哈希表1

Posted 2020-10-09

#include <string.h>  /* strcpy */  
#include <stdlib.h>  /* malloc */  
#include <stdio.h>   /* printf */  
#include "uthash.h"  

#define MAX_USERNAME_LEN      (30)
#define MAX_PHONENUM_LEN      (30)
#define ERROR_PARAMETER       (-1)
#define ERROR_USER_EXISTS     (-2)
#define ERROR_USER_NOT_EXISTS (-3)
#define SUCCESS               (0)

typedef struct UserAndPhone
{
    char userName[MAX_USERNAME_LEN];
    char phoneNumber[MAX_PHONENUM_LEN]; 
}UserAndPhone;

typedef struct PhoneBook 
{  
    char userName[MAX_USERNAME_LEN];      /* key */  
    char phoneNumber[MAX_PHONENUM_LEN];  
    UT_hash_handle hh;                    /* makes this structure hashable */  
}PhoneBook;  

PhoneBook* users = NULL;                  /* 用户及电话的哈希表 */
UserAndPhone* userAndPhone = NULL;        /* 存放遍历的用户及电话 */
int userCnt = 0;                          /* 存放用户数 */

/*******************************************************************
****功    能：将新的用户、电话号码插入到哈希表
****输入参数：phoneBook存放用户名、电话号码和哈希句柄，该参数由用户动态申请内存
****返 回 值：-1参数错误，-2用户已存在、0添加成功
*******************************************************************/
int InsertUserAndPhone(PhoneBook* phoneBook)
{
    if ((NULL == phoneBook)
     || (NULL == phoneBook->userName)
     || (NULL == phoneBook->phoneNumber)
     || (0 == strlen(phoneBook->userName))
     || (0 == strlen(phoneBook->phoneNumber)))
    {
        printf("error parameter.\n");
        return ERROR_PARAMETER;
    }
    
    PhoneBook* tmp;
    HASH_FIND_STR(users, phoneBook->userName, tmp);

    if (NULL != tmp)
    {
        printf("the userName[%s] already exist.\n", phoneBook->userName);
        return ERROR_USER_EXISTS;
    }
    
    HASH_ADD_KEYPTR(hh, users, phoneBook->userName, strlen(phoneBook->userName), phoneBook);  

    ++userCnt;

    return SUCCESS;
}

/****************************************************************************************
******功    能：根据用户名查找电话号码
******输入参数：userName表示要查询的用户名
******          phoneNumberFound 用来存放查找到的电话号码（由调用者保证空间足够大）
******返 回 值：-1参数错误，-3用户不存在，0找到
*****************************************************************************************/
int findPhoneNumber(char* userName, char *phoneNumberFound)
{
    if ((NULL == userName) 
    || (0 == strlen(userName))
    || (NULL == phoneNumberFound))
    {
        printf("invalid parameter.\n");
        return ERROR_PARAMETER;
    }
    
    PhoneBook* tmp;
    HASH_FIND_STR(users, userName, tmp);
    
    if (NULL == tmp)
    {
        printf("the userName[%s] does not exist.\n", userName);
        return ERROR_USER_NOT_EXISTS;
    }
    else
    {    
        strcpy(phoneNumberFound, tmp->phoneNumber);
        
        return SUCCESS;
    }
    

}