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 F_None = 0, // For compatibility
759
760 /// The file should be opened in text mode on platforms like z/OS that make
761 /// this distinction.
762 OF_Text = 1,
763 F_Text = 1, // For compatibility
764
765 /// The file should use a carriage linefeed '\r\n'. This flag should only be
766 /// used with OF_Text. Only makes a difference on Windows.
767 OF_CRLF = 2,
768
769 /// The file should be opened in text mode and use a carriage linefeed '\r\n'.
770 /// This flag has the same functionality as OF_Text on z/OS but adds a
771 /// carriage linefeed on Windows.
772 OF_TextWithCRLF = OF_Text | OF_CRLF,
773
774 /// The file should be opened in append mode.
775 OF_Append = 4,
776 F_Append = 4, // For compatibility
777
778 /// Delete the file on close. Only makes a difference on windows.
779 OF_Delete = 8,
780
781 /// When a child process is launched, this file should remain open in the
782 /// child process.
783 OF_ChildInherit = 16,
784
785 /// Force files Atime to be updated on access. Only makes a difference on
786 /// Windows.
787 OF_UpdateAtime = 32,
788};
789
790/// Create a potentially unique file name but does not create it.
791///
792/// Generates a unique path suitable for a temporary file but does not
793/// open or create the file. The name is based on \a Model with '%'
794/// replaced by a random char in [0-9a-f]. If \a MakeAbsolute is true
795/// then the system's temp directory is prepended first. If \a MakeAbsolute
796/// is false the current directory will be used instead.
797///
798/// This function does not check if the file exists. If you want to be sure
799/// that the file does not yet exist, you should use use enough '%' characters
800/// in your model to ensure this. Each '%' gives 4-bits of entropy so you can
801/// use 32 of them to get 128 bits of entropy.
802///
803/// Example: clang-%%-%%-%%-%%-%%.s => clang-a0-b1-c2-d3-e4.s
804///
805/// @param Model Name to base unique path off of.
806/// @param ResultPath Set to the file's path.
807/// @param MakeAbsolute Whether to use the system temp directory.
808void createUniquePath(const Twine &Model, SmallVectorImpl<char> &ResultPath,
809 bool MakeAbsolute);
810
811/// Create a uniquely named file.
812///
813/// Generates a unique path suitable for a temporary file and then opens it as a
814/// file. The name is based on \a Model with '%' replaced by a random char in
815/// [0-9a-f]. If \a Model is not an absolute path, the temporary file will be
816/// created in the current directory.
817///
818/// Example: clang-%%-%%-%%-%%-%%.s => clang-a0-b1-c2-d3-e4.s
819///
820/// This is an atomic operation. Either the file is created and opened, or the
821/// file system is left untouched.
822///
823/// The intended use is for files that are to be kept, possibly after
824/// renaming them. For example, when running 'clang -c foo.o', the file can
825/// be first created as foo-abc123.o and then renamed.
826///
827/// @param Model Name to base unique path off of.
828/// @param ResultFD Set to the opened file's file descriptor.
829/// @param ResultPath Set to the opened file's absolute path.
830/// @param Flags Set to the opened file's flags.
831/// @param Mode Set to the opened file's permissions.
832/// @returns errc::success if Result{FD,Path} have been successfully set,
833/// otherwise a platform-specific error_code.
834std::error_code createUniqueFile(const Twine &Model, int &ResultFD,
835 SmallVectorImpl<char> &ResultPath,
836 OpenFlags Flags = OF_None,
837 unsigned Mode = all_read | all_write);
838
839/// Simpler version for clients that don't want an open file. An empty
840/// file will still be created.
841std::error_code createUniqueFile(const Twine &Model,
842 SmallVectorImpl<char> &ResultPath,
843 unsigned Mode = all_read | all_write);
844
845/// Represents a temporary file.
846///
847/// The temporary file must be eventually discarded or given a final name and
848/// kept.
849///
850/// The destructor doesn't implicitly discard because there is no way to
851/// properly handle errors in a destructor.
852class TempFile {
853 bool Done = false;
854 TempFile(StringRef Name, int FD);
855
856public:
857 /// This creates a temporary file with createUniqueFile and schedules it for
858 /// deletion with sys::RemoveFileOnSignal.
859 static Expected<TempFile> create(const Twine &Model,
860 unsigned Mode = all_read | all_write);
861 TempFile(TempFile &&Other);
862 TempFile &operator=(TempFile &&Other);
863
864 // Name of the temporary file.
865 std::string TmpName;
866
867 // The open file descriptor.
868 int FD = -1;
869
870 // Keep this with the given name.
871 Error keep(const Twine &Name);
872
873 // Keep this with the temporary name.
874 Error keep();
875
876 // Delete the file.
877 Error discard();
878
879 // This checks that keep or delete was called.
880 ~TempFile();
881};
882
883/// Create a file in the system temporary directory.
884///
885/// The filename is of the form prefix-random_chars.suffix. Since the directory
886/// is not know to the caller, Prefix and Suffix cannot have path separators.
887/// The files are created with mode 0600.
888///
889/// This should be used for things like a temporary .s that is removed after
890/// running the assembler.
891std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
892 int &ResultFD,
893 SmallVectorImpl<char> &ResultPath,
894 OpenFlags Flags = OF_None);
895
896/// Simpler version for clients that don't want an open file. An empty
897/// file will still be created.
898std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
899 SmallVectorImpl<char> &ResultPath,
900 OpenFlags Flags = OF_None);
901
902std::error_code createUniqueDirectory(const Twine &Prefix,
903 SmallVectorImpl<char> &ResultPath);
904
905/// Get a unique name, not currently exisiting in the filesystem. Subject
906/// to race conditions, prefer to use createUniqueFile instead.
907///
908/// Similar to createUniqueFile, but instead of creating a file only
909/// checks if it exists. This function is subject to race conditions, if you
910/// want to use the returned name to actually create a file, use
911/// createUniqueFile instead.
912std::error_code getPotentiallyUniqueFileName(const Twine &Model,
913 SmallVectorImpl<char> &ResultPath);
914
915/// Get a unique temporary file name, not currently exisiting in the
916/// filesystem. Subject to race conditions, prefer to use createTemporaryFile
917/// instead.
918///
919/// Similar to createTemporaryFile, but instead of creating a file only
920/// checks if it exists. This function is subject to race conditions, if you
921/// want to use the returned name to actually create a file, use
922/// createTemporaryFile instead.
923std::error_code
924getPotentiallyUniqueTempFileName(const Twine &Prefix, StringRef Suffix,
925 SmallVectorImpl<char> &ResultPath);
926
927inline OpenFlags operator|(OpenFlags A, OpenFlags B) {
928 return OpenFlags(unsigned(A) | unsigned(B));
929}
930
931inline OpenFlags &operator|=(OpenFlags &A, OpenFlags B) {
932 A = A | B;
933 return A;
934}
935
936inline FileAccess operator|(FileAccess A, FileAccess B) {
937 return FileAccess(unsigned(A) | unsigned(B));
938}
939
940inline FileAccess &operator|=(FileAccess &A, FileAccess B) {
941 A = A | B;
942 return A;
943}
944
945/// @brief Opens a file with the specified creation disposition, access mode,
946/// and flags and returns a file descriptor.
947///
948/// The caller is responsible for closing the file descriptor once they are
949/// finished with it.
950///
951/// @param Name The path of the file to open, relative or absolute.
952/// @param ResultFD If the file could be opened successfully, its descriptor
953/// is stored in this location. Otherwise, this is set to -1.
954/// @param Disp Value specifying the existing-file behavior.
955/// @param Access Value specifying whether to open the file in read, write, or
956/// read-write mode.
957/// @param Flags Additional flags.
958/// @param Mode The access permissions of the file, represented in octal.
959/// @returns errc::success if \a Name has been opened, otherwise a
960/// platform-specific error_code.
961std::error_code openFile(const Twine &Name, int &ResultFD,
962 CreationDisposition Disp, FileAccess Access,
963 OpenFlags Flags, unsigned Mode = 0666);
964
965/// @brief Opens a file with the specified creation disposition, access mode,
966/// and flags and returns a platform-specific file object.
967///
968/// The caller is responsible for closing the file object once they are
969/// finished with it.
970///
971/// @param Name The path of the file to open, relative or absolute.
972/// @param Disp Value specifying the existing-file behavior.
973/// @param Access Value specifying whether to open the file in read, write, or
974/// read-write mode.
975/// @param Flags Additional flags.
976/// @param Mode The access permissions of the file, represented in octal.
977/// @returns errc::success if \a Name has been opened, otherwise a
978/// platform-specific error_code.
979Expected<file_t> openNativeFile(const Twine &Name, CreationDisposition Disp,
980 FileAccess Access, OpenFlags Flags,
981 unsigned Mode = 0666);
982
983/// Converts from a Posix file descriptor number to a native file handle.
984/// On Windows, this retreives the underlying handle. On non-Windows, this is a
985/// no-op.
986file_t convertFDToNativeFile(int FD);
987
988#ifndef _WIN32
989inline file_t convertFDToNativeFile(int FD) { return FD; }
990#endif
991
992/// Return an open handle to standard in. On Unix, this is typically FD 0.
993/// Returns kInvalidFile when the stream is closed.
994file_t getStdinHandle();
995
996/// Return an open handle to standard out. On Unix, this is typically FD 1.
997/// Returns kInvalidFile when the stream is closed.
998file_t getStdoutHandle();
999
1000/// Return an open handle to standard error. On Unix, this is typically FD 2.
1001/// Returns kInvalidFile when the stream is closed.
1002file_t getStderrHandle();
1003
1004/// Reads \p Buf.size() bytes from \p FileHandle into \p Buf. Returns the number
1005/// of bytes actually read. On Unix, this is equivalent to `return ::read(FD,
1006/// Buf.data(), Buf.size())`, with error reporting. Returns 0 when reaching EOF.
1007///
1008/// @param FileHandle File to read from.
1009/// @param Buf Buffer to read into.
1010/// @returns The number of bytes read, or error.
1011Expected<size_t> readNativeFile(file_t FileHandle, MutableArrayRef<char> Buf);
1012
1013/// Reads \p Buf.size() bytes from \p FileHandle at offset \p Offset into \p
1014/// Buf. If 'pread' is available, this will use that, otherwise it will use
1015/// 'lseek'. Returns the number of bytes actually read. Returns 0 when reaching
1016/// EOF.
1017///
1018/// @param FileHandle File to read from.
1019/// @param Buf Buffer to read into.
1020/// @param Offset Offset into the file at which the read should occur.
1021/// @returns The number of bytes read, or error.
1022Expected<size_t> readNativeFileSlice(file_t FileHandle,
1023 MutableArrayRef<char> Buf,
1024 uint64_t Offset);
1025
1026/// @brief Opens the file with the given name in a write-only or read-write
1027/// mode, returning its open file descriptor. If the file does not exist, it
1028/// is created.
1029///
1030/// The caller is responsible for closing the file descriptor once they are
1031/// finished with it.
1032///
1033/// @param Name The path of the file to open, relative or absolute.
1034/// @param ResultFD If the file could be opened successfully, its descriptor
1035/// is stored in this location. Otherwise, this is set to -1.
1036/// @param Flags Additional flags used to determine whether the file should be
1037/// opened in, for example, read-write or in write-only mode.
1038/// @param Mode The access permissions of the file, represented in octal.
1039/// @returns errc::success if \a Name has been opened, otherwise a
1040/// platform-specific error_code.
1041inline std::error_code
1042openFileForWrite(const Twine &Name, int &ResultFD,
1043 CreationDisposition Disp = CD_CreateAlways,
1044 OpenFlags Flags = OF_None, unsigned Mode = 0666) {
1045 return openFile(Name, ResultFD, Disp, FA_Write, Flags, Mode);
1046}
1047
1048/// @brief Opens the file with the given name in a write-only or read-write
1049/// mode, returning its open file descriptor. If the file does not exist, it
1050/// is created.
1051///
1052/// The caller is responsible for closing the freeing the file once they are
1053/// finished with it.
1054///
1055/// @param Name The path of the file to open, relative or absolute.
1056/// @param Flags Additional flags used to determine whether the file should be
1057/// opened in, for example, read-write or in write-only mode.
1058/// @param Mode The access permissions of the file, represented in octal.
1059/// @returns a platform-specific file descriptor if \a Name has been opened,
1060/// otherwise an error object.
1061inline Expected<file_t> openNativeFileForWrite(const Twine &Name,
1062 CreationDisposition Disp,
1063 OpenFlags Flags,
1064 unsigned Mode = 0666) {
1065 return openNativeFile(Name, Disp, FA_Write, Flags, Mode);
1066}
1067
1068/// @brief Opens the file with the given name in a write-only or read-write
1069/// mode, returning its open file descriptor. If the file does not exist, it
1070/// is created.
1071///
1072/// The caller is responsible for closing the file descriptor once they are
1073/// finished with it.
1074///
1075/// @param Name The path of the file to open, relative or absolute.
1076/// @param ResultFD If the file could be opened successfully, its descriptor
1077/// is stored in this location. Otherwise, this is set to -1.
1078/// @param Flags Additional flags used to determine whether the file should be
1079/// opened in, for example, read-write or in write-only mode.
1080/// @param Mode The access permissions of the file, represented in octal.
1081/// @returns errc::success if \a Name has been opened, otherwise a
1082/// platform-specific error_code.
1083inline std::error_code openFileForReadWrite(const Twine &Name, int &ResultFD,
1084 CreationDisposition Disp,
1085 OpenFlags Flags,
1086 unsigned Mode = 0666) {
1087 return openFile(Name, ResultFD, Disp, FA_Write | FA_Read, Flags, Mode);
1088}
1089
1090/// @brief Opens the file with the given name in a write-only or read-write
1091/// mode, returning its open file descriptor. If the file does not exist, it
1092/// is created.
1093///
1094/// The caller is responsible for closing the freeing the file once they are
1095/// finished with it.
1096///
1097/// @param Name The path of the file to open, relative or absolute.
1098/// @param Flags Additional flags used to determine whether the file should be
1099/// opened in, for example, read-write or in write-only mode.
1100/// @param Mode The access permissions of the file, represented in octal.
1101/// @returns a platform-specific file descriptor if \a Name has been opened,
1102/// otherwise an error object.
1103inline Expected<file_t> openNativeFileForReadWrite(const Twine &Name,
1104 CreationDisposition Disp,
1105 OpenFlags Flags,
1106 unsigned Mode = 0666) {
1107 return openNativeFile(Name, Disp, FA_Write | FA_Read, Flags, Mode);
1108}
1109
1110/// @brief Opens the file with the given name in a read-only mode, returning
1111/// its open file descriptor.
1112///
1113/// The caller is responsible for closing the file descriptor once they are
1114/// finished with it.
1115///
1116/// @param Name The path of the file to open, relative or absolute.
1117/// @param ResultFD If the file could be opened successfully, its descriptor
1118/// is stored in this location. Otherwise, this is set to -1.
1119/// @param RealPath If nonnull, extra work is done to determine the real path
1120/// of the opened file, and that path is stored in this
1121/// location.
1122/// @returns errc::success if \a Name has been opened, otherwise a
1123/// platform-specific error_code.
1124std::error_code openFileForRead(const Twine &Name, int &ResultFD,
1125 OpenFlags Flags = OF_None,
1126 SmallVectorImpl<char> *RealPath = nullptr);
1127
1128/// @brief Opens the file with the given name in a read-only mode, returning
1129/// its open file descriptor.
1130///
1131/// The caller is responsible for closing the freeing the file once they are
1132/// finished with it.
1133///
1134/// @param Name The path of the file to open, relative or absolute.
1135/// @param RealPath If nonnull, extra work is done to determine the real path
1136/// of the opened file, and that path is stored in this
1137/// location.
1138/// @returns a platform-specific file descriptor if \a Name has been opened,
1139/// otherwise an error object.
1140Expected<file_t>
1141openNativeFileForRead(const Twine &Name, OpenFlags Flags = OF_None,
1142 SmallVectorImpl<char> *RealPath = nullptr);
1143
1144/// Try to locks the file during the specified time.
1145///
1146/// This function implements advisory locking on entire file. If it returns
1147/// <em>errc::success</em>, the file is locked by the calling process. Until the
1148/// process unlocks the file by calling \a unlockFile, all attempts to lock the
1149/// same file will fail/block. The process that locked the file may assume that
1150/// none of other processes read or write this file, provided that all processes
1151/// lock the file prior to accessing its content.
1152///
1153/// @param FD The descriptor representing the file to lock.
1154/// @param Timeout Time in milliseconds that the process should wait before
1155/// reporting lock failure. Zero value means try to get lock only
1156/// once.
1157/// @returns errc::success if lock is successfully obtained,
1158/// errc::no_lock_available if the file cannot be locked, or platform-specific
1159/// error_code otherwise.
1160///
1161/// @note Care should be taken when using this function in a multithreaded
1162/// context, as it may not prevent other threads in the same process from
1163/// obtaining a lock on the same file, even if they are using a different file
1164/// descriptor.
1165std::error_code
1166tryLockFile(int FD,
1167 std::chrono::milliseconds Timeout = std::chrono::milliseconds(0));
1168
1169/// Lock the file.
1170///
1171/// This function acts as @ref tryLockFile but it waits infinitely.
1172std::error_code lockFile(int FD);
1173
1174/// Unlock the file.
1175///
1176/// @param FD The descriptor representing the file to unlock.
1177/// @returns errc::success if lock is successfully released or platform-specific
1178/// error_code otherwise.
1179std::error_code unlockFile(int FD);
1180
1181/// @brief Close the file object. This should be used instead of ::close for
1182/// portability. On error, the caller should assume the file is closed, as is
1183/// the case for Process::SafelyCloseFileDescriptor
1184///
1185/// @param F On input, this is the file to close. On output, the file is
1186/// set to kInvalidFile.
1187///
1188/// @returns An error code if closing the file failed. Typically, an error here
1189/// means that the filesystem may have failed to perform some buffered writes.
1190std::error_code closeFile(file_t &F);
1191
1192#ifdef LLVM_ON_UNIX
1193/// @brief Change ownership of a file.
1194///
1195/// @param Owner The owner of the file to change to.
1196/// @param Group The group of the file to change to.
1197/// @returns errc::success if successfully updated file ownership, otherwise an
1198/// error code is returned.
1199std::error_code changeFileOwnership(int FD, uint32_t Owner, uint32_t Group);
1200#endif
1201
1202/// RAII class that facilitates file locking.
1203class FileLocker {
1204 int FD; ///< Locked file handle.
1205 FileLocker(int FD) : FD(FD) {}
1206 friend class llvm::raw_fd_ostream;
1207
1208public:
1209 FileLocker(const FileLocker &L) = delete;
1210 FileLocker(FileLocker &&L) : FD(L.FD) { L.FD = -1; }
1211 ~FileLocker() {
1212 if (FD != -1)
1213 unlockFile(FD);
1214 }
1215 FileLocker &operator=(FileLocker &&L) {
1216 FD = L.FD;
1217 L.FD = -1;
1218 return *this;
1219 }
1220 FileLocker &operator=(const FileLocker &L) = delete;
1221 std::error_code unlock() {
1222 if (FD != -1) {
1223 std::error_code Result = unlockFile(FD);
1224 FD = -1;
1225 return Result;
1226 }
1227 return std::error_code();
1228 }
1229};
1230
1231std::error_code getUniqueID(const Twine Path, UniqueID &Result);
1232
1233/// Get disk space usage information.
1234///
1235/// Note: Users must be careful about "Time Of Check, Time Of Use" kind of bug.
1236/// Note: Windows reports results according to the quota allocated to the user.
1237///
1238/// @param Path Input path.
1239/// @returns a space_info structure filled with the capacity, free, and
1240/// available space on the device \a Path is on. A platform specific error_code
1241/// is returned on error.
1242ErrorOr<space_info> disk_space(const Twine &Path);
1243
1244/// This class represents a memory mapped file. It is based on
1245/// boost::iostreams::mapped_file.
1246class mapped_file_region {
1247public:
1248 enum mapmode {
1249 readonly, ///< May only access map via const_data as read only.
1250 readwrite, ///< May access map via data and modify it. Written to path.
1251 priv ///< May modify via data, but changes are lost on destruction.
1252 };
1253
1254private:
1255 /// Platform-specific mapping state.
1256 size_t Size = 0;
1257 void *Mapping = nullptr;
1258#ifdef _WIN32
1259 sys::fs::file_t FileHandle = nullptr;
1260#endif
1261 mapmode Mode = readonly;
1262
1263 void copyFrom(const mapped_file_region &Copied) {
1264 Size = Copied.Size;
1265 Mapping = Copied.Mapping;
1266#ifdef _WIN32
1267 FileHandle = Copied.FileHandle;
1268#endif
1269 Mode = Copied.Mode;
1270 }
1271
1272 void moveFromImpl(mapped_file_region &Moved) {
1273 copyFrom(Moved);
1274 Moved.copyFrom(mapped_file_region());
1275 }
1276
1277 void unmapImpl();
1278
1279 std::error_code init(sys::fs::file_t FD, uint64_t Offset, mapmode Mode);
1280
1281public:
1282 mapped_file_region() = default;
1283 mapped_file_region(mapped_file_region &&Moved) { moveFromImpl(Moved); }
1284 mapped_file_region &operator=(mapped_file_region &&Moved) {
1285 unmap();
1286 moveFromImpl(Moved);
1287 return *this;
1288 }
1289
1290 mapped_file_region(const mapped_file_region &) = delete;
1291 mapped_file_region &operator=(const mapped_file_region &) = delete;
1292
1293 /// \param fd An open file descriptor to map. Does not take ownership of fd.
1294 mapped_file_region(sys::fs::file_t fd, mapmode mode, size_t length, uint64_t offset,
1295 std::error_code &ec);
1296
1297 ~mapped_file_region() { unmapImpl(); }
1298
1299 /// Check if this is a valid mapping.
1300 explicit operator bool() const { return Mapping; }
1301
1302 /// Unmap.
1303 void unmap() {
1304 unmapImpl();
1305 copyFrom(mapped_file_region());
1306 }
1307
1308 size_t size() const;
1309 char *data() const;
1310
1311 /// Get a const view of the data. Modifying this memory has undefined
1312 /// behavior.
1313 const char *const_data() const;
1314
1315 /// \returns The minimum alignment offset must be.
1316 static int alignment();
1317};
1318
1319/// Return the path to the main executable, given the value of argv[0] from
1320/// program startup and the address of main itself. In extremis, this function
1321/// may fail and return an empty path.
1322std::string getMainExecutable(const char *argv0, void *MainExecAddr);
1323
1324/// @}
1325/// @name Iterators
1326/// @{
1327
1328/// directory_entry - A single entry in a directory.
1329class directory_entry {
1330 // FIXME: different platforms make different information available "for free"
1331 // when traversing a directory. The design of this class wraps most of the
1332 // information in basic_file_status, so on platforms where we can't populate
1333 // that whole structure, callers end up paying for a stat().
1334 // std::filesystem::directory_entry may be a better model.
1335 std::string Path;
1336 file_type Type = file_type::type_unknown; // Most platforms can provide this.
1337 bool FollowSymlinks = true; // Affects the behavior of status().
1338 basic_file_status Status; // If available.
1339
1340public:
1341 explicit directory_entry(const Twine &Path, bool FollowSymlinks = true,
1342 file_type Type = file_type::type_unknown,
1343 basic_file_status Status = basic_file_status())
1344 : Path(Path.str()), Type(Type), FollowSymlinks(FollowSymlinks),
1345 Status(Status) {}
1346
1347 directory_entry() = default;
1348
1349 void replace_filename(const Twine &Filename, file_type Type,
1350 basic_file_status Status = basic_file_status());
1351
1352 const std::string &path() const { return Path; }
1353 // Get basic information about entry file (a subset of fs::status()).
1354 // On most platforms this is a stat() call.
1355 // On windows the information was already retrieved from the directory.
1356 ErrorOr<basic_file_status> status() const;
1357 // Get the type of this file.
1358 // On most platforms (Linux/Mac/Windows/BSD), this was already retrieved.
1359 // On some platforms (e.g. Solaris) this is a stat() call.
1360 file_type type() const {
1361 if (Type != file_type::type_unknown)
1362 return Type;
1363 auto S = status();
1364 return S ? S->type() : file_type::type_unknown;
1365 }
1366
1367 bool operator==(const directory_entry& RHS) const { return Path == RHS.Path; }
1368 bool operator!=(const directory_entry& RHS) const { return !(*this == RHS); }
1369 bool operator< (const directory_entry& RHS) const;
1370 bool operator<=(const directory_entry& RHS) const;
1371 bool operator> (const directory_entry& RHS) const;
1372 bool operator>=(const directory_entry& RHS) const;
1373};
1374
1375namespace detail {
1376
1377 struct DirIterState;
1378
1379 std::error_code directory_iterator_construct(DirIterState &, StringRef, bool);
1380 std::error_code directory_iterator_increment(DirIterState &);
1381 std::error_code directory_iterator_destruct(DirIterState &);
1382
1383 /// Keeps state for the directory_iterator.
1384 struct DirIterState {
1385 ~DirIterState() {
1386 directory_iterator_destruct(*this);
1387 }
1388
1389 intptr_t IterationHandle = 0;
1390 directory_entry CurrentEntry;
1391 };
1392
1393} // end namespace detail
1394
1395/// directory_iterator - Iterates through the entries in path. There is no
1396/// operator++ because we need an error_code. If it's really needed we can make
1397/// it call report_fatal_error on error.
1398class directory_iterator {
1399 std::shared_ptr<detail::DirIterState> State;
1400 bool FollowSymlinks = true;
1401
1402public:
1403 explicit directory_iterator(const Twine &path, std::error_code &ec,
1404 bool follow_symlinks = true)
1405 : FollowSymlinks(follow_symlinks) {
1406 State = std::make_shared<detail::DirIterState>();
1407 SmallString<128> path_storage;
1408 ec = detail::directory_iterator_construct(
1409 *State, path.toStringRef(path_storage), FollowSymlinks);
1410 }
1411
1412 explicit directory_iterator(const directory_entry &de, std::error_code &ec,
1413 bool follow_symlinks = true)
1414 : FollowSymlinks(follow_symlinks) {
1415 State = std::make_shared<detail::DirIterState>();
1416 ec = detail::directory_iterator_construct(
1417 *State, de.path(), FollowSymlinks);
1418 }
1419
1420 /// Construct end iterator.
1421 directory_iterator() = default;
1422
1423 // No operator++ because we need error_code.
1424 directory_iterator &increment(std::error_code &ec) {
1425 ec = directory_iterator_increment(*State);
1426 return *this;
1427 }
1428
1429 const directory_entry &operator*() const { return State->CurrentEntry; }
1430 const directory_entry *operator->() const { return &State->CurrentEntry; }
1431
1432 bool operator==(const directory_iterator &RHS) const {
1433 if (State == RHS.State)
1434 return true;
1435 if (!RHS.State)
1436 return State->CurrentEntry == directory_entry();
1437 if (!State)
1438 return RHS.State->CurrentEntry == directory_entry();
1439 return State->CurrentEntry == RHS.State->CurrentEntry;
1440 }
1441
1442 bool operator!=(const directory_iterator &RHS) const {
1443 return !(*this == RHS);
1444 }
1445};
1446
1447namespace detail {
1448
1449 /// Keeps state for the recursive_directory_iterator.
1450 struct RecDirIterState {
1451 std::stack<directory_iterator, std::vector<directory_iterator>> Stack;
1452 uint16_t Level = 0;
1453 bool HasNoPushRequest = false;
1454 };
1455
1456} // end namespace detail
1457
1458/// recursive_directory_iterator - Same as directory_iterator except for it
1459/// recurses down into child directories.
1460class recursive_directory_iterator {
1461 std::shared_ptr<detail::RecDirIterState> State;
1462 bool Follow;
1463
1464public:
1465 recursive_directory_iterator() = default;
1466 explicit recursive_directory_iterator(const Twine &path, std::error_code &ec,
1467 bool follow_symlinks = true)
1468 : State(std::make_shared<detail::RecDirIterState>()),
1469 Follow(follow_symlinks) {
1470 State->Stack.push(directory_iterator(path, ec, Follow));
1471 if (State->Stack.top() == directory_iterator())
1472 State.reset();
1473 }
1474
1475 // No operator++ because we need error_code.
1476 recursive_directory_iterator &increment(std::error_code &ec) {
1477 const directory_iterator end_itr = {};
1478
1479 if (State->HasNoPushRequest)
1480 State->HasNoPushRequest = false;
1481 else {
1482 file_type type = State->Stack.top()->type();
1483 if (type == file_type::symlink_file && Follow) {
1484 // Resolve the symlink: is it a directory to recurse into?
1485 ErrorOr<basic_file_status> status = State->Stack.top()->status();
1486 if (status)
1487 type = status->type();
1488 // Otherwise broken symlink, and we'll continue.
1489 }
1490 if (type == file_type::directory_file) {
1491 State->Stack.push(directory_iterator(*State->Stack.top(), ec, Follow));
1492 if (State->Stack.top() != end_itr) {
1493 ++State->Level;
1494 return *this;
1495 }
1496 State->Stack.pop();
1497 }
1498 }
1499
1500 while (!State->Stack.empty()
1501 && State->Stack.top().increment(ec) == end_itr) {
1502 State->Stack.pop();
1503 --State->Level;
1504 }
1505
1506 // Check if we are done. If so, create an end iterator.
1507 if (State->Stack.empty())
1508 State.reset();
1509
1510 return *this;
1511 }
1512
1513 const directory_entry &operator*() const { return *State->Stack.top(); }
1514 const directory_entry *operator->() const { return &*State->Stack.top(); }
1515
1516 // observers
1517 /// Gets the current level. Starting path is at level 0.
1518 int level() const { return State->Level; }
1519
1520 /// Returns true if no_push has been called for this directory_entry.
1521 bool no_push_request() const { return State->HasNoPushRequest; }
1522
1523 // modifiers
1524 /// Goes up one level if Level > 0.
1525 void pop() {
1526 assert(State && "Cannot pop an end iterator!");
1527 assert(State->Level > 0 && "Cannot pop an iterator with level < 1");
1528
1529 const directory_iterator end_itr = {};
1530 std::error_code ec;
1531 do {
1532 if (ec)
1533 report_fatal_error("Error incrementing directory iterator.");
1534 State->Stack.pop();
1535 --State->Level;
1536 } while (!State->Stack.empty()
1537 && State->Stack.top().increment(ec) == end_itr);
1538
1539 // Check if we are done. If so, create an end iterator.
1540 if (State->Stack.empty())
1541 State.reset();
1542 }
1543
1544 /// Does not go down into the current directory_entry.
1545 void no_push() { State->HasNoPushRequest = true; }
1546
1547 bool operator==(const recursive_directory_iterator &RHS) const {
1548 return State == RHS.State;
1549 }
1550
1551 bool operator!=(const recursive_directory_iterator &RHS) const {
1552 return !(*this == RHS);
1553 }
1554};
1555
1556/// @}
1557
1558} // end namespace fs
1559} // end namespace sys
1560} // end namespace llvm
1561
1562#endif // LLVM_SUPPORT_FILESYSTEM_H
1563