/* Test and measure memrchr functions.

   Copyright (C) 2013-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Written by Jakub Jelinek <jakub@redhat.com>, 1999.

   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/>.  */

#define TEST_MAIN

#define TEST_NAME "memrchr"

#include "test-string.h"

typedef char *(*proto_t) (const char *, int, size_t);

char *simple_memrchr (const char *, int, size_t);

IMPL (simple_memrchr, 0)

IMPL (memrchr, 1)

char *

simple_memrchr (const char *s, int c, size_t n)

{

  s = s + n;

  while (n--)

    if (*--s == (char) c)

      return (char *) s;

  return NULL;

}

static void

do_one_test (impl_t *impl, const char *s, int c, size_t n, char *exp_res)

{

  char *res = CALL (impl, s, c, n);

  if (res != exp_res)

    {

      error (0, 0, "Wrong result in function %s %p %p", impl->name,

	     res, exp_res);

      ret = 1;

      return;

    }

}

static void

do_test (size_t align, size_t pos, size_t len, int seek_char)

{

  size_t i;

  char *result;

  align &= 7;

  if (align + len >= page_size)

    return;

  for (i = 0; i < len; ++i)

    {

      buf1[align + i] = 1 + 23 * i % 127;

      if (buf1[align + i] == seek_char)

        buf1[align + i] = seek_char + 1;

    }

  buf1[align + len] = 0;

  if (pos < len)

    {

      buf1[align + pos] = seek_char;

      buf1[align + len] = -seek_char;

      result = (char *) (buf1 + align + pos);

    }

  else

    {

      result = NULL;

      buf1[align + len] = seek_char;

    }

  FOR_EACH_IMPL (impl, 0)

    do_one_test (impl, (char *) (buf1 + align), seek_char, len, result);

}

static void

do_random_tests (void)

{

  size_t i, j, n, align, pos, len;

  int seek_char;

  char *result;

  unsigned char *p = buf1 + page_size - 512;

  for (n = 0; n < ITERATIONS; n++)

    {

      align = random () & 15;

      pos = random () & 511;

      if (pos + align >= 512)

	pos = 511 - align - (random () & 7);

      len = random () & 511;

      if (pos >= len)

	len = pos + (random () & 7);

      if (len + align >= 512)

        len = 512 - align - (random () & 7);

      seek_char = random () & 255;

      j = len + align + 64;

      if (j > 512)

        j = 512;

      for (i = 0; i < j; i++)

	{

	  if (i == pos + align)

	    p[i] = seek_char;

	  else

	    {

	      p[i] = random () & 255;

	      if (p[i] == seek_char)

		p[i] = seek_char + 13;

	    }

	}

      if (pos < len)

	result = (char *) (p + pos + align);

      else

	result = NULL;

      FOR_EACH_IMPL (impl, 1)

	if (CALL (impl, (char *) (p + align), seek_char, len) != result)

	  {

	    error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %d, %zd, %zd) %p != %p, p %p",

		   n, impl->name, align, seek_char, len, pos,

		   CALL (impl, (char *) (p + align), seek_char, len),

		   result, p);

	    ret = 1;

	  }

    }

}

int

test_main (void)

{

  size_t i;

  test_init ();

  printf ("%20s", "");

  FOR_EACH_IMPL (impl, 0)

    printf ("\t%s", impl->name);

  putchar ('\n');

  for (i = 1; i < 8; ++i)

    {

      /* Test len == 0.  */

      do_test (i, i, 0, 0);

      do_test (i, i, 0, 23);

      do_test (0, 16 << i, 2048, 23);

      do_test (i, 64, 256, 23);

      do_test (0, 16 << i, 2048, 0);

      do_test (i, 64, 256, 0);

      do_test (0, i, 256, 23);

      do_test (0, i, 256, 0);

      do_test (i, i, 256, 23);

      do_test (i, i, 256, 0);

    }

  for (i = 1; i < 32; ++i)

    {

      do_test (0, i, i + 1, 23);

      do_test (0, i, i + 1, 0);

      do_test (i, i, i + 1, 23);

      do_test (i, i, i + 1, 0);

      do_test (0, 1, i + 1, 23);

      do_test (0, 2, i + 1, 0);

      do_test (i, 1, i + 1, 23);

      do_test (i, 2, i + 1, 0);

    }

  do_random_tests ();

  return ret;

}

#include <support/test-driver.c>