APNS device token encode function

As you see in the apple web site, you should encode the device token in binary format. And the device token must be in network order ( that is, big endian order).

 

Actually, it's easy but U need to make sure it's in big endian order. Here U needn't consider the binary order in this simple way. I use it in my PUSH sender process.

 

/************************************
* Tools as :
* string to hex binary
***********************************/
 
inline uint8_t hex_int_value(char in);
uint8_t get_hex_value(char in_1, char in_2);
 
int get_device_token_binary(const char *token, char *binary)
{
    uint8_t a;
 
    char *p = (char*)token;
    char *r = binary;
 
    for(int i = 0; i < 64; i += 2) {
        if (isxdigit(*(p+i)) == 0 || isxdigit(*(p+i+1)) == 0) {
            return -1;
        }
        a = get_hex_value(*(p+i), *(p+i+1));
        memcpy(r++, &a, sizeof(uint8_t));
    }
    return 0;
}
uint8_t get_hex_value(char in_1, char in_2)
{
    uint8_t value = 0;
 
    uint8_t val_high = hex_int_value(in_1);
    uint8_t val_low  = hex_int_value(in_2);
 
    return val_high * 16 + val_low;
}
 
inline uint8_t hex_int_value(char in)
{
    if (in >= '0' && in <= '9') {
        return (in - '0');
    } else if (in >= 'a' && in <= 'f') {
        return (in - 'a' + 10);
    } else {
        return 0;
    }
}

    If you find sth wrong or some better way, pls tell me.  Thx.