busybox/networking/libiproute/ll_map.c
Ron Yorston 8814431aca libiproute: use if_nametoindex
Saves 87 bytes.  Assuming, of course, all platforms have it.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-24 22:04:36 +02:00

180 lines
3.5 KiB
C

/* vi: set sw=4 ts=4: */
/*
* 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 of the License, or (at your option) any later version.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*/
#include <net/if.h> /* struct ifreq and co. */
#include "libbb.h"
#include "libnetlink.h"
#include "ll_map.h"
struct idxmap {
struct idxmap *next;
int index;
int type;
int alen;
unsigned flags;
unsigned char addr[8];
char name[16];
};
static struct idxmap **idxmap; /* treat as *idxmap[16] */
static struct idxmap *find_by_index(int idx)
{
struct idxmap *im;
if (idxmap)
for (im = idxmap[idx & 0xF]; im; im = im->next)
if (im->index == idx)
return im;
return NULL;
}
int FAST_FUNC ll_remember_index(const struct sockaddr_nl *who UNUSED_PARAM,
struct nlmsghdr *n,
void *arg UNUSED_PARAM)
{
int h;
struct ifinfomsg *ifi = NLMSG_DATA(n);
struct idxmap *im, **imp;
struct rtattr *tb[IFLA_MAX+1];
if (n->nlmsg_type != RTM_NEWLINK)
return 0;
if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
return -1;
memset(tb, 0, sizeof(tb));
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
if (tb[IFLA_IFNAME] == NULL)
return 0;
if (!idxmap)
idxmap = xzalloc(sizeof(idxmap[0]) * 16);
h = ifi->ifi_index & 0xF;
for (imp = &idxmap[h]; (im = *imp) != NULL; imp = &im->next)
if (im->index == ifi->ifi_index)
goto found;
im = xmalloc(sizeof(*im));
im->next = *imp;
im->index = ifi->ifi_index;
*imp = im;
found:
im->type = ifi->ifi_type;
im->flags = ifi->ifi_flags;
if (tb[IFLA_ADDRESS]) {
int alen;
im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]);
if (alen > (int)sizeof(im->addr))
alen = sizeof(im->addr);
memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen);
} else {
im->alen = 0;
memset(im->addr, 0, sizeof(im->addr));
}
strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME]));
return 0;
}
static
const char FAST_FUNC *ll_idx_n2a(int idx/*, char *buf*/)
{
struct idxmap *im;
if (idx == 0)
return "*";
im = find_by_index(idx);
if (im)
return im->name;
//snprintf(buf, 16, "if%d", idx);
//return buf;
return auto_string(xasprintf("if%d", idx));
}
const char FAST_FUNC *ll_index_to_name(int idx)
{
//static char nbuf[16];
return ll_idx_n2a(idx/*, nbuf*/);
}
#ifdef UNUSED
int ll_index_to_type(int idx)
{
struct idxmap *im;
if (idx == 0)
return -1;
im = find_by_index(idx);
if (im)
return im->type;
return -1;
}
#endif
unsigned FAST_FUNC ll_index_to_flags(int idx)
{
struct idxmap *im;
if (idx == 0)
return 0;
im = find_by_index(idx);
if (im)
return im->flags;
return 0;
}
int FAST_FUNC xll_name_to_index(const char *name)
{
int ret = 0;
/* caching is not warranted - no users which repeatedly call it */
#ifdef UNUSED
static char ncache[16];
static int icache;
struct idxmap *im;
int i;
if (name == NULL)
goto out;
if (icache && strcmp(name, ncache) == 0) {
ret = icache;
goto out;
}
if (idxmap) {
for (i = 0; i < 16; i++) {
for (im = idxmap[i]; im; im = im->next) {
if (strcmp(im->name, name) == 0) {
icache = im->index;
strcpy(ncache, name);
ret = im->index;
goto out;
}
}
}
}
#endif
ret = if_nametoindex(name);
/* out:*/
if (ret <= 0)
bb_error_msg_and_die("can't find device '%s'", name);
return ret;
}
int FAST_FUNC ll_init_map(struct rtnl_handle *rth)
{
xrtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK);
xrtnl_dump_filter(rth, ll_remember_index, NULL);
return 0;
}