string/test-memcmp.c

   1 /* Test and measure memcmp functions.
   2    Copyright (C) 1999-2021 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 "wmemcmp"
  22 #else
  23 # define TEST_NAME "memcmp"
  24 #endif
  25 #include "test-string.h"
  26 #ifdef WIDE
  27 # include <inttypes.h>
  28 # include <wchar.h>
  29
  30 # define MEMCMP wmemcmp
  31 # define MEMCPY wmemcpy
  32 # define SIMPLE_MEMCMP simple_wmemcmp
  33 # define CHAR wchar_t
  34 # define UCHAR wchar_t
  35 # define CHARBYTES 4
  36 # define CHAR__MIN WCHAR_MIN
  37 # define CHAR__MAX WCHAR_MAX
  38 int
  39 simple_wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
  40 {
  41   int ret = 0;
  42   /* Warning!
  43         wmemcmp has to use SIGNED comparison for elements.
  44         memcmp has to use UNSIGNED comparison for elemnts.
  45   */
  46   while (n-- && (ret = *s1 < *s2 ? -1 : *s1 == *s2 ? 0 : 1) == 0) {s1++; s2++;}
  47   return ret;
  48 }
  49 #else
  50 # include <limits.h>
  51
  52 # define MEMCMP memcmp
  53 # define MEMCPY memcpy
  54 # define SIMPLE_MEMCMP simple_memcmp
  55 # define CHAR char
  56 # define MAX_CHAR 255
  57 # define UCHAR unsigned char
  58 # define CHARBYTES 1
  59 # define CHAR__MIN CHAR_MIN
  60 # define CHAR__MAX CHAR_MAX
  61
  62 int
  63 simple_memcmp (const char *s1, const char *s2, size_t n)
  64 {
  65   int ret = 0;
  66
  67   while (n-- && (ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) == 0);
  68   return ret;
  69 }
  70 #endif
  71
  72 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
  73
  74 IMPL (SIMPLE_MEMCMP, 0)
  75 IMPL (MEMCMP, 1)
  76
  77 static int
  78 check_result (impl_t *impl, const CHAR *s1, const CHAR *s2, size_t len,
  79               int exp_result)
  80 {
  81   int result = CALL (impl, s1, s2, len);
  82   if ((exp_result == 0 && result != 0)
  83       || (exp_result < 0 && result >= 0)
  84       || (exp_result > 0 && result <= 0))
  85     {
  86       error (0, 0, "Wrong result in function %s %d %d", impl->name,
  87              result, exp_result);
  88       ret = 1;
  89       return -1;
  90     }
  91
  92   return 0;
  93 }
  94
  95 static void
  96 do_one_test (impl_t *impl, const CHAR *s1, const CHAR *s2, size_t len,
  97              int exp_result)
  98 {
  99   if (check_result (impl, s1, s2, len, exp_result) < 0)
 100     return;
 101 }
 102
 103 static void
 104 do_test (size_t align1, size_t align2, size_t len, int exp_result)
 105 {
 106   size_t i;
 107   CHAR *s1, *s2;
 108
 109   if (len == 0)
 110     return;
 111
 112   align1 &= (4096 - CHARBYTES);
 113   if (align1 + (len + 1) * CHARBYTES >= page_size)
 114     return;
 115
 116   align2 &= (4096 - CHARBYTES);
 117   if (align2 + (len + 1) * CHARBYTES >= page_size)
 118     return;
 119
 120   s1 = (CHAR *) (buf1 + align1);
 121   s2 = (CHAR *) (buf2 + align2);
 122
 123   for (i = 0; i < len; i++)
 124     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % CHAR__MAX;
 125
 126   s1[len] = align1;
 127   s2[len] = align2;
 128   s2[len - 1] -= exp_result;
 129
 130   FOR_EACH_IMPL (impl, 0)
 131     do_one_test (impl, s1, s2, len, exp_result);
 132 }
 133
 134 static void
 135 do_random_tests (void)
 136 {
 137   size_t i, j, n, align1, align2, pos, len;
 138   int result;
 139   long r;
 140   UCHAR *p1 =  (UCHAR *) (buf1 + page_size - 512 * CHARBYTES);
 141   UCHAR *p2 =  (UCHAR *) (buf2 + page_size - 512 * CHARBYTES);
 142
 143   for (n = 0; n < ITERATIONS; n++)
 144     {
 145    align1 = random () & 31;
 146       if (random () & 1)
 147         align2 = random () & 31;
 148       else
 149         align2 = align1 + (random () & 24);
 150       pos = random () & 511;
 151       j = align1;
 152       if (align2 > j)
 153         j = align2;
 154       if (pos + j >= 512)
 155         pos = 511 - j - (random () & 7);
 156       len = random () & 511;
 157       if (len + j >= 512)
 158         len = 511 - j - (random () & 7);
 159       j = len + align1 + 64;
 160       if (j > 512) j = 512;
 161       for (i = 0; i < j; ++i)
 162         p1[i] = random () & 255;
 163       for (i = 0; i < j; ++i)
 164         p2[i] = random () & 255;
 165
 166       result = 0;
 167       if (pos >= len)
 168         MEMCPY ((CHAR *) p2 + align2, (const CHAR *) p1 + align1, len);
 169       else
 170         {
 171           MEMCPY ((CHAR *) p2 + align2, (const CHAR *) p1 + align1, pos);
 172           if (p2[align2 + pos] == p1[align1 + pos])
 173             {
 174               p2[align2 + pos] = random () & 255;
 175               if (p2[align2 + pos] == p1[align1 + pos])
 176                 p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
 177             }
 178
 179           if (p1[align1 + pos] < p2[align2 + pos])
 180             result = -1;
 181           else
 182             result = 1;
 183         }
 184
 185       FOR_EACH_IMPL (impl, 1)
 186         {
 187           r = CALL (impl, (CHAR *) p1 + align1, (const CHAR *) p2 + align2,
 188                     len);
 189           if ((r == 0 && result)
 190               || (r < 0 && result >= 0)
 191               || (r > 0 && result <= 0))
 192             {
 193               error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %zd, %zd, %zd) %ld != %d, p1 %p p2 %p",
 194                      n, impl->name, align1 * CHARBYTES & 63,  align2 * CHARBYTES & 63, len, pos, r, result, p1, p2);
 195               ret = 1;
 196             }
 197         }
 198     }
 199 }
 200
 201 static void
 202 check1 (void)
 203 {
 204   CHAR s1[116], s2[116];
 205   int n, exp_result;
 206
 207   s1[0] = -108;
 208   s2[0] = -108;
 209   s1[1] = 99;
 210   s2[1] = 99;
 211   s1[2] = -113;
 212   s2[2] = -113;
 213   s1[3] = 1;
 214   s2[3] = 1;
 215   s1[4] = 116;
 216   s2[4] = 116;
 217   s1[5] = 99;
 218   s2[5] = 99;
 219   s1[6] = -113;
 220   s2[6] = -113;
 221   s1[7] = 1;
 222   s2[7] = 1;
 223   s1[8] = 84;
 224   s2[8] = 84;
 225   s1[9] = 99;
 226   s2[9] = 99;
 227   s1[10] = -113;
 228   s2[10] = -113;
 229   s1[11] = 1;
 230   s2[11] = 1;
 231   s1[12] = 52;
 232   s2[12] = 52;
 233   s1[13] = 99;
 234   s2[13] = 99;
 235   s1[14] = -113;
 236   s2[14] = -113;
 237   s1[15] = 1;
 238   s2[15] = 1;
 239   s1[16] = -76;
 240   s2[16] = -76;
 241   s1[17] = -14;
 242   s2[17] = -14;
 243   s1[18] = -109;
 244   s2[18] = -109;
 245   s1[19] = 1;
 246   s2[19] = 1;
 247   s1[20] = -108;
 248   s2[20] = -108;
 249   s1[21] = -14;
 250   s2[21] = -14;
 251   s1[22] = -109;
 252   s2[22] = -109;
 253   s1[23] = 1;
 254   s2[23] = 1;
 255   s1[24] = 84;
 256   s2[24] = 84;
 257   s1[25] = -15;
 258   s2[25] = -15;
 259   s1[26] = -109;
 260   s2[26] = -109;
 261   s1[27] = 1;
 262   s2[27] = 1;
 263   s1[28] = 52;
 264   s2[28] = 52;
 265   s1[29] = -15;
 266   s2[29] = -15;
 267   s1[30] = -109;
 268   s2[30] = -109;
 269   s1[31] = 1;
 270   s2[31] = 1;
 271   s1[32] = 20;
 272   s2[32] = 20;
 273   s1[33] = -15;
 274   s2[33] = -15;
 275   s1[34] = -109;
 276   s2[34] = -109;
 277   s1[35] = 1;
 278   s2[35] = 1;
 279   s1[36] = 20;
 280   s2[36] = 20;
 281   s1[37] = -14;
 282   s2[37] = -14;
 283   s1[38] = -109;
 284   s2[38] = -109;
 285   s1[39] = 1;
 286   s2[39] = 1;
 287   s1[40] = 52;
 288   s2[40] = 52;
 289   s1[41] = -14;
 290   s2[41] = -14;
 291   s1[42] = -109;
 292   s2[42] = -109;
 293   s1[43] = 1;
 294   s2[43] = 1;
 295   s1[44] = 84;
 296   s2[44] = 84;
 297   s1[45] = -14;
 298   s2[45] = -14;
 299   s1[46] = -109;
 300   s2[46] = -109;
 301   s1[47] = 1;
 302   s2[47] = 1;
 303   s1[48] = 116;
 304   s2[48] = 116;
 305   s1[49] = -14;
 306   s2[49] = -14;
 307   s1[50] = -109;
 308   s2[50] = -109;
 309   s1[51] = 1;
 310   s2[51] = 1;
 311   s1[52] = 116;
 312   s2[52] = 116;
 313   s1[53] = -15;
 314   s2[53] = -15;
 315   s1[54] = -109;
 316   s2[54] = -109;
 317   s1[55] = 1;
 318   s2[55] = 1;
 319   s1[56] = -44;
 320   s2[56] = -44;
 321   s1[57] = -14;
 322   s2[57] = -14;
 323   s1[58] = -109;
 324   s2[58] = -109;
 325   s1[59] = 1;
 326   s2[59] = 1;
 327   s1[60] = -108;
 328   s2[60] = -108;
 329   s1[61] = -15;
 330   s2[61] = -15;
 331   s1[62] = -109;
 332   s2[62] = -109;
 333   s1[63] = 1;
 334   s2[63] = 1;
 335   s1[64] = -76;
 336   s2[64] = -76;
 337   s1[65] = -15;
 338   s2[65] = -15;
 339   s1[66] = -109;
 340   s2[66] = -109;
 341   s1[67] = 1;
 342   s2[67] = 1;
 343   s1[68] = -44;
 344   s2[68] = -44;
 345   s1[69] = -15;
 346   s2[69] = -15;
 347   s1[70] = -109;
 348   s2[70] = -109;
 349   s1[71] = 1;
 350   s2[71] = 1;
 351   s1[72] = -12;
 352   s2[72] = -12;
 353   s1[73] = -15;
 354   s2[73] = -15;
 355   s1[74] = -109;
 356   s2[74] = -109;
 357   s1[75] = 1;
 358   s2[75] = 1;
 359   s1[76] = -12;
 360   s2[76] = -12;
 361   s1[77] = -14;
 362   s2[77] = -14;
 363   s1[78] = -109;
 364   s2[78] = -109;
 365   s1[79] = 1;
 366   s2[79] = 1;
 367   s1[80] = 20;
 368   s2[80] = -68;
 369   s1[81] = -12;
 370   s2[81] = 64;
 371   s1[82] = -109;
 372   s2[82] = -106;
 373   s1[83] = 1;
 374   s2[83] = 1;
 375   s1[84] = -12;
 376   s2[84] = -12;
 377   s1[85] = -13;
 378   s2[85] = -13;
 379   s1[86] = -109;
 380   s2[86] = -109;
 381   s1[87] = 1;
 382   s2[87] = 1;
 383   s1[88] = -44;
 384   s2[88] = -44;
 385   s1[89] = -13;
 386   s2[89] = -13;
 387   s1[90] = -109;
 388   s2[90] = -109;
 389   s1[91] = 1;
 390   s2[91] = 1;
 391   s1[92] = -76;
 392   s2[92] = -76;
 393   s1[93] = -13;
 394   s2[93] = -13;
 395   s1[94] = -109;
 396   s2[94] = -109;
 397   s1[95] = 1;
 398   s2[95] = 1;
 399   s1[96] = -108;
 400   s2[96] = -108;
 401   s1[97] = -13;
 402   s2[97] = -13;
 403   s1[98] = -109;
 404   s2[98] = -109;
 405   s1[99] = 1;
 406   s2[99] = 1;
 407   s1[100] = 116;
 408   s2[100] = 116;
 409   s1[101] = CHAR__MIN;
 410   s2[101] = CHAR__MAX;
 411   s1[102] = -109;
 412   s2[102] = -109;
 413   s1[103] = 1;
 414   s2[103] = 1;
 415   s1[104] = 84;
 416   s2[104] = 84;
 417   s1[105] = -13;
 418   s2[105] = -13;
 419   s1[106] = -109;
 420   s2[106] = -109;
 421   s1[107] = 1;
 422   s2[107] = 1;
 423   s1[108] = 52;
 424   s2[108] = 52;
 425   s1[109] = -13;
 426   s2[109] = -13;
 427   s1[110] = -109;
 428   s2[110] = -109;
 429   s1[111] = 1;
 430   s2[111] = 1;
 431   s1[112] = CHAR__MAX;
 432   s2[112] = CHAR__MIN;
 433   s1[113] = -13;
 434   s2[113] = -13;
 435   s1[114] = -109;
 436   s2[114] = -109;
 437   s1[115] = 1;
 438   s2[115] = 1;
 439
 440   n = 116;
 441   for (size_t i = 0; i < n; i++)
 442     for (size_t len = 0; len <= n - i; ++len)
 443       {
 444         exp_result = SIMPLE_MEMCMP (s1 + i, s2 + i, len);
 445         FOR_EACH_IMPL (impl, 0)
 446           check_result (impl, s1 + i, s2 + i, len, exp_result);
 447       }
 448 }
 449
 450 /* This test checks that memcmp doesn't overrun buffers.  */
 451 static void
 452 check2 (void)
 453 {
 454   size_t max_length = page_size / sizeof (CHAR);
 455
 456   /* Initialize buf2 to the same values as buf1.  The bug requires the
 457      last compared byte to be different.  */
 458   memcpy (buf2, buf1, page_size);
 459   ((char *) buf2)[page_size - 1] ^= 0x11;
 460
 461   for (size_t length = 1; length < max_length; length++)
 462     {
 463       CHAR *s1 = (CHAR *) buf1 + max_length - length;
 464       CHAR *s2 = (CHAR *) buf2 + max_length - length;
 465
 466       const int exp_result = SIMPLE_MEMCMP (s1, s2, length);
 467
 468       FOR_EACH_IMPL (impl, 0)
 469         check_result (impl, s1, s2, length, exp_result);
 470     }
 471 }
 472
 473 int
 474 test_main (void)
 475 {
 476   size_t i;
 477
 478   test_init ();
 479
 480   check1 ();
 481   check2 ();
 482
 483   printf ("%23s", "");
 484   FOR_EACH_IMPL (impl, 0)
 485     printf ("\t%s", impl->name);
 486   putchar ('\n');
 487
 488   for (i = 1; i < 32; ++i)
 489     {
 490       do_test (i * CHARBYTES, i * CHARBYTES, i, 0);
 491       do_test (i * CHARBYTES, i * CHARBYTES, i, 1);
 492       do_test (i * CHARBYTES, i * CHARBYTES, i, -1);
 493     }
 494
 495   for (i = 0; i < 32; ++i)
 496     {
 497       do_test (0, 0, i, 0);
 498       do_test (0, 0, i, 1);
 499       do_test (0, 0, i, -1);
 500       do_test (4096 - i, 0, i, 0);
 501       do_test (4096 - i, 0, i, 1);
 502       do_test (4096 - i, 0, i, -1);
 503       do_test (4095, 0, i, 0);
 504       do_test (4095, 0, i, 1);
 505       do_test (4095, 0, i, -1);
 506       do_test (4095, 4095, i, 0);
 507       do_test (4095, 4095, i, 1);
 508       do_test (4095, 4095, i, -1);
 509       do_test (4000, 95, i, 0);
 510       do_test (4000, 95, i, 1);
 511       do_test (4000, 95, i, -1);
 512     }
 513
 514   for (i = 33; i < 385; i += 32)
 515     {
 516       do_test (0, 0, i, 0);
 517       do_test (0, 0, i, 1);
 518       do_test (0, 0, i, -1);
 519       do_test (i, 0, i, 0);
 520       do_test (0, i, i, 1);
 521       do_test (i, i, i, -1);
 522     }
 523
 524   for (i = 1; i < 10; ++i)
 525     {
 526       do_test (0, 0, 2 << i, 0);
 527       do_test (0, 0, 2 << i, 1);
 528       do_test (0, 0, 2 << i, -1);
 529       do_test ((8 - i) * CHARBYTES, (2 * i) * CHARBYTES, 16 << i, 0);
 530       do_test (0, 0, 16 << i, 0);
 531       do_test (0, 0, 16 << i, 1);
 532       do_test (0, 0, 16 << i, -1);
 533       do_test (i, 0, 2 << i, 0);
 534       do_test (0, i, 2 << i, 1);
 535       do_test (i, i, 2 << i, -1);
 536       do_test (i, 0, 16 << i, 0);
 537       do_test (0, i, 16 << i, 1);
 538       do_test (i, i, 16 << i, -1);
 539     }
 540
 541   for (i = 1; i < 10; ++i)
 542     {
 543       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 0);
 544       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 1);
 545       do_test (i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, -1);
 546     }
 547
 548   do_random_tests ();
 549   return ret;
 550 }
 551
 552 #include <support/test-driver.c>