sortix-mirror/libc/net/if/if_nametoindex.c

44 lines
1.4 KiB
C

/*
* Copyright (c) 2016 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* net/if/if_nametoindex.c
* Get index of network interface by name.
*/
#include <errno.h>
#include <net/if.h>
#include <stdlib.h>
#include <string.h>
// TODO: This is better done with a dedicated system call.
// TODO: Or at least the name can be looked up directly in /dev.
unsigned int if_nametoindex(const char* name)
{
struct if_nameindex* ifs = if_nameindex();
if ( !ifs )
return NULL;
for ( size_t i = 0; ifs[i].if_index; i++ )
{
if ( !strcmp(ifs[i].if_name, name) )
{
unsigned int result = ifs[i].if_index;
if_freenameindex(ifs);
return result;
}
}
if_freenameindex(ifs);
return 0;
}