PHP simplexml_load_string のエラーハンドリングを一生懸命やる!

gistfile1.php

function getXmlData($rss_url = NULL) {
    set_error_handler(function($errno, $errstr, $errfile, $errline) {  
        throw new Exception($errstr, $errno);  
    });  

    try {
        $search = array("\0", "\x01", "\x02", "\x03", "\x04", "\x05","\x06", "\x07", "\x08", "\x0b", "\x0c", "\x0e", "\x0f");

        $options = array(
            'http' => array(
            'method' => 'GET',
            'header' => 'User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.94 Safari/537.36',
            ),
        );
        $context = stream_context_create($options);
        $xml_context = file_get_contents($rss_url, false, $context);
        $xml_context = str_replace($search, '', $xml_context);  

        if (mb_detect_encoding($xml_context, 'UTF-8', true) === false) { 
            $xml_context = utf8_encode($xml_context); 
        }

        if (strpos($xml_context, '<?xml', 0) === false){
            echo "×:Error:". $rss_url . "\n";
            return false;
        }

        $xml = simplexml_load_string($xml_context);

        if ($xml === false) {
            echo "Failed loading XML\n";
            foreach(libxml_get_errors() as $error) {
                echo "\t", $error->message;
            }
            return false;
        }
        restore_error_handler();
    } catch (Exception $ex) {
        restore_error_handler();  
        echo "×:Exception". $ex . "\n";  
        echo "×:Error:". $rss_url . "\n";
        return false;
    }

    return $xml;
}