libevent实现TCP 服务端

libevent实现Tcp Server基于bufferevent实现

/********************************************************
Copyright (C),  2016-2018,
FileName:		main
Author:        	woniu201
Email:         	wangpengfei.201@163.com
Created:       	2018/11/21
Description:    使用libevent实现TCP Server
********************************************************/
#include <iostream>
#include <string.h>
#include <event2/event.h>
#include <event2/bufferevent.h>
#include <event2/listener.h>

#ifdef _WIN32
#include <windows.h>
#include <time.h>
#include <ws2tcpip.h>
#else
#include <unistd.h>
#include <arpa/inet.h>
#endif

#pragma comment(lib, "ws2_32.lib")
#pragma comment(lib, "wsock32.lib")
#pragma comment(lib, "libevent.lib")
#pragma comment(lib, "libevent_core.lib")
#pragma comment(lib, "libevent_extras.lib")

using namespace std;

/************************************
@ Brief:		读缓冲区回调
@ Author:		woniu201 
@ Created:		2018/11/21
@ Return:            
************************************/
void read_cb(struct bufferevent *bev, void *arg)
{
	char buf[1024] = {0};
	char* ip = (char*)arg;

	bufferevent_read(bev, buf, sizeof(buf));
	
	cout << "client " << ip << " say:" << buf << endl;
    

	//写数据给客户端
	const char *p = "i am server, i received your msg!" ;
	bufferevent_write(bev, p, strlen(p)+1);
}


/************************************
@ Brief:		写缓冲区回调
@ Author:		woniu201 
@ Created:		2018/11/21
@ Return:            
************************************/
void write_cb(struct bufferevent *bev, void *arg)
{
	cout << "I'm 服务器，成功写数据给客户端，写缓冲回调函数被调用..." << endl;
}

/************************************
@ Brief:		事件回调
@ Author:		woniu201 
@ Created:		2018/11/21
@ Return:            
************************************/
void event_cb(struct bufferevent *bev, short events, void *arg)
{
	char* ip = (char*)arg;
	if (events & BEV_EVENT_EOF)
	{
		cout << "connection closed:" << ip << endl;
	}
	else if (events & BEV_EVENT_ERROR)
	{
		cout << "some other error !" << endl;
	}

	bufferevent_free(bev);
	cout << "bufferevent 资源已经被释放..." << endl;
}

/************************************
@ Brief:		监听回调
@ Author:		woniu201 
@ Created:		2018/11/21
@ Return:            
************************************/
void cb_listener(struct evconnlistener *listener, evutil_socket_t fd, struct sockaddr *addr, int len, void *ptr)
{
	struct sockaddr_in* client = (sockaddr_in*)addr ;
	cout << "connect new client: " << inet_ntoa(client->sin_addr) << "::"<< ntohs(client->sin_port)<< endl;

	struct event_base *base = (struct event_base*)ptr;

	//添加新事件
	struct bufferevent *bev;
	bev = bufferevent_socket_new(base, fd, BEV_OPT_CLOSE_ON_FREE);
	
	//给bufferevent缓冲区设置回调
	bufferevent_setcb(bev, read_cb, write_cb, event_cb, inet_ntoa(client->sin_addr));

	//启动 bufferevent的 读缓冲区。默认是disable 的
	bufferevent_enable(bev, EV_READ);
}

int main()
{
#ifdef WIN32
	WORD wVersionRequested;
	WSADATA wsaData;
	wVersionRequested = MAKEWORD(2, 2);
	(void)WSAStartup(wVersionRequested, &wsaData);
#endif
	//init server
	struct sockaddr_in serv;

	memset(&serv, 0, sizeof(serv));
	serv.sin_family = AF_INET;
	serv.sin_port = htons(8888);
	serv.sin_addr.s_addr = htonl(INADDR_ANY);

	//创建 event_base
	struct event_base * base;
	base = event_base_new();

	//创建套接字
	//绑定
	//接收连接请求
	struct evconnlistener* listener;
	listener = evconnlistener_new_bind(base, cb_listener, base, LEV_OPT_CLOSE_ON_FREE|LEV_OPT_REUSEABLE, 36, (struct  sockaddr*)&serv, sizeof(serv));

	//启动循环监听
	event_base_dispatch(base);
	evconnlistener_free(listener);
	event_base_free(base);
	return 0;
}