Initial fork from https://git.suckless.org/slstatus

Changes to be committed:
    new file:   LICENSE
    new file:   Makefile
    new file:   README
    new file:   arg.h
    new file:   components/battery.c
    new file:   components/cat.c
    new file:   components/cpu.c
    new file:   components/datetime.c
    new file:   components/disk.c
    new file:   components/entropy.c
    new file:   components/hostname.c
    new file:   components/ip.c
    new file:   components/kernel_release.c
    new file:   components/keyboard_indicators.c
    new file:   components/keymap.c
    new file:   components/load_avg.c
    new file:   components/netspeeds.c
    new file:   components/num_files.c
    new file:   components/ram.c
    new file:   components/run_command.c
    new file:   components/swap.c
    new file:   components/temperature.c
    new file:   components/uptime.c
    new file:   components/user.c
    new file:   components/volume.c
    new file:   components/wifi.c
    new file:   config.def.h
    new file:   config.mk
    new file:   slstatus.1
    new file:   slstatus.c
    new file:   slstatus.h
    new file:   util.c
    new file:   util.h

1 files changed, 61 insertions, 0 deletions

diff --git a/components/ip.c b/components/ip.c
new file mode 100644
index 0000000..9476549
--- /dev/null
+++ b/components/ip.c
@@ -0,0 +1,61 @@
+/* See LICENSE file for copyright and license details. */
+#include <ifaddrs.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <string.h>
+#if defined(__OpenBSD__)
+	#include <sys/socket.h>
+	#include <sys/types.h>
+#elif defined(__FreeBSD__)
+	#include <netinet/in.h>
+	#include <sys/socket.h>
+#endif
+
+#include "../slstatus.h"
+#include "../util.h"
+
+static const char *
+ip(const char *interface, 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, interface) &&
+		    (ifa->ifa_addr->sa_family == sa_family)) {
+			freeifaddrs(ifaddr);
+			if (s != 0) {
+				warn("getnameinfo: %s", gai_strerror(s));
+				return NULL;
+			}
+			return bprintf("%s", host);
+		}
+	}
+
+	freeifaddrs(ifaddr);
+
+	return NULL;
+}
+
+const char *
+ipv4(const char *interface)
+{
+	return ip(interface, AF_INET);
+}
+
+const char *
+ipv6(const char *interface)
+{
+	return ip(interface, AF_INET6);
+}