jchat：linux聊天程序4：客户端

拼搏现实的明天。 2022-06-13 04:26 190阅读 0赞

# 转载地址：http://www.cnblogs.com/huanglianjing/p/4355258.html #

# makefile： #

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jchat:        main.o login.o regist.o tcp.o
        gcc -w main.o login.o regist.o tcp.o -o jchat
        rm -f *.o *.gch *~
    main.o:        main.c login.h regist.h tcp.h
        gcc -w -c main.c login.h regist.h tcp.h
    login.o:    login.c login.h tcp.h
        gcc -w -c login.c login.h tcp.h
    regist.o:    regist.c regist.h tcp.h
        gcc -w -c regist.c regist.h tcp.h
    tcp.o:        tcp.c tcp.h
        gcc -w -c tcp.c tcp.h
    
    clean:
        rm -f *.o *.gch *~ jchat

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main.c：

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/*client/main.c*/
    
    #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <string.h>
    
    #include "login.h"
    #include "regist.h"
    #include "tcp.h"
    
    #define MAXLINE 4096
    #define IP "127.0.0.1" // localhost
    #define PORT 12345
    
    char sendbuff[MAXLINE], recvbuff[MAXLINE];//send buffer & recv buffer
    int sockfd;//socket file descriptor
    
    int main(int argc, char *argv[])
    {
        if ((sockfd = link_server(IP, PORT)) == -1) {
            exit(1);
        }
    
        char choice[107];
        while (1) {
            printf("login or regist:");
            scanf("%s", choice);
            if (strcmp(choice, "login") == 0) {
                login(sockfd);
            }
            else if (strcmp(choice, "regist") == 0) {
                regist(sockfd);
            }
            else {
                puts("input login or regist!");
            }
        }
    }

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/*client/login.c*/
    
    #include <stdio.h>
    #include <unistd.h>
    #include <string.h>
    #include <stdlib.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <sys/un.h>
    
    #include "login.h"
    #include "tcp.h"
    
    #define MAXLINE 4096
    #define IP "127.0.0.1" // localhost
    #define PORT 12345
    
    char user[107], passwd[107];
    char line[107];
    
    /*
     * login to server
     * return 1 if succeed, 0 if fail
     */
    int login_succeed(int sockfd)
    {
        char sendbuff[MAXLINE], recvbuff[MAXLINE];
        sprintf(sendbuff, "l:%s:%s", user, passwd);
    
        write(sockfd, sendbuff, strlen(sendbuff));    
        //printf("sendbuff> '%s'\n", sendbuff);
        int n = read(sockfd, recvbuff, MAXLINE);
        recvbuff[n] = '\0';
        //printf("recvbuff> '%s'\n", recvbuff);
    
        if (strcmp(recvbuff, "y") == 0) return 1;
        else return 0;
    }
    
    /*
     * send message to another user by server
     */
    void send_mesg(int sockfd)
    {
        char sendbuff[MAXLINE];
        int len = strlen(line);
        int i = 1, j, k, pos;
    
        while (i<len && (line[i]==' ' || line[i]=='\t')) ++i;
        j = i + 1;
        while (j<len && line[j]!=' ' && line[j]!='\t') ++j;
        k = j + 1;
        while (k<len && (line[k]==' ' || line[k]=='\t')) ++k;
    
        int send_len = 2, ulen = strlen(user);
        sendbuff[0] = 's';sendbuff[1] = ':';
        for (pos=0; pos<ulen; ++pos) sendbuff[send_len++] = user[pos];
        sendbuff[send_len++] = ':';
        for (pos=i; pos<j; ++pos) sendbuff[send_len++] = line[pos];
        sendbuff[send_len++] = ':';
        for (pos=k; pos<len; ++pos) sendbuff[send_len++] = line[pos];
        sendbuff[send_len++] = '\0';
    
        write(sockfd, sendbuff, strlen(sendbuff));
        //printf("send_mesg sendbuff> '%s'\n", sendbuff);
    }
    
    /*
     * ask the server the online user
     */
    void check_online(int sockfd)
    {
        char sendbuff[MAXLINE], recvbuff[MAXLINE];
        sprintf(sendbuff, "o");
    
        write(sockfd, sendbuff, strlen(sendbuff));
        //printf("check_online sendbuff> '%s'\n", sendbuff);
        int recv_len = read(sockfd, recvbuff, MAXLINE);
        recvbuff[recv_len] = '\0';
        //printf("check_online recvbuff> '%s'\n", recvbuff);
    
        if (recv_len <= 1) {
            printf("no one online\n");
        }
        else {
            int i = 0, j, k, num = 0;
            char on[100][21];
            while (i < recv_len) {
                j = i+1;
                while (recvbuff[j] != ';') ++j;
                for (k=i; k<j; ++k) on[num][k-i] = recvbuff[k];
                on[num][j-i] = '\0';
                ++num;
                i = j + 1;
            }
            printf("%d online user:\n", num);
            for (k=0; k<num; ++k) printf("  %s\n", on[k]);
        }
    }
    
    /*
     * quit this client
     * quit the process fork by server
     */
    void quit(int sockfd)
    {
        char sendbuff[MAXLINE];
        sprintf(sendbuff, "q:%s", user);
    
        write(sockfd, sendbuff, strlen(sendbuff));
        //printf("quit sendbuff> '%s'\n", sendbuff);
    }
    
    /*
     * get unread message from server every 1 second
     */
    void get_mesg(int sockfd)
    {
        char sendbuff[MAXLINE], recvbuff[MAXLINE];
    
        while (1) {
            sleep(1);
    
            sprintf(sendbuff, "g:%s", user);
            write(sockfd, sendbuff, strlen(sendbuff));
    
            //printf("get_mesg sendbuff> '%s'\n", sendbuff);
            int recv_len = read(sockfd, recvbuff, MAXLINE);
            recvbuff[recv_len] = '\0';
            //printf("get_mesg recvbuff> '%s'\n", recvbuff);
    
            if (recv_len <= 1) { // no message get
                continue;
            }
    
            int num, i, j, k, l;
            num = i = 0;
            char on[100][21];
            while (i < recv_len) {
                j = i + 1;
                while (recvbuff[j] != ';') ++j;
    
                k = i;
                while (k<j && recvbuff[k]!=':') ++k;
                int line_len = 0;
                for (l=i; l<k; ++l) line[line_len++] = recvbuff[l];
                line[line_len++] = ':';line[line_len++] = ' ';
                for (l=k+1; l<j; ++l) line[line_len++] = recvbuff[l];
                line[line_len] = '\0';
                puts(line);
    
                i = j + 1;
            }
        }
    }
    
    /*
     * send online notice to server every 5 seconds
     */
    void online_notice(int sockfd)
    {
        char sendbuff[MAXLINE];
    
        while (1) {
            sprintf(sendbuff, "a:%s", user);
    
            write(sockfd, sendbuff, strlen(sendbuff));
            //printf("sendbuff> '%s'\n", sendbuff);
    
            sleep(5);
        }
    }
    
    /*
     * everything after login
     * thread 1 : receive user command
     * thread 2 : get unread message from server
     * thread 3 : send online notice to server
     */
    void login(int sockfd)
    {
        printf("user: ");
        scanf("%s", user);
        printf("password: ");
        scanf("%s", passwd);
    
        if (login_succeed(sockfd)) {
            printf("welcome %s~\n", user);
            pid_t pid1 = fork();
            if (pid1 != 0) {
                pid_t pid2 = fork();
                if (pid2 != 0) { // thread 1 : input command
                    while (gets(line)) {
                        switch (line[0]) {
                            case 's': // send message
                                send_mesg(sockfd);
                                break;
                            case 'o': // check online
                                check_online(sockfd);
                                break;
                            case 'q': // quit
                                quit(sockfd);
                                kill(pid1, 9);
                                kill(pid2, 9);
                                printf("goobye %s ~\n", user);
                                exit(0);
                                break;
                        }
                    }
                }
                else { // thread 2 : get message from server
                    get_mesg(sockfd);
                }
            }
            else { // thread 3 : send online notice
                online_notice(sockfd);
            }
        }
        else {
            printf("login failed\n");
        }
    }

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/*client/login.h*/
    
    #ifndef LOGIN_H
    #define LOGIN_H
    
    void login(int sockfd);
    
    #endif // LOGIN_H

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regist.c：注册操作

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/*client/regist.c*/
    
    #include <stdio.h>
    #include <unistd.h>
    #include <string.h>
    #include <stdlib.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <sys/un.h>
    
    #include "regist.h"
    #include "tcp.h"
    
    #define MAXLINE 4096
    
    extern char sendbuff[MAXLINE], recvbuff[MAXLINE];
    char user[107], passwd[107];
    
    /*
     * regist new user
     * return 1 if succeed, 0 if fail
     */
    int regist_succeed(int sockfd)
    {
        sprintf(sendbuff, "r:%s:%s", user, passwd);
    
        write(sockfd, sendbuff, strlen(sendbuff));
        int n = read(sockfd, recvbuff, MAXLINE);
        recvbuff[n] = 0;
    
        if (strcmp(recvbuff, "y") == 0) return 1;
        else return 0;
    }
    
    /*
     * regist
     */
    void regist(int sockfd)
    {
        printf("user: ");
        scanf("%s", user);
        printf("password: ");
        scanf("%s", passwd);
    
        if (regist_succeed(sockfd)) {
            printf("regist a new user!\n");
        }
        else {
            printf("fail in regist new user!\n");
        }
    }

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regist.h：

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/*client/regist.h*/
    
    #ifndef REGIST_H
    #define REGIST_H
    
    void regist(int sockfd);
    
    #endif // REGIST_H

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tcp.c：建立与服务器的连接

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/*client/tcp.c*/
    
    #include <stdio.h>
    #include <unistd.h>
    #include <string.h>
    #include <stdlib.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <sys/un.h>
    #include <netinet/in.h>
    
    #include "tcp.h"
    
    /*
     * link to assign IP and port
     * return the socket file descriptor
     */
    int link_server(char *IP, int port)
    {
        int sockfd;
        struct sockaddr_in servaddr;
    
        if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
            fprintf(stderr, "socket error\n");
            return -1;
        }
    
        memset(&servaddr, 0, sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons(port);
        if (inet_pton(AF_INET, IP, &servaddr.sin_addr) <= 0) {
            fprintf(stderr, "inet_pton error for %s\n", IP);
            return -1;
        }
    
        if (connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) < 0) {
            fprintf(stderr, "connect error\n");
            return -1;
        }
    
        return sockfd;
    }

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tcp.h：

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/*client/tcp.h*/
    
    #ifndef TCP_H
    #define TCP_H
    
    /*
     * link IP:port using tcp
     * return sock file descriptor of the link (-1 if error)
     */
    int link_server(char *IP, int port);
    
    #endif // TCP_H

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[copycode.gif]: /images/20220613/339d7bd735594262abe873511bc21291.png