"reflect"
	"strings"
	"testing"
)

var parseMACTests = []struct {
	in  string
	out HardwareAddr
	err string
}{
	// See RFC 7042, Section 2.1.1.
	{"00:00:5e:00:53:01", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
	{"00-00-5e-00-53-01", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
	{"0000.5e00.5301", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},

	// See RFC 7042, Section 2.2.2.

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package net

const hexDigit = "0123456789abcdef"

// A HardwareAddr represents a physical hardware address.
type HardwareAddr []byte

func (a HardwareAddr) String() string {
	if len(a) == 0 {
		return ""
	}
	buf := make([]byte, 0, len(a)*3-1)
	for i, b := range a {
		if i > 0 {
			buf = append(buf, ':')
		}

			itfAddrsPairs: []InterfaceAddrsPair{
				{
					itf:   net.Interface{Index: 0, MTU: 0, Name: "eth0", HardwareAddr: nil, Flags: 0},
					addrs: []net.Addr{&net.IPNet{IP: netutils.ParseIPSloppy("10.20.30.51"), Mask: net.CIDRMask(24, 32)}},
				},
				{
					itf:   net.Interface{Index: 2, MTU: 0, Name: "eth1", HardwareAddr: nil, Flags: 0},
					addrs: []net.Addr{&net.IPNet{IP: netutils.ParseIPSloppy("100.200.201.1"), Mask: net.CIDRMask(24, 32)}},

		}

		if len(line) > 0 && len(line)%2 == 0 {
			ifc.HardwareAddr = make([]byte, len(line)/2)
			var ok bool
			for i := range ifc.HardwareAddr {
				j := (i + 1) * 2
				ifc.HardwareAddr[i], ok = xtoi2(line[i*2:j], 0)
				if !ok {
					ifc.HardwareAddr = ifc.HardwareAddr[:i]
					break
				}
			}
		}

		ifc.Flags = FlagUp | FlagRunning | FlagBroadcast | FlagMulticast

			}
			ift[n].Index = m.Index
			ift[n].Name = m.Name
			ift[n].Flags = linkFlags(m.Flags)
			if sa, ok := m.Addrs[syscall.RTAX_IFP].(*route.LinkAddr); ok && len(sa.Addr) > 0 {
				ift[n].HardwareAddr = make([]byte, len(sa.Addr))
				copy(ift[n].HardwareAddr, sa.Addr)
			}
			for _, sys := range m.Sys() {
				if imx, ok := sys.(*route.InterfaceMetrics); ok {
					ift[n].MTU = imx.MTU
					break
				}
			}
			n++

	for _, ll := range lls {
		if ifindex != 0 && ifindex != ll.Index {
			continue
		}
		ifi := Interface{Index: ll.Index, MTU: ll.MTU, Name: ll.Name, Flags: linkFlags(ll.Flags)}
		if len(ll.Addr) > 0 {
			ifi.HardwareAddr = HardwareAddr(ll.Addr)
		}
		ift = append(ift, ifi)
	}
	return ift, nil
}

func linkFlags(rawFlags int) Flags {
	var f Flags
	if rawFlags&syscall.IFF_UP != 0 {
		f |= FlagUp
	}

			}
			if aa.Mtu == 0xffffffff {
				ifi.MTU = -1
			} else {
				ifi.MTU = int(aa.Mtu)
			}
			if aa.PhysicalAddressLength > 0 {
				ifi.HardwareAddr = make(HardwareAddr, aa.PhysicalAddressLength)
				copy(ifi.HardwareAddr, aa.PhysicalAddress[:])
			}
			ift = append(ift, ifi)
			if ifindex == ifi.Index {
				break
			}
		}
	}
	return ift, nil
}

				sdl := (*rawSockaddrDatalink)(unsafe.Pointer(&tab[syscall.SizeofIfMsghdr]))

				ifi := &Interface{Index: int(ifm.Index), Flags: linkFlags(ifm.Flags)}
				ifi.Name = string(sdl.Data[:sdl.Nlen])
				ifi.HardwareAddr = sdl.Data[sdl.Nlen : sdl.Nlen+sdl.Alen]

				// Retrieve MTU
				ifr := &ifreq{}
				copy(ifr.Name[:], ifi.Name)
				err = unix.Ioctl(sock, syscall.SIOCGIFMTU, unsafe.Pointer(ifr))
				if err != nil {

	Index        int          // positive integer that starts at one, zero is never used
	MTU          int          // maximum transmission unit
	Name         string       // e.g., "en0", "lo0", "eth0.100"
	HardwareAddr HardwareAddr // IEEE MAC-48, EUI-48 and EUI-64 form
	Flags        Flags        // e.g., FlagUp, FlagLoopback, FlagMulticast
}

type Flags uint

const (

)

func makeIntf(index int, name string, flags net.Flags) net.Interface {
	mac := net.HardwareAddr{0, 0x32, 0x7d, 0x69, 0xf7, byte(0x30 + index)}
	return net.Interface{
		Index:        index,
		MTU:          1500,
		Name:         name,
		HardwareAddr: mac,
		Flags:        flags}
}

var (
	downIntf     = makeIntf(1, "eth3", flagDown)