1 /* Test and measure memcmp functions.
2 Copyright (C) 1999-2023 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>