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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <utility> // for std::move, std::forward
namespace android {
namespace base {
// ScopeGuard ensures that the specified functor is executed no matter how the
// current scope exits.
template <typename F>
class ScopeGuard {
public:
constexpr ScopeGuard(F&& f) : f_(std::forward<F>(f)), active_(true) {}
constexpr ScopeGuard(ScopeGuard&& that) noexcept : f_(std::move(that.f_)), active_(that.active_) {
that.active_ = false;
}
template <typename Functor>
constexpr ScopeGuard(ScopeGuard<Functor>&& that) : f_(std::move(that.f_)), active_(that.active_) {
that.active_ = false;
}
~ScopeGuard() {
if (active_) f_();
}
ScopeGuard() = delete;
ScopeGuard(const ScopeGuard&) = delete;
void operator=(const ScopeGuard&) = delete;
void operator=(ScopeGuard&& that) = delete;
void Disable() { active_ = false; }
constexpr bool active() const { return active_; }
private:
template <typename Functor>
friend class ScopeGuard;
F f_;
bool active_;
};
template <typename F>
ScopeGuard<F> make_scope_guard(F&& f) {
return ScopeGuard<F>(std::forward<F>(f));
}
} // namespace base
} // namespace android
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