1//===-- Path.cpp - Implement OS Path Concept ------------------------------===//
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 implements the operating system Path API.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/Support/Path.h"
14#include "llvm/ADT/ArrayRef.h"
15#include "llvm/ADT/ScopeExit.h"
16#include "llvm/ADT/StringExtras.h"
17#include "llvm/Config/config.h"
18#include "llvm/Config/llvm-config.h"
19#include "llvm/Support/Endian.h"
20#include "llvm/Support/Errc.h"
21#include "llvm/Support/ErrorHandling.h"
22#include "llvm/Support/FileSystem.h"
23#include "llvm/Support/Process.h"
24#include "llvm/Support/Signals.h"
25#include <cctype>
26
27#if !defined(_MSC_VER) && !defined(__MINGW32__)
28#include <unistd.h>
29#else
30#include <io.h>
31#endif
32
33using namespace llvm;
34using namespace llvm::support::endian;
35
36namespace {
37 using llvm::StringRef;
38 using llvm::sys::path::is_separator;
39 using llvm::sys::path::Style;
40
41 inline Style real_style(Style style) {
42 if (style != Style::native)
43 return style;
44 if (is_style_posix(S: style))
45 return Style::posix;
46 return LLVM_WINDOWS_PREFER_FORWARD_SLASH ? Style::windows_slash
47 : Style::windows_backslash;
48 }
49
50 inline const char *separators(Style style) {
51 if (is_style_windows(S: style))
52 return "\\/";
53 return "/";
54 }
55
56 inline char preferred_separator(Style style) {
57 if (real_style(style) == Style::windows)
58 return '\\';
59 return '/';
60 }
61
62 StringRef find_first_component(StringRef path, Style style) {
63 // Look for this first component in the following order.
64 // * empty (in this case we return an empty string)
65 // * either C: or {//,\\}net.
66 // * {/,\}
67 // * {file,directory}name
68
69 if (path.empty())
70 return path;
71
72 if (is_style_windows(S: style)) {
73 // C:
74 if (path.size() >= 2 &&
75 std::isalpha(static_cast<unsigned char>(path[0])) && path[1] == ':')
76 return path.substr(Start: 0, N: 2);
77 }
78
79 // //net
80 if ((path.size() > 2) && is_separator(value: path[0], style) &&
81 path[0] == path[1] && !is_separator(value: path[2], style)) {
82 // Find the next directory separator.
83 size_t end = path.find_first_of(Chars: separators(style), From: 2);
84 return path.substr(Start: 0, N: end);
85 }
86
87 // {/,\}
88 if (is_separator(value: path[0], style))
89 return path.substr(Start: 0, N: 1);
90
91 // * {file,directory}name
92 size_t end = path.find_first_of(Chars: separators(style));
93 return path.substr(Start: 0, N: end);
94 }
95
96 // Returns the first character of the filename in str. For paths ending in
97 // '/', it returns the position of the '/'.
98 size_t filename_pos(StringRef str, Style style) {
99 if (str.size() > 0 && is_separator(value: str[str.size() - 1], style))
100 return str.size() - 1;
101
102 size_t pos = str.find_last_of(Chars: separators(style), From: str.size() - 1);
103
104 if (is_style_windows(S: style)) {
105 if (pos == StringRef::npos)
106 pos = str.find_last_of(C: ':', From: str.size() - 1);
107 }
108
109 if (pos == StringRef::npos || (pos == 1 && is_separator(value: str[0], style)))
110 return 0;
111
112 return pos + 1;
113 }
114
115 // Returns the position of the root directory in str. If there is no root
116 // directory in str, it returns StringRef::npos.
117 size_t root_dir_start(StringRef str, Style style) {
118 // case "c:/"
119 if (is_style_windows(S: style)) {
120 if (str.size() > 2 && str[1] == ':' && is_separator(value: str[2], style))
121 return 2;
122 }
123
124 // case "//net"
125 if (str.size() > 3 && is_separator(value: str[0], style) && str[0] == str[1] &&
126 !is_separator(value: str[2], style)) {
127 return str.find_first_of(Chars: separators(style), From: 2);
128 }
129
130 // case "/"
131 if (str.size() > 0 && is_separator(value: str[0], style))
132 return 0;
133
134 return StringRef::npos;
135 }
136
137 // Returns the position past the end of the "parent path" of path. The parent
138 // path will not end in '/', unless the parent is the root directory. If the
139 // path has no parent, 0 is returned.
140 size_t parent_path_end(StringRef path, Style style) {
141 size_t end_pos = filename_pos(str: path, style);
142
143 bool filename_was_sep =
144 path.size() > 0 && is_separator(value: path[end_pos], style);
145
146 // Skip separators until we reach root dir (or the start of the string).
147 size_t root_dir_pos = root_dir_start(str: path, style);
148 while (end_pos > 0 &&
149 (root_dir_pos == StringRef::npos || end_pos > root_dir_pos) &&
150 is_separator(value: path[end_pos - 1], style))
151 --end_pos;
152
153 if (end_pos == root_dir_pos && !filename_was_sep) {
154 // We've reached the root dir and the input path was *not* ending in a
155 // sequence of slashes. Include the root dir in the parent path.
156 return root_dir_pos + 1;
157 }
158
159 // Otherwise, just include before the last slash.
160 return end_pos;
161 }
162} // end unnamed namespace
163
164enum FSEntity {
165 FS_Dir,
166 FS_File,
167 FS_Name
168};
169
170static std::error_code
171createUniqueEntity(const Twine &Model, int &ResultFD,
172 SmallVectorImpl<char> &ResultPath, bool MakeAbsolute,
173 FSEntity Type, sys::fs::OpenFlags Flags = sys::fs::OF_None,
174 unsigned Mode = 0) {
175
176 // Limit the number of attempts we make, so that we don't infinite loop. E.g.
177 // "permission denied" could be for a specific file (so we retry with a
178 // different name) or for the whole directory (retry would always fail).
179 // Checking which is racy, so we try a number of times, then give up.
180 std::error_code EC;
181 for (int Retries = 128; Retries > 0; --Retries) {
182 sys::fs::createUniquePath(Model, ResultPath, MakeAbsolute);
183 // Try to open + create the file.
184 switch (Type) {
185 case FS_File: {
186 EC = sys::fs::openFileForReadWrite(Name: Twine(ResultPath.begin()), ResultFD,
187 Disp: sys::fs::CD_CreateNew, Flags, Mode);
188 if (EC) {
189 // errc::permission_denied happens on Windows when we try to open a file
190 // that has been marked for deletion.
191 if (EC == errc::file_exists || EC == errc::permission_denied)
192 continue;
193 return EC;
194 }
195
196 return std::error_code();
197 }
198
199 case FS_Name: {
200 EC = sys::fs::access(Path: ResultPath.begin(), Mode: sys::fs::AccessMode::Exist);
201 if (EC == errc::no_such_file_or_directory)
202 return std::error_code();
203 if (EC)
204 return EC;
205 continue;
206 }
207
208 case FS_Dir: {
209 EC = sys::fs::create_directory(path: ResultPath.begin(), IgnoreExisting: false);
210 if (EC) {
211 if (EC == errc::file_exists)
212 continue;
213 return EC;
214 }
215 return std::error_code();
216 }
217 }
218 llvm_unreachable("Invalid Type");
219 }
220 return EC;
221}
222
223namespace llvm {
224namespace sys {
225namespace path {
226
227const_iterator begin(StringRef path, Style style) {
228 const_iterator i;
229 i.Path = path;
230 i.Component = find_first_component(path, style);
231 i.Position = 0;
232 i.S = style;
233 return i;
234}
235
236const_iterator end(StringRef path) {
237 const_iterator i;
238 i.Path = path;
239 i.Position = path.size();
240 return i;
241}
242
243const_iterator &const_iterator::operator++() {
244 assert(Position < Path.size() && "Tried to increment past end!");
245
246 // Increment Position to past the current component
247 Position += Component.size();
248
249 // Check for end.
250 if (Position == Path.size()) {
251 Component = StringRef();
252 return *this;
253 }
254
255 // Both POSIX and Windows treat paths that begin with exactly two separators
256 // specially.
257 bool was_net = Component.size() > 2 && is_separator(value: Component[0], style: S) &&
258 Component[1] == Component[0] && !is_separator(value: Component[2], style: S);
259
260 // Handle separators.
261 if (is_separator(value: Path[Position], style: S)) {
262 // Root dir.
263 if (was_net ||
264 // c:/
265 (is_style_windows(S) && Component.ends_with(Suffix: ":"))) {
266 Component = Path.substr(Start: Position, N: 1);
267 return *this;
268 }
269
270 // Skip extra separators.
271 while (Position != Path.size() && is_separator(value: Path[Position], style: S)) {
272 ++Position;
273 }
274
275 // Treat trailing '/' as a '.', unless it is the root dir.
276 if (Position == Path.size() && Component != "/") {
277 --Position;
278 Component = ".";
279 return *this;
280 }
281 }
282
283 // Find next component.
284 size_t end_pos = Path.find_first_of(Chars: separators(style: S), From: Position);
285 Component = Path.slice(Start: Position, End: end_pos);
286
287 return *this;
288}
289
290bool const_iterator::operator==(const const_iterator &RHS) const {
291 return Path.begin() == RHS.Path.begin() && Position == RHS.Position;
292}
293
294ptrdiff_t const_iterator::operator-(const const_iterator &RHS) const {
295 return Position - RHS.Position;
296}
297
298reverse_iterator rbegin(StringRef Path, Style style) {
299 reverse_iterator I;
300 I.Path = Path;
301 I.Position = Path.size();
302 I.S = style;
303 ++I;
304 return I;
305}
306
307reverse_iterator rend(StringRef Path) {
308 reverse_iterator I;
309 I.Path = Path;
310 I.Component = Path.substr(Start: 0, N: 0);
311 I.Position = 0;
312 return I;
313}
314
315reverse_iterator &reverse_iterator::operator++() {
316 size_t root_dir_pos = root_dir_start(str: Path, style: S);
317
318 // Skip separators unless it's the root directory.
319 size_t end_pos = Position;
320 while (end_pos > 0 && (end_pos - 1) != root_dir_pos &&
321 is_separator(value: Path[end_pos - 1], style: S))
322 --end_pos;
323
324 // Treat trailing '/' as a '.', unless it is the root dir.
325 if (Position == Path.size() && !Path.empty() &&
326 is_separator(value: Path.back(), style: S) &&
327 (root_dir_pos == StringRef::npos || end_pos - 1 > root_dir_pos)) {
328 --Position;
329 Component = ".";
330 return *this;
331 }
332
333 // Find next separator.
334 size_t start_pos = filename_pos(str: Path.substr(Start: 0, N: end_pos), style: S);
335 Component = Path.slice(Start: start_pos, End: end_pos);
336 Position = start_pos;
337 return *this;
338}
339
340bool reverse_iterator::operator==(const reverse_iterator &RHS) const {
341 return Path.begin() == RHS.Path.begin() && Component == RHS.Component &&
342 Position == RHS.Position;
343}
344
345ptrdiff_t reverse_iterator::operator-(const reverse_iterator &RHS) const {
346 return Position - RHS.Position;
347}
348
349StringRef root_path(StringRef path, Style style) {
350 const_iterator b = begin(path, style), pos = b, e = end(path);
351 if (b != e) {
352 bool has_net =
353 b->size() > 2 && is_separator(value: (*b)[0], style) && (*b)[1] == (*b)[0];
354 bool has_drive = is_style_windows(S: style) && b->ends_with(Suffix: ":");
355
356 if (has_net || has_drive) {
357 if ((++pos != e) && is_separator(value: (*pos)[0], style)) {
358 // {C:/,//net/}, so get the first two components.
359 return path.substr(Start: 0, N: b->size() + pos->size());
360 }
361 // just {C:,//net}, return the first component.
362 return *b;
363 }
364
365 // POSIX style root directory.
366 if (is_separator(value: (*b)[0], style)) {
367 return *b;
368 }
369 }
370
371 return StringRef();
372}
373
374StringRef root_name(StringRef path, Style style) {
375 const_iterator b = begin(path, style), e = end(path);
376 if (b != e) {
377 bool has_net =
378 b->size() > 2 && is_separator(value: (*b)[0], style) && (*b)[1] == (*b)[0];
379 bool has_drive = is_style_windows(S: style) && b->ends_with(Suffix: ":");
380
381 if (has_net || has_drive) {
382 // just {C:,//net}, return the first component.
383 return *b;
384 }
385 }
386
387 // No path or no name.
388 return StringRef();
389}
390
391StringRef root_directory(StringRef path, Style style) {
392 const_iterator b = begin(path, style), pos = b, e = end(path);
393 if (b != e) {
394 bool has_net =
395 b->size() > 2 && is_separator(value: (*b)[0], style) && (*b)[1] == (*b)[0];
396 bool has_drive = is_style_windows(S: style) && b->ends_with(Suffix: ":");
397
398 if ((has_net || has_drive) &&
399 // {C:,//net}, skip to the next component.
400 (++pos != e) && is_separator(value: (*pos)[0], style)) {
401 return *pos;
402 }
403
404 // POSIX style root directory.
405 if (!has_net && is_separator(value: (*b)[0], style)) {
406 return *b;
407 }
408 }
409
410 // No path or no root.
411 return StringRef();
412}
413
414StringRef relative_path(StringRef path, Style style) {
415 StringRef root = root_path(path, style);
416 return path.substr(Start: root.size());
417}
418
419void append(SmallVectorImpl<char> &path, Style style, const Twine &a,
420 const Twine &b, const Twine &c, const Twine &d) {
421 SmallString<32> a_storage;
422 SmallString<32> b_storage;
423 SmallString<32> c_storage;
424 SmallString<32> d_storage;
425
426 SmallVector<StringRef, 4> components;
427 if (!a.isTriviallyEmpty()) components.push_back(Elt: a.toStringRef(Out&: a_storage));
428 if (!b.isTriviallyEmpty()) components.push_back(Elt: b.toStringRef(Out&: b_storage));
429 if (!c.isTriviallyEmpty()) components.push_back(Elt: c.toStringRef(Out&: c_storage));
430 if (!d.isTriviallyEmpty()) components.push_back(Elt: d.toStringRef(Out&: d_storage));
431
432 for (auto &component : components) {
433 bool path_has_sep =
434 !path.empty() && is_separator(value: path[path.size() - 1], style);
435 if (path_has_sep) {
436 // Strip separators from beginning of component.
437 size_t loc = component.find_first_not_of(Chars: separators(style));
438 StringRef c = component.substr(Start: loc);
439
440 // Append it.
441 path.append(in_start: c.begin(), in_end: c.end());
442 continue;
443 }
444
445 bool component_has_sep =
446 !component.empty() && is_separator(value: component[0], style);
447 if (!component_has_sep &&
448 !(path.empty() || has_root_name(path: component, style))) {
449 // Add a separator.
450 path.push_back(Elt: preferred_separator(style));
451 }
452
453 path.append(in_start: component.begin(), in_end: component.end());
454 }
455}
456
457void append(SmallVectorImpl<char> &path, const Twine &a, const Twine &b,
458 const Twine &c, const Twine &d) {
459 append(path, style: Style::native, a, b, c, d);
460}
461
462void append(SmallVectorImpl<char> &path, const_iterator begin,
463 const_iterator end, Style style) {
464 for (; begin != end; ++begin)
465 path::append(path, style, a: *begin);
466}
467
468StringRef parent_path(StringRef path, Style style) {
469 size_t end_pos = parent_path_end(path, style);
470 if (end_pos == StringRef::npos)
471 return StringRef();
472 return path.substr(Start: 0, N: end_pos);
473}
474
475void remove_filename(SmallVectorImpl<char> &path, Style style) {
476 size_t end_pos = parent_path_end(path: StringRef(path.begin(), path.size()), style);
477 if (end_pos != StringRef::npos)
478 path.truncate(N: end_pos);
479}
480
481void replace_extension(SmallVectorImpl<char> &path, const Twine &extension,
482 Style style) {
483 StringRef p(path.begin(), path.size());
484 SmallString<32> ext_storage;
485 StringRef ext = extension.toStringRef(Out&: ext_storage);
486
487 // Erase existing extension.
488 size_t pos = p.find_last_of(C: '.');
489 if (pos != StringRef::npos && pos >= filename_pos(str: p, style))
490 path.truncate(N: pos);
491
492 // Append '.' if needed.
493 if (ext.size() > 0 && ext[0] != '.')
494 path.push_back(Elt: '.');
495
496 // Append extension.
497 path.append(in_start: ext.begin(), in_end: ext.end());
498}
499
500static bool starts_with(StringRef Path, StringRef Prefix,
501 Style style = Style::native) {
502 // Windows prefix matching : case and separator insensitive
503 if (is_style_windows(S: style)) {
504 if (Path.size() < Prefix.size())
505 return false;
506 for (size_t I = 0, E = Prefix.size(); I != E; ++I) {
507 bool SepPath = is_separator(value: Path[I], style);
508 bool SepPrefix = is_separator(value: Prefix[I], style);
509 if (SepPath != SepPrefix)
510 return false;
511 if (!SepPath && toLower(x: Path[I]) != toLower(x: Prefix[I]))
512 return false;
513 }
514 return true;
515 }
516 return Path.starts_with(Prefix);
517}
518
519bool replace_path_prefix(SmallVectorImpl<char> &Path, StringRef OldPrefix,
520 StringRef NewPrefix, Style style) {
521 if (OldPrefix.empty() && NewPrefix.empty())
522 return false;
523
524 StringRef OrigPath(Path.begin(), Path.size());
525 if (!starts_with(Path: OrigPath, Prefix: OldPrefix, style))
526 return false;
527
528 // If prefixes have the same size we can simply copy the new one over.
529 if (OldPrefix.size() == NewPrefix.size()) {
530 llvm::copy(Range&: NewPrefix, Out: Path.begin());
531 return true;
532 }
533
534 StringRef RelPath = OrigPath.substr(Start: OldPrefix.size());
535 SmallString<256> NewPath;
536 (Twine(NewPrefix) + RelPath).toVector(Out&: NewPath);
537 Path.swap(RHS&: NewPath);
538 return true;
539}
540
541void native(const Twine &path, SmallVectorImpl<char> &result, Style style) {
542 assert((!path.isSingleStringRef() ||
543 path.getSingleStringRef().data() != result.data()) &&
544 "path and result are not allowed to overlap!");
545 // Clear result.
546 result.clear();
547 path.toVector(Out&: result);
548 native(path&: result, style);
549}
550
551void native(SmallVectorImpl<char> &Path, Style style) {
552 if (Path.empty())
553 return;
554 if (is_style_windows(S: style)) {
555 for (char &Ch : Path)
556 if (is_separator(value: Ch, style))
557 Ch = preferred_separator(style);
558 if (Path[0] == '~' && (Path.size() == 1 || is_separator(value: Path[1], style))) {
559 SmallString<128> PathHome;
560 home_directory(result&: PathHome);
561 PathHome.append(in_start: Path.begin() + 1, in_end: Path.end());
562 Path = PathHome;
563 }
564 } else {
565 std::replace(first: Path.begin(), last: Path.end(), old_value: '\\', new_value: '/');
566 }
567}
568
569std::string convert_to_slash(StringRef path, Style style) {
570 if (is_style_posix(S: style))
571 return std::string(path);
572
573 std::string s = path.str();
574 std::replace(first: s.begin(), last: s.end(), old_value: '\\', new_value: '/');
575 return s;
576}
577
578StringRef filename(StringRef path, Style style) { return *rbegin(Path: path, style); }
579
580StringRef stem(StringRef path, Style style) {
581 StringRef fname = filename(path, style);
582 size_t pos = fname.find_last_of(C: '.');
583 if (pos == StringRef::npos)
584 return fname;
585 if ((fname.size() == 1 && fname == ".") ||
586 (fname.size() == 2 && fname == ".."))
587 return fname;
588 return fname.substr(Start: 0, N: pos);
589}
590
591StringRef extension(StringRef path, Style style) {
592 StringRef fname = filename(path, style);
593 size_t pos = fname.find_last_of(C: '.');
594 if (pos == StringRef::npos)
595 return StringRef();
596 if ((fname.size() == 1 && fname == ".") ||
597 (fname.size() == 2 && fname == ".."))
598 return StringRef();
599 return fname.substr(Start: pos);
600}
601
602bool is_separator(char value, Style style) {
603 if (value == '/')
604 return true;
605 if (is_style_windows(S: style))
606 return value == '\\';
607 return false;
608}
609
610StringRef get_separator(Style style) {
611 if (real_style(style) == Style::windows)
612 return "\\";
613 return "/";
614}
615
616bool has_root_name(const Twine &path, Style style) {
617 SmallString<128> path_storage;
618 StringRef p = path.toStringRef(Out&: path_storage);
619
620 return !root_name(path: p, style).empty();
621}
622
623bool has_root_directory(const Twine &path, Style style) {
624 SmallString<128> path_storage;
625 StringRef p = path.toStringRef(Out&: path_storage);
626
627 return !root_directory(path: p, style).empty();
628}
629
630bool has_root_path(const Twine &path, Style style) {
631 SmallString<128> path_storage;
632 StringRef p = path.toStringRef(Out&: path_storage);
633
634 return !root_path(path: p, style).empty();
635}
636
637bool has_relative_path(const Twine &path, Style style) {
638 SmallString<128> path_storage;
639 StringRef p = path.toStringRef(Out&: path_storage);
640
641 return !relative_path(path: p, style).empty();
642}
643
644bool has_filename(const Twine &path, Style style) {
645 SmallString<128> path_storage;
646 StringRef p = path.toStringRef(Out&: path_storage);
647
648 return !filename(path: p, style).empty();
649}
650
651bool has_parent_path(const Twine &path, Style style) {
652 SmallString<128> path_storage;
653 StringRef p = path.toStringRef(Out&: path_storage);
654
655 return !parent_path(path: p, style).empty();
656}
657
658bool has_stem(const Twine &path, Style style) {
659 SmallString<128> path_storage;
660 StringRef p = path.toStringRef(Out&: path_storage);
661
662 return !stem(path: p, style).empty();
663}
664
665bool has_extension(const Twine &path, Style style) {
666 SmallString<128> path_storage;
667 StringRef p = path.toStringRef(Out&: path_storage);
668
669 return !extension(path: p, style).empty();
670}
671
672bool is_absolute(const Twine &path, Style style) {
673 SmallString<128> path_storage;
674 StringRef p = path.toStringRef(Out&: path_storage);
675
676 bool rootDir = has_root_directory(path: p, style);
677 bool rootName = is_style_posix(S: style) || has_root_name(path: p, style);
678
679 return rootDir && rootName;
680}
681
682bool is_absolute_gnu(const Twine &path, Style style) {
683 SmallString<128> path_storage;
684 StringRef p = path.toStringRef(Out&: path_storage);
685
686 // Handle '/' which is absolute for both Windows and POSIX systems.
687 // Handle '\\' on Windows.
688 if (!p.empty() && is_separator(value: p.front(), style))
689 return true;
690
691 if (is_style_windows(S: style)) {
692 // Handle drive letter pattern (a character followed by ':') on Windows.
693 if (p.size() >= 2 && (p[0] && p[1] == ':'))
694 return true;
695 }
696
697 return false;
698}
699
700bool is_relative(const Twine &path, Style style) {
701 return !is_absolute(path, style);
702}
703
704StringRef remove_leading_dotslash(StringRef Path, Style style) {
705 // Remove leading "./" (or ".//" or "././" etc.)
706 while (Path.size() > 2 && Path[0] == '.' && is_separator(value: Path[1], style)) {
707 Path = Path.substr(Start: 2);
708 while (Path.size() > 0 && is_separator(value: Path[0], style))
709 Path = Path.substr(Start: 1);
710 }
711 return Path;
712}
713
714// Remove path traversal components ("." and "..") when possible, and
715// canonicalize slashes.
716bool remove_dots(SmallVectorImpl<char> &the_path, bool remove_dot_dot,
717 Style style) {
718 style = real_style(style);
719 StringRef remaining(the_path.data(), the_path.size());
720 bool needs_change = false;
721 SmallVector<StringRef, 16> components;
722
723 // Consume the root path, if present.
724 StringRef root = path::root_path(path: remaining, style);
725 bool absolute = !root.empty();
726 if (absolute)
727 remaining = remaining.drop_front(N: root.size());
728
729 // Loop over path components manually. This makes it easier to detect
730 // non-preferred slashes and double separators that must be canonicalized.
731 while (!remaining.empty()) {
732 size_t next_slash = remaining.find_first_of(Chars: separators(style));
733 if (next_slash == StringRef::npos)
734 next_slash = remaining.size();
735 StringRef component = remaining.take_front(N: next_slash);
736 remaining = remaining.drop_front(N: next_slash);
737
738 // Eat the slash, and check if it is the preferred separator.
739 if (!remaining.empty()) {
740 needs_change |= remaining.front() != preferred_separator(style);
741 remaining = remaining.drop_front();
742 // The path needs to be rewritten if it has a trailing slash.
743 // FIXME: This is emergent behavior that could be removed.
744 needs_change |= remaining.empty();
745 }
746
747 // Check for path traversal components or double separators.
748 if (component.empty() || component == ".") {
749 needs_change = true;
750 } else if (remove_dot_dot && component == "..") {
751 needs_change = true;
752 // Do not allow ".." to remove the root component. If this is the
753 // beginning of a relative path, keep the ".." component.
754 if (!components.empty() && components.back() != "..") {
755 components.pop_back();
756 } else if (!absolute) {
757 components.push_back(Elt: component);
758 }
759 } else {
760 components.push_back(Elt: component);
761 }
762 }
763
764 SmallString<256> buffer = root;
765 // "root" could be "/", which may need to be translated into "\".
766 make_preferred(path&: buffer, style);
767 needs_change |= root != buffer;
768
769 // Avoid rewriting the path unless we have to.
770 if (!needs_change)
771 return false;
772
773 if (!components.empty()) {
774 buffer += components[0];
775 for (StringRef C : ArrayRef(components).drop_front()) {
776 buffer += preferred_separator(style);
777 buffer += C;
778 }
779 }
780 the_path.swap(RHS&: buffer);
781 return true;
782}
783
784} // end namespace path
785
786namespace fs {
787
788std::error_code getUniqueID(const Twine Path, UniqueID &Result) {
789 file_status Status;
790 std::error_code EC = status(path: Path, result&: Status);
791 if (EC)
792 return EC;
793 Result = Status.getUniqueID();
794 return std::error_code();
795}
796
797void createUniquePath(const Twine &Model, SmallVectorImpl<char> &ResultPath,
798 bool MakeAbsolute) {
799 SmallString<128> ModelStorage;
800 Model.toVector(Out&: ModelStorage);
801
802 if (MakeAbsolute) {
803 // Make model absolute by prepending a temp directory if it's not already.
804 if (!sys::path::is_absolute(path: Twine(ModelStorage))) {
805 SmallString<128> TDir;
806 sys::path::system_temp_directory(erasedOnReboot: true, result&: TDir);
807 sys::path::append(path&: TDir, a: Twine(ModelStorage));
808 ModelStorage.swap(RHS&: TDir);
809 }
810 }
811
812 ResultPath = ModelStorage;
813 ResultPath.push_back(Elt: 0);
814 ResultPath.pop_back();
815
816 // Replace '%' with random chars.
817 for (unsigned i = 0, e = ModelStorage.size(); i != e; ++i) {
818 if (ModelStorage[i] == '%')
819 ResultPath[i] = "0123456789abcdef"[sys::Process::GetRandomNumber() & 15];
820 }
821}
822
823std::error_code createUniqueFile(const Twine &Model, int &ResultFd,
824 SmallVectorImpl<char> &ResultPath,
825 OpenFlags Flags, unsigned Mode) {
826 return createUniqueEntity(Model, ResultFD&: ResultFd, ResultPath, MakeAbsolute: false, Type: FS_File, Flags,
827 Mode);
828}
829
830std::error_code createUniqueFile(const Twine &Model,
831 SmallVectorImpl<char> &ResultPath,
832 unsigned Mode) {
833 int FD;
834 auto EC = createUniqueFile(Model, ResultFd&: FD, ResultPath, Flags: OF_None, Mode);
835 if (EC)
836 return EC;
837 // FD is only needed to avoid race conditions. Close it right away.
838 close(fd: FD);
839 return EC;
840}
841
842static std::error_code
843createTemporaryFile(const Twine &Model, int &ResultFD,
844 llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type,
845 sys::fs::OpenFlags Flags = sys::fs::OF_None) {
846 SmallString<128> Storage;
847 StringRef P = Model.toNullTerminatedStringRef(Out&: Storage);
848 assert(P.find_first_of(separators(Style::native)) == StringRef::npos &&
849 "Model must be a simple filename.");
850 // Use P.begin() so that createUniqueEntity doesn't need to recreate Storage.
851 return createUniqueEntity(Model: P.begin(), ResultFD, ResultPath, MakeAbsolute: true, Type, Flags,
852 Mode: all_read | all_write);
853}
854
855static std::error_code
856createTemporaryFile(const Twine &Prefix, StringRef Suffix, int &ResultFD,
857 llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type,
858 sys::fs::OpenFlags Flags = sys::fs::OF_None) {
859 const char *Middle = Suffix.empty() ? "-%%%%%%" : "-%%%%%%.";
860 return createTemporaryFile(Model: Prefix + Middle + Suffix, ResultFD, ResultPath,
861 Type, Flags);
862}
863
864std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
865 int &ResultFD,
866 SmallVectorImpl<char> &ResultPath,
867 sys::fs::OpenFlags Flags) {
868 return createTemporaryFile(Prefix, Suffix, ResultFD, ResultPath, Type: FS_File,
869 Flags);
870}
871
872std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
873 SmallVectorImpl<char> &ResultPath,
874 sys::fs::OpenFlags Flags) {
875 int FD;
876 auto EC = createTemporaryFile(Prefix, Suffix, ResultFD&: FD, ResultPath, Flags);
877 if (EC)
878 return EC;
879 // FD is only needed to avoid race conditions. Close it right away.
880 close(fd: FD);
881 return EC;
882}
883
884// This is a mkdtemp with a different pattern. We use createUniqueEntity mostly
885// for consistency. We should try using mkdtemp.
886std::error_code createUniqueDirectory(const Twine &Prefix,
887 SmallVectorImpl<char> &ResultPath) {
888 int Dummy;
889 return createUniqueEntity(Model: Prefix + "-%%%%%%", ResultFD&: Dummy, ResultPath, MakeAbsolute: true,
890 Type: FS_Dir);
891}
892
893std::error_code
894getPotentiallyUniqueFileName(const Twine &Model,
895 SmallVectorImpl<char> &ResultPath) {
896 int Dummy;
897 return createUniqueEntity(Model, ResultFD&: Dummy, ResultPath, MakeAbsolute: false, Type: FS_Name);
898}
899
900std::error_code
901getPotentiallyUniqueTempFileName(const Twine &Prefix, StringRef Suffix,
902 SmallVectorImpl<char> &ResultPath) {
903 int Dummy;
904 return createTemporaryFile(Prefix, Suffix, ResultFD&: Dummy, ResultPath, Type: FS_Name);
905}
906
907void make_absolute(const Twine &current_directory,
908 SmallVectorImpl<char> &path) {
909 StringRef p(path.data(), path.size());
910
911 bool rootDirectory = path::has_root_directory(path: p);
912 bool rootName = path::has_root_name(path: p);
913
914 // Already absolute.
915 if ((rootName || is_style_posix(S: Style::native)) && rootDirectory)
916 return;
917
918 // All of the following conditions will need the current directory.
919 SmallString<128> current_dir;
920 current_directory.toVector(Out&: current_dir);
921
922 // Relative path. Prepend the current directory.
923 if (!rootName && !rootDirectory) {
924 // Append path to the current directory.
925 path::append(path&: current_dir, a: p);
926 // Set path to the result.
927 path.swap(RHS&: current_dir);
928 return;
929 }
930
931 if (!rootName && rootDirectory) {
932 StringRef cdrn = path::root_name(path: current_dir);
933 SmallString<128> curDirRootName(cdrn.begin(), cdrn.end());
934 path::append(path&: curDirRootName, a: p);
935 // Set path to the result.
936 path.swap(RHS&: curDirRootName);
937 return;
938 }
939
940 if (rootName && !rootDirectory) {
941 StringRef pRootName = path::root_name(path: p);
942 StringRef bRootDirectory = path::root_directory(path: current_dir);
943 StringRef bRelativePath = path::relative_path(path: current_dir);
944 StringRef pRelativePath = path::relative_path(path: p);
945
946 SmallString<128> res;
947 path::append(path&: res, a: pRootName, b: bRootDirectory, c: bRelativePath, d: pRelativePath);
948 path.swap(RHS&: res);
949 return;
950 }
951
952 llvm_unreachable("All rootName and rootDirectory combinations should have "
953 "occurred above!");
954}
955
956std::error_code make_absolute(SmallVectorImpl<char> &path) {
957 if (path::is_absolute(path))
958 return {};
959
960 SmallString<128> current_dir;
961 if (std::error_code ec = current_path(result&: current_dir))
962 return ec;
963
964 make_absolute(current_directory: current_dir, path);
965 return {};
966}
967
968std::error_code create_directories(const Twine &Path, bool IgnoreExisting,
969 perms Perms) {
970 SmallString<128> PathStorage;
971 StringRef P = Path.toStringRef(Out&: PathStorage);
972
973 // Be optimistic and try to create the directory
974 std::error_code EC = create_directory(path: P, IgnoreExisting, Perms);
975 // If we succeeded, or had any error other than the parent not existing, just
976 // return it.
977 if (EC != errc::no_such_file_or_directory)
978 return EC;
979
980 // We failed because of a no_such_file_or_directory, try to create the
981 // parent.
982 StringRef Parent = path::parent_path(path: P);
983 if (Parent.empty())
984 return EC;
985
986 if ((EC = create_directories(Path: Parent, IgnoreExisting, Perms)))
987 return EC;
988
989 return create_directory(path: P, IgnoreExisting, Perms);
990}
991
992static std::error_code copy_file_internal(int ReadFD, int WriteFD) {
993 const size_t BufSize = 4096;
994 char *Buf = new char[BufSize];
995 int BytesRead = 0, BytesWritten = 0;
996 for (;;) {
997 BytesRead = read(fd: ReadFD, buf: Buf, nbytes: BufSize);
998 if (BytesRead <= 0)
999 break;
1000 while (BytesRead) {
1001 BytesWritten = write(fd: WriteFD, buf: Buf, n: BytesRead);
1002 if (BytesWritten < 0)
1003 break;
1004 BytesRead -= BytesWritten;
1005 }
1006 if (BytesWritten < 0)
1007 break;
1008 }
1009 delete[] Buf;
1010
1011 if (BytesRead < 0 || BytesWritten < 0)
1012 return errnoAsErrorCode();
1013 return std::error_code();
1014}
1015
1016#ifndef __APPLE__
1017std::error_code copy_file(const Twine &From, const Twine &To) {
1018 int ReadFD, WriteFD;
1019 if (std::error_code EC = openFileForRead(Name: From, ResultFD&: ReadFD, Flags: OF_None))
1020 return EC;
1021 if (std::error_code EC =
1022 openFileForWrite(Name: To, ResultFD&: WriteFD, Disp: CD_CreateAlways, Flags: OF_None)) {
1023 close(fd: ReadFD);
1024 return EC;
1025 }
1026
1027 std::error_code EC = copy_file_internal(ReadFD, WriteFD);
1028
1029 close(fd: ReadFD);
1030 close(fd: WriteFD);
1031
1032 return EC;
1033}
1034#endif
1035
1036std::error_code copy_file(const Twine &From, int ToFD) {
1037 int ReadFD;
1038 if (std::error_code EC = openFileForRead(Name: From, ResultFD&: ReadFD, Flags: OF_None))
1039 return EC;
1040
1041 std::error_code EC = copy_file_internal(ReadFD, WriteFD: ToFD);
1042
1043 close(fd: ReadFD);
1044
1045 return EC;
1046}
1047
1048ErrorOr<MD5::MD5Result> md5_contents(int FD) {
1049 MD5 Hash;
1050
1051 constexpr size_t BufSize = 4096;
1052 std::vector<uint8_t> Buf(BufSize);
1053 int BytesRead = 0;
1054 for (;;) {
1055 BytesRead = read(fd: FD, buf: Buf.data(), nbytes: BufSize);
1056 if (BytesRead <= 0)
1057 break;
1058 Hash.update(Data: ArrayRef(Buf.data(), BytesRead));
1059 }
1060
1061 if (BytesRead < 0)
1062 return errnoAsErrorCode();
1063 MD5::MD5Result Result;
1064 Hash.final(Result);
1065 return Result;
1066}
1067
1068ErrorOr<MD5::MD5Result> md5_contents(const Twine &Path) {
1069 int FD;
1070 if (auto EC = openFileForRead(Name: Path, ResultFD&: FD, Flags: OF_None))
1071 return EC;
1072
1073 auto Result = md5_contents(FD);
1074 close(fd: FD);
1075 return Result;
1076}
1077
1078bool exists(const basic_file_status &status) {
1079 return status_known(s: status) && status.type() != file_type::file_not_found;
1080}
1081
1082bool status_known(const basic_file_status &s) {
1083 return s.type() != file_type::status_error;
1084}
1085
1086file_type get_file_type(const Twine &Path, bool Follow) {
1087 file_status st;
1088 if (status(path: Path, result&: st, follow: Follow))
1089 return file_type::status_error;
1090 return st.type();
1091}
1092
1093bool is_directory(const basic_file_status &status) {
1094 return status.type() == file_type::directory_file;
1095}
1096
1097std::error_code is_directory(const Twine &path, bool &result) {
1098 file_status st;
1099 if (std::error_code ec = status(path, result&: st))
1100 return ec;
1101 result = is_directory(status: st);
1102 return std::error_code();
1103}
1104
1105bool is_regular_file(const basic_file_status &status) {
1106 return status.type() == file_type::regular_file;
1107}
1108
1109std::error_code is_regular_file(const Twine &path, bool &result) {
1110 file_status st;
1111 if (std::error_code ec = status(path, result&: st))
1112 return ec;
1113 result = is_regular_file(status: st);
1114 return std::error_code();
1115}
1116
1117bool is_symlink_file(const basic_file_status &status) {
1118 return status.type() == file_type::symlink_file;
1119}
1120
1121std::error_code is_symlink_file(const Twine &path, bool &result) {
1122 file_status st;
1123 if (std::error_code ec = status(path, result&: st, follow: false))
1124 return ec;
1125 result = is_symlink_file(status: st);
1126 return std::error_code();
1127}
1128
1129bool is_other(const basic_file_status &status) {
1130 return exists(status) &&
1131 !is_regular_file(status) &&
1132 !is_directory(status);
1133}
1134
1135std::error_code is_other(const Twine &Path, bool &Result) {
1136 file_status FileStatus;
1137 if (std::error_code EC = status(path: Path, result&: FileStatus))
1138 return EC;
1139 Result = is_other(status: FileStatus);
1140 return std::error_code();
1141}
1142
1143void directory_entry::replace_filename(const Twine &Filename, file_type Type,
1144 basic_file_status Status) {
1145 SmallString<128> PathStr = path::parent_path(path: Path);
1146 path::append(path&: PathStr, a: Filename);
1147 this->Path = std::string(PathStr);
1148 this->Type = Type;
1149 this->Status = Status;
1150}
1151
1152ErrorOr<perms> getPermissions(const Twine &Path) {
1153 file_status Status;
1154 if (std::error_code EC = status(path: Path, result&: Status))
1155 return EC;
1156
1157 return Status.permissions();
1158}
1159
1160size_t mapped_file_region::size() const {
1161 assert(Mapping && "Mapping failed but used anyway!");
1162 return Size;
1163}
1164
1165char *mapped_file_region::data() const {
1166 assert(Mapping && "Mapping failed but used anyway!");
1167 return reinterpret_cast<char *>(Mapping);
1168}
1169
1170const char *mapped_file_region::const_data() const {
1171 assert(Mapping && "Mapping failed but used anyway!");
1172 return reinterpret_cast<const char *>(Mapping);
1173}
1174
1175Error readNativeFileToEOF(file_t FileHandle, SmallVectorImpl<char> &Buffer,
1176 ssize_t ChunkSize) {
1177 // Install a handler to truncate the buffer to the correct size on exit.
1178 size_t Size = Buffer.size();
1179 auto TruncateOnExit = make_scope_exit(F: [&]() { Buffer.truncate(N: Size); });
1180
1181 // Read into Buffer until we hit EOF.
1182 for (;;) {
1183 Buffer.resize_for_overwrite(N: Size + ChunkSize);
1184 Expected<size_t> ReadBytes = readNativeFile(
1185 FileHandle, Buf: MutableArrayRef(Buffer.begin() + Size, ChunkSize));
1186 if (!ReadBytes)
1187 return ReadBytes.takeError();
1188 if (*ReadBytes == 0)
1189 return Error::success();
1190 Size += *ReadBytes;
1191 }
1192}
1193
1194} // end namespace fs
1195} // end namespace sys
1196} // end namespace llvm
1197
1198// Include the truly platform-specific parts.
1199#if defined(LLVM_ON_UNIX)
1200#include "Unix/Path.inc"
1201#endif
1202#if defined(_WIN32)
1203#include "Windows/Path.inc"
1204#endif
1205
1206namespace llvm {
1207namespace sys {
1208namespace fs {
1209
1210TempFile::TempFile(StringRef Name, int FD)
1211 : TmpName(std::string(Name)), FD(FD) {}
1212TempFile::TempFile(TempFile &&Other) { *this = std::move(Other); }
1213TempFile &TempFile::operator=(TempFile &&Other) {
1214 TmpName = std::move(Other.TmpName);
1215 FD = Other.FD;
1216 Other.Done = true;
1217 Other.FD = -1;
1218#ifdef _WIN32
1219 RemoveOnClose = Other.RemoveOnClose;
1220 Other.RemoveOnClose = false;
1221#endif
1222 return *this;
1223}
1224
1225TempFile::~TempFile() { assert(Done); }
1226
1227Error TempFile::discard() {
1228 Done = true;
1229 if (FD != -1 && close(fd: FD) == -1) {
1230 std::error_code EC = errnoAsErrorCode();
1231 return errorCodeToError(EC);
1232 }
1233 FD = -1;
1234
1235#ifdef _WIN32
1236 // On Windows, closing will remove the file, if we set the delete
1237 // disposition. If not, remove it manually.
1238 bool Remove = RemoveOnClose;
1239#else
1240 // Always try to remove the file.
1241 bool Remove = true;
1242#endif
1243 std::error_code RemoveEC;
1244 if (Remove && !TmpName.empty()) {
1245 RemoveEC = fs::remove(path: TmpName);
1246 sys::DontRemoveFileOnSignal(Filename: TmpName);
1247 if (!RemoveEC)
1248 TmpName = "";
1249 } else {
1250 TmpName = "";
1251 }
1252 return errorCodeToError(EC: RemoveEC);
1253}
1254
1255Error TempFile::keep(const Twine &Name) {
1256 assert(!Done);
1257 Done = true;
1258 // Always try to close and rename.
1259#ifdef _WIN32
1260 // If we can't cancel the delete don't rename.
1261 auto H = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
1262 std::error_code RenameEC =
1263 RemoveOnClose ? std::error_code() : setDeleteDisposition(H, false);
1264 bool ShouldDelete = false;
1265 if (!RenameEC) {
1266 RenameEC = rename_handle(H, Name);
1267 // If rename failed because it's cross-device, copy instead
1268 if (RenameEC ==
1269 std::error_code(ERROR_NOT_SAME_DEVICE, std::system_category())) {
1270 RenameEC = copy_file(TmpName, Name);
1271 ShouldDelete = true;
1272 }
1273 }
1274
1275 // If we can't rename or copy, discard the temporary file.
1276 if (RenameEC)
1277 ShouldDelete = true;
1278 if (ShouldDelete) {
1279 if (!RemoveOnClose)
1280 setDeleteDisposition(H, true);
1281 else
1282 remove(TmpName);
1283 }
1284#else
1285 std::error_code RenameEC = fs::rename(from: TmpName, to: Name);
1286 if (RenameEC) {
1287 // If we can't rename, try to copy to work around cross-device link issues.
1288 RenameEC = sys::fs::copy_file(From: TmpName, To: Name);
1289 // If we can't rename or copy, discard the temporary file.
1290 if (RenameEC)
1291 remove(path: TmpName);
1292 }
1293#endif
1294 sys::DontRemoveFileOnSignal(Filename: TmpName);
1295
1296 if (!RenameEC)
1297 TmpName = "";
1298
1299 if (close(fd: FD) == -1)
1300 return errorCodeToError(EC: errnoAsErrorCode());
1301 FD = -1;
1302
1303 return errorCodeToError(EC: RenameEC);
1304}
1305
1306Error TempFile::keep() {
1307 assert(!Done);
1308 Done = true;
1309
1310#ifdef _WIN32
1311 auto H = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
1312 if (std::error_code EC = setDeleteDisposition(H, false))
1313 return errorCodeToError(EC);
1314#endif
1315 sys::DontRemoveFileOnSignal(Filename: TmpName);
1316
1317 TmpName = "";
1318
1319 if (close(fd: FD) == -1)
1320 return errorCodeToError(EC: errnoAsErrorCode());
1321 FD = -1;
1322
1323 return Error::success();
1324}
1325
1326Expected<TempFile> TempFile::create(const Twine &Model, unsigned Mode,
1327 OpenFlags ExtraFlags) {
1328 int FD;
1329 SmallString<128> ResultPath;
1330 if (std::error_code EC =
1331 createUniqueFile(Model, ResultFd&: FD, ResultPath, Flags: OF_Delete | ExtraFlags, Mode))
1332 return errorCodeToError(EC);
1333
1334 TempFile Ret(ResultPath, FD);
1335#ifdef _WIN32
1336 auto H = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
1337 bool SetSignalHandler = false;
1338 if (std::error_code EC = setDeleteDisposition(H, true)) {
1339 Ret.RemoveOnClose = true;
1340 SetSignalHandler = true;
1341 }
1342#else
1343 bool SetSignalHandler = true;
1344#endif
1345 if (SetSignalHandler && sys::RemoveFileOnSignal(Filename: ResultPath)) {
1346 // Make sure we delete the file when RemoveFileOnSignal fails.
1347 consumeError(Err: Ret.discard());
1348 std::error_code EC(errc::operation_not_permitted);
1349 return errorCodeToError(EC);
1350 }
1351 return std::move(Ret);
1352}
1353} // namespace fs
1354
1355} // namespace sys
1356} // namespace llvm
1357