util.c

/* utility functions
 *
 * Copyright (c) 2014-16 Michael Gernoth <michael@gernoth.net>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include <inttypes.h>

uint8_t ascii_to_nibble(uint8_t a)
{
	uint8_t c = 0x00;

	if ((a >= '0') && (a <= '9')) {
		c = a - '0';
	} else if ((a >= 'A') && (a <= 'F')) {
		c = (a - 'A') + 10;
	} else if ((a >= 'a') && (a <= 'f')) {
		c = (a - 'a') + 10;
	}

	return c;
}

int validate_nibble(uint8_t a)
{
	if (((a >= '0') && (a <= '9')) ||
	    ((a >= 'A') && (a <= 'F')) ||
	    ((a >= 'a') && (a <= 'f')))
	    	return 1;

	return 0;
}

char nibble_to_ascii(uint8_t n)
{
	const uint8_t nibble[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
		'A', 'B', 'C', 'D', 'E', 'F'};

	return nibble[n];
}