1049e185fSopenharmony_ci/* 2049e185fSopenharmony_ci * Copyright (C) 2021 Huawei Device Co., Ltd. 3049e185fSopenharmony_ci * Licensed under the Apache License, Version 2.0 (the "License"); 4049e185fSopenharmony_ci * you may not use this file except in compliance with the License. 5049e185fSopenharmony_ci * You may obtain a copy of the License at 6049e185fSopenharmony_ci * 7049e185fSopenharmony_ci * http://www.apache.org/licenses/LICENSE-2.0 8049e185fSopenharmony_ci * 9049e185fSopenharmony_ci * Unless required by applicable law or agreed to in writing, software 10049e185fSopenharmony_ci * distributed under the License is distributed on an "AS IS" BASIS, 11049e185fSopenharmony_ci * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12049e185fSopenharmony_ci * See the License for the specific language governing permissions and 13049e185fSopenharmony_ci * limitations under the License. 14049e185fSopenharmony_ci */ 15049e185fSopenharmony_ci 16049e185fSopenharmony_ci#ifndef SCOPE_GUARD_H 17049e185fSopenharmony_ci#define SCOPE_GUARD_H 18049e185fSopenharmony_ci 19049e185fSopenharmony_ci#include <functional> 20049e185fSopenharmony_ci 21049e185fSopenharmony_cinamespace OHOS { 22049e185fSopenharmony_ci/* 23049e185fSopenharmony_ci * The RAII feature is used to implement scope exit protection so that resources 24049e185fSopenharmony_ci * can be released and the closure action can be performed in a unified manner when 25049e185fSopenharmony_ci * the scope exits. 26049e185fSopenharmony_ci */ 27049e185fSopenharmony_cinamespace Detail { 28049e185fSopenharmony_citemplate<typename ExitAction> 29049e185fSopenharmony_ciclass ScopeGuard { 30049e185fSopenharmony_cipublic: 31049e185fSopenharmony_ci explicit ScopeGuard(ExitAction &&action) : action_(action), enable_(true) {} 32049e185fSopenharmony_ci ~ScopeGuard() 33049e185fSopenharmony_ci { 34049e185fSopenharmony_ci if (enable_) { 35049e185fSopenharmony_ci action_(); 36049e185fSopenharmony_ci } 37049e185fSopenharmony_ci } 38049e185fSopenharmony_ci 39049e185fSopenharmony_ci void Disable() 40049e185fSopenharmony_ci { 41049e185fSopenharmony_ci enable_ = false; 42049e185fSopenharmony_ci } 43049e185fSopenharmony_ci 44049e185fSopenharmony_ciprivate: 45049e185fSopenharmony_ci ExitAction action_; 46049e185fSopenharmony_ci bool enable_; 47049e185fSopenharmony_ci}; 48049e185fSopenharmony_ci 49049e185fSopenharmony_cistruct ScopeExitGuardHelper {}; 50049e185fSopenharmony_citemplate<typename ExitAction> 51049e185fSopenharmony_cistatic inline ScopeGuard<ExitAction> operator+(ScopeExitGuardHelper, ExitAction &&action) 52049e185fSopenharmony_ci{ 53049e185fSopenharmony_ci return ScopeGuard<ExitAction>(std::forward<ExitAction>(action)); 54049e185fSopenharmony_ci} 55049e185fSopenharmony_ci} 56049e185fSopenharmony_ci 57049e185fSopenharmony_ci#define ON_SCOPE_EXIT(id) \ 58049e185fSopenharmony_ci auto onScopeExitGuard##id = Detail::ScopeExitGuardHelper{} + [ & ] 59049e185fSopenharmony_ci 60049e185fSopenharmony_ci#define CANCEL_SCOPE_EXIT_GUARD(id) \ 61049e185fSopenharmony_ci onScopeExitGuard##id.Disable() 62049e185fSopenharmony_ci} 63049e185fSopenharmony_ci#endif 64