specifying the existing-file behavior. |
977 | /// @param Access Value specifying whether to open the file in read, write, or |
978 | /// read-write mode. |
979 | /// @param Flags Additional flags. |
980 | /// @param Mode The access permissions of the file, represented in octal. |
981 | /// @returns errc::success if \a Name has been opened, otherwise a |
982 | /// platform-specific error_code. |
983 | Expected<file_t> openNativeFile(const Twine &Name, CreationDisposition Disp, |
984 | FileAccess Access, OpenFlags Flags, |
985 | unsigned Mode = 0666); |
986 | |
987 | /// Converts from a Posix file descriptor number to a native file handle. |
988 | /// On Windows, this retreives the underlying handle. On non-Windows, this is a |
989 | /// no-op. |
990 | file_t convertFDToNativeFile(int FD); |
991 | |
992 | #ifndef _WIN32 |
993 | inline file_t convertFDToNativeFile(int FD) { return FD; } |
994 | #endif |
995 | |
996 | /// Return an open handle to standard in. On Unix, this is typically FD 0. |
997 | /// Returns kInvalidFile when the stream is closed. |
998 | file_t getStdinHandle(); |
999 | |
1000 | /// Return an open handle to standard out. On Unix, this is typically FD 1. |
1001 | /// Returns kInvalidFile when the stream is closed. |
1002 | file_t getStdoutHandle(); |
1003 | |
1004 | /// Return an open handle to standard error. On Unix, this is typically FD 2. |
1005 | /// Returns kInvalidFile when the stream is closed. |
1006 | file_t getStderrHandle(); |
1007 | |
1008 | /// Reads \p Buf.size() bytes from \p FileHandle into \p Buf. Returns the number |
1009 | /// of bytes actually read. On Unix, this is equivalent to `return ::read(FD, |
1010 | /// Buf.data(), Buf.size())`, with error reporting. Returns 0 when reaching EOF. |
1011 | /// |
1012 | /// @param FileHandle File to read from. |
1013 | /// @param Buf Buffer to read into. |
1014 | /// @returns The number of bytes read, or error. |
1015 | Expected<size_t> readNativeFile(file_t FileHandle, MutableArrayRef<char> Buf); |
1016 | |
1017 | /// Default chunk size for \a readNativeFileToEOF(). |
1018 | enum : size_t { DefaultReadChunkSize = 4 * 4096 }; |
1019 | |
1020 | /// Reads from \p FileHandle until EOF, appending to \p Buffer in chunks of |
1021 | /// size \p ChunkSize. |
1022 | /// |
1023 | /// This calls \a readNativeFile() in a loop. On Error, previous chunks that |
1024 | /// were read successfully are left in \p Buffer and returned. |
1025 | /// |
1026 | /// Note: For reading the final chunk at EOF, \p Buffer's capacity needs extra |
1027 | /// storage of \p ChunkSize. |
1028 | /// |
1029 | /// \param FileHandle File to read from. |
1030 | /// \param Buffer Where to put the file content. |
1031 | /// \param ChunkSize Size of chunks. |
1032 | /// \returns The error if EOF was not found. |
1033 | Error readNativeFileToEOF(file_t FileHandle, SmallVectorImpl<char> &Buffer, |
1034 | ssize_t ChunkSize = DefaultReadChunkSize); |
1035 | |
1036 | /// Reads \p Buf.size() bytes from \p FileHandle at offset \p Offset into \p |
1037 | /// Buf. If 'pread' is available, this will use that, otherwise it will use |
1038 | /// 'lseek'. Returns the number of bytes actually read. Returns 0 when reaching |
1039 | /// EOF. |
1040 | /// |
1041 | /// @param FileHandle File to read from. |
1042 | /// @param Buf Buffer to read into. |
1043 | /// @param Offset Offset into the file at which the read should occur. |
1044 | /// @returns The number of bytes read, or error. |
1045 | Expected<size_t> readNativeFileSlice(file_t FileHandle, |
1046 | MutableArrayRef<char> Buf, |
1047 | uint64_t Offset); |
1048 | |
1049 | /// @brief Opens the file with the given name in a write-only or read-write |
1050 | /// mode, returning its open file descriptor. If the file does not exist, it |
1051 | /// is created. |
1052 | /// |
1053 | /// The caller is responsible for closing the file descriptor once they are |
1054 | /// finished with it. |
1055 | /// |
1056 | /// @param Name The path of the file to open, relative or absolute. |
1057 | /// @param ResultFD If the file could be opened successfully, its descriptor |
1058 | /// is stored in this location. Otherwise, this is set to -1. |
1059 | /// @param Flags Additional flags used to determine whether the file should be |
1060 | /// opened in, for example, read-write or in write-only mode. |
1061 | /// @param Mode The access permissions of the file, represented in octal. |
1062 | /// @returns errc::success if \a Name has been opened, otherwise a |
1063 | /// platform-specific error_code. |
1064 | inline std::error_code |
1065 | openFileForWrite(const Twine &Name, int &ResultFD, |
1066 | CreationDisposition Disp = CD_CreateAlways, |
1067 | OpenFlags Flags = OF_None, unsigned Mode = 0666) { |
1068 | return openFile(Name, ResultFD, Disp, Access: FA_Write, Flags, Mode); |
1069 | } |
1070 | |
1071 | /// @brief Opens the file with the given name in a write-only or read-write |
1072 | /// mode, returning its open file descriptor. If the file does not exist, it |
1073 | /// is created. |
1074 | /// |
1075 | /// The caller is responsible for closing the freeing the file once they are |
1076 | /// finished with it. |
1077 | /// |
1078 | /// @param Name The path of the file to open, relative or absolute. |
1079 | /// @param Flags Additional flags used to determine whether the file should be |
1080 | /// opened in, for example, read-write or in write-only mode. |
1081 | /// @param Mode The access permissions of the file, represented in octal. |
1082 | /// @returns a platform-specific file descriptor if \a Name has been opened, |
1083 | /// otherwise an error object. |
1084 | inline Expected<file_t> openNativeFileForWrite(const Twine &Name, |
1085 | CreationDisposition Disp, |
1086 | OpenFlags Flags, |
1087 | unsigned Mode = 0666) { |
1088 | return openNativeFile(Name, Disp, Access: FA_Write, Flags, Mode); |
1089 | } |
1090 | |
1091 | /// @brief Opens the file with the given name in a write-only or read-write |
1092 | /// mode, returning its open file descriptor. If the file does not exist, it |
1093 | /// is created. |
1094 | /// |
1095 | /// The caller is responsible for closing the file descriptor once they are |
1096 | /// finished with it. |
1097 | /// |
1098 | /// @param Name The path of the file to open, relative or absolute. |
1099 | /// @param ResultFD If the file could be opened successfully, its descriptor |
1100 | /// is stored in this location. Otherwise, this is set to -1. |
1101 | /// @param Flags Additional flags used to determine whether the file should be |
1102 | /// opened in, for example, read-write or in write-only mode. |
1103 | /// @param Mode The access permissions of the file, represented in octal. |
1104 | /// @returns errc::success if \a Name has been opened, otherwise a |
1105 | /// platform-specific error_code. |
1106 | inline std::error_code openFileForReadWrite(const Twine &Name, int &ResultFD, |
1107 | CreationDisposition Disp, |
1108 | OpenFlags Flags, |
1109 | unsigned Mode = 0666) { |
1110 | return openFile(Name, ResultFD, Disp, Access: FA_Write | FA_Read, Flags, Mode); |
1111 | } |
1112 | |
1113 | /// @brief Opens the file with the given name in a write-only or read-write |
1114 | /// mode, returning its open file descriptor. If the file does not exist, it |
1115 | /// is created. |
1116 | /// |
1117 | /// The caller is responsible for closing the freeing the file once they are |
1118 | /// finished with it. |
1119 | /// |
1120 | /// @param Name The path of the file to open, relative or absolute. |
1121 | /// @param Flags Additional flags used to determine whether the file should be |
1122 | /// opened in, for example, read-write or in write-only mode. |
1123 | /// @param Mode The access permissions of the file, represented in octal. |
1124 | /// @returns a platform-specific file descriptor if \a Name has been opened, |
1125 | /// otherwise an error object. |
1126 | inline Expected<file_t> openNativeFileForReadWrite(const Twine &Name, |
1127 | CreationDisposition Disp, |
1128 | OpenFlags Flags, |
1129 | unsigned Mode = 0666) { |
1130 | return openNativeFile(Name, Disp, Access: FA_Write | FA_Read, Flags, Mode); |
1131 | } |
1132 | |
1133 | /// @brief Opens the file with the given name in a read-only mode, returning |
1134 | /// its open file descriptor. |
1135 | /// |
1136 | /// The caller is responsible for closing the file descriptor once they are |
1137 | /// finished with it. |
1138 | /// |
1139 | /// @param Name The path of the file to open, relative or absolute. |
1140 | /// @param ResultFD If the file could be opened successfully, its descriptor |
1141 | /// is stored in this location. Otherwise, this is set to -1. |
1142 | /// @param RealPath If nonnull, extra work is done to determine the real path |
1143 | /// of the opened file, and that path is stored in this |
1144 | /// location. |
1145 | /// @returns errc::success if \a Name has been opened, otherwise a |
1146 | /// platform-specific error_code. |
1147 | std::error_code openFileForRead(const Twine &Name, int &ResultFD, |
1148 | OpenFlags Flags = OF_None, |
1149 | SmallVectorImpl<char> *RealPath = nullptr); |
1150 | |
1151 | /// @brief Opens the file with the given name in a read-only mode, returning |
1152 | /// its open file descriptor. |
1153 | /// |
1154 | /// The caller is responsible for closing the freeing the file once they are |
1155 | /// finished with it. |
1156 | /// |
1157 | /// @param Name The path of the file to open, relative or absolute. |
1158 | /// @param RealPath If nonnull, extra work is done to determine the real path |
1159 | /// of the opened file, and that path is stored in this |
1160 | /// location. |
1161 | /// @returns a platform-specific file descriptor if \a Name has been opened, |
1162 | /// otherwise an error object. |
1163 | Expected<file_t> |
1164 | openNativeFileForRead(const Twine &Name, OpenFlags Flags = OF_None, |
1165 | SmallVectorImpl<char> *RealPath = nullptr); |
1166 | |
1167 | /// Try to locks the file during the specified time. |
1168 | /// |
1169 | /// This function implements advisory locking on entire file. If it returns |
1170 | /// <em>errc::success</em>, the file is locked by the calling process. Until the |
1171 | /// process unlocks the file by calling \a unlockFile, all attempts to lock the |
1172 | /// same file will fail/block. The process that locked the file may assume that |
1173 | /// none of other processes read or write this file, provided that all processes |
1174 | /// lock the file prior to accessing its content. |
1175 | /// |
1176 | /// @param FD The descriptor representing the file to lock. |
1177 | /// @param Timeout Time in milliseconds that the process should wait before |
1178 | /// reporting lock failure. Zero value means try to get lock only |
1179 | /// once. |
1180 | /// @returns errc::success if lock is successfully obtained, |
1181 | /// errc::no_lock_available if the file cannot be locked, or platform-specific |
1182 | /// error_code otherwise. |
1183 | /// |
1184 | /// @note Care should be taken when using this function in a multithreaded |
1185 | /// context, as it may not prevent other threads in the same process from |
1186 | /// obtaining a lock on the same file, even if they are using a different file |
1187 | /// descriptor. |
1188 | std::error_code |
1189 | tryLockFile(int FD, |
1190 | std::chrono::milliseconds Timeout = std::chrono::milliseconds(0)); |
1191 | |
1192 | /// Lock the file. |
1193 | /// |
1194 | /// This function acts as @ref tryLockFile but it waits infinitely. |
1195 | std::error_code lockFile(int FD); |
1196 | |
1197 | /// Unlock the file. |
1198 | /// |
1199 | /// @param FD The descriptor representing the file to unlock. |
1200 | /// @returns errc::success if lock is successfully released or platform-specific |
1201 | /// error_code otherwise. |
1202 | std::error_code unlockFile(int FD); |
1203 | |
1204 | /// @brief Close the file object. This should be used instead of ::close for |
1205 | /// portability. On error, the caller should assume the file is closed, as is |
1206 | /// the case for Process::SafelyCloseFileDescriptor |
1207 | /// |
1208 | /// @param F On input, this is the file to close. On output, the file is |
1209 | /// set to kInvalidFile. |
1210 | /// |
1211 | /// @returns An error code if closing the file failed. Typically, an error here |
1212 | /// means that the filesystem may have failed to perform some buffered writes. |
1213 | std::error_code closeFile(file_t &F); |
1214 | |
1215 | #ifdef LLVM_ON_UNIX |
1216 | /// @brief Change ownership of a file. |
1217 | /// |
1218 | /// @param Owner The owner of the file to change to. |
1219 | /// @param Group The group of the file to change to. |
1220 | /// @returns errc::success if successfully updated file ownership, otherwise an |
1221 | /// error code is returned. |
1222 | std::error_code changeFileOwnership(int FD, uint32_t Owner, uint32_t Group); |
1223 | #endif |
1224 | |
1225 | /// RAII class that facilitates file locking. |
1226 | class FileLocker { |
1227 | int FD; ///< Locked file handle. |
1228 | FileLocker(int FD) : FD(FD) {} |
1229 | friend class llvm::raw_fd_ostream; |
1230 | |
1231 | public: |
1232 | FileLocker(const FileLocker &L) = delete; |
1233 | FileLocker(FileLocker &&L) : FD(L.FD) { L.FD = -1; } |
1234 | ~FileLocker() { |
1235 | if (FD != -1) |
1236 | unlockFile(FD); |
1237 | } |
1238 | FileLocker &operator=(FileLocker &&L) { |
1239 | FD = L.FD; |
1240 | L.FD = -1; |
1241 | return *this; |
1242 | } |
1243 | FileLocker &operator=(const FileLocker &L) = delete; |
1244 | std::error_code unlock() { |
1245 | if (FD != -1) { |
1246 | std::error_code Result = unlockFile(FD); |
1247 | FD = -1; |
1248 | return Result; |
1249 | } |
1250 | return std::error_code(); |
1251 | } |
1252 | }; |
1253 | |
1254 | std::error_code getUniqueID(const Twine Path, UniqueID &Result); |
1255 | |
1256 | /// Get disk space usage information. |
1257 | /// |
1258 | /// Note: Users must be careful about "Time Of Check, Time Of Use" kind of bug. |
1259 | /// Note: Windows reports results according to the quota allocated to the user. |
1260 | /// |
1261 | /// @param Path Input path. |
1262 | /// @returns a space_info structure filled with the capacity, free, and |
1263 | /// available space on the device \a Path is on. A platform specific error_code |
1264 | /// is returned on error. |
1265 | ErrorOr<space_info> disk_space(const Twine &Path); |
1266 | |
1267 | /// This class represents a memory mapped file. It is based on |
1268 | /// boost::iostreams::mapped_file. |
1269 | class mapped_file_region { |
1270 | public: |
1271 | enum mapmode { |
1272 | readonly, ///< May only access map via const_data as read only. |
1273 | readwrite, ///< May access map via data and modify it. Written to path. |
1274 | priv ///< May modify via data, but changes are lost on destruction. |
1275 | }; |
1276 | |
1277 | private: |
1278 | /// Platform-specific mapping state. |
1279 | size_t Size = 0; |
1280 | void *Mapping = nullptr; |
1281 | #ifdef _WIN32 |
1282 | sys::fs::file_t FileHandle = nullptr; |
1283 | #endif |
1284 | mapmode Mode = readonly; |
1285 | |
1286 | void copyFrom(const mapped_file_region &Copied) { |
1287 | Size = Copied.Size; |
1288 | Mapping = Copied.Mapping; |
1289 | #ifdef _WIN32 |
1290 | FileHandle = Copied.FileHandle; |
1291 | #endif |
1292 | Mode = Copied.Mode; |
1293 | } |
1294 | |
1295 | void moveFromImpl(mapped_file_region &Moved) { |
1296 | copyFrom(Copied: Moved); |
1297 | Moved.copyFrom(Copied: mapped_file_region()); |
1298 | } |
1299 | |
1300 | void unmapImpl(); |
1301 | void dontNeedImpl(); |
1302 | |
1303 | std::error_code init(sys::fs::file_t FD, uint64_t Offset, mapmode Mode); |
1304 | |
1305 | public: |
1306 | mapped_file_region() = default; |
1307 | mapped_file_region(mapped_file_region &&Moved) { moveFromImpl(Moved); } |
1308 | mapped_file_region &operator=(mapped_file_region &&Moved) { |
1309 | unmap(); |
1310 | moveFromImpl(Moved); |
1311 | return *this; |
1312 | } |
1313 | |
1314 | mapped_file_region(const mapped_file_region &) = delete; |
1315 | mapped_file_region &operator=(const mapped_file_region &) = delete; |
1316 | |
1317 | /// \param fd An open file descriptor to map. Does not take ownership of fd. |
1318 | mapped_file_region(sys::fs::file_t fd, mapmode mode, size_t length, uint64_t offset, |
1319 | std::error_code &ec); |
1320 | |
1321 | ~mapped_file_region() { unmapImpl(); } |
1322 | |
1323 | /// Check if this is a valid mapping. |
1324 | explicit operator bool() const { return Mapping; } |
1325 | |
1326 | /// Unmap. |
1327 | void unmap() { |
1328 | unmapImpl(); |
1329 | copyFrom(Copied: mapped_file_region()); |
1330 | } |
1331 | void dontNeed() { dontNeedImpl(); } |
1332 | |
1333 | size_t size() const; |
1334 | char *data() const; |
1335 | |
1336 | /// Get a const view of the data. Modifying this memory has undefined |
1337 | /// behavior. |
1338 | const char *const_data() const; |
1339 | |
1340 | /// \returns The minimum alignment offset must be. |
1341 | static int alignment(); |
1342 | }; |
1343 | |
1344 | /// Return the path to the main executable, given the value of argv[0] from |
1345 | /// program startup and the address of main itself. In extremis, this function |
1346 | /// may fail and return an empty path. |
1347 | std::string getMainExecutable(const char *argv0, void *MainExecAddr); |
1348 | |
1349 | /// @} |
1350 | /// @name Iterators |
1351 | /// @{ |
1352 | |
1353 | /// directory_entry - A single entry in a directory. |
1354 | class directory_entry { |
1355 | // FIXME: different platforms make different information available "for free" |
1356 | // when traversing a directory. The design of this class wraps most of the |
1357 | // information in basic_file_status, so on platforms where we can't populate |
1358 | // that whole structure, callers end up paying for a stat(). |
1359 | // std::filesystem::directory_entry may be a better model. |
1360 | std::string Path; |
1361 | file_type Type = file_type::type_unknown; // Most platforms can provide this. |
1362 | bool FollowSymlinks = true; // Affects the behavior of status(). |
1363 | basic_file_status Status; // If available. |
1364 | |
1365 | public: |
1366 | explicit directory_entry(const Twine &Path, bool FollowSymlinks = true, |
1367 | file_type Type = file_type::type_unknown, |
1368 | basic_file_status Status = basic_file_status()) |
1369 | : Path(Path.str()), Type(Type), FollowSymlinks(FollowSymlinks), |
1370 | Status(Status) {} |
1371 | |
1372 | directory_entry() = default; |
1373 | |
1374 | void replace_filename(const Twine &Filename, file_type Type, |
1375 | basic_file_status Status = basic_file_status()); |
1376 | |
1377 | const std::string &path() const { return Path; } |
1378 | // Get basic information about entry file (a subset of fs::status()). |
1379 | // On most platforms this is a stat() call. |
1380 | // On windows the information was already retrieved from the directory. |
1381 | ErrorOr<basic_file_status> status() const; |
1382 | // Get the type of this file. |
1383 | // On most platforms (Linux/Mac/Windows/BSD), this was already retrieved. |
1384 | // On some platforms (e.g. Solaris) this is a stat() call. |
1385 | file_type type() const { |
1386 | if (Type != file_type::type_unknown) |
1387 | return Type; |
1388 | auto S = status(); |
1389 | return S ? S->type() : file_type::type_unknown; |
1390 | } |
1391 | |
1392 | bool operator==(const directory_entry& RHS) const { return Path == RHS.Path; } |
1393 | bool operator!=(const directory_entry& RHS) const { return !(*this == RHS); } |
1394 | bool operator< (const directory_entry& RHS) const; |
1395 | bool operator<=(const directory_entry& RHS) const; |
1396 | bool operator> (const directory_entry& RHS) const; |
1397 | bool operator>=(const directory_entry& RHS) const; |
1398 | }; |
1399 | |
1400 | namespace detail { |
1401 | |
1402 | struct DirIterState; |
1403 | |
1404 | std::error_code directory_iterator_construct(DirIterState &, StringRef, bool); |
1405 | std::error_code directory_iterator_increment(DirIterState &); |
1406 | std::error_code directory_iterator_destruct(DirIterState &); |
1407 | |
1408 | /// Keeps state for the directory_iterator. |
1409 | struct DirIterState { |
1410 | ~DirIterState() { |
1411 | directory_iterator_destruct(*this); |
1412 | } |
1413 | |
1414 | intptr_t IterationHandle = 0; |
1415 | directory_entry CurrentEntry; |
1416 | }; |
1417 | |
1418 | } // end namespace detail |
1419 | |
1420 | /// directory_iterator - Iterates through the entries in path. There is no |
1421 | /// operator++ because we need an error_code. If it's really needed we can make |
1422 | /// it call report_fatal_error on error. |
1423 | class directory_iterator { |
1424 | std::shared_ptr<detail::DirIterState> State; |
1425 | bool FollowSymlinks = true; |
1426 | |
1427 | public: |
1428 | explicit directory_iterator(const Twine &path, std::error_code &ec, |
1429 | bool follow_symlinks = true) |
1430 | : FollowSymlinks(follow_symlinks) { |
1431 | State = std::make_shared<detail::DirIterState>(); |
1432 | SmallString<128> path_storage; |
1433 | ec = detail::directory_iterator_construct( |
1434 | *State, path.toStringRef(Out&: path_storage), FollowSymlinks); |
1435 | } |
1436 | |
1437 | explicit directory_iterator(const directory_entry &de, std::error_code &ec, |
1438 | bool follow_symlinks = true) |
1439 | : FollowSymlinks(follow_symlinks) { |
1440 | State = std::make_shared<detail::DirIterState>(); |
1441 | ec = detail::directory_iterator_construct( |
1442 | *State, de.path(), FollowSymlinks); |
1443 | } |
1444 | |
1445 | /// Construct end iterator. |
1446 | directory_iterator() = default; |
1447 | |
1448 | // No operator++ because we need error_code. |
1449 | directory_iterator &increment(std::error_code &ec) { |
1450 | ec = directory_iterator_increment(*State); |
1451 | return *this; |
1452 | } |
1453 | |
1454 | const directory_entry &operator*() const { return State->CurrentEntry; } |
1455 | const directory_entry *operator->() const { return &State->CurrentEntry; } |
1456 | |
1457 | bool operator==(const directory_iterator &RHS) const { |
1458 | if (State == RHS.State) |
1459 | return true; |
1460 | if (!RHS.State) |
1461 | return State->CurrentEntry == directory_entry(); |
1462 | if (!State) |
1463 | return RHS.State->CurrentEntry == directory_entry(); |
1464 | return State->CurrentEntry == RHS.State->CurrentEntry; |
1465 | } |
1466 | |
1467 | bool operator!=(const directory_iterator &RHS) const { |
1468 | return !(*this == RHS); |
1469 | } |
1470 | }; |
1471 | |
1472 | namespace detail { |
1473 | |
1474 | /// Keeps state for the recursive_directory_iterator. |
1475 | struct RecDirIterState { |
1476 | std::stack<directory_iterator, std::vector<directory_iterator>> Stack; |
1477 | uint16_t Level = 0; |
1478 | bool HasNoPushRequest = false; |
1479 | }; |
1480 | |
1481 | } // end namespace detail |
1482 | |
1483 | /// recursive_directory_iterator - Same as directory_iterator except for it |
1484 | /// recurses down into child directories. |
1485 | class recursive_directory_iterator { |
1486 | std::shared_ptr<detail::RecDirIterState> State; |
1487 | bool Follow; |
1488 | |
1489 | public: |
1490 | recursive_directory_iterator() = default; |
1491 | explicit recursive_directory_iterator(const Twine &path, std::error_code &ec, |
1492 | bool follow_symlinks = true) |
1493 | : State(std::make_shared<detail::RecDirIterState>()), |
1494 | Follow(follow_symlinks) { |
1495 | State->Stack.push(x: directory_iterator(path, ec, Follow)); |
1496 | if (State->Stack.top() == directory_iterator()) |
1497 | State.reset(); |
1498 | } |
1499 | |
1500 | // No operator++ because we need error_code. |
1501 | recursive_directory_iterator &increment(std::error_code &ec) { |
1502 | const directory_iterator end_itr = {}; |
1503 | |
1504 | if (State->HasNoPushRequest) |
1505 | State->HasNoPushRequest = false; |
1506 | else { |
1507 | file_type type = State->Stack.top()->type(); |
1508 | if (type == file_type::symlink_file && Follow) { |
1509 | // Resolve the symlink: is it a directory to recurse into? |
1510 | ErrorOr<basic_file_status> status = State->Stack.top()->status(); |
1511 | if (status) |
1512 | type = status->type(); |
1513 | // Otherwise broken symlink, and we'll continue. |
1514 | } |
1515 | if (type == file_type::directory_file) { |
1516 | State->Stack.push(x: directory_iterator(*State->Stack.top(), ec, Follow)); |
1517 | if (State->Stack.top() != end_itr) { |
1518 | ++State->Level; |
1519 | return *this; |
1520 | } |
1521 | State->Stack.pop(); |
1522 | } |
1523 | } |
1524 | |
1525 | while (!State->Stack.empty() |
1526 | && State->Stack.top().increment(ec) == end_itr) { |
1527 | State->Stack.pop(); |
1528 | --State->Level; |
1529 | } |
1530 | |
1531 | // Check if we are done. If so, create an end iterator. |
1532 | if (State->Stack.empty()) |
1533 | State.reset(); |
1534 | |
1535 | return *this; |
1536 | } |
1537 | |
1538 | const directory_entry &operator*() const { return *State->Stack.top(); } |
1539 | const directory_entry *operator->() const { return &*State->Stack.top(); } |
1540 | |
1541 | // observers |
1542 | /// Gets the current level. Starting path is at level 0. |
1543 | int level() const { return State->Level; } |
1544 | |
1545 | /// Returns true if no_push has been called for this directory_entry. |
1546 | bool no_push_request() const { return State->HasNoPushRequest; } |
1547 | |
1548 | // modifiers |
1549 | /// Goes up one level if Level > 0. |
1550 | void pop() { |
1551 | assert(State && "Cannot pop an end iterator!" ); |
1552 | assert(State->Level > 0 && "Cannot pop an iterator with level < 1" ); |
1553 | |
1554 | const directory_iterator end_itr = {}; |
1555 | std::error_code ec; |
1556 | do { |
1557 | if (ec) |
1558 | report_fatal_error(reason: "Error incrementing directory iterator." ); |
1559 | State->Stack.pop(); |
1560 | --State->Level; |
1561 | } while (!State->Stack.empty() |
1562 | && State->Stack.top().increment(ec) == end_itr); |
1563 | |
1564 | // Check if we are done. If so, create an end iterator. |
1565 | if (State->Stack.empty()) |
1566 | State.reset(); |
1567 | } |
1568 | |
1569 | /// Does not go down into the current directory_entry. |
1570 | void no_push() { State->HasNoPushRequest = true; } |
1571 | |
1572 | bool operator==(const recursive_directory_iterator &RHS) const { |
1573 | return State == RHS.State; |
1574 | } |
1575 | |
1576 | bool operator!=(const recursive_directory_iterator &RHS) const { |
1577 | return !(*this == RHS); |
1578 | } |
1579 | }; |
1580 | |
1581 | /// @} |
1582 | |
1583 | } // end namespace fs |
1584 | } // end namespace sys |
1585 | } // end namespace llvm |
1586 | |
1587 | #endif // LLVM_SUPPORT_FILESYSTEM_H |
1588 | |