1 // -*- C++ -*- 2 //===------------------------------ any -----------------------------------===// 3 // 4 // The LLVM Compiler Infrastructure 5 // 6 // This file is distributed under the University of Illinois Open Source 7 // License. See LICENSE.TXT for details. 8 // 9 //===----------------------------------------------------------------------===// 10 11 #ifndef _LIBCPP_ANY 12 #define _LIBCPP_ANY 13 14 /* 15 any synopsis 16 17 namespace std { 18 19 class bad_any_cast : public bad_cast 20 { 21 public: 22 virtual const char* what() const noexcept; 23 }; 24 25 class any 26 { 27 public: 28 29 // 6.3.1 any construct/destruct 30 any() noexcept; 31 32 any(const any& other); 33 any(any&& other) noexcept; 34 35 template <class ValueType> 36 any(ValueType&& value); 37 38 ~any(); 39 40 // 6.3.2 any assignments 41 any& operator=(const any& rhs); 42 any& operator=(any&& rhs) noexcept; 43 44 template <class ValueType> 45 any& operator=(ValueType&& rhs); 46 47 // 6.3.3 any modifiers 48 template <class ValueType, class... Args> 49 decay_t<ValueType>& emplace(Args&&... args); 50 template <class ValueType, class U, class... Args> 51 decay_t<ValueType>& emplace(initializer_list<U>, Args&&...); 52 void reset() noexcept; 53 void swap(any& rhs) noexcept; 54 55 // 6.3.4 any observers 56 bool has_value() const noexcept; 57 const type_info& type() const noexcept; 58 }; 59 60 // 6.4 Non-member functions 61 void swap(any& x, any& y) noexcept; 62 63 template <class T, class ...Args> 64 any make_any(Args&& ...args); 65 template <class T, class U, class ...Args> 66 any make_any(initializer_list<U>, Args&& ...args); 67 68 template<class ValueType> 69 ValueType any_cast(const any& operand); 70 template<class ValueType> 71 ValueType any_cast(any& operand); 72 template<class ValueType> 73 ValueType any_cast(any&& operand); 74 75 template<class ValueType> 76 const ValueType* any_cast(const any* operand) noexcept; 77 template<class ValueType> 78 ValueType* any_cast(any* operand) noexcept; 79 80 } // namespace std 81 82 */ 83 84 #include <experimental/__config> 85 #include <memory> 86 #include <new> 87 #include <typeinfo> 88 #include <type_traits> 89 #include <cstdlib> 90 #include <version> 91 92 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 93 #pragma GCC system_header 94 #endif 95 96 namespace std { 97 class _LIBCPP_EXCEPTION_ABI _LIBCPP_AVAILABILITY_BAD_ANY_CAST bad_any_cast : public bad_cast 98 { 99 public: 100 virtual const char* what() const _NOEXCEPT; 101 }; 102 } // namespace std 103 104 _LIBCPP_BEGIN_NAMESPACE_STD 105 106 #if _LIBCPP_STD_VER > 14 107 108 _LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY 109 _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST 110 void __throw_bad_any_cast() 111 { 112 #ifndef _LIBCPP_NO_EXCEPTIONS 113 throw bad_any_cast(); 114 #else 115 _VSTD::abort(); 116 #endif 117 } 118 119 // Forward declarations 120 class _LIBCPP_TEMPLATE_VIS any; 121 122 template <class _ValueType> 123 _LIBCPP_INLINE_VISIBILITY 124 add_pointer_t<add_const_t<_ValueType>> 125 any_cast(any const *) _NOEXCEPT; 126 127 template <class _ValueType> 128 _LIBCPP_INLINE_VISIBILITY 129 add_pointer_t<_ValueType> any_cast(any *) _NOEXCEPT; 130 131 namespace __any_imp 132 { 133 using _Buffer = aligned_storage_t<3*sizeof(void*), alignment_of<void*>::value>; 134 135 template <class _Tp> 136 using _IsSmallObject = integral_constant<bool 137 , sizeof(_Tp) <= sizeof(_Buffer) 138 && alignment_of<_Buffer>::value 139 % alignment_of<_Tp>::value == 0 140 && is_nothrow_move_constructible<_Tp>::value 141 >; 142 143 enum class _Action { 144 _Destroy, 145 _Copy, 146 _Move, 147 _Get, 148 _TypeInfo 149 }; 150 151 template <class _Tp> struct _SmallHandler; 152 template <class _Tp> struct _LargeHandler; 153 154 template <class _Tp> 155 struct _LIBCPP_TEMPLATE_VIS __unique_typeinfo { static constexpr int __id = 0; }; 156 template <class _Tp> constexpr int __unique_typeinfo<_Tp>::__id; 157 158 template <class _Tp> 159 inline _LIBCPP_INLINE_VISIBILITY 160 constexpr const void* __get_fallback_typeid() { 161 return &__unique_typeinfo<decay_t<_Tp>>::__id; 162 } 163 164 template <class _Tp> 165 inline _LIBCPP_INLINE_VISIBILITY 166 bool __compare_typeid(type_info const* __id, const void* __fallback_id) 167 { 168 #if !defined(_LIBCPP_NO_RTTI) 169 if (__id && *__id == typeid(_Tp)) 170 return true; 171 #endif 172 if (!__id && __fallback_id == __any_imp::__get_fallback_typeid<_Tp>()) 173 return true; 174 return false; 175 } 176 177 template <class _Tp> 178 using _Handler = conditional_t< 179 _IsSmallObject<_Tp>::value, _SmallHandler<_Tp>, _LargeHandler<_Tp>>; 180 181 } // namespace __any_imp 182 183 class _LIBCPP_TEMPLATE_VIS any 184 { 185 public: 186 // construct/destruct 187 _LIBCPP_INLINE_VISIBILITY 188 constexpr any() _NOEXCEPT : __h(nullptr) {} 189 190 _LIBCPP_INLINE_VISIBILITY 191 any(any const & __other) : __h(nullptr) 192 { 193 if (__other.__h) __other.__call(_Action::_Copy, this); 194 } 195 196 _LIBCPP_INLINE_VISIBILITY 197 any(any && __other) _NOEXCEPT : __h(nullptr) 198 { 199 if (__other.__h) __other.__call(_Action::_Move, this); 200 } 201 202 template < 203 class _ValueType 204 , class _Tp = decay_t<_ValueType> 205 , class = enable_if_t< 206 !is_same<_Tp, any>::value && 207 !__is_inplace_type<_ValueType>::value && 208 is_copy_constructible<_Tp>::value> 209 > 210 _LIBCPP_INLINE_VISIBILITY 211 any(_ValueType && __value); 212 213 template <class _ValueType, class ..._Args, 214 class _Tp = decay_t<_ValueType>, 215 class = enable_if_t< 216 is_constructible<_Tp, _Args...>::value && 217 is_copy_constructible<_Tp>::value 218 > 219 > 220 _LIBCPP_INLINE_VISIBILITY 221 explicit any(in_place_type_t<_ValueType>, _Args&&... __args); 222 223 template <class _ValueType, class _Up, class ..._Args, 224 class _Tp = decay_t<_ValueType>, 225 class = enable_if_t< 226 is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value && 227 is_copy_constructible<_Tp>::value> 228 > 229 _LIBCPP_INLINE_VISIBILITY 230 explicit any(in_place_type_t<_ValueType>, initializer_list<_Up>, _Args&&... __args); 231 232 _LIBCPP_INLINE_VISIBILITY 233 ~any() { this->reset(); } 234 235 // assignments 236 _LIBCPP_INLINE_VISIBILITY 237 any & operator=(any const & __rhs) { 238 any(__rhs).swap(*this); 239 return *this; 240 } 241 242 _LIBCPP_INLINE_VISIBILITY 243 any & operator=(any && __rhs) _NOEXCEPT { 244 any(_VSTD::move(__rhs)).swap(*this); 245 return *this; 246 } 247 248 template < 249 class _ValueType 250 , class _Tp = decay_t<_ValueType> 251 , class = enable_if_t< 252 !is_same<_Tp, any>::value 253 && is_copy_constructible<_Tp>::value> 254 > 255 _LIBCPP_INLINE_VISIBILITY 256 any & operator=(_ValueType && __rhs); 257 258 template <class _ValueType, class ..._Args, 259 class _Tp = decay_t<_ValueType>, 260 class = enable_if_t< 261 is_constructible<_Tp, _Args...>::value && 262 is_copy_constructible<_Tp>::value> 263 > 264 _LIBCPP_INLINE_VISIBILITY 265 _Tp& emplace(_Args&&... args); 266 267 template <class _ValueType, class _Up, class ..._Args, 268 class _Tp = decay_t<_ValueType>, 269 class = enable_if_t< 270 is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value && 271 is_copy_constructible<_Tp>::value> 272 > 273 _LIBCPP_INLINE_VISIBILITY 274 _Tp& emplace(initializer_list<_Up>, _Args&&...); 275 276 // 6.3.3 any modifiers 277 _LIBCPP_INLINE_VISIBILITY 278 void reset() _NOEXCEPT { if (__h) this->__call(_Action::_Destroy); } 279 280 _LIBCPP_INLINE_VISIBILITY 281 void swap(any & __rhs) _NOEXCEPT; 282 283 // 6.3.4 any observers 284 _LIBCPP_INLINE_VISIBILITY 285 bool has_value() const _NOEXCEPT { return __h != nullptr; } 286 287 #if !defined(_LIBCPP_NO_RTTI) 288 _LIBCPP_INLINE_VISIBILITY 289 const type_info & type() const _NOEXCEPT { 290 if (__h) { 291 return *static_cast<type_info const *>(this->__call(_Action::_TypeInfo)); 292 } else { 293 return typeid(void); 294 } 295 } 296 #endif 297 298 private: 299 typedef __any_imp::_Action _Action; 300 using _HandleFuncPtr = void* (*)(_Action, any const *, any *, const type_info *, 301 const void* __fallback_info); 302 303 union _Storage { 304 constexpr _Storage() : __ptr(nullptr) {} 305 void * __ptr; 306 __any_imp::_Buffer __buf; 307 }; 308 309 _LIBCPP_INLINE_VISIBILITY 310 void * __call(_Action __a, any * __other = nullptr, 311 type_info const * __info = nullptr, 312 const void* __fallback_info = nullptr) const 313 { 314 return __h(__a, this, __other, __info, __fallback_info); 315 } 316 317 _LIBCPP_INLINE_VISIBILITY 318 void * __call(_Action __a, any * __other = nullptr, 319 type_info const * __info = nullptr, 320 const void* __fallback_info = nullptr) 321 { 322 return __h(__a, this, __other, __info, __fallback_info); 323 } 324 325 template <class> 326 friend struct __any_imp::_SmallHandler; 327 template <class> 328 friend struct __any_imp::_LargeHandler; 329 330 template <class _ValueType> 331 friend add_pointer_t<add_const_t<_ValueType>> 332 any_cast(any const *) _NOEXCEPT; 333 334 template <class _ValueType> 335 friend add_pointer_t<_ValueType> 336 any_cast(any *) _NOEXCEPT; 337 338 _HandleFuncPtr __h = nullptr; 339 _Storage __s; 340 }; 341 342 namespace __any_imp 343 { 344 template <class _Tp> 345 struct _LIBCPP_TEMPLATE_VIS _SmallHandler 346 { 347 _LIBCPP_INLINE_VISIBILITY 348 static void* __handle(_Action __act, any const * __this, any * __other, 349 type_info const * __info, const void* __fallback_info) 350 { 351 switch (__act) 352 { 353 case _Action::_Destroy: 354 __destroy(const_cast<any &>(*__this)); 355 return nullptr; 356 case _Action::_Copy: 357 __copy(*__this, *__other); 358 return nullptr; 359 case _Action::_Move: 360 __move(const_cast<any &>(*__this), *__other); 361 return nullptr; 362 case _Action::_Get: 363 return __get(const_cast<any &>(*__this), __info, __fallback_info); 364 case _Action::_TypeInfo: 365 return __type_info(); 366 } 367 } 368 369 template <class ..._Args> 370 _LIBCPP_INLINE_VISIBILITY 371 static _Tp& __create(any & __dest, _Args&&... __args) { 372 _Tp* __ret = ::new (static_cast<void*>(&__dest.__s.__buf)) _Tp(_VSTD::forward<_Args>(__args)...); 373 __dest.__h = &_SmallHandler::__handle; 374 return *__ret; 375 } 376 377 private: 378 _LIBCPP_INLINE_VISIBILITY 379 static void __destroy(any & __this) { 380 _Tp & __value = *static_cast<_Tp *>(static_cast<void*>(&__this.__s.__buf)); 381 __value.~_Tp(); 382 __this.__h = nullptr; 383 } 384 385 _LIBCPP_INLINE_VISIBILITY 386 static void __copy(any const & __this, any & __dest) { 387 _SmallHandler::__create(__dest, *static_cast<_Tp const *>( 388 static_cast<void const *>(&__this.__s.__buf))); 389 } 390 391 _LIBCPP_INLINE_VISIBILITY 392 static void __move(any & __this, any & __dest) { 393 _SmallHandler::__create(__dest, _VSTD::move( 394 *static_cast<_Tp*>(static_cast<void*>(&__this.__s.__buf)))); 395 __destroy(__this); 396 } 397 398 _LIBCPP_INLINE_VISIBILITY 399 static void* __get(any & __this, 400 type_info const * __info, 401 const void* __fallback_id) 402 { 403 if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_id)) 404 return static_cast<void*>(&__this.__s.__buf); 405 return nullptr; 406 } 407 408 _LIBCPP_INLINE_VISIBILITY 409 static void* __type_info() 410 { 411 #if !defined(_LIBCPP_NO_RTTI) 412 return const_cast<void*>(static_cast<void const *>(&typeid(_Tp))); 413 #else 414 return nullptr; 415 #endif 416 } 417 }; 418 419 template <class _Tp> 420 struct _LIBCPP_TEMPLATE_VIS _LargeHandler 421 { 422 _LIBCPP_INLINE_VISIBILITY 423 static void* __handle(_Action __act, any const * __this, 424 any * __other, type_info const * __info, 425 void const* __fallback_info) 426 { 427 switch (__act) 428 { 429 case _Action::_Destroy: 430 __destroy(const_cast<any &>(*__this)); 431 return nullptr; 432 case _Action::_Copy: 433 __copy(*__this, *__other); 434 return nullptr; 435 case _Action::_Move: 436 __move(const_cast<any &>(*__this), *__other); 437 return nullptr; 438 case _Action::_Get: 439 return __get(const_cast<any &>(*__this), __info, __fallback_info); 440 case _Action::_TypeInfo: 441 return __type_info(); 442 } 443 } 444 445 template <class ..._Args> 446 _LIBCPP_INLINE_VISIBILITY 447 static _Tp& __create(any & __dest, _Args&&... __args) { 448 typedef allocator<_Tp> _Alloc; 449 typedef __allocator_destructor<_Alloc> _Dp; 450 _Alloc __a; 451 unique_ptr<_Tp, _Dp> __hold(__a.allocate(1), _Dp(__a, 1)); 452 _Tp* __ret = ::new ((void*)__hold.get()) _Tp(_VSTD::forward<_Args>(__args)...); 453 __dest.__s.__ptr = __hold.release(); 454 __dest.__h = &_LargeHandler::__handle; 455 return *__ret; 456 } 457 458 private: 459 460 _LIBCPP_INLINE_VISIBILITY 461 static void __destroy(any & __this){ 462 delete static_cast<_Tp*>(__this.__s.__ptr); 463 __this.__h = nullptr; 464 } 465 466 _LIBCPP_INLINE_VISIBILITY 467 static void __copy(any const & __this, any & __dest) { 468 _LargeHandler::__create(__dest, *static_cast<_Tp const *>(__this.__s.__ptr)); 469 } 470 471 _LIBCPP_INLINE_VISIBILITY 472 static void __move(any & __this, any & __dest) { 473 __dest.__s.__ptr = __this.__s.__ptr; 474 __dest.__h = &_LargeHandler::__handle; 475 __this.__h = nullptr; 476 } 477 478 _LIBCPP_INLINE_VISIBILITY 479 static void* __get(any & __this, type_info const * __info, 480 void const* __fallback_info) 481 { 482 if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_info)) 483 return static_cast<void*>(__this.__s.__ptr); 484 return nullptr; 485 486 } 487 488 _LIBCPP_INLINE_VISIBILITY 489 static void* __type_info() 490 { 491 #if !defined(_LIBCPP_NO_RTTI) 492 return const_cast<void*>(static_cast<void const *>(&typeid(_Tp))); 493 #else 494 return nullptr; 495 #endif 496 } 497 }; 498 499 } // namespace __any_imp 500 501 502 template <class _ValueType, class _Tp, class> 503 any::any(_ValueType && __v) : __h(nullptr) 504 { 505 __any_imp::_Handler<_Tp>::__create(*this, _VSTD::forward<_ValueType>(__v)); 506 } 507 508 template <class _ValueType, class ..._Args, class _Tp, class> 509 any::any(in_place_type_t<_ValueType>, _Args&&... __args) { 510 __any_imp::_Handler<_Tp>::__create(*this, _VSTD::forward<_Args>(__args)...); 511 }; 512 513 template <class _ValueType, class _Up, class ..._Args, class _Tp, class> 514 any::any(in_place_type_t<_ValueType>, initializer_list<_Up> __il, _Args&&... __args) { 515 __any_imp::_Handler<_Tp>::__create(*this, __il, _VSTD::forward<_Args>(__args)...); 516 } 517 518 template <class _ValueType, class, class> 519 inline _LIBCPP_INLINE_VISIBILITY 520 any & any::operator=(_ValueType && __v) 521 { 522 any(_VSTD::forward<_ValueType>(__v)).swap(*this); 523 return *this; 524 } 525 526 template <class _ValueType, class ..._Args, class _Tp, class> 527 inline _LIBCPP_INLINE_VISIBILITY 528 _Tp& any::emplace(_Args&&... __args) { 529 reset(); 530 return __any_imp::_Handler<_Tp>::__create(*this, _VSTD::forward<_Args>(__args)...); 531 } 532 533 template <class _ValueType, class _Up, class ..._Args, class _Tp, class> 534 inline _LIBCPP_INLINE_VISIBILITY 535 _Tp& any::emplace(initializer_list<_Up> __il, _Args&&... __args) { 536 reset(); 537 return __any_imp::_Handler<_Tp>::__create(*this, __il, _VSTD::forward<_Args>(__args)...); 538 } 539 540 inline _LIBCPP_INLINE_VISIBILITY 541 void any::swap(any & __rhs) _NOEXCEPT 542 { 543 if (this == &__rhs) 544 return; 545 if (__h && __rhs.__h) { 546 any __tmp; 547 __rhs.__call(_Action::_Move, &__tmp); 548 this->__call(_Action::_Move, &__rhs); 549 __tmp.__call(_Action::_Move, this); 550 } 551 else if (__h) { 552 this->__call(_Action::_Move, &__rhs); 553 } 554 else if (__rhs.__h) { 555 __rhs.__call(_Action::_Move, this); 556 } 557 } 558 559 // 6.4 Non-member functions 560 561 inline _LIBCPP_INLINE_VISIBILITY 562 void swap(any & __lhs, any & __rhs) _NOEXCEPT 563 { 564 __lhs.swap(__rhs); 565 } 566 567 template <class _Tp, class ..._Args> 568 inline _LIBCPP_INLINE_VISIBILITY 569 any make_any(_Args&&... __args) { 570 return any(in_place_type<_Tp>, _VSTD::forward<_Args>(__args)...); 571 } 572 573 template <class _Tp, class _Up, class ..._Args> 574 inline _LIBCPP_INLINE_VISIBILITY 575 any make_any(initializer_list<_Up> __il, _Args&&... __args) { 576 return any(in_place_type<_Tp>, __il, _VSTD::forward<_Args>(__args)...); 577 } 578 579 template <class _ValueType> 580 inline _LIBCPP_INLINE_VISIBILITY 581 _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST 582 _ValueType any_cast(any const & __v) 583 { 584 using _RawValueType = __uncvref_t<_ValueType>; 585 static_assert(is_constructible<_ValueType, _RawValueType const &>::value, 586 "ValueType is required to be a const lvalue reference " 587 "or a CopyConstructible type"); 588 auto __tmp = _VSTD::any_cast<add_const_t<_RawValueType>>(&__v); 589 if (__tmp == nullptr) 590 __throw_bad_any_cast(); 591 return static_cast<_ValueType>(*__tmp); 592 } 593 594 template <class _ValueType> 595 inline _LIBCPP_INLINE_VISIBILITY 596 _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST 597 _ValueType any_cast(any & __v) 598 { 599 using _RawValueType = __uncvref_t<_ValueType>; 600 static_assert(is_constructible<_ValueType, _RawValueType &>::value, 601 "ValueType is required to be an lvalue reference " 602 "or a CopyConstructible type"); 603 auto __tmp = _VSTD::any_cast<_RawValueType>(&__v); 604 if (__tmp == nullptr) 605 __throw_bad_any_cast(); 606 return static_cast<_ValueType>(*__tmp); 607 } 608 609 template <class _ValueType> 610 inline _LIBCPP_INLINE_VISIBILITY 611 _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST 612 _ValueType any_cast(any && __v) 613 { 614 using _RawValueType = __uncvref_t<_ValueType>; 615 static_assert(is_constructible<_ValueType, _RawValueType>::value, 616 "ValueType is required to be an rvalue reference " 617 "or a CopyConstructible type"); 618 auto __tmp = _VSTD::any_cast<_RawValueType>(&__v); 619 if (__tmp == nullptr) 620 __throw_bad_any_cast(); 621 return static_cast<_ValueType>(_VSTD::move(*__tmp)); 622 } 623 624 template <class _ValueType> 625 inline _LIBCPP_INLINE_VISIBILITY 626 add_pointer_t<add_const_t<_ValueType>> 627 any_cast(any const * __any) _NOEXCEPT 628 { 629 static_assert(!is_reference<_ValueType>::value, 630 "_ValueType may not be a reference."); 631 return _VSTD::any_cast<_ValueType>(const_cast<any *>(__any)); 632 } 633 634 template <class _RetType> 635 inline _LIBCPP_INLINE_VISIBILITY 636 _RetType __pointer_or_func_cast(void* __p, /*IsFunction*/false_type) noexcept { 637 return static_cast<_RetType>(__p); 638 } 639 640 template <class _RetType> 641 inline _LIBCPP_INLINE_VISIBILITY 642 _RetType __pointer_or_func_cast(void*, /*IsFunction*/true_type) noexcept { 643 return nullptr; 644 } 645 646 template <class _ValueType> 647 add_pointer_t<_ValueType> 648 any_cast(any * __any) _NOEXCEPT 649 { 650 using __any_imp::_Action; 651 static_assert(!is_reference<_ValueType>::value, 652 "_ValueType may not be a reference."); 653 typedef typename add_pointer<_ValueType>::type _ReturnType; 654 if (__any && __any->__h) { 655 void *__p = __any->__call(_Action::_Get, nullptr, 656 #if !defined(_LIBCPP_NO_RTTI) 657 &typeid(_ValueType), 658 #else 659 nullptr, 660 #endif 661 __any_imp::__get_fallback_typeid<_ValueType>()); 662 return _VSTD::__pointer_or_func_cast<_ReturnType>( 663 __p, is_function<_ValueType>{}); 664 } 665 return nullptr; 666 } 667 668 #endif // _LIBCPP_STD_VER > 14 669 670 _LIBCPP_END_NAMESPACE_STD 671 672 #endif // _LIBCPP_ANY 673
