/* Test of searching in a string.

   Copyright (C) 2007-2017 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program 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 General Public License for more details.

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

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Written by Bruno Haible <bruno@clisp.org>, 2007.  */

#include <config.h>

#include <string.h>

#include <stdlib.h>

#include "macros.h"

int

main ()

{

  /* This test is executed in the C locale.  */

  {

    const char input[] = "foo";

    const char *result = mbsstr (input, "");

    ASSERT (result == input);

  }

  {

    const char input[] = "foo";

    const char *result = mbsstr (input, "o");

    ASSERT (result == input + 1);

  }

  {

    const char input[] = "ABC ABCDAB ABCDABCDABDE";

    const char *result = mbsstr (input, "ABCDABD");

    ASSERT (result == input + 15);

  }

  {

    const char input[] = "ABC ABCDAB ABCDABCDABDE";

    const char *result = mbsstr (input, "ABCDABE");

    ASSERT (result == NULL);

  }

  /* Check that a very long haystack is handled quickly if the needle is

     short and occurs near the beginning.  */

  {

    size_t repeat = 10000;

    size_t m = 1000000;

    const char *needle =

      "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"

      "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";

    char *haystack = (char *) malloc (m + 1);

    if (haystack != NULL)

      {

        memset (haystack, 'A', m);

        haystack[0] = 'B';

        haystack[m] = '\0';

        for (; repeat > 0; repeat--)

          {

            ASSERT (mbsstr (haystack, needle) == haystack + 1);

          }

        free (haystack);

      }

  }

  /* Check that a very long needle is discarded quickly if the haystack is

     short.  */

  {

    size_t repeat = 10000;

    size_t m = 1000000;

    const char *haystack =

      "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"

      "ABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABAB";

    char *needle = (char *) malloc (m + 1);

    if (needle != NULL)

      {

        memset (needle, 'A', m);

        needle[m] = '\0';

        for (; repeat > 0; repeat--)

          {

            ASSERT (mbsstr (haystack, needle) == NULL);

          }

        free (needle);

      }

  }

  /* Check that the asymptotic worst-case complexity is not quadratic.  */

  {

    size_t m = 1000000;

    char *haystack = (char *) malloc (2 * m + 2);

    char *needle = (char *) malloc (m + 2);

    if (haystack != NULL && needle != NULL)

      {

        const char *result;

        memset (haystack, 'A', 2 * m);

        haystack[2 * m] = 'B';

        haystack[2 * m + 1] = '\0';

        memset (needle, 'A', m);

        needle[m] = 'B';

        needle[m + 1] = '\0';

        result = mbsstr (haystack, needle);

        ASSERT (result == haystack + m);

      }

    free (needle);

    free (haystack);

  }

  return 0;

}