libstdc++
scoped_allocator
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1 // <scoped_allocator> -*- C++ -*-
2 
3 // Copyright (C) 2011-2014 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>
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  // _GLIBCXX_RESOLVE_LIB_DEFECTS
353  // 2203. wrong argument types for piecewise construction
354  auto& __inner = inner_allocator();
355  auto __x_use_tag
356  = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
357  auto __y_use_tag
358  = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
359  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
360  _O_traits::construct(__outermost(*this), __p, piecewise_construct,
361  _M_construct_p(__x_use_tag, __x),
362  _M_construct_p(__y_use_tag, __y));
363  }
364 
365  template<typename _T1, typename _T2>
366  void
367  construct(pair<_T1, _T2>* __p)
368  { construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
369 
370  template<typename _T1, typename _T2, typename _Up, typename _Vp>
371  void
372  construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
373  {
374  construct(__p, piecewise_construct,
375  std::forward_as_tuple(std::forward<_Up>(__u)),
376  std::forward_as_tuple(std::forward<_Vp>(__v)));
377  }
378 
379  template<typename _T1, typename _T2, typename _Up, typename _Vp>
380  void
381  construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
382  {
383  construct(__p, piecewise_construct,
384  std::forward_as_tuple(__x.first),
385  std::forward_as_tuple(__x.second));
386  }
387 
388  template<typename _T1, typename _T2, typename _Up, typename _Vp>
389  void
390  construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
391  {
392  construct(__p, piecewise_construct,
393  std::forward_as_tuple(std::forward<_Up>(__x.first)),
394  std::forward_as_tuple(std::forward<_Vp>(__x.second)));
395  }
396 
397  template<typename _Tp>
398  void destroy(_Tp* __p)
399  {
400  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
401  _O_traits::destroy(__outermost(*this), __p);
402  }
403 
404  scoped_allocator_adaptor
405  select_on_container_copy_construction() const
406  {
407  typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
408  _Indices;
409  return scoped_allocator_adaptor(_M_tie(), _Indices());
410  }
411 
412  template <typename _OutA1, typename _OutA2, typename... _InA>
413  friend bool
414  operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
415  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
416 
417  private:
418  template<typename _Tuple>
419  _Tuple&&
420  _M_construct_p(__uses_alloc0, _Tuple& __t)
421  { return std::move(__t); }
422 
423  template<typename... _Args>
424  std::tuple<allocator_arg_t, inner_allocator_type&, _Args...>
425  _M_construct_p(__uses_alloc1_, std::tuple<_Args...>& __t)
426  {
428  return std::tuple_cat(_Tuple(allocator_arg, inner_allocator()),
429  std::move(__t));
430  }
431 
432  template<typename... _Args>
433  std::tuple<_Args..., inner_allocator_type&>
434  _M_construct_p(__uses_alloc2_, std::tuple<_Args...>& __t)
435  {
436  typedef std::tuple<inner_allocator_type&> _Tuple;
437  return std::tuple_cat(std::move(__t), _Tuple(inner_allocator()));
438  }
439  };
440 
441  template <typename _OutA1, typename _OutA2, typename... _InA>
442  inline bool
443  operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
444  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
445  {
446  return __a.outer_allocator() == __b.outer_allocator()
447  && __a._M_inner == __b._M_inner;
448  }
449 
450  template <typename _OutA1, typename _OutA2, typename... _InA>
451  inline bool
452  operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
453  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
454  { return !(__a == __b); }
455 
456  /// @}
457 
458 _GLIBCXX_END_NAMESPACE_VERSION
459 } // namespace
460 
461 #endif // C++11
462 
463 #endif // _SCOPED_ALLOCATOR
__pointer pointer
The allocator&#39;s pointer type.
Primary class template, tuple.
Definition: tuple:388
constexpr piecewise_construct_t piecewise_construct
piecewise_construct
Definition: stl_pair.h:79
Primary class template.
__const_void_pointer const_void_pointer
The allocator&#39;s const void pointer type.
__void_pointer void_pointer
The allocator&#39;s void pointer type.
static void deallocate(_Alloc &__a, pointer __p, size_type __n)
Deallocate memory.
static size_type max_size(const _Alloc &__a) noexcept
The maximum supported allocation size.
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition: move.h:76
__const_pointer const_pointer
The allocator&#39;s const pointer type.
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:72
tuple< _Elements &...> tie(_Elements &...__args) noexcept
tie
Definition: tuple:1048
static pointer allocate(_Alloc &__a, size_type __n)
Allocate memory.
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:75
__difference_type difference_type
The allocator&#39;s difference type.
_Alloc::value_type value_type
The allocated type.
__size_type size_type
The allocator&#39;s size type.