/* $NetBSD: t_sleep.c,v 1.14 2025/04/08 01:29:08 riastradh Exp $ */

/*-
 * Copyright (c) 2006 Frank Kardel
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#include <sys/event.h>
#include <sys/signal.h>
#include <sys/time.h>           /* for TIMESPEC_TO_TIMEVAL on FreeBSD */

#include <atf-c.h>
#include <errno.h>
#include <inttypes.h>
#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "isqemu.h"

#define BILLION         1000000000LL    /* nano-seconds per second */
#define MILLION         1000000LL       /* nano-seconds per milli-second */

#define ALARM           6               /* SIGALRM after this many seconds */
#define MAXSLEEP        22              /* Maximum delay in seconds */
#define KEVNT_TIMEOUT   10300           /* measured in milli-seconds */
#define FUZZ            (40 * MILLION)  /* scheduling fuzz accepted - 40 ms */

/*
 * Timer notes
 *
 * Most tests use FUZZ as their initial delay value, but 'sleep'
 * starts at 1sec (since it cannot handle sub-second intervals).
 * Subsequent passes double the previous interval, up to MAXSLEEP.
 *
 * The current values result in 5 passes for the 'sleep' test (at 1,
 * 2, 4, 8, and 16 seconds) and 10 passes for the other tests (at
 * 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24, and 20.48
 * seconds).
 *
 * The ALARM is only set if the current pass's delay is longer, and
 * only if the ALARM has not already been triggered.
 *
 * The 'kevent' test needs the ALARM to be set on a different pass
 * from when the KEVNT_TIMEOUT fires.  So set ALARM to fire on the
 * penultimate pass, and the KEVNT_TIMEOUT on the final pass.  We
 * set KEVNT_TIMEOUT just barely long enough to put it into the
 * last test pass, and set MAXSLEEP a couple seconds longer than
 * necessary, in order to avoid a QEMU bug which nearly doubles
 * some timers.
 */

static volatile int sig;

int sleeptest(int (*)(struct timespec *, struct timespec *), bool, bool);
int do_nanosleep(struct timespec *, struct timespec *);
int do_select(struct timespec *, struct timespec *);
int do_poll(struct timespec *, struct timespec *);
int do_sleep(struct timespec *, struct timespec *);
int do_kevent(struct timespec *, struct timespec *);
void sigalrm(int);

void
sigalrm(int s)
{

        sig++;
}

int
do_nanosleep(struct timespec *delay, struct timespec *remain)
{
        int ret;

        if (nanosleep(delay, remain) == -1)
                ret = (errno == EINTR ? 0 : errno);
        else
                ret = 0;
        return ret;
}

int
do_select(struct timespec *delay, struct timespec *remain)
{
        int ret;
        struct timeval tv;

        TIMESPEC_TO_TIMEVAL(&tv, delay);
        if (select(0, NULL, NULL, NULL, &tv) == -1)
                ret = (errno == EINTR ? 0 : errno);
        else
                ret = 0;
        return ret;
}

int
do_poll(struct timespec *delay, struct timespec *remain)
{
        int ret;
        struct timeval tv;

        TIMESPEC_TO_TIMEVAL(&tv, delay);
        if (pollts(NULL, 0, delay, NULL) == -1)
                ret = (errno == EINTR ? 0 : errno);
        else
                ret = 0;
        return ret;
}

int
do_sleep(struct timespec *delay, struct timespec *remain)
{
        struct timeval tv;

        TIMESPEC_TO_TIMEVAL(&tv, delay);
        remain->tv_sec = sleep(delay->tv_sec);
        remain->tv_nsec = 0;

        return 0;
}

int
do_kevent(struct timespec *delay, struct timespec *remain)
{
        struct kevent ktimer;
        struct kevent kresult;
        int rtc, kq, kerrno;
        int tmo;

        ATF_REQUIRE_MSG((kq = kqueue()) != -1, "kqueue: %s", strerror(errno));

        tmo = KEVNT_TIMEOUT;

        /*
         * If we expect the KEVNT_TIMEOUT to fire, and we're running
         * under QEMU, make sure the delay is long enough to account
         * for the effects of PR kern/43997 !
         */
        if (isQEMU() &&
            tmo/1000 < delay->tv_sec && tmo/500 > delay->tv_sec)
                delay->tv_sec = MAXSLEEP;

        fprintf(stderr, "kevent: set EVFILT_TIMER tmo=%d\n", tmo);
        EV_SET(&ktimer, 1, EVFILT_TIMER, EV_ADD, 0, tmo, 0);

        fprintf(stderr, "kevent: wait up to %lld.%09ld sec\n",
            (long long)delay->tv_sec, (long)delay->tv_nsec);
        rtc = kevent(kq, &ktimer, 1, &kresult, 1, delay);
        kerrno = errno;
        fprintf(stderr, "kevent returned rtc=%d\n", rtc);

        (void)close(kq);

        if (rtc == -1) {
                ATF_REQUIRE_MSG(kerrno == EINTR, "kevent: %s",
                    strerror(kerrno));
                return 0;
        }

        if (delay->tv_sec * BILLION + delay->tv_nsec > tmo * MILLION)
                ATF_CHECK_MSG(rtc > 0,
                    "kevent: KEVNT_TIMEOUT did not cause EVFILT_TIMER event");

        return 0;
}

ATF_TC(nanosleep);
ATF_TC_HEAD(nanosleep, tc)
{

        atf_tc_set_md_var(tc, "descr", "Test nanosleep(2) timing");
        atf_tc_set_md_var(tc, "timeout", "65");
}

ATF_TC_BODY(nanosleep, tc)
{

        sleeptest(do_nanosleep, true, false);
}

ATF_TC(select);
ATF_TC_HEAD(select, tc)
{

        atf_tc_set_md_var(tc, "descr", "Test select(2) timing");
        atf_tc_set_md_var(tc, "timeout", "65");
}

ATF_TC_BODY(select, tc)
{

        sleeptest(do_select, true, true);
}

ATF_TC(poll);
ATF_TC_HEAD(poll, tc)
{

        atf_tc_set_md_var(tc, "descr", "Test poll(2) timing");
        atf_tc_set_md_var(tc, "timeout", "65");
}

ATF_TC_BODY(poll, tc)
{

        sleeptest(do_poll, true, true);
}

ATF_TC(sleep);
ATF_TC_HEAD(sleep, tc)
{

        atf_tc_set_md_var(tc, "descr", "Test sleep(3) timing");
        atf_tc_set_md_var(tc, "timeout", "65");
}

ATF_TC_BODY(sleep, tc)
{

        sleeptest(do_sleep, false, false);
}

ATF_TC(kevent);
ATF_TC_HEAD(kevent, tc)
{

        atf_tc_set_md_var(tc, "descr", "Test kevent(2) timing");
        atf_tc_set_md_var(tc, "timeout", "65");
}

ATF_TC_BODY(kevent, tc)
{

        sleeptest(do_kevent, true, true);
}

int
sleeptest(int (*test)(struct timespec *, struct timespec *),
           bool subsec, bool sim_remain)
{
        struct timespec tsa, tsb, tslp, tremain;
        int64_t delta1, delta2, delta3, round;

        sig = 0;
        signal(SIGALRM, sigalrm);

        if (subsec) {
                round = 1;
                delta3 = FUZZ;
        } else {
                round = 1000000000;
                delta3 = round;
        }
        fprintf(stderr, "round=%"PRId64" delta3=%"PRId64"\n", round, delta3);

        tslp.tv_sec = delta3 / 1000000000;
        tslp.tv_nsec = delta3 % 1000000000;
        fprintf(stderr, "initial tslp = %lld.%09ld sec\n",
            (long long)tslp.tv_sec, (long)tslp.tv_nsec);

        while (tslp.tv_sec <= MAXSLEEP) {
                fprintf(stderr, "\n");

                /*
                 * disturb sleep by signal on purpose
                 */
                if (tslp.tv_sec > ALARM && sig == 0) {
                        fprintf(stderr, "request alarm after %d sec\n", ALARM);
                        alarm(ALARM);
                }

                fprintf(stderr, "sleep for %lld.%09ld sec\n",
                    (long long)tslp.tv_sec, (long)tslp.tv_nsec);

                clock_gettime(CLOCK_REALTIME, &tsa);
                (*test)(&tslp, &tremain);
                clock_gettime(CLOCK_REALTIME, &tsb);

                fprintf(stderr, "slept from %lld.%09ld to %lld.%09ld\n",
                    (long long)tsa.tv_sec, (long)tsa.tv_nsec,
                    (long long)tsb.tv_sec, (long)tsb.tv_nsec);

                if (sim_remain) {
                        timespecsub(&tsb, &tsa, &tremain);
                        fprintf(stderr, "slept %lld.%09ld sec\n",
                            (long long)tremain.tv_sec, (long)tremain.tv_nsec);
                        timespecsub(&tslp, &tremain, &tremain);
                }

                fprintf(stderr, "remaining %lld.%09ld sec\n",
                    (long long)tremain.tv_sec, (long)tremain.tv_nsec);

                delta1 = (int64_t)tsb.tv_sec - (int64_t)tsa.tv_sec;
                delta1 *= BILLION;
                delta1 += (int64_t)tsb.tv_nsec - (int64_t)tsa.tv_nsec;

                fprintf(stderr, "delta1=%"PRId64"\n", delta1);

                delta2 = (int64_t)tremain.tv_sec * BILLION;
                delta2 += (int64_t)tremain.tv_nsec;

                fprintf(stderr, "delta2=%"PRId64"\n", delta2);

                delta3 = (int64_t)tslp.tv_sec * BILLION;
                delta3 += (int64_t)tslp.tv_nsec - delta1 - delta2;

                fprintf(stderr, "delta3=%"PRId64"\n", delta3);

                delta3 /= round;
                delta3 *= round;

                fprintf(stderr, "     ->%"PRId64"\n", delta3);

                if (delta3 > FUZZ || delta3 < -FUZZ) {
                        if (!sim_remain)
                                atf_tc_expect_fail("Long reschedule latency "
                                    "due to PR kern/43997");

                        atf_tc_fail("Reschedule latency %"PRId64" exceeds "
                            "allowable fuzz %lld", delta3, FUZZ);
                }
                delta3 = (int64_t)tslp.tv_sec * 2 * BILLION;
                delta3 += (int64_t)tslp.tv_nsec * 2;

                fprintf(stderr, "delta3=%"PRId64"\n", delta3);

                delta3 /= round;
                delta3 *= round;
                fprintf(stderr, "     ->%"PRId64"\n", delta3);
                if (delta3 < FUZZ)
                        break;
                tslp.tv_sec = delta3 / BILLION;
                tslp.tv_nsec = delta3 % BILLION;
                fprintf(stderr, "tslp = %lld.%ld sec\n",
                    (long long)tslp.tv_sec, (long)tslp.tv_nsec);
        }
        ATF_REQUIRE_MSG(sig == 1, "Alarm did not fire!");

        atf_tc_pass();
}

ATF_TP_ADD_TCS(tp)
{
        ATF_TP_ADD_TC(tp, nanosleep);
        ATF_TP_ADD_TC(tp, select);
        ATF_TP_ADD_TC(tp, poll);
        ATF_TP_ADD_TC(tp, sleep);
        ATF_TP_ADD_TC(tp, kevent);

        return atf_no_error();
}