/* * Copyright (C) 2016, 2017 "IoT.bzh" * Author: José Bollo <jose.bollo@iot.bzh> * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #pragma once /* avoid inclusion of <json-c/json.h> */ struct json_object; /* * Interface for handling requests. * It records the functions to be called for the request. * Don't use this structure directly. * Use the helper functions documented below. */ struct afb_event_itf { /* CAUTION: respect the order, add at the end */ int (*broadcast)(void *closure, struct json_object *obj); int (*push)(void *closure, struct json_object *obj); void (*drop)(void *closure); const char *(*name)(void *closure); }; /* * Describes the request of afb-daemon for bindings */ struct afb_event { const struct afb_event_itf *itf; /* the interface to use */ void *closure; /* the closure argument for functions of 'itf' */ }; /* * Checks wether the 'event' is valid or not. * * Returns 0 if not valid or 1 if valid. */ static inline int afb_event_is_valid(struct afb_event event) { return event.itf != NULL; } /* * Broadcasts widely the 'event' with the data 'object'. * 'object' can be NULL. * * For convenience, the function calls 'json_object_put' for 'object'. * Thus, in the case where 'object' should remain available after * the function returns, the function 'json_object_get' shall be used. * * Returns the count of clients that received the event. */ static inline int afb_event_broadcast(struct afb_event event, struct json_object *object) { return event.itf->broadcast(event.closure, object); } /* * Pushes the 'event' with the data 'object' to its observers. * 'object' can be NULL. * * For convenience, the function calls 'json_object_put' for 'object'. * Thus, in the case where 'object' should remain available after * the function returns, the function 'json_object_get' shall be used. * * Returns the count of clients that received the event. */ static inline int afb_event_push(struct afb_event event, struct json_object *object) { return event.itf->push(event.closure, object); } /* * Drops the data associated to the 'event' * After calling this function, the event * MUST NOT BE USED ANYMORE. */ static inline void afb_event_drop(struct afb_event event) { event.itf->drop(event.closure); } /* * Gets the name associated to the 'event'. */ static inline const char *afb_event_name(struct afb_event event) { return event.itf->name(event.closure); }