1// Class filesystem::path -*- C++ -*-
2
3// Copyright (C) 2014-2022 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file include/bits/fs_path.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{filesystem}
28 */
29
30#ifndef _GLIBCXX_FS_PATH_H
31#define _GLIBCXX_FS_PATH_H 1
32
33#if __cplusplus >= 201703L
34
35#include <type_traits>
36#include <locale>
37#include <iosfwd>
38#include <iomanip>
39#include <codecvt>
40#include <string_view>
41#include <system_error>
42#include <bits/stl_algobase.h>
43#include <bits/stl_pair.h>
44#include <bits/locale_conv.h>
45#include <ext/concurrence.h>
46#include <bits/shared_ptr.h>
47#include <bits/unique_ptr.h>
48
49#if __cplusplus > 201703L
50# include <compare>
51#endif
52
53#if defined(_WIN32) && !defined(__CYGWIN__)
54# define _GLIBCXX_FILESYSTEM_IS_WINDOWS 1
55#endif
56
57namespace std _GLIBCXX_VISIBILITY(default)
58{
59_GLIBCXX_BEGIN_NAMESPACE_VERSION
60
61namespace filesystem
62{
63_GLIBCXX_BEGIN_NAMESPACE_CXX11
64
65 class path;
66
67 /// @cond undocumented
68namespace __detail
69{
70 /// @addtogroup filesystem
71 /// @{
72 template<typename _CharT>
73 inline constexpr bool __is_encoded_char = false;
74 template<>
75 inline constexpr bool __is_encoded_char<char> = true;
76#ifdef _GLIBCXX_USE_CHAR8_T
77 template<>
78 inline constexpr bool __is_encoded_char<char8_t> = true;
79#endif
80#if _GLIBCXX_USE_WCHAR_T
81 template<>
82 inline constexpr bool __is_encoded_char<wchar_t> = true;
83#endif
84 template<>
85 inline constexpr bool __is_encoded_char<char16_t> = true;
86 template<>
87 inline constexpr bool __is_encoded_char<char32_t> = true;
88
89#if __cpp_concepts >= 201907L
90 template<typename _Iter>
91 using __safe_iterator_traits = std::iterator_traits<_Iter>;
92#else
93 template<typename _Iter>
94 struct __safe_iterator_traits : std::iterator_traits<_Iter>
95 { };
96
97 // Protect against ill-formed iterator_traits specializations in C++17
98 template<> struct __safe_iterator_traits<void*> { };
99 template<> struct __safe_iterator_traits<const void*> { };
100 template<> struct __safe_iterator_traits<volatile void*> { };
101 template<> struct __safe_iterator_traits<const volatile void*> { };
102#endif
103
104 template<typename _Iter_traits, typename = void>
105 struct __is_path_iter_src
106 : false_type
107 { };
108
109 template<typename _Iter_traits>
110 struct __is_path_iter_src<_Iter_traits,
111 void_t<typename _Iter_traits::value_type>>
112 : bool_constant<__is_encoded_char<typename _Iter_traits::value_type>>
113 { };
114
115 template<typename _Source>
116 inline constexpr bool __is_path_src
117 = __is_path_iter_src<iterator_traits<decay_t<_Source>>>::value;
118
119 template<>
120 inline constexpr bool __is_path_src<path> = false;
121
122 template<>
123 inline constexpr bool __is_path_src<volatile path> = false;
124
125 template<>
126 inline constexpr bool __is_path_src<void*> = false;
127
128 template<>
129 inline constexpr bool __is_path_src<const void*> = false;
130
131 template<>
132 inline constexpr bool __is_path_src<volatile void*> = false;
133
134 template<>
135 inline constexpr bool __is_path_src<const volatile void*> = false;
136
137 template<typename _CharT, typename _Traits, typename _Alloc>
138 inline constexpr bool
139 __is_path_src<basic_string<_CharT, _Traits, _Alloc>>
140 = __is_encoded_char<_CharT>;
141
142 template<typename _CharT, typename _Traits>
143 inline constexpr bool
144 __is_path_src<basic_string_view<_CharT, _Traits>>
145 = __is_encoded_char<_CharT>;
146
147 // SFINAE constraint for Source parameters as required by [fs.path.req].
148 template<typename _Tp>
149 using _Path = enable_if_t<__is_path_src<_Tp>, path>;
150
151 // SFINAE constraint for InputIterator parameters as required by [fs.req].
152 template<typename _Iter, typename _Tr = __safe_iterator_traits<_Iter>>
153 using _Path2 = enable_if_t<__is_path_iter_src<_Tr>::value, path>;
154
155#if __cpp_lib_concepts
156 template<typename _Iter>
157 constexpr bool __is_contiguous = std::contiguous_iterator<_Iter>;
158#else
159 template<typename _Iter>
160 constexpr bool __is_contiguous = false;
161#endif
162
163 template<typename _Tp>
164 constexpr bool __is_contiguous<_Tp*> = true;
165
166 template<typename _Tp, typename _Seq>
167 constexpr bool
168 __is_contiguous<__gnu_cxx::__normal_iterator<_Tp*, _Seq>> = true;
169
170#if !defined _GLIBCXX_FILESYSTEM_IS_WINDOWS && defined _GLIBCXX_USE_CHAR8_T
171 // For POSIX treat char8_t sequences as char without encoding conversions.
172 template<typename _EcharT>
173 using __unified_u8_t
174 = __conditional_t<is_same_v<_EcharT, char8_t>, char, _EcharT>;
175#else
176 template<typename _EcharT>
177 using __unified_u8_t = _EcharT;
178#endif
179
180 // The __effective_range overloads convert a Source parameter into
181 // either a basic_string_view<C> or basic_string<C> containing the
182 // effective range of the Source, as defined in [fs.path.req].
183
184 template<typename _CharT, typename _Traits, typename _Alloc>
185 inline basic_string_view<_CharT>
186 __effective_range(const basic_string<_CharT, _Traits, _Alloc>& __source)
187 noexcept
188 { return __source; }
189
190 template<typename _CharT, typename _Traits>
191 inline basic_string_view<_CharT>
192 __effective_range(const basic_string_view<_CharT, _Traits>& __source)
193 noexcept
194 { return __source; }
195
196 // Return the effective range of an NTCTS.
197 template<typename _Source>
198 auto
199 __effective_range(const _Source& __source)
200 {
201 // Remove a level of normal/safe iterator indirection, or decay an array.
202 using _Iter = decltype(std::__niter_base(__source));
203 using value_type = typename iterator_traits<_Iter>::value_type;
204
205 if constexpr (__is_contiguous<_Iter>)
206 return basic_string_view<value_type>{&*__source};
207 else
208 {
209 // _Source is an input iterator that iterates over an NTCTS.
210 // Create a basic_string by reading until the null character.
211 basic_string<__unified_u8_t<value_type>> __str;
212 _Source __it = __source;
213 for (value_type __ch = *__it; __ch != value_type(); __ch = *++__it)
214 __str.push_back(__ch);
215 return __str;
216 }
217 }
218
219 // The value type of a Source parameter's effective range.
220 template<typename _Source>
221 struct __source_value_type_impl
222 {
223 using type
224 = typename __safe_iterator_traits<decay_t<_Source>>::value_type;
225 };
226
227 template<typename _CharT, typename _Traits, typename _Alloc>
228 struct __source_value_type_impl<basic_string<_CharT, _Traits, _Alloc>>
229 {
230 using type = _CharT;
231 };
232
233 template<typename _CharT, typename _Traits>
234 struct __source_value_type_impl<basic_string_view<_CharT, _Traits>>
235 {
236 using type = _CharT;
237 };
238
239 // The value type of a Source parameter's effective range.
240 template<typename _Source>
241 using __source_value_t = typename __source_value_type_impl<_Source>::type;
242
243 // SFINAE helper to check that an effective range has value_type char,
244 // as required by path constructors taking a std::locale parameter.
245 // The type _Tp must have already been checked by _Path<Tp> or _Path2<_Tp>.
246 template<typename _Tp, typename _Val = __source_value_t<_Tp>>
247 using __value_type_is_char
248 = std::enable_if_t<std::is_same_v<_Val, char>, _Val>;
249
250 // As above, but also allows char8_t, as required by u8path
251 // C++20 [depr.fs.path.factory]
252 template<typename _Tp, typename _Val = __source_value_t<_Tp>>
253 using __value_type_is_char_or_char8_t
254 = std::enable_if_t<std::is_same_v<_Val, char>
255#ifdef _GLIBCXX_USE_CHAR8_T
256 || std::is_same_v<_Val, char8_t>
257#endif
258 , _Val>;
259
260 // Create a basic_string<C> or basic_string_view<C> from an iterator range.
261 template<typename _InputIterator>
262 inline auto
263 __string_from_range(_InputIterator __first, _InputIterator __last)
264 {
265 using _EcharT
266 = typename std::iterator_traits<_InputIterator>::value_type;
267 static_assert(__is_encoded_char<_EcharT>); // C++17 [fs.req]/3
268
269 if constexpr (__is_contiguous<_InputIterator>)
270 {
271 // For contiguous iterators we can just return a string view.
272 if (auto __len = __last - __first) [[__likely__]]
273 return basic_string_view<_EcharT>(&*__first, __len);
274 return basic_string_view<_EcharT>();
275 }
276 else
277 {
278 // Conversion requires contiguous characters, so create a string.
279 return basic_string<__unified_u8_t<_EcharT>>(__first, __last);
280 }
281 }
282
283 /// @} group filesystem
284} // namespace __detail
285 /// @endcond
286
287 /// @addtogroup filesystem
288 /// @{
289
290 /// A filesystem path
291 /// @ingroup filesystem
292 class path
293 {
294 public:
295#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
296 using value_type = wchar_t;
297 static constexpr value_type preferred_separator = L'\\';
298#else
299# ifdef _GLIBCXX_DOXYGEN
300 /// Windows uses wchar_t for path::value_type, POSIX uses char.
301 using value_type = __os_dependent__;
302# else
303 using value_type = char;
304# endif
305 static constexpr value_type preferred_separator = '/';
306#endif
307 using string_type = std::basic_string<value_type>;
308
309 /// path::format is ignored in this implementation
310 enum format : unsigned char { native_format, generic_format, auto_format };
311
312 // constructors and destructor
313
314 path() noexcept { }
315
316 path(const path& __p) = default;
317
318 path(path&& __p) noexcept
319 : _M_pathname(std::move(__p._M_pathname)),
320 _M_cmpts(std::move(__p._M_cmpts))
321 { __p.clear(); }
322
323 path(string_type&& __source, format = auto_format)
324 : _M_pathname(std::move(__source))
325 { _M_split_cmpts(); }
326
327 template<typename _Source,
328 typename _Require = __detail::_Path<_Source>>
329 path(_Source const& __source, format = auto_format)
330 : _M_pathname(_S_convert(__detail::__effective_range(__source)))
331 { _M_split_cmpts(); }
332
333 template<typename _InputIterator,
334 typename _Require = __detail::_Path2<_InputIterator>>
335 path(_InputIterator __first, _InputIterator __last, format = auto_format)
336 : _M_pathname(_S_convert(__detail::__string_from_range(__first, __last)))
337 { _M_split_cmpts(); }
338
339 template<typename _Source,
340 typename _Require = __detail::_Path<_Source>,
341 typename _Require2 = __detail::__value_type_is_char<_Source>>
342 path(_Source const& __src, const locale& __loc, format = auto_format)
343 : _M_pathname(_S_convert_loc(__detail::__effective_range(__src), __loc))
344 { _M_split_cmpts(); }
345
346 template<typename _InputIterator,
347 typename _Require = __detail::_Path2<_InputIterator>,
348 typename _Req2 = __detail::__value_type_is_char<_InputIterator>>
349 path(_InputIterator __first, _InputIterator __last, const locale& __loc,
350 format = auto_format)
351 : _M_pathname(_S_convert_loc(__first, __last, __loc))
352 { _M_split_cmpts(); }
353
354 ~path() = default;
355
356 // assignments
357
358 path& operator=(const path&);
359 path& operator=(path&&) noexcept;
360 path& operator=(string_type&& __source);
361 path& assign(string_type&& __source);
362
363 template<typename _Source>
364 __detail::_Path<_Source>&
365 operator=(_Source const& __source)
366 { return *this = path(__source); }
367
368 template<typename _Source>
369 __detail::_Path<_Source>&
370 assign(_Source const& __source)
371 { return *this = path(__source); }
372
373 template<typename _InputIterator>
374 __detail::_Path2<_InputIterator>&
375 assign(_InputIterator __first, _InputIterator __last)
376 { return *this = path(__first, __last); }
377
378 // appends
379
380 path& operator/=(const path& __p);
381
382 template<typename _Source>
383 __detail::_Path<_Source>&
384 operator/=(_Source const& __source)
385 {
386 _M_append(_S_convert(__detail::__effective_range(__source)));
387 return *this;
388 }
389
390 template<typename _Source>
391 __detail::_Path<_Source>&
392 append(_Source const& __source)
393 {
394 _M_append(_S_convert(__detail::__effective_range(__source)));
395 return *this;
396 }
397
398 template<typename _InputIterator>
399 __detail::_Path2<_InputIterator>&
400 append(_InputIterator __first, _InputIterator __last)
401 {
402 _M_append(_S_convert(__detail::__string_from_range(__first, __last)));
403 return *this;
404 }
405
406 // concatenation
407
408 path& operator+=(const path& __x);
409 path& operator+=(const string_type& __x);
410 path& operator+=(const value_type* __x);
411 path& operator+=(value_type __x);
412 path& operator+=(basic_string_view<value_type> __x);
413
414 template<typename _Source>
415 __detail::_Path<_Source>&
416 operator+=(_Source const& __x) { return concat(__x); }
417
418 template<typename _CharT>
419 __detail::_Path2<_CharT*>&
420 operator+=(_CharT __x);
421
422 template<typename _Source>
423 __detail::_Path<_Source>&
424 concat(_Source const& __x)
425 {
426 _M_concat(_S_convert(__detail::__effective_range(__x)));
427 return *this;
428 }
429
430 template<typename _InputIterator>
431 __detail::_Path2<_InputIterator>&
432 concat(_InputIterator __first, _InputIterator __last)
433 {
434 _M_concat(_S_convert(__detail::__string_from_range(__first, __last)));
435 return *this;
436 }
437
438 // modifiers
439
440 void clear() noexcept { _M_pathname.clear(); _M_split_cmpts(); }
441
442 path& make_preferred();
443 path& remove_filename();
444 path& replace_filename(const path& __replacement);
445 path& replace_extension(const path& __replacement = path());
446
447 void swap(path& __rhs) noexcept;
448
449 // native format observers
450
451 const string_type& native() const noexcept { return _M_pathname; }
452 const value_type* c_str() const noexcept { return _M_pathname.c_str(); }
453 operator string_type() const { return _M_pathname; }
454
455 template<typename _CharT, typename _Traits = std::char_traits<_CharT>,
456 typename _Allocator = std::allocator<_CharT>>
457 std::basic_string<_CharT, _Traits, _Allocator>
458 string(const _Allocator& __a = _Allocator()) const;
459
460 std::string string() const;
461#if _GLIBCXX_USE_WCHAR_T
462 std::wstring wstring() const;
463#endif
464#ifdef _GLIBCXX_USE_CHAR8_T
465 __attribute__((__abi_tag__("__u8")))
466 std::u8string u8string() const;
467#else
468 std::string u8string() const;
469#endif // _GLIBCXX_USE_CHAR8_T
470 std::u16string u16string() const;
471 std::u32string u32string() const;
472
473 // generic format observers
474 template<typename _CharT, typename _Traits = std::char_traits<_CharT>,
475 typename _Allocator = std::allocator<_CharT>>
476 std::basic_string<_CharT, _Traits, _Allocator>
477 generic_string(const _Allocator& __a = _Allocator()) const;
478
479 std::string generic_string() const;
480#if _GLIBCXX_USE_WCHAR_T
481 std::wstring generic_wstring() const;
482#endif
483#ifdef _GLIBCXX_USE_CHAR8_T
484 __attribute__((__abi_tag__("__u8")))
485 std::u8string generic_u8string() const;
486#else
487 std::string generic_u8string() const;
488#endif // _GLIBCXX_USE_CHAR8_T
489 std::u16string generic_u16string() const;
490 std::u32string generic_u32string() const;
491
492 // compare
493
494 int compare(const path& __p) const noexcept;
495 int compare(const string_type& __s) const noexcept;
496 int compare(const value_type* __s) const noexcept;
497 int compare(basic_string_view<value_type> __s) const noexcept;
498
499 // decomposition
500
501 path root_name() const;
502 path root_directory() const;
503 path root_path() const;
504 path relative_path() const;
505 path parent_path() const;
506 path filename() const;
507 path stem() const;
508 path extension() const;
509
510 // query
511
512 [[nodiscard]] bool empty() const noexcept { return _M_pathname.empty(); }
513 bool has_root_name() const noexcept;
514 bool has_root_directory() const noexcept;
515 bool has_root_path() const noexcept;
516 bool has_relative_path() const noexcept;
517 bool has_parent_path() const noexcept;
518 bool has_filename() const noexcept;
519 bool has_stem() const noexcept;
520 bool has_extension() const noexcept;
521 bool is_absolute() const noexcept;
522 bool is_relative() const noexcept { return !is_absolute(); }
523
524 // generation
525 path lexically_normal() const;
526 path lexically_relative(const path& base) const;
527 path lexically_proximate(const path& base) const;
528
529 // iterators
530 class iterator;
531 using const_iterator = iterator;
532
533 iterator begin() const noexcept;
534 iterator end() const noexcept;
535
536 /// Write a path to a stream
537 template<typename _CharT, typename _Traits>
538 friend std::basic_ostream<_CharT, _Traits>&
539 operator<<(std::basic_ostream<_CharT, _Traits>& __os, const path& __p)
540 {
541 __os << std::quoted(__p.string<_CharT, _Traits>());
542 return __os;
543 }
544
545 /// Read a path from a stream
546 template<typename _CharT, typename _Traits>
547 friend std::basic_istream<_CharT, _Traits>&
548 operator>>(std::basic_istream<_CharT, _Traits>& __is, path& __p)
549 {
550 std::basic_string<_CharT, _Traits> __tmp;
551 if (__is >> std::quoted(__tmp))
552 __p = std::move(__tmp);
553 return __is;
554 }
555
556 // non-member operators
557
558 /// Compare paths
559 friend bool operator==(const path& __lhs, const path& __rhs) noexcept
560 { return path::_S_compare(__lhs, __rhs) == 0; }
561
562#if __cpp_lib_three_way_comparison
563 /// Compare paths
564 friend strong_ordering
565 operator<=>(const path& __lhs, const path& __rhs) noexcept
566 { return path::_S_compare(__lhs, __rhs) <=> 0; }
567#else
568 /// Compare paths
569 friend bool operator!=(const path& __lhs, const path& __rhs) noexcept
570 { return !(__lhs == __rhs); }
571
572 /// Compare paths
573 friend bool operator<(const path& __lhs, const path& __rhs) noexcept
574 { return __lhs.compare(p: __rhs) < 0; }
575
576 /// Compare paths
577 friend bool operator<=(const path& __lhs, const path& __rhs) noexcept
578 { return !(__rhs < __lhs); }
579
580 /// Compare paths
581 friend bool operator>(const path& __lhs, const path& __rhs) noexcept
582 { return __rhs < __lhs; }
583
584 /// Compare paths
585 friend bool operator>=(const path& __lhs, const path& __rhs) noexcept
586 { return !(__lhs < __rhs); }
587#endif
588
589 /// Append one path to another
590 friend path operator/(const path& __lhs, const path& __rhs)
591 {
592 path __result(__lhs);
593 __result /= __rhs;
594 return __result;
595 }
596
597 private:
598 enum class _Type : unsigned char {
599 _Multi = 0, _Root_name, _Root_dir, _Filename
600 };
601
602 path(basic_string_view<value_type> __str, _Type __type);
603
604 enum class _Split { _Stem, _Extension };
605
606 void _M_append(basic_string_view<value_type>);
607 void _M_concat(basic_string_view<value_type>);
608
609 pair<const string_type*, size_t> _M_find_extension() const noexcept;
610
611 // path::_S_convert creates a basic_string<value_type> or
612 // basic_string_view<value_type> from a basic_string<C> or
613 // basic_string_view<C>, for an encoded character type C,
614 // performing the conversions required by [fs.path.type.cvt].
615 template<typename _Tp>
616 static auto
617 _S_convert(_Tp __str)
618 noexcept(is_same_v<typename _Tp::value_type, value_type>)
619 {
620 if constexpr (is_same_v<typename _Tp::value_type, value_type>)
621 return __str; // No conversion needed.
622#if !defined _GLIBCXX_FILESYSTEM_IS_WINDOWS && defined _GLIBCXX_USE_CHAR8_T
623 else if constexpr (is_same_v<_Tp, std::u8string>)
624 // Calling _S_convert<char8_t> will return a u8string_view that
625 // refers to __str and would dangle after this function returns.
626 // Return a string_type instead, to avoid dangling.
627 return string_type(_S_convert(__str.data(),
628 __str.data() + __str.size()));
629#endif
630 else
631 return _S_convert(__str.data(), __str.data() + __str.size());
632 }
633
634 template<typename _EcharT>
635 static auto
636 _S_convert(const _EcharT* __first, const _EcharT* __last);
637
638 // _S_convert_loc converts a range of char to string_type, using the
639 // supplied locale for encoding conversions.
640
641 static string_type
642 _S_convert_loc(const char* __first, const char* __last,
643 const std::locale& __loc);
644
645 template<typename _Iter>
646 static string_type
647 _S_convert_loc(_Iter __first, _Iter __last, const std::locale& __loc)
648 {
649 const auto __s = __detail::__string_from_range(__first, __last);
650 return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
651 }
652
653 template<typename _Tp>
654 static string_type
655 _S_convert_loc(const _Tp& __s, const std::locale& __loc)
656 {
657 return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
658 }
659
660 template<typename _CharT, typename _Traits, typename _Allocator>
661 static basic_string<_CharT, _Traits, _Allocator>
662 _S_str_convert(basic_string_view<value_type>, const _Allocator&);
663
664 // Returns lhs.compare(rhs), but defined after path::iterator is complete.
665 __attribute__((__always_inline__))
666 static int
667 _S_compare(const path& __lhs, const path& __rhs) noexcept;
668
669 void _M_split_cmpts();
670
671 _Type _M_type() const noexcept { return _M_cmpts.type(); }
672
673 string_type _M_pathname;
674
675 struct _Cmpt;
676
677 struct _List
678 {
679 using value_type = _Cmpt;
680 using iterator = value_type*;
681 using const_iterator = const value_type*;
682
683 _List();
684 _List(const _List&);
685 _List(_List&&) = default;
686 _List& operator=(const _List&);
687 _List& operator=(_List&&) = default;
688 ~_List() = default;
689
690 _Type type() const noexcept
691 { return _Type(reinterpret_cast<uintptr_t>(_M_impl.get()) & 0x3); }
692
693 void type(_Type) noexcept;
694
695 int size() const noexcept; // zero unless type() == _Type::_Multi
696 bool empty() const noexcept; // true unless type() == _Type::_Multi
697 void clear();
698 void swap(_List& __l) noexcept { _M_impl.swap(u&: __l._M_impl); }
699 int capacity() const noexcept;
700 void reserve(int, bool); ///< @pre type() == _Type::_Multi
701
702 // All the member functions below here have a precondition !empty()
703 // (and they should only be called from within the library).
704
705 iterator begin() noexcept;
706 iterator end() noexcept;
707 const_iterator begin() const noexcept;
708 const_iterator end() const noexcept;
709
710 value_type& front() noexcept;
711 value_type& back() noexcept;
712 const value_type& front() const noexcept;
713 const value_type& back() const noexcept;
714
715 void pop_back();
716 void _M_erase_from(const_iterator __pos); // erases [__pos,end())
717
718 struct _Impl;
719 struct _Impl_deleter
720 {
721 void operator()(_Impl*) const noexcept;
722 };
723 unique_ptr<_Impl, _Impl_deleter> _M_impl;
724 };
725 _List _M_cmpts;
726
727 struct _Parser;
728
729 template<typename _EcharT> struct _Codecvt;
730 };
731
732 /// @{
733 /// @relates std::filesystem::path
734
735#if __cpp_concepts >= 201907L
736 // Workaround for PR libstdc++/106201
737 inline void
738 swap(same_as<path> auto& __lhs, same_as<path> auto& __rhs) noexcept
739 { __lhs.swap(__rhs); }
740#else
741 inline void swap(path& __lhs, path& __rhs) noexcept { __lhs.swap(__rhs); }
742#endif
743
744 size_t hash_value(const path& __p) noexcept;
745
746 /// @}
747
748 /// Exception type thrown by the Filesystem library
749 class filesystem_error : public std::system_error
750 {
751 public:
752 filesystem_error(const string& __what_arg, error_code __ec);
753
754 filesystem_error(const string& __what_arg, const path& __p1,
755 error_code __ec);
756
757 filesystem_error(const string& __what_arg, const path& __p1,
758 const path& __p2, error_code __ec);
759
760 filesystem_error(const filesystem_error&) = default;
761 filesystem_error& operator=(const filesystem_error&) = default;
762
763 // No move constructor or assignment operator.
764 // Copy rvalues instead, so that _M_impl is not left empty.
765
766 ~filesystem_error();
767
768 const path& path1() const noexcept;
769 const path& path2() const noexcept;
770 const char* what() const noexcept;
771
772 private:
773 struct _Impl;
774 std::__shared_ptr<const _Impl> _M_impl;
775 };
776
777 /// @cond undocumented
778namespace __detail
779{
780 [[noreturn]] inline void
781 __throw_conversion_error()
782 {
783 _GLIBCXX_THROW_OR_ABORT(filesystem_error(
784 "Cannot convert character sequence",
785 std::make_error_code(errc::illegal_byte_sequence)));
786 }
787
788#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
789 template<typename _Tp>
790 inline std::wstring
791 __wstr_from_utf8(const _Tp& __str)
792 {
793 static_assert(std::is_same_v<typename _Tp::value_type, char>);
794 std::wstring __wstr;
795 // XXX This assumes native wide encoding is UTF-16.
796 std::codecvt_utf8_utf16<wchar_t> __wcvt;
797 const auto __p = __str.data();
798 if (!__str_codecvt_in_all(__p, __p + __str.size(), __wstr, __wcvt))
799 __detail::__throw_conversion_error();
800 return __wstr;
801 }
802#endif
803
804} // namespace __detail
805 /// @endcond
806
807
808 /** Create a path from a UTF-8-encoded sequence of char
809 *
810 * @relates std::filesystem::path
811 */
812 template<typename _InputIterator,
813 typename _Require = __detail::_Path2<_InputIterator>,
814 typename _CharT
815 = __detail::__value_type_is_char_or_char8_t<_InputIterator>>
816 inline path
817 u8path(_InputIterator __first, _InputIterator __last)
818 {
819#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
820 if constexpr (is_same_v<_CharT, char>)
821 return path{ __detail::__wstr_from_utf8(
822 __detail::__string_from_range(__first, __last)) };
823 else
824 return path{ __first, __last }; // constructor handles char8_t
825#else
826 // This assumes native normal encoding is UTF-8.
827 return path{ __first, __last };
828#endif
829 }
830
831 /** Create a path from a UTF-8-encoded sequence of char
832 *
833 * @relates std::filesystem::path
834 */
835 template<typename _Source,
836 typename _Require = __detail::_Path<_Source>,
837 typename _CharT = __detail::__value_type_is_char_or_char8_t<_Source>>
838 inline path
839 u8path(const _Source& __source)
840 {
841#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
842 if constexpr (is_same_v<_CharT, char>)
843 return path{ __detail::__wstr_from_utf8(
844 __detail::__effective_range(__source)) };
845 else
846 return path{ __source }; // constructor handles char8_t
847#else
848 // This assumes native normal encoding is UTF-8.
849 return path{ __source };
850#endif
851 }
852
853 /// @cond undocumented
854
855 struct path::_Cmpt : path
856 {
857 _Cmpt(basic_string_view<value_type> __s, _Type __t, size_t __pos);
858
859 _Cmpt() : _M_pos(-1) { }
860
861 size_t _M_pos;
862 };
863
864 // path::_Codecvt<C> Performs conversions between C and path::string_type.
865 // The native encoding of char strings is the OS-dependent current
866 // encoding for pathnames. FIXME: We assume this is UTF-8 everywhere,
867 // but should use a Windows API to query it.
868
869 // Converts between native pathname encoding and char16_t or char32_t.
870 template<typename _EcharT>
871 struct path::_Codecvt
872 // Need derived class here because std::codecvt has protected destructor.
873 : std::codecvt<_EcharT, char, mbstate_t>
874 { };
875
876 // Converts between native pathname encoding and native wide encoding.
877 // The native encoding for wide strings is the execution wide-character
878 // set encoding. FIXME: We assume that this is either UTF-32 or UTF-16
879 // (depending on the width of wchar_t). That matches GCC's default,
880 // but can be changed with -fwide-exec-charset.
881 // We need a custom codecvt converting the native pathname encoding
882 // to/from the native wide encoding.
883 template<>
884 struct path::_Codecvt<wchar_t>
885 : __conditional_t<sizeof(wchar_t) == sizeof(char32_t),
886 std::codecvt_utf8<wchar_t>, // UTF-8 <-> UTF-32
887 std::codecvt_utf8_utf16<wchar_t>> // UTF-8 <-> UTF-16
888 { };
889
890 template<typename _EcharT>
891 auto
892 path::_S_convert(const _EcharT* __f, const _EcharT* __l)
893 {
894 static_assert(__detail::__is_encoded_char<_EcharT>);
895
896#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
897# define _GLIBCXX_CONV_FROM_UTF8(S) __detail::__wstr_from_utf8(S)
898#else
899# define _GLIBCXX_CONV_FROM_UTF8(S) S
900#endif
901
902 if constexpr (is_same_v<_EcharT, value_type>)
903 return basic_string_view<value_type>(__f, __l - __f);
904#ifdef _GLIBCXX_USE_CHAR8_T
905 else if constexpr (is_same_v<_EcharT, char8_t>)
906 {
907 string_view __str(reinterpret_cast<const char*>(__f), __l - __f);
908 return _GLIBCXX_CONV_FROM_UTF8(__str);
909 }
910#endif
911#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
912 else if constexpr (is_same_v<_EcharT, char>)
913 {
914 std::wstring __wstr;
915 path::_Codecvt<wchar_t> __cvt;
916 if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
917 return __wstr;
918 }
919#endif
920 else
921 {
922 path::_Codecvt<_EcharT> __cvt;
923 std::string __str;
924 if (__str_codecvt_out_all(__f, __l, __str, __cvt))
925 return _GLIBCXX_CONV_FROM_UTF8(__str);
926 }
927 __detail::__throw_conversion_error();
928 }
929#undef _GLIBCXX_CONV_FROM_UTF8
930
931 /// @endcond
932
933 /// An iterator for the components of a path
934 class path::iterator
935 {
936 public:
937 using difference_type = std::ptrdiff_t;
938 using value_type = path;
939 using reference = const path&;
940 using pointer = const path*;
941 using iterator_category = std::bidirectional_iterator_tag;
942
943 iterator() noexcept : _M_path(nullptr), _M_cur(), _M_at_end() { }
944
945 iterator(const iterator&) = default;
946 iterator& operator=(const iterator&) = default;
947
948 reference operator*() const noexcept;
949 pointer operator->() const noexcept { return std::__addressof(r: **this); }
950
951 iterator& operator++() noexcept;
952
953 iterator operator++(int) noexcept
954 { auto __tmp = *this; ++*this; return __tmp; }
955
956 iterator& operator--() noexcept;
957
958 iterator operator--(int) noexcept
959 { auto __tmp = *this; --*this; return __tmp; }
960
961 friend bool
962 operator==(const iterator& __lhs, const iterator& __rhs) noexcept
963 { return __lhs._M_equals(__rhs); }
964
965 friend bool
966 operator!=(const iterator& __lhs, const iterator& __rhs) noexcept
967 { return !__lhs._M_equals(__rhs); }
968
969 private:
970 friend class path;
971
972 bool
973 _M_is_multi() const noexcept
974 { return _M_path->_M_type() == _Type::_Multi; }
975
976 friend difference_type
977 __path_iter_distance(const iterator& __first, const iterator& __last)
978 noexcept
979 {
980 __glibcxx_assert(__first._M_path != nullptr);
981 __glibcxx_assert(__first._M_path == __last._M_path);
982 if (__first._M_is_multi())
983 return std::distance(first: __first._M_cur, last: __last._M_cur);
984 else if (__first._M_at_end == __last._M_at_end)
985 return 0;
986 else
987 return __first._M_at_end ? -1 : 1;
988 }
989
990 friend void
991 __path_iter_advance(iterator& __i, difference_type __n) noexcept
992 {
993 if (__n == 1)
994 ++__i;
995 else if (__n == -1)
996 --__i;
997 else if (__n != 0)
998 {
999 __glibcxx_assert(__i._M_path != nullptr);
1000 __glibcxx_assert(__i._M_is_multi());
1001 // __glibcxx_assert(__i._M_path->_M_cmpts.end() - __i._M_cur >= __n);
1002 __i._M_cur += __n;
1003 }
1004 }
1005
1006 iterator(const path* __path, path::_List::const_iterator __iter) noexcept
1007 : _M_path(__path), _M_cur(__iter), _M_at_end()
1008 { }
1009
1010 iterator(const path* __path, bool __at_end) noexcept
1011 : _M_path(__path), _M_cur(), _M_at_end(__at_end)
1012 { }
1013
1014 bool _M_equals(iterator) const noexcept;
1015
1016 const path* _M_path;
1017 path::_List::const_iterator _M_cur;
1018 bool _M_at_end; // only used when type != _Multi
1019 };
1020
1021
1022 inline path&
1023 path::operator=(path&& __p) noexcept
1024 {
1025 if (&__p == this) [[__unlikely__]]
1026 return *this;
1027
1028 _M_pathname = std::move(__p._M_pathname);
1029 _M_cmpts = std::move(__p._M_cmpts);
1030 __p.clear();
1031 return *this;
1032 }
1033
1034 inline path&
1035 path::operator=(string_type&& __source)
1036 { return *this = path(std::move(__source)); }
1037
1038 inline path&
1039 path::assign(string_type&& __source)
1040 { return *this = path(std::move(__source)); }
1041
1042 inline path&
1043 path::operator+=(const string_type& __x)
1044 {
1045 _M_concat(__x);
1046 return *this;
1047 }
1048
1049 inline path&
1050 path::operator+=(const value_type* __x)
1051 {
1052 _M_concat(__x);
1053 return *this;
1054 }
1055
1056 inline path&
1057 path::operator+=(value_type __x)
1058 {
1059 _M_concat(basic_string_view<value_type>(&__x, 1));
1060 return *this;
1061 }
1062
1063 inline path&
1064 path::operator+=(basic_string_view<value_type> __x)
1065 {
1066 _M_concat(__x);
1067 return *this;
1068 }
1069
1070 template<typename _CharT>
1071 inline __detail::_Path2<_CharT*>&
1072 path::operator+=(const _CharT __x)
1073 {
1074 _M_concat(_S_convert(&__x, &__x + 1));
1075 return *this;
1076 }
1077
1078 inline path&
1079 path::make_preferred()
1080 {
1081#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1082 auto __pos = _M_pathname.find(L'/');
1083 while (__pos != _M_pathname.npos)
1084 {
1085 _M_pathname[__pos] = preferred_separator;
1086 __pos = _M_pathname.find(L'/', __pos);
1087 }
1088#endif
1089 return *this;
1090 }
1091
1092 inline void path::swap(path& __rhs) noexcept
1093 {
1094 _M_pathname.swap(s&: __rhs._M_pathname);
1095 _M_cmpts.swap(l&: __rhs._M_cmpts);
1096 }
1097
1098 /// @cond undocumented
1099 template<typename _CharT, typename _Traits, typename _Allocator>
1100 std::basic_string<_CharT, _Traits, _Allocator>
1101 path::_S_str_convert(basic_string_view<value_type> __str,
1102 const _Allocator& __a)
1103 {
1104 static_assert(!is_same_v<_CharT, value_type>);
1105
1106 using _WString = basic_string<_CharT, _Traits, _Allocator>;
1107
1108 if (__str.size() == 0)
1109 return _WString(__a);
1110
1111#ifndef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1112 string_view __u8str = __str;
1113#else
1114 // First convert native string from UTF-16 to to UTF-8.
1115 // XXX This assumes that the execution wide-character set is UTF-16.
1116 std::codecvt_utf8_utf16<value_type> __cvt;
1117
1118 using _CharAlloc = __alloc_rebind<_Allocator, char>;
1119 using _String = basic_string<char, char_traits<char>, _CharAlloc>;
1120 _String __u8str{_CharAlloc{__a}};
1121 const value_type* __wfirst = __str.data();
1122 const value_type* __wlast = __wfirst + __str.size();
1123 if (!__str_codecvt_out_all(__wfirst, __wlast, __u8str, __cvt))
1124 __detail::__throw_conversion_error();
1125 if constexpr (is_same_v<_CharT, char>)
1126 return __u8str; // XXX assumes native ordinary encoding is UTF-8.
1127 else
1128#endif
1129 {
1130 const char* __first = __u8str.data();
1131 const char* __last = __first + __u8str.size();
1132
1133 // Convert UTF-8 string to requested format.
1134#ifdef _GLIBCXX_USE_CHAR8_T
1135 if constexpr (is_same_v<_CharT, char8_t>)
1136 return _WString(__first, __last, __a);
1137 else
1138#endif
1139 {
1140 // Convert UTF-8 to wide string.
1141 _WString __wstr(__a);
1142 path::_Codecvt<_CharT> __cvt;
1143 if (__str_codecvt_in_all(__first, __last, __wstr, __cvt))
1144 return __wstr;
1145 }
1146 }
1147 __detail::__throw_conversion_error();
1148 }
1149 /// @endcond
1150
1151 template<typename _CharT, typename _Traits, typename _Allocator>
1152 inline basic_string<_CharT, _Traits, _Allocator>
1153 path::string(const _Allocator& __a) const
1154 {
1155 if constexpr (is_same_v<_CharT, value_type>)
1156 return { _M_pathname.c_str(), _M_pathname.length(), __a };
1157 else
1158 return _S_str_convert<_CharT, _Traits>(_M_pathname, __a);
1159 }
1160
1161 inline std::string
1162 path::string() const { return string<char>(); }
1163
1164#if _GLIBCXX_USE_WCHAR_T
1165 inline std::wstring
1166 path::wstring() const { return string<wchar_t>(); }
1167#endif
1168
1169#ifdef _GLIBCXX_USE_CHAR8_T
1170 inline std::u8string
1171 path::u8string() const { return string<char8_t>(); }
1172#else
1173 inline std::string
1174 path::u8string() const
1175 {
1176#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1177 std::string __str;
1178 // convert from native wide encoding (assumed to be UTF-16) to UTF-8
1179 std::codecvt_utf8_utf16<value_type> __cvt;
1180 const value_type* __first = _M_pathname.data();
1181 const value_type* __last = __first + _M_pathname.size();
1182 if (__str_codecvt_out_all(__first, __last, __str, __cvt))
1183 return __str;
1184 __detail::__throw_conversion_error();
1185#else
1186 return _M_pathname;
1187#endif
1188 }
1189#endif // _GLIBCXX_USE_CHAR8_T
1190
1191 inline std::u16string
1192 path::u16string() const { return string<char16_t>(); }
1193
1194 inline std::u32string
1195 path::u32string() const { return string<char32_t>(); }
1196
1197 template<typename _CharT, typename _Traits, typename _Allocator>
1198 inline std::basic_string<_CharT, _Traits, _Allocator>
1199 path::generic_string(const _Allocator& __a) const
1200 {
1201#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1202 const value_type __slash = L'/';
1203#else
1204 const value_type __slash = '/';
1205#endif
1206 using _Alloc2 = typename allocator_traits<_Allocator>::template
1207 rebind_alloc<value_type>;
1208 basic_string<value_type, char_traits<value_type>, _Alloc2> __str(__a);
1209
1210 if (_M_type() == _Type::_Root_dir)
1211 __str.assign(1, __slash);
1212 else
1213 {
1214 __str.reserve(_M_pathname.size());
1215 bool __add_slash = false;
1216 for (auto& __elem : *this)
1217 {
1218#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1219 if (__elem._M_type() == _Type::_Root_dir)
1220 {
1221 __str += __slash;
1222 continue;
1223 }
1224#endif
1225 if (__add_slash)
1226 __str += __slash;
1227 __str += basic_string_view<value_type>(__elem._M_pathname);
1228 __add_slash = __elem._M_type() == _Type::_Filename;
1229 }
1230 }
1231
1232 if constexpr (is_same_v<_CharT, value_type>)
1233 return __str;
1234 else
1235 return _S_str_convert<_CharT, _Traits>(__str, __a);
1236 }
1237
1238 inline std::string
1239 path::generic_string() const
1240 { return generic_string<char>(); }
1241
1242#if _GLIBCXX_USE_WCHAR_T
1243 inline std::wstring
1244 path::generic_wstring() const
1245 { return generic_string<wchar_t>(); }
1246#endif
1247
1248#ifdef _GLIBCXX_USE_CHAR8_T
1249 inline std::u8string
1250 path::generic_u8string() const
1251 { return generic_string<char8_t>(); }
1252#else
1253 inline std::string
1254 path::generic_u8string() const
1255 { return generic_string(); }
1256#endif
1257
1258 inline std::u16string
1259 path::generic_u16string() const
1260 { return generic_string<char16_t>(); }
1261
1262 inline std::u32string
1263 path::generic_u32string() const
1264 { return generic_string<char32_t>(); }
1265
1266 inline int
1267 path::compare(const string_type& __s) const noexcept
1268 { return compare(s: basic_string_view<value_type>(__s)); }
1269
1270 inline int
1271 path::compare(const value_type* __s) const noexcept
1272 { return compare(s: basic_string_view<value_type>(__s)); }
1273
1274 inline path
1275 path::filename() const
1276 {
1277 if (empty())
1278 return {};
1279 else if (_M_type() == _Type::_Filename)
1280 return *this;
1281 else if (_M_type() == _Type::_Multi)
1282 {
1283 if (_M_pathname.back() == preferred_separator)
1284 return {};
1285 auto __last = --end();
1286 if (__last->_M_type() == _Type::_Filename)
1287 return *__last;
1288 }
1289 return {};
1290 }
1291
1292 inline path
1293 path::stem() const
1294 {
1295 auto ext = _M_find_extension();
1296 if (ext.first && ext.second != 0)
1297 return path{ext.first->substr(pos: 0, n: ext.second)};
1298 return {};
1299 }
1300
1301 inline path
1302 path::extension() const
1303 {
1304 auto ext = _M_find_extension();
1305 if (ext.first && ext.second != string_type::npos)
1306 return path{ext.first->substr(pos: ext.second)};
1307 return {};
1308 }
1309
1310 inline bool
1311 path::has_stem() const noexcept
1312 {
1313 auto ext = _M_find_extension();
1314 return ext.first && ext.second != 0;
1315 }
1316
1317 inline bool
1318 path::has_extension() const noexcept
1319 {
1320 auto ext = _M_find_extension();
1321 return ext.first && ext.second != string_type::npos;
1322 }
1323
1324 inline bool
1325 path::is_absolute() const noexcept
1326 {
1327#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1328 return has_root_name() && has_root_directory();
1329#else
1330 return has_root_directory();
1331#endif
1332 }
1333
1334 inline path::iterator
1335 path::begin() const noexcept
1336 {
1337 if (_M_type() == _Type::_Multi)
1338 return iterator(this, _M_cmpts.begin());
1339 return iterator(this, empty());
1340 }
1341
1342 inline path::iterator
1343 path::end() const noexcept
1344 {
1345 if (_M_type() == _Type::_Multi)
1346 return iterator(this, _M_cmpts.end());
1347 return iterator(this, true);
1348 }
1349
1350 inline path::iterator&
1351 path::iterator::operator++() noexcept
1352 {
1353 __glibcxx_assert(_M_path != nullptr);
1354 if (_M_is_multi())
1355 {
1356 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.end());
1357 ++_M_cur;
1358 }
1359 else
1360 {
1361 __glibcxx_assert(!_M_at_end);
1362 _M_at_end = true;
1363 }
1364 return *this;
1365 }
1366
1367 inline path::iterator&
1368 path::iterator::operator--() noexcept
1369 {
1370 __glibcxx_assert(_M_path != nullptr);
1371 if (_M_is_multi())
1372 {
1373 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.begin());
1374 --_M_cur;
1375 }
1376 else
1377 {
1378 __glibcxx_assert(_M_at_end);
1379 _M_at_end = false;
1380 }
1381 return *this;
1382 }
1383
1384 inline path::iterator::reference
1385 path::iterator::operator*() const noexcept
1386 {
1387 __glibcxx_assert(_M_path != nullptr);
1388 if (_M_is_multi())
1389 {
1390 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.end());
1391 return *_M_cur;
1392 }
1393 return *_M_path;
1394 }
1395
1396 inline bool
1397 path::iterator::_M_equals(iterator __rhs) const noexcept
1398 {
1399 if (_M_path != __rhs._M_path)
1400 return false;
1401 if (_M_path == nullptr)
1402 return true;
1403 if (_M_is_multi())
1404 return _M_cur == __rhs._M_cur;
1405 return _M_at_end == __rhs._M_at_end;
1406 }
1407
1408 // Define this now that path and path::iterator are complete.
1409 // It needs to consider the string_view(Range&&) constructor during
1410 // overload resolution, which depends on whether range<path> is satisfied,
1411 // which depends on whether path::iterator is complete.
1412 inline int
1413 path::_S_compare(const path& __lhs, const path& __rhs) noexcept
1414 { return __lhs.compare(p: __rhs); }
1415
1416 /// @} group filesystem
1417_GLIBCXX_END_NAMESPACE_CXX11
1418} // namespace filesystem
1419
1420/// @cond undocumented
1421
1422inline ptrdiff_t
1423distance(filesystem::path::iterator __first, filesystem::path::iterator __last)
1424noexcept
1425{ return __path_iter_distance(__first, __last); }
1426
1427template<typename _Distance>
1428 inline void
1429 advance(filesystem::path::iterator& __i, _Distance __n) noexcept
1430 { __path_iter_advance(__i, n: static_cast<ptrdiff_t>(__n)); }
1431
1432extern template class __shared_ptr<const filesystem::filesystem_error::_Impl>;
1433
1434/// @endcond
1435
1436// _GLIBCXX_RESOLVE_LIB_DEFECTS
1437// 3657. std::hash<std::filesystem::path> is not enabled
1438template<>
1439 struct hash<filesystem::path>
1440 {
1441 size_t
1442 operator()(const filesystem::path& __p) const noexcept
1443 { return filesystem::hash_value(__p); }
1444 };
1445
1446_GLIBCXX_END_NAMESPACE_VERSION
1447} // namespace std
1448
1449#endif // C++17
1450
1451#endif // _GLIBCXX_FS_PATH_H
1452