#include <stdio.h>
#include <time.h>

unsigned int ip2long(const char *ip){
        unsigned int a, b, c, d;
        unsigned int ret;
        int num = sscanf(ip, "%d.%d.%d.%d", &a, &b, &c, &d);
        if(num == 4){
                ret = (a << 24) + (b << 16) + (c << 8) + d;
        }else{
                ret = 0;
        }
        return ret;
}

int long2ip(unsigned int intip, char *str, int str_len){
        if(!str){
                return -1;
        }
        int a, b, c, d;
        a = (intip & 0xff000000) >> 24;
        b = (intip & 0x00ff0000) >> 16;
        c = (intip & 0x0000ff00) >> 8;
        d = intip & 0x000000ff;
        snprintf(str, str_len, "%d.%d.%d.%d", a, b, c, d);
        return 0;
}

int main(){
        const char *ip = "222.234.255.189";
        unsigned ret;

        ret = ip2long(ip);
        printf("ip2long=%u\n", ret);

        char str[512];
        long2ip(ret, str, sizeof(str));
        printf("long2ip=%s\n", str);
}