1fa7767c5Sopenharmony_ci/*
2fa7767c5Sopenharmony_ci * Copyright (C) 2021 Huawei Device Co., Ltd.
3fa7767c5Sopenharmony_ci * Licensed under the Apache License, Version 2.0 (the "License");
4fa7767c5Sopenharmony_ci * you may not use this file except in compliance with the License.
5fa7767c5Sopenharmony_ci * You may obtain a copy of the License at
6fa7767c5Sopenharmony_ci *
7fa7767c5Sopenharmony_ci *     http://www.apache.org/licenses/LICENSE-2.0
8fa7767c5Sopenharmony_ci *
9fa7767c5Sopenharmony_ci * Unless required by applicable law or agreed to in writing, software
10fa7767c5Sopenharmony_ci * distributed under the License is distributed on an "AS IS" BASIS,
11fa7767c5Sopenharmony_ci * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12fa7767c5Sopenharmony_ci * See the License for the specific language governing permissions and
13fa7767c5Sopenharmony_ci * limitations under the License.
14fa7767c5Sopenharmony_ci */
15fa7767c5Sopenharmony_ci
16fa7767c5Sopenharmony_ci#ifndef SCOPE_GUARD_H
17fa7767c5Sopenharmony_ci#define SCOPE_GUARD_H
18fa7767c5Sopenharmony_ci
19fa7767c5Sopenharmony_ci#include <functional>
20fa7767c5Sopenharmony_ci
21fa7767c5Sopenharmony_cinamespace OHOS {
22fa7767c5Sopenharmony_ci/*
23fa7767c5Sopenharmony_ci * The RAII feature is used to implement scope exit protection so that resources
24fa7767c5Sopenharmony_ci * can be released and the closure action can be performed in a unified manner when
25fa7767c5Sopenharmony_ci * the scope exits.
26fa7767c5Sopenharmony_ci */
27fa7767c5Sopenharmony_cinamespace Detail {
28fa7767c5Sopenharmony_citemplate <typename ExitAction>
29fa7767c5Sopenharmony_ciclass ScopeGuard {
30fa7767c5Sopenharmony_cipublic:
31fa7767c5Sopenharmony_ci    explicit ScopeGuard(ExitAction &&action) : action_(action), enable_(true) {}
32fa7767c5Sopenharmony_ci    ~ScopeGuard()
33fa7767c5Sopenharmony_ci    {
34fa7767c5Sopenharmony_ci        if (enable_) {
35fa7767c5Sopenharmony_ci            action_();
36fa7767c5Sopenharmony_ci        }
37fa7767c5Sopenharmony_ci    }
38fa7767c5Sopenharmony_ci
39fa7767c5Sopenharmony_ci    void Disable()
40fa7767c5Sopenharmony_ci    {
41fa7767c5Sopenharmony_ci        enable_ = false;
42fa7767c5Sopenharmony_ci    }
43fa7767c5Sopenharmony_ci
44fa7767c5Sopenharmony_ciprivate:
45fa7767c5Sopenharmony_ci    ExitAction action_;
46fa7767c5Sopenharmony_ci    bool enable_;
47fa7767c5Sopenharmony_ci};
48fa7767c5Sopenharmony_ci
49fa7767c5Sopenharmony_cistruct ScopeExitGuardHelper {};
50fa7767c5Sopenharmony_citemplate <typename ExitAction>
51fa7767c5Sopenharmony_cistatic inline ScopeGuard<ExitAction> operator+(ScopeExitGuardHelper, ExitAction &&action)
52fa7767c5Sopenharmony_ci{
53fa7767c5Sopenharmony_ci    return ScopeGuard<ExitAction>(std::forward<ExitAction>(action));
54fa7767c5Sopenharmony_ci}
55fa7767c5Sopenharmony_ci} // namespace Detail
56fa7767c5Sopenharmony_ci
57fa7767c5Sopenharmony_ci#define ON_SCOPE_EXIT(id) auto onScopeExitGuard##id = Detail::ScopeExitGuardHelper{} + [&]
58fa7767c5Sopenharmony_ci
59fa7767c5Sopenharmony_ci#define CANCEL_SCOPE_EXIT_GUARD(id) onScopeExitGuard##id.Disable()
60fa7767c5Sopenharmony_ci} // namespace OHOS
61fa7767c5Sopenharmony_ci#endif
62