poll

poll.c

#define _GNU_SOURCE 1
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<string.h>
#include<assert.h>

#include<netinet/in.h>
#include<sys/socket.h>
#include<sys/types.h>
#include<arpa/inet.h>
#include<sys/select.h>
#include<poll.h>

#define MAX 1024

void Initfd(struct pollfd *fds)
{
    int i=0;
    for(;i<MAX;++i)
    {
        fds[i].fd=-1;
    }
}

void Insertfd(struct pollfd *fds,int fd,short events)
{
    int i=0;
    for(;i<MAX;++i)
    {
        if(fds[i].fd==-1)
        {
            fds[i].fd=fd;
            fds[i].events=events;
            break;
        }
    }
}

int main()
{
    int listenfd=socket(AF_INET,SOCK_STREAM,0);
    assert(listenfd!=-1);

    struct sockaddr_in ser,cli;
    ser.sin_family=AF_INET;
    ser.sin_port=htons(6000);
    ser.sin_addr.s_addr=inet_addr("127.0.0.1");

    int res=bind(listenfd,(struct sockaddr*)&ser,sizeof(ser));
    assert(res!=-1);

    listen(listenfd,5);

    struct  pollfd fds[MAX];
    Initfd(fds);
    fds[0].fd=listenfd;
    fds[0].events=POLLIN;//读事件
    while(1)
    {
        int n=poll(fds,MAX,-1);
        if(n==-1)
        {
            printf("poll error!\n");
            exit(0);
        }
        else if(n==0)
        {
            printf("time out\n");
            continue;
        }
        else
        {
            int i=0;
            for(;i<MAX;++i)
            {
                if(fds[i].revents & POLLRDHUP)
                {
                    printf("close\n");
                    close(fds[i].fd);
                    fds[i].fd=-1;
                    continue;
                }
                if(fds[i].revents & POLLIN)
                {
                    if(fds[i].fd==listenfd)
                    {
                        int len=sizeof(cli);
                        int c=accept(listenfd,(struct sockaddr*)&cli,&len);
                        if(c<=0)
                        {
                            printf("one error");
                            continue;
                        }
                        Insertfd(fds,c,POLLIN|POLLRDHUP);
                    }
                    else
                    {
                        char buff[128]={0};
                        int n=recv(fds[i].fd,buff,127,0);
                        if(n<=0)
                        {
                            printf("break\n");
                            close(fds[i].fd);
                            fds[i].fd=-1;
                            continue;
                        }
                        printf("%d:%s",fds[i].fd,buff);
                        send(fds[i].fd,"ok",2,0);

                    }
                }
            }
        }
    }

    return 0;
}