clock.c

来自「rtai-3.1-test3的源代码(Real-Time Application」· C语言 代码 · 共 94 行

/*
 * Written by Gilles Chanteperdrix <[e-mail]>.
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */


#include "pse51/thread.h"

/* Only CLOCK_MONOTONIC is supported for the moment. */

int clock_getres(clockid_t clock_id, struct timespec *res)
{
    if(clock_id != CLOCK_MONOTONIC || !res)
        return EINVAL;

    ticks2timespec(res, 1);

    return 0;
}


int clock_gettime(clockid_t clock_id, struct timespec *tp)
{
    if(clock_id != CLOCK_MONOTONIC || !tp)
        return EINVAL;

    ticks2timespec(tp, xnpod_get_time());

    return 0;    
}


int clock_settime(clockid_t clock_id, const struct timespec *tp)
{
    if(clock_id != CLOCK_MONOTONIC || !tp || tp->tv_nsec > 1000000000)
        return EINVAL;

    xnpod_set_time(timespec2ticks(tp));

    return 0;
}


int clock_nanosleep(clockid_t clock_id, int flags,
                    const struct timespec *rqtp, struct timespec *rmtp)
{
    pthread_t cur;
    xnticks_t start, timeout;

    if(clock_id != CLOCK_MONOTONIC || !rqtp || rqtp->tv_nsec > 1000000000)
        return EINVAL;

    cur = pse51_current_thread();
    start = xnpod_get_time();
    timeout = timespec2ticks(rqtp);

    switch(flags) {
    default:
        return EINVAL;
    case TIMER_ABSTIME:
        timeout-=start;
        break;
    case 0:
        break;
    }

    xnpod_delay(timeout);
    if(xnthread_test_flags(&cur->threadbase, XNTIMEO)) {
        if(flags == 0 && rmtp) {
            xnticks_t passed=xnpod_get_time()-start;
            ticks2timespec(rmtp, passed<timeout?timeout-passed:0);
        }

        return EINTR;
    }

    return 0;
}