epoll
#include <sys/socket.h>
#include <sys/epoll.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <iostream>
using namespace std;
/*
typedef union epoll_data
{
void *ptr;
int fd;
__uint32_t u32;
__uint64_t u64;
} epoll_data_t;
struct epoll_event
{
__uint32_t events; // Epoll events /
epoll_data_t data; // User data variable /
};
*/
#define MAX_EVENTS 10
struct epoll_event ev, clientevents[MAX_EVENTS],events[MAX_EVENTS+1];
int listenfd, connfd, nfds, epollfd;
void setnonblocking(int sock)
{
int opts;
opts=fcntl(sock,F_GETFL);
if(opts<0)
{
perror("fcntl(sock,GETFL)");
//exit(0);
}
opts = opts|O_NONBLOCK;
if(fcntl(sock,F_SETFL,opts)<0)
{
perror("fcntl(sock,SETFL,opts)");
// exit(1);
}
}
//初始化event，data.u32为0表示未使用
void InitEvents()
{
int i;
for(i=0;i<MAX_EVENTS;i++)
{
clientevents[i].data.u32=0;
}
}
//获取未被使用的clientevents序号
int GetEmptyEventsId()
{
int i;
for(i=0;i<MAX_EVENTS;i++)
{
if(clientevents[i].data.u32==0)
return i;
}
return -1;
}
//对断开的套接字清理
void DelEventsFd(int fd)
{
int i;
for(i=0;i<MAX_EVENTS;i++)
{
if(clientevents[i].data.fd==fd)
{
epoll_ctl(epollfd,EPOLL_CTL_DEL,fd,&clientevents[i]);
clientevents[i].data.u32=0;
close(fd);
}
break;
}
}
int main()
{
//////////创建listen////////////////////
short port = 8888;
listenfd=socket(AF_INET,SOCK_STREAM,0);
setnonblocking(listenfd);
sockaddr_in sin;
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
sin.sin_port = htons(port);
bind(listenfd, (struct sockaddr*)&sin, sizeof(sin));
listen(listenfd, 5);
//////////////创建epoll///
InitEvents();
epollfd=epoll_create(MAX_EVENTS);
if(epollfd<=0)
{
printf("create errr\n");
return 0;
}else
{ printf("EpollFd:%d\n",epollfd);
}
//////////////////设置属性加入信号///////////////
ev.events=EPOLLIN;
ev.data.fd=listenfd;
if(epoll_ctl(epollfd,EPOLL_CTL_ADD,listenfd,&ev)==0)
printf("Set nfds OK\n");
int i;
/////////////////////////////////////
while(true)
{
nfds=epoll_wait(epollfd,events,MAX_EVENTS,-1);
if(nfds>0)
printf("nfds:%d\n",nfds);
for(i=0;i<nfds;i++)
{
if(events[i].data.fd==listenfd){
sockaddr_in local;
socklen_t addrlen=sizeof(local);
connfd=accept(listenfd,(struct sockaddr*)&local,&addrlen);
printf("New Link Fd:%d\n",connfd);
int id=GetEmptyEventsId();
if(id==-1)
{
printf("Not Empty\n");
continue;
}
clientevents[id].data.u32=1;
setnonblocking(connfd);
clientevents[id].data.fd=connfd;
clientevents[id].events=EPOLLIN|EPOLLET;
if(epoll_ctl(epollfd,EPOLL_CTL_ADD,connfd,&clientevents[id])==0)
printf("Set OK linkfd:%d eventid:%d\n",connfd,id);
}else
{
char temp[256]={0};
int n=recv(events[i].data.fd,temp,256,0);
printf("Message from:%d len:%d data:%s\n",events[i].data.fd,n,temp);
if(n<=0)
{
printf("fd:%d closed\n",events[i].data.fd);
DelEventsFd(events[i].data.fd);
}
}
}
}
//////////关闭///////////////////
close(epollfd);
return 0;
}