网络聊天室编写（基于UDP）
服务器
#include <myhead.h>#define PORT 8888 //端口号：接收方绑定的端口号
#define IP "192.168.114.56" //本机IP#define ERR_MSG(msg) do{\fprintf(stderr, "__%d__:", __LINE__); \perror(msg);\
}while(0)//需要传入到分支线程的参数
typedef struct Climsg{char code;char user[32];char text[128];
}msg_t;//创建链表存储数据
typedef struct Node{struct sockaddr_in addr; struct Node *next;
}node_t,*nodeptr; //创建节点的函数
int create_node(nodeptr *phead){*phead = (nodeptr)malloc(sizeof(node_t));if(NULL == *phead){printf("内存分配失败\n");exit(-1);}(*phead)->next=NULL;return 0;
}
//尾插法
int insert_data_by_tail(node_t *phead,struct sockaddr_in addr){if(NULL == phead){printf("参数为NULL,请检查\n");return -1;}//将新客户端使用尾插法插入链表中nodeptr pnew = NULL;create_node(&pnew);pnew->addr = addr; nodeptr ptemp =phead;while(ptemp->next != NULL){ptemp = ptemp->next;}//让尾结点的指针域指向新节点ptemp->next = pnew;return 0;
}int main(int argc, const char *argv[])
{int sfd = 0;if(-1==(sfd=socket(AF_INET,SOCK_DGRAM,0))){ERR_MSG("socket error");}struct sockaddr_in sin;memset(&sin,0,sizeof(sin));sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);socklen_t sin_len = sizeof(sin);if(-1 == bind(sfd,(struct sockaddr *)&sin,sin_len)){ERR_MSG("bind error");} struct sockaddr_in cin,temp_cin;memset(&cin,0,sizeof(cin));socklen_t cin_len = sizeof(cin);char name[32] = {0};pid_t pid = 0;msg_t msg;msg_t msg_send;//创建头结点nodeptr phead;create_node(&phead);phead->addr = cin;if(-1 == (pid = fork())){ERR_MSG("fork error");}else if(0 == pid){ //子进程 接收数据 （1、d 登录操作 2、q 群聊操作 3、t 退出操作） while(1){memset(&msg,0,sizeof(msg));if(-1 == recvfrom(sfd, (void*)&msg, sizeof(msg),0, (struct sockaddr *)&cin,&cin_len)){perror("recv error");} switch(msg.code){case 'd':printf("用户[%s]上线\n", msg.user); insert_data_by_tail(phead,cin);nodeptr q=phead->next; while(q != NULL){msg.code='d';if(-1 == sendto(sfd,&msg,sizeof(msg),0,(struct sockaddr *)&q->addr,sizeof(q->addr))){ERR_MSG("send error");}q=q->next;}break; case 'q': if(strcmp("系统提示",msg.user)!=0){printf("[%s]:%s\n",msg.user, msg.text);}node_t *p = phead->next; while(p != NULL){msg.code='q';if(-1 == sendto(sfd,(void *)&msg,sizeof(msg),0,(struct sockaddr *)&p->addr,sizeof(p->addr))){ERR_MSG("send error");}p=p->next;} break; case 't': printf("用户[%s]:已退出\n", msg.user);nodeptr t = phead; nodeptr pdel = NULL; while(t->next != NULL){msg.code='t';if( 0 == memcmp(&(t->next->addr), &cin,sizeof(cin))){pdel = t->next;t->next = pdel->next;free(pdel);}else{t = t->next;if(-1 == sendto(sfd, &msg,sizeof(msg),0,(struct sockaddr *)&t->addr,sizeof(t->addr))){ERR_MSG("send error");}} } break;}}}else if(0 < pid){//父进程 发送系统消息while(1){ strcpy(msg_send.user,"系统");memset(msg_send.text,0,128);fgets(msg_send.text,128,stdin);msg_send.text[strlen(msg_send.text)-1] = '\0';msg_send.code = 'q'; if(-1 == sendto(sfd,&msg_send,sizeof(msg_send),0,(struct sockaddr *)&sin,sin_len)){ERR_MSG("send error"); } }} kill(pid, SIGKILL);wait(NULL);//给子进程回收资源exit(0); close(sfd);return 0;
}
客户端
#include <myhead.h>#define PORT 8888 //端口号：接收方绑定的端口号#define ERR_MSG(msg) do{\fprintf(stderr, "__%d__:", __LINE__); \perror(msg);\
}while(0)
#define IP "192.168.114.56" //本机IP，ifconfig
#define M 32
#define N 128
typedef struct _Node{struct sockaddr_in addr;struct _Node *next;
}node_t;typedef struct _Msg{char code;char user[M];char text[N];
}msg_t;int main(int argc, const char *argv[])
{//创建用户数据报套接字int sockfd = socket(AF_INET, SOCK_DGRAM, 0);if (-1 == sockfd){ERR_MSG("socket error");}//填充服务器网络信息结构体struct sockaddr_in sin;memset(&sin, 0, sizeof(sin));sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);socklen_t sin_len = sizeof(sin);int res = 0;char name[32]={0};msg_t msg;pid_t pid;struct sockaddr_in cin;memset(&cin,0,sizeof(cin));socklen_t cin_len = sizeof(cin);//输入用户名，完成登陆操作printf("请输入登录信息：");msg.code = 'd';memset(msg.user, 0, 32);fgets(name, 32, stdin);//在终端获取用户名strcpy(msg.user,name);msg.user[strlen(msg.user) - 1] = '\0';if (-1 == sendto(sockfd,&msg,sizeof(msg),0, (struct sockaddr *)&sin,sin_len)){ //给服务器发送用户名ERR_MSG("send error");}//创建进程if(-1 == (pid = fork())){ERR_MSG("fork error");}else if(0 == pid){ //子进程 接收数据 while (1){memset(&msg,0,sizeof(msg));//接收服务器的应答if (-1 == (res=recvfrom(sockfd, &msg, sizeof(msg), 0,(struct sockaddr *)&sin,&sin_len))){ERR_MSG("recv error");} if(strcmp(msg.user,name) == -10){ continue;}else{//打印应答信息switch(msg.code){case 'd':printf("用户[%s]登录上线了....\n", msg.user); break; case 'q':printf("[%s]:%s\n",msg.user,msg.text);break;case 't': printf("用户[%s]已退出\n", msg.user); break;} } } }else if(0 < pid){//父进程 发送数据（2、q:群聊操作 3、t:退出操作）while(1){//在终端获取群聊memset(msg.text, 0, 128);fgets(msg.text, 128, stdin);msg.text[strlen(msg.text) - 1] = '\0'; //清空结尾的 '\n' if( 0 ==strcmp(msg.text, "quit")){msg.code = 't'; if (-1 == sendto(sockfd, &msg, sizeof(msg), 0,(struct sockaddr *)&sin,sin_len)){ERR_MSG("send error"); } break;}else{msg.code = 'q'; }//给服务器发送群聊消息if (-1 == sendto(sockfd, &msg, sizeof(msg), 0,(struct sockaddr *)&sin,sin_len)){ERR_MSG("send error");}} } //关闭套接字close(sockfd);return 0;
}
