网络编程 day4

?IO多路复用服务器

?

#include <stdio.h>
#include "/home/ubuntu/head.h"

#define IP "192.168.124.85"
#define PORT 8888

int deal_cli_msg(int i,struct sockaddr_in cin,fd_set *preadfds,int *pmaxfd);
int deal_cli_connect(int sfd,struct sockaddr_in *pcin,fd_set *preadfds,int *pmaxfd);

int main(int argc, const char *argv[])
{
    //创建流式套接字
    int sfd=socket(AF_INET,SOCK_STREAM,0);
    if(sfd<0)
    {
        ERR_MSG("socket");
        return -1;
    }
    printf("socket create success sfd=%d __%d__\n",sfd,__LINE__);

    //允许端口快速被复用---监测端口号是否真的有进程在占用，如果没有，则快速复用
    int reuse = 1;
    if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0)
    {
        ERR_MSG("setsockopt");
        return -1;
    }
    printf("允许端口快速复用成功\n");

    //定义并填充地址信息结构体，给服务绑定使用
    //真实的地址信息结构体根据地址族指定
    struct sockaddr_in sin;
    sin.sin_family   = AF_INET;
    sin.sin_port     = htons(PORT);
    sin.sin_addr.s_addr =inet_addr(IP);

    //绑定服务器自身的地址信息
    if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin))<0)
    {
        ERR_MSG("bind");
        return -1;
    }
    printf("bind success __%d__\n",__LINE__);
    //讲套接字设置为被动接听状态
    if(listen(sfd,128)<0)
    {
        ERR_MSG("listen");
        return -1;
    }
    printf("listen success __%d__\n",__LINE__);

    //创建一个读集合
    //fd_set本质上是一个结构体，内部仅有一个long类型数组成员
    //readfds初始化
    fd_set readfds, tempfds;
    FD_ZERO(&readfds);

    //将需要监测的文件描述符填充到读集合中
    FD_SET(0,&readfds);
    FD_SET(sfd,&readfds);

    int maxfd= sfd;
    int newfd;
    int s_res = 0;                                                                                                                           
    struct sockaddr_in cin;
    socklen_t addrlen = sizeof(cin);
    char buf[128] = "";
    ssize_t res = 0;
    while(1)
    {
        tempfds = readfds;
        //调用select IO多路复用函数
        s_res = select(maxfd+1,&tempfds,NULL,NULL,NULL);
        if(s_res < 0)
        {
            ERR_MSG("select");
            return -1;
        }
        else if(0 == s_res)
        {
            printf("time out ...\n");
            break;
        }

        //判断哪个文件描述符准备就绪
        for(int i= 0;i<=maxfd;i++)
        {
            if(FD_ISSET(i,&tempfds)==0)
            {
                continue;
            }
            if(0==i)
            {
                printf("触发键盘输入事件");
                fgets(buf,sizeof(buf),stdin);
                buf[strlen(buf)-1]='\0';
                printf("buf=%s\n",buf);


            }
            else if(i == sfd)
            {

                printf("触发客户端连接事件\n");
                deal_cli_connect(sfd,&cin,&readfds,&maxfd);
            }
            //接收客户端数据
            else
            {

                printf("触发客户端交互事件\n");
                deal_cli_msg(i,cin,&readfds,&maxfd);
            }
        }

    }
    //关闭所有文件描述符
    close(newfd);
    if(close(sfd)<0)
    {
        ERR_MSG("close");
        return -1;
    }
    return 0;
}

int deal_cli_msg(int i,struct sockaddr_in cin,fd_set *preadfds,int *pmaxfd)
{
    char buf[128]="";
    bzero(buf,sizeof(buf));

    ssize_t res = recv(i,buf,sizeof(buf),0);
    if(res<0)
    {
        ERR_MSG("recv");
        return -1;
    }
    else if(0 == res)
     {
         printf("[%s ; %d] newfd= %d 客服端下线　__%d__ \n",\
                 inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),i,__LINE__);
         close(i);
         FD_CLR(i,preadfds);
         while(FD_ISSET(*pmaxfd,preadfds)==0 && (*pmaxfd)-->0);
         return 0;
     }
     printf("[%s ; %d] newfd= %d : %s __%d__ \n",\
             inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),i,buf,__LINE__);
     //向客户端发送数据
     strcat(buf,"^_^");
     if(send(i,buf,sizeof(buf),0)<0)
     {
         ERR_MSG("send");
         return -1;                                                                     
     }
     printf("send success __%d__\n",__LINE__);
     return 0;
 }
 
 int deal_cli_connect(int sfd,struct sockaddr_in *pcin,fd_set *preadfds,int *pmaxfd)
 {
     socklen_t addrlen = sizeof(*pcin);
     int newfd = accept(sfd,(struct sockaddr*)pcin,&addrlen);
     if(newfd<0)
     {
         ERR_MSG("accept");
         return -1;
     }
 
     printf("[%s ; %d] newfd=%d 客服端连接成功　__%d__ \n",\
             inet_ntoa(pcin->sin_addr),ntohs(pcin->sin_port),newfd,__LINE__);
     FD_SET(newfd,preadfds);
     *pmaxfd = *pmaxfd>newfd ?*pmaxfd:newfd;
 
     return 0;
 }
                                                                                        

IO多路复用客户端

 #include <stdio.h>
 #include "/home/ubuntu/head.h"
 
 #define IP "192.168.10.1"
 #define PORT 8888
 int main(int argc, const char *argv[])
 {
     //创建流式套接字
     int cfd=socket(AF_INET,SOCK_STREAM,0);
     if(cfd<0)
     {
         ERR_MSG("socket");
         return -1;
     }
     printf("socket create success sfd=%d __%d__\n",cfd,__LINE__);
 
     //填充服务器的地址信息，给connect函数去连接
     struct sockaddr_in sin;
     sin.sin_family   = AF_INET;
     sin.sin_port     = htons(PORT);
     sin.sin_addr.s_addr =inet_addr(IP);
 
 
     if(connect(cfd,(struct sockaddr*)&sin,sizeof(sin))<0)
     {
         ERR_MSG("connect");
         return -1;
     }
     printf("bind success __%d__\n",__LINE__);
 
 
     //创建一个写集合
     fd_set writecfd;
     FD_ZERO(&writecfd);
 
     //将需要监测的文件描述符填充到写集合
     FD_SET(0,&writecfd);
     FD_SET(cfd,&writecfd);
 
 
     int s_res=0;
     char buf[128] = "";
     ssize_t res = 0;
     while(1)
     {
         //调用select函数
         s_res = select(cfd+1,&writecfd,NULL,NULL,NULL);
         if(s_res<0)
         {
             ERR_MSG("select");
             return -1;
         }
         else if(0 == s_res)
         {
             printf("time out ...\n");
             break;
         }
 
         if(FD_ISSET(0,&writecfd))
         {
             bzero(buf,sizeof(buf));
             //向服务器发送数据
             printf("请输入>>> "); 
             fgets(buf,sizeof(buf),stdin);
             buf[strlen(buf)-1] = '\0';
 
             if(send(cfd,buf,sizeof(buf),0)<0)
             {
                 ERR_MSG("send");
                 return -1;
             }
             printf("send success __%d__\n", __LINE__);
 
 
         }
 
 
         if(FD_ISSET(cfd,&writecfd))
         {
             //客服端
             bzero(buf,sizeof(buf));
             res = recv(cfd,buf,sizeof(buf),0);
             if(res<0)
             {
                 ERR_MSG("recv");
                 return -1;
             }
             else if(0 == res)
             {
                 printf("[%s : %d]服务器下线　__%d__\n",\
                         inet_ntoa(sin.sin_addr),ntohs(sin.sin_port),__LINE__);
                 close(cfd);
                 break;
             }
             printf("[%s : %d] %s　__%d__\n",\
                     inet_ntoa(sin.sin_addr),ntohs(sin.sin_port),buf,__LINE__);
         }
     }
 
 
     //关闭所有文件描述符
     if(close(cfd)<0)
     {
         ERR_MSG("close");
         return -1;
     }
     return 0;
 }