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 EXPORT_SYMBOL(simple_strtoll);
 122
 123 /**
 124  * strict_strtoul - convert a string to an unsigned long strictly
 125  * @cp: The string to be converted
 126  * @base: The number base to use
 127  * @res: The converted result value
 128  *
 129  * strict_strtoul converts a string to an unsigned long only if the
 130  * string is really an unsigned long string, any string containing
 131  * any invalid char at the tail will be rejected and -EINVAL is returned,
 132  * only a newline char at the tail is acceptible because people generally
 133  * change a module parameter in the following way:
 134  *
 135  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 136  *
 137  * echo will append a newline to the tail.
 138  *
 139  * It returns 0 if conversion is successful and *res is set to the converted
 140  * value, otherwise it returns -EINVAL and *res is set to 0.
 141  *
 142  * simple_strtoul just ignores the successive invalid characters and
 143  * return the converted value of prefix part of the string.
 144  */
 145 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
 146 {
 147         char *tail;
 148         unsigned long val;
 149
 150         *res = 0;
 151         if (!*cp)
 152                 return -EINVAL;
 153
 154         val = simple_strtoul(cp, &tail, base);
 155         if (tail == cp)
 156                 return -EINVAL;
 157
 158         if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
 159                 *res = val;
 160                 return 0;
 161         }
 162
 163         return -EINVAL;
 164 }
 165 EXPORT_SYMBOL(strict_strtoul);
 166
 167 /**
 168  * strict_strtol - convert a string to a long strictly
 169  * @cp: The string to be converted
 170  * @base: The number base to use
 171  * @res: The converted result value
 172  *
 173  * strict_strtol is similiar to strict_strtoul, but it allows the first
 174  * character of a string is '-'.
 175  *
 176  * It returns 0 if conversion is successful and *res is set to the converted
 177  * value, otherwise it returns -EINVAL and *res is set to 0.
 178  */
 179 int strict_strtol(const char *cp, unsigned int base, long *res)
 180 {
 181         int ret;
 182         if (*cp == '-') {
 183                 ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
 184                 if (!ret)
 185                         *res = -(*res);
 186         } else {
 187                 ret = strict_strtoul(cp, base, (unsigned long *)res);
 188         }
 189
 190         return ret;
 191 }
 192 EXPORT_SYMBOL(strict_strtol);
 193
 194 /**
 195  * strict_strtoull - convert a string to an unsigned long long strictly
 196  * @cp: The string to be converted
 197  * @base: The number base to use
 198  * @res: The converted result value
 199  *
 200  * strict_strtoull converts a string to an unsigned long long only if the
 201  * string is really an unsigned long long string, any string containing
 202  * any invalid char at the tail will be rejected and -EINVAL is returned,
 203  * only a newline char at the tail is acceptible because people generally
 204  * change a module parameter in the following way:
 205  *
 206  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 207  *
 208  * echo will append a newline to the tail of the string.
 209  *
 210  * It returns 0 if conversion is successful and *res is set to the converted
 211  * value, otherwise it returns -EINVAL and *res is set to 0.
 212  *
 213  * simple_strtoull just ignores the successive invalid characters and
 214  * return the converted value of prefix part of the string.
 215  */
 216 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
 217 {
 218         char *tail;
 219         unsigned long long val;
 220
 221         *res = 0;
 222         if (!*cp)
 223                 return -EINVAL;
 224
 225         val = simple_strtoull(cp, &tail, base);
 226         if (tail == cp)
 227                 return -EINVAL;
 228         if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
 229                 *res = val;
 230                 return 0;
 231         }
 232
 233         return -EINVAL;
 234 }
 235 EXPORT_SYMBOL(strict_strtoull);
 236
 237 /**
 238  * strict_strtoll - convert a string to a long long strictly
 239  * @cp: The string to be converted
 240  * @base: The number base to use
 241  * @res: The converted result value
 242  *
 243  * strict_strtoll is similiar to strict_strtoull, but it allows the first
 244  * character of a string is '-'.
 245  *
 246  * It returns 0 if conversion is successful and *res is set to the converted
 247  * value, otherwise it returns -EINVAL and *res is set to 0.
 248  */
 249 int strict_strtoll(const char *cp, unsigned int base, long long *res)
 250 {
 251         int ret;
 252         if (*cp == '-') {
 253                 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
 254                 if (!ret)
 255                         *res = -(*res);
 256         } else {
 257                 ret = strict_strtoull(cp, base, (unsigned long long *)res);
 258         }
 259
 260         return ret;
 261 }
 262 EXPORT_SYMBOL(strict_strtoll);
 263
 264 static noinline_for_stack
 265 int skip_atoi(const char **s)
 266 {
 267         int i = 0;
 268
 269         while (isdigit(**s))
 270                 i = i*10 + *((*s)++) - '0';
 271
 272         return i;
 273 }
 274
 275 /* Decimal conversion is by far the most typical, and is used
 276  * for /proc and /sys data. This directly impacts e.g. top performance
 277  * with many processes running. We optimize it for speed
 278  * using code from
 279  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 280  * (with permission from the author, Douglas W. Jones). */
 281
 282 /* Formats correctly any integer in [0,99999].
 283  * Outputs from one to five digits depending on input.
 284  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
 285 static noinline_for_stack
 286 char *put_dec_trunc(char *buf, unsigned q)
 287 {
 288         unsigned d3, d2, d1, d0;
 289         d1 = (q>>4) & 0xf;
 290         d2 = (q>>8) & 0xf;
 291         d3 = (q>>12);
 292
 293         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 294         q = (d0 * 0xcd) >> 11;
 295         d0 = d0 - 10*q;
 296         *buf++ = d0 + '0'; /* least significant digit */
 297         d1 = q + 9*d3 + 5*d2 + d1;
 298         if (d1 != 0) {
 299                 q = (d1 * 0xcd) >> 11;
 300                 d1 = d1 - 10*q;
 301                 *buf++ = d1 + '0'; /* next digit */
 302
 303                 d2 = q + 2*d2;
 304                 if ((d2 != 0) || (d3 != 0)) {
 305                         q = (d2 * 0xd) >> 7;
 306                         d2 = d2 - 10*q;
 307                         *buf++ = d2 + '0'; /* next digit */
 308
 309                         d3 = q + 4*d3;
 310                         if (d3 != 0) {
 311                                 q = (d3 * 0xcd) >> 11;
 312                                 d3 = d3 - 10*q;
 313                                 *buf++ = d3 + '0';  /* next digit */
 314                                 if (q != 0)
 315                                         *buf++ = q + '0'; /* most sign. digit */
 316                         }
 317                 }
 318         }
 319
 320         return buf;
 321 }
 322 /* Same with if's removed. Always emits five digits */
 323 static noinline_for_stack
 324 char *put_dec_full(char *buf, unsigned q)
 325 {
 326         /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
 327         /* but anyway, gcc produces better code with full-sized ints */
 328         unsigned d3, d2, d1, d0;
 329         d1 = (q>>4) & 0xf;
 330         d2 = (q>>8) & 0xf;
 331         d3 = (q>>12);
 332
 333         /*
 334          * Possible ways to approx. divide by 10
 335          * gcc -O2 replaces multiply with shifts and adds
 336          * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
 337          * (x * 0x67) >> 10:  1100111
 338          * (x * 0x34) >> 9:    110100 - same
 339          * (x * 0x1a) >> 8:     11010 - same
 340          * (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
 341          */
 342         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 343         q = (d0 * 0xcd) >> 11;
 344         d0 = d0 - 10*q;
 345         *buf++ = d0 + '0';
 346         d1 = q + 9*d3 + 5*d2 + d1;
 347                 q = (d1 * 0xcd) >> 11;
 348                 d1 = d1 - 10*q;
 349                 *buf++ = d1 + '0';
 350
 351                 d2 = q + 2*d2;
 352                         q = (d2 * 0xd) >> 7;
 353                         d2 = d2 - 10*q;
 354                         *buf++ = d2 + '0';
 355
 356                         d3 = q + 4*d3;
 357                                 q = (d3 * 0xcd) >> 11; /* - shorter code */
 358                                 /* q = (d3 * 0x67) >> 10; - would also work */
 359                                 d3 = d3 - 10*q;
 360                                 *buf++ = d3 + '0';
 361                                         *buf++ = q + '0';
 362
 363         return buf;
 364 }
 365 /* No inlining helps gcc to use registers better */
 366 static noinline_for_stack
 367 char *put_dec(char *buf, unsigned long long num)
 368 {
 369         while (1) {
 370                 unsigned rem;
 371                 if (num < 100000)
 372                         return put_dec_trunc(buf, num);
 373                 rem = do_div(num, 100000);
 374                 buf = put_dec_full(buf, rem);
 375         }
 376 }
 377
 378 #define ZEROPAD 1               /* pad with zero */
 379 #define SIGN    2               /* unsigned/signed long */
 380 #define PLUS    4               /* show plus */
 381 #define SPACE   8               /* space if plus */
 382 #define LEFT    16              /* left justified */
 383 #define SMALL   32              /* use lowercase in hex (must be 32 == 0x20) */
 384 #define SPECIAL 64              /* prefix hex with "0x", octal with "0" */
 385
 386 enum format_type {
 387         FORMAT_TYPE_NONE, /* Just a string part */
 388         FORMAT_TYPE_WIDTH,
 389         FORMAT_TYPE_PRECISION,
 390         FORMAT_TYPE_CHAR,
 391         FORMAT_TYPE_STR,
 392         FORMAT_TYPE_PTR,
 393         FORMAT_TYPE_PERCENT_CHAR,
 394         FORMAT_TYPE_INVALID,
 395         FORMAT_TYPE_LONG_LONG,
 396         FORMAT_TYPE_ULONG,
 397         FORMAT_TYPE_LONG,
 398         FORMAT_TYPE_UBYTE,
 399         FORMAT_TYPE_BYTE,
 400         FORMAT_TYPE_USHORT,
 401         FORMAT_TYPE_SHORT,
 402         FORMAT_TYPE_UINT,
 403         FORMAT_TYPE_INT,
 404         FORMAT_TYPE_NRCHARS,
 405         FORMAT_TYPE_SIZE_T,
 406         FORMAT_TYPE_PTRDIFF
 407 };
 408
 409 struct printf_spec {
 410         u8      type;           /* format_type enum */
 411         u8      flags;          /* flags to number() */
 412         u8      base;           /* number base, 8, 10 or 16 only */
 413         u8      qualifier;      /* number qualifier, one of 'hHlLtzZ' */
 414         s16     field_width;    /* width of output field */
 415         s16     precision;      /* # of digits/chars */
 416 };
 417
 418 static noinline_for_stack
 419 char *number(char *buf, char *end, unsigned long long num,
 420              struct printf_spec spec)
 421 {
 422         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 423         static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 424
 425         char tmp[66];
 426         char sign;
 427         char locase;
 428         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 429         int i;
 430
 431         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 432          * produces same digits or (maybe lowercased) letters */
 433         locase = (spec.flags & SMALL);
 434         if (spec.flags & LEFT)
 435                 spec.flags &= ~ZEROPAD;
 436         sign = 0;
 437         if (spec.flags & SIGN) {
 438                 if ((signed long long)num < 0) {
 439                         sign = '-';
 440                         num = -(signed long long)num;
 441                         spec.field_width--;
 442                 } else if (spec.flags & PLUS) {
 443                         sign = '+';
 444                         spec.field_width--;
 445                 } else if (spec.flags & SPACE) {
 446                         sign = ' ';
 447                         spec.field_width--;
 448                 }
 449         }
 450         if (need_pfx) {
 451                 spec.field_width--;
 452                 if (spec.base == 16)
 453                         spec.field_width--;
 454         }
 455
 456         /* generate full string in tmp[], in reverse order */
 457         i = 0;
 458         if (num == 0)
 459                 tmp[i++] = '0';
 460         /* Generic code, for any base:
 461         else do {
 462                 tmp[i++] = (digits[do_div(num,base)] | locase);
 463         } while (num != 0);
 464         */
 465         else if (spec.base != 10) { /* 8 or 16 */
 466                 int mask = spec.base - 1;
 467                 int shift = 3;
 468
 469                 if (spec.base == 16)
 470                         shift = 4;
 471                 do {
 472                         tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 473                         num >>= shift;
 474                 } while (num);
 475         } else { /* base 10 */
 476                 i = put_dec(tmp, num) - tmp;
 477         }
 478
 479         /* printing 100 using %2d gives "100", not "00" */
 480         if (i > spec.precision)
 481                 spec.precision = i;
 482         /* leading space padding */
 483         spec.field_width -= spec.precision;
 484         if (!(spec.flags & (ZEROPAD+LEFT))) {
 485                 while (--spec.field_width >= 0) {
 486                         if (buf < end)
 487                                 *buf = ' ';
 488                         ++buf;
 489                 }
 490         }
 491         /* sign */
 492         if (sign) {
 493                 if (buf < end)
 494                         *buf = sign;
 495                 ++buf;
 496         }
 497         /* "0x" / "0" prefix */
 498         if (need_pfx) {
 499                 if (buf < end)
 500                         *buf = '0';
 501                 ++buf;
 502                 if (spec.base == 16) {
 503                         if (buf < end)
 504                                 *buf = ('X' | locase);
 505                         ++buf;
 506                 }
 507         }
 508         /* zero or space padding */
 509         if (!(spec.flags & LEFT)) {
 510                 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
 511                 while (--spec.field_width >= 0) {
 512                         if (buf < end)
 513                                 *buf = c;
 514                         ++buf;
 515                 }
 516         }
 517         /* hmm even more zero padding? */
 518         while (i <= --spec.precision) {
 519                 if (buf < end)
 520                         *buf = '0';
 521                 ++buf;
 522         }
 523         /* actual digits of result */
 524         while (--i >= 0) {
 525                 if (buf < end)
 526                         *buf = tmp[i];
 527                 ++buf;
 528         }
 529         /* trailing space padding */
 530         while (--spec.field_width >= 0) {
 531                 if (buf < end)
 532                         *buf = ' ';
 533                 ++buf;
 534         }
 535
 536         return buf;
 537 }
 538
 539 static noinline_for_stack
 540 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
 541 {
 542         int len, i;
 543
 544         if ((unsigned long)s < PAGE_SIZE)
 545                 s = "(null)";
 546
 547         len = strnlen(s, spec.precision);
 548
 549         if (!(spec.flags & LEFT)) {
 550                 while (len < spec.field_width--) {
 551                         if (buf < end)
 552                                 *buf = ' ';
 553                         ++buf;
 554                 }
 555         }
 556         for (i = 0; i < len; ++i) {
 557                 if (buf < end)
 558                         *buf = *s;
 559                 ++buf; ++s;
 560         }
 561         while (len < spec.field_width--) {
 562                 if (buf < end)
 563                         *buf = ' ';
 564                 ++buf;
 565         }
 566
 567         return buf;
 568 }
 569
 570 static noinline_for_stack
 571 char *symbol_string(char *buf, char *end, void *ptr,
 572                     struct printf_spec spec, char ext)
 573 {
 574         unsigned long value = (unsigned long) ptr;
 575 #ifdef CONFIG_KALLSYMS
 576         char sym[KSYM_SYMBOL_LEN];
 577         if (ext != 'f' && ext != 's')
 578                 sprint_symbol(sym, value);
 579         else
 580                 kallsyms_lookup(value, NULL, NULL, NULL, sym);
 581
 582         return string(buf, end, sym, spec);
 583 #else
 584         spec.field_width = 2 * sizeof(void *);
 585         spec.flags |= SPECIAL | SMALL | ZEROPAD;
 586         spec.base = 16;
 587
 588         return number(buf, end, value, spec);
 589 #endif
 590 }
 591
 592 static noinline_for_stack
 593 char *resource_string(char *buf, char *end, struct resource *res,
 594                       struct printf_spec spec, const char *fmt)
 595 {
 596 #ifndef IO_RSRC_PRINTK_SIZE
 597 #define IO_RSRC_PRINTK_SIZE     6
 598 #endif
 599
 600 #ifndef MEM_RSRC_PRINTK_SIZE
 601 #define MEM_RSRC_PRINTK_SIZE    10
 602 #endif
 603         static const struct printf_spec io_spec = {
 604                 .base = 16,
 605                 .field_width = IO_RSRC_PRINTK_SIZE,
 606                 .precision = -1,
 607                 .flags = SPECIAL | SMALL | ZEROPAD,
 608         };
 609         static const struct printf_spec mem_spec = {
 610                 .base = 16,
 611                 .field_width = MEM_RSRC_PRINTK_SIZE,
 612                 .precision = -1,
 613                 .flags = SPECIAL | SMALL | ZEROPAD,
 614         };
 615         static const struct printf_spec bus_spec = {
 616                 .base = 16,
 617                 .field_width = 2,
 618                 .precision = -1,
 619                 .flags = SMALL | ZEROPAD,
 620         };
 621         static const struct printf_spec dec_spec = {
 622                 .base = 10,
 623                 .precision = -1,
 624                 .flags = 0,
 625         };
 626         static const struct printf_spec str_spec = {
 627                 .field_width = -1,
 628                 .precision = 10,
 629                 .flags = LEFT,
 630         };
 631         static const struct printf_spec flag_spec = {
 632                 .base = 16,
 633                 .precision = -1,
 634                 .flags = SPECIAL | SMALL,
 635         };
 636
 637         /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 638          * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 639 #define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
 640 #define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
 641 #define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref window disabled]")
 642 #define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
 643         char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 644                      2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 645
 646         char *p = sym, *pend = sym + sizeof(sym);
 647         int decode = (fmt[0] == 'R') ? 1 : 0;
 648         const struct printf_spec *specp;
 649
 650         *p++ = '[';
 651         if (res->flags & IORESOURCE_IO) {
 652                 p = string(p, pend, "io  ", str_spec);
 653                 specp = &io_spec;
 654         } else if (res->flags & IORESOURCE_MEM) {
 655                 p = string(p, pend, "mem ", str_spec);
 656                 specp = &mem_spec;
 657         } else if (res->flags & IORESOURCE_IRQ) {
 658                 p = string(p, pend, "irq ", str_spec);
 659                 specp = &dec_spec;
 660         } else if (res->flags & IORESOURCE_DMA) {
 661                 p = string(p, pend, "dma ", str_spec);
 662                 specp = &dec_spec;
 663         } else if (res->flags & IORESOURCE_BUS) {
 664                 p = string(p, pend, "bus ", str_spec);
 665                 specp = &bus_spec;
 666         } else {
 667                 p = string(p, pend, "??? ", str_spec);
 668                 specp = &mem_spec;
 669                 decode = 0;
 670         }
 671         p = number(p, pend, res->start, *specp);
 672         if (res->start != res->end) {
 673                 *p++ = '-';
 674                 p = number(p, pend, res->end, *specp);
 675         }
 676         if (decode) {
 677                 if (res->flags & IORESOURCE_MEM_64)
 678                         p = string(p, pend, " 64bit", str_spec);
 679                 if (res->flags & IORESOURCE_PREFETCH)
 680                         p = string(p, pend, " pref", str_spec);
 681                 if (res->flags & IORESOURCE_WINDOW)
 682                         p = string(p, pend, " window", str_spec);
 683                 if (res->flags & IORESOURCE_DISABLED)
 684                         p = string(p, pend, " disabled", str_spec);
 685         } else {
 686                 p = string(p, pend, " flags ", str_spec);
 687                 p = number(p, pend, res->flags, flag_spec);
 688         }
 689         *p++ = ']';
 690         *p = '\0';
 691
 692         return string(buf, end, sym, spec);
 693 }
 694
 695 static noinline_for_stack
 696 char *mac_address_string(char *buf, char *end, u8 *addr,
 697                          struct printf_spec spec, const char *fmt)
 698 {
 699         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
 700         char *p = mac_addr;
 701         int i;
 702         char separator;
 703
 704         if (fmt[1] == 'F') {            /* FDDI canonical format */
 705                 separator = '-';
 706         } else {
 707                 separator = ':';
 708         }
 709
 710         for (i = 0; i < 6; i++) {
 711                 p = pack_hex_byte(p, addr[i]);
 712                 if (fmt[0] == 'M' && i != 5)
 713                         *p++ = separator;
 714         }
 715         *p = '\0';
 716
 717         return string(buf, end, mac_addr, spec);
 718 }
 719
 720 static noinline_for_stack
 721 char *ip4_string(char *p, const u8 *addr, const char *fmt)
 722 {
 723         int i;
 724         bool leading_zeros = (fmt[0] == 'i');
 725         int index;
 726         int step;
 727
 728         switch (fmt[2]) {
 729         case 'h':
 730 #ifdef __BIG_ENDIAN
 731                 index = 0;
 732                 step = 1;
 733 #else
 734                 index = 3;
 735                 step = -1;
 736 #endif
 737                 break;
 738         case 'l':
 739                 index = 3;
 740                 step = -1;
 741                 break;
 742         case 'n':
 743         case 'b':
 744         default:
 745                 index = 0;
 746                 step = 1;
 747                 break;
 748         }
 749         for (i = 0; i < 4; i++) {
 750                 char temp[3];   /* hold each IP quad in reverse order */
 751                 int digits = put_dec_trunc(temp, addr[index]) - temp;
 752                 if (leading_zeros) {
 753                         if (digits < 3)
 754                                 *p++ = '0';
 755                         if (digits < 2)
 756                                 *p++ = '0';
 757                 }
 758                 /* reverse the digits in the quad */
 759                 while (digits--)
 760                         *p++ = temp[digits];
 761                 if (i < 3)
 762                         *p++ = '.';
 763                 index += step;
 764         }
 765         *p = '\0';
 766
 767         return p;
 768 }
 769
 770 static noinline_for_stack
 771 char *ip6_compressed_string(char *p, const char *addr)
 772 {
 773         int i, j, range;
 774         unsigned char zerolength[8];
 775         int longest = 1;
 776         int colonpos = -1;
 777         u16 word;
 778         u8 hi, lo;
 779         bool needcolon = false;
 780         bool useIPv4;
 781         struct in6_addr in6;
 782
 783         memcpy(&in6, addr, sizeof(struct in6_addr));
 784
 785         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
 786
 787         memset(zerolength, 0, sizeof(zerolength));
 788
 789         if (useIPv4)
 790                 range = 6;
 791         else
 792                 range = 8;
 793
 794         /* find position of longest 0 run */
 795         for (i = 0; i < range; i++) {
 796                 for (j = i; j < range; j++) {
 797                         if (in6.s6_addr16[j] != 0)
 798                                 break;
 799                         zerolength[i]++;
 800                 }
 801         }
 802         for (i = 0; i < range; i++) {
 803                 if (zerolength[i] > longest) {
 804                         longest = zerolength[i];
 805                         colonpos = i;
 806                 }
 807         }
 808
 809         /* emit address */
 810         for (i = 0; i < range; i++) {
 811                 if (i == colonpos) {
 812                         if (needcolon || i == 0)
 813                                 *p++ = ':';
 814                         *p++ = ':';
 815                         needcolon = false;
 816                         i += longest - 1;
 817                         continue;
 818                 }
 819                 if (needcolon) {
 820                         *p++ = ':';
 821                         needcolon = false;
 822                 }
 823                 /* hex u16 without leading 0s */
 824                 word = ntohs(in6.s6_addr16[i]);
 825                 hi = word >> 8;
 826                 lo = word & 0xff;
 827                 if (hi) {
 828                         if (hi > 0x0f)
 829                                 p = pack_hex_byte(p, hi);
 830                         else
 831                                 *p++ = hex_asc_lo(hi);
 832                         p = pack_hex_byte(p, lo);
 833                 }
 834                 else if (lo > 0x0f)
 835                         p = pack_hex_byte(p, lo);
 836                 else
 837                         *p++ = hex_asc_lo(lo);
 838                 needcolon = true;
 839         }
 840
 841         if (useIPv4) {
 842                 if (needcolon)
 843                         *p++ = ':';
 844                 p = ip4_string(p, &in6.s6_addr[12], "I4");
 845         }
 846         *p = '\0';
 847
 848         return p;
 849 }
 850
 851 static noinline_for_stack
 852 char *ip6_string(char *p, const char *addr, const char *fmt)
 853 {
 854         int i;
 855
 856         for (i = 0; i < 8; i++) {
 857                 p = pack_hex_byte(p, *addr++);
 858                 p = pack_hex_byte(p, *addr++);
 859                 if (fmt[0] == 'I' && i != 7)
 860                         *p++ = ':';
 861         }
 862         *p = '\0';
 863
 864         return p;
 865 }
 866
 867 static noinline_for_stack
 868 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
 869                       struct printf_spec spec, const char *fmt)
 870 {
 871         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
 872
 873         if (fmt[0] == 'I' && fmt[2] == 'c')
 874                 ip6_compressed_string(ip6_addr, addr);
 875         else
 876                 ip6_string(ip6_addr, addr, fmt);
 877
 878         return string(buf, end, ip6_addr, spec);
 879 }
 880
 881 static noinline_for_stack
 882 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
 883                       struct printf_spec spec, const char *fmt)
 884 {
 885         char ip4_addr[sizeof("255.255.255.255")];
 886
 887         ip4_string(ip4_addr, addr, fmt);
 888
 889         return string(buf, end, ip4_addr, spec);
 890 }
 891
 892 static noinline_for_stack
 893 char *uuid_string(char *buf, char *end, const u8 *addr,
 894                   struct printf_spec spec, const char *fmt)
 895 {
 896         char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
 897         char *p = uuid;
 898         int i;
 899         static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
 900         static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
 901         const u8 *index = be;
 902         bool uc = false;
 903
 904         switch (*(++fmt)) {
 905         case 'L':
 906                 uc = true;              /* fall-through */
 907         case 'l':
 908                 index = le;
 909                 break;
 910         case 'B':
 911                 uc = true;
 912                 break;
 913         }
 914
 915         for (i = 0; i < 16; i++) {
 916                 p = pack_hex_byte(p, addr[index[i]]);
 917                 switch (i) {
 918                 case 3:
 919                 case 5:
 920                 case 7:
 921                 case 9:
 922                         *p++ = '-';
 923                         break;
 924                 }
 925         }
 926
 927         *p = 0;
 928
 929         if (uc) {
 930                 p = uuid;
 931                 do {
 932                         *p = toupper(*p);
 933                 } while (*(++p));
 934         }
 935
 936         return string(buf, end, uuid, spec);
 937 }
 938
 939 /*
 940  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 941  * by an extra set of alphanumeric characters that are extended format
 942  * specifiers.
 943  *
 944  * Right now we handle:
 945  *
 946  * - 'F' For symbolic function descriptor pointers with offset
 947  * - 'f' For simple symbolic function names without offset
 948  * - 'S' For symbolic direct pointers with offset
 949  * - 's' For symbolic direct pointers without offset
 950  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
 951  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
 952  * - 'M' For a 6-byte MAC address, it prints the address in the
 953  *       usual colon-separated hex notation
 954  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
 955  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
 956  *       with a dash-separated hex notation
 957  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
 958  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
 959  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
 960  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
 961  *       IPv6 omits the colons (01020304...0f)
 962  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
 963  * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
 964  * - 'I6c' for IPv6 addresses printed as specified by
 965  *       http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
 966  * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
 967  *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
 968  *       Options for %pU are:
 969  *         b big endian lower case hex (default)
 970  *         B big endian UPPER case hex
 971  *         l little endian lower case hex
 972  *         L little endian UPPER case hex
 973  *           big endian output byte order is:
 974  *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
 975  *           little endian output byte order is:
 976  *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
 977  * - 'V' For a struct va_format which contains a format string * and va_list *,
 978  *       call vsnprintf(->format, *->va_list).
 979  *       Implements a "recursive vsnprintf".
 980  *       Do not use this feature without some mechanism to verify the
 981  *       correctness of the format string and va_list arguments.
 982  *
 983  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 984  * function pointers are really function descriptors, which contain a
 985  * pointer to the real address.
 986  */
 987 static noinline_for_stack
 988 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 989               struct printf_spec spec)
 990 {
 991         if (!ptr) {
 992                 /*
 993                  * Print (null) with the same width as a pointer so it makes
 994                  * tabular output look nice.
 995                  */
 996                 if (spec.field_width == -1)
 997                         spec.field_width = 2 * sizeof(void *);
 998                 return string(buf, end, "(null)", spec);
 999         }
1000
1001         switch (*fmt) {
1002         case 'F':
1003         case 'f':
1004                 ptr = dereference_function_descriptor(ptr);
1005                 /* Fallthrough */
1006         case 'S':
1007         case 's':
1008                 return symbol_string(buf, end, ptr, spec, *fmt);
1009         case 'R':
1010         case 'r':
1011                 return resource_string(buf, end, ptr, spec, fmt);
1012         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
1013         case 'm':                       /* Contiguous: 000102030405 */
1014                                         /* [mM]F (FDDI, bit reversed) */
1015                 return mac_address_string(buf, end, ptr, spec, fmt);
1016         case 'I':                       /* Formatted IP supported
1017                                          * 4:   1.2.3.4
1018                                          * 6:   0001:0203:...:0708
1019                                          * 6c:  1::708 or 1::1.2.3.4
1020                                          */
1021         case 'i':                       /* Contiguous:
1022                                          * 4:   001.002.003.004
1023                                          * 6:   000102...0f
1024                                          */
1025                 switch (fmt[1]) {
1026                 case '6':
1027                         return ip6_addr_string(buf, end, ptr, spec, fmt);
1028                 case '4':
1029                         return ip4_addr_string(buf, end, ptr, spec, fmt);
1030                 }
1031                 break;
1032         case 'U':
1033                 return uuid_string(buf, end, ptr, spec, fmt);
1034         case 'V':
1035                 return buf + vsnprintf(buf, end - buf,
1036                                        ((struct va_format *)ptr)->fmt,
1037                                        *(((struct va_format *)ptr)->va));
1038         }
1039         spec.flags |= SMALL;
1040         if (spec.field_width == -1) {
1041                 spec.field_width = 2 * sizeof(void *);
1042                 spec.flags |= ZEROPAD;
1043         }
1044         spec.base = 16;
1045
1046         return number(buf, end, (unsigned long) ptr, spec);
1047 }
1048
1049 /*
1050  * Helper function to decode printf style format.
1051  * Each call decode a token from the format and return the
1052  * number of characters read (or likely the delta where it wants
1053  * to go on the next call).
1054  * The decoded token is returned through the parameters
1055  *
1056  * 'h', 'l', or 'L' for integer fields
1057  * 'z' support added 23/7/1999 S.H.
1058  * 'z' changed to 'Z' --davidm 1/25/99
1059  * 't' added for ptrdiff_t
1060  *
1061  * @fmt: the format string
1062  * @type of the token returned
1063  * @flags: various flags such as +, -, # tokens..
1064  * @field_width: overwritten width
1065  * @base: base of the number (octal, hex, ...)
1066  * @precision: precision of a number
1067  * @qualifier: qualifier of a number (long, size_t, ...)
1068  */
1069 static noinline_for_stack
1070 int format_decode(const char *fmt, struct printf_spec *spec)
1071 {
1072         const char *start = fmt;
1073
1074         /* we finished early by reading the field width */
1075         if (spec->type == FORMAT_TYPE_WIDTH) {
1076                 if (spec->field_width < 0) {
1077                         spec->field_width = -spec->field_width;
1078                         spec->flags |= LEFT;
1079                 }
1080                 spec->type = FORMAT_TYPE_NONE;
1081                 goto precision;
1082         }
1083
1084         /* we finished early by reading the precision */
1085         if (spec->type == FORMAT_TYPE_PRECISION) {
1086                 if (spec->precision < 0)
1087                         spec->precision = 0;
1088
1089                 spec->type = FORMAT_TYPE_NONE;
1090                 goto qualifier;
1091         }
1092
1093         /* By default */
1094         spec->type = FORMAT_TYPE_NONE;
1095
1096         for (; *fmt ; ++fmt) {
1097                 if (*fmt == '%')
1098                         break;
1099         }
1100
1101         /* Return the current non-format string */
1102         if (fmt != start || !*fmt)
1103                 return fmt - start;
1104
1105         /* Process flags */
1106         spec->flags = 0;
1107
1108         while (1) { /* this also skips first '%' */
1109                 bool found = true;
1110
1111                 ++fmt;
1112
1113                 switch (*fmt) {
1114                 case '-': spec->flags |= LEFT;    break;
1115                 case '+': spec->flags |= PLUS;    break;
1116                 case ' ': spec->flags |= SPACE;   break;
1117                 case '#': spec->flags |= SPECIAL; break;
1118                 case '0': spec->flags |= ZEROPAD; break;
1119                 default:  found = false;
1120                 }
1121
1122                 if (!found)
1123                         break;
1124         }
1125
1126         /* get field width */
1127         spec->field_width = -1;
1128
1129         if (isdigit(*fmt))
1130                 spec->field_width = skip_atoi(&fmt);
1131         else if (*fmt == '*') {
1132                 /* it's the next argument */
1133                 spec->type = FORMAT_TYPE_WIDTH;
1134                 return ++fmt - start;
1135         }
1136
1137 precision:
1138         /* get the precision */
1139         spec->precision = -1;
1140         if (*fmt == '.') {
1141                 ++fmt;
1142                 if (isdigit(*fmt)) {
1143                         spec->precision = skip_atoi(&fmt);
1144                         if (spec->precision < 0)
1145                                 spec->precision = 0;
1146                 } else if (*fmt == '*') {
1147                         /* it's the next argument */
1148                         spec->type = FORMAT_TYPE_PRECISION;
1149                         return ++fmt - start;
1150                 }
1151         }
1152
1153 qualifier:
1154         /* get the conversion qualifier */
1155         spec->qualifier = -1;
1156         if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1157             TOLOWER(*fmt) == 'z' || *fmt == 't') {
1158                 spec->qualifier = *fmt++;
1159                 if (unlikely(spec->qualifier == *fmt)) {
1160                         if (spec->qualifier == 'l') {
1161                                 spec->qualifier = 'L';
1162                                 ++fmt;
1163                         } else if (spec->qualifier == 'h') {
1164                                 spec->qualifier = 'H';
1165                                 ++fmt;
1166                         }
1167                 }
1168         }
1169
1170         /* default base */
1171         spec->base = 10;
1172         switch (*fmt) {
1173         case 'c':
1174                 spec->type = FORMAT_TYPE_CHAR;
1175                 return ++fmt - start;
1176
1177         case 's':
1178                 spec->type = FORMAT_TYPE_STR;
1179                 return ++fmt - start;
1180
1181         case 'p':
1182                 spec->type = FORMAT_TYPE_PTR;
1183                 return fmt - start;
1184                 /* skip alnum */
1185
1186         case 'n':
1187                 spec->type = FORMAT_TYPE_NRCHARS;
1188                 return ++fmt - start;
1189
1190         case '%':
1191                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1192                 return ++fmt - start;
1193
1194         /* integer number formats - set up the flags and "break" */
1195         case 'o':
1196                 spec->base = 8;
1197                 break;
1198
1199         case 'x':
1200                 spec->flags |= SMALL;
1201
1202         case 'X':
1203                 spec->base = 16;
1204                 break;
1205
1206         case 'd':
1207         case 'i':
1208                 spec->flags |= SIGN;
1209         case 'u':
1210                 break;
1211
1212         default:
1213                 spec->type = FORMAT_TYPE_INVALID;
1214                 return fmt - start;
1215         }
1216
1217         if (spec->qualifier == 'L')
1218                 spec->type = FORMAT_TYPE_LONG_LONG;
1219         else if (spec->qualifier == 'l') {
1220                 if (spec->flags & SIGN)
1221                         spec->type = FORMAT_TYPE_LONG;
1222                 else
1223                         spec->type = FORMAT_TYPE_ULONG;
1224         } else if (TOLOWER(spec->qualifier) == 'z') {
1225                 spec->type = FORMAT_TYPE_SIZE_T;
1226         } else if (spec->qualifier == 't') {
1227                 spec->type = FORMAT_TYPE_PTRDIFF;
1228         } else if (spec->qualifier == 'H') {
1229                 if (spec->flags & SIGN)
1230                         spec->type = FORMAT_TYPE_BYTE;
1231                 else
1232                         spec->type = FORMAT_TYPE_UBYTE;
1233         } else if (spec->qualifier == 'h') {
1234                 if (spec->flags & SIGN)
1235                         spec->type = FORMAT_TYPE_SHORT;
1236                 else
1237                         spec->type = FORMAT_TYPE_USHORT;
1238         } else {
1239                 if (spec->flags & SIGN)
1240                         spec->type = FORMAT_TYPE_INT;
1241                 else
1242                         spec->type = FORMAT_TYPE_UINT;
1243         }
1244
1245         return ++fmt - start;
1246 }
1247
1248 /**
1249  * vsnprintf - Format a string and place it in a buffer
1250  * @buf: The buffer to place the result into
1251  * @size: The size of the buffer, including the trailing null space
1252  * @fmt: The format string to use
1253  * @args: Arguments for the format string
1254  *
1255  * This function follows C99 vsnprintf, but has some extensions:
1256  * %pS output the name of a text symbol with offset
1257  * %ps output the name of a text symbol without offset
1258  * %pF output the name of a function pointer with its offset
1259  * %pf output the name of a function pointer without its offset
1260  * %pR output the address range in a struct resource with decoded flags
1261  * %pr output the address range in a struct resource with raw flags
1262  * %pM output a 6-byte MAC address with colons
1263  * %pm output a 6-byte MAC address without colons
1264  * %pI4 print an IPv4 address without leading zeros
1265  * %pi4 print an IPv4 address with leading zeros
1266  * %pI6 print an IPv6 address with colons
1267  * %pi6 print an IPv6 address without colons
1268  * %pI6c print an IPv6 address as specified by
1269  *   http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00
1270  * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1271  *   case.
1272  * %n is ignored
1273  *
1274  * The return value is the number of characters which would
1275  * be generated for the given input, excluding the trailing
1276  * '\0', as per ISO C99. If you want to have the exact
1277  * number of characters written into @buf as return value
1278  * (not including the trailing '\0'), use vscnprintf(). If the
1279  * return is greater than or equal to @size, the resulting
1280  * string is truncated.
1281  *
1282  * Call this function if you are already dealing with a va_list.
1283  * You probably want snprintf() instead.
1284  */
1285 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1286 {
1287         unsigned long long num;
1288         char *str, *end;
1289         struct printf_spec spec = {0};
1290
1291         /* Reject out-of-range values early.  Large positive sizes are
1292            used for unknown buffer sizes. */
1293         if (WARN_ON_ONCE((int) size < 0))
1294                 return 0;
1295
1296         str = buf;
1297         end = buf + size;
1298
1299         /* Make sure end is always >= buf */
1300         if (end < buf) {
1301                 end = ((void *)-1);
1302                 size = end - buf;
1303         }
1304
1305         while (*fmt) {
1306                 const char *old_fmt = fmt;
1307                 int read = format_decode(fmt, &spec);
1308
1309                 fmt += read;
1310
1311                 switch (spec.type) {
1312                 case FORMAT_TYPE_NONE: {
1313                         int copy = read;
1314                         if (str < end) {
1315                                 if (copy > end - str)
1316                                         copy = end - str;
1317                                 memcpy(str, old_fmt, copy);
1318                         }
1319                         str += read;
1320                         break;
1321                 }
1322
1323                 case FORMAT_TYPE_WIDTH:
1324                         spec.field_width = va_arg(args, int);
1325                         break;
1326
1327                 case FORMAT_TYPE_PRECISION:
1328                         spec.precision = va_arg(args, int);
1329                         break;
1330
1331                 case FORMAT_TYPE_CHAR: {
1332                         char c;
1333
1334                         if (!(spec.flags & LEFT)) {
1335                                 while (--spec.field_width > 0) {
1336                                         if (str < end)
1337                                                 *str = ' ';
1338                                         ++str;
1339
1340                                 }
1341                         }
1342                         c = (unsigned char) va_arg(args, int);
1343                         if (str < end)
1344                                 *str = c;
1345                         ++str;
1346                         while (--spec.field_width > 0) {
1347                                 if (str < end)
1348                                         *str = ' ';
1349                                 ++str;
1350                         }
1351                         break;
1352                 }
1353
1354                 case FORMAT_TYPE_STR:
1355                         str = string(str, end, va_arg(args, char *), spec);
1356                         break;
1357
1358                 case FORMAT_TYPE_PTR:
1359                         str = pointer(fmt+1, str, end, va_arg(args, void *),
1360                                       spec);
1361                         while (isalnum(*fmt))
1362                                 fmt++;
1363                         break;
1364
1365                 case FORMAT_TYPE_PERCENT_CHAR:
1366                         if (str < end)
1367                                 *str = '%';
1368                         ++str;
1369                         break;
1370
1371                 case FORMAT_TYPE_INVALID:
1372                         if (str < end)
1373                                 *str = '%';
1374                         ++str;
1375                         break;
1376
1377                 case FORMAT_TYPE_NRCHARS: {
1378                         u8 qualifier = spec.qualifier;
1379
1380                         if (qualifier == 'l') {
1381                                 long *ip = va_arg(args, long *);
1382                                 *ip = (str - buf);
1383                         } else if (TOLOWER(qualifier) == 'z') {
1384                                 size_t *ip = va_arg(args, size_t *);
1385                                 *ip = (str - buf);
1386                         } else {
1387                                 int *ip = va_arg(args, int *);
1388                                 *ip = (str - buf);
1389                         }
1390                         break;
1391                 }
1392
1393                 default:
1394                         switch (spec.type) {
1395                         case FORMAT_TYPE_LONG_LONG:
1396                                 num = va_arg(args, long long);
1397                                 break;
1398                         case FORMAT_TYPE_ULONG:
1399                                 num = va_arg(args, unsigned long);
1400                                 break;
1401                         case FORMAT_TYPE_LONG:
1402                                 num = va_arg(args, long);
1403                                 break;
1404                         case FORMAT_TYPE_SIZE_T:
1405                                 num = va_arg(args, size_t);
1406                                 break;
1407                         case FORMAT_TYPE_PTRDIFF:
1408                                 num = va_arg(args, ptrdiff_t);
1409                                 break;
1410                         case FORMAT_TYPE_UBYTE:
1411                                 num = (unsigned char) va_arg(args, int);
1412                                 break;
1413                         case FORMAT_TYPE_BYTE:
1414                                 num = (signed char) va_arg(args, int);
1415                                 break;
1416                         case FORMAT_TYPE_USHORT:
1417                                 num = (unsigned short) va_arg(args, int);
1418                                 break;
1419                         case FORMAT_TYPE_SHORT:
1420                                 num = (short) va_arg(args, int);
1421                                 break;
1422                         case FORMAT_TYPE_INT:
1423                                 num = (int) va_arg(args, int);
1424                                 break;
1425                         default:
1426                                 num = va_arg(args, unsigned int);
1427                         }
1428
1429                         str = number(str, end, num, spec);
1430                 }
1431         }
1432
1433         if (size > 0) {
1434                 if (str < end)
1435                         *str = '\0';
1436                 else
1437                         end[-1] = '\0';
1438         }
1439
1440         /* the trailing null byte doesn't count towards the total */
1441         return str-buf;
1442
1443 }
1444 EXPORT_SYMBOL(vsnprintf);
1445
1446 /**
1447  * vscnprintf - Format a string and place it in a buffer
1448  * @buf: The buffer to place the result into
1449  * @size: The size of the buffer, including the trailing null space
1450  * @fmt: The format string to use
1451  * @args: Arguments for the format string
1452  *
1453  * The return value is the number of characters which have been written into
1454  * the @buf not including the trailing '\0'. If @size is <= 0 the function
1455  * returns 0.
1456  *
1457  * Call this function if you are already dealing with a va_list.
1458  * You probably want scnprintf() instead.
1459  *
1460  * See the vsnprintf() documentation for format string extensions over C99.
1461  */
1462 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1463 {
1464         int i;
1465
1466         i = vsnprintf(buf, size, fmt, args);
1467
1468         return (i >= size) ? (size - 1) : i;
1469 }
1470 EXPORT_SYMBOL(vscnprintf);
1471
1472 /**
1473  * snprintf - Format a string and place it in a buffer
1474  * @buf: The buffer to place the result into
1475  * @size: The size of the buffer, including the trailing null space
1476  * @fmt: The format string to use
1477  * @...: Arguments for the format string
1478  *
1479  * The return value is the number of characters which would be
1480  * generated for the given input, excluding the trailing null,
1481  * as per ISO C99.  If the return is greater than or equal to
1482  * @size, the resulting string is truncated.
1483  *
1484  * See the vsnprintf() documentation for format string extensions over C99.
1485  */
1486 int snprintf(char *buf, size_t size, const char *fmt, ...)
1487 {
1488         va_list args;
1489         int i;
1490
1491         va_start(args, fmt);
1492         i = vsnprintf(buf, size, fmt, args);
1493         va_end(args);
1494
1495         return i;
1496 }
1497 EXPORT_SYMBOL(snprintf);
1498
1499 /**
1500  * scnprintf - Format a string and place it in a buffer
1501  * @buf: The buffer to place the result into
1502  * @size: The size of the buffer, including the trailing null space
1503  * @fmt: The format string to use
1504  * @...: Arguments for the format string
1505  *
1506  * The return value is the number of characters written into @buf not including
1507  * the trailing '\0'. If @size is == 0 the function returns 0.
1508  */
1509
1510 int scnprintf(char *buf, size_t size, const char *fmt, ...)
1511 {
1512         va_list args;
1513         int i;
1514
1515         va_start(args, fmt);
1516         i = vsnprintf(buf, size, fmt, args);
1517         va_end(args);
1518
1519         if (likely(i < size))
1520                 return i;
1521         if (size != 0)
1522                 return size - 1;
1523         return 0;
1524 }
1525 EXPORT_SYMBOL(scnprintf);
1526
1527 /**
1528  * vsprintf - Format a string and place it in a buffer
1529  * @buf: The buffer to place the result into
1530  * @fmt: The format string to use
1531  * @args: Arguments for the format string
1532  *
1533  * The function returns the number of characters written
1534  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1535  * buffer overflows.
1536  *
1537  * Call this function if you are already dealing with a va_list.
1538  * You probably want sprintf() instead.
1539  *
1540  * See the vsnprintf() documentation for format string extensions over C99.
1541  */
1542 int vsprintf(char *buf, const char *fmt, va_list args)
1543 {
1544         return vsnprintf(buf, INT_MAX, fmt, args);
1545 }
1546 EXPORT_SYMBOL(vsprintf);
1547
1548 /**
1549  * sprintf - Format a string and place it in a buffer
1550  * @buf: The buffer to place the result into
1551  * @fmt: The format string to use
1552  * @...: Arguments for the format string
1553  *
1554  * The function returns the number of characters written
1555  * into @buf. Use snprintf() or scnprintf() in order to avoid
1556  * buffer overflows.
1557  *
1558  * See the vsnprintf() documentation for format string extensions over C99.
1559  */
1560 int sprintf(char *buf, const char *fmt, ...)
1561 {
1562         va_list args;
1563         int i;
1564
1565         va_start(args, fmt);
1566         i = vsnprintf(buf, INT_MAX, fmt, args);
1567         va_end(args);
1568
1569         return i;
1570 }
1571 EXPORT_SYMBOL(sprintf);
1572
1573 #ifdef CONFIG_BINARY_PRINTF
1574 /*
1575  * bprintf service:
1576  * vbin_printf() - VA arguments to binary data
1577  * bstr_printf() - Binary data to text string
1578  */
1579
1580 /**
1581  * vbin_printf - Parse a format string and place args' binary value in a buffer
1582  * @bin_buf: The buffer to place args' binary value
1583  * @size: The size of the buffer(by words(32bits), not characters)
1584  * @fmt: The format string to use
1585  * @args: Arguments for the format string
1586  *
1587  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1588  * is skiped.
1589  *
1590  * The return value is the number of words(32bits) which would be generated for
1591  * the given input.
1592  *
1593  * NOTE:
1594  * If the return value is greater than @size, the resulting bin_buf is NOT
1595  * valid for bstr_printf().
1596  */
1597 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1598 {
1599         struct printf_spec spec = {0};
1600         char *str, *end;
1601
1602         str = (char *)bin_buf;
1603         end = (char *)(bin_buf + size);
1604
1605 #define save_arg(type)                                                  \
1606 do {                                                                    \
1607         if (sizeof(type) == 8) {                                        \
1608                 unsigned long long value;                               \
1609                 str = PTR_ALIGN(str, sizeof(u32));                      \
1610                 value = va_arg(args, unsigned long long);               \
1611                 if (str + sizeof(type) <= end) {                        \
1612                         *(u32 *)str = *(u32 *)&value;                   \
1613                         *(u32 *)(str + 4) = *((u32 *)&value + 1);       \
1614                 }                                                       \
1615         } else {                                                        \
1616                 unsigned long value;                                    \
1617                 str = PTR_ALIGN(str, sizeof(type));                     \
1618                 value = va_arg(args, int);                              \
1619                 if (str + sizeof(type) <= end)                          \
1620                         *(typeof(type) *)str = (type)value;             \
1621         }                                                               \
1622         str += sizeof(type);                                            \
1623 } while (0)
1624
1625         while (*fmt) {
1626                 int read = format_decode(fmt, &spec);
1627
1628                 fmt += read;
1629
1630                 switch (spec.type) {
1631                 case FORMAT_TYPE_NONE:
1632                 case FORMAT_TYPE_INVALID:
1633                 case FORMAT_TYPE_PERCENT_CHAR:
1634                         break;
1635
1636                 case FORMAT_TYPE_WIDTH:
1637                 case FORMAT_TYPE_PRECISION:
1638                         save_arg(int);
1639                         break;
1640
1641                 case FORMAT_TYPE_CHAR:
1642                         save_arg(char);
1643                         break;
1644
1645                 case FORMAT_TYPE_STR: {
1646                         const char *save_str = va_arg(args, char *);
1647                         size_t len;
1648
1649                         if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1650                                         || (unsigned long)save_str < PAGE_SIZE)
1651                                 save_str = "(null)";
1652                         len = strlen(save_str) + 1;
1653                         if (str + len < end)
1654                                 memcpy(str, save_str, len);
1655                         str += len;
1656                         break;
1657                 }
1658
1659                 case FORMAT_TYPE_PTR:
1660                         save_arg(void *);
1661                         /* skip all alphanumeric pointer suffixes */
1662                         while (isalnum(*fmt))
1663                                 fmt++;
1664                         break;
1665
1666                 case FORMAT_TYPE_NRCHARS: {
1667                         /* skip %n 's argument */
1668                         u8 qualifier = spec.qualifier;
1669                         void *skip_arg;
1670                         if (qualifier == 'l')
1671                                 skip_arg = va_arg(args, long *);
1672                         else if (TOLOWER(qualifier) == 'z')
1673                                 skip_arg = va_arg(args, size_t *);
1674                         else
1675                                 skip_arg = va_arg(args, int *);
1676                         break;
1677                 }
1678
1679                 default:
1680                         switch (spec.type) {
1681
1682                         case FORMAT_TYPE_LONG_LONG:
1683                                 save_arg(long long);
1684                                 break;
1685                         case FORMAT_TYPE_ULONG:
1686                         case FORMAT_TYPE_LONG:
1687                                 save_arg(unsigned long);
1688                                 break;
1689                         case FORMAT_TYPE_SIZE_T:
1690                                 save_arg(size_t);
1691                                 break;
1692                         case FORMAT_TYPE_PTRDIFF:
1693                                 save_arg(ptrdiff_t);
1694                                 break;
1695                         case FORMAT_TYPE_UBYTE:
1696                         case FORMAT_TYPE_BYTE:
1697                                 save_arg(char);
1698                                 break;
1699                         case FORMAT_TYPE_USHORT:
1700                         case FORMAT_TYPE_SHORT:
1701                                 save_arg(short);
1702                                 break;
1703                         default:
1704                                 save_arg(int);
1705                         }
1706                 }
1707         }
1708
1709         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1710 #undef save_arg
1711 }
1712 EXPORT_SYMBOL_GPL(vbin_printf);
1713
1714 /**
1715  * bstr_printf - Format a string from binary arguments and place it in a buffer
1716  * @buf: The buffer to place the result into
1717  * @size: The size of the buffer, including the trailing null space
1718  * @fmt: The format string to use
1719  * @bin_buf: Binary arguments for the format string
1720  *
1721  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1722  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1723  * a binary buffer that generated by vbin_printf.
1724  *
1725  * The format follows C99 vsnprintf, but has some extensions:
1726  *  see vsnprintf comment for details.
1727  *
1728  * The return value is the number of characters which would
1729  * be generated for the given input, excluding the trailing
1730  * '\0', as per ISO C99. If you want to have the exact
1731  * number of characters written into @buf as return value
1732  * (not including the trailing '\0'), use vscnprintf(). If the
1733  * return is greater than or equal to @size, the resulting
1734  * string is truncated.
1735  */
1736 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1737 {
1738         struct printf_spec spec = {0};
1739         char *str, *end;
1740         const char *args = (const char *)bin_buf;
1741
1742         if (WARN_ON_ONCE((int) size < 0))
1743                 return 0;
1744
1745         str = buf;
1746         end = buf + size;
1747
1748 #define get_arg(type)                                                   \
1749 ({                                                                      \
1750         typeof(type) value;                                             \
1751         if (sizeof(type) == 8) {                                        \
1752                 args = PTR_ALIGN(args, sizeof(u32));                    \
1753                 *(u32 *)&value = *(u32 *)args;                          \
1754                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
1755         } else {                                                        \
1756                 args = PTR_ALIGN(args, sizeof(type));                   \
1757                 value = *(typeof(type) *)args;                          \
1758         }                                                               \
1759         args += sizeof(type);                                           \
1760         value;                                                          \
1761 })
1762
1763         /* Make sure end is always >= buf */
1764         if (end < buf) {
1765                 end = ((void *)-1);
1766                 size = end - buf;
1767         }
1768
1769         while (*fmt) {
1770                 const char *old_fmt = fmt;
1771                 int read = format_decode(fmt, &spec);
1772
1773                 fmt += read;
1774
1775                 switch (spec.type) {
1776                 case FORMAT_TYPE_NONE: {
1777                         int copy = read;
1778                         if (str < end) {
1779                                 if (copy > end - str)
1780                                         copy = end - str;
1781                                 memcpy(str, old_fmt, copy);
1782                         }
1783                         str += read;
1784                         break;
1785                 }
1786
1787                 case FORMAT_TYPE_WIDTH:
1788                         spec.field_width = get_arg(int);
1789                         break;
1790
1791                 case FORMAT_TYPE_PRECISION:
1792                         spec.precision = get_arg(int);
1793                         break;
1794
1795                 case FORMAT_TYPE_CHAR: {
1796                         char c;
1797
1798                         if (!(spec.flags & LEFT)) {
1799                                 while (--spec.field_width > 0) {
1800                                         if (str < end)
1801                                                 *str = ' ';
1802                                         ++str;
1803                                 }
1804                         }
1805                         c = (unsigned char) get_arg(char);
1806                         if (str < end)
1807                                 *str = c;
1808                         ++str;
1809                         while (--spec.field_width > 0) {
1810                                 if (str < end)
1811                                         *str = ' ';
1812                                 ++str;
1813                         }
1814                         break;
1815                 }
1816
1817                 case FORMAT_TYPE_STR: {
1818                         const char *str_arg = args;
1819                         args += strlen(str_arg) + 1;
1820                         str = string(str, end, (char *)str_arg, spec);
1821                         break;
1822                 }
1823
1824                 case FORMAT_TYPE_PTR:
1825                         str = pointer(fmt+1, str, end, get_arg(void *), spec);
1826                         while (isalnum(*fmt))
1827                                 fmt++;
1828                         break;
1829
1830                 case FORMAT_TYPE_PERCENT_CHAR:
1831                 case FORMAT_TYPE_INVALID:
1832                         if (str < end)
1833                                 *str = '%';
1834                         ++str;
1835                         break;
1836
1837                 case FORMAT_TYPE_NRCHARS:
1838                         /* skip */
1839                         break;
1840
1841                 default: {
1842                         unsigned long long num;
1843
1844                         switch (spec.type) {
1845
1846                         case FORMAT_TYPE_LONG_LONG:
1847                                 num = get_arg(long long);
1848                                 break;
1849                         case FORMAT_TYPE_ULONG:
1850                         case FORMAT_TYPE_LONG:
1851                                 num = get_arg(unsigned long);
1852                                 break;
1853                         case FORMAT_TYPE_SIZE_T:
1854                                 num = get_arg(size_t);
1855                                 break;
1856                         case FORMAT_TYPE_PTRDIFF:
1857                                 num = get_arg(ptrdiff_t);
1858                                 break;
1859                         case FORMAT_TYPE_UBYTE:
1860                                 num = get_arg(unsigned char);
1861                                 break;
1862                         case FORMAT_TYPE_BYTE:
1863                                 num = get_arg(signed char);
1864                                 break;
1865                         case FORMAT_TYPE_USHORT:
1866                                 num = get_arg(unsigned short);
1867                                 break;
1868                         case FORMAT_TYPE_SHORT:
1869                                 num = get_arg(short);
1870                                 break;
1871                         case FORMAT_TYPE_UINT:
1872                                 num = get_arg(unsigned int);
1873                                 break;
1874                         default:
1875                                 num = get_arg(int);
1876                         }
1877
1878                         str = number(str, end, num, spec);
1879                 } /* default: */
1880                 } /* switch(spec.type) */
1881         } /* while(*fmt) */
1882
1883         if (size > 0) {
1884                 if (str < end)
1885                         *str = '\0';
1886                 else
1887                         end[-1] = '\0';
1888         }
1889
1890 #undef get_arg
1891
1892         /* the trailing null byte doesn't count towards the total */
1893         return str - buf;
1894 }
1895 EXPORT_SYMBOL_GPL(bstr_printf);
1896
1897 /**
1898  * bprintf - Parse a format string and place args' binary value in a buffer
1899  * @bin_buf: The buffer to place args' binary value
1900  * @size: The size of the buffer(by words(32bits), not characters)
1901  * @fmt: The format string to use
1902  * @...: Arguments for the format string
1903  *
1904  * The function returns the number of words(u32) written
1905  * into @bin_buf.
1906  */
1907 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1908 {
1909         va_list args;
1910         int ret;
1911
1912         va_start(args, fmt);
1913         ret = vbin_printf(bin_buf, size, fmt, args);
1914         va_end(args);
1915
1916         return ret;
1917 }
1918 EXPORT_SYMBOL_GPL(bprintf);
1919
1920 #endif /* CONFIG_BINARY_PRINTF */
1921
1922 /**
1923  * vsscanf - Unformat a buffer into a list of arguments
1924  * @buf:        input buffer
1925  * @fmt:        format of buffer
1926  * @args:       arguments
1927  */
1928 int vsscanf(const char *buf, const char *fmt, va_list args)
1929 {
1930         const char *str = buf;
1931         char *next;
1932         char digit;
1933         int num = 0;
1934         u8 qualifier;
1935         u8 base;
1936         s16 field_width;
1937         bool is_sign;
1938
1939         while (*fmt && *str) {
1940                 /* skip any white space in format */
1941                 /* white space in format matchs any amount of
1942                  * white space, including none, in the input.
1943                  */
1944                 if (isspace(*fmt)) {
1945                         fmt = skip_spaces(++fmt);
1946                         str = skip_spaces(str);
1947                 }
1948
1949                 /* anything that is not a conversion must match exactly */
1950                 if (*fmt != '%' && *fmt) {
1951                         if (*fmt++ != *str++)
1952                                 break;
1953                         continue;
1954                 }
1955
1956                 if (!*fmt)
1957                         break;
1958                 ++fmt;
1959
1960                 /* skip this conversion.
1961                  * advance both strings to next white space
1962                  */
1963                 if (*fmt == '*') {
1964                         while (!isspace(*fmt) && *fmt != '%' && *fmt)
1965                                 fmt++;
1966                         while (!isspace(*str) && *str)
1967                                 str++;
1968                         continue;
1969                 }
1970
1971                 /* get field width */
1972                 field_width = -1;
1973                 if (isdigit(*fmt))
1974                         field_width = skip_atoi(&fmt);
1975
1976                 /* get conversion qualifier */
1977                 qualifier = -1;
1978                 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
1979                     TOLOWER(*fmt) == 'z') {
1980                         qualifier = *fmt++;
1981                         if (unlikely(qualifier == *fmt)) {
1982                                 if (qualifier == 'h') {
1983                                         qualifier = 'H';
1984                                         fmt++;
1985                                 } else if (qualifier == 'l') {
1986                                         qualifier = 'L';
1987                                         fmt++;
1988                                 }
1989                         }
1990                 }
1991
1992                 if (!*fmt || !*str)
1993                         break;
1994
1995                 base = 10;
1996                 is_sign = 0;
1997
1998                 switch (*fmt++) {
1999                 case 'c':
2000                 {
2001                         char *s = (char *)va_arg(args, char*);
2002                         if (field_width == -1)
2003                                 field_width = 1;
2004                         do {
2005                                 *s++ = *str++;
2006                         } while (--field_width > 0 && *str);
2007                         num++;
2008                 }
2009                 continue;
2010                 case 's':
2011                 {
2012                         char *s = (char *)va_arg(args, char *);
2013                         if (field_width == -1)
2014                                 field_width = SHRT_MAX;
2015                         /* first, skip leading white space in buffer */
2016                         str = skip_spaces(str);
2017
2018                         /* now copy until next white space */
2019                         while (*str && !isspace(*str) && field_width--)
2020                                 *s++ = *str++;
2021                         *s = '\0';
2022                         num++;
2023                 }
2024                 continue;
2025                 case 'n':
2026                         /* return number of characters read so far */
2027                 {
2028                         int *i = (int *)va_arg(args, int*);
2029                         *i = str - buf;
2030                 }
2031                 continue;
2032                 case 'o':
2033                         base = 8;
2034                         break;
2035                 case 'x':
2036                 case 'X':
2037                         base = 16;
2038                         break;
2039                 case 'i':
2040                         base = 0;
2041                 case 'd':
2042                         is_sign = 1;
2043                 case 'u':
2044                         break;
2045                 case '%':
2046                         /* looking for '%' in str */
2047                         if (*str++ != '%')
2048                                 return num;
2049                         continue;
2050                 default:
2051                         /* invalid format; stop here */
2052                         return num;
2053                 }
2054
2055                 /* have some sort of integer conversion.
2056                  * first, skip white space in buffer.
2057                  */
2058                 str = skip_spaces(str);
2059
2060                 digit = *str;
2061                 if (is_sign && digit == '-')
2062                         digit = *(str + 1);
2063
2064                 if (!digit
2065                     || (base == 16 && !isxdigit(digit))
2066                     || (base == 10 && !isdigit(digit))
2067                     || (base == 8 && (!isdigit(digit) || digit > '7'))
2068                     || (base == 0 && !isdigit(digit)))
2069                         break;
2070
2071                 switch (qualifier) {
2072                 case 'H':       /* that's 'hh' in format */
2073                         if (is_sign) {
2074                                 signed char *s = (signed char *)va_arg(args, signed char *);
2075                                 *s = (signed char)simple_strtol(str, &next, base);
2076                         } else {
2077                                 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
2078                                 *s = (unsigned char)simple_strtoul(str, &next, base);
2079                         }
2080                         break;
2081                 case 'h':
2082                         if (is_sign) {
2083                                 short *s = (short *)va_arg(args, short *);
2084                                 *s = (short)simple_strtol(str, &next, base);
2085                         } else {
2086                                 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
2087                                 *s = (unsigned short)simple_strtoul(str, &next, base);
2088                         }
2089                         break;
2090                 case 'l':
2091                         if (is_sign) {
2092                                 long *l = (long *)va_arg(args, long *);
2093                                 *l = simple_strtol(str, &next, base);
2094                         } else {
2095                                 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
2096                                 *l = simple_strtoul(str, &next, base);
2097                         }
2098                         break;
2099                 case 'L':
2100                         if (is_sign) {
2101                                 long long *l = (long long *)va_arg(args, long long *);
2102                                 *l = simple_strtoll(str, &next, base);
2103                         } else {
2104                                 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
2105                                 *l = simple_strtoull(str, &next, base);
2106                         }
2107                         break;
2108                 case 'Z':
2109                 case 'z':
2110                 {
2111                         size_t *s = (size_t *)va_arg(args, size_t *);
2112                         *s = (size_t)simple_strtoul(str, &next, base);
2113                 }
2114                 break;
2115                 default:
2116                         if (is_sign) {
2117                                 int *i = (int *)va_arg(args, int *);
2118                                 *i = (int)simple_strtol(str, &next, base);
2119                         } else {
2120                                 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2121                                 *i = (unsigned int)simple_strtoul(str, &next, base);
2122                         }
2123                         break;
2124                 }
2125                 num++;
2126
2127                 if (!next)
2128                         break;
2129                 str = next;
2130         }
2131
2132         /*
2133          * Now we've come all the way through so either the input string or the
2134          * format ended. In the former case, there can be a %n at the current
2135          * position in the format that needs to be filled.
2136          */
2137         if (*fmt == '%' && *(fmt + 1) == 'n') {
2138                 int *p = (int *)va_arg(args, int *);
2139                 *p = str - buf;
2140         }
2141
2142         return num;
2143 }
2144 EXPORT_SYMBOL(vsscanf);
2145
2146 /**
2147  * sscanf - Unformat a buffer into a list of arguments
2148  * @buf:        input buffer
2149  * @fmt:        formatting of buffer
2150  * @...:        resulting arguments
2151  */
2152 int sscanf(const char *buf, const char *fmt, ...)
2153 {
2154         va_list args;
2155         int i;
2156
2157         va_start(args, fmt);
2158         i = vsscanf(buf, fmt, args);
2159         va_end(args);
2160
2161         return i;
2162 }
2163 EXPORT_SYMBOL(sscanf);