inet_addr.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 1987 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/* from UCB 4.5 82/11/14 */
#include <sys/types.h>
#include <ctype.h>
#include <netinet/in.h>
/*
* Internet address interpretation routine.
* All the network library routines call this
* routine to interpret entries in the data bases
* which are expected to be an address.
* The value returned is in network order.
*/
u_long
inet_addr(cp)
register char *cp;
{
register u_long val, base, n;
register char c;
u_long parts[4], *pp = parts;
again:
/*
* Collect number up to ``.''.
* Values are specified as for C:
* 0x=hex, 0=octal, other=decimal.
*/
val = 0; base = 10;
if (*cp == '0') {
if (*++cp == 'x' || *cp == 'X')
base = 16, cp++;
else
base = 8;
}
while (c = *cp) {
if (isdigit(c)) {
if ((c - '0') >= base)
break;
val = (val * base) + (c - '0');
cp++;
continue;
}
if (base == 16 && isxdigit(c)) {
val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
cp++;
continue;
}
break;
}
if (*cp == '.') {
/*
* 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 + 4)
return (-1);
*pp++ = val, cp++;
goto again;
}
/*
* Check for trailing characters.
*/
if (*cp && !isspace(*cp))
return (-1);
*pp++ = val;
/*
* Concoct the address according to
* the number of parts specified.
*/
n = pp - parts;
switch (n) {
case 1: /* a -- 32 bits */
val = parts[0];
break;
case 2: /* a.b -- 8.24 bits */
val = (parts[0] << 24) | (parts[1] & 0xffffff);
break;
case 3: /* a.b.c -- 8.8.16 bits */
val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
(parts[2] & 0xffff);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
((parts[2] & 0xff) << 8) | (parts[3] & 0xff);
break;
default:
return (-1);
}
val = htonl(val);
return (val);
}