libstdc++-v3/include/std/scoped_allocator

   1 // <scoped_allocator> -*- C++ -*-
   2
   3 // Copyright (C) 2011, 2012 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 <utility>
  39 #include <tuple>
  40 #include <bits/alloc_traits.h>
  41
  42 namespace std _GLIBCXX_VISIBILITY(default)
  43 {
  44 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  45
  46   template<template<typename> class _Pred, typename... _Allocs>
  47     struct __any_of;
  48
  49   template<template<typename> class _Pred, typename _Alloc, typename... _Allocs>
  50     struct __any_of<_Pred, _Alloc, _Allocs...>
  51     : __or_<_Pred<_Alloc>, __any_of<_Pred, _Allocs...>>
  52     { };
  53
  54   template<template<typename> class _Pred, typename _Alloc>
  55     struct __any_of<_Pred, _Alloc>
  56     : _Pred<_Alloc>
  57     { };
  58
  59   /**
  60    * @addtogroup allocators
  61    * @{
  62    */
  63
  64   template<typename _Alloc>
  65     struct __propagate_on_copy
  66     : allocator_traits<_Alloc>::propagate_on_container_copy_assignment
  67     { };
  68   template<typename _Alloc>
  69     struct __propagate_on_move
  70     : allocator_traits<_Alloc>::propagate_on_container_move_assignment
  71     { };
  72   template<typename _Alloc>
  73     struct __propagate_on_swap
  74     : allocator_traits<_Alloc>::propagate_on_container_swap
  75     { };
  76
  77
  78   template<typename _Alloc>
  79     inline auto
  80     __do_outermost(_Alloc& __a, _Alloc*) -> decltype(__a.outer_allocator())
  81     { return __a.outer_allocator(); }
  82
  83   template<typename _Alloc>
  84     inline _Alloc&
  85     __do_outermost(_Alloc& __a, ...)
  86     { return __a; }
  87
  88   // TODO: make recursive (see note in 20.12.4/1)
  89   template<typename _Alloc>
  90     inline auto
  91     __outermost(_Alloc& __a) -> decltype(__do_outermost(__a, &__a))
  92     { return __do_outermost(__a, &__a); }
  93
  94   template<typename _OuterAlloc, typename... _InnerAllocs>
  95     class scoped_allocator_adaptor;
  96
  97   template<typename...>
  98     struct __inner_type_impl;
  99
 100   template<typename _Outer>
 101     struct __inner_type_impl<_Outer>
 102     {
 103       typedef scoped_allocator_adaptor<_Outer> __type;
 104
 105       __inner_type_impl() = default;
 106       __inner_type_impl(const __inner_type_impl&) = default;
 107       __inner_type_impl(__inner_type_impl&&) = default;
 108
 109       template<typename _Alloc>
 110       __inner_type_impl(const __inner_type_impl<_Alloc>& __other)
 111       { }
 112
 113       template<typename _Alloc>
 114       __inner_type_impl(__inner_type_impl<_Alloc>&& __other)
 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
 140       template<typename... _Allocs>
 141       __inner_type_impl(const __inner_type_impl<_Allocs...>& __other)
 142       : _M_inner(__other._M_inner) { }
 143
 144       template<typename... _Allocs>
 145       __inner_type_impl(__inner_type_impl<_Allocs...>&& __other)
 146       : _M_inner(std::move(__other._M_inner)) { }
 147
 148     template<typename... _Args>
 149       explicit
 150       __inner_type_impl(_Args&&... __args)
 151       : _M_inner(std::forward<_Args>(__args)...) { }
 152
 153       __type&
 154       _M_get(void*) noexcept { return _M_inner; }
 155
 156       const __type&
 157       _M_get(const void*) const noexcept { return _M_inner; }
 158
 159       tuple<const _InnerHead&, const _InnerTail&...>
 160       _M_tie() const noexcept
 161       { return _M_inner._M_tie(); }
 162
 163       bool
 164       operator==(const __inner_type_impl& __other) const noexcept
 165       { return _M_inner == __other._M_inner; }
 166
 167     private:
 168       template<typename...> friend class __inner_type_impl;
 169       template<typename, typename...> friend class scoped_allocator_adaptor;
 170
 171       __type _M_inner;
 172     };
 173
 174   /// Primary class template.
 175   template<typename _OuterAlloc, typename... _InnerAllocs>
 176     class scoped_allocator_adaptor
 177     : public _OuterAlloc
 178     {
 179       typedef allocator_traits<_OuterAlloc> __traits;
 180
 181       typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type;
 182       __inner_type _M_inner;
 183
 184       template<typename _Outer, typename... _Inner>
 185         friend class scoped_allocator_adaptor;
 186
 187       template<typename...>
 188         friend class __inner_type_impl;
 189
 190       tuple<const _OuterAlloc&, const _InnerAllocs&...>
 191       _M_tie() const noexcept
 192       { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); }
 193
 194       template<typename _Alloc>
 195         using __outermost_type = typename
 196           std::decay<decltype(__outermost(std::declval<_Alloc&>()))>::type;
 197
 198       template<typename _Alloc>
 199         using __outermost_alloc_traits
 200           = allocator_traits<__outermost_type<_Alloc>>;
 201
 202       template<typename _Tp, typename... _Args>
 203         void
 204         _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args)
 205         {
 206           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 207           _O_traits::construct(__outermost(*this), __p,
 208                                std::forward<_Args>(__args)...);
 209         }
 210
 211       typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_;
 212       typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_;
 213
 214       template<typename _Tp, typename... _Args>
 215         void
 216         _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args)
 217         {
 218           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 219           _O_traits::construct(__outermost(*this), __p,
 220                                allocator_arg, inner_allocator(),
 221                                std::forward<_Args>(__args)...);
 222         }
 223
 224       template<typename _Tp, typename... _Args>
 225         void
 226         _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args)
 227         {
 228           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 229           _O_traits::construct(__outermost(*this), __p,
 230                                std::forward<_Args>(__args)...,
 231                                inner_allocator());
 232         }
 233
 234       template<typename _Alloc>
 235         static _Alloc
 236         _S_select_on_copy(const _Alloc& __a)
 237         {
 238           typedef allocator_traits<_Alloc> __a_traits;
 239           return __a_traits::select_on_container_copy_construction(__a);
 240         }
 241
 242       template<std::size_t... _Indices>
 243         scoped_allocator_adaptor(tuple<const _OuterAlloc&,
 244                                        const _InnerAllocs&...> __refs,
 245                                  _Index_tuple<_Indices...>)
 246         : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))),
 247           _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...)
 248         { }
 249
 250     public:
 251       typedef _OuterAlloc                       outer_allocator_type;
 252       typedef typename __inner_type::__type     inner_allocator_type;
 253
 254       typedef typename __traits::value_type             value_type;
 255       typedef typename __traits::size_type              size_type;
 256       typedef typename __traits::difference_type        difference_type;
 257       typedef typename __traits::pointer                pointer;
 258       typedef typename __traits::const_pointer          const_pointer;
 259       typedef typename __traits::void_pointer           void_pointer;
 260       typedef typename __traits::const_void_pointer     const_void_pointer;
 261
 262       typedef typename conditional<
 263         __any_of<__propagate_on_copy, _OuterAlloc, _InnerAllocs...>::value,
 264         true_type, false_type>::type propagate_on_container_copy_assignment;
 265       typedef typename conditional<
 266         __any_of<__propagate_on_move, _OuterAlloc, _InnerAllocs...>::value,
 267         true_type, false_type>::type propagate_on_container_move_assignment;
 268       typedef typename conditional<
 269         __any_of<__propagate_on_swap, _OuterAlloc, _InnerAllocs...>::value,
 270         true_type, false_type>::type propagate_on_container_swap;
 271
 272       template <class _Tp>
 273         struct rebind
 274         {
 275           typedef scoped_allocator_adaptor<
 276             typename __traits::template rebind_alloc<_Tp>,
 277             _InnerAllocs...> other;
 278         };
 279
 280       scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { }
 281
 282       template<typename _Outer2>
 283         scoped_allocator_adaptor(_Outer2&& __outer,
 284                                  const _InnerAllocs&... __inner)
 285         : _OuterAlloc(std::forward<_Outer2>(__outer)),
 286           _M_inner(__inner...)
 287         { }
 288
 289       scoped_allocator_adaptor(const scoped_allocator_adaptor& __other)
 290       : _OuterAlloc(__other.outer_allocator()),
 291         _M_inner(__other._M_inner)
 292       { }
 293
 294       scoped_allocator_adaptor(scoped_allocator_adaptor&& __other)
 295       : _OuterAlloc(std::move(__other.outer_allocator())),
 296         _M_inner(std::move(__other._M_inner))
 297       { }
 298
 299       template<typename _Outer2>
 300         scoped_allocator_adaptor(
 301             const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other)
 302         : _OuterAlloc(__other.outer_allocator()),
 303           _M_inner(__other._M_inner)
 304         { }
 305
 306       template<typename _Outer2>
 307         scoped_allocator_adaptor(
 308             scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other)
 309         : _OuterAlloc(std::move(__other.outer_allocator())),
 310           _M_inner(std::move(__other._M_inner))
 311         { }
 312
 313       inner_allocator_type& inner_allocator() noexcept
 314       { return _M_inner._M_get(this); }
 315
 316       const inner_allocator_type& inner_allocator() const noexcept
 317       { return _M_inner._M_get(this); }
 318
 319       outer_allocator_type& outer_allocator() noexcept
 320       { return static_cast<_OuterAlloc&>(*this); }
 321
 322       const outer_allocator_type& outer_allocator() const noexcept
 323       { return static_cast<const _OuterAlloc&>(*this); }
 324
 325       pointer allocate(size_type __n)
 326       { return __traits::allocate(outer_allocator(), __n); }
 327
 328       pointer allocate(size_type __n, const_void_pointer __hint)
 329       { return __traits::allocate(outer_allocator(), __n, __hint); }
 330
 331       void deallocate(pointer __p, size_type __n)
 332       { return __traits::deallocate(outer_allocator(), __p, __n); }
 333
 334       size_type max_size() const
 335       { return __traits::max_size(outer_allocator()); }
 336
 337       template<typename _Tp, typename... _Args>
 338         void construct(_Tp* __p, _Args&&... __args)
 339         {
 340           auto& __inner = inner_allocator();
 341           auto __use_tag
 342             = __use_alloc<_Tp, inner_allocator_type, _Args...>(__inner);
 343           _M_construct(__use_tag, __p, std::forward<_Args>(__args)...);
 344         }
 345
 346       template<typename _T1, typename _T2, typename... _Args1,
 347                typename... _Args2>
 348         void
 349         construct(pair<_T1, _T2>* __p, piecewise_construct_t,
 350                   tuple<_Args1...> __x, tuple<_Args2...> __y)
 351         {
 352           auto& __inner = inner_allocator();
 353           auto __x_use_tag
 354             = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
 355           auto __y_use_tag
 356             = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
 357           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 358           _O_traits::construct(__outermost(*this), __p, piecewise_construct,
 359                                _M_construct_p(__x_use_tag, __x),
 360                                _M_construct_p(__y_use_tag, __y));
 361         }
 362
 363       template<typename _T1, typename _T2>
 364         void
 365         construct(pair<_T1, _T2>* __p)
 366         { construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
 367
 368       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 369         void
 370         construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
 371         {
 372           construct(__p, piecewise_construct,
 373                     std::forward_as_tuple(std::forward<_Up>(__u)),
 374                     std::forward_as_tuple(std::forward<_Vp>(__v)));
 375         }
 376
 377       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 378         void
 379         construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
 380         {
 381           construct(__p, piecewise_construct,
 382                     std::forward_as_tuple(__x.first),
 383                     std::forward_as_tuple(__x.second));
 384         }
 385
 386       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 387         void
 388         construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
 389         {
 390           construct(__p, piecewise_construct,
 391                     std::forward_as_tuple(std::forward<_Up>(__x.first)),
 392                     std::forward_as_tuple(std::forward<_Vp>(__x.second)));
 393         }
 394
 395       template<typename _Tp>
 396         void destroy(_Tp* __p)
 397         {
 398           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 399           _O_traits::destroy(__outermost(*this), __p);
 400         }
 401
 402       scoped_allocator_adaptor
 403       select_on_container_copy_construction() const
 404       {
 405         typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
 406             _Indices;
 407         return scoped_allocator_adaptor(_M_tie(), _Indices());
 408       }
 409
 410       template <typename _OutA1, typename _OutA2, typename... _InA>
 411       friend bool
 412       operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 413                  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
 414
 415     private:
 416       template<typename _Tuple>
 417         _Tuple&&
 418         _M_construct_p(__uses_alloc0, _Tuple& __t)
 419         { return std::move(__t); }
 420
 421       template<typename... _Args>
 422         std::tuple<allocator_arg_t, inner_allocator_type&, _Args...>
 423         _M_construct_p(__uses_alloc1_, std::tuple<_Args...>& __t)
 424         {
 425           typedef std::tuple<allocator_arg_t, inner_allocator_type&> _Tuple;
 426           return std::tuple_cat(_Tuple(allocator_arg, inner_allocator()),
 427                                 std::move(__t));
 428         }
 429
 430       template<typename... _Args>
 431         std::tuple<_Args..., inner_allocator_type&>
 432         _M_construct_p(__uses_alloc2_, std::tuple<_Args...>& __t)
 433         {
 434           typedef std::tuple<inner_allocator_type&> _Tuple;
 435           return std::tuple_cat(std::move(__t), _Tuple(inner_allocator()));
 436         }
 437     };
 438
 439   template <typename _OutA1, typename _OutA2, typename... _InA>
 440     inline bool
 441     operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 442                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
 443     {
 444       return __a.outer_allocator() == __b.outer_allocator()
 445           && __a._M_inner == __b._M_inner;
 446     }
 447
 448   template <typename _OutA1, typename _OutA2, typename... _InA>
 449     inline bool
 450     operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 451                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
 452     { return !(__a == __b); }
 453
 454   /// @}
 455
 456 _GLIBCXX_END_NAMESPACE_VERSION
 457 } // namespace
 458
 459 #endif // C++11
 460
 461 #endif // _SCOPED_ALLOCATOR