libpri/prisched.c

/*
 * libpri: An implementation of Primary Rate ISDN
 *
 * Written by Mark Spencer <markster@digium.com>
 *
 * Copyright (C) 2001-2005, Digium, Inc.
 * All Rights Reserved.
 */

/*
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2 as published by the
 * Free Software Foundation. See the LICENSE file included with
 * this program for more details.
 *
 * In addition, when this program is distributed with Asterisk in
 * any form that would qualify as a 'combined work' or as a
 * 'derivative work' (but not mere aggregation), you can redistribute
 * and/or modify the combination under the terms of the license
 * provided with that copy of Asterisk, instead of the license
 * terms granted here.
 */

#include <stdio.h>

#include "libpri.h"
#include "pri_internal.h"


static int maxsched = 0;

/* Scheduler routines */
int pri_schedule_event(struct pri *pri, int ms, void (*function)(void *data), void *data)
{
	int x;
	struct timeval tv;
	/* Scheduling runs on master channels only */
	while (pri->master)
		pri = pri->master;
	for (x=1;x<MAX_SCHED;x++)
		if (!pri->pri_sched[x].callback)
			break;
	if (x == MAX_SCHED) {
		pri_error(pri, "No more room in scheduler\n");
		return -1;
	}
	if (x > maxsched)
		maxsched = x;
	gettimeofday(&tv, NULL);
	tv.tv_sec += ms / 1000;
	tv.tv_usec += (ms % 1000) * 1000;
	if (tv.tv_usec > 1000000) {
		tv.tv_usec -= 1000000;
		tv.tv_sec += 1;
	}
	pri->pri_sched[x].when = tv;
	pri->pri_sched[x].callback = function;
	pri->pri_sched[x].data = data;
	return x;
}

struct timeval *pri_schedule_next(struct pri *pri)
{
	struct timeval *closest = NULL;
	int x;
	/* Check subchannels */
	if (pri->subchannel)
		closest = pri_schedule_next(pri->subchannel);
	for (x=1;x<MAX_SCHED;x++) {
		if (pri->pri_sched[x].callback && 
			(!closest || (closest->tv_sec > pri->pri_sched[x].when.tv_sec) ||
				((closest->tv_sec == pri->pri_sched[x].when.tv_sec) && 
				 (closest->tv_usec > pri->pri_sched[x].when.tv_usec))))
				 	closest = &pri->pri_sched[x].when;
	}
	return closest;
}

static pri_event *__pri_schedule_run(struct pri *pri, struct timeval *tv)
{
	int x;
	void (*callback)(void *);
	void *data;
	pri_event *e;
	if (pri->subchannel) {
		if ((e = __pri_schedule_run(pri->subchannel, tv))) {
			return e;
		}
	}
	for (x=1;x<MAX_SCHED;x++) {
		if (pri->pri_sched[x].callback &&
			((pri->pri_sched[x].when.tv_sec < tv->tv_sec) ||
			 ((pri->pri_sched[x].when.tv_sec == tv->tv_sec) &&
			  (pri->pri_sched[x].when.tv_usec <= tv->tv_usec)))) {
			        pri->schedev = 0;
			  	callback = pri->pri_sched[x].callback;
				data = pri->pri_sched[x].data;
				pri->pri_sched[x].callback = NULL;
				pri->pri_sched[x].data = NULL;
				callback(data);
            if (pri->schedev)
                  return &pri->ev;
	    }
	}
	return NULL;
}

pri_event *pri_schedule_run(struct pri *pri)
{
	struct timeval tv;
	gettimeofday(&tv, NULL);
	return __pri_schedule_run(pri, &tv);
}


void pri_schedule_del(struct pri *pri,int id)
{
	while (pri->master)
		pri = pri->master;
	if ((id >= MAX_SCHED) || (id < 0)) 
		pri_error(pri, "Asked to delete sched id %d???\n", id);
	pri->pri_sched[id].callback = NULL;
}