net/netfilter/nf_conntrack_core: Fix net_conntrack_lock()
[linux/fpc-iii.git] / lib / vsprintf.c
blob86c3385b9eb393a54b09cddcfcccef3ec257f8d2
1 /*
2 * linux/lib/vsprintf.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8 /*
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
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
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 <linux/of.h>
35 #include <net/addrconf.h>
36 #ifdef CONFIG_BLOCK
37 #include <linux/blkdev.h>
38 #endif
40 #include "../mm/internal.h" /* For the trace_print_flags arrays */
42 #include <asm/page.h> /* for PAGE_SIZE */
43 #include <asm/sections.h> /* for dereference_function_descriptor() */
44 #include <asm/byteorder.h> /* cpu_to_le16 */
46 #include <linux/string_helpers.h>
47 #include "kstrtox.h"
49 /**
50 * simple_strtoull - convert a string to an unsigned long long
51 * @cp: The start of the string
52 * @endp: A pointer to the end of the parsed string will be placed here
53 * @base: The number base to use
55 * This function is obsolete. Please use kstrtoull instead.
57 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
59 unsigned long long result;
60 unsigned int rv;
62 cp = _parse_integer_fixup_radix(cp, &base);
63 rv = _parse_integer(cp, base, &result);
64 /* FIXME */
65 cp += (rv & ~KSTRTOX_OVERFLOW);
67 if (endp)
68 *endp = (char *)cp;
70 return result;
72 EXPORT_SYMBOL(simple_strtoull);
74 /**
75 * simple_strtoul - convert a string to an unsigned long
76 * @cp: The start of the string
77 * @endp: A pointer to the end of the parsed string will be placed here
78 * @base: The number base to use
80 * This function is obsolete. Please use kstrtoul instead.
82 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
84 return simple_strtoull(cp, endp, base);
86 EXPORT_SYMBOL(simple_strtoul);
88 /**
89 * simple_strtol - convert a string to a signed long
90 * @cp: The start of the string
91 * @endp: A pointer to the end of the parsed string will be placed here
92 * @base: The number base to use
94 * This function is obsolete. Please use kstrtol instead.
96 long simple_strtol(const char *cp, char **endp, unsigned int base)
98 if (*cp == '-')
99 return -simple_strtoul(cp + 1, endp, base);
101 return simple_strtoul(cp, endp, base);
103 EXPORT_SYMBOL(simple_strtol);
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
111 * This function is obsolete. Please use kstrtoll instead.
113 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
115 if (*cp == '-')
116 return -simple_strtoull(cp + 1, endp, base);
118 return simple_strtoull(cp, endp, base);
120 EXPORT_SYMBOL(simple_strtoll);
122 static noinline_for_stack
123 int skip_atoi(const char **s)
125 int i = 0;
127 do {
128 i = i*10 + *((*s)++) - '0';
129 } while (isdigit(**s));
131 return i;
135 * Decimal conversion is by far the most typical, and is used for
136 * /proc and /sys data. This directly impacts e.g. top performance
137 * with many processes running. We optimize it for speed by emitting
138 * two characters at a time, using a 200 byte lookup table. This
139 * roughly halves the number of multiplications compared to computing
140 * the digits one at a time. Implementation strongly inspired by the
141 * previous version, which in turn used ideas described at
142 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
143 * from the author, Douglas W. Jones).
145 * It turns out there is precisely one 26 bit fixed-point
146 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
147 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
148 * range happens to be somewhat larger (x <= 1073741898), but that's
149 * irrelevant for our purpose.
151 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
152 * need a 32x32->64 bit multiply, so we simply use the same constant.
154 * For dividing a number in the range [100, 10^4-1] by 100, there are
155 * several options. The simplest is (x * 0x147b) >> 19, which is valid
156 * for all x <= 43698.
159 static const u16 decpair[100] = {
160 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
161 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
162 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
163 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
164 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
165 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
166 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
167 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
168 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
169 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
170 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
171 #undef _
175 * This will print a single '0' even if r == 0, since we would
176 * immediately jump to out_r where two 0s would be written but only
177 * one of them accounted for in buf. This is needed by ip4_string
178 * below. All other callers pass a non-zero value of r.
180 static noinline_for_stack
181 char *put_dec_trunc8(char *buf, unsigned r)
183 unsigned q;
185 /* 1 <= r < 10^8 */
186 if (r < 100)
187 goto out_r;
189 /* 100 <= r < 10^8 */
190 q = (r * (u64)0x28f5c29) >> 32;
191 *((u16 *)buf) = decpair[r - 100*q];
192 buf += 2;
194 /* 1 <= q < 10^6 */
195 if (q < 100)
196 goto out_q;
198 /* 100 <= q < 10^6 */
199 r = (q * (u64)0x28f5c29) >> 32;
200 *((u16 *)buf) = decpair[q - 100*r];
201 buf += 2;
203 /* 1 <= r < 10^4 */
204 if (r < 100)
205 goto out_r;
207 /* 100 <= r < 10^4 */
208 q = (r * 0x147b) >> 19;
209 *((u16 *)buf) = decpair[r - 100*q];
210 buf += 2;
211 out_q:
212 /* 1 <= q < 100 */
213 r = q;
214 out_r:
215 /* 1 <= r < 100 */
216 *((u16 *)buf) = decpair[r];
217 buf += r < 10 ? 1 : 2;
218 return buf;
221 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
222 static noinline_for_stack
223 char *put_dec_full8(char *buf, unsigned r)
225 unsigned q;
227 /* 0 <= r < 10^8 */
228 q = (r * (u64)0x28f5c29) >> 32;
229 *((u16 *)buf) = decpair[r - 100*q];
230 buf += 2;
232 /* 0 <= q < 10^6 */
233 r = (q * (u64)0x28f5c29) >> 32;
234 *((u16 *)buf) = decpair[q - 100*r];
235 buf += 2;
237 /* 0 <= r < 10^4 */
238 q = (r * 0x147b) >> 19;
239 *((u16 *)buf) = decpair[r - 100*q];
240 buf += 2;
242 /* 0 <= q < 100 */
243 *((u16 *)buf) = decpair[q];
244 buf += 2;
245 return buf;
248 static noinline_for_stack
249 char *put_dec(char *buf, unsigned long long n)
251 if (n >= 100*1000*1000)
252 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
253 /* 1 <= n <= 1.6e11 */
254 if (n >= 100*1000*1000)
255 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
256 /* 1 <= n < 1e8 */
257 return put_dec_trunc8(buf, n);
260 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
262 static void
263 put_dec_full4(char *buf, unsigned r)
265 unsigned q;
267 /* 0 <= r < 10^4 */
268 q = (r * 0x147b) >> 19;
269 *((u16 *)buf) = decpair[r - 100*q];
270 buf += 2;
271 /* 0 <= q < 100 */
272 *((u16 *)buf) = decpair[q];
276 * Call put_dec_full4 on x % 10000, return x / 10000.
277 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
278 * holds for all x < 1,128,869,999. The largest value this
279 * helper will ever be asked to convert is 1,125,520,955.
280 * (second call in the put_dec code, assuming n is all-ones).
282 static noinline_for_stack
283 unsigned put_dec_helper4(char *buf, unsigned x)
285 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
287 put_dec_full4(buf, x - q * 10000);
288 return q;
291 /* Based on code by Douglas W. Jones found at
292 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
293 * (with permission from the author).
294 * Performs no 64-bit division and hence should be fast on 32-bit machines.
296 static
297 char *put_dec(char *buf, unsigned long long n)
299 uint32_t d3, d2, d1, q, h;
301 if (n < 100*1000*1000)
302 return put_dec_trunc8(buf, n);
304 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
305 h = (n >> 32);
306 d2 = (h ) & 0xffff;
307 d3 = (h >> 16); /* implicit "& 0xffff" */
309 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
310 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
311 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
312 q = put_dec_helper4(buf, q);
314 q += 7671 * d3 + 9496 * d2 + 6 * d1;
315 q = put_dec_helper4(buf+4, q);
317 q += 4749 * d3 + 42 * d2;
318 q = put_dec_helper4(buf+8, q);
320 q += 281 * d3;
321 buf += 12;
322 if (q)
323 buf = put_dec_trunc8(buf, q);
324 else while (buf[-1] == '0')
325 --buf;
327 return buf;
330 #endif
333 * Convert passed number to decimal string.
334 * Returns the length of string. On buffer overflow, returns 0.
336 * If speed is not important, use snprintf(). It's easy to read the code.
338 int num_to_str(char *buf, int size, unsigned long long num)
340 /* put_dec requires 2-byte alignment of the buffer. */
341 char tmp[sizeof(num) * 3] __aligned(2);
342 int idx, len;
344 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
345 if (num <= 9) {
346 tmp[0] = '0' + num;
347 len = 1;
348 } else {
349 len = put_dec(tmp, num) - tmp;
352 if (len > size)
353 return 0;
354 for (idx = 0; idx < len; ++idx)
355 buf[idx] = tmp[len - idx - 1];
356 return len;
359 #define SIGN 1 /* unsigned/signed, must be 1 */
360 #define LEFT 2 /* left justified */
361 #define PLUS 4 /* show plus */
362 #define SPACE 8 /* space if plus */
363 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
364 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
365 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
367 enum format_type {
368 FORMAT_TYPE_NONE, /* Just a string part */
369 FORMAT_TYPE_WIDTH,
370 FORMAT_TYPE_PRECISION,
371 FORMAT_TYPE_CHAR,
372 FORMAT_TYPE_STR,
373 FORMAT_TYPE_PTR,
374 FORMAT_TYPE_PERCENT_CHAR,
375 FORMAT_TYPE_INVALID,
376 FORMAT_TYPE_LONG_LONG,
377 FORMAT_TYPE_ULONG,
378 FORMAT_TYPE_LONG,
379 FORMAT_TYPE_UBYTE,
380 FORMAT_TYPE_BYTE,
381 FORMAT_TYPE_USHORT,
382 FORMAT_TYPE_SHORT,
383 FORMAT_TYPE_UINT,
384 FORMAT_TYPE_INT,
385 FORMAT_TYPE_SIZE_T,
386 FORMAT_TYPE_PTRDIFF
389 struct printf_spec {
390 unsigned int type:8; /* format_type enum */
391 signed int field_width:24; /* width of output field */
392 unsigned int flags:8; /* flags to number() */
393 unsigned int base:8; /* number base, 8, 10 or 16 only */
394 signed int precision:16; /* # of digits/chars */
395 } __packed;
396 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
397 #define PRECISION_MAX ((1 << 15) - 1)
399 static noinline_for_stack
400 char *number(char *buf, char *end, unsigned long long num,
401 struct printf_spec spec)
403 /* put_dec requires 2-byte alignment of the buffer. */
404 char tmp[3 * sizeof(num)] __aligned(2);
405 char sign;
406 char locase;
407 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
408 int i;
409 bool is_zero = num == 0LL;
410 int field_width = spec.field_width;
411 int precision = spec.precision;
413 BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
415 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
416 * produces same digits or (maybe lowercased) letters */
417 locase = (spec.flags & SMALL);
418 if (spec.flags & LEFT)
419 spec.flags &= ~ZEROPAD;
420 sign = 0;
421 if (spec.flags & SIGN) {
422 if ((signed long long)num < 0) {
423 sign = '-';
424 num = -(signed long long)num;
425 field_width--;
426 } else if (spec.flags & PLUS) {
427 sign = '+';
428 field_width--;
429 } else if (spec.flags & SPACE) {
430 sign = ' ';
431 field_width--;
434 if (need_pfx) {
435 if (spec.base == 16)
436 field_width -= 2;
437 else if (!is_zero)
438 field_width--;
441 /* generate full string in tmp[], in reverse order */
442 i = 0;
443 if (num < spec.base)
444 tmp[i++] = hex_asc_upper[num] | locase;
445 else if (spec.base != 10) { /* 8 or 16 */
446 int mask = spec.base - 1;
447 int shift = 3;
449 if (spec.base == 16)
450 shift = 4;
451 do {
452 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
453 num >>= shift;
454 } while (num);
455 } else { /* base 10 */
456 i = put_dec(tmp, num) - tmp;
459 /* printing 100 using %2d gives "100", not "00" */
460 if (i > precision)
461 precision = i;
462 /* leading space padding */
463 field_width -= precision;
464 if (!(spec.flags & (ZEROPAD | LEFT))) {
465 while (--field_width >= 0) {
466 if (buf < end)
467 *buf = ' ';
468 ++buf;
471 /* sign */
472 if (sign) {
473 if (buf < end)
474 *buf = sign;
475 ++buf;
477 /* "0x" / "0" prefix */
478 if (need_pfx) {
479 if (spec.base == 16 || !is_zero) {
480 if (buf < end)
481 *buf = '0';
482 ++buf;
484 if (spec.base == 16) {
485 if (buf < end)
486 *buf = ('X' | locase);
487 ++buf;
490 /* zero or space padding */
491 if (!(spec.flags & LEFT)) {
492 char c = ' ' + (spec.flags & ZEROPAD);
493 BUILD_BUG_ON(' ' + ZEROPAD != '0');
494 while (--field_width >= 0) {
495 if (buf < end)
496 *buf = c;
497 ++buf;
500 /* hmm even more zero padding? */
501 while (i <= --precision) {
502 if (buf < end)
503 *buf = '0';
504 ++buf;
506 /* actual digits of result */
507 while (--i >= 0) {
508 if (buf < end)
509 *buf = tmp[i];
510 ++buf;
512 /* trailing space padding */
513 while (--field_width >= 0) {
514 if (buf < end)
515 *buf = ' ';
516 ++buf;
519 return buf;
522 static noinline_for_stack
523 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
525 struct printf_spec spec;
527 spec.type = FORMAT_TYPE_PTR;
528 spec.field_width = 2 + 2 * size; /* 0x + hex */
529 spec.flags = SPECIAL | SMALL | ZEROPAD;
530 spec.base = 16;
531 spec.precision = -1;
533 return number(buf, end, num, spec);
536 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
538 size_t size;
539 if (buf >= end) /* nowhere to put anything */
540 return;
541 size = end - buf;
542 if (size <= spaces) {
543 memset(buf, ' ', size);
544 return;
546 if (len) {
547 if (len > size - spaces)
548 len = size - spaces;
549 memmove(buf + spaces, buf, len);
551 memset(buf, ' ', spaces);
555 * Handle field width padding for a string.
556 * @buf: current buffer position
557 * @n: length of string
558 * @end: end of output buffer
559 * @spec: for field width and flags
560 * Returns: new buffer position after padding.
562 static noinline_for_stack
563 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
565 unsigned spaces;
567 if (likely(n >= spec.field_width))
568 return buf;
569 /* we want to pad the sucker */
570 spaces = spec.field_width - n;
571 if (!(spec.flags & LEFT)) {
572 move_right(buf - n, end, n, spaces);
573 return buf + spaces;
575 while (spaces--) {
576 if (buf < end)
577 *buf = ' ';
578 ++buf;
580 return buf;
583 static noinline_for_stack
584 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
586 int len = 0;
587 size_t lim = spec.precision;
589 if ((unsigned long)s < PAGE_SIZE)
590 s = "(null)";
592 while (lim--) {
593 char c = *s++;
594 if (!c)
595 break;
596 if (buf < end)
597 *buf = c;
598 ++buf;
599 ++len;
601 return widen_string(buf, len, end, spec);
604 static noinline_for_stack
605 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
606 const char *fmt)
608 const char *array[4], *s;
609 const struct dentry *p;
610 int depth;
611 int i, n;
613 switch (fmt[1]) {
614 case '2': case '3': case '4':
615 depth = fmt[1] - '0';
616 break;
617 default:
618 depth = 1;
621 rcu_read_lock();
622 for (i = 0; i < depth; i++, d = p) {
623 p = ACCESS_ONCE(d->d_parent);
624 array[i] = ACCESS_ONCE(d->d_name.name);
625 if (p == d) {
626 if (i)
627 array[i] = "";
628 i++;
629 break;
632 s = array[--i];
633 for (n = 0; n != spec.precision; n++, buf++) {
634 char c = *s++;
635 if (!c) {
636 if (!i)
637 break;
638 c = '/';
639 s = array[--i];
641 if (buf < end)
642 *buf = c;
644 rcu_read_unlock();
645 return widen_string(buf, n, end, spec);
648 #ifdef CONFIG_BLOCK
649 static noinline_for_stack
650 char *bdev_name(char *buf, char *end, struct block_device *bdev,
651 struct printf_spec spec, const char *fmt)
653 struct gendisk *hd = bdev->bd_disk;
655 buf = string(buf, end, hd->disk_name, spec);
656 if (bdev->bd_part->partno) {
657 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
658 if (buf < end)
659 *buf = 'p';
660 buf++;
662 buf = number(buf, end, bdev->bd_part->partno, spec);
664 return buf;
666 #endif
668 static noinline_for_stack
669 char *symbol_string(char *buf, char *end, void *ptr,
670 struct printf_spec spec, const char *fmt)
672 unsigned long value;
673 #ifdef CONFIG_KALLSYMS
674 char sym[KSYM_SYMBOL_LEN];
675 #endif
677 if (fmt[1] == 'R')
678 ptr = __builtin_extract_return_addr(ptr);
679 value = (unsigned long)ptr;
681 #ifdef CONFIG_KALLSYMS
682 if (*fmt == 'B')
683 sprint_backtrace(sym, value);
684 else if (*fmt != 'f' && *fmt != 's')
685 sprint_symbol(sym, value);
686 else
687 sprint_symbol_no_offset(sym, value);
689 return string(buf, end, sym, spec);
690 #else
691 return special_hex_number(buf, end, value, sizeof(void *));
692 #endif
695 static noinline_for_stack
696 char *resource_string(char *buf, char *end, struct resource *res,
697 struct printf_spec spec, const char *fmt)
699 #ifndef IO_RSRC_PRINTK_SIZE
700 #define IO_RSRC_PRINTK_SIZE 6
701 #endif
703 #ifndef MEM_RSRC_PRINTK_SIZE
704 #define MEM_RSRC_PRINTK_SIZE 10
705 #endif
706 static const struct printf_spec io_spec = {
707 .base = 16,
708 .field_width = IO_RSRC_PRINTK_SIZE,
709 .precision = -1,
710 .flags = SPECIAL | SMALL | ZEROPAD,
712 static const struct printf_spec mem_spec = {
713 .base = 16,
714 .field_width = MEM_RSRC_PRINTK_SIZE,
715 .precision = -1,
716 .flags = SPECIAL | SMALL | ZEROPAD,
718 static const struct printf_spec bus_spec = {
719 .base = 16,
720 .field_width = 2,
721 .precision = -1,
722 .flags = SMALL | ZEROPAD,
724 static const struct printf_spec dec_spec = {
725 .base = 10,
726 .precision = -1,
727 .flags = 0,
729 static const struct printf_spec str_spec = {
730 .field_width = -1,
731 .precision = 10,
732 .flags = LEFT,
734 static const struct printf_spec flag_spec = {
735 .base = 16,
736 .precision = -1,
737 .flags = SPECIAL | SMALL,
740 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
741 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
742 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
743 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
744 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
745 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
746 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
747 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
749 char *p = sym, *pend = sym + sizeof(sym);
750 int decode = (fmt[0] == 'R') ? 1 : 0;
751 const struct printf_spec *specp;
753 *p++ = '[';
754 if (res->flags & IORESOURCE_IO) {
755 p = string(p, pend, "io ", str_spec);
756 specp = &io_spec;
757 } else if (res->flags & IORESOURCE_MEM) {
758 p = string(p, pend, "mem ", str_spec);
759 specp = &mem_spec;
760 } else if (res->flags & IORESOURCE_IRQ) {
761 p = string(p, pend, "irq ", str_spec);
762 specp = &dec_spec;
763 } else if (res->flags & IORESOURCE_DMA) {
764 p = string(p, pend, "dma ", str_spec);
765 specp = &dec_spec;
766 } else if (res->flags & IORESOURCE_BUS) {
767 p = string(p, pend, "bus ", str_spec);
768 specp = &bus_spec;
769 } else {
770 p = string(p, pend, "??? ", str_spec);
771 specp = &mem_spec;
772 decode = 0;
774 if (decode && res->flags & IORESOURCE_UNSET) {
775 p = string(p, pend, "size ", str_spec);
776 p = number(p, pend, resource_size(res), *specp);
777 } else {
778 p = number(p, pend, res->start, *specp);
779 if (res->start != res->end) {
780 *p++ = '-';
781 p = number(p, pend, res->end, *specp);
784 if (decode) {
785 if (res->flags & IORESOURCE_MEM_64)
786 p = string(p, pend, " 64bit", str_spec);
787 if (res->flags & IORESOURCE_PREFETCH)
788 p = string(p, pend, " pref", str_spec);
789 if (res->flags & IORESOURCE_WINDOW)
790 p = string(p, pend, " window", str_spec);
791 if (res->flags & IORESOURCE_DISABLED)
792 p = string(p, pend, " disabled", str_spec);
793 } else {
794 p = string(p, pend, " flags ", str_spec);
795 p = number(p, pend, res->flags, flag_spec);
797 *p++ = ']';
798 *p = '\0';
800 return string(buf, end, sym, spec);
803 static noinline_for_stack
804 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
805 const char *fmt)
807 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
808 negative value, fallback to the default */
809 char separator;
811 if (spec.field_width == 0)
812 /* nothing to print */
813 return buf;
815 if (ZERO_OR_NULL_PTR(addr))
816 /* NULL pointer */
817 return string(buf, end, NULL, spec);
819 switch (fmt[1]) {
820 case 'C':
821 separator = ':';
822 break;
823 case 'D':
824 separator = '-';
825 break;
826 case 'N':
827 separator = 0;
828 break;
829 default:
830 separator = ' ';
831 break;
834 if (spec.field_width > 0)
835 len = min_t(int, spec.field_width, 64);
837 for (i = 0; i < len; ++i) {
838 if (buf < end)
839 *buf = hex_asc_hi(addr[i]);
840 ++buf;
841 if (buf < end)
842 *buf = hex_asc_lo(addr[i]);
843 ++buf;
845 if (separator && i != len - 1) {
846 if (buf < end)
847 *buf = separator;
848 ++buf;
852 return buf;
855 static noinline_for_stack
856 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
857 struct printf_spec spec, const char *fmt)
859 const int CHUNKSZ = 32;
860 int nr_bits = max_t(int, spec.field_width, 0);
861 int i, chunksz;
862 bool first = true;
864 /* reused to print numbers */
865 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
867 chunksz = nr_bits & (CHUNKSZ - 1);
868 if (chunksz == 0)
869 chunksz = CHUNKSZ;
871 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
872 for (; i >= 0; i -= CHUNKSZ) {
873 u32 chunkmask, val;
874 int word, bit;
876 chunkmask = ((1ULL << chunksz) - 1);
877 word = i / BITS_PER_LONG;
878 bit = i % BITS_PER_LONG;
879 val = (bitmap[word] >> bit) & chunkmask;
881 if (!first) {
882 if (buf < end)
883 *buf = ',';
884 buf++;
886 first = false;
888 spec.field_width = DIV_ROUND_UP(chunksz, 4);
889 buf = number(buf, end, val, spec);
891 chunksz = CHUNKSZ;
893 return buf;
896 static noinline_for_stack
897 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
898 struct printf_spec spec, const char *fmt)
900 int nr_bits = max_t(int, spec.field_width, 0);
901 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
902 int cur, rbot, rtop;
903 bool first = true;
905 /* reused to print numbers */
906 spec = (struct printf_spec){ .base = 10 };
908 rbot = cur = find_first_bit(bitmap, nr_bits);
909 while (cur < nr_bits) {
910 rtop = cur;
911 cur = find_next_bit(bitmap, nr_bits, cur + 1);
912 if (cur < nr_bits && cur <= rtop + 1)
913 continue;
915 if (!first) {
916 if (buf < end)
917 *buf = ',';
918 buf++;
920 first = false;
922 buf = number(buf, end, rbot, spec);
923 if (rbot < rtop) {
924 if (buf < end)
925 *buf = '-';
926 buf++;
928 buf = number(buf, end, rtop, spec);
931 rbot = cur;
933 return buf;
936 static noinline_for_stack
937 char *mac_address_string(char *buf, char *end, u8 *addr,
938 struct printf_spec spec, const char *fmt)
940 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
941 char *p = mac_addr;
942 int i;
943 char separator;
944 bool reversed = false;
946 switch (fmt[1]) {
947 case 'F':
948 separator = '-';
949 break;
951 case 'R':
952 reversed = true;
953 /* fall through */
955 default:
956 separator = ':';
957 break;
960 for (i = 0; i < 6; i++) {
961 if (reversed)
962 p = hex_byte_pack(p, addr[5 - i]);
963 else
964 p = hex_byte_pack(p, addr[i]);
966 if (fmt[0] == 'M' && i != 5)
967 *p++ = separator;
969 *p = '\0';
971 return string(buf, end, mac_addr, spec);
974 static noinline_for_stack
975 char *ip4_string(char *p, const u8 *addr, const char *fmt)
977 int i;
978 bool leading_zeros = (fmt[0] == 'i');
979 int index;
980 int step;
982 switch (fmt[2]) {
983 case 'h':
984 #ifdef __BIG_ENDIAN
985 index = 0;
986 step = 1;
987 #else
988 index = 3;
989 step = -1;
990 #endif
991 break;
992 case 'l':
993 index = 3;
994 step = -1;
995 break;
996 case 'n':
997 case 'b':
998 default:
999 index = 0;
1000 step = 1;
1001 break;
1003 for (i = 0; i < 4; i++) {
1004 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1005 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1006 if (leading_zeros) {
1007 if (digits < 3)
1008 *p++ = '0';
1009 if (digits < 2)
1010 *p++ = '0';
1012 /* reverse the digits in the quad */
1013 while (digits--)
1014 *p++ = temp[digits];
1015 if (i < 3)
1016 *p++ = '.';
1017 index += step;
1019 *p = '\0';
1021 return p;
1024 static noinline_for_stack
1025 char *ip6_compressed_string(char *p, const char *addr)
1027 int i, j, range;
1028 unsigned char zerolength[8];
1029 int longest = 1;
1030 int colonpos = -1;
1031 u16 word;
1032 u8 hi, lo;
1033 bool needcolon = false;
1034 bool useIPv4;
1035 struct in6_addr in6;
1037 memcpy(&in6, addr, sizeof(struct in6_addr));
1039 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1041 memset(zerolength, 0, sizeof(zerolength));
1043 if (useIPv4)
1044 range = 6;
1045 else
1046 range = 8;
1048 /* find position of longest 0 run */
1049 for (i = 0; i < range; i++) {
1050 for (j = i; j < range; j++) {
1051 if (in6.s6_addr16[j] != 0)
1052 break;
1053 zerolength[i]++;
1056 for (i = 0; i < range; i++) {
1057 if (zerolength[i] > longest) {
1058 longest = zerolength[i];
1059 colonpos = i;
1062 if (longest == 1) /* don't compress a single 0 */
1063 colonpos = -1;
1065 /* emit address */
1066 for (i = 0; i < range; i++) {
1067 if (i == colonpos) {
1068 if (needcolon || i == 0)
1069 *p++ = ':';
1070 *p++ = ':';
1071 needcolon = false;
1072 i += longest - 1;
1073 continue;
1075 if (needcolon) {
1076 *p++ = ':';
1077 needcolon = false;
1079 /* hex u16 without leading 0s */
1080 word = ntohs(in6.s6_addr16[i]);
1081 hi = word >> 8;
1082 lo = word & 0xff;
1083 if (hi) {
1084 if (hi > 0x0f)
1085 p = hex_byte_pack(p, hi);
1086 else
1087 *p++ = hex_asc_lo(hi);
1088 p = hex_byte_pack(p, lo);
1090 else if (lo > 0x0f)
1091 p = hex_byte_pack(p, lo);
1092 else
1093 *p++ = hex_asc_lo(lo);
1094 needcolon = true;
1097 if (useIPv4) {
1098 if (needcolon)
1099 *p++ = ':';
1100 p = ip4_string(p, &in6.s6_addr[12], "I4");
1102 *p = '\0';
1104 return p;
1107 static noinline_for_stack
1108 char *ip6_string(char *p, const char *addr, const char *fmt)
1110 int i;
1112 for (i = 0; i < 8; i++) {
1113 p = hex_byte_pack(p, *addr++);
1114 p = hex_byte_pack(p, *addr++);
1115 if (fmt[0] == 'I' && i != 7)
1116 *p++ = ':';
1118 *p = '\0';
1120 return p;
1123 static noinline_for_stack
1124 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1125 struct printf_spec spec, const char *fmt)
1127 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1129 if (fmt[0] == 'I' && fmt[2] == 'c')
1130 ip6_compressed_string(ip6_addr, addr);
1131 else
1132 ip6_string(ip6_addr, addr, fmt);
1134 return string(buf, end, ip6_addr, spec);
1137 static noinline_for_stack
1138 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1139 struct printf_spec spec, const char *fmt)
1141 char ip4_addr[sizeof("255.255.255.255")];
1143 ip4_string(ip4_addr, addr, fmt);
1145 return string(buf, end, ip4_addr, spec);
1148 static noinline_for_stack
1149 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1150 struct printf_spec spec, const char *fmt)
1152 bool have_p = false, have_s = false, have_f = false, have_c = false;
1153 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1154 sizeof(":12345") + sizeof("/123456789") +
1155 sizeof("%1234567890")];
1156 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1157 const u8 *addr = (const u8 *) &sa->sin6_addr;
1158 char fmt6[2] = { fmt[0], '6' };
1159 u8 off = 0;
1161 fmt++;
1162 while (isalpha(*++fmt)) {
1163 switch (*fmt) {
1164 case 'p':
1165 have_p = true;
1166 break;
1167 case 'f':
1168 have_f = true;
1169 break;
1170 case 's':
1171 have_s = true;
1172 break;
1173 case 'c':
1174 have_c = true;
1175 break;
1179 if (have_p || have_s || have_f) {
1180 *p = '[';
1181 off = 1;
1184 if (fmt6[0] == 'I' && have_c)
1185 p = ip6_compressed_string(ip6_addr + off, addr);
1186 else
1187 p = ip6_string(ip6_addr + off, addr, fmt6);
1189 if (have_p || have_s || have_f)
1190 *p++ = ']';
1192 if (have_p) {
1193 *p++ = ':';
1194 p = number(p, pend, ntohs(sa->sin6_port), spec);
1196 if (have_f) {
1197 *p++ = '/';
1198 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1199 IPV6_FLOWINFO_MASK), spec);
1201 if (have_s) {
1202 *p++ = '%';
1203 p = number(p, pend, sa->sin6_scope_id, spec);
1205 *p = '\0';
1207 return string(buf, end, ip6_addr, spec);
1210 static noinline_for_stack
1211 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1212 struct printf_spec spec, const char *fmt)
1214 bool have_p = false;
1215 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1216 char *pend = ip4_addr + sizeof(ip4_addr);
1217 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1218 char fmt4[3] = { fmt[0], '4', 0 };
1220 fmt++;
1221 while (isalpha(*++fmt)) {
1222 switch (*fmt) {
1223 case 'p':
1224 have_p = true;
1225 break;
1226 case 'h':
1227 case 'l':
1228 case 'n':
1229 case 'b':
1230 fmt4[2] = *fmt;
1231 break;
1235 p = ip4_string(ip4_addr, addr, fmt4);
1236 if (have_p) {
1237 *p++ = ':';
1238 p = number(p, pend, ntohs(sa->sin_port), spec);
1240 *p = '\0';
1242 return string(buf, end, ip4_addr, spec);
1245 static noinline_for_stack
1246 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1247 const char *fmt)
1249 bool found = true;
1250 int count = 1;
1251 unsigned int flags = 0;
1252 int len;
1254 if (spec.field_width == 0)
1255 return buf; /* nothing to print */
1257 if (ZERO_OR_NULL_PTR(addr))
1258 return string(buf, end, NULL, spec); /* NULL pointer */
1261 do {
1262 switch (fmt[count++]) {
1263 case 'a':
1264 flags |= ESCAPE_ANY;
1265 break;
1266 case 'c':
1267 flags |= ESCAPE_SPECIAL;
1268 break;
1269 case 'h':
1270 flags |= ESCAPE_HEX;
1271 break;
1272 case 'n':
1273 flags |= ESCAPE_NULL;
1274 break;
1275 case 'o':
1276 flags |= ESCAPE_OCTAL;
1277 break;
1278 case 'p':
1279 flags |= ESCAPE_NP;
1280 break;
1281 case 's':
1282 flags |= ESCAPE_SPACE;
1283 break;
1284 default:
1285 found = false;
1286 break;
1288 } while (found);
1290 if (!flags)
1291 flags = ESCAPE_ANY_NP;
1293 len = spec.field_width < 0 ? 1 : spec.field_width;
1296 * string_escape_mem() writes as many characters as it can to
1297 * the given buffer, and returns the total size of the output
1298 * had the buffer been big enough.
1300 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1302 return buf;
1305 static noinline_for_stack
1306 char *uuid_string(char *buf, char *end, const u8 *addr,
1307 struct printf_spec spec, const char *fmt)
1309 char uuid[UUID_STRING_LEN + 1];
1310 char *p = uuid;
1311 int i;
1312 const u8 *index = uuid_index;
1313 bool uc = false;
1315 switch (*(++fmt)) {
1316 case 'L':
1317 uc = true; /* fall-through */
1318 case 'l':
1319 index = guid_index;
1320 break;
1321 case 'B':
1322 uc = true;
1323 break;
1326 for (i = 0; i < 16; i++) {
1327 if (uc)
1328 p = hex_byte_pack_upper(p, addr[index[i]]);
1329 else
1330 p = hex_byte_pack(p, addr[index[i]]);
1331 switch (i) {
1332 case 3:
1333 case 5:
1334 case 7:
1335 case 9:
1336 *p++ = '-';
1337 break;
1341 *p = 0;
1343 return string(buf, end, uuid, spec);
1346 static noinline_for_stack
1347 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1349 unsigned long long num;
1350 int size;
1352 switch (fmt[1]) {
1353 case 'F':
1354 num = *(const netdev_features_t *)addr;
1355 size = sizeof(netdev_features_t);
1356 break;
1357 default:
1358 num = (unsigned long)addr;
1359 size = sizeof(unsigned long);
1360 break;
1363 return special_hex_number(buf, end, num, size);
1366 static noinline_for_stack
1367 char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1369 unsigned long long num;
1370 int size;
1372 switch (fmt[1]) {
1373 case 'd':
1374 num = *(const dma_addr_t *)addr;
1375 size = sizeof(dma_addr_t);
1376 break;
1377 case 'p':
1378 default:
1379 num = *(const phys_addr_t *)addr;
1380 size = sizeof(phys_addr_t);
1381 break;
1384 return special_hex_number(buf, end, num, size);
1387 static noinline_for_stack
1388 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1389 const char *fmt)
1391 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1392 return string(buf, end, NULL, spec);
1394 switch (fmt[1]) {
1395 case 'r':
1396 return number(buf, end, clk_get_rate(clk), spec);
1398 case 'n':
1399 default:
1400 #ifdef CONFIG_COMMON_CLK
1401 return string(buf, end, __clk_get_name(clk), spec);
1402 #else
1403 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1404 #endif
1408 static
1409 char *format_flags(char *buf, char *end, unsigned long flags,
1410 const struct trace_print_flags *names)
1412 unsigned long mask;
1413 const struct printf_spec strspec = {
1414 .field_width = -1,
1415 .precision = -1,
1417 const struct printf_spec numspec = {
1418 .flags = SPECIAL|SMALL,
1419 .field_width = -1,
1420 .precision = -1,
1421 .base = 16,
1424 for ( ; flags && names->name; names++) {
1425 mask = names->mask;
1426 if ((flags & mask) != mask)
1427 continue;
1429 buf = string(buf, end, names->name, strspec);
1431 flags &= ~mask;
1432 if (flags) {
1433 if (buf < end)
1434 *buf = '|';
1435 buf++;
1439 if (flags)
1440 buf = number(buf, end, flags, numspec);
1442 return buf;
1445 static noinline_for_stack
1446 char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1448 unsigned long flags;
1449 const struct trace_print_flags *names;
1451 switch (fmt[1]) {
1452 case 'p':
1453 flags = *(unsigned long *)flags_ptr;
1454 /* Remove zone id */
1455 flags &= (1UL << NR_PAGEFLAGS) - 1;
1456 names = pageflag_names;
1457 break;
1458 case 'v':
1459 flags = *(unsigned long *)flags_ptr;
1460 names = vmaflag_names;
1461 break;
1462 case 'g':
1463 flags = *(gfp_t *)flags_ptr;
1464 names = gfpflag_names;
1465 break;
1466 default:
1467 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1468 return buf;
1471 return format_flags(buf, end, flags, names);
1474 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1476 for ( ; np && depth; depth--)
1477 np = np->parent;
1479 return kbasename(np->full_name);
1482 static noinline_for_stack
1483 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1485 int depth;
1486 const struct device_node *parent = np->parent;
1487 static const struct printf_spec strspec = {
1488 .field_width = -1,
1489 .precision = -1,
1492 /* special case for root node */
1493 if (!parent)
1494 return string(buf, end, "/", strspec);
1496 for (depth = 0; parent->parent; depth++)
1497 parent = parent->parent;
1499 for ( ; depth >= 0; depth--) {
1500 buf = string(buf, end, "/", strspec);
1501 buf = string(buf, end, device_node_name_for_depth(np, depth),
1502 strspec);
1504 return buf;
1507 static noinline_for_stack
1508 char *device_node_string(char *buf, char *end, struct device_node *dn,
1509 struct printf_spec spec, const char *fmt)
1511 char tbuf[sizeof("xxxx") + 1];
1512 const char *p;
1513 int ret;
1514 char *buf_start = buf;
1515 struct property *prop;
1516 bool has_mult, pass;
1517 static const struct printf_spec num_spec = {
1518 .flags = SMALL,
1519 .field_width = -1,
1520 .precision = -1,
1521 .base = 10,
1524 struct printf_spec str_spec = spec;
1525 str_spec.field_width = -1;
1527 if (!IS_ENABLED(CONFIG_OF))
1528 return string(buf, end, "(!OF)", spec);
1530 if ((unsigned long)dn < PAGE_SIZE)
1531 return string(buf, end, "(null)", spec);
1533 /* simple case without anything any more format specifiers */
1534 fmt++;
1535 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1536 fmt = "f";
1538 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1539 if (pass) {
1540 if (buf < end)
1541 *buf = ':';
1542 buf++;
1545 switch (*fmt) {
1546 case 'f': /* full_name */
1547 buf = device_node_gen_full_name(dn, buf, end);
1548 break;
1549 case 'n': /* name */
1550 buf = string(buf, end, dn->name, str_spec);
1551 break;
1552 case 'p': /* phandle */
1553 buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1554 break;
1555 case 'P': /* path-spec */
1556 p = kbasename(of_node_full_name(dn));
1557 if (!p[1])
1558 p = "/";
1559 buf = string(buf, end, p, str_spec);
1560 break;
1561 case 'F': /* flags */
1562 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1563 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1564 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1565 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1566 tbuf[4] = 0;
1567 buf = string(buf, end, tbuf, str_spec);
1568 break;
1569 case 'c': /* major compatible string */
1570 ret = of_property_read_string(dn, "compatible", &p);
1571 if (!ret)
1572 buf = string(buf, end, p, str_spec);
1573 break;
1574 case 'C': /* full compatible string */
1575 has_mult = false;
1576 of_property_for_each_string(dn, "compatible", prop, p) {
1577 if (has_mult)
1578 buf = string(buf, end, ",", str_spec);
1579 buf = string(buf, end, "\"", str_spec);
1580 buf = string(buf, end, p, str_spec);
1581 buf = string(buf, end, "\"", str_spec);
1583 has_mult = true;
1585 break;
1586 default:
1587 break;
1591 return widen_string(buf, buf - buf_start, end, spec);
1594 int kptr_restrict __read_mostly;
1597 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1598 * by an extra set of alphanumeric characters that are extended format
1599 * specifiers.
1601 * Please update scripts/checkpatch.pl when adding/removing conversion
1602 * characters. (Search for "check for vsprintf extension").
1604 * Right now we handle:
1606 * - 'F' For symbolic function descriptor pointers with offset
1607 * - 'f' For simple symbolic function names without offset
1608 * - 'S' For symbolic direct pointers with offset
1609 * - 's' For symbolic direct pointers without offset
1610 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1611 * - 'B' For backtraced symbolic direct pointers with offset
1612 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1613 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1614 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1615 * width which must be explicitly specified either as part of the
1616 * format string '%32b[l]' or through '%*b[l]', [l] selects
1617 * range-list format instead of hex format
1618 * - 'M' For a 6-byte MAC address, it prints the address in the
1619 * usual colon-separated hex notation
1620 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1621 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1622 * with a dash-separated hex notation
1623 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1624 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1625 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1626 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1627 * [S][pfs]
1628 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1629 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1630 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1631 * IPv6 omits the colons (01020304...0f)
1632 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1633 * [S][pfs]
1634 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1635 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1636 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1637 * - 'I[6S]c' for IPv6 addresses printed as specified by
1638 * http://tools.ietf.org/html/rfc5952
1639 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1640 * of the following flags (see string_escape_mem() for the
1641 * details):
1642 * a - ESCAPE_ANY
1643 * c - ESCAPE_SPECIAL
1644 * h - ESCAPE_HEX
1645 * n - ESCAPE_NULL
1646 * o - ESCAPE_OCTAL
1647 * p - ESCAPE_NP
1648 * s - ESCAPE_SPACE
1649 * By default ESCAPE_ANY_NP is used.
1650 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1651 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1652 * Options for %pU are:
1653 * b big endian lower case hex (default)
1654 * B big endian UPPER case hex
1655 * l little endian lower case hex
1656 * L little endian UPPER case hex
1657 * big endian output byte order is:
1658 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1659 * little endian output byte order is:
1660 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1661 * - 'V' For a struct va_format which contains a format string * and va_list *,
1662 * call vsnprintf(->format, *->va_list).
1663 * Implements a "recursive vsnprintf".
1664 * Do not use this feature without some mechanism to verify the
1665 * correctness of the format string and va_list arguments.
1666 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1667 * - 'NF' For a netdev_features_t
1668 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1669 * a certain separator (' ' by default):
1670 * C colon
1671 * D dash
1672 * N no separator
1673 * The maximum supported length is 64 bytes of the input. Consider
1674 * to use print_hex_dump() for the larger input.
1675 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1676 * (default assumed to be phys_addr_t, passed by reference)
1677 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1678 * - 'D[234]' Same as 'd' but for a struct file
1679 * - 'g' For block_device name (gendisk + partition number)
1680 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1681 * (legacy clock framework) of the clock
1682 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1683 * (legacy clock framework) of the clock
1684 * - 'Cr' For a clock, it prints the current rate of the clock
1685 * - 'G' For flags to be printed as a collection of symbolic strings that would
1686 * construct the specific value. Supported flags given by option:
1687 * p page flags (see struct page) given as pointer to unsigned long
1688 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1689 * v vma flags (VM_*) given as pointer to unsigned long
1690 * - 'O' For a kobject based struct. Must be one of the following:
1691 * - 'OF[fnpPcCF]' For a device tree object
1692 * Without any optional arguments prints the full_name
1693 * f device node full_name
1694 * n device node name
1695 * p device node phandle
1696 * P device node path spec (name + @unit)
1697 * F device node flags
1698 * c major compatible string
1699 * C full compatible string
1701 * ** Please update also Documentation/printk-formats.txt when making changes **
1703 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1704 * function pointers are really function descriptors, which contain a
1705 * pointer to the real address.
1707 static noinline_for_stack
1708 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1709 struct printf_spec spec)
1711 const int default_width = 2 * sizeof(void *);
1713 if (!ptr && *fmt != 'K') {
1715 * Print (null) with the same width as a pointer so it makes
1716 * tabular output look nice.
1718 if (spec.field_width == -1)
1719 spec.field_width = default_width;
1720 return string(buf, end, "(null)", spec);
1723 switch (*fmt) {
1724 case 'F':
1725 case 'f':
1726 ptr = dereference_function_descriptor(ptr);
1727 /* Fallthrough */
1728 case 'S':
1729 case 's':
1730 case 'B':
1731 return symbol_string(buf, end, ptr, spec, fmt);
1732 case 'R':
1733 case 'r':
1734 return resource_string(buf, end, ptr, spec, fmt);
1735 case 'h':
1736 return hex_string(buf, end, ptr, spec, fmt);
1737 case 'b':
1738 switch (fmt[1]) {
1739 case 'l':
1740 return bitmap_list_string(buf, end, ptr, spec, fmt);
1741 default:
1742 return bitmap_string(buf, end, ptr, spec, fmt);
1744 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1745 case 'm': /* Contiguous: 000102030405 */
1746 /* [mM]F (FDDI) */
1747 /* [mM]R (Reverse order; Bluetooth) */
1748 return mac_address_string(buf, end, ptr, spec, fmt);
1749 case 'I': /* Formatted IP supported
1750 * 4: 1.2.3.4
1751 * 6: 0001:0203:...:0708
1752 * 6c: 1::708 or 1::1.2.3.4
1754 case 'i': /* Contiguous:
1755 * 4: 001.002.003.004
1756 * 6: 000102...0f
1758 switch (fmt[1]) {
1759 case '6':
1760 return ip6_addr_string(buf, end, ptr, spec, fmt);
1761 case '4':
1762 return ip4_addr_string(buf, end, ptr, spec, fmt);
1763 case 'S': {
1764 const union {
1765 struct sockaddr raw;
1766 struct sockaddr_in v4;
1767 struct sockaddr_in6 v6;
1768 } *sa = ptr;
1770 switch (sa->raw.sa_family) {
1771 case AF_INET:
1772 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1773 case AF_INET6:
1774 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1775 default:
1776 return string(buf, end, "(invalid address)", spec);
1779 break;
1780 case 'E':
1781 return escaped_string(buf, end, ptr, spec, fmt);
1782 case 'U':
1783 return uuid_string(buf, end, ptr, spec, fmt);
1784 case 'V':
1786 va_list va;
1788 va_copy(va, *((struct va_format *)ptr)->va);
1789 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1790 ((struct va_format *)ptr)->fmt, va);
1791 va_end(va);
1792 return buf;
1794 case 'K':
1795 switch (kptr_restrict) {
1796 case 0:
1797 /* Always print %pK values */
1798 break;
1799 case 1: {
1800 const struct cred *cred;
1803 * kptr_restrict==1 cannot be used in IRQ context
1804 * because its test for CAP_SYSLOG would be meaningless.
1806 if (in_irq() || in_serving_softirq() || in_nmi()) {
1807 if (spec.field_width == -1)
1808 spec.field_width = default_width;
1809 return string(buf, end, "pK-error", spec);
1813 * Only print the real pointer value if the current
1814 * process has CAP_SYSLOG and is running with the
1815 * same credentials it started with. This is because
1816 * access to files is checked at open() time, but %pK
1817 * checks permission at read() time. We don't want to
1818 * leak pointer values if a binary opens a file using
1819 * %pK and then elevates privileges before reading it.
1821 cred = current_cred();
1822 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1823 !uid_eq(cred->euid, cred->uid) ||
1824 !gid_eq(cred->egid, cred->gid))
1825 ptr = NULL;
1826 break;
1828 case 2:
1829 default:
1830 /* Always print 0's for %pK */
1831 ptr = NULL;
1832 break;
1834 break;
1836 case 'N':
1837 return netdev_bits(buf, end, ptr, fmt);
1838 case 'a':
1839 return address_val(buf, end, ptr, fmt);
1840 case 'd':
1841 return dentry_name(buf, end, ptr, spec, fmt);
1842 case 'C':
1843 return clock(buf, end, ptr, spec, fmt);
1844 case 'D':
1845 return dentry_name(buf, end,
1846 ((const struct file *)ptr)->f_path.dentry,
1847 spec, fmt);
1848 #ifdef CONFIG_BLOCK
1849 case 'g':
1850 return bdev_name(buf, end, ptr, spec, fmt);
1851 #endif
1853 case 'G':
1854 return flags_string(buf, end, ptr, fmt);
1855 case 'O':
1856 switch (fmt[1]) {
1857 case 'F':
1858 return device_node_string(buf, end, ptr, spec, fmt + 1);
1861 spec.flags |= SMALL;
1862 if (spec.field_width == -1) {
1863 spec.field_width = default_width;
1864 spec.flags |= ZEROPAD;
1866 spec.base = 16;
1868 return number(buf, end, (unsigned long) ptr, spec);
1872 * Helper function to decode printf style format.
1873 * Each call decode a token from the format and return the
1874 * number of characters read (or likely the delta where it wants
1875 * to go on the next call).
1876 * The decoded token is returned through the parameters
1878 * 'h', 'l', or 'L' for integer fields
1879 * 'z' support added 23/7/1999 S.H.
1880 * 'z' changed to 'Z' --davidm 1/25/99
1881 * 'Z' changed to 'z' --adobriyan 2017-01-25
1882 * 't' added for ptrdiff_t
1884 * @fmt: the format string
1885 * @type of the token returned
1886 * @flags: various flags such as +, -, # tokens..
1887 * @field_width: overwritten width
1888 * @base: base of the number (octal, hex, ...)
1889 * @precision: precision of a number
1890 * @qualifier: qualifier of a number (long, size_t, ...)
1892 static noinline_for_stack
1893 int format_decode(const char *fmt, struct printf_spec *spec)
1895 const char *start = fmt;
1896 char qualifier;
1898 /* we finished early by reading the field width */
1899 if (spec->type == FORMAT_TYPE_WIDTH) {
1900 if (spec->field_width < 0) {
1901 spec->field_width = -spec->field_width;
1902 spec->flags |= LEFT;
1904 spec->type = FORMAT_TYPE_NONE;
1905 goto precision;
1908 /* we finished early by reading the precision */
1909 if (spec->type == FORMAT_TYPE_PRECISION) {
1910 if (spec->precision < 0)
1911 spec->precision = 0;
1913 spec->type = FORMAT_TYPE_NONE;
1914 goto qualifier;
1917 /* By default */
1918 spec->type = FORMAT_TYPE_NONE;
1920 for (; *fmt ; ++fmt) {
1921 if (*fmt == '%')
1922 break;
1925 /* Return the current non-format string */
1926 if (fmt != start || !*fmt)
1927 return fmt - start;
1929 /* Process flags */
1930 spec->flags = 0;
1932 while (1) { /* this also skips first '%' */
1933 bool found = true;
1935 ++fmt;
1937 switch (*fmt) {
1938 case '-': spec->flags |= LEFT; break;
1939 case '+': spec->flags |= PLUS; break;
1940 case ' ': spec->flags |= SPACE; break;
1941 case '#': spec->flags |= SPECIAL; break;
1942 case '0': spec->flags |= ZEROPAD; break;
1943 default: found = false;
1946 if (!found)
1947 break;
1950 /* get field width */
1951 spec->field_width = -1;
1953 if (isdigit(*fmt))
1954 spec->field_width = skip_atoi(&fmt);
1955 else if (*fmt == '*') {
1956 /* it's the next argument */
1957 spec->type = FORMAT_TYPE_WIDTH;
1958 return ++fmt - start;
1961 precision:
1962 /* get the precision */
1963 spec->precision = -1;
1964 if (*fmt == '.') {
1965 ++fmt;
1966 if (isdigit(*fmt)) {
1967 spec->precision = skip_atoi(&fmt);
1968 if (spec->precision < 0)
1969 spec->precision = 0;
1970 } else if (*fmt == '*') {
1971 /* it's the next argument */
1972 spec->type = FORMAT_TYPE_PRECISION;
1973 return ++fmt - start;
1977 qualifier:
1978 /* get the conversion qualifier */
1979 qualifier = 0;
1980 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1981 *fmt == 'z' || *fmt == 't') {
1982 qualifier = *fmt++;
1983 if (unlikely(qualifier == *fmt)) {
1984 if (qualifier == 'l') {
1985 qualifier = 'L';
1986 ++fmt;
1987 } else if (qualifier == 'h') {
1988 qualifier = 'H';
1989 ++fmt;
1994 /* default base */
1995 spec->base = 10;
1996 switch (*fmt) {
1997 case 'c':
1998 spec->type = FORMAT_TYPE_CHAR;
1999 return ++fmt - start;
2001 case 's':
2002 spec->type = FORMAT_TYPE_STR;
2003 return ++fmt - start;
2005 case 'p':
2006 spec->type = FORMAT_TYPE_PTR;
2007 return ++fmt - start;
2009 case '%':
2010 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2011 return ++fmt - start;
2013 /* integer number formats - set up the flags and "break" */
2014 case 'o':
2015 spec->base = 8;
2016 break;
2018 case 'x':
2019 spec->flags |= SMALL;
2021 case 'X':
2022 spec->base = 16;
2023 break;
2025 case 'd':
2026 case 'i':
2027 spec->flags |= SIGN;
2028 case 'u':
2029 break;
2031 case 'n':
2033 * Since %n poses a greater security risk than
2034 * utility, treat it as any other invalid or
2035 * unsupported format specifier.
2037 /* Fall-through */
2039 default:
2040 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2041 spec->type = FORMAT_TYPE_INVALID;
2042 return fmt - start;
2045 if (qualifier == 'L')
2046 spec->type = FORMAT_TYPE_LONG_LONG;
2047 else if (qualifier == 'l') {
2048 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2049 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2050 } else if (qualifier == 'z') {
2051 spec->type = FORMAT_TYPE_SIZE_T;
2052 } else if (qualifier == 't') {
2053 spec->type = FORMAT_TYPE_PTRDIFF;
2054 } else if (qualifier == 'H') {
2055 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2056 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2057 } else if (qualifier == 'h') {
2058 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2059 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2060 } else {
2061 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2062 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2065 return ++fmt - start;
2068 static void
2069 set_field_width(struct printf_spec *spec, int width)
2071 spec->field_width = width;
2072 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2073 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2077 static void
2078 set_precision(struct printf_spec *spec, int prec)
2080 spec->precision = prec;
2081 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2082 spec->precision = clamp(prec, 0, PRECISION_MAX);
2087 * vsnprintf - Format a string and place it in a buffer
2088 * @buf: The buffer to place the result into
2089 * @size: The size of the buffer, including the trailing null space
2090 * @fmt: The format string to use
2091 * @args: Arguments for the format string
2093 * This function generally follows C99 vsnprintf, but has some
2094 * extensions and a few limitations:
2096 * - ``%n`` is unsupported
2097 * - ``%p*`` is handled by pointer()
2099 * See pointer() or Documentation/printk-formats.txt for more
2100 * extensive description.
2102 * **Please update the documentation in both places when making changes**
2104 * The return value is the number of characters which would
2105 * be generated for the given input, excluding the trailing
2106 * '\0', as per ISO C99. If you want to have the exact
2107 * number of characters written into @buf as return value
2108 * (not including the trailing '\0'), use vscnprintf(). If the
2109 * return is greater than or equal to @size, the resulting
2110 * string is truncated.
2112 * If you're not already dealing with a va_list consider using snprintf().
2114 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2116 unsigned long long num;
2117 char *str, *end;
2118 struct printf_spec spec = {0};
2120 /* Reject out-of-range values early. Large positive sizes are
2121 used for unknown buffer sizes. */
2122 if (WARN_ON_ONCE(size > INT_MAX))
2123 return 0;
2125 str = buf;
2126 end = buf + size;
2128 /* Make sure end is always >= buf */
2129 if (end < buf) {
2130 end = ((void *)-1);
2131 size = end - buf;
2134 while (*fmt) {
2135 const char *old_fmt = fmt;
2136 int read = format_decode(fmt, &spec);
2138 fmt += read;
2140 switch (spec.type) {
2141 case FORMAT_TYPE_NONE: {
2142 int copy = read;
2143 if (str < end) {
2144 if (copy > end - str)
2145 copy = end - str;
2146 memcpy(str, old_fmt, copy);
2148 str += read;
2149 break;
2152 case FORMAT_TYPE_WIDTH:
2153 set_field_width(&spec, va_arg(args, int));
2154 break;
2156 case FORMAT_TYPE_PRECISION:
2157 set_precision(&spec, va_arg(args, int));
2158 break;
2160 case FORMAT_TYPE_CHAR: {
2161 char c;
2163 if (!(spec.flags & LEFT)) {
2164 while (--spec.field_width > 0) {
2165 if (str < end)
2166 *str = ' ';
2167 ++str;
2171 c = (unsigned char) va_arg(args, int);
2172 if (str < end)
2173 *str = c;
2174 ++str;
2175 while (--spec.field_width > 0) {
2176 if (str < end)
2177 *str = ' ';
2178 ++str;
2180 break;
2183 case FORMAT_TYPE_STR:
2184 str = string(str, end, va_arg(args, char *), spec);
2185 break;
2187 case FORMAT_TYPE_PTR:
2188 str = pointer(fmt, str, end, va_arg(args, void *),
2189 spec);
2190 while (isalnum(*fmt))
2191 fmt++;
2192 break;
2194 case FORMAT_TYPE_PERCENT_CHAR:
2195 if (str < end)
2196 *str = '%';
2197 ++str;
2198 break;
2200 case FORMAT_TYPE_INVALID:
2202 * Presumably the arguments passed gcc's type
2203 * checking, but there is no safe or sane way
2204 * for us to continue parsing the format and
2205 * fetching from the va_list; the remaining
2206 * specifiers and arguments would be out of
2207 * sync.
2209 goto out;
2211 default:
2212 switch (spec.type) {
2213 case FORMAT_TYPE_LONG_LONG:
2214 num = va_arg(args, long long);
2215 break;
2216 case FORMAT_TYPE_ULONG:
2217 num = va_arg(args, unsigned long);
2218 break;
2219 case FORMAT_TYPE_LONG:
2220 num = va_arg(args, long);
2221 break;
2222 case FORMAT_TYPE_SIZE_T:
2223 if (spec.flags & SIGN)
2224 num = va_arg(args, ssize_t);
2225 else
2226 num = va_arg(args, size_t);
2227 break;
2228 case FORMAT_TYPE_PTRDIFF:
2229 num = va_arg(args, ptrdiff_t);
2230 break;
2231 case FORMAT_TYPE_UBYTE:
2232 num = (unsigned char) va_arg(args, int);
2233 break;
2234 case FORMAT_TYPE_BYTE:
2235 num = (signed char) va_arg(args, int);
2236 break;
2237 case FORMAT_TYPE_USHORT:
2238 num = (unsigned short) va_arg(args, int);
2239 break;
2240 case FORMAT_TYPE_SHORT:
2241 num = (short) va_arg(args, int);
2242 break;
2243 case FORMAT_TYPE_INT:
2244 num = (int) va_arg(args, int);
2245 break;
2246 default:
2247 num = va_arg(args, unsigned int);
2250 str = number(str, end, num, spec);
2254 out:
2255 if (size > 0) {
2256 if (str < end)
2257 *str = '\0';
2258 else
2259 end[-1] = '\0';
2262 /* the trailing null byte doesn't count towards the total */
2263 return str-buf;
2266 EXPORT_SYMBOL(vsnprintf);
2269 * vscnprintf - Format a string and place it in a buffer
2270 * @buf: The buffer to place the result into
2271 * @size: The size of the buffer, including the trailing null space
2272 * @fmt: The format string to use
2273 * @args: Arguments for the format string
2275 * The return value is the number of characters which have been written into
2276 * the @buf not including the trailing '\0'. If @size is == 0 the function
2277 * returns 0.
2279 * If you're not already dealing with a va_list consider using scnprintf().
2281 * See the vsnprintf() documentation for format string extensions over C99.
2283 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2285 int i;
2287 i = vsnprintf(buf, size, fmt, args);
2289 if (likely(i < size))
2290 return i;
2291 if (size != 0)
2292 return size - 1;
2293 return 0;
2295 EXPORT_SYMBOL(vscnprintf);
2298 * snprintf - Format a string and place it in a buffer
2299 * @buf: The buffer to place the result into
2300 * @size: The size of the buffer, including the trailing null space
2301 * @fmt: The format string to use
2302 * @...: Arguments for the format string
2304 * The return value is the number of characters which would be
2305 * generated for the given input, excluding the trailing null,
2306 * as per ISO C99. If the return is greater than or equal to
2307 * @size, the resulting string is truncated.
2309 * See the vsnprintf() documentation for format string extensions over C99.
2311 int snprintf(char *buf, size_t size, const char *fmt, ...)
2313 va_list args;
2314 int i;
2316 va_start(args, fmt);
2317 i = vsnprintf(buf, size, fmt, args);
2318 va_end(args);
2320 return i;
2322 EXPORT_SYMBOL(snprintf);
2325 * scnprintf - Format a string and place it in a buffer
2326 * @buf: The buffer to place the result into
2327 * @size: The size of the buffer, including the trailing null space
2328 * @fmt: The format string to use
2329 * @...: Arguments for the format string
2331 * The return value is the number of characters written into @buf not including
2332 * the trailing '\0'. If @size is == 0 the function returns 0.
2335 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2337 va_list args;
2338 int i;
2340 va_start(args, fmt);
2341 i = vscnprintf(buf, size, fmt, args);
2342 va_end(args);
2344 return i;
2346 EXPORT_SYMBOL(scnprintf);
2349 * vsprintf - Format a string and place it in a buffer
2350 * @buf: The buffer to place the result into
2351 * @fmt: The format string to use
2352 * @args: Arguments for the format string
2354 * The function returns the number of characters written
2355 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2356 * buffer overflows.
2358 * If you're not already dealing with a va_list consider using sprintf().
2360 * See the vsnprintf() documentation for format string extensions over C99.
2362 int vsprintf(char *buf, const char *fmt, va_list args)
2364 return vsnprintf(buf, INT_MAX, fmt, args);
2366 EXPORT_SYMBOL(vsprintf);
2369 * sprintf - Format a string and place it in a buffer
2370 * @buf: The buffer to place the result into
2371 * @fmt: The format string to use
2372 * @...: Arguments for the format string
2374 * The function returns the number of characters written
2375 * into @buf. Use snprintf() or scnprintf() in order to avoid
2376 * buffer overflows.
2378 * See the vsnprintf() documentation for format string extensions over C99.
2380 int sprintf(char *buf, const char *fmt, ...)
2382 va_list args;
2383 int i;
2385 va_start(args, fmt);
2386 i = vsnprintf(buf, INT_MAX, fmt, args);
2387 va_end(args);
2389 return i;
2391 EXPORT_SYMBOL(sprintf);
2393 #ifdef CONFIG_BINARY_PRINTF
2395 * bprintf service:
2396 * vbin_printf() - VA arguments to binary data
2397 * bstr_printf() - Binary data to text string
2401 * vbin_printf - Parse a format string and place args' binary value in a buffer
2402 * @bin_buf: The buffer to place args' binary value
2403 * @size: The size of the buffer(by words(32bits), not characters)
2404 * @fmt: The format string to use
2405 * @args: Arguments for the format string
2407 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2408 * is skipped.
2410 * The return value is the number of words(32bits) which would be generated for
2411 * the given input.
2413 * NOTE:
2414 * If the return value is greater than @size, the resulting bin_buf is NOT
2415 * valid for bstr_printf().
2417 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2419 struct printf_spec spec = {0};
2420 char *str, *end;
2422 str = (char *)bin_buf;
2423 end = (char *)(bin_buf + size);
2425 #define save_arg(type) \
2426 do { \
2427 if (sizeof(type) == 8) { \
2428 unsigned long long value; \
2429 str = PTR_ALIGN(str, sizeof(u32)); \
2430 value = va_arg(args, unsigned long long); \
2431 if (str + sizeof(type) <= end) { \
2432 *(u32 *)str = *(u32 *)&value; \
2433 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2435 } else { \
2436 unsigned long value; \
2437 str = PTR_ALIGN(str, sizeof(type)); \
2438 value = va_arg(args, int); \
2439 if (str + sizeof(type) <= end) \
2440 *(typeof(type) *)str = (type)value; \
2442 str += sizeof(type); \
2443 } while (0)
2445 while (*fmt) {
2446 int read = format_decode(fmt, &spec);
2448 fmt += read;
2450 switch (spec.type) {
2451 case FORMAT_TYPE_NONE:
2452 case FORMAT_TYPE_PERCENT_CHAR:
2453 break;
2454 case FORMAT_TYPE_INVALID:
2455 goto out;
2457 case FORMAT_TYPE_WIDTH:
2458 case FORMAT_TYPE_PRECISION:
2459 save_arg(int);
2460 break;
2462 case FORMAT_TYPE_CHAR:
2463 save_arg(char);
2464 break;
2466 case FORMAT_TYPE_STR: {
2467 const char *save_str = va_arg(args, char *);
2468 size_t len;
2470 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2471 || (unsigned long)save_str < PAGE_SIZE)
2472 save_str = "(null)";
2473 len = strlen(save_str) + 1;
2474 if (str + len < end)
2475 memcpy(str, save_str, len);
2476 str += len;
2477 break;
2480 case FORMAT_TYPE_PTR:
2481 save_arg(void *);
2482 /* skip all alphanumeric pointer suffixes */
2483 while (isalnum(*fmt))
2484 fmt++;
2485 break;
2487 default:
2488 switch (spec.type) {
2490 case FORMAT_TYPE_LONG_LONG:
2491 save_arg(long long);
2492 break;
2493 case FORMAT_TYPE_ULONG:
2494 case FORMAT_TYPE_LONG:
2495 save_arg(unsigned long);
2496 break;
2497 case FORMAT_TYPE_SIZE_T:
2498 save_arg(size_t);
2499 break;
2500 case FORMAT_TYPE_PTRDIFF:
2501 save_arg(ptrdiff_t);
2502 break;
2503 case FORMAT_TYPE_UBYTE:
2504 case FORMAT_TYPE_BYTE:
2505 save_arg(char);
2506 break;
2507 case FORMAT_TYPE_USHORT:
2508 case FORMAT_TYPE_SHORT:
2509 save_arg(short);
2510 break;
2511 default:
2512 save_arg(int);
2517 out:
2518 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2519 #undef save_arg
2521 EXPORT_SYMBOL_GPL(vbin_printf);
2524 * bstr_printf - Format a string from binary arguments and place it in a buffer
2525 * @buf: The buffer to place the result into
2526 * @size: The size of the buffer, including the trailing null space
2527 * @fmt: The format string to use
2528 * @bin_buf: Binary arguments for the format string
2530 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2531 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2532 * a binary buffer that generated by vbin_printf.
2534 * The format follows C99 vsnprintf, but has some extensions:
2535 * see vsnprintf comment for details.
2537 * The return value is the number of characters which would
2538 * be generated for the given input, excluding the trailing
2539 * '\0', as per ISO C99. If you want to have the exact
2540 * number of characters written into @buf as return value
2541 * (not including the trailing '\0'), use vscnprintf(). If the
2542 * return is greater than or equal to @size, the resulting
2543 * string is truncated.
2545 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2547 struct printf_spec spec = {0};
2548 char *str, *end;
2549 const char *args = (const char *)bin_buf;
2551 if (WARN_ON_ONCE(size > INT_MAX))
2552 return 0;
2554 str = buf;
2555 end = buf + size;
2557 #define get_arg(type) \
2558 ({ \
2559 typeof(type) value; \
2560 if (sizeof(type) == 8) { \
2561 args = PTR_ALIGN(args, sizeof(u32)); \
2562 *(u32 *)&value = *(u32 *)args; \
2563 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2564 } else { \
2565 args = PTR_ALIGN(args, sizeof(type)); \
2566 value = *(typeof(type) *)args; \
2568 args += sizeof(type); \
2569 value; \
2572 /* Make sure end is always >= buf */
2573 if (end < buf) {
2574 end = ((void *)-1);
2575 size = end - buf;
2578 while (*fmt) {
2579 const char *old_fmt = fmt;
2580 int read = format_decode(fmt, &spec);
2582 fmt += read;
2584 switch (spec.type) {
2585 case FORMAT_TYPE_NONE: {
2586 int copy = read;
2587 if (str < end) {
2588 if (copy > end - str)
2589 copy = end - str;
2590 memcpy(str, old_fmt, copy);
2592 str += read;
2593 break;
2596 case FORMAT_TYPE_WIDTH:
2597 set_field_width(&spec, get_arg(int));
2598 break;
2600 case FORMAT_TYPE_PRECISION:
2601 set_precision(&spec, get_arg(int));
2602 break;
2604 case FORMAT_TYPE_CHAR: {
2605 char c;
2607 if (!(spec.flags & LEFT)) {
2608 while (--spec.field_width > 0) {
2609 if (str < end)
2610 *str = ' ';
2611 ++str;
2614 c = (unsigned char) get_arg(char);
2615 if (str < end)
2616 *str = c;
2617 ++str;
2618 while (--spec.field_width > 0) {
2619 if (str < end)
2620 *str = ' ';
2621 ++str;
2623 break;
2626 case FORMAT_TYPE_STR: {
2627 const char *str_arg = args;
2628 args += strlen(str_arg) + 1;
2629 str = string(str, end, (char *)str_arg, spec);
2630 break;
2633 case FORMAT_TYPE_PTR:
2634 str = pointer(fmt, str, end, get_arg(void *), spec);
2635 while (isalnum(*fmt))
2636 fmt++;
2637 break;
2639 case FORMAT_TYPE_PERCENT_CHAR:
2640 if (str < end)
2641 *str = '%';
2642 ++str;
2643 break;
2645 case FORMAT_TYPE_INVALID:
2646 goto out;
2648 default: {
2649 unsigned long long num;
2651 switch (spec.type) {
2653 case FORMAT_TYPE_LONG_LONG:
2654 num = get_arg(long long);
2655 break;
2656 case FORMAT_TYPE_ULONG:
2657 case FORMAT_TYPE_LONG:
2658 num = get_arg(unsigned long);
2659 break;
2660 case FORMAT_TYPE_SIZE_T:
2661 num = get_arg(size_t);
2662 break;
2663 case FORMAT_TYPE_PTRDIFF:
2664 num = get_arg(ptrdiff_t);
2665 break;
2666 case FORMAT_TYPE_UBYTE:
2667 num = get_arg(unsigned char);
2668 break;
2669 case FORMAT_TYPE_BYTE:
2670 num = get_arg(signed char);
2671 break;
2672 case FORMAT_TYPE_USHORT:
2673 num = get_arg(unsigned short);
2674 break;
2675 case FORMAT_TYPE_SHORT:
2676 num = get_arg(short);
2677 break;
2678 case FORMAT_TYPE_UINT:
2679 num = get_arg(unsigned int);
2680 break;
2681 default:
2682 num = get_arg(int);
2685 str = number(str, end, num, spec);
2686 } /* default: */
2687 } /* switch(spec.type) */
2688 } /* while(*fmt) */
2690 out:
2691 if (size > 0) {
2692 if (str < end)
2693 *str = '\0';
2694 else
2695 end[-1] = '\0';
2698 #undef get_arg
2700 /* the trailing null byte doesn't count towards the total */
2701 return str - buf;
2703 EXPORT_SYMBOL_GPL(bstr_printf);
2706 * bprintf - Parse a format string and place args' binary value in a buffer
2707 * @bin_buf: The buffer to place args' binary value
2708 * @size: The size of the buffer(by words(32bits), not characters)
2709 * @fmt: The format string to use
2710 * @...: Arguments for the format string
2712 * The function returns the number of words(u32) written
2713 * into @bin_buf.
2715 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2717 va_list args;
2718 int ret;
2720 va_start(args, fmt);
2721 ret = vbin_printf(bin_buf, size, fmt, args);
2722 va_end(args);
2724 return ret;
2726 EXPORT_SYMBOL_GPL(bprintf);
2728 #endif /* CONFIG_BINARY_PRINTF */
2731 * vsscanf - Unformat a buffer into a list of arguments
2732 * @buf: input buffer
2733 * @fmt: format of buffer
2734 * @args: arguments
2736 int vsscanf(const char *buf, const char *fmt, va_list args)
2738 const char *str = buf;
2739 char *next;
2740 char digit;
2741 int num = 0;
2742 u8 qualifier;
2743 unsigned int base;
2744 union {
2745 long long s;
2746 unsigned long long u;
2747 } val;
2748 s16 field_width;
2749 bool is_sign;
2751 while (*fmt) {
2752 /* skip any white space in format */
2753 /* white space in format matchs any amount of
2754 * white space, including none, in the input.
2756 if (isspace(*fmt)) {
2757 fmt = skip_spaces(++fmt);
2758 str = skip_spaces(str);
2761 /* anything that is not a conversion must match exactly */
2762 if (*fmt != '%' && *fmt) {
2763 if (*fmt++ != *str++)
2764 break;
2765 continue;
2768 if (!*fmt)
2769 break;
2770 ++fmt;
2772 /* skip this conversion.
2773 * advance both strings to next white space
2775 if (*fmt == '*') {
2776 if (!*str)
2777 break;
2778 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2779 /* '%*[' not yet supported, invalid format */
2780 if (*fmt == '[')
2781 return num;
2782 fmt++;
2784 while (!isspace(*str) && *str)
2785 str++;
2786 continue;
2789 /* get field width */
2790 field_width = -1;
2791 if (isdigit(*fmt)) {
2792 field_width = skip_atoi(&fmt);
2793 if (field_width <= 0)
2794 break;
2797 /* get conversion qualifier */
2798 qualifier = -1;
2799 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2800 *fmt == 'z') {
2801 qualifier = *fmt++;
2802 if (unlikely(qualifier == *fmt)) {
2803 if (qualifier == 'h') {
2804 qualifier = 'H';
2805 fmt++;
2806 } else if (qualifier == 'l') {
2807 qualifier = 'L';
2808 fmt++;
2813 if (!*fmt)
2814 break;
2816 if (*fmt == 'n') {
2817 /* return number of characters read so far */
2818 *va_arg(args, int *) = str - buf;
2819 ++fmt;
2820 continue;
2823 if (!*str)
2824 break;
2826 base = 10;
2827 is_sign = false;
2829 switch (*fmt++) {
2830 case 'c':
2832 char *s = (char *)va_arg(args, char*);
2833 if (field_width == -1)
2834 field_width = 1;
2835 do {
2836 *s++ = *str++;
2837 } while (--field_width > 0 && *str);
2838 num++;
2840 continue;
2841 case 's':
2843 char *s = (char *)va_arg(args, char *);
2844 if (field_width == -1)
2845 field_width = SHRT_MAX;
2846 /* first, skip leading white space in buffer */
2847 str = skip_spaces(str);
2849 /* now copy until next white space */
2850 while (*str && !isspace(*str) && field_width--)
2851 *s++ = *str++;
2852 *s = '\0';
2853 num++;
2855 continue;
2857 * Warning: This implementation of the '[' conversion specifier
2858 * deviates from its glibc counterpart in the following ways:
2859 * (1) It does NOT support ranges i.e. '-' is NOT a special
2860 * character
2861 * (2) It cannot match the closing bracket ']' itself
2862 * (3) A field width is required
2863 * (4) '%*[' (discard matching input) is currently not supported
2865 * Example usage:
2866 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2867 * buf1, buf2, buf3);
2868 * if (ret < 3)
2869 * // etc..
2871 case '[':
2873 char *s = (char *)va_arg(args, char *);
2874 DECLARE_BITMAP(set, 256) = {0};
2875 unsigned int len = 0;
2876 bool negate = (*fmt == '^');
2878 /* field width is required */
2879 if (field_width == -1)
2880 return num;
2882 if (negate)
2883 ++fmt;
2885 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2886 set_bit((u8)*fmt, set);
2888 /* no ']' or no character set found */
2889 if (!*fmt || !len)
2890 return num;
2891 ++fmt;
2893 if (negate) {
2894 bitmap_complement(set, set, 256);
2895 /* exclude null '\0' byte */
2896 clear_bit(0, set);
2899 /* match must be non-empty */
2900 if (!test_bit((u8)*str, set))
2901 return num;
2903 while (test_bit((u8)*str, set) && field_width--)
2904 *s++ = *str++;
2905 *s = '\0';
2906 ++num;
2908 continue;
2909 case 'o':
2910 base = 8;
2911 break;
2912 case 'x':
2913 case 'X':
2914 base = 16;
2915 break;
2916 case 'i':
2917 base = 0;
2918 case 'd':
2919 is_sign = true;
2920 case 'u':
2921 break;
2922 case '%':
2923 /* looking for '%' in str */
2924 if (*str++ != '%')
2925 return num;
2926 continue;
2927 default:
2928 /* invalid format; stop here */
2929 return num;
2932 /* have some sort of integer conversion.
2933 * first, skip white space in buffer.
2935 str = skip_spaces(str);
2937 digit = *str;
2938 if (is_sign && digit == '-')
2939 digit = *(str + 1);
2941 if (!digit
2942 || (base == 16 && !isxdigit(digit))
2943 || (base == 10 && !isdigit(digit))
2944 || (base == 8 && (!isdigit(digit) || digit > '7'))
2945 || (base == 0 && !isdigit(digit)))
2946 break;
2948 if (is_sign)
2949 val.s = qualifier != 'L' ?
2950 simple_strtol(str, &next, base) :
2951 simple_strtoll(str, &next, base);
2952 else
2953 val.u = qualifier != 'L' ?
2954 simple_strtoul(str, &next, base) :
2955 simple_strtoull(str, &next, base);
2957 if (field_width > 0 && next - str > field_width) {
2958 if (base == 0)
2959 _parse_integer_fixup_radix(str, &base);
2960 while (next - str > field_width) {
2961 if (is_sign)
2962 val.s = div_s64(val.s, base);
2963 else
2964 val.u = div_u64(val.u, base);
2965 --next;
2969 switch (qualifier) {
2970 case 'H': /* that's 'hh' in format */
2971 if (is_sign)
2972 *va_arg(args, signed char *) = val.s;
2973 else
2974 *va_arg(args, unsigned char *) = val.u;
2975 break;
2976 case 'h':
2977 if (is_sign)
2978 *va_arg(args, short *) = val.s;
2979 else
2980 *va_arg(args, unsigned short *) = val.u;
2981 break;
2982 case 'l':
2983 if (is_sign)
2984 *va_arg(args, long *) = val.s;
2985 else
2986 *va_arg(args, unsigned long *) = val.u;
2987 break;
2988 case 'L':
2989 if (is_sign)
2990 *va_arg(args, long long *) = val.s;
2991 else
2992 *va_arg(args, unsigned long long *) = val.u;
2993 break;
2994 case 'z':
2995 *va_arg(args, size_t *) = val.u;
2996 break;
2997 default:
2998 if (is_sign)
2999 *va_arg(args, int *) = val.s;
3000 else
3001 *va_arg(args, unsigned int *) = val.u;
3002 break;
3004 num++;
3006 if (!next)
3007 break;
3008 str = next;
3011 return num;
3013 EXPORT_SYMBOL(vsscanf);
3016 * sscanf - Unformat a buffer into a list of arguments
3017 * @buf: input buffer
3018 * @fmt: formatting of buffer
3019 * @...: resulting arguments
3021 int sscanf(const char *buf, const char *fmt, ...)
3023 va_list args;
3024 int i;
3026 va_start(args, fmt);
3027 i = vsscanf(buf, fmt, args);
3028 va_end(args);
3030 return i;
3032 EXPORT_SYMBOL(sscanf);