#!/usr/bin/env perl

use strict;
use warnings;
use autodie;

my %dir_tree;
my $root_dir = '.';

build_dir_tree(\%dir_tree, $root_dir);

sub build_dir_tree {
    my ($tree, $path) = @_;

    opendir(my $dh, $path);

    for (readdir $dh) {
        next if /^(?:\.|\.\.)$/;

        if (-d "$path/$_") {
            $tree->{$_} = {};
            build_dir_tree($tree->{$_}, "$path/$_");
        }
        else {
            $tree->{$_} = -s "$path/$_";
        }
    }
}

{
    use Data::Dumper;
    local $Data::Dumper::Indent = 1;
    local $Data::Dumper::Sortkeys = 1;
    print Dumper \%dir_tree;
}