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git.ipfire.org Git - people/ms/u-boot.git/blob - lib/string.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
8 * stupid library routines.. The optimized versions should generally be found
9 * as inline code in <asm-xx/string.h>
11 * These are buggy as well..
13 * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>
14 * - Added strsep() which will replace strtok() soon (because strsep() is
15 * reentrant and should be faster). Use only strsep() in new code, please.
18 #include <linux/types.h>
19 #include <linux/string.h>
20 #include <linux/ctype.h>
25 * strncasecmp - Case insensitive, length-limited string comparison
27 * @s2: The other string
28 * @len: the maximum number of characters to compare
30 int strncasecmp(const char *s1
, const char *s2
, size_t len
)
32 /* Yes, Virginia, it had better be unsigned */
52 return (int)c1
- (int)c2
;
56 * strcasecmp - Case insensitive string comparison
58 * @s2: The other string
60 int strcasecmp(const char *s1
, const char *s2
)
62 return strncasecmp(s1
, s2
, -1U);
67 #ifndef __HAVE_ARCH_STRCPY
69 * strcpy - Copy a %NUL terminated string
70 * @dest: Where to copy the string to
71 * @src: Where to copy the string from
73 char * strcpy(char * dest
,const char *src
)
77 while ((*dest
++ = *src
++) != '\0')
83 #ifndef __HAVE_ARCH_STRNCPY
85 * strncpy - Copy a length-limited, %NUL-terminated string
86 * @dest: Where to copy the string to
87 * @src: Where to copy the string from
88 * @count: The maximum number of bytes to copy
90 * Note that unlike userspace strncpy, this does not %NUL-pad the buffer.
91 * However, the result is not %NUL-terminated if the source exceeds
94 char * strncpy(char * dest
,const char *src
,size_t count
)
98 while (count
-- && (*dest
++ = *src
++) != '\0')
105 #ifndef __HAVE_ARCH_STRCAT
107 * strcat - Append one %NUL-terminated string to another
108 * @dest: The string to be appended to
109 * @src: The string to append to it
111 char * strcat(char * dest
, const char * src
)
117 while ((*dest
++ = *src
++) != '\0')
124 #ifndef __HAVE_ARCH_STRNCAT
126 * strncat - Append a length-limited, %NUL-terminated string to another
127 * @dest: The string to be appended to
128 * @src: The string to append to it
129 * @count: The maximum numbers of bytes to copy
131 * Note that in contrast to strncpy, strncat ensures the result is
134 char * strncat(char *dest
, const char *src
, size_t count
)
141 while ((*dest
++ = *src
++)) {
153 #ifndef __HAVE_ARCH_STRCMP
155 * strcmp - Compare two strings
157 * @ct: Another string
159 int strcmp(const char * cs
,const char * ct
)
161 register signed char __res
;
164 if ((__res
= *cs
- *ct
++) != 0 || !*cs
++)
172 #ifndef __HAVE_ARCH_STRNCMP
174 * strncmp - Compare two length-limited strings
176 * @ct: Another string
177 * @count: The maximum number of bytes to compare
179 int strncmp(const char * cs
,const char * ct
,size_t count
)
181 register signed char __res
= 0;
184 if ((__res
= *cs
- *ct
++) != 0 || !*cs
++)
193 #ifndef __HAVE_ARCH_STRCHR
195 * strchr - Find the first occurrence of a character in a string
196 * @s: The string to be searched
197 * @c: The character to search for
199 char * strchr(const char * s
, int c
)
201 for(; *s
!= (char) c
; ++s
)
208 #ifndef __HAVE_ARCH_STRRCHR
210 * strrchr - Find the last occurrence of a character in a string
211 * @s: The string to be searched
212 * @c: The character to search for
214 char * strrchr(const char * s
, int c
)
216 const char *p
= s
+ strlen(s
);
225 #ifndef __HAVE_ARCH_STRLEN
227 * strlen - Find the length of a string
228 * @s: The string to be sized
230 size_t strlen(const char * s
)
234 for (sc
= s
; *sc
!= '\0'; ++sc
)
240 #ifndef __HAVE_ARCH_STRNLEN
242 * strnlen - Find the length of a length-limited string
243 * @s: The string to be sized
244 * @count: The maximum number of bytes to search
246 size_t strnlen(const char * s
, size_t count
)
250 for (sc
= s
; count
-- && *sc
!= '\0'; ++sc
)
256 #ifndef __HAVE_ARCH_STRDUP
257 char * strdup(const char *s
)
262 ((new = malloc (strlen(s
) + 1)) == NULL
) ) {
271 #ifndef __HAVE_ARCH_STRSPN
273 * strspn - Calculate the length of the initial substring of @s which only
274 * contain letters in @accept
275 * @s: The string to be searched
276 * @accept: The string to search for
278 size_t strspn(const char *s
, const char *accept
)
284 for (p
= s
; *p
!= '\0'; ++p
) {
285 for (a
= accept
; *a
!= '\0'; ++a
) {
298 #ifndef __HAVE_ARCH_STRPBRK
300 * strpbrk - Find the first occurrence of a set of characters
301 * @cs: The string to be searched
302 * @ct: The characters to search for
304 char * strpbrk(const char * cs
,const char * ct
)
306 const char *sc1
,*sc2
;
308 for( sc1
= cs
; *sc1
!= '\0'; ++sc1
) {
309 for( sc2
= ct
; *sc2
!= '\0'; ++sc2
) {
318 #ifndef __HAVE_ARCH_STRTOK
320 * strtok - Split a string into tokens
321 * @s: The string to be searched
322 * @ct: The characters to search for
324 * WARNING: strtok is deprecated, use strsep instead.
326 char * strtok(char * s
,const char * ct
)
330 sbegin
= s
? s
: ___strtok
;
334 sbegin
+= strspn(sbegin
,ct
);
335 if (*sbegin
== '\0') {
339 send
= strpbrk( sbegin
, ct
);
340 if (send
&& *send
!= '\0')
347 #ifndef __HAVE_ARCH_STRSEP
349 * strsep - Split a string into tokens
350 * @s: The string to be searched
351 * @ct: The characters to search for
353 * strsep() updates @s to point after the token, ready for the next call.
355 * It returns empty tokens, too, behaving exactly like the libc function
356 * of that name. In fact, it was stolen from glibc2 and de-fancy-fied.
357 * Same semantics, slimmer shape. ;)
359 char * strsep(char **s
, const char *ct
)
361 char *sbegin
= *s
, *end
;
366 end
= strpbrk(sbegin
, ct
);
375 #ifndef __HAVE_ARCH_STRSWAB
377 * strswab - swap adjacent even and odd bytes in %NUL-terminated string
378 * s: address of the string
380 * returns the address of the swapped string or NULL on error. If
381 * string length is odd, last byte is untouched.
383 char *strswab(const char *s
)
387 if ((NULL
== s
) || ('\0' == *s
)) {
391 for (p
=(char *)s
, q
=p
+1; (*p
!= '\0') && (*q
!= '\0'); p
+=2, q
+=2) {
403 #ifndef __HAVE_ARCH_MEMSET
405 * memset - Fill a region of memory with the given value
406 * @s: Pointer to the start of the area.
407 * @c: The byte to fill the area with
408 * @count: The size of the area.
410 * Do not use memset() to access IO space, use memset_io() instead.
412 void * memset(void * s
,int c
,size_t count
)
414 unsigned long *sl
= (unsigned long *) s
;
415 unsigned long cl
= 0;
419 /* do it one word at a time (32 bits or 64 bits) while possible */
420 if ( ((ulong
)s
& (sizeof(*sl
) - 1)) == 0) {
421 for (i
= 0; i
< sizeof(*sl
); i
++) {
425 while (count
>= sizeof(*sl
)) {
427 count
-= sizeof(*sl
);
430 /* fill 8 bits at a time */
439 #ifndef __HAVE_ARCH_BCOPY
441 * bcopy - Copy one area of memory to another
442 * @src: Where to copy from
443 * @dest: Where to copy to
444 * @count: The size of the area.
446 * Note that this is the same as memcpy(), with the arguments reversed.
447 * memcpy() is the standard, bcopy() is a legacy BSD function.
449 * You should not use this function to access IO space, use memcpy_toio()
450 * or memcpy_fromio() instead.
452 char * bcopy(const char * src
, char * dest
, int count
)
463 #ifndef __HAVE_ARCH_MEMCPY
465 * memcpy - Copy one area of memory to another
466 * @dest: Where to copy to
467 * @src: Where to copy from
468 * @count: The size of the area.
470 * You should not use this function to access IO space, use memcpy_toio()
471 * or memcpy_fromio() instead.
473 void * memcpy(void *dest
, const void *src
, size_t count
)
475 unsigned long *dl
= (unsigned long *)dest
, *sl
= (unsigned long *)src
;
481 /* while all data is aligned (common case), copy a word at a time */
482 if ( (((ulong
)dest
| (ulong
)src
) & (sizeof(*dl
) - 1)) == 0) {
483 while (count
>= sizeof(*dl
)) {
485 count
-= sizeof(*dl
);
488 /* copy the reset one byte at a time */
498 #ifndef __HAVE_ARCH_MEMMOVE
500 * memmove - Copy one area of memory to another
501 * @dest: Where to copy to
502 * @src: Where to copy from
503 * @count: The size of the area.
505 * Unlike memcpy(), memmove() copes with overlapping areas.
507 void * memmove(void * dest
,const void *src
,size_t count
)
521 tmp
= (char *) dest
+ count
;
522 s
= (char *) src
+ count
;
531 #ifndef __HAVE_ARCH_MEMCMP
533 * memcmp - Compare two areas of memory
534 * @cs: One area of memory
535 * @ct: Another area of memory
536 * @count: The size of the area.
538 int memcmp(const void * cs
,const void * ct
,size_t count
)
540 const unsigned char *su1
, *su2
;
543 for( su1
= cs
, su2
= ct
; 0 < count
; ++su1
, ++su2
, count
--)
544 if ((res
= *su1
- *su2
) != 0)
550 #ifndef __HAVE_ARCH_MEMSCAN
552 * memscan - Find a character in an area of memory.
553 * @addr: The memory area
554 * @c: The byte to search for
555 * @size: The size of the area.
557 * returns the address of the first occurrence of @c, or 1 byte past
558 * the area if @c is not found
560 void * memscan(void * addr
, int c
, size_t size
)
562 unsigned char * p
= (unsigned char *) addr
;
574 #ifndef __HAVE_ARCH_STRSTR
576 * strstr - Find the first substring in a %NUL terminated string
577 * @s1: The string to be searched
578 * @s2: The string to search for
580 char * strstr(const char * s1
,const char * s2
)
590 if (!memcmp(s1
,s2
,l2
))
598 #ifndef __HAVE_ARCH_MEMCHR
600 * memchr - Find a character in an area of memory.
601 * @s: The memory area
602 * @c: The byte to search for
603 * @n: The size of the area.
605 * returns the address of the first occurrence of @c, or %NULL
608 void *memchr(const void *s
, int c
, size_t n
)
610 const unsigned char *p
= s
;
612 if ((unsigned char)c
== *p
++) {
613 return (void *)(p
-1);
620 #ifndef __HAVE_ARCH_MEMCHR_INV
621 static void *check_bytes8(const u8
*start
, u8 value
, unsigned int bytes
)
625 return (void *)start
;
632 * memchr_inv - Find an unmatching character in an area of memory.
633 * @start: The memory area
634 * @c: Find a character other than c
635 * @bytes: The size of the area.
637 * returns the address of the first character other than @c, or %NULL
638 * if the whole buffer contains just @c.
640 void *memchr_inv(const void *start
, int c
, size_t bytes
)
644 unsigned int words
, prefix
;
647 return check_bytes8(start
, value
, bytes
);
650 value64
|= value64
<< 8;
651 value64
|= value64
<< 16;
652 value64
|= value64
<< 32;
654 prefix
= (unsigned long)start
% 8;
659 r
= check_bytes8(start
, value
, prefix
);
669 if (*(u64
*)start
!= value64
)
670 return check_bytes8(start
, value
, 8);
675 return check_bytes8(start
, value
, bytes
% 8);