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/math64.h>
27 #include <linux/uaccess.h>
28 #include <linux/ioport.h>
29 #include <linux/dcache.h>
30 #include <linux/cred.h>
31 #include <net/addrconf.h>
33 #include <asm/page.h> /* for PAGE_SIZE */
34 #include <asm/sections.h> /* for dereference_function_descriptor() */
36 #include <linux/string_helpers.h>
40 * simple_strtoull - convert a string to an unsigned long long
41 * @cp: The start of the string
42 * @endp: A pointer to the end of the parsed string will be placed here
43 * @base: The number base to use
45 * This function is obsolete. Please use kstrtoull instead.
47 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
49 unsigned long long result;
52 cp = _parse_integer_fixup_radix(cp, &base);
53 rv = _parse_integer(cp, base, &result);
55 cp += (rv & ~KSTRTOX_OVERFLOW);
62 EXPORT_SYMBOL(simple_strtoull);
65 * simple_strtoul - convert a string to an unsigned long
66 * @cp: The start of the string
67 * @endp: A pointer to the end of the parsed string will be placed here
68 * @base: The number base to use
70 * This function is obsolete. Please use kstrtoul instead.
72 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
74 return simple_strtoull(cp, endp, base);
76 EXPORT_SYMBOL(simple_strtoul);
79 * simple_strtol - convert a string to a signed long
80 * @cp: The start of the string
81 * @endp: A pointer to the end of the parsed string will be placed here
82 * @base: The number base to use
84 * This function is obsolete. Please use kstrtol instead.
86 long simple_strtol(const char *cp, char **endp, unsigned int base)
89 return -simple_strtoul(cp + 1, endp, base);
91 return simple_strtoul(cp, endp, base);
93 EXPORT_SYMBOL(simple_strtol);
96 * simple_strtoll - convert a string to a signed long long
97 * @cp: The start of the string
98 * @endp: A pointer to the end of the parsed string will be placed here
99 * @base: The number base to use
101 * This function is obsolete. Please use kstrtoll instead.
103 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
106 return -simple_strtoull(cp + 1, endp, base);
108 return simple_strtoull(cp, endp, base);
110 EXPORT_SYMBOL(simple_strtoll);
112 static noinline_for_stack
113 int skip_atoi(const char **s)
118 i = i*10 + *((*s)++) - '0';
119 } while (isdigit(**s));
124 /* Decimal conversion is by far the most typical, and is used
125 * for /proc and /sys data. This directly impacts e.g. top performance
126 * with many processes running. We optimize it for speed
127 * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
128 * (with permission from the author, Douglas W. Jones).
131 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
132 /* Formats correctly any integer in [0, 999999999] */
133 static noinline_for_stack
134 char *put_dec_full9(char *buf, unsigned q)
139 * Possible ways to approx. divide by 10
140 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
141 * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul)
142 * (x * 0x6667) >> 18 x < 43699
143 * (x * 0x3334) >> 17 x < 16389
144 * (x * 0x199a) >> 16 x < 16389
145 * (x * 0x0ccd) >> 15 x < 16389
146 * (x * 0x0667) >> 14 x < 2739
147 * (x * 0x0334) >> 13 x < 1029
148 * (x * 0x019a) >> 12 x < 1029
149 * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386)
150 * (x * 0x0067) >> 10 x < 179
151 * (x * 0x0034) >> 9 x < 69 same
152 * (x * 0x001a) >> 8 x < 69 same
153 * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386)
154 * (x * 0x0007) >> 6 x < 19
155 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
157 r = (q * (uint64_t)0x1999999a) >> 32;
158 *buf++ = (q - 10 * r) + '0'; /* 1 */
159 q = (r * (uint64_t)0x1999999a) >> 32;
160 *buf++ = (r - 10 * q) + '0'; /* 2 */
161 r = (q * (uint64_t)0x1999999a) >> 32;
162 *buf++ = (q - 10 * r) + '0'; /* 3 */
163 q = (r * (uint64_t)0x1999999a) >> 32;
164 *buf++ = (r - 10 * q) + '0'; /* 4 */
165 r = (q * (uint64_t)0x1999999a) >> 32;
166 *buf++ = (q - 10 * r) + '0'; /* 5 */
167 /* Now value is under 10000, can avoid 64-bit multiply */
168 q = (r * 0x199a) >> 16;
169 *buf++ = (r - 10 * q) + '0'; /* 6 */
170 r = (q * 0xcd) >> 11;
171 *buf++ = (q - 10 * r) + '0'; /* 7 */
172 q = (r * 0xcd) >> 11;
173 *buf++ = (r - 10 * q) + '0'; /* 8 */
174 *buf++ = q + '0'; /* 9 */
179 /* Similar to above but do not pad with zeros.
180 * Code can be easily arranged to print 9 digits too, but our callers
181 * always call put_dec_full9() instead when the number has 9 decimal digits.
183 static noinline_for_stack
184 char *put_dec_trunc8(char *buf, unsigned r)
188 /* Copy of previous function's body with added early returns */
191 r = (r * (uint64_t)0x1999999a) >> 32;
195 q = (r * 0x199a) >> 16; /* r <= 9999 */
196 *buf++ = (r - 10 * q) + '0';
199 r = (q * 0xcd) >> 11; /* q <= 999 */
200 *buf++ = (q - 10 * r) + '0';
203 q = (r * 0xcd) >> 11; /* r <= 99 */
204 *buf++ = (r - 10 * q) + '0';
207 *buf++ = q + '0'; /* q <= 9 */
211 /* There are two algorithms to print larger numbers.
212 * One is generic: divide by 1000000000 and repeatedly print
213 * groups of (up to) 9 digits. It's conceptually simple,
214 * but requires a (unsigned long long) / 1000000000 division.
216 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
217 * manipulates them cleverly and generates groups of 4 decimal digits.
218 * It so happens that it does NOT require long long division.
220 * If long is > 32 bits, division of 64-bit values is relatively easy,
221 * and we will use the first algorithm.
222 * If long long is > 64 bits (strange architecture with VERY large long long),
223 * second algorithm can't be used, and we again use the first one.
225 * Else (if long is 32 bits and long long is 64 bits) we use second one.
228 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
230 /* First algorithm: generic */
233 char *put_dec(char *buf, unsigned long long n)
235 if (n >= 100*1000*1000) {
236 while (n >= 1000*1000*1000)
237 buf = put_dec_full9(buf, do_div(n, 1000*1000*1000));
238 if (n >= 100*1000*1000)
239 return put_dec_full9(buf, n);
241 return put_dec_trunc8(buf, n);
246 /* Second algorithm: valid only for 64-bit long longs */
248 /* See comment in put_dec_full9 for choice of constants */
249 static noinline_for_stack
250 void put_dec_full4(char *buf, unsigned q)
253 r = (q * 0xccd) >> 15;
254 buf[0] = (q - 10 * r) + '0';
255 q = (r * 0xcd) >> 11;
256 buf[1] = (r - 10 * q) + '0';
257 r = (q * 0xcd) >> 11;
258 buf[2] = (q - 10 * r) + '0';
263 * Call put_dec_full4 on x % 10000, return x / 10000.
264 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
265 * holds for all x < 1,128,869,999. The largest value this
266 * helper will ever be asked to convert is 1,125,520,955.
267 * (d1 in the put_dec code, assuming n is all-ones).
270 unsigned put_dec_helper4(char *buf, unsigned x)
272 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
274 put_dec_full4(buf, x - q * 10000);
278 /* Based on code by Douglas W. Jones found at
279 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
280 * (with permission from the author).
281 * Performs no 64-bit division and hence should be fast on 32-bit machines.
284 char *put_dec(char *buf, unsigned long long n)
286 uint32_t d3, d2, d1, q, h;
288 if (n < 100*1000*1000)
289 return put_dec_trunc8(buf, n);
291 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
294 d3 = (h >> 16); /* implicit "& 0xffff" */
296 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
297 q = put_dec_helper4(buf, q);
299 q += 7671 * d3 + 9496 * d2 + 6 * d1;
300 q = put_dec_helper4(buf+4, q);
302 q += 4749 * d3 + 42 * d2;
303 q = put_dec_helper4(buf+8, q);
308 buf = put_dec_trunc8(buf, q);
309 else while (buf[-1] == '0')
318 * Convert passed number to decimal string.
319 * Returns the length of string. On buffer overflow, returns 0.
321 * If speed is not important, use snprintf(). It's easy to read the code.
323 int num_to_str(char *buf, int size, unsigned long long num)
325 char tmp[sizeof(num) * 3];
328 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
333 len = put_dec(tmp, num) - tmp;
338 for (idx = 0; idx < len; ++idx)
339 buf[idx] = tmp[len - idx - 1];
343 #define ZEROPAD 1 /* pad with zero */
344 #define SIGN 2 /* unsigned/signed long */
345 #define PLUS 4 /* show plus */
346 #define SPACE 8 /* space if plus */
347 #define LEFT 16 /* left justified */
348 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
349 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
352 FORMAT_TYPE_NONE, /* Just a string part */
354 FORMAT_TYPE_PRECISION,
358 FORMAT_TYPE_PERCENT_CHAR,
360 FORMAT_TYPE_LONG_LONG,
374 u8 type; /* format_type enum */
375 u8 flags; /* flags to number() */
376 u8 base; /* number base, 8, 10 or 16 only */
377 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
378 s16 field_width; /* width of output field */
379 s16 precision; /* # of digits/chars */
382 static noinline_for_stack
383 char *number(char *buf, char *end, unsigned long long num,
384 struct printf_spec spec)
386 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
387 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
392 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
394 bool is_zero = num == 0LL;
396 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
397 * produces same digits or (maybe lowercased) letters */
398 locase = (spec.flags & SMALL);
399 if (spec.flags & LEFT)
400 spec.flags &= ~ZEROPAD;
402 if (spec.flags & SIGN) {
403 if ((signed long long)num < 0) {
405 num = -(signed long long)num;
407 } else if (spec.flags & PLUS) {
410 } else if (spec.flags & SPACE) {
417 spec.field_width -= 2;
422 /* generate full string in tmp[], in reverse order */
425 tmp[i++] = digits[num] | locase;
426 /* Generic code, for any base:
428 tmp[i++] = (digits[do_div(num,base)] | locase);
431 else if (spec.base != 10) { /* 8 or 16 */
432 int mask = spec.base - 1;
438 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
441 } else { /* base 10 */
442 i = put_dec(tmp, num) - tmp;
445 /* printing 100 using %2d gives "100", not "00" */
446 if (i > spec.precision)
448 /* leading space padding */
449 spec.field_width -= spec.precision;
450 if (!(spec.flags & (ZEROPAD+LEFT))) {
451 while (--spec.field_width >= 0) {
463 /* "0x" / "0" prefix */
465 if (spec.base == 16 || !is_zero) {
470 if (spec.base == 16) {
472 *buf = ('X' | locase);
476 /* zero or space padding */
477 if (!(spec.flags & LEFT)) {
478 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
479 while (--spec.field_width >= 0) {
485 /* hmm even more zero padding? */
486 while (i <= --spec.precision) {
491 /* actual digits of result */
497 /* trailing space padding */
498 while (--spec.field_width >= 0) {
507 static noinline_for_stack
508 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
512 if ((unsigned long)s < PAGE_SIZE)
515 len = strnlen(s, spec.precision);
517 if (!(spec.flags & LEFT)) {
518 while (len < spec.field_width--) {
524 for (i = 0; i < len; ++i) {
529 while (len < spec.field_width--) {
538 static void widen(char *buf, char *end, unsigned len, unsigned spaces)
541 if (buf >= end) /* nowhere to put anything */
544 if (size <= spaces) {
545 memset(buf, ' ', size);
549 if (len > size - spaces)
551 memmove(buf + spaces, buf, len);
553 memset(buf, ' ', spaces);
556 static noinline_for_stack
557 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
560 const char *array[4], *s;
561 const struct dentry *p;
566 case '2': case '3': case '4':
567 depth = fmt[1] - '0';
574 for (i = 0; i < depth; i++, d = p) {
575 p = ACCESS_ONCE(d->d_parent);
576 array[i] = ACCESS_ONCE(d->d_name.name);
585 for (n = 0; n != spec.precision; n++, buf++) {
597 if (n < spec.field_width) {
598 /* we want to pad the sucker */
599 unsigned spaces = spec.field_width - n;
600 if (!(spec.flags & LEFT)) {
601 widen(buf - n, end, n, spaces);
613 static noinline_for_stack
614 char *symbol_string(char *buf, char *end, void *ptr,
615 struct printf_spec spec, const char *fmt)
618 #ifdef CONFIG_KALLSYMS
619 char sym[KSYM_SYMBOL_LEN];
623 ptr = __builtin_extract_return_addr(ptr);
624 value = (unsigned long)ptr;
626 #ifdef CONFIG_KALLSYMS
628 sprint_backtrace(sym, value);
629 else if (*fmt != 'f' && *fmt != 's')
630 sprint_symbol(sym, value);
632 sprint_symbol_no_offset(sym, value);
634 return string(buf, end, sym, spec);
636 spec.field_width = 2 * sizeof(void *);
637 spec.flags |= SPECIAL | SMALL | ZEROPAD;
640 return number(buf, end, value, spec);
644 static noinline_for_stack
645 char *resource_string(char *buf, char *end, struct resource *res,
646 struct printf_spec spec, const char *fmt)
648 #ifndef IO_RSRC_PRINTK_SIZE
649 #define IO_RSRC_PRINTK_SIZE 6
652 #ifndef MEM_RSRC_PRINTK_SIZE
653 #define MEM_RSRC_PRINTK_SIZE 10
655 static const struct printf_spec io_spec = {
657 .field_width = IO_RSRC_PRINTK_SIZE,
659 .flags = SPECIAL | SMALL | ZEROPAD,
661 static const struct printf_spec mem_spec = {
663 .field_width = MEM_RSRC_PRINTK_SIZE,
665 .flags = SPECIAL | SMALL | ZEROPAD,
667 static const struct printf_spec bus_spec = {
671 .flags = SMALL | ZEROPAD,
673 static const struct printf_spec dec_spec = {
678 static const struct printf_spec str_spec = {
683 static const struct printf_spec flag_spec = {
686 .flags = SPECIAL | SMALL,
689 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
690 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
691 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
692 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
693 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
694 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
695 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
696 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
698 char *p = sym, *pend = sym + sizeof(sym);
699 int decode = (fmt[0] == 'R') ? 1 : 0;
700 const struct printf_spec *specp;
703 if (res->flags & IORESOURCE_IO) {
704 p = string(p, pend, "io ", str_spec);
706 } else if (res->flags & IORESOURCE_MEM) {
707 p = string(p, pend, "mem ", str_spec);
709 } else if (res->flags & IORESOURCE_IRQ) {
710 p = string(p, pend, "irq ", str_spec);
712 } else if (res->flags & IORESOURCE_DMA) {
713 p = string(p, pend, "dma ", str_spec);
715 } else if (res->flags & IORESOURCE_BUS) {
716 p = string(p, pend, "bus ", str_spec);
719 p = string(p, pend, "??? ", str_spec);
723 if (decode && res->flags & IORESOURCE_UNSET) {
724 p = string(p, pend, "size ", str_spec);
725 p = number(p, pend, resource_size(res), *specp);
727 p = number(p, pend, res->start, *specp);
728 if (res->start != res->end) {
730 p = number(p, pend, res->end, *specp);
734 if (res->flags & IORESOURCE_MEM_64)
735 p = string(p, pend, " 64bit", str_spec);
736 if (res->flags & IORESOURCE_PREFETCH)
737 p = string(p, pend, " pref", str_spec);
738 if (res->flags & IORESOURCE_WINDOW)
739 p = string(p, pend, " window", str_spec);
740 if (res->flags & IORESOURCE_DISABLED)
741 p = string(p, pend, " disabled", str_spec);
743 p = string(p, pend, " flags ", str_spec);
744 p = number(p, pend, res->flags, flag_spec);
749 return string(buf, end, sym, spec);
752 static noinline_for_stack
753 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
756 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
757 negative value, fallback to the default */
760 if (spec.field_width == 0)
761 /* nothing to print */
764 if (ZERO_OR_NULL_PTR(addr))
766 return string(buf, end, NULL, spec);
783 if (spec.field_width > 0)
784 len = min_t(int, spec.field_width, 64);
786 for (i = 0; i < len && buf < end - 1; i++) {
787 buf = hex_byte_pack(buf, addr[i]);
789 if (buf < end && separator && i != len - 1)
796 static noinline_for_stack
797 char *mac_address_string(char *buf, char *end, u8 *addr,
798 struct printf_spec spec, const char *fmt)
800 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
804 bool reversed = false;
820 for (i = 0; i < 6; i++) {
822 p = hex_byte_pack(p, addr[5 - i]);
824 p = hex_byte_pack(p, addr[i]);
826 if (fmt[0] == 'M' && i != 5)
831 return string(buf, end, mac_addr, spec);
834 static noinline_for_stack
835 char *ip4_string(char *p, const u8 *addr, const char *fmt)
838 bool leading_zeros = (fmt[0] == 'i');
863 for (i = 0; i < 4; i++) {
864 char temp[3]; /* hold each IP quad in reverse order */
865 int digits = put_dec_trunc8(temp, addr[index]) - temp;
872 /* reverse the digits in the quad */
884 static noinline_for_stack
885 char *ip6_compressed_string(char *p, const char *addr)
888 unsigned char zerolength[8];
893 bool needcolon = false;
897 memcpy(&in6, addr, sizeof(struct in6_addr));
899 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
901 memset(zerolength, 0, sizeof(zerolength));
908 /* find position of longest 0 run */
909 for (i = 0; i < range; i++) {
910 for (j = i; j < range; j++) {
911 if (in6.s6_addr16[j] != 0)
916 for (i = 0; i < range; i++) {
917 if (zerolength[i] > longest) {
918 longest = zerolength[i];
922 if (longest == 1) /* don't compress a single 0 */
926 for (i = 0; i < range; i++) {
928 if (needcolon || i == 0)
939 /* hex u16 without leading 0s */
940 word = ntohs(in6.s6_addr16[i]);
945 p = hex_byte_pack(p, hi);
947 *p++ = hex_asc_lo(hi);
948 p = hex_byte_pack(p, lo);
951 p = hex_byte_pack(p, lo);
953 *p++ = hex_asc_lo(lo);
960 p = ip4_string(p, &in6.s6_addr[12], "I4");
967 static noinline_for_stack
968 char *ip6_string(char *p, const char *addr, const char *fmt)
972 for (i = 0; i < 8; i++) {
973 p = hex_byte_pack(p, *addr++);
974 p = hex_byte_pack(p, *addr++);
975 if (fmt[0] == 'I' && i != 7)
983 static noinline_for_stack
984 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
985 struct printf_spec spec, const char *fmt)
987 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
989 if (fmt[0] == 'I' && fmt[2] == 'c')
990 ip6_compressed_string(ip6_addr, addr);
992 ip6_string(ip6_addr, addr, fmt);
994 return string(buf, end, ip6_addr, spec);
997 static noinline_for_stack
998 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
999 struct printf_spec spec, const char *fmt)
1001 char ip4_addr[sizeof("255.255.255.255")];
1003 ip4_string(ip4_addr, addr, fmt);
1005 return string(buf, end, ip4_addr, spec);
1008 static noinline_for_stack
1009 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1010 struct printf_spec spec, const char *fmt)
1012 bool have_p = false, have_s = false, have_f = false, have_c = false;
1013 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1014 sizeof(":12345") + sizeof("/123456789") +
1015 sizeof("%1234567890")];
1016 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1017 const u8 *addr = (const u8 *) &sa->sin6_addr;
1018 char fmt6[2] = { fmt[0], '6' };
1022 while (isalpha(*++fmt)) {
1039 if (have_p || have_s || have_f) {
1044 if (fmt6[0] == 'I' && have_c)
1045 p = ip6_compressed_string(ip6_addr + off, addr);
1047 p = ip6_string(ip6_addr + off, addr, fmt6);
1049 if (have_p || have_s || have_f)
1054 p = number(p, pend, ntohs(sa->sin6_port), spec);
1058 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1059 IPV6_FLOWINFO_MASK), spec);
1063 p = number(p, pend, sa->sin6_scope_id, spec);
1067 return string(buf, end, ip6_addr, spec);
1070 static noinline_for_stack
1071 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1072 struct printf_spec spec, const char *fmt)
1074 bool have_p = false;
1075 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1076 char *pend = ip4_addr + sizeof(ip4_addr);
1077 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1078 char fmt4[3] = { fmt[0], '4', 0 };
1081 while (isalpha(*++fmt)) {
1095 p = ip4_string(ip4_addr, addr, fmt4);
1098 p = number(p, pend, ntohs(sa->sin_port), spec);
1102 return string(buf, end, ip4_addr, spec);
1105 static noinline_for_stack
1106 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1111 unsigned int flags = 0;
1114 if (spec.field_width == 0)
1115 return buf; /* nothing to print */
1117 if (ZERO_OR_NULL_PTR(addr))
1118 return string(buf, end, NULL, spec); /* NULL pointer */
1122 switch (fmt[count++]) {
1124 flags |= ESCAPE_ANY;
1127 flags |= ESCAPE_SPECIAL;
1130 flags |= ESCAPE_HEX;
1133 flags |= ESCAPE_NULL;
1136 flags |= ESCAPE_OCTAL;
1142 flags |= ESCAPE_SPACE;
1151 flags = ESCAPE_ANY_NP;
1153 len = spec.field_width < 0 ? 1 : spec.field_width;
1155 /* Ignore the error. We print as many characters as we can */
1156 string_escape_mem(addr, len, &buf, end - buf, flags, NULL);
1161 static noinline_for_stack
1162 char *uuid_string(char *buf, char *end, const u8 *addr,
1163 struct printf_spec spec, const char *fmt)
1165 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1168 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1169 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1170 const u8 *index = be;
1175 uc = true; /* fall-through */
1184 for (i = 0; i < 16; i++) {
1185 p = hex_byte_pack(p, addr[index[i]]);
1205 return string(buf, end, uuid, spec);
1209 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
1210 struct printf_spec spec)
1212 spec.flags |= SPECIAL | SMALL | ZEROPAD;
1213 if (spec.field_width == -1)
1214 spec.field_width = 2 + 2 * sizeof(netdev_features_t);
1217 return number(buf, end, *(const netdev_features_t *)addr, spec);
1220 static noinline_for_stack
1221 char *address_val(char *buf, char *end, const void *addr,
1222 struct printf_spec spec, const char *fmt)
1224 unsigned long long num;
1226 spec.flags |= SPECIAL | SMALL | ZEROPAD;
1231 num = *(const dma_addr_t *)addr;
1232 spec.field_width = sizeof(dma_addr_t) * 2 + 2;
1236 num = *(const phys_addr_t *)addr;
1237 spec.field_width = sizeof(phys_addr_t) * 2 + 2;
1241 return number(buf, end, num, spec);
1244 int kptr_restrict __read_mostly;
1247 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1248 * by an extra set of alphanumeric characters that are extended format
1251 * Right now we handle:
1253 * - 'F' For symbolic function descriptor pointers with offset
1254 * - 'f' For simple symbolic function names without offset
1255 * - 'S' For symbolic direct pointers with offset
1256 * - 's' For symbolic direct pointers without offset
1257 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1258 * - 'B' For backtraced symbolic direct pointers with offset
1259 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1260 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1261 * - 'M' For a 6-byte MAC address, it prints the address in the
1262 * usual colon-separated hex notation
1263 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1264 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1265 * with a dash-separated hex notation
1266 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1267 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1268 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1269 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1271 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1272 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1273 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1274 * IPv6 omits the colons (01020304...0f)
1275 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1277 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1278 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1279 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1280 * - 'I[6S]c' for IPv6 addresses printed as specified by
1281 * http://tools.ietf.org/html/rfc5952
1282 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1283 * of the following flags (see string_escape_mem() for the
1286 * c - ESCAPE_SPECIAL
1292 * By default ESCAPE_ANY_NP is used.
1293 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1294 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1295 * Options for %pU are:
1296 * b big endian lower case hex (default)
1297 * B big endian UPPER case hex
1298 * l little endian lower case hex
1299 * L little endian UPPER case hex
1300 * big endian output byte order is:
1301 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1302 * little endian output byte order is:
1303 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1304 * - 'V' For a struct va_format which contains a format string * and va_list *,
1305 * call vsnprintf(->format, *->va_list).
1306 * Implements a "recursive vsnprintf".
1307 * Do not use this feature without some mechanism to verify the
1308 * correctness of the format string and va_list arguments.
1309 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1310 * - 'NF' For a netdev_features_t
1311 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1312 * a certain separator (' ' by default):
1316 * The maximum supported length is 64 bytes of the input. Consider
1317 * to use print_hex_dump() for the larger input.
1318 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1319 * (default assumed to be phys_addr_t, passed by reference)
1320 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1321 * - 'D[234]' Same as 'd' but for a struct file
1323 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1324 * function pointers are really function descriptors, which contain a
1325 * pointer to the real address.
1327 static noinline_for_stack
1328 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1329 struct printf_spec spec)
1331 int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
1333 if (!ptr && *fmt != 'K') {
1335 * Print (null) with the same width as a pointer so it makes
1336 * tabular output look nice.
1338 if (spec.field_width == -1)
1339 spec.field_width = default_width;
1340 return string(buf, end, "(null)", spec);
1346 ptr = dereference_function_descriptor(ptr);
1351 return symbol_string(buf, end, ptr, spec, fmt);
1354 return resource_string(buf, end, ptr, spec, fmt);
1356 return hex_string(buf, end, ptr, spec, fmt);
1357 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1358 case 'm': /* Contiguous: 000102030405 */
1360 /* [mM]R (Reverse order; Bluetooth) */
1361 return mac_address_string(buf, end, ptr, spec, fmt);
1362 case 'I': /* Formatted IP supported
1364 * 6: 0001:0203:...:0708
1365 * 6c: 1::708 or 1::1.2.3.4
1367 case 'i': /* Contiguous:
1368 * 4: 001.002.003.004
1373 return ip6_addr_string(buf, end, ptr, spec, fmt);
1375 return ip4_addr_string(buf, end, ptr, spec, fmt);
1378 struct sockaddr raw;
1379 struct sockaddr_in v4;
1380 struct sockaddr_in6 v6;
1383 switch (sa->raw.sa_family) {
1385 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1387 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1389 return string(buf, end, "(invalid address)", spec);
1394 return escaped_string(buf, end, ptr, spec, fmt);
1396 return uuid_string(buf, end, ptr, spec, fmt);
1401 va_copy(va, *((struct va_format *)ptr)->va);
1402 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1403 ((struct va_format *)ptr)->fmt, va);
1409 * %pK cannot be used in IRQ context because its test
1410 * for CAP_SYSLOG would be meaningless.
1412 if (kptr_restrict && (in_irq() || in_serving_softirq() ||
1414 if (spec.field_width == -1)
1415 spec.field_width = default_width;
1416 return string(buf, end, "pK-error", spec);
1419 switch (kptr_restrict) {
1421 /* Always print %pK values */
1425 * Only print the real pointer value if the current
1426 * process has CAP_SYSLOG and is running with the
1427 * same credentials it started with. This is because
1428 * access to files is checked at open() time, but %pK
1429 * checks permission at read() time. We don't want to
1430 * leak pointer values if a binary opens a file using
1431 * %pK and then elevates privileges before reading it.
1433 const struct cred *cred = current_cred();
1435 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1436 !uid_eq(cred->euid, cred->uid) ||
1437 !gid_eq(cred->egid, cred->gid))
1443 /* Always print 0's for %pK */
1452 return netdev_feature_string(buf, end, ptr, spec);
1456 return address_val(buf, end, ptr, spec, fmt);
1458 return dentry_name(buf, end, ptr, spec, fmt);
1460 return dentry_name(buf, end,
1461 ((const struct file *)ptr)->f_path.dentry,
1464 spec.flags |= SMALL;
1465 if (spec.field_width == -1) {
1466 spec.field_width = default_width;
1467 spec.flags |= ZEROPAD;
1471 return number(buf, end, (unsigned long) ptr, spec);
1475 * Helper function to decode printf style format.
1476 * Each call decode a token from the format and return the
1477 * number of characters read (or likely the delta where it wants
1478 * to go on the next call).
1479 * The decoded token is returned through the parameters
1481 * 'h', 'l', or 'L' for integer fields
1482 * 'z' support added 23/7/1999 S.H.
1483 * 'z' changed to 'Z' --davidm 1/25/99
1484 * 't' added for ptrdiff_t
1486 * @fmt: the format string
1487 * @type of the token returned
1488 * @flags: various flags such as +, -, # tokens..
1489 * @field_width: overwritten width
1490 * @base: base of the number (octal, hex, ...)
1491 * @precision: precision of a number
1492 * @qualifier: qualifier of a number (long, size_t, ...)
1494 static noinline_for_stack
1495 int format_decode(const char *fmt, struct printf_spec *spec)
1497 const char *start = fmt;
1499 /* we finished early by reading the field width */
1500 if (spec->type == FORMAT_TYPE_WIDTH) {
1501 if (spec->field_width < 0) {
1502 spec->field_width = -spec->field_width;
1503 spec->flags |= LEFT;
1505 spec->type = FORMAT_TYPE_NONE;
1509 /* we finished early by reading the precision */
1510 if (spec->type == FORMAT_TYPE_PRECISION) {
1511 if (spec->precision < 0)
1512 spec->precision = 0;
1514 spec->type = FORMAT_TYPE_NONE;
1519 spec->type = FORMAT_TYPE_NONE;
1521 for (; *fmt ; ++fmt) {
1526 /* Return the current non-format string */
1527 if (fmt != start || !*fmt)
1533 while (1) { /* this also skips first '%' */
1539 case '-': spec->flags |= LEFT; break;
1540 case '+': spec->flags |= PLUS; break;
1541 case ' ': spec->flags |= SPACE; break;
1542 case '#': spec->flags |= SPECIAL; break;
1543 case '0': spec->flags |= ZEROPAD; break;
1544 default: found = false;
1551 /* get field width */
1552 spec->field_width = -1;
1555 spec->field_width = skip_atoi(&fmt);
1556 else if (*fmt == '*') {
1557 /* it's the next argument */
1558 spec->type = FORMAT_TYPE_WIDTH;
1559 return ++fmt - start;
1563 /* get the precision */
1564 spec->precision = -1;
1567 if (isdigit(*fmt)) {
1568 spec->precision = skip_atoi(&fmt);
1569 if (spec->precision < 0)
1570 spec->precision = 0;
1571 } else if (*fmt == '*') {
1572 /* it's the next argument */
1573 spec->type = FORMAT_TYPE_PRECISION;
1574 return ++fmt - start;
1579 /* get the conversion qualifier */
1580 spec->qualifier = -1;
1581 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1582 _tolower(*fmt) == 'z' || *fmt == 't') {
1583 spec->qualifier = *fmt++;
1584 if (unlikely(spec->qualifier == *fmt)) {
1585 if (spec->qualifier == 'l') {
1586 spec->qualifier = 'L';
1588 } else if (spec->qualifier == 'h') {
1589 spec->qualifier = 'H';
1599 spec->type = FORMAT_TYPE_CHAR;
1600 return ++fmt - start;
1603 spec->type = FORMAT_TYPE_STR;
1604 return ++fmt - start;
1607 spec->type = FORMAT_TYPE_PTR;
1608 return ++fmt - start;
1611 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1612 return ++fmt - start;
1614 /* integer number formats - set up the flags and "break" */
1620 spec->flags |= SMALL;
1628 spec->flags |= SIGN;
1634 * Since %n poses a greater security risk than utility, treat
1635 * it as an invalid format specifier. Warn about its use so
1636 * that new instances don't get added.
1638 WARN_ONCE(1, "Please remove ignored %%n in '%s'\n", fmt);
1642 spec->type = FORMAT_TYPE_INVALID;
1646 if (spec->qualifier == 'L')
1647 spec->type = FORMAT_TYPE_LONG_LONG;
1648 else if (spec->qualifier == 'l') {
1649 if (spec->flags & SIGN)
1650 spec->type = FORMAT_TYPE_LONG;
1652 spec->type = FORMAT_TYPE_ULONG;
1653 } else if (_tolower(spec->qualifier) == 'z') {
1654 spec->type = FORMAT_TYPE_SIZE_T;
1655 } else if (spec->qualifier == 't') {
1656 spec->type = FORMAT_TYPE_PTRDIFF;
1657 } else if (spec->qualifier == 'H') {
1658 if (spec->flags & SIGN)
1659 spec->type = FORMAT_TYPE_BYTE;
1661 spec->type = FORMAT_TYPE_UBYTE;
1662 } else if (spec->qualifier == 'h') {
1663 if (spec->flags & SIGN)
1664 spec->type = FORMAT_TYPE_SHORT;
1666 spec->type = FORMAT_TYPE_USHORT;
1668 if (spec->flags & SIGN)
1669 spec->type = FORMAT_TYPE_INT;
1671 spec->type = FORMAT_TYPE_UINT;
1674 return ++fmt - start;
1678 * vsnprintf - Format a string and place it in a buffer
1679 * @buf: The buffer to place the result into
1680 * @size: The size of the buffer, including the trailing null space
1681 * @fmt: The format string to use
1682 * @args: Arguments for the format string
1684 * This function follows C99 vsnprintf, but has some extensions:
1685 * %pS output the name of a text symbol with offset
1686 * %ps output the name of a text symbol without offset
1687 * %pF output the name of a function pointer with its offset
1688 * %pf output the name of a function pointer without its offset
1689 * %pB output the name of a backtrace symbol with its offset
1690 * %pR output the address range in a struct resource with decoded flags
1691 * %pr output the address range in a struct resource with raw flags
1692 * %pM output a 6-byte MAC address with colons
1693 * %pMR output a 6-byte MAC address with colons in reversed order
1694 * %pMF output a 6-byte MAC address with dashes
1695 * %pm output a 6-byte MAC address without colons
1696 * %pmR output a 6-byte MAC address without colons in reversed order
1697 * %pI4 print an IPv4 address without leading zeros
1698 * %pi4 print an IPv4 address with leading zeros
1699 * %pI6 print an IPv6 address with colons
1700 * %pi6 print an IPv6 address without colons
1701 * %pI6c print an IPv6 address as specified by RFC 5952
1702 * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1703 * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1704 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1706 * %*pE[achnops] print an escaped buffer
1707 * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1708 * bytes of the input)
1711 * ** Please update Documentation/printk-formats.txt when making changes **
1713 * The return value is the number of characters which would
1714 * be generated for the given input, excluding the trailing
1715 * '\0', as per ISO C99. If you want to have the exact
1716 * number of characters written into @buf as return value
1717 * (not including the trailing '\0'), use vscnprintf(). If the
1718 * return is greater than or equal to @size, the resulting
1719 * string is truncated.
1721 * If you're not already dealing with a va_list consider using snprintf().
1723 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1725 unsigned long long num;
1727 struct printf_spec spec = {0};
1729 /* Reject out-of-range values early. Large positive sizes are
1730 used for unknown buffer sizes. */
1731 if (WARN_ON_ONCE(size > INT_MAX))
1737 /* Make sure end is always >= buf */
1744 const char *old_fmt = fmt;
1745 int read = format_decode(fmt, &spec);
1749 switch (spec.type) {
1750 case FORMAT_TYPE_NONE: {
1753 if (copy > end - str)
1755 memcpy(str, old_fmt, copy);
1761 case FORMAT_TYPE_WIDTH:
1762 spec.field_width = va_arg(args, int);
1765 case FORMAT_TYPE_PRECISION:
1766 spec.precision = va_arg(args, int);
1769 case FORMAT_TYPE_CHAR: {
1772 if (!(spec.flags & LEFT)) {
1773 while (--spec.field_width > 0) {
1780 c = (unsigned char) va_arg(args, int);
1784 while (--spec.field_width > 0) {
1792 case FORMAT_TYPE_STR:
1793 str = string(str, end, va_arg(args, char *), spec);
1796 case FORMAT_TYPE_PTR:
1797 str = pointer(fmt, str, end, va_arg(args, void *),
1799 while (isalnum(*fmt))
1803 case FORMAT_TYPE_PERCENT_CHAR:
1809 case FORMAT_TYPE_INVALID:
1816 switch (spec.type) {
1817 case FORMAT_TYPE_LONG_LONG:
1818 num = va_arg(args, long long);
1820 case FORMAT_TYPE_ULONG:
1821 num = va_arg(args, unsigned long);
1823 case FORMAT_TYPE_LONG:
1824 num = va_arg(args, long);
1826 case FORMAT_TYPE_SIZE_T:
1827 if (spec.flags & SIGN)
1828 num = va_arg(args, ssize_t);
1830 num = va_arg(args, size_t);
1832 case FORMAT_TYPE_PTRDIFF:
1833 num = va_arg(args, ptrdiff_t);
1835 case FORMAT_TYPE_UBYTE:
1836 num = (unsigned char) va_arg(args, int);
1838 case FORMAT_TYPE_BYTE:
1839 num = (signed char) va_arg(args, int);
1841 case FORMAT_TYPE_USHORT:
1842 num = (unsigned short) va_arg(args, int);
1844 case FORMAT_TYPE_SHORT:
1845 num = (short) va_arg(args, int);
1847 case FORMAT_TYPE_INT:
1848 num = (int) va_arg(args, int);
1851 num = va_arg(args, unsigned int);
1854 str = number(str, end, num, spec);
1865 /* the trailing null byte doesn't count towards the total */
1869 EXPORT_SYMBOL(vsnprintf);
1872 * vscnprintf - Format a string and place it in a buffer
1873 * @buf: The buffer to place the result into
1874 * @size: The size of the buffer, including the trailing null space
1875 * @fmt: The format string to use
1876 * @args: Arguments for the format string
1878 * The return value is the number of characters which have been written into
1879 * the @buf not including the trailing '\0'. If @size is == 0 the function
1882 * If you're not already dealing with a va_list consider using scnprintf().
1884 * See the vsnprintf() documentation for format string extensions over C99.
1886 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1890 i = vsnprintf(buf, size, fmt, args);
1892 if (likely(i < size))
1898 EXPORT_SYMBOL(vscnprintf);
1901 * snprintf - Format a string and place it in a buffer
1902 * @buf: The buffer to place the result into
1903 * @size: The size of the buffer, including the trailing null space
1904 * @fmt: The format string to use
1905 * @...: Arguments for the format string
1907 * The return value is the number of characters which would be
1908 * generated for the given input, excluding the trailing null,
1909 * as per ISO C99. If the return is greater than or equal to
1910 * @size, the resulting string is truncated.
1912 * See the vsnprintf() documentation for format string extensions over C99.
1914 int snprintf(char *buf, size_t size, const char *fmt, ...)
1919 va_start(args, fmt);
1920 i = vsnprintf(buf, size, fmt, args);
1925 EXPORT_SYMBOL(snprintf);
1928 * scnprintf - Format a string and place it in a buffer
1929 * @buf: The buffer to place the result into
1930 * @size: The size of the buffer, including the trailing null space
1931 * @fmt: The format string to use
1932 * @...: Arguments for the format string
1934 * The return value is the number of characters written into @buf not including
1935 * the trailing '\0'. If @size is == 0 the function returns 0.
1938 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1943 va_start(args, fmt);
1944 i = vscnprintf(buf, size, fmt, args);
1949 EXPORT_SYMBOL(scnprintf);
1952 * vsprintf - Format a string and place it in a buffer
1953 * @buf: The buffer to place the result into
1954 * @fmt: The format string to use
1955 * @args: Arguments for the format string
1957 * The function returns the number of characters written
1958 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1961 * If you're not already dealing with a va_list consider using sprintf().
1963 * See the vsnprintf() documentation for format string extensions over C99.
1965 int vsprintf(char *buf, const char *fmt, va_list args)
1967 return vsnprintf(buf, INT_MAX, fmt, args);
1969 EXPORT_SYMBOL(vsprintf);
1972 * sprintf - Format a string and place it in a buffer
1973 * @buf: The buffer to place the result into
1974 * @fmt: The format string to use
1975 * @...: Arguments for the format string
1977 * The function returns the number of characters written
1978 * into @buf. Use snprintf() or scnprintf() in order to avoid
1981 * See the vsnprintf() documentation for format string extensions over C99.
1983 int sprintf(char *buf, const char *fmt, ...)
1988 va_start(args, fmt);
1989 i = vsnprintf(buf, INT_MAX, fmt, args);
1994 EXPORT_SYMBOL(sprintf);
1996 #ifdef CONFIG_BINARY_PRINTF
1999 * vbin_printf() - VA arguments to binary data
2000 * bstr_printf() - Binary data to text string
2004 * vbin_printf - Parse a format string and place args' binary value in a buffer
2005 * @bin_buf: The buffer to place args' binary value
2006 * @size: The size of the buffer(by words(32bits), not characters)
2007 * @fmt: The format string to use
2008 * @args: Arguments for the format string
2010 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2013 * The return value is the number of words(32bits) which would be generated for
2017 * If the return value is greater than @size, the resulting bin_buf is NOT
2018 * valid for bstr_printf().
2020 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2022 struct printf_spec spec = {0};
2025 str = (char *)bin_buf;
2026 end = (char *)(bin_buf + size);
2028 #define save_arg(type) \
2030 if (sizeof(type) == 8) { \
2031 unsigned long long value; \
2032 str = PTR_ALIGN(str, sizeof(u32)); \
2033 value = va_arg(args, unsigned long long); \
2034 if (str + sizeof(type) <= end) { \
2035 *(u32 *)str = *(u32 *)&value; \
2036 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2039 unsigned long value; \
2040 str = PTR_ALIGN(str, sizeof(type)); \
2041 value = va_arg(args, int); \
2042 if (str + sizeof(type) <= end) \
2043 *(typeof(type) *)str = (type)value; \
2045 str += sizeof(type); \
2049 int read = format_decode(fmt, &spec);
2053 switch (spec.type) {
2054 case FORMAT_TYPE_NONE:
2055 case FORMAT_TYPE_INVALID:
2056 case FORMAT_TYPE_PERCENT_CHAR:
2059 case FORMAT_TYPE_WIDTH:
2060 case FORMAT_TYPE_PRECISION:
2064 case FORMAT_TYPE_CHAR:
2068 case FORMAT_TYPE_STR: {
2069 const char *save_str = va_arg(args, char *);
2072 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2073 || (unsigned long)save_str < PAGE_SIZE)
2074 save_str = "(null)";
2075 len = strlen(save_str) + 1;
2076 if (str + len < end)
2077 memcpy(str, save_str, len);
2082 case FORMAT_TYPE_PTR:
2084 /* skip all alphanumeric pointer suffixes */
2085 while (isalnum(*fmt))
2090 switch (spec.type) {
2092 case FORMAT_TYPE_LONG_LONG:
2093 save_arg(long long);
2095 case FORMAT_TYPE_ULONG:
2096 case FORMAT_TYPE_LONG:
2097 save_arg(unsigned long);
2099 case FORMAT_TYPE_SIZE_T:
2102 case FORMAT_TYPE_PTRDIFF:
2103 save_arg(ptrdiff_t);
2105 case FORMAT_TYPE_UBYTE:
2106 case FORMAT_TYPE_BYTE:
2109 case FORMAT_TYPE_USHORT:
2110 case FORMAT_TYPE_SHORT:
2119 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2122 EXPORT_SYMBOL_GPL(vbin_printf);
2125 * bstr_printf - Format a string from binary arguments and place it in a buffer
2126 * @buf: The buffer to place the result into
2127 * @size: The size of the buffer, including the trailing null space
2128 * @fmt: The format string to use
2129 * @bin_buf: Binary arguments for the format string
2131 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2132 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2133 * a binary buffer that generated by vbin_printf.
2135 * The format follows C99 vsnprintf, but has some extensions:
2136 * see vsnprintf comment for details.
2138 * The return value is the number of characters which would
2139 * be generated for the given input, excluding the trailing
2140 * '\0', as per ISO C99. If you want to have the exact
2141 * number of characters written into @buf as return value
2142 * (not including the trailing '\0'), use vscnprintf(). If the
2143 * return is greater than or equal to @size, the resulting
2144 * string is truncated.
2146 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2148 struct printf_spec spec = {0};
2150 const char *args = (const char *)bin_buf;
2152 if (WARN_ON_ONCE((int) size < 0))
2158 #define get_arg(type) \
2160 typeof(type) value; \
2161 if (sizeof(type) == 8) { \
2162 args = PTR_ALIGN(args, sizeof(u32)); \
2163 *(u32 *)&value = *(u32 *)args; \
2164 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2166 args = PTR_ALIGN(args, sizeof(type)); \
2167 value = *(typeof(type) *)args; \
2169 args += sizeof(type); \
2173 /* Make sure end is always >= buf */
2180 const char *old_fmt = fmt;
2181 int read = format_decode(fmt, &spec);
2185 switch (spec.type) {
2186 case FORMAT_TYPE_NONE: {
2189 if (copy > end - str)
2191 memcpy(str, old_fmt, copy);
2197 case FORMAT_TYPE_WIDTH:
2198 spec.field_width = get_arg(int);
2201 case FORMAT_TYPE_PRECISION:
2202 spec.precision = get_arg(int);
2205 case FORMAT_TYPE_CHAR: {
2208 if (!(spec.flags & LEFT)) {
2209 while (--spec.field_width > 0) {
2215 c = (unsigned char) get_arg(char);
2219 while (--spec.field_width > 0) {
2227 case FORMAT_TYPE_STR: {
2228 const char *str_arg = args;
2229 args += strlen(str_arg) + 1;
2230 str = string(str, end, (char *)str_arg, spec);
2234 case FORMAT_TYPE_PTR:
2235 str = pointer(fmt, str, end, get_arg(void *), spec);
2236 while (isalnum(*fmt))
2240 case FORMAT_TYPE_PERCENT_CHAR:
2241 case FORMAT_TYPE_INVALID:
2248 unsigned long long num;
2250 switch (spec.type) {
2252 case FORMAT_TYPE_LONG_LONG:
2253 num = get_arg(long long);
2255 case FORMAT_TYPE_ULONG:
2256 case FORMAT_TYPE_LONG:
2257 num = get_arg(unsigned long);
2259 case FORMAT_TYPE_SIZE_T:
2260 num = get_arg(size_t);
2262 case FORMAT_TYPE_PTRDIFF:
2263 num = get_arg(ptrdiff_t);
2265 case FORMAT_TYPE_UBYTE:
2266 num = get_arg(unsigned char);
2268 case FORMAT_TYPE_BYTE:
2269 num = get_arg(signed char);
2271 case FORMAT_TYPE_USHORT:
2272 num = get_arg(unsigned short);
2274 case FORMAT_TYPE_SHORT:
2275 num = get_arg(short);
2277 case FORMAT_TYPE_UINT:
2278 num = get_arg(unsigned int);
2284 str = number(str, end, num, spec);
2286 } /* switch(spec.type) */
2298 /* the trailing null byte doesn't count towards the total */
2301 EXPORT_SYMBOL_GPL(bstr_printf);
2304 * bprintf - Parse a format string and place args' binary value in a buffer
2305 * @bin_buf: The buffer to place args' binary value
2306 * @size: The size of the buffer(by words(32bits), not characters)
2307 * @fmt: The format string to use
2308 * @...: Arguments for the format string
2310 * The function returns the number of words(u32) written
2313 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2318 va_start(args, fmt);
2319 ret = vbin_printf(bin_buf, size, fmt, args);
2324 EXPORT_SYMBOL_GPL(bprintf);
2326 #endif /* CONFIG_BINARY_PRINTF */
2329 * vsscanf - Unformat a buffer into a list of arguments
2330 * @buf: input buffer
2331 * @fmt: format of buffer
2334 int vsscanf(const char *buf, const char *fmt, va_list args)
2336 const char *str = buf;
2344 unsigned long long u;
2350 /* skip any white space in format */
2351 /* white space in format matchs any amount of
2352 * white space, including none, in the input.
2354 if (isspace(*fmt)) {
2355 fmt = skip_spaces(++fmt);
2356 str = skip_spaces(str);
2359 /* anything that is not a conversion must match exactly */
2360 if (*fmt != '%' && *fmt) {
2361 if (*fmt++ != *str++)
2370 /* skip this conversion.
2371 * advance both strings to next white space
2376 while (!isspace(*fmt) && *fmt != '%' && *fmt)
2378 while (!isspace(*str) && *str)
2383 /* get field width */
2385 if (isdigit(*fmt)) {
2386 field_width = skip_atoi(&fmt);
2387 if (field_width <= 0)
2391 /* get conversion qualifier */
2393 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2394 _tolower(*fmt) == 'z') {
2396 if (unlikely(qualifier == *fmt)) {
2397 if (qualifier == 'h') {
2400 } else if (qualifier == 'l') {
2411 /* return number of characters read so far */
2412 *va_arg(args, int *) = str - buf;
2426 char *s = (char *)va_arg(args, char*);
2427 if (field_width == -1)
2431 } while (--field_width > 0 && *str);
2437 char *s = (char *)va_arg(args, char *);
2438 if (field_width == -1)
2439 field_width = SHRT_MAX;
2440 /* first, skip leading white space in buffer */
2441 str = skip_spaces(str);
2443 /* now copy until next white space */
2444 while (*str && !isspace(*str) && field_width--)
2464 /* looking for '%' in str */
2469 /* invalid format; stop here */
2473 /* have some sort of integer conversion.
2474 * first, skip white space in buffer.
2476 str = skip_spaces(str);
2479 if (is_sign && digit == '-')
2483 || (base == 16 && !isxdigit(digit))
2484 || (base == 10 && !isdigit(digit))
2485 || (base == 8 && (!isdigit(digit) || digit > '7'))
2486 || (base == 0 && !isdigit(digit)))
2490 val.s = qualifier != 'L' ?
2491 simple_strtol(str, &next, base) :
2492 simple_strtoll(str, &next, base);
2494 val.u = qualifier != 'L' ?
2495 simple_strtoul(str, &next, base) :
2496 simple_strtoull(str, &next, base);
2498 if (field_width > 0 && next - str > field_width) {
2500 _parse_integer_fixup_radix(str, &base);
2501 while (next - str > field_width) {
2503 val.s = div_s64(val.s, base);
2505 val.u = div_u64(val.u, base);
2510 switch (qualifier) {
2511 case 'H': /* that's 'hh' in format */
2513 *va_arg(args, signed char *) = val.s;
2515 *va_arg(args, unsigned char *) = val.u;
2519 *va_arg(args, short *) = val.s;
2521 *va_arg(args, unsigned short *) = val.u;
2525 *va_arg(args, long *) = val.s;
2527 *va_arg(args, unsigned long *) = val.u;
2531 *va_arg(args, long long *) = val.s;
2533 *va_arg(args, unsigned long long *) = val.u;
2537 *va_arg(args, size_t *) = val.u;
2541 *va_arg(args, int *) = val.s;
2543 *va_arg(args, unsigned int *) = val.u;
2555 EXPORT_SYMBOL(vsscanf);
2558 * sscanf - Unformat a buffer into a list of arguments
2559 * @buf: input buffer
2560 * @fmt: formatting of buffer
2561 * @...: resulting arguments
2563 int sscanf(const char *buf, const char *fmt, ...)
2568 va_start(args, fmt);
2569 i = vsscanf(buf, fmt, args);
2574 EXPORT_SYMBOL(sscanf);