(svn r14514) -Codechange: use 'size' instead of 'length' for querystring and textbuf, explicitly say it includes the terminating zero

-Fix: one couldn't rename things with too long default/automatic name
-Fix: buffer overflow in console when too long (1024 bytes) command was entered

src/querystring_gui.h

@@ -41,10 +41,11 @@ struct QueryString {
 struct QueryStringBaseWindow : public Window, public QueryString {
 	char *edit_str_buf;
 	char *orig_str_buf;
-	const uint16 edit_str_size;
+	const uint16 edit_str_size; ///< maximum length of string (in bytes), including terminating '\0'
 
 	QueryStringBaseWindow(uint16 size, const WindowDesc *desc, WindowNumber window_number = 0) : Window(desc, window_number), edit_str_size(size)
 	{
+		assert(size != 0);
 		this->edit_str_buf = CallocT<char>(size);
 	}