TTY: include termios.h in tty_driver.h
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / lib / vsprintf.c
blobc150d3dafff4a4152f085ff1ae33ae0f122f25f6
1 /*
2 * linux/lib/vsprintf.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8 /*
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
16 * - scnprintf and vscnprintf
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>
30 #include <asm/page.h> /* for PAGE_SIZE */
31 #include <asm/div64.h>
32 #include <asm/sections.h> /* for dereference_function_descriptor() */
34 /* Works only for digits and letters, but small and fast */
35 #define TOLOWER(x) ((x) | 0x20)
37 static unsigned int simple_guess_base(const char *cp)
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;
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
55 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
57 unsigned long long result = 0;
59 if (!base)
60 base = simple_guess_base(cp);
62 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
63 cp += 2;
65 while (isxdigit(*cp)) {
66 unsigned int value;
68 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
69 if (value >= base)
70 break;
71 result = result * base + value;
72 cp++;
74 if (endp)
75 *endp = (char *)cp;
77 return result;
79 EXPORT_SYMBOL(simple_strtoull);
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
87 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
89 return simple_strtoull(cp, endp, base);
91 EXPORT_SYMBOL(simple_strtoul);
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
99 long simple_strtol(const char *cp, char **endp, unsigned int base)
101 if (*cp == '-')
102 return -simple_strtoul(cp + 1, endp, base);
104 return simple_strtoul(cp, endp, base);
106 EXPORT_SYMBOL(simple_strtol);
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
114 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
116 if (*cp == '-')
117 return -simple_strtoull(cp + 1, endp, base);
119 return simple_strtoull(cp, endp, base);
121 EXPORT_SYMBOL(simple_strtoll);
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
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:
135 * echo 1024 > /sys/module/e1000/parameters/copybreak
137 * echo will append a newline to the tail.
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.
142 * simple_strtoul just ignores the successive invalid characters and
143 * return the converted value of prefix part of the string.
145 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
147 char *tail;
148 unsigned long val;
150 *res = 0;
151 if (!*cp)
152 return -EINVAL;
154 val = simple_strtoul(cp, &tail, base);
155 if (tail == cp)
156 return -EINVAL;
158 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
159 *res = val;
160 return 0;
163 return -EINVAL;
165 EXPORT_SYMBOL(strict_strtoul);
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
173 * strict_strtol is similiar to strict_strtoul, but it allows the first
174 * character of a string is '-'.
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.
179 int strict_strtol(const char *cp, unsigned int base, long *res)
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);
190 return ret;
192 EXPORT_SYMBOL(strict_strtol);
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
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:
206 * echo 1024 > /sys/module/e1000/parameters/copybreak
208 * echo will append a newline to the tail of the string.
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.
213 * simple_strtoull just ignores the successive invalid characters and
214 * return the converted value of prefix part of the string.
216 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
218 char *tail;
219 unsigned long long val;
221 *res = 0;
222 if (!*cp)
223 return -EINVAL;
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;
233 return -EINVAL;
235 EXPORT_SYMBOL(strict_strtoull);
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
243 * strict_strtoll is similiar to strict_strtoull, but it allows the first
244 * character of a string is '-'.
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.
249 int strict_strtoll(const char *cp, unsigned int base, long long *res)
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);
260 return ret;
262 EXPORT_SYMBOL(strict_strtoll);
264 static noinline_for_stack
265 int skip_atoi(const char **s)
267 int i = 0;
269 while (isdigit(**s))
270 i = i*10 + *((*s)++) - '0';
272 return i;
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). */
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)
288 unsigned d3, d2, d1, d0;
289 d1 = (q>>4) & 0xf;
290 d2 = (q>>8) & 0xf;
291 d3 = (q>>12);
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 */
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 */
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 */
320 return buf;
322 /* Same with if's removed. Always emits five digits */
323 static noinline_for_stack
324 char *put_dec_full(char *buf, unsigned q)
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);
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)
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';
351 d2 = q + 2*d2;
352 q = (d2 * 0xd) >> 7;
353 d2 = d2 - 10*q;
354 *buf++ = d2 + '0';
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';
363 return buf;
365 /* No inlining helps gcc to use registers better */
366 static noinline_for_stack
367 char *put_dec(char *buf, unsigned long long num)
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);
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" */
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
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 */
418 static noinline_for_stack
419 char *number(char *buf, char *end, unsigned long long num,
420 struct printf_spec spec)
422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
425 char tmp[66];
426 char sign;
427 char locase;
428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
429 int i;
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--;
450 if (need_pfx) {
451 spec.field_width--;
452 if (spec.base == 16)
453 spec.field_width--;
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);
465 else if (spec.base != 10) { /* 8 or 16 */
466 int mask = spec.base - 1;
467 int shift = 3;
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;
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;
491 /* sign */
492 if (sign) {
493 if (buf < end)
494 *buf = sign;
495 ++buf;
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;
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;
517 /* hmm even more zero padding? */
518 while (i <= --spec.precision) {
519 if (buf < end)
520 *buf = '0';
521 ++buf;
523 /* actual digits of result */
524 while (--i >= 0) {
525 if (buf < end)
526 *buf = tmp[i];
527 ++buf;
529 /* trailing space padding */
530 while (--spec.field_width >= 0) {
531 if (buf < end)
532 *buf = ' ';
533 ++buf;
536 return buf;
539 static noinline_for_stack
540 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
542 int len, i;
544 if ((unsigned long)s < PAGE_SIZE)
545 s = "(null)";
547 len = strnlen(s, spec.precision);
549 if (!(spec.flags & LEFT)) {
550 while (len < spec.field_width--) {
551 if (buf < end)
552 *buf = ' ';
553 ++buf;
556 for (i = 0; i < len; ++i) {
557 if (buf < end)
558 *buf = *s;
559 ++buf; ++s;
561 while (len < spec.field_width--) {
562 if (buf < end)
563 *buf = ' ';
564 ++buf;
567 return buf;
570 static noinline_for_stack
571 char *symbol_string(char *buf, char *end, void *ptr,
572 struct printf_spec spec, char ext)
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);
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;
588 return number(buf, end, value, spec);
589 #endif
592 static noinline_for_stack
593 char *resource_string(char *buf, char *end, struct resource *res,
594 struct printf_spec spec, const char *fmt)
596 #ifndef IO_RSRC_PRINTK_SIZE
597 #define IO_RSRC_PRINTK_SIZE 6
598 #endif
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,
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,
615 static const struct printf_spec bus_spec = {
616 .base = 16,
617 .field_width = 2,
618 .precision = -1,
619 .flags = SMALL | ZEROPAD,
621 static const struct printf_spec dec_spec = {
622 .base = 10,
623 .precision = -1,
624 .flags = 0,
626 static const struct printf_spec str_spec = {
627 .field_width = -1,
628 .precision = 10,
629 .flags = LEFT,
631 static const struct printf_spec flag_spec = {
632 .base = 16,
633 .precision = -1,
634 .flags = SPECIAL | SMALL,
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)];
646 char *p = sym, *pend = sym + sizeof(sym);
647 int decode = (fmt[0] == 'R') ? 1 : 0;
648 const struct printf_spec *specp;
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;
671 p = number(p, pend, res->start, *specp);
672 if (res->start != res->end) {
673 *p++ = '-';
674 p = number(p, pend, res->end, *specp);
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);
689 *p++ = ']';
690 *p = '\0';
692 return string(buf, end, sym, spec);
695 static noinline_for_stack
696 char *mac_address_string(char *buf, char *end, u8 *addr,
697 struct printf_spec spec, const char *fmt)
699 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
700 char *p = mac_addr;
701 int i;
702 char separator;
704 if (fmt[1] == 'F') { /* FDDI canonical format */
705 separator = '-';
706 } else {
707 separator = ':';
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;
715 *p = '\0';
717 return string(buf, end, mac_addr, spec);
720 static noinline_for_stack
721 char *ip4_string(char *p, const u8 *addr, const char *fmt)
723 int i;
724 bool leading_zeros = (fmt[0] == 'i');
725 int index;
726 int step;
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;
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';
758 /* reverse the digits in the quad */
759 while (digits--)
760 *p++ = temp[digits];
761 if (i < 3)
762 *p++ = '.';
763 index += step;
765 *p = '\0';
767 return p;
770 static noinline_for_stack
771 char *ip6_compressed_string(char *p, const char *addr)
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;
783 memcpy(&in6, addr, sizeof(struct in6_addr));
785 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
787 memset(zerolength, 0, sizeof(zerolength));
789 if (useIPv4)
790 range = 6;
791 else
792 range = 8;
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]++;
802 for (i = 0; i < range; i++) {
803 if (zerolength[i] > longest) {
804 longest = zerolength[i];
805 colonpos = i;
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;
819 if (needcolon) {
820 *p++ = ':';
821 needcolon = false;
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);
834 else if (lo > 0x0f)
835 p = pack_hex_byte(p, lo);
836 else
837 *p++ = hex_asc_lo(lo);
838 needcolon = true;
841 if (useIPv4) {
842 if (needcolon)
843 *p++ = ':';
844 p = ip4_string(p, &in6.s6_addr[12], "I4");
846 *p = '\0';
848 return p;
851 static noinline_for_stack
852 char *ip6_string(char *p, const char *addr, const char *fmt)
854 int i;
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++ = ':';
862 *p = '\0';
864 return p;
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)
871 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
873 if (fmt[0] == 'I' && fmt[2] == 'c')
874 ip6_compressed_string(ip6_addr, addr);
875 else
876 ip6_string(ip6_addr, addr, fmt);
878 return string(buf, end, ip6_addr, spec);
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)
885 char ip4_addr[sizeof("255.255.255.255")];
887 ip4_string(ip4_addr, addr, fmt);
889 return string(buf, end, ip4_addr, spec);
892 static noinline_for_stack
893 char *uuid_string(char *buf, char *end, const u8 *addr,
894 struct printf_spec spec, const char *fmt)
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;
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;
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;
927 *p = 0;
929 if (uc) {
930 p = uuid;
931 do {
932 *p = toupper(*p);
933 } while (*(++p));
936 return string(buf, end, uuid, spec);
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.
944 * Right now we handle:
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.
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.
987 static noinline_for_stack
988 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
989 struct printf_spec spec)
991 if (!ptr) {
993 * Print (null) with the same width as a pointer so it makes
994 * tabular output look nice.
996 if (spec.field_width == -1)
997 spec.field_width = 2 * sizeof(void *);
998 return string(buf, end, "(null)", spec);
1001 switch (*fmt) {
1002 case 'F':
1003 case 'f':
1004 ptr = dereference_function_descriptor(ptr);
1005 /* Fallthrough */
1006 case 'S':
1007 case 's':
1008 return symbol_string(buf, end, ptr, spec, *fmt);
1009 case 'R':
1010 case 'r':
1011 return resource_string(buf, end, ptr, spec, fmt);
1012 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1013 case 'm': /* Contiguous: 000102030405 */
1014 /* [mM]F (FDDI, bit reversed) */
1015 return mac_address_string(buf, end, ptr, spec, fmt);
1016 case 'I': /* Formatted IP supported
1017 * 4: 1.2.3.4
1018 * 6: 0001:0203:...:0708
1019 * 6c: 1::708 or 1::1.2.3.4
1021 case 'i': /* Contiguous:
1022 * 4: 001.002.003.004
1023 * 6: 000102...0f
1025 switch (fmt[1]) {
1026 case '6':
1027 return ip6_addr_string(buf, end, ptr, spec, fmt);
1028 case '4':
1029 return ip4_addr_string(buf, end, ptr, spec, fmt);
1031 break;
1032 case 'U':
1033 return uuid_string(buf, end, ptr, spec, fmt);
1034 case 'V':
1035 return buf + vsnprintf(buf, end - buf,
1036 ((struct va_format *)ptr)->fmt,
1037 *(((struct va_format *)ptr)->va));
1039 spec.flags |= SMALL;
1040 if (spec.field_width == -1) {
1041 spec.field_width = 2 * sizeof(void *);
1042 spec.flags |= ZEROPAD;
1044 spec.base = 16;
1046 return number(buf, end, (unsigned long) ptr, spec);
1050 * Helper function to decode printf style format.
1051 * Each call decode a token from the format and return the
1052 * number of characters read (or likely the delta where it wants
1053 * to go on the next call).
1054 * The decoded token is returned through the parameters
1056 * 'h', 'l', or 'L' for integer fields
1057 * 'z' support added 23/7/1999 S.H.
1058 * 'z' changed to 'Z' --davidm 1/25/99
1059 * 't' added for ptrdiff_t
1061 * @fmt: the format string
1062 * @type of the token returned
1063 * @flags: various flags such as +, -, # tokens..
1064 * @field_width: overwritten width
1065 * @base: base of the number (octal, hex, ...)
1066 * @precision: precision of a number
1067 * @qualifier: qualifier of a number (long, size_t, ...)
1069 static noinline_for_stack
1070 int format_decode(const char *fmt, struct printf_spec *spec)
1072 const char *start = fmt;
1074 /* we finished early by reading the field width */
1075 if (spec->type == FORMAT_TYPE_WIDTH) {
1076 if (spec->field_width < 0) {
1077 spec->field_width = -spec->field_width;
1078 spec->flags |= LEFT;
1080 spec->type = FORMAT_TYPE_NONE;
1081 goto precision;
1084 /* we finished early by reading the precision */
1085 if (spec->type == FORMAT_TYPE_PRECISION) {
1086 if (spec->precision < 0)
1087 spec->precision = 0;
1089 spec->type = FORMAT_TYPE_NONE;
1090 goto qualifier;
1093 /* By default */
1094 spec->type = FORMAT_TYPE_NONE;
1096 for (; *fmt ; ++fmt) {
1097 if (*fmt == '%')
1098 break;
1101 /* Return the current non-format string */
1102 if (fmt != start || !*fmt)
1103 return fmt - start;
1105 /* Process flags */
1106 spec->flags = 0;
1108 while (1) { /* this also skips first '%' */
1109 bool found = true;
1111 ++fmt;
1113 switch (*fmt) {
1114 case '-': spec->flags |= LEFT; break;
1115 case '+': spec->flags |= PLUS; break;
1116 case ' ': spec->flags |= SPACE; break;
1117 case '#': spec->flags |= SPECIAL; break;
1118 case '0': spec->flags |= ZEROPAD; break;
1119 default: found = false;
1122 if (!found)
1123 break;
1126 /* get field width */
1127 spec->field_width = -1;
1129 if (isdigit(*fmt))
1130 spec->field_width = skip_atoi(&fmt);
1131 else if (*fmt == '*') {
1132 /* it's the next argument */
1133 spec->type = FORMAT_TYPE_WIDTH;
1134 return ++fmt - start;
1137 precision:
1138 /* get the precision */
1139 spec->precision = -1;
1140 if (*fmt == '.') {
1141 ++fmt;
1142 if (isdigit(*fmt)) {
1143 spec->precision = skip_atoi(&fmt);
1144 if (spec->precision < 0)
1145 spec->precision = 0;
1146 } else if (*fmt == '*') {
1147 /* it's the next argument */
1148 spec->type = FORMAT_TYPE_PRECISION;
1149 return ++fmt - start;
1153 qualifier:
1154 /* get the conversion qualifier */
1155 spec->qualifier = -1;
1156 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1157 TOLOWER(*fmt) == 'z' || *fmt == 't') {
1158 spec->qualifier = *fmt++;
1159 if (unlikely(spec->qualifier == *fmt)) {
1160 if (spec->qualifier == 'l') {
1161 spec->qualifier = 'L';
1162 ++fmt;
1163 } else if (spec->qualifier == 'h') {
1164 spec->qualifier = 'H';
1165 ++fmt;
1170 /* default base */
1171 spec->base = 10;
1172 switch (*fmt) {
1173 case 'c':
1174 spec->type = FORMAT_TYPE_CHAR;
1175 return ++fmt - start;
1177 case 's':
1178 spec->type = FORMAT_TYPE_STR;
1179 return ++fmt - start;
1181 case 'p':
1182 spec->type = FORMAT_TYPE_PTR;
1183 return fmt - start;
1184 /* skip alnum */
1186 case 'n':
1187 spec->type = FORMAT_TYPE_NRCHARS;
1188 return ++fmt - start;
1190 case '%':
1191 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1192 return ++fmt - start;
1194 /* integer number formats - set up the flags and "break" */
1195 case 'o':
1196 spec->base = 8;
1197 break;
1199 case 'x':
1200 spec->flags |= SMALL;
1202 case 'X':
1203 spec->base = 16;
1204 break;
1206 case 'd':
1207 case 'i':
1208 spec->flags |= SIGN;
1209 case 'u':
1210 break;
1212 default:
1213 spec->type = FORMAT_TYPE_INVALID;
1214 return fmt - start;
1217 if (spec->qualifier == 'L')
1218 spec->type = FORMAT_TYPE_LONG_LONG;
1219 else if (spec->qualifier == 'l') {
1220 if (spec->flags & SIGN)
1221 spec->type = FORMAT_TYPE_LONG;
1222 else
1223 spec->type = FORMAT_TYPE_ULONG;
1224 } else if (TOLOWER(spec->qualifier) == 'z') {
1225 spec->type = FORMAT_TYPE_SIZE_T;
1226 } else if (spec->qualifier == 't') {
1227 spec->type = FORMAT_TYPE_PTRDIFF;
1228 } else if (spec->qualifier == 'H') {
1229 if (spec->flags & SIGN)
1230 spec->type = FORMAT_TYPE_BYTE;
1231 else
1232 spec->type = FORMAT_TYPE_UBYTE;
1233 } else if (spec->qualifier == 'h') {
1234 if (spec->flags & SIGN)
1235 spec->type = FORMAT_TYPE_SHORT;
1236 else
1237 spec->type = FORMAT_TYPE_USHORT;
1238 } else {
1239 if (spec->flags & SIGN)
1240 spec->type = FORMAT_TYPE_INT;
1241 else
1242 spec->type = FORMAT_TYPE_UINT;
1245 return ++fmt - start;
1249 * vsnprintf - Format a string and place it in a buffer
1250 * @buf: The buffer to place the result into
1251 * @size: The size of the buffer, including the trailing null space
1252 * @fmt: The format string to use
1253 * @args: Arguments for the format string
1255 * This function follows C99 vsnprintf, but has some extensions:
1256 * %pS output the name of a text symbol with offset
1257 * %ps output the name of a text symbol without offset
1258 * %pF output the name of a function pointer with its offset
1259 * %pf output the name of a function pointer without its offset
1260 * %pR output the address range in a struct resource with decoded flags
1261 * %pr output the address range in a struct resource with raw flags
1262 * %pM output a 6-byte MAC address with colons
1263 * %pm output a 6-byte MAC address without colons
1264 * %pI4 print an IPv4 address without leading zeros
1265 * %pi4 print an IPv4 address with leading zeros
1266 * %pI6 print an IPv6 address with colons
1267 * %pi6 print an IPv6 address without colons
1268 * %pI6c print an IPv6 address as specified by
1269 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
1270 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1271 * case.
1272 * %n is ignored
1274 * The return value is the number of characters which would
1275 * be generated for the given input, excluding the trailing
1276 * '\0', as per ISO C99. If you want to have the exact
1277 * number of characters written into @buf as return value
1278 * (not including the trailing '\0'), use vscnprintf(). If the
1279 * return is greater than or equal to @size, the resulting
1280 * string is truncated.
1282 * Call this function if you are already dealing with a va_list.
1283 * You probably want snprintf() instead.
1285 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1287 unsigned long long num;
1288 char *str, *end;
1289 struct printf_spec spec = {0};
1291 /* Reject out-of-range values early. Large positive sizes are
1292 used for unknown buffer sizes. */
1293 if (WARN_ON_ONCE((int) size < 0))
1294 return 0;
1296 str = buf;
1297 end = buf + size;
1299 /* Make sure end is always >= buf */
1300 if (end < buf) {
1301 end = ((void *)-1);
1302 size = end - buf;
1305 while (*fmt) {
1306 const char *old_fmt = fmt;
1307 int read = format_decode(fmt, &spec);
1309 fmt += read;
1311 switch (spec.type) {
1312 case FORMAT_TYPE_NONE: {
1313 int copy = read;
1314 if (str < end) {
1315 if (copy > end - str)
1316 copy = end - str;
1317 memcpy(str, old_fmt, copy);
1319 str += read;
1320 break;
1323 case FORMAT_TYPE_WIDTH:
1324 spec.field_width = va_arg(args, int);
1325 break;
1327 case FORMAT_TYPE_PRECISION:
1328 spec.precision = va_arg(args, int);
1329 break;
1331 case FORMAT_TYPE_CHAR: {
1332 char c;
1334 if (!(spec.flags & LEFT)) {
1335 while (--spec.field_width > 0) {
1336 if (str < end)
1337 *str = ' ';
1338 ++str;
1342 c = (unsigned char) va_arg(args, int);
1343 if (str < end)
1344 *str = c;
1345 ++str;
1346 while (--spec.field_width > 0) {
1347 if (str < end)
1348 *str = ' ';
1349 ++str;
1351 break;
1354 case FORMAT_TYPE_STR:
1355 str = string(str, end, va_arg(args, char *), spec);
1356 break;
1358 case FORMAT_TYPE_PTR:
1359 str = pointer(fmt+1, str, end, va_arg(args, void *),
1360 spec);
1361 while (isalnum(*fmt))
1362 fmt++;
1363 break;
1365 case FORMAT_TYPE_PERCENT_CHAR:
1366 if (str < end)
1367 *str = '%';
1368 ++str;
1369 break;
1371 case FORMAT_TYPE_INVALID:
1372 if (str < end)
1373 *str = '%';
1374 ++str;
1375 break;
1377 case FORMAT_TYPE_NRCHARS: {
1378 u8 qualifier = spec.qualifier;
1380 if (qualifier == 'l') {
1381 long *ip = va_arg(args, long *);
1382 *ip = (str - buf);
1383 } else if (TOLOWER(qualifier) == 'z') {
1384 size_t *ip = va_arg(args, size_t *);
1385 *ip = (str - buf);
1386 } else {
1387 int *ip = va_arg(args, int *);
1388 *ip = (str - buf);
1390 break;
1393 default:
1394 switch (spec.type) {
1395 case FORMAT_TYPE_LONG_LONG:
1396 num = va_arg(args, long long);
1397 break;
1398 case FORMAT_TYPE_ULONG:
1399 num = va_arg(args, unsigned long);
1400 break;
1401 case FORMAT_TYPE_LONG:
1402 num = va_arg(args, long);
1403 break;
1404 case FORMAT_TYPE_SIZE_T:
1405 num = va_arg(args, size_t);
1406 break;
1407 case FORMAT_TYPE_PTRDIFF:
1408 num = va_arg(args, ptrdiff_t);
1409 break;
1410 case FORMAT_TYPE_UBYTE:
1411 num = (unsigned char) va_arg(args, int);
1412 break;
1413 case FORMAT_TYPE_BYTE:
1414 num = (signed char) va_arg(args, int);
1415 break;
1416 case FORMAT_TYPE_USHORT:
1417 num = (unsigned short) va_arg(args, int);
1418 break;
1419 case FORMAT_TYPE_SHORT:
1420 num = (short) va_arg(args, int);
1421 break;
1422 case FORMAT_TYPE_INT:
1423 num = (int) va_arg(args, int);
1424 break;
1425 default:
1426 num = va_arg(args, unsigned int);
1429 str = number(str, end, num, spec);
1433 if (size > 0) {
1434 if (str < end)
1435 *str = '\0';
1436 else
1437 end[-1] = '\0';
1440 /* the trailing null byte doesn't count towards the total */
1441 return str-buf;
1444 EXPORT_SYMBOL(vsnprintf);
1447 * vscnprintf - Format a string and place it in a buffer
1448 * @buf: The buffer to place the result into
1449 * @size: The size of the buffer, including the trailing null space
1450 * @fmt: The format string to use
1451 * @args: Arguments for the format string
1453 * The return value is the number of characters which have been written into
1454 * the @buf not including the trailing '\0'. If @size is <= 0 the function
1455 * returns 0.
1457 * Call this function if you are already dealing with a va_list.
1458 * You probably want scnprintf() instead.
1460 * See the vsnprintf() documentation for format string extensions over C99.
1462 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1464 int i;
1466 i = vsnprintf(buf, size, fmt, args);
1468 return (i >= size) ? (size - 1) : i;
1470 EXPORT_SYMBOL(vscnprintf);
1473 * snprintf - Format a string and place it in a buffer
1474 * @buf: The buffer to place the result into
1475 * @size: The size of the buffer, including the trailing null space
1476 * @fmt: The format string to use
1477 * @...: Arguments for the format string
1479 * The return value is the number of characters which would be
1480 * generated for the given input, excluding the trailing null,
1481 * as per ISO C99. If the return is greater than or equal to
1482 * @size, the resulting string is truncated.
1484 * See the vsnprintf() documentation for format string extensions over C99.
1486 int snprintf(char *buf, size_t size, const char *fmt, ...)
1488 va_list args;
1489 int i;
1491 va_start(args, fmt);
1492 i = vsnprintf(buf, size, fmt, args);
1493 va_end(args);
1495 return i;
1497 EXPORT_SYMBOL(snprintf);
1500 * scnprintf - Format a string and place it in a buffer
1501 * @buf: The buffer to place the result into
1502 * @size: The size of the buffer, including the trailing null space
1503 * @fmt: The format string to use
1504 * @...: Arguments for the format string
1506 * The return value is the number of characters written into @buf not including
1507 * the trailing '\0'. If @size is == 0 the function returns 0.
1510 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1512 va_list args;
1513 int i;
1515 va_start(args, fmt);
1516 i = vsnprintf(buf, size, fmt, args);
1517 va_end(args);
1519 if (likely(i < size))
1520 return i;
1521 if (size != 0)
1522 return size - 1;
1523 return 0;
1525 EXPORT_SYMBOL(scnprintf);
1528 * vsprintf - Format a string and place it in a buffer
1529 * @buf: The buffer to place the result into
1530 * @fmt: The format string to use
1531 * @args: Arguments for the format string
1533 * The function returns the number of characters written
1534 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1535 * buffer overflows.
1537 * Call this function if you are already dealing with a va_list.
1538 * You probably want sprintf() instead.
1540 * See the vsnprintf() documentation for format string extensions over C99.
1542 int vsprintf(char *buf, const char *fmt, va_list args)
1544 return vsnprintf(buf, INT_MAX, fmt, args);
1546 EXPORT_SYMBOL(vsprintf);
1549 * sprintf - Format a string and place it in a buffer
1550 * @buf: The buffer to place the result into
1551 * @fmt: The format string to use
1552 * @...: Arguments for the format string
1554 * The function returns the number of characters written
1555 * into @buf. Use snprintf() or scnprintf() in order to avoid
1556 * buffer overflows.
1558 * See the vsnprintf() documentation for format string extensions over C99.
1560 int sprintf(char *buf, const char *fmt, ...)
1562 va_list args;
1563 int i;
1565 va_start(args, fmt);
1566 i = vsnprintf(buf, INT_MAX, fmt, args);
1567 va_end(args);
1569 return i;
1571 EXPORT_SYMBOL(sprintf);
1573 #ifdef CONFIG_BINARY_PRINTF
1575 * bprintf service:
1576 * vbin_printf() - VA arguments to binary data
1577 * bstr_printf() - Binary data to text string
1581 * vbin_printf - Parse a format string and place args' binary value in a buffer
1582 * @bin_buf: The buffer to place args' binary value
1583 * @size: The size of the buffer(by words(32bits), not characters)
1584 * @fmt: The format string to use
1585 * @args: Arguments for the format string
1587 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1588 * is skiped.
1590 * The return value is the number of words(32bits) which would be generated for
1591 * the given input.
1593 * NOTE:
1594 * If the return value is greater than @size, the resulting bin_buf is NOT
1595 * valid for bstr_printf().
1597 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1599 struct printf_spec spec = {0};
1600 char *str, *end;
1602 str = (char *)bin_buf;
1603 end = (char *)(bin_buf + size);
1605 #define save_arg(type) \
1606 do { \
1607 if (sizeof(type) == 8) { \
1608 unsigned long long value; \
1609 str = PTR_ALIGN(str, sizeof(u32)); \
1610 value = va_arg(args, unsigned long long); \
1611 if (str + sizeof(type) <= end) { \
1612 *(u32 *)str = *(u32 *)&value; \
1613 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1615 } else { \
1616 unsigned long value; \
1617 str = PTR_ALIGN(str, sizeof(type)); \
1618 value = va_arg(args, int); \
1619 if (str + sizeof(type) <= end) \
1620 *(typeof(type) *)str = (type)value; \
1622 str += sizeof(type); \
1623 } while (0)
1625 while (*fmt) {
1626 int read = format_decode(fmt, &spec);
1628 fmt += read;
1630 switch (spec.type) {
1631 case FORMAT_TYPE_NONE:
1632 case FORMAT_TYPE_INVALID:
1633 case FORMAT_TYPE_PERCENT_CHAR:
1634 break;
1636 case FORMAT_TYPE_WIDTH:
1637 case FORMAT_TYPE_PRECISION:
1638 save_arg(int);
1639 break;
1641 case FORMAT_TYPE_CHAR:
1642 save_arg(char);
1643 break;
1645 case FORMAT_TYPE_STR: {
1646 const char *save_str = va_arg(args, char *);
1647 size_t len;
1649 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1650 || (unsigned long)save_str < PAGE_SIZE)
1651 save_str = "(null)";
1652 len = strlen(save_str) + 1;
1653 if (str + len < end)
1654 memcpy(str, save_str, len);
1655 str += len;
1656 break;
1659 case FORMAT_TYPE_PTR:
1660 save_arg(void *);
1661 /* skip all alphanumeric pointer suffixes */
1662 while (isalnum(*fmt))
1663 fmt++;
1664 break;
1666 case FORMAT_TYPE_NRCHARS: {
1667 /* skip %n 's argument */
1668 u8 qualifier = spec.qualifier;
1669 void *skip_arg;
1670 if (qualifier == 'l')
1671 skip_arg = va_arg(args, long *);
1672 else if (TOLOWER(qualifier) == 'z')
1673 skip_arg = va_arg(args, size_t *);
1674 else
1675 skip_arg = va_arg(args, int *);
1676 break;
1679 default:
1680 switch (spec.type) {
1682 case FORMAT_TYPE_LONG_LONG:
1683 save_arg(long long);
1684 break;
1685 case FORMAT_TYPE_ULONG:
1686 case FORMAT_TYPE_LONG:
1687 save_arg(unsigned long);
1688 break;
1689 case FORMAT_TYPE_SIZE_T:
1690 save_arg(size_t);
1691 break;
1692 case FORMAT_TYPE_PTRDIFF:
1693 save_arg(ptrdiff_t);
1694 break;
1695 case FORMAT_TYPE_UBYTE:
1696 case FORMAT_TYPE_BYTE:
1697 save_arg(char);
1698 break;
1699 case FORMAT_TYPE_USHORT:
1700 case FORMAT_TYPE_SHORT:
1701 save_arg(short);
1702 break;
1703 default:
1704 save_arg(int);
1709 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1710 #undef save_arg
1712 EXPORT_SYMBOL_GPL(vbin_printf);
1715 * bstr_printf - Format a string from binary arguments and place it in a buffer
1716 * @buf: The buffer to place the result into
1717 * @size: The size of the buffer, including the trailing null space
1718 * @fmt: The format string to use
1719 * @bin_buf: Binary arguments for the format string
1721 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1722 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1723 * a binary buffer that generated by vbin_printf.
1725 * The format follows C99 vsnprintf, but has some extensions:
1726 * see vsnprintf comment for details.
1728 * The return value is the number of characters which would
1729 * be generated for the given input, excluding the trailing
1730 * '\0', as per ISO C99. If you want to have the exact
1731 * number of characters written into @buf as return value
1732 * (not including the trailing '\0'), use vscnprintf(). If the
1733 * return is greater than or equal to @size, the resulting
1734 * string is truncated.
1736 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1738 struct printf_spec spec = {0};
1739 char *str, *end;
1740 const char *args = (const char *)bin_buf;
1742 if (WARN_ON_ONCE((int) size < 0))
1743 return 0;
1745 str = buf;
1746 end = buf + size;
1748 #define get_arg(type) \
1749 ({ \
1750 typeof(type) value; \
1751 if (sizeof(type) == 8) { \
1752 args = PTR_ALIGN(args, sizeof(u32)); \
1753 *(u32 *)&value = *(u32 *)args; \
1754 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1755 } else { \
1756 args = PTR_ALIGN(args, sizeof(type)); \
1757 value = *(typeof(type) *)args; \
1759 args += sizeof(type); \
1760 value; \
1763 /* Make sure end is always >= buf */
1764 if (end < buf) {
1765 end = ((void *)-1);
1766 size = end - buf;
1769 while (*fmt) {
1770 const char *old_fmt = fmt;
1771 int read = format_decode(fmt, &spec);
1773 fmt += read;
1775 switch (spec.type) {
1776 case FORMAT_TYPE_NONE: {
1777 int copy = read;
1778 if (str < end) {
1779 if (copy > end - str)
1780 copy = end - str;
1781 memcpy(str, old_fmt, copy);
1783 str += read;
1784 break;
1787 case FORMAT_TYPE_WIDTH:
1788 spec.field_width = get_arg(int);
1789 break;
1791 case FORMAT_TYPE_PRECISION:
1792 spec.precision = get_arg(int);
1793 break;
1795 case FORMAT_TYPE_CHAR: {
1796 char c;
1798 if (!(spec.flags & LEFT)) {
1799 while (--spec.field_width > 0) {
1800 if (str < end)
1801 *str = ' ';
1802 ++str;
1805 c = (unsigned char) get_arg(char);
1806 if (str < end)
1807 *str = c;
1808 ++str;
1809 while (--spec.field_width > 0) {
1810 if (str < end)
1811 *str = ' ';
1812 ++str;
1814 break;
1817 case FORMAT_TYPE_STR: {
1818 const char *str_arg = args;
1819 args += strlen(str_arg) + 1;
1820 str = string(str, end, (char *)str_arg, spec);
1821 break;
1824 case FORMAT_TYPE_PTR:
1825 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1826 while (isalnum(*fmt))
1827 fmt++;
1828 break;
1830 case FORMAT_TYPE_PERCENT_CHAR:
1831 case FORMAT_TYPE_INVALID:
1832 if (str < end)
1833 *str = '%';
1834 ++str;
1835 break;
1837 case FORMAT_TYPE_NRCHARS:
1838 /* skip */
1839 break;
1841 default: {
1842 unsigned long long num;
1844 switch (spec.type) {
1846 case FORMAT_TYPE_LONG_LONG:
1847 num = get_arg(long long);
1848 break;
1849 case FORMAT_TYPE_ULONG:
1850 case FORMAT_TYPE_LONG:
1851 num = get_arg(unsigned long);
1852 break;
1853 case FORMAT_TYPE_SIZE_T:
1854 num = get_arg(size_t);
1855 break;
1856 case FORMAT_TYPE_PTRDIFF:
1857 num = get_arg(ptrdiff_t);
1858 break;
1859 case FORMAT_TYPE_UBYTE:
1860 num = get_arg(unsigned char);
1861 break;
1862 case FORMAT_TYPE_BYTE:
1863 num = get_arg(signed char);
1864 break;
1865 case FORMAT_TYPE_USHORT:
1866 num = get_arg(unsigned short);
1867 break;
1868 case FORMAT_TYPE_SHORT:
1869 num = get_arg(short);
1870 break;
1871 case FORMAT_TYPE_UINT:
1872 num = get_arg(unsigned int);
1873 break;
1874 default:
1875 num = get_arg(int);
1878 str = number(str, end, num, spec);
1879 } /* default: */
1880 } /* switch(spec.type) */
1881 } /* while(*fmt) */
1883 if (size > 0) {
1884 if (str < end)
1885 *str = '\0';
1886 else
1887 end[-1] = '\0';
1890 #undef get_arg
1892 /* the trailing null byte doesn't count towards the total */
1893 return str - buf;
1895 EXPORT_SYMBOL_GPL(bstr_printf);
1898 * bprintf - Parse a format string and place args' binary value in a buffer
1899 * @bin_buf: The buffer to place args' binary value
1900 * @size: The size of the buffer(by words(32bits), not characters)
1901 * @fmt: The format string to use
1902 * @...: Arguments for the format string
1904 * The function returns the number of words(u32) written
1905 * into @bin_buf.
1907 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1909 va_list args;
1910 int ret;
1912 va_start(args, fmt);
1913 ret = vbin_printf(bin_buf, size, fmt, args);
1914 va_end(args);
1916 return ret;
1918 EXPORT_SYMBOL_GPL(bprintf);
1920 #endif /* CONFIG_BINARY_PRINTF */
1923 * vsscanf - Unformat a buffer into a list of arguments
1924 * @buf: input buffer
1925 * @fmt: format of buffer
1926 * @args: arguments
1928 int vsscanf(const char *buf, const char *fmt, va_list args)
1930 const char *str = buf;
1931 char *next;
1932 char digit;
1933 int num = 0;
1934 u8 qualifier;
1935 u8 base;
1936 s16 field_width;
1937 bool is_sign;
1939 while (*fmt && *str) {
1940 /* skip any white space in format */
1941 /* white space in format matchs any amount of
1942 * white space, including none, in the input.
1944 if (isspace(*fmt)) {
1945 fmt = skip_spaces(++fmt);
1946 str = skip_spaces(str);
1949 /* anything that is not a conversion must match exactly */
1950 if (*fmt != '%' && *fmt) {
1951 if (*fmt++ != *str++)
1952 break;
1953 continue;
1956 if (!*fmt)
1957 break;
1958 ++fmt;
1960 /* skip this conversion.
1961 * advance both strings to next white space
1963 if (*fmt == '*') {
1964 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1965 fmt++;
1966 while (!isspace(*str) && *str)
1967 str++;
1968 continue;
1971 /* get field width */
1972 field_width = -1;
1973 if (isdigit(*fmt))
1974 field_width = skip_atoi(&fmt);
1976 /* get conversion qualifier */
1977 qualifier = -1;
1978 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1979 TOLOWER(*fmt) == 'z') {
1980 qualifier = *fmt++;
1981 if (unlikely(qualifier == *fmt)) {
1982 if (qualifier == 'h') {
1983 qualifier = 'H';
1984 fmt++;
1985 } else if (qualifier == 'l') {
1986 qualifier = 'L';
1987 fmt++;
1992 if (!*fmt || !*str)
1993 break;
1995 base = 10;
1996 is_sign = 0;
1998 switch (*fmt++) {
1999 case 'c':
2001 char *s = (char *)va_arg(args, char*);
2002 if (field_width == -1)
2003 field_width = 1;
2004 do {
2005 *s++ = *str++;
2006 } while (--field_width > 0 && *str);
2007 num++;
2009 continue;
2010 case 's':
2012 char *s = (char *)va_arg(args, char *);
2013 if (field_width == -1)
2014 field_width = SHRT_MAX;
2015 /* first, skip leading white space in buffer */
2016 str = skip_spaces(str);
2018 /* now copy until next white space */
2019 while (*str && !isspace(*str) && field_width--)
2020 *s++ = *str++;
2021 *s = '\0';
2022 num++;
2024 continue;
2025 case 'n':
2026 /* return number of characters read so far */
2028 int *i = (int *)va_arg(args, int*);
2029 *i = str - buf;
2031 continue;
2032 case 'o':
2033 base = 8;
2034 break;
2035 case 'x':
2036 case 'X':
2037 base = 16;
2038 break;
2039 case 'i':
2040 base = 0;
2041 case 'd':
2042 is_sign = 1;
2043 case 'u':
2044 break;
2045 case '%':
2046 /* looking for '%' in str */
2047 if (*str++ != '%')
2048 return num;
2049 continue;
2050 default:
2051 /* invalid format; stop here */
2052 return num;
2055 /* have some sort of integer conversion.
2056 * first, skip white space in buffer.
2058 str = skip_spaces(str);
2060 digit = *str;
2061 if (is_sign && digit == '-')
2062 digit = *(str + 1);
2064 if (!digit
2065 || (base == 16 && !isxdigit(digit))
2066 || (base == 10 && !isdigit(digit))
2067 || (base == 8 && (!isdigit(digit) || digit > '7'))
2068 || (base == 0 && !isdigit(digit)))
2069 break;
2071 switch (qualifier) {
2072 case 'H': /* that's 'hh' in format */
2073 if (is_sign) {
2074 signed char *s = (signed char *)va_arg(args, signed char *);
2075 *s = (signed char)simple_strtol(str, &next, base);
2076 } else {
2077 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
2078 *s = (unsigned char)simple_strtoul(str, &next, base);
2080 break;
2081 case 'h':
2082 if (is_sign) {
2083 short *s = (short *)va_arg(args, short *);
2084 *s = (short)simple_strtol(str, &next, base);
2085 } else {
2086 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
2087 *s = (unsigned short)simple_strtoul(str, &next, base);
2089 break;
2090 case 'l':
2091 if (is_sign) {
2092 long *l = (long *)va_arg(args, long *);
2093 *l = simple_strtol(str, &next, base);
2094 } else {
2095 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2096 *l = simple_strtoul(str, &next, base);
2098 break;
2099 case 'L':
2100 if (is_sign) {
2101 long long *l = (long long *)va_arg(args, long long *);
2102 *l = simple_strtoll(str, &next, base);
2103 } else {
2104 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2105 *l = simple_strtoull(str, &next, base);
2107 break;
2108 case 'Z':
2109 case 'z':
2111 size_t *s = (size_t *)va_arg(args, size_t *);
2112 *s = (size_t)simple_strtoul(str, &next, base);
2114 break;
2115 default:
2116 if (is_sign) {
2117 int *i = (int *)va_arg(args, int *);
2118 *i = (int)simple_strtol(str, &next, base);
2119 } else {
2120 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2121 *i = (unsigned int)simple_strtoul(str, &next, base);
2123 break;
2125 num++;
2127 if (!next)
2128 break;
2129 str = next;
2133 * Now we've come all the way through so either the input string or the
2134 * format ended. In the former case, there can be a %n at the current
2135 * position in the format that needs to be filled.
2137 if (*fmt == '%' && *(fmt + 1) == 'n') {
2138 int *p = (int *)va_arg(args, int *);
2139 *p = str - buf;
2142 return num;
2144 EXPORT_SYMBOL(vsscanf);
2147 * sscanf - Unformat a buffer into a list of arguments
2148 * @buf: input buffer
2149 * @fmt: formatting of buffer
2150 * @...: resulting arguments
2152 int sscanf(const char *buf, const char *fmt, ...)
2154 va_list args;
2155 int i;
2157 va_start(args, fmt);
2158 i = vsscanf(buf, fmt, args);
2159 va_end(args);
2161 return i;
2163 EXPORT_SYMBOL(sscanf);