#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "uthash.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>

struct user_struct 
{
  int id;       //用户ID
  uint32_t ip;  //用户IP,以IP为索引
  UT_hash_handle hh;
};

//initialize to NULL
struct user_struct *users = NULL;

//add user information
void add_user(uint32_t user_ip, int user_id)
{
    struct user_struct *s;
    HASH_FIND_INT(users, &user_ip, s);  /*ip already in the hash? */
    if(s == NULL)
    {
        s = (struct user_struct *)malloc(sizeof *s);
        s->ip = user_ip;   
        HASH_ADD_INT(users, ip, s); 
    }
    s->id = user_id;  
}

//find user information
struct user_struct *find_user(uint32_t user_ip)
{
    struct user_struct *s;
    HASH_FIND_INT(users, &user_ip, s);
    return s;
}

void delete_user(struct user_struct *user) 
{
    HASH_DEL(users, user);  /* user: pointer to delete */
    free(user);            
}

//delect all uesr'informations
void delete_all() 
{
  struct user_struct *current_user, *tmp;
  HASH_ITER(hh, users, current_user, tmp) 
  {
    HASH_DEL(users,current_user);  /* delete; users advances to next */
    free(current_user);           
  }
}

//printf user information
void print_users()
{
    struct user_struct *s;
    char str[32];
    for(s=users; s != NULL; s=(struct user_struct*)(s->hh.next)) 
    {  
        //printf("user ip %s: user id %d\n", s->ip, s->id);
        inet_ntop(AF_INET, (void *)&s->ip, str, 32);
        printf(" user_ip: %s user_id: %d \n", str, s->id);
    }
}