crypto/heimdal-0.6.3/lib/roken/inet_ntop.c

   1 /*
   2  * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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 RCSID("$Id: inet_ntop.c,v 1.5 2001/04/04 23:58:01 assar Exp $");
  37 #endif
  38
  39 #include <roken.h>
  40
  41 /*
  42  *
  43  */
  44
  45 static const char *
  46 inet_ntop_v4 (const void *src, char *dst, size_t size)
  47 {
  48     const char digits[] = "0123456789";
  49     int i;
  50     struct in_addr *addr = (struct in_addr *)src;
  51     u_long a = ntohl(addr->s_addr);
  52     const char *orig_dst = dst;
  53
  54     if (size < INET_ADDRSTRLEN) {
  55         errno = ENOSPC;
  56         return NULL;
  57     }
  58     for (i = 0; i < 4; ++i) {
  59         int n = (a >> (24 - i * 8)) & 0xFF;
  60         int non_zerop = 0;
  61
  62         if (non_zerop || n / 100 > 0) {
  63             *dst++ = digits[n / 100];
  64             n %= 100;
  65             non_zerop = 1;
  66         }
  67         if (non_zerop || n / 10 > 0) {
  68             *dst++ = digits[n / 10];
  69             n %= 10;
  70             non_zerop = 1;
  71         }
  72         *dst++ = digits[n];
  73         if (i != 3)
  74             *dst++ = '.';
  75     }
  76     *dst++ = '\0';
  77     return orig_dst;
  78 }
  79
  80 #ifdef HAVE_IPV6
  81 static const char *
  82 inet_ntop_v6 (const void *src, char *dst, size_t size)
  83 {
  84     const char xdigits[] = "0123456789abcdef";
  85     int i;
  86     const struct in6_addr *addr = (struct in6_addr *)src;
  87     const u_char *ptr = addr->s6_addr;
  88     const char *orig_dst = dst;
  89
  90     if (size < INET6_ADDRSTRLEN) {
  91         errno = ENOSPC;
  92         return NULL;
  93     }
  94     for (i = 0; i < 8; ++i) {
  95         int non_zerop = 0;
  96
  97         if (non_zerop || (ptr[0] >> 4)) {
  98             *dst++ = xdigits[ptr[0] >> 4];
  99             non_zerop = 1;
 100         }
 101         if (non_zerop || (ptr[0] & 0x0F)) {
 102             *dst++ = xdigits[ptr[0] & 0x0F];
 103             non_zerop = 1;
 104         }
 105         if (non_zerop || (ptr[1] >> 4)) {
 106             *dst++ = xdigits[ptr[1] >> 4];
 107             non_zerop = 1;
 108         }
 109         *dst++ = xdigits[ptr[1] & 0x0F];
 110         if (i != 7)
 111             *dst++ = ':';
 112         ptr += 2;
 113     }
 114     *dst++ = '\0';
 115     return orig_dst;
 116 }
 117 #endif /* HAVE_IPV6 */
 118
 119 const char *
 120 inet_ntop(int af, const void *src, char *dst, size_t size)
 121 {
 122     switch (af) {
 123     case AF_INET :
 124         return inet_ntop_v4 (src, dst, size);
 125 #ifdef HAVE_IPV6
 126     case AF_INET6 :
 127         return inet_ntop_v6 (src, dst, size);
 128 #endif
 129     default :
 130         errno = EAFNOSUPPORT;
 131         return NULL;
 132     }
 133 }