1 // -*- C++ -*- 2 //===-------------------------- exception ---------------------------------===// 3 // 4 // The LLVM Compiler Infrastructure 5 // 6 // This file is dual licensed under the MIT and the University of Illinois Open 7 // Source Licenses. See LICENSE.TXT for details. 8 // 9 //===----------------------------------------------------------------------===// 10 11 #ifndef _LIBCPP_EXCEPTION 12 #define _LIBCPP_EXCEPTION 13 14 /* 15 exception synopsis 16 17 namespace std 18 { 19 20 class exception 21 { 22 public: 23 exception() noexcept; 24 exception(const exception&) noexcept; 25 exception& operator=(const exception&) noexcept; 26 virtual ~exception() noexcept; 27 virtual const char* what() const noexcept; 28 }; 29 30 class bad_exception 31 : public exception 32 { 33 public: 34 bad_exception() noexcept; 35 bad_exception(const bad_exception&) noexcept; 36 bad_exception& operator=(const bad_exception&) noexcept; 37 virtual ~bad_exception() noexcept; 38 virtual const char* what() const noexcept; 39 }; 40 41 typedef void (*unexpected_handler)(); 42 unexpected_handler set_unexpected(unexpected_handler f ) noexcept; 43 unexpected_handler get_unexpected() noexcept; 44 [[noreturn]] void unexpected(); 45 46 typedef void (*terminate_handler)(); 47 terminate_handler set_terminate(terminate_handler f ) noexcept; 48 terminate_handler get_terminate() noexcept; 49 [[noreturn]] void terminate() noexcept; 50 51 bool uncaught_exception() noexcept; 52 int uncaught_exceptions() noexcept; // C++17 53 54 typedef unspecified exception_ptr; 55 56 exception_ptr current_exception() noexcept; 57 void rethrow_exception [[noreturn]] (exception_ptr p); 58 template<class E> exception_ptr make_exception_ptr(E e) noexcept; 59 60 class nested_exception 61 { 62 public: 63 nested_exception() noexcept; 64 nested_exception(const nested_exception&) noexcept = default; 65 nested_exception& operator=(const nested_exception&) noexcept = default; 66 virtual ~nested_exception() = default; 67 68 // access functions 69 [[noreturn]] void rethrow_nested() const; 70 exception_ptr nested_ptr() const noexcept; 71 }; 72 73 template <class T> [[noreturn]] void throw_with_nested(T&& t); 74 template <class E> void rethrow_if_nested(const E& e); 75 76 } // std 77 78 */ 79 80 #include <__config> 81 #include <cstddef> 82 #include <cstdlib> 83 #include <type_traits> 84 85 #if defined(_LIBCPP_ABI_MICROSOFT) 86 #include <vcruntime_exception.h> 87 #endif 88 89 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 90 #pragma GCC system_header 91 #endif 92 93 namespace std // purposefully not using versioning namespace 94 { 95 96 #if !defined(_LIBCPP_ABI_MICROSOFT) 97 class _LIBCPP_EXCEPTION_ABI exception 98 { 99 public: 100 _LIBCPP_INLINE_VISIBILITY exception() _NOEXCEPT {} 101 virtual ~exception() _NOEXCEPT; 102 virtual const char* what() const _NOEXCEPT; 103 }; 104 105 class _LIBCPP_EXCEPTION_ABI bad_exception 106 : public exception 107 { 108 public: 109 _LIBCPP_INLINE_VISIBILITY bad_exception() _NOEXCEPT {} 110 virtual ~bad_exception() _NOEXCEPT; 111 virtual const char* what() const _NOEXCEPT; 112 }; 113 #endif // !_LIBCPP_ABI_MICROSOFT 114 115 #if _LIBCPP_STD_VER <= 14 \ 116 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS) \ 117 || defined(_LIBCPP_BUILDING_LIBRARY) 118 typedef void (*unexpected_handler)(); 119 _LIBCPP_FUNC_VIS unexpected_handler set_unexpected(unexpected_handler) _NOEXCEPT; 120 _LIBCPP_FUNC_VIS unexpected_handler get_unexpected() _NOEXCEPT; 121 _LIBCPP_NORETURN _LIBCPP_FUNC_VIS void unexpected(); 122 #endif 123 124 typedef void (*terminate_handler)(); 125 _LIBCPP_FUNC_VIS terminate_handler set_terminate(terminate_handler) _NOEXCEPT; 126 _LIBCPP_FUNC_VIS terminate_handler get_terminate() _NOEXCEPT; 127 _LIBCPP_NORETURN _LIBCPP_FUNC_VIS void terminate() _NOEXCEPT; 128 129 _LIBCPP_FUNC_VIS bool uncaught_exception() _NOEXCEPT; 130 _LIBCPP_FUNC_VIS int uncaught_exceptions() _NOEXCEPT; 131 132 class _LIBCPP_TYPE_VIS exception_ptr; 133 134 _LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT; 135 _LIBCPP_NORETURN _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr); 136 137 class _LIBCPP_TYPE_VIS exception_ptr 138 { 139 void* __ptr_; 140 public: 141 _LIBCPP_INLINE_VISIBILITY exception_ptr() _NOEXCEPT : __ptr_() {} 142 _LIBCPP_INLINE_VISIBILITY exception_ptr(nullptr_t) _NOEXCEPT : __ptr_() {} 143 exception_ptr(const exception_ptr&) _NOEXCEPT; 144 exception_ptr& operator=(const exception_ptr&) _NOEXCEPT; 145 ~exception_ptr() _NOEXCEPT; 146 147 _LIBCPP_INLINE_VISIBILITY 148 _LIBCPP_EXPLICIT 149 operator bool() const _NOEXCEPT {return __ptr_ != nullptr;} 150 151 friend _LIBCPP_INLINE_VISIBILITY 152 bool operator==(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT 153 {return __x.__ptr_ == __y.__ptr_;} 154 friend _LIBCPP_INLINE_VISIBILITY 155 bool operator!=(const exception_ptr& __x, const exception_ptr& __y) _NOEXCEPT 156 {return !(__x == __y);} 157 158 friend _LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT; 159 friend _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr); 160 }; 161 162 template<class _Ep> 163 exception_ptr 164 make_exception_ptr(_Ep __e) _NOEXCEPT 165 { 166 #ifndef _LIBCPP_NO_EXCEPTIONS 167 try 168 { 169 throw __e; 170 } 171 catch (...) 172 { 173 return current_exception(); 174 } 175 #else 176 ((void)__e); 177 _VSTD::abort(); 178 #endif 179 } 180 181 // nested_exception 182 183 class _LIBCPP_EXCEPTION_ABI nested_exception 184 { 185 exception_ptr __ptr_; 186 public: 187 nested_exception() _NOEXCEPT; 188 // nested_exception(const nested_exception&) noexcept = default; 189 // nested_exception& operator=(const nested_exception&) noexcept = default; 190 virtual ~nested_exception() _NOEXCEPT; 191 192 // access functions 193 _LIBCPP_NORETURN void rethrow_nested() const; 194 _LIBCPP_INLINE_VISIBILITY exception_ptr nested_ptr() const _NOEXCEPT {return __ptr_;} 195 }; 196 197 template <class _Tp> 198 struct __nested 199 : public _Tp, 200 public nested_exception 201 { 202 _LIBCPP_INLINE_VISIBILITY explicit __nested(const _Tp& __t) : _Tp(__t) {} 203 }; 204 205 template <class _Tp> 206 _LIBCPP_NORETURN 207 void 208 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 209 throw_with_nested(_Tp&& __t, typename enable_if< 210 is_class<typename remove_reference<_Tp>::type>::value && 211 !is_base_of<nested_exception, typename remove_reference<_Tp>::type>::value 212 && !__libcpp_is_final<typename remove_reference<_Tp>::type>::value 213 >::type* = 0) 214 #else // _LIBCPP_HAS_NO_RVALUE_REFERENCES 215 throw_with_nested (_Tp& __t, typename enable_if< 216 is_class<_Tp>::value && !is_base_of<nested_exception, _Tp>::value 217 >::type* = 0) 218 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 219 { 220 #ifndef _LIBCPP_NO_EXCEPTIONS 221 throw __nested<typename remove_reference<_Tp>::type>(_VSTD::forward<_Tp>(__t)); 222 #else 223 ((void)__t); 224 // FIXME: Make this abort. 225 #endif 226 } 227 228 template <class _Tp> 229 _LIBCPP_NORETURN 230 void 231 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 232 throw_with_nested(_Tp&& __t, typename enable_if< 233 !is_class<typename remove_reference<_Tp>::type>::value || 234 is_base_of<nested_exception, typename remove_reference<_Tp>::type>::value 235 || __libcpp_is_final<typename remove_reference<_Tp>::type>::value 236 >::type* = 0) 237 #else // _LIBCPP_HAS_NO_RVALUE_REFERENCES 238 throw_with_nested (_Tp& __t, typename enable_if< 239 !is_class<_Tp>::value || is_base_of<nested_exception, _Tp>::value 240 >::type* = 0) 241 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 242 { 243 #ifndef _LIBCPP_NO_EXCEPTIONS 244 throw _VSTD::forward<_Tp>(__t); 245 #else 246 ((void)__t); 247 // FIXME: Make this abort 248 #endif 249 } 250 251 template <class _From, class _To> 252 struct __can_dynamic_cast : public _LIBCPP_BOOL_CONSTANT( 253 is_polymorphic<_From>::value && 254 (!is_base_of<_To, _From>::value || 255 is_convertible<const _From*, const _To*>::value)) {}; 256 257 template <class _Ep> 258 inline _LIBCPP_INLINE_VISIBILITY 259 void 260 rethrow_if_nested(const _Ep& __e, 261 typename enable_if< __can_dynamic_cast<_Ep, nested_exception>::value>::type* = 0) 262 { 263 const nested_exception* __nep = dynamic_cast<const nested_exception*>(_VSTD::addressof(__e)); 264 if (__nep) 265 __nep->rethrow_nested(); 266 } 267 268 template <class _Ep> 269 inline _LIBCPP_INLINE_VISIBILITY 270 void 271 rethrow_if_nested(const _Ep&, 272 typename enable_if<!__can_dynamic_cast<_Ep, nested_exception>::value>::type* = 0) 273 { 274 } 275 276 } // std 277 278 #endif // _LIBCPP_EXCEPTION 279