tests/test-memrchr.c

   1 /*
   2  * Copyright (C) 2008-2020 Free Software Foundation, Inc.
   3  * Written by Eric Blake and Bruno Haible
   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 <string.h>
  21
  22 #include "signature.h"
  23 SIGNATURE_CHECK (memrchr, void *, (void const *, int, size_t));
  24
  25 #include <stdlib.h>
  26
  27 #include "zerosize-ptr.h"
  28 #include "macros.h"
  29
  30 /* Calculating void * + int is not portable, so this wrapper converts
  31    to char * to make the tests easier to write.  */
  32 #define MEMRCHR (char *) memrchr
  33
  34 int
  35 main (void)
  36 {
  37   size_t n = 0x100000;
  38   char *input = malloc (n);
  39   ASSERT (input);
  40
  41   input[n - 1] = 'a';
  42   input[n - 2] = 'b';
  43   memset (input + n - 1026, 'c', 1024);
  44   memset (input + 2, 'd', n - 1028);
  45   input[1] = 'e';
  46   input[0] = 'a';
  47
  48   /* Basic behavior tests.  */
  49   ASSERT (MEMRCHR (input, 'a', n) == input + n - 1);
  50
  51   ASSERT (MEMRCHR (input, 'a', 0) == NULL);
  52   void *page_boundary = zerosize_ptr ();
  53   if (page_boundary)
  54     ASSERT (MEMRCHR (page_boundary, 'a', 0) == NULL);
  55
  56   ASSERT (MEMRCHR (input, 'b', n) == input + n - 2);
  57   ASSERT (MEMRCHR (input, 'c', n) == input + n - 3);
  58   ASSERT (MEMRCHR (input, 'd', n) == input + n - 1027);
  59
  60   ASSERT (MEMRCHR (input, 'a', n - 1) == input);
  61   ASSERT (MEMRCHR (input, 'e', n - 1) == input + 1);
  62
  63   ASSERT (MEMRCHR (input, 'f', n) == NULL);
  64   ASSERT (MEMRCHR (input, '\0', n) == NULL);
  65
  66   /* Check that a very long haystack is handled quickly if the byte is
  67      found near the end.  */
  68   {
  69     size_t repeat = 10000;
  70     for (; repeat > 0; repeat--)
  71       {
  72         ASSERT (MEMRCHR (input, 'c', n) == input + n - 3);
  73       }
  74   }
  75
  76   /* Alignment tests.  */
  77   {
  78     int i, j;
  79     for (i = 0; i < 32; i++)
  80       {
  81         for (j = 0; j < 256; j++)
  82           input[i + j] = j;
  83         for (j = 0; j < 256; j++)
  84           {
  85             ASSERT (MEMRCHR (input + i, j, 256) == input + i + j);
  86           }
  87       }
  88   }
  89
  90   free (input);
  91
  92   return 0;
  93 }