MicroAPRS/bertos/mware/observer.h

96 lines
2.8 KiB
C

/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* As a special exception, you may use this file as part of a free software
* library without restriction. Specifically, if other files instantiate
* templates or use macros or inline functions from this file, or you compile
* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
* the GNU General Public License.
*
* Copyright 2006 Develer S.r.l. (http://www.develer.com/)
*
* -->
*
* \brief Simple notifier for the subject/observer pattern (interface)
*
* \author Bernie Innocenti <bernie@codewiz.org>
*/
#ifndef MWARE_OBSERVER_H
#define MWARE_OBSERVER_H
#include <struct/list.h>
/**
*
* Here's a simple example:
*
* \code
* Subject kbd_driver;
*
* Observer kbd_observer;
*
* void key_pressed(int event, void *_param)
* {
* char *param = (char *)_param;
*
* if (event == EVENT_KBD_PRESSED)
* printf("You pressed %c\n", *param);
* }
*
* void register_kbd_listener(void)
* {
* observer_SetEvent(&kbd_observer, key_pressed);
* observer_Subscribe(&kbd_driver, &kbd_observer);
* }
* \endcode
*/
typedef struct Observer
{
Node link;
void (*event)(int event_id, void *param);
} Observer;
typedef struct Subject
{
/// Subscribed observers.
List observers;
} Subject;
void observer_SetEvent(Observer *observer, void (*event)(int event_id, void *param));
#define OBSERVER_INITIALIZER(callback) { { NULL, NULL }, callback }
void observer_InitSubject(Subject *subject);
/// Aggiunge un Observer all'insieme
void observer_Subscribe(Subject *subject, Observer *observer);
/// Rimuove un Observer dall'insieme
void observer_Unsubscribe(Subject *subject, Observer *observer);
/// per tutti gli elementi nel set notifica l'evento, chiamando la relativa
/// funzione event
void observer_notify(Subject *subject, int event_id, void *param);
#endif /* MWARE_OBSERVER_H */