1/*
2 * Copyright 2016-present Facebook, Inc.
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#pragma once
18
19#include <exception>
20#include <string>
21#include <type_traits>
22
23#include <folly/Demangle.h>
24#include <folly/FBString.h>
25#include <folly/Portability.h>
26
27namespace folly {
28
29/**
30 * Debug string for an exception: include type and what(), if
31 * defined.
32 */
33inline fbstring exceptionStr(const std::exception& e) {
34#ifdef FOLLY_HAS_RTTI
35 fbstring rv(demangle(typeid(e)));
36 rv += ": ";
37#else
38 fbstring rv("Exception (no RTTI available): ");
39#endif
40 rv += e.what();
41 return rv;
42}
43
44// Empirically, this indicates if the runtime supports
45// std::exception_ptr, as not all (arm, for instance) do.
46#if defined(__GNUC__) && defined(__GCC_ATOMIC_INT_LOCK_FREE) && \
47 __GCC_ATOMIC_INT_LOCK_FREE > 1
48inline fbstring exceptionStr(std::exception_ptr ep) {
49 if (!kHasExceptions) {
50 return "Exception (catch unavailable)";
51 }
52 return catch_exception(
53 [&]() -> fbstring {
54 return catch_exception<std::exception const&>(
55 [&]() -> fbstring {
56 std::rethrow_exception(ep);
57 assume_unreachable();
58 },
59 [](auto&& e) { return exceptionStr(e); });
60 },
61 []() -> fbstring { return "<unknown exception>"; });
62}
63#endif
64
65template <typename E>
66auto exceptionStr(const E& e) -> typename std::
67 enable_if<!std::is_base_of<std::exception, E>::value, fbstring>::type {
68#ifdef FOLLY_HAS_RTTI
69 return demangle(typeid(e));
70#else
71 (void)e;
72 return "Exception (no RTTI available)";
73#endif
74}
75
76} // namespace folly
77