xNightR00T File Manager

#! /usr/bin/perl

# usage: get-option OPTION
#
# Read boot option.
#
# OPTION is either of the form 'key=value' or 'key="value"' or just 'key'.
#
# The option value is written into the file passed via 'PBL_RESULT' environment var.
# Either 'option=value', or 'option', or nothing is returned.

use strict;

my $file = "/etc/default/grub";

my $opt = shift;

my $opt_name = $opt;

if($opt_name =~ s/=("?).*//) {
  $opt =~ s/"/\\"/g;
}

exit 1 if $opt_name eq "";

open my $f, $file or die "$file: $!\n";
my @lines = (<$f>);
close $f;

my $option;

for (@lines) {
  if(/^(GRUB_CMDLINE_LINUX_DEFAULT)=(.*)/) {
    my $val = $2;

    $val =~ s/(^"\s*|\s*"\s*$)//g;

    if(
      $val =~ /(^|\s)($opt=(\\"[^"]*\\"\s*))/ ||
      $val =~ /(^|\s)($opt((\s|$)|(=\S*\s*)))/
    ) {
      $option = $2;
      $option =~ s/^\s+|\s+$//g;
    }
  }
}

if($option && open my $f, ">", $ENV{PBL_RESULT}) {
  print $f $option;
  close $f;
}

exit 0;