xref: /freebsd/contrib/llvm-project/libcxx/include/__iterator/wrap_iter.h (revision 9f23cbd6cae82fd77edfad7173432fa8dccd0a95)
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 <__config>
14 #include <__debug>
15 #include <__iterator/iterator_traits.h>
16 #include <__memory/addressof.h>
17 #include <__memory/pointer_traits.h>
18 #include <__type_traits/enable_if.h>
19 #include <__type_traits/is_convertible.h>
20 
21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22 #  pragma GCC system_header
23 #endif
24 
25 _LIBCPP_BEGIN_NAMESPACE_STD
26 
27 template <class _Iter>
28 class __wrap_iter
29 {
30 public:
31     typedef _Iter                                                      iterator_type;
32     typedef typename iterator_traits<iterator_type>::value_type        value_type;
33     typedef typename iterator_traits<iterator_type>::difference_type   difference_type;
34     typedef typename iterator_traits<iterator_type>::pointer           pointer;
35     typedef typename iterator_traits<iterator_type>::reference         reference;
36     typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
37 #if _LIBCPP_STD_VER > 17
38     typedef contiguous_iterator_tag                                    iterator_concept;
39 #endif
40 
41 private:
42     iterator_type __i_;
43 public:
44     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter() _NOEXCEPT
45                 : __i_()
46     {
47         _VSTD::__debug_db_insert_i(this);
48     }
49     template <class _Up> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
50         __wrap_iter(const __wrap_iter<_Up>& __u,
51             typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = nullptr) _NOEXCEPT
52             : __i_(__u.base())
53     {
54 #ifdef _LIBCPP_ENABLE_DEBUG_MODE
55       if (!__libcpp_is_constant_evaluated())
56         __get_db()->__iterator_copy(this, _VSTD::addressof(__u));
57 #endif
58     }
59 #ifdef _LIBCPP_ENABLE_DEBUG_MODE
60     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
61     __wrap_iter(const __wrap_iter& __x)
62         : __i_(__x.base())
63     {
64       if (!__libcpp_is_constant_evaluated())
65         __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
66     }
67     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
68     __wrap_iter& operator=(const __wrap_iter& __x)
69     {
70         if (this != _VSTD::addressof(__x))
71         {
72             if (!__libcpp_is_constant_evaluated())
73                 __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
74             __i_ = __x.__i_;
75         }
76         return *this;
77     }
78     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
79     ~__wrap_iter()
80     {
81       if (!__libcpp_is_constant_evaluated())
82         __get_db()->__erase_i(this);
83     }
84 #endif
85     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT
86     {
87         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
88                              "Attempted to dereference a non-dereferenceable iterator");
89         return *__i_;
90     }
91     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT
92     {
93         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
94                              "Attempted to dereference a non-dereferenceable iterator");
95         return _VSTD::__to_address(__i_);
96     }
97     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator++() _NOEXCEPT
98     {
99         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
100                              "Attempted to increment a non-incrementable iterator");
101         ++__i_;
102         return *this;
103     }
104     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator++(int) _NOEXCEPT
105         {__wrap_iter __tmp(*this); ++(*this); return __tmp;}
106 
107     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator--() _NOEXCEPT
108     {
109         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__decrementable(this),
110                              "Attempted to decrement a non-decrementable iterator");
111         --__i_;
112         return *this;
113     }
114     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator--(int) _NOEXCEPT
115         {__wrap_iter __tmp(*this); --(*this); return __tmp;}
116     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT
117         {__wrap_iter __w(*this); __w += __n; return __w;}
118     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT
119     {
120         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__addable(this, __n),
121                              "Attempted to add/subtract an iterator outside its valid range");
122         __i_ += __n;
123         return *this;
124     }
125     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator- (difference_type __n) const _NOEXCEPT
126         {return *this + (-__n);}
127     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT
128         {*this += -__n; return *this;}
129     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference    operator[](difference_type __n) const _NOEXCEPT
130     {
131         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__subscriptable(this, __n),
132                              "Attempted to subscript an iterator outside its valid range");
133         return __i_[__n];
134     }
135 
136     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator_type base() const _NOEXCEPT {return __i_;}
137 
138 private:
139     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
140     explicit __wrap_iter(const void* __p, iterator_type __x) _NOEXCEPT : __i_(__x)
141     {
142         (void)__p;
143 #ifdef _LIBCPP_ENABLE_DEBUG_MODE
144       if (!__libcpp_is_constant_evaluated())
145         __get_db()->__insert_ic(this, __p);
146 #endif
147     }
148 
149     template <class _Up> friend class __wrap_iter;
150     template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
151     template <class _Tp, class _Alloc> friend class _LIBCPP_TEMPLATE_VIS vector;
152     template <class _Tp, size_t> friend class _LIBCPP_TEMPLATE_VIS span;
153 };
154 
155 template <class _Iter1>
156 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
157 bool operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
158 {
159     return __x.base() == __y.base();
160 }
161 
162 template <class _Iter1, class _Iter2>
163 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
164 bool operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
165 {
166     return __x.base() == __y.base();
167 }
168 
169 template <class _Iter1>
170 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
171 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
172 {
173     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
174                          "Attempted to compare incomparable iterators");
175     return __x.base() < __y.base();
176 }
177 
178 template <class _Iter1, class _Iter2>
179 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
180 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
181 {
182     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(&__x, &__y),
183                          "Attempted to compare incomparable iterators");
184     return __x.base() < __y.base();
185 }
186 
187 template <class _Iter1>
188 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
189 bool operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
190 {
191     return !(__x == __y);
192 }
193 
194 template <class _Iter1, class _Iter2>
195 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
196 bool operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
197 {
198     return !(__x == __y);
199 }
200 
201 template <class _Iter1>
202 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
203 bool operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
204 {
205     return __y < __x;
206 }
207 
208 template <class _Iter1, class _Iter2>
209 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
210 bool operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
211 {
212     return __y < __x;
213 }
214 
215 template <class _Iter1>
216 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
217 bool operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
218 {
219     return !(__x < __y);
220 }
221 
222 template <class _Iter1, class _Iter2>
223 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
224 bool operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
225 {
226     return !(__x < __y);
227 }
228 
229 template <class _Iter1>
230 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
231 bool operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
232 {
233     return !(__y < __x);
234 }
235 
236 template <class _Iter1, class _Iter2>
237 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
238 bool operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
239 {
240     return !(__y < __x);
241 }
242 
243 template <class _Iter1, class _Iter2>
244 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
245 #ifndef _LIBCPP_CXX03_LANG
246 auto operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
247     -> decltype(__x.base() - __y.base())
248 #else
249 typename __wrap_iter<_Iter1>::difference_type
250 operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
251 #endif // C++03
252 {
253     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
254                          "Attempted to subtract incompatible iterators");
255     return __x.base() - __y.base();
256 }
257 
258 template <class _Iter1>
259 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
260 __wrap_iter<_Iter1> operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT
261 {
262     __x += __n;
263     return __x;
264 }
265 
266 #if _LIBCPP_STD_VER <= 17
267 template <class _It>
268 struct __is_cpp17_contiguous_iterator<__wrap_iter<_It> > : true_type {};
269 #endif
270 
271 template <class _It>
272 struct _LIBCPP_TEMPLATE_VIS pointer_traits<__wrap_iter<_It> >
273 {
274     typedef __wrap_iter<_It> pointer;
275     typedef typename pointer_traits<_It>::element_type element_type;
276     typedef typename pointer_traits<_It>::difference_type difference_type;
277 
278     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
279     static element_type *to_address(pointer __w) _NOEXCEPT {
280         return _VSTD::__to_address(__w.base());
281     }
282 };
283 
284 _LIBCPP_END_NAMESPACE_STD
285 
286 #endif // _LIBCPP___ITERATOR_WRAP_ITER_H
287