upd5

if.c.v

@@ -0,0 +1,64 @@
+module netio
+
+import os
+
+#include <net/if.h>
+
+struct C.if_nameindex {
+	if_index u32
+	if_name  &char
+}
+
+fn C.if_nametoindex(&char) u32
+fn C.if_indextoname(u32, &char) &char
+fn C.if_nameindex() &C.if_nameindex
+fn C.if_freenameindex(voidptr)
+
+// name_to_index translates the network interface name to index.
+pub fn name_to_index(name string) !u32 {
+	index := C.if_nametoindex(&char(name.str))
+	if index == 0 {
+		return error('${@FN}: no index for `${name}`')
+	}
+	return index
+}
+
+// index_to_name translates the network interface index to name e.g. 'eth0'.
+pub fn index_to_name(index u32) !string {
+	name := []u8{len: C.IF_NAMESIZE}
+	ifname := C.if_indextoname(index, name.data)
+	if isnil(ifname) {
+		return os.last_error()
+	}
+	return unsafe { cstring_to_vstring(ifname) }
+}
+
+pub struct NetworkInterface {
+	index u32
+	name  string
+}
+
+// interfaces returns an array with names and indexes of all network interfaces in system.
+pub fn interfaces() ![]NetworkInterface {
+	ifaces := C.if_nameindex()
+	if isnil(ifaces) {
+		return os.last_error()
+	}
+	defer {
+		C.if_freenameindex(ifaces)
+	}
+	mut result := []NetworkInterface{}
+	mut i := 0
+	for {
+		iface := unsafe { ifaces[i] }
+		i++
+		if iface.if_index == 0 && isnil(iface.if_name) {
+			break
+		}
+		result << NetworkInterface{
+			index: iface.if_index
+			name:  unsafe { cstring_to_vstring(iface.if_name) }
+		}
+	}
+	return result
+}