muli_server.c

嵌入式Linux程序设计与应用案例 电子书源码 中国电力出版社

/****************
//   name : multi_server.c
//   author : pyy
//   date : 2007-11-16
*******************/

#include<stdio.h>
#include<unistd.h>
#include<stdlib.h>
#include<errno.h>
#include<string.h>
#include<time.h>
#include<signal.h>
#include<sys/wait.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<netdb.h>

/* SIGCHLD 信息处理函数 */
static  void sigchld_handler()
{
    pid_t  PID;
    int  status;	
    /*清除 zombie进程*/
    while(PID = waitpid(-1,&status,WNOHANG)>0)
    printf("子进程 %d 结束.\n",PID);
    
    /*重新调用信息处理函数*/
    signal(SIGCHLD, sigchld_handler);	
	
}

int main()
{
    int  z, len_inet;	
    struct sockaddr_in adr_srvr,adr_clnt;
    int  sockfd, connfd;
    pid_t  PID;
    time_t  clock;
    struct tm*tm;
    int  len_time,i;
    char  buf[256];
    
    /*调用SIGCHLD信息处理函数*/	
    signal(SIGCHLD,sigchld_handler);
    
    memset(&adr_srvr, 0, sizeof(adr_srvr));
    if( argc == 2)
    adr_srvr.sin_addr.s_addr = inet_addr(argv[1]);
    else
    adr_srvr.sin_addr.s_addr = inet_addr("192.168.1.20");	
    
    adr_srvr.sin_family = AF_INET;
    adr_srvr.sin_port = htons(9090);
    
    /*建立 listening socket*/
    sockfd = socket(AF_INET, SOCK_STREAM, 0);	
    if (sockfd == -1) 
    {perror("socket error"); exit(1);}
    
    /*绑定 socket*/
    z = bind();
    if(z == -1)
    {perror("bind error"); exit(1);}
    
    /*监听 Client */
    z = listen(sockfd,10);
    if(z == -1)
    {perror("bind error"); exit(1);}
    
    while(1)
    {
        len_inet = sizeof(adr_clnt);
        /*接收Client 的连接 ，传回 connected socket*/	
    	connfd = accept(sockfd, (struct sockaddr *)&adr_clnt,&len_inet);
    	if(connfd == -1)
    	{ perror("connect error"); exit(1);}
    	
    	/*建立子进程*/
    	PID = fork();
    	if(PID > 0)
    	{
    	    /*父进程中 关闭connected socket*/
    	    close(connfd);
    	    /*监听while开头*/
    	    continue;
    	    	
    	}
    	printf("子进程处理........\n");
    	/*  在子进程中关闭 监听socket*/
    	close(sockfd);
    	for(i=0; i<10; i++)
    	{
    	     /*每隔1秒，传送现在时间，共传送10次*/	
    	    sleep(1);
    	    time(&clock);
    	    tm = gmtime(&clock);
    	    len_time = strftime(buf, 256," %A %T %D\n",tm);
    	    /* 将当前时间传给client*/
    	    if(write(connfd, buf, len_time)== -1) 
    	    {perror("write error"); exit(1);}
    	    	
    	}
    	/*将stop 字符串传给 Client*/
    sleep(1);
    sprintf(buf, "stop\n");
    write(connfd, buf, sizeof(buf));
    exit(0);
         	
    }
    
}