/* Test for the memfd_create system call.

   Copyright (C) 2017-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

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

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <errno.h>

#include <fcntl.h>

#include <stdbool.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <support/check.h>

#include <support/support.h>

#include <support/test-driver.h>

#include <support/xunistd.h>

#include <sys/mman.h>

/* Return true if the descriptor has the FD_CLOEXEC flag set.  */

static bool

is_cloexec (int fd)

{

  int flags = fcntl (fd, F_GETFD);

  TEST_VERIFY (flags >= 0);

  return flags & FD_CLOEXEC;

}

/* Return the seals set on FD.  */

static int

get_seals (int fd)

{

  int flags = fcntl (fd, F_GET_SEALS);

  TEST_VERIFY (flags >= 0);

  return flags;

}

/* Return true if the F_SEAL_SEAL flag is set on the descriptor.  */

static bool

is_sealed (int fd)

{

  return get_seals (fd) & F_SEAL_SEAL;

}

static int

do_test (void)

{

  /* Initialized by the first call to memfd_create to 0 (memfd_create

     unsupported) or 1 (memfd_create is implemented in the kernel).

     Subsequent iterations check that the success/failure state is

     consistent.  */

  int supported = -1;

  for (int do_cloexec = 0; do_cloexec < 2; ++do_cloexec)

    for (int do_sealing = 0; do_sealing < 2; ++do_sealing)

      {

        int flags = 0;

        if (do_cloexec)

          flags |= MFD_CLOEXEC;

        if (do_sealing)

          flags |= MFD_ALLOW_SEALING;

        if  (test_verbose > 0)

          printf ("info: memfd_create with flags=0x%x\n", flags);

        int fd = memfd_create ("tst-memfd_create", flags);

        if (fd < 0)

          {

            if (errno == ENOSYS)

              {

                if (supported < 0)

                  {

                    printf ("warning: memfd_create is unsupported\n");

                    supported = 0;

                    continue;

                  }

                TEST_VERIFY (supported == 0);

                continue;

              }

            else

              FAIL_EXIT1 ("memfd_create: %m");

          }

        if (supported < 0)

          supported = 1;

        TEST_VERIFY (supported > 0);

        char *fd_path = xasprintf ("/proc/self/fd/%d", fd);

        char *link = xreadlink (fd_path);

        if (test_verbose > 0)

          printf ("info: memfd link: %s\n", link);

        TEST_VERIFY (strcmp (link, "memfd:tst-memfd_create (deleted)"));

        TEST_VERIFY (is_cloexec (fd) == do_cloexec);

        TEST_VERIFY (is_sealed (fd) == !do_sealing);

        if (do_sealing)

          {

            TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_WRITE) == 0);

            TEST_VERIFY (!is_sealed (fd));

            TEST_VERIFY (get_seals (fd) & F_SEAL_WRITE);

            TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_SEAL) == 0);

            TEST_VERIFY (is_sealed (fd));

          }

        xclose (fd);

        free (fd_path);

        free (link);

      }

  if (supported == 0)

    return EXIT_UNSUPPORTED;

  return 0;

}

#include <support/test-driver.c>