/* fmemopen tests.

   Copyright (C) 2015-2018 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 <assert.h>

#include <stdio.h>

#include <string.h>

#include <sys/types.h>

#include <stdint.h>

#include <errno.h>

/* Check fmemopen with user provided buffer open for write.  */

static int

do_test_with_buffer (void)

{

  int result = 0;

  char buf[100];

  const size_t nbuf = sizeof (buf);

  FILE *fp = fmemopen (buf, nbuf, "w");

  if (fp == NULL)

    {

      printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);

      return 1;

    }

  /* Default write operation, check if file position is correct after it.  */

  static const char str[] = "hello world";

  const size_t nstr = sizeof (str) - 1;

  fputs (str, fp);

  off_t o = ftello (fp);

  if (o != nstr)

    {

      printf ("FAIL: first ftello returned %jd, expected %zu\n",

	      (intmax_t)o, nstr);

      result = 1;

    }

  /* Rewind stream and seek tests, the position size should be equal to

     buffer size provided in open function.  */

  rewind (fp);

  o = ftello (fp);

  if (o != 0)

    {

      printf ("FAIL: second ftello returned %jd, expected 0\n",

	      (intmax_t)o);

      result = 1;

    }

  if (fseeko (fp, 0, SEEK_END) != 0)

    {

      printf ("FAIL: fseeko failed\n");

      result = 1;

    }

  o = ftello (fp);

  if (o != nstr)

    {

      printf ("FAIL: third ftello returned %jd, expected %zu\n",

	      (intmax_t)o, nstr);

      result = 1;

    }

  /* Rewind the stream and recheck by using a shorter string.  */

  rewind (fp);

  static const char str2[] = "just hello";

  const size_t nstr2 = sizeof (str2) - 1;

  assert (nstr2 < nstr);

  fputs (str2, fp);

  o = ftello (fp);

  if (o != nstr2)

    {

      printf ("FAIL: fourth ftello returned %jd, expected %zu\n",

	      (intmax_t)o, nstr2);

      result = 1;

    }

  fclose (fp);

  /* Again, but now with a larger string.  */

  static const char str3[] = "just hellod";

  if (strcmp (buf, str3) != 0)

    {

      printf ("FAIL: final string is \"%s\", expected \"%s\"\n",

              buf, str3);

      result = 1;

    }

  return result;

}

/* Check fmemopen without user provided buffer open for write.  */

static int

do_test_without_buffer (void)

{

  int result = 0;

  const size_t nbuf = 100;

  FILE *fp = fmemopen (NULL, nbuf, "w");

  if (fp == NULL)

    {

      printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);

      return 1;

    }

  static const char str[] = "hello world";

  const size_t nstr = sizeof (str) - 1;

  /* Default write operation, check if file position is correct after it.  */

  fputs (str, fp);

  off_t o = ftello (fp);

  if (o != nstr)

    {

      printf ("FAIL: first ftello returned %jd, expected %zu\n",

	      (intmax_t) o, nstr);

      result = 1;

    }

  if (fseeko (fp, 0, SEEK_END) != 0)

    {

      printf ("FAIL: fseeko failed\n");

      result = 1;

    }

  o = ftello (fp);

  if (o != nstr)

    {

      printf ("FAIL: second ftello returned %jd, expected %zu\n",

	      (intmax_t) o, nbuf);

      result = 1;

    }

  /* Rewind the stream and recheck by using a shorter string.  */

  rewind (fp);

  static const char str2[] = "just hello";

  const size_t nstr2 = sizeof (str2) - 1;

  assert (nstr2 < nstr);

  fputs (str2, fp);

  o = ftello (fp);

  if (o != nstr2)

    {

      printf ("FAIL: third ftello returned %jd, expected %zu\n",

	      (intmax_t) o, nstr2);

      result = 1;

    }

  fclose (fp);

  return result;

}

/* Check fmemopen with a buffer lenght of zero.  */

static int

do_test_length_zero (void)

{

  int result = 0;

  FILE *fp;

#define BUFCONTENTS "testing buffer"

  char buf[100] = BUFCONTENTS;

  const size_t nbuf = 0;

  int r;

  fp = fmemopen (buf, nbuf, "r");

  if (fp == NULL)

    {

      printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);

      return 1;

    }

  /* Reading any data on a zero-length buffer should return EOF.  */

  if ((r = fgetc (fp)) != EOF)

    {

      printf ("FAIL: fgetc on a zero-length returned: %d\n", r);

      result = 1;

    }

  off_t o = ftello (fp);

  if (o != 0)

    {

      printf ("FAIL: first ftello returned %jd, expected 0\n",

	      (intmax_t) o);

      result = 1;

    }

  fclose (fp);

  /* Writing any data shall start at current position and shall not pass

     current buffer size beyond the size in fmemopen call.  */

  fp = fmemopen (buf, nbuf, "w");

  if (fp == NULL)

    {

      printf ("FAIL: second fmemopen failed (%s)\n", __FUNCTION__);

      return 1;

    }

  static const char str[] = "hello world";

  /* Because of buffering, the fputs call itself will not fail. However the

     final buffer should be not changed because length 0 was passed to the

     fmemopen call.  */

  fputs (str, fp);

  r = 0;

  errno = 0;

  if (fflush (fp) != EOF)

    {

      printf ("FAIL: fflush did not return EOF\n");

      fclose (fp);

      return 1;

    }

  if (errno != ENOSPC)

    {

      printf ("FAIL: errno is %i (expected ENOSPC)\n", errno);

      fclose (fp);

      return 1;

    }

  fclose (fp);

  if (strcmp (buf, BUFCONTENTS) != 0)

    {

      printf ("FAIL: strcmp (%s, %s) failed\n", buf, BUFCONTENTS);

      return 1;

    }

  /* Different than 'w' mode, 'w+' truncates the buffer.  */

  fp = fmemopen (buf, nbuf, "w+");

  if (fp == NULL)

    {

      printf ("FAIL: third fmemopen failed (%s)\n", __FUNCTION__);

      return 1;

    }

  fclose (fp);

  if (strcmp (buf, "") != 0)

    {

      printf ("FAIL: strcmp (%s, \"\") failed\n", buf);

      return 1;

    }

  return result;

}

static int

do_test (void)

{

  int ret = 0;

  ret += do_test_with_buffer ();

  ret += do_test_without_buffer ();

  ret += do_test_length_zero ();

  return ret;

}

#define TEST_FUNCTION do_test ()

#include "../test-skeleton.c"