File: //usr/share/doc/perl-Archive-Zip/examples/ziptest.pl
#!/usr/bin/perl -w
# $Revision: 1.7 $
# Lists the zipfile given as a first argument and tests CRC's.
# Usage:
#	perl ziptest.pl zipfile.zip
use strict;
use Archive::Zip qw(:ERROR_CODES :CONSTANTS);
package CRCComputingFileHandle;
use Archive::Zip::MockFileHandle;
use vars qw( @ISA );
@ISA = qw( Archive::Zip::MockFileHandle );
my $crc;
sub writeHook {
    my $self   = shift;
    my $bytes  = shift;
    my $length = length($bytes);
    $crc = Archive::Zip::computeCRC32($bytes, $crc);
}
sub resetCRC { $crc = 0 }
sub crc { $crc }
package main;
die "usage: $0 zipfile.zip\n"
  if (scalar(@ARGV) != 1);
my $zip    = Archive::Zip->new();
my $status = $zip->read($ARGV[0]);
exit $status if $status != AZ_OK;
print " Length    Size         Last Modified         CRC-32  Name\n";
print "-------- --------  ------------------------  -------- ----\n";
my $fh = CRCComputingFileHandle->new();
my @errors;
foreach my $member ($zip->members()) {
    my $compressedSize = $member->compressedSize();
    $fh->resetCRC();
    $member->desiredCompressionMethod(COMPRESSION_STORED);
    $status = $member->extractToFileHandle($fh);
    exit $status if $status != AZ_OK;
    my $crc = $fh->crc();
    my $ct = scalar(localtime($member->lastModTime()));
    chomp($ct);
    printf(
        "%8d %8d  %s  %08x %s\n",
        $member->uncompressedSize(),
        $compressedSize, $ct, $member->crc32(), $member->fileName());
    if ($member->crc32() != $crc) {
        push(
            @errors,
            sprintf(
                "Member %s CRC error: file says %08x computed: %08x\n",
                $member->fileName(), $member->crc32(), $crc
            ));
    }
}
if (scalar(@errors)) {
    print join("\n", @errors);
    die "CRC errors found\n";
} else {
    print "All CRCs check OK\n";
}