Linux下在线词典项目学习
在线词典要实现的功能：
- 在线词典
- 项目功能描述
- 用户注册和登录验证
- 服务器端将用户信息和历史记录保存在数据库中，客户端输入用户名和密码，服务器端在数据库中查找、匹配，返回结果
- 单次在线翻译
- 根据客户端输入的单次在字典文件中搜索
- 历史记录查询
- 项目分析
词典功能展示：
- 注册用户
-
登录
-
查询单词
-
历史记录
-
支持多客户端同时连接服务器查询单词
服务器流程图：
客户端流程图：
代码
点击查看代码
/**
* @file client.c
* @brief ./client serv_ip serv_port
* @author
* @version
* @date 2022-08-09
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#define N 32
#define R 1 //user - register
#define L 2 //user - login
#define Q 3 //user - query
#define H 4 //user - history
//定义通信双方的信息结构体
typedef struct {
int type;
char name[N];
char data[256];
}MSG;
int do_register(int sockfd,MSG *msg); //register
int do_login(int sockfd,MSG *msg); //login
int do_query(int sockfd,MSG *msg); //query
int do_history(int sockfd,MSG *msg); //history
int main(int argc,const char *argv[])
{
int sockfd;
struct sockaddr_in serveraddr;
int n;
MSG msg;
if (argc != 3){ //服务器IP 端口号
printf("Usage: %s server ip port.\n",argv[0]);
return -1;
}
// 创建socket
if ((sockfd = socket(AF_INET,SOCK_STREAM,0)) < 0){
perror("fail to socket.\n");
return -1;
}
// 服务器地址
bzero(&serveraddr,sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_addr.s_addr = inet_addr(argv[1]);
serveraddr.sin_port = htons(atoi(argv[2]));
// connect服务器
if(connect(sockfd,(struct sockaddr *)&serveraddr,sizeof(serveraddr))){
perror("fail to connect");
return -1;
}
// 一级菜单
while(1)
{
printf("****************************************\n");
printf("* 1.register 2.login 3.quit *\n");
printf("****************************************\n");
printf("Please chose:");
scanf("%d",&n);
while (getchar() != '\n'){}
switch(n)
{
case 1:
do_register(sockfd,&msg);
break;
case 2:
if(do_login(sockfd,&msg) == 1){
goto next; //登录成功 跳转二级菜单
}
break;
case 3:
close(sockfd);
exit(0);
break;
default:
printf("Invalid data cmd.\n");
}
}
next: //二级菜单
while(1)
{
printf("************************************************\n");
printf("* 1.query_word 2.history_record 3.quit *\n");
printf("************************************************\n");
printf("Please chose:");
scanf("%d",&n);
while (getchar() != '\n'){}
switch(n)
{
case 1:
do_query(sockfd,&msg);
break;
case 2:
do_history(sockfd,&msg);
break;
case 3:
close(sockfd);
exit(0);
break;
default:
printf("Invalid data cmd.\n");
}
}
return 0;
}
int do_register(int sockfd,MSG *msg)
{
msg->type = R;
printf("Input name: ");
scanf("%s",msg->name);
getchar();
printf("Input passwd: ");
scanf("%s",msg->data);
getchar();
if (send(sockfd,msg,sizeof(MSG),0) < 0 ){
perror("send");
return -1;
}
if (recv(sockfd,msg,sizeof(MSG),0) < 0){
perror("recv");
return -1;
}
// 打印客户端返回信息 OK! 或者 usr alread exist.
printf("%s\n",msg->data);
return 0;
}
int do_login(int sockfd,MSG *msg)
{
msg->type = L;
printf("Input name: ");
scanf("%s",msg->name);
getchar();
printf("Input passwd: ");
scanf("%s",msg->data);
getchar();
if (send(sockfd,msg,sizeof(MSG),0) < 0 ){
perror("send");
return -1;
}
if (recv(sockfd,msg,sizeof(MSG),0) < 0){
perror("recv");
return -1;
}
// 判断服务器 返回值是否为OK
if(strncmp(msg->data,"OK",3) == 0){
printf("Login OK!\n");
return 1;
}
else{
printf("%s\n",msg->data);
}
return 0;
}
int do_query(int sockfd,MSG *msg)
{
msg->type = Q;
puts("----------------------");
while(1){
printf("Input word(# means quit): ");
scanf("%s",msg->data);
getchar();
//输入#号 返回上一级菜单
if(strncmp(msg->data,"#",1) == 0)
break;
//将要查询的单词传送给服务器
if(send(sockfd,msg,sizeof(MSG),0) <0){
perror("send");
return -1;
}
// 等待接收服务器 传回的单词注释信息
if (recv(sockfd,msg,sizeof(MSG),0) < 0){
perror("recv");
return -1;
}
// 打印单词解释
printf("%s\n",msg->data);
}
return 0;
}
int do_history(int sockfd,MSG *msg)
{
msg->type = H;
send(sockfd,msg,sizeof(MSG),0);
// 接收服务器传递的历史记录信息
while(1){
recv(sockfd,msg,sizeof(MSG),0);
if(msg->data[0] == '\0')
break;
// 打印历史记录信息
printf("%s\n",msg->data);
}
return 0;
}
点击查看代码
/**
* @file server.c
* @brief ./server
* @author
* @version
* @date 2022-08-09
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sqlite3.h>
#include <signal.h>
#include <time.h>
#define N 32
#define SERV_PORT 10000 //服务器 端口号
#define R 1 //user - register
#define L 2 //user - login
#define Q 3 //user - query
#define H 4 //user - history
#define DATABASE "my.db"
//定义通信双方的信息结构体
typedef struct {
int type;
char name[N];
char data[256];
}MSG;
int do_client(int acceptfd,sqlite3 *db); //do_client
void do_register(int acceptfd,MSG *msg,sqlite3 *db); //register
int do_login(int acceptfd,MSG *msg,sqlite3 *db); //login
int do_serachword(MSG *msg,char word[]);
int get_date(char *date);
int do_query(int acceptfd,MSG *msg,sqlite3 *db); //query
int history_callback(void *arg,int f_num,char **f_value,char **f_name);
int do_history(int acceptfd,MSG *msg,sqlite3 *db); //history
int main(int argc,const char *argv[])
{
int sockfd;
struct sockaddr_in serveraddr;
int n;
MSG msg;
sqlite3 *db;
int acceptfd;
pid_t pid;
char *errmsg;
// 打开数据库
if (sqlite3_open(DATABASE,&db) != SQLITE_OK){
printf("%s\n",sqlite3_errmsg(db));
return -1;
}
else
printf("Open DATABASE success.\n");
// 创建usr表
if (sqlite3_exec(db,"create table if not exists usr(name text primary key,pass text);",NULL,NULL,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
}
// 创建record表
if (sqlite3_exec(db,"create table if not exists record(name text,data text,word text);",NULL,NULL,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
}
// 创建socket
if ((sockfd = socket(AF_INET,SOCK_STREAM,0)) < 0){
perror("socket");
return -1;
}
// 服务器地址
bzero(&serveraddr,sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_addr.s_addr = htonl(INADDR_ANY); //服务器IP INADDR_ANY获取
serveraddr.sin_port = htons(SERV_PORT); //端口
// bind()
if(bind(sockfd,(struct sockaddr *)&serveraddr,sizeof(serveraddr)) < 0){
perror("bind");
return -1;
}
// listen
if (listen(sockfd,5) < 0)
{
perror("listen");
return -1;
}
//处理僵尸进程
signal(SIGCHLD,SIG_IGN); //忽略子进程状态信息，自动回收僵尸进程
while(1)
{
if((acceptfd = accept(sockfd,NULL,NULL)) < 0){
perror("accept");
return -1;
}
if ((pid = fork()) < 0){
perror("fork");
return -1;
}
else if (pid == 0){ //子进程 处理客户端具体请求
close(sockfd);
do_client(acceptfd,db);
}
else //父进程 接收客户端请求
{
close(acceptfd);
}
}
return 0;
}
//do_client函数
int do_client(int acceptfd,sqlite3 *db)
{
MSG msg;
while (recv(acceptfd,&msg,sizeof(MSG),0) > 0){
printf("type: %d\n",msg.type);
switch(msg.type)
{
case R:
do_register(acceptfd,&msg,db);
break;
case L:
do_login(acceptfd,&msg,db);
break;
case Q:
do_query(acceptfd,&msg,db);
break;
case H:
do_history(acceptfd,&msg,db);
break;
default:
printf("Invalid data msg.\n");
}
}
printf("Client exit.\n");
close(acceptfd);
exit(0);
return 0;
}
void do_register(int acceptfd,MSG *msg,sqlite3 *db)
{
char *errmsg;
char sql[sizeof(MSG)+128];
sprintf(sql,"insert into usr values('%s','%s');",msg->name,msg->data);
printf("%s\n",sql);
if (sqlite3_exec(db,sql,NULL,NULL,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
strcpy(msg->data,"usr name already exist.\n");
}
else{
printf("Client register ok!\n");
strcpy(msg->data,"OK!");
}
if(send(acceptfd,msg,sizeof(MSG),0) < 0){
perror("send");
return;
}
return;
}
int do_login(int acceptfd,MSG *msg,sqlite3 *db)
{
char sql[sizeof(MSG)+128] = {};
char *errmsg;
int nrow;
int ncloumn;
char **resultp;
// 根据 用户名和密码 查询数据库usr
sprintf(sql,"select * from usr where name = '%s' and pass ='%s';",msg->name,msg->data);
printf("%s\n",sql);
if (sqlite3_get_table(db,sql,&resultp,&nrow,&ncloumn,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
return -1;
}
// 查询成功，数据库中拥有此用户 发送OK
//nrow只可能是 0或者1
if(nrow == 1){
strcpy(msg->data,"OK");
send(acceptfd,msg,sizeof(MSG),0);
return 1;
}
// 密码或者用户名错误
if (nrow == 0){
strcpy(msg->data,"usr or passwd is wrong.");
send(acceptfd,msg,sizeof(MSG),0);
}
return 0;
}
//do_serachword函数
int do_serachword(MSG *msg,char word[])
{
FILE *fp;
int len = 0;
char temp[512] = {};
int result;
char *p;
//打开词典文件
if((fp = fopen("dict.txt","r")) == NULL){
perror("fopen");
strcpy(msg->data,"Failed to open dict.txt\n");
return -1;
}
len = strlen(word);
printf("%s,len=%d\n",word,len);
//按行读取词典文件，比对查询单词
while(fgets(temp,512,fp) != NULL){
result = strncmp(temp,word,len); //词典中单词出现的具有先后顺序 比较词典和传入单词
if(result < 0) //temp < word 证明word还在temp单词的下面 继续查找
continue;
if((result > 0) || (result ==0 && temp[len] != ' ')) //两种情况证明没有这个word 1是temp > word 2是 如temp为anc 要查询单词为an，此时result为0，但显然没有找到该单词
break;
// 找到了要查询单词所在的行，取出注释 如abide v.遵守
p = temp + len; // v.遵守
while(*p == ' ') //去除空格 v.遵守
p++;
strcpy(msg->data,p);
printf("%s\n",msg->data);
//注释拷贝完成后 关闭文件
fclose(fp);
return 1;
}
fclose(fp);
return 0;
}
//获取本地时间
int get_date(char *date)
{
time_t t;
struct tm *tp;
time(&t);
tp = localtime(&t);
// 格式化输出时间到date
sprintf(date,"%d-%02d-%02d %02d:%02d:%02d",tp->tm_year + 1900,tp->tm_mon + 1,tp->tm_mday,tp->tm_hour,tp->tm_min,tp->tm_sec);
return 0;
}
int do_query(int acceptfd,MSG *msg,sqlite3 *db)
{
char word[64];
int found = 0;
char date[128];
char sql[512] = {};
char *errmsg;
strcpy(word,msg->data);
found = do_serachword(msg,word); //具体查找单词 在do_searchword中实现
// found=1 表示找到了单词，此时需保存 用户名，查询时间，单词 到历史记录表中
if (found ==1){
get_date(date); //获取时间
sprintf(sql,"insert into record values('%s','%s','%s');",msg->name,date,word);
printf("%s\n",sql);
if(sqlite3_exec(db,sql,NULL,NULL,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
return -1;
}
}
else //没有查到单词
strcpy(msg->data,"Not found word!\n");
// 发送查询结果到客户端
send(acceptfd,msg,sizeof(MSG),0);
return 0;
}
// 利用回调函数 得到查询结果 并将历史记录发送个客户端
int history_callback(void *arg,int f_num,char **f_value,char **f_name)
{
// record表中有 name date word
int acceptfd;
MSG msg;
acceptfd = *(int *)arg;
sprintf(msg.data,"%s , %s",f_value[1],f_value[2]);
send(acceptfd,&msg,sizeof(MSG),0);
return 0;
}
int do_history(int acceptfd,MSG *msg,sqlite3 *db)
{
char sql[128] = {};
char *errmsg;
sprintf(sql,"select * from record where name = '%s';",msg->name);
// 查询数据库
if (sqlite3_exec(db,sql,history_callback,(void *)&acceptfd,&errmsg) != SQLITE_OK){
printf("%s\n",errmsg);
}
else
printf("Query record done.\n");
// 所有记录查询完成后给客户端发送一个结束信息
msg->data[0] = '\0';
send(acceptfd,msg,sizeof(MSG),0);
return 0;
}
本文来自博客园，作者：{Ray963}，转载请注明原文链接：{https://www.cnblogs.com/ray93/}
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