自定义线程池

自定义线程池

注意： 需要c++17 或 c++20 的支持

代码实现:

#ifndef THREADPOOL_H
#define THREADPOOL_H

#include <vector>
#include <queue>
#include <thread>
#include <mutex>
#include <condition_variable>
#include <functional>
#include <future>
#include <atomic>
#include <iostream>

//线程池,单例类
class ThreadPool
{
   
public:
    static ThreadPool& getInstance()
    {
   
        //std::thread::hardware_concurrency() //获取线程数  最小10个线程
        static int size = std::max((int)std::thread::hardware_concurrency(),10);
        static ThreadPool instance(size,size * 2);
        return instance;
    }

    ThreadPool(ThreadPool const&) = delete;
    void operator=(ThreadPool const&) = delete;

    //增加运行的函数 动态获取类型
    template<typename F, typename... Args>
    auto enqueue(F&& f, Args&&... args) -> std::future<typename std::invoke_result<F,Args...>::type>
    {
   
        //返回类型
        using return_type = typename std::invoke_result<F,Args...>::type;
        //打包函数
        auto task = std::make_shared<std::packaged_task<return_type()> >(
            std::bind(std::forward<F>(f), std::forward<Args>(args)...)
            );

        std::future<return_type> res = task->get_future();
        {
   
            std::lock_guard <std::mutex> lock(m_queue_mutex);

            if (m_stop)
            {
   
                //return res;