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, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #define TEST_MAIN
  22 #define BUF1PAGES 20
  23 #define ITERATIONS 500
  24 #include "test-string.h"
  25
  26 typedef char *(*proto_t) (const void *, size_t, const void *, size_t);
  27 void *simple_memmem (const void *, size_t, const void *, size_t);
  28
  29 IMPL (simple_memmem, 0)
  30 IMPL (memmem, 1)
  31
  32 void *
  33 simple_memmem (const void *haystack, size_t haystack_len, const void *needle,
  34                size_t needle_len)
  35 {
  36   const char *begin;
  37   const char *const last_possible
  38     = (const char *) haystack + haystack_len - needle_len;
  39
  40   if (needle_len == 0)
  41     /* The first occurrence of the empty string is deemed to occur at
  42        the beginning of the string.  */
  43     return (void *) haystack;
  44
  45   /* Sanity check, otherwise the loop might search through the whole
  46      memory.  */
  47   if (__builtin_expect (haystack_len < needle_len, 0))
  48     return NULL;
  49
  50   for (begin = (const char *) haystack; begin <= last_possible; ++begin)
  51     if (begin[0] == ((const char *) needle)[0] &&
  52         !memcmp ((const void *) &begin[1],
  53                  (const void *) ((const char *) needle + 1),
  54                  needle_len - 1))
  55       return (void *) begin;
  56
  57   return NULL;
  58 }
  59
  60 static void
  61 do_one_test (impl_t *impl, const void *haystack, size_t haystack_len,
  62              const void *needle, size_t needle_len, const void *expected)
  63 {
  64   void *res;
  65
  66   res = CALL (impl, haystack, haystack_len, needle, needle_len);
  67   if (res != expected)
  68     {
  69       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  70              res, expected);
  71       ret = 1;
  72       return;
  73     }
  74
  75   if (HP_TIMING_AVAIL)
  76     {
  77       hp_timing_t start __attribute ((unused));
  78       hp_timing_t stop __attribute ((unused));
  79       hp_timing_t best_time = ~ (hp_timing_t) 0;
  80       size_t i;
  81
  82       for (i = 0; i < 32; ++i)
  83         {
  84           HP_TIMING_NOW (start);
  85           CALL (impl, haystack, haystack_len, needle, needle_len);
  86           HP_TIMING_NOW (stop);
  87           HP_TIMING_BEST (best_time, start, stop);
  88         }
  89
  90       printf ("\t%zd", (size_t) best_time);
  91     }
  92 }
  93
  94 static void
  95 do_test (const char *str, size_t len, size_t idx)
  96 {
  97   char tmpbuf[len];
  98
  99   memcpy (tmpbuf, buf1 + idx, len);
 100   memcpy (buf1 + idx, str, len);
 101
 102   if (HP_TIMING_AVAIL)
 103     printf ("String %s, offset %zd:", str, idx);
 104
 105   FOR_EACH_IMPL (impl, 0)
 106     do_one_test (impl, buf1, BUF1PAGES * page_size, str, len, buf1 + idx);
 107
 108   memcpy (buf1 + idx, tmpbuf, len);
 109
 110   if (HP_TIMING_AVAIL)
 111     putchar ('\n');
 112 }
 113
 114 static void
 115 do_random_tests (void)
 116 {
 117   for (size_t n = 0; n < ITERATIONS; ++n)
 118     {
 119       char tmpbuf[32];
 120
 121       size_t shift = random () % 11;
 122       size_t rel = random () % ((2 << (shift + 1)) * 64);
 123       size_t idx = MIN ((2 << shift) * 64 + rel, BUF1PAGES * page_size - 2);
 124       size_t len = random () % (sizeof (tmpbuf) - 1) + 1;
 125       len = MIN (len, BUF1PAGES * page_size - idx - 1);
 126       memcpy (tmpbuf, buf1 + idx, len);
 127       for (size_t i = random () % len / 2 + 1; i > 0; --i)
 128         {
 129           size_t off = random () % len;
 130           char ch = '0' + random () % 10;
 131
 132           buf1[idx + off] = ch;
 133         }
 134
 135       if (HP_TIMING_AVAIL)
 136         printf ("String %.*s, offset %zd:", (int) len, buf1 + idx, idx);
 137
 138       FOR_EACH_IMPL (impl, 0)
 139         do_one_test (impl, buf1, BUF1PAGES * page_size, buf1 + idx, len,
 140                      buf1 + idx);
 141
 142       if (HP_TIMING_AVAIL)
 143         putchar ('\n');
 144
 145       memcpy (buf1 + idx, tmpbuf, len);
 146     }
 147 }
 148
 149
 150 static const char *const strs[] =
 151   {
 152     "00000", "00112233", "0123456789", "0000111100001111",
 153     "00000111110000022222", "012345678901234567890",
 154     "abc0", "aaaa0", "abcabc0"
 155   };
 156
 157
 158 int
 159 test_main (void)
 160 {
 161   size_t i;
 162
 163   test_init ();
 164
 165   printf ("%23s", "");
 166   FOR_EACH_IMPL (impl, 0)
 167     printf ("\t%s", impl->name);
 168   putchar ('\n');
 169
 170   for (i = 0; i < BUF1PAGES * page_size; ++i)
 171     buf1[i] = 60 + random () % 32;
 172
 173   for (i = 0; i < sizeof (strs) / sizeof (strs[0]); ++i)
 174     for (size_t j = 0; j < 120; j += 7)
 175       {
 176         size_t len = strlen (strs[i]);
 177
 178         do_test (strs[i], len, j);
 179       }
 180
 181   do_random_tests ();
 182   return ret;
 183 }
 184
 185 #include "../test-skeleton.c"