RouteUpdate gains Flags field

It allows to distinguish between a new created route or a replaced one.

Signed-off-by: Maxime Soulé <[email protected]>

route.go

@@ -154,8 +154,15 @@ type flagString struct {
 }
 
 // RouteUpdate is sent when a route changes - type is RTM_NEWROUTE or RTM_DELROUTE
+
+// Flags is only non-zero for RTM_NEWROUTE, the following flags can be set:
+//   - unix.NLM_F_REPLACE - Replace existing matching config object with this request
+//   - unix.NLM_F_EXCL - Don't replace the config object if it already exists
+//   - unix.NLM_F_CREATE - Create config object if it doesn't already exist
+//   - unix.NLM_F_APPEND - Add to the end of the object list
 type RouteUpdate struct {
-	Type uint16
+	Type  uint16
+	Flags uint16
 	Route
 }
 

route_linux.go

@@ -1561,7 +1561,11 @@ func routeSubscribeAt(newNs, curNs netns.NsHandle, ch chan<- RouteUpdate, done <
 					}
 					continue
 				}
-				ch <- RouteUpdate{Type: m.Header.Type, Route: route}
+				ch <- RouteUpdate{
+					Type:  m.Header.Type,
+					Flags: m.Header.Flags & (unix.NLM_F_REPLACE | unix.NLM_F_EXCL | unix.NLM_F_CREATE | unix.NLM_F_APPEND),
+					Route: route,
+				}
 			}
 		}
 	}()

route_test.go

@@ -477,13 +477,14 @@ func TestRouteAddIncomplete(t *testing.T) {
 	}
 }
 
-// expectNeighUpdate returns whether the expected updated is received within one minute.
-func expectRouteUpdate(ch <-chan RouteUpdate, t uint16, dst net.IP) bool {
+// expectRouteUpdate returns whether the expected updated is received within one minute.
+func expectRouteUpdate(ch <-chan RouteUpdate, t, f uint16, dst net.IP) bool {
 	for {
 		timeout := time.After(time.Minute)
 		select {
 		case update := <-ch:
 			if update.Type == t &&
+				update.Flags == f &&
 				update.Route.Dst != nil &&
 				update.Route.Dst.IP.Equal(dst) {
 				return true
@@ -528,13 +529,13 @@ func TestRouteSubscribe(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, unix.NLM_F_EXCL|unix.NLM_F_CREATE, dst.IP) {
 		t.Fatal("Add update not received as expected")
 	}
 	if err := RouteDel(&route); err != nil {
 		t.Fatal(err)
 	}
-	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, 0, dst.IP) {
 		t.Fatal("Del update not received as expected")
 	}
 }
@@ -583,7 +584,7 @@ func TestRouteSubscribeWithOptions(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, unix.NLM_F_EXCL|unix.NLM_F_CREATE, dst.IP) {
 		t.Fatal("Add update not received as expected")
 	}
 }
@@ -635,13 +636,13 @@ func TestRouteSubscribeAt(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, unix.NLM_F_EXCL|unix.NLM_F_CREATE, dst.IP) {
 		t.Fatal("Add update not received as expected")
 	}
 	if err := nh.RouteDel(&route); err != nil {
 		t.Fatal(err)
 	}
-	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, 0, dst.IP) {
 		t.Fatal("Del update not received as expected")
 	}
 }
@@ -696,7 +697,7 @@ func TestRouteSubscribeListExisting(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, dst10.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, 0, dst10.IP) {
 		t.Fatal("Existing add update not received as expected")
 	}
 
@@ -711,19 +712,19 @@ func TestRouteSubscribeListExisting(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_NEWROUTE, unix.NLM_F_EXCL|unix.NLM_F_CREATE, dst.IP) {
 		t.Fatal("Add update not received as expected")
 	}
 	if err := nh.RouteDel(&route); err != nil {
 		t.Fatal(err)
 	}
-	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, dst.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, 0, dst.IP) {
 		t.Fatal("Del update not received as expected")
 	}
 	if err := nh.RouteDel(&route10); err != nil {
 		t.Fatal(err)
 	}
-	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, dst10.IP) {
+	if !expectRouteUpdate(ch, unix.RTM_DELROUTE, 0, dst10.IP) {
 		t.Fatal("Del update not received as expected")
 	}
 }