components/ip.c
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/* See LICENSE file for copyright and license details. */
#include <errno.h>
#include <ifaddrs.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#if defined(__OpenBSD__)
#include <sys/types.h>
#include <sys/socket.h>
#endif
#include "../util.h"
static const char *
ip(const char *iface, unsigned short sa_family)
{
struct ifaddrs *ifaddr, *ifa;
int s;
char host[NI_MAXHOST];
if (getifaddrs(&ifaddr) < 0) {
warn("getifaddrs:");
return NULL;
}
for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
if (!ifa->ifa_addr) {
continue;
}
s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in6),
host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
if (!strcmp(ifa->ifa_name, iface) &&
(ifa->ifa_addr->sa_family == sa_family)) {
if (s != 0) {
warn("getnameinfo: %s", gai_strerror(s));
return NULL;
}
return bprintf("%s", host);
}
}
freeifaddrs(ifaddr);
return NULL;
}
const char *
ipv4(const char *iface)
{
return ip(iface, AF_INET);
}
const char *
ipv6(const char *iface)
{
return ip(iface, AF_INET6);
}