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45 * This function is obsolete.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70 * This function is obsolete.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84 * This function is obsolete.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 SIGN 1 /* unsigned/signed, must be 1 */
344 #define LEFT 2 /* left justified */
345 #define PLUS 4 /* show plus */
346 #define SPACE 8 /* space if plus */
347 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
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 char tmp[3 * sizeof(num)];
389 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
391 bool is_zero = num == 0LL;
393 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
394 * produces same digits or (maybe lowercased) letters */
395 locase = (spec.flags & SMALL);
396 if (spec.flags & LEFT)
397 spec.flags &= ~ZEROPAD;
399 if (spec.flags & SIGN) {
400 if ((signed long long)num < 0) {
402 num = -(signed long long)num;
404 } else if (spec.flags & PLUS) {
407 } else if (spec.flags & SPACE) {
414 spec.field_width -= 2;
419 /* generate full string in tmp[], in reverse order */
422 tmp[i++] = hex_asc_upper[num] | locase;
423 else if (spec.base != 10) { /* 8 or 16 */
424 int mask = spec.base - 1;
430 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
433 } else { /* base 10 */
434 i = put_dec(tmp, num) - tmp;
437 /* printing 100 using %2d gives "100", not "00" */
438 if (i > spec.precision)
440 /* leading space padding */
441 spec.field_width -= spec.precision;
442 if (!(spec.flags & (ZEROPAD | LEFT))) {
443 while (--spec.field_width >= 0) {
455 /* "0x" / "0" prefix */
457 if (spec.base == 16 || !is_zero) {
462 if (spec.base == 16) {
464 *buf = ('X' | locase);
468 /* zero or space padding */
469 if (!(spec.flags & LEFT)) {
470 char c = ' ' + (spec.flags & ZEROPAD);
471 BUILD_BUG_ON(' ' + ZEROPAD != '0');
472 while (--spec.field_width >= 0) {
478 /* hmm even more zero padding? */
479 while (i <= --spec.precision) {
484 /* actual digits of result */
490 /* trailing space padding */
491 while (--spec.field_width >= 0) {
500 static noinline_for_stack
501 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
505 if ((unsigned long)s < PAGE_SIZE)
508 len = strnlen(s, spec.precision);
510 if (!(spec.flags & LEFT)) {
511 while (len < spec.field_width--) {
517 for (i = 0; i < len; ++i) {
522 while (len < spec.field_width--) {
531 static void widen(char *buf, char *end, unsigned len, unsigned spaces)
534 if (buf >= end) /* nowhere to put anything */
537 if (size <= spaces) {
538 memset(buf, ' ', size);
542 if (len > size - spaces)
544 memmove(buf + spaces, buf, len);
546 memset(buf, ' ', spaces);
549 static noinline_for_stack
550 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
553 const char *array[4], *s;
554 const struct dentry *p;
559 case '2': case '3': case '4':
560 depth = fmt[1] - '0';
567 for (i = 0; i < depth; i++, d = p) {
568 p = ACCESS_ONCE(d->d_parent);
569 array[i] = ACCESS_ONCE(d->d_name.name);
578 for (n = 0; n != spec.precision; n++, buf++) {
590 if (n < spec.field_width) {
591 /* we want to pad the sucker */
592 unsigned spaces = spec.field_width - n;
593 if (!(spec.flags & LEFT)) {
594 widen(buf - n, end, n, spaces);
606 static noinline_for_stack
607 char *symbol_string(char *buf, char *end, void *ptr,
608 struct printf_spec spec, const char *fmt)
611 #ifdef CONFIG_KALLSYMS
612 char sym[KSYM_SYMBOL_LEN];
616 ptr = __builtin_extract_return_addr(ptr);
617 value = (unsigned long)ptr;
619 #ifdef CONFIG_KALLSYMS
621 sprint_backtrace(sym, value);
622 else if (*fmt != 'f' && *fmt != 's')
623 sprint_symbol(sym, value);
625 sprint_symbol_no_offset(sym, value);
627 return string(buf, end, sym, spec);
629 spec.field_width = 2 * sizeof(void *);
630 spec.flags |= SPECIAL | SMALL | ZEROPAD;
633 return number(buf, end, value, spec);
637 static noinline_for_stack
638 char *resource_string(char *buf, char *end, struct resource *res,
639 struct printf_spec spec, const char *fmt)
641 #ifndef IO_RSRC_PRINTK_SIZE
642 #define IO_RSRC_PRINTK_SIZE 6
645 #ifndef MEM_RSRC_PRINTK_SIZE
646 #define MEM_RSRC_PRINTK_SIZE 10
648 static const struct printf_spec io_spec = {
650 .field_width = IO_RSRC_PRINTK_SIZE,
652 .flags = SPECIAL | SMALL | ZEROPAD,
654 static const struct printf_spec mem_spec = {
656 .field_width = MEM_RSRC_PRINTK_SIZE,
658 .flags = SPECIAL | SMALL | ZEROPAD,
660 static const struct printf_spec bus_spec = {
664 .flags = SMALL | ZEROPAD,
666 static const struct printf_spec dec_spec = {
671 static const struct printf_spec str_spec = {
676 static const struct printf_spec flag_spec = {
679 .flags = SPECIAL | SMALL,
682 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
683 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
684 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
685 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
686 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
687 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
688 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
689 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
691 char *p = sym, *pend = sym + sizeof(sym);
692 int decode = (fmt[0] == 'R') ? 1 : 0;
693 const struct printf_spec *specp;
696 if (res->flags & IORESOURCE_IO) {
697 p = string(p, pend, "io ", str_spec);
699 } else if (res->flags & IORESOURCE_MEM) {
700 p = string(p, pend, "mem ", str_spec);
702 } else if (res->flags & IORESOURCE_IRQ) {
703 p = string(p, pend, "irq ", str_spec);
705 } else if (res->flags & IORESOURCE_DMA) {
706 p = string(p, pend, "dma ", str_spec);
708 } else if (res->flags & IORESOURCE_BUS) {
709 p = string(p, pend, "bus ", str_spec);
712 p = string(p, pend, "??? ", str_spec);
716 if (decode && res->flags & IORESOURCE_UNSET) {
717 p = string(p, pend, "size ", str_spec);
718 p = number(p, pend, resource_size(res), *specp);
720 p = number(p, pend, res->start, *specp);
721 if (res->start != res->end) {
723 p = number(p, pend, res->end, *specp);
727 if (res->flags & IORESOURCE_MEM_64)
728 p = string(p, pend, " 64bit", str_spec);
729 if (res->flags & IORESOURCE_PREFETCH)
730 p = string(p, pend, " pref", str_spec);
731 if (res->flags & IORESOURCE_WINDOW)
732 p = string(p, pend, " window", str_spec);
733 if (res->flags & IORESOURCE_DISABLED)
734 p = string(p, pend, " disabled", str_spec);
736 p = string(p, pend, " flags ", str_spec);
737 p = number(p, pend, res->flags, flag_spec);
742 return string(buf, end, sym, spec);
745 static noinline_for_stack
746 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
749 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
750 negative value, fallback to the default */
753 if (spec.field_width == 0)
754 /* nothing to print */
757 if (ZERO_OR_NULL_PTR(addr))
759 return string(buf, end, NULL, spec);
776 if (spec.field_width > 0)
777 len = min_t(int, spec.field_width, 64);
779 for (i = 0; i < len && buf < end - 1; i++) {
780 buf = hex_byte_pack(buf, addr[i]);
782 if (buf < end && separator && i != len - 1)
789 static noinline_for_stack
790 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
791 struct printf_spec spec, const char *fmt)
793 const int CHUNKSZ = 32;
794 int nr_bits = max_t(int, spec.field_width, 0);
798 /* reused to print numbers */
799 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
801 chunksz = nr_bits & (CHUNKSZ - 1);
805 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
806 for (; i >= 0; i -= CHUNKSZ) {
810 chunkmask = ((1ULL << chunksz) - 1);
811 word = i / BITS_PER_LONG;
812 bit = i % BITS_PER_LONG;
813 val = (bitmap[word] >> bit) & chunkmask;
822 spec.field_width = DIV_ROUND_UP(chunksz, 4);
823 buf = number(buf, end, val, spec);
830 static noinline_for_stack
831 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
832 struct printf_spec spec, const char *fmt)
834 int nr_bits = max_t(int, spec.field_width, 0);
835 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
839 /* reused to print numbers */
840 spec = (struct printf_spec){ .base = 10 };
842 rbot = cur = find_first_bit(bitmap, nr_bits);
843 while (cur < nr_bits) {
845 cur = find_next_bit(bitmap, nr_bits, cur + 1);
846 if (cur < nr_bits && cur <= rtop + 1)
856 buf = number(buf, end, rbot, spec);
862 buf = number(buf, end, rtop, spec);
870 static noinline_for_stack
871 char *mac_address_string(char *buf, char *end, u8 *addr,
872 struct printf_spec spec, const char *fmt)
874 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
878 bool reversed = false;
894 for (i = 0; i < 6; i++) {
896 p = hex_byte_pack(p, addr[5 - i]);
898 p = hex_byte_pack(p, addr[i]);
900 if (fmt[0] == 'M' && i != 5)
905 return string(buf, end, mac_addr, spec);
908 static noinline_for_stack
909 char *ip4_string(char *p, const u8 *addr, const char *fmt)
912 bool leading_zeros = (fmt[0] == 'i');
937 for (i = 0; i < 4; i++) {
938 char temp[3]; /* hold each IP quad in reverse order */
939 int digits = put_dec_trunc8(temp, addr[index]) - temp;
946 /* reverse the digits in the quad */
958 static noinline_for_stack
959 char *ip6_compressed_string(char *p, const char *addr)
962 unsigned char zerolength[8];
967 bool needcolon = false;
971 memcpy(&in6, addr, sizeof(struct in6_addr));
973 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
975 memset(zerolength, 0, sizeof(zerolength));
982 /* find position of longest 0 run */
983 for (i = 0; i < range; i++) {
984 for (j = i; j < range; j++) {
985 if (in6.s6_addr16[j] != 0)
990 for (i = 0; i < range; i++) {
991 if (zerolength[i] > longest) {
992 longest = zerolength[i];
996 if (longest == 1) /* don't compress a single 0 */
1000 for (i = 0; i < range; i++) {
1001 if (i == colonpos) {
1002 if (needcolon || i == 0)
1013 /* hex u16 without leading 0s */
1014 word = ntohs(in6.s6_addr16[i]);
1019 p = hex_byte_pack(p, hi);
1021 *p++ = hex_asc_lo(hi);
1022 p = hex_byte_pack(p, lo);
1025 p = hex_byte_pack(p, lo);
1027 *p++ = hex_asc_lo(lo);
1034 p = ip4_string(p, &in6.s6_addr[12], "I4");
1041 static noinline_for_stack
1042 char *ip6_string(char *p, const char *addr, const char *fmt)
1046 for (i = 0; i < 8; i++) {
1047 p = hex_byte_pack(p, *addr++);
1048 p = hex_byte_pack(p, *addr++);
1049 if (fmt[0] == 'I' && i != 7)
1057 static noinline_for_stack
1058 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1059 struct printf_spec spec, const char *fmt)
1061 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1063 if (fmt[0] == 'I' && fmt[2] == 'c')
1064 ip6_compressed_string(ip6_addr, addr);
1066 ip6_string(ip6_addr, addr, fmt);
1068 return string(buf, end, ip6_addr, spec);
1071 static noinline_for_stack
1072 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1073 struct printf_spec spec, const char *fmt)
1075 char ip4_addr[sizeof("255.255.255.255")];
1077 ip4_string(ip4_addr, addr, fmt);
1079 return string(buf, end, ip4_addr, spec);
1082 static noinline_for_stack
1083 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1084 struct printf_spec spec, const char *fmt)
1086 bool have_p = false, have_s = false, have_f = false, have_c = false;
1087 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1088 sizeof(":12345") + sizeof("/123456789") +
1089 sizeof("%1234567890")];
1090 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1091 const u8 *addr = (const u8 *) &sa->sin6_addr;
1092 char fmt6[2] = { fmt[0], '6' };
1096 while (isalpha(*++fmt)) {
1113 if (have_p || have_s || have_f) {
1118 if (fmt6[0] == 'I' && have_c)
1119 p = ip6_compressed_string(ip6_addr + off, addr);
1121 p = ip6_string(ip6_addr + off, addr, fmt6);
1123 if (have_p || have_s || have_f)
1128 p = number(p, pend, ntohs(sa->sin6_port), spec);
1132 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1133 IPV6_FLOWINFO_MASK), spec);
1137 p = number(p, pend, sa->sin6_scope_id, spec);
1141 return string(buf, end, ip6_addr, spec);
1144 static noinline_for_stack
1145 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1146 struct printf_spec spec, const char *fmt)
1148 bool have_p = false;
1149 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1150 char *pend = ip4_addr + sizeof(ip4_addr);
1151 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1152 char fmt4[3] = { fmt[0], '4', 0 };
1155 while (isalpha(*++fmt)) {
1169 p = ip4_string(ip4_addr, addr, fmt4);
1172 p = number(p, pend, ntohs(sa->sin_port), spec);
1176 return string(buf, end, ip4_addr, spec);
1179 static noinline_for_stack
1180 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1185 unsigned int flags = 0;
1188 if (spec.field_width == 0)
1189 return buf; /* nothing to print */
1191 if (ZERO_OR_NULL_PTR(addr))
1192 return string(buf, end, NULL, spec); /* NULL pointer */
1196 switch (fmt[count++]) {
1198 flags |= ESCAPE_ANY;
1201 flags |= ESCAPE_SPECIAL;
1204 flags |= ESCAPE_HEX;
1207 flags |= ESCAPE_NULL;
1210 flags |= ESCAPE_OCTAL;
1216 flags |= ESCAPE_SPACE;
1225 flags = ESCAPE_ANY_NP;
1227 len = spec.field_width < 0 ? 1 : spec.field_width;
1229 /* Ignore the error. We print as many characters as we can */
1230 string_escape_mem(addr, len, &buf, end - buf, flags, NULL);
1235 static noinline_for_stack
1236 char *uuid_string(char *buf, char *end, const u8 *addr,
1237 struct printf_spec spec, const char *fmt)
1239 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1242 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1243 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1244 const u8 *index = be;
1249 uc = true; /* fall-through */
1258 for (i = 0; i < 16; i++) {
1259 p = hex_byte_pack(p, addr[index[i]]);
1279 return string(buf, end, uuid, spec);
1283 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
1284 struct printf_spec spec)
1286 spec.flags |= SPECIAL | SMALL | ZEROPAD;
1287 if (spec.field_width == -1)
1288 spec.field_width = 2 + 2 * sizeof(netdev_features_t);
1291 return number(buf, end, *(const netdev_features_t *)addr, spec);
1294 static noinline_for_stack
1295 char *address_val(char *buf, char *end, const void *addr,
1296 struct printf_spec spec, const char *fmt)
1298 unsigned long long num;
1300 spec.flags |= SPECIAL | SMALL | ZEROPAD;
1305 num = *(const dma_addr_t *)addr;
1306 spec.field_width = sizeof(dma_addr_t) * 2 + 2;
1310 num = *(const phys_addr_t *)addr;
1311 spec.field_width = sizeof(phys_addr_t) * 2 + 2;
1315 return number(buf, end, num, spec);
1318 int kptr_restrict __read_mostly;
1321 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1322 * by an extra set of alphanumeric characters that are extended format
1325 * Right now we handle:
1327 * - 'F' For symbolic function descriptor pointers with offset
1328 * - 'f' For simple symbolic function names without offset
1329 * - 'S' For symbolic direct pointers with offset
1330 * - 's' For symbolic direct pointers without offset
1331 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1332 * - 'B' For backtraced symbolic direct pointers with offset
1333 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1334 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1335 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1336 * width which must be explicitly specified either as part of the
1337 * format string '%32b[l]' or through '%*b[l]', [l] selects
1338 * range-list format instead of hex format
1339 * - 'M' For a 6-byte MAC address, it prints the address in the
1340 * usual colon-separated hex notation
1341 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1342 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1343 * with a dash-separated hex notation
1344 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1345 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1346 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1347 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1349 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1350 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1351 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1352 * IPv6 omits the colons (01020304...0f)
1353 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1355 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1356 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1357 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1358 * - 'I[6S]c' for IPv6 addresses printed as specified by
1359 * http://tools.ietf.org/html/rfc5952
1360 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1361 * of the following flags (see string_escape_mem() for the
1364 * c - ESCAPE_SPECIAL
1370 * By default ESCAPE_ANY_NP is used.
1371 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1372 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1373 * Options for %pU are:
1374 * b big endian lower case hex (default)
1375 * B big endian UPPER case hex
1376 * l little endian lower case hex
1377 * L little endian UPPER case hex
1378 * big endian output byte order is:
1379 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1380 * little endian output byte order is:
1381 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1382 * - 'V' For a struct va_format which contains a format string * and va_list *,
1383 * call vsnprintf(->format, *->va_list).
1384 * Implements a "recursive vsnprintf".
1385 * Do not use this feature without some mechanism to verify the
1386 * correctness of the format string and va_list arguments.
1387 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1388 * - 'NF' For a netdev_features_t
1389 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1390 * a certain separator (' ' by default):
1394 * The maximum supported length is 64 bytes of the input. Consider
1395 * to use print_hex_dump() for the larger input.
1396 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1397 * (default assumed to be phys_addr_t, passed by reference)
1398 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1399 * - 'D[234]' Same as 'd' but for a struct file
1401 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1402 * function pointers are really function descriptors, which contain a
1403 * pointer to the real address.
1405 static noinline_for_stack
1406 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1407 struct printf_spec spec)
1409 int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
1411 if (!ptr && *fmt != 'K') {
1413 * Print (null) with the same width as a pointer so it makes
1414 * tabular output look nice.
1416 if (spec.field_width == -1)
1417 spec.field_width = default_width;
1418 return string(buf, end, "(null)", spec);
1424 ptr = dereference_function_descriptor(ptr);
1429 return symbol_string(buf, end, ptr, spec, fmt);
1432 return resource_string(buf, end, ptr, spec, fmt);
1434 return hex_string(buf, end, ptr, spec, fmt);
1438 return bitmap_list_string(buf, end, ptr, spec, fmt);
1440 return bitmap_string(buf, end, ptr, spec, fmt);
1442 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1443 case 'm': /* Contiguous: 000102030405 */
1445 /* [mM]R (Reverse order; Bluetooth) */
1446 return mac_address_string(buf, end, ptr, spec, fmt);
1447 case 'I': /* Formatted IP supported
1449 * 6: 0001:0203:...:0708
1450 * 6c: 1::708 or 1::1.2.3.4
1452 case 'i': /* Contiguous:
1453 * 4: 001.002.003.004
1458 return ip6_addr_string(buf, end, ptr, spec, fmt);
1460 return ip4_addr_string(buf, end, ptr, spec, fmt);
1463 struct sockaddr raw;
1464 struct sockaddr_in v4;
1465 struct sockaddr_in6 v6;
1468 switch (sa->raw.sa_family) {
1470 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1472 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1474 return string(buf, end, "(invalid address)", spec);
1479 return escaped_string(buf, end, ptr, spec, fmt);
1481 return uuid_string(buf, end, ptr, spec, fmt);
1486 va_copy(va, *((struct va_format *)ptr)->va);
1487 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1488 ((struct va_format *)ptr)->fmt, va);
1494 * %pK cannot be used in IRQ context because its test
1495 * for CAP_SYSLOG would be meaningless.
1497 if (kptr_restrict && (in_irq() || in_serving_softirq() ||
1499 if (spec.field_width == -1)
1500 spec.field_width = default_width;
1501 return string(buf, end, "pK-error", spec);
1504 switch (kptr_restrict) {
1506 /* Always print %pK values */
1510 * Only print the real pointer value if the current
1511 * process has CAP_SYSLOG and is running with the
1512 * same credentials it started with. This is because
1513 * access to files is checked at open() time, but %pK
1514 * checks permission at read() time. We don't want to
1515 * leak pointer values if a binary opens a file using
1516 * %pK and then elevates privileges before reading it.
1518 const struct cred *cred = current_cred();
1520 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1521 !uid_eq(cred->euid, cred->uid) ||
1522 !gid_eq(cred->egid, cred->gid))
1528 /* Always print 0's for %pK */
1537 return netdev_feature_string(buf, end, ptr, spec);
1541 return address_val(buf, end, ptr, spec, fmt);
1543 return dentry_name(buf, end, ptr, spec, fmt);
1545 return dentry_name(buf, end,
1546 ((const struct file *)ptr)->f_path.dentry,
1549 spec.flags |= SMALL;
1550 if (spec.field_width == -1) {
1551 spec.field_width = default_width;
1552 spec.flags |= ZEROPAD;
1556 return number(buf, end, (unsigned long) ptr, spec);
1560 * Helper function to decode printf style format.
1561 * Each call decode a token from the format and return the
1562 * number of characters read (or likely the delta where it wants
1563 * to go on the next call).
1564 * The decoded token is returned through the parameters
1566 * 'h', 'l', or 'L' for integer fields
1567 * 'z' support added 23/7/1999 S.H.
1568 * 'z' changed to 'Z' --davidm 1/25/99
1569 * 't' added for ptrdiff_t
1571 * @fmt: the format string
1572 * @type of the token returned
1573 * @flags: various flags such as +, -, # tokens..
1574 * @field_width: overwritten width
1575 * @base: base of the number (octal, hex, ...)
1576 * @precision: precision of a number
1577 * @qualifier: qualifier of a number (long, size_t, ...)
1579 static noinline_for_stack
1580 int format_decode(const char *fmt, struct printf_spec *spec)
1582 const char *start = fmt;
1584 /* we finished early by reading the field width */
1585 if (spec->type == FORMAT_TYPE_WIDTH) {
1586 if (spec->field_width < 0) {
1587 spec->field_width = -spec->field_width;
1588 spec->flags |= LEFT;
1590 spec->type = FORMAT_TYPE_NONE;
1594 /* we finished early by reading the precision */
1595 if (spec->type == FORMAT_TYPE_PRECISION) {
1596 if (spec->precision < 0)
1597 spec->precision = 0;
1599 spec->type = FORMAT_TYPE_NONE;
1604 spec->type = FORMAT_TYPE_NONE;
1606 for (; *fmt ; ++fmt) {
1611 /* Return the current non-format string */
1612 if (fmt != start || !*fmt)
1618 while (1) { /* this also skips first '%' */
1624 case '-': spec->flags |= LEFT; break;
1625 case '+': spec->flags |= PLUS; break;
1626 case ' ': spec->flags |= SPACE; break;
1627 case '#': spec->flags |= SPECIAL; break;
1628 case '0': spec->flags |= ZEROPAD; break;
1629 default: found = false;
1636 /* get field width */
1637 spec->field_width = -1;
1640 spec->field_width = skip_atoi(&fmt);
1641 else if (*fmt == '*') {
1642 /* it's the next argument */
1643 spec->type = FORMAT_TYPE_WIDTH;
1644 return ++fmt - start;
1648 /* get the precision */
1649 spec->precision = -1;
1652 if (isdigit(*fmt)) {
1653 spec->precision = skip_atoi(&fmt);
1654 if (spec->precision < 0)
1655 spec->precision = 0;
1656 } else if (*fmt == '*') {
1657 /* it's the next argument */
1658 spec->type = FORMAT_TYPE_PRECISION;
1659 return ++fmt - start;
1664 /* get the conversion qualifier */
1665 spec->qualifier = -1;
1666 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1667 _tolower(*fmt) == 'z' || *fmt == 't') {
1668 spec->qualifier = *fmt++;
1669 if (unlikely(spec->qualifier == *fmt)) {
1670 if (spec->qualifier == 'l') {
1671 spec->qualifier = 'L';
1673 } else if (spec->qualifier == 'h') {
1674 spec->qualifier = 'H';
1684 spec->type = FORMAT_TYPE_CHAR;
1685 return ++fmt - start;
1688 spec->type = FORMAT_TYPE_STR;
1689 return ++fmt - start;
1692 spec->type = FORMAT_TYPE_PTR;
1693 return ++fmt - start;
1696 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1697 return ++fmt - start;
1699 /* integer number formats - set up the flags and "break" */
1705 spec->flags |= SMALL;
1713 spec->flags |= SIGN;
1719 * Since %n poses a greater security risk than utility, treat
1720 * it as an invalid format specifier. Warn about its use so
1721 * that new instances don't get added.
1723 WARN_ONCE(1, "Please remove ignored %%n in '%s'\n", fmt);
1727 spec->type = FORMAT_TYPE_INVALID;
1731 if (spec->qualifier == 'L')
1732 spec->type = FORMAT_TYPE_LONG_LONG;
1733 else if (spec->qualifier == 'l') {
1734 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1735 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1736 } else if (_tolower(spec->qualifier) == 'z') {
1737 spec->type = FORMAT_TYPE_SIZE_T;
1738 } else if (spec->qualifier == 't') {
1739 spec->type = FORMAT_TYPE_PTRDIFF;
1740 } else if (spec->qualifier == 'H') {
1741 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1742 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1743 } else if (spec->qualifier == 'h') {
1744 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1745 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1747 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1748 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1751 return ++fmt - start;
1755 * vsnprintf - Format a string and place it in a buffer
1756 * @buf: The buffer to place the result into
1757 * @size: The size of the buffer, including the trailing null space
1758 * @fmt: The format string to use
1759 * @args: Arguments for the format string
1761 * This function follows C99 vsnprintf, but has some extensions:
1762 * %pS output the name of a text symbol with offset
1763 * %ps output the name of a text symbol without offset
1764 * %pF output the name of a function pointer with its offset
1765 * %pf output the name of a function pointer without its offset
1766 * %pB output the name of a backtrace symbol with its offset
1767 * %pR output the address range in a struct resource with decoded flags
1768 * %pr output the address range in a struct resource with raw flags
1769 * %pb output the bitmap with field width as the number of bits
1770 * %pbl output the bitmap as range list with field width as the number of bits
1771 * %pM output a 6-byte MAC address with colons
1772 * %pMR output a 6-byte MAC address with colons in reversed order
1773 * %pMF output a 6-byte MAC address with dashes
1774 * %pm output a 6-byte MAC address without colons
1775 * %pmR output a 6-byte MAC address without colons in reversed order
1776 * %pI4 print an IPv4 address without leading zeros
1777 * %pi4 print an IPv4 address with leading zeros
1778 * %pI6 print an IPv6 address with colons
1779 * %pi6 print an IPv6 address without colons
1780 * %pI6c print an IPv6 address as specified by RFC 5952
1781 * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1782 * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address
1783 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1785 * %*pE[achnops] print an escaped buffer
1786 * %*ph[CDN] a variable-length hex string with a separator (supports up to 64
1787 * bytes of the input)
1790 * ** Please update Documentation/printk-formats.txt when making changes **
1792 * The return value is the number of characters which would
1793 * be generated for the given input, excluding the trailing
1794 * '\0', as per ISO C99. If you want to have the exact
1795 * number of characters written into @buf as return value
1796 * (not including the trailing '\0'), use vscnprintf(). If the
1797 * return is greater than or equal to @size, the resulting
1798 * string is truncated.
1800 * If you're not already dealing with a va_list consider using snprintf().
1802 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1804 unsigned long long num;
1806 struct printf_spec spec = {0};
1808 /* Reject out-of-range values early. Large positive sizes are
1809 used for unknown buffer sizes. */
1810 if (WARN_ON_ONCE(size > INT_MAX))
1816 /* Make sure end is always >= buf */
1823 const char *old_fmt = fmt;
1824 int read = format_decode(fmt, &spec);
1828 switch (spec.type) {
1829 case FORMAT_TYPE_NONE: {
1832 if (copy > end - str)
1834 memcpy(str, old_fmt, copy);
1840 case FORMAT_TYPE_WIDTH:
1841 spec.field_width = va_arg(args, int);
1844 case FORMAT_TYPE_PRECISION:
1845 spec.precision = va_arg(args, int);
1848 case FORMAT_TYPE_CHAR: {
1851 if (!(spec.flags & LEFT)) {
1852 while (--spec.field_width > 0) {
1859 c = (unsigned char) va_arg(args, int);
1863 while (--spec.field_width > 0) {
1871 case FORMAT_TYPE_STR:
1872 str = string(str, end, va_arg(args, char *), spec);
1875 case FORMAT_TYPE_PTR:
1876 str = pointer(fmt, str, end, va_arg(args, void *),
1878 while (isalnum(*fmt))
1882 case FORMAT_TYPE_PERCENT_CHAR:
1888 case FORMAT_TYPE_INVALID:
1895 switch (spec.type) {
1896 case FORMAT_TYPE_LONG_LONG:
1897 num = va_arg(args, long long);
1899 case FORMAT_TYPE_ULONG:
1900 num = va_arg(args, unsigned long);
1902 case FORMAT_TYPE_LONG:
1903 num = va_arg(args, long);
1905 case FORMAT_TYPE_SIZE_T:
1906 if (spec.flags & SIGN)
1907 num = va_arg(args, ssize_t);
1909 num = va_arg(args, size_t);
1911 case FORMAT_TYPE_PTRDIFF:
1912 num = va_arg(args, ptrdiff_t);
1914 case FORMAT_TYPE_UBYTE:
1915 num = (unsigned char) va_arg(args, int);
1917 case FORMAT_TYPE_BYTE:
1918 num = (signed char) va_arg(args, int);
1920 case FORMAT_TYPE_USHORT:
1921 num = (unsigned short) va_arg(args, int);
1923 case FORMAT_TYPE_SHORT:
1924 num = (short) va_arg(args, int);
1926 case FORMAT_TYPE_INT:
1927 num = (int) va_arg(args, int);
1930 num = va_arg(args, unsigned int);
1933 str = number(str, end, num, spec);
1944 /* the trailing null byte doesn't count towards the total */
1948 EXPORT_SYMBOL(vsnprintf);
1951 * vscnprintf - Format a string and place it in a buffer
1952 * @buf: The buffer to place the result into
1953 * @size: The size of the buffer, including the trailing null space
1954 * @fmt: The format string to use
1955 * @args: Arguments for the format string
1957 * The return value is the number of characters which have been written into
1958 * the @buf not including the trailing '\0'. If @size is == 0 the function
1961 * If you're not already dealing with a va_list consider using scnprintf().
1963 * See the vsnprintf() documentation for format string extensions over C99.
1965 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1969 i = vsnprintf(buf, size, fmt, args);
1971 if (likely(i < size))
1977 EXPORT_SYMBOL(vscnprintf);
1980 * snprintf - Format a string and place it in a buffer
1981 * @buf: The buffer to place the result into
1982 * @size: The size of the buffer, including the trailing null space
1983 * @fmt: The format string to use
1984 * @...: Arguments for the format string
1986 * The return value is the number of characters which would be
1987 * generated for the given input, excluding the trailing null,
1988 * as per ISO C99. If the return is greater than or equal to
1989 * @size, the resulting string is truncated.
1991 * See the vsnprintf() documentation for format string extensions over C99.
1993 int snprintf(char *buf, size_t size, const char *fmt, ...)
1998 va_start(args, fmt);
1999 i = vsnprintf(buf, size, fmt, args);
2004 EXPORT_SYMBOL(snprintf);
2007 * scnprintf - Format a string and place it in a buffer
2008 * @buf: The buffer to place the result into
2009 * @size: The size of the buffer, including the trailing null space
2010 * @fmt: The format string to use
2011 * @...: Arguments for the format string
2013 * The return value is the number of characters written into @buf not including
2014 * the trailing '\0'. If @size is == 0 the function returns 0.
2017 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2022 va_start(args, fmt);
2023 i = vscnprintf(buf, size, fmt, args);
2028 EXPORT_SYMBOL(scnprintf);
2031 * vsprintf - Format a string and place it in a buffer
2032 * @buf: The buffer to place the result into
2033 * @fmt: The format string to use
2034 * @args: Arguments for the format string
2036 * The function returns the number of characters written
2037 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2040 * If you're not already dealing with a va_list consider using sprintf().
2042 * See the vsnprintf() documentation for format string extensions over C99.
2044 int vsprintf(char *buf, const char *fmt, va_list args)
2046 return vsnprintf(buf, INT_MAX, fmt, args);
2048 EXPORT_SYMBOL(vsprintf);
2051 * sprintf - Format a string and place it in a buffer
2052 * @buf: The buffer to place the result into
2053 * @fmt: The format string to use
2054 * @...: Arguments for the format string
2056 * The function returns the number of characters written
2057 * into @buf. Use snprintf() or scnprintf() in order to avoid
2060 * See the vsnprintf() documentation for format string extensions over C99.
2062 int sprintf(char *buf, const char *fmt, ...)
2067 va_start(args, fmt);
2068 i = vsnprintf(buf, INT_MAX, fmt, args);
2073 EXPORT_SYMBOL(sprintf);
2075 #ifdef CONFIG_BINARY_PRINTF
2078 * vbin_printf() - VA arguments to binary data
2079 * bstr_printf() - Binary data to text string
2083 * vbin_printf - Parse a format string and place args' binary value in a buffer
2084 * @bin_buf: The buffer to place args' binary value
2085 * @size: The size of the buffer(by words(32bits), not characters)
2086 * @fmt: The format string to use
2087 * @args: Arguments for the format string
2089 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2092 * The return value is the number of words(32bits) which would be generated for
2096 * If the return value is greater than @size, the resulting bin_buf is NOT
2097 * valid for bstr_printf().
2099 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2101 struct printf_spec spec = {0};
2104 str = (char *)bin_buf;
2105 end = (char *)(bin_buf + size);
2107 #define save_arg(type) \
2109 if (sizeof(type) == 8) { \
2110 unsigned long long value; \
2111 str = PTR_ALIGN(str, sizeof(u32)); \
2112 value = va_arg(args, unsigned long long); \
2113 if (str + sizeof(type) <= end) { \
2114 *(u32 *)str = *(u32 *)&value; \
2115 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2118 unsigned long value; \
2119 str = PTR_ALIGN(str, sizeof(type)); \
2120 value = va_arg(args, int); \
2121 if (str + sizeof(type) <= end) \
2122 *(typeof(type) *)str = (type)value; \
2124 str += sizeof(type); \
2128 int read = format_decode(fmt, &spec);
2132 switch (spec.type) {
2133 case FORMAT_TYPE_NONE:
2134 case FORMAT_TYPE_INVALID:
2135 case FORMAT_TYPE_PERCENT_CHAR:
2138 case FORMAT_TYPE_WIDTH:
2139 case FORMAT_TYPE_PRECISION:
2143 case FORMAT_TYPE_CHAR:
2147 case FORMAT_TYPE_STR: {
2148 const char *save_str = va_arg(args, char *);
2151 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2152 || (unsigned long)save_str < PAGE_SIZE)
2153 save_str = "(null)";
2154 len = strlen(save_str) + 1;
2155 if (str + len < end)
2156 memcpy(str, save_str, len);
2161 case FORMAT_TYPE_PTR:
2163 /* skip all alphanumeric pointer suffixes */
2164 while (isalnum(*fmt))
2169 switch (spec.type) {
2171 case FORMAT_TYPE_LONG_LONG:
2172 save_arg(long long);
2174 case FORMAT_TYPE_ULONG:
2175 case FORMAT_TYPE_LONG:
2176 save_arg(unsigned long);
2178 case FORMAT_TYPE_SIZE_T:
2181 case FORMAT_TYPE_PTRDIFF:
2182 save_arg(ptrdiff_t);
2184 case FORMAT_TYPE_UBYTE:
2185 case FORMAT_TYPE_BYTE:
2188 case FORMAT_TYPE_USHORT:
2189 case FORMAT_TYPE_SHORT:
2198 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2201 EXPORT_SYMBOL_GPL(vbin_printf);
2204 * bstr_printf - Format a string from binary arguments and place it in a buffer
2205 * @buf: The buffer to place the result into
2206 * @size: The size of the buffer, including the trailing null space
2207 * @fmt: The format string to use
2208 * @bin_buf: Binary arguments for the format string
2210 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2211 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2212 * a binary buffer that generated by vbin_printf.
2214 * The format follows C99 vsnprintf, but has some extensions:
2215 * see vsnprintf comment for details.
2217 * The return value is the number of characters which would
2218 * be generated for the given input, excluding the trailing
2219 * '\0', as per ISO C99. If you want to have the exact
2220 * number of characters written into @buf as return value
2221 * (not including the trailing '\0'), use vscnprintf(). If the
2222 * return is greater than or equal to @size, the resulting
2223 * string is truncated.
2225 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2227 struct printf_spec spec = {0};
2229 const char *args = (const char *)bin_buf;
2231 if (WARN_ON_ONCE((int) size < 0))
2237 #define get_arg(type) \
2239 typeof(type) value; \
2240 if (sizeof(type) == 8) { \
2241 args = PTR_ALIGN(args, sizeof(u32)); \
2242 *(u32 *)&value = *(u32 *)args; \
2243 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2245 args = PTR_ALIGN(args, sizeof(type)); \
2246 value = *(typeof(type) *)args; \
2248 args += sizeof(type); \
2252 /* Make sure end is always >= buf */
2259 const char *old_fmt = fmt;
2260 int read = format_decode(fmt, &spec);
2264 switch (spec.type) {
2265 case FORMAT_TYPE_NONE: {
2268 if (copy > end - str)
2270 memcpy(str, old_fmt, copy);
2276 case FORMAT_TYPE_WIDTH:
2277 spec.field_width = get_arg(int);
2280 case FORMAT_TYPE_PRECISION:
2281 spec.precision = get_arg(int);
2284 case FORMAT_TYPE_CHAR: {
2287 if (!(spec.flags & LEFT)) {
2288 while (--spec.field_width > 0) {
2294 c = (unsigned char) get_arg(char);
2298 while (--spec.field_width > 0) {
2306 case FORMAT_TYPE_STR: {
2307 const char *str_arg = args;
2308 args += strlen(str_arg) + 1;
2309 str = string(str, end, (char *)str_arg, spec);
2313 case FORMAT_TYPE_PTR:
2314 str = pointer(fmt, str, end, get_arg(void *), spec);
2315 while (isalnum(*fmt))
2319 case FORMAT_TYPE_PERCENT_CHAR:
2320 case FORMAT_TYPE_INVALID:
2327 unsigned long long num;
2329 switch (spec.type) {
2331 case FORMAT_TYPE_LONG_LONG:
2332 num = get_arg(long long);
2334 case FORMAT_TYPE_ULONG:
2335 case FORMAT_TYPE_LONG:
2336 num = get_arg(unsigned long);
2338 case FORMAT_TYPE_SIZE_T:
2339 num = get_arg(size_t);
2341 case FORMAT_TYPE_PTRDIFF:
2342 num = get_arg(ptrdiff_t);
2344 case FORMAT_TYPE_UBYTE:
2345 num = get_arg(unsigned char);
2347 case FORMAT_TYPE_BYTE:
2348 num = get_arg(signed char);
2350 case FORMAT_TYPE_USHORT:
2351 num = get_arg(unsigned short);
2353 case FORMAT_TYPE_SHORT:
2354 num = get_arg(short);
2356 case FORMAT_TYPE_UINT:
2357 num = get_arg(unsigned int);
2363 str = number(str, end, num, spec);
2365 } /* switch(spec.type) */
2377 /* the trailing null byte doesn't count towards the total */
2380 EXPORT_SYMBOL_GPL(bstr_printf);
2383 * bprintf - Parse a format string and place args' binary value in a buffer
2384 * @bin_buf: The buffer to place args' binary value
2385 * @size: The size of the buffer(by words(32bits), not characters)
2386 * @fmt: The format string to use
2387 * @...: Arguments for the format string
2389 * The function returns the number of words(u32) written
2392 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2397 va_start(args, fmt);
2398 ret = vbin_printf(bin_buf, size, fmt, args);
2403 EXPORT_SYMBOL_GPL(bprintf);
2405 #endif /* CONFIG_BINARY_PRINTF */
2408 * vsscanf - Unformat a buffer into a list of arguments
2409 * @buf: input buffer
2410 * @fmt: format of buffer
2413 int vsscanf(const char *buf, const char *fmt, va_list args)
2415 const char *str = buf;
2423 unsigned long long u;
2429 /* skip any white space in format */
2430 /* white space in format matchs any amount of
2431 * white space, including none, in the input.
2433 if (isspace(*fmt)) {
2434 fmt = skip_spaces(++fmt);
2435 str = skip_spaces(str);
2438 /* anything that is not a conversion must match exactly */
2439 if (*fmt != '%' && *fmt) {
2440 if (*fmt++ != *str++)
2449 /* skip this conversion.
2450 * advance both strings to next white space
2455 while (!isspace(*fmt) && *fmt != '%' && *fmt)
2457 while (!isspace(*str) && *str)
2462 /* get field width */
2464 if (isdigit(*fmt)) {
2465 field_width = skip_atoi(&fmt);
2466 if (field_width <= 0)
2470 /* get conversion qualifier */
2472 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2473 _tolower(*fmt) == 'z') {
2475 if (unlikely(qualifier == *fmt)) {
2476 if (qualifier == 'h') {
2479 } else if (qualifier == 'l') {
2490 /* return number of characters read so far */
2491 *va_arg(args, int *) = str - buf;
2505 char *s = (char *)va_arg(args, char*);
2506 if (field_width == -1)
2510 } while (--field_width > 0 && *str);
2516 char *s = (char *)va_arg(args, char *);
2517 if (field_width == -1)
2518 field_width = SHRT_MAX;
2519 /* first, skip leading white space in buffer */
2520 str = skip_spaces(str);
2522 /* now copy until next white space */
2523 while (*str && !isspace(*str) && field_width--)
2543 /* looking for '%' in str */
2548 /* invalid format; stop here */
2552 /* have some sort of integer conversion.
2553 * first, skip white space in buffer.
2555 str = skip_spaces(str);
2558 if (is_sign && digit == '-')
2562 || (base == 16 && !isxdigit(digit))
2563 || (base == 10 && !isdigit(digit))
2564 || (base == 8 && (!isdigit(digit) || digit > '7'))
2565 || (base == 0 && !isdigit(digit)))
2569 val.s = qualifier != 'L' ?
2570 simple_strtol(str, &next, base) :
2571 simple_strtoll(str, &next, base);
2573 val.u = qualifier != 'L' ?
2574 simple_strtoul(str, &next, base) :
2575 simple_strtoull(str, &next, base);
2577 if (field_width > 0 && next - str > field_width) {
2579 _parse_integer_fixup_radix(str, &base);
2580 while (next - str > field_width) {
2582 val.s = div_s64(val.s, base);
2584 val.u = div_u64(val.u, base);
2589 switch (qualifier) {
2590 case 'H': /* that's 'hh' in format */
2592 *va_arg(args, signed char *) = val.s;
2594 *va_arg(args, unsigned char *) = val.u;
2598 *va_arg(args, short *) = val.s;
2600 *va_arg(args, unsigned short *) = val.u;
2604 *va_arg(args, long *) = val.s;
2606 *va_arg(args, unsigned long *) = val.u;
2610 *va_arg(args, long long *) = val.s;
2612 *va_arg(args, unsigned long long *) = val.u;
2616 *va_arg(args, size_t *) = val.u;
2620 *va_arg(args, int *) = val.s;
2622 *va_arg(args, unsigned int *) = val.u;
2634 EXPORT_SYMBOL(vsscanf);
2637 * sscanf - Unformat a buffer into a list of arguments
2638 * @buf: input buffer
2639 * @fmt: formatting of buffer
2640 * @...: resulting arguments
2642 int sscanf(const char *buf, const char *fmt, ...)
2647 va_start(args, fmt);
2648 i = vsscanf(buf, fmt, args);
2653 EXPORT_SYMBOL(sscanf);