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___MEMORY_UNIQUE_PTR_H
11 #define _LIBCPP___MEMORY_UNIQUE_PTR_H
12 
13 #include <__compare/compare_three_way.h>
14 #include <__compare/compare_three_way_result.h>
15 #include <__compare/three_way_comparable.h>
16 #include <__config>
17 #include <__functional/hash.h>
18 #include <__functional/operations.h>
19 #include <__memory/allocator_traits.h> // __pointer
20 #include <__memory/auto_ptr.h>
21 #include <__memory/compressed_pair.h>
22 #include <__type_traits/add_lvalue_reference.h>
23 #include <__type_traits/common_type.h>
24 #include <__type_traits/dependent_type.h>
25 #include <__type_traits/integral_constant.h>
26 #include <__type_traits/is_array.h>
27 #include <__type_traits/is_assignable.h>
28 #include <__type_traits/is_constructible.h>
29 #include <__type_traits/is_convertible.h>
30 #include <__type_traits/is_default_constructible.h>
31 #include <__type_traits/is_function.h>
32 #include <__type_traits/is_pointer.h>
33 #include <__type_traits/is_reference.h>
34 #include <__type_traits/is_same.h>
35 #include <__type_traits/is_swappable.h>
36 #include <__type_traits/is_void.h>
37 #include <__type_traits/remove_extent.h>
38 #include <__type_traits/type_identity.h>
39 #include <__utility/forward.h>
40 #include <__utility/move.h>
41 #include <cstddef>
42 
43 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
44 #  pragma GCC system_header
45 #endif
46 
47 _LIBCPP_BEGIN_NAMESPACE_STD
48 
49 template <class _Tp>
50 struct _LIBCPP_TEMPLATE_VIS default_delete {
51     static_assert(!is_function<_Tp>::value,
52                   "default_delete cannot be instantiated for function types");
53 #ifndef _LIBCPP_CXX03_LANG
54   _LIBCPP_INLINE_VISIBILITY constexpr default_delete() _NOEXCEPT = default;
55 #else
56   _LIBCPP_INLINE_VISIBILITY default_delete() {}
57 #endif
58   template <class _Up>
59   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 default_delete(
60       const default_delete<_Up>&, typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
61 
62   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 void operator()(_Tp* __ptr) const _NOEXCEPT {
63     static_assert(sizeof(_Tp) >= 0, "cannot delete an incomplete type");
64     static_assert(!is_void<_Tp>::value, "cannot delete an incomplete type");
65     delete __ptr;
66   }
67 };
68 
69 template <class _Tp>
70 struct _LIBCPP_TEMPLATE_VIS default_delete<_Tp[]> {
71 private:
72   template <class _Up>
73   struct _EnableIfConvertible
74       : enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value> {};
75 
76 public:
77 #ifndef _LIBCPP_CXX03_LANG
78   _LIBCPP_INLINE_VISIBILITY constexpr default_delete() _NOEXCEPT = default;
79 #else
80   _LIBCPP_INLINE_VISIBILITY default_delete() {}
81 #endif
82 
83   template <class _Up>
84   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
85   default_delete(const default_delete<_Up[]>&, typename _EnableIfConvertible<_Up>::type* = 0) _NOEXCEPT {}
86 
87   template <class _Up>
88   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 typename _EnableIfConvertible<_Up>::type
89   operator()(_Up* __ptr) const _NOEXCEPT {
90     static_assert(sizeof(_Up) >= 0, "cannot delete an incomplete type");
91     delete[] __ptr;
92   }
93 };
94 
95 template <class _Deleter>
96 struct __unique_ptr_deleter_sfinae {
97   static_assert(!is_reference<_Deleter>::value, "incorrect specialization");
98   typedef const _Deleter& __lval_ref_type;
99   typedef _Deleter&& __good_rval_ref_type;
100   typedef true_type __enable_rval_overload;
101 };
102 
103 template <class _Deleter>
104 struct __unique_ptr_deleter_sfinae<_Deleter const&> {
105   typedef const _Deleter& __lval_ref_type;
106   typedef const _Deleter&& __bad_rval_ref_type;
107   typedef false_type __enable_rval_overload;
108 };
109 
110 template <class _Deleter>
111 struct __unique_ptr_deleter_sfinae<_Deleter&> {
112   typedef _Deleter& __lval_ref_type;
113   typedef _Deleter&& __bad_rval_ref_type;
114   typedef false_type __enable_rval_overload;
115 };
116 
117 #if defined(_LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI)
118 #  define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI __attribute__((trivial_abi))
119 #else
120 #  define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI
121 #endif
122 
123 template <class _Tp, class _Dp = default_delete<_Tp> >
124 class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr {
125 public:
126   typedef _Tp element_type;
127   typedef _Dp deleter_type;
128   typedef _LIBCPP_NODEBUG typename __pointer<_Tp, deleter_type>::type pointer;
129 
130   static_assert(!is_rvalue_reference<deleter_type>::value,
131                 "the specified deleter type cannot be an rvalue reference");
132 
133 private:
134   __compressed_pair<pointer, deleter_type> __ptr_;
135 
136   struct __nat { int __for_bool_; };
137 
138   typedef _LIBCPP_NODEBUG __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
139 
140   template <bool _Dummy>
141   using _LValRefType _LIBCPP_NODEBUG =
142       typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
143 
144   template <bool _Dummy>
145   using _GoodRValRefType _LIBCPP_NODEBUG =
146       typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
147 
148   template <bool _Dummy>
149   using _BadRValRefType _LIBCPP_NODEBUG =
150       typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
151 
152   template <bool _Dummy, class _Deleter = typename __dependent_type<
153                              __type_identity<deleter_type>, _Dummy>::type>
154   using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG =
155       typename enable_if<is_default_constructible<_Deleter>::value &&
156                          !is_pointer<_Deleter>::value>::type;
157 
158   template <class _ArgType>
159   using _EnableIfDeleterConstructible _LIBCPP_NODEBUG =
160       typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
161 
162   template <class _UPtr, class _Up>
163   using _EnableIfMoveConvertible _LIBCPP_NODEBUG = typename enable_if<
164       is_convertible<typename _UPtr::pointer, pointer>::value &&
165       !is_array<_Up>::value
166   >::type;
167 
168   template <class _UDel>
169   using _EnableIfDeleterConvertible _LIBCPP_NODEBUG = typename enable_if<
170       (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
171       (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
172     >::type;
173 
174   template <class _UDel>
175   using _EnableIfDeleterAssignable = typename enable_if<
176       is_assignable<_Dp&, _UDel&&>::value
177     >::type;
178 
179 public:
180   template <bool _Dummy = true,
181             class = _EnableIfDeleterDefaultConstructible<_Dummy> >
182   _LIBCPP_INLINE_VISIBILITY
183   _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
184 
185   template <bool _Dummy = true,
186             class = _EnableIfDeleterDefaultConstructible<_Dummy> >
187   _LIBCPP_INLINE_VISIBILITY
188   _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
189 
190   template <bool _Dummy = true, class = _EnableIfDeleterDefaultConstructible<_Dummy> >
191   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit unique_ptr(pointer __p) _NOEXCEPT
192       : __ptr_(__p, __value_init_tag()) {}
193 
194   template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
195   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(pointer __p, _LValRefType<_Dummy> __d) _NOEXCEPT
196       : __ptr_(__p, __d) {}
197 
198   template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
199   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
200   unique_ptr(pointer __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT : __ptr_(__p, _VSTD::move(__d)) {
201     static_assert(!is_reference<deleter_type>::value,
202                   "rvalue deleter bound to reference");
203   }
204 
205   template <bool _Dummy = true,
206             class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> > >
207   _LIBCPP_INLINE_VISIBILITY
208   unique_ptr(pointer __p, _BadRValRefType<_Dummy> __d) = delete;
209 
210   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr&& __u) _NOEXCEPT
211       : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
212 
213   template <class _Up,
214             class _Ep,
215             class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
216             class = _EnableIfDeleterConvertible<_Ep> >
217   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
218       : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
219 
220 #if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
221   template <class _Up>
222   _LIBCPP_INLINE_VISIBILITY
223   unique_ptr(auto_ptr<_Up>&& __p,
224              typename enable_if<is_convertible<_Up*, _Tp*>::value &&
225                                     is_same<_Dp, default_delete<_Tp> >::value,
226                                 __nat>::type = __nat()) _NOEXCEPT
227       : __ptr_(__p.release(), __value_init_tag()) {}
228 #endif
229 
230   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
231     reset(__u.release());
232     __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
233     return *this;
234   }
235 
236   template <class _Up,
237             class _Ep,
238             class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
239             class = _EnableIfDeleterAssignable<_Ep> >
240   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
241     reset(__u.release());
242     __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
243     return *this;
244   }
245 
246 #if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
247   template <class _Up>
248   _LIBCPP_INLINE_VISIBILITY
249       typename enable_if<is_convertible<_Up*, _Tp*>::value &&
250                              is_same<_Dp, default_delete<_Tp> >::value,
251                          unique_ptr&>::type
252       operator=(auto_ptr<_Up> __p) {
253     reset(__p.release());
254     return *this;
255   }
256 #endif
257 
258 #ifdef _LIBCPP_CXX03_LANG
259   unique_ptr(unique_ptr const&) = delete;
260   unique_ptr& operator=(unique_ptr const&) = delete;
261 #endif
262 
263   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 ~unique_ptr() { reset(); }
264 
265   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(nullptr_t) _NOEXCEPT {
266     reset();
267     return *this;
268   }
269 
270   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 __add_lvalue_reference_t<_Tp> operator*() const {
271     return *__ptr_.first();
272   }
273   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer operator->() const _NOEXCEPT {
274     return __ptr_.first();
275   }
276   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer get() const _NOEXCEPT { return __ptr_.first(); }
277   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 deleter_type& get_deleter() _NOEXCEPT {
278     return __ptr_.second();
279   }
280   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 const deleter_type& get_deleter() const _NOEXCEPT {
281     return __ptr_.second();
282   }
283   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit operator bool() const _NOEXCEPT {
284     return __ptr_.first() != nullptr;
285   }
286 
287   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer release() _NOEXCEPT {
288     pointer __t = __ptr_.first();
289     __ptr_.first() = pointer();
290     return __t;
291   }
292 
293   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 void reset(pointer __p = pointer()) _NOEXCEPT {
294     pointer __tmp = __ptr_.first();
295     __ptr_.first() = __p;
296     if (__tmp)
297       __ptr_.second()(__tmp);
298   }
299 
300   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 void swap(unique_ptr& __u) _NOEXCEPT {
301     __ptr_.swap(__u.__ptr_);
302   }
303 };
304 
305 
306 template <class _Tp, class _Dp>
307 class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
308 public:
309   typedef _Tp element_type;
310   typedef _Dp deleter_type;
311   typedef typename __pointer<_Tp, deleter_type>::type pointer;
312 
313 private:
314   __compressed_pair<pointer, deleter_type> __ptr_;
315 
316   template <class _From>
317   struct _CheckArrayPointerConversion : is_same<_From, pointer> {};
318 
319   template <class _FromElem>
320   struct _CheckArrayPointerConversion<_FromElem*>
321       : integral_constant<bool,
322           is_same<_FromElem*, pointer>::value ||
323             (is_same<pointer, element_type*>::value &&
324              is_convertible<_FromElem(*)[], element_type(*)[]>::value)
325       >
326   {};
327 
328   typedef __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
329 
330   template <bool _Dummy>
331   using _LValRefType _LIBCPP_NODEBUG =
332       typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
333 
334   template <bool _Dummy>
335   using _GoodRValRefType _LIBCPP_NODEBUG =
336       typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
337 
338   template <bool _Dummy>
339   using _BadRValRefType _LIBCPP_NODEBUG =
340       typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
341 
342   template <bool _Dummy, class _Deleter = typename __dependent_type<
343                              __type_identity<deleter_type>, _Dummy>::type>
344   using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG =
345       typename enable_if<is_default_constructible<_Deleter>::value &&
346                          !is_pointer<_Deleter>::value>::type;
347 
348   template <class _ArgType>
349   using _EnableIfDeleterConstructible _LIBCPP_NODEBUG =
350       typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
351 
352   template <class _Pp>
353   using _EnableIfPointerConvertible _LIBCPP_NODEBUG = typename enable_if<
354       _CheckArrayPointerConversion<_Pp>::value
355   >::type;
356 
357   template <class _UPtr, class _Up,
358         class _ElemT = typename _UPtr::element_type>
359   using _EnableIfMoveConvertible _LIBCPP_NODEBUG = typename enable_if<
360       is_array<_Up>::value &&
361       is_same<pointer, element_type*>::value &&
362       is_same<typename _UPtr::pointer, _ElemT*>::value &&
363       is_convertible<_ElemT(*)[], element_type(*)[]>::value
364     >::type;
365 
366   template <class _UDel>
367   using _EnableIfDeleterConvertible _LIBCPP_NODEBUG = typename enable_if<
368       (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
369       (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
370     >::type;
371 
372   template <class _UDel>
373   using _EnableIfDeleterAssignable _LIBCPP_NODEBUG = typename enable_if<
374       is_assignable<_Dp&, _UDel&&>::value
375     >::type;
376 
377 public:
378   template <bool _Dummy = true,
379             class = _EnableIfDeleterDefaultConstructible<_Dummy> >
380   _LIBCPP_INLINE_VISIBILITY
381   _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
382 
383   template <bool _Dummy = true,
384             class = _EnableIfDeleterDefaultConstructible<_Dummy> >
385   _LIBCPP_INLINE_VISIBILITY
386   _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT : __ptr_(__value_init_tag(), __value_init_tag()) {}
387 
388   template <class _Pp,
389             bool _Dummy = true,
390             class       = _EnableIfDeleterDefaultConstructible<_Dummy>,
391             class       = _EnableIfPointerConvertible<_Pp> >
392   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit unique_ptr(_Pp __p) _NOEXCEPT
393       : __ptr_(__p, __value_init_tag()) {}
394 
395   template <class _Pp,
396             bool _Dummy = true,
397             class       = _EnableIfDeleterConstructible<_LValRefType<_Dummy> >,
398             class       = _EnableIfPointerConvertible<_Pp> >
399   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(_Pp __p, _LValRefType<_Dummy> __d) _NOEXCEPT
400       : __ptr_(__p, __d) {}
401 
402   template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
403   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(nullptr_t, _LValRefType<_Dummy> __d) _NOEXCEPT
404       : __ptr_(nullptr, __d) {}
405 
406   template <class _Pp,
407             bool _Dummy = true,
408             class       = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> >,
409             class       = _EnableIfPointerConvertible<_Pp> >
410   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(_Pp __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
411       : __ptr_(__p, _VSTD::move(__d)) {
412     static_assert(!is_reference<deleter_type>::value,
413                   "rvalue deleter bound to reference");
414   }
415 
416   template <bool _Dummy = true, class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
417   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(nullptr_t, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
418       : __ptr_(nullptr, _VSTD::move(__d)) {
419     static_assert(!is_reference<deleter_type>::value,
420                   "rvalue deleter bound to reference");
421   }
422 
423   template <class _Pp, bool _Dummy = true,
424             class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> >,
425             class = _EnableIfPointerConvertible<_Pp> >
426   _LIBCPP_INLINE_VISIBILITY
427   unique_ptr(_Pp __p, _BadRValRefType<_Dummy> __d) = delete;
428 
429   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr&& __u) _NOEXCEPT
430       : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
431 
432   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
433     reset(__u.release());
434     __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
435     return *this;
436   }
437 
438   template <class _Up,
439             class _Ep,
440             class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
441             class = _EnableIfDeleterConvertible<_Ep> >
442   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
443       : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
444 
445   template <class _Up,
446             class _Ep,
447             class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
448             class = _EnableIfDeleterAssignable<_Ep> >
449   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
450     reset(__u.release());
451     __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
452     return *this;
453   }
454 
455 #ifdef _LIBCPP_CXX03_LANG
456   unique_ptr(unique_ptr const&) = delete;
457   unique_ptr& operator=(unique_ptr const&) = delete;
458 #endif
459 public:
460   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 ~unique_ptr() { reset(); }
461 
462   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 unique_ptr& operator=(nullptr_t) _NOEXCEPT {
463     reset();
464     return *this;
465   }
466 
467   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 __add_lvalue_reference_t<_Tp>
468   operator[](size_t __i) const {
469     return __ptr_.first()[__i];
470   }
471   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer get() const _NOEXCEPT { return __ptr_.first(); }
472 
473   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 deleter_type& get_deleter() _NOEXCEPT {
474     return __ptr_.second();
475   }
476 
477   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 const deleter_type& get_deleter() const _NOEXCEPT {
478     return __ptr_.second();
479   }
480   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 explicit operator bool() const _NOEXCEPT {
481     return __ptr_.first() != nullptr;
482   }
483 
484   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 pointer release() _NOEXCEPT {
485     pointer __t = __ptr_.first();
486     __ptr_.first() = pointer();
487     return __t;
488   }
489 
490   template <class _Pp>
491   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
492       typename enable_if< _CheckArrayPointerConversion<_Pp>::value >::type
493       reset(_Pp __p) _NOEXCEPT {
494     pointer __tmp = __ptr_.first();
495     __ptr_.first() = __p;
496     if (__tmp)
497       __ptr_.second()(__tmp);
498   }
499 
500   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 void reset(nullptr_t = nullptr) _NOEXCEPT {
501     pointer __tmp = __ptr_.first();
502     __ptr_.first() = nullptr;
503     if (__tmp)
504       __ptr_.second()(__tmp);
505   }
506 
507   _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 void swap(unique_ptr& __u) _NOEXCEPT {
508     __ptr_.swap(__u.__ptr_);
509   }
510 };
511 
512 template <class _Tp, class _Dp>
513 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
514     typename enable_if< __is_swappable<_Dp>::value, void >::type
515     swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {
516   __x.swap(__y);
517 }
518 
519 template <class _T1, class _D1, class _T2, class _D2>
520 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
521 operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
522   return __x.get() == __y.get();
523 }
524 
525 #if _LIBCPP_STD_VER <= 17
526 template <class _T1, class _D1, class _T2, class _D2>
527 inline _LIBCPP_INLINE_VISIBILITY
528 bool
529 operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
530 #endif
531 
532 template <class _T1, class _D1, class _T2, class _D2>
533 inline _LIBCPP_INLINE_VISIBILITY
534 bool
535 operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
536 {
537     typedef typename unique_ptr<_T1, _D1>::pointer _P1;
538     typedef typename unique_ptr<_T2, _D2>::pointer _P2;
539     typedef typename common_type<_P1, _P2>::type _Vp;
540     return less<_Vp>()(__x.get(), __y.get());
541 }
542 
543 template <class _T1, class _D1, class _T2, class _D2>
544 inline _LIBCPP_INLINE_VISIBILITY
545 bool
546 operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
547 
548 template <class _T1, class _D1, class _T2, class _D2>
549 inline _LIBCPP_INLINE_VISIBILITY
550 bool
551 operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
552 
553 template <class _T1, class _D1, class _T2, class _D2>
554 inline _LIBCPP_INLINE_VISIBILITY
555 bool
556 operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
557 
558 
559 #if _LIBCPP_STD_VER > 17
560 template <class _T1, class _D1, class _T2, class _D2>
561 requires three_way_comparable_with<typename unique_ptr<_T1, _D1>::pointer,
562                                    typename unique_ptr<_T2, _D2>::pointer>
563 _LIBCPP_HIDE_FROM_ABI
564 compare_three_way_result_t<typename unique_ptr<_T1, _D1>::pointer,
565                            typename unique_ptr<_T2, _D2>::pointer>
566 operator<=>(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {
567    return compare_three_way()(__x.get(), __y.get());
568 }
569 #endif
570 
571 template <class _T1, class _D1>
572 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
573 operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT {
574   return !__x;
575 }
576 
577 #if _LIBCPP_STD_VER <= 17
578 template <class _T1, class _D1>
579 inline _LIBCPP_INLINE_VISIBILITY
580 bool
581 operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
582 {
583     return !__x;
584 }
585 
586 template <class _T1, class _D1>
587 inline _LIBCPP_INLINE_VISIBILITY
588 bool
589 operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
590 {
591     return static_cast<bool>(__x);
592 }
593 
594 template <class _T1, class _D1>
595 inline _LIBCPP_INLINE_VISIBILITY
596 bool
597 operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
598 {
599     return static_cast<bool>(__x);
600 }
601 #endif // _LIBCPP_STD_VER <= 17
602 
603 template <class _T1, class _D1>
604 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
605 operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
606   typedef typename unique_ptr<_T1, _D1>::pointer _P1;
607   return less<_P1>()(__x.get(), nullptr);
608 }
609 
610 template <class _T1, class _D1>
611 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
612 operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
613   typedef typename unique_ptr<_T1, _D1>::pointer _P1;
614   return less<_P1>()(nullptr, __x.get());
615 }
616 
617 template <class _T1, class _D1>
618 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
619 operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
620   return nullptr < __x;
621 }
622 
623 template <class _T1, class _D1>
624 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
625 operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
626   return __x < nullptr;
627 }
628 
629 template <class _T1, class _D1>
630 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
631 operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
632   return !(nullptr < __x);
633 }
634 
635 template <class _T1, class _D1>
636 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
637 operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
638   return !(__x < nullptr);
639 }
640 
641 template <class _T1, class _D1>
642 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
643 operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
644   return !(__x < nullptr);
645 }
646 
647 template <class _T1, class _D1>
648 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool
649 operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x) {
650   return !(nullptr < __x);
651 }
652 
653 #if _LIBCPP_STD_VER > 17
654 template <class _T1, class _D1>
655   requires three_way_comparable<
656       typename unique_ptr<_T1, _D1>::pointer> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23
657       compare_three_way_result_t<typename unique_ptr<_T1, _D1>::pointer>
658 operator<=>(const unique_ptr<_T1, _D1>& __x, nullptr_t) {
659    return compare_three_way()(__x.get(), static_cast<typename unique_ptr<_T1, _D1>::pointer>(nullptr));
660 }
661 #endif
662 
663 #if _LIBCPP_STD_VER > 11
664 
665 template<class _Tp>
666 struct __unique_if
667 {
668     typedef unique_ptr<_Tp> __unique_single;
669 };
670 
671 template<class _Tp>
672 struct __unique_if<_Tp[]>
673 {
674     typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
675 };
676 
677 template<class _Tp, size_t _Np>
678 struct __unique_if<_Tp[_Np]>
679 {
680     typedef void __unique_array_known_bound;
681 };
682 
683 template <class _Tp, class... _Args>
684 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_single
685 make_unique(_Args&&... __args) {
686   return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
687 }
688 
689 template <class _Tp>
690 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_array_unknown_bound
691 make_unique(size_t __n) {
692   typedef __remove_extent_t<_Tp> _Up;
693   return unique_ptr<_Tp>(new _Up[__n]());
694 }
695 
696 template<class _Tp, class... _Args>
697     typename __unique_if<_Tp>::__unique_array_known_bound
698     make_unique(_Args&&...) = delete;
699 
700 #endif // _LIBCPP_STD_VER > 11
701 
702 #if _LIBCPP_STD_VER >= 20
703 
704 template <class _Tp>
705 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_single
706 make_unique_for_overwrite() {
707   return unique_ptr<_Tp>(new _Tp);
708 }
709 
710 template <class _Tp>
711 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 typename __unique_if<_Tp>::__unique_array_unknown_bound
712 make_unique_for_overwrite(size_t __n) {
713   return unique_ptr<_Tp>(new __remove_extent_t<_Tp>[__n]);
714 }
715 
716 template<class _Tp, class... _Args>
717 typename __unique_if<_Tp>::__unique_array_known_bound make_unique_for_overwrite(_Args&&...) = delete;
718 
719 #endif // _LIBCPP_STD_VER >= 20
720 
721 template <class _Tp> struct _LIBCPP_TEMPLATE_VIS hash;
722 
723 template <class _Tp, class _Dp>
724 #ifdef _LIBCPP_CXX03_LANG
725 struct _LIBCPP_TEMPLATE_VIS hash<unique_ptr<_Tp, _Dp> >
726 #else
727 struct _LIBCPP_TEMPLATE_VIS hash<__enable_hash_helper<
728     unique_ptr<_Tp, _Dp>, typename unique_ptr<_Tp, _Dp>::pointer> >
729 #endif
730 {
731 #if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_BINDER_TYPEDEFS)
732     _LIBCPP_DEPRECATED_IN_CXX17 typedef unique_ptr<_Tp, _Dp> argument_type;
733     _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t               result_type;
734 #endif
735 
736     _LIBCPP_INLINE_VISIBILITY
737     size_t operator()(const unique_ptr<_Tp, _Dp>& __ptr) const
738     {
739         typedef typename unique_ptr<_Tp, _Dp>::pointer pointer;
740         return hash<pointer>()(__ptr.get());
741     }
742 };
743 
744 _LIBCPP_END_NAMESPACE_STD
745 
746 #endif // _LIBCPP___MEMORY_UNIQUE_PTR_H
747