1 //===------------------------- cxa_handlers.cpp ---------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 // 8 // This file implements the functionality associated with the terminate_handler, 9 // unexpected_handler, and new_handler. 10 //===----------------------------------------------------------------------===// 11 12 #include <stdexcept> 13 #include <new> 14 #include <exception> 15 #include "abort_message.h" 16 #include "cxxabi.h" 17 #include "cxa_handlers.h" 18 #include "cxa_exception.h" 19 #include "private_typeinfo.h" 20 #include "include/atomic_support.h" 21 22 namespace std 23 { 24 25 unexpected_handler get_unexpected()26get_unexpected() _NOEXCEPT 27 { 28 return __libcpp_atomic_load(&__cxa_unexpected_handler, _AO_Acquire); 29 } 30 31 void __unexpected(unexpected_handler func)32__unexpected(unexpected_handler func) 33 { 34 func(); 35 // unexpected handler should not return 36 abort_message("unexpected_handler unexpectedly returned"); 37 } 38 39 __attribute__((noreturn)) 40 void unexpected()41unexpected() 42 { 43 __unexpected(get_unexpected()); 44 } 45 46 terminate_handler get_terminate()47get_terminate() _NOEXCEPT 48 { 49 return __libcpp_atomic_load(&__cxa_terminate_handler, _AO_Acquire); 50 } 51 52 void __terminate(terminate_handler func)53__terminate(terminate_handler func) _NOEXCEPT 54 { 55 #ifndef _LIBCXXABI_NO_EXCEPTIONS 56 try 57 { 58 #endif // _LIBCXXABI_NO_EXCEPTIONS 59 func(); 60 // handler should not return 61 abort_message("terminate_handler unexpectedly returned"); 62 #ifndef _LIBCXXABI_NO_EXCEPTIONS 63 } 64 catch (...) 65 { 66 // handler should not throw exception 67 abort_message("terminate_handler unexpectedly threw an exception"); 68 } 69 #endif // _LIBCXXABI_NO_EXCEPTIONS 70 } 71 72 __attribute__((noreturn)) 73 void terminate()74terminate() _NOEXCEPT 75 { 76 #ifndef _LIBCXXABI_NO_EXCEPTIONS 77 // If there might be an uncaught exception 78 using namespace __cxxabiv1; 79 __cxa_eh_globals* globals = __cxa_get_globals_fast(); 80 if (globals) 81 { 82 __cxa_exception* exception_header = globals->caughtExceptions; 83 if (exception_header) 84 { 85 _Unwind_Exception* unwind_exception = 86 reinterpret_cast<_Unwind_Exception*>(exception_header + 1) - 1; 87 if (__isOurExceptionClass(unwind_exception)) 88 __terminate(exception_header->terminateHandler); 89 } 90 } 91 #endif 92 __terminate(get_terminate()); 93 } 94 95 extern "C" { 96 new_handler __cxa_new_handler = 0; 97 } 98 99 new_handler set_new_handler(new_handler handler)100set_new_handler(new_handler handler) _NOEXCEPT 101 { 102 return __libcpp_atomic_exchange(&__cxa_new_handler, handler, _AO_Acq_Rel); 103 } 104 105 new_handler get_new_handler()106get_new_handler() _NOEXCEPT 107 { 108 return __libcpp_atomic_load(&__cxa_new_handler, _AO_Acquire); 109 } 110 111 } // std 112