On Tue, Jul 15, 2003 at 04:48:56PM +0200, Leopold Toetsch wrote:
Attached is a test program, showing an implementations for multiple
It didn't arrive. Did you attach it, or did its name end .t ?
No extension was .c. Attachment was there:
$ mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
8CDB611802A 6908 Tue Jul 15 16:48:56 [EMAIL PROTECTED]
(deferred transport)
[EMAIL PROTECTED]
-- 6 Kbytes in 1 Request.
so it must have been stripped elsewhere.
Anyway - renamed to timer_c.txt
Nicholas Clark
leo
/* * itimer test */ #include <sys/time.h> #include <signal.h> #include <stdio.h> #include <malloc.h> #include <math.h>
volatile sig_atomic_t got_alarm = 0;
typedef struct timer_t {
int ticks;
int value;
int repeat;
int run;
int nr;
struct timer_t *next;
struct timer_t *prev;
} timer;
timer *rtimer = 0;
void add_timer(timer *t) {
timer *next = rtimer;
rtimer = t;
t->next = next;
if (next) {
t->nr = next->nr + 1;
next->prev = t;
}
else
t->nr = 1;
}
void del_timer(timer *t) {
timer *next = t->next;
timer *prev = t->prev;
if (prev)
prev->next = next;
else
rtimer = next;
if (next)
next->prev = prev;
free(t);
}
timer * new_timer(void) {
timer *t = calloc(1, sizeof(timer));
add_timer(t);
return t;
}
typedef unsigned int UINTVAL;
typedef double FLOATVAL;
UINTVAL gcd(UINTVAL a, UINTVAL b) {
UINTVAL q = 0;
UINTVAL c = 0;
while (b != 0) {
q = (UINTVAL)floor( (FLOATVAL)a/b );
c = a - b*q;
a = b;
b = c;
}
return a;
}
void
sig_alarm_handler(int i) {
got_alarm = 1;
}
/* platform interface */
void start_sys_timer_ms(void *handle, int ms) {
struct itimerval its;
memset(&its, 0, sizeof(its));
if (ms) {
its.it_interval.tv_sec = its.it_value.tv_sec = ms/1000;
its.it_interval.tv_usec = its.it_value.tv_usec = 1000 *(ms%1000);
}
setitimer(ITIMER_REAL, &its, NULL);
printf("new val = %ld:%ld ms = %d\n",
its.it_value.tv_sec, its.it_value.tv_usec, ms);
}
void stop_sys_timer_ms(void *handle) {
start_sys_timer_ms(handle, 0);
}
int get_sys_timer_ms(void *handle) {
struct itimerval ots;
getitimer(ITIMER_REAL, &ots);
return ots.it_interval.tv_sec * 1000 + ots.it_interval.tv_usec/1000;
}
void * new_sys_timer_ms() {return 0; }
/* end platform interface */
void recalc_ticks(void);
void *handle;
void
do_alarm_handler() {
timer *t;
UINTVAL ms;
int recalc = 0;
ms = get_sys_timer_ms(handle);
for (t = rtimer; t; t= t->next) {
if (!--t->ticks) {
t->run = 1;
if (t->repeat) {
t->ticks = t->value/ms;
if (t->repeat != -1)
t->repeat--;
}
}
}
again:
for (t = rtimer; t; t= t->next) {
if (t->run == 1) {
t->run = 0;
printf("alarm %d\n", t->nr);
/* code run here may add timers, these have t->run = 2 */
goto again;
}
if (!t->ticks && !t->repeat) {
printf("del_timer %d\n", t->nr);
del_timer(t);
recalc = 1;
goto again;
}
}
if (recalc)
recalc_ticks();
}
void p_add_timer(UINTVAL msecs, int repeat)
{
timer *t;
if (!msecs)
return;
t = new_timer();
t->repeat = repeat;
t->value = msecs;
t->run = 2;
recalc_ticks();
}
void p_del_timer(timer *t) {
del_timer(t);
recalc_ticks();
}
void recalc_ticks() {
UINTVAL ms, oms;
timer *t;
oms = get_sys_timer_ms(handle);
printf("gettimer oms = %d\n", oms);
t = rtimer;
if (t) {
t->run = 0;
if (oms && t->ticks)
ms = oms*t->ticks; /* time left */
else
ms = t->value;
if (t->next) {
for (t = t->next; t; t = t->next) {
t->run = 0;
if (oms && t->ticks) {
ms = gcd(oms*t->ticks, ms);
}
else
ms = gcd(t->value, ms);
}
}
printf("new ms %d\n", ms);
again:
for (t = rtimer; t; t= t->next) {
int ot = t->ticks;
printf("t%d oticks %d => ", t->nr, t->ticks);
if (oms && ot)
t->ticks = t->ticks * ((double)oms / (double)ms);
else
t->ticks = t->value / ms;
if (!t->ticks) {
ms = oms;
t->ticks = ot;
goto again;
}
printf("ticks %d value %d\n", t->ticks, t->value);
}
}
else
ms = 0;
if (ms)
start_sys_timer_ms(handle, ms);
else
stop_sys_timer_ms(handle);
}
int main(int argc, char **argv) {
handle = new_sys_timer_ms();
signal(SIGALRM, sig_alarm_handler);
p_add_timer(3000, 1);
p_add_timer(2000, 3);
p_add_timer(500, 1);
while (rtimer) {
if (got_alarm) { /* CHECK_EVENTS */
got_alarm = 0;
do_alarm_handler();
}
}
return 0;
}
