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/*
* (C) 2008,2009 by Holger Hans Peter Freyther <zecke@selfish.org>
* All Rights Reserved
*
* This program 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <assert.h>
#include <string.h>
#include <osmocom/core/timer.h>
static LLIST_HEAD(timer_list);
static struct timeval s_nearest_time;
static struct timeval s_select_time;
#define MICRO_SECONDS 1000000LL
#define TIME_SMALLER(left, right) \
(left.tv_sec*MICRO_SECONDS+left.tv_usec) <= (right.tv_sec*MICRO_SECONDS+right.tv_usec)
void osmo_timer_add(struct osmo_timer_list *timer)
{
struct osmo_timer_list *list_timer;
/* TODO: Optimize and remember the closest item... */
timer->active = 1;
/* this might be called from within update_timers */
llist_for_each_entry(list_timer, &timer_list, entry)
if (timer == list_timer)
return;
timer->in_list = 1;
llist_add(&timer->entry, &timer_list);
}
void
osmo_timer_schedule(struct osmo_timer_list *timer, int seconds, int microseconds)
{
struct timeval current_time;
gettimeofday(¤t_time, NULL);
unsigned long long currentTime = current_time.tv_sec * MICRO_SECONDS + current_time.tv_usec;
currentTime += seconds * MICRO_SECONDS + microseconds;
timer->timeout.tv_sec = currentTime / MICRO_SECONDS;
timer->timeout.tv_usec = currentTime % MICRO_SECONDS;
osmo_timer_add(timer);
}
void osmo_timer_del(struct osmo_timer_list *timer)
{
if (timer->in_list) {
timer->active = 0;
timer->in_list = 0;
llist_del(&timer->entry);
}
}
int osmo_timer_pending(struct osmo_timer_list *timer)
{
return timer->active;
}
/*
* if we have a nearest time return the delta between the current
* time and the time of the nearest timer.
* If the nearest timer timed out return NULL and then we will
* dispatch everything after the select
*/
struct timeval *osmo_timers_nearest(void)
{
struct timeval current_time;
if (s_nearest_time.tv_sec == 0 && s_nearest_time.tv_usec == 0)
return NULL;
if (gettimeofday(¤t_time, NULL) == -1)
return NULL;
unsigned long long nearestTime = s_nearest_time.tv_sec * MICRO_SECONDS + s_nearest_time.tv_usec;
unsigned long long currentTime = current_time.tv_sec * MICRO_SECONDS + current_time.tv_usec;
if (nearestTime < currentTime) {
s_select_time.tv_sec = 0;
s_select_time.tv_usec = 0;
} else {
s_select_time.tv_sec = (nearestTime - currentTime) / MICRO_SECONDS;
s_select_time.tv_usec = (nearestTime - currentTime) % MICRO_SECONDS;
}
return &s_select_time;
}
/*
* Find the nearest time and update s_nearest_time
*/
void osmo_timers_prepare(void)
{
struct osmo_timer_list *timer, *nearest_timer = NULL;
llist_for_each_entry(timer, &timer_list, entry) {
if (!nearest_timer || TIME_SMALLER(timer->timeout, nearest_timer->timeout)) {
nearest_timer = timer;
}
}
if (nearest_timer) {
s_nearest_time = nearest_timer->timeout;
} else {
memset(&s_nearest_time, 0, sizeof(struct timeval));
}
}
/*
* fire all timers... and remove them
*/
int osmo_timers_update(void)
{
struct timeval current_time;
struct osmo_timer_list *timer, *tmp;
int work = 0;
gettimeofday(¤t_time, NULL);
/*
* The callbacks might mess with our list and in this case
* even llist_for_each_entry_safe is not safe to use. To allow
* del_timer, add_timer, schedule_timer to be called from within
* the callback we jump through some loops.
*
* First we set the handled flag of each active timer to zero,
* then we iterate over the list and execute the callbacks. As the
* list might have been changed (specially the next) from within
* the callback we have to start over again. Once every callback
* is dispatched we will remove the non-active from the list.
*
* TODO: If this is a performance issue we can poison a global
* variable in add_timer and del_timer and only then restart.
*/
llist_for_each_entry(timer, &timer_list, entry) {
timer->handled = 0;
}
restart:
llist_for_each_entry(timer, &timer_list, entry) {
if (!timer->handled && TIME_SMALLER(timer->timeout, current_time)) {
timer->handled = 1;
timer->active = 0;
(*timer->cb)(timer->data);
work = 1;
goto restart;
}
}
llist_for_each_entry_safe(timer, tmp, &timer_list, entry) {
timer->handled = 0;
if (!timer->active) {
osmo_timer_del(timer);
}
}
return work;
}
int osmo_timers_check(void)
{
struct osmo_timer_list *timer;
int i = 0;
llist_for_each_entry(timer, &timer_list, entry) {
i++;
}
return i;
}
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