/* Test of nanosleep() function.

   Copyright (C) 2009-2019 Free Software Foundation, Inc.

   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 3 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.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

/* Written by Eric Blake <ebb9@byu.net>, 2009.  */

#include <config.h>

#include <time.h>

#include "signature.h"

SIGNATURE_CHECK (nanosleep, int, (struct timespec const *, struct timespec *));

#include <errno.h>

#include <signal.h>

#include <unistd.h>

#include "macros.h"

#if HAVE_DECL_ALARM

static void

handle_alarm (int sig)

{

  if (sig != SIGALRM)

    _exit (1);

}

#endif

int

main (void)

{

  struct timespec ts;

  ts.tv_sec = 1000;

  ts.tv_nsec = -1;

  errno = 0;

  ASSERT (nanosleep (&ts, NULL) == -1);

  ASSERT (errno == EINVAL);

  ts.tv_nsec = 1000000000;

  errno = 0;

  ASSERT (nanosleep (&ts, NULL) == -1);

  ASSERT (errno == EINVAL);

  ts.tv_sec = 0;

  ts.tv_nsec = 1;

  ASSERT (nanosleep (&ts, &ts) == 0);

  /* Remaining time is only defined on EINTR failure; but on success,

     it is typically either 0 or unchanged from input.  At any rate,

     it shouldn't be randomly changed to unrelated values.  */

  ASSERT (ts.tv_sec == 0);

  ASSERT (ts.tv_nsec == 0 || ts.tv_nsec == 1);

  ts.tv_nsec = 0;

  ASSERT (nanosleep (&ts, NULL) == 0);

#if HAVE_DECL_ALARM

  {

    const time_t pentecost = 50 * 24 * 60 * 60; /* 50 days.  */

    signal (SIGALRM, handle_alarm);

    alarm (1);

    ts.tv_sec = pentecost;

    ts.tv_nsec = 999999999;

    errno = 0;

    ASSERT (nanosleep (&ts, &ts) == -1);

    ASSERT (errno == EINTR);

    ASSERT (pentecost - 10 < ts.tv_sec && ts.tv_sec <= pentecost);

    ASSERT (0 <= ts.tv_nsec && ts.tv_nsec <= 999999999);

  }

#endif

  return 0;

}