adr2asc.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 88 行

/*
 * Copyright 1996 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that both the above copyright notice and this
 * permission notice appear in all copies, that both the above
 * copyright notice and this permission notice appear in all
 * supporting documentation, and that the name of M.I.T. not be used
 * in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  M.I.T. makes
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 * 
 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      $ANA: addr2ascii.c,v 1.1 1996/06/13 18:41:46 wollman Exp $
 *
 *  $Id: addr2ascii.c,v 1.2 1998/08/20 21:56:23 joel Exp $
 */

#include "socket.h"

#if defined(USE_BSD_FUNC)

/*-
 * Convert a network address from binary to printable numeric format.
 * This API is copied from INRIA's IPv6 implementation, but it is a
 * bit bogus in two ways:
 *
 *      1) There is no value in passing both an address family and
 *         an address length; either one should imply the other,
 *         or we should be passing sockaddrs instead.
 *      2) There should by contrast be /added/ a length for the buffer
 *         that we pass in, so that programmers are spared the need to
 *         manually calculate (read: ``guess'') the maximum length.
 *
 * Flash: the API is also the same in the NRL implementation, and seems to
 * be some sort of standard, so we appear to be stuck with both the bad
 * naming and the poor choice of arguments.
 */
char *addr2ascii (int af, const void *addrp, int len, char *buf)
{
  static char staticbuf[64];    /* 64 for AF_LINK > 16 for AF_INET */

  if (!buf)
     buf = staticbuf;

  switch (af)
  {
    case AF_INET:
         if (len != sizeof (struct in_addr))
         {
           SOCK_ERR (ENAMETOOLONG);
           return (NULL);
         }
         strcpy (buf, inet_ntoa (*(const struct in_addr *) addrp));
         break;

    case AF_LINK:
         if (len != sizeof (struct sockaddr_dl))
         {
           SOCK_ERR (ENAMETOOLONG);
           return (NULL);
         }
         strcpy (buf, link_ntoa ((const struct sockaddr_dl *) addrp));
         break;

    default:
         SOCK_ERR (EPROTONOSUPPORT);
         return (NULL);
  }
  return (buf);
}
#endif