/*
 * Helper functions for test programs.
 * Copyright © 2012, 2022 Nick Bowler
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <getopt.h>

#include "common.h"
#include "help.h"

/*
 * Decode a hexadecimal string into a sequence of bytes.  If there are an
 * odd number of nibbles, treat the first character as the least significant
 * nibble of the first byte.  The result is written to the buffer specified by
 * buf.  At most n bytes are written to the buffer.
 *
 * Returns the number of bytes that would be written provided that n was large
 * enough, or (size_t)-1 if the input is not valid.
 */
size_t test_decode_hex(const char *hex, unsigned char *buf, size_t n)
{
	size_t len, count = 0;
	char tmp[] = "00";

	for (len = 0; hex[len]; len++) {
		if (!isxdigit((unsigned char)hex[len]))
			return -1;
	}

	if (!len)
		return 0;

	switch (len % 2) {
		while (len > 0) {
			case 0: tmp[0] = *hex++; len--;
			case 1: tmp[1] = *hex++; len--;

			if (count < n)
				buf[count] = strtoul(tmp, NULL, 16);
			count++;
		}
	}

	return count;
}

void test_print_version(const char *program)
{
	printf("%s (%s) %s\n", program, PACKAGE_NAME, PACKAGE_VERSION);
	puts("Copyright (C) 2022 Nick Bowler.");
	puts("License GPLv3+: GNU GPL version 3 or any later version.");
	puts("This is free software: you are free to change and redistribute it.");
	puts("There is NO WARRANTY, to the extent permitted by law.");
}

void test_print_options(const struct option *lopts)
{
	const struct option *opt;

	puts("\nOptions:");
	for (opt = lopts; opt->val; opt++) {
		if (help_print_optstring(opt, "ARG", 20))
			putchar('\n');
	}
}