sub _open_file
  {
    my($file_name,$mode) = @_;

    $mode = "r" if(!defined($mode));

    my $compress = 1;
    $compress = "" if($file_name =~ /\.xml$/i);

    if($mode eq "r")
      {
        my $fh = new IO::File($file_name);
        binmode $fh;

        my $f1 = "";

        while(!$fh->eof())
          {
            my $c = $fh->read($f1,1024*16,length($f1));
          }
        $fh = undef;

        my $f2 = "";
        if(defined($model_passphrase) && $model_passphrase ne "")
          {
            # Pad $f1 to the next 8 byte boundary
            if((length($f1) % 8) != 0)
              {
                $f1 .= "\x00" x (8 - (length($f1) % 8));
              }

            my $cipher =  new Crypt::Blowfish $model_passphrase;
            for(my $i=0;(8*$i)<length($f1);$i++)
              {
                $f2 .= $cipher->decrypt(substr($f1,8*$i,8));
              }
            $f2 =~ s/\x00+$//s;
          }
        else
          {
            $f2 = $f1;
          }

        # Just in case the file is big save some memory
        $f1 = "";

        my $f3 = "";
        if($compress)
          {
            $f3 = uncompress($f2);
          }
        else
          {
            $f3 = $f2;
          }
        return new IO::Scalar \$f3;
      }
    else
      {
        # When writing I want to first get the output, then compress
        # then encrypt, then write to the file.

        # So I have to create a handle that does some magic 
        # when it is closed
        my $buffer;
        return new IO::ActionOnClose(\$buffer,
                         action => \&_send_file,
                         args => [\$buffer,$file_name,$compress,$model_passphrase]);
      }
  }

}

sub _send_file
  {
    my($f3_ref,$file_name,$compress,$model_passphrase) = @_;

    # This is the reverse of what _open_file does for
    # read (even the variable names are the same)
    my $f2;
    if($compress)
      {
        $f2 = compress(${$f3_ref});
      }
    else
      {
        $f2 = ${$f3_ref};
      }
    my $f1 = "";
    if(defined($model_passphrase) && $model_passphrase ne "")
      {
        my $cipher =  new Crypt::Blowfish $model_passphrase;

        # Pad $f1 to the next 8 byte boundary
        if((length($f2) % 8) != 0)
          {
            $f2 .= "\x00" x (8 - (length($f2) % 8));
          }

        for(my $i=0;8*$i<length($f2);$i++)
          {
            $f1 .= $cipher->encrypt(substr($f2,8*$i,8));
          }
      }
    else
      {
        $f1 = $f2;
      }

    my $fh = new IO::File($file_name,"w");
    binmode $fh;
    $fh->syswrite($f1,length($f1));
    $fh->close();
  }