1 // Deque implementation -*- C++ -*- 2 3 // Copyright (C) 2001-2018 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 #endif 65 66 #include <debug/assertions.h> 67 68 namespace std _GLIBCXX_VISIBILITY(default) 69 { 70 _GLIBCXX_BEGIN_NAMESPACE_VERSION 71 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER 72 73 /** 74 * @brief This function controls the size of memory nodes. 75 * @param __size The size of an element. 76 * @return The number (not byte size) of elements per node. 77 * 78 * This function started off as a compiler kludge from SGI, but 79 * seems to be a useful wrapper around a repeated constant 80 * expression. The @b 512 is tunable (and no other code needs to 81 * change), but no investigation has been done since inheriting the 82 * SGI code. Touch _GLIBCXX_DEQUE_BUF_SIZE only if you know what 83 * you are doing, however: changing it breaks the binary 84 * compatibility!! 85 */ 86 87 #ifndef _GLIBCXX_DEQUE_BUF_SIZE 88 #define _GLIBCXX_DEQUE_BUF_SIZE 512 89 #endif 90 91 _GLIBCXX_CONSTEXPR inline size_t 92 __deque_buf_size(size_t __size) 93 { return (__size < _GLIBCXX_DEQUE_BUF_SIZE 94 ? size_t(_GLIBCXX_DEQUE_BUF_SIZE / __size) : size_t(1)); } 95 96 97 /** 98 * @brief A deque::iterator. 99 * 100 * Quite a bit of intelligence here. Much of the functionality of 101 * deque is actually passed off to this class. A deque holds two 102 * of these internally, marking its valid range. Access to 103 * elements is done as offsets of either of those two, relying on 104 * operator overloading in this class. 105 * 106 * All the functions are op overloads except for _M_set_node. 107 */ 108 template<typename _Tp, typename _Ref, typename _Ptr> 109 struct _Deque_iterator 110 { 111 #if __cplusplus < 201103L 112 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator; 113 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator; 114 typedef _Tp* _Elt_pointer; 115 typedef _Tp** _Map_pointer; 116 #else 117 private: 118 template<typename _Up> 119 using __ptr_to = typename pointer_traits<_Ptr>::template rebind<_Up>; 120 template<typename _CvTp> 121 using __iter = _Deque_iterator<_Tp, _CvTp&, __ptr_to<_CvTp>>; 122 public: 123 typedef __iter<_Tp> iterator; 124 typedef __iter<const _Tp> const_iterator; 125 typedef __ptr_to<_Tp> _Elt_pointer; 126 typedef __ptr_to<_Elt_pointer> _Map_pointer; 127 #endif 128 129 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 130 { return __deque_buf_size(sizeof(_Tp)); } 131 132 typedef std::random_access_iterator_tag iterator_category; 133 typedef _Tp value_type; 134 typedef _Ptr pointer; 135 typedef _Ref reference; 136 typedef size_t size_type; 137 typedef ptrdiff_t difference_type; 138 typedef _Deque_iterator _Self; 139 140 _Elt_pointer _M_cur; 141 _Elt_pointer _M_first; 142 _Elt_pointer _M_last; 143 _Map_pointer _M_node; 144 145 _Deque_iterator(_Elt_pointer __x, _Map_pointer __y) _GLIBCXX_NOEXCEPT 146 : _M_cur(__x), _M_first(*__y), 147 _M_last(*__y + _S_buffer_size()), _M_node(__y) { } 148 149 _Deque_iterator() _GLIBCXX_NOEXCEPT 150 : _M_cur(), _M_first(), _M_last(), _M_node() { } 151 152 _Deque_iterator(const iterator& __x) _GLIBCXX_NOEXCEPT 153 : _M_cur(__x._M_cur), _M_first(__x._M_first), 154 _M_last(__x._M_last), _M_node(__x._M_node) { } 155 156 iterator 157 _M_const_cast() const _GLIBCXX_NOEXCEPT 158 { return iterator(_M_cur, _M_node); } 159 160 reference 161 operator*() const _GLIBCXX_NOEXCEPT 162 { return *_M_cur; } 163 164 pointer 165 operator->() const _GLIBCXX_NOEXCEPT 166 { return _M_cur; } 167 168 _Self& 169 operator++() _GLIBCXX_NOEXCEPT 170 { 171 ++_M_cur; 172 if (_M_cur == _M_last) 173 { 174 _M_set_node(_M_node + 1); 175 _M_cur = _M_first; 176 } 177 return *this; 178 } 179 180 _Self 181 operator++(int) _GLIBCXX_NOEXCEPT 182 { 183 _Self __tmp = *this; 184 ++*this; 185 return __tmp; 186 } 187 188 _Self& 189 operator--() _GLIBCXX_NOEXCEPT 190 { 191 if (_M_cur == _M_first) 192 { 193 _M_set_node(_M_node - 1); 194 _M_cur = _M_last; 195 } 196 --_M_cur; 197 return *this; 198 } 199 200 _Self 201 operator--(int) _GLIBCXX_NOEXCEPT 202 { 203 _Self __tmp = *this; 204 --*this; 205 return __tmp; 206 } 207 208 _Self& 209 operator+=(difference_type __n) _GLIBCXX_NOEXCEPT 210 { 211 const difference_type __offset = __n + (_M_cur - _M_first); 212 if (__offset >= 0 && __offset < difference_type(_S_buffer_size())) 213 _M_cur += __n; 214 else 215 { 216 const difference_type __node_offset = 217 __offset > 0 ? __offset / difference_type(_S_buffer_size()) 218 : -difference_type((-__offset - 1) 219 / _S_buffer_size()) - 1; 220 _M_set_node(_M_node + __node_offset); 221 _M_cur = _M_first + (__offset - __node_offset 222 * difference_type(_S_buffer_size())); 223 } 224 return *this; 225 } 226 227 _Self 228 operator+(difference_type __n) const _GLIBCXX_NOEXCEPT 229 { 230 _Self __tmp = *this; 231 return __tmp += __n; 232 } 233 234 _Self& 235 operator-=(difference_type __n) _GLIBCXX_NOEXCEPT 236 { return *this += -__n; } 237 238 _Self 239 operator-(difference_type __n) const _GLIBCXX_NOEXCEPT 240 { 241 _Self __tmp = *this; 242 return __tmp -= __n; 243 } 244 245 reference 246 operator[](difference_type __n) const _GLIBCXX_NOEXCEPT 247 { return *(*this + __n); } 248 249 /** 250 * Prepares to traverse new_node. Sets everything except 251 * _M_cur, which should therefore be set by the caller 252 * immediately afterwards, based on _M_first and _M_last. 253 */ 254 void 255 _M_set_node(_Map_pointer __new_node) _GLIBCXX_NOEXCEPT 256 { 257 _M_node = __new_node; 258 _M_first = *__new_node; 259 _M_last = _M_first + difference_type(_S_buffer_size()); 260 } 261 }; 262 263 // Note: we also provide overloads whose operands are of the same type in 264 // order to avoid ambiguous overload resolution when std::rel_ops operators 265 // are in scope (for additional details, see libstdc++/3628) 266 template<typename _Tp, typename _Ref, typename _Ptr> 267 inline bool 268 operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 269 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 270 { return __x._M_cur == __y._M_cur; } 271 272 template<typename _Tp, typename _RefL, typename _PtrL, 273 typename _RefR, typename _PtrR> 274 inline bool 275 operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 276 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 277 { return __x._M_cur == __y._M_cur; } 278 279 template<typename _Tp, typename _Ref, typename _Ptr> 280 inline bool 281 operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 282 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 283 { return !(__x == __y); } 284 285 template<typename _Tp, typename _RefL, typename _PtrL, 286 typename _RefR, typename _PtrR> 287 inline bool 288 operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 289 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 290 { return !(__x == __y); } 291 292 template<typename _Tp, typename _Ref, typename _Ptr> 293 inline bool 294 operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 295 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 296 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 297 : (__x._M_node < __y._M_node); } 298 299 template<typename _Tp, typename _RefL, typename _PtrL, 300 typename _RefR, typename _PtrR> 301 inline bool 302 operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 303 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 304 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 305 : (__x._M_node < __y._M_node); } 306 307 template<typename _Tp, typename _Ref, typename _Ptr> 308 inline bool 309 operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 310 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 311 { return __y < __x; } 312 313 template<typename _Tp, typename _RefL, typename _PtrL, 314 typename _RefR, typename _PtrR> 315 inline bool 316 operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 317 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 318 { return __y < __x; } 319 320 template<typename _Tp, typename _Ref, typename _Ptr> 321 inline bool 322 operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 323 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 324 { return !(__y < __x); } 325 326 template<typename _Tp, typename _RefL, typename _PtrL, 327 typename _RefR, typename _PtrR> 328 inline bool 329 operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 330 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 331 { return !(__y < __x); } 332 333 template<typename _Tp, typename _Ref, typename _Ptr> 334 inline bool 335 operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 336 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 337 { return !(__x < __y); } 338 339 template<typename _Tp, typename _RefL, typename _PtrL, 340 typename _RefR, typename _PtrR> 341 inline bool 342 operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 343 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 344 { return !(__x < __y); } 345 346 // _GLIBCXX_RESOLVE_LIB_DEFECTS 347 // According to the resolution of DR179 not only the various comparison 348 // operators but also operator- must accept mixed iterator/const_iterator 349 // parameters. 350 template<typename _Tp, typename _Ref, typename _Ptr> 351 inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 352 operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 353 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 354 { 355 return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 356 (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size()) 357 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 358 + (__y._M_last - __y._M_cur); 359 } 360 361 template<typename _Tp, typename _RefL, typename _PtrL, 362 typename _RefR, typename _PtrR> 363 inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 364 operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 365 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 366 { 367 return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 368 (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size()) 369 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 370 + (__y._M_last - __y._M_cur); 371 } 372 373 template<typename _Tp, typename _Ref, typename _Ptr> 374 inline _Deque_iterator<_Tp, _Ref, _Ptr> 375 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x) 376 _GLIBCXX_NOEXCEPT 377 { return __x + __n; } 378 379 template<typename _Tp> 380 void 381 fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>&, 382 const _Deque_iterator<_Tp, _Tp&, _Tp*>&, const _Tp&); 383 384 template<typename _Tp> 385 _Deque_iterator<_Tp, _Tp&, _Tp*> 386 copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 387 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 388 _Deque_iterator<_Tp, _Tp&, _Tp*>); 389 390 template<typename _Tp> 391 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 392 copy(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 393 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 394 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 395 { return std::copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 396 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 397 __result); } 398 399 template<typename _Tp> 400 _Deque_iterator<_Tp, _Tp&, _Tp*> 401 copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 402 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 403 _Deque_iterator<_Tp, _Tp&, _Tp*>); 404 405 template<typename _Tp> 406 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 407 copy_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 408 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 409 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 410 { return std::copy_backward(_Deque_iterator<_Tp, 411 const _Tp&, const _Tp*>(__first), 412 _Deque_iterator<_Tp, 413 const _Tp&, const _Tp*>(__last), 414 __result); } 415 416 #if __cplusplus >= 201103L 417 template<typename _Tp> 418 _Deque_iterator<_Tp, _Tp&, _Tp*> 419 move(_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 move(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 426 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 427 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 428 { return std::move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 429 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 430 __result); } 431 432 template<typename _Tp> 433 _Deque_iterator<_Tp, _Tp&, _Tp*> 434 move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 435 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 436 _Deque_iterator<_Tp, _Tp&, _Tp*>); 437 438 template<typename _Tp> 439 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 440 move_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 441 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 442 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 443 { return std::move_backward(_Deque_iterator<_Tp, 444 const _Tp&, const _Tp*>(__first), 445 _Deque_iterator<_Tp, 446 const _Tp&, const _Tp*>(__last), 447 __result); } 448 #endif 449 450 /** 451 * Deque base class. This class provides the unified face for %deque's 452 * allocation. This class's constructor and destructor allocate and 453 * deallocate (but do not initialize) storage. This makes %exception 454 * safety easier. 455 * 456 * Nothing in this class ever constructs or destroys an actual Tp element. 457 * (Deque handles that itself.) Only/All memory management is performed 458 * here. 459 */ 460 template<typename _Tp, typename _Alloc> 461 class _Deque_base 462 { 463 protected: 464 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template 465 rebind<_Tp>::other _Tp_alloc_type; 466 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits; 467 468 #if __cplusplus < 201103L 469 typedef _Tp* _Ptr; 470 typedef const _Tp* _Ptr_const; 471 #else 472 typedef typename _Alloc_traits::pointer _Ptr; 473 typedef typename _Alloc_traits::const_pointer _Ptr_const; 474 #endif 475 476 typedef typename _Alloc_traits::template rebind<_Ptr>::other 477 _Map_alloc_type; 478 typedef __gnu_cxx::__alloc_traits<_Map_alloc_type> _Map_alloc_traits; 479 480 public: 481 typedef _Alloc allocator_type; 482 typedef typename _Alloc_traits::size_type size_type; 483 484 allocator_type 485 get_allocator() const _GLIBCXX_NOEXCEPT 486 { return allocator_type(_M_get_Tp_allocator()); } 487 488 typedef _Deque_iterator<_Tp, _Tp&, _Ptr> iterator; 489 typedef _Deque_iterator<_Tp, const _Tp&, _Ptr_const> const_iterator; 490 491 _Deque_base() 492 : _M_impl() 493 { _M_initialize_map(0); } 494 495 _Deque_base(size_t __num_elements) 496 : _M_impl() 497 { _M_initialize_map(__num_elements); } 498 499 _Deque_base(const allocator_type& __a, size_t __num_elements) 500 : _M_impl(__a) 501 { _M_initialize_map(__num_elements); } 502 503 _Deque_base(const allocator_type& __a) 504 : _M_impl(__a) 505 { /* Caller must initialize map. */ } 506 507 #if __cplusplus >= 201103L 508 _Deque_base(_Deque_base&& __x, false_type) 509 : _M_impl(__x._M_move_impl()) 510 { } 511 512 _Deque_base(_Deque_base&& __x, true_type) 513 : _M_impl(std::move(__x._M_get_Tp_allocator())) 514 { 515 _M_initialize_map(0); 516 if (__x._M_impl._M_map) 517 this->_M_impl._M_swap_data(__x._M_impl); 518 } 519 520 _Deque_base(_Deque_base&& __x) 521 : _Deque_base(std::move(__x), typename _Alloc_traits::is_always_equal{}) 522 { } 523 524 _Deque_base(_Deque_base&& __x, const allocator_type& __a, size_type __n) 525 : _M_impl(__a) 526 { 527 if (__x.get_allocator() == __a) 528 { 529 if (__x._M_impl._M_map) 530 { 531 _M_initialize_map(0); 532 this->_M_impl._M_swap_data(__x._M_impl); 533 } 534 } 535 else 536 { 537 _M_initialize_map(__n); 538 } 539 } 540 #endif 541 542 ~_Deque_base() _GLIBCXX_NOEXCEPT; 543 544 protected: 545 typedef typename iterator::_Map_pointer _Map_pointer; 546 547 //This struct encapsulates the implementation of the std::deque 548 //standard container and at the same time makes use of the EBO 549 //for empty allocators. 550 struct _Deque_impl 551 : public _Tp_alloc_type 552 { 553 _Map_pointer _M_map; 554 size_t _M_map_size; 555 iterator _M_start; 556 iterator _M_finish; 557 558 _Deque_impl() 559 : _Tp_alloc_type(), _M_map(), _M_map_size(0), 560 _M_start(), _M_finish() 561 { } 562 563 _Deque_impl(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT 564 : _Tp_alloc_type(__a), _M_map(), _M_map_size(0), 565 _M_start(), _M_finish() 566 { } 567 568 #if __cplusplus >= 201103L 569 _Deque_impl(_Deque_impl&&) = default; 570 571 _Deque_impl(_Tp_alloc_type&& __a) noexcept 572 : _Tp_alloc_type(std::move(__a)), _M_map(), _M_map_size(0), 573 _M_start(), _M_finish() 574 { } 575 #endif 576 577 void _M_swap_data(_Deque_impl& __x) _GLIBCXX_NOEXCEPT 578 { 579 using std::swap; 580 swap(this->_M_start, __x._M_start); 581 swap(this->_M_finish, __x._M_finish); 582 swap(this->_M_map, __x._M_map); 583 swap(this->_M_map_size, __x._M_map_size); 584 } 585 }; 586 587 _Tp_alloc_type& 588 _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT 589 { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); } 590 591 const _Tp_alloc_type& 592 _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT 593 { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); } 594 595 _Map_alloc_type 596 _M_get_map_allocator() const _GLIBCXX_NOEXCEPT 597 { return _Map_alloc_type(_M_get_Tp_allocator()); } 598 599 _Ptr 600 _M_allocate_node() 601 { 602 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 603 return _Traits::allocate(_M_impl, __deque_buf_size(sizeof(_Tp))); 604 } 605 606 void 607 _M_deallocate_node(_Ptr __p) _GLIBCXX_NOEXCEPT 608 { 609 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 610 _Traits::deallocate(_M_impl, __p, __deque_buf_size(sizeof(_Tp))); 611 } 612 613 _Map_pointer 614 _M_allocate_map(size_t __n) 615 { 616 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 617 return _Map_alloc_traits::allocate(__map_alloc, __n); 618 } 619 620 void 621 _M_deallocate_map(_Map_pointer __p, size_t __n) _GLIBCXX_NOEXCEPT 622 { 623 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 624 _Map_alloc_traits::deallocate(__map_alloc, __p, __n); 625 } 626 627 protected: 628 void _M_initialize_map(size_t); 629 void _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish); 630 void _M_destroy_nodes(_Map_pointer __nstart, 631 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT; 632 enum { _S_initial_map_size = 8 }; 633 634 _Deque_impl _M_impl; 635 636 #if __cplusplus >= 201103L 637 private: 638 _Deque_impl 639 _M_move_impl() 640 { 641 if (!_M_impl._M_map) 642 return std::move(_M_impl); 643 644 // Create a copy of the current allocator. 645 _Tp_alloc_type __alloc{_M_get_Tp_allocator()}; 646 // Put that copy in a moved-from state. 647 _Tp_alloc_type __sink __attribute((__unused__)) {std::move(__alloc)}; 648 // Create an empty map that allocates using the moved-from allocator. 649 _Deque_base __empty{__alloc}; 650 __empty._M_initialize_map(0); 651 // Now safe to modify current allocator and perform non-throwing swaps. 652 _Deque_impl __ret{std::move(_M_get_Tp_allocator())}; 653 _M_impl._M_swap_data(__ret); 654 _M_impl._M_swap_data(__empty._M_impl); 655 return __ret; 656 } 657 #endif 658 }; 659 660 template<typename _Tp, typename _Alloc> 661 _Deque_base<_Tp, _Alloc>:: 662 ~_Deque_base() _GLIBCXX_NOEXCEPT 663 { 664 if (this->_M_impl._M_map) 665 { 666 _M_destroy_nodes(this->_M_impl._M_start._M_node, 667 this->_M_impl._M_finish._M_node + 1); 668 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 669 } 670 } 671 672 /** 673 * @brief Layout storage. 674 * @param __num_elements The count of T's for which to allocate space 675 * at first. 676 * @return Nothing. 677 * 678 * The initial underlying memory layout is a bit complicated... 679 */ 680 template<typename _Tp, typename _Alloc> 681 void 682 _Deque_base<_Tp, _Alloc>:: 683 _M_initialize_map(size_t __num_elements) 684 { 685 const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp)) 686 + 1); 687 688 this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size, 689 size_t(__num_nodes + 2)); 690 this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size); 691 692 // For "small" maps (needing less than _M_map_size nodes), allocation 693 // starts in the middle elements and grows outwards. So nstart may be 694 // the beginning of _M_map, but for small maps it may be as far in as 695 // _M_map+3. 696 697 _Map_pointer __nstart = (this->_M_impl._M_map 698 + (this->_M_impl._M_map_size - __num_nodes) / 2); 699 _Map_pointer __nfinish = __nstart + __num_nodes; 700 701 __try 702 { _M_create_nodes(__nstart, __nfinish); } 703 __catch(...) 704 { 705 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 706 this->_M_impl._M_map = _Map_pointer(); 707 this->_M_impl._M_map_size = 0; 708 __throw_exception_again; 709 } 710 711 this->_M_impl._M_start._M_set_node(__nstart); 712 this->_M_impl._M_finish._M_set_node(__nfinish - 1); 713 this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first; 714 this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first 715 + __num_elements 716 % __deque_buf_size(sizeof(_Tp))); 717 } 718 719 template<typename _Tp, typename _Alloc> 720 void 721 _Deque_base<_Tp, _Alloc>:: 722 _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish) 723 { 724 _Map_pointer __cur; 725 __try 726 { 727 for (__cur = __nstart; __cur < __nfinish; ++__cur) 728 *__cur = this->_M_allocate_node(); 729 } 730 __catch(...) 731 { 732 _M_destroy_nodes(__nstart, __cur); 733 __throw_exception_again; 734 } 735 } 736 737 template<typename _Tp, typename _Alloc> 738 void 739 _Deque_base<_Tp, _Alloc>:: 740 _M_destroy_nodes(_Map_pointer __nstart, 741 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT 742 { 743 for (_Map_pointer __n = __nstart; __n < __nfinish; ++__n) 744 _M_deallocate_node(*__n); 745 } 746 747 /** 748 * @brief A standard container using fixed-size memory allocation and 749 * constant-time manipulation of elements at either end. 750 * 751 * @ingroup sequences 752 * 753 * @tparam _Tp Type of element. 754 * @tparam _Alloc Allocator type, defaults to allocator<_Tp>. 755 * 756 * Meets the requirements of a <a href="tables.html#65">container</a>, a 757 * <a href="tables.html#66">reversible container</a>, and a 758 * <a href="tables.html#67">sequence</a>, including the 759 * <a href="tables.html#68">optional sequence requirements</a>. 760 * 761 * In previous HP/SGI versions of deque, there was an extra template 762 * parameter so users could control the node size. This extension turned 763 * out to violate the C++ standard (it can be detected using template 764 * template parameters), and it was removed. 765 * 766 * Here's how a deque<Tp> manages memory. Each deque has 4 members: 767 * 768 * - Tp** _M_map 769 * - size_t _M_map_size 770 * - iterator _M_start, _M_finish 771 * 772 * map_size is at least 8. %map is an array of map_size 773 * pointers-to-@a nodes. (The name %map has nothing to do with the 774 * std::map class, and @b nodes should not be confused with 775 * std::list's usage of @a node.) 776 * 777 * A @a node has no specific type name as such, but it is referred 778 * to as @a node in this file. It is a simple array-of-Tp. If Tp 779 * is very large, there will be one Tp element per node (i.e., an 780 * @a array of one). For non-huge Tp's, node size is inversely 781 * related to Tp size: the larger the Tp, the fewer Tp's will fit 782 * in a node. The goal here is to keep the total size of a node 783 * relatively small and constant over different Tp's, to improve 784 * allocator efficiency. 785 * 786 * Not every pointer in the %map array will point to a node. If 787 * the initial number of elements in the deque is small, the 788 * /middle/ %map pointers will be valid, and the ones at the edges 789 * will be unused. This same situation will arise as the %map 790 * grows: available %map pointers, if any, will be on the ends. As 791 * new nodes are created, only a subset of the %map's pointers need 792 * to be copied @a outward. 793 * 794 * Class invariants: 795 * - For any nonsingular iterator i: 796 * - i.node points to a member of the %map array. (Yes, you read that 797 * correctly: i.node does not actually point to a node.) The member of 798 * the %map array is what actually points to the node. 799 * - i.first == *(i.node) (This points to the node (first Tp element).) 800 * - i.last == i.first + node_size 801 * - i.cur is a pointer in the range [i.first, i.last). NOTE: 802 * the implication of this is that i.cur is always a dereferenceable 803 * pointer, even if i is a past-the-end iterator. 804 * - Start and Finish are always nonsingular iterators. NOTE: this 805 * means that an empty deque must have one node, a deque with <N 806 * elements (where N is the node buffer size) must have one node, a 807 * deque with N through (2N-1) elements must have two nodes, etc. 808 * - For every node other than start.node and finish.node, every 809 * element in the node is an initialized object. If start.node == 810 * finish.node, then [start.cur, finish.cur) are initialized 811 * objects, and the elements outside that range are uninitialized 812 * storage. Otherwise, [start.cur, start.last) and [finish.first, 813 * finish.cur) are initialized objects, and [start.first, start.cur) 814 * and [finish.cur, finish.last) are uninitialized storage. 815 * - [%map, %map + map_size) is a valid, non-empty range. 816 * - [start.node, finish.node] is a valid range contained within 817 * [%map, %map + map_size). 818 * - A pointer in the range [%map, %map + map_size) points to an allocated 819 * node if and only if the pointer is in the range 820 * [start.node, finish.node]. 821 * 822 * Here's the magic: nothing in deque is @b aware of the discontiguous 823 * storage! 824 * 825 * The memory setup and layout occurs in the parent, _Base, and the iterator 826 * class is entirely responsible for @a leaping from one node to the next. 827 * All the implementation routines for deque itself work only through the 828 * start and finish iterators. This keeps the routines simple and sane, 829 * and we can use other standard algorithms as well. 830 */ 831 template<typename _Tp, typename _Alloc = std::allocator<_Tp> > 832 class deque : protected _Deque_base<_Tp, _Alloc> 833 { 834 #ifdef _GLIBCXX_CONCEPT_CHECKS 835 // concept requirements 836 typedef typename _Alloc::value_type _Alloc_value_type; 837 # if __cplusplus < 201103L 838 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 839 # endif 840 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept) 841 #endif 842 843 #if __cplusplus >= 201103L 844 static_assert(is_same<typename remove_cv<_Tp>::type, _Tp>::value, 845 "std::deque must have a non-const, non-volatile value_type"); 846 # ifdef __STRICT_ANSI__ 847 static_assert(is_same<typename _Alloc::value_type, _Tp>::value, 848 "std::deque must have the same value_type as its allocator"); 849 # endif 850 #endif 851 852 typedef _Deque_base<_Tp, _Alloc> _Base; 853 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type; 854 typedef typename _Base::_Alloc_traits _Alloc_traits; 855 typedef typename _Base::_Map_pointer _Map_pointer; 856 857 public: 858 typedef _Tp value_type; 859 typedef typename _Alloc_traits::pointer pointer; 860 typedef typename _Alloc_traits::const_pointer const_pointer; 861 typedef typename _Alloc_traits::reference reference; 862 typedef typename _Alloc_traits::const_reference const_reference; 863 typedef typename _Base::iterator iterator; 864 typedef typename _Base::const_iterator const_iterator; 865 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 866 typedef std::reverse_iterator<iterator> reverse_iterator; 867 typedef size_t size_type; 868 typedef ptrdiff_t difference_type; 869 typedef _Alloc allocator_type; 870 871 protected: 872 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 873 { return __deque_buf_size(sizeof(_Tp)); } 874 875 // Functions controlling memory layout, and nothing else. 876 using _Base::_M_initialize_map; 877 using _Base::_M_create_nodes; 878 using _Base::_M_destroy_nodes; 879 using _Base::_M_allocate_node; 880 using _Base::_M_deallocate_node; 881 using _Base::_M_allocate_map; 882 using _Base::_M_deallocate_map; 883 using _Base::_M_get_Tp_allocator; 884 885 /** 886 * A total of four data members accumulated down the hierarchy. 887 * May be accessed via _M_impl.* 888 */ 889 using _Base::_M_impl; 890 891 public: 892 // [23.2.1.1] construct/copy/destroy 893 // (assign() and get_allocator() are also listed in this section) 894 895 /** 896 * @brief Creates a %deque with no elements. 897 */ 898 deque() : _Base() { } 899 900 /** 901 * @brief Creates a %deque with no elements. 902 * @param __a An allocator object. 903 */ 904 explicit 905 deque(const allocator_type& __a) 906 : _Base(__a, 0) { } 907 908 #if __cplusplus >= 201103L 909 /** 910 * @brief Creates a %deque with default constructed elements. 911 * @param __n The number of elements to initially create. 912 * @param __a An allocator. 913 * 914 * This constructor fills the %deque with @a n default 915 * constructed elements. 916 */ 917 explicit 918 deque(size_type __n, const allocator_type& __a = allocator_type()) 919 : _Base(__a, __n) 920 { _M_default_initialize(); } 921 922 /** 923 * @brief Creates a %deque with copies of an exemplar element. 924 * @param __n The number of elements to initially create. 925 * @param __value An element to copy. 926 * @param __a An allocator. 927 * 928 * This constructor fills the %deque with @a __n copies of @a __value. 929 */ 930 deque(size_type __n, const value_type& __value, 931 const allocator_type& __a = allocator_type()) 932 : _Base(__a, __n) 933 { _M_fill_initialize(__value); } 934 #else 935 /** 936 * @brief Creates a %deque with copies of an exemplar element. 937 * @param __n The number of elements to initially create. 938 * @param __value An element to copy. 939 * @param __a An allocator. 940 * 941 * This constructor fills the %deque with @a __n copies of @a __value. 942 */ 943 explicit 944 deque(size_type __n, const value_type& __value = value_type(), 945 const allocator_type& __a = allocator_type()) 946 : _Base(__a, __n) 947 { _M_fill_initialize(__value); } 948 #endif 949 950 /** 951 * @brief %Deque copy constructor. 952 * @param __x A %deque of identical element and allocator types. 953 * 954 * The newly-created %deque uses a copy of the allocator object used 955 * by @a __x (unless the allocator traits dictate a different object). 956 */ 957 deque(const deque& __x) 958 : _Base(_Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()), 959 __x.size()) 960 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 961 this->_M_impl._M_start, 962 _M_get_Tp_allocator()); } 963 964 #if __cplusplus >= 201103L 965 /** 966 * @brief %Deque move constructor. 967 * @param __x A %deque of identical element and allocator types. 968 * 969 * The newly-created %deque contains the exact contents of @a __x. 970 * The contents of @a __x are a valid, but unspecified %deque. 971 */ 972 deque(deque&& __x) 973 : _Base(std::move(__x)) { } 974 975 /// Copy constructor with alternative allocator 976 deque(const deque& __x, const allocator_type& __a) 977 : _Base(__a, __x.size()) 978 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 979 this->_M_impl._M_start, 980 _M_get_Tp_allocator()); } 981 982 /// Move constructor with alternative allocator 983 deque(deque&& __x, const allocator_type& __a) 984 : _Base(std::move(__x), __a, __x.size()) 985 { 986 if (__x.get_allocator() != __a) 987 { 988 std::__uninitialized_move_a(__x.begin(), __x.end(), 989 this->_M_impl._M_start, 990 _M_get_Tp_allocator()); 991 __x.clear(); 992 } 993 } 994 995 /** 996 * @brief Builds a %deque from an initializer list. 997 * @param __l An initializer_list. 998 * @param __a An allocator object. 999 * 1000 * Create a %deque consisting of copies of the elements in the 1001 * initializer_list @a __l. 1002 * 1003 * This will call the element type's copy constructor N times 1004 * (where N is __l.size()) and do no memory reallocation. 1005 */ 1006 deque(initializer_list<value_type> __l, 1007 const allocator_type& __a = allocator_type()) 1008 : _Base(__a) 1009 { 1010 _M_range_initialize(__l.begin(), __l.end(), 1011 random_access_iterator_tag()); 1012 } 1013 #endif 1014 1015 /** 1016 * @brief Builds a %deque from a range. 1017 * @param __first An input iterator. 1018 * @param __last An input iterator. 1019 * @param __a An allocator object. 1020 * 1021 * Create a %deque consisting of copies of the elements from [__first, 1022 * __last). 1023 * 1024 * If the iterators are forward, bidirectional, or random-access, then 1025 * this will call the elements' copy constructor N times (where N is 1026 * distance(__first,__last)) and do no memory reallocation. But if only 1027 * input iterators are used, then this will do at most 2N calls to the 1028 * copy constructor, and logN memory reallocations. 1029 */ 1030 #if __cplusplus >= 201103L 1031 template<typename _InputIterator, 1032 typename = std::_RequireInputIter<_InputIterator>> 1033 deque(_InputIterator __first, _InputIterator __last, 1034 const allocator_type& __a = allocator_type()) 1035 : _Base(__a) 1036 { _M_initialize_dispatch(__first, __last, __false_type()); } 1037 #else 1038 template<typename _InputIterator> 1039 deque(_InputIterator __first, _InputIterator __last, 1040 const allocator_type& __a = allocator_type()) 1041 : _Base(__a) 1042 { 1043 // Check whether it's an integral type. If so, it's not an iterator. 1044 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1045 _M_initialize_dispatch(__first, __last, _Integral()); 1046 } 1047 #endif 1048 1049 /** 1050 * The dtor only erases the elements, and note that if the elements 1051 * themselves are pointers, the pointed-to memory is not touched in any 1052 * way. Managing the pointer is the user's responsibility. 1053 */ 1054 ~deque() 1055 { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); } 1056 1057 /** 1058 * @brief %Deque assignment operator. 1059 * @param __x A %deque of identical element and allocator types. 1060 * 1061 * All the elements of @a x are copied. 1062 * 1063 * The newly-created %deque uses a copy of the allocator object used 1064 * by @a __x (unless the allocator traits dictate a different object). 1065 */ 1066 deque& 1067 operator=(const deque& __x); 1068 1069 #if __cplusplus >= 201103L 1070 /** 1071 * @brief %Deque move assignment operator. 1072 * @param __x A %deque of identical element and allocator types. 1073 * 1074 * The contents of @a __x are moved into this deque (without copying, 1075 * if the allocators permit it). 1076 * @a __x is a valid, but unspecified %deque. 1077 */ 1078 deque& 1079 operator=(deque&& __x) noexcept(_Alloc_traits::_S_always_equal()) 1080 { 1081 using __always_equal = typename _Alloc_traits::is_always_equal; 1082 _M_move_assign1(std::move(__x), __always_equal{}); 1083 return *this; 1084 } 1085 1086 /** 1087 * @brief Assigns an initializer list to a %deque. 1088 * @param __l An initializer_list. 1089 * 1090 * This function fills a %deque with copies of the elements in the 1091 * initializer_list @a __l. 1092 * 1093 * Note that the assignment completely changes the %deque and that the 1094 * resulting %deque's size is the same as the number of elements 1095 * assigned. 1096 */ 1097 deque& 1098 operator=(initializer_list<value_type> __l) 1099 { 1100 _M_assign_aux(__l.begin(), __l.end(), 1101 random_access_iterator_tag()); 1102 return *this; 1103 } 1104 #endif 1105 1106 /** 1107 * @brief Assigns a given value to a %deque. 1108 * @param __n Number of elements to be assigned. 1109 * @param __val Value to be assigned. 1110 * 1111 * This function fills a %deque with @a n copies of the given 1112 * value. Note that the assignment completely changes the 1113 * %deque and that the resulting %deque's size is the same as 1114 * the number of elements assigned. 1115 */ 1116 void 1117 assign(size_type __n, const value_type& __val) 1118 { _M_fill_assign(__n, __val); } 1119 1120 /** 1121 * @brief Assigns a range to a %deque. 1122 * @param __first An input iterator. 1123 * @param __last An input iterator. 1124 * 1125 * This function fills a %deque with copies of the elements in the 1126 * range [__first,__last). 1127 * 1128 * Note that the assignment completely changes the %deque and that the 1129 * resulting %deque's size is the same as the number of elements 1130 * assigned. 1131 */ 1132 #if __cplusplus >= 201103L 1133 template<typename _InputIterator, 1134 typename = std::_RequireInputIter<_InputIterator>> 1135 void 1136 assign(_InputIterator __first, _InputIterator __last) 1137 { _M_assign_dispatch(__first, __last, __false_type()); } 1138 #else 1139 template<typename _InputIterator> 1140 void 1141 assign(_InputIterator __first, _InputIterator __last) 1142 { 1143 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1144 _M_assign_dispatch(__first, __last, _Integral()); 1145 } 1146 #endif 1147 1148 #if __cplusplus >= 201103L 1149 /** 1150 * @brief Assigns an initializer list to a %deque. 1151 * @param __l An initializer_list. 1152 * 1153 * This function fills a %deque with copies of the elements in the 1154 * initializer_list @a __l. 1155 * 1156 * Note that the assignment completely changes the %deque and that the 1157 * resulting %deque's size is the same as the number of elements 1158 * assigned. 1159 */ 1160 void 1161 assign(initializer_list<value_type> __l) 1162 { _M_assign_aux(__l.begin(), __l.end(), random_access_iterator_tag()); } 1163 #endif 1164 1165 /// Get a copy of the memory allocation object. 1166 allocator_type 1167 get_allocator() const _GLIBCXX_NOEXCEPT 1168 { return _Base::get_allocator(); } 1169 1170 // iterators 1171 /** 1172 * Returns a read/write iterator that points to the first element in the 1173 * %deque. Iteration is done in ordinary element order. 1174 */ 1175 iterator 1176 begin() _GLIBCXX_NOEXCEPT 1177 { return this->_M_impl._M_start; } 1178 1179 /** 1180 * Returns a read-only (constant) iterator that points to the first 1181 * element in the %deque. Iteration is done in ordinary element order. 1182 */ 1183 const_iterator 1184 begin() const _GLIBCXX_NOEXCEPT 1185 { return this->_M_impl._M_start; } 1186 1187 /** 1188 * Returns a read/write iterator that points one past the last 1189 * element in the %deque. Iteration is done in ordinary 1190 * element order. 1191 */ 1192 iterator 1193 end() _GLIBCXX_NOEXCEPT 1194 { return this->_M_impl._M_finish; } 1195 1196 /** 1197 * Returns a read-only (constant) iterator that points one past 1198 * the last element in the %deque. Iteration is done in 1199 * ordinary element order. 1200 */ 1201 const_iterator 1202 end() const _GLIBCXX_NOEXCEPT 1203 { return this->_M_impl._M_finish; } 1204 1205 /** 1206 * Returns a read/write reverse iterator that points to the 1207 * last element in the %deque. Iteration is done in reverse 1208 * element order. 1209 */ 1210 reverse_iterator 1211 rbegin() _GLIBCXX_NOEXCEPT 1212 { return reverse_iterator(this->_M_impl._M_finish); } 1213 1214 /** 1215 * Returns a read-only (constant) reverse iterator that points 1216 * to the last element in the %deque. Iteration is done in 1217 * reverse element order. 1218 */ 1219 const_reverse_iterator 1220 rbegin() const _GLIBCXX_NOEXCEPT 1221 { return const_reverse_iterator(this->_M_impl._M_finish); } 1222 1223 /** 1224 * Returns a read/write reverse iterator that points to one 1225 * before the first element in the %deque. Iteration is done 1226 * in reverse element order. 1227 */ 1228 reverse_iterator 1229 rend() _GLIBCXX_NOEXCEPT 1230 { return reverse_iterator(this->_M_impl._M_start); } 1231 1232 /** 1233 * Returns a read-only (constant) reverse iterator that points 1234 * to one before the first element in the %deque. Iteration is 1235 * done in reverse element order. 1236 */ 1237 const_reverse_iterator 1238 rend() const _GLIBCXX_NOEXCEPT 1239 { return const_reverse_iterator(this->_M_impl._M_start); } 1240 1241 #if __cplusplus >= 201103L 1242 /** 1243 * Returns a read-only (constant) iterator that points to the first 1244 * element in the %deque. Iteration is done in ordinary element order. 1245 */ 1246 const_iterator 1247 cbegin() const noexcept 1248 { return this->_M_impl._M_start; } 1249 1250 /** 1251 * Returns a read-only (constant) iterator that points one past 1252 * the last element in the %deque. Iteration is done in 1253 * ordinary element order. 1254 */ 1255 const_iterator 1256 cend() const noexcept 1257 { return this->_M_impl._M_finish; } 1258 1259 /** 1260 * Returns a read-only (constant) reverse iterator that points 1261 * to the last element in the %deque. Iteration is done in 1262 * reverse element order. 1263 */ 1264 const_reverse_iterator 1265 crbegin() const noexcept 1266 { return const_reverse_iterator(this->_M_impl._M_finish); } 1267 1268 /** 1269 * Returns a read-only (constant) reverse iterator that points 1270 * to one before the first element in the %deque. Iteration is 1271 * done in reverse element order. 1272 */ 1273 const_reverse_iterator 1274 crend() const noexcept 1275 { return const_reverse_iterator(this->_M_impl._M_start); } 1276 #endif 1277 1278 // [23.2.1.2] capacity 1279 /** Returns the number of elements in the %deque. */ 1280 size_type 1281 size() const _GLIBCXX_NOEXCEPT 1282 { return this->_M_impl._M_finish - this->_M_impl._M_start; } 1283 1284 /** Returns the size() of the largest possible %deque. */ 1285 size_type 1286 max_size() const _GLIBCXX_NOEXCEPT 1287 { return _Alloc_traits::max_size(_M_get_Tp_allocator()); } 1288 1289 #if __cplusplus >= 201103L 1290 /** 1291 * @brief Resizes the %deque to the specified number of elements. 1292 * @param __new_size Number of elements the %deque should contain. 1293 * 1294 * This function will %resize the %deque to the specified 1295 * number of elements. If the number is smaller than the 1296 * %deque's current size the %deque is truncated, otherwise 1297 * default constructed elements are appended. 1298 */ 1299 void 1300 resize(size_type __new_size) 1301 { 1302 const size_type __len = size(); 1303 if (__new_size > __len) 1304 _M_default_append(__new_size - __len); 1305 else if (__new_size < __len) 1306 _M_erase_at_end(this->_M_impl._M_start 1307 + difference_type(__new_size)); 1308 } 1309 1310 /** 1311 * @brief Resizes the %deque to the specified number of elements. 1312 * @param __new_size Number of elements the %deque should contain. 1313 * @param __x Data with which new elements should be populated. 1314 * 1315 * This function will %resize the %deque to the specified 1316 * number of elements. If the number is smaller than the 1317 * %deque's current size the %deque is truncated, otherwise the 1318 * %deque is extended and new elements are populated with given 1319 * data. 1320 */ 1321 void 1322 resize(size_type __new_size, const value_type& __x) 1323 { 1324 const size_type __len = size(); 1325 if (__new_size > __len) 1326 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1327 else if (__new_size < __len) 1328 _M_erase_at_end(this->_M_impl._M_start 1329 + difference_type(__new_size)); 1330 } 1331 #else 1332 /** 1333 * @brief Resizes the %deque to the specified number of elements. 1334 * @param __new_size Number of elements the %deque should contain. 1335 * @param __x Data with which new elements should be populated. 1336 * 1337 * This function will %resize the %deque to the specified 1338 * number of elements. If the number is smaller than the 1339 * %deque's current size the %deque is truncated, otherwise the 1340 * %deque is extended and new elements are populated with given 1341 * data. 1342 */ 1343 void 1344 resize(size_type __new_size, value_type __x = value_type()) 1345 { 1346 const size_type __len = size(); 1347 if (__new_size > __len) 1348 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1349 else if (__new_size < __len) 1350 _M_erase_at_end(this->_M_impl._M_start 1351 + difference_type(__new_size)); 1352 } 1353 #endif 1354 1355 #if __cplusplus >= 201103L 1356 /** A non-binding request to reduce memory use. */ 1357 void 1358 shrink_to_fit() noexcept 1359 { _M_shrink_to_fit(); } 1360 #endif 1361 1362 /** 1363 * Returns true if the %deque is empty. (Thus begin() would 1364 * equal end().) 1365 */ 1366 bool 1367 empty() const _GLIBCXX_NOEXCEPT 1368 { return this->_M_impl._M_finish == this->_M_impl._M_start; } 1369 1370 // element access 1371 /** 1372 * @brief Subscript access to the data contained in the %deque. 1373 * @param __n The index of the element for which data should be 1374 * accessed. 1375 * @return Read/write reference to data. 1376 * 1377 * This operator allows for easy, array-style, data access. 1378 * Note that data access with this operator is unchecked and 1379 * out_of_range lookups are not defined. (For checked lookups 1380 * see at().) 1381 */ 1382 reference 1383 operator[](size_type __n) _GLIBCXX_NOEXCEPT 1384 { 1385 __glibcxx_requires_subscript(__n); 1386 return this->_M_impl._M_start[difference_type(__n)]; 1387 } 1388 1389 /** 1390 * @brief Subscript access to the data contained in the %deque. 1391 * @param __n The index of the element for which data should be 1392 * accessed. 1393 * @return Read-only (constant) reference to data. 1394 * 1395 * This operator allows for easy, array-style, data access. 1396 * Note that data access with this operator is unchecked and 1397 * out_of_range lookups are not defined. (For checked lookups 1398 * see at().) 1399 */ 1400 const_reference 1401 operator[](size_type __n) const _GLIBCXX_NOEXCEPT 1402 { 1403 __glibcxx_requires_subscript(__n); 1404 return this->_M_impl._M_start[difference_type(__n)]; 1405 } 1406 1407 protected: 1408 /// Safety check used only from at(). 1409 void 1410 _M_range_check(size_type __n) const 1411 { 1412 if (__n >= this->size()) 1413 __throw_out_of_range_fmt(__N("deque::_M_range_check: __n " 1414 "(which is %zu)>= this->size() " 1415 "(which is %zu)"), 1416 __n, this->size()); 1417 } 1418 1419 public: 1420 /** 1421 * @brief Provides access to the data contained in the %deque. 1422 * @param __n The index of the element for which data should be 1423 * accessed. 1424 * @return Read/write reference to data. 1425 * @throw std::out_of_range If @a __n is an invalid index. 1426 * 1427 * This function provides for safer data access. The parameter 1428 * is first checked that it is in the range of the deque. The 1429 * function throws out_of_range if the check fails. 1430 */ 1431 reference 1432 at(size_type __n) 1433 { 1434 _M_range_check(__n); 1435 return (*this)[__n]; 1436 } 1437 1438 /** 1439 * @brief Provides access to the data contained in the %deque. 1440 * @param __n The index of the element for which data should be 1441 * accessed. 1442 * @return Read-only (constant) reference to data. 1443 * @throw std::out_of_range If @a __n is an invalid index. 1444 * 1445 * This function provides for safer data access. The parameter is first 1446 * checked that it is in the range of the deque. The function throws 1447 * out_of_range if the check fails. 1448 */ 1449 const_reference 1450 at(size_type __n) const 1451 { 1452 _M_range_check(__n); 1453 return (*this)[__n]; 1454 } 1455 1456 /** 1457 * Returns a read/write reference to the data at the first 1458 * element of the %deque. 1459 */ 1460 reference 1461 front() _GLIBCXX_NOEXCEPT 1462 { 1463 __glibcxx_requires_nonempty(); 1464 return *begin(); 1465 } 1466 1467 /** 1468 * Returns a read-only (constant) reference to the data at the first 1469 * element of the %deque. 1470 */ 1471 const_reference 1472 front() const _GLIBCXX_NOEXCEPT 1473 { 1474 __glibcxx_requires_nonempty(); 1475 return *begin(); 1476 } 1477 1478 /** 1479 * Returns a read/write reference to the data at the last element of the 1480 * %deque. 1481 */ 1482 reference 1483 back() _GLIBCXX_NOEXCEPT 1484 { 1485 __glibcxx_requires_nonempty(); 1486 iterator __tmp = end(); 1487 --__tmp; 1488 return *__tmp; 1489 } 1490 1491 /** 1492 * Returns a read-only (constant) reference to the data at the last 1493 * element of the %deque. 1494 */ 1495 const_reference 1496 back() const _GLIBCXX_NOEXCEPT 1497 { 1498 __glibcxx_requires_nonempty(); 1499 const_iterator __tmp = end(); 1500 --__tmp; 1501 return *__tmp; 1502 } 1503 1504 // [23.2.1.2] modifiers 1505 /** 1506 * @brief Add data to the front of the %deque. 1507 * @param __x Data to be added. 1508 * 1509 * This is a typical stack operation. The function creates an 1510 * element at the front of the %deque and assigns the given 1511 * data to it. Due to the nature of a %deque this operation 1512 * can be done in constant time. 1513 */ 1514 void 1515 push_front(const value_type& __x) 1516 { 1517 if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first) 1518 { 1519 _Alloc_traits::construct(this->_M_impl, 1520 this->_M_impl._M_start._M_cur - 1, 1521 __x); 1522 --this->_M_impl._M_start._M_cur; 1523 } 1524 else 1525 _M_push_front_aux(__x); 1526 } 1527 1528 #if __cplusplus >= 201103L 1529 void 1530 push_front(value_type&& __x) 1531 { emplace_front(std::move(__x)); } 1532 1533 template<typename... _Args> 1534 #if __cplusplus > 201402L 1535 reference 1536 #else 1537 void 1538 #endif 1539 emplace_front(_Args&&... __args); 1540 #endif 1541 1542 /** 1543 * @brief Add data to the end of the %deque. 1544 * @param __x Data to be added. 1545 * 1546 * This is a typical stack operation. The function creates an 1547 * element at the end of the %deque and assigns the given data 1548 * to it. Due to the nature of a %deque this operation can be 1549 * done in constant time. 1550 */ 1551 void 1552 push_back(const value_type& __x) 1553 { 1554 if (this->_M_impl._M_finish._M_cur 1555 != this->_M_impl._M_finish._M_last - 1) 1556 { 1557 _Alloc_traits::construct(this->_M_impl, 1558 this->_M_impl._M_finish._M_cur, __x); 1559 ++this->_M_impl._M_finish._M_cur; 1560 } 1561 else 1562 _M_push_back_aux(__x); 1563 } 1564 1565 #if __cplusplus >= 201103L 1566 void 1567 push_back(value_type&& __x) 1568 { emplace_back(std::move(__x)); } 1569 1570 template<typename... _Args> 1571 #if __cplusplus > 201402L 1572 reference 1573 #else 1574 void 1575 #endif 1576 emplace_back(_Args&&... __args); 1577 #endif 1578 1579 /** 1580 * @brief Removes first element. 1581 * 1582 * This is a typical stack operation. It shrinks the %deque by one. 1583 * 1584 * Note that no data is returned, and if the first element's data is 1585 * needed, it should be retrieved before pop_front() is called. 1586 */ 1587 void 1588 pop_front() _GLIBCXX_NOEXCEPT 1589 { 1590 __glibcxx_requires_nonempty(); 1591 if (this->_M_impl._M_start._M_cur 1592 != this->_M_impl._M_start._M_last - 1) 1593 { 1594 _Alloc_traits::destroy(this->_M_impl, 1595 this->_M_impl._M_start._M_cur); 1596 ++this->_M_impl._M_start._M_cur; 1597 } 1598 else 1599 _M_pop_front_aux(); 1600 } 1601 1602 /** 1603 * @brief Removes last element. 1604 * 1605 * This is a typical stack operation. It shrinks the %deque by one. 1606 * 1607 * Note that no data is returned, and if the last element's data is 1608 * needed, it should be retrieved before pop_back() is called. 1609 */ 1610 void 1611 pop_back() _GLIBCXX_NOEXCEPT 1612 { 1613 __glibcxx_requires_nonempty(); 1614 if (this->_M_impl._M_finish._M_cur 1615 != this->_M_impl._M_finish._M_first) 1616 { 1617 --this->_M_impl._M_finish._M_cur; 1618 _Alloc_traits::destroy(this->_M_impl, 1619 this->_M_impl._M_finish._M_cur); 1620 } 1621 else 1622 _M_pop_back_aux(); 1623 } 1624 1625 #if __cplusplus >= 201103L 1626 /** 1627 * @brief Inserts an object in %deque before specified iterator. 1628 * @param __position A const_iterator into the %deque. 1629 * @param __args Arguments. 1630 * @return An iterator that points to the inserted data. 1631 * 1632 * This function will insert an object of type T constructed 1633 * with T(std::forward<Args>(args)...) before the specified location. 1634 */ 1635 template<typename... _Args> 1636 iterator 1637 emplace(const_iterator __position, _Args&&... __args); 1638 1639 /** 1640 * @brief Inserts given value into %deque before specified iterator. 1641 * @param __position A const_iterator into the %deque. 1642 * @param __x Data to be inserted. 1643 * @return An iterator that points to the inserted data. 1644 * 1645 * This function will insert a copy of the given value before the 1646 * specified location. 1647 */ 1648 iterator 1649 insert(const_iterator __position, const value_type& __x); 1650 #else 1651 /** 1652 * @brief Inserts given value into %deque before specified iterator. 1653 * @param __position An iterator into the %deque. 1654 * @param __x Data to be inserted. 1655 * @return An iterator that points to the inserted data. 1656 * 1657 * This function will insert a copy of the given value before the 1658 * specified location. 1659 */ 1660 iterator 1661 insert(iterator __position, const value_type& __x); 1662 #endif 1663 1664 #if __cplusplus >= 201103L 1665 /** 1666 * @brief Inserts given rvalue into %deque before specified iterator. 1667 * @param __position A const_iterator into the %deque. 1668 * @param __x Data to be inserted. 1669 * @return An iterator that points to the inserted data. 1670 * 1671 * This function will insert a copy of the given rvalue before the 1672 * specified location. 1673 */ 1674 iterator 1675 insert(const_iterator __position, value_type&& __x) 1676 { return emplace(__position, std::move(__x)); } 1677 1678 /** 1679 * @brief Inserts an initializer list into the %deque. 1680 * @param __p An iterator into the %deque. 1681 * @param __l An initializer_list. 1682 * 1683 * This function will insert copies of the data in the 1684 * initializer_list @a __l into the %deque before the location 1685 * specified by @a __p. This is known as <em>list insert</em>. 1686 */ 1687 iterator 1688 insert(const_iterator __p, initializer_list<value_type> __l) 1689 { 1690 auto __offset = __p - cbegin(); 1691 _M_range_insert_aux(__p._M_const_cast(), __l.begin(), __l.end(), 1692 std::random_access_iterator_tag()); 1693 return begin() + __offset; 1694 } 1695 #endif 1696 1697 #if __cplusplus >= 201103L 1698 /** 1699 * @brief Inserts a number of copies of given data into the %deque. 1700 * @param __position A const_iterator into the %deque. 1701 * @param __n Number of elements to be inserted. 1702 * @param __x Data to be inserted. 1703 * @return An iterator that points to the inserted data. 1704 * 1705 * This function will insert a specified number of copies of the given 1706 * data before the location specified by @a __position. 1707 */ 1708 iterator 1709 insert(const_iterator __position, size_type __n, const value_type& __x) 1710 { 1711 difference_type __offset = __position - cbegin(); 1712 _M_fill_insert(__position._M_const_cast(), __n, __x); 1713 return begin() + __offset; 1714 } 1715 #else 1716 /** 1717 * @brief Inserts a number of copies of given data into the %deque. 1718 * @param __position An iterator into the %deque. 1719 * @param __n Number of elements to be inserted. 1720 * @param __x Data to be inserted. 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 void 1726 insert(iterator __position, size_type __n, const value_type& __x) 1727 { _M_fill_insert(__position, __n, __x); } 1728 #endif 1729 1730 #if __cplusplus >= 201103L 1731 /** 1732 * @brief Inserts a range into the %deque. 1733 * @param __position A const_iterator into the %deque. 1734 * @param __first An input iterator. 1735 * @param __last An input iterator. 1736 * @return An iterator that points to the inserted data. 1737 * 1738 * This function will insert copies of the data in the range 1739 * [__first,__last) into the %deque before the location specified 1740 * by @a __position. This is known as <em>range insert</em>. 1741 */ 1742 template<typename _InputIterator, 1743 typename = std::_RequireInputIter<_InputIterator>> 1744 iterator 1745 insert(const_iterator __position, _InputIterator __first, 1746 _InputIterator __last) 1747 { 1748 difference_type __offset = __position - cbegin(); 1749 _M_insert_dispatch(__position._M_const_cast(), 1750 __first, __last, __false_type()); 1751 return begin() + __offset; 1752 } 1753 #else 1754 /** 1755 * @brief Inserts a range into the %deque. 1756 * @param __position An iterator into the %deque. 1757 * @param __first An input iterator. 1758 * @param __last An input iterator. 1759 * 1760 * This function will insert copies of the data in the range 1761 * [__first,__last) into the %deque before the location specified 1762 * by @a __position. This is known as <em>range insert</em>. 1763 */ 1764 template<typename _InputIterator> 1765 void 1766 insert(iterator __position, _InputIterator __first, 1767 _InputIterator __last) 1768 { 1769 // Check whether it's an integral type. If so, it's not an iterator. 1770 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1771 _M_insert_dispatch(__position, __first, __last, _Integral()); 1772 } 1773 #endif 1774 1775 /** 1776 * @brief Remove element at given position. 1777 * @param __position Iterator pointing to element to be erased. 1778 * @return An iterator pointing to the next element (or end()). 1779 * 1780 * This function will erase the element at the given position and thus 1781 * shorten the %deque by one. 1782 * 1783 * The user is cautioned that 1784 * this function only erases the element, and that if the element is 1785 * itself a pointer, the pointed-to memory is not touched in any way. 1786 * Managing the pointer is the user's responsibility. 1787 */ 1788 iterator 1789 #if __cplusplus >= 201103L 1790 erase(const_iterator __position) 1791 #else 1792 erase(iterator __position) 1793 #endif 1794 { return _M_erase(__position._M_const_cast()); } 1795 1796 /** 1797 * @brief Remove a range of elements. 1798 * @param __first Iterator pointing to the first element to be erased. 1799 * @param __last Iterator pointing to one past the last element to be 1800 * erased. 1801 * @return An iterator pointing to the element pointed to by @a last 1802 * prior to erasing (or end()). 1803 * 1804 * This function will erase the elements in the range 1805 * [__first,__last) and shorten the %deque accordingly. 1806 * 1807 * The user is cautioned that 1808 * this function only erases the elements, and that if the elements 1809 * themselves are pointers, the pointed-to memory is not touched in any 1810 * way. Managing the pointer is the user's responsibility. 1811 */ 1812 iterator 1813 #if __cplusplus >= 201103L 1814 erase(const_iterator __first, const_iterator __last) 1815 #else 1816 erase(iterator __first, iterator __last) 1817 #endif 1818 { return _M_erase(__first._M_const_cast(), __last._M_const_cast()); } 1819 1820 /** 1821 * @brief Swaps data with another %deque. 1822 * @param __x A %deque of the same element and allocator types. 1823 * 1824 * This exchanges the elements between two deques in constant time. 1825 * (Four pointers, so it should be quite fast.) 1826 * Note that the global std::swap() function is specialized such that 1827 * std::swap(d1,d2) will feed to this function. 1828 * 1829 * Whether the allocators are swapped depends on the allocator traits. 1830 */ 1831 void 1832 swap(deque& __x) _GLIBCXX_NOEXCEPT 1833 { 1834 #if __cplusplus >= 201103L 1835 __glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value 1836 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator()); 1837 #endif 1838 _M_impl._M_swap_data(__x._M_impl); 1839 _Alloc_traits::_S_on_swap(_M_get_Tp_allocator(), 1840 __x._M_get_Tp_allocator()); 1841 } 1842 1843 /** 1844 * Erases all the elements. Note that this function only erases the 1845 * elements, and that if the elements themselves are pointers, the 1846 * pointed-to memory is not touched in any way. Managing the pointer is 1847 * the user's responsibility. 1848 */ 1849 void 1850 clear() _GLIBCXX_NOEXCEPT 1851 { _M_erase_at_end(begin()); } 1852 1853 protected: 1854 // Internal constructor functions follow. 1855 1856 // called by the range constructor to implement [23.1.1]/9 1857 1858 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1859 // 438. Ambiguity in the "do the right thing" clause 1860 template<typename _Integer> 1861 void 1862 _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type) 1863 { 1864 _M_initialize_map(static_cast<size_type>(__n)); 1865 _M_fill_initialize(__x); 1866 } 1867 1868 // called by the range constructor to implement [23.1.1]/9 1869 template<typename _InputIterator> 1870 void 1871 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last, 1872 __false_type) 1873 { 1874 _M_range_initialize(__first, __last, 1875 std::__iterator_category(__first)); 1876 } 1877 1878 // called by the second initialize_dispatch above 1879 //@{ 1880 /** 1881 * @brief Fills the deque with whatever is in [first,last). 1882 * @param __first An input iterator. 1883 * @param __last An input iterator. 1884 * @return Nothing. 1885 * 1886 * If the iterators are actually forward iterators (or better), then the 1887 * memory layout can be done all at once. Else we move forward using 1888 * push_back on each value from the iterator. 1889 */ 1890 template<typename _InputIterator> 1891 void 1892 _M_range_initialize(_InputIterator __first, _InputIterator __last, 1893 std::input_iterator_tag); 1894 1895 // called by the second initialize_dispatch above 1896 template<typename _ForwardIterator> 1897 void 1898 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last, 1899 std::forward_iterator_tag); 1900 //@} 1901 1902 /** 1903 * @brief Fills the %deque with copies of value. 1904 * @param __value Initial value. 1905 * @return Nothing. 1906 * @pre _M_start and _M_finish have already been initialized, 1907 * but none of the %deque's elements have yet been constructed. 1908 * 1909 * This function is called only when the user provides an explicit size 1910 * (with or without an explicit exemplar value). 1911 */ 1912 void 1913 _M_fill_initialize(const value_type& __value); 1914 1915 #if __cplusplus >= 201103L 1916 // called by deque(n). 1917 void 1918 _M_default_initialize(); 1919 #endif 1920 1921 // Internal assign functions follow. The *_aux functions do the actual 1922 // assignment work for the range versions. 1923 1924 // called by the range assign to implement [23.1.1]/9 1925 1926 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1927 // 438. Ambiguity in the "do the right thing" clause 1928 template<typename _Integer> 1929 void 1930 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) 1931 { _M_fill_assign(__n, __val); } 1932 1933 // called by the range assign to implement [23.1.1]/9 1934 template<typename _InputIterator> 1935 void 1936 _M_assign_dispatch(_InputIterator __first, _InputIterator __last, 1937 __false_type) 1938 { _M_assign_aux(__first, __last, std::__iterator_category(__first)); } 1939 1940 // called by the second assign_dispatch above 1941 template<typename _InputIterator> 1942 void 1943 _M_assign_aux(_InputIterator __first, _InputIterator __last, 1944 std::input_iterator_tag); 1945 1946 // called by the second assign_dispatch above 1947 template<typename _ForwardIterator> 1948 void 1949 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last, 1950 std::forward_iterator_tag) 1951 { 1952 const size_type __len = std::distance(__first, __last); 1953 if (__len > size()) 1954 { 1955 _ForwardIterator __mid = __first; 1956 std::advance(__mid, size()); 1957 std::copy(__first, __mid, begin()); 1958 _M_range_insert_aux(end(), __mid, __last, 1959 std::__iterator_category(__first)); 1960 } 1961 else 1962 _M_erase_at_end(std::copy(__first, __last, begin())); 1963 } 1964 1965 // Called by assign(n,t), and the range assign when it turns out 1966 // to be the same thing. 1967 void 1968 _M_fill_assign(size_type __n, const value_type& __val) 1969 { 1970 if (__n > size()) 1971 { 1972 std::fill(begin(), end(), __val); 1973 _M_fill_insert(end(), __n - size(), __val); 1974 } 1975 else 1976 { 1977 _M_erase_at_end(begin() + difference_type(__n)); 1978 std::fill(begin(), end(), __val); 1979 } 1980 } 1981 1982 //@{ 1983 /// Helper functions for push_* and pop_*. 1984 #if __cplusplus < 201103L 1985 void _M_push_back_aux(const value_type&); 1986 1987 void _M_push_front_aux(const value_type&); 1988 #else 1989 template<typename... _Args> 1990 void _M_push_back_aux(_Args&&... __args); 1991 1992 template<typename... _Args> 1993 void _M_push_front_aux(_Args&&... __args); 1994 #endif 1995 1996 void _M_pop_back_aux(); 1997 1998 void _M_pop_front_aux(); 1999 //@} 2000 2001 // Internal insert functions follow. The *_aux functions do the actual 2002 // insertion work when all shortcuts fail. 2003 2004 // called by the range insert to implement [23.1.1]/9 2005 2006 // _GLIBCXX_RESOLVE_LIB_DEFECTS 2007 // 438. Ambiguity in the "do the right thing" clause 2008 template<typename _Integer> 2009 void 2010 _M_insert_dispatch(iterator __pos, 2011 _Integer __n, _Integer __x, __true_type) 2012 { _M_fill_insert(__pos, __n, __x); } 2013 2014 // called by the range insert to implement [23.1.1]/9 2015 template<typename _InputIterator> 2016 void 2017 _M_insert_dispatch(iterator __pos, 2018 _InputIterator __first, _InputIterator __last, 2019 __false_type) 2020 { 2021 _M_range_insert_aux(__pos, __first, __last, 2022 std::__iterator_category(__first)); 2023 } 2024 2025 // called by the second insert_dispatch above 2026 template<typename _InputIterator> 2027 void 2028 _M_range_insert_aux(iterator __pos, _InputIterator __first, 2029 _InputIterator __last, std::input_iterator_tag); 2030 2031 // called by the second insert_dispatch above 2032 template<typename _ForwardIterator> 2033 void 2034 _M_range_insert_aux(iterator __pos, _ForwardIterator __first, 2035 _ForwardIterator __last, std::forward_iterator_tag); 2036 2037 // Called by insert(p,n,x), and the range insert when it turns out to be 2038 // the same thing. Can use fill functions in optimal situations, 2039 // otherwise passes off to insert_aux(p,n,x). 2040 void 2041 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x); 2042 2043 // called by insert(p,x) 2044 #if __cplusplus < 201103L 2045 iterator 2046 _M_insert_aux(iterator __pos, const value_type& __x); 2047 #else 2048 template<typename... _Args> 2049 iterator 2050 _M_insert_aux(iterator __pos, _Args&&... __args); 2051 #endif 2052 2053 // called by insert(p,n,x) via fill_insert 2054 void 2055 _M_insert_aux(iterator __pos, size_type __n, const value_type& __x); 2056 2057 // called by range_insert_aux for forward iterators 2058 template<typename _ForwardIterator> 2059 void 2060 _M_insert_aux(iterator __pos, 2061 _ForwardIterator __first, _ForwardIterator __last, 2062 size_type __n); 2063 2064 2065 // Internal erase functions follow. 2066 2067 void 2068 _M_destroy_data_aux(iterator __first, iterator __last); 2069 2070 // Called by ~deque(). 2071 // NB: Doesn't deallocate the nodes. 2072 template<typename _Alloc1> 2073 void 2074 _M_destroy_data(iterator __first, iterator __last, const _Alloc1&) 2075 { _M_destroy_data_aux(__first, __last); } 2076 2077 void 2078 _M_destroy_data(iterator __first, iterator __last, 2079 const std::allocator<_Tp>&) 2080 { 2081 if (!__has_trivial_destructor(value_type)) 2082 _M_destroy_data_aux(__first, __last); 2083 } 2084 2085 // Called by erase(q1, q2). 2086 void 2087 _M_erase_at_begin(iterator __pos) 2088 { 2089 _M_destroy_data(begin(), __pos, _M_get_Tp_allocator()); 2090 _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node); 2091 this->_M_impl._M_start = __pos; 2092 } 2093 2094 // Called by erase(q1, q2), resize(), clear(), _M_assign_aux, 2095 // _M_fill_assign, operator=. 2096 void 2097 _M_erase_at_end(iterator __pos) 2098 { 2099 _M_destroy_data(__pos, end(), _M_get_Tp_allocator()); 2100 _M_destroy_nodes(__pos._M_node + 1, 2101 this->_M_impl._M_finish._M_node + 1); 2102 this->_M_impl._M_finish = __pos; 2103 } 2104 2105 iterator 2106 _M_erase(iterator __pos); 2107 2108 iterator 2109 _M_erase(iterator __first, iterator __last); 2110 2111 #if __cplusplus >= 201103L 2112 // Called by resize(sz). 2113 void 2114 _M_default_append(size_type __n); 2115 2116 bool 2117 _M_shrink_to_fit(); 2118 #endif 2119 2120 //@{ 2121 /// Memory-handling helpers for the previous internal insert functions. 2122 iterator 2123 _M_reserve_elements_at_front(size_type __n) 2124 { 2125 const size_type __vacancies = this->_M_impl._M_start._M_cur 2126 - this->_M_impl._M_start._M_first; 2127 if (__n > __vacancies) 2128 _M_new_elements_at_front(__n - __vacancies); 2129 return this->_M_impl._M_start - difference_type(__n); 2130 } 2131 2132 iterator 2133 _M_reserve_elements_at_back(size_type __n) 2134 { 2135 const size_type __vacancies = (this->_M_impl._M_finish._M_last 2136 - this->_M_impl._M_finish._M_cur) - 1; 2137 if (__n > __vacancies) 2138 _M_new_elements_at_back(__n - __vacancies); 2139 return this->_M_impl._M_finish + difference_type(__n); 2140 } 2141 2142 void 2143 _M_new_elements_at_front(size_type __new_elements); 2144 2145 void 2146 _M_new_elements_at_back(size_type __new_elements); 2147 //@} 2148 2149 2150 //@{ 2151 /** 2152 * @brief Memory-handling helpers for the major %map. 2153 * 2154 * Makes sure the _M_map has space for new nodes. Does not 2155 * actually add the nodes. Can invalidate _M_map pointers. 2156 * (And consequently, %deque iterators.) 2157 */ 2158 void 2159 _M_reserve_map_at_back(size_type __nodes_to_add = 1) 2160 { 2161 if (__nodes_to_add + 1 > this->_M_impl._M_map_size 2162 - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map)) 2163 _M_reallocate_map(__nodes_to_add, false); 2164 } 2165 2166 void 2167 _M_reserve_map_at_front(size_type __nodes_to_add = 1) 2168 { 2169 if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node 2170 - this->_M_impl._M_map)) 2171 _M_reallocate_map(__nodes_to_add, true); 2172 } 2173 2174 void 2175 _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front); 2176 //@} 2177 2178 #if __cplusplus >= 201103L 2179 // Constant-time, nothrow move assignment when source object's memory 2180 // can be moved because the allocators are equal. 2181 void 2182 _M_move_assign1(deque&& __x, /* always equal: */ true_type) noexcept 2183 { 2184 this->_M_impl._M_swap_data(__x._M_impl); 2185 __x.clear(); 2186 std::__alloc_on_move(_M_get_Tp_allocator(), __x._M_get_Tp_allocator()); 2187 } 2188 2189 // When the allocators are not equal the operation could throw, because 2190 // we might need to allocate a new map for __x after moving from it 2191 // or we might need to allocate new elements for *this. 2192 void 2193 _M_move_assign1(deque&& __x, /* always equal: */ false_type) 2194 { 2195 constexpr bool __move_storage = 2196 _Alloc_traits::_S_propagate_on_move_assign(); 2197 _M_move_assign2(std::move(__x), __bool_constant<__move_storage>()); 2198 } 2199 2200 // Destroy all elements and deallocate all memory, then replace 2201 // with elements created from __args. 2202 template<typename... _Args> 2203 void 2204 _M_replace_map(_Args&&... __args) 2205 { 2206 // Create new data first, so if allocation fails there are no effects. 2207 deque __newobj(std::forward<_Args>(__args)...); 2208 // Free existing storage using existing allocator. 2209 clear(); 2210 _M_deallocate_node(*begin()._M_node); // one node left after clear() 2211 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 2212 this->_M_impl._M_map = nullptr; 2213 this->_M_impl._M_map_size = 0; 2214 // Take ownership of replacement memory. 2215 this->_M_impl._M_swap_data(__newobj._M_impl); 2216 } 2217 2218 // Do move assignment when the allocator propagates. 2219 void 2220 _M_move_assign2(deque&& __x, /* propagate: */ true_type) 2221 { 2222 // Make a copy of the original allocator state. 2223 auto __alloc = __x._M_get_Tp_allocator(); 2224 // The allocator propagates so storage can be moved from __x, 2225 // leaving __x in a valid empty state with a moved-from allocator. 2226 _M_replace_map(std::move(__x)); 2227 // Move the corresponding allocator state too. 2228 _M_get_Tp_allocator() = std::move(__alloc); 2229 } 2230 2231 // Do move assignment when it may not be possible to move source 2232 // object's memory, resulting in a linear-time operation. 2233 void 2234 _M_move_assign2(deque&& __x, /* propagate: */ false_type) 2235 { 2236 if (__x._M_get_Tp_allocator() == this->_M_get_Tp_allocator()) 2237 { 2238 // The allocators are equal so storage can be moved from __x, 2239 // leaving __x in a valid empty state with its current allocator. 2240 _M_replace_map(std::move(__x), __x.get_allocator()); 2241 } 2242 else 2243 { 2244 // The rvalue's allocator cannot be moved and is not equal, 2245 // so we need to individually move each element. 2246 _M_assign_aux(std::__make_move_if_noexcept_iterator(__x.begin()), 2247 std::__make_move_if_noexcept_iterator(__x.end()), 2248 std::random_access_iterator_tag()); 2249 __x.clear(); 2250 } 2251 } 2252 #endif 2253 }; 2254 2255 #if __cpp_deduction_guides >= 201606 2256 template<typename _InputIterator, typename _ValT 2257 = typename iterator_traits<_InputIterator>::value_type, 2258 typename _Allocator = allocator<_ValT>, 2259 typename = _RequireInputIter<_InputIterator>, 2260 typename = _RequireAllocator<_Allocator>> 2261 deque(_InputIterator, _InputIterator, _Allocator = _Allocator()) 2262 -> deque<_ValT, _Allocator>; 2263 #endif 2264 2265 /** 2266 * @brief Deque equality comparison. 2267 * @param __x A %deque. 2268 * @param __y A %deque of the same type as @a __x. 2269 * @return True iff the size and elements of the deques are equal. 2270 * 2271 * This is an equivalence relation. It is linear in the size of the 2272 * deques. Deques are considered equivalent if their sizes are equal, 2273 * and if corresponding elements compare equal. 2274 */ 2275 template<typename _Tp, typename _Alloc> 2276 inline bool 2277 operator==(const deque<_Tp, _Alloc>& __x, 2278 const deque<_Tp, _Alloc>& __y) 2279 { return __x.size() == __y.size() 2280 && std::equal(__x.begin(), __x.end(), __y.begin()); } 2281 2282 /** 2283 * @brief Deque ordering relation. 2284 * @param __x A %deque. 2285 * @param __y A %deque of the same type as @a __x. 2286 * @return True iff @a x is lexicographically less than @a __y. 2287 * 2288 * This is a total ordering relation. It is linear in the size of the 2289 * deques. The elements must be comparable with @c <. 2290 * 2291 * See std::lexicographical_compare() for how the determination is made. 2292 */ 2293 template<typename _Tp, typename _Alloc> 2294 inline bool 2295 operator<(const deque<_Tp, _Alloc>& __x, 2296 const deque<_Tp, _Alloc>& __y) 2297 { return std::lexicographical_compare(__x.begin(), __x.end(), 2298 __y.begin(), __y.end()); } 2299 2300 /// Based on operator== 2301 template<typename _Tp, typename _Alloc> 2302 inline bool 2303 operator!=(const deque<_Tp, _Alloc>& __x, 2304 const deque<_Tp, _Alloc>& __y) 2305 { return !(__x == __y); } 2306 2307 /// Based on operator< 2308 template<typename _Tp, typename _Alloc> 2309 inline bool 2310 operator>(const deque<_Tp, _Alloc>& __x, 2311 const deque<_Tp, _Alloc>& __y) 2312 { return __y < __x; } 2313 2314 /// Based on operator< 2315 template<typename _Tp, typename _Alloc> 2316 inline bool 2317 operator<=(const deque<_Tp, _Alloc>& __x, 2318 const deque<_Tp, _Alloc>& __y) 2319 { return !(__y < __x); } 2320 2321 /// Based on operator< 2322 template<typename _Tp, typename _Alloc> 2323 inline bool 2324 operator>=(const deque<_Tp, _Alloc>& __x, 2325 const deque<_Tp, _Alloc>& __y) 2326 { return !(__x < __y); } 2327 2328 /// See std::deque::swap(). 2329 template<typename _Tp, typename _Alloc> 2330 inline void 2331 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y) 2332 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y))) 2333 { __x.swap(__y); } 2334 2335 #undef _GLIBCXX_DEQUE_BUF_SIZE 2336 2337 _GLIBCXX_END_NAMESPACE_CONTAINER 2338 _GLIBCXX_END_NAMESPACE_VERSION 2339 } // namespace std 2340 2341 #endif /* _STL_DEQUE_H */ 2342