string/test-strncmp.c

   1 /* Test and measure strncmp functions.
   2    Copyright (C) 1999-2012 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Written by Jakub Jelinek <jakub@redhat.com>, 1999.
   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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #define TEST_MAIN
  21 #define TEST_NAME "strncmp"
  22 #include "test-string.h"
  23
  24 typedef int (*proto_t) (const char *, const char *, size_t);
  25 int simple_strncmp (const char *, const char *, size_t);
  26 int stupid_strncmp (const char *, const char *, size_t);
  27
  28 IMPL (stupid_strncmp, 0)
  29 IMPL (simple_strncmp, 0)
  30 IMPL (strncmp, 1)
  31
  32 int
  33 simple_strncmp (const char *s1, const char *s2, size_t n)
  34 {
  35   int ret = 0;
  36
  37   while (n-- && (ret = *(unsigned char *) s1 - * (unsigned char *) s2++) == 0
  38          && *s1++);
  39   return ret;
  40 }
  41
  42 int
  43 stupid_strncmp (const char *s1, const char *s2, size_t n)
  44 {
  45   size_t ns1 = strnlen (s1, n) + 1, ns2 = strnlen (s2, n) + 1;
  46   int ret = 0;
  47
  48   n = ns1 < n ? ns1 : n;
  49   n = ns2 < n ? ns2 : n;
  50   while (n-- && (ret = *(unsigned char *) s1++ - * (unsigned char *) s2++) == 0);
  51   return ret;
  52 }
  53
  54 static int
  55 check_result (impl_t *impl, const char *s1, const char *s2, size_t n,
  56              int exp_result)
  57 {
  58   int result = CALL (impl, s1, s2, n);
  59   if ((exp_result == 0 && result != 0)
  60       || (exp_result < 0 && result >= 0)
  61       || (exp_result > 0 && result <= 0))
  62     {
  63       error (0, 0, "Wrong result in function %s %d %d", impl->name,
  64              result, exp_result);
  65       ret = 1;
  66       return -1;
  67     }
  68
  69   return 0;
  70 }
  71
  72 static void
  73 do_one_test (impl_t *impl, const char *s1, const char *s2, size_t n,
  74              int exp_result)
  75 {
  76   if (check_result (impl, s1, s2, n, exp_result) < 0)
  77     return;
  78
  79   if (HP_TIMING_AVAIL)
  80     {
  81       hp_timing_t start __attribute ((unused));
  82       hp_timing_t stop __attribute ((unused));
  83       hp_timing_t best_time = ~ (hp_timing_t) 0;
  84       size_t i;
  85
  86       for (i = 0; i < 32; ++i)
  87         {
  88           HP_TIMING_NOW (start);
  89           CALL (impl, s1, s2, n);
  90           HP_TIMING_NOW (stop);
  91           HP_TIMING_BEST (best_time, start, stop);
  92         }
  93
  94       printf ("\t%zd", (size_t) best_time);
  95     }
  96 }
  97
  98 static void
  99 do_test_limit (size_t align1, size_t align2, size_t len, size_t n, int max_char,
 100          int exp_result)
 101 {
 102   size_t i, align_n;
 103   char *s1, *s2;
 104
 105   if (n == 0)
 106     {
 107       s1 = (char*)(buf1 + page_size);
 108       s2 = (char*)(buf2 + page_size);
 109       if (HP_TIMING_AVAIL)
 110         printf ("Length %4zd/%4zd:", len, n);
 111
 112       FOR_EACH_IMPL (impl, 0)
 113         do_one_test (impl, s1, s2, n, 0);
 114
 115       if (HP_TIMING_AVAIL)
 116         putchar ('\n');
 117
 118       return;
 119     }
 120
 121   align1 &= 15;
 122   align2 &= 15;
 123   align_n = (page_size - n) & 15;
 124
 125   s1 = (char*)(buf1 + page_size - n);
 126   s2 = (char*)(buf2 + page_size - n);
 127
 128   if (align1 < align_n)
 129     s1 -= (align_n - align1);
 130
 131   if (align2 < align_n)
 132     s2 -= (align_n - align2);
 133
 134   for (i = 0; i < n; i++)
 135     s1[i] = s2[i] = 1 + 23 * i % max_char;
 136
 137   if (len < n)
 138     {
 139       s1[len] = 0;
 140       s2[len] = 0;
 141       if (exp_result < 0)
 142         s2[len] = 32;
 143       else if (exp_result > 0)
 144         s1[len] = 64;
 145     }
 146
 147   if (HP_TIMING_AVAIL)
 148     printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2);
 149
 150   FOR_EACH_IMPL (impl, 0)
 151     do_one_test (impl, s1, s2, n, exp_result);
 152
 153   if (HP_TIMING_AVAIL)
 154     putchar ('\n');
 155 }
 156
 157 static void
 158 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char,
 159          int exp_result)
 160 {
 161   size_t i;
 162   char *s1, *s2;
 163
 164   if (n == 0)
 165     return;
 166
 167   align1 &= 7;
 168   if (align1 + n + 1 >= page_size)
 169     return;
 170
 171   align2 &= 7;
 172   if (align2 + n + 1 >= page_size)
 173     return;
 174
 175   s1 = (char*)(buf1 + align1);
 176   s2 = (char*)(buf2 + align2);
 177
 178   for (i = 0; i < n; i++)
 179     s1[i] = s2[i] = 1 + 23 * i % max_char;
 180
 181   s1[n] = 24 + exp_result;
 182   s2[n] = 23;
 183   s1[len] = 0;
 184   s2[len] = 0;
 185   if (exp_result < 0)
 186     s2[len] = 32;
 187   else if (exp_result > 0)
 188     s1[len] = 64;
 189   if (len >= n)
 190     s2[n - 1] -= exp_result;
 191
 192   if (HP_TIMING_AVAIL)
 193     printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2);
 194
 195   FOR_EACH_IMPL (impl, 0)
 196     do_one_test (impl, (char*)s1, (char*)s2, n, exp_result);
 197
 198   if (HP_TIMING_AVAIL)
 199     putchar ('\n');
 200 }
 201
 202 static void
 203 do_page_test (size_t offset1, size_t offset2, char *s2)
 204 {
 205   char *s1;
 206   int exp_result;
 207
 208   if (offset1 >= page_size || offset2 >= page_size)
 209     return;
 210
 211   s1 = (char *) (buf1 + offset1);
 212   s2 += offset2;
 213
 214   exp_result= *s1;
 215
 216   FOR_EACH_IMPL (impl, 0)
 217     {
 218       check_result (impl, s1, s2, page_size, -exp_result);
 219       check_result (impl, s2, s1, page_size, exp_result);
 220     }
 221 }
 222
 223 static void
 224 do_random_tests (void)
 225 {
 226   size_t i, j, n, align1, align2, pos, len1, len2, size;
 227   int result;
 228   long r;
 229   unsigned char *p1 = buf1 + page_size - 512;
 230   unsigned char *p2 = buf2 + page_size - 512;
 231
 232   for (n = 0; n < ITERATIONS; n++)
 233     {
 234       align1 = random () & 31;
 235       if (random () & 1)
 236         align2 = random () & 31;
 237       else
 238         align2 = align1 + (random () & 24);
 239       pos = random () & 511;
 240       size = random () & 511;
 241       j = align1 > align2 ? align1 : align2;
 242       if (pos + j >= 511)
 243         pos = 510 - j - (random () & 7);
 244       len1 = random () & 511;
 245       if (pos >= len1 && (random () & 1))
 246         len1 = pos + (random () & 7);
 247       if (len1 + j >= 512)
 248         len1 = 511 - j - (random () & 7);
 249       if (pos >= len1)
 250         len2 = len1;
 251       else
 252         len2 = len1 + (len1 != 511 - j ? random () % (511 - j - len1) : 0);
 253       j = (pos > len2 ? pos : len2) + align1 + 64;
 254       if (j > 512)
 255         j = 512;
 256       for (i = 0; i < j; ++i)
 257         {
 258           p1[i] = random () & 255;
 259           if (i < len1 + align1 && !p1[i])
 260             {
 261               p1[i] = random () & 255;
 262               if (!p1[i])
 263                 p1[i] = 1 + (random () & 127);
 264             }
 265         }
 266       for (i = 0; i < j; ++i)
 267         {
 268           p2[i] = random () & 255;
 269           if (i < len2 + align2 && !p2[i])
 270             {
 271               p2[i] = random () & 255;
 272               if (!p2[i])
 273                 p2[i] = 1 + (random () & 127);
 274             }
 275         }
 276
 277       result = 0;
 278       memcpy (p2 + align2, p1 + align1, pos);
 279       if (pos < len1)
 280         {
 281           if (p2[align2 + pos] == p1[align1 + pos])
 282             {
 283               p2[align2 + pos] = random () & 255;
 284               if (p2[align2 + pos] == p1[align1 + pos])
 285                 p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
 286             }
 287
 288           if (pos < size)
 289             {
 290               if (p1[align1 + pos] < p2[align2 + pos])
 291                 result = -1;
 292               else
 293                 result = 1;
 294             }
 295         }
 296       p1[len1 + align1] = 0;
 297       p2[len2 + align2] = 0;
 298
 299       FOR_EACH_IMPL (impl, 1)
 300         {
 301           r = CALL (impl, (char*)(p1 + align1), (char*)(p2 + align2), size);
 302           /* Test whether on 64-bit architectures where ABI requires
 303              callee to promote has the promotion been done.  */
 304           asm ("" : "=g" (r) : "0" (r));
 305           if ((r == 0 && result)
 306               || (r < 0 && result >= 0)
 307               || (r > 0 && result <= 0))
 308             {
 309               error (0, 0, "Iteration %zd - wrong result in function %s (%zd, %zd, %zd, %zd, %zd, %zd) %ld != %d, p1 %p p2 %p",
 310                      n, impl->name, align1, align2, len1, len2, pos, size, r, result, p1, p2);
 311               ret = 1;
 312             }
 313         }
 314     }
 315 }
 316
 317 static void
 318 check1 (void)
 319 {
 320   char *s1 = (char *)(buf1 + 0xb2c);
 321   char *s2 = (char *)(buf1 + 0xfd8);
 322   size_t i;
 323   int exp_result;
 324
 325   strcpy(s1, "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrs");
 326   strcpy(s2, "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkLMNOPQRSTUV");
 327
 328   for (i = 0; i < 80; i++)
 329     {
 330       exp_result = simple_strncmp (s1, s2, i);
 331       FOR_EACH_IMPL (impl, 0)
 332          check_result (impl, s1, s2, i, exp_result);
 333     }
 334 }
 335
 336 static void
 337 check2 (void)
 338 {
 339   size_t i;
 340   char *s1, *s2;
 341
 342   s1 = (char *) buf1;
 343   for (i = 0; i < page_size - 1; i++)
 344     s1[i] = 23;
 345   s1[i] = 0;
 346
 347   s2 = strdup (s1);
 348
 349   for (i = 0; i < 64; ++i)
 350     do_page_test (3990 + i, 2635, s2);
 351
 352   free (s2);
 353 }
 354
 355 int
 356 test_main (void)
 357 {
 358   size_t i;
 359
 360   test_init ();
 361
 362   check1 ();
 363   check2 ();
 364
 365   printf ("%23s", "");
 366   FOR_EACH_IMPL (impl, 0)
 367     printf ("\t%s", impl->name);
 368   putchar ('\n');
 369
 370   for (i =0; i < 16; ++i)
 371     {
 372       do_test (0, 0, 8, i, 127, 0);
 373       do_test (0, 0, 8, i, 127, -1);
 374       do_test (0, 0, 8, i, 127, 1);
 375       do_test (i, i, 8, i, 127, 0);
 376       do_test (i, i, 8, i, 127, 1);
 377       do_test (i, i, 8, i, 127, -1);
 378       do_test (i, 2 * i, 8, i, 127, 0);
 379       do_test (2 * i, i, 8, i, 127, 1);
 380       do_test (i, 3 * i, 8, i, 127, -1);
 381       do_test (0, 0, 8, i, 255, 0);
 382       do_test (0, 0, 8, i, 255, -1);
 383       do_test (0, 0, 8, i, 255, 1);
 384       do_test (i, i, 8, i, 255, 0);
 385       do_test (i, i, 8, i, 255, 1);
 386       do_test (i, i, 8, i, 255, -1);
 387       do_test (i, 2 * i, 8, i, 255, 0);
 388       do_test (2 * i, i, 8, i, 255, 1);
 389       do_test (i, 3 * i, 8, i, 255, -1);
 390     }
 391
 392   for (i = 1; i < 8; ++i)
 393     {
 394       do_test (0, 0, 8 << i, 16 << i, 127, 0);
 395       do_test (0, 0, 8 << i, 16 << i, 127, 1);
 396       do_test (0, 0, 8 << i, 16 << i, 127, -1);
 397       do_test (0, 0, 8 << i, 16 << i, 255, 0);
 398       do_test (0, 0, 8 << i, 16 << i, 255, 1);
 399       do_test (0, 0, 8 << i, 16 << i, 255, -1);
 400       do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 0);
 401       do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 1);
 402       do_test (2 * i, i, 8 << i, 16 << i, 255, 0);
 403       do_test (2 * i, i, 8 << i, 16 << i, 255, 1);
 404     }
 405
 406   do_test_limit (0, 0, 0, 0, 127, 0);
 407   do_test_limit (4, 0, 21, 20, 127, 0);
 408   do_test_limit (0, 4, 21, 20, 127, 0);
 409   do_test_limit (8, 0, 25, 24, 127, 0);
 410   do_test_limit (0, 8, 25, 24, 127, 0);
 411
 412   for (i = 0; i < 8; ++i)
 413     {
 414       do_test_limit (0, 0, 17 - i, 16 - i, 127, 0);
 415       do_test_limit (0, 0, 17 - i, 16 - i, 255, 0);
 416       do_test_limit (0, 0, 15 - i, 16 - i, 127, 0);
 417       do_test_limit (0, 0, 15 - i, 16 - i, 127, 1);
 418       do_test_limit (0, 0, 15 - i, 16 - i, 127, -1);
 419       do_test_limit (0, 0, 15 - i, 16 - i, 255, 0);
 420       do_test_limit (0, 0, 15 - i, 16 - i, 255, 1);
 421       do_test_limit (0, 0, 15 - i, 16 - i, 255, -1);
 422     }
 423
 424   do_random_tests ();
 425   return ret;
 426 }
 427
 428 #include "../test-skeleton.c"