c++线程池

#include <iostream>
#include <thread>
#include <mutex>
#include <string>
#include <condition_variable>
#include <queue>
#include <vector>
#include <functional>



class ThreadPool
{
public:
	ThreadPool(int numThreads) : stop(false)
	{
		for (int i = 0; i < numThreads; i++)
		{
			threads.emplace_back
			(
				[this]()
				{
					while (1)
					{
						std::unique_lock<std::mutex> lock(mux);
						condition.wait
							(lock, 
								[this]()
								{
									return !tasks.empty() || stop;
								}
							);

						if (stop && tasks.empty()) { return; }

						std::function<void()> task(std::move(tasks.front()));

						tasks.pop();
						lock.unlock();
						task();
					}
				}
			);
		}
	}

	~ThreadPool()
	{
		{	//指定锁的范围
			std::unique_lock<std::mutex> lock(mux);
			stop = true;
		}
		condition.notify_all();

		for (auto& t : threads)
		{
			t.join();
		}
	}
	template<class F, class... Args>
	void enqueue(F &&f, Args&&... args)
	{
		std::function<void()> task = std::bind(std::forward<F>(f), std::forward<Args>(args)...);
		
		{	//指定锁的范围
			std::unique_lock<std::mutex> lock(mux);
			tasks.emplace(std::move(task));
		}
		condition.notify_one();
	}


private:
	std::vector<std::thread> threads;
	std::queue<std::function<void()>> tasks;

	std::mutex mux;
	std::condition_variable condition;

	bool stop;
};



int main()
{
	ThreadPool pool(4);
	for (int i = 0; i < 10; i++)
	{
		pool.enqueue
		(
			[i]()
			{
				std::cout << "task:" << i << std::endl;
				std::this_thread::sleep_for(std::chrono::seconds(1));
			}
		);


	}
}