1
2 /**
3 * Copyright (C) 2018-present MongoDB, Inc.
4 *
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the Server Side Public License, version 1,
7 * as published by MongoDB, Inc.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * Server Side Public License for more details.
13 *
14 * You should have received a copy of the Server Side Public License
15 * along with this program. If not, see
16 * <http://www.mongodb.com/licensing/server-side-public-license>.
17 *
18 * As a special exception, the copyright holders give permission to link the
19 * code of portions of this program with the OpenSSL library under certain
20 * conditions as described in each individual source file and distribute
21 * linked combinations including the program with the OpenSSL library. You
22 * must comply with the Server Side Public License in all respects for
23 * all of the code used other than as permitted herein. If you modify file(s)
24 * with this exception, you may extend this exception to your version of the
25 * file(s), but you are not obligated to do so. If you do not wish to do so,
26 * delete this exception statement from your version. If you delete this
27 * exception statement from all source files in the program, then also delete
28 * it in the license file.
29 */
30
31 #include "mongo/platform/basic.h"
32
33 #include <string>
34
35 #include "mongo/base/system_error.h"
36
37 namespace mongo {
38
39 namespace {
40
41 /**
42 * A std::error_category for the codes in the named ErrorCodes space.
43 */
44 class MongoErrorCategoryImpl final : public std::error_category {
45 public:
46 MongoErrorCategoryImpl() = default;
47
name() const48 const char* name() const noexcept override {
49 return "mongo";
50 }
51
message(int ev) const52 std::string message(int ev) const override {
53 return ErrorCodes::errorString(ErrorCodes::Error(ev));
54 }
55
56 // We don't really want to override this function, but to override the second we need to,
57 // otherwise there will be issues with overload resolution.
equivalent(const int code,const std::error_condition & condition) const58 bool equivalent(const int code, const std::error_condition& condition) const noexcept override {
59 return std::error_category::equivalent(code, condition);
60 }
61
equivalent(const std::error_code & code,int condition) const62 bool equivalent(const std::error_code& code, int condition) const noexcept override {
63 switch (ErrorCodes::Error(condition)) {
64 case ErrorCodes::OK:
65 // Make ErrorCodes::OK to be equivalent to the default constructed error code.
66 return code == std::error_code();
67 default:
68 return false;
69 }
70 }
71 };
72
73 } // namespace
74
mongoErrorCategory()75 const std::error_category& mongoErrorCategory() {
76 // TODO: Remove this static, and make a constexpr instance when we move to C++14.
77 static const MongoErrorCategoryImpl instance{};
78 return instance;
79 }
80
make_error_code(ErrorCodes::Error code)81 std::error_code make_error_code(ErrorCodes::Error code) {
82 return std::error_code(ErrorCodes::Error(code), mongoErrorCategory());
83 }
84
make_error_condition(ErrorCodes::Error code)85 std::error_condition make_error_condition(ErrorCodes::Error code) {
86 return std::error_condition(ErrorCodes::Error(code), mongoErrorCategory());
87 }
88
89 } // namespace mongo
90