yolobs-studio/plugins/mac-avcapture/scope-guard.hpp

81 lines
1.5 KiB
C++
Raw Normal View History

2016-02-23 23:16:51 +00:00
/*
* Based on Loki::ScopeGuard
*/
#pragma once
#include <utility>
namespace scope_guard_util {
template <typename FunctionType>
class ScopeGuard {
public:
void dismiss() noexcept
{
dismissed_ = true;
}
explicit ScopeGuard(const FunctionType &fn)
: function_(fn)
{}
explicit ScopeGuard(FunctionType &&fn)
: function_(std::move(fn))
{}
ScopeGuard(ScopeGuard &&other)
: dismissed_(other.dismissed_),
function_(std::move(other.function_))
{
other.dismissed_ = true;
}
~ScopeGuard() noexcept
{
if (!dismissed_)
execute();
}
private:
void* operator new(size_t) = delete;
void execute() noexcept
{
function_();
}
bool dismissed_ = false;
FunctionType function_;
};
template <typename FunctionType>
ScopeGuard<typename std::decay<FunctionType>::type>
make_guard(FunctionType &&fn)
{
return ScopeGuard<typename std::decay<FunctionType>::type>{
std::forward<FunctionType>(fn)};
}
namespace detail {
enum class ScopeGuardOnExit {};
template <typename FunctionType>
ScopeGuard<typename std::decay<FunctionType>::type>
operator+(detail::ScopeGuardOnExit, FunctionType &&fn) {
return ScopeGuard<typename std::decay<FunctionType>::type>(
std::forward<FunctionType>(fn));
}
}
} // namespace scope_guard_util
#define SCOPE_EXIT_CONCAT2(x, y) x ## y
#define SCOPE_EXIT_CONCAT(x, y) SCOPE_EXIT_CONCAT2(x, y)
#define SCOPE_EXIT \
auto SCOPE_EXIT_CONCAT(SCOPE_EXIT_STATE, __LINE__) = \
::scope_guard_util::detail::ScopeGuardOnExit() + [&]() noexcept