#!/usr/bin/env perl

$FILE="/etc/mnttab";
open FILE or die "Can't open $FILE: $!";
while (<FILE>) {
        chomp;
        ($lv, $fs) = split;
        push @mnttab, ($lv, $fs)
}
%mnttab = @mnttab;

open(LVM, "vgdisplay -Fv |") || die "Can't fork vgdisplay: $!";
while (<LVM>) {
        chomp;
        $h_ref = {};
        %{ $h_ref } = split(/[=:]/);
        if ( $h_ref->{vg_name} && $a_ref->[0]->{vg_name} ) {
                push @vgdisplay, $a_ref;
                $a_ref = ()
        }
        delete $a_ref->[0] unless ( %{ $a_ref->[0] } );
        push @{ $a_ref }, $h_ref
}
push @vgdisplay, $a_ref if ref($a_ref);

for $i ( @vgdisplay ) {
        print "Detected VG: $i->[0]->{vg_name}\n";
        print "The PE size is: $i->[0]->{pe_size}\n";
        $count = 2*$i->[0]->{pe_size};
        for ( $j = 1; $i->[$j]->{lv_name}; $j++ ) {
                next unless defined $mnttab{$i->[$j]->{lv_name}};
                print "Detected LV: $i->[$j]->{lv_name}\t";
                print "The LV is mounted on: $mnttab{$i->[$j]->{lv_name}}\n";
                print "Changing directory to the $mnttab{$i->[$j]->{lv_name}}/lost+found\n";
                chdir "$mnttab{$i->[$j]->{lv_name}}/lost+found" or warn "Can't cd to $mnttab{$i->[$j]->{lv_name}}/lost+found: $!\n" and next;
                print "Creating the dummy file: dummy\n";
                !system "dd if=/dev/zero of=dummy bs=1024k count=$count" or warn "Can't dd to file dummy\n";
        }
#       for ( ; $i->[$j]->{pv_name}; $j++ ) {
#               print "Detected PV: $i->[$j]->{pv_name}\n";
#       }
        print "########################################\n";
}

close(LVM) || die "Can't close vgdisplay: $!";