1 // Deque implementation -*- C++ -*- 2 3 // Copyright (C) 2001-2019 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /* 26 * 27 * Copyright (c) 1994 28 * Hewlett-Packard Company 29 * 30 * Permission to use, copy, modify, distribute and sell this software 31 * and its documentation for any purpose is hereby granted without fee, 32 * provided that the above copyright notice appear in all copies and 33 * that both that copyright notice and this permission notice appear 34 * in supporting documentation. Hewlett-Packard Company makes no 35 * representations about the suitability of this software for any 36 * purpose. It is provided "as is" without express or implied warranty. 37 * 38 * 39 * Copyright (c) 1997 40 * Silicon Graphics Computer Systems, Inc. 41 * 42 * Permission to use, copy, modify, distribute and sell this software 43 * and its documentation for any purpose is hereby granted without fee, 44 * provided that the above copyright notice appear in all copies and 45 * that both that copyright notice and this permission notice appear 46 * in supporting documentation. Silicon Graphics makes no 47 * representations about the suitability of this software for any 48 * purpose. It is provided "as is" without express or implied warranty. 49 */ 50 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} 54 */ 55 56 #ifndef _STL_DEQUE_H 57 #define _STL_DEQUE_H 1 58 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> 64 #include <bits/stl_uninitialized.h> // for __is_bitwise_relocatable 65 #endif 66 67 #include <debug/assertions.h> 68 69 namespace std _GLIBCXX_VISIBILITY(default) 70 { 71 _GLIBCXX_BEGIN_NAMESPACE_VERSION 72 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER 73 74 /** 75 * @brief This function controls the size of memory nodes. 76 * @param __size The size of an element. 77 * @return The number (not byte size) of elements per node. 78 * 79 * This function started off as a compiler kludge from SGI, but 80 * seems to be a useful wrapper around a repeated constant 81 * expression. The @b 512 is tunable (and no other code needs to 82 * change), but no investigation has been done since inheriting the 83 * SGI code. Touch _GLIBCXX_DEQUE_BUF_SIZE only if you know what 84 * you are doing, however: changing it breaks the binary 85 * compatibility!! 86 */ 87 88 #ifndef _GLIBCXX_DEQUE_BUF_SIZE 89 #define _GLIBCXX_DEQUE_BUF_SIZE 512 90 #endif 91 92 _GLIBCXX_CONSTEXPR inline size_t 93 __deque_buf_size(size_t __size) 94 { return (__size < _GLIBCXX_DEQUE_BUF_SIZE 95 ? size_t(_GLIBCXX_DEQUE_BUF_SIZE / __size) : size_t(1)); } 96 97 98 /** 99 * @brief A deque::iterator. 100 * 101 * Quite a bit of intelligence here. Much of the functionality of 102 * deque is actually passed off to this class. A deque holds two 103 * of these internally, marking its valid range. Access to 104 * elements is done as offsets of either of those two, relying on 105 * operator overloading in this class. 106 * 107 * All the functions are op overloads except for _M_set_node. 108 */ 109 template<typename _Tp, typename _Ref, typename _Ptr> 110 struct _Deque_iterator 111 { 112 #if __cplusplus < 201103L 113 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator; 114 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator; 115 typedef _Tp* _Elt_pointer; 116 typedef _Tp** _Map_pointer; 117 #else 118 private: 119 template<typename _Up> 120 using __ptr_to = typename pointer_traits<_Ptr>::template rebind<_Up>; 121 template<typename _CvTp> 122 using __iter = _Deque_iterator<_Tp, _CvTp&, __ptr_to<_CvTp>>; 123 public: 124 typedef __iter<_Tp> iterator; 125 typedef __iter<const _Tp> const_iterator; 126 typedef __ptr_to<_Tp> _Elt_pointer; 127 typedef __ptr_to<_Elt_pointer> _Map_pointer; 128 #endif 129 130 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 131 { return __deque_buf_size(sizeof(_Tp)); } 132 133 typedef std::random_access_iterator_tag iterator_category; 134 typedef _Tp value_type; 135 typedef _Ptr pointer; 136 typedef _Ref reference; 137 typedef size_t size_type; 138 typedef ptrdiff_t difference_type; 139 typedef _Deque_iterator _Self; 140 141 _Elt_pointer _M_cur; 142 _Elt_pointer _M_first; 143 _Elt_pointer _M_last; 144 _Map_pointer _M_node; 145 146 _Deque_iterator(_Elt_pointer __x, _Map_pointer __y) _GLIBCXX_NOEXCEPT 147 : _M_cur(__x), _M_first(*__y), 148 _M_last(*__y + _S_buffer_size()), _M_node(__y) { } 149 150 _Deque_iterator() _GLIBCXX_NOEXCEPT 151 : _M_cur(), _M_first(), _M_last(), _M_node() { } 152 153 #if __cplusplus < 201103L 154 // Conversion from iterator to const_iterator. 155 _Deque_iterator(const iterator& __x) _GLIBCXX_NOEXCEPT 156 : _M_cur(__x._M_cur), _M_first(__x._M_first), 157 _M_last(__x._M_last), _M_node(__x._M_node) { } 158 #else 159 // Conversion from iterator to const_iterator. 160 template<typename _Iter, 161 typename = _Require<is_same<_Self, const_iterator>, 162 is_same<_Iter, iterator>>> 163 _Deque_iterator(const _Iter& __x) noexcept 164 : _M_cur(__x._M_cur), _M_first(__x._M_first), 165 _M_last(__x._M_last), _M_node(__x._M_node) { } 166 167 _Deque_iterator(const _Deque_iterator& __x) noexcept 168 : _M_cur(__x._M_cur), _M_first(__x._M_first), 169 _M_last(__x._M_last), _M_node(__x._M_node) { } 170 171 _Deque_iterator& operator=(const _Deque_iterator&) = default; 172 #endif 173 174 iterator 175 _M_const_cast() const _GLIBCXX_NOEXCEPT 176 { return iterator(_M_cur, _M_node); } 177 178 reference 179 operator*() const _GLIBCXX_NOEXCEPT 180 { return *_M_cur; } 181 182 pointer 183 operator->() const _GLIBCXX_NOEXCEPT 184 { return _M_cur; } 185 186 _Self& 187 operator++() _GLIBCXX_NOEXCEPT 188 { 189 ++_M_cur; 190 if (_M_cur == _M_last) 191 { 192 _M_set_node(_M_node + 1); 193 _M_cur = _M_first; 194 } 195 return *this; 196 } 197 198 _Self 199 operator++(int) _GLIBCXX_NOEXCEPT 200 { 201 _Self __tmp = *this; 202 ++*this; 203 return __tmp; 204 } 205 206 _Self& 207 operator--() _GLIBCXX_NOEXCEPT 208 { 209 if (_M_cur == _M_first) 210 { 211 _M_set_node(_M_node - 1); 212 _M_cur = _M_last; 213 } 214 --_M_cur; 215 return *this; 216 } 217 218 _Self 219 operator--(int) _GLIBCXX_NOEXCEPT 220 { 221 _Self __tmp = *this; 222 --*this; 223 return __tmp; 224 } 225 226 _Self& 227 operator+=(difference_type __n) _GLIBCXX_NOEXCEPT 228 { 229 const difference_type __offset = __n + (_M_cur - _M_first); 230 if (__offset >= 0 && __offset < difference_type(_S_buffer_size())) 231 _M_cur += __n; 232 else 233 { 234 const difference_type __node_offset = 235 __offset > 0 ? __offset / difference_type(_S_buffer_size()) 236 : -difference_type((-__offset - 1) 237 / _S_buffer_size()) - 1; 238 _M_set_node(_M_node + __node_offset); 239 _M_cur = _M_first + (__offset - __node_offset 240 * difference_type(_S_buffer_size())); 241 } 242 return *this; 243 } 244 245 _Self 246 operator+(difference_type __n) const _GLIBCXX_NOEXCEPT 247 { 248 _Self __tmp = *this; 249 return __tmp += __n; 250 } 251 252 _Self& 253 operator-=(difference_type __n) _GLIBCXX_NOEXCEPT 254 { return *this += -__n; } 255 256 _Self 257 operator-(difference_type __n) const _GLIBCXX_NOEXCEPT 258 { 259 _Self __tmp = *this; 260 return __tmp -= __n; 261 } 262 263 reference 264 operator[](difference_type __n) const _GLIBCXX_NOEXCEPT 265 { return *(*this + __n); } 266 267 /** 268 * Prepares to traverse new_node. Sets everything except 269 * _M_cur, which should therefore be set by the caller 270 * immediately afterwards, based on _M_first and _M_last. 271 */ 272 void 273 _M_set_node(_Map_pointer __new_node) _GLIBCXX_NOEXCEPT 274 { 275 _M_node = __new_node; 276 _M_first = *__new_node; 277 _M_last = _M_first + difference_type(_S_buffer_size()); 278 } 279 }; 280 281 // Note: we also provide overloads whose operands are of the same type in 282 // order to avoid ambiguous overload resolution when std::rel_ops operators 283 // are in scope (for additional details, see libstdc++/3628) 284 template<typename _Tp, typename _Ref, typename _Ptr> 285 inline bool 286 operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 287 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 288 { return __x._M_cur == __y._M_cur; } 289 290 template<typename _Tp, typename _RefL, typename _PtrL, 291 typename _RefR, typename _PtrR> 292 inline bool 293 operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 294 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 295 { return __x._M_cur == __y._M_cur; } 296 297 template<typename _Tp, typename _Ref, typename _Ptr> 298 inline bool 299 operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 300 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 301 { return !(__x == __y); } 302 303 template<typename _Tp, typename _RefL, typename _PtrL, 304 typename _RefR, typename _PtrR> 305 inline bool 306 operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 307 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 308 { return !(__x == __y); } 309 310 template<typename _Tp, typename _Ref, typename _Ptr> 311 inline bool 312 operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 313 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 314 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 315 : (__x._M_node < __y._M_node); } 316 317 template<typename _Tp, typename _RefL, typename _PtrL, 318 typename _RefR, typename _PtrR> 319 inline bool 320 operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 321 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 322 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 323 : (__x._M_node < __y._M_node); } 324 325 template<typename _Tp, typename _Ref, typename _Ptr> 326 inline bool 327 operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 328 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 329 { return __y < __x; } 330 331 template<typename _Tp, typename _RefL, typename _PtrL, 332 typename _RefR, typename _PtrR> 333 inline bool 334 operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 335 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 336 { return __y < __x; } 337 338 template<typename _Tp, typename _Ref, typename _Ptr> 339 inline bool 340 operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 341 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 342 { return !(__y < __x); } 343 344 template<typename _Tp, typename _RefL, typename _PtrL, 345 typename _RefR, typename _PtrR> 346 inline bool 347 operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 348 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 349 { return !(__y < __x); } 350 351 template<typename _Tp, typename _Ref, typename _Ptr> 352 inline bool 353 operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 354 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 355 { return !(__x < __y); } 356 357 template<typename _Tp, typename _RefL, typename _PtrL, 358 typename _RefR, typename _PtrR> 359 inline bool 360 operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 361 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 362 { return !(__x < __y); } 363 364 // _GLIBCXX_RESOLVE_LIB_DEFECTS 365 // According to the resolution of DR179 not only the various comparison 366 // operators but also operator- must accept mixed iterator/const_iterator 367 // parameters. 368 template<typename _Tp, typename _Ref, typename _Ptr> 369 inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 370 operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 371 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 372 { 373 return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 374 (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size()) 375 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 376 + (__y._M_last - __y._M_cur); 377 } 378 379 template<typename _Tp, typename _RefL, typename _PtrL, 380 typename _RefR, typename _PtrR> 381 inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 382 operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 383 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 384 { 385 return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 386 (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size()) 387 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 388 + (__y._M_last - __y._M_cur); 389 } 390 391 template<typename _Tp, typename _Ref, typename _Ptr> 392 inline _Deque_iterator<_Tp, _Ref, _Ptr> 393 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x) 394 _GLIBCXX_NOEXCEPT 395 { return __x + __n; } 396 397 template<typename _Tp> 398 void 399 fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>&, 400 const _Deque_iterator<_Tp, _Tp&, _Tp*>&, const _Tp&); 401 402 template<typename _Tp> 403 _Deque_iterator<_Tp, _Tp&, _Tp*> 404 copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 405 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 406 _Deque_iterator<_Tp, _Tp&, _Tp*>); 407 408 template<typename _Tp> 409 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 410 copy(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 411 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 412 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 413 { return std::copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 414 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 415 __result); } 416 417 template<typename _Tp> 418 _Deque_iterator<_Tp, _Tp&, _Tp*> 419 copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 420 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 421 _Deque_iterator<_Tp, _Tp&, _Tp*>); 422 423 template<typename _Tp> 424 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 425 copy_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 426 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 427 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 428 { return std::copy_backward(_Deque_iterator<_Tp, 429 const _Tp&, const _Tp*>(__first), 430 _Deque_iterator<_Tp, 431 const _Tp&, const _Tp*>(__last), 432 __result); } 433 434 #if __cplusplus >= 201103L 435 template<typename _Tp> 436 _Deque_iterator<_Tp, _Tp&, _Tp*> 437 move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 438 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 439 _Deque_iterator<_Tp, _Tp&, _Tp*>); 440 441 template<typename _Tp> 442 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 443 move(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 444 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 445 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 446 { return std::move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 447 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 448 __result); } 449 450 template<typename _Tp> 451 _Deque_iterator<_Tp, _Tp&, _Tp*> 452 move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 453 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 454 _Deque_iterator<_Tp, _Tp&, _Tp*>); 455 456 template<typename _Tp> 457 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 458 move_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 459 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 460 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 461 { return std::move_backward(_Deque_iterator<_Tp, 462 const _Tp&, const _Tp*>(__first), 463 _Deque_iterator<_Tp, 464 const _Tp&, const _Tp*>(__last), 465 __result); } 466 #endif 467 468 /** 469 * Deque base class. This class provides the unified face for %deque's 470 * allocation. This class's constructor and destructor allocate and 471 * deallocate (but do not initialize) storage. This makes %exception 472 * safety easier. 473 * 474 * Nothing in this class ever constructs or destroys an actual Tp element. 475 * (Deque handles that itself.) Only/All memory management is performed 476 * here. 477 */ 478 template<typename _Tp, typename _Alloc> 479 class _Deque_base 480 { 481 protected: 482 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template 483 rebind<_Tp>::other _Tp_alloc_type; 484 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits; 485 486 #if __cplusplus < 201103L 487 typedef _Tp* _Ptr; 488 typedef const _Tp* _Ptr_const; 489 #else 490 typedef typename _Alloc_traits::pointer _Ptr; 491 typedef typename _Alloc_traits::const_pointer _Ptr_const; 492 #endif 493 494 typedef typename _Alloc_traits::template rebind<_Ptr>::other 495 _Map_alloc_type; 496 typedef __gnu_cxx::__alloc_traits<_Map_alloc_type> _Map_alloc_traits; 497 498 public: 499 typedef _Alloc allocator_type; 500 501 allocator_type 502 get_allocator() const _GLIBCXX_NOEXCEPT 503 { return allocator_type(_M_get_Tp_allocator()); } 504 505 typedef _Deque_iterator<_Tp, _Tp&, _Ptr> iterator; 506 typedef _Deque_iterator<_Tp, const _Tp&, _Ptr_const> const_iterator; 507 508 _Deque_base() 509 : _M_impl() 510 { _M_initialize_map(0); } 511 512 _Deque_base(size_t __num_elements) 513 : _M_impl() 514 { _M_initialize_map(__num_elements); } 515 516 _Deque_base(const allocator_type& __a, size_t __num_elements) 517 : _M_impl(__a) 518 { _M_initialize_map(__num_elements); } 519 520 _Deque_base(const allocator_type& __a) 521 : _M_impl(__a) 522 { /* Caller must initialize map. */ } 523 524 #if __cplusplus >= 201103L 525 _Deque_base(_Deque_base&& __x, false_type) 526 : _M_impl(__x._M_move_impl()) 527 { } 528 529 _Deque_base(_Deque_base&& __x, true_type) 530 : _M_impl(std::move(__x._M_get_Tp_allocator())) 531 { 532 _M_initialize_map(0); 533 if (__x._M_impl._M_map) 534 this->_M_impl._M_swap_data(__x._M_impl); 535 } 536 537 _Deque_base(_Deque_base&& __x) 538 : _Deque_base(std::move(__x), typename _Alloc_traits::is_always_equal{}) 539 { } 540 541 _Deque_base(_Deque_base&& __x, const allocator_type& __a, size_t __n) 542 : _M_impl(__a) 543 { 544 if (__x.get_allocator() == __a) 545 { 546 if (__x._M_impl._M_map) 547 { 548 _M_initialize_map(0); 549 this->_M_impl._M_swap_data(__x._M_impl); 550 } 551 } 552 else 553 { 554 _M_initialize_map(__n); 555 } 556 } 557 #endif 558 559 ~_Deque_base() _GLIBCXX_NOEXCEPT; 560 561 protected: 562 typedef typename iterator::_Map_pointer _Map_pointer; 563 564 //This struct encapsulates the implementation of the std::deque 565 //standard container and at the same time makes use of the EBO 566 //for empty allocators. 567 struct _Deque_impl 568 : public _Tp_alloc_type 569 { 570 _Map_pointer _M_map; 571 size_t _M_map_size; 572 iterator _M_start; 573 iterator _M_finish; 574 575 _Deque_impl() 576 : _Tp_alloc_type(), _M_map(), _M_map_size(0), 577 _M_start(), _M_finish() 578 { } 579 580 _Deque_impl(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT 581 : _Tp_alloc_type(__a), _M_map(), _M_map_size(0), 582 _M_start(), _M_finish() 583 { } 584 585 #if __cplusplus >= 201103L 586 _Deque_impl(_Deque_impl&&) = default; 587 588 _Deque_impl(_Tp_alloc_type&& __a) noexcept 589 : _Tp_alloc_type(std::move(__a)), _M_map(), _M_map_size(0), 590 _M_start(), _M_finish() 591 { } 592 #endif 593 594 void _M_swap_data(_Deque_impl& __x) _GLIBCXX_NOEXCEPT 595 { 596 using std::swap; 597 swap(this->_M_start, __x._M_start); 598 swap(this->_M_finish, __x._M_finish); 599 swap(this->_M_map, __x._M_map); 600 swap(this->_M_map_size, __x._M_map_size); 601 } 602 }; 603 604 _Tp_alloc_type& 605 _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT 606 { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); } 607 608 const _Tp_alloc_type& 609 _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT 610 { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); } 611 612 _Map_alloc_type 613 _M_get_map_allocator() const _GLIBCXX_NOEXCEPT 614 { return _Map_alloc_type(_M_get_Tp_allocator()); } 615 616 _Ptr 617 _M_allocate_node() 618 { 619 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 620 return _Traits::allocate(_M_impl, __deque_buf_size(sizeof(_Tp))); 621 } 622 623 void 624 _M_deallocate_node(_Ptr __p) _GLIBCXX_NOEXCEPT 625 { 626 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 627 _Traits::deallocate(_M_impl, __p, __deque_buf_size(sizeof(_Tp))); 628 } 629 630 _Map_pointer 631 _M_allocate_map(size_t __n) 632 { 633 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 634 return _Map_alloc_traits::allocate(__map_alloc, __n); 635 } 636 637 void 638 _M_deallocate_map(_Map_pointer __p, size_t __n) _GLIBCXX_NOEXCEPT 639 { 640 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 641 _Map_alloc_traits::deallocate(__map_alloc, __p, __n); 642 } 643 644 protected: 645 void _M_initialize_map(size_t); 646 void _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish); 647 void _M_destroy_nodes(_Map_pointer __nstart, 648 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT; 649 enum { _S_initial_map_size = 8 }; 650 651 _Deque_impl _M_impl; 652 653 #if __cplusplus >= 201103L 654 private: 655 _Deque_impl 656 _M_move_impl() 657 { 658 if (!_M_impl._M_map) 659 return std::move(_M_impl); 660 661 // Create a copy of the current allocator. 662 _Tp_alloc_type __alloc{_M_get_Tp_allocator()}; 663 // Put that copy in a moved-from state. 664 _Tp_alloc_type __sink __attribute((__unused__)) {std::move(__alloc)}; 665 // Create an empty map that allocates using the moved-from allocator. 666 _Deque_base __empty{__alloc}; 667 __empty._M_initialize_map(0); 668 // Now safe to modify current allocator and perform non-throwing swaps. 669 _Deque_impl __ret{std::move(_M_get_Tp_allocator())}; 670 _M_impl._M_swap_data(__ret); 671 _M_impl._M_swap_data(__empty._M_impl); 672 return __ret; 673 } 674 #endif 675 }; 676 677 template<typename _Tp, typename _Alloc> 678 _Deque_base<_Tp, _Alloc>:: 679 ~_Deque_base() _GLIBCXX_NOEXCEPT 680 { 681 if (this->_M_impl._M_map) 682 { 683 _M_destroy_nodes(this->_M_impl._M_start._M_node, 684 this->_M_impl._M_finish._M_node + 1); 685 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 686 } 687 } 688 689 /** 690 * @brief Layout storage. 691 * @param __num_elements The count of T's for which to allocate space 692 * at first. 693 * @return Nothing. 694 * 695 * The initial underlying memory layout is a bit complicated... 696 */ 697 template<typename _Tp, typename _Alloc> 698 void 699 _Deque_base<_Tp, _Alloc>:: 700 _M_initialize_map(size_t __num_elements) 701 { 702 const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp)) 703 + 1); 704 705 this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size, 706 size_t(__num_nodes + 2)); 707 this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size); 708 709 // For "small" maps (needing less than _M_map_size nodes), allocation 710 // starts in the middle elements and grows outwards. So nstart may be 711 // the beginning of _M_map, but for small maps it may be as far in as 712 // _M_map+3. 713 714 _Map_pointer __nstart = (this->_M_impl._M_map 715 + (this->_M_impl._M_map_size - __num_nodes) / 2); 716 _Map_pointer __nfinish = __nstart + __num_nodes; 717 718 __try 719 { _M_create_nodes(__nstart, __nfinish); } 720 __catch(...) 721 { 722 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 723 this->_M_impl._M_map = _Map_pointer(); 724 this->_M_impl._M_map_size = 0; 725 __throw_exception_again; 726 } 727 728 this->_M_impl._M_start._M_set_node(__nstart); 729 this->_M_impl._M_finish._M_set_node(__nfinish - 1); 730 this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first; 731 this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first 732 + __num_elements 733 % __deque_buf_size(sizeof(_Tp))); 734 } 735 736 template<typename _Tp, typename _Alloc> 737 void 738 _Deque_base<_Tp, _Alloc>:: 739 _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish) 740 { 741 _Map_pointer __cur; 742 __try 743 { 744 for (__cur = __nstart; __cur < __nfinish; ++__cur) 745 *__cur = this->_M_allocate_node(); 746 } 747 __catch(...) 748 { 749 _M_destroy_nodes(__nstart, __cur); 750 __throw_exception_again; 751 } 752 } 753 754 template<typename _Tp, typename _Alloc> 755 void 756 _Deque_base<_Tp, _Alloc>:: 757 _M_destroy_nodes(_Map_pointer __nstart, 758 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT 759 { 760 for (_Map_pointer __n = __nstart; __n < __nfinish; ++__n) 761 _M_deallocate_node(*__n); 762 } 763 764 /** 765 * @brief A standard container using fixed-size memory allocation and 766 * constant-time manipulation of elements at either end. 767 * 768 * @ingroup sequences 769 * 770 * @tparam _Tp Type of element. 771 * @tparam _Alloc Allocator type, defaults to allocator<_Tp>. 772 * 773 * Meets the requirements of a <a href="tables.html#65">container</a>, a 774 * <a href="tables.html#66">reversible container</a>, and a 775 * <a href="tables.html#67">sequence</a>, including the 776 * <a href="tables.html#68">optional sequence requirements</a>. 777 * 778 * In previous HP/SGI versions of deque, there was an extra template 779 * parameter so users could control the node size. This extension turned 780 * out to violate the C++ standard (it can be detected using template 781 * template parameters), and it was removed. 782 * 783 * Here's how a deque<Tp> manages memory. Each deque has 4 members: 784 * 785 * - Tp** _M_map 786 * - size_t _M_map_size 787 * - iterator _M_start, _M_finish 788 * 789 * map_size is at least 8. %map is an array of map_size 790 * pointers-to-@a nodes. (The name %map has nothing to do with the 791 * std::map class, and @b nodes should not be confused with 792 * std::list's usage of @a node.) 793 * 794 * A @a node has no specific type name as such, but it is referred 795 * to as @a node in this file. It is a simple array-of-Tp. If Tp 796 * is very large, there will be one Tp element per node (i.e., an 797 * @a array of one). For non-huge Tp's, node size is inversely 798 * related to Tp size: the larger the Tp, the fewer Tp's will fit 799 * in a node. The goal here is to keep the total size of a node 800 * relatively small and constant over different Tp's, to improve 801 * allocator efficiency. 802 * 803 * Not every pointer in the %map array will point to a node. If 804 * the initial number of elements in the deque is small, the 805 * /middle/ %map pointers will be valid, and the ones at the edges 806 * will be unused. This same situation will arise as the %map 807 * grows: available %map pointers, if any, will be on the ends. As 808 * new nodes are created, only a subset of the %map's pointers need 809 * to be copied @a outward. 810 * 811 * Class invariants: 812 * - For any nonsingular iterator i: 813 * - i.node points to a member of the %map array. (Yes, you read that 814 * correctly: i.node does not actually point to a node.) The member of 815 * the %map array is what actually points to the node. 816 * - i.first == *(i.node) (This points to the node (first Tp element).) 817 * - i.last == i.first + node_size 818 * - i.cur is a pointer in the range [i.first, i.last). NOTE: 819 * the implication of this is that i.cur is always a dereferenceable 820 * pointer, even if i is a past-the-end iterator. 821 * - Start and Finish are always nonsingular iterators. NOTE: this 822 * means that an empty deque must have one node, a deque with <N 823 * elements (where N is the node buffer size) must have one node, a 824 * deque with N through (2N-1) elements must have two nodes, etc. 825 * - For every node other than start.node and finish.node, every 826 * element in the node is an initialized object. If start.node == 827 * finish.node, then [start.cur, finish.cur) are initialized 828 * objects, and the elements outside that range are uninitialized 829 * storage. Otherwise, [start.cur, start.last) and [finish.first, 830 * finish.cur) are initialized objects, and [start.first, start.cur) 831 * and [finish.cur, finish.last) are uninitialized storage. 832 * - [%map, %map + map_size) is a valid, non-empty range. 833 * - [start.node, finish.node] is a valid range contained within 834 * [%map, %map + map_size). 835 * - A pointer in the range [%map, %map + map_size) points to an allocated 836 * node if and only if the pointer is in the range 837 * [start.node, finish.node]. 838 * 839 * Here's the magic: nothing in deque is @b aware of the discontiguous 840 * storage! 841 * 842 * The memory setup and layout occurs in the parent, _Base, and the iterator 843 * class is entirely responsible for @a leaping from one node to the next. 844 * All the implementation routines for deque itself work only through the 845 * start and finish iterators. This keeps the routines simple and sane, 846 * and we can use other standard algorithms as well. 847 */ 848 template<typename _Tp, typename _Alloc = std::allocator<_Tp> > 849 class deque : protected _Deque_base<_Tp, _Alloc> 850 { 851 #ifdef _GLIBCXX_CONCEPT_CHECKS 852 // concept requirements 853 typedef typename _Alloc::value_type _Alloc_value_type; 854 # if __cplusplus < 201103L 855 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 856 # endif 857 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept) 858 #endif 859 860 #if __cplusplus >= 201103L 861 static_assert(is_same<typename remove_cv<_Tp>::type, _Tp>::value, 862 "std::deque must have a non-const, non-volatile value_type"); 863 # ifdef __STRICT_ANSI__ 864 static_assert(is_same<typename _Alloc::value_type, _Tp>::value, 865 "std::deque must have the same value_type as its allocator"); 866 # endif 867 #endif 868 869 typedef _Deque_base<_Tp, _Alloc> _Base; 870 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type; 871 typedef typename _Base::_Alloc_traits _Alloc_traits; 872 typedef typename _Base::_Map_pointer _Map_pointer; 873 874 public: 875 typedef _Tp value_type; 876 typedef typename _Alloc_traits::pointer pointer; 877 typedef typename _Alloc_traits::const_pointer const_pointer; 878 typedef typename _Alloc_traits::reference reference; 879 typedef typename _Alloc_traits::const_reference const_reference; 880 typedef typename _Base::iterator iterator; 881 typedef typename _Base::const_iterator const_iterator; 882 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 883 typedef std::reverse_iterator<iterator> reverse_iterator; 884 typedef size_t size_type; 885 typedef ptrdiff_t difference_type; 886 typedef _Alloc allocator_type; 887 888 protected: 889 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 890 { return __deque_buf_size(sizeof(_Tp)); } 891 892 // Functions controlling memory layout, and nothing else. 893 using _Base::_M_initialize_map; 894 using _Base::_M_create_nodes; 895 using _Base::_M_destroy_nodes; 896 using _Base::_M_allocate_node; 897 using _Base::_M_deallocate_node; 898 using _Base::_M_allocate_map; 899 using _Base::_M_deallocate_map; 900 using _Base::_M_get_Tp_allocator; 901 902 /** 903 * A total of four data members accumulated down the hierarchy. 904 * May be accessed via _M_impl.* 905 */ 906 using _Base::_M_impl; 907 908 public: 909 // [23.2.1.1] construct/copy/destroy 910 // (assign() and get_allocator() are also listed in this section) 911 912 /** 913 * @brief Creates a %deque with no elements. 914 */ 915 deque() : _Base() { } 916 917 /** 918 * @brief Creates a %deque with no elements. 919 * @param __a An allocator object. 920 */ 921 explicit 922 deque(const allocator_type& __a) 923 : _Base(__a, 0) { } 924 925 #if __cplusplus >= 201103L 926 /** 927 * @brief Creates a %deque with default constructed elements. 928 * @param __n The number of elements to initially create. 929 * @param __a An allocator. 930 * 931 * This constructor fills the %deque with @a n default 932 * constructed elements. 933 */ 934 explicit 935 deque(size_type __n, const allocator_type& __a = allocator_type()) 936 : _Base(__a, _S_check_init_len(__n, __a)) 937 { _M_default_initialize(); } 938 939 /** 940 * @brief Creates a %deque with copies of an exemplar element. 941 * @param __n The number of elements to initially create. 942 * @param __value An element to copy. 943 * @param __a An allocator. 944 * 945 * This constructor fills the %deque with @a __n copies of @a __value. 946 */ 947 deque(size_type __n, const value_type& __value, 948 const allocator_type& __a = allocator_type()) 949 : _Base(__a, _S_check_init_len(__n, __a)) 950 { _M_fill_initialize(__value); } 951 #else 952 /** 953 * @brief Creates a %deque with copies of an exemplar element. 954 * @param __n The number of elements to initially create. 955 * @param __value An element to copy. 956 * @param __a An allocator. 957 * 958 * This constructor fills the %deque with @a __n copies of @a __value. 959 */ 960 explicit 961 deque(size_type __n, const value_type& __value = value_type(), 962 const allocator_type& __a = allocator_type()) 963 : _Base(__a, _S_check_init_len(__n, __a)) 964 { _M_fill_initialize(__value); } 965 #endif 966 967 /** 968 * @brief %Deque copy constructor. 969 * @param __x A %deque of identical element and allocator types. 970 * 971 * The newly-created %deque uses a copy of the allocator object used 972 * by @a __x (unless the allocator traits dictate a different object). 973 */ 974 deque(const deque& __x) 975 : _Base(_Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()), 976 __x.size()) 977 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 978 this->_M_impl._M_start, 979 _M_get_Tp_allocator()); } 980 981 #if __cplusplus >= 201103L 982 /** 983 * @brief %Deque move constructor. 984 * @param __x A %deque of identical element and allocator types. 985 * 986 * The newly-created %deque contains the exact contents of @a __x. 987 * The contents of @a __x are a valid, but unspecified %deque. 988 */ 989 deque(deque&& __x) 990 : _Base(std::move(__x)) { } 991 992 /// Copy constructor with alternative allocator 993 deque(const deque& __x, const allocator_type& __a) 994 : _Base(__a, __x.size()) 995 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 996 this->_M_impl._M_start, 997 _M_get_Tp_allocator()); } 998 999 /// Move constructor with alternative allocator 1000 deque(deque&& __x, const allocator_type& __a) 1001 : _Base(std::move(__x), __a, __x.size()) 1002 { 1003 if (__x.get_allocator() != __a) 1004 { 1005 std::__uninitialized_move_a(__x.begin(), __x.end(), 1006 this->_M_impl._M_start, 1007 _M_get_Tp_allocator()); 1008 __x.clear(); 1009 } 1010 } 1011 1012 /** 1013 * @brief Builds a %deque from an initializer list. 1014 * @param __l An initializer_list. 1015 * @param __a An allocator object. 1016 * 1017 * Create a %deque consisting of copies of the elements in the 1018 * initializer_list @a __l. 1019 * 1020 * This will call the element type's copy constructor N times 1021 * (where N is __l.size()) and do no memory reallocation. 1022 */ 1023 deque(initializer_list<value_type> __l, 1024 const allocator_type& __a = allocator_type()) 1025 : _Base(__a) 1026 { 1027 _M_range_initialize(__l.begin(), __l.end(), 1028 random_access_iterator_tag()); 1029 } 1030 #endif 1031 1032 /** 1033 * @brief Builds a %deque from a range. 1034 * @param __first An input iterator. 1035 * @param __last An input iterator. 1036 * @param __a An allocator object. 1037 * 1038 * Create a %deque consisting of copies of the elements from [__first, 1039 * __last). 1040 * 1041 * If the iterators are forward, bidirectional, or random-access, then 1042 * this will call the elements' copy constructor N times (where N is 1043 * distance(__first,__last)) and do no memory reallocation. But if only 1044 * input iterators are used, then this will do at most 2N calls to the 1045 * copy constructor, and logN memory reallocations. 1046 */ 1047 #if __cplusplus >= 201103L 1048 template<typename _InputIterator, 1049 typename = std::_RequireInputIter<_InputIterator>> 1050 deque(_InputIterator __first, _InputIterator __last, 1051 const allocator_type& __a = allocator_type()) 1052 : _Base(__a) 1053 { _M_initialize_dispatch(__first, __last, __false_type()); } 1054 #else 1055 template<typename _InputIterator> 1056 deque(_InputIterator __first, _InputIterator __last, 1057 const allocator_type& __a = allocator_type()) 1058 : _Base(__a) 1059 { 1060 // Check whether it's an integral type. If so, it's not an iterator. 1061 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1062 _M_initialize_dispatch(__first, __last, _Integral()); 1063 } 1064 #endif 1065 1066 /** 1067 * The dtor only erases the elements, and note that if the elements 1068 * themselves are pointers, the pointed-to memory is not touched in any 1069 * way. Managing the pointer is the user's responsibility. 1070 */ 1071 ~deque() 1072 { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); } 1073 1074 /** 1075 * @brief %Deque assignment operator. 1076 * @param __x A %deque of identical element and allocator types. 1077 * 1078 * All the elements of @a x are copied. 1079 * 1080 * The newly-created %deque uses a copy of the allocator object used 1081 * by @a __x (unless the allocator traits dictate a different object). 1082 */ 1083 deque& 1084 operator=(const deque& __x); 1085 1086 #if __cplusplus >= 201103L 1087 /** 1088 * @brief %Deque move assignment operator. 1089 * @param __x A %deque of identical element and allocator types. 1090 * 1091 * The contents of @a __x are moved into this deque (without copying, 1092 * if the allocators permit it). 1093 * @a __x is a valid, but unspecified %deque. 1094 */ 1095 deque& 1096 operator=(deque&& __x) noexcept(_Alloc_traits::_S_always_equal()) 1097 { 1098 using __always_equal = typename _Alloc_traits::is_always_equal; 1099 _M_move_assign1(std::move(__x), __always_equal{}); 1100 return *this; 1101 } 1102 1103 /** 1104 * @brief Assigns an initializer list to a %deque. 1105 * @param __l An initializer_list. 1106 * 1107 * This function fills a %deque with copies of the elements in the 1108 * initializer_list @a __l. 1109 * 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. 1113 */ 1114 deque& 1115 operator=(initializer_list<value_type> __l) 1116 { 1117 _M_assign_aux(__l.begin(), __l.end(), 1118 random_access_iterator_tag()); 1119 return *this; 1120 } 1121 #endif 1122 1123 /** 1124 * @brief Assigns a given value to a %deque. 1125 * @param __n Number of elements to be assigned. 1126 * @param __val Value to be assigned. 1127 * 1128 * This function fills a %deque with @a n copies of the given 1129 * value. Note that the assignment completely changes the 1130 * %deque and that the resulting %deque's size is the same as 1131 * the number of elements assigned. 1132 */ 1133 void 1134 assign(size_type __n, const value_type& __val) 1135 { _M_fill_assign(__n, __val); } 1136 1137 /** 1138 * @brief Assigns a range to a %deque. 1139 * @param __first An input iterator. 1140 * @param __last An input iterator. 1141 * 1142 * This function fills a %deque with copies of the elements in the 1143 * range [__first,__last). 1144 * 1145 * Note that the assignment completely changes the %deque and that the 1146 * resulting %deque's size is the same as the number of elements 1147 * assigned. 1148 */ 1149 #if __cplusplus >= 201103L 1150 template<typename _InputIterator, 1151 typename = std::_RequireInputIter<_InputIterator>> 1152 void 1153 assign(_InputIterator __first, _InputIterator __last) 1154 { _M_assign_dispatch(__first, __last, __false_type()); } 1155 #else 1156 template<typename _InputIterator> 1157 void 1158 assign(_InputIterator __first, _InputIterator __last) 1159 { 1160 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1161 _M_assign_dispatch(__first, __last, _Integral()); 1162 } 1163 #endif 1164 1165 #if __cplusplus >= 201103L 1166 /** 1167 * @brief Assigns an initializer list to a %deque. 1168 * @param __l An initializer_list. 1169 * 1170 * This function fills a %deque with copies of the elements in the 1171 * initializer_list @a __l. 1172 * 1173 * Note that the assignment completely changes the %deque and that the 1174 * resulting %deque's size is the same as the number of elements 1175 * assigned. 1176 */ 1177 void 1178 assign(initializer_list<value_type> __l) 1179 { _M_assign_aux(__l.begin(), __l.end(), random_access_iterator_tag()); } 1180 #endif 1181 1182 /// Get a copy of the memory allocation object. 1183 allocator_type 1184 get_allocator() const _GLIBCXX_NOEXCEPT 1185 { return _Base::get_allocator(); } 1186 1187 // iterators 1188 /** 1189 * Returns a read/write iterator that points to the first element in the 1190 * %deque. Iteration is done in ordinary element order. 1191 */ 1192 iterator 1193 begin() _GLIBCXX_NOEXCEPT 1194 { return this->_M_impl._M_start; } 1195 1196 /** 1197 * Returns a read-only (constant) iterator that points to the first 1198 * element in the %deque. Iteration is done in ordinary element order. 1199 */ 1200 const_iterator 1201 begin() const _GLIBCXX_NOEXCEPT 1202 { return this->_M_impl._M_start; } 1203 1204 /** 1205 * Returns a read/write iterator that points one past the last 1206 * element in the %deque. Iteration is done in ordinary 1207 * element order. 1208 */ 1209 iterator 1210 end() _GLIBCXX_NOEXCEPT 1211 { return this->_M_impl._M_finish; } 1212 1213 /** 1214 * Returns a read-only (constant) iterator that points one past 1215 * the last element in the %deque. Iteration is done in 1216 * ordinary element order. 1217 */ 1218 const_iterator 1219 end() const _GLIBCXX_NOEXCEPT 1220 { return this->_M_impl._M_finish; } 1221 1222 /** 1223 * Returns a read/write reverse iterator that points to the 1224 * last element in the %deque. Iteration is done in reverse 1225 * element order. 1226 */ 1227 reverse_iterator 1228 rbegin() _GLIBCXX_NOEXCEPT 1229 { return reverse_iterator(this->_M_impl._M_finish); } 1230 1231 /** 1232 * Returns a read-only (constant) reverse iterator that points 1233 * to the last element in the %deque. Iteration is done in 1234 * reverse element order. 1235 */ 1236 const_reverse_iterator 1237 rbegin() const _GLIBCXX_NOEXCEPT 1238 { return const_reverse_iterator(this->_M_impl._M_finish); } 1239 1240 /** 1241 * Returns a read/write reverse iterator that points to one 1242 * before the first element in the %deque. Iteration is done 1243 * in reverse element order. 1244 */ 1245 reverse_iterator 1246 rend() _GLIBCXX_NOEXCEPT 1247 { return reverse_iterator(this->_M_impl._M_start); } 1248 1249 /** 1250 * Returns a read-only (constant) reverse iterator that points 1251 * to one before the first element in the %deque. Iteration is 1252 * done in reverse element order. 1253 */ 1254 const_reverse_iterator 1255 rend() const _GLIBCXX_NOEXCEPT 1256 { return const_reverse_iterator(this->_M_impl._M_start); } 1257 1258 #if __cplusplus >= 201103L 1259 /** 1260 * Returns a read-only (constant) iterator that points to the first 1261 * element in the %deque. Iteration is done in ordinary element order. 1262 */ 1263 const_iterator 1264 cbegin() const noexcept 1265 { return this->_M_impl._M_start; } 1266 1267 /** 1268 * Returns a read-only (constant) iterator that points one past 1269 * the last element in the %deque. Iteration is done in 1270 * ordinary element order. 1271 */ 1272 const_iterator 1273 cend() const noexcept 1274 { return this->_M_impl._M_finish; } 1275 1276 /** 1277 * Returns a read-only (constant) reverse iterator that points 1278 * to the last element in the %deque. Iteration is done in 1279 * reverse element order. 1280 */ 1281 const_reverse_iterator 1282 crbegin() const noexcept 1283 { return const_reverse_iterator(this->_M_impl._M_finish); } 1284 1285 /** 1286 * Returns a read-only (constant) reverse iterator that points 1287 * to one before the first element in the %deque. Iteration is 1288 * done in reverse element order. 1289 */ 1290 const_reverse_iterator 1291 crend() const noexcept 1292 { return const_reverse_iterator(this->_M_impl._M_start); } 1293 #endif 1294 1295 // [23.2.1.2] capacity 1296 /** Returns the number of elements in the %deque. */ 1297 size_type 1298 size() const _GLIBCXX_NOEXCEPT 1299 { return this->_M_impl._M_finish - this->_M_impl._M_start; } 1300 1301 /** Returns the size() of the largest possible %deque. */ 1302 size_type 1303 max_size() const _GLIBCXX_NOEXCEPT 1304 { return _S_max_size(_M_get_Tp_allocator()); } 1305 1306 #if __cplusplus >= 201103L 1307 /** 1308 * @brief Resizes the %deque to the specified number of elements. 1309 * @param __new_size Number of elements the %deque should contain. 1310 * 1311 * This function will %resize the %deque to the specified 1312 * number of elements. If the number is smaller than the 1313 * %deque's current size the %deque is truncated, otherwise 1314 * default constructed elements are appended. 1315 */ 1316 void 1317 resize(size_type __new_size) 1318 { 1319 const size_type __len = size(); 1320 if (__new_size > __len) 1321 _M_default_append(__new_size - __len); 1322 else if (__new_size < __len) 1323 _M_erase_at_end(this->_M_impl._M_start 1324 + difference_type(__new_size)); 1325 } 1326 1327 /** 1328 * @brief Resizes the %deque to the specified number of elements. 1329 * @param __new_size Number of elements the %deque should contain. 1330 * @param __x Data with which new elements should be populated. 1331 * 1332 * This function will %resize the %deque to the specified 1333 * number of elements. If the number is smaller than the 1334 * %deque's current size the %deque is truncated, otherwise the 1335 * %deque is extended and new elements are populated with given 1336 * data. 1337 */ 1338 void 1339 resize(size_type __new_size, const value_type& __x) 1340 { 1341 const size_type __len = size(); 1342 if (__new_size > __len) 1343 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1344 else if (__new_size < __len) 1345 _M_erase_at_end(this->_M_impl._M_start 1346 + difference_type(__new_size)); 1347 } 1348 #else 1349 /** 1350 * @brief Resizes the %deque to the specified number of elements. 1351 * @param __new_size Number of elements the %deque should contain. 1352 * @param __x Data with which new elements should be populated. 1353 * 1354 * This function will %resize the %deque to the specified 1355 * number of elements. If the number is smaller than the 1356 * %deque's current size the %deque is truncated, otherwise the 1357 * %deque is extended and new elements are populated with given 1358 * data. 1359 */ 1360 void 1361 resize(size_type __new_size, value_type __x = value_type()) 1362 { 1363 const size_type __len = size(); 1364 if (__new_size > __len) 1365 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1366 else if (__new_size < __len) 1367 _M_erase_at_end(this->_M_impl._M_start 1368 + difference_type(__new_size)); 1369 } 1370 #endif 1371 1372 #if __cplusplus >= 201103L 1373 /** A non-binding request to reduce memory use. */ 1374 void 1375 shrink_to_fit() noexcept 1376 { _M_shrink_to_fit(); } 1377 #endif 1378 1379 /** 1380 * Returns true if the %deque is empty. (Thus begin() would 1381 * equal end().) 1382 */ 1383 _GLIBCXX_NODISCARD bool 1384 empty() const _GLIBCXX_NOEXCEPT 1385 { return this->_M_impl._M_finish == this->_M_impl._M_start; } 1386 1387 // element access 1388 /** 1389 * @brief Subscript access to the data contained in the %deque. 1390 * @param __n The index of the element for which data should be 1391 * accessed. 1392 * @return Read/write reference to data. 1393 * 1394 * This operator allows for easy, array-style, data access. 1395 * Note that data access with this operator is unchecked and 1396 * out_of_range lookups are not defined. (For checked lookups 1397 * see at().) 1398 */ 1399 reference 1400 operator[](size_type __n) _GLIBCXX_NOEXCEPT 1401 { 1402 __glibcxx_requires_subscript(__n); 1403 return this->_M_impl._M_start[difference_type(__n)]; 1404 } 1405 1406 /** 1407 * @brief Subscript access to the data contained in the %deque. 1408 * @param __n The index of the element for which data should be 1409 * accessed. 1410 * @return Read-only (constant) reference to data. 1411 * 1412 * This operator allows for easy, array-style, data access. 1413 * Note that data access with this operator is unchecked and 1414 * out_of_range lookups are not defined. (For checked lookups 1415 * see at().) 1416 */ 1417 const_reference 1418 operator[](size_type __n) const _GLIBCXX_NOEXCEPT 1419 { 1420 __glibcxx_requires_subscript(__n); 1421 return this->_M_impl._M_start[difference_type(__n)]; 1422 } 1423 1424 protected: 1425 /// Safety check used only from at(). 1426 void 1427 _M_range_check(size_type __n) const 1428 { 1429 if (__n >= this->size()) 1430 __throw_out_of_range_fmt(__N("deque::_M_range_check: __n " 1431 "(which is %zu)>= this->size() " 1432 "(which is %zu)"), 1433 __n, this->size()); 1434 } 1435 1436 public: 1437 /** 1438 * @brief Provides access to the data contained in the %deque. 1439 * @param __n The index of the element for which data should be 1440 * accessed. 1441 * @return Read/write reference to data. 1442 * @throw std::out_of_range If @a __n is an invalid index. 1443 * 1444 * This function provides for safer data access. The parameter 1445 * is first checked that it is in the range of the deque. The 1446 * function throws out_of_range if the check fails. 1447 */ 1448 reference 1449 at(size_type __n) 1450 { 1451 _M_range_check(__n); 1452 return (*this)[__n]; 1453 } 1454 1455 /** 1456 * @brief Provides access to the data contained in the %deque. 1457 * @param __n The index of the element for which data should be 1458 * accessed. 1459 * @return Read-only (constant) reference to data. 1460 * @throw std::out_of_range If @a __n is an invalid index. 1461 * 1462 * This function provides for safer data access. The parameter is first 1463 * checked that it is in the range of the deque. The function throws 1464 * out_of_range if the check fails. 1465 */ 1466 const_reference 1467 at(size_type __n) const 1468 { 1469 _M_range_check(__n); 1470 return (*this)[__n]; 1471 } 1472 1473 /** 1474 * Returns a read/write reference to the data at the first 1475 * element of the %deque. 1476 */ 1477 reference 1478 front() _GLIBCXX_NOEXCEPT 1479 { 1480 __glibcxx_requires_nonempty(); 1481 return *begin(); 1482 } 1483 1484 /** 1485 * Returns a read-only (constant) reference to the data at the first 1486 * element of the %deque. 1487 */ 1488 const_reference 1489 front() const _GLIBCXX_NOEXCEPT 1490 { 1491 __glibcxx_requires_nonempty(); 1492 return *begin(); 1493 } 1494 1495 /** 1496 * Returns a read/write reference to the data at the last element of the 1497 * %deque. 1498 */ 1499 reference 1500 back() _GLIBCXX_NOEXCEPT 1501 { 1502 __glibcxx_requires_nonempty(); 1503 iterator __tmp = end(); 1504 --__tmp; 1505 return *__tmp; 1506 } 1507 1508 /** 1509 * Returns a read-only (constant) reference to the data at the last 1510 * element of the %deque. 1511 */ 1512 const_reference 1513 back() const _GLIBCXX_NOEXCEPT 1514 { 1515 __glibcxx_requires_nonempty(); 1516 const_iterator __tmp = end(); 1517 --__tmp; 1518 return *__tmp; 1519 } 1520 1521 // [23.2.1.2] modifiers 1522 /** 1523 * @brief Add data to the front of the %deque. 1524 * @param __x Data to be added. 1525 * 1526 * This is a typical stack operation. The function creates an 1527 * element at the front of the %deque and assigns the given 1528 * data to it. Due to the nature of a %deque this operation 1529 * can be done in constant time. 1530 */ 1531 void 1532 push_front(const value_type& __x) 1533 { 1534 if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first) 1535 { 1536 _Alloc_traits::construct(this->_M_impl, 1537 this->_M_impl._M_start._M_cur - 1, 1538 __x); 1539 --this->_M_impl._M_start._M_cur; 1540 } 1541 else 1542 _M_push_front_aux(__x); 1543 } 1544 1545 #if __cplusplus >= 201103L 1546 void 1547 push_front(value_type&& __x) 1548 { emplace_front(std::move(__x)); } 1549 1550 template<typename... _Args> 1551 #if __cplusplus > 201402L 1552 reference 1553 #else 1554 void 1555 #endif 1556 emplace_front(_Args&&... __args); 1557 #endif 1558 1559 /** 1560 * @brief Add data to the end of the %deque. 1561 * @param __x Data to be added. 1562 * 1563 * This is a typical stack operation. The function creates an 1564 * element at the end of the %deque and assigns the given data 1565 * to it. Due to the nature of a %deque this operation can be 1566 * done in constant time. 1567 */ 1568 void 1569 push_back(const value_type& __x) 1570 { 1571 if (this->_M_impl._M_finish._M_cur 1572 != this->_M_impl._M_finish._M_last - 1) 1573 { 1574 _Alloc_traits::construct(this->_M_impl, 1575 this->_M_impl._M_finish._M_cur, __x); 1576 ++this->_M_impl._M_finish._M_cur; 1577 } 1578 else 1579 _M_push_back_aux(__x); 1580 } 1581 1582 #if __cplusplus >= 201103L 1583 void 1584 push_back(value_type&& __x) 1585 { emplace_back(std::move(__x)); } 1586 1587 template<typename... _Args> 1588 #if __cplusplus > 201402L 1589 reference 1590 #else 1591 void 1592 #endif 1593 emplace_back(_Args&&... __args); 1594 #endif 1595 1596 /** 1597 * @brief Removes first element. 1598 * 1599 * This is a typical stack operation. It shrinks the %deque by one. 1600 * 1601 * Note that no data is returned, and if the first element's data is 1602 * needed, it should be retrieved before pop_front() is called. 1603 */ 1604 void 1605 pop_front() _GLIBCXX_NOEXCEPT 1606 { 1607 __glibcxx_requires_nonempty(); 1608 if (this->_M_impl._M_start._M_cur 1609 != this->_M_impl._M_start._M_last - 1) 1610 { 1611 _Alloc_traits::destroy(this->_M_impl, 1612 this->_M_impl._M_start._M_cur); 1613 ++this->_M_impl._M_start._M_cur; 1614 } 1615 else 1616 _M_pop_front_aux(); 1617 } 1618 1619 /** 1620 * @brief Removes last element. 1621 * 1622 * This is a typical stack operation. It shrinks the %deque by one. 1623 * 1624 * Note that no data is returned, and if the last element's data is 1625 * needed, it should be retrieved before pop_back() is called. 1626 */ 1627 void 1628 pop_back() _GLIBCXX_NOEXCEPT 1629 { 1630 __glibcxx_requires_nonempty(); 1631 if (this->_M_impl._M_finish._M_cur 1632 != this->_M_impl._M_finish._M_first) 1633 { 1634 --this->_M_impl._M_finish._M_cur; 1635 _Alloc_traits::destroy(this->_M_impl, 1636 this->_M_impl._M_finish._M_cur); 1637 } 1638 else 1639 _M_pop_back_aux(); 1640 } 1641 1642 #if __cplusplus >= 201103L 1643 /** 1644 * @brief Inserts an object in %deque before specified iterator. 1645 * @param __position A const_iterator into the %deque. 1646 * @param __args Arguments. 1647 * @return An iterator that points to the inserted data. 1648 * 1649 * This function will insert an object of type T constructed 1650 * with T(std::forward<Args>(args)...) before the specified location. 1651 */ 1652 template<typename... _Args> 1653 iterator 1654 emplace(const_iterator __position, _Args&&... __args); 1655 1656 /** 1657 * @brief Inserts given value into %deque before specified iterator. 1658 * @param __position A const_iterator into the %deque. 1659 * @param __x Data to be inserted. 1660 * @return An iterator that points to the inserted data. 1661 * 1662 * This function will insert a copy of the given value before the 1663 * specified location. 1664 */ 1665 iterator 1666 insert(const_iterator __position, const value_type& __x); 1667 #else 1668 /** 1669 * @brief Inserts given value into %deque before specified iterator. 1670 * @param __position An iterator into the %deque. 1671 * @param __x Data to be inserted. 1672 * @return An iterator that points to the inserted data. 1673 * 1674 * This function will insert a copy of the given value before the 1675 * specified location. 1676 */ 1677 iterator 1678 insert(iterator __position, const value_type& __x); 1679 #endif 1680 1681 #if __cplusplus >= 201103L 1682 /** 1683 * @brief Inserts given rvalue into %deque before specified iterator. 1684 * @param __position A const_iterator into the %deque. 1685 * @param __x Data to be inserted. 1686 * @return An iterator that points to the inserted data. 1687 * 1688 * This function will insert a copy of the given rvalue before the 1689 * specified location. 1690 */ 1691 iterator 1692 insert(const_iterator __position, value_type&& __x) 1693 { return emplace(__position, std::move(__x)); } 1694 1695 /** 1696 * @brief Inserts an initializer list into the %deque. 1697 * @param __p An iterator into the %deque. 1698 * @param __l An initializer_list. 1699 * 1700 * This function will insert copies of the data in the 1701 * initializer_list @a __l into the %deque before the location 1702 * specified by @a __p. This is known as <em>list insert</em>. 1703 */ 1704 iterator 1705 insert(const_iterator __p, initializer_list<value_type> __l) 1706 { 1707 auto __offset = __p - cbegin(); 1708 _M_range_insert_aux(__p._M_const_cast(), __l.begin(), __l.end(), 1709 std::random_access_iterator_tag()); 1710 return begin() + __offset; 1711 } 1712 #endif 1713 1714 #if __cplusplus >= 201103L 1715 /** 1716 * @brief Inserts a number of copies of given data into the %deque. 1717 * @param __position A const_iterator into the %deque. 1718 * @param __n Number of elements to be inserted. 1719 * @param __x Data to be inserted. 1720 * @return An iterator that points to the inserted data. 1721 * 1722 * This function will insert a specified number of copies of the given 1723 * data before the location specified by @a __position. 1724 */ 1725 iterator 1726 insert(const_iterator __position, size_type __n, const value_type& __x) 1727 { 1728 difference_type __offset = __position - cbegin(); 1729 _M_fill_insert(__position._M_const_cast(), __n, __x); 1730 return begin() + __offset; 1731 } 1732 #else 1733 /** 1734 * @brief Inserts a number of copies of given data into the %deque. 1735 * @param __position An iterator into the %deque. 1736 * @param __n Number of elements to be inserted. 1737 * @param __x Data to be inserted. 1738 * 1739 * This function will insert a specified number of copies of the given 1740 * data before the location specified by @a __position. 1741 */ 1742 void 1743 insert(iterator __position, size_type __n, const value_type& __x) 1744 { _M_fill_insert(__position, __n, __x); } 1745 #endif 1746 1747 #if __cplusplus >= 201103L 1748 /** 1749 * @brief Inserts a range into the %deque. 1750 * @param __position A const_iterator into the %deque. 1751 * @param __first An input iterator. 1752 * @param __last An input iterator. 1753 * @return An iterator that points to the inserted data. 1754 * 1755 * This function will insert copies of the data in the range 1756 * [__first,__last) into the %deque before the location specified 1757 * by @a __position. This is known as <em>range insert</em>. 1758 */ 1759 template<typename _InputIterator, 1760 typename = std::_RequireInputIter<_InputIterator>> 1761 iterator 1762 insert(const_iterator __position, _InputIterator __first, 1763 _InputIterator __last) 1764 { 1765 difference_type __offset = __position - cbegin(); 1766 _M_insert_dispatch(__position._M_const_cast(), 1767 __first, __last, __false_type()); 1768 return begin() + __offset; 1769 } 1770 #else 1771 /** 1772 * @brief Inserts a range into the %deque. 1773 * @param __position An iterator into the %deque. 1774 * @param __first An input iterator. 1775 * @param __last An input iterator. 1776 * 1777 * This function will insert copies of the data in the range 1778 * [__first,__last) into the %deque before the location specified 1779 * by @a __position. This is known as <em>range insert</em>. 1780 */ 1781 template<typename _InputIterator> 1782 void 1783 insert(iterator __position, _InputIterator __first, 1784 _InputIterator __last) 1785 { 1786 // Check whether it's an integral type. If so, it's not an iterator. 1787 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1788 _M_insert_dispatch(__position, __first, __last, _Integral()); 1789 } 1790 #endif 1791 1792 /** 1793 * @brief Remove element at given position. 1794 * @param __position Iterator pointing to element to be erased. 1795 * @return An iterator pointing to the next element (or end()). 1796 * 1797 * This function will erase the element at the given position and thus 1798 * shorten the %deque by one. 1799 * 1800 * The user is cautioned that 1801 * this function only erases the element, and that if the element is 1802 * itself a pointer, the pointed-to memory is not touched in any way. 1803 * Managing the pointer is the user's responsibility. 1804 */ 1805 iterator 1806 #if __cplusplus >= 201103L 1807 erase(const_iterator __position) 1808 #else 1809 erase(iterator __position) 1810 #endif 1811 { return _M_erase(__position._M_const_cast()); } 1812 1813 /** 1814 * @brief Remove a range of elements. 1815 * @param __first Iterator pointing to the first element to be erased. 1816 * @param __last Iterator pointing to one past the last element to be 1817 * erased. 1818 * @return An iterator pointing to the element pointed to by @a last 1819 * prior to erasing (or end()). 1820 * 1821 * This function will erase the elements in the range 1822 * [__first,__last) and shorten the %deque accordingly. 1823 * 1824 * The user is cautioned that 1825 * this function only erases the elements, and that if the elements 1826 * themselves are pointers, the pointed-to memory is not touched in any 1827 * way. Managing the pointer is the user's responsibility. 1828 */ 1829 iterator 1830 #if __cplusplus >= 201103L 1831 erase(const_iterator __first, const_iterator __last) 1832 #else 1833 erase(iterator __first, iterator __last) 1834 #endif 1835 { return _M_erase(__first._M_const_cast(), __last._M_const_cast()); } 1836 1837 /** 1838 * @brief Swaps data with another %deque. 1839 * @param __x A %deque of the same element and allocator types. 1840 * 1841 * This exchanges the elements between two deques in constant time. 1842 * (Four pointers, so it should be quite fast.) 1843 * Note that the global std::swap() function is specialized such that 1844 * std::swap(d1,d2) will feed to this function. 1845 * 1846 * Whether the allocators are swapped depends on the allocator traits. 1847 */ 1848 void 1849 swap(deque& __x) _GLIBCXX_NOEXCEPT 1850 { 1851 #if __cplusplus >= 201103L 1852 __glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value 1853 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator()); 1854 #endif 1855 _M_impl._M_swap_data(__x._M_impl); 1856 _Alloc_traits::_S_on_swap(_M_get_Tp_allocator(), 1857 __x._M_get_Tp_allocator()); 1858 } 1859 1860 /** 1861 * Erases all the elements. Note that this function only erases the 1862 * elements, and that if the elements themselves are pointers, the 1863 * pointed-to memory is not touched in any way. Managing the pointer is 1864 * the user's responsibility. 1865 */ 1866 void 1867 clear() _GLIBCXX_NOEXCEPT 1868 { _M_erase_at_end(begin()); } 1869 1870 protected: 1871 // Internal constructor functions follow. 1872 1873 // called by the range constructor to implement [23.1.1]/9 1874 1875 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1876 // 438. Ambiguity in the "do the right thing" clause 1877 template<typename _Integer> 1878 void 1879 _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type) 1880 { 1881 _M_initialize_map(_S_check_init_len(static_cast<size_type>(__n), 1882 _M_get_Tp_allocator())); 1883 _M_fill_initialize(__x); 1884 } 1885 1886 static size_t 1887 _S_check_init_len(size_t __n, const allocator_type& __a) 1888 { 1889 if (__n > _S_max_size(__a)) 1890 __throw_length_error( 1891 __N("cannot create std::deque larger than max_size()")); 1892 return __n; 1893 } 1894 1895 static size_type 1896 _S_max_size(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT 1897 { 1898 const size_t __diffmax = __gnu_cxx::__numeric_traits<ptrdiff_t>::__max; 1899 const size_t __allocmax = _Alloc_traits::max_size(__a); 1900 return (std::min)(__diffmax, __allocmax); 1901 } 1902 1903 // called by the range constructor to implement [23.1.1]/9 1904 template<typename _InputIterator> 1905 void 1906 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last, 1907 __false_type) 1908 { 1909 _M_range_initialize(__first, __last, 1910 std::__iterator_category(__first)); 1911 } 1912 1913 // called by the second initialize_dispatch above 1914 //@{ 1915 /** 1916 * @brief Fills the deque with whatever is in [first,last). 1917 * @param __first An input iterator. 1918 * @param __last An input iterator. 1919 * @return Nothing. 1920 * 1921 * If the iterators are actually forward iterators (or better), then the 1922 * memory layout can be done all at once. Else we move forward using 1923 * push_back on each value from the iterator. 1924 */ 1925 template<typename _InputIterator> 1926 void 1927 _M_range_initialize(_InputIterator __first, _InputIterator __last, 1928 std::input_iterator_tag); 1929 1930 // called by the second initialize_dispatch above 1931 template<typename _ForwardIterator> 1932 void 1933 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last, 1934 std::forward_iterator_tag); 1935 //@} 1936 1937 /** 1938 * @brief Fills the %deque with copies of value. 1939 * @param __value Initial value. 1940 * @return Nothing. 1941 * @pre _M_start and _M_finish have already been initialized, 1942 * but none of the %deque's elements have yet been constructed. 1943 * 1944 * This function is called only when the user provides an explicit size 1945 * (with or without an explicit exemplar value). 1946 */ 1947 void 1948 _M_fill_initialize(const value_type& __value); 1949 1950 #if __cplusplus >= 201103L 1951 // called by deque(n). 1952 void 1953 _M_default_initialize(); 1954 #endif 1955 1956 // Internal assign functions follow. The *_aux functions do the actual 1957 // assignment work for the range versions. 1958 1959 // called by the range assign to implement [23.1.1]/9 1960 1961 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1962 // 438. Ambiguity in the "do the right thing" clause 1963 template<typename _Integer> 1964 void 1965 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) 1966 { _M_fill_assign(__n, __val); } 1967 1968 // called by the range assign to implement [23.1.1]/9 1969 template<typename _InputIterator> 1970 void 1971 _M_assign_dispatch(_InputIterator __first, _InputIterator __last, 1972 __false_type) 1973 { _M_assign_aux(__first, __last, std::__iterator_category(__first)); } 1974 1975 // called by the second assign_dispatch above 1976 template<typename _InputIterator> 1977 void 1978 _M_assign_aux(_InputIterator __first, _InputIterator __last, 1979 std::input_iterator_tag); 1980 1981 // called by the second assign_dispatch above 1982 template<typename _ForwardIterator> 1983 void 1984 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last, 1985 std::forward_iterator_tag) 1986 { 1987 const size_type __len = std::distance(__first, __last); 1988 if (__len > size()) 1989 { 1990 _ForwardIterator __mid = __first; 1991 std::advance(__mid, size()); 1992 std::copy(__first, __mid, begin()); 1993 _M_range_insert_aux(end(), __mid, __last, 1994 std::__iterator_category(__first)); 1995 } 1996 else 1997 _M_erase_at_end(std::copy(__first, __last, begin())); 1998 } 1999 2000 // Called by assign(n,t), and the range assign when it turns out 2001 // to be the same thing. 2002 void 2003 _M_fill_assign(size_type __n, const value_type& __val) 2004 { 2005 if (__n > size()) 2006 { 2007 std::fill(begin(), end(), __val); 2008 _M_fill_insert(end(), __n - size(), __val); 2009 } 2010 else 2011 { 2012 _M_erase_at_end(begin() + difference_type(__n)); 2013 std::fill(begin(), end(), __val); 2014 } 2015 } 2016 2017 //@{ 2018 /// Helper functions for push_* and pop_*. 2019 #if __cplusplus < 201103L 2020 void _M_push_back_aux(const value_type&); 2021 2022 void _M_push_front_aux(const value_type&); 2023 #else 2024 template<typename... _Args> 2025 void _M_push_back_aux(_Args&&... __args); 2026 2027 template<typename... _Args> 2028 void _M_push_front_aux(_Args&&... __args); 2029 #endif 2030 2031 void _M_pop_back_aux(); 2032 2033 void _M_pop_front_aux(); 2034 //@} 2035 2036 // Internal insert functions follow. The *_aux functions do the actual 2037 // insertion work when all shortcuts fail. 2038 2039 // called by the range insert to implement [23.1.1]/9 2040 2041 // _GLIBCXX_RESOLVE_LIB_DEFECTS 2042 // 438. Ambiguity in the "do the right thing" clause 2043 template<typename _Integer> 2044 void 2045 _M_insert_dispatch(iterator __pos, 2046 _Integer __n, _Integer __x, __true_type) 2047 { _M_fill_insert(__pos, __n, __x); } 2048 2049 // called by the range insert to implement [23.1.1]/9 2050 template<typename _InputIterator> 2051 void 2052 _M_insert_dispatch(iterator __pos, 2053 _InputIterator __first, _InputIterator __last, 2054 __false_type) 2055 { 2056 _M_range_insert_aux(__pos, __first, __last, 2057 std::__iterator_category(__first)); 2058 } 2059 2060 // called by the second insert_dispatch above 2061 template<typename _InputIterator> 2062 void 2063 _M_range_insert_aux(iterator __pos, _InputIterator __first, 2064 _InputIterator __last, std::input_iterator_tag); 2065 2066 // called by the second insert_dispatch above 2067 template<typename _ForwardIterator> 2068 void 2069 _M_range_insert_aux(iterator __pos, _ForwardIterator __first, 2070 _ForwardIterator __last, std::forward_iterator_tag); 2071 2072 // Called by insert(p,n,x), and the range insert when it turns out to be 2073 // the same thing. Can use fill functions in optimal situations, 2074 // otherwise passes off to insert_aux(p,n,x). 2075 void 2076 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x); 2077 2078 // called by insert(p,x) 2079 #if __cplusplus < 201103L 2080 iterator 2081 _M_insert_aux(iterator __pos, const value_type& __x); 2082 #else 2083 template<typename... _Args> 2084 iterator 2085 _M_insert_aux(iterator __pos, _Args&&... __args); 2086 #endif 2087 2088 // called by insert(p,n,x) via fill_insert 2089 void 2090 _M_insert_aux(iterator __pos, size_type __n, const value_type& __x); 2091 2092 // called by range_insert_aux for forward iterators 2093 template<typename _ForwardIterator> 2094 void 2095 _M_insert_aux(iterator __pos, 2096 _ForwardIterator __first, _ForwardIterator __last, 2097 size_type __n); 2098 2099 2100 // Internal erase functions follow. 2101 2102 void 2103 _M_destroy_data_aux(iterator __first, iterator __last); 2104 2105 // Called by ~deque(). 2106 // NB: Doesn't deallocate the nodes. 2107 template<typename _Alloc1> 2108 void 2109 _M_destroy_data(iterator __first, iterator __last, const _Alloc1&) 2110 { _M_destroy_data_aux(__first, __last); } 2111 2112 void 2113 _M_destroy_data(iterator __first, iterator __last, 2114 const std::allocator<_Tp>&) 2115 { 2116 if (!__has_trivial_destructor(value_type)) 2117 _M_destroy_data_aux(__first, __last); 2118 } 2119 2120 // Called by erase(q1, q2). 2121 void 2122 _M_erase_at_begin(iterator __pos) 2123 { 2124 _M_destroy_data(begin(), __pos, _M_get_Tp_allocator()); 2125 _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node); 2126 this->_M_impl._M_start = __pos; 2127 } 2128 2129 // Called by erase(q1, q2), resize(), clear(), _M_assign_aux, 2130 // _M_fill_assign, operator=. 2131 void 2132 _M_erase_at_end(iterator __pos) 2133 { 2134 _M_destroy_data(__pos, end(), _M_get_Tp_allocator()); 2135 _M_destroy_nodes(__pos._M_node + 1, 2136 this->_M_impl._M_finish._M_node + 1); 2137 this->_M_impl._M_finish = __pos; 2138 } 2139 2140 iterator 2141 _M_erase(iterator __pos); 2142 2143 iterator 2144 _M_erase(iterator __first, iterator __last); 2145 2146 #if __cplusplus >= 201103L 2147 // Called by resize(sz). 2148 void 2149 _M_default_append(size_type __n); 2150 2151 bool 2152 _M_shrink_to_fit(); 2153 #endif 2154 2155 //@{ 2156 /// Memory-handling helpers for the previous internal insert functions. 2157 iterator 2158 _M_reserve_elements_at_front(size_type __n) 2159 { 2160 const size_type __vacancies = this->_M_impl._M_start._M_cur 2161 - this->_M_impl._M_start._M_first; 2162 if (__n > __vacancies) 2163 _M_new_elements_at_front(__n - __vacancies); 2164 return this->_M_impl._M_start - difference_type(__n); 2165 } 2166 2167 iterator 2168 _M_reserve_elements_at_back(size_type __n) 2169 { 2170 const size_type __vacancies = (this->_M_impl._M_finish._M_last 2171 - this->_M_impl._M_finish._M_cur) - 1; 2172 if (__n > __vacancies) 2173 _M_new_elements_at_back(__n - __vacancies); 2174 return this->_M_impl._M_finish + difference_type(__n); 2175 } 2176 2177 void 2178 _M_new_elements_at_front(size_type __new_elements); 2179 2180 void 2181 _M_new_elements_at_back(size_type __new_elements); 2182 //@} 2183 2184 2185 //@{ 2186 /** 2187 * @brief Memory-handling helpers for the major %map. 2188 * 2189 * Makes sure the _M_map has space for new nodes. Does not 2190 * actually add the nodes. Can invalidate _M_map pointers. 2191 * (And consequently, %deque iterators.) 2192 */ 2193 void 2194 _M_reserve_map_at_back(size_type __nodes_to_add = 1) 2195 { 2196 if (__nodes_to_add + 1 > this->_M_impl._M_map_size 2197 - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map)) 2198 _M_reallocate_map(__nodes_to_add, false); 2199 } 2200 2201 void 2202 _M_reserve_map_at_front(size_type __nodes_to_add = 1) 2203 { 2204 if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node 2205 - this->_M_impl._M_map)) 2206 _M_reallocate_map(__nodes_to_add, true); 2207 } 2208 2209 void 2210 _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front); 2211 //@} 2212 2213 #if __cplusplus >= 201103L 2214 // Constant-time, nothrow move assignment when source object's memory 2215 // can be moved because the allocators are equal. 2216 void 2217 _M_move_assign1(deque&& __x, /* always equal: */ true_type) noexcept 2218 { 2219 this->_M_impl._M_swap_data(__x._M_impl); 2220 __x.clear(); 2221 std::__alloc_on_move(_M_get_Tp_allocator(), __x._M_get_Tp_allocator()); 2222 } 2223 2224 // When the allocators are not equal the operation could throw, because 2225 // we might need to allocate a new map for __x after moving from it 2226 // or we might need to allocate new elements for *this. 2227 void 2228 _M_move_assign1(deque&& __x, /* always equal: */ false_type) 2229 { 2230 constexpr bool __move_storage = 2231 _Alloc_traits::_S_propagate_on_move_assign(); 2232 _M_move_assign2(std::move(__x), __bool_constant<__move_storage>()); 2233 } 2234 2235 // Destroy all elements and deallocate all memory, then replace 2236 // with elements created from __args. 2237 template<typename... _Args> 2238 void 2239 _M_replace_map(_Args&&... __args) 2240 { 2241 // Create new data first, so if allocation fails there are no effects. 2242 deque __newobj(std::forward<_Args>(__args)...); 2243 // Free existing storage using existing allocator. 2244 clear(); 2245 _M_deallocate_node(*begin()._M_node); // one node left after clear() 2246 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 2247 this->_M_impl._M_map = nullptr; 2248 this->_M_impl._M_map_size = 0; 2249 // Take ownership of replacement memory. 2250 this->_M_impl._M_swap_data(__newobj._M_impl); 2251 } 2252 2253 // Do move assignment when the allocator propagates. 2254 void 2255 _M_move_assign2(deque&& __x, /* propagate: */ true_type) 2256 { 2257 // Make a copy of the original allocator state. 2258 auto __alloc = __x._M_get_Tp_allocator(); 2259 // The allocator propagates so storage can be moved from __x, 2260 // leaving __x in a valid empty state with a moved-from allocator. 2261 _M_replace_map(std::move(__x)); 2262 // Move the corresponding allocator state too. 2263 _M_get_Tp_allocator() = std::move(__alloc); 2264 } 2265 2266 // Do move assignment when it may not be possible to move source 2267 // object's memory, resulting in a linear-time operation. 2268 void 2269 _M_move_assign2(deque&& __x, /* propagate: */ false_type) 2270 { 2271 if (__x._M_get_Tp_allocator() == this->_M_get_Tp_allocator()) 2272 { 2273 // The allocators are equal so storage can be moved from __x, 2274 // leaving __x in a valid empty state with its current allocator. 2275 _M_replace_map(std::move(__x), __x.get_allocator()); 2276 } 2277 else 2278 { 2279 // The rvalue's allocator cannot be moved and is not equal, 2280 // so we need to individually move each element. 2281 _M_assign_aux(std::__make_move_if_noexcept_iterator(__x.begin()), 2282 std::__make_move_if_noexcept_iterator(__x.end()), 2283 std::random_access_iterator_tag()); 2284 __x.clear(); 2285 } 2286 } 2287 #endif 2288 }; 2289 2290 #if __cpp_deduction_guides >= 201606 2291 template<typename _InputIterator, typename _ValT 2292 = typename iterator_traits<_InputIterator>::value_type, 2293 typename _Allocator = allocator<_ValT>, 2294 typename = _RequireInputIter<_InputIterator>, 2295 typename = _RequireAllocator<_Allocator>> 2296 deque(_InputIterator, _InputIterator, _Allocator = _Allocator()) 2297 -> deque<_ValT, _Allocator>; 2298 #endif 2299 2300 /** 2301 * @brief Deque equality comparison. 2302 * @param __x A %deque. 2303 * @param __y A %deque of the same type as @a __x. 2304 * @return True iff the size and elements of the deques are equal. 2305 * 2306 * This is an equivalence relation. It is linear in the size of the 2307 * deques. Deques are considered equivalent if their sizes are equal, 2308 * and if corresponding elements compare equal. 2309 */ 2310 template<typename _Tp, typename _Alloc> 2311 inline bool 2312 operator==(const deque<_Tp, _Alloc>& __x, 2313 const deque<_Tp, _Alloc>& __y) 2314 { return __x.size() == __y.size() 2315 && std::equal(__x.begin(), __x.end(), __y.begin()); } 2316 2317 /** 2318 * @brief Deque ordering relation. 2319 * @param __x A %deque. 2320 * @param __y A %deque of the same type as @a __x. 2321 * @return True iff @a x is lexicographically less than @a __y. 2322 * 2323 * This is a total ordering relation. It is linear in the size of the 2324 * deques. The elements must be comparable with @c <. 2325 * 2326 * See std::lexicographical_compare() for how the determination is made. 2327 */ 2328 template<typename _Tp, typename _Alloc> 2329 inline bool 2330 operator<(const deque<_Tp, _Alloc>& __x, 2331 const deque<_Tp, _Alloc>& __y) 2332 { return std::lexicographical_compare(__x.begin(), __x.end(), 2333 __y.begin(), __y.end()); } 2334 2335 /// Based on operator== 2336 template<typename _Tp, typename _Alloc> 2337 inline bool 2338 operator!=(const deque<_Tp, _Alloc>& __x, 2339 const deque<_Tp, _Alloc>& __y) 2340 { return !(__x == __y); } 2341 2342 /// Based on operator< 2343 template<typename _Tp, typename _Alloc> 2344 inline bool 2345 operator>(const deque<_Tp, _Alloc>& __x, 2346 const deque<_Tp, _Alloc>& __y) 2347 { return __y < __x; } 2348 2349 /// Based on operator< 2350 template<typename _Tp, typename _Alloc> 2351 inline bool 2352 operator<=(const deque<_Tp, _Alloc>& __x, 2353 const deque<_Tp, _Alloc>& __y) 2354 { return !(__y < __x); } 2355 2356 /// Based on operator< 2357 template<typename _Tp, typename _Alloc> 2358 inline bool 2359 operator>=(const deque<_Tp, _Alloc>& __x, 2360 const deque<_Tp, _Alloc>& __y) 2361 { return !(__x < __y); } 2362 2363 /// See std::deque::swap(). 2364 template<typename _Tp, typename _Alloc> 2365 inline void 2366 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y) 2367 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y))) 2368 { __x.swap(__y); } 2369 2370 #undef _GLIBCXX_DEQUE_BUF_SIZE 2371 2372 _GLIBCXX_END_NAMESPACE_CONTAINER 2373 2374 #if __cplusplus >= 201103L 2375 // std::allocator is safe, but it is not the only allocator 2376 // for which this is valid. 2377 template<class _Tp> 2378 struct __is_bitwise_relocatable<_GLIBCXX_STD_C::deque<_Tp>> 2379 : true_type { }; 2380 #endif 2381 2382 _GLIBCXX_END_NAMESPACE_VERSION 2383 } // namespace std 2384 2385 #endif /* _STL_DEQUE_H */ 2386