1  /*
       2   * Copyright (c) 1996,1999 by Internet Software Consortium.
       3   *
       4   * Permission to use, copy, modify, and distribute this software for any
       5   * purpose with or without fee is hereby granted, provided that the above
       6   * copyright notice and this permission notice appear in all copies.
       7   *
       8   * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
       9   * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
      10   * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
      11   * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
      12   * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
      13   * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
      14   * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
      15   * SOFTWARE.
      16   */
      17  
      18  #include <sys/types.h>
      19  #include <sys/socket.h>
      20  #include <netinet/in.h>
      21  #include <arpa/inet.h>
      22  
      23  #include <errno.h>
      24  #include <stdio.h>
      25  #include <string.h>
      26  
      27  #ifdef SPRINTF_CHAR
      28  # define SPRINTF(x) strlen(sprintf/**/x)
      29  #else
      30  # define SPRINTF(x) ((size_t)sprintf x)
      31  #endif
      32  
      33  /*
      34   * char *
      35   * inet_neta(src, dst, size)
      36   *	format a u_long network number into presentation format.
      37   * return:
      38   *	pointer to dst, or NULL if an error occurred (check errno).
      39   * note:
      40   *	format of ``src'' is as for inet_network().
      41   * author:
      42   *	Paul Vixie (ISC), July 1996
      43   */
      44  char *
      45  inet_neta (uint32_t src, char *dst, size_t size)
      46  {
      47  	char *odst = dst;
      48  	char *tp;
      49  
      50  	while (src & 0xffffffff) {
      51  		u_char b = (src & 0xff000000) >> 24;
      52  
      53  		src <<= 8;
      54  		if (b) {
      55  			if (size < sizeof "255.")
      56  				goto emsgsize;
      57  			tp = dst;
      58  			dst += SPRINTF((dst, "%u", b));
      59  			if (src != 0L) {
      60  				*dst++ = '.';
      61  				*dst = '\0';
      62  			}
      63  			size -= (size_t)(dst - tp);
      64  		}
      65  	}
      66  	if (dst == odst) {
      67  		if (size < sizeof "0.0.0.0")
      68  			goto emsgsize;
      69  		strcpy(dst, "0.0.0.0");
      70  	}
      71  	return (odst);
      72  
      73   emsgsize:
      74  	__set_errno (EMSGSIZE);
      75  	return (NULL);
      76  }