minidlna/getifaddr.c
2008-10-23 17:30:45 +00:00

56 lines
1.1 KiB
C

/* $Id$ */
/* MiniUPnP project
* http://miniupnp.free.fr/ or http://miniupnp.tuxfamily.org/
* (c) 2006 Thomas Bernard
* This software is subject to the conditions detailed
* in the LICENCE file provided within the distribution */
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#if defined(sun)
#include <sys/sockio.h>
#endif
#include "getifaddr.h"
int
getifaddr(const char * ifname, char * buf, int len)
{
/* SIOCGIFADDR struct ifreq * */
int s;
struct ifreq ifr;
int ifrlen;
struct sockaddr_in * addr;
ifrlen = sizeof(ifr);
s = socket(PF_INET, SOCK_DGRAM, 0);
if(s < 0)
{
syslog(LOG_ERR, "socket(PF_INET, SOCK_DGRAM): %m");
return -1;
}
strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if(ioctl(s, SIOCGIFADDR, &ifr, &ifrlen) < 0)
{
syslog(LOG_ERR, "ioctl(s, SIOCGIFADDR, ...): %m");
close(s);
return -1;
}
addr = (struct sockaddr_in *)&ifr.ifr_addr;
if(!inet_ntop(AF_INET, &addr->sin_addr, buf, len))
{
syslog(LOG_ERR, "inet_ntop(): %m");
close(s);
return -1;
}
close(s);
return 0;
}