-
Notifications
You must be signed in to change notification settings - Fork 57
Expand file tree
/
Copy pathfunction_template.hpp
More file actions
1179 lines (1039 loc) · 35.6 KB
/
Copy pathfunction_template.hpp
File metadata and controls
1179 lines (1039 loc) · 35.6 KB
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
#ifndef BOOST_FUNCTION_FUNCTION_TEMPLATE_HPP_INCLUDED
#define BOOST_FUNCTION_FUNCTION_TEMPLATE_HPP_INCLUDED
// Boost.Function library
// Copyright Douglas Gregor 2001-2006
// Copyright Emil Dotchevski 2007
// Use, modification and distribution is subject to the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// For more information, see http://www.boost.org
#include <boost/function/function_base.hpp>
#include <boost/core/no_exceptions_support.hpp>
#include <boost/mem_fn.hpp>
#include <boost/throw_exception.hpp>
#include <boost/config.hpp>
#include <algorithm>
#include <cassert>
#include <type_traits>
#if defined(BOOST_MSVC)
# pragma warning( push )
# pragma warning( disable : 4127 ) // "conditional expression is constant"
#endif
namespace boost {
namespace detail {
namespace function {
template<
typename FunctionPtr,
typename R,
typename... T
>
struct function_invoker
{
static R invoke(function_buffer& function_ptr,
T... a)
{
FunctionPtr f = reinterpret_cast<FunctionPtr>(function_ptr.members.func_ptr);
return f(static_cast<T&&>(a)...);
}
};
template<
typename FunctionPtr,
typename R,
typename... T
>
struct void_function_invoker
{
static void
invoke(function_buffer& function_ptr,
T... a)
{
FunctionPtr f = reinterpret_cast<FunctionPtr>(function_ptr.members.func_ptr);
f(static_cast<T&&>(a)...);
}
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct function_obj_invoker
{
static R invoke(function_buffer& function_obj_ptr,
T... a)
{
FunctionObj* f;
if (function_allows_small_object_optimization<FunctionObj>::value)
f = reinterpret_cast<FunctionObj*>(function_obj_ptr.data);
else
f = reinterpret_cast<FunctionObj*>(function_obj_ptr.members.obj_ptr);
return (*f)(static_cast<T&&>(a)...);
}
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct void_function_obj_invoker
{
static void
invoke(function_buffer& function_obj_ptr,
T... a)
{
FunctionObj* f;
if (function_allows_small_object_optimization<FunctionObj>::value)
f = reinterpret_cast<FunctionObj*>(function_obj_ptr.data);
else
f = reinterpret_cast<FunctionObj*>(function_obj_ptr.members.obj_ptr);
(*f)(static_cast<T&&>(a)...);
}
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct function_ref_invoker
{
static R invoke(function_buffer& function_obj_ptr,
T... a)
{
FunctionObj* f =
reinterpret_cast<FunctionObj*>(function_obj_ptr.members.obj_ptr);
return (*f)(static_cast<T&&>(a)...);
}
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct void_function_ref_invoker
{
static void
invoke(function_buffer& function_obj_ptr,
T... a)
{
FunctionObj* f =
reinterpret_cast<FunctionObj*>(function_obj_ptr.members.obj_ptr);
(*f)(static_cast<T&&>(a)...);
}
};
/* Handle invocation of member pointers. */
template<
typename MemberPtr,
typename R,
typename... T
>
struct member_invoker
{
static R invoke(function_buffer& function_obj_ptr,
T... a)
{
MemberPtr* f =
reinterpret_cast<MemberPtr*>(function_obj_ptr.data);
return boost::mem_fn(*f)(static_cast<T&&>(a)...);
}
};
template<
typename MemberPtr,
typename R,
typename... T
>
struct void_member_invoker
{
static void
invoke(function_buffer& function_obj_ptr,
T... a)
{
MemberPtr* f =
reinterpret_cast<MemberPtr*>(function_obj_ptr.data);
boost::mem_fn(*f)(static_cast<T&&>(a)...);
}
};
template<
typename FunctionPtr,
typename R,
typename... T
>
struct get_function_invoker
{
typedef typename std::conditional<std::is_void<R>::value,
void_function_invoker<
FunctionPtr,
R,
T...
>,
function_invoker<
FunctionPtr,
R,
T...
>
>::type type;
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct get_function_obj_invoker
{
typedef typename std::conditional<std::is_void<R>::value,
void_function_obj_invoker<
FunctionObj,
R,
T...
>,
function_obj_invoker<
FunctionObj,
R,
T...
>
>::type type;
};
template<
typename FunctionObj,
typename R,
typename... T
>
struct get_function_ref_invoker
{
typedef typename std::conditional<std::is_void<R>::value,
void_function_ref_invoker<
FunctionObj,
R,
T...
>,
function_ref_invoker<
FunctionObj,
R,
T...
>
>::type type;
};
/* Retrieve the appropriate invoker for a member pointer. */
template<
typename MemberPtr,
typename R,
typename... T
>
struct get_member_invoker
{
typedef typename std::conditional<std::is_void<R>::value,
void_member_invoker<
MemberPtr,
R,
T...
>,
member_invoker<
MemberPtr,
R,
T...
>
>::type type;
};
/* Given the tag returned by get_function_tag, retrieve the
actual invoker that will be used for the given function
object.
Each specialization contains an "apply_" nested class template
that accepts the function object, return type, function
argument types, and allocator. The resulting "apply_" class
contains two typedefs, "invoker_type" and "manager_type",
which correspond to the invoker and manager types. */
template<typename Tag>
struct get_invoker { };
/* Retrieve the invoker for a function pointer. */
template<>
struct get_invoker<function_ptr_tag>
{
template<typename FunctionPtr,
typename R, typename... T>
struct apply_
{
typedef typename get_function_invoker<
FunctionPtr,
R,
T...
>::type
invoker_type;
typedef functor_manager<FunctionPtr> manager_type;
};
template<typename FunctionPtr, typename Allocator,
typename R, typename... T>
struct apply_a
{
typedef typename get_function_invoker<
FunctionPtr,
R,
T...
>::type
invoker_type;
typedef functor_manager<FunctionPtr> manager_type;
};
};
/* Retrieve the invoker for a member pointer. */
template<>
struct get_invoker<member_ptr_tag>
{
template<typename MemberPtr,
typename R, typename... T>
struct apply_
{
typedef typename get_member_invoker<
MemberPtr,
R,
T...
>::type
invoker_type;
typedef functor_manager<MemberPtr> manager_type;
};
template<typename MemberPtr, typename Allocator,
typename R, typename... T>
struct apply_a
{
typedef typename get_member_invoker<
MemberPtr,
R,
T...
>::type
invoker_type;
typedef functor_manager<MemberPtr> manager_type;
};
};
/* Retrieve the invoker for a function object. */
template<>
struct get_invoker<function_obj_tag>
{
template<typename FunctionObj,
typename R, typename... T>
struct apply_
{
typedef typename get_function_obj_invoker<
FunctionObj,
R,
T...
>::type
invoker_type;
typedef functor_manager<FunctionObj> manager_type;
};
template<typename FunctionObj, typename Allocator,
typename R, typename... T>
struct apply_a
{
typedef typename get_function_obj_invoker<
FunctionObj,
R,
T...
>::type
invoker_type;
typedef functor_manager_a<FunctionObj, Allocator> manager_type;
};
};
/* Retrieve the invoker for a reference to a function object. */
template<>
struct get_invoker<function_obj_ref_tag>
{
template<typename RefWrapper,
typename R, typename... T>
struct apply_
{
typedef typename get_function_ref_invoker<
typename RefWrapper::type,
R,
T...
>::type
invoker_type;
typedef reference_manager<typename RefWrapper::type> manager_type;
};
template<typename RefWrapper, typename Allocator,
typename R, typename... T>
struct apply_a
{
typedef typename get_function_ref_invoker<
typename RefWrapper::type,
R,
T...
>::type
invoker_type;
typedef reference_manager<typename RefWrapper::type> manager_type;
};
};
/**
* vtable for a specific boost::function instance. This
* structure must be an aggregate so that we can use static
* initialization in boost::function's assign_to and assign_to_a
* members. It therefore cannot have any constructors,
* destructors, base classes, etc.
*/
template<typename R, typename... T>
struct basic_vtable
{
typedef R result_type;
typedef result_type (*invoker_type)(function_buffer&
,
T...);
template<typename F>
bool assign_to(F f, function_buffer& functor) const
{
typedef typename get_function_tag<F>::type tag;
return assign_to(std::move(f), functor, tag());
}
template<typename F,typename Allocator>
bool assign_to_a(F f, function_buffer& functor, Allocator a) const
{
typedef typename get_function_tag<F>::type tag;
return assign_to_a(std::move(f), functor, a, tag());
}
void clear(function_buffer& functor) const
{
#if defined(BOOST_GCC) && (__GNUC__ >= 11)
# pragma GCC diagnostic push
// False positive in GCC 11/12 for empty function objects
# pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif
if (base.manager)
base.manager(functor, functor, destroy_functor_tag);
#if defined(BOOST_GCC) && (__GNUC__ >= 11)
# pragma GCC diagnostic pop
#endif
}
private:
// Function pointers
template<typename FunctionPtr>
bool
assign_to(FunctionPtr f, function_buffer& functor, function_ptr_tag) const
{
this->clear(functor);
if (f) {
functor.members.func_ptr = reinterpret_cast<void (*)()>(f);
return true;
} else {
return false;
}
}
template<typename FunctionPtr,typename Allocator>
bool
assign_to_a(FunctionPtr f, function_buffer& functor, Allocator, function_ptr_tag) const
{
return assign_to(std::move(f),functor,function_ptr_tag());
}
// Member pointers
template<typename MemberPtr>
bool assign_to(MemberPtr f, function_buffer& functor, member_ptr_tag) const
{
// DPG TBD: Add explicit support for member function
// objects, so we invoke through mem_fn() but we retain the
// right target_type() values.
if (f) {
this->assign_to(boost::mem_fn(f), functor);
return true;
} else {
return false;
}
}
template<typename MemberPtr,typename Allocator>
bool assign_to_a(MemberPtr f, function_buffer& functor, Allocator a, member_ptr_tag) const
{
// DPG TBD: Add explicit support for member function
// objects, so we invoke through mem_fn() but we retain the
// right target_type() values.
if (f) {
this->assign_to_a(boost::mem_fn(f), functor, a);
return true;
} else {
return false;
}
}
// Function objects
// Assign to a function object using the small object optimization
template<typename FunctionObj>
void
assign_functor(FunctionObj f, function_buffer& functor, std::true_type) const
{
new (reinterpret_cast<void*>(functor.data)) FunctionObj(std::move(f));
}
template<typename FunctionObj,typename Allocator>
void
assign_functor_a(FunctionObj f, function_buffer& functor, Allocator, std::true_type) const
{
assign_functor(std::move(f),functor,std::true_type());
}
// Assign to a function object allocated on the heap.
template<typename FunctionObj>
void
assign_functor(FunctionObj f, function_buffer& functor, std::false_type) const
{
functor.members.obj_ptr = new FunctionObj(std::move(f));
}
template<typename FunctionObj,typename Allocator>
void
assign_functor_a(FunctionObj f, function_buffer& functor, Allocator a, std::false_type) const
{
typedef functor_wrapper<FunctionObj,Allocator> functor_wrapper_type;
using wrapper_allocator_type = typename std::allocator_traits<Allocator>::template rebind_alloc<functor_wrapper_type>;
using wrapper_allocator_pointer_type = typename std::allocator_traits<wrapper_allocator_type>::pointer;
wrapper_allocator_type wrapper_allocator(a);
wrapper_allocator_pointer_type copy = wrapper_allocator.allocate(1);
std::allocator_traits<wrapper_allocator_type>::construct(wrapper_allocator, copy, functor_wrapper_type(f,a));
functor_wrapper_type* new_f = static_cast<functor_wrapper_type*>(copy);
functor.members.obj_ptr = new_f;
}
template<typename FunctionObj>
bool
assign_to(FunctionObj f, function_buffer& functor, function_obj_tag) const
{
if (!boost::detail::function::has_empty_target(boost::addressof(f))) {
assign_functor(std::move(f), functor,
std::integral_constant<bool, (function_allows_small_object_optimization<FunctionObj>::value)>());
return true;
} else {
return false;
}
}
template<typename FunctionObj,typename Allocator>
bool
assign_to_a(FunctionObj f, function_buffer& functor, Allocator a, function_obj_tag) const
{
if (!boost::detail::function::has_empty_target(boost::addressof(f))) {
assign_functor_a(std::move(f), functor, a,
std::integral_constant<bool, (function_allows_small_object_optimization<FunctionObj>::value)>());
return true;
} else {
return false;
}
}
// Reference to a function object
template<typename FunctionObj>
bool
assign_to(const reference_wrapper<FunctionObj>& f,
function_buffer& functor, function_obj_ref_tag) const
{
functor.members.obj_ref.obj_ptr = (void *)(f.get_pointer());
functor.members.obj_ref.is_const_qualified = std::is_const<FunctionObj>::value;
functor.members.obj_ref.is_volatile_qualified = std::is_volatile<FunctionObj>::value;
return true;
}
template<typename FunctionObj,typename Allocator>
bool
assign_to_a(const reference_wrapper<FunctionObj>& f,
function_buffer& functor, Allocator, function_obj_ref_tag) const
{
return assign_to(f,functor,function_obj_ref_tag());
}
public:
vtable_base base;
invoker_type invoker;
};
template <typename... T>
struct variadic_function_base
{};
template <typename T1>
struct variadic_function_base<T1>
{
typedef T1 argument_type;
typedef T1 arg1_type;
};
template <typename T1, typename T2>
struct variadic_function_base<T1, T2>
{
typedef T1 first_argument_type;
typedef T2 second_argument_type;
typedef T1 arg1_type;
typedef T2 arg2_type;
};
template <typename T1, typename T2, typename T3>
struct variadic_function_base<T1, T2, T3>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
};
template <typename T1, typename T2, typename T3, typename T4>
struct variadic_function_base<T1, T2, T3, T4>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5>
struct variadic_function_base<T1, T2, T3, T4, T5>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6>
struct variadic_function_base<T1, T2, T3, T4, T5, T6>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
typedef T6 arg6_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7>
struct variadic_function_base<T1, T2, T3, T4, T5, T6, T7>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
typedef T6 arg6_type;
typedef T7 arg7_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8>
struct variadic_function_base<T1, T2, T3, T4, T5, T6, T7, T8>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
typedef T6 arg6_type;
typedef T7 arg7_type;
typedef T8 arg8_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8, typename T9>
struct variadic_function_base<T1, T2, T3, T4, T5, T6, T7, T8, T9>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
typedef T6 arg6_type;
typedef T7 arg7_type;
typedef T8 arg8_type;
typedef T9 arg9_type;
};
template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8, typename T9, typename T10>
struct variadic_function_base<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>
{
typedef T1 arg1_type;
typedef T2 arg2_type;
typedef T3 arg3_type;
typedef T4 arg4_type;
typedef T5 arg5_type;
typedef T6 arg6_type;
typedef T7 arg7_type;
typedef T8 arg8_type;
typedef T9 arg9_type;
typedef T10 arg10_type;
};
#if defined( BOOST_LIBSTDCXX_VERSION ) && BOOST_LIBSTDCXX_VERSION < 50000
template<class T> struct is_trivially_copyable: std::integral_constant<bool,
__has_trivial_copy(T) && __has_trivial_assign(T) && __has_trivial_destructor(T)> {};
#else
using std::is_trivially_copyable;
#endif
} // end namespace function
} // end namespace detail
template<
typename R,
typename... T
>
class function_n : public function_base
, public detail::function::variadic_function_base<T...>
{
public:
typedef R result_type;
private:
typedef boost::detail::function::basic_vtable<
R, T...>
vtable_type;
vtable_type* get_vtable() const {
return reinterpret_cast<vtable_type*>(
reinterpret_cast<std::size_t>(vtable) & ~static_cast<std::size_t>(0x01));
}
struct clear_type {};
public:
// add signature for boost::lambda
template<typename Args>
struct sig
{
typedef result_type type;
};
BOOST_STATIC_CONSTANT(int, arity = sizeof...(T));
typedef function_n self_type;
BOOST_DEFAULTED_FUNCTION(function_n(), : function_base() {})
// MSVC chokes if the following two constructors are collapsed into
// one with a default parameter.
template<typename Functor>
function_n(Functor f
,typename std::enable_if<
!std::is_integral<Functor>::value,
int>::type = 0
) :
function_base()
{
this->assign_to(std::move(f));
}
template<typename Functor,typename Allocator>
function_n(Functor f, Allocator a
,typename std::enable_if<
!std::is_integral<Functor>::value,
int>::type = 0
) :
function_base()
{
this->assign_to_a(std::move(f),a);
}
function_n(clear_type*) : function_base() { }
function_n(const function_n& f) : function_base()
{
this->assign_to_own(f);
}
function_n(function_n&& f) : function_base()
{
this->move_assign(f);
}
~function_n() { clear(); }
result_type operator()(T... a) const
{
if (this->empty())
boost::throw_exception(bad_function_call());
return get_vtable()->invoker
(this->functor, static_cast<T&&>(a)...);
}
// The distinction between when to use function_n and
// when to use self_type is obnoxious. MSVC cannot handle self_type as
// the return type of these assignment operators, but Borland C++ cannot
// handle function_n as the type of the temporary to
// construct.
template<typename Functor>
typename std::enable_if<
!std::is_integral<Functor>::value,
function_n&>::type
operator=(Functor f)
{
this->clear();
BOOST_TRY {
this->assign_to(f);
} BOOST_CATCH (...) {
vtable = 0;
BOOST_RETHROW;
}
BOOST_CATCH_END
return *this;
}
template<typename Functor,typename Allocator>
void assign(Functor f, Allocator a)
{
this->clear();
BOOST_TRY{
this->assign_to_a(f,a);
} BOOST_CATCH (...) {
vtable = 0;
BOOST_RETHROW;
}
BOOST_CATCH_END
}
function_n& operator=(clear_type*)
{
this->clear();
return *this;
}
// Assignment from another function_n
function_n& operator=(const function_n& f)
{
if (&f == this)
return *this;
this->clear();
BOOST_TRY {
this->assign_to_own(f);
} BOOST_CATCH (...) {
vtable = 0;
BOOST_RETHROW;
}
BOOST_CATCH_END
return *this;
}
// Move assignment from another function_n
function_n& operator=(function_n&& f)
{
if (&f == this)
return *this;
this->clear();
BOOST_TRY {
this->move_assign(f);
} BOOST_CATCH (...) {
vtable = 0;
BOOST_RETHROW;
}
BOOST_CATCH_END
return *this;
}
void swap(function_n& other)
{
if (&other == this)
return;
function_n tmp;
tmp.move_assign(*this);
this->move_assign(other);
other.move_assign(tmp);
}
// Clear out a target, if there is one
void clear()
{
if (vtable) {
if (!this->has_trivial_copy_and_destroy())
get_vtable()->clear(this->functor);
vtable = 0;
}
}
explicit operator bool () const { return !this->empty(); }
private:
void assign_to_own(const function_n& f)
{
if (!f.empty()) {
this->vtable = f.vtable;
if (this->has_trivial_copy_and_destroy()) {
// Don't operate on storage directly since union type doesn't relax
// strict aliasing rules, despite of having member char type.
# if defined(BOOST_GCC) && (BOOST_GCC >= 40700)
# pragma GCC diagnostic push
// This warning is technically correct, but we don't want to pay the price for initializing
// just to silence a warning: https://github.com/boostorg/function/issues/27
# pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
# if (BOOST_GCC >= 110000)
// GCC 11.3, 12 emit a different warning: https://github.com/boostorg/function/issues/42
# pragma GCC diagnostic ignored "-Wuninitialized"
# endif
# endif
std::memcpy(this->functor.data, f.functor.data, sizeof(boost::detail::function::function_buffer));
# if defined(BOOST_GCC) && (BOOST_GCC >= 40700)
# pragma GCC diagnostic pop
# endif
} else
get_vtable()->base.manager(f.functor, this->functor,
boost::detail::function::clone_functor_tag);
}
}
template<typename Functor>
void assign_to(Functor f)
{
using boost::detail::function::vtable_base;
typedef typename boost::detail::function::get_function_tag<Functor>::type tag;
typedef boost::detail::function::get_invoker<tag> get_invoker;
typedef typename get_invoker::
template apply_<Functor, R,
T...>
handler_type;
typedef typename handler_type::invoker_type invoker_type;
typedef typename handler_type::manager_type manager_type;
// Note: it is extremely important that this initialization use
// static initialization. Otherwise, we will have a race
// condition here in multi-threaded code. See
// http://thread.gmane.org/gmane.comp.lib.boost.devel/164902/.
static const vtable_type stored_vtable =
{ { &manager_type::manage }, &invoker_type::invoke };
if (stored_vtable.assign_to(std::move(f), functor)) {
std::size_t value = reinterpret_cast<std::size_t>(&stored_vtable.base);
// coverity[pointless_expression]: suppress coverity warnings on apparant if(const).
if (boost::detail::function::is_trivially_copyable<Functor>::value &&
boost::detail::function::function_allows_small_object_optimization<Functor>::value)
value |= static_cast<std::size_t>(0x01);
vtable = reinterpret_cast<boost::detail::function::vtable_base *>(value);
} else
vtable = 0;
}
template<typename Functor,typename Allocator>
void assign_to_a(Functor f,Allocator a)
{
using boost::detail::function::vtable_base;
typedef typename boost::detail::function::get_function_tag<Functor>::type tag;
typedef boost::detail::function::get_invoker<tag> get_invoker;
typedef typename get_invoker::
template apply_a<Functor, Allocator, R,
T...>
handler_type;
typedef typename handler_type::invoker_type invoker_type;
typedef typename handler_type::manager_type manager_type;
// Note: it is extremely important that this initialization use
// static initialization. Otherwise, we will have a race
// condition here in multi-threaded code. See
// http://thread.gmane.org/gmane.comp.lib.boost.devel/164902/.
static const vtable_type stored_vtable =
{ { &manager_type::manage }, &invoker_type::invoke };
if (stored_vtable.assign_to_a(std::move(f), functor, a)) {
std::size_t value = reinterpret_cast<std::size_t>(&stored_vtable.base);
// coverity[pointless_expression]: suppress coverity warnings on apparant if(const).
if (boost::detail::function::is_trivially_copyable<Functor>::value &&
boost::detail::function::function_allows_small_object_optimization<Functor>::value)
value |= static_cast<std::size_t>(0x01);
vtable = reinterpret_cast<boost::detail::function::vtable_base *>(value);
} else
vtable = 0;
}
// Moves the value from the specified argument to *this. If the argument
// has its function object allocated on the heap, move_assign will pass
// its buffer to *this, and set the argument's buffer pointer to NULL.
void move_assign(function_n& f)
{
if (&f == this)
return;
BOOST_TRY {
if (!f.empty()) {
this->vtable = f.vtable;
if (this->has_trivial_copy_and_destroy()) {
// Don't operate on storage directly since union type doesn't relax
// strict aliasing rules, despite of having member char type.
# if defined(BOOST_GCC) && (BOOST_GCC >= 40700)
# pragma GCC diagnostic push
// This warning is technically correct, but we don't want to pay the price for initializing