OpenModem/bertos/dt/dnotifier.h

151 lines
4.3 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 2005 Develer S.r.l. (http://www.develer.com/)
* -->
*
* \brief Notifier obj (interface).
*
* \author Bernie Innocenti <bernie@codewiz.org>
* \author Francesco Sacchi <batt@develer.com>
*/
#ifndef DT_DNOTIFIER_H
#define DT_DNOTIFIER_H
#include <cfg/debug.h>
#include <dt/dtag.h>
#include <struct/list.h>
//Fwd declaretion.
struct DNotifier;
struct DFilter;
typedef void (* update_func_ptr)(struct DNotifier *, dtag_t, dval_t);
typedef void (* update_filter_ptr)(struct DFilter *, dtag_t, dval_t);
/**
* Base object for receive and forward messages.
* It contains an update function used to update itslef and a list to
* notify other DNotifer eventually connected.
*/
typedef struct DNotifier
{
/// Receive new attributes from other notifiers.
update_func_ptr update;
/// List of target notifiers to set new attributes to.
List targets;
} DNotifier;
/**
* Map for messages.
* Used to translate src message to dst message.
*/
typedef struct DFilterMap
{
DTagItem src;
DTagItem dst;
} DFilterMap;
/**
* A filter is an interface between two notifier.
* It can translate messages between them through a map (if it is not null).
*/
typedef struct DFilter
{
/// Allow creating a list of dfilter objects.
Node link;
/// Target of the filter
DNotifier *target;
/// Update function called by the source dnotifier
update_filter_ptr update;
///Map for translating messages for target
const DFilterMap *map;
///Used in debug to prevent inserting this filter in more than one list
DB(uint8_t magic;)
} DFilter;
/// Type for filter-mask checking
typedef unsigned int dfilter_mask_t;
/// Filter init
void filter_init(DFilter *f, const DFilterMap *map, bool masked, DNotifier *source, DNotifier *target);
/// Filter update function without masking capabilities.
void filter_update(DFilter *f, dtag_t tag, dval_t val);
/// Filter update function with masking capabilities.
void filter_mask_update(DFilter *f, dtag_t tag, dval_t val);
/// Notifier init
void notifier_init(DNotifier *n);
/**
* Macro to notify the target object.
*/
INLINE void dnotify(DNotifier *target, dtag_t tag, dval_t val)
{
if (target)
target->update(target, tag, val);
}
/**
* Macro to notify all the targets of \a target object.
*/
INLINE void dnotify_targets(DNotifier *target, dtag_t tag, dval_t val)
{
DFilter *f;
if (!LIST_EMPTY(&target->targets))
FOREACH_NODE(f, &target->targets)
f->update(f, tag, val);
}
/**
* Macro that connect \a src notifier to \a tgt using \a map and passing \a opt for filtering option.
* It declares a static filter to achieve connection and messages translation.
* \note Due its static filter declaration, DCONNECT MUST NOT be used inside loops or in functions called multiple times.
* Failing to do so will lead to unpredictable connections between notifiers.
*/
#define DCONNECT(src, tgt, map, opt) \
do { \
static DFilter _filter_; /* Declare a filter */ \
filter_init(&(_filter_), map, opt, src, tgt); /* Init it. */ \
} while (0)
#endif /* DT_DNOTIFIER_H */