abstract_clock.h

#ifndef BEAST_CHRONO_ABSTRACT_CLOCK_H_INCLUDED
#define BEAST_CHRONO_ABSTRACT_CLOCK_H_INCLUDED
 
namespace beast {
 
template <class Clock>
class abstract_clock
{
public:
    using rep = typename Clock::rep;
    using period = typename Clock::period;
    using duration = typename Clock::duration;
    using time_point = typename Clock::time_point;
    using clock_type = Clock;
 
    static bool const is_steady = Clock::is_steady;
 
    virtual ~abstract_clock() = default;
    abstract_clock() = default;
    abstract_clock(abstract_clock const&) = default;
 
    [[nodiscard]] virtual time_point
    now() const = 0;
};
 
//------------------------------------------------------------------------------
 
namespace detail {
 
template <class Facade, class Clock>
struct abstract_clock_wrapper : public abstract_clock<Facade>
{
    explicit abstract_clock_wrapper() = default;
 
    using typename abstract_clock<Facade>::duration;
    using typename abstract_clock<Facade>::time_point;
 
    time_point
    now() const override
    {
        return Clock::now();
    }
};
 
}  // namespace detail
 
//------------------------------------------------------------------------------
 
template <class Facade, class Clock = Facade>
abstract_clock<Facade>&
get_abstract_clock()
{
    static detail::abstract_clock_wrapper<Facade, Clock> clock;
    return clock;
}
 
}  // namespace beast
 
#endif