1 // Deque implementation -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /* 27 * 28 * Copyright (c) 1994 29 * Hewlett-Packard Company 30 * 31 * Permission to use, copy, modify, distribute and sell this software 32 * and its documentation for any purpose is hereby granted without fee, 33 * provided that the above copyright notice appear in all copies and 34 * that both that copyright notice and this permission notice appear 35 * in supporting documentation. Hewlett-Packard Company makes no 36 * representations about the suitability of this software for any 37 * purpose. It is provided "as is" without express or implied warranty. 38 * 39 * 40 * Copyright (c) 1997 41 * Silicon Graphics Computer Systems, Inc. 42 * 43 * Permission to use, copy, modify, distribute and sell this software 44 * and its documentation for any purpose is hereby granted without fee, 45 * provided that the above copyright notice appear in all copies and 46 * that both that copyright notice and this permission notice appear 47 * in supporting documentation. Silicon Graphics makes no 48 * representations about the suitability of this software for any 49 * purpose. It is provided "as is" without express or implied warranty. 50 */ 51 52 /** @file stl_deque.h 53 * This is an internal header file, included by other library headers. 54 * You should not attempt to use it directly. 55 */ 56 57 #ifndef _STL_DEQUE_H 58 #define _STL_DEQUE_H 1 59 60 #include <bits/concept_check.h> 61 #include <bits/stl_iterator_base_types.h> 62 #include <bits/stl_iterator_base_funcs.h> 63 #include <initializer_list> 64 65 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_D) 66 67 /** 68 * @brief This function controls the size of memory nodes. 69 * @param size The size of an element. 70 * @return The number (not byte size) of elements per node. 71 * 72 * This function started off as a compiler kludge from SGI, but seems to 73 * be a useful wrapper around a repeated constant expression. The '512' is 74 * tunable (and no other code needs to change), but no investigation has 75 * been done since inheriting the SGI code. 76 */ 77 inline size_t 78 __deque_buf_size(size_t __size) 79 { return __size < 512 ? size_t(512 / __size) : size_t(1); } 80 81 82 /** 83 * @brief A deque::iterator. 84 * 85 * Quite a bit of intelligence here. Much of the functionality of 86 * deque is actually passed off to this class. A deque holds two 87 * of these internally, marking its valid range. Access to 88 * elements is done as offsets of either of those two, relying on 89 * operator overloading in this class. 90 * 91 * All the functions are op overloads except for _M_set_node. 92 */ 93 template<typename _Tp, typename _Ref, typename _Ptr> 94 struct _Deque_iterator 95 { 96 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator; 97 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator; 98 99 static size_t _S_buffer_size() 100 { return __deque_buf_size(sizeof(_Tp)); } 101 102 typedef std::random_access_iterator_tag iterator_category; 103 typedef _Tp value_type; 104 typedef _Ptr pointer; 105 typedef _Ref reference; 106 typedef size_t size_type; 107 typedef ptrdiff_t difference_type; 108 typedef _Tp** _Map_pointer; 109 typedef _Deque_iterator _Self; 110 111 _Tp* _M_cur; 112 _Tp* _M_first; 113 _Tp* _M_last; 114 _Map_pointer _M_node; 115 116 _Deque_iterator(_Tp* __x, _Map_pointer __y) 117 : _M_cur(__x), _M_first(*__y), 118 _M_last(*__y + _S_buffer_size()), _M_node(__y) { } 119 120 _Deque_iterator() 121 : _M_cur(0), _M_first(0), _M_last(0), _M_node(0) { } 122 123 _Deque_iterator(const iterator& __x) 124 : _M_cur(__x._M_cur), _M_first(__x._M_first), 125 _M_last(__x._M_last), _M_node(__x._M_node) { } 126 127 reference 128 operator*() const 129 { return *_M_cur; } 130 131 pointer 132 operator->() const 133 { return _M_cur; } 134 135 _Self& 136 operator++() 137 { 138 ++_M_cur; 139 if (_M_cur == _M_last) 140 { 141 _M_set_node(_M_node + 1); 142 _M_cur = _M_first; 143 } 144 return *this; 145 } 146 147 _Self 148 operator++(int) 149 { 150 _Self __tmp = *this; 151 ++*this; 152 return __tmp; 153 } 154 155 _Self& 156 operator--() 157 { 158 if (_M_cur == _M_first) 159 { 160 _M_set_node(_M_node - 1); 161 _M_cur = _M_last; 162 } 163 --_M_cur; 164 return *this; 165 } 166 167 _Self 168 operator--(int) 169 { 170 _Self __tmp = *this; 171 --*this; 172 return __tmp; 173 } 174 175 _Self& 176 operator+=(difference_type __n) 177 { 178 const difference_type __offset = __n + (_M_cur - _M_first); 179 if (__offset >= 0 && __offset < difference_type(_S_buffer_size())) 180 _M_cur += __n; 181 else 182 { 183 const difference_type __node_offset = 184 __offset > 0 ? __offset / difference_type(_S_buffer_size()) 185 : -difference_type((-__offset - 1) 186 / _S_buffer_size()) - 1; 187 _M_set_node(_M_node + __node_offset); 188 _M_cur = _M_first + (__offset - __node_offset 189 * difference_type(_S_buffer_size())); 190 } 191 return *this; 192 } 193 194 _Self 195 operator+(difference_type __n) const 196 { 197 _Self __tmp = *this; 198 return __tmp += __n; 199 } 200 201 _Self& 202 operator-=(difference_type __n) 203 { return *this += -__n; } 204 205 _Self 206 operator-(difference_type __n) const 207 { 208 _Self __tmp = *this; 209 return __tmp -= __n; 210 } 211 212 reference 213 operator[](difference_type __n) const 214 { return *(*this + __n); } 215 216 /** 217 * Prepares to traverse new_node. Sets everything except 218 * _M_cur, which should therefore be set by the caller 219 * immediately afterwards, based on _M_first and _M_last. 220 */ 221 void 222 _M_set_node(_Map_pointer __new_node) 223 { 224 _M_node = __new_node; 225 _M_first = *__new_node; 226 _M_last = _M_first + difference_type(_S_buffer_size()); 227 } 228 }; 229 230 // Note: we also provide overloads whose operands are of the same type in 231 // order to avoid ambiguous overload resolution when std::rel_ops operators 232 // are in scope (for additional details, see libstdc++/3628) 233 template<typename _Tp, typename _Ref, typename _Ptr> 234 inline bool 235 operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 236 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 237 { return __x._M_cur == __y._M_cur; } 238 239 template<typename _Tp, typename _RefL, typename _PtrL, 240 typename _RefR, typename _PtrR> 241 inline bool 242 operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 243 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 244 { return __x._M_cur == __y._M_cur; } 245 246 template<typename _Tp, typename _Ref, typename _Ptr> 247 inline bool 248 operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 249 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 250 { return !(__x == __y); } 251 252 template<typename _Tp, typename _RefL, typename _PtrL, 253 typename _RefR, typename _PtrR> 254 inline bool 255 operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 256 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 257 { return !(__x == __y); } 258 259 template<typename _Tp, typename _Ref, typename _Ptr> 260 inline bool 261 operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 262 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 263 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 264 : (__x._M_node < __y._M_node); } 265 266 template<typename _Tp, typename _RefL, typename _PtrL, 267 typename _RefR, typename _PtrR> 268 inline bool 269 operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 270 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 271 { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur) 272 : (__x._M_node < __y._M_node); } 273 274 template<typename _Tp, typename _Ref, typename _Ptr> 275 inline bool 276 operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 277 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 278 { return __y < __x; } 279 280 template<typename _Tp, typename _RefL, typename _PtrL, 281 typename _RefR, typename _PtrR> 282 inline bool 283 operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 284 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 285 { return __y < __x; } 286 287 template<typename _Tp, typename _Ref, typename _Ptr> 288 inline bool 289 operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 290 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 291 { return !(__y < __x); } 292 293 template<typename _Tp, typename _RefL, typename _PtrL, 294 typename _RefR, typename _PtrR> 295 inline bool 296 operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 297 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 298 { return !(__y < __x); } 299 300 template<typename _Tp, typename _Ref, typename _Ptr> 301 inline bool 302 operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 303 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 304 { return !(__x < __y); } 305 306 template<typename _Tp, typename _RefL, typename _PtrL, 307 typename _RefR, typename _PtrR> 308 inline bool 309 operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 310 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 311 { return !(__x < __y); } 312 313 // _GLIBCXX_RESOLVE_LIB_DEFECTS 314 // According to the resolution of DR179 not only the various comparison 315 // operators but also operator- must accept mixed iterator/const_iterator 316 // parameters. 317 template<typename _Tp, typename _Ref, typename _Ptr> 318 inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 319 operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x, 320 const _Deque_iterator<_Tp, _Ref, _Ptr>& __y) 321 { 322 return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type 323 (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size()) 324 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 325 + (__y._M_last - __y._M_cur); 326 } 327 328 template<typename _Tp, typename _RefL, typename _PtrL, 329 typename _RefR, typename _PtrR> 330 inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 331 operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x, 332 const _Deque_iterator<_Tp, _RefR, _PtrR>& __y) 333 { 334 return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type 335 (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size()) 336 * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first) 337 + (__y._M_last - __y._M_cur); 338 } 339 340 template<typename _Tp, typename _Ref, typename _Ptr> 341 inline _Deque_iterator<_Tp, _Ref, _Ptr> 342 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x) 343 { return __x + __n; } 344 345 template<typename _Tp> 346 void 347 fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>& __first, 348 const _Deque_iterator<_Tp, _Tp&, _Tp*>& __last, const _Tp& __value); 349 350 /** 351 * Deque base class. This class provides the unified face for %deque's 352 * allocation. This class's constructor and destructor allocate and 353 * deallocate (but do not initialize) storage. This makes %exception 354 * safety easier. 355 * 356 * Nothing in this class ever constructs or destroys an actual Tp element. 357 * (Deque handles that itself.) Only/All memory management is performed 358 * here. 359 */ 360 template<typename _Tp, typename _Alloc> 361 class _Deque_base 362 { 363 public: 364 typedef _Alloc allocator_type; 365 366 allocator_type 367 get_allocator() const 368 { return allocator_type(_M_get_Tp_allocator()); } 369 370 typedef _Deque_iterator<_Tp, _Tp&, _Tp*> iterator; 371 typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator; 372 373 _Deque_base() 374 : _M_impl() 375 { _M_initialize_map(0); } 376 377 _Deque_base(const allocator_type& __a, size_t __num_elements) 378 : _M_impl(__a) 379 { _M_initialize_map(__num_elements); } 380 381 _Deque_base(const allocator_type& __a) 382 : _M_impl(__a) 383 { } 384 385 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 386 _Deque_base(_Deque_base&& __x) 387 : _M_impl(__x._M_get_Tp_allocator()) 388 { 389 _M_initialize_map(0); 390 if (__x._M_impl._M_map) 391 { 392 std::swap(this->_M_impl._M_start, __x._M_impl._M_start); 393 std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish); 394 std::swap(this->_M_impl._M_map, __x._M_impl._M_map); 395 std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size); 396 } 397 } 398 #endif 399 400 ~_Deque_base(); 401 402 protected: 403 //This struct encapsulates the implementation of the std::deque 404 //standard container and at the same time makes use of the EBO 405 //for empty allocators. 406 typedef typename _Alloc::template rebind<_Tp*>::other _Map_alloc_type; 407 408 typedef typename _Alloc::template rebind<_Tp>::other _Tp_alloc_type; 409 410 struct _Deque_impl 411 : public _Tp_alloc_type 412 { 413 _Tp** _M_map; 414 size_t _M_map_size; 415 iterator _M_start; 416 iterator _M_finish; 417 418 _Deque_impl() 419 : _Tp_alloc_type(), _M_map(0), _M_map_size(0), 420 _M_start(), _M_finish() 421 { } 422 423 _Deque_impl(const _Tp_alloc_type& __a) 424 : _Tp_alloc_type(__a), _M_map(0), _M_map_size(0), 425 _M_start(), _M_finish() 426 { } 427 }; 428 429 _Tp_alloc_type& 430 _M_get_Tp_allocator() 431 { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); } 432 433 const _Tp_alloc_type& 434 _M_get_Tp_allocator() const 435 { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); } 436 437 _Map_alloc_type 438 _M_get_map_allocator() const 439 { return _Map_alloc_type(_M_get_Tp_allocator()); } 440 441 _Tp* 442 _M_allocate_node() 443 { 444 return _M_impl._Tp_alloc_type::allocate(__deque_buf_size(sizeof(_Tp))); 445 } 446 447 void 448 _M_deallocate_node(_Tp* __p) 449 { 450 _M_impl._Tp_alloc_type::deallocate(__p, __deque_buf_size(sizeof(_Tp))); 451 } 452 453 _Tp** 454 _M_allocate_map(size_t __n) 455 { return _M_get_map_allocator().allocate(__n); } 456 457 void 458 _M_deallocate_map(_Tp** __p, size_t __n) 459 { _M_get_map_allocator().deallocate(__p, __n); } 460 461 protected: 462 void _M_initialize_map(size_t); 463 void _M_create_nodes(_Tp** __nstart, _Tp** __nfinish); 464 void _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish); 465 enum { _S_initial_map_size = 8 }; 466 467 _Deque_impl _M_impl; 468 }; 469 470 template<typename _Tp, typename _Alloc> 471 _Deque_base<_Tp, _Alloc>:: 472 ~_Deque_base() 473 { 474 if (this->_M_impl._M_map) 475 { 476 _M_destroy_nodes(this->_M_impl._M_start._M_node, 477 this->_M_impl._M_finish._M_node + 1); 478 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 479 } 480 } 481 482 /** 483 * @brief Layout storage. 484 * @param num_elements The count of T's for which to allocate space 485 * at first. 486 * @return Nothing. 487 * 488 * The initial underlying memory layout is a bit complicated... 489 */ 490 template<typename _Tp, typename _Alloc> 491 void 492 _Deque_base<_Tp, _Alloc>:: 493 _M_initialize_map(size_t __num_elements) 494 { 495 const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp)) 496 + 1); 497 498 this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size, 499 size_t(__num_nodes + 2)); 500 this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size); 501 502 // For "small" maps (needing less than _M_map_size nodes), allocation 503 // starts in the middle elements and grows outwards. So nstart may be 504 // the beginning of _M_map, but for small maps it may be as far in as 505 // _M_map+3. 506 507 _Tp** __nstart = (this->_M_impl._M_map 508 + (this->_M_impl._M_map_size - __num_nodes) / 2); 509 _Tp** __nfinish = __nstart + __num_nodes; 510 511 __try 512 { _M_create_nodes(__nstart, __nfinish); } 513 __catch(...) 514 { 515 _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size); 516 this->_M_impl._M_map = 0; 517 this->_M_impl._M_map_size = 0; 518 __throw_exception_again; 519 } 520 521 this->_M_impl._M_start._M_set_node(__nstart); 522 this->_M_impl._M_finish._M_set_node(__nfinish - 1); 523 this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first; 524 this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first 525 + __num_elements 526 % __deque_buf_size(sizeof(_Tp))); 527 } 528 529 template<typename _Tp, typename _Alloc> 530 void 531 _Deque_base<_Tp, _Alloc>:: 532 _M_create_nodes(_Tp** __nstart, _Tp** __nfinish) 533 { 534 _Tp** __cur; 535 __try 536 { 537 for (__cur = __nstart; __cur < __nfinish; ++__cur) 538 *__cur = this->_M_allocate_node(); 539 } 540 __catch(...) 541 { 542 _M_destroy_nodes(__nstart, __cur); 543 __throw_exception_again; 544 } 545 } 546 547 template<typename _Tp, typename _Alloc> 548 void 549 _Deque_base<_Tp, _Alloc>:: 550 _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish) 551 { 552 for (_Tp** __n = __nstart; __n < __nfinish; ++__n) 553 _M_deallocate_node(*__n); 554 } 555 556 /** 557 * @brief A standard container using fixed-size memory allocation and 558 * constant-time manipulation of elements at either end. 559 * 560 * @ingroup sequences 561 * 562 * Meets the requirements of a <a href="tables.html#65">container</a>, a 563 * <a href="tables.html#66">reversible container</a>, and a 564 * <a href="tables.html#67">sequence</a>, including the 565 * <a href="tables.html#68">optional sequence requirements</a>. 566 * 567 * In previous HP/SGI versions of deque, there was an extra template 568 * parameter so users could control the node size. This extension turned 569 * out to violate the C++ standard (it can be detected using template 570 * template parameters), and it was removed. 571 * 572 * Here's how a deque<Tp> manages memory. Each deque has 4 members: 573 * 574 * - Tp** _M_map 575 * - size_t _M_map_size 576 * - iterator _M_start, _M_finish 577 * 578 * map_size is at least 8. %map is an array of map_size 579 * pointers-to-"nodes". (The name %map has nothing to do with the 580 * std::map class, and "nodes" should not be confused with 581 * std::list's usage of "node".) 582 * 583 * A "node" has no specific type name as such, but it is referred 584 * to as "node" in this file. It is a simple array-of-Tp. If Tp 585 * is very large, there will be one Tp element per node (i.e., an 586 * "array" of one). For non-huge Tp's, node size is inversely 587 * related to Tp size: the larger the Tp, the fewer Tp's will fit 588 * in a node. The goal here is to keep the total size of a node 589 * relatively small and constant over different Tp's, to improve 590 * allocator efficiency. 591 * 592 * Not every pointer in the %map array will point to a node. If 593 * the initial number of elements in the deque is small, the 594 * /middle/ %map pointers will be valid, and the ones at the edges 595 * will be unused. This same situation will arise as the %map 596 * grows: available %map pointers, if any, will be on the ends. As 597 * new nodes are created, only a subset of the %map's pointers need 598 * to be copied "outward". 599 * 600 * Class invariants: 601 * - For any nonsingular iterator i: 602 * - i.node points to a member of the %map array. (Yes, you read that 603 * correctly: i.node does not actually point to a node.) The member of 604 * the %map array is what actually points to the node. 605 * - i.first == *(i.node) (This points to the node (first Tp element).) 606 * - i.last == i.first + node_size 607 * - i.cur is a pointer in the range [i.first, i.last). NOTE: 608 * the implication of this is that i.cur is always a dereferenceable 609 * pointer, even if i is a past-the-end iterator. 610 * - Start and Finish are always nonsingular iterators. NOTE: this 611 * means that an empty deque must have one node, a deque with <N 612 * elements (where N is the node buffer size) must have one node, a 613 * deque with N through (2N-1) elements must have two nodes, etc. 614 * - For every node other than start.node and finish.node, every 615 * element in the node is an initialized object. If start.node == 616 * finish.node, then [start.cur, finish.cur) are initialized 617 * objects, and the elements outside that range are uninitialized 618 * storage. Otherwise, [start.cur, start.last) and [finish.first, 619 * finish.cur) are initialized objects, and [start.first, start.cur) 620 * and [finish.cur, finish.last) are uninitialized storage. 621 * - [%map, %map + map_size) is a valid, non-empty range. 622 * - [start.node, finish.node] is a valid range contained within 623 * [%map, %map + map_size). 624 * - A pointer in the range [%map, %map + map_size) points to an allocated 625 * node if and only if the pointer is in the range 626 * [start.node, finish.node]. 627 * 628 * Here's the magic: nothing in deque is "aware" of the discontiguous 629 * storage! 630 * 631 * The memory setup and layout occurs in the parent, _Base, and the iterator 632 * class is entirely responsible for "leaping" from one node to the next. 633 * All the implementation routines for deque itself work only through the 634 * start and finish iterators. This keeps the routines simple and sane, 635 * and we can use other standard algorithms as well. 636 */ 637 template<typename _Tp, typename _Alloc = std::allocator<_Tp> > 638 class deque : protected _Deque_base<_Tp, _Alloc> 639 { 640 // concept requirements 641 typedef typename _Alloc::value_type _Alloc_value_type; 642 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 643 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept) 644 645 typedef _Deque_base<_Tp, _Alloc> _Base; 646 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type; 647 648 public: 649 typedef _Tp value_type; 650 typedef typename _Tp_alloc_type::pointer pointer; 651 typedef typename _Tp_alloc_type::const_pointer const_pointer; 652 typedef typename _Tp_alloc_type::reference reference; 653 typedef typename _Tp_alloc_type::const_reference const_reference; 654 typedef typename _Base::iterator iterator; 655 typedef typename _Base::const_iterator const_iterator; 656 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 657 typedef std::reverse_iterator<iterator> reverse_iterator; 658 typedef size_t size_type; 659 typedef ptrdiff_t difference_type; 660 typedef _Alloc allocator_type; 661 662 protected: 663 typedef pointer* _Map_pointer; 664 665 static size_t _S_buffer_size() 666 { return __deque_buf_size(sizeof(_Tp)); } 667 668 // Functions controlling memory layout, and nothing else. 669 using _Base::_M_initialize_map; 670 using _Base::_M_create_nodes; 671 using _Base::_M_destroy_nodes; 672 using _Base::_M_allocate_node; 673 using _Base::_M_deallocate_node; 674 using _Base::_M_allocate_map; 675 using _Base::_M_deallocate_map; 676 using _Base::_M_get_Tp_allocator; 677 678 /** 679 * A total of four data members accumulated down the hierarchy. 680 * May be accessed via _M_impl.* 681 */ 682 using _Base::_M_impl; 683 684 public: 685 // [23.2.1.1] construct/copy/destroy 686 // (assign() and get_allocator() are also listed in this section) 687 /** 688 * @brief Default constructor creates no elements. 689 */ 690 deque() 691 : _Base() { } 692 693 /** 694 * @brief Creates a %deque with no elements. 695 * @param a An allocator object. 696 */ 697 explicit 698 deque(const allocator_type& __a) 699 : _Base(__a, 0) { } 700 701 /** 702 * @brief Creates a %deque with copies of an exemplar element. 703 * @param n The number of elements to initially create. 704 * @param value An element to copy. 705 * @param a An allocator. 706 * 707 * This constructor fills the %deque with @a n copies of @a value. 708 */ 709 explicit 710 deque(size_type __n, const value_type& __value = value_type(), 711 const allocator_type& __a = allocator_type()) 712 : _Base(__a, __n) 713 { _M_fill_initialize(__value); } 714 715 /** 716 * @brief %Deque copy constructor. 717 * @param x A %deque of identical element and allocator types. 718 * 719 * The newly-created %deque uses a copy of the allocation object used 720 * by @a x. 721 */ 722 deque(const deque& __x) 723 : _Base(__x._M_get_Tp_allocator(), __x.size()) 724 { std::__uninitialized_copy_a(__x.begin(), __x.end(), 725 this->_M_impl._M_start, 726 _M_get_Tp_allocator()); } 727 728 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 729 /** 730 * @brief %Deque move constructor. 731 * @param x A %deque of identical element and allocator types. 732 * 733 * The newly-created %deque contains the exact contents of @a x. 734 * The contents of @a x are a valid, but unspecified %deque. 735 */ 736 deque(deque&& __x) 737 : _Base(std::forward<_Base>(__x)) { } 738 739 /** 740 * @brief Builds a %deque from an initializer list. 741 * @param l An initializer_list. 742 * @param a An allocator object. 743 * 744 * Create a %deque consisting of copies of the elements in the 745 * initializer_list @a l. 746 * 747 * This will call the element type's copy constructor N times 748 * (where N is l.size()) and do no memory reallocation. 749 */ 750 deque(initializer_list<value_type> __l, 751 const allocator_type& __a = allocator_type()) 752 : _Base(__a) 753 { 754 _M_range_initialize(__l.begin(), __l.end(), 755 random_access_iterator_tag()); 756 } 757 #endif 758 759 /** 760 * @brief Builds a %deque from a range. 761 * @param first An input iterator. 762 * @param last An input iterator. 763 * @param a An allocator object. 764 * 765 * Create a %deque consisting of copies of the elements from [first, 766 * last). 767 * 768 * If the iterators are forward, bidirectional, or random-access, then 769 * this will call the elements' copy constructor N times (where N is 770 * distance(first,last)) and do no memory reallocation. But if only 771 * input iterators are used, then this will do at most 2N calls to the 772 * copy constructor, and logN memory reallocations. 773 */ 774 template<typename _InputIterator> 775 deque(_InputIterator __first, _InputIterator __last, 776 const allocator_type& __a = allocator_type()) 777 : _Base(__a) 778 { 779 // Check whether it's an integral type. If so, it's not an iterator. 780 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 781 _M_initialize_dispatch(__first, __last, _Integral()); 782 } 783 784 /** 785 * The dtor only erases the elements, and note that if the elements 786 * themselves are pointers, the pointed-to memory is not touched in any 787 * way. Managing the pointer is the user's responsibility. 788 */ 789 ~deque() 790 { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); } 791 792 /** 793 * @brief %Deque assignment operator. 794 * @param x A %deque of identical element and allocator types. 795 * 796 * All the elements of @a x are copied, but unlike the copy constructor, 797 * the allocator object is not copied. 798 */ 799 deque& 800 operator=(const deque& __x); 801 802 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 803 /** 804 * @brief %Deque move assignment operator. 805 * @param x A %deque of identical element and allocator types. 806 * 807 * The contents of @a x are moved into this deque (without copying). 808 * @a x is a valid, but unspecified %deque. 809 */ 810 deque& 811 operator=(deque&& __x) 812 { 813 // NB: DR 675. 814 this->clear(); 815 this->swap(__x); 816 return *this; 817 } 818 819 /** 820 * @brief Assigns an initializer list to a %deque. 821 * @param l An initializer_list. 822 * 823 * This function fills a %deque with copies of the elements in the 824 * initializer_list @a l. 825 * 826 * Note that the assignment completely changes the %deque and that the 827 * resulting %deque's size is the same as the number of elements 828 * assigned. Old data may be lost. 829 */ 830 deque& 831 operator=(initializer_list<value_type> __l) 832 { 833 this->assign(__l.begin(), __l.end()); 834 return *this; 835 } 836 #endif 837 838 /** 839 * @brief Assigns a given value to a %deque. 840 * @param n Number of elements to be assigned. 841 * @param val Value to be assigned. 842 * 843 * This function fills a %deque with @a n copies of the given 844 * value. Note that the assignment completely changes the 845 * %deque and that the resulting %deque's size is the same as 846 * the number of elements assigned. Old data may be lost. 847 */ 848 void 849 assign(size_type __n, const value_type& __val) 850 { _M_fill_assign(__n, __val); } 851 852 /** 853 * @brief Assigns a range to a %deque. 854 * @param first An input iterator. 855 * @param last An input iterator. 856 * 857 * This function fills a %deque with copies of the elements in the 858 * range [first,last). 859 * 860 * Note that the assignment completely changes the %deque and that the 861 * resulting %deque's size is the same as the number of elements 862 * assigned. Old data may be lost. 863 */ 864 template<typename _InputIterator> 865 void 866 assign(_InputIterator __first, _InputIterator __last) 867 { 868 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 869 _M_assign_dispatch(__first, __last, _Integral()); 870 } 871 872 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 873 /** 874 * @brief Assigns an initializer list to a %deque. 875 * @param l An initializer_list. 876 * 877 * This function fills a %deque with copies of the elements in the 878 * initializer_list @a l. 879 * 880 * Note that the assignment completely changes the %deque and that the 881 * resulting %deque's size is the same as the number of elements 882 * assigned. Old data may be lost. 883 */ 884 void 885 assign(initializer_list<value_type> __l) 886 { this->assign(__l.begin(), __l.end()); } 887 #endif 888 889 /// Get a copy of the memory allocation object. 890 allocator_type 891 get_allocator() const 892 { return _Base::get_allocator(); } 893 894 // iterators 895 /** 896 * Returns a read/write iterator that points to the first element in the 897 * %deque. Iteration is done in ordinary element order. 898 */ 899 iterator 900 begin() 901 { return this->_M_impl._M_start; } 902 903 /** 904 * Returns a read-only (constant) iterator that points to the first 905 * element in the %deque. Iteration is done in ordinary element order. 906 */ 907 const_iterator 908 begin() const 909 { return this->_M_impl._M_start; } 910 911 /** 912 * Returns a read/write iterator that points one past the last 913 * element in the %deque. Iteration is done in ordinary 914 * element order. 915 */ 916 iterator 917 end() 918 { return this->_M_impl._M_finish; } 919 920 /** 921 * Returns a read-only (constant) iterator that points one past 922 * the last element in the %deque. Iteration is done in 923 * ordinary element order. 924 */ 925 const_iterator 926 end() const 927 { return this->_M_impl._M_finish; } 928 929 /** 930 * Returns a read/write reverse iterator that points to the 931 * last element in the %deque. Iteration is done in reverse 932 * element order. 933 */ 934 reverse_iterator 935 rbegin() 936 { return reverse_iterator(this->_M_impl._M_finish); } 937 938 /** 939 * Returns a read-only (constant) reverse iterator that points 940 * to the last element in the %deque. Iteration is done in 941 * reverse element order. 942 */ 943 const_reverse_iterator 944 rbegin() const 945 { return const_reverse_iterator(this->_M_impl._M_finish); } 946 947 /** 948 * Returns a read/write reverse iterator that points to one 949 * before the first element in the %deque. Iteration is done 950 * in reverse element order. 951 */ 952 reverse_iterator 953 rend() 954 { return reverse_iterator(this->_M_impl._M_start); } 955 956 /** 957 * Returns a read-only (constant) reverse iterator that points 958 * to one before the first element in the %deque. Iteration is 959 * done in reverse element order. 960 */ 961 const_reverse_iterator 962 rend() const 963 { return const_reverse_iterator(this->_M_impl._M_start); } 964 965 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 966 /** 967 * Returns a read-only (constant) iterator that points to the first 968 * element in the %deque. Iteration is done in ordinary element order. 969 */ 970 const_iterator 971 cbegin() const 972 { return this->_M_impl._M_start; } 973 974 /** 975 * Returns a read-only (constant) iterator that points one past 976 * the last element in the %deque. Iteration is done in 977 * ordinary element order. 978 */ 979 const_iterator 980 cend() const 981 { return this->_M_impl._M_finish; } 982 983 /** 984 * Returns a read-only (constant) reverse iterator that points 985 * to the last element in the %deque. Iteration is done in 986 * reverse element order. 987 */ 988 const_reverse_iterator 989 crbegin() const 990 { return const_reverse_iterator(this->_M_impl._M_finish); } 991 992 /** 993 * Returns a read-only (constant) reverse iterator that points 994 * to one before the first element in the %deque. Iteration is 995 * done in reverse element order. 996 */ 997 const_reverse_iterator 998 crend() const 999 { return const_reverse_iterator(this->_M_impl._M_start); } 1000 #endif 1001 1002 // [23.2.1.2] capacity 1003 /** Returns the number of elements in the %deque. */ 1004 size_type 1005 size() const 1006 { return this->_M_impl._M_finish - this->_M_impl._M_start; } 1007 1008 /** Returns the size() of the largest possible %deque. */ 1009 size_type 1010 max_size() const 1011 { return _M_get_Tp_allocator().max_size(); } 1012 1013 /** 1014 * @brief Resizes the %deque to the specified number of elements. 1015 * @param new_size Number of elements the %deque should contain. 1016 * @param x Data with which new elements should be populated. 1017 * 1018 * This function will %resize the %deque to the specified 1019 * number of elements. If the number is smaller than the 1020 * %deque's current size the %deque is truncated, otherwise the 1021 * %deque is extended and new elements are populated with given 1022 * data. 1023 */ 1024 void 1025 resize(size_type __new_size, value_type __x = value_type()) 1026 { 1027 const size_type __len = size(); 1028 if (__new_size < __len) 1029 _M_erase_at_end(this->_M_impl._M_start + difference_type(__new_size)); 1030 else 1031 insert(this->_M_impl._M_finish, __new_size - __len, __x); 1032 } 1033 1034 /** 1035 * Returns true if the %deque is empty. (Thus begin() would 1036 * equal end().) 1037 */ 1038 bool 1039 empty() const 1040 { return this->_M_impl._M_finish == this->_M_impl._M_start; } 1041 1042 // element access 1043 /** 1044 * @brief Subscript access to the data contained in the %deque. 1045 * @param n The index of the element for which data should be 1046 * accessed. 1047 * @return Read/write reference to data. 1048 * 1049 * This operator allows for easy, array-style, data access. 1050 * Note that data access with this operator is unchecked and 1051 * out_of_range lookups are not defined. (For checked lookups 1052 * see at().) 1053 */ 1054 reference 1055 operator[](size_type __n) 1056 { return this->_M_impl._M_start[difference_type(__n)]; } 1057 1058 /** 1059 * @brief Subscript access to the data contained in the %deque. 1060 * @param n The index of the element for which data should be 1061 * accessed. 1062 * @return Read-only (constant) reference to data. 1063 * 1064 * This operator allows for easy, array-style, data access. 1065 * Note that data access with this operator is unchecked and 1066 * out_of_range lookups are not defined. (For checked lookups 1067 * see at().) 1068 */ 1069 const_reference 1070 operator[](size_type __n) const 1071 { return this->_M_impl._M_start[difference_type(__n)]; } 1072 1073 protected: 1074 /// Safety check used only from at(). 1075 void 1076 _M_range_check(size_type __n) const 1077 { 1078 if (__n >= this->size()) 1079 __throw_out_of_range(__N("deque::_M_range_check")); 1080 } 1081 1082 public: 1083 /** 1084 * @brief Provides access to the data contained in the %deque. 1085 * @param n The index of the element for which data should be 1086 * accessed. 1087 * @return Read/write reference to data. 1088 * @throw std::out_of_range If @a n is an invalid index. 1089 * 1090 * This function provides for safer data access. The parameter 1091 * is first checked that it is in the range of the deque. The 1092 * function throws out_of_range if the check fails. 1093 */ 1094 reference 1095 at(size_type __n) 1096 { 1097 _M_range_check(__n); 1098 return (*this)[__n]; 1099 } 1100 1101 /** 1102 * @brief Provides access to the data contained in the %deque. 1103 * @param n The index of the element for which data should be 1104 * accessed. 1105 * @return Read-only (constant) reference to data. 1106 * @throw std::out_of_range If @a n is an invalid index. 1107 * 1108 * This function provides for safer data access. The parameter is first 1109 * checked that it is in the range of the deque. The function throws 1110 * out_of_range if the check fails. 1111 */ 1112 const_reference 1113 at(size_type __n) const 1114 { 1115 _M_range_check(__n); 1116 return (*this)[__n]; 1117 } 1118 1119 /** 1120 * Returns a read/write reference to the data at the first 1121 * element of the %deque. 1122 */ 1123 reference 1124 front() 1125 { return *begin(); } 1126 1127 /** 1128 * Returns a read-only (constant) reference to the data at the first 1129 * element of the %deque. 1130 */ 1131 const_reference 1132 front() const 1133 { return *begin(); } 1134 1135 /** 1136 * Returns a read/write reference to the data at the last element of the 1137 * %deque. 1138 */ 1139 reference 1140 back() 1141 { 1142 iterator __tmp = end(); 1143 --__tmp; 1144 return *__tmp; 1145 } 1146 1147 /** 1148 * Returns a read-only (constant) reference to the data at the last 1149 * element of the %deque. 1150 */ 1151 const_reference 1152 back() const 1153 { 1154 const_iterator __tmp = end(); 1155 --__tmp; 1156 return *__tmp; 1157 } 1158 1159 // [23.2.1.2] modifiers 1160 /** 1161 * @brief Add data to the front of the %deque. 1162 * @param x Data to be added. 1163 * 1164 * This is a typical stack operation. The function creates an 1165 * element at the front of the %deque and assigns the given 1166 * data to it. Due to the nature of a %deque this operation 1167 * can be done in constant time. 1168 */ 1169 void 1170 push_front(const value_type& __x) 1171 { 1172 if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first) 1173 { 1174 this->_M_impl.construct(this->_M_impl._M_start._M_cur - 1, __x); 1175 --this->_M_impl._M_start._M_cur; 1176 } 1177 else 1178 _M_push_front_aux(__x); 1179 } 1180 1181 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1182 void 1183 push_front(value_type&& __x) 1184 { emplace_front(std::move(__x)); } 1185 1186 template<typename... _Args> 1187 void 1188 emplace_front(_Args&&... __args); 1189 #endif 1190 1191 /** 1192 * @brief Add data to the end of the %deque. 1193 * @param x Data to be added. 1194 * 1195 * This is a typical stack operation. The function creates an 1196 * element at the end of the %deque and assigns the given data 1197 * to it. Due to the nature of a %deque this operation can be 1198 * done in constant time. 1199 */ 1200 void 1201 push_back(const value_type& __x) 1202 { 1203 if (this->_M_impl._M_finish._M_cur 1204 != this->_M_impl._M_finish._M_last - 1) 1205 { 1206 this->_M_impl.construct(this->_M_impl._M_finish._M_cur, __x); 1207 ++this->_M_impl._M_finish._M_cur; 1208 } 1209 else 1210 _M_push_back_aux(__x); 1211 } 1212 1213 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1214 void 1215 push_back(value_type&& __x) 1216 { emplace_back(std::move(__x)); } 1217 1218 template<typename... _Args> 1219 void 1220 emplace_back(_Args&&... __args); 1221 #endif 1222 1223 /** 1224 * @brief Removes first element. 1225 * 1226 * This is a typical stack operation. It shrinks the %deque by one. 1227 * 1228 * Note that no data is returned, and if the first element's data is 1229 * needed, it should be retrieved before pop_front() is called. 1230 */ 1231 void 1232 pop_front() 1233 { 1234 if (this->_M_impl._M_start._M_cur 1235 != this->_M_impl._M_start._M_last - 1) 1236 { 1237 this->_M_impl.destroy(this->_M_impl._M_start._M_cur); 1238 ++this->_M_impl._M_start._M_cur; 1239 } 1240 else 1241 _M_pop_front_aux(); 1242 } 1243 1244 /** 1245 * @brief Removes last element. 1246 * 1247 * This is a typical stack operation. It shrinks the %deque by one. 1248 * 1249 * Note that no data is returned, and if the last element's data is 1250 * needed, it should be retrieved before pop_back() is called. 1251 */ 1252 void 1253 pop_back() 1254 { 1255 if (this->_M_impl._M_finish._M_cur 1256 != this->_M_impl._M_finish._M_first) 1257 { 1258 --this->_M_impl._M_finish._M_cur; 1259 this->_M_impl.destroy(this->_M_impl._M_finish._M_cur); 1260 } 1261 else 1262 _M_pop_back_aux(); 1263 } 1264 1265 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1266 /** 1267 * @brief Inserts an object in %deque before specified iterator. 1268 * @param position An iterator into the %deque. 1269 * @param args Arguments. 1270 * @return An iterator that points to the inserted data. 1271 * 1272 * This function will insert an object of type T constructed 1273 * with T(std::forward<Args>(args)...) before the specified location. 1274 */ 1275 template<typename... _Args> 1276 iterator 1277 emplace(iterator __position, _Args&&... __args); 1278 #endif 1279 1280 /** 1281 * @brief Inserts given value into %deque before specified iterator. 1282 * @param position An iterator into the %deque. 1283 * @param x Data to be inserted. 1284 * @return An iterator that points to the inserted data. 1285 * 1286 * This function will insert a copy of the given value before the 1287 * specified location. 1288 */ 1289 iterator 1290 insert(iterator __position, const value_type& __x); 1291 1292 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1293 /** 1294 * @brief Inserts given rvalue into %deque before specified iterator. 1295 * @param position An iterator into the %deque. 1296 * @param x Data to be inserted. 1297 * @return An iterator that points to the inserted data. 1298 * 1299 * This function will insert a copy of the given rvalue before the 1300 * specified location. 1301 */ 1302 iterator 1303 insert(iterator __position, value_type&& __x) 1304 { return emplace(__position, std::move(__x)); } 1305 1306 /** 1307 * @brief Inserts an initializer list into the %deque. 1308 * @param p An iterator into the %deque. 1309 * @param l An initializer_list. 1310 * 1311 * This function will insert copies of the data in the 1312 * initializer_list @a l into the %deque before the location 1313 * specified by @a p. This is known as "list insert." 1314 */ 1315 void 1316 insert(iterator __p, initializer_list<value_type> __l) 1317 { this->insert(__p, __l.begin(), __l.end()); } 1318 #endif 1319 1320 /** 1321 * @brief Inserts a number of copies of given data into the %deque. 1322 * @param position An iterator into the %deque. 1323 * @param n Number of elements to be inserted. 1324 * @param x Data to be inserted. 1325 * 1326 * This function will insert a specified number of copies of the given 1327 * data before the location specified by @a position. 1328 */ 1329 void 1330 insert(iterator __position, size_type __n, const value_type& __x) 1331 { _M_fill_insert(__position, __n, __x); } 1332 1333 /** 1334 * @brief Inserts a range into the %deque. 1335 * @param position An iterator into the %deque. 1336 * @param first An input iterator. 1337 * @param last An input iterator. 1338 * 1339 * This function will insert copies of the data in the range 1340 * [first,last) into the %deque before the location specified 1341 * by @a pos. This is known as "range insert." 1342 */ 1343 template<typename _InputIterator> 1344 void 1345 insert(iterator __position, _InputIterator __first, 1346 _InputIterator __last) 1347 { 1348 // Check whether it's an integral type. If so, it's not an iterator. 1349 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 1350 _M_insert_dispatch(__position, __first, __last, _Integral()); 1351 } 1352 1353 /** 1354 * @brief Remove element at given position. 1355 * @param position Iterator pointing to element to be erased. 1356 * @return An iterator pointing to the next element (or end()). 1357 * 1358 * This function will erase the element at the given position and thus 1359 * shorten the %deque by one. 1360 * 1361 * The user is cautioned that 1362 * this function only erases the element, and that if the element is 1363 * itself a pointer, the pointed-to memory is not touched in any way. 1364 * Managing the pointer is the user's responsibility. 1365 */ 1366 iterator 1367 erase(iterator __position); 1368 1369 /** 1370 * @brief Remove a range of elements. 1371 * @param first Iterator pointing to the first element to be erased. 1372 * @param last Iterator pointing to one past the last element to be 1373 * erased. 1374 * @return An iterator pointing to the element pointed to by @a last 1375 * prior to erasing (or end()). 1376 * 1377 * This function will erase the elements in the range [first,last) and 1378 * shorten the %deque accordingly. 1379 * 1380 * The user is cautioned that 1381 * this function only erases the elements, and that if the elements 1382 * themselves are pointers, the pointed-to memory is not touched in any 1383 * way. Managing the pointer is the user's responsibility. 1384 */ 1385 iterator 1386 erase(iterator __first, iterator __last); 1387 1388 /** 1389 * @brief Swaps data with another %deque. 1390 * @param x A %deque of the same element and allocator types. 1391 * 1392 * This exchanges the elements between two deques in constant time. 1393 * (Four pointers, so it should be quite fast.) 1394 * Note that the global std::swap() function is specialized such that 1395 * std::swap(d1,d2) will feed to this function. 1396 */ 1397 void 1398 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1399 swap(deque&& __x) 1400 #else 1401 swap(deque& __x) 1402 #endif 1403 { 1404 std::swap(this->_M_impl._M_start, __x._M_impl._M_start); 1405 std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish); 1406 std::swap(this->_M_impl._M_map, __x._M_impl._M_map); 1407 std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size); 1408 1409 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1410 // 431. Swapping containers with unequal allocators. 1411 std::__alloc_swap<_Tp_alloc_type>::_S_do_it(_M_get_Tp_allocator(), 1412 __x._M_get_Tp_allocator()); 1413 } 1414 1415 /** 1416 * Erases all the elements. Note that this function only erases the 1417 * elements, and that if the elements themselves are pointers, the 1418 * pointed-to memory is not touched in any way. Managing the pointer is 1419 * the user's responsibility. 1420 */ 1421 void 1422 clear() 1423 { _M_erase_at_end(begin()); } 1424 1425 protected: 1426 // Internal constructor functions follow. 1427 1428 // called by the range constructor to implement [23.1.1]/9 1429 1430 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1431 // 438. Ambiguity in the "do the right thing" clause 1432 template<typename _Integer> 1433 void 1434 _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type) 1435 { 1436 _M_initialize_map(static_cast<size_type>(__n)); 1437 _M_fill_initialize(__x); 1438 } 1439 1440 // called by the range constructor to implement [23.1.1]/9 1441 template<typename _InputIterator> 1442 void 1443 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last, 1444 __false_type) 1445 { 1446 typedef typename std::iterator_traits<_InputIterator>:: 1447 iterator_category _IterCategory; 1448 _M_range_initialize(__first, __last, _IterCategory()); 1449 } 1450 1451 // called by the second initialize_dispatch above 1452 //@{ 1453 /** 1454 * @brief Fills the deque with whatever is in [first,last). 1455 * @param first An input iterator. 1456 * @param last An input iterator. 1457 * @return Nothing. 1458 * 1459 * If the iterators are actually forward iterators (or better), then the 1460 * memory layout can be done all at once. Else we move forward using 1461 * push_back on each value from the iterator. 1462 */ 1463 template<typename _InputIterator> 1464 void 1465 _M_range_initialize(_InputIterator __first, _InputIterator __last, 1466 std::input_iterator_tag); 1467 1468 // called by the second initialize_dispatch above 1469 template<typename _ForwardIterator> 1470 void 1471 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last, 1472 std::forward_iterator_tag); 1473 //@} 1474 1475 /** 1476 * @brief Fills the %deque with copies of value. 1477 * @param value Initial value. 1478 * @return Nothing. 1479 * @pre _M_start and _M_finish have already been initialized, 1480 * but none of the %deque's elements have yet been constructed. 1481 * 1482 * This function is called only when the user provides an explicit size 1483 * (with or without an explicit exemplar value). 1484 */ 1485 void 1486 _M_fill_initialize(const value_type& __value); 1487 1488 // Internal assign functions follow. The *_aux functions do the actual 1489 // assignment work for the range versions. 1490 1491 // called by the range assign to implement [23.1.1]/9 1492 1493 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1494 // 438. Ambiguity in the "do the right thing" clause 1495 template<typename _Integer> 1496 void 1497 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) 1498 { _M_fill_assign(__n, __val); } 1499 1500 // called by the range assign to implement [23.1.1]/9 1501 template<typename _InputIterator> 1502 void 1503 _M_assign_dispatch(_InputIterator __first, _InputIterator __last, 1504 __false_type) 1505 { 1506 typedef typename std::iterator_traits<_InputIterator>:: 1507 iterator_category _IterCategory; 1508 _M_assign_aux(__first, __last, _IterCategory()); 1509 } 1510 1511 // called by the second assign_dispatch above 1512 template<typename _InputIterator> 1513 void 1514 _M_assign_aux(_InputIterator __first, _InputIterator __last, 1515 std::input_iterator_tag); 1516 1517 // called by the second assign_dispatch above 1518 template<typename _ForwardIterator> 1519 void 1520 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last, 1521 std::forward_iterator_tag) 1522 { 1523 const size_type __len = std::distance(__first, __last); 1524 if (__len > size()) 1525 { 1526 _ForwardIterator __mid = __first; 1527 std::advance(__mid, size()); 1528 std::copy(__first, __mid, begin()); 1529 insert(end(), __mid, __last); 1530 } 1531 else 1532 _M_erase_at_end(std::copy(__first, __last, begin())); 1533 } 1534 1535 // Called by assign(n,t), and the range assign when it turns out 1536 // to be the same thing. 1537 void 1538 _M_fill_assign(size_type __n, const value_type& __val) 1539 { 1540 if (__n > size()) 1541 { 1542 std::fill(begin(), end(), __val); 1543 insert(end(), __n - size(), __val); 1544 } 1545 else 1546 { 1547 _M_erase_at_end(begin() + difference_type(__n)); 1548 std::fill(begin(), end(), __val); 1549 } 1550 } 1551 1552 //@{ 1553 /// Helper functions for push_* and pop_*. 1554 #ifndef __GXX_EXPERIMENTAL_CXX0X__ 1555 void _M_push_back_aux(const value_type&); 1556 1557 void _M_push_front_aux(const value_type&); 1558 #else 1559 template<typename... _Args> 1560 void _M_push_back_aux(_Args&&... __args); 1561 1562 template<typename... _Args> 1563 void _M_push_front_aux(_Args&&... __args); 1564 #endif 1565 1566 void _M_pop_back_aux(); 1567 1568 void _M_pop_front_aux(); 1569 //@} 1570 1571 // Internal insert functions follow. The *_aux functions do the actual 1572 // insertion work when all shortcuts fail. 1573 1574 // called by the range insert to implement [23.1.1]/9 1575 1576 // _GLIBCXX_RESOLVE_LIB_DEFECTS 1577 // 438. Ambiguity in the "do the right thing" clause 1578 template<typename _Integer> 1579 void 1580 _M_insert_dispatch(iterator __pos, 1581 _Integer __n, _Integer __x, __true_type) 1582 { _M_fill_insert(__pos, __n, __x); } 1583 1584 // called by the range insert to implement [23.1.1]/9 1585 template<typename _InputIterator> 1586 void 1587 _M_insert_dispatch(iterator __pos, 1588 _InputIterator __first, _InputIterator __last, 1589 __false_type) 1590 { 1591 typedef typename std::iterator_traits<_InputIterator>:: 1592 iterator_category _IterCategory; 1593 _M_range_insert_aux(__pos, __first, __last, _IterCategory()); 1594 } 1595 1596 // called by the second insert_dispatch above 1597 template<typename _InputIterator> 1598 void 1599 _M_range_insert_aux(iterator __pos, _InputIterator __first, 1600 _InputIterator __last, std::input_iterator_tag); 1601 1602 // called by the second insert_dispatch above 1603 template<typename _ForwardIterator> 1604 void 1605 _M_range_insert_aux(iterator __pos, _ForwardIterator __first, 1606 _ForwardIterator __last, std::forward_iterator_tag); 1607 1608 // Called by insert(p,n,x), and the range insert when it turns out to be 1609 // the same thing. Can use fill functions in optimal situations, 1610 // otherwise passes off to insert_aux(p,n,x). 1611 void 1612 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x); 1613 1614 // called by insert(p,x) 1615 #ifndef __GXX_EXPERIMENTAL_CXX0X__ 1616 iterator 1617 _M_insert_aux(iterator __pos, const value_type& __x); 1618 #else 1619 template<typename... _Args> 1620 iterator 1621 _M_insert_aux(iterator __pos, _Args&&... __args); 1622 #endif 1623 1624 // called by insert(p,n,x) via fill_insert 1625 void 1626 _M_insert_aux(iterator __pos, size_type __n, const value_type& __x); 1627 1628 // called by range_insert_aux for forward iterators 1629 template<typename _ForwardIterator> 1630 void 1631 _M_insert_aux(iterator __pos, 1632 _ForwardIterator __first, _ForwardIterator __last, 1633 size_type __n); 1634 1635 1636 // Internal erase functions follow. 1637 1638 void 1639 _M_destroy_data_aux(iterator __first, iterator __last); 1640 1641 // Called by ~deque(). 1642 // NB: Doesn't deallocate the nodes. 1643 template<typename _Alloc1> 1644 void 1645 _M_destroy_data(iterator __first, iterator __last, const _Alloc1&) 1646 { _M_destroy_data_aux(__first, __last); } 1647 1648 void 1649 _M_destroy_data(iterator __first, iterator __last, 1650 const std::allocator<_Tp>&) 1651 { 1652 if (!__has_trivial_destructor(value_type)) 1653 _M_destroy_data_aux(__first, __last); 1654 } 1655 1656 // Called by erase(q1, q2). 1657 void 1658 _M_erase_at_begin(iterator __pos) 1659 { 1660 _M_destroy_data(begin(), __pos, _M_get_Tp_allocator()); 1661 _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node); 1662 this->_M_impl._M_start = __pos; 1663 } 1664 1665 // Called by erase(q1, q2), resize(), clear(), _M_assign_aux, 1666 // _M_fill_assign, operator=. 1667 void 1668 _M_erase_at_end(iterator __pos) 1669 { 1670 _M_destroy_data(__pos, end(), _M_get_Tp_allocator()); 1671 _M_destroy_nodes(__pos._M_node + 1, 1672 this->_M_impl._M_finish._M_node + 1); 1673 this->_M_impl._M_finish = __pos; 1674 } 1675 1676 //@{ 1677 /// Memory-handling helpers for the previous internal insert functions. 1678 iterator 1679 _M_reserve_elements_at_front(size_type __n) 1680 { 1681 const size_type __vacancies = this->_M_impl._M_start._M_cur 1682 - this->_M_impl._M_start._M_first; 1683 if (__n > __vacancies) 1684 _M_new_elements_at_front(__n - __vacancies); 1685 return this->_M_impl._M_start - difference_type(__n); 1686 } 1687 1688 iterator 1689 _M_reserve_elements_at_back(size_type __n) 1690 { 1691 const size_type __vacancies = (this->_M_impl._M_finish._M_last 1692 - this->_M_impl._M_finish._M_cur) - 1; 1693 if (__n > __vacancies) 1694 _M_new_elements_at_back(__n - __vacancies); 1695 return this->_M_impl._M_finish + difference_type(__n); 1696 } 1697 1698 void 1699 _M_new_elements_at_front(size_type __new_elements); 1700 1701 void 1702 _M_new_elements_at_back(size_type __new_elements); 1703 //@} 1704 1705 1706 //@{ 1707 /** 1708 * @brief Memory-handling helpers for the major %map. 1709 * 1710 * Makes sure the _M_map has space for new nodes. Does not 1711 * actually add the nodes. Can invalidate _M_map pointers. 1712 * (And consequently, %deque iterators.) 1713 */ 1714 void 1715 _M_reserve_map_at_back(size_type __nodes_to_add = 1) 1716 { 1717 if (__nodes_to_add + 1 > this->_M_impl._M_map_size 1718 - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map)) 1719 _M_reallocate_map(__nodes_to_add, false); 1720 } 1721 1722 void 1723 _M_reserve_map_at_front(size_type __nodes_to_add = 1) 1724 { 1725 if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node 1726 - this->_M_impl._M_map)) 1727 _M_reallocate_map(__nodes_to_add, true); 1728 } 1729 1730 void 1731 _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front); 1732 //@} 1733 }; 1734 1735 1736 /** 1737 * @brief Deque equality comparison. 1738 * @param x A %deque. 1739 * @param y A %deque of the same type as @a x. 1740 * @return True iff the size and elements of the deques are equal. 1741 * 1742 * This is an equivalence relation. It is linear in the size of the 1743 * deques. Deques are considered equivalent if their sizes are equal, 1744 * and if corresponding elements compare equal. 1745 */ 1746 template<typename _Tp, typename _Alloc> 1747 inline bool 1748 operator==(const deque<_Tp, _Alloc>& __x, 1749 const deque<_Tp, _Alloc>& __y) 1750 { return __x.size() == __y.size() 1751 && std::equal(__x.begin(), __x.end(), __y.begin()); } 1752 1753 /** 1754 * @brief Deque ordering relation. 1755 * @param x A %deque. 1756 * @param y A %deque of the same type as @a x. 1757 * @return True iff @a x is lexicographically less than @a y. 1758 * 1759 * This is a total ordering relation. It is linear in the size of the 1760 * deques. The elements must be comparable with @c <. 1761 * 1762 * See std::lexicographical_compare() for how the determination is made. 1763 */ 1764 template<typename _Tp, typename _Alloc> 1765 inline bool 1766 operator<(const deque<_Tp, _Alloc>& __x, 1767 const deque<_Tp, _Alloc>& __y) 1768 { return std::lexicographical_compare(__x.begin(), __x.end(), 1769 __y.begin(), __y.end()); } 1770 1771 /// Based on operator== 1772 template<typename _Tp, typename _Alloc> 1773 inline bool 1774 operator!=(const deque<_Tp, _Alloc>& __x, 1775 const deque<_Tp, _Alloc>& __y) 1776 { return !(__x == __y); } 1777 1778 /// Based on operator< 1779 template<typename _Tp, typename _Alloc> 1780 inline bool 1781 operator>(const deque<_Tp, _Alloc>& __x, 1782 const deque<_Tp, _Alloc>& __y) 1783 { return __y < __x; } 1784 1785 /// Based on operator< 1786 template<typename _Tp, typename _Alloc> 1787 inline bool 1788 operator<=(const deque<_Tp, _Alloc>& __x, 1789 const deque<_Tp, _Alloc>& __y) 1790 { return !(__y < __x); } 1791 1792 /// Based on operator< 1793 template<typename _Tp, typename _Alloc> 1794 inline bool 1795 operator>=(const deque<_Tp, _Alloc>& __x, 1796 const deque<_Tp, _Alloc>& __y) 1797 { return !(__x < __y); } 1798 1799 /// See std::deque::swap(). 1800 template<typename _Tp, typename _Alloc> 1801 inline void 1802 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y) 1803 { __x.swap(__y); } 1804 1805 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 1806 template<typename _Tp, typename _Alloc> 1807 inline void 1808 swap(deque<_Tp,_Alloc>&& __x, deque<_Tp,_Alloc>& __y) 1809 { __x.swap(__y); } 1810 1811 template<typename _Tp, typename _Alloc> 1812 inline void 1813 swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>&& __y) 1814 { __x.swap(__y); } 1815 #endif 1816 1817 _GLIBCXX_END_NESTED_NAMESPACE 1818 1819 #endif /* _STL_DEQUE_H */ 1820
