9.7（UDP局域网多客户端聊天室）

本文主要是介绍9.7（UDP局域网多客户端聊天室），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

服务器端

#include<myhead.h>
#define SERIP "192.168.0.132"
#define SERPORT 8888
#define MAX 50
//定义用户结构体
typedef struct{struct sockaddr_in addr;int flag;
}User;User users[MAX];//用户列表void add_user(struct sockaddr_in *client){// 检查用户是否已经在列表中for (int i = 0; i < MAX; i++) {if (users[i].flag == 1 && memcmp(&users[i].addr, client, sizeof(struct sockaddr_in)) == 0) {// 用户已经在列表中return;}}for(int i=0;i<MAX;i++){if(users[i].flag==0){users[i].addr = *client;users[i].flag = 1;break;}}
}//向用户转发消息，排除发送者
void transform(char *buff,struct sockaddr_in *send,int oldfd){for(int i=0;i<MAX;i++){if(users[i].flag!=0){if(memcmp(&users[i].addr,send,sizeof(struct sockaddr_in))!=0){sendto(oldfd,buff,strlen(buff),0,(struct sockaddr *)&users[i].addr,sizeof(users[i].addr));}}}}int main (int argc, const char *argv[])
{//定义套接字int oldfd = socket(AF_INET,SOCK_DGRAM,0);if(oldfd==-1){perror("oldfd");return -1;}int kkk=2; if(setsockopt(oldfd,SOL_SOCKET,SO_BROADCAST,&kkk,sizeof(kkk))==-1){ perror("setsockopt"); return -1;} //绑定端口struct sockaddr_in server = {.sin_family = AF_INET,.sin_addr.s_addr = inet_addr(SERIP),.sin_port = htons(SERPORT)};int server_len = sizeof(server);if(bind(oldfd,(struct sockaddr *)&server,server_len)==-1){perror("bind");return -1;}printf("UDP聊天服务器启动，端口号为：%d\n",SERPORT);//IO多路复用struct pollfd fds[1];fds[0].fd = oldfd;fds[0].events = POLLIN;char buff[1024];struct sockaddr_in client;int client_len = sizeof(client);while(1){int poll_count = poll(fds,1,-1);if(fds[0].revents == POLLIN){memset(buff,0,sizeof(buff));int len = recvfrom(oldfd,buff,sizeof(buff),0,(struct sockaddr *)&client,&client_len);if(len == 0){perror("recvfrom");return -1;}buff[len] = '\0';printf("接收到来自%s:%d的消息%s\n",inet_ntoa(client.sin_addr),ntohs(client.sin_port),buff);//添加用户到列表add_user(&client);//转发给其他用户transform(buff,&client,oldfd);}}close(oldfd);return 0;
}

客户端

#include<myhead.h>
#define SERIP "192.168.0.132"
#define SERPORT 8888
#define MAX 50int main (int argc, const char *argv[])
{//创建套接字int oldfd = socket(AF_INET,SOCK_DGRAM,0);if(oldfd==-1){perror("oldfd");return -1;}struct sockaddr_in server={.sin_family = AF_INET,.sin_port = htons(SERPORT),.sin_addr.s_addr = inet_addr(SERIP)};struct sockaddr_in client;int client_len = sizeof(client);int server_len = sizeof(server);printf("UDP客户端启动，连接到服务器%s:%d\n",inet_ntoa(server.sin_addr),ntohs(server.sin_port));char message[20] = "UDP客户端连接";sendto(oldfd,message,strlen(message),0,(struct sockaddr *)&server,server_len);struct pollfd fds[2];fds[0].fd = oldfd;fds[0].events = POLLIN;fds[1].fd = 0;fds[1].events = POLLIN;char buff[1024];while(1){int poll_count = poll(fds,2,5000);if(poll_count == -1){perror("poll_count");return -1;}if(poll_count == 0){continue;}if(fds[0].revents == POLLIN){memset(buff,0,sizeof(buff));int len = recvfrom(oldfd,buff,sizeof(buff),0,(struct sockaddr *)&server,&server_len);if(len<0){perror("recvfrom");continue;}buff[len]='\0';printf("服务器发来消息:%s\n",buff);}if(fds[1].revents==POLLIN){memset(buff,0,sizeof(buff));if(fgets(buff,sizeof(buff),stdin)!=NULL){buff[strlen(buff)-1]='\0';sendto(oldfd,buff,strlen(buff),0,(struct sockaddr *)&server,server_len);}}}close(oldfd);return 0;
}