lib/vsprintf.c

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