openbox/openbox/timer.c
2003-03-21 20:25:34 +00:00

136 lines
3 KiB
C

#include "timer.h"
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
static GTimeVal now;
static GTimeVal ret_wait;
static GSList *timers; /* nearest timer is at the top */
#define NEAREST_TIMEOUT (((Timer*)timers->data)->timeout)
static long timecompare(GTimeVal *a, GTimeVal *b)
{
long r;
if ((r = b->tv_sec - a->tv_sec)) return r;
return b->tv_usec - a->tv_sec;
}
static void insert_timer(Timer *self)
{
GSList *it;
for (it = timers; it != NULL; it = it->next) {
Timer *t = it->data;
if (timecompare(&self->timeout, &t->timeout) <= 0) {
timers = g_slist_insert_before(timers, it, self);
break;
}
}
if (it == NULL) /* didnt fit anywhere in the list */
timers = g_slist_append(timers, self);
}
void timer_startup()
{
g_get_current_time(&now);
timers = NULL;
}
void timer_shutdown()
{
GSList *it;
for (it = timers; it != NULL; it = it->next) {
g_free(it->data);
}
g_slist_free(timers);
timers = NULL;
}
Timer *timer_start(long delay, TimeoutHandler cb, void *data)
{
Timer *self = g_new(Timer, 1);
self->delay = delay;
self->action = cb;
self->data = data;
self->del_me = FALSE;
self->last = self->timeout = now;
g_time_val_add(&self->timeout, delay);
insert_timer(self);
return self;
}
void timer_stop(Timer *self)
{
self->del_me = TRUE;
}
/* find the time to wait for the nearest timeout */
static gboolean nearest_timeout_wait(GTimeVal *tm)
{
if (timers == NULL)
return FALSE;
tm->tv_sec = NEAREST_TIMEOUT.tv_sec - now.tv_sec;
tm->tv_usec = NEAREST_TIMEOUT.tv_usec - now.tv_usec;
while (tm->tv_usec < 0) {
tm->tv_usec += G_USEC_PER_SEC;
tm->tv_sec--;
}
tm->tv_sec += tm->tv_usec / G_USEC_PER_SEC;
tm->tv_usec %= G_USEC_PER_SEC;
if (tm->tv_sec < 0)
tm->tv_sec = 0;
return TRUE;
}
void timer_dispatch(GTimeVal **wait)
{
g_get_current_time(&now);
while (timers != NULL) {
Timer *curr = timers->data; /* get the top element */
/* since timer_stop doesn't actually free the timer, we have to do our
real freeing in here.
*/
if (curr->del_me) {
timers = g_slist_delete_link(timers, timers); /* delete the top */
g_free(curr);
continue;
}
/* the queue is sorted, so if this timer shouldn't fire, none are
ready */
if (timecompare(&now, &NEAREST_TIMEOUT) <= 0)
break;
/* we set the last fired time to delay msec after the previous firing,
then re-insert. timers maintain their order and may trigger more
than once if they've waited more than one delay's worth of time.
*/
timers = g_slist_delete_link(timers, timers);
g_time_val_add(&curr->last, curr->delay);
curr->action(curr->data);
g_time_val_add(&curr->timeout, curr->delay);
insert_timer(curr);
/* if at least one timer fires, then don't wait on X events, as there
may already be some in the queue from the timer callbacks.
*/
ret_wait.tv_sec = ret_wait.tv_usec = 0;
*wait = &ret_wait;
return;
}
if (nearest_timeout_wait(&ret_wait))
*wait = &ret_wait;
else
*wait = NULL;
}