firewall: skip empty lines and // type comments too

src/etc/inc/filter.inc

@@ -198,8 +198,10 @@ function process_alias_urltable($name, $url, $freq, $forceupdate = false)
         $verify_ssl = isset($config['system']['checkaliasesurlcert']);
         if (download_file($url, "{$urltable_filename}.tmp", $verify_ssl)) {
             foreach (preg_split('/[\n\r]+/', file_get_contents("{$urltable_filename}.tmp"), -1, PREG_SPLIT_NO_EMPTY) as $line) {
-                $line = trim($line); // remove leading spaces
-                if ($line[0] != '#') {
+                $line = trim($line);
+                if (!strlen($line) || !strncmp($line, '#', 1) || !strncmp($line, '//', 2)) {
+                    continue;
+                }
                 // cleanse line item
                 $line = preg_split('/\s+/', $line)[0];
                 if ($alias_type == "urltable_ports") {
@@ -228,7 +230,6 @@ function process_alias_urltable($name, $url, $freq, $forceupdate = false)
                     fflush($output_file_handle);
                 }
             }
-            }
             fclose($output_file_handle);
 
             if ($alias_type == "urltable_ports") {