/*	$NetBSD: inet_network.c,v 1.5 2022/10/06 06:03:06 ryo Exp $	*/

/*
 * Copyright (c) 1983, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)inet_network.c	8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: inet_network.c,v 1.5 2022/10/06 06:03:06 ryo Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <assert.h>
#include <ctype.h>
#ifdef _DIAGNOSTIC
#include <stddef.h>	/* for NULL */
#endif

#ifdef __weak_alias
__weak_alias(inet_network,_inet_network)
#endif

/*
 * Internet network address interpretation routine.
 * The library routines call this routine to interpret
 * network numbers.
 */
in_addr_t
inet_network(const char *cp)
{
	in_addr_t val;
	size_t i, n;
	u_char c;
	in_addr_t parts[4], *pp = parts;
	int digit, base;

	_DIAGASSERT(cp != NULL);

again:
	val = 0; base = 10; digit = 0;
	if (*cp == '0') {
		digit = 1, base = 8, cp++;
		if (*cp == 'x' || *cp == 'X')
			digit = 0, base = 16, cp++;
	}
	while ((c = *cp) != 0) {
		if (isdigit(c)) {
			if (base == 8 && (c == '8' || c == '9'))
				return (INADDR_NONE);
			val = (val * base) + (c - '0');
			cp++;
			digit = 1;
			continue;
		}
		if (base == 16 && isxdigit(c)) {
			val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
			cp++;
			digit = 1;
			continue;
		}
		break;
	}
	if (!digit)
		return (INADDR_NONE);
	if (pp >= parts + 4 || val > 0xff)
		return (INADDR_NONE);
	if (*cp == '.') {
		*pp++ = val, cp++;
		goto again;
	}
	if (*cp && !isspace((u_char) *cp))
		return (INADDR_NONE);
	*pp++ = val;
	n = pp - parts;
	if (n > 4)
		return (INADDR_NONE);
	for (val = 0, i = 0; i < n; i++) {
		val <<= 8;
		val |= parts[i] & 0xff;
	}
	return (val);
}
