server.c

周立功Magic2410实验箱光盘源码 第5章Linux应用程序编写 5.1 HelloWorld程序实验 5.2 Linux定时器实验 5.3多进程实验 5.4多线程实验 5.5文件和目

/*
****************************************Copyright (c)**************************************************
**                               Guangzhou Zhiyuan Electronic Co.,LTD.
**                                     graduate school
**                                 http://www.zyinside.com
**
**------------------------------------- File Info ------------------------------------------------------
** File name:           server.c
** Last modified Date:  2005-12-30
** Last Version:        1.0
** Descriptions:        server of TCP.
**------------------------------------------------------------------------------------------------------
** Created by:          Ganda
** Created date:        2005-12-27
** Version:             1.0
** Descriptions:        Preliminary version.
**
**------------------------------------------------------------------------------------------------------
** Modified by:		Chenxibing
** Modified date:	2005-12-30	
** Version:		1.0.1
** Descriptions:	modified for MagicARM2410.
**
********************************************************************************************************
*/

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/wait.h>
#include <sys/socket.h>
                                  
#define PORT 5000                      // The port which is communicate with server
#define BACKLOG 10
#define LENGTH 512                     // Buffer length                                                                                 
int main ()
{   int sockfd;                        // Socket file descriptor
    int nsockfd;                       // New Socket file descriptor
    int num;
    int sin_size;                      // to store struct size
    char sdbuf[LENGTH];                // Send buffer
    struct sockaddr_in addr_local;     
    struct sockaddr_in addr_remote;    
    char sendstr[16]= {"123456789 abcde"};    
               
    /* Get the Socket file descriptor */  
    if( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1 )  
    {   
        printf ("ERROR: Failed to obtain Socket Despcritor.\n");
        return (0);
    }
    else
    {
        printf ("OK: Obtain Socket Despcritor sucessfully.\n");
    }
    
    /* Fill the local socket address struct */
    addr_local.sin_family = AF_INET;           // Protocol Family
    addr_local.sin_port = htons(PORT);         // Port number
    addr_local.sin_addr.s_addr  = INADDR_ANY;  // AutoFill local address
    bzero(&(addr_local.sin_zero), 8);          // Flush the rest of struct

    /*  Blind a special Port */
    if( bind(sockfd, (struct sockaddr*)&addr_local, sizeof(struct sockaddr)) == -1 )
    {  
    	  printf ("ERROR: Failed to bind Port %d.\n",PORT);
        return (0);
    }
    else
    {
        printf("OK: Bind the Port %d sucessfully.\n",PORT);
    }
   
    /*  Listen remote connect/calling */
    if(listen(sockfd,BACKLOG) == -1)    
    {  
        printf ("ERROR: Failed to listen Port %d.\n", PORT);
        return (0);
    }
    else
    {
        printf ("OK: Listening the Port %d sucessfully.\n", PORT);
    }
   
    while(1)
    {  
        sin_size = sizeof(struct sockaddr_in);  
        
        /*  Wait a connection, and obtain a new socket file despriptor for single connection */
        if ((nsockfd = accept(sockfd, (struct sockaddr *)&addr_remote, &sin_size)) == -1)
        {  
            printf ("ERROR: Obtain new Socket Despcritor error.\n");
            continue;
        }
        else
        {
            printf ("OK: Server has got connect from %s.\n", inet_ntoa(addr_remote.sin_addr)); 
        }
        
        /* Child process */
        if(!fork())                    
        {  
            printf("You can enter string, and press 'exit' to end the connect.\n");
            while(strcmp(sdbuf,"exit") != 0)
            { 
                scanf("%s", sdbuf); 
                if((num = send(nsockfd, sdbuf, strlen(sdbuf), 0)) == -1)
                {
                    printf("ERROR: Failed to sent string.\n");
                    close(nsockfd);
                    exit(1);
                }
                printf("OK: Sent %d bytes sucessful, please enter again.\n", num);  
            }
         }      
         close(nsockfd);  
         while(waitpid(-1, NULL, WNOHANG) > 0);    
     }    
}