From a609b5e8f39b132ff72476761add46d263c4147f Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Mon, 19 Mar 2012 23:26:44 +0100
Subject: [PATCH] add support for updating route metrics

---
 interface-ip.c |  7 +++++--
 interface-ip.h |  2 +-
 interface.c    | 18 +++++++++++++++---
 interface.h    |  2 ++
 4 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/interface-ip.c b/interface-ip.c
index 56f3c0c..8c46168 100644
--- a/interface-ip.c
+++ b/interface-ip.c
@@ -377,9 +377,12 @@ void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
 		if (route->enabled == _enabled)
 			continue;
 
-		if (_enabled)
+		if (_enabled) {
+			if (!(route->flags & DEVROUTE_METRIC))
+				route->metric = ip->iface->metric;
+
 			system_add_route(dev, route);
-		else
+		} else
 			system_del_route(dev, route);
 		route->enabled = _enabled;
 	}
diff --git a/interface-ip.h b/interface-ip.h
index 68bfdf6..df5545d 100644
--- a/interface-ip.h
+++ b/interface-ip.h
@@ -76,6 +76,6 @@ void interface_ip_update_start(struct interface_ip_settings *ip);
 void interface_ip_update_complete(struct interface_ip_settings *ip);
 void interface_ip_flush(struct interface_ip_settings *ip);
 void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled);
-
+void interface_ip_update_metric(struct interface_ip_settings *ip, int metric);
 
 #endif
diff --git a/interface.c b/interface.c
index 4ad89f5..f281a9b 100644
--- a/interface.c
+++ b/interface.c
@@ -18,6 +18,7 @@ enum {
 	IFACE_ATTR_PROTO,
 	IFACE_ATTR_AUTO,
 	IFACE_ATTR_DEFAULTROUTE,
+	IFACE_ATTR_METRIC,
 	IFACE_ATTR_MAX
 };
 
@@ -26,6 +27,7 @@ static const struct blobmsg_policy iface_attrs[IFACE_ATTR_MAX] = {
 	[IFACE_ATTR_IFNAME] = { .name = "ifname", .type = BLOBMSG_TYPE_STRING },
 	[IFACE_ATTR_AUTO] = { .name = "auto", .type = BLOBMSG_TYPE_BOOL },
 	[IFACE_ATTR_DEFAULTROUTE] = { .name = "defaultroute", .type = BLOBMSG_TYPE_BOOL },
+	[IFACE_ATTR_METRIC] = { .name = "metric", .type = BLOBMSG_TYPE_INT32 },
 };
 
 const struct config_param_list interface_attr_list = {
@@ -516,11 +518,21 @@ interface_change_config(struct interface *if_old, struct interface *if_new)
 		goto reload;
 	}
 
-	if (if_old->proto_ip.no_defaultroute != if_new->proto_ip.no_defaultroute) {
-		if_old->proto_ip.no_defaultroute = if_new->proto_ip.no_defaultroute;
-		interface_ip_set_enabled(&if_old->proto_ip, if_old->proto_ip.enabled);
+#define UPDATE(field) ({						\
+		bool __changed = (if_old->field != if_new->field);	\
+		if_old->field = if_new->field;				\
+		__changed;						\
+	})
+
+	if (UPDATE(metric) || UPDATE(proto_ip.no_defaultroute)) {
+		interface_ip_set_enabled(&if_old->config_ip, false);
+		interface_ip_set_enabled(&if_old->config_ip, if_new->config_ip.enabled);
+		interface_ip_set_enabled(&if_old->proto_ip, false);
+		interface_ip_set_enabled(&if_old->proto_ip, if_new->proto_ip.enabled);
 	}
 
+#undef UPDATE
+
 	goto out;
 
 reload:
diff --git a/interface.h b/interface.h
index 750c0f2..f0b26f5 100644
--- a/interface.h
+++ b/interface.h
@@ -87,6 +87,8 @@ struct interface {
 	struct interface_ip_settings proto_ip;
 	struct interface_ip_settings config_ip;
 
+	int metric;
+
 	/* errors/warnings while trying to bring up the interface */
 	struct list_head errors;
 
-- 
2.11.0