lib/libc/inet/inet_neta.c

   1 /*      $NetBSD: inet_neta.c,v 1.3 2012/06/25 22:32:44 abs Exp $        */
   2
   3 /*
   4  * Copyright (c) 1996 by Internet Software Consortium.
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  11  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  12  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  13  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  14  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  15  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  16  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  17  * SOFTWARE.
  18  */
  19
  20 #include <sys/cdefs.h>
  21 #if defined(LIBC_SCCS) && !defined(lint)
  22 #if 0
  23 static const char rcsid[] = "Id: inet_neta.c,v 8.2 1996/08/08 06:54:44 vixie Exp ";
  24 #else
  25 __RCSID("$NetBSD: inet_neta.c,v 1.3 2012/06/25 22:32:44 abs Exp $");
  26 #endif
  27 #endif
  28
  29 #include "namespace.h"
  30 #include <sys/types.h>
  31 #include <sys/socket.h>
  32 #include <netinet/in.h>
  33 #include <arpa/inet.h>
  34
  35 #include <assert.h>
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <string.h>
  39
  40 #ifdef __weak_alias
  41 __weak_alias(inet_neta,_inet_neta)
  42 #endif
  43
  44 /*
  45  * char *
  46  * inet_neta(src, dst, size)
  47  *      format a u_long network number into presentation format.
  48  * return:
  49  *      pointer to dst, or NULL if an error occurred (check errno).
  50  * note:
  51  *      format of ``src'' is as for inet_network().
  52  * author:
  53  *      Paul Vixie (ISC), July 1996
  54  */
  55 char *
  56 inet_neta(u_long src, char *dst, size_t size)
  57 {
  58         char *odst = dst;
  59         char *ep;
  60         int advance;
  61
  62         _DIAGASSERT(dst != NULL);
  63
  64         if (src == 0x00000000) {
  65                 if (size < sizeof "0.0.0.0")
  66                         goto emsgsize;
  67                 strlcpy(dst, "0.0.0.0", size);
  68                 return dst;
  69         }
  70         ep = dst + size;
  71         if (ep <= dst)
  72                 goto emsgsize;
  73         while (src & 0xffffffffUL) {
  74                 u_char b = (u_char)((src & 0xff000000UL) >> 24);
  75
  76                 src <<= 8;
  77                 if (b || src) {
  78                         advance = snprintf(dst, (size_t)(ep - dst), "%u", b);
  79                         if (advance <= 0 || advance >= ep - dst)
  80                                 goto emsgsize;
  81                         dst += advance;
  82                         if (src != 0L) {
  83                                 if (dst + 1 >= ep)
  84                                         goto emsgsize;
  85                                 *dst++ = '.';
  86                                 *dst = '\0';
  87                         }
  88                 }
  89         }
  90         return (odst);
  91
  92  emsgsize:
  93         errno = EMSGSIZE;
  94         return (NULL);
  95 }