libstdc++-v3/include/std/scoped_allocator

   1 // <scoped_allocator> -*- C++ -*-
   2
   3 // Copyright (C) 2011-2015 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       __inner_type_impl& operator=(const __inner_type_impl&) = default;
 109       __inner_type_impl& operator=(__inner_type_impl&&) = default;
 110
 111       template<typename _Alloc>
 112       __inner_type_impl(const __inner_type_impl<_Alloc>& __other)
 113       { }
 114
 115       template<typename _Alloc>
 116       __inner_type_impl(__inner_type_impl<_Alloc>&& __other)
 117       { }
 118
 119       __type&
 120       _M_get(__type* __p) noexcept { return *__p; }
 121
 122       const __type&
 123       _M_get(const __type* __p) const noexcept { return *__p; }
 124
 125       tuple<>
 126       _M_tie() const noexcept { return tuple<>(); }
 127
 128       bool
 129       operator==(const __inner_type_impl&) const noexcept
 130       { return true; }
 131     };
 132
 133   template<typename _Outer, typename _InnerHead, typename... _InnerTail>
 134     struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...>
 135     {
 136       typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type;
 137
 138       __inner_type_impl() = default;
 139       __inner_type_impl(const __inner_type_impl&) = default;
 140       __inner_type_impl(__inner_type_impl&&) = default;
 141       __inner_type_impl& operator=(const __inner_type_impl&) = default;
 142       __inner_type_impl& operator=(__inner_type_impl&&) = default;
 143
 144       template<typename... _Allocs>
 145       __inner_type_impl(const __inner_type_impl<_Allocs...>& __other)
 146       : _M_inner(__other._M_inner) { }
 147
 148       template<typename... _Allocs>
 149       __inner_type_impl(__inner_type_impl<_Allocs...>&& __other)
 150       : _M_inner(std::move(__other._M_inner)) { }
 151
 152     template<typename... _Args>
 153       explicit
 154       __inner_type_impl(_Args&&... __args)
 155       : _M_inner(std::forward<_Args>(__args)...) { }
 156
 157       __type&
 158       _M_get(void*) noexcept { return _M_inner; }
 159
 160       const __type&
 161       _M_get(const void*) const noexcept { return _M_inner; }
 162
 163       tuple<const _InnerHead&, const _InnerTail&...>
 164       _M_tie() const noexcept
 165       { return _M_inner._M_tie(); }
 166
 167       bool
 168       operator==(const __inner_type_impl& __other) const noexcept
 169       { return _M_inner == __other._M_inner; }
 170
 171     private:
 172       template<typename...> friend class __inner_type_impl;
 173       template<typename, typename...> friend class scoped_allocator_adaptor;
 174
 175       __type _M_inner;
 176     };
 177
 178   /// Primary class template.
 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 class __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_type = typename
 200           std::decay<decltype(__outermost(std::declval<_Alloc&>()))>::type;
 201
 202       template<typename _Alloc>
 203         using __outermost_alloc_traits
 204           = allocator_traits<__outermost_type<_Alloc>>;
 205
 206       template<typename _Tp, typename... _Args>
 207         void
 208         _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args)
 209         {
 210           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 211           _O_traits::construct(__outermost(*this), __p,
 212                                std::forward<_Args>(__args)...);
 213         }
 214
 215       typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_;
 216       typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_;
 217
 218       template<typename _Tp, typename... _Args>
 219         void
 220         _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args)
 221         {
 222           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 223           _O_traits::construct(__outermost(*this), __p,
 224                                allocator_arg, inner_allocator(),
 225                                std::forward<_Args>(__args)...);
 226         }
 227
 228       template<typename _Tp, typename... _Args>
 229         void
 230         _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args)
 231         {
 232           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 233           _O_traits::construct(__outermost(*this), __p,
 234                                std::forward<_Args>(__args)...,
 235                                inner_allocator());
 236         }
 237
 238       template<typename _Alloc>
 239         static _Alloc
 240         _S_select_on_copy(const _Alloc& __a)
 241         {
 242           typedef allocator_traits<_Alloc> __a_traits;
 243           return __a_traits::select_on_container_copy_construction(__a);
 244         }
 245
 246       template<std::size_t... _Indices>
 247         scoped_allocator_adaptor(tuple<const _OuterAlloc&,
 248                                        const _InnerAllocs&...> __refs,
 249                                  _Index_tuple<_Indices...>)
 250         : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))),
 251           _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...)
 252         { }
 253
 254     public:
 255       typedef _OuterAlloc                       outer_allocator_type;
 256       typedef typename __inner_type::__type     inner_allocator_type;
 257
 258       typedef typename __traits::value_type             value_type;
 259       typedef typename __traits::size_type              size_type;
 260       typedef typename __traits::difference_type        difference_type;
 261       typedef typename __traits::pointer                pointer;
 262       typedef typename __traits::const_pointer          const_pointer;
 263       typedef typename __traits::void_pointer           void_pointer;
 264       typedef typename __traits::const_void_pointer     const_void_pointer;
 265
 266       typedef typename conditional<
 267         __any_of<__propagate_on_copy, _OuterAlloc, _InnerAllocs...>::value,
 268         true_type, false_type>::type propagate_on_container_copy_assignment;
 269       typedef typename conditional<
 270         __any_of<__propagate_on_move, _OuterAlloc, _InnerAllocs...>::value,
 271         true_type, false_type>::type propagate_on_container_move_assignment;
 272       typedef typename conditional<
 273         __any_of<__propagate_on_swap, _OuterAlloc, _InnerAllocs...>::value,
 274         true_type, false_type>::type propagate_on_container_swap;
 275
 276       template <class _Tp>
 277         struct rebind
 278         {
 279           typedef scoped_allocator_adaptor<
 280             typename __traits::template rebind_alloc<_Tp>,
 281             _InnerAllocs...> other;
 282         };
 283
 284       scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { }
 285
 286       template<typename _Outer2>
 287         scoped_allocator_adaptor(_Outer2&& __outer,
 288                                  const _InnerAllocs&... __inner)
 289         : _OuterAlloc(std::forward<_Outer2>(__outer)),
 290           _M_inner(__inner...)
 291         { }
 292
 293       scoped_allocator_adaptor(const scoped_allocator_adaptor& __other)
 294       : _OuterAlloc(__other.outer_allocator()),
 295         _M_inner(__other._M_inner)
 296       { }
 297
 298       scoped_allocator_adaptor(scoped_allocator_adaptor&& __other)
 299       : _OuterAlloc(std::move(__other.outer_allocator())),
 300         _M_inner(std::move(__other._M_inner))
 301       { }
 302
 303       template<typename _Outer2>
 304         scoped_allocator_adaptor(
 305             const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other)
 306         : _OuterAlloc(__other.outer_allocator()),
 307           _M_inner(__other._M_inner)
 308         { }
 309
 310       template<typename _Outer2>
 311         scoped_allocator_adaptor(
 312             scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other)
 313         : _OuterAlloc(std::move(__other.outer_allocator())),
 314           _M_inner(std::move(__other._M_inner))
 315         { }
 316
 317       scoped_allocator_adaptor&
 318       operator=(const scoped_allocator_adaptor&) = default;
 319
 320       scoped_allocator_adaptor&
 321       operator=(scoped_allocator_adaptor&&) = default;
 322
 323       inner_allocator_type& inner_allocator() noexcept
 324       { return _M_inner._M_get(this); }
 325
 326       const inner_allocator_type& inner_allocator() const noexcept
 327       { return _M_inner._M_get(this); }
 328
 329       outer_allocator_type& outer_allocator() noexcept
 330       { return static_cast<_OuterAlloc&>(*this); }
 331
 332       const outer_allocator_type& outer_allocator() const noexcept
 333       { return static_cast<const _OuterAlloc&>(*this); }
 334
 335       pointer allocate(size_type __n)
 336       { return __traits::allocate(outer_allocator(), __n); }
 337
 338       pointer allocate(size_type __n, const_void_pointer __hint)
 339       { return __traits::allocate(outer_allocator(), __n, __hint); }
 340
 341       void deallocate(pointer __p, size_type __n)
 342       { return __traits::deallocate(outer_allocator(), __p, __n); }
 343
 344       size_type max_size() const
 345       { return __traits::max_size(outer_allocator()); }
 346
 347       template<typename _Tp, typename... _Args>
 348         void construct(_Tp* __p, _Args&&... __args)
 349         {
 350           auto& __inner = inner_allocator();
 351           auto __use_tag
 352             = __use_alloc<_Tp, inner_allocator_type, _Args...>(__inner);
 353           _M_construct(__use_tag, __p, std::forward<_Args>(__args)...);
 354         }
 355
 356       template<typename _T1, typename _T2, typename... _Args1,
 357                typename... _Args2>
 358         void
 359         construct(pair<_T1, _T2>* __p, piecewise_construct_t,
 360                   tuple<_Args1...> __x, tuple<_Args2...> __y)
 361         {
 362           // _GLIBCXX_RESOLVE_LIB_DEFECTS
 363           // 2203.  wrong argument types for piecewise construction
 364           auto& __inner = inner_allocator();
 365           auto __x_use_tag
 366             = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
 367           auto __y_use_tag
 368             = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
 369           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 370           _O_traits::construct(__outermost(*this), __p, piecewise_construct,
 371                                _M_construct_p(__x_use_tag, __x),
 372                                _M_construct_p(__y_use_tag, __y));
 373         }
 374
 375       template<typename _T1, typename _T2>
 376         void
 377         construct(pair<_T1, _T2>* __p)
 378         { construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
 379
 380       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 381         void
 382         construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
 383         {
 384           construct(__p, piecewise_construct,
 385                     std::forward_as_tuple(std::forward<_Up>(__u)),
 386                     std::forward_as_tuple(std::forward<_Vp>(__v)));
 387         }
 388
 389       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 390         void
 391         construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
 392         {
 393           construct(__p, piecewise_construct,
 394                     std::forward_as_tuple(__x.first),
 395                     std::forward_as_tuple(__x.second));
 396         }
 397
 398       template<typename _T1, typename _T2, typename _Up, typename _Vp>
 399         void
 400         construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
 401         {
 402           construct(__p, piecewise_construct,
 403                     std::forward_as_tuple(std::forward<_Up>(__x.first)),
 404                     std::forward_as_tuple(std::forward<_Vp>(__x.second)));
 405         }
 406
 407       template<typename _Tp>
 408         void destroy(_Tp* __p)
 409         {
 410           typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
 411           _O_traits::destroy(__outermost(*this), __p);
 412         }
 413
 414       scoped_allocator_adaptor
 415       select_on_container_copy_construction() const
 416       {
 417         typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
 418             _Indices;
 419         return scoped_allocator_adaptor(_M_tie(), _Indices());
 420       }
 421
 422       template <typename _OutA1, typename _OutA2, typename... _InA>
 423       friend bool
 424       operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 425                  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
 426
 427     private:
 428       template<typename _Tuple>
 429         _Tuple&&
 430         _M_construct_p(__uses_alloc0, _Tuple& __t)
 431         { return std::move(__t); }
 432
 433       template<typename... _Args>
 434         std::tuple<allocator_arg_t, inner_allocator_type&, _Args...>
 435         _M_construct_p(__uses_alloc1_, std::tuple<_Args...>& __t)
 436         {
 437           typedef std::tuple<allocator_arg_t, inner_allocator_type&> _Tuple;
 438           return std::tuple_cat(_Tuple(allocator_arg, inner_allocator()),
 439                                 std::move(__t));
 440         }
 441
 442       template<typename... _Args>
 443         std::tuple<_Args..., inner_allocator_type&>
 444         _M_construct_p(__uses_alloc2_, std::tuple<_Args...>& __t)
 445         {
 446           typedef std::tuple<inner_allocator_type&> _Tuple;
 447           return std::tuple_cat(std::move(__t), _Tuple(inner_allocator()));
 448         }
 449     };
 450
 451   template <typename _OutA1, typename _OutA2, typename... _InA>
 452     inline bool
 453     operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 454                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
 455     {
 456       return __a.outer_allocator() == __b.outer_allocator()
 457           && __a._M_inner == __b._M_inner;
 458     }
 459
 460   template <typename _OutA1, typename _OutA2, typename... _InA>
 461     inline bool
 462     operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
 463                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
 464     { return !(__a == __b); }
 465
 466   /// @}
 467
 468 _GLIBCXX_END_NAMESPACE_VERSION
 469 } // namespace
 470
 471 #endif // C++11
 472
 473 #endif // _SCOPED_ALLOCATOR