1 // <scoped_allocator> -*- C++ -*- 2 3 // Copyright (C) 2011-2022 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 namespace std _GLIBCXX_VISIBILITY(default) 47 { 48 _GLIBCXX_BEGIN_NAMESPACE_VERSION 49 50 /** 51 * @addtogroup allocators 52 * @{ 53 */ 54 55 template<typename _OuterAlloc, typename... _InnerAllocs> 56 class scoped_allocator_adaptor; 57 58 /// @cond undocumented 59 60 template<typename _Alloc> 61 using __outer_allocator_t 62 = decltype(std::declval<_Alloc>().outer_allocator()); 63 64 template<typename _Alloc, typename = void> 65 struct __outermost_type 66 { 67 using type = _Alloc; 68 static type& _S_outermost(_Alloc& __a) noexcept { return __a; } 69 }; 70 71 template<typename _Alloc> 72 struct __outermost_type<_Alloc, __void_t<__outer_allocator_t<_Alloc>>> 73 : __outermost_type< 74 typename remove_reference<__outer_allocator_t<_Alloc>>::type 75 > 76 { 77 using __base = __outermost_type< 78 typename remove_reference<__outer_allocator_t<_Alloc>>::type 79 >; 80 81 static typename __base::type& 82 _S_outermost(_Alloc& __a) noexcept 83 { return __base::_S_outermost(__a.outer_allocator()); } 84 }; 85 86 // Implementation of the OUTERMOST pseudofunction 87 template<typename _Alloc> 88 inline typename __outermost_type<_Alloc>::type& 89 __outermost(_Alloc& __a) 90 { return __outermost_type<_Alloc>::_S_outermost(__a); } 91 92 template<typename...> 93 struct __inner_type_impl; 94 95 template<typename _Outer> 96 struct __inner_type_impl<_Outer> 97 { 98 typedef scoped_allocator_adaptor<_Outer> __type; 99 100 __inner_type_impl() = default; 101 __inner_type_impl(const __inner_type_impl&) = default; 102 __inner_type_impl(__inner_type_impl&&) = default; 103 __inner_type_impl& operator=(const __inner_type_impl&) = default; 104 __inner_type_impl& operator=(__inner_type_impl&&) = default; 105 106 template<typename _Alloc> 107 __inner_type_impl(const __inner_type_impl<_Alloc>& __other) noexcept 108 { } 109 110 template<typename _Alloc> 111 __inner_type_impl(__inner_type_impl<_Alloc>&& __other) noexcept 112 { } 113 114 __type& 115 _M_get(__type* __p) noexcept { return *__p; } 116 117 const __type& 118 _M_get(const __type* __p) const noexcept { return *__p; } 119 120 tuple<> 121 _M_tie() const noexcept { return tuple<>(); } 122 123 bool 124 operator==(const __inner_type_impl&) const noexcept 125 { return true; } 126 }; 127 128 template<typename _Outer, typename _InnerHead, typename... _InnerTail> 129 struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...> 130 { 131 typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type; 132 133 __inner_type_impl() = default; 134 __inner_type_impl(const __inner_type_impl&) = default; 135 __inner_type_impl(__inner_type_impl&&) = default; 136 __inner_type_impl& operator=(const __inner_type_impl&) = default; 137 __inner_type_impl& operator=(__inner_type_impl&&) = default; 138 139 template<typename... _Allocs> 140 __inner_type_impl(const __inner_type_impl<_Allocs...>& __other) noexcept 141 : _M_inner(__other._M_inner) { } 142 143 template<typename... _Allocs> 144 __inner_type_impl(__inner_type_impl<_Allocs...>&& __other) noexcept 145 : _M_inner(std::move(__other._M_inner)) { } 146 147 template<typename... _Args> 148 explicit 149 __inner_type_impl(_Args&&... __args) noexcept 150 : _M_inner(std::forward<_Args>(__args)...) { } 151 152 __type& 153 _M_get(void*) noexcept { return _M_inner; } 154 155 const __type& 156 _M_get(const void*) const noexcept { return _M_inner; } 157 158 tuple<const _InnerHead&, const _InnerTail&...> 159 _M_tie() const noexcept 160 { return _M_inner._M_tie(); } 161 162 bool 163 operator==(const __inner_type_impl& __other) const noexcept 164 { return _M_inner == __other._M_inner; } 165 166 private: 167 template<typename...> friend struct __inner_type_impl; 168 template<typename, typename...> friend class scoped_allocator_adaptor; 169 170 __type _M_inner; 171 }; 172 173 /// @endcond 174 175 /// An adaptor to recursively pass an allocator to the objects it constructs 176 template<typename _OuterAlloc, typename... _InnerAllocs> 177 class scoped_allocator_adaptor 178 : public _OuterAlloc 179 { 180 typedef allocator_traits<_OuterAlloc> __traits; 181 182 typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type; 183 __inner_type _M_inner; 184 185 template<typename _Outer, typename... _Inner> 186 friend class scoped_allocator_adaptor; 187 188 template<typename...> 189 friend struct __inner_type_impl; 190 191 tuple<const _OuterAlloc&, const _InnerAllocs&...> 192 _M_tie() const noexcept 193 { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); } 194 195 template<typename _Alloc> 196 using __outermost_alloc_traits 197 = allocator_traits<typename __outermost_type<_Alloc>::type>; 198 199 #if ! __cpp_lib_make_obj_using_allocator 200 template<typename _Tp, typename... _Args> 201 void 202 _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args) 203 { 204 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 205 _O_traits::construct(__outermost(*this), __p, 206 std::forward<_Args>(__args)...); 207 } 208 209 typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_; 210 typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_; 211 212 template<typename _Tp, typename... _Args> 213 void 214 _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args) 215 { 216 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 217 _O_traits::construct(__outermost(*this), __p, 218 allocator_arg, inner_allocator(), 219 std::forward<_Args>(__args)...); 220 } 221 222 template<typename _Tp, typename... _Args> 223 void 224 _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args) 225 { 226 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 227 _O_traits::construct(__outermost(*this), __p, 228 std::forward<_Args>(__args)..., 229 inner_allocator()); 230 } 231 #endif // ! make_obj_using_allocator 232 233 template<typename _Alloc> 234 static _Alloc 235 _S_select_on_copy(const _Alloc& __a) 236 { 237 typedef allocator_traits<_Alloc> __a_traits; 238 return __a_traits::select_on_container_copy_construction(__a); 239 } 240 241 template<std::size_t... _Indices> 242 scoped_allocator_adaptor(tuple<const _OuterAlloc&, 243 const _InnerAllocs&...> __refs, 244 _Index_tuple<_Indices...>) 245 : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))), 246 _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...) 247 { } 248 249 // Used to constrain constructors to disallow invalid conversions. 250 template<typename _Alloc> 251 using _Constructible = typename enable_if< 252 is_constructible<_OuterAlloc, _Alloc>::value 253 >::type; 254 255 // _GLIBCXX_RESOLVE_LIB_DEFECTS 256 // 2975. Missing case for pair construction in scoped [...] allocators 257 template<typename _Tp> 258 struct __not_pair { using type = void; }; 259 260 template<typename _Tp, typename _Up> 261 struct __not_pair<pair<_Tp, _Up>> { }; 262 263 public: 264 typedef _OuterAlloc outer_allocator_type; 265 typedef typename __inner_type::__type inner_allocator_type; 266 267 typedef typename __traits::value_type value_type; 268 typedef typename __traits::size_type size_type; 269 typedef typename __traits::difference_type difference_type; 270 typedef typename __traits::pointer pointer; 271 typedef typename __traits::const_pointer const_pointer; 272 typedef typename __traits::void_pointer void_pointer; 273 typedef typename __traits::const_void_pointer const_void_pointer; 274 275 typedef typename __or_< 276 typename __traits::propagate_on_container_copy_assignment, 277 typename allocator_traits<_InnerAllocs>:: 278 propagate_on_container_copy_assignment...>::type 279 propagate_on_container_copy_assignment; 280 281 typedef typename __or_< 282 typename __traits::propagate_on_container_move_assignment, 283 typename allocator_traits<_InnerAllocs>:: 284 propagate_on_container_move_assignment...>::type 285 propagate_on_container_move_assignment; 286 287 typedef typename __or_< 288 typename __traits::propagate_on_container_swap, 289 typename allocator_traits<_InnerAllocs>:: 290 propagate_on_container_swap...>::type 291 propagate_on_container_swap; 292 293 typedef typename __and_< 294 typename __traits::is_always_equal, 295 typename allocator_traits<_InnerAllocs>::is_always_equal...>::type 296 is_always_equal; 297 298 template <class _Tp> 299 struct rebind 300 { 301 typedef scoped_allocator_adaptor< 302 typename __traits::template rebind_alloc<_Tp>, 303 _InnerAllocs...> other; 304 }; 305 306 scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { } 307 308 template<typename _Outer2, typename = _Constructible<_Outer2>> 309 scoped_allocator_adaptor(_Outer2&& __outer, 310 const _InnerAllocs&... __inner) noexcept 311 : _OuterAlloc(std::forward<_Outer2>(__outer)), 312 _M_inner(__inner...) 313 { } 314 315 scoped_allocator_adaptor(const scoped_allocator_adaptor& __other) noexcept 316 : _OuterAlloc(__other.outer_allocator()), 317 _M_inner(__other._M_inner) 318 { } 319 320 scoped_allocator_adaptor(scoped_allocator_adaptor&& __other) noexcept 321 : _OuterAlloc(std::move(__other.outer_allocator())), 322 _M_inner(std::move(__other._M_inner)) 323 { } 324 325 template<typename _Outer2, typename = _Constructible<const _Outer2&>> 326 scoped_allocator_adaptor( 327 const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other 328 ) noexcept 329 : _OuterAlloc(__other.outer_allocator()), 330 _M_inner(__other._M_inner) 331 { } 332 333 template<typename _Outer2, typename = _Constructible<_Outer2>> 334 scoped_allocator_adaptor( 335 scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other) noexcept 336 : _OuterAlloc(std::move(__other.outer_allocator())), 337 _M_inner(std::move(__other._M_inner)) 338 { } 339 340 scoped_allocator_adaptor& 341 operator=(const scoped_allocator_adaptor&) = default; 342 343 scoped_allocator_adaptor& 344 operator=(scoped_allocator_adaptor&&) = default; 345 346 inner_allocator_type& 347 inner_allocator() noexcept 348 { return _M_inner._M_get(this); } 349 350 const inner_allocator_type& 351 inner_allocator() const noexcept 352 { return _M_inner._M_get(this); } 353 354 outer_allocator_type& 355 outer_allocator() noexcept 356 { return static_cast<_OuterAlloc&>(*this); } 357 358 const outer_allocator_type& 359 outer_allocator() const noexcept 360 { return static_cast<const _OuterAlloc&>(*this); } 361 362 _GLIBCXX_NODISCARD pointer 363 allocate(size_type __n) 364 { return __traits::allocate(outer_allocator(), __n); } 365 366 _GLIBCXX_NODISCARD pointer 367 allocate(size_type __n, const_void_pointer __hint) 368 { return __traits::allocate(outer_allocator(), __n, __hint); } 369 370 void deallocate(pointer __p, size_type __n) noexcept 371 { return __traits::deallocate(outer_allocator(), __p, __n); } 372 373 size_type max_size() const 374 { return __traits::max_size(outer_allocator()); } 375 376 #if ! __cpp_lib_make_obj_using_allocator 377 template<typename _Tp, typename... _Args> 378 typename __not_pair<_Tp>::type 379 construct(_Tp* __p, _Args&&... __args) 380 { 381 auto& __inner = inner_allocator(); 382 auto __use_tag 383 = std::__use_alloc<_Tp, inner_allocator_type, _Args...>(__inner); 384 _M_construct(__use_tag, __p, std::forward<_Args>(__args)...); 385 } 386 387 template<typename _T1, typename _T2, typename... _Args1, 388 typename... _Args2> 389 void 390 construct(pair<_T1, _T2>* __p, piecewise_construct_t, 391 tuple<_Args1...> __x, tuple<_Args2...> __y) 392 { 393 // _GLIBCXX_RESOLVE_LIB_DEFECTS 394 // 2203. wrong argument types for piecewise construction 395 auto& __inner = inner_allocator(); 396 auto __x_use_tag 397 = std::__use_alloc<_T1, inner_allocator_type, _Args1...>(__inner); 398 auto __y_use_tag 399 = std::__use_alloc<_T2, inner_allocator_type, _Args2...>(__inner); 400 typename _Build_index_tuple<sizeof...(_Args1)>::__type __x_indices; 401 typename _Build_index_tuple<sizeof...(_Args2)>::__type __y_indices; 402 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 403 _O_traits::construct(__outermost(*this), __p, piecewise_construct, 404 _M_construct_p(__x_use_tag, __x_indices, __x), 405 _M_construct_p(__y_use_tag, __y_indices, __y)); 406 } 407 408 template<typename _T1, typename _T2> 409 void 410 construct(pair<_T1, _T2>* __p) 411 { construct(__p, piecewise_construct, tuple<>(), tuple<>()); } 412 413 template<typename _T1, typename _T2, typename _Up, typename _Vp> 414 void 415 construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v) 416 { 417 construct(__p, piecewise_construct, 418 std::forward_as_tuple(std::forward<_Up>(__u)), 419 std::forward_as_tuple(std::forward<_Vp>(__v))); 420 } 421 422 template<typename _T1, typename _T2, typename _Up, typename _Vp> 423 void 424 construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x) 425 { 426 construct(__p, piecewise_construct, 427 std::forward_as_tuple(__x.first), 428 std::forward_as_tuple(__x.second)); 429 } 430 431 template<typename _T1, typename _T2, typename _Up, typename _Vp> 432 void 433 construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x) 434 { 435 construct(__p, piecewise_construct, 436 std::forward_as_tuple(std::forward<_Up>(__x.first)), 437 std::forward_as_tuple(std::forward<_Vp>(__x.second))); 438 } 439 #else // make_obj_using_allocator 440 template<typename _Tp, typename... _Args> 441 __attribute__((__nonnull__)) 442 void 443 construct(_Tp* __p, _Args&&... __args) 444 { 445 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 446 std::apply([__p, this](auto&&... __newargs) { 447 _O_traits::construct(__outermost(*this), __p, 448 std::forward<decltype(__newargs)>(__newargs)...); 449 }, 450 uses_allocator_construction_args<_Tp>(inner_allocator(), 451 std::forward<_Args>(__args)...)); 452 } 453 #endif 454 455 template<typename _Tp> 456 void destroy(_Tp* __p) 457 { 458 typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; 459 _O_traits::destroy(__outermost(*this), __p); 460 } 461 462 scoped_allocator_adaptor 463 select_on_container_copy_construction() const 464 { 465 typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type 466 _Indices; 467 return scoped_allocator_adaptor(_M_tie(), _Indices()); 468 } 469 470 template <typename _OutA1, typename _OutA2, typename... _InA> 471 friend bool 472 operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 473 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept; 474 475 private: 476 #if ! __cpp_lib_make_obj_using_allocator 477 template<typename _Ind, typename... _Args> 478 tuple<_Args&&...> 479 _M_construct_p(__uses_alloc0, _Ind, tuple<_Args...>& __t) 480 { return std::move(__t); } 481 482 template<size_t... _Ind, typename... _Args> 483 tuple<allocator_arg_t, inner_allocator_type&, _Args&&...> 484 _M_construct_p(__uses_alloc1_, _Index_tuple<_Ind...>, 485 tuple<_Args...>& __t) 486 { 487 return { allocator_arg, inner_allocator(), 488 std::get<_Ind>(std::move(__t))... 489 }; 490 } 491 492 template<size_t... _Ind, typename... _Args> 493 tuple<_Args&&..., inner_allocator_type&> 494 _M_construct_p(__uses_alloc2_, _Index_tuple<_Ind...>, 495 tuple<_Args...>& __t) 496 { 497 return { std::get<_Ind>(std::move(__t))..., inner_allocator() }; 498 } 499 #endif // ! make_obj_using_allocator 500 }; 501 502 /// @related std::scoped_allocator_adaptor 503 template <typename _OutA1, typename _OutA2, typename... _InA> 504 inline bool 505 operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 506 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept 507 { 508 return __a.outer_allocator() == __b.outer_allocator() 509 && __a._M_inner == __b._M_inner; 510 } 511 512 #if __cpp_impl_three_way_comparison < 201907L 513 /// @related std::scoped_allocator_adaptor 514 template <typename _OutA1, typename _OutA2, typename... _InA> 515 inline bool 516 operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, 517 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept 518 { return !(__a == __b); } 519 #endif 520 521 /// @} 522 523 _GLIBCXX_END_NAMESPACE_VERSION 524 } // namespace 525 526 #endif // C++11 527 528 #endif // _SCOPED_ALLOCATOR 529
Indexes created Mon Oct 26 00:26:21 UTC 2026