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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/clk.h>
21#include <linux/clk-provider.h>
22#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
23#include <linux/types.h>
24#include <linux/string.h>
25#include <linux/ctype.h>
26#include <linux/kernel.h>
27#include <linux/kallsyms.h>
28#include <linux/math64.h>
29#include <linux/uaccess.h>
30#include <linux/ioport.h>
31#include <linux/dcache.h>
32#include <linux/cred.h>
33#include <linux/uuid.h>
34#include <net/addrconf.h>
35#ifdef CONFIG_BLOCK
36#include <linux/blkdev.h>
37#endif
38
39#include "../mm/internal.h" /* For the trace_print_flags arrays */
40
41#include <asm/page.h> /* for PAGE_SIZE */
42#include <asm/sections.h> /* for dereference_function_descriptor() */
43#include <asm/byteorder.h> /* cpu_to_le16 */
44
45#include <linux/string_helpers.h>
46#include "kstrtox.h"
47
48/**
49 * simple_strtoull - convert a string to an unsigned long long
50 * @cp: The start of the string
51 * @endp: A pointer to the end of the parsed string will be placed here
52 * @base: The number base to use
53 *
54 * This function is obsolete. Please use kstrtoull instead.
55 */
56unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
57{
58 unsigned long long result;
59 unsigned int rv;
60
61 cp = _parse_integer_fixup_radix(cp, &base);
62 rv = _parse_integer(cp, base, &result);
63 /* FIXME */
64 cp += (rv & ~KSTRTOX_OVERFLOW);
65
66 if (endp)
67 *endp = (char *)cp;
68
69 return result;
70}
71EXPORT_SYMBOL(simple_strtoull);
72
73/**
74 * simple_strtoul - convert a string to an unsigned long
75 * @cp: The start of the string
76 * @endp: A pointer to the end of the parsed string will be placed here
77 * @base: The number base to use
78 *
79 * This function is obsolete. Please use kstrtoul instead.
80 */
81unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
82{
83 return simple_strtoull(cp, endp, base);
84}
85EXPORT_SYMBOL(simple_strtoul);
86
87/**
88 * simple_strtol - convert a string to a signed long
89 * @cp: The start of the string
90 * @endp: A pointer to the end of the parsed string will be placed here
91 * @base: The number base to use
92 *
93 * This function is obsolete. Please use kstrtol instead.
94 */
95long simple_strtol(const char *cp, char **endp, unsigned int base)
96{
97 if (*cp == '-')
98 return -simple_strtoul(cp + 1, endp, base);
99
100 return simple_strtoul(cp, endp, base);
101}
102EXPORT_SYMBOL(simple_strtol);
103
104/**
105 * simple_strtoll - convert a string to a signed long long
106 * @cp: The start of the string
107 * @endp: A pointer to the end of the parsed string will be placed here
108 * @base: The number base to use
109 *
110 * This function is obsolete. Please use kstrtoll instead.
111 */
112long long simple_strtoll(const char *cp, char **endp, unsigned int base)
113{
114 if (*cp == '-')
115 return -simple_strtoull(cp + 1, endp, base);
116
117 return simple_strtoull(cp, endp, base);
118}
119EXPORT_SYMBOL(simple_strtoll);
120
121static noinline_for_stack
122int skip_atoi(const char **s)
123{
124 int i = 0;
125
126 do {
127 i = i*10 + *((*s)++) - '0';
128 } while (isdigit(**s));
129
130 return i;
131}
132
133/*
134 * Decimal conversion is by far the most typical, and is used for
135 * /proc and /sys data. This directly impacts e.g. top performance
136 * with many processes running. We optimize it for speed by emitting
137 * two characters at a time, using a 200 byte lookup table. This
138 * roughly halves the number of multiplications compared to computing
139 * the digits one at a time. Implementation strongly inspired by the
140 * previous version, which in turn used ideas described at
141 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
142 * from the author, Douglas W. Jones).
143 *
144 * It turns out there is precisely one 26 bit fixed-point
145 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
146 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
147 * range happens to be somewhat larger (x <= 1073741898), but that's
148 * irrelevant for our purpose.
149 *
150 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
151 * need a 32x32->64 bit multiply, so we simply use the same constant.
152 *
153 * For dividing a number in the range [100, 10^4-1] by 100, there are
154 * several options. The simplest is (x * 0x147b) >> 19, which is valid
155 * for all x <= 43698.
156 */
157
158static const u16 decpair[100] = {
159#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
160 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
161 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
162 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
163 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
164 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
165 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
166 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
167 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
168 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
169 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
170#undef _
171};
172
173/*
174 * This will print a single '0' even if r == 0, since we would
175 * immediately jump to out_r where two 0s would be written but only
176 * one of them accounted for in buf. This is needed by ip4_string
177 * below. All other callers pass a non-zero value of r.
178*/
179static noinline_for_stack
180char *put_dec_trunc8(char *buf, unsigned r)
181{
182 unsigned q;
183
184 /* 1 <= r < 10^8 */
185 if (r < 100)
186 goto out_r;
187
188 /* 100 <= r < 10^8 */
189 q = (r * (u64)0x28f5c29) >> 32;
190 *((u16 *)buf) = decpair[r - 100*q];
191 buf += 2;
192
193 /* 1 <= q < 10^6 */
194 if (q < 100)
195 goto out_q;
196
197 /* 100 <= q < 10^6 */
198 r = (q * (u64)0x28f5c29) >> 32;
199 *((u16 *)buf) = decpair[q - 100*r];
200 buf += 2;
201
202 /* 1 <= r < 10^4 */
203 if (r < 100)
204 goto out_r;
205
206 /* 100 <= r < 10^4 */
207 q = (r * 0x147b) >> 19;
208 *((u16 *)buf) = decpair[r - 100*q];
209 buf += 2;
210out_q:
211 /* 1 <= q < 100 */
212 r = q;
213out_r:
214 /* 1 <= r < 100 */
215 *((u16 *)buf) = decpair[r];
216 buf += r < 10 ? 1 : 2;
217 return buf;
218}
219
220#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
221static noinline_for_stack
222char *put_dec_full8(char *buf, unsigned r)
223{
224 unsigned q;
225
226 /* 0 <= r < 10^8 */
227 q = (r * (u64)0x28f5c29) >> 32;
228 *((u16 *)buf) = decpair[r - 100*q];
229 buf += 2;
230
231 /* 0 <= q < 10^6 */
232 r = (q * (u64)0x28f5c29) >> 32;
233 *((u16 *)buf) = decpair[q - 100*r];
234 buf += 2;
235
236 /* 0 <= r < 10^4 */
237 q = (r * 0x147b) >> 19;
238 *((u16 *)buf) = decpair[r - 100*q];
239 buf += 2;
240
241 /* 0 <= q < 100 */
242 *((u16 *)buf) = decpair[q];
243 buf += 2;
244 return buf;
245}
246
247static noinline_for_stack
248char *put_dec(char *buf, unsigned long long n)
249{
250 if (n >= 100*1000*1000)
251 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
252 /* 1 <= n <= 1.6e11 */
253 if (n >= 100*1000*1000)
254 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
255 /* 1 <= n < 1e8 */
256 return put_dec_trunc8(buf, n);
257}
258
259#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
260
261static void
262put_dec_full4(char *buf, unsigned r)
263{
264 unsigned q;
265
266 /* 0 <= r < 10^4 */
267 q = (r * 0x147b) >> 19;
268 *((u16 *)buf) = decpair[r - 100*q];
269 buf += 2;
270 /* 0 <= q < 100 */
271 *((u16 *)buf) = decpair[q];
272}
273
274/*
275 * Call put_dec_full4 on x % 10000, return x / 10000.
276 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
277 * holds for all x < 1,128,869,999. The largest value this
278 * helper will ever be asked to convert is 1,125,520,955.
279 * (second call in the put_dec code, assuming n is all-ones).
280 */
281static noinline_for_stack
282unsigned put_dec_helper4(char *buf, unsigned x)
283{
284 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
285
286 put_dec_full4(buf, x - q * 10000);
287 return q;
288}
289
290/* Based on code by Douglas W. Jones found at
291 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
292 * (with permission from the author).
293 * Performs no 64-bit division and hence should be fast on 32-bit machines.
294 */
295static
296char *put_dec(char *buf, unsigned long long n)
297{
298 uint32_t d3, d2, d1, q, h;
299
300 if (n < 100*1000*1000)
301 return put_dec_trunc8(buf, n);
302
303 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
304 h = (n >> 32);
305 d2 = (h ) & 0xffff;
306 d3 = (h >> 16); /* implicit "& 0xffff" */
307
308 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
309 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
310 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
311 q = put_dec_helper4(buf, q);
312
313 q += 7671 * d3 + 9496 * d2 + 6 * d1;
314 q = put_dec_helper4(buf+4, q);
315
316 q += 4749 * d3 + 42 * d2;
317 q = put_dec_helper4(buf+8, q);
318
319 q += 281 * d3;
320 buf += 12;
321 if (q)
322 buf = put_dec_trunc8(buf, q);
323 else while (buf[-1] == '0')
324 --buf;
325
326 return buf;
327}
328
329#endif
330
331/*
332 * Convert passed number to decimal string.
333 * Returns the length of string. On buffer overflow, returns 0.
334 *
335 * If speed is not important, use snprintf(). It's easy to read the code.
336 */
337int num_to_str(char *buf, int size, unsigned long long num)
338{
339 /* put_dec requires 2-byte alignment of the buffer. */
340 char tmp[sizeof(num) * 3] __aligned(2);
341 int idx, len;
342
343 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
344 if (num <= 9) {
345 tmp[0] = '0' + num;
346 len = 1;
347 } else {
348 len = put_dec(tmp, num) - tmp;
349 }
350
351 if (len > size)
352 return 0;
353 for (idx = 0; idx < len; ++idx)
354 buf[idx] = tmp[len - idx - 1];
355 return len;
356}
357
358#define SIGN 1 /* unsigned/signed, must be 1 */
359#define LEFT 2 /* left justified */
360#define PLUS 4 /* show plus */
361#define SPACE 8 /* space if plus */
362#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
363#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
364#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
365
366enum format_type {
367 FORMAT_TYPE_NONE, /* Just a string part */
368 FORMAT_TYPE_WIDTH,
369 FORMAT_TYPE_PRECISION,
370 FORMAT_TYPE_CHAR,
371 FORMAT_TYPE_STR,
372 FORMAT_TYPE_PTR,
373 FORMAT_TYPE_PERCENT_CHAR,
374 FORMAT_TYPE_INVALID,
375 FORMAT_TYPE_LONG_LONG,
376 FORMAT_TYPE_ULONG,
377 FORMAT_TYPE_LONG,
378 FORMAT_TYPE_UBYTE,
379 FORMAT_TYPE_BYTE,
380 FORMAT_TYPE_USHORT,
381 FORMAT_TYPE_SHORT,
382 FORMAT_TYPE_UINT,
383 FORMAT_TYPE_INT,
384 FORMAT_TYPE_SIZE_T,
385 FORMAT_TYPE_PTRDIFF
386};
387
388struct printf_spec {
389 unsigned int type:8; /* format_type enum */
390 signed int field_width:24; /* width of output field */
391 unsigned int flags:8; /* flags to number() */
392 unsigned int base:8; /* number base, 8, 10 or 16 only */
393 signed int precision:16; /* # of digits/chars */
394} __packed;
395#define FIELD_WIDTH_MAX ((1 << 23) - 1)
396#define PRECISION_MAX ((1 << 15) - 1)
397
398static noinline_for_stack
399char *number(char *buf, char *end, unsigned long long num,
400 struct printf_spec spec)
401{
402 /* put_dec requires 2-byte alignment of the buffer. */
403 char tmp[3 * sizeof(num)] __aligned(2);
404 char sign;
405 char locase;
406 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
407 int i;
408 bool is_zero = num == 0LL;
409 int field_width = spec.field_width;
410 int precision = spec.precision;
411
412 BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
413
414 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
415 * produces same digits or (maybe lowercased) letters */
416 locase = (spec.flags & SMALL);
417 if (spec.flags & LEFT)
418 spec.flags &= ~ZEROPAD;
419 sign = 0;
420 if (spec.flags & SIGN) {
421 if ((signed long long)num < 0) {
422 sign = '-';
423 num = -(signed long long)num;
424 field_width--;
425 } else if (spec.flags & PLUS) {
426 sign = '+';
427 field_width--;
428 } else if (spec.flags & SPACE) {
429 sign = ' ';
430 field_width--;
431 }
432 }
433 if (need_pfx) {
434 if (spec.base == 16)
435 field_width -= 2;
436 else if (!is_zero)
437 field_width--;
438 }
439
440 /* generate full string in tmp[], in reverse order */
441 i = 0;
442 if (num < spec.base)
443 tmp[i++] = hex_asc_upper[num] | locase;
444 else if (spec.base != 10) { /* 8 or 16 */
445 int mask = spec.base - 1;
446 int shift = 3;
447
448 if (spec.base == 16)
449 shift = 4;
450 do {
451 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
452 num >>= shift;
453 } while (num);
454 } else { /* base 10 */
455 i = put_dec(tmp, num) - tmp;
456 }
457
458 /* printing 100 using %2d gives "100", not "00" */
459 if (i > precision)
460 precision = i;
461 /* leading space padding */
462 field_width -= precision;
463 if (!(spec.flags & (ZEROPAD | LEFT))) {
464 while (--field_width >= 0) {
465 if (buf < end)
466 *buf = ' ';
467 ++buf;
468 }
469 }
470 /* sign */
471 if (sign) {
472 if (buf < end)
473 *buf = sign;
474 ++buf;
475 }
476 /* "0x" / "0" prefix */
477 if (need_pfx) {
478 if (spec.base == 16 || !is_zero) {
479 if (buf < end)
480 *buf = '0';
481 ++buf;
482 }
483 if (spec.base == 16) {
484 if (buf < end)
485 *buf = ('X' | locase);
486 ++buf;
487 }
488 }
489 /* zero or space padding */
490 if (!(spec.flags & LEFT)) {
491 char c = ' ' + (spec.flags & ZEROPAD);
492 BUILD_BUG_ON(' ' + ZEROPAD != '0');
493 while (--field_width >= 0) {
494 if (buf < end)
495 *buf = c;
496 ++buf;
497 }
498 }
499 /* hmm even more zero padding? */
500 while (i <= --precision) {
501 if (buf < end)
502 *buf = '0';
503 ++buf;
504 }
505 /* actual digits of result */
506 while (--i >= 0) {
507 if (buf < end)
508 *buf = tmp[i];
509 ++buf;
510 }
511 /* trailing space padding */
512 while (--field_width >= 0) {
513 if (buf < end)
514 *buf = ' ';
515 ++buf;
516 }
517
518 return buf;
519}
520
521static noinline_for_stack
522char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
523{
524 struct printf_spec spec;
525
526 spec.type = FORMAT_TYPE_PTR;
527 spec.field_width = 2 + 2 * size; /* 0x + hex */
528 spec.flags = SPECIAL | SMALL | ZEROPAD;
529 spec.base = 16;
530 spec.precision = -1;
531
532 return number(buf, end, num, spec);
533}
534
535static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
536{
537 size_t size;
538 if (buf >= end) /* nowhere to put anything */
539 return;
540 size = end - buf;
541 if (size <= spaces) {
542 memset(buf, ' ', size);
543 return;
544 }
545 if (len) {
546 if (len > size - spaces)
547 len = size - spaces;
548 memmove(buf + spaces, buf, len);
549 }
550 memset(buf, ' ', spaces);
551}
552
553/*
554 * Handle field width padding for a string.
555 * @buf: current buffer position
556 * @n: length of string
557 * @end: end of output buffer
558 * @spec: for field width and flags
559 * Returns: new buffer position after padding.
560 */
561static noinline_for_stack
562char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
563{
564 unsigned spaces;
565
566 if (likely(n >= spec.field_width))
567 return buf;
568 /* we want to pad the sucker */
569 spaces = spec.field_width - n;
570 if (!(spec.flags & LEFT)) {
571 move_right(buf - n, end, n, spaces);
572 return buf + spaces;
573 }
574 while (spaces--) {
575 if (buf < end)
576 *buf = ' ';
577 ++buf;
578 }
579 return buf;
580}
581
582static noinline_for_stack
583char *string(char *buf, char *end, const char *s, struct printf_spec spec)
584{
585 int len = 0;
586 size_t lim = spec.precision;
587
588 if ((unsigned long)s < PAGE_SIZE)
589 s = "(null)";
590
591 while (lim--) {
592 char c = *s++;
593 if (!c)
594 break;
595 if (buf < end)
596 *buf = c;
597 ++buf;
598 ++len;
599 }
600 return widen_string(buf, len, end, spec);
601}
602
603static noinline_for_stack
604char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
605 const char *fmt)
606{
607 const char *array[4], *s;
608 const struct dentry *p;
609 int depth;
610 int i, n;
611
612 switch (fmt[1]) {
613 case '2': case '3': case '4':
614 depth = fmt[1] - '0';
615 break;
616 default:
617 depth = 1;
618 }
619
620 rcu_read_lock();
621 for (i = 0; i < depth; i++, d = p) {
622 p = ACCESS_ONCE(d->d_parent);
623 array[i] = ACCESS_ONCE(d->d_name.name);
624 if (p == d) {
625 if (i)
626 array[i] = "";
627 i++;
628 break;
629 }
630 }
631 s = array[--i];
632 for (n = 0; n != spec.precision; n++, buf++) {
633 char c = *s++;
634 if (!c) {
635 if (!i)
636 break;
637 c = '/';
638 s = array[--i];
639 }
640 if (buf < end)
641 *buf = c;
642 }
643 rcu_read_unlock();
644 return widen_string(buf, n, end, spec);
645}
646
647#ifdef CONFIG_BLOCK
648static noinline_for_stack
649char *bdev_name(char *buf, char *end, struct block_device *bdev,
650 struct printf_spec spec, const char *fmt)
651{
652 struct gendisk *hd = bdev->bd_disk;
653
654 buf = string(buf, end, hd->disk_name, spec);
655 if (bdev->bd_part->partno) {
656 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
657 if (buf < end)
658 *buf = 'p';
659 buf++;
660 }
661 buf = number(buf, end, bdev->bd_part->partno, spec);
662 }
663 return buf;
664}
665#endif
666
667static noinline_for_stack
668char *symbol_string(char *buf, char *end, void *ptr,
669 struct printf_spec spec, const char *fmt)
670{
671 unsigned long value;
672#ifdef CONFIG_KALLSYMS
673 char sym[KSYM_SYMBOL_LEN];
674#endif
675
676 if (fmt[1] == 'R')
677 ptr = __builtin_extract_return_addr(ptr);
678 value = (unsigned long)ptr;
679
680#ifdef CONFIG_KALLSYMS
681 if (*fmt == 'B')
682 sprint_backtrace(sym, value);
683 else if (*fmt != 'f' && *fmt != 's')
684 sprint_symbol(sym, value);
685 else
686 sprint_symbol_no_offset(sym, value);
687
688 return string(buf, end, sym, spec);
689#else
690 return special_hex_number(buf, end, value, sizeof(void *));
691#endif
692}
693
694static noinline_for_stack
695char *resource_string(char *buf, char *end, struct resource *res,
696 struct printf_spec spec, const char *fmt)
697{
698#ifndef IO_RSRC_PRINTK_SIZE
699#define IO_RSRC_PRINTK_SIZE 6
700#endif
701
702#ifndef MEM_RSRC_PRINTK_SIZE
703#define MEM_RSRC_PRINTK_SIZE 10
704#endif
705 static const struct printf_spec io_spec = {
706 .base = 16,
707 .field_width = IO_RSRC_PRINTK_SIZE,
708 .precision = -1,
709 .flags = SPECIAL | SMALL | ZEROPAD,
710 };
711 static const struct printf_spec mem_spec = {
712 .base = 16,
713 .field_width = MEM_RSRC_PRINTK_SIZE,
714 .precision = -1,
715 .flags = SPECIAL | SMALL | ZEROPAD,
716 };
717 static const struct printf_spec bus_spec = {
718 .base = 16,
719 .field_width = 2,
720 .precision = -1,
721 .flags = SMALL | ZEROPAD,
722 };
723 static const struct printf_spec dec_spec = {
724 .base = 10,
725 .precision = -1,
726 .flags = 0,
727 };
728 static const struct printf_spec str_spec = {
729 .field_width = -1,
730 .precision = 10,
731 .flags = LEFT,
732 };
733 static const struct printf_spec flag_spec = {
734 .base = 16,
735 .precision = -1,
736 .flags = SPECIAL | SMALL,
737 };
738
739 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
740 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
741#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
742#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
743#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
744#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
745 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
746 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
747
748 char *p = sym, *pend = sym + sizeof(sym);
749 int decode = (fmt[0] == 'R') ? 1 : 0;
750 const struct printf_spec *specp;
751
752 *p++ = '[';
753 if (res->flags & IORESOURCE_IO) {
754 p = string(p, pend, "io ", str_spec);
755 specp = &io_spec;
756 } else if (res->flags & IORESOURCE_MEM) {
757 p = string(p, pend, "mem ", str_spec);
758 specp = &mem_spec;
759 } else if (res->flags & IORESOURCE_IRQ) {
760 p = string(p, pend, "irq ", str_spec);
761 specp = &dec_spec;
762 } else if (res->flags & IORESOURCE_DMA) {
763 p = string(p, pend, "dma ", str_spec);
764 specp = &dec_spec;
765 } else if (res->flags & IORESOURCE_BUS) {
766 p = string(p, pend, "bus ", str_spec);
767 specp = &bus_spec;
768 } else {
769 p = string(p, pend, "??? ", str_spec);
770 specp = &mem_spec;
771 decode = 0;
772 }
773 if (decode && res->flags & IORESOURCE_UNSET) {
774 p = string(p, pend, "size ", str_spec);
775 p = number(p, pend, resource_size(res), *specp);
776 } else {
777 p = number(p, pend, res->start, *specp);
778 if (res->start != res->end) {
779 *p++ = '-';
780 p = number(p, pend, res->end, *specp);
781 }
782 }
783 if (decode) {
784 if (res->flags & IORESOURCE_MEM_64)
785 p = string(p, pend, " 64bit", str_spec);
786 if (res->flags & IORESOURCE_PREFETCH)
787 p = string(p, pend, " pref", str_spec);
788 if (res->flags & IORESOURCE_WINDOW)
789 p = string(p, pend, " window", str_spec);
790 if (res->flags & IORESOURCE_DISABLED)
791 p = string(p, pend, " disabled", str_spec);
792 } else {
793 p = string(p, pend, " flags ", str_spec);
794 p = number(p, pend, res->flags, flag_spec);
795 }
796 *p++ = ']';
797 *p = '\0';
798
799 return string(buf, end, sym, spec);
800}
801
802static noinline_for_stack
803char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
804 const char *fmt)
805{
806 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
807 negative value, fallback to the default */
808 char separator;
809
810 if (spec.field_width == 0)
811 /* nothing to print */
812 return buf;
813
814 if (ZERO_OR_NULL_PTR(addr))
815 /* NULL pointer */
816 return string(buf, end, NULL, spec);
817
818 switch (fmt[1]) {
819 case 'C':
820 separator = ':';
821 break;
822 case 'D':
823 separator = '-';
824 break;
825 case 'N':
826 separator = 0;
827 break;
828 default:
829 separator = ' ';
830 break;
831 }
832
833 if (spec.field_width > 0)
834 len = min_t(int, spec.field_width, 64);
835
836 for (i = 0; i < len; ++i) {
837 if (buf < end)
838 *buf = hex_asc_hi(addr[i]);
839 ++buf;
840 if (buf < end)
841 *buf = hex_asc_lo(addr[i]);
842 ++buf;
843
844 if (separator && i != len - 1) {
845 if (buf < end)
846 *buf = separator;
847 ++buf;
848 }
849 }
850
851 return buf;
852}
853
854static noinline_for_stack
855char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
856 struct printf_spec spec, const char *fmt)
857{
858 const int CHUNKSZ = 32;
859 int nr_bits = max_t(int, spec.field_width, 0);
860 int i, chunksz;
861 bool first = true;
862
863 /* reused to print numbers */
864 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
865
866 chunksz = nr_bits & (CHUNKSZ - 1);
867 if (chunksz == 0)
868 chunksz = CHUNKSZ;
869
870 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
871 for (; i >= 0; i -= CHUNKSZ) {
872 u32 chunkmask, val;
873 int word, bit;
874
875 chunkmask = ((1ULL << chunksz) - 1);
876 word = i / BITS_PER_LONG;
877 bit = i % BITS_PER_LONG;
878 val = (bitmap[word] >> bit) & chunkmask;
879
880 if (!first) {
881 if (buf < end)
882 *buf = ',';
883 buf++;
884 }
885 first = false;
886
887 spec.field_width = DIV_ROUND_UP(chunksz, 4);
888 buf = number(buf, end, val, spec);
889
890 chunksz = CHUNKSZ;
891 }
892 return buf;
893}
894
895static noinline_for_stack
896char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
897 struct printf_spec spec, const char *fmt)
898{
899 int nr_bits = max_t(int, spec.field_width, 0);
900 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
901 int cur, rbot, rtop;
902 bool first = true;
903
904 /* reused to print numbers */
905 spec = (struct printf_spec){ .base = 10 };
906
907 rbot = cur = find_first_bit(bitmap, nr_bits);
908 while (cur < nr_bits) {
909 rtop = cur;
910 cur = find_next_bit(bitmap, nr_bits, cur + 1);
911 if (cur < nr_bits && cur <= rtop + 1)
912 continue;
913
914 if (!first) {
915 if (buf < end)
916 *buf = ',';
917 buf++;
918 }
919 first = false;
920
921 buf = number(buf, end, rbot, spec);
922 if (rbot < rtop) {
923 if (buf < end)
924 *buf = '-';
925 buf++;
926
927 buf = number(buf, end, rtop, spec);
928 }
929
930 rbot = cur;
931 }
932 return buf;
933}
934
935static noinline_for_stack
936char *mac_address_string(char *buf, char *end, u8 *addr,
937 struct printf_spec spec, const char *fmt)
938{
939 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
940 char *p = mac_addr;
941 int i;
942 char separator;
943 bool reversed = false;
944
945 switch (fmt[1]) {
946 case 'F':
947 separator = '-';
948 break;
949
950 case 'R':
951 reversed = true;
952 /* fall through */
953
954 default:
955 separator = ':';
956 break;
957 }
958
959 for (i = 0; i < 6; i++) {
960 if (reversed)
961 p = hex_byte_pack(p, addr[5 - i]);
962 else
963 p = hex_byte_pack(p, addr[i]);
964
965 if (fmt[0] == 'M' && i != 5)
966 *p++ = separator;
967 }
968 *p = '\0';
969
970 return string(buf, end, mac_addr, spec);
971}
972
973static noinline_for_stack
974char *ip4_string(char *p, const u8 *addr, const char *fmt)
975{
976 int i;
977 bool leading_zeros = (fmt[0] == 'i');
978 int index;
979 int step;
980
981 switch (fmt[2]) {
982 case 'h':
983#ifdef __BIG_ENDIAN
984 index = 0;
985 step = 1;
986#else
987 index = 3;
988 step = -1;
989#endif
990 break;
991 case 'l':
992 index = 3;
993 step = -1;
994 break;
995 case 'n':
996 case 'b':
997 default:
998 index = 0;
999 step = 1;
1000 break;
1001 }
1002 for (i = 0; i < 4; i++) {
1003 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1004 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1005 if (leading_zeros) {
1006 if (digits < 3)
1007 *p++ = '0';
1008 if (digits < 2)
1009 *p++ = '0';
1010 }
1011 /* reverse the digits in the quad */
1012 while (digits--)
1013 *p++ = temp[digits];
1014 if (i < 3)
1015 *p++ = '.';
1016 index += step;
1017 }
1018 *p = '\0';
1019
1020 return p;
1021}
1022
1023static noinline_for_stack
1024char *ip6_compressed_string(char *p, const char *addr)
1025{
1026 int i, j, range;
1027 unsigned char zerolength[8];
1028 int longest = 1;
1029 int colonpos = -1;
1030 u16 word;
1031 u8 hi, lo;
1032 bool needcolon = false;
1033 bool useIPv4;
1034 struct in6_addr in6;
1035
1036 memcpy(&in6, addr, sizeof(struct in6_addr));
1037
1038 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1039
1040 memset(zerolength, 0, sizeof(zerolength));
1041
1042 if (useIPv4)
1043 range = 6;
1044 else
1045 range = 8;
1046
1047 /* find position of longest 0 run */
1048 for (i = 0; i < range; i++) {
1049 for (j = i; j < range; j++) {
1050 if (in6.s6_addr16[j] != 0)
1051 break;
1052 zerolength[i]++;
1053 }
1054 }
1055 for (i = 0; i < range; i++) {
1056 if (zerolength[i] > longest) {
1057 longest = zerolength[i];
1058 colonpos = i;
1059 }
1060 }
1061 if (longest == 1) /* don't compress a single 0 */
1062 colonpos = -1;
1063
1064 /* emit address */
1065 for (i = 0; i < range; i++) {
1066 if (i == colonpos) {
1067 if (needcolon || i == 0)
1068 *p++ = ':';
1069 *p++ = ':';
1070 needcolon = false;
1071 i += longest - 1;
1072 continue;
1073 }
1074 if (needcolon) {
1075 *p++ = ':';
1076 needcolon = false;
1077 }
1078 /* hex u16 without leading 0s */
1079 word = ntohs(in6.s6_addr16[i]);
1080 hi = word >> 8;
1081 lo = word & 0xff;
1082 if (hi) {
1083 if (hi > 0x0f)
1084 p = hex_byte_pack(p, hi);
1085 else
1086 *p++ = hex_asc_lo(hi);
1087 p = hex_byte_pack(p, lo);
1088 }
1089 else if (lo > 0x0f)
1090 p = hex_byte_pack(p, lo);
1091 else
1092 *p++ = hex_asc_lo(lo);
1093 needcolon = true;
1094 }
1095
1096 if (useIPv4) {
1097 if (needcolon)
1098 *p++ = ':';
1099 p = ip4_string(p, &in6.s6_addr[12], "I4");
1100 }
1101 *p = '\0';
1102
1103 return p;
1104}
1105
1106static noinline_for_stack
1107char *ip6_string(char *p, const char *addr, const char *fmt)
1108{
1109 int i;
1110
1111 for (i = 0; i < 8; i++) {
1112 p = hex_byte_pack(p, *addr++);
1113 p = hex_byte_pack(p, *addr++);
1114 if (fmt[0] == 'I' && i != 7)
1115 *p++ = ':';
1116 }
1117 *p = '\0';
1118
1119 return p;
1120}
1121
1122static noinline_for_stack
1123char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1124 struct printf_spec spec, const char *fmt)
1125{
1126 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1127
1128 if (fmt[0] == 'I' && fmt[2] == 'c')
1129 ip6_compressed_string(ip6_addr, addr);
1130 else
1131 ip6_string(ip6_addr, addr, fmt);
1132
1133 return string(buf, end, ip6_addr, spec);
1134}
1135
1136static noinline_for_stack
1137char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1138 struct printf_spec spec, const char *fmt)
1139{
1140 char ip4_addr[sizeof("255.255.255.255")];
1141
1142 ip4_string(ip4_addr, addr, fmt);
1143
1144 return string(buf, end, ip4_addr, spec);
1145}
1146
1147static noinline_for_stack
1148char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1149 struct printf_spec spec, const char *fmt)
1150{
1151 bool have_p = false, have_s = false, have_f = false, have_c = false;
1152 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1153 sizeof(":12345") + sizeof("/123456789") +
1154 sizeof("%1234567890")];
1155 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1156 const u8 *addr = (const u8 *) &sa->sin6_addr;
1157 char fmt6[2] = { fmt[0], '6' };
1158 u8 off = 0;
1159
1160 fmt++;
1161 while (isalpha(*++fmt)) {
1162 switch (*fmt) {
1163 case 'p':
1164 have_p = true;
1165 break;
1166 case 'f':
1167 have_f = true;
1168 break;
1169 case 's':
1170 have_s = true;
1171 break;
1172 case 'c':
1173 have_c = true;
1174 break;
1175 }
1176 }
1177
1178 if (have_p || have_s || have_f) {
1179 *p = '[';
1180 off = 1;
1181 }
1182
1183 if (fmt6[0] == 'I' && have_c)
1184 p = ip6_compressed_string(ip6_addr + off, addr);
1185 else
1186 p = ip6_string(ip6_addr + off, addr, fmt6);
1187
1188 if (have_p || have_s || have_f)
1189 *p++ = ']';
1190
1191 if (have_p) {
1192 *p++ = ':';
1193 p = number(p, pend, ntohs(sa->sin6_port), spec);
1194 }
1195 if (have_f) {
1196 *p++ = '/';
1197 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1198 IPV6_FLOWINFO_MASK), spec);
1199 }
1200 if (have_s) {
1201 *p++ = '%';
1202 p = number(p, pend, sa->sin6_scope_id, spec);
1203 }
1204 *p = '\0';
1205
1206 return string(buf, end, ip6_addr, spec);
1207}
1208
1209static noinline_for_stack
1210char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1211 struct printf_spec spec, const char *fmt)
1212{
1213 bool have_p = false;
1214 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1215 char *pend = ip4_addr + sizeof(ip4_addr);
1216 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1217 char fmt4[3] = { fmt[0], '4', 0 };
1218
1219 fmt++;
1220 while (isalpha(*++fmt)) {
1221 switch (*fmt) {
1222 case 'p':
1223 have_p = true;
1224 break;
1225 case 'h':
1226 case 'l':
1227 case 'n':
1228 case 'b':
1229 fmt4[2] = *fmt;
1230 break;
1231 }
1232 }
1233
1234 p = ip4_string(ip4_addr, addr, fmt4);
1235 if (have_p) {
1236 *p++ = ':';
1237 p = number(p, pend, ntohs(sa->sin_port), spec);
1238 }
1239 *p = '\0';
1240
1241 return string(buf, end, ip4_addr, spec);
1242}
1243
1244static noinline_for_stack
1245char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1246 const char *fmt)
1247{
1248 bool found = true;
1249 int count = 1;
1250 unsigned int flags = 0;
1251 int len;
1252
1253 if (spec.field_width == 0)
1254 return buf; /* nothing to print */
1255
1256 if (ZERO_OR_NULL_PTR(addr))
1257 return string(buf, end, NULL, spec); /* NULL pointer */
1258
1259
1260 do {
1261 switch (fmt[count++]) {
1262 case 'a':
1263 flags |= ESCAPE_ANY;
1264 break;
1265 case 'c':
1266 flags |= ESCAPE_SPECIAL;
1267 break;
1268 case 'h':
1269 flags |= ESCAPE_HEX;
1270 break;
1271 case 'n':
1272 flags |= ESCAPE_NULL;
1273 break;
1274 case 'o':
1275 flags |= ESCAPE_OCTAL;
1276 break;
1277 case 'p':
1278 flags |= ESCAPE_NP;
1279 break;
1280 case 's':
1281 flags |= ESCAPE_SPACE;
1282 break;
1283 default:
1284 found = false;
1285 break;
1286 }
1287 } while (found);
1288
1289 if (!flags)
1290 flags = ESCAPE_ANY_NP;
1291
1292 len = spec.field_width < 0 ? 1 : spec.field_width;
1293
1294 /*
1295 * string_escape_mem() writes as many characters as it can to
1296 * the given buffer, and returns the total size of the output
1297 * had the buffer been big enough.
1298 */
1299 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1300
1301 return buf;
1302}
1303
1304static noinline_for_stack
1305char *uuid_string(char *buf, char *end, const u8 *addr,
1306 struct printf_spec spec, const char *fmt)
1307{
1308 char uuid[UUID_STRING_LEN + 1];
1309 char *p = uuid;
1310 int i;
1311 const u8 *index = uuid_be_index;
1312 bool uc = false;
1313
1314 switch (*(++fmt)) {
1315 case 'L':
1316 uc = true; /* fall-through */
1317 case 'l':
1318 index = uuid_le_index;
1319 break;
1320 case 'B':
1321 uc = true;
1322 break;
1323 }
1324
1325 for (i = 0; i < 16; i++) {
1326 if (uc)
1327 p = hex_byte_pack_upper(p, addr[index[i]]);
1328 else
1329 p = hex_byte_pack(p, addr[index[i]]);
1330 switch (i) {
1331 case 3:
1332 case 5:
1333 case 7:
1334 case 9:
1335 *p++ = '-';
1336 break;
1337 }
1338 }
1339
1340 *p = 0;
1341
1342 return string(buf, end, uuid, spec);
1343}
1344
1345static noinline_for_stack
1346char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1347{
1348 unsigned long long num;
1349 int size;
1350
1351 switch (fmt[1]) {
1352 case 'F':
1353 num = *(const netdev_features_t *)addr;
1354 size = sizeof(netdev_features_t);
1355 break;
1356 default:
1357 num = (unsigned long)addr;
1358 size = sizeof(unsigned long);
1359 break;
1360 }
1361
1362 return special_hex_number(buf, end, num, size);
1363}
1364
1365static noinline_for_stack
1366char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1367{
1368 unsigned long long num;
1369 int size;
1370
1371 switch (fmt[1]) {
1372 case 'd':
1373 num = *(const dma_addr_t *)addr;
1374 size = sizeof(dma_addr_t);
1375 break;
1376 case 'p':
1377 default:
1378 num = *(const phys_addr_t *)addr;
1379 size = sizeof(phys_addr_t);
1380 break;
1381 }
1382
1383 return special_hex_number(buf, end, num, size);
1384}
1385
1386static noinline_for_stack
1387char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1388 const char *fmt)
1389{
1390 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1391 return string(buf, end, NULL, spec);
1392
1393 switch (fmt[1]) {
1394 case 'r':
1395 return number(buf, end, clk_get_rate(clk), spec);
1396
1397 case 'n':
1398 default:
1399#ifdef CONFIG_COMMON_CLK
1400 return string(buf, end, __clk_get_name(clk), spec);
1401#else
1402 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1403#endif
1404 }
1405}
1406
1407static
1408char *format_flags(char *buf, char *end, unsigned long flags,
1409 const struct trace_print_flags *names)
1410{
1411 unsigned long mask;
1412 const struct printf_spec strspec = {
1413 .field_width = -1,
1414 .precision = -1,
1415 };
1416 const struct printf_spec numspec = {
1417 .flags = SPECIAL|SMALL,
1418 .field_width = -1,
1419 .precision = -1,
1420 .base = 16,
1421 };
1422
1423 for ( ; flags && names->name; names++) {
1424 mask = names->mask;
1425 if ((flags & mask) != mask)
1426 continue;
1427
1428 buf = string(buf, end, names->name, strspec);
1429
1430 flags &= ~mask;
1431 if (flags) {
1432 if (buf < end)
1433 *buf = '|';
1434 buf++;
1435 }
1436 }
1437
1438 if (flags)
1439 buf = number(buf, end, flags, numspec);
1440
1441 return buf;
1442}
1443
1444static noinline_for_stack
1445char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1446{
1447 unsigned long flags;
1448 const struct trace_print_flags *names;
1449
1450 switch (fmt[1]) {
1451 case 'p':
1452 flags = *(unsigned long *)flags_ptr;
1453 /* Remove zone id */
1454 flags &= (1UL << NR_PAGEFLAGS) - 1;
1455 names = pageflag_names;
1456 break;
1457 case 'v':
1458 flags = *(unsigned long *)flags_ptr;
1459 names = vmaflag_names;
1460 break;
1461 case 'g':
1462 flags = *(gfp_t *)flags_ptr;
1463 names = gfpflag_names;
1464 break;
1465 default:
1466 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1467 return buf;
1468 }
1469
1470 return format_flags(buf, end, flags, names);
1471}
1472
1473int kptr_restrict __read_mostly;
1474
1475/*
1476 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1477 * by an extra set of alphanumeric characters that are extended format
1478 * specifiers.
1479 *
1480 * Right now we handle:
1481 *
1482 * - 'F' For symbolic function descriptor pointers with offset
1483 * - 'f' For simple symbolic function names without offset
1484 * - 'S' For symbolic direct pointers with offset
1485 * - 's' For symbolic direct pointers without offset
1486 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1487 * - 'B' For backtraced symbolic direct pointers with offset
1488 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1489 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1490 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1491 * width which must be explicitly specified either as part of the
1492 * format string '%32b[l]' or through '%*b[l]', [l] selects
1493 * range-list format instead of hex format
1494 * - 'M' For a 6-byte MAC address, it prints the address in the
1495 * usual colon-separated hex notation
1496 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1497 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1498 * with a dash-separated hex notation
1499 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1500 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1501 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1502 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1503 * [S][pfs]
1504 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1505 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1506 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1507 * IPv6 omits the colons (01020304...0f)
1508 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1509 * [S][pfs]
1510 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1511 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1512 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1513 * - 'I[6S]c' for IPv6 addresses printed as specified by
1514 * http://tools.ietf.org/html/rfc5952
1515 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1516 * of the following flags (see string_escape_mem() for the
1517 * details):
1518 * a - ESCAPE_ANY
1519 * c - ESCAPE_SPECIAL
1520 * h - ESCAPE_HEX
1521 * n - ESCAPE_NULL
1522 * o - ESCAPE_OCTAL
1523 * p - ESCAPE_NP
1524 * s - ESCAPE_SPACE
1525 * By default ESCAPE_ANY_NP is used.
1526 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1527 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1528 * Options for %pU are:
1529 * b big endian lower case hex (default)
1530 * B big endian UPPER case hex
1531 * l little endian lower case hex
1532 * L little endian UPPER case hex
1533 * big endian output byte order is:
1534 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1535 * little endian output byte order is:
1536 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1537 * - 'V' For a struct va_format which contains a format string * and va_list *,
1538 * call vsnprintf(->format, *->va_list).
1539 * Implements a "recursive vsnprintf".
1540 * Do not use this feature without some mechanism to verify the
1541 * correctness of the format string and va_list arguments.
1542 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1543 * - 'NF' For a netdev_features_t
1544 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1545 * a certain separator (' ' by default):
1546 * C colon
1547 * D dash
1548 * N no separator
1549 * The maximum supported length is 64 bytes of the input. Consider
1550 * to use print_hex_dump() for the larger input.
1551 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1552 * (default assumed to be phys_addr_t, passed by reference)
1553 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1554 * - 'D[234]' Same as 'd' but for a struct file
1555 * - 'g' For block_device name (gendisk + partition number)
1556 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1557 * (legacy clock framework) of the clock
1558 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1559 * (legacy clock framework) of the clock
1560 * - 'Cr' For a clock, it prints the current rate of the clock
1561 * - 'G' For flags to be printed as a collection of symbolic strings that would
1562 * construct the specific value. Supported flags given by option:
1563 * p page flags (see struct page) given as pointer to unsigned long
1564 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1565 * v vma flags (VM_*) given as pointer to unsigned long
1566 *
1567 * ** Please update also Documentation/printk-formats.txt when making changes **
1568 *
1569 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1570 * function pointers are really function descriptors, which contain a
1571 * pointer to the real address.
1572 */
1573static noinline_for_stack
1574char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1575 struct printf_spec spec)
1576{
1577 const int default_width = 2 * sizeof(void *);
1578
1579 if (!ptr && *fmt != 'K') {
1580 /*
1581 * Print (null) with the same width as a pointer so it makes
1582 * tabular output look nice.
1583 */
1584 if (spec.field_width == -1)
1585 spec.field_width = default_width;
1586 return string(buf, end, "(null)", spec);
1587 }
1588
1589 switch (*fmt) {
1590 case 'F':
1591 case 'f':
1592 ptr = dereference_function_descriptor(ptr);
1593 /* Fallthrough */
1594 case 'S':
1595 case 's':
1596 case 'B':
1597 return symbol_string(buf, end, ptr, spec, fmt);
1598 case 'R':
1599 case 'r':
1600 return resource_string(buf, end, ptr, spec, fmt);
1601 case 'h':
1602 return hex_string(buf, end, ptr, spec, fmt);
1603 case 'b':
1604 switch (fmt[1]) {
1605 case 'l':
1606 return bitmap_list_string(buf, end, ptr, spec, fmt);
1607 default:
1608 return bitmap_string(buf, end, ptr, spec, fmt);
1609 }
1610 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1611 case 'm': /* Contiguous: 000102030405 */
1612 /* [mM]F (FDDI) */
1613 /* [mM]R (Reverse order; Bluetooth) */
1614 return mac_address_string(buf, end, ptr, spec, fmt);
1615 case 'I': /* Formatted IP supported
1616 * 4: 1.2.3.4
1617 * 6: 0001:0203:...:0708
1618 * 6c: 1::708 or 1::1.2.3.4
1619 */
1620 case 'i': /* Contiguous:
1621 * 4: 001.002.003.004
1622 * 6: 000102...0f
1623 */
1624 switch (fmt[1]) {
1625 case '6':
1626 return ip6_addr_string(buf, end, ptr, spec, fmt);
1627 case '4':
1628 return ip4_addr_string(buf, end, ptr, spec, fmt);
1629 case 'S': {
1630 const union {
1631 struct sockaddr raw;
1632 struct sockaddr_in v4;
1633 struct sockaddr_in6 v6;
1634 } *sa = ptr;
1635
1636 switch (sa->raw.sa_family) {
1637 case AF_INET:
1638 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1639 case AF_INET6:
1640 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1641 default:
1642 return string(buf, end, "(invalid address)", spec);
1643 }}
1644 }
1645 break;
1646 case 'E':
1647 return escaped_string(buf, end, ptr, spec, fmt);
1648 case 'U':
1649 return uuid_string(buf, end, ptr, spec, fmt);
1650 case 'V':
1651 {
1652 va_list va;
1653
1654 va_copy(va, *((struct va_format *)ptr)->va);
1655 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1656 ((struct va_format *)ptr)->fmt, va);
1657 va_end(va);
1658 return buf;
1659 }
1660 case 'K':
1661 switch (kptr_restrict) {
1662 case 0:
1663 /* Always print %pK values */
1664 break;
1665 case 1: {
1666 const struct cred *cred;
1667
1668 /*
1669 * kptr_restrict==1 cannot be used in IRQ context
1670 * because its test for CAP_SYSLOG would be meaningless.
1671 */
1672 if (in_irq() || in_serving_softirq() || in_nmi()) {
1673 if (spec.field_width == -1)
1674 spec.field_width = default_width;
1675 return string(buf, end, "pK-error", spec);
1676 }
1677
1678 /*
1679 * Only print the real pointer value if the current
1680 * process has CAP_SYSLOG and is running with the
1681 * same credentials it started with. This is because
1682 * access to files is checked at open() time, but %pK
1683 * checks permission at read() time. We don't want to
1684 * leak pointer values if a binary opens a file using
1685 * %pK and then elevates privileges before reading it.
1686 */
1687 cred = current_cred();
1688 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1689 !uid_eq(cred->euid, cred->uid) ||
1690 !gid_eq(cred->egid, cred->gid))
1691 ptr = NULL;
1692 break;
1693 }
1694 case 2:
1695 default:
1696 /* Always print 0's for %pK */
1697 ptr = NULL;
1698 break;
1699 }
1700 break;
1701
1702 case 'N':
1703 return netdev_bits(buf, end, ptr, fmt);
1704 case 'a':
1705 return address_val(buf, end, ptr, fmt);
1706 case 'd':
1707 return dentry_name(buf, end, ptr, spec, fmt);
1708 case 'C':
1709 return clock(buf, end, ptr, spec, fmt);
1710 case 'D':
1711 return dentry_name(buf, end,
1712 ((const struct file *)ptr)->f_path.dentry,
1713 spec, fmt);
1714#ifdef CONFIG_BLOCK
1715 case 'g':
1716 return bdev_name(buf, end, ptr, spec, fmt);
1717#endif
1718
1719 case 'G':
1720 return flags_string(buf, end, ptr, fmt);
1721 }
1722 spec.flags |= SMALL;
1723 if (spec.field_width == -1) {
1724 spec.field_width = default_width;
1725 spec.flags |= ZEROPAD;
1726 }
1727 spec.base = 16;
1728
1729 return number(buf, end, (unsigned long) ptr, spec);
1730}
1731
1732/*
1733 * Helper function to decode printf style format.
1734 * Each call decode a token from the format and return the
1735 * number of characters read (or likely the delta where it wants
1736 * to go on the next call).
1737 * The decoded token is returned through the parameters
1738 *
1739 * 'h', 'l', or 'L' for integer fields
1740 * 'z' support added 23/7/1999 S.H.
1741 * 'z' changed to 'Z' --davidm 1/25/99
1742 * 't' added for ptrdiff_t
1743 *
1744 * @fmt: the format string
1745 * @type of the token returned
1746 * @flags: various flags such as +, -, # tokens..
1747 * @field_width: overwritten width
1748 * @base: base of the number (octal, hex, ...)
1749 * @precision: precision of a number
1750 * @qualifier: qualifier of a number (long, size_t, ...)
1751 */
1752static noinline_for_stack
1753int format_decode(const char *fmt, struct printf_spec *spec)
1754{
1755 const char *start = fmt;
1756 char qualifier;
1757
1758 /* we finished early by reading the field width */
1759 if (spec->type == FORMAT_TYPE_WIDTH) {
1760 if (spec->field_width < 0) {
1761 spec->field_width = -spec->field_width;
1762 spec->flags |= LEFT;
1763 }
1764 spec->type = FORMAT_TYPE_NONE;
1765 goto precision;
1766 }
1767
1768 /* we finished early by reading the precision */
1769 if (spec->type == FORMAT_TYPE_PRECISION) {
1770 if (spec->precision < 0)
1771 spec->precision = 0;
1772
1773 spec->type = FORMAT_TYPE_NONE;
1774 goto qualifier;
1775 }
1776
1777 /* By default */
1778 spec->type = FORMAT_TYPE_NONE;
1779
1780 for (; *fmt ; ++fmt) {
1781 if (*fmt == '%')
1782 break;
1783 }
1784
1785 /* Return the current non-format string */
1786 if (fmt != start || !*fmt)
1787 return fmt - start;
1788
1789 /* Process flags */
1790 spec->flags = 0;
1791
1792 while (1) { /* this also skips first '%' */
1793 bool found = true;
1794
1795 ++fmt;
1796
1797 switch (*fmt) {
1798 case '-': spec->flags |= LEFT; break;
1799 case '+': spec->flags |= PLUS; break;
1800 case ' ': spec->flags |= SPACE; break;
1801 case '#': spec->flags |= SPECIAL; break;
1802 case '0': spec->flags |= ZEROPAD; break;
1803 default: found = false;
1804 }
1805
1806 if (!found)
1807 break;
1808 }
1809
1810 /* get field width */
1811 spec->field_width = -1;
1812
1813 if (isdigit(*fmt))
1814 spec->field_width = skip_atoi(&fmt);
1815 else if (*fmt == '*') {
1816 /* it's the next argument */
1817 spec->type = FORMAT_TYPE_WIDTH;
1818 return ++fmt - start;
1819 }
1820
1821precision:
1822 /* get the precision */
1823 spec->precision = -1;
1824 if (*fmt == '.') {
1825 ++fmt;
1826 if (isdigit(*fmt)) {
1827 spec->precision = skip_atoi(&fmt);
1828 if (spec->precision < 0)
1829 spec->precision = 0;
1830 } else if (*fmt == '*') {
1831 /* it's the next argument */
1832 spec->type = FORMAT_TYPE_PRECISION;
1833 return ++fmt - start;
1834 }
1835 }
1836
1837qualifier:
1838 /* get the conversion qualifier */
1839 qualifier = 0;
1840 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1841 _tolower(*fmt) == 'z' || *fmt == 't') {
1842 qualifier = *fmt++;
1843 if (unlikely(qualifier == *fmt)) {
1844 if (qualifier == 'l') {
1845 qualifier = 'L';
1846 ++fmt;
1847 } else if (qualifier == 'h') {
1848 qualifier = 'H';
1849 ++fmt;
1850 }
1851 }
1852 }
1853
1854 /* default base */
1855 spec->base = 10;
1856 switch (*fmt) {
1857 case 'c':
1858 spec->type = FORMAT_TYPE_CHAR;
1859 return ++fmt - start;
1860
1861 case 's':
1862 spec->type = FORMAT_TYPE_STR;
1863 return ++fmt - start;
1864
1865 case 'p':
1866 spec->type = FORMAT_TYPE_PTR;
1867 return ++fmt - start;
1868
1869 case '%':
1870 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1871 return ++fmt - start;
1872
1873 /* integer number formats - set up the flags and "break" */
1874 case 'o':
1875 spec->base = 8;
1876 break;
1877
1878 case 'x':
1879 spec->flags |= SMALL;
1880
1881 case 'X':
1882 spec->base = 16;
1883 break;
1884
1885 case 'd':
1886 case 'i':
1887 spec->flags |= SIGN;
1888 case 'u':
1889 break;
1890
1891 case 'n':
1892 /*
1893 * Since %n poses a greater security risk than
1894 * utility, treat it as any other invalid or
1895 * unsupported format specifier.
1896 */
1897 /* Fall-through */
1898
1899 default:
1900 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
1901 spec->type = FORMAT_TYPE_INVALID;
1902 return fmt - start;
1903 }
1904
1905 if (qualifier == 'L')
1906 spec->type = FORMAT_TYPE_LONG_LONG;
1907 else if (qualifier == 'l') {
1908 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1909 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1910 } else if (_tolower(qualifier) == 'z') {
1911 spec->type = FORMAT_TYPE_SIZE_T;
1912 } else if (qualifier == 't') {
1913 spec->type = FORMAT_TYPE_PTRDIFF;
1914 } else if (qualifier == 'H') {
1915 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1916 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1917 } else if (qualifier == 'h') {
1918 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1919 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1920 } else {
1921 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1922 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1923 }
1924
1925 return ++fmt - start;
1926}
1927
1928static void
1929set_field_width(struct printf_spec *spec, int width)
1930{
1931 spec->field_width = width;
1932 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
1933 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
1934 }
1935}
1936
1937static void
1938set_precision(struct printf_spec *spec, int prec)
1939{
1940 spec->precision = prec;
1941 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
1942 spec->precision = clamp(prec, 0, PRECISION_MAX);
1943 }
1944}
1945
1946/**
1947 * vsnprintf - Format a string and place it in a buffer
1948 * @buf: The buffer to place the result into
1949 * @size: The size of the buffer, including the trailing null space
1950 * @fmt: The format string to use
1951 * @args: Arguments for the format string
1952 *
1953 * This function generally follows C99 vsnprintf, but has some
1954 * extensions and a few limitations:
1955 *
1956 * %n is unsupported
1957 * %p* is handled by pointer()
1958 *
1959 * See pointer() or Documentation/printk-formats.txt for more
1960 * extensive description.
1961 *
1962 * ** Please update the documentation in both places when making changes **
1963 *
1964 * The return value is the number of characters which would
1965 * be generated for the given input, excluding the trailing
1966 * '\0', as per ISO C99. If you want to have the exact
1967 * number of characters written into @buf as return value
1968 * (not including the trailing '\0'), use vscnprintf(). If the
1969 * return is greater than or equal to @size, the resulting
1970 * string is truncated.
1971 *
1972 * If you're not already dealing with a va_list consider using snprintf().
1973 */
1974int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1975{
1976 unsigned long long num;
1977 char *str, *end;
1978 struct printf_spec spec = {0};
1979
1980 /* Reject out-of-range values early. Large positive sizes are
1981 used for unknown buffer sizes. */
1982 if (WARN_ON_ONCE(size > INT_MAX))
1983 return 0;
1984
1985 str = buf;
1986 end = buf + size;
1987
1988 /* Make sure end is always >= buf */
1989 if (end < buf) {
1990 end = ((void *)-1);
1991 size = end - buf;
1992 }
1993
1994 while (*fmt) {
1995 const char *old_fmt = fmt;
1996 int read = format_decode(fmt, &spec);
1997
1998 fmt += read;
1999
2000 switch (spec.type) {
2001 case FORMAT_TYPE_NONE: {
2002 int copy = read;
2003 if (str < end) {
2004 if (copy > end - str)
2005 copy = end - str;
2006 memcpy(str, old_fmt, copy);
2007 }
2008 str += read;
2009 break;
2010 }
2011
2012 case FORMAT_TYPE_WIDTH:
2013 set_field_width(&spec, va_arg(args, int));
2014 break;
2015
2016 case FORMAT_TYPE_PRECISION:
2017 set_precision(&spec, va_arg(args, int));
2018 break;
2019
2020 case FORMAT_TYPE_CHAR: {
2021 char c;
2022
2023 if (!(spec.flags & LEFT)) {
2024 while (--spec.field_width > 0) {
2025 if (str < end)
2026 *str = ' ';
2027 ++str;
2028
2029 }
2030 }
2031 c = (unsigned char) va_arg(args, int);
2032 if (str < end)
2033 *str = c;
2034 ++str;
2035 while (--spec.field_width > 0) {
2036 if (str < end)
2037 *str = ' ';
2038 ++str;
2039 }
2040 break;
2041 }
2042
2043 case FORMAT_TYPE_STR:
2044 str = string(str, end, va_arg(args, char *), spec);
2045 break;
2046
2047 case FORMAT_TYPE_PTR:
2048 str = pointer(fmt, str, end, va_arg(args, void *),
2049 spec);
2050 while (isalnum(*fmt))
2051 fmt++;
2052 break;
2053
2054 case FORMAT_TYPE_PERCENT_CHAR:
2055 if (str < end)
2056 *str = '%';
2057 ++str;
2058 break;
2059
2060 case FORMAT_TYPE_INVALID:
2061 /*
2062 * Presumably the arguments passed gcc's type
2063 * checking, but there is no safe or sane way
2064 * for us to continue parsing the format and
2065 * fetching from the va_list; the remaining
2066 * specifiers and arguments would be out of
2067 * sync.
2068 */
2069 goto out;
2070
2071 default:
2072 switch (spec.type) {
2073 case FORMAT_TYPE_LONG_LONG:
2074 num = va_arg(args, long long);
2075 break;
2076 case FORMAT_TYPE_ULONG:
2077 num = va_arg(args, unsigned long);
2078 break;
2079 case FORMAT_TYPE_LONG:
2080 num = va_arg(args, long);
2081 break;
2082 case FORMAT_TYPE_SIZE_T:
2083 if (spec.flags & SIGN)
2084 num = va_arg(args, ssize_t);
2085 else
2086 num = va_arg(args, size_t);
2087 break;
2088 case FORMAT_TYPE_PTRDIFF:
2089 num = va_arg(args, ptrdiff_t);
2090 break;
2091 case FORMAT_TYPE_UBYTE:
2092 num = (unsigned char) va_arg(args, int);
2093 break;
2094 case FORMAT_TYPE_BYTE:
2095 num = (signed char) va_arg(args, int);
2096 break;
2097 case FORMAT_TYPE_USHORT:
2098 num = (unsigned short) va_arg(args, int);
2099 break;
2100 case FORMAT_TYPE_SHORT:
2101 num = (short) va_arg(args, int);
2102 break;
2103 case FORMAT_TYPE_INT:
2104 num = (int) va_arg(args, int);
2105 break;
2106 default:
2107 num = va_arg(args, unsigned int);
2108 }
2109
2110 str = number(str, end, num, spec);
2111 }
2112 }
2113
2114out:
2115 if (size > 0) {
2116 if (str < end)
2117 *str = '\0';
2118 else
2119 end[-1] = '\0';
2120 }
2121
2122 /* the trailing null byte doesn't count towards the total */
2123 return str-buf;
2124
2125}
2126EXPORT_SYMBOL(vsnprintf);
2127
2128/**
2129 * vscnprintf - Format a string and place it in a buffer
2130 * @buf: The buffer to place the result into
2131 * @size: The size of the buffer, including the trailing null space
2132 * @fmt: The format string to use
2133 * @args: Arguments for the format string
2134 *
2135 * The return value is the number of characters which have been written into
2136 * the @buf not including the trailing '\0'. If @size is == 0 the function
2137 * returns 0.
2138 *
2139 * If you're not already dealing with a va_list consider using scnprintf().
2140 *
2141 * See the vsnprintf() documentation for format string extensions over C99.
2142 */
2143int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2144{
2145 int i;
2146
2147 i = vsnprintf(buf, size, fmt, args);
2148
2149 if (likely(i < size))
2150 return i;
2151 if (size != 0)
2152 return size - 1;
2153 return 0;
2154}
2155EXPORT_SYMBOL(vscnprintf);
2156
2157/**
2158 * snprintf - Format a string and place it in a buffer
2159 * @buf: The buffer to place the result into
2160 * @size: The size of the buffer, including the trailing null space
2161 * @fmt: The format string to use
2162 * @...: Arguments for the format string
2163 *
2164 * The return value is the number of characters which would be
2165 * generated for the given input, excluding the trailing null,
2166 * as per ISO C99. If the return is greater than or equal to
2167 * @size, the resulting string is truncated.
2168 *
2169 * See the vsnprintf() documentation for format string extensions over C99.
2170 */
2171int snprintf(char *buf, size_t size, const char *fmt, ...)
2172{
2173 va_list args;
2174 int i;
2175
2176 va_start(args, fmt);
2177 i = vsnprintf(buf, size, fmt, args);
2178 va_end(args);
2179
2180 return i;
2181}
2182EXPORT_SYMBOL(snprintf);
2183
2184/**
2185 * scnprintf - Format a string and place it in a buffer
2186 * @buf: The buffer to place the result into
2187 * @size: The size of the buffer, including the trailing null space
2188 * @fmt: The format string to use
2189 * @...: Arguments for the format string
2190 *
2191 * The return value is the number of characters written into @buf not including
2192 * the trailing '\0'. If @size is == 0 the function returns 0.
2193 */
2194
2195int scnprintf(char *buf, size_t size, const char *fmt, ...)
2196{
2197 va_list args;
2198 int i;
2199
2200 va_start(args, fmt);
2201 i = vscnprintf(buf, size, fmt, args);
2202 va_end(args);
2203
2204 return i;
2205}
2206EXPORT_SYMBOL(scnprintf);
2207
2208/**
2209 * vsprintf - Format a string and place it in a buffer
2210 * @buf: The buffer to place the result into
2211 * @fmt: The format string to use
2212 * @args: Arguments for the format string
2213 *
2214 * The function returns the number of characters written
2215 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2216 * buffer overflows.
2217 *
2218 * If you're not already dealing with a va_list consider using sprintf().
2219 *
2220 * See the vsnprintf() documentation for format string extensions over C99.
2221 */
2222int vsprintf(char *buf, const char *fmt, va_list args)
2223{
2224 return vsnprintf(buf, INT_MAX, fmt, args);
2225}
2226EXPORT_SYMBOL(vsprintf);
2227
2228/**
2229 * sprintf - Format a string and place it in a buffer
2230 * @buf: The buffer to place the result into
2231 * @fmt: The format string to use
2232 * @...: Arguments for the format string
2233 *
2234 * The function returns the number of characters written
2235 * into @buf. Use snprintf() or scnprintf() in order to avoid
2236 * buffer overflows.
2237 *
2238 * See the vsnprintf() documentation for format string extensions over C99.
2239 */
2240int sprintf(char *buf, const char *fmt, ...)
2241{
2242 va_list args;
2243 int i;
2244
2245 va_start(args, fmt);
2246 i = vsnprintf(buf, INT_MAX, fmt, args);
2247 va_end(args);
2248
2249 return i;
2250}
2251EXPORT_SYMBOL(sprintf);
2252
2253#ifdef CONFIG_BINARY_PRINTF
2254/*
2255 * bprintf service:
2256 * vbin_printf() - VA arguments to binary data
2257 * bstr_printf() - Binary data to text string
2258 */
2259
2260/**
2261 * vbin_printf - Parse a format string and place args' binary value in a buffer
2262 * @bin_buf: The buffer to place args' binary value
2263 * @size: The size of the buffer(by words(32bits), not characters)
2264 * @fmt: The format string to use
2265 * @args: Arguments for the format string
2266 *
2267 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2268 * is skipped.
2269 *
2270 * The return value is the number of words(32bits) which would be generated for
2271 * the given input.
2272 *
2273 * NOTE:
2274 * If the return value is greater than @size, the resulting bin_buf is NOT
2275 * valid for bstr_printf().
2276 */
2277int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2278{
2279 struct printf_spec spec = {0};
2280 char *str, *end;
2281
2282 str = (char *)bin_buf;
2283 end = (char *)(bin_buf + size);
2284
2285#define save_arg(type) \
2286do { \
2287 if (sizeof(type) == 8) { \
2288 unsigned long long value; \
2289 str = PTR_ALIGN(str, sizeof(u32)); \
2290 value = va_arg(args, unsigned long long); \
2291 if (str + sizeof(type) <= end) { \
2292 *(u32 *)str = *(u32 *)&value; \
2293 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2294 } \
2295 } else { \
2296 unsigned long value; \
2297 str = PTR_ALIGN(str, sizeof(type)); \
2298 value = va_arg(args, int); \
2299 if (str + sizeof(type) <= end) \
2300 *(typeof(type) *)str = (type)value; \
2301 } \
2302 str += sizeof(type); \
2303} while (0)
2304
2305 while (*fmt) {
2306 int read = format_decode(fmt, &spec);
2307
2308 fmt += read;
2309
2310 switch (spec.type) {
2311 case FORMAT_TYPE_NONE:
2312 case FORMAT_TYPE_PERCENT_CHAR:
2313 break;
2314 case FORMAT_TYPE_INVALID:
2315 goto out;
2316
2317 case FORMAT_TYPE_WIDTH:
2318 case FORMAT_TYPE_PRECISION:
2319 save_arg(int);
2320 break;
2321
2322 case FORMAT_TYPE_CHAR:
2323 save_arg(char);
2324 break;
2325
2326 case FORMAT_TYPE_STR: {
2327 const char *save_str = va_arg(args, char *);
2328 size_t len;
2329
2330 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2331 || (unsigned long)save_str < PAGE_SIZE)
2332 save_str = "(null)";
2333 len = strlen(save_str) + 1;
2334 if (str + len < end)
2335 memcpy(str, save_str, len);
2336 str += len;
2337 break;
2338 }
2339
2340 case FORMAT_TYPE_PTR:
2341 save_arg(void *);
2342 /* skip all alphanumeric pointer suffixes */
2343 while (isalnum(*fmt))
2344 fmt++;
2345 break;
2346
2347 default:
2348 switch (spec.type) {
2349
2350 case FORMAT_TYPE_LONG_LONG:
2351 save_arg(long long);
2352 break;
2353 case FORMAT_TYPE_ULONG:
2354 case FORMAT_TYPE_LONG:
2355 save_arg(unsigned long);
2356 break;
2357 case FORMAT_TYPE_SIZE_T:
2358 save_arg(size_t);
2359 break;
2360 case FORMAT_TYPE_PTRDIFF:
2361 save_arg(ptrdiff_t);
2362 break;
2363 case FORMAT_TYPE_UBYTE:
2364 case FORMAT_TYPE_BYTE:
2365 save_arg(char);
2366 break;
2367 case FORMAT_TYPE_USHORT:
2368 case FORMAT_TYPE_SHORT:
2369 save_arg(short);
2370 break;
2371 default:
2372 save_arg(int);
2373 }
2374 }
2375 }
2376
2377out:
2378 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2379#undef save_arg
2380}
2381EXPORT_SYMBOL_GPL(vbin_printf);
2382
2383/**
2384 * bstr_printf - Format a string from binary arguments and place it in a buffer
2385 * @buf: The buffer to place the result into
2386 * @size: The size of the buffer, including the trailing null space
2387 * @fmt: The format string to use
2388 * @bin_buf: Binary arguments for the format string
2389 *
2390 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2391 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2392 * a binary buffer that generated by vbin_printf.
2393 *
2394 * The format follows C99 vsnprintf, but has some extensions:
2395 * see vsnprintf comment for details.
2396 *
2397 * The return value is the number of characters which would
2398 * be generated for the given input, excluding the trailing
2399 * '\0', as per ISO C99. If you want to have the exact
2400 * number of characters written into @buf as return value
2401 * (not including the trailing '\0'), use vscnprintf(). If the
2402 * return is greater than or equal to @size, the resulting
2403 * string is truncated.
2404 */
2405int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2406{
2407 struct printf_spec spec = {0};
2408 char *str, *end;
2409 const char *args = (const char *)bin_buf;
2410
2411 if (WARN_ON_ONCE(size > INT_MAX))
2412 return 0;
2413
2414 str = buf;
2415 end = buf + size;
2416
2417#define get_arg(type) \
2418({ \
2419 typeof(type) value; \
2420 if (sizeof(type) == 8) { \
2421 args = PTR_ALIGN(args, sizeof(u32)); \
2422 *(u32 *)&value = *(u32 *)args; \
2423 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2424 } else { \
2425 args = PTR_ALIGN(args, sizeof(type)); \
2426 value = *(typeof(type) *)args; \
2427 } \
2428 args += sizeof(type); \
2429 value; \
2430})
2431
2432 /* Make sure end is always >= buf */
2433 if (end < buf) {
2434 end = ((void *)-1);
2435 size = end - buf;
2436 }
2437
2438 while (*fmt) {
2439 const char *old_fmt = fmt;
2440 int read = format_decode(fmt, &spec);
2441
2442 fmt += read;
2443
2444 switch (spec.type) {
2445 case FORMAT_TYPE_NONE: {
2446 int copy = read;
2447 if (str < end) {
2448 if (copy > end - str)
2449 copy = end - str;
2450 memcpy(str, old_fmt, copy);
2451 }
2452 str += read;
2453 break;
2454 }
2455
2456 case FORMAT_TYPE_WIDTH:
2457 set_field_width(&spec, get_arg(int));
2458 break;
2459
2460 case FORMAT_TYPE_PRECISION:
2461 set_precision(&spec, get_arg(int));
2462 break;
2463
2464 case FORMAT_TYPE_CHAR: {
2465 char c;
2466
2467 if (!(spec.flags & LEFT)) {
2468 while (--spec.field_width > 0) {
2469 if (str < end)
2470 *str = ' ';
2471 ++str;
2472 }
2473 }
2474 c = (unsigned char) get_arg(char);
2475 if (str < end)
2476 *str = c;
2477 ++str;
2478 while (--spec.field_width > 0) {
2479 if (str < end)
2480 *str = ' ';
2481 ++str;
2482 }
2483 break;
2484 }
2485
2486 case FORMAT_TYPE_STR: {
2487 const char *str_arg = args;
2488 args += strlen(str_arg) + 1;
2489 str = string(str, end, (char *)str_arg, spec);
2490 break;
2491 }
2492
2493 case FORMAT_TYPE_PTR:
2494 str = pointer(fmt, str, end, get_arg(void *), spec);
2495 while (isalnum(*fmt))
2496 fmt++;
2497 break;
2498
2499 case FORMAT_TYPE_PERCENT_CHAR:
2500 if (str < end)
2501 *str = '%';
2502 ++str;
2503 break;
2504
2505 case FORMAT_TYPE_INVALID:
2506 goto out;
2507
2508 default: {
2509 unsigned long long num;
2510
2511 switch (spec.type) {
2512
2513 case FORMAT_TYPE_LONG_LONG:
2514 num = get_arg(long long);
2515 break;
2516 case FORMAT_TYPE_ULONG:
2517 case FORMAT_TYPE_LONG:
2518 num = get_arg(unsigned long);
2519 break;
2520 case FORMAT_TYPE_SIZE_T:
2521 num = get_arg(size_t);
2522 break;
2523 case FORMAT_TYPE_PTRDIFF:
2524 num = get_arg(ptrdiff_t);
2525 break;
2526 case FORMAT_TYPE_UBYTE:
2527 num = get_arg(unsigned char);
2528 break;
2529 case FORMAT_TYPE_BYTE:
2530 num = get_arg(signed char);
2531 break;
2532 case FORMAT_TYPE_USHORT:
2533 num = get_arg(unsigned short);
2534 break;
2535 case FORMAT_TYPE_SHORT:
2536 num = get_arg(short);
2537 break;
2538 case FORMAT_TYPE_UINT:
2539 num = get_arg(unsigned int);
2540 break;
2541 default:
2542 num = get_arg(int);
2543 }
2544
2545 str = number(str, end, num, spec);
2546 } /* default: */
2547 } /* switch(spec.type) */
2548 } /* while(*fmt) */
2549
2550out:
2551 if (size > 0) {
2552 if (str < end)
2553 *str = '\0';
2554 else
2555 end[-1] = '\0';
2556 }
2557
2558#undef get_arg
2559
2560 /* the trailing null byte doesn't count towards the total */
2561 return str - buf;
2562}
2563EXPORT_SYMBOL_GPL(bstr_printf);
2564
2565/**
2566 * bprintf - Parse a format string and place args' binary value in a buffer
2567 * @bin_buf: The buffer to place args' binary value
2568 * @size: The size of the buffer(by words(32bits), not characters)
2569 * @fmt: The format string to use
2570 * @...: Arguments for the format string
2571 *
2572 * The function returns the number of words(u32) written
2573 * into @bin_buf.
2574 */
2575int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2576{
2577 va_list args;
2578 int ret;
2579
2580 va_start(args, fmt);
2581 ret = vbin_printf(bin_buf, size, fmt, args);
2582 va_end(args);
2583
2584 return ret;
2585}
2586EXPORT_SYMBOL_GPL(bprintf);
2587
2588#endif /* CONFIG_BINARY_PRINTF */
2589
2590/**
2591 * vsscanf - Unformat a buffer into a list of arguments
2592 * @buf: input buffer
2593 * @fmt: format of buffer
2594 * @args: arguments
2595 */
2596int vsscanf(const char *buf, const char *fmt, va_list args)
2597{
2598 const char *str = buf;
2599 char *next;
2600 char digit;
2601 int num = 0;
2602 u8 qualifier;
2603 unsigned int base;
2604 union {
2605 long long s;
2606 unsigned long long u;
2607 } val;
2608 s16 field_width;
2609 bool is_sign;
2610
2611 while (*fmt) {
2612 /* skip any white space in format */
2613 /* white space in format matchs any amount of
2614 * white space, including none, in the input.
2615 */
2616 if (isspace(*fmt)) {
2617 fmt = skip_spaces(++fmt);
2618 str = skip_spaces(str);
2619 }
2620
2621 /* anything that is not a conversion must match exactly */
2622 if (*fmt != '%' && *fmt) {
2623 if (*fmt++ != *str++)
2624 break;
2625 continue;
2626 }
2627
2628 if (!*fmt)
2629 break;
2630 ++fmt;
2631
2632 /* skip this conversion.
2633 * advance both strings to next white space
2634 */
2635 if (*fmt == '*') {
2636 if (!*str)
2637 break;
2638 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2639 /* '%*[' not yet supported, invalid format */
2640 if (*fmt == '[')
2641 return num;
2642 fmt++;
2643 }
2644 while (!isspace(*str) && *str)
2645 str++;
2646 continue;
2647 }
2648
2649 /* get field width */
2650 field_width = -1;
2651 if (isdigit(*fmt)) {
2652 field_width = skip_atoi(&fmt);
2653 if (field_width <= 0)
2654 break;
2655 }
2656
2657 /* get conversion qualifier */
2658 qualifier = -1;
2659 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2660 _tolower(*fmt) == 'z') {
2661 qualifier = *fmt++;
2662 if (unlikely(qualifier == *fmt)) {
2663 if (qualifier == 'h') {
2664 qualifier = 'H';
2665 fmt++;
2666 } else if (qualifier == 'l') {
2667 qualifier = 'L';
2668 fmt++;
2669 }
2670 }
2671 }
2672
2673 if (!*fmt)
2674 break;
2675
2676 if (*fmt == 'n') {
2677 /* return number of characters read so far */
2678 *va_arg(args, int *) = str - buf;
2679 ++fmt;
2680 continue;
2681 }
2682
2683 if (!*str)
2684 break;
2685
2686 base = 10;
2687 is_sign = false;
2688
2689 switch (*fmt++) {
2690 case 'c':
2691 {
2692 char *s = (char *)va_arg(args, char*);
2693 if (field_width == -1)
2694 field_width = 1;
2695 do {
2696 *s++ = *str++;
2697 } while (--field_width > 0 && *str);
2698 num++;
2699 }
2700 continue;
2701 case 's':
2702 {
2703 char *s = (char *)va_arg(args, char *);
2704 if (field_width == -1)
2705 field_width = SHRT_MAX;
2706 /* first, skip leading white space in buffer */
2707 str = skip_spaces(str);
2708
2709 /* now copy until next white space */
2710 while (*str && !isspace(*str) && field_width--)
2711 *s++ = *str++;
2712 *s = '\0';
2713 num++;
2714 }
2715 continue;
2716 /*
2717 * Warning: This implementation of the '[' conversion specifier
2718 * deviates from its glibc counterpart in the following ways:
2719 * (1) It does NOT support ranges i.e. '-' is NOT a special
2720 * character
2721 * (2) It cannot match the closing bracket ']' itself
2722 * (3) A field width is required
2723 * (4) '%*[' (discard matching input) is currently not supported
2724 *
2725 * Example usage:
2726 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2727 * buf1, buf2, buf3);
2728 * if (ret < 3)
2729 * // etc..
2730 */
2731 case '[':
2732 {
2733 char *s = (char *)va_arg(args, char *);
2734 DECLARE_BITMAP(set, 256) = {0};
2735 unsigned int len = 0;
2736 bool negate = (*fmt == '^');
2737
2738 /* field width is required */
2739 if (field_width == -1)
2740 return num;
2741
2742 if (negate)
2743 ++fmt;
2744
2745 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2746 set_bit((u8)*fmt, set);
2747
2748 /* no ']' or no character set found */
2749 if (!*fmt || !len)
2750 return num;
2751 ++fmt;
2752
2753 if (negate) {
2754 bitmap_complement(set, set, 256);
2755 /* exclude null '\0' byte */
2756 clear_bit(0, set);
2757 }
2758
2759 /* match must be non-empty */
2760 if (!test_bit((u8)*str, set))
2761 return num;
2762
2763 while (test_bit((u8)*str, set) && field_width--)
2764 *s++ = *str++;
2765 *s = '\0';
2766 ++num;
2767 }
2768 continue;
2769 case 'o':
2770 base = 8;
2771 break;
2772 case 'x':
2773 case 'X':
2774 base = 16;
2775 break;
2776 case 'i':
2777 base = 0;
2778 case 'd':
2779 is_sign = true;
2780 case 'u':
2781 break;
2782 case '%':
2783 /* looking for '%' in str */
2784 if (*str++ != '%')
2785 return num;
2786 continue;
2787 default:
2788 /* invalid format; stop here */
2789 return num;
2790 }
2791
2792 /* have some sort of integer conversion.
2793 * first, skip white space in buffer.
2794 */
2795 str = skip_spaces(str);
2796
2797 digit = *str;
2798 if (is_sign && digit == '-')
2799 digit = *(str + 1);
2800
2801 if (!digit
2802 || (base == 16 && !isxdigit(digit))
2803 || (base == 10 && !isdigit(digit))
2804 || (base == 8 && (!isdigit(digit) || digit > '7'))
2805 || (base == 0 && !isdigit(digit)))
2806 break;
2807
2808 if (is_sign)
2809 val.s = qualifier != 'L' ?
2810 simple_strtol(str, &next, base) :
2811 simple_strtoll(str, &next, base);
2812 else
2813 val.u = qualifier != 'L' ?
2814 simple_strtoul(str, &next, base) :
2815 simple_strtoull(str, &next, base);
2816
2817 if (field_width > 0 && next - str > field_width) {
2818 if (base == 0)
2819 _parse_integer_fixup_radix(str, &base);
2820 while (next - str > field_width) {
2821 if (is_sign)
2822 val.s = div_s64(val.s, base);
2823 else
2824 val.u = div_u64(val.u, base);
2825 --next;
2826 }
2827 }
2828
2829 switch (qualifier) {
2830 case 'H': /* that's 'hh' in format */
2831 if (is_sign)
2832 *va_arg(args, signed char *) = val.s;
2833 else
2834 *va_arg(args, unsigned char *) = val.u;
2835 break;
2836 case 'h':
2837 if (is_sign)
2838 *va_arg(args, short *) = val.s;
2839 else
2840 *va_arg(args, unsigned short *) = val.u;
2841 break;
2842 case 'l':
2843 if (is_sign)
2844 *va_arg(args, long *) = val.s;
2845 else
2846 *va_arg(args, unsigned long *) = val.u;
2847 break;
2848 case 'L':
2849 if (is_sign)
2850 *va_arg(args, long long *) = val.s;
2851 else
2852 *va_arg(args, unsigned long long *) = val.u;
2853 break;
2854 case 'Z':
2855 case 'z':
2856 *va_arg(args, size_t *) = val.u;
2857 break;
2858 default:
2859 if (is_sign)
2860 *va_arg(args, int *) = val.s;
2861 else
2862 *va_arg(args, unsigned int *) = val.u;
2863 break;
2864 }
2865 num++;
2866
2867 if (!next)
2868 break;
2869 str = next;
2870 }
2871
2872 return num;
2873}
2874EXPORT_SYMBOL(vsscanf);
2875
2876/**
2877 * sscanf - Unformat a buffer into a list of arguments
2878 * @buf: input buffer
2879 * @fmt: formatting of buffer
2880 * @...: resulting arguments
2881 */
2882int sscanf(const char *buf, const char *fmt, ...)
2883{
2884 va_list args;
2885 int i;
2886
2887 va_start(args, fmt);
2888 i = vsscanf(buf, fmt, args);
2889 va_end(args);
2890
2891 return i;
2892}
2893EXPORT_SYMBOL(sscanf);
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
34static unsigned int simple_guess_base(const char *cp)
35{
36 if (cp[0] == '0') {
37 if (_tolower(cp[1]) == 'x' && isxdigit(cp[2]))
38 return 16;
39 else
40 return 8;
41 } else {
42 return 10;
43 }
44}
45
46/**
47 * simple_strtoull - convert a string to an unsigned long long
48 * @cp: The start of the string
49 * @endp: A pointer to the end of the parsed string will be placed here
50 * @base: The number base to use
51 */
52unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
53{
54 unsigned long long result = 0;
55
56 if (!base)
57 base = simple_guess_base(cp);
58
59 if (base == 16 && cp[0] == '0' && _tolower(cp[1]) == 'x')
60 cp += 2;
61
62 while (isxdigit(*cp)) {
63 unsigned int value;
64
65 value = isdigit(*cp) ? *cp - '0' : _tolower(*cp) - 'a' + 10;
66 if (value >= base)
67 break;
68 result = result * base + value;
69 cp++;
70 }
71 if (endp)
72 *endp = (char *)cp;
73
74 return result;
75}
76EXPORT_SYMBOL(simple_strtoull);
77
78/**
79 * simple_strtoul - convert a string to an unsigned long
80 * @cp: The start of the string
81 * @endp: A pointer to the end of the parsed string will be placed here
82 * @base: The number base to use
83 */
84unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
85{
86 return simple_strtoull(cp, endp, base);
87}
88EXPORT_SYMBOL(simple_strtoul);
89
90/**
91 * simple_strtol - convert a string to a signed long
92 * @cp: The start of the string
93 * @endp: A pointer to the end of the parsed string will be placed here
94 * @base: The number base to use
95 */
96long simple_strtol(const char *cp, char **endp, unsigned int base)
97{
98 if (*cp == '-')
99 return -simple_strtoul(cp + 1, endp, base);
100
101 return simple_strtoul(cp, endp, base);
102}
103EXPORT_SYMBOL(simple_strtol);
104
105/**
106 * simple_strtoll - convert a string to a signed long long
107 * @cp: The start of the string
108 * @endp: A pointer to the end of the parsed string will be placed here
109 * @base: The number base to use
110 */
111long long simple_strtoll(const char *cp, char **endp, unsigned int base)
112{
113 if (*cp == '-')
114 return -simple_strtoull(cp + 1, endp, base);
115
116 return simple_strtoull(cp, endp, base);
117}
118EXPORT_SYMBOL(simple_strtoll);
119
120static noinline_for_stack
121int skip_atoi(const char **s)
122{
123 int i = 0;
124
125 while (isdigit(**s))
126 i = i*10 + *((*s)++) - '0';
127
128 return i;
129}
130
131/* Decimal conversion is by far the most typical, and is used
132 * for /proc and /sys data. This directly impacts e.g. top performance
133 * with many processes running. We optimize it for speed
134 * using code from
135 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
136 * (with permission from the author, Douglas W. Jones). */
137
138/* Formats correctly any integer in [0,99999].
139 * Outputs from one to five digits depending on input.
140 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
141static noinline_for_stack
142char *put_dec_trunc(char *buf, unsigned q)
143{
144 unsigned d3, d2, d1, d0;
145 d1 = (q>>4) & 0xf;
146 d2 = (q>>8) & 0xf;
147 d3 = (q>>12);
148
149 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
150 q = (d0 * 0xcd) >> 11;
151 d0 = d0 - 10*q;
152 *buf++ = d0 + '0'; /* least significant digit */
153 d1 = q + 9*d3 + 5*d2 + d1;
154 if (d1 != 0) {
155 q = (d1 * 0xcd) >> 11;
156 d1 = d1 - 10*q;
157 *buf++ = d1 + '0'; /* next digit */
158
159 d2 = q + 2*d2;
160 if ((d2 != 0) || (d3 != 0)) {
161 q = (d2 * 0xd) >> 7;
162 d2 = d2 - 10*q;
163 *buf++ = d2 + '0'; /* next digit */
164
165 d3 = q + 4*d3;
166 if (d3 != 0) {
167 q = (d3 * 0xcd) >> 11;
168 d3 = d3 - 10*q;
169 *buf++ = d3 + '0'; /* next digit */
170 if (q != 0)
171 *buf++ = q + '0'; /* most sign. digit */
172 }
173 }
174 }
175
176 return buf;
177}
178/* Same with if's removed. Always emits five digits */
179static noinline_for_stack
180char *put_dec_full(char *buf, unsigned q)
181{
182 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
183 /* but anyway, gcc produces better code with full-sized ints */
184 unsigned d3, d2, d1, d0;
185 d1 = (q>>4) & 0xf;
186 d2 = (q>>8) & 0xf;
187 d3 = (q>>12);
188
189 /*
190 * Possible ways to approx. divide by 10
191 * gcc -O2 replaces multiply with shifts and adds
192 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
193 * (x * 0x67) >> 10: 1100111
194 * (x * 0x34) >> 9: 110100 - same
195 * (x * 0x1a) >> 8: 11010 - same
196 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
197 */
198 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
199 q = (d0 * 0xcd) >> 11;
200 d0 = d0 - 10*q;
201 *buf++ = d0 + '0';
202 d1 = q + 9*d3 + 5*d2 + d1;
203 q = (d1 * 0xcd) >> 11;
204 d1 = d1 - 10*q;
205 *buf++ = d1 + '0';
206
207 d2 = q + 2*d2;
208 q = (d2 * 0xd) >> 7;
209 d2 = d2 - 10*q;
210 *buf++ = d2 + '0';
211
212 d3 = q + 4*d3;
213 q = (d3 * 0xcd) >> 11; /* - shorter code */
214 /* q = (d3 * 0x67) >> 10; - would also work */
215 d3 = d3 - 10*q;
216 *buf++ = d3 + '0';
217 *buf++ = q + '0';
218
219 return buf;
220}
221/* No inlining helps gcc to use registers better */
222static noinline_for_stack
223char *put_dec(char *buf, unsigned long long num)
224{
225 while (1) {
226 unsigned rem;
227 if (num < 100000)
228 return put_dec_trunc(buf, num);
229 rem = do_div(num, 100000);
230 buf = put_dec_full(buf, rem);
231 }
232}
233
234#define ZEROPAD 1 /* pad with zero */
235#define SIGN 2 /* unsigned/signed long */
236#define PLUS 4 /* show plus */
237#define SPACE 8 /* space if plus */
238#define LEFT 16 /* left justified */
239#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
240#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
241
242enum format_type {
243 FORMAT_TYPE_NONE, /* Just a string part */
244 FORMAT_TYPE_WIDTH,
245 FORMAT_TYPE_PRECISION,
246 FORMAT_TYPE_CHAR,
247 FORMAT_TYPE_STR,
248 FORMAT_TYPE_PTR,
249 FORMAT_TYPE_PERCENT_CHAR,
250 FORMAT_TYPE_INVALID,
251 FORMAT_TYPE_LONG_LONG,
252 FORMAT_TYPE_ULONG,
253 FORMAT_TYPE_LONG,
254 FORMAT_TYPE_UBYTE,
255 FORMAT_TYPE_BYTE,
256 FORMAT_TYPE_USHORT,
257 FORMAT_TYPE_SHORT,
258 FORMAT_TYPE_UINT,
259 FORMAT_TYPE_INT,
260 FORMAT_TYPE_NRCHARS,
261 FORMAT_TYPE_SIZE_T,
262 FORMAT_TYPE_PTRDIFF
263};
264
265struct printf_spec {
266 u8 type; /* format_type enum */
267 u8 flags; /* flags to number() */
268 u8 base; /* number base, 8, 10 or 16 only */
269 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
270 s16 field_width; /* width of output field */
271 s16 precision; /* # of digits/chars */
272};
273
274static noinline_for_stack
275char *number(char *buf, char *end, unsigned long long num,
276 struct printf_spec spec)
277{
278 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
279 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
280
281 char tmp[66];
282 char sign;
283 char locase;
284 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
285 int i;
286
287 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
288 * produces same digits or (maybe lowercased) letters */
289 locase = (spec.flags & SMALL);
290 if (spec.flags & LEFT)
291 spec.flags &= ~ZEROPAD;
292 sign = 0;
293 if (spec.flags & SIGN) {
294 if ((signed long long)num < 0) {
295 sign = '-';
296 num = -(signed long long)num;
297 spec.field_width--;
298 } else if (spec.flags & PLUS) {
299 sign = '+';
300 spec.field_width--;
301 } else if (spec.flags & SPACE) {
302 sign = ' ';
303 spec.field_width--;
304 }
305 }
306 if (need_pfx) {
307 spec.field_width--;
308 if (spec.base == 16)
309 spec.field_width--;
310 }
311
312 /* generate full string in tmp[], in reverse order */
313 i = 0;
314 if (num == 0)
315 tmp[i++] = '0';
316 /* Generic code, for any base:
317 else do {
318 tmp[i++] = (digits[do_div(num,base)] | locase);
319 } while (num != 0);
320 */
321 else if (spec.base != 10) { /* 8 or 16 */
322 int mask = spec.base - 1;
323 int shift = 3;
324
325 if (spec.base == 16)
326 shift = 4;
327 do {
328 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
329 num >>= shift;
330 } while (num);
331 } else { /* base 10 */
332 i = put_dec(tmp, num) - tmp;
333 }
334
335 /* printing 100 using %2d gives "100", not "00" */
336 if (i > spec.precision)
337 spec.precision = i;
338 /* leading space padding */
339 spec.field_width -= spec.precision;
340 if (!(spec.flags & (ZEROPAD+LEFT))) {
341 while (--spec.field_width >= 0) {
342 if (buf < end)
343 *buf = ' ';
344 ++buf;
345 }
346 }
347 /* sign */
348 if (sign) {
349 if (buf < end)
350 *buf = sign;
351 ++buf;
352 }
353 /* "0x" / "0" prefix */
354 if (need_pfx) {
355 if (buf < end)
356 *buf = '0';
357 ++buf;
358 if (spec.base == 16) {
359 if (buf < end)
360 *buf = ('X' | locase);
361 ++buf;
362 }
363 }
364 /* zero or space padding */
365 if (!(spec.flags & LEFT)) {
366 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
367 while (--spec.field_width >= 0) {
368 if (buf < end)
369 *buf = c;
370 ++buf;
371 }
372 }
373 /* hmm even more zero padding? */
374 while (i <= --spec.precision) {
375 if (buf < end)
376 *buf = '0';
377 ++buf;
378 }
379 /* actual digits of result */
380 while (--i >= 0) {
381 if (buf < end)
382 *buf = tmp[i];
383 ++buf;
384 }
385 /* trailing space padding */
386 while (--spec.field_width >= 0) {
387 if (buf < end)
388 *buf = ' ';
389 ++buf;
390 }
391
392 return buf;
393}
394
395static noinline_for_stack
396char *string(char *buf, char *end, const char *s, struct printf_spec spec)
397{
398 int len, i;
399
400 if ((unsigned long)s < PAGE_SIZE)
401 s = "(null)";
402
403 len = strnlen(s, spec.precision);
404
405 if (!(spec.flags & LEFT)) {
406 while (len < spec.field_width--) {
407 if (buf < end)
408 *buf = ' ';
409 ++buf;
410 }
411 }
412 for (i = 0; i < len; ++i) {
413 if (buf < end)
414 *buf = *s;
415 ++buf; ++s;
416 }
417 while (len < spec.field_width--) {
418 if (buf < end)
419 *buf = ' ';
420 ++buf;
421 }
422
423 return buf;
424}
425
426static noinline_for_stack
427char *symbol_string(char *buf, char *end, void *ptr,
428 struct printf_spec spec, char ext)
429{
430 unsigned long value = (unsigned long) ptr;
431#ifdef CONFIG_KALLSYMS
432 char sym[KSYM_SYMBOL_LEN];
433 if (ext == 'B')
434 sprint_backtrace(sym, value);
435 else if (ext != 'f' && ext != 's')
436 sprint_symbol(sym, value);
437 else
438 kallsyms_lookup(value, NULL, NULL, NULL, sym);
439
440 return string(buf, end, sym, spec);
441#else
442 spec.field_width = 2 * sizeof(void *);
443 spec.flags |= SPECIAL | SMALL | ZEROPAD;
444 spec.base = 16;
445
446 return number(buf, end, value, spec);
447#endif
448}
449
450static noinline_for_stack
451char *resource_string(char *buf, char *end, struct resource *res,
452 struct printf_spec spec, const char *fmt)
453{
454#ifndef IO_RSRC_PRINTK_SIZE
455#define IO_RSRC_PRINTK_SIZE 6
456#endif
457
458#ifndef MEM_RSRC_PRINTK_SIZE
459#define MEM_RSRC_PRINTK_SIZE 10
460#endif
461 static const struct printf_spec io_spec = {
462 .base = 16,
463 .field_width = IO_RSRC_PRINTK_SIZE,
464 .precision = -1,
465 .flags = SPECIAL | SMALL | ZEROPAD,
466 };
467 static const struct printf_spec mem_spec = {
468 .base = 16,
469 .field_width = MEM_RSRC_PRINTK_SIZE,
470 .precision = -1,
471 .flags = SPECIAL | SMALL | ZEROPAD,
472 };
473 static const struct printf_spec bus_spec = {
474 .base = 16,
475 .field_width = 2,
476 .precision = -1,
477 .flags = SMALL | ZEROPAD,
478 };
479 static const struct printf_spec dec_spec = {
480 .base = 10,
481 .precision = -1,
482 .flags = 0,
483 };
484 static const struct printf_spec str_spec = {
485 .field_width = -1,
486 .precision = 10,
487 .flags = LEFT,
488 };
489 static const struct printf_spec flag_spec = {
490 .base = 16,
491 .precision = -1,
492 .flags = SPECIAL | SMALL,
493 };
494
495 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
496 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
497#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
498#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
499#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
500#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
501 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
502 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
503
504 char *p = sym, *pend = sym + sizeof(sym);
505 int decode = (fmt[0] == 'R') ? 1 : 0;
506 const struct printf_spec *specp;
507
508 *p++ = '[';
509 if (res->flags & IORESOURCE_IO) {
510 p = string(p, pend, "io ", str_spec);
511 specp = &io_spec;
512 } else if (res->flags & IORESOURCE_MEM) {
513 p = string(p, pend, "mem ", str_spec);
514 specp = &mem_spec;
515 } else if (res->flags & IORESOURCE_IRQ) {
516 p = string(p, pend, "irq ", str_spec);
517 specp = &dec_spec;
518 } else if (res->flags & IORESOURCE_DMA) {
519 p = string(p, pend, "dma ", str_spec);
520 specp = &dec_spec;
521 } else if (res->flags & IORESOURCE_BUS) {
522 p = string(p, pend, "bus ", str_spec);
523 specp = &bus_spec;
524 } else {
525 p = string(p, pend, "??? ", str_spec);
526 specp = &mem_spec;
527 decode = 0;
528 }
529 p = number(p, pend, res->start, *specp);
530 if (res->start != res->end) {
531 *p++ = '-';
532 p = number(p, pend, res->end, *specp);
533 }
534 if (decode) {
535 if (res->flags & IORESOURCE_MEM_64)
536 p = string(p, pend, " 64bit", str_spec);
537 if (res->flags & IORESOURCE_PREFETCH)
538 p = string(p, pend, " pref", str_spec);
539 if (res->flags & IORESOURCE_WINDOW)
540 p = string(p, pend, " window", str_spec);
541 if (res->flags & IORESOURCE_DISABLED)
542 p = string(p, pend, " disabled", str_spec);
543 } else {
544 p = string(p, pend, " flags ", str_spec);
545 p = number(p, pend, res->flags, flag_spec);
546 }
547 *p++ = ']';
548 *p = '\0';
549
550 return string(buf, end, sym, spec);
551}
552
553static noinline_for_stack
554char *mac_address_string(char *buf, char *end, u8 *addr,
555 struct printf_spec spec, const char *fmt)
556{
557 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
558 char *p = mac_addr;
559 int i;
560 char separator;
561
562 if (fmt[1] == 'F') { /* FDDI canonical format */
563 separator = '-';
564 } else {
565 separator = ':';
566 }
567
568 for (i = 0; i < 6; i++) {
569 p = pack_hex_byte(p, addr[i]);
570 if (fmt[0] == 'M' && i != 5)
571 *p++ = separator;
572 }
573 *p = '\0';
574
575 return string(buf, end, mac_addr, spec);
576}
577
578static noinline_for_stack
579char *ip4_string(char *p, const u8 *addr, const char *fmt)
580{
581 int i;
582 bool leading_zeros = (fmt[0] == 'i');
583 int index;
584 int step;
585
586 switch (fmt[2]) {
587 case 'h':
588#ifdef __BIG_ENDIAN
589 index = 0;
590 step = 1;
591#else
592 index = 3;
593 step = -1;
594#endif
595 break;
596 case 'l':
597 index = 3;
598 step = -1;
599 break;
600 case 'n':
601 case 'b':
602 default:
603 index = 0;
604 step = 1;
605 break;
606 }
607 for (i = 0; i < 4; i++) {
608 char temp[3]; /* hold each IP quad in reverse order */
609 int digits = put_dec_trunc(temp, addr[index]) - temp;
610 if (leading_zeros) {
611 if (digits < 3)
612 *p++ = '0';
613 if (digits < 2)
614 *p++ = '0';
615 }
616 /* reverse the digits in the quad */
617 while (digits--)
618 *p++ = temp[digits];
619 if (i < 3)
620 *p++ = '.';
621 index += step;
622 }
623 *p = '\0';
624
625 return p;
626}
627
628static noinline_for_stack
629char *ip6_compressed_string(char *p, const char *addr)
630{
631 int i, j, range;
632 unsigned char zerolength[8];
633 int longest = 1;
634 int colonpos = -1;
635 u16 word;
636 u8 hi, lo;
637 bool needcolon = false;
638 bool useIPv4;
639 struct in6_addr in6;
640
641 memcpy(&in6, addr, sizeof(struct in6_addr));
642
643 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
644
645 memset(zerolength, 0, sizeof(zerolength));
646
647 if (useIPv4)
648 range = 6;
649 else
650 range = 8;
651
652 /* find position of longest 0 run */
653 for (i = 0; i < range; i++) {
654 for (j = i; j < range; j++) {
655 if (in6.s6_addr16[j] != 0)
656 break;
657 zerolength[i]++;
658 }
659 }
660 for (i = 0; i < range; i++) {
661 if (zerolength[i] > longest) {
662 longest = zerolength[i];
663 colonpos = i;
664 }
665 }
666 if (longest == 1) /* don't compress a single 0 */
667 colonpos = -1;
668
669 /* emit address */
670 for (i = 0; i < range; i++) {
671 if (i == colonpos) {
672 if (needcolon || i == 0)
673 *p++ = ':';
674 *p++ = ':';
675 needcolon = false;
676 i += longest - 1;
677 continue;
678 }
679 if (needcolon) {
680 *p++ = ':';
681 needcolon = false;
682 }
683 /* hex u16 without leading 0s */
684 word = ntohs(in6.s6_addr16[i]);
685 hi = word >> 8;
686 lo = word & 0xff;
687 if (hi) {
688 if (hi > 0x0f)
689 p = pack_hex_byte(p, hi);
690 else
691 *p++ = hex_asc_lo(hi);
692 p = pack_hex_byte(p, lo);
693 }
694 else if (lo > 0x0f)
695 p = pack_hex_byte(p, lo);
696 else
697 *p++ = hex_asc_lo(lo);
698 needcolon = true;
699 }
700
701 if (useIPv4) {
702 if (needcolon)
703 *p++ = ':';
704 p = ip4_string(p, &in6.s6_addr[12], "I4");
705 }
706 *p = '\0';
707
708 return p;
709}
710
711static noinline_for_stack
712char *ip6_string(char *p, const char *addr, const char *fmt)
713{
714 int i;
715
716 for (i = 0; i < 8; i++) {
717 p = pack_hex_byte(p, *addr++);
718 p = pack_hex_byte(p, *addr++);
719 if (fmt[0] == 'I' && i != 7)
720 *p++ = ':';
721 }
722 *p = '\0';
723
724 return p;
725}
726
727static noinline_for_stack
728char *ip6_addr_string(char *buf, char *end, const u8 *addr,
729 struct printf_spec spec, const char *fmt)
730{
731 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
732
733 if (fmt[0] == 'I' && fmt[2] == 'c')
734 ip6_compressed_string(ip6_addr, addr);
735 else
736 ip6_string(ip6_addr, addr, fmt);
737
738 return string(buf, end, ip6_addr, spec);
739}
740
741static noinline_for_stack
742char *ip4_addr_string(char *buf, char *end, const u8 *addr,
743 struct printf_spec spec, const char *fmt)
744{
745 char ip4_addr[sizeof("255.255.255.255")];
746
747 ip4_string(ip4_addr, addr, fmt);
748
749 return string(buf, end, ip4_addr, spec);
750}
751
752static noinline_for_stack
753char *uuid_string(char *buf, char *end, const u8 *addr,
754 struct printf_spec spec, const char *fmt)
755{
756 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
757 char *p = uuid;
758 int i;
759 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
760 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
761 const u8 *index = be;
762 bool uc = false;
763
764 switch (*(++fmt)) {
765 case 'L':
766 uc = true; /* fall-through */
767 case 'l':
768 index = le;
769 break;
770 case 'B':
771 uc = true;
772 break;
773 }
774
775 for (i = 0; i < 16; i++) {
776 p = pack_hex_byte(p, addr[index[i]]);
777 switch (i) {
778 case 3:
779 case 5:
780 case 7:
781 case 9:
782 *p++ = '-';
783 break;
784 }
785 }
786
787 *p = 0;
788
789 if (uc) {
790 p = uuid;
791 do {
792 *p = toupper(*p);
793 } while (*(++p));
794 }
795
796 return string(buf, end, uuid, spec);
797}
798
799int kptr_restrict __read_mostly;
800
801/*
802 * Show a '%p' thing. A kernel extension is that the '%p' is followed
803 * by an extra set of alphanumeric characters that are extended format
804 * specifiers.
805 *
806 * Right now we handle:
807 *
808 * - 'F' For symbolic function descriptor pointers with offset
809 * - 'f' For simple symbolic function names without offset
810 * - 'S' For symbolic direct pointers with offset
811 * - 's' For symbolic direct pointers without offset
812 * - 'B' For backtraced symbolic direct pointers with offset
813 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
814 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
815 * - 'M' For a 6-byte MAC address, it prints the address in the
816 * usual colon-separated hex notation
817 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
818 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
819 * with a dash-separated hex notation
820 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
821 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
822 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
823 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
824 * IPv6 omits the colons (01020304...0f)
825 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
826 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
827 * - 'I6c' for IPv6 addresses printed as specified by
828 * http://tools.ietf.org/html/rfc5952
829 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
830 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
831 * Options for %pU are:
832 * b big endian lower case hex (default)
833 * B big endian UPPER case hex
834 * l little endian lower case hex
835 * L little endian UPPER case hex
836 * big endian output byte order is:
837 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
838 * little endian output byte order is:
839 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
840 * - 'V' For a struct va_format which contains a format string * and va_list *,
841 * call vsnprintf(->format, *->va_list).
842 * Implements a "recursive vsnprintf".
843 * Do not use this feature without some mechanism to verify the
844 * correctness of the format string and va_list arguments.
845 * - 'K' For a kernel pointer that should be hidden from unprivileged users
846 *
847 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
848 * function pointers are really function descriptors, which contain a
849 * pointer to the real address.
850 */
851static noinline_for_stack
852char *pointer(const char *fmt, char *buf, char *end, void *ptr,
853 struct printf_spec spec)
854{
855 if (!ptr && *fmt != 'K') {
856 /*
857 * Print (null) with the same width as a pointer so it makes
858 * tabular output look nice.
859 */
860 if (spec.field_width == -1)
861 spec.field_width = 2 * sizeof(void *);
862 return string(buf, end, "(null)", spec);
863 }
864
865 switch (*fmt) {
866 case 'F':
867 case 'f':
868 ptr = dereference_function_descriptor(ptr);
869 /* Fallthrough */
870 case 'S':
871 case 's':
872 case 'B':
873 return symbol_string(buf, end, ptr, spec, *fmt);
874 case 'R':
875 case 'r':
876 return resource_string(buf, end, ptr, spec, fmt);
877 case 'M': /* Colon separated: 00:01:02:03:04:05 */
878 case 'm': /* Contiguous: 000102030405 */
879 /* [mM]F (FDDI, bit reversed) */
880 return mac_address_string(buf, end, ptr, spec, fmt);
881 case 'I': /* Formatted IP supported
882 * 4: 1.2.3.4
883 * 6: 0001:0203:...:0708
884 * 6c: 1::708 or 1::1.2.3.4
885 */
886 case 'i': /* Contiguous:
887 * 4: 001.002.003.004
888 * 6: 000102...0f
889 */
890 switch (fmt[1]) {
891 case '6':
892 return ip6_addr_string(buf, end, ptr, spec, fmt);
893 case '4':
894 return ip4_addr_string(buf, end, ptr, spec, fmt);
895 }
896 break;
897 case 'U':
898 return uuid_string(buf, end, ptr, spec, fmt);
899 case 'V':
900 return buf + vsnprintf(buf, end > buf ? end - buf : 0,
901 ((struct va_format *)ptr)->fmt,
902 *(((struct va_format *)ptr)->va));
903 case 'K':
904 /*
905 * %pK cannot be used in IRQ context because its test
906 * for CAP_SYSLOG would be meaningless.
907 */
908 if (in_irq() || in_serving_softirq() || in_nmi()) {
909 if (spec.field_width == -1)
910 spec.field_width = 2 * sizeof(void *);
911 return string(buf, end, "pK-error", spec);
912 }
913 if (!((kptr_restrict == 0) ||
914 (kptr_restrict == 1 &&
915 has_capability_noaudit(current, CAP_SYSLOG))))
916 ptr = NULL;
917 break;
918 }
919 spec.flags |= SMALL;
920 if (spec.field_width == -1) {
921 spec.field_width = 2 * sizeof(void *);
922 spec.flags |= ZEROPAD;
923 }
924 spec.base = 16;
925
926 return number(buf, end, (unsigned long) ptr, spec);
927}
928
929/*
930 * Helper function to decode printf style format.
931 * Each call decode a token from the format and return the
932 * number of characters read (or likely the delta where it wants
933 * to go on the next call).
934 * The decoded token is returned through the parameters
935 *
936 * 'h', 'l', or 'L' for integer fields
937 * 'z' support added 23/7/1999 S.H.
938 * 'z' changed to 'Z' --davidm 1/25/99
939 * 't' added for ptrdiff_t
940 *
941 * @fmt: the format string
942 * @type of the token returned
943 * @flags: various flags such as +, -, # tokens..
944 * @field_width: overwritten width
945 * @base: base of the number (octal, hex, ...)
946 * @precision: precision of a number
947 * @qualifier: qualifier of a number (long, size_t, ...)
948 */
949static noinline_for_stack
950int format_decode(const char *fmt, struct printf_spec *spec)
951{
952 const char *start = fmt;
953
954 /* we finished early by reading the field width */
955 if (spec->type == FORMAT_TYPE_WIDTH) {
956 if (spec->field_width < 0) {
957 spec->field_width = -spec->field_width;
958 spec->flags |= LEFT;
959 }
960 spec->type = FORMAT_TYPE_NONE;
961 goto precision;
962 }
963
964 /* we finished early by reading the precision */
965 if (spec->type == FORMAT_TYPE_PRECISION) {
966 if (spec->precision < 0)
967 spec->precision = 0;
968
969 spec->type = FORMAT_TYPE_NONE;
970 goto qualifier;
971 }
972
973 /* By default */
974 spec->type = FORMAT_TYPE_NONE;
975
976 for (; *fmt ; ++fmt) {
977 if (*fmt == '%')
978 break;
979 }
980
981 /* Return the current non-format string */
982 if (fmt != start || !*fmt)
983 return fmt - start;
984
985 /* Process flags */
986 spec->flags = 0;
987
988 while (1) { /* this also skips first '%' */
989 bool found = true;
990
991 ++fmt;
992
993 switch (*fmt) {
994 case '-': spec->flags |= LEFT; break;
995 case '+': spec->flags |= PLUS; break;
996 case ' ': spec->flags |= SPACE; break;
997 case '#': spec->flags |= SPECIAL; break;
998 case '0': spec->flags |= ZEROPAD; break;
999 default: found = false;
1000 }
1001
1002 if (!found)
1003 break;
1004 }
1005
1006 /* get field width */
1007 spec->field_width = -1;
1008
1009 if (isdigit(*fmt))
1010 spec->field_width = skip_atoi(&fmt);
1011 else if (*fmt == '*') {
1012 /* it's the next argument */
1013 spec->type = FORMAT_TYPE_WIDTH;
1014 return ++fmt - start;
1015 }
1016
1017precision:
1018 /* get the precision */
1019 spec->precision = -1;
1020 if (*fmt == '.') {
1021 ++fmt;
1022 if (isdigit(*fmt)) {
1023 spec->precision = skip_atoi(&fmt);
1024 if (spec->precision < 0)
1025 spec->precision = 0;
1026 } else if (*fmt == '*') {
1027 /* it's the next argument */
1028 spec->type = FORMAT_TYPE_PRECISION;
1029 return ++fmt - start;
1030 }
1031 }
1032
1033qualifier:
1034 /* get the conversion qualifier */
1035 spec->qualifier = -1;
1036 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1037 _tolower(*fmt) == 'z' || *fmt == 't') {
1038 spec->qualifier = *fmt++;
1039 if (unlikely(spec->qualifier == *fmt)) {
1040 if (spec->qualifier == 'l') {
1041 spec->qualifier = 'L';
1042 ++fmt;
1043 } else if (spec->qualifier == 'h') {
1044 spec->qualifier = 'H';
1045 ++fmt;
1046 }
1047 }
1048 }
1049
1050 /* default base */
1051 spec->base = 10;
1052 switch (*fmt) {
1053 case 'c':
1054 spec->type = FORMAT_TYPE_CHAR;
1055 return ++fmt - start;
1056
1057 case 's':
1058 spec->type = FORMAT_TYPE_STR;
1059 return ++fmt - start;
1060
1061 case 'p':
1062 spec->type = FORMAT_TYPE_PTR;
1063 return fmt - start;
1064 /* skip alnum */
1065
1066 case 'n':
1067 spec->type = FORMAT_TYPE_NRCHARS;
1068 return ++fmt - start;
1069
1070 case '%':
1071 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1072 return ++fmt - start;
1073
1074 /* integer number formats - set up the flags and "break" */
1075 case 'o':
1076 spec->base = 8;
1077 break;
1078
1079 case 'x':
1080 spec->flags |= SMALL;
1081
1082 case 'X':
1083 spec->base = 16;
1084 break;
1085
1086 case 'd':
1087 case 'i':
1088 spec->flags |= SIGN;
1089 case 'u':
1090 break;
1091
1092 default:
1093 spec->type = FORMAT_TYPE_INVALID;
1094 return fmt - start;
1095 }
1096
1097 if (spec->qualifier == 'L')
1098 spec->type = FORMAT_TYPE_LONG_LONG;
1099 else if (spec->qualifier == 'l') {
1100 if (spec->flags & SIGN)
1101 spec->type = FORMAT_TYPE_LONG;
1102 else
1103 spec->type = FORMAT_TYPE_ULONG;
1104 } else if (_tolower(spec->qualifier) == 'z') {
1105 spec->type = FORMAT_TYPE_SIZE_T;
1106 } else if (spec->qualifier == 't') {
1107 spec->type = FORMAT_TYPE_PTRDIFF;
1108 } else if (spec->qualifier == 'H') {
1109 if (spec->flags & SIGN)
1110 spec->type = FORMAT_TYPE_BYTE;
1111 else
1112 spec->type = FORMAT_TYPE_UBYTE;
1113 } else if (spec->qualifier == 'h') {
1114 if (spec->flags & SIGN)
1115 spec->type = FORMAT_TYPE_SHORT;
1116 else
1117 spec->type = FORMAT_TYPE_USHORT;
1118 } else {
1119 if (spec->flags & SIGN)
1120 spec->type = FORMAT_TYPE_INT;
1121 else
1122 spec->type = FORMAT_TYPE_UINT;
1123 }
1124
1125 return ++fmt - start;
1126}
1127
1128/**
1129 * vsnprintf - Format a string and place it in a buffer
1130 * @buf: The buffer to place the result into
1131 * @size: The size of the buffer, including the trailing null space
1132 * @fmt: The format string to use
1133 * @args: Arguments for the format string
1134 *
1135 * This function follows C99 vsnprintf, but has some extensions:
1136 * %pS output the name of a text symbol with offset
1137 * %ps output the name of a text symbol without offset
1138 * %pF output the name of a function pointer with its offset
1139 * %pf output the name of a function pointer without its offset
1140 * %pB output the name of a backtrace symbol with its offset
1141 * %pR output the address range in a struct resource with decoded flags
1142 * %pr output the address range in a struct resource with raw flags
1143 * %pM output a 6-byte MAC address with colons
1144 * %pm output a 6-byte MAC address without colons
1145 * %pI4 print an IPv4 address without leading zeros
1146 * %pi4 print an IPv4 address with leading zeros
1147 * %pI6 print an IPv6 address with colons
1148 * %pi6 print an IPv6 address without colons
1149 * %pI6c print an IPv6 address as specified by RFC 5952
1150 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1151 * case.
1152 * %n is ignored
1153 *
1154 * The return value is the number of characters which would
1155 * be generated for the given input, excluding the trailing
1156 * '\0', as per ISO C99. If you want to have the exact
1157 * number of characters written into @buf as return value
1158 * (not including the trailing '\0'), use vscnprintf(). If the
1159 * return is greater than or equal to @size, the resulting
1160 * string is truncated.
1161 *
1162 * If you're not already dealing with a va_list consider using snprintf().
1163 */
1164int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1165{
1166 unsigned long long num;
1167 char *str, *end;
1168 struct printf_spec spec = {0};
1169
1170 /* Reject out-of-range values early. Large positive sizes are
1171 used for unknown buffer sizes. */
1172 if (WARN_ON_ONCE((int) size < 0))
1173 return 0;
1174
1175 str = buf;
1176 end = buf + size;
1177
1178 /* Make sure end is always >= buf */
1179 if (end < buf) {
1180 end = ((void *)-1);
1181 size = end - buf;
1182 }
1183
1184 while (*fmt) {
1185 const char *old_fmt = fmt;
1186 int read = format_decode(fmt, &spec);
1187
1188 fmt += read;
1189
1190 switch (spec.type) {
1191 case FORMAT_TYPE_NONE: {
1192 int copy = read;
1193 if (str < end) {
1194 if (copy > end - str)
1195 copy = end - str;
1196 memcpy(str, old_fmt, copy);
1197 }
1198 str += read;
1199 break;
1200 }
1201
1202 case FORMAT_TYPE_WIDTH:
1203 spec.field_width = va_arg(args, int);
1204 break;
1205
1206 case FORMAT_TYPE_PRECISION:
1207 spec.precision = va_arg(args, int);
1208 break;
1209
1210 case FORMAT_TYPE_CHAR: {
1211 char c;
1212
1213 if (!(spec.flags & LEFT)) {
1214 while (--spec.field_width > 0) {
1215 if (str < end)
1216 *str = ' ';
1217 ++str;
1218
1219 }
1220 }
1221 c = (unsigned char) va_arg(args, int);
1222 if (str < end)
1223 *str = c;
1224 ++str;
1225 while (--spec.field_width > 0) {
1226 if (str < end)
1227 *str = ' ';
1228 ++str;
1229 }
1230 break;
1231 }
1232
1233 case FORMAT_TYPE_STR:
1234 str = string(str, end, va_arg(args, char *), spec);
1235 break;
1236
1237 case FORMAT_TYPE_PTR:
1238 str = pointer(fmt+1, str, end, va_arg(args, void *),
1239 spec);
1240 while (isalnum(*fmt))
1241 fmt++;
1242 break;
1243
1244 case FORMAT_TYPE_PERCENT_CHAR:
1245 if (str < end)
1246 *str = '%';
1247 ++str;
1248 break;
1249
1250 case FORMAT_TYPE_INVALID:
1251 if (str < end)
1252 *str = '%';
1253 ++str;
1254 break;
1255
1256 case FORMAT_TYPE_NRCHARS: {
1257 u8 qualifier = spec.qualifier;
1258
1259 if (qualifier == 'l') {
1260 long *ip = va_arg(args, long *);
1261 *ip = (str - buf);
1262 } else if (_tolower(qualifier) == 'z') {
1263 size_t *ip = va_arg(args, size_t *);
1264 *ip = (str - buf);
1265 } else {
1266 int *ip = va_arg(args, int *);
1267 *ip = (str - buf);
1268 }
1269 break;
1270 }
1271
1272 default:
1273 switch (spec.type) {
1274 case FORMAT_TYPE_LONG_LONG:
1275 num = va_arg(args, long long);
1276 break;
1277 case FORMAT_TYPE_ULONG:
1278 num = va_arg(args, unsigned long);
1279 break;
1280 case FORMAT_TYPE_LONG:
1281 num = va_arg(args, long);
1282 break;
1283 case FORMAT_TYPE_SIZE_T:
1284 num = va_arg(args, size_t);
1285 break;
1286 case FORMAT_TYPE_PTRDIFF:
1287 num = va_arg(args, ptrdiff_t);
1288 break;
1289 case FORMAT_TYPE_UBYTE:
1290 num = (unsigned char) va_arg(args, int);
1291 break;
1292 case FORMAT_TYPE_BYTE:
1293 num = (signed char) va_arg(args, int);
1294 break;
1295 case FORMAT_TYPE_USHORT:
1296 num = (unsigned short) va_arg(args, int);
1297 break;
1298 case FORMAT_TYPE_SHORT:
1299 num = (short) va_arg(args, int);
1300 break;
1301 case FORMAT_TYPE_INT:
1302 num = (int) va_arg(args, int);
1303 break;
1304 default:
1305 num = va_arg(args, unsigned int);
1306 }
1307
1308 str = number(str, end, num, spec);
1309 }
1310 }
1311
1312 if (size > 0) {
1313 if (str < end)
1314 *str = '\0';
1315 else
1316 end[-1] = '\0';
1317 }
1318
1319 /* the trailing null byte doesn't count towards the total */
1320 return str-buf;
1321
1322}
1323EXPORT_SYMBOL(vsnprintf);
1324
1325/**
1326 * vscnprintf - Format a string and place it in a buffer
1327 * @buf: The buffer to place the result into
1328 * @size: The size of the buffer, including the trailing null space
1329 * @fmt: The format string to use
1330 * @args: Arguments for the format string
1331 *
1332 * The return value is the number of characters which have been written into
1333 * the @buf not including the trailing '\0'. If @size is == 0 the function
1334 * returns 0.
1335 *
1336 * If you're not already dealing with a va_list consider using scnprintf().
1337 *
1338 * See the vsnprintf() documentation for format string extensions over C99.
1339 */
1340int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1341{
1342 int i;
1343
1344 i = vsnprintf(buf, size, fmt, args);
1345
1346 if (likely(i < size))
1347 return i;
1348 if (size != 0)
1349 return size - 1;
1350 return 0;
1351}
1352EXPORT_SYMBOL(vscnprintf);
1353
1354/**
1355 * snprintf - Format a string and place it in a buffer
1356 * @buf: The buffer to place the result into
1357 * @size: The size of the buffer, including the trailing null space
1358 * @fmt: The format string to use
1359 * @...: Arguments for the format string
1360 *
1361 * The return value is the number of characters which would be
1362 * generated for the given input, excluding the trailing null,
1363 * as per ISO C99. If the return is greater than or equal to
1364 * @size, the resulting string is truncated.
1365 *
1366 * See the vsnprintf() documentation for format string extensions over C99.
1367 */
1368int snprintf(char *buf, size_t size, const char *fmt, ...)
1369{
1370 va_list args;
1371 int i;
1372
1373 va_start(args, fmt);
1374 i = vsnprintf(buf, size, fmt, args);
1375 va_end(args);
1376
1377 return i;
1378}
1379EXPORT_SYMBOL(snprintf);
1380
1381/**
1382 * scnprintf - Format a string and place it in a buffer
1383 * @buf: The buffer to place the result into
1384 * @size: The size of the buffer, including the trailing null space
1385 * @fmt: The format string to use
1386 * @...: Arguments for the format string
1387 *
1388 * The return value is the number of characters written into @buf not including
1389 * the trailing '\0'. If @size is == 0 the function returns 0.
1390 */
1391
1392int scnprintf(char *buf, size_t size, const char *fmt, ...)
1393{
1394 va_list args;
1395 int i;
1396
1397 va_start(args, fmt);
1398 i = vscnprintf(buf, size, fmt, args);
1399 va_end(args);
1400
1401 return i;
1402}
1403EXPORT_SYMBOL(scnprintf);
1404
1405/**
1406 * vsprintf - Format a string and place it in a buffer
1407 * @buf: The buffer to place the result into
1408 * @fmt: The format string to use
1409 * @args: Arguments for the format string
1410 *
1411 * The function returns the number of characters written
1412 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1413 * buffer overflows.
1414 *
1415 * If you're not already dealing with a va_list consider using sprintf().
1416 *
1417 * See the vsnprintf() documentation for format string extensions over C99.
1418 */
1419int vsprintf(char *buf, const char *fmt, va_list args)
1420{
1421 return vsnprintf(buf, INT_MAX, fmt, args);
1422}
1423EXPORT_SYMBOL(vsprintf);
1424
1425/**
1426 * sprintf - Format a string and place it in a buffer
1427 * @buf: The buffer to place the result into
1428 * @fmt: The format string to use
1429 * @...: Arguments for the format string
1430 *
1431 * The function returns the number of characters written
1432 * into @buf. Use snprintf() or scnprintf() in order to avoid
1433 * buffer overflows.
1434 *
1435 * See the vsnprintf() documentation for format string extensions over C99.
1436 */
1437int sprintf(char *buf, const char *fmt, ...)
1438{
1439 va_list args;
1440 int i;
1441
1442 va_start(args, fmt);
1443 i = vsnprintf(buf, INT_MAX, fmt, args);
1444 va_end(args);
1445
1446 return i;
1447}
1448EXPORT_SYMBOL(sprintf);
1449
1450#ifdef CONFIG_BINARY_PRINTF
1451/*
1452 * bprintf service:
1453 * vbin_printf() - VA arguments to binary data
1454 * bstr_printf() - Binary data to text string
1455 */
1456
1457/**
1458 * vbin_printf - Parse a format string and place args' binary value in a buffer
1459 * @bin_buf: The buffer to place args' binary value
1460 * @size: The size of the buffer(by words(32bits), not characters)
1461 * @fmt: The format string to use
1462 * @args: Arguments for the format string
1463 *
1464 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1465 * is skiped.
1466 *
1467 * The return value is the number of words(32bits) which would be generated for
1468 * the given input.
1469 *
1470 * NOTE:
1471 * If the return value is greater than @size, the resulting bin_buf is NOT
1472 * valid for bstr_printf().
1473 */
1474int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1475{
1476 struct printf_spec spec = {0};
1477 char *str, *end;
1478
1479 str = (char *)bin_buf;
1480 end = (char *)(bin_buf + size);
1481
1482#define save_arg(type) \
1483do { \
1484 if (sizeof(type) == 8) { \
1485 unsigned long long value; \
1486 str = PTR_ALIGN(str, sizeof(u32)); \
1487 value = va_arg(args, unsigned long long); \
1488 if (str + sizeof(type) <= end) { \
1489 *(u32 *)str = *(u32 *)&value; \
1490 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1491 } \
1492 } else { \
1493 unsigned long value; \
1494 str = PTR_ALIGN(str, sizeof(type)); \
1495 value = va_arg(args, int); \
1496 if (str + sizeof(type) <= end) \
1497 *(typeof(type) *)str = (type)value; \
1498 } \
1499 str += sizeof(type); \
1500} while (0)
1501
1502 while (*fmt) {
1503 int read = format_decode(fmt, &spec);
1504
1505 fmt += read;
1506
1507 switch (spec.type) {
1508 case FORMAT_TYPE_NONE:
1509 case FORMAT_TYPE_INVALID:
1510 case FORMAT_TYPE_PERCENT_CHAR:
1511 break;
1512
1513 case FORMAT_TYPE_WIDTH:
1514 case FORMAT_TYPE_PRECISION:
1515 save_arg(int);
1516 break;
1517
1518 case FORMAT_TYPE_CHAR:
1519 save_arg(char);
1520 break;
1521
1522 case FORMAT_TYPE_STR: {
1523 const char *save_str = va_arg(args, char *);
1524 size_t len;
1525
1526 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1527 || (unsigned long)save_str < PAGE_SIZE)
1528 save_str = "(null)";
1529 len = strlen(save_str) + 1;
1530 if (str + len < end)
1531 memcpy(str, save_str, len);
1532 str += len;
1533 break;
1534 }
1535
1536 case FORMAT_TYPE_PTR:
1537 save_arg(void *);
1538 /* skip all alphanumeric pointer suffixes */
1539 while (isalnum(*fmt))
1540 fmt++;
1541 break;
1542
1543 case FORMAT_TYPE_NRCHARS: {
1544 /* skip %n 's argument */
1545 u8 qualifier = spec.qualifier;
1546 void *skip_arg;
1547 if (qualifier == 'l')
1548 skip_arg = va_arg(args, long *);
1549 else if (_tolower(qualifier) == 'z')
1550 skip_arg = va_arg(args, size_t *);
1551 else
1552 skip_arg = va_arg(args, int *);
1553 break;
1554 }
1555
1556 default:
1557 switch (spec.type) {
1558
1559 case FORMAT_TYPE_LONG_LONG:
1560 save_arg(long long);
1561 break;
1562 case FORMAT_TYPE_ULONG:
1563 case FORMAT_TYPE_LONG:
1564 save_arg(unsigned long);
1565 break;
1566 case FORMAT_TYPE_SIZE_T:
1567 save_arg(size_t);
1568 break;
1569 case FORMAT_TYPE_PTRDIFF:
1570 save_arg(ptrdiff_t);
1571 break;
1572 case FORMAT_TYPE_UBYTE:
1573 case FORMAT_TYPE_BYTE:
1574 save_arg(char);
1575 break;
1576 case FORMAT_TYPE_USHORT:
1577 case FORMAT_TYPE_SHORT:
1578 save_arg(short);
1579 break;
1580 default:
1581 save_arg(int);
1582 }
1583 }
1584 }
1585
1586 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1587#undef save_arg
1588}
1589EXPORT_SYMBOL_GPL(vbin_printf);
1590
1591/**
1592 * bstr_printf - Format a string from binary arguments and place it in a buffer
1593 * @buf: The buffer to place the result into
1594 * @size: The size of the buffer, including the trailing null space
1595 * @fmt: The format string to use
1596 * @bin_buf: Binary arguments for the format string
1597 *
1598 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1599 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1600 * a binary buffer that generated by vbin_printf.
1601 *
1602 * The format follows C99 vsnprintf, but has some extensions:
1603 * see vsnprintf comment for details.
1604 *
1605 * The return value is the number of characters which would
1606 * be generated for the given input, excluding the trailing
1607 * '\0', as per ISO C99. If you want to have the exact
1608 * number of characters written into @buf as return value
1609 * (not including the trailing '\0'), use vscnprintf(). If the
1610 * return is greater than or equal to @size, the resulting
1611 * string is truncated.
1612 */
1613int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1614{
1615 struct printf_spec spec = {0};
1616 char *str, *end;
1617 const char *args = (const char *)bin_buf;
1618
1619 if (WARN_ON_ONCE((int) size < 0))
1620 return 0;
1621
1622 str = buf;
1623 end = buf + size;
1624
1625#define get_arg(type) \
1626({ \
1627 typeof(type) value; \
1628 if (sizeof(type) == 8) { \
1629 args = PTR_ALIGN(args, sizeof(u32)); \
1630 *(u32 *)&value = *(u32 *)args; \
1631 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1632 } else { \
1633 args = PTR_ALIGN(args, sizeof(type)); \
1634 value = *(typeof(type) *)args; \
1635 } \
1636 args += sizeof(type); \
1637 value; \
1638})
1639
1640 /* Make sure end is always >= buf */
1641 if (end < buf) {
1642 end = ((void *)-1);
1643 size = end - buf;
1644 }
1645
1646 while (*fmt) {
1647 const char *old_fmt = fmt;
1648 int read = format_decode(fmt, &spec);
1649
1650 fmt += read;
1651
1652 switch (spec.type) {
1653 case FORMAT_TYPE_NONE: {
1654 int copy = read;
1655 if (str < end) {
1656 if (copy > end - str)
1657 copy = end - str;
1658 memcpy(str, old_fmt, copy);
1659 }
1660 str += read;
1661 break;
1662 }
1663
1664 case FORMAT_TYPE_WIDTH:
1665 spec.field_width = get_arg(int);
1666 break;
1667
1668 case FORMAT_TYPE_PRECISION:
1669 spec.precision = get_arg(int);
1670 break;
1671
1672 case FORMAT_TYPE_CHAR: {
1673 char c;
1674
1675 if (!(spec.flags & LEFT)) {
1676 while (--spec.field_width > 0) {
1677 if (str < end)
1678 *str = ' ';
1679 ++str;
1680 }
1681 }
1682 c = (unsigned char) get_arg(char);
1683 if (str < end)
1684 *str = c;
1685 ++str;
1686 while (--spec.field_width > 0) {
1687 if (str < end)
1688 *str = ' ';
1689 ++str;
1690 }
1691 break;
1692 }
1693
1694 case FORMAT_TYPE_STR: {
1695 const char *str_arg = args;
1696 args += strlen(str_arg) + 1;
1697 str = string(str, end, (char *)str_arg, spec);
1698 break;
1699 }
1700
1701 case FORMAT_TYPE_PTR:
1702 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1703 while (isalnum(*fmt))
1704 fmt++;
1705 break;
1706
1707 case FORMAT_TYPE_PERCENT_CHAR:
1708 case FORMAT_TYPE_INVALID:
1709 if (str < end)
1710 *str = '%';
1711 ++str;
1712 break;
1713
1714 case FORMAT_TYPE_NRCHARS:
1715 /* skip */
1716 break;
1717
1718 default: {
1719 unsigned long long num;
1720
1721 switch (spec.type) {
1722
1723 case FORMAT_TYPE_LONG_LONG:
1724 num = get_arg(long long);
1725 break;
1726 case FORMAT_TYPE_ULONG:
1727 case FORMAT_TYPE_LONG:
1728 num = get_arg(unsigned long);
1729 break;
1730 case FORMAT_TYPE_SIZE_T:
1731 num = get_arg(size_t);
1732 break;
1733 case FORMAT_TYPE_PTRDIFF:
1734 num = get_arg(ptrdiff_t);
1735 break;
1736 case FORMAT_TYPE_UBYTE:
1737 num = get_arg(unsigned char);
1738 break;
1739 case FORMAT_TYPE_BYTE:
1740 num = get_arg(signed char);
1741 break;
1742 case FORMAT_TYPE_USHORT:
1743 num = get_arg(unsigned short);
1744 break;
1745 case FORMAT_TYPE_SHORT:
1746 num = get_arg(short);
1747 break;
1748 case FORMAT_TYPE_UINT:
1749 num = get_arg(unsigned int);
1750 break;
1751 default:
1752 num = get_arg(int);
1753 }
1754
1755 str = number(str, end, num, spec);
1756 } /* default: */
1757 } /* switch(spec.type) */
1758 } /* while(*fmt) */
1759
1760 if (size > 0) {
1761 if (str < end)
1762 *str = '\0';
1763 else
1764 end[-1] = '\0';
1765 }
1766
1767#undef get_arg
1768
1769 /* the trailing null byte doesn't count towards the total */
1770 return str - buf;
1771}
1772EXPORT_SYMBOL_GPL(bstr_printf);
1773
1774/**
1775 * bprintf - Parse a format string and place args' binary value in a buffer
1776 * @bin_buf: The buffer to place args' binary value
1777 * @size: The size of the buffer(by words(32bits), not characters)
1778 * @fmt: The format string to use
1779 * @...: Arguments for the format string
1780 *
1781 * The function returns the number of words(u32) written
1782 * into @bin_buf.
1783 */
1784int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1785{
1786 va_list args;
1787 int ret;
1788
1789 va_start(args, fmt);
1790 ret = vbin_printf(bin_buf, size, fmt, args);
1791 va_end(args);
1792
1793 return ret;
1794}
1795EXPORT_SYMBOL_GPL(bprintf);
1796
1797#endif /* CONFIG_BINARY_PRINTF */
1798
1799/**
1800 * vsscanf - Unformat a buffer into a list of arguments
1801 * @buf: input buffer
1802 * @fmt: format of buffer
1803 * @args: arguments
1804 */
1805int vsscanf(const char *buf, const char *fmt, va_list args)
1806{
1807 const char *str = buf;
1808 char *next;
1809 char digit;
1810 int num = 0;
1811 u8 qualifier;
1812 u8 base;
1813 s16 field_width;
1814 bool is_sign;
1815
1816 while (*fmt && *str) {
1817 /* skip any white space in format */
1818 /* white space in format matchs any amount of
1819 * white space, including none, in the input.
1820 */
1821 if (isspace(*fmt)) {
1822 fmt = skip_spaces(++fmt);
1823 str = skip_spaces(str);
1824 }
1825
1826 /* anything that is not a conversion must match exactly */
1827 if (*fmt != '%' && *fmt) {
1828 if (*fmt++ != *str++)
1829 break;
1830 continue;
1831 }
1832
1833 if (!*fmt)
1834 break;
1835 ++fmt;
1836
1837 /* skip this conversion.
1838 * advance both strings to next white space
1839 */
1840 if (*fmt == '*') {
1841 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1842 fmt++;
1843 while (!isspace(*str) && *str)
1844 str++;
1845 continue;
1846 }
1847
1848 /* get field width */
1849 field_width = -1;
1850 if (isdigit(*fmt))
1851 field_width = skip_atoi(&fmt);
1852
1853 /* get conversion qualifier */
1854 qualifier = -1;
1855 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1856 _tolower(*fmt) == 'z') {
1857 qualifier = *fmt++;
1858 if (unlikely(qualifier == *fmt)) {
1859 if (qualifier == 'h') {
1860 qualifier = 'H';
1861 fmt++;
1862 } else if (qualifier == 'l') {
1863 qualifier = 'L';
1864 fmt++;
1865 }
1866 }
1867 }
1868
1869 if (!*fmt || !*str)
1870 break;
1871
1872 base = 10;
1873 is_sign = 0;
1874
1875 switch (*fmt++) {
1876 case 'c':
1877 {
1878 char *s = (char *)va_arg(args, char*);
1879 if (field_width == -1)
1880 field_width = 1;
1881 do {
1882 *s++ = *str++;
1883 } while (--field_width > 0 && *str);
1884 num++;
1885 }
1886 continue;
1887 case 's':
1888 {
1889 char *s = (char *)va_arg(args, char *);
1890 if (field_width == -1)
1891 field_width = SHRT_MAX;
1892 /* first, skip leading white space in buffer */
1893 str = skip_spaces(str);
1894
1895 /* now copy until next white space */
1896 while (*str && !isspace(*str) && field_width--)
1897 *s++ = *str++;
1898 *s = '\0';
1899 num++;
1900 }
1901 continue;
1902 case 'n':
1903 /* return number of characters read so far */
1904 {
1905 int *i = (int *)va_arg(args, int*);
1906 *i = str - buf;
1907 }
1908 continue;
1909 case 'o':
1910 base = 8;
1911 break;
1912 case 'x':
1913 case 'X':
1914 base = 16;
1915 break;
1916 case 'i':
1917 base = 0;
1918 case 'd':
1919 is_sign = 1;
1920 case 'u':
1921 break;
1922 case '%':
1923 /* looking for '%' in str */
1924 if (*str++ != '%')
1925 return num;
1926 continue;
1927 default:
1928 /* invalid format; stop here */
1929 return num;
1930 }
1931
1932 /* have some sort of integer conversion.
1933 * first, skip white space in buffer.
1934 */
1935 str = skip_spaces(str);
1936
1937 digit = *str;
1938 if (is_sign && digit == '-')
1939 digit = *(str + 1);
1940
1941 if (!digit
1942 || (base == 16 && !isxdigit(digit))
1943 || (base == 10 && !isdigit(digit))
1944 || (base == 8 && (!isdigit(digit) || digit > '7'))
1945 || (base == 0 && !isdigit(digit)))
1946 break;
1947
1948 switch (qualifier) {
1949 case 'H': /* that's 'hh' in format */
1950 if (is_sign) {
1951 signed char *s = (signed char *)va_arg(args, signed char *);
1952 *s = (signed char)simple_strtol(str, &next, base);
1953 } else {
1954 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1955 *s = (unsigned char)simple_strtoul(str, &next, base);
1956 }
1957 break;
1958 case 'h':
1959 if (is_sign) {
1960 short *s = (short *)va_arg(args, short *);
1961 *s = (short)simple_strtol(str, &next, base);
1962 } else {
1963 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1964 *s = (unsigned short)simple_strtoul(str, &next, base);
1965 }
1966 break;
1967 case 'l':
1968 if (is_sign) {
1969 long *l = (long *)va_arg(args, long *);
1970 *l = simple_strtol(str, &next, base);
1971 } else {
1972 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1973 *l = simple_strtoul(str, &next, base);
1974 }
1975 break;
1976 case 'L':
1977 if (is_sign) {
1978 long long *l = (long long *)va_arg(args, long long *);
1979 *l = simple_strtoll(str, &next, base);
1980 } else {
1981 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1982 *l = simple_strtoull(str, &next, base);
1983 }
1984 break;
1985 case 'Z':
1986 case 'z':
1987 {
1988 size_t *s = (size_t *)va_arg(args, size_t *);
1989 *s = (size_t)simple_strtoul(str, &next, base);
1990 }
1991 break;
1992 default:
1993 if (is_sign) {
1994 int *i = (int *)va_arg(args, int *);
1995 *i = (int)simple_strtol(str, &next, base);
1996 } else {
1997 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
1998 *i = (unsigned int)simple_strtoul(str, &next, base);
1999 }
2000 break;
2001 }
2002 num++;
2003
2004 if (!next)
2005 break;
2006 str = next;
2007 }
2008
2009 /*
2010 * Now we've come all the way through so either the input string or the
2011 * format ended. In the former case, there can be a %n at the current
2012 * position in the format that needs to be filled.
2013 */
2014 if (*fmt == '%' && *(fmt + 1) == 'n') {
2015 int *p = (int *)va_arg(args, int *);
2016 *p = str - buf;
2017 }
2018
2019 return num;
2020}
2021EXPORT_SYMBOL(vsscanf);
2022
2023/**
2024 * sscanf - Unformat a buffer into a list of arguments
2025 * @buf: input buffer
2026 * @fmt: formatting of buffer
2027 * @...: resulting arguments
2028 */
2029int sscanf(const char *buf, const char *fmt, ...)
2030{
2031 va_list args;
2032 int i;
2033
2034 va_start(args, fmt);
2035 i = vsscanf(buf, fmt, args);
2036 va_end(args);
2037
2038 return i;
2039}
2040EXPORT_SYMBOL(sscanf);