CI_Cart::_save_cart PHP Method

    protected function _save_cart()
    {
        // Let's add up the individual prices and set the cart sub-total
        $this->_cart_contents['total_items'] = $this->_cart_contents['cart_total'] = 0;
        foreach ($this->_cart_contents as $key => $val) {
            // We make sure the array contains the proper indexes
            if (!is_array($val) or !isset($val['price'], $val['qty'])) {
                continue;
            }
            $this->_cart_contents['cart_total'] += $val['price'] * $val['qty'];
            $this->_cart_contents['total_items'] += $val['qty'];
            $this->_cart_contents[$key]['subtotal'] = $this->_cart_contents[$key]['price'] * $this->_cart_contents[$key]['qty'];
        }
        // Is our cart empty? If so we delete it from the session
        if (count($this->_cart_contents) <= 2) {
            $this->CI->session->unset_userdata('cart_contents');
            // Nothing more to do... coffee time!
            return FALSE;
        }
        // If we made it this far it means that our cart has data.
        // Let's pass it to the Session class so it can be stored
        $this->CI->session->set_userdata(array('cart_contents' => $this->_cart_contents));
        // Woot!
        return TRUE;
    }