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