/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*******************************************************************************
 * The following function pr_inet_aton is based on the BSD function inet_aton
 * with some modifications. The license and copyright notices applying to this
 * function appear below. Modifications are also according to the license below.
 ******************************************************************************/

#include "prnetdb.h"

/*
 * Copyright (c) 1983, 1990, 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.
 * 4. 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.
 */

/*
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#define XX 127
static const unsigned char index_hex[256] = {
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    0, 1, 2, 3,  4, 5, 6, 7,  8, 9,XX,XX, XX,XX,XX,XX,
    XX,10,11,12, 13,14,15,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,10,11,12, 13,14,15,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
    XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX, XX,XX,XX,XX,
};

static PRBool _isdigit(char c) {
    return c >= '0' && c <= '9';
}
static PRBool _isxdigit(char c) {
    return index_hex[(unsigned char) c] != XX;
}
static PRBool _isspace(char c) {
    return c == ' ' || (c >= '\t' && c <= '\r');
}
#undef XX

int
pr_inet_aton(const char *cp, PRUint32 *addr)
{
    PRUint32 val;
    int base, n;
    char c;
    PRUint8 parts[4];
    PRUint8 *pp = parts;
    int digit;

    c = *cp;
    for (;;) {
        /*
         * Collect number up to ``.''.
         * Values are specified as for C:
         * 0x=hex, 0=octal, isdigit=decimal.
         */
        if (!_isdigit(c)) {
            return (0);
        }
        val = 0; base = 10; digit = 0;
        if (c == '0') {
            c = *++cp;
            if (c == 'x' || c == 'X') {
                base = 16, c = *++cp;
            }
            else {
                base = 8;
                digit = 1;
            }
        }
        for (;;) {
            if (_isdigit(c)) {
                if (base == 8 && (c == '8' || c == '9')) {
                    return (0);
                }
                val = (val * base) + (c - '0');
                c = *++cp;
                digit = 1;
            } else if (base == 16 && _isxdigit(c)) {
                val = (val << 4) + index_hex[(unsigned char) c];
                c = *++cp;
                digit = 1;
            } else {
                break;
            }
        }
        if (c == '.') {
            /*
             * Internet format:
             *    a.b.c.d
             *    a.b.c    (with c treated as 16 bits)
             *    a.b    (with b treated as 24 bits)
             */
            if (pp >= parts + 3 || val > 0xffU) {
                return (0);
            }
            *pp++ = val;
            c = *++cp;
        } else {
            break;
        }
    }
    /*
     * Check for trailing characters.
     */
    if (c != '\0' && !_isspace(c)) {
        return (0);
    }
    /*
     * Did we get a valid digit?
     */
    if (!digit) {
        return (0);
    }
    /*
     * Concoct the address according to
     * the number of parts specified.
     */
    n = pp - parts + 1;
    switch (n) {
        case 1:                /*%< a -- 32 bits */
            break;

        case 2:                /*%< a.b -- 8.24 bits */
            if (val > 0xffffffU) {
                return (0);
            }
            val |= (unsigned int)parts[0] << 24;
            break;

        case 3:                /*%< a.b.c -- 8.8.16 bits */
            if (val > 0xffffU) {
                return (0);
            }
            val |= ((unsigned int)parts[0] << 24) | ((unsigned int)parts[1] << 16);
            break;

        case 4:                /*%< a.b.c.d -- 8.8.8.8 bits */
            if (val > 0xffU) {
                return (0);
            }
            val |= ((unsigned int)parts[0] << 24) |
                   ((unsigned int)parts[1] << 16) |
                   ((unsigned int)parts[2] << 8);
            break;
    }
    *addr = PR_htonl(val);
    return (1);
}