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pch_gbe: add extra clean tx
[linux-2.6.git] / lib / vsprintf.c
blobc3f36d415bdf43034415c801b8e3f922f5e5b928
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 ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
116 * (with permission from the author, Douglas W. Jones).
117 */
118
119 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
120 /* Formats correctly any integer in [0, 999999999] */
121 static noinline_for_stack
122 char *put_dec_full9(char *buf, unsigned q)
123 {
124 unsigned r;
125
126 /*
127 * Possible ways to approx. divide by 10
128 * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit)
129 * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul)
130 * (x * 0x6667) >> 18 x < 43699
131 * (x * 0x3334) >> 17 x < 16389
132 * (x * 0x199a) >> 16 x < 16389
133 * (x * 0x0ccd) >> 15 x < 16389
134 * (x * 0x0667) >> 14 x < 2739
135 * (x * 0x0334) >> 13 x < 1029
136 * (x * 0x019a) >> 12 x < 1029
137 * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386)
138 * (x * 0x0067) >> 10 x < 179
139 * (x * 0x0034) >> 9 x < 69 same
140 * (x * 0x001a) >> 8 x < 69 same
141 * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386)
142 * (x * 0x0007) >> 6 x < 19
143 * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html>
144 */
145 r = (q * (uint64_t)0x1999999a) >> 32;
146 *buf++ = (q - 10 * r) + '0'; /* 1 */
147 q = (r * (uint64_t)0x1999999a) >> 32;
148 *buf++ = (r - 10 * q) + '0'; /* 2 */
149 r = (q * (uint64_t)0x1999999a) >> 32;
150 *buf++ = (q - 10 * r) + '0'; /* 3 */
151 q = (r * (uint64_t)0x1999999a) >> 32;
152 *buf++ = (r - 10 * q) + '0'; /* 4 */
153 r = (q * (uint64_t)0x1999999a) >> 32;
154 *buf++ = (q - 10 * r) + '0'; /* 5 */
155 /* Now value is under 10000, can avoid 64-bit multiply */
156 q = (r * 0x199a) >> 16;
157 *buf++ = (r - 10 * q) + '0'; /* 6 */
158 r = (q * 0xcd) >> 11;
159 *buf++ = (q - 10 * r) + '0'; /* 7 */
160 q = (r * 0xcd) >> 11;
161 *buf++ = (r - 10 * q) + '0'; /* 8 */
162 *buf++ = q + '0'; /* 9 */
163 return buf;
164 }
165 #endif
166
167 /* Similar to above but do not pad with zeros.
168 * Code can be easily arranged to print 9 digits too, but our callers
169 * always call put_dec_full9() instead when the number has 9 decimal digits.
170 */
171 static noinline_for_stack
172 char *put_dec_trunc8(char *buf, unsigned r)
173 {
174 unsigned q;
175
176 /* Copy of previous function's body with added early returns */
177 q = (r * (uint64_t)0x1999999a) >> 32;
178 *buf++ = (r - 10 * q) + '0'; /* 2 */
179 if (q == 0)
180 return buf;
181 r = (q * (uint64_t)0x1999999a) >> 32;
182 *buf++ = (q - 10 * r) + '0'; /* 3 */
183 if (r == 0)
184 return buf;
185 q = (r * (uint64_t)0x1999999a) >> 32;
186 *buf++ = (r - 10 * q) + '0'; /* 4 */
187 if (q == 0)
188 return buf;
189 r = (q * (uint64_t)0x1999999a) >> 32;
190 *buf++ = (q - 10 * r) + '0'; /* 5 */
191 if (r == 0)
192 return buf;
193 q = (r * 0x199a) >> 16;
194 *buf++ = (r - 10 * q) + '0'; /* 6 */
195 if (q == 0)
196 return buf;
197 r = (q * 0xcd) >> 11;
198 *buf++ = (q - 10 * r) + '0'; /* 7 */
199 if (r == 0)
200 return buf;
201 q = (r * 0xcd) >> 11;
202 *buf++ = (r - 10 * q) + '0'; /* 8 */
203 if (q == 0)
204 return buf;
205 *buf++ = q + '0'; /* 9 */
206 return buf;
207 }
208
209 /* There are two algorithms to print larger numbers.
210 * One is generic: divide by 1000000000 and repeatedly print
211 * groups of (up to) 9 digits. It's conceptually simple,
212 * but requires a (unsigned long long) / 1000000000 division.
213 *
214 * Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
215 * manipulates them cleverly and generates groups of 4 decimal digits.
216 * It so happens that it does NOT require long long division.
217 *
218 * If long is > 32 bits, division of 64-bit values is relatively easy,
219 * and we will use the first algorithm.
220 * If long long is > 64 bits (strange architecture with VERY large long long),
221 * second algorithm can't be used, and we again use the first one.
222 *
223 * Else (if long is 32 bits and long long is 64 bits) we use second one.
224 */
225
226 #if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64
227
228 /* First algorithm: generic */
229
230 static
231 char *put_dec(char *buf, unsigned long long n)
232 {
233 if (n >= 100*1000*1000) {
234 while (n >= 1000*1000*1000)
235 buf = put_dec_full9(buf, do_div(n, 1000*1000*1000));
236 if (n >= 100*1000*1000)
237 return put_dec_full9(buf, n);
238 }
239 return put_dec_trunc8(buf, n);
240 }
241
242 #else
243
244 /* Second algorithm: valid only for 64-bit long longs */
245
246 static noinline_for_stack
247 char *put_dec_full4(char *buf, unsigned q)
248 {
249 unsigned r;
250 r = (q * 0xcccd) >> 19;
251 *buf++ = (q - 10 * r) + '0';
252 q = (r * 0x199a) >> 16;
253 *buf++ = (r - 10 * q) + '0';
254 r = (q * 0xcd) >> 11;
255 *buf++ = (q - 10 * r) + '0';
256 *buf++ = r + '0';
257 return buf;
258 }
259
260 /* Based on code by Douglas W. Jones found at
261 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
262 * (with permission from the author).
263 * Performs no 64-bit division and hence should be fast on 32-bit machines.
264 */
265 static
266 char *put_dec(char *buf, unsigned long long n)
267 {
268 uint32_t d3, d2, d1, q, h;
269
270 if (n < 100*1000*1000)
271 return put_dec_trunc8(buf, n);
272
273 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
274 h = (n >> 32);
275 d2 = (h ) & 0xffff;
276 d3 = (h >> 16); /* implicit "& 0xffff" */
277
278 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
279
280 buf = put_dec_full4(buf, q % 10000);
281 q = q / 10000;
282
283 d1 = q + 7671 * d3 + 9496 * d2 + 6 * d1;
284 buf = put_dec_full4(buf, d1 % 10000);
285 q = d1 / 10000;
286
287 d2 = q + 4749 * d3 + 42 * d2;
288 buf = put_dec_full4(buf, d2 % 10000);
289 q = d2 / 10000;
290
291 d3 = q + 281 * d3;
292 if (!d3)
293 goto done;
294 buf = put_dec_full4(buf, d3 % 10000);
295 q = d3 / 10000;
296 if (!q)
297 goto done;
298 buf = put_dec_full4(buf, q);
299 done:
300 while (buf[-1] == '0')
301 --buf;
302
303 return buf;
304 }
305
306 #endif
307
308 /*
309 * Convert passed number to decimal string.
310 * Returns the length of string. On buffer overflow, returns 0.
311 *
312 * If speed is not important, use snprintf(). It's easy to read the code.
313 */
314 int num_to_str(char *buf, int size, unsigned long long num)
315 {
316 char tmp[sizeof(num) * 3];
317 int idx, len;
318
319 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
320 if (num <= 9) {
321 tmp[0] = '0' + num;
322 len = 1;
323 } else {
324 len = put_dec(tmp, num) - tmp;
325 }
326
327 if (len > size)
328 return 0;
329 for (idx = 0; idx < len; ++idx)
330 buf[idx] = tmp[len - idx - 1];
331 return len;
332 }
333
334 #define ZEROPAD 1 /* pad with zero */
335 #define SIGN 2 /* unsigned/signed long */
336 #define PLUS 4 /* show plus */
337 #define SPACE 8 /* space if plus */
338 #define LEFT 16 /* left justified */
339 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
340 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
341
342 enum format_type {
343 FORMAT_TYPE_NONE, /* Just a string part */
344 FORMAT_TYPE_WIDTH,
345 FORMAT_TYPE_PRECISION,
346 FORMAT_TYPE_CHAR,
347 FORMAT_TYPE_STR,
348 FORMAT_TYPE_PTR,
349 FORMAT_TYPE_PERCENT_CHAR,
350 FORMAT_TYPE_INVALID,
351 FORMAT_TYPE_LONG_LONG,
352 FORMAT_TYPE_ULONG,
353 FORMAT_TYPE_LONG,
354 FORMAT_TYPE_UBYTE,
355 FORMAT_TYPE_BYTE,
356 FORMAT_TYPE_USHORT,
357 FORMAT_TYPE_SHORT,
358 FORMAT_TYPE_UINT,
359 FORMAT_TYPE_INT,
360 FORMAT_TYPE_NRCHARS,
361 FORMAT_TYPE_SIZE_T,
362 FORMAT_TYPE_PTRDIFF
363 };
364
365 struct printf_spec {
366 u8 type; /* format_type enum */
367 u8 flags; /* flags to number() */
368 u8 base; /* number base, 8, 10 or 16 only */
369 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
370 s16 field_width; /* width of output field */
371 s16 precision; /* # of digits/chars */
372 };
373
374 static noinline_for_stack
375 char *number(char *buf, char *end, unsigned long long num,
376 struct printf_spec spec)
377 {
378 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
379 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
380
381 char tmp[66];
382 char sign;
383 char locase;
384 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
385 int i;
386 bool is_zero = num == 0LL;
387
388 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
389 * produces same digits or (maybe lowercased) letters */
390 locase = (spec.flags & SMALL);
391 if (spec.flags & LEFT)
392 spec.flags &= ~ZEROPAD;
393 sign = 0;
394 if (spec.flags & SIGN) {
395 if ((signed long long)num < 0) {
396 sign = '-';
397 num = -(signed long long)num;
398 spec.field_width--;
399 } else if (spec.flags & PLUS) {
400 sign = '+';
401 spec.field_width--;
402 } else if (spec.flags & SPACE) {
403 sign = ' ';
404 spec.field_width--;
405 }
406 }
407 if (need_pfx) {
408 if (spec.base == 16)
409 spec.field_width -= 2;
410 else if (!is_zero)
411 spec.field_width--;
412 }
413
414 /* generate full string in tmp[], in reverse order */
415 i = 0;
416 if (num < spec.base)
417 tmp[i++] = digits[num] | locase;
418 /* Generic code, for any base:
419 else do {
420 tmp[i++] = (digits[do_div(num,base)] | locase);
421 } while (num != 0);
422 */
423 else if (spec.base != 10) { /* 8 or 16 */
424 int mask = spec.base - 1;
425 int shift = 3;
426
427 if (spec.base == 16)
428 shift = 4;
429 do {
430 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
431 num >>= shift;
432 } while (num);
433 } else { /* base 10 */
434 i = put_dec(tmp, num) - tmp;
435 }
436
437 /* printing 100 using %2d gives "100", not "00" */
438 if (i > spec.precision)
439 spec.precision = i;
440 /* leading space padding */
441 spec.field_width -= spec.precision;
442 if (!(spec.flags & (ZEROPAD+LEFT))) {
443 while (--spec.field_width >= 0) {
444 if (buf < end)
445 *buf = ' ';
446 ++buf;
447 }
448 }
449 /* sign */
450 if (sign) {
451 if (buf < end)
452 *buf = sign;
453 ++buf;
454 }
455 /* "0x" / "0" prefix */
456 if (need_pfx) {
457 if (spec.base == 16 || !is_zero) {
458 if (buf < end)
459 *buf = '0';
460 ++buf;
461 }
462 if (spec.base == 16) {
463 if (buf < end)
464 *buf = ('X' | locase);
465 ++buf;
466 }
467 }
468 /* zero or space padding */
469 if (!(spec.flags & LEFT)) {
470 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
471 while (--spec.field_width >= 0) {
472 if (buf < end)
473 *buf = c;
474 ++buf;
475 }
476 }
477 /* hmm even more zero padding? */
478 while (i <= --spec.precision) {
479 if (buf < end)
480 *buf = '0';
481 ++buf;
482 }
483 /* actual digits of result */
484 while (--i >= 0) {
485 if (buf < end)
486 *buf = tmp[i];
487 ++buf;
488 }
489 /* trailing space padding */
490 while (--spec.field_width >= 0) {
491 if (buf < end)
492 *buf = ' ';
493 ++buf;
494 }
495
496 return buf;
497 }
498
499 static noinline_for_stack
500 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
501 {
502 int len, i;
503
504 if ((unsigned long)s < PAGE_SIZE)
505 s = "(null)";
506
507 len = strnlen(s, spec.precision);
508
509 if (!(spec.flags & LEFT)) {
510 while (len < spec.field_width--) {
511 if (buf < end)
512 *buf = ' ';
513 ++buf;
514 }
515 }
516 for (i = 0; i < len; ++i) {
517 if (buf < end)
518 *buf = *s;
519 ++buf; ++s;
520 }
521 while (len < spec.field_width--) {
522 if (buf < end)
523 *buf = ' ';
524 ++buf;
525 }
526
527 return buf;
528 }
529
530 static noinline_for_stack
531 char *symbol_string(char *buf, char *end, void *ptr,
532 struct printf_spec spec, char ext)
533 {
534 unsigned long value = (unsigned long) ptr;
535 #ifdef CONFIG_KALLSYMS
536 char sym[KSYM_SYMBOL_LEN];
537 if (ext == 'B')
538 sprint_backtrace(sym, value);
539 else if (ext != 'f' && ext != 's')
540 sprint_symbol(sym, value);
541 else
542 sprint_symbol_no_offset(sym, value);
543
544 return string(buf, end, sym, spec);
545 #else
546 spec.field_width = 2 * sizeof(void *);
547 spec.flags |= SPECIAL | SMALL | ZEROPAD;
548 spec.base = 16;
549
550 return number(buf, end, value, spec);
551 #endif
552 }
553
554 static noinline_for_stack
555 char *resource_string(char *buf, char *end, struct resource *res,
556 struct printf_spec spec, const char *fmt)
557 {
558 #ifndef IO_RSRC_PRINTK_SIZE
559 #define IO_RSRC_PRINTK_SIZE 6
560 #endif
561
562 #ifndef MEM_RSRC_PRINTK_SIZE
563 #define MEM_RSRC_PRINTK_SIZE 10
564 #endif
565 static const struct printf_spec io_spec = {
566 .base = 16,
567 .field_width = IO_RSRC_PRINTK_SIZE,
568 .precision = -1,
569 .flags = SPECIAL | SMALL | ZEROPAD,
570 };
571 static const struct printf_spec mem_spec = {
572 .base = 16,
573 .field_width = MEM_RSRC_PRINTK_SIZE,
574 .precision = -1,
575 .flags = SPECIAL | SMALL | ZEROPAD,
576 };
577 static const struct printf_spec bus_spec = {
578 .base = 16,
579 .field_width = 2,
580 .precision = -1,
581 .flags = SMALL | ZEROPAD,
582 };
583 static const struct printf_spec dec_spec = {
584 .base = 10,
585 .precision = -1,
586 .flags = 0,
587 };
588 static const struct printf_spec str_spec = {
589 .field_width = -1,
590 .precision = 10,
591 .flags = LEFT,
592 };
593 static const struct printf_spec flag_spec = {
594 .base = 16,
595 .precision = -1,
596 .flags = SPECIAL | SMALL,
597 };
598
599 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
600 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
601 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
602 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
603 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
604 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
605 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
606 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
607
608 char *p = sym, *pend = sym + sizeof(sym);
609 int decode = (fmt[0] == 'R') ? 1 : 0;
610 const struct printf_spec *specp;
611
612 *p++ = '[';
613 if (res->flags & IORESOURCE_IO) {
614 p = string(p, pend, "io ", str_spec);
615 specp = &io_spec;
616 } else if (res->flags & IORESOURCE_MEM) {
617 p = string(p, pend, "mem ", str_spec);
618 specp = &mem_spec;
619 } else if (res->flags & IORESOURCE_IRQ) {
620 p = string(p, pend, "irq ", str_spec);
621 specp = &dec_spec;
622 } else if (res->flags & IORESOURCE_DMA) {
623 p = string(p, pend, "dma ", str_spec);
624 specp = &dec_spec;
625 } else if (res->flags & IORESOURCE_BUS) {
626 p = string(p, pend, "bus ", str_spec);
627 specp = &bus_spec;
628 } else {
629 p = string(p, pend, "??? ", str_spec);
630 specp = &mem_spec;
631 decode = 0;
632 }
633 p = number(p, pend, res->start, *specp);
634 if (res->start != res->end) {
635 *p++ = '-';
636 p = number(p, pend, res->end, *specp);
637 }
638 if (decode) {
639 if (res->flags & IORESOURCE_MEM_64)
640 p = string(p, pend, " 64bit", str_spec);
641 if (res->flags & IORESOURCE_PREFETCH)
642 p = string(p, pend, " pref", str_spec);
643 if (res->flags & IORESOURCE_WINDOW)
644 p = string(p, pend, " window", str_spec);
645 if (res->flags & IORESOURCE_DISABLED)
646 p = string(p, pend, " disabled", str_spec);
647 } else {
648 p = string(p, pend, " flags ", str_spec);
649 p = number(p, pend, res->flags, flag_spec);
650 }
651 *p++ = ']';
652 *p = '\0';
653
654 return string(buf, end, sym, spec);
655 }
656
657 static noinline_for_stack
658 char *mac_address_string(char *buf, char *end, u8 *addr,
659 struct printf_spec spec, const char *fmt)
660 {
661 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
662 char *p = mac_addr;
663 int i;
664 char separator;
665
666 if (fmt[1] == 'F') { /* FDDI canonical format */
667 separator = '-';
668 } else {
669 separator = ':';
670 }
671
672 for (i = 0; i < 6; i++) {
673 p = hex_byte_pack(p, addr[i]);
674 if (fmt[0] == 'M' && i != 5)
675 *p++ = separator;
676 }
677 *p = '\0';
678
679 return string(buf, end, mac_addr, spec);
680 }
681
682 static noinline_for_stack
683 char *ip4_string(char *p, const u8 *addr, const char *fmt)
684 {
685 int i;
686 bool leading_zeros = (fmt[0] == 'i');
687 int index;
688 int step;
689
690 switch (fmt[2]) {
691 case 'h':
692 #ifdef __BIG_ENDIAN
693 index = 0;
694 step = 1;
695 #else
696 index = 3;
697 step = -1;
698 #endif
699 break;
700 case 'l':
701 index = 3;
702 step = -1;
703 break;
704 case 'n':
705 case 'b':
706 default:
707 index = 0;
708 step = 1;
709 break;
710 }
711 for (i = 0; i < 4; i++) {
712 char temp[3]; /* hold each IP quad in reverse order */
713 int digits = put_dec_trunc8(temp, addr[index]) - temp;
714 if (leading_zeros) {
715 if (digits < 3)
716 *p++ = '0';
717 if (digits < 2)
718 *p++ = '0';
719 }
720 /* reverse the digits in the quad */
721 while (digits--)
722 *p++ = temp[digits];
723 if (i < 3)
724 *p++ = '.';
725 index += step;
726 }
727 *p = '\0';
728
729 return p;
730 }
731
732 static noinline_for_stack
733 char *ip6_compressed_string(char *p, const char *addr)
734 {
735 int i, j, range;
736 unsigned char zerolength[8];
737 int longest = 1;
738 int colonpos = -1;
739 u16 word;
740 u8 hi, lo;
741 bool needcolon = false;
742 bool useIPv4;
743 struct in6_addr in6;
744
745 memcpy(&in6, addr, sizeof(struct in6_addr));
746
747 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
748
749 memset(zerolength, 0, sizeof(zerolength));
750
751 if (useIPv4)
752 range = 6;
753 else
754 range = 8;
755
756 /* find position of longest 0 run */
757 for (i = 0; i < range; i++) {
758 for (j = i; j < range; j++) {
759 if (in6.s6_addr16[j] != 0)
760 break;
761 zerolength[i]++;
762 }
763 }
764 for (i = 0; i < range; i++) {
765 if (zerolength[i] > longest) {
766 longest = zerolength[i];
767 colonpos = i;
768 }
769 }
770 if (longest == 1) /* don't compress a single 0 */
771 colonpos = -1;
772
773 /* emit address */
774 for (i = 0; i < range; i++) {
775 if (i == colonpos) {
776 if (needcolon || i == 0)
777 *p++ = ':';
778 *p++ = ':';
779 needcolon = false;
780 i += longest - 1;
781 continue;
782 }
783 if (needcolon) {
784 *p++ = ':';
785 needcolon = false;
786 }
787 /* hex u16 without leading 0s */
788 word = ntohs(in6.s6_addr16[i]);
789 hi = word >> 8;
790 lo = word & 0xff;
791 if (hi) {
792 if (hi > 0x0f)
793 p = hex_byte_pack(p, hi);
794 else
795 *p++ = hex_asc_lo(hi);
796 p = hex_byte_pack(p, lo);
797 }
798 else if (lo > 0x0f)
799 p = hex_byte_pack(p, lo);
800 else
801 *p++ = hex_asc_lo(lo);
802 needcolon = true;
803 }
804
805 if (useIPv4) {
806 if (needcolon)
807 *p++ = ':';
808 p = ip4_string(p, &in6.s6_addr[12], "I4");
809 }
810 *p = '\0';
811
812 return p;
813 }
814
815 static noinline_for_stack
816 char *ip6_string(char *p, const char *addr, const char *fmt)
817 {
818 int i;
819
820 for (i = 0; i < 8; i++) {
821 p = hex_byte_pack(p, *addr++);
822 p = hex_byte_pack(p, *addr++);
823 if (fmt[0] == 'I' && i != 7)
824 *p++ = ':';
825 }
826 *p = '\0';
827
828 return p;
829 }
830
831 static noinline_for_stack
832 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
833 struct printf_spec spec, const char *fmt)
834 {
835 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
836
837 if (fmt[0] == 'I' && fmt[2] == 'c')
838 ip6_compressed_string(ip6_addr, addr);
839 else
840 ip6_string(ip6_addr, addr, fmt);
841
842 return string(buf, end, ip6_addr, spec);
843 }
844
845 static noinline_for_stack
846 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
847 struct printf_spec spec, const char *fmt)
848 {
849 char ip4_addr[sizeof("255.255.255.255")];
850
851 ip4_string(ip4_addr, addr, fmt);
852
853 return string(buf, end, ip4_addr, spec);
854 }
855
856 static noinline_for_stack
857 char *uuid_string(char *buf, char *end, const u8 *addr,
858 struct printf_spec spec, const char *fmt)
859 {
860 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
861 char *p = uuid;
862 int i;
863 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
864 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
865 const u8 *index = be;
866 bool uc = false;
867
868 switch (*(++fmt)) {
869 case 'L':
870 uc = true; /* fall-through */
871 case 'l':
872 index = le;
873 break;
874 case 'B':
875 uc = true;
876 break;
877 }
878
879 for (i = 0; i < 16; i++) {
880 p = hex_byte_pack(p, addr[index[i]]);
881 switch (i) {
882 case 3:
883 case 5:
884 case 7:
885 case 9:
886 *p++ = '-';
887 break;
888 }
889 }
890
891 *p = 0;
892
893 if (uc) {
894 p = uuid;
895 do {
896 *p = toupper(*p);
897 } while (*(++p));
898 }
899
900 return string(buf, end, uuid, spec);
901 }
902
903 static
904 char *netdev_feature_string(char *buf, char *end, const u8 *addr,
905 struct printf_spec spec)
906 {
907 spec.flags |= SPECIAL | SMALL | ZEROPAD;
908 if (spec.field_width == -1)
909 spec.field_width = 2 + 2 * sizeof(netdev_features_t);
910 spec.base = 16;
911
912 return number(buf, end, *(const netdev_features_t *)addr, spec);
913 }
914
915 int kptr_restrict __read_mostly;
916
917 /*
918 * Show a '%p' thing. A kernel extension is that the '%p' is followed
919 * by an extra set of alphanumeric characters that are extended format
920 * specifiers.
921 *
922 * Right now we handle:
923 *
924 * - 'F' For symbolic function descriptor pointers with offset
925 * - 'f' For simple symbolic function names without offset
926 * - 'S' For symbolic direct pointers with offset
927 * - 's' For symbolic direct pointers without offset
928 * - 'B' For backtraced symbolic direct pointers with offset
929 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
930 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
931 * - 'M' For a 6-byte MAC address, it prints the address in the
932 * usual colon-separated hex notation
933 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
934 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
935 * with a dash-separated hex notation
936 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
937 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
938 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
939 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
940 * IPv6 omits the colons (01020304...0f)
941 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
942 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
943 * - 'I6c' for IPv6 addresses printed as specified by
944 * http://tools.ietf.org/html/rfc5952
945 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
946 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
947 * Options for %pU are:
948 * b big endian lower case hex (default)
949 * B big endian UPPER case hex
950 * l little endian lower case hex
951 * L little endian UPPER case hex
952 * big endian output byte order is:
953 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
954 * little endian output byte order is:
955 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
956 * - 'V' For a struct va_format which contains a format string * and va_list *,
957 * call vsnprintf(->format, *->va_list).
958 * Implements a "recursive vsnprintf".
959 * Do not use this feature without some mechanism to verify the
960 * correctness of the format string and va_list arguments.
961 * - 'K' For a kernel pointer that should be hidden from unprivileged users
962 * - 'NF' For a netdev_features_t
963 *
964 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
965 * function pointers are really function descriptors, which contain a
966 * pointer to the real address.
967 */
968 static noinline_for_stack
969 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
970 struct printf_spec spec)
971 {
972 int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
973
974 if (!ptr && *fmt != 'K') {
975 /*
976 * Print (null) with the same width as a pointer so it makes
977 * tabular output look nice.
978 */
979 if (spec.field_width == -1)
980 spec.field_width = default_width;
981 return string(buf, end, "(null)", spec);
982 }
983
984 switch (*fmt) {
985 case 'F':
986 case 'f':
987 ptr = dereference_function_descriptor(ptr);
988 /* Fallthrough */
989 case 'S':
990 case 's':
991 case 'B':
992 return symbol_string(buf, end, ptr, spec, *fmt);
993 case 'R':
994 case 'r':
995 return resource_string(buf, end, ptr, spec, fmt);
996 case 'M': /* Colon separated: 00:01:02:03:04:05 */
997 case 'm': /* Contiguous: 000102030405 */
998 /* [mM]F (FDDI, bit reversed) */
999 return mac_address_string(buf, end, ptr, spec, fmt);
1000 case 'I': /* Formatted IP supported
1001 * 4: 1.2.3.4
1002 * 6: 0001:0203:...:0708
1003 * 6c: 1::708 or 1::1.2.3.4
1004 */
1005 case 'i': /* Contiguous:
1006 * 4: 001.002.003.004
1007 * 6: 000102...0f
1008 */
1009 switch (fmt[1]) {
1010 case '6':
1011 return ip6_addr_string(buf, end, ptr, spec, fmt);
1012 case '4':
1013 return ip4_addr_string(buf, end, ptr, spec, fmt);
1014 }
1015 break;
1016 case 'U':
1017 return uuid_string(buf, end, ptr, spec, fmt);
1018 case 'V':
1019 {
1020 va_list va;
1021
1022 va_copy(va, *((struct va_format *)ptr)->va);
1023 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1024 ((struct va_format *)ptr)->fmt, va);
1025 va_end(va);
1026 return buf;
1027 }
1028 case 'K':
1029 /*
1030 * %pK cannot be used in IRQ context because its test
1031 * for CAP_SYSLOG would be meaningless.
1032 */
1033 if (in_irq() || in_serving_softirq() || in_nmi()) {
1034 if (spec.field_width == -1)
1035 spec.field_width = default_width;
1036 return string(buf, end, "pK-error", spec);
1037 }
1038 if (!((kptr_restrict == 0) ||
1039 (kptr_restrict == 1 &&
1040 has_capability_noaudit(current, CAP_SYSLOG))))
1041 ptr = NULL;
1042 break;
1043 case 'N':
1044 switch (fmt[1]) {
1045 case 'F':
1046 return netdev_feature_string(buf, end, ptr, spec);
1047 }
1048 break;
1049 }
1050 spec.flags |= SMALL;
1051 if (spec.field_width == -1) {
1052 spec.field_width = default_width;
1053 spec.flags |= ZEROPAD;
1054 }
1055 spec.base = 16;
1056
1057 return number(buf, end, (unsigned long) ptr, spec);
1058 }
1059
1060 /*
1061 * Helper function to decode printf style format.
1062 * Each call decode a token from the format and return the
1063 * number of characters read (or likely the delta where it wants
1064 * to go on the next call).
1065 * The decoded token is returned through the parameters
1066 *
1067 * 'h', 'l', or 'L' for integer fields
1068 * 'z' support added 23/7/1999 S.H.
1069 * 'z' changed to 'Z' --davidm 1/25/99
1070 * 't' added for ptrdiff_t
1071 *
1072 * @fmt: the format string
1073 * @type of the token returned
1074 * @flags: various flags such as +, -, # tokens..
1075 * @field_width: overwritten width
1076 * @base: base of the number (octal, hex, ...)
1077 * @precision: precision of a number
1078 * @qualifier: qualifier of a number (long, size_t, ...)
1079 */
1080 static noinline_for_stack
1081 int format_decode(const char *fmt, struct printf_spec *spec)
1082 {
1083 const char *start = fmt;
1084
1085 /* we finished early by reading the field width */
1086 if (spec->type == FORMAT_TYPE_WIDTH) {
1087 if (spec->field_width < 0) {
1088 spec->field_width = -spec->field_width;
1089 spec->flags |= LEFT;
1090 }
1091 spec->type = FORMAT_TYPE_NONE;
1092 goto precision;
1093 }
1094
1095 /* we finished early by reading the precision */
1096 if (spec->type == FORMAT_TYPE_PRECISION) {
1097 if (spec->precision < 0)
1098 spec->precision = 0;
1099
1100 spec->type = FORMAT_TYPE_NONE;
1101 goto qualifier;
1102 }
1103
1104 /* By default */
1105 spec->type = FORMAT_TYPE_NONE;
1106
1107 for (; *fmt ; ++fmt) {
1108 if (*fmt == '%')
1109 break;
1110 }
1111
1112 /* Return the current non-format string */
1113 if (fmt != start || !*fmt)
1114 return fmt - start;
1115
1116 /* Process flags */
1117 spec->flags = 0;
1118
1119 while (1) { /* this also skips first '%' */
1120 bool found = true;
1121
1122 ++fmt;
1123
1124 switch (*fmt) {
1125 case '-': spec->flags |= LEFT; break;
1126 case '+': spec->flags |= PLUS; break;
1127 case ' ': spec->flags |= SPACE; break;
1128 case '#': spec->flags |= SPECIAL; break;
1129 case '0': spec->flags |= ZEROPAD; break;
1130 default: found = false;
1131 }
1132
1133 if (!found)
1134 break;
1135 }
1136
1137 /* get field width */
1138 spec->field_width = -1;
1139
1140 if (isdigit(*fmt))
1141 spec->field_width = skip_atoi(&fmt);
1142 else if (*fmt == '*') {
1143 /* it's the next argument */
1144 spec->type = FORMAT_TYPE_WIDTH;
1145 return ++fmt - start;
1146 }
1147
1148 precision:
1149 /* get the precision */
1150 spec->precision = -1;
1151 if (*fmt == '.') {
1152 ++fmt;
1153 if (isdigit(*fmt)) {
1154 spec->precision = skip_atoi(&fmt);
1155 if (spec->precision < 0)
1156 spec->precision = 0;
1157 } else if (*fmt == '*') {
1158 /* it's the next argument */
1159 spec->type = FORMAT_TYPE_PRECISION;
1160 return ++fmt - start;
1161 }
1162 }
1163
1164 qualifier:
1165 /* get the conversion qualifier */
1166 spec->qualifier = -1;
1167 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1168 _tolower(*fmt) == 'z' || *fmt == 't') {
1169 spec->qualifier = *fmt++;
1170 if (unlikely(spec->qualifier == *fmt)) {
1171 if (spec->qualifier == 'l') {
1172 spec->qualifier = 'L';
1173 ++fmt;
1174 } else if (spec->qualifier == 'h') {
1175 spec->qualifier = 'H';
1176 ++fmt;
1177 }
1178 }
1179 }
1180
1181 /* default base */
1182 spec->base = 10;
1183 switch (*fmt) {
1184 case 'c':
1185 spec->type = FORMAT_TYPE_CHAR;
1186 return ++fmt - start;
1187
1188 case 's':
1189 spec->type = FORMAT_TYPE_STR;
1190 return ++fmt - start;
1191
1192 case 'p':
1193 spec->type = FORMAT_TYPE_PTR;
1194 return fmt - start;
1195 /* skip alnum */
1196
1197 case 'n':
1198 spec->type = FORMAT_TYPE_NRCHARS;
1199 return ++fmt - start;
1200
1201 case '%':
1202 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1203 return ++fmt - start;
1204
1205 /* integer number formats - set up the flags and "break" */
1206 case 'o':
1207 spec->base = 8;
1208 break;
1209
1210 case 'x':
1211 spec->flags |= SMALL;
1212
1213 case 'X':
1214 spec->base = 16;
1215 break;
1216
1217 case 'd':
1218 case 'i':
1219 spec->flags |= SIGN;
1220 case 'u':
1221 break;
1222
1223 default:
1224 spec->type = FORMAT_TYPE_INVALID;
1225 return fmt - start;
1226 }
1227
1228 if (spec->qualifier == 'L')
1229 spec->type = FORMAT_TYPE_LONG_LONG;
1230 else if (spec->qualifier == 'l') {
1231 if (spec->flags & SIGN)
1232 spec->type = FORMAT_TYPE_LONG;
1233 else
1234 spec->type = FORMAT_TYPE_ULONG;
1235 } else if (_tolower(spec->qualifier) == 'z') {
1236 spec->type = FORMAT_TYPE_SIZE_T;
1237 } else if (spec->qualifier == 't') {
1238 spec->type = FORMAT_TYPE_PTRDIFF;
1239 } else if (spec->qualifier == 'H') {
1240 if (spec->flags & SIGN)
1241 spec->type = FORMAT_TYPE_BYTE;
1242 else
1243 spec->type = FORMAT_TYPE_UBYTE;
1244 } else if (spec->qualifier == 'h') {
1245 if (spec->flags & SIGN)
1246 spec->type = FORMAT_TYPE_SHORT;
1247 else
1248 spec->type = FORMAT_TYPE_USHORT;
1249 } else {
1250 if (spec->flags & SIGN)
1251 spec->type = FORMAT_TYPE_INT;
1252 else
1253 spec->type = FORMAT_TYPE_UINT;
1254 }
1255
1256 return ++fmt - start;
1257 }
1258
1259 /**
1260 * vsnprintf - Format a string and place it in a buffer
1261 * @buf: The buffer to place the result into
1262 * @size: The size of the buffer, including the trailing null space
1263 * @fmt: The format string to use
1264 * @args: Arguments for the format string
1265 *
1266 * This function follows C99 vsnprintf, but has some extensions:
1267 * %pS output the name of a text symbol with offset
1268 * %ps output the name of a text symbol without offset
1269 * %pF output the name of a function pointer with its offset
1270 * %pf output the name of a function pointer without its offset
1271 * %pB output the name of a backtrace symbol with its offset
1272 * %pR output the address range in a struct resource with decoded flags
1273 * %pr output the address range in a struct resource with raw flags
1274 * %pM output a 6-byte MAC address with colons
1275 * %pm output a 6-byte MAC address without colons
1276 * %pI4 print an IPv4 address without leading zeros
1277 * %pi4 print an IPv4 address with leading zeros
1278 * %pI6 print an IPv6 address with colons
1279 * %pi6 print an IPv6 address without colons
1280 * %pI6c print an IPv6 address as specified by RFC 5952
1281 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1282 * case.
1283 * %n is ignored
1284 *
1285 * The return value is the number of characters which would
1286 * be generated for the given input, excluding the trailing
1287 * '\0', as per ISO C99. If you want to have the exact
1288 * number of characters written into @buf as return value
1289 * (not including the trailing '\0'), use vscnprintf(). If the
1290 * return is greater than or equal to @size, the resulting
1291 * string is truncated.
1292 *
1293 * If you're not already dealing with a va_list consider using snprintf().
1294 */
1295 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1296 {
1297 unsigned long long num;
1298 char *str, *end;
1299 struct printf_spec spec = {0};
1300
1301 /* Reject out-of-range values early. Large positive sizes are
1302 used for unknown buffer sizes. */
1303 if (WARN_ON_ONCE((int) size < 0))
1304 return 0;
1305
1306 str = buf;
1307 end = buf + size;
1308
1309 /* Make sure end is always >= buf */
1310 if (end < buf) {
1311 end = ((void *)-1);
1312 size = end - buf;
1313 }
1314
1315 while (*fmt) {
1316 const char *old_fmt = fmt;
1317 int read = format_decode(fmt, &spec);
1318
1319 fmt += read;
1320
1321 switch (spec.type) {
1322 case FORMAT_TYPE_NONE: {
1323 int copy = read;
1324 if (str < end) {
1325 if (copy > end - str)
1326 copy = end - str;
1327 memcpy(str, old_fmt, copy);
1328 }
1329 str += read;
1330 break;
1331 }
1332
1333 case FORMAT_TYPE_WIDTH:
1334 spec.field_width = va_arg(args, int);
1335 break;
1336
1337 case FORMAT_TYPE_PRECISION:
1338 spec.precision = va_arg(args, int);
1339 break;
1340
1341 case FORMAT_TYPE_CHAR: {
1342 char c;
1343
1344 if (!(spec.flags & LEFT)) {
1345 while (--spec.field_width > 0) {
1346 if (str < end)
1347 *str = ' ';
1348 ++str;
1349
1350 }
1351 }
1352 c = (unsigned char) va_arg(args, int);
1353 if (str < end)
1354 *str = c;
1355 ++str;
1356 while (--spec.field_width > 0) {
1357 if (str < end)
1358 *str = ' ';
1359 ++str;
1360 }
1361 break;
1362 }
1363
1364 case FORMAT_TYPE_STR:
1365 str = string(str, end, va_arg(args, char *), spec);
1366 break;
1367
1368 case FORMAT_TYPE_PTR:
1369 str = pointer(fmt+1, str, end, va_arg(args, void *),
1370 spec);
1371 while (isalnum(*fmt))
1372 fmt++;
1373 break;
1374
1375 case FORMAT_TYPE_PERCENT_CHAR:
1376 if (str < end)
1377 *str = '%';
1378 ++str;
1379 break;
1380
1381 case FORMAT_TYPE_INVALID:
1382 if (str < end)
1383 *str = '%';
1384 ++str;
1385 break;
1386
1387 case FORMAT_TYPE_NRCHARS: {
1388 u8 qualifier = spec.qualifier;
1389
1390 if (qualifier == 'l') {
1391 long *ip = va_arg(args, long *);
1392 *ip = (str - buf);
1393 } else if (_tolower(qualifier) == 'z') {
1394 size_t *ip = va_arg(args, size_t *);
1395 *ip = (str - buf);
1396 } else {
1397 int *ip = va_arg(args, int *);
1398 *ip = (str - buf);
1399 }
1400 break;
1401 }
1402
1403 default:
1404 switch (spec.type) {
1405 case FORMAT_TYPE_LONG_LONG:
1406 num = va_arg(args, long long);
1407 break;
1408 case FORMAT_TYPE_ULONG:
1409 num = va_arg(args, unsigned long);
1410 break;
1411 case FORMAT_TYPE_LONG:
1412 num = va_arg(args, long);
1413 break;
1414 case FORMAT_TYPE_SIZE_T:
1415 num = va_arg(args, size_t);
1416 break;
1417 case FORMAT_TYPE_PTRDIFF:
1418 num = va_arg(args, ptrdiff_t);
1419 break;
1420 case FORMAT_TYPE_UBYTE:
1421 num = (unsigned char) va_arg(args, int);
1422 break;
1423 case FORMAT_TYPE_BYTE:
1424 num = (signed char) va_arg(args, int);
1425 break;
1426 case FORMAT_TYPE_USHORT:
1427 num = (unsigned short) va_arg(args, int);
1428 break;
1429 case FORMAT_TYPE_SHORT:
1430 num = (short) va_arg(args, int);
1431 break;
1432 case FORMAT_TYPE_INT:
1433 num = (int) va_arg(args, int);
1434 break;
1435 default:
1436 num = va_arg(args, unsigned int);
1437 }
1438
1439 str = number(str, end, num, spec);
1440 }
1441 }
1442
1443 if (size > 0) {
1444 if (str < end)
1445 *str = '\0';
1446 else
1447 end[-1] = '\0';
1448 }
1449
1450 /* the trailing null byte doesn't count towards the total */
1451 return str-buf;
1452
1453 }
1454 EXPORT_SYMBOL(vsnprintf);
1455
1456 /**
1457 * vscnprintf - Format a string and place it in a buffer
1458 * @buf: The buffer to place the result into
1459 * @size: The size of the buffer, including the trailing null space
1460 * @fmt: The format string to use
1461 * @args: Arguments for the format string
1462 *
1463 * The return value is the number of characters which have been written into
1464 * the @buf not including the trailing '\0'. If @size is == 0 the function
1465 * returns 0.
1466 *
1467 * If you're not already dealing with a va_list consider using scnprintf().
1468 *
1469 * See the vsnprintf() documentation for format string extensions over C99.
1470 */
1471 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1472 {
1473 int i;
1474
1475 i = vsnprintf(buf, size, fmt, args);
1476
1477 if (likely(i < size))
1478 return i;
1479 if (size != 0)
1480 return size - 1;
1481 return 0;
1482 }
1483 EXPORT_SYMBOL(vscnprintf);
1484
1485 /**
1486 * snprintf - Format a string and place it in a buffer
1487 * @buf: The buffer to place the result into
1488 * @size: The size of the buffer, including the trailing null space
1489 * @fmt: The format string to use
1490 * @...: Arguments for the format string
1491 *
1492 * The return value is the number of characters which would be
1493 * generated for the given input, excluding the trailing null,
1494 * as per ISO C99. If the return is greater than or equal to
1495 * @size, the resulting string is truncated.
1496 *
1497 * See the vsnprintf() documentation for format string extensions over C99.
1498 */
1499 int snprintf(char *buf, size_t size, const char *fmt, ...)
1500 {
1501 va_list args;
1502 int i;
1503
1504 va_start(args, fmt);
1505 i = vsnprintf(buf, size, fmt, args);
1506 va_end(args);
1507
1508 return i;
1509 }
1510 EXPORT_SYMBOL(snprintf);
1511
1512 /**
1513 * scnprintf - Format a string and place it in a buffer
1514 * @buf: The buffer to place the result into
1515 * @size: The size of the buffer, including the trailing null space
1516 * @fmt: The format string to use
1517 * @...: Arguments for the format string
1518 *
1519 * The return value is the number of characters written into @buf not including
1520 * the trailing '\0'. If @size is == 0 the function returns 0.
1521 */
1522
1523 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1524 {
1525 va_list args;
1526 int i;
1527
1528 va_start(args, fmt);
1529 i = vscnprintf(buf, size, fmt, args);
1530 va_end(args);
1531
1532 return i;
1533 }
1534 EXPORT_SYMBOL(scnprintf);
1535
1536 /**
1537 * vsprintf - Format a string and place it in a buffer
1538 * @buf: The buffer to place the result into
1539 * @fmt: The format string to use
1540 * @args: Arguments for the format string
1541 *
1542 * The function returns the number of characters written
1543 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1544 * buffer overflows.
1545 *
1546 * If you're not already dealing with a va_list consider using sprintf().
1547 *
1548 * See the vsnprintf() documentation for format string extensions over C99.
1549 */
1550 int vsprintf(char *buf, const char *fmt, va_list args)
1551 {
1552 return vsnprintf(buf, INT_MAX, fmt, args);
1553 }
1554 EXPORT_SYMBOL(vsprintf);
1555
1556 /**
1557 * sprintf - Format a string and place it in a buffer
1558 * @buf: The buffer to place the result into
1559 * @fmt: The format string to use
1560 * @...: Arguments for the format string
1561 *
1562 * The function returns the number of characters written
1563 * into @buf. Use snprintf() or scnprintf() in order to avoid
1564 * buffer overflows.
1565 *
1566 * See the vsnprintf() documentation for format string extensions over C99.
1567 */
1568 int sprintf(char *buf, const char *fmt, ...)
1569 {
1570 va_list args;
1571 int i;
1572
1573 va_start(args, fmt);
1574 i = vsnprintf(buf, INT_MAX, fmt, args);
1575 va_end(args);
1576
1577 return i;
1578 }
1579 EXPORT_SYMBOL(sprintf);
1580
1581 #ifdef CONFIG_BINARY_PRINTF
1582 /*
1583 * bprintf service:
1584 * vbin_printf() - VA arguments to binary data
1585 * bstr_printf() - Binary data to text string
1586 */
1587
1588 /**
1589 * vbin_printf - Parse a format string and place args' binary value in a buffer
1590 * @bin_buf: The buffer to place args' binary value
1591 * @size: The size of the buffer(by words(32bits), not characters)
1592 * @fmt: The format string to use
1593 * @args: Arguments for the format string
1594 *
1595 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1596 * is skiped.
1597 *
1598 * The return value is the number of words(32bits) which would be generated for
1599 * the given input.
1600 *
1601 * NOTE:
1602 * If the return value is greater than @size, the resulting bin_buf is NOT
1603 * valid for bstr_printf().
1604 */
1605 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1606 {
1607 struct printf_spec spec = {0};
1608 char *str, *end;
1609
1610 str = (char *)bin_buf;
1611 end = (char *)(bin_buf + size);
1612
1613 #define save_arg(type) \
1614 do { \
1615 if (sizeof(type) == 8) { \
1616 unsigned long long value; \
1617 str = PTR_ALIGN(str, sizeof(u32)); \
1618 value = va_arg(args, unsigned long long); \
1619 if (str + sizeof(type) <= end) { \
1620 *(u32 *)str = *(u32 *)&value; \
1621 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1622 } \
1623 } else { \
1624 unsigned long value; \
1625 str = PTR_ALIGN(str, sizeof(type)); \
1626 value = va_arg(args, int); \
1627 if (str + sizeof(type) <= end) \
1628 *(typeof(type) *)str = (type)value; \
1629 } \
1630 str += sizeof(type); \
1631 } while (0)
1632
1633 while (*fmt) {
1634 int read = format_decode(fmt, &spec);
1635
1636 fmt += read;
1637
1638 switch (spec.type) {
1639 case FORMAT_TYPE_NONE:
1640 case FORMAT_TYPE_INVALID:
1641 case FORMAT_TYPE_PERCENT_CHAR:
1642 break;
1643
1644 case FORMAT_TYPE_WIDTH:
1645 case FORMAT_TYPE_PRECISION:
1646 save_arg(int);
1647 break;
1648
1649 case FORMAT_TYPE_CHAR:
1650 save_arg(char);
1651 break;
1652
1653 case FORMAT_TYPE_STR: {
1654 const char *save_str = va_arg(args, char *);
1655 size_t len;
1656
1657 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1658 || (unsigned long)save_str < PAGE_SIZE)
1659 save_str = "(null)";
1660 len = strlen(save_str) + 1;
1661 if (str + len < end)
1662 memcpy(str, save_str, len);
1663 str += len;
1664 break;
1665 }
1666
1667 case FORMAT_TYPE_PTR:
1668 save_arg(void *);
1669 /* skip all alphanumeric pointer suffixes */
1670 while (isalnum(*fmt))
1671 fmt++;
1672 break;
1673
1674 case FORMAT_TYPE_NRCHARS: {
1675 /* skip %n 's argument */
1676 u8 qualifier = spec.qualifier;
1677 void *skip_arg;
1678 if (qualifier == 'l')
1679 skip_arg = va_arg(args, long *);
1680 else if (_tolower(qualifier) == 'z')
1681 skip_arg = va_arg(args, size_t *);
1682 else
1683 skip_arg = va_arg(args, int *);
1684 break;
1685 }
1686
1687 default:
1688 switch (spec.type) {
1689
1690 case FORMAT_TYPE_LONG_LONG:
1691 save_arg(long long);
1692 break;
1693 case FORMAT_TYPE_ULONG:
1694 case FORMAT_TYPE_LONG:
1695 save_arg(unsigned long);
1696 break;
1697 case FORMAT_TYPE_SIZE_T:
1698 save_arg(size_t);
1699 break;
1700 case FORMAT_TYPE_PTRDIFF:
1701 save_arg(ptrdiff_t);
1702 break;
1703 case FORMAT_TYPE_UBYTE:
1704 case FORMAT_TYPE_BYTE:
1705 save_arg(char);
1706 break;
1707 case FORMAT_TYPE_USHORT:
1708 case FORMAT_TYPE_SHORT:
1709 save_arg(short);
1710 break;
1711 default:
1712 save_arg(int);
1713 }
1714 }
1715 }
1716
1717 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1718 #undef save_arg
1719 }
1720 EXPORT_SYMBOL_GPL(vbin_printf);
1721
1722 /**
1723 * bstr_printf - Format a string from binary arguments and place it in a buffer
1724 * @buf: The buffer to place the result into
1725 * @size: The size of the buffer, including the trailing null space
1726 * @fmt: The format string to use
1727 * @bin_buf: Binary arguments for the format string
1728 *
1729 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1730 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1731 * a binary buffer that generated by vbin_printf.
1732 *
1733 * The format follows C99 vsnprintf, but has some extensions:
1734 * see vsnprintf comment for details.
1735 *
1736 * The return value is the number of characters which would
1737 * be generated for the given input, excluding the trailing
1738 * '\0', as per ISO C99. If you want to have the exact
1739 * number of characters written into @buf as return value
1740 * (not including the trailing '\0'), use vscnprintf(). If the
1741 * return is greater than or equal to @size, the resulting
1742 * string is truncated.
1743 */
1744 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1745 {
1746 struct printf_spec spec = {0};
1747 char *str, *end;
1748 const char *args = (const char *)bin_buf;
1749
1750 if (WARN_ON_ONCE((int) size < 0))
1751 return 0;
1752
1753 str = buf;
1754 end = buf + size;
1755
1756 #define get_arg(type) \
1757 ({ \
1758 typeof(type) value; \
1759 if (sizeof(type) == 8) { \
1760 args = PTR_ALIGN(args, sizeof(u32)); \
1761 *(u32 *)&value = *(u32 *)args; \
1762 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1763 } else { \
1764 args = PTR_ALIGN(args, sizeof(type)); \
1765 value = *(typeof(type) *)args; \
1766 } \
1767 args += sizeof(type); \
1768 value; \
1769 })
1770
1771 /* Make sure end is always >= buf */
1772 if (end < buf) {
1773 end = ((void *)-1);
1774 size = end - buf;
1775 }
1776
1777 while (*fmt) {
1778 const char *old_fmt = fmt;
1779 int read = format_decode(fmt, &spec);
1780
1781 fmt += read;
1782
1783 switch (spec.type) {
1784 case FORMAT_TYPE_NONE: {
1785 int copy = read;
1786 if (str < end) {
1787 if (copy > end - str)
1788 copy = end - str;
1789 memcpy(str, old_fmt, copy);
1790 }
1791 str += read;
1792 break;
1793 }
1794
1795 case FORMAT_TYPE_WIDTH:
1796 spec.field_width = get_arg(int);
1797 break;
1798
1799 case FORMAT_TYPE_PRECISION:
1800 spec.precision = get_arg(int);
1801 break;
1802
1803 case FORMAT_TYPE_CHAR: {
1804 char c;
1805
1806 if (!(spec.flags & LEFT)) {
1807 while (--spec.field_width > 0) {
1808 if (str < end)
1809 *str = ' ';
1810 ++str;
1811 }
1812 }
1813 c = (unsigned char) get_arg(char);
1814 if (str < end)
1815 *str = c;
1816 ++str;
1817 while (--spec.field_width > 0) {
1818 if (str < end)
1819 *str = ' ';
1820 ++str;
1821 }
1822 break;
1823 }
1824
1825 case FORMAT_TYPE_STR: {
1826 const char *str_arg = args;
1827 args += strlen(str_arg) + 1;
1828 str = string(str, end, (char *)str_arg, spec);
1829 break;
1830 }
1831
1832 case FORMAT_TYPE_PTR:
1833 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1834 while (isalnum(*fmt))
1835 fmt++;
1836 break;
1837
1838 case FORMAT_TYPE_PERCENT_CHAR:
1839 case FORMAT_TYPE_INVALID:
1840 if (str < end)
1841 *str = '%';
1842 ++str;
1843 break;
1844
1845 case FORMAT_TYPE_NRCHARS:
1846 /* skip */
1847 break;
1848
1849 default: {
1850 unsigned long long num;
1851
1852 switch (spec.type) {
1853
1854 case FORMAT_TYPE_LONG_LONG:
1855 num = get_arg(long long);
1856 break;
1857 case FORMAT_TYPE_ULONG:
1858 case FORMAT_TYPE_LONG:
1859 num = get_arg(unsigned long);
1860 break;
1861 case FORMAT_TYPE_SIZE_T:
1862 num = get_arg(size_t);
1863 break;
1864 case FORMAT_TYPE_PTRDIFF:
1865 num = get_arg(ptrdiff_t);
1866 break;
1867 case FORMAT_TYPE_UBYTE:
1868 num = get_arg(unsigned char);
1869 break;
1870 case FORMAT_TYPE_BYTE:
1871 num = get_arg(signed char);
1872 break;
1873 case FORMAT_TYPE_USHORT:
1874 num = get_arg(unsigned short);
1875 break;
1876 case FORMAT_TYPE_SHORT:
1877 num = get_arg(short);
1878 break;
1879 case FORMAT_TYPE_UINT:
1880 num = get_arg(unsigned int);
1881 break;
1882 default:
1883 num = get_arg(int);
1884 }
1885
1886 str = number(str, end, num, spec);
1887 } /* default: */
1888 } /* switch(spec.type) */
1889 } /* while(*fmt) */
1890
1891 if (size > 0) {
1892 if (str < end)
1893 *str = '\0';
1894 else
1895 end[-1] = '\0';
1896 }
1897
1898 #undef get_arg
1899
1900 /* the trailing null byte doesn't count towards the total */
1901 return str - buf;
1902 }
1903 EXPORT_SYMBOL_GPL(bstr_printf);
1904
1905 /**
1906 * bprintf - Parse a format string and place args' binary value in a buffer
1907 * @bin_buf: The buffer to place args' binary value
1908 * @size: The size of the buffer(by words(32bits), not characters)
1909 * @fmt: The format string to use
1910 * @...: Arguments for the format string
1911 *
1912 * The function returns the number of words(u32) written
1913 * into @bin_buf.
1914 */
1915 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1916 {
1917 va_list args;
1918 int ret;
1919
1920 va_start(args, fmt);
1921 ret = vbin_printf(bin_buf, size, fmt, args);
1922 va_end(args);
1923
1924 return ret;
1925 }
1926 EXPORT_SYMBOL_GPL(bprintf);
1927
1928 #endif /* CONFIG_BINARY_PRINTF */
1929
1930 /**
1931 * vsscanf - Unformat a buffer into a list of arguments
1932 * @buf: input buffer
1933 * @fmt: format of buffer
1934 * @args: arguments
1935 */
1936 int vsscanf(const char *buf, const char *fmt, va_list args)
1937 {
1938 const char *str = buf;
1939 char *next;
1940 char digit;
1941 int num = 0;
1942 u8 qualifier;
1943 u8 base;
1944 s16 field_width;
1945 bool is_sign;
1946
1947 while (*fmt && *str) {
1948 /* skip any white space in format */
1949 /* white space in format matchs any amount of
1950 * white space, including none, in the input.
1951 */
1952 if (isspace(*fmt)) {
1953 fmt = skip_spaces(++fmt);
1954 str = skip_spaces(str);
1955 }
1956
1957 /* anything that is not a conversion must match exactly */
1958 if (*fmt != '%' && *fmt) {
1959 if (*fmt++ != *str++)
1960 break;
1961 continue;
1962 }
1963
1964 if (!*fmt)
1965 break;
1966 ++fmt;
1967
1968 /* skip this conversion.
1969 * advance both strings to next white space
1970 */
1971 if (*fmt == '*') {
1972 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1973 fmt++;
1974 while (!isspace(*str) && *str)
1975 str++;
1976 continue;
1977 }
1978
1979 /* get field width */
1980 field_width = -1;
1981 if (isdigit(*fmt))
1982 field_width = skip_atoi(&fmt);
1983
1984 /* get conversion qualifier */
1985 qualifier = -1;
1986 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1987 _tolower(*fmt) == 'z') {
1988 qualifier = *fmt++;
1989 if (unlikely(qualifier == *fmt)) {
1990 if (qualifier == 'h') {
1991 qualifier = 'H';
1992 fmt++;
1993 } else if (qualifier == 'l') {
1994 qualifier = 'L';
1995 fmt++;
1996 }
1997 }
1998 }
1999
2000 if (!*fmt || !*str)
2001 break;
2002
2003 base = 10;
2004 is_sign = 0;
2005
2006 switch (*fmt++) {
2007 case 'c':
2008 {
2009 char *s = (char *)va_arg(args, char*);
2010 if (field_width == -1)
2011 field_width = 1;
2012 do {
2013 *s++ = *str++;
2014 } while (--field_width > 0 && *str);
2015 num++;
2016 }
2017 continue;
2018 case 's':
2019 {
2020 char *s = (char *)va_arg(args, char *);
2021 if (field_width == -1)
2022 field_width = SHRT_MAX;
2023 /* first, skip leading white space in buffer */
2024 str = skip_spaces(str);
2025
2026 /* now copy until next white space */
2027 while (*str && !isspace(*str) && field_width--)
2028 *s++ = *str++;
2029 *s = '\0';
2030 num++;
2031 }
2032 continue;
2033 case 'n':
2034 /* return number of characters read so far */
2035 {
2036 int *i = (int *)va_arg(args, int*);
2037 *i = str - buf;
2038 }
2039 continue;
2040 case 'o':
2041 base = 8;
2042 break;
2043 case 'x':
2044 case 'X':
2045 base = 16;
2046 break;
2047 case 'i':
2048 base = 0;
2049 case 'd':
2050 is_sign = 1;
2051 case 'u':
2052 break;
2053 case '%':
2054 /* looking for '%' in str */
2055 if (*str++ != '%')
2056 return num;
2057 continue;
2058 default:
2059 /* invalid format; stop here */
2060 return num;
2061 }
2062
2063 /* have some sort of integer conversion.
2064 * first, skip white space in buffer.
2065 */
2066 str = skip_spaces(str);
2067
2068 digit = *str;
2069 if (is_sign && digit == '-')
2070 digit = *(str + 1);
2071
2072 if (!digit
2073 || (base == 16 && !isxdigit(digit))
2074 || (base == 10 && !isdigit(digit))
2075 || (base == 8 && (!isdigit(digit) || digit > '7'))
2076 || (base == 0 && !isdigit(digit)))
2077 break;
2078
2079 switch (qualifier) {
2080 case 'H': /* that's 'hh' in format */
2081 if (is_sign) {
2082 signed char *s = (signed char *)va_arg(args, signed char *);
2083 *s = (signed char)simple_strtol(str, &next, base);
2084 } else {
2085 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
2086 *s = (unsigned char)simple_strtoul(str, &next, base);
2087 }
2088 break;
2089 case 'h':
2090 if (is_sign) {
2091 short *s = (short *)va_arg(args, short *);
2092 *s = (short)simple_strtol(str, &next, base);
2093 } else {
2094 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
2095 *s = (unsigned short)simple_strtoul(str, &next, base);
2096 }
2097 break;
2098 case 'l':
2099 if (is_sign) {
2100 long *l = (long *)va_arg(args, long *);
2101 *l = simple_strtol(str, &next, base);
2102 } else {
2103 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2104 *l = simple_strtoul(str, &next, base);
2105 }
2106 break;
2107 case 'L':
2108 if (is_sign) {
2109 long long *l = (long long *)va_arg(args, long long *);
2110 *l = simple_strtoll(str, &next, base);
2111 } else {
2112 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2113 *l = simple_strtoull(str, &next, base);
2114 }
2115 break;
2116 case 'Z':
2117 case 'z':
2118 {
2119 size_t *s = (size_t *)va_arg(args, size_t *);
2120 *s = (size_t)simple_strtoul(str, &next, base);
2121 }
2122 break;
2123 default:
2124 if (is_sign) {
2125 int *i = (int *)va_arg(args, int *);
2126 *i = (int)simple_strtol(str, &next, base);
2127 } else {
2128 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2129 *i = (unsigned int)simple_strtoul(str, &next, base);
2130 }
2131 break;
2132 }
2133 num++;
2134
2135 if (!next)
2136 break;
2137 str = next;
2138 }
2139
2140 /*
2141 * Now we've come all the way through so either the input string or the
2142 * format ended. In the former case, there can be a %n at the current
2143 * position in the format that needs to be filled.
2144 */
2145 if (*fmt == '%' && *(fmt + 1) == 'n') {
2146 int *p = (int *)va_arg(args, int *);
2147 *p = str - buf;
2148 }
2149
2150 return num;
2151 }
2152 EXPORT_SYMBOL(vsscanf);
2153
2154 /**
2155 * sscanf - Unformat a buffer into a list of arguments
2156 * @buf: input buffer
2157 * @fmt: formatting of buffer
2158 * @...: resulting arguments
2159 */
2160 int sscanf(const char *buf, const char *fmt, ...)
2161 {
2162 va_list args;
2163 int i;
2164
2165 va_start(args, fmt);
2166 i = vsscanf(buf, fmt, args);
2167 va_end(args);
2168
2169 return i;
2170 }
2171 EXPORT_SYMBOL(sscanf);
Linus' kernel tree