/*
 * 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.
 * Copyright 2025 Oxide Computer Company
 */

/*
 * Implementation of C11 and C23 timespec_*() functions. Note, the standard does
 * not have us return values of errno if there are failures for whatever reason,
 * only zero. At least we don't have to preserve errno though.
 */

#include <time.h>
#include <stdbool.h>

static bool
timespec_base_to_clock(int base, clockid_t *clock)
{
        switch (base) {
        case TIME_UTC:
                *clock = CLOCK_REALTIME;
                break;
        case TIME_MONOTONIC:
                *clock = CLOCK_HIGHRES;
                break;
        case TIME_ACTIVE:
                *clock = CLOCK_PROCESS_CPUTIME_ID;
                break;
        case TIME_THREAD_ACTIVE:
                *clock = CLOCK_THREAD_CPUTIME_ID;
                break;
        case TIME_THREAD_ACTIVE_USR:
                *clock = CLOCK_VIRTUAL;
                break;
        default:
                return (false);
        }

        return (true);
}

int
timespec_get(struct timespec *ts, int base)
{
        clockid_t clock;

        if (!timespec_base_to_clock(base, &clock))
                return (0);

        if (clock_gettime(clock, ts) != 0)
                return (0);

        return (base);
}

int
timespec_getres(struct timespec *ts, int base)
{
        clockid_t clock;

        if (!timespec_base_to_clock(base, &clock))
                return (0);

        if (clock_getres(clock, ts) != 0)
                return (0);

        return (base);
}