EventLoopThreadPool.h

#pragma once

#include "noncopyable.h"

#include <functional>
#include <memory>
#include <string>
#include <vector>

class EventLoop;
class EventLoopThread;

class EventLoopThreadPool {
  public:
    using ThreadInitCallback = std::function<void(EventLoop *)>;

    EventLoopThreadPool(EventLoop *baseLoop, const std::string &nameArg);
    ~EventLoopThreadPool();

    void setThreadNum(int numThreads) { numThreads_ = numThreads; } // 设置线程池线程数量

    void start(const ThreadInitCallback &cb = ThreadInitCallback());

    // 如果工作在多线程中，baseLoop_ 默认以轮询的方式分配 channel 给 subloop
    EventLoop *getNextLoop();

    std::vector<EventLoop *> getAllLoops();

    bool started() const { return started_; }
    const std::string name() const { return name_; }

  private:
    EventLoop *baseLoop_;
    std::string name_;
    bool started_;
    int numThreads_;
    int next_; // 轮询下标
    std::vector<std::unique_ptr<EventLoopThread>> threads_;
    std::vector<EventLoop *> loops_;
};