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#include <stdio.h> 11 12#include "exception" 13#include "new" 14 15#if defined(__APPLE__) && !defined(LIBCXXRT) 16 #include <cxxabi.h> 17 18 using namespace __cxxabiv1; 19 #define HAVE_DEPENDENT_EH_ABI 1 20 #ifndef _LIBCPPABI_VERSION 21 using namespace __cxxabiapple; 22 // On Darwin, there are two STL shared libraries and a lower level ABI 23 // shared library. The globals holding the current terminate handler and 24 // current unexpected handler are in the ABI library. 25 #define __terminate_handler __cxxabiapple::__cxa_terminate_handler 26 #define __unexpected_handler __cxxabiapple::__cxa_unexpected_handler 27 #endif // _LIBCPPABI_VERSION 28#elif defined(LIBCXXRT) || defined(LIBCXX_BUILDING_LIBCXXABI) 29 #include <cxxabi.h> 30 using namespace __cxxabiv1; 31 #if defined(LIBCXXRT) || defined(_LIBCPPABI_VERSION) 32 #define HAVE_DEPENDENT_EH_ABI 1 33 #endif 34#elif !defined(__GLIBCXX__) // defined(LIBCXX_BUILDING_LIBCXXABI) 35 static std::terminate_handler __terminate_handler; 36 static std::unexpected_handler __unexpected_handler; 37#endif // defined(LIBCXX_BUILDING_LIBCXXABI) 38 39namespace std 40{ 41 42#if !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__) 43 44// libcxxrt provides implementations of these functions itself. 45unexpected_handler 46set_unexpected(unexpected_handler func) _NOEXCEPT 47{ 48 return __sync_lock_test_and_set(&__unexpected_handler, func); 49} 50 51unexpected_handler 52get_unexpected() _NOEXCEPT 53{ 54 return __sync_fetch_and_add(&__unexpected_handler, (unexpected_handler)0); 55} 56 57_LIBCPP_NORETURN 58void 59unexpected() 60{ 61 (*get_unexpected())(); 62 // unexpected handler should not return 63 terminate(); 64} 65 66terminate_handler 67set_terminate(terminate_handler func) _NOEXCEPT 68{ 69 return __sync_lock_test_and_set(&__terminate_handler, func); 70} 71 72terminate_handler 73get_terminate() _NOEXCEPT 74{ 75 return __sync_fetch_and_add(&__terminate_handler, (terminate_handler)0); 76} 77 78#ifndef __EMSCRIPTEN__ // We provide this in JS 79_LIBCPP_NORETURN 80void 81terminate() _NOEXCEPT 82{ 83#ifndef _LIBCPP_NO_EXCEPTIONS 84 try 85 { 86#endif // _LIBCPP_NO_EXCEPTIONS 87 (*get_terminate())(); 88 // handler should not return 89 fprintf(stderr, "terminate_handler unexpectedly returned\n"); 90 ::abort(); 91#ifndef _LIBCPP_NO_EXCEPTIONS 92 } 93 catch (...) 94 { 95 // handler should not throw exception 96 fprintf(stderr, "terminate_handler unexpectedly threw an exception\n"); 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__) 105bool uncaught_exception() _NOEXCEPT { return uncaught_exceptions() > 0; } 106 107int uncaught_exceptions() _NOEXCEPT 108{ 109#if defined(__APPLE__) || defined(_LIBCPPABI_VERSION) 110 // on Darwin, there is a helper function so __cxa_get_globals is private 111# if _LIBCPPABI_VERSION > 1101 112 return __cxa_uncaught_exceptions(); 113# else 114 return __cxa_uncaught_exception() ? 1 : 0; 115# endif 116#else // __APPLE__ 117# if defined(_MSC_VER) && ! defined(__clang__) 118 _LIBCPP_WARNING("uncaught_exceptions not yet implemented") 119# else 120# warning uncaught_exception not yet implemented 121# endif 122 fprintf(stderr, "uncaught_exceptions not yet implemented\n"); 123 ::abort(); 124#endif // __APPLE__ 125} 126 127 128#ifndef _LIBCPPABI_VERSION 129 130exception::~exception() _NOEXCEPT 131{ 132} 133 134const char* exception::what() const _NOEXCEPT 135{ 136 return "std::exception"; 137} 138 139#endif // _LIBCPPABI_VERSION 140#endif //LIBCXXRT 141#if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__) 142 143bad_exception::~bad_exception() _NOEXCEPT 144{ 145} 146 147const char* bad_exception::what() const _NOEXCEPT 148{ 149 return "std::bad_exception"; 150} 151 152#endif 153 154#if defined(__GLIBCXX__) 155 156// libsupc++ does not implement the dependent EH ABI and the functionality 157// it uses to implement std::exception_ptr (which it declares as an alias of 158// std::__exception_ptr::exception_ptr) is not directly exported to clients. So 159// we have little choice but to hijack std::__exception_ptr::exception_ptr's 160// (which fortunately has the same layout as our std::exception_ptr) copy 161// constructor, assignment operator and destructor (which are part of its 162// stable ABI), and its rethrow_exception(std::__exception_ptr::exception_ptr) 163// function. 164 165namespace __exception_ptr 166{ 167 168struct exception_ptr 169{ 170 void* __ptr_; 171 172 exception_ptr(const exception_ptr&) _NOEXCEPT; 173 exception_ptr& operator=(const exception_ptr&) _NOEXCEPT; 174 ~exception_ptr() _NOEXCEPT; 175}; 176 177} 178 179_LIBCPP_NORETURN void rethrow_exception(__exception_ptr::exception_ptr); 180 181#endif 182 183exception_ptr::~exception_ptr() _NOEXCEPT 184{ 185#if HAVE_DEPENDENT_EH_ABI 186 __cxa_decrement_exception_refcount(__ptr_); 187#elif defined(__GLIBCXX__) 188 reinterpret_cast<__exception_ptr::exception_ptr*>(this)->~exception_ptr(); 189#else 190# if defined(_MSC_VER) && ! defined(__clang__) 191 _LIBCPP_WARNING("exception_ptr not yet implemented") 192# else 193# warning exception_ptr not yet implemented 194# endif 195 fprintf(stderr, "exception_ptr not yet implemented\n"); 196 ::abort(); 197#endif 198} 199 200exception_ptr::exception_ptr(const exception_ptr& other) _NOEXCEPT 201 : __ptr_(other.__ptr_) 202{ 203#if HAVE_DEPENDENT_EH_ABI 204 __cxa_increment_exception_refcount(__ptr_); 205#elif defined(__GLIBCXX__) 206 new (reinterpret_cast<void*>(this)) __exception_ptr::exception_ptr( 207 reinterpret_cast<const __exception_ptr::exception_ptr&>(other)); 208#else 209# if defined(_MSC_VER) && ! defined(__clang__) 210 _LIBCPP_WARNING("exception_ptr not yet implemented") 211# else 212# warning exception_ptr not yet implemented 213# endif 214 fprintf(stderr, "exception_ptr not yet implemented\n"); 215 ::abort(); 216#endif 217} 218 219exception_ptr& exception_ptr::operator=(const exception_ptr& other) _NOEXCEPT 220{ 221#if HAVE_DEPENDENT_EH_ABI 222 if (__ptr_ != other.__ptr_) 223 { 224 __cxa_increment_exception_refcount(other.__ptr_); 225 __cxa_decrement_exception_refcount(__ptr_); 226 __ptr_ = other.__ptr_; 227 } 228 return *this; 229#elif defined(__GLIBCXX__) 230 *reinterpret_cast<__exception_ptr::exception_ptr*>(this) = 231 reinterpret_cast<const __exception_ptr::exception_ptr&>(other); 232 return *this; 233#else 234# if defined(_MSC_VER) && ! defined(__clang__) 235 _LIBCPP_WARNING("exception_ptr not yet implemented") 236# else 237# warning exception_ptr not yet implemented 238# endif 239 fprintf(stderr, "exception_ptr not yet implemented\n"); 240 ::abort(); 241#endif 242} 243 244nested_exception::nested_exception() _NOEXCEPT 245 : __ptr_(current_exception()) 246{ 247} 248 249#if !defined(__GLIBCXX__) 250 251nested_exception::~nested_exception() _NOEXCEPT 252{ 253} 254 255#endif 256 257_LIBCPP_NORETURN 258void 259nested_exception::rethrow_nested() const 260{ 261 if (__ptr_ == nullptr) 262 terminate(); 263 rethrow_exception(__ptr_); 264} 265 266#if !defined(__GLIBCXX__) 267 268exception_ptr current_exception() _NOEXCEPT 269{ 270#if HAVE_DEPENDENT_EH_ABI 271 // be nicer if there was a constructor that took a ptr, then 272 // this whole function would be just: 273 // return exception_ptr(__cxa_current_primary_exception()); 274 exception_ptr ptr; 275 ptr.__ptr_ = __cxa_current_primary_exception(); 276 return ptr; 277#else 278# if defined(_MSC_VER) && ! defined(__clang__) 279 _LIBCPP_WARNING( "exception_ptr not yet implemented" ) 280# else 281# warning exception_ptr not yet implemented 282# endif 283 fprintf(stderr, "exception_ptr not yet implemented\n"); 284 ::abort(); 285#endif 286} 287 288#endif // !__GLIBCXX__ 289 290_LIBCPP_NORETURN 291void rethrow_exception(exception_ptr p) 292{ 293#if HAVE_DEPENDENT_EH_ABI 294 __cxa_rethrow_primary_exception(p.__ptr_); 295 // if p.__ptr_ is NULL, above returns so we terminate 296 terminate(); 297#elif defined(__GLIBCXX__) 298 rethrow_exception(reinterpret_cast<__exception_ptr::exception_ptr&>(p)); 299#else 300# if defined(_MSC_VER) && ! defined(__clang__) 301 _LIBCPP_WARNING("exception_ptr not yet implemented") 302# else 303# warning exception_ptr not yet implemented 304# endif 305 fprintf(stderr, "exception_ptr not yet implemented\n"); 306 ::abort(); 307#endif 308} 309} // std 310