#!/usr/bin/perl

# Byteshifting program for mozilla's netscape.cfg files

# Old netscape 4.x uses a bytechift of 7
#   To decode: moz-byteshift.pl -s -7 <netscape.cfg >netscape.cfg.txt
#   To encode: moz-byteshift.pl -s  7 <netscape.cfg.txt >netscape.cfg

# Mozilla uses a byteshift of 13
#   To decode: moz-byteshift.pl -s -13 <netscape.cfg >netscape.cfg.txt
#   To encode: moz-byteshift.pl -s  13 <netscape.cfg.txt >netscape.cfg

use strict;
use Getopt::Std;
use vars qw/$opt_s/;

getopts("s:");
die "Missing shift\n" if (!defined $opt_s);

my $buffer;
while(1) {
	my $n=sysread STDIN, $buffer, 1;
	last if ($n eq 0);
	my $byte = unpack("c", $buffer);
	$byte += 512 + $opt_s;
	$buffer = pack("c", $byte);
	syswrite STDOUT, $buffer, 1;
}