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/* $Id: myaddrs.C,v 1.8 2001/07/26 23:05:05 dm Exp $ */
/*
*
* Copyright (C) 1998 David Mazieres (dm@uun.org)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
*/
#include "amisc.h"
#include "qhash.h"
#include <net/if.h>
#ifdef HAVE_SYS_SOCKIO_H
#include <sys/sockio.h>
#endif /* HAVE_SYS_SOCKIO_H */
#define MAXCONFBUF 0x10000
bool
myipaddrs (vec<in_addr> *res)
{
struct ifconf ifc;
char *p, *e;
int s;
if ((s = socket (AF_INET, SOCK_DGRAM, 0)) < 0) {
warn ("socket: %m\n");
return false;
}
errno = 0;
ifc.ifc_len = MAXCONFBUF;
ifc.ifc_buf = NULL;
for (u_int len = 512;;) {
ifc.ifc_len = len;
xfree (ifc.ifc_buf);
ifc.ifc_buf = (char *) xmalloc (ifc.ifc_len);
if (ioctl (s, SIOCGIFCONF, &ifc) < 0) {
warn ("SIOCGIFCONF: %m\n");
close (s);
xfree (ifc.ifc_buf);
return false;
}
/* The +64 is for large addresses (e.g., IPv6), in which sa_len
* may be greater than the struct sockaddr inside ifreq. */
if (ifc.ifc_len + sizeof (struct ifreq) + 64 < len)
break;
len *= 2;
if (len > MAXCONFBUF) {
warn ("SIOCGIFCONF: buffer too large\n");
close (s);
xfree (ifc.ifc_buf);
return false;
}
}
res->clear ();
bhash<in_addr> addrs;
p = ifc.ifc_buf;
e = p + ifc.ifc_len;
while (p < e) {
struct ifreq *ifrp = (struct ifreq *) p;
struct ifreq ifr = *ifrp;
#ifndef HAVE_SA_LEN
p += sizeof (ifr);
#else /* !HAVE_SA_LEN */
p += sizeof (ifrp->ifr_name)
+ max (sizeof (ifrp->ifr_addr), (size_t) ifrp->ifr_addr.sa_len);
#endif /* !HAVE_SA_LEN */
if (ifrp->ifr_addr.sa_family != AF_INET)
continue;
if (ioctl (s, SIOCGIFFLAGS, &ifr) < 0) {
warn ("SIOCGIFFLAGS (%.*s): %m\n", (int) sizeof (ifr.ifr_name),
ifr.ifr_name);
continue;
}
in_addr a = ((struct sockaddr_in *) &ifrp->ifr_addr)->sin_addr;
if ((ifr.ifr_flags & IFF_UP) && !addrs[a]) {
addrs.insert (a);
res->push_back (a);
}
}
xfree (ifc.ifc_buf);
close (s);
return true;
}
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