/* Common f{truncate} tests definitions.

   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 <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <unistd.h>

static void do_prepare (void);

#define PREPARE(argc, argv)     do_prepare ()

static int do_test (void);

#define TEST_FUNCTION           do_test ()

#include <test-skeleton.c>

static char *temp_filename;

static int temp_fd;

static void

do_prepare (void)

{

  temp_fd = create_temp_file ("tst-trucate.", &temp_filename);

  if (temp_fd == -1)

    {

      printf ("cannot create temporary file: %m\n");

      exit (1);

    }

}

#define FAIL(str) \

  do { printf ("error: %s (line %d)\n", str, __LINE__); return 1; } while (0)

static int

do_test_with_offset (off_t offset)

{

  struct stat st;

  char buf[1000];

  memset (buf, 0xcf, sizeof (buf));

  if (pwrite (temp_fd, buf, sizeof (buf), offset) != sizeof (buf))

    FAIL ("write failed");

  if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + sizeof (buf)))

    FAIL ("initial size wrong");

  if (ftruncate (temp_fd, offset + 800) < 0)

    FAIL ("size reduction with ftruncate failed");

  if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 800))

    FAIL ("size after reduction with ftruncate is incorrect");

  /* The following test covers more than POSIX.  POSIX does not require

     that ftruncate() can increase the file size.  But we are testing

     Unix systems.  */

  if (ftruncate (temp_fd, offset + 1200) < 0)

    FAIL ("size increate with ftruncate failed");

  if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 1200))

    FAIL ("size after increase is incorrect");

  if (truncate (temp_filename, offset + 800) < 0)

    FAIL ("size reduction with truncate failed");

  if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 800))

    FAIL ("size after reduction with truncate incorrect");

  /* The following test covers more than POSIX.  POSIX does not require

     that truncate() can increase the file size.  But we are testing

     Unix systems.  */

  if (truncate (temp_filename, (offset + 1200)) < 0)

    FAIL ("size increase with truncate failed");

  if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 1200))

    FAIL ("size increase with truncate is incorrect");

  return 0;

}