Sprout/testspr/singleton.hpp
2018-12-30 17:25:21 +09:00

90 lines
2.5 KiB
C++

/*=============================================================================
Copyright (c) 2011-2018 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#ifndef TESTSPR_SINGLETON_HPP
#define TESTSPR_SINGLETON_HPP
#include <sprout/config.hpp>
#include <sprout/utility/noncopyable.hpp>
#include <sprout/assert.hpp>
namespace testspr {
//
// singleton_module
//
class singleton_module
: public sprout::noncopyable
{
private:
static inline SPROUT_NON_CONSTEXPR bool& get_lock() {
static bool lock = false;
return lock;
}
public:
static inline SPROUT_NON_CONSTEXPR void lock() {
get_lock() = true;
}
static inline SPROUT_NON_CONSTEXPR void unlock() {
get_lock() = false;
}
static inline SPROUT_NON_CONSTEXPR bool is_locked() {
return get_lock();
}
};
namespace detail {
template<typename T>
class singleton_wrapper
: public T
{
public:
static bool m_is_destroyed;
public:
~singleton_wrapper() {
m_is_destroyed = true;
}
};
template<typename T>
bool testspr::detail::singleton_wrapper<T>::m_is_destroyed = false;
} // namespace detail
//
// singleton
//
template<typename T>
class singleton
: public testspr::singleton_module
{
public:
typedef T instance_type;
private:
static instance_type& instance;
private:
static inline SPROUT_NON_CONSTEXPR void use(const instance_type&) {}
static inline SPROUT_NON_CONSTEXPR instance_type& get_instance() {
static detail::singleton_wrapper<instance_type> t;
SPROUT_ASSERT(!testspr::detail::singleton_wrapper<instance_type>::m_is_destroyed);
use(instance);
return static_cast<instance_type&>(t);
}
public:
static inline SPROUT_NON_CONSTEXPR instance_type& get_mutable_instance() {
SPROUT_ASSERT(!is_locked());
return get_instance();
}
static inline SPROUT_NON_CONSTEXPR instance_type const& get_const_instance() {
return get_instance();
}
static inline SPROUT_NON_CONSTEXPR bool is_destroyed() {
return testspr::detail::singleton_wrapper<instance_type>::m_is_destroyed;
}
};
template<typename T>
T& singleton<T>::instance = testspr::singleton<T>::get_instance();
} // namespace testspr
#endif // #ifndef TESTSPR_SINGLETON_HPP