typedef filter_token filter_type_t;
typedef hook_token filter_result_t;
typedef param_token filter_param_id_t;
typedef filter_token filter_type_t;
typedef hook_token filter_result_t;
typedef param_token filter_param_id_t;
typedef void (*filter_async_handler_t)(filter_context_t *context,
const filter_hook_t *result);
typedef void (*filter_async_handler_t)(filter_context_t *context,
const filter_hook_t *result);