string/test-memcmp.c

   1 /* Test and measure memcmp functions.
   2    Copyright (C) 1999-2024 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 TEST_MEMCMPEQ
  21 # define TEST_NAME "__memcmpeq"
  22 #elif defined WIDE
  23 # define TEST_NAME "wmemcmp"
  24 #else
  25 # define TEST_NAME "memcmp"
  26 #endif
  27
  28 #include "test-string.h"
  29 #ifdef WIDE
  30 # include <inttypes.h>
  31 # include <wchar.h>
  32
  33 # define MEMCMP wmemcmp
  34 # define MEMCPY wmemcpy
  35 # define SIMPLE_MEMCMP simple_wmemcmp
  36 # define CHAR wchar_t
  37 # define UCHAR wchar_t
  38 # define CHARBYTES 4
  39 # define CHAR__MIN WCHAR_MIN
  40 # define CHAR__MAX WCHAR_MAX
  41
  42 int
  43 SIMPLE_MEMCMP (const wchar_t *s1, const wchar_t *s2, size_t n)
  44 {
  45   int ret = 0;
  46   /* Warning!
  47         wmemcmp has to use SIGNED comparison for elements.
  48         memcmp has to use UNSIGNED comparison for elements.
  49   */
  50   while (n-- && (ret = *s1 < *s2 ? -1 : *s1 == *s2 ? 0 : 1) == 0) {s1++; s2++;}
  51   return ret;
  52 }
  53 #else
  54 # include <limits.h>
  55 # ifdef TEST_MEMCMPEQ
  56 #  define MEMCMP __memcmpeq
  57 #  define SIMPLE_MEMCMP simple_memcmpeq
  58 # else
  59 #  define MEMCMP memcmp
  60 #  define SIMPLE_MEMCMP simple_memcmp
  61 # endif
  62 # define MEMCPY memcpy
  63 # define CHAR char
  64 # define MAX_CHAR 255
  65 # define UCHAR unsigned char
  66 # define CHARBYTES 1
  67 # define CHAR__MIN CHAR_MIN
  68 # define CHAR__MAX CHAR_MAX
  69
  70 int
  71 SIMPLE_MEMCMP (const char *s1, const char *s2, size_t n)
  72 {
  73   int ret = 0;
  74
  75   while (n-- && (ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) == 0);
  76   return ret;
  77 }
  78 #endif
  79
  80 #ifndef BAD_RESULT
  81 # define BAD_RESULT(result, expec)                                      \
  82     (((result) == 0 && (expec)) || ((result) < 0 && (expec) >= 0) ||    \
  83      ((result) > 0 && (expec) <= 0))
  84 # endif
  85
  86 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
  87
  88 IMPL (MEMCMP, 1)
  89
  90 static int
  91 check_result (impl_t *impl, const CHAR *s1, const CHAR *s2, size_t len,
  92               int exp_result)
  93 {
  94   int result = CALL (impl, s1, s2, len);
  95   if (BAD_RESULT(result, exp_result))
  96     {
  97       error (0, 0, "Wrong result in function %s %d %d", impl->name,
  98              result, exp_result);
  99       ret = 1;
 100       return -1;
 101     }
 102
 103   return 0;
 104 }
 105
 106 static void
 107 do_one_test (impl_t *impl, const CHAR *s1, const CHAR *s2, size_t len,
 108              int exp_result)
 109 {
 110   if (check_result (impl, s1, s2, len, exp_result) < 0)
 111     return;
 112 }
 113
 114 static void
 115 do_test (size_t align1, size_t align2, size_t len, int exp_result)
 116 {
 117   size_t i;
 118   CHAR *s1, *s2;
 119
 120   align1 &= (4096 - CHARBYTES);
 121   if (align1 + (len + 1) * CHARBYTES >= page_size)
 122     return;
 123
 124   align2 &= (4096 - CHARBYTES);
 125   if (align2 + (len + 1) * CHARBYTES >= page_size)
 126     return;
 127
 128   s1 = (CHAR *) (buf1 + align1);
 129   s2 = (CHAR *) (buf2 + align2);
 130
 131   for (i = 0; i < len; i++)
 132     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % CHAR__MAX;
 133
 134   if (len)
 135     {
 136       s1[len] = align1;
 137       s2[len] = align2;
 138       s2[len - 1] -= exp_result;
 139     }
 140   else
 141     {
 142       exp_result = 0;
 143     }
 144
 145   FOR_EACH_IMPL (impl, 0)
 146     do_one_test (impl, s1, s2, len, exp_result);
 147 }
 148
 149 static void
 150 do_random_tests (void)
 151 {
 152   size_t i, j, n, align1, align2, pos, len;
 153   int result;
 154   long r;
 155   UCHAR *p1 =  (UCHAR *) (buf1 + page_size - 512 * CHARBYTES);
 156   UCHAR *p2 =  (UCHAR *) (buf2 + page_size - 512 * CHARBYTES);
 157
 158   for (n = 0; n < ITERATIONS; n++)
 159     {
 160    align1 = random () & 31;
 161       if (random () & 1)
 162         align2 = random () & 31;
 163       else
 164         align2 = align1 + (random () & 24);
 165       pos = random () & 511;
 166       j = align1;
 167       if (align2 > j)
 168         j = align2;
 169       if (pos + j >= 512)
 170         pos = 511 - j - (random () & 7);
 171       len = random () & 511;
 172       if (len + j >= 512)
 173         len = 511 - j - (random () & 7);
 174       j = len + align1 + 64;
 175       if (j > 512) j = 512;
 176       for (i = 0; i < j; ++i)
 177         p1[i] = random () & 255;
 178       for (i = 0; i < j; ++i)
 179         p2[i] = random () & 255;
 180
 181       result = 0;
 182       if (pos >= len)
 183         MEMCPY ((CHAR *) p2 + align2, (const CHAR *) p1 + align1, len);
 184       else
 185         {
 186           MEMCPY ((CHAR *) p2 + align2, (const CHAR *) p1 + align1, pos);
 187           if (p2[align2 + pos] == p1[align1 + pos])
 188             {
 189               p2[align2 + pos] = random () & 255;
 190               if (p2[align2 + pos] == p1[align1 + pos])
 191                 p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
 192             }
 193
 194           if (p1[align1 + pos] < p2[align2 + pos])
 195             result = -1;
 196           else
 197             result = 1;
 198         }
 199
 200       FOR_EACH_IMPL (impl, 1)
 201         {
 202           r = CALL (impl, (CHAR *) p1 + align1, (const CHAR *) p2 + align2,
 203                     len);
 204           if (BAD_RESULT(r, result))
 205             {
 206               error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %zd, %zd, %zd) %ld != %d, p1 %p p2 %p",
 207                      n, impl->name, align1 * CHARBYTES & 63,  align2 * CHARBYTES & 63, len, pos, r, result, p1, p2);
 208               ret = 1;
 209             }
 210         }
 211     }
 212 }
 213
 214 static void
 215 check1 (void)
 216 {
 217   CHAR s1[116], s2[116];
 218   int n, exp_result;
 219
 220   s1[0] = -108;
 221   s2[0] = -108;
 222   s1[1] = 99;
 223   s2[1] = 99;
 224   s1[2] = -113;
 225   s2[2] = -113;
 226   s1[3] = 1;
 227   s2[3] = 1;
 228   s1[4] = 116;
 229   s2[4] = 116;
 230   s1[5] = 99;
 231   s2[5] = 99;
 232   s1[6] = -113;
 233   s2[6] = -113;
 234   s1[7] = 1;
 235   s2[7] = 1;
 236   s1[8] = 84;
 237   s2[8] = 84;
 238   s1[9] = 99;
 239   s2[9] = 99;
 240   s1[10] = -113;
 241   s2[10] = -113;
 242   s1[11] = 1;
 243   s2[11] = 1;
 244   s1[12] = 52;
 245   s2[12] = 52;
 246   s1[13] = 99;
 247   s2[13] = 99;
 248   s1[14] = -113;
 249   s2[14] = -113;
 250   s1[15] = 1;
 251   s2[15] = 1;
 252   s1[16] = -76;
 253   s2[16] = -76;
 254   s1[17] = -14;
 255   s2[17] = -14;
 256   s1[18] = -109;
 257   s2[18] = -109;
 258   s1[19] = 1;
 259   s2[19] = 1;
 260   s1[20] = -108;
 261   s2[20] = -108;
 262   s1[21] = -14;
 263   s2[21] = -14;
 264   s1[22] = -109;
 265   s2[22] = -109;
 266   s1[23] = 1;
 267   s2[23] = 1;
 268   s1[24] = 84;
 269   s2[24] = 84;
 270   s1[25] = -15;
 271   s2[25] = -15;
 272   s1[26] = -109;
 273   s2[26] = -109;
 274   s1[27] = 1;
 275   s2[27] = 1;
 276   s1[28] = 52;
 277   s2[28] = 52;
 278   s1[29] = -15;
 279   s2[29] = -15;
 280   s1[30] = -109;
 281   s2[30] = -109;
 282   s1[31] = 1;
 283   s2[31] = 1;
 284   s1[32] = 20;
 285   s2[32] = 20;
 286   s1[33] = -15;
 287   s2[33] = -15;
 288   s1[34] = -109;
 289   s2[34] = -109;
 290   s1[35] = 1;
 291   s2[35] = 1;
 292   s1[36] = 20;
 293   s2[36] = 20;
 294   s1[37] = -14;
 295   s2[37] = -14;
 296   s1[38] = -109;
 297   s2[38] = -109;
 298   s1[39] = 1;
 299   s2[39] = 1;
 300   s1[40] = 52;
 301   s2[40] = 52;
 302   s1[41] = -14;
 303   s2[41] = -14;
 304   s1[42] = -109;
 305   s2[42] = -109;
 306   s1[43] = 1;
 307   s2[43] = 1;
 308   s1[44] = 84;
 309   s2[44] = 84;
 310   s1[45] = -14;
 311   s2[45] = -14;
 312   s1[46] = -109;
 313   s2[46] = -109;
 314   s1[47] = 1;
 315   s2[47] = 1;
 316   s1[48] = 116;
 317   s2[48] = 116;
 318   s1[49] = -14;
 319   s2[49] = -14;
 320   s1[50] = -109;
 321   s2[50] = -109;
 322   s1[51] = 1;
 323   s2[51] = 1;
 324   s1[52] = 116;
 325   s2[52] = 116;
 326   s1[53] = -15;
 327   s2[53] = -15;
 328   s1[54] = -109;
 329   s2[54] = -109;
 330   s1[55] = 1;
 331   s2[55] = 1;
 332   s1[56] = -44;
 333   s2[56] = -44;
 334   s1[57] = -14;
 335   s2[57] = -14;
 336   s1[58] = -109;
 337   s2[58] = -109;
 338   s1[59] = 1;
 339   s2[59] = 1;
 340   s1[60] = -108;
 341   s2[60] = -108;
 342   s1[61] = -15;
 343   s2[61] = -15;
 344   s1[62] = -109;
 345   s2[62] = -109;
 346   s1[63] = 1;
 347   s2[63] = 1;
 348   s1[64] = -76;
 349   s2[64] = -76;
 350   s1[65] = -15;
 351   s2[65] = -15;
 352   s1[66] = -109;
 353   s2[66] = -109;
 354   s1[67] = 1;
 355   s2[67] = 1;
 356   s1[68] = -44;
 357   s2[68] = -44;
 358   s1[69] = -15;
 359   s2[69] = -15;
 360   s1[70] = -109;
 361   s2[70] = -109;
 362   s1[71] = 1;
 363   s2[71] = 1;
 364   s1[72] = -12;
 365   s2[72] = -12;
 366   s1[73] = -15;
 367   s2[73] = -15;
 368   s1[74] = -109;
 369   s2[74] = -109;
 370   s1[75] = 1;
 371   s2[75] = 1;
 372   s1[76] = -12;
 373   s2[76] = -12;
 374   s1[77] = -14;
 375   s2[77] = -14;
 376   s1[78] = -109;
 377   s2[78] = -109;
 378   s1[79] = 1;
 379   s2[79] = 1;
 380   s1[80] = 20;
 381   s2[80] = -68;
 382   s1[81] = -12;
 383   s2[81] = 64;
 384   s1[82] = -109;
 385   s2[82] = -106;
 386   s1[83] = 1;
 387   s2[83] = 1;
 388   s1[84] = -12;
 389   s2[84] = -12;
 390   s1[85] = -13;
 391   s2[85] = -13;
 392   s1[86] = -109;
 393   s2[86] = -109;
 394   s1[87] = 1;
 395   s2[87] = 1;
 396   s1[88] = -44;
 397   s2[88] = -44;
 398   s1[89] = -13;
 399   s2[89] = -13;
 400   s1[90] = -109;
 401   s2[90] = -109;
 402   s1[91] = 1;
 403   s2[91] = 1;
 404   s1[92] = -76;
 405   s2[92] = -76;
 406   s1[93] = -13;
 407   s2[93] = -13;
 408   s1[94] = -109;
 409   s2[94] = -109;
 410   s1[95] = 1;
 411   s2[95] = 1;
 412   s1[96] = -108;
 413   s2[96] = -108;
 414   s1[97] = -13;
 415   s2[97] = -13;
 416   s1[98] = -109;
 417   s2[98] = -109;
 418   s1[99] = 1;
 419   s2[99] = 1;
 420   s1[100] = 116;
 421   s2[100] = 116;
 422   s1[101] = CHAR__MIN;
 423   s2[101] = CHAR__MAX;
 424   s1[102] = -109;
 425   s2[102] = -109;
 426   s1[103] = 1;
 427   s2[103] = 1;
 428   s1[104] = 84;
 429   s2[104] = 84;
 430   s1[105] = -13;
 431   s2[105] = -13;
 432   s1[106] = -109;
 433   s2[106] = -109;
 434   s1[107] = 1;
 435   s2[107] = 1;
 436   s1[108] = 52;
 437   s2[108] = 52;
 438   s1[109] = -13;
 439   s2[109] = -13;
 440   s1[110] = -109;
 441   s2[110] = -109;
 442   s1[111] = 1;
 443   s2[111] = 1;
 444   s1[112] = CHAR__MAX;
 445   s2[112] = CHAR__MIN;
 446   s1[113] = -13;
 447   s2[113] = -13;
 448   s1[114] = -109;
 449   s2[114] = -109;
 450   s1[115] = 1;
 451   s2[115] = 1;
 452
 453   n = 116;
 454   for (size_t i = 0; i < n; i++)
 455     for (size_t len = 0; len <= n - i; ++len)
 456       {
 457         exp_result = SIMPLE_MEMCMP (s1 + i, s2 + i, len);
 458         FOR_EACH_IMPL (impl, 0)
 459           check_result (impl, s1 + i, s2 + i, len, exp_result);
 460       }
 461 }
 462
 463 /* This test checks that memcmp doesn't overrun buffers.  */
 464 static void
 465 check2 (void)
 466 {
 467   size_t max_length = page_size / sizeof (CHAR);
 468
 469   /* Initialize buf2 to the same values as buf1.  The bug requires the
 470      last compared byte to be different.  */
 471   memcpy (buf2, buf1, page_size);
 472   ((char *) buf2)[page_size - 1] ^= 0x11;
 473
 474   for (size_t length = 1; length < max_length; length++)
 475     {
 476       CHAR *s1 = (CHAR *) buf1 + max_length - length;
 477       CHAR *s2 = (CHAR *) buf2 + max_length - length;
 478
 479       const int exp_result = SIMPLE_MEMCMP (s1, s2, length);
 480
 481       FOR_EACH_IMPL (impl, 0)
 482         check_result (impl, s1, s2, length, exp_result);
 483     }
 484 }
 485
 486 int
 487 test_main (void)
 488 {
 489   size_t i;
 490
 491   test_init ();
 492
 493   check1 ();
 494   check2 ();
 495
 496   printf ("%23s", "");
 497   FOR_EACH_IMPL (impl, 0)
 498     printf ("\t%s", impl->name);
 499   putchar ('\n');
 500
 501   for (i = 1; i < 32; ++i)
 502     {
 503       do_test (i * CHARBYTES, i * CHARBYTES, i, 0);
 504       do_test (i * CHARBYTES, i * CHARBYTES, i, 1);
 505       do_test (i * CHARBYTES, i * CHARBYTES, i, -1);
 506     }
 507
 508   for (i = 0; i < 32; ++i)
 509     {
 510       do_test (0, 0, i, 0);
 511       do_test (0, 0, i, 1);
 512       do_test (0, 0, i, -1);
 513       do_test (4096 - i, 0, i, 0);
 514       do_test (4096 - i, 0, i, 1);
 515       do_test (4096 - i, 0, i, -1);
 516       do_test (4095, 0, i, 0);
 517       do_test (4095, 0, i, 1);
 518       do_test (4095, 0, i, -1);
 519       do_test (4095, 4095, i, 0);
 520       do_test (4095, 4095, i, 1);
 521       do_test (4095, 4095, i, -1);
 522       do_test (4000, 95, i, 0);
 523       do_test (4000, 95, i, 1);
 524       do_test (4000, 95, i, -1);
 525     }
 526
 527   for (i = 33; i < 385; i += 32)
 528     {
 529       do_test (0, 0, i, 0);
 530       do_test (0, 0, i, 1);
 531       do_test (0, 0, i, -1);
 532       do_test (i, 0, i, 0);
 533       do_test (0, i, i, 1);
 534       do_test (i, i, i, -1);
 535     }
 536
 537   for (i = 1; i < 10; ++i)
 538     {
 539       do_test (0, 0, 2 << i, 0);
 540       do_test (0, 0, 2 << i, 1);
 541       do_test (0, 0, 2 << i, -1);
 542       do_test ((8 - i) * CHARBYTES, (2 * i) * CHARBYTES, 16 << i, 0);
 543       do_test (0, 0, 16 << i, 0);
 544       do_test (0, 0, 16 << i, 1);
 545       do_test (0, 0, 16 << i, -1);
 546       do_test (i, 0, 2 << i, 0);
 547       do_test (0, i, 2 << i, 1);
 548       do_test (i, i, 2 << i, -1);
 549       do_test (i, 0, 16 << i, 0);
 550       do_test (0, i, 16 << i, 1);
 551       do_test (i, i, 16 << i, -1);
 552     }
 553
 554   for (i = 1; i < 10; ++i)
 555     {
 556       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 0);
 557       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 1);
 558       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, -1);
 559     }
 560
 561   do_random_tests ();
 562   return ret;
 563 }
 564
 565 #include <support/test-driver.c>