xref: /linux/lib/vsprintf.c (revision 148f9bb87745ed45f7a11b2cbd3bc0f017d5d257)
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 <net/addrconf.h>
30 
31 #include <asm/page.h>		/* for PAGE_SIZE */
32 #include <asm/sections.h>	/* for dereference_function_descriptor() */
33 
34 #include "kstrtox.h"
35 
36 /**
37  * simple_strtoull - convert a string to an unsigned long long
38  * @cp: The start of the string
39  * @endp: A pointer to the end of the parsed string will be placed here
40  * @base: The number base to use
41  *
42  * This function is obsolete. Please use kstrtoull instead.
43  */
44 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
45 {
46 	unsigned long long result;
47 	unsigned int rv;
48 
49 	cp = _parse_integer_fixup_radix(cp, &base);
50 	rv = _parse_integer(cp, base, &result);
51 	/* FIXME */
52 	cp += (rv & ~KSTRTOX_OVERFLOW);
53 
54 	if (endp)
55 		*endp = (char *)cp;
56 
57 	return result;
58 }
59 EXPORT_SYMBOL(simple_strtoull);
60 
61 /**
62  * simple_strtoul - convert a string to an unsigned long
63  * @cp: The start of the string
64  * @endp: A pointer to the end of the parsed string will be placed here
65  * @base: The number base to use
66  *
67  * This function is obsolete. Please use kstrtoul instead.
68  */
69 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
70 {
71 	return simple_strtoull(cp, endp, base);
72 }
73 EXPORT_SYMBOL(simple_strtoul);
74 
75 /**
76  * simple_strtol - convert a string to a signed long
77  * @cp: The start of the string
78  * @endp: A pointer to the end of the parsed string will be placed here
79  * @base: The number base to use
80  *
81  * This function is obsolete. Please use kstrtol instead.
82  */
83 long simple_strtol(const char *cp, char **endp, unsigned int base)
84 {
85 	if (*cp == '-')
86 		return -simple_strtoul(cp + 1, endp, base);
87 
88 	return simple_strtoul(cp, endp, base);
89 }
90 EXPORT_SYMBOL(simple_strtol);
91 
92 /**
93  * simple_strtoll - convert a string to a signed long long
94  * @cp: The start of the string
95  * @endp: A pointer to the end of the parsed string will be placed here
96  * @base: The number base to use
97  *
98  * This function is obsolete. Please use kstrtoll instead.
99  */
100 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
101 {
102 	if (*cp == '-')
103 		return -simple_strtoull(cp + 1, endp, base);
104 
105 	return simple_strtoull(cp, endp, base);
106 }
107 EXPORT_SYMBOL(simple_strtoll);
108 
109 static noinline_for_stack
110 int skip_atoi(const char **s)
111 {
112 	int i = 0;
113 
114 	while (isdigit(**s))
115 		i = i*10 + *((*s)++) - '0';
116 
117 	return i;
118 }
119 
120 /* Decimal conversion is by far the most typical, and is used
121  * for /proc and /sys data. This directly impacts e.g. top performance
122  * with many processes running. We optimize it for speed
123  * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
124  * (with permission from the author, Douglas W. Jones).
125  */
126 
127 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
128 /* Formats correctly any integer in [0, 999999999] */
129 static noinline_for_stack
130 char *put_dec_full9(char *buf, unsigned q)
131 {
132 	unsigned r;
133 
134 	/*
135 	 * Possible ways to approx. divide by 10
136 	 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
137 	 * (x * 0xcccd) >> 19     x <      81920 (x < 262149 when 64-bit mul)
138 	 * (x * 0x6667) >> 18     x <      43699
139 	 * (x * 0x3334) >> 17     x <      16389
140 	 * (x * 0x199a) >> 16     x <      16389
141 	 * (x * 0x0ccd) >> 15     x <      16389
142 	 * (x * 0x0667) >> 14     x <       2739
143 	 * (x * 0x0334) >> 13     x <       1029
144 	 * (x * 0x019a) >> 12     x <       1029
145 	 * (x * 0x00cd) >> 11     x <       1029 shorter code than * 0x67 (on i386)
146 	 * (x * 0x0067) >> 10     x <        179
147 	 * (x * 0x0034) >>  9     x <         69 same
148 	 * (x * 0x001a) >>  8     x <         69 same
149 	 * (x * 0x000d) >>  7     x <         69 same, shortest code (on i386)
150 	 * (x * 0x0007) >>  6     x <         19
151 	 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
152 	 */
153 	r      = (q * (uint64_t)0x1999999a) >> 32;
154 	*buf++ = (q - 10 * r) + '0'; /* 1 */
155 	q      = (r * (uint64_t)0x1999999a) >> 32;
156 	*buf++ = (r - 10 * q) + '0'; /* 2 */
157 	r      = (q * (uint64_t)0x1999999a) >> 32;
158 	*buf++ = (q - 10 * r) + '0'; /* 3 */
159 	q      = (r * (uint64_t)0x1999999a) >> 32;
160 	*buf++ = (r - 10 * q) + '0'; /* 4 */
161 	r      = (q * (uint64_t)0x1999999a) >> 32;
162 	*buf++ = (q - 10 * r) + '0'; /* 5 */
163 	/* Now value is under 10000, can avoid 64-bit multiply */
164 	q      = (r * 0x199a) >> 16;
165 	*buf++ = (r - 10 * q)  + '0'; /* 6 */
166 	r      = (q * 0xcd) >> 11;
167 	*buf++ = (q - 10 * r)  + '0'; /* 7 */
168 	q      = (r * 0xcd) >> 11;
169 	*buf++ = (r - 10 * q) + '0'; /* 8 */
170 	*buf++ = q + '0'; /* 9 */
171 	return buf;
172 }
173 #endif
174 
175 /* Similar to above but do not pad with zeros.
176  * Code can be easily arranged to print 9 digits too, but our callers
177  * always call put_dec_full9() instead when the number has 9 decimal digits.
178  */
179 static noinline_for_stack
180 char *put_dec_trunc8(char *buf, unsigned r)
181 {
182 	unsigned q;
183 
184 	/* Copy of previous function's body with added early returns */
185 	while (r >= 10000) {
186 		q = r + '0';
187 		r  = (r * (uint64_t)0x1999999a) >> 32;
188 		*buf++ = q - 10*r;
189 	}
190 
191 	q      = (r * 0x199a) >> 16;	/* r <= 9999 */
192 	*buf++ = (r - 10 * q)  + '0';
193 	if (q == 0)
194 		return buf;
195 	r      = (q * 0xcd) >> 11;	/* q <= 999 */
196 	*buf++ = (q - 10 * r)  + '0';
197 	if (r == 0)
198 		return buf;
199 	q      = (r * 0xcd) >> 11;	/* r <= 99 */
200 	*buf++ = (r - 10 * q) + '0';
201 	if (q == 0)
202 		return buf;
203 	*buf++ = q + '0';		 /* q <= 9 */
204 	return buf;
205 }
206 
207 /* There are two algorithms to print larger numbers.
208  * One is generic: divide by 1000000000 and repeatedly print
209  * groups of (up to) 9 digits. It's conceptually simple,
210  * but requires a (unsigned long long) / 1000000000 division.
211  *
212  * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
213  * manipulates them cleverly and generates groups of 4 decimal digits.
214  * It so happens that it does NOT require long long division.
215  *
216  * If long is > 32 bits, division of 64-bit values is relatively easy,
217  * and we will use the first algorithm.
218  * If long long is > 64 bits (strange architecture with VERY large long long),
219  * second algorithm can't be used, and we again use the first one.
220  *
221  * Else (if long is 32 bits and long long is 64 bits) we use second one.
222  */
223 
224 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
225 
226 /* First algorithm: generic */
227 
228 static
229 char *put_dec(char *buf, unsigned long long n)
230 {
231 	if (n >= 100*1000*1000) {
232 		while (n >= 1000*1000*1000)
233 			buf = put_dec_full9(buf, do_div(n, 1000*1000*1000));
234 		if (n >= 100*1000*1000)
235 			return put_dec_full9(buf, n);
236 	}
237 	return put_dec_trunc8(buf, n);
238 }
239 
240 #else
241 
242 /* Second algorithm: valid only for 64-bit long longs */
243 
244 /* See comment in put_dec_full9 for choice of constants */
245 static noinline_for_stack
246 void put_dec_full4(char *buf, unsigned q)
247 {
248 	unsigned r;
249 	r      = (q * 0xccd) >> 15;
250 	buf[0] = (q - 10 * r) + '0';
251 	q      = (r * 0xcd) >> 11;
252 	buf[1] = (r - 10 * q)  + '0';
253 	r      = (q * 0xcd) >> 11;
254 	buf[2] = (q - 10 * r)  + '0';
255 	buf[3] = r + '0';
256 }
257 
258 /*
259  * Call put_dec_full4 on x % 10000, return x / 10000.
260  * The approximation x/10000 == (x * 0x346DC5D7) >> 43
261  * holds for all x < 1,128,869,999.  The largest value this
262  * helper will ever be asked to convert is 1,125,520,955.
263  * (d1 in the put_dec code, assuming n is all-ones).
264  */
265 static
266 unsigned put_dec_helper4(char *buf, unsigned x)
267 {
268         uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
269 
270         put_dec_full4(buf, x - q * 10000);
271         return q;
272 }
273 
274 /* Based on code by Douglas W. Jones found at
275  * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
276  * (with permission from the author).
277  * Performs no 64-bit division and hence should be fast on 32-bit machines.
278  */
279 static
280 char *put_dec(char *buf, unsigned long long n)
281 {
282 	uint32_t d3, d2, d1, q, h;
283 
284 	if (n < 100*1000*1000)
285 		return put_dec_trunc8(buf, n);
286 
287 	d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
288 	h   = (n >> 32);
289 	d2  = (h      ) & 0xffff;
290 	d3  = (h >> 16); /* implicit "& 0xffff" */
291 
292 	q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
293 	q = put_dec_helper4(buf, q);
294 
295 	q += 7671 * d3 + 9496 * d2 + 6 * d1;
296 	q = put_dec_helper4(buf+4, q);
297 
298 	q += 4749 * d3 + 42 * d2;
299 	q = put_dec_helper4(buf+8, q);
300 
301 	q += 281 * d3;
302 	buf += 12;
303 	if (q)
304 		buf = put_dec_trunc8(buf, q);
305 	else while (buf[-1] == '0')
306 		--buf;
307 
308 	return buf;
309 }
310 
311 #endif
312 
313 /*
314  * Convert passed number to decimal string.
315  * Returns the length of string.  On buffer overflow, returns 0.
316  *
317  * If speed is not important, use snprintf(). It's easy to read the code.
318  */
319 int num_to_str(char *buf, int size, unsigned long long num)
320 {
321 	char tmp[sizeof(num) * 3];
322 	int idx, len;
323 
324 	/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
325 	if (num <= 9) {
326 		tmp[0] = '0' + num;
327 		len = 1;
328 	} else {
329 		len = put_dec(tmp, num) - tmp;
330 	}
331 
332 	if (len > size)
333 		return 0;
334 	for (idx = 0; idx < len; ++idx)
335 		buf[idx] = tmp[len - idx - 1];
336 	return len;
337 }
338 
339 #define ZEROPAD	1		/* pad with zero */
340 #define SIGN	2		/* unsigned/signed long */
341 #define PLUS	4		/* show plus */
342 #define SPACE	8		/* space if plus */
343 #define LEFT	16		/* left justified */
344 #define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
345 #define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
346 
347 enum format_type {
348 	FORMAT_TYPE_NONE, /* Just a string part */
349 	FORMAT_TYPE_WIDTH,
350 	FORMAT_TYPE_PRECISION,
351 	FORMAT_TYPE_CHAR,
352 	FORMAT_TYPE_STR,
353 	FORMAT_TYPE_PTR,
354 	FORMAT_TYPE_PERCENT_CHAR,
355 	FORMAT_TYPE_INVALID,
356 	FORMAT_TYPE_LONG_LONG,
357 	FORMAT_TYPE_ULONG,
358 	FORMAT_TYPE_LONG,
359 	FORMAT_TYPE_UBYTE,
360 	FORMAT_TYPE_BYTE,
361 	FORMAT_TYPE_USHORT,
362 	FORMAT_TYPE_SHORT,
363 	FORMAT_TYPE_UINT,
364 	FORMAT_TYPE_INT,
365 	FORMAT_TYPE_NRCHARS,
366 	FORMAT_TYPE_SIZE_T,
367 	FORMAT_TYPE_PTRDIFF
368 };
369 
370 struct printf_spec {
371 	u8	type;		/* format_type enum */
372 	u8	flags;		/* flags to number() */
373 	u8	base;		/* number base, 8, 10 or 16 only */
374 	u8	qualifier;	/* number qualifier, one of 'hHlLtzZ' */
375 	s16	field_width;	/* width of output field */
376 	s16	precision;	/* # of digits/chars */
377 };
378 
379 static noinline_for_stack
380 char *number(char *buf, char *end, unsigned long long num,
381 	     struct printf_spec spec)
382 {
383 	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
384 	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
385 
386 	char tmp[66];
387 	char sign;
388 	char locase;
389 	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
390 	int i;
391 	bool is_zero = num == 0LL;
392 
393 	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
394 	 * produces same digits or (maybe lowercased) letters */
395 	locase = (spec.flags & SMALL);
396 	if (spec.flags & LEFT)
397 		spec.flags &= ~ZEROPAD;
398 	sign = 0;
399 	if (spec.flags & SIGN) {
400 		if ((signed long long)num < 0) {
401 			sign = '-';
402 			num = -(signed long long)num;
403 			spec.field_width--;
404 		} else if (spec.flags & PLUS) {
405 			sign = '+';
406 			spec.field_width--;
407 		} else if (spec.flags & SPACE) {
408 			sign = ' ';
409 			spec.field_width--;
410 		}
411 	}
412 	if (need_pfx) {
413 		if (spec.base == 16)
414 			spec.field_width -= 2;
415 		else if (!is_zero)
416 			spec.field_width--;
417 	}
418 
419 	/* generate full string in tmp[], in reverse order */
420 	i = 0;
421 	if (num < spec.base)
422 		tmp[i++] = digits[num] | locase;
423 	/* Generic code, for any base:
424 	else do {
425 		tmp[i++] = (digits[do_div(num,base)] | locase);
426 	} while (num != 0);
427 	*/
428 	else if (spec.base != 10) { /* 8 or 16 */
429 		int mask = spec.base - 1;
430 		int shift = 3;
431 
432 		if (spec.base == 16)
433 			shift = 4;
434 		do {
435 			tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
436 			num >>= shift;
437 		} while (num);
438 	} else { /* base 10 */
439 		i = put_dec(tmp, num) - tmp;
440 	}
441 
442 	/* printing 100 using %2d gives "100", not "00" */
443 	if (i > spec.precision)
444 		spec.precision = i;
445 	/* leading space padding */
446 	spec.field_width -= spec.precision;
447 	if (!(spec.flags & (ZEROPAD+LEFT))) {
448 		while (--spec.field_width >= 0) {
449 			if (buf < end)
450 				*buf = ' ';
451 			++buf;
452 		}
453 	}
454 	/* sign */
455 	if (sign) {
456 		if (buf < end)
457 			*buf = sign;
458 		++buf;
459 	}
460 	/* "0x" / "0" prefix */
461 	if (need_pfx) {
462 		if (spec.base == 16 || !is_zero) {
463 			if (buf < end)
464 				*buf = '0';
465 			++buf;
466 		}
467 		if (spec.base == 16) {
468 			if (buf < end)
469 				*buf = ('X' | locase);
470 			++buf;
471 		}
472 	}
473 	/* zero or space padding */
474 	if (!(spec.flags & LEFT)) {
475 		char c = (spec.flags & ZEROPAD) ? '0' : ' ';
476 		while (--spec.field_width >= 0) {
477 			if (buf < end)
478 				*buf = c;
479 			++buf;
480 		}
481 	}
482 	/* hmm even more zero padding? */
483 	while (i <= --spec.precision) {
484 		if (buf < end)
485 			*buf = '0';
486 		++buf;
487 	}
488 	/* actual digits of result */
489 	while (--i >= 0) {
490 		if (buf < end)
491 			*buf = tmp[i];
492 		++buf;
493 	}
494 	/* trailing space padding */
495 	while (--spec.field_width >= 0) {
496 		if (buf < end)
497 			*buf = ' ';
498 		++buf;
499 	}
500 
501 	return buf;
502 }
503 
504 static noinline_for_stack
505 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
506 {
507 	int len, i;
508 
509 	if ((unsigned long)s < PAGE_SIZE)
510 		s = "(null)";
511 
512 	len = strnlen(s, spec.precision);
513 
514 	if (!(spec.flags & LEFT)) {
515 		while (len < spec.field_width--) {
516 			if (buf < end)
517 				*buf = ' ';
518 			++buf;
519 		}
520 	}
521 	for (i = 0; i < len; ++i) {
522 		if (buf < end)
523 			*buf = *s;
524 		++buf; ++s;
525 	}
526 	while (len < spec.field_width--) {
527 		if (buf < end)
528 			*buf = ' ';
529 		++buf;
530 	}
531 
532 	return buf;
533 }
534 
535 static noinline_for_stack
536 char *symbol_string(char *buf, char *end, void *ptr,
537 		    struct printf_spec spec, const char *fmt)
538 {
539 	unsigned long value;
540 #ifdef CONFIG_KALLSYMS
541 	char sym[KSYM_SYMBOL_LEN];
542 #endif
543 
544 	if (fmt[1] == 'R')
545 		ptr = __builtin_extract_return_addr(ptr);
546 	value = (unsigned long)ptr;
547 
548 #ifdef CONFIG_KALLSYMS
549 	if (*fmt == 'B')
550 		sprint_backtrace(sym, value);
551 	else if (*fmt != 'f' && *fmt != 's')
552 		sprint_symbol(sym, value);
553 	else
554 		sprint_symbol_no_offset(sym, value);
555 
556 	return string(buf, end, sym, spec);
557 #else
558 	spec.field_width = 2 * sizeof(void *);
559 	spec.flags |= SPECIAL | SMALL | ZEROPAD;
560 	spec.base = 16;
561 
562 	return number(buf, end, value, spec);
563 #endif
564 }
565 
566 static noinline_for_stack
567 char *resource_string(char *buf, char *end, struct resource *res,
568 		      struct printf_spec spec, const char *fmt)
569 {
570 #ifndef IO_RSRC_PRINTK_SIZE
571 #define IO_RSRC_PRINTK_SIZE	6
572 #endif
573 
574 #ifndef MEM_RSRC_PRINTK_SIZE
575 #define MEM_RSRC_PRINTK_SIZE	10
576 #endif
577 	static const struct printf_spec io_spec = {
578 		.base = 16,
579 		.field_width = IO_RSRC_PRINTK_SIZE,
580 		.precision = -1,
581 		.flags = SPECIAL | SMALL | ZEROPAD,
582 	};
583 	static const struct printf_spec mem_spec = {
584 		.base = 16,
585 		.field_width = MEM_RSRC_PRINTK_SIZE,
586 		.precision = -1,
587 		.flags = SPECIAL | SMALL | ZEROPAD,
588 	};
589 	static const struct printf_spec bus_spec = {
590 		.base = 16,
591 		.field_width = 2,
592 		.precision = -1,
593 		.flags = SMALL | ZEROPAD,
594 	};
595 	static const struct printf_spec dec_spec = {
596 		.base = 10,
597 		.precision = -1,
598 		.flags = 0,
599 	};
600 	static const struct printf_spec str_spec = {
601 		.field_width = -1,
602 		.precision = 10,
603 		.flags = LEFT,
604 	};
605 	static const struct printf_spec flag_spec = {
606 		.base = 16,
607 		.precision = -1,
608 		.flags = SPECIAL | SMALL,
609 	};
610 
611 	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
612 	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
613 #define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
614 #define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
615 #define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
616 #define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
617 	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
618 		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
619 
620 	char *p = sym, *pend = sym + sizeof(sym);
621 	int decode = (fmt[0] == 'R') ? 1 : 0;
622 	const struct printf_spec *specp;
623 
624 	*p++ = '[';
625 	if (res->flags & IORESOURCE_IO) {
626 		p = string(p, pend, "io  ", str_spec);
627 		specp = &io_spec;
628 	} else if (res->flags & IORESOURCE_MEM) {
629 		p = string(p, pend, "mem ", str_spec);
630 		specp = &mem_spec;
631 	} else if (res->flags & IORESOURCE_IRQ) {
632 		p = string(p, pend, "irq ", str_spec);
633 		specp = &dec_spec;
634 	} else if (res->flags & IORESOURCE_DMA) {
635 		p = string(p, pend, "dma ", str_spec);
636 		specp = &dec_spec;
637 	} else if (res->flags & IORESOURCE_BUS) {
638 		p = string(p, pend, "bus ", str_spec);
639 		specp = &bus_spec;
640 	} else {
641 		p = string(p, pend, "??? ", str_spec);
642 		specp = &mem_spec;
643 		decode = 0;
644 	}
645 	p = number(p, pend, res->start, *specp);
646 	if (res->start != res->end) {
647 		*p++ = '-';
648 		p = number(p, pend, res->end, *specp);
649 	}
650 	if (decode) {
651 		if (res->flags & IORESOURCE_MEM_64)
652 			p = string(p, pend, " 64bit", str_spec);
653 		if (res->flags & IORESOURCE_PREFETCH)
654 			p = string(p, pend, " pref", str_spec);
655 		if (res->flags & IORESOURCE_WINDOW)
656 			p = string(p, pend, " window", str_spec);
657 		if (res->flags & IORESOURCE_DISABLED)
658 			p = string(p, pend, " disabled", str_spec);
659 	} else {
660 		p = string(p, pend, " flags ", str_spec);
661 		p = number(p, pend, res->flags, flag_spec);
662 	}
663 	*p++ = ']';
664 	*p = '\0';
665 
666 	return string(buf, end, sym, spec);
667 }
668 
669 static noinline_for_stack
670 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
671 		 const char *fmt)
672 {
673 	int i, len = 1;		/* if we pass '%ph[CDN]', field width remains
674 				   negative value, fallback to the default */
675 	char separator;
676 
677 	if (spec.field_width == 0)
678 		/* nothing to print */
679 		return buf;
680 
681 	if (ZERO_OR_NULL_PTR(addr))
682 		/* NULL pointer */
683 		return string(buf, end, NULL, spec);
684 
685 	switch (fmt[1]) {
686 	case 'C':
687 		separator = ':';
688 		break;
689 	case 'D':
690 		separator = '-';
691 		break;
692 	case 'N':
693 		separator = 0;
694 		break;
695 	default:
696 		separator = ' ';
697 		break;
698 	}
699 
700 	if (spec.field_width > 0)
701 		len = min_t(int, spec.field_width, 64);
702 
703 	for (i = 0; i < len && buf < end - 1; i++) {
704 		buf = hex_byte_pack(buf, addr[i]);
705 
706 		if (buf < end && separator && i != len - 1)
707 			*buf++ = separator;
708 	}
709 
710 	return buf;
711 }
712 
713 static noinline_for_stack
714 char *mac_address_string(char *buf, char *end, u8 *addr,
715 			 struct printf_spec spec, const char *fmt)
716 {
717 	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
718 	char *p = mac_addr;
719 	int i;
720 	char separator;
721 	bool reversed = false;
722 
723 	switch (fmt[1]) {
724 	case 'F':
725 		separator = '-';
726 		break;
727 
728 	case 'R':
729 		reversed = true;
730 		/* fall through */
731 
732 	default:
733 		separator = ':';
734 		break;
735 	}
736 
737 	for (i = 0; i < 6; i++) {
738 		if (reversed)
739 			p = hex_byte_pack(p, addr[5 - i]);
740 		else
741 			p = hex_byte_pack(p, addr[i]);
742 
743 		if (fmt[0] == 'M' && i != 5)
744 			*p++ = separator;
745 	}
746 	*p = '\0';
747 
748 	return string(buf, end, mac_addr, spec);
749 }
750 
751 static noinline_for_stack
752 char *ip4_string(char *p, const u8 *addr, const char *fmt)
753 {
754 	int i;
755 	bool leading_zeros = (fmt[0] == 'i');
756 	int index;
757 	int step;
758 
759 	switch (fmt[2]) {
760 	case 'h':
761 #ifdef __BIG_ENDIAN
762 		index = 0;
763 		step = 1;
764 #else
765 		index = 3;
766 		step = -1;
767 #endif
768 		break;
769 	case 'l':
770 		index = 3;
771 		step = -1;
772 		break;
773 	case 'n':
774 	case 'b':
775 	default:
776 		index = 0;
777 		step = 1;
778 		break;
779 	}
780 	for (i = 0; i < 4; i++) {
781 		char temp[3];	/* hold each IP quad in reverse order */
782 		int digits = put_dec_trunc8(temp, addr[index]) - temp;
783 		if (leading_zeros) {
784 			if (digits < 3)
785 				*p++ = '0';
786 			if (digits < 2)
787 				*p++ = '0';
788 		}
789 		/* reverse the digits in the quad */
790 		while (digits--)
791 			*p++ = temp[digits];
792 		if (i < 3)
793 			*p++ = '.';
794 		index += step;
795 	}
796 	*p = '\0';
797 
798 	return p;
799 }
800 
801 static noinline_for_stack
802 char *ip6_compressed_string(char *p, const char *addr)
803 {
804 	int i, j, range;
805 	unsigned char zerolength[8];
806 	int longest = 1;
807 	int colonpos = -1;
808 	u16 word;
809 	u8 hi, lo;
810 	bool needcolon = false;
811 	bool useIPv4;
812 	struct in6_addr in6;
813 
814 	memcpy(&in6, addr, sizeof(struct in6_addr));
815 
816 	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
817 
818 	memset(zerolength, 0, sizeof(zerolength));
819 
820 	if (useIPv4)
821 		range = 6;
822 	else
823 		range = 8;
824 
825 	/* find position of longest 0 run */
826 	for (i = 0; i < range; i++) {
827 		for (j = i; j < range; j++) {
828 			if (in6.s6_addr16[j] != 0)
829 				break;
830 			zerolength[i]++;
831 		}
832 	}
833 	for (i = 0; i < range; i++) {
834 		if (zerolength[i] > longest) {
835 			longest = zerolength[i];
836 			colonpos = i;
837 		}
838 	}
839 	if (longest == 1)		/* don't compress a single 0 */
840 		colonpos = -1;
841 
842 	/* emit address */
843 	for (i = 0; i < range; i++) {
844 		if (i == colonpos) {
845 			if (needcolon || i == 0)
846 				*p++ = ':';
847 			*p++ = ':';
848 			needcolon = false;
849 			i += longest - 1;
850 			continue;
851 		}
852 		if (needcolon) {
853 			*p++ = ':';
854 			needcolon = false;
855 		}
856 		/* hex u16 without leading 0s */
857 		word = ntohs(in6.s6_addr16[i]);
858 		hi = word >> 8;
859 		lo = word & 0xff;
860 		if (hi) {
861 			if (hi > 0x0f)
862 				p = hex_byte_pack(p, hi);
863 			else
864 				*p++ = hex_asc_lo(hi);
865 			p = hex_byte_pack(p, lo);
866 		}
867 		else if (lo > 0x0f)
868 			p = hex_byte_pack(p, lo);
869 		else
870 			*p++ = hex_asc_lo(lo);
871 		needcolon = true;
872 	}
873 
874 	if (useIPv4) {
875 		if (needcolon)
876 			*p++ = ':';
877 		p = ip4_string(p, &in6.s6_addr[12], "I4");
878 	}
879 	*p = '\0';
880 
881 	return p;
882 }
883 
884 static noinline_for_stack
885 char *ip6_string(char *p, const char *addr, const char *fmt)
886 {
887 	int i;
888 
889 	for (i = 0; i < 8; i++) {
890 		p = hex_byte_pack(p, *addr++);
891 		p = hex_byte_pack(p, *addr++);
892 		if (fmt[0] == 'I' && i != 7)
893 			*p++ = ':';
894 	}
895 	*p = '\0';
896 
897 	return p;
898 }
899 
900 static noinline_for_stack
901 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
902 		      struct printf_spec spec, const char *fmt)
903 {
904 	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
905 
906 	if (fmt[0] == 'I' && fmt[2] == 'c')
907 		ip6_compressed_string(ip6_addr, addr);
908 	else
909 		ip6_string(ip6_addr, addr, fmt);
910 
911 	return string(buf, end, ip6_addr, spec);
912 }
913 
914 static noinline_for_stack
915 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
916 		      struct printf_spec spec, const char *fmt)
917 {
918 	char ip4_addr[sizeof("255.255.255.255")];
919 
920 	ip4_string(ip4_addr, addr, fmt);
921 
922 	return string(buf, end, ip4_addr, spec);
923 }
924 
925 static noinline_for_stack
926 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
927 			 struct printf_spec spec, const char *fmt)
928 {
929 	bool have_p = false, have_s = false, have_f = false, have_c = false;
930 	char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
931 		      sizeof(":12345") + sizeof("/123456789") +
932 		      sizeof("%1234567890")];
933 	char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
934 	const u8 *addr = (const u8 *) &sa->sin6_addr;
935 	char fmt6[2] = { fmt[0], '6' };
936 	u8 off = 0;
937 
938 	fmt++;
939 	while (isalpha(*++fmt)) {
940 		switch (*fmt) {
941 		case 'p':
942 			have_p = true;
943 			break;
944 		case 'f':
945 			have_f = true;
946 			break;
947 		case 's':
948 			have_s = true;
949 			break;
950 		case 'c':
951 			have_c = true;
952 			break;
953 		}
954 	}
955 
956 	if (have_p || have_s || have_f) {
957 		*p = '[';
958 		off = 1;
959 	}
960 
961 	if (fmt6[0] == 'I' && have_c)
962 		p = ip6_compressed_string(ip6_addr + off, addr);
963 	else
964 		p = ip6_string(ip6_addr + off, addr, fmt6);
965 
966 	if (have_p || have_s || have_f)
967 		*p++ = ']';
968 
969 	if (have_p) {
970 		*p++ = ':';
971 		p = number(p, pend, ntohs(sa->sin6_port), spec);
972 	}
973 	if (have_f) {
974 		*p++ = '/';
975 		p = number(p, pend, ntohl(sa->sin6_flowinfo &
976 					  IPV6_FLOWINFO_MASK), spec);
977 	}
978 	if (have_s) {
979 		*p++ = '%';
980 		p = number(p, pend, sa->sin6_scope_id, spec);
981 	}
982 	*p = '\0';
983 
984 	return string(buf, end, ip6_addr, spec);
985 }
986 
987 static noinline_for_stack
988 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
989 			 struct printf_spec spec, const char *fmt)
990 {
991 	bool have_p = false;
992 	char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
993 	char *pend = ip4_addr + sizeof(ip4_addr);
994 	const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
995 	char fmt4[3] = { fmt[0], '4', 0 };
996 
997 	fmt++;
998 	while (isalpha(*++fmt)) {
999 		switch (*fmt) {
1000 		case 'p':
1001 			have_p = true;
1002 			break;
1003 		case 'h':
1004 		case 'l':
1005 		case 'n':
1006 		case 'b':
1007 			fmt4[2] = *fmt;
1008 			break;
1009 		}
1010 	}
1011 
1012 	p = ip4_string(ip4_addr, addr, fmt4);
1013 	if (have_p) {
1014 		*p++ = ':';
1015 		p = number(p, pend, ntohs(sa->sin_port), spec);
1016 	}
1017 	*p = '\0';
1018 
1019 	return string(buf, end, ip4_addr, spec);
1020 }
1021 
1022 static noinline_for_stack
1023 char *uuid_string(char *buf, char *end, const u8 *addr,
1024 		  struct printf_spec spec, const char *fmt)
1025 {
1026 	char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1027 	char *p = uuid;
1028 	int i;
1029 	static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1030 	static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1031 	const u8 *index = be;
1032 	bool uc = false;
1033 
1034 	switch (*(++fmt)) {
1035 	case 'L':
1036 		uc = true;		/* fall-through */
1037 	case 'l':
1038 		index = le;
1039 		break;
1040 	case 'B':
1041 		uc = true;
1042 		break;
1043 	}
1044 
1045 	for (i = 0; i < 16; i++) {
1046 		p = hex_byte_pack(p, addr[index[i]]);
1047 		switch (i) {
1048 		case 3:
1049 		case 5:
1050 		case 7:
1051 		case 9:
1052 			*p++ = '-';
1053 			break;
1054 		}
1055 	}
1056 
1057 	*p = 0;
1058 
1059 	if (uc) {
1060 		p = uuid;
1061 		do {
1062 			*p = toupper(*p);
1063 		} while (*(++p));
1064 	}
1065 
1066 	return string(buf, end, uuid, spec);
1067 }
1068 
1069 static
1070 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
1071 		      struct printf_spec spec)
1072 {
1073 	spec.flags |= SPECIAL | SMALL | ZEROPAD;
1074 	if (spec.field_width == -1)
1075 		spec.field_width = 2 + 2 * sizeof(netdev_features_t);
1076 	spec.base = 16;
1077 
1078 	return number(buf, end, *(const netdev_features_t *)addr, spec);
1079 }
1080 
1081 int kptr_restrict __read_mostly;
1082 
1083 /*
1084  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1085  * by an extra set of alphanumeric characters that are extended format
1086  * specifiers.
1087  *
1088  * Right now we handle:
1089  *
1090  * - 'F' For symbolic function descriptor pointers with offset
1091  * - 'f' For simple symbolic function names without offset
1092  * - 'S' For symbolic direct pointers with offset
1093  * - 's' For symbolic direct pointers without offset
1094  * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1095  * - 'B' For backtraced symbolic direct pointers with offset
1096  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1097  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1098  * - 'M' For a 6-byte MAC address, it prints the address in the
1099  *       usual colon-separated hex notation
1100  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1101  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1102  *       with a dash-separated hex notation
1103  * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1104  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1105  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1106  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1107  *       [S][pfs]
1108  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1109  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1110  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1111  *       IPv6 omits the colons (01020304...0f)
1112  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1113  *       [S][pfs]
1114  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1115  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1116  * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1117  * - 'I[6S]c' for IPv6 addresses printed as specified by
1118  *       http://tools.ietf.org/html/rfc5952
1119  * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1120  *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1121  *       Options for %pU are:
1122  *         b big endian lower case hex (default)
1123  *         B big endian UPPER case hex
1124  *         l little endian lower case hex
1125  *         L little endian UPPER case hex
1126  *           big endian output byte order is:
1127  *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1128  *           little endian output byte order is:
1129  *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1130  * - 'V' For a struct va_format which contains a format string * and va_list *,
1131  *       call vsnprintf(->format, *->va_list).
1132  *       Implements a "recursive vsnprintf".
1133  *       Do not use this feature without some mechanism to verify the
1134  *       correctness of the format string and va_list arguments.
1135  * - 'K' For a kernel pointer that should be hidden from unprivileged users
1136  * - 'NF' For a netdev_features_t
1137  * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1138  *            a certain separator (' ' by default):
1139  *              C colon
1140  *              D dash
1141  *              N no separator
1142  *            The maximum supported length is 64 bytes of the input. Consider
1143  *            to use print_hex_dump() for the larger input.
1144  * - 'a' For a phys_addr_t type and its derivative types (passed by reference)
1145  *
1146  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1147  * function pointers are really function descriptors, which contain a
1148  * pointer to the real address.
1149  */
1150 static noinline_for_stack
1151 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1152 	      struct printf_spec spec)
1153 {
1154 	int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
1155 
1156 	if (!ptr && *fmt != 'K') {
1157 		/*
1158 		 * Print (null) with the same width as a pointer so it makes
1159 		 * tabular output look nice.
1160 		 */
1161 		if (spec.field_width == -1)
1162 			spec.field_width = default_width;
1163 		return string(buf, end, "(null)", spec);
1164 	}
1165 
1166 	switch (*fmt) {
1167 	case 'F':
1168 	case 'f':
1169 		ptr = dereference_function_descriptor(ptr);
1170 		/* Fallthrough */
1171 	case 'S':
1172 	case 's':
1173 	case 'B':
1174 		return symbol_string(buf, end, ptr, spec, fmt);
1175 	case 'R':
1176 	case 'r':
1177 		return resource_string(buf, end, ptr, spec, fmt);
1178 	case 'h':
1179 		return hex_string(buf, end, ptr, spec, fmt);
1180 	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
1181 	case 'm':			/* Contiguous: 000102030405 */
1182 					/* [mM]F (FDDI) */
1183 					/* [mM]R (Reverse order; Bluetooth) */
1184 		return mac_address_string(buf, end, ptr, spec, fmt);
1185 	case 'I':			/* Formatted IP supported
1186 					 * 4:	1.2.3.4
1187 					 * 6:	0001:0203:...:0708
1188 					 * 6c:	1::708 or 1::1.2.3.4
1189 					 */
1190 	case 'i':			/* Contiguous:
1191 					 * 4:	001.002.003.004
1192 					 * 6:   000102...0f
1193 					 */
1194 		switch (fmt[1]) {
1195 		case '6':
1196 			return ip6_addr_string(buf, end, ptr, spec, fmt);
1197 		case '4':
1198 			return ip4_addr_string(buf, end, ptr, spec, fmt);
1199 		case 'S': {
1200 			const union {
1201 				struct sockaddr		raw;
1202 				struct sockaddr_in	v4;
1203 				struct sockaddr_in6	v6;
1204 			} *sa = ptr;
1205 
1206 			switch (sa->raw.sa_family) {
1207 			case AF_INET:
1208 				return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1209 			case AF_INET6:
1210 				return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1211 			default:
1212 				return string(buf, end, "(invalid address)", spec);
1213 			}}
1214 		}
1215 		break;
1216 	case 'U':
1217 		return uuid_string(buf, end, ptr, spec, fmt);
1218 	case 'V':
1219 		{
1220 			va_list va;
1221 
1222 			va_copy(va, *((struct va_format *)ptr)->va);
1223 			buf += vsnprintf(buf, end > buf ? end - buf : 0,
1224 					 ((struct va_format *)ptr)->fmt, va);
1225 			va_end(va);
1226 			return buf;
1227 		}
1228 	case 'K':
1229 		/*
1230 		 * %pK cannot be used in IRQ context because its test
1231 		 * for CAP_SYSLOG would be meaningless.
1232 		 */
1233 		if (kptr_restrict && (in_irq() || in_serving_softirq() ||
1234 				      in_nmi())) {
1235 			if (spec.field_width == -1)
1236 				spec.field_width = default_width;
1237 			return string(buf, end, "pK-error", spec);
1238 		}
1239 		if (!((kptr_restrict == 0) ||
1240 		      (kptr_restrict == 1 &&
1241 		       has_capability_noaudit(current, CAP_SYSLOG))))
1242 			ptr = NULL;
1243 		break;
1244 	case 'N':
1245 		switch (fmt[1]) {
1246 		case 'F':
1247 			return netdev_feature_string(buf, end, ptr, spec);
1248 		}
1249 		break;
1250 	case 'a':
1251 		spec.flags |= SPECIAL | SMALL | ZEROPAD;
1252 		spec.field_width = sizeof(phys_addr_t) * 2 + 2;
1253 		spec.base = 16;
1254 		return number(buf, end,
1255 			      (unsigned long long) *((phys_addr_t *)ptr), spec);
1256 	}
1257 	spec.flags |= SMALL;
1258 	if (spec.field_width == -1) {
1259 		spec.field_width = default_width;
1260 		spec.flags |= ZEROPAD;
1261 	}
1262 	spec.base = 16;
1263 
1264 	return number(buf, end, (unsigned long) ptr, spec);
1265 }
1266 
1267 /*
1268  * Helper function to decode printf style format.
1269  * Each call decode a token from the format and return the
1270  * number of characters read (or likely the delta where it wants
1271  * to go on the next call).
1272  * The decoded token is returned through the parameters
1273  *
1274  * 'h', 'l', or 'L' for integer fields
1275  * 'z' support added 23/7/1999 S.H.
1276  * 'z' changed to 'Z' --davidm 1/25/99
1277  * 't' added for ptrdiff_t
1278  *
1279  * @fmt: the format string
1280  * @type of the token returned
1281  * @flags: various flags such as +, -, # tokens..
1282  * @field_width: overwritten width
1283  * @base: base of the number (octal, hex, ...)
1284  * @precision: precision of a number
1285  * @qualifier: qualifier of a number (long, size_t, ...)
1286  */
1287 static noinline_for_stack
1288 int format_decode(const char *fmt, struct printf_spec *spec)
1289 {
1290 	const char *start = fmt;
1291 
1292 	/* we finished early by reading the field width */
1293 	if (spec->type == FORMAT_TYPE_WIDTH) {
1294 		if (spec->field_width < 0) {
1295 			spec->field_width = -spec->field_width;
1296 			spec->flags |= LEFT;
1297 		}
1298 		spec->type = FORMAT_TYPE_NONE;
1299 		goto precision;
1300 	}
1301 
1302 	/* we finished early by reading the precision */
1303 	if (spec->type == FORMAT_TYPE_PRECISION) {
1304 		if (spec->precision < 0)
1305 			spec->precision = 0;
1306 
1307 		spec->type = FORMAT_TYPE_NONE;
1308 		goto qualifier;
1309 	}
1310 
1311 	/* By default */
1312 	spec->type = FORMAT_TYPE_NONE;
1313 
1314 	for (; *fmt ; ++fmt) {
1315 		if (*fmt == '%')
1316 			break;
1317 	}
1318 
1319 	/* Return the current non-format string */
1320 	if (fmt != start || !*fmt)
1321 		return fmt - start;
1322 
1323 	/* Process flags */
1324 	spec->flags = 0;
1325 
1326 	while (1) { /* this also skips first '%' */
1327 		bool found = true;
1328 
1329 		++fmt;
1330 
1331 		switch (*fmt) {
1332 		case '-': spec->flags |= LEFT;    break;
1333 		case '+': spec->flags |= PLUS;    break;
1334 		case ' ': spec->flags |= SPACE;   break;
1335 		case '#': spec->flags |= SPECIAL; break;
1336 		case '0': spec->flags |= ZEROPAD; break;
1337 		default:  found = false;
1338 		}
1339 
1340 		if (!found)
1341 			break;
1342 	}
1343 
1344 	/* get field width */
1345 	spec->field_width = -1;
1346 
1347 	if (isdigit(*fmt))
1348 		spec->field_width = skip_atoi(&fmt);
1349 	else if (*fmt == '*') {
1350 		/* it's the next argument */
1351 		spec->type = FORMAT_TYPE_WIDTH;
1352 		return ++fmt - start;
1353 	}
1354 
1355 precision:
1356 	/* get the precision */
1357 	spec->precision = -1;
1358 	if (*fmt == '.') {
1359 		++fmt;
1360 		if (isdigit(*fmt)) {
1361 			spec->precision = skip_atoi(&fmt);
1362 			if (spec->precision < 0)
1363 				spec->precision = 0;
1364 		} else if (*fmt == '*') {
1365 			/* it's the next argument */
1366 			spec->type = FORMAT_TYPE_PRECISION;
1367 			return ++fmt - start;
1368 		}
1369 	}
1370 
1371 qualifier:
1372 	/* get the conversion qualifier */
1373 	spec->qualifier = -1;
1374 	if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1375 	    _tolower(*fmt) == 'z' || *fmt == 't') {
1376 		spec->qualifier = *fmt++;
1377 		if (unlikely(spec->qualifier == *fmt)) {
1378 			if (spec->qualifier == 'l') {
1379 				spec->qualifier = 'L';
1380 				++fmt;
1381 			} else if (spec->qualifier == 'h') {
1382 				spec->qualifier = 'H';
1383 				++fmt;
1384 			}
1385 		}
1386 	}
1387 
1388 	/* default base */
1389 	spec->base = 10;
1390 	switch (*fmt) {
1391 	case 'c':
1392 		spec->type = FORMAT_TYPE_CHAR;
1393 		return ++fmt - start;
1394 
1395 	case 's':
1396 		spec->type = FORMAT_TYPE_STR;
1397 		return ++fmt - start;
1398 
1399 	case 'p':
1400 		spec->type = FORMAT_TYPE_PTR;
1401 		return fmt - start;
1402 		/* skip alnum */
1403 
1404 	case 'n':
1405 		spec->type = FORMAT_TYPE_NRCHARS;
1406 		return ++fmt - start;
1407 
1408 	case '%':
1409 		spec->type = FORMAT_TYPE_PERCENT_CHAR;
1410 		return ++fmt - start;
1411 
1412 	/* integer number formats - set up the flags and "break" */
1413 	case 'o':
1414 		spec->base = 8;
1415 		break;
1416 
1417 	case 'x':
1418 		spec->flags |= SMALL;
1419 
1420 	case 'X':
1421 		spec->base = 16;
1422 		break;
1423 
1424 	case 'd':
1425 	case 'i':
1426 		spec->flags |= SIGN;
1427 	case 'u':
1428 		break;
1429 
1430 	default:
1431 		spec->type = FORMAT_TYPE_INVALID;
1432 		return fmt - start;
1433 	}
1434 
1435 	if (spec->qualifier == 'L')
1436 		spec->type = FORMAT_TYPE_LONG_LONG;
1437 	else if (spec->qualifier == 'l') {
1438 		if (spec->flags & SIGN)
1439 			spec->type = FORMAT_TYPE_LONG;
1440 		else
1441 			spec->type = FORMAT_TYPE_ULONG;
1442 	} else if (_tolower(spec->qualifier) == 'z') {
1443 		spec->type = FORMAT_TYPE_SIZE_T;
1444 	} else if (spec->qualifier == 't') {
1445 		spec->type = FORMAT_TYPE_PTRDIFF;
1446 	} else if (spec->qualifier == 'H') {
1447 		if (spec->flags & SIGN)
1448 			spec->type = FORMAT_TYPE_BYTE;
1449 		else
1450 			spec->type = FORMAT_TYPE_UBYTE;
1451 	} else if (spec->qualifier == 'h') {
1452 		if (spec->flags & SIGN)
1453 			spec->type = FORMAT_TYPE_SHORT;
1454 		else
1455 			spec->type = FORMAT_TYPE_USHORT;
1456 	} else {
1457 		if (spec->flags & SIGN)
1458 			spec->type = FORMAT_TYPE_INT;
1459 		else
1460 			spec->type = FORMAT_TYPE_UINT;
1461 	}
1462 
1463 	return ++fmt - start;
1464 }
1465 
1466 /**
1467  * vsnprintf - Format a string and place it in a buffer
1468  * @buf: The buffer to place the result into
1469  * @size: The size of the buffer, including the trailing null space
1470  * @fmt: The format string to use
1471  * @args: Arguments for the format string
1472  *
1473  * This function follows C99 vsnprintf, but has some extensions:
1474  * %pS output the name of a text symbol with offset
1475  * %ps output the name of a text symbol without offset
1476  * %pF output the name of a function pointer with its offset
1477  * %pf output the name of a function pointer without its offset
1478  * %pB output the name of a backtrace symbol with its offset
1479  * %pR output the address range in a struct resource with decoded flags
1480  * %pr output the address range in a struct resource with raw flags
1481  * %pM output a 6-byte MAC address with colons
1482  * %pMR output a 6-byte MAC address with colons in reversed order
1483  * %pMF output a 6-byte MAC address with dashes
1484  * %pm output a 6-byte MAC address without colons
1485  * %pmR output a 6-byte MAC address without colons in reversed order
1486  * %pI4 print an IPv4 address without leading zeros
1487  * %pi4 print an IPv4 address with leading zeros
1488  * %pI6 print an IPv6 address with colons
1489  * %pi6 print an IPv6 address without colons
1490  * %pI6c print an IPv6 address as specified by RFC 5952
1491  * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1492  * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1493  * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1494  *   case.
1495  * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1496  *           bytes of the input)
1497  * %n is ignored
1498  *
1499  * ** Please update Documentation/printk-formats.txt when making changes **
1500  *
1501  * The return value is the number of characters which would
1502  * be generated for the given input, excluding the trailing
1503  * '\0', as per ISO C99. If you want to have the exact
1504  * number of characters written into @buf as return value
1505  * (not including the trailing '\0'), use vscnprintf(). If the
1506  * return is greater than or equal to @size, the resulting
1507  * string is truncated.
1508  *
1509  * If you're not already dealing with a va_list consider using snprintf().
1510  */
1511 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1512 {
1513 	unsigned long long num;
1514 	char *str, *end;
1515 	struct printf_spec spec = {0};
1516 
1517 	/* Reject out-of-range values early.  Large positive sizes are
1518 	   used for unknown buffer sizes. */
1519 	if (WARN_ON_ONCE((int) size < 0))
1520 		return 0;
1521 
1522 	str = buf;
1523 	end = buf + size;
1524 
1525 	/* Make sure end is always >= buf */
1526 	if (end < buf) {
1527 		end = ((void *)-1);
1528 		size = end - buf;
1529 	}
1530 
1531 	while (*fmt) {
1532 		const char *old_fmt = fmt;
1533 		int read = format_decode(fmt, &spec);
1534 
1535 		fmt += read;
1536 
1537 		switch (spec.type) {
1538 		case FORMAT_TYPE_NONE: {
1539 			int copy = read;
1540 			if (str < end) {
1541 				if (copy > end - str)
1542 					copy = end - str;
1543 				memcpy(str, old_fmt, copy);
1544 			}
1545 			str += read;
1546 			break;
1547 		}
1548 
1549 		case FORMAT_TYPE_WIDTH:
1550 			spec.field_width = va_arg(args, int);
1551 			break;
1552 
1553 		case FORMAT_TYPE_PRECISION:
1554 			spec.precision = va_arg(args, int);
1555 			break;
1556 
1557 		case FORMAT_TYPE_CHAR: {
1558 			char c;
1559 
1560 			if (!(spec.flags & LEFT)) {
1561 				while (--spec.field_width > 0) {
1562 					if (str < end)
1563 						*str = ' ';
1564 					++str;
1565 
1566 				}
1567 			}
1568 			c = (unsigned char) va_arg(args, int);
1569 			if (str < end)
1570 				*str = c;
1571 			++str;
1572 			while (--spec.field_width > 0) {
1573 				if (str < end)
1574 					*str = ' ';
1575 				++str;
1576 			}
1577 			break;
1578 		}
1579 
1580 		case FORMAT_TYPE_STR:
1581 			str = string(str, end, va_arg(args, char *), spec);
1582 			break;
1583 
1584 		case FORMAT_TYPE_PTR:
1585 			str = pointer(fmt+1, str, end, va_arg(args, void *),
1586 				      spec);
1587 			while (isalnum(*fmt))
1588 				fmt++;
1589 			break;
1590 
1591 		case FORMAT_TYPE_PERCENT_CHAR:
1592 			if (str < end)
1593 				*str = '%';
1594 			++str;
1595 			break;
1596 
1597 		case FORMAT_TYPE_INVALID:
1598 			if (str < end)
1599 				*str = '%';
1600 			++str;
1601 			break;
1602 
1603 		case FORMAT_TYPE_NRCHARS: {
1604 			u8 qualifier = spec.qualifier;
1605 
1606 			if (qualifier == 'l') {
1607 				long *ip = va_arg(args, long *);
1608 				*ip = (str - buf);
1609 			} else if (_tolower(qualifier) == 'z') {
1610 				size_t *ip = va_arg(args, size_t *);
1611 				*ip = (str - buf);
1612 			} else {
1613 				int *ip = va_arg(args, int *);
1614 				*ip = (str - buf);
1615 			}
1616 			break;
1617 		}
1618 
1619 		default:
1620 			switch (spec.type) {
1621 			case FORMAT_TYPE_LONG_LONG:
1622 				num = va_arg(args, long long);
1623 				break;
1624 			case FORMAT_TYPE_ULONG:
1625 				num = va_arg(args, unsigned long);
1626 				break;
1627 			case FORMAT_TYPE_LONG:
1628 				num = va_arg(args, long);
1629 				break;
1630 			case FORMAT_TYPE_SIZE_T:
1631 				if (spec.flags & SIGN)
1632 					num = va_arg(args, ssize_t);
1633 				else
1634 					num = va_arg(args, size_t);
1635 				break;
1636 			case FORMAT_TYPE_PTRDIFF:
1637 				num = va_arg(args, ptrdiff_t);
1638 				break;
1639 			case FORMAT_TYPE_UBYTE:
1640 				num = (unsigned char) va_arg(args, int);
1641 				break;
1642 			case FORMAT_TYPE_BYTE:
1643 				num = (signed char) va_arg(args, int);
1644 				break;
1645 			case FORMAT_TYPE_USHORT:
1646 				num = (unsigned short) va_arg(args, int);
1647 				break;
1648 			case FORMAT_TYPE_SHORT:
1649 				num = (short) va_arg(args, int);
1650 				break;
1651 			case FORMAT_TYPE_INT:
1652 				num = (int) va_arg(args, int);
1653 				break;
1654 			default:
1655 				num = va_arg(args, unsigned int);
1656 			}
1657 
1658 			str = number(str, end, num, spec);
1659 		}
1660 	}
1661 
1662 	if (size > 0) {
1663 		if (str < end)
1664 			*str = '\0';
1665 		else
1666 			end[-1] = '\0';
1667 	}
1668 
1669 	/* the trailing null byte doesn't count towards the total */
1670 	return str-buf;
1671 
1672 }
1673 EXPORT_SYMBOL(vsnprintf);
1674 
1675 /**
1676  * vscnprintf - Format a string and place it in a buffer
1677  * @buf: The buffer to place the result into
1678  * @size: The size of the buffer, including the trailing null space
1679  * @fmt: The format string to use
1680  * @args: Arguments for the format string
1681  *
1682  * The return value is the number of characters which have been written into
1683  * the @buf not including the trailing '\0'. If @size is == 0 the function
1684  * returns 0.
1685  *
1686  * If you're not already dealing with a va_list consider using scnprintf().
1687  *
1688  * See the vsnprintf() documentation for format string extensions over C99.
1689  */
1690 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1691 {
1692 	int i;
1693 
1694 	i = vsnprintf(buf, size, fmt, args);
1695 
1696 	if (likely(i < size))
1697 		return i;
1698 	if (size != 0)
1699 		return size - 1;
1700 	return 0;
1701 }
1702 EXPORT_SYMBOL(vscnprintf);
1703 
1704 /**
1705  * snprintf - Format a string and place it in a buffer
1706  * @buf: The buffer to place the result into
1707  * @size: The size of the buffer, including the trailing null space
1708  * @fmt: The format string to use
1709  * @...: Arguments for the format string
1710  *
1711  * The return value is the number of characters which would be
1712  * generated for the given input, excluding the trailing null,
1713  * as per ISO C99.  If the return is greater than or equal to
1714  * @size, the resulting string is truncated.
1715  *
1716  * See the vsnprintf() documentation for format string extensions over C99.
1717  */
1718 int snprintf(char *buf, size_t size, const char *fmt, ...)
1719 {
1720 	va_list args;
1721 	int i;
1722 
1723 	va_start(args, fmt);
1724 	i = vsnprintf(buf, size, fmt, args);
1725 	va_end(args);
1726 
1727 	return i;
1728 }
1729 EXPORT_SYMBOL(snprintf);
1730 
1731 /**
1732  * scnprintf - Format a string and place it in a buffer
1733  * @buf: The buffer to place the result into
1734  * @size: The size of the buffer, including the trailing null space
1735  * @fmt: The format string to use
1736  * @...: Arguments for the format string
1737  *
1738  * The return value is the number of characters written into @buf not including
1739  * the trailing '\0'. If @size is == 0 the function returns 0.
1740  */
1741 
1742 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1743 {
1744 	va_list args;
1745 	int i;
1746 
1747 	va_start(args, fmt);
1748 	i = vscnprintf(buf, size, fmt, args);
1749 	va_end(args);
1750 
1751 	return i;
1752 }
1753 EXPORT_SYMBOL(scnprintf);
1754 
1755 /**
1756  * vsprintf - Format a string and place it in a buffer
1757  * @buf: The buffer to place the result into
1758  * @fmt: The format string to use
1759  * @args: Arguments for the format string
1760  *
1761  * The function returns the number of characters written
1762  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1763  * buffer overflows.
1764  *
1765  * If you're not already dealing with a va_list consider using sprintf().
1766  *
1767  * See the vsnprintf() documentation for format string extensions over C99.
1768  */
1769 int vsprintf(char *buf, const char *fmt, va_list args)
1770 {
1771 	return vsnprintf(buf, INT_MAX, fmt, args);
1772 }
1773 EXPORT_SYMBOL(vsprintf);
1774 
1775 /**
1776  * sprintf - Format a string and place it in a buffer
1777  * @buf: The buffer to place the result into
1778  * @fmt: The format string to use
1779  * @...: Arguments for the format string
1780  *
1781  * The function returns the number of characters written
1782  * into @buf. Use snprintf() or scnprintf() in order to avoid
1783  * buffer overflows.
1784  *
1785  * See the vsnprintf() documentation for format string extensions over C99.
1786  */
1787 int sprintf(char *buf, const char *fmt, ...)
1788 {
1789 	va_list args;
1790 	int i;
1791 
1792 	va_start(args, fmt);
1793 	i = vsnprintf(buf, INT_MAX, fmt, args);
1794 	va_end(args);
1795 
1796 	return i;
1797 }
1798 EXPORT_SYMBOL(sprintf);
1799 
1800 #ifdef CONFIG_BINARY_PRINTF
1801 /*
1802  * bprintf service:
1803  * vbin_printf() - VA arguments to binary data
1804  * bstr_printf() - Binary data to text string
1805  */
1806 
1807 /**
1808  * vbin_printf - Parse a format string and place args' binary value in a buffer
1809  * @bin_buf: The buffer to place args' binary value
1810  * @size: The size of the buffer(by words(32bits), not characters)
1811  * @fmt: The format string to use
1812  * @args: Arguments for the format string
1813  *
1814  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1815  * is skiped.
1816  *
1817  * The return value is the number of words(32bits) which would be generated for
1818  * the given input.
1819  *
1820  * NOTE:
1821  * If the return value is greater than @size, the resulting bin_buf is NOT
1822  * valid for bstr_printf().
1823  */
1824 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1825 {
1826 	struct printf_spec spec = {0};
1827 	char *str, *end;
1828 
1829 	str = (char *)bin_buf;
1830 	end = (char *)(bin_buf + size);
1831 
1832 #define save_arg(type)							\
1833 do {									\
1834 	if (sizeof(type) == 8) {					\
1835 		unsigned long long value;				\
1836 		str = PTR_ALIGN(str, sizeof(u32));			\
1837 		value = va_arg(args, unsigned long long);		\
1838 		if (str + sizeof(type) <= end) {			\
1839 			*(u32 *)str = *(u32 *)&value;			\
1840 			*(u32 *)(str + 4) = *((u32 *)&value + 1);	\
1841 		}							\
1842 	} else {							\
1843 		unsigned long value;					\
1844 		str = PTR_ALIGN(str, sizeof(type));			\
1845 		value = va_arg(args, int);				\
1846 		if (str + sizeof(type) <= end)				\
1847 			*(typeof(type) *)str = (type)value;		\
1848 	}								\
1849 	str += sizeof(type);						\
1850 } while (0)
1851 
1852 	while (*fmt) {
1853 		int read = format_decode(fmt, &spec);
1854 
1855 		fmt += read;
1856 
1857 		switch (spec.type) {
1858 		case FORMAT_TYPE_NONE:
1859 		case FORMAT_TYPE_INVALID:
1860 		case FORMAT_TYPE_PERCENT_CHAR:
1861 			break;
1862 
1863 		case FORMAT_TYPE_WIDTH:
1864 		case FORMAT_TYPE_PRECISION:
1865 			save_arg(int);
1866 			break;
1867 
1868 		case FORMAT_TYPE_CHAR:
1869 			save_arg(char);
1870 			break;
1871 
1872 		case FORMAT_TYPE_STR: {
1873 			const char *save_str = va_arg(args, char *);
1874 			size_t len;
1875 
1876 			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1877 					|| (unsigned long)save_str < PAGE_SIZE)
1878 				save_str = "(null)";
1879 			len = strlen(save_str) + 1;
1880 			if (str + len < end)
1881 				memcpy(str, save_str, len);
1882 			str += len;
1883 			break;
1884 		}
1885 
1886 		case FORMAT_TYPE_PTR:
1887 			save_arg(void *);
1888 			/* skip all alphanumeric pointer suffixes */
1889 			while (isalnum(*fmt))
1890 				fmt++;
1891 			break;
1892 
1893 		case FORMAT_TYPE_NRCHARS: {
1894 			/* skip %n 's argument */
1895 			u8 qualifier = spec.qualifier;
1896 			void *skip_arg;
1897 			if (qualifier == 'l')
1898 				skip_arg = va_arg(args, long *);
1899 			else if (_tolower(qualifier) == 'z')
1900 				skip_arg = va_arg(args, size_t *);
1901 			else
1902 				skip_arg = va_arg(args, int *);
1903 			break;
1904 		}
1905 
1906 		default:
1907 			switch (spec.type) {
1908 
1909 			case FORMAT_TYPE_LONG_LONG:
1910 				save_arg(long long);
1911 				break;
1912 			case FORMAT_TYPE_ULONG:
1913 			case FORMAT_TYPE_LONG:
1914 				save_arg(unsigned long);
1915 				break;
1916 			case FORMAT_TYPE_SIZE_T:
1917 				save_arg(size_t);
1918 				break;
1919 			case FORMAT_TYPE_PTRDIFF:
1920 				save_arg(ptrdiff_t);
1921 				break;
1922 			case FORMAT_TYPE_UBYTE:
1923 			case FORMAT_TYPE_BYTE:
1924 				save_arg(char);
1925 				break;
1926 			case FORMAT_TYPE_USHORT:
1927 			case FORMAT_TYPE_SHORT:
1928 				save_arg(short);
1929 				break;
1930 			default:
1931 				save_arg(int);
1932 			}
1933 		}
1934 	}
1935 
1936 	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1937 #undef save_arg
1938 }
1939 EXPORT_SYMBOL_GPL(vbin_printf);
1940 
1941 /**
1942  * bstr_printf - Format a string from binary arguments and place it in a buffer
1943  * @buf: The buffer to place the result into
1944  * @size: The size of the buffer, including the trailing null space
1945  * @fmt: The format string to use
1946  * @bin_buf: Binary arguments for the format string
1947  *
1948  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1949  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1950  * a binary buffer that generated by vbin_printf.
1951  *
1952  * The format follows C99 vsnprintf, but has some extensions:
1953  *  see vsnprintf comment for details.
1954  *
1955  * The return value is the number of characters which would
1956  * be generated for the given input, excluding the trailing
1957  * '\0', as per ISO C99. If you want to have the exact
1958  * number of characters written into @buf as return value
1959  * (not including the trailing '\0'), use vscnprintf(). If the
1960  * return is greater than or equal to @size, the resulting
1961  * string is truncated.
1962  */
1963 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1964 {
1965 	struct printf_spec spec = {0};
1966 	char *str, *end;
1967 	const char *args = (const char *)bin_buf;
1968 
1969 	if (WARN_ON_ONCE((int) size < 0))
1970 		return 0;
1971 
1972 	str = buf;
1973 	end = buf + size;
1974 
1975 #define get_arg(type)							\
1976 ({									\
1977 	typeof(type) value;						\
1978 	if (sizeof(type) == 8) {					\
1979 		args = PTR_ALIGN(args, sizeof(u32));			\
1980 		*(u32 *)&value = *(u32 *)args;				\
1981 		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
1982 	} else {							\
1983 		args = PTR_ALIGN(args, sizeof(type));			\
1984 		value = *(typeof(type) *)args;				\
1985 	}								\
1986 	args += sizeof(type);						\
1987 	value;								\
1988 })
1989 
1990 	/* Make sure end is always >= buf */
1991 	if (end < buf) {
1992 		end = ((void *)-1);
1993 		size = end - buf;
1994 	}
1995 
1996 	while (*fmt) {
1997 		const char *old_fmt = fmt;
1998 		int read = format_decode(fmt, &spec);
1999 
2000 		fmt += read;
2001 
2002 		switch (spec.type) {
2003 		case FORMAT_TYPE_NONE: {
2004 			int copy = read;
2005 			if (str < end) {
2006 				if (copy > end - str)
2007 					copy = end - str;
2008 				memcpy(str, old_fmt, copy);
2009 			}
2010 			str += read;
2011 			break;
2012 		}
2013 
2014 		case FORMAT_TYPE_WIDTH:
2015 			spec.field_width = get_arg(int);
2016 			break;
2017 
2018 		case FORMAT_TYPE_PRECISION:
2019 			spec.precision = get_arg(int);
2020 			break;
2021 
2022 		case FORMAT_TYPE_CHAR: {
2023 			char c;
2024 
2025 			if (!(spec.flags & LEFT)) {
2026 				while (--spec.field_width > 0) {
2027 					if (str < end)
2028 						*str = ' ';
2029 					++str;
2030 				}
2031 			}
2032 			c = (unsigned char) get_arg(char);
2033 			if (str < end)
2034 				*str = c;
2035 			++str;
2036 			while (--spec.field_width > 0) {
2037 				if (str < end)
2038 					*str = ' ';
2039 				++str;
2040 			}
2041 			break;
2042 		}
2043 
2044 		case FORMAT_TYPE_STR: {
2045 			const char *str_arg = args;
2046 			args += strlen(str_arg) + 1;
2047 			str = string(str, end, (char *)str_arg, spec);
2048 			break;
2049 		}
2050 
2051 		case FORMAT_TYPE_PTR:
2052 			str = pointer(fmt+1, str, end, get_arg(void *), spec);
2053 			while (isalnum(*fmt))
2054 				fmt++;
2055 			break;
2056 
2057 		case FORMAT_TYPE_PERCENT_CHAR:
2058 		case FORMAT_TYPE_INVALID:
2059 			if (str < end)
2060 				*str = '%';
2061 			++str;
2062 			break;
2063 
2064 		case FORMAT_TYPE_NRCHARS:
2065 			/* skip */
2066 			break;
2067 
2068 		default: {
2069 			unsigned long long num;
2070 
2071 			switch (spec.type) {
2072 
2073 			case FORMAT_TYPE_LONG_LONG:
2074 				num = get_arg(long long);
2075 				break;
2076 			case FORMAT_TYPE_ULONG:
2077 			case FORMAT_TYPE_LONG:
2078 				num = get_arg(unsigned long);
2079 				break;
2080 			case FORMAT_TYPE_SIZE_T:
2081 				num = get_arg(size_t);
2082 				break;
2083 			case FORMAT_TYPE_PTRDIFF:
2084 				num = get_arg(ptrdiff_t);
2085 				break;
2086 			case FORMAT_TYPE_UBYTE:
2087 				num = get_arg(unsigned char);
2088 				break;
2089 			case FORMAT_TYPE_BYTE:
2090 				num = get_arg(signed char);
2091 				break;
2092 			case FORMAT_TYPE_USHORT:
2093 				num = get_arg(unsigned short);
2094 				break;
2095 			case FORMAT_TYPE_SHORT:
2096 				num = get_arg(short);
2097 				break;
2098 			case FORMAT_TYPE_UINT:
2099 				num = get_arg(unsigned int);
2100 				break;
2101 			default:
2102 				num = get_arg(int);
2103 			}
2104 
2105 			str = number(str, end, num, spec);
2106 		} /* default: */
2107 		} /* switch(spec.type) */
2108 	} /* while(*fmt) */
2109 
2110 	if (size > 0) {
2111 		if (str < end)
2112 			*str = '\0';
2113 		else
2114 			end[-1] = '\0';
2115 	}
2116 
2117 #undef get_arg
2118 
2119 	/* the trailing null byte doesn't count towards the total */
2120 	return str - buf;
2121 }
2122 EXPORT_SYMBOL_GPL(bstr_printf);
2123 
2124 /**
2125  * bprintf - Parse a format string and place args' binary value in a buffer
2126  * @bin_buf: The buffer to place args' binary value
2127  * @size: The size of the buffer(by words(32bits), not characters)
2128  * @fmt: The format string to use
2129  * @...: Arguments for the format string
2130  *
2131  * The function returns the number of words(u32) written
2132  * into @bin_buf.
2133  */
2134 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2135 {
2136 	va_list args;
2137 	int ret;
2138 
2139 	va_start(args, fmt);
2140 	ret = vbin_printf(bin_buf, size, fmt, args);
2141 	va_end(args);
2142 
2143 	return ret;
2144 }
2145 EXPORT_SYMBOL_GPL(bprintf);
2146 
2147 #endif /* CONFIG_BINARY_PRINTF */
2148 
2149 /**
2150  * vsscanf - Unformat a buffer into a list of arguments
2151  * @buf:	input buffer
2152  * @fmt:	format of buffer
2153  * @args:	arguments
2154  */
2155 int vsscanf(const char *buf, const char *fmt, va_list args)
2156 {
2157 	const char *str = buf;
2158 	char *next;
2159 	char digit;
2160 	int num = 0;
2161 	u8 qualifier;
2162 	unsigned int base;
2163 	union {
2164 		long long s;
2165 		unsigned long long u;
2166 	} val;
2167 	s16 field_width;
2168 	bool is_sign;
2169 
2170 	while (*fmt) {
2171 		/* skip any white space in format */
2172 		/* white space in format matchs any amount of
2173 		 * white space, including none, in the input.
2174 		 */
2175 		if (isspace(*fmt)) {
2176 			fmt = skip_spaces(++fmt);
2177 			str = skip_spaces(str);
2178 		}
2179 
2180 		/* anything that is not a conversion must match exactly */
2181 		if (*fmt != '%' && *fmt) {
2182 			if (*fmt++ != *str++)
2183 				break;
2184 			continue;
2185 		}
2186 
2187 		if (!*fmt)
2188 			break;
2189 		++fmt;
2190 
2191 		/* skip this conversion.
2192 		 * advance both strings to next white space
2193 		 */
2194 		if (*fmt == '*') {
2195 			if (!*str)
2196 				break;
2197 			while (!isspace(*fmt) && *fmt != '%' && *fmt)
2198 				fmt++;
2199 			while (!isspace(*str) && *str)
2200 				str++;
2201 			continue;
2202 		}
2203 
2204 		/* get field width */
2205 		field_width = -1;
2206 		if (isdigit(*fmt)) {
2207 			field_width = skip_atoi(&fmt);
2208 			if (field_width <= 0)
2209 				break;
2210 		}
2211 
2212 		/* get conversion qualifier */
2213 		qualifier = -1;
2214 		if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2215 		    _tolower(*fmt) == 'z') {
2216 			qualifier = *fmt++;
2217 			if (unlikely(qualifier == *fmt)) {
2218 				if (qualifier == 'h') {
2219 					qualifier = 'H';
2220 					fmt++;
2221 				} else if (qualifier == 'l') {
2222 					qualifier = 'L';
2223 					fmt++;
2224 				}
2225 			}
2226 		}
2227 
2228 		if (!*fmt)
2229 			break;
2230 
2231 		if (*fmt == 'n') {
2232 			/* return number of characters read so far */
2233 			*va_arg(args, int *) = str - buf;
2234 			++fmt;
2235 			continue;
2236 		}
2237 
2238 		if (!*str)
2239 			break;
2240 
2241 		base = 10;
2242 		is_sign = 0;
2243 
2244 		switch (*fmt++) {
2245 		case 'c':
2246 		{
2247 			char *s = (char *)va_arg(args, char*);
2248 			if (field_width == -1)
2249 				field_width = 1;
2250 			do {
2251 				*s++ = *str++;
2252 			} while (--field_width > 0 && *str);
2253 			num++;
2254 		}
2255 		continue;
2256 		case 's':
2257 		{
2258 			char *s = (char *)va_arg(args, char *);
2259 			if (field_width == -1)
2260 				field_width = SHRT_MAX;
2261 			/* first, skip leading white space in buffer */
2262 			str = skip_spaces(str);
2263 
2264 			/* now copy until next white space */
2265 			while (*str && !isspace(*str) && field_width--)
2266 				*s++ = *str++;
2267 			*s = '\0';
2268 			num++;
2269 		}
2270 		continue;
2271 		case 'o':
2272 			base = 8;
2273 			break;
2274 		case 'x':
2275 		case 'X':
2276 			base = 16;
2277 			break;
2278 		case 'i':
2279 			base = 0;
2280 		case 'd':
2281 			is_sign = 1;
2282 		case 'u':
2283 			break;
2284 		case '%':
2285 			/* looking for '%' in str */
2286 			if (*str++ != '%')
2287 				return num;
2288 			continue;
2289 		default:
2290 			/* invalid format; stop here */
2291 			return num;
2292 		}
2293 
2294 		/* have some sort of integer conversion.
2295 		 * first, skip white space in buffer.
2296 		 */
2297 		str = skip_spaces(str);
2298 
2299 		digit = *str;
2300 		if (is_sign && digit == '-')
2301 			digit = *(str + 1);
2302 
2303 		if (!digit
2304 		    || (base == 16 && !isxdigit(digit))
2305 		    || (base == 10 && !isdigit(digit))
2306 		    || (base == 8 && (!isdigit(digit) || digit > '7'))
2307 		    || (base == 0 && !isdigit(digit)))
2308 			break;
2309 
2310 		if (is_sign)
2311 			val.s = qualifier != 'L' ?
2312 				simple_strtol(str, &next, base) :
2313 				simple_strtoll(str, &next, base);
2314 		else
2315 			val.u = qualifier != 'L' ?
2316 				simple_strtoul(str, &next, base) :
2317 				simple_strtoull(str, &next, base);
2318 
2319 		if (field_width > 0 && next - str > field_width) {
2320 			if (base == 0)
2321 				_parse_integer_fixup_radix(str, &base);
2322 			while (next - str > field_width) {
2323 				if (is_sign)
2324 					val.s = div_s64(val.s, base);
2325 				else
2326 					val.u = div_u64(val.u, base);
2327 				--next;
2328 			}
2329 		}
2330 
2331 		switch (qualifier) {
2332 		case 'H':	/* that's 'hh' in format */
2333 			if (is_sign)
2334 				*va_arg(args, signed char *) = val.s;
2335 			else
2336 				*va_arg(args, unsigned char *) = val.u;
2337 			break;
2338 		case 'h':
2339 			if (is_sign)
2340 				*va_arg(args, short *) = val.s;
2341 			else
2342 				*va_arg(args, unsigned short *) = val.u;
2343 			break;
2344 		case 'l':
2345 			if (is_sign)
2346 				*va_arg(args, long *) = val.s;
2347 			else
2348 				*va_arg(args, unsigned long *) = val.u;
2349 			break;
2350 		case 'L':
2351 			if (is_sign)
2352 				*va_arg(args, long long *) = val.s;
2353 			else
2354 				*va_arg(args, unsigned long long *) = val.u;
2355 			break;
2356 		case 'Z':
2357 		case 'z':
2358 			*va_arg(args, size_t *) = val.u;
2359 			break;
2360 		default:
2361 			if (is_sign)
2362 				*va_arg(args, int *) = val.s;
2363 			else
2364 				*va_arg(args, unsigned int *) = val.u;
2365 			break;
2366 		}
2367 		num++;
2368 
2369 		if (!next)
2370 			break;
2371 		str = next;
2372 	}
2373 
2374 	return num;
2375 }
2376 EXPORT_SYMBOL(vsscanf);
2377 
2378 /**
2379  * sscanf - Unformat a buffer into a list of arguments
2380  * @buf:	input buffer
2381  * @fmt:	formatting of buffer
2382  * @...:	resulting arguments
2383  */
2384 int sscanf(const char *buf, const char *fmt, ...)
2385 {
2386 	va_list args;
2387 	int i;
2388 
2389 	va_start(args, fmt);
2390 	i = vsscanf(buf, fmt, args);
2391 	va_end(args);
2392 
2393 	return i;
2394 }
2395 EXPORT_SYMBOL(sscanf);
2396