vsprintf.c 46.7 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,
	};
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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)];

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':
894 895
		ptr = dereference_function_descriptor(ptr);
		/* Fallthrough */
896
	case 's':
897
	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
 */
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	unsigned long long num;
1159
	char *str, *end;
1160
	struct printf_spec spec = {0};
L
Linus Torvalds 已提交
1161

1162 1163
	/* Reject out-of-range values early.  Large positive sizes are
	   used for unknown buffer sizes. */
1164
	if (WARN_ON_ONCE((int) size < 0))
L
Linus Torvalds 已提交
1165 1166 1167
		return 0;

	str = buf;
1168
	end = buf + size;
L
Linus Torvalds 已提交
1169

1170 1171 1172 1173
	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
L
Linus Torvalds 已提交
1174 1175
	}

1176 1177
	while (*fmt) {
		const char *old_fmt = fmt;
1178
		int read = format_decode(fmt, &spec);
L
Linus Torvalds 已提交
1179

1180
		fmt += read;
L
Linus Torvalds 已提交
1181

1182 1183 1184 1185 1186 1187 1188
		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
1189
			}
1190 1191
			str += read;
			break;
L
Linus Torvalds 已提交
1192 1193
		}

1194
		case FORMAT_TYPE_WIDTH:
1195 1196
			spec.field_width = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1197

1198 1199 1200
		case FORMAT_TYPE_PRECISION:
			spec.precision = va_arg(args, int);
			break;
L
Linus Torvalds 已提交
1201

1202 1203 1204
		case FORMAT_TYPE_CHAR: {
			char c;

1205 1206
			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;
1223
		}
L
Linus Torvalds 已提交
1224

1225 1226 1227
		case FORMAT_TYPE_STR:
			str = string(str, end, va_arg(args, char *), spec);
			break;
L
Linus Torvalds 已提交
1228

1229 1230 1231 1232 1233 1234
		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
1235

1236 1237 1238 1239 1240
		case FORMAT_TYPE_PERCENT_CHAR:
			if (str < end)
				*str = '%';
			++str;
			break;
L
Linus Torvalds 已提交
1241

1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253
		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);
1254
			} else if (TOLOWER(qualifier) == 'z') {
1255 1256 1257 1258 1259 1260 1261
				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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		}
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280

		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;
1281 1282 1283 1284 1285 1286
			case FORMAT_TYPE_UBYTE:
				num = (unsigned char) va_arg(args, int);
				break;
			case FORMAT_TYPE_BYTE:
				num = (signed char) va_arg(args, int);
				break;
1287 1288 1289 1290 1291 1292
			case FORMAT_TYPE_USHORT:
				num = (unsigned short) va_arg(args, int);
				break;
			case FORMAT_TYPE_SHORT:
				num = (short) va_arg(args, int);
				break;
1293 1294
			case FORMAT_TYPE_INT:
				num = (int) va_arg(args, int);
1295 1296 1297 1298 1299 1300
				break;
			default:
				num = va_arg(args, unsigned int);
			}

			str = number(str, end, num, spec);
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		}
	}
1303

1304 1305 1306 1307
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
1308
			end[-1] = '\0';
1309
	}
1310

1311
	/* the trailing null byte doesn't count towards the total */
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	return str-buf;
1313

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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.
1329
 * You probably want scnprintf() instead.
1330 1331
 *
 * 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;

1337 1338
	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.
1354 1355
 *
 * See the vsnprintf() documentation for format string extensions over C99.
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 */
1357
int snprintf(char *buf, size_t size, const char *fmt, ...)
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{
	va_list args;
	int i;

	va_start(args, fmt);
1363
	i = vsnprintf(buf, size, fmt, args);
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	va_end(args);
1365

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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
1378
 * the trailing '\0'. If @size is <= 0 the function returns 0.
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 */

1381
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);
1389

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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
1401
 * 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.
1405
 * You probably want sprintf() instead.
1406 1407
 *
 * 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
1422
 * into @buf. Use snprintf() or scnprintf() in order to avoid
L
Linus Torvalds 已提交
1423
 * buffer overflows.
1424 1425
 *
 * See the vsnprintf() documentation for format string extensions over C99.
L
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1426
 */
1427
int sprintf(char *buf, const char *fmt, ...)
L
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1428 1429 1430 1431 1432
{
	va_list args;
	int i;

	va_start(args, fmt);
1433
	i = vsnprintf(buf, INT_MAX, fmt, args);
L
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1434
	va_end(args);
1435

L
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1436 1437 1438 1439
	return i;
}
EXPORT_SYMBOL(sprintf);

1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465
#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)
{
1466
	struct printf_spec spec = {0};
1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491
	char *str, *end;

	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
	while (*fmt) {
1493
		int read = format_decode(fmt, &spec);
1494

1495
		fmt += read;
1496

1497 1498
		switch (spec.type) {
		case FORMAT_TYPE_NONE:
1499 1500
		case FORMAT_TYPE_INVALID:
		case FORMAT_TYPE_PERCENT_CHAR:
1501 1502
			break;

1503
		case FORMAT_TYPE_WIDTH:
1504 1505 1506 1507 1508
		case FORMAT_TYPE_PRECISION:
			save_arg(int);
			break;

		case FORMAT_TYPE_CHAR:
1509
			save_arg(char);
1510 1511 1512
			break;

		case FORMAT_TYPE_STR: {
1513 1514
			const char *save_str = va_arg(args, char *);
			size_t len;
1515

1516 1517
			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
					|| (unsigned long)save_str < PAGE_SIZE)
1518
				save_str = "(null)";
1519 1520 1521 1522
			len = strlen(save_str) + 1;
			if (str + len < end)
				memcpy(str, save_str, len);
			str += len;
1523
			break;
1524
		}
1525 1526

		case FORMAT_TYPE_PTR:
1527 1528
			save_arg(void *);
			/* skip all alphanumeric pointer suffixes */
1529
			while (isalnum(*fmt))
1530
				fmt++;
1531 1532 1533
			break;

		case FORMAT_TYPE_NRCHARS: {
1534
			/* skip %n 's argument */
1535
			int qualifier = spec.qualifier;
1536 1537 1538
			void *skip_arg;
			if (qualifier == 'l')
				skip_arg = va_arg(args, long *);
1539
			else if (TOLOWER(qualifier) == 'z')
1540 1541 1542
				skip_arg = va_arg(args, size_t *);
			else
				skip_arg = va_arg(args, int *);
1543
			break;
1544
		}
1545 1546 1547 1548 1549

		default:
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
1550
				save_arg(long long);
1551 1552 1553
				break;
			case FORMAT_TYPE_ULONG:
			case FORMAT_TYPE_LONG:
1554
				save_arg(unsigned long);
1555 1556
				break;
			case FORMAT_TYPE_SIZE_T:
1557
				save_arg(size_t);
1558 1559
				break;
			case FORMAT_TYPE_PTRDIFF:
1560
				save_arg(ptrdiff_t);
1561
				break;
1562 1563 1564 1565
			case FORMAT_TYPE_UBYTE:
			case FORMAT_TYPE_BYTE:
				save_arg(char);
				break;
1566 1567
			case FORMAT_TYPE_USHORT:
			case FORMAT_TYPE_SHORT:
1568
				save_arg(short);
1569 1570
				break;
			default:
1571
				save_arg(int);
1572
			}
1573 1574
		}
	}
1575

1576
	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1577
#undef save_arg
1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592
}
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:
1593
 *  see vsnprintf comment for details.
1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604
 *
 * 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)
{
1605
	struct printf_spec spec = {0};
1606 1607
	char *str, *end;
	const char *args = (const char *)bin_buf;
1608

1609
	if (WARN_ON_ONCE((int) size < 0))
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635
		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;
	}

1636 1637
	while (*fmt) {
		const char *old_fmt = fmt;
1638
		int read = format_decode(fmt, &spec);
1639

1640
		fmt += read;
1641

1642 1643 1644 1645 1646 1647 1648
		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);
1649
			}
1650 1651
			str += read;
			break;
1652 1653
		}

1654
		case FORMAT_TYPE_WIDTH:
1655 1656
			spec.field_width = get_arg(int);
			break;
1657

1658 1659 1660
		case FORMAT_TYPE_PRECISION:
			spec.precision = get_arg(int);
			break;
1661

1662 1663 1664
		case FORMAT_TYPE_CHAR: {
			char c;

1665 1666
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
1667 1668 1669 1670 1671 1672 1673 1674 1675
					if (str < end)
						*str = ' ';
					++str;
				}
			}
			c = (unsigned char) get_arg(char);
			if (str < end)
				*str = c;
			++str;
1676
			while (--spec.field_width > 0) {
1677 1678 1679 1680
				if (str < end)
					*str = ' ';
				++str;
			}
1681
			break;
1682
		}
1683

1684
		case FORMAT_TYPE_STR: {
1685
			const char *str_arg = args;
1686
			args += strlen(str_arg) + 1;
1687 1688
			str = string(str, end, (char *)str_arg, spec);
			break;
1689 1690
		}

1691 1692 1693
		case FORMAT_TYPE_PTR:
			str = pointer(fmt+1, str, end, get_arg(void *), spec);
			while (isalnum(*fmt))
1694
				fmt++;
1695
			break;
1696

1697 1698
		case FORMAT_TYPE_PERCENT_CHAR:
		case FORMAT_TYPE_INVALID:
1699 1700 1701
			if (str < end)
				*str = '%';
			++str;
1702 1703 1704 1705 1706 1707
			break;

		case FORMAT_TYPE_NRCHARS:
			/* skip */
			break;

1708 1709 1710
		default: {
			unsigned long long num;

1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
				num = get_arg(long long);
				break;
			case FORMAT_TYPE_ULONG:
			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;
1726 1727 1728 1729 1730 1731
			case FORMAT_TYPE_UBYTE:
				num = get_arg(unsigned char);
				break;
			case FORMAT_TYPE_BYTE:
				num = get_arg(signed char);
				break;
1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745
			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);
1746 1747 1748
		} /* default: */
		} /* switch(spec.type) */
	} /* while(*fmt) */
1749

1750 1751 1752 1753 1754 1755
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
			end[-1] = '\0';
	}
1756

1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781
#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);
1782

1783 1784 1785 1786 1787 1788
	return ret;
}
EXPORT_SYMBOL_GPL(bprintf);

#endif /* CONFIG_BINARY_PRINTF */

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1789 1790 1791 1792 1793 1794
/**
 * vsscanf - Unformat a buffer into a list of arguments
 * @buf:	input buffer
 * @fmt:	format of buffer
 * @args:	arguments
 */
1795
int vsscanf(const char *buf, const char *fmt, va_list args)
L
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1796 1797 1798 1799 1800
{
	const char *str = buf;
	char *next;
	char digit;
	int num = 0;
1801
	int qualifier, base, field_width;
1802
	bool is_sign;
L
Linus Torvalds 已提交
1803

1804
	while (*fmt && *str) {
L
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1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825
		/* 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;
1826

L
Linus Torvalds 已提交
1827 1828 1829 1830
		/* skip this conversion.
		 * advance both strings to next white space
		 */
		if (*fmt == '*') {
A
Andy Spencer 已提交
1831
			while (!isspace(*fmt) && *fmt != '%' && *fmt)
L
Linus Torvalds 已提交
1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844
				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;
1845 1846
		if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
		    TOLOWER(*fmt) == 'z') {
L
Linus Torvalds 已提交
1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861
			qualifier = *fmt++;
			if (unlikely(qualifier == *fmt)) {
				if (qualifier == 'h') {
					qualifier = 'H';
					fmt++;
				} else if (qualifier == 'l') {
					qualifier = 'L';
					fmt++;
				}
			}
		}

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

1862 1863 1864
		base = 10;
		is_sign = 0;

1865
		switch (*fmt++) {
L
Linus Torvalds 已提交
1866 1867
		case 'c':
		{
1868
			char *s = (char *)va_arg(args, char*);
L
Linus Torvalds 已提交
1869 1870 1871 1872 1873 1874 1875 1876 1877 1878
			if (field_width == -1)
				field_width = 1;
			do {
				*s++ = *str++;
			} while (--field_width > 0 && *str);
			num++;
		}
		continue;
		case 's':
		{
1879 1880
			char *s = (char *)va_arg(args, char *);
			if (field_width == -1)
L
Linus Torvalds 已提交
1881 1882 1883 1884 1885 1886
				field_width = INT_MAX;
			/* first, skip leading white space in buffer */
			while (isspace(*str))
				str++;

			/* now copy until next white space */
1887
			while (*str && !isspace(*str) && field_width--)
L
Linus Torvalds 已提交
1888 1889 1890 1891 1892 1893 1894 1895
				*s++ = *str++;
			*s = '\0';
			num++;
		}
		continue;
		case 'n':
			/* return number of characters read so far */
		{
1896
			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':
1908
			base = 0;
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		case 'd':
			is_sign = 1;
		case 'u':
			break;
		case '%':
			/* looking for '%' in str */
1915
			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
1934 1935 1936 1937 1938
		    || (base == 16 && !isxdigit(digit))
		    || (base == 10 && !isdigit(digit))
		    || (base == 8 && (!isdigit(digit) || digit > '7'))
		    || (base == 0 && !isdigit(digit)))
			break;
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1940
		switch (qualifier) {
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		case 'H':	/* that's 'hh' in format */
			if (is_sign) {
1943 1944
				signed char *s = (signed char *)va_arg(args, signed char *);
				*s = (signed char)simple_strtol(str, &next, base);
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			} else {
1946 1947
				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) {
1952 1953
				short *s = (short *)va_arg(args, short *);
				*s = (short)simple_strtol(str, &next, base);
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			} else {
1955 1956
				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) {
1961 1962
				long *l = (long *)va_arg(args, long *);
				*l = simple_strtol(str, &next, base);
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			} else {
1964 1965
				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) {
1970 1971
				long long *l = (long long *)va_arg(args, long long *);
				*l = simple_strtoll(str, &next, base);
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			} else {
1973 1974
				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':
		{
1980 1981
			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) {
1986 1987
				int *i = (int *)va_arg(args, int *);
				*i = (int)simple_strtol(str, &next, base);
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			} else {
1989 1990
				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;
	}
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

	/*
	 * 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
 */
2021
int sscanf(const char *buf, const char *fmt, ...)
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{
	va_list args;
	int i;

2026 2027
	va_start(args, fmt);
	i = vsscanf(buf, fmt, args);
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	va_end(args);
2029

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	return i;
}
EXPORT_SYMBOL(sscanf);
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