1  /* Test of uN_strncat() functions.
       2     Copyright (C) 2010-2023 Free Software Foundation, Inc.
       3  
       4     This program is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU General Public License as published by
       6     the Free Software Foundation, either version 3 of the License, or
       7     (at your option) any later version.
       8  
       9     This program is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Written by Bruno Haible <bruno@clisp.org>, 2010.  */
      18  
      19  static void
      20  check_single (const UNIT *input, size_t length, size_t n)
      21  {
      22    static const UNIT base[] = { 'C', 'h', 'a', 'n', 'g', 'i', 'n', 'g', 0 };
      23    size_t m;
      24  
      25    for (m = 0; m < SIZEOF (base); m++)
      26      {
      27        UNIT *dest;
      28        UNIT *result;
      29        size_t i;
      30  
      31        dest = (UNIT *) malloc ((1 + m + n + 2) * sizeof (UNIT));
      32        ASSERT (dest != NULL);
      33  
      34        dest[0] = MAGIC;
      35        for (i = 0; i < m; i++)
      36          dest[1 + i] = base[i];
      37        dest[1 + m] = 0;
      38        for (i = 1; i < n + 2; i++)
      39          dest[1 + m + i] = MAGIC;
      40  
      41        result = U_STRNCAT (dest + 1, input, n);
      42        ASSERT (result == dest + 1);
      43  
      44        ASSERT (dest[0] == MAGIC);
      45        for (i = 0; i < m; i++)
      46          ASSERT (dest[1 + i] == base[i]);
      47        for (i = 0; i < (n <= length ? n : length); i++)
      48          ASSERT (dest[1 + m + i] == input[i]);
      49        ASSERT (dest[1 + m + i] == 0);
      50        ASSERT (dest[1 + m + i + 1] == MAGIC);
      51  
      52        free (dest);
      53      }
      54  }
      55  
      56  static void
      57  check (const UNIT *input, size_t input_length)
      58  {
      59    size_t length;
      60    size_t n;
      61  
      62    ASSERT (input_length > 0);
      63    ASSERT (input[input_length - 1] == 0);
      64    length = input_length - 1; /* = U_STRLEN (input) */
      65  
      66    for (n = 0; n <= 2 * length + 2; n++)
      67      check_single (input, length, n);
      68  
      69    /* Check that U_STRNCAT (D, S, N) does not look at more than
      70       MIN (U_STRLEN (S) + 1, N) units.  */
      71    {
      72      char *page_boundary = (char *) zerosize_ptr ();
      73  
      74      if (page_boundary != NULL)
      75        {
      76          for (n = 0; n <= 2 * length + 2; n++)
      77            {
      78              size_t n_to_copy = (n <= length ? n : length + 1);
      79              UNIT *copy;
      80              size_t i;
      81  
      82              copy = (UNIT *) page_boundary - n_to_copy;
      83              for (i = 0; i < n_to_copy; i++)
      84                copy[i] = input[i];
      85  
      86              check_single (copy, length, n);
      87            }
      88        }
      89    }
      90  }