[J-u-boot.git] / lib / string.c

/*
 *  linux/lib/string.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/*
 * stupid library routines.. The optimized versions should generally be found
 * as inline code in <asm-xx/string.h>
 *
 * These are buggy as well..
 *
 * * Fri Jun 25 1999, Ingo Oeser <[email protected]>
 * -  Added strsep() which will replace strtok() soon (because strsep() is
 *    reentrant and should be faster). Use only strsep() in new code, please.
 */

#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <malloc.h>


/**
 * strncasecmp - Case insensitive, length-limited string comparison
 * @s1: One string
 * @s2: The other string
 * @len: the maximum number of characters to compare
 */
int strncasecmp(const char *s1, const char *s2, size_t len)
{
	/* Yes, Virginia, it had better be unsigned */
	unsigned char c1, c2;

	c1 = 0;	c2 = 0;
	if (len) {
		do {
			c1 = *s1; c2 = *s2;
			s1++; s2++;
			if (!c1)
				break;
			if (!c2)
				break;
			if (c1 == c2)
				continue;
			c1 = tolower(c1);
			c2 = tolower(c2);
			if (c1 != c2)
				break;
		} while (--len);
	}
	return (int)c1 - (int)c2;
}

/**
 * strcasecmp - Case insensitive string comparison
 * @s1: One string
 * @s2: The other string
 */
int strcasecmp(const char *s1, const char *s2)
{
	return strncasecmp(s1, s2, -1U);
}

char * ___strtok;

#ifndef __HAVE_ARCH_STRCPY
/**
 * strcpy - Copy a %NUL terminated string
 * @dest: Where to copy the string to
 * @src: Where to copy the string from
 */
char * strcpy(char * dest,const char *src)
{
	char *tmp = dest;

	while ((*dest++ = *src++) != '\0')
		/* nothing */;
	return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRNCPY
/**
 * strncpy - Copy a length-limited, %NUL-terminated string
 * @dest: Where to copy the string to
 * @src: Where to copy the string from
 * @count: The maximum number of bytes to copy
 *
 * Note that unlike userspace strncpy, this does not %NUL-pad the buffer.
 * However, the result is not %NUL-terminated if the source exceeds
 * @count bytes.
 */
char * strncpy(char * dest,const char *src,size_t count)
{
	char *tmp = dest;

	while (count-- && (*dest++ = *src++) != '\0')
		/* nothing */;

	return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRCAT
/**
 * strcat - Append one %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 */
char * strcat(char * dest, const char * src)
{
	char *tmp = dest;

	while (*dest)
		dest++;
	while ((*dest++ = *src++) != '\0')
		;

	return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRNCAT
/**
 * strncat - Append a length-limited, %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 * @count: The maximum numbers of bytes to copy
 *
 * Note that in contrast to strncpy, strncat ensures the result is
 * terminated.
 */
char * strncat(char *dest, const char *src, size_t count)
{
	char *tmp = dest;

	if (count) {
		while (*dest)
			dest++;
		while ((*dest++ = *src++)) {
			if (--count == 0) {
				*dest = '\0';
				break;
			}
		}
	}

	return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRCMP
/**
 * strcmp - Compare two strings
 * @cs: One string
 * @ct: Another string
 */
int strcmp(const char * cs,const char * ct)
{
	register signed char __res;

	while (1) {
		if ((__res = *cs - *ct++) != 0 || !*cs++)
			break;
	}

	return __res;
}
#endif

#ifndef __HAVE_ARCH_STRNCMP
/**
 * strncmp - Compare two length-limited strings
 * @cs: One string
 * @ct: Another string
 * @count: The maximum number of bytes to compare
 */
int strncmp(const char * cs,const char * ct,size_t count)
{
	register signed char __res = 0;

	while (count) {
		if ((__res = *cs - *ct++) != 0 || !*cs++)
			break;
		count--;
	}

	return __res;
}
#endif

#ifndef __HAVE_ARCH_STRCHR
/**
 * strchr - Find the first occurrence of a character in a string
 * @s: The string to be searched
 * @c: The character to search for
 */
char * strchr(const char * s, int c)
{
	for(; *s != (char) c; ++s)
		if (*s == '\0')
			return NULL;
	return (char *) s;
}
#endif

#ifndef __HAVE_ARCH_STRRCHR
/**
 * strrchr - Find the last occurrence of a character in a string
 * @s: The string to be searched
 * @c: The character to search for
 */
char * strrchr(const char * s, int c)
{
       const char *p = s + strlen(s);
       do {
	   if (*p == (char)c)
	       return (char *)p;
       } while (--p >= s);
       return NULL;
}
#endif

#ifndef __HAVE_ARCH_STRLEN
/**
 * strlen - Find the length of a string
 * @s: The string to be sized
 */
size_t strlen(const char * s)
{
	const char *sc;

	for (sc = s; *sc != '\0'; ++sc)
		/* nothing */;
	return sc - s;
}
#endif

#ifndef __HAVE_ARCH_STRNLEN
/**
 * strnlen - Find the length of a length-limited string
 * @s: The string to be sized
 * @count: The maximum number of bytes to search
 */
size_t strnlen(const char * s, size_t count)
{
	const char *sc;

	for (sc = s; count-- && *sc != '\0'; ++sc)
		/* nothing */;
	return sc - s;
}
#endif

#ifndef __HAVE_ARCH_STRDUP
char * strdup(const char *s)
{
	char *new;

	if ((s == NULL)	||
	    ((new = malloc (strlen(s) + 1)) == NULL) ) {
		return NULL;
	}

	strcpy (new, s);
	return new;
}
#endif

#ifndef __HAVE_ARCH_STRSPN
/**
 * strspn - Calculate the length of the initial substring of @s which only
 *	contain letters in @accept
 * @s: The string to be searched
 * @accept: The string to search for
 */
size_t strspn(const char *s, const char *accept)
{
	const char *p;
	const char *a;
	size_t count = 0;

	for (p = s; *p != '\0'; ++p) {
		for (a = accept; *a != '\0'; ++a) {
			if (*p == *a)
				break;
		}
		if (*a == '\0')
			return count;
		++count;
	}

	return count;
}
#endif

#ifndef __HAVE_ARCH_STRPBRK
/**
 * strpbrk - Find the first occurrence of a set of characters
 * @cs: The string to be searched
 * @ct: The characters to search for
 */
char * strpbrk(const char * cs,const char * ct)
{
	const char *sc1,*sc2;

	for( sc1 = cs; *sc1 != '\0'; ++sc1) {
		for( sc2 = ct; *sc2 != '\0'; ++sc2) {
			if (*sc1 == *sc2)
				return (char *) sc1;
		}
	}
	return NULL;
}
#endif

#ifndef __HAVE_ARCH_STRTOK
/**
 * strtok - Split a string into tokens
 * @s: The string to be searched
 * @ct: The characters to search for
 *
 * WARNING: strtok is deprecated, use strsep instead.
 */
char * strtok(char * s,const char * ct)
{
	char *sbegin, *send;

	sbegin  = s ? s : ___strtok;
	if (!sbegin) {
		return NULL;
	}
	sbegin += strspn(sbegin,ct);
	if (*sbegin == '\0') {
		___strtok = NULL;
		return( NULL );
	}
	send = strpbrk( sbegin, ct);
	if (send && *send != '\0')
		*send++ = '\0';
	___strtok = send;
	return (sbegin);
}
#endif

#ifndef __HAVE_ARCH_STRSEP
/**
 * strsep - Split a string into tokens
 * @s: The string to be searched
 * @ct: The characters to search for
 *
 * strsep() updates @s to point after the token, ready for the next call.
 *
 * It returns empty tokens, too, behaving exactly like the libc function
 * of that name. In fact, it was stolen from glibc2 and de-fancy-fied.
 * Same semantics, slimmer shape. ;)
 */
char * strsep(char **s, const char *ct)
{
	char *sbegin = *s, *end;

	if (sbegin == NULL)
		return NULL;

	end = strpbrk(sbegin, ct);
	if (end)
		*end++ = '\0';
	*s = end;

	return sbegin;
}
#endif

#ifndef __HAVE_ARCH_STRSWAB
/**
 * strswab - swap adjacent even and odd bytes in %NUL-terminated string
 * s: address of the string
 *
 * returns the address of the swapped string or NULL on error. If
 * string length is odd, last byte is untouched.
 */
char *strswab(const char *s)
{
	char *p, *q;

	if ((NULL == s) || ('\0' == *s)) {
		return (NULL);
	}

	for (p=(char *)s, q=p+1; (*p != '\0') && (*q != '\0'); p+=2, q+=2) {
		char  tmp;

		tmp = *p;
		*p  = *q;
		*q  = tmp;
	}

	return (char *) s;
}
#endif

#ifndef __HAVE_ARCH_MEMSET
/**
 * memset - Fill a region of memory with the given value
 * @s: Pointer to the start of the area.
 * @c: The byte to fill the area with
 * @count: The size of the area.
 *
 * Do not use memset() to access IO space, use memset_io() instead.
 */
void * memset(void * s,int c,size_t count)
{
	unsigned long *sl = (unsigned long *) s;
	unsigned long cl = 0;
	char *s8;
	int i;

	/* do it one word at a time (32 bits or 64 bits) while possible */
	if ( ((ulong)s & (sizeof(*sl) - 1)) == 0) {
		for (i = 0; i < sizeof(*sl); i++) {
			cl <<= 8;
			cl |= c & 0xff;
		}
		while (count >= sizeof(*sl)) {
			*sl++ = cl;
			count -= sizeof(*sl);
		}
	}
	/* fill 8 bits at a time */
	s8 = (char *)sl;
	while (count--)
		*s8++ = c;

	return s;
}
#endif

#ifndef __HAVE_ARCH_BCOPY
/**
 * bcopy - Copy one area of memory to another
 * @src: Where to copy from
 * @dest: Where to copy to
 * @count: The size of the area.
 *
 * Note that this is the same as memcpy(), with the arguments reversed.
 * memcpy() is the standard, bcopy() is a legacy BSD function.
 *
 * You should not use this function to access IO space, use memcpy_toio()
 * or memcpy_fromio() instead.
 */
char * bcopy(const char * src, char * dest, int count)
{
	char *tmp = dest;

	while (count--)
		*tmp++ = *src++;

	return dest;
}
#endif

#ifndef __HAVE_ARCH_MEMCPY
/**
 * memcpy - Copy one area of memory to another
 * @dest: Where to copy to
 * @src: Where to copy from
 * @count: The size of the area.
 *
 * You should not use this function to access IO space, use memcpy_toio()
 * or memcpy_fromio() instead.
 */
void * memcpy(void *dest, const void *src, size_t count)
{
	unsigned long *dl = (unsigned long *)dest, *sl = (unsigned long *)src;
	char *d8, *s8;

	if (src == dest)
		return dest;

	/* while all data is aligned (common case), copy a word at a time */
	if ( (((ulong)dest | (ulong)src) & (sizeof(*dl) - 1)) == 0) {
		while (count >= sizeof(*dl)) {
			*dl++ = *sl++;
			count -= sizeof(*dl);
		}
	}
	/* copy the reset one byte at a time */
	d8 = (char *)dl;
	s8 = (char *)sl;
	while (count--)
		*d8++ = *s8++;

	return dest;
}
#endif

#ifndef __HAVE_ARCH_MEMMOVE
/**
 * memmove - Copy one area of memory to another
 * @dest: Where to copy to
 * @src: Where to copy from
 * @count: The size of the area.
 *
 * Unlike memcpy(), memmove() copes with overlapping areas.
 */
void * memmove(void * dest,const void *src,size_t count)
{
	char *tmp, *s;

	if (src == dest)
		return dest;

	if (dest <= src) {
		tmp = (char *) dest;
		s = (char *) src;
		while (count--)
			*tmp++ = *s++;
		}
	else {
		tmp = (char *) dest + count;
		s = (char *) src + count;
		while (count--)
			*--tmp = *--s;
		}

	return dest;
}
#endif

#ifndef __HAVE_ARCH_MEMCMP
/**
 * memcmp - Compare two areas of memory
 * @cs: One area of memory
 * @ct: Another area of memory
 * @count: The size of the area.
 */
int memcmp(const void * cs,const void * ct,size_t count)
{
	const unsigned char *su1, *su2;
	int res = 0;

	for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
		if ((res = *su1 - *su2) != 0)
			break;
	return res;
}
#endif

#ifndef __HAVE_ARCH_MEMSCAN
/**
 * memscan - Find a character in an area of memory.
 * @addr: The memory area
 * @c: The byte to search for
 * @size: The size of the area.
 *
 * returns the address of the first occurrence of @c, or 1 byte past
 * the area if @c is not found
 */
void * memscan(void * addr, int c, size_t size)
{
	unsigned char * p = (unsigned char *) addr;

	while (size) {
		if (*p == c)
			return (void *) p;
		p++;
		size--;
	}
	return (void *) p;
}
#endif

#ifndef __HAVE_ARCH_STRSTR
/**
 * strstr - Find the first substring in a %NUL terminated string
 * @s1: The string to be searched
 * @s2: The string to search for
 */
char * strstr(const char * s1,const char * s2)
{
	int l1, l2;

	l2 = strlen(s2);
	if (!l2)
		return (char *) s1;
	l1 = strlen(s1);
	while (l1 >= l2) {
		l1--;
		if (!memcmp(s1,s2,l2))
			return (char *) s1;
		s1++;
	}
	return NULL;
}
#endif

#ifndef __HAVE_ARCH_MEMCHR
/**
 * memchr - Find a character in an area of memory.
 * @s: The memory area
 * @c: The byte to search for
 * @n: The size of the area.
 *
 * returns the address of the first occurrence of @c, or %NULL
 * if @c is not found
 */
void *memchr(const void *s, int c, size_t n)
{
	const unsigned char *p = s;
	while (n-- != 0) {
		if ((unsigned char)c == *p++) {
			return (void *)(p-1);
		}
	}
	return NULL;
}

#endif
#ifndef __HAVE_ARCH_MEMCHR_INV
static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes)
{
	while (bytes) {
		if (*start != value)
			return (void *)start;
		start++;
		bytes--;
	}
	return NULL;
}
/**
 * memchr_inv - Find an unmatching character in an area of memory.
 * @start: The memory area
 * @c: Find a character other than c
 * @bytes: The size of the area.
 *
 * returns the address of the first character other than @c, or %NULL
 * if the whole buffer contains just @c.
 */
void *memchr_inv(const void *start, int c, size_t bytes)
{
	u8 value = c;
	u64 value64;
	unsigned int words, prefix;

	if (bytes <= 16)
		return check_bytes8(start, value, bytes);

	value64 = value;
	value64 |= value64 << 8;
	value64 |= value64 << 16;
	value64 |= value64 << 32;

	prefix = (unsigned long)start % 8;
	if (prefix) {
		u8 *r;

		prefix = 8 - prefix;
		r = check_bytes8(start, value, prefix);
		if (r)
			return r;
		start += prefix;
		bytes -= prefix;
	}

	words = bytes / 8;

	while (words) {
		if (*(u64 *)start != value64)
			return check_bytes8(start, value, 8);
		start += 8;
		words--;
	}

	return check_bytes8(start, value, bytes % 8);
}
#endif
Commit	Line	Data
c609719b WD	1	/*
	2	* linux/lib/string.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	*/
	6
	7	/*
	8	* stupid library routines.. The optimized versions should generally be found
	9	* as inline code in <asm-xx/string.h>
	10	*
	11	* These are buggy as well..
	12	*
	13	* * Fri Jun 25 1999, Ingo Oeser <[email protected]>
	14	* - Added strsep() which will replace strtok() soon (because strsep() is
	15	* reentrant and should be faster). Use only strsep() in new code, please.
	16	*/
	17
	18	#include <linux/types.h>
	19	#include <linux/string.h>
	20	#include <linux/ctype.h>
	21	#include <malloc.h>
	22
c609719b	23
c609719b	24	/**
b1f17bf5	25	* strncasecmp - Case insensitive, length-limited string comparison
c609719b WD	26	* @s1: One string
	27	* @s2: The other string
	28	* @len: the maximum number of characters to compare
	29	*/
b1f17bf5	30	int strncasecmp(const char s1, const char s2, size_t len)
c609719b WD	31	{
	32	/* Yes, Virginia, it had better be unsigned */
	33	unsigned char c1, c2;
	34
	35	c1 = 0; c2 = 0;
	36	if (len) {
	37	do {
	38	c1 = s1; c2 = s2;
	39	s1++; s2++;
	40	if (!c1)
	41	break;
	42	if (!c2)
	43	break;
	44	if (c1 == c2)
	45	continue;
	46	c1 = tolower(c1);
	47	c2 = tolower(c2);
	48	if (c1 != c2)
	49	break;
	50	} while (--len);
	51	}
	52	return (int)c1 - (int)c2;
	53	}
b1f17bf5 SG	54
	55	/**
	56	* strcasecmp - Case insensitive string comparison
	57	* @s1: One string
	58	* @s2: The other string
	59	*/
	60	int strcasecmp(const char s1, const char s2)
	61	{
	62	return strncasecmp(s1, s2, -1U);
	63	}
c609719b WD	64
	65	char * ___strtok;
	66
	67	#ifndef __HAVE_ARCH_STRCPY
	68	/**
	69	* strcpy - Copy a %NUL terminated string
	70	* @dest: Where to copy the string to
	71	* @src: Where to copy the string from
	72	*/
	73	char * strcpy(char * dest,const char *src)
	74	{
	75	char *tmp = dest;
	76
	77	while ((dest++ = src++) != '\0')
	78	/* nothing */;
	79	return tmp;
	80	}
	81	#endif
	82
	83	#ifndef __HAVE_ARCH_STRNCPY
	84	/**
	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
	89	*
	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
	92	* @count bytes.
	93	*/
	94	char * strncpy(char * dest,const char *src,size_t count)
	95	{
	96	char *tmp = dest;
	97
	98	while (count-- && (dest++ = src++) != '\0')
	99	/* nothing */;
	100
	101	return tmp;
	102	}
	103	#endif
	104
	105	#ifndef __HAVE_ARCH_STRCAT
	106	/**
	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
	110	*/
	111	char * strcat(char * dest, const char * src)
	112	{
	113	char *tmp = dest;
	114
	115	while (*dest)
	116	dest++;
	117	while ((dest++ = src++) != '\0')
	118	;
	119
	120	return tmp;
	121	}
	122	#endif
	123
	124	#ifndef __HAVE_ARCH_STRNCAT
	125	/**
	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
130	*
131	* Note that in contrast to strncpy, strncat ensures the result is
132	* terminated.
133	*/
134	char * strncat(char dest, const char src, size_t count)
135	{
136	char *tmp = dest;
137
138	if (count) {
139	while (*dest)
140	dest++;
141	while ((dest++ = src++)) {
142	if (--count == 0) {
143	*dest = '\0';
144	break;
145	}
146	}
147	}
148
149	return tmp;
150	}
151	#endif
152
153	#ifndef __HAVE_ARCH_STRCMP
154	/**
155	* strcmp - Compare two strings
156	* @cs: One string
157	* @ct: Another string
158	*/
159	int strcmp(const char * cs,const char * ct)
160	{
161	register signed char __res;
162
163	while (1) {
164	if ((__res = cs - ct++) != 0 \|\| !*cs++)
165	break;
166	}
167
168	return __res;
169	}
170	#endif
171
172	#ifndef __HAVE_ARCH_STRNCMP
173	/**
174	* strncmp - Compare two length-limited strings
175	* @cs: One string
176	* @ct: Another string
177	* @count: The maximum number of bytes to compare
178	*/
179	int strncmp(const char * cs,const char * ct,size_t count)
180	{
181	register signed char __res = 0;
182
183	while (count) {
184	if ((__res = cs - ct++) != 0 \|\| !*cs++)
185	break;
186	count--;
187	}
188
189	return __res;
190	}
191	#endif
192
193	#ifndef __HAVE_ARCH_STRCHR
194	/**
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
198	*/
199	char * strchr(const char * s, int c)
200	{
201	for(; *s != (char) c; ++s)
202	if (*s == '\0')
203	return NULL;
204	return (char *) s;
205	}
206	#endif
207
208	#ifndef __HAVE_ARCH_STRRCHR
209	/**
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
213	*/
214	char * strrchr(const char * s, int c)
215	{
216	const char *p = s + strlen(s);
217	do {
8bde7f77 WD	218	if (*p == (char)c)
8bde7f77 WD	219	return (char *)p;
c609719b WD	220	} while (--p >= s);
	221	return NULL;
	222	}
	223	#endif
	224
	225	#ifndef __HAVE_ARCH_STRLEN
	226	/**
	227	* strlen - Find the length of a string
	228	* @s: The string to be sized
	229	*/
	230	size_t strlen(const char * s)
	231	{
	232	const char *sc;
	233
	234	for (sc = s; *sc != '\0'; ++sc)
	235	/* nothing */;
	236	return sc - s;
	237	}
	238	#endif
	239
	240	#ifndef __HAVE_ARCH_STRNLEN
	241	/**
	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
	245	*/
	246	size_t strnlen(const char * s, size_t count)
	247	{
	248	const char *sc;
	249
	250	for (sc = s; count-- && *sc != '\0'; ++sc)
	251	/* nothing */;
	252	return sc - s;
	253	}
	254	#endif
	255
	256	#ifndef __HAVE_ARCH_STRDUP
	257	char * strdup(const char *s)
	258	{
	259	char *new;
	260
	261	if ((s == NULL) \|\|
	262	((new = malloc (strlen(s) + 1)) == NULL) ) {
	263	return NULL;
	264	}
	265
	266	strcpy (new, s);
	267	return new;
	268	}
	269	#endif
	270
	271	#ifndef __HAVE_ARCH_STRSPN
	272	/**
	273	* strspn - Calculate the length of the initial substring of @s which only
53677ef1	274	* contain letters in @accept
c609719b WD	275	* @s: The string to be searched
	276	* @accept: The string to search for
	277	*/
	278	size_t strspn(const char s, const char accept)
	279	{
	280	const char *p;
	281	const char *a;
	282	size_t count = 0;
	283
	284	for (p = s; *p != '\0'; ++p) {
	285	for (a = accept; *a != '\0'; ++a) {
	286	if (p == a)
	287	break;
	288	}
	289	if (*a == '\0')
	290	return count;
	291	++count;
	292	}
	293
	294	return count;
	295	}
	296	#endif
	297
	298	#ifndef __HAVE_ARCH_STRPBRK
	299	/**
	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
	303	*/
	304	char * strpbrk(const char * cs,const char * ct)
	305	{
	306	const char sc1,sc2;
	307
	308	for( sc1 = cs; *sc1 != '\0'; ++sc1) {
	309	for( sc2 = ct; *sc2 != '\0'; ++sc2) {
	310	if (sc1 == sc2)
	311	return (char *) sc1;
	312	}
	313	}
	314	return NULL;
	315	}
	316	#endif
	317
	318	#ifndef __HAVE_ARCH_STRTOK
	319	/**
	320	* strtok - Split a string into tokens
	321	* @s: The string to be searched
	322	* @ct: The characters to search for
	323	*
	324	* WARNING: strtok is deprecated, use strsep instead.
	325	*/
	326	char * strtok(char * s,const char * ct)
	327	{
	328	char sbegin, send;
	329
	330	sbegin = s ? s : ___strtok;
	331	if (!sbegin) {
	332	return NULL;
	333	}
	334	sbegin += strspn(sbegin,ct);
	335	if (*sbegin == '\0') {
	336	___strtok = NULL;
	337	return( NULL );
	338	}
339	send = strpbrk( sbegin, ct);
340	if (send && *send != '\0')
341	*send++ = '\0';
342	___strtok = send;
343	return (sbegin);
344	}
345	#endif
346
347	#ifndef __HAVE_ARCH_STRSEP
348	/**
349	* strsep - Split a string into tokens
350	* @s: The string to be searched
351	* @ct: The characters to search for
352	*
353	* strsep() updates @s to point after the token, ready for the next call.
354	*
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. ;)
358	*/
359	char * strsep(char *s, const char ct)
360	{
361	char sbegin = s, *end;
362
363	if (sbegin == NULL)
364	return NULL;
365
366	end = strpbrk(sbegin, ct);
367	if (end)
368	*end++ = '\0';
369	*s = end;
370
371	return sbegin;
372	}
373	#endif
374
c3f9d493 WD	375	#ifndef __HAVE_ARCH_STRSWAB
	376	/**
	377	* strswab - swap adjacent even and odd bytes in %NUL-terminated string
	378	* s: address of the string
	379	*
	380	* returns the address of the swapped string or NULL on error. If
	381	* string length is odd, last byte is untouched.
	382	*/
	383	char strswab(const char s)
	384	{
389db1f1	385	char p, q;
c3f9d493 WD	386
	387	if ((NULL == s) \|\| ('\0' == *s)) {
	388	return (NULL);
	389	}
	390
e5e98edd	391	for (p=(char )s, q=p+1; (p != '\0') && (*q != '\0'); p+=2, q+=2) {
c3f9d493	392	char tmp;
389db1f1 WD	393
	394	tmp = *p;
	395	p = q;
	396	*q = tmp;
c3f9d493 WD	397	}
	398
	399	return (char *) s;
	400	}
	401	#endif
	402
c609719b WD	403	#ifndef __HAVE_ARCH_MEMSET
	404	/**
	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.
	409	*
	410	* Do not use memset() to access IO space, use memset_io() instead.
	411	*/
	412	void * memset(void * s,int c,size_t count)
	413	{
e3ea948d AR	414	unsigned long sl = (unsigned long ) s;
	415	unsigned long cl = 0;
	416	char *s8;
	417	int i;
	418
	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++) {
	422	cl <<= 8;
	423	cl \|= c & 0xff;
	424	}
	425	while (count >= sizeof(*sl)) {
	426	*sl++ = cl;
	427	count -= sizeof(*sl);
	428	}
	429	}
	430	/* fill 8 bits at a time */
	431	s8 = (char *)sl;
c609719b	432	while (count--)
e3ea948d	433	*s8++ = c;
c609719b WD	434
	435	return s;
	436	}
	437	#endif
	438
	439	#ifndef __HAVE_ARCH_BCOPY
	440	/**
	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.
	445	*
	446	* Note that this is the same as memcpy(), with the arguments reversed.
	447	* memcpy() is the standard, bcopy() is a legacy BSD function.
	448	*
	449	* You should not use this function to access IO space, use memcpy_toio()
	450	* or memcpy_fromio() instead.
	451	*/
	452	char * bcopy(const char * src, char * dest, int count)
	453	{
	454	char *tmp = dest;
	455
	456	while (count--)
	457	tmp++ = src++;
	458
	459	return dest;
	460	}
	461	#endif
	462
	463	#ifndef __HAVE_ARCH_MEMCPY
	464	/**
	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.
	469	*
	470	* You should not use this function to access IO space, use memcpy_toio()
	471	* or memcpy_fromio() instead.
	472	*/
ecd830b8	473	void * memcpy(void dest, const void src, size_t count)
c609719b	474	{
ecd830b8 AR	475	unsigned long dl = (unsigned long )dest, sl = (unsigned long )src;
	476	char d8, s8;
	477
b038db85 MW	478	if (src == dest)
	479	return dest;
	480
ecd830b8 AR	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)) {
	484	dl++ = sl++;
	485	count -= sizeof(*dl);
	486	}
	487	}
	488	/* copy the reset one byte at a time */
	489	d8 = (char *)dl;
	490	s8 = (char *)sl;
c609719b	491	while (count--)
ecd830b8	492	d8++ = s8++;
c609719b WD	493
	494	return dest;
	495	}
	496	#endif
	497
	498	#ifndef __HAVE_ARCH_MEMMOVE
	499	/**
	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.
	504	*
	505	* Unlike memcpy(), memmove() copes with overlapping areas.
	506	*/
	507	void * memmove(void * dest,const void *src,size_t count)
	508	{
	509	char tmp, s;
	510
b038db85 MW	511	if (src == dest)
	512	return dest;
	513
c609719b WD	514	if (dest <= src) {
	515	tmp = (char *) dest;
	516	s = (char *) src;
	517	while (count--)
	518	tmp++ = s++;
	519	}
	520	else {
	521	tmp = (char *) dest + count;
	522	s = (char *) src + count;
	523	while (count--)
	524	--tmp = --s;
	525	}
	526
	527	return dest;
	528	}
	529	#endif
	530
	531	#ifndef __HAVE_ARCH_MEMCMP
	532	/**
	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.
	537	*/
	538	int memcmp(const void * cs,const void * ct,size_t count)
	539	{
	540	const unsigned char su1, su2;
	541	int res = 0;
	542
	543	for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
	544	if ((res = su1 - su2) != 0)
	545	break;
	546	return res;
	547	}
	548	#endif
	549
	550	#ifndef __HAVE_ARCH_MEMSCAN
	551	/**
	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.
	556	*
	557	* returns the address of the first occurrence of @c, or 1 byte past
	558	* the area if @c is not found
	559	*/
	560	void * memscan(void * addr, int c, size_t size)
	561	{
	562	unsigned char * p = (unsigned char *) addr;
	563
	564	while (size) {
	565	if (*p == c)
	566	return (void *) p;
	567	p++;
	568	size--;
	569	}
8bde7f77	570	return (void *) p;
c609719b WD	571	}
	572	#endif
	573
	574	#ifndef __HAVE_ARCH_STRSTR
	575	/**
	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
	579	*/
	580	char * strstr(const char * s1,const char * s2)
	581	{
	582	int l1, l2;
	583
	584	l2 = strlen(s2);
	585	if (!l2)
	586	return (char *) s1;
	587	l1 = strlen(s1);
	588	while (l1 >= l2) {
	589	l1--;
	590	if (!memcmp(s1,s2,l2))
	591	return (char *) s1;
	592	s1++;
	593	}
	594	return NULL;
	595	}
	596	#endif
	597
	598	#ifndef __HAVE_ARCH_MEMCHR
	599	/**
	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.
	604	*
	605	* returns the address of the first occurrence of @c, or %NULL
	606	* if @c is not found
	607	*/
	608	void memchr(const void s, int c, size_t n)
	609	{
	610	const unsigned char *p = s;
	611	while (n-- != 0) {
8bde7f77	612	if ((unsigned char)c == *p++) {
c609719b WD	613	return (void *)(p-1);
	614	}
	615	}
	616	return NULL;
	617	}
	618
	619	#endif
dfe64e2c SL	620	#ifndef __HAVE_ARCH_MEMCHR_INV
	621	static void check_bytes8(const u8 start, u8 value, unsigned int bytes)
	622	{
	623	while (bytes) {
	624	if (*start != value)
	625	return (void *)start;
	626	start++;
	627	bytes--;
	628	}
	629	return NULL;
	630	}
	631	/**
	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.
	636	*
	637	* returns the address of the first character other than @c, or %NULL
	638	* if the whole buffer contains just @c.
	639	*/
	640	void memchr_inv(const void start, int c, size_t bytes)
	641	{
	642	u8 value = c;
	643	u64 value64;
	644	unsigned int words, prefix;
	645
	646	if (bytes <= 16)
	647	return check_bytes8(start, value, bytes);
	648
	649	value64 = value;
	650	value64 \|= value64 << 8;
	651	value64 \|= value64 << 16;
	652	value64 \|= value64 << 32;
	653
	654	prefix = (unsigned long)start % 8;
	655	if (prefix) {
	656	u8 *r;
	657
	658	prefix = 8 - prefix;
	659	r = check_bytes8(start, value, prefix);
	660	if (r)
	661	return r;
	662	start += prefix;
	663	bytes -= prefix;
	664	}
	665
	666	words = bytes / 8;
	667
	668	while (words) {
	669	if ((u64 )start != value64)
	670	return check_bytes8(start, value, 8);
	671	start += 8;
	672	words--;
	673	}
	674
	675	return check_bytes8(start, value, bytes % 8);
	676	}
	677	#endif