source: branches/minix3-book/servers/fs/timers.c@ 23

/* FS timers library
 */

#include "fs.h"

#include <timers.h>
#include <minix/syslib.h>
#include <minix/com.h>

PRIVATE timer_t *fs_timers = NULL;

PUBLIC void fs_set_timer(timer_t *tp, int ticks, tmr_func_t watchdog, int arg)
{
        int r;
        clock_t now, old_head = 0, new_head;

        if ((r = getuptime(&now)) != OK)
                panic(__FILE__, "FS couldn't get uptime from system task.", NO_NUM);

        tmr_arg(tp)->ta_int = arg;

        old_head = tmrs_settimer(&fs_timers, tp, now+ticks, watchdog, &new_head);

        /* reschedule our synchronous alarm if necessary */
        if (!old_head || old_head > new_head) {
                if (sys_setalarm(new_head, 1) != OK)
                        panic(__FILE__, "FS set timer "
                        "couldn't set synchronous alarm.", NO_NUM);
        }

        return;
}

PUBLIC void fs_expire_timers(clock_t now)
{
        clock_t new_head;
        tmrs_exptimers(&fs_timers, now, &new_head);
        if (new_head > 0) {
                if (sys_setalarm(new_head, 1) != OK)
                        panic(__FILE__, "FS expire timer couldn't set "
                                "synchronous alarm.", NO_NUM);
        }
}

PUBLIC void fs_init_timer(timer_t *tp)
{
        tmr_inittimer(tp);
}

PUBLIC void fs_cancel_timer(timer_t *tp)
{
        clock_t new_head, old_head;
        old_head = tmrs_clrtimer(&fs_timers, tp, &new_head);

        /* if the earliest timer has been removed, we have to set
         * the synalarm to the next timer, or cancel the synalarm
         * altogether if th last time has been cancelled (new_head
         * will be 0 then).
         */
        if (old_head < new_head || !new_head) {
                if (sys_setalarm(new_head, 1) != OK)
                        panic(__FILE__,
                        "FS expire timer couldn't set synchronous alarm.",
                                 NO_NUM);
        }
}