#!/usr/bin/env perl
#
# %CopyrightBegin%
#
# Copyright Ericsson AB 2001-2016. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# %CopyrightEnd%
#
use strict;
for (@ARGV) {
open(IN, "<$_") or do {warn "skipping $_:$!\n"; next};
my $data;
sysread(IN, $data, 10000000);
close IN;
my $new_file = eval {slim_beam($data)};
open(OUT, ">$_") or die "Failed to write $_:$!\n";
print OUT $new_file;
close OUT;
}
# Bug in 5.6.0: The following doesn't work.
#local $/;
#while (<>) {
# my $new_file = eval {slim_beam($_)};
# if ($@) {
# ...
# } else {
# ...
# }
#}
sub slim_beam {
my($beam) = @_;
my $size_left = length($beam);
my @chunk;
die "can't read Beam files for OTP R4 or earlier (sorry)"
if $beam =~ /^\x7fBEAM!/;
#
# Read and verify the head of the IFF file.
#
my ($id, $size, $beam_id) = unpack("a4Na4", $beam);
die "not a BEAM file: no IFF 'FOR1' chunk"
unless $id eq 'FOR1';
$size_left -= 8;
die "form size $size greater than size ", $size_left, " of module"
if $size > $size_left;
$size_left -= 4;
die "not a BEAM file: IFF form type is not 'BEAM'"
unless $beam_id eq 'BEAM';
#
# Read all IFF chunks.
#
$beam = substr($beam, 12, $size_left);
while ($size_left > 0) {
($id, $size) = unpack("a4N", $beam);
$size_left -= 8;
die "chunk size $size greater than size ", $size_left, " of module"
if $size > $size_left;
$size = 4*int(($size+3)/4);
my $chunk = substr($beam, 0, $size+8);
$beam = substr($beam, 8+$size);
$size_left = length($beam);
push(@chunk, $chunk)
unless $id eq 'LocT' || $id eq 'CInf';
}
#
# Create new Beam file.
#
my $new_file = join('', @chunk);
"FOR1" . pack("N", length($new_file)+4) . "BEAM" . $new_file;
}
