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() */
34 /* Works only for digits and letters, but small and fast */
35 #define TOLOWER(x) ((x) | 0x20)
37 static unsigned int simple_guess_base(const char *cp)
40 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
50 * simple_strtoull - convert a string to an unsigned long long
51 * @cp: The start of the string
52 * @endp: A pointer to the end of the parsed string will be placed here
53 * @base: The number base to use
55 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
57 unsigned long long result = 0;
60 base = simple_guess_base(cp);
62 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
65 while (isxdigit(*cp)) {
68 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
71 result = result * base + value;
79 EXPORT_SYMBOL(simple_strtoull);
82 * simple_strtoul - convert a string to an unsigned long
83 * @cp: The start of the string
84 * @endp: A pointer to the end of the parsed string will be placed here
85 * @base: The number base to use
87 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
89 return simple_strtoull(cp, endp, base);
91 EXPORT_SYMBOL(simple_strtoul);
94 * simple_strtol - convert a string to a signed long
95 * @cp: The start of the string
96 * @endp: A pointer to the end of the parsed string will be placed here
97 * @base: The number base to use
99 long simple_strtol(const char *cp, char **endp, unsigned int base)
102 return -simple_strtoul(cp + 1, endp, base);
104 return simple_strtoul(cp, endp, base);
106 EXPORT_SYMBOL(simple_strtol);
109 * simple_strtoll - convert a string to a signed long long
110 * @cp: The start of the string
111 * @endp: A pointer to the end of the parsed string will be placed here
112 * @base: The number base to use
114 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
117 return -simple_strtoull(cp + 1, endp, base);
119 return simple_strtoull(cp, endp, base);
121 EXPORT_SYMBOL(simple_strtoll);
123 static noinline_for_stack
124 int skip_atoi(const char **s)
129 i = i*10 + *((*s)++) - '0';
134 /* Decimal conversion is by far the most typical, and is used
135 * for /proc and /sys data. This directly impacts e.g. top performance
136 * with many processes running. We optimize it for speed
138 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
139 * (with permission from the author, Douglas W. Jones). */
141 /* Formats correctly any integer in [0,99999].
142 * Outputs from one to five digits depending on input.
143 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
144 static noinline_for_stack
145 char *put_dec_trunc(char *buf, unsigned q)
147 unsigned d3, d2, d1, d0;
152 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
153 q = (d0 * 0xcd) >> 11;
155 *buf++ = d0 + '0'; /* least significant digit */
156 d1 = q + 9*d3 + 5*d2 + d1;
158 q = (d1 * 0xcd) >> 11;
160 *buf++ = d1 + '0'; /* next digit */
163 if ((d2 != 0) || (d3 != 0)) {
166 *buf++ = d2 + '0'; /* next digit */
170 q = (d3 * 0xcd) >> 11;
172 *buf++ = d3 + '0'; /* next digit */
174 *buf++ = q + '0'; /* most sign. digit */
181 /* Same with if's removed. Always emits five digits */
182 static noinline_for_stack
183 char *put_dec_full(char *buf, unsigned q)
185 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
186 /* but anyway, gcc produces better code with full-sized ints */
187 unsigned d3, d2, d1, d0;
193 * Possible ways to approx. divide by 10
194 * gcc -O2 replaces multiply with shifts and adds
195 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
196 * (x * 0x67) >> 10: 1100111
197 * (x * 0x34) >> 9: 110100 - same
198 * (x * 0x1a) >> 8: 11010 - same
199 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
201 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
202 q = (d0 * 0xcd) >> 11;
205 d1 = q + 9*d3 + 5*d2 + d1;
206 q = (d1 * 0xcd) >> 11;
216 q = (d3 * 0xcd) >> 11; /* - shorter code */
217 /* q = (d3 * 0x67) >> 10; - would also work */
224 /* No inlining helps gcc to use registers better */
225 static noinline_for_stack
226 char *put_dec(char *buf, unsigned long long num)
231 return put_dec_trunc(buf, num);
232 rem = do_div(num, 100000);
233 buf = put_dec_full(buf, rem);
237 #define ZEROPAD 1 /* pad with zero */
238 #define SIGN 2 /* unsigned/signed long */
239 #define PLUS 4 /* show plus */
240 #define SPACE 8 /* space if plus */
241 #define LEFT 16 /* left justified */
242 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
243 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
246 FORMAT_TYPE_NONE, /* Just a string part */
248 FORMAT_TYPE_PRECISION,
252 FORMAT_TYPE_PERCENT_CHAR,
254 FORMAT_TYPE_LONG_LONG,
269 u8 type; /* format_type enum */
270 u8 flags; /* flags to number() */
271 u8 base; /* number base, 8, 10 or 16 only */
272 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
273 s16 field_width; /* width of output field */
274 s16 precision; /* # of digits/chars */
277 static noinline_for_stack
278 char *number(char *buf, char *end, unsigned long long num,
279 struct printf_spec spec)
281 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
282 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
287 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
290 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
291 * produces same digits or (maybe lowercased) letters */
292 locase = (spec.flags & SMALL);
293 if (spec.flags & LEFT)
294 spec.flags &= ~ZEROPAD;
296 if (spec.flags & SIGN) {
297 if ((signed long long)num < 0) {
299 num = -(signed long long)num;
301 } else if (spec.flags & PLUS) {
304 } else if (spec.flags & SPACE) {
315 /* generate full string in tmp[], in reverse order */
319 /* Generic code, for any base:
321 tmp[i++] = (digits[do_div(num,base)] | locase);
324 else if (spec.base != 10) { /* 8 or 16 */
325 int mask = spec.base - 1;
331 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
334 } else { /* base 10 */
335 i = put_dec(tmp, num) - tmp;
338 /* printing 100 using %2d gives "100", not "00" */
339 if (i > spec.precision)
341 /* leading space padding */
342 spec.field_width -= spec.precision;
343 if (!(spec.flags & (ZEROPAD+LEFT))) {
344 while (--spec.field_width >= 0) {
356 /* "0x" / "0" prefix */
361 if (spec.base == 16) {
363 *buf = ('X' | locase);
367 /* zero or space padding */
368 if (!(spec.flags & LEFT)) {
369 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
370 while (--spec.field_width >= 0) {
376 /* hmm even more zero padding? */
377 while (i <= --spec.precision) {
382 /* actual digits of result */
388 /* trailing space padding */
389 while (--spec.field_width >= 0) {
398 static noinline_for_stack
399 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
403 if ((unsigned long)s < PAGE_SIZE)
406 len = strnlen(s, spec.precision);
408 if (!(spec.flags & LEFT)) {
409 while (len < spec.field_width--) {
415 for (i = 0; i < len; ++i) {
420 while (len < spec.field_width--) {
429 static noinline_for_stack
430 char *symbol_string(char *buf, char *end, void *ptr,
431 struct printf_spec spec, char ext)
433 unsigned long value = (unsigned long) ptr;
434 #ifdef CONFIG_KALLSYMS
435 char sym[KSYM_SYMBOL_LEN];
437 sprint_backtrace(sym, value);
438 else if (ext != 'f' && ext != 's')
439 sprint_symbol(sym, value);
441 kallsyms_lookup(value, NULL, NULL, NULL, sym);
443 return string(buf, end, sym, spec);
445 spec.field_width = 2 * sizeof(void *);
446 spec.flags |= SPECIAL | SMALL | ZEROPAD;
449 return number(buf, end, value, spec);
453 static noinline_for_stack
454 char *resource_string(char *buf, char *end, struct resource *res,
455 struct printf_spec spec, const char *fmt)
457 #ifndef IO_RSRC_PRINTK_SIZE
458 #define IO_RSRC_PRINTK_SIZE 6
461 #ifndef MEM_RSRC_PRINTK_SIZE
462 #define MEM_RSRC_PRINTK_SIZE 10
464 static const struct printf_spec io_spec = {
466 .field_width = IO_RSRC_PRINTK_SIZE,
468 .flags = SPECIAL | SMALL | ZEROPAD,
470 static const struct printf_spec mem_spec = {
472 .field_width = MEM_RSRC_PRINTK_SIZE,
474 .flags = SPECIAL | SMALL | ZEROPAD,
476 static const struct printf_spec bus_spec = {
480 .flags = SMALL | ZEROPAD,
482 static const struct printf_spec dec_spec = {
487 static const struct printf_spec str_spec = {
492 static const struct printf_spec flag_spec = {
495 .flags = SPECIAL | SMALL,
498 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
499 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
500 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
501 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
502 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
503 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
504 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
505 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
507 char *p = sym, *pend = sym + sizeof(sym);
508 int decode = (fmt[0] == 'R') ? 1 : 0;
509 const struct printf_spec *specp;
512 if (res->flags & IORESOURCE_IO) {
513 p = string(p, pend, "io ", str_spec);
515 } else if (res->flags & IORESOURCE_MEM) {
516 p = string(p, pend, "mem ", str_spec);
518 } else if (res->flags & IORESOURCE_IRQ) {
519 p = string(p, pend, "irq ", str_spec);
521 } else if (res->flags & IORESOURCE_DMA) {
522 p = string(p, pend, "dma ", str_spec);
524 } else if (res->flags & IORESOURCE_BUS) {
525 p = string(p, pend, "bus ", str_spec);
528 p = string(p, pend, "??? ", str_spec);
532 p = number(p, pend, res->start, *specp);
533 if (res->start != res->end) {
535 p = number(p, pend, res->end, *specp);
538 if (res->flags & IORESOURCE_MEM_64)
539 p = string(p, pend, " 64bit", str_spec);
540 if (res->flags & IORESOURCE_PREFETCH)
541 p = string(p, pend, " pref", str_spec);
542 if (res->flags & IORESOURCE_WINDOW)
543 p = string(p, pend, " window", str_spec);
544 if (res->flags & IORESOURCE_DISABLED)
545 p = string(p, pend, " disabled", str_spec);
547 p = string(p, pend, " flags ", str_spec);
548 p = number(p, pend, res->flags, flag_spec);
553 return string(buf, end, sym, spec);
556 static noinline_for_stack
557 char *mac_address_string(char *buf, char *end, u8 *addr,
558 struct printf_spec spec, const char *fmt)
560 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
565 if (fmt[1] == 'F') { /* FDDI canonical format */
571 for (i = 0; i < 6; i++) {
572 p = pack_hex_byte(p, addr[i]);
573 if (fmt[0] == 'M' && i != 5)
578 return string(buf, end, mac_addr, spec);
581 static noinline_for_stack
582 char *ip4_string(char *p, const u8 *addr, const char *fmt)
585 bool leading_zeros = (fmt[0] == 'i');
610 for (i = 0; i < 4; i++) {
611 char temp[3]; /* hold each IP quad in reverse order */
612 int digits = put_dec_trunc(temp, addr[index]) - temp;
619 /* reverse the digits in the quad */
631 static noinline_for_stack
632 char *ip6_compressed_string(char *p, const char *addr)
635 unsigned char zerolength[8];
640 bool needcolon = false;
644 memcpy(&in6, addr, sizeof(struct in6_addr));
646 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
648 memset(zerolength, 0, sizeof(zerolength));
655 /* find position of longest 0 run */
656 for (i = 0; i < range; i++) {
657 for (j = i; j < range; j++) {
658 if (in6.s6_addr16[j] != 0)
663 for (i = 0; i < range; i++) {
664 if (zerolength[i] > longest) {
665 longest = zerolength[i];
669 if (longest == 1) /* don't compress a single 0 */
673 for (i = 0; i < range; i++) {
675 if (needcolon || i == 0)
686 /* hex u16 without leading 0s */
687 word = ntohs(in6.s6_addr16[i]);
692 p = pack_hex_byte(p, hi);
694 *p++ = hex_asc_lo(hi);
695 p = pack_hex_byte(p, lo);
698 p = pack_hex_byte(p, lo);
700 *p++ = hex_asc_lo(lo);
707 p = ip4_string(p, &in6.s6_addr[12], "I4");
714 static noinline_for_stack
715 char *ip6_string(char *p, const char *addr, const char *fmt)
719 for (i = 0; i < 8; i++) {
720 p = pack_hex_byte(p, *addr++);
721 p = pack_hex_byte(p, *addr++);
722 if (fmt[0] == 'I' && i != 7)
730 static noinline_for_stack
731 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
732 struct printf_spec spec, const char *fmt)
734 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
736 if (fmt[0] == 'I' && fmt[2] == 'c')
737 ip6_compressed_string(ip6_addr, addr);
739 ip6_string(ip6_addr, addr, fmt);
741 return string(buf, end, ip6_addr, spec);
744 static noinline_for_stack
745 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
746 struct printf_spec spec, const char *fmt)
748 char ip4_addr[sizeof("255.255.255.255")];
750 ip4_string(ip4_addr, addr, fmt);
752 return string(buf, end, ip4_addr, spec);
755 static noinline_for_stack
756 char *uuid_string(char *buf, char *end, const u8 *addr,
757 struct printf_spec spec, const char *fmt)
759 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
762 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
763 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
764 const u8 *index = be;
769 uc = true; /* fall-through */
778 for (i = 0; i < 16; i++) {
779 p = pack_hex_byte(p, addr[index[i]]);
799 return string(buf, end, uuid, spec);
802 int kptr_restrict __read_mostly;
805 * Show a '%p' thing. A kernel extension is that the '%p' is followed
806 * by an extra set of alphanumeric characters that are extended format
809 * Right now we handle:
811 * - 'F' For symbolic function descriptor pointers with offset
812 * - 'f' For simple symbolic function names without offset
813 * - 'S' For symbolic direct pointers with offset
814 * - 's' For symbolic direct pointers without offset
815 * - 'B' For backtraced symbolic direct pointers with offset
816 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
817 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
818 * - 'M' For a 6-byte MAC address, it prints the address in the
819 * usual colon-separated hex notation
820 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
821 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
822 * with a dash-separated hex notation
823 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
824 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
825 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
826 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
827 * IPv6 omits the colons (01020304...0f)
828 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
829 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
830 * - 'I6c' for IPv6 addresses printed as specified by
831 * http://tools.ietf.org/html/rfc5952
832 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
833 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
834 * Options for %pU are:
835 * b big endian lower case hex (default)
836 * B big endian UPPER case hex
837 * l little endian lower case hex
838 * L little endian UPPER case hex
839 * big endian output byte order is:
840 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
841 * little endian output byte order is:
842 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
843 * - 'V' For a struct va_format which contains a format string * and va_list *,
844 * call vsnprintf(->format, *->va_list).
845 * Implements a "recursive vsnprintf".
846 * Do not use this feature without some mechanism to verify the
847 * correctness of the format string and va_list arguments.
848 * - 'K' For a kernel pointer that should be hidden from unprivileged users
850 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
851 * function pointers are really function descriptors, which contain a
852 * pointer to the real address.
854 static noinline_for_stack
855 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
856 struct printf_spec spec)
858 if (!ptr && *fmt != 'K') {
860 * Print (null) with the same width as a pointer so it makes
861 * tabular output look nice.
863 if (spec.field_width == -1)
864 spec.field_width = 2 * sizeof(void *);
865 return string(buf, end, "(null)", spec);
871 ptr = dereference_function_descriptor(ptr);
876 return symbol_string(buf, end, ptr, spec, *fmt);
879 return resource_string(buf, end, ptr, spec, fmt);
880 case 'M': /* Colon separated: 00:01:02:03:04:05 */
881 case 'm': /* Contiguous: 000102030405 */
882 /* [mM]F (FDDI, bit reversed) */
883 return mac_address_string(buf, end, ptr, spec, fmt);
884 case 'I': /* Formatted IP supported
886 * 6: 0001:0203:...:0708
887 * 6c: 1::708 or 1::1.2.3.4
889 case 'i': /* Contiguous:
895 return ip6_addr_string(buf, end, ptr, spec, fmt);
897 return ip4_addr_string(buf, end, ptr, spec, fmt);
901 return uuid_string(buf, end, ptr, spec, fmt);
903 return buf + vsnprintf(buf, end > buf ? end - buf : 0,
904 ((struct va_format *)ptr)->fmt,
905 *(((struct va_format *)ptr)->va));
908 * %pK cannot be used in IRQ context because its test
909 * for CAP_SYSLOG would be meaningless.
911 if (in_irq() || in_serving_softirq() || in_nmi()) {
912 if (spec.field_width == -1)
913 spec.field_width = 2 * sizeof(void *);
914 return string(buf, end, "pK-error", spec);
916 if (!((kptr_restrict == 0) ||
917 (kptr_restrict == 1 &&
918 has_capability_noaudit(current, CAP_SYSLOG))))
923 if (spec.field_width == -1) {
924 spec.field_width = 2 * sizeof(void *);
925 spec.flags |= ZEROPAD;
929 return number(buf, end, (unsigned long) ptr, spec);
933 * Helper function to decode printf style format.
934 * Each call decode a token from the format and return the
935 * number of characters read (or likely the delta where it wants
936 * to go on the next call).
937 * The decoded token is returned through the parameters
939 * 'h', 'l', or 'L' for integer fields
940 * 'z' support added 23/7/1999 S.H.
941 * 'z' changed to 'Z' --davidm 1/25/99
942 * 't' added for ptrdiff_t
944 * @fmt: the format string
945 * @type of the token returned
946 * @flags: various flags such as +, -, # tokens..
947 * @field_width: overwritten width
948 * @base: base of the number (octal, hex, ...)
949 * @precision: precision of a number
950 * @qualifier: qualifier of a number (long, size_t, ...)
952 static noinline_for_stack
953 int format_decode(const char *fmt, struct printf_spec *spec)
955 const char *start = fmt;
957 /* we finished early by reading the field width */
958 if (spec->type == FORMAT_TYPE_WIDTH) {
959 if (spec->field_width < 0) {
960 spec->field_width = -spec->field_width;
963 spec->type = FORMAT_TYPE_NONE;
967 /* we finished early by reading the precision */
968 if (spec->type == FORMAT_TYPE_PRECISION) {
969 if (spec->precision < 0)
972 spec->type = FORMAT_TYPE_NONE;
977 spec->type = FORMAT_TYPE_NONE;
979 for (; *fmt ; ++fmt) {
984 /* Return the current non-format string */
985 if (fmt != start || !*fmt)
991 while (1) { /* this also skips first '%' */
997 case '-': spec->flags |= LEFT; break;
998 case '+': spec->flags |= PLUS; break;
999 case ' ': spec->flags |= SPACE; break;
1000 case '#': spec->flags |= SPECIAL; break;
1001 case '0': spec->flags |= ZEROPAD; break;
1002 default: found = false;
1009 /* get field width */
1010 spec->field_width = -1;
1013 spec->field_width = skip_atoi(&fmt);
1014 else if (*fmt == '*') {
1015 /* it's the next argument */
1016 spec->type = FORMAT_TYPE_WIDTH;
1017 return ++fmt - start;
1021 /* get the precision */
1022 spec->precision = -1;
1025 if (isdigit(*fmt)) {
1026 spec->precision = skip_atoi(&fmt);
1027 if (spec->precision < 0)
1028 spec->precision = 0;
1029 } else if (*fmt == '*') {
1030 /* it's the next argument */
1031 spec->type = FORMAT_TYPE_PRECISION;
1032 return ++fmt - start;
1037 /* get the conversion qualifier */
1038 spec->qualifier = -1;
1039 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1040 TOLOWER(*fmt) == 'z' || *fmt == 't') {
1041 spec->qualifier = *fmt++;
1042 if (unlikely(spec->qualifier == *fmt)) {
1043 if (spec->qualifier == 'l') {
1044 spec->qualifier = 'L';
1046 } else if (spec->qualifier == 'h') {
1047 spec->qualifier = 'H';
1057 spec->type = FORMAT_TYPE_CHAR;
1058 return ++fmt - start;
1061 spec->type = FORMAT_TYPE_STR;
1062 return ++fmt - start;
1065 spec->type = FORMAT_TYPE_PTR;
1070 spec->type = FORMAT_TYPE_NRCHARS;
1071 return ++fmt - start;
1074 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1075 return ++fmt - start;
1077 /* integer number formats - set up the flags and "break" */
1083 spec->flags |= SMALL;
1091 spec->flags |= SIGN;
1096 spec->type = FORMAT_TYPE_INVALID;
1100 if (spec->qualifier == 'L')
1101 spec->type = FORMAT_TYPE_LONG_LONG;
1102 else if (spec->qualifier == 'l') {
1103 if (spec->flags & SIGN)
1104 spec->type = FORMAT_TYPE_LONG;
1106 spec->type = FORMAT_TYPE_ULONG;
1107 } else if (TOLOWER(spec->qualifier) == 'z') {
1108 spec->type = FORMAT_TYPE_SIZE_T;
1109 } else if (spec->qualifier == 't') {
1110 spec->type = FORMAT_TYPE_PTRDIFF;
1111 } else if (spec->qualifier == 'H') {
1112 if (spec->flags & SIGN)
1113 spec->type = FORMAT_TYPE_BYTE;
1115 spec->type = FORMAT_TYPE_UBYTE;
1116 } else if (spec->qualifier == 'h') {
1117 if (spec->flags & SIGN)
1118 spec->type = FORMAT_TYPE_SHORT;
1120 spec->type = FORMAT_TYPE_USHORT;
1122 if (spec->flags & SIGN)
1123 spec->type = FORMAT_TYPE_INT;
1125 spec->type = FORMAT_TYPE_UINT;
1128 return ++fmt - start;
1132 * vsnprintf - Format a string and place it in a buffer
1133 * @buf: The buffer to place the result into
1134 * @size: The size of the buffer, including the trailing null space
1135 * @fmt: The format string to use
1136 * @args: Arguments for the format string
1138 * This function follows C99 vsnprintf, but has some extensions:
1139 * %pS output the name of a text symbol with offset
1140 * %ps output the name of a text symbol without offset
1141 * %pF output the name of a function pointer with its offset
1142 * %pf output the name of a function pointer without its offset
1143 * %pB output the name of a backtrace symbol with its offset
1144 * %pR output the address range in a struct resource with decoded flags
1145 * %pr output the address range in a struct resource with raw flags
1146 * %pM output a 6-byte MAC address with colons
1147 * %pm output a 6-byte MAC address without colons
1148 * %pI4 print an IPv4 address without leading zeros
1149 * %pi4 print an IPv4 address with leading zeros
1150 * %pI6 print an IPv6 address with colons
1151 * %pi6 print an IPv6 address without colons
1152 * %pI6c print an IPv6 address as specified by RFC 5952
1153 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1157 * The return value is the number of characters which would
1158 * be generated for the given input, excluding the trailing
1159 * '\0', as per ISO C99. If you want to have the exact
1160 * number of characters written into @buf as return value
1161 * (not including the trailing '\0'), use vscnprintf(). If the
1162 * return is greater than or equal to @size, the resulting
1163 * string is truncated.
1165 * If you're not already dealing with a va_list consider using snprintf().
1167 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1169 unsigned long long num;
1171 struct printf_spec spec = {0};
1173 /* Reject out-of-range values early. Large positive sizes are
1174 used for unknown buffer sizes. */
1175 if (WARN_ON_ONCE((int) size < 0))
1181 /* Make sure end is always >= buf */
1188 const char *old_fmt = fmt;
1189 int read = format_decode(fmt, &spec);
1193 switch (spec.type) {
1194 case FORMAT_TYPE_NONE: {
1197 if (copy > end - str)
1199 memcpy(str, old_fmt, copy);
1205 case FORMAT_TYPE_WIDTH:
1206 spec.field_width = va_arg(args, int);
1209 case FORMAT_TYPE_PRECISION:
1210 spec.precision = va_arg(args, int);
1213 case FORMAT_TYPE_CHAR: {
1216 if (!(spec.flags & LEFT)) {
1217 while (--spec.field_width > 0) {
1224 c = (unsigned char) va_arg(args, int);
1228 while (--spec.field_width > 0) {
1236 case FORMAT_TYPE_STR:
1237 str = string(str, end, va_arg(args, char *), spec);
1240 case FORMAT_TYPE_PTR:
1241 str = pointer(fmt+1, str, end, va_arg(args, void *),
1243 while (isalnum(*fmt))
1247 case FORMAT_TYPE_PERCENT_CHAR:
1253 case FORMAT_TYPE_INVALID:
1259 case FORMAT_TYPE_NRCHARS: {
1260 u8 qualifier = spec.qualifier;
1262 if (qualifier == 'l') {
1263 long *ip = va_arg(args, long *);
1265 } else if (TOLOWER(qualifier) == 'z') {
1266 size_t *ip = va_arg(args, size_t *);
1269 int *ip = va_arg(args, int *);
1276 switch (spec.type) {
1277 case FORMAT_TYPE_LONG_LONG:
1278 num = va_arg(args, long long);
1280 case FORMAT_TYPE_ULONG:
1281 num = va_arg(args, unsigned long);
1283 case FORMAT_TYPE_LONG:
1284 num = va_arg(args, long);
1286 case FORMAT_TYPE_SIZE_T:
1287 num = va_arg(args, size_t);
1289 case FORMAT_TYPE_PTRDIFF:
1290 num = va_arg(args, ptrdiff_t);
1292 case FORMAT_TYPE_UBYTE:
1293 num = (unsigned char) va_arg(args, int);
1295 case FORMAT_TYPE_BYTE:
1296 num = (signed char) va_arg(args, int);
1298 case FORMAT_TYPE_USHORT:
1299 num = (unsigned short) va_arg(args, int);
1301 case FORMAT_TYPE_SHORT:
1302 num = (short) va_arg(args, int);
1304 case FORMAT_TYPE_INT:
1305 num = (int) va_arg(args, int);
1308 num = va_arg(args, unsigned int);
1311 str = number(str, end, num, spec);
1322 /* the trailing null byte doesn't count towards the total */
1326 EXPORT_SYMBOL(vsnprintf);
1329 * vscnprintf - Format a string and place it in a buffer
1330 * @buf: The buffer to place the result into
1331 * @size: The size of the buffer, including the trailing null space
1332 * @fmt: The format string to use
1333 * @args: Arguments for the format string
1335 * The return value is the number of characters which have been written into
1336 * the @buf not including the trailing '\0'. If @size is == 0 the function
1339 * If you're not already dealing with a va_list consider using scnprintf().
1341 * See the vsnprintf() documentation for format string extensions over C99.
1343 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1347 i = vsnprintf(buf, size, fmt, args);
1349 if (likely(i < size))
1355 EXPORT_SYMBOL(vscnprintf);
1358 * snprintf - Format a string and place it in a buffer
1359 * @buf: The buffer to place the result into
1360 * @size: The size of the buffer, including the trailing null space
1361 * @fmt: The format string to use
1362 * @...: Arguments for the format string
1364 * The return value is the number of characters which would be
1365 * generated for the given input, excluding the trailing null,
1366 * as per ISO C99. If the return is greater than or equal to
1367 * @size, the resulting string is truncated.
1369 * See the vsnprintf() documentation for format string extensions over C99.
1371 int snprintf(char *buf, size_t size, const char *fmt, ...)
1376 va_start(args, fmt);
1377 i = vsnprintf(buf, size, fmt, args);
1382 EXPORT_SYMBOL(snprintf);
1385 * scnprintf - Format a string and place it in a buffer
1386 * @buf: The buffer to place the result into
1387 * @size: The size of the buffer, including the trailing null space
1388 * @fmt: The format string to use
1389 * @...: Arguments for the format string
1391 * The return value is the number of characters written into @buf not including
1392 * the trailing '\0'. If @size is == 0 the function returns 0.
1395 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1400 va_start(args, fmt);
1401 i = vscnprintf(buf, size, fmt, args);
1406 EXPORT_SYMBOL(scnprintf);
1409 * vsprintf - Format a string and place it in a buffer
1410 * @buf: The buffer to place the result into
1411 * @fmt: The format string to use
1412 * @args: Arguments for the format string
1414 * The function returns the number of characters written
1415 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1418 * If you're not already dealing with a va_list consider using sprintf().
1420 * See the vsnprintf() documentation for format string extensions over C99.
1422 int vsprintf(char *buf, const char *fmt, va_list args)
1424 return vsnprintf(buf, INT_MAX, fmt, args);
1426 EXPORT_SYMBOL(vsprintf);
1429 * sprintf - Format a string and place it in a buffer
1430 * @buf: The buffer to place the result into
1431 * @fmt: The format string to use
1432 * @...: Arguments for the format string
1434 * The function returns the number of characters written
1435 * into @buf. Use snprintf() or scnprintf() in order to avoid
1438 * See the vsnprintf() documentation for format string extensions over C99.
1440 int sprintf(char *buf, const char *fmt, ...)
1445 va_start(args, fmt);
1446 i = vsnprintf(buf, INT_MAX, fmt, args);
1451 EXPORT_SYMBOL(sprintf);
1453 #ifdef CONFIG_BINARY_PRINTF
1456 * vbin_printf() - VA arguments to binary data
1457 * bstr_printf() - Binary data to text string
1461 * vbin_printf - Parse a format string and place args' binary value in a buffer
1462 * @bin_buf: The buffer to place args' binary value
1463 * @size: The size of the buffer(by words(32bits), not characters)
1464 * @fmt: The format string to use
1465 * @args: Arguments for the format string
1467 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1470 * The return value is the number of words(32bits) which would be generated for
1474 * If the return value is greater than @size, the resulting bin_buf is NOT
1475 * valid for bstr_printf().
1477 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1479 struct printf_spec spec = {0};
1482 str = (char *)bin_buf;
1483 end = (char *)(bin_buf + size);
1485 #define save_arg(type) \
1487 if (sizeof(type) == 8) { \
1488 unsigned long long value; \
1489 str = PTR_ALIGN(str, sizeof(u32)); \
1490 value = va_arg(args, unsigned long long); \
1491 if (str + sizeof(type) <= end) { \
1492 *(u32 *)str = *(u32 *)&value; \
1493 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1496 unsigned long value; \
1497 str = PTR_ALIGN(str, sizeof(type)); \
1498 value = va_arg(args, int); \
1499 if (str + sizeof(type) <= end) \
1500 *(typeof(type) *)str = (type)value; \
1502 str += sizeof(type); \
1506 int read = format_decode(fmt, &spec);
1510 switch (spec.type) {
1511 case FORMAT_TYPE_NONE:
1512 case FORMAT_TYPE_INVALID:
1513 case FORMAT_TYPE_PERCENT_CHAR:
1516 case FORMAT_TYPE_WIDTH:
1517 case FORMAT_TYPE_PRECISION:
1521 case FORMAT_TYPE_CHAR:
1525 case FORMAT_TYPE_STR: {
1526 const char *save_str = va_arg(args, char *);
1529 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1530 || (unsigned long)save_str < PAGE_SIZE)
1531 save_str = "(null)";
1532 len = strlen(save_str) + 1;
1533 if (str + len < end)
1534 memcpy(str, save_str, len);
1539 case FORMAT_TYPE_PTR:
1541 /* skip all alphanumeric pointer suffixes */
1542 while (isalnum(*fmt))
1546 case FORMAT_TYPE_NRCHARS: {
1547 /* skip %n 's argument */
1548 u8 qualifier = spec.qualifier;
1550 if (qualifier == 'l')
1551 skip_arg = va_arg(args, long *);
1552 else if (TOLOWER(qualifier) == 'z')
1553 skip_arg = va_arg(args, size_t *);
1555 skip_arg = va_arg(args, int *);
1560 switch (spec.type) {
1562 case FORMAT_TYPE_LONG_LONG:
1563 save_arg(long long);
1565 case FORMAT_TYPE_ULONG:
1566 case FORMAT_TYPE_LONG:
1567 save_arg(unsigned long);
1569 case FORMAT_TYPE_SIZE_T:
1572 case FORMAT_TYPE_PTRDIFF:
1573 save_arg(ptrdiff_t);
1575 case FORMAT_TYPE_UBYTE:
1576 case FORMAT_TYPE_BYTE:
1579 case FORMAT_TYPE_USHORT:
1580 case FORMAT_TYPE_SHORT:
1589 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1592 EXPORT_SYMBOL_GPL(vbin_printf);
1595 * bstr_printf - Format a string from binary arguments and place it in a buffer
1596 * @buf: The buffer to place the result into
1597 * @size: The size of the buffer, including the trailing null space
1598 * @fmt: The format string to use
1599 * @bin_buf: Binary arguments for the format string
1601 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1602 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1603 * a binary buffer that generated by vbin_printf.
1605 * The format follows C99 vsnprintf, but has some extensions:
1606 * see vsnprintf comment for details.
1608 * The return value is the number of characters which would
1609 * be generated for the given input, excluding the trailing
1610 * '\0', as per ISO C99. If you want to have the exact
1611 * number of characters written into @buf as return value
1612 * (not including the trailing '\0'), use vscnprintf(). If the
1613 * return is greater than or equal to @size, the resulting
1614 * string is truncated.
1616 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1618 struct printf_spec spec = {0};
1620 const char *args = (const char *)bin_buf;
1622 if (WARN_ON_ONCE((int) size < 0))
1628 #define get_arg(type) \
1630 typeof(type) value; \
1631 if (sizeof(type) == 8) { \
1632 args = PTR_ALIGN(args, sizeof(u32)); \
1633 *(u32 *)&value = *(u32 *)args; \
1634 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1636 args = PTR_ALIGN(args, sizeof(type)); \
1637 value = *(typeof(type) *)args; \
1639 args += sizeof(type); \
1643 /* Make sure end is always >= buf */
1650 const char *old_fmt = fmt;
1651 int read = format_decode(fmt, &spec);
1655 switch (spec.type) {
1656 case FORMAT_TYPE_NONE: {
1659 if (copy > end - str)
1661 memcpy(str, old_fmt, copy);
1667 case FORMAT_TYPE_WIDTH:
1668 spec.field_width = get_arg(int);
1671 case FORMAT_TYPE_PRECISION:
1672 spec.precision = get_arg(int);
1675 case FORMAT_TYPE_CHAR: {
1678 if (!(spec.flags & LEFT)) {
1679 while (--spec.field_width > 0) {
1685 c = (unsigned char) get_arg(char);
1689 while (--spec.field_width > 0) {
1697 case FORMAT_TYPE_STR: {
1698 const char *str_arg = args;
1699 args += strlen(str_arg) + 1;
1700 str = string(str, end, (char *)str_arg, spec);
1704 case FORMAT_TYPE_PTR:
1705 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1706 while (isalnum(*fmt))
1710 case FORMAT_TYPE_PERCENT_CHAR:
1711 case FORMAT_TYPE_INVALID:
1717 case FORMAT_TYPE_NRCHARS:
1722 unsigned long long num;
1724 switch (spec.type) {
1726 case FORMAT_TYPE_LONG_LONG:
1727 num = get_arg(long long);
1729 case FORMAT_TYPE_ULONG:
1730 case FORMAT_TYPE_LONG:
1731 num = get_arg(unsigned long);
1733 case FORMAT_TYPE_SIZE_T:
1734 num = get_arg(size_t);
1736 case FORMAT_TYPE_PTRDIFF:
1737 num = get_arg(ptrdiff_t);
1739 case FORMAT_TYPE_UBYTE:
1740 num = get_arg(unsigned char);
1742 case FORMAT_TYPE_BYTE:
1743 num = get_arg(signed char);
1745 case FORMAT_TYPE_USHORT:
1746 num = get_arg(unsigned short);
1748 case FORMAT_TYPE_SHORT:
1749 num = get_arg(short);
1751 case FORMAT_TYPE_UINT:
1752 num = get_arg(unsigned int);
1758 str = number(str, end, num, spec);
1760 } /* switch(spec.type) */
1772 /* the trailing null byte doesn't count towards the total */
1775 EXPORT_SYMBOL_GPL(bstr_printf);
1778 * bprintf - Parse a format string and place args' binary value in a buffer
1779 * @bin_buf: The buffer to place args' binary value
1780 * @size: The size of the buffer(by words(32bits), not characters)
1781 * @fmt: The format string to use
1782 * @...: Arguments for the format string
1784 * The function returns the number of words(u32) written
1787 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1792 va_start(args, fmt);
1793 ret = vbin_printf(bin_buf, size, fmt, args);
1798 EXPORT_SYMBOL_GPL(bprintf);
1800 #endif /* CONFIG_BINARY_PRINTF */
1803 * vsscanf - Unformat a buffer into a list of arguments
1804 * @buf: input buffer
1805 * @fmt: format of buffer
1808 int vsscanf(const char *buf, const char *fmt, va_list args)
1810 const char *str = buf;
1819 while (*fmt && *str) {
1820 /* skip any white space in format */
1821 /* white space in format matchs any amount of
1822 * white space, including none, in the input.
1824 if (isspace(*fmt)) {
1825 fmt = skip_spaces(++fmt);
1826 str = skip_spaces(str);
1829 /* anything that is not a conversion must match exactly */
1830 if (*fmt != '%' && *fmt) {
1831 if (*fmt++ != *str++)
1840 /* skip this conversion.
1841 * advance both strings to next white space
1844 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1846 while (!isspace(*str) && *str)
1851 /* get field width */
1854 field_width = skip_atoi(&fmt);
1856 /* get conversion qualifier */
1858 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1859 TOLOWER(*fmt) == 'z') {
1861 if (unlikely(qualifier == *fmt)) {
1862 if (qualifier == 'h') {
1865 } else if (qualifier == 'l') {
1881 char *s = (char *)va_arg(args, char*);
1882 if (field_width == -1)
1886 } while (--field_width > 0 && *str);
1892 char *s = (char *)va_arg(args, char *);
1893 if (field_width == -1)
1894 field_width = SHRT_MAX;
1895 /* first, skip leading white space in buffer */
1896 str = skip_spaces(str);
1898 /* now copy until next white space */
1899 while (*str && !isspace(*str) && field_width--)
1906 /* return number of characters read so far */
1908 int *i = (int *)va_arg(args, int*);
1926 /* looking for '%' in str */
1931 /* invalid format; stop here */
1935 /* have some sort of integer conversion.
1936 * first, skip white space in buffer.
1938 str = skip_spaces(str);
1941 if (is_sign && digit == '-')
1945 || (base == 16 && !isxdigit(digit))
1946 || (base == 10 && !isdigit(digit))
1947 || (base == 8 && (!isdigit(digit) || digit > '7'))
1948 || (base == 0 && !isdigit(digit)))
1951 switch (qualifier) {
1952 case 'H': /* that's 'hh' in format */
1954 signed char *s = (signed char *)va_arg(args, signed char *);
1955 *s = (signed char)simple_strtol(str, &next, base);
1957 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1958 *s = (unsigned char)simple_strtoul(str, &next, base);
1963 short *s = (short *)va_arg(args, short *);
1964 *s = (short)simple_strtol(str, &next, base);
1966 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1967 *s = (unsigned short)simple_strtoul(str, &next, base);
1972 long *l = (long *)va_arg(args, long *);
1973 *l = simple_strtol(str, &next, base);
1975 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1976 *l = simple_strtoul(str, &next, base);
1981 long long *l = (long long *)va_arg(args, long long *);
1982 *l = simple_strtoll(str, &next, base);
1984 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1985 *l = simple_strtoull(str, &next, base);
1991 size_t *s = (size_t *)va_arg(args, size_t *);
1992 *s = (size_t)simple_strtoul(str, &next, base);
1997 int *i = (int *)va_arg(args, int *);
1998 *i = (int)simple_strtol(str, &next, base);
2000 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2001 *i = (unsigned int)simple_strtoul(str, &next, base);
2013 * Now we've come all the way through so either the input string or the
2014 * format ended. In the former case, there can be a %n at the current
2015 * position in the format that needs to be filled.
2017 if (*fmt == '%' && *(fmt + 1) == 'n') {
2018 int *p = (int *)va_arg(args, int *);
2024 EXPORT_SYMBOL(vsscanf);
2027 * sscanf - Unformat a buffer into a list of arguments
2028 * @buf: input buffer
2029 * @fmt: formatting of buffer
2030 * @...: resulting arguments
2032 int sscanf(const char *buf, const char *fmt, ...)
2037 va_start(args, fmt);
2038 i = vsscanf(buf, fmt, args);
2043 EXPORT_SYMBOL(sscanf);