1// <scoped_allocator> -*- C++ -*-
2
3// Copyright (C) 2011-2018 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
42namespace std _GLIBCXX_VISIBILITY(default)
43{
44_GLIBCXX_BEGIN_NAMESPACE_VERSION
45
46  /**
47   * @addtogroup allocators
48   * @{
49   */
50
51  template<typename _Alloc>
52    using __outer_allocator_t
53      = decltype(std::declval<_Alloc>().outer_allocator());
54
55  template<typename _Alloc, typename = void>
56    struct __outermost_type
57    {
58      using type = _Alloc;
59      static type& _S_outermost(_Alloc& __a) { return __a; }
60    };
61
62  template<typename _Alloc>
63    struct __outermost_type<_Alloc, __void_t<__outer_allocator_t<_Alloc>>>
64    : __outermost_type<
65      typename remove_reference<__outer_allocator_t<_Alloc>>::type
66    >
67    {
68      using __base = __outermost_type<
69        typename remove_reference<__outer_allocator_t<_Alloc>>::type
70      >;
71
72      static typename __base::type&
73      _S_outermost(_Alloc& __a)
74      { return __base::_S_outermost(__a.outer_allocator()); }
75    };
76
77  template<typename _Alloc>
78    inline typename __outermost_type<_Alloc>::type&
79    __outermost(_Alloc& __a)
80    { return __outermost_type<_Alloc>::_S_outermost(__a); }
81
82  template<typename _OuterAlloc, typename... _InnerAllocs>
83    class scoped_allocator_adaptor;
84
85  template<typename...>
86    struct __inner_type_impl;
87
88  template<typename _Outer>
89    struct __inner_type_impl<_Outer>
90    {
91      typedef scoped_allocator_adaptor<_Outer> __type;
92
93      __inner_type_impl() = default;
94      __inner_type_impl(const __inner_type_impl&) = default;
95      __inner_type_impl(__inner_type_impl&&) = default;
96      __inner_type_impl& operator=(const __inner_type_impl&) = default;
97      __inner_type_impl& operator=(__inner_type_impl&&) = default;
98
99      template<typename _Alloc>
100      __inner_type_impl(const __inner_type_impl<_Alloc>& __other)
101      { }
102
103      template<typename _Alloc>
104      __inner_type_impl(__inner_type_impl<_Alloc>&& __other)
105      { }
106
107      __type&
108      _M_get(__type* __p) noexcept { return *__p; }
109
110      const __type&
111      _M_get(const __type* __p) const noexcept { return *__p; }
112
113      tuple<>
114      _M_tie() const noexcept { return tuple<>(); }
115
116      bool
117      operator==(const __inner_type_impl&) const noexcept
118      { return true; }
119    };
120
121  template<typename _Outer, typename _InnerHead, typename... _InnerTail>
122    struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...>
123    {
124      typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type;
125
126      __inner_type_impl() = default;
127      __inner_type_impl(const __inner_type_impl&) = default;
128      __inner_type_impl(__inner_type_impl&&) = default;
129      __inner_type_impl& operator=(const __inner_type_impl&) = default;
130      __inner_type_impl& operator=(__inner_type_impl&&) = default;
131
132      template<typename... _Allocs>
133      __inner_type_impl(const __inner_type_impl<_Allocs...>& __other)
134      : _M_inner(__other._M_inner) { }
135
136      template<typename... _Allocs>
137      __inner_type_impl(__inner_type_impl<_Allocs...>&& __other)
138      : _M_inner(std::move(__other._M_inner)) { }
139
140    template<typename... _Args>
141      explicit
142      __inner_type_impl(_Args&&... __args)
143      : _M_inner(std::forward<_Args>(__args)...) { }
144
145      __type&
146      _M_get(void*) noexcept { return _M_inner; }
147
148      const __type&
149      _M_get(const void*) const noexcept { return _M_inner; }
150
151      tuple<const _InnerHead&, const _InnerTail&...>
152      _M_tie() const noexcept
153      { return _M_inner._M_tie(); }
154
155      bool
156      operator==(const __inner_type_impl& __other) const noexcept
157      { return _M_inner == __other._M_inner; }
158
159    private:
160      template<typename...> friend class __inner_type_impl;
161      template<typename, typename...> friend class scoped_allocator_adaptor;
162
163      __type _M_inner;
164    };
165
166  /// Primary class template.
167  template<typename _OuterAlloc, typename... _InnerAllocs>
168    class scoped_allocator_adaptor
169    : public _OuterAlloc
170    {
171      typedef allocator_traits<_OuterAlloc> __traits;
172
173      typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type;
174      __inner_type _M_inner;
175
176      template<typename _Outer, typename... _Inner>
177        friend class scoped_allocator_adaptor;
178
179      template<typename...>
180        friend class __inner_type_impl;
181
182      tuple<const _OuterAlloc&, const _InnerAllocs&...>
183      _M_tie() const noexcept
184      { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); }
185
186      template<typename _Alloc>
187	using __outermost_alloc_traits
188	  = allocator_traits<typename __outermost_type<_Alloc>::type>;
189
190      template<typename _Tp, typename... _Args>
191        void
192        _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args)
193        {
194	  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
195	  _O_traits::construct(__outermost(*this), __p,
196			       std::forward<_Args>(__args)...);
197        }
198
199      typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_;
200      typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_;
201
202      template<typename _Tp, typename... _Args>
203        void
204        _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args)
205        {
206	  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
207	  _O_traits::construct(__outermost(*this), __p,
208			       allocator_arg, inner_allocator(),
209			       std::forward<_Args>(__args)...);
210        }
211
212      template<typename _Tp, typename... _Args>
213        void
214        _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args)
215        {
216	  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
217	  _O_traits::construct(__outermost(*this), __p,
218			       std::forward<_Args>(__args)...,
219			       inner_allocator());
220        }
221
222      template<typename _Alloc>
223        static _Alloc
224        _S_select_on_copy(const _Alloc& __a)
225        {
226          typedef allocator_traits<_Alloc> __a_traits;
227          return __a_traits::select_on_container_copy_construction(__a);
228        }
229
230      template<std::size_t... _Indices>
231        scoped_allocator_adaptor(tuple<const _OuterAlloc&,
232                                       const _InnerAllocs&...> __refs,
233                                 _Index_tuple<_Indices...>)
234        : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))),
235          _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...)
236        { }
237
238      // Used to constrain constructors to disallow invalid conversions.
239      template<typename _Alloc>
240        using _Constructible = typename enable_if<
241            is_constructible<_OuterAlloc, _Alloc>::value
242          >::type;
243
244    public:
245      typedef _OuterAlloc                       outer_allocator_type;
246      typedef typename __inner_type::__type     inner_allocator_type;
247
248      typedef typename __traits::value_type             value_type;
249      typedef typename __traits::size_type              size_type;
250      typedef typename __traits::difference_type        difference_type;
251      typedef typename __traits::pointer                pointer;
252      typedef typename __traits::const_pointer          const_pointer;
253      typedef typename __traits::void_pointer           void_pointer;
254      typedef typename __traits::const_void_pointer     const_void_pointer;
255
256      typedef typename __or_<
257	typename __traits::propagate_on_container_copy_assignment,
258	typename allocator_traits<_InnerAllocs>::
259	  propagate_on_container_copy_assignment...>::type
260	  propagate_on_container_copy_assignment;
261
262      typedef typename __or_<
263	typename __traits::propagate_on_container_move_assignment,
264	typename allocator_traits<_InnerAllocs>::
265	  propagate_on_container_move_assignment...>::type
266	  propagate_on_container_move_assignment;
267
268      typedef typename __or_<
269	typename __traits::propagate_on_container_swap,
270	typename allocator_traits<_InnerAllocs>::
271	  propagate_on_container_swap...>::type
272	  propagate_on_container_swap;
273
274      typedef typename __and_<
275	typename __traits::is_always_equal,
276	typename allocator_traits<_InnerAllocs>::is_always_equal...>::type
277	  is_always_equal;
278
279      template <class _Tp>
280        struct rebind
281        {
282          typedef scoped_allocator_adaptor<
283            typename __traits::template rebind_alloc<_Tp>,
284            _InnerAllocs...> other;
285        };
286
287      scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { }
288
289      template<typename _Outer2, typename = _Constructible<_Outer2>>
290        scoped_allocator_adaptor(_Outer2&& __outer,
291                                 const _InnerAllocs&... __inner)
292        : _OuterAlloc(std::forward<_Outer2>(__outer)),
293          _M_inner(__inner...)
294        { }
295
296      scoped_allocator_adaptor(const scoped_allocator_adaptor& __other)
297      : _OuterAlloc(__other.outer_allocator()),
298	_M_inner(__other._M_inner)
299      { }
300
301      scoped_allocator_adaptor(scoped_allocator_adaptor&& __other)
302      : _OuterAlloc(std::move(__other.outer_allocator())),
303	_M_inner(std::move(__other._M_inner))
304      { }
305
306      template<typename _Outer2, typename = _Constructible<const _Outer2&>>
307        scoped_allocator_adaptor(
308            const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other)
309        : _OuterAlloc(__other.outer_allocator()),
310          _M_inner(__other._M_inner)
311        { }
312
313      template<typename _Outer2, typename = _Constructible<_Outer2>>
314        scoped_allocator_adaptor(
315            scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other)
316        : _OuterAlloc(std::move(__other.outer_allocator())),
317          _M_inner(std::move(__other._M_inner))
318        { }
319
320      scoped_allocator_adaptor&
321      operator=(const scoped_allocator_adaptor&) = default;
322
323      scoped_allocator_adaptor&
324      operator=(scoped_allocator_adaptor&&) = default;
325
326      inner_allocator_type& inner_allocator() noexcept
327      { return _M_inner._M_get(this); }
328
329      const inner_allocator_type& inner_allocator() const noexcept
330      { return _M_inner._M_get(this); }
331
332      outer_allocator_type& outer_allocator() noexcept
333      { return static_cast<_OuterAlloc&>(*this); }
334
335      const outer_allocator_type& outer_allocator() const noexcept
336      { return static_cast<const _OuterAlloc&>(*this); }
337
338      pointer allocate(size_type __n)
339      { return __traits::allocate(outer_allocator(), __n); }
340
341      pointer allocate(size_type __n, const_void_pointer __hint)
342      { return __traits::allocate(outer_allocator(), __n, __hint); }
343
344      void deallocate(pointer __p, size_type __n)
345      { return __traits::deallocate(outer_allocator(), __p, __n); }
346
347      size_type max_size() const
348      { return __traits::max_size(outer_allocator()); }
349
350      template<typename _Tp, typename... _Args>
351        void construct(_Tp* __p, _Args&&... __args)
352        {
353          auto& __inner = inner_allocator();
354          auto __use_tag
355            = __use_alloc<_Tp, inner_allocator_type, _Args...>(__inner);
356          _M_construct(__use_tag, __p, std::forward<_Args>(__args)...);
357        }
358
359      template<typename _T1, typename _T2, typename... _Args1,
360	       typename... _Args2>
361	void
362	construct(pair<_T1, _T2>* __p, piecewise_construct_t,
363		  tuple<_Args1...> __x, tuple<_Args2...> __y)
364	{
365	  // _GLIBCXX_RESOLVE_LIB_DEFECTS
366	  // 2203.  wrong argument types for piecewise construction
367	  auto& __inner = inner_allocator();
368	  auto __x_use_tag
369	    = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
370	  auto __y_use_tag
371	    = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
372	  typename _Build_index_tuple<sizeof...(_Args1)>::__type __x_indices;
373	  typename _Build_index_tuple<sizeof...(_Args2)>::__type __y_indices;
374	  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
375	  _O_traits::construct(__outermost(*this), __p, piecewise_construct,
376			       _M_construct_p(__x_use_tag, __x_indices, __x),
377			       _M_construct_p(__y_use_tag, __y_indices, __y));
378	}
379
380      template<typename _T1, typename _T2>
381	void
382	construct(pair<_T1, _T2>* __p)
383	{ construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
384
385      template<typename _T1, typename _T2, typename _Up, typename _Vp>
386	void
387	construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
388	{
389	  construct(__p, piecewise_construct,
390		    std::forward_as_tuple(std::forward<_Up>(__u)),
391		    std::forward_as_tuple(std::forward<_Vp>(__v)));
392	}
393
394      template<typename _T1, typename _T2, typename _Up, typename _Vp>
395	void
396	construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
397	{
398	  construct(__p, piecewise_construct,
399		    std::forward_as_tuple(__x.first),
400		    std::forward_as_tuple(__x.second));
401	}
402
403      template<typename _T1, typename _T2, typename _Up, typename _Vp>
404	void
405	construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
406	{
407	  construct(__p, piecewise_construct,
408		    std::forward_as_tuple(std::forward<_Up>(__x.first)),
409		    std::forward_as_tuple(std::forward<_Vp>(__x.second)));
410	}
411
412      template<typename _Tp>
413        void destroy(_Tp* __p)
414        {
415	  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
416	  _O_traits::destroy(__outermost(*this), __p);
417	}
418
419      scoped_allocator_adaptor
420      select_on_container_copy_construction() const
421      {
422        typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
423	    _Indices;
424        return scoped_allocator_adaptor(_M_tie(), _Indices());
425      }
426
427      template <typename _OutA1, typename _OutA2, typename... _InA>
428      friend bool
429      operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
430                 const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
431
432    private:
433      template<typename _Ind, typename... _Args>
434	tuple<_Args&&...>
435	_M_construct_p(__uses_alloc0, _Ind, tuple<_Args...>& __t)
436	{ return std::move(__t); }
437
438      template<size_t... _Ind, typename... _Args>
439	tuple<allocator_arg_t, inner_allocator_type&, _Args&&...>
440	_M_construct_p(__uses_alloc1_, _Index_tuple<_Ind...>,
441		       tuple<_Args...>& __t)
442	{
443	  return { allocator_arg, inner_allocator(),
444	      std::get<_Ind>(std::move(__t))...
445	  };
446	}
447
448      template<size_t... _Ind, typename... _Args>
449	tuple<_Args&&..., inner_allocator_type&>
450	_M_construct_p(__uses_alloc2_, _Index_tuple<_Ind...>,
451		       tuple<_Args...>& __t)
452	{
453	  return { std::get<_Ind>(std::move(__t))..., inner_allocator() };
454	}
455    };
456
457  template <typename _OutA1, typename _OutA2, typename... _InA>
458    inline bool
459    operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
460               const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
461    {
462      return __a.outer_allocator() == __b.outer_allocator()
463          && __a._M_inner == __b._M_inner;
464    }
465
466  template <typename _OutA1, typename _OutA2, typename... _InA>
467    inline bool
468    operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
469               const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
470    { return !(__a == __b); }
471
472  /// @}
473
474_GLIBCXX_END_NAMESPACE_VERSION
475} // namespace
476
477#endif // C++11
478
479#endif // _SCOPED_ALLOCATOR
480