tests/unistr/test-strnlen.h

   1 /* Test of uN_strnlen() functions.
   2    Copyright (C) 2010-2020 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   size_t result = U_STRNLEN (input, n);
  23   ASSERT (result == (n <= length ? n : length));
  24 }
  25
  26 static void
  27 check (const UNIT *input, size_t input_length)
  28 {
  29   size_t length;
  30   size_t n;
  31
  32   ASSERT (input_length > 0);
  33   ASSERT (input[input_length - 1] == 0);
  34   length = input_length - 1; /* = U_STRLEN (input) */
  35
  36   for (n = 0; n <= 2 * length + 2; n++)
  37     check_single (input, length, n);
  38
  39   /* Check that U_STRNLEN (S, N) does not look at more than
  40      MIN (U_STRLEN (S) + 1, N) units.  */
  41   {
  42     char *page_boundary = (char *) zerosize_ptr ();
  43
  44     if (page_boundary != NULL)
  45       {
  46         for (n = 0; n <= 2 * length + 2; n++)
  47           {
  48             size_t n_to_copy = (n <= length ? n : length + 1);
  49             UNIT *copy;
  50             size_t i;
  51
  52             copy = (UNIT *) page_boundary - n_to_copy;
  53             for (i = 0; i < n_to_copy; i++)
  54               copy[i] = input[i];
  55
  56             check_single (copy, length, n);
  57           }
  58       }
  59   }
  60 }