vsprintf.c 46.9 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 :-)
 */

/* 
 * 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++;
	}
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	if (endp)
		*endp = (char *)cp;
	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 == '-')
		return -simple_strtoul(cp + 1, endp, base);
	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++;
	}
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	if (endp)
		*endp = (char *)cp;
	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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{
	if(*cp=='-')
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		return -simple_strtoull(cp + 1, endp, base);
	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)
{
	int i=0;

	while (isdigit(**s))
		i = i*10 + *((*s)++) - '0';
	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. */
static char* put_dec_trunc(char *buf, unsigned q)
{
	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)
					*buf++ = q + '0';  /* most sign. digit */
			}
		}
	}
	return buf;
}
/* Same with if's removed. Always emits five digits */
static char* put_dec_full(char *buf, unsigned q)
{
	/* 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);

	/* 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)

	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';
	return buf;
}
/* No inlining helps gcc to use registers better */
static noinline char* put_dec(char *buf, unsigned long long num)
{
	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) {
			sign = '-';
			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))) {
		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;
	}
	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;
	}
	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 *);
	spec.flags |= SPECIAL | SMALL | ZEROPAD;
	spec.base = 16;
	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,
	};
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	/* 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)];

637
	char *p = sym, *pend = sym + sizeof(sym);
638
	int size = -1, addr = 0;
639
	int decode = (fmt[0] == 'R') ? 1 : 0;
640

641
	if (res->flags & IORESOURCE_IO) {
642
		size = IO_RSRC_PRINTK_SIZE;
643 644
		addr = 1;
	} else if (res->flags & IORESOURCE_MEM) {
645
		size = MEM_RSRC_PRINTK_SIZE;
646 647
		addr = 1;
	}
648 649

	*p++ = '[';
650 651 652 653 654 655 656 657 658 659 660
	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;
661
	}
662 663 664 665 666 667
	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);
	}
668
	if (decode) {
669 670 671 672 673 674
		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);
675 676 677
	} else {
		p = string(p, pend, " flags ", str_spec);
		p = number(p, pend, res->flags, flag_spec);
678
	}
679
	*p++ = ']';
680
	*p = '\0';
681

682
	return string(buf, end, sym, spec);
683 684
}

685
static char *mac_address_string(char *buf, char *end, u8 *addr,
686
				struct printf_spec spec, const char *fmt)
687
{
688
	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
689 690 691 692 693
	char *p = mac_addr;
	int i;

	for (i = 0; i < 6; i++) {
		p = pack_hex_byte(p, addr[i]);
694
		if (fmt[0] == 'M' && i != 5)
695 696 697 698
			*p++ = ':';
	}
	*p = '\0';

699
	return string(buf, end, mac_addr, spec);
700 701
}

702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725
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';
	return p;
}

726
static char *ip6_compressed_string(char *p, const char *addr)
727 728
{
	int i;
729 730 731 732 733 734 735 736 737
	int j;
	int range;
	unsigned char zerolength[8];
	int longest = 1;
	int colonpos = -1;
	u16 word;
	u8 hi;
	u8 lo;
	bool needcolon = false;
738 739 740 741 742 743
	bool useIPv4;
	struct in6_addr in6;

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

	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
744 745 746 747 748 749 750 751 752 753 754

	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++) {
755
			if (in6.s6_addr16[j] != 0)
756 757 758 759 760 761 762 763 764 765
				break;
			zerolength[i]++;
		}
	}
	for (i = 0; i < range; i++) {
		if (zerolength[i] > longest) {
			longest = zerolength[i];
			colonpos = i;
		}
	}
766

767 768 769 770 771 772 773 774 775 776 777 778 779 780 781
	/* 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 */
782
		word = ntohs(in6.s6_addr16[i]);
783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
		hi = word >> 8;
		lo = word & 0xff;
		if (hi) {
			if (hi > 0x0f)
				p = pack_hex_byte(p, hi);
			else
				*p++ = hex_asc_lo(hi);
		}
		if (hi || lo > 0x0f)
			p = pack_hex_byte(p, lo);
		else
			*p++ = hex_asc_lo(lo);
		needcolon = true;
	}

	if (useIPv4) {
		if (needcolon)
			*p++ = ':';
801
		p = ip4_string(p, &in6.s6_addr[12], false);
802 803 804 805 806 807
	}

	*p = '\0';
	return p;
}

808
static char *ip6_string(char *p, const char *addr, const char *fmt)
809 810
{
	int i;
811
	for (i = 0; i < 8; i++) {
812 813
		p = pack_hex_byte(p, *addr++);
		p = pack_hex_byte(p, *addr++);
814
		if (fmt[0] == 'I' && i != 7)
815 816
			*p++ = ':';
	}
817

818
	*p = '\0';
819 820 821 822 823 824 825 826 827
	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')
828
		ip6_compressed_string(ip6_addr, addr);
829
	else
830
		ip6_string(ip6_addr, addr, fmt);
831

832
	return string(buf, end, ip6_addr, spec);
833 834
}

835 836
static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
			     struct printf_spec spec, const char *fmt)
837
{
838
	char ip4_addr[sizeof("255.255.255.255")];
839

840
	ip4_string(ip4_addr, addr, fmt[0] == 'i');
841

842
	return string(buf, end, ip4_addr, spec);
843 844
}

845 846 847 848 849
/*
 * 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.
 *
850 851
 * Right now we handle:
 *
852 853
 * - 'F' For symbolic function descriptor pointers with offset
 * - 'f' For simple symbolic function names without offset
854 855
 * - 'S' For symbolic direct pointers with offset
 * - 's' For symbolic direct pointers without offset
856 857
 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
858 859
 * - 'M' For a 6-byte MAC address, it prints the address in the
 *       usual colon-separated hex notation
860 861 862 863 864 865 866 867 868
 * - '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
869 870 871
 * 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.
872
 */
873 874
static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
			struct printf_spec spec)
875
{
876
	if (!ptr)
877
		return string(buf, end, "(null)", spec);
878

879 880
	switch (*fmt) {
	case 'F':
881
	case 'f':
882
		ptr = dereference_function_descriptor(ptr);
883
	case 's':
884 885
		/* Fallthrough */
	case 'S':
886
		return symbol_string(buf, end, ptr, spec, *fmt);
887
	case 'R':
888
	case 'r':
889
		return resource_string(buf, end, ptr, spec, fmt);
890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907
	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);
		}
908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944
		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 */
945
	if (spec->type == FORMAT_TYPE_WIDTH) {
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002
		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 */
1003
		spec->type = FORMAT_TYPE_WIDTH;
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
		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 */
1018
			spec->type = FORMAT_TYPE_PRECISION;
1019 1020 1021 1022 1023 1024 1025 1026 1027
			return ++fmt - start;
		}
	}

qualifier:
	/* get the conversion qualifier */
	spec->qualifier = -1;
	if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
	    *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
1028 1029 1030 1031 1032 1033 1034 1035 1036
		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;
			}
1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 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
		}
	}

	/* 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':
1078
		spec->flags |= SIGN;
1079
	case 'u':
1080
		break;
1081 1082 1083 1084

	default:
		spec->type = FORMAT_TYPE_INVALID;
		return fmt - start;
1085
	}
1086 1087 1088 1089

	if (spec->qualifier == 'L')
		spec->type = FORMAT_TYPE_LONG_LONG;
	else if (spec->qualifier == 'l') {
1090
		if (spec->flags & SIGN)
1091 1092 1093 1094 1095 1096 1097
			spec->type = FORMAT_TYPE_LONG;
		else
			spec->type = FORMAT_TYPE_ULONG;
	} else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
		spec->type = FORMAT_TYPE_SIZE_T;
	} else if (spec->qualifier == 't') {
		spec->type = FORMAT_TYPE_PTRDIFF;
1098 1099 1100 1101 1102
	} else if (spec->qualifier == 'H') {
		if (spec->flags & SIGN)
			spec->type = FORMAT_TYPE_BYTE;
		else
			spec->type = FORMAT_TYPE_UBYTE;
1103
	} else if (spec->qualifier == 'h') {
1104
		if (spec->flags & SIGN)
1105 1106 1107 1108
			spec->type = FORMAT_TYPE_SHORT;
		else
			spec->type = FORMAT_TYPE_USHORT;
	} else {
1109
		if (spec->flags & SIGN)
1110 1111 1112
			spec->type = FORMAT_TYPE_INT;
		else
			spec->type = FORMAT_TYPE_UINT;
1113
	}
1114 1115

	return ++fmt - start;
1116 1117
}

L
Linus Torvalds 已提交
1118 1119 1120 1121 1122 1123 1124
/**
 * 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
 *
1125
 * This function follows C99 vsnprintf, but has some extensions:
1126 1127
 * %pS output the name of a text symbol with offset
 * %ps output the name of a text symbol without offset
1128 1129
 * %pF output the name of a function pointer with its offset
 * %pf output the name of a function pointer without its offset
1130
 * %pR output the address range in a struct resource
1131
 * %n is ignored
1132
 *
L
Linus Torvalds 已提交
1133 1134 1135 1136
 * 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
1137
 * (not including the trailing '\0'), use vscnprintf(). If the
L
Linus Torvalds 已提交
1138 1139 1140 1141
 * 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.
1142
 * You probably want snprintf() instead.
L
Linus Torvalds 已提交
1143 1144 1145 1146 1147
 */
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	unsigned long long num;
	char *str, *end, c;
1148 1149
	int read;
	struct printf_spec spec = {0};
L
Linus Torvalds 已提交
1150

1151 1152
	/* Reject out-of-range values early.  Large positive sizes are
	   used for unknown buffer sizes. */
M
Marcin Slusarz 已提交
1153
	if (WARN_ON_ONCE((int) size < 0))
L
Linus Torvalds 已提交
1154 1155 1156
		return 0;

	str = buf;
1157
	end = buf + size;
L
Linus Torvalds 已提交
1158

1159 1160 1161 1162
	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
L
Linus Torvalds 已提交
1163 1164
	}

1165 1166
	while (*fmt) {
		const char *old_fmt = fmt;
L
Linus Torvalds 已提交
1167

1168
		read = format_decode(fmt, &spec);
L
Linus Torvalds 已提交
1169

1170
		fmt += read;
L
Linus Torvalds 已提交
1171

1172 1173 1174 1175 1176 1177 1178
		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
1179
			}
1180 1181
			str += read;
			break;
L
Linus Torvalds 已提交
1182 1183
		}

1184
		case FORMAT_TYPE_WIDTH:
1185 1186
			spec.field_width = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1187

1188 1189 1190
		case FORMAT_TYPE_PRECISION:
			spec.precision = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1191

1192 1193 1194
		case FORMAT_TYPE_CHAR:
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
1195
					if (str < end)
L
Linus Torvalds 已提交
1196 1197 1198
						*str = ' ';
					++str;

1199 1200 1201 1202 1203 1204 1205
				}
			}
			c = (unsigned char) va_arg(args, int);
			if (str < end)
				*str = c;
			++str;
			while (--spec.field_width > 0) {
1206
				if (str < end)
1207
					*str = ' ';
L
Linus Torvalds 已提交
1208
				++str;
1209 1210
			}
			break;
L
Linus Torvalds 已提交
1211

1212 1213 1214
		case FORMAT_TYPE_STR:
			str = string(str, end, va_arg(args, char *), spec);
			break;
L
Linus Torvalds 已提交
1215

1216 1217 1218 1219 1220 1221
		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
1222

1223 1224 1225 1226 1227
		case FORMAT_TYPE_PERCENT_CHAR:
			if (str < end)
				*str = '%';
			++str;
			break;
L
Linus Torvalds 已提交
1228

1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
		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);
			} else if (qualifier == 'Z' ||
					qualifier == 'z') {
				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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		}
1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268

		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;
1269 1270 1271 1272 1273 1274
			case FORMAT_TYPE_UBYTE:
				num = (unsigned char) va_arg(args, int);
				break;
			case FORMAT_TYPE_BYTE:
				num = (signed char) va_arg(args, int);
				break;
1275 1276 1277 1278 1279 1280
			case FORMAT_TYPE_USHORT:
				num = (unsigned short) va_arg(args, int);
				break;
			case FORMAT_TYPE_SHORT:
				num = (short) va_arg(args, int);
				break;
1281 1282
			case FORMAT_TYPE_INT:
				num = (int) va_arg(args, int);
1283 1284 1285 1286 1287 1288
				break;
			default:
				num = va_arg(args, unsigned int);
			}

			str = number(str, end, num, spec);
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		}
	}
1291

1292 1293 1294 1295
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
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			end[-1] = '\0';
1297
	}
1298

1299
	/* the trailing null byte doesn't count towards the total */
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	return str-buf;
1301

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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.
1317
 * You probably want scnprintf() instead.
1318 1319
 *
 * 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;

	i=vsnprintf(buf,size,fmt,args);
	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.
1341 1342
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
int snprintf(char * buf, size_t size, const char *fmt, ...)
{
	va_list args;
	int i;

	va_start(args, fmt);
	i=vsnprintf(buf,size,fmt,args);
	va_end(args);
	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
1364
 * the trailing '\0'. If @size is <= 0 the function returns 0.
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 */

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

	va_start(args, fmt);
	i = vsnprintf(buf, size, fmt, args);
	va_end(args);
	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
1386
 * 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.
1390
 * You probably want sprintf() instead.
1391 1392
 *
 * 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
1407
 * into @buf. Use snprintf() or scnprintf() in order to avoid
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 * buffer overflows.
1409 1410
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
int sprintf(char * buf, const char *fmt, ...)
{
	va_list args;
	int i;

	va_start(args, fmt);
	i=vsnprintf(buf, INT_MAX, fmt, args);
	va_end(args);
	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)
{
1450
	struct printf_spec spec = {0};
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	char *str, *end;
1452
	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)


1478 1479
	while (*fmt) {
		read = format_decode(fmt, &spec);
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1481
		fmt += read;
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1483 1484 1485 1486
		switch (spec.type) {
		case FORMAT_TYPE_NONE:
			break;

1487
		case FORMAT_TYPE_WIDTH:
1488 1489 1490 1491 1492
		case FORMAT_TYPE_PRECISION:
			save_arg(int);
			break;

		case FORMAT_TYPE_CHAR:
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			save_arg(char);
1494 1495 1496
			break;

		case FORMAT_TYPE_STR: {
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			const char *save_str = va_arg(args, char *);
			size_t len;
1499

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			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
					|| (unsigned long)save_str < PAGE_SIZE)
1502
				save_str = "(null)";
1503 1504 1505 1506
			len = strlen(save_str) + 1;
			if (str + len < end)
				memcpy(str, save_str, len);
			str += len;
1507
			break;
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		}
1509 1510

		case FORMAT_TYPE_PTR:
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			save_arg(void *);
			/* skip all alphanumeric pointer suffixes */
1513
			while (isalnum(*fmt))
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1514
				fmt++;
1515 1516 1517 1518 1519 1520 1521 1522 1523
			break;

		case FORMAT_TYPE_PERCENT_CHAR:
			break;

		case FORMAT_TYPE_INVALID:
			break;

		case FORMAT_TYPE_NRCHARS: {
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			/* skip %n 's argument */
1525
			int qualifier = spec.qualifier;
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			void *skip_arg;
			if (qualifier == 'l')
				skip_arg = va_arg(args, long *);
			else if (qualifier == 'Z' || qualifier == 'z')
				skip_arg = va_arg(args, size_t *);
			else
				skip_arg = va_arg(args, int *);
1533
			break;
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		}
1535 1536 1537 1538 1539

		default:
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
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				save_arg(long long);
1541 1542 1543
				break;
			case FORMAT_TYPE_ULONG:
			case FORMAT_TYPE_LONG:
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				save_arg(unsigned long);
1545 1546
				break;
			case FORMAT_TYPE_SIZE_T:
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1547
				save_arg(size_t);
1548 1549
				break;
			case FORMAT_TYPE_PTRDIFF:
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				save_arg(ptrdiff_t);
1551
				break;
1552 1553 1554 1555
			case FORMAT_TYPE_UBYTE:
			case FORMAT_TYPE_BYTE:
				save_arg(char);
				break;
1556 1557
			case FORMAT_TYPE_USHORT:
			case FORMAT_TYPE_SHORT:
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1558
				save_arg(short);
1559 1560
				break;
			default:
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1561
				save_arg(int);
1562
			}
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		}
	}
	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1566 1567

#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:
1583
 *  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;

1599
	struct printf_spec spec = {0};
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	if (WARN_ON_ONCE((int) size < 0))
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		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;
	}

1628 1629 1630
	while (*fmt) {
		int read;
		const char *old_fmt = fmt;
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1631

1632
		read = format_decode(fmt, &spec);
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1633

1634
		fmt += read;
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1636 1637 1638 1639 1640 1641 1642
		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
Lai Jiangshan 已提交
1643
			}
1644 1645
			str += read;
			break;
L
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1646 1647
		}

1648
		case FORMAT_TYPE_WIDTH:
1649 1650
			spec.field_width = get_arg(int);
			break;
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1651

1652 1653 1654
		case FORMAT_TYPE_PRECISION:
			spec.precision = get_arg(int);
			break;
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1655

1656 1657 1658
		case FORMAT_TYPE_CHAR:
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
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1659 1660 1661 1662 1663 1664 1665 1666 1667
					if (str < end)
						*str = ' ';
					++str;
				}
			}
			c = (unsigned char) get_arg(char);
			if (str < end)
				*str = c;
			++str;
1668
			while (--spec.field_width > 0) {
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1669 1670 1671 1672
				if (str < end)
					*str = ' ';
				++str;
			}
1673
			break;
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1675
		case FORMAT_TYPE_STR: {
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1676 1677 1678
			const char *str_arg = args;
			size_t len = strlen(str_arg);
			args += len + 1;
1679 1680
			str = string(str, end, (char *)str_arg, spec);
			break;
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1681 1682
		}

1683 1684 1685
		case FORMAT_TYPE_PTR:
			str = pointer(fmt+1, str, end, get_arg(void *), spec);
			while (isalnum(*fmt))
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1686
				fmt++;
1687
			break;
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1689
		case FORMAT_TYPE_PERCENT_CHAR:
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			if (str < end)
				*str = '%';
			++str;
			break;

1695
		case FORMAT_TYPE_INVALID:
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			if (str < end)
				*str = '%';
			++str;
1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722
			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;
1723 1724 1725 1726 1727 1728
			case FORMAT_TYPE_UBYTE:
				num = get_arg(unsigned char);
				break;
			case FORMAT_TYPE_BYTE:
				num = get_arg(signed char);
				break;
1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742
			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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1743 1744
		}
	}
1745

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	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
			end[-1] = '\0';
	}
1752

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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);
	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
 */
int vsscanf(const char * buf, const char * fmt, va_list args)
{
	const char *str = buf;
	char *next;
	char digit;
	int num = 0;
	int qualifier;
	int base;
	int field_width;
	int is_sign = 0;

	while(*fmt && *str) {
		/* 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;
		
		/* skip this conversion.
		 * advance both strings to next white space
		 */
		if (*fmt == '*') {
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1828
			while (!isspace(*fmt) && *fmt != '%' && *fmt)
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1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
				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;
		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
		    *fmt == 'Z' || *fmt == 'z') {
			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;

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

			/* now copy until next white space */
			while (*str && !isspace(*str) && field_width--) {
				*s++ = *str++;
			}
			*s = '\0';
			num++;
		}
		continue;
		case 'n':
			/* return number of characters read so far */
		{
			int *i = (int *)va_arg(args,int*);
			*i = str - buf;
		}
		continue;
		case 'o':
			base = 8;
			break;
		case 'x':
		case 'X':
			base = 16;
			break;
		case 'i':
                        base = 0;
		case 'd':
			is_sign = 1;
		case 'u':
			break;
		case '%':
			/* looking for '%' in str */
			if (*str++ != '%') 
				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
                    || (base == 16 && !isxdigit(digit))
                    || (base == 10 && !isdigit(digit))
                    || (base == 8 && (!isdigit(digit) || digit > '7'))
                    || (base == 0 && !isdigit(digit)))
				break;

		switch(qualifier) {
		case 'H':	/* that's 'hh' in format */
			if (is_sign) {
				signed char *s = (signed char *) va_arg(args,signed char *);
				*s = (signed char) simple_strtol(str,&next,base);
			} else {
				unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
				*s = (unsigned char) simple_strtoul(str, &next, base);
			}
			break;
		case 'h':
			if (is_sign) {
				short *s = (short *) va_arg(args,short *);
				*s = (short) simple_strtol(str,&next,base);
			} else {
				unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
				*s = (unsigned short) simple_strtoul(str, &next, base);
			}
			break;
		case 'l':
			if (is_sign) {
				long *l = (long *) va_arg(args,long *);
				*l = simple_strtol(str,&next,base);
			} else {
				unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
				*l = simple_strtoul(str,&next,base);
			}
			break;
		case 'L':
			if (is_sign) {
				long long *l = (long long*) va_arg(args,long long *);
				*l = simple_strtoll(str,&next,base);
			} else {
				unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
				*l = simple_strtoull(str,&next,base);
			}
			break;
		case 'Z':
		case 'z':
		{
			size_t *s = (size_t*) va_arg(args,size_t*);
			*s = (size_t) simple_strtoul(str,&next,base);
		}
		break;
		default:
			if (is_sign) {
				int *i = (int *) va_arg(args, int*);
				*i = (int) simple_strtol(str,&next,base);
			} else {
				unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
				*i = (unsigned int) simple_strtoul(str,&next,base);
			}
			break;
		}
		num++;

		if (!next)
			break;
		str = next;
	}
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

	/*
	 * 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;
	}

L
Linus Torvalds 已提交
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028
	return num;
}
EXPORT_SYMBOL(vsscanf);

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

	va_start(args,fmt);
	i = vsscanf(buf,fmt,args);
	va_end(args);
	return i;
}
EXPORT_SYMBOL(sscanf);