/******************************************************************************
Converting HEX bytes into flat string
Credits to @Jonathan Leffler and @Jens
*******************************************************************************/
#include <stdio.h>
const unsigned char * MAC_HEX_TO_STR(char *MAC_ADDR);
int main()
{
char *MAC_ADDR = "\x00\x22\xC7\xFF\xFF\x27";
/* Working solution #1
char str[13];
char *MAC_ADDR_NEW = str;
%02x%02x%02x%02x%02x%02x // Small char
%.2X%.2X%.2X%.2X%.2X%.2X // Capital char
snprintf(str, sizeof(str), "%.2X%.2X%.2X%.2X%.2X%.2X", (unsigned char)MAC_ADDR[0], (unsigned char)MAC_ADDR[1], (unsigned char)MAC_ADDR[2], (unsigned char)MAC_ADDR[3], (unsigned char)MAC_ADDR[4], (unsigned char)MAC_ADDR[5]);
printf(" ==>> %s\n ", MAC_ADDR_NEW);
*/
/* Working solution #2
char *MAC_ADDR = "\x00\x22\xC7\xFF\xFF\x27";
char *MAC_ADDR_NEW;
asprintf (&MAC_ADDR_NEW, "%02x%02x%02x%02x%02x%02x",
(uint8_t)MAC_ADDR[0], (uint8_t)MAC_ADDR[1], (uint8_t)MAC_ADDR[2],
(uint8_t)MAC_ADDR[3], (uint8_t)MAC_ADDR[4], (uint8_t)MAC_ADDR[5]);
printf("%s\n", MAC_ADDR_NEW);
free(MAC_ADDR_NEW); // Good software hygiene is to free what you allocate.
*/
const unsigned char* test = MAC_HEX_TO_STR(MAC_ADDR);
printf(" 2==>> %s\n ", test);
return 0;
}
const unsigned char * MAC_HEX_TO_STR(char *MAC_ADDR){
// If static is not used, due to local variable is destroyed out of the function will return gibberish!
static char str[13];
static char *MAC_ADDR_NEW = str;
//%02x%02x%02x%02x%02x%02x // Small char
//%.2X%.2X%.2X%.2X%.2X%.2X // Capital char
snprintf(str, sizeof(str), "%.2X%.2X%.2X%.2X%.2X%.2X", (unsigned char)MAC_ADDR[0], (unsigned char)MAC_ADDR[1], (unsigned char)MAC_ADDR[2], (unsigned char)MAC_ADDR[3], (unsigned char)MAC_ADDR[4], (unsigned char)MAC_ADDR[5]);
//printf(" RETURNED_MAC ==>> %s\n ", MAC_ADDR_NEW);
//MAC_ADDR_NEW[13] = 0; // I don't know, I tried with or wirhout but no difference observed!
return MAC_ADDR_NEW;
}
