C语言 LINUX 环境下 socket UDP 服务器客户端发送信息

来源：互联网发布：自学设计软件服装编辑：程序博客网时间：2024/05/17 22:39

服务器

#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>

#define MAXLINE 1024
#define SERV_PORT 8000

struct MSG_PACK
{
   char cmd;
   char status;
   short int len;
};

struct host
{
   char UserName[20];
   char Host[20];
   char IP[20];
   char PassWord [20];
   char SubNet[512];
   char Mode;
   char ConState;
   char Pin[20];
   char ConTrol;
   char RandPassword[10];
};

int main(void)
{
   int sockfd;
   struct sockaddr_in servaddr, cliaddr;

   sockfd = socket(AF_INET, SOCK_DGRAM, 0); /* create a socket */

   /* init servaddr */
   bzero(&servaddr, sizeof(servaddr));
   servaddr.sin_family = AF_INET;
   servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
   servaddr.sin_port = htons(SERV_PORT);

   /* bind address and port to socket */
   if(bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) == -1)
   {
        perror("bind error");
        exit(1);
   }

   do_echo(sockfd, (struct sockaddr *)&cliaddr, sizeof(cliaddr));

   close(sockfd);
   return 0;
}

void do_echo(int sockfd, struct sockaddr *pcliaddr, socklen_t clilen)
{

   int n;
   socklen_t len;
   char mesg[MAXLINE];

   for(;;)
   {
        len = clilen;

        /* waiting for receive data */
        n = recvfrom(sockfd, mesg, MAXLINE, 0, pcliaddr, &len);
        //mesg[n] ='/0';

        printf ("^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^n:%d   len=%d/n",n,len);
        struct MSG_PACK pocket;

        memcpy(&pocket,mesg,sizeof(struct MSG_PACK));

        printf("$$$$$$$$$$$$$$/n-----pocket1------->%d/n",pocket.cmd);

        printf("-----pocket2------->%d/n",pocket.status);

        printf("-----pocket3------->%d/n$$$$$$$$$$$$$$$/n",pocket.len);

        struct host sHost2 ;
        memcpy(&sHost2 , mesg + sizeof(struct MSG_PACK) , sizeof(struct host));
        printf("&&&&&&&&&&&&&&&&&&&&/n-----sHost1------->%s/n",sHost2.UserName);
        printf("-----sHost2------->%s/n",sHost2.Host);
        printf("-----sHost3------->%s/n",sHost2.IP);
        printf("-----sHost4------->%s/n",sHost2.PassWord);
        printf("-----sHost5------->%s/n",sHost2.SubNet);
        printf("-----sHost6------->%d/n",sHost2.Mode);
        printf("-----sHost7------->%d/n",sHost2.ConState);
        printf("-----sHost8------->%s/n",sHost2.Pin);
        printf("-----sHost9------->%d/n",sHost2.ConTrol);
        printf("-----sHost10------->%s/n&&&&&&&&&&&&&&&&&&&&/n",sHost2.RandPassword);

        /* sent data back to client */
        n = sendto(sockfd, mesg, n, 0, pcliaddr, len);

   }

}

客户端：

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <sys/socket.h>

#include <arpa/inet.h>

#include <unistd.h>

#define minornode 0 //从节点向主节点发送连接请求

#define hostnode_return 1 //主节点响应从节点的请求

#define minornode_change 2 //从节点向主节点发送更新请求

#define hostnode_returnchange 3 //主节点响应更新请求

//包头的定义

struct MSG_PACK

{

char cmd;

char status;

short int len;

};

//定义host

struct host

{

char UserName[20];

char Host[20];

char IP[20];

char PassWord [20];

char SubNet[512];

char Mode;

char ConState;

char Pin[20];

char ConTrol;

char RandPassword[10];

};

int main()

{

char sentbuf[1024];

struct host newhost;

memset(&newhost,0,sizeof(struct host));

strcpy(newhost.UserName,"aaaa");

strcpy(newhost.Host,"www");

strcpy(newhost.IP,"192.168.8.103");

strcpy(newhost.PassWord,"1111");

strcpy(newhost.SubNet,"255.255.255.0");

newhost.Mode=0;

newhost.ConState=1;

strcpy(newhost.Pin,"20");

newhost.ConTrol=0;

strcpy(newhost.RandPassword,"122122");

//printf("@@@@@@@@@@@@@@@@@@@@@@@@@@@@ %s %s %s %s %s %d %d %s %d %s @@@@@@@@@@@@@@@@@@@@@@@@@@@@ ",newhost.UserName,newhost.Host,newhost.IP,newhost.PassWord,newhost.SubNet,newhost.Mode,newhost.ConState,newhost.Pin,newhost.ConTrol,newhost.RandPassword);

struct MSG_PACK newpack;

newpack.cmd=1;

newpack.status=1;

newpack.len=sizeof(newhost);

//printf("@@@@@@@@@@@@@@@@@@@@@@@@@@@@ %d %d %d @@@@@@@@@@@@@@@@@@@@@@@@@@@ ",newpack.cmd,newpack.status,newpack.len);

memcpy(sentbuf,&newpack,sizeof(struct MSG_PACK));

memcpy(sentbuf+sizeof(struct MSG_PACK),&newhost,sizeof(struct host));

int iLen = sizeof(struct MSG_PACK)+ sizeof(struct host);

printf("-=-=-=-=-=-=-=-=-=-=-=-=%d ",iLen);

int sock;

//sendto中使用的对方地址

struct sockaddr_in servaddr;

//在recvfrom中使用的对方主机地址

struct sockaddr_in fromAddr;

unsigned int fromLen;

char recvBuffer[1024];

sock = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);

memset(&servaddr,0,sizeof(servaddr));

servaddr.sin_family=AF_INET;

servaddr.sin_addr.s_addr=inet_addr("192.168.8.200");

servaddr.sin_port = htons(8000);

if(sendto(sock,sentbuf,iLen,0,(struct sockaddr*)&servaddr,sizeof(servaddr)) != iLen)

{

perror("sendto error");

close(sock);

exit(1);

}

fromLen = sizeof(fromAddr);

if(recvfrom(sock,recvBuffer,1024,0,(struct sockaddr*)&fromAddr,&fromLen)<0)

{

perror("recvfrom error");

close(sock);

exit(1);

}

struct MSG_PACK pocket;

memcpy(&pocket , recvBuffer , sizeof(struct MSG_PACK));

printf("-----pocket1------->%d ",pocket.cmd);

printf("-----pocket2------->%d ",pocket.status);

printf("-----pocket3------->%d ",pocket.len);

struct host sHost2 ;

memcpy(&sHost2 , recvBuffer + sizeof(struct MSG_PACK) , sizeof(struct host));

printf("&&&&&&&&&&&&&&&&&&&& -----sHost1------->%s ",sHost2.UserName);

printf("-----sHost2------->%s ",sHost2.Host);

printf("-----sHost3------->%s ",sHost2.IP);

printf("-----sHost4------->%s ",sHost2.PassWord);

printf("-----sHost5------->%s ",sHost2.SubNet);

printf("-----sHost6------->%d ",sHost2.Mode);

printf("-----sHost7------->%d ",sHost2.ConState);

printf("-----sHost8------->%s ",sHost2.Pin);

printf("-----sHost9------->%d ",sHost2.ConTrol);

printf("-----sHost10------->%s &&&&&&&&&&&&&&&&&&&& ",sHost2.RandPassword);

close(sock);

return 0;

}