inet/test-ifaddrs.c

   1 /* Test listing of network interface addresses.
   2    Copyright (C) 2002 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <ifaddrs.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27
  28 int
  29 main (void)
  30 {
  31   int failures = 0;
  32   struct ifaddrs *ifaces, *ifa;
  33
  34   if (getifaddrs (&ifaces) < 0)
  35     {
  36       if (errno != ENOSYS)
  37         {
  38           printf ("Couldn't get any interfaces: %s.\n", strerror (errno));
  39           exit (1);
  40         }
  41       /* The function is simply not implemented.  */
  42       exit (0);
  43     }
  44
  45   puts ("\
  46 Name           Flags   Address         Netmask         Broadcast/Destination");
  47
  48   for (ifa = ifaces; ifa != NULL; ifa = ifa->ifa_next)
  49     {
  50       char abuf[64], mbuf[64], dbuf[64];
  51       inline const char *addr_string (struct sockaddr *sa, char *buf)
  52         {
  53           if (sa == NULL)
  54             return "<none>";
  55
  56           switch (sa->sa_family)
  57             {
  58             case AF_INET:
  59               return inet_ntop (AF_INET,
  60                                 &((struct sockaddr_in *) sa)->sin_addr,
  61                                 buf, sizeof abuf);
  62             case AF_INET6:
  63               return inet_ntop (AF_INET6,
  64                                 &((struct sockaddr_in6 *) sa)->sin6_addr,
  65                                 buf, sizeof abuf);
  66 #ifdef AF_LINK
  67             case AF_LINK:
  68               return "<link>";
  69 #endif
  70             case AF_UNSPEC:
  71               return "---";
  72             default:
  73               ++failures;
  74               printf ("sa_family=%d %08x\n", sa->sa_family,
  75                       *(int*)&((struct sockaddr_in *) sa)->sin_addr.s_addr);
  76               return "<unexpected sockaddr family>";
  77             }
  78         }
  79       printf ("%-15s%#.4x  %-15s %-15s %-15s\n",
  80               ifa->ifa_name, ifa->ifa_flags,
  81               addr_string (ifa->ifa_addr, abuf),
  82               addr_string (ifa->ifa_netmask, mbuf),
  83               addr_string (ifa->ifa_broadaddr, dbuf));
  84     }
  85
  86   freeifaddrs (ifaces);
  87
  88   return failures ? 1 : 0;
  89 }