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>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/uaccess.h>
27 #include <linux/ioport.h>
28 #include <net/addrconf.h>
30 #include <asm/page.h> /* for PAGE_SIZE */
31 #include <asm/div64.h>
32 #include <asm/sections.h> /* for dereference_function_descriptor() */
37 * simple_strtoull - convert a string to an unsigned long long
38 * @cp: The start of the string
39 * @endp: A pointer to the end of the parsed string will be placed here
40 * @base: The number base to use
42 unsigned long long simple_strtoull(const char *cp
, char **endp
, unsigned int base
)
44 unsigned long long result
;
47 cp
= _parse_integer_fixup_radix(cp
, &base
);
48 rv
= _parse_integer(cp
, base
, &result
);
50 cp
+= (rv
& ~KSTRTOX_OVERFLOW
);
57 EXPORT_SYMBOL(simple_strtoull
);
60 * simple_strtoul - convert a string to an unsigned long
61 * @cp: The start of the string
62 * @endp: A pointer to the end of the parsed string will be placed here
63 * @base: The number base to use
65 unsigned long simple_strtoul(const char *cp
, char **endp
, unsigned int base
)
67 return simple_strtoull(cp
, endp
, base
);
69 EXPORT_SYMBOL(simple_strtoul
);
72 * simple_strtol - convert a string to a signed long
73 * @cp: The start of the string
74 * @endp: A pointer to the end of the parsed string will be placed here
75 * @base: The number base to use
77 long simple_strtol(const char *cp
, char **endp
, unsigned int base
)
80 return -simple_strtoul(cp
+ 1, endp
, base
);
82 return simple_strtoul(cp
, endp
, base
);
84 EXPORT_SYMBOL(simple_strtol
);
87 * simple_strtoll - convert a string to a signed long long
88 * @cp: The start of the string
89 * @endp: A pointer to the end of the parsed string will be placed here
90 * @base: The number base to use
92 long long simple_strtoll(const char *cp
, char **endp
, unsigned int base
)
95 return -simple_strtoull(cp
+ 1, endp
, base
);
97 return simple_strtoull(cp
, endp
, base
);
99 EXPORT_SYMBOL(simple_strtoll
);
101 static noinline_for_stack
102 int skip_atoi(const char **s
)
107 i
= i
*10 + *((*s
)++) - '0';
112 /* Decimal conversion is by far the most typical, and is used
113 * for /proc and /sys data. This directly impacts e.g. top performance
114 * with many processes running. We optimize it for speed
116 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
117 * (with permission from the author, Douglas W. Jones). */
119 /* Formats correctly any integer in [0,99999].
120 * Outputs from one to five digits depending on input.
121 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
122 static noinline_for_stack
123 char *put_dec_trunc(char *buf
, unsigned q
)
125 unsigned d3
, d2
, d1
, d0
;
130 d0
= 6*(d3
+ d2
+ d1
) + (q
& 0xf);
131 q
= (d0
* 0xcd) >> 11;
133 *buf
++ = d0
+ '0'; /* least significant digit */
134 d1
= q
+ 9*d3
+ 5*d2
+ d1
;
136 q
= (d1
* 0xcd) >> 11;
138 *buf
++ = d1
+ '0'; /* next digit */
141 if ((d2
!= 0) || (d3
!= 0)) {
144 *buf
++ = d2
+ '0'; /* next digit */
148 q
= (d3
* 0xcd) >> 11;
150 *buf
++ = d3
+ '0'; /* next digit */
152 *buf
++ = q
+ '0'; /* most sign. digit */
159 /* Same with if's removed. Always emits five digits */
160 static noinline_for_stack
161 char *put_dec_full(char *buf
, unsigned q
)
163 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
164 /* but anyway, gcc produces better code with full-sized ints */
165 unsigned d3
, d2
, d1
, d0
;
171 * Possible ways to approx. divide by 10
172 * gcc -O2 replaces multiply with shifts and adds
173 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
174 * (x * 0x67) >> 10: 1100111
175 * (x * 0x34) >> 9: 110100 - same
176 * (x * 0x1a) >> 8: 11010 - same
177 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
179 d0
= 6*(d3
+ d2
+ d1
) + (q
& 0xf);
180 q
= (d0
* 0xcd) >> 11;
183 d1
= q
+ 9*d3
+ 5*d2
+ d1
;
184 q
= (d1
* 0xcd) >> 11;
194 q
= (d3
* 0xcd) >> 11; /* - shorter code */
195 /* q = (d3 * 0x67) >> 10; - would also work */
202 /* No inlining helps gcc to use registers better */
203 static noinline_for_stack
204 char *put_dec(char *buf
, unsigned long long num
)
209 return put_dec_trunc(buf
, num
);
210 rem
= do_div(num
, 100000);
211 buf
= put_dec_full(buf
, rem
);
215 #define ZEROPAD 1 /* pad with zero */
216 #define SIGN 2 /* unsigned/signed long */
217 #define PLUS 4 /* show plus */
218 #define SPACE 8 /* space if plus */
219 #define LEFT 16 /* left justified */
220 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
221 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
224 FORMAT_TYPE_NONE
, /* Just a string part */
226 FORMAT_TYPE_PRECISION
,
230 FORMAT_TYPE_PERCENT_CHAR
,
232 FORMAT_TYPE_LONG_LONG
,
247 u8 type
; /* format_type enum */
248 u8 flags
; /* flags to number() */
249 u8 base
; /* number base, 8, 10 or 16 only */
250 u8 qualifier
; /* number qualifier, one of 'hHlLtzZ' */
251 s16 field_width
; /* width of output field */
252 s16 precision
; /* # of digits/chars */
255 static noinline_for_stack
256 char *number(char *buf
, char *end
, unsigned long long num
,
257 struct printf_spec spec
)
259 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
260 static const char digits
[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
265 int need_pfx
= ((spec
.flags
& SPECIAL
) && spec
.base
!= 10);
268 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
269 * produces same digits or (maybe lowercased) letters */
270 locase
= (spec
.flags
& SMALL
);
271 if (spec
.flags
& LEFT
)
272 spec
.flags
&= ~ZEROPAD
;
274 if (spec
.flags
& SIGN
) {
275 if ((signed long long)num
< 0) {
277 num
= -(signed long long)num
;
279 } else if (spec
.flags
& PLUS
) {
282 } else if (spec
.flags
& SPACE
) {
293 /* generate full string in tmp[], in reverse order */
297 /* Generic code, for any base:
299 tmp[i++] = (digits[do_div(num,base)] | locase);
302 else if (spec
.base
!= 10) { /* 8 or 16 */
303 int mask
= spec
.base
- 1;
309 tmp
[i
++] = (digits
[((unsigned char)num
) & mask
] | locase
);
312 } else { /* base 10 */
313 i
= put_dec(tmp
, num
) - tmp
;
316 /* printing 100 using %2d gives "100", not "00" */
317 if (i
> spec
.precision
)
319 /* leading space padding */
320 spec
.field_width
-= spec
.precision
;
321 if (!(spec
.flags
& (ZEROPAD
+LEFT
))) {
322 while (--spec
.field_width
>= 0) {
334 /* "0x" / "0" prefix */
339 if (spec
.base
== 16) {
341 *buf
= ('X' | locase
);
345 /* zero or space padding */
346 if (!(spec
.flags
& LEFT
)) {
347 char c
= (spec
.flags
& ZEROPAD
) ? '0' : ' ';
348 while (--spec
.field_width
>= 0) {
354 /* hmm even more zero padding? */
355 while (i
<= --spec
.precision
) {
360 /* actual digits of result */
366 /* trailing space padding */
367 while (--spec
.field_width
>= 0) {
376 static noinline_for_stack
377 char *string(char *buf
, char *end
, const char *s
, struct printf_spec spec
)
381 if ((unsigned long)s
< PAGE_SIZE
)
384 len
= strnlen(s
, spec
.precision
);
386 if (!(spec
.flags
& LEFT
)) {
387 while (len
< spec
.field_width
--) {
393 for (i
= 0; i
< len
; ++i
) {
398 while (len
< spec
.field_width
--) {
407 static noinline_for_stack
408 char *symbol_string(char *buf
, char *end
, void *ptr
,
409 struct printf_spec spec
, char ext
)
411 unsigned long value
= (unsigned long) ptr
;
412 #ifdef CONFIG_KALLSYMS
413 char sym
[KSYM_SYMBOL_LEN
];
415 sprint_backtrace(sym
, value
);
416 else if (ext
!= 'f' && ext
!= 's')
417 sprint_symbol(sym
, value
);
419 kallsyms_lookup(value
, NULL
, NULL
, NULL
, sym
);
421 return string(buf
, end
, sym
, spec
);
423 spec
.field_width
= 2 * sizeof(void *);
424 spec
.flags
|= SPECIAL
| SMALL
| ZEROPAD
;
427 return number(buf
, end
, value
, spec
);
431 static noinline_for_stack
432 char *resource_string(char *buf
, char *end
, struct resource
*res
,
433 struct printf_spec spec
, const char *fmt
)
435 #ifndef IO_RSRC_PRINTK_SIZE
436 #define IO_RSRC_PRINTK_SIZE 6
439 #ifndef MEM_RSRC_PRINTK_SIZE
440 #define MEM_RSRC_PRINTK_SIZE 10
442 static const struct printf_spec io_spec
= {
444 .field_width
= IO_RSRC_PRINTK_SIZE
,
446 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
448 static const struct printf_spec mem_spec
= {
450 .field_width
= MEM_RSRC_PRINTK_SIZE
,
452 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
454 static const struct printf_spec bus_spec
= {
458 .flags
= SMALL
| ZEROPAD
,
460 static const struct printf_spec dec_spec
= {
465 static const struct printf_spec str_spec
= {
470 static const struct printf_spec flag_spec
= {
473 .flags
= SPECIAL
| SMALL
,
476 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
477 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
478 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
479 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
480 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
481 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
482 char sym
[max(2*RSRC_BUF_SIZE
+ DECODED_BUF_SIZE
,
483 2*RSRC_BUF_SIZE
+ FLAG_BUF_SIZE
+ RAW_BUF_SIZE
)];
485 char *p
= sym
, *pend
= sym
+ sizeof(sym
);
486 int decode
= (fmt
[0] == 'R') ? 1 : 0;
487 const struct printf_spec
*specp
;
490 if (res
->flags
& IORESOURCE_IO
) {
491 p
= string(p
, pend
, "io ", str_spec
);
493 } else if (res
->flags
& IORESOURCE_MEM
) {
494 p
= string(p
, pend
, "mem ", str_spec
);
496 } else if (res
->flags
& IORESOURCE_IRQ
) {
497 p
= string(p
, pend
, "irq ", str_spec
);
499 } else if (res
->flags
& IORESOURCE_DMA
) {
500 p
= string(p
, pend
, "dma ", str_spec
);
502 } else if (res
->flags
& IORESOURCE_BUS
) {
503 p
= string(p
, pend
, "bus ", str_spec
);
506 p
= string(p
, pend
, "??? ", str_spec
);
510 p
= number(p
, pend
, res
->start
, *specp
);
511 if (res
->start
!= res
->end
) {
513 p
= number(p
, pend
, res
->end
, *specp
);
516 if (res
->flags
& IORESOURCE_MEM_64
)
517 p
= string(p
, pend
, " 64bit", str_spec
);
518 if (res
->flags
& IORESOURCE_PREFETCH
)
519 p
= string(p
, pend
, " pref", str_spec
);
520 if (res
->flags
& IORESOURCE_WINDOW
)
521 p
= string(p
, pend
, " window", str_spec
);
522 if (res
->flags
& IORESOURCE_DISABLED
)
523 p
= string(p
, pend
, " disabled", str_spec
);
525 p
= string(p
, pend
, " flags ", str_spec
);
526 p
= number(p
, pend
, res
->flags
, flag_spec
);
531 return string(buf
, end
, sym
, spec
);
534 static noinline_for_stack
535 char *mac_address_string(char *buf
, char *end
, u8
*addr
,
536 struct printf_spec spec
, const char *fmt
)
538 char mac_addr
[sizeof("xx:xx:xx:xx:xx:xx")];
543 if (fmt
[1] == 'F') { /* FDDI canonical format */
549 for (i
= 0; i
< 6; i
++) {
550 p
= pack_hex_byte(p
, addr
[i
]);
551 if (fmt
[0] == 'M' && i
!= 5)
556 return string(buf
, end
, mac_addr
, spec
);
559 static noinline_for_stack
560 char *ip4_string(char *p
, const u8
*addr
, const char *fmt
)
563 bool leading_zeros
= (fmt
[0] == 'i');
588 for (i
= 0; i
< 4; i
++) {
589 char temp
[3]; /* hold each IP quad in reverse order */
590 int digits
= put_dec_trunc(temp
, addr
[index
]) - temp
;
597 /* reverse the digits in the quad */
609 static noinline_for_stack
610 char *ip6_compressed_string(char *p
, const char *addr
)
613 unsigned char zerolength
[8];
618 bool needcolon
= false;
622 memcpy(&in6
, addr
, sizeof(struct in6_addr
));
624 useIPv4
= ipv6_addr_v4mapped(&in6
) || ipv6_addr_is_isatap(&in6
);
626 memset(zerolength
, 0, sizeof(zerolength
));
633 /* find position of longest 0 run */
634 for (i
= 0; i
< range
; i
++) {
635 for (j
= i
; j
< range
; j
++) {
636 if (in6
.s6_addr16
[j
] != 0)
641 for (i
= 0; i
< range
; i
++) {
642 if (zerolength
[i
] > longest
) {
643 longest
= zerolength
[i
];
647 if (longest
== 1) /* don't compress a single 0 */
651 for (i
= 0; i
< range
; i
++) {
653 if (needcolon
|| i
== 0)
664 /* hex u16 without leading 0s */
665 word
= ntohs(in6
.s6_addr16
[i
]);
670 p
= pack_hex_byte(p
, hi
);
672 *p
++ = hex_asc_lo(hi
);
673 p
= pack_hex_byte(p
, lo
);
676 p
= pack_hex_byte(p
, lo
);
678 *p
++ = hex_asc_lo(lo
);
685 p
= ip4_string(p
, &in6
.s6_addr
[12], "I4");
692 static noinline_for_stack
693 char *ip6_string(char *p
, const char *addr
, const char *fmt
)
697 for (i
= 0; i
< 8; i
++) {
698 p
= pack_hex_byte(p
, *addr
++);
699 p
= pack_hex_byte(p
, *addr
++);
700 if (fmt
[0] == 'I' && i
!= 7)
708 static noinline_for_stack
709 char *ip6_addr_string(char *buf
, char *end
, const u8
*addr
,
710 struct printf_spec spec
, const char *fmt
)
712 char ip6_addr
[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
714 if (fmt
[0] == 'I' && fmt
[2] == 'c')
715 ip6_compressed_string(ip6_addr
, addr
);
717 ip6_string(ip6_addr
, addr
, fmt
);
719 return string(buf
, end
, ip6_addr
, spec
);
722 static noinline_for_stack
723 char *ip4_addr_string(char *buf
, char *end
, const u8
*addr
,
724 struct printf_spec spec
, const char *fmt
)
726 char ip4_addr
[sizeof("255.255.255.255")];
728 ip4_string(ip4_addr
, addr
, fmt
);
730 return string(buf
, end
, ip4_addr
, spec
);
733 static noinline_for_stack
734 char *uuid_string(char *buf
, char *end
, const u8
*addr
,
735 struct printf_spec spec
, const char *fmt
)
737 char uuid
[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
740 static const u8 be
[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
741 static const u8 le
[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
742 const u8
*index
= be
;
747 uc
= true; /* fall-through */
756 for (i
= 0; i
< 16; i
++) {
757 p
= pack_hex_byte(p
, addr
[index
[i
]]);
777 return string(buf
, end
, uuid
, spec
);
780 int kptr_restrict __read_mostly
;
783 * Show a '%p' thing. A kernel extension is that the '%p' is followed
784 * by an extra set of alphanumeric characters that are extended format
787 * Right now we handle:
789 * - 'F' For symbolic function descriptor pointers with offset
790 * - 'f' For simple symbolic function names without offset
791 * - 'S' For symbolic direct pointers with offset
792 * - 's' For symbolic direct pointers without offset
793 * - 'B' For backtraced symbolic direct pointers with offset
794 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
795 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
796 * - 'M' For a 6-byte MAC address, it prints the address in the
797 * usual colon-separated hex notation
798 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
799 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
800 * with a dash-separated hex notation
801 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
802 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
803 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
804 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
805 * IPv6 omits the colons (01020304...0f)
806 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
807 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
808 * - 'I6c' for IPv6 addresses printed as specified by
809 * http://tools.ietf.org/html/rfc5952
810 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
811 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
812 * Options for %pU are:
813 * b big endian lower case hex (default)
814 * B big endian UPPER case hex
815 * l little endian lower case hex
816 * L little endian UPPER case hex
817 * big endian output byte order is:
818 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
819 * little endian output byte order is:
820 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
821 * - 'V' For a struct va_format which contains a format string * and va_list *,
822 * call vsnprintf(->format, *->va_list).
823 * Implements a "recursive vsnprintf".
824 * Do not use this feature without some mechanism to verify the
825 * correctness of the format string and va_list arguments.
826 * - 'K' For a kernel pointer that should be hidden from unprivileged users
828 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
829 * function pointers are really function descriptors, which contain a
830 * pointer to the real address.
832 static noinline_for_stack
833 char *pointer(const char *fmt
, char *buf
, char *end
, void *ptr
,
834 struct printf_spec spec
)
836 if (!ptr
&& *fmt
!= 'K') {
838 * Print (null) with the same width as a pointer so it makes
839 * tabular output look nice.
841 if (spec
.field_width
== -1)
842 spec
.field_width
= 2 * sizeof(void *);
843 return string(buf
, end
, "(null)", spec
);
849 ptr
= dereference_function_descriptor(ptr
);
854 return symbol_string(buf
, end
, ptr
, spec
, *fmt
);
857 return resource_string(buf
, end
, ptr
, spec
, fmt
);
858 case 'M': /* Colon separated: 00:01:02:03:04:05 */
859 case 'm': /* Contiguous: 000102030405 */
860 /* [mM]F (FDDI, bit reversed) */
861 return mac_address_string(buf
, end
, ptr
, spec
, fmt
);
862 case 'I': /* Formatted IP supported
864 * 6: 0001:0203:...:0708
865 * 6c: 1::708 or 1::1.2.3.4
867 case 'i': /* Contiguous:
873 return ip6_addr_string(buf
, end
, ptr
, spec
, fmt
);
875 return ip4_addr_string(buf
, end
, ptr
, spec
, fmt
);
879 return uuid_string(buf
, end
, ptr
, spec
, fmt
);
881 return buf
+ vsnprintf(buf
, end
> buf
? end
- buf
: 0,
882 ((struct va_format
*)ptr
)->fmt
,
883 *(((struct va_format
*)ptr
)->va
));
886 * %pK cannot be used in IRQ context because its test
887 * for CAP_SYSLOG would be meaningless.
889 if (in_irq() || in_serving_softirq() || in_nmi()) {
890 if (spec
.field_width
== -1)
891 spec
.field_width
= 2 * sizeof(void *);
892 return string(buf
, end
, "pK-error", spec
);
894 if (!((kptr_restrict
== 0) ||
895 (kptr_restrict
== 1 &&
896 has_capability_noaudit(current
, CAP_SYSLOG
))))
901 if (spec
.field_width
== -1) {
902 spec
.field_width
= 2 * sizeof(void *);
903 spec
.flags
|= ZEROPAD
;
907 return number(buf
, end
, (unsigned long) ptr
, spec
);
911 * Helper function to decode printf style format.
912 * Each call decode a token from the format and return the
913 * number of characters read (or likely the delta where it wants
914 * to go on the next call).
915 * The decoded token is returned through the parameters
917 * 'h', 'l', or 'L' for integer fields
918 * 'z' support added 23/7/1999 S.H.
919 * 'z' changed to 'Z' --davidm 1/25/99
920 * 't' added for ptrdiff_t
922 * @fmt: the format string
923 * @type of the token returned
924 * @flags: various flags such as +, -, # tokens..
925 * @field_width: overwritten width
926 * @base: base of the number (octal, hex, ...)
927 * @precision: precision of a number
928 * @qualifier: qualifier of a number (long, size_t, ...)
930 static noinline_for_stack
931 int format_decode(const char *fmt
, struct printf_spec
*spec
)
933 const char *start
= fmt
;
935 /* we finished early by reading the field width */
936 if (spec
->type
== FORMAT_TYPE_WIDTH
) {
937 if (spec
->field_width
< 0) {
938 spec
->field_width
= -spec
->field_width
;
941 spec
->type
= FORMAT_TYPE_NONE
;
945 /* we finished early by reading the precision */
946 if (spec
->type
== FORMAT_TYPE_PRECISION
) {
947 if (spec
->precision
< 0)
950 spec
->type
= FORMAT_TYPE_NONE
;
955 spec
->type
= FORMAT_TYPE_NONE
;
957 for (; *fmt
; ++fmt
) {
962 /* Return the current non-format string */
963 if (fmt
!= start
|| !*fmt
)
969 while (1) { /* this also skips first '%' */
975 case '-': spec
->flags
|= LEFT
; break;
976 case '+': spec
->flags
|= PLUS
; break;
977 case ' ': spec
->flags
|= SPACE
; break;
978 case '#': spec
->flags
|= SPECIAL
; break;
979 case '0': spec
->flags
|= ZEROPAD
; break;
980 default: found
= false;
987 /* get field width */
988 spec
->field_width
= -1;
991 spec
->field_width
= skip_atoi(&fmt
);
992 else if (*fmt
== '*') {
993 /* it's the next argument */
994 spec
->type
= FORMAT_TYPE_WIDTH
;
995 return ++fmt
- start
;
999 /* get the precision */
1000 spec
->precision
= -1;
1003 if (isdigit(*fmt
)) {
1004 spec
->precision
= skip_atoi(&fmt
);
1005 if (spec
->precision
< 0)
1006 spec
->precision
= 0;
1007 } else if (*fmt
== '*') {
1008 /* it's the next argument */
1009 spec
->type
= FORMAT_TYPE_PRECISION
;
1010 return ++fmt
- start
;
1015 /* get the conversion qualifier */
1016 spec
->qualifier
= -1;
1017 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
1018 _tolower(*fmt
) == 'z' || *fmt
== 't') {
1019 spec
->qualifier
= *fmt
++;
1020 if (unlikely(spec
->qualifier
== *fmt
)) {
1021 if (spec
->qualifier
== 'l') {
1022 spec
->qualifier
= 'L';
1024 } else if (spec
->qualifier
== 'h') {
1025 spec
->qualifier
= 'H';
1035 spec
->type
= FORMAT_TYPE_CHAR
;
1036 return ++fmt
- start
;
1039 spec
->type
= FORMAT_TYPE_STR
;
1040 return ++fmt
- start
;
1043 spec
->type
= FORMAT_TYPE_PTR
;
1048 spec
->type
= FORMAT_TYPE_NRCHARS
;
1049 return ++fmt
- start
;
1052 spec
->type
= FORMAT_TYPE_PERCENT_CHAR
;
1053 return ++fmt
- start
;
1055 /* integer number formats - set up the flags and "break" */
1061 spec
->flags
|= SMALL
;
1069 spec
->flags
|= SIGN
;
1074 spec
->type
= FORMAT_TYPE_INVALID
;
1078 if (spec
->qualifier
== 'L')
1079 spec
->type
= FORMAT_TYPE_LONG_LONG
;
1080 else if (spec
->qualifier
== 'l') {
1081 if (spec
->flags
& SIGN
)
1082 spec
->type
= FORMAT_TYPE_LONG
;
1084 spec
->type
= FORMAT_TYPE_ULONG
;
1085 } else if (_tolower(spec
->qualifier
) == 'z') {
1086 spec
->type
= FORMAT_TYPE_SIZE_T
;
1087 } else if (spec
->qualifier
== 't') {
1088 spec
->type
= FORMAT_TYPE_PTRDIFF
;
1089 } else if (spec
->qualifier
== 'H') {
1090 if (spec
->flags
& SIGN
)
1091 spec
->type
= FORMAT_TYPE_BYTE
;
1093 spec
->type
= FORMAT_TYPE_UBYTE
;
1094 } else if (spec
->qualifier
== 'h') {
1095 if (spec
->flags
& SIGN
)
1096 spec
->type
= FORMAT_TYPE_SHORT
;
1098 spec
->type
= FORMAT_TYPE_USHORT
;
1100 if (spec
->flags
& SIGN
)
1101 spec
->type
= FORMAT_TYPE_INT
;
1103 spec
->type
= FORMAT_TYPE_UINT
;
1106 return ++fmt
- start
;
1110 * vsnprintf - Format a string and place it in a buffer
1111 * @buf: The buffer to place the result into
1112 * @size: The size of the buffer, including the trailing null space
1113 * @fmt: The format string to use
1114 * @args: Arguments for the format string
1116 * This function follows C99 vsnprintf, but has some extensions:
1117 * %pS output the name of a text symbol with offset
1118 * %ps output the name of a text symbol without offset
1119 * %pF output the name of a function pointer with its offset
1120 * %pf output the name of a function pointer without its offset
1121 * %pB output the name of a backtrace symbol with its offset
1122 * %pR output the address range in a struct resource with decoded flags
1123 * %pr output the address range in a struct resource with raw flags
1124 * %pM output a 6-byte MAC address with colons
1125 * %pm output a 6-byte MAC address without colons
1126 * %pI4 print an IPv4 address without leading zeros
1127 * %pi4 print an IPv4 address with leading zeros
1128 * %pI6 print an IPv6 address with colons
1129 * %pi6 print an IPv6 address without colons
1130 * %pI6c print an IPv6 address as specified by RFC 5952
1131 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1135 * The return value is the number of characters which would
1136 * be generated for the given input, excluding the trailing
1137 * '\0', as per ISO C99. If you want to have the exact
1138 * number of characters written into @buf as return value
1139 * (not including the trailing '\0'), use vscnprintf(). If the
1140 * return is greater than or equal to @size, the resulting
1141 * string is truncated.
1143 * If you're not already dealing with a va_list consider using snprintf().
1145 int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1147 unsigned long long num
;
1149 struct printf_spec spec
= {0};
1151 /* Reject out-of-range values early. Large positive sizes are
1152 used for unknown buffer sizes. */
1153 if (WARN_ON_ONCE((int) size
< 0))
1159 /* Make sure end is always >= buf */
1166 const char *old_fmt
= fmt
;
1167 int read
= format_decode(fmt
, &spec
);
1171 switch (spec
.type
) {
1172 case FORMAT_TYPE_NONE
: {
1175 if (copy
> end
- str
)
1177 memcpy(str
, old_fmt
, copy
);
1183 case FORMAT_TYPE_WIDTH
:
1184 spec
.field_width
= va_arg(args
, int);
1187 case FORMAT_TYPE_PRECISION
:
1188 spec
.precision
= va_arg(args
, int);
1191 case FORMAT_TYPE_CHAR
: {
1194 if (!(spec
.flags
& LEFT
)) {
1195 while (--spec
.field_width
> 0) {
1202 c
= (unsigned char) va_arg(args
, int);
1206 while (--spec
.field_width
> 0) {
1214 case FORMAT_TYPE_STR
:
1215 str
= string(str
, end
, va_arg(args
, char *), spec
);
1218 case FORMAT_TYPE_PTR
:
1219 str
= pointer(fmt
+1, str
, end
, va_arg(args
, void *),
1221 while (isalnum(*fmt
))
1225 case FORMAT_TYPE_PERCENT_CHAR
:
1231 case FORMAT_TYPE_INVALID
:
1237 case FORMAT_TYPE_NRCHARS
: {
1238 u8 qualifier
= spec
.qualifier
;
1240 if (qualifier
== 'l') {
1241 long *ip
= va_arg(args
, long *);
1243 } else if (_tolower(qualifier
) == 'z') {
1244 size_t *ip
= va_arg(args
, size_t *);
1247 int *ip
= va_arg(args
, int *);
1254 switch (spec
.type
) {
1255 case FORMAT_TYPE_LONG_LONG
:
1256 num
= va_arg(args
, long long);
1258 case FORMAT_TYPE_ULONG
:
1259 num
= va_arg(args
, unsigned long);
1261 case FORMAT_TYPE_LONG
:
1262 num
= va_arg(args
, long);
1264 case FORMAT_TYPE_SIZE_T
:
1265 num
= va_arg(args
, size_t);
1267 case FORMAT_TYPE_PTRDIFF
:
1268 num
= va_arg(args
, ptrdiff_t);
1270 case FORMAT_TYPE_UBYTE
:
1271 num
= (unsigned char) va_arg(args
, int);
1273 case FORMAT_TYPE_BYTE
:
1274 num
= (signed char) va_arg(args
, int);
1276 case FORMAT_TYPE_USHORT
:
1277 num
= (unsigned short) va_arg(args
, int);
1279 case FORMAT_TYPE_SHORT
:
1280 num
= (short) va_arg(args
, int);
1282 case FORMAT_TYPE_INT
:
1283 num
= (int) va_arg(args
, int);
1286 num
= va_arg(args
, unsigned int);
1289 str
= number(str
, end
, num
, spec
);
1300 /* the trailing null byte doesn't count towards the total */
1304 EXPORT_SYMBOL(vsnprintf
);
1307 * vscnprintf - Format a string and place it in a buffer
1308 * @buf: The buffer to place the result into
1309 * @size: The size of the buffer, including the trailing null space
1310 * @fmt: The format string to use
1311 * @args: Arguments for the format string
1313 * The return value is the number of characters which have been written into
1314 * the @buf not including the trailing '\0'. If @size is == 0 the function
1317 * If you're not already dealing with a va_list consider using scnprintf().
1319 * See the vsnprintf() documentation for format string extensions over C99.
1321 int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
1325 i
= vsnprintf(buf
, size
, fmt
, args
);
1327 if (likely(i
< size
))
1333 EXPORT_SYMBOL(vscnprintf
);
1336 * snprintf - Format a string and place it in a buffer
1337 * @buf: The buffer to place the result into
1338 * @size: The size of the buffer, including the trailing null space
1339 * @fmt: The format string to use
1340 * @...: Arguments for the format string
1342 * The return value is the number of characters which would be
1343 * generated for the given input, excluding the trailing null,
1344 * as per ISO C99. If the return is greater than or equal to
1345 * @size, the resulting string is truncated.
1347 * See the vsnprintf() documentation for format string extensions over C99.
1349 int snprintf(char *buf
, size_t size
, const char *fmt
, ...)
1354 va_start(args
, fmt
);
1355 i
= vsnprintf(buf
, size
, fmt
, args
);
1360 EXPORT_SYMBOL(snprintf
);
1363 * scnprintf - Format a string and place it in a buffer
1364 * @buf: The buffer to place the result into
1365 * @size: The size of the buffer, including the trailing null space
1366 * @fmt: The format string to use
1367 * @...: Arguments for the format string
1369 * The return value is the number of characters written into @buf not including
1370 * the trailing '\0'. If @size is == 0 the function returns 0.
1373 int scnprintf(char *buf
, size_t size
, const char *fmt
, ...)
1378 va_start(args
, fmt
);
1379 i
= vscnprintf(buf
, size
, fmt
, args
);
1384 EXPORT_SYMBOL(scnprintf
);
1387 * vsprintf - Format a string and place it in a buffer
1388 * @buf: The buffer to place the result into
1389 * @fmt: The format string to use
1390 * @args: Arguments for the format string
1392 * The function returns the number of characters written
1393 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1396 * If you're not already dealing with a va_list consider using sprintf().
1398 * See the vsnprintf() documentation for format string extensions over C99.
1400 int vsprintf(char *buf
, const char *fmt
, va_list args
)
1402 return vsnprintf(buf
, INT_MAX
, fmt
, args
);
1404 EXPORT_SYMBOL(vsprintf
);
1407 * sprintf - Format a string and place it in a buffer
1408 * @buf: The buffer to place the result into
1409 * @fmt: The format string to use
1410 * @...: Arguments for the format string
1412 * The function returns the number of characters written
1413 * into @buf. Use snprintf() or scnprintf() in order to avoid
1416 * See the vsnprintf() documentation for format string extensions over C99.
1418 int sprintf(char *buf
, const char *fmt
, ...)
1423 va_start(args
, fmt
);
1424 i
= vsnprintf(buf
, INT_MAX
, fmt
, args
);
1429 EXPORT_SYMBOL(sprintf
);
1431 #ifdef CONFIG_BINARY_PRINTF
1434 * vbin_printf() - VA arguments to binary data
1435 * bstr_printf() - Binary data to text string
1439 * vbin_printf - Parse a format string and place args' binary value in a buffer
1440 * @bin_buf: The buffer to place args' binary value
1441 * @size: The size of the buffer(by words(32bits), not characters)
1442 * @fmt: The format string to use
1443 * @args: Arguments for the format string
1445 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1448 * The return value is the number of words(32bits) which would be generated for
1452 * If the return value is greater than @size, the resulting bin_buf is NOT
1453 * valid for bstr_printf().
1455 int vbin_printf(u32
*bin_buf
, size_t size
, const char *fmt
, va_list args
)
1457 struct printf_spec spec
= {0};
1460 str
= (char *)bin_buf
;
1461 end
= (char *)(bin_buf
+ size
);
1463 #define save_arg(type) \
1465 if (sizeof(type) == 8) { \
1466 unsigned long long value; \
1467 str = PTR_ALIGN(str, sizeof(u32)); \
1468 value = va_arg(args, unsigned long long); \
1469 if (str + sizeof(type) <= end) { \
1470 *(u32 *)str = *(u32 *)&value; \
1471 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1474 unsigned long value; \
1475 str = PTR_ALIGN(str, sizeof(type)); \
1476 value = va_arg(args, int); \
1477 if (str + sizeof(type) <= end) \
1478 *(typeof(type) *)str = (type)value; \
1480 str += sizeof(type); \
1484 int read
= format_decode(fmt
, &spec
);
1488 switch (spec
.type
) {
1489 case FORMAT_TYPE_NONE
:
1490 case FORMAT_TYPE_INVALID
:
1491 case FORMAT_TYPE_PERCENT_CHAR
:
1494 case FORMAT_TYPE_WIDTH
:
1495 case FORMAT_TYPE_PRECISION
:
1499 case FORMAT_TYPE_CHAR
:
1503 case FORMAT_TYPE_STR
: {
1504 const char *save_str
= va_arg(args
, char *);
1507 if ((unsigned long)save_str
> (unsigned long)-PAGE_SIZE
1508 || (unsigned long)save_str
< PAGE_SIZE
)
1509 save_str
= "(null)";
1510 len
= strlen(save_str
) + 1;
1511 if (str
+ len
< end
)
1512 memcpy(str
, save_str
, len
);
1517 case FORMAT_TYPE_PTR
:
1519 /* skip all alphanumeric pointer suffixes */
1520 while (isalnum(*fmt
))
1524 case FORMAT_TYPE_NRCHARS
: {
1525 /* skip %n 's argument */
1526 u8 qualifier
= spec
.qualifier
;
1528 if (qualifier
== 'l')
1529 skip_arg
= va_arg(args
, long *);
1530 else if (_tolower(qualifier
) == 'z')
1531 skip_arg
= va_arg(args
, size_t *);
1533 skip_arg
= va_arg(args
, int *);
1538 switch (spec
.type
) {
1540 case FORMAT_TYPE_LONG_LONG
:
1541 save_arg(long long);
1543 case FORMAT_TYPE_ULONG
:
1544 case FORMAT_TYPE_LONG
:
1545 save_arg(unsigned long);
1547 case FORMAT_TYPE_SIZE_T
:
1550 case FORMAT_TYPE_PTRDIFF
:
1551 save_arg(ptrdiff_t);
1553 case FORMAT_TYPE_UBYTE
:
1554 case FORMAT_TYPE_BYTE
:
1557 case FORMAT_TYPE_USHORT
:
1558 case FORMAT_TYPE_SHORT
:
1567 return (u32
*)(PTR_ALIGN(str
, sizeof(u32
))) - bin_buf
;
1570 EXPORT_SYMBOL_GPL(vbin_printf
);
1573 * bstr_printf - Format a string from binary arguments and place it in a buffer
1574 * @buf: The buffer to place the result into
1575 * @size: The size of the buffer, including the trailing null space
1576 * @fmt: The format string to use
1577 * @bin_buf: Binary arguments for the format string
1579 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1580 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1581 * a binary buffer that generated by vbin_printf.
1583 * The format follows C99 vsnprintf, but has some extensions:
1584 * see vsnprintf comment for details.
1586 * The return value is the number of characters which would
1587 * be generated for the given input, excluding the trailing
1588 * '\0', as per ISO C99. If you want to have the exact
1589 * number of characters written into @buf as return value
1590 * (not including the trailing '\0'), use vscnprintf(). If the
1591 * return is greater than or equal to @size, the resulting
1592 * string is truncated.
1594 int bstr_printf(char *buf
, size_t size
, const char *fmt
, const u32
*bin_buf
)
1596 struct printf_spec spec
= {0};
1598 const char *args
= (const char *)bin_buf
;
1600 if (WARN_ON_ONCE((int) size
< 0))
1606 #define get_arg(type) \
1608 typeof(type) value; \
1609 if (sizeof(type) == 8) { \
1610 args = PTR_ALIGN(args, sizeof(u32)); \
1611 *(u32 *)&value = *(u32 *)args; \
1612 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1614 args = PTR_ALIGN(args, sizeof(type)); \
1615 value = *(typeof(type) *)args; \
1617 args += sizeof(type); \
1621 /* Make sure end is always >= buf */
1628 const char *old_fmt
= fmt
;
1629 int read
= format_decode(fmt
, &spec
);
1633 switch (spec
.type
) {
1634 case FORMAT_TYPE_NONE
: {
1637 if (copy
> end
- str
)
1639 memcpy(str
, old_fmt
, copy
);
1645 case FORMAT_TYPE_WIDTH
:
1646 spec
.field_width
= get_arg(int);
1649 case FORMAT_TYPE_PRECISION
:
1650 spec
.precision
= get_arg(int);
1653 case FORMAT_TYPE_CHAR
: {
1656 if (!(spec
.flags
& LEFT
)) {
1657 while (--spec
.field_width
> 0) {
1663 c
= (unsigned char) get_arg(char);
1667 while (--spec
.field_width
> 0) {
1675 case FORMAT_TYPE_STR
: {
1676 const char *str_arg
= args
;
1677 args
+= strlen(str_arg
) + 1;
1678 str
= string(str
, end
, (char *)str_arg
, spec
);
1682 case FORMAT_TYPE_PTR
:
1683 str
= pointer(fmt
+1, str
, end
, get_arg(void *), spec
);
1684 while (isalnum(*fmt
))
1688 case FORMAT_TYPE_PERCENT_CHAR
:
1689 case FORMAT_TYPE_INVALID
:
1695 case FORMAT_TYPE_NRCHARS
:
1700 unsigned long long num
;
1702 switch (spec
.type
) {
1704 case FORMAT_TYPE_LONG_LONG
:
1705 num
= get_arg(long long);
1707 case FORMAT_TYPE_ULONG
:
1708 case FORMAT_TYPE_LONG
:
1709 num
= get_arg(unsigned long);
1711 case FORMAT_TYPE_SIZE_T
:
1712 num
= get_arg(size_t);
1714 case FORMAT_TYPE_PTRDIFF
:
1715 num
= get_arg(ptrdiff_t);
1717 case FORMAT_TYPE_UBYTE
:
1718 num
= get_arg(unsigned char);
1720 case FORMAT_TYPE_BYTE
:
1721 num
= get_arg(signed char);
1723 case FORMAT_TYPE_USHORT
:
1724 num
= get_arg(unsigned short);
1726 case FORMAT_TYPE_SHORT
:
1727 num
= get_arg(short);
1729 case FORMAT_TYPE_UINT
:
1730 num
= get_arg(unsigned int);
1736 str
= number(str
, end
, num
, spec
);
1738 } /* switch(spec.type) */
1750 /* the trailing null byte doesn't count towards the total */
1753 EXPORT_SYMBOL_GPL(bstr_printf
);
1756 * bprintf - Parse a format string and place args' binary value in a buffer
1757 * @bin_buf: The buffer to place args' binary value
1758 * @size: The size of the buffer(by words(32bits), not characters)
1759 * @fmt: The format string to use
1760 * @...: Arguments for the format string
1762 * The function returns the number of words(u32) written
1765 int bprintf(u32
*bin_buf
, size_t size
, const char *fmt
, ...)
1770 va_start(args
, fmt
);
1771 ret
= vbin_printf(bin_buf
, size
, fmt
, args
);
1776 EXPORT_SYMBOL_GPL(bprintf
);
1778 #endif /* CONFIG_BINARY_PRINTF */
1781 * vsscanf - Unformat a buffer into a list of arguments
1782 * @buf: input buffer
1783 * @fmt: format of buffer
1786 int vsscanf(const char *buf
, const char *fmt
, va_list args
)
1788 const char *str
= buf
;
1797 while (*fmt
&& *str
) {
1798 /* skip any white space in format */
1799 /* white space in format matchs any amount of
1800 * white space, including none, in the input.
1802 if (isspace(*fmt
)) {
1803 fmt
= skip_spaces(++fmt
);
1804 str
= skip_spaces(str
);
1807 /* anything that is not a conversion must match exactly */
1808 if (*fmt
!= '%' && *fmt
) {
1809 if (*fmt
++ != *str
++)
1818 /* skip this conversion.
1819 * advance both strings to next white space
1822 while (!isspace(*fmt
) && *fmt
!= '%' && *fmt
)
1824 while (!isspace(*str
) && *str
)
1829 /* get field width */
1832 field_width
= skip_atoi(&fmt
);
1834 /* get conversion qualifier */
1836 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
1837 _tolower(*fmt
) == 'z') {
1839 if (unlikely(qualifier
== *fmt
)) {
1840 if (qualifier
== 'h') {
1843 } else if (qualifier
== 'l') {
1859 char *s
= (char *)va_arg(args
, char*);
1860 if (field_width
== -1)
1864 } while (--field_width
> 0 && *str
);
1870 char *s
= (char *)va_arg(args
, char *);
1871 if (field_width
== -1)
1872 field_width
= SHRT_MAX
;
1873 /* first, skip leading white space in buffer */
1874 str
= skip_spaces(str
);
1876 /* now copy until next white space */
1877 while (*str
&& !isspace(*str
) && field_width
--)
1884 /* return number of characters read so far */
1886 int *i
= (int *)va_arg(args
, int*);
1904 /* looking for '%' in str */
1909 /* invalid format; stop here */
1913 /* have some sort of integer conversion.
1914 * first, skip white space in buffer.
1916 str
= skip_spaces(str
);
1919 if (is_sign
&& digit
== '-')
1923 || (base
== 16 && !isxdigit(digit
))
1924 || (base
== 10 && !isdigit(digit
))
1925 || (base
== 8 && (!isdigit(digit
) || digit
> '7'))
1926 || (base
== 0 && !isdigit(digit
)))
1929 switch (qualifier
) {
1930 case 'H': /* that's 'hh' in format */
1932 signed char *s
= (signed char *)va_arg(args
, signed char *);
1933 *s
= (signed char)simple_strtol(str
, &next
, base
);
1935 unsigned char *s
= (unsigned char *)va_arg(args
, unsigned char *);
1936 *s
= (unsigned char)simple_strtoul(str
, &next
, base
);
1941 short *s
= (short *)va_arg(args
, short *);
1942 *s
= (short)simple_strtol(str
, &next
, base
);
1944 unsigned short *s
= (unsigned short *)va_arg(args
, unsigned short *);
1945 *s
= (unsigned short)simple_strtoul(str
, &next
, base
);
1950 long *l
= (long *)va_arg(args
, long *);
1951 *l
= simple_strtol(str
, &next
, base
);
1953 unsigned long *l
= (unsigned long *)va_arg(args
, unsigned long *);
1954 *l
= simple_strtoul(str
, &next
, base
);
1959 long long *l
= (long long *)va_arg(args
, long long *);
1960 *l
= simple_strtoll(str
, &next
, base
);
1962 unsigned long long *l
= (unsigned long long *)va_arg(args
, unsigned long long *);
1963 *l
= simple_strtoull(str
, &next
, base
);
1969 size_t *s
= (size_t *)va_arg(args
, size_t *);
1970 *s
= (size_t)simple_strtoul(str
, &next
, base
);
1975 int *i
= (int *)va_arg(args
, int *);
1976 *i
= (int)simple_strtol(str
, &next
, base
);
1978 unsigned int *i
= (unsigned int *)va_arg(args
, unsigned int*);
1979 *i
= (unsigned int)simple_strtoul(str
, &next
, base
);
1991 * Now we've come all the way through so either the input string or the
1992 * format ended. In the former case, there can be a %n at the current
1993 * position in the format that needs to be filled.
1995 if (*fmt
== '%' && *(fmt
+ 1) == 'n') {
1996 int *p
= (int *)va_arg(args
, int *);
2002 EXPORT_SYMBOL(vsscanf
);
2005 * sscanf - Unformat a buffer into a list of arguments
2006 * @buf: input buffer
2007 * @fmt: formatting of buffer
2008 * @...: resulting arguments
2010 int sscanf(const char *buf
, const char *fmt
, ...)
2015 va_start(args
, fmt
);
2016 i
= vsscanf(buf
, fmt
, args
);
2021 EXPORT_SYMBOL(sscanf
);