#!/usr/bin/perl -w

#
# This program will outline the top users of a file system.
#

use strict;
use Getopt::Long;
use File::Recurse;

my $max_users=10;
my @fs=();
my @file_list=();
my @dir_list=();
my %filehash;

GetOptions( "fs=s@"     => \@fs,
            "users=i"   => \$max_users
          );

&help() unless @fs;

foreach my $fs (@fs) {
    my %sorthash;
    undef(%filehash);
    print "$fs:\n";

    recurse ( sub {
                my ($uid, $size) = (stat)[4, 7];
                $filehash{$uid} += $size;
              }, $fs);
 
    my $count = 0;
    foreach my $uid ( sort {$filehash{$b} <=> $filehash{$a} } keys %filehash)
{
        next if ($uid eq "");
        last unless $count < $max_users;
        my $name = (getpwuid($uid)) || "uid($uid)";
        &printUser($name, $filehash{$uid});
        $count++;
    }
 
    print "\n";
}
 
 
sub printUser {
    my ( $user, $size ) = @_;
    my $label;
    my @labels = qw ( bytes Kb Mb Gb );
    foreach my $power (reverse 0..$#labels){
     if($size >= (1024**$power)){
       $label = $labels[$power];
       $size /= (1024**$power);
       last;
     }
    }
    printf "    %-12s is using %7.2f %s\n", $user, $size, $label;
}
 
 
sub help() {
    print "Syntax:\n\t$0 [--users=i] --fs=/path1 [--fs=/path2] ...\n";
    exit(0);
}