libstdc++
debug/forward_list
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1// <forward_list> -*- C++ -*-
2
3// Copyright (C) 2010-2021 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 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._M_safe()), __al),
246 _Base(std::move(__list._M_base()), __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 _M_base() = __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 iterator
331 before_begin() noexcept
332 { return { _Base::before_begin(), this }; }
333
334 const_iterator
335 before_begin() const noexcept
336 { return { _Base::before_begin(), this }; }
337
338 iterator
339 begin() noexcept
340 { return { _Base::begin(), this }; }
341
342 const_iterator
343 begin() const noexcept
344 { return { _Base::begin(), this }; }
345
346 iterator
347 end() noexcept
348 { return { _Base::end(), this }; }
349
350 const_iterator
351 end() const noexcept
352 { return { _Base::end(), this }; }
353
354 const_iterator
355 cbegin() const noexcept
356 { return { _Base::cbegin(), this }; }
357
358 const_iterator
359 cbefore_begin() const noexcept
360 { return { _Base::cbefore_begin(), this }; }
361
362 const_iterator
363 cend() const noexcept
364 { return { _Base::cend(), this }; }
365
366 using _Base::empty;
367 using _Base::max_size;
368
369 // element access:
370
371 reference
372 front()
373 {
374 __glibcxx_check_nonempty();
375 return _Base::front();
376 }
377
378 const_reference
379 front() const
380 {
381 __glibcxx_check_nonempty();
382 return _Base::front();
383 }
384
385 // modifiers:
386
387 using _Base::emplace_front;
388 using _Base::push_front;
389
390 void
391 pop_front()
392 {
393 __glibcxx_check_nonempty();
394 this->_M_invalidate_if([this](_Base_const_iterator __it)
395 { return __it == this->_M_base().cbegin(); });
396 _Base::pop_front();
397 }
398
399 template<typename... _Args>
400 iterator
401 emplace_after(const_iterator __pos, _Args&&... __args)
402 {
403 __glibcxx_check_insert_after(__pos);
404 return { _Base::emplace_after(__pos.base(),
405 std::forward<_Args>(__args)...),
406 this };
407 }
408
409 iterator
410 insert_after(const_iterator __pos, const _Tp& __val)
411 {
412 __glibcxx_check_insert_after(__pos);
413 return { _Base::insert_after(__pos.base(), __val), this };
414 }
415
416 iterator
417 insert_after(const_iterator __pos, _Tp&& __val)
418 {
419 __glibcxx_check_insert_after(__pos);
420 return { _Base::insert_after(__pos.base(), std::move(__val)), this };
421 }
422
423 iterator
424 insert_after(const_iterator __pos, size_type __n, const _Tp& __val)
425 {
426 __glibcxx_check_insert_after(__pos);
427 return { _Base::insert_after(__pos.base(), __n, __val), this };
428 }
429
430 template<typename _InputIterator,
431 typename = std::_RequireInputIter<_InputIterator>>
432 iterator
433 insert_after(const_iterator __pos,
434 _InputIterator __first, _InputIterator __last)
435 {
436 typename __gnu_debug::_Distance_traits<_InputIterator>::__type __dist;
437 __glibcxx_check_insert_range_after(__pos, __first, __last, __dist);
438
439 if (__dist.second >= __gnu_debug::__dp_sign)
440 return
441 {
442 _Base::insert_after(__pos.base(),
443 __gnu_debug::__unsafe(__first),
444 __gnu_debug::__unsafe(__last)),
445 this
446 };
447 else
448 return { _Base::insert_after(__pos.base(), __first, __last), this };
449 }
450
451 iterator
452 insert_after(const_iterator __pos, std::initializer_list<_Tp> __il)
453 {
454 __glibcxx_check_insert_after(__pos);
455 return { _Base::insert_after(__pos.base(), __il), this };
456 }
457
458 iterator
459 erase_after(const_iterator __pos)
460 {
461 __glibcxx_check_erase_after(__pos);
462
463 _Base_const_iterator __next = std::next(__pos.base());
464 this->_M_invalidate_if([__next](_Base_const_iterator __it)
465 { return __it == __next; });
466 return { _Base::erase_after(__pos.base()), this };
467 }
468
469 iterator
470 erase_after(const_iterator __pos, const_iterator __last)
471 {
472 __glibcxx_check_erase_range_after(__pos, __last);
473 for (_Base_const_iterator __victim = std::next(__pos.base());
474 __victim != __last.base(); ++__victim)
475 {
476 _GLIBCXX_DEBUG_VERIFY(__victim != _Base::cend(),
477 _M_message(__gnu_debug::__msg_valid_range2)
478 ._M_sequence(*this, "this")
479 ._M_iterator(__pos, "pos")
480 ._M_iterator(__last, "last"));
481 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
482 { return __it == __victim; });
483 }
484
485 return { _Base::erase_after(__pos.base(), __last.base()), this };
486 }
487
488 void
489 swap(forward_list& __list)
490 noexcept( noexcept(declval<_Base&>().swap(__list)) )
491 {
492 _Safe::_M_swap(__list);
493 _Base::swap(__list);
494 }
495
496 void
497 resize(size_type __sz)
498 {
499 this->_M_detach_singular();
500
501 // if __sz < size(), invalidate all iterators in [begin+__sz, end()
502 _Base_iterator __victim = _Base::begin();
503 _Base_iterator __end = _Base::end();
504 for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
505 ++__victim;
506
507 for (; __victim != __end; ++__victim)
508 {
509 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
510 { return __it == __victim; });
511 }
512
513 __try
514 {
515 _Base::resize(__sz);
516 }
517 __catch(...)
518 {
519 this->_M_revalidate_singular();
520 __throw_exception_again;
521 }
522 }
523
524 void
525 resize(size_type __sz, const value_type& __val)
526 {
527 this->_M_detach_singular();
528
529 // if __sz < size(), invalidate all iterators in [begin+__sz, end())
530 _Base_iterator __victim = _Base::begin();
531 _Base_iterator __end = _Base::end();
532 for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
533 ++__victim;
534
535 for (; __victim != __end; ++__victim)
536 {
537 this->_M_invalidate_if([__victim](_Base_const_iterator __it)
538 { return __it == __victim; });
539 }
540
541 __try
542 {
543 _Base::resize(__sz, __val);
544 }
545 __catch(...)
546 {
547 this->_M_revalidate_singular();
548 __throw_exception_again;
549 }
550 }
551
552 void
553 clear() noexcept
554 {
555 _Base::clear();
556 this->_M_invalidate_all();
557 }
558
559 // 23.2.3.5 forward_list operations:
560 void
561 splice_after(const_iterator __pos, forward_list&& __list)
562 {
563 __glibcxx_check_insert_after(__pos);
564 _GLIBCXX_DEBUG_VERIFY(std::__addressof(__list) != this,
565 _M_message(__gnu_debug::__msg_self_splice)
566 ._M_sequence(*this, "this"));
567 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
568 _M_message(__gnu_debug::__msg_splice_alloc)
569 ._M_sequence(*this)
570 ._M_sequence(__list, "__list"));
571 this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
572 {
573 return __it != __list._M_base().cbefore_begin()
574 && __it != __list._M_base().end();
575 });
576 _Base::splice_after(__pos.base(), std::move(__list._M_base()));
577 }
578
579 void
580 splice_after(const_iterator __pos, forward_list& __list)
581 { splice_after(__pos, std::move(__list)); }
582
583 void
584 splice_after(const_iterator __pos, forward_list&& __list,
585 const_iterator __i)
586 {
587 __glibcxx_check_insert_after(__pos);
588 _GLIBCXX_DEBUG_VERIFY(__i._M_before_dereferenceable(),
589 _M_message(__gnu_debug::__msg_splice_bad)
590 ._M_iterator(__i, "__i"));
591 _GLIBCXX_DEBUG_VERIFY(__i._M_attached_to(std::__addressof(__list)),
592 _M_message(__gnu_debug::__msg_splice_other)
593 ._M_iterator(__i, "__i")
594 ._M_sequence(__list, "__list"));
595 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
596 _M_message(__gnu_debug::__msg_splice_alloc)
597 ._M_sequence(*this)
598 ._M_sequence(__list, "__list"));
599
600 // _GLIBCXX_RESOLVE_LIB_DEFECTS
601 // 250. splicing invalidates iterators
602 _Base_const_iterator __next = std::next(__i.base());
603 this->_M_transfer_from_if(__list, [__next](_Base_const_iterator __it)
604 { return __it == __next; });
605 _Base::splice_after(__pos.base(), std::move(__list._M_base()),
606 __i.base());
607 }
608
609 void
610 splice_after(const_iterator __pos, forward_list& __list,
611 const_iterator __i)
612 { splice_after(__pos, std::move(__list), __i); }
613
614 void
615 splice_after(const_iterator __pos, forward_list&& __list,
616 const_iterator __before, const_iterator __last)
617 {
618 typename __gnu_debug::_Distance_traits<const_iterator>::__type __dist;
619 auto __listptr = std::__addressof(__list);
620 __glibcxx_check_insert_after(__pos);
621 __glibcxx_check_valid_fl_range(__before, __last, __dist);
622 _GLIBCXX_DEBUG_VERIFY(__before._M_attached_to(__listptr),
623 _M_message(__gnu_debug::__msg_splice_other)
624 ._M_sequence(__list, "list")
625 ._M_iterator(__before, "before"));
626 _GLIBCXX_DEBUG_VERIFY(__before._M_dereferenceable()
627 || __before._M_is_before_begin(),
628 _M_message(__gnu_debug::__msg_valid_range2)
629 ._M_sequence(__list, "list")
630 ._M_iterator(__before, "before")
631 ._M_iterator(__last, "last"));
632 _GLIBCXX_DEBUG_VERIFY(__before != __last,
633 _M_message(__gnu_debug::__msg_valid_range2)
634 ._M_sequence(__list, "list")
635 ._M_iterator(__before, "before")
636 ._M_iterator(__last, "last"));
637 _GLIBCXX_DEBUG_VERIFY(__list.get_allocator() == this->get_allocator(),
638 _M_message(__gnu_debug::__msg_splice_alloc)
639 ._M_sequence(*this)
640 ._M_sequence(__list, "__list"));
641
642 for (_Base_const_iterator __tmp = std::next(__before.base());
643 __tmp != __last.base(); ++__tmp)
644 {
645 _GLIBCXX_DEBUG_VERIFY(__tmp != __list._M_base().end(),
646 _M_message(__gnu_debug::__msg_valid_range2)
647 ._M_sequence(__list, "list")
648 ._M_iterator(__before, "before")
649 ._M_iterator(__last, "last"));
650 _GLIBCXX_DEBUG_VERIFY(__listptr != this || __tmp != __pos.base(),
651 _M_message(__gnu_debug::__msg_splice_overlap)
652 ._M_iterator(__tmp, "position")
653 ._M_iterator(__before, "before")
654 ._M_iterator(__last, "last"));
655 // _GLIBCXX_RESOLVE_LIB_DEFECTS
656 // 250. splicing invalidates iterators
657 this->_M_transfer_from_if(__list, [__tmp](_Base_const_iterator __it)
658 { return __it == __tmp; });
659 }
660
661 _Base::splice_after(__pos.base(), std::move(__list._M_base()),
662 __before.base(), __last.base());
663 }
664
665 void
666 splice_after(const_iterator __pos, forward_list& __list,
667 const_iterator __before, const_iterator __last)
668 { splice_after(__pos, std::move(__list), __before, __last); }
669
670 private:
671#if __cplusplus > 201703L
672 using __remove_return_type = size_type;
673# define _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG \
674 __attribute__((__abi_tag__("__cxx20")))
675# define _GLIBCXX20_ONLY(__expr) __expr
676#else
677 using __remove_return_type = void;
678# define _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
679# define _GLIBCXX20_ONLY(__expr)
680#endif
681
682 public:
683 _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
684 __remove_return_type
685 remove(const _Tp& __val)
686 {
687 if (!this->_M_iterators && !this->_M_const_iterators)
688 return _Base::remove(__val);
689
690 size_type __removed __attribute__((__unused__)) = 0;
691 _Base __to_destroy(get_allocator());
692 _Base_const_iterator __x = _Base::cbefore_begin();
693 _Base_const_iterator __old = __x++;
694 while (__x != _Base::cend())
695 {
696 if (*__x == __val)
697 {
698 _Base_const_iterator __next = std::next(__old);
699 this->_M_invalidate_if([__next](_Base_const_iterator __it)
700 { return __it == __next; });
701 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
702 _M_base(), __old);
703 __x = __old;
704 _GLIBCXX20_ONLY( __removed++ );
705 }
706
707 __old = __x++;
708 }
709
710 return _GLIBCXX20_ONLY( __removed );
711 }
712
713 template<typename _Pred>
714 __remove_return_type
715 remove_if(_Pred __pred)
716 {
717 if (!this->_M_iterators && !this->_M_const_iterators)
718 return _Base::remove_if(__pred);
719
720 size_type __removed __attribute__((__unused__)) = 0;
721 _Base __to_destroy(get_allocator());
722 _Base_iterator __x = _Base::before_begin();
723 _Base_iterator __old = __x++;
724 while (__x != _Base::end())
725 {
726 if (__pred(*__x))
727 {
728 this->_M_invalidate_if([__x](_Base_const_iterator __it)
729 { return __it == __x; });
730 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
731 _M_base(), __old);
732 __x = __old;
733 _GLIBCXX20_ONLY( __removed++ );
734 }
735
736 __old = __x++;
737 }
738
739 return _GLIBCXX20_ONLY( __removed );
740 }
741
742 _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
743 __remove_return_type
744 unique()
745 { return unique(std::equal_to<_Tp>()); }
746
747 template<typename _BinPred>
748 __remove_return_type
749 unique(_BinPred __binary_pred)
750 {
751 if (!this->_M_iterators && !this->_M_const_iterators)
752 return _Base::unique(__binary_pred);
753
754 _Base_const_iterator __first = _Base::cbegin();
755 _Base_const_iterator __last = _Base::cend();
756 if (__first == __last)
757 return _GLIBCXX20_ONLY(0);
758
759 size_type __removed __attribute__((__unused__)) = 0;
760 _Base __to_destroy(get_allocator());
761 _Base_const_iterator __next = std::next(__first);
762 while (__next != __last)
763 {
764 if (__binary_pred(*__first, *__next))
765 {
766 this->_M_invalidate_if([__next](_Base_const_iterator __it)
767 { return __it == __next; });
768 __to_destroy.splice_after(__to_destroy.cbefore_begin(),
769 _M_base(), __first);
770 __next = __first;
771 _GLIBCXX20_ONLY( __removed++ );
772 }
773
774 __first = __next++;
775 }
776
777 return _GLIBCXX20_ONLY( __removed );
778 }
779
780#undef _GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG
781#undef _GLIBCXX20_ONLY
782
783 void
784 merge(forward_list&& __list)
785 {
786 if (this != std::__addressof(__list))
787 {
788 __glibcxx_check_sorted(_Base::begin(), _Base::end());
789 __glibcxx_check_sorted(__list._M_base().begin(),
790 __list._M_base().end());
791 this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
792 {
793 return __it != __list._M_base().cbefore_begin()
794 && __it != __list._M_base().cend();
795 });
796 _Base::merge(std::move(__list._M_base()));
797 }
798 }
799
800 void
801 merge(forward_list& __list)
802 { merge(std::move(__list)); }
803
804 template<typename _Comp>
805 void
806 merge(forward_list&& __list, _Comp __comp)
807 {
808 if (this != std::__addressof(__list))
809 {
810 __glibcxx_check_sorted_pred(_Base::begin(), _Base::end(), __comp);
811 __glibcxx_check_sorted_pred(__list._M_base().begin(),
812 __list._M_base().end(), __comp);
813 this->_M_transfer_from_if(__list,
814 [&__list](_Base_const_iterator __it)
815 {
816 return __it != __list._M_base().cbefore_begin()
817 && __it != __list._M_base().cend();
818 });
819 _Base::merge(std::move(__list._M_base()), __comp);
820 }
821 }
822
823 template<typename _Comp>
824 void
825 merge(forward_list& __list, _Comp __comp)
826 { merge(std::move(__list), __comp); }
827
828 using _Base::sort;
829 using _Base::reverse;
830
831 _Base&
832 _M_base() noexcept { return *this; }
833
834 const _Base&
835 _M_base() const noexcept { return *this; }
836 };
837
838#if __cpp_deduction_guides >= 201606
839 template<typename _InputIterator, typename _ValT
840 = typename iterator_traits<_InputIterator>::value_type,
841 typename _Allocator = allocator<_ValT>,
842 typename = _RequireInputIter<_InputIterator>,
843 typename = _RequireAllocator<_Allocator>>
844 forward_list(_InputIterator, _InputIterator, _Allocator = _Allocator())
845 -> forward_list<_ValT, _Allocator>;
846
847 template<typename _Tp, typename _Allocator = allocator<_Tp>,
848 typename = _RequireAllocator<_Allocator>>
849 forward_list(size_t, _Tp, _Allocator = _Allocator())
850 -> forward_list<_Tp, _Allocator>;
851#endif
852
853 template<typename _Tp, typename _Alloc>
854 bool
855 operator==(const forward_list<_Tp, _Alloc>& __lx,
856 const forward_list<_Tp, _Alloc>& __ly)
857 { return __lx._M_base() == __ly._M_base(); }
858
859#if __cpp_lib_three_way_comparison
860 template<typename _Tp, typename _Alloc>
861 constexpr __detail::__synth3way_t<_Tp>
862 operator<=>(const forward_list<_Tp, _Alloc>& __x,
863 const forward_list<_Tp, _Alloc>& __y)
864 { return __x._M_base() <=> __y._M_base(); }
865#else
866 template<typename _Tp, typename _Alloc>
867 inline bool
868 operator<(const forward_list<_Tp, _Alloc>& __lx,
869 const forward_list<_Tp, _Alloc>& __ly)
870 { return __lx._M_base() < __ly._M_base(); }
871
872 template<typename _Tp, typename _Alloc>
873 inline bool
874 operator!=(const forward_list<_Tp, _Alloc>& __lx,
875 const forward_list<_Tp, _Alloc>& __ly)
876 { return !(__lx == __ly); }
877
878 /// Based on operator<
879 template<typename _Tp, typename _Alloc>
880 inline bool
881 operator>(const forward_list<_Tp, _Alloc>& __lx,
882 const forward_list<_Tp, _Alloc>& __ly)
883 { return (__ly < __lx); }
884
885 /// Based on operator<
886 template<typename _Tp, typename _Alloc>
887 inline bool
888 operator>=(const forward_list<_Tp, _Alloc>& __lx,
889 const forward_list<_Tp, _Alloc>& __ly)
890 { return !(__lx < __ly); }
891
892 /// Based on operator<
893 template<typename _Tp, typename _Alloc>
894 inline bool
895 operator<=(const forward_list<_Tp, _Alloc>& __lx,
896 const forward_list<_Tp, _Alloc>& __ly)
897 { return !(__ly < __lx); }
898#endif // three-way comparison
899
900 /// See std::forward_list::swap().
901 template<typename _Tp, typename _Alloc>
902 inline void
903 swap(forward_list<_Tp, _Alloc>& __lx, forward_list<_Tp, _Alloc>& __ly)
904 noexcept(noexcept(__lx.swap(__ly)))
905 { __lx.swap(__ly); }
906
907} // namespace __debug
908} // namespace std
909
910namespace __gnu_debug
911{
912 template<typename _Tp, typename _Alloc>
913 struct _BeforeBeginHelper<std::__debug::forward_list<_Tp, _Alloc> >
914 {
915 typedef std::__debug::forward_list<_Tp, _Alloc> _Sequence;
916
917 template<typename _Iterator>
918 static bool
919 _S_Is(const _Safe_iterator<_Iterator, _Sequence>& __it)
920 {
921 return
922 __it.base() == __it._M_get_sequence()->_M_base().before_begin();
923 }
924
925 template<typename _Iterator>
926 static bool
927 _S_Is_Beginnest(const _Safe_iterator<_Iterator, _Sequence>& __it)
928 { return _S_Is(__it); }
929 };
930
931 template<typename _Tp, typename _Alloc>
932 struct _Sequence_traits<std::__debug::forward_list<_Tp, _Alloc> >
933 {
934 typedef typename std::__debug::forward_list<_Tp, _Alloc>::iterator _It;
935
936 static typename _Distance_traits<_It>::__type
937 _S_size(const std::__debug::forward_list<_Tp, _Alloc>& __seq)
938 {
939 return __seq.empty()
940 ? std::make_pair(0, __dp_exact) : std::make_pair(1, __dp_sign);
941 }
942 };
943
944#ifndef _GLIBCXX_DEBUG_PEDANTIC
945 template<class _Tp, class _Alloc>
946 struct _Insert_range_from_self_is_safe<
947 std::__debug::forward_list<_Tp, _Alloc> >
948 { enum { __value = 1 }; };
949#endif
950}
951
952#endif