port/sys/timerfd.c

/*
 * This file and its contents are supplied under the terms of the
 * Common Development and Distribution License ("CDDL"), version 1.0.
 * You may only use this file in accordance with the terms of version
 * 1.0 of the CDDL.
 *
 * A full copy of the text of the CDDL should have accompanied this
 * source.  A copy of the CDDL is also available via the Internet at
 * http://www.illumos.org/license/CDDL.
 */

/*
 * Copyright (c) 2015, Joyent, Inc.  All rights reserved.
 */

#include <sys/timerfd.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>

int
timerfd_create(int clockid, int flags)
{
    int oflags = O_RDWR;
    int fd;

    if (flags & ~(TFD_NONBLOCK | TFD_CLOEXEC)) {
        errno = EINVAL;
        return (-1);
    }

    if (flags & TFD_NONBLOCK)
        oflags |= O_NONBLOCK;

    if (flags & TFD_CLOEXEC)
        oflags |= O_CLOEXEC;

    if ((fd = open("/dev/timerfd", oflags)) < 0)
        return (-1);

    if (ioctl(fd, TIMERFDIOC_CREATE, clockid) != 0) {
        (void) close(fd);
        return (-1);
    }

    return (fd);
}

int
timerfd_settime(int fd, int flags, const struct itimerspec *new_value,
    struct itimerspec *old_value)
{
    timerfd_settime_t st;
    int rval;

    if (flags & ~(TFD_TIMER_ABSTIME | TFD_TIMER_CANCEL_ON_SET)) {
        errno = EINVAL;
        return (-1);
    }

    st.tfd_settime_flags = flags;
    st.tfd_settime_value = (uint64_t)(uintptr_t)new_value;
    st.tfd_settime_ovalue = (uint64_t)(uintptr_t)old_value;

    rval = ioctl(fd, TIMERFDIOC_SETTIME, &st);

    if (rval == -1 && errno == ENOTTY) {
        /*
         * Linux has us return EINVAL when the file descriptor is valid
         * but is not a timerfd file descriptor -- and LTP explicitly
         * checks this case.
         */
        errno = EINVAL;
    }

    return (rval);
}

int
timerfd_gettime(int fd, struct itimerspec *curr_value)
{
    int rval = ioctl(fd, TIMERFDIOC_GETTIME, curr_value);

    if (rval == -1 && errno == ENOTTY) {
        /*
         * See comment in timerfd_settime(), above.
         */
        errno = EINVAL;
    }

    return (rval);
}