jobsystem.hpp

#pragma once
#include <chrono>
#include <future>
#include <iostream>
#include <optional>
#include <queue>
#include <thread>
 
class JobSystem {
 public:
  JobSystem();
  ~JobSystem();
 
  void work();
 
  void set_stop(bool t);
 
  template <class Funct, typename... Args>
  auto addTask(Funct f, Args... a) -> std::future<decltype(f(a...))> {
    using ret = decltype(f(a...));
 
    std::function<ret()> fun = std::bind(f, a...);
 
    return setFuture(fun);
  }
 
 private:
  template <class Return>
  std::future<Return> setFuture(std::function<Return()> func) {
    std::shared_ptr<std::packaged_task<Return()>> task =
        std::make_shared<std::packaged_task<Return()>>(std::move(func));
 
    std::future<Return> future = task->get_future();
    add([task]() { (*task)(); });
    return future;
  }
 
  void add(std::function<void()> task);
 
  bool stop_;
  std::condition_variable condition_;
  std::mutex mutex_;
  std::vector<std::thread> workers_;
  std::queue<std::function<void()>> jobs_;
};