freebsd-nq/usr.sbin/rtadvd/timer.c

206 lines
5.2 KiB
C
Raw Normal View History

/* $FreeBSD$ */
/* $KAME: timer.c,v 1.9 2002/06/10 19:59:47 itojun Exp $ */
/*
* Copyright (C) 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/time.h>
#include <sys/queue.h>
#include <unistd.h>
#include <syslog.h>
#include <stdlib.h>
#include <string.h>
#include <search.h>
#include "timer.h"
#define MILLION 1000000
struct rtadvd_timer_head_t ra_timer =
TAILQ_HEAD_INITIALIZER(ra_timer);
static struct timeval tm_limit = {0x7fffffff, 0x7fffffff};
static struct timeval tm_max;
void
rtadvd_timer_init(void)
{
tm_max = tm_limit;
TAILQ_INIT(&ra_timer);
}
struct rtadvd_timer *
2007-11-07 10:53:41 +00:00
rtadvd_add_timer(struct rtadvd_timer *(*timeout)(void *),
void (*update)(void *, struct timeval *),
void *timeodata, void *updatedata)
{
struct rtadvd_timer *rat;
if (timeout == NULL) {
syslog(LOG_ERR,
"<%s> timeout function unspecified", __func__);
exit(1);
}
rat = malloc(sizeof(*rat));
if (rat == NULL) {
syslog(LOG_ERR,
"<%s> can't allocate memory", __func__);
exit(1);
}
memset(rat, 0, sizeof(*rat));
rat->rat_expire = timeout;
rat->rat_update = update;
rat->rat_expire_data = timeodata;
rat->rat_update_data = updatedata;
rat->rat_tm = tm_max;
/* link into chain */
TAILQ_INSERT_TAIL(&ra_timer, rat, rat_next);
return (rat);
}
void
rtadvd_remove_timer(struct rtadvd_timer *rat)
{
if (rat == NULL)
return;
TAILQ_REMOVE(&ra_timer, rat, rat_next);
free(rat);
}
void
rtadvd_set_timer(struct timeval *tm, struct rtadvd_timer *rat)
{
struct timeval now;
/* reset the timer */
gettimeofday(&now, NULL);
TIMEVAL_ADD(&now, tm, &rat->rat_tm);
/* update the next expiration time */
if (TIMEVAL_LT(&rat->rat_tm, &tm_max))
tm_max = rat->rat_tm;
return;
}
/*
* Check expiration for each timer. If a timer expires,
* call the expire function for the timer and update the timer.
* Return the next interval for select() call.
*/
struct timeval *
rtadvd_check_timer(void)
{
static struct timeval returnval;
struct timeval now;
struct rtadvd_timer *rat;
gettimeofday(&now, NULL);
tm_max = tm_limit;
TAILQ_FOREACH(rat, &ra_timer, rat_next) {
if (TIMEVAL_LEQ(&rat->rat_tm, &now)) {
if (((*rat->rat_expire)(rat->rat_expire_data) == NULL))
continue; /* the timer was removed */
if (rat->rat_update)
(*rat->rat_update)(rat->rat_update_data, &rat->rat_tm);
TIMEVAL_ADD(&rat->rat_tm, &now, &rat->rat_tm);
}
if (TIMEVAL_LT(&rat->rat_tm, &tm_max))
tm_max = rat->rat_tm;
}
if (TIMEVAL_EQUAL(&tm_max, &tm_limit)) {
/* no need to timeout */
return (NULL);
} else if (TIMEVAL_LT(&tm_max, &now)) {
/* this may occur when the interval is too small */
returnval.tv_sec = returnval.tv_usec = 0;
} else
TIMEVAL_SUB(&tm_max, &now, &returnval);
return (&returnval);
}
struct timeval *
rtadvd_timer_rest(struct rtadvd_timer *rat)
{
static struct timeval returnval, now;
gettimeofday(&now, NULL);
if (TIMEVAL_LEQ(&rat->rat_tm, &now)) {
syslog(LOG_DEBUG,
"<%s> a timer must be expired, but not yet",
__func__);
returnval.tv_sec = returnval.tv_usec = 0;
}
else
TIMEVAL_SUB(&rat->rat_tm, &now, &returnval);
return (&returnval);
}
/* result = a + b */
void
TIMEVAL_ADD(struct timeval *a, struct timeval *b, struct timeval *result)
{
long l;
if ((l = a->tv_usec + b->tv_usec) < MILLION) {
result->tv_usec = l;
result->tv_sec = a->tv_sec + b->tv_sec;
}
else {
result->tv_usec = l - MILLION;
result->tv_sec = a->tv_sec + b->tv_sec + 1;
}
}
/*
* result = a - b
* XXX: this function assumes that a >= b.
*/
void
TIMEVAL_SUB(struct timeval *a, struct timeval *b, struct timeval *result)
{
long l;
if ((l = a->tv_usec - b->tv_usec) >= 0) {
result->tv_usec = l;
result->tv_sec = a->tv_sec - b->tv_sec;
}
else {
result->tv_usec = MILLION + l;
result->tv_sec = a->tv_sec - b->tv_sec - 1;
}
}