pre-receive hook to deny pushing big files

pre-receive

#!/usr/bin/perl -wl
use strict;

my $limit = 1024 * 1024;
my $hasBadFiles;

while (<>) {
    chomp;
    my ($old, $new, $ref) = split / /, $_;

    my $log = ($old =~ /^0+$/ ? `git log --pretty=%H` : `git log --pretty=%H $old..$new`);
    for my $commit (split /\n/, $log) {
        for my $blob (split /\n/, `git ls-tree -l -r $commit`) {
            my (undef, $type, undef, $size, $name) = split /\s+/, $blob;
            next if $type ne 'blob';
            if ($size > $limit) {
                print "Size of file '$name' in commit $commit is over limit ($limit bytes)";
                $hasBadFiles = 1;
            }
        }
    }
}

$hasBadFiles and exit 1;