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/* Copyright (C) 1997 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <net/if.h>
#define IF_INET6_FILENAME "/proc/net/if_inet6"
/* /proc/net/if_inet6 contains lines that look like this:
*
* fe8000000000000000000000836fc168 0b 00 20 80 sit7
*
* | | | | | |
* address --' | | | | |
* index --------' | | | |
* prefix length ---' | | |
* scope --------------' | |
* flags -----------------' |
* name -------------------------'
*
*/
static int get_one_interface(FILE *fd, char *interface, int iflen, unsigned int *index)
{
char buffer[80];
static char seps[] = " \012";
char *c = buffer;
char *sp;
if (!fgets(buffer, 80, fd))
return 1;
if (strtok_r(buffer, seps, &sp) == NULL) return 1;
if (c = strtok_r(NULL, seps, &sp), c == NULL) return 1;
*index = strtoul(c, NULL, 16);
if (strtok_r(NULL, seps, &sp) == NULL) return 1;
if (strtok_r(NULL, seps, &sp) == NULL) return 1;
if (strtok_r(NULL, seps, &sp) == NULL) return 1;
if (c = strtok_r(NULL, seps, &sp), c == NULL) return 1;
strncpy(interface, c, iflen);
return 0;
}
unsigned int if_nametoindex(const char *ifname)
{
FILE *fd = fopen(IF_INET6_FILENAME, "r");
char this_ifname[IFNAMSIZ];
unsigned int this_index;
if (!fd) return 0;
while (get_one_interface(fd, this_ifname, IFNAMSIZ, &this_index) == 0) {
if (!strcmp(this_ifname, ifname)) {
fclose(fd);
return this_index;
}
}
fclose(fd);
return 0;
}
char *if_indextoname(unsigned int ifindex, char *ifname)
{
FILE *fd = fopen(IF_INET6_FILENAME, "r");
unsigned int this_index;
if (!fd) return NULL;
while (get_one_interface(fd, ifname, IFNAMSIZ, &this_index) == 0) {
if (this_index == ifindex) {
fclose(fd);
return ifname;
}
}
fclose(fd);
return NULL;
}
void if_freenameindex(struct if_nameindex *ifn)
{
struct if_nameindex *ptr = ifn;
while (ptr->if_name || ptr->if_index)
{
if (ptr->if_name)
free(ptr->if_name);
ptr++;
}
free(ifn);
}
struct if_nameindex *if_nameindex(void)
{
FILE *fd = fopen(IF_INET6_FILENAME, "r");
struct if_nameindex *ifn = NULL;
int nifs = 0;
if (!fd) return NULL;
do
{
struct if_nameindex *newifn;
nifs++;
newifn = realloc(ifn, nifs*sizeof(struct if_nameindex));
if (!newifn)
{
/* We ran out of memory. */
if (--nifs)
{
free(ifn[nifs-1].if_name);
ifn[nifs-1].if_name = 0;
ifn[nifs-1].if_index = 0;
if_freenameindex(ifn);
}
return NULL;
}
ifn = newifn;
ifn[nifs-1].if_index = 0;
ifn[nifs-1].if_name = malloc(IFNAMSIZ);
if (ifn[nifs-1].if_name == NULL)
{
if_freenameindex(ifn);
return NULL;
}
}
while (get_one_interface(fd, ifn[nifs-1].if_name, IFNAMSIZ,
&ifn[nifs-1].if_index) == 0);
free(ifn[nifs-1].if_name);
ifn[nifs-1].if_name = NULL;
fclose(fd);
return ifn;
}
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