tests/test-memchr2.c

   1 /*
   2  * Copyright (C) 2008-2024 Free Software Foundation, Inc.
   3  * Written by Eric Blake
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 #include "memchr2.h"
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #include "zerosize-ptr.h"
  26 #include "macros.h"
  27
  28 int
  29 main (void)
  30 {
  31   size_t n = 0x100000;
  32   char *input = malloc (n);
  33   ASSERT (input);
  34
  35   input[0] = 'a';
  36   input[1] = 'b';
  37   memset (input + 2, 'c', 1024);
  38   memset (input + 1026, 'd', n - 1028);
  39   input[n - 2] = 'e';
  40   input[n - 1] = 'a';
  41
  42   /* Basic behavior tests.  */
  43   ASSERT (memchr2 (input, 'a', 'b', n) == input);
  44   ASSERT (memchr2 (input, 'b', 'a', n) == input);
  45
  46   ASSERT (memchr2 (input, 'a', 'b', 0) == NULL);
  47   void *page_boundary = zerosize_ptr ();
  48   if (page_boundary)
  49     ASSERT (memchr2 (page_boundary, 'a', 'b', 0) == NULL);
  50
  51   ASSERT (memchr2 (input, 'b', 'd', n) == input + 1);
  52   ASSERT (memchr2 (input + 2, 'b', 'd', n - 2) == input + 1026);
  53
  54   ASSERT (memchr2 (input, 'd', 'e', n) == input + 1026);
  55   ASSERT (memchr2 (input, 'e', 'd', n) == input + 1026);
  56
  57   ASSERT (memchr2 (input + 1, 'a', 'e', n - 1) == input + n - 2);
  58   ASSERT (memchr2 (input + 1, 'e', 'a', n - 1) == input + n - 2);
  59
  60   ASSERT (memchr2 (input, 'f', 'g', n) == NULL);
  61   ASSERT (memchr2 (input, 'f', '\0', n) == NULL);
  62
  63   ASSERT (memchr2 (input, 'a', 'a', n) == input);
  64   ASSERT (memchr2 (input + 1, 'a', 'a', n - 1) == input + n - 1);
  65   ASSERT (memchr2 (input, 'f', 'f', n) == NULL);
  66
  67   /* Check that a very long haystack is handled quickly if one of the
  68      two bytes is found near the beginning.  */
  69   {
  70     size_t repeat = 10000;
  71     for (; repeat > 0; repeat--)
  72       {
  73         ASSERT (memchr2 (input, 'c', 'e', n) == input + 2);
  74         ASSERT (memchr2 (input, 'e', 'c', n) == input + 2);
  75         ASSERT (memchr2 (input, 'c', '\0', n) == input + 2);
  76         ASSERT (memchr2 (input, '\0', 'c', n) == input + 2);
  77       }
  78   }
  79
  80   /* Alignment tests.  */
  81   {
  82     int i, j;
  83     for (i = 0; i < 32; i++)
  84       {
  85         for (j = 0; j < 256; j++)
  86           input[i + j] = j;
  87         for (j = 0; j < 256; j++)
  88           {
  89             ASSERT (memchr2 (input + i, j, 0xff, 256) == input + i + j);
  90             ASSERT (memchr2 (input + i, 0xff, j, 256) == input + i + j);
  91           }
  92       }
  93   }
  94
  95   free (input);
  96
  97   return test_exit_status;
  98 }