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_MAIN
  20 #ifdef WIDE
  21 # define TEST_NAME "wcscmp"
  22 #else
  23 # define TEST_NAME "strcmp"
  24 #endif
  25 #include "test-string.h"
  26 #include <support/test-driver.h>
  27
  28 #ifdef WIDE
  29 # include <wchar.h>
  30
  31 # define L(str) L##str
  32 # define STRCMP wcscmp
  33 # define STRCPY wcscpy
  34 # define STRLEN wcslen
  35 # define MEMCPY wmemcpy
  36 # define SIMPLE_STRCMP simple_wcscmp
  37 # define STUPID_STRCMP stupid_wcscmp
  38 # define CHAR wchar_t
  39 # define UCHAR wchar_t
  40 # define CHARBYTES 4
  41 # define CHARBYTESLOG 2
  42 # define CHARALIGN __alignof__ (CHAR)
  43 # define MIDCHAR 0x7fffffff
  44 # define LARGECHAR 0xfffffffe
  45 # define CHAR__MAX WCHAR_MAX
  46 # define CHAR__MIN WCHAR_MIN
  47
  48 /* Wcscmp uses signed semantics for comparison, not unsigned */
  49 /* Avoid using substraction since possible overflow */
  50
  51 int
  52 simple_wcscmp (const wchar_t *s1, const wchar_t *s2)
  53 {
  54   wchar_t c1, c2;
  55   do
  56     {
  57       c1 = *s1++;
  58       c2 = *s2++;
  59       if (c2 == L'\0')
  60       return c1 - c2;
  61     }
  62   while (c1 == c2);
  63
  64   return c1 < c2 ? -1 : 1;
  65 }
  66
  67 int
  68 stupid_wcscmp (const wchar_t *s1, const wchar_t *s2)
  69 {
  70   size_t ns1 = wcslen (s1) + 1;
  71   size_t ns2 = wcslen (s2) + 1;
  72   size_t n = ns1 < ns2 ? ns1 : ns2;
  73   int ret = 0;
  74
  75   wchar_t c1, c2;
  76
  77   while (n--) {
  78     c1 = *s1++;
  79     c2 = *s2++;
  80     if ((ret = c1 < c2 ? -1 : c1 == c2 ? 0 : 1) != 0)
  81       break;
  82   }
  83   return ret;
  84 }
  85
  86 #else
  87 # include <limits.h>
  88
  89 # define L(str) str
  90 # define STRCMP strcmp
  91 # define STRCPY strcpy
  92 # define STRLEN strlen
  93 # define MEMCPY memcpy
  94 # define SIMPLE_STRCMP simple_strcmp
  95 # define STUPID_STRCMP stupid_strcmp
  96 # define CHAR char
  97 # define UCHAR unsigned char
  98 # define CHARBYTES 1
  99 # define CHARBYTESLOG 0
 100 # define CHARALIGN 1
 101 # define MIDCHAR 0x7f
 102 # define LARGECHAR 0xfe
 103 # define CHAR__MAX CHAR_MAX
 104 # define CHAR__MIN CHAR_MIN
 105
 106 /* Strcmp uses unsigned semantics for comparison. */
 107 int
 108 simple_strcmp (const char *s1, const char *s2)
 109 {
 110   int ret;
 111
 112   while ((ret = *(unsigned char *) s1 - *(unsigned char*) s2++) == 0 && *s1++);
 113   return ret;
 114 }
 115
 116 int
 117 stupid_strcmp (const char *s1, const char *s2)
 118 {
 119   size_t ns1 = strlen (s1) + 1;
 120   size_t ns2 = strlen (s2) + 1;
 121   size_t n = ns1 < ns2 ? ns1 : ns2;
 122   int ret = 0;
 123
 124   while (n--)
 125     if ((ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) != 0)
 126       break;
 127   return ret;
 128 }
 129 #endif
 130
 131 typedef int (*proto_t) (const CHAR *, const CHAR *);
 132
 133 IMPL (STUPID_STRCMP, 1)
 134 IMPL (SIMPLE_STRCMP, 1)
 135 IMPL (STRCMP, 1)
 136
 137 static int
 138 check_result (impl_t *impl,
 139              const CHAR *s1, const CHAR *s2,
 140              int exp_result)
 141 {
 142   int result = CALL (impl, s1, s2);
 143   if ((exp_result == 0 && result != 0)
 144       || (exp_result < 0 && result >= 0)
 145       || (exp_result > 0 && result <= 0))
 146     {
 147       error (0, 0, "Wrong result in function %s %d %d", impl->name,
 148              result, exp_result);
 149       ret = 1;
 150       return -1;
 151     }
 152
 153   return 0;
 154 }
 155
 156 static void
 157 do_one_test (impl_t *impl,
 158              const CHAR *s1, const CHAR *s2,
 159              int exp_result)
 160 {
 161   if (check_result (impl, s1, s2, exp_result) < 0)
 162     return;
 163 }
 164
 165 static void
 166 do_test (size_t align1, size_t align2, size_t len, int max_char,
 167          int exp_result)
 168 {
 169   size_t i;
 170
 171   CHAR *s1, *s2;
 172
 173   if (len == 0)
 174     return;
 175
 176   align1 &= 63;
 177   if (align1 + (len + 1) * CHARBYTES >= page_size)
 178     return;
 179
 180   align2 &= 63;
 181   if (align2 + (len + 1) * CHARBYTES >= page_size)
 182     return;
 183
 184   /* Put them close to the end of page.  */
 185   i = align1 + CHARBYTES * (len + 2);
 186   s1 = (CHAR *) (buf1 + ((page_size - i) / 16 * 16) + align1);
 187   i = align2 + CHARBYTES * (len + 2);
 188   s2 = (CHAR *) (buf2 + ((page_size - i) / 16 * 16)  + align2);
 189
 190   for (i = 0; i < len; i++)
 191     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % max_char;
 192
 193   s1[len] = s2[len] = 0;
 194   s1[len + 1] = 23;
 195   s2[len + 1] = 24 + exp_result;
 196   s2[len - 1] -= exp_result;
 197
 198   FOR_EACH_IMPL (impl, 0)
 199     do_one_test (impl, s1, s2, exp_result);
 200 }
 201
 202 static void
 203 do_random_tests (void)
 204 {
 205         UCHAR *p1 = (UCHAR *) (buf1 + page_size - 512 * CHARBYTES);
 206         UCHAR *p2 = (UCHAR *) (buf2 + page_size - 512 * CHARBYTES);
 207
 208         for (size_t n = 0; n < ITERATIONS; n++)
 209           {
 210             /* for wcscmp case align1 and align2 mean here alignment
 211                in wchar_t symbols, it equal 4*k alignment in bytes, we
 212                don't check other alignments like for example
 213                p1 = (wchar_t *)(buf1 + 1)
 214                because it's wrong using of wchar_t type.  */
 215             size_t align1 = random () & 31;
 216             size_t align2;
 217             if (random () & 1)
 218               align2 = random () & 31;
 219             else
 220               align2 = align1 + (random () & 24);
 221             size_t pos = random () & 511;
 222             size_t j = align1 > align2 ? align1 : align2;
 223             if (pos + j >= 511)
 224               pos = 510 - j - (random () & 7);
 225             size_t len1 = random () & 511;
 226             if (pos >= len1 && (random () & 1))
 227               len1 = pos + (random () & 7);
 228             if (len1 + j >= 512)
 229               len1 = 511 - j - (random () & 7);
 230             size_t len2;
 231             if (pos >= len1)
 232               len2 = len1;
 233             else
 234               len2 = len1 + (len1 != 511 - j ? random () % (511 - j - len1) : 0);
 235             j = (pos > len2 ? pos : len2) + align1 + 64;
 236             if (j > 512)
 237               j = 512;
 238             for (size_t i = 0; i < j; ++i)
 239               {
 240                 p1[i] = random () & 255;
 241                 if (i < len1 + align1 && !p1[i])
 242                   {
 243                     p1[i] = random () & 255;
 244                     if (!p1[i])
 245                       p1[i] = 1 + (random () & 127);
 246                   }
 247               }
 248             for (size_t i = 0; i < j; ++i)
 249               {
 250                 p2[i] = random () & 255;
 251                 if (i < len2 + align2 && !p2[i])
 252                   {
 253                     p2[i] = random () & 255;
 254                     if (!p2[i])
 255                       p2[i] = 1 + (random () & 127);
 256                   }
 257               }
 258
 259             int result = 0;
 260             MEMCPY (p2 + align2, p1 + align1, pos);
 261             if (pos < len1)
 262               {
 263                 if (p2[align2 + pos] == p1[align1 + pos])
 264                   {
 265                     p2[align2 + pos] = random () & 255;
 266                     if (p2[align2 + pos] == p1[align1 + pos])
 267                       p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
 268                   }
 269
 270                 if (p1[align1 + pos] < p2[align2 + pos])
 271                   result = -1;
 272                 else
 273                   result = 1;
 274               }
 275             p1[len1 + align1] = 0;
 276             p2[len2 + align2] = 0;
 277
 278             FOR_EACH_IMPL (impl, 1)
 279               {
 280                 int r = CALL (impl, (CHAR *) (p1 + align1), (CHAR *) (p2 + align2));
 281                 /* Test whether on 64-bit architectures where ABI requires
 282                    callee to promote has the promotion been done.  */
 283                 asm ("" : "=g" (r) : "0" (r));
 284                 if ((r == 0 && result)
 285                     || (r < 0 && result >= 0)
 286                     || (r > 0 && result <= 0))
 287                   {
 288                     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",
 289                            n, impl->name, (size_t) (p1 + align1) & 63, (size_t) (p1 + align2) & 63, len1, len2, pos, r, result, p1, p2);
 290                     ret = 1;
 291                   }
 292               }
 293      }
 294 }
 295
 296 static void
 297 check (void)
 298 {
 299   CHAR *s1 = (CHAR *) (buf1 + 0xb2c);
 300   CHAR *s2 = (CHAR *) (buf1 + 0xfd8);
 301
 302   STRCPY(s1, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrs"));
 303   STRCPY(s2, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkLMNOPQRSTUV"));
 304
 305   /* Check correct working for negatives values */
 306
 307   s1[0] = 1;
 308   s2[0] = 1;
 309   s1[1] = 1;
 310   s2[1] = 1;
 311   s1[2] = -1;
 312   s2[2] = 3;
 313   s1[3] = 0;
 314   s2[3] = -1;
 315
 316   /* Check possible overflow bug, actual more for wcscmp */
 317
 318   s1[7] = CHAR__MIN;
 319   s2[7] = CHAR__MAX;
 320
 321   size_t l1 = STRLEN (s1);
 322   size_t l2 = STRLEN (s2);
 323
 324   for (size_t i1 = 0; i1 < l1; i1++)
 325     for (size_t i2 = 0; i2 < l2; i2++)
 326       {
 327                 int exp_result = SIMPLE_STRCMP (s1 + i1, s2 + i2);
 328                 FOR_EACH_IMPL (impl, 0)
 329                 check_result (impl, s1 + i1, s2 + i2, exp_result);
 330       }
 331
 332   /* Test cases where there are multiple zero bytes after the first.  */
 333
 334   for (size_t i = 0; i < 16 + 1; i++)
 335     {
 336       s1[i] = 0x00;
 337       s2[i] = 0x00;
 338     }
 339
 340   for (size_t i = 0; i < 16; i++)
 341     {
 342       int exp_result;
 343
 344       for (int val = 0x01; val < 0x100; val++)
 345         {
 346           for (size_t j = 0; j < i; j++)
 347             {
 348               s1[j] = val;
 349               s2[j] = val;
 350             }
 351
 352           s2[i] = val;
 353
 354           exp_result = SIMPLE_STRCMP (s1, s2);
 355           FOR_EACH_IMPL (impl, 0)
 356             check_result (impl, s1, s2, exp_result);
 357         }
 358     }
 359 }
 360
 361 static void
 362 check2 (void)
 363 {
 364   /* To trigger bug 25933, we need a size that is equal to the vector
 365      length times 4. In the case of AVX2 for Intel, we need 32 * 4.  We
 366      make this test generic and run it for all architectures as additional
 367      boundary testing for such related algorithms.  */
 368   size_t size = 32 * 4;
 369   CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size);
 370   CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size);
 371   int exp_result;
 372
 373   memset (s1, 'a', page_size);
 374   memset (s2, 'a', page_size);
 375   s1[(page_size / CHARBYTES) - 1] = (CHAR) 0;
 376   s2[(page_size / CHARBYTES) - 1] = (CHAR) 0;
 377
 378   /* Iterate over a size that is just below where we expect the bug to
 379      trigger up to the size we expect will trigger the bug e.g. [99-128].
 380      Likewise iterate the start of two strings between 30 and 31 bytes
 381      away from the boundary to simulate alignment changes.  */
 382   for (size_t s = 99; s <= size; s++)
 383     for (size_t s1a = 30; s1a < 32; s1a++)
 384       for (size_t s2a = 30; s2a < 32; s2a++)
 385         {
 386           CHAR *s1p = s1 + (page_size / CHARBYTES - s) - s1a;
 387           CHAR *s2p = s2 + (page_size / CHARBYTES - s) - s2a;
 388           exp_result = SIMPLE_STRCMP (s1p, s2p);
 389           FOR_EACH_IMPL (impl, 0)
 390             check_result (impl, s1p, s2p, exp_result);
 391         }
 392 }
 393
 394 static void
 395 check3 (void)
 396 {
 397   size_t size = 0xd000 + 0x4000;
 398   CHAR *s1, *s2;
 399   CHAR *buffer1 = mmap (NULL, size, PROT_READ | PROT_WRITE,
 400                         MAP_PRIVATE | MAP_ANON, -1, 0);
 401   CHAR *buffer2 = mmap (NULL, size, PROT_READ | PROT_WRITE,
 402                         MAP_PRIVATE | MAP_ANON, -1, 0);
 403   if (buffer1 == MAP_FAILED || buffer1 == MAP_FAILED)
 404     error (EXIT_UNSUPPORTED, errno, "mmap failed");
 405
 406   s1 = (CHAR *) (buffer1 + 0x8f8 / sizeof (CHAR));
 407   s2 = (CHAR *) (buffer2 + 0xcff3 / sizeof (CHAR));
 408
 409   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"));
 410   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"));
 411
 412   int exp_result = SIMPLE_STRCMP (s1, s2);
 413   FOR_EACH_IMPL (impl, 0)
 414     check_result (impl, s1, s2, exp_result);
 415
 416   munmap ((void *) buffer1, size);
 417   munmap ((void *) buffer2, size);
 418 }
 419
 420 int
 421 test_main (void)
 422 {
 423   size_t i;
 424
 425   test_init ();
 426   check();
 427   check2 ();
 428   check3 ();
 429
 430   printf ("%23s", "");
 431   FOR_EACH_IMPL (impl, 0)
 432     printf ("\t%s", impl->name);
 433   putchar ('\n');
 434
 435   for (i = 1; i < 32; ++i)
 436     {
 437       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 0);
 438       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 1);
 439       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, -1);
 440     }
 441
 442   for (i = 1; i < 10 + CHARBYTESLOG; ++i)
 443     {
 444       do_test (0, 0, 2 << i, MIDCHAR, 0);
 445       do_test (0, 0, 2 << i, LARGECHAR, 0);
 446       do_test (0, 0, 2 << i, MIDCHAR, 1);
 447       do_test (0, 0, 2 << i, LARGECHAR, 1);
 448       do_test (0, 0, 2 << i, MIDCHAR, -1);
 449       do_test (0, 0, 2 << i, LARGECHAR, -1);
 450       do_test (0, CHARBYTES * i, 2 << i, MIDCHAR, 1);
 451       do_test (CHARBYTES * i, CHARBYTES * (i + 1), 2 << i, LARGECHAR, 1);
 452     }
 453
 454   for (i = 1; i < 8; ++i)
 455     {
 456       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 0);
 457       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 0);
 458       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 1);
 459       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 1);
 460       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, -1);
 461       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, -1);
 462     }
 463
 464   do_random_tests ();
 465   return ret;
 466 }
 467
 468 #include <support/test-driver.c>