libstdc++
debug/forward_list
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1// <forward_list> -*- C++ -*-
2
3// Copyright (C) 2010-2022 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 debug/forward_list
26 * This file is a GNU debug extension to the Standard C++ Library.
27 */
28
29#ifndef _GLIBCXX_DEBUG_FORWARD_LIST
30#define _GLIBCXX_DEBUG_FORWARD_LIST 1
31
32#pragma GCC system_header
33
34#include <bits/c++config.h>
35namespace std _GLIBCXX_VISIBILITY(default) { namespace __debug {
36 template<typename _Tp, typename _Allocator> class forward_list;
37} } // namespace std::__debug
38
39#include <forward_list>
40#include <debug/safe_sequence.h>
41#include <debug/safe_container.h>
42#include <debug/safe_iterator.h>
43
44// Special validity check for forward_list ranges.
45#define __glibcxx_check_valid_fl_range(_First,_Last,_Dist) \
46_GLIBCXX_DEBUG_VERIFY(_First._M_valid_range(_Last, _Dist, false), \
47 _M_message(__gnu_debug::__msg_valid_range) \
48 ._M_iterator(_First, #_First) \
49 ._M_iterator(_Last, #_Last))
50
51namespace __gnu_debug
52{
53 /// Special iterators swap and invalidation for forward_list because of the
54 /// before_begin iterator.
55 template<typename _SafeSequence>
56 class _Safe_forward_list
57 : public _Safe_sequence<_SafeSequence>
58 {
59 _SafeSequence&
60 _M_this() noexcept
61 { return *static_cast<_SafeSequence*>(this); }
62
63 static void
64 _M_swap_aux(_Safe_sequence_base& __lhs,
65 _Safe_iterator_base*& __lhs_iterators,
66 _Safe_sequence_base& __rhs,
67 _Safe_iterator_base*& __rhs_iterators);
68
69 void _M_swap_single(_Safe_sequence_base&) noexcept;
70
71 protected:
72 void
73 _M_invalidate_all()
74 {
75 using _Base_const_iterator = __decltype(_M_this()._M_base().cend());
76 this->_M_invalidate_if([this](_Base_const_iterator __it)
77 {
78 return __it != _M_this()._M_base().cbefore_begin()
79 && __it != _M_this()._M_base().cend(); });
80 }
81
82 void _M_swap(_Safe_sequence_base&) noexcept;
83 };
84
85 template<typename _SafeSequence>
86 void
87 _Safe_forward_list<_SafeSequence>::
88 _M_swap_aux(_Safe_sequence_base& __lhs,
89 _Safe_iterator_base*& __lhs_iterators,
90 _Safe_sequence_base& __rhs,
91 _Safe_iterator_base*& __rhs_iterators)
92 {
93 using const_iterator = typename _SafeSequence::const_iterator;
94 _Safe_iterator_base* __bbegin_its = 0;
95 _Safe_iterator_base* __last_bbegin = 0;
96 _SafeSequence& __rseq = static_cast<_SafeSequence&>(__rhs);
97
98 for (_Safe_iterator_base* __iter = __lhs_iterators; __iter;)
99 {
100 // Even iterator is cast to const_iterator, not a problem.
101 _Safe_iterator_base* __victim_base = __iter;
102 const_iterator* __victim =
103 static_cast<const_iterator*>(__victim_base);
104 __iter = __iter->_M_next;
105 if (__victim->base() == __rseq._M_base().cbefore_begin())
106 {
107 __victim->_M_unlink();
108 if (__lhs_iterators == __victim_base)
109 __lhs_iterators = __victim_base->_M_next;
110 if (__bbegin_its)
111 {
112 __victim_base->_M_next = __bbegin_its;
113 __bbegin_its->_M_prior = __victim_base;
114 }
115 else
116 __last_bbegin = __victim_base;
117 __bbegin_its = __victim_base;
118 }
119 else
120 __victim_base->_M_sequence = std::__addressof(__lhs);
121 }
122
123 if (__bbegin_its)
124 {
125 if (__rhs_iterators)
126 {
127 __rhs_iterators->_M_prior = __last_bbegin;
128 __last_bbegin->_M_next = __rhs_iterators;
129 }
130 __rhs_iterators = __bbegin_its;
131 }
132 }
133
134 template<typename _SafeSequence>
135 void
136 _Safe_forward_list<_SafeSequence>::
137 _M_swap_single(_Safe_sequence_base& __other) noexcept
138 {
139 std::swap(_M_this()._M_iterators, __other._M_iterators);
140 std::swap(_M_this()._M_const_iterators, __other._M_const_iterators);
141 // Useless, always 1 on forward_list
142 //std::swap(_M_this()_M_version, __other._M_version);
143 _Safe_iterator_base* __this_its = _M_this()._M_iterators;
144 _M_swap_aux(__other, __other._M_iterators,
145 _M_this(), _M_this()._M_iterators);
146 _Safe_iterator_base* __this_const_its = _M_this()._M_const_iterators;
147 _M_swap_aux(__other, __other._M_const_iterators,
148 _M_this(), _M_this()._M_const_iterators);
149 _M_swap_aux(_M_this(), __this_its,
150 __other, __other._M_iterators);
151 _M_swap_aux(_M_this(), __this_const_its,
152 __other, __other._M_const_iterators);
153 }
154
155 /* Special forward_list _M_swap version that does not swap the
156 * before-begin ownership.*/
157 template<typename _SafeSequence>
158 void
159 _Safe_forward_list<_SafeSequence>::
160 _M_swap(_Safe_sequence_base& __other) noexcept
161 {
162 // We need to lock both sequences to swap
163 using namespace __gnu_cxx;
164 __mutex *__this_mutex = &_M_this()._M_get_mutex();
165 __mutex *__other_mutex =
166 &static_cast<_SafeSequence&>(__other)._M_get_mutex();
167 if (__this_mutex == __other_mutex)
168 {
169 __scoped_lock __lock(*__this_mutex);
170 _M_swap_single(__other);
171 }
172 else
173 {
174 __scoped_lock __l1(__this_mutex < __other_mutex
175 ? *__this_mutex : *__other_mutex);
176 __scoped_lock __l2(__this_mutex < __other_mutex
177 ? *__other_mutex : *__this_mutex);
178 _M_swap_single(__other);
179 }
180 }
181}
182
183namespace std _GLIBCXX_VISIBILITY(default)
184{
185namespace __debug
186{
187 /// Class std::forward_list with safety/checking/debug instrumentation.
188 template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
189 class forward_list
190 : public __gnu_debug::_Safe_container<
191 forward_list<_Tp, _Alloc>, _Alloc, __gnu_debug::_Safe_forward_list>,
192 public _GLIBCXX_STD_C::forward_list<_Tp, _Alloc>
193 {
194 typedef _GLIBCXX_STD_C::forward_list<_Tp, _Alloc> _Base;
195 typedef __gnu_debug::_Safe_container<
196 forward_list, _Alloc, __gnu_debug::_Safe_forward_list> _Safe;
197
198 typedef typename _Base::iterator _Base_iterator;
199 typedef typename _Base::const_iterator _Base_const_iterator;
200
201 template<typename _ItT, typename _SeqT, typename _CatT>
202 friend class ::__gnu_debug::_Safe_iterator;
203
204 // Reference wrapper for base class. See PR libstdc++/90102.
205 struct _Base_ref
206 {
207 _Base_ref(const _Base& __r) : _M_ref(__r) { }
208
209 const _Base& _M_ref;
210 };
211
212 public:
213 typedef typename _Base::reference reference;
214 typedef typename _Base::const_reference const_reference;
215
216 typedef __gnu_debug::_Safe_iterator<
217 _Base_iterator, forward_list> iterator;
218 typedef __gnu_debug::_Safe_iterator<
219 _Base_const_iterator, forward_list> const_iterator;
220
221 typedef typename _Base::size_type size_type;
222 typedef typename _Base::difference_type difference_type;
223
224 typedef _Tp value_type;
225 typedef typename _Base::allocator_type allocator_type;
226 typedef typename _Base::pointer pointer;
227 typedef typename _Base::const_pointer const_pointer;
228
229 // 23.2.3.1 construct/copy/destroy:
230
231 forward_list() = default;
232
233 explicit
234 forward_list(const allocator_type& __al) noexcept
235 : _Base(__al) { }
236
237 forward_list(const forward_list& __list, const allocator_type& __al)
238 : _Base(__list, __al)
239 { }
240
241 forward_list(forward_list&& __list, const allocator_type& __al)
242 noexcept(
243 std::is_nothrow_constructible<_Base,
244 _Base, const allocator_type&>::value )
245 : _Safe(std::move(__list), __al),
246 _Base(std::move(__list), __al)
247 { }
248
249 explicit
250 forward_list(size_type __n, const allocator_type& __al = allocator_type())
251 : _Base(__n, __al)
252 { }
253
254 forward_list(size_type __n, const __type_identity_t<_Tp>& __value,
255 const allocator_type& __al = allocator_type())
256 : _Base(__n, __value, __al)
257 { }
258
259 template<typename _InputIterator,
260 typename = std::_RequireInputIter<_InputIterator>>
261 forward_list(_InputIterator __first, _InputIterator __last,
262 const allocator_type& __al = allocator_type())
263 : _Base(__gnu_debug::__base(
264 __glibcxx_check_valid_constructor_range(__first, __last)),
265 __gnu_debug::__base(__last), __al)
266 { }
267
268 forward_list(const forward_list&) = default;
269
270 forward_list(forward_list&&) = default;
271
272 forward_list(std::initializer_list<_Tp> __il,
273 const allocator_type& __al = allocator_type())
274 : _Base(__il, __al)
275 { }
276
277 ~forward_list() = default;
278
279 forward_list(_Base_ref __x) : _Base(__x._M_ref) { }
280
281 forward_list&
282 operator=(const forward_list&) = default;
283
284 forward_list&
285 operator=(forward_list&&) = default;
286
287 forward_list&
288 operator=(std::initializer_list<_Tp> __il)
289 {
290 _Base::operator=(__il);
291 this->_M_invalidate_all();
292 return *this;
293 }
294
295 template<typename _InputIterator,
296 typename = std::_RequireInputIter<_InputIterator>>
297 void
298 assign(_InputIterator __first, _InputIterator __last)
299 {
300 typename __gnu_debug::_Distance_traits<_InputIterator>::__type __dist;
301 __glibcxx_check_valid_range2(__first, __last, __dist);
302
303 if (__dist.second >= __gnu_debug::__dp_sign)
304 _Base::assign(__gnu_debug::__unsafe(__first),
305 __gnu_debug::__unsafe(__last));
306 else
307 _Base::assign(__first, __last);
308
309 this->_M_invalidate_all();
310 }
311
312 void
313 assign(size_type __n, const _Tp& __val)
314 {
315 _Base::assign(__n, __val);
316 this->_M_invalidate_all();
317 }
318
319 void
320 assign(std::initializer_list<_Tp> __il)
321 {
322 _Base::assign(__il);
323 this->_M_invalidate_all();
324 }
325
326 using _Base::get_allocator;
327
328 // iterators:
329
330 [[__nodiscard__]]
331 iterator
332 before_begin() noexcept
333 { return { _Base::before_begin(), this }; }
334
335 [[__nodiscard__]]
336 const_iterator
337 before_begin() const noexcept
338 { return { _Base::before_begin(), this }; }
339
340 [[__nodiscard__]]
341 iterator
342 begin() noexcept
343 { return { _Base::begin(), this }; }
344
345 [[__nodiscard__]]
346 const_iterator
347 begin() const noexcept
348 { return { _Base::begin(), this }; }
349
350 [[__nodiscard__]]
351 iterator
352 end() noexcept
353 { return { _Base::end(), this }; }
354
355 [[__nodiscard__]]
356 const_iterator
357 end() const noexcept
358 { return { _Base::end(), this }; }
359
360 [[__nodiscard__]]
361 const_iterator
362 cbegin() const noexcept
363 { return { _Base::cbegin(), this }; }
364
365 [[__nodiscard__]]
366 const_iterator
367 cbefore_begin() const noexcept
368 { return { _Base::cbefore_begin(), this }; }
369
370 [[__nodiscard__]]
371 const_iterator
372 cend() const noexcept
373 { return { _Base::cend(), this }; }
374
375 using _Base::empty;
376 using _Base::max_size;
377
378 // element access:
379
380 [[__nodiscard__]]
381 reference
382 front()
383 {
384 __glibcxx_check_nonempty();
385 return _Base::front();
386 }
387
388 [[__nodiscard__]]
389 const_reference
390 front() const
391 {
392 __glibcxx_check_nonempty();
393 return _Base::front();
394 }
395
396 // modifiers:
397
398 using _Base::emplace_front;
399 using _Base::push_front;
400
401 void
402 pop_front()
403 {
404 __glibcxx_check_nonempty();
405 this->_M_invalidate_if([this](_Base_const_iterator __it)
406 { return __it == this->_M_base().cbegin(); });
407 _Base::pop_front();
408 }
409
410 template<typename... _Args>
411 iterator
412 emplace_after(const_iterator __pos, _Args&&... __args)
413 {
414 __glibcxx_check_insert_after(__pos);
415 return { _Base::emplace_after(__pos.base(),
416 std::forward<_Args>(__args)...),
417 this };
418 }
419
420 iterator
421 insert_after(const_iterator __pos, const _Tp& __val)
422 {
423 __glibcxx_check_insert_after(__pos);
424 return { _Base::insert_after(__pos.base(), __val), this };
425 }
426
427 iterator
428 insert_after(const_iterator __pos, _Tp&& __val)
429 {
430 __glibcxx_check_insert_after(__pos);
431 return { _Base::insert_after(__pos.base(), std::move(__val)), this };
432 }
433
434 iterator
435 insert_after(const_iterator __pos, size_type __n, const _Tp& __val)
436 {
437 __glibcxx_check_insert_after(__pos);
438 return { _Base::insert_after(__pos.base(), __n, __val), this };
439 }
440
441 template<typename _InputIterator,
442 typename = std::_RequireInputIter<_InputIterator>>
443 iterator
444 insert_after(const_iterator __pos,
445 _InputIterator __first, _InputIterator __last)
446 {
447 typename __gnu_debug::_Distance_traits<_InputIterator>::__type __dist;
448 __glibcxx_check_insert_range_after(__pos, __first, __last, __dist);
449
450 if (__dist.second >= __gnu_debug::__dp_sign)
451 return
452 {
453 _Base::insert_after(__pos.base(),
454 __gnu_debug::__unsafe(__first),
455 __gnu_debug::__unsafe(__last)),
456 this
457 };
458 else
459 return { _Base::insert_after(__pos.base(), __first, __last), this };
460 }
461
462 iterator
463 insert_after(const_iterator __pos, std::initializer_list<_Tp> __il)
464 {
465 __glibcxx_check_insert_after(__pos);
466 return { _Base::insert_after(__pos.base(), __il), this };
467 }
468
469 iterator
470 erase_after(const_iterator __pos)
471 {
472 __glibcxx_check_erase_after(__pos);
473
474 _Base_const_iterator __next = std::next(__pos.base());
475 this->_M_invalidate_if([__next](_Base_const_iterator __it)
476 { return __it == __next; });
477 return { _Base::erase_after(__pos.base()), this };
478 }
479
480 iterator
481 erase_after(const_iterator __pos, const_iterator __last)
482 {
483 __glibcxx_check_erase_range_after(__pos, __last);
484 for (_Base_const_iterator __victim = std::next(__pos.base());
485 __victim != __last.base(); ++__victim)
486 {
487 _GLIBCXX_DEBUG_VERIFY(__victim != _Base::cend(),
488 _M_message(__gnu_debug::__msg_valid_range2)
489 ._M_sequence(*this, "this")
490 ._M_iterator(__pos, "pos")
491 ._M_iterator(__last, "last"));
492 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
493 { return __it == __victim; });
494 }
495
496 return { _Base::erase_after(__pos.base(), __last.base()), this };
497 }
498
499 void
500 swap(forward_list& __list)
501 noexcept( noexcept(declval<_Base&>().swap(__list)) )
502 {
503 _Safe::_M_swap(__list);
504 _Base::swap(__list);
505 }
506
507 void
508 resize(size_type __sz)
509 {
510 this->_M_detach_singular();
511
512 // if __sz < size(), invalidate all iterators in [begin+__sz, end()
513 _Base_iterator __victim = _Base::begin();
514 _Base_iterator __end = _Base::end();
515 for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
516 ++__victim;
517
518 for (; __victim != __end; ++__victim)
519 {
520 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
521 { return __it == __victim; });
522 }
523
524 __try
525 {
526 _Base::resize(__sz);
527 }
528 __catch(...)
529 {
530 this->_M_revalidate_singular();
531 __throw_exception_again;
532 }
533 }
534
535 void
536 resize(size_type __sz, const value_type& __val)
537 {
538 this->_M_detach_singular();
539
540 // if __sz < size(), invalidate all iterators in [begin+__sz, end())
541 _Base_iterator __victim = _Base::begin();
542 _Base_iterator __end = _Base::end();
543 for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
544 ++__victim;
545
546 for (; __victim != __end; ++__victim)
547 {
548 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
549 { return __it == __victim; });
550 }
551
552 __try
553 {
554 _Base::resize(__sz, __val);
555 }
556 __catch(...)
557 {
558 this->_M_revalidate_singular();
559 __throw_exception_again;
560 }
561 }
562
563 void
564 clear() noexcept
565 {
566 _Base::clear();
567 this->_M_invalidate_all();
568 }
569
570 // 23.2.3.5 forward_list operations:
571 void
572 splice_after(const_iterator __pos, forward_list&& __list)
573 {
574 __glibcxx_check_insert_after(__pos);
575 _GLIBCXX_DEBUG_VERIFY(std::__addressof(__list) != this,
576 _M_message(__gnu_debug::__msg_self_splice)
577 ._M_sequence(*this, "this"));
578 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
579 _M_message(__gnu_debug::__msg_splice_alloc)
580 ._M_sequence(*this)
581 ._M_sequence(__list, "__list"));
582 this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
583 {
584 return __it != __list._M_base().cbefore_begin()
585 && __it != __list._M_base().end();
586 });
587 _Base::splice_after(__pos.base(), std::move(__list));
588 }
589
590 void
591 splice_after(const_iterator __pos, forward_list& __list)
592 { splice_after(__pos, std::move(__list)); }
593
594 void
595 splice_after(const_iterator __pos, forward_list&& __list,
596 const_iterator __i)
597 {
598 __glibcxx_check_insert_after(__pos);
599 _GLIBCXX_DEBUG_VERIFY(__i._M_before_dereferenceable(),
600 _M_message(__gnu_debug::__msg_splice_bad)
601 ._M_iterator(__i, "__i"));
602 _GLIBCXX_DEBUG_VERIFY(__i._M_attached_to(std::__addressof(__list)),
603 _M_message(__gnu_debug::__msg_splice_other)
604 ._M_iterator(__i, "__i")
605 ._M_sequence(__list, "__list"));
606 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
607 _M_message(__gnu_debug::__msg_splice_alloc)
608 ._M_sequence(*this)
609 ._M_sequence(__list, "__list"));
610
611 // _GLIBCXX_RESOLVE_LIB_DEFECTS
612 // 250. splicing invalidates iterators
613 _Base_const_iterator __next = std::next(__i.base());
614 this->_M_transfer_from_if(__list, [__next](_Base_const_iterator __it)
615 { return __it == __next; });
616 _Base::splice_after(__pos.base(), std::move(__list), __i.base());
617 }
618
619 void
620 splice_after(const_iterator __pos, forward_list& __list,
621 const_iterator __i)
622 { splice_after(__pos, std::move(__list), __i); }
623
624 void
625 splice_after(const_iterator __pos, forward_list&& __list,
626 const_iterator __before, const_iterator __last)
627 {
628 typename __gnu_debug::_Distance_traits<const_iterator>::__type __dist;
629 auto __listptr = std::__addressof(__list);
630 __glibcxx_check_insert_after(__pos);
631 __glibcxx_check_valid_fl_range(__before, __last, __dist);
632 _GLIBCXX_DEBUG_VERIFY(__before._M_attached_to(__listptr),
633 _M_message(__gnu_debug::__msg_splice_other)
634 ._M_sequence(__list, "list")
635 ._M_iterator(__before, "before"));
636 _GLIBCXX_DEBUG_VERIFY(__before._M_dereferenceable()
637 || __before._M_is_before_begin(),
638 _M_message(__gnu_debug::__msg_valid_range2)
639 ._M_sequence(__list, "list")
640 ._M_iterator(__before, "before")
641 ._M_iterator(__last, "last"));
642 _GLIBCXX_DEBUG_VERIFY(__before != __last,
643 _M_message(__gnu_debug::__msg_valid_range2)
644 ._M_sequence(__list, "list")
645 ._M_iterator(__before, "before")
646 ._M_iterator(__last, "last"));
647 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
648 _M_message(__gnu_debug::__msg_splice_alloc)
649 ._M_sequence(*this)
650 ._M_sequence(__list, "__list"));
651
652 for (_Base_const_iterator __tmp = std::next(__before.base());
653 __tmp != __last.base(); ++__tmp)
654 {
655 _GLIBCXX_DEBUG_VERIFY(__tmp != __list._M_base().end(),
656 _M_message(__gnu_debug::__msg_valid_range2)
657 ._M_sequence(__list, "list")
658 ._M_iterator(__before, "before")
659 ._M_iterator(__last, "last"));
660 _GLIBCXX_DEBUG_VERIFY(__listptr != this || __tmp != __pos.base(),
661 _M_message(__gnu_debug::__msg_splice_overlap)
662 ._M_iterator(__tmp, "position")
663 ._M_iterator(__before, "before")
664 ._M_iterator(__last, "last"));
665 // _GLIBCXX_RESOLVE_LIB_DEFECTS
666 // 250. splicing invalidates iterators
667 this->_M_transfer_from_if(__list, [__tmp](_Base_const_iterator __it)
668 { return __it == __tmp; });
669 }
670
671 _Base::splice_after(__pos.base(), std::move(__list),
672 __before.base(), __last.base());
673 }
674
675 void
676 splice_after(const_iterator __pos, forward_list& __list,
677 const_iterator __before, const_iterator __last)
678 { splice_after(__pos, std::move(__list), __before, __last); }
679
680 private:
681#if __cplusplus > 201703L
682 using __remove_return_type = size_type;
683# define _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG \
684 __attribute__((__abi_tag__("__cxx20")))
685# define _GLIBCXX20_ONLY(__expr) __expr
686#else
687 using __remove_return_type = void;
688# define _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
689# define _GLIBCXX20_ONLY(__expr)
690#endif
691
692 public:
693 _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
694 __remove_return_type
695 remove(const _Tp& __val)
696 {
697 if (!this->_M_iterators && !this->_M_const_iterators)
698 return _Base::remove(__val);
699
700 size_type __removed __attribute__((__unused__)) = 0;
701 _Base __to_destroy(get_allocator());
702 _Base_const_iterator __x = _Base::cbefore_begin();
703 _Base_const_iterator __old = __x++;
704 while (__x != _Base::cend())
705 {
706 if (*__x == __val)
707 {
708 _Base_const_iterator __next = std::next(__old);
709 this->_M_invalidate_if([__next](_Base_const_iterator __it)
710 { return __it == __next; });
711 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
712 *this, __old);
713 __x = __old;
714 _GLIBCXX20_ONLY( __removed++ );
715 }
716
717 __old = __x++;
718 }
719
720 return _GLIBCXX20_ONLY( __removed );
721 }
722
723 template<typename _Pred>
724 __remove_return_type
725 remove_if(_Pred __pred)
726 {
727 if (!this->_M_iterators && !this->_M_const_iterators)
728 return _Base::remove_if(__pred);
729
730 size_type __removed __attribute__((__unused__)) = 0;
731 _Base __to_destroy(get_allocator());
732 _Base_iterator __x = _Base::before_begin();
733 _Base_iterator __old = __x++;
734 while (__x != _Base::end())
735 {
736 if (__pred(*__x))
737 {
738 this->_M_invalidate_if([__x](_Base_const_iterator __it)
739 { return __it == __x; });
740 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
741 *this, __old);
742 __x = __old;
743 _GLIBCXX20_ONLY( __removed++ );
744 }
745
746 __old = __x++;
747 }
748
749 return _GLIBCXX20_ONLY( __removed );
750 }
751
752 _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
753 __remove_return_type
754 unique()
755 { return unique(std::equal_to<_Tp>()); }
756
757 template<typename _BinPred>
758 __remove_return_type
759 unique(_BinPred __binary_pred)
760 {
761 if (!this->_M_iterators && !this->_M_const_iterators)
762 return _Base::unique(__binary_pred);
763
764 _Base_const_iterator __first = _Base::cbegin();
765 _Base_const_iterator __last = _Base::cend();
766 if (__first == __last)
767 return _GLIBCXX20_ONLY(0);
768
769 size_type __removed __attribute__((__unused__)) = 0;
770 _Base __to_destroy(get_allocator());
771 _Base_const_iterator __next = std::next(__first);
772 while (__next != __last)
773 {
774 if (__binary_pred(*__first, *__next))
775 {
776 this->_M_invalidate_if([__next](_Base_const_iterator __it)
777 { return __it == __next; });
778 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
779 *this, __first);
780 __next = __first;
781 _GLIBCXX20_ONLY( __removed++ );
782 }
783
784 __first = __next++;
785 }
786
787 return _GLIBCXX20_ONLY( __removed );
788 }
789
790#undef _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
791#undef _GLIBCXX20_ONLY
792
793 void
794 merge(forward_list&& __list)
795 {
796 if (this != std::__addressof(__list))
797 {
798 __glibcxx_check_sorted(_Base::begin(), _Base::end());
799 __glibcxx_check_sorted(__list._M_base().begin(),
800 __list._M_base().end());
801 this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
802 {
803 return __it != __list._M_base().cbefore_begin()
804 && __it != __list._M_base().cend();
805 });
806 _Base::merge(std::move(__list));
807 }
808 }
809
810 void
811 merge(forward_list& __list)
812 { merge(std::move(__list)); }
813
814 template<typename _Comp>
815 void
816 merge(forward_list&& __list, _Comp __comp)
817 {
818 if (this != std::__addressof(__list))
819 {
820 __glibcxx_check_sorted_pred(_Base::begin(), _Base::end(), __comp);
821 __glibcxx_check_sorted_pred(__list._M_base().begin(),
822 __list._M_base().end(), __comp);
823 this->_M_transfer_from_if(__list,
824 [&__list](_Base_const_iterator __it)
825 {
826 return __it != __list._M_base().cbefore_begin()
827 && __it != __list._M_base().cend();
828 });
829 _Base::merge(std::move(__list), __comp);
830 }
831 }
832
833 template<typename _Comp>
834 void
835 merge(forward_list& __list, _Comp __comp)
836 { merge(std::move(__list), __comp); }
837
838 using _Base::sort;
839 using _Base::reverse;
840
841 _Base&
842 _M_base() noexcept { return *this; }
843
844 const _Base&
845 _M_base() const noexcept { return *this; }
846 };
847
848#if __cpp_deduction_guides >= 201606
849 template<typename _InputIterator, typename _ValT
850 = typename iterator_traits<_InputIterator>::value_type,
851 typename _Allocator = allocator<_ValT>,
852 typename = _RequireInputIter<_InputIterator>,
853 typename = _RequireAllocator<_Allocator>>
854 forward_list(_InputIterator, _InputIterator, _Allocator = _Allocator())
855 -> forward_list<_ValT, _Allocator>;
856
857 template<typename _Tp, typename _Allocator = allocator<_Tp>,
858 typename = _RequireAllocator<_Allocator>>
859 forward_list(size_t, _Tp, _Allocator = _Allocator())
860 -> forward_list<_Tp, _Allocator>;
861#endif
862
863 template<typename _Tp, typename _Alloc>
864 bool
865 operator==(const forward_list<_Tp, _Alloc>& __lx,
866 const forward_list<_Tp, _Alloc>& __ly)
867 { return __lx._M_base() == __ly._M_base(); }
868
869#if __cpp_lib_three_way_comparison
870 template<typename _Tp, typename _Alloc>
871 constexpr __detail::__synth3way_t<_Tp>
872 operator<=>(const forward_list<_Tp, _Alloc>& __x,
873 const forward_list<_Tp, _Alloc>& __y)
874 { return __x._M_base() <=> __y._M_base(); }
875#else
876 template<typename _Tp, typename _Alloc>
877 inline bool
878 operator<(const forward_list<_Tp, _Alloc>& __lx,
879 const forward_list<_Tp, _Alloc>& __ly)
880 { return __lx._M_base() < __ly._M_base(); }
881
882 template<typename _Tp, typename _Alloc>
883 inline bool
884 operator!=(const forward_list<_Tp, _Alloc>& __lx,
885 const forward_list<_Tp, _Alloc>& __ly)
886 { return !(__lx == __ly); }
887
888 /// Based on operator<
889 template<typename _Tp, typename _Alloc>
890 inline bool
891 operator>(const forward_list<_Tp, _Alloc>& __lx,
892 const forward_list<_Tp, _Alloc>& __ly)
893 { return (__ly < __lx); }
894
895 /// Based on operator<
896 template<typename _Tp, typename _Alloc>
897 inline bool
898 operator>=(const forward_list<_Tp, _Alloc>& __lx,
899 const forward_list<_Tp, _Alloc>& __ly)
900 { return !(__lx < __ly); }
901
902 /// Based on operator<
903 template<typename _Tp, typename _Alloc>
904 inline bool
905 operator<=(const forward_list<_Tp, _Alloc>& __lx,
906 const forward_list<_Tp, _Alloc>& __ly)
907 { return !(__ly < __lx); }
908#endif // three-way comparison
909
910 /// See std::forward_list::swap().
911 template<typename _Tp, typename _Alloc>
912 inline void
913 swap(forward_list<_Tp, _Alloc>& __lx, forward_list<_Tp, _Alloc>& __ly)
914 noexcept(noexcept(__lx.swap(__ly)))
915 { __lx.swap(__ly); }
916
917} // namespace __debug
918} // namespace std
919
920namespace __gnu_debug
921{
922 template<typename _Tp, typename _Alloc>
923 struct _BeforeBeginHelper<std::__debug::forward_list<_Tp, _Alloc> >
924 {
925 typedef std::__debug::forward_list<_Tp, _Alloc> _Sequence;
926
927 template<typename _Iterator>
928 static bool
929 _S_Is(const _Safe_iterator<_Iterator, _Sequence>& __it)
930 {
931 return
932 __it.base() == __it._M_get_sequence()->_M_base().before_begin();
933 }
934
935 template<typename _Iterator>
936 static bool
937 _S_Is_Beginnest(const _Safe_iterator<_Iterator, _Sequence>& __it)
938 { return _S_Is(__it); }
939 };
940
941 template<typename _Tp, typename _Alloc>
942 struct _Sequence_traits<std::__debug::forward_list<_Tp, _Alloc> >
943 {
944 typedef typename std::__debug::forward_list<_Tp, _Alloc>::iterator _It;
945
946 static typename _Distance_traits<_It>::__type
947 _S_size(const std::__debug::forward_list<_Tp, _Alloc>& __seq)
948 {
949 return __seq.empty()
950 ? std::make_pair(0, __dp_exact) : std::make_pair(1, __dp_sign);
951 }
952 };
953
954#ifndef _GLIBCXX_DEBUG_PEDANTIC
955 template<class _Tp, class _Alloc>
956 struct _Insert_range_from_self_is_safe<
957 std::__debug::forward_list<_Tp, _Alloc> >
958 { enum { __value = 1 }; };
959#endif
960}
961
962#endif