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

source code of llvm/include/llvm/Support/FileSystem.h