rcpp_framework/core/containers/task_queue.h

// This file is originally from Trantor - TaskQueue.h

// Copyright (c) 2016-2021, Tao An.  All rights reserved.

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#pragma once

#include <functional>
#include <future>
#include <string>

/**
 * @brief This class is a pure virtual class that can be implemented as a
 * SerialTaskQueue or a ConcurrentTaskQueue.
 *
 */
class TaskQueue {
protected:
	TaskQueue(const TaskQueue &) = delete;
	TaskQueue &operator=(const TaskQueue &) = delete;
	// some uncopyable classes maybe support move constructor....
	TaskQueue(TaskQueue &&) noexcept(true) = default;
	TaskQueue &operator=(TaskQueue &&) noexcept(true) = default;

public:
	TaskQueue() {}
	virtual void runTaskInQueue(const std::function<void()> &task) = 0;
	virtual void runTaskInQueue(std::function<void()> &&task) = 0;
	virtual std::string getName() const {
		return "";
	};

	/**
	 * @brief Run a task in the queue sychronously. This means that the task is
	 * executed before the method returns.
	 *
	 * @param task
	 */
	void syncTaskInQueue(const std::function<void()> &task) {
		std::promise<int> prom;
		std::future<int> fut = prom.get_future();
		runTaskInQueue([&]() {
			task();
			prom.set_value(1);
		});
		fut.get();
	};
	virtual ~TaskQueue() {
	}
};