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/clk.h>
21 #include <linux/clk-provider.h>
22 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */
23 #include <linux/types.h>
24 #include <linux/string.h>
25 #include <linux/ctype.h>
26 #include <linux/kernel.h>
27 #include <linux/kallsyms.h>
28 #include <linux/math64.h>
29 #include <linux/uaccess.h>
30 #include <linux/ioport.h>
31 #include <linux/dcache.h>
32 #include <linux/cred.h>
33 #include <linux/uuid.h>
34 #include <net/addrconf.h>
36 #include <linux/blkdev.h>
39 #include "../mm/internal.h" /* For the trace_print_flags arrays */
41 #include <asm/page.h> /* for PAGE_SIZE */
42 #include <asm/sections.h> /* for dereference_function_descriptor() */
43 #include <asm/byteorder.h> /* cpu_to_le16 */
45 #include <linux/string_helpers.h>
49 * simple_strtoull - convert a string to an unsigned long long
50 * @cp: The start of the string
51 * @endp: A pointer to the end of the parsed string will be placed here
52 * @base: The number base to use
54 * This function is obsolete. Please use kstrtoull instead.
56 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
58 unsigned long long result;
61 cp = _parse_integer_fixup_radix(cp, &base);
62 rv = _parse_integer(cp, base, &result);
64 cp += (rv & ~KSTRTOX_OVERFLOW);
71 EXPORT_SYMBOL(simple_strtoull);
74 * simple_strtoul - convert a string to an unsigned long
75 * @cp: The start of the string
76 * @endp: A pointer to the end of the parsed string will be placed here
77 * @base: The number base to use
79 * This function is obsolete. Please use kstrtoul instead.
81 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
83 return simple_strtoull(cp, endp, base);
85 EXPORT_SYMBOL(simple_strtoul);
88 * simple_strtol - convert a string to a signed long
89 * @cp: The start of the string
90 * @endp: A pointer to the end of the parsed string will be placed here
91 * @base: The number base to use
93 * This function is obsolete. Please use kstrtol instead.
95 long simple_strtol(const char *cp, char **endp, unsigned int base)
98 return -simple_strtoul(cp + 1, endp, base);
100 return simple_strtoul(cp, endp, base);
102 EXPORT_SYMBOL(simple_strtol);
105 * simple_strtoll - convert a string to a signed long long
106 * @cp: The start of the string
107 * @endp: A pointer to the end of the parsed string will be placed here
108 * @base: The number base to use
110 * This function is obsolete. Please use kstrtoll instead.
112 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
115 return -simple_strtoull(cp + 1, endp, base);
117 return simple_strtoull(cp, endp, base);
119 EXPORT_SYMBOL(simple_strtoll);
121 static noinline_for_stack
122 int skip_atoi(const char **s)
127 i = i*10 + *((*s)++) - '0';
128 } while (isdigit(**s));
134 * Decimal conversion is by far the most typical, and is used for
135 * /proc and /sys data. This directly impacts e.g. top performance
136 * with many processes running. We optimize it for speed by emitting
137 * two characters at a time, using a 200 byte lookup table. This
138 * roughly halves the number of multiplications compared to computing
139 * the digits one at a time. Implementation strongly inspired by the
140 * previous version, which in turn used ideas described at
141 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
142 * from the author, Douglas W. Jones).
144 * It turns out there is precisely one 26 bit fixed-point
145 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
146 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
147 * range happens to be somewhat larger (x <= 1073741898), but that's
148 * irrelevant for our purpose.
150 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
151 * need a 32x32->64 bit multiply, so we simply use the same constant.
153 * For dividing a number in the range [100, 10^4-1] by 100, there are
154 * several options. The simplest is (x * 0x147b) >> 19, which is valid
155 * for all x <= 43698.
158 static const u16 decpair[100] = {
159 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
160 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
161 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
162 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
163 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
164 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
165 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
166 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
167 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
168 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
169 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
174 * This will print a single '0' even if r == 0, since we would
175 * immediately jump to out_r where two 0s would be written but only
176 * one of them accounted for in buf. This is needed by ip4_string
177 * below. All other callers pass a non-zero value of r.
179 static noinline_for_stack
180 char *put_dec_trunc8(char *buf, unsigned r)
188 /* 100 <= r < 10^8 */
189 q = (r * (u64)0x28f5c29) >> 32;
190 *((u16 *)buf) = decpair[r - 100*q];
197 /* 100 <= q < 10^6 */
198 r = (q * (u64)0x28f5c29) >> 32;
199 *((u16 *)buf) = decpair[q - 100*r];
206 /* 100 <= r < 10^4 */
207 q = (r * 0x147b) >> 19;
208 *((u16 *)buf) = decpair[r - 100*q];
215 *((u16 *)buf) = decpair[r];
216 buf += r < 10 ? 1 : 2;
220 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
221 static noinline_for_stack
222 char *put_dec_full8(char *buf, unsigned r)
227 q = (r * (u64)0x28f5c29) >> 32;
228 *((u16 *)buf) = decpair[r - 100*q];
232 r = (q * (u64)0x28f5c29) >> 32;
233 *((u16 *)buf) = decpair[q - 100*r];
237 q = (r * 0x147b) >> 19;
238 *((u16 *)buf) = decpair[r - 100*q];
242 *((u16 *)buf) = decpair[q];
247 static noinline_for_stack
248 char *put_dec(char *buf, unsigned long long n)
250 if (n >= 100*1000*1000)
251 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
252 /* 1 <= n <= 1.6e11 */
253 if (n >= 100*1000*1000)
254 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
256 return put_dec_trunc8(buf, n);
259 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
262 put_dec_full4(char *buf, unsigned r)
267 q = (r * 0x147b) >> 19;
268 *((u16 *)buf) = decpair[r - 100*q];
271 *((u16 *)buf) = decpair[q];
275 * Call put_dec_full4 on x % 10000, return x / 10000.
276 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
277 * holds for all x < 1,128,869,999. The largest value this
278 * helper will ever be asked to convert is 1,125,520,955.
279 * (second call in the put_dec code, assuming n is all-ones).
281 static noinline_for_stack
282 unsigned put_dec_helper4(char *buf, unsigned x)
284 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
286 put_dec_full4(buf, x - q * 10000);
290 /* Based on code by Douglas W. Jones found at
291 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
292 * (with permission from the author).
293 * Performs no 64-bit division and hence should be fast on 32-bit machines.
296 char *put_dec(char *buf, unsigned long long n)
298 uint32_t d3, d2, d1, q, h;
300 if (n < 100*1000*1000)
301 return put_dec_trunc8(buf, n);
303 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
306 d3 = (h >> 16); /* implicit "& 0xffff" */
308 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
309 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
310 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
311 q = put_dec_helper4(buf, q);
313 q += 7671 * d3 + 9496 * d2 + 6 * d1;
314 q = put_dec_helper4(buf+4, q);
316 q += 4749 * d3 + 42 * d2;
317 q = put_dec_helper4(buf+8, q);
322 buf = put_dec_trunc8(buf, q);
323 else while (buf[-1] == '0')
332 * Convert passed number to decimal string.
333 * Returns the length of string. On buffer overflow, returns 0.
335 * If speed is not important, use snprintf(). It's easy to read the code.
337 int num_to_str(char *buf, int size, unsigned long long num)
339 /* put_dec requires 2-byte alignment of the buffer. */
340 char tmp[sizeof(num) * 3] __aligned(2);
343 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
348 len = put_dec(tmp, num) - tmp;
353 for (idx = 0; idx < len; ++idx)
354 buf[idx] = tmp[len - idx - 1];
358 #define SIGN 1 /* unsigned/signed, must be 1 */
359 #define LEFT 2 /* left justified */
360 #define PLUS 4 /* show plus */
361 #define SPACE 8 /* space if plus */
362 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
363 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
364 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
367 FORMAT_TYPE_NONE, /* Just a string part */
369 FORMAT_TYPE_PRECISION,
373 FORMAT_TYPE_PERCENT_CHAR,
375 FORMAT_TYPE_LONG_LONG,
389 unsigned int type:8; /* format_type enum */
390 signed int field_width:24; /* width of output field */
391 unsigned int flags:8; /* flags to number() */
392 unsigned int base:8; /* number base, 8, 10 or 16 only */
393 signed int precision:16; /* # of digits/chars */
395 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
396 #define PRECISION_MAX ((1 << 15) - 1)
398 static noinline_for_stack
399 char *number(char *buf, char *end, unsigned long long num,
400 struct printf_spec spec)
402 /* put_dec requires 2-byte alignment of the buffer. */
403 char tmp[3 * sizeof(num)] __aligned(2);
406 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
408 bool is_zero = num == 0LL;
409 int field_width = spec.field_width;
410 int precision = spec.precision;
412 BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
414 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
415 * produces same digits or (maybe lowercased) letters */
416 locase = (spec.flags & SMALL);
417 if (spec.flags & LEFT)
418 spec.flags &= ~ZEROPAD;
420 if (spec.flags & SIGN) {
421 if ((signed long long)num < 0) {
423 num = -(signed long long)num;
425 } else if (spec.flags & PLUS) {
428 } else if (spec.flags & SPACE) {
440 /* generate full string in tmp[], in reverse order */
443 tmp[i++] = hex_asc_upper[num] | locase;
444 else if (spec.base != 10) { /* 8 or 16 */
445 int mask = spec.base - 1;
451 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
454 } else { /* base 10 */
455 i = put_dec(tmp, num) - tmp;
458 /* printing 100 using %2d gives "100", not "00" */
461 /* leading space padding */
462 field_width -= precision;
463 if (!(spec.flags & (ZEROPAD | LEFT))) {
464 while (--field_width >= 0) {
476 /* "0x" / "0" prefix */
478 if (spec.base == 16 || !is_zero) {
483 if (spec.base == 16) {
485 *buf = ('X' | locase);
489 /* zero or space padding */
490 if (!(spec.flags & LEFT)) {
491 char c = ' ' + (spec.flags & ZEROPAD);
492 BUILD_BUG_ON(' ' + ZEROPAD != '0');
493 while (--field_width >= 0) {
499 /* hmm even more zero padding? */
500 while (i <= --precision) {
505 /* actual digits of result */
511 /* trailing space padding */
512 while (--field_width >= 0) {
521 static noinline_for_stack
522 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
524 struct printf_spec spec;
526 spec.type = FORMAT_TYPE_PTR;
527 spec.field_width = 2 + 2 * size; /* 0x + hex */
528 spec.flags = SPECIAL | SMALL | ZEROPAD;
532 return number(buf, end, num, spec);
535 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
538 if (buf >= end) /* nowhere to put anything */
541 if (size <= spaces) {
542 memset(buf, ' ', size);
546 if (len > size - spaces)
548 memmove(buf + spaces, buf, len);
550 memset(buf, ' ', spaces);
554 * Handle field width padding for a string.
555 * @buf: current buffer position
556 * @n: length of string
557 * @end: end of output buffer
558 * @spec: for field width and flags
559 * Returns: new buffer position after padding.
561 static noinline_for_stack
562 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
566 if (likely(n >= spec.field_width))
568 /* we want to pad the sucker */
569 spaces = spec.field_width - n;
570 if (!(spec.flags & LEFT)) {
571 move_right(buf - n, end, n, spaces);
582 static noinline_for_stack
583 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
586 size_t lim = spec.precision;
588 if ((unsigned long)s < PAGE_SIZE)
600 return widen_string(buf, len, end, spec);
603 static noinline_for_stack
604 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
607 const char *array[4], *s;
608 const struct dentry *p;
613 case '2': case '3': case '4':
614 depth = fmt[1] - '0';
621 for (i = 0; i < depth; i++, d = p) {
622 p = ACCESS_ONCE(d->d_parent);
623 array[i] = ACCESS_ONCE(d->d_name.name);
632 for (n = 0; n != spec.precision; n++, buf++) {
644 return widen_string(buf, n, end, spec);
648 static noinline_for_stack
649 char *bdev_name(char *buf, char *end, struct block_device *bdev,
650 struct printf_spec spec, const char *fmt)
652 struct gendisk *hd = bdev->bd_disk;
654 buf = string(buf, end, hd->disk_name, spec);
655 if (bdev->bd_part->partno) {
656 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
661 buf = number(buf, end, bdev->bd_part->partno, spec);
667 static noinline_for_stack
668 char *symbol_string(char *buf, char *end, void *ptr,
669 struct printf_spec spec, const char *fmt)
672 #ifdef CONFIG_KALLSYMS
673 char sym[KSYM_SYMBOL_LEN];
677 ptr = __builtin_extract_return_addr(ptr);
678 value = (unsigned long)ptr;
680 #ifdef CONFIG_KALLSYMS
682 sprint_backtrace(sym, value);
683 else if (*fmt != 'f' && *fmt != 's')
684 sprint_symbol(sym, value);
686 sprint_symbol_no_offset(sym, value);
688 return string(buf, end, sym, spec);
690 return special_hex_number(buf, end, value, sizeof(void *));
694 static noinline_for_stack
695 char *resource_string(char *buf, char *end, struct resource *res,
696 struct printf_spec spec, const char *fmt)
698 #ifndef IO_RSRC_PRINTK_SIZE
699 #define IO_RSRC_PRINTK_SIZE 6
702 #ifndef MEM_RSRC_PRINTK_SIZE
703 #define MEM_RSRC_PRINTK_SIZE 10
705 static const struct printf_spec io_spec = {
707 .field_width = IO_RSRC_PRINTK_SIZE,
709 .flags = SPECIAL | SMALL | ZEROPAD,
711 static const struct printf_spec mem_spec = {
713 .field_width = MEM_RSRC_PRINTK_SIZE,
715 .flags = SPECIAL | SMALL | ZEROPAD,
717 static const struct printf_spec bus_spec = {
721 .flags = SMALL | ZEROPAD,
723 static const struct printf_spec dec_spec = {
728 static const struct printf_spec str_spec = {
733 static const struct printf_spec flag_spec = {
736 .flags = SPECIAL | SMALL,
739 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
740 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
741 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
742 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
743 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
744 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
745 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
746 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
748 char *p = sym, *pend = sym + sizeof(sym);
749 int decode = (fmt[0] == 'R') ? 1 : 0;
750 const struct printf_spec *specp;
753 if (res->flags & IORESOURCE_IO) {
754 p = string(p, pend, "io ", str_spec);
756 } else if (res->flags & IORESOURCE_MEM) {
757 p = string(p, pend, "mem ", str_spec);
759 } else if (res->flags & IORESOURCE_IRQ) {
760 p = string(p, pend, "irq ", str_spec);
762 } else if (res->flags & IORESOURCE_DMA) {
763 p = string(p, pend, "dma ", str_spec);
765 } else if (res->flags & IORESOURCE_BUS) {
766 p = string(p, pend, "bus ", str_spec);
769 p = string(p, pend, "??? ", str_spec);
773 if (decode && res->flags & IORESOURCE_UNSET) {
774 p = string(p, pend, "size ", str_spec);
775 p = number(p, pend, resource_size(res), *specp);
777 p = number(p, pend, res->start, *specp);
778 if (res->start != res->end) {
780 p = number(p, pend, res->end, *specp);
784 if (res->flags & IORESOURCE_MEM_64)
785 p = string(p, pend, " 64bit", str_spec);
786 if (res->flags & IORESOURCE_PREFETCH)
787 p = string(p, pend, " pref", str_spec);
788 if (res->flags & IORESOURCE_WINDOW)
789 p = string(p, pend, " window", str_spec);
790 if (res->flags & IORESOURCE_DISABLED)
791 p = string(p, pend, " disabled", str_spec);
793 p = string(p, pend, " flags ", str_spec);
794 p = number(p, pend, res->flags, flag_spec);
799 return string(buf, end, sym, spec);
802 static noinline_for_stack
803 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
806 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
807 negative value, fallback to the default */
810 if (spec.field_width == 0)
811 /* nothing to print */
814 if (ZERO_OR_NULL_PTR(addr))
816 return string(buf, end, NULL, spec);
833 if (spec.field_width > 0)
834 len = min_t(int, spec.field_width, 64);
836 for (i = 0; i < len; ++i) {
838 *buf = hex_asc_hi(addr[i]);
841 *buf = hex_asc_lo(addr[i]);
844 if (separator && i != len - 1) {
854 static noinline_for_stack
855 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
856 struct printf_spec spec, const char *fmt)
858 const int CHUNKSZ = 32;
859 int nr_bits = max_t(int, spec.field_width, 0);
863 /* reused to print numbers */
864 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
866 chunksz = nr_bits & (CHUNKSZ - 1);
870 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
871 for (; i >= 0; i -= CHUNKSZ) {
875 chunkmask = ((1ULL << chunksz) - 1);
876 word = i / BITS_PER_LONG;
877 bit = i % BITS_PER_LONG;
878 val = (bitmap[word] >> bit) & chunkmask;
887 spec.field_width = DIV_ROUND_UP(chunksz, 4);
888 buf = number(buf, end, val, spec);
895 static noinline_for_stack
896 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
897 struct printf_spec spec, const char *fmt)
899 int nr_bits = max_t(int, spec.field_width, 0);
900 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
904 /* reused to print numbers */
905 spec = (struct printf_spec){ .base = 10 };
907 rbot = cur = find_first_bit(bitmap, nr_bits);
908 while (cur < nr_bits) {
910 cur = find_next_bit(bitmap, nr_bits, cur + 1);
911 if (cur < nr_bits && cur <= rtop + 1)
921 buf = number(buf, end, rbot, spec);
927 buf = number(buf, end, rtop, spec);
935 static noinline_for_stack
936 char *mac_address_string(char *buf, char *end, u8 *addr,
937 struct printf_spec spec, const char *fmt)
939 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
943 bool reversed = false;
959 for (i = 0; i < 6; i++) {
961 p = hex_byte_pack(p, addr[5 - i]);
963 p = hex_byte_pack(p, addr[i]);
965 if (fmt[0] == 'M' && i != 5)
970 return string(buf, end, mac_addr, spec);
973 static noinline_for_stack
974 char *ip4_string(char *p, const u8 *addr, const char *fmt)
977 bool leading_zeros = (fmt[0] == 'i');
1002 for (i = 0; i < 4; i++) {
1003 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1004 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1005 if (leading_zeros) {
1011 /* reverse the digits in the quad */
1013 *p++ = temp[digits];
1023 static noinline_for_stack
1024 char *ip6_compressed_string(char *p, const char *addr)
1027 unsigned char zerolength[8];
1032 bool needcolon = false;
1034 struct in6_addr in6;
1036 memcpy(&in6, addr, sizeof(struct in6_addr));
1038 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1040 memset(zerolength, 0, sizeof(zerolength));
1047 /* find position of longest 0 run */
1048 for (i = 0; i < range; i++) {
1049 for (j = i; j < range; j++) {
1050 if (in6.s6_addr16[j] != 0)
1055 for (i = 0; i < range; i++) {
1056 if (zerolength[i] > longest) {
1057 longest = zerolength[i];
1061 if (longest == 1) /* don't compress a single 0 */
1065 for (i = 0; i < range; i++) {
1066 if (i == colonpos) {
1067 if (needcolon || i == 0)
1078 /* hex u16 without leading 0s */
1079 word = ntohs(in6.s6_addr16[i]);
1084 p = hex_byte_pack(p, hi);
1086 *p++ = hex_asc_lo(hi);
1087 p = hex_byte_pack(p, lo);
1090 p = hex_byte_pack(p, lo);
1092 *p++ = hex_asc_lo(lo);
1099 p = ip4_string(p, &in6.s6_addr[12], "I4");
1106 static noinline_for_stack
1107 char *ip6_string(char *p, const char *addr, const char *fmt)
1111 for (i = 0; i < 8; i++) {
1112 p = hex_byte_pack(p, *addr++);
1113 p = hex_byte_pack(p, *addr++);
1114 if (fmt[0] == 'I' && i != 7)
1122 static noinline_for_stack
1123 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1124 struct printf_spec spec, const char *fmt)
1126 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1128 if (fmt[0] == 'I' && fmt[2] == 'c')
1129 ip6_compressed_string(ip6_addr, addr);
1131 ip6_string(ip6_addr, addr, fmt);
1133 return string(buf, end, ip6_addr, spec);
1136 static noinline_for_stack
1137 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1138 struct printf_spec spec, const char *fmt)
1140 char ip4_addr[sizeof("255.255.255.255")];
1142 ip4_string(ip4_addr, addr, fmt);
1144 return string(buf, end, ip4_addr, spec);
1147 static noinline_for_stack
1148 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1149 struct printf_spec spec, const char *fmt)
1151 bool have_p = false, have_s = false, have_f = false, have_c = false;
1152 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1153 sizeof(":12345") + sizeof("/123456789") +
1154 sizeof("%1234567890")];
1155 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1156 const u8 *addr = (const u8 *) &sa->sin6_addr;
1157 char fmt6[2] = { fmt[0], '6' };
1161 while (isalpha(*++fmt)) {
1178 if (have_p || have_s || have_f) {
1183 if (fmt6[0] == 'I' && have_c)
1184 p = ip6_compressed_string(ip6_addr + off, addr);
1186 p = ip6_string(ip6_addr + off, addr, fmt6);
1188 if (have_p || have_s || have_f)
1193 p = number(p, pend, ntohs(sa->sin6_port), spec);
1197 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1198 IPV6_FLOWINFO_MASK), spec);
1202 p = number(p, pend, sa->sin6_scope_id, spec);
1206 return string(buf, end, ip6_addr, spec);
1209 static noinline_for_stack
1210 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1211 struct printf_spec spec, const char *fmt)
1213 bool have_p = false;
1214 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1215 char *pend = ip4_addr + sizeof(ip4_addr);
1216 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1217 char fmt4[3] = { fmt[0], '4', 0 };
1220 while (isalpha(*++fmt)) {
1234 p = ip4_string(ip4_addr, addr, fmt4);
1237 p = number(p, pend, ntohs(sa->sin_port), spec);
1241 return string(buf, end, ip4_addr, spec);
1244 static noinline_for_stack
1245 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1250 unsigned int flags = 0;
1253 if (spec.field_width == 0)
1254 return buf; /* nothing to print */
1256 if (ZERO_OR_NULL_PTR(addr))
1257 return string(buf, end, NULL, spec); /* NULL pointer */
1261 switch (fmt[count++]) {
1263 flags |= ESCAPE_ANY;
1266 flags |= ESCAPE_SPECIAL;
1269 flags |= ESCAPE_HEX;
1272 flags |= ESCAPE_NULL;
1275 flags |= ESCAPE_OCTAL;
1281 flags |= ESCAPE_SPACE;
1290 flags = ESCAPE_ANY_NP;
1292 len = spec.field_width < 0 ? 1 : spec.field_width;
1295 * string_escape_mem() writes as many characters as it can to
1296 * the given buffer, and returns the total size of the output
1297 * had the buffer been big enough.
1299 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1304 static noinline_for_stack
1305 char *uuid_string(char *buf, char *end, const u8 *addr,
1306 struct printf_spec spec, const char *fmt)
1308 char uuid[UUID_STRING_LEN + 1];
1311 const u8 *index = uuid_be_index;
1316 uc = true; /* fall-through */
1318 index = uuid_le_index;
1325 for (i = 0; i < 16; i++) {
1327 p = hex_byte_pack_upper(p, addr[index[i]]);
1329 p = hex_byte_pack(p, addr[index[i]]);
1342 return string(buf, end, uuid, spec);
1345 static noinline_for_stack
1346 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1348 unsigned long long num;
1353 num = *(const netdev_features_t *)addr;
1354 size = sizeof(netdev_features_t);
1357 num = (unsigned long)addr;
1358 size = sizeof(unsigned long);
1362 return special_hex_number(buf, end, num, size);
1365 static noinline_for_stack
1366 char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1368 unsigned long long num;
1373 num = *(const dma_addr_t *)addr;
1374 size = sizeof(dma_addr_t);
1378 num = *(const phys_addr_t *)addr;
1379 size = sizeof(phys_addr_t);
1383 return special_hex_number(buf, end, num, size);
1386 static noinline_for_stack
1387 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1390 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1391 return string(buf, end, NULL, spec);
1395 return number(buf, end, clk_get_rate(clk), spec);
1399 #ifdef CONFIG_COMMON_CLK
1400 return string(buf, end, __clk_get_name(clk), spec);
1402 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1408 char *format_flags(char *buf, char *end, unsigned long flags,
1409 const struct trace_print_flags *names)
1412 const struct printf_spec strspec = {
1416 const struct printf_spec numspec = {
1417 .flags = SPECIAL|SMALL,
1423 for ( ; flags && names->name; names++) {
1425 if ((flags & mask) != mask)
1428 buf = string(buf, end, names->name, strspec);
1439 buf = number(buf, end, flags, numspec);
1444 static noinline_for_stack
1445 char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1447 unsigned long flags;
1448 const struct trace_print_flags *names;
1452 flags = *(unsigned long *)flags_ptr;
1453 /* Remove zone id */
1454 flags &= (1UL << NR_PAGEFLAGS) - 1;
1455 names = pageflag_names;
1458 flags = *(unsigned long *)flags_ptr;
1459 names = vmaflag_names;
1462 flags = *(gfp_t *)flags_ptr;
1463 names = gfpflag_names;
1466 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1470 return format_flags(buf, end, flags, names);
1473 int kptr_restrict __read_mostly;
1476 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1477 * by an extra set of alphanumeric characters that are extended format
1480 * Right now we handle:
1482 * - 'F' For symbolic function descriptor pointers with offset
1483 * - 'f' For simple symbolic function names without offset
1484 * - 'S' For symbolic direct pointers with offset
1485 * - 's' For symbolic direct pointers without offset
1486 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1487 * - 'B' For backtraced symbolic direct pointers with offset
1488 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1489 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1490 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1491 * width which must be explicitly specified either as part of the
1492 * format string '%32b[l]' or through '%*b[l]', [l] selects
1493 * range-list format instead of hex format
1494 * - 'M' For a 6-byte MAC address, it prints the address in the
1495 * usual colon-separated hex notation
1496 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1497 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1498 * with a dash-separated hex notation
1499 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1500 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1501 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1502 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1504 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1505 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1506 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1507 * IPv6 omits the colons (01020304...0f)
1508 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1510 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1511 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1512 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1513 * - 'I[6S]c' for IPv6 addresses printed as specified by
1514 * http://tools.ietf.org/html/rfc5952
1515 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1516 * of the following flags (see string_escape_mem() for the
1519 * c - ESCAPE_SPECIAL
1525 * By default ESCAPE_ANY_NP is used.
1526 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1527 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1528 * Options for %pU are:
1529 * b big endian lower case hex (default)
1530 * B big endian UPPER case hex
1531 * l little endian lower case hex
1532 * L little endian UPPER case hex
1533 * big endian output byte order is:
1534 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1535 * little endian output byte order is:
1536 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1537 * - 'V' For a struct va_format which contains a format string * and va_list *,
1538 * call vsnprintf(->format, *->va_list).
1539 * Implements a "recursive vsnprintf".
1540 * Do not use this feature without some mechanism to verify the
1541 * correctness of the format string and va_list arguments.
1542 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1543 * - 'NF' For a netdev_features_t
1544 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1545 * a certain separator (' ' by default):
1549 * The maximum supported length is 64 bytes of the input. Consider
1550 * to use print_hex_dump() for the larger input.
1551 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1552 * (default assumed to be phys_addr_t, passed by reference)
1553 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1554 * - 'D[234]' Same as 'd' but for a struct file
1555 * - 'g' For block_device name (gendisk + partition number)
1556 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1557 * (legacy clock framework) of the clock
1558 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1559 * (legacy clock framework) of the clock
1560 * - 'Cr' For a clock, it prints the current rate of the clock
1561 * - 'G' For flags to be printed as a collection of symbolic strings that would
1562 * construct the specific value. Supported flags given by option:
1563 * p page flags (see struct page) given as pointer to unsigned long
1564 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1565 * v vma flags (VM_*) given as pointer to unsigned long
1567 * ** Please update also Documentation/printk-formats.txt when making changes **
1569 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1570 * function pointers are really function descriptors, which contain a
1571 * pointer to the real address.
1573 static noinline_for_stack
1574 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1575 struct printf_spec spec)
1577 const int default_width = 2 * sizeof(void *);
1579 if (!ptr && *fmt != 'K') {
1581 * Print (null) with the same width as a pointer so it makes
1582 * tabular output look nice.
1584 if (spec.field_width == -1)
1585 spec.field_width = default_width;
1586 return string(buf, end, "(null)", spec);
1592 ptr = dereference_function_descriptor(ptr);
1597 return symbol_string(buf, end, ptr, spec, fmt);
1600 return resource_string(buf, end, ptr, spec, fmt);
1602 return hex_string(buf, end, ptr, spec, fmt);
1606 return bitmap_list_string(buf, end, ptr, spec, fmt);
1608 return bitmap_string(buf, end, ptr, spec, fmt);
1610 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1611 case 'm': /* Contiguous: 000102030405 */
1613 /* [mM]R (Reverse order; Bluetooth) */
1614 return mac_address_string(buf, end, ptr, spec, fmt);
1615 case 'I': /* Formatted IP supported
1617 * 6: 0001:0203:...:0708
1618 * 6c: 1::708 or 1::1.2.3.4
1620 case 'i': /* Contiguous:
1621 * 4: 001.002.003.004
1626 return ip6_addr_string(buf, end, ptr, spec, fmt);
1628 return ip4_addr_string(buf, end, ptr, spec, fmt);
1631 struct sockaddr raw;
1632 struct sockaddr_in v4;
1633 struct sockaddr_in6 v6;
1636 switch (sa->raw.sa_family) {
1638 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1640 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1642 return string(buf, end, "(invalid address)", spec);
1647 return escaped_string(buf, end, ptr, spec, fmt);
1649 return uuid_string(buf, end, ptr, spec, fmt);
1654 va_copy(va, *((struct va_format *)ptr)->va);
1655 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1656 ((struct va_format *)ptr)->fmt, va);
1661 switch (kptr_restrict) {
1663 /* Always print %pK values */
1666 const struct cred *cred;
1669 * kptr_restrict==1 cannot be used in IRQ context
1670 * because its test for CAP_SYSLOG would be meaningless.
1672 if (in_irq() || in_serving_softirq() || in_nmi()) {
1673 if (spec.field_width == -1)
1674 spec.field_width = default_width;
1675 return string(buf, end, "pK-error", spec);
1679 * Only print the real pointer value if the current
1680 * process has CAP_SYSLOG and is running with the
1681 * same credentials it started with. This is because
1682 * access to files is checked at open() time, but %pK
1683 * checks permission at read() time. We don't want to
1684 * leak pointer values if a binary opens a file using
1685 * %pK and then elevates privileges before reading it.
1687 cred = current_cred();
1688 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1689 !uid_eq(cred->euid, cred->uid) ||
1690 !gid_eq(cred->egid, cred->gid))
1696 /* Always print 0's for %pK */
1703 return netdev_bits(buf, end, ptr, fmt);
1705 return address_val(buf, end, ptr, fmt);
1707 return dentry_name(buf, end, ptr, spec, fmt);
1709 return clock(buf, end, ptr, spec, fmt);
1711 return dentry_name(buf, end,
1712 ((const struct file *)ptr)->f_path.dentry,
1716 return bdev_name(buf, end, ptr, spec, fmt);
1720 return flags_string(buf, end, ptr, fmt);
1722 spec.flags |= SMALL;
1723 if (spec.field_width == -1) {
1724 spec.field_width = default_width;
1725 spec.flags |= ZEROPAD;
1729 return number(buf, end, (unsigned long) ptr, spec);
1733 * Helper function to decode printf style format.
1734 * Each call decode a token from the format and return the
1735 * number of characters read (or likely the delta where it wants
1736 * to go on the next call).
1737 * The decoded token is returned through the parameters
1739 * 'h', 'l', or 'L' for integer fields
1740 * 'z' support added 23/7/1999 S.H.
1741 * 'z' changed to 'Z' --davidm 1/25/99
1742 * 't' added for ptrdiff_t
1744 * @fmt: the format string
1745 * @type of the token returned
1746 * @flags: various flags such as +, -, # tokens..
1747 * @field_width: overwritten width
1748 * @base: base of the number (octal, hex, ...)
1749 * @precision: precision of a number
1750 * @qualifier: qualifier of a number (long, size_t, ...)
1752 static noinline_for_stack
1753 int format_decode(const char *fmt, struct printf_spec *spec)
1755 const char *start = fmt;
1758 /* we finished early by reading the field width */
1759 if (spec->type == FORMAT_TYPE_WIDTH) {
1760 if (spec->field_width < 0) {
1761 spec->field_width = -spec->field_width;
1762 spec->flags |= LEFT;
1764 spec->type = FORMAT_TYPE_NONE;
1768 /* we finished early by reading the precision */
1769 if (spec->type == FORMAT_TYPE_PRECISION) {
1770 if (spec->precision < 0)
1771 spec->precision = 0;
1773 spec->type = FORMAT_TYPE_NONE;
1778 spec->type = FORMAT_TYPE_NONE;
1780 for (; *fmt ; ++fmt) {
1785 /* Return the current non-format string */
1786 if (fmt != start || !*fmt)
1792 while (1) { /* this also skips first '%' */
1798 case '-': spec->flags |= LEFT; break;
1799 case '+': spec->flags |= PLUS; break;
1800 case ' ': spec->flags |= SPACE; break;
1801 case '#': spec->flags |= SPECIAL; break;
1802 case '0': spec->flags |= ZEROPAD; break;
1803 default: found = false;
1810 /* get field width */
1811 spec->field_width = -1;
1814 spec->field_width = skip_atoi(&fmt);
1815 else if (*fmt == '*') {
1816 /* it's the next argument */
1817 spec->type = FORMAT_TYPE_WIDTH;
1818 return ++fmt - start;
1822 /* get the precision */
1823 spec->precision = -1;
1826 if (isdigit(*fmt)) {
1827 spec->precision = skip_atoi(&fmt);
1828 if (spec->precision < 0)
1829 spec->precision = 0;
1830 } else if (*fmt == '*') {
1831 /* it's the next argument */
1832 spec->type = FORMAT_TYPE_PRECISION;
1833 return ++fmt - start;
1838 /* get the conversion qualifier */
1840 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1841 _tolower(*fmt) == 'z' || *fmt == 't') {
1843 if (unlikely(qualifier == *fmt)) {
1844 if (qualifier == 'l') {
1847 } else if (qualifier == 'h') {
1858 spec->type = FORMAT_TYPE_CHAR;
1859 return ++fmt - start;
1862 spec->type = FORMAT_TYPE_STR;
1863 return ++fmt - start;
1866 spec->type = FORMAT_TYPE_PTR;
1867 return ++fmt - start;
1870 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1871 return ++fmt - start;
1873 /* integer number formats - set up the flags and "break" */
1879 spec->flags |= SMALL;
1887 spec->flags |= SIGN;
1893 * Since %n poses a greater security risk than
1894 * utility, treat it as any other invalid or
1895 * unsupported format specifier.
1900 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
1901 spec->type = FORMAT_TYPE_INVALID;
1905 if (qualifier == 'L')
1906 spec->type = FORMAT_TYPE_LONG_LONG;
1907 else if (qualifier == 'l') {
1908 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1909 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1910 } else if (_tolower(qualifier) == 'z') {
1911 spec->type = FORMAT_TYPE_SIZE_T;
1912 } else if (qualifier == 't') {
1913 spec->type = FORMAT_TYPE_PTRDIFF;
1914 } else if (qualifier == 'H') {
1915 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1916 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1917 } else if (qualifier == 'h') {
1918 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1919 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1921 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1922 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1925 return ++fmt - start;
1929 set_field_width(struct printf_spec *spec, int width)
1931 spec->field_width = width;
1932 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
1933 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
1938 set_precision(struct printf_spec *spec, int prec)
1940 spec->precision = prec;
1941 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
1942 spec->precision = clamp(prec, 0, PRECISION_MAX);
1947 * vsnprintf - Format a string and place it in a buffer
1948 * @buf: The buffer to place the result into
1949 * @size: The size of the buffer, including the trailing null space
1950 * @fmt: The format string to use
1951 * @args: Arguments for the format string
1953 * This function generally follows C99 vsnprintf, but has some
1954 * extensions and a few limitations:
1957 * %p* is handled by pointer()
1959 * See pointer() or Documentation/printk-formats.txt for more
1960 * extensive description.
1962 * ** Please update the documentation in both places when making changes **
1964 * The return value is the number of characters which would
1965 * be generated for the given input, excluding the trailing
1966 * '\0', as per ISO C99. If you want to have the exact
1967 * number of characters written into @buf as return value
1968 * (not including the trailing '\0'), use vscnprintf(). If the
1969 * return is greater than or equal to @size, the resulting
1970 * string is truncated.
1972 * If you're not already dealing with a va_list consider using snprintf().
1974 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1976 unsigned long long num;
1978 struct printf_spec spec = {0};
1980 /* Reject out-of-range values early. Large positive sizes are
1981 used for unknown buffer sizes. */
1982 if (WARN_ON_ONCE(size > INT_MAX))
1988 /* Make sure end is always >= buf */
1995 const char *old_fmt = fmt;
1996 int read = format_decode(fmt, &spec);
2000 switch (spec.type) {
2001 case FORMAT_TYPE_NONE: {
2004 if (copy > end - str)
2006 memcpy(str, old_fmt, copy);
2012 case FORMAT_TYPE_WIDTH:
2013 set_field_width(&spec, va_arg(args, int));
2016 case FORMAT_TYPE_PRECISION:
2017 set_precision(&spec, va_arg(args, int));
2020 case FORMAT_TYPE_CHAR: {
2023 if (!(spec.flags & LEFT)) {
2024 while (--spec.field_width > 0) {
2031 c = (unsigned char) va_arg(args, int);
2035 while (--spec.field_width > 0) {
2043 case FORMAT_TYPE_STR:
2044 str = string(str, end, va_arg(args, char *), spec);
2047 case FORMAT_TYPE_PTR:
2048 str = pointer(fmt, str, end, va_arg(args, void *),
2050 while (isalnum(*fmt))
2054 case FORMAT_TYPE_PERCENT_CHAR:
2060 case FORMAT_TYPE_INVALID:
2062 * Presumably the arguments passed gcc's type
2063 * checking, but there is no safe or sane way
2064 * for us to continue parsing the format and
2065 * fetching from the va_list; the remaining
2066 * specifiers and arguments would be out of
2072 switch (spec.type) {
2073 case FORMAT_TYPE_LONG_LONG:
2074 num = va_arg(args, long long);
2076 case FORMAT_TYPE_ULONG:
2077 num = va_arg(args, unsigned long);
2079 case FORMAT_TYPE_LONG:
2080 num = va_arg(args, long);
2082 case FORMAT_TYPE_SIZE_T:
2083 if (spec.flags & SIGN)
2084 num = va_arg(args, ssize_t);
2086 num = va_arg(args, size_t);
2088 case FORMAT_TYPE_PTRDIFF:
2089 num = va_arg(args, ptrdiff_t);
2091 case FORMAT_TYPE_UBYTE:
2092 num = (unsigned char) va_arg(args, int);
2094 case FORMAT_TYPE_BYTE:
2095 num = (signed char) va_arg(args, int);
2097 case FORMAT_TYPE_USHORT:
2098 num = (unsigned short) va_arg(args, int);
2100 case FORMAT_TYPE_SHORT:
2101 num = (short) va_arg(args, int);
2103 case FORMAT_TYPE_INT:
2104 num = (int) va_arg(args, int);
2107 num = va_arg(args, unsigned int);
2110 str = number(str, end, num, spec);
2122 /* the trailing null byte doesn't count towards the total */
2126 EXPORT_SYMBOL(vsnprintf);
2129 * vscnprintf - Format a string and place it in a buffer
2130 * @buf: The buffer to place the result into
2131 * @size: The size of the buffer, including the trailing null space
2132 * @fmt: The format string to use
2133 * @args: Arguments for the format string
2135 * The return value is the number of characters which have been written into
2136 * the @buf not including the trailing '\0'. If @size is == 0 the function
2139 * If you're not already dealing with a va_list consider using scnprintf().
2141 * See the vsnprintf() documentation for format string extensions over C99.
2143 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2147 i = vsnprintf(buf, size, fmt, args);
2149 if (likely(i < size))
2155 EXPORT_SYMBOL(vscnprintf);
2158 * snprintf - Format a string and place it in a buffer
2159 * @buf: The buffer to place the result into
2160 * @size: The size of the buffer, including the trailing null space
2161 * @fmt: The format string to use
2162 * @...: Arguments for the format string
2164 * The return value is the number of characters which would be
2165 * generated for the given input, excluding the trailing null,
2166 * as per ISO C99. If the return is greater than or equal to
2167 * @size, the resulting string is truncated.
2169 * See the vsnprintf() documentation for format string extensions over C99.
2171 int snprintf(char *buf, size_t size, const char *fmt, ...)
2176 va_start(args, fmt);
2177 i = vsnprintf(buf, size, fmt, args);
2182 EXPORT_SYMBOL(snprintf);
2185 * scnprintf - Format a string and place it in a buffer
2186 * @buf: The buffer to place the result into
2187 * @size: The size of the buffer, including the trailing null space
2188 * @fmt: The format string to use
2189 * @...: Arguments for the format string
2191 * The return value is the number of characters written into @buf not including
2192 * the trailing '\0'. If @size is == 0 the function returns 0.
2195 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2200 va_start(args, fmt);
2201 i = vscnprintf(buf, size, fmt, args);
2206 EXPORT_SYMBOL(scnprintf);
2209 * vsprintf - Format a string and place it in a buffer
2210 * @buf: The buffer to place the result into
2211 * @fmt: The format string to use
2212 * @args: Arguments for the format string
2214 * The function returns the number of characters written
2215 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2218 * If you're not already dealing with a va_list consider using sprintf().
2220 * See the vsnprintf() documentation for format string extensions over C99.
2222 int vsprintf(char *buf, const char *fmt, va_list args)
2224 return vsnprintf(buf, INT_MAX, fmt, args);
2226 EXPORT_SYMBOL(vsprintf);
2229 * sprintf - Format a string and place it in a buffer
2230 * @buf: The buffer to place the result into
2231 * @fmt: The format string to use
2232 * @...: Arguments for the format string
2234 * The function returns the number of characters written
2235 * into @buf. Use snprintf() or scnprintf() in order to avoid
2238 * See the vsnprintf() documentation for format string extensions over C99.
2240 int sprintf(char *buf, const char *fmt, ...)
2245 va_start(args, fmt);
2246 i = vsnprintf(buf, INT_MAX, fmt, args);
2251 EXPORT_SYMBOL(sprintf);
2253 #ifdef CONFIG_BINARY_PRINTF
2256 * vbin_printf() - VA arguments to binary data
2257 * bstr_printf() - Binary data to text string
2261 * vbin_printf - Parse a format string and place args' binary value in a buffer
2262 * @bin_buf: The buffer to place args' binary value
2263 * @size: The size of the buffer(by words(32bits), not characters)
2264 * @fmt: The format string to use
2265 * @args: Arguments for the format string
2267 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2270 * The return value is the number of words(32bits) which would be generated for
2274 * If the return value is greater than @size, the resulting bin_buf is NOT
2275 * valid for bstr_printf().
2277 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2279 struct printf_spec spec = {0};
2282 str = (char *)bin_buf;
2283 end = (char *)(bin_buf + size);
2285 #define save_arg(type) \
2287 if (sizeof(type) == 8) { \
2288 unsigned long long value; \
2289 str = PTR_ALIGN(str, sizeof(u32)); \
2290 value = va_arg(args, unsigned long long); \
2291 if (str + sizeof(type) <= end) { \
2292 *(u32 *)str = *(u32 *)&value; \
2293 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2296 unsigned long value; \
2297 str = PTR_ALIGN(str, sizeof(type)); \
2298 value = va_arg(args, int); \
2299 if (str + sizeof(type) <= end) \
2300 *(typeof(type) *)str = (type)value; \
2302 str += sizeof(type); \
2306 int read = format_decode(fmt, &spec);
2310 switch (spec.type) {
2311 case FORMAT_TYPE_NONE:
2312 case FORMAT_TYPE_PERCENT_CHAR:
2314 case FORMAT_TYPE_INVALID:
2317 case FORMAT_TYPE_WIDTH:
2318 case FORMAT_TYPE_PRECISION:
2322 case FORMAT_TYPE_CHAR:
2326 case FORMAT_TYPE_STR: {
2327 const char *save_str = va_arg(args, char *);
2330 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2331 || (unsigned long)save_str < PAGE_SIZE)
2332 save_str = "(null)";
2333 len = strlen(save_str) + 1;
2334 if (str + len < end)
2335 memcpy(str, save_str, len);
2340 case FORMAT_TYPE_PTR:
2342 /* skip all alphanumeric pointer suffixes */
2343 while (isalnum(*fmt))
2348 switch (spec.type) {
2350 case FORMAT_TYPE_LONG_LONG:
2351 save_arg(long long);
2353 case FORMAT_TYPE_ULONG:
2354 case FORMAT_TYPE_LONG:
2355 save_arg(unsigned long);
2357 case FORMAT_TYPE_SIZE_T:
2360 case FORMAT_TYPE_PTRDIFF:
2361 save_arg(ptrdiff_t);
2363 case FORMAT_TYPE_UBYTE:
2364 case FORMAT_TYPE_BYTE:
2367 case FORMAT_TYPE_USHORT:
2368 case FORMAT_TYPE_SHORT:
2378 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2381 EXPORT_SYMBOL_GPL(vbin_printf);
2384 * bstr_printf - Format a string from binary arguments and place it in a buffer
2385 * @buf: The buffer to place the result into
2386 * @size: The size of the buffer, including the trailing null space
2387 * @fmt: The format string to use
2388 * @bin_buf: Binary arguments for the format string
2390 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2391 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2392 * a binary buffer that generated by vbin_printf.
2394 * The format follows C99 vsnprintf, but has some extensions:
2395 * see vsnprintf comment for details.
2397 * The return value is the number of characters which would
2398 * be generated for the given input, excluding the trailing
2399 * '\0', as per ISO C99. If you want to have the exact
2400 * number of characters written into @buf as return value
2401 * (not including the trailing '\0'), use vscnprintf(). If the
2402 * return is greater than or equal to @size, the resulting
2403 * string is truncated.
2405 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2407 struct printf_spec spec = {0};
2409 const char *args = (const char *)bin_buf;
2411 if (WARN_ON_ONCE(size > INT_MAX))
2417 #define get_arg(type) \
2419 typeof(type) value; \
2420 if (sizeof(type) == 8) { \
2421 args = PTR_ALIGN(args, sizeof(u32)); \
2422 *(u32 *)&value = *(u32 *)args; \
2423 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2425 args = PTR_ALIGN(args, sizeof(type)); \
2426 value = *(typeof(type) *)args; \
2428 args += sizeof(type); \
2432 /* Make sure end is always >= buf */
2439 const char *old_fmt = fmt;
2440 int read = format_decode(fmt, &spec);
2444 switch (spec.type) {
2445 case FORMAT_TYPE_NONE: {
2448 if (copy > end - str)
2450 memcpy(str, old_fmt, copy);
2456 case FORMAT_TYPE_WIDTH:
2457 set_field_width(&spec, get_arg(int));
2460 case FORMAT_TYPE_PRECISION:
2461 set_precision(&spec, get_arg(int));
2464 case FORMAT_TYPE_CHAR: {
2467 if (!(spec.flags & LEFT)) {
2468 while (--spec.field_width > 0) {
2474 c = (unsigned char) get_arg(char);
2478 while (--spec.field_width > 0) {
2486 case FORMAT_TYPE_STR: {
2487 const char *str_arg = args;
2488 args += strlen(str_arg) + 1;
2489 str = string(str, end, (char *)str_arg, spec);
2493 case FORMAT_TYPE_PTR:
2494 str = pointer(fmt, str, end, get_arg(void *), spec);
2495 while (isalnum(*fmt))
2499 case FORMAT_TYPE_PERCENT_CHAR:
2505 case FORMAT_TYPE_INVALID:
2509 unsigned long long num;
2511 switch (spec.type) {
2513 case FORMAT_TYPE_LONG_LONG:
2514 num = get_arg(long long);
2516 case FORMAT_TYPE_ULONG:
2517 case FORMAT_TYPE_LONG:
2518 num = get_arg(unsigned long);
2520 case FORMAT_TYPE_SIZE_T:
2521 num = get_arg(size_t);
2523 case FORMAT_TYPE_PTRDIFF:
2524 num = get_arg(ptrdiff_t);
2526 case FORMAT_TYPE_UBYTE:
2527 num = get_arg(unsigned char);
2529 case FORMAT_TYPE_BYTE:
2530 num = get_arg(signed char);
2532 case FORMAT_TYPE_USHORT:
2533 num = get_arg(unsigned short);
2535 case FORMAT_TYPE_SHORT:
2536 num = get_arg(short);
2538 case FORMAT_TYPE_UINT:
2539 num = get_arg(unsigned int);
2545 str = number(str, end, num, spec);
2547 } /* switch(spec.type) */
2560 /* the trailing null byte doesn't count towards the total */
2563 EXPORT_SYMBOL_GPL(bstr_printf);
2566 * bprintf - Parse a format string and place args' binary value in a buffer
2567 * @bin_buf: The buffer to place args' binary value
2568 * @size: The size of the buffer(by words(32bits), not characters)
2569 * @fmt: The format string to use
2570 * @...: Arguments for the format string
2572 * The function returns the number of words(u32) written
2575 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2580 va_start(args, fmt);
2581 ret = vbin_printf(bin_buf, size, fmt, args);
2586 EXPORT_SYMBOL_GPL(bprintf);
2588 #endif /* CONFIG_BINARY_PRINTF */
2591 * vsscanf - Unformat a buffer into a list of arguments
2592 * @buf: input buffer
2593 * @fmt: format of buffer
2596 int vsscanf(const char *buf, const char *fmt, va_list args)
2598 const char *str = buf;
2606 unsigned long long u;
2612 /* skip any white space in format */
2613 /* white space in format matchs any amount of
2614 * white space, including none, in the input.
2616 if (isspace(*fmt)) {
2617 fmt = skip_spaces(++fmt);
2618 str = skip_spaces(str);
2621 /* anything that is not a conversion must match exactly */
2622 if (*fmt != '%' && *fmt) {
2623 if (*fmt++ != *str++)
2632 /* skip this conversion.
2633 * advance both strings to next white space
2638 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2639 /* '%*[' not yet supported, invalid format */
2644 while (!isspace(*str) && *str)
2649 /* get field width */
2651 if (isdigit(*fmt)) {
2652 field_width = skip_atoi(&fmt);
2653 if (field_width <= 0)
2657 /* get conversion qualifier */
2659 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2660 _tolower(*fmt) == 'z') {
2662 if (unlikely(qualifier == *fmt)) {
2663 if (qualifier == 'h') {
2666 } else if (qualifier == 'l') {
2677 /* return number of characters read so far */
2678 *va_arg(args, int *) = str - buf;
2692 char *s = (char *)va_arg(args, char*);
2693 if (field_width == -1)
2697 } while (--field_width > 0 && *str);
2703 char *s = (char *)va_arg(args, char *);
2704 if (field_width == -1)
2705 field_width = SHRT_MAX;
2706 /* first, skip leading white space in buffer */
2707 str = skip_spaces(str);
2709 /* now copy until next white space */
2710 while (*str && !isspace(*str) && field_width--)
2717 * Warning: This implementation of the '[' conversion specifier
2718 * deviates from its glibc counterpart in the following ways:
2719 * (1) It does NOT support ranges i.e. '-' is NOT a special
2721 * (2) It cannot match the closing bracket ']' itself
2722 * (3) A field width is required
2723 * (4) '%*[' (discard matching input) is currently not supported
2726 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2727 * buf1, buf2, buf3);
2733 char *s = (char *)va_arg(args, char *);
2734 DECLARE_BITMAP(set, 256) = {0};
2735 unsigned int len = 0;
2736 bool negate = (*fmt == '^');
2738 /* field width is required */
2739 if (field_width == -1)
2745 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2746 set_bit((u8)*fmt, set);
2748 /* no ']' or no character set found */
2754 bitmap_complement(set, set, 256);
2755 /* exclude null '\0' byte */
2759 /* match must be non-empty */
2760 if (!test_bit((u8)*str, set))
2763 while (test_bit((u8)*str, set) && field_width--)
2783 /* looking for '%' in str */
2788 /* invalid format; stop here */
2792 /* have some sort of integer conversion.
2793 * first, skip white space in buffer.
2795 str = skip_spaces(str);
2798 if (is_sign && digit == '-')
2802 || (base == 16 && !isxdigit(digit))
2803 || (base == 10 && !isdigit(digit))
2804 || (base == 8 && (!isdigit(digit) || digit > '7'))
2805 || (base == 0 && !isdigit(digit)))
2809 val.s = qualifier != 'L' ?
2810 simple_strtol(str, &next, base) :
2811 simple_strtoll(str, &next, base);
2813 val.u = qualifier != 'L' ?
2814 simple_strtoul(str, &next, base) :
2815 simple_strtoull(str, &next, base);
2817 if (field_width > 0 && next - str > field_width) {
2819 _parse_integer_fixup_radix(str, &base);
2820 while (next - str > field_width) {
2822 val.s = div_s64(val.s, base);
2824 val.u = div_u64(val.u, base);
2829 switch (qualifier) {
2830 case 'H': /* that's 'hh' in format */
2832 *va_arg(args, signed char *) = val.s;
2834 *va_arg(args, unsigned char *) = val.u;
2838 *va_arg(args, short *) = val.s;
2840 *va_arg(args, unsigned short *) = val.u;
2844 *va_arg(args, long *) = val.s;
2846 *va_arg(args, unsigned long *) = val.u;
2850 *va_arg(args, long long *) = val.s;
2852 *va_arg(args, unsigned long long *) = val.u;
2856 *va_arg(args, size_t *) = val.u;
2860 *va_arg(args, int *) = val.s;
2862 *va_arg(args, unsigned int *) = val.u;
2874 EXPORT_SYMBOL(vsscanf);
2877 * sscanf - Unformat a buffer into a list of arguments
2878 * @buf: input buffer
2879 * @fmt: formatting of buffer
2880 * @...: resulting arguments
2882 int sscanf(const char *buf, const char *fmt, ...)
2887 va_start(args, fmt);
2888 i = vsscanf(buf, fmt, args);
2893 EXPORT_SYMBOL(sscanf);