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author | Timothy Pearson <tpearson@raptorengineering.com> | 2017-08-23 14:45:25 -0500 |
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committer | Timothy Pearson <tpearson@raptorengineering.com> | 2017-08-23 14:45:25 -0500 |
commit | fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204 (patch) | |
tree | 22962a4387943edc841c72a4e636a068c66d58fd /lib/string.c | |
download | ast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.zip ast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.tar.gz |
Initial import of modified Linux 2.6.28 tree
Original upstream URL:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y
Diffstat (limited to 'lib/string.c')
-rw-r--r-- | lib/string.c | 689 |
1 files changed, 689 insertions, 0 deletions
diff --git a/lib/string.c b/lib/string.c new file mode 100644 index 0000000..b19b87a --- /dev/null +++ b/lib/string.c @@ -0,0 +1,689 @@ +/* + * 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 = 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_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 + * @dest: Where to copy the string to + * @src: Where to copy the string from + */ +#undef strcpy +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. + * + * In the case where the length of @src is less than that of + * count, the remainder of @dest will be padded with %NUL. + * + */ +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 + */ +#undef strcat +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 + */ +#undef strcmp +int strcmp(const char *cs, const char *ct) +{ + 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) +{ + 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 + +/** + * strstrip - 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 *strstrip(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'; + + while (*s && isspace(*s)) + s++; + + return s; +} +EXPORT_SYMBOL(strstrip); + +#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 + +#ifndef __HAVE_ARCH_STRCSPN +/** + * 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); +#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; +} +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; + char *end; + + if (sbegin == NULL) + return NULL; + + end = strpbrk(sbegin, 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); + +#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 = 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 = dest; + const char *s = 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; + const char *s; + + if (dest <= src) { + tmp = dest; + s = src; + while (count--) + *tmp++ = *s++; + } else { + tmp = dest; + tmp += count; + s = src; + s += count; + while (count--) + *--tmp = *--s; + } + return dest; +} +EXPORT_SYMBOL(memmove); +#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. + */ +#undef memcmp +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; +} +EXPORT_SYMBOL(memcmp); +#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 = addr; + + while (size) { + if (*p == c) + return (void *)p; + p++; + size--; + } + return (void *)p; +} +EXPORT_SYMBOL(memscan); +#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; +} +EXPORT_SYMBOL(strstr); +#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; +} +EXPORT_SYMBOL(memchr); +#endif |