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() */
36 #include <linux/string_helpers.h>
40 * simple_strtoull - convert a string to an unsigned long long
41 * @cp: The start of the string
42 * @endp: A pointer to the end of the parsed string will be placed here
43 * @base: The number base to use
45 * This function is obsolete. Please use kstrtoull instead.
47 unsigned long long simple_strtoull(const char *cp
, char **endp
, unsigned int base
)
49 unsigned long long result
;
52 cp
= _parse_integer_fixup_radix(cp
, &base
);
53 rv
= _parse_integer(cp
, base
, &result
);
55 cp
+= (rv
& ~KSTRTOX_OVERFLOW
);
62 EXPORT_SYMBOL(simple_strtoull
);
65 * simple_strtoul - convert a string to an unsigned long
66 * @cp: The start of the string
67 * @endp: A pointer to the end of the parsed string will be placed here
68 * @base: The number base to use
70 * This function is obsolete. Please use kstrtoul instead.
72 unsigned long simple_strtoul(const char *cp
, char **endp
, unsigned int base
)
74 return simple_strtoull(cp
, endp
, base
);
76 EXPORT_SYMBOL(simple_strtoul
);
79 * simple_strtol - convert a string to a signed long
80 * @cp: The start of the string
81 * @endp: A pointer to the end of the parsed string will be placed here
82 * @base: The number base to use
84 * This function is obsolete. Please use kstrtol instead.
86 long simple_strtol(const char *cp
, char **endp
, unsigned int base
)
89 return -simple_strtoul(cp
+ 1, endp
, base
);
91 return simple_strtoul(cp
, endp
, base
);
93 EXPORT_SYMBOL(simple_strtol
);
96 * simple_strtoll - convert a string to a signed long long
97 * @cp: The start of the string
98 * @endp: A pointer to the end of the parsed string will be placed here
99 * @base: The number base to use
101 * This function is obsolete. Please use kstrtoll instead.
103 long long simple_strtoll(const char *cp
, char **endp
, unsigned int base
)
106 return -simple_strtoull(cp
+ 1, endp
, base
);
108 return simple_strtoull(cp
, endp
, base
);
110 EXPORT_SYMBOL(simple_strtoll
);
112 static noinline_for_stack
113 int skip_atoi(const char **s
)
118 i
= i
*10 + *((*s
)++) - '0';
123 /* Decimal conversion is by far the most typical, and is used
124 * for /proc and /sys data. This directly impacts e.g. top performance
125 * with many processes running. We optimize it for speed
126 * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
127 * (with permission from the author, Douglas W. Jones).
130 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
131 /* Formats correctly any integer in [0, 999999999] */
132 static noinline_for_stack
133 char *put_dec_full9(char *buf
, unsigned q
)
138 * Possible ways to approx. divide by 10
139 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
140 * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul)
141 * (x * 0x6667) >> 18 x < 43699
142 * (x * 0x3334) >> 17 x < 16389
143 * (x * 0x199a) >> 16 x < 16389
144 * (x * 0x0ccd) >> 15 x < 16389
145 * (x * 0x0667) >> 14 x < 2739
146 * (x * 0x0334) >> 13 x < 1029
147 * (x * 0x019a) >> 12 x < 1029
148 * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386)
149 * (x * 0x0067) >> 10 x < 179
150 * (x * 0x0034) >> 9 x < 69 same
151 * (x * 0x001a) >> 8 x < 69 same
152 * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386)
153 * (x * 0x0007) >> 6 x < 19
154 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
156 r
= (q
* (uint64_t)0x1999999a) >> 32;
157 *buf
++ = (q
- 10 * r
) + '0'; /* 1 */
158 q
= (r
* (uint64_t)0x1999999a) >> 32;
159 *buf
++ = (r
- 10 * q
) + '0'; /* 2 */
160 r
= (q
* (uint64_t)0x1999999a) >> 32;
161 *buf
++ = (q
- 10 * r
) + '0'; /* 3 */
162 q
= (r
* (uint64_t)0x1999999a) >> 32;
163 *buf
++ = (r
- 10 * q
) + '0'; /* 4 */
164 r
= (q
* (uint64_t)0x1999999a) >> 32;
165 *buf
++ = (q
- 10 * r
) + '0'; /* 5 */
166 /* Now value is under 10000, can avoid 64-bit multiply */
167 q
= (r
* 0x199a) >> 16;
168 *buf
++ = (r
- 10 * q
) + '0'; /* 6 */
169 r
= (q
* 0xcd) >> 11;
170 *buf
++ = (q
- 10 * r
) + '0'; /* 7 */
171 q
= (r
* 0xcd) >> 11;
172 *buf
++ = (r
- 10 * q
) + '0'; /* 8 */
173 *buf
++ = q
+ '0'; /* 9 */
178 /* Similar to above but do not pad with zeros.
179 * Code can be easily arranged to print 9 digits too, but our callers
180 * always call put_dec_full9() instead when the number has 9 decimal digits.
182 static noinline_for_stack
183 char *put_dec_trunc8(char *buf
, unsigned r
)
187 /* Copy of previous function's body with added early returns */
190 r
= (r
* (uint64_t)0x1999999a) >> 32;
194 q
= (r
* 0x199a) >> 16; /* r <= 9999 */
195 *buf
++ = (r
- 10 * q
) + '0';
198 r
= (q
* 0xcd) >> 11; /* q <= 999 */
199 *buf
++ = (q
- 10 * r
) + '0';
202 q
= (r
* 0xcd) >> 11; /* r <= 99 */
203 *buf
++ = (r
- 10 * q
) + '0';
206 *buf
++ = q
+ '0'; /* q <= 9 */
210 /* There are two algorithms to print larger numbers.
211 * One is generic: divide by 1000000000 and repeatedly print
212 * groups of (up to) 9 digits. It's conceptually simple,
213 * but requires a (unsigned long long) / 1000000000 division.
215 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
216 * manipulates them cleverly and generates groups of 4 decimal digits.
217 * It so happens that it does NOT require long long division.
219 * If long is > 32 bits, division of 64-bit values is relatively easy,
220 * and we will use the first algorithm.
221 * If long long is > 64 bits (strange architecture with VERY large long long),
222 * second algorithm can't be used, and we again use the first one.
224 * Else (if long is 32 bits and long long is 64 bits) we use second one.
227 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
229 /* First algorithm: generic */
232 char *put_dec(char *buf
, unsigned long long n
)
234 if (n
>= 100*1000*1000) {
235 while (n
>= 1000*1000*1000)
236 buf
= put_dec_full9(buf
, do_div(n
, 1000*1000*1000));
237 if (n
>= 100*1000*1000)
238 return put_dec_full9(buf
, n
);
240 return put_dec_trunc8(buf
, n
);
245 /* Second algorithm: valid only for 64-bit long longs */
247 /* See comment in put_dec_full9 for choice of constants */
248 static noinline_for_stack
249 void put_dec_full4(char *buf
, unsigned q
)
252 r
= (q
* 0xccd) >> 15;
253 buf
[0] = (q
- 10 * r
) + '0';
254 q
= (r
* 0xcd) >> 11;
255 buf
[1] = (r
- 10 * q
) + '0';
256 r
= (q
* 0xcd) >> 11;
257 buf
[2] = (q
- 10 * r
) + '0';
262 * Call put_dec_full4 on x % 10000, return x / 10000.
263 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
264 * holds for all x < 1,128,869,999. The largest value this
265 * helper will ever be asked to convert is 1,125,520,955.
266 * (d1 in the put_dec code, assuming n is all-ones).
269 unsigned put_dec_helper4(char *buf
, unsigned x
)
271 uint32_t q
= (x
* (uint64_t)0x346DC5D7) >> 43;
273 put_dec_full4(buf
, x
- q
* 10000);
277 /* Based on code by Douglas W. Jones found at
278 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
279 * (with permission from the author).
280 * Performs no 64-bit division and hence should be fast on 32-bit machines.
283 char *put_dec(char *buf
, unsigned long long n
)
285 uint32_t d3
, d2
, d1
, q
, h
;
287 if (n
< 100*1000*1000)
288 return put_dec_trunc8(buf
, n
);
290 d1
= ((uint32_t)n
>> 16); /* implicit "& 0xffff" */
293 d3
= (h
>> 16); /* implicit "& 0xffff" */
295 q
= 656 * d3
+ 7296 * d2
+ 5536 * d1
+ ((uint32_t)n
& 0xffff);
296 q
= put_dec_helper4(buf
, q
);
298 q
+= 7671 * d3
+ 9496 * d2
+ 6 * d1
;
299 q
= put_dec_helper4(buf
+4, q
);
301 q
+= 4749 * d3
+ 42 * d2
;
302 q
= put_dec_helper4(buf
+8, q
);
307 buf
= put_dec_trunc8(buf
, q
);
308 else while (buf
[-1] == '0')
317 * Convert passed number to decimal string.
318 * Returns the length of string. On buffer overflow, returns 0.
320 * If speed is not important, use snprintf(). It's easy to read the code.
322 int num_to_str(char *buf
, int size
, unsigned long long num
)
324 char tmp
[sizeof(num
) * 3];
327 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
332 len
= put_dec(tmp
, num
) - tmp
;
337 for (idx
= 0; idx
< len
; ++idx
)
338 buf
[idx
] = tmp
[len
- idx
- 1];
342 #define ZEROPAD 1 /* pad with zero */
343 #define SIGN 2 /* unsigned/signed long */
344 #define PLUS 4 /* show plus */
345 #define SPACE 8 /* space if plus */
346 #define LEFT 16 /* left justified */
347 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
348 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
351 FORMAT_TYPE_NONE
, /* Just a string part */
353 FORMAT_TYPE_PRECISION
,
357 FORMAT_TYPE_PERCENT_CHAR
,
359 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 *escaped_string(char *buf
, char *end
, u8
*addr
, struct printf_spec spec
,
1110 unsigned int flags
= 0;
1113 if (spec
.field_width
== 0)
1114 return buf
; /* nothing to print */
1116 if (ZERO_OR_NULL_PTR(addr
))
1117 return string(buf
, end
, NULL
, spec
); /* NULL pointer */
1121 switch (fmt
[count
++]) {
1123 flags
|= ESCAPE_ANY
;
1126 flags
|= ESCAPE_SPECIAL
;
1129 flags
|= ESCAPE_HEX
;
1132 flags
|= ESCAPE_NULL
;
1135 flags
|= ESCAPE_OCTAL
;
1141 flags
|= ESCAPE_SPACE
;
1150 flags
= ESCAPE_ANY_NP
;
1152 len
= spec
.field_width
< 0 ? 1 : spec
.field_width
;
1154 /* Ignore the error. We print as many characters as we can */
1155 string_escape_mem(addr
, len
, &buf
, end
- buf
, flags
, NULL
);
1160 static noinline_for_stack
1161 char *uuid_string(char *buf
, char *end
, const u8
*addr
,
1162 struct printf_spec spec
, const char *fmt
)
1164 char uuid
[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1167 static const u8 be
[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1168 static const u8 le
[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1169 const u8
*index
= be
;
1174 uc
= true; /* fall-through */
1183 for (i
= 0; i
< 16; i
++) {
1184 p
= hex_byte_pack(p
, addr
[index
[i
]]);
1204 return string(buf
, end
, uuid
, spec
);
1208 char *netdev_feature_string(char *buf
, char *end
, const u8
*addr
,
1209 struct printf_spec spec
)
1211 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
1212 if (spec
.field_width
== -1)
1213 spec
.field_width
= 2 + 2 * sizeof(netdev_features_t
);
1216 return number(buf
, end
, *(const netdev_features_t
*)addr
, spec
);
1219 static noinline_for_stack
1220 char *address_val(char *buf
, char *end
, const void *addr
,
1221 struct printf_spec spec
, const char *fmt
)
1223 unsigned long long num
;
1225 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
1230 num
= *(const dma_addr_t
*)addr
;
1231 spec
.field_width
= sizeof(dma_addr_t
) * 2 + 2;
1235 num
= *(const phys_addr_t
*)addr
;
1236 spec
.field_width
= sizeof(phys_addr_t
) * 2 + 2;
1240 return number(buf
, end
, num
, spec
);
1243 int kptr_restrict __read_mostly
;
1246 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1247 * by an extra set of alphanumeric characters that are extended format
1250 * Right now we handle:
1252 * - 'F' For symbolic function descriptor pointers with offset
1253 * - 'f' For simple symbolic function names without offset
1254 * - 'S' For symbolic direct pointers with offset
1255 * - 's' For symbolic direct pointers without offset
1256 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1257 * - 'B' For backtraced symbolic direct pointers with offset
1258 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1259 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1260 * - 'M' For a 6-byte MAC address, it prints the address in the
1261 * usual colon-separated hex notation
1262 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1263 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1264 * with a dash-separated hex notation
1265 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1266 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1267 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1268 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1270 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1271 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1272 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1273 * IPv6 omits the colons (01020304...0f)
1274 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1276 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1277 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1278 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1279 * - 'I[6S]c' for IPv6 addresses printed as specified by
1280 * http://tools.ietf.org/html/rfc5952
1281 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1282 * of the following flags (see string_escape_mem() for the
1285 * c - ESCAPE_SPECIAL
1291 * By default ESCAPE_ANY_NP is used.
1292 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1293 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1294 * Options for %pU are:
1295 * b big endian lower case hex (default)
1296 * B big endian UPPER case hex
1297 * l little endian lower case hex
1298 * L little endian UPPER case hex
1299 * big endian output byte order is:
1300 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1301 * little endian output byte order is:
1302 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1303 * - 'V' For a struct va_format which contains a format string * and va_list *,
1304 * call vsnprintf(->format, *->va_list).
1305 * Implements a "recursive vsnprintf".
1306 * Do not use this feature without some mechanism to verify the
1307 * correctness of the format string and va_list arguments.
1308 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1309 * - 'NF' For a netdev_features_t
1310 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1311 * a certain separator (' ' by default):
1315 * The maximum supported length is 64 bytes of the input. Consider
1316 * to use print_hex_dump() for the larger input.
1317 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1318 * (default assumed to be phys_addr_t, passed by reference)
1319 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1320 * - 'D[234]' Same as 'd' but for a struct file
1322 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1323 * function pointers are really function descriptors, which contain a
1324 * pointer to the real address.
1326 static noinline_for_stack
1327 char *pointer(const char *fmt
, char *buf
, char *end
, void *ptr
,
1328 struct printf_spec spec
)
1330 int default_width
= 2 * sizeof(void *) + (spec
.flags
& SPECIAL
? 2 : 0);
1332 if (!ptr
&& *fmt
!= 'K') {
1334 * Print (null) with the same width as a pointer so it makes
1335 * tabular output look nice.
1337 if (spec
.field_width
== -1)
1338 spec
.field_width
= default_width
;
1339 return string(buf
, end
, "(null)", spec
);
1345 ptr
= dereference_function_descriptor(ptr
);
1350 return symbol_string(buf
, end
, ptr
, spec
, fmt
);
1353 return resource_string(buf
, end
, ptr
, spec
, fmt
);
1355 return hex_string(buf
, end
, ptr
, spec
, fmt
);
1356 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1357 case 'm': /* Contiguous: 000102030405 */
1359 /* [mM]R (Reverse order; Bluetooth) */
1360 return mac_address_string(buf
, end
, ptr
, spec
, fmt
);
1361 case 'I': /* Formatted IP supported
1363 * 6: 0001:0203:...:0708
1364 * 6c: 1::708 or 1::1.2.3.4
1366 case 'i': /* Contiguous:
1367 * 4: 001.002.003.004
1372 return ip6_addr_string(buf
, end
, ptr
, spec
, fmt
);
1374 return ip4_addr_string(buf
, end
, ptr
, spec
, fmt
);
1377 struct sockaddr raw
;
1378 struct sockaddr_in v4
;
1379 struct sockaddr_in6 v6
;
1382 switch (sa
->raw
.sa_family
) {
1384 return ip4_addr_string_sa(buf
, end
, &sa
->v4
, spec
, fmt
);
1386 return ip6_addr_string_sa(buf
, end
, &sa
->v6
, spec
, fmt
);
1388 return string(buf
, end
, "(invalid address)", spec
);
1393 return escaped_string(buf
, end
, ptr
, spec
, fmt
);
1395 return uuid_string(buf
, end
, ptr
, spec
, fmt
);
1400 va_copy(va
, *((struct va_format
*)ptr
)->va
);
1401 buf
+= vsnprintf(buf
, end
> buf
? end
- buf
: 0,
1402 ((struct va_format
*)ptr
)->fmt
, va
);
1408 * %pK cannot be used in IRQ context because its test
1409 * for CAP_SYSLOG would be meaningless.
1411 if (kptr_restrict
&& (in_irq() || in_serving_softirq() ||
1413 if (spec
.field_width
== -1)
1414 spec
.field_width
= default_width
;
1415 return string(buf
, end
, "pK-error", spec
);
1418 switch (kptr_restrict
) {
1420 /* Always print %pK values */
1424 * Only print the real pointer value if the current
1425 * process has CAP_SYSLOG and is running with the
1426 * same credentials it started with. This is because
1427 * access to files is checked at open() time, but %pK
1428 * checks permission at read() time. We don't want to
1429 * leak pointer values if a binary opens a file using
1430 * %pK and then elevates privileges before reading it.
1432 const struct cred
*cred
= current_cred();
1434 if (!has_capability_noaudit(current
, CAP_SYSLOG
) ||
1435 !uid_eq(cred
->euid
, cred
->uid
) ||
1436 !gid_eq(cred
->egid
, cred
->gid
))
1442 /* Always print 0's for %pK */
1451 return netdev_feature_string(buf
, end
, ptr
, spec
);
1455 return address_val(buf
, end
, ptr
, spec
, fmt
);
1457 return dentry_name(buf
, end
, ptr
, spec
, fmt
);
1459 return dentry_name(buf
, end
,
1460 ((const struct file
*)ptr
)->f_path
.dentry
,
1463 spec
.flags
|= SMALL
;
1464 if (spec
.field_width
== -1) {
1465 spec
.field_width
= default_width
;
1466 spec
.flags
|= ZEROPAD
;
1470 return number(buf
, end
, (unsigned long) ptr
, spec
);
1474 * Helper function to decode printf style format.
1475 * Each call decode a token from the format and return the
1476 * number of characters read (or likely the delta where it wants
1477 * to go on the next call).
1478 * The decoded token is returned through the parameters
1480 * 'h', 'l', or 'L' for integer fields
1481 * 'z' support added 23/7/1999 S.H.
1482 * 'z' changed to 'Z' --davidm 1/25/99
1483 * 't' added for ptrdiff_t
1485 * @fmt: the format string
1486 * @type of the token returned
1487 * @flags: various flags such as +, -, # tokens..
1488 * @field_width: overwritten width
1489 * @base: base of the number (octal, hex, ...)
1490 * @precision: precision of a number
1491 * @qualifier: qualifier of a number (long, size_t, ...)
1493 static noinline_for_stack
1494 int format_decode(const char *fmt
, struct printf_spec
*spec
)
1496 const char *start
= fmt
;
1498 /* we finished early by reading the field width */
1499 if (spec
->type
== FORMAT_TYPE_WIDTH
) {
1500 if (spec
->field_width
< 0) {
1501 spec
->field_width
= -spec
->field_width
;
1502 spec
->flags
|= LEFT
;
1504 spec
->type
= FORMAT_TYPE_NONE
;
1508 /* we finished early by reading the precision */
1509 if (spec
->type
== FORMAT_TYPE_PRECISION
) {
1510 if (spec
->precision
< 0)
1511 spec
->precision
= 0;
1513 spec
->type
= FORMAT_TYPE_NONE
;
1518 spec
->type
= FORMAT_TYPE_NONE
;
1520 for (; *fmt
; ++fmt
) {
1525 /* Return the current non-format string */
1526 if (fmt
!= start
|| !*fmt
)
1532 while (1) { /* this also skips first '%' */
1538 case '-': spec
->flags
|= LEFT
; break;
1539 case '+': spec
->flags
|= PLUS
; break;
1540 case ' ': spec
->flags
|= SPACE
; break;
1541 case '#': spec
->flags
|= SPECIAL
; break;
1542 case '0': spec
->flags
|= ZEROPAD
; break;
1543 default: found
= false;
1550 /* get field width */
1551 spec
->field_width
= -1;
1554 spec
->field_width
= skip_atoi(&fmt
);
1555 else if (*fmt
== '*') {
1556 /* it's the next argument */
1557 spec
->type
= FORMAT_TYPE_WIDTH
;
1558 return ++fmt
- start
;
1562 /* get the precision */
1563 spec
->precision
= -1;
1566 if (isdigit(*fmt
)) {
1567 spec
->precision
= skip_atoi(&fmt
);
1568 if (spec
->precision
< 0)
1569 spec
->precision
= 0;
1570 } else if (*fmt
== '*') {
1571 /* it's the next argument */
1572 spec
->type
= FORMAT_TYPE_PRECISION
;
1573 return ++fmt
- start
;
1578 /* get the conversion qualifier */
1579 spec
->qualifier
= -1;
1580 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
1581 _tolower(*fmt
) == 'z' || *fmt
== 't') {
1582 spec
->qualifier
= *fmt
++;
1583 if (unlikely(spec
->qualifier
== *fmt
)) {
1584 if (spec
->qualifier
== 'l') {
1585 spec
->qualifier
= 'L';
1587 } else if (spec
->qualifier
== 'h') {
1588 spec
->qualifier
= 'H';
1598 spec
->type
= FORMAT_TYPE_CHAR
;
1599 return ++fmt
- start
;
1602 spec
->type
= FORMAT_TYPE_STR
;
1603 return ++fmt
- start
;
1606 spec
->type
= FORMAT_TYPE_PTR
;
1611 spec
->type
= FORMAT_TYPE_PERCENT_CHAR
;
1612 return ++fmt
- start
;
1614 /* integer number formats - set up the flags and "break" */
1620 spec
->flags
|= SMALL
;
1628 spec
->flags
|= SIGN
;
1634 * Since %n poses a greater security risk than utility, treat
1635 * it as an invalid format specifier. Warn about its use so
1636 * that new instances don't get added.
1638 WARN_ONCE(1, "Please remove ignored %%n in '%s'\n", fmt
);
1642 spec
->type
= FORMAT_TYPE_INVALID
;
1646 if (spec
->qualifier
== 'L')
1647 spec
->type
= FORMAT_TYPE_LONG_LONG
;
1648 else if (spec
->qualifier
== 'l') {
1649 if (spec
->flags
& SIGN
)
1650 spec
->type
= FORMAT_TYPE_LONG
;
1652 spec
->type
= FORMAT_TYPE_ULONG
;
1653 } else if (_tolower(spec
->qualifier
) == 'z') {
1654 spec
->type
= FORMAT_TYPE_SIZE_T
;
1655 } else if (spec
->qualifier
== 't') {
1656 spec
->type
= FORMAT_TYPE_PTRDIFF
;
1657 } else if (spec
->qualifier
== 'H') {
1658 if (spec
->flags
& SIGN
)
1659 spec
->type
= FORMAT_TYPE_BYTE
;
1661 spec
->type
= FORMAT_TYPE_UBYTE
;
1662 } else if (spec
->qualifier
== 'h') {
1663 if (spec
->flags
& SIGN
)
1664 spec
->type
= FORMAT_TYPE_SHORT
;
1666 spec
->type
= FORMAT_TYPE_USHORT
;
1668 if (spec
->flags
& SIGN
)
1669 spec
->type
= FORMAT_TYPE_INT
;
1671 spec
->type
= FORMAT_TYPE_UINT
;
1674 return ++fmt
- start
;
1678 * vsnprintf - Format a string and place it in a buffer
1679 * @buf: The buffer to place the result into
1680 * @size: The size of the buffer, including the trailing null space
1681 * @fmt: The format string to use
1682 * @args: Arguments for the format string
1684 * This function follows C99 vsnprintf, but has some extensions:
1685 * %pS output the name of a text symbol with offset
1686 * %ps output the name of a text symbol without offset
1687 * %pF output the name of a function pointer with its offset
1688 * %pf output the name of a function pointer without its offset
1689 * %pB output the name of a backtrace symbol with its offset
1690 * %pR output the address range in a struct resource with decoded flags
1691 * %pr output the address range in a struct resource with raw flags
1692 * %pM output a 6-byte MAC address with colons
1693 * %pMR output a 6-byte MAC address with colons in reversed order
1694 * %pMF output a 6-byte MAC address with dashes
1695 * %pm output a 6-byte MAC address without colons
1696 * %pmR output a 6-byte MAC address without colons in reversed order
1697 * %pI4 print an IPv4 address without leading zeros
1698 * %pi4 print an IPv4 address with leading zeros
1699 * %pI6 print an IPv6 address with colons
1700 * %pi6 print an IPv6 address without colons
1701 * %pI6c print an IPv6 address as specified by RFC 5952
1702 * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1703 * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1704 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1706 * %*pE[achnops] print an escaped buffer
1707 * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1708 * bytes of the input)
1711 * ** Please update Documentation/printk-formats.txt when making changes **
1713 * The return value is the number of characters which would
1714 * be generated for the given input, excluding the trailing
1715 * '\0', as per ISO C99. If you want to have the exact
1716 * number of characters written into @buf as return value
1717 * (not including the trailing '\0'), use vscnprintf(). If the
1718 * return is greater than or equal to @size, the resulting
1719 * string is truncated.
1721 * If you're not already dealing with a va_list consider using snprintf().
1723 int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1725 unsigned long long num
;
1727 struct printf_spec spec
= {0};
1729 /* Reject out-of-range values early. Large positive sizes are
1730 used for unknown buffer sizes. */
1731 if (WARN_ON_ONCE((int) size
< 0))
1737 /* Make sure end is always >= buf */
1744 const char *old_fmt
= fmt
;
1745 int read
= format_decode(fmt
, &spec
);
1749 switch (spec
.type
) {
1750 case FORMAT_TYPE_NONE
: {
1753 if (copy
> end
- str
)
1755 memcpy(str
, old_fmt
, copy
);
1761 case FORMAT_TYPE_WIDTH
:
1762 spec
.field_width
= va_arg(args
, int);
1765 case FORMAT_TYPE_PRECISION
:
1766 spec
.precision
= va_arg(args
, int);
1769 case FORMAT_TYPE_CHAR
: {
1772 if (!(spec
.flags
& LEFT
)) {
1773 while (--spec
.field_width
> 0) {
1780 c
= (unsigned char) va_arg(args
, int);
1784 while (--spec
.field_width
> 0) {
1792 case FORMAT_TYPE_STR
:
1793 str
= string(str
, end
, va_arg(args
, char *), spec
);
1796 case FORMAT_TYPE_PTR
:
1797 str
= pointer(fmt
+1, str
, end
, va_arg(args
, void *),
1799 while (isalnum(*fmt
))
1803 case FORMAT_TYPE_PERCENT_CHAR
:
1809 case FORMAT_TYPE_INVALID
:
1816 switch (spec
.type
) {
1817 case FORMAT_TYPE_LONG_LONG
:
1818 num
= va_arg(args
, long long);
1820 case FORMAT_TYPE_ULONG
:
1821 num
= va_arg(args
, unsigned long);
1823 case FORMAT_TYPE_LONG
:
1824 num
= va_arg(args
, long);
1826 case FORMAT_TYPE_SIZE_T
:
1827 if (spec
.flags
& SIGN
)
1828 num
= va_arg(args
, ssize_t
);
1830 num
= va_arg(args
, size_t);
1832 case FORMAT_TYPE_PTRDIFF
:
1833 num
= va_arg(args
, ptrdiff_t);
1835 case FORMAT_TYPE_UBYTE
:
1836 num
= (unsigned char) va_arg(args
, int);
1838 case FORMAT_TYPE_BYTE
:
1839 num
= (signed char) va_arg(args
, int);
1841 case FORMAT_TYPE_USHORT
:
1842 num
= (unsigned short) va_arg(args
, int);
1844 case FORMAT_TYPE_SHORT
:
1845 num
= (short) va_arg(args
, int);
1847 case FORMAT_TYPE_INT
:
1848 num
= (int) va_arg(args
, int);
1851 num
= va_arg(args
, unsigned int);
1854 str
= number(str
, end
, num
, spec
);
1865 /* the trailing null byte doesn't count towards the total */
1869 EXPORT_SYMBOL(vsnprintf
);
1872 * vscnprintf - Format a string and place it in a buffer
1873 * @buf: The buffer to place the result into
1874 * @size: The size of the buffer, including the trailing null space
1875 * @fmt: The format string to use
1876 * @args: Arguments for the format string
1878 * The return value is the number of characters which have been written into
1879 * the @buf not including the trailing '\0'. If @size is == 0 the function
1882 * If you're not already dealing with a va_list consider using scnprintf().
1884 * See the vsnprintf() documentation for format string extensions over C99.
1886 int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1890 i
= vsnprintf(buf
, size
, fmt
, args
);
1892 if (likely(i
< size
))
1898 EXPORT_SYMBOL(vscnprintf
);
1901 * snprintf - Format a string and place it in a buffer
1902 * @buf: The buffer to place the result into
1903 * @size: The size of the buffer, including the trailing null space
1904 * @fmt: The format string to use
1905 * @...: Arguments for the format string
1907 * The return value is the number of characters which would be
1908 * generated for the given input, excluding the trailing null,
1909 * as per ISO C99. If the return is greater than or equal to
1910 * @size, the resulting string is truncated.
1912 * See the vsnprintf() documentation for format string extensions over C99.
1914 int snprintf(char *buf
, size_t size
, const char *fmt
, ...)
1919 va_start(args
, fmt
);
1920 i
= vsnprintf(buf
, size
, fmt
, args
);
1925 EXPORT_SYMBOL(snprintf
);
1928 * scnprintf - Format a string and place it in a buffer
1929 * @buf: The buffer to place the result into
1930 * @size: The size of the buffer, including the trailing null space
1931 * @fmt: The format string to use
1932 * @...: Arguments for the format string
1934 * The return value is the number of characters written into @buf not including
1935 * the trailing '\0'. If @size is == 0 the function returns 0.
1938 int scnprintf(char *buf
, size_t size
, const char *fmt
, ...)
1943 va_start(args
, fmt
);
1944 i
= vscnprintf(buf
, size
, fmt
, args
);
1949 EXPORT_SYMBOL(scnprintf
);
1952 * vsprintf - Format a string and place it in a buffer
1953 * @buf: The buffer to place the result into
1954 * @fmt: The format string to use
1955 * @args: Arguments for the format string
1957 * The function returns the number of characters written
1958 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1961 * If you're not already dealing with a va_list consider using sprintf().
1963 * See the vsnprintf() documentation for format string extensions over C99.
1965 int vsprintf(char *buf
, const char *fmt
, va_list args
)
1967 return vsnprintf(buf
, INT_MAX
, fmt
, args
);
1969 EXPORT_SYMBOL(vsprintf
);
1972 * sprintf - Format a string and place it in a buffer
1973 * @buf: The buffer to place the result into
1974 * @fmt: The format string to use
1975 * @...: Arguments for the format string
1977 * The function returns the number of characters written
1978 * into @buf. Use snprintf() or scnprintf() in order to avoid
1981 * See the vsnprintf() documentation for format string extensions over C99.
1983 int sprintf(char *buf
, const char *fmt
, ...)
1988 va_start(args
, fmt
);
1989 i
= vsnprintf(buf
, INT_MAX
, fmt
, args
);
1994 EXPORT_SYMBOL(sprintf
);
1996 #ifdef CONFIG_BINARY_PRINTF
1999 * vbin_printf() - VA arguments to binary data
2000 * bstr_printf() - Binary data to text string
2004 * vbin_printf - Parse a format string and place args' binary value in a buffer
2005 * @bin_buf: The buffer to place args' binary value
2006 * @size: The size of the buffer(by words(32bits), not characters)
2007 * @fmt: The format string to use
2008 * @args: Arguments for the format string
2010 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2013 * The return value is the number of words(32bits) which would be generated for
2017 * If the return value is greater than @size, the resulting bin_buf is NOT
2018 * valid for bstr_printf().
2020 int vbin_printf(u32
*bin_buf
, size_t size
, const char *fmt
, va_list args
)
2022 struct printf_spec spec
= {0};
2025 str
= (char *)bin_buf
;
2026 end
= (char *)(bin_buf
+ size
);
2028 #define save_arg(type) \
2030 if (sizeof(type) == 8) { \
2031 unsigned long long value; \
2032 str = PTR_ALIGN(str, sizeof(u32)); \
2033 value = va_arg(args, unsigned long long); \
2034 if (str + sizeof(type) <= end) { \
2035 *(u32 *)str = *(u32 *)&value; \
2036 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2039 unsigned long value; \
2040 str = PTR_ALIGN(str, sizeof(type)); \
2041 value = va_arg(args, int); \
2042 if (str + sizeof(type) <= end) \
2043 *(typeof(type) *)str = (type)value; \
2045 str += sizeof(type); \
2049 int read
= format_decode(fmt
, &spec
);
2053 switch (spec
.type
) {
2054 case FORMAT_TYPE_NONE
:
2055 case FORMAT_TYPE_INVALID
:
2056 case FORMAT_TYPE_PERCENT_CHAR
:
2059 case FORMAT_TYPE_WIDTH
:
2060 case FORMAT_TYPE_PRECISION
:
2064 case FORMAT_TYPE_CHAR
:
2068 case FORMAT_TYPE_STR
: {
2069 const char *save_str
= va_arg(args
, char *);
2072 if ((unsigned long)save_str
> (unsigned long)-PAGE_SIZE
2073 || (unsigned long)save_str
< PAGE_SIZE
)
2074 save_str
= "(null)";
2075 len
= strlen(save_str
) + 1;
2076 if (str
+ len
< end
)
2077 memcpy(str
, save_str
, len
);
2082 case FORMAT_TYPE_PTR
:
2084 /* skip all alphanumeric pointer suffixes */
2085 while (isalnum(*fmt
))
2090 switch (spec
.type
) {
2092 case FORMAT_TYPE_LONG_LONG
:
2093 save_arg(long long);
2095 case FORMAT_TYPE_ULONG
:
2096 case FORMAT_TYPE_LONG
:
2097 save_arg(unsigned long);
2099 case FORMAT_TYPE_SIZE_T
:
2102 case FORMAT_TYPE_PTRDIFF
:
2103 save_arg(ptrdiff_t);
2105 case FORMAT_TYPE_UBYTE
:
2106 case FORMAT_TYPE_BYTE
:
2109 case FORMAT_TYPE_USHORT
:
2110 case FORMAT_TYPE_SHORT
:
2119 return (u32
*)(PTR_ALIGN(str
, sizeof(u32
))) - bin_buf
;
2122 EXPORT_SYMBOL_GPL(vbin_printf
);
2125 * bstr_printf - Format a string from binary arguments and place it in a buffer
2126 * @buf: The buffer to place the result into
2127 * @size: The size of the buffer, including the trailing null space
2128 * @fmt: The format string to use
2129 * @bin_buf: Binary arguments for the format string
2131 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2132 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2133 * a binary buffer that generated by vbin_printf.
2135 * The format follows C99 vsnprintf, but has some extensions:
2136 * see vsnprintf comment for details.
2138 * The return value is the number of characters which would
2139 * be generated for the given input, excluding the trailing
2140 * '\0', as per ISO C99. If you want to have the exact
2141 * number of characters written into @buf as return value
2142 * (not including the trailing '\0'), use vscnprintf(). If the
2143 * return is greater than or equal to @size, the resulting
2144 * string is truncated.
2146 int bstr_printf(char *buf
, size_t size
, const char *fmt
, const u32
*bin_buf
)
2148 struct printf_spec spec
= {0};
2150 const char *args
= (const char *)bin_buf
;
2152 if (WARN_ON_ONCE((int) size
< 0))
2158 #define get_arg(type) \
2160 typeof(type) value; \
2161 if (sizeof(type) == 8) { \
2162 args = PTR_ALIGN(args, sizeof(u32)); \
2163 *(u32 *)&value = *(u32 *)args; \
2164 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2166 args = PTR_ALIGN(args, sizeof(type)); \
2167 value = *(typeof(type) *)args; \
2169 args += sizeof(type); \
2173 /* Make sure end is always >= buf */
2180 const char *old_fmt
= fmt
;
2181 int read
= format_decode(fmt
, &spec
);
2185 switch (spec
.type
) {
2186 case FORMAT_TYPE_NONE
: {
2189 if (copy
> end
- str
)
2191 memcpy(str
, old_fmt
, copy
);
2197 case FORMAT_TYPE_WIDTH
:
2198 spec
.field_width
= get_arg(int);
2201 case FORMAT_TYPE_PRECISION
:
2202 spec
.precision
= get_arg(int);
2205 case FORMAT_TYPE_CHAR
: {
2208 if (!(spec
.flags
& LEFT
)) {
2209 while (--spec
.field_width
> 0) {
2215 c
= (unsigned char) get_arg(char);
2219 while (--spec
.field_width
> 0) {
2227 case FORMAT_TYPE_STR
: {
2228 const char *str_arg
= args
;
2229 args
+= strlen(str_arg
) + 1;
2230 str
= string(str
, end
, (char *)str_arg
, spec
);
2234 case FORMAT_TYPE_PTR
:
2235 str
= pointer(fmt
+1, str
, end
, get_arg(void *), spec
);
2236 while (isalnum(*fmt
))
2240 case FORMAT_TYPE_PERCENT_CHAR
:
2241 case FORMAT_TYPE_INVALID
:
2248 unsigned long long num
;
2250 switch (spec
.type
) {
2252 case FORMAT_TYPE_LONG_LONG
:
2253 num
= get_arg(long long);
2255 case FORMAT_TYPE_ULONG
:
2256 case FORMAT_TYPE_LONG
:
2257 num
= get_arg(unsigned long);
2259 case FORMAT_TYPE_SIZE_T
:
2260 num
= get_arg(size_t);
2262 case FORMAT_TYPE_PTRDIFF
:
2263 num
= get_arg(ptrdiff_t);
2265 case FORMAT_TYPE_UBYTE
:
2266 num
= get_arg(unsigned char);
2268 case FORMAT_TYPE_BYTE
:
2269 num
= get_arg(signed char);
2271 case FORMAT_TYPE_USHORT
:
2272 num
= get_arg(unsigned short);
2274 case FORMAT_TYPE_SHORT
:
2275 num
= get_arg(short);
2277 case FORMAT_TYPE_UINT
:
2278 num
= get_arg(unsigned int);
2284 str
= number(str
, end
, num
, spec
);
2286 } /* switch(spec.type) */
2298 /* the trailing null byte doesn't count towards the total */
2301 EXPORT_SYMBOL_GPL(bstr_printf
);
2304 * bprintf - Parse a format string and place args' binary value in a buffer
2305 * @bin_buf: The buffer to place args' binary value
2306 * @size: The size of the buffer(by words(32bits), not characters)
2307 * @fmt: The format string to use
2308 * @...: Arguments for the format string
2310 * The function returns the number of words(u32) written
2313 int bprintf(u32
*bin_buf
, size_t size
, const char *fmt
, ...)
2318 va_start(args
, fmt
);
2319 ret
= vbin_printf(bin_buf
, size
, fmt
, args
);
2324 EXPORT_SYMBOL_GPL(bprintf
);
2326 #endif /* CONFIG_BINARY_PRINTF */
2329 * vsscanf - Unformat a buffer into a list of arguments
2330 * @buf: input buffer
2331 * @fmt: format of buffer
2334 int vsscanf(const char *buf
, const char *fmt
, va_list args
)
2336 const char *str
= buf
;
2344 unsigned long long u
;
2350 /* skip any white space in format */
2351 /* white space in format matchs any amount of
2352 * white space, including none, in the input.
2354 if (isspace(*fmt
)) {
2355 fmt
= skip_spaces(++fmt
);
2356 str
= skip_spaces(str
);
2359 /* anything that is not a conversion must match exactly */
2360 if (*fmt
!= '%' && *fmt
) {
2361 if (*fmt
++ != *str
++)
2370 /* skip this conversion.
2371 * advance both strings to next white space
2376 while (!isspace(*fmt
) && *fmt
!= '%' && *fmt
)
2378 while (!isspace(*str
) && *str
)
2383 /* get field width */
2385 if (isdigit(*fmt
)) {
2386 field_width
= skip_atoi(&fmt
);
2387 if (field_width
<= 0)
2391 /* get conversion qualifier */
2393 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
2394 _tolower(*fmt
) == 'z') {
2396 if (unlikely(qualifier
== *fmt
)) {
2397 if (qualifier
== 'h') {
2400 } else if (qualifier
== 'l') {
2411 /* return number of characters read so far */
2412 *va_arg(args
, int *) = str
- buf
;
2426 char *s
= (char *)va_arg(args
, char*);
2427 if (field_width
== -1)
2431 } while (--field_width
> 0 && *str
);
2437 char *s
= (char *)va_arg(args
, char *);
2438 if (field_width
== -1)
2439 field_width
= SHRT_MAX
;
2440 /* first, skip leading white space in buffer */
2441 str
= skip_spaces(str
);
2443 /* now copy until next white space */
2444 while (*str
&& !isspace(*str
) && field_width
--)
2464 /* looking for '%' in str */
2469 /* invalid format; stop here */
2473 /* have some sort of integer conversion.
2474 * first, skip white space in buffer.
2476 str
= skip_spaces(str
);
2479 if (is_sign
&& digit
== '-')
2483 || (base
== 16 && !isxdigit(digit
))
2484 || (base
== 10 && !isdigit(digit
))
2485 || (base
== 8 && (!isdigit(digit
) || digit
> '7'))
2486 || (base
== 0 && !isdigit(digit
)))
2490 val
.s
= qualifier
!= 'L' ?
2491 simple_strtol(str
, &next
, base
) :
2492 simple_strtoll(str
, &next
, base
);
2494 val
.u
= qualifier
!= 'L' ?
2495 simple_strtoul(str
, &next
, base
) :
2496 simple_strtoull(str
, &next
, base
);
2498 if (field_width
> 0 && next
- str
> field_width
) {
2500 _parse_integer_fixup_radix(str
, &base
);
2501 while (next
- str
> field_width
) {
2503 val
.s
= div_s64(val
.s
, base
);
2505 val
.u
= div_u64(val
.u
, base
);
2510 switch (qualifier
) {
2511 case 'H': /* that's 'hh' in format */
2513 *va_arg(args
, signed char *) = val
.s
;
2515 *va_arg(args
, unsigned char *) = val
.u
;
2519 *va_arg(args
, short *) = val
.s
;
2521 *va_arg(args
, unsigned short *) = val
.u
;
2525 *va_arg(args
, long *) = val
.s
;
2527 *va_arg(args
, unsigned long *) = val
.u
;
2531 *va_arg(args
, long long *) = val
.s
;
2533 *va_arg(args
, unsigned long long *) = val
.u
;
2537 *va_arg(args
, size_t *) = val
.u
;
2541 *va_arg(args
, int *) = val
.s
;
2543 *va_arg(args
, unsigned int *) = val
.u
;
2555 EXPORT_SYMBOL(vsscanf
);
2558 * sscanf - Unformat a buffer into a list of arguments
2559 * @buf: input buffer
2560 * @fmt: formatting of buffer
2561 * @...: resulting arguments
2563 int sscanf(const char *buf
, const char *fmt
, ...)
2568 va_start(args
, fmt
);
2569 i
= vsscanf(buf
, fmt
, args
);
2574 EXPORT_SYMBOL(sscanf
);