aboutsummaryrefslogtreecommitdiff
path: root/contrib/libc++/src/exception.cpp
blob: 0cd182b716cb1e3f465c3891bd614ff9abca2942 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
//===------------------------ exception.cpp -------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include <stdlib.h>

#include "exception"

#ifndef __has_include
#define __has_include(inc) 0
#endif

#if __APPLE__
  #include <cxxabi.h>

  using namespace __cxxabiv1;
  #define HAVE_DEPENDENT_EH_ABI 1
  #ifndef _LIBCPPABI_VERSION
    using namespace __cxxabiapple;
    // On Darwin, there are two STL shared libraries and a lower level ABI
    // shared libray.  The globals holding the current terminate handler and
    // current unexpected handler are in the ABI library.
    #define __terminate_handler  __cxxabiapple::__cxa_terminate_handler
    #define __unexpected_handler __cxxabiapple::__cxa_unexpected_handler
  #endif  // _LIBCPPABI_VERSION
#elif defined(LIBCXXRT) || __has_include(<cxxabi.h>)
  #include <cxxabi.h>
  using namespace __cxxabiv1;
  #if defined(LIBCXXRT) || defined(_LIBCPPABI_VERSION)
    #define HAVE_DEPENDENT_EH_ABI 1
  #endif
#elif !defined(__GLIBCXX__) // __has_include(<cxxabi.h>)
  static std::terminate_handler  __terminate_handler;
  static std::unexpected_handler __unexpected_handler;
#endif // __has_include(<cxxabi.h>)

namespace std
{

#if !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__)

// libcxxrt provides implementations of these functions itself.
unexpected_handler
set_unexpected(unexpected_handler func) _NOEXCEPT
{
    return __sync_lock_test_and_set(&__unexpected_handler, func);
}

unexpected_handler
get_unexpected() _NOEXCEPT
{
    return __sync_fetch_and_add(&__unexpected_handler, (unexpected_handler)0);
}

_LIBCPP_NORETURN
void
unexpected()
{
    (*get_unexpected())();
    // unexpected handler should not return
    terminate();
}

terminate_handler
set_terminate(terminate_handler func) _NOEXCEPT
{
    return __sync_lock_test_and_set(&__terminate_handler, func);
}

terminate_handler
get_terminate() _NOEXCEPT
{
    return __sync_fetch_and_add(&__terminate_handler, (terminate_handler)0);
}

_LIBCPP_NORETURN
void
terminate() _NOEXCEPT
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif  // _LIBCPP_NO_EXCEPTIONS
        (*get_terminate())();
        // handler should not return
        ::abort ();
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        // handler should not throw exception
        ::abort ();
    }
#endif  // _LIBCPP_NO_EXCEPTIONS
}
#endif // !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION)

#if !defined(LIBCXXRT) && !defined(__GLIBCXX__)
bool uncaught_exception() _NOEXCEPT
{
#if __APPLE__ || defined(_LIBCPPABI_VERSION)
    // on Darwin, there is a helper function so __cxa_get_globals is private
    return __cxa_uncaught_exception();
#else  // __APPLE__
    #warning uncaught_exception not yet implemented
    ::abort();
#endif  // __APPLE__
}

#ifndef _LIBCPPABI_VERSION

exception::~exception() _NOEXCEPT
{
}

const char* exception::what() const _NOEXCEPT
{
  return "std::exception";
}

#endif  // _LIBCPPABI_VERSION
#endif //LIBCXXRT
#if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__)

bad_exception::~bad_exception() _NOEXCEPT
{
}

const char* bad_exception::what() const _NOEXCEPT
{
  return "std::bad_exception";
}

#endif


exception_ptr::~exception_ptr() _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
    __cxa_decrement_exception_refcount(__ptr_);
#else
    #warning exception_ptr not yet implemented
    ::abort();
#endif  // __APPLE__
}

exception_ptr::exception_ptr(const exception_ptr& other) _NOEXCEPT
    : __ptr_(other.__ptr_)
{
#if HAVE_DEPENDENT_EH_ABI
    __cxa_increment_exception_refcount(__ptr_);
#else
    #warning exception_ptr not yet implemented
    ::abort();
#endif  // __APPLE__
}

exception_ptr& exception_ptr::operator=(const exception_ptr& other) _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
    if (__ptr_ != other.__ptr_)
    {
        __cxa_increment_exception_refcount(other.__ptr_);
        __cxa_decrement_exception_refcount(__ptr_);
        __ptr_ = other.__ptr_;
    }
    return *this;
#else  // __APPLE__
    #warning exception_ptr not yet implemented
    ::abort();
#endif  // __APPLE__
}

nested_exception::nested_exception() _NOEXCEPT
    : __ptr_(current_exception())
{
}

nested_exception::~nested_exception() _NOEXCEPT
{
}

_LIBCPP_NORETURN
void
nested_exception::rethrow_nested() const
{
    if (__ptr_ == nullptr)
        terminate();
    rethrow_exception(__ptr_);
}


exception_ptr current_exception() _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
    // be nicer if there was a constructor that took a ptr, then
    // this whole function would be just:
    //    return exception_ptr(__cxa_current_primary_exception());
    exception_ptr ptr;
    ptr.__ptr_ = __cxa_current_primary_exception();
    return ptr;
#else  // __APPLE__
    #warning exception_ptr not yet implemented
    ::abort();
#endif  // __APPLE__
}

_LIBCPP_NORETURN
void rethrow_exception(exception_ptr p)
{
#if HAVE_DEPENDENT_EH_ABI
    __cxa_rethrow_primary_exception(p.__ptr_);
    // if p.__ptr_ is NULL, above returns so we terminate
    terminate();
#else  // __APPLE__
    #warning exception_ptr not yet implemented
    ::abort();
#endif  // __APPLE__
}
} // std