1/*
   2 *  linux/lib/vsprintf.c
   3 *
   4 *  Copyright (C) 1991, 1992  Linus Torvalds
   5 */
   6
   7/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
   8/*
   9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
  10 */
  11
  12/*
  13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
  14 * - changed to provide snprintf and vsnprintf functions
  15 * So Feb  1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
  16 * - scnprintf and vscnprintf
  17 */
  18
  19#include <stdarg.h>
 
 
  20#include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
  21#include <linux/types.h>
  22#include <linux/string.h>
  23#include <linux/ctype.h>
  24#include <linux/kernel.h>
  25#include <linux/kallsyms.h>
  26#include <linux/math64.h>
  27#include <linux/uaccess.h>
  28#include <linux/ioport.h>
  29#include <linux/dcache.h>
  30#include <linux/cred.h>
 
  31#include <net/addrconf.h>
 
 
 
 
 
  32
  33#include <asm/page.h>		/* for PAGE_SIZE */
  34#include <asm/sections.h>	/* for dereference_function_descriptor() */
 
  35
 
  36#include "kstrtox.h"
  37
  38/**
  39 * simple_strtoull - convert a string to an unsigned long long
  40 * @cp: The start of the string
  41 * @endp: A pointer to the end of the parsed string will be placed here
  42 * @base: The number base to use
  43 *
  44 * This function is obsolete. Please use kstrtoull instead.
  45 */
  46unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
  47{
  48	unsigned long long result;
  49	unsigned int rv;
  50
  51	cp = _parse_integer_fixup_radix(cp, &base);
  52	rv = _parse_integer(cp, base, &result);
  53	/* FIXME */
  54	cp += (rv & ~KSTRTOX_OVERFLOW);
  55
  56	if (endp)
  57		*endp = (char *)cp;
  58
  59	return result;
  60}
  61EXPORT_SYMBOL(simple_strtoull);
  62
  63/**
  64 * simple_strtoul - convert a string to an unsigned long
  65 * @cp: The start of the string
  66 * @endp: A pointer to the end of the parsed string will be placed here
  67 * @base: The number base to use
  68 *
  69 * This function is obsolete. Please use kstrtoul instead.
  70 */
  71unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  72{
  73	return simple_strtoull(cp, endp, base);
  74}
  75EXPORT_SYMBOL(simple_strtoul);
  76
  77/**
  78 * simple_strtol - convert a string to a signed long
  79 * @cp: The start of the string
  80 * @endp: A pointer to the end of the parsed string will be placed here
  81 * @base: The number base to use
  82 *
  83 * This function is obsolete. Please use kstrtol instead.
  84 */
  85long simple_strtol(const char *cp, char **endp, unsigned int base)
  86{
  87	if (*cp == '-')
  88		return -simple_strtoul(cp + 1, endp, base);
  89
  90	return simple_strtoul(cp, endp, base);
  91}
  92EXPORT_SYMBOL(simple_strtol);
  93
  94/**
  95 * simple_strtoll - convert a string to a signed long long
  96 * @cp: The start of the string
  97 * @endp: A pointer to the end of the parsed string will be placed here
  98 * @base: The number base to use
  99 *
 100 * This function is obsolete. Please use kstrtoll instead.
 101 */
 102long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 103{
 104	if (*cp == '-')
 105		return -simple_strtoull(cp + 1, endp, base);
 106
 107	return simple_strtoull(cp, endp, base);
 108}
 109EXPORT_SYMBOL(simple_strtoll);
 110
 111static noinline_for_stack
 112int skip_atoi(const char **s)
 113{
 114	int i = 0;
 115
 116	while (isdigit(**s))
 117		i = i*10 + *((*s)++) - '0';
 
 118
 119	return i;
 120}
 121
 122/* Decimal conversion is by far the most typical, and is used
 123 * for /proc and /sys data. This directly impacts e.g. top performance
 124 * with many processes running. We optimize it for speed
 125 * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
 126 * (with permission from the author, Douglas W. Jones).
 127 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 128
 129#if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
 130/* Formats correctly any integer in [0, 999999999] */
 
 
 
 
 131static noinline_for_stack
 132char *put_dec_full9(char *buf, unsigned q)
 133{
 134	unsigned r;
 135
 136	/*
 137	 * Possible ways to approx. divide by 10
 138	 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
 139	 * (x * 0xcccd) >> 19     x <      81920 (x < 262149 when 64-bit mul)
 140	 * (x * 0x6667) >> 18     x <      43699
 141	 * (x * 0x3334) >> 17     x <      16389
 142	 * (x * 0x199a) >> 16     x <      16389
 143	 * (x * 0x0ccd) >> 15     x <      16389
 144	 * (x * 0x0667) >> 14     x <       2739
 145	 * (x * 0x0334) >> 13     x <       1029
 146	 * (x * 0x019a) >> 12     x <       1029
 147	 * (x * 0x00cd) >> 11     x <       1029 shorter code than * 0x67 (on i386)
 148	 * (x * 0x0067) >> 10     x <        179
 149	 * (x * 0x0034) >>  9     x <         69 same
 150	 * (x * 0x001a) >>  8     x <         69 same
 151	 * (x * 0x000d) >>  7     x <         69 same, shortest code (on i386)
 152	 * (x * 0x0007) >>  6     x <         19
 153	 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
 154	 */
 155	r      = (q * (uint64_t)0x1999999a) >> 32;
 156	*buf++ = (q - 10 * r) + '0'; /* 1 */
 157	q      = (r * (uint64_t)0x1999999a) >> 32;
 158	*buf++ = (r - 10 * q) + '0'; /* 2 */
 159	r      = (q * (uint64_t)0x1999999a) >> 32;
 160	*buf++ = (q - 10 * r) + '0'; /* 3 */
 161	q      = (r * (uint64_t)0x1999999a) >> 32;
 162	*buf++ = (r - 10 * q) + '0'; /* 4 */
 163	r      = (q * (uint64_t)0x1999999a) >> 32;
 164	*buf++ = (q - 10 * r) + '0'; /* 5 */
 165	/* Now value is under 10000, can avoid 64-bit multiply */
 166	q      = (r * 0x199a) >> 16;
 167	*buf++ = (r - 10 * q)  + '0'; /* 6 */
 168	r      = (q * 0xcd) >> 11;
 169	*buf++ = (q - 10 * r)  + '0'; /* 7 */
 170	q      = (r * 0xcd) >> 11;
 171	*buf++ = (r - 10 * q) + '0'; /* 8 */
 172	*buf++ = q + '0'; /* 9 */
 173	return buf;
 174}
 175#endif
 176
 177/* Similar to above but do not pad with zeros.
 178 * Code can be easily arranged to print 9 digits too, but our callers
 179 * always call put_dec_full9() instead when the number has 9 decimal digits.
 180 */
 181static noinline_for_stack
 182char *put_dec_trunc8(char *buf, unsigned r)
 183{
 184	unsigned q;
 185
 186	/* Copy of previous function's body with added early returns */
 187	while (r >= 10000) {
 188		q = r + '0';
 189		r  = (r * (uint64_t)0x1999999a) >> 32;
 190		*buf++ = q - 10*r;
 191	}
 192
 193	q      = (r * 0x199a) >> 16;	/* r <= 9999 */
 194	*buf++ = (r - 10 * q)  + '0';
 195	if (q == 0)
 196		return buf;
 197	r      = (q * 0xcd) >> 11;	/* q <= 999 */
 198	*buf++ = (q - 10 * r)  + '0';
 199	if (r == 0)
 200		return buf;
 201	q      = (r * 0xcd) >> 11;	/* r <= 99 */
 202	*buf++ = (r - 10 * q) + '0';
 203	if (q == 0)
 204		return buf;
 205	*buf++ = q + '0';		 /* q <= 9 */
 206	return buf;
 207}
 208
 209/* There are two algorithms to print larger numbers.
 210 * One is generic: divide by 1000000000 and repeatedly print
 211 * groups of (up to) 9 digits. It's conceptually simple,
 212 * but requires a (unsigned long long) / 1000000000 division.
 213 *
 214 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
 215 * manipulates them cleverly and generates groups of 4 decimal digits.
 216 * It so happens that it does NOT require long long division.
 217 *
 218 * If long is > 32 bits, division of 64-bit values is relatively easy,
 219 * and we will use the first algorithm.
 220 * If long long is > 64 bits (strange architecture with VERY large long long),
 221 * second algorithm can't be used, and we again use the first one.
 222 *
 223 * Else (if long is 32 bits and long long is 64 bits) we use second one.
 224 */
 225
 226#if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
 227
 228/* First algorithm: generic */
 229
 230static
 231char *put_dec(char *buf, unsigned long long n)
 232{
 233	if (n >= 100*1000*1000) {
 234		while (n >= 1000*1000*1000)
 235			buf = put_dec_full9(buf, do_div(n, 1000*1000*1000));
 236		if (n >= 100*1000*1000)
 237			return put_dec_full9(buf, n);
 238	}
 239	return put_dec_trunc8(buf, n);
 240}
 241
 242#else
 243
 244/* Second algorithm: valid only for 64-bit long longs */
 245
 246/* See comment in put_dec_full9 for choice of constants */
 247static noinline_for_stack
 248void put_dec_full4(char *buf, unsigned q)
 249{
 250	unsigned r;
 251	r      = (q * 0xccd) >> 15;
 252	buf[0] = (q - 10 * r) + '0';
 253	q      = (r * 0xcd) >> 11;
 254	buf[1] = (r - 10 * q)  + '0';
 255	r      = (q * 0xcd) >> 11;
 256	buf[2] = (q - 10 * r)  + '0';
 257	buf[3] = r + '0';
 258}
 259
 260/*
 261 * Call put_dec_full4 on x % 10000, return x / 10000.
 262 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 263 * holds for all x < 1,128,869,999.  The largest value this
 264 * helper will ever be asked to convert is 1,125,520,955.
 265 * (d1 in the put_dec code, assuming n is all-ones).
 266 */
 267static
 268unsigned put_dec_helper4(char *buf, unsigned x)
 269{
 270        uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
 271
 272        put_dec_full4(buf, x - q * 10000);
 273        return q;
 274}
 275
 276/* Based on code by Douglas W. Jones found at
 277 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 278 * (with permission from the author).
 279 * Performs no 64-bit division and hence should be fast on 32-bit machines.
 280 */
 281static
 282char *put_dec(char *buf, unsigned long long n)
 283{
 284	uint32_t d3, d2, d1, q, h;
 285
 286	if (n < 100*1000*1000)
 287		return put_dec_trunc8(buf, n);
 288
 289	d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
 290	h   = (n >> 32);
 291	d2  = (h      ) & 0xffff;
 292	d3  = (h >> 16); /* implicit "& 0xffff" */
 293
 
 
 294	q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
 295	q = put_dec_helper4(buf, q);
 296
 297	q += 7671 * d3 + 9496 * d2 + 6 * d1;
 298	q = put_dec_helper4(buf+4, q);
 299
 300	q += 4749 * d3 + 42 * d2;
 301	q = put_dec_helper4(buf+8, q);
 302
 303	q += 281 * d3;
 304	buf += 12;
 305	if (q)
 306		buf = put_dec_trunc8(buf, q);
 307	else while (buf[-1] == '0')
 308		--buf;
 309
 310	return buf;
 311}
 312
 313#endif
 314
 315/*
 316 * Convert passed number to decimal string.
 317 * Returns the length of string.  On buffer overflow, returns 0.
 318 *
 319 * If speed is not important, use snprintf(). It's easy to read the code.
 320 */
 321int num_to_str(char *buf, int size, unsigned long long num)
 322{
 323	char tmp[sizeof(num) * 3];
 
 324	int idx, len;
 325
 326	/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 327	if (num <= 9) {
 328		tmp[0] = '0' + num;
 329		len = 1;
 330	} else {
 331		len = put_dec(tmp, num) - tmp;
 332	}
 333
 334	if (len > size)
 335		return 0;
 336	for (idx = 0; idx < len; ++idx)
 337		buf[idx] = tmp[len - idx - 1];
 338	return len;
 339}
 340
 341#define ZEROPAD	1		/* pad with zero */
 342#define SIGN	2		/* unsigned/signed long */
 343#define PLUS	4		/* show plus */
 344#define SPACE	8		/* space if plus */
 345#define LEFT	16		/* left justified */
 346#define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
 347#define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
 348
 349enum format_type {
 350	FORMAT_TYPE_NONE, /* Just a string part */
 351	FORMAT_TYPE_WIDTH,
 352	FORMAT_TYPE_PRECISION,
 353	FORMAT_TYPE_CHAR,
 354	FORMAT_TYPE_STR,
 355	FORMAT_TYPE_PTR,
 356	FORMAT_TYPE_PERCENT_CHAR,
 357	FORMAT_TYPE_INVALID,
 358	FORMAT_TYPE_LONG_LONG,
 359	FORMAT_TYPE_ULONG,
 360	FORMAT_TYPE_LONG,
 361	FORMAT_TYPE_UBYTE,
 362	FORMAT_TYPE_BYTE,
 363	FORMAT_TYPE_USHORT,
 364	FORMAT_TYPE_SHORT,
 365	FORMAT_TYPE_UINT,
 366	FORMAT_TYPE_INT,
 367	FORMAT_TYPE_SIZE_T,
 368	FORMAT_TYPE_PTRDIFF
 369};
 370
 371struct printf_spec {
 372	u8	type;		/* format_type enum */
 373	u8	flags;		/* flags to number() */
 374	u8	base;		/* number base, 8, 10 or 16 only */
 375	u8	qualifier;	/* number qualifier, one of 'hHlLtzZ' */
 376	s16	field_width;	/* width of output field */
 377	s16	precision;	/* # of digits/chars */
 378};
 
 379
 380static noinline_for_stack
 381char *number(char *buf, char *end, unsigned long long num,
 382	     struct printf_spec spec)
 383{
 384	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 385	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 386
 387	char tmp[66];
 388	char sign;
 389	char locase;
 390	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 391	int i;
 392	bool is_zero = num == 0LL;
 
 
 
 
 393
 394	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
 395	 * produces same digits or (maybe lowercased) letters */
 396	locase = (spec.flags & SMALL);
 397	if (spec.flags & LEFT)
 398		spec.flags &= ~ZEROPAD;
 399	sign = 0;
 400	if (spec.flags & SIGN) {
 401		if ((signed long long)num < 0) {
 402			sign = '-';
 403			num = -(signed long long)num;
 404			spec.field_width--;
 405		} else if (spec.flags & PLUS) {
 406			sign = '+';
 407			spec.field_width--;
 408		} else if (spec.flags & SPACE) {
 409			sign = ' ';
 410			spec.field_width--;
 411		}
 412	}
 413	if (need_pfx) {
 414		if (spec.base == 16)
 415			spec.field_width -= 2;
 416		else if (!is_zero)
 417			spec.field_width--;
 418	}
 419
 420	/* generate full string in tmp[], in reverse order */
 421	i = 0;
 422	if (num < spec.base)
 423		tmp[i++] = digits[num] | locase;
 424	/* Generic code, for any base:
 425	else do {
 426		tmp[i++] = (digits[do_div(num,base)] | locase);
 427	} while (num != 0);
 428	*/
 429	else if (spec.base != 10) { /* 8 or 16 */
 430		int mask = spec.base - 1;
 431		int shift = 3;
 432
 433		if (spec.base == 16)
 434			shift = 4;
 435		do {
 436			tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 437			num >>= shift;
 438		} while (num);
 439	} else { /* base 10 */
 440		i = put_dec(tmp, num) - tmp;
 441	}
 442
 443	/* printing 100 using %2d gives "100", not "00" */
 444	if (i > spec.precision)
 445		spec.precision = i;
 446	/* leading space padding */
 447	spec.field_width -= spec.precision;
 448	if (!(spec.flags & (ZEROPAD+LEFT))) {
 449		while (--spec.field_width >= 0) {
 450			if (buf < end)
 451				*buf = ' ';
 452			++buf;
 453		}
 454	}
 455	/* sign */
 456	if (sign) {
 457		if (buf < end)
 458			*buf = sign;
 459		++buf;
 460	}
 461	/* "0x" / "0" prefix */
 462	if (need_pfx) {
 463		if (spec.base == 16 || !is_zero) {
 464			if (buf < end)
 465				*buf = '0';
 466			++buf;
 467		}
 468		if (spec.base == 16) {
 469			if (buf < end)
 470				*buf = ('X' | locase);
 471			++buf;
 472		}
 473	}
 474	/* zero or space padding */
 475	if (!(spec.flags & LEFT)) {
 476		char c = (spec.flags & ZEROPAD) ? '0' : ' ';
 477		while (--spec.field_width >= 0) {
 
 478			if (buf < end)
 479				*buf = c;
 480			++buf;
 481		}
 482	}
 483	/* hmm even more zero padding? */
 484	while (i <= --spec.precision) {
 485		if (buf < end)
 486			*buf = '0';
 487		++buf;
 488	}
 489	/* actual digits of result */
 490	while (--i >= 0) {
 491		if (buf < end)
 492			*buf = tmp[i];
 493		++buf;
 494	}
 495	/* trailing space padding */
 496	while (--spec.field_width >= 0) {
 497		if (buf < end)
 498			*buf = ' ';
 499		++buf;
 500	}
 501
 502	return buf;
 503}
 504
 505static noinline_for_stack
 506char *string(char *buf, char *end, const char *s, struct printf_spec spec)
 507{
 508	int len, i;
 509
 510	if ((unsigned long)s < PAGE_SIZE)
 511		s = "(null)";
 512
 513	len = strnlen(s, spec.precision);
 514
 515	if (!(spec.flags & LEFT)) {
 516		while (len < spec.field_width--) {
 517			if (buf < end)
 518				*buf = ' ';
 519			++buf;
 520		}
 521	}
 522	for (i = 0; i < len; ++i) {
 523		if (buf < end)
 524			*buf = *s;
 525		++buf; ++s;
 526	}
 527	while (len < spec.field_width--) {
 528		if (buf < end)
 529			*buf = ' ';
 530		++buf;
 531	}
 532
 533	return buf;
 534}
 535
 536static void widen(char *buf, char *end, unsigned len, unsigned spaces)
 537{
 538	size_t size;
 539	if (buf >= end)	/* nowhere to put anything */
 540		return;
 541	size = end - buf;
 542	if (size <= spaces) {
 543		memset(buf, ' ', size);
 544		return;
 545	}
 546	if (len) {
 547		if (len > size - spaces)
 548			len = size - spaces;
 549		memmove(buf + spaces, buf, len);
 550	}
 551	memset(buf, ' ', spaces);
 552}
 553
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 554static noinline_for_stack
 555char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 556		  const char *fmt)
 557{
 558	const char *array[4], *s;
 559	const struct dentry *p;
 560	int depth;
 561	int i, n;
 562
 563	switch (fmt[1]) {
 564		case '2': case '3': case '4':
 565			depth = fmt[1] - '0';
 566			break;
 567		default:
 568			depth = 1;
 569	}
 570
 571	rcu_read_lock();
 572	for (i = 0; i < depth; i++, d = p) {
 573		p = ACCESS_ONCE(d->d_parent);
 574		array[i] = ACCESS_ONCE(d->d_name.name);
 575		if (p == d) {
 576			if (i)
 577				array[i] = "";
 578			i++;
 579			break;
 580		}
 581	}
 582	s = array[--i];
 583	for (n = 0; n != spec.precision; n++, buf++) {
 584		char c = *s++;
 585		if (!c) {
 586			if (!i)
 587				break;
 588			c = '/';
 589			s = array[--i];
 590		}
 591		if (buf < end)
 592			*buf = c;
 593	}
 594	rcu_read_unlock();
 595	if (n < spec.field_width) {
 596		/* we want to pad the sucker */
 597		unsigned spaces = spec.field_width - n;
 598		if (!(spec.flags & LEFT)) {
 599			widen(buf - n, end, n, spaces);
 600			return buf + spaces;
 601		}
 602		while (spaces--) {
 
 
 
 
 
 603			if (buf < end)
 604				*buf = ' ';
 605			++buf;
 606		}
 
 607	}
 608	return buf;
 609}
 
 610
 611static noinline_for_stack
 612char *symbol_string(char *buf, char *end, void *ptr,
 613		    struct printf_spec spec, const char *fmt)
 614{
 615	unsigned long value;
 616#ifdef CONFIG_KALLSYMS
 617	char sym[KSYM_SYMBOL_LEN];
 618#endif
 619
 620	if (fmt[1] == 'R')
 621		ptr = __builtin_extract_return_addr(ptr);
 622	value = (unsigned long)ptr;
 623
 624#ifdef CONFIG_KALLSYMS
 625	if (*fmt == 'B')
 626		sprint_backtrace(sym, value);
 627	else if (*fmt != 'f' && *fmt != 's')
 628		sprint_symbol(sym, value);
 629	else
 630		sprint_symbol_no_offset(sym, value);
 631
 632	return string(buf, end, sym, spec);
 633#else
 634	spec.field_width = 2 * sizeof(void *);
 635	spec.flags |= SPECIAL | SMALL | ZEROPAD;
 636	spec.base = 16;
 637
 638	return number(buf, end, value, spec);
 639#endif
 640}
 641
 642static noinline_for_stack
 643char *resource_string(char *buf, char *end, struct resource *res,
 644		      struct printf_spec spec, const char *fmt)
 645{
 646#ifndef IO_RSRC_PRINTK_SIZE
 647#define IO_RSRC_PRINTK_SIZE	6
 648#endif
 649
 650#ifndef MEM_RSRC_PRINTK_SIZE
 651#define MEM_RSRC_PRINTK_SIZE	10
 652#endif
 653	static const struct printf_spec io_spec = {
 654		.base = 16,
 655		.field_width = IO_RSRC_PRINTK_SIZE,
 656		.precision = -1,
 657		.flags = SPECIAL | SMALL | ZEROPAD,
 658	};
 659	static const struct printf_spec mem_spec = {
 660		.base = 16,
 661		.field_width = MEM_RSRC_PRINTK_SIZE,
 662		.precision = -1,
 663		.flags = SPECIAL | SMALL | ZEROPAD,
 664	};
 665	static const struct printf_spec bus_spec = {
 666		.base = 16,
 667		.field_width = 2,
 668		.precision = -1,
 669		.flags = SMALL | ZEROPAD,
 670	};
 671	static const struct printf_spec dec_spec = {
 672		.base = 10,
 673		.precision = -1,
 674		.flags = 0,
 675	};
 676	static const struct printf_spec str_spec = {
 677		.field_width = -1,
 678		.precision = 10,
 679		.flags = LEFT,
 680	};
 681	static const struct printf_spec flag_spec = {
 682		.base = 16,
 683		.precision = -1,
 684		.flags = SPECIAL | SMALL,
 685	};
 686
 687	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 688	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 689#define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
 690#define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
 691#define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
 692#define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
 693	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 694		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 695
 696	char *p = sym, *pend = sym + sizeof(sym);
 697	int decode = (fmt[0] == 'R') ? 1 : 0;
 698	const struct printf_spec *specp;
 699
 700	*p++ = '[';
 701	if (res->flags & IORESOURCE_IO) {
 702		p = string(p, pend, "io  ", str_spec);
 703		specp = &io_spec;
 704	} else if (res->flags & IORESOURCE_MEM) {
 705		p = string(p, pend, "mem ", str_spec);
 706		specp = &mem_spec;
 707	} else if (res->flags & IORESOURCE_IRQ) {
 708		p = string(p, pend, "irq ", str_spec);
 709		specp = &dec_spec;
 710	} else if (res->flags & IORESOURCE_DMA) {
 711		p = string(p, pend, "dma ", str_spec);
 712		specp = &dec_spec;
 713	} else if (res->flags & IORESOURCE_BUS) {
 714		p = string(p, pend, "bus ", str_spec);
 715		specp = &bus_spec;
 716	} else {
 717		p = string(p, pend, "??? ", str_spec);
 718		specp = &mem_spec;
 719		decode = 0;
 720	}
 721	if (decode && res->flags & IORESOURCE_UNSET) {
 722		p = string(p, pend, "size ", str_spec);
 723		p = number(p, pend, resource_size(res), *specp);
 724	} else {
 725		p = number(p, pend, res->start, *specp);
 726		if (res->start != res->end) {
 727			*p++ = '-';
 728			p = number(p, pend, res->end, *specp);
 729		}
 730	}
 731	if (decode) {
 732		if (res->flags & IORESOURCE_MEM_64)
 733			p = string(p, pend, " 64bit", str_spec);
 734		if (res->flags & IORESOURCE_PREFETCH)
 735			p = string(p, pend, " pref", str_spec);
 736		if (res->flags & IORESOURCE_WINDOW)
 737			p = string(p, pend, " window", str_spec);
 738		if (res->flags & IORESOURCE_DISABLED)
 739			p = string(p, pend, " disabled", str_spec);
 740	} else {
 741		p = string(p, pend, " flags ", str_spec);
 742		p = number(p, pend, res->flags, flag_spec);
 743	}
 744	*p++ = ']';
 745	*p = '\0';
 746
 747	return string(buf, end, sym, spec);
 748}
 749
 750static noinline_for_stack
 751char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
 752		 const char *fmt)
 753{
 754	int i, len = 1;		/* if we pass '%ph[CDN]', field width remains
 755				   negative value, fallback to the default */
 756	char separator;
 757
 758	if (spec.field_width == 0)
 759		/* nothing to print */
 760		return buf;
 761
 762	if (ZERO_OR_NULL_PTR(addr))
 763		/* NULL pointer */
 764		return string(buf, end, NULL, spec);
 765
 766	switch (fmt[1]) {
 767	case 'C':
 768		separator = ':';
 769		break;
 770	case 'D':
 771		separator = '-';
 772		break;
 773	case 'N':
 774		separator = 0;
 775		break;
 776	default:
 777		separator = ' ';
 778		break;
 779	}
 780
 781	if (spec.field_width > 0)
 782		len = min_t(int, spec.field_width, 64);
 783
 784	for (i = 0; i < len && buf < end - 1; i++) {
 785		buf = hex_byte_pack(buf, addr[i]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 786
 787		if (buf < end && separator && i != len - 1)
 788			*buf++ = separator;
 789	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 790
 
 
 791	return buf;
 792}
 793
 794static noinline_for_stack
 795char *mac_address_string(char *buf, char *end, u8 *addr,
 796			 struct printf_spec spec, const char *fmt)
 797{
 798	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
 799	char *p = mac_addr;
 800	int i;
 801	char separator;
 802	bool reversed = false;
 803
 804	switch (fmt[1]) {
 805	case 'F':
 806		separator = '-';
 807		break;
 808
 809	case 'R':
 810		reversed = true;
 811		/* fall through */
 812
 813	default:
 814		separator = ':';
 815		break;
 816	}
 817
 818	for (i = 0; i < 6; i++) {
 819		if (reversed)
 820			p = hex_byte_pack(p, addr[5 - i]);
 821		else
 822			p = hex_byte_pack(p, addr[i]);
 823
 824		if (fmt[0] == 'M' && i != 5)
 825			*p++ = separator;
 826	}
 827	*p = '\0';
 828
 829	return string(buf, end, mac_addr, spec);
 830}
 831
 832static noinline_for_stack
 833char *ip4_string(char *p, const u8 *addr, const char *fmt)
 834{
 835	int i;
 836	bool leading_zeros = (fmt[0] == 'i');
 837	int index;
 838	int step;
 839
 840	switch (fmt[2]) {
 841	case 'h':
 842#ifdef __BIG_ENDIAN
 843		index = 0;
 844		step = 1;
 845#else
 846		index = 3;
 847		step = -1;
 848#endif
 849		break;
 850	case 'l':
 851		index = 3;
 852		step = -1;
 853		break;
 854	case 'n':
 855	case 'b':
 856	default:
 857		index = 0;
 858		step = 1;
 859		break;
 860	}
 861	for (i = 0; i < 4; i++) {
 862		char temp[3];	/* hold each IP quad in reverse order */
 863		int digits = put_dec_trunc8(temp, addr[index]) - temp;
 864		if (leading_zeros) {
 865			if (digits < 3)
 866				*p++ = '0';
 867			if (digits < 2)
 868				*p++ = '0';
 869		}
 870		/* reverse the digits in the quad */
 871		while (digits--)
 872			*p++ = temp[digits];
 873		if (i < 3)
 874			*p++ = '.';
 875		index += step;
 876	}
 877	*p = '\0';
 878
 879	return p;
 880}
 881
 882static noinline_for_stack
 883char *ip6_compressed_string(char *p, const char *addr)
 884{
 885	int i, j, range;
 886	unsigned char zerolength[8];
 887	int longest = 1;
 888	int colonpos = -1;
 889	u16 word;
 890	u8 hi, lo;
 891	bool needcolon = false;
 892	bool useIPv4;
 893	struct in6_addr in6;
 894
 895	memcpy(&in6, addr, sizeof(struct in6_addr));
 896
 897	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
 898
 899	memset(zerolength, 0, sizeof(zerolength));
 900
 901	if (useIPv4)
 902		range = 6;
 903	else
 904		range = 8;
 905
 906	/* find position of longest 0 run */
 907	for (i = 0; i < range; i++) {
 908		for (j = i; j < range; j++) {
 909			if (in6.s6_addr16[j] != 0)
 910				break;
 911			zerolength[i]++;
 912		}
 913	}
 914	for (i = 0; i < range; i++) {
 915		if (zerolength[i] > longest) {
 916			longest = zerolength[i];
 917			colonpos = i;
 918		}
 919	}
 920	if (longest == 1)		/* don't compress a single 0 */
 921		colonpos = -1;
 922
 923	/* emit address */
 924	for (i = 0; i < range; i++) {
 925		if (i == colonpos) {
 926			if (needcolon || i == 0)
 927				*p++ = ':';
 928			*p++ = ':';
 929			needcolon = false;
 930			i += longest - 1;
 931			continue;
 932		}
 933		if (needcolon) {
 934			*p++ = ':';
 935			needcolon = false;
 936		}
 937		/* hex u16 without leading 0s */
 938		word = ntohs(in6.s6_addr16[i]);
 939		hi = word >> 8;
 940		lo = word & 0xff;
 941		if (hi) {
 942			if (hi > 0x0f)
 943				p = hex_byte_pack(p, hi);
 944			else
 945				*p++ = hex_asc_lo(hi);
 946			p = hex_byte_pack(p, lo);
 947		}
 948		else if (lo > 0x0f)
 949			p = hex_byte_pack(p, lo);
 950		else
 951			*p++ = hex_asc_lo(lo);
 952		needcolon = true;
 953	}
 954
 955	if (useIPv4) {
 956		if (needcolon)
 957			*p++ = ':';
 958		p = ip4_string(p, &in6.s6_addr[12], "I4");
 959	}
 960	*p = '\0';
 961
 962	return p;
 963}
 964
 965static noinline_for_stack
 966char *ip6_string(char *p, const char *addr, const char *fmt)
 967{
 968	int i;
 969
 970	for (i = 0; i < 8; i++) {
 971		p = hex_byte_pack(p, *addr++);
 972		p = hex_byte_pack(p, *addr++);
 973		if (fmt[0] == 'I' && i != 7)
 974			*p++ = ':';
 975	}
 976	*p = '\0';
 977
 978	return p;
 979}
 980
 981static noinline_for_stack
 982char *ip6_addr_string(char *buf, char *end, const u8 *addr,
 983		      struct printf_spec spec, const char *fmt)
 984{
 985	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
 986
 987	if (fmt[0] == 'I' && fmt[2] == 'c')
 988		ip6_compressed_string(ip6_addr, addr);
 989	else
 990		ip6_string(ip6_addr, addr, fmt);
 991
 992	return string(buf, end, ip6_addr, spec);
 993}
 994
 995static noinline_for_stack
 996char *ip4_addr_string(char *buf, char *end, const u8 *addr,
 997		      struct printf_spec spec, const char *fmt)
 998{
 999	char ip4_addr[sizeof("255.255.255.255")];
1000
1001	ip4_string(ip4_addr, addr, fmt);
1002
1003	return string(buf, end, ip4_addr, spec);
1004}
1005
1006static noinline_for_stack
1007char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1008			 struct printf_spec spec, const char *fmt)
1009{
1010	bool have_p = false, have_s = false, have_f = false, have_c = false;
1011	char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1012		      sizeof(":12345") + sizeof("/123456789") +
1013		      sizeof("%1234567890")];
1014	char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1015	const u8 *addr = (const u8 *) &sa->sin6_addr;
1016	char fmt6[2] = { fmt[0], '6' };
1017	u8 off = 0;
1018
1019	fmt++;
1020	while (isalpha(*++fmt)) {
1021		switch (*fmt) {
1022		case 'p':
1023			have_p = true;
1024			break;
1025		case 'f':
1026			have_f = true;
1027			break;
1028		case 's':
1029			have_s = true;
1030			break;
1031		case 'c':
1032			have_c = true;
1033			break;
1034		}
1035	}
1036
1037	if (have_p || have_s || have_f) {
1038		*p = '[';
1039		off = 1;
1040	}
1041
1042	if (fmt6[0] == 'I' && have_c)
1043		p = ip6_compressed_string(ip6_addr + off, addr);
1044	else
1045		p = ip6_string(ip6_addr + off, addr, fmt6);
1046
1047	if (have_p || have_s || have_f)
1048		*p++ = ']';
1049
1050	if (have_p) {
1051		*p++ = ':';
1052		p = number(p, pend, ntohs(sa->sin6_port), spec);
1053	}
1054	if (have_f) {
1055		*p++ = '/';
1056		p = number(p, pend, ntohl(sa->sin6_flowinfo &
1057					  IPV6_FLOWINFO_MASK), spec);
1058	}
1059	if (have_s) {
1060		*p++ = '%';
1061		p = number(p, pend, sa->sin6_scope_id, spec);
1062	}
1063	*p = '\0';
1064
1065	return string(buf, end, ip6_addr, spec);
1066}
1067
1068static noinline_for_stack
1069char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1070			 struct printf_spec spec, const char *fmt)
1071{
1072	bool have_p = false;
1073	char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1074	char *pend = ip4_addr + sizeof(ip4_addr);
1075	const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1076	char fmt4[3] = { fmt[0], '4', 0 };
1077
1078	fmt++;
1079	while (isalpha(*++fmt)) {
1080		switch (*fmt) {
1081		case 'p':
1082			have_p = true;
1083			break;
1084		case 'h':
1085		case 'l':
1086		case 'n':
1087		case 'b':
1088			fmt4[2] = *fmt;
1089			break;
1090		}
1091	}
1092
1093	p = ip4_string(ip4_addr, addr, fmt4);
1094	if (have_p) {
1095		*p++ = ':';
1096		p = number(p, pend, ntohs(sa->sin_port), spec);
1097	}
1098	*p = '\0';
1099
1100	return string(buf, end, ip4_addr, spec);
1101}
1102
1103static noinline_for_stack
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1104char *uuid_string(char *buf, char *end, const u8 *addr,
1105		  struct printf_spec spec, const char *fmt)
1106{
1107	char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1108	char *p = uuid;
1109	int i;
1110	static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1111	static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1112	const u8 *index = be;
1113	bool uc = false;
1114
1115	switch (*(++fmt)) {
1116	case 'L':
1117		uc = true;		/* fall-through */
1118	case 'l':
1119		index = le;
1120		break;
1121	case 'B':
1122		uc = true;
1123		break;
1124	}
1125
1126	for (i = 0; i < 16; i++) {
1127		p = hex_byte_pack(p, addr[index[i]]);
 
 
 
1128		switch (i) {
1129		case 3:
1130		case 5:
1131		case 7:
1132		case 9:
1133			*p++ = '-';
1134			break;
1135		}
1136	}
1137
1138	*p = 0;
1139
1140	if (uc) {
1141		p = uuid;
1142		do {
1143			*p = toupper(*p);
1144		} while (*(++p));
1145	}
1146
1147	return string(buf, end, uuid, spec);
1148}
1149
1150static
1151char *netdev_feature_string(char *buf, char *end, const u8 *addr,
1152		      struct printf_spec spec)
1153{
1154	spec.flags |= SPECIAL | SMALL | ZEROPAD;
1155	if (spec.field_width == -1)
1156		spec.field_width = 2 + 2 * sizeof(netdev_features_t);
1157	spec.base = 16;
1158
1159	return number(buf, end, *(const netdev_features_t *)addr, spec);
 
 
 
 
 
 
 
 
 
 
 
1160}
1161
1162static noinline_for_stack
1163char *address_val(char *buf, char *end, const void *addr,
1164		  struct printf_spec spec, const char *fmt)
1165{
1166	unsigned long long num;
1167
1168	spec.flags |= SPECIAL | SMALL | ZEROPAD;
1169	spec.base = 16;
1170
1171	switch (fmt[1]) {
1172	case 'd':
1173		num = *(const dma_addr_t *)addr;
1174		spec.field_width = sizeof(dma_addr_t) * 2 + 2;
1175		break;
1176	case 'p':
1177	default:
1178		num = *(const phys_addr_t *)addr;
1179		spec.field_width = sizeof(phys_addr_t) * 2 + 2;
1180		break;
1181	}
1182
1183	return number(buf, end, num, spec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1184}
1185
1186int kptr_restrict __read_mostly;
1187
1188/*
1189 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1190 * by an extra set of alphanumeric characters that are extended format
1191 * specifiers.
1192 *
1193 * Right now we handle:
1194 *
1195 * - 'F' For symbolic function descriptor pointers with offset
1196 * - 'f' For simple symbolic function names without offset
1197 * - 'S' For symbolic direct pointers with offset
1198 * - 's' For symbolic direct pointers without offset
1199 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1200 * - 'B' For backtraced symbolic direct pointers with offset
1201 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1202 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
 
 
 
 
1203 * - 'M' For a 6-byte MAC address, it prints the address in the
1204 *       usual colon-separated hex notation
1205 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1206 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1207 *       with a dash-separated hex notation
1208 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1209 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1210 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1211 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1212 *       [S][pfs]
1213 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1214 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1215 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1216 *       IPv6 omits the colons (01020304...0f)
1217 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1218 *       [S][pfs]
1219 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1220 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1221 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1222 * - 'I[6S]c' for IPv6 addresses printed as specified by
1223 *       http://tools.ietf.org/html/rfc5952
 
 
 
 
 
 
 
 
 
 
 
1224 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1225 *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1226 *       Options for %pU are:
1227 *         b big endian lower case hex (default)
1228 *         B big endian UPPER case hex
1229 *         l little endian lower case hex
1230 *         L little endian UPPER case hex
1231 *           big endian output byte order is:
1232 *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1233 *           little endian output byte order is:
1234 *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1235 * - 'V' For a struct va_format which contains a format string * and va_list *,
1236 *       call vsnprintf(->format, *->va_list).
1237 *       Implements a "recursive vsnprintf".
1238 *       Do not use this feature without some mechanism to verify the
1239 *       correctness of the format string and va_list arguments.
1240 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1241 * - 'NF' For a netdev_features_t
1242 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1243 *            a certain separator (' ' by default):
1244 *              C colon
1245 *              D dash
1246 *              N no separator
1247 *            The maximum supported length is 64 bytes of the input. Consider
1248 *            to use print_hex_dump() for the larger input.
1249 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1250 *           (default assumed to be phys_addr_t, passed by reference)
1251 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1252 * - 'D[234]' Same as 'd' but for a struct file
 
 
 
 
 
 
 
 
 
 
 
 
 
1253 *
1254 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1255 * function pointers are really function descriptors, which contain a
1256 * pointer to the real address.
1257 */
1258static noinline_for_stack
1259char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1260	      struct printf_spec spec)
1261{
1262	int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
1263
1264	if (!ptr && *fmt != 'K') {
1265		/*
1266		 * Print (null) with the same width as a pointer so it makes
1267		 * tabular output look nice.
1268		 */
1269		if (spec.field_width == -1)
1270			spec.field_width = default_width;
1271		return string(buf, end, "(null)", spec);
1272	}
1273
1274	switch (*fmt) {
1275	case 'F':
1276	case 'f':
1277		ptr = dereference_function_descriptor(ptr);
1278		/* Fallthrough */
1279	case 'S':
1280	case 's':
1281	case 'B':
1282		return symbol_string(buf, end, ptr, spec, fmt);
1283	case 'R':
1284	case 'r':
1285		return resource_string(buf, end, ptr, spec, fmt);
1286	case 'h':
1287		return hex_string(buf, end, ptr, spec, fmt);
 
 
 
 
 
 
 
1288	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
1289	case 'm':			/* Contiguous: 000102030405 */
1290					/* [mM]F (FDDI) */
1291					/* [mM]R (Reverse order; Bluetooth) */
1292		return mac_address_string(buf, end, ptr, spec, fmt);
1293	case 'I':			/* Formatted IP supported
1294					 * 4:	1.2.3.4
1295					 * 6:	0001:0203:...:0708
1296					 * 6c:	1::708 or 1::1.2.3.4
1297					 */
1298	case 'i':			/* Contiguous:
1299					 * 4:	001.002.003.004
1300					 * 6:   000102...0f
1301					 */
1302		switch (fmt[1]) {
1303		case '6':
1304			return ip6_addr_string(buf, end, ptr, spec, fmt);
1305		case '4':
1306			return ip4_addr_string(buf, end, ptr, spec, fmt);
1307		case 'S': {
1308			const union {
1309				struct sockaddr		raw;
1310				struct sockaddr_in	v4;
1311				struct sockaddr_in6	v6;
1312			} *sa = ptr;
1313
1314			switch (sa->raw.sa_family) {
1315			case AF_INET:
1316				return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1317			case AF_INET6:
1318				return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1319			default:
1320				return string(buf, end, "(invalid address)", spec);
1321			}}
1322		}
1323		break;
 
 
1324	case 'U':
1325		return uuid_string(buf, end, ptr, spec, fmt);
1326	case 'V':
1327		{
1328			va_list va;
1329
1330			va_copy(va, *((struct va_format *)ptr)->va);
1331			buf += vsnprintf(buf, end > buf ? end - buf : 0,
1332					 ((struct va_format *)ptr)->fmt, va);
1333			va_end(va);
1334			return buf;
1335		}
1336	case 'K':
1337		/*
1338		 * %pK cannot be used in IRQ context because its test
1339		 * for CAP_SYSLOG would be meaningless.
1340		 */
1341		if (kptr_restrict && (in_irq() || in_serving_softirq() ||
1342				      in_nmi())) {
1343			if (spec.field_width == -1)
1344				spec.field_width = default_width;
1345			return string(buf, end, "pK-error", spec);
1346		}
1347
1348		switch (kptr_restrict) {
1349		case 0:
1350			/* Always print %pK values */
1351			break;
1352		case 1: {
 
 
 
 
 
 
 
 
 
 
 
 
1353			/*
1354			 * Only print the real pointer value if the current
1355			 * process has CAP_SYSLOG and is running with the
1356			 * same credentials it started with. This is because
1357			 * access to files is checked at open() time, but %pK
1358			 * checks permission at read() time. We don't want to
1359			 * leak pointer values if a binary opens a file using
1360			 * %pK and then elevates privileges before reading it.
1361			 */
1362			const struct cred *cred = current_cred();
1363
1364			if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1365			    !uid_eq(cred->euid, cred->uid) ||
1366			    !gid_eq(cred->egid, cred->gid))
1367				ptr = NULL;
1368			break;
1369		}
1370		case 2:
1371		default:
1372			/* Always print 0's for %pK */
1373			ptr = NULL;
1374			break;
1375		}
1376		break;
1377
1378	case 'N':
1379		switch (fmt[1]) {
1380		case 'F':
1381			return netdev_feature_string(buf, end, ptr, spec);
1382		}
1383		break;
1384	case 'a':
1385		return address_val(buf, end, ptr, spec, fmt);
1386	case 'd':
1387		return dentry_name(buf, end, ptr, spec, fmt);
 
 
1388	case 'D':
1389		return dentry_name(buf, end,
1390				   ((const struct file *)ptr)->f_path.dentry,
1391				   spec, fmt);
 
 
 
 
 
 
 
1392	}
1393	spec.flags |= SMALL;
1394	if (spec.field_width == -1) {
1395		spec.field_width = default_width;
1396		spec.flags |= ZEROPAD;
1397	}
1398	spec.base = 16;
1399
1400	return number(buf, end, (unsigned long) ptr, spec);
1401}
1402
1403/*
1404 * Helper function to decode printf style format.
1405 * Each call decode a token from the format and return the
1406 * number of characters read (or likely the delta where it wants
1407 * to go on the next call).
1408 * The decoded token is returned through the parameters
1409 *
1410 * 'h', 'l', or 'L' for integer fields
1411 * 'z' support added 23/7/1999 S.H.
1412 * 'z' changed to 'Z' --davidm 1/25/99
1413 * 't' added for ptrdiff_t
1414 *
1415 * @fmt: the format string
1416 * @type of the token returned
1417 * @flags: various flags such as +, -, # tokens..
1418 * @field_width: overwritten width
1419 * @base: base of the number (octal, hex, ...)
1420 * @precision: precision of a number
1421 * @qualifier: qualifier of a number (long, size_t, ...)
1422 */
1423static noinline_for_stack
1424int format_decode(const char *fmt, struct printf_spec *spec)
1425{
1426	const char *start = fmt;
 
1427
1428	/* we finished early by reading the field width */
1429	if (spec->type == FORMAT_TYPE_WIDTH) {
1430		if (spec->field_width < 0) {
1431			spec->field_width = -spec->field_width;
1432			spec->flags |= LEFT;
1433		}
1434		spec->type = FORMAT_TYPE_NONE;
1435		goto precision;
1436	}
1437
1438	/* we finished early by reading the precision */
1439	if (spec->type == FORMAT_TYPE_PRECISION) {
1440		if (spec->precision < 0)
1441			spec->precision = 0;
1442
1443		spec->type = FORMAT_TYPE_NONE;
1444		goto qualifier;
1445	}
1446
1447	/* By default */
1448	spec->type = FORMAT_TYPE_NONE;
1449
1450	for (; *fmt ; ++fmt) {
1451		if (*fmt == '%')
1452			break;
1453	}
1454
1455	/* Return the current non-format string */
1456	if (fmt != start || !*fmt)
1457		return fmt - start;
1458
1459	/* Process flags */
1460	spec->flags = 0;
1461
1462	while (1) { /* this also skips first '%' */
1463		bool found = true;
1464
1465		++fmt;
1466
1467		switch (*fmt) {
1468		case '-': spec->flags |= LEFT;    break;
1469		case '+': spec->flags |= PLUS;    break;
1470		case ' ': spec->flags |= SPACE;   break;
1471		case '#': spec->flags |= SPECIAL; break;
1472		case '0': spec->flags |= ZEROPAD; break;
1473		default:  found = false;
1474		}
1475
1476		if (!found)
1477			break;
1478	}
1479
1480	/* get field width */
1481	spec->field_width = -1;
1482
1483	if (isdigit(*fmt))
1484		spec->field_width = skip_atoi(&fmt);
1485	else if (*fmt == '*') {
1486		/* it's the next argument */
1487		spec->type = FORMAT_TYPE_WIDTH;
1488		return ++fmt - start;
1489	}
1490
1491precision:
1492	/* get the precision */
1493	spec->precision = -1;
1494	if (*fmt == '.') {
1495		++fmt;
1496		if (isdigit(*fmt)) {
1497			spec->precision = skip_atoi(&fmt);
1498			if (spec->precision < 0)
1499				spec->precision = 0;
1500		} else if (*fmt == '*') {
1501			/* it's the next argument */
1502			spec->type = FORMAT_TYPE_PRECISION;
1503			return ++fmt - start;
1504		}
1505	}
1506
1507qualifier:
1508	/* get the conversion qualifier */
1509	spec->qualifier = -1;
1510	if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1511	    _tolower(*fmt) == 'z' || *fmt == 't') {
1512		spec->qualifier = *fmt++;
1513		if (unlikely(spec->qualifier == *fmt)) {
1514			if (spec->qualifier == 'l') {
1515				spec->qualifier = 'L';
1516				++fmt;
1517			} else if (spec->qualifier == 'h') {
1518				spec->qualifier = 'H';
1519				++fmt;
1520			}
1521		}
1522	}
1523
1524	/* default base */
1525	spec->base = 10;
1526	switch (*fmt) {
1527	case 'c':
1528		spec->type = FORMAT_TYPE_CHAR;
1529		return ++fmt - start;
1530
1531	case 's':
1532		spec->type = FORMAT_TYPE_STR;
1533		return ++fmt - start;
1534
1535	case 'p':
1536		spec->type = FORMAT_TYPE_PTR;
1537		return fmt - start;
1538		/* skip alnum */
1539
1540	case '%':
1541		spec->type = FORMAT_TYPE_PERCENT_CHAR;
1542		return ++fmt - start;
1543
1544	/* integer number formats - set up the flags and "break" */
1545	case 'o':
1546		spec->base = 8;
1547		break;
1548
1549	case 'x':
1550		spec->flags |= SMALL;
1551
1552	case 'X':
1553		spec->base = 16;
1554		break;
1555
1556	case 'd':
1557	case 'i':
1558		spec->flags |= SIGN;
1559	case 'u':
1560		break;
1561
1562	case 'n':
1563		/*
1564		 * Since %n poses a greater security risk than utility, treat
1565		 * it as an invalid format specifier. Warn about its use so
1566		 * that new instances don't get added.
1567		 */
1568		WARN_ONCE(1, "Please remove ignored %%n in '%s'\n", fmt);
1569		/* Fall-through */
1570
1571	default:
 
1572		spec->type = FORMAT_TYPE_INVALID;
1573		return fmt - start;
1574	}
1575
1576	if (spec->qualifier == 'L')
1577		spec->type = FORMAT_TYPE_LONG_LONG;
1578	else if (spec->qualifier == 'l') {
1579		if (spec->flags & SIGN)
1580			spec->type = FORMAT_TYPE_LONG;
1581		else
1582			spec->type = FORMAT_TYPE_ULONG;
1583	} else if (_tolower(spec->qualifier) == 'z') {
1584		spec->type = FORMAT_TYPE_SIZE_T;
1585	} else if (spec->qualifier == 't') {
1586		spec->type = FORMAT_TYPE_PTRDIFF;
1587	} else if (spec->qualifier == 'H') {
1588		if (spec->flags & SIGN)
1589			spec->type = FORMAT_TYPE_BYTE;
1590		else
1591			spec->type = FORMAT_TYPE_UBYTE;
1592	} else if (spec->qualifier == 'h') {
1593		if (spec->flags & SIGN)
1594			spec->type = FORMAT_TYPE_SHORT;
1595		else
1596			spec->type = FORMAT_TYPE_USHORT;
1597	} else {
1598		if (spec->flags & SIGN)
1599			spec->type = FORMAT_TYPE_INT;
1600		else
1601			spec->type = FORMAT_TYPE_UINT;
1602	}
1603
1604	return ++fmt - start;
1605}
1606
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1607/**
1608 * vsnprintf - Format a string and place it in a buffer
1609 * @buf: The buffer to place the result into
1610 * @size: The size of the buffer, including the trailing null space
1611 * @fmt: The format string to use
1612 * @args: Arguments for the format string
1613 *
1614 * This function follows C99 vsnprintf, but has some extensions:
1615 * %pS output the name of a text symbol with offset
1616 * %ps output the name of a text symbol without offset
1617 * %pF output the name of a function pointer with its offset
1618 * %pf output the name of a function pointer without its offset
1619 * %pB output the name of a backtrace symbol with its offset
1620 * %pR output the address range in a struct resource with decoded flags
1621 * %pr output the address range in a struct resource with raw flags
1622 * %pM output a 6-byte MAC address with colons
1623 * %pMR output a 6-byte MAC address with colons in reversed order
1624 * %pMF output a 6-byte MAC address with dashes
1625 * %pm output a 6-byte MAC address without colons
1626 * %pmR output a 6-byte MAC address without colons in reversed order
1627 * %pI4 print an IPv4 address without leading zeros
1628 * %pi4 print an IPv4 address with leading zeros
1629 * %pI6 print an IPv6 address with colons
1630 * %pi6 print an IPv6 address without colons
1631 * %pI6c print an IPv6 address as specified by RFC 5952
1632 * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1633 * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1634 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1635 *   case.
1636 * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1637 *           bytes of the input)
1638 * %n is ignored
1639 *
1640 * ** Please update Documentation/printk-formats.txt when making changes **
 
 
 
 
 
 
1641 *
1642 * The return value is the number of characters which would
1643 * be generated for the given input, excluding the trailing
1644 * '\0', as per ISO C99. If you want to have the exact
1645 * number of characters written into @buf as return value
1646 * (not including the trailing '\0'), use vscnprintf(). If the
1647 * return is greater than or equal to @size, the resulting
1648 * string is truncated.
1649 *
1650 * If you're not already dealing with a va_list consider using snprintf().
1651 */
1652int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1653{
1654	unsigned long long num;
1655	char *str, *end;
1656	struct printf_spec spec = {0};
1657
1658	/* Reject out-of-range values early.  Large positive sizes are
1659	   used for unknown buffer sizes. */
1660	if (WARN_ON_ONCE((int) size < 0))
1661		return 0;
1662
1663	str = buf;
1664	end = buf + size;
1665
1666	/* Make sure end is always >= buf */
1667	if (end < buf) {
1668		end = ((void *)-1);
1669		size = end - buf;
1670	}
1671
1672	while (*fmt) {
1673		const char *old_fmt = fmt;
1674		int read = format_decode(fmt, &spec);
1675
1676		fmt += read;
1677
1678		switch (spec.type) {
1679		case FORMAT_TYPE_NONE: {
1680			int copy = read;
1681			if (str < end) {
1682				if (copy > end - str)
1683					copy = end - str;
1684				memcpy(str, old_fmt, copy);
1685			}
1686			str += read;
1687			break;
1688		}
1689
1690		case FORMAT_TYPE_WIDTH:
1691			spec.field_width = va_arg(args, int);
1692			break;
1693
1694		case FORMAT_TYPE_PRECISION:
1695			spec.precision = va_arg(args, int);
1696			break;
1697
1698		case FORMAT_TYPE_CHAR: {
1699			char c;
1700
1701			if (!(spec.flags & LEFT)) {
1702				while (--spec.field_width > 0) {
1703					if (str < end)
1704						*str = ' ';
1705					++str;
1706
1707				}
1708			}
1709			c = (unsigned char) va_arg(args, int);
1710			if (str < end)
1711				*str = c;
1712			++str;
1713			while (--spec.field_width > 0) {
1714				if (str < end)
1715					*str = ' ';
1716				++str;
1717			}
1718			break;
1719		}
1720
1721		case FORMAT_TYPE_STR:
1722			str = string(str, end, va_arg(args, char *), spec);
1723			break;
1724
1725		case FORMAT_TYPE_PTR:
1726			str = pointer(fmt+1, str, end, va_arg(args, void *),
1727				      spec);
1728			while (isalnum(*fmt))
1729				fmt++;
1730			break;
1731
1732		case FORMAT_TYPE_PERCENT_CHAR:
1733			if (str < end)
1734				*str = '%';
1735			++str;
1736			break;
1737
1738		case FORMAT_TYPE_INVALID:
1739			if (str < end)
1740				*str = '%';
1741			++str;
1742			break;
 
 
 
 
 
1743
1744		default:
1745			switch (spec.type) {
1746			case FORMAT_TYPE_LONG_LONG:
1747				num = va_arg(args, long long);
1748				break;
1749			case FORMAT_TYPE_ULONG:
1750				num = va_arg(args, unsigned long);
1751				break;
1752			case FORMAT_TYPE_LONG:
1753				num = va_arg(args, long);
1754				break;
1755			case FORMAT_TYPE_SIZE_T:
1756				if (spec.flags & SIGN)
1757					num = va_arg(args, ssize_t);
1758				else
1759					num = va_arg(args, size_t);
1760				break;
1761			case FORMAT_TYPE_PTRDIFF:
1762				num = va_arg(args, ptrdiff_t);
1763				break;
1764			case FORMAT_TYPE_UBYTE:
1765				num = (unsigned char) va_arg(args, int);
1766				break;
1767			case FORMAT_TYPE_BYTE:
1768				num = (signed char) va_arg(args, int);
1769				break;
1770			case FORMAT_TYPE_USHORT:
1771				num = (unsigned short) va_arg(args, int);
1772				break;
1773			case FORMAT_TYPE_SHORT:
1774				num = (short) va_arg(args, int);
1775				break;
1776			case FORMAT_TYPE_INT:
1777				num = (int) va_arg(args, int);
1778				break;
1779			default:
1780				num = va_arg(args, unsigned int);
1781			}
1782
1783			str = number(str, end, num, spec);
1784		}
1785	}
1786
 
1787	if (size > 0) {
1788		if (str < end)
1789			*str = '\0';
1790		else
1791			end[-1] = '\0';
1792	}
1793
1794	/* the trailing null byte doesn't count towards the total */
1795	return str-buf;
1796
1797}
1798EXPORT_SYMBOL(vsnprintf);
1799
1800/**
1801 * vscnprintf - Format a string and place it in a buffer
1802 * @buf: The buffer to place the result into
1803 * @size: The size of the buffer, including the trailing null space
1804 * @fmt: The format string to use
1805 * @args: Arguments for the format string
1806 *
1807 * The return value is the number of characters which have been written into
1808 * the @buf not including the trailing '\0'. If @size is == 0 the function
1809 * returns 0.
1810 *
1811 * If you're not already dealing with a va_list consider using scnprintf().
1812 *
1813 * See the vsnprintf() documentation for format string extensions over C99.
1814 */
1815int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1816{
1817	int i;
1818
1819	i = vsnprintf(buf, size, fmt, args);
1820
1821	if (likely(i < size))
1822		return i;
1823	if (size != 0)
1824		return size - 1;
1825	return 0;
1826}
1827EXPORT_SYMBOL(vscnprintf);
1828
1829/**
1830 * snprintf - Format a string and place it in a buffer
1831 * @buf: The buffer to place the result into
1832 * @size: The size of the buffer, including the trailing null space
1833 * @fmt: The format string to use
1834 * @...: Arguments for the format string
1835 *
1836 * The return value is the number of characters which would be
1837 * generated for the given input, excluding the trailing null,
1838 * as per ISO C99.  If the return is greater than or equal to
1839 * @size, the resulting string is truncated.
1840 *
1841 * See the vsnprintf() documentation for format string extensions over C99.
1842 */
1843int snprintf(char *buf, size_t size, const char *fmt, ...)
1844{
1845	va_list args;
1846	int i;
1847
1848	va_start(args, fmt);
1849	i = vsnprintf(buf, size, fmt, args);
1850	va_end(args);
1851
1852	return i;
1853}
1854EXPORT_SYMBOL(snprintf);
1855
1856/**
1857 * scnprintf - Format a string and place it in a buffer
1858 * @buf: The buffer to place the result into
1859 * @size: The size of the buffer, including the trailing null space
1860 * @fmt: The format string to use
1861 * @...: Arguments for the format string
1862 *
1863 * The return value is the number of characters written into @buf not including
1864 * the trailing '\0'. If @size is == 0 the function returns 0.
1865 */
1866
1867int scnprintf(char *buf, size_t size, const char *fmt, ...)
1868{
1869	va_list args;
1870	int i;
1871
1872	va_start(args, fmt);
1873	i = vscnprintf(buf, size, fmt, args);
1874	va_end(args);
1875
1876	return i;
1877}
1878EXPORT_SYMBOL(scnprintf);
1879
1880/**
1881 * vsprintf - Format a string and place it in a buffer
1882 * @buf: The buffer to place the result into
1883 * @fmt: The format string to use
1884 * @args: Arguments for the format string
1885 *
1886 * The function returns the number of characters written
1887 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1888 * buffer overflows.
1889 *
1890 * If you're not already dealing with a va_list consider using sprintf().
1891 *
1892 * See the vsnprintf() documentation for format string extensions over C99.
1893 */
1894int vsprintf(char *buf, const char *fmt, va_list args)
1895{
1896	return vsnprintf(buf, INT_MAX, fmt, args);
1897}
1898EXPORT_SYMBOL(vsprintf);
1899
1900/**
1901 * sprintf - Format a string and place it in a buffer
1902 * @buf: The buffer to place the result into
1903 * @fmt: The format string to use
1904 * @...: Arguments for the format string
1905 *
1906 * The function returns the number of characters written
1907 * into @buf. Use snprintf() or scnprintf() in order to avoid
1908 * buffer overflows.
1909 *
1910 * See the vsnprintf() documentation for format string extensions over C99.
1911 */
1912int sprintf(char *buf, const char *fmt, ...)
1913{
1914	va_list args;
1915	int i;
1916
1917	va_start(args, fmt);
1918	i = vsnprintf(buf, INT_MAX, fmt, args);
1919	va_end(args);
1920
1921	return i;
1922}
1923EXPORT_SYMBOL(sprintf);
1924
1925#ifdef CONFIG_BINARY_PRINTF
1926/*
1927 * bprintf service:
1928 * vbin_printf() - VA arguments to binary data
1929 * bstr_printf() - Binary data to text string
1930 */
1931
1932/**
1933 * vbin_printf - Parse a format string and place args' binary value in a buffer
1934 * @bin_buf: The buffer to place args' binary value
1935 * @size: The size of the buffer(by words(32bits), not characters)
1936 * @fmt: The format string to use
1937 * @args: Arguments for the format string
1938 *
1939 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1940 * is skiped.
1941 *
1942 * The return value is the number of words(32bits) which would be generated for
1943 * the given input.
1944 *
1945 * NOTE:
1946 * If the return value is greater than @size, the resulting bin_buf is NOT
1947 * valid for bstr_printf().
1948 */
1949int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1950{
1951	struct printf_spec spec = {0};
1952	char *str, *end;
1953
1954	str = (char *)bin_buf;
1955	end = (char *)(bin_buf + size);
1956
1957#define save_arg(type)							\
1958do {									\
1959	if (sizeof(type) == 8) {					\
1960		unsigned long long value;				\
1961		str = PTR_ALIGN(str, sizeof(u32));			\
1962		value = va_arg(args, unsigned long long);		\
1963		if (str + sizeof(type) <= end) {			\
1964			*(u32 *)str = *(u32 *)&value;			\
1965			*(u32 *)(str + 4) = *((u32 *)&value + 1);	\
1966		}							\
1967	} else {							\
1968		unsigned long value;					\
1969		str = PTR_ALIGN(str, sizeof(type));			\
1970		value = va_arg(args, int);				\
1971		if (str + sizeof(type) <= end)				\
1972			*(typeof(type) *)str = (type)value;		\
1973	}								\
1974	str += sizeof(type);						\
1975} while (0)
1976
1977	while (*fmt) {
1978		int read = format_decode(fmt, &spec);
1979
1980		fmt += read;
1981
1982		switch (spec.type) {
1983		case FORMAT_TYPE_NONE:
1984		case FORMAT_TYPE_INVALID:
1985		case FORMAT_TYPE_PERCENT_CHAR:
1986			break;
 
 
1987
1988		case FORMAT_TYPE_WIDTH:
1989		case FORMAT_TYPE_PRECISION:
1990			save_arg(int);
1991			break;
1992
1993		case FORMAT_TYPE_CHAR:
1994			save_arg(char);
1995			break;
1996
1997		case FORMAT_TYPE_STR: {
1998			const char *save_str = va_arg(args, char *);
1999			size_t len;
2000
2001			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2002					|| (unsigned long)save_str < PAGE_SIZE)
2003				save_str = "(null)";
2004			len = strlen(save_str) + 1;
2005			if (str + len < end)
2006				memcpy(str, save_str, len);
2007			str += len;
2008			break;
2009		}
2010
2011		case FORMAT_TYPE_PTR:
2012			save_arg(void *);
2013			/* skip all alphanumeric pointer suffixes */
2014			while (isalnum(*fmt))
2015				fmt++;
2016			break;
2017
2018		default:
2019			switch (spec.type) {
2020
2021			case FORMAT_TYPE_LONG_LONG:
2022				save_arg(long long);
2023				break;
2024			case FORMAT_TYPE_ULONG:
2025			case FORMAT_TYPE_LONG:
2026				save_arg(unsigned long);
2027				break;
2028			case FORMAT_TYPE_SIZE_T:
2029				save_arg(size_t);
2030				break;
2031			case FORMAT_TYPE_PTRDIFF:
2032				save_arg(ptrdiff_t);
2033				break;
2034			case FORMAT_TYPE_UBYTE:
2035			case FORMAT_TYPE_BYTE:
2036				save_arg(char);
2037				break;
2038			case FORMAT_TYPE_USHORT:
2039			case FORMAT_TYPE_SHORT:
2040				save_arg(short);
2041				break;
2042			default:
2043				save_arg(int);
2044			}
2045		}
2046	}
2047
 
2048	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2049#undef save_arg
2050}
2051EXPORT_SYMBOL_GPL(vbin_printf);
2052
2053/**
2054 * bstr_printf - Format a string from binary arguments and place it in a buffer
2055 * @buf: The buffer to place the result into
2056 * @size: The size of the buffer, including the trailing null space
2057 * @fmt: The format string to use
2058 * @bin_buf: Binary arguments for the format string
2059 *
2060 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2061 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2062 * a binary buffer that generated by vbin_printf.
2063 *
2064 * The format follows C99 vsnprintf, but has some extensions:
2065 *  see vsnprintf comment for details.
2066 *
2067 * The return value is the number of characters which would
2068 * be generated for the given input, excluding the trailing
2069 * '\0', as per ISO C99. If you want to have the exact
2070 * number of characters written into @buf as return value
2071 * (not including the trailing '\0'), use vscnprintf(). If the
2072 * return is greater than or equal to @size, the resulting
2073 * string is truncated.
2074 */
2075int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2076{
2077	struct printf_spec spec = {0};
2078	char *str, *end;
2079	const char *args = (const char *)bin_buf;
2080
2081	if (WARN_ON_ONCE((int) size < 0))
2082		return 0;
2083
2084	str = buf;
2085	end = buf + size;
2086
2087#define get_arg(type)							\
2088({									\
2089	typeof(type) value;						\
2090	if (sizeof(type) == 8) {					\
2091		args = PTR_ALIGN(args, sizeof(u32));			\
2092		*(u32 *)&value = *(u32 *)args;				\
2093		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
2094	} else {							\
2095		args = PTR_ALIGN(args, sizeof(type));			\
2096		value = *(typeof(type) *)args;				\
2097	}								\
2098	args += sizeof(type);						\
2099	value;								\
2100})
2101
2102	/* Make sure end is always >= buf */
2103	if (end < buf) {
2104		end = ((void *)-1);
2105		size = end - buf;
2106	}
2107
2108	while (*fmt) {
2109		const char *old_fmt = fmt;
2110		int read = format_decode(fmt, &spec);
2111
2112		fmt += read;
2113
2114		switch (spec.type) {
2115		case FORMAT_TYPE_NONE: {
2116			int copy = read;
2117			if (str < end) {
2118				if (copy > end - str)
2119					copy = end - str;
2120				memcpy(str, old_fmt, copy);
2121			}
2122			str += read;
2123			break;
2124		}
2125
2126		case FORMAT_TYPE_WIDTH:
2127			spec.field_width = get_arg(int);
2128			break;
2129
2130		case FORMAT_TYPE_PRECISION:
2131			spec.precision = get_arg(int);
2132			break;
2133
2134		case FORMAT_TYPE_CHAR: {
2135			char c;
2136
2137			if (!(spec.flags & LEFT)) {
2138				while (--spec.field_width > 0) {
2139					if (str < end)
2140						*str = ' ';
2141					++str;
2142				}
2143			}
2144			c = (unsigned char) get_arg(char);
2145			if (str < end)
2146				*str = c;
2147			++str;
2148			while (--spec.field_width > 0) {
2149				if (str < end)
2150					*str = ' ';
2151				++str;
2152			}
2153			break;
2154		}
2155
2156		case FORMAT_TYPE_STR: {
2157			const char *str_arg = args;
2158			args += strlen(str_arg) + 1;
2159			str = string(str, end, (char *)str_arg, spec);
2160			break;
2161		}
2162
2163		case FORMAT_TYPE_PTR:
2164			str = pointer(fmt+1, str, end, get_arg(void *), spec);
2165			while (isalnum(*fmt))
2166				fmt++;
2167			break;
2168
2169		case FORMAT_TYPE_PERCENT_CHAR:
2170		case FORMAT_TYPE_INVALID:
2171			if (str < end)
2172				*str = '%';
2173			++str;
2174			break;
2175
 
 
 
2176		default: {
2177			unsigned long long num;
2178
2179			switch (spec.type) {
2180
2181			case FORMAT_TYPE_LONG_LONG:
2182				num = get_arg(long long);
2183				break;
2184			case FORMAT_TYPE_ULONG:
2185			case FORMAT_TYPE_LONG:
2186				num = get_arg(unsigned long);
2187				break;
2188			case FORMAT_TYPE_SIZE_T:
2189				num = get_arg(size_t);
2190				break;
2191			case FORMAT_TYPE_PTRDIFF:
2192				num = get_arg(ptrdiff_t);
2193				break;
2194			case FORMAT_TYPE_UBYTE:
2195				num = get_arg(unsigned char);
2196				break;
2197			case FORMAT_TYPE_BYTE:
2198				num = get_arg(signed char);
2199				break;
2200			case FORMAT_TYPE_USHORT:
2201				num = get_arg(unsigned short);
2202				break;
2203			case FORMAT_TYPE_SHORT:
2204				num = get_arg(short);
2205				break;
2206			case FORMAT_TYPE_UINT:
2207				num = get_arg(unsigned int);
2208				break;
2209			default:
2210				num = get_arg(int);
2211			}
2212
2213			str = number(str, end, num, spec);
2214		} /* default: */
2215		} /* switch(spec.type) */
2216	} /* while(*fmt) */
2217
 
2218	if (size > 0) {
2219		if (str < end)
2220			*str = '\0';
2221		else
2222			end[-1] = '\0';
2223	}
2224
2225#undef get_arg
2226
2227	/* the trailing null byte doesn't count towards the total */
2228	return str - buf;
2229}
2230EXPORT_SYMBOL_GPL(bstr_printf);
2231
2232/**
2233 * bprintf - Parse a format string and place args' binary value in a buffer
2234 * @bin_buf: The buffer to place args' binary value
2235 * @size: The size of the buffer(by words(32bits), not characters)
2236 * @fmt: The format string to use
2237 * @...: Arguments for the format string
2238 *
2239 * The function returns the number of words(u32) written
2240 * into @bin_buf.
2241 */
2242int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2243{
2244	va_list args;
2245	int ret;
2246
2247	va_start(args, fmt);
2248	ret = vbin_printf(bin_buf, size, fmt, args);
2249	va_end(args);
2250
2251	return ret;
2252}
2253EXPORT_SYMBOL_GPL(bprintf);
2254
2255#endif /* CONFIG_BINARY_PRINTF */
2256
2257/**
2258 * vsscanf - Unformat a buffer into a list of arguments
2259 * @buf:	input buffer
2260 * @fmt:	format of buffer
2261 * @args:	arguments
2262 */
2263int vsscanf(const char *buf, const char *fmt, va_list args)
2264{
2265	const char *str = buf;
2266	char *next;
2267	char digit;
2268	int num = 0;
2269	u8 qualifier;
2270	unsigned int base;
2271	union {
2272		long long s;
2273		unsigned long long u;
2274	} val;
2275	s16 field_width;
2276	bool is_sign;
2277
2278	while (*fmt) {
2279		/* skip any white space in format */
2280		/* white space in format matchs any amount of
2281		 * white space, including none, in the input.
2282		 */
2283		if (isspace(*fmt)) {
2284			fmt = skip_spaces(++fmt);
2285			str = skip_spaces(str);
2286		}
2287
2288		/* anything that is not a conversion must match exactly */
2289		if (*fmt != '%' && *fmt) {
2290			if (*fmt++ != *str++)
2291				break;
2292			continue;
2293		}
2294
2295		if (!*fmt)
2296			break;
2297		++fmt;
2298
2299		/* skip this conversion.
2300		 * advance both strings to next white space
2301		 */
2302		if (*fmt == '*') {
2303			if (!*str)
2304				break;
2305			while (!isspace(*fmt) && *fmt != '%' && *fmt)
 
 
 
2306				fmt++;
 
2307			while (!isspace(*str) && *str)
2308				str++;
2309			continue;
2310		}
2311
2312		/* get field width */
2313		field_width = -1;
2314		if (isdigit(*fmt)) {
2315			field_width = skip_atoi(&fmt);
2316			if (field_width <= 0)
2317				break;
2318		}
2319
2320		/* get conversion qualifier */
2321		qualifier = -1;
2322		if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2323		    _tolower(*fmt) == 'z') {
2324			qualifier = *fmt++;
2325			if (unlikely(qualifier == *fmt)) {
2326				if (qualifier == 'h') {
2327					qualifier = 'H';
2328					fmt++;
2329				} else if (qualifier == 'l') {
2330					qualifier = 'L';
2331					fmt++;
2332				}
2333			}
2334		}
2335
2336		if (!*fmt)
2337			break;
2338
2339		if (*fmt == 'n') {
2340			/* return number of characters read so far */
2341			*va_arg(args, int *) = str - buf;
2342			++fmt;
2343			continue;
2344		}
2345
2346		if (!*str)
2347			break;
2348
2349		base = 10;
2350		is_sign = 0;
2351
2352		switch (*fmt++) {
2353		case 'c':
2354		{
2355			char *s = (char *)va_arg(args, char*);
2356			if (field_width == -1)
2357				field_width = 1;
2358			do {
2359				*s++ = *str++;
2360			} while (--field_width > 0 && *str);
2361			num++;
2362		}
2363		continue;
2364		case 's':
2365		{
2366			char *s = (char *)va_arg(args, char *);
2367			if (field_width == -1)
2368				field_width = SHRT_MAX;
2369			/* first, skip leading white space in buffer */
2370			str = skip_spaces(str);
2371
2372			/* now copy until next white space */
2373			while (*str && !isspace(*str) && field_width--)
2374				*s++ = *str++;
2375			*s = '\0';
2376			num++;
2377		}
2378		continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2379		case 'o':
2380			base = 8;
2381			break;
2382		case 'x':
2383		case 'X':
2384			base = 16;
2385			break;
2386		case 'i':
2387			base = 0;
2388		case 'd':
2389			is_sign = 1;
2390		case 'u':
2391			break;
2392		case '%':
2393			/* looking for '%' in str */
2394			if (*str++ != '%')
2395				return num;
2396			continue;
2397		default:
2398			/* invalid format; stop here */
2399			return num;
2400		}
2401
2402		/* have some sort of integer conversion.
2403		 * first, skip white space in buffer.
2404		 */
2405		str = skip_spaces(str);
2406
2407		digit = *str;
2408		if (is_sign && digit == '-')
2409			digit = *(str + 1);
2410
2411		if (!digit
2412		    || (base == 16 && !isxdigit(digit))
2413		    || (base == 10 && !isdigit(digit))
2414		    || (base == 8 && (!isdigit(digit) || digit > '7'))
2415		    || (base == 0 && !isdigit(digit)))
2416			break;
2417
2418		if (is_sign)
2419			val.s = qualifier != 'L' ?
2420				simple_strtol(str, &next, base) :
2421				simple_strtoll(str, &next, base);
2422		else
2423			val.u = qualifier != 'L' ?
2424				simple_strtoul(str, &next, base) :
2425				simple_strtoull(str, &next, base);
2426
2427		if (field_width > 0 && next - str > field_width) {
2428			if (base == 0)
2429				_parse_integer_fixup_radix(str, &base);
2430			while (next - str > field_width) {
2431				if (is_sign)
2432					val.s = div_s64(val.s, base);
2433				else
2434					val.u = div_u64(val.u, base);
2435				--next;
2436			}
2437		}
2438
2439		switch (qualifier) {
2440		case 'H':	/* that's 'hh' in format */
2441			if (is_sign)
2442				*va_arg(args, signed char *) = val.s;
2443			else
2444				*va_arg(args, unsigned char *) = val.u;
2445			break;
2446		case 'h':
2447			if (is_sign)
2448				*va_arg(args, short *) = val.s;
2449			else
2450				*va_arg(args, unsigned short *) = val.u;
2451			break;
2452		case 'l':
2453			if (is_sign)
2454				*va_arg(args, long *) = val.s;
2455			else
2456				*va_arg(args, unsigned long *) = val.u;
2457			break;
2458		case 'L':
2459			if (is_sign)
2460				*va_arg(args, long long *) = val.s;
2461			else
2462				*va_arg(args, unsigned long long *) = val.u;
2463			break;
2464		case 'Z':
2465		case 'z':
2466			*va_arg(args, size_t *) = val.u;
2467			break;
2468		default:
2469			if (is_sign)
2470				*va_arg(args, int *) = val.s;
2471			else
2472				*va_arg(args, unsigned int *) = val.u;
2473			break;
2474		}
2475		num++;
2476
2477		if (!next)
2478			break;
2479		str = next;
2480	}
2481
2482	return num;
2483}
2484EXPORT_SYMBOL(vsscanf);
2485
2486/**
2487 * sscanf - Unformat a buffer into a list of arguments
2488 * @buf:	input buffer
2489 * @fmt:	formatting of buffer
2490 * @...:	resulting arguments
2491 */
2492int sscanf(const char *buf, const char *fmt, ...)
2493{
2494	va_list args;
2495	int i;
2496
2497	va_start(args, fmt);
2498	i = vsscanf(buf, fmt, args);
2499	va_end(args);
2500
2501	return i;
2502}
2503EXPORT_SYMBOL(sscanf);