1 //===------------------------ exception.cpp -------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 #include <stdlib.h> 10 11 #include "exception" 12 13 #ifndef __has_include 14 #define __has_include(inc) 0 15 #endif 16 17 #ifdef __APPLE__ 18 #include <cxxabi.h> 19 20 using namespace __cxxabiv1; 21 #define HAVE_DEPENDENT_EH_ABI 1 22 #ifndef _LIBCPPABI_VERSION 23 using namespace __cxxabiapple; 24 // On Darwin, there are two STL shared libraries and a lower level ABI 25 // shared libray. The globals holding the current terminate handler and 26 // current unexpected handler are in the ABI library. 27 #define __terminate_handler __cxxabiapple::__cxa_terminate_handler 28 #define __unexpected_handler __cxxabiapple::__cxa_unexpected_handler 29 #endif // _LIBCPPABI_VERSION 30 #elif defined(LIBCXXRT) || __has_include(<cxxabi.h>) 31 #include <cxxabi.h> 32 using namespace __cxxabiv1; 33 #if defined(LIBCXXRT) || defined(_LIBCPPABI_VERSION) 34 #define HAVE_DEPENDENT_EH_ABI 1 35 #endif 36 #elif !defined(__GLIBCXX__) // __has_include(<cxxabi.h>) 37 static std::terminate_handler __terminate_handler; 38 static std::unexpected_handler __unexpected_handler; 39 #endif // __has_include(<cxxabi.h>) 40 41 namespace std 42 { 43 44 #if !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__) 45 46 // libcxxrt provides implementations of these functions itself. 47 unexpected_handler 48 set_unexpected(unexpected_handler func) _NOEXCEPT 49 { 50 return __sync_lock_test_and_set(&__unexpected_handler, func); 51 } 52 53 unexpected_handler 54 get_unexpected() _NOEXCEPT 55 { 56 return __sync_fetch_and_add(&__unexpected_handler, (unexpected_handler)0); 57 } 58 59 _LIBCPP_NORETURN 60 void 61 unexpected() 62 { 63 (*get_unexpected())(); 64 // unexpected handler should not return 65 terminate(); 66 } 67 68 terminate_handler 69 set_terminate(terminate_handler func) _NOEXCEPT 70 { 71 return __sync_lock_test_and_set(&__terminate_handler, func); 72 } 73 74 terminate_handler 75 get_terminate() _NOEXCEPT 76 { 77 return __sync_fetch_and_add(&__terminate_handler, (terminate_handler)0); 78 } 79 80 #ifndef EMSCRIPTEN // We provide this in JS 81 _LIBCPP_NORETURN 82 void 83 terminate() _NOEXCEPT 84 { 85 #ifndef _LIBCPP_NO_EXCEPTIONS 86 try 87 { 88 #endif // _LIBCPP_NO_EXCEPTIONS 89 (*get_terminate())(); 90 // handler should not return 91 ::abort (); 92 #ifndef _LIBCPP_NO_EXCEPTIONS 93 } 94 catch (...) 95 { 96 // handler should not throw exception 97 ::abort (); 98 } 99 #endif // _LIBCPP_NO_EXCEPTIONS 100 } 101 #endif // !EMSCRIPTEN 102 #endif // !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) 103 104 #if !defined(LIBCXXRT) && !defined(__GLIBCXX__) && !defined(EMSCRIPTEN) 105 bool uncaught_exception() _NOEXCEPT 106 { 107 #if defined(__APPLE__) || defined(_LIBCPPABI_VERSION) 108 // on Darwin, there is a helper function so __cxa_get_globals is private 109 return __cxa_uncaught_exception(); 110 #else // __APPLE__ 111 #warning uncaught_exception not yet implemented 112 ::abort(); 113 #endif // __APPLE__ 114 } 115 116 #ifndef _LIBCPPABI_VERSION 117 118 exception::~exception() _NOEXCEPT 119 { 120 } 121 122 const char* exception::what() const _NOEXCEPT 123 { 124 return "std::exception"; 125 } 126 127 #endif // _LIBCPPABI_VERSION 128 #endif //LIBCXXRT 129 #if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__) 130 131 bad_exception::~bad_exception() _NOEXCEPT 132 { 133 } 134 135 const char* bad_exception::what() const _NOEXCEPT 136 { 137 return "std::bad_exception"; 138 } 139 140 #endif 141 142 143 exception_ptr::~exception_ptr() _NOEXCEPT 144 { 145 #if HAVE_DEPENDENT_EH_ABI 146 __cxa_decrement_exception_refcount(__ptr_); 147 #else 148 #warning exception_ptr not yet implemented 149 ::abort(); 150 #endif // __APPLE__ 151 } 152 153 exception_ptr::exception_ptr(const exception_ptr& other) _NOEXCEPT 154 : __ptr_(other.__ptr_) 155 { 156 #if HAVE_DEPENDENT_EH_ABI 157 __cxa_increment_exception_refcount(__ptr_); 158 #else 159 #warning exception_ptr not yet implemented 160 ::abort(); 161 #endif // __APPLE__ 162 } 163 164 exception_ptr& exception_ptr::operator=(const exception_ptr& other) _NOEXCEPT 165 { 166 #if HAVE_DEPENDENT_EH_ABI 167 if (__ptr_ != other.__ptr_) 168 { 169 __cxa_increment_exception_refcount(other.__ptr_); 170 __cxa_decrement_exception_refcount(__ptr_); 171 __ptr_ = other.__ptr_; 172 } 173 return *this; 174 #else // __APPLE__ 175 #warning exception_ptr not yet implemented 176 ::abort(); 177 #endif // __APPLE__ 178 } 179 180 nested_exception::nested_exception() _NOEXCEPT 181 : __ptr_(current_exception()) 182 { 183 } 184 185 nested_exception::~nested_exception() _NOEXCEPT 186 { 187 } 188 189 _LIBCPP_NORETURN 190 void 191 nested_exception::rethrow_nested() const 192 { 193 if (__ptr_ == nullptr) 194 terminate(); 195 rethrow_exception(__ptr_); 196 } 197 198 199 exception_ptr current_exception() _NOEXCEPT 200 { 201 #if HAVE_DEPENDENT_EH_ABI 202 // be nicer if there was a constructor that took a ptr, then 203 // this whole function would be just: 204 // return exception_ptr(__cxa_current_primary_exception()); 205 exception_ptr ptr; 206 ptr.__ptr_ = __cxa_current_primary_exception(); 207 return ptr; 208 #else // __APPLE__ 209 #warning exception_ptr not yet implemented 210 ::abort(); 211 #endif // __APPLE__ 212 } 213 214 _LIBCPP_NORETURN 215 void rethrow_exception(exception_ptr p) 216 { 217 #if HAVE_DEPENDENT_EH_ABI 218 __cxa_rethrow_primary_exception(p.__ptr_); 219 // if p.__ptr_ is NULL, above returns so we terminate 220 terminate(); 221 #else // __APPLE__ 222 #warning exception_ptr not yet implemented 223 ::abort(); 224 #endif // __APPLE__ 225 } 226 } // std 227