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Merge branch 'for-linus' of git://github.com/dtor/input
[linux-btrfs-devel.git] / lib / vsprintf.c
blobd7222a9c82671ea835377022fc3fbaf9f2364cd0
1 /*
2 * linux/lib/vsprintf.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8 /*
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
10 */
11
12 /*
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
17 */
18
19 #include <stdarg.h>
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/uaccess.h>
27 #include <linux/ioport.h>
28 #include <net/addrconf.h>
29
30 #include <asm/page.h> /* for PAGE_SIZE */
31 #include <asm/div64.h>
32 #include <asm/sections.h> /* for dereference_function_descriptor() */
33
34 static unsigned int simple_guess_base(const char *cp)
35 {
36 if (cp[0] == '0') {
37 if (_tolower(cp[1]) == 'x' && isxdigit(cp[2]))
38 return 16;
39 else
40 return 8;
41 } else {
42 return 10;
43 }
44 }
45
46 /**
47 * simple_strtoull - convert a string to an unsigned long long
48 * @cp: The start of the string
49 * @endp: A pointer to the end of the parsed string will be placed here
50 * @base: The number base to use
51 */
52 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
53 {
54 unsigned long long result = 0;
55
56 if (!base)
57 base = simple_guess_base(cp);
58
59 if (base == 16 && cp[0] == '0' && _tolower(cp[1]) == 'x')
60 cp += 2;
61
62 while (isxdigit(*cp)) {
63 unsigned int value;
64
65 value = isdigit(*cp) ? *cp - '0' : _tolower(*cp) - 'a' + 10;
66 if (value >= base)
67 break;
68 result = result * base + value;
69 cp++;
70 }
71 if (endp)
72 *endp = (char *)cp;
73
74 return result;
75 }
76 EXPORT_SYMBOL(simple_strtoull);
77
78 /**
79 * simple_strtoul - convert a string to an unsigned 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
83 */
84 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
85 {
86 return simple_strtoull(cp, endp, base);
87 }
88 EXPORT_SYMBOL(simple_strtoul);
89
90 /**
91 * simple_strtol - convert a string to a signed long
92 * @cp: The start of the string
93 * @endp: A pointer to the end of the parsed string will be placed here
94 * @base: The number base to use
95 */
96 long simple_strtol(const char *cp, char **endp, unsigned int base)
97 {
98 if (*cp == '-')
99 return -simple_strtoul(cp + 1, endp, base);
100
101 return simple_strtoul(cp, endp, base);
102 }
103 EXPORT_SYMBOL(simple_strtol);
104
105 /**
106 * simple_strtoll - convert a string to a signed long long
107 * @cp: The start of the string
108 * @endp: A pointer to the end of the parsed string will be placed here
109 * @base: The number base to use
110 */
111 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
112 {
113 if (*cp == '-')
114 return -simple_strtoull(cp + 1, endp, base);
115
116 return simple_strtoull(cp, endp, base);
117 }
118 EXPORT_SYMBOL(simple_strtoll);
119
120 static noinline_for_stack
121 int skip_atoi(const char **s)
122 {
123 int i = 0;
124
125 while (isdigit(**s))
126 i = i*10 + *((*s)++) - '0';
127
128 return i;
129 }
130
131 /* Decimal conversion is by far the most typical, and is used
132 * for /proc and /sys data. This directly impacts e.g. top performance
133 * with many processes running. We optimize it for speed
134 * using code from
135 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
136 * (with permission from the author, Douglas W. Jones). */
137
138 /* Formats correctly any integer in [0,99999].
139 * Outputs from one to five digits depending on input.
140 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
141 static noinline_for_stack
142 char *put_dec_trunc(char *buf, unsigned q)
143 {
144 unsigned d3, d2, d1, d0;
145 d1 = (q>>4) & 0xf;
146 d2 = (q>>8) & 0xf;
147 d3 = (q>>12);
148
149 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
150 q = (d0 * 0xcd) >> 11;
151 d0 = d0 - 10*q;
152 *buf++ = d0 + '0'; /* least significant digit */
153 d1 = q + 9*d3 + 5*d2 + d1;
154 if (d1 != 0) {
155 q = (d1 * 0xcd) >> 11;
156 d1 = d1 - 10*q;
157 *buf++ = d1 + '0'; /* next digit */
158
159 d2 = q + 2*d2;
160 if ((d2 != 0) || (d3 != 0)) {
161 q = (d2 * 0xd) >> 7;
162 d2 = d2 - 10*q;
163 *buf++ = d2 + '0'; /* next digit */
164
165 d3 = q + 4*d3;
166 if (d3 != 0) {
167 q = (d3 * 0xcd) >> 11;
168 d3 = d3 - 10*q;
169 *buf++ = d3 + '0'; /* next digit */
170 if (q != 0)
171 *buf++ = q + '0'; /* most sign. digit */
172 }
173 }
174 }
175
176 return buf;
177 }
178 /* Same with if's removed. Always emits five digits */
179 static noinline_for_stack
180 char *put_dec_full(char *buf, unsigned q)
181 {
182 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
183 /* but anyway, gcc produces better code with full-sized ints */
184 unsigned d3, d2, d1, d0;
185 d1 = (q>>4) & 0xf;
186 d2 = (q>>8) & 0xf;
187 d3 = (q>>12);
188
189 /*
190 * Possible ways to approx. divide by 10
191 * gcc -O2 replaces multiply with shifts and adds
192 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
193 * (x * 0x67) >> 10: 1100111
194 * (x * 0x34) >> 9: 110100 - same
195 * (x * 0x1a) >> 8: 11010 - same
196 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
197 */
198 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
199 q = (d0 * 0xcd) >> 11;
200 d0 = d0 - 10*q;
201 *buf++ = d0 + '0';
202 d1 = q + 9*d3 + 5*d2 + d1;
203 q = (d1 * 0xcd) >> 11;
204 d1 = d1 - 10*q;
205 *buf++ = d1 + '0';
206
207 d2 = q + 2*d2;
208 q = (d2 * 0xd) >> 7;
209 d2 = d2 - 10*q;
210 *buf++ = d2 + '0';
211
212 d3 = q + 4*d3;
213 q = (d3 * 0xcd) >> 11; /* - shorter code */
214 /* q = (d3 * 0x67) >> 10; - would also work */
215 d3 = d3 - 10*q;
216 *buf++ = d3 + '0';
217 *buf++ = q + '0';
218
219 return buf;
220 }
221 /* No inlining helps gcc to use registers better */
222 static noinline_for_stack
223 char *put_dec(char *buf, unsigned long long num)
224 {
225 while (1) {
226 unsigned rem;
227 if (num < 100000)
228 return put_dec_trunc(buf, num);
229 rem = do_div(num, 100000);
230 buf = put_dec_full(buf, rem);
231 }
232 }
233
234 #define ZEROPAD 1 /* pad with zero */
235 #define SIGN 2 /* unsigned/signed long */
236 #define PLUS 4 /* show plus */
237 #define SPACE 8 /* space if plus */
238 #define LEFT 16 /* left justified */
239 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
240 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
241
242 enum format_type {
243 FORMAT_TYPE_NONE, /* Just a string part */
244 FORMAT_TYPE_WIDTH,
245 FORMAT_TYPE_PRECISION,
246 FORMAT_TYPE_CHAR,
247 FORMAT_TYPE_STR,
248 FORMAT_TYPE_PTR,
249 FORMAT_TYPE_PERCENT_CHAR,
250 FORMAT_TYPE_INVALID,
251 FORMAT_TYPE_LONG_LONG,
252 FORMAT_TYPE_ULONG,
253 FORMAT_TYPE_LONG,
254 FORMAT_TYPE_UBYTE,
255 FORMAT_TYPE_BYTE,
256 FORMAT_TYPE_USHORT,
257 FORMAT_TYPE_SHORT,
258 FORMAT_TYPE_UINT,
259 FORMAT_TYPE_INT,
260 FORMAT_TYPE_NRCHARS,
261 FORMAT_TYPE_SIZE_T,
262 FORMAT_TYPE_PTRDIFF
263 };
264
265 struct printf_spec {
266 u8 type; /* format_type enum */
267 u8 flags; /* flags to number() */
268 u8 base; /* number base, 8, 10 or 16 only */
269 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
270 s16 field_width; /* width of output field */
271 s16 precision; /* # of digits/chars */
272 };
273
274 static noinline_for_stack
275 char *number(char *buf, char *end, unsigned long long num,
276 struct printf_spec spec)
277 {
278 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
279 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
280
281 char tmp[66];
282 char sign;
283 char locase;
284 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
285 int i;
286
287 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
288 * produces same digits or (maybe lowercased) letters */
289 locase = (spec.flags & SMALL);
290 if (spec.flags & LEFT)
291 spec.flags &= ~ZEROPAD;
292 sign = 0;
293 if (spec.flags & SIGN) {
294 if ((signed long long)num < 0) {
295 sign = '-';
296 num = -(signed long long)num;
297 spec.field_width--;
298 } else if (spec.flags & PLUS) {
299 sign = '+';
300 spec.field_width--;
301 } else if (spec.flags & SPACE) {
302 sign = ' ';
303 spec.field_width--;
304 }
305 }
306 if (need_pfx) {
307 spec.field_width--;
308 if (spec.base == 16)
309 spec.field_width--;
310 }
311
312 /* generate full string in tmp[], in reverse order */
313 i = 0;
314 if (num == 0)
315 tmp[i++] = '0';
316 /* Generic code, for any base:
317 else do {
318 tmp[i++] = (digits[do_div(num,base)] | locase);
319 } while (num != 0);
320 */
321 else if (spec.base != 10) { /* 8 or 16 */
322 int mask = spec.base - 1;
323 int shift = 3;
324
325 if (spec.base == 16)
326 shift = 4;
327 do {
328 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
329 num >>= shift;
330 } while (num);
331 } else { /* base 10 */
332 i = put_dec(tmp, num) - tmp;
333 }
334
335 /* printing 100 using %2d gives "100", not "00" */
336 if (i > spec.precision)
337 spec.precision = i;
338 /* leading space padding */
339 spec.field_width -= spec.precision;
340 if (!(spec.flags & (ZEROPAD+LEFT))) {
341 while (--spec.field_width >= 0) {
342 if (buf < end)
343 *buf = ' ';
344 ++buf;
345 }
346 }
347 /* sign */
348 if (sign) {
349 if (buf < end)
350 *buf = sign;
351 ++buf;
352 }
353 /* "0x" / "0" prefix */
354 if (need_pfx) {
355 if (buf < end)
356 *buf = '0';
357 ++buf;
358 if (spec.base == 16) {
359 if (buf < end)
360 *buf = ('X' | locase);
361 ++buf;
362 }
363 }
364 /* zero or space padding */
365 if (!(spec.flags & LEFT)) {
366 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
367 while (--spec.field_width >= 0) {
368 if (buf < end)
369 *buf = c;
370 ++buf;
371 }
372 }
373 /* hmm even more zero padding? */
374 while (i <= --spec.precision) {
375 if (buf < end)
376 *buf = '0';
377 ++buf;
378 }
379 /* actual digits of result */
380 while (--i >= 0) {
381 if (buf < end)
382 *buf = tmp[i];
383 ++buf;
384 }
385 /* trailing space padding */
386 while (--spec.field_width >= 0) {
387 if (buf < end)
388 *buf = ' ';
389 ++buf;
390 }
391
392 return buf;
393 }
394
395 static noinline_for_stack
396 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
397 {
398 int len, i;
399
400 if ((unsigned long)s < PAGE_SIZE)
401 s = "(null)";
402
403 len = strnlen(s, spec.precision);
404
405 if (!(spec.flags & LEFT)) {
406 while (len < spec.field_width--) {
407 if (buf < end)
408 *buf = ' ';
409 ++buf;
410 }
411 }
412 for (i = 0; i < len; ++i) {
413 if (buf < end)
414 *buf = *s;
415 ++buf; ++s;
416 }
417 while (len < spec.field_width--) {
418 if (buf < end)
419 *buf = ' ';
420 ++buf;
421 }
422
423 return buf;
424 }
425
426 static noinline_for_stack
427 char *symbol_string(char *buf, char *end, void *ptr,
428 struct printf_spec spec, char ext)
429 {
430 unsigned long value = (unsigned long) ptr;
431 #ifdef CONFIG_KALLSYMS
432 char sym[KSYM_SYMBOL_LEN];
433 if (ext == 'B')
434 sprint_backtrace(sym, value);
435 else if (ext != 'f' && ext != 's')
436 sprint_symbol(sym, value);
437 else
438 kallsyms_lookup(value, NULL, NULL, NULL, sym);
439
440 return string(buf, end, sym, spec);
441 #else
442 spec.field_width = 2 * sizeof(void *);
443 spec.flags |= SPECIAL | SMALL | ZEROPAD;
444 spec.base = 16;
445
446 return number(buf, end, value, spec);
447 #endif
448 }
449
450 static noinline_for_stack
451 char *resource_string(char *buf, char *end, struct resource *res,
452 struct printf_spec spec, const char *fmt)
453 {
454 #ifndef IO_RSRC_PRINTK_SIZE
455 #define IO_RSRC_PRINTK_SIZE 6
456 #endif
457
458 #ifndef MEM_RSRC_PRINTK_SIZE
459 #define MEM_RSRC_PRINTK_SIZE 10
460 #endif
461 static const struct printf_spec io_spec = {
462 .base = 16,
463 .field_width = IO_RSRC_PRINTK_SIZE,
464 .precision = -1,
465 .flags = SPECIAL | SMALL | ZEROPAD,
466 };
467 static const struct printf_spec mem_spec = {
468 .base = 16,
469 .field_width = MEM_RSRC_PRINTK_SIZE,
470 .precision = -1,
471 .flags = SPECIAL | SMALL | ZEROPAD,
472 };
473 static const struct printf_spec bus_spec = {
474 .base = 16,
475 .field_width = 2,
476 .precision = -1,
477 .flags = SMALL | ZEROPAD,
478 };
479 static const struct printf_spec dec_spec = {
480 .base = 10,
481 .precision = -1,
482 .flags = 0,
483 };
484 static const struct printf_spec str_spec = {
485 .field_width = -1,
486 .precision = 10,
487 .flags = LEFT,
488 };
489 static const struct printf_spec flag_spec = {
490 .base = 16,
491 .precision = -1,
492 .flags = SPECIAL | SMALL,
493 };
494
495 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
496 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
497 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
498 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
499 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
500 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
501 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
502 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
503
504 char *p = sym, *pend = sym + sizeof(sym);
505 int decode = (fmt[0] == 'R') ? 1 : 0;
506 const struct printf_spec *specp;
507
508 *p++ = '[';
509 if (res->flags & IORESOURCE_IO) {
510 p = string(p, pend, "io ", str_spec);
511 specp = &io_spec;
512 } else if (res->flags & IORESOURCE_MEM) {
513 p = string(p, pend, "mem ", str_spec);
514 specp = &mem_spec;
515 } else if (res->flags & IORESOURCE_IRQ) {
516 p = string(p, pend, "irq ", str_spec);
517 specp = &dec_spec;
518 } else if (res->flags & IORESOURCE_DMA) {
519 p = string(p, pend, "dma ", str_spec);
520 specp = &dec_spec;
521 } else if (res->flags & IORESOURCE_BUS) {
522 p = string(p, pend, "bus ", str_spec);
523 specp = &bus_spec;
524 } else {
525 p = string(p, pend, "??? ", str_spec);
526 specp = &mem_spec;
527 decode = 0;
528 }
529 p = number(p, pend, res->start, *specp);
530 if (res->start != res->end) {
531 *p++ = '-';
532 p = number(p, pend, res->end, *specp);
533 }
534 if (decode) {
535 if (res->flags & IORESOURCE_MEM_64)
536 p = string(p, pend, " 64bit", str_spec);
537 if (res->flags & IORESOURCE_PREFETCH)
538 p = string(p, pend, " pref", str_spec);
539 if (res->flags & IORESOURCE_WINDOW)
540 p = string(p, pend, " window", str_spec);
541 if (res->flags & IORESOURCE_DISABLED)
542 p = string(p, pend, " disabled", str_spec);
543 } else {
544 p = string(p, pend, " flags ", str_spec);
545 p = number(p, pend, res->flags, flag_spec);
546 }
547 *p++ = ']';
548 *p = '\0';
549
550 return string(buf, end, sym, spec);
551 }
552
553 static noinline_for_stack
554 char *mac_address_string(char *buf, char *end, u8 *addr,
555 struct printf_spec spec, const char *fmt)
556 {
557 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
558 char *p = mac_addr;
559 int i;
560 char separator;
561
562 if (fmt[1] == 'F') { /* FDDI canonical format */
563 separator = '-';
564 } else {
565 separator = ':';
566 }
567
568 for (i = 0; i < 6; i++) {
569 p = pack_hex_byte(p, addr[i]);
570 if (fmt[0] == 'M' && i != 5)
571 *p++ = separator;
572 }
573 *p = '\0';
574
575 return string(buf, end, mac_addr, spec);
576 }
577
578 static noinline_for_stack
579 char *ip4_string(char *p, const u8 *addr, const char *fmt)
580 {
581 int i;
582 bool leading_zeros = (fmt[0] == 'i');
583 int index;
584 int step;
585
586 switch (fmt[2]) {
587 case 'h':
588 #ifdef __BIG_ENDIAN
589 index = 0;
590 step = 1;
591 #else
592 index = 3;
593 step = -1;
594 #endif
595 break;
596 case 'l':
597 index = 3;
598 step = -1;
599 break;
600 case 'n':
601 case 'b':
602 default:
603 index = 0;
604 step = 1;
605 break;
606 }
607 for (i = 0; i < 4; i++) {
608 char temp[3]; /* hold each IP quad in reverse order */
609 int digits = put_dec_trunc(temp, addr[index]) - temp;
610 if (leading_zeros) {
611 if (digits < 3)
612 *p++ = '0';
613 if (digits < 2)
614 *p++ = '0';
615 }
616 /* reverse the digits in the quad */
617 while (digits--)
618 *p++ = temp[digits];
619 if (i < 3)
620 *p++ = '.';
621 index += step;
622 }
623 *p = '\0';
624
625 return p;
626 }
627
628 static noinline_for_stack
629 char *ip6_compressed_string(char *p, const char *addr)
630 {
631 int i, j, range;
632 unsigned char zerolength[8];
633 int longest = 1;
634 int colonpos = -1;
635 u16 word;
636 u8 hi, lo;
637 bool needcolon = false;
638 bool useIPv4;
639 struct in6_addr in6;
640
641 memcpy(&in6, addr, sizeof(struct in6_addr));
642
643 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
644
645 memset(zerolength, 0, sizeof(zerolength));
646
647 if (useIPv4)
648 range = 6;
649 else
650 range = 8;
651
652 /* find position of longest 0 run */
653 for (i = 0; i < range; i++) {
654 for (j = i; j < range; j++) {
655 if (in6.s6_addr16[j] != 0)
656 break;
657 zerolength[i]++;
658 }
659 }
660 for (i = 0; i < range; i++) {
661 if (zerolength[i] > longest) {
662 longest = zerolength[i];
663 colonpos = i;
664 }
665 }
666 if (longest == 1) /* don't compress a single 0 */
667 colonpos = -1;
668
669 /* emit address */
670 for (i = 0; i < range; i++) {
671 if (i == colonpos) {
672 if (needcolon || i == 0)
673 *p++ = ':';
674 *p++ = ':';
675 needcolon = false;
676 i += longest - 1;
677 continue;
678 }
679 if (needcolon) {
680 *p++ = ':';
681 needcolon = false;
682 }
683 /* hex u16 without leading 0s */
684 word = ntohs(in6.s6_addr16[i]);
685 hi = word >> 8;
686 lo = word & 0xff;
687 if (hi) {
688 if (hi > 0x0f)
689 p = pack_hex_byte(p, hi);
690 else
691 *p++ = hex_asc_lo(hi);
692 p = pack_hex_byte(p, lo);
693 }
694 else if (lo > 0x0f)
695 p = pack_hex_byte(p, lo);
696 else
697 *p++ = hex_asc_lo(lo);
698 needcolon = true;
699 }
700
701 if (useIPv4) {
702 if (needcolon)
703 *p++ = ':';
704 p = ip4_string(p, &in6.s6_addr[12], "I4");
705 }
706 *p = '\0';
707
708 return p;
709 }
710
711 static noinline_for_stack
712 char *ip6_string(char *p, const char *addr, const char *fmt)
713 {
714 int i;
715
716 for (i = 0; i < 8; i++) {
717 p = pack_hex_byte(p, *addr++);
718 p = pack_hex_byte(p, *addr++);
719 if (fmt[0] == 'I' && i != 7)
720 *p++ = ':';
721 }
722 *p = '\0';
723
724 return p;
725 }
726
727 static noinline_for_stack
728 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
729 struct printf_spec spec, const char *fmt)
730 {
731 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
732
733 if (fmt[0] == 'I' && fmt[2] == 'c')
734 ip6_compressed_string(ip6_addr, addr);
735 else
736 ip6_string(ip6_addr, addr, fmt);
737
738 return string(buf, end, ip6_addr, spec);
739 }
740
741 static noinline_for_stack
742 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
743 struct printf_spec spec, const char *fmt)
744 {
745 char ip4_addr[sizeof("255.255.255.255")];
746
747 ip4_string(ip4_addr, addr, fmt);
748
749 return string(buf, end, ip4_addr, spec);
750 }
751
752 static noinline_for_stack
753 char *uuid_string(char *buf, char *end, const u8 *addr,
754 struct printf_spec spec, const char *fmt)
755 {
756 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
757 char *p = uuid;
758 int i;
759 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
760 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
761 const u8 *index = be;
762 bool uc = false;
763
764 switch (*(++fmt)) {
765 case 'L':
766 uc = true; /* fall-through */
767 case 'l':
768 index = le;
769 break;
770 case 'B':
771 uc = true;
772 break;
773 }
774
775 for (i = 0; i < 16; i++) {
776 p = pack_hex_byte(p, addr[index[i]]);
777 switch (i) {
778 case 3:
779 case 5:
780 case 7:
781 case 9:
782 *p++ = '-';
783 break;
784 }
785 }
786
787 *p = 0;
788
789 if (uc) {
790 p = uuid;
791 do {
792 *p = toupper(*p);
793 } while (*(++p));
794 }
795
796 return string(buf, end, uuid, spec);
797 }
798
799 int kptr_restrict __read_mostly;
800
801 /*
802 * Show a '%p' thing. A kernel extension is that the '%p' is followed
803 * by an extra set of alphanumeric characters that are extended format
804 * specifiers.
805 *
806 * Right now we handle:
807 *
808 * - 'F' For symbolic function descriptor pointers with offset
809 * - 'f' For simple symbolic function names without offset
810 * - 'S' For symbolic direct pointers with offset
811 * - 's' For symbolic direct pointers without offset
812 * - 'B' For backtraced symbolic direct pointers with offset
813 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
814 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
815 * - 'M' For a 6-byte MAC address, it prints the address in the
816 * usual colon-separated hex notation
817 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
818 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
819 * with a dash-separated hex notation
820 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
821 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
822 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
823 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
824 * IPv6 omits the colons (01020304...0f)
825 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
826 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
827 * - 'I6c' for IPv6 addresses printed as specified by
828 * http://tools.ietf.org/html/rfc5952
829 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
830 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
831 * Options for %pU are:
832 * b big endian lower case hex (default)
833 * B big endian UPPER case hex
834 * l little endian lower case hex
835 * L little endian UPPER case hex
836 * big endian output byte order is:
837 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
838 * little endian output byte order is:
839 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
840 * - 'V' For a struct va_format which contains a format string * and va_list *,
841 * call vsnprintf(->format, *->va_list).
842 * Implements a "recursive vsnprintf".
843 * Do not use this feature without some mechanism to verify the
844 * correctness of the format string and va_list arguments.
845 * - 'K' For a kernel pointer that should be hidden from unprivileged users
846 *
847 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
848 * function pointers are really function descriptors, which contain a
849 * pointer to the real address.
850 */
851 static noinline_for_stack
852 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
853 struct printf_spec spec)
854 {
855 if (!ptr && *fmt != 'K') {
856 /*
857 * Print (null) with the same width as a pointer so it makes
858 * tabular output look nice.
859 */
860 if (spec.field_width == -1)
861 spec.field_width = 2 * sizeof(void *);
862 return string(buf, end, "(null)", spec);
863 }
864
865 switch (*fmt) {
866 case 'F':
867 case 'f':
868 ptr = dereference_function_descriptor(ptr);
869 /* Fallthrough */
870 case 'S':
871 case 's':
872 case 'B':
873 return symbol_string(buf, end, ptr, spec, *fmt);
874 case 'R':
875 case 'r':
876 return resource_string(buf, end, ptr, spec, fmt);
877 case 'M': /* Colon separated: 00:01:02:03:04:05 */
878 case 'm': /* Contiguous: 000102030405 */
879 /* [mM]F (FDDI, bit reversed) */
880 return mac_address_string(buf, end, ptr, spec, fmt);
881 case 'I': /* Formatted IP supported
882 * 4: 1.2.3.4
883 * 6: 0001:0203:...:0708
884 * 6c: 1::708 or 1::1.2.3.4
885 */
886 case 'i': /* Contiguous:
887 * 4: 001.002.003.004
888 * 6: 000102...0f
889 */
890 switch (fmt[1]) {
891 case '6':
892 return ip6_addr_string(buf, end, ptr, spec, fmt);
893 case '4':
894 return ip4_addr_string(buf, end, ptr, spec, fmt);
895 }
896 break;
897 case 'U':
898 return uuid_string(buf, end, ptr, spec, fmt);
899 case 'V':
900 return buf + vsnprintf(buf, end > buf ? end - buf : 0,
901 ((struct va_format *)ptr)->fmt,
902 *(((struct va_format *)ptr)->va));
903 case 'K':
904 /*
905 * %pK cannot be used in IRQ context because its test
906 * for CAP_SYSLOG would be meaningless.
907 */
908 if (in_irq() || in_serving_softirq() || in_nmi()) {
909 if (spec.field_width == -1)
910 spec.field_width = 2 * sizeof(void *);
911 return string(buf, end, "pK-error", spec);
912 }
913 if (!((kptr_restrict == 0) ||
914 (kptr_restrict == 1 &&
915 has_capability_noaudit(current, CAP_SYSLOG))))
916 ptr = NULL;
917 break;
918 }
919 spec.flags |= SMALL;
920 if (spec.field_width == -1) {
921 spec.field_width = 2 * sizeof(void *);
922 spec.flags |= ZEROPAD;
923 }
924 spec.base = 16;
925
926 return number(buf, end, (unsigned long) ptr, spec);
927 }
928
929 /*
930 * Helper function to decode printf style format.
931 * Each call decode a token from the format and return the
932 * number of characters read (or likely the delta where it wants
933 * to go on the next call).
934 * The decoded token is returned through the parameters
935 *
936 * 'h', 'l', or 'L' for integer fields
937 * 'z' support added 23/7/1999 S.H.
938 * 'z' changed to 'Z' --davidm 1/25/99
939 * 't' added for ptrdiff_t
940 *
941 * @fmt: the format string
942 * @type of the token returned
943 * @flags: various flags such as +, -, # tokens..
944 * @field_width: overwritten width
945 * @base: base of the number (octal, hex, ...)
946 * @precision: precision of a number
947 * @qualifier: qualifier of a number (long, size_t, ...)
948 */
949 static noinline_for_stack
950 int format_decode(const char *fmt, struct printf_spec *spec)
951 {
952 const char *start = fmt;
953
954 /* we finished early by reading the field width */
955 if (spec->type == FORMAT_TYPE_WIDTH) {
956 if (spec->field_width < 0) {
957 spec->field_width = -spec->field_width;
958 spec->flags |= LEFT;
959 }
960 spec->type = FORMAT_TYPE_NONE;
961 goto precision;
962 }
963
964 /* we finished early by reading the precision */
965 if (spec->type == FORMAT_TYPE_PRECISION) {
966 if (spec->precision < 0)
967 spec->precision = 0;
968
969 spec->type = FORMAT_TYPE_NONE;
970 goto qualifier;
971 }
972
973 /* By default */
974 spec->type = FORMAT_TYPE_NONE;
975
976 for (; *fmt ; ++fmt) {
977 if (*fmt == '%')
978 break;
979 }
980
981 /* Return the current non-format string */
982 if (fmt != start || !*fmt)
983 return fmt - start;
984
985 /* Process flags */
986 spec->flags = 0;
987
988 while (1) { /* this also skips first '%' */
989 bool found = true;
990
991 ++fmt;
992
993 switch (*fmt) {
994 case '-': spec->flags |= LEFT; break;
995 case '+': spec->flags |= PLUS; break;
996 case ' ': spec->flags |= SPACE; break;
997 case '#': spec->flags |= SPECIAL; break;
998 case '0': spec->flags |= ZEROPAD; break;
999 default: found = false;
1000 }
1001
1002 if (!found)
1003 break;
1004 }
1005
1006 /* get field width */
1007 spec->field_width = -1;
1008
1009 if (isdigit(*fmt))
1010 spec->field_width = skip_atoi(&fmt);
1011 else if (*fmt == '*') {
1012 /* it's the next argument */
1013 spec->type = FORMAT_TYPE_WIDTH;
1014 return ++fmt - start;
1015 }
1016
1017 precision:
1018 /* get the precision */
1019 spec->precision = -1;
1020 if (*fmt == '.') {
1021 ++fmt;
1022 if (isdigit(*fmt)) {
1023 spec->precision = skip_atoi(&fmt);
1024 if (spec->precision < 0)
1025 spec->precision = 0;
1026 } else if (*fmt == '*') {
1027 /* it's the next argument */
1028 spec->type = FORMAT_TYPE_PRECISION;
1029 return ++fmt - start;
1030 }
1031 }
1032
1033 qualifier:
1034 /* get the conversion qualifier */
1035 spec->qualifier = -1;
1036 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1037 _tolower(*fmt) == 'z' || *fmt == 't') {
1038 spec->qualifier = *fmt++;
1039 if (unlikely(spec->qualifier == *fmt)) {
1040 if (spec->qualifier == 'l') {
1041 spec->qualifier = 'L';
1042 ++fmt;
1043 } else if (spec->qualifier == 'h') {
1044 spec->qualifier = 'H';
1045 ++fmt;
1046 }
1047 }
1048 }
1049
1050 /* default base */
1051 spec->base = 10;
1052 switch (*fmt) {
1053 case 'c':
1054 spec->type = FORMAT_TYPE_CHAR;
1055 return ++fmt - start;
1056
1057 case 's':
1058 spec->type = FORMAT_TYPE_STR;
1059 return ++fmt - start;
1060
1061 case 'p':
1062 spec->type = FORMAT_TYPE_PTR;
1063 return fmt - start;
1064 /* skip alnum */
1065
1066 case 'n':
1067 spec->type = FORMAT_TYPE_NRCHARS;
1068 return ++fmt - start;
1069
1070 case '%':
1071 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1072 return ++fmt - start;
1073
1074 /* integer number formats - set up the flags and "break" */
1075 case 'o':
1076 spec->base = 8;
1077 break;
1078
1079 case 'x':
1080 spec->flags |= SMALL;
1081
1082 case 'X':
1083 spec->base = 16;
1084 break;
1085
1086 case 'd':
1087 case 'i':
1088 spec->flags |= SIGN;
1089 case 'u':
1090 break;
1091
1092 default:
1093 spec->type = FORMAT_TYPE_INVALID;
1094 return fmt - start;
1095 }
1096
1097 if (spec->qualifier == 'L')
1098 spec->type = FORMAT_TYPE_LONG_LONG;
1099 else if (spec->qualifier == 'l') {
1100 if (spec->flags & SIGN)
1101 spec->type = FORMAT_TYPE_LONG;
1102 else
1103 spec->type = FORMAT_TYPE_ULONG;
1104 } else if (_tolower(spec->qualifier) == 'z') {
1105 spec->type = FORMAT_TYPE_SIZE_T;
1106 } else if (spec->qualifier == 't') {
1107 spec->type = FORMAT_TYPE_PTRDIFF;
1108 } else if (spec->qualifier == 'H') {
1109 if (spec->flags & SIGN)
1110 spec->type = FORMAT_TYPE_BYTE;
1111 else
1112 spec->type = FORMAT_TYPE_UBYTE;
1113 } else if (spec->qualifier == 'h') {
1114 if (spec->flags & SIGN)
1115 spec->type = FORMAT_TYPE_SHORT;
1116 else
1117 spec->type = FORMAT_TYPE_USHORT;
1118 } else {
1119 if (spec->flags & SIGN)
1120 spec->type = FORMAT_TYPE_INT;
1121 else
1122 spec->type = FORMAT_TYPE_UINT;
1123 }
1124
1125 return ++fmt - start;
1126 }
1127
1128 /**
1129 * vsnprintf - Format a string and place it in a buffer
1130 * @buf: The buffer to place the result into
1131 * @size: The size of the buffer, including the trailing null space
1132 * @fmt: The format string to use
1133 * @args: Arguments for the format string
1134 *
1135 * This function follows C99 vsnprintf, but has some extensions:
1136 * %pS output the name of a text symbol with offset
1137 * %ps output the name of a text symbol without offset
1138 * %pF output the name of a function pointer with its offset
1139 * %pf output the name of a function pointer without its offset
1140 * %pB output the name of a backtrace symbol with its offset
1141 * %pR output the address range in a struct resource with decoded flags
1142 * %pr output the address range in a struct resource with raw flags
1143 * %pM output a 6-byte MAC address with colons
1144 * %pm output a 6-byte MAC address without colons
1145 * %pI4 print an IPv4 address without leading zeros
1146 * %pi4 print an IPv4 address with leading zeros
1147 * %pI6 print an IPv6 address with colons
1148 * %pi6 print an IPv6 address without colons
1149 * %pI6c print an IPv6 address as specified by RFC 5952
1150 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1151 * case.
1152 * %n is ignored
1153 *
1154 * The return value is the number of characters which would
1155 * be generated for the given input, excluding the trailing
1156 * '\0', as per ISO C99. If you want to have the exact
1157 * number of characters written into @buf as return value
1158 * (not including the trailing '\0'), use vscnprintf(). If the
1159 * return is greater than or equal to @size, the resulting
1160 * string is truncated.
1161 *
1162 * If you're not already dealing with a va_list consider using snprintf().
1163 */
1164 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1165 {
1166 unsigned long long num;
1167 char *str, *end;
1168 struct printf_spec spec = {0};
1169
1170 /* Reject out-of-range values early. Large positive sizes are
1171 used for unknown buffer sizes. */
1172 if (WARN_ON_ONCE((int) size < 0))
1173 return 0;
1174
1175 str = buf;
1176 end = buf + size;
1177
1178 /* Make sure end is always >= buf */
1179 if (end < buf) {
1180 end = ((void *)-1);
1181 size = end - buf;
1182 }
1183
1184 while (*fmt) {
1185 const char *old_fmt = fmt;
1186 int read = format_decode(fmt, &spec);
1187
1188 fmt += read;
1189
1190 switch (spec.type) {
1191 case FORMAT_TYPE_NONE: {
1192 int copy = read;
1193 if (str < end) {
1194 if (copy > end - str)
1195 copy = end - str;
1196 memcpy(str, old_fmt, copy);
1197 }
1198 str += read;
1199 break;
1200 }
1201
1202 case FORMAT_TYPE_WIDTH:
1203 spec.field_width = va_arg(args, int);
1204 break;
1205
1206 case FORMAT_TYPE_PRECISION:
1207 spec.precision = va_arg(args, int);
1208 break;
1209
1210 case FORMAT_TYPE_CHAR: {
1211 char c;
1212
1213 if (!(spec.flags & LEFT)) {
1214 while (--spec.field_width > 0) {
1215 if (str < end)
1216 *str = ' ';
1217 ++str;
1218
1219 }
1220 }
1221 c = (unsigned char) va_arg(args, int);
1222 if (str < end)
1223 *str = c;
1224 ++str;
1225 while (--spec.field_width > 0) {
1226 if (str < end)
1227 *str = ' ';
1228 ++str;
1229 }
1230 break;
1231 }
1232
1233 case FORMAT_TYPE_STR:
1234 str = string(str, end, va_arg(args, char *), spec);
1235 break;
1236
1237 case FORMAT_TYPE_PTR:
1238 str = pointer(fmt+1, str, end, va_arg(args, void *),
1239 spec);
1240 while (isalnum(*fmt))
1241 fmt++;
1242 break;
1243
1244 case FORMAT_TYPE_PERCENT_CHAR:
1245 if (str < end)
1246 *str = '%';
1247 ++str;
1248 break;
1249
1250 case FORMAT_TYPE_INVALID:
1251 if (str < end)
1252 *str = '%';
1253 ++str;
1254 break;
1255
1256 case FORMAT_TYPE_NRCHARS: {
1257 u8 qualifier = spec.qualifier;
1258
1259 if (qualifier == 'l') {
1260 long *ip = va_arg(args, long *);
1261 *ip = (str - buf);
1262 } else if (_tolower(qualifier) == 'z') {
1263 size_t *ip = va_arg(args, size_t *);
1264 *ip = (str - buf);
1265 } else {
1266 int *ip = va_arg(args, int *);
1267 *ip = (str - buf);
1268 }
1269 break;
1270 }
1271
1272 default:
1273 switch (spec.type) {
1274 case FORMAT_TYPE_LONG_LONG:
1275 num = va_arg(args, long long);
1276 break;
1277 case FORMAT_TYPE_ULONG:
1278 num = va_arg(args, unsigned long);
1279 break;
1280 case FORMAT_TYPE_LONG:
1281 num = va_arg(args, long);
1282 break;
1283 case FORMAT_TYPE_SIZE_T:
1284 num = va_arg(args, size_t);
1285 break;
1286 case FORMAT_TYPE_PTRDIFF:
1287 num = va_arg(args, ptrdiff_t);
1288 break;
1289 case FORMAT_TYPE_UBYTE:
1290 num = (unsigned char) va_arg(args, int);
1291 break;
1292 case FORMAT_TYPE_BYTE:
1293 num = (signed char) va_arg(args, int);
1294 break;
1295 case FORMAT_TYPE_USHORT:
1296 num = (unsigned short) va_arg(args, int);
1297 break;
1298 case FORMAT_TYPE_SHORT:
1299 num = (short) va_arg(args, int);
1300 break;
1301 case FORMAT_TYPE_INT:
1302 num = (int) va_arg(args, int);
1303 break;
1304 default:
1305 num = va_arg(args, unsigned int);
1306 }
1307
1308 str = number(str, end, num, spec);
1309 }
1310 }
1311
1312 if (size > 0) {
1313 if (str < end)
1314 *str = '\0';
1315 else
1316 end[-1] = '\0';
1317 }
1318
1319 /* the trailing null byte doesn't count towards the total */
1320 return str-buf;
1321
1322 }
1323 EXPORT_SYMBOL(vsnprintf);
1324
1325 /**
1326 * vscnprintf - Format a string and place it in a buffer
1327 * @buf: The buffer to place the result into
1328 * @size: The size of the buffer, including the trailing null space
1329 * @fmt: The format string to use
1330 * @args: Arguments for the format string
1331 *
1332 * The return value is the number of characters which have been written into
1333 * the @buf not including the trailing '\0'. If @size is == 0 the function
1334 * returns 0.
1335 *
1336 * If you're not already dealing with a va_list consider using scnprintf().
1337 *
1338 * See the vsnprintf() documentation for format string extensions over C99.
1339 */
1340 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1341 {
1342 int i;
1343
1344 i = vsnprintf(buf, size, fmt, args);
1345
1346 if (likely(i < size))
1347 return i;
1348 if (size != 0)
1349 return size - 1;
1350 return 0;
1351 }
1352 EXPORT_SYMBOL(vscnprintf);
1353
1354 /**
1355 * snprintf - Format a string and place it in a buffer
1356 * @buf: The buffer to place the result into
1357 * @size: The size of the buffer, including the trailing null space
1358 * @fmt: The format string to use
1359 * @...: Arguments for the format string
1360 *
1361 * The return value is the number of characters which would be
1362 * generated for the given input, excluding the trailing null,
1363 * as per ISO C99. If the return is greater than or equal to
1364 * @size, the resulting string is truncated.
1365 *
1366 * See the vsnprintf() documentation for format string extensions over C99.
1367 */
1368 int snprintf(char *buf, size_t size, const char *fmt, ...)
1369 {
1370 va_list args;
1371 int i;
1372
1373 va_start(args, fmt);
1374 i = vsnprintf(buf, size, fmt, args);
1375 va_end(args);
1376
1377 return i;
1378 }
1379 EXPORT_SYMBOL(snprintf);
1380
1381 /**
1382 * scnprintf - Format a string and place it in a buffer
1383 * @buf: The buffer to place the result into
1384 * @size: The size of the buffer, including the trailing null space
1385 * @fmt: The format string to use
1386 * @...: Arguments for the format string
1387 *
1388 * The return value is the number of characters written into @buf not including
1389 * the trailing '\0'. If @size is == 0 the function returns 0.
1390 */
1391
1392 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1393 {
1394 va_list args;
1395 int i;
1396
1397 va_start(args, fmt);
1398 i = vscnprintf(buf, size, fmt, args);
1399 va_end(args);
1400
1401 return i;
1402 }
1403 EXPORT_SYMBOL(scnprintf);
1404
1405 /**
1406 * vsprintf - Format a string and place it in a buffer
1407 * @buf: The buffer to place the result into
1408 * @fmt: The format string to use
1409 * @args: Arguments for the format string
1410 *
1411 * The function returns the number of characters written
1412 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1413 * buffer overflows.
1414 *
1415 * If you're not already dealing with a va_list consider using sprintf().
1416 *
1417 * See the vsnprintf() documentation for format string extensions over C99.
1418 */
1419 int vsprintf(char *buf, const char *fmt, va_list args)
1420 {
1421 return vsnprintf(buf, INT_MAX, fmt, args);
1422 }
1423 EXPORT_SYMBOL(vsprintf);
1424
1425 /**
1426 * sprintf - Format a string and place it in a buffer
1427 * @buf: The buffer to place the result into
1428 * @fmt: The format string to use
1429 * @...: Arguments for the format string
1430 *
1431 * The function returns the number of characters written
1432 * into @buf. Use snprintf() or scnprintf() in order to avoid
1433 * buffer overflows.
1434 *
1435 * See the vsnprintf() documentation for format string extensions over C99.
1436 */
1437 int sprintf(char *buf, const char *fmt, ...)
1438 {
1439 va_list args;
1440 int i;
1441
1442 va_start(args, fmt);
1443 i = vsnprintf(buf, INT_MAX, fmt, args);
1444 va_end(args);
1445
1446 return i;
1447 }
1448 EXPORT_SYMBOL(sprintf);
1449
1450 #ifdef CONFIG_BINARY_PRINTF
1451 /*
1452 * bprintf service:
1453 * vbin_printf() - VA arguments to binary data
1454 * bstr_printf() - Binary data to text string
1455 */
1456
1457 /**
1458 * vbin_printf - Parse a format string and place args' binary value in a buffer
1459 * @bin_buf: The buffer to place args' binary value
1460 * @size: The size of the buffer(by words(32bits), not characters)
1461 * @fmt: The format string to use
1462 * @args: Arguments for the format string
1463 *
1464 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1465 * is skiped.
1466 *
1467 * The return value is the number of words(32bits) which would be generated for
1468 * the given input.
1469 *
1470 * NOTE:
1471 * If the return value is greater than @size, the resulting bin_buf is NOT
1472 * valid for bstr_printf().
1473 */
1474 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1475 {
1476 struct printf_spec spec = {0};
1477 char *str, *end;
1478
1479 str = (char *)bin_buf;
1480 end = (char *)(bin_buf + size);
1481
1482 #define save_arg(type) \
1483 do { \
1484 if (sizeof(type) == 8) { \
1485 unsigned long long value; \
1486 str = PTR_ALIGN(str, sizeof(u32)); \
1487 value = va_arg(args, unsigned long long); \
1488 if (str + sizeof(type) <= end) { \
1489 *(u32 *)str = *(u32 *)&value; \
1490 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1491 } \
1492 } else { \
1493 unsigned long value; \
1494 str = PTR_ALIGN(str, sizeof(type)); \
1495 value = va_arg(args, int); \
1496 if (str + sizeof(type) <= end) \
1497 *(typeof(type) *)str = (type)value; \
1498 } \
1499 str += sizeof(type); \
1500 } while (0)
1501
1502 while (*fmt) {
1503 int read = format_decode(fmt, &spec);
1504
1505 fmt += read;
1506
1507 switch (spec.type) {
1508 case FORMAT_TYPE_NONE:
1509 case FORMAT_TYPE_INVALID:
1510 case FORMAT_TYPE_PERCENT_CHAR:
1511 break;
1512
1513 case FORMAT_TYPE_WIDTH:
1514 case FORMAT_TYPE_PRECISION:
1515 save_arg(int);
1516 break;
1517
1518 case FORMAT_TYPE_CHAR:
1519 save_arg(char);
1520 break;
1521
1522 case FORMAT_TYPE_STR: {
1523 const char *save_str = va_arg(args, char *);
1524 size_t len;
1525
1526 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1527 || (unsigned long)save_str < PAGE_SIZE)
1528 save_str = "(null)";
1529 len = strlen(save_str) + 1;
1530 if (str + len < end)
1531 memcpy(str, save_str, len);
1532 str += len;
1533 break;
1534 }
1535
1536 case FORMAT_TYPE_PTR:
1537 save_arg(void *);
1538 /* skip all alphanumeric pointer suffixes */
1539 while (isalnum(*fmt))
1540 fmt++;
1541 break;
1542
1543 case FORMAT_TYPE_NRCHARS: {
1544 /* skip %n 's argument */
1545 u8 qualifier = spec.qualifier;
1546 void *skip_arg;
1547 if (qualifier == 'l')
1548 skip_arg = va_arg(args, long *);
1549 else if (_tolower(qualifier) == 'z')
1550 skip_arg = va_arg(args, size_t *);
1551 else
1552 skip_arg = va_arg(args, int *);
1553 break;
1554 }
1555
1556 default:
1557 switch (spec.type) {
1558
1559 case FORMAT_TYPE_LONG_LONG:
1560 save_arg(long long);
1561 break;
1562 case FORMAT_TYPE_ULONG:
1563 case FORMAT_TYPE_LONG:
1564 save_arg(unsigned long);
1565 break;
1566 case FORMAT_TYPE_SIZE_T:
1567 save_arg(size_t);
1568 break;
1569 case FORMAT_TYPE_PTRDIFF:
1570 save_arg(ptrdiff_t);
1571 break;
1572 case FORMAT_TYPE_UBYTE:
1573 case FORMAT_TYPE_BYTE:
1574 save_arg(char);
1575 break;
1576 case FORMAT_TYPE_USHORT:
1577 case FORMAT_TYPE_SHORT:
1578 save_arg(short);
1579 break;
1580 default:
1581 save_arg(int);
1582 }
1583 }
1584 }
1585
1586 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1587 #undef save_arg
1588 }
1589 EXPORT_SYMBOL_GPL(vbin_printf);
1590
1591 /**
1592 * bstr_printf - Format a string from binary arguments and place it in a buffer
1593 * @buf: The buffer to place the result into
1594 * @size: The size of the buffer, including the trailing null space
1595 * @fmt: The format string to use
1596 * @bin_buf: Binary arguments for the format string
1597 *
1598 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1599 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1600 * a binary buffer that generated by vbin_printf.
1601 *
1602 * The format follows C99 vsnprintf, but has some extensions:
1603 * see vsnprintf comment for details.
1604 *
1605 * The return value is the number of characters which would
1606 * be generated for the given input, excluding the trailing
1607 * '\0', as per ISO C99. If you want to have the exact
1608 * number of characters written into @buf as return value
1609 * (not including the trailing '\0'), use vscnprintf(). If the
1610 * return is greater than or equal to @size, the resulting
1611 * string is truncated.
1612 */
1613 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1614 {
1615 struct printf_spec spec = {0};
1616 char *str, *end;
1617 const char *args = (const char *)bin_buf;
1618
1619 if (WARN_ON_ONCE((int) size < 0))
1620 return 0;
1621
1622 str = buf;
1623 end = buf + size;
1624
1625 #define get_arg(type) \
1626 ({ \
1627 typeof(type) value; \
1628 if (sizeof(type) == 8) { \
1629 args = PTR_ALIGN(args, sizeof(u32)); \
1630 *(u32 *)&value = *(u32 *)args; \
1631 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1632 } else { \
1633 args = PTR_ALIGN(args, sizeof(type)); \
1634 value = *(typeof(type) *)args; \
1635 } \
1636 args += sizeof(type); \
1637 value; \
1638 })
1639
1640 /* Make sure end is always >= buf */
1641 if (end < buf) {
1642 end = ((void *)-1);
1643 size = end - buf;
1644 }
1645
1646 while (*fmt) {
1647 const char *old_fmt = fmt;
1648 int read = format_decode(fmt, &spec);
1649
1650 fmt += read;
1651
1652 switch (spec.type) {
1653 case FORMAT_TYPE_NONE: {
1654 int copy = read;
1655 if (str < end) {
1656 if (copy > end - str)
1657 copy = end - str;
1658 memcpy(str, old_fmt, copy);
1659 }
1660 str += read;
1661 break;
1662 }
1663
1664 case FORMAT_TYPE_WIDTH:
1665 spec.field_width = get_arg(int);
1666 break;
1667
1668 case FORMAT_TYPE_PRECISION:
1669 spec.precision = get_arg(int);
1670 break;
1671
1672 case FORMAT_TYPE_CHAR: {
1673 char c;
1674
1675 if (!(spec.flags & LEFT)) {
1676 while (--spec.field_width > 0) {
1677 if (str < end)
1678 *str = ' ';
1679 ++str;
1680 }
1681 }
1682 c = (unsigned char) get_arg(char);
1683 if (str < end)
1684 *str = c;
1685 ++str;
1686 while (--spec.field_width > 0) {
1687 if (str < end)
1688 *str = ' ';
1689 ++str;
1690 }
1691 break;
1692 }
1693
1694 case FORMAT_TYPE_STR: {
1695 const char *str_arg = args;
1696 args += strlen(str_arg) + 1;
1697 str = string(str, end, (char *)str_arg, spec);
1698 break;
1699 }
1700
1701 case FORMAT_TYPE_PTR:
1702 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1703 while (isalnum(*fmt))
1704 fmt++;
1705 break;
1706
1707 case FORMAT_TYPE_PERCENT_CHAR:
1708 case FORMAT_TYPE_INVALID:
1709 if (str < end)
1710 *str = '%';
1711 ++str;
1712 break;
1713
1714 case FORMAT_TYPE_NRCHARS:
1715 /* skip */
1716 break;
1717
1718 default: {
1719 unsigned long long num;
1720
1721 switch (spec.type) {
1722
1723 case FORMAT_TYPE_LONG_LONG:
1724 num = get_arg(long long);
1725 break;
1726 case FORMAT_TYPE_ULONG:
1727 case FORMAT_TYPE_LONG:
1728 num = get_arg(unsigned long);
1729 break;
1730 case FORMAT_TYPE_SIZE_T:
1731 num = get_arg(size_t);
1732 break;
1733 case FORMAT_TYPE_PTRDIFF:
1734 num = get_arg(ptrdiff_t);
1735 break;
1736 case FORMAT_TYPE_UBYTE:
1737 num = get_arg(unsigned char);
1738 break;
1739 case FORMAT_TYPE_BYTE:
1740 num = get_arg(signed char);
1741 break;
1742 case FORMAT_TYPE_USHORT:
1743 num = get_arg(unsigned short);
1744 break;
1745 case FORMAT_TYPE_SHORT:
1746 num = get_arg(short);
1747 break;
1748 case FORMAT_TYPE_UINT:
1749 num = get_arg(unsigned int);
1750 break;
1751 default:
1752 num = get_arg(int);
1753 }
1754
1755 str = number(str, end, num, spec);
1756 } /* default: */
1757 } /* switch(spec.type) */
1758 } /* while(*fmt) */
1759
1760 if (size > 0) {
1761 if (str < end)
1762 *str = '\0';
1763 else
1764 end[-1] = '\0';
1765 }
1766
1767 #undef get_arg
1768
1769 /* the trailing null byte doesn't count towards the total */
1770 return str - buf;
1771 }
1772 EXPORT_SYMBOL_GPL(bstr_printf);
1773
1774 /**
1775 * bprintf - Parse a format string and place args' binary value in a buffer
1776 * @bin_buf: The buffer to place args' binary value
1777 * @size: The size of the buffer(by words(32bits), not characters)
1778 * @fmt: The format string to use
1779 * @...: Arguments for the format string
1780 *
1781 * The function returns the number of words(u32) written
1782 * into @bin_buf.
1783 */
1784 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1785 {
1786 va_list args;
1787 int ret;
1788
1789 va_start(args, fmt);
1790 ret = vbin_printf(bin_buf, size, fmt, args);
1791 va_end(args);
1792
1793 return ret;
1794 }
1795 EXPORT_SYMBOL_GPL(bprintf);
1796
1797 #endif /* CONFIG_BINARY_PRINTF */
1798
1799 /**
1800 * vsscanf - Unformat a buffer into a list of arguments
1801 * @buf: input buffer
1802 * @fmt: format of buffer
1803 * @args: arguments
1804 */
1805 int vsscanf(const char *buf, const char *fmt, va_list args)
1806 {
1807 const char *str = buf;
1808 char *next;
1809 char digit;
1810 int num = 0;
1811 u8 qualifier;
1812 u8 base;
1813 s16 field_width;
1814 bool is_sign;
1815
1816 while (*fmt && *str) {
1817 /* skip any white space in format */
1818 /* white space in format matchs any amount of
1819 * white space, including none, in the input.
1820 */
1821 if (isspace(*fmt)) {
1822 fmt = skip_spaces(++fmt);
1823 str = skip_spaces(str);
1824 }
1825
1826 /* anything that is not a conversion must match exactly */
1827 if (*fmt != '%' && *fmt) {
1828 if (*fmt++ != *str++)
1829 break;
1830 continue;
1831 }
1832
1833 if (!*fmt)
1834 break;
1835 ++fmt;
1836
1837 /* skip this conversion.
1838 * advance both strings to next white space
1839 */
1840 if (*fmt == '*') {
1841 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1842 fmt++;
1843 while (!isspace(*str) && *str)
1844 str++;
1845 continue;
1846 }
1847
1848 /* get field width */
1849 field_width = -1;
1850 if (isdigit(*fmt))
1851 field_width = skip_atoi(&fmt);
1852
1853 /* get conversion qualifier */
1854 qualifier = -1;
1855 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1856 _tolower(*fmt) == 'z') {
1857 qualifier = *fmt++;
1858 if (unlikely(qualifier == *fmt)) {
1859 if (qualifier == 'h') {
1860 qualifier = 'H';
1861 fmt++;
1862 } else if (qualifier == 'l') {
1863 qualifier = 'L';
1864 fmt++;
1865 }
1866 }
1867 }
1868
1869 if (!*fmt || !*str)
1870 break;
1871
1872 base = 10;
1873 is_sign = 0;
1874
1875 switch (*fmt++) {
1876 case 'c':
1877 {
1878 char *s = (char *)va_arg(args, char*);
1879 if (field_width == -1)
1880 field_width = 1;
1881 do {
1882 *s++ = *str++;
1883 } while (--field_width > 0 && *str);
1884 num++;
1885 }
1886 continue;
1887 case 's':
1888 {
1889 char *s = (char *)va_arg(args, char *);
1890 if (field_width == -1)
1891 field_width = SHRT_MAX;
1892 /* first, skip leading white space in buffer */
1893 str = skip_spaces(str);
1894
1895 /* now copy until next white space */
1896 while (*str && !isspace(*str) && field_width--)
1897 *s++ = *str++;
1898 *s = '\0';
1899 num++;
1900 }
1901 continue;
1902 case 'n':
1903 /* return number of characters read so far */
1904 {
1905 int *i = (int *)va_arg(args, int*);
1906 *i = str - buf;
1907 }
1908 continue;
1909 case 'o':
1910 base = 8;
1911 break;
1912 case 'x':
1913 case 'X':
1914 base = 16;
1915 break;
1916 case 'i':
1917 base = 0;
1918 case 'd':
1919 is_sign = 1;
1920 case 'u':
1921 break;
1922 case '%':
1923 /* looking for '%' in str */
1924 if (*str++ != '%')
1925 return num;
1926 continue;
1927 default:
1928 /* invalid format; stop here */
1929 return num;
1930 }
1931
1932 /* have some sort of integer conversion.
1933 * first, skip white space in buffer.
1934 */
1935 str = skip_spaces(str);
1936
1937 digit = *str;
1938 if (is_sign && digit == '-')
1939 digit = *(str + 1);
1940
1941 if (!digit
1942 || (base == 16 && !isxdigit(digit))
1943 || (base == 10 && !isdigit(digit))
1944 || (base == 8 && (!isdigit(digit) || digit > '7'))
1945 || (base == 0 && !isdigit(digit)))
1946 break;
1947
1948 switch (qualifier) {
1949 case 'H': /* that's 'hh' in format */
1950 if (is_sign) {
1951 signed char *s = (signed char *)va_arg(args, signed char *);
1952 *s = (signed char)simple_strtol(str, &next, base);
1953 } else {
1954 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1955 *s = (unsigned char)simple_strtoul(str, &next, base);
1956 }
1957 break;
1958 case 'h':
1959 if (is_sign) {
1960 short *s = (short *)va_arg(args, short *);
1961 *s = (short)simple_strtol(str, &next, base);
1962 } else {
1963 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1964 *s = (unsigned short)simple_strtoul(str, &next, base);
1965 }
1966 break;
1967 case 'l':
1968 if (is_sign) {
1969 long *l = (long *)va_arg(args, long *);
1970 *l = simple_strtol(str, &next, base);
1971 } else {
1972 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1973 *l = simple_strtoul(str, &next, base);
1974 }
1975 break;
1976 case 'L':
1977 if (is_sign) {
1978 long long *l = (long long *)va_arg(args, long long *);
1979 *l = simple_strtoll(str, &next, base);
1980 } else {
1981 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1982 *l = simple_strtoull(str, &next, base);
1983 }
1984 break;
1985 case 'Z':
1986 case 'z':
1987 {
1988 size_t *s = (size_t *)va_arg(args, size_t *);
1989 *s = (size_t)simple_strtoul(str, &next, base);
1990 }
1991 break;
1992 default:
1993 if (is_sign) {
1994 int *i = (int *)va_arg(args, int *);
1995 *i = (int)simple_strtol(str, &next, base);
1996 } else {
1997 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
1998 *i = (unsigned int)simple_strtoul(str, &next, base);
1999 }
2000 break;
2001 }
2002 num++;
2003
2004 if (!next)
2005 break;
2006 str = next;
2007 }
2008
2009 /*
2010 * Now we've come all the way through so either the input string or the
2011 * format ended. In the former case, there can be a %n at the current
2012 * position in the format that needs to be filled.
2013 */
2014 if (*fmt == '%' && *(fmt + 1) == 'n') {
2015 int *p = (int *)va_arg(args, int *);
2016 *p = str - buf;
2017 }
2018
2019 return num;
2020 }
2021 EXPORT_SYMBOL(vsscanf);
2022
2023 /**
2024 * sscanf - Unformat a buffer into a list of arguments
2025 * @buf: input buffer
2026 * @fmt: formatting of buffer
2027 * @...: resulting arguments
2028 */
2029 int sscanf(const char *buf, const char *fmt, ...)
2030 {
2031 va_list args;
2032 int i;
2033
2034 va_start(args, fmt);
2035 i = vsscanf(buf, fmt, args);
2036 va_end(args);
2037
2038 return i;
2039 }
2040 EXPORT_SYMBOL(sscanf);
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