1/*
2 * Copyright (c) Facebook, Inc. and its affiliates.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <folly/ExceptionWrapper.h>
18
19#include <iostream>
20
21#include <folly/GLog.h>
22
23namespace folly {
24
25exception_wrapper::VTable const exception_wrapper::uninit_{
26 &noop_<void, exception_wrapper const*, exception_wrapper*>,
27 &noop_<void, exception_wrapper*, exception_wrapper*>,
28 &noop_<void, exception_wrapper*>,
29 &noop_<void, exception_wrapper const*>,
30 &uninit_type_,
31 &noop_<std::exception const*, exception_wrapper const*>,
32 &noop_<exception_wrapper, exception_wrapper const*>};
33
34exception_wrapper::VTable const exception_wrapper::ExceptionPtr::ops_{
35 copy_,
36 move_,
37 delete_,
38 throw_,
39 type_,
40 get_exception_,
41 get_exception_ptr_};
42
43exception_wrapper::VTable const exception_wrapper::SharedPtr::ops_{
44 copy_,
45 move_,
46 delete_,
47 throw_,
48 type_,
49 get_exception_,
50 get_exception_ptr_};
51
52namespace {
53std::exception const* get_std_exception_(std::exception_ptr eptr) noexcept {
54 try {
55 std::rethrow_exception(eptr);
56 } catch (const std::exception& ex) {
57 return &ex;
58 } catch (...) {
59 return nullptr;
60 }
61}
62} // namespace
63
64exception_wrapper exception_wrapper::from_exception_ptr(
65 std::exception_ptr const& ptr) noexcept {
66 if (!ptr) {
67 return exception_wrapper();
68 }
69 try {
70 std::rethrow_exception(ptr);
71 } catch (std::exception& e) {
72 return exception_wrapper(std::current_exception(), e);
73 } catch (...) {
74 return exception_wrapper(std::current_exception());
75 }
76}
77
78exception_wrapper::exception_wrapper(std::exception_ptr ptr) noexcept
79 : exception_wrapper{} {
80 if (ptr) {
81 if (auto e = get_std_exception_(ptr)) {
82 LOG(DFATAL)
83 << "Performance error: Please construct exception_wrapper with a "
84 "reference to the std::exception along with the "
85 "std::exception_ptr.";
86 *this = exception_wrapper{std::move(ptr), *e};
87 } else {
88 Unknown uk;
89 *this = exception_wrapper{ptr, uk};
90 }
91 }
92}
93
94[[noreturn]] void exception_wrapper::onNoExceptionError(
95 char const* const name) {
96 std::ios_base::Init ioinit_; // ensure std::cerr is alive
97 std::cerr << "Cannot use `" << name
98 << "` with an empty folly::exception_wrapper" << std::endl;
99 std::terminate();
100}
101
102fbstring exceptionStr(exception_wrapper const& ew) {
103 return ew.what();
104}
105
106} // namespace folly
107