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/*
* 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.
*/
#include "ctypes.h"
#include "com_type.h"
#include "util.h"
#include "string.h"
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;
if ((NULL == s) || ('\0' == *s)) {
return (NULL);
}
for (p = ((char *)s + 1); '\0' != *p; p += 2) {
char tmp;
tmp = *(p-1);
*(p-1) = *p;
*p = 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)
{
char *xs = (char *) s;
while (count--)
*xs++ = 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)
{
char *tmp = (char *) dest, *s = (char *) src;
while (count--)
*tmp++ = *s++;
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 (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
/*
* Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <string.h>
/*
* Copy src to string dst of size siz. At most siz-1 characters
* will be copied. Always NUL terminates (unless siz == 0).
* Returns strlen(src); if retval >= siz, truncation occurred.
*/
size_t
strlcpy(char *dst, const char *src, size_t siz)
{
char *d = dst;
const char *s = src;
size_t n = siz;
/* Copy as many bytes as will fit */
if (n != 0) {
while (--n != 0) {
if ((*d++ = *s++) == '\0')
break;
}
}
/* Not enough room in dst, add NUL and traverse rest of src */
if (n == 0) {
if (siz != 0)
*d = '\0'; /* NUL-terminate dst */
while (*s++)
;
}
return(s - src - 1); /* count does not include NUL */
}
/*
* Appends src to string dst of size siz (unlike strncat, siz is the
* full size of dst, not space left). At most siz-1 characters
* will be copied. Always NUL terminates (unless siz <= strlen(dst)).
* Returns strlen(src) + MIN(siz, strlen(initial dst)).
* If retval >= siz, truncation occurred.
*/
size_t
strlcat(char *dst, const char *src, size_t siz)
{
char *d = dst;
const char *s = src;
size_t n = siz;
size_t dlen;
/* Find the end of dst and adjust bytes left but don't go past end */
while (n-- != 0 && *d != '\0')
d++;
dlen = d - dst;
n = siz - dlen;
if (n == 0)
return(dlen + strlen(s));
while (*s != '\0') {
if (n != 1) {
*d++ = *s;
n--;
}
s++;
}
*d = '\0';
return(dlen + (s - src)); /* count does not include NUL */
}