vsprintf.c 46.8 KB
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/*
 *  linux/lib/vsprintf.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
/*
 * Wirzenius wrote this portably, Torvalds fucked it up :-)
 */

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/*
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 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
 * - changed to provide snprintf and vsnprintf functions
 * So Feb  1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
 * - scnprintf and vscnprintf
 */

#include <stdarg.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
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#include <linux/kallsyms.h>
#include <linux/uaccess.h>
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#include <linux/ioport.h>
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#include <net/addrconf.h>
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#include <asm/page.h>		/* for PAGE_SIZE */
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#include <asm/div64.h>
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#include <asm/sections.h>	/* for dereference_function_descriptor() */
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/* Works only for digits and letters, but small and fast */
#define TOLOWER(x) ((x) | 0x20)

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static unsigned int simple_guess_base(const char *cp)
{
	if (cp[0] == '0') {
		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
			return 16;
		else
			return 8;
	} else {
		return 10;
	}
}

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/**
 * simple_strtoul - convert a string to an unsigned long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
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unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
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{
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	unsigned long result = 0;

	if (!base)
		base = simple_guess_base(cp);

	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
		cp += 2;

	while (isxdigit(*cp)) {
		unsigned int value;

		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
		if (value >= base)
			break;
		result = result * base + value;
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		cp++;
	}
	if (endp)
		*endp = (char *)cp;
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	return result;
}
EXPORT_SYMBOL(simple_strtoul);

/**
 * simple_strtol - convert a string to a signed long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
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long simple_strtol(const char *cp, char **endp, unsigned int base)
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{
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	if (*cp == '-')
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		return -simple_strtoul(cp + 1, endp, base);
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	return simple_strtoul(cp, endp, base);
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}
EXPORT_SYMBOL(simple_strtol);

/**
 * simple_strtoull - convert a string to an unsigned long long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
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unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
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{
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	unsigned long long result = 0;

	if (!base)
		base = simple_guess_base(cp);

	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
		cp += 2;

	while (isxdigit(*cp)) {
		unsigned int value;

		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
		if (value >= base)
			break;
		result = result * base + value;
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		cp++;
	}
	if (endp)
		*endp = (char *)cp;
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	return result;
}
EXPORT_SYMBOL(simple_strtoull);

/**
 * simple_strtoll - convert a string to a signed long long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
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long long simple_strtoll(const char *cp, char **endp, unsigned int base)
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{
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	if (*cp == '-')
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		return -simple_strtoull(cp + 1, endp, base);
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	return simple_strtoull(cp, endp, base);
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}

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/**
 * strict_strtoul - convert a string to an unsigned long strictly
 * @cp: The string to be converted
 * @base: The number base to use
 * @res: The converted result value
 *
 * strict_strtoul converts a string to an unsigned long only if the
 * string is really an unsigned long string, any string containing
 * any invalid char at the tail will be rejected and -EINVAL is returned,
 * only a newline char at the tail is acceptible because people generally
 * change a module parameter in the following way:
 *
 * 	echo 1024 > /sys/module/e1000/parameters/copybreak
 *
 * echo will append a newline to the tail.
 *
 * It returns 0 if conversion is successful and *res is set to the converted
 * value, otherwise it returns -EINVAL and *res is set to 0.
 *
 * simple_strtoul just ignores the successive invalid characters and
 * return the converted value of prefix part of the string.
 */
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int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
{
	char *tail;
	unsigned long val;
	size_t len;

	*res = 0;
	len = strlen(cp);
	if (len == 0)
		return -EINVAL;

	val = simple_strtoul(cp, &tail, base);
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	if (tail == cp)
		return -EINVAL;
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	if ((*tail == '\0') ||
		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
		*res = val;
		return 0;
	}

	return -EINVAL;
}
EXPORT_SYMBOL(strict_strtoul);
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/**
 * strict_strtol - convert a string to a long strictly
 * @cp: The string to be converted
 * @base: The number base to use
 * @res: The converted result value
 *
 * strict_strtol is similiar to strict_strtoul, but it allows the first
 * character of a string is '-'.
 *
 * It returns 0 if conversion is successful and *res is set to the converted
 * value, otherwise it returns -EINVAL and *res is set to 0.
 */
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int strict_strtol(const char *cp, unsigned int base, long *res)
{
	int ret;
	if (*cp == '-') {
		ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
		if (!ret)
			*res = -(*res);
	} else {
		ret = strict_strtoul(cp, base, (unsigned long *)res);
	}

	return ret;
}
EXPORT_SYMBOL(strict_strtol);
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/**
 * strict_strtoull - convert a string to an unsigned long long strictly
 * @cp: The string to be converted
 * @base: The number base to use
 * @res: The converted result value
 *
 * strict_strtoull converts a string to an unsigned long long only if the
 * string is really an unsigned long long string, any string containing
 * any invalid char at the tail will be rejected and -EINVAL is returned,
 * only a newline char at the tail is acceptible because people generally
 * change a module parameter in the following way:
 *
 * 	echo 1024 > /sys/module/e1000/parameters/copybreak
 *
 * echo will append a newline to the tail of the string.
 *
 * It returns 0 if conversion is successful and *res is set to the converted
 * value, otherwise it returns -EINVAL and *res is set to 0.
 *
 * simple_strtoull just ignores the successive invalid characters and
 * return the converted value of prefix part of the string.
 */
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int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
{
	char *tail;
	unsigned long long val;
	size_t len;

	*res = 0;
	len = strlen(cp);
	if (len == 0)
		return -EINVAL;

	val = simple_strtoull(cp, &tail, base);
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	if (tail == cp)
		return -EINVAL;
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	if ((*tail == '\0') ||
		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
		*res = val;
		return 0;
	}

	return -EINVAL;
}
EXPORT_SYMBOL(strict_strtoull);
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/**
 * strict_strtoll - convert a string to a long long strictly
 * @cp: The string to be converted
 * @base: The number base to use
 * @res: The converted result value
 *
 * strict_strtoll is similiar to strict_strtoull, but it allows the first
 * character of a string is '-'.
 *
 * It returns 0 if conversion is successful and *res is set to the converted
 * value, otherwise it returns -EINVAL and *res is set to 0.
 */
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int strict_strtoll(const char *cp, unsigned int base, long long *res)
{
	int ret;
	if (*cp == '-') {
		ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
		if (!ret)
			*res = -(*res);
	} else {
		ret = strict_strtoull(cp, base, (unsigned long long *)res);
	}
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	return ret;
}
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EXPORT_SYMBOL(strict_strtoll);

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static int skip_atoi(const char **s)
{
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	int i = 0;
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	while (isdigit(**s))
		i = i*10 + *((*s)++) - '0';
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	return i;
}

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/* Decimal conversion is by far the most typical, and is used
 * for /proc and /sys data. This directly impacts e.g. top performance
 * with many processes running. We optimize it for speed
 * using code from
 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 * (with permission from the author, Douglas W. Jones). */

/* Formats correctly any integer in [0,99999].
 * Outputs from one to five digits depending on input.
 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
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static char *put_dec_trunc(char *buf, unsigned q)
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{
	unsigned d3, d2, d1, d0;
	d1 = (q>>4) & 0xf;
	d2 = (q>>8) & 0xf;
	d3 = (q>>12);

	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
	q = (d0 * 0xcd) >> 11;
	d0 = d0 - 10*q;
	*buf++ = d0 + '0'; /* least significant digit */
	d1 = q + 9*d3 + 5*d2 + d1;
	if (d1 != 0) {
		q = (d1 * 0xcd) >> 11;
		d1 = d1 - 10*q;
		*buf++ = d1 + '0'; /* next digit */

		d2 = q + 2*d2;
		if ((d2 != 0) || (d3 != 0)) {
			q = (d2 * 0xd) >> 7;
			d2 = d2 - 10*q;
			*buf++ = d2 + '0'; /* next digit */

			d3 = q + 4*d3;
			if (d3 != 0) {
				q = (d3 * 0xcd) >> 11;
				d3 = d3 - 10*q;
				*buf++ = d3 + '0';  /* next digit */
				if (q != 0)
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					*buf++ = q + '0'; /* most sign. digit */
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			}
		}
	}
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	return buf;
}
/* Same with if's removed. Always emits five digits */
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static char *put_dec_full(char *buf, unsigned q)
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{
	/* BTW, if q is in [0,9999], 8-bit ints will be enough, */
	/* but anyway, gcc produces better code with full-sized ints */
	unsigned d3, d2, d1, d0;
	d1 = (q>>4) & 0xf;
	d2 = (q>>8) & 0xf;
	d3 = (q>>12);

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	/*
	 * Possible ways to approx. divide by 10
	 * gcc -O2 replaces multiply with shifts and adds
	 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
	 * (x * 0x67) >> 10:  1100111
	 * (x * 0x34) >> 9:    110100 - same
	 * (x * 0x1a) >> 8:     11010 - same
	 * (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
	 */
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	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
	q = (d0 * 0xcd) >> 11;
	d0 = d0 - 10*q;
	*buf++ = d0 + '0';
	d1 = q + 9*d3 + 5*d2 + d1;
		q = (d1 * 0xcd) >> 11;
		d1 = d1 - 10*q;
		*buf++ = d1 + '0';

		d2 = q + 2*d2;
			q = (d2 * 0xd) >> 7;
			d2 = d2 - 10*q;
			*buf++ = d2 + '0';

			d3 = q + 4*d3;
				q = (d3 * 0xcd) >> 11; /* - shorter code */
				/* q = (d3 * 0x67) >> 10; - would also work */
				d3 = d3 - 10*q;
				*buf++ = d3 + '0';
					*buf++ = q + '0';
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	return buf;
}
/* No inlining helps gcc to use registers better */
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static noinline char *put_dec(char *buf, unsigned long long num)
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{
	while (1) {
		unsigned rem;
		if (num < 100000)
			return put_dec_trunc(buf, num);
		rem = do_div(num, 100000);
		buf = put_dec_full(buf, rem);
	}
}

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#define ZEROPAD	1		/* pad with zero */
#define SIGN	2		/* unsigned/signed long */
#define PLUS	4		/* show plus */
#define SPACE	8		/* space if plus */
#define LEFT	16		/* left justified */
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#define SMALL	32		/* Must be 32 == 0x20 */
#define SPECIAL	64		/* 0x */
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enum format_type {
	FORMAT_TYPE_NONE, /* Just a string part */
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	FORMAT_TYPE_WIDTH,
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	FORMAT_TYPE_PRECISION,
	FORMAT_TYPE_CHAR,
	FORMAT_TYPE_STR,
	FORMAT_TYPE_PTR,
	FORMAT_TYPE_PERCENT_CHAR,
	FORMAT_TYPE_INVALID,
	FORMAT_TYPE_LONG_LONG,
	FORMAT_TYPE_ULONG,
	FORMAT_TYPE_LONG,
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	FORMAT_TYPE_UBYTE,
	FORMAT_TYPE_BYTE,
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	FORMAT_TYPE_USHORT,
	FORMAT_TYPE_SHORT,
	FORMAT_TYPE_UINT,
	FORMAT_TYPE_INT,
	FORMAT_TYPE_NRCHARS,
	FORMAT_TYPE_SIZE_T,
	FORMAT_TYPE_PTRDIFF
};

struct printf_spec {
	enum format_type	type;
	int			flags;		/* flags to number() */
	int			field_width;	/* width of output field */
	int			base;
	int			precision;	/* # of digits/chars */
	int			qualifier;
};

static char *number(char *buf, char *end, unsigned long long num,
			struct printf_spec spec)
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{
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	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */

	char tmp[66];
	char sign;
	char locase;
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	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
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	int i;

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	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
	 * produces same digits or (maybe lowercased) letters */
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	locase = (spec.flags & SMALL);
	if (spec.flags & LEFT)
		spec.flags &= ~ZEROPAD;
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	sign = 0;
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	if (spec.flags & SIGN) {
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		if ((signed long long)num < 0) {
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			sign = '-';
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			num = -(signed long long)num;
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			spec.field_width--;
		} else if (spec.flags & PLUS) {
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			sign = '+';
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			spec.field_width--;
		} else if (spec.flags & SPACE) {
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			sign = ' ';
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			spec.field_width--;
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		}
	}
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	if (need_pfx) {
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		spec.field_width--;
		if (spec.base == 16)
			spec.field_width--;
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	}
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	/* generate full string in tmp[], in reverse order */
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	i = 0;
	if (num == 0)
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		tmp[i++] = '0';
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	/* Generic code, for any base:
	else do {
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		tmp[i++] = (digits[do_div(num,base)] | locase);
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	} while (num != 0);
	*/
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	else if (spec.base != 10) { /* 8 or 16 */
		int mask = spec.base - 1;
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		int shift = 3;
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		if (spec.base == 16)
			shift = 4;
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		do {
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			tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
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			num >>= shift;
		} while (num);
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	} else { /* base 10 */
		i = put_dec(tmp, num) - tmp;
	}
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	/* printing 100 using %2d gives "100", not "00" */
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	if (i > spec.precision)
		spec.precision = i;
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	/* leading space padding */
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	spec.field_width -= spec.precision;
	if (!(spec.flags & (ZEROPAD+LEFT))) {
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		while (--spec.field_width >= 0) {
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			if (buf < end)
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				*buf = ' ';
			++buf;
		}
	}
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	/* sign */
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	if (sign) {
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		if (buf < end)
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			*buf = sign;
		++buf;
	}
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	/* "0x" / "0" prefix */
	if (need_pfx) {
		if (buf < end)
			*buf = '0';
		++buf;
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		if (spec.base == 16) {
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			if (buf < end)
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				*buf = ('X' | locase);
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			++buf;
		}
	}
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	/* zero or space padding */
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	if (!(spec.flags & LEFT)) {
		char c = (spec.flags & ZEROPAD) ? '0' : ' ';
		while (--spec.field_width >= 0) {
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			if (buf < end)
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				*buf = c;
			++buf;
		}
	}
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	/* hmm even more zero padding? */
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	while (i <= --spec.precision) {
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		if (buf < end)
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			*buf = '0';
		++buf;
	}
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	/* actual digits of result */
	while (--i >= 0) {
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		if (buf < end)
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			*buf = tmp[i];
		++buf;
	}
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	/* trailing space padding */
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	while (--spec.field_width >= 0) {
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		if (buf < end)
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			*buf = ' ';
		++buf;
	}
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	return buf;
}

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static char *string(char *buf, char *end, const char *s, struct printf_spec spec)
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{
	int len, i;

	if ((unsigned long)s < PAGE_SIZE)
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		s = "(null)";
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	len = strnlen(s, spec.precision);
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	if (!(spec.flags & LEFT)) {
		while (len < spec.field_width--) {
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			if (buf < end)
				*buf = ' ';
			++buf;
		}
	}
	for (i = 0; i < len; ++i) {
		if (buf < end)
			*buf = *s;
		++buf; ++s;
	}
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	while (len < spec.field_width--) {
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		if (buf < end)
			*buf = ' ';
		++buf;
	}
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	return buf;
}

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static char *symbol_string(char *buf, char *end, void *ptr,
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				struct printf_spec spec, char ext)
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{
	unsigned long value = (unsigned long) ptr;
#ifdef CONFIG_KALLSYMS
	char sym[KSYM_SYMBOL_LEN];
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	if (ext != 'f' && ext != 's')
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		sprint_symbol(sym, value);
	else
		kallsyms_lookup(value, NULL, NULL, NULL, sym);
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	return string(buf, end, sym, spec);
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#else
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	spec.field_width = 2 * sizeof(void *);
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	spec.flags |= SPECIAL | SMALL | ZEROPAD;
	spec.base = 16;
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	return number(buf, end, value, spec);
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#endif
}

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static char *resource_string(char *buf, char *end, struct resource *res,
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				struct printf_spec spec, const char *fmt)
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{
#ifndef IO_RSRC_PRINTK_SIZE
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#define IO_RSRC_PRINTK_SIZE	6
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#endif

#ifndef MEM_RSRC_PRINTK_SIZE
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#define MEM_RSRC_PRINTK_SIZE	10
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#endif
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	struct printf_spec hex_spec = {
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		.base = 16,
		.precision = -1,
		.flags = SPECIAL | SMALL | ZEROPAD,
	};
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	struct printf_spec dec_spec = {
		.base = 10,
		.precision = -1,
		.flags = 0,
	};
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	struct printf_spec str_spec = {
		.field_width = -1,
		.precision = 10,
		.flags = LEFT,
	};
	struct printf_spec flag_spec = {
		.base = 16,
		.precision = -1,
		.flags = SPECIAL | SMALL,
	};
640 641 642 643 644 645 646 647 648 649

	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
#define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
#define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
#define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref disabled]")
#define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];

650
	char *p = sym, *pend = sym + sizeof(sym);
651
	int size = -1, addr = 0;
652
	int decode = (fmt[0] == 'R') ? 1 : 0;
653

654
	if (res->flags & IORESOURCE_IO) {
655
		size = IO_RSRC_PRINTK_SIZE;
656 657
		addr = 1;
	} else if (res->flags & IORESOURCE_MEM) {
658
		size = MEM_RSRC_PRINTK_SIZE;
659 660
		addr = 1;
	}
661 662

	*p++ = '[';
663 664 665 666 667 668 669 670 671 672 673
	if (res->flags & IORESOURCE_IO)
		p = string(p, pend, "io  ", str_spec);
	else if (res->flags & IORESOURCE_MEM)
		p = string(p, pend, "mem ", str_spec);
	else if (res->flags & IORESOURCE_IRQ)
		p = string(p, pend, "irq ", str_spec);
	else if (res->flags & IORESOURCE_DMA)
		p = string(p, pend, "dma ", str_spec);
	else {
		p = string(p, pend, "??? ", str_spec);
		decode = 0;
674
	}
675 676 677 678 679 680
	hex_spec.field_width = size;
	p = number(p, pend, res->start, addr ? hex_spec : dec_spec);
	if (res->start != res->end) {
		*p++ = '-';
		p = number(p, pend, res->end, addr ? hex_spec : dec_spec);
	}
681
	if (decode) {
682 683 684 685 686 687
		if (res->flags & IORESOURCE_MEM_64)
			p = string(p, pend, " 64bit", str_spec);
		if (res->flags & IORESOURCE_PREFETCH)
			p = string(p, pend, " pref", str_spec);
		if (res->flags & IORESOURCE_DISABLED)
			p = string(p, pend, " disabled", str_spec);
688 689 690
	} else {
		p = string(p, pend, " flags ", str_spec);
		p = number(p, pend, res->flags, flag_spec);
691
	}
692
	*p++ = ']';
693
	*p = '\0';
694

695
	return string(buf, end, sym, spec);
696 697
}

698
static char *mac_address_string(char *buf, char *end, u8 *addr,
699
				struct printf_spec spec, const char *fmt)
700
{
701
	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
702 703 704 705 706
	char *p = mac_addr;
	int i;

	for (i = 0; i < 6; i++) {
		p = pack_hex_byte(p, addr[i]);
707
		if (fmt[0] == 'M' && i != 5)
708 709 710 711
			*p++ = ':';
	}
	*p = '\0';

712
	return string(buf, end, mac_addr, spec);
713 714
}

715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734
static char *ip4_string(char *p, const u8 *addr, bool leading_zeros)
{
	int i;

	for (i = 0; i < 4; i++) {
		char temp[3];	/* hold each IP quad in reverse order */
		int digits = put_dec_trunc(temp, addr[i]) - temp;
		if (leading_zeros) {
			if (digits < 3)
				*p++ = '0';
			if (digits < 2)
				*p++ = '0';
		}
		/* reverse the digits in the quad */
		while (digits--)
			*p++ = temp[digits];
		if (i < 3)
			*p++ = '.';
	}
	*p = '\0';
735

736 737 738
	return p;
}

739
static char *ip6_compressed_string(char *p, const char *addr)
740
{
741
	int i, j, range;
742 743 744 745
	unsigned char zerolength[8];
	int longest = 1;
	int colonpos = -1;
	u16 word;
746
	u8 hi, lo;
747
	bool needcolon = false;
748 749 750 751 752 753
	bool useIPv4;
	struct in6_addr in6;

	memcpy(&in6, addr, sizeof(struct in6_addr));

	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
754 755 756 757 758 759 760 761 762 763 764

	memset(zerolength, 0, sizeof(zerolength));

	if (useIPv4)
		range = 6;
	else
		range = 8;

	/* find position of longest 0 run */
	for (i = 0; i < range; i++) {
		for (j = i; j < range; j++) {
765
			if (in6.s6_addr16[j] != 0)
766 767 768 769 770 771 772 773 774 775
				break;
			zerolength[i]++;
		}
	}
	for (i = 0; i < range; i++) {
		if (zerolength[i] > longest) {
			longest = zerolength[i];
			colonpos = i;
		}
	}
776

777 778 779 780 781 782 783 784 785 786 787 788 789 790 791
	/* emit address */
	for (i = 0; i < range; i++) {
		if (i == colonpos) {
			if (needcolon || i == 0)
				*p++ = ':';
			*p++ = ':';
			needcolon = false;
			i += longest - 1;
			continue;
		}
		if (needcolon) {
			*p++ = ':';
			needcolon = false;
		}
		/* hex u16 without leading 0s */
792
		word = ntohs(in6.s6_addr16[i]);
793 794 795 796 797 798 799
		hi = word >> 8;
		lo = word & 0xff;
		if (hi) {
			if (hi > 0x0f)
				p = pack_hex_byte(p, hi);
			else
				*p++ = hex_asc_lo(hi);
800
			p = pack_hex_byte(p, lo);
801
		}
802
		else if (lo > 0x0f)
803 804 805 806 807 808 809 810 811
			p = pack_hex_byte(p, lo);
		else
			*p++ = hex_asc_lo(lo);
		needcolon = true;
	}

	if (useIPv4) {
		if (needcolon)
			*p++ = ':';
812
		p = ip4_string(p, &in6.s6_addr[12], false);
813 814
	}
	*p = '\0';
815

816 817 818
	return p;
}

819
static char *ip6_string(char *p, const char *addr, const char *fmt)
820 821
{
	int i;
822

823
	for (i = 0; i < 8; i++) {
824 825
		p = pack_hex_byte(p, *addr++);
		p = pack_hex_byte(p, *addr++);
826
		if (fmt[0] == 'I' && i != 7)
827 828 829
			*p++ = ':';
	}
	*p = '\0';
830

831 832 833 834 835 836 837 838 839
	return p;
}

static char *ip6_addr_string(char *buf, char *end, const u8 *addr,
			     struct printf_spec spec, const char *fmt)
{
	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];

	if (fmt[0] == 'I' && fmt[2] == 'c')
840
		ip6_compressed_string(ip6_addr, addr);
841
	else
842
		ip6_string(ip6_addr, addr, fmt);
843

844
	return string(buf, end, ip6_addr, spec);
845 846
}

847 848
static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
			     struct printf_spec spec, const char *fmt)
849
{
850
	char ip4_addr[sizeof("255.255.255.255")];
851

852
	ip4_string(ip4_addr, addr, fmt[0] == 'i');
853

854
	return string(buf, end, ip4_addr, spec);
855 856
}

857 858 859 860 861
/*
 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 * by an extra set of alphanumeric characters that are extended format
 * specifiers.
 *
862 863
 * Right now we handle:
 *
864 865
 * - 'F' For symbolic function descriptor pointers with offset
 * - 'f' For simple symbolic function names without offset
866 867
 * - 'S' For symbolic direct pointers with offset
 * - 's' For symbolic direct pointers without offset
868 869
 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
870 871
 * - 'M' For a 6-byte MAC address, it prints the address in the
 *       usual colon-separated hex notation
872 873 874 875 876 877 878 879 880
 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
 *       IPv6 omits the colons (01020304...0f)
 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
 * - 'I6c' for IPv6 addresses printed as specified by
 *       http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt
881 882 883
 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 * function pointers are really function descriptors, which contain a
 * pointer to the real address.
884
 */
885 886
static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
			struct printf_spec spec)
887
{
888
	if (!ptr)
889
		return string(buf, end, "(null)", spec);
890

891 892
	switch (*fmt) {
	case 'F':
893
	case 'f':
894
		ptr = dereference_function_descriptor(ptr);
895
	case 's':
896 897
		/* Fallthrough */
	case 'S':
898
		return symbol_string(buf, end, ptr, spec, *fmt);
899
	case 'R':
900
	case 'r':
901
		return resource_string(buf, end, ptr, spec, fmt);
902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919
	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
	case 'm':			/* Contiguous: 000102030405 */
		return mac_address_string(buf, end, ptr, spec, fmt);
	case 'I':			/* Formatted IP supported
					 * 4:	1.2.3.4
					 * 6:	0001:0203:...:0708
					 * 6c:	1::708 or 1::1.2.3.4
					 */
	case 'i':			/* Contiguous:
					 * 4:	001.002.003.004
					 * 6:   000102...0f
					 */
		switch (fmt[1]) {
		case '6':
			return ip6_addr_string(buf, end, ptr, spec, fmt);
		case '4':
			return ip4_addr_string(buf, end, ptr, spec, fmt);
		}
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956
		break;
	}
	spec.flags |= SMALL;
	if (spec.field_width == -1) {
		spec.field_width = 2*sizeof(void *);
		spec.flags |= ZEROPAD;
	}
	spec.base = 16;

	return number(buf, end, (unsigned long) ptr, spec);
}

/*
 * Helper function to decode printf style format.
 * Each call decode a token from the format and return the
 * number of characters read (or likely the delta where it wants
 * to go on the next call).
 * The decoded token is returned through the parameters
 *
 * 'h', 'l', or 'L' for integer fields
 * 'z' support added 23/7/1999 S.H.
 * 'z' changed to 'Z' --davidm 1/25/99
 * 't' added for ptrdiff_t
 *
 * @fmt: the format string
 * @type of the token returned
 * @flags: various flags such as +, -, # tokens..
 * @field_width: overwritten width
 * @base: base of the number (octal, hex, ...)
 * @precision: precision of a number
 * @qualifier: qualifier of a number (long, size_t, ...)
 */
static int format_decode(const char *fmt, struct printf_spec *spec)
{
	const char *start = fmt;

	/* we finished early by reading the field width */
957
	if (spec->type == FORMAT_TYPE_WIDTH) {
958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014
		if (spec->field_width < 0) {
			spec->field_width = -spec->field_width;
			spec->flags |= LEFT;
		}
		spec->type = FORMAT_TYPE_NONE;
		goto precision;
	}

	/* we finished early by reading the precision */
	if (spec->type == FORMAT_TYPE_PRECISION) {
		if (spec->precision < 0)
			spec->precision = 0;

		spec->type = FORMAT_TYPE_NONE;
		goto qualifier;
	}

	/* By default */
	spec->type = FORMAT_TYPE_NONE;

	for (; *fmt ; ++fmt) {
		if (*fmt == '%')
			break;
	}

	/* Return the current non-format string */
	if (fmt != start || !*fmt)
		return fmt - start;

	/* Process flags */
	spec->flags = 0;

	while (1) { /* this also skips first '%' */
		bool found = true;

		++fmt;

		switch (*fmt) {
		case '-': spec->flags |= LEFT;    break;
		case '+': spec->flags |= PLUS;    break;
		case ' ': spec->flags |= SPACE;   break;
		case '#': spec->flags |= SPECIAL; break;
		case '0': spec->flags |= ZEROPAD; break;
		default:  found = false;
		}

		if (!found)
			break;
	}

	/* get field width */
	spec->field_width = -1;

	if (isdigit(*fmt))
		spec->field_width = skip_atoi(&fmt);
	else if (*fmt == '*') {
		/* it's the next argument */
1015
		spec->type = FORMAT_TYPE_WIDTH;
1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029
		return ++fmt - start;
	}

precision:
	/* get the precision */
	spec->precision = -1;
	if (*fmt == '.') {
		++fmt;
		if (isdigit(*fmt)) {
			spec->precision = skip_atoi(&fmt);
			if (spec->precision < 0)
				spec->precision = 0;
		} else if (*fmt == '*') {
			/* it's the next argument */
1030
			spec->type = FORMAT_TYPE_PRECISION;
1031 1032 1033 1034 1035 1036 1037
			return ++fmt - start;
		}
	}

qualifier:
	/* get the conversion qualifier */
	spec->qualifier = -1;
1038 1039
	if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
	    TOLOWER(*fmt) == 'z' || *fmt == 't') {
1040 1041 1042 1043 1044 1045 1046 1047 1048
		spec->qualifier = *fmt++;
		if (unlikely(spec->qualifier == *fmt)) {
			if (spec->qualifier == 'l') {
				spec->qualifier = 'L';
				++fmt;
			} else if (spec->qualifier == 'h') {
				spec->qualifier = 'H';
				++fmt;
			}
1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089
		}
	}

	/* default base */
	spec->base = 10;
	switch (*fmt) {
	case 'c':
		spec->type = FORMAT_TYPE_CHAR;
		return ++fmt - start;

	case 's':
		spec->type = FORMAT_TYPE_STR;
		return ++fmt - start;

	case 'p':
		spec->type = FORMAT_TYPE_PTR;
		return fmt - start;
		/* skip alnum */

	case 'n':
		spec->type = FORMAT_TYPE_NRCHARS;
		return ++fmt - start;

	case '%':
		spec->type = FORMAT_TYPE_PERCENT_CHAR;
		return ++fmt - start;

	/* integer number formats - set up the flags and "break" */
	case 'o':
		spec->base = 8;
		break;

	case 'x':
		spec->flags |= SMALL;

	case 'X':
		spec->base = 16;
		break;

	case 'd':
	case 'i':
1090
		spec->flags |= SIGN;
1091
	case 'u':
1092
		break;
1093 1094 1095 1096

	default:
		spec->type = FORMAT_TYPE_INVALID;
		return fmt - start;
1097
	}
1098 1099 1100 1101

	if (spec->qualifier == 'L')
		spec->type = FORMAT_TYPE_LONG_LONG;
	else if (spec->qualifier == 'l') {
1102
		if (spec->flags & SIGN)
1103 1104 1105
			spec->type = FORMAT_TYPE_LONG;
		else
			spec->type = FORMAT_TYPE_ULONG;
1106
	} else if (TOLOWER(spec->qualifier) == 'z') {
1107 1108 1109
		spec->type = FORMAT_TYPE_SIZE_T;
	} else if (spec->qualifier == 't') {
		spec->type = FORMAT_TYPE_PTRDIFF;
1110 1111 1112 1113 1114
	} else if (spec->qualifier == 'H') {
		if (spec->flags & SIGN)
			spec->type = FORMAT_TYPE_BYTE;
		else
			spec->type = FORMAT_TYPE_UBYTE;
1115
	} else if (spec->qualifier == 'h') {
1116
		if (spec->flags & SIGN)
1117 1118 1119 1120
			spec->type = FORMAT_TYPE_SHORT;
		else
			spec->type = FORMAT_TYPE_USHORT;
	} else {
1121
		if (spec->flags & SIGN)
1122 1123 1124
			spec->type = FORMAT_TYPE_INT;
		else
			spec->type = FORMAT_TYPE_UINT;
1125
	}
1126 1127

	return ++fmt - start;
1128 1129
}

L
Linus Torvalds 已提交
1130 1131 1132 1133 1134 1135 1136
/**
 * vsnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
1137
 * This function follows C99 vsnprintf, but has some extensions:
1138 1139
 * %pS output the name of a text symbol with offset
 * %ps output the name of a text symbol without offset
1140 1141
 * %pF output the name of a function pointer with its offset
 * %pf output the name of a function pointer without its offset
1142
 * %pR output the address range in a struct resource
1143
 * %n is ignored
1144
 *
L
Linus Torvalds 已提交
1145 1146 1147 1148
 * The return value is the number of characters which would
 * be generated for the given input, excluding the trailing
 * '\0', as per ISO C99. If you want to have the exact
 * number of characters written into @buf as return value
1149
 * (not including the trailing '\0'), use vscnprintf(). If the
L
Linus Torvalds 已提交
1150 1151 1152 1153
 * return is greater than or equal to @size, the resulting
 * string is truncated.
 *
 * Call this function if you are already dealing with a va_list.
1154
 * You probably want snprintf() instead.
L
Linus Torvalds 已提交
1155 1156 1157 1158 1159
 */
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	unsigned long long num;
	char *str, *end, c;
1160 1161
	int read;
	struct printf_spec spec = {0};
L
Linus Torvalds 已提交
1162

1163 1164
	/* Reject out-of-range values early.  Large positive sizes are
	   used for unknown buffer sizes. */
M
Marcin Slusarz 已提交
1165
	if (WARN_ON_ONCE((int) size < 0))
L
Linus Torvalds 已提交
1166 1167 1168
		return 0;

	str = buf;
1169
	end = buf + size;
L
Linus Torvalds 已提交
1170

1171 1172 1173 1174
	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
L
Linus Torvalds 已提交
1175 1176
	}

1177 1178
	while (*fmt) {
		const char *old_fmt = fmt;
L
Linus Torvalds 已提交
1179

1180
		read = format_decode(fmt, &spec);
L
Linus Torvalds 已提交
1181

1182
		fmt += read;
L
Linus Torvalds 已提交
1183

1184 1185 1186 1187 1188 1189 1190
		switch (spec.type) {
		case FORMAT_TYPE_NONE: {
			int copy = read;
			if (str < end) {
				if (copy > end - str)
					copy = end - str;
				memcpy(str, old_fmt, copy);
L
Linus Torvalds 已提交
1191
			}
1192 1193
			str += read;
			break;
L
Linus Torvalds 已提交
1194 1195
		}

1196
		case FORMAT_TYPE_WIDTH:
1197 1198
			spec.field_width = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1199

1200 1201 1202
		case FORMAT_TYPE_PRECISION:
			spec.precision = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1203

1204 1205 1206
		case FORMAT_TYPE_CHAR:
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
1207
					if (str < end)
L
Linus Torvalds 已提交
1208 1209 1210
						*str = ' ';
					++str;

1211 1212 1213 1214 1215 1216 1217
				}
			}
			c = (unsigned char) va_arg(args, int);
			if (str < end)
				*str = c;
			++str;
			while (--spec.field_width > 0) {
1218
				if (str < end)
1219
					*str = ' ';
L
Linus Torvalds 已提交
1220
				++str;
1221 1222
			}
			break;
L
Linus Torvalds 已提交
1223

1224 1225 1226
		case FORMAT_TYPE_STR:
			str = string(str, end, va_arg(args, char *), spec);
			break;
L
Linus Torvalds 已提交
1227

1228 1229 1230 1231 1232 1233
		case FORMAT_TYPE_PTR:
			str = pointer(fmt+1, str, end, va_arg(args, void *),
				      spec);
			while (isalnum(*fmt))
				fmt++;
			break;
L
Linus Torvalds 已提交
1234

1235 1236 1237 1238 1239
		case FORMAT_TYPE_PERCENT_CHAR:
			if (str < end)
				*str = '%';
			++str;
			break;
L
Linus Torvalds 已提交
1240

1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252
		case FORMAT_TYPE_INVALID:
			if (str < end)
				*str = '%';
			++str;
			break;

		case FORMAT_TYPE_NRCHARS: {
			int qualifier = spec.qualifier;

			if (qualifier == 'l') {
				long *ip = va_arg(args, long *);
				*ip = (str - buf);
1253
			} else if (TOLOWER(qualifier) == 'z') {
1254 1255 1256 1257 1258 1259 1260
				size_t *ip = va_arg(args, size_t *);
				*ip = (str - buf);
			} else {
				int *ip = va_arg(args, int *);
				*ip = (str - buf);
			}
			break;
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		}
1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279

		default:
			switch (spec.type) {
			case FORMAT_TYPE_LONG_LONG:
				num = va_arg(args, long long);
				break;
			case FORMAT_TYPE_ULONG:
				num = va_arg(args, unsigned long);
				break;
			case FORMAT_TYPE_LONG:
				num = va_arg(args, long);
				break;
			case FORMAT_TYPE_SIZE_T:
				num = va_arg(args, size_t);
				break;
			case FORMAT_TYPE_PTRDIFF:
				num = va_arg(args, ptrdiff_t);
				break;
1280 1281 1282 1283 1284 1285
			case FORMAT_TYPE_UBYTE:
				num = (unsigned char) va_arg(args, int);
				break;
			case FORMAT_TYPE_BYTE:
				num = (signed char) va_arg(args, int);
				break;
1286 1287 1288 1289 1290 1291
			case FORMAT_TYPE_USHORT:
				num = (unsigned short) va_arg(args, int);
				break;
			case FORMAT_TYPE_SHORT:
				num = (short) va_arg(args, int);
				break;
1292 1293
			case FORMAT_TYPE_INT:
				num = (int) va_arg(args, int);
1294 1295 1296 1297 1298 1299
				break;
			default:
				num = va_arg(args, unsigned int);
			}

			str = number(str, end, num, spec);
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		}
	}
1302

1303 1304 1305 1306
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
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			end[-1] = '\0';
1308
	}
1309

1310
	/* the trailing null byte doesn't count towards the total */
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	return str-buf;
1312

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}
EXPORT_SYMBOL(vsnprintf);

/**
 * vscnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The return value is the number of characters which have been written into
 * the @buf not including the trailing '\0'. If @size is <= 0 the function
 * returns 0.
 *
 * Call this function if you are already dealing with a va_list.
1328
 * You probably want scnprintf() instead.
1329 1330
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	int i;

1336 1337
	i = vsnprintf(buf, size, fmt, args);

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	return (i >= size) ? (size - 1) : i;
}
EXPORT_SYMBOL(vscnprintf);

/**
 * snprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The return value is the number of characters which would be
 * generated for the given input, excluding the trailing null,
 * as per ISO C99.  If the return is greater than or equal to
 * @size, the resulting string is truncated.
1353 1354
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
1356
int snprintf(char *buf, size_t size, const char *fmt, ...)
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{
	va_list args;
	int i;

	va_start(args, fmt);
1362
	i = vsnprintf(buf, size, fmt, args);
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	va_end(args);
1364

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	return i;
}
EXPORT_SYMBOL(snprintf);

/**
 * scnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The return value is the number of characters written into @buf not including
1377
 * the trailing '\0'. If @size is <= 0 the function returns 0.
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 */

1380
int scnprintf(char *buf, size_t size, const char *fmt, ...)
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{
	va_list args;
	int i;

	va_start(args, fmt);
	i = vsnprintf(buf, size, fmt, args);
	va_end(args);
1388

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	return (i >= size) ? (size - 1) : i;
}
EXPORT_SYMBOL(scnprintf);

/**
 * vsprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The function returns the number of characters written
1400
 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
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 * buffer overflows.
 *
 * Call this function if you are already dealing with a va_list.
1404
 * You probably want sprintf() instead.
1405 1406
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
int vsprintf(char *buf, const char *fmt, va_list args)
{
	return vsnprintf(buf, INT_MAX, fmt, args);
}
EXPORT_SYMBOL(vsprintf);

/**
 * sprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The function returns the number of characters written
1421
 * into @buf. Use snprintf() or scnprintf() in order to avoid
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 * buffer overflows.
1423 1424
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
1426
int sprintf(char *buf, const char *fmt, ...)
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{
	va_list args;
	int i;

	va_start(args, fmt);
1432
	i = vsnprintf(buf, INT_MAX, fmt, args);
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	va_end(args);
1434

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	return i;
}
EXPORT_SYMBOL(sprintf);

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#ifdef CONFIG_BINARY_PRINTF
/*
 * bprintf service:
 * vbin_printf() - VA arguments to binary data
 * bstr_printf() - Binary data to text string
 */

/**
 * vbin_printf - Parse a format string and place args' binary value in a buffer
 * @bin_buf: The buffer to place args' binary value
 * @size: The size of the buffer(by words(32bits), not characters)
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The format follows C99 vsnprintf, except %n is ignored, and its argument
 * is skiped.
 *
 * The return value is the number of words(32bits) which would be generated for
 * the given input.
 *
 * NOTE:
 * If the return value is greater than @size, the resulting bin_buf is NOT
 * valid for bstr_printf().
 */
int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
{
1465
	struct printf_spec spec = {0};
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	char *str, *end;
1467
	int read;
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	str = (char *)bin_buf;
	end = (char *)(bin_buf + size);

#define save_arg(type)							\
do {									\
	if (sizeof(type) == 8) {					\
		unsigned long long value;				\
		str = PTR_ALIGN(str, sizeof(u32));			\
		value = va_arg(args, unsigned long long);		\
		if (str + sizeof(type) <= end) {			\
			*(u32 *)str = *(u32 *)&value;			\
			*(u32 *)(str + 4) = *((u32 *)&value + 1);	\
		}							\
	} else {							\
		unsigned long value;					\
		str = PTR_ALIGN(str, sizeof(type));			\
		value = va_arg(args, int);				\
		if (str + sizeof(type) <= end)				\
			*(typeof(type) *)str = (type)value;		\
	}								\
	str += sizeof(type);						\
} while (0)

1492 1493
	while (*fmt) {
		read = format_decode(fmt, &spec);
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1495
		fmt += read;
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1497 1498 1499 1500
		switch (spec.type) {
		case FORMAT_TYPE_NONE:
			break;

1501
		case FORMAT_TYPE_WIDTH:
1502 1503 1504 1505 1506
		case FORMAT_TYPE_PRECISION:
			save_arg(int);
			break;

		case FORMAT_TYPE_CHAR:
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			save_arg(char);
1508 1509 1510
			break;

		case FORMAT_TYPE_STR: {
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			const char *save_str = va_arg(args, char *);
			size_t len;
1513

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			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
					|| (unsigned long)save_str < PAGE_SIZE)
1516
				save_str = "(null)";
1517 1518 1519 1520
			len = strlen(save_str) + 1;
			if (str + len < end)
				memcpy(str, save_str, len);
			str += len;
1521
			break;
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1522
		}
1523 1524

		case FORMAT_TYPE_PTR:
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1525 1526
			save_arg(void *);
			/* skip all alphanumeric pointer suffixes */
1527
			while (isalnum(*fmt))
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				fmt++;
1529 1530 1531 1532 1533 1534 1535 1536 1537
			break;

		case FORMAT_TYPE_PERCENT_CHAR:
			break;

		case FORMAT_TYPE_INVALID:
			break;

		case FORMAT_TYPE_NRCHARS: {
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1538
			/* skip %n 's argument */
1539
			int qualifier = spec.qualifier;
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1540 1541 1542
			void *skip_arg;
			if (qualifier == 'l')
				skip_arg = va_arg(args, long *);
1543
			else if (TOLOWER(qualifier) == 'z')
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1544 1545 1546
				skip_arg = va_arg(args, size_t *);
			else
				skip_arg = va_arg(args, int *);
1547
			break;
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		}
1549 1550 1551 1552 1553

		default:
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
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				save_arg(long long);
1555 1556 1557
				break;
			case FORMAT_TYPE_ULONG:
			case FORMAT_TYPE_LONG:
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1558
				save_arg(unsigned long);
1559 1560
				break;
			case FORMAT_TYPE_SIZE_T:
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1561
				save_arg(size_t);
1562 1563
				break;
			case FORMAT_TYPE_PTRDIFF:
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				save_arg(ptrdiff_t);
1565
				break;
1566 1567 1568 1569
			case FORMAT_TYPE_UBYTE:
			case FORMAT_TYPE_BYTE:
				save_arg(char);
				break;
1570 1571
			case FORMAT_TYPE_USHORT:
			case FORMAT_TYPE_SHORT:
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1572
				save_arg(short);
1573 1574
				break;
			default:
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1575
				save_arg(int);
1576
			}
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1577 1578
		}
	}
1579

1580
	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1581
#undef save_arg
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}
EXPORT_SYMBOL_GPL(vbin_printf);

/**
 * bstr_printf - Format a string from binary arguments and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @bin_buf: Binary arguments for the format string
 *
 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
 * a binary buffer that generated by vbin_printf.
 *
 * The format follows C99 vsnprintf, but has some extensions:
1597
 *  see vsnprintf comment for details.
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 *
 * The return value is the number of characters which would
 * be generated for the given input, excluding the trailing
 * '\0', as per ISO C99. If you want to have the exact
 * number of characters written into @buf as return value
 * (not including the trailing '\0'), use vscnprintf(). If the
 * return is greater than or equal to @size, the resulting
 * string is truncated.
 */
int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
{
	unsigned long long num;
	char *str, *end, c;
	const char *args = (const char *)bin_buf;
1612
	struct printf_spec spec = {0};
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1613

M
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1614
	if (WARN_ON_ONCE((int) size < 0))
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1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640
		return 0;

	str = buf;
	end = buf + size;

#define get_arg(type)							\
({									\
	typeof(type) value;						\
	if (sizeof(type) == 8) {					\
		args = PTR_ALIGN(args, sizeof(u32));			\
		*(u32 *)&value = *(u32 *)args;				\
		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
	} else {							\
		args = PTR_ALIGN(args, sizeof(type));			\
		value = *(typeof(type) *)args;				\
	}								\
	args += sizeof(type);						\
	value;								\
})

	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
	}

1641 1642 1643
	while (*fmt) {
		int read;
		const char *old_fmt = fmt;
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1644

1645
		read = format_decode(fmt, &spec);
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1646

1647
		fmt += read;
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1648

1649 1650 1651 1652 1653 1654 1655
		switch (spec.type) {
		case FORMAT_TYPE_NONE: {
			int copy = read;
			if (str < end) {
				if (copy > end - str)
					copy = end - str;
				memcpy(str, old_fmt, copy);
L
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1656
			}
1657 1658
			str += read;
			break;
L
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1659 1660
		}

1661
		case FORMAT_TYPE_WIDTH:
1662 1663
			spec.field_width = get_arg(int);
			break;
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1664

1665 1666 1667
		case FORMAT_TYPE_PRECISION:
			spec.precision = get_arg(int);
			break;
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1669 1670 1671
		case FORMAT_TYPE_CHAR:
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
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					if (str < end)
						*str = ' ';
					++str;
				}
			}
			c = (unsigned char) get_arg(char);
			if (str < end)
				*str = c;
			++str;
1681
			while (--spec.field_width > 0) {
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				if (str < end)
					*str = ' ';
				++str;
			}
1686
			break;
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1688
		case FORMAT_TYPE_STR: {
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1689 1690 1691
			const char *str_arg = args;
			size_t len = strlen(str_arg);
			args += len + 1;
1692 1693
			str = string(str, end, (char *)str_arg, spec);
			break;
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1694 1695
		}

1696 1697 1698
		case FORMAT_TYPE_PTR:
			str = pointer(fmt+1, str, end, get_arg(void *), spec);
			while (isalnum(*fmt))
L
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1699
				fmt++;
1700
			break;
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1701

1702
		case FORMAT_TYPE_PERCENT_CHAR:
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			if (str < end)
				*str = '%';
			++str;
			break;

1708
		case FORMAT_TYPE_INVALID:
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			if (str < end)
				*str = '%';
			++str;
1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735
			break;

		case FORMAT_TYPE_NRCHARS:
			/* skip */
			break;

		default:
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
				num = get_arg(long long);
				break;
			case FORMAT_TYPE_ULONG:
				num = get_arg(unsigned long);
				break;
			case FORMAT_TYPE_LONG:
				num = get_arg(unsigned long);
				break;
			case FORMAT_TYPE_SIZE_T:
				num = get_arg(size_t);
				break;
			case FORMAT_TYPE_PTRDIFF:
				num = get_arg(ptrdiff_t);
				break;
1736 1737 1738 1739 1740 1741
			case FORMAT_TYPE_UBYTE:
				num = get_arg(unsigned char);
				break;
			case FORMAT_TYPE_BYTE:
				num = get_arg(signed char);
				break;
1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755
			case FORMAT_TYPE_USHORT:
				num = get_arg(unsigned short);
				break;
			case FORMAT_TYPE_SHORT:
				num = get_arg(short);
				break;
			case FORMAT_TYPE_UINT:
				num = get_arg(unsigned int);
				break;
			default:
				num = get_arg(int);
			}

			str = number(str, end, num, spec);
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1756 1757
		}
	}
1758

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	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
			end[-1] = '\0';
	}
1765

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#undef get_arg

	/* the trailing null byte doesn't count towards the total */
	return str - buf;
}
EXPORT_SYMBOL_GPL(bstr_printf);

/**
 * bprintf - Parse a format string and place args' binary value in a buffer
 * @bin_buf: The buffer to place args' binary value
 * @size: The size of the buffer(by words(32bits), not characters)
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The function returns the number of words(u32) written
 * into @bin_buf.
 */
int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
{
	va_list args;
	int ret;

	va_start(args, fmt);
	ret = vbin_printf(bin_buf, size, fmt, args);
	va_end(args);
1791

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	return ret;
}
EXPORT_SYMBOL_GPL(bprintf);

#endif /* CONFIG_BINARY_PRINTF */

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/**
 * vsscanf - Unformat a buffer into a list of arguments
 * @buf:	input buffer
 * @fmt:	format of buffer
 * @args:	arguments
 */
1804
int vsscanf(const char *buf, const char *fmt, va_list args)
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1805 1806 1807 1808 1809
{
	const char *str = buf;
	char *next;
	char digit;
	int num = 0;
1810
	int qualifier, base, field_width;
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1811 1812
	int is_sign = 0;

1813
	while (*fmt && *str) {
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1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834
		/* skip any white space in format */
		/* white space in format matchs any amount of
		 * white space, including none, in the input.
		 */
		if (isspace(*fmt)) {
			while (isspace(*fmt))
				++fmt;
			while (isspace(*str))
				++str;
		}

		/* anything that is not a conversion must match exactly */
		if (*fmt != '%' && *fmt) {
			if (*fmt++ != *str++)
				break;
			continue;
		}

		if (!*fmt)
			break;
		++fmt;
1835

L
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1836 1837 1838 1839
		/* skip this conversion.
		 * advance both strings to next white space
		 */
		if (*fmt == '*') {
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			while (!isspace(*fmt) && *fmt != '%' && *fmt)
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				fmt++;
			while (!isspace(*str) && *str)
				str++;
			continue;
		}

		/* get field width */
		field_width = -1;
		if (isdigit(*fmt))
			field_width = skip_atoi(&fmt);

		/* get conversion qualifier */
		qualifier = -1;
1854 1855
		if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
		    TOLOWER(*fmt) == 'z') {
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			qualifier = *fmt++;
			if (unlikely(qualifier == *fmt)) {
				if (qualifier == 'h') {
					qualifier = 'H';
					fmt++;
				} else if (qualifier == 'l') {
					qualifier = 'L';
					fmt++;
				}
			}
		}
		base = 10;
		is_sign = 0;

		if (!*fmt || !*str)
			break;

1873
		switch (*fmt++) {
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		case 'c':
		{
1876
			char *s = (char *)va_arg(args, char*);
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			if (field_width == -1)
				field_width = 1;
			do {
				*s++ = *str++;
			} while (--field_width > 0 && *str);
			num++;
		}
		continue;
		case 's':
		{
1887 1888
			char *s = (char *)va_arg(args, char *);
			if (field_width == -1)
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				field_width = INT_MAX;
			/* first, skip leading white space in buffer */
			while (isspace(*str))
				str++;

			/* now copy until next white space */
1895
			while (*str && !isspace(*str) && field_width--)
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				*s++ = *str++;
			*s = '\0';
			num++;
		}
		continue;
		case 'n':
			/* return number of characters read so far */
		{
1904
			int *i = (int *)va_arg(args, int*);
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			*i = str - buf;
		}
		continue;
		case 'o':
			base = 8;
			break;
		case 'x':
		case 'X':
			base = 16;
			break;
		case 'i':
1916
			base = 0;
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		case 'd':
			is_sign = 1;
		case 'u':
			break;
		case '%':
			/* looking for '%' in str */
1923
			if (*str++ != '%')
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				return num;
			continue;
		default:
			/* invalid format; stop here */
			return num;
		}

		/* have some sort of integer conversion.
		 * first, skip white space in buffer.
		 */
		while (isspace(*str))
			str++;

		digit = *str;
		if (is_sign && digit == '-')
			digit = *(str + 1);

		if (!digit
1942 1943 1944 1945 1946
		    || (base == 16 && !isxdigit(digit))
		    || (base == 10 && !isdigit(digit))
		    || (base == 8 && (!isdigit(digit) || digit > '7'))
		    || (base == 0 && !isdigit(digit)))
			break;
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1948
		switch (qualifier) {
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		case 'H':	/* that's 'hh' in format */
			if (is_sign) {
1951 1952
				signed char *s = (signed char *)va_arg(args, signed char *);
				*s = (signed char)simple_strtol(str, &next, base);
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			} else {
1954 1955
				unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
				*s = (unsigned char)simple_strtoul(str, &next, base);
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			}
			break;
		case 'h':
			if (is_sign) {
1960 1961
				short *s = (short *)va_arg(args, short *);
				*s = (short)simple_strtol(str, &next, base);
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			} else {
1963 1964
				unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
				*s = (unsigned short)simple_strtoul(str, &next, base);
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			}
			break;
		case 'l':
			if (is_sign) {
1969 1970
				long *l = (long *)va_arg(args, long *);
				*l = simple_strtol(str, &next, base);
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			} else {
1972 1973
				unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
				*l = simple_strtoul(str, &next, base);
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			}
			break;
		case 'L':
			if (is_sign) {
1978 1979
				long long *l = (long long *)va_arg(args, long long *);
				*l = simple_strtoll(str, &next, base);
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			} else {
1981 1982
				unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
				*l = simple_strtoull(str, &next, base);
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			}
			break;
		case 'Z':
		case 'z':
		{
1988 1989
			size_t *s = (size_t *)va_arg(args, size_t *);
			*s = (size_t)simple_strtoul(str, &next, base);
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		}
		break;
		default:
			if (is_sign) {
1994 1995
				int *i = (int *)va_arg(args, int *);
				*i = (int)simple_strtol(str, &next, base);
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			} else {
1997 1998
				unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
				*i = (unsigned int)simple_strtoul(str, &next, base);
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			}
			break;
		}
		num++;

		if (!next)
			break;
		str = next;
	}
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

	/*
	 * Now we've come all the way through so either the input string or the
	 * format ended. In the former case, there can be a %n at the current
	 * position in the format that needs to be filled.
	 */
	if (*fmt == '%' && *(fmt + 1) == 'n') {
		int *p = (int *)va_arg(args, int *);
		*p = str - buf;
	}

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	return num;
}
EXPORT_SYMBOL(vsscanf);

/**
 * sscanf - Unformat a buffer into a list of arguments
 * @buf:	input buffer
 * @fmt:	formatting of buffer
 * @...:	resulting arguments
 */
2029
int sscanf(const char *buf, const char *fmt, ...)
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{
	va_list args;
	int i;

2034 2035
	va_start(args, fmt);
	i = vsscanf(buf, fmt, args);
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	va_end(args);
2037

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	return i;
}
EXPORT_SYMBOL(sscanf);