libguile/inet_aton.c

   1 /*
   2  * Copyright (c) 1983, 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  35    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  36
  37 #if defined(LIBC_SCCS) && !defined(lint)
  38 static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 #include <ctype.h>
  42
  43 #ifdef __MINGW32__
  44 #include <winsock2.h>
  45 #else
  46 #include <sys/param.h>
  47 #include <netinet/in.h>
  48 #include <arpa/inet.h>
  49 #endif
  50
  51 #if 0
  52
  53 /*
  54  * Ascii internet address interpretation routine.
  55  * The value returned is in network order.
  56  */
  57 u_long
  58 inet_addr(const char *cp)
  59 {
  60         struct in_addr val;
  61
  62         if (inet_aton(cp, &val))
  63                 return (val.s_addr);
  64         return (INADDR_NONE);
  65 }
  66
  67 #endif
  68
  69 /* We provide this prototype to avoid compiler warnings.  If this ever
  70    conflicts with a declaration in a system header file, we'll find
  71    out, because we should include that header file here.  */
  72 int inet_aton (const char *cp, struct in_addr *addr);
  73
  74 /*
  75  * Check whether "cp" is a valid ascii representation
  76  * of an Internet address and convert to a binary address.
  77  * Returns 1 if the address is valid, 0 if not.
  78  * This replaces inet_addr, the return value from which
  79  * cannot distinguish between failure and a local broadcast address.  */
  80 int
  81 inet_aton(const char *cp_arg, struct in_addr *addr)
  82 {
  83         register unsigned long val;
  84         register int base, n;
  85         register unsigned char c;
  86         register unsigned const char *cp = (unsigned const char *) cp_arg;
  87         unsigned int parts[4];
  88         register unsigned int *pp = parts;
  89
  90         for (;;) {
  91                 /*
  92                  * Collect number up to ``.''.
  93                  * Values are specified as for C:
  94                  * 0x=hex, 0=octal, other=decimal.
  95                  */
  96                 val = 0; base = 10;
  97                 if (*cp == '0') {
  98                         if (*++cp == 'x' || *cp == 'X')
  99                                 base = 16, cp++;
 100                         else
 101                                 base = 8;
 102                 }
 103                 while ((c = *cp) != '\0') {
 104                         if (isascii(c) && isdigit(c)) {
 105                                 val = (val * base) + (c - '0');
 106                                 cp++;
 107                                 continue;
 108                         }
 109                         if (base == 16 && isascii(c) && isxdigit(c)) {
 110                                 val = (val << 4) +
 111                                         (c + 10 - (islower(c) ? 'a' : 'A'));
 112                                 cp++;
 113                                 continue;
 114                         }
 115                         break;
 116                 }
 117                 if (*cp == '.') {
 118                         /*
 119                          * Internet format:
 120                          *      a.b.c.d
 121                          *      a.b.c   (with c treated as 16-bits)
 122                          *      a.b     (with b treated as 24 bits)
 123                          */
 124                         if (pp >= parts + 3 || val > 0xff)
 125                                 return (0);
 126                         *pp++ = val, cp++;
 127                 } else
 128                         break;
 129         }
 130         /*
 131          * Check for trailing characters.
 132          */
 133         if (*cp && (!isascii(*cp) || !isspace(*cp)))
 134                 return (0);
 135         /*
 136          * Concoct the address according to
 137          * the number of parts specified.
 138          */
 139         n = pp - parts + 1;
 140         switch (n) {
 141
 142         case 1:                         /* a -- 32 bits */
 143                 break;
 144
 145         case 2:                         /* a.b -- 8.24 bits */
 146                 if (val > 0xffffff)
 147                         return (0);
 148                 val |= parts[0] << 24;
 149                 break;
 150
 151         case 3:                         /* a.b.c -- 8.8.16 bits */
 152                 if (val > 0xffff)
 153                         return (0);
 154                 val |= (parts[0] << 24) | (parts[1] << 16);
 155                 break;
 156
 157         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 158                 if (val > 0xff)
 159                         return (0);
 160                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 161                 break;
 162         }
 163         if (addr)
 164                 addr->s_addr = htonl(val);
 165         return (1);
 166 }
 167
 168 /*
 169   Local Variables:
 170   c-file-style: "gnu"
 171   End:
 172 */