string/test-strcmp.c

   1 /* Test and measure strcmp and wcscmp functions.
   2    Copyright (C) 1999-2022 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_LEN (getpagesize () * 3)
  20 #define MIN_PAGE_SIZE (TEST_LEN + 2 * getpagesize ())
  21
  22 #define TEST_MAIN
  23 #ifdef WIDE
  24 # define TEST_NAME "wcscmp"
  25 #else
  26 # define TEST_NAME "strcmp"
  27 #endif
  28 #include "test-string.h"
  29 #include <support/test-driver.h>
  30
  31 #ifdef WIDE
  32 # include <wchar.h>
  33
  34 # define L(str) L##str
  35 # define STRCMP wcscmp
  36 # define STRCPY wcscpy
  37 # define STRLEN wcslen
  38 # define MEMCPY wmemcpy
  39 # define SIMPLE_STRCMP simple_wcscmp
  40 # define CHAR wchar_t
  41 # define UCHAR wchar_t
  42 # define CHARBYTES 4
  43 # define CHARBYTESLOG 2
  44 # define CHARALIGN __alignof__ (CHAR)
  45 # define MIDCHAR 0x7fffffff
  46 # define LARGECHAR 0xfffffffe
  47 # define CHAR__MAX WCHAR_MAX
  48 # define CHAR__MIN WCHAR_MIN
  49
  50 /* Wcscmp uses signed semantics for comparison, not unsigned */
  51 /* Avoid using substraction since possible overflow */
  52
  53 int
  54 simple_wcscmp (const wchar_t *s1, const wchar_t *s2)
  55 {
  56   wchar_t c1, c2;
  57   do
  58     {
  59       c1 = *s1++;
  60       c2 = *s2++;
  61       if (c2 == L'\0')
  62       return c1 - c2;
  63     }
  64   while (c1 == c2);
  65
  66   return c1 < c2 ? -1 : 1;
  67 }
  68
  69 #else
  70 # include <limits.h>
  71
  72 # define L(str) str
  73 # define STRCMP strcmp
  74 # define STRCPY strcpy
  75 # define STRLEN strlen
  76 # define MEMCPY memcpy
  77 # define SIMPLE_STRCMP simple_strcmp
  78 # define CHAR char
  79 # define UCHAR unsigned char
  80 # define CHARBYTES 1
  81 # define CHARBYTESLOG 0
  82 # define CHARALIGN 1
  83 # define MIDCHAR 0x7f
  84 # define LARGECHAR 0xfe
  85 # define CHAR__MAX CHAR_MAX
  86 # define CHAR__MIN CHAR_MIN
  87
  88 /* Strcmp uses unsigned semantics for comparison. */
  89 int
  90 simple_strcmp (const char *s1, const char *s2)
  91 {
  92   int ret;
  93
  94   while ((ret = *(unsigned char *) s1 - *(unsigned char*) s2++) == 0 && *s1++);
  95   return ret;
  96 }
  97
  98 #endif
  99
 100 typedef int (*proto_t) (const CHAR *, const CHAR *);
 101
 102 IMPL (STRCMP, 1)
 103
 104 static int
 105 check_result (impl_t *impl,
 106              const CHAR *s1, const CHAR *s2,
 107              int exp_result)
 108 {
 109   int result = CALL (impl, s1, s2);
 110   if ((exp_result == 0 && result != 0)
 111       || (exp_result < 0 && result >= 0)
 112       || (exp_result > 0 && result <= 0))
 113     {
 114       error (0, 0, "Wrong result in function %s %d %d", impl->name,
 115              result, exp_result);
 116       ret = 1;
 117       return -1;
 118     }
 119
 120   return 0;
 121 }
 122
 123 static void
 124 do_one_test (impl_t *impl,
 125              const CHAR *s1, const CHAR *s2,
 126              int exp_result)
 127 {
 128   if (check_result (impl, s1, s2, exp_result) < 0)
 129     return;
 130 }
 131
 132 static void
 133 do_test (size_t align1, size_t align2, size_t len, int max_char,
 134          int exp_result)
 135 {
 136   size_t i;
 137
 138   CHAR *s1, *s2;
 139
 140   if (len == 0)
 141     return;
 142
 143   align1 &= ~(CHARBYTES - 1);
 144   align2 &= ~(CHARBYTES - 1);
 145
 146   align1 &= getpagesize () - 1;
 147   if (align1 + (len + 1) * CHARBYTES >= page_size)
 148     return;
 149
 150   align2 &= getpagesize () - 1;
 151   if (align2 + (len + 1) * CHARBYTES >= page_size)
 152     return;
 153
 154   /* Put them close to the end of page.  */
 155   i = align1 + CHARBYTES * (len + 2);
 156   s1 = (CHAR *)(buf1 + ((page_size - i) / 16 * 16) + align1);
 157   i = align2 + CHARBYTES * (len + 2);
 158   s2 = (CHAR *)(buf2 + ((page_size - i) / 16 * 16) + align2);
 159
 160   for (i = 0; i < len; i++)
 161     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % max_char;
 162
 163   s1[len] = s2[len] = 0;
 164   s1[len + 1] = 23;
 165   s2[len + 1] = 24 + exp_result;
 166   s2[len - 1] -= exp_result;
 167
 168   FOR_EACH_IMPL (impl, 0)
 169   do_one_test (impl, s1, s2, exp_result);
 170 }
 171
 172
 173 static void
 174 do_random_tests (void)
 175 {
 176         UCHAR *p1 = (UCHAR *) (buf1 + page_size - 512 * CHARBYTES);
 177         UCHAR *p2 = (UCHAR *) (buf2 + page_size - 512 * CHARBYTES);
 178
 179         for (size_t n = 0; n < ITERATIONS; n++)
 180           {
 181             /* for wcscmp case align1 and align2 mean here alignment
 182                in wchar_t symbols, it equal 4*k alignment in bytes, we
 183                don't check other alignments like for example
 184                p1 = (wchar_t *)(buf1 + 1)
 185                because it's wrong using of wchar_t type.  */
 186             size_t align1 = random () & 31;
 187             size_t align2;
 188             if (random () & 1)
 189               align2 = random () & 31;
 190             else
 191               align2 = align1 + (random () & 24);
 192             size_t pos = random () & 511;
 193             size_t j = align1 > align2 ? align1 : align2;
 194             if (pos + j >= 511)
 195               pos = 510 - j - (random () & 7);
 196             size_t len1 = random () & 511;
 197             if (pos >= len1 && (random () & 1))
 198               len1 = pos + (random () & 7);
 199             if (len1 + j >= 512)
 200               len1 = 511 - j - (random () & 7);
 201             size_t len2;
 202             if (pos >= len1)
 203               len2 = len1;
 204             else
 205               len2 = len1 + (len1 != 511 - j ? random () % (511 - j - len1) : 0);
 206             j = (pos > len2 ? pos : len2) + align1 + 64;
 207             if (j > 512)
 208               j = 512;
 209             for (size_t i = 0; i < j; ++i)
 210               {
 211                 p1[i] = random () & 255;
 212                 if (i < len1 + align1 && !p1[i])
 213                   {
 214                     p1[i] = random () & 255;
 215                     if (!p1[i])
 216                       p1[i] = 1 + (random () & 127);
 217                   }
 218               }
 219             for (size_t i = 0; i < j; ++i)
 220               {
 221                 p2[i] = random () & 255;
 222                 if (i < len2 + align2 && !p2[i])
 223                   {
 224                     p2[i] = random () & 255;
 225                     if (!p2[i])
 226                       p2[i] = 1 + (random () & 127);
 227                   }
 228               }
 229
 230             int result = 0;
 231             MEMCPY (p2 + align2, p1 + align1, pos);
 232             if (pos < len1)
 233               {
 234                 if (p2[align2 + pos] == p1[align1 + pos])
 235                   {
 236                     p2[align2 + pos] = random () & 255;
 237                     if (p2[align2 + pos] == p1[align1 + pos])
 238                       p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
 239                   }
 240
 241                 if (p1[align1 + pos] < p2[align2 + pos])
 242                   result = -1;
 243                 else
 244                   result = 1;
 245               }
 246             p1[len1 + align1] = 0;
 247             p2[len2 + align2] = 0;
 248
 249             FOR_EACH_IMPL (impl, 1)
 250               {
 251                 int r = CALL (impl, (CHAR *) (p1 + align1), (CHAR *) (p2 + align2));
 252                 /* Test whether on 64-bit architectures where ABI requires
 253                    callee to promote has the promotion been done.  */
 254                 asm ("" : "=g" (r) : "0" (r));
 255                 if ((r == 0 && result)
 256                     || (r < 0 && result >= 0)
 257                     || (r > 0 && result <= 0))
 258                   {
 259                     error (0, 0, "Iteration %zd - wrong result in function %s (align in bytes: %zd, align in bytes: %zd, len1:  %zd, len2: %zd, pos: %zd) %d != %d, p1 %p p2 %p",
 260                            n, impl->name, (size_t) (p1 + align1) & 63, (size_t) (p1 + align2) & 63, len1, len2, pos, r, result, p1, p2);
 261                     ret = 1;
 262                   }
 263               }
 264      }
 265 }
 266
 267 static void
 268 check (void)
 269 {
 270   CHAR *s1 = (CHAR *) (buf1 + 0xb2c);
 271   CHAR *s2 = (CHAR *) (buf1 + 0xfd8);
 272
 273   STRCPY(s1, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrs"));
 274   STRCPY(s2, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkLMNOPQRSTUV"));
 275
 276   /* Check correct working for negatives values */
 277
 278   s1[0] = 1;
 279   s2[0] = 1;
 280   s1[1] = 1;
 281   s2[1] = 1;
 282   s1[2] = -1;
 283   s2[2] = 3;
 284   s1[3] = 0;
 285   s2[3] = -1;
 286
 287   /* Check possible overflow bug, actual more for wcscmp */
 288
 289   s1[7] = CHAR__MIN;
 290   s2[7] = CHAR__MAX;
 291
 292   size_t l1 = STRLEN (s1);
 293   size_t l2 = STRLEN (s2);
 294
 295   for (size_t i1 = 0; i1 < l1; i1++)
 296     for (size_t i2 = 0; i2 < l2; i2++)
 297       {
 298                 int exp_result = SIMPLE_STRCMP (s1 + i1, s2 + i2);
 299                 FOR_EACH_IMPL (impl, 0)
 300                 check_result (impl, s1 + i1, s2 + i2, exp_result);
 301       }
 302
 303   /* Test cases where there are multiple zero bytes after the first.  */
 304
 305   for (size_t i = 0; i < 16 + 1; i++)
 306     {
 307       s1[i] = 0x00;
 308       s2[i] = 0x00;
 309     }
 310
 311   for (size_t i = 0; i < 16; i++)
 312     {
 313       int exp_result;
 314
 315       for (int val = 0x01; val < 0x100; val++)
 316         {
 317           for (size_t j = 0; j < i; j++)
 318             {
 319               s1[j] = val;
 320               s2[j] = val;
 321             }
 322
 323           s2[i] = val;
 324
 325           exp_result = SIMPLE_STRCMP (s1, s2);
 326           FOR_EACH_IMPL (impl, 0)
 327             check_result (impl, s1, s2, exp_result);
 328         }
 329     }
 330 }
 331
 332 static void
 333 check2 (void)
 334 {
 335   /* To trigger bug 25933, we need a size that is equal to the vector
 336      length times 4. In the case of AVX2 for Intel, we need 32 * 4.  We
 337      make this test generic and run it for all architectures as additional
 338      boundary testing for such related algorithms.  */
 339   size_t size = 32 * 4;
 340   CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size);
 341   CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size);
 342   int exp_result;
 343
 344   memset (s1, 'a', page_size);
 345   memset (s2, 'a', page_size);
 346   s1[(page_size / CHARBYTES) - 1] = (CHAR) 0;
 347   s2[(page_size / CHARBYTES) - 1] = (CHAR) 0;
 348
 349   /* Iterate over a size that is just below where we expect the bug to
 350      trigger up to the size we expect will trigger the bug e.g. [99-128].
 351      Likewise iterate the start of two strings between 30 and 31 bytes
 352      away from the boundary to simulate alignment changes.  */
 353   for (size_t s = 99; s <= size; s++)
 354     for (size_t s1a = 30; s1a < 32; s1a++)
 355       for (size_t s2a = 30; s2a < 32; s2a++)
 356         {
 357           CHAR *s1p = s1 + (page_size / CHARBYTES - s) - s1a;
 358           CHAR *s2p = s2 + (page_size / CHARBYTES - s) - s2a;
 359           exp_result = SIMPLE_STRCMP (s1p, s2p);
 360           FOR_EACH_IMPL (impl, 0)
 361             check_result (impl, s1p, s2p, exp_result);
 362         }
 363 }
 364
 365 static void
 366 check3 (void)
 367 {
 368   size_t size = 0xd000 + 0x4000;
 369   CHAR *s1, *s2;
 370   CHAR *buffer1 = mmap (NULL, size, PROT_READ | PROT_WRITE,
 371                         MAP_PRIVATE | MAP_ANON, -1, 0);
 372   CHAR *buffer2 = mmap (NULL, size, PROT_READ | PROT_WRITE,
 373                         MAP_PRIVATE | MAP_ANON, -1, 0);
 374   if (buffer1 == MAP_FAILED || buffer1 == MAP_FAILED)
 375     error (EXIT_UNSUPPORTED, errno, "mmap failed");
 376
 377   s1 = (CHAR *) (buffer1 + 0x8f8 / sizeof (CHAR));
 378   s2 = (CHAR *) (buffer2 + 0xcff3 / sizeof (CHAR));
 379
 380   STRCPY(s1, L("/export/redhat/rpms/BUILD/java-1.8.0-openjdk-1.8.0.312.b07-2.fc35.x86_64/openjdk/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/util/PathDocFileFactory.java"));
 381   STRCPY(s2, L("/export/redhat/rpms/BUILD/java-1.8.0-openjdk-1.8.0.312.b07-2.fc35.x86_64/openjdk/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/taglets/ThrowsTaglet.java"));
 382
 383   int exp_result = SIMPLE_STRCMP (s1, s2);
 384   FOR_EACH_IMPL (impl, 0)
 385     check_result (impl, s1, s2, exp_result);
 386
 387   munmap ((void *) buffer1, size);
 388   munmap ((void *) buffer2, size);
 389 }
 390
 391 int
 392 test_main (void)
 393 {
 394   size_t i, j, k;
 395   const size_t test_len = MIN(TEST_LEN, 3 * 4096);
 396   test_init ();
 397   check();
 398   check2 ();
 399   check3 ();
 400
 401   printf ("%23s", "");
 402   FOR_EACH_IMPL (impl, 0)
 403     printf ("\t%s", impl->name);
 404   putchar ('\n');
 405
 406   for (i = 1; i < 32; ++i)
 407     {
 408       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 0);
 409       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 1);
 410       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, -1);
 411     }
 412
 413   for (i = 1; i < 10 + CHARBYTESLOG; ++i)
 414     {
 415       do_test (0, 0, 2 << i, MIDCHAR, 0);
 416       do_test (0, 0, 2 << i, LARGECHAR, 0);
 417       do_test (0, 0, 2 << i, MIDCHAR, 1);
 418       do_test (0, 0, 2 << i, LARGECHAR, 1);
 419       do_test (0, 0, 2 << i, MIDCHAR, -1);
 420       do_test (0, 0, 2 << i, LARGECHAR, -1);
 421       do_test (0, CHARBYTES * i, 2 << i, MIDCHAR, 1);
 422       do_test (CHARBYTES * i, CHARBYTES * (i + 1), 2 << i, LARGECHAR, 1);
 423     }
 424
 425   for (i = 1; i < 8; ++i)
 426     {
 427       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 0);
 428       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 0);
 429       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 1);
 430       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 1);
 431       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, -1);
 432       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, -1);
 433     }
 434
 435   for (j = 0; j < 160; ++j)
 436     {
 437       for (i = 0; i < test_len;)
 438         {
 439           do_test (getpagesize () - j - 1, 0, i, 127, 0);
 440           do_test (getpagesize () - j - 1, 0, i, 127, 1);
 441           do_test (getpagesize () - j - 1, 0, i, 127, -1);
 442
 443           do_test (getpagesize () - j - 1, j, i, 127, 0);
 444           do_test (getpagesize () - j - 1, j, i, 127, 1);
 445           do_test (getpagesize () - j - 1, j, i, 127, -1);
 446
 447           do_test (0, getpagesize () - j - 1, i, 127, 0);
 448           do_test (0, getpagesize () - j - 1, i, 127, 1);
 449           do_test (0, getpagesize () - j - 1, i, 127, -1);
 450
 451           do_test (j, getpagesize () - j - 1, i, 127, 0);
 452           do_test (j, getpagesize () - j - 1, i, 127, 1);
 453           do_test (j, getpagesize () - j - 1, i, 127, -1);
 454
 455           for (k = 2; k <= 128; k += k)
 456             {
 457               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, 0);
 458               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
 459                        0);
 460               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, 1);
 461               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
 462                        1);
 463               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, -1);
 464               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
 465                        -1);
 466             }
 467
 468           if (i < 32)
 469             {
 470               i += 1;
 471             }
 472           else if (i < 161)
 473             {
 474               i += 7;
 475             }
 476           else if (i + 161 < test_len)
 477             {
 478               i += 31;
 479               i *= 17;
 480               i /= 16;
 481               if (i + 161 > test_len)
 482                 {
 483                   i = test_len - 160;
 484                 }
 485             }
 486           else if (i + 32 < test_len)
 487             {
 488               i += 7;
 489             }
 490           else
 491             {
 492               i += 1;
 493             }
 494         }
 495     }
 496
 497   do_random_tests ();
 498   return ret;
 499 }
 500
 501 #include <support/test-driver.c>