usr/src/lib/libbc/libc/inet/inet_addr.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1987 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28           /* from UCB 4.5 82/11/14 */
  29
  30 #include <sys/types.h>
  31 #include <ctype.h>
  32 #include <netinet/in.h>
  33
  34 /*
  35  * Internet address interpretation routine.
  36  * All the network library routines call this
  37  * routine to interpret entries in the data bases
  38  * which are expected to be an address.
  39  * The value returned is in network order.
  40  */
  41 u_long
  42 inet_addr(cp)
  43         register char *cp;
  44 {
  45         register u_long val, base, n;
  46         register char c;
  47         u_long parts[4], *pp = parts;
  48
  49 again:
  50         /*
  51          * Collect number up to ``.''.
  52          * Values are specified as for C:
  53          * 0x=hex, 0=octal, other=decimal.
  54          */
  55         val = 0; base = 10;
  56         if (*cp == '0') {
  57                 if (*++cp == 'x' || *cp == 'X')
  58                         base = 16, cp++;
  59                 else
  60                         base = 8;
  61         }
  62         while (c = *cp) {
  63                 if (isdigit(c)) {
  64                         if ((c - '0') >= base)
  65                             break;
  66                         val = (val * base) + (c - '0');
  67                         cp++;
  68                         continue;
  69                 }
  70                 if (base == 16 && isxdigit(c)) {
  71                         val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
  72                         cp++;
  73                         continue;
  74                 }
  75                 break;
  76         }
  77         if (*cp == '.') {
  78                 /*
  79                  * Internet format:
  80                  *      a.b.c.d
  81                  *      a.b.c   (with c treated as 16-bits)
  82                  *      a.b     (with b treated as 24 bits)
  83                  */
  84                 if (pp >= parts + 4)
  85                         return (-1);
  86                 *pp++ = val, cp++;
  87                 goto again;
  88         }
  89         /*
  90          * Check for trailing characters.
  91          */
  92         if (*cp && !isspace(*cp))
  93                 return (-1);
  94         *pp++ = val;
  95         /*
  96          * Concoct the address according to
  97          * the number of parts specified.
  98          */
  99         n = pp - parts;
 100         switch (n) {
 101
 102         case 1:                         /* a -- 32 bits */
 103                 val = parts[0];
 104                 break;
 105
 106         case 2:                         /* a.b -- 8.24 bits */
 107                 val = (parts[0] << 24) | (parts[1] & 0xffffff);
 108                 break;
 109
 110         case 3:                         /* a.b.c -- 8.8.16 bits */
 111                 val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
 112                         (parts[2] & 0xffff);
 113                 break;
 114
 115         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 116                 val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
 117                       ((parts[2] & 0xff) << 8) | (parts[3] & 0xff);
 118                 break;
 119
 120         default:
 121                 return (-1);
 122         }
 123         val = htonl(val);
 124         return (val);
 125 }