1 // <scoped_allocator> -*- C++ -*- 2 3 // Copyright (C) 2011-2024 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 /** @file include/scoped_allocator 26 * This is a Standard C++ Library header. 27 */ 28 29 #ifndef _SCOPED_ALLOCATOR 30 #define _SCOPED_ALLOCATOR 1 31 32 #pragma GCC system_header 33 34 #if __cplusplus < 201103L 35 # include <bits/c++0x_warning.h> 36 #else 37 38 #include <tuple> 39 #include <bits/alloc_traits.h> 40 #include <bits/stl_pair.h> 41 #include <bits/uses_allocator.h> 42 #if __cplusplus > 201703L 43 # include <bits/uses_allocator_args.h> 44 #endif 45 46 #define __glibcxx_want_allocator_traits_is_always_equal 47 #include <bits/version.h> 48 49 namespace std _GLIBCXX_VISIBILITY(default) 50 { 51 _GLIBCXX_BEGIN_NAMESPACE_VERSION 52 53 /** 54 * @addtogroup allocators 55 * @{ 56 */ 57 58 template<typename _OuterAlloc, typename... _InnerAllocs> 59 class scoped_allocator_adaptor; 60 61 /// @cond undocumented 62 63 template<typename _Alloc> 64 using __outer_allocator_t 65 = decltype(std::declval<_Alloc>().outer_allocator()); 66 67 template<typename _Alloc, typename = void> 68 struct __outermost_type 69 { 70 using type = _Alloc; 71 static type& _S_outermost(_Alloc& __a) noexcept { return __a; } 72 }; 73 74 template<typename _Alloc> 75 struct __outermost_type<_Alloc, __void_t<__outer_allocator_t<_Alloc>>> 76 : __outermost_type< 77 typename remove_reference<__outer_allocator_t<_Alloc>>::type 78 > 79 { 80 using __base = __outermost_type< 81 typename remove_reference<__outer_allocator_t<_Alloc>>::type 82 >; 83 84 static typename __base::type& 85 _S_outermost(_Alloc& __a) noexcept 86 { return __base::_S_outermost(__a.outer_allocator()); } 87 }; 88 89 // Implementation of the OUTERMOST pseudofunction 90 template<typename _Alloc> 91 inline typename __outermost_type<_Alloc>::type& 92 __outermost(_Alloc& __a) 93 { return __outermost_type<_Alloc>::_S_outermost(__a); } 94 95 template<typename...> 96 struct __inner_type_impl; 97 98 template<typename _Outer> 99 struct __inner_type_impl<_Outer> 100 { 101 typedef scoped_allocator_adaptor<_Outer> __type; 102 103 __inner_type_impl() = default; 104 __inner_type_impl(const __inner_type_impl&) = default; 105 __inner_type_impl(__inner_type_impl&&) = default; 106 __inner_type_impl& operator=(const __inner_type_impl&) = default; 107 __inner_type_impl& operator=(__inner_type_impl&&) = default; 108 109 template<typename _Alloc> 110 __inner_type_impl(const __inner_type_impl<_Alloc>&) noexcept 111 { } 112 113 template<typename _Alloc> 114 __inner_type_impl(__inner_type_impl<_Alloc>&&) noexcept 115 { } 116 117 __type& 118 _M_get(__type* __p) noexcept { return *__p; } 119 120 const __type& 121 _M_get(const __type* __p) const noexcept { return *__p; } 122 123 tuple<> 124 _M_tie() const noexcept { return tuple<>(); } 125 126 bool 127 operator==(const __inner_type_impl&) const noexcept 128 { return true; } 129 }; 130 131 template<typename _Outer, typename _InnerHead, typename... _InnerTail> 132 struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...> 133 { 134 typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type; 135 136 __inner_type_impl() = default; 137 __inner_type_impl(const __inner_type_impl&) = default; 138 __inner_type_impl(__inner_type_impl&&) = default; 139 __inner_type_impl& operator=(const __inner_type_impl&) = default; 140 __inner_type_impl& operator=(__inner_type_impl&&) = default; 141 142 template<typename... _Allocs> 143 __inner_type_impl(const __inner_type_impl<_Allocs...>& __other) noexcept 144 : _M_inner(__other._M_inner) { } 145 146 template<typename... _Allocs> 147 __inner_type_impl(__inner_type_impl<_Allocs...>&& __other) noexcept 148 : _M_inner(std::move(__other._M_inner)) { } 149 150 template<typename... _Args> 151 explicit 152 __inner_type_impl(_Args&&... __args) noexcept 153 : _M_inner(std::forward<_Args>(__args)...) { } 154 155 __type& 156 _M_get(void*) noexcept { return _M_inner; } 157 158 const __type& 159 _M_get(const void*) const noexcept { return _M_inner; } 160 161 tuple<const _InnerHead&, const _InnerTail&...> 162 _M_tie() const noexcept 163 { return _M_inner._M_tie(); } 164 165 bool 166 operator==(const __inner_type_impl& __other) const noexcept 167 { return _M_inner == __other._M_inner; } 168 169 private: 170 template<typename...> friend struct __inner_type_impl; 171 template<typename, typename...> friend class scoped_allocator_adaptor; 172 173 __type _M_inner; 174 }; 175 176 /// @endcond 177 178 /// An adaptor to recursively pass an allocator to the objects it constructs 179 template<typename _OuterAlloc, typename... _InnerAllocs> 180 class scoped_allocator_adaptor 181 : public _OuterAlloc 182 { 183 typedef allocator_traits<_OuterAlloc> __traits; 184 185 typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type; 186 __inner_type _M_inner; 187 188 template<typename _Outer, typename... _Inner> 189 friend class scoped_allocator_adaptor; 190 191 template<typename...> 192 friend struct __inner_type_impl; 193 194 tuple<const _OuterAlloc&, const _InnerAllocs&...> 195 _M_tie() const noexcept 196 { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); } 197 198 template<typename _Alloc> 199 using __outermost_alloc_traits 200 = allocator_traits<typename __outermost_type<_Alloc>::type>; 201 202 #if ! __glibcxx_make_obj_using_allocator 203 template<typename _Tp, typename... _Args> 204 void 205 _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args) 206 { 207 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 208 _O_traits::construct(__outermost(*this), __p, 209 std::forward<_Args>(__args)...); 210 } 211 212 typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_; 213 typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_; 214 215 template<typename _Tp, typename... _Args> 216 void 217 _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args) 218 { 219 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 220 _O_traits::construct(__outermost(*this), __p, 221 allocator_arg, inner_allocator(), 222 std::forward<_Args>(__args)...); 223 } 224 225 template<typename _Tp, typename... _Args> 226 void 227 _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args) 228 { 229 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 230 _O_traits::construct(__outermost(*this), __p, 231 std::forward<_Args>(__args)..., 232 inner_allocator()); 233 } 234 #endif // ! make_obj_using_allocator 235 236 template<typename _Alloc> 237 static _Alloc 238 _S_select_on_copy(const _Alloc& __a) 239 { 240 typedef allocator_traits<_Alloc> __a_traits; 241 return __a_traits::select_on_container_copy_construction(__a); 242 } 243 244 template<std::size_t... _Indices> 245 scoped_allocator_adaptor(tuple<const _OuterAlloc&, 246 const _InnerAllocs&...> __refs, 247 _Index_tuple<_Indices...>) 248 : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))), 249 _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...) 250 { } 251 252 // Used to constrain constructors to disallow invalid conversions. 253 template<typename _Alloc> 254 using _Constructible = typename enable_if< 255 is_constructible<_OuterAlloc, _Alloc>::value 256 >::type; 257 258 // _GLIBCXX_RESOLVE_LIB_DEFECTS 259 // 2975. Missing case for pair construction in scoped [...] allocators 260 template<typename _Tp> 261 struct __not_pair { using type = void; }; 262 263 template<typename _Tp, typename _Up> 264 struct __not_pair<pair<_Tp, _Up>> { }; 265 266 public: 267 typedef _OuterAlloc outer_allocator_type; 268 typedef typename __inner_type::__type inner_allocator_type; 269 270 typedef typename __traits::value_type value_type; 271 typedef typename __traits::size_type size_type; 272 typedef typename __traits::difference_type difference_type; 273 typedef typename __traits::pointer pointer; 274 typedef typename __traits::const_pointer const_pointer; 275 typedef typename __traits::void_pointer void_pointer; 276 typedef typename __traits::const_void_pointer const_void_pointer; 277 278 typedef typename __or_< 279 typename __traits::propagate_on_container_copy_assignment, 280 typename allocator_traits<_InnerAllocs>:: 281 propagate_on_container_copy_assignment...>::type 282 propagate_on_container_copy_assignment; 283 284 typedef typename __or_< 285 typename __traits::propagate_on_container_move_assignment, 286 typename allocator_traits<_InnerAllocs>:: 287 propagate_on_container_move_assignment...>::type 288 propagate_on_container_move_assignment; 289 290 typedef typename __or_< 291 typename __traits::propagate_on_container_swap, 292 typename allocator_traits<_InnerAllocs>:: 293 propagate_on_container_swap...>::type 294 propagate_on_container_swap; 295 296 typedef typename __and_< 297 typename __traits::is_always_equal, 298 typename allocator_traits<_InnerAllocs>::is_always_equal...>::type 299 is_always_equal; 300 301 template <class _Tp> 302 struct rebind 303 { 304 typedef scoped_allocator_adaptor< 305 typename __traits::template rebind_alloc<_Tp>, 306 _InnerAllocs...> other; 307 }; 308 309 scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { } 310 311 template<typename _Outer2, typename = _Constructible<_Outer2>> 312 scoped_allocator_adaptor(_Outer2&& __outer, 313 const _InnerAllocs&... __inner) noexcept 314 : _OuterAlloc(std::forward<_Outer2>(__outer)), 315 _M_inner(__inner...) 316 { } 317 318 scoped_allocator_adaptor(const scoped_allocator_adaptor& __other) noexcept 319 : _OuterAlloc(__other.outer_allocator()), 320 _M_inner(__other._M_inner) 321 { } 322 323 scoped_allocator_adaptor(scoped_allocator_adaptor&& __other) noexcept 324 : _OuterAlloc(std::move(__other.outer_allocator())), 325 _M_inner(std::move(__other._M_inner)) 326 { } 327 328 template<typename _Outer2, typename = _Constructible<const _Outer2&>> 329 scoped_allocator_adaptor( 330 const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other 331 ) noexcept 332 : _OuterAlloc(__other.outer_allocator()), 333 _M_inner(__other._M_inner) 334 { } 335 336 template<typename _Outer2, typename = _Constructible<_Outer2>> 337 scoped_allocator_adaptor( 338 scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other) noexcept 339 : _OuterAlloc(std::move(__other.outer_allocator())), 340 _M_inner(std::move(__other._M_inner)) 341 { } 342 343 scoped_allocator_adaptor& 344 operator=(const scoped_allocator_adaptor&) = default; 345 346 scoped_allocator_adaptor& 347 operator=(scoped_allocator_adaptor&&) = default; 348 349 inner_allocator_type& 350 inner_allocator() noexcept 351 { return _M_inner._M_get(this); } 352 353 const inner_allocator_type& 354 inner_allocator() const noexcept 355 { return _M_inner._M_get(this); } 356 357 outer_allocator_type& 358 outer_allocator() noexcept 359 { return static_cast<_OuterAlloc&>(*this); } 360 361 const outer_allocator_type& 362 outer_allocator() const noexcept 363 { return static_cast<const _OuterAlloc&>(*this); } 364 365 _GLIBCXX_NODISCARD pointer 366 allocate(size_type __n) 367 { return __traits::allocate(outer_allocator(), __n); } 368 369 _GLIBCXX_NODISCARD pointer 370 allocate(size_type __n, const_void_pointer __hint) 371 { return __traits::allocate(outer_allocator(), __n, __hint); } 372 373 void deallocate(pointer __p, size_type __n) noexcept 374 { return __traits::deallocate(outer_allocator(), __p, __n); } 375 376 size_type max_size() const 377 { return __traits::max_size(outer_allocator()); } 378 379 #if ! __glibcxx_make_obj_using_allocator 380 template<typename _Tp, typename... _Args> 381 typename __not_pair<_Tp>::type 382 construct(_Tp* __p, _Args&&... __args) 383 { 384 auto& __inner = inner_allocator(); 385 auto __use_tag 386 = std::__use_alloc<_Tp, inner_allocator_type, _Args...>(__inner); 387 _M_construct(__use_tag, __p, std::forward<_Args>(__args)...); 388 } 389 390 template<typename _T1, typename _T2, typename... _Args1, 391 typename... _Args2> 392 void 393 construct(pair<_T1, _T2>* __p, piecewise_construct_t, 394 tuple<_Args1...> __x, tuple<_Args2...> __y) 395 { 396 // _GLIBCXX_RESOLVE_LIB_DEFECTS 397 // 2203. wrong argument types for piecewise construction 398 auto& __inner = inner_allocator(); 399 auto __x_use_tag 400 = std::__use_alloc<_T1, inner_allocator_type, _Args1...>(__inner); 401 auto __y_use_tag 402 = std::__use_alloc<_T2, inner_allocator_type, _Args2...>(__inner); 403 typename _Build_index_tuple<sizeof...(_Args1)>::__type __x_indices; 404 typename _Build_index_tuple<sizeof...(_Args2)>::__type __y_indices; 405 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 406 _O_traits::construct(__outermost(*this), __p, piecewise_construct, 407 _M_construct_p(__x_use_tag, __x_indices, __x), 408 _M_construct_p(__y_use_tag, __y_indices, __y)); 409 } 410 411 template<typename _T1, typename _T2> 412 void 413 construct(pair<_T1, _T2>* __p) 414 { construct(__p, piecewise_construct, tuple<>(), tuple<>()); } 415 416 template<typename _T1, typename _T2, typename _Up, typename _Vp> 417 void 418 construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v) 419 { 420 construct(__p, piecewise_construct, 421 std::forward_as_tuple(std::forward<_Up>(__u)), 422 std::forward_as_tuple(std::forward<_Vp>(__v))); 423 } 424 425 template<typename _T1, typename _T2, typename _Up, typename _Vp> 426 void 427 construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x) 428 { 429 construct(__p, piecewise_construct, 430 std::forward_as_tuple(__x.first), 431 std::forward_as_tuple(__x.second)); 432 } 433 434 template<typename _T1, typename _T2, typename _Up, typename _Vp> 435 void 436 construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x) 437 { 438 construct(__p, piecewise_construct, 439 std::forward_as_tuple(std::forward<_Up>(__x.first)), 440 std::forward_as_tuple(std::forward<_Vp>(__x.second))); 441 } 442 #else // make_obj_using_allocator 443 template<typename _Tp, typename... _Args> 444 __attribute__((__nonnull__)) 445 void 446 construct(_Tp* __p, _Args&&... __args) 447 { 448 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 449 std::apply([__p, this](auto&&... __newargs) { 450 _O_traits::construct(__outermost(*this), __p, 451 std::forward<decltype(__newargs)>(__newargs)...); 452 }, 453 uses_allocator_construction_args<_Tp>(inner_allocator(), 454 std::forward<_Args>(__args)...)); 455 } 456 #endif 457 458 template<typename _Tp> 459 void destroy(_Tp* __p) 460 { 461 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 462 _O_traits::destroy(__outermost(*this), __p); 463 } 464 465 scoped_allocator_adaptor 466 select_on_container_copy_construction() const 467 { 468 typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type 469 _Indices; 470 return scoped_allocator_adaptor(_M_tie(), _Indices()); 471 } 472 473 template <typename _OutA1, typename _OutA2, typename... _InA> 474 friend bool 475 operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 476 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept; 477 478 private: 479 #if ! __glibcxx_make_obj_using_allocator 480 template<typename _Ind, typename... _Args> 481 tuple<_Args&&...> 482 _M_construct_p(__uses_alloc0, _Ind, tuple<_Args...>& __t) 483 { return std::move(__t); } 484 485 template<size_t... _Ind, typename... _Args> 486 tuple<allocator_arg_t, inner_allocator_type&, _Args&&...> 487 _M_construct_p(__uses_alloc1_, _Index_tuple<_Ind...>, 488 tuple<_Args...>& __t) 489 { 490 return { allocator_arg, inner_allocator(), 491 std::get<_Ind>(std::move(__t))... 492 }; 493 } 494 495 template<size_t... _Ind, typename... _Args> 496 tuple<_Args&&..., inner_allocator_type&> 497 _M_construct_p(__uses_alloc2_, _Index_tuple<_Ind...>, 498 tuple<_Args...>& __t) 499 { 500 return { std::get<_Ind>(std::move(__t))..., inner_allocator() }; 501 } 502 #endif // ! make_obj_using_allocator 503 }; 504 505 /// @related std::scoped_allocator_adaptor 506 template <typename _OutA1, typename _OutA2, typename... _InA> 507 inline bool 508 operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 509 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept 510 { 511 return __a.outer_allocator() == __b.outer_allocator() 512 && __a._M_inner == __b._M_inner; 513 } 514 515 #if __cpp_impl_three_way_comparison < 201907L 516 /// @related std::scoped_allocator_adaptor 517 template <typename _OutA1, typename _OutA2, typename... _InA> 518 inline bool 519 operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 520 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept 521 { return !(__a == __b); } 522 #endif 523 524 /// @} 525 526 _GLIBCXX_END_NAMESPACE_VERSION 527 } // namespace 528 529 #endif // C++11 530 531 #endif // _SCOPED_ALLOCATOR 532
Indexes created Thu Jun 18 00:24:58 UTC 2026