4 * Copyright (C) 1991, 1992 Linus Torvalds
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
16 * - scnprintf and vscnprintf
20 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/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);
216 * Convert passed number to decimal string.
217 * Returns the length of string. On buffer overflow, returns 0.
219 * If speed is not important, use snprintf(). It's easy to read the code.
221 int num_to_str(char *buf, int size, unsigned long long num)
223 char tmp[21]; /* Enough for 2^64 in decimal */
226 len = put_dec(tmp, num) - tmp;
230 for (idx = 0; idx < len; ++idx)
231 buf[idx] = tmp[len - idx - 1];
235 #define ZEROPAD 1 /* pad with zero */
236 #define SIGN 2 /* unsigned/signed long */
237 #define PLUS 4 /* show plus */
238 #define SPACE 8 /* space if plus */
239 #define LEFT 16 /* left justified */
240 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
241 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
244 FORMAT_TYPE_NONE, /* Just a string part */
246 FORMAT_TYPE_PRECISION,
250 FORMAT_TYPE_PERCENT_CHAR,
252 FORMAT_TYPE_LONG_LONG,
267 u8 type; /* format_type enum */
268 u8 flags; /* flags to number() */
269 u8 base; /* number base, 8, 10 or 16 only */
270 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
271 s16 field_width; /* width of output field */
272 s16 precision; /* # of digits/chars */
275 static noinline_for_stack
276 char *number(char *buf, char *end, unsigned long long num,
277 struct printf_spec spec)
279 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
280 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
285 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
287 bool is_zero = num == 0LL;
289 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
290 * produces same digits or (maybe lowercased) letters */
291 locase = (spec.flags & SMALL);
292 if (spec.flags & LEFT)
293 spec.flags &= ~ZEROPAD;
295 if (spec.flags & SIGN) {
296 if ((signed long long)num < 0) {
298 num = -(signed long long)num;
300 } else if (spec.flags & PLUS) {
303 } else if (spec.flags & SPACE) {
310 spec.field_width -= 2;
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 */
358 if (spec.base == 16 || !is_zero) {
363 if (spec.base == 16) {
365 *buf = ('X' | locase);
369 /* zero or space padding */
370 if (!(spec.flags & LEFT)) {
371 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
372 while (--spec.field_width >= 0) {
378 /* hmm even more zero padding? */
379 while (i <= --spec.precision) {
384 /* actual digits of result */
390 /* trailing space padding */
391 while (--spec.field_width >= 0) {
400 static noinline_for_stack
401 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
405 if ((unsigned long)s < PAGE_SIZE)
408 len = strnlen(s, spec.precision);
410 if (!(spec.flags & LEFT)) {
411 while (len < spec.field_width--) {
417 for (i = 0; i < len; ++i) {
422 while (len < spec.field_width--) {
431 static noinline_for_stack
432 char *symbol_string(char *buf, char *end, void *ptr,
433 struct printf_spec spec, char ext)
435 unsigned long value = (unsigned long) ptr;
436 #ifdef CONFIG_KALLSYMS
437 char sym[KSYM_SYMBOL_LEN];
439 sprint_backtrace(sym, value);
440 else if (ext != 'f' && ext != 's')
441 sprint_symbol(sym, value);
443 sprint_symbol_no_offset(sym, value);
445 return string(buf, end, sym, spec);
447 spec.field_width = 2 * sizeof(void *);
448 spec.flags |= SPECIAL | SMALL | ZEROPAD;
451 return number(buf, end, value, spec);
455 static noinline_for_stack
456 char *resource_string(char *buf, char *end, struct resource *res,
457 struct printf_spec spec, const char *fmt)
459 #ifndef IO_RSRC_PRINTK_SIZE
460 #define IO_RSRC_PRINTK_SIZE 6
463 #ifndef MEM_RSRC_PRINTK_SIZE
464 #define MEM_RSRC_PRINTK_SIZE 10
466 static const struct printf_spec io_spec = {
468 .field_width = IO_RSRC_PRINTK_SIZE,
470 .flags = SPECIAL | SMALL | ZEROPAD,
472 static const struct printf_spec mem_spec = {
474 .field_width = MEM_RSRC_PRINTK_SIZE,
476 .flags = SPECIAL | SMALL | ZEROPAD,
478 static const struct printf_spec bus_spec = {
482 .flags = SMALL | ZEROPAD,
484 static const struct printf_spec dec_spec = {
489 static const struct printf_spec str_spec = {
494 static const struct printf_spec flag_spec = {
497 .flags = SPECIAL | SMALL,
500 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
501 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
502 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
503 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
504 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
505 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
506 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
507 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
509 char *p = sym, *pend = sym + sizeof(sym);
510 int decode = (fmt[0] == 'R') ? 1 : 0;
511 const struct printf_spec *specp;
514 if (res->flags & IORESOURCE_IO) {
515 p = string(p, pend, "io ", str_spec);
517 } else if (res->flags & IORESOURCE_MEM) {
518 p = string(p, pend, "mem ", str_spec);
520 } else if (res->flags & IORESOURCE_IRQ) {
521 p = string(p, pend, "irq ", str_spec);
523 } else if (res->flags & IORESOURCE_DMA) {
524 p = string(p, pend, "dma ", str_spec);
526 } else if (res->flags & IORESOURCE_BUS) {
527 p = string(p, pend, "bus ", str_spec);
530 p = string(p, pend, "??? ", str_spec);
534 p = number(p, pend, res->start, *specp);
535 if (res->start != res->end) {
537 p = number(p, pend, res->end, *specp);
540 if (res->flags & IORESOURCE_MEM_64)
541 p = string(p, pend, " 64bit", str_spec);
542 if (res->flags & IORESOURCE_PREFETCH)
543 p = string(p, pend, " pref", str_spec);
544 if (res->flags & IORESOURCE_WINDOW)
545 p = string(p, pend, " window", str_spec);
546 if (res->flags & IORESOURCE_DISABLED)
547 p = string(p, pend, " disabled", str_spec);
549 p = string(p, pend, " flags ", str_spec);
550 p = number(p, pend, res->flags, flag_spec);
555 return string(buf, end, sym, spec);
558 static noinline_for_stack
559 char *mac_address_string(char *buf, char *end, u8 *addr,
560 struct printf_spec spec, const char *fmt)
562 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
567 if (fmt[1] == 'F') { /* FDDI canonical format */
573 for (i = 0; i < 6; i++) {
574 p = hex_byte_pack(p, addr[i]);
575 if (fmt[0] == 'M' && i != 5)
580 return string(buf, end, mac_addr, spec);
583 static noinline_for_stack
584 char *ip4_string(char *p, const u8 *addr, const char *fmt)
587 bool leading_zeros = (fmt[0] == 'i');
612 for (i = 0; i < 4; i++) {
613 char temp[3]; /* hold each IP quad in reverse order */
614 int digits = put_dec_trunc(temp, addr[index]) - temp;
621 /* reverse the digits in the quad */
633 static noinline_for_stack
634 char *ip6_compressed_string(char *p, const char *addr)
637 unsigned char zerolength[8];
642 bool needcolon = false;
646 memcpy(&in6, addr, sizeof(struct in6_addr));
648 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
650 memset(zerolength, 0, sizeof(zerolength));
657 /* find position of longest 0 run */
658 for (i = 0; i < range; i++) {
659 for (j = i; j < range; j++) {
660 if (in6.s6_addr16[j] != 0)
665 for (i = 0; i < range; i++) {
666 if (zerolength[i] > longest) {
667 longest = zerolength[i];
671 if (longest == 1) /* don't compress a single 0 */
675 for (i = 0; i < range; i++) {
677 if (needcolon || i == 0)
688 /* hex u16 without leading 0s */
689 word = ntohs(in6.s6_addr16[i]);
694 p = hex_byte_pack(p, hi);
696 *p++ = hex_asc_lo(hi);
697 p = hex_byte_pack(p, lo);
700 p = hex_byte_pack(p, lo);
702 *p++ = hex_asc_lo(lo);
709 p = ip4_string(p, &in6.s6_addr[12], "I4");
716 static noinline_for_stack
717 char *ip6_string(char *p, const char *addr, const char *fmt)
721 for (i = 0; i < 8; i++) {
722 p = hex_byte_pack(p, *addr++);
723 p = hex_byte_pack(p, *addr++);
724 if (fmt[0] == 'I' && i != 7)
732 static noinline_for_stack
733 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
734 struct printf_spec spec, const char *fmt)
736 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
738 if (fmt[0] == 'I' && fmt[2] == 'c')
739 ip6_compressed_string(ip6_addr, addr);
741 ip6_string(ip6_addr, addr, fmt);
743 return string(buf, end, ip6_addr, spec);
746 static noinline_for_stack
747 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
748 struct printf_spec spec, const char *fmt)
750 char ip4_addr[sizeof("255.255.255.255")];
752 ip4_string(ip4_addr, addr, fmt);
754 return string(buf, end, ip4_addr, spec);
757 static noinline_for_stack
758 char *uuid_string(char *buf, char *end, const u8 *addr,
759 struct printf_spec spec, const char *fmt)
761 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
764 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
765 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
766 const u8 *index = be;
771 uc = true; /* fall-through */
780 for (i = 0; i < 16; i++) {
781 p = hex_byte_pack(p, addr[index[i]]);
801 return string(buf, end, uuid, spec);
805 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
806 struct printf_spec spec)
808 spec.flags |= SPECIAL | SMALL | ZEROPAD;
809 if (spec.field_width == -1)
810 spec.field_width = 2 + 2 * sizeof(netdev_features_t);
813 return number(buf, end, *(const netdev_features_t *)addr, spec);
816 int kptr_restrict __read_mostly;
819 * Show a '%p' thing. A kernel extension is that the '%p' is followed
820 * by an extra set of alphanumeric characters that are extended format
823 * Right now we handle:
825 * - 'F' For symbolic function descriptor pointers with offset
826 * - 'f' For simple symbolic function names without offset
827 * - 'S' For symbolic direct pointers with offset
828 * - 's' For symbolic direct pointers without offset
829 * - 'B' For backtraced symbolic direct pointers with offset
830 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
831 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
832 * - 'M' For a 6-byte MAC address, it prints the address in the
833 * usual colon-separated hex notation
834 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
835 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
836 * with a dash-separated hex notation
837 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
838 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
839 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
840 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
841 * IPv6 omits the colons (01020304...0f)
842 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
843 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
844 * - 'I6c' for IPv6 addresses printed as specified by
845 * http://tools.ietf.org/html/rfc5952
846 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
847 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
848 * Options for %pU are:
849 * b big endian lower case hex (default)
850 * B big endian UPPER case hex
851 * l little endian lower case hex
852 * L little endian UPPER case hex
853 * big endian output byte order is:
854 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
855 * little endian output byte order is:
856 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
857 * - 'V' For a struct va_format which contains a format string * and va_list *,
858 * call vsnprintf(->format, *->va_list).
859 * Implements a "recursive vsnprintf".
860 * Do not use this feature without some mechanism to verify the
861 * correctness of the format string and va_list arguments.
862 * - 'K' For a kernel pointer that should be hidden from unprivileged users
863 * - 'NF' For a netdev_features_t
865 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
866 * function pointers are really function descriptors, which contain a
867 * pointer to the real address.
869 static noinline_for_stack
870 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
871 struct printf_spec spec)
873 int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
875 if (!ptr && *fmt != 'K') {
877 * Print (null) with the same width as a pointer so it makes
878 * tabular output look nice.
880 if (spec.field_width == -1)
881 spec.field_width = default_width;
882 return string(buf, end, "(null)", spec);
888 ptr = dereference_function_descriptor(ptr);
893 return symbol_string(buf, end, ptr, spec, *fmt);
896 return resource_string(buf, end, ptr, spec, fmt);
897 case 'M': /* Colon separated: 00:01:02:03:04:05 */
898 case 'm': /* Contiguous: 000102030405 */
899 /* [mM]F (FDDI, bit reversed) */
900 return mac_address_string(buf, end, ptr, spec, fmt);
901 case 'I': /* Formatted IP supported
903 * 6: 0001:0203:...:0708
904 * 6c: 1::708 or 1::1.2.3.4
906 case 'i': /* Contiguous:
912 return ip6_addr_string(buf, end, ptr, spec, fmt);
914 return ip4_addr_string(buf, end, ptr, spec, fmt);
918 return uuid_string(buf, end, ptr, spec, fmt);
923 va_copy(va, *((struct va_format *)ptr)->va);
924 buf += vsnprintf(buf, end > buf ? end - buf : 0,
925 ((struct va_format *)ptr)->fmt, va);
931 * %pK cannot be used in IRQ context because its test
932 * for CAP_SYSLOG would be meaningless.
934 if (in_irq() || in_serving_softirq() || in_nmi()) {
935 if (spec.field_width == -1)
936 spec.field_width = default_width;
937 return string(buf, end, "pK-error", spec);
939 if (!((kptr_restrict == 0) ||
940 (kptr_restrict == 1 &&
941 has_capability_noaudit(current, CAP_SYSLOG))))
947 return netdev_feature_string(buf, end, ptr, spec);
952 if (spec.field_width == -1) {
953 spec.field_width = default_width;
954 spec.flags |= ZEROPAD;
958 return number(buf, end, (unsigned long) ptr, spec);
962 * Helper function to decode printf style format.
963 * Each call decode a token from the format and return the
964 * number of characters read (or likely the delta where it wants
965 * to go on the next call).
966 * The decoded token is returned through the parameters
968 * 'h', 'l', or 'L' for integer fields
969 * 'z' support added 23/7/1999 S.H.
970 * 'z' changed to 'Z' --davidm 1/25/99
971 * 't' added for ptrdiff_t
973 * @fmt: the format string
974 * @type of the token returned
975 * @flags: various flags such as +, -, # tokens..
976 * @field_width: overwritten width
977 * @base: base of the number (octal, hex, ...)
978 * @precision: precision of a number
979 * @qualifier: qualifier of a number (long, size_t, ...)
981 static noinline_for_stack
982 int format_decode(const char *fmt, struct printf_spec *spec)
984 const char *start = fmt;
986 /* we finished early by reading the field width */
987 if (spec->type == FORMAT_TYPE_WIDTH) {
988 if (spec->field_width < 0) {
989 spec->field_width = -spec->field_width;
992 spec->type = FORMAT_TYPE_NONE;
996 /* we finished early by reading the precision */
997 if (spec->type == FORMAT_TYPE_PRECISION) {
998 if (spec->precision < 0)
1001 spec->type = FORMAT_TYPE_NONE;
1006 spec->type = FORMAT_TYPE_NONE;
1008 for (; *fmt ; ++fmt) {
1013 /* Return the current non-format string */
1014 if (fmt != start || !*fmt)
1020 while (1) { /* this also skips first '%' */
1026 case '-': spec->flags |= LEFT; break;
1027 case '+': spec->flags |= PLUS; break;
1028 case ' ': spec->flags |= SPACE; break;
1029 case '#': spec->flags |= SPECIAL; break;
1030 case '0': spec->flags |= ZEROPAD; break;
1031 default: found = false;
1038 /* get field width */
1039 spec->field_width = -1;
1042 spec->field_width = skip_atoi(&fmt);
1043 else if (*fmt == '*') {
1044 /* it's the next argument */
1045 spec->type = FORMAT_TYPE_WIDTH;
1046 return ++fmt - start;
1050 /* get the precision */
1051 spec->precision = -1;
1054 if (isdigit(*fmt)) {
1055 spec->precision = skip_atoi(&fmt);
1056 if (spec->precision < 0)
1057 spec->precision = 0;
1058 } else if (*fmt == '*') {
1059 /* it's the next argument */
1060 spec->type = FORMAT_TYPE_PRECISION;
1061 return ++fmt - start;
1066 /* get the conversion qualifier */
1067 spec->qualifier = -1;
1068 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1069 _tolower(*fmt) == 'z' || *fmt == 't') {
1070 spec->qualifier = *fmt++;
1071 if (unlikely(spec->qualifier == *fmt)) {
1072 if (spec->qualifier == 'l') {
1073 spec->qualifier = 'L';
1075 } else if (spec->qualifier == 'h') {
1076 spec->qualifier = 'H';
1086 spec->type = FORMAT_TYPE_CHAR;
1087 return ++fmt - start;
1090 spec->type = FORMAT_TYPE_STR;
1091 return ++fmt - start;
1094 spec->type = FORMAT_TYPE_PTR;
1099 spec->type = FORMAT_TYPE_NRCHARS;
1100 return ++fmt - start;
1103 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1104 return ++fmt - start;
1106 /* integer number formats - set up the flags and "break" */
1112 spec->flags |= SMALL;
1120 spec->flags |= SIGN;
1125 spec->type = FORMAT_TYPE_INVALID;
1129 if (spec->qualifier == 'L')
1130 spec->type = FORMAT_TYPE_LONG_LONG;
1131 else if (spec->qualifier == 'l') {
1132 if (spec->flags & SIGN)
1133 spec->type = FORMAT_TYPE_LONG;
1135 spec->type = FORMAT_TYPE_ULONG;
1136 } else if (_tolower(spec->qualifier) == 'z') {
1137 spec->type = FORMAT_TYPE_SIZE_T;
1138 } else if (spec->qualifier == 't') {
1139 spec->type = FORMAT_TYPE_PTRDIFF;
1140 } else if (spec->qualifier == 'H') {
1141 if (spec->flags & SIGN)
1142 spec->type = FORMAT_TYPE_BYTE;
1144 spec->type = FORMAT_TYPE_UBYTE;
1145 } else if (spec->qualifier == 'h') {
1146 if (spec->flags & SIGN)
1147 spec->type = FORMAT_TYPE_SHORT;
1149 spec->type = FORMAT_TYPE_USHORT;
1151 if (spec->flags & SIGN)
1152 spec->type = FORMAT_TYPE_INT;
1154 spec->type = FORMAT_TYPE_UINT;
1157 return ++fmt - start;
1161 * vsnprintf - Format a string and place it in a buffer
1162 * @buf: The buffer to place the result into
1163 * @size: The size of the buffer, including the trailing null space
1164 * @fmt: The format string to use
1165 * @args: Arguments for the format string
1167 * This function follows C99 vsnprintf, but has some extensions:
1168 * %pS output the name of a text symbol with offset
1169 * %ps output the name of a text symbol without offset
1170 * %pF output the name of a function pointer with its offset
1171 * %pf output the name of a function pointer without its offset
1172 * %pB output the name of a backtrace symbol with its offset
1173 * %pR output the address range in a struct resource with decoded flags
1174 * %pr output the address range in a struct resource with raw flags
1175 * %pM output a 6-byte MAC address with colons
1176 * %pm output a 6-byte MAC address without colons
1177 * %pI4 print an IPv4 address without leading zeros
1178 * %pi4 print an IPv4 address with leading zeros
1179 * %pI6 print an IPv6 address with colons
1180 * %pi6 print an IPv6 address without colons
1181 * %pI6c print an IPv6 address as specified by RFC 5952
1182 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1186 * The return value is the number of characters which would
1187 * be generated for the given input, excluding the trailing
1188 * '\0', as per ISO C99. If you want to have the exact
1189 * number of characters written into @buf as return value
1190 * (not including the trailing '\0'), use vscnprintf(). If the
1191 * return is greater than or equal to @size, the resulting
1192 * string is truncated.
1194 * If you're not already dealing with a va_list consider using snprintf().
1196 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1198 unsigned long long num;
1200 struct printf_spec spec = {0};
1202 /* Reject out-of-range values early. Large positive sizes are
1203 used for unknown buffer sizes. */
1204 if (WARN_ON_ONCE((int) size < 0))
1210 /* Make sure end is always >= buf */
1217 const char *old_fmt = fmt;
1218 int read = format_decode(fmt, &spec);
1222 switch (spec.type) {
1223 case FORMAT_TYPE_NONE: {
1226 if (copy > end - str)
1228 memcpy(str, old_fmt, copy);
1234 case FORMAT_TYPE_WIDTH:
1235 spec.field_width = va_arg(args, int);
1238 case FORMAT_TYPE_PRECISION:
1239 spec.precision = va_arg(args, int);
1242 case FORMAT_TYPE_CHAR: {
1245 if (!(spec.flags & LEFT)) {
1246 while (--spec.field_width > 0) {
1253 c = (unsigned char) va_arg(args, int);
1257 while (--spec.field_width > 0) {
1265 case FORMAT_TYPE_STR:
1266 str = string(str, end, va_arg(args, char *), spec);
1269 case FORMAT_TYPE_PTR:
1270 str = pointer(fmt+1, str, end, va_arg(args, void *),
1272 while (isalnum(*fmt))
1276 case FORMAT_TYPE_PERCENT_CHAR:
1282 case FORMAT_TYPE_INVALID:
1288 case FORMAT_TYPE_NRCHARS: {
1289 u8 qualifier = spec.qualifier;
1291 if (qualifier == 'l') {
1292 long *ip = va_arg(args, long *);
1294 } else if (_tolower(qualifier) == 'z') {
1295 size_t *ip = va_arg(args, size_t *);
1298 int *ip = va_arg(args, int *);
1305 switch (spec.type) {
1306 case FORMAT_TYPE_LONG_LONG:
1307 num = va_arg(args, long long);
1309 case FORMAT_TYPE_ULONG:
1310 num = va_arg(args, unsigned long);
1312 case FORMAT_TYPE_LONG:
1313 num = va_arg(args, long);
1315 case FORMAT_TYPE_SIZE_T:
1316 num = va_arg(args, size_t);
1318 case FORMAT_TYPE_PTRDIFF:
1319 num = va_arg(args, ptrdiff_t);
1321 case FORMAT_TYPE_UBYTE:
1322 num = (unsigned char) va_arg(args, int);
1324 case FORMAT_TYPE_BYTE:
1325 num = (signed char) va_arg(args, int);
1327 case FORMAT_TYPE_USHORT:
1328 num = (unsigned short) va_arg(args, int);
1330 case FORMAT_TYPE_SHORT:
1331 num = (short) va_arg(args, int);
1333 case FORMAT_TYPE_INT:
1334 num = (int) va_arg(args, int);
1337 num = va_arg(args, unsigned int);
1340 str = number(str, end, num, spec);
1351 /* the trailing null byte doesn't count towards the total */
1355 EXPORT_SYMBOL(vsnprintf);
1358 * vscnprintf - 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 * @args: Arguments for the format string
1364 * The return value is the number of characters which have been written into
1365 * the @buf not including the trailing '\0'. If @size is == 0 the function
1368 * If you're not already dealing with a va_list consider using scnprintf().
1370 * See the vsnprintf() documentation for format string extensions over C99.
1372 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1376 i = vsnprintf(buf, size, fmt, args);
1378 if (likely(i < size))
1384 EXPORT_SYMBOL(vscnprintf);
1387 * snprintf - Format a string and place it in a buffer
1388 * @buf: The buffer to place the result into
1389 * @size: The size of the buffer, including the trailing null space
1390 * @fmt: The format string to use
1391 * @...: Arguments for the format string
1393 * The return value is the number of characters which would be
1394 * generated for the given input, excluding the trailing null,
1395 * as per ISO C99. If the return is greater than or equal to
1396 * @size, the resulting string is truncated.
1398 * See the vsnprintf() documentation for format string extensions over C99.
1400 int snprintf(char *buf, size_t size, const char *fmt, ...)
1405 va_start(args, fmt);
1406 i = vsnprintf(buf, size, fmt, args);
1411 EXPORT_SYMBOL(snprintf);
1414 * scnprintf - Format a string and place it in a buffer
1415 * @buf: The buffer to place the result into
1416 * @size: The size of the buffer, including the trailing null space
1417 * @fmt: The format string to use
1418 * @...: Arguments for the format string
1420 * The return value is the number of characters written into @buf not including
1421 * the trailing '\0'. If @size is == 0 the function returns 0.
1424 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1429 va_start(args, fmt);
1430 i = vscnprintf(buf, size, fmt, args);
1435 EXPORT_SYMBOL(scnprintf);
1438 * vsprintf - Format a string and place it in a buffer
1439 * @buf: The buffer to place the result into
1440 * @fmt: The format string to use
1441 * @args: Arguments for the format string
1443 * The function returns the number of characters written
1444 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1447 * If you're not already dealing with a va_list consider using sprintf().
1449 * See the vsnprintf() documentation for format string extensions over C99.
1451 int vsprintf(char *buf, const char *fmt, va_list args)
1453 return vsnprintf(buf, INT_MAX, fmt, args);
1455 EXPORT_SYMBOL(vsprintf);
1458 * sprintf - Format a string and place it in a buffer
1459 * @buf: The buffer to place the result into
1460 * @fmt: The format string to use
1461 * @...: Arguments for the format string
1463 * The function returns the number of characters written
1464 * into @buf. Use snprintf() or scnprintf() in order to avoid
1467 * See the vsnprintf() documentation for format string extensions over C99.
1469 int sprintf(char *buf, const char *fmt, ...)
1474 va_start(args, fmt);
1475 i = vsnprintf(buf, INT_MAX, fmt, args);
1480 EXPORT_SYMBOL(sprintf);
1482 #ifdef CONFIG_BINARY_PRINTF
1485 * vbin_printf() - VA arguments to binary data
1486 * bstr_printf() - Binary data to text string
1490 * vbin_printf - Parse a format string and place args' binary value in a buffer
1491 * @bin_buf: The buffer to place args' binary value
1492 * @size: The size of the buffer(by words(32bits), not characters)
1493 * @fmt: The format string to use
1494 * @args: Arguments for the format string
1496 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1499 * The return value is the number of words(32bits) which would be generated for
1503 * If the return value is greater than @size, the resulting bin_buf is NOT
1504 * valid for bstr_printf().
1506 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1508 struct printf_spec spec = {0};
1511 str = (char *)bin_buf;
1512 end = (char *)(bin_buf + size);
1514 #define save_arg(type) \
1516 if (sizeof(type) == 8) { \
1517 unsigned long long value; \
1518 str = PTR_ALIGN(str, sizeof(u32)); \
1519 value = va_arg(args, unsigned long long); \
1520 if (str + sizeof(type) <= end) { \
1521 *(u32 *)str = *(u32 *)&value; \
1522 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1525 unsigned long value; \
1526 str = PTR_ALIGN(str, sizeof(type)); \
1527 value = va_arg(args, int); \
1528 if (str + sizeof(type) <= end) \
1529 *(typeof(type) *)str = (type)value; \
1531 str += sizeof(type); \
1535 int read = format_decode(fmt, &spec);
1539 switch (spec.type) {
1540 case FORMAT_TYPE_NONE:
1541 case FORMAT_TYPE_INVALID:
1542 case FORMAT_TYPE_PERCENT_CHAR:
1545 case FORMAT_TYPE_WIDTH:
1546 case FORMAT_TYPE_PRECISION:
1550 case FORMAT_TYPE_CHAR:
1554 case FORMAT_TYPE_STR: {
1555 const char *save_str = va_arg(args, char *);
1558 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1559 || (unsigned long)save_str < PAGE_SIZE)
1560 save_str = "(null)";
1561 len = strlen(save_str) + 1;
1562 if (str + len < end)
1563 memcpy(str, save_str, len);
1568 case FORMAT_TYPE_PTR:
1570 /* skip all alphanumeric pointer suffixes */
1571 while (isalnum(*fmt))
1575 case FORMAT_TYPE_NRCHARS: {
1576 /* skip %n 's argument */
1577 u8 qualifier = spec.qualifier;
1579 if (qualifier == 'l')
1580 skip_arg = va_arg(args, long *);
1581 else if (_tolower(qualifier) == 'z')
1582 skip_arg = va_arg(args, size_t *);
1584 skip_arg = va_arg(args, int *);
1589 switch (spec.type) {
1591 case FORMAT_TYPE_LONG_LONG:
1592 save_arg(long long);
1594 case FORMAT_TYPE_ULONG:
1595 case FORMAT_TYPE_LONG:
1596 save_arg(unsigned long);
1598 case FORMAT_TYPE_SIZE_T:
1601 case FORMAT_TYPE_PTRDIFF:
1602 save_arg(ptrdiff_t);
1604 case FORMAT_TYPE_UBYTE:
1605 case FORMAT_TYPE_BYTE:
1608 case FORMAT_TYPE_USHORT:
1609 case FORMAT_TYPE_SHORT:
1618 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1621 EXPORT_SYMBOL_GPL(vbin_printf);
1624 * bstr_printf - Format a string from binary arguments and place it in a buffer
1625 * @buf: The buffer to place the result into
1626 * @size: The size of the buffer, including the trailing null space
1627 * @fmt: The format string to use
1628 * @bin_buf: Binary arguments for the format string
1630 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1631 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1632 * a binary buffer that generated by vbin_printf.
1634 * The format follows C99 vsnprintf, but has some extensions:
1635 * see vsnprintf comment for details.
1637 * The return value is the number of characters which would
1638 * be generated for the given input, excluding the trailing
1639 * '\0', as per ISO C99. If you want to have the exact
1640 * number of characters written into @buf as return value
1641 * (not including the trailing '\0'), use vscnprintf(). If the
1642 * return is greater than or equal to @size, the resulting
1643 * string is truncated.
1645 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1647 struct printf_spec spec = {0};
1649 const char *args = (const char *)bin_buf;
1651 if (WARN_ON_ONCE((int) size < 0))
1657 #define get_arg(type) \
1659 typeof(type) value; \
1660 if (sizeof(type) == 8) { \
1661 args = PTR_ALIGN(args, sizeof(u32)); \
1662 *(u32 *)&value = *(u32 *)args; \
1663 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1665 args = PTR_ALIGN(args, sizeof(type)); \
1666 value = *(typeof(type) *)args; \
1668 args += sizeof(type); \
1672 /* Make sure end is always >= buf */
1679 const char *old_fmt = fmt;
1680 int read = format_decode(fmt, &spec);
1684 switch (spec.type) {
1685 case FORMAT_TYPE_NONE: {
1688 if (copy > end - str)
1690 memcpy(str, old_fmt, copy);
1696 case FORMAT_TYPE_WIDTH:
1697 spec.field_width = get_arg(int);
1700 case FORMAT_TYPE_PRECISION:
1701 spec.precision = get_arg(int);
1704 case FORMAT_TYPE_CHAR: {
1707 if (!(spec.flags & LEFT)) {
1708 while (--spec.field_width > 0) {
1714 c = (unsigned char) get_arg(char);
1718 while (--spec.field_width > 0) {
1726 case FORMAT_TYPE_STR: {
1727 const char *str_arg = args;
1728 args += strlen(str_arg) + 1;
1729 str = string(str, end, (char *)str_arg, spec);
1733 case FORMAT_TYPE_PTR:
1734 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1735 while (isalnum(*fmt))
1739 case FORMAT_TYPE_PERCENT_CHAR:
1740 case FORMAT_TYPE_INVALID:
1746 case FORMAT_TYPE_NRCHARS:
1751 unsigned long long num;
1753 switch (spec.type) {
1755 case FORMAT_TYPE_LONG_LONG:
1756 num = get_arg(long long);
1758 case FORMAT_TYPE_ULONG:
1759 case FORMAT_TYPE_LONG:
1760 num = get_arg(unsigned long);
1762 case FORMAT_TYPE_SIZE_T:
1763 num = get_arg(size_t);
1765 case FORMAT_TYPE_PTRDIFF:
1766 num = get_arg(ptrdiff_t);
1768 case FORMAT_TYPE_UBYTE:
1769 num = get_arg(unsigned char);
1771 case FORMAT_TYPE_BYTE:
1772 num = get_arg(signed char);
1774 case FORMAT_TYPE_USHORT:
1775 num = get_arg(unsigned short);
1777 case FORMAT_TYPE_SHORT:
1778 num = get_arg(short);
1780 case FORMAT_TYPE_UINT:
1781 num = get_arg(unsigned int);
1787 str = number(str, end, num, spec);
1789 } /* switch(spec.type) */
1801 /* the trailing null byte doesn't count towards the total */
1804 EXPORT_SYMBOL_GPL(bstr_printf);
1807 * bprintf - Parse a format string and place args' binary value in a buffer
1808 * @bin_buf: The buffer to place args' binary value
1809 * @size: The size of the buffer(by words(32bits), not characters)
1810 * @fmt: The format string to use
1811 * @...: Arguments for the format string
1813 * The function returns the number of words(u32) written
1816 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1821 va_start(args, fmt);
1822 ret = vbin_printf(bin_buf, size, fmt, args);
1827 EXPORT_SYMBOL_GPL(bprintf);
1829 #endif /* CONFIG_BINARY_PRINTF */
1832 * vsscanf - Unformat a buffer into a list of arguments
1833 * @buf: input buffer
1834 * @fmt: format of buffer
1837 int vsscanf(const char *buf, const char *fmt, va_list args)
1839 const char *str = buf;
1848 while (*fmt && *str) {
1849 /* skip any white space in format */
1850 /* white space in format matchs any amount of
1851 * white space, including none, in the input.
1853 if (isspace(*fmt)) {
1854 fmt = skip_spaces(++fmt);
1855 str = skip_spaces(str);
1858 /* anything that is not a conversion must match exactly */
1859 if (*fmt != '%' && *fmt) {
1860 if (*fmt++ != *str++)
1869 /* skip this conversion.
1870 * advance both strings to next white space
1873 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1875 while (!isspace(*str) && *str)
1880 /* get field width */
1883 field_width = skip_atoi(&fmt);
1885 /* get conversion qualifier */
1887 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1888 _tolower(*fmt) == 'z') {
1890 if (unlikely(qualifier == *fmt)) {
1891 if (qualifier == 'h') {
1894 } else if (qualifier == 'l') {
1910 char *s = (char *)va_arg(args, char*);
1911 if (field_width == -1)
1915 } while (--field_width > 0 && *str);
1921 char *s = (char *)va_arg(args, char *);
1922 if (field_width == -1)
1923 field_width = SHRT_MAX;
1924 /* first, skip leading white space in buffer */
1925 str = skip_spaces(str);
1927 /* now copy until next white space */
1928 while (*str && !isspace(*str) && field_width--)
1935 /* return number of characters read so far */
1937 int *i = (int *)va_arg(args, int*);
1955 /* looking for '%' in str */
1960 /* invalid format; stop here */
1964 /* have some sort of integer conversion.
1965 * first, skip white space in buffer.
1967 str = skip_spaces(str);
1970 if (is_sign && digit == '-')
1974 || (base == 16 && !isxdigit(digit))
1975 || (base == 10 && !isdigit(digit))
1976 || (base == 8 && (!isdigit(digit) || digit > '7'))
1977 || (base == 0 && !isdigit(digit)))
1980 switch (qualifier) {
1981 case 'H': /* that's 'hh' in format */
1983 signed char *s = (signed char *)va_arg(args, signed char *);
1984 *s = (signed char)simple_strtol(str, &next, base);
1986 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1987 *s = (unsigned char)simple_strtoul(str, &next, base);
1992 short *s = (short *)va_arg(args, short *);
1993 *s = (short)simple_strtol(str, &next, base);
1995 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1996 *s = (unsigned short)simple_strtoul(str, &next, base);
2001 long *l = (long *)va_arg(args, long *);
2002 *l = simple_strtol(str, &next, base);
2004 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2005 *l = simple_strtoul(str, &next, base);
2010 long long *l = (long long *)va_arg(args, long long *);
2011 *l = simple_strtoll(str, &next, base);
2013 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2014 *l = simple_strtoull(str, &next, base);
2020 size_t *s = (size_t *)va_arg(args, size_t *);
2021 *s = (size_t)simple_strtoul(str, &next, base);
2026 int *i = (int *)va_arg(args, int *);
2027 *i = (int)simple_strtol(str, &next, base);
2029 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2030 *i = (unsigned int)simple_strtoul(str, &next, base);
2042 * Now we've come all the way through so either the input string or the
2043 * format ended. In the former case, there can be a %n at the current
2044 * position in the format that needs to be filled.
2046 if (*fmt == '%' && *(fmt + 1) == 'n') {
2047 int *p = (int *)va_arg(args, int *);
2053 EXPORT_SYMBOL(vsscanf);
2056 * sscanf - Unformat a buffer into a list of arguments
2057 * @buf: input buffer
2058 * @fmt: formatting of buffer
2059 * @...: resulting arguments
2061 int sscanf(const char *buf, const char *fmt, ...)
2066 va_start(args, fmt);
2067 i = vsscanf(buf, fmt, args);
2072 EXPORT_SYMBOL(sscanf);