%% -*- erlang-indent-level: 2 -*-
%%--------------------------------------------------------------------
%% Author : Kostis Sagonas
%% Purpose : These tests are intended to test the construction and
%% matching of binaries using variable sizes
%% Notes :
%% - Added test that crashed BEAM compiler
%% - Added test that crashed when segments of size zero were used
%% and one that did not convert integers to floats when constructing
%% binaries.
%% - Added a construction test which crashed from core because of
%% problems with the effect flag (2004/11/15)
%%--------------------------------------------------------------------
-module(bs_var_segs).
-export([test/0]).
test() ->
N1 = 18,
A1 = 2,
A1 = match1(N1, <<1:12, 2:N1, A1:2>>),
A1 = match2(N1, <<1:12, 2:N1/integer-little, A1:2>>),
N3 = 3,
A3 = <<1,2,3>>,
B3 = 2,
{A3, B3} = match3(N3, <<1:12, A3:N3/binary, B3:4>>),
N4 = 12,
B4 = <<1,2,3>>,
A4 = 2,
{A4, B4} = match4(N4, <<1:N4, A4:4, B4/binary>>),
Y = <<5>>,
Y = match5(a, Y),
<<73>> = gen1(8, 0, <<73>>),
<<171>> = gen2(8, 7, 2#10101010101010101),
<<0:64>> = construct(),
<<0:32>> = construct2(0),
ok = in_guard(<<16#BCD:14,3:2>>, 16#BCD),
ok.
construct() ->
<<0:64/float>>.
construct2(X) ->
<<X:32/little>>.
match1(N, Bin) ->
<<1:12, 2:N, A:2>>=Bin,
A.
match2(N, Bin) ->
<<1:12, 2:N/integer-little, A:2>>=Bin,
A.
match3(N, Bin) ->
<<1:12, A:N/binary, B:4>>=Bin,
{A,B}.
match4(N, Bin) ->
<<1:N, A:4, B/binary>>=Bin,
{A,B}.
match5(X, Y) ->
case X of
a ->
Y2 = 8
end,
<<5:Y2>> = Y.
gen1(N, S, A) ->
<<A:S/binary-unit:1, A:(N-S)/binary-unit:1>>.
gen2(N, S, A) ->
<<A:S/little, A:(N-S)/little>>.
in_guard(Bin, A) when <<A:14,3:2>> == Bin -> ok;
in_guard(_, _) -> no.
