1 // Deque implementation -*- C++ -*-
3 // Copyright (C) 2001-2015 Free Software Foundation, Inc.
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)
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.
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.
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/>.
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40 * Silicon Graphics Computer Systems, Inc.
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51 /** @file bits/stl_deque.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{deque}
57 #define _STL_DEQUE_H 1
59 #include <bits/concept_check.h>
60 #include <bits/stl_iterator_base_types.h>
61 #include <bits/stl_iterator_base_funcs.h>
62 #if __cplusplus >= 201103L
63 #include <initializer_list>
66 namespace std _GLIBCXX_VISIBILITY(default)
68 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
71 * @brief This function controls the size of memory nodes.
72 * @param __size The size of an element.
73 * @return The number (not byte size) of elements per node.
75 * This function started off as a compiler kludge from SGI, but
76 * seems to be a useful wrapper around a repeated constant
77 * expression. The @b 512 is tunable (and no other code needs to
78 * change), but no investigation has been done since inheriting the
79 * SGI code. Touch _GLIBCXX_DEQUE_BUF_SIZE only if you know what
80 * you are doing, however: changing it breaks the binary
84 #ifndef _GLIBCXX_DEQUE_BUF_SIZE
85 #define _GLIBCXX_DEQUE_BUF_SIZE 512
88 _GLIBCXX_CONSTEXPR inline size_t
89 __deque_buf_size(size_t __size)
90 { return (__size < _GLIBCXX_DEQUE_BUF_SIZE
91 ? size_t(_GLIBCXX_DEQUE_BUF_SIZE / __size) : size_t(1)); }
95 * @brief A deque::iterator.
97 * Quite a bit of intelligence here. Much of the functionality of
98 * deque is actually passed off to this class. A deque holds two
99 * of these internally, marking its valid range. Access to
100 * elements is done as offsets of either of those two, relying on
101 * operator overloading in this class.
103 * All the functions are op overloads except for _M_set_node.
105 template<typename _Tp, typename _Ref, typename _Ptr>
106 struct _Deque_iterator
108 #if __cplusplus < 201103L
109 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator;
110 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator;
111 typedef _Tp* _Elt_pointer;
112 typedef _Tp** _Map_pointer;
115 template<typename _Up>
116 using __ptr_to = typename pointer_traits<_Ptr>::template rebind<_Up>;
117 template<typename _CvTp>
118 using __iter = _Deque_iterator<_Tp, _CvTp&, __ptr_to<_CvTp>>;
120 typedef __iter<_Tp> iterator;
121 typedef __iter<const _Tp> const_iterator;
122 typedef __ptr_to<_Tp> _Elt_pointer;
123 typedef __ptr_to<_Elt_pointer> _Map_pointer;
126 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT
127 { return __deque_buf_size(sizeof(_Tp)); }
129 typedef std::random_access_iterator_tag iterator_category;
130 typedef _Tp value_type;
131 typedef _Ptr pointer;
132 typedef _Ref reference;
133 typedef size_t size_type;
134 typedef ptrdiff_t difference_type;
135 typedef _Deque_iterator _Self;
138 _Elt_pointer _M_first;
139 _Elt_pointer _M_last;
140 _Map_pointer _M_node;
142 _Deque_iterator(_Elt_pointer __x, _Map_pointer __y) _GLIBCXX_NOEXCEPT
143 : _M_cur(__x), _M_first(*__y),
144 _M_last(*__y + _S_buffer_size()), _M_node(__y) { }
146 _Deque_iterator() _GLIBCXX_NOEXCEPT
147 : _M_cur(), _M_first(), _M_last(), _M_node() { }
149 _Deque_iterator(const iterator& __x) _GLIBCXX_NOEXCEPT
150 : _M_cur(__x._M_cur), _M_first(__x._M_first),
151 _M_last(__x._M_last), _M_node(__x._M_node) { }
154 _M_const_cast() const _GLIBCXX_NOEXCEPT
155 { return iterator(_M_cur, _M_node); }
158 operator*() const _GLIBCXX_NOEXCEPT
162 operator->() const _GLIBCXX_NOEXCEPT
166 operator++() _GLIBCXX_NOEXCEPT
169 if (_M_cur == _M_last)
171 _M_set_node(_M_node + 1);
178 operator++(int) _GLIBCXX_NOEXCEPT
186 operator--() _GLIBCXX_NOEXCEPT
188 if (_M_cur == _M_first)
190 _M_set_node(_M_node - 1);
198 operator--(int) _GLIBCXX_NOEXCEPT
206 operator+=(difference_type __n) _GLIBCXX_NOEXCEPT
208 const difference_type __offset = __n + (_M_cur - _M_first);
209 if (__offset >= 0 && __offset < difference_type(_S_buffer_size()))
213 const difference_type __node_offset =
214 __offset > 0 ? __offset / difference_type(_S_buffer_size())
215 : -difference_type((-__offset - 1)
216 / _S_buffer_size()) - 1;
217 _M_set_node(_M_node + __node_offset);
218 _M_cur = _M_first + (__offset - __node_offset
219 * difference_type(_S_buffer_size()));
225 operator+(difference_type __n) const _GLIBCXX_NOEXCEPT
232 operator-=(difference_type __n) _GLIBCXX_NOEXCEPT
233 { return *this += -__n; }
236 operator-(difference_type __n) const _GLIBCXX_NOEXCEPT
243 operator[](difference_type __n) const _GLIBCXX_NOEXCEPT
244 { return *(*this + __n); }
247 * Prepares to traverse new_node. Sets everything except
248 * _M_cur, which should therefore be set by the caller
249 * immediately afterwards, based on _M_first and _M_last.
252 _M_set_node(_Map_pointer __new_node) _GLIBCXX_NOEXCEPT
254 _M_node = __new_node;
255 _M_first = *__new_node;
256 _M_last = _M_first + difference_type(_S_buffer_size());
260 // Note: we also provide overloads whose operands are of the same type in
261 // order to avoid ambiguous overload resolution when std::rel_ops operators
262 // are in scope (for additional details, see libstdc++/3628)
263 template<typename _Tp, typename _Ref, typename _Ptr>
265 operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
266 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
267 { return __x._M_cur == __y._M_cur; }
269 template<typename _Tp, typename _RefL, typename _PtrL,
270 typename _RefR, typename _PtrR>
272 operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
273 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
274 { return __x._M_cur == __y._M_cur; }
276 template<typename _Tp, typename _Ref, typename _Ptr>
278 operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
279 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
280 { return !(__x == __y); }
282 template<typename _Tp, typename _RefL, typename _PtrL,
283 typename _RefR, typename _PtrR>
285 operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
286 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
287 { return !(__x == __y); }
289 template<typename _Tp, typename _Ref, typename _Ptr>
291 operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
292 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
293 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
294 : (__x._M_node < __y._M_node); }
296 template<typename _Tp, typename _RefL, typename _PtrL,
297 typename _RefR, typename _PtrR>
299 operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
300 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
301 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
302 : (__x._M_node < __y._M_node); }
304 template<typename _Tp, typename _Ref, typename _Ptr>
306 operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
307 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
308 { return __y < __x; }
310 template<typename _Tp, typename _RefL, typename _PtrL,
311 typename _RefR, typename _PtrR>
313 operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
314 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
315 { return __y < __x; }
317 template<typename _Tp, typename _Ref, typename _Ptr>
319 operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
320 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
321 { return !(__y < __x); }
323 template<typename _Tp, typename _RefL, typename _PtrL,
324 typename _RefR, typename _PtrR>
326 operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
327 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
328 { return !(__y < __x); }
330 template<typename _Tp, typename _Ref, typename _Ptr>
332 operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
333 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
334 { return !(__x < __y); }
336 template<typename _Tp, typename _RefL, typename _PtrL,
337 typename _RefR, typename _PtrR>
339 operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
340 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
341 { return !(__x < __y); }
343 // _GLIBCXX_RESOLVE_LIB_DEFECTS
344 // According to the resolution of DR179 not only the various comparison
345 // operators but also operator- must accept mixed iterator/const_iterator
347 template<typename _Tp, typename _Ref, typename _Ptr>
348 inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
349 operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
350 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT
352 return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
353 (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size())
354 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
355 + (__y._M_last - __y._M_cur);
358 template<typename _Tp, typename _RefL, typename _PtrL,
359 typename _RefR, typename _PtrR>
360 inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
361 operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
362 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT
364 return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
365 (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size())
366 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
367 + (__y._M_last - __y._M_cur);
370 template<typename _Tp, typename _Ref, typename _Ptr>
371 inline _Deque_iterator<_Tp, _Ref, _Ptr>
372 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x)
374 { return __x + __n; }
376 template<typename _Tp>
378 fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>&,
379 const _Deque_iterator<_Tp, _Tp&, _Tp*>&, const _Tp&);
381 template<typename _Tp>
382 _Deque_iterator<_Tp, _Tp&, _Tp*>
383 copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
384 _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
385 _Deque_iterator<_Tp, _Tp&, _Tp*>);
387 template<typename _Tp>
388 inline _Deque_iterator<_Tp, _Tp&, _Tp*>
389 copy(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
390 _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
391 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
392 { return std::copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first),
393 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last),
396 template<typename _Tp>
397 _Deque_iterator<_Tp, _Tp&, _Tp*>
398 copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
399 _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
400 _Deque_iterator<_Tp, _Tp&, _Tp*>);
402 template<typename _Tp>
403 inline _Deque_iterator<_Tp, _Tp&, _Tp*>
404 copy_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
405 _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
406 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
407 { return std::copy_backward(_Deque_iterator<_Tp,
408 const _Tp&, const _Tp*>(__first),
410 const _Tp&, const _Tp*>(__last),
413 #if __cplusplus >= 201103L
414 template<typename _Tp>
415 _Deque_iterator<_Tp, _Tp&, _Tp*>
416 move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
417 _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
418 _Deque_iterator<_Tp, _Tp&, _Tp*>);
420 template<typename _Tp>
421 inline _Deque_iterator<_Tp, _Tp&, _Tp*>
422 move(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
423 _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
424 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
425 { return std::move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first),
426 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last),
429 template<typename _Tp>
430 _Deque_iterator<_Tp, _Tp&, _Tp*>
431 move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
432 _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
433 _Deque_iterator<_Tp, _Tp&, _Tp*>);
435 template<typename _Tp>
436 inline _Deque_iterator<_Tp, _Tp&, _Tp*>
437 move_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
438 _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
439 _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
440 { return std::move_backward(_Deque_iterator<_Tp,
441 const _Tp&, const _Tp*>(__first),
443 const _Tp&, const _Tp*>(__last),
448 * Deque base class. This class provides the unified face for %deque's
449 * allocation. This class's constructor and destructor allocate and
450 * deallocate (but do not initialize) storage. This makes %exception
453 * Nothing in this class ever constructs or destroys an actual Tp element.
454 * (Deque handles that itself.) Only/All memory management is performed
457 template<typename _Tp, typename _Alloc>
461 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
462 rebind<_Tp>::other _Tp_alloc_type;
463 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits;
465 #if __cplusplus < 201103L
467 typedef const _Tp* _Ptr_const;
469 typedef typename _Alloc_traits::pointer _Ptr;
470 typedef typename _Alloc_traits::const_pointer _Ptr_const;
473 typedef typename _Alloc_traits::template rebind<_Ptr>::other
475 typedef __gnu_cxx::__alloc_traits<_Map_alloc_type> _Map_alloc_traits;
478 typedef _Alloc allocator_type;
479 typedef typename _Alloc_traits::size_type size_type;
482 get_allocator() const _GLIBCXX_NOEXCEPT
483 { return allocator_type(_M_get_Tp_allocator()); }
485 typedef _Deque_iterator<_Tp, _Tp&, _Ptr> iterator;
486 typedef _Deque_iterator<_Tp, const _Tp&, _Ptr_const> const_iterator;
490 { _M_initialize_map(0); }
492 _Deque_base(size_t __num_elements)
494 { _M_initialize_map(__num_elements); }
496 _Deque_base(const allocator_type& __a, size_t __num_elements)
498 { _M_initialize_map(__num_elements); }
500 _Deque_base(const allocator_type& __a)
502 { /* Caller must initialize map. */ }
504 #if __cplusplus >= 201103L
505 _Deque_base(_Deque_base&& __x, false_type)
506 : _M_impl(__x._M_move_impl())
509 _Deque_base(_Deque_base&& __x, true_type)
510 : _M_impl(std::move(__x._M_get_Tp_allocator()))
512 _M_initialize_map(0);
513 if (__x._M_impl._M_map)
514 this->_M_impl._M_swap_data(__x._M_impl);
517 _Deque_base(_Deque_base&& __x)
518 : _Deque_base(std::move(__x),
519 __gnu_cxx::__allocator_always_compares_equal<_Alloc>{})
522 _Deque_base(_Deque_base&& __x, const allocator_type& __a, size_type __n)
525 if (__x.get_allocator() == __a)
527 if (__x._M_impl._M_map)
529 _M_initialize_map(0);
530 this->_M_impl._M_swap_data(__x._M_impl);
535 _M_initialize_map(__n);
540 ~_Deque_base() _GLIBCXX_NOEXCEPT;
543 typedef typename iterator::_Map_pointer _Map_pointer;
545 //This struct encapsulates the implementation of the std::deque
546 //standard container and at the same time makes use of the EBO
547 //for empty allocators.
549 : public _Tp_alloc_type
557 : _Tp_alloc_type(), _M_map(), _M_map_size(0),
558 _M_start(), _M_finish()
561 _Deque_impl(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT
562 : _Tp_alloc_type(__a), _M_map(), _M_map_size(0),
563 _M_start(), _M_finish()
566 #if __cplusplus >= 201103L
567 _Deque_impl(_Deque_impl&&) = default;
569 _Deque_impl(_Tp_alloc_type&& __a) noexcept
570 : _Tp_alloc_type(std::move(__a)), _M_map(), _M_map_size(0),
571 _M_start(), _M_finish()
575 void _M_swap_data(_Deque_impl& __x) _GLIBCXX_NOEXCEPT
578 swap(this->_M_start, __x._M_start);
579 swap(this->_M_finish, __x._M_finish);
580 swap(this->_M_map, __x._M_map);
581 swap(this->_M_map_size, __x._M_map_size);
586 _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT
587 { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); }
589 const _Tp_alloc_type&
590 _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT
591 { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); }
594 _M_get_map_allocator() const _GLIBCXX_NOEXCEPT
595 { return _Map_alloc_type(_M_get_Tp_allocator()); }
600 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits;
601 return _Traits::allocate(_M_impl, __deque_buf_size(sizeof(_Tp)));
605 _M_deallocate_node(_Ptr __p) _GLIBCXX_NOEXCEPT
607 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits;
608 _Traits::deallocate(_M_impl, __p, __deque_buf_size(sizeof(_Tp)));
612 _M_allocate_map(size_t __n)
614 _Map_alloc_type __map_alloc = _M_get_map_allocator();
615 return _Map_alloc_traits::allocate(__map_alloc, __n);
619 _M_deallocate_map(_Map_pointer __p, size_t __n) _GLIBCXX_NOEXCEPT
621 _Map_alloc_type __map_alloc = _M_get_map_allocator();
622 _Map_alloc_traits::deallocate(__map_alloc, __p, __n);
626 void _M_initialize_map(size_t);
627 void _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish);
628 void _M_destroy_nodes(_Map_pointer __nstart,
629 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT;
630 enum { _S_initial_map_size = 8 };
634 #if __cplusplus >= 201103L
640 return std::move(_M_impl);
642 // Create a copy of the current allocator.
643 _Tp_alloc_type __alloc{_M_get_Tp_allocator()};
644 // Put that copy in a moved-from state.
645 _Tp_alloc_type __sink __attribute((__unused__)) {std::move(__alloc)};
646 // Create an empty map that allocates using the moved-from allocator.
647 _Deque_base __empty{__alloc};
648 __empty._M_initialize_map(0);
649 // Now safe to modify current allocator and perform non-throwing swaps.
650 _Deque_impl __ret{std::move(_M_get_Tp_allocator())};
651 _M_impl._M_swap_data(__ret);
652 _M_impl._M_swap_data(__empty._M_impl);
658 template<typename _Tp, typename _Alloc>
659 _Deque_base<_Tp, _Alloc>::
660 ~_Deque_base() _GLIBCXX_NOEXCEPT
662 if (this->_M_impl._M_map)
664 _M_destroy_nodes(this->_M_impl._M_start._M_node,
665 this->_M_impl._M_finish._M_node + 1);
666 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
671 * @brief Layout storage.
672 * @param __num_elements The count of T's for which to allocate space
676 * The initial underlying memory layout is a bit complicated...
678 template<typename _Tp, typename _Alloc>
680 _Deque_base<_Tp, _Alloc>::
681 _M_initialize_map(size_t __num_elements)
683 const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp))
686 this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size,
687 size_t(__num_nodes + 2));
688 this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size);
690 // For "small" maps (needing less than _M_map_size nodes), allocation
691 // starts in the middle elements and grows outwards. So nstart may be
692 // the beginning of _M_map, but for small maps it may be as far in as
695 _Map_pointer __nstart = (this->_M_impl._M_map
696 + (this->_M_impl._M_map_size - __num_nodes) / 2);
697 _Map_pointer __nfinish = __nstart + __num_nodes;
700 { _M_create_nodes(__nstart, __nfinish); }
703 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
704 this->_M_impl._M_map = _Map_pointer();
705 this->_M_impl._M_map_size = 0;
706 __throw_exception_again;
709 this->_M_impl._M_start._M_set_node(__nstart);
710 this->_M_impl._M_finish._M_set_node(__nfinish - 1);
711 this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first;
712 this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first
714 % __deque_buf_size(sizeof(_Tp)));
717 template<typename _Tp, typename _Alloc>
719 _Deque_base<_Tp, _Alloc>::
720 _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish)
725 for (__cur = __nstart; __cur < __nfinish; ++__cur)
726 *__cur = this->_M_allocate_node();
730 _M_destroy_nodes(__nstart, __cur);
731 __throw_exception_again;
735 template<typename _Tp, typename _Alloc>
737 _Deque_base<_Tp, _Alloc>::
738 _M_destroy_nodes(_Map_pointer __nstart,
739 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT
741 for (_Map_pointer __n = __nstart; __n < __nfinish; ++__n)
742 _M_deallocate_node(*__n);
746 * @brief A standard container using fixed-size memory allocation and
747 * constant-time manipulation of elements at either end.
751 * @tparam _Tp Type of element.
752 * @tparam _Alloc Allocator type, defaults to allocator<_Tp>.
754 * Meets the requirements of a <a href="tables.html#65">container</a>, a
755 * <a href="tables.html#66">reversible container</a>, and a
756 * <a href="tables.html#67">sequence</a>, including the
757 * <a href="tables.html#68">optional sequence requirements</a>.
759 * In previous HP/SGI versions of deque, there was an extra template
760 * parameter so users could control the node size. This extension turned
761 * out to violate the C++ standard (it can be detected using template
762 * template parameters), and it was removed.
764 * Here's how a deque<Tp> manages memory. Each deque has 4 members:
767 * - size_t _M_map_size
768 * - iterator _M_start, _M_finish
770 * map_size is at least 8. %map is an array of map_size
771 * pointers-to-@a nodes. (The name %map has nothing to do with the
772 * std::map class, and @b nodes should not be confused with
773 * std::list's usage of @a node.)
775 * A @a node has no specific type name as such, but it is referred
776 * to as @a node in this file. It is a simple array-of-Tp. If Tp
777 * is very large, there will be one Tp element per node (i.e., an
778 * @a array of one). For non-huge Tp's, node size is inversely
779 * related to Tp size: the larger the Tp, the fewer Tp's will fit
780 * in a node. The goal here is to keep the total size of a node
781 * relatively small and constant over different Tp's, to improve
782 * allocator efficiency.
784 * Not every pointer in the %map array will point to a node. If
785 * the initial number of elements in the deque is small, the
786 * /middle/ %map pointers will be valid, and the ones at the edges
787 * will be unused. This same situation will arise as the %map
788 * grows: available %map pointers, if any, will be on the ends. As
789 * new nodes are created, only a subset of the %map's pointers need
790 * to be copied @a outward.
793 * - For any nonsingular iterator i:
794 * - i.node points to a member of the %map array. (Yes, you read that
795 * correctly: i.node does not actually point to a node.) The member of
796 * the %map array is what actually points to the node.
797 * - i.first == *(i.node) (This points to the node (first Tp element).)
798 * - i.last == i.first + node_size
799 * - i.cur is a pointer in the range [i.first, i.last). NOTE:
800 * the implication of this is that i.cur is always a dereferenceable
801 * pointer, even if i is a past-the-end iterator.
802 * - Start and Finish are always nonsingular iterators. NOTE: this
803 * means that an empty deque must have one node, a deque with <N
804 * elements (where N is the node buffer size) must have one node, a
805 * deque with N through (2N-1) elements must have two nodes, etc.
806 * - For every node other than start.node and finish.node, every
807 * element in the node is an initialized object. If start.node ==
808 * finish.node, then [start.cur, finish.cur) are initialized
809 * objects, and the elements outside that range are uninitialized
810 * storage. Otherwise, [start.cur, start.last) and [finish.first,
811 * finish.cur) are initialized objects, and [start.first, start.cur)
812 * and [finish.cur, finish.last) are uninitialized storage.
813 * - [%map, %map + map_size) is a valid, non-empty range.
814 * - [start.node, finish.node] is a valid range contained within
815 * [%map, %map + map_size).
816 * - A pointer in the range [%map, %map + map_size) points to an allocated
817 * node if and only if the pointer is in the range
818 * [start.node, finish.node].
820 * Here's the magic: nothing in deque is @b aware of the discontiguous
823 * The memory setup and layout occurs in the parent, _Base, and the iterator
824 * class is entirely responsible for @a leaping from one node to the next.
825 * All the implementation routines for deque itself work only through the
826 * start and finish iterators. This keeps the routines simple and sane,
827 * and we can use other standard algorithms as well.
829 template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
830 class deque : protected _Deque_base<_Tp, _Alloc>
832 // concept requirements
833 typedef typename _Alloc::value_type _Alloc_value_type;
834 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
835 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
837 typedef _Deque_base<_Tp, _Alloc> _Base;
838 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type;
839 typedef typename _Base::_Alloc_traits _Alloc_traits;
840 typedef typename _Base::_Map_pointer _Map_pointer;
843 typedef _Tp value_type;
844 typedef typename _Alloc_traits::pointer pointer;
845 typedef typename _Alloc_traits::const_pointer const_pointer;
846 typedef typename _Alloc_traits::reference reference;
847 typedef typename _Alloc_traits::const_reference const_reference;
848 typedef typename _Base::iterator iterator;
849 typedef typename _Base::const_iterator const_iterator;
850 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
851 typedef std::reverse_iterator<iterator> reverse_iterator;
852 typedef size_t size_type;
853 typedef ptrdiff_t difference_type;
854 typedef _Alloc allocator_type;
857 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT
858 { return __deque_buf_size(sizeof(_Tp)); }
860 // Functions controlling memory layout, and nothing else.
861 using _Base::_M_initialize_map;
862 using _Base::_M_create_nodes;
863 using _Base::_M_destroy_nodes;
864 using _Base::_M_allocate_node;
865 using _Base::_M_deallocate_node;
866 using _Base::_M_allocate_map;
867 using _Base::_M_deallocate_map;
868 using _Base::_M_get_Tp_allocator;
871 * A total of four data members accumulated down the hierarchy.
872 * May be accessed via _M_impl.*
874 using _Base::_M_impl;
877 // [23.2.1.1] construct/copy/destroy
878 // (assign() and get_allocator() are also listed in this section)
881 * @brief Creates a %deque with no elements.
883 deque() : _Base() { }
886 * @brief Creates a %deque with no elements.
887 * @param __a An allocator object.
890 deque(const allocator_type& __a)
893 #if __cplusplus >= 201103L
895 * @brief Creates a %deque with default constructed elements.
896 * @param __n The number of elements to initially create.
898 * This constructor fills the %deque with @a n default
899 * constructed elements.
902 deque(size_type __n, const allocator_type& __a = allocator_type())
904 { _M_default_initialize(); }
907 * @brief Creates a %deque with copies of an exemplar element.
908 * @param __n The number of elements to initially create.
909 * @param __value An element to copy.
910 * @param __a An allocator.
912 * This constructor fills the %deque with @a __n copies of @a __value.
914 deque(size_type __n, const value_type& __value,
915 const allocator_type& __a = allocator_type())
917 { _M_fill_initialize(__value); }
920 * @brief Creates a %deque with copies of an exemplar element.
921 * @param __n The number of elements to initially create.
922 * @param __value An element to copy.
923 * @param __a An allocator.
925 * This constructor fills the %deque with @a __n copies of @a __value.
928 deque(size_type __n, const value_type& __value = value_type(),
929 const allocator_type& __a = allocator_type())
931 { _M_fill_initialize(__value); }
935 * @brief %Deque copy constructor.
936 * @param __x A %deque of identical element and allocator types.
938 * The newly-created %deque uses a copy of the allocation object used
941 deque(const deque& __x)
942 : _Base(_Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()),
944 { std::__uninitialized_copy_a(__x.begin(), __x.end(),
945 this->_M_impl._M_start,
946 _M_get_Tp_allocator()); }
948 #if __cplusplus >= 201103L
950 * @brief %Deque move constructor.
951 * @param __x A %deque of identical element and allocator types.
953 * The newly-created %deque contains the exact contents of @a __x.
954 * The contents of @a __x are a valid, but unspecified %deque.
957 : _Base(std::move(__x)) { }
959 /// Copy constructor with alternative allocator
960 deque(const deque& __x, const allocator_type& __a)
961 : _Base(__a, __x.size())
962 { std::__uninitialized_copy_a(__x.begin(), __x.end(),
963 this->_M_impl._M_start,
964 _M_get_Tp_allocator()); }
966 /// Move constructor with alternative allocator
967 deque(deque&& __x, const allocator_type& __a)
968 : _Base(std::move(__x), __a, __x.size())
970 if (__x.get_allocator() != __a)
972 std::__uninitialized_move_a(__x.begin(), __x.end(),
973 this->_M_impl._M_start,
974 _M_get_Tp_allocator());
980 * @brief Builds a %deque from an initializer list.
981 * @param __l An initializer_list.
982 * @param __a An allocator object.
984 * Create a %deque consisting of copies of the elements in the
985 * initializer_list @a __l.
987 * This will call the element type's copy constructor N times
988 * (where N is __l.size()) and do no memory reallocation.
990 deque(initializer_list<value_type> __l,
991 const allocator_type& __a = allocator_type())
994 _M_range_initialize(__l.begin(), __l.end(),
995 random_access_iterator_tag());
1000 * @brief Builds a %deque from a range.
1001 * @param __first An input iterator.
1002 * @param __last An input iterator.
1003 * @param __a An allocator object.
1005 * Create a %deque consisting of copies of the elements from [__first,
1008 * If the iterators are forward, bidirectional, or random-access, then
1009 * this will call the elements' copy constructor N times (where N is
1010 * distance(__first,__last)) and do no memory reallocation. But if only
1011 * input iterators are used, then this will do at most 2N calls to the
1012 * copy constructor, and logN memory reallocations.
1014 #if __cplusplus >= 201103L
1015 template<typename _InputIterator,
1016 typename = std::_RequireInputIter<_InputIterator>>
1017 deque(_InputIterator __first, _InputIterator __last,
1018 const allocator_type& __a = allocator_type())
1020 { _M_initialize_dispatch(__first, __last, __false_type()); }
1022 template<typename _InputIterator>
1023 deque(_InputIterator __first, _InputIterator __last,
1024 const allocator_type& __a = allocator_type())
1027 // Check whether it's an integral type. If so, it's not an iterator.
1028 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1029 _M_initialize_dispatch(__first, __last, _Integral());
1034 * The dtor only erases the elements, and note that if the elements
1035 * themselves are pointers, the pointed-to memory is not touched in any
1036 * way. Managing the pointer is the user's responsibility.
1039 { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); }
1042 * @brief %Deque assignment operator.
1043 * @param __x A %deque of identical element and allocator types.
1045 * All the elements of @a x are copied, but unlike the copy constructor,
1046 * the allocator object is not copied.
1049 operator=(const deque& __x);
1051 #if __cplusplus >= 201103L
1053 * @brief %Deque move assignment operator.
1054 * @param __x A %deque of identical element and allocator types.
1056 * The contents of @a __x are moved into this deque (without copying,
1057 * if the allocators permit it).
1058 * @a __x is a valid, but unspecified %deque.
1061 operator=(deque&& __x) noexcept(_Alloc_traits::_S_always_equal())
1063 constexpr bool __always_equal = _Alloc_traits::_S_always_equal();
1064 _M_move_assign1(std::move(__x),
1065 integral_constant<bool, __always_equal>());
1070 * @brief Assigns an initializer list to a %deque.
1071 * @param __l An initializer_list.
1073 * This function fills a %deque with copies of the elements in the
1074 * initializer_list @a __l.
1076 * Note that the assignment completely changes the %deque and that the
1077 * resulting %deque's size is the same as the number of elements
1078 * assigned. Old data may be lost.
1081 operator=(initializer_list<value_type> __l)
1083 this->assign(__l.begin(), __l.end());
1089 * @brief Assigns a given value to a %deque.
1090 * @param __n Number of elements to be assigned.
1091 * @param __val Value to be assigned.
1093 * This function fills a %deque with @a n copies of the given
1094 * value. Note that the assignment completely changes the
1095 * %deque and that the resulting %deque's size is the same as
1096 * the number of elements assigned. Old data may be lost.
1099 assign(size_type __n, const value_type& __val)
1100 { _M_fill_assign(__n, __val); }
1103 * @brief Assigns a range to a %deque.
1104 * @param __first An input iterator.
1105 * @param __last An input iterator.
1107 * This function fills a %deque with copies of the elements in the
1108 * range [__first,__last).
1110 * Note that the assignment completely changes the %deque and that the
1111 * resulting %deque's size is the same as the number of elements
1112 * assigned. Old data may be lost.
1114 #if __cplusplus >= 201103L
1115 template<typename _InputIterator,
1116 typename = std::_RequireInputIter<_InputIterator>>
1118 assign(_InputIterator __first, _InputIterator __last)
1119 { _M_assign_dispatch(__first, __last, __false_type()); }
1121 template<typename _InputIterator>
1123 assign(_InputIterator __first, _InputIterator __last)
1125 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1126 _M_assign_dispatch(__first, __last, _Integral());
1130 #if __cplusplus >= 201103L
1132 * @brief Assigns an initializer list to a %deque.
1133 * @param __l An initializer_list.
1135 * This function fills a %deque with copies of the elements in the
1136 * initializer_list @a __l.
1138 * Note that the assignment completely changes the %deque and that the
1139 * resulting %deque's size is the same as the number of elements
1140 * assigned. Old data may be lost.
1143 assign(initializer_list<value_type> __l)
1144 { this->assign(__l.begin(), __l.end()); }
1147 /// Get a copy of the memory allocation object.
1149 get_allocator() const _GLIBCXX_NOEXCEPT
1150 { return _Base::get_allocator(); }
1154 * Returns a read/write iterator that points to the first element in the
1155 * %deque. Iteration is done in ordinary element order.
1158 begin() _GLIBCXX_NOEXCEPT
1159 { return this->_M_impl._M_start; }
1162 * Returns a read-only (constant) iterator that points to the first
1163 * element in the %deque. Iteration is done in ordinary element order.
1166 begin() const _GLIBCXX_NOEXCEPT
1167 { return this->_M_impl._M_start; }
1170 * Returns a read/write iterator that points one past the last
1171 * element in the %deque. Iteration is done in ordinary
1175 end() _GLIBCXX_NOEXCEPT
1176 { return this->_M_impl._M_finish; }
1179 * Returns a read-only (constant) iterator that points one past
1180 * the last element in the %deque. Iteration is done in
1181 * ordinary element order.
1184 end() const _GLIBCXX_NOEXCEPT
1185 { return this->_M_impl._M_finish; }
1188 * Returns a read/write reverse iterator that points to the
1189 * last element in the %deque. Iteration is done in reverse
1193 rbegin() _GLIBCXX_NOEXCEPT
1194 { return reverse_iterator(this->_M_impl._M_finish); }
1197 * Returns a read-only (constant) reverse iterator that points
1198 * to the last element in the %deque. Iteration is done in
1199 * reverse element order.
1201 const_reverse_iterator
1202 rbegin() const _GLIBCXX_NOEXCEPT
1203 { return const_reverse_iterator(this->_M_impl._M_finish); }
1206 * Returns a read/write reverse iterator that points to one
1207 * before the first element in the %deque. Iteration is done
1208 * in reverse element order.
1211 rend() _GLIBCXX_NOEXCEPT
1212 { return reverse_iterator(this->_M_impl._M_start); }
1215 * Returns a read-only (constant) reverse iterator that points
1216 * to one before the first element in the %deque. Iteration is
1217 * done in reverse element order.
1219 const_reverse_iterator
1220 rend() const _GLIBCXX_NOEXCEPT
1221 { return const_reverse_iterator(this->_M_impl._M_start); }
1223 #if __cplusplus >= 201103L
1225 * Returns a read-only (constant) iterator that points to the first
1226 * element in the %deque. Iteration is done in ordinary element order.
1229 cbegin() const noexcept
1230 { return this->_M_impl._M_start; }
1233 * Returns a read-only (constant) iterator that points one past
1234 * the last element in the %deque. Iteration is done in
1235 * ordinary element order.
1238 cend() const noexcept
1239 { return this->_M_impl._M_finish; }
1242 * Returns a read-only (constant) reverse iterator that points
1243 * to the last element in the %deque. Iteration is done in
1244 * reverse element order.
1246 const_reverse_iterator
1247 crbegin() const noexcept
1248 { return const_reverse_iterator(this->_M_impl._M_finish); }
1251 * Returns a read-only (constant) reverse iterator that points
1252 * to one before the first element in the %deque. Iteration is
1253 * done in reverse element order.
1255 const_reverse_iterator
1256 crend() const noexcept
1257 { return const_reverse_iterator(this->_M_impl._M_start); }
1260 // [23.2.1.2] capacity
1261 /** Returns the number of elements in the %deque. */
1263 size() const _GLIBCXX_NOEXCEPT
1264 { return this->_M_impl._M_finish - this->_M_impl._M_start; }
1266 /** Returns the size() of the largest possible %deque. */
1268 max_size() const _GLIBCXX_NOEXCEPT
1269 { return _Alloc_traits::max_size(_M_get_Tp_allocator()); }
1271 #if __cplusplus >= 201103L
1273 * @brief Resizes the %deque to the specified number of elements.
1274 * @param __new_size Number of elements the %deque should contain.
1276 * This function will %resize the %deque to the specified
1277 * number of elements. If the number is smaller than the
1278 * %deque's current size the %deque is truncated, otherwise
1279 * default constructed elements are appended.
1282 resize(size_type __new_size)
1284 const size_type __len = size();
1285 if (__new_size > __len)
1286 _M_default_append(__new_size - __len);
1287 else if (__new_size < __len)
1288 _M_erase_at_end(this->_M_impl._M_start
1289 + difference_type(__new_size));
1293 * @brief Resizes the %deque to the specified number of elements.
1294 * @param __new_size Number of elements the %deque should contain.
1295 * @param __x Data with which new elements should be populated.
1297 * This function will %resize the %deque to the specified
1298 * number of elements. If the number is smaller than the
1299 * %deque's current size the %deque is truncated, otherwise the
1300 * %deque is extended and new elements are populated with given
1304 resize(size_type __new_size, const value_type& __x)
1306 const size_type __len = size();
1307 if (__new_size > __len)
1308 insert(this->_M_impl._M_finish, __new_size - __len, __x);
1309 else if (__new_size < __len)
1310 _M_erase_at_end(this->_M_impl._M_start
1311 + difference_type(__new_size));
1315 * @brief Resizes the %deque to the specified number of elements.
1316 * @param __new_size Number of elements the %deque should contain.
1317 * @param __x Data with which new elements should be populated.
1319 * This function will %resize the %deque to the specified
1320 * number of elements. If the number is smaller than the
1321 * %deque's current size the %deque is truncated, otherwise the
1322 * %deque is extended and new elements are populated with given
1326 resize(size_type __new_size, value_type __x = value_type())
1328 const size_type __len = size();
1329 if (__new_size > __len)
1330 insert(this->_M_impl._M_finish, __new_size - __len, __x);
1331 else if (__new_size < __len)
1332 _M_erase_at_end(this->_M_impl._M_start
1333 + difference_type(__new_size));
1337 #if __cplusplus >= 201103L
1338 /** A non-binding request to reduce memory use. */
1340 shrink_to_fit() noexcept
1341 { _M_shrink_to_fit(); }
1345 * Returns true if the %deque is empty. (Thus begin() would
1349 empty() const _GLIBCXX_NOEXCEPT
1350 { return this->_M_impl._M_finish == this->_M_impl._M_start; }
1354 * @brief Subscript access to the data contained in the %deque.
1355 * @param __n The index of the element for which data should be
1357 * @return Read/write reference to data.
1359 * This operator allows for easy, array-style, data access.
1360 * Note that data access with this operator is unchecked and
1361 * out_of_range lookups are not defined. (For checked lookups
1365 operator[](size_type __n) _GLIBCXX_NOEXCEPT
1366 { return this->_M_impl._M_start[difference_type(__n)]; }
1369 * @brief Subscript access to the data contained in the %deque.
1370 * @param __n The index of the element for which data should be
1372 * @return Read-only (constant) reference to data.
1374 * This operator allows for easy, array-style, data access.
1375 * Note that data access with this operator is unchecked and
1376 * out_of_range lookups are not defined. (For checked lookups
1380 operator[](size_type __n) const _GLIBCXX_NOEXCEPT
1381 { return this->_M_impl._M_start[difference_type(__n)]; }
1384 /// Safety check used only from at().
1386 _M_range_check(size_type __n) const
1388 if (__n >= this->size())
1389 __throw_out_of_range_fmt(__N("deque::_M_range_check: __n "
1390 "(which is %zu)>= this->size() "
1397 * @brief Provides access to the data contained in the %deque.
1398 * @param __n The index of the element for which data should be
1400 * @return Read/write reference to data.
1401 * @throw std::out_of_range If @a __n is an invalid index.
1403 * This function provides for safer data access. The parameter
1404 * is first checked that it is in the range of the deque. The
1405 * function throws out_of_range if the check fails.
1410 _M_range_check(__n);
1411 return (*this)[__n];
1415 * @brief Provides access to the data contained in the %deque.
1416 * @param __n The index of the element for which data should be
1418 * @return Read-only (constant) reference to data.
1419 * @throw std::out_of_range If @a __n is an invalid index.
1421 * This function provides for safer data access. The parameter is first
1422 * checked that it is in the range of the deque. The function throws
1423 * out_of_range if the check fails.
1426 at(size_type __n) const
1428 _M_range_check(__n);
1429 return (*this)[__n];
1433 * Returns a read/write reference to the data at the first
1434 * element of the %deque.
1437 front() _GLIBCXX_NOEXCEPT
1438 { return *begin(); }
1441 * Returns a read-only (constant) reference to the data at the first
1442 * element of the %deque.
1445 front() const _GLIBCXX_NOEXCEPT
1446 { return *begin(); }
1449 * Returns a read/write reference to the data at the last element of the
1453 back() _GLIBCXX_NOEXCEPT
1455 iterator __tmp = end();
1461 * Returns a read-only (constant) reference to the data at the last
1462 * element of the %deque.
1465 back() const _GLIBCXX_NOEXCEPT
1467 const_iterator __tmp = end();
1472 // [23.2.1.2] modifiers
1474 * @brief Add data to the front of the %deque.
1475 * @param __x Data to be added.
1477 * This is a typical stack operation. The function creates an
1478 * element at the front of the %deque and assigns the given
1479 * data to it. Due to the nature of a %deque this operation
1480 * can be done in constant time.
1483 push_front(const value_type& __x)
1485 if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first)
1487 _Alloc_traits::construct(this->_M_impl,
1488 this->_M_impl._M_start._M_cur - 1,
1490 --this->_M_impl._M_start._M_cur;
1493 _M_push_front_aux(__x);
1496 #if __cplusplus >= 201103L
1498 push_front(value_type&& __x)
1499 { emplace_front(std::move(__x)); }
1501 template<typename... _Args>
1503 emplace_front(_Args&&... __args);
1507 * @brief Add data to the end of the %deque.
1508 * @param __x Data to be added.
1510 * This is a typical stack operation. The function creates an
1511 * element at the end of the %deque and assigns the given data
1512 * to it. Due to the nature of a %deque this operation can be
1513 * done in constant time.
1516 push_back(const value_type& __x)
1518 if (this->_M_impl._M_finish._M_cur
1519 != this->_M_impl._M_finish._M_last - 1)
1521 _Alloc_traits::construct(this->_M_impl,
1522 this->_M_impl._M_finish._M_cur, __x);
1523 ++this->_M_impl._M_finish._M_cur;
1526 _M_push_back_aux(__x);
1529 #if __cplusplus >= 201103L
1531 push_back(value_type&& __x)
1532 { emplace_back(std::move(__x)); }
1534 template<typename... _Args>
1536 emplace_back(_Args&&... __args);
1540 * @brief Removes first element.
1542 * This is a typical stack operation. It shrinks the %deque by one.
1544 * Note that no data is returned, and if the first element's data is
1545 * needed, it should be retrieved before pop_front() is called.
1548 pop_front() _GLIBCXX_NOEXCEPT
1550 if (this->_M_impl._M_start._M_cur
1551 != this->_M_impl._M_start._M_last - 1)
1553 _Alloc_traits::destroy(this->_M_impl,
1554 this->_M_impl._M_start._M_cur);
1555 ++this->_M_impl._M_start._M_cur;
1562 * @brief Removes last element.
1564 * This is a typical stack operation. It shrinks the %deque by one.
1566 * Note that no data is returned, and if the last element's data is
1567 * needed, it should be retrieved before pop_back() is called.
1570 pop_back() _GLIBCXX_NOEXCEPT
1572 if (this->_M_impl._M_finish._M_cur
1573 != this->_M_impl._M_finish._M_first)
1575 --this->_M_impl._M_finish._M_cur;
1576 _Alloc_traits::destroy(this->_M_impl,
1577 this->_M_impl._M_finish._M_cur);
1583 #if __cplusplus >= 201103L
1585 * @brief Inserts an object in %deque before specified iterator.
1586 * @param __position A const_iterator into the %deque.
1587 * @param __args Arguments.
1588 * @return An iterator that points to the inserted data.
1590 * This function will insert an object of type T constructed
1591 * with T(std::forward<Args>(args)...) before the specified location.
1593 template<typename... _Args>
1595 emplace(const_iterator __position, _Args&&... __args);
1598 * @brief Inserts given value into %deque before specified iterator.
1599 * @param __position A const_iterator into the %deque.
1600 * @param __x Data to be inserted.
1601 * @return An iterator that points to the inserted data.
1603 * This function will insert a copy of the given value before the
1604 * specified location.
1607 insert(const_iterator __position, const value_type& __x);
1610 * @brief Inserts given value into %deque before specified iterator.
1611 * @param __position An iterator into the %deque.
1612 * @param __x Data to be inserted.
1613 * @return An iterator that points to the inserted data.
1615 * This function will insert a copy of the given value before the
1616 * specified location.
1619 insert(iterator __position, const value_type& __x);
1622 #if __cplusplus >= 201103L
1624 * @brief Inserts given rvalue into %deque before specified iterator.
1625 * @param __position A const_iterator into the %deque.
1626 * @param __x Data to be inserted.
1627 * @return An iterator that points to the inserted data.
1629 * This function will insert a copy of the given rvalue before the
1630 * specified location.
1633 insert(const_iterator __position, value_type&& __x)
1634 { return emplace(__position, std::move(__x)); }
1637 * @brief Inserts an initializer list into the %deque.
1638 * @param __p An iterator into the %deque.
1639 * @param __l An initializer_list.
1641 * This function will insert copies of the data in the
1642 * initializer_list @a __l into the %deque before the location
1643 * specified by @a __p. This is known as <em>list insert</em>.
1646 insert(const_iterator __p, initializer_list<value_type> __l)
1647 { return this->insert(__p, __l.begin(), __l.end()); }
1650 #if __cplusplus >= 201103L
1652 * @brief Inserts a number of copies of given data into the %deque.
1653 * @param __position A const_iterator into the %deque.
1654 * @param __n Number of elements to be inserted.
1655 * @param __x Data to be inserted.
1656 * @return An iterator that points to the inserted data.
1658 * This function will insert a specified number of copies of the given
1659 * data before the location specified by @a __position.
1662 insert(const_iterator __position, size_type __n, const value_type& __x)
1664 difference_type __offset = __position - cbegin();
1665 _M_fill_insert(__position._M_const_cast(), __n, __x);
1666 return begin() + __offset;
1670 * @brief Inserts a number of copies of given data into the %deque.
1671 * @param __position An iterator into the %deque.
1672 * @param __n Number of elements to be inserted.
1673 * @param __x Data to be inserted.
1675 * This function will insert a specified number of copies of the given
1676 * data before the location specified by @a __position.
1679 insert(iterator __position, size_type __n, const value_type& __x)
1680 { _M_fill_insert(__position, __n, __x); }
1683 #if __cplusplus >= 201103L
1685 * @brief Inserts a range into the %deque.
1686 * @param __position A const_iterator into the %deque.
1687 * @param __first An input iterator.
1688 * @param __last An input iterator.
1689 * @return An iterator that points to the inserted data.
1691 * This function will insert copies of the data in the range
1692 * [__first,__last) into the %deque before the location specified
1693 * by @a __position. This is known as <em>range insert</em>.
1695 template<typename _InputIterator,
1696 typename = std::_RequireInputIter<_InputIterator>>
1698 insert(const_iterator __position, _InputIterator __first,
1699 _InputIterator __last)
1701 difference_type __offset = __position - cbegin();
1702 _M_insert_dispatch(__position._M_const_cast(),
1703 __first, __last, __false_type());
1704 return begin() + __offset;
1708 * @brief Inserts a range into the %deque.
1709 * @param __position An iterator into the %deque.
1710 * @param __first An input iterator.
1711 * @param __last An input iterator.
1713 * This function will insert copies of the data in the range
1714 * [__first,__last) into the %deque before the location specified
1715 * by @a __position. This is known as <em>range insert</em>.
1717 template<typename _InputIterator>
1719 insert(iterator __position, _InputIterator __first,
1720 _InputIterator __last)
1722 // Check whether it's an integral type. If so, it's not an iterator.
1723 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1724 _M_insert_dispatch(__position, __first, __last, _Integral());
1729 * @brief Remove element at given position.
1730 * @param __position Iterator pointing to element to be erased.
1731 * @return An iterator pointing to the next element (or end()).
1733 * This function will erase the element at the given position and thus
1734 * shorten the %deque by one.
1736 * The user is cautioned that
1737 * this function only erases the element, and that if the element is
1738 * itself a pointer, the pointed-to memory is not touched in any way.
1739 * Managing the pointer is the user's responsibility.
1742 #if __cplusplus >= 201103L
1743 erase(const_iterator __position)
1745 erase(iterator __position)
1747 { return _M_erase(__position._M_const_cast()); }
1750 * @brief Remove a range of elements.
1751 * @param __first Iterator pointing to the first element to be erased.
1752 * @param __last Iterator pointing to one past the last element to be
1754 * @return An iterator pointing to the element pointed to by @a last
1755 * prior to erasing (or end()).
1757 * This function will erase the elements in the range
1758 * [__first,__last) and shorten the %deque accordingly.
1760 * The user is cautioned that
1761 * this function only erases the elements, and that if the elements
1762 * themselves are pointers, the pointed-to memory is not touched in any
1763 * way. Managing the pointer is the user's responsibility.
1766 #if __cplusplus >= 201103L
1767 erase(const_iterator __first, const_iterator __last)
1769 erase(iterator __first, iterator __last)
1771 { return _M_erase(__first._M_const_cast(), __last._M_const_cast()); }
1774 * @brief Swaps data with another %deque.
1775 * @param __x A %deque of the same element and allocator types.
1777 * This exchanges the elements between two deques in constant time.
1778 * (Four pointers, so it should be quite fast.)
1779 * Note that the global std::swap() function is specialized such that
1780 * std::swap(d1,d2) will feed to this function.
1784 #if __cplusplus >= 201103L
1785 noexcept(_Alloc_traits::_S_nothrow_swap())
1788 _M_impl._M_swap_data(__x._M_impl);
1789 _Alloc_traits::_S_on_swap(_M_get_Tp_allocator(),
1790 __x._M_get_Tp_allocator());
1794 * Erases all the elements. Note that this function only erases the
1795 * elements, and that if the elements themselves are pointers, the
1796 * pointed-to memory is not touched in any way. Managing the pointer is
1797 * the user's responsibility.
1800 clear() _GLIBCXX_NOEXCEPT
1801 { _M_erase_at_end(begin()); }
1804 // Internal constructor functions follow.
1806 // called by the range constructor to implement [23.1.1]/9
1808 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1809 // 438. Ambiguity in the "do the right thing" clause
1810 template<typename _Integer>
1812 _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type)
1814 _M_initialize_map(static_cast<size_type>(__n));
1815 _M_fill_initialize(__x);
1818 // called by the range constructor to implement [23.1.1]/9
1819 template<typename _InputIterator>
1821 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
1824 typedef typename std::iterator_traits<_InputIterator>::
1825 iterator_category _IterCategory;
1826 _M_range_initialize(__first, __last, _IterCategory());
1829 // called by the second initialize_dispatch above
1832 * @brief Fills the deque with whatever is in [first,last).
1833 * @param __first An input iterator.
1834 * @param __last An input iterator.
1837 * If the iterators are actually forward iterators (or better), then the
1838 * memory layout can be done all at once. Else we move forward using
1839 * push_back on each value from the iterator.
1841 template<typename _InputIterator>
1843 _M_range_initialize(_InputIterator __first, _InputIterator __last,
1844 std::input_iterator_tag);
1846 // called by the second initialize_dispatch above
1847 template<typename _ForwardIterator>
1849 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
1850 std::forward_iterator_tag);
1854 * @brief Fills the %deque with copies of value.
1855 * @param __value Initial value.
1857 * @pre _M_start and _M_finish have already been initialized,
1858 * but none of the %deque's elements have yet been constructed.
1860 * This function is called only when the user provides an explicit size
1861 * (with or without an explicit exemplar value).
1864 _M_fill_initialize(const value_type& __value);
1866 #if __cplusplus >= 201103L
1867 // called by deque(n).
1869 _M_default_initialize();
1872 // Internal assign functions follow. The *_aux functions do the actual
1873 // assignment work for the range versions.
1875 // called by the range assign to implement [23.1.1]/9
1877 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1878 // 438. Ambiguity in the "do the right thing" clause
1879 template<typename _Integer>
1881 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
1882 { _M_fill_assign(__n, __val); }
1884 // called by the range assign to implement [23.1.1]/9
1885 template<typename _InputIterator>
1887 _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
1890 typedef typename std::iterator_traits<_InputIterator>::
1891 iterator_category _IterCategory;
1892 _M_assign_aux(__first, __last, _IterCategory());
1895 // called by the second assign_dispatch above
1896 template<typename _InputIterator>
1898 _M_assign_aux(_InputIterator __first, _InputIterator __last,
1899 std::input_iterator_tag);
1901 // called by the second assign_dispatch above
1902 template<typename _ForwardIterator>
1904 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
1905 std::forward_iterator_tag)
1907 const size_type __len = std::distance(__first, __last);
1910 _ForwardIterator __mid = __first;
1911 std::advance(__mid, size());
1912 std::copy(__first, __mid, begin());
1913 insert(end(), __mid, __last);
1916 _M_erase_at_end(std::copy(__first, __last, begin()));
1919 // Called by assign(n,t), and the range assign when it turns out
1920 // to be the same thing.
1922 _M_fill_assign(size_type __n, const value_type& __val)
1926 std::fill(begin(), end(), __val);
1927 insert(end(), __n - size(), __val);
1931 _M_erase_at_end(begin() + difference_type(__n));
1932 std::fill(begin(), end(), __val);
1937 /// Helper functions for push_* and pop_*.
1938 #if __cplusplus < 201103L
1939 void _M_push_back_aux(const value_type&);
1941 void _M_push_front_aux(const value_type&);
1943 template<typename... _Args>
1944 void _M_push_back_aux(_Args&&... __args);
1946 template<typename... _Args>
1947 void _M_push_front_aux(_Args&&... __args);
1950 void _M_pop_back_aux();
1952 void _M_pop_front_aux();
1955 // Internal insert functions follow. The *_aux functions do the actual
1956 // insertion work when all shortcuts fail.
1958 // called by the range insert to implement [23.1.1]/9
1960 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1961 // 438. Ambiguity in the "do the right thing" clause
1962 template<typename _Integer>
1964 _M_insert_dispatch(iterator __pos,
1965 _Integer __n, _Integer __x, __true_type)
1966 { _M_fill_insert(__pos, __n, __x); }
1968 // called by the range insert to implement [23.1.1]/9
1969 template<typename _InputIterator>
1971 _M_insert_dispatch(iterator __pos,
1972 _InputIterator __first, _InputIterator __last,
1975 typedef typename std::iterator_traits<_InputIterator>::
1976 iterator_category _IterCategory;
1977 _M_range_insert_aux(__pos, __first, __last, _IterCategory());
1980 // called by the second insert_dispatch above
1981 template<typename _InputIterator>
1983 _M_range_insert_aux(iterator __pos, _InputIterator __first,
1984 _InputIterator __last, std::input_iterator_tag);
1986 // called by the second insert_dispatch above
1987 template<typename _ForwardIterator>
1989 _M_range_insert_aux(iterator __pos, _ForwardIterator __first,
1990 _ForwardIterator __last, std::forward_iterator_tag);
1992 // Called by insert(p,n,x), and the range insert when it turns out to be
1993 // the same thing. Can use fill functions in optimal situations,
1994 // otherwise passes off to insert_aux(p,n,x).
1996 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);
1998 // called by insert(p,x)
1999 #if __cplusplus < 201103L
2001 _M_insert_aux(iterator __pos, const value_type& __x);
2003 template<typename... _Args>
2005 _M_insert_aux(iterator __pos, _Args&&... __args);
2008 // called by insert(p,n,x) via fill_insert
2010 _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);
2012 // called by range_insert_aux for forward iterators
2013 template<typename _ForwardIterator>
2015 _M_insert_aux(iterator __pos,
2016 _ForwardIterator __first, _ForwardIterator __last,
2020 // Internal erase functions follow.
2023 _M_destroy_data_aux(iterator __first, iterator __last);
2025 // Called by ~deque().
2026 // NB: Doesn't deallocate the nodes.
2027 template<typename _Alloc1>
2029 _M_destroy_data(iterator __first, iterator __last, const _Alloc1&)
2030 { _M_destroy_data_aux(__first, __last); }
2033 _M_destroy_data(iterator __first, iterator __last,
2034 const std::allocator<_Tp>&)
2036 if (!__has_trivial_destructor(value_type))
2037 _M_destroy_data_aux(__first, __last);
2040 // Called by erase(q1, q2).
2042 _M_erase_at_begin(iterator __pos)
2044 _M_destroy_data(begin(), __pos, _M_get_Tp_allocator());
2045 _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node);
2046 this->_M_impl._M_start = __pos;
2049 // Called by erase(q1, q2), resize(), clear(), _M_assign_aux,
2050 // _M_fill_assign, operator=.
2052 _M_erase_at_end(iterator __pos)
2054 _M_destroy_data(__pos, end(), _M_get_Tp_allocator());
2055 _M_destroy_nodes(__pos._M_node + 1,
2056 this->_M_impl._M_finish._M_node + 1);
2057 this->_M_impl._M_finish = __pos;
2061 _M_erase(iterator __pos);
2064 _M_erase(iterator __first, iterator __last);
2066 #if __cplusplus >= 201103L
2067 // Called by resize(sz).
2069 _M_default_append(size_type __n);
2076 /// Memory-handling helpers for the previous internal insert functions.
2078 _M_reserve_elements_at_front(size_type __n)
2080 const size_type __vacancies = this->_M_impl._M_start._M_cur
2081 - this->_M_impl._M_start._M_first;
2082 if (__n > __vacancies)
2083 _M_new_elements_at_front(__n - __vacancies);
2084 return this->_M_impl._M_start - difference_type(__n);
2088 _M_reserve_elements_at_back(size_type __n)
2090 const size_type __vacancies = (this->_M_impl._M_finish._M_last
2091 - this->_M_impl._M_finish._M_cur) - 1;
2092 if (__n > __vacancies)
2093 _M_new_elements_at_back(__n - __vacancies);
2094 return this->_M_impl._M_finish + difference_type(__n);
2098 _M_new_elements_at_front(size_type __new_elements);
2101 _M_new_elements_at_back(size_type __new_elements);
2107 * @brief Memory-handling helpers for the major %map.
2109 * Makes sure the _M_map has space for new nodes. Does not
2110 * actually add the nodes. Can invalidate _M_map pointers.
2111 * (And consequently, %deque iterators.)
2114 _M_reserve_map_at_back(size_type __nodes_to_add = 1)
2116 if (__nodes_to_add + 1 > this->_M_impl._M_map_size
2117 - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map))
2118 _M_reallocate_map(__nodes_to_add, false);
2122 _M_reserve_map_at_front(size_type __nodes_to_add = 1)
2124 if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node
2125 - this->_M_impl._M_map))
2126 _M_reallocate_map(__nodes_to_add, true);
2130 _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);
2133 #if __cplusplus >= 201103L
2134 // Constant-time, nothrow move assignment when source object's memory
2135 // can be moved because the allocators are equal.
2137 _M_move_assign1(deque&& __x, /* always equal: */ true_type) noexcept
2139 this->_M_impl._M_swap_data(__x._M_impl);
2141 std::__alloc_on_move(_M_get_Tp_allocator(), __x._M_get_Tp_allocator());
2145 _M_move_assign1(deque&& __x, /* always equal: */ false_type)
2147 constexpr bool __move_storage =
2148 _Alloc_traits::_S_propagate_on_move_assign();
2149 _M_move_assign2(std::move(__x),
2150 integral_constant<bool, __move_storage>());
2153 // Destroy all elements and deallocate all memory, then replace
2154 // with elements created from __args.
2155 template<typename... _Args>
2157 _M_replace_map(_Args&&... __args)
2159 // Create new data first, so if allocation fails there are no effects.
2160 deque __newobj(std::forward<_Args>(__args)...);
2161 // Free existing storage using existing allocator.
2163 _M_deallocate_node(*begin()._M_node); // one node left after clear()
2164 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
2165 this->_M_impl._M_map = nullptr;
2166 this->_M_impl._M_map_size = 0;
2167 // Take ownership of replacement memory.
2168 this->_M_impl._M_swap_data(__newobj._M_impl);
2171 // Do move assignment when the allocator propagates.
2173 _M_move_assign2(deque&& __x, /* propagate: */ true_type)
2175 // Make a copy of the original allocator state.
2176 auto __alloc = __x._M_get_Tp_allocator();
2177 // The allocator propagates so storage can be moved from __x,
2178 // leaving __x in a valid empty state with a moved-from allocator.
2179 _M_replace_map(std::move(__x));
2180 // Move the corresponding allocator state too.
2181 _M_get_Tp_allocator() = std::move(__alloc);
2184 // Do move assignment when it may not be possible to move source
2185 // object's memory, resulting in a linear-time operation.
2187 _M_move_assign2(deque&& __x, /* propagate: */ false_type)
2189 if (__x._M_get_Tp_allocator() == this->_M_get_Tp_allocator())
2191 // The allocators are equal so storage can be moved from __x,
2192 // leaving __x in a valid empty state with its current allocator.
2193 _M_replace_map(std::move(__x), __x.get_allocator());
2197 // The rvalue's allocator cannot be moved and is not equal,
2198 // so we need to individually move each element.
2199 this->assign(std::__make_move_if_noexcept_iterator(__x.begin()),
2200 std::__make_move_if_noexcept_iterator(__x.end()));
2209 * @brief Deque equality comparison.
2210 * @param __x A %deque.
2211 * @param __y A %deque of the same type as @a __x.
2212 * @return True iff the size and elements of the deques are equal.
2214 * This is an equivalence relation. It is linear in the size of the
2215 * deques. Deques are considered equivalent if their sizes are equal,
2216 * and if corresponding elements compare equal.
2218 template<typename _Tp, typename _Alloc>
2220 operator==(const deque<_Tp, _Alloc>& __x,
2221 const deque<_Tp, _Alloc>& __y)
2222 { return __x.size() == __y.size()
2223 && std::equal(__x.begin(), __x.end(), __y.begin()); }
2226 * @brief Deque ordering relation.
2227 * @param __x A %deque.
2228 * @param __y A %deque of the same type as @a __x.
2229 * @return True iff @a x is lexicographically less than @a __y.
2231 * This is a total ordering relation. It is linear in the size of the
2232 * deques. The elements must be comparable with @c <.
2234 * See std::lexicographical_compare() for how the determination is made.
2236 template<typename _Tp, typename _Alloc>
2238 operator<(const deque<_Tp, _Alloc>& __x,
2239 const deque<_Tp, _Alloc>& __y)
2240 { return std::lexicographical_compare(__x.begin(), __x.end(),
2241 __y.begin(), __y.end()); }
2243 /// Based on operator==
2244 template<typename _Tp, typename _Alloc>
2246 operator!=(const deque<_Tp, _Alloc>& __x,
2247 const deque<_Tp, _Alloc>& __y)
2248 { return !(__x == __y); }
2250 /// Based on operator<
2251 template<typename _Tp, typename _Alloc>
2253 operator>(const deque<_Tp, _Alloc>& __x,
2254 const deque<_Tp, _Alloc>& __y)
2255 { return __y < __x; }
2257 /// Based on operator<
2258 template<typename _Tp, typename _Alloc>
2260 operator<=(const deque<_Tp, _Alloc>& __x,
2261 const deque<_Tp, _Alloc>& __y)
2262 { return !(__y < __x); }
2264 /// Based on operator<
2265 template<typename _Tp, typename _Alloc>
2267 operator>=(const deque<_Tp, _Alloc>& __x,
2268 const deque<_Tp, _Alloc>& __y)
2269 { return !(__x < __y); }
2271 /// See std::deque::swap().
2272 template<typename _Tp, typename _Alloc>
2274 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y)
2277 #undef _GLIBCXX_DEQUE_BUF_SIZE
2279 _GLIBCXX_END_NAMESPACE_CONTAINER
2282 #endif /* _STL_DEQUE_H */