mm/memcontrol.c: suppress uninitialized-var warning with older gcc's
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / lib / vsprintf.c
blob02bcdd5feac43aca15528252cc6bfba7ea8a7a4f
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);
123 static noinline_for_stack
124 int skip_atoi(const char **s)
126 int i = 0;
128 while (isdigit(**s))
129 i = i*10 + *((*s)++) - '0';
131 return i;
134 /* Decimal conversion is by far the most typical, and is used
135 * for /proc and /sys data. This directly impacts e.g. top performance
136 * with many processes running. We optimize it for speed
137 * using code from
138 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
139 * (with permission from the author, Douglas W. Jones). */
141 /* Formats correctly any integer in [0,99999].
142 * Outputs from one to five digits depending on input.
143 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
144 static noinline_for_stack
145 char *put_dec_trunc(char *buf, unsigned q)
147 unsigned d3, d2, d1, d0;
148 d1 = (q>>4) & 0xf;
149 d2 = (q>>8) & 0xf;
150 d3 = (q>>12);
152 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
153 q = (d0 * 0xcd) >> 11;
154 d0 = d0 - 10*q;
155 *buf++ = d0 + '0'; /* least significant digit */
156 d1 = q + 9*d3 + 5*d2 + d1;
157 if (d1 != 0) {
158 q = (d1 * 0xcd) >> 11;
159 d1 = d1 - 10*q;
160 *buf++ = d1 + '0'; /* next digit */
162 d2 = q + 2*d2;
163 if ((d2 != 0) || (d3 != 0)) {
164 q = (d2 * 0xd) >> 7;
165 d2 = d2 - 10*q;
166 *buf++ = d2 + '0'; /* next digit */
168 d3 = q + 4*d3;
169 if (d3 != 0) {
170 q = (d3 * 0xcd) >> 11;
171 d3 = d3 - 10*q;
172 *buf++ = d3 + '0'; /* next digit */
173 if (q != 0)
174 *buf++ = q + '0'; /* most sign. digit */
179 return buf;
181 /* Same with if's removed. Always emits five digits */
182 static noinline_for_stack
183 char *put_dec_full(char *buf, unsigned q)
185 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
186 /* but anyway, gcc produces better code with full-sized ints */
187 unsigned d3, d2, d1, d0;
188 d1 = (q>>4) & 0xf;
189 d2 = (q>>8) & 0xf;
190 d3 = (q>>12);
193 * Possible ways to approx. divide by 10
194 * gcc -O2 replaces multiply with shifts and adds
195 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
196 * (x * 0x67) >> 10: 1100111
197 * (x * 0x34) >> 9: 110100 - same
198 * (x * 0x1a) >> 8: 11010 - same
199 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
201 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
202 q = (d0 * 0xcd) >> 11;
203 d0 = d0 - 10*q;
204 *buf++ = d0 + '0';
205 d1 = q + 9*d3 + 5*d2 + d1;
206 q = (d1 * 0xcd) >> 11;
207 d1 = d1 - 10*q;
208 *buf++ = d1 + '0';
210 d2 = q + 2*d2;
211 q = (d2 * 0xd) >> 7;
212 d2 = d2 - 10*q;
213 *buf++ = d2 + '0';
215 d3 = q + 4*d3;
216 q = (d3 * 0xcd) >> 11; /* - shorter code */
217 /* q = (d3 * 0x67) >> 10; - would also work */
218 d3 = d3 - 10*q;
219 *buf++ = d3 + '0';
220 *buf++ = q + '0';
222 return buf;
224 /* No inlining helps gcc to use registers better */
225 static noinline_for_stack
226 char *put_dec(char *buf, unsigned long long num)
228 while (1) {
229 unsigned rem;
230 if (num < 100000)
231 return put_dec_trunc(buf, num);
232 rem = do_div(num, 100000);
233 buf = put_dec_full(buf, rem);
237 #define ZEROPAD 1 /* pad with zero */
238 #define SIGN 2 /* unsigned/signed long */
239 #define PLUS 4 /* show plus */
240 #define SPACE 8 /* space if plus */
241 #define LEFT 16 /* left justified */
242 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
243 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
245 enum format_type {
246 FORMAT_TYPE_NONE, /* Just a string part */
247 FORMAT_TYPE_WIDTH,
248 FORMAT_TYPE_PRECISION,
249 FORMAT_TYPE_CHAR,
250 FORMAT_TYPE_STR,
251 FORMAT_TYPE_PTR,
252 FORMAT_TYPE_PERCENT_CHAR,
253 FORMAT_TYPE_INVALID,
254 FORMAT_TYPE_LONG_LONG,
255 FORMAT_TYPE_ULONG,
256 FORMAT_TYPE_LONG,
257 FORMAT_TYPE_UBYTE,
258 FORMAT_TYPE_BYTE,
259 FORMAT_TYPE_USHORT,
260 FORMAT_TYPE_SHORT,
261 FORMAT_TYPE_UINT,
262 FORMAT_TYPE_INT,
263 FORMAT_TYPE_NRCHARS,
264 FORMAT_TYPE_SIZE_T,
265 FORMAT_TYPE_PTRDIFF
268 struct printf_spec {
269 u8 type; /* format_type enum */
270 u8 flags; /* flags to number() */
271 u8 base; /* number base, 8, 10 or 16 only */
272 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
273 s16 field_width; /* width of output field */
274 s16 precision; /* # of digits/chars */
277 static noinline_for_stack
278 char *number(char *buf, char *end, unsigned long long num,
279 struct printf_spec spec)
281 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
282 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
284 char tmp[66];
285 char sign;
286 char locase;
287 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
288 int i;
290 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
291 * produces same digits or (maybe lowercased) letters */
292 locase = (spec.flags & SMALL);
293 if (spec.flags & LEFT)
294 spec.flags &= ~ZEROPAD;
295 sign = 0;
296 if (spec.flags & SIGN) {
297 if ((signed long long)num < 0) {
298 sign = '-';
299 num = -(signed long long)num;
300 spec.field_width--;
301 } else if (spec.flags & PLUS) {
302 sign = '+';
303 spec.field_width--;
304 } else if (spec.flags & SPACE) {
305 sign = ' ';
306 spec.field_width--;
309 if (need_pfx) {
310 spec.field_width--;
311 if (spec.base == 16)
312 spec.field_width--;
315 /* generate full string in tmp[], in reverse order */
316 i = 0;
317 if (num == 0)
318 tmp[i++] = '0';
319 /* Generic code, for any base:
320 else do {
321 tmp[i++] = (digits[do_div(num,base)] | locase);
322 } while (num != 0);
324 else if (spec.base != 10) { /* 8 or 16 */
325 int mask = spec.base - 1;
326 int shift = 3;
328 if (spec.base == 16)
329 shift = 4;
330 do {
331 tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
332 num >>= shift;
333 } while (num);
334 } else { /* base 10 */
335 i = put_dec(tmp, num) - tmp;
338 /* printing 100 using %2d gives "100", not "00" */
339 if (i > spec.precision)
340 spec.precision = i;
341 /* leading space padding */
342 spec.field_width -= spec.precision;
343 if (!(spec.flags & (ZEROPAD+LEFT))) {
344 while (--spec.field_width >= 0) {
345 if (buf < end)
346 *buf = ' ';
347 ++buf;
350 /* sign */
351 if (sign) {
352 if (buf < end)
353 *buf = sign;
354 ++buf;
356 /* "0x" / "0" prefix */
357 if (need_pfx) {
358 if (buf < end)
359 *buf = '0';
360 ++buf;
361 if (spec.base == 16) {
362 if (buf < end)
363 *buf = ('X' | locase);
364 ++buf;
367 /* zero or space padding */
368 if (!(spec.flags & LEFT)) {
369 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
370 while (--spec.field_width >= 0) {
371 if (buf < end)
372 *buf = c;
373 ++buf;
376 /* hmm even more zero padding? */
377 while (i <= --spec.precision) {
378 if (buf < end)
379 *buf = '0';
380 ++buf;
382 /* actual digits of result */
383 while (--i >= 0) {
384 if (buf < end)
385 *buf = tmp[i];
386 ++buf;
388 /* trailing space padding */
389 while (--spec.field_width >= 0) {
390 if (buf < end)
391 *buf = ' ';
392 ++buf;
395 return buf;
398 static noinline_for_stack
399 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
401 int len, i;
403 if ((unsigned long)s < PAGE_SIZE)
404 s = "(null)";
406 len = strnlen(s, spec.precision);
408 if (!(spec.flags & LEFT)) {
409 while (len < spec.field_width--) {
410 if (buf < end)
411 *buf = ' ';
412 ++buf;
415 for (i = 0; i < len; ++i) {
416 if (buf < end)
417 *buf = *s;
418 ++buf; ++s;
420 while (len < spec.field_width--) {
421 if (buf < end)
422 *buf = ' ';
423 ++buf;
426 return buf;
429 static noinline_for_stack
430 char *symbol_string(char *buf, char *end, void *ptr,
431 struct printf_spec spec, char ext)
433 unsigned long value = (unsigned long) ptr;
434 #ifdef CONFIG_KALLSYMS
435 char sym[KSYM_SYMBOL_LEN];
436 if (ext != 'f' && ext != 's')
437 sprint_symbol(sym, value);
438 else
439 kallsyms_lookup(value, NULL, NULL, NULL, sym);
441 return string(buf, end, sym, spec);
442 #else
443 spec.field_width = 2 * sizeof(void *);
444 spec.flags |= SPECIAL | SMALL | ZEROPAD;
445 spec.base = 16;
447 return number(buf, end, value, spec);
448 #endif
451 static noinline_for_stack
452 char *resource_string(char *buf, char *end, struct resource *res,
453 struct printf_spec spec, const char *fmt)
455 #ifndef IO_RSRC_PRINTK_SIZE
456 #define IO_RSRC_PRINTK_SIZE 6
457 #endif
459 #ifndef MEM_RSRC_PRINTK_SIZE
460 #define MEM_RSRC_PRINTK_SIZE 10
461 #endif
462 static const struct printf_spec io_spec = {
463 .base = 16,
464 .field_width = IO_RSRC_PRINTK_SIZE,
465 .precision = -1,
466 .flags = SPECIAL | SMALL | ZEROPAD,
468 static const struct printf_spec mem_spec = {
469 .base = 16,
470 .field_width = MEM_RSRC_PRINTK_SIZE,
471 .precision = -1,
472 .flags = SPECIAL | SMALL | ZEROPAD,
474 static const struct printf_spec bus_spec = {
475 .base = 16,
476 .field_width = 2,
477 .precision = -1,
478 .flags = SMALL | ZEROPAD,
480 static const struct printf_spec dec_spec = {
481 .base = 10,
482 .precision = -1,
483 .flags = 0,
485 static const struct printf_spec str_spec = {
486 .field_width = -1,
487 .precision = 10,
488 .flags = LEFT,
490 static const struct printf_spec flag_spec = {
491 .base = 16,
492 .precision = -1,
493 .flags = SPECIAL | SMALL,
496 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
497 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
498 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
499 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
500 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
501 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
502 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
503 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
505 char *p = sym, *pend = sym + sizeof(sym);
506 int decode = (fmt[0] == 'R') ? 1 : 0;
507 const struct printf_spec *specp;
509 *p++ = '[';
510 if (res->flags & IORESOURCE_IO) {
511 p = string(p, pend, "io ", str_spec);
512 specp = &io_spec;
513 } else if (res->flags & IORESOURCE_MEM) {
514 p = string(p, pend, "mem ", str_spec);
515 specp = &mem_spec;
516 } else if (res->flags & IORESOURCE_IRQ) {
517 p = string(p, pend, "irq ", str_spec);
518 specp = &dec_spec;
519 } else if (res->flags & IORESOURCE_DMA) {
520 p = string(p, pend, "dma ", str_spec);
521 specp = &dec_spec;
522 } else if (res->flags & IORESOURCE_BUS) {
523 p = string(p, pend, "bus ", str_spec);
524 specp = &bus_spec;
525 } else {
526 p = string(p, pend, "??? ", str_spec);
527 specp = &mem_spec;
528 decode = 0;
530 p = number(p, pend, res->start, *specp);
531 if (res->start != res->end) {
532 *p++ = '-';
533 p = number(p, pend, res->end, *specp);
535 if (decode) {
536 if (res->flags & IORESOURCE_MEM_64)
537 p = string(p, pend, " 64bit", str_spec);
538 if (res->flags & IORESOURCE_PREFETCH)
539 p = string(p, pend, " pref", str_spec);
540 if (res->flags & IORESOURCE_WINDOW)
541 p = string(p, pend, " window", str_spec);
542 if (res->flags & IORESOURCE_DISABLED)
543 p = string(p, pend, " disabled", str_spec);
544 } else {
545 p = string(p, pend, " flags ", str_spec);
546 p = number(p, pend, res->flags, flag_spec);
548 *p++ = ']';
549 *p = '\0';
551 return string(buf, end, sym, spec);
554 static noinline_for_stack
555 char *mac_address_string(char *buf, char *end, u8 *addr,
556 struct printf_spec spec, const char *fmt)
558 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
559 char *p = mac_addr;
560 int i;
561 char separator;
563 if (fmt[1] == 'F') { /* FDDI canonical format */
564 separator = '-';
565 } else {
566 separator = ':';
569 for (i = 0; i < 6; i++) {
570 p = pack_hex_byte(p, addr[i]);
571 if (fmt[0] == 'M' && i != 5)
572 *p++ = separator;
574 *p = '\0';
576 return string(buf, end, mac_addr, spec);
579 static noinline_for_stack
580 char *ip4_string(char *p, const u8 *addr, const char *fmt)
582 int i;
583 bool leading_zeros = (fmt[0] == 'i');
584 int index;
585 int step;
587 switch (fmt[2]) {
588 case 'h':
589 #ifdef __BIG_ENDIAN
590 index = 0;
591 step = 1;
592 #else
593 index = 3;
594 step = -1;
595 #endif
596 break;
597 case 'l':
598 index = 3;
599 step = -1;
600 break;
601 case 'n':
602 case 'b':
603 default:
604 index = 0;
605 step = 1;
606 break;
608 for (i = 0; i < 4; i++) {
609 char temp[3]; /* hold each IP quad in reverse order */
610 int digits = put_dec_trunc(temp, addr[index]) - temp;
611 if (leading_zeros) {
612 if (digits < 3)
613 *p++ = '0';
614 if (digits < 2)
615 *p++ = '0';
617 /* reverse the digits in the quad */
618 while (digits--)
619 *p++ = temp[digits];
620 if (i < 3)
621 *p++ = '.';
622 index += step;
624 *p = '\0';
626 return p;
629 static noinline_for_stack
630 char *ip6_compressed_string(char *p, const char *addr)
632 int i, j, range;
633 unsigned char zerolength[8];
634 int longest = 1;
635 int colonpos = -1;
636 u16 word;
637 u8 hi, lo;
638 bool needcolon = false;
639 bool useIPv4;
640 struct in6_addr in6;
642 memcpy(&in6, addr, sizeof(struct in6_addr));
644 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
646 memset(zerolength, 0, sizeof(zerolength));
648 if (useIPv4)
649 range = 6;
650 else
651 range = 8;
653 /* find position of longest 0 run */
654 for (i = 0; i < range; i++) {
655 for (j = i; j < range; j++) {
656 if (in6.s6_addr16[j] != 0)
657 break;
658 zerolength[i]++;
661 for (i = 0; i < range; i++) {
662 if (zerolength[i] > longest) {
663 longest = zerolength[i];
664 colonpos = i;
668 /* emit address */
669 for (i = 0; i < range; i++) {
670 if (i == colonpos) {
671 if (needcolon || i == 0)
672 *p++ = ':';
673 *p++ = ':';
674 needcolon = false;
675 i += longest - 1;
676 continue;
678 if (needcolon) {
679 *p++ = ':';
680 needcolon = false;
682 /* hex u16 without leading 0s */
683 word = ntohs(in6.s6_addr16[i]);
684 hi = word >> 8;
685 lo = word & 0xff;
686 if (hi) {
687 if (hi > 0x0f)
688 p = pack_hex_byte(p, hi);
689 else
690 *p++ = hex_asc_lo(hi);
691 p = pack_hex_byte(p, lo);
693 else if (lo > 0x0f)
694 p = pack_hex_byte(p, lo);
695 else
696 *p++ = hex_asc_lo(lo);
697 needcolon = true;
700 if (useIPv4) {
701 if (needcolon)
702 *p++ = ':';
703 p = ip4_string(p, &in6.s6_addr[12], "I4");
705 *p = '\0';
707 return p;
710 static noinline_for_stack
711 char *ip6_string(char *p, const char *addr, const char *fmt)
713 int i;
715 for (i = 0; i < 8; i++) {
716 p = pack_hex_byte(p, *addr++);
717 p = pack_hex_byte(p, *addr++);
718 if (fmt[0] == 'I' && i != 7)
719 *p++ = ':';
721 *p = '\0';
723 return p;
726 static noinline_for_stack
727 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
728 struct printf_spec spec, const char *fmt)
730 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
732 if (fmt[0] == 'I' && fmt[2] == 'c')
733 ip6_compressed_string(ip6_addr, addr);
734 else
735 ip6_string(ip6_addr, addr, fmt);
737 return string(buf, end, ip6_addr, spec);
740 static noinline_for_stack
741 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
742 struct printf_spec spec, const char *fmt)
744 char ip4_addr[sizeof("255.255.255.255")];
746 ip4_string(ip4_addr, addr, fmt);
748 return string(buf, end, ip4_addr, spec);
751 static noinline_for_stack
752 char *uuid_string(char *buf, char *end, const u8 *addr,
753 struct printf_spec spec, const char *fmt)
755 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
756 char *p = uuid;
757 int i;
758 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
759 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
760 const u8 *index = be;
761 bool uc = false;
763 switch (*(++fmt)) {
764 case 'L':
765 uc = true; /* fall-through */
766 case 'l':
767 index = le;
768 break;
769 case 'B':
770 uc = true;
771 break;
774 for (i = 0; i < 16; i++) {
775 p = pack_hex_byte(p, addr[index[i]]);
776 switch (i) {
777 case 3:
778 case 5:
779 case 7:
780 case 9:
781 *p++ = '-';
782 break;
786 *p = 0;
788 if (uc) {
789 p = uuid;
790 do {
791 *p = toupper(*p);
792 } while (*(++p));
795 return string(buf, end, uuid, spec);
798 int kptr_restrict = 1;
801 * Show a '%p' thing. A kernel extension is that the '%p' is followed
802 * by an extra set of alphanumeric characters that are extended format
803 * specifiers.
805 * Right now we handle:
807 * - 'F' For symbolic function descriptor pointers with offset
808 * - 'f' For simple symbolic function names without offset
809 * - 'S' For symbolic direct pointers with offset
810 * - 's' For symbolic direct pointers without offset
811 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
812 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
813 * - 'M' For a 6-byte MAC address, it prints the address in the
814 * usual colon-separated hex notation
815 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
816 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
817 * with a dash-separated hex notation
818 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
819 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
820 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
821 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
822 * IPv6 omits the colons (01020304...0f)
823 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
824 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
825 * - 'I6c' for IPv6 addresses printed as specified by
826 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
827 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
828 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
829 * Options for %pU are:
830 * b big endian lower case hex (default)
831 * B big endian UPPER case hex
832 * l little endian lower case hex
833 * L little endian UPPER case hex
834 * big endian output byte order is:
835 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
836 * little endian output byte order is:
837 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
838 * - 'V' For a struct va_format which contains a format string * and va_list *,
839 * call vsnprintf(->format, *->va_list).
840 * Implements a "recursive vsnprintf".
841 * Do not use this feature without some mechanism to verify the
842 * correctness of the format string and va_list arguments.
843 * - 'K' For a kernel pointer that should be hidden from unprivileged users
845 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
846 * function pointers are really function descriptors, which contain a
847 * pointer to the real address.
849 static noinline_for_stack
850 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
851 struct printf_spec spec)
853 if (!ptr && *fmt != 'K') {
855 * Print (null) with the same width as a pointer so it makes
856 * tabular output look nice.
858 if (spec.field_width == -1)
859 spec.field_width = 2 * sizeof(void *);
860 return string(buf, end, "(null)", spec);
863 switch (*fmt) {
864 case 'F':
865 case 'f':
866 ptr = dereference_function_descriptor(ptr);
867 /* Fallthrough */
868 case 'S':
869 case 's':
870 return symbol_string(buf, end, ptr, spec, *fmt);
871 case 'R':
872 case 'r':
873 return resource_string(buf, end, ptr, spec, fmt);
874 case 'M': /* Colon separated: 00:01:02:03:04:05 */
875 case 'm': /* Contiguous: 000102030405 */
876 /* [mM]F (FDDI, bit reversed) */
877 return mac_address_string(buf, end, ptr, spec, fmt);
878 case 'I': /* Formatted IP supported
879 * 4: 1.2.3.4
880 * 6: 0001:0203:...:0708
881 * 6c: 1::708 or 1::1.2.3.4
883 case 'i': /* Contiguous:
884 * 4: 001.002.003.004
885 * 6: 000102...0f
887 switch (fmt[1]) {
888 case '6':
889 return ip6_addr_string(buf, end, ptr, spec, fmt);
890 case '4':
891 return ip4_addr_string(buf, end, ptr, spec, fmt);
893 break;
894 case 'U':
895 return uuid_string(buf, end, ptr, spec, fmt);
896 case 'V':
897 return buf + vsnprintf(buf, end - buf,
898 ((struct va_format *)ptr)->fmt,
899 *(((struct va_format *)ptr)->va));
900 case 'K':
902 * %pK cannot be used in IRQ context because its test
903 * for CAP_SYSLOG would be meaningless.
905 if (in_irq() || in_serving_softirq() || in_nmi()) {
906 if (spec.field_width == -1)
907 spec.field_width = 2 * sizeof(void *);
908 return string(buf, end, "pK-error", spec);
910 if (!((kptr_restrict == 0) ||
911 (kptr_restrict == 1 &&
912 has_capability_noaudit(current, CAP_SYSLOG))))
913 ptr = NULL;
914 break;
916 spec.flags |= SMALL;
917 if (spec.field_width == -1) {
918 spec.field_width = 2 * sizeof(void *);
919 spec.flags |= ZEROPAD;
921 spec.base = 16;
923 return number(buf, end, (unsigned long) ptr, spec);
927 * Helper function to decode printf style format.
928 * Each call decode a token from the format and return the
929 * number of characters read (or likely the delta where it wants
930 * to go on the next call).
931 * The decoded token is returned through the parameters
933 * 'h', 'l', or 'L' for integer fields
934 * 'z' support added 23/7/1999 S.H.
935 * 'z' changed to 'Z' --davidm 1/25/99
936 * 't' added for ptrdiff_t
938 * @fmt: the format string
939 * @type of the token returned
940 * @flags: various flags such as +, -, # tokens..
941 * @field_width: overwritten width
942 * @base: base of the number (octal, hex, ...)
943 * @precision: precision of a number
944 * @qualifier: qualifier of a number (long, size_t, ...)
946 static noinline_for_stack
947 int format_decode(const char *fmt, struct printf_spec *spec)
949 const char *start = fmt;
951 /* we finished early by reading the field width */
952 if (spec->type == FORMAT_TYPE_WIDTH) {
953 if (spec->field_width < 0) {
954 spec->field_width = -spec->field_width;
955 spec->flags |= LEFT;
957 spec->type = FORMAT_TYPE_NONE;
958 goto precision;
961 /* we finished early by reading the precision */
962 if (spec->type == FORMAT_TYPE_PRECISION) {
963 if (spec->precision < 0)
964 spec->precision = 0;
966 spec->type = FORMAT_TYPE_NONE;
967 goto qualifier;
970 /* By default */
971 spec->type = FORMAT_TYPE_NONE;
973 for (; *fmt ; ++fmt) {
974 if (*fmt == '%')
975 break;
978 /* Return the current non-format string */
979 if (fmt != start || !*fmt)
980 return fmt - start;
982 /* Process flags */
983 spec->flags = 0;
985 while (1) { /* this also skips first '%' */
986 bool found = true;
988 ++fmt;
990 switch (*fmt) {
991 case '-': spec->flags |= LEFT; break;
992 case '+': spec->flags |= PLUS; break;
993 case ' ': spec->flags |= SPACE; break;
994 case '#': spec->flags |= SPECIAL; break;
995 case '0': spec->flags |= ZEROPAD; break;
996 default: found = false;
999 if (!found)
1000 break;
1003 /* get field width */
1004 spec->field_width = -1;
1006 if (isdigit(*fmt))
1007 spec->field_width = skip_atoi(&fmt);
1008 else if (*fmt == '*') {
1009 /* it's the next argument */
1010 spec->type = FORMAT_TYPE_WIDTH;
1011 return ++fmt - start;
1014 precision:
1015 /* get the precision */
1016 spec->precision = -1;
1017 if (*fmt == '.') {
1018 ++fmt;
1019 if (isdigit(*fmt)) {
1020 spec->precision = skip_atoi(&fmt);
1021 if (spec->precision < 0)
1022 spec->precision = 0;
1023 } else if (*fmt == '*') {
1024 /* it's the next argument */
1025 spec->type = FORMAT_TYPE_PRECISION;
1026 return ++fmt - start;
1030 qualifier:
1031 /* get the conversion qualifier */
1032 spec->qualifier = -1;
1033 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1034 TOLOWER(*fmt) == 'z' || *fmt == 't') {
1035 spec->qualifier = *fmt++;
1036 if (unlikely(spec->qualifier == *fmt)) {
1037 if (spec->qualifier == 'l') {
1038 spec->qualifier = 'L';
1039 ++fmt;
1040 } else if (spec->qualifier == 'h') {
1041 spec->qualifier = 'H';
1042 ++fmt;
1047 /* default base */
1048 spec->base = 10;
1049 switch (*fmt) {
1050 case 'c':
1051 spec->type = FORMAT_TYPE_CHAR;
1052 return ++fmt - start;
1054 case 's':
1055 spec->type = FORMAT_TYPE_STR;
1056 return ++fmt - start;
1058 case 'p':
1059 spec->type = FORMAT_TYPE_PTR;
1060 return fmt - start;
1061 /* skip alnum */
1063 case 'n':
1064 spec->type = FORMAT_TYPE_NRCHARS;
1065 return ++fmt - start;
1067 case '%':
1068 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1069 return ++fmt - start;
1071 /* integer number formats - set up the flags and "break" */
1072 case 'o':
1073 spec->base = 8;
1074 break;
1076 case 'x':
1077 spec->flags |= SMALL;
1079 case 'X':
1080 spec->base = 16;
1081 break;
1083 case 'd':
1084 case 'i':
1085 spec->flags |= SIGN;
1086 case 'u':
1087 break;
1089 default:
1090 spec->type = FORMAT_TYPE_INVALID;
1091 return fmt - start;
1094 if (spec->qualifier == 'L')
1095 spec->type = FORMAT_TYPE_LONG_LONG;
1096 else if (spec->qualifier == 'l') {
1097 if (spec->flags & SIGN)
1098 spec->type = FORMAT_TYPE_LONG;
1099 else
1100 spec->type = FORMAT_TYPE_ULONG;
1101 } else if (TOLOWER(spec->qualifier) == 'z') {
1102 spec->type = FORMAT_TYPE_SIZE_T;
1103 } else if (spec->qualifier == 't') {
1104 spec->type = FORMAT_TYPE_PTRDIFF;
1105 } else if (spec->qualifier == 'H') {
1106 if (spec->flags & SIGN)
1107 spec->type = FORMAT_TYPE_BYTE;
1108 else
1109 spec->type = FORMAT_TYPE_UBYTE;
1110 } else if (spec->qualifier == 'h') {
1111 if (spec->flags & SIGN)
1112 spec->type = FORMAT_TYPE_SHORT;
1113 else
1114 spec->type = FORMAT_TYPE_USHORT;
1115 } else {
1116 if (spec->flags & SIGN)
1117 spec->type = FORMAT_TYPE_INT;
1118 else
1119 spec->type = FORMAT_TYPE_UINT;
1122 return ++fmt - start;
1126 * vsnprintf - Format a string and place it in a buffer
1127 * @buf: The buffer to place the result into
1128 * @size: The size of the buffer, including the trailing null space
1129 * @fmt: The format string to use
1130 * @args: Arguments for the format string
1132 * This function follows C99 vsnprintf, but has some extensions:
1133 * %pS output the name of a text symbol with offset
1134 * %ps output the name of a text symbol without offset
1135 * %pF output the name of a function pointer with its offset
1136 * %pf output the name of a function pointer without its offset
1137 * %pR output the address range in a struct resource with decoded flags
1138 * %pr output the address range in a struct resource with raw flags
1139 * %pM output a 6-byte MAC address with colons
1140 * %pm output a 6-byte MAC address without colons
1141 * %pI4 print an IPv4 address without leading zeros
1142 * %pi4 print an IPv4 address with leading zeros
1143 * %pI6 print an IPv6 address with colons
1144 * %pi6 print an IPv6 address without colons
1145 * %pI6c print an IPv6 address as specified by
1146 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
1147 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1148 * case.
1149 * %n is ignored
1151 * The return value is the number of characters which would
1152 * be generated for the given input, excluding the trailing
1153 * '\0', as per ISO C99. If you want to have the exact
1154 * number of characters written into @buf as return value
1155 * (not including the trailing '\0'), use vscnprintf(). If the
1156 * return is greater than or equal to @size, the resulting
1157 * string is truncated.
1159 * Call this function if you are already dealing with a va_list.
1160 * You probably want snprintf() instead.
1162 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1164 unsigned long long num;
1165 char *str, *end;
1166 struct printf_spec spec = {0};
1168 /* Reject out-of-range values early. Large positive sizes are
1169 used for unknown buffer sizes. */
1170 if (WARN_ON_ONCE((int) size < 0))
1171 return 0;
1173 str = buf;
1174 end = buf + size;
1176 /* Make sure end is always >= buf */
1177 if (end < buf) {
1178 end = ((void *)-1);
1179 size = end - buf;
1182 while (*fmt) {
1183 const char *old_fmt = fmt;
1184 int read = format_decode(fmt, &spec);
1186 fmt += read;
1188 switch (spec.type) {
1189 case FORMAT_TYPE_NONE: {
1190 int copy = read;
1191 if (str < end) {
1192 if (copy > end - str)
1193 copy = end - str;
1194 memcpy(str, old_fmt, copy);
1196 str += read;
1197 break;
1200 case FORMAT_TYPE_WIDTH:
1201 spec.field_width = va_arg(args, int);
1202 break;
1204 case FORMAT_TYPE_PRECISION:
1205 spec.precision = va_arg(args, int);
1206 break;
1208 case FORMAT_TYPE_CHAR: {
1209 char c;
1211 if (!(spec.flags & LEFT)) {
1212 while (--spec.field_width > 0) {
1213 if (str < end)
1214 *str = ' ';
1215 ++str;
1219 c = (unsigned char) va_arg(args, int);
1220 if (str < end)
1221 *str = c;
1222 ++str;
1223 while (--spec.field_width > 0) {
1224 if (str < end)
1225 *str = ' ';
1226 ++str;
1228 break;
1231 case FORMAT_TYPE_STR:
1232 str = string(str, end, va_arg(args, char *), spec);
1233 break;
1235 case FORMAT_TYPE_PTR:
1236 str = pointer(fmt+1, str, end, va_arg(args, void *),
1237 spec);
1238 while (isalnum(*fmt))
1239 fmt++;
1240 break;
1242 case FORMAT_TYPE_PERCENT_CHAR:
1243 if (str < end)
1244 *str = '%';
1245 ++str;
1246 break;
1248 case FORMAT_TYPE_INVALID:
1249 if (str < end)
1250 *str = '%';
1251 ++str;
1252 break;
1254 case FORMAT_TYPE_NRCHARS: {
1255 u8 qualifier = spec.qualifier;
1257 if (qualifier == 'l') {
1258 long *ip = va_arg(args, long *);
1259 *ip = (str - buf);
1260 } else if (TOLOWER(qualifier) == 'z') {
1261 size_t *ip = va_arg(args, size_t *);
1262 *ip = (str - buf);
1263 } else {
1264 int *ip = va_arg(args, int *);
1265 *ip = (str - buf);
1267 break;
1270 default:
1271 switch (spec.type) {
1272 case FORMAT_TYPE_LONG_LONG:
1273 num = va_arg(args, long long);
1274 break;
1275 case FORMAT_TYPE_ULONG:
1276 num = va_arg(args, unsigned long);
1277 break;
1278 case FORMAT_TYPE_LONG:
1279 num = va_arg(args, long);
1280 break;
1281 case FORMAT_TYPE_SIZE_T:
1282 num = va_arg(args, size_t);
1283 break;
1284 case FORMAT_TYPE_PTRDIFF:
1285 num = va_arg(args, ptrdiff_t);
1286 break;
1287 case FORMAT_TYPE_UBYTE:
1288 num = (unsigned char) va_arg(args, int);
1289 break;
1290 case FORMAT_TYPE_BYTE:
1291 num = (signed char) va_arg(args, int);
1292 break;
1293 case FORMAT_TYPE_USHORT:
1294 num = (unsigned short) va_arg(args, int);
1295 break;
1296 case FORMAT_TYPE_SHORT:
1297 num = (short) va_arg(args, int);
1298 break;
1299 case FORMAT_TYPE_INT:
1300 num = (int) va_arg(args, int);
1301 break;
1302 default:
1303 num = va_arg(args, unsigned int);
1306 str = number(str, end, num, spec);
1310 if (size > 0) {
1311 if (str < end)
1312 *str = '\0';
1313 else
1314 end[-1] = '\0';
1317 /* the trailing null byte doesn't count towards the total */
1318 return str-buf;
1321 EXPORT_SYMBOL(vsnprintf);
1324 * vscnprintf - Format a string and place it in a buffer
1325 * @buf: The buffer to place the result into
1326 * @size: The size of the buffer, including the trailing null space
1327 * @fmt: The format string to use
1328 * @args: Arguments for the format string
1330 * The return value is the number of characters which have been written into
1331 * the @buf not including the trailing '\0'. If @size is == 0 the function
1332 * returns 0.
1334 * Call this function if you are already dealing with a va_list.
1335 * You probably want scnprintf() instead.
1337 * See the vsnprintf() documentation for format string extensions over C99.
1339 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1341 int i;
1343 i = vsnprintf(buf, size, fmt, args);
1345 if (likely(i < size))
1346 return i;
1347 if (size != 0)
1348 return size - 1;
1349 return 0;
1351 EXPORT_SYMBOL(vscnprintf);
1354 * snprintf - Format a string and place it in a buffer
1355 * @buf: The buffer to place the result into
1356 * @size: The size of the buffer, including the trailing null space
1357 * @fmt: The format string to use
1358 * @...: Arguments for the format string
1360 * The return value is the number of characters which would be
1361 * generated for the given input, excluding the trailing null,
1362 * as per ISO C99. If the return is greater than or equal to
1363 * @size, the resulting string is truncated.
1365 * See the vsnprintf() documentation for format string extensions over C99.
1367 int snprintf(char *buf, size_t size, const char *fmt, ...)
1369 va_list args;
1370 int i;
1372 va_start(args, fmt);
1373 i = vsnprintf(buf, size, fmt, args);
1374 va_end(args);
1376 return i;
1378 EXPORT_SYMBOL(snprintf);
1381 * scnprintf - Format a string and place it in a buffer
1382 * @buf: The buffer to place the result into
1383 * @size: The size of the buffer, including the trailing null space
1384 * @fmt: The format string to use
1385 * @...: Arguments for the format string
1387 * The return value is the number of characters written into @buf not including
1388 * the trailing '\0'. If @size is == 0 the function returns 0.
1391 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1393 va_list args;
1394 int i;
1396 va_start(args, fmt);
1397 i = vscnprintf(buf, size, fmt, args);
1398 va_end(args);
1400 return i;
1402 EXPORT_SYMBOL(scnprintf);
1405 * vsprintf - Format a string and place it in a buffer
1406 * @buf: The buffer to place the result into
1407 * @fmt: The format string to use
1408 * @args: Arguments for the format string
1410 * The function returns the number of characters written
1411 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1412 * buffer overflows.
1414 * Call this function if you are already dealing with a va_list.
1415 * You probably want sprintf() instead.
1417 * See the vsnprintf() documentation for format string extensions over C99.
1419 int vsprintf(char *buf, const char *fmt, va_list args)
1421 return vsnprintf(buf, INT_MAX, fmt, args);
1423 EXPORT_SYMBOL(vsprintf);
1426 * sprintf - Format a string and place it in a buffer
1427 * @buf: The buffer to place the result into
1428 * @fmt: The format string to use
1429 * @...: Arguments for the format string
1431 * The function returns the number of characters written
1432 * into @buf. Use snprintf() or scnprintf() in order to avoid
1433 * buffer overflows.
1435 * See the vsnprintf() documentation for format string extensions over C99.
1437 int sprintf(char *buf, const char *fmt, ...)
1439 va_list args;
1440 int i;
1442 va_start(args, fmt);
1443 i = vsnprintf(buf, INT_MAX, fmt, args);
1444 va_end(args);
1446 return i;
1448 EXPORT_SYMBOL(sprintf);
1450 #ifdef CONFIG_BINARY_PRINTF
1452 * bprintf service:
1453 * vbin_printf() - VA arguments to binary data
1454 * bstr_printf() - Binary data to text string
1458 * vbin_printf - Parse a format string and place args' binary value in a buffer
1459 * @bin_buf: The buffer to place args' binary value
1460 * @size: The size of the buffer(by words(32bits), not characters)
1461 * @fmt: The format string to use
1462 * @args: Arguments for the format string
1464 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1465 * is skiped.
1467 * The return value is the number of words(32bits) which would be generated for
1468 * the given input.
1470 * NOTE:
1471 * If the return value is greater than @size, the resulting bin_buf is NOT
1472 * valid for bstr_printf().
1474 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1476 struct printf_spec spec = {0};
1477 char *str, *end;
1479 str = (char *)bin_buf;
1480 end = (char *)(bin_buf + size);
1482 #define save_arg(type) \
1483 do { \
1484 if (sizeof(type) == 8) { \
1485 unsigned long long value; \
1486 str = PTR_ALIGN(str, sizeof(u32)); \
1487 value = va_arg(args, unsigned long long); \
1488 if (str + sizeof(type) <= end) { \
1489 *(u32 *)str = *(u32 *)&value; \
1490 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1492 } else { \
1493 unsigned long value; \
1494 str = PTR_ALIGN(str, sizeof(type)); \
1495 value = va_arg(args, int); \
1496 if (str + sizeof(type) <= end) \
1497 *(typeof(type) *)str = (type)value; \
1499 str += sizeof(type); \
1500 } while (0)
1502 while (*fmt) {
1503 int read = format_decode(fmt, &spec);
1505 fmt += read;
1507 switch (spec.type) {
1508 case FORMAT_TYPE_NONE:
1509 case FORMAT_TYPE_INVALID:
1510 case FORMAT_TYPE_PERCENT_CHAR:
1511 break;
1513 case FORMAT_TYPE_WIDTH:
1514 case FORMAT_TYPE_PRECISION:
1515 save_arg(int);
1516 break;
1518 case FORMAT_TYPE_CHAR:
1519 save_arg(char);
1520 break;
1522 case FORMAT_TYPE_STR: {
1523 const char *save_str = va_arg(args, char *);
1524 size_t len;
1526 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1527 || (unsigned long)save_str < PAGE_SIZE)
1528 save_str = "(null)";
1529 len = strlen(save_str) + 1;
1530 if (str + len < end)
1531 memcpy(str, save_str, len);
1532 str += len;
1533 break;
1536 case FORMAT_TYPE_PTR:
1537 save_arg(void *);
1538 /* skip all alphanumeric pointer suffixes */
1539 while (isalnum(*fmt))
1540 fmt++;
1541 break;
1543 case FORMAT_TYPE_NRCHARS: {
1544 /* skip %n 's argument */
1545 u8 qualifier = spec.qualifier;
1546 void *skip_arg;
1547 if (qualifier == 'l')
1548 skip_arg = va_arg(args, long *);
1549 else if (TOLOWER(qualifier) == 'z')
1550 skip_arg = va_arg(args, size_t *);
1551 else
1552 skip_arg = va_arg(args, int *);
1553 break;
1556 default:
1557 switch (spec.type) {
1559 case FORMAT_TYPE_LONG_LONG:
1560 save_arg(long long);
1561 break;
1562 case FORMAT_TYPE_ULONG:
1563 case FORMAT_TYPE_LONG:
1564 save_arg(unsigned long);
1565 break;
1566 case FORMAT_TYPE_SIZE_T:
1567 save_arg(size_t);
1568 break;
1569 case FORMAT_TYPE_PTRDIFF:
1570 save_arg(ptrdiff_t);
1571 break;
1572 case FORMAT_TYPE_UBYTE:
1573 case FORMAT_TYPE_BYTE:
1574 save_arg(char);
1575 break;
1576 case FORMAT_TYPE_USHORT:
1577 case FORMAT_TYPE_SHORT:
1578 save_arg(short);
1579 break;
1580 default:
1581 save_arg(int);
1586 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1587 #undef save_arg
1589 EXPORT_SYMBOL_GPL(vbin_printf);
1592 * bstr_printf - Format a string from binary arguments and place it in a buffer
1593 * @buf: The buffer to place the result into
1594 * @size: The size of the buffer, including the trailing null space
1595 * @fmt: The format string to use
1596 * @bin_buf: Binary arguments for the format string
1598 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1599 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1600 * a binary buffer that generated by vbin_printf.
1602 * The format follows C99 vsnprintf, but has some extensions:
1603 * see vsnprintf comment for details.
1605 * The return value is the number of characters which would
1606 * be generated for the given input, excluding the trailing
1607 * '\0', as per ISO C99. If you want to have the exact
1608 * number of characters written into @buf as return value
1609 * (not including the trailing '\0'), use vscnprintf(). If the
1610 * return is greater than or equal to @size, the resulting
1611 * string is truncated.
1613 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1615 struct printf_spec spec = {0};
1616 char *str, *end;
1617 const char *args = (const char *)bin_buf;
1619 if (WARN_ON_ONCE((int) size < 0))
1620 return 0;
1622 str = buf;
1623 end = buf + size;
1625 #define get_arg(type) \
1626 ({ \
1627 typeof(type) value; \
1628 if (sizeof(type) == 8) { \
1629 args = PTR_ALIGN(args, sizeof(u32)); \
1630 *(u32 *)&value = *(u32 *)args; \
1631 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1632 } else { \
1633 args = PTR_ALIGN(args, sizeof(type)); \
1634 value = *(typeof(type) *)args; \
1636 args += sizeof(type); \
1637 value; \
1640 /* Make sure end is always >= buf */
1641 if (end < buf) {
1642 end = ((void *)-1);
1643 size = end - buf;
1646 while (*fmt) {
1647 const char *old_fmt = fmt;
1648 int read = format_decode(fmt, &spec);
1650 fmt += read;
1652 switch (spec.type) {
1653 case FORMAT_TYPE_NONE: {
1654 int copy = read;
1655 if (str < end) {
1656 if (copy > end - str)
1657 copy = end - str;
1658 memcpy(str, old_fmt, copy);
1660 str += read;
1661 break;
1664 case FORMAT_TYPE_WIDTH:
1665 spec.field_width = get_arg(int);
1666 break;
1668 case FORMAT_TYPE_PRECISION:
1669 spec.precision = get_arg(int);
1670 break;
1672 case FORMAT_TYPE_CHAR: {
1673 char c;
1675 if (!(spec.flags & LEFT)) {
1676 while (--spec.field_width > 0) {
1677 if (str < end)
1678 *str = ' ';
1679 ++str;
1682 c = (unsigned char) get_arg(char);
1683 if (str < end)
1684 *str = c;
1685 ++str;
1686 while (--spec.field_width > 0) {
1687 if (str < end)
1688 *str = ' ';
1689 ++str;
1691 break;
1694 case FORMAT_TYPE_STR: {
1695 const char *str_arg = args;
1696 args += strlen(str_arg) + 1;
1697 str = string(str, end, (char *)str_arg, spec);
1698 break;
1701 case FORMAT_TYPE_PTR:
1702 str = pointer(fmt+1, str, end, get_arg(void *), spec);
1703 while (isalnum(*fmt))
1704 fmt++;
1705 break;
1707 case FORMAT_TYPE_PERCENT_CHAR:
1708 case FORMAT_TYPE_INVALID:
1709 if (str < end)
1710 *str = '%';
1711 ++str;
1712 break;
1714 case FORMAT_TYPE_NRCHARS:
1715 /* skip */
1716 break;
1718 default: {
1719 unsigned long long num;
1721 switch (spec.type) {
1723 case FORMAT_TYPE_LONG_LONG:
1724 num = get_arg(long long);
1725 break;
1726 case FORMAT_TYPE_ULONG:
1727 case FORMAT_TYPE_LONG:
1728 num = get_arg(unsigned long);
1729 break;
1730 case FORMAT_TYPE_SIZE_T:
1731 num = get_arg(size_t);
1732 break;
1733 case FORMAT_TYPE_PTRDIFF:
1734 num = get_arg(ptrdiff_t);
1735 break;
1736 case FORMAT_TYPE_UBYTE:
1737 num = get_arg(unsigned char);
1738 break;
1739 case FORMAT_TYPE_BYTE:
1740 num = get_arg(signed char);
1741 break;
1742 case FORMAT_TYPE_USHORT:
1743 num = get_arg(unsigned short);
1744 break;
1745 case FORMAT_TYPE_SHORT:
1746 num = get_arg(short);
1747 break;
1748 case FORMAT_TYPE_UINT:
1749 num = get_arg(unsigned int);
1750 break;
1751 default:
1752 num = get_arg(int);
1755 str = number(str, end, num, spec);
1756 } /* default: */
1757 } /* switch(spec.type) */
1758 } /* while(*fmt) */
1760 if (size > 0) {
1761 if (str < end)
1762 *str = '\0';
1763 else
1764 end[-1] = '\0';
1767 #undef get_arg
1769 /* the trailing null byte doesn't count towards the total */
1770 return str - buf;
1772 EXPORT_SYMBOL_GPL(bstr_printf);
1775 * bprintf - Parse a format string and place args' binary value in a buffer
1776 * @bin_buf: The buffer to place args' binary value
1777 * @size: The size of the buffer(by words(32bits), not characters)
1778 * @fmt: The format string to use
1779 * @...: Arguments for the format string
1781 * The function returns the number of words(u32) written
1782 * into @bin_buf.
1784 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1786 va_list args;
1787 int ret;
1789 va_start(args, fmt);
1790 ret = vbin_printf(bin_buf, size, fmt, args);
1791 va_end(args);
1793 return ret;
1795 EXPORT_SYMBOL_GPL(bprintf);
1797 #endif /* CONFIG_BINARY_PRINTF */
1800 * vsscanf - Unformat a buffer into a list of arguments
1801 * @buf: input buffer
1802 * @fmt: format of buffer
1803 * @args: arguments
1805 int vsscanf(const char *buf, const char *fmt, va_list args)
1807 const char *str = buf;
1808 char *next;
1809 char digit;
1810 int num = 0;
1811 u8 qualifier;
1812 u8 base;
1813 s16 field_width;
1814 bool is_sign;
1816 while (*fmt && *str) {
1817 /* skip any white space in format */
1818 /* white space in format matchs any amount of
1819 * white space, including none, in the input.
1821 if (isspace(*fmt)) {
1822 fmt = skip_spaces(++fmt);
1823 str = skip_spaces(str);
1826 /* anything that is not a conversion must match exactly */
1827 if (*fmt != '%' && *fmt) {
1828 if (*fmt++ != *str++)
1829 break;
1830 continue;
1833 if (!*fmt)
1834 break;
1835 ++fmt;
1837 /* skip this conversion.
1838 * advance both strings to next white space
1840 if (*fmt == '*') {
1841 while (!isspace(*fmt) && *fmt != '%' && *fmt)
1842 fmt++;
1843 while (!isspace(*str) && *str)
1844 str++;
1845 continue;
1848 /* get field width */
1849 field_width = -1;
1850 if (isdigit(*fmt))
1851 field_width = skip_atoi(&fmt);
1853 /* get conversion qualifier */
1854 qualifier = -1;
1855 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1856 TOLOWER(*fmt) == 'z') {
1857 qualifier = *fmt++;
1858 if (unlikely(qualifier == *fmt)) {
1859 if (qualifier == 'h') {
1860 qualifier = 'H';
1861 fmt++;
1862 } else if (qualifier == 'l') {
1863 qualifier = 'L';
1864 fmt++;
1869 if (!*fmt || !*str)
1870 break;
1872 base = 10;
1873 is_sign = 0;
1875 switch (*fmt++) {
1876 case 'c':
1878 char *s = (char *)va_arg(args, char*);
1879 if (field_width == -1)
1880 field_width = 1;
1881 do {
1882 *s++ = *str++;
1883 } while (--field_width > 0 && *str);
1884 num++;
1886 continue;
1887 case 's':
1889 char *s = (char *)va_arg(args, char *);
1890 if (field_width == -1)
1891 field_width = SHRT_MAX;
1892 /* first, skip leading white space in buffer */
1893 str = skip_spaces(str);
1895 /* now copy until next white space */
1896 while (*str && !isspace(*str) && field_width--)
1897 *s++ = *str++;
1898 *s = '\0';
1899 num++;
1901 continue;
1902 case 'n':
1903 /* return number of characters read so far */
1905 int *i = (int *)va_arg(args, int*);
1906 *i = str - buf;
1908 continue;
1909 case 'o':
1910 base = 8;
1911 break;
1912 case 'x':
1913 case 'X':
1914 base = 16;
1915 break;
1916 case 'i':
1917 base = 0;
1918 case 'd':
1919 is_sign = 1;
1920 case 'u':
1921 break;
1922 case '%':
1923 /* looking for '%' in str */
1924 if (*str++ != '%')
1925 return num;
1926 continue;
1927 default:
1928 /* invalid format; stop here */
1929 return num;
1932 /* have some sort of integer conversion.
1933 * first, skip white space in buffer.
1935 str = skip_spaces(str);
1937 digit = *str;
1938 if (is_sign && digit == '-')
1939 digit = *(str + 1);
1941 if (!digit
1942 || (base == 16 && !isxdigit(digit))
1943 || (base == 10 && !isdigit(digit))
1944 || (base == 8 && (!isdigit(digit) || digit > '7'))
1945 || (base == 0 && !isdigit(digit)))
1946 break;
1948 switch (qualifier) {
1949 case 'H': /* that's 'hh' in format */
1950 if (is_sign) {
1951 signed char *s = (signed char *)va_arg(args, signed char *);
1952 *s = (signed char)simple_strtol(str, &next, base);
1953 } else {
1954 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1955 *s = (unsigned char)simple_strtoul(str, &next, base);
1957 break;
1958 case 'h':
1959 if (is_sign) {
1960 short *s = (short *)va_arg(args, short *);
1961 *s = (short)simple_strtol(str, &next, base);
1962 } else {
1963 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1964 *s = (unsigned short)simple_strtoul(str, &next, base);
1966 break;
1967 case 'l':
1968 if (is_sign) {
1969 long *l = (long *)va_arg(args, long *);
1970 *l = simple_strtol(str, &next, base);
1971 } else {
1972 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1973 *l = simple_strtoul(str, &next, base);
1975 break;
1976 case 'L':
1977 if (is_sign) {
1978 long long *l = (long long *)va_arg(args, long long *);
1979 *l = simple_strtoll(str, &next, base);
1980 } else {
1981 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1982 *l = simple_strtoull(str, &next, base);
1984 break;
1985 case 'Z':
1986 case 'z':
1988 size_t *s = (size_t *)va_arg(args, size_t *);
1989 *s = (size_t)simple_strtoul(str, &next, base);
1991 break;
1992 default:
1993 if (is_sign) {
1994 int *i = (int *)va_arg(args, int *);
1995 *i = (int)simple_strtol(str, &next, base);
1996 } else {
1997 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
1998 *i = (unsigned int)simple_strtoul(str, &next, base);
2000 break;
2002 num++;
2004 if (!next)
2005 break;
2006 str = next;
2010 * Now we've come all the way through so either the input string or the
2011 * format ended. In the former case, there can be a %n at the current
2012 * position in the format that needs to be filled.
2014 if (*fmt == '%' && *(fmt + 1) == 'n') {
2015 int *p = (int *)va_arg(args, int *);
2016 *p = str - buf;
2019 return num;
2021 EXPORT_SYMBOL(vsscanf);
2024 * sscanf - Unformat a buffer into a list of arguments
2025 * @buf: input buffer
2026 * @fmt: formatting of buffer
2027 * @...: resulting arguments
2029 int sscanf(const char *buf, const char *fmt, ...)
2031 va_list args;
2032 int i;
2034 va_start(args, fmt);
2035 i = vsscanf(buf, fmt, args);
2036 va_end(args);
2038 return i;
2040 EXPORT_SYMBOL(sscanf);