text: /*
   * ll_map.c
   *
   *		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 <stdio.h>
  #include <string.h>
  #include <stdlib.h>
  #include <netinet/in.h>
  
  #include "libnetlink.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[16];
  
  int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
  {
  	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;
  
  	h = ifi->ifi_index&0xF;
  
  	for (imp=&idxmap[h]; (im=*imp)!=NULL; imp = &im->next)
  		if (im->index == ifi->ifi_index)
  			break;
  
  	if (im == NULL) {
  		im = malloc(sizeof(*im));
  		if (im == NULL)
  			return 0;
  		im->next = *imp;
  		im->index = ifi->ifi_index;
  		*imp = im;
  	}
  
  	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 > 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;
  }
  
  const char *ll_idx_n2a(int idx, char *buf)
  {
  	struct idxmap *im;
  
  	if (idx == 0)
  		return "*";
  	for (im = idxmap[idx&0xF]; im; im = im->next)
  		if (im->index == idx)
  			return im->name;
  	snprintf(buf, 16, "if%d", idx);
  	return buf;
  }
  
  
  const char *ll_index_to_name(int idx)
  {
  	static char nbuf[16];
  
  	return ll_idx_n2a(idx, nbuf);
  }
  
  int ll_index_to_type(int idx)
  {
  	struct idxmap *im;
  
  	if (idx == 0)
  		return -1;
  	for (im = idxmap[idx&0xF]; im; im = im->next)
  		if (im->index == idx)
  			return im->type;
  	return -1;
  }
  
  unsigned ll_index_to_flags(int idx)
  {
  	struct idxmap *im;
  
  	if (idx == 0)
  		return 0;
  
  	for (im = idxmap[idx&0xF]; im; im = im->next)
  		if (im->index == idx)
  			return im->flags;
  	return 0;
  }
  
  int ll_name_to_index(char *name)
  {
  	static char ncache[16];
  	static int icache;
  	struct idxmap *im;
  	int i;
  
  	if (name == NULL)
  		return 0;
  	if (icache && strcmp(name, ncache) == 0)
  		return icache;
  	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);
  				return im->index;
  			}
  		}
  	}
  	return 0;
  }
  
  int ll_init_map(struct rtnl_handle *rth)
  {
  	if (rtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK) < 0) {
  		perror("Cannot send dump request");
  		exit(1);
  	}
  
  	if (rtnl_dump_filter(rth, ll_remember_index, &idxmap, NULL, NULL) < 0) {
  		fprintf(stderr, "Dump terminated\n");
  		exit(1);
  	}
  	return 0;
  }
  