TCP/IP网络编程：第18章聊天室

服务端：负责连接客户端，转发客户端的信息给其他客户

客户端：发送信息给服务端，接收服务端传来的其他客户的信息

服务端代码：

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <pthread.h>
#define BUF_SIZE 100
#define MAX_CLNT 256

void *handle_clnt(void *arg);
void send_msg(char * msg,int len);
void error_handling(char *msg);

int clnt_cnt=0;
int clnt_socks[MAX_CLNT];
pthread_mutex_t mutx;
int main(int argc,char *argv[]){
    int serv_sock,clnt_sock;
    struct sockaddr_in serv_adr,clnt_adr;
    int clnt_adr_sz;
    pthread_t t_id;
    if(argc!=2){
        printf("Usage :%s<port>\n",argv[0]);
        exit(1);
    }

    pthread_mutex_init(&mutx,NULL);
    serv_sock=socket(PF_INET,SOCK_STREAM,0);

    memset(&serv_adr,0,sizeof(serv_adr));
    serv_adr.sin_family=AF_INET;
    serv_adr.sin_addr.s_addr=htonl(INADDR_ANY);
    serv_adr.sin_port=htons(atoi(argv[1]));

    if(bind(serv_sock,(struct sockaddr*)&serv_adr,sizeof(serv_adr))==-1)
    error_handling("bind()error");
    if(listen(serv_sock,5)==-1)
    error_handling("listen()error");

    while(1){
        clnt_adr_sz=sizeof(clnt_adr);
        clnt_sock=accept(serv_sock,(struct sockaddr*)&clnt_adr,&clnt_adr_sz);

        pthread_mutex_lock(&mutx);
        clnt_socks[clnt_cnt++]=clnt_sock;//存放连接的客户端套接字
        pthread_mutex_unlock(&mutx);

        pthread_create(&t_id,NULL,handle_clnt,(void*)&clnt_sock);
        pthread_detach(t_id);
        printf("Connect client IP:%s\n",inet_ntoa(clnt_adr.sin_addr));
    }
    close(serv_sock);
    return 0;
}

void *handle_clnt(void *arg){
    int clnt_sock=*((int*)arg);
    int str_len=0,i;
    char msg[BUF_SIZE];

    while((str_len=read(clnt_sock,msg,sizeof(msg)))!=0)
    send_msg(msg,str_len);
    pthread_mutex_lock(&mutx);
    for(i=0;i<clnt_cnt;i++){
        if(clnt_sock==clnt_socks[i])//remove disconnected client
        {
            while(i++<clnt_cnt-1)
            clnt_socks[i]=clnt_socks[i+1];
            break;
        }
    }
    clnt_cnt--;
    pthread_mutex_unlock(&mutx);
    close(clnt_sock);
    return NULL;
}

void send_msg(char *msg,int len){
    int i;
    pthread_mutex_lock(&mutx);
    for(i=0;i<clnt_cnt;i++){//send to all
        write(clnt_socks[i],msg,len);
    }
    pthread_mutex_unlock(&mutx);
}
void error_handling(char *message){
    fputs(message,stderr);
    fputc('\n',stderr);
    exit(1);
}

客户端代码：

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <pthread.h>
#define BUF_SIZE 100
#define NAME_SIZE 20

void *send_msg(void * arg);
void *recv_msg(void * arg);
void error_handling(char *msg);

char name[NAME_SIZE]="[DEFAULT]";
char msg[BUF_SIZE];

int main(int argc,char *argv[]){
    int sock;
    struct sockaddr_in serv_addr;
    pthread_t snd_thread,rcv_thread;
    void * thread_return;
    if(argc!=4){
        printf("Usage : %s<IP> <port><name>\n",argv[0]);
        exit(1);
    }

    sprintf(name,"[%s]",argv[3]);
    sock=socket(PF_INET,SOCK_STREAM,0);
    memset(&serv_addr,0,sizeof(serv_addr));
    serv_addr.sin_family=AF_INET;
    serv_addr.sin_addr.s_addr=inet_addr(argv[1]);
    serv_addr.sin_port=htons(atoi(argv[2]));

    if(connect(sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr))==-1)
    error_handling("connect()error");

    pthread_create(&snd_thread,NULL,send_msg,(void*)&sock);
    pthread_create(&rcv_thread,NULL,recv_msg,(void*)&sock);
    pthread_join(snd_thread,&thread_return);
    pthread_join(rcv_thread,&thread_return);
    close(sock);
    return 0;
}
void *send_msg(void *arg){
    int sock=*((int *)arg);
    char name_msg[NAME_SIZE+BUF_SIZE];
    while(1){
        fgets(msg,BUF_SIZE,stdin);
        if(!strcmp(msg,"q\n")||!strcmp(msg,"Q\n")){
            close(sock);
            exit(0);
        }
        sprintf(name_msg,"%s %s",name,msg);
        write(sock,name_msg,strlen(name_msg));
    }
    return NULL;
}
void * recv_msg(void *arg){
    int sock=*((int*)arg);
    char name_msg[NAME_SIZE+BUF_SIZE];
    int str_len;
    while(1){
        str_len=read(sock,name_msg,NAME_SIZE+BUF_SIZE-1);
        if(str_len==-1)
        return (void*)-1;
        name_msg[str_len]=0;
        fputs(name_msg,stdout);
    }
}
void error_handling(char *message){
    fputs(message,stderr);
    fputc('\n',stderr);
    exit(1);
}

编译允许：

其他两个客户端也是类似的，分别发送Hi Yoon反正就是基本上实现了一个群聊的功能