epoll 封装

dwsocket.h

#pragma once

#include <string>
#include <sys/epoll.h>

namespace dw {

    using namespace std;

    class Addr
    {
    public:
        int port;
        string ip;
        Addr(string ip, int port);
        Addr();
        ~Addr();
        friend ostream& operator<<(ostream &out, const Addr &addr);
    private:

    };


    /*
     * 服务端Socket 完全异步
     */
    class ServerSocket
    {
    public:
        Addr *addr = NULL;
        int maxListenNum = 128;//最大监听数,libevent也是128
        int epollSize = 65535;//epoll 的最大监听数
        int maxEvents = 1024;
        int maxThread = 1; //最大线程数(socket开启时,会会根据cpu核心数,重新初始化该值)

        ServerSocket(int port);
        ~ServerSocket();
        int start();

    private:
        int socketfd = -1;
        int epollfd = -1;
        epoll_event* events;

        void initAddr(int port);
        int initSocket();
        int initEpoll();
        void setNonBlock(int fd); //设置非阻塞socket
        void initMaxThread();
        void loopWait();
        void addSocketFd(int fd);
        int initThreadPool(); //初始化线程池
    };

}

Addr.cpp

#include "dwsocket.h"

#include<iostream>

namespace dw {

    Addr::Addr() {
    }

    Addr::Addr(string ip, int port) {
        this->port = port;
        this->ip = ip;
    }

    Addr::~Addr() {
    }

    ostream& operator<<(ostream &out, const Addr &addr) {
        out << addr.ip << ":" << addr.port;
        return out;
    }


}

ServerSocket.cpp

#include "dwsocket.h"

#include<iostream>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <sys/sysinfo.h>

namespace dw {

    using namespace std;

    ServerSocket::ServerSocket(int port) {
        initAddr(port);
        initMaxThread();
    }

    ServerSocket::~ServerSocket() {
        delete addr;
        shutdown(socketfd, SHUT_RDWR);
    }

    void ServerSocket::initMaxThread() {
        int cpuCoreNum = get_nprocs();
        maxThread = cpuCoreNum * 2;
    }


    void ServerSocket::initAddr(int port) {
        addr = new Addr("127.0.0.1", port);
    }

    int ServerSocket::initSocket() {
        if (maxListenNum <= 0) {
            cout << "Error: maxListenNum 必须大于0 " << endl;
            return -1;
        }

        socketfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        if (socketfd < 0) {
            cout << "Error: socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)" << endl;
            return -1;
        }

        //设置socket
        setNonBlock(socketfd);
        int opt = 1;
        setsockopt(socketfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));

        struct sockaddr_in server_addr;
        server_addr.sin_family = AF_INET;
        server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
        server_addr.sin_port = htons(addr->port);

        int err = bind(socketfd, (struct sockaddr*) &server_addr, sizeof(server_addr));
        if (err < 0) {
            cout << "Error: bind(socketfd, (struct sockaddr*) &server_addr, sizeof(server_addr))" << endl;
            return -1;
        }

        err = listen(socketfd, maxListenNum);
        if (err < 0) {
            cout << "Error: listen(socketfd, maxListenNum)" << endl;
            return -1;
        }

        return 0;
    }

    void ServerSocket::setNonBlock(int fd) {
        int fl = fcntl(socketfd, F_GETFL);
        fcntl(socketfd, F_SETFL, fl | O_NONBLOCK);
    }

    int ServerSocket::initEpoll() {

        epollfd = epoll_create(epollSize);
        if (epollfd < 0) {
            cout << "Error: epoll_create(maxEvents)" << endl;
            return -1;
        }

        events = new epoll_event[maxEvents];
        addSocketFd(socketfd);

        return 0;
    }

    void ServerSocket::loopWait() {

        struct sockaddr_in clientaddr;
        socklen_t clilen = sizeof(clientaddr);

        while (1) {
            int num = epoll_wait(epollfd, events, maxEvents, -1); //返回活跃用户个数
            for (int i = 0; i < num; i++) {
                int connfd = -1;
                if (events[i].data.fd == socketfd) {
                    //新连接
                    cout << "新连接" << endl;
                    connfd = accept(socketfd, (struct sockaddr *) &clientaddr, &clilen);
                    if (connfd < 0) {
                        cout << "连接失败" << endl;
                        continue;
                    }
                    setNonBlock(connfd);
                }
                else if (events[i].events&EPOLLIN) {
                    //以前的连接,有数据读取
                    cout << "以前的连接 读取" << endl;
                    if ((connfd = events[i].data.fd) < 0) {
                        cout << "连接失败" << endl;
                        continue;
                    }
                }
                else if (events[i].events&EPOLLOUT) {
                    //以前的连接,有数据写出
                    cout << "以前的连接 写出" << endl;
                }
                else {
                    cout << "其他" << endl;
                    continue;
                }
                addSocketFd(connfd);
            }
        }
    }

    void ServerSocket::addSocketFd(int fd) {
        struct epoll_event event;
        event.data.fd = fd;
        event.events = EPOLLIN | EPOLLET;
        epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &event);
    }

    int ServerSocket::start() {
        int err = initSocket();
        if (err < 0) {
            cout << "Error: initSocket()" << endl;
            return -1;
        }

        err = initEpoll();
        if (err < 0) {
            cout << "Error: initEpoll()" << endl;
            return -1;
        }
        loopWait();
        return 0;
    }
}