bin2hex.c

#include <stdlib.h>
//
// bin2hex
// Returns the hexadecimal representation of a bytes sequence.
// Parameters
// - bin: array of bytes
// - size: number of bytes in bin.
// Returns
// A string containing the hex representation of bin.
//
char *bin2hex(u_int8_t *bin, int size){
    const char *hexdigits = "0123456789abcdef";
    char *str = (char*) malloc(sizeof(char) * (size * 2 + 1));
    if(!str) return NULL;
    for (int i = 0; i < size; i++){
        uint8_t v = bin[i];
        uint8_t v2 = v & 0x0F;
        uint8_t v1 = v >> 4;
        str[2*i] = hexdigits[v1];
        str[2*i + 1] = hexdigits[v2];
    }
    str[size*2] = '\0';
    return str;
}