Adds delete by IP excluded IP array, and config to exclude threads from delete by IP

inc/config.php

@@ -1375,6 +1375,11 @@
  *  Mod settings
  * ====================
  */
+    //  Exclude these IPs from "delete by IP", meaning clicking D+ or D++ won't affect these IPs.
+    $config['deletebyip_excluded_ips'] = array();
+
+    // If true, D+ and D++ won't affect threads. This means threads will need to  be deleted manually (using D).
+    $config['deletebyip_exclude_threads'] = false;
 
     // Limit how many bans can be removed via the ban list. Set to false (or zero) for no limit.
     $config['mod']['unban_limit'] = false;

inc/mod/pages.php

@@ -2214,14 +2214,22 @@ function mod_deletebyip($boardName, $post, $global = false) {
     if (!$ip = $query->fetchColumn())
         error($config['error']['invalidpost']);
 
-    // HACK: Prevent D+ or D++ deletion of Tor node or migration placeholder IP
-    if ($ip == "127.0.0.1" || $ip == "127.0.0.2") {error("Don't nuke ".$ip);}
+    if (in_array($ip, $config['deletebyip_excluded_ips'])) {
+        error("The following IP is protected by the deletebyip_excluded_ips configuration ".$ip);
+    }
+
+    $threadFilter = $config['deletebyip_exclude_threads'] ? "" : "AND `thread` IS NOT NULL";
 
     $boards = $global ? listBoards() : array(array('uri' => $boardName));
 
     $query = '';
     foreach ($boards as $_board) {
-        $query .= sprintf("SELECT `thread`, `id`, '%s' AS `board` FROM ``posts_%s`` WHERE `ip` = :ip UNION ALL ", $_board['uri'], $_board['uri']);
+        $query .= sprintf(
+            "SELECT `thread`, `id`, '%s' AS `board` FROM ``posts_%s`` WHERE `ip` = :ip %s UNION ALL ",
+            $_board['uri'],
+            $_board['uri'],
+            $threadFilter
+        );
     }
     $query = preg_replace('/UNION ALL $/', '', $query);