/* Common definitions for pread and pwrite.

   Copyright (C) 2016-2018 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 <error.h>

#include <string.h>

#include <unistd.h>

#include <sys/stat.h>

static void do_prepare (void);

#define PREPARE(argc, argv)	do_prepare ()

static int do_test (void);

#define TEST_FUNCTION		do_test ()

/* We might need a bit longer timeout.  */

#define TIMEOUT 20 /* sec */

/* This defines the `main' function and some more.  */

#include <test-skeleton.c>

/* These are for the temporary file we generate.  */

static char *name;

static int fd;

static void

do_prepare (void)

{

  fd = create_temp_file ("tst-preadwrite.", &name);

  if (fd == -1)

    error (EXIT_FAILURE, errno, "cannot create temporary file");

}

static ssize_t

do_test_with_offset (off_t offset)

{

  char buf[1000];

  char res[1000];

  int i;

  ssize_t ret;

  memset (buf, '\0', sizeof (buf));

  memset (res, '\xff', sizeof (res));

  if (write (fd, buf, sizeof (buf)) != sizeof (buf))

    error (EXIT_FAILURE, errno, "during write");

  for (i = 100; i < 200; ++i)

    buf[i] = i;

  ret = pwrite (fd, buf + 100, 100, offset + 100);

  if (ret == -1)

    error (EXIT_FAILURE, errno, "during pwrite");

  for (i = 450; i < 600; ++i)

    buf[i] = i;

  ret = pwrite (fd, buf + 450, 150, offset + 450);

  if (ret == -1)

    error (EXIT_FAILURE, errno, "during pwrite");

  ret = pread (fd, res, sizeof (buf) - 50, offset + 50);

  if (ret == -1)

    error (EXIT_FAILURE, errno, "during pread");

  if (memcmp (buf + 50, res, ret) != 0)

    {

      printf ("error: read of pread != write of pwrite\n");

      return -1;

    }

  return ret;

}