1 // Deque implementation -*- C++ -*- 2 3 // Copyright (C) 2001-2017 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_CONTAINER 71 72 /** 73 * @brief This function controls the size of memory nodes. 74 * @param __size The size of an element. 75 * @return The number (not byte size) of elements per node. 76 * 77 * This function started off as a compiler kludge from SGI, but 78 * seems to be a useful wrapper around a repeated constant 79 * expression. The @b 512 is tunable (and no other code needs to 80 * change), but no investigation has been done since inheriting the 81 * SGI code. Touch _GLIBCXX_DEQUE_BUF_SIZE only if you know what 82 * you are doing, however: changing it breaks the binary 83 * compatibility!! 84 */ 85 86 #ifndef _GLIBCXX_DEQUE_BUF_SIZE 87 #define _GLIBCXX_DEQUE_BUF_SIZE 512 88 #endif 89 90 _GLIBCXX_CONSTEXPR inline size_t 91 __deque_buf_size(size_t __size) 92 { return (__size < _GLIBCXX_DEQUE_BUF_SIZE 93 ? size_t(_GLIBCXX_DEQUE_BUF_SIZE / __size) : size_t(1)); } 94 95 96 /** 97 * @brief A deque::iterator. 98 * 99 * Quite a bit of intelligence here. Much of the functionality of 100 * deque is actually passed off to this class. A deque holds two 101 * of these internally, marking its valid range. Access to 102 * elements is done as offsets of either of those two, relying on 103 * operator overloading in this class. 104 * 105 * All the functions are op overloads except for _M_set_node. 106 */ 107 template<typename _Tp, typename _Ref, typename _Ptr> 108 struct _Deque_iterator 109 { 110 #if __cplusplus < 201103L 111 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator; 112 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator; 113 typedef _Tp* _Elt_pointer; 114 typedef _Tp** _Map_pointer; 115 #else 116 private: 117 template<typename _Up> 118 using __ptr_to = typename pointer_traits<_Ptr>::template rebind<_Up>; 119 template<typename _CvTp> 120 using __iter = _Deque_iterator<_Tp, _CvTp&, __ptr_to<_CvTp>>; 121 public: 122 typedef __iter<_Tp> iterator; 123 typedef __iter<const _Tp> const_iterator; 124 typedef __ptr_to<_Tp> _Elt_pointer; 125 typedef __ptr_to<_Elt_pointer> _Map_pointer; 126 #endif 127 128 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 129 { return __deque_buf_size(sizeof(_Tp)); } 130 131 typedef std::random_access_iterator_tag iterator_category; 132 typedef _Tp value_type; 133 typedef _Ptr pointer; 134 typedef _Ref reference; 135 typedef size_t size_type; 136 typedef ptrdiff_t difference_type; 137 typedef _Deque_iterator _Self; 138 139 _Elt_pointer _M_cur; 140 _Elt_pointer _M_first; 141 _Elt_pointer _M_last; 142 _Map_pointer _M_node; 143 144 _Deque_iterator(_Elt_pointer __x, _Map_pointer __y) _GLIBCXX_NOEXCEPT 145 : _M_cur(__x), _M_first(*__y), 146 _M_last(*__y + _S_buffer_size()), _M_node(__y) { } 147 148 _Deque_iterator() _GLIBCXX_NOEXCEPT 149 : _M_cur(), _M_first(), _M_last(), _M_node() { } 150 151 _Deque_iterator(const iterator& __x) _GLIBCXX_NOEXCEPT 152 : _M_cur(__x._M_cur), _M_first(__x._M_first), 153 _M_last(__x._M_last), _M_node(__x._M_node) { } 154 155 iterator 156 _M_const_cast() const _GLIBCXX_NOEXCEPT 157 { return iterator(_M_cur, _M_node); } 158 159 reference 160 operator*() const _GLIBCXX_NOEXCEPT 161 { return *_M_cur; } 162 163 pointer 164 operator->() const _GLIBCXX_NOEXCEPT 165 { return _M_cur; } 166 167 _Self& 168 operator++() _GLIBCXX_NOEXCEPT 169 { 170 ++_M_cur; 171 if (_M_cur == _M_last) 172 { 173 _M_set_node(_M_node + 1); 174 _M_cur = _M_first; 175 } 176 return *this; 177 } 178 179 _Self 180 operator++(int) _GLIBCXX_NOEXCEPT 181 { 182 _Self __tmp = *this; 183 ++*this; 184 return __tmp; 185 } 186 187 _Self& 188 operator--() _GLIBCXX_NOEXCEPT 189 { 190 if (_M_cur == _M_first) 191 { 192 _M_set_node(_M_node - 1); 193 _M_cur = _M_last; 194 } 195 --_M_cur; 196 return *this; 197 } 198 199 _Self 200 operator--(int) _GLIBCXX_NOEXCEPT 201 { 202 _Self __tmp = *this; 203 --*this; 204 return __tmp; 205 } 206 207 _Self& 208 operator+=(difference_type __n) _GLIBCXX_NOEXCEPT 209 { 210 const difference_type __offset = __n + (_M_cur - _M_first); 211 if (__offset >= 0 && __offset < difference_type(_S_buffer_size())) 212 _M_cur += __n; 213 else 214 { 215 const difference_type __node_offset = 216 __offset > 0 ? __offset / difference_type(_S_buffer_size()) 217 : -difference_type((-__offset - 1) 218 / _S_buffer_size()) - 1; 219 _M_set_node(_M_node + __node_offset); 220 _M_cur = _M_first + (__offset - __node_offset 221 * difference_type(_S_buffer_size())); 222 } 223 return *this; 224 } 225 226 _Self 227 operator+(difference_type __n) const _GLIBCXX_NOEXCEPT 228 { 229 _Self __tmp = *this; 230 return __tmp += __n; 231 } 232 233 _Self& 234 operator-=(difference_type __n) _GLIBCXX_NOEXCEPT 235 { return *this += -__n; } 236 237 _Self 238 operator-(difference_type __n) const _GLIBCXX_NOEXCEPT 239 { 240 _Self __tmp = *this; 241 return __tmp -= __n; 242 } 243 244 reference 245 operator[](difference_type __n) const _GLIBCXX_NOEXCEPT 246 { return *(*this + __n); } 247 248 /** 249 * Prepares to traverse new_node. Sets everything except 250 * _M_cur, which should therefore be set by the caller 251 * immediately afterwards, based on _M_first and _M_last. 252 */ 253 void 254 _M_set_node(_Map_pointer __new_node) _GLIBCXX_NOEXCEPT 255 { 256 _M_node = __new_node; 257 _M_first = *__new_node; 258 _M_last = _M_first + difference_type(_S_buffer_size()); 259 } 260 }; 261 262 // Note: we also provide overloads whose operands are of the same type in 263 // order to avoid ambiguous overload resolution when std::rel_ops operators 264 // are in scope (for additional details, see libstdc++/3628) 265 template<typename _Tp, typename _Ref, typename _Ptr> 266 inline bool 267 operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 268 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 269 { return __x._M_cur == __y._M_cur; } 270 271 template<typename _Tp, typename _RefL, typename _PtrL, 272 typename _RefR, typename _PtrR> 273 inline bool 274 operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 275 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 276 { return __x._M_cur == __y._M_cur; } 277 278 template<typename _Tp, typename _Ref, typename _Ptr> 279 inline bool 280 operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 281 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 282 { return !(__x == __y); } 283 284 template<typename _Tp, typename _RefL, typename _PtrL, 285 typename _RefR, typename _PtrR> 286 inline bool 287 operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 288 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 289 { return !(__x == __y); } 290 291 template<typename _Tp, typename _Ref, typename _Ptr> 292 inline bool 293 operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 294 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 295 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 296 : (__x._M_node < __y._M_node); } 297 298 template<typename _Tp, typename _RefL, typename _PtrL, 299 typename _RefR, typename _PtrR> 300 inline bool 301 operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 302 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 303 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 304 : (__x._M_node < __y._M_node); } 305 306 template<typename _Tp, typename _Ref, typename _Ptr> 307 inline bool 308 operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 309 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 310 { return __y < __x; } 311 312 template<typename _Tp, typename _RefL, typename _PtrL, 313 typename _RefR, typename _PtrR> 314 inline bool 315 operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 316 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 317 { return __y < __x; } 318 319 template<typename _Tp, typename _Ref, typename _Ptr> 320 inline bool 321 operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 322 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 323 { return !(__y < __x); } 324 325 template<typename _Tp, typename _RefL, typename _PtrL, 326 typename _RefR, typename _PtrR> 327 inline bool 328 operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 329 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 330 { return !(__y < __x); } 331 332 template<typename _Tp, typename _Ref, typename _Ptr> 333 inline bool 334 operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 335 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 336 { return !(__x < __y); } 337 338 template<typename _Tp, typename _RefL, typename _PtrL, 339 typename _RefR, typename _PtrR> 340 inline bool 341 operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 342 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 343 { return !(__x < __y); } 344 345 // _GLIBCXX_RESOLVE_LIB_DEFECTS 346 // According to the resolution of DR179 not only the various comparison 347 // operators but also operator- must accept mixed iterator/const_iterator 348 // parameters. 349 template<typename _Tp, typename _Ref, typename _Ptr> 350 inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 351 operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 352 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) _GLIBCXX_NOEXCEPT 353 { 354 return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 355 (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size()) 356 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 357 + (__y._M_last - __y._M_cur); 358 } 359 360 template<typename _Tp, typename _RefL, typename _PtrL, 361 typename _RefR, typename _PtrR> 362 inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 363 operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 364 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) _GLIBCXX_NOEXCEPT 365 { 366 return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 367 (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size()) 368 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 369 + (__y._M_last - __y._M_cur); 370 } 371 372 template<typename _Tp, typename _Ref, typename _Ptr> 373 inline _Deque_iterator<_Tp, _Ref, _Ptr> 374 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x) 375 _GLIBCXX_NOEXCEPT 376 { return __x + __n; } 377 378 template<typename _Tp> 379 void 380 fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>&, 381 const _Deque_iterator<_Tp, _Tp&, _Tp*>&, const _Tp&); 382 383 template<typename _Tp> 384 _Deque_iterator<_Tp, _Tp&, _Tp*> 385 copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 386 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 387 _Deque_iterator<_Tp, _Tp&, _Tp*>); 388 389 template<typename _Tp> 390 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 391 copy(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 392 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 393 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 394 { return std::copy(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 395 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 396 __result); } 397 398 template<typename _Tp> 399 _Deque_iterator<_Tp, _Tp&, _Tp*> 400 copy_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 401 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 402 _Deque_iterator<_Tp, _Tp&, _Tp*>); 403 404 template<typename _Tp> 405 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 406 copy_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 407 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 408 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 409 { return std::copy_backward(_Deque_iterator<_Tp, 410 const _Tp&, const _Tp*>(__first), 411 _Deque_iterator<_Tp, 412 const _Tp&, const _Tp*>(__last), 413 __result); } 414 415 #if __cplusplus >= 201103L 416 template<typename _Tp> 417 _Deque_iterator<_Tp, _Tp&, _Tp*> 418 move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 419 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 420 _Deque_iterator<_Tp, _Tp&, _Tp*>); 421 422 template<typename _Tp> 423 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 424 move(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 425 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 426 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 427 { return std::move(_Deque_iterator<_Tp, const _Tp&, const _Tp*>(__first), 428 _Deque_iterator<_Tp, const _Tp&, const _Tp*>(__last), 429 __result); } 430 431 template<typename _Tp> 432 _Deque_iterator<_Tp, _Tp&, _Tp*> 433 move_backward(_Deque_iterator<_Tp, const _Tp&, const _Tp*>, 434 _Deque_iterator<_Tp, const _Tp&, const _Tp*>, 435 _Deque_iterator<_Tp, _Tp&, _Tp*>); 436 437 template<typename _Tp> 438 inline _Deque_iterator<_Tp, _Tp&, _Tp*> 439 move_backward(_Deque_iterator<_Tp, _Tp&, _Tp*> __first, 440 _Deque_iterator<_Tp, _Tp&, _Tp*> __last, 441 _Deque_iterator<_Tp, _Tp&, _Tp*> __result) 442 { return std::move_backward(_Deque_iterator<_Tp, 443 const _Tp&, const _Tp*>(__first), 444 _Deque_iterator<_Tp, 445 const _Tp&, const _Tp*>(__last), 446 __result); } 447 #endif 448 449 /** 450 * Deque base class. This class provides the unified face for %deque's 451 * allocation. This class's constructor and destructor allocate and 452 * deallocate (but do not initialize) storage. This makes %exception 453 * safety easier. 454 * 455 * Nothing in this class ever constructs or destroys an actual Tp element. 456 * (Deque handles that itself.) Only/All memory management is performed 457 * here. 458 */ 459 template<typename _Tp, typename _Alloc> 460 class _Deque_base 461 { 462 protected: 463 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template 464 rebind<_Tp>::other _Tp_alloc_type; 465 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits; 466 467 #if __cplusplus < 201103L 468 typedef _Tp* _Ptr; 469 typedef const _Tp* _Ptr_const; 470 #else 471 typedef typename _Alloc_traits::pointer _Ptr; 472 typedef typename _Alloc_traits::const_pointer _Ptr_const; 473 #endif 474 475 typedef typename _Alloc_traits::template rebind<_Ptr>::other 476 _Map_alloc_type; 477 typedef __gnu_cxx::__alloc_traits<_Map_alloc_type> _Map_alloc_traits; 478 479 public: 480 typedef _Alloc allocator_type; 481 typedef typename _Alloc_traits::size_type size_type; 482 483 allocator_type 484 get_allocator() const _GLIBCXX_NOEXCEPT 485 { return allocator_type(_M_get_Tp_allocator()); } 486 487 typedef _Deque_iterator<_Tp, _Tp&, _Ptr> iterator; 488 typedef _Deque_iterator<_Tp, const _Tp&, _Ptr_const> const_iterator; 489 490 _Deque_base() 491 : _M_impl() 492 { _M_initialize_map(0); } 493 494 _Deque_base(size_t __num_elements) 495 : _M_impl() 496 { _M_initialize_map(__num_elements); } 497 498 _Deque_base(const allocator_type& __a, size_t __num_elements) 499 : _M_impl(__a) 500 { _M_initialize_map(__num_elements); } 501 502 _Deque_base(const allocator_type& __a) 503 : _M_impl(__a) 504 { /* Caller must initialize map. */ } 505 506 #if __cplusplus >= 201103L 507 _Deque_base(_Deque_base&& __x, false_type) 508 : _M_impl(__x._M_move_impl()) 509 { } 510 511 _Deque_base(_Deque_base&& __x, true_type) 512 : _M_impl(std::move(__x._M_get_Tp_allocator())) 513 { 514 _M_initialize_map(0); 515 if (__x._M_impl._M_map) 516 this->_M_impl._M_swap_data(__x._M_impl); 517 } 518 519 _Deque_base(_Deque_base&& __x) 520 : _Deque_base(std::move(__x), typename _Alloc_traits::is_always_equal{}) 521 { } 522 523 _Deque_base(_Deque_base&& __x, const allocator_type& __a, size_type __n) 524 : _M_impl(__a) 525 { 526 if (__x.get_allocator() == __a) 527 { 528 if (__x._M_impl._M_map) 529 { 530 _M_initialize_map(0); 531 this->_M_impl._M_swap_data(__x._M_impl); 532 } 533 } 534 else 535 { 536 _M_initialize_map(__n); 537 } 538 } 539 #endif 540 541 ~_Deque_base() _GLIBCXX_NOEXCEPT; 542 543 protected: 544 typedef typename iterator::_Map_pointer _Map_pointer; 545 546 //This struct encapsulates the implementation of the std::deque 547 //standard container and at the same time makes use of the EBO 548 //for empty allocators. 549 struct _Deque_impl 550 : public _Tp_alloc_type 551 { 552 _Map_pointer _M_map; 553 size_t _M_map_size; 554 iterator _M_start; 555 iterator _M_finish; 556 557 _Deque_impl() 558 : _Tp_alloc_type(), _M_map(), _M_map_size(0), 559 _M_start(), _M_finish() 560 { } 561 562 _Deque_impl(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT 563 : _Tp_alloc_type(__a), _M_map(), _M_map_size(0), 564 _M_start(), _M_finish() 565 { } 566 567 #if __cplusplus >= 201103L 568 _Deque_impl(_Deque_impl&&) = default; 569 570 _Deque_impl(_Tp_alloc_type&& __a) noexcept 571 : _Tp_alloc_type(std::move(__a)), _M_map(), _M_map_size(0), 572 _M_start(), _M_finish() 573 { } 574 #endif 575 576 void _M_swap_data(_Deque_impl& __x) _GLIBCXX_NOEXCEPT 577 { 578 using std::swap; 579 swap(this->_M_start, __x._M_start); 580 swap(this->_M_finish, __x._M_finish); 581 swap(this->_M_map, __x._M_map); 582 swap(this->_M_map_size, __x._M_map_size); 583 } 584 }; 585 586 _Tp_alloc_type& 587 _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT 588 { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); } 589 590 const _Tp_alloc_type& 591 _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT 592 { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); } 593 594 _Map_alloc_type 595 _M_get_map_allocator() const _GLIBCXX_NOEXCEPT 596 { return _Map_alloc_type(_M_get_Tp_allocator()); } 597 598 _Ptr 599 _M_allocate_node() 600 { 601 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 602 return _Traits::allocate(_M_impl, __deque_buf_size(sizeof(_Tp))); 603 } 604 605 void 606 _M_deallocate_node(_Ptr __p) _GLIBCXX_NOEXCEPT 607 { 608 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Traits; 609 _Traits::deallocate(_M_impl, __p, __deque_buf_size(sizeof(_Tp))); 610 } 611 612 _Map_pointer 613 _M_allocate_map(size_t __n) 614 { 615 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 616 return _Map_alloc_traits::allocate(__map_alloc, __n); 617 } 618 619 void 620 _M_deallocate_map(_Map_pointer __p, size_t __n) _GLIBCXX_NOEXCEPT 621 { 622 _Map_alloc_type __map_alloc = _M_get_map_allocator(); 623 _Map_alloc_traits::deallocate(__map_alloc, __p, __n); 624 } 625 626 protected: 627 void _M_initialize_map(size_t); 628 void _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish); 629 void _M_destroy_nodes(_Map_pointer __nstart, 630 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT; 631 enum { _S_initial_map_size = 8 }; 632 633 _Deque_impl _M_impl; 634 635 #if __cplusplus >= 201103L 636 private: 637 _Deque_impl 638 _M_move_impl() 639 { 640 if (!_M_impl._M_map) 641 return std::move(_M_impl); 642 643 // Create a copy of the current allocator. 644 _Tp_alloc_type __alloc{_M_get_Tp_allocator()}; 645 // Put that copy in a moved-from state. 646 _Tp_alloc_type __sink __attribute((__unused__)) {std::move(__alloc)}; 647 // Create an empty map that allocates using the moved-from allocator. 648 _Deque_base __empty{__alloc}; 649 __empty._M_initialize_map(0); 650 // Now safe to modify current allocator and perform non-throwing swaps. 651 _Deque_impl __ret{std::move(_M_get_Tp_allocator())}; 652 _M_impl._M_swap_data(__ret); 653 _M_impl._M_swap_data(__empty._M_impl); 654 return __ret; 655 } 656 #endif 657 }; 658 659 template<typename _Tp, typename _Alloc> 660 _Deque_base<_Tp, _Alloc>:: 661 ~_Deque_base() _GLIBCXX_NOEXCEPT 662 { 663 if (this->_M_impl._M_map) 664 { 665 _M_destroy_nodes(this->_M_impl._M_start._M_node, 666 this->_M_impl._M_finish._M_node + 1); 667 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 668 } 669 } 670 671 /** 672 * @brief Layout storage. 673 * @param __num_elements The count of T's for which to allocate space 674 * at first. 675 * @return Nothing. 676 * 677 * The initial underlying memory layout is a bit complicated... 678 */ 679 template<typename _Tp, typename _Alloc> 680 void 681 _Deque_base<_Tp, _Alloc>:: 682 _M_initialize_map(size_t __num_elements) 683 { 684 const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp)) 685 + 1); 686 687 this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size, 688 size_t(__num_nodes + 2)); 689 this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size); 690 691 // For "small" maps (needing less than _M_map_size nodes), allocation 692 // starts in the middle elements and grows outwards. So nstart may be 693 // the beginning of _M_map, but for small maps it may be as far in as 694 // _M_map+3. 695 696 _Map_pointer __nstart = (this->_M_impl._M_map 697 + (this->_M_impl._M_map_size - __num_nodes) / 2); 698 _Map_pointer __nfinish = __nstart + __num_nodes; 699 700 __try 701 { _M_create_nodes(__nstart, __nfinish); } 702 __catch(...) 703 { 704 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 705 this->_M_impl._M_map = _Map_pointer(); 706 this->_M_impl._M_map_size = 0; 707 __throw_exception_again; 708 } 709 710 this->_M_impl._M_start._M_set_node(__nstart); 711 this->_M_impl._M_finish._M_set_node(__nfinish - 1); 712 this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first; 713 this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first 714 + __num_elements 715 % __deque_buf_size(sizeof(_Tp))); 716 } 717 718 template<typename _Tp, typename _Alloc> 719 void 720 _Deque_base<_Tp, _Alloc>:: 721 _M_create_nodes(_Map_pointer __nstart, _Map_pointer __nfinish) 722 { 723 _Map_pointer __cur; 724 __try 725 { 726 for (__cur = __nstart; __cur < __nfinish; ++__cur) 727 *__cur = this->_M_allocate_node(); 728 } 729 __catch(...) 730 { 731 _M_destroy_nodes(__nstart, __cur); 732 __throw_exception_again; 733 } 734 } 735 736 template<typename _Tp, typename _Alloc> 737 void 738 _Deque_base<_Tp, _Alloc>:: 739 _M_destroy_nodes(_Map_pointer __nstart, 740 _Map_pointer __nfinish) _GLIBCXX_NOEXCEPT 741 { 742 for (_Map_pointer __n = __nstart; __n < __nfinish; ++__n) 743 _M_deallocate_node(*__n); 744 } 745 746 /** 747 * @brief A standard container using fixed-size memory allocation and 748 * constant-time manipulation of elements at either end. 749 * 750 * @ingroup sequences 751 * 752 * @tparam _Tp Type of element. 753 * @tparam _Alloc Allocator type, defaults to allocator<_Tp>. 754 * 755 * Meets the requirements of a <a href="tables.html#65">container</a>, a 756 * <a href="tables.html#66">reversible container</a>, and a 757 * <a href="tables.html#67">sequence</a>, including the 758 * <a href="tables.html#68">optional sequence requirements</a>. 759 * 760 * In previous HP/SGI versions of deque, there was an extra template 761 * parameter so users could control the node size. This extension turned 762 * out to violate the C++ standard (it can be detected using template 763 * template parameters), and it was removed. 764 * 765 * Here's how a deque<Tp> manages memory. Each deque has 4 members: 766 * 767 * - Tp** _M_map 768 * - size_t _M_map_size 769 * - iterator _M_start, _M_finish 770 * 771 * map_size is at least 8. %map is an array of map_size 772 * pointers-to-@a nodes. (The name %map has nothing to do with the 773 * std::map class, and @b nodes should not be confused with 774 * std::list's usage of @a node.) 775 * 776 * A @a node has no specific type name as such, but it is referred 777 * to as @a node in this file. It is a simple array-of-Tp. If Tp 778 * is very large, there will be one Tp element per node (i.e., an 779 * @a array of one). For non-huge Tp's, node size is inversely 780 * related to Tp size: the larger the Tp, the fewer Tp's will fit 781 * in a node. The goal here is to keep the total size of a node 782 * relatively small and constant over different Tp's, to improve 783 * allocator efficiency. 784 * 785 * Not every pointer in the %map array will point to a node. If 786 * the initial number of elements in the deque is small, the 787 * /middle/ %map pointers will be valid, and the ones at the edges 788 * will be unused. This same situation will arise as the %map 789 * grows: available %map pointers, if any, will be on the ends. As 790 * new nodes are created, only a subset of the %map's pointers need 791 * to be copied @a outward. 792 * 793 * Class invariants: 794 * - For any nonsingular iterator i: 795 * - i.node points to a member of the %map array. (Yes, you read that 796 * correctly: i.node does not actually point to a node.) The member of 797 * the %map array is what actually points to the node. 798 * - i.first == *(i.node) (This points to the node (first Tp element).) 799 * - i.last == i.first + node_size 800 * - i.cur is a pointer in the range [i.first, i.last). NOTE: 801 * the implication of this is that i.cur is always a dereferenceable 802 * pointer, even if i is a past-the-end iterator. 803 * - Start and Finish are always nonsingular iterators. NOTE: this 804 * means that an empty deque must have one node, a deque with <N 805 * elements (where N is the node buffer size) must have one node, a 806 * deque with N through (2N-1) elements must have two nodes, etc. 807 * - For every node other than start.node and finish.node, every 808 * element in the node is an initialized object. If start.node == 809 * finish.node, then [start.cur, finish.cur) are initialized 810 * objects, and the elements outside that range are uninitialized 811 * storage. Otherwise, [start.cur, start.last) and [finish.first, 812 * finish.cur) are initialized objects, and [start.first, start.cur) 813 * and [finish.cur, finish.last) are uninitialized storage. 814 * - [%map, %map + map_size) is a valid, non-empty range. 815 * - [start.node, finish.node] is a valid range contained within 816 * [%map, %map + map_size). 817 * - A pointer in the range [%map, %map + map_size) points to an allocated 818 * node if and only if the pointer is in the range 819 * [start.node, finish.node]. 820 * 821 * Here's the magic: nothing in deque is @b aware of the discontiguous 822 * storage! 823 * 824 * The memory setup and layout occurs in the parent, _Base, and the iterator 825 * class is entirely responsible for @a leaping from one node to the next. 826 * All the implementation routines for deque itself work only through the 827 * start and finish iterators. This keeps the routines simple and sane, 828 * and we can use other standard algorithms as well. 829 */ 830 template<typename _Tp, typename _Alloc = std::allocator<_Tp> > 831 class deque : protected _Deque_base<_Tp, _Alloc> 832 { 833 #ifdef _GLIBCXX_CONCEPT_CHECKS 834 // concept requirements 835 typedef typename _Alloc::value_type _Alloc_value_type; 836 # if __cplusplus < 201103L 837 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 838 # endif 839 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept) 840 #endif 841 842 typedef _Deque_base<_Tp, _Alloc> _Base; 843 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type; 844 typedef typename _Base::_Alloc_traits _Alloc_traits; 845 typedef typename _Base::_Map_pointer _Map_pointer; 846 847 public: 848 typedef _Tp value_type; 849 typedef typename _Alloc_traits::pointer pointer; 850 typedef typename _Alloc_traits::const_pointer const_pointer; 851 typedef typename _Alloc_traits::reference reference; 852 typedef typename _Alloc_traits::const_reference const_reference; 853 typedef typename _Base::iterator iterator; 854 typedef typename _Base::const_iterator const_iterator; 855 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 856 typedef std::reverse_iterator<iterator> reverse_iterator; 857 typedef size_t size_type; 858 typedef ptrdiff_t difference_type; 859 typedef _Alloc allocator_type; 860 861 protected: 862 static size_t _S_buffer_size() _GLIBCXX_NOEXCEPT 863 { return __deque_buf_size(sizeof(_Tp)); } 864 865 // Functions controlling memory layout, and nothing else. 866 using _Base::_M_initialize_map; 867 using _Base::_M_create_nodes; 868 using _Base::_M_destroy_nodes; 869 using _Base::_M_allocate_node; 870 using _Base::_M_deallocate_node; 871 using _Base::_M_allocate_map; 872 using _Base::_M_deallocate_map; 873 using _Base::_M_get_Tp_allocator; 874 875 /** 876 * A total of four data members accumulated down the hierarchy. 877 * May be accessed via _M_impl.* 878 */ 879 using _Base::_M_impl; 880 881 public: 882 // [23.2.1.1] construct/copy/destroy 883 // (assign() and get_allocator() are also listed in this section) 884 885 /** 886 * @brief Creates a %deque with no elements. 887 */ 888 deque() : _Base() { } 889 890 /** 891 * @brief Creates a %deque with no elements. 892 * @param __a An allocator object. 893 */ 894 explicit 895 deque(const allocator_type& __a) 896 : _Base(__a, 0) { } 897 898 #if __cplusplus >= 201103L 899 /** 900 * @brief Creates a %deque with default constructed elements. 901 * @param __n The number of elements to initially create. 902 * @param __a An allocator. 903 * 904 * This constructor fills the %deque with @a n default 905 * constructed elements. 906 */ 907 explicit 908 deque(size_type __n, const allocator_type& __a = allocator_type()) 909 : _Base(__a, __n) 910 { _M_default_initialize(); } 911 912 /** 913 * @brief Creates a %deque with copies of an exemplar element. 914 * @param __n The number of elements to initially create. 915 * @param __value An element to copy. 916 * @param __a An allocator. 917 * 918 * This constructor fills the %deque with @a __n copies of @a __value. 919 */ 920 deque(size_type __n, const value_type& __value, 921 const allocator_type& __a = allocator_type()) 922 : _Base(__a, __n) 923 { _M_fill_initialize(__value); } 924 #else 925 /** 926 * @brief Creates a %deque with copies of an exemplar element. 927 * @param __n The number of elements to initially create. 928 * @param __value An element to copy. 929 * @param __a An allocator. 930 * 931 * This constructor fills the %deque with @a __n copies of @a __value. 932 */ 933 explicit 934 deque(size_type __n, const value_type& __value = value_type(), 935 const allocator_type& __a = allocator_type()) 936 : _Base(__a, __n) 937 { _M_fill_initialize(__value); } 938 #endif 939 940 /** 941 * @brief %Deque copy constructor. 942 * @param __x A %deque of identical element and allocator types. 943 * 944 * The newly-created %deque uses a copy of the allocator object used 945 * by @a __x (unless the allocator traits dictate a different object). 946 */ 947 deque(const deque& __x) 948 : _Base(_Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()), 949 __x.size()) 950 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 951 this->_M_impl._M_start, 952 _M_get_Tp_allocator()); } 953 954 #if __cplusplus >= 201103L 955 /** 956 * @brief %Deque move constructor. 957 * @param __x A %deque of identical element and allocator types. 958 * 959 * The newly-created %deque contains the exact contents of @a __x. 960 * The contents of @a __x are a valid, but unspecified %deque. 961 */ 962 deque(deque&& __x) 963 : _Base(std::move(__x)) { } 964 965 /// Copy constructor with alternative allocator 966 deque(const deque& __x, const allocator_type& __a) 967 : _Base(__a, __x.size()) 968 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 969 this->_M_impl._M_start, 970 _M_get_Tp_allocator()); } 971 972 /// Move constructor with alternative allocator 973 deque(deque&& __x, const allocator_type& __a) 974 : _Base(std::move(__x), __a, __x.size()) 975 { 976 if (__x.get_allocator() != __a) 977 { 978 std::__uninitialized_move_a(__x.begin(), __x.end(), 979 this->_M_impl._M_start, 980 _M_get_Tp_allocator()); 981 __x.clear(); 982 } 983 } 984 985 /** 986 * @brief Builds a %deque from an initializer list. 987 * @param __l An initializer_list. 988 * @param __a An allocator object. 989 * 990 * Create a %deque consisting of copies of the elements in the 991 * initializer_list @a __l. 992 * 993 * This will call the element type's copy constructor N times 994 * (where N is __l.size()) and do no memory reallocation. 995 */ 996 deque(initializer_list<value_type> __l, 997 const allocator_type& __a = allocator_type()) 998 : _Base(__a) 999 { 1000 _M_range_initialize(__l.begin(), __l.end(), 1001 random_access_iterator_tag()); 1002 } 1003 #endif 1004 1005 /** 1006 * @brief Builds a %deque from a range. 1007 * @param __first An input iterator. 1008 * @param __last An input iterator. 1009 * @param __a An allocator object. 1010 * 1011 * Create a %deque consisting of copies of the elements from [__first, 1012 * __last). 1013 * 1014 * If the iterators are forward, bidirectional, or random-access, then 1015 * this will call the elements' copy constructor N times (where N is 1016 * distance(__first,__last)) and do no memory reallocation. But if only 1017 * input iterators are used, then this will do at most 2N calls to the 1018 * copy constructor, and logN memory reallocations. 1019 */ 1020 #if __cplusplus >= 201103L 1021 template<typename _InputIterator, 1022 typename = std::_RequireInputIter<_InputIterator>> 1023 deque(_InputIterator __first, _InputIterator __last, 1024 const allocator_type& __a = allocator_type()) 1025 : _Base(__a) 1026 { _M_initialize_dispatch(__first, __last, __false_type()); } 1027 #else 1028 template<typename _InputIterator> 1029 deque(_InputIterator __first, _InputIterator __last, 1030 const allocator_type& __a = allocator_type()) 1031 : _Base(__a) 1032 { 1033 // Check whether it's an integral type. If so, it's not an iterator. 1034 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1035 _M_initialize_dispatch(__first, __last, _Integral()); 1036 } 1037 #endif 1038 1039 /** 1040 * The dtor only erases the elements, and note that if the elements 1041 * themselves are pointers, the pointed-to memory is not touched in any 1042 * way. Managing the pointer is the user's responsibility. 1043 */ 1044 ~deque() 1045 { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); } 1046 1047 /** 1048 * @brief %Deque assignment operator. 1049 * @param __x A %deque of identical element and allocator types. 1050 * 1051 * All the elements of @a x are copied. 1052 * 1053 * The newly-created %deque uses a copy of the allocator object used 1054 * by @a __x (unless the allocator traits dictate a different object). 1055 */ 1056 deque& 1057 operator=(const deque& __x); 1058 1059 #if __cplusplus >= 201103L 1060 /** 1061 * @brief %Deque move assignment operator. 1062 * @param __x A %deque of identical element and allocator types. 1063 * 1064 * The contents of @a __x are moved into this deque (without copying, 1065 * if the allocators permit it). 1066 * @a __x is a valid, but unspecified %deque. 1067 */ 1068 deque& 1069 operator=(deque&& __x) noexcept(_Alloc_traits::_S_always_equal()) 1070 { 1071 using __always_equal = typename _Alloc_traits::is_always_equal; 1072 _M_move_assign1(std::move(__x), __always_equal{}); 1073 return *this; 1074 } 1075 1076 /** 1077 * @brief Assigns an initializer list to a %deque. 1078 * @param __l An initializer_list. 1079 * 1080 * This function fills a %deque with copies of the elements in the 1081 * initializer_list @a __l. 1082 * 1083 * Note that the assignment completely changes the %deque and that the 1084 * resulting %deque's size is the same as the number of elements 1085 * assigned. 1086 */ 1087 deque& 1088 operator=(initializer_list<value_type> __l) 1089 { 1090 _M_assign_aux(__l.begin(), __l.end(), 1091 random_access_iterator_tag()); 1092 return *this; 1093 } 1094 #endif 1095 1096 /** 1097 * @brief Assigns a given value to a %deque. 1098 * @param __n Number of elements to be assigned. 1099 * @param __val Value to be assigned. 1100 * 1101 * This function fills a %deque with @a n copies of the given 1102 * value. Note that the assignment completely changes the 1103 * %deque and that the resulting %deque's size is the same as 1104 * the number of elements assigned. 1105 */ 1106 void 1107 assign(size_type __n, const value_type& __val) 1108 { _M_fill_assign(__n, __val); } 1109 1110 /** 1111 * @brief Assigns a range to a %deque. 1112 * @param __first An input iterator. 1113 * @param __last An input iterator. 1114 * 1115 * This function fills a %deque with copies of the elements in the 1116 * range [__first,__last). 1117 * 1118 * Note that the assignment completely changes the %deque and that the 1119 * resulting %deque's size is the same as the number of elements 1120 * assigned. 1121 */ 1122 #if __cplusplus >= 201103L 1123 template<typename _InputIterator, 1124 typename = std::_RequireInputIter<_InputIterator>> 1125 void 1126 assign(_InputIterator __first, _InputIterator __last) 1127 { _M_assign_dispatch(__first, __last, __false_type()); } 1128 #else 1129 template<typename _InputIterator> 1130 void 1131 assign(_InputIterator __first, _InputIterator __last) 1132 { 1133 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1134 _M_assign_dispatch(__first, __last, _Integral()); 1135 } 1136 #endif 1137 1138 #if __cplusplus >= 201103L 1139 /** 1140 * @brief Assigns an initializer list to a %deque. 1141 * @param __l An initializer_list. 1142 * 1143 * This function fills a %deque with copies of the elements in the 1144 * initializer_list @a __l. 1145 * 1146 * Note that the assignment completely changes the %deque and that the 1147 * resulting %deque's size is the same as the number of elements 1148 * assigned. 1149 */ 1150 void 1151 assign(initializer_list<value_type> __l) 1152 { _M_assign_aux(__l.begin(), __l.end(), random_access_iterator_tag()); } 1153 #endif 1154 1155 /// Get a copy of the memory allocation object. 1156 allocator_type 1157 get_allocator() const _GLIBCXX_NOEXCEPT 1158 { return _Base::get_allocator(); } 1159 1160 // iterators 1161 /** 1162 * Returns a read/write iterator that points to the first element in the 1163 * %deque. Iteration is done in ordinary element order. 1164 */ 1165 iterator 1166 begin() _GLIBCXX_NOEXCEPT 1167 { return this->_M_impl._M_start; } 1168 1169 /** 1170 * Returns a read-only (constant) iterator that points to the first 1171 * element in the %deque. Iteration is done in ordinary element order. 1172 */ 1173 const_iterator 1174 begin() const _GLIBCXX_NOEXCEPT 1175 { return this->_M_impl._M_start; } 1176 1177 /** 1178 * Returns a read/write iterator that points one past the last 1179 * element in the %deque. Iteration is done in ordinary 1180 * element order. 1181 */ 1182 iterator 1183 end() _GLIBCXX_NOEXCEPT 1184 { return this->_M_impl._M_finish; } 1185 1186 /** 1187 * Returns a read-only (constant) iterator that points one past 1188 * the last element in the %deque. Iteration is done in 1189 * ordinary element order. 1190 */ 1191 const_iterator 1192 end() const _GLIBCXX_NOEXCEPT 1193 { return this->_M_impl._M_finish; } 1194 1195 /** 1196 * Returns a read/write reverse iterator that points to the 1197 * last element in the %deque. Iteration is done in reverse 1198 * element order. 1199 */ 1200 reverse_iterator 1201 rbegin() _GLIBCXX_NOEXCEPT 1202 { return reverse_iterator(this->_M_impl._M_finish); } 1203 1204 /** 1205 * Returns a read-only (constant) reverse iterator that points 1206 * to the last element in the %deque. Iteration is done in 1207 * reverse element order. 1208 */ 1209 const_reverse_iterator 1210 rbegin() const _GLIBCXX_NOEXCEPT 1211 { return const_reverse_iterator(this->_M_impl._M_finish); } 1212 1213 /** 1214 * Returns a read/write reverse iterator that points to one 1215 * before the first element in the %deque. Iteration is done 1216 * in reverse element order. 1217 */ 1218 reverse_iterator 1219 rend() _GLIBCXX_NOEXCEPT 1220 { return reverse_iterator(this->_M_impl._M_start); } 1221 1222 /** 1223 * Returns a read-only (constant) reverse iterator that points 1224 * to one before the first element in the %deque. Iteration is 1225 * done in reverse element order. 1226 */ 1227 const_reverse_iterator 1228 rend() const _GLIBCXX_NOEXCEPT 1229 { return const_reverse_iterator(this->_M_impl._M_start); } 1230 1231 #if __cplusplus >= 201103L 1232 /** 1233 * Returns a read-only (constant) iterator that points to the first 1234 * element in the %deque. Iteration is done in ordinary element order. 1235 */ 1236 const_iterator 1237 cbegin() const noexcept 1238 { return this->_M_impl._M_start; } 1239 1240 /** 1241 * Returns a read-only (constant) iterator that points one past 1242 * the last element in the %deque. Iteration is done in 1243 * ordinary element order. 1244 */ 1245 const_iterator 1246 cend() const noexcept 1247 { return this->_M_impl._M_finish; } 1248 1249 /** 1250 * Returns a read-only (constant) reverse iterator that points 1251 * to the last element in the %deque. Iteration is done in 1252 * reverse element order. 1253 */ 1254 const_reverse_iterator 1255 crbegin() const noexcept 1256 { return const_reverse_iterator(this->_M_impl._M_finish); } 1257 1258 /** 1259 * Returns a read-only (constant) reverse iterator that points 1260 * to one before the first element in the %deque. Iteration is 1261 * done in reverse element order. 1262 */ 1263 const_reverse_iterator 1264 crend() const noexcept 1265 { return const_reverse_iterator(this->_M_impl._M_start); } 1266 #endif 1267 1268 // [23.2.1.2] capacity 1269 /** Returns the number of elements in the %deque. */ 1270 size_type 1271 size() const _GLIBCXX_NOEXCEPT 1272 { return this->_M_impl._M_finish - this->_M_impl._M_start; } 1273 1274 /** Returns the size() of the largest possible %deque. */ 1275 size_type 1276 max_size() const _GLIBCXX_NOEXCEPT 1277 { return _Alloc_traits::max_size(_M_get_Tp_allocator()); } 1278 1279 #if __cplusplus >= 201103L 1280 /** 1281 * @brief Resizes the %deque to the specified number of elements. 1282 * @param __new_size Number of elements the %deque should contain. 1283 * 1284 * This function will %resize the %deque to the specified 1285 * number of elements. If the number is smaller than the 1286 * %deque's current size the %deque is truncated, otherwise 1287 * default constructed elements are appended. 1288 */ 1289 void 1290 resize(size_type __new_size) 1291 { 1292 const size_type __len = size(); 1293 if (__new_size > __len) 1294 _M_default_append(__new_size - __len); 1295 else if (__new_size < __len) 1296 _M_erase_at_end(this->_M_impl._M_start 1297 + difference_type(__new_size)); 1298 } 1299 1300 /** 1301 * @brief Resizes the %deque to the specified number of elements. 1302 * @param __new_size Number of elements the %deque should contain. 1303 * @param __x Data with which new elements should be populated. 1304 * 1305 * This function will %resize the %deque to the specified 1306 * number of elements. If the number is smaller than the 1307 * %deque's current size the %deque is truncated, otherwise the 1308 * %deque is extended and new elements are populated with given 1309 * data. 1310 */ 1311 void 1312 resize(size_type __new_size, const value_type& __x) 1313 { 1314 const size_type __len = size(); 1315 if (__new_size > __len) 1316 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1317 else if (__new_size < __len) 1318 _M_erase_at_end(this->_M_impl._M_start 1319 + difference_type(__new_size)); 1320 } 1321 #else 1322 /** 1323 * @brief Resizes the %deque to the specified number of elements. 1324 * @param __new_size Number of elements the %deque should contain. 1325 * @param __x Data with which new elements should be populated. 1326 * 1327 * This function will %resize the %deque to the specified 1328 * number of elements. If the number is smaller than the 1329 * %deque's current size the %deque is truncated, otherwise the 1330 * %deque is extended and new elements are populated with given 1331 * data. 1332 */ 1333 void 1334 resize(size_type __new_size, value_type __x = value_type()) 1335 { 1336 const size_type __len = size(); 1337 if (__new_size > __len) 1338 _M_fill_insert(this->_M_impl._M_finish, __new_size - __len, __x); 1339 else if (__new_size < __len) 1340 _M_erase_at_end(this->_M_impl._M_start 1341 + difference_type(__new_size)); 1342 } 1343 #endif 1344 1345 #if __cplusplus >= 201103L 1346 /** A non-binding request to reduce memory use. */ 1347 void 1348 shrink_to_fit() noexcept 1349 { _M_shrink_to_fit(); } 1350 #endif 1351 1352 /** 1353 * Returns true if the %deque is empty. (Thus begin() would 1354 * equal end().) 1355 */ 1356 bool 1357 empty() const _GLIBCXX_NOEXCEPT 1358 { return this->_M_impl._M_finish == this->_M_impl._M_start; } 1359 1360 // element access 1361 /** 1362 * @brief Subscript access to the data contained in the %deque. 1363 * @param __n The index of the element for which data should be 1364 * accessed. 1365 * @return Read/write reference to data. 1366 * 1367 * This operator allows for easy, array-style, data access. 1368 * Note that data access with this operator is unchecked and 1369 * out_of_range lookups are not defined. (For checked lookups 1370 * see at().) 1371 */ 1372 reference 1373 operator[](size_type __n) _GLIBCXX_NOEXCEPT 1374 { 1375 __glibcxx_requires_subscript(__n); 1376 return this->_M_impl._M_start[difference_type(__n)]; 1377 } 1378 1379 /** 1380 * @brief Subscript access to the data contained in the %deque. 1381 * @param __n The index of the element for which data should be 1382 * accessed. 1383 * @return Read-only (constant) reference to data. 1384 * 1385 * This operator allows for easy, array-style, data access. 1386 * Note that data access with this operator is unchecked and 1387 * out_of_range lookups are not defined. (For checked lookups 1388 * see at().) 1389 */ 1390 const_reference 1391 operator[](size_type __n) const _GLIBCXX_NOEXCEPT 1392 { 1393 __glibcxx_requires_subscript(__n); 1394 return this->_M_impl._M_start[difference_type(__n)]; 1395 } 1396 1397 protected: 1398 /// Safety check used only from at(). 1399 void 1400 _M_range_check(size_type __n) const 1401 { 1402 if (__n >= this->size()) 1403 __throw_out_of_range_fmt(__N("deque::_M_range_check: __n " 1404 "(which is %zu)>= this->size() " 1405 "(which is %zu)"), 1406 __n, this->size()); 1407 } 1408 1409 public: 1410 /** 1411 * @brief Provides access to the data contained in the %deque. 1412 * @param __n The index of the element for which data should be 1413 * accessed. 1414 * @return Read/write reference to data. 1415 * @throw std::out_of_range If @a __n is an invalid index. 1416 * 1417 * This function provides for safer data access. The parameter 1418 * is first checked that it is in the range of the deque. The 1419 * function throws out_of_range if the check fails. 1420 */ 1421 reference 1422 at(size_type __n) 1423 { 1424 _M_range_check(__n); 1425 return (*this)[__n]; 1426 } 1427 1428 /** 1429 * @brief Provides access to the data contained in the %deque. 1430 * @param __n The index of the element for which data should be 1431 * accessed. 1432 * @return Read-only (constant) reference to data. 1433 * @throw std::out_of_range If @a __n is an invalid index. 1434 * 1435 * This function provides for safer data access. The parameter is first 1436 * checked that it is in the range of the deque. The function throws 1437 * out_of_range if the check fails. 1438 */ 1439 const_reference 1440 at(size_type __n) const 1441 { 1442 _M_range_check(__n); 1443 return (*this)[__n]; 1444 } 1445 1446 /** 1447 * Returns a read/write reference to the data at the first 1448 * element of the %deque. 1449 */ 1450 reference 1451 front() _GLIBCXX_NOEXCEPT 1452 { 1453 __glibcxx_requires_nonempty(); 1454 return *begin(); 1455 } 1456 1457 /** 1458 * Returns a read-only (constant) reference to the data at the first 1459 * element of the %deque. 1460 */ 1461 const_reference 1462 front() const _GLIBCXX_NOEXCEPT 1463 { 1464 __glibcxx_requires_nonempty(); 1465 return *begin(); 1466 } 1467 1468 /** 1469 * Returns a read/write reference to the data at the last element of the 1470 * %deque. 1471 */ 1472 reference 1473 back() _GLIBCXX_NOEXCEPT 1474 { 1475 __glibcxx_requires_nonempty(); 1476 iterator __tmp = end(); 1477 --__tmp; 1478 return *__tmp; 1479 } 1480 1481 /** 1482 * Returns a read-only (constant) reference to the data at the last 1483 * element of the %deque. 1484 */ 1485 const_reference 1486 back() const _GLIBCXX_NOEXCEPT 1487 { 1488 __glibcxx_requires_nonempty(); 1489 const_iterator __tmp = end(); 1490 --__tmp; 1491 return *__tmp; 1492 } 1493 1494 // [23.2.1.2] modifiers 1495 /** 1496 * @brief Add data to the front of the %deque. 1497 * @param __x Data to be added. 1498 * 1499 * This is a typical stack operation. The function creates an 1500 * element at the front of the %deque and assigns the given 1501 * data to it. Due to the nature of a %deque this operation 1502 * can be done in constant time. 1503 */ 1504 void 1505 push_front(const value_type& __x) 1506 { 1507 if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first) 1508 { 1509 _Alloc_traits::construct(this->_M_impl, 1510 this->_M_impl._M_start._M_cur - 1, 1511 __x); 1512 --this->_M_impl._M_start._M_cur; 1513 } 1514 else 1515 _M_push_front_aux(__x); 1516 } 1517 1518 #if __cplusplus >= 201103L 1519 void 1520 push_front(value_type&& __x) 1521 { emplace_front(std::move(__x)); } 1522 1523 template<typename... _Args> 1524 #if __cplusplus > 201402L 1525 reference 1526 #else 1527 void 1528 #endif 1529 emplace_front(_Args&&... __args); 1530 #endif 1531 1532 /** 1533 * @brief Add data to the end of the %deque. 1534 * @param __x Data to be added. 1535 * 1536 * This is a typical stack operation. The function creates an 1537 * element at the end of the %deque and assigns the given data 1538 * to it. Due to the nature of a %deque this operation can be 1539 * done in constant time. 1540 */ 1541 void 1542 push_back(const value_type& __x) 1543 { 1544 if (this->_M_impl._M_finish._M_cur 1545 != this->_M_impl._M_finish._M_last - 1) 1546 { 1547 _Alloc_traits::construct(this->_M_impl, 1548 this->_M_impl._M_finish._M_cur, __x); 1549 ++this->_M_impl._M_finish._M_cur; 1550 } 1551 else 1552 _M_push_back_aux(__x); 1553 } 1554 1555 #if __cplusplus >= 201103L 1556 void 1557 push_back(value_type&& __x) 1558 { emplace_back(std::move(__x)); } 1559 1560 template<typename... _Args> 1561 #if __cplusplus > 201402L 1562 reference 1563 #else 1564 void 1565 #endif 1566 emplace_back(_Args&&... __args); 1567 #endif 1568 1569 /** 1570 * @brief Removes first element. 1571 * 1572 * This is a typical stack operation. It shrinks the %deque by one. 1573 * 1574 * Note that no data is returned, and if the first element's data is 1575 * needed, it should be retrieved before pop_front() is called. 1576 */ 1577 void 1578 pop_front() _GLIBCXX_NOEXCEPT 1579 { 1580 __glibcxx_requires_nonempty(); 1581 if (this->_M_impl._M_start._M_cur 1582 != this->_M_impl._M_start._M_last - 1) 1583 { 1584 _Alloc_traits::destroy(this->_M_impl, 1585 this->_M_impl._M_start._M_cur); 1586 ++this->_M_impl._M_start._M_cur; 1587 } 1588 else 1589 _M_pop_front_aux(); 1590 } 1591 1592 /** 1593 * @brief Removes last element. 1594 * 1595 * This is a typical stack operation. It shrinks the %deque by one. 1596 * 1597 * Note that no data is returned, and if the last element's data is 1598 * needed, it should be retrieved before pop_back() is called. 1599 */ 1600 void 1601 pop_back() _GLIBCXX_NOEXCEPT 1602 { 1603 __glibcxx_requires_nonempty(); 1604 if (this->_M_impl._M_finish._M_cur 1605 != this->_M_impl._M_finish._M_first) 1606 { 1607 --this->_M_impl._M_finish._M_cur; 1608 _Alloc_traits::destroy(this->_M_impl, 1609 this->_M_impl._M_finish._M_cur); 1610 } 1611 else 1612 _M_pop_back_aux(); 1613 } 1614 1615 #if __cplusplus >= 201103L 1616 /** 1617 * @brief Inserts an object in %deque before specified iterator. 1618 * @param __position A const_iterator into the %deque. 1619 * @param __args Arguments. 1620 * @return An iterator that points to the inserted data. 1621 * 1622 * This function will insert an object of type T constructed 1623 * with T(std::forward<Args>(args)...) before the specified location. 1624 */ 1625 template<typename... _Args> 1626 iterator 1627 emplace(const_iterator __position, _Args&&... __args); 1628 1629 /** 1630 * @brief Inserts given value into %deque before specified iterator. 1631 * @param __position A const_iterator into the %deque. 1632 * @param __x Data to be inserted. 1633 * @return An iterator that points to the inserted data. 1634 * 1635 * This function will insert a copy of the given value before the 1636 * specified location. 1637 */ 1638 iterator 1639 insert(const_iterator __position, const value_type& __x); 1640 #else 1641 /** 1642 * @brief Inserts given value into %deque before specified iterator. 1643 * @param __position An iterator into the %deque. 1644 * @param __x Data to be inserted. 1645 * @return An iterator that points to the inserted data. 1646 * 1647 * This function will insert a copy of the given value before the 1648 * specified location. 1649 */ 1650 iterator 1651 insert(iterator __position, const value_type& __x); 1652 #endif 1653 1654 #if __cplusplus >= 201103L 1655 /** 1656 * @brief Inserts given rvalue into %deque before specified iterator. 1657 * @param __position A const_iterator into the %deque. 1658 * @param __x Data to be inserted. 1659 * @return An iterator that points to the inserted data. 1660 * 1661 * This function will insert a copy of the given rvalue before the 1662 * specified location. 1663 */ 1664 iterator 1665 insert(const_iterator __position, value_type&& __x) 1666 { return emplace(__position, std::move(__x)); } 1667 1668 /** 1669 * @brief Inserts an initializer list into the %deque. 1670 * @param __p An iterator into the %deque. 1671 * @param __l An initializer_list. 1672 * 1673 * This function will insert copies of the data in the 1674 * initializer_list @a __l into the %deque before the location 1675 * specified by @a __p. This is known as <em>list insert</em>. 1676 */ 1677 iterator 1678 insert(const_iterator __p, initializer_list<value_type> __l) 1679 { 1680 auto __offset = __p - cbegin(); 1681 _M_range_insert_aux(__p._M_const_cast(), __l.begin(), __l.end(), 1682 std::random_access_iterator_tag()); 1683 return begin() + __offset; 1684 } 1685 #endif 1686 1687 #if __cplusplus >= 201103L 1688 /** 1689 * @brief Inserts a number of copies of given data into the %deque. 1690 * @param __position A const_iterator into the %deque. 1691 * @param __n Number of elements to be inserted. 1692 * @param __x Data to be inserted. 1693 * @return An iterator that points to the inserted data. 1694 * 1695 * This function will insert a specified number of copies of the given 1696 * data before the location specified by @a __position. 1697 */ 1698 iterator 1699 insert(const_iterator __position, size_type __n, const value_type& __x) 1700 { 1701 difference_type __offset = __position - cbegin(); 1702 _M_fill_insert(__position._M_const_cast(), __n, __x); 1703 return begin() + __offset; 1704 } 1705 #else 1706 /** 1707 * @brief Inserts a number of copies of given data into the %deque. 1708 * @param __position An iterator into the %deque. 1709 * @param __n Number of elements to be inserted. 1710 * @param __x Data to be inserted. 1711 * 1712 * This function will insert a specified number of copies of the given 1713 * data before the location specified by @a __position. 1714 */ 1715 void 1716 insert(iterator __position, size_type __n, const value_type& __x) 1717 { _M_fill_insert(__position, __n, __x); } 1718 #endif 1719 1720 #if __cplusplus >= 201103L 1721 /** 1722 * @brief Inserts a range into the %deque. 1723 * @param __position A const_iterator into the %deque. 1724 * @param __first An input iterator. 1725 * @param __last An input iterator. 1726 * @return An iterator that points to the inserted data. 1727 * 1728 * This function will insert copies of the data in the range 1729 * [__first,__last) into the %deque before the location specified 1730 * by @a __position. This is known as <em>range insert</em>. 1731 */ 1732 template<typename _InputIterator, 1733 typename = std::_RequireInputIter<_InputIterator>> 1734 iterator 1735 insert(const_iterator __position, _InputIterator __first, 1736 _InputIterator __last) 1737 { 1738 difference_type __offset = __position - cbegin(); 1739 _M_insert_dispatch(__position._M_const_cast(), 1740 __first, __last, __false_type()); 1741 return begin() + __offset; 1742 } 1743 #else 1744 /** 1745 * @brief Inserts a range into the %deque. 1746 * @param __position An iterator into the %deque. 1747 * @param __first An input iterator. 1748 * @param __last An input iterator. 1749 * 1750 * This function will insert copies of the data in the range 1751 * [__first,__last) into the %deque before the location specified 1752 * by @a __position. This is known as <em>range insert</em>. 1753 */ 1754 template<typename _InputIterator> 1755 void 1756 insert(iterator __position, _InputIterator __first, 1757 _InputIterator __last) 1758 { 1759 // Check whether it's an integral type. If so, it's not an iterator. 1760 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1761 _M_insert_dispatch(__position, __first, __last, _Integral()); 1762 } 1763 #endif 1764 1765 /** 1766 * @brief Remove element at given position. 1767 * @param __position Iterator pointing to element to be erased. 1768 * @return An iterator pointing to the next element (or end()). 1769 * 1770 * This function will erase the element at the given position and thus 1771 * shorten the %deque by one. 1772 * 1773 * The user is cautioned that 1774 * this function only erases the element, and that if the element is 1775 * itself a pointer, the pointed-to memory is not touched in any way. 1776 * Managing the pointer is the user's responsibility. 1777 */ 1778 iterator 1779 #if __cplusplus >= 201103L 1780 erase(const_iterator __position) 1781 #else 1782 erase(iterator __position) 1783 #endif 1784 { return _M_erase(__position._M_const_cast()); } 1785 1786 /** 1787 * @brief Remove a range of elements. 1788 * @param __first Iterator pointing to the first element to be erased. 1789 * @param __last Iterator pointing to one past the last element to be 1790 * erased. 1791 * @return An iterator pointing to the element pointed to by @a last 1792 * prior to erasing (or end()). 1793 * 1794 * This function will erase the elements in the range 1795 * [__first,__last) and shorten the %deque accordingly. 1796 * 1797 * The user is cautioned that 1798 * this function only erases the elements, and that if the elements 1799 * themselves are pointers, the pointed-to memory is not touched in any 1800 * way. Managing the pointer is the user's responsibility. 1801 */ 1802 iterator 1803 #if __cplusplus >= 201103L 1804 erase(const_iterator __first, const_iterator __last) 1805 #else 1806 erase(iterator __first, iterator __last) 1807 #endif 1808 { return _M_erase(__first._M_const_cast(), __last._M_const_cast()); } 1809 1810 /** 1811 * @brief Swaps data with another %deque. 1812 * @param __x A %deque of the same element and allocator types. 1813 * 1814 * This exchanges the elements between two deques in constant time. 1815 * (Four pointers, so it should be quite fast.) 1816 * Note that the global std::swap() function is specialized such that 1817 * std::swap(d1,d2) will feed to this function. 1818 * 1819 * Whether the allocators are swapped depends on the allocator traits. 1820 */ 1821 void 1822 swap(deque& __x) _GLIBCXX_NOEXCEPT 1823 { 1824 #if __cplusplus >= 201103L 1825 __glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value 1826 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator()); 1827 #endif 1828 _M_impl._M_swap_data(__x._M_impl); 1829 _Alloc_traits::_S_on_swap(_M_get_Tp_allocator(), 1830 __x._M_get_Tp_allocator()); 1831 } 1832 1833 /** 1834 * Erases all the elements. Note that this function only erases the 1835 * elements, and that if the elements themselves are pointers, the 1836 * pointed-to memory is not touched in any way. Managing the pointer is 1837 * the user's responsibility. 1838 */ 1839 void 1840 clear() _GLIBCXX_NOEXCEPT 1841 { _M_erase_at_end(begin()); } 1842 1843 protected: 1844 // Internal constructor functions follow. 1845 1846 // called by the range constructor to implement [23.1.1]/9 1847 1848 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1849 // 438. Ambiguity in the "do the right thing" clause 1850 template<typename _Integer> 1851 void 1852 _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type) 1853 { 1854 _M_initialize_map(static_cast<size_type>(__n)); 1855 _M_fill_initialize(__x); 1856 } 1857 1858 // called by the range constructor to implement [23.1.1]/9 1859 template<typename _InputIterator> 1860 void 1861 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last, 1862 __false_type) 1863 { 1864 _M_range_initialize(__first, __last, 1865 std::__iterator_category(__first)); 1866 } 1867 1868 // called by the second initialize_dispatch above 1869 //@{ 1870 /** 1871 * @brief Fills the deque with whatever is in [first,last). 1872 * @param __first An input iterator. 1873 * @param __last An input iterator. 1874 * @return Nothing. 1875 * 1876 * If the iterators are actually forward iterators (or better), then the 1877 * memory layout can be done all at once. Else we move forward using 1878 * push_back on each value from the iterator. 1879 */ 1880 template<typename _InputIterator> 1881 void 1882 _M_range_initialize(_InputIterator __first, _InputIterator __last, 1883 std::input_iterator_tag); 1884 1885 // called by the second initialize_dispatch above 1886 template<typename _ForwardIterator> 1887 void 1888 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last, 1889 std::forward_iterator_tag); 1890 //@} 1891 1892 /** 1893 * @brief Fills the %deque with copies of value. 1894 * @param __value Initial value. 1895 * @return Nothing. 1896 * @pre _M_start and _M_finish have already been initialized, 1897 * but none of the %deque's elements have yet been constructed. 1898 * 1899 * This function is called only when the user provides an explicit size 1900 * (with or without an explicit exemplar value). 1901 */ 1902 void 1903 _M_fill_initialize(const value_type& __value); 1904 1905 #if __cplusplus >= 201103L 1906 // called by deque(n). 1907 void 1908 _M_default_initialize(); 1909 #endif 1910 1911 // Internal assign functions follow. The *_aux functions do the actual 1912 // assignment work for the range versions. 1913 1914 // called by the range assign to implement [23.1.1]/9 1915 1916 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1917 // 438. Ambiguity in the "do the right thing" clause 1918 template<typename _Integer> 1919 void 1920 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) 1921 { _M_fill_assign(__n, __val); } 1922 1923 // called by the range assign to implement [23.1.1]/9 1924 template<typename _InputIterator> 1925 void 1926 _M_assign_dispatch(_InputIterator __first, _InputIterator __last, 1927 __false_type) 1928 { _M_assign_aux(__first, __last, std::__iterator_category(__first)); } 1929 1930 // called by the second assign_dispatch above 1931 template<typename _InputIterator> 1932 void 1933 _M_assign_aux(_InputIterator __first, _InputIterator __last, 1934 std::input_iterator_tag); 1935 1936 // called by the second assign_dispatch above 1937 template<typename _ForwardIterator> 1938 void 1939 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last, 1940 std::forward_iterator_tag) 1941 { 1942 const size_type __len = std::distance(__first, __last); 1943 if (__len > size()) 1944 { 1945 _ForwardIterator __mid = __first; 1946 std::advance(__mid, size()); 1947 std::copy(__first, __mid, begin()); 1948 _M_range_insert_aux(end(), __mid, __last, 1949 std::__iterator_category(__first)); 1950 } 1951 else 1952 _M_erase_at_end(std::copy(__first, __last, begin())); 1953 } 1954 1955 // Called by assign(n,t), and the range assign when it turns out 1956 // to be the same thing. 1957 void 1958 _M_fill_assign(size_type __n, const value_type& __val) 1959 { 1960 if (__n > size()) 1961 { 1962 std::fill(begin(), end(), __val); 1963 _M_fill_insert(end(), __n - size(), __val); 1964 } 1965 else 1966 { 1967 _M_erase_at_end(begin() + difference_type(__n)); 1968 std::fill(begin(), end(), __val); 1969 } 1970 } 1971 1972 //@{ 1973 /// Helper functions for push_* and pop_*. 1974 #if __cplusplus < 201103L 1975 void _M_push_back_aux(const value_type&); 1976 1977 void _M_push_front_aux(const value_type&); 1978 #else 1979 template<typename... _Args> 1980 void _M_push_back_aux(_Args&&... __args); 1981 1982 template<typename... _Args> 1983 void _M_push_front_aux(_Args&&... __args); 1984 #endif 1985 1986 void _M_pop_back_aux(); 1987 1988 void _M_pop_front_aux(); 1989 //@} 1990 1991 // Internal insert functions follow. The *_aux functions do the actual 1992 // insertion work when all shortcuts fail. 1993 1994 // called by the range insert to implement [23.1.1]/9 1995 1996 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1997 // 438. Ambiguity in the "do the right thing" clause 1998 template<typename _Integer> 1999 void 2000 _M_insert_dispatch(iterator __pos, 2001 _Integer __n, _Integer __x, __true_type) 2002 { _M_fill_insert(__pos, __n, __x); } 2003 2004 // called by the range insert to implement [23.1.1]/9 2005 template<typename _InputIterator> 2006 void 2007 _M_insert_dispatch(iterator __pos, 2008 _InputIterator __first, _InputIterator __last, 2009 __false_type) 2010 { 2011 _M_range_insert_aux(__pos, __first, __last, 2012 std::__iterator_category(__first)); 2013 } 2014 2015 // called by the second insert_dispatch above 2016 template<typename _InputIterator> 2017 void 2018 _M_range_insert_aux(iterator __pos, _InputIterator __first, 2019 _InputIterator __last, std::input_iterator_tag); 2020 2021 // called by the second insert_dispatch above 2022 template<typename _ForwardIterator> 2023 void 2024 _M_range_insert_aux(iterator __pos, _ForwardIterator __first, 2025 _ForwardIterator __last, std::forward_iterator_tag); 2026 2027 // Called by insert(p,n,x), and the range insert when it turns out to be 2028 // the same thing. Can use fill functions in optimal situations, 2029 // otherwise passes off to insert_aux(p,n,x). 2030 void 2031 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x); 2032 2033 // called by insert(p,x) 2034 #if __cplusplus < 201103L 2035 iterator 2036 _M_insert_aux(iterator __pos, const value_type& __x); 2037 #else 2038 template<typename... _Args> 2039 iterator 2040 _M_insert_aux(iterator __pos, _Args&&... __args); 2041 #endif 2042 2043 // called by insert(p,n,x) via fill_insert 2044 void 2045 _M_insert_aux(iterator __pos, size_type __n, const value_type& __x); 2046 2047 // called by range_insert_aux for forward iterators 2048 template<typename _ForwardIterator> 2049 void 2050 _M_insert_aux(iterator __pos, 2051 _ForwardIterator __first, _ForwardIterator __last, 2052 size_type __n); 2053 2054 2055 // Internal erase functions follow. 2056 2057 void 2058 _M_destroy_data_aux(iterator __first, iterator __last); 2059 2060 // Called by ~deque(). 2061 // NB: Doesn't deallocate the nodes. 2062 template<typename _Alloc1> 2063 void 2064 _M_destroy_data(iterator __first, iterator __last, const _Alloc1&) 2065 { _M_destroy_data_aux(__first, __last); } 2066 2067 void 2068 _M_destroy_data(iterator __first, iterator __last, 2069 const std::allocator<_Tp>&) 2070 { 2071 if (!__has_trivial_destructor(value_type)) 2072 _M_destroy_data_aux(__first, __last); 2073 } 2074 2075 // Called by erase(q1, q2). 2076 void 2077 _M_erase_at_begin(iterator __pos) 2078 { 2079 _M_destroy_data(begin(), __pos, _M_get_Tp_allocator()); 2080 _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node); 2081 this->_M_impl._M_start = __pos; 2082 } 2083 2084 // Called by erase(q1, q2), resize(), clear(), _M_assign_aux, 2085 // _M_fill_assign, operator=. 2086 void 2087 _M_erase_at_end(iterator __pos) 2088 { 2089 _M_destroy_data(__pos, end(), _M_get_Tp_allocator()); 2090 _M_destroy_nodes(__pos._M_node + 1, 2091 this->_M_impl._M_finish._M_node + 1); 2092 this->_M_impl._M_finish = __pos; 2093 } 2094 2095 iterator 2096 _M_erase(iterator __pos); 2097 2098 iterator 2099 _M_erase(iterator __first, iterator __last); 2100 2101 #if __cplusplus >= 201103L 2102 // Called by resize(sz). 2103 void 2104 _M_default_append(size_type __n); 2105 2106 bool 2107 _M_shrink_to_fit(); 2108 #endif 2109 2110 //@{ 2111 /// Memory-handling helpers for the previous internal insert functions. 2112 iterator 2113 _M_reserve_elements_at_front(size_type __n) 2114 { 2115 const size_type __vacancies = this->_M_impl._M_start._M_cur 2116 - this->_M_impl._M_start._M_first; 2117 if (__n > __vacancies) 2118 _M_new_elements_at_front(__n - __vacancies); 2119 return this->_M_impl._M_start - difference_type(__n); 2120 } 2121 2122 iterator 2123 _M_reserve_elements_at_back(size_type __n) 2124 { 2125 const size_type __vacancies = (this->_M_impl._M_finish._M_last 2126 - this->_M_impl._M_finish._M_cur) - 1; 2127 if (__n > __vacancies) 2128 _M_new_elements_at_back(__n - __vacancies); 2129 return this->_M_impl._M_finish + difference_type(__n); 2130 } 2131 2132 void 2133 _M_new_elements_at_front(size_type __new_elements); 2134 2135 void 2136 _M_new_elements_at_back(size_type __new_elements); 2137 //@} 2138 2139 2140 //@{ 2141 /** 2142 * @brief Memory-handling helpers for the major %map. 2143 * 2144 * Makes sure the _M_map has space for new nodes. Does not 2145 * actually add the nodes. Can invalidate _M_map pointers. 2146 * (And consequently, %deque iterators.) 2147 */ 2148 void 2149 _M_reserve_map_at_back(size_type __nodes_to_add = 1) 2150 { 2151 if (__nodes_to_add + 1 > this->_M_impl._M_map_size 2152 - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map)) 2153 _M_reallocate_map(__nodes_to_add, false); 2154 } 2155 2156 void 2157 _M_reserve_map_at_front(size_type __nodes_to_add = 1) 2158 { 2159 if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node 2160 - this->_M_impl._M_map)) 2161 _M_reallocate_map(__nodes_to_add, true); 2162 } 2163 2164 void 2165 _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front); 2166 //@} 2167 2168 #if __cplusplus >= 201103L 2169 // Constant-time, nothrow move assignment when source object's memory 2170 // can be moved because the allocators are equal. 2171 void 2172 _M_move_assign1(deque&& __x, /* always equal: */ true_type) noexcept 2173 { 2174 this->_M_impl._M_swap_data(__x._M_impl); 2175 __x.clear(); 2176 std::__alloc_on_move(_M_get_Tp_allocator(), __x._M_get_Tp_allocator()); 2177 } 2178 2179 // When the allocators are not equal the operation could throw, because 2180 // we might need to allocate a new map for __x after moving from it 2181 // or we might need to allocate new elements for *this. 2182 void 2183 _M_move_assign1(deque&& __x, /* always equal: */ false_type) 2184 { 2185 constexpr bool __move_storage = 2186 _Alloc_traits::_S_propagate_on_move_assign(); 2187 _M_move_assign2(std::move(__x), __bool_constant<__move_storage>()); 2188 } 2189 2190 // Destroy all elements and deallocate all memory, then replace 2191 // with elements created from __args. 2192 template<typename... _Args> 2193 void 2194 _M_replace_map(_Args&&... __args) 2195 { 2196 // Create new data first, so if allocation fails there are no effects. 2197 deque __newobj(std::forward<_Args>(__args)...); 2198 // Free existing storage using existing allocator. 2199 clear(); 2200 _M_deallocate_node(*begin()._M_node); // one node left after clear() 2201 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 2202 this->_M_impl._M_map = nullptr; 2203 this->_M_impl._M_map_size = 0; 2204 // Take ownership of replacement memory. 2205 this->_M_impl._M_swap_data(__newobj._M_impl); 2206 } 2207 2208 // Do move assignment when the allocator propagates. 2209 void 2210 _M_move_assign2(deque&& __x, /* propagate: */ true_type) 2211 { 2212 // Make a copy of the original allocator state. 2213 auto __alloc = __x._M_get_Tp_allocator(); 2214 // The allocator propagates so storage can be moved from __x, 2215 // leaving __x in a valid empty state with a moved-from allocator. 2216 _M_replace_map(std::move(__x)); 2217 // Move the corresponding allocator state too. 2218 _M_get_Tp_allocator() = std::move(__alloc); 2219 } 2220 2221 // Do move assignment when it may not be possible to move source 2222 // object's memory, resulting in a linear-time operation. 2223 void 2224 _M_move_assign2(deque&& __x, /* propagate: */ false_type) 2225 { 2226 if (__x._M_get_Tp_allocator() == this->_M_get_Tp_allocator()) 2227 { 2228 // The allocators are equal so storage can be moved from __x, 2229 // leaving __x in a valid empty state with its current allocator. 2230 _M_replace_map(std::move(__x), __x.get_allocator()); 2231 } 2232 else 2233 { 2234 // The rvalue's allocator cannot be moved and is not equal, 2235 // so we need to individually move each element. 2236 _M_assign_aux(std::__make_move_if_noexcept_iterator(__x.begin()), 2237 std::__make_move_if_noexcept_iterator(__x.end()), 2238 std::random_access_iterator_tag()); 2239 __x.clear(); 2240 } 2241 } 2242 #endif 2243 }; 2244 2245 2246 /** 2247 * @brief Deque equality comparison. 2248 * @param __x A %deque. 2249 * @param __y A %deque of the same type as @a __x. 2250 * @return True iff the size and elements of the deques are equal. 2251 * 2252 * This is an equivalence relation. It is linear in the size of the 2253 * deques. Deques are considered equivalent if their sizes are equal, 2254 * and if corresponding elements compare equal. 2255 */ 2256 template<typename _Tp, typename _Alloc> 2257 inline bool 2258 operator==(const deque<_Tp, _Alloc>& __x, 2259 const deque<_Tp, _Alloc>& __y) 2260 { return __x.size() == __y.size() 2261 && std::equal(__x.begin(), __x.end(), __y.begin()); } 2262 2263 /** 2264 * @brief Deque ordering relation. 2265 * @param __x A %deque. 2266 * @param __y A %deque of the same type as @a __x. 2267 * @return True iff @a x is lexicographically less than @a __y. 2268 * 2269 * This is a total ordering relation. It is linear in the size of the 2270 * deques. The elements must be comparable with @c <. 2271 * 2272 * See std::lexicographical_compare() for how the determination is made. 2273 */ 2274 template<typename _Tp, typename _Alloc> 2275 inline bool 2276 operator<(const deque<_Tp, _Alloc>& __x, 2277 const deque<_Tp, _Alloc>& __y) 2278 { return std::lexicographical_compare(__x.begin(), __x.end(), 2279 __y.begin(), __y.end()); } 2280 2281 /// Based on operator== 2282 template<typename _Tp, typename _Alloc> 2283 inline bool 2284 operator!=(const deque<_Tp, _Alloc>& __x, 2285 const deque<_Tp, _Alloc>& __y) 2286 { return !(__x == __y); } 2287 2288 /// Based on operator< 2289 template<typename _Tp, typename _Alloc> 2290 inline bool 2291 operator>(const deque<_Tp, _Alloc>& __x, 2292 const deque<_Tp, _Alloc>& __y) 2293 { return __y < __x; } 2294 2295 /// Based on operator< 2296 template<typename _Tp, typename _Alloc> 2297 inline bool 2298 operator<=(const deque<_Tp, _Alloc>& __x, 2299 const deque<_Tp, _Alloc>& __y) 2300 { return !(__y < __x); } 2301 2302 /// Based on operator< 2303 template<typename _Tp, typename _Alloc> 2304 inline bool 2305 operator>=(const deque<_Tp, _Alloc>& __x, 2306 const deque<_Tp, _Alloc>& __y) 2307 { return !(__x < __y); } 2308 2309 /// See std::deque::swap(). 2310 template<typename _Tp, typename _Alloc> 2311 inline void 2312 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y) 2313 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y))) 2314 { __x.swap(__y); } 2315 2316 #undef _GLIBCXX_DEQUE_BUF_SIZE 2317 2318 _GLIBCXX_END_NAMESPACE_CONTAINER 2319 } // namespace std 2320 2321 #endif /* _STL_DEQUE_H */ 2322