code/Debug/controllers/ConfigController.php
public function downloadAction()
    {
        $type = $this->getRequest()->getParam('type', 'xml');
        /** @var Mage_Core_Model_Config_Element $configNode */
        $configNode = Mage::app()->getConfig()->getNode();

        switch ($type) {
            case 'txt';
                $this->downloadAsText($configNode);
                break;
            case 'xml':
            default:
                $this->downloadAsXml($configNode);
        }
    }
public function downloadAction()
    {
        $type = $this->getRequest()->getParam('type', 'xml');
        /** @var Mage_Core_Model_Config_Element $configNode */
        $configNode = Mage::app()->getConfig()->getNode();

        switch ($type) {
            case 'txt';
                $this->downloadAsText($configNode);
                break;
            case 'xml':
            default:
                $this->downloadAsXml($configNode);
        }
    }
Download configuration as text or xml action