udp多线程服务器demo

//服务器代码

#include <sys/socket.h>
#include<sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#include<string.h>
#include<stdio.h>
#include<stdlib.h>
#include<errno.h>

#define ERR_EXIT(m)\
{\
	perror(m);\
	exit(1);\
}\

static in_port_t port=2525;
void str_echo(int sockfd,struct sockaddr_in cliaddr)
{
	printf("str_echo works\n");
	ssize_t n;
	socklen_t len=sizeof(cliaddr);
	char buf[1024]="i am here";
	n=sendto(sockfd,buf,strlen(buf),0,(struct sockaddr*)&cliaddr,sizeof(cliaddr));
	if(n==-1)
		ERR_EXIT("sendto");
	printf("send to client\n");
	memset(buf,0,sizeof(buf));
	while(1)
	{
		n=recvfrom(sockfd,buf,1024,0,(struct sockaddr*)&cliaddr,&len);
		sendto(sockfd,buf,1024,0,(struct sockaddr*)&cliaddr,sizeof(cliaddr));
		memset(buf,0,sizeof(buf));
	}
}

static void* doit(void*);

int main()
{
	int listenfd;
	pthread_t tid;
	socklen_t len;
	struct sockaddr_in cliaddr,servaddr,*tmp;
	//int on=1;
	listenfd=socket(AF_INET,SOCK_DGRAM,0);
	if(listenfd==-1)
		ERR_EXIT("socket");
	memset(&servaddr,0,sizeof(servaddr));
	servaddr.sin_family=AF_INET;
	servaddr.sin_port=2525;
	servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
//	setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(int));
	bind(listenfd,(struct sockaddr*)&servaddr,sizeof(servaddr));
//	listen(listenfd,SOMAXCONN);
	int n;
	while(1)
	{
		char mesg[1024]={0};
		len=sizeof(servaddr);
		tmp=malloc(sizeof(struct sockaddr_in));
	//	*iptr=accept(listenfd,(struct sockaddr*)&cliaddr,&len);
		n=recvfrom(listenfd,mesg,1024,0,(struct sockaddr*)&cliaddr,&len);
		if(n==-1)
			ERR_EXIT("recvfrom");
		printf("get conn\n");
		printf("%s\n",mesg);
//		fputs(mesg,stdout);
		*tmp=cliaddr;
		pthread_create(&tid,NULL,&doit,tmp);
		memset(mesg,0,sizeof(mesg));
	}
}

static void* doit(void *arg)
{
	printf("a thread created\n");
	struct sockaddr_in cliaddr=*((struct sockaddr_in*)arg);
	free(arg);
	int connfd;
	connfd=socket(AF_INET,SOCK_DGRAM,0);
	struct sockaddr_in servaddr;
	memset(&servaddr,0,sizeof(servaddr));
	servaddr.sin_family=AF_INET;
	servaddr.sin_port=++port;
	servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
	bind(connfd,(struct sockaddr*)&servaddr,sizeof(servaddr));
	pthread_detach(pthread_self());
	str_echo(connfd,cliaddr);
	close(connfd);
	return (NULL);
}

//客户端代码

#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include<stdio.h>
#include<stdlib.h>
#include <errno.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include<pthread.h>
#include<string.h>
#include<unistd.h>
#define ERR_EXIT(m)\
{\
        perror(m);\
        exit(1); \
}\

void* copyto(void*);
static int sockfd;
static FILE* fp;
static struct sockaddr serv;
void str_cli(FILE* fp_arg,int sock_arg,struct sockaddr* servaddr,socklen_t servlen)
{
        char recvline[1024]="hello";
        pthread_t tid;
        sockfd=sock_arg;
        fp=fp_arg;
        socklen_t len=sizeof(struct sockaddr_in);
        sendto(sockfd,recvline,strlen(recvline),0,servaddr,sizeof(struct sockaddr));
	memset(recvline,0,sizeof(recvline));
        recvfrom(sockfd,recvline,1024,0,&serv,&len);
	fputs(recvline,stdout);
	printf("\n");
        //serv=servaddr;
        pthread_create(&tid,NULL,copyto,&serv);
        memset(recvline,0,sizeof(recvline));
        while(recvfrom(sockfd,recvline,1024,0,&serv,&len)>0)
        {
                        fputs(recvline,stdout);
                        memset(recvline,0,sizeof(recvline));
        }
}


void* copyto(void* arg)
{
        struct sockaddr *servaddr=(struct sockaddr*)arg;
        char sendline[1024]={0};
        while(fgets(sendline,1024,fp)!=NULL)
        {
                sendto(sockfd,sendline,strlen(sendline),0,servaddr,sizeof(*servaddr));
                memset(sendline,0,sizeof(sendline));
        }
        //shutdown(sockfd,SHUT_WR);
        return (NULL);
}


int main()
{
        struct sockaddr_in servaddr;
        int sockfd;
        sockfd=socket(AF_INET,SOCK_DGRAM,0);
        if(sockfd==-1)
                ERR_EXIT("socket");
        memset(&servaddr,0,sizeof(servaddr));
        servaddr.sin_family=AF_INET;
        servaddr.sin_port=2525;
        servaddr.sin_addr.s_addr=inet_addr("###");
//      connect(sockfd,(struct sockaddr*)&servaddr,sizeof(servaddr));           
        str_cli(stdin,sockfd,(struct sockaddr*)&servaddr,sizeof(servaddr));
        close(sockfd);
        return 0;
}