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 #if __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 #else // __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 set_unexpected(unexpected_handler func)48set_unexpected(unexpected_handler func) _NOEXCEPT 49 { 50 return __sync_lock_test_and_set(&__unexpected_handler, func); 51 } 52 53 unexpected_handler get_unexpected()54get_unexpected() _NOEXCEPT 55 { 56 return __sync_fetch_and_add(&__unexpected_handler, (unexpected_handler)0); 57 } 58 59 _LIBCPP_NORETURN 60 void unexpected()61unexpected() 62 { 63 (*get_unexpected())(); 64 // unexpected handler should not return 65 terminate(); 66 } 67 68 terminate_handler set_terminate(terminate_handler func)69set_terminate(terminate_handler func) _NOEXCEPT 70 { 71 return __sync_lock_test_and_set(&__terminate_handler, func); 72 } 73 74 terminate_handler get_terminate()75get_terminate() _NOEXCEPT 76 { 77 return __sync_fetch_and_add(&__terminate_handler, (terminate_handler)0); 78 } 79 80 _LIBCPP_NORETURN 81 void terminate()82terminate() _NOEXCEPT 83 { 84 #ifndef _LIBCPP_NO_EXCEPTIONS 85 try 86 { 87 #endif // _LIBCPP_NO_EXCEPTIONS 88 (*get_terminate())(); 89 // handler should not return 90 ::abort (); 91 #ifndef _LIBCPP_NO_EXCEPTIONS 92 } 93 catch (...) 94 { 95 // handler should not throw exception 96 ::abort (); 97 } 98 #endif // _LIBCPP_NO_EXCEPTIONS 99 } 100 #endif // !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) 101 102 #if !defined(LIBCXXRT) && !defined(__GLIBCXX__) uncaught_exception()103bool uncaught_exception() _NOEXCEPT 104 { 105 #if __APPLE__ || defined(_LIBCPPABI_VERSION) 106 // on Darwin, there is a helper function so __cxa_get_globals is private 107 return __cxa_uncaught_exception(); 108 #else // __APPLE__ 109 #warning uncaught_exception not yet implemented 110 ::abort(); 111 #endif // __APPLE__ 112 } 113 114 #ifndef _LIBCPPABI_VERSION 115 ~exception()116exception::~exception() _NOEXCEPT 117 { 118 } 119 what() const120const char* exception::what() const _NOEXCEPT 121 { 122 return "std::exception"; 123 } 124 125 #endif // _LIBCPPABI_VERSION 126 #endif //LIBCXXRT 127 #if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__) 128 ~bad_exception()129bad_exception::~bad_exception() _NOEXCEPT 130 { 131 } 132 what() const133const char* bad_exception::what() const _NOEXCEPT 134 { 135 return "std::bad_exception"; 136 } 137 138 #endif 139 140 ~exception_ptr()141exception_ptr::~exception_ptr() _NOEXCEPT 142 { 143 #if HAVE_DEPENDENT_EH_ABI 144 __cxa_decrement_exception_refcount(__ptr_); 145 #else 146 #warning exception_ptr not yet implemented 147 ::abort(); 148 #endif // __APPLE__ 149 } 150 exception_ptr(const exception_ptr & other)151exception_ptr::exception_ptr(const exception_ptr& other) _NOEXCEPT 152 : __ptr_(other.__ptr_) 153 { 154 #if HAVE_DEPENDENT_EH_ABI 155 __cxa_increment_exception_refcount(__ptr_); 156 #else 157 #warning exception_ptr not yet implemented 158 ::abort(); 159 #endif // __APPLE__ 160 } 161 operator =(const exception_ptr & other)162exception_ptr& exception_ptr::operator=(const exception_ptr& other) _NOEXCEPT 163 { 164 #if HAVE_DEPENDENT_EH_ABI 165 if (__ptr_ != other.__ptr_) 166 { 167 __cxa_increment_exception_refcount(other.__ptr_); 168 __cxa_decrement_exception_refcount(__ptr_); 169 __ptr_ = other.__ptr_; 170 } 171 return *this; 172 #else // __APPLE__ 173 #warning exception_ptr not yet implemented 174 ::abort(); 175 #endif // __APPLE__ 176 } 177 nested_exception()178nested_exception::nested_exception() _NOEXCEPT 179 : __ptr_(current_exception()) 180 { 181 } 182 ~nested_exception()183nested_exception::~nested_exception() _NOEXCEPT 184 { 185 } 186 187 _LIBCPP_NORETURN 188 void rethrow_nested() const189nested_exception::rethrow_nested() const 190 { 191 if (__ptr_ == nullptr) 192 terminate(); 193 rethrow_exception(__ptr_); 194 } 195 196 current_exception()197exception_ptr current_exception() _NOEXCEPT 198 { 199 #if HAVE_DEPENDENT_EH_ABI 200 // be nicer if there was a constructor that took a ptr, then 201 // this whole function would be just: 202 // return exception_ptr(__cxa_current_primary_exception()); 203 exception_ptr ptr; 204 ptr.__ptr_ = __cxa_current_primary_exception(); 205 return ptr; 206 #else // __APPLE__ 207 #warning exception_ptr not yet implemented 208 ::abort(); 209 #endif // __APPLE__ 210 } 211 212 _LIBCPP_NORETURN rethrow_exception(exception_ptr p)213void rethrow_exception(exception_ptr p) 214 { 215 #if HAVE_DEPENDENT_EH_ABI 216 __cxa_rethrow_primary_exception(p.__ptr_); 217 // if p.__ptr_ is NULL, above returns so we terminate 218 terminate(); 219 #else // __APPLE__ 220 #warning exception_ptr not yet implemented 221 ::abort(); 222 #endif // __APPLE__ 223 } 224 } // std 225