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/* Copyright (C) 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005
Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
Reworked Dec 2002 by Erik Andersen <andersen@codepoet.org>
*/
#define strndup __strndup
#define __FORCE_GLIBC
#include <features.h>
#define __USE_GNU
#include <string.h>
#include <alloca.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <libc-internal.h>
extern int __opensock(void) attribute_hidden;
unsigned int
if_nametoindex(const char* ifname)
{
#ifndef SIOCGIFINDEX
__set_errno (ENOSYS);
return 0;
#else
struct ifreq ifr;
int fd = __opensock();
if (fd < 0)
return 0;
__strncpy (ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
if (__ioctl (fd, SIOCGIFINDEX, &ifr) < 0)
{
int saved_errno = errno;
__close(fd);
if (saved_errno == EINVAL)
__set_errno(ENOSYS);
return 0;
}
__close(fd);
return ifr.ifr_ifindex;
#endif
}
hidden_strong_alias(if_nametoindex,__if_nametoindex)
void
if_freenameindex (struct if_nameindex *ifn)
{
struct if_nameindex *ptr = ifn;
while (ptr->if_name || ptr->if_index)
{
free (ptr->if_name);
++ptr;
}
free (ifn);
}
struct if_nameindex *
if_nameindex (void)
{
#ifndef SIOCGIFINDEX
__set_errno (ENOSYS);
return NULL;
#else
int fd = __opensock ();
struct ifconf ifc;
unsigned int nifs, i;
int rq_len;
struct if_nameindex *idx = NULL;
# define RQ_IFS 4
if (fd < 0)
return NULL;
ifc.ifc_buf = NULL;
/* Guess on the correct buffer size... */
rq_len = RQ_IFS * sizeof (struct ifreq);
/* Read all the interfaces out of the kernel. */
/* Note: alloca's in this loop are diff from glibc because it's smaller */
do
{
ifc.ifc_buf = extend_alloca (ifc.ifc_buf, rq_len, 2 * rq_len);
ifc.ifc_len = rq_len;
if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0)
{
__close (fd);
return NULL;
}
}
while (ifc.ifc_len == rq_len);
nifs = ifc.ifc_len / sizeof(struct ifreq);
idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
if (idx == NULL)
{
__close(fd);
__set_errno(ENOBUFS);
return NULL;
}
for (i = 0; i < nifs; ++i)
{
struct ifreq *ifr = &ifc.ifc_req[i];
idx[i].if_name = __strdup (ifr->ifr_name);
if (idx[i].if_name == NULL
|| __ioctl (fd, SIOCGIFINDEX, ifr) < 0)
{
int saved_errno = errno;
unsigned int j;
for (j = 0; j < i; ++j)
free (idx[j].if_name);
free(idx);
__close(fd);
if (saved_errno == EINVAL)
saved_errno = ENOSYS;
else if (saved_errno == ENOMEM)
saved_errno = ENOBUFS;
__set_errno (saved_errno);
return NULL;
}
idx[i].if_index = ifr->ifr_ifindex;
}
idx[i].if_index = 0;
idx[i].if_name = NULL;
__close(fd);
return idx;
#endif
}
char *
if_indextoname (unsigned int ifindex, char *ifname)
{
#if !defined SIOCGIFINDEX
__set_errno (ENOSYS);
return NULL;
#else
# ifdef SIOCGIFNAME
/* Use ioctl to avoid searching the list. */
struct ifreq ifr;
int fd;
fd = __opensock ();
if (fd < 0)
return NULL;
ifr.ifr_ifindex = ifindex;
if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
{
int serrno = errno;
__close (fd);
if (serrno == ENODEV)
/* POSIX requires ENXIO. */
serrno = ENXIO;
__set_errno (serrno);
return NULL;
}
__close (fd);
return __strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
# else
struct if_nameindex *idx;
struct if_nameindex *p;
char *result = NULL;
idx = if_nameindex();
if (idx != NULL)
{
for (p = idx; p->if_index || p->if_name; ++p)
if (p->if_index == ifindex)
{
result = __strncpy (ifname, p->if_name, IFNAMSIZ);
break;
}
if_freenameindex (idx);
if (result == NULL)
__set_errno (ENXIO);
}
return result;
# endif
#endif
}
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