c语言udp自定义头文件 网络通信程序

//udp.h

#ifndef _UDP_H
#define _UDP_H
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>

typedef struct SockData
{
        struct sockaddr_in sockaddrIn;
        int sockFd;
        int sockaddrLen;
}SData;

void SetServerSockaddr(int port,struct SockData *sd);//初始化服务器端
void SetClientSockaddr(char ip[],int port,struct SockData *cd);//初始化客户端
int RecvMsg(struct SockData *sd,char msg[]);//接受消息 返回接受字节长度
int SendMsg(struct SockData *cd,char msg[]);//发送消息返回发送字节长度

#endif


//udp.c

 

#include "udp.h"

void SetServerSockaddr(int port,struct SockData *sd)
{
 int len;
 int sockfd;
 struct sockaddr_in ser;

 bzero(&ser, sizeof(ser));
 ser.sin_family = AF_INET;
 ser.sin_addr.s_addr =htonl(INADDR_ANY);
 ser.sin_port = htons(port);
 len = sizeof(ser);

 sockfd = socket(AF_INET, SOCK_DGRAM, 0);
 if(sockfd == -1)
 {
  perror("error!n");
  exit(-1);
 }

 bind(sockfd, (struct sockaddr *)&ser, sizeof(ser));
 sd->sockaddrIn=ser;
 sd->sockFd=sockfd;
 sd->sockaddrLen=len;
}
void SetClientSockaddr(char ip[],int port,struct SockData *cd)
{
 struct sockaddr_in cl;
 int sockfd;
 int len;
 sockfd = socket(AF_INET,SOCK_DGRAM,0);
 if(sockfd == -1)
 {
  perror("error!n");
  exit(-1);
 }
 int broadcast = 1;
 int num = 0;

 int ret_val = setsockopt(sockfd,SOL_SOCKET,SO_BROADCAST,&broadcast,sizeof(broadcast));
 if(ret_val == -1)
 {
  perror("Failed in setsockfd n");
  exit(-1);
 }

 cl.sin_family = AF_INET;
 cl.sin_port = htons(port);
 cl.sin_addr.s_addr = inet_addr(ip);

 len=sizeof(struct sockaddr_in);

 cd->sockaddrIn=cl;
 cd->sockFd=sockfd;
 cd->sockaddrLen=len;

 

}
int RecvMsg(struct SockData *sd,char msg[])
{
 int len;
 len=recvfrom(sd->sockFd,msg,1024,0,(struct sockaddr *)&(sd->sockaddrIn),&(sd->sockaddrLen));
 msg[len]='n';
 return len;

}
int SendMsg(struct SockData *cd,char msg[])
{
 int len;
 len= sendto(cd->sockFd,msg,strlen(msg),0,(struct sockaddr *)&(cd->sockaddrIn),cd->sockaddrLen);
 return len;
}


//client.c

 

#include "udp.h"
#include <stdio.h>
#include <string.h>

int main()
{
 int len;
 char recv_msg[256];
 char send_msg[256]="send come server !";
 SData cd;
 //SetServerSockaddr(8899,&cd);
 //SData cd;
 SetClientSockaddr("127.0.0.1",8899,&cd);
 int count=0;
 while(1)
 {
 count++;
  SendMsg(&cd,send_msg); 
  printf("send message : %sn", send_msg);//inet_ntoa(cl.sin_addr);

  bzero(&recv_msg,sizeof(recv_msg));
  RecvMsg(&cd,recv_msg);

  printf("recv message : %d%sn",count, recv_msg);//inet_ntoa(cl.sin_addr);

 }

 return 0;

}


//server.c

 

#include "udp.h"
#include <stdio.h>
#include <string.h>

int main()
{
 int len;
 char recv_msg[256];
 char send_msg[256]="send come server !";
 SData cd;
 SetServerSockaddr(8899,&cd);
 //SData cd;
 //SetClientSockaddr("127.0.0.1",8899,&cd);
 int count=0;
 while(1)
 {
  count++;

  bzero(&recv_msg,sizeof(recv_msg));
  RecvMsg(&cd,recv_msg);

  printf("recv message : %d%sn",count, recv_msg);//inet_ntoa(cl.sin_addr);


  SendMsg(&cd,send_msg); 
  printf("send message : %sn", send_msg);//inet_ntoa(cl.sin_addr);

   }

 return 0;

}