    public static function isPublic($s) {
        if ($s == null) {
            return false;
        }
        while ($s->public && $s->parent > 0) {
            $s = new section($s->parent);
        }
        $lineage = (($s->public) ? 1 : 0);
        return $lineage;
    }
The software constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.