1/*
2 * Copyright (C) 2008-2010 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 <http://www.gnu.org/licenses/>.  */
17
18#include <config.h>
19
20#include <string.h>
21
22#include "signature.h"
23SIGNATURE_CHECK (memchr, 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 MEMCHR (char *) memchr
33
34int
35main (void)
36{
37  size_t n = 0x100000;
38  char *input = malloc (n);
39  ASSERT (input);
40
41  input[0] = 'a';
42  input[1] = 'b';
43  memset (input + 2, 'c', 1024);
44  memset (input + 1026, 'd', n - 1028);
45  input[n - 2] = 'e';
46  input[n - 1] = 'a';
47
48  /* Basic behavior tests.  */
49  ASSERT (MEMCHR (input, 'a', n) == input);
50
51  ASSERT (MEMCHR (input, 'a', 0) == NULL);
52  ASSERT (MEMCHR (zerosize_ptr (), 'a', 0) == NULL);
53
54  ASSERT (MEMCHR (input, 'b', n) == input + 1);
55  ASSERT (MEMCHR (input, 'c', n) == input + 2);
56  ASSERT (MEMCHR (input, 'd', n) == input + 1026);
57
58  ASSERT (MEMCHR (input + 1, 'a', n - 1) == input + n - 1);
59  ASSERT (MEMCHR (input + 1, 'e', n - 1) == input + n - 2);
60
61  ASSERT (MEMCHR (input, 'f', n) == NULL);
62  ASSERT (MEMCHR (input, '\0', n) == NULL);
63
64  /* Check that a very long haystack is handled quickly if the byte is
65     found near the beginning.  */
66  {
67    size_t repeat = 10000;
68    for (; repeat > 0; repeat--)
69      {
70        ASSERT (MEMCHR (input, 'c', n) == input + 2);
71      }
72  }
73
74  /* Alignment tests.  */
75  {
76    int i, j;
77    for (i = 0; i < 32; i++)
78      {
79        for (j = 0; j < 256; j++)
80          input[i + j] = j;
81        for (j = 0; j < 256; j++)
82          {
83            ASSERT (MEMCHR (input + i, j, 256) == input + i + j);
84          }
85      }
86  }
87
88  /* Check that memchr() does not read past the first occurrence of the
89     byte being searched.  See the Austin Group's clarification
90     <http://www.opengroup.org/austin/docs/austin_454.txt>.  */
91  {
92    char *page_boundary = (char *) zerosize_ptr ();
93
94    if (page_boundary != NULL)
95      {
96        for (n = 1; n <= 500; n++)
97          {
98            char *mem = page_boundary - n;
99            memset (mem, 'X', n);
100            ASSERT (MEMCHR (mem, 'U', n) == NULL);
101
102            {
103              size_t i;
104
105              for (i = 0; i < n; i++)
106                {
107                  mem[i] = 'U';
108                  ASSERT (MEMCHR (mem, 'U', 4000) == mem + i);
109                  mem[i] = 'X';
110                }
111            }
112          }
113      }
114  }
115
116  free (input);
117
118  return 0;
119}
120