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23#include <linux/types.h>
24#include <linux/string.h>
25#include <linux/ctype.h>
26#include <linux/kernel.h>
27#include <linux/export.h>
28#include <linux/bug.h>
29#include <linux/errno.h>
30
31#include <asm/byteorder.h>
32#include <asm/word-at-a-time.h>
33#include <asm/page.h>
34
35#ifndef __HAVE_ARCH_STRNCASECMP
36
37
38
39
40
41
42int strncasecmp(const char *s1, const char *s2, size_t len)
43{
44
45 unsigned char c1, c2;
46
47 if (!len)
48 return 0;
49
50 do {
51 c1 = *s1++;
52 c2 = *s2++;
53 if (!c1 || !c2)
54 break;
55 if (c1 == c2)
56 continue;
57 c1 = tolower(c1);
58 c2 = tolower(c2);
59 if (c1 != c2)
60 break;
61 } while (--len);
62 return (int)c1 - (int)c2;
63}
64EXPORT_SYMBOL(strncasecmp);
65#endif
66
67#ifndef __HAVE_ARCH_STRCASECMP
68int strcasecmp(const char *s1, const char *s2)
69{
70 int c1, c2;
71
72 do {
73 c1 = tolower(*s1++);
74 c2 = tolower(*s2++);
75 } while (c1 == c2 && c1 != 0);
76 return c1 - c2;
77}
78EXPORT_SYMBOL(strcasecmp);
79#endif
80
81#ifndef __HAVE_ARCH_STRCPY
82
83
84
85
86
87#undef strcpy
88char *strcpy(char *dest, const char *src)
89{
90 char *tmp = dest;
91
92 while ((*dest++ = *src++) != '\0')
93 ;
94 return tmp;
95}
96EXPORT_SYMBOL(strcpy);
97#endif
98
99#ifndef __HAVE_ARCH_STRNCPY
100
101
102
103
104
105
106
107
108
109
110
111
112
113char *strncpy(char *dest, const char *src, size_t count)
114{
115 char *tmp = dest;
116
117 while (count) {
118 if ((*tmp = *src) != 0)
119 src++;
120 tmp++;
121 count--;
122 }
123 return dest;
124}
125EXPORT_SYMBOL(strncpy);
126#endif
127
128#ifndef __HAVE_ARCH_STRLCPY
129
130
131
132
133
134
135
136
137
138
139
140size_t strlcpy(char *dest, const char *src, size_t size)
141{
142 size_t ret = strlen(src);
143
144 if (size) {
145 size_t len = (ret >= size) ? size - 1 : ret;
146 memcpy(dest, src, len);
147 dest[len] = '\0';
148 }
149 return ret;
150}
151EXPORT_SYMBOL(strlcpy);
152#endif
153
154#ifndef __HAVE_ARCH_STRSCPY
155
156
157
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159
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161
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163
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176
177
178ssize_t strscpy(char *dest, const char *src, size_t count)
179{
180 const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
181 size_t max = count;
182 long res = 0;
183
184 if (count == 0)
185 return -E2BIG;
186
187#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
188
189
190
191
192 if ((long)src & (sizeof(long) - 1)) {
193 size_t limit = PAGE_SIZE - ((long)src & (PAGE_SIZE - 1));
194 if (limit < max)
195 max = limit;
196 }
197#else
198
199 if (((long) dest | (long) src) & (sizeof(long) - 1))
200 max = 0;
201#endif
202
203 while (max >= sizeof(unsigned long)) {
204 unsigned long c, data;
205
206 c = read_word_at_a_time(src+res);
207 if (has_zero(c, &data, &constants)) {
208 data = prep_zero_mask(c, data, &constants);
209 data = create_zero_mask(data);
210 *(unsigned long *)(dest+res) = c & zero_bytemask(data);
211 return res + find_zero(data);
212 }
213 *(unsigned long *)(dest+res) = c;
214 res += sizeof(unsigned long);
215 count -= sizeof(unsigned long);
216 max -= sizeof(unsigned long);
217 }
218
219 while (count) {
220 char c;
221
222 c = src[res];
223 dest[res] = c;
224 if (!c)
225 return res;
226 res++;
227 count--;
228 }
229
230
231 if (res)
232 dest[res-1] = '\0';
233
234 return -E2BIG;
235}
236EXPORT_SYMBOL(strscpy);
237#endif
238
239#ifndef __HAVE_ARCH_STRCAT
240
241
242
243
244
245#undef strcat
246char *strcat(char *dest, const char *src)
247{
248 char *tmp = dest;
249
250 while (*dest)
251 dest++;
252 while ((*dest++ = *src++) != '\0')
253 ;
254 return tmp;
255}
256EXPORT_SYMBOL(strcat);
257#endif
258
259#ifndef __HAVE_ARCH_STRNCAT
260
261
262
263
264
265
266
267
268
269char *strncat(char *dest, const char *src, size_t count)
270{
271 char *tmp = dest;
272
273 if (count) {
274 while (*dest)
275 dest++;
276 while ((*dest++ = *src++) != 0) {
277 if (--count == 0) {
278 *dest = '\0';
279 break;
280 }
281 }
282 }
283 return tmp;
284}
285EXPORT_SYMBOL(strncat);
286#endif
287
288#ifndef __HAVE_ARCH_STRLCAT
289
290
291
292
293
294
295size_t strlcat(char *dest, const char *src, size_t count)
296{
297 size_t dsize = strlen(dest);
298 size_t len = strlen(src);
299 size_t res = dsize + len;
300
301
302 BUG_ON(dsize >= count);
303
304 dest += dsize;
305 count -= dsize;
306 if (len >= count)
307 len = count-1;
308 memcpy(dest, src, len);
309 dest[len] = 0;
310 return res;
311}
312EXPORT_SYMBOL(strlcat);
313#endif
314
315#ifndef __HAVE_ARCH_STRCMP
316
317
318
319
320
321#undef strcmp
322int strcmp(const char *cs, const char *ct)
323{
324 unsigned char c1, c2;
325
326 while (1) {
327 c1 = *cs++;
328 c2 = *ct++;
329 if (c1 != c2)
330 return c1 < c2 ? -1 : 1;
331 if (!c1)
332 break;
333 }
334 return 0;
335}
336EXPORT_SYMBOL(strcmp);
337#endif
338
339#ifndef __HAVE_ARCH_STRNCMP
340
341
342
343
344
345
346int strncmp(const char *cs, const char *ct, size_t count)
347{
348 unsigned char c1, c2;
349
350 while (count) {
351 c1 = *cs++;
352 c2 = *ct++;
353 if (c1 != c2)
354 return c1 < c2 ? -1 : 1;
355 if (!c1)
356 break;
357 count--;
358 }
359 return 0;
360}
361EXPORT_SYMBOL(strncmp);
362#endif
363
364#ifndef __HAVE_ARCH_STRCHR
365
366
367
368
369
370char *strchr(const char *s, int c)
371{
372 for (; *s != (char)c; ++s)
373 if (*s == '\0')
374 return NULL;
375 return (char *)s;
376}
377EXPORT_SYMBOL(strchr);
378#endif
379
380#ifndef __HAVE_ARCH_STRCHRNUL
381
382
383
384
385
386
387
388
389char *strchrnul(const char *s, int c)
390{
391 while (*s && *s != (char)c)
392 s++;
393 return (char *)s;
394}
395EXPORT_SYMBOL(strchrnul);
396#endif
397
398#ifndef __HAVE_ARCH_STRRCHR
399
400
401
402
403
404char *strrchr(const char *s, int c)
405{
406 const char *last = NULL;
407 do {
408 if (*s == (char)c)
409 last = s;
410 } while (*s++);
411 return (char *)last;
412}
413EXPORT_SYMBOL(strrchr);
414#endif
415
416#ifndef __HAVE_ARCH_STRNCHR
417
418
419
420
421
422
423char *strnchr(const char *s, size_t count, int c)
424{
425 for (; count-- && *s != '\0'; ++s)
426 if (*s == (char)c)
427 return (char *)s;
428 return NULL;
429}
430EXPORT_SYMBOL(strnchr);
431#endif
432
433
434
435
436
437
438
439char *skip_spaces(const char *str)
440{
441 while (isspace(*str))
442 ++str;
443 return (char *)str;
444}
445EXPORT_SYMBOL(skip_spaces);
446
447
448
449
450
451
452
453
454
455char *strim(char *s)
456{
457 size_t size;
458 char *end;
459
460 size = strlen(s);
461 if (!size)
462 return s;
463
464 end = s + size - 1;
465 while (end >= s && isspace(*end))
466 end--;
467 *(end + 1) = '\0';
468
469 return skip_spaces(s);
470}
471EXPORT_SYMBOL(strim);
472
473#ifndef __HAVE_ARCH_STRLEN
474
475
476
477
478size_t strlen(const char *s)
479{
480 const char *sc;
481
482 for (sc = s; *sc != '\0'; ++sc)
483 ;
484 return sc - s;
485}
486EXPORT_SYMBOL(strlen);
487#endif
488
489#ifndef __HAVE_ARCH_STRNLEN
490
491
492
493
494
495size_t strnlen(const char *s, size_t count)
496{
497 const char *sc;
498
499 for (sc = s; count-- && *sc != '\0'; ++sc)
500 ;
501 return sc - s;
502}
503EXPORT_SYMBOL(strnlen);
504#endif
505
506#ifndef __HAVE_ARCH_STRSPN
507
508
509
510
511
512size_t strspn(const char *s, const char *accept)
513{
514 const char *p;
515 const char *a;
516 size_t count = 0;
517
518 for (p = s; *p != '\0'; ++p) {
519 for (a = accept; *a != '\0'; ++a) {
520 if (*p == *a)
521 break;
522 }
523 if (*a == '\0')
524 return count;
525 ++count;
526 }
527 return count;
528}
529
530EXPORT_SYMBOL(strspn);
531#endif
532
533#ifndef __HAVE_ARCH_STRCSPN
534
535
536
537
538
539size_t strcspn(const char *s, const char *reject)
540{
541 const char *p;
542 const char *r;
543 size_t count = 0;
544
545 for (p = s; *p != '\0'; ++p) {
546 for (r = reject; *r != '\0'; ++r) {
547 if (*p == *r)
548 return count;
549 }
550 ++count;
551 }
552 return count;
553}
554EXPORT_SYMBOL(strcspn);
555#endif
556
557#ifndef __HAVE_ARCH_STRPBRK
558
559
560
561
562
563char *strpbrk(const char *cs, const char *ct)
564{
565 const char *sc1, *sc2;
566
567 for (sc1 = cs; *sc1 != '\0'; ++sc1) {
568 for (sc2 = ct; *sc2 != '\0'; ++sc2) {
569 if (*sc1 == *sc2)
570 return (char *)sc1;
571 }
572 }
573 return NULL;
574}
575EXPORT_SYMBOL(strpbrk);
576#endif
577
578#ifndef __HAVE_ARCH_STRSEP
579
580
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582
583
584
585
586
587
588
589
590char *strsep(char **s, const char *ct)
591{
592 char *sbegin = *s;
593 char *end;
594
595 if (sbegin == NULL)
596 return NULL;
597
598 end = strpbrk(sbegin, ct);
599 if (end)
600 *end++ = '\0';
601 *s = end;
602 return sbegin;
603}
604EXPORT_SYMBOL(strsep);
605#endif
606
607
608
609
610
611
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613
614
615
616
617bool sysfs_streq(const char *s1, const char *s2)
618{
619 while (*s1 && *s1 == *s2) {
620 s1++;
621 s2++;
622 }
623
624 if (*s1 == *s2)
625 return true;
626 if (!*s1 && *s2 == '\n' && !s2[1])
627 return true;
628 if (*s1 == '\n' && !s1[1] && !*s2)
629 return true;
630 return false;
631}
632EXPORT_SYMBOL(sysfs_streq);
633
634
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638
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641
642
643int match_string(const char * const *array, size_t n, const char *string)
644{
645 int index;
646 const char *item;
647
648 for (index = 0; index < n; index++) {
649 item = array[index];
650 if (!item)
651 break;
652 if (!strcmp(item, string))
653 return index;
654 }
655
656 return -EINVAL;
657}
658EXPORT_SYMBOL(match_string);
659
660
661
662
663
664
665
666
667
668
669int __sysfs_match_string(const char * const *array, size_t n, const char *str)
670{
671 const char *item;
672 int index;
673
674 for (index = 0; index < n; index++) {
675 item = array[index];
676 if (!item)
677 break;
678 if (sysfs_streq(item, str))
679 return index;
680 }
681
682 return -EINVAL;
683}
684EXPORT_SYMBOL(__sysfs_match_string);
685
686#ifndef __HAVE_ARCH_MEMSET
687
688
689
690
691
692
693
694
695void *memset(void *s, int c, size_t count)
696{
697 char *xs = s;
698
699 while (count--)
700 *xs++ = c;
701 return s;
702}
703EXPORT_SYMBOL(memset);
704#endif
705
706
707
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709
710
711
712
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715
716
717
718
719
720void memzero_explicit(void *s, size_t count)
721{
722 memset(s, 0, count);
723 barrier_data(s);
724}
725EXPORT_SYMBOL(memzero_explicit);
726
727#ifndef __HAVE_ARCH_MEMSET16
728
729
730
731
732
733
734
735
736
737
738void *memset16(uint16_t *s, uint16_t v, size_t count)
739{
740 uint16_t *xs = s;
741
742 while (count--)
743 *xs++ = v;
744 return s;
745}
746EXPORT_SYMBOL(memset16);
747#endif
748
749#ifndef __HAVE_ARCH_MEMSET32
750
751
752
753
754
755
756
757
758
759
760void *memset32(uint32_t *s, uint32_t v, size_t count)
761{
762 uint32_t *xs = s;
763
764 while (count--)
765 *xs++ = v;
766 return s;
767}
768EXPORT_SYMBOL(memset32);
769#endif
770
771#ifndef __HAVE_ARCH_MEMSET64
772
773
774
775
776
777
778
779
780
781
782void *memset64(uint64_t *s, uint64_t v, size_t count)
783{
784 uint64_t *xs = s;
785
786 while (count--)
787 *xs++ = v;
788 return s;
789}
790EXPORT_SYMBOL(memset64);
791#endif
792
793#ifndef __HAVE_ARCH_MEMCPY
794
795
796
797
798
799
800
801
802
803void *memcpy(void *dest, const void *src, size_t count)
804{
805 char *tmp = dest;
806 const char *s = src;
807
808 while (count--)
809 *tmp++ = *s++;
810 return dest;
811}
812EXPORT_SYMBOL(memcpy);
813#endif
814
815#ifndef __HAVE_ARCH_MEMMOVE
816
817
818
819
820
821
822
823
824void *memmove(void *dest, const void *src, size_t count)
825{
826 char *tmp;
827 const char *s;
828
829 if (dest <= src) {
830 tmp = dest;
831 s = src;
832 while (count--)
833 *tmp++ = *s++;
834 } else {
835 tmp = dest;
836 tmp += count;
837 s = src;
838 s += count;
839 while (count--)
840 *--tmp = *--s;
841 }
842 return dest;
843}
844EXPORT_SYMBOL(memmove);
845#endif
846
847#ifndef __HAVE_ARCH_MEMCMP
848
849
850
851
852
853
854#undef memcmp
855__visible int memcmp(const void *cs, const void *ct, size_t count)
856{
857 const unsigned char *su1, *su2;
858 int res = 0;
859
860 for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
861 if ((res = *su1 - *su2) != 0)
862 break;
863 return res;
864}
865EXPORT_SYMBOL(memcmp);
866#endif
867
868#ifndef __HAVE_ARCH_MEMSCAN
869
870
871
872
873
874
875
876
877
878void *memscan(void *addr, int c, size_t size)
879{
880 unsigned char *p = addr;
881
882 while (size) {
883 if (*p == c)
884 return (void *)p;
885 p++;
886 size--;
887 }
888 return (void *)p;
889}
890EXPORT_SYMBOL(memscan);
891#endif
892
893#ifndef __HAVE_ARCH_STRSTR
894
895
896
897
898
899char *strstr(const char *s1, const char *s2)
900{
901 size_t l1, l2;
902
903 l2 = strlen(s2);
904 if (!l2)
905 return (char *)s1;
906 l1 = strlen(s1);
907 while (l1 >= l2) {
908 l1--;
909 if (!memcmp(s1, s2, l2))
910 return (char *)s1;
911 s1++;
912 }
913 return NULL;
914}
915EXPORT_SYMBOL(strstr);
916#endif
917
918#ifndef __HAVE_ARCH_STRNSTR
919
920
921
922
923
924
925char *strnstr(const char *s1, const char *s2, size_t len)
926{
927 size_t l2;
928
929 l2 = strlen(s2);
930 if (!l2)
931 return (char *)s1;
932 while (len >= l2) {
933 len--;
934 if (!memcmp(s1, s2, l2))
935 return (char *)s1;
936 s1++;
937 }
938 return NULL;
939}
940EXPORT_SYMBOL(strnstr);
941#endif
942
943#ifndef __HAVE_ARCH_MEMCHR
944
945
946
947
948
949
950
951
952
953void *memchr(const void *s, int c, size_t n)
954{
955 const unsigned char *p = s;
956 while (n-- != 0) {
957 if ((unsigned char)c == *p++) {
958 return (void *)(p - 1);
959 }
960 }
961 return NULL;
962}
963EXPORT_SYMBOL(memchr);
964#endif
965
966static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes)
967{
968 while (bytes) {
969 if (*start != value)
970 return (void *)start;
971 start++;
972 bytes--;
973 }
974 return NULL;
975}
976
977
978
979
980
981
982
983
984
985
986void *memchr_inv(const void *start, int c, size_t bytes)
987{
988 u8 value = c;
989 u64 value64;
990 unsigned int words, prefix;
991
992 if (bytes <= 16)
993 return check_bytes8(start, value, bytes);
994
995 value64 = value;
996#if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64
997 value64 *= 0x0101010101010101ULL;
998#elif defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER)
999 value64 *= 0x01010101;
1000 value64 |= value64 << 32;
1001#else
1002 value64 |= value64 << 8;
1003 value64 |= value64 << 16;
1004 value64 |= value64 << 32;
1005#endif
1006
1007 prefix = (unsigned long)start % 8;
1008 if (prefix) {
1009 u8 *r;
1010
1011 prefix = 8 - prefix;
1012 r = check_bytes8(start, value, prefix);
1013 if (r)
1014 return r;
1015 start += prefix;
1016 bytes -= prefix;
1017 }
1018
1019 words = bytes / 8;
1020
1021 while (words) {
1022 if (*(u64 *)start != value64)
1023 return check_bytes8(start, value, 8);
1024 start += 8;
1025 words--;
1026 }
1027
1028 return check_bytes8(start, value, bytes % 8);
1029}
1030EXPORT_SYMBOL(memchr_inv);
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040char *strreplace(char *s, char old, char new)
1041{
1042 for (; *s; ++s)
1043 if (*s == old)
1044 *s = new;
1045 return s;
1046}
1047EXPORT_SYMBOL(strreplace);
1048
1049void fortify_panic(const char *name)
1050{
1051 pr_emerg("detected buffer overflow in %s\n", name);
1052 BUG();
1053}
1054EXPORT_SYMBOL(fortify_panic);
1055