Atmosphere/stratosphere/libstratosphere/include/stratosphere/scope_guard.hpp
2018-10-31 05:04:00 +09:00

61 lines
1.8 KiB
C++

/*
* Copyright (c) 2018 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/* Scope guard logic lovingly taken from Andrei Alexandrescu's "Systemic Error Handling in C++" */
#pragma once
#include <utility>
template<class F>
class ScopeGuard {
private:
F f;
bool active;
public:
ScopeGuard(F f) : f(std::move(f)), active(true) { }
~ScopeGuard() { if (active) { f(); } }
void Cancel() { active = false; }
ScopeGuard() = delete;
ScopeGuard(const ScopeGuard &) = delete;
ScopeGuard& operator=(const ScopeGuard&) = delete;
ScopeGuard(ScopeGuard&& rhs) : f(std::move(rhs.f)), active(rhs.active) {
rhs.Cancel();
}
};
template<class F>
ScopeGuard<F> MakeScopeGuard(F f) {
return ScopeGuard<F>(std::move(f));
}
enum class ScopeGuardOnExit {};
template <typename F>
ScopeGuard<F> operator+(ScopeGuardOnExit, F&& f) {
return ScopeGuard<F>(std::forward<F>(f));
}
#define CONCATENATE_IMPL(S1, s2) s1##s2
#define CONCATENATE(s1, s2) CONCATENATE_IMPL(s1, s2)
#ifdef __COUNTER__
#define ANONYMOUS_VARIABLE(pref) CONCATENATE(pref, __COUNTER__)
#else
#define ANONYMOUS_VARIABLE(pref) CONCATENATE(pref, __LINE__)
#endif
#define ON_SCOPE_EXIT auto ANONYMOUS_VARIABLE(SCOPE_EXIT_STATE_) = ScopeGuardOnExit() + [&]()