4 * Copyright (C) 1991, 1992 Linus Torvalds
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
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
20 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/math64.h>
27 #include <linux/uaccess.h>
28 #include <linux/ioport.h>
29 #include <linux/dcache.h>
30 #include <linux/cred.h>
31 #include <net/addrconf.h>
33 #include <asm/page.h> /* for PAGE_SIZE */
34 #include <asm/sections.h> /* for dereference_function_descriptor() */
39 * simple_strtoull - convert a string to an unsigned long long
40 * @cp: The start of the string
41 * @endp: A pointer to the end of the parsed string will be placed here
42 * @base: The number base to use
44 * This function is obsolete. Please use kstrtoull instead.
46 unsigned long long simple_strtoull(const char *cp
, char **endp
, unsigned int base
)
48 unsigned long long result
;
51 cp
= _parse_integer_fixup_radix(cp
, &base
);
52 rv
= _parse_integer(cp
, base
, &result
);
54 cp
+= (rv
& ~KSTRTOX_OVERFLOW
);
61 EXPORT_SYMBOL(simple_strtoull
);
64 * simple_strtoul - convert a string to an unsigned long
65 * @cp: The start of the string
66 * @endp: A pointer to the end of the parsed string will be placed here
67 * @base: The number base to use
69 * This function is obsolete. Please use kstrtoul instead.
71 unsigned long simple_strtoul(const char *cp
, char **endp
, unsigned int base
)
73 return simple_strtoull(cp
, endp
, base
);
75 EXPORT_SYMBOL(simple_strtoul
);
78 * simple_strtol - convert a string to a signed long
79 * @cp: The start of the string
80 * @endp: A pointer to the end of the parsed string will be placed here
81 * @base: The number base to use
83 * This function is obsolete. Please use kstrtol instead.
85 long simple_strtol(const char *cp
, char **endp
, unsigned int base
)
88 return -simple_strtoul(cp
+ 1, endp
, base
);
90 return simple_strtoul(cp
, endp
, base
);
92 EXPORT_SYMBOL(simple_strtol
);
95 * simple_strtoll - convert a string to a signed long long
96 * @cp: The start of the string
97 * @endp: A pointer to the end of the parsed string will be placed here
98 * @base: The number base to use
100 * This function is obsolete. Please use kstrtoll instead.
102 long long simple_strtoll(const char *cp
, char **endp
, unsigned int base
)
105 return -simple_strtoull(cp
+ 1, endp
, base
);
107 return simple_strtoull(cp
, endp
, base
);
109 EXPORT_SYMBOL(simple_strtoll
);
111 static noinline_for_stack
112 int skip_atoi(const char **s
)
117 i
= i
*10 + *((*s
)++) - '0';
122 /* Decimal conversion is by far the most typical, and is used
123 * for /proc and /sys data. This directly impacts e.g. top performance
124 * with many processes running. We optimize it for speed
125 * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
126 * (with permission from the author, Douglas W. Jones).
129 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
130 /* Formats correctly any integer in [0, 999999999] */
131 static noinline_for_stack
132 char *put_dec_full9(char *buf
, unsigned q
)
137 * Possible ways to approx. divide by 10
138 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
139 * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul)
140 * (x * 0x6667) >> 18 x < 43699
141 * (x * 0x3334) >> 17 x < 16389
142 * (x * 0x199a) >> 16 x < 16389
143 * (x * 0x0ccd) >> 15 x < 16389
144 * (x * 0x0667) >> 14 x < 2739
145 * (x * 0x0334) >> 13 x < 1029
146 * (x * 0x019a) >> 12 x < 1029
147 * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386)
148 * (x * 0x0067) >> 10 x < 179
149 * (x * 0x0034) >> 9 x < 69 same
150 * (x * 0x001a) >> 8 x < 69 same
151 * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386)
152 * (x * 0x0007) >> 6 x < 19
153 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
155 r
= (q
* (uint64_t)0x1999999a) >> 32;
156 *buf
++ = (q
- 10 * r
) + '0'; /* 1 */
157 q
= (r
* (uint64_t)0x1999999a) >> 32;
158 *buf
++ = (r
- 10 * q
) + '0'; /* 2 */
159 r
= (q
* (uint64_t)0x1999999a) >> 32;
160 *buf
++ = (q
- 10 * r
) + '0'; /* 3 */
161 q
= (r
* (uint64_t)0x1999999a) >> 32;
162 *buf
++ = (r
- 10 * q
) + '0'; /* 4 */
163 r
= (q
* (uint64_t)0x1999999a) >> 32;
164 *buf
++ = (q
- 10 * r
) + '0'; /* 5 */
165 /* Now value is under 10000, can avoid 64-bit multiply */
166 q
= (r
* 0x199a) >> 16;
167 *buf
++ = (r
- 10 * q
) + '0'; /* 6 */
168 r
= (q
* 0xcd) >> 11;
169 *buf
++ = (q
- 10 * r
) + '0'; /* 7 */
170 q
= (r
* 0xcd) >> 11;
171 *buf
++ = (r
- 10 * q
) + '0'; /* 8 */
172 *buf
++ = q
+ '0'; /* 9 */
177 /* Similar to above but do not pad with zeros.
178 * Code can be easily arranged to print 9 digits too, but our callers
179 * always call put_dec_full9() instead when the number has 9 decimal digits.
181 static noinline_for_stack
182 char *put_dec_trunc8(char *buf
, unsigned r
)
186 /* Copy of previous function's body with added early returns */
189 r
= (r
* (uint64_t)0x1999999a) >> 32;
193 q
= (r
* 0x199a) >> 16; /* r <= 9999 */
194 *buf
++ = (r
- 10 * q
) + '0';
197 r
= (q
* 0xcd) >> 11; /* q <= 999 */
198 *buf
++ = (q
- 10 * r
) + '0';
201 q
= (r
* 0xcd) >> 11; /* r <= 99 */
202 *buf
++ = (r
- 10 * q
) + '0';
205 *buf
++ = q
+ '0'; /* q <= 9 */
209 /* There are two algorithms to print larger numbers.
210 * One is generic: divide by 1000000000 and repeatedly print
211 * groups of (up to) 9 digits. It's conceptually simple,
212 * but requires a (unsigned long long) / 1000000000 division.
214 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
215 * manipulates them cleverly and generates groups of 4 decimal digits.
216 * It so happens that it does NOT require long long division.
218 * If long is > 32 bits, division of 64-bit values is relatively easy,
219 * and we will use the first algorithm.
220 * If long long is > 64 bits (strange architecture with VERY large long long),
221 * second algorithm can't be used, and we again use the first one.
223 * Else (if long is 32 bits and long long is 64 bits) we use second one.
226 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
228 /* First algorithm: generic */
231 char *put_dec(char *buf
, unsigned long long n
)
233 if (n
>= 100*1000*1000) {
234 while (n
>= 1000*1000*1000)
235 buf
= put_dec_full9(buf
, do_div(n
, 1000*1000*1000));
236 if (n
>= 100*1000*1000)
237 return put_dec_full9(buf
, n
);
239 return put_dec_trunc8(buf
, n
);
244 /* Second algorithm: valid only for 64-bit long longs */
246 /* See comment in put_dec_full9 for choice of constants */
247 static noinline_for_stack
248 void put_dec_full4(char *buf
, unsigned q
)
251 r
= (q
* 0xccd) >> 15;
252 buf
[0] = (q
- 10 * r
) + '0';
253 q
= (r
* 0xcd) >> 11;
254 buf
[1] = (r
- 10 * q
) + '0';
255 r
= (q
* 0xcd) >> 11;
256 buf
[2] = (q
- 10 * r
) + '0';
261 * Call put_dec_full4 on x % 10000, return x / 10000.
262 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
263 * holds for all x < 1,128,869,999. The largest value this
264 * helper will ever be asked to convert is 1,125,520,955.
265 * (d1 in the put_dec code, assuming n is all-ones).
268 unsigned put_dec_helper4(char *buf
, unsigned x
)
270 uint32_t q
= (x
* (uint64_t)0x346DC5D7) >> 43;
272 put_dec_full4(buf
, x
- q
* 10000);
276 /* Based on code by Douglas W. Jones found at
277 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
278 * (with permission from the author).
279 * Performs no 64-bit division and hence should be fast on 32-bit machines.
282 char *put_dec(char *buf
, unsigned long long n
)
284 uint32_t d3
, d2
, d1
, q
, h
;
286 if (n
< 100*1000*1000)
287 return put_dec_trunc8(buf
, n
);
289 d1
= ((uint32_t)n
>> 16); /* implicit "& 0xffff" */
292 d3
= (h
>> 16); /* implicit "& 0xffff" */
294 q
= 656 * d3
+ 7296 * d2
+ 5536 * d1
+ ((uint32_t)n
& 0xffff);
295 q
= put_dec_helper4(buf
, q
);
297 q
+= 7671 * d3
+ 9496 * d2
+ 6 * d1
;
298 q
= put_dec_helper4(buf
+4, q
);
300 q
+= 4749 * d3
+ 42 * d2
;
301 q
= put_dec_helper4(buf
+8, q
);
306 buf
= put_dec_trunc8(buf
, q
);
307 else while (buf
[-1] == '0')
316 * Convert passed number to decimal string.
317 * Returns the length of string. On buffer overflow, returns 0.
319 * If speed is not important, use snprintf(). It's easy to read the code.
321 int num_to_str(char *buf
, int size
, unsigned long long num
)
323 char tmp
[sizeof(num
) * 3];
326 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
331 len
= put_dec(tmp
, num
) - tmp
;
336 for (idx
= 0; idx
< len
; ++idx
)
337 buf
[idx
] = tmp
[len
- idx
- 1];
341 #define ZEROPAD 1 /* pad with zero */
342 #define SIGN 2 /* unsigned/signed long */
343 #define PLUS 4 /* show plus */
344 #define SPACE 8 /* space if plus */
345 #define LEFT 16 /* left justified */
346 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
347 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
350 FORMAT_TYPE_NONE
, /* Just a string part */
352 FORMAT_TYPE_PRECISION
,
356 FORMAT_TYPE_PERCENT_CHAR
,
358 FORMAT_TYPE_LONG_LONG
,
373 u8 type
; /* format_type enum */
374 u8 flags
; /* flags to number() */
375 u8 base
; /* number base, 8, 10 or 16 only */
376 u8 qualifier
; /* number qualifier, one of 'hHlLtzZ' */
377 s16 field_width
; /* width of output field */
378 s16 precision
; /* # of digits/chars */
381 static noinline_for_stack
382 char *number(char *buf
, char *end
, unsigned long long num
,
383 struct printf_spec spec
)
385 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
386 static const char digits
[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
391 int need_pfx
= ((spec
.flags
& SPECIAL
) && spec
.base
!= 10);
393 bool is_zero
= num
== 0LL;
395 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
396 * produces same digits or (maybe lowercased) letters */
397 locase
= (spec
.flags
& SMALL
);
398 if (spec
.flags
& LEFT
)
399 spec
.flags
&= ~ZEROPAD
;
401 if (spec
.flags
& SIGN
) {
402 if ((signed long long)num
< 0) {
404 num
= -(signed long long)num
;
406 } else if (spec
.flags
& PLUS
) {
409 } else if (spec
.flags
& SPACE
) {
416 spec
.field_width
-= 2;
421 /* generate full string in tmp[], in reverse order */
424 tmp
[i
++] = digits
[num
] | locase
;
425 /* Generic code, for any base:
427 tmp[i++] = (digits[do_div(num,base)] | locase);
430 else if (spec
.base
!= 10) { /* 8 or 16 */
431 int mask
= spec
.base
- 1;
437 tmp
[i
++] = (digits
[((unsigned char)num
) & mask
] | locase
);
440 } else { /* base 10 */
441 i
= put_dec(tmp
, num
) - tmp
;
444 /* printing 100 using %2d gives "100", not "00" */
445 if (i
> spec
.precision
)
447 /* leading space padding */
448 spec
.field_width
-= spec
.precision
;
449 if (!(spec
.flags
& (ZEROPAD
+LEFT
))) {
450 while (--spec
.field_width
>= 0) {
462 /* "0x" / "0" prefix */
464 if (spec
.base
== 16 || !is_zero
) {
469 if (spec
.base
== 16) {
471 *buf
= ('X' | locase
);
475 /* zero or space padding */
476 if (!(spec
.flags
& LEFT
)) {
477 char c
= (spec
.flags
& ZEROPAD
) ? '0' : ' ';
478 while (--spec
.field_width
>= 0) {
484 /* hmm even more zero padding? */
485 while (i
<= --spec
.precision
) {
490 /* actual digits of result */
496 /* trailing space padding */
497 while (--spec
.field_width
>= 0) {
506 static noinline_for_stack
507 char *string(char *buf
, char *end
, const char *s
, struct printf_spec spec
)
511 if ((unsigned long)s
< PAGE_SIZE
)
514 len
= strnlen(s
, spec
.precision
);
516 if (!(spec
.flags
& LEFT
)) {
517 while (len
< spec
.field_width
--) {
523 for (i
= 0; i
< len
; ++i
) {
528 while (len
< spec
.field_width
--) {
537 static void widen(char *buf
, char *end
, unsigned len
, unsigned spaces
)
540 if (buf
>= end
) /* nowhere to put anything */
543 if (size
<= spaces
) {
544 memset(buf
, ' ', size
);
548 if (len
> size
- spaces
)
550 memmove(buf
+ spaces
, buf
, len
);
552 memset(buf
, ' ', spaces
);
555 static noinline_for_stack
556 char *dentry_name(char *buf
, char *end
, const struct dentry
*d
, struct printf_spec spec
,
559 const char *array
[4], *s
;
560 const struct dentry
*p
;
565 case '2': case '3': case '4':
566 depth
= fmt
[1] - '0';
573 for (i
= 0; i
< depth
; i
++, d
= p
) {
574 p
= ACCESS_ONCE(d
->d_parent
);
575 array
[i
] = ACCESS_ONCE(d
->d_name
.name
);
584 for (n
= 0; n
!= spec
.precision
; n
++, buf
++) {
596 if (n
< spec
.field_width
) {
597 /* we want to pad the sucker */
598 unsigned spaces
= spec
.field_width
- n
;
599 if (!(spec
.flags
& LEFT
)) {
600 widen(buf
- n
, end
, n
, spaces
);
612 static noinline_for_stack
613 char *symbol_string(char *buf
, char *end
, void *ptr
,
614 struct printf_spec spec
, const char *fmt
)
617 #ifdef CONFIG_KALLSYMS
618 char sym
[KSYM_SYMBOL_LEN
];
622 ptr
= __builtin_extract_return_addr(ptr
);
623 value
= (unsigned long)ptr
;
625 #ifdef CONFIG_KALLSYMS
627 sprint_backtrace(sym
, value
);
628 else if (*fmt
!= 'f' && *fmt
!= 's')
629 sprint_symbol(sym
, value
);
631 sprint_symbol_no_offset(sym
, value
);
633 return string(buf
, end
, sym
, spec
);
635 spec
.field_width
= 2 * sizeof(void *);
636 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
639 return number(buf
, end
, value
, spec
);
643 static noinline_for_stack
644 char *resource_string(char *buf
, char *end
, struct resource
*res
,
645 struct printf_spec spec
, const char *fmt
)
647 #ifndef IO_RSRC_PRINTK_SIZE
648 #define IO_RSRC_PRINTK_SIZE 6
651 #ifndef MEM_RSRC_PRINTK_SIZE
652 #define MEM_RSRC_PRINTK_SIZE 10
654 static const struct printf_spec io_spec
= {
656 .field_width
= IO_RSRC_PRINTK_SIZE
,
658 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
660 static const struct printf_spec mem_spec
= {
662 .field_width
= MEM_RSRC_PRINTK_SIZE
,
664 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
666 static const struct printf_spec bus_spec
= {
670 .flags
= SMALL
| ZEROPAD
,
672 static const struct printf_spec dec_spec
= {
677 static const struct printf_spec str_spec
= {
682 static const struct printf_spec flag_spec
= {
685 .flags
= SPECIAL
| SMALL
,
688 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
689 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
690 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
691 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
692 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
693 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
694 char sym
[max(2*RSRC_BUF_SIZE
+ DECODED_BUF_SIZE
,
695 2*RSRC_BUF_SIZE
+ FLAG_BUF_SIZE
+ RAW_BUF_SIZE
)];
697 char *p
= sym
, *pend
= sym
+ sizeof(sym
);
698 int decode
= (fmt
[0] == 'R') ? 1 : 0;
699 const struct printf_spec
*specp
;
702 if (res
->flags
& IORESOURCE_IO
) {
703 p
= string(p
, pend
, "io ", str_spec
);
705 } else if (res
->flags
& IORESOURCE_MEM
) {
706 p
= string(p
, pend
, "mem ", str_spec
);
708 } else if (res
->flags
& IORESOURCE_IRQ
) {
709 p
= string(p
, pend
, "irq ", str_spec
);
711 } else if (res
->flags
& IORESOURCE_DMA
) {
712 p
= string(p
, pend
, "dma ", str_spec
);
714 } else if (res
->flags
& IORESOURCE_BUS
) {
715 p
= string(p
, pend
, "bus ", str_spec
);
718 p
= string(p
, pend
, "??? ", str_spec
);
722 if (decode
&& res
->flags
& IORESOURCE_UNSET
) {
723 p
= string(p
, pend
, "size ", str_spec
);
724 p
= number(p
, pend
, resource_size(res
), *specp
);
726 p
= number(p
, pend
, res
->start
, *specp
);
727 if (res
->start
!= res
->end
) {
729 p
= number(p
, pend
, res
->end
, *specp
);
733 if (res
->flags
& IORESOURCE_MEM_64
)
734 p
= string(p
, pend
, " 64bit", str_spec
);
735 if (res
->flags
& IORESOURCE_PREFETCH
)
736 p
= string(p
, pend
, " pref", str_spec
);
737 if (res
->flags
& IORESOURCE_WINDOW
)
738 p
= string(p
, pend
, " window", str_spec
);
739 if (res
->flags
& IORESOURCE_DISABLED
)
740 p
= string(p
, pend
, " disabled", str_spec
);
742 p
= string(p
, pend
, " flags ", str_spec
);
743 p
= number(p
, pend
, res
->flags
, flag_spec
);
748 return string(buf
, end
, sym
, spec
);
751 static noinline_for_stack
752 char *hex_string(char *buf
, char *end
, u8
*addr
, struct printf_spec spec
,
755 int i
, len
= 1; /* if we pass '%ph[CDN]', field width remains
756 negative value, fallback to the default */
759 if (spec
.field_width
== 0)
760 /* nothing to print */
763 if (ZERO_OR_NULL_PTR(addr
))
765 return string(buf
, end
, NULL
, spec
);
782 if (spec
.field_width
> 0)
783 len
= min_t(int, spec
.field_width
, 64);
785 for (i
= 0; i
< len
&& buf
< end
- 1; i
++) {
786 buf
= hex_byte_pack(buf
, addr
[i
]);
788 if (buf
< end
&& separator
&& i
!= len
- 1)
795 static noinline_for_stack
796 char *mac_address_string(char *buf
, char *end
, u8
*addr
,
797 struct printf_spec spec
, const char *fmt
)
799 char mac_addr
[sizeof("xx:xx:xx:xx:xx:xx")];
803 bool reversed
= false;
819 for (i
= 0; i
< 6; i
++) {
821 p
= hex_byte_pack(p
, addr
[5 - i
]);
823 p
= hex_byte_pack(p
, addr
[i
]);
825 if (fmt
[0] == 'M' && i
!= 5)
830 return string(buf
, end
, mac_addr
, spec
);
833 static noinline_for_stack
834 char *ip4_string(char *p
, const u8
*addr
, const char *fmt
)
837 bool leading_zeros
= (fmt
[0] == 'i');
862 for (i
= 0; i
< 4; i
++) {
863 char temp
[3]; /* hold each IP quad in reverse order */
864 int digits
= put_dec_trunc8(temp
, addr
[index
]) - temp
;
871 /* reverse the digits in the quad */
883 static noinline_for_stack
884 char *ip6_compressed_string(char *p
, const char *addr
)
887 unsigned char zerolength
[8];
892 bool needcolon
= false;
896 memcpy(&in6
, addr
, sizeof(struct in6_addr
));
898 useIPv4
= ipv6_addr_v4mapped(&in6
) || ipv6_addr_is_isatap(&in6
);
900 memset(zerolength
, 0, sizeof(zerolength
));
907 /* find position of longest 0 run */
908 for (i
= 0; i
< range
; i
++) {
909 for (j
= i
; j
< range
; j
++) {
910 if (in6
.s6_addr16
[j
] != 0)
915 for (i
= 0; i
< range
; i
++) {
916 if (zerolength
[i
] > longest
) {
917 longest
= zerolength
[i
];
921 if (longest
== 1) /* don't compress a single 0 */
925 for (i
= 0; i
< range
; i
++) {
927 if (needcolon
|| i
== 0)
938 /* hex u16 without leading 0s */
939 word
= ntohs(in6
.s6_addr16
[i
]);
944 p
= hex_byte_pack(p
, hi
);
946 *p
++ = hex_asc_lo(hi
);
947 p
= hex_byte_pack(p
, lo
);
950 p
= hex_byte_pack(p
, lo
);
952 *p
++ = hex_asc_lo(lo
);
959 p
= ip4_string(p
, &in6
.s6_addr
[12], "I4");
966 static noinline_for_stack
967 char *ip6_string(char *p
, const char *addr
, const char *fmt
)
971 for (i
= 0; i
< 8; i
++) {
972 p
= hex_byte_pack(p
, *addr
++);
973 p
= hex_byte_pack(p
, *addr
++);
974 if (fmt
[0] == 'I' && i
!= 7)
982 static noinline_for_stack
983 char *ip6_addr_string(char *buf
, char *end
, const u8
*addr
,
984 struct printf_spec spec
, const char *fmt
)
986 char ip6_addr
[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
988 if (fmt
[0] == 'I' && fmt
[2] == 'c')
989 ip6_compressed_string(ip6_addr
, addr
);
991 ip6_string(ip6_addr
, addr
, fmt
);
993 return string(buf
, end
, ip6_addr
, spec
);
996 static noinline_for_stack
997 char *ip4_addr_string(char *buf
, char *end
, const u8
*addr
,
998 struct printf_spec spec
, const char *fmt
)
1000 char ip4_addr
[sizeof("255.255.255.255")];
1002 ip4_string(ip4_addr
, addr
, fmt
);
1004 return string(buf
, end
, ip4_addr
, spec
);
1007 static noinline_for_stack
1008 char *ip6_addr_string_sa(char *buf
, char *end
, const struct sockaddr_in6
*sa
,
1009 struct printf_spec spec
, const char *fmt
)
1011 bool have_p
= false, have_s
= false, have_f
= false, have_c
= false;
1012 char ip6_addr
[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1013 sizeof(":12345") + sizeof("/123456789") +
1014 sizeof("%1234567890")];
1015 char *p
= ip6_addr
, *pend
= ip6_addr
+ sizeof(ip6_addr
);
1016 const u8
*addr
= (const u8
*) &sa
->sin6_addr
;
1017 char fmt6
[2] = { fmt
[0], '6' };
1021 while (isalpha(*++fmt
)) {
1038 if (have_p
|| have_s
|| have_f
) {
1043 if (fmt6
[0] == 'I' && have_c
)
1044 p
= ip6_compressed_string(ip6_addr
+ off
, addr
);
1046 p
= ip6_string(ip6_addr
+ off
, addr
, fmt6
);
1048 if (have_p
|| have_s
|| have_f
)
1053 p
= number(p
, pend
, ntohs(sa
->sin6_port
), spec
);
1057 p
= number(p
, pend
, ntohl(sa
->sin6_flowinfo
&
1058 IPV6_FLOWINFO_MASK
), spec
);
1062 p
= number(p
, pend
, sa
->sin6_scope_id
, spec
);
1066 return string(buf
, end
, ip6_addr
, spec
);
1069 static noinline_for_stack
1070 char *ip4_addr_string_sa(char *buf
, char *end
, const struct sockaddr_in
*sa
,
1071 struct printf_spec spec
, const char *fmt
)
1073 bool have_p
= false;
1074 char *p
, ip4_addr
[sizeof("255.255.255.255") + sizeof(":12345")];
1075 char *pend
= ip4_addr
+ sizeof(ip4_addr
);
1076 const u8
*addr
= (const u8
*) &sa
->sin_addr
.s_addr
;
1077 char fmt4
[3] = { fmt
[0], '4', 0 };
1080 while (isalpha(*++fmt
)) {
1094 p
= ip4_string(ip4_addr
, addr
, fmt4
);
1097 p
= number(p
, pend
, ntohs(sa
->sin_port
), spec
);
1101 return string(buf
, end
, ip4_addr
, spec
);
1104 static noinline_for_stack
1105 char *uuid_string(char *buf
, char *end
, const u8
*addr
,
1106 struct printf_spec spec
, const char *fmt
)
1108 char uuid
[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1111 static const u8 be
[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1112 static const u8 le
[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1113 const u8
*index
= be
;
1118 uc
= true; /* fall-through */
1127 for (i
= 0; i
< 16; i
++) {
1128 p
= hex_byte_pack(p
, addr
[index
[i
]]);
1148 return string(buf
, end
, uuid
, spec
);
1152 char *netdev_feature_string(char *buf
, char *end
, const u8
*addr
,
1153 struct printf_spec spec
)
1155 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
1156 if (spec
.field_width
== -1)
1157 spec
.field_width
= 2 + 2 * sizeof(netdev_features_t
);
1160 return number(buf
, end
, *(const netdev_features_t
*)addr
, spec
);
1163 static noinline_for_stack
1164 char *address_val(char *buf
, char *end
, const void *addr
,
1165 struct printf_spec spec
, const char *fmt
)
1167 unsigned long long num
;
1169 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
1174 num
= *(const dma_addr_t
*)addr
;
1175 spec
.field_width
= sizeof(dma_addr_t
) * 2 + 2;
1179 num
= *(const phys_addr_t
*)addr
;
1180 spec
.field_width
= sizeof(phys_addr_t
) * 2 + 2;
1184 return number(buf
, end
, num
, spec
);
1187 int kptr_restrict __read_mostly
;
1190 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1191 * by an extra set of alphanumeric characters that are extended format
1194 * Right now we handle:
1196 * - 'F' For symbolic function descriptor pointers with offset
1197 * - 'f' For simple symbolic function names without offset
1198 * - 'S' For symbolic direct pointers with offset
1199 * - 's' For symbolic direct pointers without offset
1200 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1201 * - 'B' For backtraced symbolic direct pointers with offset
1202 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1203 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1204 * - 'M' For a 6-byte MAC address, it prints the address in the
1205 * usual colon-separated hex notation
1206 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1207 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1208 * with a dash-separated hex notation
1209 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1210 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1211 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1212 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1214 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1215 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1216 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1217 * IPv6 omits the colons (01020304...0f)
1218 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1220 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1221 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1222 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1223 * - 'I[6S]c' for IPv6 addresses printed as specified by
1224 * http://tools.ietf.org/html/rfc5952
1225 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1226 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1227 * Options for %pU are:
1228 * b big endian lower case hex (default)
1229 * B big endian UPPER case hex
1230 * l little endian lower case hex
1231 * L little endian UPPER case hex
1232 * big endian output byte order is:
1233 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1234 * little endian output byte order is:
1235 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1236 * - 'V' For a struct va_format which contains a format string * and va_list *,
1237 * call vsnprintf(->format, *->va_list).
1238 * Implements a "recursive vsnprintf".
1239 * Do not use this feature without some mechanism to verify the
1240 * correctness of the format string and va_list arguments.
1241 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1242 * - 'NF' For a netdev_features_t
1243 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1244 * a certain separator (' ' by default):
1248 * The maximum supported length is 64 bytes of the input. Consider
1249 * to use print_hex_dump() for the larger input.
1250 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1251 * (default assumed to be phys_addr_t, passed by reference)
1252 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1253 * - 'D[234]' Same as 'd' but for a struct file
1255 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1256 * function pointers are really function descriptors, which contain a
1257 * pointer to the real address.
1259 static noinline_for_stack
1260 char *pointer(const char *fmt
, char *buf
, char *end
, void *ptr
,
1261 struct printf_spec spec
)
1263 int default_width
= 2 * sizeof(void *) + (spec
.flags
& SPECIAL
? 2 : 0);
1265 if (!ptr
&& *fmt
!= 'K') {
1267 * Print (null) with the same width as a pointer so it makes
1268 * tabular output look nice.
1270 if (spec
.field_width
== -1)
1271 spec
.field_width
= default_width
;
1272 return string(buf
, end
, "(null)", spec
);
1278 ptr
= dereference_function_descriptor(ptr
);
1283 return symbol_string(buf
, end
, ptr
, spec
, fmt
);
1286 return resource_string(buf
, end
, ptr
, spec
, fmt
);
1288 return hex_string(buf
, end
, ptr
, spec
, fmt
);
1289 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1290 case 'm': /* Contiguous: 000102030405 */
1292 /* [mM]R (Reverse order; Bluetooth) */
1293 return mac_address_string(buf
, end
, ptr
, spec
, fmt
);
1294 case 'I': /* Formatted IP supported
1296 * 6: 0001:0203:...:0708
1297 * 6c: 1::708 or 1::1.2.3.4
1299 case 'i': /* Contiguous:
1300 * 4: 001.002.003.004
1305 return ip6_addr_string(buf
, end
, ptr
, spec
, fmt
);
1307 return ip4_addr_string(buf
, end
, ptr
, spec
, fmt
);
1310 struct sockaddr raw
;
1311 struct sockaddr_in v4
;
1312 struct sockaddr_in6 v6
;
1315 switch (sa
->raw
.sa_family
) {
1317 return ip4_addr_string_sa(buf
, end
, &sa
->v4
, spec
, fmt
);
1319 return ip6_addr_string_sa(buf
, end
, &sa
->v6
, spec
, fmt
);
1321 return string(buf
, end
, "(invalid address)", spec
);
1326 return uuid_string(buf
, end
, ptr
, spec
, fmt
);
1331 va_copy(va
, *((struct va_format
*)ptr
)->va
);
1332 buf
+= vsnprintf(buf
, end
> buf
? end
- buf
: 0,
1333 ((struct va_format
*)ptr
)->fmt
, va
);
1339 * %pK cannot be used in IRQ context because its test
1340 * for CAP_SYSLOG would be meaningless.
1342 if (kptr_restrict
&& (in_irq() || in_serving_softirq() ||
1344 if (spec
.field_width
== -1)
1345 spec
.field_width
= default_width
;
1346 return string(buf
, end
, "pK-error", spec
);
1349 switch (kptr_restrict
) {
1351 /* Always print %pK values */
1355 * Only print the real pointer value if the current
1356 * process has CAP_SYSLOG and is running with the
1357 * same credentials it started with. This is because
1358 * access to files is checked at open() time, but %pK
1359 * checks permission at read() time. We don't want to
1360 * leak pointer values if a binary opens a file using
1361 * %pK and then elevates privileges before reading it.
1363 const struct cred
*cred
= current_cred();
1365 if (!has_capability_noaudit(current
, CAP_SYSLOG
) ||
1366 !uid_eq(cred
->euid
, cred
->uid
) ||
1367 !gid_eq(cred
->egid
, cred
->gid
))
1373 /* Always print 0's for %pK */
1382 return netdev_feature_string(buf
, end
, ptr
, spec
);
1386 return address_val(buf
, end
, ptr
, spec
, fmt
);
1388 return dentry_name(buf
, end
, ptr
, spec
, fmt
);
1390 return dentry_name(buf
, end
,
1391 ((const struct file
*)ptr
)->f_path
.dentry
,
1394 spec
.flags
|= SMALL
;
1395 if (spec
.field_width
== -1) {
1396 spec
.field_width
= default_width
;
1397 spec
.flags
|= ZEROPAD
;
1401 return number(buf
, end
, (unsigned long) ptr
, spec
);
1405 * Helper function to decode printf style format.
1406 * Each call decode a token from the format and return the
1407 * number of characters read (or likely the delta where it wants
1408 * to go on the next call).
1409 * The decoded token is returned through the parameters
1411 * 'h', 'l', or 'L' for integer fields
1412 * 'z' support added 23/7/1999 S.H.
1413 * 'z' changed to 'Z' --davidm 1/25/99
1414 * 't' added for ptrdiff_t
1416 * @fmt: the format string
1417 * @type of the token returned
1418 * @flags: various flags such as +, -, # tokens..
1419 * @field_width: overwritten width
1420 * @base: base of the number (octal, hex, ...)
1421 * @precision: precision of a number
1422 * @qualifier: qualifier of a number (long, size_t, ...)
1424 static noinline_for_stack
1425 int format_decode(const char *fmt
, struct printf_spec
*spec
)
1427 const char *start
= fmt
;
1429 /* we finished early by reading the field width */
1430 if (spec
->type
== FORMAT_TYPE_WIDTH
) {
1431 if (spec
->field_width
< 0) {
1432 spec
->field_width
= -spec
->field_width
;
1433 spec
->flags
|= LEFT
;
1435 spec
->type
= FORMAT_TYPE_NONE
;
1439 /* we finished early by reading the precision */
1440 if (spec
->type
== FORMAT_TYPE_PRECISION
) {
1441 if (spec
->precision
< 0)
1442 spec
->precision
= 0;
1444 spec
->type
= FORMAT_TYPE_NONE
;
1449 spec
->type
= FORMAT_TYPE_NONE
;
1451 for (; *fmt
; ++fmt
) {
1456 /* Return the current non-format string */
1457 if (fmt
!= start
|| !*fmt
)
1463 while (1) { /* this also skips first '%' */
1469 case '-': spec
->flags
|= LEFT
; break;
1470 case '+': spec
->flags
|= PLUS
; break;
1471 case ' ': spec
->flags
|= SPACE
; break;
1472 case '#': spec
->flags
|= SPECIAL
; break;
1473 case '0': spec
->flags
|= ZEROPAD
; break;
1474 default: found
= false;
1481 /* get field width */
1482 spec
->field_width
= -1;
1485 spec
->field_width
= skip_atoi(&fmt
);
1486 else if (*fmt
== '*') {
1487 /* it's the next argument */
1488 spec
->type
= FORMAT_TYPE_WIDTH
;
1489 return ++fmt
- start
;
1493 /* get the precision */
1494 spec
->precision
= -1;
1497 if (isdigit(*fmt
)) {
1498 spec
->precision
= skip_atoi(&fmt
);
1499 if (spec
->precision
< 0)
1500 spec
->precision
= 0;
1501 } else if (*fmt
== '*') {
1502 /* it's the next argument */
1503 spec
->type
= FORMAT_TYPE_PRECISION
;
1504 return ++fmt
- start
;
1509 /* get the conversion qualifier */
1510 spec
->qualifier
= -1;
1511 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
1512 _tolower(*fmt
) == 'z' || *fmt
== 't') {
1513 spec
->qualifier
= *fmt
++;
1514 if (unlikely(spec
->qualifier
== *fmt
)) {
1515 if (spec
->qualifier
== 'l') {
1516 spec
->qualifier
= 'L';
1518 } else if (spec
->qualifier
== 'h') {
1519 spec
->qualifier
= 'H';
1529 spec
->type
= FORMAT_TYPE_CHAR
;
1530 return ++fmt
- start
;
1533 spec
->type
= FORMAT_TYPE_STR
;
1534 return ++fmt
- start
;
1537 spec
->type
= FORMAT_TYPE_PTR
;
1542 spec
->type
= FORMAT_TYPE_NRCHARS
;
1543 return ++fmt
- start
;
1546 spec
->type
= FORMAT_TYPE_PERCENT_CHAR
;
1547 return ++fmt
- start
;
1549 /* integer number formats - set up the flags and "break" */
1555 spec
->flags
|= SMALL
;
1563 spec
->flags
|= SIGN
;
1568 spec
->type
= FORMAT_TYPE_INVALID
;
1572 if (spec
->qualifier
== 'L')
1573 spec
->type
= FORMAT_TYPE_LONG_LONG
;
1574 else if (spec
->qualifier
== 'l') {
1575 if (spec
->flags
& SIGN
)
1576 spec
->type
= FORMAT_TYPE_LONG
;
1578 spec
->type
= FORMAT_TYPE_ULONG
;
1579 } else if (_tolower(spec
->qualifier
) == 'z') {
1580 spec
->type
= FORMAT_TYPE_SIZE_T
;
1581 } else if (spec
->qualifier
== 't') {
1582 spec
->type
= FORMAT_TYPE_PTRDIFF
;
1583 } else if (spec
->qualifier
== 'H') {
1584 if (spec
->flags
& SIGN
)
1585 spec
->type
= FORMAT_TYPE_BYTE
;
1587 spec
->type
= FORMAT_TYPE_UBYTE
;
1588 } else if (spec
->qualifier
== 'h') {
1589 if (spec
->flags
& SIGN
)
1590 spec
->type
= FORMAT_TYPE_SHORT
;
1592 spec
->type
= FORMAT_TYPE_USHORT
;
1594 if (spec
->flags
& SIGN
)
1595 spec
->type
= FORMAT_TYPE_INT
;
1597 spec
->type
= FORMAT_TYPE_UINT
;
1600 return ++fmt
- start
;
1604 * vsnprintf - Format a string and place it in a buffer
1605 * @buf: The buffer to place the result into
1606 * @size: The size of the buffer, including the trailing null space
1607 * @fmt: The format string to use
1608 * @args: Arguments for the format string
1610 * This function follows C99 vsnprintf, but has some extensions:
1611 * %pS output the name of a text symbol with offset
1612 * %ps output the name of a text symbol without offset
1613 * %pF output the name of a function pointer with its offset
1614 * %pf output the name of a function pointer without its offset
1615 * %pB output the name of a backtrace symbol with its offset
1616 * %pR output the address range in a struct resource with decoded flags
1617 * %pr output the address range in a struct resource with raw flags
1618 * %pM output a 6-byte MAC address with colons
1619 * %pMR output a 6-byte MAC address with colons in reversed order
1620 * %pMF output a 6-byte MAC address with dashes
1621 * %pm output a 6-byte MAC address without colons
1622 * %pmR output a 6-byte MAC address without colons in reversed order
1623 * %pI4 print an IPv4 address without leading zeros
1624 * %pi4 print an IPv4 address with leading zeros
1625 * %pI6 print an IPv6 address with colons
1626 * %pi6 print an IPv6 address without colons
1627 * %pI6c print an IPv6 address as specified by RFC 5952
1628 * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1629 * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1630 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1632 * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1633 * bytes of the input)
1636 * ** Please update Documentation/printk-formats.txt when making changes **
1638 * The return value is the number of characters which would
1639 * be generated for the given input, excluding the trailing
1640 * '\0', as per ISO C99. If you want to have the exact
1641 * number of characters written into @buf as return value
1642 * (not including the trailing '\0'), use vscnprintf(). If the
1643 * return is greater than or equal to @size, the resulting
1644 * string is truncated.
1646 * If you're not already dealing with a va_list consider using snprintf().
1648 int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1650 unsigned long long num
;
1652 struct printf_spec spec
= {0};
1654 /* Reject out-of-range values early. Large positive sizes are
1655 used for unknown buffer sizes. */
1656 if (WARN_ON_ONCE((int) size
< 0))
1662 /* Make sure end is always >= buf */
1669 const char *old_fmt
= fmt
;
1670 int read
= format_decode(fmt
, &spec
);
1674 switch (spec
.type
) {
1675 case FORMAT_TYPE_NONE
: {
1678 if (copy
> end
- str
)
1680 memcpy(str
, old_fmt
, copy
);
1686 case FORMAT_TYPE_WIDTH
:
1687 spec
.field_width
= va_arg(args
, int);
1690 case FORMAT_TYPE_PRECISION
:
1691 spec
.precision
= va_arg(args
, int);
1694 case FORMAT_TYPE_CHAR
: {
1697 if (!(spec
.flags
& LEFT
)) {
1698 while (--spec
.field_width
> 0) {
1705 c
= (unsigned char) va_arg(args
, int);
1709 while (--spec
.field_width
> 0) {
1717 case FORMAT_TYPE_STR
:
1718 str
= string(str
, end
, va_arg(args
, char *), spec
);
1721 case FORMAT_TYPE_PTR
:
1722 str
= pointer(fmt
+1, str
, end
, va_arg(args
, void *),
1724 while (isalnum(*fmt
))
1728 case FORMAT_TYPE_PERCENT_CHAR
:
1734 case FORMAT_TYPE_INVALID
:
1740 case FORMAT_TYPE_NRCHARS
: {
1742 * Since %n poses a greater security risk than
1743 * utility, ignore %n and skip its argument.
1747 WARN_ONCE(1, "Please remove ignored %%n in '%s'\n",
1750 skip_arg
= va_arg(args
, void *);
1755 switch (spec
.type
) {
1756 case FORMAT_TYPE_LONG_LONG
:
1757 num
= va_arg(args
, long long);
1759 case FORMAT_TYPE_ULONG
:
1760 num
= va_arg(args
, unsigned long);
1762 case FORMAT_TYPE_LONG
:
1763 num
= va_arg(args
, long);
1765 case FORMAT_TYPE_SIZE_T
:
1766 if (spec
.flags
& SIGN
)
1767 num
= va_arg(args
, ssize_t
);
1769 num
= va_arg(args
, size_t);
1771 case FORMAT_TYPE_PTRDIFF
:
1772 num
= va_arg(args
, ptrdiff_t);
1774 case FORMAT_TYPE_UBYTE
:
1775 num
= (unsigned char) va_arg(args
, int);
1777 case FORMAT_TYPE_BYTE
:
1778 num
= (signed char) va_arg(args
, int);
1780 case FORMAT_TYPE_USHORT
:
1781 num
= (unsigned short) va_arg(args
, int);
1783 case FORMAT_TYPE_SHORT
:
1784 num
= (short) va_arg(args
, int);
1786 case FORMAT_TYPE_INT
:
1787 num
= (int) va_arg(args
, int);
1790 num
= va_arg(args
, unsigned int);
1793 str
= number(str
, end
, num
, spec
);
1804 /* the trailing null byte doesn't count towards the total */
1808 EXPORT_SYMBOL(vsnprintf
);
1811 * vscnprintf - Format a string and place it in a buffer
1812 * @buf: The buffer to place the result into
1813 * @size: The size of the buffer, including the trailing null space
1814 * @fmt: The format string to use
1815 * @args: Arguments for the format string
1817 * The return value is the number of characters which have been written into
1818 * the @buf not including the trailing '\0'. If @size is == 0 the function
1821 * If you're not already dealing with a va_list consider using scnprintf().
1823 * See the vsnprintf() documentation for format string extensions over C99.
1825 int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1829 i
= vsnprintf(buf
, size
, fmt
, args
);
1831 if (likely(i
< size
))
1837 EXPORT_SYMBOL(vscnprintf
);
1840 * snprintf - Format a string and place it in a buffer
1841 * @buf: The buffer to place the result into
1842 * @size: The size of the buffer, including the trailing null space
1843 * @fmt: The format string to use
1844 * @...: Arguments for the format string
1846 * The return value is the number of characters which would be
1847 * generated for the given input, excluding the trailing null,
1848 * as per ISO C99. If the return is greater than or equal to
1849 * @size, the resulting string is truncated.
1851 * See the vsnprintf() documentation for format string extensions over C99.
1853 int snprintf(char *buf
, size_t size
, const char *fmt
, ...)
1858 va_start(args
, fmt
);
1859 i
= vsnprintf(buf
, size
, fmt
, args
);
1864 EXPORT_SYMBOL(snprintf
);
1867 * scnprintf - Format a string and place it in a buffer
1868 * @buf: The buffer to place the result into
1869 * @size: The size of the buffer, including the trailing null space
1870 * @fmt: The format string to use
1871 * @...: Arguments for the format string
1873 * The return value is the number of characters written into @buf not including
1874 * the trailing '\0'. If @size is == 0 the function returns 0.
1877 int scnprintf(char *buf
, size_t size
, const char *fmt
, ...)
1882 va_start(args
, fmt
);
1883 i
= vscnprintf(buf
, size
, fmt
, args
);
1888 EXPORT_SYMBOL(scnprintf
);
1891 * vsprintf - Format a string and place it in a buffer
1892 * @buf: The buffer to place the result into
1893 * @fmt: The format string to use
1894 * @args: Arguments for the format string
1896 * The function returns the number of characters written
1897 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1900 * If you're not already dealing with a va_list consider using sprintf().
1902 * See the vsnprintf() documentation for format string extensions over C99.
1904 int vsprintf(char *buf
, const char *fmt
, va_list args
)
1906 return vsnprintf(buf
, INT_MAX
, fmt
, args
);
1908 EXPORT_SYMBOL(vsprintf
);
1911 * sprintf - Format a string and place it in a buffer
1912 * @buf: The buffer to place the result into
1913 * @fmt: The format string to use
1914 * @...: Arguments for the format string
1916 * The function returns the number of characters written
1917 * into @buf. Use snprintf() or scnprintf() in order to avoid
1920 * See the vsnprintf() documentation for format string extensions over C99.
1922 int sprintf(char *buf
, const char *fmt
, ...)
1927 va_start(args
, fmt
);
1928 i
= vsnprintf(buf
, INT_MAX
, fmt
, args
);
1933 EXPORT_SYMBOL(sprintf
);
1935 #ifdef CONFIG_BINARY_PRINTF
1938 * vbin_printf() - VA arguments to binary data
1939 * bstr_printf() - Binary data to text string
1943 * vbin_printf - Parse a format string and place args' binary value in a buffer
1944 * @bin_buf: The buffer to place args' binary value
1945 * @size: The size of the buffer(by words(32bits), not characters)
1946 * @fmt: The format string to use
1947 * @args: Arguments for the format string
1949 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1952 * The return value is the number of words(32bits) which would be generated for
1956 * If the return value is greater than @size, the resulting bin_buf is NOT
1957 * valid for bstr_printf().
1959 int vbin_printf(u32
*bin_buf
, size_t size
, const char *fmt
, va_list args
)
1961 struct printf_spec spec
= {0};
1964 str
= (char *)bin_buf
;
1965 end
= (char *)(bin_buf
+ size
);
1967 #define save_arg(type) \
1969 if (sizeof(type) == 8) { \
1970 unsigned long long value; \
1971 str = PTR_ALIGN(str, sizeof(u32)); \
1972 value = va_arg(args, unsigned long long); \
1973 if (str + sizeof(type) <= end) { \
1974 *(u32 *)str = *(u32 *)&value; \
1975 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1978 unsigned long value; \
1979 str = PTR_ALIGN(str, sizeof(type)); \
1980 value = va_arg(args, int); \
1981 if (str + sizeof(type) <= end) \
1982 *(typeof(type) *)str = (type)value; \
1984 str += sizeof(type); \
1988 int read
= format_decode(fmt
, &spec
);
1992 switch (spec
.type
) {
1993 case FORMAT_TYPE_NONE
:
1994 case FORMAT_TYPE_INVALID
:
1995 case FORMAT_TYPE_PERCENT_CHAR
:
1998 case FORMAT_TYPE_WIDTH
:
1999 case FORMAT_TYPE_PRECISION
:
2003 case FORMAT_TYPE_CHAR
:
2007 case FORMAT_TYPE_STR
: {
2008 const char *save_str
= va_arg(args
, char *);
2011 if ((unsigned long)save_str
> (unsigned long)-PAGE_SIZE
2012 || (unsigned long)save_str
< PAGE_SIZE
)
2013 save_str
= "(null)";
2014 len
= strlen(save_str
) + 1;
2015 if (str
+ len
< end
)
2016 memcpy(str
, save_str
, len
);
2021 case FORMAT_TYPE_PTR
:
2023 /* skip all alphanumeric pointer suffixes */
2024 while (isalnum(*fmt
))
2028 case FORMAT_TYPE_NRCHARS
: {
2029 /* skip %n 's argument */
2030 u8 qualifier
= spec
.qualifier
;
2032 if (qualifier
== 'l')
2033 skip_arg
= va_arg(args
, long *);
2034 else if (_tolower(qualifier
) == 'z')
2035 skip_arg
= va_arg(args
, size_t *);
2037 skip_arg
= va_arg(args
, int *);
2042 switch (spec
.type
) {
2044 case FORMAT_TYPE_LONG_LONG
:
2045 save_arg(long long);
2047 case FORMAT_TYPE_ULONG
:
2048 case FORMAT_TYPE_LONG
:
2049 save_arg(unsigned long);
2051 case FORMAT_TYPE_SIZE_T
:
2054 case FORMAT_TYPE_PTRDIFF
:
2055 save_arg(ptrdiff_t);
2057 case FORMAT_TYPE_UBYTE
:
2058 case FORMAT_TYPE_BYTE
:
2061 case FORMAT_TYPE_USHORT
:
2062 case FORMAT_TYPE_SHORT
:
2071 return (u32
*)(PTR_ALIGN(str
, sizeof(u32
))) - bin_buf
;
2074 EXPORT_SYMBOL_GPL(vbin_printf
);
2077 * bstr_printf - Format a string from binary arguments and place it in a buffer
2078 * @buf: The buffer to place the result into
2079 * @size: The size of the buffer, including the trailing null space
2080 * @fmt: The format string to use
2081 * @bin_buf: Binary arguments for the format string
2083 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2084 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2085 * a binary buffer that generated by vbin_printf.
2087 * The format follows C99 vsnprintf, but has some extensions:
2088 * see vsnprintf comment for details.
2090 * The return value is the number of characters which would
2091 * be generated for the given input, excluding the trailing
2092 * '\0', as per ISO C99. If you want to have the exact
2093 * number of characters written into @buf as return value
2094 * (not including the trailing '\0'), use vscnprintf(). If the
2095 * return is greater than or equal to @size, the resulting
2096 * string is truncated.
2098 int bstr_printf(char *buf
, size_t size
, const char *fmt
, const u32
*bin_buf
)
2100 struct printf_spec spec
= {0};
2102 const char *args
= (const char *)bin_buf
;
2104 if (WARN_ON_ONCE((int) size
< 0))
2110 #define get_arg(type) \
2112 typeof(type) value; \
2113 if (sizeof(type) == 8) { \
2114 args = PTR_ALIGN(args, sizeof(u32)); \
2115 *(u32 *)&value = *(u32 *)args; \
2116 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2118 args = PTR_ALIGN(args, sizeof(type)); \
2119 value = *(typeof(type) *)args; \
2121 args += sizeof(type); \
2125 /* Make sure end is always >= buf */
2132 const char *old_fmt
= fmt
;
2133 int read
= format_decode(fmt
, &spec
);
2137 switch (spec
.type
) {
2138 case FORMAT_TYPE_NONE
: {
2141 if (copy
> end
- str
)
2143 memcpy(str
, old_fmt
, copy
);
2149 case FORMAT_TYPE_WIDTH
:
2150 spec
.field_width
= get_arg(int);
2153 case FORMAT_TYPE_PRECISION
:
2154 spec
.precision
= get_arg(int);
2157 case FORMAT_TYPE_CHAR
: {
2160 if (!(spec
.flags
& LEFT
)) {
2161 while (--spec
.field_width
> 0) {
2167 c
= (unsigned char) get_arg(char);
2171 while (--spec
.field_width
> 0) {
2179 case FORMAT_TYPE_STR
: {
2180 const char *str_arg
= args
;
2181 args
+= strlen(str_arg
) + 1;
2182 str
= string(str
, end
, (char *)str_arg
, spec
);
2186 case FORMAT_TYPE_PTR
:
2187 str
= pointer(fmt
+1, str
, end
, get_arg(void *), spec
);
2188 while (isalnum(*fmt
))
2192 case FORMAT_TYPE_PERCENT_CHAR
:
2193 case FORMAT_TYPE_INVALID
:
2199 case FORMAT_TYPE_NRCHARS
:
2204 unsigned long long num
;
2206 switch (spec
.type
) {
2208 case FORMAT_TYPE_LONG_LONG
:
2209 num
= get_arg(long long);
2211 case FORMAT_TYPE_ULONG
:
2212 case FORMAT_TYPE_LONG
:
2213 num
= get_arg(unsigned long);
2215 case FORMAT_TYPE_SIZE_T
:
2216 num
= get_arg(size_t);
2218 case FORMAT_TYPE_PTRDIFF
:
2219 num
= get_arg(ptrdiff_t);
2221 case FORMAT_TYPE_UBYTE
:
2222 num
= get_arg(unsigned char);
2224 case FORMAT_TYPE_BYTE
:
2225 num
= get_arg(signed char);
2227 case FORMAT_TYPE_USHORT
:
2228 num
= get_arg(unsigned short);
2230 case FORMAT_TYPE_SHORT
:
2231 num
= get_arg(short);
2233 case FORMAT_TYPE_UINT
:
2234 num
= get_arg(unsigned int);
2240 str
= number(str
, end
, num
, spec
);
2242 } /* switch(spec.type) */
2254 /* the trailing null byte doesn't count towards the total */
2257 EXPORT_SYMBOL_GPL(bstr_printf
);
2260 * bprintf - Parse a format string and place args' binary value in a buffer
2261 * @bin_buf: The buffer to place args' binary value
2262 * @size: The size of the buffer(by words(32bits), not characters)
2263 * @fmt: The format string to use
2264 * @...: Arguments for the format string
2266 * The function returns the number of words(u32) written
2269 int bprintf(u32
*bin_buf
, size_t size
, const char *fmt
, ...)
2274 va_start(args
, fmt
);
2275 ret
= vbin_printf(bin_buf
, size
, fmt
, args
);
2280 EXPORT_SYMBOL_GPL(bprintf
);
2282 #endif /* CONFIG_BINARY_PRINTF */
2285 * vsscanf - Unformat a buffer into a list of arguments
2286 * @buf: input buffer
2287 * @fmt: format of buffer
2290 int vsscanf(const char *buf
, const char *fmt
, va_list args
)
2292 const char *str
= buf
;
2300 unsigned long long u
;
2306 /* skip any white space in format */
2307 /* white space in format matchs any amount of
2308 * white space, including none, in the input.
2310 if (isspace(*fmt
)) {
2311 fmt
= skip_spaces(++fmt
);
2312 str
= skip_spaces(str
);
2315 /* anything that is not a conversion must match exactly */
2316 if (*fmt
!= '%' && *fmt
) {
2317 if (*fmt
++ != *str
++)
2326 /* skip this conversion.
2327 * advance both strings to next white space
2332 while (!isspace(*fmt
) && *fmt
!= '%' && *fmt
)
2334 while (!isspace(*str
) && *str
)
2339 /* get field width */
2341 if (isdigit(*fmt
)) {
2342 field_width
= skip_atoi(&fmt
);
2343 if (field_width
<= 0)
2347 /* get conversion qualifier */
2349 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
2350 _tolower(*fmt
) == 'z') {
2352 if (unlikely(qualifier
== *fmt
)) {
2353 if (qualifier
== 'h') {
2356 } else if (qualifier
== 'l') {
2367 /* return number of characters read so far */
2368 *va_arg(args
, int *) = str
- buf
;
2382 char *s
= (char *)va_arg(args
, char*);
2383 if (field_width
== -1)
2387 } while (--field_width
> 0 && *str
);
2393 char *s
= (char *)va_arg(args
, char *);
2394 if (field_width
== -1)
2395 field_width
= SHRT_MAX
;
2396 /* first, skip leading white space in buffer */
2397 str
= skip_spaces(str
);
2399 /* now copy until next white space */
2400 while (*str
&& !isspace(*str
) && field_width
--)
2420 /* looking for '%' in str */
2425 /* invalid format; stop here */
2429 /* have some sort of integer conversion.
2430 * first, skip white space in buffer.
2432 str
= skip_spaces(str
);
2435 if (is_sign
&& digit
== '-')
2439 || (base
== 16 && !isxdigit(digit
))
2440 || (base
== 10 && !isdigit(digit
))
2441 || (base
== 8 && (!isdigit(digit
) || digit
> '7'))
2442 || (base
== 0 && !isdigit(digit
)))
2446 val
.s
= qualifier
!= 'L' ?
2447 simple_strtol(str
, &next
, base
) :
2448 simple_strtoll(str
, &next
, base
);
2450 val
.u
= qualifier
!= 'L' ?
2451 simple_strtoul(str
, &next
, base
) :
2452 simple_strtoull(str
, &next
, base
);
2454 if (field_width
> 0 && next
- str
> field_width
) {
2456 _parse_integer_fixup_radix(str
, &base
);
2457 while (next
- str
> field_width
) {
2459 val
.s
= div_s64(val
.s
, base
);
2461 val
.u
= div_u64(val
.u
, base
);
2466 switch (qualifier
) {
2467 case 'H': /* that's 'hh' in format */
2469 *va_arg(args
, signed char *) = val
.s
;
2471 *va_arg(args
, unsigned char *) = val
.u
;
2475 *va_arg(args
, short *) = val
.s
;
2477 *va_arg(args
, unsigned short *) = val
.u
;
2481 *va_arg(args
, long *) = val
.s
;
2483 *va_arg(args
, unsigned long *) = val
.u
;
2487 *va_arg(args
, long long *) = val
.s
;
2489 *va_arg(args
, unsigned long long *) = val
.u
;
2493 *va_arg(args
, size_t *) = val
.u
;
2497 *va_arg(args
, int *) = val
.s
;
2499 *va_arg(args
, unsigned int *) = val
.u
;
2511 EXPORT_SYMBOL(vsscanf
);
2514 * sscanf - Unformat a buffer into a list of arguments
2515 * @buf: input buffer
2516 * @fmt: formatting of buffer
2517 * @...: resulting arguments
2519 int sscanf(const char *buf
, const char *fmt
, ...)
2524 va_start(args
, fmt
);
2525 i
= vsscanf(buf
, fmt
, args
);
2530 EXPORT_SYMBOL(sscanf
);