601 lines · 11.8 KB · C
RawDownload
/* *  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 <ioe@informatik.tu-chemnitz.de> * -  Added strsep() which will replace strtok() soon (because strsep() is *    reentrant and should be faster). Use only strsep() in new code, please. * * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>, *                    Matthew Hawkins <matt@mh.dropbear.id.au> * -  Kissed strtok() goodbye */ #include <linux/types.h>#include <linux/string.h>#include <linux/ctype.h>#include <linux/module.h> #ifndef __HAVE_ARCH_STRNICMP/** * strnicmp - Case insensitive, length-limited string comparison * @s1: One string * @s2: The other string * @len: the maximum number of characters to compare */int strnicmp(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;} EXPORT_SYMBOL(strnicmp);#endif #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;}EXPORT_SYMBOL(strcpy);#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 * * 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) {		if ((*tmp = *src) != 0) src++;		tmp++;		count--;	}	return dest;}EXPORT_SYMBOL(strncpy);#endif #ifndef __HAVE_ARCH_STRLCPY/** * strlcpy - Copy a %NUL terminated string into a sized buffer * @dest: Where to copy the string to * @src: Where to copy the string from * @size: size of destination buffer * * Compatible with *BSD: the result is always a valid * NUL-terminated string that fits in the buffer (unless, * of course, the buffer size is zero). It does not pad * out the result like strncpy() does. */size_t strlcpy(char *dest, const char *src, size_t size){	size_t ret = strlen(src); 	if (size) {		size_t len = (ret >= size) ? size-1 : ret;		memcpy(dest, src, len);		dest[len] = '\0';	}	return ret;}EXPORT_SYMBOL(strlcpy);#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;}EXPORT_SYMBOL(strcat);#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++) != 0) {			if (--count == 0) {				*dest = '\0';				break;			}		}	} 	return tmp;}EXPORT_SYMBOL(strncat);#endif #ifndef __HAVE_ARCH_STRLCAT/** * strlcat - 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 size of the destination buffer. */size_t strlcat(char *dest, const char *src, size_t count){	size_t dsize = strlen(dest);	size_t len = strlen(src);	size_t res = dsize + len; 	/* This would be a bug */	BUG_ON(dsize >= count); 	dest += dsize;	count -= dsize;	if (len >= count)		len = count-1;	memcpy(dest, src, len);	dest[len] = 0;	return res;}EXPORT_SYMBOL(strlcat);#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;}EXPORT_SYMBOL(strcmp);#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;}EXPORT_SYMBOL(strncmp);#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;}EXPORT_SYMBOL(strchr);#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;}EXPORT_SYMBOL(strrchr);#endif #ifndef __HAVE_ARCH_STRNCHR/** * strnchr - Find a character in a length limited string * @s: The string to be searched * @count: The number of characters to be searched * @c: The character to search for */char *strnchr(const char *s, size_t count, int c){	for (; count-- && *s != '\0'; ++s)		if (*s == (char) c)			return (char *) s;	return NULL;}EXPORT_SYMBOL(strnchr);#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;}EXPORT_SYMBOL(strlen);#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;}EXPORT_SYMBOL(strnlen);#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;} EXPORT_SYMBOL(strspn);#endif /** * strcspn - Calculate the length of the initial substring of @s which does * 	not contain letters in @reject * @s: The string to be searched * @reject: The string to avoid */size_t strcspn(const char *s, const char *reject){	const char *p;	const char *r;	size_t count = 0; 	for (p = s; *p != '\0'; ++p) {		for (r = reject; *r != '\0'; ++r) {			if (*p == *r)				return count;		}		++count;	} 	return count;}	EXPORT_SYMBOL(strcspn); #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;}EXPORT_SYMBOL(strpbrk);#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;} EXPORT_SYMBOL(strsep);#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){	char *xs = (char *) s; 	while (count--)		*xs++ = c; 	return s;}EXPORT_SYMBOL(memset);#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){	char *tmp = (char *) dest, *s = (char *) src; 	while (count--)		*tmp++ = *s++; 	return dest;}EXPORT_SYMBOL(memcpy);#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 (dest <= src) {		tmp = (char *) dest;		s = (char *) src;		while (count--)			*tmp++ = *s++;		}	else {		tmp = (char *) dest + count;		s = (char *) src + count;

Lines 1–500 of 601.