pkt_arp.erl

%% Copyright (c) 2009-2015, Michael Santos <michael.santos@gmail.com>
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-module(pkt_arp).

-include("pkt_ether.hrl").
-include("pkt_arp.hrl").

-export([codec/1]).

codec(<<Hrd:16, Pro:16,
    Hln:8, Pln:8, Op:16,
    Sha:6/bytes,
    SA1:8, SA2:8, SA3:8, SA4:8,
    Tha:6/bytes,
    DA1:8, DA2:8, DA3:8, DA4:8,
    Payload/binary>>
) ->
    {#arp{
        hrd = Hrd, pro = Pro,
        hln = Hln, pln = Pln, op = Op,
        sha = Sha,
        sip = {SA1,SA2,SA3,SA4},
        tha = Tha,
        tip = {DA1,DA2,DA3,DA4}
    }, Payload};
codec(#arp{
        hrd = Hrd, pro = Pro,
        hln = Hln, pln = Pln, op = Op,
        sha = Sha,
        sip = {SA1,SA2,SA3,SA4},
        tha = Tha,
        tip = {DA1,DA2,DA3,DA4}
    }) ->
    <<Hrd:16, Pro:16,
    Hln:8, Pln:8, Op:16,
    Sha:6/bytes,
    SA1:8, SA2:8, SA3:8, SA4:8,
    Tha:6/bytes,
    DA1:8, DA2:8, DA3:8, DA4:8>>.