/*      $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);
}