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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
[deliverable/linux.git] / lib / vsprintf.c
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> /* for KSYM_SYMBOL_LEN */
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/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 #include "kstrtox.h"
35
36 /**
37 * simple_strtoull - convert a string to an unsigned long long
38 * @cp: The start of the string
39 * @endp: A pointer to the end of the parsed string will be placed here
40 * @base: The number base to use
41 */
42 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
43 {
44 unsigned long long result;
45 unsigned int rv;
46
47 cp = _parse_integer_fixup_radix(cp, &base);
48 rv = _parse_integer(cp, base, &result);
49 /* FIXME */
50 cp += (rv & ~KSTRTOX_OVERFLOW);
51
52 if (endp)
53 *endp = (char *)cp;
54
55 return result;
56 }
57 EXPORT_SYMBOL(simple_strtoull);
58
59 /**
60 * simple_strtoul - convert a string to an unsigned long
61 * @cp: The start of the string
62 * @endp: A pointer to the end of the parsed string will be placed here
63 * @base: The number base to use
64 */
65 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
66 {
67 return simple_strtoull(cp, endp, base);
68 }
69 EXPORT_SYMBOL(simple_strtoul);
70
71 /**
72 * simple_strtol - convert a string to a signed long
73 * @cp: The start of the string
74 * @endp: A pointer to the end of the parsed string will be placed here
75 * @base: The number base to use
76 */
77 long simple_strtol(const char *cp, char **endp, unsigned int base)
78 {
79 if (*cp == '-')
80 return -simple_strtoul(cp + 1, endp, base);
81
82 return simple_strtoul(cp, endp, base);
83 }
84 EXPORT_SYMBOL(simple_strtol);
85
86 /**
87 * simple_strtoll - convert a string to a signed long long
88 * @cp: The start of the string
89 * @endp: A pointer to the end of the parsed string will be placed here
90 * @base: The number base to use
91 */
92 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
93 {
94 if (*cp == '-')
95 return -simple_strtoull(cp + 1, endp, base);
96
97 return simple_strtoull(cp, endp, base);
98 }
99 EXPORT_SYMBOL(simple_strtoll);
100
101 static noinline_for_stack
102 int skip_atoi(const char **s)
103 {
104 int i = 0;
105
106 while (isdigit(**s))
107 i = i*10 + *((*s)++) - '0';
108
109 return i;
110 }
111
112 /* Decimal conversion is by far the most typical, and is used
113 * for /proc and /sys data. This directly impacts e.g. top performance
114 * with many processes running. We optimize it for speed
115 * using code from
116 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
117 * (with permission from the author, Douglas W. Jones). */
118
119 /* Formats correctly any integer in [0,99999].
120 * Outputs from one to five digits depending on input.
121 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
122 static noinline_for_stack
123 char *put_dec_trunc(char *buf, unsigned q)
124 {
125 unsigned d3, d2, d1, d0;
126 d1 = (q>>4) & 0xf;
127 d2 = (q>>8) & 0xf;
128 d3 = (q>>12);
129
130 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
131 q = (d0 * 0xcd) >> 11;
132 d0 = d0 - 10*q;
133 *buf++ = d0 + '0'; /* least significant digit */
134 d1 = q + 9*d3 + 5*d2 + d1;
135 if (d1 != 0) {
136 q = (d1 * 0xcd) >> 11;
137 d1 = d1 - 10*q;
138 *buf++ = d1 + '0'; /* next digit */
139
140 d2 = q + 2*d2;
141 if ((d2 != 0) || (d3 != 0)) {
142 q = (d2 * 0xd) >> 7;
143 d2 = d2 - 10*q;
144 *buf++ = d2 + '0'; /* next digit */
145
146 d3 = q + 4*d3;
147 if (d3 != 0) {
148 q = (d3 * 0xcd) >> 11;
149 d3 = d3 - 10*q;
150 *buf++ = d3 + '0'; /* next digit */
151 if (q != 0)
152 *buf++ = q + '0'; /* most sign. digit */
153 }
154 }
155 }
156
157 return buf;
158 }
159 /* Same with if's removed. Always emits five digits */
160 static noinline_for_stack
161 char *put_dec_full(char *buf, unsigned q)
162 {
163 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
164 /* but anyway, gcc produces better code with full-sized ints */
165 unsigned d3, d2, d1, d0;
166 d1 = (q>>4) & 0xf;
167 d2 = (q>>8) & 0xf;
168 d3 = (q>>12);
169
170 /*
171 * Possible ways to approx. divide by 10
172 * gcc -O2 replaces multiply with shifts and adds
173 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
174 * (x * 0x67) >> 10: 1100111
175 * (x * 0x34) >> 9: 110100 - same
176 * (x * 0x1a) >> 8: 11010 - same
177 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
178 */
179 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
180 q = (d0 * 0xcd) >> 11;
181 d0 = d0 - 10*q;
182 *buf++ = d0 + '0';
183 d1 = q + 9*d3 + 5*d2 + d1;
184 q = (d1 * 0xcd) >> 11;
185 d1 = d1 - 10*q;
186 *buf++ = d1 + '0';
187
188 d2 = q + 2*d2;
189 q = (d2 * 0xd) >> 7;
190 d2 = d2 - 10*q;
191 *buf++ = d2 + '0';
192
193 d3 = q + 4*d3;
194 q = (d3 * 0xcd) >> 11; /* - shorter code */
195 /* q = (d3 * 0x67) >> 10; - would also work */
196 d3 = d3 - 10*q;
197 *buf++ = d3 + '0';
198 *buf++ = q + '0';
199
200 return buf;
201 }
202 /* No inlining helps gcc to use registers better */
203 static noinline_for_stack
204 char *put_dec(char *buf, unsigned long long num)
205 {
206 while (1) {
207 unsigned rem;
208 if (num < 100000)
209 return put_dec_trunc(buf, num);
210 rem = do_div(num, 100000);
211 buf = put_dec_full(buf, rem);
212 }
213 }
214
215 /*
216 * Convert passed number to decimal string.
217 * Returns the length of string. On buffer overflow, returns 0.
218 *
219 * If speed is not important, use snprintf(). It's easy to read the code.
220 */
221 int num_to_str(char *buf, int size, unsigned long long num)
222 {
223 char tmp[21]; /* Enough for 2^64 in decimal */
224 int idx, len;
225
226 len = put_dec(tmp, num) - tmp;
227
228 if (len > size)
229 return 0;
230 for (idx = 0; idx < len; ++idx)
231 buf[idx] = tmp[len - idx - 1];
232 return len;
233 }
234
235 #define ZEROPAD 1 /* pad with zero */
236 #define SIGN 2 /* unsigned/signed long */
237 #define PLUS 4 /* show plus */
238 #define SPACE 8 /* space if plus */
239 #define LEFT 16 /* left justified */
240 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
241 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
242
243 enum format_type {
244 FORMAT_TYPE_NONE, /* Just a string part */
245 FORMAT_TYPE_WIDTH,
246 FORMAT_TYPE_PRECISION,
247 FORMAT_TYPE_CHAR,
248 FORMAT_TYPE_STR,
249 FORMAT_TYPE_PTR,
250 FORMAT_TYPE_PERCENT_CHAR,
251 FORMAT_TYPE_INVALID,
252 FORMAT_TYPE_LONG_LONG,
253 FORMAT_TYPE_ULONG,
254 FORMAT_TYPE_LONG,
255 FORMAT_TYPE_UBYTE,
256 FORMAT_TYPE_BYTE,
257 FORMAT_TYPE_USHORT,
258 FORMAT_TYPE_SHORT,
259 FORMAT_TYPE_UINT,
260 FORMAT_TYPE_INT,
261 FORMAT_TYPE_NRCHARS,
262 FORMAT_TYPE_SIZE_T,
263 FORMAT_TYPE_PTRDIFF
264 };
265
266 struct printf_spec {
267 u8 type; /* format_type enum */
268 u8 flags; /* flags to number() */
269 u8 base; /* number base, 8, 10 or 16 only */
270 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
271 s16 field_width; /* width of output field */
272 s16 precision; /* # of digits/chars */
273 };
274
275 static noinline_for_stack
276 char *number(char *buf, char *end, unsigned long long num,
277 struct printf_spec spec)
278 {
279 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
280 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
281
282 char tmp[66];
283 char sign;
284 char locase;
285 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
286 int i;
287 bool is_zero = num == 0LL;
288
289 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
290 * produces same digits or (maybe lowercased) letters */
291 locase = (spec.flags & SMALL);
292 if (spec.flags & LEFT)
293 spec.flags &= ~ZEROPAD;
294 sign = 0;
295 if (spec.flags & SIGN) {
296 if ((signed long long)num < 0) {
297 sign = '-';
298 num = -(signed long long)num;
299 spec.field_width--;
300 } else if (spec.flags & PLUS) {
301 sign = '+';
302 spec.field_width--;
303 } else if (spec.flags & SPACE) {
304 sign = ' ';
305 spec.field_width--;
306 }
307 }
308 if (need_pfx) {
309 if (spec.base == 16)
310 spec.field_width -= 2;
311 else if (!is_zero)
312 spec.field_width--;
313 }
314
315 /* generate full string in tmp[], in reverse order */
316 i = 0;
317 if (num == 0)
318 tmp[i++] = '0';
319 /* Generic code, for any base:
320 else do {
321 tmp[i++] = (digits[do_div(num,base)] | locase);
322 } while (num != 0);
323 */
324 else if (spec.base != 10) { /* 8 or 16 */
325 int mask = spec.base - 1;
326 int shift = 3;
327
328 if (spec.base == 16)
329 shift = 4;
330 do {
331 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
332 num >>= shift;
333 } while (num);
334 } else { /* base 10 */
335 i = put_dec(tmp, num) - tmp;
336 }
337
338 /* printing 100 using %2d gives "100", not "00" */
339 if (i > spec.precision)
340 spec.precision = i;
341 /* leading space padding */
342 spec.field_width -= spec.precision;
343 if (!(spec.flags & (ZEROPAD+LEFT))) {
344 while (--spec.field_width >= 0) {
345 if (buf < end)
346 *buf = ' ';
347 ++buf;
348 }
349 }
350 /* sign */
351 if (sign) {
352 if (buf < end)
353 *buf = sign;
354 ++buf;
355 }
356 /* "0x" / "0" prefix */
357 if (need_pfx) {
358 if (spec.base == 16 || !is_zero) {
359 if (buf < end)
360 *buf = '0';
361 ++buf;
362 }
363 if (spec.base == 16) {
364 if (buf < end)
365 *buf = ('X' | locase);
366 ++buf;
367 }
368 }
369 /* zero or space padding */
370 if (!(spec.flags & LEFT)) {
371 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
372 while (--spec.field_width >= 0) {
373 if (buf < end)
374 *buf = c;
375 ++buf;
376 }
377 }
378 /* hmm even more zero padding? */
379 while (i <= --spec.precision) {
380 if (buf < end)
381 *buf = '0';
382 ++buf;
383 }
384 /* actual digits of result */
385 while (--i >= 0) {
386 if (buf < end)
387 *buf = tmp[i];
388 ++buf;
389 }
390 /* trailing space padding */
391 while (--spec.field_width >= 0) {
392 if (buf < end)
393 *buf = ' ';
394 ++buf;
395 }
396
397 return buf;
398 }
399
400 static noinline_for_stack
401 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
402 {
403 int len, i;
404
405 if ((unsigned long)s < PAGE_SIZE)
406 s = "(null)";
407
408 len = strnlen(s, spec.precision);
409
410 if (!(spec.flags & LEFT)) {
411 while (len < spec.field_width--) {
412 if (buf < end)
413 *buf = ' ';
414 ++buf;
415 }
416 }
417 for (i = 0; i < len; ++i) {
418 if (buf < end)
419 *buf = *s;
420 ++buf; ++s;
421 }
422 while (len < spec.field_width--) {
423 if (buf < end)
424 *buf = ' ';
425 ++buf;
426 }
427
428 return buf;
429 }
430
431 static noinline_for_stack
432 char *symbol_string(char *buf, char *end, void *ptr,
433 struct printf_spec spec, char ext)
434 {
435 unsigned long value = (unsigned long) ptr;
436 #ifdef CONFIG_KALLSYMS
437 char sym[KSYM_SYMBOL_LEN];
438 if (ext == 'B')
439 sprint_backtrace(sym, value);
440 else if (ext != 'f' && ext != 's')
441 sprint_symbol(sym, value);
442 else
443 sprint_symbol_no_offset(sym, value);
444
445 return string(buf, end, sym, spec);
446 #else
447 spec.field_width = 2 * sizeof(void *);
448 spec.flags |= SPECIAL | SMALL | ZEROPAD;
449 spec.base = 16;
450
451 return number(buf, end, value, spec);
452 #endif
453 }
454
455 static noinline_for_stack
456 char *resource_string(char *buf, char *end, struct resource *res,
457 struct printf_spec spec, const char *fmt)
458 {
459 #ifndef IO_RSRC_PRINTK_SIZE
460 #define IO_RSRC_PRINTK_SIZE 6
461 #endif
462
463 #ifndef MEM_RSRC_PRINTK_SIZE
464 #define MEM_RSRC_PRINTK_SIZE 10
465 #endif
466 static const struct printf_spec io_spec = {
467 .base = 16,
468 .field_width = IO_RSRC_PRINTK_SIZE,
469 .precision = -1,
470 .flags = SPECIAL | SMALL | ZEROPAD,
471 };
472 static const struct printf_spec mem_spec = {
473 .base = 16,
474 .field_width = MEM_RSRC_PRINTK_SIZE,
475 .precision = -1,
476 .flags = SPECIAL | SMALL | ZEROPAD,
477 };
478 static const struct printf_spec bus_spec = {
479 .base = 16,
480 .field_width = 2,
481 .precision = -1,
482 .flags = SMALL | ZEROPAD,
483 };
484 static const struct printf_spec dec_spec = {
485 .base = 10,
486 .precision = -1,
487 .flags = 0,
488 };
489 static const struct printf_spec str_spec = {
490 .field_width = -1,
491 .precision = 10,
492 .flags = LEFT,
493 };
494 static const struct printf_spec flag_spec = {
495 .base = 16,
496 .precision = -1,
497 .flags = SPECIAL | SMALL,
498 };
499
500 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
501 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
502 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
503 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
504 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
505 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
506 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
507 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
508
509 char *p = sym, *pend = sym + sizeof(sym);
510 int decode = (fmt[0] == 'R') ? 1 : 0;
511 const struct printf_spec *specp;
512
513 *p++ = '[';
514 if (res->flags & IORESOURCE_IO) {
515 p = string(p, pend, "io ", str_spec);
516 specp = &io_spec;
517 } else if (res->flags & IORESOURCE_MEM) {
518 p = string(p, pend, "mem ", str_spec);
519 specp = &mem_spec;
520 } else if (res->flags & IORESOURCE_IRQ) {
521 p = string(p, pend, "irq ", str_spec);
522 specp = &dec_spec;
523 } else if (res->flags & IORESOURCE_DMA) {
524 p = string(p, pend, "dma ", str_spec);
525 specp = &dec_spec;
526 } else if (res->flags & IORESOURCE_BUS) {
527 p = string(p, pend, "bus ", str_spec);
528 specp = &bus_spec;
529 } else {
530 p = string(p, pend, "??? ", str_spec);
531 specp = &mem_spec;
532 decode = 0;
533 }
534 p = number(p, pend, res->start, *specp);
535 if (res->start != res->end) {
536 *p++ = '-';
537 p = number(p, pend, res->end, *specp);
538 }
539 if (decode) {
540 if (res->flags & IORESOURCE_MEM_64)
541 p = string(p, pend, " 64bit", str_spec);
542 if (res->flags & IORESOURCE_PREFETCH)
543 p = string(p, pend, " pref", str_spec);
544 if (res->flags & IORESOURCE_WINDOW)
545 p = string(p, pend, " window", str_spec);
546 if (res->flags & IORESOURCE_DISABLED)
547 p = string(p, pend, " disabled", str_spec);
548 } else {
549 p = string(p, pend, " flags ", str_spec);
550 p = number(p, pend, res->flags, flag_spec);
551 }
552 *p++ = ']';
553 *p = '\0';
554
555 return string(buf, end, sym, spec);
556 }
557
558 static noinline_for_stack
559 char *mac_address_string(char *buf, char *end, u8 *addr,
560 struct printf_spec spec, const char *fmt)
561 {
562 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
563 char *p = mac_addr;
564 int i;
565 char separator;
566
567 if (fmt[1] == 'F') { /* FDDI canonical format */
568 separator = '-';
569 } else {
570 separator = ':';
571 }
572
573 for (i = 0; i < 6; i++) {
574 p = hex_byte_pack(p, addr[i]);
575 if (fmt[0] == 'M' && i != 5)
576 *p++ = separator;
577 }
578 *p = '\0';
579
580 return string(buf, end, mac_addr, spec);
581 }
582
583 static noinline_for_stack
584 char *ip4_string(char *p, const u8 *addr, const char *fmt)
585 {
586 int i;
587 bool leading_zeros = (fmt[0] == 'i');
588 int index;
589 int step;
590
591 switch (fmt[2]) {
592 case 'h':
593 #ifdef __BIG_ENDIAN
594 index = 0;
595 step = 1;
596 #else
597 index = 3;
598 step = -1;
599 #endif
600 break;
601 case 'l':
602 index = 3;
603 step = -1;
604 break;
605 case 'n':
606 case 'b':
607 default:
608 index = 0;
609 step = 1;
610 break;
611 }
612 for (i = 0; i < 4; i++) {
613 char temp[3]; /* hold each IP quad in reverse order */
614 int digits = put_dec_trunc(temp, addr[index]) - temp;
615 if (leading_zeros) {
616 if (digits < 3)
617 *p++ = '0';
618 if (digits < 2)
619 *p++ = '0';
620 }
621 /* reverse the digits in the quad */
622 while (digits--)
623 *p++ = temp[digits];
624 if (i < 3)
625 *p++ = '.';
626 index += step;
627 }
628 *p = '\0';
629
630 return p;
631 }
632
633 static noinline_for_stack
634 char *ip6_compressed_string(char *p, const char *addr)
635 {
636 int i, j, range;
637 unsigned char zerolength[8];
638 int longest = 1;
639 int colonpos = -1;
640 u16 word;
641 u8 hi, lo;
642 bool needcolon = false;
643 bool useIPv4;
644 struct in6_addr in6;
645
646 memcpy(&in6, addr, sizeof(struct in6_addr));
647
648 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
649
650 memset(zerolength, 0, sizeof(zerolength));
651
652 if (useIPv4)
653 range = 6;
654 else
655 range = 8;
656
657 /* find position of longest 0 run */
658 for (i = 0; i < range; i++) {
659 for (j = i; j < range; j++) {
660 if (in6.s6_addr16[j] != 0)
661 break;
662 zerolength[i]++;
663 }
664 }
665 for (i = 0; i < range; i++) {
666 if (zerolength[i] > longest) {
667 longest = zerolength[i];
668 colonpos = i;
669 }
670 }
671 if (longest == 1) /* don't compress a single 0 */
672 colonpos = -1;
673
674 /* emit address */
675 for (i = 0; i < range; i++) {
676 if (i == colonpos) {
677 if (needcolon || i == 0)
678 *p++ = ':';
679 *p++ = ':';
680 needcolon = false;
681 i += longest - 1;
682 continue;
683 }
684 if (needcolon) {
685 *p++ = ':';
686 needcolon = false;
687 }
688 /* hex u16 without leading 0s */
689 word = ntohs(in6.s6_addr16[i]);
690 hi = word >> 8;
691 lo = word & 0xff;
692 if (hi) {
693 if (hi > 0x0f)
694 p = hex_byte_pack(p, hi);
695 else
696 *p++ = hex_asc_lo(hi);
697 p = hex_byte_pack(p, lo);
698 }
699 else if (lo > 0x0f)
700 p = hex_byte_pack(p, lo);
701 else
702 *p++ = hex_asc_lo(lo);
703 needcolon = true;
704 }
705
706 if (useIPv4) {
707 if (needcolon)
708 *p++ = ':';
709 p = ip4_string(p, &in6.s6_addr[12], "I4");
710 }
711 *p = '\0';
712
713 return p;
714 }
715
716 static noinline_for_stack
717 char *ip6_string(char *p, const char *addr, const char *fmt)
718 {
719 int i;
720
721 for (i = 0; i < 8; i++) {
722 p = hex_byte_pack(p, *addr++);
723 p = hex_byte_pack(p, *addr++);
724 if (fmt[0] == 'I' && i != 7)
725 *p++ = ':';
726 }
727 *p = '\0';
728
729 return p;
730 }
731
732 static noinline_for_stack
733 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
734 struct printf_spec spec, const char *fmt)
735 {
736 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
737
738 if (fmt[0] == 'I' && fmt[2] == 'c')
739 ip6_compressed_string(ip6_addr, addr);
740 else
741 ip6_string(ip6_addr, addr, fmt);
742
743 return string(buf, end, ip6_addr, spec);
744 }
745
746 static noinline_for_stack
747 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
748 struct printf_spec spec, const char *fmt)
749 {
750 char ip4_addr[sizeof("255.255.255.255")];
751
752 ip4_string(ip4_addr, addr, fmt);
753
754 return string(buf, end, ip4_addr, spec);
755 }
756
757 static noinline_for_stack
758 char *uuid_string(char *buf, char *end, const u8 *addr,
759 struct printf_spec spec, const char *fmt)
760 {
761 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
762 char *p = uuid;
763 int i;
764 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
765 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
766 const u8 *index = be;
767 bool uc = false;
768
769 switch (*(++fmt)) {
770 case 'L':
771 uc = true; /* fall-through */
772 case 'l':
773 index = le;
774 break;
775 case 'B':
776 uc = true;
777 break;
778 }
779
780 for (i = 0; i < 16; i++) {
781 p = hex_byte_pack(p, addr[index[i]]);
782 switch (i) {
783 case 3:
784 case 5:
785 case 7:
786 case 9:
787 *p++ = '-';
788 break;
789 }
790 }
791
792 *p = 0;
793
794 if (uc) {
795 p = uuid;
796 do {
797 *p = toupper(*p);
798 } while (*(++p));
799 }
800
801 return string(buf, end, uuid, spec);
802 }
803
804 static
805 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
806 struct printf_spec spec)
807 {
808 spec.flags |= SPECIAL | SMALL | ZEROPAD;
809 if (spec.field_width == -1)
810 spec.field_width = 2 + 2 * sizeof(netdev_features_t);
811 spec.base = 16;
812
813 return number(buf, end, *(const netdev_features_t *)addr, spec);
814 }
815
816 int kptr_restrict __read_mostly;
817
818 /*
819 * Show a '%p' thing. A kernel extension is that the '%p' is followed
820 * by an extra set of alphanumeric characters that are extended format
821 * specifiers.
822 *
823 * Right now we handle:
824 *
825 * - 'F' For symbolic function descriptor pointers with offset
826 * - 'f' For simple symbolic function names without offset
827 * - 'S' For symbolic direct pointers with offset
828 * - 's' For symbolic direct pointers without offset
829 * - 'B' For backtraced symbolic direct pointers with offset
830 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
831 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
832 * - 'M' For a 6-byte MAC address, it prints the address in the
833 * usual colon-separated hex notation
834 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
835 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
836 * with a dash-separated hex notation
837 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
838 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
839 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
840 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
841 * IPv6 omits the colons (01020304...0f)
842 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
843 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
844 * - 'I6c' for IPv6 addresses printed as specified by
845 * http://tools.ietf.org/html/rfc5952
846 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
847 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
848 * Options for %pU are:
849 * b big endian lower case hex (default)
850 * B big endian UPPER case hex
851 * l little endian lower case hex
852 * L little endian UPPER case hex
853 * big endian output byte order is:
854 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
855 * little endian output byte order is:
856 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
857 * - 'V' For a struct va_format which contains a format string * and va_list *,
858 * call vsnprintf(->format, *->va_list).
859 * Implements a "recursive vsnprintf".
860 * Do not use this feature without some mechanism to verify the
861 * correctness of the format string and va_list arguments.
862 * - 'K' For a kernel pointer that should be hidden from unprivileged users
863 * - 'NF' For a netdev_features_t
864 *
865 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
866 * function pointers are really function descriptors, which contain a
867 * pointer to the real address.
868 */
869 static noinline_for_stack
870 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
871 struct printf_spec spec)
872 {
873 if (!ptr && *fmt != 'K') {
874 /*
875 * Print (null) with the same width as a pointer so it makes
876 * tabular output look nice.
877 */
878 if (spec.field_width == -1)
879 spec.field_width = 2 * sizeof(void *);
880 return string(buf, end, "(null)", spec);
881 }
882
883 switch (*fmt) {
884 case 'F':
885 case 'f':
886 ptr = dereference_function_descriptor(ptr);
887 /* Fallthrough */
888 case 'S':
889 case 's':
890 case 'B':
891 return symbol_string(buf, end, ptr, spec, *fmt);
892 case 'R':
893 case 'r':
894 return resource_string(buf, end, ptr, spec, fmt);
895 case 'M': /* Colon separated: 00:01:02:03:04:05 */
896 case 'm': /* Contiguous: 000102030405 */
897 /* [mM]F (FDDI, bit reversed) */
898 return mac_address_string(buf, end, ptr, spec, fmt);
899 case 'I': /* Formatted IP supported
900 * 4: 1.2.3.4
901 * 6: 0001:0203:...:0708
902 * 6c: 1::708 or 1::1.2.3.4
903 */
904 case 'i': /* Contiguous:
905 * 4: 001.002.003.004
906 * 6: 000102...0f
907 */
908 switch (fmt[1]) {
909 case '6':
910 return ip6_addr_string(buf, end, ptr, spec, fmt);
911 case '4':
912 return ip4_addr_string(buf, end, ptr, spec, fmt);
913 }
914 break;
915 case 'U':
916 return uuid_string(buf, end, ptr, spec, fmt);
917 case 'V':
918 {
919 va_list va;
920
921 va_copy(va, *((struct va_format *)ptr)->va);
922 buf += vsnprintf(buf, end > buf ? end - buf : 0,
923 ((struct va_format *)ptr)->fmt, va);
924 va_end(va);
925 return buf;
926 }
927 case 'K':
928 /*
929 * %pK cannot be used in IRQ context because its test
930 * for CAP_SYSLOG would be meaningless.
931 */
932 if (in_irq() || in_serving_softirq() || in_nmi()) {
933 if (spec.field_width == -1)
934 spec.field_width = 2 * sizeof(void *);
935 return string(buf, end, "pK-error", spec);
936 }
937 if (!((kptr_restrict == 0) ||
938 (kptr_restrict == 1 &&
939 has_capability_noaudit(current, CAP_SYSLOG))))
940 ptr = NULL;
941 break;
942 case 'N':
943 switch (fmt[1]) {
944 case 'F':
945 return netdev_feature_string(buf, end, ptr, spec);
946 }
947 break;
948 }
949 spec.flags |= SMALL;
950 if (spec.field_width == -1) {
951 spec.field_width = 2 * sizeof(void *);
952 spec.flags |= ZEROPAD;
953 }
954 spec.base = 16;
955
956 return number(buf, end, (unsigned long) ptr, spec);
957 }
958
959 /*
960 * Helper function to decode printf style format.
961 * Each call decode a token from the format and return the
962 * number of characters read (or likely the delta where it wants
963 * to go on the next call).
964 * The decoded token is returned through the parameters
965 *
966 * 'h', 'l', or 'L' for integer fields
967 * 'z' support added 23/7/1999 S.H.
968 * 'z' changed to 'Z' --davidm 1/25/99
969 * 't' added for ptrdiff_t
970 *
971 * @fmt: the format string
972 * @type of the token returned
973 * @flags: various flags such as +, -, # tokens..
974 * @field_width: overwritten width
975 * @base: base of the number (octal, hex, ...)
976 * @precision: precision of a number
977 * @qualifier: qualifier of a number (long, size_t, ...)
978 */
979 static noinline_for_stack
980 int format_decode(const char *fmt, struct printf_spec *spec)
981 {
982 const char *start = fmt;
983
984 /* we finished early by reading the field width */
985 if (spec->type == FORMAT_TYPE_WIDTH) {
986 if (spec->field_width < 0) {
987 spec->field_width = -spec->field_width;
988 spec->flags |= LEFT;
989 }
990 spec->type = FORMAT_TYPE_NONE;
991 goto precision;
992 }
993
994 /* we finished early by reading the precision */
995 if (spec->type == FORMAT_TYPE_PRECISION) {
996 if (spec->precision < 0)
997 spec->precision = 0;
998
999 spec->type = FORMAT_TYPE_NONE;
1000 goto qualifier;
1001 }
1002
1003 /* By default */
1004 spec->type = FORMAT_TYPE_NONE;
1005
1006 for (; *fmt ; ++fmt) {
1007 if (*fmt == '%')
1008 break;
1009 }
1010
1011 /* Return the current non-format string */
1012 if (fmt != start || !*fmt)
1013 return fmt - start;
1014
1015 /* Process flags */
1016 spec->flags = 0;
1017
1018 while (1) { /* this also skips first '%' */
1019 bool found = true;
1020
1021 ++fmt;
1022
1023 switch (*fmt) {
1024 case '-': spec->flags |= LEFT; break;
1025 case '+': spec->flags |= PLUS; break;
1026 case ' ': spec->flags |= SPACE; break;
1027 case '#': spec->flags |= SPECIAL; break;
1028 case '0': spec->flags |= ZEROPAD; break;
1029 default: found = false;
1030 }
1031
1032 if (!found)
1033 break;
1034 }
1035
1036 /* get field width */
1037 spec->field_width = -1;
1038
1039 if (isdigit(*fmt))
1040 spec->field_width = skip_atoi(&fmt);
1041 else if (*fmt == '*') {
1042 /* it's the next argument */
1043 spec->type = FORMAT_TYPE_WIDTH;
1044 return ++fmt - start;
1045 }
1046
1047 precision:
1048 /* get the precision */
1049 spec->precision = -1;
1050 if (*fmt == '.') {
1051 ++fmt;
1052 if (isdigit(*fmt)) {
1053 spec->precision = skip_atoi(&fmt);
1054 if (spec->precision < 0)
1055 spec->precision = 0;
1056 } else if (*fmt == '*') {
1057 /* it's the next argument */
1058 spec->type = FORMAT_TYPE_PRECISION;
1059 return ++fmt - start;
1060 }
1061 }
1062
1063 qualifier:
1064 /* get the conversion qualifier */
1065 spec->qualifier = -1;
1066 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1067 _tolower(*fmt) == 'z' || *fmt == 't') {
1068 spec->qualifier = *fmt++;
1069 if (unlikely(spec->qualifier == *fmt)) {
1070 if (spec->qualifier == 'l') {
1071 spec->qualifier = 'L';
1072 ++fmt;
1073 } else if (spec->qualifier == 'h') {
1074 spec->qualifier = 'H';
1075 ++fmt;
1076 }
1077 }
1078 }
1079
1080 /* default base */
1081 spec->base = 10;
1082 switch (*fmt) {
1083 case 'c':
1084 spec->type = FORMAT_TYPE_CHAR;
1085 return ++fmt - start;
1086
1087 case 's':
1088 spec->type = FORMAT_TYPE_STR;
1089 return ++fmt - start;
1090
1091 case 'p':
1092 spec->type = FORMAT_TYPE_PTR;
1093 return fmt - start;
1094 /* skip alnum */
1095
1096 case 'n':
1097 spec->type = FORMAT_TYPE_NRCHARS;
1098 return ++fmt - start;
1099
1100 case '%':
1101 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1102 return ++fmt - start;
1103
1104 /* integer number formats - set up the flags and "break" */
1105 case 'o':
1106 spec->base = 8;
1107 break;
1108
1109 case 'x':
1110 spec->flags |= SMALL;
1111
1112 case 'X':
1113 spec->base = 16;
1114 break;
1115
1116 case 'd':
1117 case 'i':
1118 spec->flags |= SIGN;
1119 case 'u':
1120 break;
1121
1122 default:
1123 spec->type = FORMAT_TYPE_INVALID;
1124 return fmt - start;
1125 }
1126
1127 if (spec->qualifier == 'L')
1128 spec->type = FORMAT_TYPE_LONG_LONG;
1129 else if (spec->qualifier == 'l') {
1130 if (spec->flags & SIGN)
1131 spec->type = FORMAT_TYPE_LONG;
1132 else
1133 spec->type = FORMAT_TYPE_ULONG;
1134 } else if (_tolower(spec->qualifier) == 'z') {
1135 spec->type = FORMAT_TYPE_SIZE_T;
1136 } else if (spec->qualifier == 't') {
1137 spec->type = FORMAT_TYPE_PTRDIFF;
1138 } else if (spec->qualifier == 'H') {
1139 if (spec->flags & SIGN)
1140 spec->type = FORMAT_TYPE_BYTE;
1141 else
1142 spec->type = FORMAT_TYPE_UBYTE;
1143 } else if (spec->qualifier == 'h') {
1144 if (spec->flags & SIGN)
1145 spec->type = FORMAT_TYPE_SHORT;
1146 else
1147 spec->type = FORMAT_TYPE_USHORT;
1148 } else {
1149 if (spec->flags & SIGN)
1150 spec->type = FORMAT_TYPE_INT;
1151 else
1152 spec->type = FORMAT_TYPE_UINT;
1153 }
1154
1155 return ++fmt - start;
1156 }
1157
1158 /**
1159 * vsnprintf - Format a string and place it in a buffer
1160 * @buf: The buffer to place the result into
1161 * @size: The size of the buffer, including the trailing null space
1162 * @fmt: The format string to use
1163 * @args: Arguments for the format string
1164 *
1165 * This function follows C99 vsnprintf, but has some extensions:
1166 * %pS output the name of a text symbol with offset
1167 * %ps output the name of a text symbol without offset
1168 * %pF output the name of a function pointer with its offset
1169 * %pf output the name of a function pointer without its offset
1170 * %pB output the name of a backtrace symbol with its offset
1171 * %pR output the address range in a struct resource with decoded flags
1172 * %pr output the address range in a struct resource with raw flags
1173 * %pM output a 6-byte MAC address with colons
1174 * %pm output a 6-byte MAC address without colons
1175 * %pI4 print an IPv4 address without leading zeros
1176 * %pi4 print an IPv4 address with leading zeros
1177 * %pI6 print an IPv6 address with colons
1178 * %pi6 print an IPv6 address without colons
1179 * %pI6c print an IPv6 address as specified by RFC 5952
1180 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1181 * case.
1182 * %n is ignored
1183 *
1184 * The return value is the number of characters which would
1185 * be generated for the given input, excluding the trailing
1186 * '\0', as per ISO C99. If you want to have the exact
1187 * number of characters written into @buf as return value
1188 * (not including the trailing '\0'), use vscnprintf(). If the
1189 * return is greater than or equal to @size, the resulting
1190 * string is truncated.
1191 *
1192 * If you're not already dealing with a va_list consider using snprintf().
1193 */
1194 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1195 {
1196 unsigned long long num;
1197 char *str, *end;
1198 struct printf_spec spec = {0};
1199
1200 /* Reject out-of-range values early. Large positive sizes are
1201 used for unknown buffer sizes. */
1202 if (WARN_ON_ONCE((int) size < 0))
1203 return 0;
1204
1205 str = buf;
1206 end = buf + size;
1207
1208 /* Make sure end is always >= buf */
1209 if (end < buf) {
1210 end = ((void *)-1);
1211 size = end - buf;
1212 }
1213
1214 while (*fmt) {
1215 const char *old_fmt = fmt;
1216 int read = format_decode(fmt, &spec);
1217
1218 fmt += read;
1219
1220 switch (spec.type) {
1221 case FORMAT_TYPE_NONE: {
1222 int copy = read;
1223 if (str < end) {
1224 if (copy > end - str)
1225 copy = end - str;
1226 memcpy(str, old_fmt, copy);
1227 }
1228 str += read;
1229 break;
1230 }
1231
1232 case FORMAT_TYPE_WIDTH:
1233 spec.field_width = va_arg(args, int);
1234 break;
1235
1236 case FORMAT_TYPE_PRECISION:
1237 spec.precision = va_arg(args, int);
1238 break;
1239
1240 case FORMAT_TYPE_CHAR: {
1241 char c;
1242
1243 if (!(spec.flags & LEFT)) {
1244 while (--spec.field_width > 0) {
1245 if (str < end)
1246 *str = ' ';
1247 ++str;
1248
1249 }
1250 }
1251 c = (unsigned char) va_arg(args, int);
1252 if (str < end)
1253 *str = c;
1254 ++str;
1255 while (--spec.field_width > 0) {
1256 if (str < end)
1257 *str = ' ';
1258 ++str;
1259 }
1260 break;
1261 }
1262
1263 case FORMAT_TYPE_STR:
1264 str = string(str, end, va_arg(args, char *), spec);
1265 break;
1266
1267 case FORMAT_TYPE_PTR:
1268 str = pointer(fmt+1, str, end, va_arg(args, void *),
1269 spec);
1270 while (isalnum(*fmt))
1271 fmt++;
1272 break;
1273
1274 case FORMAT_TYPE_PERCENT_CHAR:
1275 if (str < end)
1276 *str = '%';
1277 ++str;
1278 break;
1279
1280 case FORMAT_TYPE_INVALID:
1281 if (str < end)
1282 *str = '%';
1283 ++str;
1284 break;
1285
1286 case FORMAT_TYPE_NRCHARS: {
1287 u8 qualifier = spec.qualifier;
1288
1289 if (qualifier == 'l') {
1290 long *ip = va_arg(args, long *);
1291 *ip = (str - buf);
1292 } else if (_tolower(qualifier) == 'z') {
1293 size_t *ip = va_arg(args, size_t *);
1294 *ip = (str - buf);
1295 } else {
1296 int *ip = va_arg(args, int *);
1297 *ip = (str - buf);
1298 }
1299 break;
1300 }
1301
1302 default:
1303 switch (spec.type) {
1304 case FORMAT_TYPE_LONG_LONG:
1305 num = va_arg(args, long long);
1306 break;
1307 case FORMAT_TYPE_ULONG:
1308 num = va_arg(args, unsigned long);
1309 break;
1310 case FORMAT_TYPE_LONG:
1311 num = va_arg(args, long);
1312 break;
1313 case FORMAT_TYPE_SIZE_T:
1314 num = va_arg(args, size_t);
1315 break;
1316 case FORMAT_TYPE_PTRDIFF:
1317 num = va_arg(args, ptrdiff_t);
1318 break;
1319 case FORMAT_TYPE_UBYTE:
1320 num = (unsigned char) va_arg(args, int);
1321 break;
1322 case FORMAT_TYPE_BYTE:
1323 num = (signed char) va_arg(args, int);
1324 break;
1325 case FORMAT_TYPE_USHORT:
1326 num = (unsigned short) va_arg(args, int);
1327 break;
1328 case FORMAT_TYPE_SHORT:
1329 num = (short) va_arg(args, int);
1330 break;
1331 case FORMAT_TYPE_INT:
1332 num = (int) va_arg(args, int);
1333 break;
1334 default:
1335 num = va_arg(args, unsigned int);
1336 }
1337
1338 str = number(str, end, num, spec);
1339 }
1340 }
1341
1342 if (size > 0) {
1343 if (str < end)
1344 *str = '\0';
1345 else
1346 end[-1] = '\0';
1347 }
1348
1349 /* the trailing null byte doesn't count towards the total */
1350 return str-buf;
1351
1352 }
1353 EXPORT_SYMBOL(vsnprintf);
1354
1355 /**
1356 * vscnprintf - Format a string and place it in a buffer
1357 * @buf: The buffer to place the result into
1358 * @size: The size of the buffer, including the trailing null space
1359 * @fmt: The format string to use
1360 * @args: Arguments for the format string
1361 *
1362 * The return value is the number of characters which have been written into
1363 * the @buf not including the trailing '\0'. If @size is == 0 the function
1364 * returns 0.
1365 *
1366 * If you're not already dealing with a va_list consider using scnprintf().
1367 *
1368 * See the vsnprintf() documentation for format string extensions over C99.
1369 */
1370 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1371 {
1372 int i;
1373
1374 i = vsnprintf(buf, size, fmt, args);
1375
1376 if (likely(i < size))
1377 return i;
1378 if (size != 0)
1379 return size - 1;
1380 return 0;
1381 }
1382 EXPORT_SYMBOL(vscnprintf);
1383
1384 /**
1385 * snprintf - Format a string and place it in a buffer
1386 * @buf: The buffer to place the result into
1387 * @size: The size of the buffer, including the trailing null space
1388 * @fmt: The format string to use
1389 * @...: Arguments for the format string
1390 *
1391 * The return value is the number of characters which would be
1392 * generated for the given input, excluding the trailing null,
1393 * as per ISO C99. If the return is greater than or equal to
1394 * @size, the resulting string is truncated.
1395 *
1396 * See the vsnprintf() documentation for format string extensions over C99.
1397 */
1398 int snprintf(char *buf, size_t size, const char *fmt, ...)
1399 {
1400 va_list args;
1401 int i;
1402
1403 va_start(args, fmt);
1404 i = vsnprintf(buf, size, fmt, args);
1405 va_end(args);
1406
1407 return i;
1408 }
1409 EXPORT_SYMBOL(snprintf);
1410
1411 /**
1412 * scnprintf - Format a string and place it in a buffer
1413 * @buf: The buffer to place the result into
1414 * @size: The size of the buffer, including the trailing null space
1415 * @fmt: The format string to use
1416 * @...: Arguments for the format string
1417 *
1418 * The return value is the number of characters written into @buf not including
1419 * the trailing '\0'. If @size is == 0 the function returns 0.
1420 */
1421
1422 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1423 {
1424 va_list args;
1425 int i;
1426
1427 va_start(args, fmt);
1428 i = vscnprintf(buf, size, fmt, args);
1429 va_end(args);
1430
1431 return i;
1432 }
1433 EXPORT_SYMBOL(scnprintf);
1434
1435 /**
1436 * vsprintf - Format a string and place it in a buffer
1437 * @buf: The buffer to place the result into
1438 * @fmt: The format string to use
1439 * @args: Arguments for the format string
1440 *
1441 * The function returns the number of characters written
1442 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1443 * buffer overflows.
1444 *
1445 * If you're not already dealing with a va_list consider using sprintf().
1446 *
1447 * See the vsnprintf() documentation for format string extensions over C99.
1448 */
1449 int vsprintf(char *buf, const char *fmt, va_list args)
1450 {
1451 return vsnprintf(buf, INT_MAX, fmt, args);
1452 }
1453 EXPORT_SYMBOL(vsprintf);
1454
1455 /**
1456 * sprintf - Format a string and place it in a buffer
1457 * @buf: The buffer to place the result into
1458 * @fmt: The format string to use
1459 * @...: Arguments for the format string
1460 *
1461 * The function returns the number of characters written
1462 * into @buf. Use snprintf() or scnprintf() in order to avoid
1463 * buffer overflows.
1464 *
1465 * See the vsnprintf() documentation for format string extensions over C99.
1466 */
1467 int sprintf(char *buf, const char *fmt, ...)
1468 {
1469 va_list args;
1470 int i;
1471
1472 va_start(args, fmt);
1473 i = vsnprintf(buf, INT_MAX, fmt, args);
1474 va_end(args);
1475
1476 return i;
1477 }
1478 EXPORT_SYMBOL(sprintf);
1479
1480 #ifdef CONFIG_BINARY_PRINTF
1481 /*
1482 * bprintf service:
1483 * vbin_printf() - VA arguments to binary data
1484 * bstr_printf() - Binary data to text string
1485 */
1486
1487 /**
1488 * vbin_printf - Parse a format string and place args' binary value in a buffer
1489 * @bin_buf: The buffer to place args' binary value
1490 * @size: The size of the buffer(by words(32bits), not characters)
1491 * @fmt: The format string to use
1492 * @args: Arguments for the format string
1493 *
1494 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1495 * is skiped.
1496 *
1497 * The return value is the number of words(32bits) which would be generated for
1498 * the given input.
1499 *
1500 * NOTE:
1501 * If the return value is greater than @size, the resulting bin_buf is NOT
1502 * valid for bstr_printf().
1503 */
1504 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1505 {
1506 struct printf_spec spec = {0};
1507 char *str, *end;
1508
1509 str = (char *)bin_buf;
1510 end = (char *)(bin_buf + size);
1511
1512 #define save_arg(type) \
1513 do { \
1514 if (sizeof(type) == 8) { \
1515 unsigned long long value; \
1516 str = PTR_ALIGN(str, sizeof(u32)); \
1517 value = va_arg(args, unsigned long long); \
1518 if (str + sizeof(type) <= end) { \
1519 *(u32 *)str = *(u32 *)&value; \
1520 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1521 } \
1522 } else { \
1523 unsigned long value; \
1524 str = PTR_ALIGN(str, sizeof(type)); \
1525 value = va_arg(args, int); \
1526 if (str + sizeof(type) <= end) \
1527 *(typeof(type) *)str = (type)value; \
1528 } \
1529 str += sizeof(type); \
1530 } while (0)
1531
1532 while (*fmt) {
1533 int read = format_decode(fmt, &spec);
1534
1535 fmt += read;
1536
1537 switch (spec.type) {
1538 case FORMAT_TYPE_NONE:
1539 case FORMAT_TYPE_INVALID:
1540 case FORMAT_TYPE_PERCENT_CHAR:
1541 break;
1542
1543 case FORMAT_TYPE_WIDTH:
1544 case FORMAT_TYPE_PRECISION:
1545 save_arg(int);
1546 break;
1547
1548 case FORMAT_TYPE_CHAR:
1549 save_arg(char);
1550 break;
1551
1552 case FORMAT_TYPE_STR: {
1553 const char *save_str = va_arg(args, char *);
1554 size_t len;
1555
1556 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1557 || (unsigned long)save_str < PAGE_SIZE)
1558 save_str = "(null)";
1559 len = strlen(save_str) + 1;
1560 if (str + len < end)
1561 memcpy(str, save_str, len);
1562 str += len;
1563 break;
1564 }
1565
1566 case FORMAT_TYPE_PTR:
1567 save_arg(void *);
1568 /* skip all alphanumeric pointer suffixes */
1569 while (isalnum(*fmt))
1570 fmt++;
1571 break;
1572
1573 case FORMAT_TYPE_NRCHARS: {
1574 /* skip %n 's argument */
1575 u8 qualifier = spec.qualifier;
1576 void *skip_arg;
1577 if (qualifier == 'l')
1578 skip_arg = va_arg(args, long *);
1579 else if (_tolower(qualifier) == 'z')
1580 skip_arg = va_arg(args, size_t *);
1581 else
1582 skip_arg = va_arg(args, int *);
1583 break;
1584 }
1585
1586 default:
1587 switch (spec.type) {
1588
1589 case FORMAT_TYPE_LONG_LONG:
1590 save_arg(long long);
1591 break;
1592 case FORMAT_TYPE_ULONG:
1593 case FORMAT_TYPE_LONG:
1594 save_arg(unsigned long);
1595 break;
1596 case FORMAT_TYPE_SIZE_T:
1597 save_arg(size_t);
1598 break;
1599 case FORMAT_TYPE_PTRDIFF:
1600 save_arg(ptrdiff_t);
1601 break;
1602 case FORMAT_TYPE_UBYTE:
1603 case FORMAT_TYPE_BYTE:
1604 save_arg(char);
1605 break;
1606 case FORMAT_TYPE_USHORT:
1607 case FORMAT_TYPE_SHORT:
1608 save_arg(short);
1609 break;
1610 default:
1611 save_arg(int);
1612 }
1613 }
1614 }
1615
1616 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1617 #undef save_arg
1618 }
1619 EXPORT_SYMBOL_GPL(vbin_printf);
1620
1621 /**
1622 * bstr_printf - Format a string from binary arguments and place it in a buffer
1623 * @buf: The buffer to place the result into
1624 * @size: The size of the buffer, including the trailing null space
1625 * @fmt: The format string to use
1626 * @bin_buf: Binary arguments for the format string
1627 *
1628 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1629 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1630 * a binary buffer that generated by vbin_printf.
1631 *
1632 * The format follows C99 vsnprintf, but has some extensions:
1633 * see vsnprintf comment for details.
1634 *
1635 * The return value is the number of characters which would
1636 * be generated for the given input, excluding the trailing
1637 * '\0', as per ISO C99. If you want to have the exact
1638 * number of characters written into @buf as return value
1639 * (not including the trailing '\0'), use vscnprintf(). If the
1640 * return is greater than or equal to @size, the resulting
1641 * string is truncated.
1642 */
1643 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1644 {
1645 struct printf_spec spec = {0};
1646 char *str, *end;
1647 const char *args = (const char *)bin_buf;
1648
1649 if (WARN_ON_ONCE((int) size < 0))
1650 return 0;
1651
1652 str = buf;
1653 end = buf + size;
1654
1655 #define get_arg(type) \
1656 ({ \
1657 typeof(type) value; \
1658 if (sizeof(type) == 8) { \
1659 args = PTR_ALIGN(args, sizeof(u32)); \
1660 *(u32 *)&value = *(u32 *)args; \
1661 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1662 } else { \
1663 args = PTR_ALIGN(args, sizeof(type)); \
1664 value = *(typeof(type) *)args; \
1665 } \
1666 args += sizeof(type); \
1667 value; \
1668 })
1669
1670 /* Make sure end is always >= buf */
1671 if (end < buf) {
1672 end = ((void *)-1);
1673 size = end - buf;
1674 }
1675
1676 while (*fmt) {
1677 const char *old_fmt = fmt;
1678 int read = format_decode(fmt, &spec);
1679
1680 fmt += read;
1681
1682 switch (spec.type) {
1683 case FORMAT_TYPE_NONE: {
1684 int copy = read;
1685 if (str < end) {
1686 if (copy > end - str)
1687 copy = end - str;
1688 memcpy(str, old_fmt, copy);
1689 }
1690 str += read;
1691 break;
1692 }
1693
1694 case FORMAT_TYPE_WIDTH:
1695 spec.field_width = get_arg(int);
1696 break;
1697
1698 case FORMAT_TYPE_PRECISION:
1699 spec.precision = get_arg(int);
1700 break;
1701
1702 case FORMAT_TYPE_CHAR: {
1703 char c;
1704
1705 if (!(spec.flags & LEFT)) {
1706 while (--spec.field_width > 0) {
1707 if (str < end)
1708 *str = ' ';
1709 ++str;
1710 }
1711 }
1712 c = (unsigned char) get_arg(char);
1713 if (str < end)
1714 *str = c;
1715 ++str;
1716 while (--spec.field_width > 0) {
1717 if (str < end)
1718 *str = ' ';
1719 ++str;
1720 }
1721 break;
1722 }
1723
1724 case FORMAT_TYPE_STR: {
1725 const char *str_arg = args;
1726 args += strlen(str_arg) + 1;
1727 str = string(str, end, (char *)str_arg, spec);
1728 break;
1729 }
1730
1731 case FORMAT_TYPE_PTR:
1732 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1733 while (isalnum(*fmt))
1734 fmt++;
1735 break;
1736
1737 case FORMAT_TYPE_PERCENT_CHAR:
1738 case FORMAT_TYPE_INVALID:
1739 if (str < end)
1740 *str = '%';
1741 ++str;
1742 break;
1743
1744 case FORMAT_TYPE_NRCHARS:
1745 /* skip */
1746 break;
1747
1748 default: {
1749 unsigned long long num;
1750
1751 switch (spec.type) {
1752
1753 case FORMAT_TYPE_LONG_LONG:
1754 num = get_arg(long long);
1755 break;
1756 case FORMAT_TYPE_ULONG:
1757 case FORMAT_TYPE_LONG:
1758 num = get_arg(unsigned long);
1759 break;
1760 case FORMAT_TYPE_SIZE_T:
1761 num = get_arg(size_t);
1762 break;
1763 case FORMAT_TYPE_PTRDIFF:
1764 num = get_arg(ptrdiff_t);
1765 break;
1766 case FORMAT_TYPE_UBYTE:
1767 num = get_arg(unsigned char);
1768 break;
1769 case FORMAT_TYPE_BYTE:
1770 num = get_arg(signed char);
1771 break;
1772 case FORMAT_TYPE_USHORT:
1773 num = get_arg(unsigned short);
1774 break;
1775 case FORMAT_TYPE_SHORT:
1776 num = get_arg(short);
1777 break;
1778 case FORMAT_TYPE_UINT:
1779 num = get_arg(unsigned int);
1780 break;
1781 default:
1782 num = get_arg(int);
1783 }
1784
1785 str = number(str, end, num, spec);
1786 } /* default: */
1787 } /* switch(spec.type) */
1788 } /* while(*fmt) */
1789
1790 if (size > 0) {
1791 if (str < end)
1792 *str = '\0';
1793 else
1794 end[-1] = '\0';
1795 }
1796
1797 #undef get_arg
1798
1799 /* the trailing null byte doesn't count towards the total */
1800 return str - buf;
1801 }
1802 EXPORT_SYMBOL_GPL(bstr_printf);
1803
1804 /**
1805 * bprintf - Parse a format string and place args' binary value in a buffer
1806 * @bin_buf: The buffer to place args' binary value
1807 * @size: The size of the buffer(by words(32bits), not characters)
1808 * @fmt: The format string to use
1809 * @...: Arguments for the format string
1810 *
1811 * The function returns the number of words(u32) written
1812 * into @bin_buf.
1813 */
1814 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1815 {
1816 va_list args;
1817 int ret;
1818
1819 va_start(args, fmt);
1820 ret = vbin_printf(bin_buf, size, fmt, args);
1821 va_end(args);
1822
1823 return ret;
1824 }
1825 EXPORT_SYMBOL_GPL(bprintf);
1826
1827 #endif /* CONFIG_BINARY_PRINTF */
1828
1829 /**
1830 * vsscanf - Unformat a buffer into a list of arguments
1831 * @buf: input buffer
1832 * @fmt: format of buffer
1833 * @args: arguments
1834 */
1835 int vsscanf(const char *buf, const char *fmt, va_list args)
1836 {
1837 const char *str = buf;
1838 char *next;
1839 char digit;
1840 int num = 0;
1841 u8 qualifier;
1842 u8 base;
1843 s16 field_width;
1844 bool is_sign;
1845
1846 while (*fmt && *str) {
1847 /* skip any white space in format */
1848 /* white space in format matchs any amount of
1849 * white space, including none, in the input.
1850 */
1851 if (isspace(*fmt)) {
1852 fmt = skip_spaces(++fmt);
1853 str = skip_spaces(str);
1854 }
1855
1856 /* anything that is not a conversion must match exactly */
1857 if (*fmt != '%' && *fmt) {
1858 if (*fmt++ != *str++)
1859 break;
1860 continue;
1861 }
1862
1863 if (!*fmt)
1864 break;
1865 ++fmt;
1866
1867 /* skip this conversion.
1868 * advance both strings to next white space
1869 */
1870 if (*fmt == '*') {
1871 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1872 fmt++;
1873 while (!isspace(*str) && *str)
1874 str++;
1875 continue;
1876 }
1877
1878 /* get field width */
1879 field_width = -1;
1880 if (isdigit(*fmt))
1881 field_width = skip_atoi(&fmt);
1882
1883 /* get conversion qualifier */
1884 qualifier = -1;
1885 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1886 _tolower(*fmt) == 'z') {
1887 qualifier = *fmt++;
1888 if (unlikely(qualifier == *fmt)) {
1889 if (qualifier == 'h') {
1890 qualifier = 'H';
1891 fmt++;
1892 } else if (qualifier == 'l') {
1893 qualifier = 'L';
1894 fmt++;
1895 }
1896 }
1897 }
1898
1899 if (!*fmt || !*str)
1900 break;
1901
1902 base = 10;
1903 is_sign = 0;
1904
1905 switch (*fmt++) {
1906 case 'c':
1907 {
1908 char *s = (char *)va_arg(args, char*);
1909 if (field_width == -1)
1910 field_width = 1;
1911 do {
1912 *s++ = *str++;
1913 } while (--field_width > 0 && *str);
1914 num++;
1915 }
1916 continue;
1917 case 's':
1918 {
1919 char *s = (char *)va_arg(args, char *);
1920 if (field_width == -1)
1921 field_width = SHRT_MAX;
1922 /* first, skip leading white space in buffer */
1923 str = skip_spaces(str);
1924
1925 /* now copy until next white space */
1926 while (*str && !isspace(*str) && field_width--)
1927 *s++ = *str++;
1928 *s = '\0';
1929 num++;
1930 }
1931 continue;
1932 case 'n':
1933 /* return number of characters read so far */
1934 {
1935 int *i = (int *)va_arg(args, int*);
1936 *i = str - buf;
1937 }
1938 continue;
1939 case 'o':
1940 base = 8;
1941 break;
1942 case 'x':
1943 case 'X':
1944 base = 16;
1945 break;
1946 case 'i':
1947 base = 0;
1948 case 'd':
1949 is_sign = 1;
1950 case 'u':
1951 break;
1952 case '%':
1953 /* looking for '%' in str */
1954 if (*str++ != '%')
1955 return num;
1956 continue;
1957 default:
1958 /* invalid format; stop here */
1959 return num;
1960 }
1961
1962 /* have some sort of integer conversion.
1963 * first, skip white space in buffer.
1964 */
1965 str = skip_spaces(str);
1966
1967 digit = *str;
1968 if (is_sign && digit == '-')
1969 digit = *(str + 1);
1970
1971 if (!digit
1972 || (base == 16 && !isxdigit(digit))
1973 || (base == 10 && !isdigit(digit))
1974 || (base == 8 && (!isdigit(digit) || digit > '7'))
1975 || (base == 0 && !isdigit(digit)))
1976 break;
1977
1978 switch (qualifier) {
1979 case 'H': /* that's 'hh' in format */
1980 if (is_sign) {
1981 signed char *s = (signed char *)va_arg(args, signed char *);
1982 *s = (signed char)simple_strtol(str, &next, base);
1983 } else {
1984 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1985 *s = (unsigned char)simple_strtoul(str, &next, base);
1986 }
1987 break;
1988 case 'h':
1989 if (is_sign) {
1990 short *s = (short *)va_arg(args, short *);
1991 *s = (short)simple_strtol(str, &next, base);
1992 } else {
1993 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1994 *s = (unsigned short)simple_strtoul(str, &next, base);
1995 }
1996 break;
1997 case 'l':
1998 if (is_sign) {
1999 long *l = (long *)va_arg(args, long *);
2000 *l = simple_strtol(str, &next, base);
2001 } else {
2002 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2003 *l = simple_strtoul(str, &next, base);
2004 }
2005 break;
2006 case 'L':
2007 if (is_sign) {
2008 long long *l = (long long *)va_arg(args, long long *);
2009 *l = simple_strtoll(str, &next, base);
2010 } else {
2011 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2012 *l = simple_strtoull(str, &next, base);
2013 }
2014 break;
2015 case 'Z':
2016 case 'z':
2017 {
2018 size_t *s = (size_t *)va_arg(args, size_t *);
2019 *s = (size_t)simple_strtoul(str, &next, base);
2020 }
2021 break;
2022 default:
2023 if (is_sign) {
2024 int *i = (int *)va_arg(args, int *);
2025 *i = (int)simple_strtol(str, &next, base);
2026 } else {
2027 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2028 *i = (unsigned int)simple_strtoul(str, &next, base);
2029 }
2030 break;
2031 }
2032 num++;
2033
2034 if (!next)
2035 break;
2036 str = next;
2037 }
2038
2039 /*
2040 * Now we've come all the way through so either the input string or the
2041 * format ended. In the former case, there can be a %n at the current
2042 * position in the format that needs to be filled.
2043 */
2044 if (*fmt == '%' && *(fmt + 1) == 'n') {
2045 int *p = (int *)va_arg(args, int *);
2046 *p = str - buf;
2047 }
2048
2049 return num;
2050 }
2051 EXPORT_SYMBOL(vsscanf);
2052
2053 /**
2054 * sscanf - Unformat a buffer into a list of arguments
2055 * @buf: input buffer
2056 * @fmt: formatting of buffer
2057 * @...: resulting arguments
2058 */
2059 int sscanf(const char *buf, const char *fmt, ...)
2060 {
2061 va_list args;
2062 int i;
2063
2064 va_start(args, fmt);
2065 i = vsscanf(buf, fmt, args);
2066 va_end(args);
2067
2068 return i;
2069 }
2070 EXPORT_SYMBOL(sscanf);
Linux kernel - Deliverables
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