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 = hex_byte_pack(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 = hex_byte_pack(p, hi);
672 *p++ = hex_asc_lo(hi);
673 p = hex_byte_pack(p, lo);
676 p = hex_byte_pack(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 = hex_byte_pack(p, *addr++);
699 p = hex_byte_pack(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 = hex_byte_pack(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 (kptr_restrict && (in_irq() || in_serving_softirq() ||
891 if (spec.field_width == -1)
892 spec.field_width = 2 * sizeof(void *);
893 return string(buf, end, "pK-error", spec);
895 if (!((kptr_restrict == 0) ||
896 (kptr_restrict == 1 &&
897 has_capability_noaudit(current, CAP_SYSLOG))))
902 if (spec.field_width == -1) {
903 spec.field_width = 2 * sizeof(void *);
904 spec.flags |= ZEROPAD;
908 return number(buf, end, (unsigned long) ptr, spec);
912 * Helper function to decode printf style format.
913 * Each call decode a token from the format and return the
914 * number of characters read (or likely the delta where it wants
915 * to go on the next call).
916 * The decoded token is returned through the parameters
918 * 'h', 'l', or 'L' for integer fields
919 * 'z' support added 23/7/1999 S.H.
920 * 'z' changed to 'Z' --davidm 1/25/99
921 * 't' added for ptrdiff_t
923 * @fmt: the format string
924 * @type of the token returned
925 * @flags: various flags such as +, -, # tokens..
926 * @field_width: overwritten width
927 * @base: base of the number (octal, hex, ...)
928 * @precision: precision of a number
929 * @qualifier: qualifier of a number (long, size_t, ...)
931 static noinline_for_stack
932 int format_decode(const char *fmt, struct printf_spec *spec)
934 const char *start = fmt;
936 /* we finished early by reading the field width */
937 if (spec->type == FORMAT_TYPE_WIDTH) {
938 if (spec->field_width < 0) {
939 spec->field_width = -spec->field_width;
942 spec->type = FORMAT_TYPE_NONE;
946 /* we finished early by reading the precision */
947 if (spec->type == FORMAT_TYPE_PRECISION) {
948 if (spec->precision < 0)
951 spec->type = FORMAT_TYPE_NONE;
956 spec->type = FORMAT_TYPE_NONE;
958 for (; *fmt ; ++fmt) {
963 /* Return the current non-format string */
964 if (fmt != start || !*fmt)
970 while (1) { /* this also skips first '%' */
976 case '-': spec->flags |= LEFT; break;
977 case '+': spec->flags |= PLUS; break;
978 case ' ': spec->flags |= SPACE; break;
979 case '#': spec->flags |= SPECIAL; break;
980 case '0': spec->flags |= ZEROPAD; break;
981 default: found = false;
988 /* get field width */
989 spec->field_width = -1;
992 spec->field_width = skip_atoi(&fmt);
993 else if (*fmt == '*') {
994 /* it's the next argument */
995 spec->type = FORMAT_TYPE_WIDTH;
996 return ++fmt - start;
1000 /* get the precision */
1001 spec->precision = -1;
1004 if (isdigit(*fmt)) {
1005 spec->precision = skip_atoi(&fmt);
1006 if (spec->precision < 0)
1007 spec->precision = 0;
1008 } else if (*fmt == '*') {
1009 /* it's the next argument */
1010 spec->type = FORMAT_TYPE_PRECISION;
1011 return ++fmt - start;
1016 /* get the conversion qualifier */
1017 spec->qualifier = -1;
1018 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1019 _tolower(*fmt) == 'z' || *fmt == 't') {
1020 spec->qualifier = *fmt++;
1021 if (unlikely(spec->qualifier == *fmt)) {
1022 if (spec->qualifier == 'l') {
1023 spec->qualifier = 'L';
1025 } else if (spec->qualifier == 'h') {
1026 spec->qualifier = 'H';
1036 spec->type = FORMAT_TYPE_CHAR;
1037 return ++fmt - start;
1040 spec->type = FORMAT_TYPE_STR;
1041 return ++fmt - start;
1044 spec->type = FORMAT_TYPE_PTR;
1049 spec->type = FORMAT_TYPE_NRCHARS;
1050 return ++fmt - start;
1053 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1054 return ++fmt - start;
1056 /* integer number formats - set up the flags and "break" */
1062 spec->flags |= SMALL;
1070 spec->flags |= SIGN;
1075 spec->type = FORMAT_TYPE_INVALID;
1079 if (spec->qualifier == 'L')
1080 spec->type = FORMAT_TYPE_LONG_LONG;
1081 else if (spec->qualifier == 'l') {
1082 if (spec->flags & SIGN)
1083 spec->type = FORMAT_TYPE_LONG;
1085 spec->type = FORMAT_TYPE_ULONG;
1086 } else if (_tolower(spec->qualifier) == 'z') {
1087 spec->type = FORMAT_TYPE_SIZE_T;
1088 } else if (spec->qualifier == 't') {
1089 spec->type = FORMAT_TYPE_PTRDIFF;
1090 } else if (spec->qualifier == 'H') {
1091 if (spec->flags & SIGN)
1092 spec->type = FORMAT_TYPE_BYTE;
1094 spec->type = FORMAT_TYPE_UBYTE;
1095 } else if (spec->qualifier == 'h') {
1096 if (spec->flags & SIGN)
1097 spec->type = FORMAT_TYPE_SHORT;
1099 spec->type = FORMAT_TYPE_USHORT;
1101 if (spec->flags & SIGN)
1102 spec->type = FORMAT_TYPE_INT;
1104 spec->type = FORMAT_TYPE_UINT;
1107 return ++fmt - start;
1111 * vsnprintf - Format a string and place it in a buffer
1112 * @buf: The buffer to place the result into
1113 * @size: The size of the buffer, including the trailing null space
1114 * @fmt: The format string to use
1115 * @args: Arguments for the format string
1117 * This function follows C99 vsnprintf, but has some extensions:
1118 * %pS output the name of a text symbol with offset
1119 * %ps output the name of a text symbol without offset
1120 * %pF output the name of a function pointer with its offset
1121 * %pf output the name of a function pointer without its offset
1122 * %pB output the name of a backtrace symbol with its offset
1123 * %pR output the address range in a struct resource with decoded flags
1124 * %pr output the address range in a struct resource with raw flags
1125 * %pM output a 6-byte MAC address with colons
1126 * %pm output a 6-byte MAC address without colons
1127 * %pI4 print an IPv4 address without leading zeros
1128 * %pi4 print an IPv4 address with leading zeros
1129 * %pI6 print an IPv6 address with colons
1130 * %pi6 print an IPv6 address without colons
1131 * %pI6c print an IPv6 address as specified by RFC 5952
1132 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1136 * The return value is the number of characters which would
1137 * be generated for the given input, excluding the trailing
1138 * '\0', as per ISO C99. If you want to have the exact
1139 * number of characters written into @buf as return value
1140 * (not including the trailing '\0'), use vscnprintf(). If the
1141 * return is greater than or equal to @size, the resulting
1142 * string is truncated.
1144 * If you're not already dealing with a va_list consider using snprintf().
1146 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1148 unsigned long long num;
1150 struct printf_spec spec = {0};
1152 /* Reject out-of-range values early. Large positive sizes are
1153 used for unknown buffer sizes. */
1154 if (WARN_ON_ONCE((int) size < 0))
1160 /* Make sure end is always >= buf */
1167 const char *old_fmt = fmt;
1168 int read = format_decode(fmt, &spec);
1172 switch (spec.type) {
1173 case FORMAT_TYPE_NONE: {
1176 if (copy > end - str)
1178 memcpy(str, old_fmt, copy);
1184 case FORMAT_TYPE_WIDTH:
1185 spec.field_width = va_arg(args, int);
1188 case FORMAT_TYPE_PRECISION:
1189 spec.precision = va_arg(args, int);
1192 case FORMAT_TYPE_CHAR: {
1195 if (!(spec.flags & LEFT)) {
1196 while (--spec.field_width > 0) {
1203 c = (unsigned char) va_arg(args, int);
1207 while (--spec.field_width > 0) {
1215 case FORMAT_TYPE_STR:
1216 str = string(str, end, va_arg(args, char *), spec);
1219 case FORMAT_TYPE_PTR:
1220 str = pointer(fmt+1, str, end, va_arg(args, void *),
1222 while (isalnum(*fmt))
1226 case FORMAT_TYPE_PERCENT_CHAR:
1232 case FORMAT_TYPE_INVALID:
1238 case FORMAT_TYPE_NRCHARS: {
1239 u8 qualifier = spec.qualifier;
1241 if (qualifier == 'l') {
1242 long *ip = va_arg(args, long *);
1244 } else if (_tolower(qualifier) == 'z') {
1245 size_t *ip = va_arg(args, size_t *);
1248 int *ip = va_arg(args, int *);
1255 switch (spec.type) {
1256 case FORMAT_TYPE_LONG_LONG:
1257 num = va_arg(args, long long);
1259 case FORMAT_TYPE_ULONG:
1260 num = va_arg(args, unsigned long);
1262 case FORMAT_TYPE_LONG:
1263 num = va_arg(args, long);
1265 case FORMAT_TYPE_SIZE_T:
1266 num = va_arg(args, size_t);
1268 case FORMAT_TYPE_PTRDIFF:
1269 num = va_arg(args, ptrdiff_t);
1271 case FORMAT_TYPE_UBYTE:
1272 num = (unsigned char) va_arg(args, int);
1274 case FORMAT_TYPE_BYTE:
1275 num = (signed char) va_arg(args, int);
1277 case FORMAT_TYPE_USHORT:
1278 num = (unsigned short) va_arg(args, int);
1280 case FORMAT_TYPE_SHORT:
1281 num = (short) va_arg(args, int);
1283 case FORMAT_TYPE_INT:
1284 num = (int) va_arg(args, int);
1287 num = va_arg(args, unsigned int);
1290 str = number(str, end, num, spec);
1301 /* the trailing null byte doesn't count towards the total */
1305 EXPORT_SYMBOL(vsnprintf);
1308 * vscnprintf - Format a string and place it in a buffer
1309 * @buf: The buffer to place the result into
1310 * @size: The size of the buffer, including the trailing null space
1311 * @fmt: The format string to use
1312 * @args: Arguments for the format string
1314 * The return value is the number of characters which have been written into
1315 * the @buf not including the trailing '\0'. If @size is == 0 the function
1318 * If you're not already dealing with a va_list consider using scnprintf().
1320 * See the vsnprintf() documentation for format string extensions over C99.
1322 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1326 i = vsnprintf(buf, size, fmt, args);
1328 if (likely(i < size))
1334 EXPORT_SYMBOL(vscnprintf);
1337 * snprintf - Format a string and place it in a buffer
1338 * @buf: The buffer to place the result into
1339 * @size: The size of the buffer, including the trailing null space
1340 * @fmt: The format string to use
1341 * @...: Arguments for the format string
1343 * The return value is the number of characters which would be
1344 * generated for the given input, excluding the trailing null,
1345 * as per ISO C99. If the return is greater than or equal to
1346 * @size, the resulting string is truncated.
1348 * See the vsnprintf() documentation for format string extensions over C99.
1350 int snprintf(char *buf, size_t size, const char *fmt, ...)
1355 va_start(args, fmt);
1356 i = vsnprintf(buf, size, fmt, args);
1361 EXPORT_SYMBOL(snprintf);
1364 * scnprintf - Format a string and place it in a buffer
1365 * @buf: The buffer to place the result into
1366 * @size: The size of the buffer, including the trailing null space
1367 * @fmt: The format string to use
1368 * @...: Arguments for the format string
1370 * The return value is the number of characters written into @buf not including
1371 * the trailing '\0'. If @size is == 0 the function returns 0.
1374 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1379 va_start(args, fmt);
1380 i = vscnprintf(buf, size, fmt, args);
1385 EXPORT_SYMBOL(scnprintf);
1388 * vsprintf - Format a string and place it in a buffer
1389 * @buf: The buffer to place the result into
1390 * @fmt: The format string to use
1391 * @args: Arguments for the format string
1393 * The function returns the number of characters written
1394 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1397 * If you're not already dealing with a va_list consider using sprintf().
1399 * See the vsnprintf() documentation for format string extensions over C99.
1401 int vsprintf(char *buf, const char *fmt, va_list args)
1403 return vsnprintf(buf, INT_MAX, fmt, args);
1405 EXPORT_SYMBOL(vsprintf);
1408 * sprintf - Format a string and place it in a buffer
1409 * @buf: The buffer to place the result into
1410 * @fmt: The format string to use
1411 * @...: Arguments for the format string
1413 * The function returns the number of characters written
1414 * into @buf. Use snprintf() or scnprintf() in order to avoid
1417 * See the vsnprintf() documentation for format string extensions over C99.
1419 int sprintf(char *buf, const char *fmt, ...)
1424 va_start(args, fmt);
1425 i = vsnprintf(buf, INT_MAX, fmt, args);
1430 EXPORT_SYMBOL(sprintf);
1432 #ifdef CONFIG_BINARY_PRINTF
1435 * vbin_printf() - VA arguments to binary data
1436 * bstr_printf() - Binary data to text string
1440 * vbin_printf - Parse a format string and place args' binary value in a buffer
1441 * @bin_buf: The buffer to place args' binary value
1442 * @size: The size of the buffer(by words(32bits), not characters)
1443 * @fmt: The format string to use
1444 * @args: Arguments for the format string
1446 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1449 * The return value is the number of words(32bits) which would be generated for
1453 * If the return value is greater than @size, the resulting bin_buf is NOT
1454 * valid for bstr_printf().
1456 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1458 struct printf_spec spec = {0};
1461 str = (char *)bin_buf;
1462 end = (char *)(bin_buf + size);
1464 #define save_arg(type) \
1466 if (sizeof(type) == 8) { \
1467 unsigned long long value; \
1468 str = PTR_ALIGN(str, sizeof(u32)); \
1469 value = va_arg(args, unsigned long long); \
1470 if (str + sizeof(type) <= end) { \
1471 *(u32 *)str = *(u32 *)&value; \
1472 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1475 unsigned long value; \
1476 str = PTR_ALIGN(str, sizeof(type)); \
1477 value = va_arg(args, int); \
1478 if (str + sizeof(type) <= end) \
1479 *(typeof(type) *)str = (type)value; \
1481 str += sizeof(type); \
1485 int read = format_decode(fmt, &spec);
1489 switch (spec.type) {
1490 case FORMAT_TYPE_NONE:
1491 case FORMAT_TYPE_INVALID:
1492 case FORMAT_TYPE_PERCENT_CHAR:
1495 case FORMAT_TYPE_WIDTH:
1496 case FORMAT_TYPE_PRECISION:
1500 case FORMAT_TYPE_CHAR:
1504 case FORMAT_TYPE_STR: {
1505 const char *save_str = va_arg(args, char *);
1508 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1509 || (unsigned long)save_str < PAGE_SIZE)
1510 save_str = "(null)";
1511 len = strlen(save_str) + 1;
1512 if (str + len < end)
1513 memcpy(str, save_str, len);
1518 case FORMAT_TYPE_PTR:
1520 /* skip all alphanumeric pointer suffixes */
1521 while (isalnum(*fmt))
1525 case FORMAT_TYPE_NRCHARS: {
1526 /* skip %n 's argument */
1527 u8 qualifier = spec.qualifier;
1529 if (qualifier == 'l')
1530 skip_arg = va_arg(args, long *);
1531 else if (_tolower(qualifier) == 'z')
1532 skip_arg = va_arg(args, size_t *);
1534 skip_arg = va_arg(args, int *);
1539 switch (spec.type) {
1541 case FORMAT_TYPE_LONG_LONG:
1542 save_arg(long long);
1544 case FORMAT_TYPE_ULONG:
1545 case FORMAT_TYPE_LONG:
1546 save_arg(unsigned long);
1548 case FORMAT_TYPE_SIZE_T:
1551 case FORMAT_TYPE_PTRDIFF:
1552 save_arg(ptrdiff_t);
1554 case FORMAT_TYPE_UBYTE:
1555 case FORMAT_TYPE_BYTE:
1558 case FORMAT_TYPE_USHORT:
1559 case FORMAT_TYPE_SHORT:
1568 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1571 EXPORT_SYMBOL_GPL(vbin_printf);
1574 * bstr_printf - Format a string from binary arguments and place it in a buffer
1575 * @buf: The buffer to place the result into
1576 * @size: The size of the buffer, including the trailing null space
1577 * @fmt: The format string to use
1578 * @bin_buf: Binary arguments for the format string
1580 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1581 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1582 * a binary buffer that generated by vbin_printf.
1584 * The format follows C99 vsnprintf, but has some extensions:
1585 * see vsnprintf comment for details.
1587 * The return value is the number of characters which would
1588 * be generated for the given input, excluding the trailing
1589 * '\0', as per ISO C99. If you want to have the exact
1590 * number of characters written into @buf as return value
1591 * (not including the trailing '\0'), use vscnprintf(). If the
1592 * return is greater than or equal to @size, the resulting
1593 * string is truncated.
1595 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1597 struct printf_spec spec = {0};
1599 const char *args = (const char *)bin_buf;
1601 if (WARN_ON_ONCE((int) size < 0))
1607 #define get_arg(type) \
1609 typeof(type) value; \
1610 if (sizeof(type) == 8) { \
1611 args = PTR_ALIGN(args, sizeof(u32)); \
1612 *(u32 *)&value = *(u32 *)args; \
1613 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1615 args = PTR_ALIGN(args, sizeof(type)); \
1616 value = *(typeof(type) *)args; \
1618 args += sizeof(type); \
1622 /* Make sure end is always >= buf */
1629 const char *old_fmt = fmt;
1630 int read = format_decode(fmt, &spec);
1634 switch (spec.type) {
1635 case FORMAT_TYPE_NONE: {
1638 if (copy > end - str)
1640 memcpy(str, old_fmt, copy);
1646 case FORMAT_TYPE_WIDTH:
1647 spec.field_width = get_arg(int);
1650 case FORMAT_TYPE_PRECISION:
1651 spec.precision = get_arg(int);
1654 case FORMAT_TYPE_CHAR: {
1657 if (!(spec.flags & LEFT)) {
1658 while (--spec.field_width > 0) {
1664 c = (unsigned char) get_arg(char);
1668 while (--spec.field_width > 0) {
1676 case FORMAT_TYPE_STR: {
1677 const char *str_arg = args;
1678 args += strlen(str_arg) + 1;
1679 str = string(str, end, (char *)str_arg, spec);
1683 case FORMAT_TYPE_PTR:
1684 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1685 while (isalnum(*fmt))
1689 case FORMAT_TYPE_PERCENT_CHAR:
1690 case FORMAT_TYPE_INVALID:
1696 case FORMAT_TYPE_NRCHARS:
1701 unsigned long long num;
1703 switch (spec.type) {
1705 case FORMAT_TYPE_LONG_LONG:
1706 num = get_arg(long long);
1708 case FORMAT_TYPE_ULONG:
1709 case FORMAT_TYPE_LONG:
1710 num = get_arg(unsigned long);
1712 case FORMAT_TYPE_SIZE_T:
1713 num = get_arg(size_t);
1715 case FORMAT_TYPE_PTRDIFF:
1716 num = get_arg(ptrdiff_t);
1718 case FORMAT_TYPE_UBYTE:
1719 num = get_arg(unsigned char);
1721 case FORMAT_TYPE_BYTE:
1722 num = get_arg(signed char);
1724 case FORMAT_TYPE_USHORT:
1725 num = get_arg(unsigned short);
1727 case FORMAT_TYPE_SHORT:
1728 num = get_arg(short);
1730 case FORMAT_TYPE_UINT:
1731 num = get_arg(unsigned int);
1737 str = number(str, end, num, spec);
1739 } /* switch(spec.type) */
1751 /* the trailing null byte doesn't count towards the total */
1754 EXPORT_SYMBOL_GPL(bstr_printf);
1757 * bprintf - Parse a format string and place args' binary value in a buffer
1758 * @bin_buf: The buffer to place args' binary value
1759 * @size: The size of the buffer(by words(32bits), not characters)
1760 * @fmt: The format string to use
1761 * @...: Arguments for the format string
1763 * The function returns the number of words(u32) written
1766 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1771 va_start(args, fmt);
1772 ret = vbin_printf(bin_buf, size, fmt, args);
1777 EXPORT_SYMBOL_GPL(bprintf);
1779 #endif /* CONFIG_BINARY_PRINTF */
1782 * vsscanf - Unformat a buffer into a list of arguments
1783 * @buf: input buffer
1784 * @fmt: format of buffer
1787 int vsscanf(const char *buf, const char *fmt, va_list args)
1789 const char *str = buf;
1798 while (*fmt && *str) {
1799 /* skip any white space in format */
1800 /* white space in format matchs any amount of
1801 * white space, including none, in the input.
1803 if (isspace(*fmt)) {
1804 fmt = skip_spaces(++fmt);
1805 str = skip_spaces(str);
1808 /* anything that is not a conversion must match exactly */
1809 if (*fmt != '%' && *fmt) {
1810 if (*fmt++ != *str++)
1819 /* skip this conversion.
1820 * advance both strings to next white space
1823 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1825 while (!isspace(*str) && *str)
1830 /* get field width */
1833 field_width = skip_atoi(&fmt);
1835 /* get conversion qualifier */
1837 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1838 _tolower(*fmt) == 'z') {
1840 if (unlikely(qualifier == *fmt)) {
1841 if (qualifier == 'h') {
1844 } else if (qualifier == 'l') {
1860 char *s = (char *)va_arg(args, char*);
1861 if (field_width == -1)
1865 } while (--field_width > 0 && *str);
1871 char *s = (char *)va_arg(args, char *);
1872 if (field_width == -1)
1873 field_width = SHRT_MAX;
1874 /* first, skip leading white space in buffer */
1875 str = skip_spaces(str);
1877 /* now copy until next white space */
1878 while (*str && !isspace(*str) && field_width--)
1885 /* return number of characters read so far */
1887 int *i = (int *)va_arg(args, int*);
1905 /* looking for '%' in str */
1910 /* invalid format; stop here */
1914 /* have some sort of integer conversion.
1915 * first, skip white space in buffer.
1917 str = skip_spaces(str);
1920 if (is_sign && digit == '-')
1924 || (base == 16 && !isxdigit(digit))
1925 || (base == 10 && !isdigit(digit))
1926 || (base == 8 && (!isdigit(digit) || digit > '7'))
1927 || (base == 0 && !isdigit(digit)))
1930 switch (qualifier) {
1931 case 'H': /* that's 'hh' in format */
1933 signed char *s = (signed char *)va_arg(args, signed char *);
1934 *s = (signed char)simple_strtol(str, &next, base);
1936 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1937 *s = (unsigned char)simple_strtoul(str, &next, base);
1942 short *s = (short *)va_arg(args, short *);
1943 *s = (short)simple_strtol(str, &next, base);
1945 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1946 *s = (unsigned short)simple_strtoul(str, &next, base);
1951 long *l = (long *)va_arg(args, long *);
1952 *l = simple_strtol(str, &next, base);
1954 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1955 *l = simple_strtoul(str, &next, base);
1960 long long *l = (long long *)va_arg(args, long long *);
1961 *l = simple_strtoll(str, &next, base);
1963 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1964 *l = simple_strtoull(str, &next, base);
1970 size_t *s = (size_t *)va_arg(args, size_t *);
1971 *s = (size_t)simple_strtoul(str, &next, base);
1976 int *i = (int *)va_arg(args, int *);
1977 *i = (int)simple_strtol(str, &next, base);
1979 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
1980 *i = (unsigned int)simple_strtoul(str, &next, base);
1992 * Now we've come all the way through so either the input string or the
1993 * format ended. In the former case, there can be a %n at the current
1994 * position in the format that needs to be filled.
1996 if (*fmt == '%' && *(fmt + 1) == 'n') {
1997 int *p = (int *)va_arg(args, int *);
2003 EXPORT_SYMBOL(vsscanf);
2006 * sscanf - Unformat a buffer into a list of arguments
2007 * @buf: input buffer
2008 * @fmt: formatting of buffer
2009 * @...: resulting arguments
2011 int sscanf(const char *buf, const char *fmt, ...)
2016 va_start(args, fmt);
2017 i = vsscanf(buf, fmt, args);
2022 EXPORT_SYMBOL(sscanf);