usr/src/lib/libc/port/nsl/can_use_af.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22
  23 /*
  24  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27
  28 #pragma ident   "%Z%%M% %I%     %E% SMI"
  29
  30 #include "mt.h"
  31 #include "rpc_mt.h"
  32 #include <stdio.h>
  33 #include <fcntl.h>
  34 #include <sys/types.h>
  35 #include <sys/socket.h>
  36 #include <unistd.h>
  37 #include <net/if.h>
  38 #include <sys/sockio.h>
  39
  40 /*
  41  * Determine if we have a configured interface for the specified address
  42  * family.
  43  */
  44 int
  45 __can_use_af(sa_family_t af)
  46 {
  47         struct lifnum   lifn;
  48         int             fd;
  49
  50         if ((fd =  open("/dev/udp", O_RDONLY)) < 0)
  51                 return (0);
  52         lifn.lifn_family = af;
  53         /* XXX Remove this after fixing 6204567 */
  54         /* CONSTCOND */
  55         lifn.lifn_flags = IFF_UP & !(IFF_NOXMIT | IFF_DEPRECATED);
  56         if (ioctl(fd, SIOCGLIFNUM, &lifn, sizeof (lifn)) < 0)
  57                 lifn.lifn_count = 0;
  58
  59         (void) close(fd);
  60         return (lifn.lifn_count);
  61 }