add bridge master device support

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
diff --git a/ip/iplink_bridge.c b/ip/iplink_bridge.c
new file mode 100644
index 0000000..0cea7d1
--- /dev/null
+++ b/ip/iplink_bridge.c
@@ -0,0 +1,93 @@
+/*
+ * iplink_bridge.c	Bridge device support
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Jiri Pirko <jiri@resnulli.us>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/if_link.h>
+
+#include "utils.h"
+#include "ip_common.h"
+
+static void explain(void)
+{
+	fprintf(stderr,
+		"Usage: ... bridge [ forward_delay FORWARD_DELAY ]\n"
+		"                  [ hello_time HELLO_TIME ]\n"
+		"                  [ max_age MAX_AGE ]\n"
+	);
+}
+
+static int bridge_parse_opt(struct link_util *lu, int argc, char **argv,
+			    struct nlmsghdr *n)
+{
+	__u32 val;
+
+	while (argc > 0) {
+		if (matches(*argv, "forward_delay") == 0) {
+			NEXT_ARG();
+			if (get_u32(&val, *argv, 0)) {
+				invarg("invalid forward_delay", *argv);
+				return -1;
+			}
+			addattr32(n, 1024, IFLA_BR_FORWARD_DELAY, val);
+		} else if (matches(*argv, "hello_time") == 0) {
+			NEXT_ARG();
+			if (get_u32(&val, *argv, 0)) {
+				invarg("invalid hello_time", *argv);
+				return -1;
+			}
+			addattr32(n, 1024, IFLA_BR_HELLO_TIME, val);
+		} else if (matches(*argv, "max_age") == 0) {
+			NEXT_ARG();
+			if (get_u32(&val, *argv, 0)) {
+				invarg("invalid max_age", *argv);
+				return -1;
+			}
+			addattr32(n, 1024, IFLA_BR_MAX_AGE, val);
+		} else if (matches(*argv, "help") == 0) {
+			explain();
+			return -1;
+		} else {
+			fprintf(stderr, "bridge: unknown command \"%s\"?\n", *argv);
+			explain();
+			return -1;
+		}
+		argc--, argv++;
+	}
+
+	return 0;
+}
+
+static void bridge_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
+{
+	if (!tb)
+		return;
+
+	if (tb[IFLA_BR_FORWARD_DELAY])
+		fprintf(f, "forward_delay %u ",
+			rta_getattr_u32(tb[IFLA_BR_FORWARD_DELAY]));
+
+	if (tb[IFLA_BR_HELLO_TIME])
+		fprintf(f, "hello_time %u ",
+			rta_getattr_u32(tb[IFLA_BR_HELLO_TIME]));
+
+	if (tb[IFLA_BR_MAX_AGE])
+		fprintf(f, "max_age %u ",
+			rta_getattr_u32(tb[IFLA_BR_MAX_AGE]));
+}
+
+struct link_util bridge_link_util = {
+	.id		= "bridge",
+	.maxattr	= IFLA_BR_MAX,
+	.parse_opt	= bridge_parse_opt,
+	.print_opt	= bridge_print_opt,
+};