/* alarmtimer suspend test
 *              John Stultz (john.stultz@linaro.org)
 *              (C) Copyright Linaro 2013
 *              Licensed under the GPLv2
 *
 *   This test makes sure the alarmtimer & RTC wakeup code is
 *   functioning.
 *
 *  To build:
 *      $ gcc alarmtimer-suspend.c -o alarmtimer-suspend -lrt
 *
 *   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.
 */


#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <string.h>
#include <signal.h>
#include <stdlib.h>
#include <pthread.h>
#include <include/vdso/time64.h>
#include <errno.h>
#include "kselftest.h"

#define UNREASONABLE_LAT (NSEC_PER_SEC * 5) /* hopefully we resume in 5 secs */

#define SUSPEND_SECS 15
int alarmcount;
int alarm_clock_id;
struct timespec start_time;


char *clockstring(int clockid)
{
        switch (clockid) {
        case CLOCK_REALTIME:
                return "CLOCK_REALTIME";
        case CLOCK_MONOTONIC:
                return "CLOCK_MONOTONIC";
        case CLOCK_PROCESS_CPUTIME_ID:
                return "CLOCK_PROCESS_CPUTIME_ID";
        case CLOCK_THREAD_CPUTIME_ID:
                return "CLOCK_THREAD_CPUTIME_ID";
        case CLOCK_MONOTONIC_RAW:
                return "CLOCK_MONOTONIC_RAW";
        case CLOCK_REALTIME_COARSE:
                return "CLOCK_REALTIME_COARSE";
        case CLOCK_MONOTONIC_COARSE:
                return "CLOCK_MONOTONIC_COARSE";
        case CLOCK_BOOTTIME:
                return "CLOCK_BOOTTIME";
        case CLOCK_REALTIME_ALARM:
                return "CLOCK_REALTIME_ALARM";
        case CLOCK_BOOTTIME_ALARM:
                return "CLOCK_BOOTTIME_ALARM";
        case CLOCK_TAI:
                return "CLOCK_TAI";
        }
        return "UNKNOWN_CLOCKID";
}


long long timespec_sub(struct timespec a, struct timespec b)
{
        long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;

        ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
        return ret;
}

int final_ret;

void sigalarm(int signo)
{
        long long delta_ns;
        struct timespec ts;

        clock_gettime(alarm_clock_id, &ts);
        alarmcount++;

        delta_ns = timespec_sub(start_time, ts);
        delta_ns -= NSEC_PER_SEC * SUSPEND_SECS * alarmcount;

        printf("ALARM(%i): %ld:%ld latency: %lld ns ", alarmcount, ts.tv_sec,
                                                        ts.tv_nsec, delta_ns);

        if (delta_ns > UNREASONABLE_LAT) {
                printf("[FAIL]\n");
                final_ret = -1;
        } else
                printf("[OK]\n");

}

int main(void)
{
        timer_t tm1;
        struct itimerspec its1, its2;
        struct sigevent se;
        struct sigaction act;
        int signum = SIGRTMAX;

        /* Set up signal handler: */
        sigfillset(&act.sa_mask);
        act.sa_flags = 0;
        act.sa_handler = sigalarm;
        sigaction(signum, &act, NULL);

        /* Set up timer: */
        memset(&se, 0, sizeof(se));
        se.sigev_notify = SIGEV_SIGNAL;
        se.sigev_signo = signum;
        se.sigev_value.sival_int = 0;

        for (alarm_clock_id = CLOCK_REALTIME_ALARM;
                        alarm_clock_id <= CLOCK_BOOTTIME_ALARM;
                        alarm_clock_id++) {

                alarmcount = 0;
                if (timer_create(alarm_clock_id, &se, &tm1) == -1) {
                        printf("timer_create failed, %s unsupported?: %s\n",
                                        clockstring(alarm_clock_id), strerror(errno));
                        break;
                }

                clock_gettime(alarm_clock_id, &start_time);
                printf("Start time (%s): %ld:%ld\n", clockstring(alarm_clock_id),
                                start_time.tv_sec, start_time.tv_nsec);
                printf("Setting alarm for every %i seconds\n", SUSPEND_SECS);
                its1.it_value = start_time;
                its1.it_value.tv_sec += SUSPEND_SECS;
                its1.it_interval.tv_sec = SUSPEND_SECS;
                its1.it_interval.tv_nsec = 0;

                timer_settime(tm1, TIMER_ABSTIME, &its1, &its2);

                while (alarmcount < 5)
                        sleep(1); /* First 5 alarms, do nothing */

                printf("Starting suspend loops\n");
                while (alarmcount < 10) {
                        int ret;

                        sleep(3);
                        ret = system("echo mem > /sys/power/state");
                        if (ret)
                                break;
                }
                timer_delete(tm1);
        }
        if (final_ret)
                ksft_exit_fail();
        ksft_exit_pass();
}