perl version comparison

perl-version-compare.pl

# (before, after) if after > before; then return 1; else return 0;
sub is_newer_version
{
    my $before = shift;
    my $after = shift;

    _llog("Comparing versions ($before - $after)");

    my @b = split(/\./, $before);
    my @a = split(/\./, $after);

    my $cntb = scalar(@b);
    for(my $j; $j<$cntb; $j++)
    {
        if(!exists($a[$j]))
        {
            my $k=int($j+1);
            while(int($b[$k]) == 0)
            {
                if(!exists($b[$k+1]))
                {
                    last;
                }
                $k++;
            }
            if(int($b[$k]) == 0)
            {
                _llog("The versions are identical($before - $after), returning no");
                return 0;
            }
            return 0;
        }
        if(int($a[$j]) > int($b[$j]))
        {
            return 1;
        }
        if(int($a[$j]) < int($b[$j]))
        {
            return 0;
        }
        if(exists($a[$j+1]) && !exists($b[$j+1]))
        {
            my $k=int($j+1);
            while(int($a[$k]) == 0)
            {
                if(!exists($a[$k+1]))
                {
                    last;
                }
                $k++;
            }
            if(int($a[$k]) == 0)
            {
                _llog("The versions are identical($before - $after), returning no");
                return 0;
            }
            return 1;
        }
    }
return 0;
}