programming | Tricky

How to convert hexadecimal number to IP address in C++

When you need to convert hexadecimal number in C++ like 0DF52286 to standard IP address format like 13.245.34.134 you can use this code:

static char* hex_to_ip(const char *input)
{
    char *output = (char*)malloc(sizeof(char) * 16);
    unsigned int a, b, c, d;

    if (sscanf(input, "%2x%2x%2x%2x", &a, &b, &c, &d) != 4)
        return output;
    sprintf(output, "%u.%u.%u.%u", a, b, c, d);
    return output;
}

static char* hex_to_ip(const char *input)

{

char *output = (char*)malloc(sizeof(char) * 16);

unsigned int a, b, c, d;

if (sscanf(input, "%2x%2x%2x%2x", &a, &b, &c, &d) != 4)

return output;

sprintf(output, "%u.%u.%u.%u", a, b, c, d);

return output;

}

The method takes one argument which is the IP address in hexadecimal format.