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- start list of linux_only plugins; ignore them when testing on Windows
- Isolate linux-only code by filename suffix
- Remove stub (NotImplemented) functions
- other misc. fixes for Windows compatibility

pkg/ip/addr_linux.go

@@ -0,0 +1,68 @@
+// Copyright 2017 CNI authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ip
+
+import (
+	"fmt"
+	"syscall"
+	"time"
+
+	"github.com/vishvananda/netlink"
+)
+
+const SETTLE_INTERVAL = 50 * time.Millisecond
+
+// SettleAddresses waits for all addresses on a link to leave tentative state.
+// This is particularly useful for ipv6, where all addresses need to do DAD.
+// There is no easy way to wait for this as an event, so just loop until the
+// addresses are no longer tentative.
+// If any addresses are still tentative after timeout seconds, then error.
+func SettleAddresses(ifName string, timeout int) error {
+	link, err := netlink.LinkByName(ifName)
+	if err != nil {
+		return fmt.Errorf("failed to retrieve link: %v", err)
+	}
+
+	deadline := time.Now().Add(time.Duration(timeout) * time.Second)
+	for {
+		addrs, err := netlink.AddrList(link, netlink.FAMILY_ALL)
+		if err != nil {
+			return fmt.Errorf("could not list addresses: %v", err)
+		}
+
+		if len(addrs) == 0 {
+			return nil
+		}
+
+		ok := true
+		for _, addr := range addrs {
+			if addr.Flags&(syscall.IFA_F_TENTATIVE|syscall.IFA_F_DADFAILED) > 0 {
+				ok = false
+				break // Break out of the `range addrs`, not the `for`
+			}
+		}
+
+		if ok {
+			return nil
+		}
+		if time.Now().After(deadline) {
+			return fmt.Errorf("link %s still has tentative addresses after %d seconds",
+				ifName,
+				timeout)
+		}
+
+		time.Sleep(SETTLE_INTERVAL)
+	}
+}