// license that can be found in the LICENSE file.

package net

import (
	"fmt"
	"reflect"
	"runtime"
	"testing"
)

// loopbackInterface returns an available logical network interface
// for loopback tests. It returns nil if no suitable interface is
// found.
func loopbackInterface() *Interface {
	ift, err := Interfaces()
	if err != nil {
		return nil
	}
	for _, ifi := range ift {

	}
	ip, ok := hasRoutableIP(network, ifi)
	if !ok {
		return nil, errNoAvailableAddress
	}
	return ip, nil
}

// LoopbackInterface returns an available logical network interface
// for loopback test.
func LoopbackInterface() (*net.Interface, error) {
	ift, err := net.Interfaces()
	if err != nil {
		return nil, errNoAvailableInterface
	}
	for _, ifi := range ift {

		resolveIPAddrTests = append(resolveIPAddrTests, resolveIPAddrTest{"ip", "::", &IPAddr{IP: IPv6unspecified}, nil})
	}

	ifi := loopbackInterface()
	if ifi != nil {
		index := fmt.Sprintf("%v", ifi.Index)
		resolveTCPAddrTests = append(resolveTCPAddrTests, []resolveTCPAddrTest{

		t.Skip("IPv4 is not supported")
	}

	closer := func(cs []*UDPConn) {
		for _, c := range cs {
			if c != nil {
				c.Close()
			}
		}
	}

	for _, ifi := range []*Interface{loopbackInterface(), nil} {
		// Note that multicast interface assignment by system
		// is not recommended because it usually relies on
		// routing stuff for finding out an appropriate
		// nexthop containing both network and link layer

	"runtime"
	"testing"
	"time"
)

func BenchmarkUDP6LinkLocalUnicast(b *testing.B) {
	testHookUninstaller.Do(uninstallTestHooks)

	if !supportsIPv6() {
		b.Skip("IPv6 is not supported")
	}
	ifi := loopbackInterface()
	if ifi == nil {
		b.Skip("loopback interface not found")
	}
	lla := ipv6LinkLocalUnicastAddr(ifi)
	if lla == "" {
		b.Skip("IPv6 link-local unicast address not found")
	}