Don't allow users to post in locked threads'

inc/config.php

@@ -66,6 +66,7 @@
 	define('ERROR_FILEEXT',	'Unsupported image format.', true);
 	define('ERROR_NOBOARD',	'Invalid board!', true);
 	define('ERROR_NONEXISTANT', 'Thread specified does not exist.', true);
+	define('ERROR_LOCKED',	'Thread locked. You may not reply at this time.', true);
 	define('ERROR_NOPOST',	'You didn\'t make a post.', true);
 	define('ERR_INVALIDIMG','Invalid image.', true);
 	define('ERR_FILESIZE',	'Maximum file size: %maxsz% bytes<br>Your file\'s size: %filesz% bytes', true);
@@ -186,6 +187,8 @@
 	define('MOD_DELETEBYIP', MOD_BAN, true);
 	// Sticky a thread
 	define('MOD_STICKY', MOD_MOD, true);
+	// Lock a thread
+	define('MOD_LOCK', MOD_MOD, true);
 	
 	/* Administration */
 	// Display the contents of instant-config.php

inc/functions.php

@@ -118,6 +118,21 @@
 		}
 	}
 	
+	function threadLocked($id) {
+		global $board;
+		
+		$query = prepare(sprintf("SELECT `locked` FROM `posts_%s` WHERE `id` = :id AND `thread` IS NULL LIMIT 1", $board['uri']));
+		$query->bindValue(':id', $id, PDO::PARAM_INT);
+		$query->execute() or error(db_error());
+		
+		if(!$post = $query->fetch()) {
+			// Non-existant, so it can't be locked...
+			return false;
+		}
+		
+		return (bool) $post['locked'];
+	}
+	
 	function threadExists($id) {
 		global $board;
 		

post.php

@@ -70,6 +70,9 @@
 		if(!$OP && !threadExists($post['thread']))
 			error(ERROR_NONEXISTANT);
 		
+		if(!$OP && threadLocked($post['thread']))
+			error(ERROR_LOCKED);
+		
 		// Check for a file
 		if($OP) {
 			if(!isset($_FILES['file']['tmp_name']) || empty($_FILES['file']['tmp_name']))