1 /* 2 * Copyright (C) 2014 The Android Open Source Project 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 #ifndef ANDROID_BASE_SCOPEGUARD_H 18 #define ANDROID_BASE_SCOPEGUARD_H 19 20 #include <utility> // for std::move, std::forward 21 22 namespace android { 23 namespace base { 24 25 // ScopeGuard ensures that the specified functor is executed no matter how the 26 // current scope exits. 27 template <typename F> 28 class ScopeGuard { 29 public: 30 ScopeGuard(F&& f) : f_(std::forward<F>(f)), active_(true) {} 31 32 ScopeGuard(ScopeGuard&& that) : f_(std::move(that.f_)), active_(that.active_) { 33 that.active_ = false; 34 } 35 36 template <typename Functor> 37 ScopeGuard(ScopeGuard<Functor>&& that) : f_(std::move(that.f_)), active_(that.active_) { 38 that.active_ = false; 39 } 40 41 ~ScopeGuard() { 42 if (active_) f_(); 43 } 44 45 ScopeGuard() = delete; 46 ScopeGuard(const ScopeGuard&) = delete; 47 void operator=(const ScopeGuard&) = delete; 48 void operator=(ScopeGuard&& that) = delete; 49 50 void Disable() { active_ = false; } 51 52 bool active() const { return active_; } 53 54 private: 55 template <typename Functor> 56 friend class ScopeGuard; 57 58 F f_; 59 bool active_; 60 }; 61 62 template <typename F> 63 ScopeGuard<F> make_scope_guard(F&& f) { 64 return ScopeGuard<F>(std::forward<F>(f)); 65 } 66 67 } // namespace base 68 } // namespace android 69 70 #endif // ANDROID_BASE_SCOPEGUARD_H 71
