xref: /linux/lib/vsprintf.c (revision 913df4453f85f1fe79b35ecf3c9a0c0b707d22a2)
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>
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/uaccess.h>
27 #include <linux/ioport.h>
28 #include <net/addrconf.h>
29 
30 #include <asm/page.h>		/* for PAGE_SIZE */
31 #include <asm/div64.h>
32 #include <asm/sections.h>	/* for dereference_function_descriptor() */
33 
34 /* Works only for digits and letters, but small and fast */
35 #define TOLOWER(x) ((x) | 0x20)
36 
37 static unsigned int simple_guess_base(const char *cp)
38 {
39 	if (cp[0] == '0') {
40 		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
41 			return 16;
42 		else
43 			return 8;
44 	} else {
45 		return 10;
46 	}
47 }
48 
49 /**
50  * simple_strtoul - convert a string to an unsigned long
51  * @cp: The start of the string
52  * @endp: A pointer to the end of the parsed string will be placed here
53  * @base: The number base to use
54  */
55 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
56 {
57 	unsigned long result = 0;
58 
59 	if (!base)
60 		base = simple_guess_base(cp);
61 
62 	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
63 		cp += 2;
64 
65 	while (isxdigit(*cp)) {
66 		unsigned int value;
67 
68 		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
69 		if (value >= base)
70 			break;
71 		result = result * base + value;
72 		cp++;
73 	}
74 
75 	if (endp)
76 		*endp = (char *)cp;
77 	return result;
78 }
79 EXPORT_SYMBOL(simple_strtoul);
80 
81 /**
82  * simple_strtol - convert a string to a signed long
83  * @cp: The start of the string
84  * @endp: A pointer to the end of the parsed string will be placed here
85  * @base: The number base to use
86  */
87 long simple_strtol(const char *cp, char **endp, unsigned int base)
88 {
89 	if(*cp == '-')
90 		return -simple_strtoul(cp + 1, endp, base);
91 	return simple_strtoul(cp, endp, base);
92 }
93 EXPORT_SYMBOL(simple_strtol);
94 
95 /**
96  * simple_strtoull - convert a string to an unsigned long long
97  * @cp: The start of the string
98  * @endp: A pointer to the end of the parsed string will be placed here
99  * @base: The number base to use
100  */
101 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
102 {
103 	unsigned long long result = 0;
104 
105 	if (!base)
106 		base = simple_guess_base(cp);
107 
108 	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
109 		cp += 2;
110 
111 	while (isxdigit(*cp)) {
112 		unsigned int value;
113 
114 		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
115 		if (value >= base)
116 			break;
117 		result = result * base + value;
118 		cp++;
119 	}
120 
121 	if (endp)
122 		*endp = (char *)cp;
123 	return result;
124 }
125 EXPORT_SYMBOL(simple_strtoull);
126 
127 /**
128  * simple_strtoll - convert a string to a signed long long
129  * @cp: The start of the string
130  * @endp: A pointer to the end of the parsed string will be placed here
131  * @base: The number base to use
132  */
133 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
134 {
135 	if(*cp=='-')
136 		return -simple_strtoull(cp + 1, endp, base);
137 	return simple_strtoull(cp, endp, base);
138 }
139 
140 /**
141  * strict_strtoul - convert a string to an unsigned long strictly
142  * @cp: The string to be converted
143  * @base: The number base to use
144  * @res: The converted result value
145  *
146  * strict_strtoul converts a string to an unsigned long only if the
147  * string is really an unsigned long string, any string containing
148  * any invalid char at the tail will be rejected and -EINVAL is returned,
149  * only a newline char at the tail is acceptible because people generally
150  * change a module parameter in the following way:
151  *
152  * 	echo 1024 > /sys/module/e1000/parameters/copybreak
153  *
154  * echo will append a newline to the tail.
155  *
156  * It returns 0 if conversion is successful and *res is set to the converted
157  * value, otherwise it returns -EINVAL and *res is set to 0.
158  *
159  * simple_strtoul just ignores the successive invalid characters and
160  * return the converted value of prefix part of the string.
161  */
162 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
163 {
164 	char *tail;
165 	unsigned long val;
166 	size_t len;
167 
168 	*res = 0;
169 	len = strlen(cp);
170 	if (len == 0)
171 		return -EINVAL;
172 
173 	val = simple_strtoul(cp, &tail, base);
174 	if (tail == cp)
175 		return -EINVAL;
176 	if ((*tail == '\0') ||
177 		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
178 		*res = val;
179 		return 0;
180 	}
181 
182 	return -EINVAL;
183 }
184 EXPORT_SYMBOL(strict_strtoul);
185 
186 /**
187  * strict_strtol - convert a string to a long strictly
188  * @cp: The string to be converted
189  * @base: The number base to use
190  * @res: The converted result value
191  *
192  * strict_strtol is similiar to strict_strtoul, but it allows the first
193  * character of a string is '-'.
194  *
195  * It returns 0 if conversion is successful and *res is set to the converted
196  * value, otherwise it returns -EINVAL and *res is set to 0.
197  */
198 int strict_strtol(const char *cp, unsigned int base, long *res)
199 {
200 	int ret;
201 	if (*cp == '-') {
202 		ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
203 		if (!ret)
204 			*res = -(*res);
205 	} else {
206 		ret = strict_strtoul(cp, base, (unsigned long *)res);
207 	}
208 
209 	return ret;
210 }
211 EXPORT_SYMBOL(strict_strtol);
212 
213 /**
214  * strict_strtoull - convert a string to an unsigned long long strictly
215  * @cp: The string to be converted
216  * @base: The number base to use
217  * @res: The converted result value
218  *
219  * strict_strtoull converts a string to an unsigned long long only if the
220  * string is really an unsigned long long string, any string containing
221  * any invalid char at the tail will be rejected and -EINVAL is returned,
222  * only a newline char at the tail is acceptible because people generally
223  * change a module parameter in the following way:
224  *
225  * 	echo 1024 > /sys/module/e1000/parameters/copybreak
226  *
227  * echo will append a newline to the tail of the string.
228  *
229  * It returns 0 if conversion is successful and *res is set to the converted
230  * value, otherwise it returns -EINVAL and *res is set to 0.
231  *
232  * simple_strtoull just ignores the successive invalid characters and
233  * return the converted value of prefix part of the string.
234  */
235 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
236 {
237 	char *tail;
238 	unsigned long long val;
239 	size_t len;
240 
241 	*res = 0;
242 	len = strlen(cp);
243 	if (len == 0)
244 		return -EINVAL;
245 
246 	val = simple_strtoull(cp, &tail, base);
247 	if (tail == cp)
248 		return -EINVAL;
249 	if ((*tail == '\0') ||
250 		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
251 		*res = val;
252 		return 0;
253 	}
254 
255 	return -EINVAL;
256 }
257 EXPORT_SYMBOL(strict_strtoull);
258 
259 /**
260  * strict_strtoll - convert a string to a long long strictly
261  * @cp: The string to be converted
262  * @base: The number base to use
263  * @res: The converted result value
264  *
265  * strict_strtoll is similiar to strict_strtoull, but it allows the first
266  * character of a string is '-'.
267  *
268  * It returns 0 if conversion is successful and *res is set to the converted
269  * value, otherwise it returns -EINVAL and *res is set to 0.
270  */
271 int strict_strtoll(const char *cp, unsigned int base, long long *res)
272 {
273 	int ret;
274 	if (*cp == '-') {
275 		ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
276 		if (!ret)
277 			*res = -(*res);
278 	} else {
279 		ret = strict_strtoull(cp, base, (unsigned long long *)res);
280 	}
281 
282 	return ret;
283 }
284 EXPORT_SYMBOL(strict_strtoll);
285 
286 static int skip_atoi(const char **s)
287 {
288 	int i=0;
289 
290 	while (isdigit(**s))
291 		i = i*10 + *((*s)++) - '0';
292 	return i;
293 }
294 
295 /* Decimal conversion is by far the most typical, and is used
296  * for /proc and /sys data. This directly impacts e.g. top performance
297  * with many processes running. We optimize it for speed
298  * using code from
299  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
300  * (with permission from the author, Douglas W. Jones). */
301 
302 /* Formats correctly any integer in [0,99999].
303  * Outputs from one to five digits depending on input.
304  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
305 static char* put_dec_trunc(char *buf, unsigned q)
306 {
307 	unsigned d3, d2, d1, d0;
308 	d1 = (q>>4) & 0xf;
309 	d2 = (q>>8) & 0xf;
310 	d3 = (q>>12);
311 
312 	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
313 	q = (d0 * 0xcd) >> 11;
314 	d0 = d0 - 10*q;
315 	*buf++ = d0 + '0'; /* least significant digit */
316 	d1 = q + 9*d3 + 5*d2 + d1;
317 	if (d1 != 0) {
318 		q = (d1 * 0xcd) >> 11;
319 		d1 = d1 - 10*q;
320 		*buf++ = d1 + '0'; /* next digit */
321 
322 		d2 = q + 2*d2;
323 		if ((d2 != 0) || (d3 != 0)) {
324 			q = (d2 * 0xd) >> 7;
325 			d2 = d2 - 10*q;
326 			*buf++ = d2 + '0'; /* next digit */
327 
328 			d3 = q + 4*d3;
329 			if (d3 != 0) {
330 				q = (d3 * 0xcd) >> 11;
331 				d3 = d3 - 10*q;
332 				*buf++ = d3 + '0';  /* next digit */
333 				if (q != 0)
334 					*buf++ = q + '0';  /* most sign. digit */
335 			}
336 		}
337 	}
338 	return buf;
339 }
340 /* Same with if's removed. Always emits five digits */
341 static char* put_dec_full(char *buf, unsigned q)
342 {
343 	/* BTW, if q is in [0,9999], 8-bit ints will be enough, */
344 	/* but anyway, gcc produces better code with full-sized ints */
345 	unsigned d3, d2, d1, d0;
346 	d1 = (q>>4) & 0xf;
347 	d2 = (q>>8) & 0xf;
348 	d3 = (q>>12);
349 
350 	/* Possible ways to approx. divide by 10 */
351 	/* gcc -O2 replaces multiply with shifts and adds */
352 	// (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
353 	// (x * 0x67) >> 10:  1100111
354 	// (x * 0x34) >> 9:    110100 - same
355 	// (x * 0x1a) >> 8:     11010 - same
356 	// (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
357 
358 	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
359 	q = (d0 * 0xcd) >> 11;
360 	d0 = d0 - 10*q;
361 	*buf++ = d0 + '0';
362 	d1 = q + 9*d3 + 5*d2 + d1;
363 		q = (d1 * 0xcd) >> 11;
364 		d1 = d1 - 10*q;
365 		*buf++ = d1 + '0';
366 
367 		d2 = q + 2*d2;
368 			q = (d2 * 0xd) >> 7;
369 			d2 = d2 - 10*q;
370 			*buf++ = d2 + '0';
371 
372 			d3 = q + 4*d3;
373 				q = (d3 * 0xcd) >> 11; /* - shorter code */
374 				/* q = (d3 * 0x67) >> 10; - would also work */
375 				d3 = d3 - 10*q;
376 				*buf++ = d3 + '0';
377 					*buf++ = q + '0';
378 	return buf;
379 }
380 /* No inlining helps gcc to use registers better */
381 static noinline char* put_dec(char *buf, unsigned long long num)
382 {
383 	while (1) {
384 		unsigned rem;
385 		if (num < 100000)
386 			return put_dec_trunc(buf, num);
387 		rem = do_div(num, 100000);
388 		buf = put_dec_full(buf, rem);
389 	}
390 }
391 
392 #define ZEROPAD	1		/* pad with zero */
393 #define SIGN	2		/* unsigned/signed long */
394 #define PLUS	4		/* show plus */
395 #define SPACE	8		/* space if plus */
396 #define LEFT	16		/* left justified */
397 #define SMALL	32		/* Must be 32 == 0x20 */
398 #define SPECIAL	64		/* 0x */
399 
400 enum format_type {
401 	FORMAT_TYPE_NONE, /* Just a string part */
402 	FORMAT_TYPE_WIDTH,
403 	FORMAT_TYPE_PRECISION,
404 	FORMAT_TYPE_CHAR,
405 	FORMAT_TYPE_STR,
406 	FORMAT_TYPE_PTR,
407 	FORMAT_TYPE_PERCENT_CHAR,
408 	FORMAT_TYPE_INVALID,
409 	FORMAT_TYPE_LONG_LONG,
410 	FORMAT_TYPE_ULONG,
411 	FORMAT_TYPE_LONG,
412 	FORMAT_TYPE_UBYTE,
413 	FORMAT_TYPE_BYTE,
414 	FORMAT_TYPE_USHORT,
415 	FORMAT_TYPE_SHORT,
416 	FORMAT_TYPE_UINT,
417 	FORMAT_TYPE_INT,
418 	FORMAT_TYPE_NRCHARS,
419 	FORMAT_TYPE_SIZE_T,
420 	FORMAT_TYPE_PTRDIFF
421 };
422 
423 struct printf_spec {
424 	enum format_type	type;
425 	int			flags;		/* flags to number() */
426 	int			field_width;	/* width of output field */
427 	int			base;
428 	int			precision;	/* # of digits/chars */
429 	int			qualifier;
430 };
431 
432 static char *number(char *buf, char *end, unsigned long long num,
433 			struct printf_spec spec)
434 {
435 	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
436 	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
437 
438 	char tmp[66];
439 	char sign;
440 	char locase;
441 	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
442 	int i;
443 
444 	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
445 	 * produces same digits or (maybe lowercased) letters */
446 	locase = (spec.flags & SMALL);
447 	if (spec.flags & LEFT)
448 		spec.flags &= ~ZEROPAD;
449 	sign = 0;
450 	if (spec.flags & SIGN) {
451 		if ((signed long long) num < 0) {
452 			sign = '-';
453 			num = - (signed long long) num;
454 			spec.field_width--;
455 		} else if (spec.flags & PLUS) {
456 			sign = '+';
457 			spec.field_width--;
458 		} else if (spec.flags & SPACE) {
459 			sign = ' ';
460 			spec.field_width--;
461 		}
462 	}
463 	if (need_pfx) {
464 		spec.field_width--;
465 		if (spec.base == 16)
466 			spec.field_width--;
467 	}
468 
469 	/* generate full string in tmp[], in reverse order */
470 	i = 0;
471 	if (num == 0)
472 		tmp[i++] = '0';
473 	/* Generic code, for any base:
474 	else do {
475 		tmp[i++] = (digits[do_div(num,base)] | locase);
476 	} while (num != 0);
477 	*/
478 	else if (spec.base != 10) { /* 8 or 16 */
479 		int mask = spec.base - 1;
480 		int shift = 3;
481 		if (spec.base == 16) shift = 4;
482 		do {
483 			tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
484 			num >>= shift;
485 		} while (num);
486 	} else { /* base 10 */
487 		i = put_dec(tmp, num) - tmp;
488 	}
489 
490 	/* printing 100 using %2d gives "100", not "00" */
491 	if (i > spec.precision)
492 		spec.precision = i;
493 	/* leading space padding */
494 	spec.field_width -= spec.precision;
495 	if (!(spec.flags & (ZEROPAD+LEFT))) {
496 		while(--spec.field_width >= 0) {
497 			if (buf < end)
498 				*buf = ' ';
499 			++buf;
500 		}
501 	}
502 	/* sign */
503 	if (sign) {
504 		if (buf < end)
505 			*buf = sign;
506 		++buf;
507 	}
508 	/* "0x" / "0" prefix */
509 	if (need_pfx) {
510 		if (buf < end)
511 			*buf = '0';
512 		++buf;
513 		if (spec.base == 16) {
514 			if (buf < end)
515 				*buf = ('X' | locase);
516 			++buf;
517 		}
518 	}
519 	/* zero or space padding */
520 	if (!(spec.flags & LEFT)) {
521 		char c = (spec.flags & ZEROPAD) ? '0' : ' ';
522 		while (--spec.field_width >= 0) {
523 			if (buf < end)
524 				*buf = c;
525 			++buf;
526 		}
527 	}
528 	/* hmm even more zero padding? */
529 	while (i <= --spec.precision) {
530 		if (buf < end)
531 			*buf = '0';
532 		++buf;
533 	}
534 	/* actual digits of result */
535 	while (--i >= 0) {
536 		if (buf < end)
537 			*buf = tmp[i];
538 		++buf;
539 	}
540 	/* trailing space padding */
541 	while (--spec.field_width >= 0) {
542 		if (buf < end)
543 			*buf = ' ';
544 		++buf;
545 	}
546 	return buf;
547 }
548 
549 static char *string(char *buf, char *end, char *s, struct printf_spec spec)
550 {
551 	int len, i;
552 
553 	if ((unsigned long)s < PAGE_SIZE)
554 		s = "<NULL>";
555 
556 	len = strnlen(s, spec.precision);
557 
558 	if (!(spec.flags & LEFT)) {
559 		while (len < spec.field_width--) {
560 			if (buf < end)
561 				*buf = ' ';
562 			++buf;
563 		}
564 	}
565 	for (i = 0; i < len; ++i) {
566 		if (buf < end)
567 			*buf = *s;
568 		++buf; ++s;
569 	}
570 	while (len < spec.field_width--) {
571 		if (buf < end)
572 			*buf = ' ';
573 		++buf;
574 	}
575 	return buf;
576 }
577 
578 static char *symbol_string(char *buf, char *end, void *ptr,
579 				struct printf_spec spec, char ext)
580 {
581 	unsigned long value = (unsigned long) ptr;
582 #ifdef CONFIG_KALLSYMS
583 	char sym[KSYM_SYMBOL_LEN];
584 	if (ext != 'f' && ext != 's')
585 		sprint_symbol(sym, value);
586 	else
587 		kallsyms_lookup(value, NULL, NULL, NULL, sym);
588 	return string(buf, end, sym, spec);
589 #else
590 	spec.field_width = 2*sizeof(void *);
591 	spec.flags |= SPECIAL | SMALL | ZEROPAD;
592 	spec.base = 16;
593 	return number(buf, end, value, spec);
594 #endif
595 }
596 
597 static char *resource_string(char *buf, char *end, struct resource *res,
598 				struct printf_spec spec)
599 {
600 #ifndef IO_RSRC_PRINTK_SIZE
601 #define IO_RSRC_PRINTK_SIZE	4
602 #endif
603 
604 #ifndef MEM_RSRC_PRINTK_SIZE
605 #define MEM_RSRC_PRINTK_SIZE	8
606 #endif
607 	struct printf_spec num_spec = {
608 		.base = 16,
609 		.precision = -1,
610 		.flags = SPECIAL | SMALL | ZEROPAD,
611 	};
612 	/* room for the actual numbers, the two "0x", -, [, ] and the final zero */
613 	char sym[4*sizeof(resource_size_t) + 8];
614 	char *p = sym, *pend = sym + sizeof(sym);
615 	int size = -1;
616 
617 	if (res->flags & IORESOURCE_IO)
618 		size = IO_RSRC_PRINTK_SIZE;
619 	else if (res->flags & IORESOURCE_MEM)
620 		size = MEM_RSRC_PRINTK_SIZE;
621 
622 	*p++ = '[';
623 	num_spec.field_width = size;
624 	p = number(p, pend, res->start, num_spec);
625 	*p++ = '-';
626 	p = number(p, pend, res->end, num_spec);
627 	*p++ = ']';
628 	*p = 0;
629 
630 	return string(buf, end, sym, spec);
631 }
632 
633 static char *mac_address_string(char *buf, char *end, u8 *addr,
634 				struct printf_spec spec, const char *fmt)
635 {
636 	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
637 	char *p = mac_addr;
638 	int i;
639 
640 	for (i = 0; i < 6; i++) {
641 		p = pack_hex_byte(p, addr[i]);
642 		if (fmt[0] == 'M' && i != 5)
643 			*p++ = ':';
644 	}
645 	*p = '\0';
646 
647 	return string(buf, end, mac_addr, spec);
648 }
649 
650 static char *ip4_string(char *p, const u8 *addr, bool leading_zeros)
651 {
652 	int i;
653 
654 	for (i = 0; i < 4; i++) {
655 		char temp[3];	/* hold each IP quad in reverse order */
656 		int digits = put_dec_trunc(temp, addr[i]) - temp;
657 		if (leading_zeros) {
658 			if (digits < 3)
659 				*p++ = '0';
660 			if (digits < 2)
661 				*p++ = '0';
662 		}
663 		/* reverse the digits in the quad */
664 		while (digits--)
665 			*p++ = temp[digits];
666 		if (i < 3)
667 			*p++ = '.';
668 	}
669 
670 	*p = '\0';
671 	return p;
672 }
673 
674 static char *ip6_compressed_string(char *p, const char *addr)
675 {
676 	int i;
677 	int j;
678 	int range;
679 	unsigned char zerolength[8];
680 	int longest = 1;
681 	int colonpos = -1;
682 	u16 word;
683 	u8 hi;
684 	u8 lo;
685 	bool needcolon = false;
686 	bool useIPv4;
687 	struct in6_addr in6;
688 
689 	memcpy(&in6, addr, sizeof(struct in6_addr));
690 
691 	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
692 
693 	memset(zerolength, 0, sizeof(zerolength));
694 
695 	if (useIPv4)
696 		range = 6;
697 	else
698 		range = 8;
699 
700 	/* find position of longest 0 run */
701 	for (i = 0; i < range; i++) {
702 		for (j = i; j < range; j++) {
703 			if (in6.s6_addr16[j] != 0)
704 				break;
705 			zerolength[i]++;
706 		}
707 	}
708 	for (i = 0; i < range; i++) {
709 		if (zerolength[i] > longest) {
710 			longest = zerolength[i];
711 			colonpos = i;
712 		}
713 	}
714 
715 	/* emit address */
716 	for (i = 0; i < range; i++) {
717 		if (i == colonpos) {
718 			if (needcolon || i == 0)
719 				*p++ = ':';
720 			*p++ = ':';
721 			needcolon = false;
722 			i += longest - 1;
723 			continue;
724 		}
725 		if (needcolon) {
726 			*p++ = ':';
727 			needcolon = false;
728 		}
729 		/* hex u16 without leading 0s */
730 		word = ntohs(in6.s6_addr16[i]);
731 		hi = word >> 8;
732 		lo = word & 0xff;
733 		if (hi) {
734 			if (hi > 0x0f)
735 				p = pack_hex_byte(p, hi);
736 			else
737 				*p++ = hex_asc_lo(hi);
738 		}
739 		if (hi || lo > 0x0f)
740 			p = pack_hex_byte(p, lo);
741 		else
742 			*p++ = hex_asc_lo(lo);
743 		needcolon = true;
744 	}
745 
746 	if (useIPv4) {
747 		if (needcolon)
748 			*p++ = ':';
749 		p = ip4_string(p, &in6.s6_addr[12], false);
750 	}
751 
752 	*p = '\0';
753 	return p;
754 }
755 
756 static char *ip6_string(char *p, const char *addr, const char *fmt)
757 {
758 	int i;
759 	for (i = 0; i < 8; i++) {
760 		p = pack_hex_byte(p, *addr++);
761 		p = pack_hex_byte(p, *addr++);
762 		if (fmt[0] == 'I' && i != 7)
763 			*p++ = ':';
764 	}
765 
766 	*p = '\0';
767 	return p;
768 }
769 
770 static char *ip6_addr_string(char *buf, char *end, const u8 *addr,
771 			     struct printf_spec spec, const char *fmt)
772 {
773 	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
774 
775 	if (fmt[0] == 'I' && fmt[2] == 'c')
776 		ip6_compressed_string(ip6_addr, addr);
777 	else
778 		ip6_string(ip6_addr, addr, fmt);
779 
780 	return string(buf, end, ip6_addr, spec);
781 }
782 
783 static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
784 			     struct printf_spec spec, const char *fmt)
785 {
786 	char ip4_addr[sizeof("255.255.255.255")];
787 
788 	ip4_string(ip4_addr, addr, fmt[0] == 'i');
789 
790 	return string(buf, end, ip4_addr, spec);
791 }
792 
793 /*
794  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
795  * by an extra set of alphanumeric characters that are extended format
796  * specifiers.
797  *
798  * Right now we handle:
799  *
800  * - 'F' For symbolic function descriptor pointers with offset
801  * - 'f' For simple symbolic function names without offset
802  * - 'S' For symbolic direct pointers with offset
803  * - 's' For symbolic direct pointers without offset
804  * - 'R' For a struct resource pointer, it prints the range of
805  *       addresses (not the name nor the flags)
806  * - 'M' For a 6-byte MAC address, it prints the address in the
807  *       usual colon-separated hex notation
808  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
809  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
810  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
811  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
812  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
813  *       IPv6 omits the colons (01020304...0f)
814  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
815  * - 'I6c' for IPv6 addresses printed as specified by
816  *       http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt
817  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
818  * function pointers are really function descriptors, which contain a
819  * pointer to the real address.
820  */
821 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
822 			struct printf_spec spec)
823 {
824 	if (!ptr)
825 		return string(buf, end, "(null)", spec);
826 
827 	switch (*fmt) {
828 	case 'F':
829 	case 'f':
830 		ptr = dereference_function_descriptor(ptr);
831 	case 's':
832 		/* Fallthrough */
833 	case 'S':
834 		return symbol_string(buf, end, ptr, spec, *fmt);
835 	case 'R':
836 		return resource_string(buf, end, ptr, spec);
837 	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
838 	case 'm':			/* Contiguous: 000102030405 */
839 		return mac_address_string(buf, end, ptr, spec, fmt);
840 	case 'I':			/* Formatted IP supported
841 					 * 4:	1.2.3.4
842 					 * 6:	0001:0203:...:0708
843 					 * 6c:	1::708 or 1::1.2.3.4
844 					 */
845 	case 'i':			/* Contiguous:
846 					 * 4:	001.002.003.004
847 					 * 6:   000102...0f
848 					 */
849 		switch (fmt[1]) {
850 		case '6':
851 			return ip6_addr_string(buf, end, ptr, spec, fmt);
852 		case '4':
853 			return ip4_addr_string(buf, end, ptr, spec, fmt);
854 		}
855 		break;
856 	}
857 	spec.flags |= SMALL;
858 	if (spec.field_width == -1) {
859 		spec.field_width = 2*sizeof(void *);
860 		spec.flags |= ZEROPAD;
861 	}
862 	spec.base = 16;
863 
864 	return number(buf, end, (unsigned long) ptr, spec);
865 }
866 
867 /*
868  * Helper function to decode printf style format.
869  * Each call decode a token from the format and return the
870  * number of characters read (or likely the delta where it wants
871  * to go on the next call).
872  * The decoded token is returned through the parameters
873  *
874  * 'h', 'l', or 'L' for integer fields
875  * 'z' support added 23/7/1999 S.H.
876  * 'z' changed to 'Z' --davidm 1/25/99
877  * 't' added for ptrdiff_t
878  *
879  * @fmt: the format string
880  * @type of the token returned
881  * @flags: various flags such as +, -, # tokens..
882  * @field_width: overwritten width
883  * @base: base of the number (octal, hex, ...)
884  * @precision: precision of a number
885  * @qualifier: qualifier of a number (long, size_t, ...)
886  */
887 static int format_decode(const char *fmt, struct printf_spec *spec)
888 {
889 	const char *start = fmt;
890 
891 	/* we finished early by reading the field width */
892 	if (spec->type == FORMAT_TYPE_WIDTH) {
893 		if (spec->field_width < 0) {
894 			spec->field_width = -spec->field_width;
895 			spec->flags |= LEFT;
896 		}
897 		spec->type = FORMAT_TYPE_NONE;
898 		goto precision;
899 	}
900 
901 	/* we finished early by reading the precision */
902 	if (spec->type == FORMAT_TYPE_PRECISION) {
903 		if (spec->precision < 0)
904 			spec->precision = 0;
905 
906 		spec->type = FORMAT_TYPE_NONE;
907 		goto qualifier;
908 	}
909 
910 	/* By default */
911 	spec->type = FORMAT_TYPE_NONE;
912 
913 	for (; *fmt ; ++fmt) {
914 		if (*fmt == '%')
915 			break;
916 	}
917 
918 	/* Return the current non-format string */
919 	if (fmt != start || !*fmt)
920 		return fmt - start;
921 
922 	/* Process flags */
923 	spec->flags = 0;
924 
925 	while (1) { /* this also skips first '%' */
926 		bool found = true;
927 
928 		++fmt;
929 
930 		switch (*fmt) {
931 		case '-': spec->flags |= LEFT;    break;
932 		case '+': spec->flags |= PLUS;    break;
933 		case ' ': spec->flags |= SPACE;   break;
934 		case '#': spec->flags |= SPECIAL; break;
935 		case '0': spec->flags |= ZEROPAD; break;
936 		default:  found = false;
937 		}
938 
939 		if (!found)
940 			break;
941 	}
942 
943 	/* get field width */
944 	spec->field_width = -1;
945 
946 	if (isdigit(*fmt))
947 		spec->field_width = skip_atoi(&fmt);
948 	else if (*fmt == '*') {
949 		/* it's the next argument */
950 		spec->type = FORMAT_TYPE_WIDTH;
951 		return ++fmt - start;
952 	}
953 
954 precision:
955 	/* get the precision */
956 	spec->precision = -1;
957 	if (*fmt == '.') {
958 		++fmt;
959 		if (isdigit(*fmt)) {
960 			spec->precision = skip_atoi(&fmt);
961 			if (spec->precision < 0)
962 				spec->precision = 0;
963 		} else if (*fmt == '*') {
964 			/* it's the next argument */
965 			spec->type = FORMAT_TYPE_PRECISION;
966 			return ++fmt - start;
967 		}
968 	}
969 
970 qualifier:
971 	/* get the conversion qualifier */
972 	spec->qualifier = -1;
973 	if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
974 	    *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
975 		spec->qualifier = *fmt++;
976 		if (unlikely(spec->qualifier == *fmt)) {
977 			if (spec->qualifier == 'l') {
978 				spec->qualifier = 'L';
979 				++fmt;
980 			} else if (spec->qualifier == 'h') {
981 				spec->qualifier = 'H';
982 				++fmt;
983 			}
984 		}
985 	}
986 
987 	/* default base */
988 	spec->base = 10;
989 	switch (*fmt) {
990 	case 'c':
991 		spec->type = FORMAT_TYPE_CHAR;
992 		return ++fmt - start;
993 
994 	case 's':
995 		spec->type = FORMAT_TYPE_STR;
996 		return ++fmt - start;
997 
998 	case 'p':
999 		spec->type = FORMAT_TYPE_PTR;
1000 		return fmt - start;
1001 		/* skip alnum */
1002 
1003 	case 'n':
1004 		spec->type = FORMAT_TYPE_NRCHARS;
1005 		return ++fmt - start;
1006 
1007 	case '%':
1008 		spec->type = FORMAT_TYPE_PERCENT_CHAR;
1009 		return ++fmt - start;
1010 
1011 	/* integer number formats - set up the flags and "break" */
1012 	case 'o':
1013 		spec->base = 8;
1014 		break;
1015 
1016 	case 'x':
1017 		spec->flags |= SMALL;
1018 
1019 	case 'X':
1020 		spec->base = 16;
1021 		break;
1022 
1023 	case 'd':
1024 	case 'i':
1025 		spec->flags |= SIGN;
1026 	case 'u':
1027 		break;
1028 
1029 	default:
1030 		spec->type = FORMAT_TYPE_INVALID;
1031 		return fmt - start;
1032 	}
1033 
1034 	if (spec->qualifier == 'L')
1035 		spec->type = FORMAT_TYPE_LONG_LONG;
1036 	else if (spec->qualifier == 'l') {
1037 		if (spec->flags & SIGN)
1038 			spec->type = FORMAT_TYPE_LONG;
1039 		else
1040 			spec->type = FORMAT_TYPE_ULONG;
1041 	} else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
1042 		spec->type = FORMAT_TYPE_SIZE_T;
1043 	} else if (spec->qualifier == 't') {
1044 		spec->type = FORMAT_TYPE_PTRDIFF;
1045 	} else if (spec->qualifier == 'H') {
1046 		if (spec->flags & SIGN)
1047 			spec->type = FORMAT_TYPE_BYTE;
1048 		else
1049 			spec->type = FORMAT_TYPE_UBYTE;
1050 	} else if (spec->qualifier == 'h') {
1051 		if (spec->flags & SIGN)
1052 			spec->type = FORMAT_TYPE_SHORT;
1053 		else
1054 			spec->type = FORMAT_TYPE_USHORT;
1055 	} else {
1056 		if (spec->flags & SIGN)
1057 			spec->type = FORMAT_TYPE_INT;
1058 		else
1059 			spec->type = FORMAT_TYPE_UINT;
1060 	}
1061 
1062 	return ++fmt - start;
1063 }
1064 
1065 /**
1066  * vsnprintf - Format a string and place it in a buffer
1067  * @buf: The buffer to place the result into
1068  * @size: The size of the buffer, including the trailing null space
1069  * @fmt: The format string to use
1070  * @args: Arguments for the format string
1071  *
1072  * This function follows C99 vsnprintf, but has some extensions:
1073  * %pS output the name of a text symbol with offset
1074  * %ps output the name of a text symbol without offset
1075  * %pF output the name of a function pointer with its offset
1076  * %pf output the name of a function pointer without its offset
1077  * %pR output the address range in a struct resource
1078  * %n is ignored
1079  *
1080  * The return value is the number of characters which would
1081  * be generated for the given input, excluding the trailing
1082  * '\0', as per ISO C99. If you want to have the exact
1083  * number of characters written into @buf as return value
1084  * (not including the trailing '\0'), use vscnprintf(). If the
1085  * return is greater than or equal to @size, the resulting
1086  * string is truncated.
1087  *
1088  * Call this function if you are already dealing with a va_list.
1089  * You probably want snprintf() instead.
1090  */
1091 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1092 {
1093 	unsigned long long num;
1094 	char *str, *end, c;
1095 	int read;
1096 	struct printf_spec spec = {0};
1097 
1098 	/* Reject out-of-range values early.  Large positive sizes are
1099 	   used for unknown buffer sizes. */
1100 	if (WARN_ON_ONCE((int) size < 0))
1101 		return 0;
1102 
1103 	str = buf;
1104 	end = buf + size;
1105 
1106 	/* Make sure end is always >= buf */
1107 	if (end < buf) {
1108 		end = ((void *)-1);
1109 		size = end - buf;
1110 	}
1111 
1112 	while (*fmt) {
1113 		const char *old_fmt = fmt;
1114 
1115 		read = format_decode(fmt, &spec);
1116 
1117 		fmt += read;
1118 
1119 		switch (spec.type) {
1120 		case FORMAT_TYPE_NONE: {
1121 			int copy = read;
1122 			if (str < end) {
1123 				if (copy > end - str)
1124 					copy = end - str;
1125 				memcpy(str, old_fmt, copy);
1126 			}
1127 			str += read;
1128 			break;
1129 		}
1130 
1131 		case FORMAT_TYPE_WIDTH:
1132 			spec.field_width = va_arg(args, int);
1133 			break;
1134 
1135 		case FORMAT_TYPE_PRECISION:
1136 			spec.precision = va_arg(args, int);
1137 			break;
1138 
1139 		case FORMAT_TYPE_CHAR:
1140 			if (!(spec.flags & LEFT)) {
1141 				while (--spec.field_width > 0) {
1142 					if (str < end)
1143 						*str = ' ';
1144 					++str;
1145 
1146 				}
1147 			}
1148 			c = (unsigned char) va_arg(args, int);
1149 			if (str < end)
1150 				*str = c;
1151 			++str;
1152 			while (--spec.field_width > 0) {
1153 				if (str < end)
1154 					*str = ' ';
1155 				++str;
1156 			}
1157 			break;
1158 
1159 		case FORMAT_TYPE_STR:
1160 			str = string(str, end, va_arg(args, char *), spec);
1161 			break;
1162 
1163 		case FORMAT_TYPE_PTR:
1164 			str = pointer(fmt+1, str, end, va_arg(args, void *),
1165 				      spec);
1166 			while (isalnum(*fmt))
1167 				fmt++;
1168 			break;
1169 
1170 		case FORMAT_TYPE_PERCENT_CHAR:
1171 			if (str < end)
1172 				*str = '%';
1173 			++str;
1174 			break;
1175 
1176 		case FORMAT_TYPE_INVALID:
1177 			if (str < end)
1178 				*str = '%';
1179 			++str;
1180 			break;
1181 
1182 		case FORMAT_TYPE_NRCHARS: {
1183 			int qualifier = spec.qualifier;
1184 
1185 			if (qualifier == 'l') {
1186 				long *ip = va_arg(args, long *);
1187 				*ip = (str - buf);
1188 			} else if (qualifier == 'Z' ||
1189 					qualifier == 'z') {
1190 				size_t *ip = va_arg(args, size_t *);
1191 				*ip = (str - buf);
1192 			} else {
1193 				int *ip = va_arg(args, int *);
1194 				*ip = (str - buf);
1195 			}
1196 			break;
1197 		}
1198 
1199 		default:
1200 			switch (spec.type) {
1201 			case FORMAT_TYPE_LONG_LONG:
1202 				num = va_arg(args, long long);
1203 				break;
1204 			case FORMAT_TYPE_ULONG:
1205 				num = va_arg(args, unsigned long);
1206 				break;
1207 			case FORMAT_TYPE_LONG:
1208 				num = va_arg(args, long);
1209 				break;
1210 			case FORMAT_TYPE_SIZE_T:
1211 				num = va_arg(args, size_t);
1212 				break;
1213 			case FORMAT_TYPE_PTRDIFF:
1214 				num = va_arg(args, ptrdiff_t);
1215 				break;
1216 			case FORMAT_TYPE_UBYTE:
1217 				num = (unsigned char) va_arg(args, int);
1218 				break;
1219 			case FORMAT_TYPE_BYTE:
1220 				num = (signed char) va_arg(args, int);
1221 				break;
1222 			case FORMAT_TYPE_USHORT:
1223 				num = (unsigned short) va_arg(args, int);
1224 				break;
1225 			case FORMAT_TYPE_SHORT:
1226 				num = (short) va_arg(args, int);
1227 				break;
1228 			case FORMAT_TYPE_INT:
1229 				num = (int) va_arg(args, int);
1230 				break;
1231 			default:
1232 				num = va_arg(args, unsigned int);
1233 			}
1234 
1235 			str = number(str, end, num, spec);
1236 		}
1237 	}
1238 
1239 	if (size > 0) {
1240 		if (str < end)
1241 			*str = '\0';
1242 		else
1243 			end[-1] = '\0';
1244 	}
1245 
1246 	/* the trailing null byte doesn't count towards the total */
1247 	return str-buf;
1248 
1249 }
1250 EXPORT_SYMBOL(vsnprintf);
1251 
1252 /**
1253  * vscnprintf - Format a string and place it in a buffer
1254  * @buf: The buffer to place the result into
1255  * @size: The size of the buffer, including the trailing null space
1256  * @fmt: The format string to use
1257  * @args: Arguments for the format string
1258  *
1259  * The return value is the number of characters which have been written into
1260  * the @buf not including the trailing '\0'. If @size is <= 0 the function
1261  * returns 0.
1262  *
1263  * Call this function if you are already dealing with a va_list.
1264  * You probably want scnprintf() instead.
1265  *
1266  * See the vsnprintf() documentation for format string extensions over C99.
1267  */
1268 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1269 {
1270 	int i;
1271 
1272 	i=vsnprintf(buf,size,fmt,args);
1273 	return (i >= size) ? (size - 1) : i;
1274 }
1275 EXPORT_SYMBOL(vscnprintf);
1276 
1277 /**
1278  * snprintf - Format a string and place it in a buffer
1279  * @buf: The buffer to place the result into
1280  * @size: The size of the buffer, including the trailing null space
1281  * @fmt: The format string to use
1282  * @...: Arguments for the format string
1283  *
1284  * The return value is the number of characters which would be
1285  * generated for the given input, excluding the trailing null,
1286  * as per ISO C99.  If the return is greater than or equal to
1287  * @size, the resulting string is truncated.
1288  *
1289  * See the vsnprintf() documentation for format string extensions over C99.
1290  */
1291 int snprintf(char * buf, size_t size, const char *fmt, ...)
1292 {
1293 	va_list args;
1294 	int i;
1295 
1296 	va_start(args, fmt);
1297 	i=vsnprintf(buf,size,fmt,args);
1298 	va_end(args);
1299 	return i;
1300 }
1301 EXPORT_SYMBOL(snprintf);
1302 
1303 /**
1304  * scnprintf - Format a string and place it in a buffer
1305  * @buf: The buffer to place the result into
1306  * @size: The size of the buffer, including the trailing null space
1307  * @fmt: The format string to use
1308  * @...: Arguments for the format string
1309  *
1310  * The return value is the number of characters written into @buf not including
1311  * the trailing '\0'. If @size is <= 0 the function returns 0.
1312  */
1313 
1314 int scnprintf(char * buf, size_t size, const char *fmt, ...)
1315 {
1316 	va_list args;
1317 	int i;
1318 
1319 	va_start(args, fmt);
1320 	i = vsnprintf(buf, size, fmt, args);
1321 	va_end(args);
1322 	return (i >= size) ? (size - 1) : i;
1323 }
1324 EXPORT_SYMBOL(scnprintf);
1325 
1326 /**
1327  * vsprintf - Format a string and place it in a buffer
1328  * @buf: The buffer to place the result into
1329  * @fmt: The format string to use
1330  * @args: Arguments for the format string
1331  *
1332  * The function returns the number of characters written
1333  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1334  * buffer overflows.
1335  *
1336  * Call this function if you are already dealing with a va_list.
1337  * You probably want sprintf() instead.
1338  *
1339  * See the vsnprintf() documentation for format string extensions over C99.
1340  */
1341 int vsprintf(char *buf, const char *fmt, va_list args)
1342 {
1343 	return vsnprintf(buf, INT_MAX, fmt, args);
1344 }
1345 EXPORT_SYMBOL(vsprintf);
1346 
1347 /**
1348  * sprintf - Format a string and place it in a buffer
1349  * @buf: The buffer to place the result into
1350  * @fmt: The format string to use
1351  * @...: Arguments for the format string
1352  *
1353  * The function returns the number of characters written
1354  * into @buf. Use snprintf() or scnprintf() in order to avoid
1355  * buffer overflows.
1356  *
1357  * See the vsnprintf() documentation for format string extensions over C99.
1358  */
1359 int sprintf(char * buf, const char *fmt, ...)
1360 {
1361 	va_list args;
1362 	int i;
1363 
1364 	va_start(args, fmt);
1365 	i=vsnprintf(buf, INT_MAX, fmt, args);
1366 	va_end(args);
1367 	return i;
1368 }
1369 EXPORT_SYMBOL(sprintf);
1370 
1371 #ifdef CONFIG_BINARY_PRINTF
1372 /*
1373  * bprintf service:
1374  * vbin_printf() - VA arguments to binary data
1375  * bstr_printf() - Binary data to text string
1376  */
1377 
1378 /**
1379  * vbin_printf - Parse a format string and place args' binary value in a buffer
1380  * @bin_buf: The buffer to place args' binary value
1381  * @size: The size of the buffer(by words(32bits), not characters)
1382  * @fmt: The format string to use
1383  * @args: Arguments for the format string
1384  *
1385  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1386  * is skiped.
1387  *
1388  * The return value is the number of words(32bits) which would be generated for
1389  * the given input.
1390  *
1391  * NOTE:
1392  * If the return value is greater than @size, the resulting bin_buf is NOT
1393  * valid for bstr_printf().
1394  */
1395 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1396 {
1397 	struct printf_spec spec = {0};
1398 	char *str, *end;
1399 	int read;
1400 
1401 	str = (char *)bin_buf;
1402 	end = (char *)(bin_buf + size);
1403 
1404 #define save_arg(type)							\
1405 do {									\
1406 	if (sizeof(type) == 8) {					\
1407 		unsigned long long value;				\
1408 		str = PTR_ALIGN(str, sizeof(u32));			\
1409 		value = va_arg(args, unsigned long long);		\
1410 		if (str + sizeof(type) <= end) {			\
1411 			*(u32 *)str = *(u32 *)&value;			\
1412 			*(u32 *)(str + 4) = *((u32 *)&value + 1);	\
1413 		}							\
1414 	} else {							\
1415 		unsigned long value;					\
1416 		str = PTR_ALIGN(str, sizeof(type));			\
1417 		value = va_arg(args, int);				\
1418 		if (str + sizeof(type) <= end)				\
1419 			*(typeof(type) *)str = (type)value;		\
1420 	}								\
1421 	str += sizeof(type);						\
1422 } while (0)
1423 
1424 
1425 	while (*fmt) {
1426 		read = format_decode(fmt, &spec);
1427 
1428 		fmt += read;
1429 
1430 		switch (spec.type) {
1431 		case FORMAT_TYPE_NONE:
1432 			break;
1433 
1434 		case FORMAT_TYPE_WIDTH:
1435 		case FORMAT_TYPE_PRECISION:
1436 			save_arg(int);
1437 			break;
1438 
1439 		case FORMAT_TYPE_CHAR:
1440 			save_arg(char);
1441 			break;
1442 
1443 		case FORMAT_TYPE_STR: {
1444 			const char *save_str = va_arg(args, char *);
1445 			size_t len;
1446 			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1447 					|| (unsigned long)save_str < PAGE_SIZE)
1448 				save_str = "<NULL>";
1449 			len = strlen(save_str);
1450 			if (str + len + 1 < end)
1451 				memcpy(str, save_str, len + 1);
1452 			str += len + 1;
1453 			break;
1454 		}
1455 
1456 		case FORMAT_TYPE_PTR:
1457 			save_arg(void *);
1458 			/* skip all alphanumeric pointer suffixes */
1459 			while (isalnum(*fmt))
1460 				fmt++;
1461 			break;
1462 
1463 		case FORMAT_TYPE_PERCENT_CHAR:
1464 			break;
1465 
1466 		case FORMAT_TYPE_INVALID:
1467 			break;
1468 
1469 		case FORMAT_TYPE_NRCHARS: {
1470 			/* skip %n 's argument */
1471 			int qualifier = spec.qualifier;
1472 			void *skip_arg;
1473 			if (qualifier == 'l')
1474 				skip_arg = va_arg(args, long *);
1475 			else if (qualifier == 'Z' || qualifier == 'z')
1476 				skip_arg = va_arg(args, size_t *);
1477 			else
1478 				skip_arg = va_arg(args, int *);
1479 			break;
1480 		}
1481 
1482 		default:
1483 			switch (spec.type) {
1484 
1485 			case FORMAT_TYPE_LONG_LONG:
1486 				save_arg(long long);
1487 				break;
1488 			case FORMAT_TYPE_ULONG:
1489 			case FORMAT_TYPE_LONG:
1490 				save_arg(unsigned long);
1491 				break;
1492 			case FORMAT_TYPE_SIZE_T:
1493 				save_arg(size_t);
1494 				break;
1495 			case FORMAT_TYPE_PTRDIFF:
1496 				save_arg(ptrdiff_t);
1497 				break;
1498 			case FORMAT_TYPE_UBYTE:
1499 			case FORMAT_TYPE_BYTE:
1500 				save_arg(char);
1501 				break;
1502 			case FORMAT_TYPE_USHORT:
1503 			case FORMAT_TYPE_SHORT:
1504 				save_arg(short);
1505 				break;
1506 			default:
1507 				save_arg(int);
1508 			}
1509 		}
1510 	}
1511 	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1512 
1513 #undef save_arg
1514 }
1515 EXPORT_SYMBOL_GPL(vbin_printf);
1516 
1517 /**
1518  * bstr_printf - Format a string from binary arguments and place it in a buffer
1519  * @buf: The buffer to place the result into
1520  * @size: The size of the buffer, including the trailing null space
1521  * @fmt: The format string to use
1522  * @bin_buf: Binary arguments for the format string
1523  *
1524  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1525  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1526  * a binary buffer that generated by vbin_printf.
1527  *
1528  * The format follows C99 vsnprintf, but has some extensions:
1529  *  see vsnprintf comment for details.
1530  *
1531  * The return value is the number of characters which would
1532  * be generated for the given input, excluding the trailing
1533  * '\0', as per ISO C99. If you want to have the exact
1534  * number of characters written into @buf as return value
1535  * (not including the trailing '\0'), use vscnprintf(). If the
1536  * return is greater than or equal to @size, the resulting
1537  * string is truncated.
1538  */
1539 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1540 {
1541 	unsigned long long num;
1542 	char *str, *end, c;
1543 	const char *args = (const char *)bin_buf;
1544 
1545 	struct printf_spec spec = {0};
1546 
1547 	if (WARN_ON_ONCE((int) size < 0))
1548 		return 0;
1549 
1550 	str = buf;
1551 	end = buf + size;
1552 
1553 #define get_arg(type)							\
1554 ({									\
1555 	typeof(type) value;						\
1556 	if (sizeof(type) == 8) {					\
1557 		args = PTR_ALIGN(args, sizeof(u32));			\
1558 		*(u32 *)&value = *(u32 *)args;				\
1559 		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
1560 	} else {							\
1561 		args = PTR_ALIGN(args, sizeof(type));			\
1562 		value = *(typeof(type) *)args;				\
1563 	}								\
1564 	args += sizeof(type);						\
1565 	value;								\
1566 })
1567 
1568 	/* Make sure end is always >= buf */
1569 	if (end < buf) {
1570 		end = ((void *)-1);
1571 		size = end - buf;
1572 	}
1573 
1574 	while (*fmt) {
1575 		int read;
1576 		const char *old_fmt = fmt;
1577 
1578 		read = format_decode(fmt, &spec);
1579 
1580 		fmt += read;
1581 
1582 		switch (spec.type) {
1583 		case FORMAT_TYPE_NONE: {
1584 			int copy = read;
1585 			if (str < end) {
1586 				if (copy > end - str)
1587 					copy = end - str;
1588 				memcpy(str, old_fmt, copy);
1589 			}
1590 			str += read;
1591 			break;
1592 		}
1593 
1594 		case FORMAT_TYPE_WIDTH:
1595 			spec.field_width = get_arg(int);
1596 			break;
1597 
1598 		case FORMAT_TYPE_PRECISION:
1599 			spec.precision = get_arg(int);
1600 			break;
1601 
1602 		case FORMAT_TYPE_CHAR:
1603 			if (!(spec.flags & LEFT)) {
1604 				while (--spec.field_width > 0) {
1605 					if (str < end)
1606 						*str = ' ';
1607 					++str;
1608 				}
1609 			}
1610 			c = (unsigned char) get_arg(char);
1611 			if (str < end)
1612 				*str = c;
1613 			++str;
1614 			while (--spec.field_width > 0) {
1615 				if (str < end)
1616 					*str = ' ';
1617 				++str;
1618 			}
1619 			break;
1620 
1621 		case FORMAT_TYPE_STR: {
1622 			const char *str_arg = args;
1623 			size_t len = strlen(str_arg);
1624 			args += len + 1;
1625 			str = string(str, end, (char *)str_arg, spec);
1626 			break;
1627 		}
1628 
1629 		case FORMAT_TYPE_PTR:
1630 			str = pointer(fmt+1, str, end, get_arg(void *), spec);
1631 			while (isalnum(*fmt))
1632 				fmt++;
1633 			break;
1634 
1635 		case FORMAT_TYPE_PERCENT_CHAR:
1636 			if (str < end)
1637 				*str = '%';
1638 			++str;
1639 			break;
1640 
1641 		case FORMAT_TYPE_INVALID:
1642 			if (str < end)
1643 				*str = '%';
1644 			++str;
1645 			break;
1646 
1647 		case FORMAT_TYPE_NRCHARS:
1648 			/* skip */
1649 			break;
1650 
1651 		default:
1652 			switch (spec.type) {
1653 
1654 			case FORMAT_TYPE_LONG_LONG:
1655 				num = get_arg(long long);
1656 				break;
1657 			case FORMAT_TYPE_ULONG:
1658 				num = get_arg(unsigned long);
1659 				break;
1660 			case FORMAT_TYPE_LONG:
1661 				num = get_arg(unsigned long);
1662 				break;
1663 			case FORMAT_TYPE_SIZE_T:
1664 				num = get_arg(size_t);
1665 				break;
1666 			case FORMAT_TYPE_PTRDIFF:
1667 				num = get_arg(ptrdiff_t);
1668 				break;
1669 			case FORMAT_TYPE_UBYTE:
1670 				num = get_arg(unsigned char);
1671 				break;
1672 			case FORMAT_TYPE_BYTE:
1673 				num = get_arg(signed char);
1674 				break;
1675 			case FORMAT_TYPE_USHORT:
1676 				num = get_arg(unsigned short);
1677 				break;
1678 			case FORMAT_TYPE_SHORT:
1679 				num = get_arg(short);
1680 				break;
1681 			case FORMAT_TYPE_UINT:
1682 				num = get_arg(unsigned int);
1683 				break;
1684 			default:
1685 				num = get_arg(int);
1686 			}
1687 
1688 			str = number(str, end, num, spec);
1689 		}
1690 	}
1691 
1692 	if (size > 0) {
1693 		if (str < end)
1694 			*str = '\0';
1695 		else
1696 			end[-1] = '\0';
1697 	}
1698 
1699 #undef get_arg
1700 
1701 	/* the trailing null byte doesn't count towards the total */
1702 	return str - buf;
1703 }
1704 EXPORT_SYMBOL_GPL(bstr_printf);
1705 
1706 /**
1707  * bprintf - Parse a format string and place args' binary value in a buffer
1708  * @bin_buf: The buffer to place args' binary value
1709  * @size: The size of the buffer(by words(32bits), not characters)
1710  * @fmt: The format string to use
1711  * @...: Arguments for the format string
1712  *
1713  * The function returns the number of words(u32) written
1714  * into @bin_buf.
1715  */
1716 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1717 {
1718 	va_list args;
1719 	int ret;
1720 
1721 	va_start(args, fmt);
1722 	ret = vbin_printf(bin_buf, size, fmt, args);
1723 	va_end(args);
1724 	return ret;
1725 }
1726 EXPORT_SYMBOL_GPL(bprintf);
1727 
1728 #endif /* CONFIG_BINARY_PRINTF */
1729 
1730 /**
1731  * vsscanf - Unformat a buffer into a list of arguments
1732  * @buf:	input buffer
1733  * @fmt:	format of buffer
1734  * @args:	arguments
1735  */
1736 int vsscanf(const char * buf, const char * fmt, va_list args)
1737 {
1738 	const char *str = buf;
1739 	char *next;
1740 	char digit;
1741 	int num = 0;
1742 	int qualifier;
1743 	int base;
1744 	int field_width;
1745 	int is_sign = 0;
1746 
1747 	while(*fmt && *str) {
1748 		/* skip any white space in format */
1749 		/* white space in format matchs any amount of
1750 		 * white space, including none, in the input.
1751 		 */
1752 		if (isspace(*fmt)) {
1753 			while (isspace(*fmt))
1754 				++fmt;
1755 			while (isspace(*str))
1756 				++str;
1757 		}
1758 
1759 		/* anything that is not a conversion must match exactly */
1760 		if (*fmt != '%' && *fmt) {
1761 			if (*fmt++ != *str++)
1762 				break;
1763 			continue;
1764 		}
1765 
1766 		if (!*fmt)
1767 			break;
1768 		++fmt;
1769 
1770 		/* skip this conversion.
1771 		 * advance both strings to next white space
1772 		 */
1773 		if (*fmt == '*') {
1774 			while (!isspace(*fmt) && *fmt != '%' && *fmt)
1775 				fmt++;
1776 			while (!isspace(*str) && *str)
1777 				str++;
1778 			continue;
1779 		}
1780 
1781 		/* get field width */
1782 		field_width = -1;
1783 		if (isdigit(*fmt))
1784 			field_width = skip_atoi(&fmt);
1785 
1786 		/* get conversion qualifier */
1787 		qualifier = -1;
1788 		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
1789 		    *fmt == 'Z' || *fmt == 'z') {
1790 			qualifier = *fmt++;
1791 			if (unlikely(qualifier == *fmt)) {
1792 				if (qualifier == 'h') {
1793 					qualifier = 'H';
1794 					fmt++;
1795 				} else if (qualifier == 'l') {
1796 					qualifier = 'L';
1797 					fmt++;
1798 				}
1799 			}
1800 		}
1801 		base = 10;
1802 		is_sign = 0;
1803 
1804 		if (!*fmt || !*str)
1805 			break;
1806 
1807 		switch(*fmt++) {
1808 		case 'c':
1809 		{
1810 			char *s = (char *) va_arg(args,char*);
1811 			if (field_width == -1)
1812 				field_width = 1;
1813 			do {
1814 				*s++ = *str++;
1815 			} while (--field_width > 0 && *str);
1816 			num++;
1817 		}
1818 		continue;
1819 		case 's':
1820 		{
1821 			char *s = (char *) va_arg(args, char *);
1822 			if(field_width == -1)
1823 				field_width = INT_MAX;
1824 			/* first, skip leading white space in buffer */
1825 			while (isspace(*str))
1826 				str++;
1827 
1828 			/* now copy until next white space */
1829 			while (*str && !isspace(*str) && field_width--) {
1830 				*s++ = *str++;
1831 			}
1832 			*s = '\0';
1833 			num++;
1834 		}
1835 		continue;
1836 		case 'n':
1837 			/* return number of characters read so far */
1838 		{
1839 			int *i = (int *)va_arg(args,int*);
1840 			*i = str - buf;
1841 		}
1842 		continue;
1843 		case 'o':
1844 			base = 8;
1845 			break;
1846 		case 'x':
1847 		case 'X':
1848 			base = 16;
1849 			break;
1850 		case 'i':
1851                         base = 0;
1852 		case 'd':
1853 			is_sign = 1;
1854 		case 'u':
1855 			break;
1856 		case '%':
1857 			/* looking for '%' in str */
1858 			if (*str++ != '%')
1859 				return num;
1860 			continue;
1861 		default:
1862 			/* invalid format; stop here */
1863 			return num;
1864 		}
1865 
1866 		/* have some sort of integer conversion.
1867 		 * first, skip white space in buffer.
1868 		 */
1869 		while (isspace(*str))
1870 			str++;
1871 
1872 		digit = *str;
1873 		if (is_sign && digit == '-')
1874 			digit = *(str + 1);
1875 
1876 		if (!digit
1877                     || (base == 16 && !isxdigit(digit))
1878                     || (base == 10 && !isdigit(digit))
1879                     || (base == 8 && (!isdigit(digit) || digit > '7'))
1880                     || (base == 0 && !isdigit(digit)))
1881 				break;
1882 
1883 		switch(qualifier) {
1884 		case 'H':	/* that's 'hh' in format */
1885 			if (is_sign) {
1886 				signed char *s = (signed char *) va_arg(args,signed char *);
1887 				*s = (signed char) simple_strtol(str,&next,base);
1888 			} else {
1889 				unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
1890 				*s = (unsigned char) simple_strtoul(str, &next, base);
1891 			}
1892 			break;
1893 		case 'h':
1894 			if (is_sign) {
1895 				short *s = (short *) va_arg(args,short *);
1896 				*s = (short) simple_strtol(str,&next,base);
1897 			} else {
1898 				unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
1899 				*s = (unsigned short) simple_strtoul(str, &next, base);
1900 			}
1901 			break;
1902 		case 'l':
1903 			if (is_sign) {
1904 				long *l = (long *) va_arg(args,long *);
1905 				*l = simple_strtol(str,&next,base);
1906 			} else {
1907 				unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
1908 				*l = simple_strtoul(str,&next,base);
1909 			}
1910 			break;
1911 		case 'L':
1912 			if (is_sign) {
1913 				long long *l = (long long*) va_arg(args,long long *);
1914 				*l = simple_strtoll(str,&next,base);
1915 			} else {
1916 				unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
1917 				*l = simple_strtoull(str,&next,base);
1918 			}
1919 			break;
1920 		case 'Z':
1921 		case 'z':
1922 		{
1923 			size_t *s = (size_t*) va_arg(args,size_t*);
1924 			*s = (size_t) simple_strtoul(str,&next,base);
1925 		}
1926 		break;
1927 		default:
1928 			if (is_sign) {
1929 				int *i = (int *) va_arg(args, int*);
1930 				*i = (int) simple_strtol(str,&next,base);
1931 			} else {
1932 				unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
1933 				*i = (unsigned int) simple_strtoul(str,&next,base);
1934 			}
1935 			break;
1936 		}
1937 		num++;
1938 
1939 		if (!next)
1940 			break;
1941 		str = next;
1942 	}
1943 
1944 	/*
1945 	 * Now we've come all the way through so either the input string or the
1946 	 * format ended. In the former case, there can be a %n at the current
1947 	 * position in the format that needs to be filled.
1948 	 */
1949 	if (*fmt == '%' && *(fmt + 1) == 'n') {
1950 		int *p = (int *)va_arg(args, int *);
1951 		*p = str - buf;
1952 	}
1953 
1954 	return num;
1955 }
1956 EXPORT_SYMBOL(vsscanf);
1957 
1958 /**
1959  * sscanf - Unformat a buffer into a list of arguments
1960  * @buf:	input buffer
1961  * @fmt:	formatting of buffer
1962  * @...:	resulting arguments
1963  */
1964 int sscanf(const char * buf, const char * fmt, ...)
1965 {
1966 	va_list args;
1967 	int i;
1968 
1969 	va_start(args,fmt);
1970 	i = vsscanf(buf,fmt,args);
1971 	va_end(args);
1972 	return i;
1973 }
1974 EXPORT_SYMBOL(sscanf);
1975