// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <sched.h>

#include <sys/timerfd.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>

#include "log.h"
#include "timens.h"

static int tclock_gettime(clockid_t clockid, struct timespec *now)
{
        if (clockid == CLOCK_BOOTTIME_ALARM)
                clockid = CLOCK_BOOTTIME;
        return clock_gettime(clockid, now);
}

static int run_test(int clockid, struct timespec now)
{
        struct itimerspec new_value;
        long long elapsed;
        int fd, i;

        if (check_skip(clockid))
                return 0;

        if (tclock_gettime(clockid, &now))
                return pr_perror("clock_gettime(%d)", clockid);

        for (i = 0; i < 2; i++) {
                int flags = 0;

                new_value.it_value.tv_sec = 3600;
                new_value.it_value.tv_nsec = 0;
                new_value.it_interval.tv_sec = 1;
                new_value.it_interval.tv_nsec = 0;

                if (i == 1) {
                        new_value.it_value.tv_sec += now.tv_sec;
                        new_value.it_value.tv_nsec += now.tv_nsec;
                }

                fd = timerfd_create(clockid, 0);
                if (fd == -1)
                        return pr_perror("timerfd_create(%d)", clockid);

                if (i == 1)
                        flags |= TFD_TIMER_ABSTIME;

                if (timerfd_settime(fd, flags, &new_value, NULL))
                        return pr_perror("timerfd_settime(%d)", clockid);

                if (timerfd_gettime(fd, &new_value))
                        return pr_perror("timerfd_gettime(%d)", clockid);

                elapsed = new_value.it_value.tv_sec;
                if (llabs(elapsed - 3600) > 60) {
                        ksft_test_result_fail("clockid: %d elapsed: %lld\n",
                                              clockid, elapsed);
                        return 1;
                }

                close(fd);
        }

        ksft_test_result_pass("clockid=%d\n", clockid);

        return 0;
}

int main(int argc, char *argv[])
{
        int ret, status, len, fd;
        char buf[4096];
        pid_t pid;
        struct timespec btime_now, mtime_now;

        ksft_print_header();

        nscheck();

        check_supported_timers();

        ksft_set_plan(3);

        clock_gettime(CLOCK_MONOTONIC, &mtime_now);
        clock_gettime(CLOCK_BOOTTIME, &btime_now);

        if (unshare_timens())
                return 1;

        len = snprintf(buf, sizeof(buf), "%d %d 0\n%d %d 0",
                        CLOCK_MONOTONIC, 70 * 24 * 3600,
                        CLOCK_BOOTTIME, 9 * 24 * 3600);
        fd = open("/proc/self/timens_offsets", O_WRONLY);
        if (fd < 0)
                return pr_perror("/proc/self/timens_offsets");

        if (write(fd, buf, len) != len)
                return pr_perror("/proc/self/timens_offsets");

        close(fd);
        mtime_now.tv_sec += 70 * 24 * 3600;
        btime_now.tv_sec += 9 * 24 * 3600;

        pid = fork();
        if (pid < 0)
                return pr_perror("Unable to fork");
        if (pid == 0) {
                ret = 0;
                ret |= run_test(CLOCK_BOOTTIME, btime_now);
                ret |= run_test(CLOCK_MONOTONIC, mtime_now);
                ret |= run_test(CLOCK_BOOTTIME_ALARM, btime_now);

                if (ret)
                        ksft_exit_fail();
                ksft_exit_pass();
                return ret;
        }

        if (waitpid(pid, &status, 0) != pid)
                return pr_perror("Unable to wait the child process");

        if (WIFEXITED(status))
                return WEXITSTATUS(status);

        return 1;
}