1// Allocator traits -*- C++ -*-
2
3// Copyright (C) 2011-2013 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 ext/alloc_traits.h
26 *  This file is a GNU extension to the Standard C++ Library.
27 */
28
29#ifndef _EXT_ALLOC_TRAITS_H
30#define _EXT_ALLOC_TRAITS_H 1
31
32#pragma GCC system_header
33
34#if __cplusplus >= 201103L
35# include <bits/move.h>
36# include <bits/alloc_traits.h>
37#else
38# include <bits/allocator.h>  // for __alloc_swap
39#endif
40
41namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
42{
43_GLIBCXX_BEGIN_NAMESPACE_VERSION
44
45#if __cplusplus >= 201103L
46  template<typename _Alloc>
47    struct __allocator_always_compares_equal
48    { static const bool value = false; };
49
50  template<typename _Alloc>
51    const bool __allocator_always_compares_equal<_Alloc>::value;
52
53  template<typename _Tp>
54    struct __allocator_always_compares_equal<std::allocator<_Tp>>
55    { static const bool value = true; };
56
57  template<typename _Tp>
58    const bool __allocator_always_compares_equal<std::allocator<_Tp>>::value;
59
60  template<typename, typename> struct array_allocator;
61
62  template<typename _Tp, typename _Array>
63    struct __allocator_always_compares_equal<array_allocator<_Tp, _Array>>
64    { static const bool value = true; };
65
66  template<typename _Tp, typename _Array>
67    const bool
68    __allocator_always_compares_equal<array_allocator<_Tp, _Array>>::value;
69
70  template<typename> struct bitmap_allocator;
71
72  template<typename _Tp>
73    struct __allocator_always_compares_equal<bitmap_allocator<_Tp>>
74    { static const bool value = true; };
75
76  template<typename _Tp>
77    const bool __allocator_always_compares_equal<bitmap_allocator<_Tp>>::value;
78
79  template<typename> struct malloc_allocator;
80
81  template<typename _Tp>
82    struct __allocator_always_compares_equal<malloc_allocator<_Tp>>
83    { static const bool value = true; };
84
85  template<typename _Tp>
86    const bool __allocator_always_compares_equal<malloc_allocator<_Tp>>::value;
87
88  template<typename> struct mt_allocator;
89
90  template<typename _Tp>
91    struct __allocator_always_compares_equal<mt_allocator<_Tp>>
92    { static const bool value = true; };
93
94  template<typename _Tp>
95    const bool __allocator_always_compares_equal<mt_allocator<_Tp>>::value;
96
97  template<typename> struct new_allocator;
98
99  template<typename _Tp>
100    struct __allocator_always_compares_equal<new_allocator<_Tp>>
101    { static const bool value = true; };
102
103  template<typename _Tp>
104    const bool __allocator_always_compares_equal<new_allocator<_Tp>>::value;
105
106  template<typename> struct pool_allocator;
107
108  template<typename _Tp>
109    struct __allocator_always_compares_equal<pool_allocator<_Tp>>
110    { static const bool value = true; };
111
112  template<typename _Tp>
113    const bool __allocator_always_compares_equal<pool_allocator<_Tp>>::value;
114#endif
115
116/**
117 * @brief  Uniform interface to C++98 and C++0x allocators.
118 * @ingroup allocators
119*/
120template<typename _Alloc>
121  struct __alloc_traits
122#if __cplusplus >= 201103L
123  : std::allocator_traits<_Alloc>
124#endif
125  {
126    typedef _Alloc allocator_type;
127#if __cplusplus >= 201103L
128    typedef std::allocator_traits<_Alloc>           _Base_type;
129    typedef typename _Base_type::value_type         value_type;
130    typedef typename _Base_type::pointer            pointer;
131    typedef typename _Base_type::const_pointer      const_pointer;
132    typedef typename _Base_type::size_type          size_type;
133    typedef typename _Base_type::difference_type    difference_type;
134    // C++0x allocators do not define reference or const_reference
135    typedef value_type&                             reference;
136    typedef const value_type&                       const_reference;
137    using _Base_type::allocate;
138    using _Base_type::deallocate;
139    using _Base_type::construct;
140    using _Base_type::destroy;
141    using _Base_type::max_size;
142
143  private:
144    template<typename _Ptr>
145      struct __is_custom_pointer
146      : std::integral_constant<bool, std::is_same<pointer, _Ptr>::value
147                                     && !std::is_pointer<_Ptr>::value>
148      { };
149
150  public:
151    // overload construct for non-standard pointer types
152    template<typename _Ptr, typename... _Args>
153      static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
154      construct(_Alloc& __a, _Ptr __p, _Args&&... __args)
155      {
156	_Base_type::construct(__a, std::addressof(*__p),
157			      std::forward<_Args>(__args)...);
158      }
159
160    // overload destroy for non-standard pointer types
161    template<typename _Ptr>
162      static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
163      destroy(_Alloc& __a, _Ptr __p)
164      { _Base_type::destroy(__a, std::addressof(*__p)); }
165
166    static _Alloc _S_select_on_copy(const _Alloc& __a)
167    { return _Base_type::select_on_container_copy_construction(__a); }
168
169    static void _S_on_swap(_Alloc& __a, _Alloc& __b)
170    { std::__alloc_on_swap(__a, __b); }
171
172    static constexpr bool _S_propagate_on_copy_assign()
173    { return _Base_type::propagate_on_container_copy_assignment::value; }
174
175    static constexpr bool _S_propagate_on_move_assign()
176    { return _Base_type::propagate_on_container_move_assignment::value; }
177
178    static constexpr bool _S_propagate_on_swap()
179    { return _Base_type::propagate_on_container_swap::value; }
180
181    static constexpr bool _S_always_equal()
182    { return __allocator_always_compares_equal<_Alloc>::value; }
183
184    static constexpr bool _S_nothrow_move()
185    { return _S_propagate_on_move_assign() || _S_always_equal(); }
186
187    static constexpr bool _S_nothrow_swap()
188    {
189      using std::swap;
190      return !_S_propagate_on_swap()
191       	|| noexcept(swap(std::declval<_Alloc&>(), std::declval<_Alloc&>()));
192    }
193
194    template<typename _Tp>
195      struct rebind
196      { typedef typename _Base_type::template rebind_alloc<_Tp> other; };
197#else
198
199    typedef typename _Alloc::pointer                pointer;
200    typedef typename _Alloc::const_pointer          const_pointer;
201    typedef typename _Alloc::value_type             value_type;
202    typedef typename _Alloc::reference              reference;
203    typedef typename _Alloc::const_reference        const_reference;
204    typedef typename _Alloc::size_type              size_type;
205    typedef typename _Alloc::difference_type        difference_type;
206
207    static pointer
208    allocate(_Alloc& __a, size_type __n)
209    { return __a.allocate(__n); }
210
211    static void deallocate(_Alloc& __a, pointer __p, size_type __n)
212    { __a.deallocate(__p, __n); }
213
214    template<typename _Tp>
215      static void construct(_Alloc& __a, pointer __p, const _Tp& __arg)
216      { __a.construct(__p, __arg); }
217
218    static void destroy(_Alloc& __a, pointer __p)
219    { __a.destroy(__p); }
220
221    static size_type max_size(const _Alloc& __a)
222    { return __a.max_size(); }
223
224    static const _Alloc& _S_select_on_copy(const _Alloc& __a) { return __a; }
225
226    static void _S_on_swap(_Alloc& __a, _Alloc& __b)
227    {
228      // _GLIBCXX_RESOLVE_LIB_DEFECTS
229      // 431. Swapping containers with unequal allocators.
230      std::__alloc_swap<_Alloc>::_S_do_it(__a, __b);
231    }
232
233    template<typename _Tp>
234      struct rebind
235      { typedef typename _Alloc::template rebind<_Tp>::other other; };
236#endif
237  };
238
239_GLIBCXX_END_NAMESPACE_VERSION
240} // namespace std
241
242#endif
243