string/test-memmem.c

   1 /* Test and measure memmem functions.
   2    Copyright (C) 2008-2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #define TEST_MAIN
  20 #define TEST_NAME "memmem"
  21 #define BUF1PAGES 20
  22 #define ITERATIONS 500
  23 #include "test-string.h"
  24
  25 typedef char *(*proto_t) (const void *, size_t, const void *, size_t);
  26 void *simple_memmem (const void *, size_t, const void *, size_t);
  27
  28 IMPL (simple_memmem, 0)
  29 IMPL (memmem, 1)
  30
  31 void *
  32 simple_memmem (const void *haystack, size_t haystack_len, const void *needle,
  33                size_t needle_len)
  34 {
  35   const char *begin;
  36   const char *const last_possible
  37     = (const char *) haystack + haystack_len - needle_len;
  38
  39   if (needle_len == 0)
  40     /* The first occurrence of the empty string is deemed to occur at
  41        the beginning of the string.  */
  42     return (void *) haystack;
  43
  44   /* Sanity check, otherwise the loop might search through the whole
  45      memory.  */
  46   if (__glibc_unlikely (haystack_len < needle_len))
  47     return NULL;
  48
  49   for (begin = (const char *) haystack; begin <= last_possible; ++begin)
  50     if (begin[0] == ((const char *) needle)[0]
  51         && !memcmp ((const void *) &begin[1],
  52                     (const void *) ((const char *) needle + 1),
  53                     needle_len - 1))
  54       return (void *) begin;
  55
  56   return NULL;
  57 }
  58
  59 static int
  60 check_result (impl_t *impl, const void *haystack, size_t haystack_len,
  61              const void *needle, size_t needle_len, const void *expected)
  62 {
  63   void *res;
  64
  65   res = CALL (impl, haystack, haystack_len, needle, needle_len);
  66   if (res != expected)
  67     {
  68       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  69              res, expected);
  70       ret = 1;
  71       return -1;
  72     }
  73
  74   return 0;
  75 }
  76
  77 static void
  78 do_one_test (impl_t *impl, const void *haystack, size_t haystack_len,
  79              const void *needle, size_t needle_len, const void *expected)
  80 {
  81   if (check_result (impl, haystack, haystack_len, needle, needle_len,
  82                     expected) < 0)
  83     return;
  84 }
  85
  86 static void
  87 do_test (const char *str, size_t len, size_t idx)
  88 {
  89   char tmpbuf[len];
  90
  91   memcpy (tmpbuf, buf1 + idx, len);
  92   memcpy (buf1 + idx, str, len);
  93
  94   FOR_EACH_IMPL (impl, 0)
  95     do_one_test (impl, buf1, BUF1PAGES * page_size, str, len, buf1 + idx);
  96
  97   memcpy (buf1 + idx, tmpbuf, len);
  98 }
  99
 100 static void
 101 do_random_tests (void)
 102 {
 103   for (size_t n = 0; n < ITERATIONS; ++n)
 104     {
 105       char tmpbuf[32];
 106
 107       size_t shift = random () % 11;
 108       size_t rel = random () % ((2 << (shift + 1)) * 64);
 109       size_t idx = MIN ((2 << shift) * 64 + rel, BUF1PAGES * page_size - 2);
 110       size_t len = random () % (sizeof (tmpbuf) - 1) + 1;
 111       len = MIN (len, BUF1PAGES * page_size - idx - 1);
 112       memcpy (tmpbuf, buf1 + idx, len);
 113       for (size_t i = random () % len / 2 + 1; i > 0; --i)
 114         {
 115           size_t off = random () % len;
 116           char ch = '0' + random () % 10;
 117
 118           buf1[idx + off] = ch;
 119         }
 120
 121       FOR_EACH_IMPL (impl, 0)
 122         do_one_test (impl, buf1, BUF1PAGES * page_size, buf1 + idx, len,
 123                      buf1 + idx);
 124
 125       memcpy (buf1 + idx, tmpbuf, len);
 126     }
 127 }
 128
 129 static void
 130 check1 (void)
 131 {
 132
 133   const char search_buf_data[5] = { 0x56, 0x34, 0x12, 0x78, 0x78 };
 134   const char pattern[2] = { 0x78, 0x56 };
 135   void *search_buf = (void *) buf1 + page_size - sizeof search_buf_data;
 136   void *exp_result;
 137
 138   memcpy (search_buf, search_buf_data, sizeof search_buf_data);
 139   exp_result = simple_memmem (search_buf, sizeof search_buf_data,
 140                               pattern, sizeof pattern);
 141   FOR_EACH_IMPL (impl, 0)
 142     check_result (impl, search_buf, sizeof search_buf_data,
 143                   pattern, sizeof pattern, exp_result);
 144 }
 145
 146 static const char *const strs[] =
 147   {
 148     "00000", "00112233", "0123456789", "0000111100001111",
 149     "00000111110000022222", "012345678901234567890",
 150     "abc0", "aaaa0", "abcabc0"
 151   };
 152
 153
 154 int
 155 test_main (void)
 156 {
 157   size_t i;
 158
 159   test_init ();
 160
 161   check1 ();
 162
 163   printf ("%23s", "");
 164   FOR_EACH_IMPL (impl, 0)
 165     printf ("\t%s", impl->name);
 166   putchar ('\n');
 167
 168   for (i = 0; i < BUF1PAGES * page_size; ++i)
 169     buf1[i] = 60 + random () % 32;
 170
 171   for (i = 0; i < sizeof (strs) / sizeof (strs[0]); ++i)
 172     for (size_t j = 0; j < 120; j += 7)
 173       {
 174         size_t len = strlen (strs[i]);
 175
 176         do_test (strs[i], len, j);
 177       }
 178
 179   do_random_tests ();
 180   return ret;
 181 }
 182
 183 #include <support/test-driver.c>