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);
123 * strict_strtoul - convert a string to an unsigned long strictly
124 * @cp: The string to be converted
125 * @base: The number base to use
126 * @res: The converted result value
128 * strict_strtoul converts a string to an unsigned long only if the
129 * string is really an unsigned long string, any string containing
130 * any invalid char at the tail will be rejected and -EINVAL is returned,
131 * only a newline char at the tail is acceptible because people generally
132 * change a module parameter in the following way:
134 * echo 1024 > /sys/module/e1000/parameters/copybreak
136 * echo will append a newline to the tail.
138 * It returns 0 if conversion is successful and *res is set to the converted
139 * value, otherwise it returns -EINVAL and *res is set to 0.
141 * simple_strtoul just ignores the successive invalid characters and
142 * return the converted value of prefix part of the string.
144 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
155 val = simple_strtoul(cp, &tail, base);
159 if ((*tail == '\0') ||
160 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
167 EXPORT_SYMBOL(strict_strtoul);
170 * strict_strtol - convert a string to a long strictly
171 * @cp: The string to be converted
172 * @base: The number base to use
173 * @res: The converted result value
175 * strict_strtol is similiar to strict_strtoul, but it allows the first
176 * character of a string is '-'.
178 * It returns 0 if conversion is successful and *res is set to the converted
179 * value, otherwise it returns -EINVAL and *res is set to 0.
181 int strict_strtol(const char *cp, unsigned int base, long *res)
185 ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
189 ret = strict_strtoul(cp, base, (unsigned long *)res);
194 EXPORT_SYMBOL(strict_strtol);
197 * strict_strtoull - convert a string to an unsigned long long strictly
198 * @cp: The string to be converted
199 * @base: The number base to use
200 * @res: The converted result value
202 * strict_strtoull converts a string to an unsigned long long only if the
203 * string is really an unsigned long long string, any string containing
204 * any invalid char at the tail will be rejected and -EINVAL is returned,
205 * only a newline char at the tail is acceptible because people generally
206 * change a module parameter in the following way:
208 * echo 1024 > /sys/module/e1000/parameters/copybreak
210 * echo will append a newline to the tail of the string.
212 * It returns 0 if conversion is successful and *res is set to the converted
213 * value, otherwise it returns -EINVAL and *res is set to 0.
215 * simple_strtoull just ignores the successive invalid characters and
216 * return the converted value of prefix part of the string.
218 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
221 unsigned long long val;
229 val = simple_strtoull(cp, &tail, base);
232 if ((*tail == '\0') ||
233 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
240 EXPORT_SYMBOL(strict_strtoull);
243 * strict_strtoll - convert a string to a long long strictly
244 * @cp: The string to be converted
245 * @base: The number base to use
246 * @res: The converted result value
248 * strict_strtoll is similiar to strict_strtoull, but it allows the first
249 * character of a string is '-'.
251 * It returns 0 if conversion is successful and *res is set to the converted
252 * value, otherwise it returns -EINVAL and *res is set to 0.
254 int strict_strtoll(const char *cp, unsigned int base, long long *res)
258 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
262 ret = strict_strtoull(cp, base, (unsigned long long *)res);
267 EXPORT_SYMBOL(strict_strtoll);
269 static int skip_atoi(const char **s)
274 i = i*10 + *((*s)++) - '0';
279 /* Decimal conversion is by far the most typical, and is used
280 * for /proc and /sys data. This directly impacts e.g. top performance
281 * with many processes running. We optimize it for speed
283 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
284 * (with permission from the author, Douglas W. Jones). */
286 /* Formats correctly any integer in [0,99999].
287 * Outputs from one to five digits depending on input.
288 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
289 static char *put_dec_trunc(char *buf, unsigned q)
291 unsigned d3, d2, d1, d0;
296 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
297 q = (d0 * 0xcd) >> 11;
299 *buf++ = d0 + '0'; /* least significant digit */
300 d1 = q + 9*d3 + 5*d2 + d1;
302 q = (d1 * 0xcd) >> 11;
304 *buf++ = d1 + '0'; /* next digit */
307 if ((d2 != 0) || (d3 != 0)) {
310 *buf++ = d2 + '0'; /* next digit */
314 q = (d3 * 0xcd) >> 11;
316 *buf++ = d3 + '0'; /* next digit */
318 *buf++ = q + '0'; /* most sign. digit */
325 /* Same with if's removed. Always emits five digits */
326 static char *put_dec_full(char *buf, unsigned q)
328 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
329 /* but anyway, gcc produces better code with full-sized ints */
330 unsigned d3, d2, d1, d0;
336 * Possible ways to approx. divide by 10
337 * gcc -O2 replaces multiply with shifts and adds
338 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
339 * (x * 0x67) >> 10: 1100111
340 * (x * 0x34) >> 9: 110100 - same
341 * (x * 0x1a) >> 8: 11010 - same
342 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
344 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
345 q = (d0 * 0xcd) >> 11;
348 d1 = q + 9*d3 + 5*d2 + d1;
349 q = (d1 * 0xcd) >> 11;
359 q = (d3 * 0xcd) >> 11; /* - shorter code */
360 /* q = (d3 * 0x67) >> 10; - would also work */
367 /* No inlining helps gcc to use registers better */
368 static noinline char *put_dec(char *buf, unsigned long long num)
373 return put_dec_trunc(buf, num);
374 rem = do_div(num, 100000);
375 buf = put_dec_full(buf, rem);
379 #define ZEROPAD 1 /* pad with zero */
380 #define SIGN 2 /* unsigned/signed long */
381 #define PLUS 4 /* show plus */
382 #define SPACE 8 /* space if plus */
383 #define LEFT 16 /* left justified */
384 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
385 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
388 FORMAT_TYPE_NONE, /* Just a string part */
390 FORMAT_TYPE_PRECISION,
394 FORMAT_TYPE_PERCENT_CHAR,
396 FORMAT_TYPE_LONG_LONG,
412 s16 field_width; /* width of output field */
413 u8 flags; /* flags to number() */
415 s8 precision; /* # of digits/chars */
419 static char *number(char *buf, char *end, unsigned long long num,
420 struct printf_spec spec)
422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
431 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
432 * produces same digits or (maybe lowercased) letters */
433 locase = (spec.flags & SMALL);
434 if (spec.flags & LEFT)
435 spec.flags &= ~ZEROPAD;
437 if (spec.flags & SIGN) {
438 if ((signed long long)num < 0) {
440 num = -(signed long long)num;
442 } else if (spec.flags & PLUS) {
445 } else if (spec.flags & SPACE) {
456 /* generate full string in tmp[], in reverse order */
460 /* Generic code, for any base:
462 tmp[i++] = (digits[do_div(num,base)] | locase);
465 else if (spec.base != 10) { /* 8 or 16 */
466 int mask = spec.base - 1;
472 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
475 } else { /* base 10 */
476 i = put_dec(tmp, num) - tmp;
479 /* printing 100 using %2d gives "100", not "00" */
480 if (i > spec.precision)
482 /* leading space padding */
483 spec.field_width -= spec.precision;
484 if (!(spec.flags & (ZEROPAD+LEFT))) {
485 while (--spec.field_width >= 0) {
497 /* "0x" / "0" prefix */
502 if (spec.base == 16) {
504 *buf = ('X' | locase);
508 /* zero or space padding */
509 if (!(spec.flags & LEFT)) {
510 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
511 while (--spec.field_width >= 0) {
517 /* hmm even more zero padding? */
518 while (i <= --spec.precision) {
523 /* actual digits of result */
529 /* trailing space padding */
530 while (--spec.field_width >= 0) {
539 static char *string(char *buf, char *end, const char *s, struct printf_spec spec)
543 if ((unsigned long)s < PAGE_SIZE)
546 len = strnlen(s, spec.precision);
548 if (!(spec.flags & LEFT)) {
549 while (len < spec.field_width--) {
555 for (i = 0; i < len; ++i) {
560 while (len < spec.field_width--) {
569 static char *symbol_string(char *buf, char *end, void *ptr,
570 struct printf_spec spec, char ext)
572 unsigned long value = (unsigned long) ptr;
573 #ifdef CONFIG_KALLSYMS
574 char sym[KSYM_SYMBOL_LEN];
575 if (ext != 'f' && ext != 's')
576 sprint_symbol(sym, value);
578 kallsyms_lookup(value, NULL, NULL, NULL, sym);
580 return string(buf, end, sym, spec);
582 spec.field_width = 2 * sizeof(void *);
583 spec.flags |= SPECIAL | SMALL | ZEROPAD;
586 return number(buf, end, value, spec);
590 static char *resource_string(char *buf, char *end, struct resource *res,
591 struct printf_spec spec, const char *fmt)
593 #ifndef IO_RSRC_PRINTK_SIZE
594 #define IO_RSRC_PRINTK_SIZE 6
597 #ifndef MEM_RSRC_PRINTK_SIZE
598 #define MEM_RSRC_PRINTK_SIZE 10
600 static const struct printf_spec io_spec = {
602 .field_width = IO_RSRC_PRINTK_SIZE,
604 .flags = SPECIAL | SMALL | ZEROPAD,
606 static const struct printf_spec mem_spec = {
608 .field_width = MEM_RSRC_PRINTK_SIZE,
610 .flags = SPECIAL | SMALL | ZEROPAD,
612 static const struct printf_spec dec_spec = {
617 static const struct printf_spec str_spec = {
622 static const struct printf_spec flag_spec = {
625 .flags = SPECIAL | SMALL,
628 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
629 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
630 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
631 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
632 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref disabled]")
633 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
634 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
635 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
637 char *p = sym, *pend = sym + sizeof(sym);
638 int decode = (fmt[0] == 'R') ? 1 : 0;
639 const struct printf_spec *specp;
642 if (res->flags & IORESOURCE_IO) {
643 p = string(p, pend, "io ", str_spec);
645 } else if (res->flags & IORESOURCE_MEM) {
646 p = string(p, pend, "mem ", str_spec);
648 } else if (res->flags & IORESOURCE_IRQ) {
649 p = string(p, pend, "irq ", str_spec);
651 } else if (res->flags & IORESOURCE_DMA) {
652 p = string(p, pend, "dma ", str_spec);
655 p = string(p, pend, "??? ", str_spec);
659 p = number(p, pend, res->start, *specp);
660 if (res->start != res->end) {
662 p = number(p, pend, res->end, *specp);
665 if (res->flags & IORESOURCE_MEM_64)
666 p = string(p, pend, " 64bit", str_spec);
667 if (res->flags & IORESOURCE_PREFETCH)
668 p = string(p, pend, " pref", str_spec);
669 if (res->flags & IORESOURCE_DISABLED)
670 p = string(p, pend, " disabled", str_spec);
672 p = string(p, pend, " flags ", str_spec);
673 p = number(p, pend, res->flags, flag_spec);
678 return string(buf, end, sym, spec);
681 static char *mac_address_string(char *buf, char *end, u8 *addr,
682 struct printf_spec spec, const char *fmt)
684 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
689 if (fmt[1] == 'F') { /* FDDI canonical format */
695 for (i = 0; i < 6; i++) {
696 p = pack_hex_byte(p, addr[i]);
697 if (fmt[0] == 'M' && i != 5)
702 return string(buf, end, mac_addr, spec);
705 static char *ip4_string(char *p, const u8 *addr, const char *fmt)
708 bool leading_zeros = (fmt[0] == 'i');
733 for (i = 0; i < 4; i++) {
734 char temp[3]; /* hold each IP quad in reverse order */
735 int digits = put_dec_trunc(temp, addr[index]) - temp;
742 /* reverse the digits in the quad */
754 static char *ip6_compressed_string(char *p, const char *addr)
757 unsigned char zerolength[8];
762 bool needcolon = false;
766 memcpy(&in6, addr, sizeof(struct in6_addr));
768 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
770 memset(zerolength, 0, sizeof(zerolength));
777 /* find position of longest 0 run */
778 for (i = 0; i < range; i++) {
779 for (j = i; j < range; j++) {
780 if (in6.s6_addr16[j] != 0)
785 for (i = 0; i < range; i++) {
786 if (zerolength[i] > longest) {
787 longest = zerolength[i];
793 for (i = 0; i < range; i++) {
795 if (needcolon || i == 0)
806 /* hex u16 without leading 0s */
807 word = ntohs(in6.s6_addr16[i]);
812 p = pack_hex_byte(p, hi);
814 *p++ = hex_asc_lo(hi);
815 p = pack_hex_byte(p, lo);
818 p = pack_hex_byte(p, lo);
820 *p++ = hex_asc_lo(lo);
827 p = ip4_string(p, &in6.s6_addr[12], "I4");
834 static char *ip6_string(char *p, const char *addr, const char *fmt)
838 for (i = 0; i < 8; i++) {
839 p = pack_hex_byte(p, *addr++);
840 p = pack_hex_byte(p, *addr++);
841 if (fmt[0] == 'I' && i != 7)
849 static char *ip6_addr_string(char *buf, char *end, const u8 *addr,
850 struct printf_spec spec, const char *fmt)
852 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
854 if (fmt[0] == 'I' && fmt[2] == 'c')
855 ip6_compressed_string(ip6_addr, addr);
857 ip6_string(ip6_addr, addr, fmt);
859 return string(buf, end, ip6_addr, spec);
862 static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
863 struct printf_spec spec, const char *fmt)
865 char ip4_addr[sizeof("255.255.255.255")];
867 ip4_string(ip4_addr, addr, fmt);
869 return string(buf, end, ip4_addr, spec);
872 static char *uuid_string(char *buf, char *end, const u8 *addr,
873 struct printf_spec spec, const char *fmt)
875 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
878 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
879 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
880 const u8 *index = be;
885 uc = true; /* fall-through */
894 for (i = 0; i < 16; i++) {
895 p = pack_hex_byte(p, addr[index[i]]);
915 return string(buf, end, uuid, spec);
919 * Show a '%p' thing. A kernel extension is that the '%p' is followed
920 * by an extra set of alphanumeric characters that are extended format
923 * Right now we handle:
925 * - 'F' For symbolic function descriptor pointers with offset
926 * - 'f' For simple symbolic function names without offset
927 * - 'S' For symbolic direct pointers with offset
928 * - 's' For symbolic direct pointers without offset
929 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
930 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
931 * - 'M' For a 6-byte MAC address, it prints the address in the
932 * usual colon-separated hex notation
933 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
934 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
935 * with a dash-separated hex notation
936 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
937 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
938 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
939 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
940 * IPv6 omits the colons (01020304...0f)
941 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
942 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
943 * - 'I6c' for IPv6 addresses printed as specified by
944 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
945 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
946 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
947 * Options for %pU are:
948 * b big endian lower case hex (default)
949 * B big endian UPPER case hex
950 * l little endian lower case hex
951 * L little endian UPPER case hex
952 * big endian output byte order is:
953 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
954 * little endian output byte order is:
955 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
957 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
958 * function pointers are really function descriptors, which contain a
959 * pointer to the real address.
961 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
962 struct printf_spec spec)
965 return string(buf, end, "(null)", spec);
970 ptr = dereference_function_descriptor(ptr);
974 return symbol_string(buf, end, ptr, spec, *fmt);
977 return resource_string(buf, end, ptr, spec, fmt);
978 case 'M': /* Colon separated: 00:01:02:03:04:05 */
979 case 'm': /* Contiguous: 000102030405 */
980 /* [mM]F (FDDI, bit reversed) */
981 return mac_address_string(buf, end, ptr, spec, fmt);
982 case 'I': /* Formatted IP supported
984 * 6: 0001:0203:...:0708
985 * 6c: 1::708 or 1::1.2.3.4
987 case 'i': /* Contiguous:
993 return ip6_addr_string(buf, end, ptr, spec, fmt);
995 return ip4_addr_string(buf, end, ptr, spec, fmt);
999 return uuid_string(buf, end, ptr, spec, fmt);
1001 spec.flags |= SMALL;
1002 if (spec.field_width == -1) {
1003 spec.field_width = 2*sizeof(void *);
1004 spec.flags |= ZEROPAD;
1008 return number(buf, end, (unsigned long) ptr, spec);
1012 * Helper function to decode printf style format.
1013 * Each call decode a token from the format and return the
1014 * number of characters read (or likely the delta where it wants
1015 * to go on the next call).
1016 * The decoded token is returned through the parameters
1018 * 'h', 'l', or 'L' for integer fields
1019 * 'z' support added 23/7/1999 S.H.
1020 * 'z' changed to 'Z' --davidm 1/25/99
1021 * 't' added for ptrdiff_t
1023 * @fmt: the format string
1024 * @type of the token returned
1025 * @flags: various flags such as +, -, # tokens..
1026 * @field_width: overwritten width
1027 * @base: base of the number (octal, hex, ...)
1028 * @precision: precision of a number
1029 * @qualifier: qualifier of a number (long, size_t, ...)
1031 static int format_decode(const char *fmt, struct printf_spec *spec)
1033 const char *start = fmt;
1035 /* we finished early by reading the field width */
1036 if (spec->type == FORMAT_TYPE_WIDTH) {
1037 if (spec->field_width < 0) {
1038 spec->field_width = -spec->field_width;
1039 spec->flags |= LEFT;
1041 spec->type = FORMAT_TYPE_NONE;
1045 /* we finished early by reading the precision */
1046 if (spec->type == FORMAT_TYPE_PRECISION) {
1047 if (spec->precision < 0)
1048 spec->precision = 0;
1050 spec->type = FORMAT_TYPE_NONE;
1055 spec->type = FORMAT_TYPE_NONE;
1057 for (; *fmt ; ++fmt) {
1062 /* Return the current non-format string */
1063 if (fmt != start || !*fmt)
1069 while (1) { /* this also skips first '%' */
1075 case '-': spec->flags |= LEFT; break;
1076 case '+': spec->flags |= PLUS; break;
1077 case ' ': spec->flags |= SPACE; break;
1078 case '#': spec->flags |= SPECIAL; break;
1079 case '0': spec->flags |= ZEROPAD; break;
1080 default: found = false;
1087 /* get field width */
1088 spec->field_width = -1;
1091 spec->field_width = skip_atoi(&fmt);
1092 else if (*fmt == '*') {
1093 /* it's the next argument */
1094 spec->type = FORMAT_TYPE_WIDTH;
1095 return ++fmt - start;
1099 /* get the precision */
1100 spec->precision = -1;
1103 if (isdigit(*fmt)) {
1104 spec->precision = skip_atoi(&fmt);
1105 if (spec->precision < 0)
1106 spec->precision = 0;
1107 } else if (*fmt == '*') {
1108 /* it's the next argument */
1109 spec->type = FORMAT_TYPE_PRECISION;
1110 return ++fmt - start;
1115 /* get the conversion qualifier */
1116 spec->qualifier = -1;
1117 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1118 TOLOWER(*fmt) == 'z' || *fmt == 't') {
1119 spec->qualifier = *fmt++;
1120 if (unlikely(spec->qualifier == *fmt)) {
1121 if (spec->qualifier == 'l') {
1122 spec->qualifier = 'L';
1124 } else if (spec->qualifier == 'h') {
1125 spec->qualifier = 'H';
1135 spec->type = FORMAT_TYPE_CHAR;
1136 return ++fmt - start;
1139 spec->type = FORMAT_TYPE_STR;
1140 return ++fmt - start;
1143 spec->type = FORMAT_TYPE_PTR;
1148 spec->type = FORMAT_TYPE_NRCHARS;
1149 return ++fmt - start;
1152 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1153 return ++fmt - start;
1155 /* integer number formats - set up the flags and "break" */
1161 spec->flags |= SMALL;
1169 spec->flags |= SIGN;
1174 spec->type = FORMAT_TYPE_INVALID;
1178 if (spec->qualifier == 'L')
1179 spec->type = FORMAT_TYPE_LONG_LONG;
1180 else if (spec->qualifier == 'l') {
1181 if (spec->flags & SIGN)
1182 spec->type = FORMAT_TYPE_LONG;
1184 spec->type = FORMAT_TYPE_ULONG;
1185 } else if (TOLOWER(spec->qualifier) == 'z') {
1186 spec->type = FORMAT_TYPE_SIZE_T;
1187 } else if (spec->qualifier == 't') {
1188 spec->type = FORMAT_TYPE_PTRDIFF;
1189 } else if (spec->qualifier == 'H') {
1190 if (spec->flags & SIGN)
1191 spec->type = FORMAT_TYPE_BYTE;
1193 spec->type = FORMAT_TYPE_UBYTE;
1194 } else if (spec->qualifier == 'h') {
1195 if (spec->flags & SIGN)
1196 spec->type = FORMAT_TYPE_SHORT;
1198 spec->type = FORMAT_TYPE_USHORT;
1200 if (spec->flags & SIGN)
1201 spec->type = FORMAT_TYPE_INT;
1203 spec->type = FORMAT_TYPE_UINT;
1206 return ++fmt - start;
1210 * vsnprintf - Format a string and place it in a buffer
1211 * @buf: The buffer to place the result into
1212 * @size: The size of the buffer, including the trailing null space
1213 * @fmt: The format string to use
1214 * @args: Arguments for the format string
1216 * This function follows C99 vsnprintf, but has some extensions:
1217 * %pS output the name of a text symbol with offset
1218 * %ps output the name of a text symbol without offset
1219 * %pF output the name of a function pointer with its offset
1220 * %pf output the name of a function pointer without its offset
1221 * %pR output the address range in a struct resource with decoded flags
1222 * %pr output the address range in a struct resource with raw flags
1223 * %pM output a 6-byte MAC address with colons
1224 * %pm output a 6-byte MAC address without colons
1225 * %pI4 print an IPv4 address without leading zeros
1226 * %pi4 print an IPv4 address with leading zeros
1227 * %pI6 print an IPv6 address with colons
1228 * %pi6 print an IPv6 address without colons
1229 * %pI6c print an IPv6 address as specified by
1230 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
1231 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1235 * The return value is the number of characters which would
1236 * be generated for the given input, excluding the trailing
1237 * '\0', as per ISO C99. If you want to have the exact
1238 * number of characters written into @buf as return value
1239 * (not including the trailing '\0'), use vscnprintf(). If the
1240 * return is greater than or equal to @size, the resulting
1241 * string is truncated.
1243 * Call this function if you are already dealing with a va_list.
1244 * You probably want snprintf() instead.
1246 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1248 unsigned long long num;
1250 struct printf_spec spec = {0};
1252 /* Reject out-of-range values early. Large positive sizes are
1253 used for unknown buffer sizes. */
1254 if (WARN_ON_ONCE((int) size < 0))
1260 /* Make sure end is always >= buf */
1267 const char *old_fmt = fmt;
1268 int read = format_decode(fmt, &spec);
1272 switch (spec.type) {
1273 case FORMAT_TYPE_NONE: {
1276 if (copy > end - str)
1278 memcpy(str, old_fmt, copy);
1284 case FORMAT_TYPE_WIDTH:
1285 spec.field_width = va_arg(args, int);
1288 case FORMAT_TYPE_PRECISION:
1289 spec.precision = va_arg(args, int);
1292 case FORMAT_TYPE_CHAR: {
1295 if (!(spec.flags & LEFT)) {
1296 while (--spec.field_width > 0) {
1303 c = (unsigned char) va_arg(args, int);
1307 while (--spec.field_width > 0) {
1315 case FORMAT_TYPE_STR:
1316 str = string(str, end, va_arg(args, char *), spec);
1319 case FORMAT_TYPE_PTR:
1320 str = pointer(fmt+1, str, end, va_arg(args, void *),
1322 while (isalnum(*fmt))
1326 case FORMAT_TYPE_PERCENT_CHAR:
1332 case FORMAT_TYPE_INVALID:
1338 case FORMAT_TYPE_NRCHARS: {
1339 u8 qualifier = spec.qualifier;
1341 if (qualifier == 'l') {
1342 long *ip = va_arg(args, long *);
1344 } else if (TOLOWER(qualifier) == 'z') {
1345 size_t *ip = va_arg(args, size_t *);
1348 int *ip = va_arg(args, int *);
1355 switch (spec.type) {
1356 case FORMAT_TYPE_LONG_LONG:
1357 num = va_arg(args, long long);
1359 case FORMAT_TYPE_ULONG:
1360 num = va_arg(args, unsigned long);
1362 case FORMAT_TYPE_LONG:
1363 num = va_arg(args, long);
1365 case FORMAT_TYPE_SIZE_T:
1366 num = va_arg(args, size_t);
1368 case FORMAT_TYPE_PTRDIFF:
1369 num = va_arg(args, ptrdiff_t);
1371 case FORMAT_TYPE_UBYTE:
1372 num = (unsigned char) va_arg(args, int);
1374 case FORMAT_TYPE_BYTE:
1375 num = (signed char) va_arg(args, int);
1377 case FORMAT_TYPE_USHORT:
1378 num = (unsigned short) va_arg(args, int);
1380 case FORMAT_TYPE_SHORT:
1381 num = (short) va_arg(args, int);
1383 case FORMAT_TYPE_INT:
1384 num = (int) va_arg(args, int);
1387 num = va_arg(args, unsigned int);
1390 str = number(str, end, num, spec);
1401 /* the trailing null byte doesn't count towards the total */
1405 EXPORT_SYMBOL(vsnprintf);
1408 * vscnprintf - Format a string and place it in a buffer
1409 * @buf: The buffer to place the result into
1410 * @size: The size of the buffer, including the trailing null space
1411 * @fmt: The format string to use
1412 * @args: Arguments for the format string
1414 * The return value is the number of characters which have been written into
1415 * the @buf not including the trailing '\0'. If @size is <= 0 the function
1418 * Call this function if you are already dealing with a va_list.
1419 * You probably want scnprintf() instead.
1421 * See the vsnprintf() documentation for format string extensions over C99.
1423 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1427 i = vsnprintf(buf, size, fmt, args);
1429 return (i >= size) ? (size - 1) : i;
1431 EXPORT_SYMBOL(vscnprintf);
1434 * snprintf - Format a string and place it in a buffer
1435 * @buf: The buffer to place the result into
1436 * @size: The size of the buffer, including the trailing null space
1437 * @fmt: The format string to use
1438 * @...: Arguments for the format string
1440 * The return value is the number of characters which would be
1441 * generated for the given input, excluding the trailing null,
1442 * as per ISO C99. If the return is greater than or equal to
1443 * @size, the resulting string is truncated.
1445 * See the vsnprintf() documentation for format string extensions over C99.
1447 int snprintf(char *buf, size_t size, const char *fmt, ...)
1452 va_start(args, fmt);
1453 i = vsnprintf(buf, size, fmt, args);
1458 EXPORT_SYMBOL(snprintf);
1461 * scnprintf - Format a string and place it in a buffer
1462 * @buf: The buffer to place the result into
1463 * @size: The size of the buffer, including the trailing null space
1464 * @fmt: The format string to use
1465 * @...: Arguments for the format string
1467 * The return value is the number of characters written into @buf not including
1468 * the trailing '\0'. If @size is <= 0 the function returns 0.
1471 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1476 va_start(args, fmt);
1477 i = vsnprintf(buf, size, fmt, args);
1480 return (i >= size) ? (size - 1) : i;
1482 EXPORT_SYMBOL(scnprintf);
1485 * vsprintf - Format a string and place it in a buffer
1486 * @buf: The buffer to place the result into
1487 * @fmt: The format string to use
1488 * @args: Arguments for the format string
1490 * The function returns the number of characters written
1491 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1494 * Call this function if you are already dealing with a va_list.
1495 * You probably want sprintf() instead.
1497 * See the vsnprintf() documentation for format string extensions over C99.
1499 int vsprintf(char *buf, const char *fmt, va_list args)
1501 return vsnprintf(buf, INT_MAX, fmt, args);
1503 EXPORT_SYMBOL(vsprintf);
1506 * sprintf - Format a string and place it in a buffer
1507 * @buf: The buffer to place the result into
1508 * @fmt: The format string to use
1509 * @...: Arguments for the format string
1511 * The function returns the number of characters written
1512 * into @buf. Use snprintf() or scnprintf() in order to avoid
1515 * See the vsnprintf() documentation for format string extensions over C99.
1517 int sprintf(char *buf, const char *fmt, ...)
1522 va_start(args, fmt);
1523 i = vsnprintf(buf, INT_MAX, fmt, args);
1528 EXPORT_SYMBOL(sprintf);
1530 #ifdef CONFIG_BINARY_PRINTF
1533 * vbin_printf() - VA arguments to binary data
1534 * bstr_printf() - Binary data to text string
1538 * vbin_printf - Parse a format string and place args' binary value in a buffer
1539 * @bin_buf: The buffer to place args' binary value
1540 * @size: The size of the buffer(by words(32bits), not characters)
1541 * @fmt: The format string to use
1542 * @args: Arguments for the format string
1544 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1547 * The return value is the number of words(32bits) which would be generated for
1551 * If the return value is greater than @size, the resulting bin_buf is NOT
1552 * valid for bstr_printf().
1554 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1556 struct printf_spec spec = {0};
1559 str = (char *)bin_buf;
1560 end = (char *)(bin_buf + size);
1562 #define save_arg(type) \
1564 if (sizeof(type) == 8) { \
1565 unsigned long long value; \
1566 str = PTR_ALIGN(str, sizeof(u32)); \
1567 value = va_arg(args, unsigned long long); \
1568 if (str + sizeof(type) <= end) { \
1569 *(u32 *)str = *(u32 *)&value; \
1570 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1573 unsigned long value; \
1574 str = PTR_ALIGN(str, sizeof(type)); \
1575 value = va_arg(args, int); \
1576 if (str + sizeof(type) <= end) \
1577 *(typeof(type) *)str = (type)value; \
1579 str += sizeof(type); \
1583 int read = format_decode(fmt, &spec);
1587 switch (spec.type) {
1588 case FORMAT_TYPE_NONE:
1589 case FORMAT_TYPE_INVALID:
1590 case FORMAT_TYPE_PERCENT_CHAR:
1593 case FORMAT_TYPE_WIDTH:
1594 case FORMAT_TYPE_PRECISION:
1598 case FORMAT_TYPE_CHAR:
1602 case FORMAT_TYPE_STR: {
1603 const char *save_str = va_arg(args, char *);
1606 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1607 || (unsigned long)save_str < PAGE_SIZE)
1608 save_str = "(null)";
1609 len = strlen(save_str) + 1;
1610 if (str + len < end)
1611 memcpy(str, save_str, len);
1616 case FORMAT_TYPE_PTR:
1618 /* skip all alphanumeric pointer suffixes */
1619 while (isalnum(*fmt))
1623 case FORMAT_TYPE_NRCHARS: {
1624 /* skip %n 's argument */
1625 u8 qualifier = spec.qualifier;
1627 if (qualifier == 'l')
1628 skip_arg = va_arg(args, long *);
1629 else if (TOLOWER(qualifier) == 'z')
1630 skip_arg = va_arg(args, size_t *);
1632 skip_arg = va_arg(args, int *);
1637 switch (spec.type) {
1639 case FORMAT_TYPE_LONG_LONG:
1640 save_arg(long long);
1642 case FORMAT_TYPE_ULONG:
1643 case FORMAT_TYPE_LONG:
1644 save_arg(unsigned long);
1646 case FORMAT_TYPE_SIZE_T:
1649 case FORMAT_TYPE_PTRDIFF:
1650 save_arg(ptrdiff_t);
1652 case FORMAT_TYPE_UBYTE:
1653 case FORMAT_TYPE_BYTE:
1656 case FORMAT_TYPE_USHORT:
1657 case FORMAT_TYPE_SHORT:
1666 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1669 EXPORT_SYMBOL_GPL(vbin_printf);
1672 * bstr_printf - Format a string from binary arguments and place it in a buffer
1673 * @buf: The buffer to place the result into
1674 * @size: The size of the buffer, including the trailing null space
1675 * @fmt: The format string to use
1676 * @bin_buf: Binary arguments for the format string
1678 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1679 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1680 * a binary buffer that generated by vbin_printf.
1682 * The format follows C99 vsnprintf, but has some extensions:
1683 * see vsnprintf comment for details.
1685 * The return value is the number of characters which would
1686 * be generated for the given input, excluding the trailing
1687 * '\0', as per ISO C99. If you want to have the exact
1688 * number of characters written into @buf as return value
1689 * (not including the trailing '\0'), use vscnprintf(). If the
1690 * return is greater than or equal to @size, the resulting
1691 * string is truncated.
1693 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1695 struct printf_spec spec = {0};
1697 const char *args = (const char *)bin_buf;
1699 if (WARN_ON_ONCE((int) size < 0))
1705 #define get_arg(type) \
1707 typeof(type) value; \
1708 if (sizeof(type) == 8) { \
1709 args = PTR_ALIGN(args, sizeof(u32)); \
1710 *(u32 *)&value = *(u32 *)args; \
1711 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1713 args = PTR_ALIGN(args, sizeof(type)); \
1714 value = *(typeof(type) *)args; \
1716 args += sizeof(type); \
1720 /* Make sure end is always >= buf */
1727 const char *old_fmt = fmt;
1728 int read = format_decode(fmt, &spec);
1732 switch (spec.type) {
1733 case FORMAT_TYPE_NONE: {
1736 if (copy > end - str)
1738 memcpy(str, old_fmt, copy);
1744 case FORMAT_TYPE_WIDTH:
1745 spec.field_width = get_arg(int);
1748 case FORMAT_TYPE_PRECISION:
1749 spec.precision = get_arg(int);
1752 case FORMAT_TYPE_CHAR: {
1755 if (!(spec.flags & LEFT)) {
1756 while (--spec.field_width > 0) {
1762 c = (unsigned char) get_arg(char);
1766 while (--spec.field_width > 0) {
1774 case FORMAT_TYPE_STR: {
1775 const char *str_arg = args;
1776 args += strlen(str_arg) + 1;
1777 str = string(str, end, (char *)str_arg, spec);
1781 case FORMAT_TYPE_PTR:
1782 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1783 while (isalnum(*fmt))
1787 case FORMAT_TYPE_PERCENT_CHAR:
1788 case FORMAT_TYPE_INVALID:
1794 case FORMAT_TYPE_NRCHARS:
1799 unsigned long long num;
1801 switch (spec.type) {
1803 case FORMAT_TYPE_LONG_LONG:
1804 num = get_arg(long long);
1806 case FORMAT_TYPE_ULONG:
1807 case FORMAT_TYPE_LONG:
1808 num = get_arg(unsigned long);
1810 case FORMAT_TYPE_SIZE_T:
1811 num = get_arg(size_t);
1813 case FORMAT_TYPE_PTRDIFF:
1814 num = get_arg(ptrdiff_t);
1816 case FORMAT_TYPE_UBYTE:
1817 num = get_arg(unsigned char);
1819 case FORMAT_TYPE_BYTE:
1820 num = get_arg(signed char);
1822 case FORMAT_TYPE_USHORT:
1823 num = get_arg(unsigned short);
1825 case FORMAT_TYPE_SHORT:
1826 num = get_arg(short);
1828 case FORMAT_TYPE_UINT:
1829 num = get_arg(unsigned int);
1835 str = number(str, end, num, spec);
1837 } /* switch(spec.type) */
1849 /* the trailing null byte doesn't count towards the total */
1852 EXPORT_SYMBOL_GPL(bstr_printf);
1855 * bprintf - Parse a format string and place args' binary value in a buffer
1856 * @bin_buf: The buffer to place args' binary value
1857 * @size: The size of the buffer(by words(32bits), not characters)
1858 * @fmt: The format string to use
1859 * @...: Arguments for the format string
1861 * The function returns the number of words(u32) written
1864 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1869 va_start(args, fmt);
1870 ret = vbin_printf(bin_buf, size, fmt, args);
1875 EXPORT_SYMBOL_GPL(bprintf);
1877 #endif /* CONFIG_BINARY_PRINTF */
1880 * vsscanf - Unformat a buffer into a list of arguments
1881 * @buf: input buffer
1882 * @fmt: format of buffer
1885 int vsscanf(const char *buf, const char *fmt, va_list args)
1887 const char *str = buf;
1896 while (*fmt && *str) {
1897 /* skip any white space in format */
1898 /* white space in format matchs any amount of
1899 * white space, including none, in the input.
1901 if (isspace(*fmt)) {
1902 fmt = skip_spaces(++fmt);
1903 str = skip_spaces(str);
1906 /* anything that is not a conversion must match exactly */
1907 if (*fmt != '%' && *fmt) {
1908 if (*fmt++ != *str++)
1917 /* skip this conversion.
1918 * advance both strings to next white space
1921 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1923 while (!isspace(*str) && *str)
1928 /* get field width */
1931 field_width = skip_atoi(&fmt);
1933 /* get conversion qualifier */
1935 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1936 TOLOWER(*fmt) == 'z') {
1938 if (unlikely(qualifier == *fmt)) {
1939 if (qualifier == 'h') {
1942 } else if (qualifier == 'l') {
1958 char *s = (char *)va_arg(args, char*);
1959 if (field_width == -1)
1963 } while (--field_width > 0 && *str);
1969 char *s = (char *)va_arg(args, char *);
1970 if (field_width == -1)
1971 field_width = SHORT_MAX;
1972 /* first, skip leading white space in buffer */
1973 str = skip_spaces(str);
1975 /* now copy until next white space */
1976 while (*str && !isspace(*str) && field_width--)
1983 /* return number of characters read so far */
1985 int *i = (int *)va_arg(args, int*);
2003 /* looking for '%' in str */
2008 /* invalid format; stop here */
2012 /* have some sort of integer conversion.
2013 * first, skip white space in buffer.
2015 str = skip_spaces(str);
2018 if (is_sign && digit == '-')
2022 || (base == 16 && !isxdigit(digit))
2023 || (base == 10 && !isdigit(digit))
2024 || (base == 8 && (!isdigit(digit) || digit > '7'))
2025 || (base == 0 && !isdigit(digit)))
2028 switch (qualifier) {
2029 case 'H': /* that's 'hh' in format */
2031 signed char *s = (signed char *)va_arg(args, signed char *);
2032 *s = (signed char)simple_strtol(str, &next, base);
2034 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
2035 *s = (unsigned char)simple_strtoul(str, &next, base);
2040 short *s = (short *)va_arg(args, short *);
2041 *s = (short)simple_strtol(str, &next, base);
2043 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
2044 *s = (unsigned short)simple_strtoul(str, &next, base);
2049 long *l = (long *)va_arg(args, long *);
2050 *l = simple_strtol(str, &next, base);
2052 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2053 *l = simple_strtoul(str, &next, base);
2058 long long *l = (long long *)va_arg(args, long long *);
2059 *l = simple_strtoll(str, &next, base);
2061 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2062 *l = simple_strtoull(str, &next, base);
2068 size_t *s = (size_t *)va_arg(args, size_t *);
2069 *s = (size_t)simple_strtoul(str, &next, base);
2074 int *i = (int *)va_arg(args, int *);
2075 *i = (int)simple_strtol(str, &next, base);
2077 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2078 *i = (unsigned int)simple_strtoul(str, &next, base);
2090 * Now we've come all the way through so either the input string or the
2091 * format ended. In the former case, there can be a %n at the current
2092 * position in the format that needs to be filled.
2094 if (*fmt == '%' && *(fmt + 1) == 'n') {
2095 int *p = (int *)va_arg(args, int *);
2101 EXPORT_SYMBOL(vsscanf);
2104 * sscanf - Unformat a buffer into a list of arguments
2105 * @buf: input buffer
2106 * @fmt: formatting of buffer
2107 * @...: resulting arguments
2109 int sscanf(const char *buf, const char *fmt, ...)
2114 va_start(args, fmt);
2115 i = vsscanf(buf, fmt, args);
2120 EXPORT_SYMBOL(sscanf);