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

source code of glibc/string/test-memcmp.c