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 #ifdef HAVE_CONFIG_H
  35 # include <config.h>
  36 #endif
  37
  38 #if defined(LIBC_SCCS) && !defined(lint)
  39 static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
  40 #endif /* LIBC_SCCS and not lint */
  41
  42 #include <ctype.h>
  43
  44 #ifdef __MINGW32__
  45 /* Include for MinGW only.  Cygwin will have the latter. */
  46 #include <winsock2.h>
  47 #else
  48 #include <sys/param.h>
  49 #include <netinet/in.h>
  50 #include <arpa/inet.h>
  51 #endif
  52
  53 #if 0
  54
  55 /*
  56  * Ascii internet address interpretation routine.
  57  * The value returned is in network order.
  58  */
  59 u_long
  60 inet_addr(const char *cp)
  61 {
  62         struct in_addr val;
  63
  64         if (inet_aton(cp, &val))
  65                 return (val.s_addr);
  66         return (INADDR_NONE);
  67 }
  68
  69 #endif
  70
  71 /* We provide this prototype to avoid compiler warnings.  If this ever
  72    conflicts with a declaration in a system header file, we'll find
  73    out, because we should include that header file here.  */
  74 int inet_aton (const char *cp, struct in_addr *addr);
  75
  76 /*
  77  * Check whether "cp" is a valid ascii representation
  78  * of an Internet address and convert to a binary address.
  79  * Returns 1 if the address is valid, 0 if not.
  80  * This replaces inet_addr, the return value from which
  81  * cannot distinguish between failure and a local broadcast address.  */
  82 int
  83 inet_aton(const char *cp_arg, struct in_addr *addr)
  84 {
  85         register unsigned long val;
  86         register int base, n;
  87         register unsigned char c;
  88         register unsigned const char *cp = (unsigned const char *) cp_arg;
  89         unsigned int parts[4];
  90         register unsigned int *pp = parts;
  91
  92         for (;;) {
  93                 /*
  94                  * Collect number up to ``.''.
  95                  * Values are specified as for C:
  96                  * 0x=hex, 0=octal, other=decimal.
  97                  */
  98                 val = 0; base = 10;
  99                 if (*cp == '0') {
 100                         if (*++cp == 'x' || *cp == 'X')
 101                                 base = 16, cp++;
 102                         else
 103                                 base = 8;
 104                 }
 105                 while ((c = *cp) != '\0') {
 106                         if (isascii(c) && isdigit(c)) {
 107                                 val = (val * base) + (c - '0');
 108                                 cp++;
 109                                 continue;
 110                         }
 111                         if (base == 16 && isascii(c) && isxdigit(c)) {
 112                                 val = (val << 4) +
 113                                         (c + 10 - (islower(c) ? 'a' : 'A'));
 114                                 cp++;
 115                                 continue;
 116                         }
 117                         break;
 118                 }
 119                 if (*cp == '.') {
 120                         /*
 121                          * Internet format:
 122                          *      a.b.c.d
 123                          *      a.b.c   (with c treated as 16-bits)
 124                          *      a.b     (with b treated as 24 bits)
 125                          */
 126                         if (pp >= parts + 3 || val > 0xff)
 127                                 return (0);
 128                         *pp++ = val, cp++;
 129                 } else
 130                         break;
 131         }
 132         /*
 133          * Check for trailing characters.
 134          */
 135         if (*cp && (!isascii(*cp) || !isspace(*cp)))
 136                 return (0);
 137         /*
 138          * Concoct the address according to
 139          * the number of parts specified.
 140          */
 141         n = pp - parts + 1;
 142         switch (n) {
 143
 144         case 1:                         /* a -- 32 bits */
 145                 break;
 146
 147         case 2:                         /* a.b -- 8.24 bits */
 148                 if (val > 0xffffff)
 149                         return (0);
 150                 val |= parts[0] << 24;
 151                 break;
 152
 153         case 3:                         /* a.b.c -- 8.8.16 bits */
 154                 if (val > 0xffff)
 155                         return (0);
 156                 val |= (parts[0] << 24) | (parts[1] << 16);
 157                 break;
 158
 159         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 160                 if (val > 0xff)
 161                         return (0);
 162                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 163                 break;
 164         }
 165         if (addr)
 166                 addr->s_addr = htonl(val);
 167         return (1);
 168 }
 169
 170 /*
 171   Local Variables:
 172   c-file-style: "gnu"
 173   End:
 174 */