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.
17 * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>,
18 * Matthew Hawkins <matt@mh.dropbear.id.au>
19 * - Kissed strtok() goodbye
24 #include <linux/types.h>
25 #include <linux/string.h>
26 #include <linux/ctype.h>
27 #include <linux/module.h>
29 #ifndef __HAVE_ARCH_STRNICMP
31 * strnicmp - Case insensitive, length-limited string comparison
33 * @s2: The other string
34 * @len: the maximum number of characters to compare
36 int strnicmp(const char *s1, const char *s2, size_t len)
38 /* Yes, Virginia, it had better be unsigned */
58 return (int)c1 - (int)c2;
61 EXPORT_SYMBOL(strnicmp);
64 #ifndef __HAVE_ARCH_STRCPY
66 * strcpy - Copy a %NUL terminated string
67 * @dest: Where to copy the string to
68 * @src: Where to copy the string from
70 char * strcpy(char * dest,const char *src)
74 while ((*dest++ = *src++) != '\0')
80 #ifndef __HAVE_ARCH_STRNCPY
82 * strncpy - Copy a length-limited, %NUL-terminated string
83 * @dest: Where to copy the string to
84 * @src: Where to copy the string from
85 * @count: The maximum number of bytes to copy
87 * The result is not %NUL-terminated if the source exceeds
90 char * strncpy(char * dest,const char *src,size_t count)
95 if ((*tmp = *src) != 0) src++;
103 #ifndef __HAVE_ARCH_STRLCPY
105 * strlcpy - Copy a %NUL terminated string into a sized buffer
106 * @dest: Where to copy the string to
107 * @src: Where to copy the string from
108 * @size: size of destination buffer
110 * Compatible with *BSD: the result is always a valid
111 * NUL-terminated string that fits in the buffer (unless,
112 * of course, the buffer size is zero). It does not pad
113 * out the result like strncpy() does.
115 size_t strlcpy(char *dest, const char *src, size_t size)
117 size_t ret = strlen(src);
120 size_t len = (ret >= size) ? size-1 : ret;
121 memcpy(dest, src, len);
126 EXPORT_SYMBOL(strlcpy);
129 #ifndef __HAVE_ARCH_STRCAT
131 * strcat - Append one %NUL-terminated string to another
132 * @dest: The string to be appended to
133 * @src: The string to append to it
135 char * strcat(char * dest, const char * src)
141 while ((*dest++ = *src++) != '\0')
148 #ifndef __HAVE_ARCH_STRNCAT
150 * strncat - Append a length-limited, %NUL-terminated string to another
151 * @dest: The string to be appended to
152 * @src: The string to append to it
153 * @count: The maximum numbers of bytes to copy
155 * Note that in contrast to strncpy, strncat ensures the result is
158 char * strncat(char *dest, const char *src, size_t count)
165 while ((*dest++ = *src++)) {
177 #ifndef __HAVE_ARCH_STRLCAT
179 * strlcat - Append a length-limited, %NUL-terminated string to another
180 * @dest: The string to be appended to
181 * @src: The string to append to it
182 * @count: The size of the destination buffer.
184 size_t strlcat(char *dest, const char *src, size_t count)
186 size_t dsize = strlen(dest);
187 size_t len = strlen(src);
188 size_t res = dsize + len;
190 /* This would be a bug */
191 BUG_ON(dsize >= count);
197 memcpy(dest, src, len);
201 EXPORT_SYMBOL(strlcat);
204 #ifndef __HAVE_ARCH_STRCMP
206 * strcmp - Compare two strings
208 * @ct: Another string
210 int strcmp(const char * cs,const char * ct)
212 register signed char __res;
215 if ((__res = *cs - *ct++) != 0 || !*cs++)
223 #ifndef __HAVE_ARCH_STRNCMP
225 * strncmp - Compare two length-limited strings
227 * @ct: Another string
228 * @count: The maximum number of bytes to compare
230 int strncmp(const char * cs,const char * ct,size_t count)
232 register signed char __res = 0;
235 if ((__res = *cs - *ct++) != 0 || !*cs++)
244 #ifndef __HAVE_ARCH_STRCHR
246 * strchr - Find the first occurrence of a character in a string
247 * @s: The string to be searched
248 * @c: The character to search for
250 char * strchr(const char * s, int c)
252 for(; *s != (char) c; ++s)
259 #ifndef __HAVE_ARCH_STRRCHR
261 * strrchr - Find the last occurrence of a character in a string
262 * @s: The string to be searched
263 * @c: The character to search for
265 char * strrchr(const char * s, int c)
267 const char *p = s + strlen(s);
276 #ifndef __HAVE_ARCH_STRNCHR
278 * strnchr - Find a character in a length limited string
279 * @s: The string to be searched
280 * @count: The number of characters to be searched
281 * @c: The character to search for
283 char *strnchr(const char *s, size_t count, int c)
285 for (; count-- && *s != '\0'; ++s)
292 #ifndef __HAVE_ARCH_STRLEN
294 * strlen - Find the length of a string
295 * @s: The string to be sized
297 size_t strlen(const char * s)
301 for (sc = s; *sc != '\0'; ++sc)
307 #ifndef __HAVE_ARCH_STRNLEN
309 * strnlen - Find the length of a length-limited string
310 * @s: The string to be sized
311 * @count: The maximum number of bytes to search
313 size_t strnlen(const char * s, size_t count)
317 for (sc = s; count-- && *sc != '\0'; ++sc)
323 #ifndef __HAVE_ARCH_STRSPN
325 * strspn - Calculate the length of the initial substring of @s which only
326 * contain letters in @accept
327 * @s: The string to be searched
328 * @accept: The string to search for
330 size_t strspn(const char *s, const char *accept)
336 for (p = s; *p != '\0'; ++p) {
337 for (a = accept; *a != '\0'; ++a) {
349 EXPORT_SYMBOL(strspn);
353 * strcspn - Calculate the length of the initial substring of @s which does
354 * not contain letters in @reject
355 * @s: The string to be searched
356 * @reject: The string to avoid
358 size_t strcspn(const char *s, const char *reject)
364 for (p = s; *p != '\0'; ++p) {
365 for (r = reject; *r != '\0'; ++r) {
375 #ifndef __HAVE_ARCH_STRPBRK
377 * strpbrk - Find the first occurrence of a set of characters
378 * @cs: The string to be searched
379 * @ct: The characters to search for
381 char * strpbrk(const char * cs,const char * ct)
383 const char *sc1,*sc2;
385 for( sc1 = cs; *sc1 != '\0'; ++sc1) {
386 for( sc2 = ct; *sc2 != '\0'; ++sc2) {
395 #ifndef __HAVE_ARCH_STRSEP
397 * strsep - Split a string into tokens
398 * @s: The string to be searched
399 * @ct: The characters to search for
401 * strsep() updates @s to point after the token, ready for the next call.
403 * It returns empty tokens, too, behaving exactly like the libc function
404 * of that name. In fact, it was stolen from glibc2 and de-fancy-fied.
405 * Same semantics, slimmer shape. ;)
407 char * strsep(char **s, const char *ct)
409 char *sbegin = *s, *end;
414 end = strpbrk(sbegin, ct);
422 EXPORT_SYMBOL(strsep);
425 #ifndef __HAVE_ARCH_MEMSET
427 * memset - Fill a region of memory with the given value
428 * @s: Pointer to the start of the area.
429 * @c: The byte to fill the area with
430 * @count: The size of the area.
432 * Do not use memset() to access IO space, use memset_io() instead.
434 void * memset(void * s,int c,size_t count)
436 char *xs = (char *) s;
445 #ifndef __HAVE_ARCH_BCOPY
447 * bcopy - Copy one area of memory to another
448 * @src: Where to copy from
449 * @dest: Where to copy to
450 * @count: The size of the area.
452 * Note that this is the same as memcpy(), with the arguments reversed.
453 * memcpy() is the standard, bcopy() is a legacy BSD function.
455 * You should not use this function to access IO space, use memcpy_toio()
456 * or memcpy_fromio() instead.
458 void bcopy(const void * srcp, void * destp, size_t count)
460 const char *src = srcp;
468 #ifndef __HAVE_ARCH_MEMCPY
470 * memcpy - Copy one area of memory to another
471 * @dest: Where to copy to
472 * @src: Where to copy from
473 * @count: The size of the area.
475 * You should not use this function to access IO space, use memcpy_toio()
476 * or memcpy_fromio() instead.
478 void * memcpy(void * dest,const void *src,size_t count)
480 char *tmp = (char *) dest, *s = (char *) src;
489 #ifndef __HAVE_ARCH_MEMMOVE
491 * memmove - Copy one area of memory to another
492 * @dest: Where to copy to
493 * @src: Where to copy from
494 * @count: The size of the area.
496 * Unlike memcpy(), memmove() copes with overlapping areas.
498 void * memmove(void * dest,const void *src,size_t count)
509 tmp = (char *) dest + count;
510 s = (char *) src + count;
519 #ifndef __HAVE_ARCH_MEMCMP
521 * memcmp - Compare two areas of memory
522 * @cs: One area of memory
523 * @ct: Another area of memory
524 * @count: The size of the area.
526 int memcmp(const void * cs,const void * ct,size_t count)
528 const unsigned char *su1, *su2;
531 for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
532 if ((res = *su1 - *su2) != 0)
538 #ifndef __HAVE_ARCH_MEMSCAN
540 * memscan - Find a character in an area of memory.
541 * @addr: The memory area
542 * @c: The byte to search for
543 * @size: The size of the area.
545 * returns the address of the first occurrence of @c, or 1 byte past
546 * the area if @c is not found
548 void * memscan(void * addr, int c, size_t size)
550 unsigned char * p = (unsigned char *) addr;
562 #ifndef __HAVE_ARCH_STRSTR
564 * strstr - Find the first substring in a %NUL terminated string
565 * @s1: The string to be searched
566 * @s2: The string to search for
568 char * strstr(const char * s1,const char * s2)
578 if (!memcmp(s1,s2,l2))
586 #ifndef __HAVE_ARCH_MEMCHR
588 * memchr - Find a character in an area of memory.
589 * @s: The memory area
590 * @c: The byte to search for
591 * @n: The size of the area.
593 * returns the address of the first occurrence of @c, or %NULL
596 void *memchr(const void *s, int c, size_t n)
598 const unsigned char *p = s;
600 if ((unsigned char)c == *p++) {
601 return (void *)(p-1);