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base/platform: Simplifications for NULL platform data/resources handling
[linux-2.6.git] / lib / vsprintf.c
blob7af9d841c43beea318540340739ac3432b87ed12
1 /*
2 * linux/lib/vsprintf.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8 /*
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
10 */
11
12 /*
13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
16 * - scnprintf and vscnprintf
17 */
18
19 #include <stdarg.h>
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/ctype.h>
24 #include <linux/kernel.h>
25 #include <linux/kallsyms.h>
26 #include <linux/uaccess.h>
27 #include <linux/ioport.h>
28 #include <net/addrconf.h>
29
30 #include <asm/page.h> /* for PAGE_SIZE */
31 #include <asm/div64.h>
32 #include <asm/sections.h> /* for dereference_function_descriptor() */
33
34 /* Works only for digits and letters, but small and fast */
35 #define TOLOWER(x) ((x) | 0x20)
36
37 static unsigned int simple_guess_base(const char *cp)
38 {
39 if (cp[0] == '0') {
40 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
41 return 16;
42 else
43 return 8;
44 } else {
45 return 10;
46 }
47 }
48
49 /**
50 * simple_strtoull - convert a string to an unsigned long long
51 * @cp: The start of the string
52 * @endp: A pointer to the end of the parsed string will be placed here
53 * @base: The number base to use
54 */
55 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
56 {
57 unsigned long long result = 0;
58
59 if (!base)
60 base = simple_guess_base(cp);
61
62 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
63 cp += 2;
64
65 while (isxdigit(*cp)) {
66 unsigned int value;
67
68 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
69 if (value >= base)
70 break;
71 result = result * base + value;
72 cp++;
73 }
74 if (endp)
75 *endp = (char *)cp;
76
77 return result;
78 }
79 EXPORT_SYMBOL(simple_strtoull);
80
81 /**
82 * simple_strtoul - convert a string to an unsigned long
83 * @cp: The start of the string
84 * @endp: A pointer to the end of the parsed string will be placed here
85 * @base: The number base to use
86 */
87 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
88 {
89 return simple_strtoull(cp, endp, base);
90 }
91 EXPORT_SYMBOL(simple_strtoul);
92
93 /**
94 * simple_strtol - convert a string to a signed long
95 * @cp: The start of the string
96 * @endp: A pointer to the end of the parsed string will be placed here
97 * @base: The number base to use
98 */
99 long simple_strtol(const char *cp, char **endp, unsigned int base)
100 {
101 if (*cp == '-')
102 return -simple_strtoul(cp + 1, endp, base);
103
104 return simple_strtoul(cp, endp, base);
105 }
106 EXPORT_SYMBOL(simple_strtol);
107
108 /**
109 * simple_strtoll - convert a string to a signed long long
110 * @cp: The start of the string
111 * @endp: A pointer to the end of the parsed string will be placed here
112 * @base: The number base to use
113 */
114 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
115 {
116 if (*cp == '-')
117 return -simple_strtoull(cp + 1, endp, base);
118
119 return simple_strtoull(cp, endp, base);
120 }
121 EXPORT_SYMBOL(simple_strtoll);
122
123 /**
124 * strict_strtoul - convert a string to an unsigned long strictly
125 * @cp: The string to be converted
126 * @base: The number base to use
127 * @res: The converted result value
128 *
129 * strict_strtoul converts a string to an unsigned long only if the
130 * string is really an unsigned long string, any string containing
131 * any invalid char at the tail will be rejected and -EINVAL is returned,
132 * only a newline char at the tail is acceptible because people generally
133 * change a module parameter in the following way:
134 *
135 * echo 1024 > /sys/module/e1000/parameters/copybreak
136 *
137 * echo will append a newline to the tail.
138 *
139 * It returns 0 if conversion is successful and *res is set to the converted
140 * value, otherwise it returns -EINVAL and *res is set to 0.
141 *
142 * simple_strtoul just ignores the successive invalid characters and
143 * return the converted value of prefix part of the string.
144 */
145 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
146 {
147 char *tail;
148 unsigned long val;
149
150 *res = 0;
151 if (!*cp)
152 return -EINVAL;
153
154 val = simple_strtoul(cp, &tail, base);
155 if (tail == cp)
156 return -EINVAL;
157
158 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
159 *res = val;
160 return 0;
161 }
162
163 return -EINVAL;
164 }
165 EXPORT_SYMBOL(strict_strtoul);
166
167 /**
168 * strict_strtol - convert a string to a long strictly
169 * @cp: The string to be converted
170 * @base: The number base to use
171 * @res: The converted result value
172 *
173 * strict_strtol is similiar to strict_strtoul, but it allows the first
174 * character of a string is '-'.
175 *
176 * It returns 0 if conversion is successful and *res is set to the converted
177 * value, otherwise it returns -EINVAL and *res is set to 0.
178 */
179 int strict_strtol(const char *cp, unsigned int base, long *res)
180 {
181 int ret;
182 if (*cp == '-') {
183 ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
184 if (!ret)
185 *res = -(*res);
186 } else {
187 ret = strict_strtoul(cp, base, (unsigned long *)res);
188 }
189
190 return ret;
191 }
192 EXPORT_SYMBOL(strict_strtol);
193
194 /**
195 * strict_strtoull - convert a string to an unsigned long long strictly
196 * @cp: The string to be converted
197 * @base: The number base to use
198 * @res: The converted result value
199 *
200 * strict_strtoull converts a string to an unsigned long long only if the
201 * string is really an unsigned long long string, any string containing
202 * any invalid char at the tail will be rejected and -EINVAL is returned,
203 * only a newline char at the tail is acceptible because people generally
204 * change a module parameter in the following way:
205 *
206 * echo 1024 > /sys/module/e1000/parameters/copybreak
207 *
208 * echo will append a newline to the tail of the string.
209 *
210 * It returns 0 if conversion is successful and *res is set to the converted
211 * value, otherwise it returns -EINVAL and *res is set to 0.
212 *
213 * simple_strtoull just ignores the successive invalid characters and
214 * return the converted value of prefix part of the string.
215 */
216 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
217 {
218 char *tail;
219 unsigned long long val;
220
221 *res = 0;
222 if (!*cp)
223 return -EINVAL;
224
225 val = simple_strtoull(cp, &tail, base);
226 if (tail == cp)
227 return -EINVAL;
228 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
229 *res = val;
230 return 0;
231 }
232
233 return -EINVAL;
234 }
235 EXPORT_SYMBOL(strict_strtoull);
236
237 /**
238 * strict_strtoll - convert a string to a long long strictly
239 * @cp: The string to be converted
240 * @base: The number base to use
241 * @res: The converted result value
242 *
243 * strict_strtoll is similiar to strict_strtoull, but it allows the first
244 * character of a string is '-'.
245 *
246 * It returns 0 if conversion is successful and *res is set to the converted
247 * value, otherwise it returns -EINVAL and *res is set to 0.
248 */
249 int strict_strtoll(const char *cp, unsigned int base, long long *res)
250 {
251 int ret;
252 if (*cp == '-') {
253 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
254 if (!ret)
255 *res = -(*res);
256 } else {
257 ret = strict_strtoull(cp, base, (unsigned long long *)res);
258 }
259
260 return ret;
261 }
262 EXPORT_SYMBOL(strict_strtoll);
263
264 static noinline_for_stack
265 int skip_atoi(const char **s)
266 {
267 int i = 0;
268
269 while (isdigit(**s))
270 i = i*10 + *((*s)++) - '0';
271
272 return i;
273 }
274
275 /* Decimal conversion is by far the most typical, and is used
276 * for /proc and /sys data. This directly impacts e.g. top performance
277 * with many processes running. We optimize it for speed
278 * using code from
279 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
280 * (with permission from the author, Douglas W. Jones). */
281
282 /* Formats correctly any integer in [0,99999].
283 * Outputs from one to five digits depending on input.
284 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
285 static noinline_for_stack
286 char *put_dec_trunc(char *buf, unsigned q)
287 {
288 unsigned d3, d2, d1, d0;
289 d1 = (q>>4) & 0xf;
290 d2 = (q>>8) & 0xf;
291 d3 = (q>>12);
292
293 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
294 q = (d0 * 0xcd) >> 11;
295 d0 = d0 - 10*q;
296 *buf++ = d0 + '0'; /* least significant digit */
297 d1 = q + 9*d3 + 5*d2 + d1;
298 if (d1 != 0) {
299 q = (d1 * 0xcd) >> 11;
300 d1 = d1 - 10*q;
301 *buf++ = d1 + '0'; /* next digit */
302
303 d2 = q + 2*d2;
304 if ((d2 != 0) || (d3 != 0)) {
305 q = (d2 * 0xd) >> 7;
306 d2 = d2 - 10*q;
307 *buf++ = d2 + '0'; /* next digit */
308
309 d3 = q + 4*d3;
310 if (d3 != 0) {
311 q = (d3 * 0xcd) >> 11;
312 d3 = d3 - 10*q;
313 *buf++ = d3 + '0'; /* next digit */
314 if (q != 0)
315 *buf++ = q + '0'; /* most sign. digit */
316 }
317 }
318 }
319
320 return buf;
321 }
322 /* Same with if's removed. Always emits five digits */
323 static noinline_for_stack
324 char *put_dec_full(char *buf, unsigned q)
325 {
326 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
327 /* but anyway, gcc produces better code with full-sized ints */
328 unsigned d3, d2, d1, d0;
329 d1 = (q>>4) & 0xf;
330 d2 = (q>>8) & 0xf;
331 d3 = (q>>12);
332
333 /*
334 * Possible ways to approx. divide by 10
335 * gcc -O2 replaces multiply with shifts and adds
336 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
337 * (x * 0x67) >> 10: 1100111
338 * (x * 0x34) >> 9: 110100 - same
339 * (x * 0x1a) >> 8: 11010 - same
340 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
341 */
342 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
343 q = (d0 * 0xcd) >> 11;
344 d0 = d0 - 10*q;
345 *buf++ = d0 + '0';
346 d1 = q + 9*d3 + 5*d2 + d1;
347 q = (d1 * 0xcd) >> 11;
348 d1 = d1 - 10*q;
349 *buf++ = d1 + '0';
350
351 d2 = q + 2*d2;
352 q = (d2 * 0xd) >> 7;
353 d2 = d2 - 10*q;
354 *buf++ = d2 + '0';
355
356 d3 = q + 4*d3;
357 q = (d3 * 0xcd) >> 11; /* - shorter code */
358 /* q = (d3 * 0x67) >> 10; - would also work */
359 d3 = d3 - 10*q;
360 *buf++ = d3 + '0';
361 *buf++ = q + '0';
362
363 return buf;
364 }
365 /* No inlining helps gcc to use registers better */
366 static noinline_for_stack
367 char *put_dec(char *buf, unsigned long long num)
368 {
369 while (1) {
370 unsigned rem;
371 if (num < 100000)
372 return put_dec_trunc(buf, num);
373 rem = do_div(num, 100000);
374 buf = put_dec_full(buf, rem);
375 }
376 }
377
378 #define ZEROPAD 1 /* pad with zero */
379 #define SIGN 2 /* unsigned/signed long */
380 #define PLUS 4 /* show plus */
381 #define SPACE 8 /* space if plus */
382 #define LEFT 16 /* left justified */
383 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
384 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
385
386 enum format_type {
387 FORMAT_TYPE_NONE, /* Just a string part */
388 FORMAT_TYPE_WIDTH,
389 FORMAT_TYPE_PRECISION,
390 FORMAT_TYPE_CHAR,
391 FORMAT_TYPE_STR,
392 FORMAT_TYPE_PTR,
393 FORMAT_TYPE_PERCENT_CHAR,
394 FORMAT_TYPE_INVALID,
395 FORMAT_TYPE_LONG_LONG,
396 FORMAT_TYPE_ULONG,
397 FORMAT_TYPE_LONG,
398 FORMAT_TYPE_UBYTE,
399 FORMAT_TYPE_BYTE,
400 FORMAT_TYPE_USHORT,
401 FORMAT_TYPE_SHORT,
402 FORMAT_TYPE_UINT,
403 FORMAT_TYPE_INT,
404 FORMAT_TYPE_NRCHARS,
405 FORMAT_TYPE_SIZE_T,
406 FORMAT_TYPE_PTRDIFF
407 };
408
409 struct printf_spec {
410 u8 type; /* format_type enum */
411 u8 flags; /* flags to number() */
412 u8 base; /* number base, 8, 10 or 16 only */
413 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
414 s16 field_width; /* width of output field */
415 s16 precision; /* # of digits/chars */
416 };
417
418 static noinline_for_stack
419 char *number(char *buf, char *end, unsigned long long num,
420 struct printf_spec spec)
421 {
422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
424
425 char tmp[66];
426 char sign;
427 char locase;
428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
429 int i;
430
431 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
432 * produces same digits or (maybe lowercased) letters */
433 locase = (spec.flags & SMALL);
434 if (spec.flags & LEFT)
435 spec.flags &= ~ZEROPAD;
436 sign = 0;
437 if (spec.flags & SIGN) {
438 if ((signed long long)num < 0) {
439 sign = '-';
440 num = -(signed long long)num;
441 spec.field_width--;
442 } else if (spec.flags & PLUS) {
443 sign = '+';
444 spec.field_width--;
445 } else if (spec.flags & SPACE) {
446 sign = ' ';
447 spec.field_width--;
448 }
449 }
450 if (need_pfx) {
451 spec.field_width--;
452 if (spec.base == 16)
453 spec.field_width--;
454 }
455
456 /* generate full string in tmp[], in reverse order */
457 i = 0;
458 if (num == 0)
459 tmp[i++] = '0';
460 /* Generic code, for any base:
461 else do {
462 tmp[i++] = (digits[do_div(num,base)] | locase);
463 } while (num != 0);
464 */
465 else if (spec.base != 10) { /* 8 or 16 */
466 int mask = spec.base - 1;
467 int shift = 3;
468
469 if (spec.base == 16)
470 shift = 4;
471 do {
472 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
473 num >>= shift;
474 } while (num);
475 } else { /* base 10 */
476 i = put_dec(tmp, num) - tmp;
477 }
478
479 /* printing 100 using %2d gives "100", not "00" */
480 if (i > spec.precision)
481 spec.precision = i;
482 /* leading space padding */
483 spec.field_width -= spec.precision;
484 if (!(spec.flags & (ZEROPAD+LEFT))) {
485 while (--spec.field_width >= 0) {
486 if (buf < end)
487 *buf = ' ';
488 ++buf;
489 }
490 }
491 /* sign */
492 if (sign) {
493 if (buf < end)
494 *buf = sign;
495 ++buf;
496 }
497 /* "0x" / "0" prefix */
498 if (need_pfx) {
499 if (buf < end)
500 *buf = '0';
501 ++buf;
502 if (spec.base == 16) {
503 if (buf < end)
504 *buf = ('X' | locase);
505 ++buf;
506 }
507 }
508 /* zero or space padding */
509 if (!(spec.flags & LEFT)) {
510 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
511 while (--spec.field_width >= 0) {
512 if (buf < end)
513 *buf = c;
514 ++buf;
515 }
516 }
517 /* hmm even more zero padding? */
518 while (i <= --spec.precision) {
519 if (buf < end)
520 *buf = '0';
521 ++buf;
522 }
523 /* actual digits of result */
524 while (--i >= 0) {
525 if (buf < end)
526 *buf = tmp[i];
527 ++buf;
528 }
529 /* trailing space padding */
530 while (--spec.field_width >= 0) {
531 if (buf < end)
532 *buf = ' ';
533 ++buf;
534 }
535
536 return buf;
537 }
538
539 static noinline_for_stack
540 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
541 {
542 int len, i;
543
544 if ((unsigned long)s < PAGE_SIZE)
545 s = "(null)";
546
547 len = strnlen(s, spec.precision);
548
549 if (!(spec.flags & LEFT)) {
550 while (len < spec.field_width--) {
551 if (buf < end)
552 *buf = ' ';
553 ++buf;
554 }
555 }
556 for (i = 0; i < len; ++i) {
557 if (buf < end)
558 *buf = *s;
559 ++buf; ++s;
560 }
561 while (len < spec.field_width--) {
562 if (buf < end)
563 *buf = ' ';
564 ++buf;
565 }
566
567 return buf;
568 }
569
570 static noinline_for_stack
571 char *symbol_string(char *buf, char *end, void *ptr,
572 struct printf_spec spec, char ext)
573 {
574 unsigned long value = (unsigned long) ptr;
575 #ifdef CONFIG_KALLSYMS
576 char sym[KSYM_SYMBOL_LEN];
577 if (ext != 'f' && ext != 's')
578 sprint_symbol(sym, value);
579 else
580 kallsyms_lookup(value, NULL, NULL, NULL, sym);
581
582 return string(buf, end, sym, spec);
583 #else
584 spec.field_width = 2 * sizeof(void *);
585 spec.flags |= SPECIAL | SMALL | ZEROPAD;
586 spec.base = 16;
587
588 return number(buf, end, value, spec);
589 #endif
590 }
591
592 static noinline_for_stack
593 char *resource_string(char *buf, char *end, struct resource *res,
594 struct printf_spec spec, const char *fmt)
595 {
596 #ifndef IO_RSRC_PRINTK_SIZE
597 #define IO_RSRC_PRINTK_SIZE 6
598 #endif
599
600 #ifndef MEM_RSRC_PRINTK_SIZE
601 #define MEM_RSRC_PRINTK_SIZE 10
602 #endif
603 static const struct printf_spec io_spec = {
604 .base = 16,
605 .field_width = IO_RSRC_PRINTK_SIZE,
606 .precision = -1,
607 .flags = SPECIAL | SMALL | ZEROPAD,
608 };
609 static const struct printf_spec mem_spec = {
610 .base = 16,
611 .field_width = MEM_RSRC_PRINTK_SIZE,
612 .precision = -1,
613 .flags = SPECIAL | SMALL | ZEROPAD,
614 };
615 static const struct printf_spec bus_spec = {
616 .base = 16,
617 .field_width = 2,
618 .precision = -1,
619 .flags = SMALL | ZEROPAD,
620 };
621 static const struct printf_spec dec_spec = {
622 .base = 10,
623 .precision = -1,
624 .flags = 0,
625 };
626 static const struct printf_spec str_spec = {
627 .field_width = -1,
628 .precision = 10,
629 .flags = LEFT,
630 };
631 static const struct printf_spec flag_spec = {
632 .base = 16,
633 .precision = -1,
634 .flags = SPECIAL | SMALL,
635 };
636
637 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
638 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
639 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
640 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
641 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
642 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
643 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
644 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
645
646 char *p = sym, *pend = sym + sizeof(sym);
647 int decode = (fmt[0] == 'R') ? 1 : 0;
648 const struct printf_spec *specp;
649
650 *p++ = '[';
651 if (res->flags & IORESOURCE_IO) {
652 p = string(p, pend, "io ", str_spec);
653 specp = &io_spec;
654 } else if (res->flags & IORESOURCE_MEM) {
655 p = string(p, pend, "mem ", str_spec);
656 specp = &mem_spec;
657 } else if (res->flags & IORESOURCE_IRQ) {
658 p = string(p, pend, "irq ", str_spec);
659 specp = &dec_spec;
660 } else if (res->flags & IORESOURCE_DMA) {
661 p = string(p, pend, "dma ", str_spec);
662 specp = &dec_spec;
663 } else if (res->flags & IORESOURCE_BUS) {
664 p = string(p, pend, "bus ", str_spec);
665 specp = &bus_spec;
666 } else {
667 p = string(p, pend, "??? ", str_spec);
668 specp = &mem_spec;
669 decode = 0;
670 }
671 p = number(p, pend, res->start, *specp);
672 if (res->start != res->end) {
673 *p++ = '-';
674 p = number(p, pend, res->end, *specp);
675 }
676 if (decode) {
677 if (res->flags & IORESOURCE_MEM_64)
678 p = string(p, pend, " 64bit", str_spec);
679 if (res->flags & IORESOURCE_PREFETCH)
680 p = string(p, pend, " pref", str_spec);
681 if (res->flags & IORESOURCE_WINDOW)
682 p = string(p, pend, " window", str_spec);
683 if (res->flags & IORESOURCE_DISABLED)
684 p = string(p, pend, " disabled", str_spec);
685 } else {
686 p = string(p, pend, " flags ", str_spec);
687 p = number(p, pend, res->flags, flag_spec);
688 }
689 *p++ = ']';
690 *p = '\0';
691
692 return string(buf, end, sym, spec);
693 }
694
695 static noinline_for_stack
696 char *mac_address_string(char *buf, char *end, u8 *addr,
697 struct printf_spec spec, const char *fmt)
698 {
699 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
700 char *p = mac_addr;
701 int i;
702 char separator;
703
704 if (fmt[1] == 'F') { /* FDDI canonical format */
705 separator = '-';
706 } else {
707 separator = ':';
708 }
709
710 for (i = 0; i < 6; i++) {
711 p = pack_hex_byte(p, addr[i]);
712 if (fmt[0] == 'M' && i != 5)
713 *p++ = separator;
714 }
715 *p = '\0';
716
717 return string(buf, end, mac_addr, spec);
718 }
719
720 static noinline_for_stack
721 char *ip4_string(char *p, const u8 *addr, const char *fmt)
722 {
723 int i;
724 bool leading_zeros = (fmt[0] == 'i');
725 int index;
726 int step;
727
728 switch (fmt[2]) {
729 case 'h':
730 #ifdef __BIG_ENDIAN
731 index = 0;
732 step = 1;
733 #else
734 index = 3;
735 step = -1;
736 #endif
737 break;
738 case 'l':
739 index = 3;
740 step = -1;
741 break;
742 case 'n':
743 case 'b':
744 default:
745 index = 0;
746 step = 1;
747 break;
748 }
749 for (i = 0; i < 4; i++) {
750 char temp[3]; /* hold each IP quad in reverse order */
751 int digits = put_dec_trunc(temp, addr[index]) - temp;
752 if (leading_zeros) {
753 if (digits < 3)
754 *p++ = '0';
755 if (digits < 2)
756 *p++ = '0';
757 }
758 /* reverse the digits in the quad */
759 while (digits--)
760 *p++ = temp[digits];
761 if (i < 3)
762 *p++ = '.';
763 index += step;
764 }
765 *p = '\0';
766
767 return p;
768 }
769
770 static noinline_for_stack
771 char *ip6_compressed_string(char *p, const char *addr)
772 {
773 int i, j, range;
774 unsigned char zerolength[8];
775 int longest = 1;
776 int colonpos = -1;
777 u16 word;
778 u8 hi, lo;
779 bool needcolon = false;
780 bool useIPv4;
781 struct in6_addr in6;
782
783 memcpy(&in6, addr, sizeof(struct in6_addr));
784
785 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
786
787 memset(zerolength, 0, sizeof(zerolength));
788
789 if (useIPv4)
790 range = 6;
791 else
792 range = 8;
793
794 /* find position of longest 0 run */
795 for (i = 0; i < range; i++) {
796 for (j = i; j < range; j++) {
797 if (in6.s6_addr16[j] != 0)
798 break;
799 zerolength[i]++;
800 }
801 }
802 for (i = 0; i < range; i++) {
803 if (zerolength[i] > longest) {
804 longest = zerolength[i];
805 colonpos = i;
806 }
807 }
808
809 /* emit address */
810 for (i = 0; i < range; i++) {
811 if (i == colonpos) {
812 if (needcolon || i == 0)
813 *p++ = ':';
814 *p++ = ':';
815 needcolon = false;
816 i += longest - 1;
817 continue;
818 }
819 if (needcolon) {
820 *p++ = ':';
821 needcolon = false;
822 }
823 /* hex u16 without leading 0s */
824 word = ntohs(in6.s6_addr16[i]);
825 hi = word >> 8;
826 lo = word & 0xff;
827 if (hi) {
828 if (hi > 0x0f)
829 p = pack_hex_byte(p, hi);
830 else
831 *p++ = hex_asc_lo(hi);
832 p = pack_hex_byte(p, lo);
833 }
834 else if (lo > 0x0f)
835 p = pack_hex_byte(p, lo);
836 else
837 *p++ = hex_asc_lo(lo);
838 needcolon = true;
839 }
840
841 if (useIPv4) {
842 if (needcolon)
843 *p++ = ':';
844 p = ip4_string(p, &in6.s6_addr[12], "I4");
845 }
846 *p = '\0';
847
848 return p;
849 }
850
851 static noinline_for_stack
852 char *ip6_string(char *p, const char *addr, const char *fmt)
853 {
854 int i;
855
856 for (i = 0; i < 8; i++) {
857 p = pack_hex_byte(p, *addr++);
858 p = pack_hex_byte(p, *addr++);
859 if (fmt[0] == 'I' && i != 7)
860 *p++ = ':';
861 }
862 *p = '\0';
863
864 return p;
865 }
866
867 static noinline_for_stack
868 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
869 struct printf_spec spec, const char *fmt)
870 {
871 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
872
873 if (fmt[0] == 'I' && fmt[2] == 'c')
874 ip6_compressed_string(ip6_addr, addr);
875 else
876 ip6_string(ip6_addr, addr, fmt);
877
878 return string(buf, end, ip6_addr, spec);
879 }
880
881 static noinline_for_stack
882 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
883 struct printf_spec spec, const char *fmt)
884 {
885 char ip4_addr[sizeof("255.255.255.255")];
886
887 ip4_string(ip4_addr, addr, fmt);
888
889 return string(buf, end, ip4_addr, spec);
890 }
891
892 static noinline_for_stack
893 char *uuid_string(char *buf, char *end, const u8 *addr,
894 struct printf_spec spec, const char *fmt)
895 {
896 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
897 char *p = uuid;
898 int i;
899 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
900 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
901 const u8 *index = be;
902 bool uc = false;
903
904 switch (*(++fmt)) {
905 case 'L':
906 uc = true; /* fall-through */
907 case 'l':
908 index = le;
909 break;
910 case 'B':
911 uc = true;
912 break;
913 }
914
915 for (i = 0; i < 16; i++) {
916 p = pack_hex_byte(p, addr[index[i]]);
917 switch (i) {
918 case 3:
919 case 5:
920 case 7:
921 case 9:
922 *p++ = '-';
923 break;
924 }
925 }
926
927 *p = 0;
928
929 if (uc) {
930 p = uuid;
931 do {
932 *p = toupper(*p);
933 } while (*(++p));
934 }
935
936 return string(buf, end, uuid, spec);
937 }
938
939 /*
940 * Show a '%p' thing. A kernel extension is that the '%p' is followed
941 * by an extra set of alphanumeric characters that are extended format
942 * specifiers.
943 *
944 * Right now we handle:
945 *
946 * - 'F' For symbolic function descriptor pointers with offset
947 * - 'f' For simple symbolic function names without offset
948 * - 'S' For symbolic direct pointers with offset
949 * - 's' For symbolic direct pointers without offset
950 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
951 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
952 * - 'M' For a 6-byte MAC address, it prints the address in the
953 * usual colon-separated hex notation
954 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
955 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
956 * with a dash-separated hex notation
957 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
958 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
959 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
960 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
961 * IPv6 omits the colons (01020304...0f)
962 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
963 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
964 * - 'I6c' for IPv6 addresses printed as specified by
965 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
966 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
967 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
968 * Options for %pU are:
969 * b big endian lower case hex (default)
970 * B big endian UPPER case hex
971 * l little endian lower case hex
972 * L little endian UPPER case hex
973 * big endian output byte order is:
974 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
975 * little endian output byte order is:
976 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
977 * - 'V' For a struct va_format which contains a format string * and va_list *,
978 * call vsnprintf(->format, *->va_list).
979 * Implements a "recursive vsnprintf".
980 * Do not use this feature without some mechanism to verify the
981 * correctness of the format string and va_list arguments.
982 *
983 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
984 * function pointers are really function descriptors, which contain a
985 * pointer to the real address.
986 */
987 static noinline_for_stack
988 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
989 struct printf_spec spec)
990 {
991 if (!ptr)
992 return string(buf, end, "(null)", spec);
993
994 switch (*fmt) {
995 case 'F':
996 case 'f':
997 ptr = dereference_function_descriptor(ptr);
998 /* Fallthrough */
999 case 'S':
1000 case 's':
1001 return symbol_string(buf, end, ptr, spec, *fmt);
1002 case 'R':
1003 case 'r':
1004 return resource_string(buf, end, ptr, spec, fmt);
1005 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1006 case 'm': /* Contiguous: 000102030405 */
1007 /* [mM]F (FDDI, bit reversed) */
1008 return mac_address_string(buf, end, ptr, spec, fmt);
1009 case 'I': /* Formatted IP supported
1010 * 4: 1.2.3.4
1011 * 6: 0001:0203:...:0708
1012 * 6c: 1::708 or 1::1.2.3.4
1013 */
1014 case 'i': /* Contiguous:
1015 * 4: 001.002.003.004
1016 * 6: 000102...0f
1017 */
1018 switch (fmt[1]) {
1019 case '6':
1020 return ip6_addr_string(buf, end, ptr, spec, fmt);
1021 case '4':
1022 return ip4_addr_string(buf, end, ptr, spec, fmt);
1023 }
1024 break;
1025 case 'U':
1026 return uuid_string(buf, end, ptr, spec, fmt);
1027 case 'V':
1028 return buf + vsnprintf(buf, end - buf,
1029 ((struct va_format *)ptr)->fmt,
1030 *(((struct va_format *)ptr)->va));
1031 }
1032 spec.flags |= SMALL;
1033 if (spec.field_width == -1) {
1034 spec.field_width = 2*sizeof(void *);
1035 spec.flags |= ZEROPAD;
1036 }
1037 spec.base = 16;
1038
1039 return number(buf, end, (unsigned long) ptr, spec);
1040 }
1041
1042 /*
1043 * Helper function to decode printf style format.
1044 * Each call decode a token from the format and return the
1045 * number of characters read (or likely the delta where it wants
1046 * to go on the next call).
1047 * The decoded token is returned through the parameters
1048 *
1049 * 'h', 'l', or 'L' for integer fields
1050 * 'z' support added 23/7/1999 S.H.
1051 * 'z' changed to 'Z' --davidm 1/25/99
1052 * 't' added for ptrdiff_t
1053 *
1054 * @fmt: the format string
1055 * @type of the token returned
1056 * @flags: various flags such as +, -, # tokens..
1057 * @field_width: overwritten width
1058 * @base: base of the number (octal, hex, ...)
1059 * @precision: precision of a number
1060 * @qualifier: qualifier of a number (long, size_t, ...)
1061 */
1062 static noinline_for_stack
1063 int format_decode(const char *fmt, struct printf_spec *spec)
1064 {
1065 const char *start = fmt;
1066
1067 /* we finished early by reading the field width */
1068 if (spec->type == FORMAT_TYPE_WIDTH) {
1069 if (spec->field_width < 0) {
1070 spec->field_width = -spec->field_width;
1071 spec->flags |= LEFT;
1072 }
1073 spec->type = FORMAT_TYPE_NONE;
1074 goto precision;
1075 }
1076
1077 /* we finished early by reading the precision */
1078 if (spec->type == FORMAT_TYPE_PRECISION) {
1079 if (spec->precision < 0)
1080 spec->precision = 0;
1081
1082 spec->type = FORMAT_TYPE_NONE;
1083 goto qualifier;
1084 }
1085
1086 /* By default */
1087 spec->type = FORMAT_TYPE_NONE;
1088
1089 for (; *fmt ; ++fmt) {
1090 if (*fmt == '%')
1091 break;
1092 }
1093
1094 /* Return the current non-format string */
1095 if (fmt != start || !*fmt)
1096 return fmt - start;
1097
1098 /* Process flags */
1099 spec->flags = 0;
1100
1101 while (1) { /* this also skips first '%' */
1102 bool found = true;
1103
1104 ++fmt;
1105
1106 switch (*fmt) {
1107 case '-': spec->flags |= LEFT; break;
1108 case '+': spec->flags |= PLUS; break;
1109 case ' ': spec->flags |= SPACE; break;
1110 case '#': spec->flags |= SPECIAL; break;
1111 case '0': spec->flags |= ZEROPAD; break;
1112 default: found = false;
1113 }
1114
1115 if (!found)
1116 break;
1117 }
1118
1119 /* get field width */
1120 spec->field_width = -1;
1121
1122 if (isdigit(*fmt))
1123 spec->field_width = skip_atoi(&fmt);
1124 else if (*fmt == '*') {
1125 /* it's the next argument */
1126 spec->type = FORMAT_TYPE_WIDTH;
1127 return ++fmt - start;
1128 }
1129
1130 precision:
1131 /* get the precision */
1132 spec->precision = -1;
1133 if (*fmt == '.') {
1134 ++fmt;
1135 if (isdigit(*fmt)) {
1136 spec->precision = skip_atoi(&fmt);
1137 if (spec->precision < 0)
1138 spec->precision = 0;
1139 } else if (*fmt == '*') {
1140 /* it's the next argument */
1141 spec->type = FORMAT_TYPE_PRECISION;
1142 return ++fmt - start;
1143 }
1144 }
1145
1146 qualifier:
1147 /* get the conversion qualifier */
1148 spec->qualifier = -1;
1149 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1150 TOLOWER(*fmt) == 'z' || *fmt == 't') {
1151 spec->qualifier = *fmt++;
1152 if (unlikely(spec->qualifier == *fmt)) {
1153 if (spec->qualifier == 'l') {
1154 spec->qualifier = 'L';
1155 ++fmt;
1156 } else if (spec->qualifier == 'h') {
1157 spec->qualifier = 'H';
1158 ++fmt;
1159 }
1160 }
1161 }
1162
1163 /* default base */
1164 spec->base = 10;
1165 switch (*fmt) {
1166 case 'c':
1167 spec->type = FORMAT_TYPE_CHAR;
1168 return ++fmt - start;
1169
1170 case 's':
1171 spec->type = FORMAT_TYPE_STR;
1172 return ++fmt - start;
1173
1174 case 'p':
1175 spec->type = FORMAT_TYPE_PTR;
1176 return fmt - start;
1177 /* skip alnum */
1178
1179 case 'n':
1180 spec->type = FORMAT_TYPE_NRCHARS;
1181 return ++fmt - start;
1182
1183 case '%':
1184 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1185 return ++fmt - start;
1186
1187 /* integer number formats - set up the flags and "break" */
1188 case 'o':
1189 spec->base = 8;
1190 break;
1191
1192 case 'x':
1193 spec->flags |= SMALL;
1194
1195 case 'X':
1196 spec->base = 16;
1197 break;
1198
1199 case 'd':
1200 case 'i':
1201 spec->flags |= SIGN;
1202 case 'u':
1203 break;
1204
1205 default:
1206 spec->type = FORMAT_TYPE_INVALID;
1207 return fmt - start;
1208 }
1209
1210 if (spec->qualifier == 'L')
1211 spec->type = FORMAT_TYPE_LONG_LONG;
1212 else if (spec->qualifier == 'l') {
1213 if (spec->flags & SIGN)
1214 spec->type = FORMAT_TYPE_LONG;
1215 else
1216 spec->type = FORMAT_TYPE_ULONG;
1217 } else if (TOLOWER(spec->qualifier) == 'z') {
1218 spec->type = FORMAT_TYPE_SIZE_T;
1219 } else if (spec->qualifier == 't') {
1220 spec->type = FORMAT_TYPE_PTRDIFF;
1221 } else if (spec->qualifier == 'H') {
1222 if (spec->flags & SIGN)
1223 spec->type = FORMAT_TYPE_BYTE;
1224 else
1225 spec->type = FORMAT_TYPE_UBYTE;
1226 } else if (spec->qualifier == 'h') {
1227 if (spec->flags & SIGN)
1228 spec->type = FORMAT_TYPE_SHORT;
1229 else
1230 spec->type = FORMAT_TYPE_USHORT;
1231 } else {
1232 if (spec->flags & SIGN)
1233 spec->type = FORMAT_TYPE_INT;
1234 else
1235 spec->type = FORMAT_TYPE_UINT;
1236 }
1237
1238 return ++fmt - start;
1239 }
1240
1241 /**
1242 * vsnprintf - Format a string and place it in a buffer
1243 * @buf: The buffer to place the result into
1244 * @size: The size of the buffer, including the trailing null space
1245 * @fmt: The format string to use
1246 * @args: Arguments for the format string
1247 *
1248 * This function follows C99 vsnprintf, but has some extensions:
1249 * %pS output the name of a text symbol with offset
1250 * %ps output the name of a text symbol without offset
1251 * %pF output the name of a function pointer with its offset
1252 * %pf output the name of a function pointer without its offset
1253 * %pR output the address range in a struct resource with decoded flags
1254 * %pr output the address range in a struct resource with raw flags
1255 * %pM output a 6-byte MAC address with colons
1256 * %pm output a 6-byte MAC address without colons
1257 * %pI4 print an IPv4 address without leading zeros
1258 * %pi4 print an IPv4 address with leading zeros
1259 * %pI6 print an IPv6 address with colons
1260 * %pi6 print an IPv6 address without colons
1261 * %pI6c print an IPv6 address as specified by
1262 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
1263 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1264 * case.
1265 * %n is ignored
1266 *
1267 * The return value is the number of characters which would
1268 * be generated for the given input, excluding the trailing
1269 * '\0', as per ISO C99. If you want to have the exact
1270 * number of characters written into @buf as return value
1271 * (not including the trailing '\0'), use vscnprintf(). If the
1272 * return is greater than or equal to @size, the resulting
1273 * string is truncated.
1274 *
1275 * Call this function if you are already dealing with a va_list.
1276 * You probably want snprintf() instead.
1277 */
1278 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1279 {
1280 unsigned long long num;
1281 char *str, *end;
1282 struct printf_spec spec = {0};
1283
1284 /* Reject out-of-range values early. Large positive sizes are
1285 used for unknown buffer sizes. */
1286 if (WARN_ON_ONCE((int) size < 0))
1287 return 0;
1288
1289 str = buf;
1290 end = buf + size;
1291
1292 /* Make sure end is always >= buf */
1293 if (end < buf) {
1294 end = ((void *)-1);
1295 size = end - buf;
1296 }
1297
1298 while (*fmt) {
1299 const char *old_fmt = fmt;
1300 int read = format_decode(fmt, &spec);
1301
1302 fmt += read;
1303
1304 switch (spec.type) {
1305 case FORMAT_TYPE_NONE: {
1306 int copy = read;
1307 if (str < end) {
1308 if (copy > end - str)
1309 copy = end - str;
1310 memcpy(str, old_fmt, copy);
1311 }
1312 str += read;
1313 break;
1314 }
1315
1316 case FORMAT_TYPE_WIDTH:
1317 spec.field_width = va_arg(args, int);
1318 break;
1319
1320 case FORMAT_TYPE_PRECISION:
1321 spec.precision = va_arg(args, int);
1322 break;
1323
1324 case FORMAT_TYPE_CHAR: {
1325 char c;
1326
1327 if (!(spec.flags & LEFT)) {
1328 while (--spec.field_width > 0) {
1329 if (str < end)
1330 *str = ' ';
1331 ++str;
1332
1333 }
1334 }
1335 c = (unsigned char) va_arg(args, int);
1336 if (str < end)
1337 *str = c;
1338 ++str;
1339 while (--spec.field_width > 0) {
1340 if (str < end)
1341 *str = ' ';
1342 ++str;
1343 }
1344 break;
1345 }
1346
1347 case FORMAT_TYPE_STR:
1348 str = string(str, end, va_arg(args, char *), spec);
1349 break;
1350
1351 case FORMAT_TYPE_PTR:
1352 str = pointer(fmt+1, str, end, va_arg(args, void *),
1353 spec);
1354 while (isalnum(*fmt))
1355 fmt++;
1356 break;
1357
1358 case FORMAT_TYPE_PERCENT_CHAR:
1359 if (str < end)
1360 *str = '%';
1361 ++str;
1362 break;
1363
1364 case FORMAT_TYPE_INVALID:
1365 if (str < end)
1366 *str = '%';
1367 ++str;
1368 break;
1369
1370 case FORMAT_TYPE_NRCHARS: {
1371 u8 qualifier = spec.qualifier;
1372
1373 if (qualifier == 'l') {
1374 long *ip = va_arg(args, long *);
1375 *ip = (str - buf);
1376 } else if (TOLOWER(qualifier) == 'z') {
1377 size_t *ip = va_arg(args, size_t *);
1378 *ip = (str - buf);
1379 } else {
1380 int *ip = va_arg(args, int *);
1381 *ip = (str - buf);
1382 }
1383 break;
1384 }
1385
1386 default:
1387 switch (spec.type) {
1388 case FORMAT_TYPE_LONG_LONG:
1389 num = va_arg(args, long long);
1390 break;
1391 case FORMAT_TYPE_ULONG:
1392 num = va_arg(args, unsigned long);
1393 break;
1394 case FORMAT_TYPE_LONG:
1395 num = va_arg(args, long);
1396 break;
1397 case FORMAT_TYPE_SIZE_T:
1398 num = va_arg(args, size_t);
1399 break;
1400 case FORMAT_TYPE_PTRDIFF:
1401 num = va_arg(args, ptrdiff_t);
1402 break;
1403 case FORMAT_TYPE_UBYTE:
1404 num = (unsigned char) va_arg(args, int);
1405 break;
1406 case FORMAT_TYPE_BYTE:
1407 num = (signed char) va_arg(args, int);
1408 break;
1409 case FORMAT_TYPE_USHORT:
1410 num = (unsigned short) va_arg(args, int);
1411 break;
1412 case FORMAT_TYPE_SHORT:
1413 num = (short) va_arg(args, int);
1414 break;
1415 case FORMAT_TYPE_INT:
1416 num = (int) va_arg(args, int);
1417 break;
1418 default:
1419 num = va_arg(args, unsigned int);
1420 }
1421
1422 str = number(str, end, num, spec);
1423 }
1424 }
1425
1426 if (size > 0) {
1427 if (str < end)
1428 *str = '\0';
1429 else
1430 end[-1] = '\0';
1431 }
1432
1433 /* the trailing null byte doesn't count towards the total */
1434 return str-buf;
1435
1436 }
1437 EXPORT_SYMBOL(vsnprintf);
1438
1439 /**
1440 * vscnprintf - Format a string and place it in a buffer
1441 * @buf: The buffer to place the result into
1442 * @size: The size of the buffer, including the trailing null space
1443 * @fmt: The format string to use
1444 * @args: Arguments for the format string
1445 *
1446 * The return value is the number of characters which have been written into
1447 * the @buf not including the trailing '\0'. If @size is <= 0 the function
1448 * returns 0.
1449 *
1450 * Call this function if you are already dealing with a va_list.
1451 * You probably want scnprintf() instead.
1452 *
1453 * See the vsnprintf() documentation for format string extensions over C99.
1454 */
1455 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1456 {
1457 int i;
1458
1459 i = vsnprintf(buf, size, fmt, args);
1460
1461 return (i >= size) ? (size - 1) : i;
1462 }
1463 EXPORT_SYMBOL(vscnprintf);
1464
1465 /**
1466 * snprintf - Format a string and place it in a buffer
1467 * @buf: The buffer to place the result into
1468 * @size: The size of the buffer, including the trailing null space
1469 * @fmt: The format string to use
1470 * @...: Arguments for the format string
1471 *
1472 * The return value is the number of characters which would be
1473 * generated for the given input, excluding the trailing null,
1474 * as per ISO C99. If the return is greater than or equal to
1475 * @size, the resulting string is truncated.
1476 *
1477 * See the vsnprintf() documentation for format string extensions over C99.
1478 */
1479 int snprintf(char *buf, size_t size, const char *fmt, ...)
1480 {
1481 va_list args;
1482 int i;
1483
1484 va_start(args, fmt);
1485 i = vsnprintf(buf, size, fmt, args);
1486 va_end(args);
1487
1488 return i;
1489 }
1490 EXPORT_SYMBOL(snprintf);
1491
1492 /**
1493 * scnprintf - Format a string and place it in a buffer
1494 * @buf: The buffer to place the result into
1495 * @size: The size of the buffer, including the trailing null space
1496 * @fmt: The format string to use
1497 * @...: Arguments for the format string
1498 *
1499 * The return value is the number of characters written into @buf not including
1500 * the trailing '\0'. If @size is <= 0 the function returns 0.
1501 */
1502
1503 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1504 {
1505 va_list args;
1506 int i;
1507
1508 va_start(args, fmt);
1509 i = vsnprintf(buf, size, fmt, args);
1510 va_end(args);
1511
1512 return (i >= size) ? (size - 1) : i;
1513 }
1514 EXPORT_SYMBOL(scnprintf);
1515
1516 /**
1517 * vsprintf - Format a string and place it in a buffer
1518 * @buf: The buffer to place the result into
1519 * @fmt: The format string to use
1520 * @args: Arguments for the format string
1521 *
1522 * The function returns the number of characters written
1523 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1524 * buffer overflows.
1525 *
1526 * Call this function if you are already dealing with a va_list.
1527 * You probably want sprintf() instead.
1528 *
1529 * See the vsnprintf() documentation for format string extensions over C99.
1530 */
1531 int vsprintf(char *buf, const char *fmt, va_list args)
1532 {
1533 return vsnprintf(buf, INT_MAX, fmt, args);
1534 }
1535 EXPORT_SYMBOL(vsprintf);
1536
1537 /**
1538 * sprintf - Format a string and place it in a buffer
1539 * @buf: The buffer to place the result into
1540 * @fmt: The format string to use
1541 * @...: Arguments for the format string
1542 *
1543 * The function returns the number of characters written
1544 * into @buf. Use snprintf() or scnprintf() in order to avoid
1545 * buffer overflows.
1546 *
1547 * See the vsnprintf() documentation for format string extensions over C99.
1548 */
1549 int sprintf(char *buf, const char *fmt, ...)
1550 {
1551 va_list args;
1552 int i;
1553
1554 va_start(args, fmt);
1555 i = vsnprintf(buf, INT_MAX, fmt, args);
1556 va_end(args);
1557
1558 return i;
1559 }
1560 EXPORT_SYMBOL(sprintf);
1561
1562 #ifdef CONFIG_BINARY_PRINTF
1563 /*
1564 * bprintf service:
1565 * vbin_printf() - VA arguments to binary data
1566 * bstr_printf() - Binary data to text string
1567 */
1568
1569 /**
1570 * vbin_printf - Parse a format string and place args' binary value in a buffer
1571 * @bin_buf: The buffer to place args' binary value
1572 * @size: The size of the buffer(by words(32bits), not characters)
1573 * @fmt: The format string to use
1574 * @args: Arguments for the format string
1575 *
1576 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1577 * is skiped.
1578 *
1579 * The return value is the number of words(32bits) which would be generated for
1580 * the given input.
1581 *
1582 * NOTE:
1583 * If the return value is greater than @size, the resulting bin_buf is NOT
1584 * valid for bstr_printf().
1585 */
1586 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1587 {
1588 struct printf_spec spec = {0};
1589 char *str, *end;
1590
1591 str = (char *)bin_buf;
1592 end = (char *)(bin_buf + size);
1593
1594 #define save_arg(type) \
1595 do { \
1596 if (sizeof(type) == 8) { \
1597 unsigned long long value; \
1598 str = PTR_ALIGN(str, sizeof(u32)); \
1599 value = va_arg(args, unsigned long long); \
1600 if (str + sizeof(type) <= end) { \
1601 *(u32 *)str = *(u32 *)&value; \
1602 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1603 } \
1604 } else { \
1605 unsigned long value; \
1606 str = PTR_ALIGN(str, sizeof(type)); \
1607 value = va_arg(args, int); \
1608 if (str + sizeof(type) <= end) \
1609 *(typeof(type) *)str = (type)value; \
1610 } \
1611 str += sizeof(type); \
1612 } while (0)
1613
1614 while (*fmt) {
1615 int read = format_decode(fmt, &spec);
1616
1617 fmt += read;
1618
1619 switch (spec.type) {
1620 case FORMAT_TYPE_NONE:
1621 case FORMAT_TYPE_INVALID:
1622 case FORMAT_TYPE_PERCENT_CHAR:
1623 break;
1624
1625 case FORMAT_TYPE_WIDTH:
1626 case FORMAT_TYPE_PRECISION:
1627 save_arg(int);
1628 break;
1629
1630 case FORMAT_TYPE_CHAR:
1631 save_arg(char);
1632 break;
1633
1634 case FORMAT_TYPE_STR: {
1635 const char *save_str = va_arg(args, char *);
1636 size_t len;
1637
1638 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1639 || (unsigned long)save_str < PAGE_SIZE)
1640 save_str = "(null)";
1641 len = strlen(save_str) + 1;
1642 if (str + len < end)
1643 memcpy(str, save_str, len);
1644 str += len;
1645 break;
1646 }
1647
1648 case FORMAT_TYPE_PTR:
1649 save_arg(void *);
1650 /* skip all alphanumeric pointer suffixes */
1651 while (isalnum(*fmt))
1652 fmt++;
1653 break;
1654
1655 case FORMAT_TYPE_NRCHARS: {
1656 /* skip %n 's argument */
1657 u8 qualifier = spec.qualifier;
1658 void *skip_arg;
1659 if (qualifier == 'l')
1660 skip_arg = va_arg(args, long *);
1661 else if (TOLOWER(qualifier) == 'z')
1662 skip_arg = va_arg(args, size_t *);
1663 else
1664 skip_arg = va_arg(args, int *);
1665 break;
1666 }
1667
1668 default:
1669 switch (spec.type) {
1670
1671 case FORMAT_TYPE_LONG_LONG:
1672 save_arg(long long);
1673 break;
1674 case FORMAT_TYPE_ULONG:
1675 case FORMAT_TYPE_LONG:
1676 save_arg(unsigned long);
1677 break;
1678 case FORMAT_TYPE_SIZE_T:
1679 save_arg(size_t);
1680 break;
1681 case FORMAT_TYPE_PTRDIFF:
1682 save_arg(ptrdiff_t);
1683 break;
1684 case FORMAT_TYPE_UBYTE:
1685 case FORMAT_TYPE_BYTE:
1686 save_arg(char);
1687 break;
1688 case FORMAT_TYPE_USHORT:
1689 case FORMAT_TYPE_SHORT:
1690 save_arg(short);
1691 break;
1692 default:
1693 save_arg(int);
1694 }
1695 }
1696 }
1697
1698 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1699 #undef save_arg
1700 }
1701 EXPORT_SYMBOL_GPL(vbin_printf);
1702
1703 /**
1704 * bstr_printf - Format a string from binary arguments and place it in a buffer
1705 * @buf: The buffer to place the result into
1706 * @size: The size of the buffer, including the trailing null space
1707 * @fmt: The format string to use
1708 * @bin_buf: Binary arguments for the format string
1709 *
1710 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1711 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1712 * a binary buffer that generated by vbin_printf.
1713 *
1714 * The format follows C99 vsnprintf, but has some extensions:
1715 * see vsnprintf comment for details.
1716 *
1717 * The return value is the number of characters which would
1718 * be generated for the given input, excluding the trailing
1719 * '\0', as per ISO C99. If you want to have the exact
1720 * number of characters written into @buf as return value
1721 * (not including the trailing '\0'), use vscnprintf(). If the
1722 * return is greater than or equal to @size, the resulting
1723 * string is truncated.
1724 */
1725 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1726 {
1727 struct printf_spec spec = {0};
1728 char *str, *end;
1729 const char *args = (const char *)bin_buf;
1730
1731 if (WARN_ON_ONCE((int) size < 0))
1732 return 0;
1733
1734 str = buf;
1735 end = buf + size;
1736
1737 #define get_arg(type) \
1738 ({ \
1739 typeof(type) value; \
1740 if (sizeof(type) == 8) { \
1741 args = PTR_ALIGN(args, sizeof(u32)); \
1742 *(u32 *)&value = *(u32 *)args; \
1743 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1744 } else { \
1745 args = PTR_ALIGN(args, sizeof(type)); \
1746 value = *(typeof(type) *)args; \
1747 } \
1748 args += sizeof(type); \
1749 value; \
1750 })
1751
1752 /* Make sure end is always >= buf */
1753 if (end < buf) {
1754 end = ((void *)-1);
1755 size = end - buf;
1756 }
1757
1758 while (*fmt) {
1759 const char *old_fmt = fmt;
1760 int read = format_decode(fmt, &spec);
1761
1762 fmt += read;
1763
1764 switch (spec.type) {
1765 case FORMAT_TYPE_NONE: {
1766 int copy = read;
1767 if (str < end) {
1768 if (copy > end - str)
1769 copy = end - str;
1770 memcpy(str, old_fmt, copy);
1771 }
1772 str += read;
1773 break;
1774 }
1775
1776 case FORMAT_TYPE_WIDTH:
1777 spec.field_width = get_arg(int);
1778 break;
1779
1780 case FORMAT_TYPE_PRECISION:
1781 spec.precision = get_arg(int);
1782 break;
1783
1784 case FORMAT_TYPE_CHAR: {
1785 char c;
1786
1787 if (!(spec.flags & LEFT)) {
1788 while (--spec.field_width > 0) {
1789 if (str < end)
1790 *str = ' ';
1791 ++str;
1792 }
1793 }
1794 c = (unsigned char) get_arg(char);
1795 if (str < end)
1796 *str = c;
1797 ++str;
1798 while (--spec.field_width > 0) {
1799 if (str < end)
1800 *str = ' ';
1801 ++str;
1802 }
1803 break;
1804 }
1805
1806 case FORMAT_TYPE_STR: {
1807 const char *str_arg = args;
1808 args += strlen(str_arg) + 1;
1809 str = string(str, end, (char *)str_arg, spec);
1810 break;
1811 }
1812
1813 case FORMAT_TYPE_PTR:
1814 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1815 while (isalnum(*fmt))
1816 fmt++;
1817 break;
1818
1819 case FORMAT_TYPE_PERCENT_CHAR:
1820 case FORMAT_TYPE_INVALID:
1821 if (str < end)
1822 *str = '%';
1823 ++str;
1824 break;
1825
1826 case FORMAT_TYPE_NRCHARS:
1827 /* skip */
1828 break;
1829
1830 default: {
1831 unsigned long long num;
1832
1833 switch (spec.type) {
1834
1835 case FORMAT_TYPE_LONG_LONG:
1836 num = get_arg(long long);
1837 break;
1838 case FORMAT_TYPE_ULONG:
1839 case FORMAT_TYPE_LONG:
1840 num = get_arg(unsigned long);
1841 break;
1842 case FORMAT_TYPE_SIZE_T:
1843 num = get_arg(size_t);
1844 break;
1845 case FORMAT_TYPE_PTRDIFF:
1846 num = get_arg(ptrdiff_t);
1847 break;
1848 case FORMAT_TYPE_UBYTE:
1849 num = get_arg(unsigned char);
1850 break;
1851 case FORMAT_TYPE_BYTE:
1852 num = get_arg(signed char);
1853 break;
1854 case FORMAT_TYPE_USHORT:
1855 num = get_arg(unsigned short);
1856 break;
1857 case FORMAT_TYPE_SHORT:
1858 num = get_arg(short);
1859 break;
1860 case FORMAT_TYPE_UINT:
1861 num = get_arg(unsigned int);
1862 break;
1863 default:
1864 num = get_arg(int);
1865 }
1866
1867 str = number(str, end, num, spec);
1868 } /* default: */
1869 } /* switch(spec.type) */
1870 } /* while(*fmt) */
1871
1872 if (size > 0) {
1873 if (str < end)
1874 *str = '\0';
1875 else
1876 end[-1] = '\0';
1877 }
1878
1879 #undef get_arg
1880
1881 /* the trailing null byte doesn't count towards the total */
1882 return str - buf;
1883 }
1884 EXPORT_SYMBOL_GPL(bstr_printf);
1885
1886 /**
1887 * bprintf - Parse a format string and place args' binary value in a buffer
1888 * @bin_buf: The buffer to place args' binary value
1889 * @size: The size of the buffer(by words(32bits), not characters)
1890 * @fmt: The format string to use
1891 * @...: Arguments for the format string
1892 *
1893 * The function returns the number of words(u32) written
1894 * into @bin_buf.
1895 */
1896 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1897 {
1898 va_list args;
1899 int ret;
1900
1901 va_start(args, fmt);
1902 ret = vbin_printf(bin_buf, size, fmt, args);
1903 va_end(args);
1904
1905 return ret;
1906 }
1907 EXPORT_SYMBOL_GPL(bprintf);
1908
1909 #endif /* CONFIG_BINARY_PRINTF */
1910
1911 /**
1912 * vsscanf - Unformat a buffer into a list of arguments
1913 * @buf: input buffer
1914 * @fmt: format of buffer
1915 * @args: arguments
1916 */
1917 int vsscanf(const char *buf, const char *fmt, va_list args)
1918 {
1919 const char *str = buf;
1920 char *next;
1921 char digit;
1922 int num = 0;
1923 u8 qualifier;
1924 u8 base;
1925 s16 field_width;
1926 bool is_sign;
1927
1928 while (*fmt && *str) {
1929 /* skip any white space in format */
1930 /* white space in format matchs any amount of
1931 * white space, including none, in the input.
1932 */
1933 if (isspace(*fmt)) {
1934 fmt = skip_spaces(++fmt);
1935 str = skip_spaces(str);
1936 }
1937
1938 /* anything that is not a conversion must match exactly */
1939 if (*fmt != '%' && *fmt) {
1940 if (*fmt++ != *str++)
1941 break;
1942 continue;
1943 }
1944
1945 if (!*fmt)
1946 break;
1947 ++fmt;
1948
1949 /* skip this conversion.
1950 * advance both strings to next white space
1951 */
1952 if (*fmt == '*') {
1953 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1954 fmt++;
1955 while (!isspace(*str) && *str)
1956 str++;
1957 continue;
1958 }
1959
1960 /* get field width */
1961 field_width = -1;
1962 if (isdigit(*fmt))
1963 field_width = skip_atoi(&fmt);
1964
1965 /* get conversion qualifier */
1966 qualifier = -1;
1967 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1968 TOLOWER(*fmt) == 'z') {
1969 qualifier = *fmt++;
1970 if (unlikely(qualifier == *fmt)) {
1971 if (qualifier == 'h') {
1972 qualifier = 'H';
1973 fmt++;
1974 } else if (qualifier == 'l') {
1975 qualifier = 'L';
1976 fmt++;
1977 }
1978 }
1979 }
1980
1981 if (!*fmt || !*str)
1982 break;
1983
1984 base = 10;
1985 is_sign = 0;
1986
1987 switch (*fmt++) {
1988 case 'c':
1989 {
1990 char *s = (char *)va_arg(args, char*);
1991 if (field_width == -1)
1992 field_width = 1;
1993 do {
1994 *s++ = *str++;
1995 } while (--field_width > 0 && *str);
1996 num++;
1997 }
1998 continue;
1999 case 's':
2000 {
2001 char *s = (char *)va_arg(args, char *);
2002 if (field_width == -1)
2003 field_width = SHRT_MAX;
2004 /* first, skip leading white space in buffer */
2005 str = skip_spaces(str);
2006
2007 /* now copy until next white space */
2008 while (*str && !isspace(*str) && field_width--)
2009 *s++ = *str++;
2010 *s = '\0';
2011 num++;
2012 }
2013 continue;
2014 case 'n':
2015 /* return number of characters read so far */
2016 {
2017 int *i = (int *)va_arg(args, int*);
2018 *i = str - buf;
2019 }
2020 continue;
2021 case 'o':
2022 base = 8;
2023 break;
2024 case 'x':
2025 case 'X':
2026 base = 16;
2027 break;
2028 case 'i':
2029 base = 0;
2030 case 'd':
2031 is_sign = 1;
2032 case 'u':
2033 break;
2034 case '%':
2035 /* looking for '%' in str */
2036 if (*str++ != '%')
2037 return num;
2038 continue;
2039 default:
2040 /* invalid format; stop here */
2041 return num;
2042 }
2043
2044 /* have some sort of integer conversion.
2045 * first, skip white space in buffer.
2046 */
2047 str = skip_spaces(str);
2048
2049 digit = *str;
2050 if (is_sign && digit == '-')
2051 digit = *(str + 1);
2052
2053 if (!digit
2054 || (base == 16 && !isxdigit(digit))
2055 || (base == 10 && !isdigit(digit))
2056 || (base == 8 && (!isdigit(digit) || digit > '7'))
2057 || (base == 0 && !isdigit(digit)))
2058 break;
2059
2060 switch (qualifier) {
2061 case 'H': /* that's 'hh' in format */
2062 if (is_sign) {
2063 signed char *s = (signed char *)va_arg(args, signed char *);
2064 *s = (signed char)simple_strtol(str, &next, base);
2065 } else {
2066 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
2067 *s = (unsigned char)simple_strtoul(str, &next, base);
2068 }
2069 break;
2070 case 'h':
2071 if (is_sign) {
2072 short *s = (short *)va_arg(args, short *);
2073 *s = (short)simple_strtol(str, &next, base);
2074 } else {
2075 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
2076 *s = (unsigned short)simple_strtoul(str, &next, base);
2077 }
2078 break;
2079 case 'l':
2080 if (is_sign) {
2081 long *l = (long *)va_arg(args, long *);
2082 *l = simple_strtol(str, &next, base);
2083 } else {
2084 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2085 *l = simple_strtoul(str, &next, base);
2086 }
2087 break;
2088 case 'L':
2089 if (is_sign) {
2090 long long *l = (long long *)va_arg(args, long long *);
2091 *l = simple_strtoll(str, &next, base);
2092 } else {
2093 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2094 *l = simple_strtoull(str, &next, base);
2095 }
2096 break;
2097 case 'Z':
2098 case 'z':
2099 {
2100 size_t *s = (size_t *)va_arg(args, size_t *);
2101 *s = (size_t)simple_strtoul(str, &next, base);
2102 }
2103 break;
2104 default:
2105 if (is_sign) {
2106 int *i = (int *)va_arg(args, int *);
2107 *i = (int)simple_strtol(str, &next, base);
2108 } else {
2109 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2110 *i = (unsigned int)simple_strtoul(str, &next, base);
2111 }
2112 break;
2113 }
2114 num++;
2115
2116 if (!next)
2117 break;
2118 str = next;
2119 }
2120
2121 /*
2122 * Now we've come all the way through so either the input string or the
2123 * format ended. In the former case, there can be a %n at the current
2124 * position in the format that needs to be filled.
2125 */
2126 if (*fmt == '%' && *(fmt + 1) == 'n') {
2127 int *p = (int *)va_arg(args, int *);
2128 *p = str - buf;
2129 }
2130
2131 return num;
2132 }
2133 EXPORT_SYMBOL(vsscanf);
2134
2135 /**
2136 * sscanf - Unformat a buffer into a list of arguments
2137 * @buf: input buffer
2138 * @fmt: formatting of buffer
2139 * @...: resulting arguments
2140 */
2141 int sscanf(const char *buf, const char *fmt, ...)
2142 {
2143 va_list args;
2144 int i;
2145
2146 va_start(args, fmt);
2147 i = vsscanf(buf, fmt, args);
2148 va_end(args);
2149
2150 return i;
2151 }
2152 EXPORT_SYMBOL(sscanf);
Linus' kernel tree