libstdc++
stl_deque.h
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1 // Deque implementation -*- C++ -*-
2 
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 // 2011 Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20 
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25 
26 /*
27  *
28  * Copyright (c) 1994
29  * Hewlett-Packard Company
30  *
31  * Permission to use, copy, modify, distribute and sell this software
32  * and its documentation for any purpose is hereby granted without fee,
33  * provided that the above copyright notice appear in all copies and
34  * that both that copyright notice and this permission notice appear
35  * in supporting documentation. Hewlett-Packard Company makes no
36  * representations about the suitability of this software for any
37  * purpose. It is provided "as is" without express or implied warranty.
38  *
39  *
40  * Copyright (c) 1997
41  * Silicon Graphics Computer Systems, Inc.
42  *
43  * Permission to use, copy, modify, distribute and sell this software
44  * and its documentation for any purpose is hereby granted without fee,
45  * provided that the above copyright notice appear in all copies and
46  * that both that copyright notice and this permission notice appear
47  * in supporting documentation. Silicon Graphics makes no
48  * representations about the suitability of this software for any
49  * purpose. It is provided "as is" without express or implied warranty.
50  */
51 
52 /** @file bits/stl_deque.h
53  * This is an internal header file, included by other library headers.
54  * Do not attempt to use it directly. @headername{deque}
55  */
56 
57 #ifndef _STL_DEQUE_H
58 #define _STL_DEQUE_H 1
59 
60 #include <bits/concept_check.h>
63 #ifdef __GXX_EXPERIMENTAL_CXX0X__
64 #include <initializer_list>
65 #endif
66 
67 namespace std _GLIBCXX_VISIBILITY(default)
68 {
69 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
70 
71  /**
72  * @brief This function controls the size of memory nodes.
73  * @param __size The size of an element.
74  * @return The number (not byte size) of elements per node.
75  *
76  * This function started off as a compiler kludge from SGI, but
77  * seems to be a useful wrapper around a repeated constant
78  * expression. The @b 512 is tunable (and no other code needs to
79  * change), but no investigation has been done since inheriting the
80  * SGI code. Touch _GLIBCXX_DEQUE_BUF_SIZE only if you know what
81  * you are doing, however: changing it breaks the binary
82  * compatibility!!
83  */
84 
85 #ifndef _GLIBCXX_DEQUE_BUF_SIZE
86 #define _GLIBCXX_DEQUE_BUF_SIZE 512
87 #endif
88 
89  inline size_t
90  __deque_buf_size(size_t __size)
91  { return (__size < _GLIBCXX_DEQUE_BUF_SIZE
92  ? size_t(_GLIBCXX_DEQUE_BUF_SIZE / __size) : size_t(1)); }
93 
94 
95  /**
96  * @brief A deque::iterator.
97  *
98  * Quite a bit of intelligence here. Much of the functionality of
99  * deque is actually passed off to this class. A deque holds two
100  * of these internally, marking its valid range. Access to
101  * elements is done as offsets of either of those two, relying on
102  * operator overloading in this class.
103  *
104  * All the functions are op overloads except for _M_set_node.
105  */
106  template<typename _Tp, typename _Ref, typename _Ptr>
108  {
111 
112  static size_t _S_buffer_size()
113  { return __deque_buf_size(sizeof(_Tp)); }
114 
116  typedef _Tp value_type;
117  typedef _Ptr pointer;
118  typedef _Ref reference;
119  typedef size_t size_type;
120  typedef ptrdiff_t difference_type;
121  typedef _Tp** _Map_pointer;
122  typedef _Deque_iterator _Self;
123 
124  _Tp* _M_cur;
125  _Tp* _M_first;
126  _Tp* _M_last;
127  _Map_pointer _M_node;
128 
129  _Deque_iterator(_Tp* __x, _Map_pointer __y)
130  : _M_cur(__x), _M_first(*__y),
131  _M_last(*__y + _S_buffer_size()), _M_node(__y) { }
132 
134  : _M_cur(0), _M_first(0), _M_last(0), _M_node(0) { }
135 
136  _Deque_iterator(const iterator& __x)
137  : _M_cur(__x._M_cur), _M_first(__x._M_first),
138  _M_last(__x._M_last), _M_node(__x._M_node) { }
139 
140  reference
141  operator*() const
142  { return *_M_cur; }
143 
144  pointer
145  operator->() const
146  { return _M_cur; }
147 
148  _Self&
149  operator++()
150  {
151  ++_M_cur;
152  if (_M_cur == _M_last)
153  {
154  _M_set_node(_M_node + 1);
155  _M_cur = _M_first;
156  }
157  return *this;
158  }
159 
160  _Self
161  operator++(int)
162  {
163  _Self __tmp = *this;
164  ++*this;
165  return __tmp;
166  }
167 
168  _Self&
169  operator--()
170  {
171  if (_M_cur == _M_first)
172  {
173  _M_set_node(_M_node - 1);
174  _M_cur = _M_last;
175  }
176  --_M_cur;
177  return *this;
178  }
179 
180  _Self
181  operator--(int)
182  {
183  _Self __tmp = *this;
184  --*this;
185  return __tmp;
186  }
187 
188  _Self&
189  operator+=(difference_type __n)
190  {
191  const difference_type __offset = __n + (_M_cur - _M_first);
192  if (__offset >= 0 && __offset < difference_type(_S_buffer_size()))
193  _M_cur += __n;
194  else
195  {
196  const difference_type __node_offset =
197  __offset > 0 ? __offset / difference_type(_S_buffer_size())
198  : -difference_type((-__offset - 1)
199  / _S_buffer_size()) - 1;
200  _M_set_node(_M_node + __node_offset);
201  _M_cur = _M_first + (__offset - __node_offset
202  * difference_type(_S_buffer_size()));
203  }
204  return *this;
205  }
206 
207  _Self
208  operator+(difference_type __n) const
209  {
210  _Self __tmp = *this;
211  return __tmp += __n;
212  }
213 
214  _Self&
215  operator-=(difference_type __n)
216  { return *this += -__n; }
217 
218  _Self
219  operator-(difference_type __n) const
220  {
221  _Self __tmp = *this;
222  return __tmp -= __n;
223  }
224 
225  reference
226  operator[](difference_type __n) const
227  { return *(*this + __n); }
228 
229  /**
230  * Prepares to traverse new_node. Sets everything except
231  * _M_cur, which should therefore be set by the caller
232  * immediately afterwards, based on _M_first and _M_last.
233  */
234  void
235  _M_set_node(_Map_pointer __new_node)
236  {
237  _M_node = __new_node;
238  _M_first = *__new_node;
239  _M_last = _M_first + difference_type(_S_buffer_size());
240  }
241  };
242 
243  // Note: we also provide overloads whose operands are of the same type in
244  // order to avoid ambiguous overload resolution when std::rel_ops operators
245  // are in scope (for additional details, see libstdc++/3628)
246  template<typename _Tp, typename _Ref, typename _Ptr>
247  inline bool
248  operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
249  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
250  { return __x._M_cur == __y._M_cur; }
251 
252  template<typename _Tp, typename _RefL, typename _PtrL,
253  typename _RefR, typename _PtrR>
254  inline bool
255  operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
256  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
257  { return __x._M_cur == __y._M_cur; }
258 
259  template<typename _Tp, typename _Ref, typename _Ptr>
260  inline bool
261  operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
262  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
263  { return !(__x == __y); }
264 
265  template<typename _Tp, typename _RefL, typename _PtrL,
266  typename _RefR, typename _PtrR>
267  inline bool
268  operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
269  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
270  { return !(__x == __y); }
271 
272  template<typename _Tp, typename _Ref, typename _Ptr>
273  inline bool
274  operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
275  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
276  { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
277  : (__x._M_node < __y._M_node); }
278 
279  template<typename _Tp, typename _RefL, typename _PtrL,
280  typename _RefR, typename _PtrR>
281  inline bool
282  operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
283  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
284  { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
285  : (__x._M_node < __y._M_node); }
286 
287  template<typename _Tp, typename _Ref, typename _Ptr>
288  inline bool
289  operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
290  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
291  { return __y < __x; }
292 
293  template<typename _Tp, typename _RefL, typename _PtrL,
294  typename _RefR, typename _PtrR>
295  inline bool
296  operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
297  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
298  { return __y < __x; }
299 
300  template<typename _Tp, typename _Ref, typename _Ptr>
301  inline bool
302  operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
303  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
304  { return !(__y < __x); }
305 
306  template<typename _Tp, typename _RefL, typename _PtrL,
307  typename _RefR, typename _PtrR>
308  inline bool
309  operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
310  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
311  { return !(__y < __x); }
312 
313  template<typename _Tp, typename _Ref, typename _Ptr>
314  inline bool
315  operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
316  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
317  { return !(__x < __y); }
318 
319  template<typename _Tp, typename _RefL, typename _PtrL,
320  typename _RefR, typename _PtrR>
321  inline bool
322  operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
323  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
324  { return !(__x < __y); }
325 
326  // _GLIBCXX_RESOLVE_LIB_DEFECTS
327  // According to the resolution of DR179 not only the various comparison
328  // operators but also operator- must accept mixed iterator/const_iterator
329  // parameters.
330  template<typename _Tp, typename _Ref, typename _Ptr>
331  inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
332  operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
333  const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
334  {
335  return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
336  (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size())
337  * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
338  + (__y._M_last - __y._M_cur);
339  }
340 
341  template<typename _Tp, typename _RefL, typename _PtrL,
342  typename _RefR, typename _PtrR>
343  inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
344  operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
345  const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
346  {
347  return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
348  (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size())
349  * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
350  + (__y._M_last - __y._M_cur);
351  }
352 
353  template<typename _Tp, typename _Ref, typename _Ptr>
354  inline _Deque_iterator<_Tp, _Ref, _Ptr>
355  operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x)
356  { return __x + __n; }
357 
358  template<typename _Tp>
359  void
360  fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>&,
361  const _Deque_iterator<_Tp, _Tp&, _Tp*>&, const _Tp&);
362 
363  template<typename _Tp>
364  _Deque_iterator<_Tp, _Tp&, _Tp*>
365  copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
366  _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
367  _Deque_iterator<_Tp, _Tp&, _Tp*>);
368 
369  template<typename _Tp>
370  inline _Deque_iterator<_Tp, _Tp&, _Tp*>
371  copy(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
372  _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
373  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
374  { return std::copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first),
375  _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last),
376  __result); }
377 
378  template<typename _Tp>
379  _Deque_iterator<_Tp, _Tp&, _Tp*>
380  copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
381  _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
382  _Deque_iterator<_Tp, _Tp&, _Tp*>);
383 
384  template<typename _Tp>
385  inline _Deque_iterator<_Tp, _Tp&, _Tp*>
386  copy_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
387  _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
388  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
389  { return std::copy_backward(_Deque_iterator<_Tp,
390  const _Tp&, const _Tp*>(__first),
391  _Deque_iterator<_Tp,
392  const _Tp&, const _Tp*>(__last),
393  __result); }
394 
395 #ifdef __GXX_EXPERIMENTAL_CXX0X__
396  template<typename _Tp>
397  _Deque_iterator<_Tp, _Tp&, _Tp*>
398  move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
399  _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
400  _Deque_iterator<_Tp, _Tp&, _Tp*>);
401 
402  template<typename _Tp>
403  inline _Deque_iterator<_Tp, _Tp&, _Tp*>
404  move(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
405  _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
406  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
407  { return std::move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first),
408  _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last),
409  __result); }
410 
411  template<typename _Tp>
412  _Deque_iterator<_Tp, _Tp&, _Tp*>
413  move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>,
414  _Deque_iterator<_Tp, const _Tp&, const _Tp*>,
415  _Deque_iterator<_Tp, _Tp&, _Tp*>);
416 
417  template<typename _Tp>
418  inline _Deque_iterator<_Tp, _Tp&, _Tp*>
419  move_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first,
420  _Deque_iterator<_Tp, _Tp&, _Tp*> __last,
421  _Deque_iterator<_Tp, _Tp&, _Tp*> __result)
422  { return std::move_backward(_Deque_iterator<_Tp,
423  const _Tp&, const _Tp*>(__first),
424  _Deque_iterator<_Tp,
425  const _Tp&, const _Tp*>(__last),
426  __result); }
427 #endif
428 
429  /**
430  * Deque base class. This class provides the unified face for %deque's
431  * allocation. This class's constructor and destructor allocate and
432  * deallocate (but do not initialize) storage. This makes %exception
433  * safety easier.
434  *
435  * Nothing in this class ever constructs or destroys an actual Tp element.
436  * (Deque handles that itself.) Only/All memory management is performed
437  * here.
438  */
439  template<typename _Tp, typename _Alloc>
441  {
442  public:
443  typedef _Alloc allocator_type;
444 
445  allocator_type
446  get_allocator() const _GLIBCXX_NOEXCEPT
447  { return allocator_type(_M_get_Tp_allocator()); }
448 
451 
452  _Deque_base()
453  : _M_impl()
454  { _M_initialize_map(0); }
455 
456  _Deque_base(size_t __num_elements)
457  : _M_impl()
458  { _M_initialize_map(__num_elements); }
459 
460  _Deque_base(const allocator_type& __a, size_t __num_elements)
461  : _M_impl(__a)
462  { _M_initialize_map(__num_elements); }
463 
464  _Deque_base(const allocator_type& __a)
465  : _M_impl(__a)
466  { }
467 
468 #ifdef __GXX_EXPERIMENTAL_CXX0X__
469  _Deque_base(_Deque_base&& __x)
470  : _M_impl(std::move(__x._M_get_Tp_allocator()))
471  {
473  if (__x._M_impl._M_map)
474  {
475  std::swap(this->_M_impl._M_start, __x._M_impl._M_start);
476  std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish);
477  std::swap(this->_M_impl._M_map, __x._M_impl._M_map);
478  std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size);
479  }
480  }
481 #endif
482 
483  ~_Deque_base();
484 
485  protected:
486  //This struct encapsulates the implementation of the std::deque
487  //standard container and at the same time makes use of the EBO
488  //for empty allocators.
489  typedef typename _Alloc::template rebind<_Tp*>::other _Map_alloc_type;
490 
491  typedef typename _Alloc::template rebind<_Tp>::other _Tp_alloc_type;
492 
493  struct _Deque_impl
494  : public _Tp_alloc_type
495  {
496  _Tp** _M_map;
497  size_t _M_map_size;
498  iterator _M_start;
499  iterator _M_finish;
500 
501  _Deque_impl()
502  : _Tp_alloc_type(), _M_map(0), _M_map_size(0),
503  _M_start(), _M_finish()
504  { }
505 
506  _Deque_impl(const _Tp_alloc_type& __a)
507  : _Tp_alloc_type(__a), _M_map(0), _M_map_size(0),
508  _M_start(), _M_finish()
509  { }
510 
511 #ifdef __GXX_EXPERIMENTAL_CXX0X__
512  _Deque_impl(_Tp_alloc_type&& __a)
513  : _Tp_alloc_type(std::move(__a)), _M_map(0), _M_map_size(0),
514  _M_start(), _M_finish()
515  { }
516 #endif
517  };
518 
519  _Tp_alloc_type&
520  _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT
521  { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); }
522 
523  const _Tp_alloc_type&
524  _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT
525  { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); }
526 
527  _Map_alloc_type
528  _M_get_map_allocator() const _GLIBCXX_NOEXCEPT
529  { return _Map_alloc_type(_M_get_Tp_allocator()); }
530 
531  _Tp*
532  _M_allocate_node()
533  {
534  return _M_impl._Tp_alloc_type::allocate(__deque_buf_size(sizeof(_Tp)));
535  }
536 
537  void
538  _M_deallocate_node(_Tp* __p)
539  {
540  _M_impl._Tp_alloc_type::deallocate(__p, __deque_buf_size(sizeof(_Tp)));
541  }
542 
543  _Tp**
544  _M_allocate_map(size_t __n)
545  { return _M_get_map_allocator().allocate(__n); }
546 
547  void
548  _M_deallocate_map(_Tp** __p, size_t __n)
549  { _M_get_map_allocator().deallocate(__p, __n); }
550 
551  protected:
552  void _M_initialize_map(size_t);
553  void _M_create_nodes(_Tp** __nstart, _Tp** __nfinish);
554  void _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish);
555  enum { _S_initial_map_size = 8 };
556 
557  _Deque_impl _M_impl;
558  };
559 
560  template<typename _Tp, typename _Alloc>
563  {
564  if (this->_M_impl._M_map)
565  {
566  _M_destroy_nodes(this->_M_impl._M_start._M_node,
567  this->_M_impl._M_finish._M_node + 1);
568  _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
569  }
570  }
571 
572  /**
573  * @brief Layout storage.
574  * @param __num_elements The count of T's for which to allocate space
575  * at first.
576  * @return Nothing.
577  *
578  * The initial underlying memory layout is a bit complicated...
579  */
580  template<typename _Tp, typename _Alloc>
581  void
583  _M_initialize_map(size_t __num_elements)
584  {
585  const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp))
586  + 1);
587 
588  this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size,
589  size_t(__num_nodes + 2));
590  this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size);
591 
592  // For "small" maps (needing less than _M_map_size nodes), allocation
593  // starts in the middle elements and grows outwards. So nstart may be
594  // the beginning of _M_map, but for small maps it may be as far in as
595  // _M_map+3.
596 
597  _Tp** __nstart = (this->_M_impl._M_map
598  + (this->_M_impl._M_map_size - __num_nodes) / 2);
599  _Tp** __nfinish = __nstart + __num_nodes;
600 
601  __try
602  { _M_create_nodes(__nstart, __nfinish); }
603  __catch(...)
604  {
605  _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
606  this->_M_impl._M_map = 0;
607  this->_M_impl._M_map_size = 0;
608  __throw_exception_again;
609  }
610 
611  this->_M_impl._M_start._M_set_node(__nstart);
612  this->_M_impl._M_finish._M_set_node(__nfinish - 1);
613  this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first;
614  this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first
615  + __num_elements
616  % __deque_buf_size(sizeof(_Tp)));
617  }
618 
619  template<typename _Tp, typename _Alloc>
620  void
622  _M_create_nodes(_Tp** __nstart, _Tp** __nfinish)
623  {
624  _Tp** __cur;
625  __try
626  {
627  for (__cur = __nstart; __cur < __nfinish; ++__cur)
628  *__cur = this->_M_allocate_node();
629  }
630  __catch(...)
631  {
632  _M_destroy_nodes(__nstart, __cur);
633  __throw_exception_again;
634  }
635  }
636 
637  template<typename _Tp, typename _Alloc>
638  void
639  _Deque_base<_Tp, _Alloc>::
640  _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish)
641  {
642  for (_Tp** __n = __nstart; __n < __nfinish; ++__n)
643  _M_deallocate_node(*__n);
644  }
645 
646  /**
647  * @brief A standard container using fixed-size memory allocation and
648  * constant-time manipulation of elements at either end.
649  *
650  * @ingroup sequences
651  *
652  * Meets the requirements of a <a href="tables.html#65">container</a>, a
653  * <a href="tables.html#66">reversible container</a>, and a
654  * <a href="tables.html#67">sequence</a>, including the
655  * <a href="tables.html#68">optional sequence requirements</a>.
656  *
657  * In previous HP/SGI versions of deque, there was an extra template
658  * parameter so users could control the node size. This extension turned
659  * out to violate the C++ standard (it can be detected using template
660  * template parameters), and it was removed.
661  *
662  * Here's how a deque<Tp> manages memory. Each deque has 4 members:
663  *
664  * - Tp** _M_map
665  * - size_t _M_map_size
666  * - iterator _M_start, _M_finish
667  *
668  * map_size is at least 8. %map is an array of map_size
669  * pointers-to-@a nodes. (The name %map has nothing to do with the
670  * std::map class, and @b nodes should not be confused with
671  * std::list's usage of @a node.)
672  *
673  * A @a node has no specific type name as such, but it is referred
674  * to as @a node in this file. It is a simple array-of-Tp. If Tp
675  * is very large, there will be one Tp element per node (i.e., an
676  * @a array of one). For non-huge Tp's, node size is inversely
677  * related to Tp size: the larger the Tp, the fewer Tp's will fit
678  * in a node. The goal here is to keep the total size of a node
679  * relatively small and constant over different Tp's, to improve
680  * allocator efficiency.
681  *
682  * Not every pointer in the %map array will point to a node. If
683  * the initial number of elements in the deque is small, the
684  * /middle/ %map pointers will be valid, and the ones at the edges
685  * will be unused. This same situation will arise as the %map
686  * grows: available %map pointers, if any, will be on the ends. As
687  * new nodes are created, only a subset of the %map's pointers need
688  * to be copied @a outward.
689  *
690  * Class invariants:
691  * - For any nonsingular iterator i:
692  * - i.node points to a member of the %map array. (Yes, you read that
693  * correctly: i.node does not actually point to a node.) The member of
694  * the %map array is what actually points to the node.
695  * - i.first == *(i.node) (This points to the node (first Tp element).)
696  * - i.last == i.first + node_size
697  * - i.cur is a pointer in the range [i.first, i.last). NOTE:
698  * the implication of this is that i.cur is always a dereferenceable
699  * pointer, even if i is a past-the-end iterator.
700  * - Start and Finish are always nonsingular iterators. NOTE: this
701  * means that an empty deque must have one node, a deque with <N
702  * elements (where N is the node buffer size) must have one node, a
703  * deque with N through (2N-1) elements must have two nodes, etc.
704  * - For every node other than start.node and finish.node, every
705  * element in the node is an initialized object. If start.node ==
706  * finish.node, then [start.cur, finish.cur) are initialized
707  * objects, and the elements outside that range are uninitialized
708  * storage. Otherwise, [start.cur, start.last) and [finish.first,
709  * finish.cur) are initialized objects, and [start.first, start.cur)
710  * and [finish.cur, finish.last) are uninitialized storage.
711  * - [%map, %map + map_size) is a valid, non-empty range.
712  * - [start.node, finish.node] is a valid range contained within
713  * [%map, %map + map_size).
714  * - A pointer in the range [%map, %map + map_size) points to an allocated
715  * node if and only if the pointer is in the range
716  * [start.node, finish.node].
717  *
718  * Here's the magic: nothing in deque is @b aware of the discontiguous
719  * storage!
720  *
721  * The memory setup and layout occurs in the parent, _Base, and the iterator
722  * class is entirely responsible for @a leaping from one node to the next.
723  * All the implementation routines for deque itself work only through the
724  * start and finish iterators. This keeps the routines simple and sane,
725  * and we can use other standard algorithms as well.
726  */
727  template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
728  class deque : protected _Deque_base<_Tp, _Alloc>
729  {
730  // concept requirements
731  typedef typename _Alloc::value_type _Alloc_value_type;
732  __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
733  __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
734 
736  typedef typename _Base::_Tp_alloc_type _Tp_alloc_type;
737 
738  public:
739  typedef _Tp value_type;
740  typedef typename _Tp_alloc_type::pointer pointer;
741  typedef typename _Tp_alloc_type::const_pointer const_pointer;
742  typedef typename _Tp_alloc_type::reference reference;
743  typedef typename _Tp_alloc_type::const_reference const_reference;
744  typedef typename _Base::iterator iterator;
745  typedef typename _Base::const_iterator const_iterator;
748  typedef size_t size_type;
749  typedef ptrdiff_t difference_type;
750  typedef _Alloc allocator_type;
751 
752  protected:
753  typedef pointer* _Map_pointer;
754 
755  static size_t _S_buffer_size()
756  { return __deque_buf_size(sizeof(_Tp)); }
757 
758  // Functions controlling memory layout, and nothing else.
760  using _Base::_M_create_nodes;
761  using _Base::_M_destroy_nodes;
762  using _Base::_M_allocate_node;
763  using _Base::_M_deallocate_node;
764  using _Base::_M_allocate_map;
765  using _Base::_M_deallocate_map;
766  using _Base::_M_get_Tp_allocator;
767 
768  /**
769  * A total of four data members accumulated down the hierarchy.
770  * May be accessed via _M_impl.*
771  */
772  using _Base::_M_impl;
773 
774  public:
775  // [23.2.1.1] construct/copy/destroy
776  // (assign() and get_allocator() are also listed in this section)
777  /**
778  * @brief Default constructor creates no elements.
779  */
781  : _Base() { }
782 
783  /**
784  * @brief Creates a %deque with no elements.
785  * @param __a An allocator object.
786  */
787  explicit
788  deque(const allocator_type& __a)
789  : _Base(__a, 0) { }
790 
791 #ifdef __GXX_EXPERIMENTAL_CXX0X__
792  /**
793  * @brief Creates a %deque with default constructed elements.
794  * @param __n The number of elements to initially create.
795  *
796  * This constructor fills the %deque with @a n default
797  * constructed elements.
798  */
799  explicit
800  deque(size_type __n)
801  : _Base(__n)
802  { _M_default_initialize(); }
803 
804  /**
805  * @brief Creates a %deque with copies of an exemplar element.
806  * @param __n The number of elements to initially create.
807  * @param __value An element to copy.
808  * @param __a An allocator.
809  *
810  * This constructor fills the %deque with @a __n copies of @a __value.
811  */
812  deque(size_type __n, const value_type& __value,
813  const allocator_type& __a = allocator_type())
814  : _Base(__a, __n)
815  { _M_fill_initialize(__value); }
816 #else
817  /**
818  * @brief Creates a %deque with copies of an exemplar element.
819  * @param __n The number of elements to initially create.
820  * @param __value An element to copy.
821  * @param __a An allocator.
822  *
823  * This constructor fills the %deque with @a __n copies of @a __value.
824  */
825  explicit
826  deque(size_type __n, const value_type& __value = value_type(),
827  const allocator_type& __a = allocator_type())
828  : _Base(__a, __n)
829  { _M_fill_initialize(__value); }
830 #endif
831 
832  /**
833  * @brief %Deque copy constructor.
834  * @param __x A %deque of identical element and allocator types.
835  *
836  * The newly-created %deque uses a copy of the allocation object used
837  * by @a __x.
838  */
839  deque(const deque& __x)
840  : _Base(__x._M_get_Tp_allocator(), __x.size())
841  { std::__uninitialized_copy_a(__x.begin(), __x.end(),
842  this->_M_impl._M_start,
843  _M_get_Tp_allocator()); }
844 
845 #ifdef __GXX_EXPERIMENTAL_CXX0X__
846  /**
847  * @brief %Deque move constructor.
848  * @param __x A %deque of identical element and allocator types.
849  *
850  * The newly-created %deque contains the exact contents of @a __x.
851  * The contents of @a __x are a valid, but unspecified %deque.
852  */
853  deque(deque&& __x)
854  : _Base(std::move(__x)) { }
855 
856  /**
857  * @brief Builds a %deque from an initializer list.
858  * @param __l An initializer_list.
859  * @param __a An allocator object.
860  *
861  * Create a %deque consisting of copies of the elements in the
862  * initializer_list @a __l.
863  *
864  * This will call the element type's copy constructor N times
865  * (where N is __l.size()) and do no memory reallocation.
866  */
868  const allocator_type& __a = allocator_type())
869  : _Base(__a)
870  {
871  _M_range_initialize(__l.begin(), __l.end(),
873  }
874 #endif
875 
876  /**
877  * @brief Builds a %deque from a range.
878  * @param __first An input iterator.
879  * @param __last An input iterator.
880  * @param __a An allocator object.
881  *
882  * Create a %deque consisting of copies of the elements from [__first,
883  * __last).
884  *
885  * If the iterators are forward, bidirectional, or random-access, then
886  * this will call the elements' copy constructor N times (where N is
887  * distance(__first,__last)) and do no memory reallocation. But if only
888  * input iterators are used, then this will do at most 2N calls to the
889  * copy constructor, and logN memory reallocations.
890  */
891  template<typename _InputIterator>
892  deque(_InputIterator __first, _InputIterator __last,
893  const allocator_type& __a = allocator_type())
894  : _Base(__a)
895  {
896  // Check whether it's an integral type. If so, it's not an iterator.
897  typedef typename std::__is_integer<_InputIterator>::__type _Integral;
898  _M_initialize_dispatch(__first, __last, _Integral());
899  }
900 
901  /**
902  * The dtor only erases the elements, and note that if the elements
903  * themselves are pointers, the pointed-to memory is not touched in any
904  * way. Managing the pointer is the user's responsibility.
905  */
906  ~deque() _GLIBCXX_NOEXCEPT
907  { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); }
908 
909  /**
910  * @brief %Deque assignment operator.
911  * @param __x A %deque of identical element and allocator types.
912  *
913  * All the elements of @a x are copied, but unlike the copy constructor,
914  * the allocator object is not copied.
915  */
916  deque&
917  operator=(const deque& __x);
918 
919 #ifdef __GXX_EXPERIMENTAL_CXX0X__
920  /**
921  * @brief %Deque move assignment operator.
922  * @param __x A %deque of identical element and allocator types.
923  *
924  * The contents of @a __x are moved into this deque (without copying).
925  * @a __x is a valid, but unspecified %deque.
926  */
927  deque&
929  {
930  // NB: DR 1204.
931  // NB: DR 675.
932  this->clear();
933  this->swap(__x);
934  return *this;
935  }
936 
937  /**
938  * @brief Assigns an initializer list to a %deque.
939  * @param __l An initializer_list.
940  *
941  * This function fills a %deque with copies of the elements in the
942  * initializer_list @a __l.
943  *
944  * Note that the assignment completely changes the %deque and that the
945  * resulting %deque's size is the same as the number of elements
946  * assigned. Old data may be lost.
947  */
948  deque&
950  {
951  this->assign(__l.begin(), __l.end());
952  return *this;
953  }
954 #endif
955 
956  /**
957  * @brief Assigns a given value to a %deque.
958  * @param __n Number of elements to be assigned.
959  * @param __val Value to be assigned.
960  *
961  * This function fills a %deque with @a n copies of the given
962  * value. Note that the assignment completely changes the
963  * %deque and that the resulting %deque's size is the same as
964  * the number of elements assigned. Old data may be lost.
965  */
966  void
967  assign(size_type __n, const value_type& __val)
968  { _M_fill_assign(__n, __val); }
969 
970  /**
971  * @brief Assigns a range to a %deque.
972  * @param __first An input iterator.
973  * @param __last An input iterator.
974  *
975  * This function fills a %deque with copies of the elements in the
976  * range [__first,__last).
977  *
978  * Note that the assignment completely changes the %deque and that the
979  * resulting %deque's size is the same as the number of elements
980  * assigned. Old data may be lost.
981  */
982  template<typename _InputIterator>
983  void
984  assign(_InputIterator __first, _InputIterator __last)
985  {
986  typedef typename std::__is_integer<_InputIterator>::__type _Integral;
987  _M_assign_dispatch(__first, __last, _Integral());
988  }
989 
990 #ifdef __GXX_EXPERIMENTAL_CXX0X__
991  /**
992  * @brief Assigns an initializer list to a %deque.
993  * @param __l An initializer_list.
994  *
995  * This function fills a %deque with copies of the elements in the
996  * initializer_list @a __l.
997  *
998  * Note that the assignment completely changes the %deque and that the
999  * resulting %deque's size is the same as the number of elements
1000  * assigned. Old data may be lost.
1001  */
1002  void
1004  { this->assign(__l.begin(), __l.end()); }
1005 #endif
1006 
1007  /// Get a copy of the memory allocation object.
1008  allocator_type
1009  get_allocator() const _GLIBCXX_NOEXCEPT
1010  { return _Base::get_allocator(); }
1011 
1012  // iterators
1013  /**
1014  * Returns a read/write iterator that points to the first element in the
1015  * %deque. Iteration is done in ordinary element order.
1016  */
1017  iterator
1018  begin() _GLIBCXX_NOEXCEPT
1019  { return this->_M_impl._M_start; }
1020 
1021  /**
1022  * Returns a read-only (constant) iterator that points to the first
1023  * element in the %deque. Iteration is done in ordinary element order.
1024  */
1025  const_iterator
1026  begin() const _GLIBCXX_NOEXCEPT
1027  { return this->_M_impl._M_start; }
1028 
1029  /**
1030  * Returns a read/write iterator that points one past the last
1031  * element in the %deque. Iteration is done in ordinary
1032  * element order.
1033  */
1034  iterator
1035  end() _GLIBCXX_NOEXCEPT
1036  { return this->_M_impl._M_finish; }
1037 
1038  /**
1039  * Returns a read-only (constant) iterator that points one past
1040  * the last element in the %deque. Iteration is done in
1041  * ordinary element order.
1042  */
1043  const_iterator
1044  end() const _GLIBCXX_NOEXCEPT
1045  { return this->_M_impl._M_finish; }
1046 
1047  /**
1048  * Returns a read/write reverse iterator that points to the
1049  * last element in the %deque. Iteration is done in reverse
1050  * element order.
1051  */
1053  rbegin() _GLIBCXX_NOEXCEPT
1054  { return reverse_iterator(this->_M_impl._M_finish); }
1055 
1056  /**
1057  * Returns a read-only (constant) reverse iterator that points
1058  * to the last element in the %deque. Iteration is done in
1059  * reverse element order.
1060  */
1061  const_reverse_iterator
1062  rbegin() const _GLIBCXX_NOEXCEPT
1063  { return const_reverse_iterator(this->_M_impl._M_finish); }
1064 
1065  /**
1066  * Returns a read/write reverse iterator that points to one
1067  * before the first element in the %deque. Iteration is done
1068  * in reverse element order.
1069  */
1071  rend() _GLIBCXX_NOEXCEPT
1072  { return reverse_iterator(this->_M_impl._M_start); }
1073 
1074  /**
1075  * Returns a read-only (constant) reverse iterator that points
1076  * to one before the first element in the %deque. Iteration is
1077  * done in reverse element order.
1078  */
1079  const_reverse_iterator
1080  rend() const _GLIBCXX_NOEXCEPT
1081  { return const_reverse_iterator(this->_M_impl._M_start); }
1082 
1083 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1084  /**
1085  * Returns a read-only (constant) iterator that points to the first
1086  * element in the %deque. Iteration is done in ordinary element order.
1087  */
1088  const_iterator
1089  cbegin() const noexcept
1090  { return this->_M_impl._M_start; }
1091 
1092  /**
1093  * Returns a read-only (constant) iterator that points one past
1094  * the last element in the %deque. Iteration is done in
1095  * ordinary element order.
1096  */
1097  const_iterator
1098  cend() const noexcept
1099  { return this->_M_impl._M_finish; }
1100 
1101  /**
1102  * Returns a read-only (constant) reverse iterator that points
1103  * to the last element in the %deque. Iteration is done in
1104  * reverse element order.
1105  */
1106  const_reverse_iterator
1107  crbegin() const noexcept
1108  { return const_reverse_iterator(this->_M_impl._M_finish); }
1109 
1110  /**
1111  * Returns a read-only (constant) reverse iterator that points
1112  * to one before the first element in the %deque. Iteration is
1113  * done in reverse element order.
1114  */
1115  const_reverse_iterator
1116  crend() const noexcept
1117  { return const_reverse_iterator(this->_M_impl._M_start); }
1118 #endif
1119 
1120  // [23.2.1.2] capacity
1121  /** Returns the number of elements in the %deque. */
1122  size_type
1123  size() const _GLIBCXX_NOEXCEPT
1124  { return this->_M_impl._M_finish - this->_M_impl._M_start; }
1125 
1126  /** Returns the size() of the largest possible %deque. */
1127  size_type
1128  max_size() const _GLIBCXX_NOEXCEPT
1129  { return _M_get_Tp_allocator().max_size(); }
1130 
1131 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1132  /**
1133  * @brief Resizes the %deque to the specified number of elements.
1134  * @param __new_size Number of elements the %deque should contain.
1135  *
1136  * This function will %resize the %deque to the specified
1137  * number of elements. If the number is smaller than the
1138  * %deque's current size the %deque is truncated, otherwise
1139  * default constructed elements are appended.
1140  */
1141  void
1142  resize(size_type __new_size)
1143  {
1144  const size_type __len = size();
1145  if (__new_size > __len)
1146  _M_default_append(__new_size - __len);
1147  else if (__new_size < __len)
1148  _M_erase_at_end(this->_M_impl._M_start
1149  + difference_type(__new_size));
1150  }
1151 
1152  /**
1153  * @brief Resizes the %deque to the specified number of elements.
1154  * @param __new_size Number of elements the %deque should contain.
1155  * @param __x Data with which new elements should be populated.
1156  *
1157  * This function will %resize the %deque to the specified
1158  * number of elements. If the number is smaller than the
1159  * %deque's current size the %deque is truncated, otherwise the
1160  * %deque is extended and new elements are populated with given
1161  * data.
1162  */
1163  void
1164  resize(size_type __new_size, const value_type& __x)
1165  {
1166  const size_type __len = size();
1167  if (__new_size > __len)
1168  insert(this->_M_impl._M_finish, __new_size - __len, __x);
1169  else if (__new_size < __len)
1170  _M_erase_at_end(this->_M_impl._M_start
1171  + difference_type(__new_size));
1172  }
1173 #else
1174  /**
1175  * @brief Resizes the %deque to the specified number of elements.
1176  * @param __new_size Number of elements the %deque should contain.
1177  * @param __x Data with which new elements should be populated.
1178  *
1179  * This function will %resize the %deque to the specified
1180  * number of elements. If the number is smaller than the
1181  * %deque's current size the %deque is truncated, otherwise the
1182  * %deque is extended and new elements are populated with given
1183  * data.
1184  */
1185  void
1186  resize(size_type __new_size, value_type __x = value_type())
1187  {
1188  const size_type __len = size();
1189  if (__new_size > __len)
1190  insert(this->_M_impl._M_finish, __new_size - __len, __x);
1191  else if (__new_size < __len)
1192  _M_erase_at_end(this->_M_impl._M_start
1193  + difference_type(__new_size));
1194  }
1195 #endif
1196 
1197 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1198  /** A non-binding request to reduce memory use. */
1199  void
1201  { _M_shrink_to_fit(); }
1202 #endif
1203 
1204  /**
1205  * Returns true if the %deque is empty. (Thus begin() would
1206  * equal end().)
1207  */
1208  bool
1209  empty() const _GLIBCXX_NOEXCEPT
1210  { return this->_M_impl._M_finish == this->_M_impl._M_start; }
1211 
1212  // element access
1213  /**
1214  * @brief Subscript access to the data contained in the %deque.
1215  * @param __n The index of the element for which data should be
1216  * accessed.
1217  * @return Read/write reference to data.
1218  *
1219  * This operator allows for easy, array-style, data access.
1220  * Note that data access with this operator is unchecked and
1221  * out_of_range lookups are not defined. (For checked lookups
1222  * see at().)
1223  */
1224  reference
1225  operator[](size_type __n)
1226  { return this->_M_impl._M_start[difference_type(__n)]; }
1227 
1228  /**
1229  * @brief Subscript access to the data contained in the %deque.
1230  * @param __n The index of the element for which data should be
1231  * accessed.
1232  * @return Read-only (constant) reference to data.
1233  *
1234  * This operator allows for easy, array-style, data access.
1235  * Note that data access with this operator is unchecked and
1236  * out_of_range lookups are not defined. (For checked lookups
1237  * see at().)
1238  */
1239  const_reference
1240  operator[](size_type __n) const
1241  { return this->_M_impl._M_start[difference_type(__n)]; }
1242 
1243  protected:
1244  /// Safety check used only from at().
1245  void
1246  _M_range_check(size_type __n) const
1247  {
1248  if (__n >= this->size())
1249  __throw_out_of_range(__N("deque::_M_range_check"));
1250  }
1251 
1252  public:
1253  /**
1254  * @brief Provides access to the data contained in the %deque.
1255  * @param __n The index of the element for which data should be
1256  * accessed.
1257  * @return Read/write reference to data.
1258  * @throw std::out_of_range If @a __n is an invalid index.
1259  *
1260  * This function provides for safer data access. The parameter
1261  * is first checked that it is in the range of the deque. The
1262  * function throws out_of_range if the check fails.
1263  */
1264  reference
1265  at(size_type __n)
1266  {
1267  _M_range_check(__n);
1268  return (*this)[__n];
1269  }
1270 
1271  /**
1272  * @brief Provides access to the data contained in the %deque.
1273  * @param __n The index of the element for which data should be
1274  * accessed.
1275  * @return Read-only (constant) reference to data.
1276  * @throw std::out_of_range If @a __n is an invalid index.
1277  *
1278  * This function provides for safer data access. The parameter is first
1279  * checked that it is in the range of the deque. The function throws
1280  * out_of_range if the check fails.
1281  */
1282  const_reference
1283  at(size_type __n) const
1284  {
1285  _M_range_check(__n);
1286  return (*this)[__n];
1287  }
1288 
1289  /**
1290  * Returns a read/write reference to the data at the first
1291  * element of the %deque.
1292  */
1293  reference
1295  { return *begin(); }
1296 
1297  /**
1298  * Returns a read-only (constant) reference to the data at the first
1299  * element of the %deque.
1300  */
1301  const_reference
1302  front() const
1303  { return *begin(); }
1304 
1305  /**
1306  * Returns a read/write reference to the data at the last element of the
1307  * %deque.
1308  */
1309  reference
1311  {
1312  iterator __tmp = end();
1313  --__tmp;
1314  return *__tmp;
1315  }
1316 
1317  /**
1318  * Returns a read-only (constant) reference to the data at the last
1319  * element of the %deque.
1320  */
1321  const_reference
1322  back() const
1323  {
1324  const_iterator __tmp = end();
1325  --__tmp;
1326  return *__tmp;
1327  }
1328 
1329  // [23.2.1.2] modifiers
1330  /**
1331  * @brief Add data to the front of the %deque.
1332  * @param __x Data to be added.
1333  *
1334  * This is a typical stack operation. The function creates an
1335  * element at the front of the %deque and assigns the given
1336  * data to it. Due to the nature of a %deque this operation
1337  * can be done in constant time.
1338  */
1339  void
1340  push_front(const value_type& __x)
1341  {
1342  if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first)
1343  {
1344  this->_M_impl.construct(this->_M_impl._M_start._M_cur - 1, __x);
1345  --this->_M_impl._M_start._M_cur;
1346  }
1347  else
1348  _M_push_front_aux(__x);
1349  }
1350 
1351 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1352  void
1353  push_front(value_type&& __x)
1354  { emplace_front(std::move(__x)); }
1355 
1356  template<typename... _Args>
1357  void
1358  emplace_front(_Args&&... __args);
1359 #endif
1360 
1361  /**
1362  * @brief Add data to the end of the %deque.
1363  * @param __x Data to be added.
1364  *
1365  * This is a typical stack operation. The function creates an
1366  * element at the end of the %deque and assigns the given data
1367  * to it. Due to the nature of a %deque this operation can be
1368  * done in constant time.
1369  */
1370  void
1371  push_back(const value_type& __x)
1372  {
1373  if (this->_M_impl._M_finish._M_cur
1374  != this->_M_impl._M_finish._M_last - 1)
1375  {
1376  this->_M_impl.construct(this->_M_impl._M_finish._M_cur, __x);
1377  ++this->_M_impl._M_finish._M_cur;
1378  }
1379  else
1380  _M_push_back_aux(__x);
1381  }
1382 
1383 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1384  void
1385  push_back(value_type&& __x)
1386  { emplace_back(std::move(__x)); }
1387 
1388  template<typename... _Args>
1389  void
1390  emplace_back(_Args&&... __args);
1391 #endif
1392 
1393  /**
1394  * @brief Removes first element.
1395  *
1396  * This is a typical stack operation. It shrinks the %deque by one.
1397  *
1398  * Note that no data is returned, and if the first element's data is
1399  * needed, it should be retrieved before pop_front() is called.
1400  */
1401  void
1403  {
1404  if (this->_M_impl._M_start._M_cur
1405  != this->_M_impl._M_start._M_last - 1)
1406  {
1407  this->_M_impl.destroy(this->_M_impl._M_start._M_cur);
1408  ++this->_M_impl._M_start._M_cur;
1409  }
1410  else
1411  _M_pop_front_aux();
1412  }
1413 
1414  /**
1415  * @brief Removes last element.
1416  *
1417  * This is a typical stack operation. It shrinks the %deque by one.
1418  *
1419  * Note that no data is returned, and if the last element's data is
1420  * needed, it should be retrieved before pop_back() is called.
1421  */
1422  void
1424  {
1425  if (this->_M_impl._M_finish._M_cur
1426  != this->_M_impl._M_finish._M_first)
1427  {
1428  --this->_M_impl._M_finish._M_cur;
1429  this->_M_impl.destroy(this->_M_impl._M_finish._M_cur);
1430  }
1431  else
1432  _M_pop_back_aux();
1433  }
1434 
1435 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1436  /**
1437  * @brief Inserts an object in %deque before specified iterator.
1438  * @param __position An iterator into the %deque.
1439  * @param __args Arguments.
1440  * @return An iterator that points to the inserted data.
1441  *
1442  * This function will insert an object of type T constructed
1443  * with T(std::forward<Args>(args)...) before the specified location.
1444  */
1445  template<typename... _Args>
1446  iterator
1447  emplace(iterator __position, _Args&&... __args);
1448 #endif
1449 
1450  /**
1451  * @brief Inserts given value into %deque before specified iterator.
1452  * @param __position An iterator into the %deque.
1453  * @param __x Data to be inserted.
1454  * @return An iterator that points to the inserted data.
1455  *
1456  * This function will insert a copy of the given value before the
1457  * specified location.
1458  */
1459  iterator
1460  insert(iterator __position, const value_type& __x);
1461 
1462 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1463  /**
1464  * @brief Inserts given rvalue into %deque before specified iterator.
1465  * @param __position An iterator into the %deque.
1466  * @param __x Data to be inserted.
1467  * @return An iterator that points to the inserted data.
1468  *
1469  * This function will insert a copy of the given rvalue before the
1470  * specified location.
1471  */
1472  iterator
1473  insert(iterator __position, value_type&& __x)
1474  { return emplace(__position, std::move(__x)); }
1475 
1476  /**
1477  * @brief Inserts an initializer list into the %deque.
1478  * @param __p An iterator into the %deque.
1479  * @param __l An initializer_list.
1480  *
1481  * This function will insert copies of the data in the
1482  * initializer_list @a __l into the %deque before the location
1483  * specified by @a __p. This is known as <em>list insert</em>.
1484  */
1485  void
1487  { this->insert(__p, __l.begin(), __l.end()); }
1488 #endif
1489 
1490  /**
1491  * @brief Inserts a number of copies of given data into the %deque.
1492  * @param __position An iterator into the %deque.
1493  * @param __n Number of elements to be inserted.
1494  * @param __x Data to be inserted.
1495  *
1496  * This function will insert a specified number of copies of the given
1497  * data before the location specified by @a __position.
1498  */
1499  void
1500  insert(iterator __position, size_type __n, const value_type& __x)
1501  { _M_fill_insert(__position, __n, __x); }
1502 
1503  /**
1504  * @brief Inserts a range into the %deque.
1505  * @param __position An iterator into the %deque.
1506  * @param __first An input iterator.
1507  * @param __last An input iterator.
1508  *
1509  * This function will insert copies of the data in the range
1510  * [__first,__last) into the %deque before the location specified
1511  * by @a __position. This is known as <em>range insert</em>.
1512  */
1513  template<typename _InputIterator>
1514  void
1515  insert(iterator __position, _InputIterator __first,
1516  _InputIterator __last)
1517  {
1518  // Check whether it's an integral type. If so, it's not an iterator.
1519  typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1520  _M_insert_dispatch(__position, __first, __last, _Integral());
1521  }
1522 
1523  /**
1524  * @brief Remove element at given position.
1525  * @param __position Iterator pointing to element to be erased.
1526  * @return An iterator pointing to the next element (or end()).
1527  *
1528  * This function will erase the element at the given position and thus
1529  * shorten the %deque by one.
1530  *
1531  * The user is cautioned that
1532  * this function only erases the element, and that if the element is
1533  * itself a pointer, the pointed-to memory is not touched in any way.
1534  * Managing the pointer is the user's responsibility.
1535  */
1536  iterator
1537  erase(iterator __position);
1538 
1539  /**
1540  * @brief Remove a range of elements.
1541  * @param __first Iterator pointing to the first element to be erased.
1542  * @param __last Iterator pointing to one past the last element to be
1543  * erased.
1544  * @return An iterator pointing to the element pointed to by @a last
1545  * prior to erasing (or end()).
1546  *
1547  * This function will erase the elements in the range
1548  * [__first,__last) and shorten the %deque accordingly.
1549  *
1550  * The user is cautioned that
1551  * this function only erases the elements, and that if the elements
1552  * themselves are pointers, the pointed-to memory is not touched in any
1553  * way. Managing the pointer is the user's responsibility.
1554  */
1555  iterator
1556  erase(iterator __first, iterator __last);
1557 
1558  /**
1559  * @brief Swaps data with another %deque.
1560  * @param __x A %deque of the same element and allocator types.
1561  *
1562  * This exchanges the elements between two deques in constant time.
1563  * (Four pointers, so it should be quite fast.)
1564  * Note that the global std::swap() function is specialized such that
1565  * std::swap(d1,d2) will feed to this function.
1566  */
1567  void
1568  swap(deque& __x)
1569  {
1570  std::swap(this->_M_impl._M_start, __x._M_impl._M_start);
1571  std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish);
1572  std::swap(this->_M_impl._M_map, __x._M_impl._M_map);
1573  std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size);
1574 
1575  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1576  // 431. Swapping containers with unequal allocators.
1577  std::__alloc_swap<_Tp_alloc_type>::_S_do_it(_M_get_Tp_allocator(),
1578  __x._M_get_Tp_allocator());
1579  }
1580 
1581  /**
1582  * Erases all the elements. Note that this function only erases the
1583  * elements, and that if the elements themselves are pointers, the
1584  * pointed-to memory is not touched in any way. Managing the pointer is
1585  * the user's responsibility.
1586  */
1587  void
1588  clear() _GLIBCXX_NOEXCEPT
1589  { _M_erase_at_end(begin()); }
1590 
1591  protected:
1592  // Internal constructor functions follow.
1593 
1594  // called by the range constructor to implement [23.1.1]/9
1595 
1596  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1597  // 438. Ambiguity in the "do the right thing" clause
1598  template<typename _Integer>
1599  void
1600  _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type)
1601  {
1602  _M_initialize_map(static_cast<size_type>(__n));
1603  _M_fill_initialize(__x);
1604  }
1605 
1606  // called by the range constructor to implement [23.1.1]/9
1607  template<typename _InputIterator>
1608  void
1609  _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
1610  __false_type)
1611  {
1612  typedef typename std::iterator_traits<_InputIterator>::
1613  iterator_category _IterCategory;
1614  _M_range_initialize(__first, __last, _IterCategory());
1615  }
1616 
1617  // called by the second initialize_dispatch above
1618  //@{
1619  /**
1620  * @brief Fills the deque with whatever is in [first,last).
1621  * @param __first An input iterator.
1622  * @param __last An input iterator.
1623  * @return Nothing.
1624  *
1625  * If the iterators are actually forward iterators (or better), then the
1626  * memory layout can be done all at once. Else we move forward using
1627  * push_back on each value from the iterator.
1628  */
1629  template<typename _InputIterator>
1630  void
1631  _M_range_initialize(_InputIterator __first, _InputIterator __last,
1633 
1634  // called by the second initialize_dispatch above
1635  template<typename _ForwardIterator>
1636  void
1637  _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
1639  //@}
1640 
1641  /**
1642  * @brief Fills the %deque with copies of value.
1643  * @param __value Initial value.
1644  * @return Nothing.
1645  * @pre _M_start and _M_finish have already been initialized,
1646  * but none of the %deque's elements have yet been constructed.
1647  *
1648  * This function is called only when the user provides an explicit size
1649  * (with or without an explicit exemplar value).
1650  */
1651  void
1652  _M_fill_initialize(const value_type& __value);
1653 
1654 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1655  // called by deque(n).
1656  void
1657  _M_default_initialize();
1658 #endif
1659 
1660  // Internal assign functions follow. The *_aux functions do the actual
1661  // assignment work for the range versions.
1662 
1663  // called by the range assign to implement [23.1.1]/9
1664 
1665  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1666  // 438. Ambiguity in the "do the right thing" clause
1667  template<typename _Integer>
1668  void
1669  _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
1670  { _M_fill_assign(__n, __val); }
1671 
1672  // called by the range assign to implement [23.1.1]/9
1673  template<typename _InputIterator>
1674  void
1675  _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
1676  __false_type)
1677  {
1678  typedef typename std::iterator_traits<_InputIterator>::
1679  iterator_category _IterCategory;
1680  _M_assign_aux(__first, __last, _IterCategory());
1681  }
1682 
1683  // called by the second assign_dispatch above
1684  template<typename _InputIterator>
1685  void
1686  _M_assign_aux(_InputIterator __first, _InputIterator __last,
1688 
1689  // called by the second assign_dispatch above
1690  template<typename _ForwardIterator>
1691  void
1692  _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
1694  {
1695  const size_type __len = std::distance(__first, __last);
1696  if (__len > size())
1697  {
1698  _ForwardIterator __mid = __first;
1699  std::advance(__mid, size());
1700  std::copy(__first, __mid, begin());
1701  insert(end(), __mid, __last);
1702  }
1703  else
1704  _M_erase_at_end(std::copy(__first, __last, begin()));
1705  }
1706 
1707  // Called by assign(n,t), and the range assign when it turns out
1708  // to be the same thing.
1709  void
1710  _M_fill_assign(size_type __n, const value_type& __val)
1711  {
1712  if (__n > size())
1713  {
1714  std::fill(begin(), end(), __val);
1715  insert(end(), __n - size(), __val);
1716  }
1717  else
1718  {
1719  _M_erase_at_end(begin() + difference_type(__n));
1720  std::fill(begin(), end(), __val);
1721  }
1722  }
1723 
1724  //@{
1725  /// Helper functions for push_* and pop_*.
1726 #ifndef __GXX_EXPERIMENTAL_CXX0X__
1727  void _M_push_back_aux(const value_type&);
1728 
1729  void _M_push_front_aux(const value_type&);
1730 #else
1731  template<typename... _Args>
1732  void _M_push_back_aux(_Args&&... __args);
1733 
1734  template<typename... _Args>
1735  void _M_push_front_aux(_Args&&... __args);
1736 #endif
1737 
1738  void _M_pop_back_aux();
1739 
1740  void _M_pop_front_aux();
1741  //@}
1742 
1743  // Internal insert functions follow. The *_aux functions do the actual
1744  // insertion work when all shortcuts fail.
1745 
1746  // called by the range insert to implement [23.1.1]/9
1747 
1748  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1749  // 438. Ambiguity in the "do the right thing" clause
1750  template<typename _Integer>
1751  void
1752  _M_insert_dispatch(iterator __pos,
1753  _Integer __n, _Integer __x, __true_type)
1754  { _M_fill_insert(__pos, __n, __x); }
1755 
1756  // called by the range insert to implement [23.1.1]/9
1757  template<typename _InputIterator>
1758  void
1759  _M_insert_dispatch(iterator __pos,
1760  _InputIterator __first, _InputIterator __last,
1761  __false_type)
1762  {
1763  typedef typename std::iterator_traits<_InputIterator>::
1764  iterator_category _IterCategory;
1765  _M_range_insert_aux(__pos, __first, __last, _IterCategory());
1766  }
1767 
1768  // called by the second insert_dispatch above
1769  template<typename _InputIterator>
1770  void
1771  _M_range_insert_aux(iterator __pos, _InputIterator __first,
1772  _InputIterator __last, std::input_iterator_tag);
1773 
1774  // called by the second insert_dispatch above
1775  template<typename _ForwardIterator>
1776  void
1777  _M_range_insert_aux(iterator __pos, _ForwardIterator __first,
1778  _ForwardIterator __last, std::forward_iterator_tag);
1779 
1780  // Called by insert(p,n,x), and the range insert when it turns out to be
1781  // the same thing. Can use fill functions in optimal situations,
1782  // otherwise passes off to insert_aux(p,n,x).
1783  void
1784  _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);
1785 
1786  // called by insert(p,x)
1787 #ifndef __GXX_EXPERIMENTAL_CXX0X__
1788  iterator
1789  _M_insert_aux(iterator __pos, const value_type& __x);
1790 #else
1791  template<typename... _Args>
1792  iterator
1793  _M_insert_aux(iterator __pos, _Args&&... __args);
1794 #endif
1795 
1796  // called by insert(p,n,x) via fill_insert
1797  void
1798  _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);
1799 
1800  // called by range_insert_aux for forward iterators
1801  template<typename _ForwardIterator>
1802  void
1803  _M_insert_aux(iterator __pos,
1804  _ForwardIterator __first, _ForwardIterator __last,
1805  size_type __n);
1806 
1807 
1808  // Internal erase functions follow.
1809 
1810  void
1811  _M_destroy_data_aux(iterator __first, iterator __last);
1812 
1813  // Called by ~deque().
1814  // NB: Doesn't deallocate the nodes.
1815  template<typename _Alloc1>
1816  void
1817  _M_destroy_data(iterator __first, iterator __last, const _Alloc1&)
1818  { _M_destroy_data_aux(__first, __last); }
1819 
1820  void
1821  _M_destroy_data(iterator __first, iterator __last,
1822  const std::allocator<_Tp>&)
1823  {
1824  if (!__has_trivial_destructor(value_type))
1825  _M_destroy_data_aux(__first, __last);
1826  }
1827 
1828  // Called by erase(q1, q2).
1829  void
1830  _M_erase_at_begin(iterator __pos)
1831  {
1832  _M_destroy_data(begin(), __pos, _M_get_Tp_allocator());
1833  _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node);
1834  this->_M_impl._M_start = __pos;
1835  }
1836 
1837  // Called by erase(q1, q2), resize(), clear(), _M_assign_aux,
1838  // _M_fill_assign, operator=.
1839  void
1840  _M_erase_at_end(iterator __pos)
1841  {
1842  _M_destroy_data(__pos, end(), _M_get_Tp_allocator());
1843  _M_destroy_nodes(__pos._M_node + 1,
1844  this->_M_impl._M_finish._M_node + 1);
1845  this->_M_impl._M_finish = __pos;
1846  }
1847 
1848 #ifdef __GXX_EXPERIMENTAL_CXX0X__
1849  // Called by resize(sz).
1850  void
1851  _M_default_append(size_type __n);
1852 
1853  bool
1854  _M_shrink_to_fit();
1855 #endif
1856 
1857  //@{
1858  /// Memory-handling helpers for the previous internal insert functions.
1859  iterator
1861  {
1862  const size_type __vacancies = this->_M_impl._M_start._M_cur
1863  - this->_M_impl._M_start._M_first;
1864  if (__n > __vacancies)
1865  _M_new_elements_at_front(__n - __vacancies);
1866  return this->_M_impl._M_start - difference_type(__n);
1867  }
1868 
1869  iterator
1871  {
1872  const size_type __vacancies = (this->_M_impl._M_finish._M_last
1873  - this->_M_impl._M_finish._M_cur) - 1;
1874  if (__n > __vacancies)
1875  _M_new_elements_at_back(__n - __vacancies);
1876  return this->_M_impl._M_finish + difference_type(__n);
1877  }
1878 
1879  void
1880  _M_new_elements_at_front(size_type __new_elements);
1881 
1882  void
1883  _M_new_elements_at_back(size_type __new_elements);
1884  //@}
1885 
1886 
1887  //@{
1888  /**
1889  * @brief Memory-handling helpers for the major %map.
1890  *
1891  * Makes sure the _M_map has space for new nodes. Does not
1892  * actually add the nodes. Can invalidate _M_map pointers.
1893  * (And consequently, %deque iterators.)
1894  */
1895  void
1896  _M_reserve_map_at_back(size_type __nodes_to_add = 1)
1897  {
1898  if (__nodes_to_add + 1 > this->_M_impl._M_map_size
1899  - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map))
1900  _M_reallocate_map(__nodes_to_add, false);
1901  }
1902 
1903  void
1904  _M_reserve_map_at_front(size_type __nodes_to_add = 1)
1905  {
1906  if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node
1907  - this->_M_impl._M_map))
1908  _M_reallocate_map(__nodes_to_add, true);
1909  }
1910 
1911  void
1912  _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);
1913  //@}
1914  };
1915 
1916 
1917  /**
1918  * @brief Deque equality comparison.
1919  * @param __x A %deque.
1920  * @param __y A %deque of the same type as @a __x.
1921  * @return True iff the size and elements of the deques are equal.
1922  *
1923  * This is an equivalence relation. It is linear in the size of the
1924  * deques. Deques are considered equivalent if their sizes are equal,
1925  * and if corresponding elements compare equal.
1926  */
1927  template<typename _Tp, typename _Alloc>
1928  inline bool
1929  operator==(const deque<_Tp, _Alloc>& __x,
1930  const deque<_Tp, _Alloc>& __y)
1931  { return __x.size() == __y.size()
1932  && std::equal(__x.begin(), __x.end(), __y.begin()); }
1933 
1934  /**
1935  * @brief Deque ordering relation.
1936  * @param __x A %deque.
1937  * @param __y A %deque of the same type as @a __x.
1938  * @return True iff @a x is lexicographically less than @a __y.
1939  *
1940  * This is a total ordering relation. It is linear in the size of the
1941  * deques. The elements must be comparable with @c <.
1942  *
1943  * See std::lexicographical_compare() for how the determination is made.
1944  */
1945  template<typename _Tp, typename _Alloc>
1946  inline bool
1947  operator<(const deque<_Tp, _Alloc>& __x,
1948  const deque<_Tp, _Alloc>& __y)
1949  { return std::lexicographical_compare(__x.begin(), __x.end(),
1950  __y.begin(), __y.end()); }
1951 
1952  /// Based on operator==
1953  template<typename _Tp, typename _Alloc>
1954  inline bool
1955  operator!=(const deque<_Tp, _Alloc>& __x,
1956  const deque<_Tp, _Alloc>& __y)
1957  { return !(__x == __y); }
1958 
1959  /// Based on operator<
1960  template<typename _Tp, typename _Alloc>
1961  inline bool
1962  operator>(const deque<_Tp, _Alloc>& __x,
1963  const deque<_Tp, _Alloc>& __y)
1964  { return __y < __x; }
1965 
1966  /// Based on operator<
1967  template<typename _Tp, typename _Alloc>
1968  inline bool
1969  operator<=(const deque<_Tp, _Alloc>& __x,
1970  const deque<_Tp, _Alloc>& __y)
1971  { return !(__y < __x); }
1972 
1973  /// Based on operator<
1974  template<typename _Tp, typename _Alloc>
1975  inline bool
1976  operator>=(const deque<_Tp, _Alloc>& __x,
1977  const deque<_Tp, _Alloc>& __y)
1978  { return !(__x < __y); }
1979 
1980  /// See std::deque::swap().
1981  template<typename _Tp, typename _Alloc>
1982  inline void
1984  { __x.swap(__y); }
1985 
1986 #undef _GLIBCXX_DEQUE_BUF_SIZE
1987 
1988 _GLIBCXX_END_NAMESPACE_CONTAINER
1989 } // namespace std
1990 
1991 #endif /* _STL_DEQUE_H */