/*
 * ThreadPool.cpp
 *
 *  Created on: 2015年11月24日
 */
#include "ThreadPool.h"
namespace gdface{
ThreadPool::ThreadPool(size_t concurrency)
    : concurrency(concurrency),stop(false)
{
    for(size_t i = 0;i<this->concurrency;++i)
        workers.emplace_back(
            [this]
            {
                for(;;)
                {
                    std::function<void()> task;

                    {
                        std::unique_lock<std::mutex> lock(this->queue_mutex);
                        this->condition.wait(lock,
                            [this]{ return this->stop || !this->tasks.empty(); });
                        if(this->stop && this->tasks.empty())
                            return;
                        task = std::move(this->tasks.front());
                        this->tasks.pop();
                    }

                    task();
                }
            }
        );
}

// the destructor joins all threads
ThreadPool::~ThreadPool()
{
    {
        std::unique_lock<std::mutex> lock(queue_mutex);
        stop = true;
    }
    condition.notify_all();
    for(std::thread &worker: workers)
        worker.join();
}

} /* namespace gdface */