adblock_auto/addchecksum.pl

84 lines
2.1 KiB
Perl
Executable File

#!/usr/bin/perl
#############################################################################
# To add a checksum to a subscription file, run the script like this: #
# perl addChecksum.pl subscription.txt #
#############################################################################
use strict;
use warnings;
use Digest::MD5 qw(md5_base64);
die "Usage: $^X $0 subscription.txt\n" unless @ARGV;
#my $file = $ARGV[0];
foreach my $file (@ARGV) {
my $data = readFile($file);
# Get existing checksum.
$data =~ /^.*!\s*checksum[\s\-:]+([\w\+\/=]+).*\n/gmi;
my $oldchecksum = $1;
# Remove already existing checksum.
$data =~ s/^.*!\s*checksum[\s\-:]+([\w\+\/=]+).*\n//gmi;
# Calculate new checksum: remove all CR symbols and empty
# lines and get an MD5 checksum of the result (base64-encoded,
# without the trailing = characters).
my $checksumData = $data;
$checksumData =~ s/\r//g;
$checksumData =~ s/\n+/\n/g;
# Calculate new checksum
my $checksum = md5_base64($checksumData);
# If the old checksum matches the new one bail.
#if ($checksum eq $oldchecksum)
#{
# $data = ();
# next;
#}
# Update the date.
my @months = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime();
$year += 1900; # Year is years since 1900.
my $todaysdate = "$mday $months[$mon] $year";
$data =~ s/(^.*!.*Updated:\s*)(.*)\s*$/$1$todaysdate/gmi;
# Recalculate the checksum as we've altered the date.
$checksumData = $data;
$checksumData =~ s/\r//g;
$checksumData =~ s/\n+/\n/g;
$checksum = md5_base64($checksumData);
# Insert checksum into the file
$data =~ s/(\r?\n)/$1! Checksum: $checksum$1/;
writeFile($file, $data);
$data = ();
}
sub readFile
{
my $file = shift;
open(local *FILE, "<", $file) || die "Could not read file '$file'";
binmode(FILE);
local $/;
my $result = <FILE>;
close(FILE);
return $result;
}
sub writeFile
{
my ($file, $contents) = @_;
open(local *FILE, ">", $file) || die "Could not write file '$file'";
binmode(FILE);
print FILE $contents;
close(FILE);
}