| /* |
| * 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 <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_STRLCPY |
| /** |
| * strlcpy - Copy a C-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; |
| } |
| #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_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; |
| } |
| #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_MEMSCPY |
| /** |
| * memscpy - Copy one area of memory to another |
| * @dest: Where to copy to |
| * @src: Where to copy from |
| * @dst_size: The size of destination buffer area |
| * @copy_size: The size of source buffer area |
| * |
| * You should not use this function where memcpy |
| * was used to copy null terminated buffer, the |
| * replacement function is strlcpy() and strlcat() |
| * depending on situation. |
| * |
| * The aim of memscpy() is to prevent buffer overflow |
| * by taking both destination buffer size and source |
| * buffer size. |
| */ |
| size_t memscpy(void *dest, size_t dst_size, const void *src, size_t copy_size) |
| { |
| size_t min_size = dst_size < copy_size ? dst_size : copy_size; |
| memcpy(dest, src, min_size); |
| return min_size; |
| } |
| #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 |