libstdc++
scoped_allocator
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00001 // <scoped_allocator> -*- C++ -*-
00002 
00003 // Copyright (C) 2011-2013 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file include/scoped_allocator
00026  *  This is a Standard C++ Library header.
00027  */
00028 
00029 #ifndef _SCOPED_ALLOCATOR
00030 #define _SCOPED_ALLOCATOR 1
00031 
00032 #pragma GCC system_header
00033 
00034 #if __cplusplus < 201103L
00035 # include <bits/c++0x_warning.h>
00036 #else
00037 
00038 #include <utility>
00039 #include <tuple>
00040 #include <bits/alloc_traits.h>
00041 
00042 namespace std _GLIBCXX_VISIBILITY(default)
00043 {
00044 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00045 
00046   template<template<typename> class _Pred, typename... _Allocs>
00047     struct __any_of;
00048 
00049   template<template<typename> class _Pred, typename _Alloc, typename... _Allocs>
00050     struct __any_of<_Pred, _Alloc, _Allocs...>
00051     : __or_<_Pred<_Alloc>, __any_of<_Pred, _Allocs...>>
00052     { };
00053 
00054   template<template<typename> class _Pred, typename _Alloc>
00055     struct __any_of<_Pred, _Alloc>
00056     : _Pred<_Alloc>
00057     { };
00058 
00059   /**
00060    * @addtogroup allocators
00061    * @{
00062    */
00063 
00064   template<typename _Alloc>
00065     struct __propagate_on_copy
00066     : allocator_traits<_Alloc>::propagate_on_container_copy_assignment
00067     { };
00068   template<typename _Alloc>
00069     struct __propagate_on_move
00070     : allocator_traits<_Alloc>::propagate_on_container_move_assignment
00071     { };
00072   template<typename _Alloc>
00073     struct __propagate_on_swap
00074     : allocator_traits<_Alloc>::propagate_on_container_swap
00075     { };
00076 
00077 
00078   template<typename _Alloc>
00079     inline auto
00080     __do_outermost(_Alloc& __a, _Alloc*) -> decltype(__a.outer_allocator())
00081     { return __a.outer_allocator(); }
00082 
00083   template<typename _Alloc>
00084     inline _Alloc&
00085     __do_outermost(_Alloc& __a, ...)
00086     { return __a; }
00087 
00088   // TODO: make recursive (see note in 20.12.4/1)
00089   template<typename _Alloc>
00090     inline auto
00091     __outermost(_Alloc& __a) -> decltype(__do_outermost(__a, &__a))
00092     { return __do_outermost(__a, &__a); }
00093 
00094   template<typename _OuterAlloc, typename... _InnerAllocs>
00095     class scoped_allocator_adaptor;
00096 
00097   template<typename...> 
00098     struct __inner_type_impl;
00099 
00100   template<typename _Outer>
00101     struct __inner_type_impl<_Outer>
00102     {
00103       typedef scoped_allocator_adaptor<_Outer> __type;
00104 
00105       __inner_type_impl() = default;
00106       __inner_type_impl(const __inner_type_impl&) = default;
00107       __inner_type_impl(__inner_type_impl&&) = default;
00108       
00109       template<typename _Alloc>
00110       __inner_type_impl(const __inner_type_impl<_Alloc>& __other)
00111       { }
00112       
00113       template<typename _Alloc>
00114       __inner_type_impl(__inner_type_impl<_Alloc>&& __other)
00115       { }
00116       
00117       __type& 
00118       _M_get(__type* __p) noexcept { return *__p; }
00119 
00120       const __type& 
00121       _M_get(const __type* __p) const noexcept { return *__p; }
00122       
00123       tuple<> 
00124       _M_tie() const noexcept { return tuple<>(); }
00125       
00126       bool 
00127       operator==(const __inner_type_impl&) const noexcept
00128       { return true; }
00129     };
00130 
00131   template<typename _Outer, typename _InnerHead, typename... _InnerTail>
00132     struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...>
00133     {
00134       typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type;
00135       
00136       __inner_type_impl() = default;
00137       __inner_type_impl(const __inner_type_impl&) = default;
00138       __inner_type_impl(__inner_type_impl&&) = default;
00139       
00140       template<typename... _Allocs>
00141       __inner_type_impl(const __inner_type_impl<_Allocs...>& __other)
00142       : _M_inner(__other._M_inner) { }
00143       
00144       template<typename... _Allocs>
00145       __inner_type_impl(__inner_type_impl<_Allocs...>&& __other)
00146       : _M_inner(std::move(__other._M_inner)) { }
00147 
00148     template<typename... _Args>
00149       explicit
00150       __inner_type_impl(_Args&&... __args)
00151       : _M_inner(std::forward<_Args>(__args)...) { }
00152 
00153       __type& 
00154       _M_get(void*) noexcept { return _M_inner; }
00155       
00156       const __type& 
00157       _M_get(const void*) const noexcept { return _M_inner; }
00158       
00159       tuple<const _InnerHead&, const _InnerTail&...> 
00160       _M_tie() const noexcept
00161       { return _M_inner._M_tie(); }
00162       
00163       bool 
00164       operator==(const __inner_type_impl& __other) const noexcept
00165       { return _M_inner == __other._M_inner; }
00166       
00167     private:
00168       template<typename...> friend class __inner_type_impl;
00169       template<typename, typename...> friend class scoped_allocator_adaptor;
00170       
00171       __type _M_inner;
00172     };
00173 
00174   /// Primary class template.
00175   template<typename _OuterAlloc, typename... _InnerAllocs>
00176     class scoped_allocator_adaptor
00177     : public _OuterAlloc
00178     {
00179       typedef allocator_traits<_OuterAlloc> __traits;
00180 
00181       typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type;
00182       __inner_type _M_inner;
00183 
00184       template<typename _Outer, typename... _Inner>
00185         friend class scoped_allocator_adaptor;
00186 
00187       template<typename...>
00188         friend class __inner_type_impl;
00189 
00190       tuple<const _OuterAlloc&, const _InnerAllocs&...>
00191       _M_tie() const noexcept
00192       { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); }
00193 
00194       template<typename _Alloc>
00195     using __outermost_type = typename
00196       std::decay<decltype(__outermost(std::declval<_Alloc&>()))>::type;
00197 
00198       template<typename _Alloc>
00199     using __outermost_alloc_traits
00200       = allocator_traits<__outermost_type<_Alloc>>;
00201       
00202       template<typename _Tp, typename... _Args>
00203         void 
00204         _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args)
00205         {
00206       typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
00207       _O_traits::construct(__outermost(*this), __p,
00208                    std::forward<_Args>(__args)...);
00209         }
00210 
00211       typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_;
00212       typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_;
00213 
00214       template<typename _Tp, typename... _Args>
00215         void 
00216         _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args)
00217         {
00218       typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
00219       _O_traits::construct(__outermost(*this), __p,
00220                    allocator_arg, inner_allocator(),
00221                    std::forward<_Args>(__args)...);
00222         }
00223 
00224       template<typename _Tp, typename... _Args>
00225         void 
00226         _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args)
00227         {
00228       typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
00229       _O_traits::construct(__outermost(*this), __p,
00230                    std::forward<_Args>(__args)...,
00231                    inner_allocator());
00232         }
00233 
00234       template<typename _Alloc>
00235         static _Alloc
00236         _S_select_on_copy(const _Alloc& __a)
00237         {
00238           typedef allocator_traits<_Alloc> __a_traits;
00239           return __a_traits::select_on_container_copy_construction(__a);
00240         }
00241 
00242       template<std::size_t... _Indices>
00243         scoped_allocator_adaptor(tuple<const _OuterAlloc&,
00244                                        const _InnerAllocs&...> __refs,
00245                                  _Index_tuple<_Indices...>)
00246         : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))),
00247           _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...)
00248         { }
00249 
00250     public:
00251       typedef _OuterAlloc                       outer_allocator_type;
00252       typedef typename __inner_type::__type     inner_allocator_type;
00253 
00254       typedef typename __traits::value_type             value_type;
00255       typedef typename __traits::size_type              size_type;
00256       typedef typename __traits::difference_type        difference_type;
00257       typedef typename __traits::pointer                pointer;
00258       typedef typename __traits::const_pointer          const_pointer;
00259       typedef typename __traits::void_pointer           void_pointer;
00260       typedef typename __traits::const_void_pointer     const_void_pointer;
00261 
00262       typedef typename conditional<
00263         __any_of<__propagate_on_copy, _OuterAlloc, _InnerAllocs...>::value,
00264         true_type, false_type>::type propagate_on_container_copy_assignment;
00265       typedef typename conditional<
00266         __any_of<__propagate_on_move, _OuterAlloc, _InnerAllocs...>::value,
00267         true_type, false_type>::type propagate_on_container_move_assignment;
00268       typedef typename conditional<
00269         __any_of<__propagate_on_swap, _OuterAlloc, _InnerAllocs...>::value,
00270         true_type, false_type>::type propagate_on_container_swap;
00271 
00272       template <class _Tp>
00273         struct rebind
00274         {
00275           typedef scoped_allocator_adaptor<
00276             typename __traits::template rebind_alloc<_Tp>,
00277             _InnerAllocs...> other;
00278         };
00279 
00280       scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { }
00281 
00282       template<typename _Outer2>
00283         scoped_allocator_adaptor(_Outer2&& __outer,
00284                                  const _InnerAllocs&... __inner)
00285         : _OuterAlloc(std::forward<_Outer2>(__outer)),
00286           _M_inner(__inner...)
00287         { }
00288 
00289       scoped_allocator_adaptor(const scoped_allocator_adaptor& __other)
00290       : _OuterAlloc(__other.outer_allocator()),
00291     _M_inner(__other._M_inner)
00292       { }
00293 
00294       scoped_allocator_adaptor(scoped_allocator_adaptor&& __other)
00295       : _OuterAlloc(std::move(__other.outer_allocator())),
00296     _M_inner(std::move(__other._M_inner))
00297       { }
00298 
00299       template<typename _Outer2>
00300         scoped_allocator_adaptor(
00301             const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other)
00302         : _OuterAlloc(__other.outer_allocator()),
00303           _M_inner(__other._M_inner)
00304         { }
00305 
00306       template<typename _Outer2>
00307         scoped_allocator_adaptor(
00308             scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other)
00309         : _OuterAlloc(std::move(__other.outer_allocator())),
00310           _M_inner(std::move(__other._M_inner))
00311         { }
00312 
00313       inner_allocator_type& inner_allocator() noexcept
00314       { return _M_inner._M_get(this); }
00315 
00316       const inner_allocator_type& inner_allocator() const noexcept
00317       { return _M_inner._M_get(this); }
00318 
00319       outer_allocator_type& outer_allocator() noexcept
00320       { return static_cast<_OuterAlloc&>(*this); }
00321 
00322       const outer_allocator_type& outer_allocator() const noexcept
00323       { return static_cast<const _OuterAlloc&>(*this); }
00324 
00325       pointer allocate(size_type __n)
00326       { return __traits::allocate(outer_allocator(), __n); }
00327 
00328       pointer allocate(size_type __n, const_void_pointer __hint)
00329       { return __traits::allocate(outer_allocator(), __n, __hint); }
00330 
00331       void deallocate(pointer __p, size_type __n)
00332       { return __traits::deallocate(outer_allocator(), __p, __n); }
00333 
00334       size_type max_size() const
00335       { return __traits::max_size(outer_allocator()); }
00336 
00337       template<typename _Tp, typename... _Args>
00338         void construct(_Tp* __p, _Args&&... __args)
00339         {
00340           auto& __inner = inner_allocator();
00341           auto __use_tag
00342             = __use_alloc<_Tp, inner_allocator_type, _Args...>(__inner);
00343           _M_construct(__use_tag, __p, std::forward<_Args>(__args)...);
00344         }
00345 
00346       template<typename _T1, typename _T2, typename... _Args1,
00347            typename... _Args2>
00348     void
00349     construct(pair<_T1, _T2>* __p, piecewise_construct_t,
00350           tuple<_Args1...> __x, tuple<_Args2...> __y)
00351     {
00352       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00353       // 2203.  wrong argument types for piecewise construction
00354       auto& __inner = inner_allocator();
00355       auto __x_use_tag
00356         = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
00357       auto __y_use_tag
00358         = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
00359       typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
00360       _O_traits::construct(__outermost(*this), __p, piecewise_construct,
00361                    _M_construct_p(__x_use_tag, __x),
00362                    _M_construct_p(__y_use_tag, __y));
00363     }
00364 
00365       template<typename _T1, typename _T2>
00366     void
00367     construct(pair<_T1, _T2>* __p)
00368     { construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
00369 
00370       template<typename _T1, typename _T2, typename _Up, typename _Vp>
00371     void
00372     construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
00373     {
00374       construct(__p, piecewise_construct,
00375             std::forward_as_tuple(std::forward<_Up>(__u)),
00376             std::forward_as_tuple(std::forward<_Vp>(__v)));
00377     }
00378 
00379       template<typename _T1, typename _T2, typename _Up, typename _Vp>
00380     void
00381     construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
00382     {
00383       construct(__p, piecewise_construct,
00384             std::forward_as_tuple(__x.first),
00385             std::forward_as_tuple(__x.second));
00386     }
00387 
00388       template<typename _T1, typename _T2, typename _Up, typename _Vp>
00389     void
00390     construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
00391     {
00392       construct(__p, piecewise_construct,
00393             std::forward_as_tuple(std::forward<_Up>(__x.first)),
00394             std::forward_as_tuple(std::forward<_Vp>(__x.second)));
00395     }
00396 
00397       template<typename _Tp>
00398         void destroy(_Tp* __p)
00399         {
00400       typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
00401       _O_traits::destroy(__outermost(*this), __p);
00402     }
00403 
00404       scoped_allocator_adaptor
00405       select_on_container_copy_construction() const
00406       {
00407         typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
00408         _Indices;
00409         return scoped_allocator_adaptor(_M_tie(), _Indices());
00410       }
00411 
00412       template <typename _OutA1, typename _OutA2, typename... _InA>
00413       friend bool
00414       operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
00415                  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
00416 
00417     private:
00418       template<typename _Tuple>
00419     _Tuple&&
00420     _M_construct_p(__uses_alloc0, _Tuple& __t)
00421     { return std::move(__t); }
00422 
00423       template<typename... _Args>
00424     std::tuple<allocator_arg_t, inner_allocator_type&, _Args...>
00425     _M_construct_p(__uses_alloc1_, std::tuple<_Args...>& __t)
00426     {
00427       typedef std::tuple<allocator_arg_t, inner_allocator_type&> _Tuple;
00428       return std::tuple_cat(_Tuple(allocator_arg, inner_allocator()),
00429                 std::move(__t));
00430     }
00431 
00432       template<typename... _Args>
00433     std::tuple<_Args..., inner_allocator_type&>
00434     _M_construct_p(__uses_alloc2_, std::tuple<_Args...>& __t)
00435     {
00436       typedef std::tuple<inner_allocator_type&> _Tuple;
00437       return std::tuple_cat(std::move(__t), _Tuple(inner_allocator()));
00438     }
00439     };
00440 
00441   template <typename _OutA1, typename _OutA2, typename... _InA>
00442     inline bool
00443     operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
00444                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
00445     {
00446       return __a.outer_allocator() == __b.outer_allocator()
00447           && __a._M_inner == __b._M_inner;
00448     }
00449 
00450   template <typename _OutA1, typename _OutA2, typename... _InA>
00451     inline bool
00452     operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
00453                const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
00454     { return !(__a == __b); }
00455 
00456   /// @}
00457 
00458 _GLIBCXX_END_NAMESPACE_VERSION
00459 } // namespace
00460 
00461 #endif // C++11
00462 
00463 #endif // _SCOPED_ALLOCATOR