%%% Copyright (c) 2011-2023 Michael Santos <michael.santos@gmail.com>. All
%%% rights reserved.
%%%
%%% Redistribution and use in source and binary forms, with or without
%%% modification, are permitted provided that the following conditions
%%% are met:
%%%
%%% 1. Redistributions of source code must retain the above copyright notice,
%%% this list of conditions and the following disclaimer.
%%%
%%% 2. Redistributions in binary form must reproduce the above copyright
%%% notice, this list of conditions and the following disclaimer in the
%%% documentation and/or other materials provided with the distribution.
%%%
%%% 3. Neither the name of the copyright holder nor the names of its
%%% contributors may be used to endorse or promote products derived from
%%% this software without specific prior written permission.
%%%
%%% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
%%% "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
%%% LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
%%% A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
%%% HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
%%% SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
%%% TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
%%% PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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%%% SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

-define(SIZEOF_INT, 4).
-define(SIZEOF_UNSIGNED_INT, ?SIZEOF_INT).
-define(UINT16(N), N:2 / native - unsigned - integer - unit:8).
-define(UINT32(N), N:4 / native - unsigned - integer - unit:8).

% ifconfig
-define(IFF_UP, 1 bsl 0).
-define(IFF_POINTOPOINT, 1 bsl 5).
-define(IFF_RUNNING, 1 bsl 6).

% Ioctl defines
-define(TUNSETNOCSUM, ?IOW($T, 200, ?SIZEOF_INT)).
-define(TUNSETDEBUG, ?IOW($T, 201, ?SIZEOF_INT)).
-define(TUNSETIFF, ?IOW($T, 202, ?SIZEOF_INT)).
-define(TUNSETPERSIST, ?IOW($T, 203, ?SIZEOF_INT)).
-define(TUNSETOWNER, ?IOW($T, 204, ?SIZEOF_INT)).
-define(TUNSETLINK, ?IOW($T, 205, ?SIZEOF_INT)).
-define(TUNSETGROUP, ?IOW($T, 206, ?SIZEOF_INT)).
-define(TUNGETFEATURES, ?IOR($T, 207, ?SIZEOF_UNSIGNED_INT)).
-define(TUNSETOFFLOAD, ?IOW($T, 208, ?SIZEOF_UNSIGNED_INT)).
-define(TUNSETTXFILTER, ?IOW($T, 209, ?SIZEOF_UNSIGNED_INT)).
-define(TUNGETIFF, ?IOR($T, 210, ?SIZEOF_UNSIGNED_INT)).
-define(TUNGETSNDBUF, ?IOR($T, 211, ?SIZEOF_INT)).
-define(TUNSETSNDBUF, ?IOW($T, 212, ?SIZEOF_INT)).

% TUNSETIFF ifr flags
-define(IFF_TUN, 16#0001).
-define(IFF_TAP, 16#0002).
-define(IFF_MULTI_QUEUE, 16#0100).
-define(IFF_NO_PI, 16#1000).
-define(IFF_ONE_QUEUE, 16#2000).
-define(IFF_VNET_HDR, 16#4000).
-define(IFF_TUN_EXCL, 16#8000).

-record(tun_pi, {
    % 2/native-unsigned-integer-unit:8
    flags,
    % 2/native-unsigned-integer-unit:8
    proto,
    buf
}).

-define(TUN_FLT_ALLMULTI, 16#0001).

-record(tun_filter, {
    % TUN_FLT_ flags: 2/native-unsigned-integer-unit:8
    flags,
    % 2/native-unsigned-integer-unit:8
    count,
    addr
}).