bidirectional converter between gray and binary

graybin.c

/**
 * @file graybin.c
 * @author Rodrigo Dornelles
 * @link https://en.wikipedia.org/wiki/Gray_code
 */

#include <stdio.h>
#include <stdint.h>

/**
 * @brief bidirectional converter between gray and binary
 * 
 * @param in 
 * @return uint32_t 
 */
uint32_t graybin(uint32_t in)
{
    uint32_t out = in >> 1;
    out ^= in;
    return out;
}

/**
 * @brief print boolean format
 * 
 * @param in 
 */
void printb(uint32_t in)
{
    uint8_t i = 31;

    do {
        putc('0' + ((in >> i) & 1), stdout);
    }
    while(i--);

    putc('\n', stdout);
}

int main()
{
    printb(graybin(0b11)); ///< [2] gray -> bin
    printb(graybin(0b10)); ///< [2] bin -> gray
    printb(graybin(graybin(0b11))); ///< [2] gray -> bin -> gray
    return 0;
}