1    	// Allocator traits -*- C++ -*-
2    	
3    	// Copyright (C) 2011-2017 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   	
41   	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
42   	{
43   	_GLIBCXX_BEGIN_NAMESPACE_VERSION
44   	
45   	/**
46   	 * @brief  Uniform interface to C++98 and C++11 allocators.
47   	 * @ingroup allocators
48   	*/
49   	template<typename _Alloc>
50   	  struct __alloc_traits
51   	#if __cplusplus >= 201103L
52   	  : std::allocator_traits<_Alloc>
53   	#endif
54   	  {
55   	    typedef _Alloc allocator_type;
56   	#if __cplusplus >= 201103L
57   	    typedef std::allocator_traits<_Alloc>           _Base_type;
58   	    typedef typename _Base_type::value_type         value_type;
59   	    typedef typename _Base_type::pointer            pointer;
60   	    typedef typename _Base_type::const_pointer      const_pointer;
61   	    typedef typename _Base_type::size_type          size_type;
62   	    typedef typename _Base_type::difference_type    difference_type;
63   	    // C++11 allocators do not define reference or const_reference
64   	    typedef value_type&                             reference;
65   	    typedef const value_type&                       const_reference;
66   	    using _Base_type::allocate;
67   	    using _Base_type::deallocate;
68   	    using _Base_type::construct;
69   	    using _Base_type::destroy;
70   	    using _Base_type::max_size;
71   	
72   	  private:
73   	    template<typename _Ptr>
74   	      using __is_custom_pointer
75   		= std::__and_<std::is_same<pointer, _Ptr>,
76   			      std::__not_<std::is_pointer<_Ptr>>>;
77   	
78   	  public:
79   	    // overload construct for non-standard pointer types
80   	    template<typename _Ptr, typename... _Args>
81   	      static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
82   	      construct(_Alloc& __a, _Ptr __p, _Args&&... __args)
83   	      {
84   		_Base_type::construct(__a, std::addressof(*__p),
85   				      std::forward<_Args>(__args)...);
86   	      }
87   	
88   	    // overload destroy for non-standard pointer types
89   	    template<typename _Ptr>
90   	      static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
91   	      destroy(_Alloc& __a, _Ptr __p)
92   	      { _Base_type::destroy(__a, std::addressof(*__p)); }
93   	
94   	    static _Alloc _S_select_on_copy(const _Alloc& __a)
95   	    { return _Base_type::select_on_container_copy_construction(__a); }
96   	
97   	    static void _S_on_swap(_Alloc& __a, _Alloc& __b)
98   	    { std::__alloc_on_swap(__a, __b); }
99   	
100  	    static constexpr bool _S_propagate_on_copy_assign()
101  	    { return _Base_type::propagate_on_container_copy_assignment::value; }
102  	
103  	    static constexpr bool _S_propagate_on_move_assign()
104  	    { return _Base_type::propagate_on_container_move_assignment::value; }
105  	
106  	    static constexpr bool _S_propagate_on_swap()
107  	    { return _Base_type::propagate_on_container_swap::value; }
108  	
109  	    static constexpr bool _S_always_equal()
110  	    { return _Base_type::is_always_equal::value; }
111  	
112  	    static constexpr bool _S_nothrow_move()
113  	    { return _S_propagate_on_move_assign() || _S_always_equal(); }
114  	
115  	    template<typename _Tp>
116  	      struct rebind
117  	      { typedef typename _Base_type::template rebind_alloc<_Tp> other; };
118  	#else
119  	
120  	    typedef typename _Alloc::pointer                pointer;
121  	    typedef typename _Alloc::const_pointer          const_pointer;
122  	    typedef typename _Alloc::value_type             value_type;
123  	    typedef typename _Alloc::reference              reference;
124  	    typedef typename _Alloc::const_reference        const_reference;
125  	    typedef typename _Alloc::size_type              size_type;
126  	    typedef typename _Alloc::difference_type        difference_type;
127  	
128  	    static pointer
129  	    allocate(_Alloc& __a, size_type __n)
130  	    { return __a.allocate(__n); }
131  	
132  	    static void deallocate(_Alloc& __a, pointer __p, size_type __n)
133  	    { __a.deallocate(__p, __n); }
134  	
135  	    template<typename _Tp>
136  	      static void construct(_Alloc& __a, pointer __p, const _Tp& __arg)
137  	      { __a.construct(__p, __arg); }
138  	
139  	    static void destroy(_Alloc& __a, pointer __p)
140  	    { __a.destroy(__p); }
141  	
142  	    static size_type max_size(const _Alloc& __a)
143  	    { return __a.max_size(); }
144  	
145  	    static const _Alloc& _S_select_on_copy(const _Alloc& __a) { return __a; }
146  	
147  	    static void _S_on_swap(_Alloc& __a, _Alloc& __b)
148  	    {
149  	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
150  	      // 431. Swapping containers with unequal allocators.
151  	      std::__alloc_swap<_Alloc>::_S_do_it(__a, __b);
152  	    }
153  	
154  	    template<typename _Tp>
155  	      struct rebind
156  	      { typedef typename _Alloc::template rebind<_Tp>::other other; };
157  	#endif
158  	  };
159  	
160  	_GLIBCXX_END_NAMESPACE_VERSION
161  	} // namespace __gnu_cxx
162  	
163  	#endif
164