diff options
Diffstat (limited to 'lib/string.c')
| -rw-r--r-- | lib/string.c | 423 |
1 files changed, 329 insertions, 94 deletions
diff --git a/lib/string.c b/lib/string.c index d886ef157c1..992bf30af75 100644 --- a/lib/string.c +++ b/lib/string.c @@ -22,7 +22,10 @@ #include <linux/types.h> #include <linux/string.h> #include <linux/ctype.h> -#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/bug.h> +#include <linux/errno.h> #ifndef __HAVE_ARCH_STRNICMP /** @@ -36,29 +39,54 @@ 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); - } + if (!len) + return 0; + + do { + c1 = *s1++; + c2 = *s2++; + if (!c1 || !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_STRCASECMP +int strcasecmp(const char *s1, const char *s2) +{ + int c1, c2; + + do { + c1 = tolower(*s1++); + c2 = tolower(*s2++); + } while (c1 == c2 && c1 != 0); + return c1 - c2; +} +EXPORT_SYMBOL(strcasecmp); +#endif + +#ifndef __HAVE_ARCH_STRNCASECMP +int strncasecmp(const char *s1, const char *s2, size_t n) +{ + int c1, c2; + + do { + c1 = tolower(*s1++); + c2 = tolower(*s2++); + } while ((--n > 0) && c1 == c2 && c1 != 0); + return c1 - c2; +} +EXPORT_SYMBOL(strncasecmp); +#endif + #ifndef __HAVE_ARCH_STRCPY /** * strcpy - Copy a %NUL terminated string @@ -66,7 +94,7 @@ EXPORT_SYMBOL(strnicmp); * @src: Where to copy the string from */ #undef strcpy -char * strcpy(char * dest,const char *src) +char *strcpy(char *dest, const char *src) { char *tmp = dest; @@ -79,7 +107,7 @@ EXPORT_SYMBOL(strcpy); #ifndef __HAVE_ARCH_STRNCPY /** - * strncpy - Copy a length-limited, %NUL-terminated string + * strncpy - Copy a length-limited, C-string * @dest: Where to copy the string to * @src: Where to copy the string from * @count: The maximum number of bytes to copy @@ -91,12 +119,13 @@ EXPORT_SYMBOL(strcpy); * count, the remainder of @dest will be padded with %NUL. * */ -char * strncpy(char * dest,const char *src,size_t count) +char *strncpy(char *dest, const char *src, size_t count) { char *tmp = dest; while (count) { - if ((*tmp = *src) != 0) src++; + if ((*tmp = *src) != 0) + src++; tmp++; count--; } @@ -107,7 +136,7 @@ EXPORT_SYMBOL(strncpy); #ifndef __HAVE_ARCH_STRLCPY /** - * strlcpy - Copy a %NUL terminated string into a sized buffer + * 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 @@ -122,7 +151,7 @@ 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; + size_t len = (ret >= size) ? size - 1 : ret; memcpy(dest, src, len); dest[len] = '\0'; } @@ -138,7 +167,7 @@ EXPORT_SYMBOL(strlcpy); * @src: The string to append to it */ #undef strcat -char * strcat(char * dest, const char * src) +char *strcat(char *dest, const char *src) { char *tmp = dest; @@ -146,7 +175,6 @@ char * strcat(char * dest, const char * src) dest++; while ((*dest++ = *src++) != '\0') ; - return tmp; } EXPORT_SYMBOL(strcat); @@ -154,15 +182,15 @@ EXPORT_SYMBOL(strcat); #ifndef __HAVE_ARCH_STRNCAT /** - * strncat - Append a length-limited, %NUL-terminated string to another + * strncat - Append a length-limited, C-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 + * Note that in contrast to strncpy(), strncat() ensures the result is * terminated. */ -char * strncat(char *dest, const char *src, size_t count) +char *strncat(char *dest, const char *src, size_t count) { char *tmp = dest; @@ -176,7 +204,6 @@ char * strncat(char *dest, const char *src, size_t count) } } } - return tmp; } EXPORT_SYMBOL(strncat); @@ -184,7 +211,7 @@ EXPORT_SYMBOL(strncat); #ifndef __HAVE_ARCH_STRLCAT /** - * strlcat - Append a length-limited, %NUL-terminated string to another + * strlcat - Append a length-limited, C-string to another * @dest: The string to be appended to * @src: The string to append to it * @count: The size of the destination buffer. @@ -216,16 +243,19 @@ EXPORT_SYMBOL(strlcat); * @ct: Another string */ #undef strcmp -int strcmp(const char * cs,const char * ct) +int strcmp(const char *cs, const char *ct) { - register signed char __res; + unsigned char c1, c2; while (1) { - if ((__res = *cs - *ct++) != 0 || !*cs++) + c1 = *cs++; + c2 = *ct++; + if (c1 != c2) + return c1 < c2 ? -1 : 1; + if (!c1) break; } - - return __res; + return 0; } EXPORT_SYMBOL(strcmp); #endif @@ -237,17 +267,20 @@ EXPORT_SYMBOL(strcmp); * @ct: Another string * @count: The maximum number of bytes to compare */ -int strncmp(const char * cs,const char * ct,size_t count) +int strncmp(const char *cs, const char *ct, size_t count) { - register signed char __res = 0; + unsigned char c1, c2; while (count) { - if ((__res = *cs - *ct++) != 0 || !*cs++) + c1 = *cs++; + c2 = *ct++; + if (c1 != c2) + return c1 < c2 ? -1 : 1; + if (!c1) break; count--; } - - return __res; + return 0; } EXPORT_SYMBOL(strncmp); #endif @@ -258,23 +291,41 @@ EXPORT_SYMBOL(strncmp); * @s: The string to be searched * @c: The character to search for */ -char * strchr(const char * s, int c) +char *strchr(const char *s, int c) { - for(; *s != (char) c; ++s) + for (; *s != (char)c; ++s) if (*s == '\0') return NULL; - return (char *) s; + return (char *)s; } EXPORT_SYMBOL(strchr); #endif +#ifndef __HAVE_ARCH_STRCHRNUL +/** + * strchrnul - Find and return a character in a string, or end of string + * @s: The string to be searched + * @c: The character to search for + * + * Returns pointer to first occurrence of 'c' in s. If c is not found, then + * return a pointer to the null byte at the end of s. + */ +char *strchrnul(const char *s, int c) +{ + while (*s && *s != (char)c) + s++; + return (char *)s; +} +EXPORT_SYMBOL(strchrnul); +#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) +char *strrchr(const char *s, int c) { const char *p = s + strlen(s); do { @@ -296,19 +347,59 @@ EXPORT_SYMBOL(strrchr); char *strnchr(const char *s, size_t count, int c) { for (; count-- && *s != '\0'; ++s) - if (*s == (char) c) - return (char *) s; + if (*s == (char)c) + return (char *)s; return NULL; } EXPORT_SYMBOL(strnchr); #endif +/** + * skip_spaces - Removes leading whitespace from @str. + * @str: The string to be stripped. + * + * Returns a pointer to the first non-whitespace character in @str. + */ +char *skip_spaces(const char *str) +{ + while (isspace(*str)) + ++str; + return (char *)str; +} +EXPORT_SYMBOL(skip_spaces); + +/** + * strim - Removes leading and trailing whitespace from @s. + * @s: The string to be stripped. + * + * Note that the first trailing whitespace is replaced with a %NUL-terminator + * in the given string @s. Returns a pointer to the first non-whitespace + * character in @s. + */ +char *strim(char *s) +{ + size_t size; + char *end; + + size = strlen(s); + if (!size) + return s; + + end = s + size - 1; + while (end >= s && isspace(*end)) + end--; + *(end + 1) = '\0'; + + return skip_spaces(s); +} +EXPORT_SYMBOL(strim); + #ifndef __HAVE_ARCH_STRLEN /** * strlen - Find the length of a string * @s: The string to be sized */ -size_t strlen(const char * s) +size_t strlen(const char *s) { const char *sc; @@ -325,7 +416,7 @@ EXPORT_SYMBOL(strlen); * @s: The string to be sized * @count: The maximum number of bytes to search */ -size_t strnlen(const char * s, size_t count) +size_t strnlen(const char *s, size_t count) { const char *sc; @@ -338,8 +429,7 @@ EXPORT_SYMBOL(strnlen); #ifndef __HAVE_ARCH_STRSPN /** - * strspn - Calculate the length of the initial substring of @s which only - * contain letters in @accept + * 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 */ @@ -358,16 +448,15 @@ size_t strspn(const char *s, const char *accept) return count; ++count; } - return count; } EXPORT_SYMBOL(strspn); #endif +#ifndef __HAVE_ARCH_STRCSPN /** - * strcspn - Calculate the length of the initial substring of @s which does - * not contain letters in @reject + * 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 */ @@ -384,10 +473,10 @@ size_t strcspn(const char *s, const char *reject) } ++count; } - return count; -} +} EXPORT_SYMBOL(strcspn); +#endif #ifndef __HAVE_ARCH_STRPBRK /** @@ -395,14 +484,14 @@ EXPORT_SYMBOL(strcspn); * @cs: The string to be searched * @ct: The characters to search for */ -char * strpbrk(const char * cs,const char * ct) +char *strpbrk(const char *cs, const char *ct) { - const char *sc1,*sc2; + const char *sc1, *sc2; - for( sc1 = cs; *sc1 != '\0'; ++sc1) { - for( sc2 = ct; *sc2 != '\0'; ++sc2) { + for (sc1 = cs; *sc1 != '\0'; ++sc1) { + for (sc2 = ct; *sc2 != '\0'; ++sc2) { if (*sc1 == *sc2) - return (char *) sc1; + return (char *)sc1; } } return NULL; @@ -422,9 +511,10 @@ EXPORT_SYMBOL(strpbrk); * 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 *strsep(char **s, const char *ct) { - char *sbegin = *s, *end; + char *sbegin = *s; + char *end; if (sbegin == NULL) return NULL; @@ -433,13 +523,67 @@ char * strsep(char **s, const char *ct) if (end) *end++ = '\0'; *s = end; - return sbegin; } - EXPORT_SYMBOL(strsep); #endif +/** + * sysfs_streq - return true if strings are equal, modulo trailing newline + * @s1: one string + * @s2: another string + * + * This routine returns true iff two strings are equal, treating both + * NUL and newline-then-NUL as equivalent string terminations. It's + * geared for use with sysfs input strings, which generally terminate + * with newlines but are compared against values without newlines. + */ +bool sysfs_streq(const char *s1, const char *s2) +{ + while (*s1 && *s1 == *s2) { + s1++; + s2++; + } + + if (*s1 == *s2) + return true; + if (!*s1 && *s2 == '\n' && !s2[1]) + return true; + if (*s1 == '\n' && !s1[1] && !*s2) + return true; + return false; +} +EXPORT_SYMBOL(sysfs_streq); + +/** + * strtobool - convert common user inputs into boolean values + * @s: input string + * @res: result + * + * This routine returns 0 iff the first character is one of 'Yy1Nn0'. + * Otherwise it will return -EINVAL. Value pointed to by res is + * updated upon finding a match. + */ +int strtobool(const char *s, bool *res) +{ + switch (s[0]) { + case 'y': + case 'Y': + case '1': + *res = true; + break; + case 'n': + case 'N': + case '0': + *res = false; + break; + default: + return -EINVAL; + } + return 0; +} +EXPORT_SYMBOL(strtobool); + #ifndef __HAVE_ARCH_MEMSET /** * memset - Fill a region of memory with the given value @@ -449,13 +593,12 @@ EXPORT_SYMBOL(strsep); * * Do not use memset() to access IO space, use memset_io() instead. */ -void * memset(void * s,int c,size_t count) +void *memset(void *s, int c, size_t count) { - char *xs = (char *) s; + char *xs = s; while (count--) *xs++ = c; - return s; } EXPORT_SYMBOL(memset); @@ -471,13 +614,13 @@ EXPORT_SYMBOL(memset); * 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) +void *memcpy(void *dest, const void *src, size_t count) { - char *tmp = (char *) dest, *s = (char *) src; + char *tmp = dest; + const char *s = src; while (count--) *tmp++ = *s++; - return dest; } EXPORT_SYMBOL(memcpy); @@ -492,23 +635,24 @@ EXPORT_SYMBOL(memcpy); * * Unlike memcpy(), memmove() copes with overlapping areas. */ -void * memmove(void * dest,const void *src,size_t count) +void *memmove(void *dest, const void *src, size_t count) { - char *tmp, *s; + char *tmp; + const char *s; if (dest <= src) { - tmp = (char *) dest; - s = (char *) src; + tmp = dest; + s = src; while (count--) *tmp++ = *s++; - } - else { - tmp = (char *) dest + count; - s = (char *) src + count; + } else { + tmp = dest; + tmp += count; + s = src; + s += count; while (count--) *--tmp = *--s; - } - + } return dest; } EXPORT_SYMBOL(memmove); @@ -522,12 +666,12 @@ EXPORT_SYMBOL(memmove); * @count: The size of the area. */ #undef memcmp -int memcmp(const void * cs,const void * ct,size_t count) +__visible 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--) + for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--) if ((res = *su1 - *su2) != 0) break; return res; @@ -545,17 +689,17 @@ EXPORT_SYMBOL(memcmp); * 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) +void *memscan(void *addr, int c, size_t size) { - unsigned char * p = (unsigned char *) addr; + unsigned char *p = addr; while (size) { if (*p == c) - return (void *) p; + return (void *)p; p++; size--; } - return (void *) p; + return (void *)p; } EXPORT_SYMBOL(memscan); #endif @@ -566,18 +710,18 @@ EXPORT_SYMBOL(memscan); * @s1: The string to be searched * @s2: The string to search for */ -char * strstr(const char * s1,const char * s2) +char *strstr(const char *s1, const char *s2) { - int l1, l2; + size_t l1, l2; l2 = strlen(s2); if (!l2) - return (char *) s1; + return (char *)s1; l1 = strlen(s1); while (l1 >= l2) { l1--; - if (!memcmp(s1,s2,l2)) - return (char *) s1; + if (!memcmp(s1, s2, l2)) + return (char *)s1; s1++; } return NULL; @@ -585,6 +729,31 @@ char * strstr(const char * s1,const char * s2) EXPORT_SYMBOL(strstr); #endif +#ifndef __HAVE_ARCH_STRNSTR +/** + * strnstr - Find the first substring in a length-limited string + * @s1: The string to be searched + * @s2: The string to search for + * @len: the maximum number of characters to search + */ +char *strnstr(const char *s1, const char *s2, size_t len) +{ + size_t l2; + + l2 = strlen(s2); + if (!l2) + return (char *)s1; + while (len >= l2) { + len--; + if (!memcmp(s1, s2, l2)) + return (char *)s1; + s1++; + } + return NULL; +} +EXPORT_SYMBOL(strnstr); +#endif + #ifndef __HAVE_ARCH_MEMCHR /** * memchr - Find a character in an area of memory. @@ -600,10 +769,76 @@ 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 (void *)(p - 1); } } return NULL; } EXPORT_SYMBOL(memchr); #endif + +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; +#if defined(ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64 + value64 *= 0x0101010101010101; +#elif defined(ARCH_HAS_FAST_MULTIPLIER) + value64 *= 0x01010101; + value64 |= value64 << 32; +#else + value64 |= value64 << 8; + value64 |= value64 << 16; + value64 |= value64 << 32; +#endif + + 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); +} +EXPORT_SYMBOL(memchr_inv); |