#!/usr/bin/perl -w

# splitgzip.pl
#
# written by Michael Holzt, <splitgzip@michael.holzt.de>, 5/2003
# slightly modified by an unknown contributor
#
# this code is declared public domain by the author

use strict;

my ($fn, $imglen, $image, $offset, $x, $output);

($fn) = @ARGV;
die "Usage: splitgzip.pl <imagefile>\n" if ( $fn eq '' );

print "Reading $fn...\n";
open(IN,"<$fn") or die "Can't open: $fn\n";
$imglen = read(IN,$image,2000000);
close(IN);

print "FIXME: \$imglen = $imglen\n";
print "Analysing $fn...\n";

$offset = 0;
$output = 0;

for ( $offset=0; $offset<$imglen; $offset++ )
{
  if ( ord(substr($image,$offset,1)) == 0x1F &&
       ord(substr($image,$offset+1,1)) == 0x8B &&
       ord(substr($image,$offset+2,1)) == 0x08 )
  {
    print "Found GZIP-Header... ";
    print "FIXME: found at offset $offset";

    close(OUT) if ( $output );

    $fn = '';
    $x  = 10;
    while ( ord(substr($image,$offset+$x,1)) != 0 )
    {
      $fn .= substr($image,$offset+$x,1);
      $x++;
    }
    print "Filename $fn.gz... writing...\n";
    open(OUT,">$fn.gz") or die "Can't open: $fn\n";
    $output = 1;
  }

  print OUT substr($image,$offset,1) if ( $output );
}

close(OUT) if ( $output );