1 // unique_ptr implementation -*- C++ -*-
2
3 // Copyright (C) 2008-2016 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /** @file bits/unique_ptr.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{memory}
28 */
29
30 #ifndef _UNIQUE_PTR_H
31 #define _UNIQUE_PTR_H 1
32
33 #include <bits/c++config.h>
34 #include <debug/assertions.h>
35 #include <type_traits>
36 #include <utility>
37 #include <tuple>
38
_GLIBCXX_VISIBILITY(default)39 namespace std _GLIBCXX_VISIBILITY(default)
40 {
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
42
43 /**
44 * @addtogroup pointer_abstractions
45 * @{
46 */
47
48 #if _GLIBCXX_USE_DEPRECATED
49 template<typename> class auto_ptr;
50 #endif
51
52 /// Primary template of default_delete, used by unique_ptr
53 template<typename _Tp>
54 struct default_delete
55 {
56 /// Default constructor
57 constexpr default_delete() noexcept = default;
58
59 /** @brief Converting constructor.
60 *
61 * Allows conversion from a deleter for arrays of another type, @p _Up,
62 * only if @p _Up* is convertible to @p _Tp*.
63 */
64 template<typename _Up, typename = typename
65 enable_if<is_convertible<_Up*, _Tp*>::value>::type>
66 default_delete(const default_delete<_Up>&) noexcept { }
67
68 /// Calls @c delete @p __ptr
69 void
70 operator()(_Tp* __ptr) const
71 {
72 static_assert(!is_void<_Tp>::value,
73 "can't delete pointer to incomplete type");
74 static_assert(sizeof(_Tp)>0,
75 "can't delete pointer to incomplete type");
76 delete __ptr;
77 }
78 };
79
80 // _GLIBCXX_RESOLVE_LIB_DEFECTS
81 // DR 740 - omit specialization for array objects with a compile time length
82 /// Specialization for arrays, default_delete.
83 template<typename _Tp>
84 struct default_delete<_Tp[]>
85 {
86 public:
87 /// Default constructor
88 constexpr default_delete() noexcept = default;
89
90 /** @brief Converting constructor.
91 *
92 * Allows conversion from a deleter for arrays of another type, such as
93 * a const-qualified version of @p _Tp.
94 *
95 * Conversions from types derived from @c _Tp are not allowed because
96 * it is unsafe to @c delete[] an array of derived types through a
97 * pointer to the base type.
98 */
99 template<typename _Up, typename = typename
100 enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type>
101 default_delete(const default_delete<_Up[]>&) noexcept { }
102
103 /// Calls @c delete[] @p __ptr
104 template<typename _Up>
105 typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
106 operator()(_Up* __ptr) const
107 {
108 static_assert(sizeof(_Tp)>0,
109 "can't delete pointer to incomplete type");
110 delete [] __ptr;
111 }
112 };
113
114 /// 20.7.1.2 unique_ptr for single objects.
115 template <typename _Tp, typename _Dp = default_delete<_Tp> >
116 class unique_ptr
117 {
118 // use SFINAE to determine whether _Del::pointer exists
119 class _Pointer
120 {
121 template<typename _Up>
122 static typename _Up::pointer __test(typename _Up::pointer*);
123
124 template<typename _Up>
125 static _Tp* __test(...);
126
127 typedef typename remove_reference<_Dp>::type _Del;
128
129 public:
130 typedef decltype(__test<_Del>(0)) type;
131 };
132
133 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
134 __tuple_type _M_t;
135
136 public:
137 typedef typename _Pointer::type pointer;
138 typedef _Tp element_type;
139 typedef _Dp deleter_type;
140
141
142 // helper template for detecting a safe conversion from another
143 // unique_ptr
144 template<typename _Up, typename _Ep>
145 using __safe_conversion_up = __and_<
146 is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
147 __not_<is_array<_Up>>,
148 __or_<__and_<is_reference<deleter_type>,
149 is_same<deleter_type, _Ep>>,
150 __and_<__not_<is_reference<deleter_type>>,
151 is_convertible<_Ep, deleter_type>>
152 >
153 >;
154
155 // Constructors.
156
157 /// Default constructor, creates a unique_ptr that owns nothing.
158 constexpr unique_ptr() noexcept
159 : _M_t()
160 { static_assert(!is_pointer<deleter_type>::value,
161 "constructed with null function pointer deleter"); }
162
163 /** Takes ownership of a pointer.
164 *
165 * @param __p A pointer to an object of @c element_type
166 *
167 * The deleter will be value-initialized.
168 */
169 explicit
170 unique_ptr(pointer __p) noexcept
171 : _M_t()
172 {
173 std::get<0>(_M_t) = __p;
174 static_assert(!is_pointer<deleter_type>::value,
175 "constructed with null function pointer deleter");
176 }
177
178 /** Takes ownership of a pointer.
179 *
180 * @param __p A pointer to an object of @c element_type
181 * @param __d A reference to a deleter.
182 *
183 * The deleter will be initialized with @p __d
184 */
185 unique_ptr(pointer __p,
186 typename conditional<is_reference<deleter_type>::value,
187 deleter_type, const deleter_type&>::type __d) noexcept
188 : _M_t(__p, __d) { }
189
190 /** Takes ownership of a pointer.
191 *
192 * @param __p A pointer to an object of @c element_type
193 * @param __d An rvalue reference to a deleter.
194 *
195 * The deleter will be initialized with @p std::move(__d)
196 */
197 unique_ptr(pointer __p,
198 typename remove_reference<deleter_type>::type&& __d) noexcept
199 : _M_t(std::move(__p), std::move(__d))
200 { static_assert(!std::is_reference<deleter_type>::value,
201 "rvalue deleter bound to reference"); }
202
203 /// Creates a unique_ptr that owns nothing.
204 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
205
206 // Move constructors.
207
208 /// Move constructor.
209 unique_ptr(unique_ptr&& __u) noexcept
210 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
211
212 /** @brief Converting constructor from another type
213 *
214 * Requires that the pointer owned by @p __u is convertible to the
215 * type of pointer owned by this object, @p __u does not own an array,
216 * and @p __u has a compatible deleter type.
217 */
218 template<typename _Up, typename _Ep, typename = _Require<
219 __safe_conversion_up<_Up, _Ep>,
220 typename conditional<is_reference<_Dp>::value,
221 is_same<_Ep, _Dp>,
222 is_convertible<_Ep, _Dp>>::type>>
223 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
224 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
225 { }
226
227 #if _GLIBCXX_USE_DEPRECATED
228 /// Converting constructor from @c auto_ptr
229 template<typename _Up, typename = _Require<
230 is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>>
231 unique_ptr(auto_ptr<_Up>&& __u) noexcept;
232 #endif
233
234 /// Destructor, invokes the deleter if the stored pointer is not null.
235 ~unique_ptr() noexcept
236 {
237 auto& __ptr = std::get<0>(_M_t);
238 if (__ptr != nullptr)
239 get_deleter()(__ptr);
240 __ptr = pointer();
241 }
242
243 // Assignment.
244
245 /** @brief Move assignment operator.
246 *
247 * @param __u The object to transfer ownership from.
248 *
249 * Invokes the deleter first if this object owns a pointer.
250 */
251 unique_ptr&
252 operator=(unique_ptr&& __u) noexcept
253 {
254 reset(__u.release());
255 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
256 return *this;
257 }
258
259 /** @brief Assignment from another type.
260 *
261 * @param __u The object to transfer ownership from, which owns a
262 * convertible pointer to a non-array object.
263 *
264 * Invokes the deleter first if this object owns a pointer.
265 */
266 template<typename _Up, typename _Ep>
267 typename enable_if< __and_<
268 __safe_conversion_up<_Up, _Ep>,
269 is_assignable<deleter_type&, _Ep&&>
270 >::value,
271 unique_ptr&>::type
272 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
273 {
274 reset(__u.release());
275 get_deleter() = std::forward<_Ep>(__u.get_deleter());
276 return *this;
277 }
278
279 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
280 unique_ptr&
281 operator=(nullptr_t) noexcept
282 {
283 reset();
284 return *this;
285 }
286
287 // Observers.
288
289 /// Dereference the stored pointer.
290 typename add_lvalue_reference<element_type>::type
291 operator*() const
292 {
293 __glibcxx_assert(get() != pointer());
294 return *get();
295 }
296
297 /// Return the stored pointer.
298 pointer
299 operator->() const noexcept
300 {
301 _GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
302 return get();
303 }
304
305 /// Return the stored pointer.
306 pointer
307 get() const noexcept
308 { return std::get<0>(_M_t); }
309
310 /// Return a reference to the stored deleter.
311 deleter_type&
312 get_deleter() noexcept
313 { return std::get<1>(_M_t); }
314
315 /// Return a reference to the stored deleter.
316 const deleter_type&
317 get_deleter() const noexcept
318 { return std::get<1>(_M_t); }
319
320 /// Return @c true if the stored pointer is not null.
321 explicit operator bool() const noexcept
322 { return get() == pointer() ? false : true; }
323
324 // Modifiers.
325
326 /// Release ownership of any stored pointer.
327 pointer
328 release() noexcept
329 {
330 pointer __p = get();
331 std::get<0>(_M_t) = pointer();
332 return __p;
333 }
334
335 /** @brief Replace the stored pointer.
336 *
337 * @param __p The new pointer to store.
338 *
339 * The deleter will be invoked if a pointer is already owned.
340 */
341 void
342 reset(pointer __p = pointer()) noexcept
343 {
344 using std::swap;
345 swap(std::get<0>(_M_t), __p);
346 if (__p != pointer())
347 get_deleter()(__p);
348 }
349
350 /// Exchange the pointer and deleter with another object.
351 void
352 swap(unique_ptr& __u) noexcept
353 {
354 using std::swap;
355 swap(_M_t, __u._M_t);
356 }
357
358 // Disable copy from lvalue.
359 unique_ptr(const unique_ptr&) = delete;
360 unique_ptr& operator=(const unique_ptr&) = delete;
361 };
362
363 /// 20.7.1.3 unique_ptr for array objects with a runtime length
364 // [unique.ptr.runtime]
365 // _GLIBCXX_RESOLVE_LIB_DEFECTS
366 // DR 740 - omit specialization for array objects with a compile time length
367 template<typename _Tp, typename _Dp>
368 class unique_ptr<_Tp[], _Dp>
369 {
370 // use SFINAE to determine whether _Del::pointer exists
371 class _Pointer
372 {
373 template<typename _Up>
374 static typename _Up::pointer __test(typename _Up::pointer*);
375
376 template<typename _Up>
377 static _Tp* __test(...);
378
379 typedef typename remove_reference<_Dp>::type _Del;
380
381 public:
382 typedef decltype(__test<_Del>(0)) type;
383 };
384
385 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
386 __tuple_type _M_t;
387
388 template<typename _Up>
389 using __remove_cv = typename remove_cv<_Up>::type;
390
391 // like is_base_of<_Tp, _Up> but false if unqualified types are the same
392 template<typename _Up>
393 using __is_derived_Tp
394 = __and_< is_base_of<_Tp, _Up>,
395 __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >;
396
397
398 public:
399 typedef typename _Pointer::type pointer;
400 typedef _Tp element_type;
401 typedef _Dp deleter_type;
402
403 // helper template for detecting a safe conversion from another
404 // unique_ptr
405 template<typename _Up, typename _Ep,
406 typename _Up_up = unique_ptr<_Up, _Ep>,
407 typename _Up_element_type = typename _Up_up::element_type>
408 using __safe_conversion_up = __and_<
409 is_array<_Up>,
410 is_same<pointer, element_type*>,
411 is_same<typename _Up_up::pointer, _Up_element_type*>,
412 is_convertible<_Up_element_type(*)[], element_type(*)[]>,
413 __or_<__and_<is_reference<deleter_type>, is_same<deleter_type, _Ep>>,
414 __and_<__not_<is_reference<deleter_type>>,
415 is_convertible<_Ep, deleter_type>>>
416 >;
417
418 // helper template for detecting a safe conversion from a raw pointer
419 template<typename _Up>
420 using __safe_conversion_raw = __and_<
421 __or_<__or_<is_same<_Up, pointer>,
422 is_same<_Up, nullptr_t>>,
423 __and_<is_pointer<_Up>,
424 is_same<pointer, element_type*>,
425 is_convertible<
426 typename remove_pointer<_Up>::type(*)[],
427 element_type(*)[]>
428 >
429 >
430 >;
431
432 // Constructors.
433
434 /// Default constructor, creates a unique_ptr that owns nothing.
435 constexpr unique_ptr() noexcept
436 : _M_t()
437 { static_assert(!std::is_pointer<deleter_type>::value,
438 "constructed with null function pointer deleter"); }
439
440 /** Takes ownership of a pointer.
441 *
442 * @param __p A pointer to an array of a type safely convertible
443 * to an array of @c element_type
444 *
445 * The deleter will be value-initialized.
446 */
447 template<typename _Up,
448 typename = typename enable_if<
449 __safe_conversion_raw<_Up>::value, bool>::type>
450 explicit
451 unique_ptr(_Up __p) noexcept
452 : _M_t(__p, deleter_type())
453 { static_assert(!is_pointer<deleter_type>::value,
454 "constructed with null function pointer deleter"); }
455
456 /** Takes ownership of a pointer.
457 *
458 * @param __p A pointer to an array of a type safely convertible
459 * to an array of @c element_type
460 * @param __d A reference to a deleter.
461 *
462 * The deleter will be initialized with @p __d
463 */
464 template<typename _Up,
465 typename = typename enable_if<
466 __safe_conversion_raw<_Up>::value, bool>::type>
467 unique_ptr(_Up __p,
468 typename conditional<is_reference<deleter_type>::value,
469 deleter_type, const deleter_type&>::type __d) noexcept
470 : _M_t(__p, __d) { }
471
472 /** Takes ownership of a pointer.
473 *
474 * @param __p A pointer to an array of a type safely convertible
475 * to an array of @c element_type
476 * @param __d A reference to a deleter.
477 *
478 * The deleter will be initialized with @p std::move(__d)
479 */
480 template<typename _Up,
481 typename = typename enable_if<
482 __safe_conversion_raw<_Up>::value, bool>::type>
483 unique_ptr(_Up __p, typename
484 remove_reference<deleter_type>::type&& __d) noexcept
485 : _M_t(std::move(__p), std::move(__d))
486 { static_assert(!is_reference<deleter_type>::value,
487 "rvalue deleter bound to reference"); }
488
489 /// Move constructor.
490 unique_ptr(unique_ptr&& __u) noexcept
491 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
492
493 /// Creates a unique_ptr that owns nothing.
494 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
495
496 template<typename _Up, typename _Ep,
497 typename = _Require<__safe_conversion_up<_Up, _Ep>>>
498 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
499 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
500 { }
501
502 /// Destructor, invokes the deleter if the stored pointer is not null.
503 ~unique_ptr()
504 {
505 auto& __ptr = std::get<0>(_M_t);
506 if (__ptr != nullptr)
507 get_deleter()(__ptr);
508 __ptr = pointer();
509 }
510
511 // Assignment.
512
513 /** @brief Move assignment operator.
514 *
515 * @param __u The object to transfer ownership from.
516 *
517 * Invokes the deleter first if this object owns a pointer.
518 */
519 unique_ptr&
520 operator=(unique_ptr&& __u) noexcept
521 {
522 reset(__u.release());
523 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
524 return *this;
525 }
526
527 /** @brief Assignment from another type.
528 *
529 * @param __u The object to transfer ownership from, which owns a
530 * convertible pointer to an array object.
531 *
532 * Invokes the deleter first if this object owns a pointer.
533 */
534 template<typename _Up, typename _Ep>
535 typename
536 enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
537 is_assignable<deleter_type&, _Ep&&>
538 >::value,
539 unique_ptr&>::type
540 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
541 {
542 reset(__u.release());
543 get_deleter() = std::forward<_Ep>(__u.get_deleter());
544 return *this;
545 }
546
547 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
548 unique_ptr&
549 operator=(nullptr_t) noexcept
550 {
551 reset();
552 return *this;
553 }
554
555 // Observers.
556
557 /// Access an element of owned array.
558 typename std::add_lvalue_reference<element_type>::type
559 operator[](size_t __i) const
560 {
561 __glibcxx_assert(get() != pointer());
562 return get()[__i];
563 }
564
565 /// Return the stored pointer.
566 pointer
567 get() const noexcept
568 { return std::get<0>(_M_t); }
569
570 /// Return a reference to the stored deleter.
571 deleter_type&
572 get_deleter() noexcept
573 { return std::get<1>(_M_t); }
574
575 /// Return a reference to the stored deleter.
576 const deleter_type&
577 get_deleter() const noexcept
578 { return std::get<1>(_M_t); }
579
580 /// Return @c true if the stored pointer is not null.
581 explicit operator bool() const noexcept
582 { return get() == pointer() ? false : true; }
583
584 // Modifiers.
585
586 /// Release ownership of any stored pointer.
587 pointer
588 release() noexcept
589 {
590 pointer __p = get();
591 std::get<0>(_M_t) = pointer();
592 return __p;
593 }
594
595 /** @brief Replace the stored pointer.
596 *
597 * @param __p The new pointer to store.
598 *
599 * The deleter will be invoked if a pointer is already owned.
600 */
601 template <typename _Up,
602 typename = _Require<
603 __or_<is_same<_Up, pointer>,
604 __and_<is_same<pointer, element_type*>,
605 is_pointer<_Up>,
606 is_convertible<
607 typename remove_pointer<_Up>::type(*)[],
608 element_type(*)[]
609 >
610 >
611 >
612 >>
613 void
614 reset(_Up __p) noexcept
615 {
616 pointer __ptr = __p;
617 using std::swap;
618 swap(std::get<0>(_M_t), __ptr);
619 if (__ptr != nullptr)
620 get_deleter()(__ptr);
621 }
622
623 void reset(nullptr_t = nullptr) noexcept
624 {
625 reset(pointer());
626 }
627
628 /// Exchange the pointer and deleter with another object.
629 void
630 swap(unique_ptr& __u) noexcept
631 {
632 using std::swap;
633 swap(_M_t, __u._M_t);
634 }
635
636 // Disable copy from lvalue.
637 unique_ptr(const unique_ptr&) = delete;
638 unique_ptr& operator=(const unique_ptr&) = delete;
639 };
640
641 template<typename _Tp, typename _Dp>
642 inline void
643 swap(unique_ptr<_Tp, _Dp>& __x,
644 unique_ptr<_Tp, _Dp>& __y) noexcept
645 { __x.swap(__y); }
646
647 template<typename _Tp, typename _Dp,
648 typename _Up, typename _Ep>
649 inline bool
650 operator==(const unique_ptr<_Tp, _Dp>& __x,
651 const unique_ptr<_Up, _Ep>& __y)
652 { return __x.get() == __y.get(); }
653
654 template<typename _Tp, typename _Dp>
655 inline bool
656 operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
657 { return !__x; }
658
659 template<typename _Tp, typename _Dp>
660 inline bool
661 operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
662 { return !__x; }
663
664 template<typename _Tp, typename _Dp,
665 typename _Up, typename _Ep>
666 inline bool
667 operator!=(const unique_ptr<_Tp, _Dp>& __x,
668 const unique_ptr<_Up, _Ep>& __y)
669 { return __x.get() != __y.get(); }
670
671 template<typename _Tp, typename _Dp>
672 inline bool
673 operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
674 { return (bool)__x; }
675
676 template<typename _Tp, typename _Dp>
677 inline bool
678 operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
679 { return (bool)__x; }
680
681 template<typename _Tp, typename _Dp,
682 typename _Up, typename _Ep>
683 inline bool
684 operator<(const unique_ptr<_Tp, _Dp>& __x,
685 const unique_ptr<_Up, _Ep>& __y)
686 {
687 typedef typename
688 std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
689 typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
690 return std::less<_CT>()(__x.get(), __y.get());
691 }
692
693 template<typename _Tp, typename _Dp>
694 inline bool
695 operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
696 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
697 nullptr); }
698
699 template<typename _Tp, typename _Dp>
700 inline bool
701 operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
702 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
703 __x.get()); }
704
705 template<typename _Tp, typename _Dp,
706 typename _Up, typename _Ep>
707 inline bool
708 operator<=(const unique_ptr<_Tp, _Dp>& __x,
709 const unique_ptr<_Up, _Ep>& __y)
710 { return !(__y < __x); }
711
712 template<typename _Tp, typename _Dp>
713 inline bool
714 operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
715 { return !(nullptr < __x); }
716
717 template<typename _Tp, typename _Dp>
718 inline bool
719 operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
720 { return !(__x < nullptr); }
721
722 template<typename _Tp, typename _Dp,
723 typename _Up, typename _Ep>
724 inline bool
725 operator>(const unique_ptr<_Tp, _Dp>& __x,
726 const unique_ptr<_Up, _Ep>& __y)
727 { return (__y < __x); }
728
729 template<typename _Tp, typename _Dp>
730 inline bool
731 operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
732 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
733 __x.get()); }
734
735 template<typename _Tp, typename _Dp>
736 inline bool
737 operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
738 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
739 nullptr); }
740
741 template<typename _Tp, typename _Dp,
742 typename _Up, typename _Ep>
743 inline bool
744 operator>=(const unique_ptr<_Tp, _Dp>& __x,
745 const unique_ptr<_Up, _Ep>& __y)
746 { return !(__x < __y); }
747
748 template<typename _Tp, typename _Dp>
749 inline bool
750 operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
751 { return !(__x < nullptr); }
752
753 template<typename _Tp, typename _Dp>
754 inline bool
755 operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
756 { return !(nullptr < __x); }
757
758 /// std::hash specialization for unique_ptr.
759 template<typename _Tp, typename _Dp>
760 struct hash<unique_ptr<_Tp, _Dp>>
761 : public __hash_base<size_t, unique_ptr<_Tp, _Dp>>
762 {
763 size_t
764 operator()(const unique_ptr<_Tp, _Dp>& __u) const noexcept
765 {
766 typedef unique_ptr<_Tp, _Dp> _UP;
767 return std::hash<typename _UP::pointer>()(__u.get());
768 }
769 };
770
771 #if __cplusplus > 201103L
772
773 #define __cpp_lib_make_unique 201304
774
775 template<typename _Tp>
776 struct _MakeUniq
777 { typedef unique_ptr<_Tp> __single_object; };
778
779 template<typename _Tp>
780 struct _MakeUniq<_Tp[]>
781 { typedef unique_ptr<_Tp[]> __array; };
782
783 template<typename _Tp, size_t _Bound>
784 struct _MakeUniq<_Tp[_Bound]>
785 { struct __invalid_type { }; };
786
787 /// std::make_unique for single objects
788 template<typename _Tp, typename... _Args>
789 inline typename _MakeUniq<_Tp>::__single_object
790 make_unique(_Args&&... __args)
791 { return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }
792
793 /// std::make_unique for arrays of unknown bound
794 template<typename _Tp>
795 inline typename _MakeUniq<_Tp>::__array
796 make_unique(size_t __num)
797 { return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }
798
799 /// Disable std::make_unique for arrays of known bound
800 template<typename _Tp, typename... _Args>
801 inline typename _MakeUniq<_Tp>::__invalid_type
802 make_unique(_Args&&...) = delete;
803 #endif
804
805 // @} group pointer_abstractions
806
807 _GLIBCXX_END_NAMESPACE_VERSION
808 } // namespace
809
810 #endif /* _UNIQUE_PTR_H */
811