• 数据库 数据库编程二


    //头文件
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <errno.h>
    #include <mysql/mysql.h>
    #include <termios.h>
    
    #ifdef __cplusplus
    extern "C"
    {
    #endif
    //设置退格键不回显
    int set_Backkey();
    
    //获取用户SQL语句,判断用户操作,不区分大小写
    void read_user_print(MYSQL *pmysql,MYSQL *connection);
    
    #ifdef __cplusplus
    }
    #endif
    //辅助方法实现
    #include "pub.h"
    
    //设置退格键不回显
    int set_Backkey()
    {
        struct termios term;
        memset(&term, 0, sizeof(term));
        /*获取当前系统的termios设置*/
        if (tcgetattr(STDIN_FILENO, &term) == -1)
        {
            printf("tcgetattr() failed! error message:%s
    ", strerror(errno));
            return -1;
        }
        /*设置tremios的擦除字符功能为退格键*/
        term.c_cc[VERASE] = '';
        if (tcsetattr(STDIN_FILENO, TCSANOW, &term) == -1)
        {
            printf("tcsetattr() failed! error message:%s
    ", strerror(errno));
            return -1;
        }
        return 0;
    }
    
    //获取用户SQL语句,判断用户操作,不区分大小写
    void read_user_print(MYSQL *pmysql, MYSQL *connection)
    {
        if (connection == NULL || pmysql == NULL)
        {
            printf("read_user_print() params not correct!
    ");
            return;
        }
        /*等待用户控制台输入*/
        //获取数据库名称
        char buf_mysql[100] = { 0 };
        strcpy(buf_mysql, "mysql1>");
        int i = 0,j = 0;
        char temp_buf[1024] = { 0 };
        while (1)
        {
            /*显示mysql1>*/
            write(STDOUT_FILENO, buf_mysql, sizeof(buf_mysql));
            /*等待用户输入*/
            char buf_read[1024] = { 0 };
            read(STDIN_FILENO, buf_read, sizeof(buf_read));
            /*执行用户SQL*/
            /*判断用户输入的是查询操作,还是更新操作,
             * 更新操作有 update,delete,use,set,insert
             * 注意不区分大小写匹配
             * 将用户所有输入都转化为大写,遇到空格结束
             * */
            memset(temp_buf,0,sizeof(temp_buf));
            strcpy(temp_buf, buf_read);
            for (i=0; i < strlen(temp_buf); i++)
            {
                //如果当前字符不是空格
                if (temp_buf[i] != ' ')
                {
                    if (temp_buf[i] > 96 && temp_buf[i] < 123)
                    {
                        /*小写转化成大写*/
                        temp_buf[i] = temp_buf[i] - 32;
                    }
                } else
                {
                    break;
                }
            }
            int flag = 0;
            if (strncmp(temp_buf, "UPDATE", 6) == 0)
            {
                flag = 1;
            } else if (strncmp(temp_buf, "DELETE", 6) == 0)
            {
                flag = 1;
            } else if (strncmp(temp_buf, "USE", 3) == 0)
            {
                flag = 1;
            } else if (strncmp(temp_buf, "SET", 3) == 0)
            {
                flag = 1;
            } else if (strncmp(temp_buf, "INSERT", 6) == 0)
            {
                flag = 1;
            }
            //执行mysql_query()
            if (mysql_query(connection, buf_read) != 0)
            {
                printf("SQL error:%s
    ", mysql_error(pmysql));
                break;
            }
            if (flag)
            {
                printf("SQL 更新成功!
    ");
            } else
            {
                //执行查询语句
                MYSQL_RES *result = mysql_store_result(connection);
                if (result == NULL)
                {
                    printf("mysql_store_result() failed !
    ");
                    break;
                }
                MYSQL_ROW row;
                MYSQL_FIELD *field;
                /*展示列数据*/
                int numx = 0;
                while (1)
                {
                    field = mysql_fetch_field(result);
                    if (field == NULL)
                        break;
                    printf("%s	", field->name);
                    numx++;
                }
                printf("
    ");
                while (1)
                {
                    row = mysql_fetch_row(result);
                    if (row == NULL)
                        break;
                    /*打印一行中每一列的数据*/
                    for (j=0; j < numx; j++)
                    {
                        printf("%s	", row[j]);
                    }
                    /*每行换行*/
                    printf("
    ");
                }
                //释放查询结果集
                mysql_free_result(result);
            }
            printf("
    ");
        }
    }
    //mysql客户端实现
    #include "pub.h"
    
    int main(int arg, char *args[])
    {
        //mysql -h 192.168.1.101 -u dbuser1 -p
        if (arg < 4)
        {
            printf("please print three params!
    ");
            return -1;
        }
        char hostname[100] = { 0 };
        char username[100] = { 0 };
        char passwd[100] = { 0 };
        //char dbname[100] = { 0 };
        if (strncmp(args[1], "-h", 2) == 0)
        {
            strcpy(hostname, args[1]);
            strcpy(username, args[4]);
        } else if (strncmp(args[1], "-u", 2) == 0)
        {
            strcpy(hostname, "localhost");
            strcpy(username, args[2]);
        } else
        {
            printf("error print!");
            return -1;
        }
        //获取密码
        strcpy(passwd, getpass("Enter password: "));
        //设置退格键不回显
        if (set_Backkey() < 0)
        {
            printf("设置退格键不回显失败!
    ");
        }
        //创建mysql connection
        MYSQL mysql, *connection=NULL;
        //init mysql
        mysql_init(&mysql);
        //connect mysql server
        connection = mysql_real_connect(&mysql, hostname, username, passwd, "", 0,
                0, 0);
        if (connection == NULL)
        {
            printf("mysql_real_connect() failed ! error message:%s
    ",
                    mysql_error(&mysql));
            return -1;
        }
        /*用户输入*/
        read_user_print(&mysql,connection);
        //close sql server
        mysql_close(connection);
        return 0;
    }
    .SUFFIXES:.c .o
    CC=gcc
    SRCS=tec01.c
        pub.c
    OBJS=$(SRCS:.c=.o)
    EXEC=runsql
    
    start:$(OBJS)
        $(CC) -o $(EXEC) $(OBJS) -lmysqlclient
        @echo "-------OK----------"
    .c.o:
        $(CC) -Wall -g -o $@ -c $<
    clean:
        rm -f $(OBJS)
        rm -f $(EXEC)
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  • 原文地址:https://www.cnblogs.com/zhanggaofeng/p/6049268.html
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