带有线程安全队列的C ++ 11事件循环(C++11 event loop with thread safe queue)

 我想创建一个事件循环类，它将在它自己的线程上运行，支持将任务添加为std::functions并执行它们。 为此，我从这里使用SafeQueue： https ：//stackoverflow.com/a/16075550/1069662 
 
class EventLoop
{
public:
typedef std::function<void()> Task;

EventLoop(){ stop=false; }

void add_task(Task t) { queue.enqueue(t); }

void start();

void stop() { stop = true; }

private:
    SafeQueue<Task> queue;
    bool stop;
};

void EventLoop::start()
{
    while (!stop) {
        Task t = queue.dequeue(); // Blocking call
        if (!stop) {
            t();
        }
    }    

    cout << "Exit Loop";
}
 
 然后，你会像这样使用它： 
 
EventLoop loop;
std::thread t(&EventLoop::start, &loop);

loop.add_task(myTask);
// do smth else

loop.stop();
t.join();
 
 我的问题是：如何优雅地停止线程？ 由于阻塞队列调用，此处不能退出循环。 

I want to create an event loop class that will run on it's own thread, support adding of tasks as std::functions and execute them. For this, I am using the SafeQueue from here: https://stackoverflow.com/a/16075550/1069662 
 
class EventLoop
{
public:
typedef std::function<void()> Task;

EventLoop(){ stop=false; }

void add_task(Task t) { queue.enqueue(t); }

void start();

void stop() { stop = true; }

private:
    SafeQueue<Task> queue;
    bool stop;
};

void EventLoop::start()
{
    while (!stop) {
        Task t = queue.dequeue(); // Blocking call
        if (!stop) {
            t();
        }
    }    

    cout << "Exit Loop";
}
 
Then, you would use it like this:
 
EventLoop loop;
std::thread t(&EventLoop::start, &loop);

loop.add_task(myTask);
// do smth else

loop.stop();
t.join();
 
My question is: how to stop gracefully the thread ? Here stop cannot exit the loop because of the blocking queue call.

原文：https://stackoverflow.com/questions/26441912