/
function.h
2811 lines (2466 loc) · 80.9 KB
/
function.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___FUNCTIONAL_FUNCTION_H
#define _LIBCPP___FUNCTIONAL_FUNCTION_H
#include <__config>
#include <__debug>
#include <__functional/binary_function.h>
#include <__functional/invoke.h>
#include <__functional/unary_function.h>
#include <__iterator/iterator_traits.h>
#include <__memory/addressof.h>
#include <__memory/allocator_traits.h>
#include <__memory/compressed_pair.h>
#include <__memory/shared_ptr.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <exception>
#include <memory> // TODO: replace with <__memory/__builtin_new_allocator.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
// bad_function_call
class _LIBCPP_EXCEPTION_ABI bad_function_call
: public exception
{
public:
// Note that when a key function is not used, every translation unit that uses
// bad_function_call will end up containing a weak definition of the vtable and
// typeinfo.
#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
virtual ~bad_function_call() _NOEXCEPT;
#else
virtual ~bad_function_call() _NOEXCEPT {}
#endif
#ifdef _LIBCPP_ABI_BAD_FUNCTION_CALL_GOOD_WHAT_MESSAGE
virtual const char* what() const _NOEXCEPT;
#endif
};
_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
void __throw_bad_function_call()
{
#ifndef _LIBCPP_NO_EXCEPTIONS
throw bad_function_call();
#else
_VSTD::abort();
#endif
}
#if defined(_LIBCPP_CXX03_LANG) && !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS) && __has_attribute(deprecated)
# define _LIBCPP_DEPRECATED_CXX03_FUNCTION \
__attribute__((deprecated("Using std::function in C++03 is not supported anymore. Please upgrade to C++11 or later, or use a different type")))
#else
# define _LIBCPP_DEPRECATED_CXX03_FUNCTION /* nothing */
#endif
template<class _Fp> class _LIBCPP_DEPRECATED_CXX03_FUNCTION _LIBCPP_TEMPLATE_VIS function; // undefined
namespace __function
{
template<class _Rp>
struct __maybe_derive_from_unary_function
{
};
template<class _Rp, class _A1>
struct __maybe_derive_from_unary_function<_Rp(_A1)>
: public unary_function<_A1, _Rp>
{
};
template<class _Rp>
struct __maybe_derive_from_binary_function
{
};
template<class _Rp, class _A1, class _A2>
struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)>
: public binary_function<_A1, _A2, _Rp>
{
};
template <class _Fp>
_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Fp const&) { return true; }
template <class _Fp>
_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Fp* __ptr) { return __ptr; }
template <class _Ret, class _Class>
_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Ret _Class::*__ptr) { return __ptr; }
template <class _Fp>
_LIBCPP_INLINE_VISIBILITY
bool __not_null(function<_Fp> const& __f) { return !!__f; }
#ifdef _LIBCPP_HAS_EXTENSION_BLOCKS
template <class _Rp, class ..._Args>
_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Rp (^__p)(_Args...)) { return __p; }
#endif
} // namespace __function
#ifndef _LIBCPP_CXX03_LANG
namespace __function {
// __alloc_func holds a functor and an allocator.
template <class _Fp, class _Ap, class _FB> class __alloc_func;
template <class _Fp, class _FB>
class __default_alloc_func;
template <class _Fp, class _Ap, class _Rp, class... _ArgTypes>
class __alloc_func<_Fp, _Ap, _Rp(_ArgTypes...)>
{
__compressed_pair<_Fp, _Ap> __f_;
public:
typedef _LIBCPP_NODEBUG _Fp _Target;
typedef _LIBCPP_NODEBUG _Ap _Alloc;
_LIBCPP_INLINE_VISIBILITY
const _Target& __target() const { return __f_.first(); }
// WIN32 APIs may define __allocator, so use __get_allocator instead.
_LIBCPP_INLINE_VISIBILITY
const _Alloc& __get_allocator() const { return __f_.second(); }
_LIBCPP_INLINE_VISIBILITY
explicit __alloc_func(_Target&& __f)
: __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
_VSTD::forward_as_tuple())
{
}
_LIBCPP_INLINE_VISIBILITY
explicit __alloc_func(const _Target& __f, const _Alloc& __a)
: __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
_VSTD::forward_as_tuple(__a))
{
}
_LIBCPP_INLINE_VISIBILITY
explicit __alloc_func(const _Target& __f, _Alloc&& __a)
: __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
_VSTD::forward_as_tuple(_VSTD::move(__a)))
{
}
_LIBCPP_INLINE_VISIBILITY
explicit __alloc_func(_Target&& __f, _Alloc&& __a)
: __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
_VSTD::forward_as_tuple(_VSTD::move(__a)))
{
}
_LIBCPP_INLINE_VISIBILITY
_Rp operator()(_ArgTypes&&... __arg)
{
typedef __invoke_void_return_wrapper<_Rp> _Invoker;
return _Invoker::__call(__f_.first(),
_VSTD::forward<_ArgTypes>(__arg)...);
}
_LIBCPP_INLINE_VISIBILITY
__alloc_func* __clone() const
{
typedef allocator_traits<_Alloc> __alloc_traits;
typedef
typename __rebind_alloc_helper<__alloc_traits, __alloc_func>::type
_AA;
_AA __a(__f_.second());
typedef __allocator_destructor<_AA> _Dp;
unique_ptr<__alloc_func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
::new ((void*)__hold.get()) __alloc_func(__f_.first(), _Alloc(__a));
return __hold.release();
}
_LIBCPP_INLINE_VISIBILITY
void destroy() _NOEXCEPT { __f_.~__compressed_pair<_Target, _Alloc>(); }
static void __destroy_and_delete(__alloc_func* __f) {
typedef allocator_traits<_Alloc> __alloc_traits;
typedef typename __rebind_alloc_helper<__alloc_traits, __alloc_func>::type
_FunAlloc;
_FunAlloc __a(__f->__get_allocator());
__f->destroy();
__a.deallocate(__f, 1);
}
};
template <class _Fp, class _Rp, class... _ArgTypes>
class __default_alloc_func<_Fp, _Rp(_ArgTypes...)> {
_Fp __f_;
public:
typedef _LIBCPP_NODEBUG _Fp _Target;
_LIBCPP_INLINE_VISIBILITY
const _Target& __target() const { return __f_; }
_LIBCPP_INLINE_VISIBILITY
explicit __default_alloc_func(_Target&& __f) : __f_(_VSTD::move(__f)) {}
_LIBCPP_INLINE_VISIBILITY
explicit __default_alloc_func(const _Target& __f) : __f_(__f) {}
_LIBCPP_INLINE_VISIBILITY
_Rp operator()(_ArgTypes&&... __arg) {
typedef __invoke_void_return_wrapper<_Rp> _Invoker;
return _Invoker::__call(__f_, _VSTD::forward<_ArgTypes>(__arg)...);
}
_LIBCPP_INLINE_VISIBILITY
__default_alloc_func* __clone() const {
__builtin_new_allocator::__holder_t __hold =
__builtin_new_allocator::__allocate_type<__default_alloc_func>(1);
__default_alloc_func* __res =
::new ((void*)__hold.get()) __default_alloc_func(__f_);
(void)__hold.release();
return __res;
}
_LIBCPP_INLINE_VISIBILITY
void destroy() _NOEXCEPT { __f_.~_Target(); }
static void __destroy_and_delete(__default_alloc_func* __f) {
__f->destroy();
__builtin_new_allocator::__deallocate_type<__default_alloc_func>(__f, 1);
}
};
// __base provides an abstract interface for copyable functors.
template<class _Fp> class _LIBCPP_TEMPLATE_VIS __base;
template<class _Rp, class ..._ArgTypes>
class __base<_Rp(_ArgTypes...)>
{
__base(const __base&);
__base& operator=(const __base&);
public:
_LIBCPP_INLINE_VISIBILITY __base() {}
_LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
virtual __base* __clone() const = 0;
virtual void __clone(__base*) const = 0;
virtual void destroy() _NOEXCEPT = 0;
virtual void destroy_deallocate() _NOEXCEPT = 0;
virtual _Rp operator()(_ArgTypes&& ...) = 0;
#ifndef _LIBCPP_NO_RTTI
virtual const void* target(const type_info&) const _NOEXCEPT = 0;
virtual const std::type_info& target_type() const _NOEXCEPT = 0;
#endif // _LIBCPP_NO_RTTI
};
// __func implements __base for a given functor type.
template<class _FD, class _Alloc, class _FB> class __func;
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
class __func<_Fp, _Alloc, _Rp(_ArgTypes...)>
: public __base<_Rp(_ArgTypes...)>
{
__alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> __f_;
public:
_LIBCPP_INLINE_VISIBILITY
explicit __func(_Fp&& __f)
: __f_(_VSTD::move(__f)) {}
_LIBCPP_INLINE_VISIBILITY
explicit __func(const _Fp& __f, const _Alloc& __a)
: __f_(__f, __a) {}
_LIBCPP_INLINE_VISIBILITY
explicit __func(const _Fp& __f, _Alloc&& __a)
: __f_(__f, _VSTD::move(__a)) {}
_LIBCPP_INLINE_VISIBILITY
explicit __func(_Fp&& __f, _Alloc&& __a)
: __f_(_VSTD::move(__f), _VSTD::move(__a)) {}
virtual __base<_Rp(_ArgTypes...)>* __clone() const;
virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
virtual void destroy() _NOEXCEPT;
virtual void destroy_deallocate() _NOEXCEPT;
virtual _Rp operator()(_ArgTypes&&... __arg);
#ifndef _LIBCPP_NO_RTTI
virtual const void* target(const type_info&) const _NOEXCEPT;
virtual const std::type_info& target_type() const _NOEXCEPT;
#endif // _LIBCPP_NO_RTTI
};
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
__base<_Rp(_ArgTypes...)>*
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone() const
{
typedef allocator_traits<_Alloc> __alloc_traits;
typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
_Ap __a(__f_.__get_allocator());
typedef __allocator_destructor<_Ap> _Dp;
unique_ptr<__func, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
::new ((void*)__hold.get()) __func(__f_.__target(), _Alloc(__a));
return __hold.release();
}
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const
{
::new ((void*)__p) __func(__f_.__target(), __f_.__get_allocator());
}
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy() _NOEXCEPT
{
__f_.destroy();
}
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::destroy_deallocate() _NOEXCEPT
{
typedef allocator_traits<_Alloc> __alloc_traits;
typedef typename __rebind_alloc_helper<__alloc_traits, __func>::type _Ap;
_Ap __a(__f_.__get_allocator());
__f_.destroy();
__a.deallocate(this, 1);
}
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
_Rp
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
{
return __f_(_VSTD::forward<_ArgTypes>(__arg)...);
}
#ifndef _LIBCPP_NO_RTTI
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
const void*
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target(const type_info& __ti) const _NOEXCEPT
{
if (__ti == typeid(_Fp))
return _VSTD::addressof(__f_.__target());
return nullptr;
}
template<class _Fp, class _Alloc, class _Rp, class ..._ArgTypes>
const std::type_info&
__func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
{
return typeid(_Fp);
}
#endif // _LIBCPP_NO_RTTI
// __value_func creates a value-type from a __func.
template <class _Fp> class __value_func;
template <class _Rp, class... _ArgTypes> class __value_func<_Rp(_ArgTypes...)>
{
typename aligned_storage<3 * sizeof(void*)>::type __buf_;
typedef __base<_Rp(_ArgTypes...)> __func;
__func* __f_;
_LIBCPP_NO_CFI static __func* __as_base(void* p)
{
return reinterpret_cast<__func*>(p);
}
public:
_LIBCPP_INLINE_VISIBILITY
__value_func() _NOEXCEPT : __f_(nullptr) {}
template <class _Fp, class _Alloc>
_LIBCPP_INLINE_VISIBILITY __value_func(_Fp&& __f, const _Alloc& __a)
: __f_(nullptr)
{
typedef allocator_traits<_Alloc> __alloc_traits;
typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
typedef typename __rebind_alloc_helper<__alloc_traits, _Fun>::type
_FunAlloc;
if (__function::__not_null(__f))
{
_FunAlloc __af(__a);
if (sizeof(_Fun) <= sizeof(__buf_) &&
is_nothrow_copy_constructible<_Fp>::value &&
is_nothrow_copy_constructible<_FunAlloc>::value)
{
__f_ =
::new ((void*)&__buf_) _Fun(_VSTD::move(__f), _Alloc(__af));
}
else
{
typedef __allocator_destructor<_FunAlloc> _Dp;
unique_ptr<__func, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
::new ((void*)__hold.get()) _Fun(_VSTD::move(__f), _Alloc(__a));
__f_ = __hold.release();
}
}
}
template <class _Fp,
class = typename enable_if<!is_same<typename decay<_Fp>::type, __value_func>::value>::type>
_LIBCPP_INLINE_VISIBILITY explicit __value_func(_Fp&& __f)
: __value_func(_VSTD::forward<_Fp>(__f), allocator<_Fp>()) {}
_LIBCPP_INLINE_VISIBILITY
__value_func(const __value_func& __f)
{
if (__f.__f_ == nullptr)
__f_ = nullptr;
else if ((void*)__f.__f_ == &__f.__buf_)
{
__f_ = __as_base(&__buf_);
__f.__f_->__clone(__f_);
}
else
__f_ = __f.__f_->__clone();
}
_LIBCPP_INLINE_VISIBILITY
__value_func(__value_func&& __f) _NOEXCEPT
{
if (__f.__f_ == nullptr)
__f_ = nullptr;
else if ((void*)__f.__f_ == &__f.__buf_)
{
__f_ = __as_base(&__buf_);
__f.__f_->__clone(__f_);
}
else
{
__f_ = __f.__f_;
__f.__f_ = nullptr;
}
}
_LIBCPP_INLINE_VISIBILITY
~__value_func()
{
if ((void*)__f_ == &__buf_)
__f_->destroy();
else if (__f_)
__f_->destroy_deallocate();
}
_LIBCPP_INLINE_VISIBILITY
__value_func& operator=(__value_func&& __f)
{
*this = nullptr;
if (__f.__f_ == nullptr)
__f_ = nullptr;
else if ((void*)__f.__f_ == &__f.__buf_)
{
__f_ = __as_base(&__buf_);
__f.__f_->__clone(__f_);
}
else
{
__f_ = __f.__f_;
__f.__f_ = nullptr;
}
return *this;
}
_LIBCPP_INLINE_VISIBILITY
__value_func& operator=(nullptr_t)
{
__func* __f = __f_;
__f_ = nullptr;
if ((void*)__f == &__buf_)
__f->destroy();
else if (__f)
__f->destroy_deallocate();
return *this;
}
_LIBCPP_INLINE_VISIBILITY
_Rp operator()(_ArgTypes&&... __args) const
{
if (__f_ == nullptr)
__throw_bad_function_call();
return (*__f_)(_VSTD::forward<_ArgTypes>(__args)...);
}
_LIBCPP_INLINE_VISIBILITY
void swap(__value_func& __f) _NOEXCEPT
{
if (&__f == this)
return;
if ((void*)__f_ == &__buf_ && (void*)__f.__f_ == &__f.__buf_)
{
typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
__func* __t = __as_base(&__tempbuf);
__f_->__clone(__t);
__f_->destroy();
__f_ = nullptr;
__f.__f_->__clone(__as_base(&__buf_));
__f.__f_->destroy();
__f.__f_ = nullptr;
__f_ = __as_base(&__buf_);
__t->__clone(__as_base(&__f.__buf_));
__t->destroy();
__f.__f_ = __as_base(&__f.__buf_);
}
else if ((void*)__f_ == &__buf_)
{
__f_->__clone(__as_base(&__f.__buf_));
__f_->destroy();
__f_ = __f.__f_;
__f.__f_ = __as_base(&__f.__buf_);
}
else if ((void*)__f.__f_ == &__f.__buf_)
{
__f.__f_->__clone(__as_base(&__buf_));
__f.__f_->destroy();
__f.__f_ = __f_;
__f_ = __as_base(&__buf_);
}
else
_VSTD::swap(__f_, __f.__f_);
}
_LIBCPP_INLINE_VISIBILITY
explicit operator bool() const _NOEXCEPT { return __f_ != nullptr; }
#ifndef _LIBCPP_NO_RTTI
_LIBCPP_INLINE_VISIBILITY
const std::type_info& target_type() const _NOEXCEPT
{
if (__f_ == nullptr)
return typeid(void);
return __f_->target_type();
}
template <typename _Tp>
_LIBCPP_INLINE_VISIBILITY const _Tp* target() const _NOEXCEPT
{
if (__f_ == nullptr)
return nullptr;
return (const _Tp*)__f_->target(typeid(_Tp));
}
#endif // _LIBCPP_NO_RTTI
};
// Storage for a functor object, to be used with __policy to manage copy and
// destruction.
union __policy_storage
{
mutable char __small[sizeof(void*) * 2];
void* __large;
};
// True if _Fun can safely be held in __policy_storage.__small.
template <typename _Fun>
struct __use_small_storage
: public integral_constant<
bool, sizeof(_Fun) <= sizeof(__policy_storage) &&
_LIBCPP_ALIGNOF(_Fun) <= _LIBCPP_ALIGNOF(__policy_storage) &&
is_trivially_copy_constructible<_Fun>::value &&
is_trivially_destructible<_Fun>::value> {};
// Policy contains information about how to copy, destroy, and move the
// underlying functor. You can think of it as a vtable of sorts.
struct __policy
{
// Used to copy or destroy __large values. null for trivial objects.
void* (*const __clone)(const void*);
void (*const __destroy)(void*);
// True if this is the null policy (no value).
const bool __is_null;
// The target type. May be null if RTTI is disabled.
const std::type_info* const __type_info;
// Returns a pointer to a static policy object suitable for the functor
// type.
template <typename _Fun>
_LIBCPP_INLINE_VISIBILITY static const __policy* __create()
{
return __choose_policy<_Fun>(__use_small_storage<_Fun>());
}
_LIBCPP_INLINE_VISIBILITY
static const __policy* __create_empty()
{
static const _LIBCPP_CONSTEXPR __policy __policy_ = {nullptr, nullptr,
true,
#ifndef _LIBCPP_NO_RTTI
&typeid(void)
#else
nullptr
#endif
};
return &__policy_;
}
private:
template <typename _Fun> static void* __large_clone(const void* __s)
{
const _Fun* __f = static_cast<const _Fun*>(__s);
return __f->__clone();
}
template <typename _Fun>
static void __large_destroy(void* __s) {
_Fun::__destroy_and_delete(static_cast<_Fun*>(__s));
}
template <typename _Fun>
_LIBCPP_INLINE_VISIBILITY static const __policy*
__choose_policy(/* is_small = */ false_type) {
static const _LIBCPP_CONSTEXPR __policy __policy_ = {
&__large_clone<_Fun>, &__large_destroy<_Fun>, false,
#ifndef _LIBCPP_NO_RTTI
&typeid(typename _Fun::_Target)
#else
nullptr
#endif
};
return &__policy_;
}
template <typename _Fun>
_LIBCPP_INLINE_VISIBILITY static const __policy*
__choose_policy(/* is_small = */ true_type)
{
static const _LIBCPP_CONSTEXPR __policy __policy_ = {
nullptr, nullptr, false,
#ifndef _LIBCPP_NO_RTTI
&typeid(typename _Fun::_Target)
#else
nullptr
#endif
};
return &__policy_;
}
};
// Used to choose between perfect forwarding or pass-by-value. Pass-by-value is
// faster for types that can be passed in registers.
template <typename _Tp>
using __fast_forward =
typename conditional<is_scalar<_Tp>::value, _Tp, _Tp&&>::type;
// __policy_invoker calls an instance of __alloc_func held in __policy_storage.
template <class _Fp> struct __policy_invoker;
template <class _Rp, class... _ArgTypes>
struct __policy_invoker<_Rp(_ArgTypes...)>
{
typedef _Rp (*__Call)(const __policy_storage*,
__fast_forward<_ArgTypes>...);
__Call __call_;
// Creates an invoker that throws bad_function_call.
_LIBCPP_INLINE_VISIBILITY
__policy_invoker() : __call_(&__call_empty) {}
// Creates an invoker that calls the given instance of __func.
template <typename _Fun>
_LIBCPP_INLINE_VISIBILITY static __policy_invoker __create()
{
return __policy_invoker(&__call_impl<_Fun>);
}
private:
_LIBCPP_INLINE_VISIBILITY
explicit __policy_invoker(__Call __c) : __call_(__c) {}
static _Rp __call_empty(const __policy_storage*,
__fast_forward<_ArgTypes>...)
{
__throw_bad_function_call();
}
template <typename _Fun>
static _Rp __call_impl(const __policy_storage* __buf,
__fast_forward<_ArgTypes>... __args)
{
_Fun* __f = reinterpret_cast<_Fun*>(__use_small_storage<_Fun>::value
? &__buf->__small
: __buf->__large);
return (*__f)(_VSTD::forward<_ArgTypes>(__args)...);
}
};
// __policy_func uses a __policy and __policy_invoker to create a type-erased,
// copyable functor.
template <class _Fp> class __policy_func;
template <class _Rp, class... _ArgTypes> class __policy_func<_Rp(_ArgTypes...)>
{
// Inline storage for small objects.
__policy_storage __buf_;
// Calls the value stored in __buf_. This could technically be part of
// policy, but storing it here eliminates a level of indirection inside
// operator().
typedef __function::__policy_invoker<_Rp(_ArgTypes...)> __invoker;
__invoker __invoker_;
// The policy that describes how to move / copy / destroy __buf_. Never
// null, even if the function is empty.
const __policy* __policy_;
public:
_LIBCPP_INLINE_VISIBILITY
__policy_func() : __policy_(__policy::__create_empty()) {}
template <class _Fp, class _Alloc>
_LIBCPP_INLINE_VISIBILITY __policy_func(_Fp&& __f, const _Alloc& __a)
: __policy_(__policy::__create_empty())
{
typedef __alloc_func<_Fp, _Alloc, _Rp(_ArgTypes...)> _Fun;
typedef allocator_traits<_Alloc> __alloc_traits;
typedef typename __rebind_alloc_helper<__alloc_traits, _Fun>::type
_FunAlloc;
if (__function::__not_null(__f))
{
__invoker_ = __invoker::template __create<_Fun>();
__policy_ = __policy::__create<_Fun>();
_FunAlloc __af(__a);
if (__use_small_storage<_Fun>())
{
::new ((void*)&__buf_.__small)
_Fun(_VSTD::move(__f), _Alloc(__af));
}
else
{
typedef __allocator_destructor<_FunAlloc> _Dp;
unique_ptr<_Fun, _Dp> __hold(__af.allocate(1), _Dp(__af, 1));
::new ((void*)__hold.get())
_Fun(_VSTD::move(__f), _Alloc(__af));
__buf_.__large = __hold.release();
}
}
}
template <class _Fp, class = typename enable_if<!is_same<typename decay<_Fp>::type, __policy_func>::value>::type>
_LIBCPP_INLINE_VISIBILITY explicit __policy_func(_Fp&& __f)
: __policy_(__policy::__create_empty()) {
typedef __default_alloc_func<_Fp, _Rp(_ArgTypes...)> _Fun;
if (__function::__not_null(__f)) {
__invoker_ = __invoker::template __create<_Fun>();
__policy_ = __policy::__create<_Fun>();
if (__use_small_storage<_Fun>()) {
::new ((void*)&__buf_.__small) _Fun(_VSTD::move(__f));
} else {
__builtin_new_allocator::__holder_t __hold =
__builtin_new_allocator::__allocate_type<_Fun>(1);
__buf_.__large = ::new ((void*)__hold.get()) _Fun(_VSTD::move(__f));
(void)__hold.release();
}
}
}
_LIBCPP_INLINE_VISIBILITY
__policy_func(const __policy_func& __f)
: __buf_(__f.__buf_), __invoker_(__f.__invoker_),
__policy_(__f.__policy_)
{
if (__policy_->__clone)
__buf_.__large = __policy_->__clone(__f.__buf_.__large);
}
_LIBCPP_INLINE_VISIBILITY
__policy_func(__policy_func&& __f)
: __buf_(__f.__buf_), __invoker_(__f.__invoker_),
__policy_(__f.__policy_)
{
if (__policy_->__destroy)
{
__f.__policy_ = __policy::__create_empty();
__f.__invoker_ = __invoker();
}
}
_LIBCPP_INLINE_VISIBILITY
~__policy_func()
{
if (__policy_->__destroy)
__policy_->__destroy(__buf_.__large);
}
_LIBCPP_INLINE_VISIBILITY
__policy_func& operator=(__policy_func&& __f)
{
*this = nullptr;
__buf_ = __f.__buf_;
__invoker_ = __f.__invoker_;
__policy_ = __f.__policy_;
__f.__policy_ = __policy::__create_empty();
__f.__invoker_ = __invoker();
return *this;
}
_LIBCPP_INLINE_VISIBILITY
__policy_func& operator=(nullptr_t)
{
const __policy* __p = __policy_;
__policy_ = __policy::__create_empty();
__invoker_ = __invoker();
if (__p->__destroy)
__p->__destroy(__buf_.__large);
return *this;
}
_LIBCPP_INLINE_VISIBILITY
_Rp operator()(_ArgTypes&&... __args) const
{
return __invoker_.__call_(_VSTD::addressof(__buf_),
_VSTD::forward<_ArgTypes>(__args)...);
}
_LIBCPP_INLINE_VISIBILITY
void swap(__policy_func& __f)
{
_VSTD::swap(__invoker_, __f.__invoker_);
_VSTD::swap(__policy_, __f.__policy_);
_VSTD::swap(__buf_, __f.__buf_);
}
_LIBCPP_INLINE_VISIBILITY
explicit operator bool() const _NOEXCEPT
{
return !__policy_->__is_null;
}
#ifndef _LIBCPP_NO_RTTI
_LIBCPP_INLINE_VISIBILITY
const std::type_info& target_type() const _NOEXCEPT
{
return *__policy_->__type_info;
}
template <typename _Tp>
_LIBCPP_INLINE_VISIBILITY const _Tp* target() const _NOEXCEPT
{
if (__policy_->__is_null || typeid(_Tp) != *__policy_->__type_info)
return nullptr;
if (__policy_->__clone) // Out of line storage.
return reinterpret_cast<const _Tp*>(__buf_.__large);
else
return reinterpret_cast<const _Tp*>(&__buf_.__small);
}
#endif // _LIBCPP_NO_RTTI
};
#if defined(_LIBCPP_HAS_BLOCKS_RUNTIME) && !defined(_LIBCPP_HAS_OBJC_ARC)
extern "C" void *_Block_copy(const void *);
extern "C" void _Block_release(const void *);
template<class _Rp1, class ..._ArgTypes1, class _Alloc, class _Rp, class ..._ArgTypes>
class __func<_Rp1(^)(_ArgTypes1...), _Alloc, _Rp(_ArgTypes...)>
: public __base<_Rp(_ArgTypes...)>
{
typedef _Rp1(^__block_type)(_ArgTypes1...);
__block_type __f_;
public:
_LIBCPP_INLINE_VISIBILITY
explicit __func(__block_type const& __f)
: __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
{ }
// [TODO] add && to save on a retain
_LIBCPP_INLINE_VISIBILITY
explicit __func(__block_type __f, const _Alloc& /* unused */)
: __f_(reinterpret_cast<__block_type>(__f ? _Block_copy(__f) : nullptr))
{ }
virtual __base<_Rp(_ArgTypes...)>* __clone() const {
_LIBCPP_ASSERT(false,
"Block pointers are just pointers, so they should always fit into "
"std::function's small buffer optimization. This function should "
"never be invoked.");
return nullptr;
}
virtual void __clone(__base<_Rp(_ArgTypes...)>* __p) const {
::new ((void*)__p) __func(__f_);
}
virtual void destroy() _NOEXCEPT {
if (__f_)
_Block_release(__f_);
__f_ = 0;
}
virtual void destroy_deallocate() _NOEXCEPT {
_LIBCPP_ASSERT(false,
"Block pointers are just pointers, so they should always fit into "
"std::function's small buffer optimization. This function should "
"never be invoked.");
}
virtual _Rp operator()(_ArgTypes&& ... __arg) {
return _VSTD::__invoke(__f_, _VSTD::forward<_ArgTypes>(__arg)...);
}
#ifndef _LIBCPP_NO_RTTI
virtual const void* target(type_info const& __ti) const _NOEXCEPT {
if (__ti == typeid(__func::__block_type))
return &__f_;
return (const void*)nullptr;
}
virtual const std::type_info& target_type() const _NOEXCEPT {
return typeid(__func::__block_type);
}
#endif // _LIBCPP_NO_RTTI
};
#endif // _LIBCPP_HAS_EXTENSION_BLOCKS && !_LIBCPP_HAS_OBJC_ARC
} // namespace __function
template<class _Rp, class ..._ArgTypes>
class _LIBCPP_TEMPLATE_VIS function<_Rp(_ArgTypes...)>
#if _LIBCPP_STD_VER <= 17 || !defined(_LIBCPP_ABI_NO_BINDER_BASES)
: public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
#endif
{
#ifndef _LIBCPP_ABI_OPTIMIZED_FUNCTION
typedef __function::__value_func<_Rp(_ArgTypes...)> __func;
#else
typedef __function::__policy_func<_Rp(_ArgTypes...)> __func;
#endif
__func __f_;
template <class _Fp, bool = _And<
_IsNotSame<__uncvref_t<_Fp>, function>,
__invokable<_Fp, _ArgTypes...>
>::value>
struct __callable;
template <class _Fp>
struct __callable<_Fp, true>
{
static const bool value = is_void<_Rp>::value ||
__is_core_convertible<typename __invoke_of<_Fp, _ArgTypes...>::type,
_Rp>::value;
};
template <class _Fp>
struct __callable<_Fp, false>
{
static const bool value = false;
};
template <class _Fp>
using _EnableIfLValueCallable = typename enable_if<__callable<_Fp&>::value>::type;
public:
typedef _Rp result_type;
// construct/copy/destroy:
_LIBCPP_INLINE_VISIBILITY
function() _NOEXCEPT { }
_LIBCPP_INLINE_VISIBILITY
function(nullptr_t) _NOEXCEPT {}
function(const function&);
function(function&&) _NOEXCEPT;
template<class _Fp, class = _EnableIfLValueCallable<_Fp>>
function(_Fp);