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>
19 
20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21 #pragma GCC system_header
22 #endif
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 template <class _Iter>
27 class __wrap_iter
28 {
29 public:
30     typedef _Iter                                                      iterator_type;
31     typedef typename iterator_traits<iterator_type>::value_type        value_type;
32     typedef typename iterator_traits<iterator_type>::difference_type   difference_type;
33     typedef typename iterator_traits<iterator_type>::pointer           pointer;
34     typedef typename iterator_traits<iterator_type>::reference         reference;
35     typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
36 #if _LIBCPP_STD_VER > 17
37     typedef contiguous_iterator_tag                                    iterator_concept;
38 #endif
39 
40 private:
41     iterator_type __i;
42 public:
43     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter() _NOEXCEPT
44                 : __i()
45     {
46 #if _LIBCPP_DEBUG_LEVEL == 2
47       if (!__libcpp_is_constant_evaluated())
48         __get_db()->__insert_i(this);
49 #endif
50     }
51     template <class _Up> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
52         __wrap_iter(const __wrap_iter<_Up>& __u,
53             typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = nullptr) _NOEXCEPT
54             : __i(__u.base())
55     {
56 #if _LIBCPP_DEBUG_LEVEL == 2
57       if (!__libcpp_is_constant_evaluated())
58         __get_db()->__iterator_copy(this, _VSTD::addressof(__u));
59 #endif
60     }
61 #if _LIBCPP_DEBUG_LEVEL == 2
62     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
63     __wrap_iter(const __wrap_iter& __x)
64         : __i(__x.base())
65     {
66       if (!__libcpp_is_constant_evaluated())
67         __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
68     }
69     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
70     __wrap_iter& operator=(const __wrap_iter& __x)
71     {
72         if (this != _VSTD::addressof(__x))
73         {
74             if (!__libcpp_is_constant_evaluated())
75                 __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
76             __i = __x.__i;
77         }
78         return *this;
79     }
80     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
81     ~__wrap_iter()
82     {
83       if (!__libcpp_is_constant_evaluated())
84         __get_db()->__erase_i(this);
85     }
86 #endif
87     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 reference operator*() const _NOEXCEPT
88     {
89         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
90                              "Attempted to dereference a non-dereferenceable iterator");
91         return *__i;
92     }
93     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 pointer operator->() const _NOEXCEPT
94     {
95         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
96                              "Attempted to dereference a non-dereferenceable iterator");
97         return _VSTD::__to_address(__i);
98     }
99     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter& operator++() _NOEXCEPT
100     {
101         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
102                              "Attempted to increment a non-incrementable iterator");
103         ++__i;
104         return *this;
105     }
106     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter  operator++(int) _NOEXCEPT
107         {__wrap_iter __tmp(*this); ++(*this); return __tmp;}
108 
109     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter& operator--() _NOEXCEPT
110     {
111         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__decrementable(this),
112                              "Attempted to decrement a non-decrementable iterator");
113         --__i;
114         return *this;
115     }
116     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter  operator--(int) _NOEXCEPT
117         {__wrap_iter __tmp(*this); --(*this); return __tmp;}
118     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT
119         {__wrap_iter __w(*this); __w += __n; return __w;}
120     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT
121     {
122         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__addable(this, __n),
123                              "Attempted to add/subtract an iterator outside its valid range");
124         __i += __n;
125         return *this;
126     }
127     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter  operator- (difference_type __n) const _NOEXCEPT
128         {return *this + (-__n);}
129     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT
130         {*this += -__n; return *this;}
131     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 reference    operator[](difference_type __n) const _NOEXCEPT
132     {
133         _LIBCPP_DEBUG_ASSERT(__get_const_db()->__subscriptable(this, __n),
134                              "Attempted to subscript an iterator outside its valid range");
135         return __i[__n];
136     }
137 
138     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 iterator_type base() const _NOEXCEPT {return __i;}
139 
140 private:
141 #if _LIBCPP_DEBUG_LEVEL == 2
142     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter(const void* __p, iterator_type __x) : __i(__x)
143     {
144       if (!__libcpp_is_constant_evaluated())
145         __get_db()->__insert_ic(this, __p);
146     }
147 #else
148     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 __wrap_iter(iterator_type __x) _NOEXCEPT : __i(__x) {}
149 #endif
150 
151     template <class _Up> friend class __wrap_iter;
152     template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
153     template <class _Tp, class _Alloc> friend class _LIBCPP_TEMPLATE_VIS vector;
154     template <class _Tp, size_t> friend class _LIBCPP_TEMPLATE_VIS span;
155 };
156 
157 template <class _Iter1>
158 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
159 bool operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
160 {
161     return __x.base() == __y.base();
162 }
163 
164 template <class _Iter1, class _Iter2>
165 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
166 bool operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
167 {
168     return __x.base() == __y.base();
169 }
170 
171 template <class _Iter1>
172 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
173 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
174 {
175     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
176                          "Attempted to compare incomparable iterators");
177     return __x.base() < __y.base();
178 }
179 
180 template <class _Iter1, class _Iter2>
181 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
182 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
183 {
184     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(&__x, &__y),
185                          "Attempted to compare incomparable iterators");
186     return __x.base() < __y.base();
187 }
188 
189 template <class _Iter1>
190 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
191 bool operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
192 {
193     return !(__x == __y);
194 }
195 
196 template <class _Iter1, class _Iter2>
197 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
198 bool operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
199 {
200     return !(__x == __y);
201 }
202 
203 template <class _Iter1>
204 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
205 bool operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
206 {
207     return __y < __x;
208 }
209 
210 template <class _Iter1, class _Iter2>
211 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
212 bool operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
213 {
214     return __y < __x;
215 }
216 
217 template <class _Iter1>
218 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
219 bool operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
220 {
221     return !(__x < __y);
222 }
223 
224 template <class _Iter1, class _Iter2>
225 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
226 bool operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
227 {
228     return !(__x < __y);
229 }
230 
231 template <class _Iter1>
232 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
233 bool operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
234 {
235     return !(__y < __x);
236 }
237 
238 template <class _Iter1, class _Iter2>
239 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
240 bool operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
241 {
242     return !(__y < __x);
243 }
244 
245 template <class _Iter1, class _Iter2>
246 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
247 #ifndef _LIBCPP_CXX03_LANG
248 auto operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
249     -> decltype(__x.base() - __y.base())
250 #else
251 typename __wrap_iter<_Iter1>::difference_type
252 operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
253 #endif // C++03
254 {
255     _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
256                          "Attempted to subtract incompatible iterators");
257     return __x.base() - __y.base();
258 }
259 
260 template <class _Iter1>
261 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
262 __wrap_iter<_Iter1> operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT
263 {
264     __x += __n;
265     return __x;
266 }
267 
268 #if _LIBCPP_STD_VER <= 17
269 template <class _It>
270 struct __is_cpp17_contiguous_iterator<__wrap_iter<_It> > : true_type {};
271 #endif
272 
273 template <class _It>
274 struct _LIBCPP_TEMPLATE_VIS pointer_traits<__wrap_iter<_It> >
275 {
276     typedef __wrap_iter<_It> pointer;
277     typedef typename pointer_traits<_It>::element_type element_type;
278     typedef typename pointer_traits<_It>::difference_type difference_type;
279 
280     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
281     static element_type *to_address(pointer __w) _NOEXCEPT {
282         return _VSTD::__to_address(__w.base());
283     }
284 };
285 
286 _LIBCPP_END_NAMESPACE_STD
287 
288 #endif // _LIBCPP___ITERATOR_WRAP_ITER_H
289