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___ITERATOR_WRAP_ITER_H
11#define _LIBCPP___ITERATOR_WRAP_ITER_H
12
13#include <__compare/ordering.h>
14#include <__compare/three_way_comparable.h>
15#include <__config>
16#include <__iterator/iterator_traits.h>
17#include <__memory/addressof.h>
18#include <__memory/pointer_traits.h>
19#include <__type_traits/enable_if.h>
20#include <__type_traits/is_convertible.h>
21#include <cstddef>
22
23#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
24# pragma GCC system_header
25#endif
26
27_LIBCPP_BEGIN_NAMESPACE_STD
28
29template <class _Iter>
30class __wrap_iter {
31public:
32 typedef _Iter iterator_type;
33 typedef typename iterator_traits<iterator_type>::value_type value_type;
34 typedef typename iterator_traits<iterator_type>::difference_type difference_type;
35 typedef typename iterator_traits<iterator_type>::pointer pointer;
36 typedef typename iterator_traits<iterator_type>::reference reference;
37 typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
38#if _LIBCPP_STD_VER >= 20
39 typedef contiguous_iterator_tag iterator_concept;
40#endif
41
42private:
43 iterator_type __i_;
44
45public:
46 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter() _NOEXCEPT : __i_() {}
47 template <class _Up, __enable_if_t<is_convertible<_Up, iterator_type>::value, int> = 0>
48 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter(const __wrap_iter<_Up>& __u) _NOEXCEPT
49 : __i_(__u.base()) {}
50 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT { return *__i_; }
51 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT {
52 return std::__to_address(__i_);
53 }
54 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator++() _NOEXCEPT {
55 ++__i_;
56 return *this;
57 }
58 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator++(int) _NOEXCEPT {
59 __wrap_iter __tmp(*this);
60 ++(*this);
61 return __tmp;
62 }
63
64 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator--() _NOEXCEPT {
65 --__i_;
66 return *this;
67 }
68 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator--(int) _NOEXCEPT {
69 __wrap_iter __tmp(*this);
70 --(*this);
71 return __tmp;
72 }
73 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator+(difference_type __n) const _NOEXCEPT {
74 __wrap_iter __w(*this);
75 __w += __n;
76 return __w;
77 }
78 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT {
79 __i_ += __n;
80 return *this;
81 }
82 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter operator-(difference_type __n) const _NOEXCEPT {
83 return *this + (-__n);
84 }
85 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT {
86 *this += -__n;
87 return *this;
88 }
89 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator[](difference_type __n) const _NOEXCEPT {
90 return __i_[__n];
91 }
92
93 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator_type base() const _NOEXCEPT { return __i_; }
94
95private:
96 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __wrap_iter(iterator_type __x) _NOEXCEPT : __i_(__x) {}
97
98 template <class _Up>
99 friend class __wrap_iter;
100 template <class _CharT, class _Traits, class _Alloc>
101 friend class basic_string;
102 template <class _CharT, class _Traits>
103 friend class basic_string_view;
104 template <class _Tp, class _Alloc>
105 friend class _LIBCPP_TEMPLATE_VIS vector;
106 template <class _Tp, size_t>
107 friend class _LIBCPP_TEMPLATE_VIS span;
108 template <class _Tp, size_t _Size>
109 friend struct array;
110};
111
112template <class _Iter1>
113_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
114operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
115 return __x.base() == __y.base();
116}
117
118template <class _Iter1, class _Iter2>
119_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
120operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
121 return __x.base() == __y.base();
122}
123
124template <class _Iter1>
125_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
126operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
127 return __x.base() < __y.base();
128}
129
130template <class _Iter1, class _Iter2>
131_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool
132operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
133 return __x.base() < __y.base();
134}
135
136#if _LIBCPP_STD_VER <= 17
137template <class _Iter1>
138_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
139operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
140 return !(__x == __y);
141}
142
143template <class _Iter1, class _Iter2>
144_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
145operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
146 return !(__x == __y);
147}
148#endif
149
150// TODO(mordante) disable these overloads in the LLVM 20 release.
151template <class _Iter1>
152_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
153operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
154 return __y < __x;
155}
156
157template <class _Iter1, class _Iter2>
158_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
159operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
160 return __y < __x;
161}
162
163template <class _Iter1>
164_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
165operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
166 return !(__x < __y);
167}
168
169template <class _Iter1, class _Iter2>
170_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
171operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
172 return !(__x < __y);
173}
174
175template <class _Iter1>
176_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
177operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT {
178 return !(__y < __x);
179}
180
181template <class _Iter1, class _Iter2>
182_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool
183operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT {
184 return !(__y < __x);
185}
186
187#if _LIBCPP_STD_VER >= 20
188template <class _Iter1, class _Iter2>
189_LIBCPP_HIDE_FROM_ABI constexpr strong_ordering
190operator<=>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) noexcept {
191 if constexpr (three_way_comparable_with<_Iter1, _Iter2, strong_ordering>) {
192 return __x.base() <=> __y.base();
193 } else {
194 if (__x.base() < __y.base())
195 return strong_ordering::less;
196
197 if (__x.base() == __y.base())
198 return strong_ordering::equal;
199
200 return strong_ordering::greater;
201 }
202}
203#endif // _LIBCPP_STD_VER >= 20
204
205template <class _Iter1, class _Iter2>
206_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
207#ifndef _LIBCPP_CXX03_LANG
208 auto
209 operator-(const __wrap_iter<_Iter1>& __x,
210 const __wrap_iter<_Iter2>& __y) _NOEXCEPT->decltype(__x.base() - __y.base())
211#else
212typename __wrap_iter<_Iter1>::difference_type
213operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
214#endif // C++03
215{
216 return __x.base() - __y.base();
217}
218
219template <class _Iter1>
220_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter<_Iter1>
221operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT {
222 __x += __n;
223 return __x;
224}
225
226#if _LIBCPP_STD_VER <= 17
227template <class _It>
228struct __libcpp_is_contiguous_iterator<__wrap_iter<_It> > : true_type {};
229#endif
230
231template <class _It>
232struct _LIBCPP_TEMPLATE_VIS pointer_traits<__wrap_iter<_It> > {
233 typedef __wrap_iter<_It> pointer;
234 typedef typename pointer_traits<_It>::element_type element_type;
235 typedef typename pointer_traits<_It>::difference_type difference_type;
236
237 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static element_type* to_address(pointer __w) _NOEXCEPT {
238 return std::__to_address(__w.base());
239 }
240};
241
242_LIBCPP_END_NAMESPACE_STD
243
244#endif // _LIBCPP___ITERATOR_WRAP_ITER_H
245