1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP___NODE_HANDLE
11#define _LIBCPP___NODE_HANDLE
12
13#include <__config>
14#include <memory>
15#include <optional>
16
17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18#pragma GCC system_header
19#endif
20
21_LIBCPP_PUSH_MACROS
22#include <__undef_macros>
23
24_LIBCPP_BEGIN_NAMESPACE_STD
25
26#if _LIBCPP_STD_VER > 14
27
28// Specialized in __tree & __hash_table for their _NodeType.
29template <class _NodeType, class _Alloc>
30struct __generic_container_node_destructor;
31
32template <class _NodeType, class _Alloc,
33 template <class, class> class _MapOrSetSpecifics>
34class _LIBCPP_TEMPLATE_VIS __basic_node_handle
35 : public _MapOrSetSpecifics<
36 _NodeType,
37 __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>>
38{
39 template <class _Tp, class _Compare, class _Allocator>
40 friend class __tree;
41 template <class _Tp, class _Hash, class _Equal, class _Allocator>
42 friend class __hash_table;
43 friend struct _MapOrSetSpecifics<
44 _NodeType, __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>>;
45
46 typedef allocator_traits<_Alloc> __alloc_traits;
47 typedef typename __rebind_pointer<typename __alloc_traits::void_pointer,
48 _NodeType>::type
49 __node_pointer_type;
50
51public:
52 typedef _Alloc allocator_type;
53
54private:
55 __node_pointer_type __ptr_ = nullptr;
56 optional<allocator_type> __alloc_;
57
58 _LIBCPP_INLINE_VISIBILITY
59 void __release_ptr()
60 {
61 __ptr_ = nullptr;
62 __alloc_ = _VSTD::nullopt;
63 }
64
65 _LIBCPP_INLINE_VISIBILITY
66 void __destroy_node_pointer()
67 {
68 if (__ptr_ != nullptr)
69 {
70 typedef typename __allocator_traits_rebind<
71 allocator_type, _NodeType>::type __node_alloc_type;
72 __node_alloc_type __alloc(*__alloc_);
73 __generic_container_node_destructor<_NodeType, __node_alloc_type>(
74 __alloc, true)(__ptr_);
75 __ptr_ = nullptr;
76 }
77 }
78
79 _LIBCPP_INLINE_VISIBILITY
80 __basic_node_handle(__node_pointer_type __ptr,
81 allocator_type const& __alloc)
82 : __ptr_(__ptr), __alloc_(__alloc)
83 {
84 }
85
86public:
87 _LIBCPP_INLINE_VISIBILITY
88 __basic_node_handle() = default;
89
90 _LIBCPP_INLINE_VISIBILITY
91 __basic_node_handle(__basic_node_handle&& __other) noexcept
92 : __ptr_(__other.__ptr_),
93 __alloc_(_VSTD::move(__other.__alloc_))
94 {
95 __other.__ptr_ = nullptr;
96 __other.__alloc_ = _VSTD::nullopt;
97 }
98
99 _LIBCPP_INLINE_VISIBILITY
100 __basic_node_handle& operator=(__basic_node_handle&& __other)
101 {
102 _LIBCPP_ASSERT(
103 __alloc_ == _VSTD::nullopt ||
104 __alloc_traits::propagate_on_container_move_assignment::value ||
105 __alloc_ == __other.__alloc_,
106 "node_type with incompatible allocator passed to "
107 "node_type::operator=(node_type&&)");
108
109 __destroy_node_pointer();
110 __ptr_ = __other.__ptr_;
111
112 if (__alloc_traits::propagate_on_container_move_assignment::value ||
113 __alloc_ == _VSTD::nullopt)
114 __alloc_ = _VSTD::move(__other.__alloc_);
115
116 __other.__ptr_ = nullptr;
117 __other.__alloc_ = _VSTD::nullopt;
118
119 return *this;
120 }
121
122 _LIBCPP_INLINE_VISIBILITY
123 allocator_type get_allocator() const { return *__alloc_; }
124
125 _LIBCPP_INLINE_VISIBILITY
126 explicit operator bool() const { return __ptr_ != nullptr; }
127
128 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
129 bool empty() const { return __ptr_ == nullptr; }
130
131 _LIBCPP_INLINE_VISIBILITY
132 void swap(__basic_node_handle& __other) noexcept(
133 __alloc_traits::propagate_on_container_swap::value ||
134 __alloc_traits::is_always_equal::value)
135 {
136 using _VSTD::swap;
137 swap(__ptr_, __other.__ptr_);
138 if (__alloc_traits::propagate_on_container_swap::value ||
139 __alloc_ == _VSTD::nullopt || __other.__alloc_ == _VSTD::nullopt)
140 swap(__alloc_, __other.__alloc_);
141 }
142
143 _LIBCPP_INLINE_VISIBILITY
144 friend void swap(__basic_node_handle& __a, __basic_node_handle& __b)
145 noexcept(noexcept(__a.swap(__b))) { __a.swap(__b); }
146
147 _LIBCPP_INLINE_VISIBILITY
148 ~__basic_node_handle()
149 {
150 __destroy_node_pointer();
151 }
152};
153
154template <class _NodeType, class _Derived>
155struct __set_node_handle_specifics
156{
157 typedef typename _NodeType::__node_value_type value_type;
158
159 _LIBCPP_INLINE_VISIBILITY
160 value_type& value() const
161 {
162 return static_cast<_Derived const*>(this)->__ptr_->__value_;
163 }
164};
165
166template <class _NodeType, class _Derived>
167struct __map_node_handle_specifics
168{
169 typedef typename _NodeType::__node_value_type::key_type key_type;
170 typedef typename _NodeType::__node_value_type::mapped_type mapped_type;
171
172 _LIBCPP_INLINE_VISIBILITY
173 key_type& key() const
174 {
175 return static_cast<_Derived const*>(this)->
176 __ptr_->__value_.__ref().first;
177 }
178
179 _LIBCPP_INLINE_VISIBILITY
180 mapped_type& mapped() const
181 {
182 return static_cast<_Derived const*>(this)->
183 __ptr_->__value_.__ref().second;
184 }
185};
186
187template <class _NodeType, class _Alloc>
188using __set_node_handle =
189 __basic_node_handle< _NodeType, _Alloc, __set_node_handle_specifics>;
190
191template <class _NodeType, class _Alloc>
192using __map_node_handle =
193 __basic_node_handle< _NodeType, _Alloc, __map_node_handle_specifics>;
194
195template <class _Iterator, class _NodeType>
196struct _LIBCPP_TEMPLATE_VIS __insert_return_type
197{
198 _Iterator position;
199 bool inserted;
200 _NodeType node;
201};
202
203#endif // _LIBCPP_STD_VER > 14
204
205_LIBCPP_END_NAMESPACE_STD
206_LIBCPP_POP_MACROS
207
208#endif
209