1// -*- C++ -*- 2//===-------------------------- exception ---------------------------------===// 3// 4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5// See https://llvm.org/LICENSE.txt for license information. 6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7// 8//===----------------------------------------------------------------------===// 9 10#ifndef _LIBCPP_EXCEPTION 11#define _LIBCPP_EXCEPTION 12 13/* 14 exception synopsis 15 16namespace std 17{ 18 19class exception 20{ 21public: 22 exception() noexcept; 23 exception(const exception&) noexcept; 24 exception& operator=(const exception&) noexcept; 25 virtual ~exception() noexcept; 26 virtual const char* what() const noexcept; 27}; 28 29class bad_exception 30 : public exception 31{ 32public: 33 bad_exception() noexcept; 34 bad_exception(const bad_exception&) noexcept; 35 bad_exception& operator=(const bad_exception&) noexcept; 36 virtual ~bad_exception() noexcept; 37 virtual const char* what() const noexcept; 38}; 39 40typedef void (*unexpected_handler)(); 41unexpected_handler set_unexpected(unexpected_handler f ) noexcept; 42unexpected_handler get_unexpected() noexcept; 43[[noreturn]] void unexpected(); 44 45typedef void (*terminate_handler)(); 46terminate_handler set_terminate(terminate_handler f ) noexcept; 47terminate_handler get_terminate() noexcept; 48[[noreturn]] void terminate() noexcept; 49 50bool uncaught_exception() noexcept; 51int uncaught_exceptions() noexcept; // C++17 52 53typedef unspecified exception_ptr; 54 55exception_ptr current_exception() noexcept; 56void rethrow_exception [[noreturn]] (exception_ptr p); 57template<class E> exception_ptr make_exception_ptr(E e) noexcept; 58 59class nested_exception 60{ 61public: 62 nested_exception() noexcept; 63 nested_exception(const nested_exception&) noexcept = default; 64 nested_exception& operator=(const nested_exception&) noexcept = default; 65 virtual ~nested_exception() = default; 66 67 // access functions 68 [[noreturn]] void rethrow_nested() const; 69 exception_ptr nested_ptr() const noexcept; 70}; 71 72template <class T> [[noreturn]] void throw_with_nested(T&& t); 73template <class E> void rethrow_if_nested(const E& e); 74 75} // std 76 77*/ 78 79#include <__config> 80#include <__availability> 81#include <__memory/base.h> 82#include <cstddef> 83#include <cstdlib> 84#include <type_traits> 85#include <version> 86 87#if defined(_LIBCPP_ABI_VCRUNTIME) 88#include <vcruntime_exception.h> 89#endif 90 91#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 92#pragma GCC system_header 93#endif 94 95namespace std // purposefully not using versioning namespace 96{ 97 98#if !defined(_LIBCPP_ABI_VCRUNTIME) 99class _LIBCPP_EXCEPTION_ABI exception 100{ 101public: 102 _LIBCPP_INLINE_VISIBILITY exception() _NOEXCEPT {} 103 _LIBCPP_INLINE_VISIBILITY exception(const exception&) _NOEXCEPT = default; 104 105 virtual ~exception() _NOEXCEPT; 106 virtual const char* what() const _NOEXCEPT; 107}; 108 109class _LIBCPP_EXCEPTION_ABI bad_exception 110 : public exception 111{ 112public: 113 _LIBCPP_INLINE_VISIBILITY bad_exception() _NOEXCEPT {} 114 virtual ~bad_exception() _NOEXCEPT; 115 virtual const char* what() const _NOEXCEPT; 116}; 117#endif // !_LIBCPP_ABI_VCRUNTIME 118 119#if _LIBCPP_STD_VER <= 14 \ 120 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS) \ 121 || defined(_LIBCPP_BUILDING_LIBRARY) 122typedef void (*unexpected_handler)(); 123_LIBCPP_FUNC_VIS unexpected_handler set_unexpected(unexpected_handler) _NOEXCEPT; 124_LIBCPP_FUNC_VIS unexpected_handler get_unexpected() _NOEXCEPT; 125_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void unexpected(); 126#endif 127 128typedef void (*terminate_handler)(); 129_LIBCPP_FUNC_VIS terminate_handler set_terminate(terminate_handler) _NOEXCEPT; 130_LIBCPP_FUNC_VIS terminate_handler get_terminate() _NOEXCEPT; 131_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void terminate() _NOEXCEPT; 132 133_LIBCPP_FUNC_VIS bool uncaught_exception() _NOEXCEPT; 134_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS int uncaught_exceptions() _NOEXCEPT; 135 136class _LIBCPP_TYPE_VIS exception_ptr; 137 138_LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT; 139_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr); 140 141#ifndef _LIBCPP_ABI_MICROSOFT 142 143class _LIBCPP_TYPE_VIS exception_ptr 144{ 145 void* __ptr_; 146public: 147 _LIBCPP_INLINE_VISIBILITY exception_ptr() _NOEXCEPT : __ptr_() {} 148 _LIBCPP_INLINE_VISIBILITY exception_ptr(nullptr_t) _NOEXCEPT : __ptr_() {} 149 150 exception_ptr(const exception_ptr&) _NOEXCEPT; 151 exception_ptr& operator=(const exception_ptr&) _NOEXCEPT; 152 ~exception_ptr() _NOEXCEPT; 153 154 _LIBCPP_INLINE_VISIBILITY _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT 155 {return __ptr_ != nullptr;} 156 157 friend _LIBCPP_INLINE_VISIBILITY 158 bool operator==(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT 159 {return __x.__ptr_ == __y.__ptr_;} 160 161 friend _LIBCPP_INLINE_VISIBILITY 162 bool operator!=(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT 163 {return !(__x == __y);} 164 165 friend _LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT; 166 friend _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr); 167}; 168 169template<class _Ep> 170_LIBCPP_INLINE_VISIBILITY exception_ptr 171make_exception_ptr(_Ep __e) _NOEXCEPT 172{ 173#ifndef _LIBCPP_NO_EXCEPTIONS 174 try 175 { 176 throw __e; 177 } 178 catch (...) 179 { 180 return current_exception(); 181 } 182#else 183 ((void)__e); 184 _VSTD::abort(); 185#endif 186} 187 188#else // _LIBCPP_ABI_MICROSOFT 189 190class _LIBCPP_TYPE_VIS exception_ptr 191{ 192#if defined(__clang__) 193#pragma clang diagnostic push 194#pragma clang diagnostic ignored "-Wunused-private-field" 195#endif 196 void* __ptr1_; 197 void* __ptr2_; 198#if defined(__clang__) 199#pragma clang diagnostic pop 200#endif 201public: 202 exception_ptr() _NOEXCEPT; 203 exception_ptr(nullptr_t) _NOEXCEPT; 204 exception_ptr(const exception_ptr& __other) _NOEXCEPT; 205 exception_ptr& operator=(const exception_ptr& __other) _NOEXCEPT; 206 exception_ptr& operator=(nullptr_t) _NOEXCEPT; 207 ~exception_ptr() _NOEXCEPT; 208 _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT; 209}; 210 211_LIBCPP_FUNC_VIS 212bool operator==(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT; 213 214inline _LIBCPP_INLINE_VISIBILITY 215bool operator!=(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT 216 {return !(__x == __y);} 217 218_LIBCPP_FUNC_VIS void swap(exception_ptr&, exception_ptr&) _NOEXCEPT; 219 220_LIBCPP_FUNC_VIS exception_ptr __copy_exception_ptr(void *__except, const void* __ptr); 221_LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT; 222_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr p); 223 224// This is a built-in template function which automagically extracts the required 225// information. 226template <class _E> void *__GetExceptionInfo(_E); 227 228template<class _Ep> 229_LIBCPP_INLINE_VISIBILITY exception_ptr 230make_exception_ptr(_Ep __e) _NOEXCEPT 231{ 232 return __copy_exception_ptr(_VSTD::addressof(__e), __GetExceptionInfo(__e)); 233} 234 235#endif // _LIBCPP_ABI_MICROSOFT 236// nested_exception 237 238class _LIBCPP_EXCEPTION_ABI nested_exception 239{ 240 exception_ptr __ptr_; 241public: 242 nested_exception() _NOEXCEPT; 243// nested_exception(const nested_exception&) noexcept = default; 244// nested_exception& operator=(const nested_exception&) noexcept = default; 245 virtual ~nested_exception() _NOEXCEPT; 246 247 // access functions 248 _LIBCPP_NORETURN void rethrow_nested() const; 249 _LIBCPP_INLINE_VISIBILITY exception_ptr nested_ptr() const _NOEXCEPT {return __ptr_;} 250}; 251 252template <class _Tp> 253struct __nested 254 : public _Tp, 255 public nested_exception 256{ 257 _LIBCPP_INLINE_VISIBILITY explicit __nested(const _Tp& __t) : _Tp(__t) {} 258}; 259 260#ifndef _LIBCPP_NO_EXCEPTIONS 261template <class _Tp, class _Up, bool> 262struct __throw_with_nested; 263 264template <class _Tp, class _Up> 265struct __throw_with_nested<_Tp, _Up, true> { 266 _LIBCPP_NORETURN static inline _LIBCPP_INLINE_VISIBILITY void 267 __do_throw(_Tp&& __t) 268 { 269 throw __nested<_Up>(_VSTD::forward<_Tp>(__t)); 270 } 271}; 272 273template <class _Tp, class _Up> 274struct __throw_with_nested<_Tp, _Up, false> { 275 _LIBCPP_NORETURN static inline _LIBCPP_INLINE_VISIBILITY void 276#ifndef _LIBCPP_CXX03_LANG 277 __do_throw(_Tp&& __t) 278#else 279 __do_throw (_Tp& __t) 280#endif // _LIBCPP_CXX03_LANG 281 { 282 throw _VSTD::forward<_Tp>(__t); 283 } 284}; 285#endif 286 287template <class _Tp> 288_LIBCPP_NORETURN 289void 290throw_with_nested(_Tp&& __t) 291{ 292#ifndef _LIBCPP_NO_EXCEPTIONS 293 typedef typename decay<_Tp>::type _Up; 294 static_assert( is_copy_constructible<_Up>::value, "type thrown must be CopyConstructible"); 295 __throw_with_nested<_Tp, _Up, 296 is_class<_Up>::value && 297 !is_base_of<nested_exception, _Up>::value && 298 !__libcpp_is_final<_Up>::value>:: 299 __do_throw(_VSTD::forward<_Tp>(__t)); 300#else 301 ((void)__t); 302 // FIXME: Make this abort 303#endif 304} 305 306template <class _From, class _To> 307struct __can_dynamic_cast : public _LIBCPP_BOOL_CONSTANT( 308 is_polymorphic<_From>::value && 309 (!is_base_of<_To, _From>::value || 310 is_convertible<const _From*, const _To*>::value)) {}; 311 312template <class _Ep> 313inline _LIBCPP_INLINE_VISIBILITY 314void 315rethrow_if_nested(const _Ep& __e, 316 typename enable_if< __can_dynamic_cast<_Ep, nested_exception>::value>::type* = 0) 317{ 318 const nested_exception* __nep = dynamic_cast<const nested_exception*>(_VSTD::addressof(__e)); 319 if (__nep) 320 __nep->rethrow_nested(); 321} 322 323template <class _Ep> 324inline _LIBCPP_INLINE_VISIBILITY 325void 326rethrow_if_nested(const _Ep&, 327 typename enable_if<!__can_dynamic_cast<_Ep, nested_exception>::value>::type* = 0) 328{ 329} 330 331} // std 332 333#endif // _LIBCPP_EXCEPTION 334