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/* $Id$ */
/*
 * Copyright (c) 2004 demon <demon@vhost.dyndns.org>
 *
 * 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.
 */

#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <err.h>
#include <string.h>
#include <unistd.h>
#include "ifaddr.h"

int
if_ntoa(char *if_name, char **if_addr)
{
	struct ifreq ifr;
	struct sockaddr_in sin;
	int fd;

	memset(&ifr, '\0', sizeof(ifr));

	strncpy(ifr.ifr_name, if_name, sizeof(ifr.ifr_name) - 1);

	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
		err(1, "socket()");

	if (ioctl(fd, SIOCGIFADDR, &ifr) < 0) {
		close(fd);
		err(1, "ioctl()");
	}

	memcpy(&sin, &(ifr.ifr_addr), sizeof(sin));

	*if_addr = inet_ntoa(sin.sin_addr);

	close(fd);
	return 0;
}