string/test-memmem.c

   1 /* Test and measure memmem functions.
   2    Copyright (C) 2008 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Written by Ulrich Drepper <drepper@redhat.com>, 2008.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #define TEST_MAIN
  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 (__builtin_expect (haystack_len < needle_len, 0))
  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   if (HP_TIMING_AVAIL)
  86     {
  87       hp_timing_t start __attribute ((unused));
  88       hp_timing_t stop __attribute ((unused));
  89       hp_timing_t best_time = ~ (hp_timing_t) 0;
  90       size_t i;
  91
  92       for (i = 0; i < 32; ++i)
  93         {
  94           HP_TIMING_NOW (start);
  95           CALL (impl, haystack, haystack_len, needle, needle_len);
  96           HP_TIMING_NOW (stop);
  97           HP_TIMING_BEST (best_time, start, stop);
  98         }
  99
 100       printf ("\t%zd", (size_t) best_time);
 101     }
 102 }
 103
 104 static void
 105 do_test (const char *str, size_t len, size_t idx)
 106 {
 107   char tmpbuf[len];
 108
 109   memcpy (tmpbuf, buf1 + idx, len);
 110   memcpy (buf1 + idx, str, len);
 111
 112   if (HP_TIMING_AVAIL)
 113     printf ("String %s, offset %zd:", str, idx);
 114
 115   FOR_EACH_IMPL (impl, 0)
 116     do_one_test (impl, buf1, BUF1PAGES * page_size, str, len, buf1 + idx);
 117
 118   memcpy (buf1 + idx, tmpbuf, len);
 119
 120   if (HP_TIMING_AVAIL)
 121     putchar ('\n');
 122 }
 123
 124 static void
 125 do_random_tests (void)
 126 {
 127   for (size_t n = 0; n < ITERATIONS; ++n)
 128     {
 129       char tmpbuf[32];
 130
 131       size_t shift = random () % 11;
 132       size_t rel = random () % ((2 << (shift + 1)) * 64);
 133       size_t idx = MIN ((2 << shift) * 64 + rel, BUF1PAGES * page_size - 2);
 134       size_t len = random () % (sizeof (tmpbuf) - 1) + 1;
 135       len = MIN (len, BUF1PAGES * page_size - idx - 1);
 136       memcpy (tmpbuf, buf1 + idx, len);
 137       for (size_t i = random () % len / 2 + 1; i > 0; --i)
 138         {
 139           size_t off = random () % len;
 140           char ch = '0' + random () % 10;
 141
 142           buf1[idx + off] = ch;
 143         }
 144
 145       if (HP_TIMING_AVAIL)
 146         printf ("String %.*s, offset %zd:", (int) len, buf1 + idx, idx);
 147
 148       FOR_EACH_IMPL (impl, 0)
 149         do_one_test (impl, buf1, BUF1PAGES * page_size, buf1 + idx, len,
 150                      buf1 + idx);
 151
 152       if (HP_TIMING_AVAIL)
 153         putchar ('\n');
 154
 155       memcpy (buf1 + idx, tmpbuf, len);
 156     }
 157 }
 158
 159 static void
 160 check1 (void)
 161 {
 162
 163   const char search_buf_data[5] = { 0x56, 0x34, 0x12, 0x78, 0x78 };
 164   const char pattern[2] = { 0x78, 0x56 };
 165   void *search_buf = (void *) buf1 + page_size - sizeof search_buf_data;
 166   void *exp_result;
 167
 168   memcpy (search_buf, search_buf_data, sizeof search_buf_data);
 169   exp_result = simple_memmem (search_buf, sizeof search_buf_data,
 170                               pattern, sizeof pattern);
 171   FOR_EACH_IMPL (impl, 0)
 172     check_result (impl, search_buf, sizeof search_buf_data,
 173                   pattern, sizeof pattern, exp_result);
 174 }
 175
 176 static const char *const strs[] =
 177   {
 178     "00000", "00112233", "0123456789", "0000111100001111",
 179     "00000111110000022222", "012345678901234567890",
 180     "abc0", "aaaa0", "abcabc0"
 181   };
 182
 183
 184 int
 185 test_main (void)
 186 {
 187   size_t i;
 188
 189   test_init ();
 190
 191   check1 ();
 192
 193   printf ("%23s", "");
 194   FOR_EACH_IMPL (impl, 0)
 195     printf ("\t%s", impl->name);
 196   putchar ('\n');
 197
 198   for (i = 0; i < BUF1PAGES * page_size; ++i)
 199     buf1[i] = 60 + random () % 32;
 200
 201   for (i = 0; i < sizeof (strs) / sizeof (strs[0]); ++i)
 202     for (size_t j = 0; j < 120; j += 7)
 203       {
 204         size_t len = strlen (strs[i]);
 205
 206         do_test (strs[i], len, j);
 207       }
 208
 209   do_random_tests ();
 210   return ret;
 211 }
 212
 213 #include "../test-skeleton.c"