rebar.config.script

PFRING = fun(CONFIG) -> case os:getenv("PFRING") of
    false ->
        CONFIG;
    Value ->
        case filelib:is_dir(Value) of
            true ->
                case lists:keysearch(port_env, 1, CONFIG) of
                    {value, {port_env, Flags}} ->
                        {"EXE_LDFLAGS", LDFLAGS} = hd(Flags),
                        NewFlags = LDFLAGS ++ " -L " ++ Value ++ " -lpfring -lpthread -lnuma -lrt",
                        NewLDFLAGS = lists:keyreplace("EXE_LDFLAGS", 1, Flags, {"EXE_LDFLAGS", NewFlags}),
                        lists:keyreplace(port_env, 1, CONFIG, {port_env, NewLDFLAGS});
                    _ -> CONFIG
                end;
            _ -> CONFIG
        end
    end
end,
Pcap_create = fun(CONFIG) ->
    Check = "
#include <pcap.h>
int main(int argc, char *argv[])
{
    char errbuf[PCAP_ERRBUF_SIZE];
    (void)pcap_create(NULL, errbuf);
    return 0;
}",
    ok = file:write_file("test_pcap_create.c", Check),
    Retval = os:cmd("cc -o /dev/null test_pcap_create.c -lpcap > /dev/null 2>&1; printf \"%d\" $?"),
    file:delete("test_pcap_create.c"),
    case Retval of
        "0" ->
            Env = case os:getenv("EPCAP_CFLAGS") of
            false -> "";
            N -> N
            end,
            os:putenv("EPCAP_CFLAGS", Env ++ " -DHAVE_PCAP_CREATE"),
            CONFIG;
        _ ->
            CONFIG
    end
end,
lists:foldl(fun(Fun, Cfg) ->
        Fun(Cfg)
    end,
    CONFIG,
    [PFRING, Pcap_create]
    ).