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 uint32_t FileIndexHigh = 0;
237 uint32_t FileIndexLow = 0;
238 #endif
239
240public:
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.
284void make_absolute(const Twine &current_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.
297std::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.
305std::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.
315std::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.
329std::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.
337std::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.
346std::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.
353void 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.
360std::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.
367std::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.
375std::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.
382std::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.
392std::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.
398std::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.
404std::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.
412std::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.
418inline 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.
434ErrorOr<MD5::MD5Result> md5_contents(int FD);
435
436/// Version of compute_md5 that doesn't require an open file descriptor.
437ErrorOr<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.
448bool exists(const basic_file_status &status);
449
450enum 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.
457std::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.
463inline bool exists(const Twine &Path) {
464 return !access(Path, 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.
471bool 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.
477inline bool can_write(const Twine &Path) {
478 return !access(Path, 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.
490bool 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.
502std::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.
506inline 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.
518std::error_code is_local(const Twine &path, bool &result);
519
520/// Version of is_local accepting an open file descriptor.
521std::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.
525inline bool is_local(const Twine &Path) {
526 bool Result;
527 return !is_local(Path, 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.
532inline bool is_local(int FD) {
533 bool Result;
534 return !is_local(FD, 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.
543file_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.
549bool 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.
558std::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.
562inline bool is_directory(const Twine &Path) {
563 bool Result;
564 return !is_directory(Path, 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.
571bool 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.
580std::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.
584inline bool is_regular_file(const Twine &Path) {
585 bool Result;
586 if (is_regular_file(Path, 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.
595bool 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.
604std::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.
608inline bool is_symlink_file(const Twine &Path) {
609 bool Result;
610 if (is_symlink_file(Path, 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)
620bool 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.
630std::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.
640std::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.
644std::error_code status(int FD, file_status &Result);
645
646#ifdef _WIN32
647/// A version for when a file descriptor is already available.
648std::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.
657unsigned 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.
668std::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.
673std::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.
683ErrorOr<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.
691inline std::error_code file_size(const Twine &Path, uint64_t &Result) {
692 file_status Status;
693 std::error_code EC = status(Path, 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.
705std::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.
710inline std::error_code setLastAccessAndModificationTime(int FD,
711 TimePoint<> Time) {
712 return setLastAccessAndModificationTime(FD, Time, Time);
713}
714
715/// Is status available?
716///
717/// @param s Input file status.
718/// @returns True if status() != status_error.
719bool 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.
727std::error_code status_known(const Twine &path, bool &result);
728
729enum 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
751enum FileAccess : unsigned {
752 FA_Read = 1,
753 FA_Write = 2,
754};
755
756enum 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.
806void 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.
832std::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.
839std::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.
850class TempFile {
851 bool Done = false;
852 TempFile(StringRef Name, int FD);
853
854public:
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 ExtraFlags = 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.
895std::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.
902std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
903 SmallVectorImpl<char> &ResultPath,
904 OpenFlags Flags = OF_None);
905
906std::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.
916std::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.
927std::error_code
928getPotentiallyUniqueTempFileName(const Twine &Prefix, StringRef Suffix,
929 SmallVectorImpl<char> &ResultPath);
930
931inline OpenFlags operator|(OpenFlags A, OpenFlags B) {
932 return OpenFlags(unsigned(A) | unsigned(B));
933}
934
935inline OpenFlags &operator|=(OpenFlags &A, OpenFlags B) {
936 A = A | B;
937 return A;
938}
939
940inline FileAccess operator|(FileAccess A, FileAccess B) {
941 return FileAccess(unsigned(A) | unsigned(B));
942}
943
944inline 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.
965std::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.
983Expected<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.
990file_t convertFDToNativeFile(int FD);
991
992#ifndef _WIN32
993inline 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.
998file_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.
1002file_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.
1006file_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.
1015Expected<size_t> readNativeFile(file_t FileHandle, MutableArrayRef<char> Buf);
1016
1017/// Default chunk size for \a readNativeFileToEOF().
1018enum : 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.
1033Error 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.
1045Expected<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.
1064inline std::error_code
1065openFileForWrite(const Twine &Name, int &ResultFD,
1066 CreationDisposition Disp = CD_CreateAlways,
1067 OpenFlags Flags = OF_None, unsigned Mode = 0666) {
1068 return openFile(Name, ResultFD, Disp, 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.
1084inline Expected<file_t> openNativeFileForWrite(const Twine &Name,
1085 CreationDisposition Disp,
1086 OpenFlags Flags,
1087 unsigned Mode = 0666) {
1088 return openNativeFile(Name, Disp, 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.
1106inline 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, 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.
1126inline Expected<file_t> openNativeFileForReadWrite(const Twine &Name,
1127 CreationDisposition Disp,
1128 OpenFlags Flags,
1129 unsigned Mode = 0666) {
1130 return openNativeFile(Name, Disp, 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.
1147std::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.
1163Expected<file_t>
1164openNativeFileForRead(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.
1188std::error_code
1189tryLockFile(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.
1195std::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.
1202std::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.
1213std::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.
1222std::error_code changeFileOwnership(int FD, uint32_t Owner, uint32_t Group);
1223#endif
1224
1225/// RAII class that facilitates file locking.
1226class FileLocker {
1227 int FD; ///< Locked file handle.
1228 FileLocker(int FD) : FD(FD) {}
1229 friend class llvm::raw_fd_ostream;
1230
1231public:
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
1254std::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.
1265ErrorOr<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.
1269class mapped_file_region {
1270public:
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
1277private:
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(Moved);
1297 Moved.copyFrom(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
1305public:
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(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.
1347std::string getMainExecutable(const char *argv0, void *MainExecAddr);
1348
1349/// @}
1350/// @name Iterators
1351/// @{
1352
1353/// directory_entry - A single entry in a directory.
1354class 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
1365public:
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
1400namespace 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.
1423class directory_iterator {
1424 std::shared_ptr<detail::DirIterState> State;
1425 bool FollowSymlinks = true;
1426
1427public:
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(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
1472namespace 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.
1485class recursive_directory_iterator {
1486 std::shared_ptr<detail::RecDirIterState> State;
1487 bool Follow;
1488
1489public:
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(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(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("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

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