tests/test-memchr2.c

   1 /*
   2  * Copyright (C) 2008-2020 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 /* Calculating void * + int is not portable, so this wrapper converts
  29    to char * to make the tests easier to write.  */
  30 #define MEMCHR2 (char *) memchr2
  31
  32 int
  33 main (void)
  34 {
  35   size_t n = 0x100000;
  36   char *input = malloc (n);
  37   ASSERT (input);
  38
  39   input[0] = 'a';
  40   input[1] = 'b';
  41   memset (input + 2, 'c', 1024);
  42   memset (input + 1026, 'd', n - 1028);
  43   input[n - 2] = 'e';
  44   input[n - 1] = 'a';
  45
  46   /* Basic behavior tests.  */
  47   ASSERT (MEMCHR2 (input, 'a', 'b', n) == input);
  48   ASSERT (MEMCHR2 (input, 'b', 'a', n) == input);
  49
  50   ASSERT (MEMCHR2 (input, 'a', 'b', 0) == NULL);
  51   void *page_boundary = zerosize_ptr ();
  52   if (page_boundary)
  53     ASSERT (MEMCHR2 (page_boundary, 'a', 'b', 0) == NULL);
  54
  55   ASSERT (MEMCHR2 (input, 'b', 'd', n) == input + 1);
  56   ASSERT (MEMCHR2 (input + 2, 'b', 'd', n - 2) == input + 1026);
  57
  58   ASSERT (MEMCHR2 (input, 'd', 'e', n) == input + 1026);
  59   ASSERT (MEMCHR2 (input, 'e', 'd', n) == input + 1026);
  60
  61   ASSERT (MEMCHR2 (input + 1, 'a', 'e', n - 1) == input + n - 2);
  62   ASSERT (MEMCHR2 (input + 1, 'e', 'a', n - 1) == input + n - 2);
  63
  64   ASSERT (MEMCHR2 (input, 'f', 'g', n) == NULL);
  65   ASSERT (MEMCHR2 (input, 'f', '\0', n) == NULL);
  66
  67   ASSERT (MEMCHR2 (input, 'a', 'a', n) == input);
  68   ASSERT (MEMCHR2 (input + 1, 'a', 'a', n - 1) == input + n - 1);
  69   ASSERT (MEMCHR2 (input, 'f', 'f', n) == NULL);
  70
  71   /* Check that a very long haystack is handled quickly if one of the
  72      two bytes is found near the beginning.  */
  73   {
  74     size_t repeat = 10000;
  75     for (; repeat > 0; repeat--)
  76       {
  77         ASSERT (MEMCHR2 (input, 'c', 'e', n) == input + 2);
  78         ASSERT (MEMCHR2 (input, 'e', 'c', n) == input + 2);
  79         ASSERT (MEMCHR2 (input, 'c', '\0', n) == input + 2);
  80         ASSERT (MEMCHR2 (input, '\0', 'c', n) == input + 2);
  81       }
  82   }
  83
  84   /* Alignment tests.  */
  85   {
  86     int i, j;
  87     for (i = 0; i < 32; i++)
  88       {
  89         for (j = 0; j < 256; j++)
  90           input[i + j] = j;
  91         for (j = 0; j < 256; j++)
  92           {
  93             ASSERT (MEMCHR2 (input + i, j, 0xff, 256) == input + i + j);
  94             ASSERT (MEMCHR2 (input + i, 0xff, j, 256) == input + i + j);
  95           }
  96       }
  97   }
  98
  99   free (input);
 100
 101   return 0;
 102 }