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/* 14 15template<unspecified> 16class node-handle { 17public: 18 using value_type = see below; // not present for map containers 19 using key_type = see below; // not present for set containers 20 using mapped_type = see below; // not present for set containers 21 using allocator_type = see below; 22 23private: 24 using container_node_type = unspecified; // exposition only 25 using ator_traits = allocator_traits<allocator_type>; // exposition only 26 27 typename ator_traits::template 28 rebind_traits<container_node_type>::pointer ptr_; // exposition only 29 optional<allocator_type> alloc_; // exposition only 30 31public: 32 // [container.node.cons], constructors, copy, and assignment 33 constexpr node-handle() noexcept : ptr_(), alloc_() {} 34 node-handle(node-handle&&) noexcept; 35 node-handle& operator=(node-handle&&); 36 37 // [container.node.dtor], destructor 38 ~node-handle(); 39 40 // [container.node.observers], observers 41 value_type& value() const; // not present for map containers 42 key_type& key() const; // not present for set containers 43 mapped_type& mapped() const; // not present for set containers 44 45 allocator_type get_allocator() const; 46 explicit operator bool() const noexcept; 47 [[nodiscard]] bool empty() const noexcept; // nodiscard since C++20 48 49 // [container.node.modifiers], modifiers 50 void swap(node-handle&) 51 noexcept(ator_traits::propagate_on_container_swap::value || 52 ator_traits::is_always_equal::value); 53 54 friend void swap(node-handle& x, node-handle& y) noexcept(noexcept(x.swap(y))) { 55 x.swap(y); 56 } 57}; 58 59*/ 60 61#include <__assert> 62#include <__config> 63#include <__memory/allocator_traits.h> 64#include <__memory/pointer_traits.h> 65#include <optional> 66 67#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 68# pragma GCC system_header 69#endif 70 71_LIBCPP_PUSH_MACROS 72#include <__undef_macros> 73 74_LIBCPP_BEGIN_NAMESPACE_STD 75 76#if _LIBCPP_STD_VER >= 17 77 78// Specialized in __tree & __hash_table for their _NodeType. 79template <class _NodeType, class _Alloc> 80struct __generic_container_node_destructor; 81 82template <class _NodeType, class _Alloc, template <class, class> class _MapOrSetSpecifics> 83class _LIBCPP_TEMPLATE_VIS __basic_node_handle 84 : public _MapOrSetSpecifics< _NodeType, __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>> { 85 template <class _Tp, class _Compare, class _Allocator> 86 friend class __tree; 87 template <class _Tp, class _Hash, class _Equal, class _Allocator> 88 friend class __hash_table; 89 friend struct _MapOrSetSpecifics< _NodeType, __basic_node_handle<_NodeType, _Alloc, _MapOrSetSpecifics>>; 90 91 typedef allocator_traits<_Alloc> __alloc_traits; 92 typedef __rebind_pointer_t<typename __alloc_traits::void_pointer, _NodeType> __node_pointer_type; 93 94public: 95 typedef _Alloc allocator_type; 96 97private: 98 __node_pointer_type __ptr_ = nullptr; 99 optional<allocator_type> __alloc_; 100 101 _LIBCPP_HIDE_FROM_ABI void __release_ptr() { 102 __ptr_ = nullptr; 103 __alloc_ = std::nullopt; 104 } 105 106 _LIBCPP_HIDE_FROM_ABI void __destroy_node_pointer() { 107 if (__ptr_ != nullptr) { 108 typedef typename __allocator_traits_rebind< allocator_type, _NodeType>::type __node_alloc_type; 109 __node_alloc_type __alloc(*__alloc_); 110 __generic_container_node_destructor<_NodeType, __node_alloc_type>(__alloc, true)(__ptr_); 111 __ptr_ = nullptr; 112 } 113 } 114 115 _LIBCPP_HIDE_FROM_ABI __basic_node_handle(__node_pointer_type __ptr, allocator_type const& __alloc) 116 : __ptr_(__ptr), __alloc_(__alloc) {} 117 118public: 119 _LIBCPP_HIDE_FROM_ABI __basic_node_handle() = default; 120 121 _LIBCPP_HIDE_FROM_ABI __basic_node_handle(__basic_node_handle&& __other) noexcept 122 : __ptr_(__other.__ptr_), __alloc_(std::move(__other.__alloc_)) { 123 __other.__ptr_ = nullptr; 124 __other.__alloc_ = std::nullopt; 125 } 126 127 _LIBCPP_HIDE_FROM_ABI __basic_node_handle& operator=(__basic_node_handle&& __other) { 128 _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR( 129 __alloc_ == std::nullopt || __alloc_traits::propagate_on_container_move_assignment::value || 130 __alloc_ == __other.__alloc_, 131 "node_type with incompatible allocator passed to " 132 "node_type::operator=(node_type&&)"); 133 134 __destroy_node_pointer(); 135 __ptr_ = __other.__ptr_; 136 137 if (__alloc_traits::propagate_on_container_move_assignment::value || __alloc_ == std::nullopt) 138 __alloc_ = std::move(__other.__alloc_); 139 140 __other.__ptr_ = nullptr; 141 __other.__alloc_ = std::nullopt; 142 143 return *this; 144 } 145 146 _LIBCPP_HIDE_FROM_ABI allocator_type get_allocator() const { return *__alloc_; } 147 148 _LIBCPP_HIDE_FROM_ABI explicit operator bool() const { return __ptr_ != nullptr; } 149 150 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_HIDE_FROM_ABI bool empty() const { return __ptr_ == nullptr; } 151 152 _LIBCPP_HIDE_FROM_ABI void swap(__basic_node_handle& __other) noexcept( 153 __alloc_traits::propagate_on_container_swap::value || __alloc_traits::is_always_equal::value) { 154 using std::swap; 155 swap(__ptr_, __other.__ptr_); 156 if (__alloc_traits::propagate_on_container_swap::value || __alloc_ == std::nullopt || 157 __other.__alloc_ == std::nullopt) 158 swap(__alloc_, __other.__alloc_); 159 } 160 161 _LIBCPP_HIDE_FROM_ABI friend void 162 swap(__basic_node_handle& __a, __basic_node_handle& __b) noexcept(noexcept(__a.swap(__b))) { 163 __a.swap(__b); 164 } 165 166 _LIBCPP_HIDE_FROM_ABI ~__basic_node_handle() { __destroy_node_pointer(); } 167}; 168 169template <class _NodeType, class _Derived> 170struct __set_node_handle_specifics { 171 typedef typename _NodeType::__node_value_type value_type; 172 173 _LIBCPP_HIDE_FROM_ABI value_type& value() const { return static_cast<_Derived const*>(this)->__ptr_->__get_value(); } 174}; 175 176template <class _NodeType, class _Derived> 177struct __map_node_handle_specifics { 178 typedef typename _NodeType::__node_value_type::key_type key_type; 179 typedef typename _NodeType::__node_value_type::mapped_type mapped_type; 180 181 _LIBCPP_HIDE_FROM_ABI key_type& key() const { 182 return static_cast<_Derived const*>(this)->__ptr_->__get_value().__ref().first; 183 } 184 185 _LIBCPP_HIDE_FROM_ABI mapped_type& mapped() const { 186 return static_cast<_Derived const*>(this)->__ptr_->__get_value().__ref().second; 187 } 188}; 189 190template <class _NodeType, class _Alloc> 191using __set_node_handle = __basic_node_handle< _NodeType, _Alloc, __set_node_handle_specifics>; 192 193template <class _NodeType, class _Alloc> 194using __map_node_handle = __basic_node_handle< _NodeType, _Alloc, __map_node_handle_specifics>; 195 196template <class _Iterator, class _NodeType> 197struct _LIBCPP_TEMPLATE_VIS __insert_return_type { 198 _Iterator position; 199 bool inserted; 200 _NodeType node; 201}; 202 203#endif // _LIBCPP_STD_VER >= 17 204 205_LIBCPP_END_NAMESPACE_STD 206 207_LIBCPP_POP_MACROS 208 209#endif // _LIBCPP___NODE_HANDLE 210