• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===------------------------- cxa_handlers.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 // This file implements the functionality associated with the terminate_handler,
10 //   unexpected_handler, and new_handler.
11 //===----------------------------------------------------------------------===//
12 
13 #include <stdexcept>
14 #include <new>
15 #include <exception>
16 #include "abort_message.h"
17 #include "cxxabi.h"
18 #include "cxa_handlers.hpp"
19 #include "cxa_exception.hpp"
20 #include "private_typeinfo.h"
21 #include "include/atomic_support.h"
22 
23 namespace std
24 {
25 
26 unexpected_handler
get_unexpected()27 get_unexpected() _NOEXCEPT
28 {
29     return __libcpp_atomic_load(&__cxa_unexpected_handler, _AO_Acquire);
30 }
31 
32 void
__unexpected(unexpected_handler func)33 __unexpected(unexpected_handler func)
34 {
35     func();
36     // unexpected handler should not return
37     abort_message("unexpected_handler unexpectedly returned");
38 }
39 
40 __attribute__((noreturn))
41 void
unexpected()42 unexpected()
43 {
44     __unexpected(get_unexpected());
45 }
46 
47 terminate_handler
get_terminate()48 get_terminate() _NOEXCEPT
49 {
50     return __libcpp_atomic_load(&__cxa_terminate_handler, _AO_Acquire);
51 }
52 
53 void
__terminate(terminate_handler func)54 __terminate(terminate_handler func) _NOEXCEPT
55 {
56 #ifndef _LIBCXXABI_NO_EXCEPTIONS
57     try
58     {
59 #endif  // _LIBCXXABI_NO_EXCEPTIONS
60         func();
61         // handler should not return
62         abort_message("terminate_handler unexpectedly returned");
63 #ifndef _LIBCXXABI_NO_EXCEPTIONS
64     }
65     catch (...)
66     {
67         // handler should not throw exception
68         abort_message("terminate_handler unexpectedly threw an exception");
69     }
70 #endif  // _LIBCXXABI_NO_EXCEPTIONS
71 }
72 
73 __attribute__((noreturn))
74 void
terminate()75 terminate() _NOEXCEPT
76 {
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     __terminate(get_terminate());
92 }
93 
94 extern "C" {
95 new_handler __cxa_new_handler = 0;
96 }
97 
98 new_handler
set_new_handler(new_handler handler)99 set_new_handler(new_handler handler) _NOEXCEPT
100 {
101     return __libcpp_atomic_exchange(&__cxa_new_handler, handler, _AO_Acq_Rel);
102 }
103 
104 new_handler
get_new_handler()105 get_new_handler() _NOEXCEPT
106 {
107     return __libcpp_atomic_load(&__cxa_new_handler, _AO_Acquire);
108 }
109 
110 }  // std
111