1// Class filesystem::path -*- C++ -*-
2
3// Copyright (C) 2014-2021 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 <utility>
36#include <type_traits>
37#include <locale>
38#include <iosfwd>
39#include <iomanip>
40#include <codecvt>
41#include <string_view>
42#include <system_error>
43#include <bits/stl_algobase.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# include <algorithm>
56#endif
57
58namespace std _GLIBCXX_VISIBILITY(default)
59{
60_GLIBCXX_BEGIN_NAMESPACE_VERSION
61
62namespace filesystem
63{
64_GLIBCXX_BEGIN_NAMESPACE_CXX11
65
66 class path;
67
68 /// @cond undocumented
69namespace __detail
70{
71 /// @addtogroup filesystem
72 /// @{
73 template<typename _CharT>
74 inline constexpr bool __is_encoded_char = false;
75 template<>
76 inline constexpr bool __is_encoded_char<char> = true;
77#ifdef _GLIBCXX_USE_CHAR8_T
78 template<>
79 inline constexpr bool __is_encoded_char<char8_t> = true;
80#endif
81#if _GLIBCXX_USE_WCHAR_T
82 template<>
83 inline constexpr bool __is_encoded_char<wchar_t> = true;
84#endif
85 template<>
86 inline constexpr bool __is_encoded_char<char16_t> = true;
87 template<>
88 inline constexpr bool __is_encoded_char<char32_t> = true;
89
90#if __cpp_concepts >= 201907L
91 template<typename _Iter>
92 using __safe_iterator_traits = std::iterator_traits<_Iter>;
93#else
94 template<typename _Iter>
95 struct __safe_iterator_traits : std::iterator_traits<_Iter>
96 { };
97
98 // Protect against ill-formed iterator_traits specializations in C++17
99 template<> struct __safe_iterator_traits<void*> { };
100 template<> struct __safe_iterator_traits<const void*> { };
101 template<> struct __safe_iterator_traits<volatile void*> { };
102 template<> struct __safe_iterator_traits<const volatile void*> { };
103#endif
104
105 template<typename _Iter_traits, typename = void>
106 struct __is_path_iter_src
107 : false_type
108 { };
109
110 template<typename _Iter_traits>
111 struct __is_path_iter_src<_Iter_traits,
112 void_t<typename _Iter_traits::value_type>>
113 : bool_constant<__is_encoded_char<typename _Iter_traits::value_type>>
114 { };
115
116 template<typename _Source>
117 inline constexpr bool __is_path_src
118 = __is_path_iter_src<iterator_traits<decay_t<_Source>>>::value;
119
120 template<>
121 inline constexpr bool __is_path_src<path> = false;
122
123 template<>
124 inline constexpr bool __is_path_src<volatile path> = false;
125
126 template<>
127 inline constexpr bool __is_path_src<void*> = false;
128
129 template<>
130 inline constexpr bool __is_path_src<const void*> = false;
131
132 template<>
133 inline constexpr bool __is_path_src<volatile void*> = false;
134
135 template<>
136 inline constexpr bool __is_path_src<const volatile void*> = false;
137
138 template<typename _CharT, typename _Traits, typename _Alloc>
139 inline constexpr bool
140 __is_path_src<basic_string<_CharT, _Traits, _Alloc>>
141 = __is_encoded_char<_CharT>;
142
143 template<typename _CharT, typename _Traits>
144 inline constexpr bool
145 __is_path_src<basic_string_view<_CharT, _Traits>>
146 = __is_encoded_char<_CharT>;
147
148 // SFINAE constraint for Source parameters as required by [fs.path.req].
149 template<typename _Tp>
150 using _Path = enable_if_t<__is_path_src<_Tp>, path>;
151
152 // SFINAE constraint for InputIterator parameters as required by [fs.req].
153 template<typename _Iter, typename _Tr = __safe_iterator_traits<_Iter>>
154 using _Path2 = enable_if_t<__is_path_iter_src<_Tr>::value, path>;
155
156 // The __effective_range overloads convert a Source parameter into
157 // either a basic_string_view or basic_string containing the
158 // effective range of the Source, as defined in [fs.path.req].
159
160 template<typename _CharT, typename _Traits, typename _Alloc>
161 inline basic_string_view<_CharT, _Traits>
162 __effective_range(const basic_string<_CharT, _Traits, _Alloc>& __source)
163 { return __source; }
164
165 template<typename _CharT, typename _Traits>
166 inline const basic_string_view<_CharT, _Traits>&
167 __effective_range(const basic_string_view<_CharT, _Traits>& __source)
168 { return __source; }
169
170 template<typename _Source>
171 inline auto
172 __effective_range(const _Source& __source)
173 {
174 if constexpr (is_pointer_v<decay_t<_Source>>)
175 return basic_string_view{&*__source};
176 else
177 {
178 // _Source is an input iterator that iterates over an NTCTS.
179 // Create a basic_string by reading until the null character.
180 using value_type
181 = typename iterator_traits<_Source>::value_type;
182 basic_string<value_type> __str;
183 _Source __it = __source;
184 for (value_type __ch = *__it; __ch != value_type(); __ch = *++__it)
185 __str.push_back(__ch);
186 return __str;
187 }
188 }
189
190 // The value type of a Source parameter's effective range.
191 template<typename _Tp>
192 using __value_t = typename remove_reference_t<
193 decltype(__detail::__effective_range(std::declval<_Tp>()))>::value_type;
194
195 // SFINAE helper to check that an effective range has value_type char,
196 // as required by path constructors taking a std::locale parameter.
197 // The type _Tp must have already been checked by _Path<Tp> or _Path2<_Tp>.
198 template<typename _Tp, typename _Val = __value_t<_Tp>>
199 using __value_type_is_char
200 = std::enable_if_t<std::is_same_v<_Val, char>, _Val>;
201
202 // As above, but also allows char8_t, as required by u8path
203 // C++20 [depr.fs.path.factory]
204 template<typename _Tp, typename _Val = __value_t<_Tp>>
205 using __value_type_is_char_or_char8_t
206 = std::enable_if_t<std::is_same_v<_Val, char>
207#ifdef _GLIBCXX_USE_CHAR8_T
208 || std::is_same_v<_Val, char8_t>
209#endif
210 , _Val>;
211
212 // Create a string or string view from an iterator range.
213 template<typename _InputIterator>
214 inline auto
215 __string_from_range(_InputIterator __first, _InputIterator __last)
216 {
217 using _EcharT
218 = typename std::iterator_traits<_InputIterator>::value_type;
219 static_assert(__is_encoded_char<_EcharT>);
220
221#if __cpp_lib_concepts
222 constexpr bool __contiguous = std::contiguous_iterator<_InputIterator>;
223#else
224 constexpr bool __contiguous
225 = is_pointer_v<decltype(std::__niter_base(__first))>;
226#endif
227 if constexpr (__contiguous)
228 {
229 // For contiguous iterators we can just return a string view.
230 const auto* __f = std::__to_address(std::__niter_base(__first));
231 const auto* __l = std::__to_address(std::__niter_base(__last));
232 return basic_string_view<_EcharT>(__f, __l - __f);
233 }
234 else
235 // Conversion requires contiguous characters, so create a string.
236 return basic_string<_EcharT>(__first, __last);
237 }
238
239 /// @} group filesystem
240} // namespace __detail
241 /// @endcond
242
243 /// @addtogroup filesystem
244 /// @{
245
246 /// A filesystem path
247 /// @ingroup filesystem
248 class path
249 {
250 public:
251#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
252 using value_type = wchar_t;
253 static constexpr value_type preferred_separator = L'\\';
254#else
255# ifdef _GLIBCXX_DOXYGEN
256 /// Windows uses wchar_t for path::value_type, POSIX uses char.
257 using value_type = __os_dependent__;
258# else
259 using value_type = char;
260# endif
261 static constexpr value_type preferred_separator = '/';
262#endif
263 using string_type = std::basic_string<value_type>;
264
265 /// path::format is ignored in this implementation
266 enum format : unsigned char { native_format, generic_format, auto_format };
267
268 // constructors and destructor
269
270 path() noexcept { }
271
272 path(const path& __p) = default;
273
274 path(path&& __p)
275#if _GLIBCXX_USE_CXX11_ABI || _GLIBCXX_FULLY_DYNAMIC_STRING == 0
276 noexcept
277#endif
278 : _M_pathname(std::move(__p._M_pathname)),
279 _M_cmpts(std::move(__p._M_cmpts))
280 { __p.clear(); }
281
282 path(string_type&& __source, format = auto_format)
283 : _M_pathname(std::move(__source))
284 { _M_split_cmpts(); }
285
286 template<typename _Source,
287 typename _Require = __detail::_Path<_Source>>
288 path(_Source const& __source, format = auto_format)
289 : _M_pathname(_S_convert(__detail::__effective_range(__source)))
290 { _M_split_cmpts(); }
291
292 template<typename _InputIterator,
293 typename _Require = __detail::_Path2<_InputIterator>>
294 path(_InputIterator __first, _InputIterator __last, format = auto_format)
295 : _M_pathname(_S_convert(__detail::__string_from_range(__first, __last)))
296 { _M_split_cmpts(); }
297
298 template<typename _Source,
299 typename _Require = __detail::_Path<_Source>,
300 typename _Require2 = __detail::__value_type_is_char<_Source>>
301 path(_Source const& __src, const locale& __loc, format = auto_format)
302 : _M_pathname(_S_convert_loc(__detail::__effective_range(__src), __loc))
303 { _M_split_cmpts(); }
304
305 template<typename _InputIterator,
306 typename _Require = __detail::_Path2<_InputIterator>,
307 typename _Req2 = __detail::__value_type_is_char<_InputIterator>>
308 path(_InputIterator __first, _InputIterator __last, const locale& __loc,
309 format = auto_format)
310 : _M_pathname(_S_convert_loc(__first, __last, __loc))
311 { _M_split_cmpts(); }
312
313 ~path() = default;
314
315 // assignments
316
317 path& operator=(const path&);
318 path& operator=(path&&) noexcept;
319 path& operator=(string_type&& __source);
320 path& assign(string_type&& __source);
321
322 template<typename _Source>
323 __detail::_Path<_Source>&
324 operator=(_Source const& __source)
325 { return *this = path(__source); }
326
327 template<typename _Source>
328 __detail::_Path<_Source>&
329 assign(_Source const& __source)
330 { return *this = path(__source); }
331
332 template<typename _InputIterator>
333 __detail::_Path2<_InputIterator>&
334 assign(_InputIterator __first, _InputIterator __last)
335 { return *this = path(__first, __last); }
336
337 // appends
338
339 path& operator/=(const path& __p);
340
341 template<typename _Source>
342 __detail::_Path<_Source>&
343 operator/=(_Source const& __source)
344 {
345 _M_append(_S_convert(__detail::__effective_range(__source)));
346 return *this;
347 }
348
349 template<typename _Source>
350 __detail::_Path<_Source>&
351 append(_Source const& __source)
352 {
353 _M_append(_S_convert(__detail::__effective_range(__source)));
354 return *this;
355 }
356
357 template<typename _InputIterator>
358 __detail::_Path2<_InputIterator>&
359 append(_InputIterator __first, _InputIterator __last)
360 {
361 _M_append(_S_convert(__detail::__string_from_range(__first, __last)));
362 return *this;
363 }
364
365 // concatenation
366
367 path& operator+=(const path& __x);
368 path& operator+=(const string_type& __x);
369 path& operator+=(const value_type* __x);
370 path& operator+=(value_type __x);
371 path& operator+=(basic_string_view<value_type> __x);
372
373 template<typename _Source>
374 __detail::_Path<_Source>&
375 operator+=(_Source const& __x) { return concat(__x); }
376
377 template<typename _CharT>
378 __detail::_Path2<_CharT*>&
379 operator+=(_CharT __x);
380
381 template<typename _Source>
382 __detail::_Path<_Source>&
383 concat(_Source const& __x)
384 {
385 _M_concat(_S_convert(__detail::__effective_range(__x)));
386 return *this;
387 }
388
389 template<typename _InputIterator>
390 __detail::_Path2<_InputIterator>&
391 concat(_InputIterator __first, _InputIterator __last)
392 {
393 _M_concat(_S_convert(__detail::__string_from_range(__first, __last)));
394 return *this;
395 }
396
397 // modifiers
398
399 void clear() noexcept { _M_pathname.clear(); _M_split_cmpts(); }
400
401 path& make_preferred();
402 path& remove_filename();
403 path& replace_filename(const path& __replacement);
404 path& replace_extension(const path& __replacement = path());
405
406 void swap(path& __rhs) noexcept;
407
408 // native format observers
409
410 const string_type& native() const noexcept { return _M_pathname; }
411 const value_type* c_str() const noexcept { return _M_pathname.c_str(); }
412 operator string_type() const { return _M_pathname; }
413
414 template<typename _CharT, typename _Traits = std::char_traits<_CharT>,
415 typename _Allocator = std::allocator<_CharT>>
416 std::basic_string<_CharT, _Traits, _Allocator>
417 string(const _Allocator& __a = _Allocator()) const;
418
419 std::string string() const;
420#if _GLIBCXX_USE_WCHAR_T
421 std::wstring wstring() const;
422#endif
423#ifdef _GLIBCXX_USE_CHAR8_T
424 __attribute__((__abi_tag__("__u8")))
425 std::u8string u8string() const;
426#else
427 std::string u8string() const;
428#endif // _GLIBCXX_USE_CHAR8_T
429 std::u16string u16string() const;
430 std::u32string u32string() const;
431
432 // generic format observers
433 template<typename _CharT, typename _Traits = std::char_traits<_CharT>,
434 typename _Allocator = std::allocator<_CharT>>
435 std::basic_string<_CharT, _Traits, _Allocator>
436 generic_string(const _Allocator& __a = _Allocator()) const;
437
438 std::string generic_string() const;
439#if _GLIBCXX_USE_WCHAR_T
440 std::wstring generic_wstring() const;
441#endif
442#ifdef _GLIBCXX_USE_CHAR8_T
443 __attribute__((__abi_tag__("__u8")))
444 std::u8string generic_u8string() const;
445#else
446 std::string generic_u8string() const;
447#endif // _GLIBCXX_USE_CHAR8_T
448 std::u16string generic_u16string() const;
449 std::u32string generic_u32string() const;
450
451 // compare
452
453 int compare(const path& __p) const noexcept;
454 int compare(const string_type& __s) const noexcept;
455 int compare(const value_type* __s) const noexcept;
456 int compare(basic_string_view<value_type> __s) const noexcept;
457
458 // decomposition
459
460 path root_name() const;
461 path root_directory() const;
462 path root_path() const;
463 path relative_path() const;
464 path parent_path() const;
465 path filename() const;
466 path stem() const;
467 path extension() const;
468
469 // query
470
471 [[nodiscard]] bool empty() const noexcept { return _M_pathname.empty(); }
472 bool has_root_name() const noexcept;
473 bool has_root_directory() const noexcept;
474 bool has_root_path() const noexcept;
475 bool has_relative_path() const noexcept;
476 bool has_parent_path() const noexcept;
477 bool has_filename() const noexcept;
478 bool has_stem() const noexcept;
479 bool has_extension() const noexcept;
480 bool is_absolute() const noexcept;
481 bool is_relative() const noexcept { return !is_absolute(); }
482
483 // generation
484 path lexically_normal() const;
485 path lexically_relative(const path& base) const;
486 path lexically_proximate(const path& base) const;
487
488 // iterators
489 class iterator;
490 using const_iterator = iterator;
491
492 iterator begin() const;
493 iterator end() const;
494
495 /// Write a path to a stream
496 template<typename _CharT, typename _Traits>
497 friend std::basic_ostream<_CharT, _Traits>&
498 operator<<(std::basic_ostream<_CharT, _Traits>& __os, const path& __p)
499 {
500 __os << std::quoted(__p.string<_CharT, _Traits>());
501 return __os;
502 }
503
504 /// Read a path from a stream
505 template<typename _CharT, typename _Traits>
506 friend std::basic_istream<_CharT, _Traits>&
507 operator>>(std::basic_istream<_CharT, _Traits>& __is, path& __p)
508 {
509 std::basic_string<_CharT, _Traits> __tmp;
510 if (__is >> std::quoted(__tmp))
511 __p = std::move(__tmp);
512 return __is;
513 }
514
515 // non-member operators
516
517 /// Compare paths
518 friend bool operator==(const path& __lhs, const path& __rhs) noexcept
519 { return path::_S_compare(__lhs, __rhs) == 0; }
520
521#if __cpp_lib_three_way_comparison
522 /// Compare paths
523 friend strong_ordering
524 operator<=>(const path& __lhs, const path& __rhs) noexcept
525 { return path::_S_compare(__lhs, __rhs) <=> 0; }
526#else
527 /// Compare paths
528 friend bool operator!=(const path& __lhs, const path& __rhs) noexcept
529 { return !(__lhs == __rhs); }
530
531 /// Compare paths
532 friend bool operator<(const path& __lhs, const path& __rhs) noexcept
533 { return __lhs.compare(__rhs) < 0; }
534
535 /// Compare paths
536 friend bool operator<=(const path& __lhs, const path& __rhs) noexcept
537 { return !(__rhs < __lhs); }
538
539 /// Compare paths
540 friend bool operator>(const path& __lhs, const path& __rhs) noexcept
541 { return __rhs < __lhs; }
542
543 /// Compare paths
544 friend bool operator>=(const path& __lhs, const path& __rhs) noexcept
545 { return !(__lhs < __rhs); }
546#endif
547
548 /// Append one path to another
549 friend path operator/(const path& __lhs, const path& __rhs)
550 {
551 path __result(__lhs);
552 __result /= __rhs;
553 return __result;
554 }
555
556 private:
557 enum class _Type : unsigned char {
558 _Multi = 0, _Root_name, _Root_dir, _Filename
559 };
560
561 path(basic_string_view<value_type> __str, _Type __type);
562
563 enum class _Split { _Stem, _Extension };
564
565 void _M_append(basic_string_view<value_type>);
566 void _M_concat(basic_string_view<value_type>);
567
568 pair<const string_type*, size_t> _M_find_extension() const noexcept;
569
570 // path::_S_convert creates a basic_string<value_type> or
571 // basic_string_view<value_type> from a range (either the effective
572 // range of a Source parameter, or a pair of InputIterator parameters),
573 // performing the conversions required by [fs.path.type.cvt].
574 // If the value_type of the range value type is path::value_type,
575 // no encoding conversion is performed. If the range is contiguous
576 // a string_view
577
578 static string_type
579 _S_convert(string_type __str)
580 { return __str; }
581
582 template<typename _Tp>
583 static auto
584 _S_convert(const _Tp& __str)
585 {
586 if constexpr (is_same_v<_Tp, string_type>)
587 return __str;
588 else if constexpr (is_same_v<_Tp, basic_string_view<value_type>>)
589 return __str;
590 else if constexpr (is_same_v<typename _Tp::value_type, value_type>)
591 return basic_string_view<value_type>(__str.data(), __str.size());
592 else
593 return _S_convert(__str.data(), __str.data() + __str.size());
594 }
595
596 template<typename _EcharT>
597 static auto
598 _S_convert(const _EcharT* __first, const _EcharT* __last);
599
600 static string_type
601 _S_convert_loc(const char* __first, const char* __last,
602 const std::locale& __loc);
603
604 template<typename _Iter>
605 static string_type
606 _S_convert_loc(_Iter __first, _Iter __last, const std::locale& __loc)
607 {
608 const auto __s = __detail::__string_from_range(__first, __last);
609 return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
610 }
611
612 template<typename _Tp>
613 static string_type
614 _S_convert_loc(const _Tp& __s, const std::locale& __loc)
615 {
616 return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
617 }
618
619 template<typename _CharT, typename _Traits, typename _Allocator>
620 static basic_string<_CharT, _Traits, _Allocator>
621 _S_str_convert(basic_string_view<value_type>, const _Allocator&);
622
623 // Returns lhs.compare(rhs), but defined after path::iterator is complete.
624 __attribute__((__always_inline__))
625 static int
626 _S_compare(const path& __lhs, const path& __rhs) noexcept;
627
628 void _M_split_cmpts();
629
630 _Type _M_type() const noexcept { return _M_cmpts.type(); }
631
632 string_type _M_pathname;
633
634 struct _Cmpt;
635
636 struct _List
637 {
638 using value_type = _Cmpt;
639 using iterator = value_type*;
640 using const_iterator = const value_type*;
641
642 _List();
643 _List(const _List&);
644 _List(_List&&) = default;
645 _List& operator=(const _List&);
646 _List& operator=(_List&&) = default;
647 ~_List() = default;
648
649 _Type type() const noexcept
650 { return _Type(reinterpret_cast<uintptr_t>(_M_impl.get()) & 0x3); }
651
652 void type(_Type) noexcept;
653
654 int size() const noexcept; // zero unless type() == _Type::_Multi
655 bool empty() const noexcept; // true unless type() == _Type::_Multi
656 void clear();
657 void swap(_List& __l) noexcept { _M_impl.swap(u&: __l._M_impl); }
658 int capacity() const noexcept;
659 void reserve(int, bool); ///< @pre type() == _Type::_Multi
660
661 // All the member functions below here have a precondition !empty()
662 // (and they should only be called from within the library).
663
664 iterator begin() noexcept;
665 iterator end() noexcept;
666 const_iterator begin() const noexcept;
667 const_iterator end() const noexcept;
668
669 value_type& front() noexcept;
670 value_type& back() noexcept;
671 const value_type& front() const noexcept;
672 const value_type& back() const noexcept;
673
674 void pop_back();
675 void _M_erase_from(const_iterator __pos); // erases [__pos,end())
676
677 struct _Impl;
678 struct _Impl_deleter
679 {
680 void operator()(_Impl*) const noexcept;
681 };
682 unique_ptr<_Impl, _Impl_deleter> _M_impl;
683 };
684 _List _M_cmpts;
685
686 struct _Parser;
687 };
688
689 /// @{
690 /// @relates std::filesystem::path
691
692 inline void swap(path& __lhs, path& __rhs) noexcept { __lhs.swap(__rhs); }
693
694 size_t hash_value(const path& __p) noexcept;
695
696 /// @}
697
698 /// Exception type thrown by the Filesystem library
699 class filesystem_error : public std::system_error
700 {
701 public:
702 filesystem_error(const string& __what_arg, error_code __ec);
703
704 filesystem_error(const string& __what_arg, const path& __p1,
705 error_code __ec);
706
707 filesystem_error(const string& __what_arg, const path& __p1,
708 const path& __p2, error_code __ec);
709
710 filesystem_error(const filesystem_error&) = default;
711 filesystem_error& operator=(const filesystem_error&) = default;
712
713 // No move constructor or assignment operator.
714 // Copy rvalues instead, so that _M_impl is not left empty.
715
716 ~filesystem_error();
717
718 const path& path1() const noexcept;
719 const path& path2() const noexcept;
720 const char* what() const noexcept;
721
722 private:
723 struct _Impl;
724 std::__shared_ptr<const _Impl> _M_impl;
725 };
726
727 /// @cond undocumented
728namespace __detail
729{
730 [[noreturn]] inline void
731 __throw_conversion_error()
732 {
733 _GLIBCXX_THROW_OR_ABORT(filesystem_error(
734 "Cannot convert character sequence",
735 std::make_error_code(errc::illegal_byte_sequence)));
736 }
737
738#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
739 template<typename _Tp>
740 inline std::wstring
741 __wstr_from_utf8(const _Tp& __str)
742 {
743 static_assert(std::is_same_v<typename _Tp::value_type, char>);
744 std::wstring __wstr;
745 // XXX This assumes native wide encoding is UTF-16.
746 std::codecvt_utf8_utf16<wchar_t> __wcvt;
747 const auto __p = __str.data();
748 if (!__str_codecvt_in_all(__p, __p + __str.size(), __wstr, __wcvt))
749 __detail::__throw_conversion_error();
750 return __wstr;
751 }
752#endif
753
754} // namespace __detail
755 /// @endcond
756
757
758 /** Create a path from a UTF-8-encoded sequence of char
759 *
760 * @relates std::filesystem::path
761 */
762 template<typename _InputIterator,
763 typename _Require = __detail::_Path2<_InputIterator>,
764 typename _CharT
765 = __detail::__value_type_is_char_or_char8_t<_InputIterator>>
766 inline path
767 u8path(_InputIterator __first, _InputIterator __last)
768 {
769#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
770 if constexpr (is_same_v<_CharT, char>)
771 return path{ __detail::__wstr_from_utf8(
772 __detail::__string_from_range(__first, __last)) };
773 else
774 return path{ __first, __last }; // constructor handles char8_t
775#else
776 // This assumes native normal encoding is UTF-8.
777 return path{ __first, __last };
778#endif
779 }
780
781 /** Create a path from a UTF-8-encoded sequence of char
782 *
783 * @relates std::filesystem::path
784 */
785 template<typename _Source,
786 typename _Require = __detail::_Path<_Source>,
787 typename _CharT = __detail::__value_type_is_char_or_char8_t<_Source>>
788 inline path
789 u8path(const _Source& __source)
790 {
791#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
792 if constexpr (is_same_v<_CharT, char>)
793 return path{ __detail::__wstr_from_utf8(
794 __detail::__effective_range(__source)) };
795 else
796 return path{ __source }; // constructor handles char8_t
797#else
798 // This assumes native normal encoding is UTF-8.
799 return path{ __source };
800#endif
801 }
802
803 /// @cond undocumented
804
805 struct path::_Cmpt : path
806 {
807 _Cmpt(basic_string_view<value_type> __s, _Type __t, size_t __pos);
808
809 _Cmpt() : _M_pos(-1) { }
810
811 size_t _M_pos;
812 };
813
814 template<typename _EcharT>
815 auto
816 path::_S_convert(const _EcharT* __f, const _EcharT* __l)
817 {
818 static_assert(__detail::__is_encoded_char<_EcharT>);
819
820 if constexpr (is_same_v<_EcharT, value_type>)
821 return basic_string_view<value_type>(__f, __l - __f);
822#if !defined _GLIBCXX_FILESYSTEM_IS_WINDOWS && defined _GLIBCXX_USE_CHAR8_T
823 else if constexpr (is_same_v<_EcharT, char8_t>)
824 // For POSIX converting from char8_t to char is also 'noconv'
825 return string_view(reinterpret_cast<const char*>(__f), __l - __f);
826#endif
827 else
828 {
829#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
830 std::wstring __wstr;
831 if constexpr (is_same_v<_EcharT, char>)
832 {
833 struct _UCvt : std::codecvt<wchar_t, char, std::mbstate_t>
834 { } __cvt;
835 if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
836 return __wstr;
837 }
838#ifdef _GLIBCXX_USE_CHAR8_T
839 else if constexpr (is_same_v<_EcharT, char8_t>)
840 {
841 const auto __f2 = reinterpret_cast<const char*>(__f);
842 return __detail::__wstr_from_utf8(string_view(__f2, __l - __f));
843 }
844#endif
845 else // char16_t or char32_t
846 {
847 struct _UCvt : std::codecvt<_EcharT, char, std::mbstate_t>
848 { } __cvt;
849 std::string __str;
850 if (__str_codecvt_out_all(__f, __l, __str, __cvt))
851 return __detail::__wstr_from_utf8(__str);
852 }
853#else // ! windows
854 struct _UCvt : std::codecvt<_EcharT, char, std::mbstate_t>
855 { } __cvt;
856 std::string __str;
857 if (__str_codecvt_out_all(__f, __l, __str, __cvt))
858 return __str;
859#endif
860 __detail::__throw_conversion_error();
861 }
862 }
863
864 /// @endcond
865
866 /// An iterator for the components of a path
867 class path::iterator
868 {
869 public:
870 using difference_type = std::ptrdiff_t;
871 using value_type = path;
872 using reference = const path&;
873 using pointer = const path*;
874 using iterator_category = std::bidirectional_iterator_tag;
875
876 iterator() : _M_path(nullptr), _M_cur(), _M_at_end() { }
877
878 iterator(const iterator&) = default;
879 iterator& operator=(const iterator&) = default;
880
881 reference operator*() const;
882 pointer operator->() const { return std::__addressof(r: **this); }
883
884 iterator& operator++();
885 iterator operator++(int) { auto __tmp = *this; ++*this; return __tmp; }
886
887 iterator& operator--();
888 iterator operator--(int) { auto __tmp = *this; --*this; return __tmp; }
889
890 friend bool operator==(const iterator& __lhs, const iterator& __rhs)
891 { return __lhs._M_equals(__rhs); }
892
893 friend bool operator!=(const iterator& __lhs, const iterator& __rhs)
894 { return !__lhs._M_equals(__rhs); }
895
896 private:
897 friend class path;
898
899 bool _M_is_multi() const { return _M_path->_M_type() == _Type::_Multi; }
900
901 friend difference_type
902 __path_iter_distance(const iterator& __first, const iterator& __last)
903 {
904 __glibcxx_assert(__first._M_path != nullptr);
905 __glibcxx_assert(__first._M_path == __last._M_path);
906 if (__first._M_is_multi())
907 return std::distance(first: __first._M_cur, last: __last._M_cur);
908 else if (__first._M_at_end == __last._M_at_end)
909 return 0;
910 else
911 return __first._M_at_end ? -1 : 1;
912 }
913
914 friend void
915 __path_iter_advance(iterator& __i, difference_type __n)
916 {
917 if (__n == 1)
918 ++__i;
919 else if (__n == -1)
920 --__i;
921 else if (__n != 0)
922 {
923 __glibcxx_assert(__i._M_path != nullptr);
924 __glibcxx_assert(__i._M_is_multi());
925 // __glibcxx_assert(__i._M_path->_M_cmpts.end() - __i._M_cur >= __n);
926 __i._M_cur += __n;
927 }
928 }
929
930 iterator(const path* __path, path::_List::const_iterator __iter)
931 : _M_path(__path), _M_cur(__iter), _M_at_end()
932 { }
933
934 iterator(const path* __path, bool __at_end)
935 : _M_path(__path), _M_cur(), _M_at_end(__at_end)
936 { }
937
938 bool _M_equals(iterator) const;
939
940 const path* _M_path;
941 path::_List::const_iterator _M_cur;
942 bool _M_at_end; // only used when type != _Multi
943 };
944
945
946 inline path&
947 path::operator=(path&& __p) noexcept
948 {
949 if (&__p == this) [[__unlikely__]]
950 return *this;
951
952 _M_pathname = std::move(__p._M_pathname);
953 _M_cmpts = std::move(__p._M_cmpts);
954 __p.clear();
955 return *this;
956 }
957
958 inline path&
959 path::operator=(string_type&& __source)
960 { return *this = path(std::move(__source)); }
961
962 inline path&
963 path::assign(string_type&& __source)
964 { return *this = path(std::move(__source)); }
965
966 inline path&
967 path::operator+=(const string_type& __x)
968 {
969 _M_concat(__x);
970 return *this;
971 }
972
973 inline path&
974 path::operator+=(const value_type* __x)
975 {
976 _M_concat(__x);
977 return *this;
978 }
979
980 inline path&
981 path::operator+=(value_type __x)
982 {
983 _M_concat(basic_string_view<value_type>(&__x, 1));
984 return *this;
985 }
986
987 inline path&
988 path::operator+=(basic_string_view<value_type> __x)
989 {
990 _M_concat(__x);
991 return *this;
992 }
993
994 template<typename _CharT>
995 inline __detail::_Path2<_CharT*>&
996 path::operator+=(const _CharT __x)
997 {
998 _M_concat(_S_convert(&__x, &__x + 1));
999 return *this;
1000 }
1001
1002 inline path&
1003 path::make_preferred()
1004 {
1005#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1006 std::replace(_M_pathname.begin(), _M_pathname.end(), L'/',
1007 preferred_separator);
1008#endif
1009 return *this;
1010 }
1011
1012 inline void path::swap(path& __rhs) noexcept
1013 {
1014 _M_pathname.swap(s&: __rhs._M_pathname);
1015 _M_cmpts.swap(l&: __rhs._M_cmpts);
1016 }
1017
1018 /// @cond undocumented
1019 template<typename _CharT, typename _Traits, typename _Allocator>
1020 std::basic_string<_CharT, _Traits, _Allocator>
1021 path::_S_str_convert(basic_string_view<value_type> __str,
1022 const _Allocator& __a)
1023 {
1024 static_assert(!is_same_v<_CharT, value_type>);
1025
1026 using _WString = basic_string<_CharT, _Traits, _Allocator>;
1027
1028 if (__str.size() == 0)
1029 return _WString(__a);
1030
1031#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1032 // First convert native string from UTF-16 to to UTF-8.
1033 // XXX This assumes that the execution wide-character set is UTF-16.
1034 std::codecvt_utf8_utf16<value_type> __cvt;
1035
1036 using _CharAlloc = __alloc_rebind<_Allocator, char>;
1037 using _String = basic_string<char, char_traits<char>, _CharAlloc>;
1038 _String __u8str{_CharAlloc{__a}};
1039 const value_type* __wfirst = __str.data();
1040 const value_type* __wlast = __wfirst + __str.size();
1041 if (__str_codecvt_out_all(__wfirst, __wlast, __u8str, __cvt)) {
1042 if constexpr (is_same_v<_CharT, char>)
1043 return __u8str; // XXX assumes native ordinary encoding is UTF-8.
1044 else {
1045
1046 const char* __first = __u8str.data();
1047 const char* __last = __first + __u8str.size();
1048#else
1049 const value_type* __first = __str.data();
1050 const value_type* __last = __first + __str.size();
1051#endif
1052
1053 // Convert UTF-8 string to requested format.
1054#ifdef _GLIBCXX_USE_CHAR8_T
1055 if constexpr (is_same_v<_CharT, char8_t>)
1056 return _WString(__first, __last, __a);
1057 else
1058#endif
1059 {
1060 // Convert UTF-8 to wide string.
1061 _WString __wstr(__a);
1062 struct _UCvt : std::codecvt<_CharT, char, std::mbstate_t> { } __cvt;
1063 if (__str_codecvt_in_all(__first, __last, __wstr, __cvt))
1064 return __wstr;
1065 }
1066
1067#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1068 } }
1069#endif
1070 __detail::__throw_conversion_error();
1071 }
1072 /// @endcond
1073
1074 template<typename _CharT, typename _Traits, typename _Allocator>
1075 inline basic_string<_CharT, _Traits, _Allocator>
1076 path::string(const _Allocator& __a) const
1077 {
1078 if constexpr (is_same_v<_CharT, value_type>)
1079 return { _M_pathname.c_str(), _M_pathname.length(), __a };
1080 else
1081 return _S_str_convert<_CharT, _Traits>(_M_pathname, __a);
1082 }
1083
1084 inline std::string
1085 path::string() const { return string<char>(); }
1086
1087#if _GLIBCXX_USE_WCHAR_T
1088 inline std::wstring
1089 path::wstring() const { return string<wchar_t>(); }
1090#endif
1091
1092#ifdef _GLIBCXX_USE_CHAR8_T
1093 inline std::u8string
1094 path::u8string() const { return string<char8_t>(); }
1095#else
1096 inline std::string
1097 path::u8string() const
1098 {
1099#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1100 std::string __str;
1101 // convert from native wide encoding (assumed to be UTF-16) to UTF-8
1102 std::codecvt_utf8_utf16<value_type> __cvt;
1103 const value_type* __first = _M_pathname.data();
1104 const value_type* __last = __first + _M_pathname.size();
1105 if (__str_codecvt_out_all(__first, __last, __str, __cvt))
1106 return __str;
1107 __detail::__throw_conversion_error();
1108#else
1109 return _M_pathname;
1110#endif
1111 }
1112#endif // _GLIBCXX_USE_CHAR8_T
1113
1114 inline std::u16string
1115 path::u16string() const { return string<char16_t>(); }
1116
1117 inline std::u32string
1118 path::u32string() const { return string<char32_t>(); }
1119
1120 template<typename _CharT, typename _Traits, typename _Allocator>
1121 inline std::basic_string<_CharT, _Traits, _Allocator>
1122 path::generic_string(const _Allocator& __a) const
1123 {
1124#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1125 const value_type __slash = L'/';
1126#else
1127 const value_type __slash = '/';
1128#endif
1129 using _Alloc2 = typename allocator_traits<_Allocator>::template
1130 rebind_alloc<value_type>;
1131 basic_string<value_type, char_traits<value_type>, _Alloc2> __str(__a);
1132
1133 if (_M_type() == _Type::_Root_dir)
1134 __str.assign(1, __slash);
1135 else
1136 {
1137 __str.reserve(_M_pathname.size());
1138 bool __add_slash = false;
1139 for (auto& __elem : *this)
1140 {
1141#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1142 if (__elem._M_type() == _Type::_Root_dir)
1143 {
1144 __str += __slash;
1145 continue;
1146 }
1147#endif
1148 if (__add_slash)
1149 __str += __slash;
1150 __str += basic_string_view<value_type>(__elem._M_pathname);
1151 __add_slash = __elem._M_type() == _Type::_Filename;
1152 }
1153 }
1154
1155 if constexpr (is_same_v<_CharT, value_type>)
1156 return __str;
1157 else
1158 return _S_str_convert<_CharT, _Traits>(__str, __a);
1159 }
1160
1161 inline std::string
1162 path::generic_string() const
1163 { return generic_string<char>(); }
1164
1165#if _GLIBCXX_USE_WCHAR_T
1166 inline std::wstring
1167 path::generic_wstring() const
1168 { return generic_string<wchar_t>(); }
1169#endif
1170
1171#ifdef _GLIBCXX_USE_CHAR8_T
1172 inline std::u8string
1173 path::generic_u8string() const
1174 { return generic_string<char8_t>(); }
1175#else
1176 inline std::string
1177 path::generic_u8string() const
1178 { return generic_string(); }
1179#endif
1180
1181 inline std::u16string
1182 path::generic_u16string() const
1183 { return generic_string<char16_t>(); }
1184
1185 inline std::u32string
1186 path::generic_u32string() const
1187 { return generic_string<char32_t>(); }
1188
1189 inline int
1190 path::compare(const string_type& __s) const noexcept
1191 { return compare(s: basic_string_view<value_type>(__s)); }
1192
1193 inline int
1194 path::compare(const value_type* __s) const noexcept
1195 { return compare(s: basic_string_view<value_type>(__s)); }
1196
1197 inline path
1198 path::filename() const
1199 {
1200 if (empty())
1201 return {};
1202 else if (_M_type() == _Type::_Filename)
1203 return *this;
1204 else if (_M_type() == _Type::_Multi)
1205 {
1206 if (_M_pathname.back() == preferred_separator)
1207 return {};
1208 auto __last = --end();
1209 if (__last->_M_type() == _Type::_Filename)
1210 return *__last;
1211 }
1212 return {};
1213 }
1214
1215 inline path
1216 path::stem() const
1217 {
1218 auto ext = _M_find_extension();
1219 if (ext.first && ext.second != 0)
1220 return path{ext.first->substr(pos: 0, n: ext.second)};
1221 return {};
1222 }
1223
1224 inline path
1225 path::extension() const
1226 {
1227 auto ext = _M_find_extension();
1228 if (ext.first && ext.second != string_type::npos)
1229 return path{ext.first->substr(pos: ext.second)};
1230 return {};
1231 }
1232
1233 inline bool
1234 path::has_stem() const noexcept
1235 {
1236 auto ext = _M_find_extension();
1237 return ext.first && ext.second != 0;
1238 }
1239
1240 inline bool
1241 path::has_extension() const noexcept
1242 {
1243 auto ext = _M_find_extension();
1244 return ext.first && ext.second != string_type::npos;
1245 }
1246
1247 inline bool
1248 path::is_absolute() const noexcept
1249 {
1250#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
1251 return has_root_name() && has_root_directory();
1252#else
1253 return has_root_directory();
1254#endif
1255 }
1256
1257 inline path::iterator
1258 path::begin() const
1259 {
1260 if (_M_type() == _Type::_Multi)
1261 return iterator(this, _M_cmpts.begin());
1262 return iterator(this, empty());
1263 }
1264
1265 inline path::iterator
1266 path::end() const
1267 {
1268 if (_M_type() == _Type::_Multi)
1269 return iterator(this, _M_cmpts.end());
1270 return iterator(this, true);
1271 }
1272
1273 inline path::iterator&
1274 path::iterator::operator++()
1275 {
1276 __glibcxx_assert(_M_path != nullptr);
1277 if (_M_path->_M_type() == _Type::_Multi)
1278 {
1279 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.end());
1280 ++_M_cur;
1281 }
1282 else
1283 {
1284 __glibcxx_assert(!_M_at_end);
1285 _M_at_end = true;
1286 }
1287 return *this;
1288 }
1289
1290 inline path::iterator&
1291 path::iterator::operator--()
1292 {
1293 __glibcxx_assert(_M_path != nullptr);
1294 if (_M_path->_M_type() == _Type::_Multi)
1295 {
1296 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.begin());
1297 --_M_cur;
1298 }
1299 else
1300 {
1301 __glibcxx_assert(_M_at_end);
1302 _M_at_end = false;
1303 }
1304 return *this;
1305 }
1306
1307 inline path::iterator::reference
1308 path::iterator::operator*() const
1309 {
1310 __glibcxx_assert(_M_path != nullptr);
1311 if (_M_path->_M_type() == _Type::_Multi)
1312 {
1313 __glibcxx_assert(_M_cur != _M_path->_M_cmpts.end());
1314 return *_M_cur;
1315 }
1316 return *_M_path;
1317 }
1318
1319 inline bool
1320 path::iterator::_M_equals(iterator __rhs) const
1321 {
1322 if (_M_path != __rhs._M_path)
1323 return false;
1324 if (_M_path == nullptr)
1325 return true;
1326 if (_M_path->_M_type() == path::_Type::_Multi)
1327 return _M_cur == __rhs._M_cur;
1328 return _M_at_end == __rhs._M_at_end;
1329 }
1330
1331 // Define this now that path and path::iterator are complete.
1332 // It needs to consider the string_view(Range&&) constructor during
1333 // overload resolution, which depends on whether range<path> is satisfied,
1334 // which depends on whether path::iterator is complete.
1335 inline int
1336 path::_S_compare(const path& __lhs, const path& __rhs) noexcept
1337 { return __lhs.compare(p: __rhs); }
1338
1339 /// @} group filesystem
1340_GLIBCXX_END_NAMESPACE_CXX11
1341} // namespace filesystem
1342
1343/// @cond undocumented
1344
1345inline ptrdiff_t
1346distance(filesystem::path::iterator __first, filesystem::path::iterator __last)
1347{ return __path_iter_distance(__first, __last); }
1348
1349template<typename _Distance>
1350 void
1351 advance(filesystem::path::iterator& __i, _Distance __n)
1352 { __path_iter_advance(__i, n: static_cast<ptrdiff_t>(__n)); }
1353
1354extern template class __shared_ptr<const filesystem::filesystem_error::_Impl>;
1355
1356/// @endcond
1357
1358// _GLIBCXX_RESOLVE_LIB_DEFECTS
1359// 3657. std::hash<std::filesystem::path> is not enabled
1360template<>
1361 struct hash<filesystem::path>
1362 {
1363 size_t
1364 operator()(const filesystem::path& __p) const noexcept
1365 { return filesystem::hash_value(__p); }
1366 };
1367
1368_GLIBCXX_END_NAMESPACE_VERSION
1369} // namespace std
1370
1371#endif // C++17
1372
1373#endif // _GLIBCXX_FS_PATH_H
1374

source code of include/c++/11/bits/fs_path.h