libstdc++
scoped_allocator
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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  template<typename _Alloc>
78  using __outer_allocator_t
79  = decltype(std::declval<_Alloc>().outer_allocator());
80 
81  template<typename _Alloc, typename = void>
82  struct __outermost_type
83  {
84  using type = _Alloc;
85  static type& _S_outermost(_Alloc& __a) { return __a; }
86  };
87 
88  template<typename _Alloc>
89  struct __outermost_type<_Alloc, __void_t<__outer_allocator_t<_Alloc>>>
90  : __outermost_type<
91  typename remove_reference<__outer_allocator_t<_Alloc>>::type
92  >
93  {
94  using __base = __outermost_type<
95  typename remove_reference<__outer_allocator_t<_Alloc>>::type
96  >;
97 
98  static typename __base::type&
99  _S_outermost(_Alloc& __a)
100  { return __base::_S_outermost(__a.outer_allocator()); }
101  };
102 
103  template<typename _Alloc>
104  inline typename __outermost_type<_Alloc>::type&
105  __outermost(_Alloc& __a)
106  { return __outermost_type<_Alloc>::_S_outermost(__a); }
107 
108  template<typename _OuterAlloc, typename... _InnerAllocs>
109  class scoped_allocator_adaptor;
110 
111  template<typename...>
112  struct __inner_type_impl;
113 
114  template<typename _Outer>
115  struct __inner_type_impl<_Outer>
116  {
117  typedef scoped_allocator_adaptor<_Outer> __type;
118 
119  __inner_type_impl() = default;
120  __inner_type_impl(const __inner_type_impl&) = default;
121  __inner_type_impl(__inner_type_impl&&) = default;
122  __inner_type_impl& operator=(const __inner_type_impl&) = default;
123  __inner_type_impl& operator=(__inner_type_impl&&) = default;
124 
125  template<typename _Alloc>
126  __inner_type_impl(const __inner_type_impl<_Alloc>& __other)
127  { }
128 
129  template<typename _Alloc>
130  __inner_type_impl(__inner_type_impl<_Alloc>&& __other)
131  { }
132 
133  __type&
134  _M_get(__type* __p) noexcept { return *__p; }
135 
136  const __type&
137  _M_get(const __type* __p) const noexcept { return *__p; }
138 
139  tuple<>
140  _M_tie() const noexcept { return tuple<>(); }
141 
142  bool
143  operator==(const __inner_type_impl&) const noexcept
144  { return true; }
145  };
146 
147  template<typename _Outer, typename _InnerHead, typename... _InnerTail>
148  struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...>
149  {
150  typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type;
151 
152  __inner_type_impl() = default;
153  __inner_type_impl(const __inner_type_impl&) = default;
154  __inner_type_impl(__inner_type_impl&&) = default;
155  __inner_type_impl& operator=(const __inner_type_impl&) = default;
156  __inner_type_impl& operator=(__inner_type_impl&&) = default;
157 
158  template<typename... _Allocs>
159  __inner_type_impl(const __inner_type_impl<_Allocs...>& __other)
160  : _M_inner(__other._M_inner) { }
161 
162  template<typename... _Allocs>
163  __inner_type_impl(__inner_type_impl<_Allocs...>&& __other)
164  : _M_inner(std::move(__other._M_inner)) { }
165 
166  template<typename... _Args>
167  explicit
168  __inner_type_impl(_Args&&... __args)
169  : _M_inner(std::forward<_Args>(__args)...) { }
170 
171  __type&
172  _M_get(void*) noexcept { return _M_inner; }
173 
174  const __type&
175  _M_get(const void*) const noexcept { return _M_inner; }
176 
177  tuple<const _InnerHead&, const _InnerTail&...>
178  _M_tie() const noexcept
179  { return _M_inner._M_tie(); }
180 
181  bool
182  operator==(const __inner_type_impl& __other) const noexcept
183  { return _M_inner == __other._M_inner; }
184 
185  private:
186  template<typename...> friend class __inner_type_impl;
187  template<typename, typename...> friend class scoped_allocator_adaptor;
188 
189  __type _M_inner;
190  };
191 
192  /// Primary class template.
193  template<typename _OuterAlloc, typename... _InnerAllocs>
194  class scoped_allocator_adaptor
195  : public _OuterAlloc
196  {
197  typedef allocator_traits<_OuterAlloc> __traits;
198 
199  typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type;
200  __inner_type _M_inner;
201 
202  template<typename _Outer, typename... _Inner>
203  friend class scoped_allocator_adaptor;
204 
205  template<typename...>
206  friend class __inner_type_impl;
207 
208  tuple<const _OuterAlloc&, const _InnerAllocs&...>
209  _M_tie() const noexcept
210  { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); }
211 
212  template<typename _Alloc>
213  using __outermost_alloc_traits
214  = allocator_traits<typename __outermost_type<_Alloc>::type>;
215 
216  template<typename _Tp, typename... _Args>
217  void
218  _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args)
219  {
220  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
221  _O_traits::construct(__outermost(*this), __p,
222  std::forward<_Args>(__args)...);
223  }
224 
225  typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_;
226  typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_;
227 
228  template<typename _Tp, typename... _Args>
229  void
230  _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args)
231  {
232  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
233  _O_traits::construct(__outermost(*this), __p,
234  allocator_arg, inner_allocator(),
235  std::forward<_Args>(__args)...);
236  }
237 
238  template<typename _Tp, typename... _Args>
239  void
240  _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args)
241  {
242  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
243  _O_traits::construct(__outermost(*this), __p,
244  std::forward<_Args>(__args)...,
245  inner_allocator());
246  }
247 
248  template<typename _Alloc>
249  static _Alloc
250  _S_select_on_copy(const _Alloc& __a)
251  {
252  typedef allocator_traits<_Alloc> __a_traits;
253  return __a_traits::select_on_container_copy_construction(__a);
254  }
255 
256  template<std::size_t... _Indices>
257  scoped_allocator_adaptor(tuple<const _OuterAlloc&,
258  const _InnerAllocs&...> __refs,
259  _Index_tuple<_Indices...>)
260  : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))),
261  _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...)
262  { }
263 
264  // Used to constrain constructors to disallow invalid conversions.
265  template<typename _Alloc>
266  using _Constructible = typename enable_if<
267  is_constructible<_OuterAlloc, _Alloc>::value
268  >::type;
269 
270  public:
271  typedef _OuterAlloc outer_allocator_type;
272  typedef typename __inner_type::__type inner_allocator_type;
273 
274  typedef typename __traits::value_type value_type;
275  typedef typename __traits::size_type size_type;
276  typedef typename __traits::difference_type difference_type;
277  typedef typename __traits::pointer pointer;
278  typedef typename __traits::const_pointer const_pointer;
279  typedef typename __traits::void_pointer void_pointer;
280  typedef typename __traits::const_void_pointer const_void_pointer;
281 
282  typedef typename conditional<
283  __any_of<__propagate_on_copy, _OuterAlloc, _InnerAllocs...>::value,
284  true_type, false_type>::type propagate_on_container_copy_assignment;
285  typedef typename conditional<
286  __any_of<__propagate_on_move, _OuterAlloc, _InnerAllocs...>::value,
287  true_type, false_type>::type propagate_on_container_move_assignment;
288  typedef typename conditional<
289  __any_of<__propagate_on_swap, _OuterAlloc, _InnerAllocs...>::value,
290  true_type, false_type>::type propagate_on_container_swap;
291 
292  template <class _Tp>
293  struct rebind
294  {
295  typedef scoped_allocator_adaptor<
296  typename __traits::template rebind_alloc<_Tp>,
297  _InnerAllocs...> other;
298  };
299 
300  scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { }
301 
302  template<typename _Outer2, typename = _Constructible<_Outer2>>
303  scoped_allocator_adaptor(_Outer2&& __outer,
304  const _InnerAllocs&... __inner)
305  : _OuterAlloc(std::forward<_Outer2>(__outer)),
306  _M_inner(__inner...)
307  { }
308 
309  scoped_allocator_adaptor(const scoped_allocator_adaptor& __other)
310  : _OuterAlloc(__other.outer_allocator()),
311  _M_inner(__other._M_inner)
312  { }
313 
314  scoped_allocator_adaptor(scoped_allocator_adaptor&& __other)
315  : _OuterAlloc(std::move(__other.outer_allocator())),
316  _M_inner(std::move(__other._M_inner))
317  { }
318 
319  template<typename _Outer2, typename = _Constructible<const _Outer2&>>
320  scoped_allocator_adaptor(
321  const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other)
322  : _OuterAlloc(__other.outer_allocator()),
323  _M_inner(__other._M_inner)
324  { }
325 
326  template<typename _Outer2, typename = _Constructible<_Outer2>>
327  scoped_allocator_adaptor(
328  scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other)
329  : _OuterAlloc(std::move(__other.outer_allocator())),
330  _M_inner(std::move(__other._M_inner))
331  { }
332 
333  scoped_allocator_adaptor&
334  operator=(const scoped_allocator_adaptor&) = default;
335 
336  scoped_allocator_adaptor&
337  operator=(scoped_allocator_adaptor&&) = default;
338 
339  inner_allocator_type& inner_allocator() noexcept
340  { return _M_inner._M_get(this); }
341 
342  const inner_allocator_type& inner_allocator() const noexcept
343  { return _M_inner._M_get(this); }
344 
345  outer_allocator_type& outer_allocator() noexcept
346  { return static_cast<_OuterAlloc&>(*this); }
347 
348  const outer_allocator_type& outer_allocator() const noexcept
349  { return static_cast<const _OuterAlloc&>(*this); }
350 
351  pointer allocate(size_type __n)
352  { return __traits::allocate(outer_allocator(), __n); }
353 
354  pointer allocate(size_type __n, const_void_pointer __hint)
355  { return __traits::allocate(outer_allocator(), __n, __hint); }
356 
357  void deallocate(pointer __p, size_type __n)
358  { return __traits::deallocate(outer_allocator(), __p, __n); }
359 
360  size_type max_size() const
361  { return __traits::max_size(outer_allocator()); }
362 
363  template<typename _Tp, typename... _Args>
364  void construct(_Tp* __p, _Args&&... __args)
365  {
366  auto& __inner = inner_allocator();
367  auto __use_tag
368  = __use_alloc<_Tp, inner_allocator_type, _Args...>(__inner);
369  _M_construct(__use_tag, __p, std::forward<_Args>(__args)...);
370  }
371 
372  template<typename _T1, typename _T2, typename... _Args1,
373  typename... _Args2>
374  void
375  construct(pair<_T1, _T2>* __p, piecewise_construct_t,
376  tuple<_Args1...> __x, tuple<_Args2...> __y)
377  {
378  // _GLIBCXX_RESOLVE_LIB_DEFECTS
379  // 2203. wrong argument types for piecewise construction
380  auto& __inner = inner_allocator();
381  auto __x_use_tag
382  = __use_alloc<_T1, inner_allocator_type, _Args1...>(__inner);
383  auto __y_use_tag
384  = __use_alloc<_T2, inner_allocator_type, _Args2...>(__inner);
385  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
386  _O_traits::construct(__outermost(*this), __p, piecewise_construct,
387  _M_construct_p(__x_use_tag, __x),
388  _M_construct_p(__y_use_tag, __y));
389  }
390 
391  template<typename _T1, typename _T2>
392  void
393  construct(pair<_T1, _T2>* __p)
394  { construct(__p, piecewise_construct, tuple<>(), tuple<>()); }
395 
396  template<typename _T1, typename _T2, typename _Up, typename _Vp>
397  void
398  construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v)
399  {
400  construct(__p, piecewise_construct,
401  std::forward_as_tuple(std::forward<_Up>(__u)),
402  std::forward_as_tuple(std::forward<_Vp>(__v)));
403  }
404 
405  template<typename _T1, typename _T2, typename _Up, typename _Vp>
406  void
407  construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x)
408  {
409  construct(__p, piecewise_construct,
410  std::forward_as_tuple(__x.first),
411  std::forward_as_tuple(__x.second));
412  }
413 
414  template<typename _T1, typename _T2, typename _Up, typename _Vp>
415  void
416  construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x)
417  {
418  construct(__p, piecewise_construct,
419  std::forward_as_tuple(std::forward<_Up>(__x.first)),
420  std::forward_as_tuple(std::forward<_Vp>(__x.second)));
421  }
422 
423  template<typename _Tp>
424  void destroy(_Tp* __p)
425  {
426  typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits;
427  _O_traits::destroy(__outermost(*this), __p);
428  }
429 
430  scoped_allocator_adaptor
431  select_on_container_copy_construction() const
432  {
433  typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type
434  _Indices;
435  return scoped_allocator_adaptor(_M_tie(), _Indices());
436  }
437 
438  template <typename _OutA1, typename _OutA2, typename... _InA>
439  friend bool
440  operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
441  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept;
442 
443  private:
444  template<typename _Tuple>
445  _Tuple&&
446  _M_construct_p(__uses_alloc0, _Tuple& __t)
447  { return std::move(__t); }
448 
449  template<typename... _Args>
450  std::tuple<allocator_arg_t, inner_allocator_type&, _Args...>
451  _M_construct_p(__uses_alloc1_, std::tuple<_Args...>& __t)
452  {
453  typedef std::tuple<allocator_arg_t, inner_allocator_type&> _Tuple;
454  return std::tuple_cat(_Tuple(allocator_arg, inner_allocator()),
455  std::move(__t));
456  }
457 
458  template<typename... _Args>
459  std::tuple<_Args..., inner_allocator_type&>
460  _M_construct_p(__uses_alloc2_, std::tuple<_Args...>& __t)
461  {
462  typedef std::tuple<inner_allocator_type&> _Tuple;
463  return std::tuple_cat(std::move(__t), _Tuple(inner_allocator()));
464  }
465  };
466 
467  template <typename _OutA1, typename _OutA2, typename... _InA>
468  inline bool
469  operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
470  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
471  {
472  return __a.outer_allocator() == __b.outer_allocator()
473  && __a._M_inner == __b._M_inner;
474  }
475 
476  template <typename _OutA1, typename _OutA2, typename... _InA>
477  inline bool
478  operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a,
479  const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept
480  { return !(__a == __b); }
481 
482  /// @}
483 
484 _GLIBCXX_END_NAMESPACE_VERSION
485 } // namespace
486 
487 #endif // C++11
488 
489 #endif // _SCOPED_ALLOCATOR