lib/kstrtox.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Convert integer string representation to an integer.
  * If an integer doesn't fit into specified type, -E is returned.
  *
  * Integer starts with optional sign.
  * kstrtou*() functions do not accept sign "-".
  *
  * Radix 0 means autodetection: leading "0x" implies radix 16,
  * leading "0" implies radix 8, otherwise radix is 10.
  * Autodetection hints work after optional sign, but not before.
  *
  * If -E is returned, result is not touched.
  */
 #include <linux/ctype.h>
 #include <linux/errno.h>
 #include <linux/export.h>
 #include <linux/kstrtox.h>
 #include <linux/math64.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>

 #include "kstrtox.h"

 const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
 {
 	if (*base == 0) {
 		if (s[0] == '0') {
 			if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
 				*base = 16;
 			else
 				*base = 8;
 		} else
 			*base = 10;
 	}
 	if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
 		s += 2;
 	return s;
 }

 /*
  * Convert non-negative integer string representation in explicitly given radix
  * to an integer. A maximum of max_chars characters will be converted.
  *
  * Return number of characters consumed maybe or-ed with overflow bit.
  * If overflow occurs, result integer (incorrect) is still returned.
  *
  * Don't you dare use this function.
  */
 unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *p,
 				  size_t max_chars)
 {
 	unsigned long long res;
 	unsigned int rv;

 	res = 0;
 	rv = 0;
 	while (max_chars--) {
 		unsigned int c = *s;
 		unsigned int lc = c | 0x20; /* don't tolower() this line */
 		unsigned int val;

 		if ('0' <= c && c <= '9')
 			val = c - '0';
 		else if ('a' <= lc && lc <= 'f')
 			val = lc - 'a' + 10;
 		else
 			break;

 		if (val >= base)
 			break;
 		/*
 		 * Check for overflow only if we are within range of
 		 * it in the max base we support (16)
 		 */
 		if (unlikely(res & (~0ull << 60))) {
 			if (res > div_u64(ULLONG_MAX - val, base))
 				rv |= KSTRTOX_OVERFLOW;
 		}
 		res = res * base + val;
 		rv++;
 		s++;
 	}
 	*p = res;
 	return rv;
 }

 unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p)
 {
 	return _parse_integer_limit(s, base, p, INT_MAX);
 }

 static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
 {
 	unsigned long long _res;
 	unsigned int rv;

 	s = _parse_integer_fixup_radix(s, &base);
 	rv = _parse_integer(s, base, &_res);
 	if (rv & KSTRTOX_OVERFLOW)
 		return -ERANGE;
 	if (rv == 0)
 		return -EINVAL;
 	s += rv;
 	if (*s == '\n')
 		s++;
 	if (*s)
 		return -EINVAL;
 	*res = _res;
 	return 0;
 }

 /**
  * kstrtoull - convert a string to an unsigned long long
  * @s: The start of the string. The string must be null-terminated, and may also
  *  include a single newline before its terminating null. The first character
  *  may also be a plus sign, but not a minus sign.
  * @base: The number base to use. The maximum supported base is 16. If base is
  *  given as 0, then the base of the string is automatically detected with the
  *  conventional semantics - If it begins with 0x the number will be parsed as a
  *  hexadecimal (case insensitive), if it otherwise begins with 0, it will be
  *  parsed as an octal number. Otherwise it will be parsed as a decimal.
  * @res: Where to write the result of the conversion on success.
  *
  * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
  * Preferred over simple_strtoull(). Return code must be checked.
  */
 int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
 {
 	if (s[0] == '+')
 		s++;
 	return _kstrtoull(s, base, res);
 }
 EXPORT_SYMBOL(kstrtoull);

 /**
  * kstrtoll - convert a string to a long long
  * @s: The start of the string. The string must be null-terminated, and may also
  *  include a single newline before its terminating null. The first character
  *  may also be a plus sign or a minus sign.
  * @base: The number base to use. The maximum supported base is 16. If base is
  *  given as 0, then the base of the string is automatically detected with the
  *  conventional semantics - If it begins with 0x the number will be parsed as a
  *  hexadecimal (case insensitive), if it otherwise begins with 0, it will be
  *  parsed as an octal number. Otherwise it will be parsed as a decimal.
  * @res: Where to write the result of the conversion on success.
  *
  * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
  * Preferred over simple_strtoll(). Return code must be checked.
  */
 int kstrtoll(const char *s, unsigned int base, long long *res)
 {
 	unsigned long long tmp;
 	int rv;

 	if (s[0] == '-') {
 		rv = _kstrtoull(s + 1, base, &tmp);
 		if (rv < 0)
 			return rv;
 		if ((long long)-tmp > 0)
 			return -ERANGE;
 		*res = -tmp;
 	} else {
 		rv = kstrtoull(s, base, &tmp);
 		if (rv < 0)
 			return rv;
 		if ((long long)tmp < 0)
 			return -ERANGE;
 		*res = tmp;
 	}
 	return 0;
 }
 EXPORT_SYMBOL(kstrtoll);

 /* Internal, do not use. */
 int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
 {
 	unsigned long long tmp;
 	int rv;

 	rv = kstrtoull(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (unsigned long)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(_kstrtoul);

 /* Internal, do not use. */
 int _kstrtol(const char *s, unsigned int base, long *res)
 {
 	long long tmp;
 	int rv;

 	rv = kstrtoll(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (long)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(_kstrtol);

 /**
  * kstrtouint - convert a string to an unsigned int
  * @s: The start of the string. The string must be null-terminated, and may also
  *  include a single newline before its terminating null. The first character
  *  may also be a plus sign, but not a minus sign.
  * @base: The number base to use. The maximum supported base is 16. If base is
  *  given as 0, then the base of the string is automatically detected with the
  *  conventional semantics - If it begins with 0x the number will be parsed as a
  *  hexadecimal (case insensitive), if it otherwise begins with 0, it will be
  *  parsed as an octal number. Otherwise it will be parsed as a decimal.
  * @res: Where to write the result of the conversion on success.
  *
  * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
  * Preferred over simple_strtoul(). Return code must be checked.
  */
 int kstrtouint(const char *s, unsigned int base, unsigned int *res)
 {
 	unsigned long long tmp;
 	int rv;

 	rv = kstrtoull(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (unsigned int)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtouint);

 /**
  * kstrtoint - convert a string to an int
  * @s: The start of the string. The string must be null-terminated, and may also
  *  include a single newline before its terminating null. The first character
  *  may also be a plus sign or a minus sign.
  * @base: The number base to use. The maximum supported base is 16. If base is
  *  given as 0, then the base of the string is automatically detected with the
  *  conventional semantics - If it begins with 0x the number will be parsed as a
  *  hexadecimal (case insensitive), if it otherwise begins with 0, it will be
  *  parsed as an octal number. Otherwise it will be parsed as a decimal.
  * @res: Where to write the result of the conversion on success.
  *
  * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
  * Preferred over simple_strtol(). Return code must be checked.
  */
 int kstrtoint(const char *s, unsigned int base, int *res)
 {
 	long long tmp;
 	int rv;

 	rv = kstrtoll(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (int)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtoint);

 int kstrtou16(const char *s, unsigned int base, u16 *res)
 {
 	unsigned long long tmp;
 	int rv;

 	rv = kstrtoull(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (u16)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtou16);

 int kstrtos16(const char *s, unsigned int base, s16 *res)
 {
 	long long tmp;
 	int rv;

 	rv = kstrtoll(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (s16)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtos16);

 int kstrtou8(const char *s, unsigned int base, u8 *res)
 {
 	unsigned long long tmp;
 	int rv;

 	rv = kstrtoull(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (u8)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtou8);

 int kstrtos8(const char *s, unsigned int base, s8 *res)
 {
 	long long tmp;
 	int rv;

 	rv = kstrtoll(s, base, &tmp);
 	if (rv < 0)
 		return rv;
 	if (tmp != (s8)tmp)
 		return -ERANGE;
 	*res = tmp;
 	return 0;
 }
 EXPORT_SYMBOL(kstrtos8);

 /**
  * kstrtobool - convert common user inputs into boolean values
  * @s: input string
  * @res: result
  *
  * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
  * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL.  Value
  * pointed to by res is updated upon finding a match.
  */
 int kstrtobool(const char *s, bool *res)
 {
 	if (!s)
 		return -EINVAL;

 	switch (s[0]) {
 	case 'y':
 	case 'Y':
 	case '1':
 		*res = true;
 		return 0;
 	case 'n':
 	case 'N':
 	case '0':
 		*res = false;
 		return 0;
 	case 'o':
 	case 'O':
 		switch (s[1]) {
 		case 'n':
 		case 'N':
 			*res = true;
 			return 0;
 		case 'f':
 		case 'F':
 			*res = false;
 			return 0;
 		default:
 			break;
 		}
 		break;
 	default:
 		break;
 	}

 	return -EINVAL;
 }
 EXPORT_SYMBOL(kstrtobool);

 /*
  * Since "base" would be a nonsense argument, this open-codes the
  * _from_user helper instead of using the helper macro below.
  */
 int kstrtobool_from_user(const char __user *s, size_t count, bool *res)
 {
 	/* Longest string needed to differentiate, newline, terminator */
 	char buf[4];

 	count = min(count, sizeof(buf) - 1);
 	if (copy_from_user(buf, s, count))
 		return -EFAULT;
 	buf[count] = '\0';
 	return kstrtobool(buf, res);
 }
 EXPORT_SYMBOL(kstrtobool_from_user);

 #define kstrto_from_user(f, g, type)					\
 int f(const char __user *s, size_t count, unsigned int base, type *res)	\
 {									\
 	/* sign, base 2 representation, newline, terminator */		\
 	char buf[1 + sizeof(type) * 8 + 1 + 1];				\
 									\
 	count = min(count, sizeof(buf) - 1);				\
 	if (copy_from_user(buf, s, count))				\
 		return -EFAULT;						\
 	buf[count] = '\0';						\
 	return g(buf, base, res);					\
 }									\
 EXPORT_SYMBOL(f)

 kstrto_from_user(kstrtoull_from_user,	kstrtoull,	unsigned long long);
 kstrto_from_user(kstrtoll_from_user,	kstrtoll,	long long);
 kstrto_from_user(kstrtoul_from_user,	kstrtoul,	unsigned long);
 kstrto_from_user(kstrtol_from_user,	kstrtol,	long);
 kstrto_from_user(kstrtouint_from_user,	kstrtouint,	unsigned int);
 kstrto_from_user(kstrtoint_from_user,	kstrtoint,	int);
 kstrto_from_user(kstrtou16_from_user,	kstrtou16,	u16);
 kstrto_from_user(kstrtos16_from_user,	kstrtos16,	s16);
 kstrto_from_user(kstrtou8_from_user,	kstrtou8,	u8);
 kstrto_from_user(kstrtos8_from_user,	kstrtos8,	s8);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Convert integer string representation to an integer.
	* If an integer doesn't fit into specified type, -E is returned.
	*
	* Integer starts with optional sign.
	* kstrtou*() functions do not accept sign "-".
	*
	* Radix 0 means autodetection: leading "0x" implies radix 16,
	* leading "0" implies radix 8, otherwise radix is 10.
	* Autodetection hints work after optional sign, but not before.
	*
	* If -E is returned, result is not touched.
	*/
	#include <linux/ctype.h>
	#include <linux/errno.h>
	#include <linux/export.h>
	#include <linux/kstrtox.h>
	#include <linux/math64.h>
	#include <linux/types.h>
	#include <linux/uaccess.h>

	#include "kstrtox.h"

	const char _parse_integer_fixup_radix(const char s, unsigned int *base)
	{
	if (*base == 0) {
	if (s[0] == '0') {
	if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
	*base = 16;
	else
	*base = 8;
	} else
	*base = 10;
	}
	if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
	s += 2;
	return s;
	}

	/*
	* Convert non-negative integer string representation in explicitly given radix
	* to an integer. A maximum of max_chars characters will be converted.
	*
	* Return number of characters consumed maybe or-ed with overflow bit.
	* If overflow occurs, result integer (incorrect) is still returned.
	*
	* Don't you dare use this function.
	*/
	unsigned int _parse_integer_limit(const char s, unsigned int base, unsigned long long p,
	size_t max_chars)
	{
	unsigned long long res;
	unsigned int rv;

	res = 0;
	rv = 0;
	while (max_chars--) {
	unsigned int c = *s;
	unsigned int lc = c \| 0x20; /* don't tolower() this line */
	unsigned int val;

	if ('0' <= c && c <= '9')
	val = c - '0';
	else if ('a' <= lc && lc <= 'f')
	val = lc - 'a' + 10;
	else
	break;

	if (val >= base)
	break;
	/*
	* Check for overflow only if we are within range of
	* it in the max base we support (16)
	*/
	if (unlikely(res & (~0ull << 60))) {
	if (res > div_u64(ULLONG_MAX - val, base))
	rv \|= KSTRTOX_OVERFLOW;
	}
	res = res * base + val;
	rv++;
	s++;
	}
	*p = res;
	return rv;
	}

	unsigned int _parse_integer(const char s, unsigned int base, unsigned long long p)
	{
	return _parse_integer_limit(s, base, p, INT_MAX);
	}

	static int _kstrtoull(const char s, unsigned int base, unsigned long long res)
	{
	unsigned long long _res;
	unsigned int rv;

	s = _parse_integer_fixup_radix(s, &base);
	rv = _parse_integer(s, base, &_res);
	if (rv & KSTRTOX_OVERFLOW)
	return -ERANGE;
	if (rv == 0)
	return -EINVAL;
	s += rv;
	if (*s == '\n')
	s++;
	if (*s)
	return -EINVAL;
	*res = _res;
	return 0;
	}

	/**
	* kstrtoull - convert a string to an unsigned long long
	* @s: The start of the string. The string must be null-terminated, and may also
	* include a single newline before its terminating null. The first character
	* may also be a plus sign, but not a minus sign.
	* @base: The number base to use. The maximum supported base is 16. If base is
	* given as 0, then the base of the string is automatically detected with the
	* conventional semantics - If it begins with 0x the number will be parsed as a
	* hexadecimal (case insensitive), if it otherwise begins with 0, it will be
	* parsed as an octal number. Otherwise it will be parsed as a decimal.
	* @res: Where to write the result of the conversion on success.
	*
	* Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
	* Preferred over simple_strtoull(). Return code must be checked.
	*/
	int kstrtoull(const char s, unsigned int base, unsigned long long res)
	{
	if (s[0] == '+')
	s++;
	return _kstrtoull(s, base, res);
	}
	EXPORT_SYMBOL(kstrtoull);

	/**
	* kstrtoll - convert a string to a long long
	* @s: The start of the string. The string must be null-terminated, and may also
	* include a single newline before its terminating null. The first character
	* may also be a plus sign or a minus sign.
	* @base: The number base to use. The maximum supported base is 16. If base is
	* given as 0, then the base of the string is automatically detected with the
	* conventional semantics - If it begins with 0x the number will be parsed as a
	* hexadecimal (case insensitive), if it otherwise begins with 0, it will be
	* parsed as an octal number. Otherwise it will be parsed as a decimal.
	* @res: Where to write the result of the conversion on success.
	*
	* Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
	* Preferred over simple_strtoll(). Return code must be checked.
	*/
	int kstrtoll(const char s, unsigned int base, long long res)
	{
	unsigned long long tmp;
	int rv;

	if (s[0] == '-') {
	rv = _kstrtoull(s + 1, base, &tmp);
	if (rv < 0)
	return rv;
	if ((long long)-tmp > 0)
	return -ERANGE;
	*res = -tmp;
	} else {
	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
	return rv;
	if ((long long)tmp < 0)
	return -ERANGE;
	*res = tmp;
	}
	return 0;
	}
	EXPORT_SYMBOL(kstrtoll);

	/* Internal, do not use. */
	int _kstrtoul(const char s, unsigned int base, unsigned long res)
	{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (unsigned long)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(_kstrtoul);

	/* Internal, do not use. */
	int _kstrtol(const char s, unsigned int base, long res)
	{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (long)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(_kstrtol);

	/**
	* kstrtouint - convert a string to an unsigned int
	* @s: The start of the string. The string must be null-terminated, and may also
	* include a single newline before its terminating null. The first character
	* may also be a plus sign, but not a minus sign.
	* @base: The number base to use. The maximum supported base is 16. If base is
	* given as 0, then the base of the string is automatically detected with the
	* conventional semantics - If it begins with 0x the number will be parsed as a
	* hexadecimal (case insensitive), if it otherwise begins with 0, it will be
	* parsed as an octal number. Otherwise it will be parsed as a decimal.
	* @res: Where to write the result of the conversion on success.
	*
	* Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
	* Preferred over simple_strtoul(). Return code must be checked.
	*/
	int kstrtouint(const char s, unsigned int base, unsigned int res)
	{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (unsigned int)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtouint);

	/**
	* kstrtoint - convert a string to an int
	* @s: The start of the string. The string must be null-terminated, and may also
	* include a single newline before its terminating null. The first character
	* may also be a plus sign or a minus sign.
	* @base: The number base to use. The maximum supported base is 16. If base is
	* given as 0, then the base of the string is automatically detected with the
	* conventional semantics - If it begins with 0x the number will be parsed as a
	* hexadecimal (case insensitive), if it otherwise begins with 0, it will be
	* parsed as an octal number. Otherwise it will be parsed as a decimal.
	* @res: Where to write the result of the conversion on success.
	*
	* Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
	* Preferred over simple_strtol(). Return code must be checked.
	*/
	int kstrtoint(const char s, unsigned int base, int res)
	{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (int)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtoint);

	int kstrtou16(const char s, unsigned int base, u16 res)
	{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (u16)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtou16);

	int kstrtos16(const char s, unsigned int base, s16 res)
	{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (s16)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtos16);

	int kstrtou8(const char s, unsigned int base, u8 res)
	{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (u8)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtou8);

	int kstrtos8(const char s, unsigned int base, s8 res)
	{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
	return rv;
	if (tmp != (s8)tmp)
	return -ERANGE;
	*res = tmp;
	return 0;
	}
	EXPORT_SYMBOL(kstrtos8);

	/**
	* kstrtobool - convert common user inputs into boolean values
	* @s: input string
	* @res: result
	*
	* This routine returns 0 iff the first character is one of 'Yy1Nn0', or
	* [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL. Value
	* pointed to by res is updated upon finding a match.
	*/
	int kstrtobool(const char s, bool res)
	{
	if (!s)
	return -EINVAL;

	switch (s[0]) {
	case 'y':
	case 'Y':
	case '1':
	*res = true;
	return 0;
	case 'n':
	case 'N':
	case '0':
	*res = false;
	return 0;
	case 'o':
	case 'O':
	switch (s[1]) {
	case 'n':
	case 'N':
	*res = true;
	return 0;
	case 'f':
	case 'F':
	*res = false;
	return 0;
	default:
	break;
	}
	break;
	default:
	break;
	}

	return -EINVAL;
	}
	EXPORT_SYMBOL(kstrtobool);

	/*
	* Since "base" would be a nonsense argument, this open-codes the
	* _from_user helper instead of using the helper macro below.
	*/
	int kstrtobool_from_user(const char __user s, size_t count, bool res)
	{
	/* Longest string needed to differentiate, newline, terminator */
	char buf[4];

	count = min(count, sizeof(buf) - 1);
	if (copy_from_user(buf, s, count))
	return -EFAULT;
	buf[count] = '\0';
	return kstrtobool(buf, res);
	}
	EXPORT_SYMBOL(kstrtobool_from_user);

	#define kstrto_from_user(f, g, type) \
	int f(const char __user s, size_t count, unsigned int base, type res) \
	{ \
	/* sign, base 2 representation, newline, terminator */ \
	char buf[1 + sizeof(type) * 8 + 1 + 1]; \
	\
	count = min(count, sizeof(buf) - 1); \
	if (copy_from_user(buf, s, count)) \
	return -EFAULT; \
	buf[count] = '\0'; \
	return g(buf, base, res); \
	} \
	EXPORT_SYMBOL(f)

	kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
	kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
	kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
	kstrto_from_user(kstrtol_from_user, kstrtol, long);
	kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
	kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
	kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
	kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
	kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
	kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);