run_loop.h

/*
**  UICore
**  Copyright (c) 1997-2015 The UICore Team
**
**  This software is provided 'as-is', without any express or implied
**  warranty.  In no event will the authors be held liable for any damages
**  arising from the use of this software.
**
**  Permission is granted to anyone to use this software for any purpose,
**  including commercial applications, and to alter it and redistribute it
**  freely, subject to the following restrictions:
**
**  1. The origin of this software must not be misrepresented; you must not
**     claim that you wrote the original software. If you use this software
**     in a product, an acknowledgment in the product documentation would be
**     appreciated but is not required.
**  2. Altered source versions must be plainly marked as such, and must not be
**     misrepresented as being the original software.
**  3. This notice may not be removed or altered from any source distribution.
**
**  Note: Some of the libraries UICore may link to may have additional
**  requirements or restrictions.
**
**  File Author(s):
**
**    Magnus Norddahl
*/

#pragma once

#include <functional>
#include <future>

namespace uicore
{
    class RunLoop
    {
    public:
        static void run();
        
        static void exit();
        
        static bool process(int timeout_ms = 0);
        
        static void main_thread_async(std::function<void()> func);
        
        template<typename T>
        static std::future<T> main_thread_task(std::function<T()> func)
        {
            auto promise = std::make_shared<std::promise<T>>();
            main_thread_async([=]()
            {
                try
                {
                    promise->set_value(func());
                }
                catch (...)
                {
                    promise->set_exception(std::current_exception());
                }
            });
            return promise->get_future();
        }

        static std::future<void> main_thread_task(std::function<void()> func)
        {
            auto promise = std::make_shared<std::promise<void>>();
            main_thread_async([=]()
            {
                try
                {
                    func();
                    promise->set_value();
                }
                catch (...)
                {
                    promise->set_exception(std::current_exception());
                }
            });
            return promise->get_future();
        }
    };
}