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_strtoul - convert a string to an unsigned 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 simple_strtoul(const char *cp, char **endp, unsigned int base)
  56 {
  57         unsigned 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
  75         if (endp)
  76                 *endp = (char *)cp;
  77         return result;
  78 }
  79 EXPORT_SYMBOL(simple_strtoul);
  80
  81 /**
  82  * simple_strtol - convert a string to a signed 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 long simple_strtol(const char *cp, char **endp, unsigned int base)
  88 {
  89         if(*cp == '-')
  90                 return -simple_strtoul(cp + 1, endp, base);
  91         return simple_strtoul(cp, endp, base);
  92 }
  93 EXPORT_SYMBOL(simple_strtol);
  94
  95 /**
  96  * simple_strtoull - convert a string to an unsigned long long
  97  * @cp: The start of the string
  98  * @endp: A pointer to the end of the parsed string will be placed here
  99  * @base: The number base to use
 100  */
 101 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
 102 {
 103         unsigned long long result = 0;
 104
 105         if (!base)
 106                 base = simple_guess_base(cp);
 107
 108         if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
 109                 cp += 2;
 110
 111         while (isxdigit(*cp)) {
 112                 unsigned int value;
 113
 114                 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
 115                 if (value >= base)
 116                         break;
 117                 result = result * base + value;
 118                 cp++;
 119         }
 120
 121         if (endp)
 122                 *endp = (char *)cp;
 123         return result;
 124 }
 125 EXPORT_SYMBOL(simple_strtoull);
 126
 127 /**
 128  * simple_strtoll - convert a string to a signed long long
 129  * @cp: The start of the string
 130  * @endp: A pointer to the end of the parsed string will be placed here
 131  * @base: The number base to use
 132  */
 133 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 134 {
 135         if(*cp=='-')
 136                 return -simple_strtoull(cp + 1, endp, base);
 137         return simple_strtoull(cp, endp, base);
 138 }
 139
 140 /**
 141  * strict_strtoul - convert a string to an unsigned long strictly
 142  * @cp: The string to be converted
 143  * @base: The number base to use
 144  * @res: The converted result value
 145  *
 146  * strict_strtoul converts a string to an unsigned long only if the
 147  * string is really an unsigned long string, any string containing
 148  * any invalid char at the tail will be rejected and -EINVAL is returned,
 149  * only a newline char at the tail is acceptible because people generally
 150  * change a module parameter in the following way:
 151  *
 152  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 153  *
 154  * echo will append a newline to the tail.
 155  *
 156  * It returns 0 if conversion is successful and *res is set to the converted
 157  * value, otherwise it returns -EINVAL and *res is set to 0.
 158  *
 159  * simple_strtoul just ignores the successive invalid characters and
 160  * return the converted value of prefix part of the string.
 161  */
 162 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
 163 {
 164         char *tail;
 165         unsigned long val;
 166         size_t len;
 167
 168         *res = 0;
 169         len = strlen(cp);
 170         if (len == 0)
 171                 return -EINVAL;
 172
 173         val = simple_strtoul(cp, &tail, base);
 174         if (tail == cp)
 175                 return -EINVAL;
 176         if ((*tail == '\0') ||
 177                 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 178                 *res = val;
 179                 return 0;
 180         }
 181
 182         return -EINVAL;
 183 }
 184 EXPORT_SYMBOL(strict_strtoul);
 185
 186 /**
 187  * strict_strtol - convert a string to a long strictly
 188  * @cp: The string to be converted
 189  * @base: The number base to use
 190  * @res: The converted result value
 191  *
 192  * strict_strtol is similiar to strict_strtoul, but it allows the first
 193  * character of a string is '-'.
 194  *
 195  * It returns 0 if conversion is successful and *res is set to the converted
 196  * value, otherwise it returns -EINVAL and *res is set to 0.
 197  */
 198 int strict_strtol(const char *cp, unsigned int base, long *res)
 199 {
 200         int ret;
 201         if (*cp == '-') {
 202                 ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
 203                 if (!ret)
 204                         *res = -(*res);
 205         } else {
 206                 ret = strict_strtoul(cp, base, (unsigned long *)res);
 207         }
 208
 209         return ret;
 210 }
 211 EXPORT_SYMBOL(strict_strtol);
 212
 213 /**
 214  * strict_strtoull - convert a string to an unsigned long long strictly
 215  * @cp: The string to be converted
 216  * @base: The number base to use
 217  * @res: The converted result value
 218  *
 219  * strict_strtoull converts a string to an unsigned long long only if the
 220  * string is really an unsigned long long string, any string containing
 221  * any invalid char at the tail will be rejected and -EINVAL is returned,
 222  * only a newline char at the tail is acceptible because people generally
 223  * change a module parameter in the following way:
 224  *
 225  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 226  *
 227  * echo will append a newline to the tail of the string.
 228  *
 229  * It returns 0 if conversion is successful and *res is set to the converted
 230  * value, otherwise it returns -EINVAL and *res is set to 0.
 231  *
 232  * simple_strtoull just ignores the successive invalid characters and
 233  * return the converted value of prefix part of the string.
 234  */
 235 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
 236 {
 237         char *tail;
 238         unsigned long long val;
 239         size_t len;
 240
 241         *res = 0;
 242         len = strlen(cp);
 243         if (len == 0)
 244                 return -EINVAL;
 245
 246         val = simple_strtoull(cp, &tail, base);
 247         if (tail == cp)
 248                 return -EINVAL;
 249         if ((*tail == '\0') ||
 250                 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 251                 *res = val;
 252                 return 0;
 253         }
 254
 255         return -EINVAL;
 256 }
 257 EXPORT_SYMBOL(strict_strtoull);
 258
 259 /**
 260  * strict_strtoll - convert a string to a long long strictly
 261  * @cp: The string to be converted
 262  * @base: The number base to use
 263  * @res: The converted result value
 264  *
 265  * strict_strtoll is similiar to strict_strtoull, but it allows the first
 266  * character of a string is '-'.
 267  *
 268  * It returns 0 if conversion is successful and *res is set to the converted
 269  * value, otherwise it returns -EINVAL and *res is set to 0.
 270  */
 271 int strict_strtoll(const char *cp, unsigned int base, long long *res)
 272 {
 273         int ret;
 274         if (*cp == '-') {
 275                 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
 276                 if (!ret)
 277                         *res = -(*res);
 278         } else {
 279                 ret = strict_strtoull(cp, base, (unsigned long long *)res);
 280         }
 281
 282         return ret;
 283 }
 284 EXPORT_SYMBOL(strict_strtoll);
 285
 286 static int skip_atoi(const char **s)
 287 {
 288         int i=0;
 289
 290         while (isdigit(**s))
 291                 i = i*10 + *((*s)++) - '0';
 292         return i;
 293 }
 294
 295 /* Decimal conversion is by far the most typical, and is used
 296  * for /proc and /sys data. This directly impacts e.g. top performance
 297  * with many processes running. We optimize it for speed
 298  * using code from
 299  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 300  * (with permission from the author, Douglas W. Jones). */
 301
 302 /* Formats correctly any integer in [0,99999].
 303  * Outputs from one to five digits depending on input.
 304  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
 305 static char* put_dec_trunc(char *buf, unsigned q)
 306 {
 307         unsigned d3, d2, d1, d0;
 308         d1 = (q>>4) & 0xf;
 309         d2 = (q>>8) & 0xf;
 310         d3 = (q>>12);
 311
 312         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 313         q = (d0 * 0xcd) >> 11;
 314         d0 = d0 - 10*q;
 315         *buf++ = d0 + '0'; /* least significant digit */
 316         d1 = q + 9*d3 + 5*d2 + d1;
 317         if (d1 != 0) {
 318                 q = (d1 * 0xcd) >> 11;
 319                 d1 = d1 - 10*q;
 320                 *buf++ = d1 + '0'; /* next digit */
 321
 322                 d2 = q + 2*d2;
 323                 if ((d2 != 0) || (d3 != 0)) {
 324                         q = (d2 * 0xd) >> 7;
 325                         d2 = d2 - 10*q;
 326                         *buf++ = d2 + '0'; /* next digit */
 327
 328                         d3 = q + 4*d3;
 329                         if (d3 != 0) {
 330                                 q = (d3 * 0xcd) >> 11;
 331                                 d3 = d3 - 10*q;
 332                                 *buf++ = d3 + '0';  /* next digit */
 333                                 if (q != 0)
 334                                         *buf++ = q + '0';  /* most sign. digit */
 335                         }
 336                 }
 337         }
 338         return buf;
 339 }
 340 /* Same with if's removed. Always emits five digits */
 341 static char* put_dec_full(char *buf, unsigned q)
 342 {
 343         /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
 344         /* but anyway, gcc produces better code with full-sized ints */
 345         unsigned d3, d2, d1, d0;
 346         d1 = (q>>4) & 0xf;
 347         d2 = (q>>8) & 0xf;
 348         d3 = (q>>12);
 349
 350         /* Possible ways to approx. divide by 10 */
 351         /* gcc -O2 replaces multiply with shifts and adds */
 352         // (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
 353         // (x * 0x67) >> 10:  1100111
 354         // (x * 0x34) >> 9:    110100 - same
 355         // (x * 0x1a) >> 8:     11010 - same
 356         // (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
 357
 358         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 359         q = (d0 * 0xcd) >> 11;
 360         d0 = d0 - 10*q;
 361         *buf++ = d0 + '0';
 362         d1 = q + 9*d3 + 5*d2 + d1;
 363                 q = (d1 * 0xcd) >> 11;
 364                 d1 = d1 - 10*q;
 365                 *buf++ = d1 + '0';
 366
 367                 d2 = q + 2*d2;
 368                         q = (d2 * 0xd) >> 7;
 369                         d2 = d2 - 10*q;
 370                         *buf++ = d2 + '0';
 371
 372                         d3 = q + 4*d3;
 373                                 q = (d3 * 0xcd) >> 11; /* - shorter code */
 374                                 /* q = (d3 * 0x67) >> 10; - would also work */
 375                                 d3 = d3 - 10*q;
 376                                 *buf++ = d3 + '0';
 377                                         *buf++ = q + '0';
 378         return buf;
 379 }
 380 /* No inlining helps gcc to use registers better */
 381 static noinline char* put_dec(char *buf, unsigned long long num)
 382 {
 383         while (1) {
 384                 unsigned rem;
 385                 if (num < 100000)
 386                         return put_dec_trunc(buf, num);
 387                 rem = do_div(num, 100000);
 388                 buf = put_dec_full(buf, rem);
 389         }
 390 }
 391
 392 #define ZEROPAD 1               /* pad with zero */
 393 #define SIGN    2               /* unsigned/signed long */
 394 #define PLUS    4               /* show plus */
 395 #define SPACE   8               /* space if plus */
 396 #define LEFT    16              /* left justified */
 397 #define SMALL   32              /* Must be 32 == 0x20 */
 398 #define SPECIAL 64              /* 0x */
 399
 400 enum format_type {
 401         FORMAT_TYPE_NONE, /* Just a string part */
 402         FORMAT_TYPE_WIDTH,
 403         FORMAT_TYPE_PRECISION,
 404         FORMAT_TYPE_CHAR,
 405         FORMAT_TYPE_STR,
 406         FORMAT_TYPE_PTR,
 407         FORMAT_TYPE_PERCENT_CHAR,
 408         FORMAT_TYPE_INVALID,
 409         FORMAT_TYPE_LONG_LONG,
 410         FORMAT_TYPE_ULONG,
 411         FORMAT_TYPE_LONG,
 412         FORMAT_TYPE_UBYTE,
 413         FORMAT_TYPE_BYTE,
 414         FORMAT_TYPE_USHORT,
 415         FORMAT_TYPE_SHORT,
 416         FORMAT_TYPE_UINT,
 417         FORMAT_TYPE_INT,
 418         FORMAT_TYPE_NRCHARS,
 419         FORMAT_TYPE_SIZE_T,
 420         FORMAT_TYPE_PTRDIFF
 421 };
 422
 423 struct printf_spec {
 424         enum format_type        type;
 425         int                     flags;          /* flags to number() */
 426         int                     field_width;    /* width of output field */
 427         int                     base;
 428         int                     precision;      /* # of digits/chars */
 429         int                     qualifier;
 430 };
 431
 432 static char *number(char *buf, char *end, unsigned long long num,
 433                         struct printf_spec spec)
 434 {
 435         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 436         static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 437
 438         char tmp[66];
 439         char sign;
 440         char locase;
 441         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 442         int i;
 443
 444         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 445          * produces same digits or (maybe lowercased) letters */
 446         locase = (spec.flags & SMALL);
 447         if (spec.flags & LEFT)
 448                 spec.flags &= ~ZEROPAD;
 449         sign = 0;
 450         if (spec.flags & SIGN) {
 451                 if ((signed long long) num < 0) {
 452                         sign = '-';
 453                         num = - (signed long long) num;
 454                         spec.field_width--;
 455                 } else if (spec.flags & PLUS) {
 456                         sign = '+';
 457                         spec.field_width--;
 458                 } else if (spec.flags & SPACE) {
 459                         sign = ' ';
 460                         spec.field_width--;
 461                 }
 462         }
 463         if (need_pfx) {
 464                 spec.field_width--;
 465                 if (spec.base == 16)
 466                         spec.field_width--;
 467         }
 468
 469         /* generate full string in tmp[], in reverse order */
 470         i = 0;
 471         if (num == 0)
 472                 tmp[i++] = '0';
 473         /* Generic code, for any base:
 474         else do {
 475                 tmp[i++] = (digits[do_div(num,base)] | locase);
 476         } while (num != 0);
 477         */
 478         else if (spec.base != 10) { /* 8 or 16 */
 479                 int mask = spec.base - 1;
 480                 int shift = 3;
 481                 if (spec.base == 16) shift = 4;
 482                 do {
 483                         tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 484                         num >>= shift;
 485                 } while (num);
 486         } else { /* base 10 */
 487                 i = put_dec(tmp, num) - tmp;
 488         }
 489
 490         /* printing 100 using %2d gives "100", not "00" */
 491         if (i > spec.precision)
 492                 spec.precision = i;
 493         /* leading space padding */
 494         spec.field_width -= spec.precision;
 495         if (!(spec.flags & (ZEROPAD+LEFT))) {
 496                 while(--spec.field_width >= 0) {
 497                         if (buf < end)
 498                                 *buf = ' ';
 499                         ++buf;
 500                 }
 501         }
 502         /* sign */
 503         if (sign) {
 504                 if (buf < end)
 505                         *buf = sign;
 506                 ++buf;
 507         }
 508         /* "0x" / "0" prefix */
 509         if (need_pfx) {
 510                 if (buf < end)
 511                         *buf = '0';
 512                 ++buf;
 513                 if (spec.base == 16) {
 514                         if (buf < end)
 515                                 *buf = ('X' | locase);
 516                         ++buf;
 517                 }
 518         }
 519         /* zero or space padding */
 520         if (!(spec.flags & LEFT)) {
 521                 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
 522                 while (--spec.field_width >= 0) {
 523                         if (buf < end)
 524                                 *buf = c;
 525                         ++buf;
 526                 }
 527         }
 528         /* hmm even more zero padding? */
 529         while (i <= --spec.precision) {
 530                 if (buf < end)
 531                         *buf = '0';
 532                 ++buf;
 533         }
 534         /* actual digits of result */
 535         while (--i >= 0) {
 536                 if (buf < end)
 537                         *buf = tmp[i];
 538                 ++buf;
 539         }
 540         /* trailing space padding */
 541         while (--spec.field_width >= 0) {
 542                 if (buf < end)
 543                         *buf = ' ';
 544                 ++buf;
 545         }
 546         return buf;
 547 }
 548
 549 static char *string(char *buf, char *end, const char *s, struct printf_spec spec)
 550 {
 551         int len, i;
 552
 553         if ((unsigned long)s < PAGE_SIZE)
 554                 s = "(null)";
 555
 556         len = strnlen(s, spec.precision);
 557
 558         if (!(spec.flags & LEFT)) {
 559                 while (len < spec.field_width--) {
 560                         if (buf < end)
 561                                 *buf = ' ';
 562                         ++buf;
 563                 }
 564         }
 565         for (i = 0; i < len; ++i) {
 566                 if (buf < end)
 567                         *buf = *s;
 568                 ++buf; ++s;
 569         }
 570         while (len < spec.field_width--) {
 571                 if (buf < end)
 572                         *buf = ' ';
 573                 ++buf;
 574         }
 575         return buf;
 576 }
 577
 578 static char *symbol_string(char *buf, char *end, void *ptr,
 579                                 struct printf_spec spec, char ext)
 580 {
 581         unsigned long value = (unsigned long) ptr;
 582 #ifdef CONFIG_KALLSYMS
 583         char sym[KSYM_SYMBOL_LEN];
 584         if (ext != 'f' && ext != 's')
 585                 sprint_symbol(sym, value);
 586         else
 587                 kallsyms_lookup(value, NULL, NULL, NULL, sym);
 588         return string(buf, end, sym, spec);
 589 #else
 590         spec.field_width = 2*sizeof(void *);
 591         spec.flags |= SPECIAL | SMALL | ZEROPAD;
 592         spec.base = 16;
 593         return number(buf, end, value, spec);
 594 #endif
 595 }
 596
 597 static char *resource_string(char *buf, char *end, struct resource *res,
 598                                 struct printf_spec spec, const char *fmt)
 599 {
 600 #ifndef IO_RSRC_PRINTK_SIZE
 601 #define IO_RSRC_PRINTK_SIZE     6
 602 #endif
 603
 604 #ifndef MEM_RSRC_PRINTK_SIZE
 605 #define MEM_RSRC_PRINTK_SIZE    10
 606 #endif
 607         struct printf_spec hex_spec = {
 608                 .base = 16,
 609                 .precision = -1,
 610                 .flags = SPECIAL | SMALL | ZEROPAD,
 611         };
 612         struct printf_spec dec_spec = {
 613                 .base = 10,
 614                 .precision = -1,
 615                 .flags = 0,
 616         };
 617         struct printf_spec str_spec = {
 618                 .field_width = -1,
 619                 .precision = 10,
 620                 .flags = LEFT,
 621         };
 622         struct printf_spec flag_spec = {
 623                 .base = 16,
 624                 .precision = -1,
 625                 .flags = SPECIAL | SMALL,
 626         };
 627
 628         /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 629          * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 630 #define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
 631 #define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
 632 #define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref disabled]")
 633 #define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
 634         char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 635                      2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 636
 637         char *p = sym, *pend = sym + sizeof(sym);
 638         int size = -1, addr = 0;
 639         int decode = (fmt[0] == 'R') ? 1 : 0;
 640
 641         if (res->flags & IORESOURCE_IO) {
 642                 size = IO_RSRC_PRINTK_SIZE;
 643                 addr = 1;
 644         } else if (res->flags & IORESOURCE_MEM) {
 645                 size = MEM_RSRC_PRINTK_SIZE;
 646                 addr = 1;
 647         }
 648
 649         *p++ = '[';
 650         if (res->flags & IORESOURCE_IO)
 651                 p = string(p, pend, "io  ", str_spec);
 652         else if (res->flags & IORESOURCE_MEM)
 653                 p = string(p, pend, "mem ", str_spec);
 654         else if (res->flags & IORESOURCE_IRQ)
 655                 p = string(p, pend, "irq ", str_spec);
 656         else if (res->flags & IORESOURCE_DMA)
 657                 p = string(p, pend, "dma ", str_spec);
 658         else {
 659                 p = string(p, pend, "??? ", str_spec);
 660                 decode = 0;
 661         }
 662         hex_spec.field_width = size;
 663         p = number(p, pend, res->start, addr ? hex_spec : dec_spec);
 664         if (res->start != res->end) {
 665                 *p++ = '-';
 666                 p = number(p, pend, res->end, addr ? hex_spec : dec_spec);
 667         }
 668         if (decode) {
 669                 if (res->flags & IORESOURCE_MEM_64)
 670                         p = string(p, pend, " 64bit", str_spec);
 671                 if (res->flags & IORESOURCE_PREFETCH)
 672                         p = string(p, pend, " pref", str_spec);
 673                 if (res->flags & IORESOURCE_DISABLED)
 674                         p = string(p, pend, " disabled", str_spec);
 675         } else {
 676                 p = string(p, pend, " flags ", str_spec);
 677                 p = number(p, pend, res->flags, flag_spec);
 678         }
 679         *p++ = ']';
 680         *p = '\0';
 681
 682         return string(buf, end, sym, spec);
 683 }
 684
 685 static char *mac_address_string(char *buf, char *end, u8 *addr,
 686                                 struct printf_spec spec, const char *fmt)
 687 {
 688         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
 689         char *p = mac_addr;
 690         int i;
 691
 692         for (i = 0; i < 6; i++) {
 693                 p = pack_hex_byte(p, addr[i]);
 694                 if (fmt[0] == 'M' && i != 5)
 695                         *p++ = ':';
 696         }
 697         *p = '\0';
 698
 699         return string(buf, end, mac_addr, spec);
 700 }
 701
 702 static char *ip4_string(char *p, const u8 *addr, bool leading_zeros)
 703 {
 704         int i;
 705
 706         for (i = 0; i < 4; i++) {
 707                 char temp[3];   /* hold each IP quad in reverse order */
 708                 int digits = put_dec_trunc(temp, addr[i]) - temp;
 709                 if (leading_zeros) {
 710                         if (digits < 3)
 711                                 *p++ = '0';
 712                         if (digits < 2)
 713                                 *p++ = '0';
 714                 }
 715                 /* reverse the digits in the quad */
 716                 while (digits--)
 717                         *p++ = temp[digits];
 718                 if (i < 3)
 719                         *p++ = '.';
 720         }
 721
 722         *p = '\0';
 723         return p;
 724 }
 725
 726 static char *ip6_compressed_string(char *p, const char *addr)
 727 {
 728         int i;
 729         int j;
 730         int range;
 731         unsigned char zerolength[8];
 732         int longest = 1;
 733         int colonpos = -1;
 734         u16 word;
 735         u8 hi;
 736         u8 lo;
 737         bool needcolon = false;
 738         bool useIPv4;
 739         struct in6_addr in6;
 740
 741         memcpy(&in6, addr, sizeof(struct in6_addr));
 742
 743         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
 744
 745         memset(zerolength, 0, sizeof(zerolength));
 746
 747         if (useIPv4)
 748                 range = 6;
 749         else
 750                 range = 8;
 751
 752         /* find position of longest 0 run */
 753         for (i = 0; i < range; i++) {
 754                 for (j = i; j < range; j++) {
 755                         if (in6.s6_addr16[j] != 0)
 756                                 break;
 757                         zerolength[i]++;
 758                 }
 759         }
 760         for (i = 0; i < range; i++) {
 761                 if (zerolength[i] > longest) {
 762                         longest = zerolength[i];
 763                         colonpos = i;
 764                 }
 765         }
 766
 767         /* emit address */
 768         for (i = 0; i < range; i++) {
 769                 if (i == colonpos) {
 770                         if (needcolon || i == 0)
 771                                 *p++ = ':';
 772                         *p++ = ':';
 773                         needcolon = false;
 774                         i += longest - 1;
 775                         continue;
 776                 }
 777                 if (needcolon) {
 778                         *p++ = ':';
 779                         needcolon = false;
 780                 }
 781                 /* hex u16 without leading 0s */
 782                 word = ntohs(in6.s6_addr16[i]);
 783                 hi = word >> 8;
 784                 lo = word & 0xff;
 785                 if (hi) {
 786                         if (hi > 0x0f)
 787                                 p = pack_hex_byte(p, hi);
 788                         else
 789                                 *p++ = hex_asc_lo(hi);
 790                 }
 791                 if (hi || lo > 0x0f)
 792                         p = pack_hex_byte(p, lo);
 793                 else
 794                         *p++ = hex_asc_lo(lo);
 795                 needcolon = true;
 796         }
 797
 798         if (useIPv4) {
 799                 if (needcolon)
 800                         *p++ = ':';
 801                 p = ip4_string(p, &in6.s6_addr[12], false);
 802         }
 803
 804         *p = '\0';
 805         return p;
 806 }
 807
 808 static char *ip6_string(char *p, const char *addr, const char *fmt)
 809 {
 810         int i;
 811         for (i = 0; i < 8; i++) {
 812                 p = pack_hex_byte(p, *addr++);
 813                 p = pack_hex_byte(p, *addr++);
 814                 if (fmt[0] == 'I' && i != 7)
 815                         *p++ = ':';
 816         }
 817
 818         *p = '\0';
 819         return p;
 820 }
 821
 822 static char *ip6_addr_string(char *buf, char *end, const u8 *addr,
 823                              struct printf_spec spec, const char *fmt)
 824 {
 825         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
 826
 827         if (fmt[0] == 'I' && fmt[2] == 'c')
 828                 ip6_compressed_string(ip6_addr, addr);
 829         else
 830                 ip6_string(ip6_addr, addr, fmt);
 831
 832         return string(buf, end, ip6_addr, spec);
 833 }
 834
 835 static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
 836                              struct printf_spec spec, const char *fmt)
 837 {
 838         char ip4_addr[sizeof("255.255.255.255")];
 839
 840         ip4_string(ip4_addr, addr, fmt[0] == 'i');
 841
 842         return string(buf, end, ip4_addr, spec);
 843 }
 844
 845 /*
 846  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 847  * by an extra set of alphanumeric characters that are extended format
 848  * specifiers.
 849  *
 850  * Right now we handle:
 851  *
 852  * - 'F' For symbolic function descriptor pointers with offset
 853  * - 'f' For simple symbolic function names without offset
 854  * - 'S' For symbolic direct pointers with offset
 855  * - 's' For symbolic direct pointers without offset
 856  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
 857  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
 858  * - 'M' For a 6-byte MAC address, it prints the address in the
 859  *       usual colon-separated hex notation
 860  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
 861  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
 862  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
 863  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
 864  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
 865  *       IPv6 omits the colons (01020304...0f)
 866  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
 867  * - 'I6c' for IPv6 addresses printed as specified by
 868  *       http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt
 869  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 870  * function pointers are really function descriptors, which contain a
 871  * pointer to the real address.
 872  */
 873 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 874                         struct printf_spec spec)
 875 {
 876         if (!ptr)
 877                 return string(buf, end, "(null)", spec);
 878
 879         switch (*fmt) {
 880         case 'F':
 881         case 'f':
 882                 ptr = dereference_function_descriptor(ptr);
 883         case 's':
 884                 /* Fallthrough */
 885         case 'S':
 886                 return symbol_string(buf, end, ptr, spec, *fmt);
 887         case 'R':
 888         case 'r':
 889                 return resource_string(buf, end, ptr, spec, fmt);
 890         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
 891         case 'm':                       /* Contiguous: 000102030405 */
 892                 return mac_address_string(buf, end, ptr, spec, fmt);
 893         case 'I':                       /* Formatted IP supported
 894                                          * 4:   1.2.3.4
 895                                          * 6:   0001:0203:...:0708
 896                                          * 6c:  1::708 or 1::1.2.3.4
 897                                          */
 898         case 'i':                       /* Contiguous:
 899                                          * 4:   001.002.003.004
 900                                          * 6:   000102...0f
 901                                          */
 902                 switch (fmt[1]) {
 903                 case '6':
 904                         return ip6_addr_string(buf, end, ptr, spec, fmt);
 905                 case '4':
 906                         return ip4_addr_string(buf, end, ptr, spec, fmt);
 907                 }
 908                 break;
 909         }
 910         spec.flags |= SMALL;
 911         if (spec.field_width == -1) {
 912                 spec.field_width = 2*sizeof(void *);
 913                 spec.flags |= ZEROPAD;
 914         }
 915         spec.base = 16;
 916
 917         return number(buf, end, (unsigned long) ptr, spec);
 918 }
 919
 920 /*
 921  * Helper function to decode printf style format.
 922  * Each call decode a token from the format and return the
 923  * number of characters read (or likely the delta where it wants
 924  * to go on the next call).
 925  * The decoded token is returned through the parameters
 926  *
 927  * 'h', 'l', or 'L' for integer fields
 928  * 'z' support added 23/7/1999 S.H.
 929  * 'z' changed to 'Z' --davidm 1/25/99
 930  * 't' added for ptrdiff_t
 931  *
 932  * @fmt: the format string
 933  * @type of the token returned
 934  * @flags: various flags such as +, -, # tokens..
 935  * @field_width: overwritten width
 936  * @base: base of the number (octal, hex, ...)
 937  * @precision: precision of a number
 938  * @qualifier: qualifier of a number (long, size_t, ...)
 939  */
 940 static int format_decode(const char *fmt, struct printf_spec *spec)
 941 {
 942         const char *start = fmt;
 943
 944         /* we finished early by reading the field width */
 945         if (spec->type == FORMAT_TYPE_WIDTH) {
 946                 if (spec->field_width < 0) {
 947                         spec->field_width = -spec->field_width;
 948                         spec->flags |= LEFT;
 949                 }
 950                 spec->type = FORMAT_TYPE_NONE;
 951                 goto precision;
 952         }
 953
 954         /* we finished early by reading the precision */
 955         if (spec->type == FORMAT_TYPE_PRECISION) {
 956                 if (spec->precision < 0)
 957                         spec->precision = 0;
 958
 959                 spec->type = FORMAT_TYPE_NONE;
 960                 goto qualifier;
 961         }
 962
 963         /* By default */
 964         spec->type = FORMAT_TYPE_NONE;
 965
 966         for (; *fmt ; ++fmt) {
 967                 if (*fmt == '%')
 968                         break;
 969         }
 970
 971         /* Return the current non-format string */
 972         if (fmt != start || !*fmt)
 973                 return fmt - start;
 974
 975         /* Process flags */
 976         spec->flags = 0;
 977
 978         while (1) { /* this also skips first '%' */
 979                 bool found = true;
 980
 981                 ++fmt;
 982
 983                 switch (*fmt) {
 984                 case '-': spec->flags |= LEFT;    break;
 985                 case '+': spec->flags |= PLUS;    break;
 986                 case ' ': spec->flags |= SPACE;   break;
 987                 case '#': spec->flags |= SPECIAL; break;
 988                 case '0': spec->flags |= ZEROPAD; break;
 989                 default:  found = false;
 990                 }
 991
 992                 if (!found)
 993                         break;
 994         }
 995
 996         /* get field width */
 997         spec->field_width = -1;
 998
 999         if (isdigit(*fmt))
1000                 spec->field_width = skip_atoi(&fmt);
1001         else if (*fmt == '*') {
1002                 /* it's the next argument */
1003                 spec->type = FORMAT_TYPE_WIDTH;
1004                 return ++fmt - start;
1005         }
1006
1007 precision:
1008         /* get the precision */
1009         spec->precision = -1;
1010         if (*fmt == '.') {
1011                 ++fmt;
1012                 if (isdigit(*fmt)) {
1013                         spec->precision = skip_atoi(&fmt);
1014                         if (spec->precision < 0)
1015                                 spec->precision = 0;
1016                 } else if (*fmt == '*') {
1017                         /* it's the next argument */
1018                         spec->type = FORMAT_TYPE_PRECISION;
1019                         return ++fmt - start;
1020                 }
1021         }
1022
1023 qualifier:
1024         /* get the conversion qualifier */
1025         spec->qualifier = -1;
1026         if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
1027             *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
1028                 spec->qualifier = *fmt++;
1029                 if (unlikely(spec->qualifier == *fmt)) {
1030                         if (spec->qualifier == 'l') {
1031                                 spec->qualifier = 'L';
1032                                 ++fmt;
1033                         } else if (spec->qualifier == 'h') {
1034                                 spec->qualifier = 'H';
1035                                 ++fmt;
1036                         }
1037                 }
1038         }
1039
1040         /* default base */
1041         spec->base = 10;
1042         switch (*fmt) {
1043         case 'c':
1044                 spec->type = FORMAT_TYPE_CHAR;
1045                 return ++fmt - start;
1046
1047         case 's':
1048                 spec->type = FORMAT_TYPE_STR;
1049                 return ++fmt - start;
1050
1051         case 'p':
1052                 spec->type = FORMAT_TYPE_PTR;
1053                 return fmt - start;
1054                 /* skip alnum */
1055
1056         case 'n':
1057                 spec->type = FORMAT_TYPE_NRCHARS;
1058                 return ++fmt - start;
1059
1060         case '%':
1061                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1062                 return ++fmt - start;
1063
1064         /* integer number formats - set up the flags and "break" */
1065         case 'o':
1066                 spec->base = 8;
1067                 break;
1068
1069         case 'x':
1070                 spec->flags |= SMALL;
1071
1072         case 'X':
1073                 spec->base = 16;
1074                 break;
1075
1076         case 'd':
1077         case 'i':
1078                 spec->flags |= SIGN;
1079         case 'u':
1080                 break;
1081
1082         default:
1083                 spec->type = FORMAT_TYPE_INVALID;
1084                 return fmt - start;
1085         }
1086
1087         if (spec->qualifier == 'L')
1088                 spec->type = FORMAT_TYPE_LONG_LONG;
1089         else if (spec->qualifier == 'l') {
1090                 if (spec->flags & SIGN)
1091                         spec->type = FORMAT_TYPE_LONG;
1092                 else
1093                         spec->type = FORMAT_TYPE_ULONG;
1094         } else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
1095                 spec->type = FORMAT_TYPE_SIZE_T;
1096         } else if (spec->qualifier == 't') {
1097                 spec->type = FORMAT_TYPE_PTRDIFF;
1098         } else if (spec->qualifier == 'H') {
1099                 if (spec->flags & SIGN)
1100                         spec->type = FORMAT_TYPE_BYTE;
1101                 else
1102                         spec->type = FORMAT_TYPE_UBYTE;
1103         } else if (spec->qualifier == 'h') {
1104                 if (spec->flags & SIGN)
1105                         spec->type = FORMAT_TYPE_SHORT;
1106                 else
1107                         spec->type = FORMAT_TYPE_USHORT;
1108         } else {
1109                 if (spec->flags & SIGN)
1110                         spec->type = FORMAT_TYPE_INT;
1111                 else
1112                         spec->type = FORMAT_TYPE_UINT;
1113         }
1114
1115         return ++fmt - start;
1116 }
1117
1118 /**
1119  * vsnprintf - Format a string and place it in a buffer
1120  * @buf: The buffer to place the result into
1121  * @size: The size of the buffer, including the trailing null space
1122  * @fmt: The format string to use
1123  * @args: Arguments for the format string
1124  *
1125  * This function follows C99 vsnprintf, but has some extensions:
1126  * %pS output the name of a text symbol with offset
1127  * %ps output the name of a text symbol without offset
1128  * %pF output the name of a function pointer with its offset
1129  * %pf output the name of a function pointer without its offset
1130  * %pR output the address range in a struct resource
1131  * %n is ignored
1132  *
1133  * The return value is the number of characters which would
1134  * be generated for the given input, excluding the trailing
1135  * '\0', as per ISO C99. If you want to have the exact
1136  * number of characters written into @buf as return value
1137  * (not including the trailing '\0'), use vscnprintf(). If the
1138  * return is greater than or equal to @size, the resulting
1139  * string is truncated.
1140  *
1141  * Call this function if you are already dealing with a va_list.
1142  * You probably want snprintf() instead.
1143  */
1144 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1145 {
1146         unsigned long long num;
1147         char *str, *end, c;
1148         int read;
1149         struct printf_spec spec = {0};
1150
1151         /* Reject out-of-range values early.  Large positive sizes are
1152            used for unknown buffer sizes. */
1153         if (WARN_ON_ONCE((int) size < 0))
1154                 return 0;
1155
1156         str = buf;
1157         end = buf + size;
1158
1159         /* Make sure end is always >= buf */
1160         if (end < buf) {
1161                 end = ((void *)-1);
1162                 size = end - buf;
1163         }
1164
1165         while (*fmt) {
1166                 const char *old_fmt = fmt;
1167
1168                 read = format_decode(fmt, &spec);
1169
1170                 fmt += read;
1171
1172                 switch (spec.type) {
1173                 case FORMAT_TYPE_NONE: {
1174                         int copy = read;
1175                         if (str < end) {
1176                                 if (copy > end - str)
1177                                         copy = end - str;
1178                                 memcpy(str, old_fmt, copy);
1179                         }
1180                         str += read;
1181                         break;
1182                 }
1183
1184                 case FORMAT_TYPE_WIDTH:
1185                         spec.field_width = va_arg(args, int);
1186                         break;
1187
1188                 case FORMAT_TYPE_PRECISION:
1189                         spec.precision = va_arg(args, int);
1190                         break;
1191
1192                 case FORMAT_TYPE_CHAR:
1193                         if (!(spec.flags & LEFT)) {
1194                                 while (--spec.field_width > 0) {
1195                                         if (str < end)
1196                                                 *str = ' ';
1197                                         ++str;
1198
1199                                 }
1200                         }
1201                         c = (unsigned char) va_arg(args, int);
1202                         if (str < end)
1203                                 *str = c;
1204                         ++str;
1205                         while (--spec.field_width > 0) {
1206                                 if (str < end)
1207                                         *str = ' ';
1208                                 ++str;
1209                         }
1210                         break;
1211
1212                 case FORMAT_TYPE_STR:
1213                         str = string(str, end, va_arg(args, char *), spec);
1214                         break;
1215
1216                 case FORMAT_TYPE_PTR:
1217                         str = pointer(fmt+1, str, end, va_arg(args, void *),
1218                                       spec);
1219                         while (isalnum(*fmt))
1220                                 fmt++;
1221                         break;
1222
1223                 case FORMAT_TYPE_PERCENT_CHAR:
1224                         if (str < end)
1225                                 *str = '%';
1226                         ++str;
1227                         break;
1228
1229                 case FORMAT_TYPE_INVALID:
1230                         if (str < end)
1231                                 *str = '%';
1232                         ++str;
1233                         break;
1234
1235                 case FORMAT_TYPE_NRCHARS: {
1236                         int qualifier = spec.qualifier;
1237
1238                         if (qualifier == 'l') {
1239                                 long *ip = va_arg(args, long *);
1240                                 *ip = (str - buf);
1241                         } else if (qualifier == 'Z' ||
1242                                         qualifier == 'z') {
1243                                 size_t *ip = va_arg(args, size_t *);
1244                                 *ip = (str - buf);
1245                         } else {
1246                                 int *ip = va_arg(args, int *);
1247                                 *ip = (str - buf);
1248                         }
1249                         break;
1250                 }
1251
1252                 default:
1253                         switch (spec.type) {
1254                         case FORMAT_TYPE_LONG_LONG:
1255                                 num = va_arg(args, long long);
1256                                 break;
1257                         case FORMAT_TYPE_ULONG:
1258                                 num = va_arg(args, unsigned long);
1259                                 break;
1260                         case FORMAT_TYPE_LONG:
1261                                 num = va_arg(args, long);
1262                                 break;
1263                         case FORMAT_TYPE_SIZE_T:
1264                                 num = va_arg(args, size_t);
1265                                 break;
1266                         case FORMAT_TYPE_PTRDIFF:
1267                                 num = va_arg(args, ptrdiff_t);
1268                                 break;
1269                         case FORMAT_TYPE_UBYTE:
1270                                 num = (unsigned char) va_arg(args, int);
1271                                 break;
1272                         case FORMAT_TYPE_BYTE:
1273                                 num = (signed char) va_arg(args, int);
1274                                 break;
1275                         case FORMAT_TYPE_USHORT:
1276                                 num = (unsigned short) va_arg(args, int);
1277                                 break;
1278                         case FORMAT_TYPE_SHORT:
1279                                 num = (short) va_arg(args, int);
1280                                 break;
1281                         case FORMAT_TYPE_INT:
1282                                 num = (int) va_arg(args, int);
1283                                 break;
1284                         default:
1285                                 num = va_arg(args, unsigned int);
1286                         }
1287
1288                         str = number(str, end, num, spec);
1289                 }
1290         }
1291
1292         if (size > 0) {
1293                 if (str < end)
1294                         *str = '\0';
1295                 else
1296                         end[-1] = '\0';
1297         }
1298
1299         /* the trailing null byte doesn't count towards the total */
1300         return str-buf;
1301
1302 }
1303 EXPORT_SYMBOL(vsnprintf);
1304
1305 /**
1306  * vscnprintf - Format a string and place it in a buffer
1307  * @buf: The buffer to place the result into
1308  * @size: The size of the buffer, including the trailing null space
1309  * @fmt: The format string to use
1310  * @args: Arguments for the format string
1311  *
1312  * The return value is the number of characters which have been written into
1313  * the @buf not including the trailing '\0'. If @size is <= 0 the function
1314  * returns 0.
1315  *
1316  * Call this function if you are already dealing with a va_list.
1317  * You probably want scnprintf() instead.
1318  *
1319  * See the vsnprintf() documentation for format string extensions over C99.
1320  */
1321 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1322 {
1323         int i;
1324
1325         i=vsnprintf(buf,size,fmt,args);
1326         return (i >= size) ? (size - 1) : i;
1327 }
1328 EXPORT_SYMBOL(vscnprintf);
1329
1330 /**
1331  * snprintf - Format a string and place it in a buffer
1332  * @buf: The buffer to place the result into
1333  * @size: The size of the buffer, including the trailing null space
1334  * @fmt: The format string to use
1335  * @...: Arguments for the format string
1336  *
1337  * The return value is the number of characters which would be
1338  * generated for the given input, excluding the trailing null,
1339  * as per ISO C99.  If the return is greater than or equal to
1340  * @size, the resulting string is truncated.
1341  *
1342  * See the vsnprintf() documentation for format string extensions over C99.
1343  */
1344 int snprintf(char * buf, size_t size, const char *fmt, ...)
1345 {
1346         va_list args;
1347         int i;
1348
1349         va_start(args, fmt);
1350         i=vsnprintf(buf,size,fmt,args);
1351         va_end(args);
1352         return i;
1353 }
1354 EXPORT_SYMBOL(snprintf);
1355
1356 /**
1357  * scnprintf - Format a string and place it in a buffer
1358  * @buf: The buffer to place the result into
1359  * @size: The size of the buffer, including the trailing null space
1360  * @fmt: The format string to use
1361  * @...: Arguments for the format string
1362  *
1363  * The return value is the number of characters written into @buf not including
1364  * the trailing '\0'. If @size is <= 0 the function returns 0.
1365  */
1366
1367 int scnprintf(char * buf, size_t size, const char *fmt, ...)
1368 {
1369         va_list args;
1370         int i;
1371
1372         va_start(args, fmt);
1373         i = vsnprintf(buf, size, fmt, args);
1374         va_end(args);
1375         return (i >= size) ? (size - 1) : i;
1376 }
1377 EXPORT_SYMBOL(scnprintf);
1378
1379 /**
1380  * vsprintf - Format a string and place it in a buffer
1381  * @buf: The buffer to place the result into
1382  * @fmt: The format string to use
1383  * @args: Arguments for the format string
1384  *
1385  * The function returns the number of characters written
1386  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1387  * buffer overflows.
1388  *
1389  * Call this function if you are already dealing with a va_list.
1390  * You probably want sprintf() instead.
1391  *
1392  * See the vsnprintf() documentation for format string extensions over C99.
1393  */
1394 int vsprintf(char *buf, const char *fmt, va_list args)
1395 {
1396         return vsnprintf(buf, INT_MAX, fmt, args);
1397 }
1398 EXPORT_SYMBOL(vsprintf);
1399
1400 /**
1401  * sprintf - Format a string and place it in a buffer
1402  * @buf: The buffer to place the result into
1403  * @fmt: The format string to use
1404  * @...: Arguments for the format string
1405  *
1406  * The function returns the number of characters written
1407  * into @buf. Use snprintf() or scnprintf() in order to avoid
1408  * buffer overflows.
1409  *
1410  * See the vsnprintf() documentation for format string extensions over C99.
1411  */
1412 int sprintf(char * buf, const char *fmt, ...)
1413 {
1414         va_list args;
1415         int i;
1416
1417         va_start(args, fmt);
1418         i=vsnprintf(buf, INT_MAX, fmt, args);
1419         va_end(args);
1420         return i;
1421 }
1422 EXPORT_SYMBOL(sprintf);
1423
1424 #ifdef CONFIG_BINARY_PRINTF
1425 /*
1426  * bprintf service:
1427  * vbin_printf() - VA arguments to binary data
1428  * bstr_printf() - Binary data to text string
1429  */
1430
1431 /**
1432  * vbin_printf - Parse a format string and place args' binary value in a buffer
1433  * @bin_buf: The buffer to place args' binary value
1434  * @size: The size of the buffer(by words(32bits), not characters)
1435  * @fmt: The format string to use
1436  * @args: Arguments for the format string
1437  *
1438  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1439  * is skiped.
1440  *
1441  * The return value is the number of words(32bits) which would be generated for
1442  * the given input.
1443  *
1444  * NOTE:
1445  * If the return value is greater than @size, the resulting bin_buf is NOT
1446  * valid for bstr_printf().
1447  */
1448 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1449 {
1450         struct printf_spec spec = {0};
1451         char *str, *end;
1452         int read;
1453
1454         str = (char *)bin_buf;
1455         end = (char *)(bin_buf + size);
1456
1457 #define save_arg(type)                                                  \
1458 do {                                                                    \
1459         if (sizeof(type) == 8) {                                        \
1460                 unsigned long long value;                               \
1461                 str = PTR_ALIGN(str, sizeof(u32));                      \
1462                 value = va_arg(args, unsigned long long);               \
1463                 if (str + sizeof(type) <= end) {                        \
1464                         *(u32 *)str = *(u32 *)&value;                   \
1465                         *(u32 *)(str + 4) = *((u32 *)&value + 1);       \
1466                 }                                                       \
1467         } else {                                                        \
1468                 unsigned long value;                                    \
1469                 str = PTR_ALIGN(str, sizeof(type));                     \
1470                 value = va_arg(args, int);                              \
1471                 if (str + sizeof(type) <= end)                          \
1472                         *(typeof(type) *)str = (type)value;             \
1473         }                                                               \
1474         str += sizeof(type);                                            \
1475 } while (0)
1476
1477
1478         while (*fmt) {
1479                 read = format_decode(fmt, &spec);
1480
1481                 fmt += read;
1482
1483                 switch (spec.type) {
1484                 case FORMAT_TYPE_NONE:
1485                         break;
1486
1487                 case FORMAT_TYPE_WIDTH:
1488                 case FORMAT_TYPE_PRECISION:
1489                         save_arg(int);
1490                         break;
1491
1492                 case FORMAT_TYPE_CHAR:
1493                         save_arg(char);
1494                         break;
1495
1496                 case FORMAT_TYPE_STR: {
1497                         const char *save_str = va_arg(args, char *);
1498                         size_t len;
1499
1500                         if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1501                                         || (unsigned long)save_str < PAGE_SIZE)
1502                                 save_str = "(null)";
1503                         len = strlen(save_str) + 1;
1504                         if (str + len < end)
1505                                 memcpy(str, save_str, len);
1506                         str += len;
1507                         break;
1508                 }
1509
1510                 case FORMAT_TYPE_PTR:
1511                         save_arg(void *);
1512                         /* skip all alphanumeric pointer suffixes */
1513                         while (isalnum(*fmt))
1514                                 fmt++;
1515                         break;
1516
1517                 case FORMAT_TYPE_PERCENT_CHAR:
1518                         break;
1519
1520                 case FORMAT_TYPE_INVALID:
1521                         break;
1522
1523                 case FORMAT_TYPE_NRCHARS: {
1524                         /* skip %n 's argument */
1525                         int qualifier = spec.qualifier;
1526                         void *skip_arg;
1527                         if (qualifier == 'l')
1528                                 skip_arg = va_arg(args, long *);
1529                         else if (qualifier == 'Z' || qualifier == 'z')
1530                                 skip_arg = va_arg(args, size_t *);
1531                         else
1532                                 skip_arg = va_arg(args, int *);
1533                         break;
1534                 }
1535
1536                 default:
1537                         switch (spec.type) {
1538
1539                         case FORMAT_TYPE_LONG_LONG:
1540                                 save_arg(long long);
1541                                 break;
1542                         case FORMAT_TYPE_ULONG:
1543                         case FORMAT_TYPE_LONG:
1544                                 save_arg(unsigned long);
1545                                 break;
1546                         case FORMAT_TYPE_SIZE_T:
1547                                 save_arg(size_t);
1548                                 break;
1549                         case FORMAT_TYPE_PTRDIFF:
1550                                 save_arg(ptrdiff_t);
1551                                 break;
1552                         case FORMAT_TYPE_UBYTE:
1553                         case FORMAT_TYPE_BYTE:
1554                                 save_arg(char);
1555                                 break;
1556                         case FORMAT_TYPE_USHORT:
1557                         case FORMAT_TYPE_SHORT:
1558                                 save_arg(short);
1559                                 break;
1560                         default:
1561                                 save_arg(int);
1562                         }
1563                 }
1564         }
1565         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1566
1567 #undef save_arg
1568 }
1569 EXPORT_SYMBOL_GPL(vbin_printf);
1570
1571 /**
1572  * bstr_printf - Format a string from binary arguments and place it in a buffer
1573  * @buf: The buffer to place the result into
1574  * @size: The size of the buffer, including the trailing null space
1575  * @fmt: The format string to use
1576  * @bin_buf: Binary arguments for the format string
1577  *
1578  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1579  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1580  * a binary buffer that generated by vbin_printf.
1581  *
1582  * The format follows C99 vsnprintf, but has some extensions:
1583  *  see vsnprintf comment for details.
1584  *
1585  * The return value is the number of characters which would
1586  * be generated for the given input, excluding the trailing
1587  * '\0', as per ISO C99. If you want to have the exact
1588  * number of characters written into @buf as return value
1589  * (not including the trailing '\0'), use vscnprintf(). If the
1590  * return is greater than or equal to @size, the resulting
1591  * string is truncated.
1592  */
1593 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1594 {
1595         unsigned long long num;
1596         char *str, *end, c;
1597         const char *args = (const char *)bin_buf;
1598
1599         struct printf_spec spec = {0};
1600
1601         if (WARN_ON_ONCE((int) size < 0))
1602                 return 0;
1603
1604         str = buf;
1605         end = buf + size;
1606
1607 #define get_arg(type)                                                   \
1608 ({                                                                      \
1609         typeof(type) value;                                             \
1610         if (sizeof(type) == 8) {                                        \
1611                 args = PTR_ALIGN(args, sizeof(u32));                    \
1612                 *(u32 *)&value = *(u32 *)args;                          \
1613                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
1614         } else {                                                        \
1615                 args = PTR_ALIGN(args, sizeof(type));                   \
1616                 value = *(typeof(type) *)args;                          \
1617         }                                                               \
1618         args += sizeof(type);                                           \
1619         value;                                                          \
1620 })
1621
1622         /* Make sure end is always >= buf */
1623         if (end < buf) {
1624                 end = ((void *)-1);
1625                 size = end - buf;
1626         }
1627
1628         while (*fmt) {
1629                 int read;
1630                 const char *old_fmt = fmt;
1631
1632                 read = format_decode(fmt, &spec);
1633
1634                 fmt += read;
1635
1636                 switch (spec.type) {
1637                 case FORMAT_TYPE_NONE: {
1638                         int copy = read;
1639                         if (str < end) {
1640                                 if (copy > end - str)
1641                                         copy = end - str;
1642                                 memcpy(str, old_fmt, copy);
1643                         }
1644                         str += read;
1645                         break;
1646                 }
1647
1648                 case FORMAT_TYPE_WIDTH:
1649                         spec.field_width = get_arg(int);
1650                         break;
1651
1652                 case FORMAT_TYPE_PRECISION:
1653                         spec.precision = get_arg(int);
1654                         break;
1655
1656                 case FORMAT_TYPE_CHAR:
1657                         if (!(spec.flags & LEFT)) {
1658                                 while (--spec.field_width > 0) {
1659                                         if (str < end)
1660                                                 *str = ' ';
1661                                         ++str;
1662                                 }
1663                         }
1664                         c = (unsigned char) get_arg(char);
1665                         if (str < end)
1666                                 *str = c;
1667                         ++str;
1668                         while (--spec.field_width > 0) {
1669                                 if (str < end)
1670                                         *str = ' ';
1671                                 ++str;
1672                         }
1673                         break;
1674
1675                 case FORMAT_TYPE_STR: {
1676                         const char *str_arg = args;
1677                         size_t len = strlen(str_arg);
1678                         args += len + 1;
1679                         str = string(str, end, (char *)str_arg, spec);
1680                         break;
1681                 }
1682
1683                 case FORMAT_TYPE_PTR:
1684                         str = pointer(fmt+1, str, end, get_arg(void *), spec);
1685                         while (isalnum(*fmt))
1686                                 fmt++;
1687                         break;
1688
1689                 case FORMAT_TYPE_PERCENT_CHAR:
1690                         if (str < end)
1691                                 *str = '%';
1692                         ++str;
1693                         break;
1694
1695                 case FORMAT_TYPE_INVALID:
1696                         if (str < end)
1697                                 *str = '%';
1698                         ++str;
1699                         break;
1700
1701                 case FORMAT_TYPE_NRCHARS:
1702                         /* skip */
1703                         break;
1704
1705                 default:
1706                         switch (spec.type) {
1707
1708                         case FORMAT_TYPE_LONG_LONG:
1709                                 num = get_arg(long long);
1710                                 break;
1711                         case FORMAT_TYPE_ULONG:
1712                                 num = get_arg(unsigned long);
1713                                 break;
1714                         case FORMAT_TYPE_LONG:
1715                                 num = get_arg(unsigned long);
1716                                 break;
1717                         case FORMAT_TYPE_SIZE_T:
1718                                 num = get_arg(size_t);
1719                                 break;
1720                         case FORMAT_TYPE_PTRDIFF:
1721                                 num = get_arg(ptrdiff_t);
1722                                 break;
1723                         case FORMAT_TYPE_UBYTE:
1724                                 num = get_arg(unsigned char);
1725                                 break;
1726                         case FORMAT_TYPE_BYTE:
1727                                 num = get_arg(signed char);
1728                                 break;
1729                         case FORMAT_TYPE_USHORT:
1730                                 num = get_arg(unsigned short);
1731                                 break;
1732                         case FORMAT_TYPE_SHORT:
1733                                 num = get_arg(short);
1734                                 break;
1735                         case FORMAT_TYPE_UINT:
1736                                 num = get_arg(unsigned int);
1737                                 break;
1738                         default:
1739                                 num = get_arg(int);
1740                         }
1741
1742                         str = number(str, end, num, spec);
1743                 }
1744         }
1745
1746         if (size > 0) {
1747                 if (str < end)
1748                         *str = '\0';
1749                 else
1750                         end[-1] = '\0';
1751         }
1752
1753 #undef get_arg
1754
1755         /* the trailing null byte doesn't count towards the total */
1756         return str - buf;
1757 }
1758 EXPORT_SYMBOL_GPL(bstr_printf);
1759
1760 /**
1761  * bprintf - Parse a format string and place args' binary value in a buffer
1762  * @bin_buf: The buffer to place args' binary value
1763  * @size: The size of the buffer(by words(32bits), not characters)
1764  * @fmt: The format string to use
1765  * @...: Arguments for the format string
1766  *
1767  * The function returns the number of words(u32) written
1768  * into @bin_buf.
1769  */
1770 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1771 {
1772         va_list args;
1773         int ret;
1774
1775         va_start(args, fmt);
1776         ret = vbin_printf(bin_buf, size, fmt, args);
1777         va_end(args);
1778         return ret;
1779 }
1780 EXPORT_SYMBOL_GPL(bprintf);
1781
1782 #endif /* CONFIG_BINARY_PRINTF */
1783
1784 /**
1785  * vsscanf - Unformat a buffer into a list of arguments
1786  * @buf:        input buffer
1787  * @fmt:        format of buffer
1788  * @args:       arguments
1789  */
1790 int vsscanf(const char * buf, const char * fmt, va_list args)
1791 {
1792         const char *str = buf;
1793         char *next;
1794         char digit;
1795         int num = 0;
1796         int qualifier;
1797         int base;
1798         int field_width;
1799         int is_sign = 0;
1800
1801         while(*fmt && *str) {
1802                 /* skip any white space in format */
1803                 /* white space in format matchs any amount of
1804                  * white space, including none, in the input.
1805                  */
1806                 if (isspace(*fmt)) {
1807                         while (isspace(*fmt))
1808                                 ++fmt;
1809                         while (isspace(*str))
1810                                 ++str;
1811                 }
1812
1813                 /* anything that is not a conversion must match exactly */
1814                 if (*fmt != '%' && *fmt) {
1815                         if (*fmt++ != *str++)
1816                                 break;
1817                         continue;
1818                 }
1819
1820                 if (!*fmt)
1821                         break;
1822                 ++fmt;
1823
1824                 /* skip this conversion.
1825                  * advance both strings to next white space
1826                  */
1827                 if (*fmt == '*') {
1828                         while (!isspace(*fmt) && *fmt != '%' && *fmt)
1829                                 fmt++;
1830                         while (!isspace(*str) && *str)
1831                                 str++;
1832                         continue;
1833                 }
1834
1835                 /* get field width */
1836                 field_width = -1;
1837                 if (isdigit(*fmt))
1838                         field_width = skip_atoi(&fmt);
1839
1840                 /* get conversion qualifier */
1841                 qualifier = -1;
1842                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
1843                     *fmt == 'Z' || *fmt == 'z') {
1844                         qualifier = *fmt++;
1845                         if (unlikely(qualifier == *fmt)) {
1846                                 if (qualifier == 'h') {
1847                                         qualifier = 'H';
1848                                         fmt++;
1849                                 } else if (qualifier == 'l') {
1850                                         qualifier = 'L';
1851                                         fmt++;
1852                                 }
1853                         }
1854                 }
1855                 base = 10;
1856                 is_sign = 0;
1857
1858                 if (!*fmt || !*str)
1859                         break;
1860
1861                 switch(*fmt++) {
1862                 case 'c':
1863                 {
1864                         char *s = (char *) va_arg(args,char*);
1865                         if (field_width == -1)
1866                                 field_width = 1;
1867                         do {
1868                                 *s++ = *str++;
1869                         } while (--field_width > 0 && *str);
1870                         num++;
1871                 }
1872                 continue;
1873                 case 's':
1874                 {
1875                         char *s = (char *) va_arg(args, char *);
1876                         if(field_width == -1)
1877                                 field_width = INT_MAX;
1878                         /* first, skip leading white space in buffer */
1879                         while (isspace(*str))
1880                                 str++;
1881
1882                         /* now copy until next white space */
1883                         while (*str && !isspace(*str) && field_width--) {
1884                                 *s++ = *str++;
1885                         }
1886                         *s = '\0';
1887                         num++;
1888                 }
1889                 continue;
1890                 case 'n':
1891                         /* return number of characters read so far */
1892                 {
1893                         int *i = (int *)va_arg(args,int*);
1894                         *i = str - buf;
1895                 }
1896                 continue;
1897                 case 'o':
1898                         base = 8;
1899                         break;
1900                 case 'x':
1901                 case 'X':
1902                         base = 16;
1903                         break;
1904                 case 'i':
1905                         base = 0;
1906                 case 'd':
1907                         is_sign = 1;
1908                 case 'u':
1909                         break;
1910                 case '%':
1911                         /* looking for '%' in str */
1912                         if (*str++ != '%')
1913                                 return num;
1914                         continue;
1915                 default:
1916                         /* invalid format; stop here */
1917                         return num;
1918                 }
1919
1920                 /* have some sort of integer conversion.
1921                  * first, skip white space in buffer.
1922                  */
1923                 while (isspace(*str))
1924                         str++;
1925
1926                 digit = *str;
1927                 if (is_sign && digit == '-')
1928                         digit = *(str + 1);
1929
1930                 if (!digit
1931                     || (base == 16 && !isxdigit(digit))
1932                     || (base == 10 && !isdigit(digit))
1933                     || (base == 8 && (!isdigit(digit) || digit > '7'))
1934                     || (base == 0 && !isdigit(digit)))
1935                                 break;
1936
1937                 switch(qualifier) {
1938                 case 'H':       /* that's 'hh' in format */
1939                         if (is_sign) {
1940                                 signed char *s = (signed char *) va_arg(args,signed char *);
1941                                 *s = (signed char) simple_strtol(str,&next,base);
1942                         } else {
1943                                 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
1944                                 *s = (unsigned char) simple_strtoul(str, &next, base);
1945                         }
1946                         break;
1947                 case 'h':
1948                         if (is_sign) {
1949                                 short *s = (short *) va_arg(args,short *);
1950                                 *s = (short) simple_strtol(str,&next,base);
1951                         } else {
1952                                 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
1953                                 *s = (unsigned short) simple_strtoul(str, &next, base);
1954                         }
1955                         break;
1956                 case 'l':
1957                         if (is_sign) {
1958                                 long *l = (long *) va_arg(args,long *);
1959                                 *l = simple_strtol(str,&next,base);
1960                         } else {
1961                                 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
1962                                 *l = simple_strtoul(str,&next,base);
1963                         }
1964                         break;
1965                 case 'L':
1966                         if (is_sign) {
1967                                 long long *l = (long long*) va_arg(args,long long *);
1968                                 *l = simple_strtoll(str,&next,base);
1969                         } else {
1970                                 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
1971                                 *l = simple_strtoull(str,&next,base);
1972                         }
1973                         break;
1974                 case 'Z':
1975                 case 'z':
1976                 {
1977                         size_t *s = (size_t*) va_arg(args,size_t*);
1978                         *s = (size_t) simple_strtoul(str,&next,base);
1979                 }
1980                 break;
1981                 default:
1982                         if (is_sign) {
1983                                 int *i = (int *) va_arg(args, int*);
1984                                 *i = (int) simple_strtol(str,&next,base);
1985                         } else {
1986                                 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
1987                                 *i = (unsigned int) simple_strtoul(str,&next,base);
1988                         }
1989                         break;
1990                 }
1991                 num++;
1992
1993                 if (!next)
1994                         break;
1995                 str = next;
1996         }
1997
1998         /*
1999          * Now we've come all the way through so either the input string or the
2000          * format ended. In the former case, there can be a %n at the current
2001          * position in the format that needs to be filled.
2002          */
2003         if (*fmt == '%' && *(fmt + 1) == 'n') {
2004                 int *p = (int *)va_arg(args, int *);
2005                 *p = str - buf;
2006         }
2007
2008         return num;
2009 }
2010 EXPORT_SYMBOL(vsscanf);
2011
2012 /**
2013  * sscanf - Unformat a buffer into a list of arguments
2014  * @buf:        input buffer
2015  * @fmt:        formatting of buffer
2016  * @...:        resulting arguments
2017  */
2018 int sscanf(const char * buf, const char * fmt, ...)
2019 {
2020         va_list args;
2021         int i;
2022
2023         va_start(args,fmt);
2024         i = vsscanf(buf,fmt,args);
2025         va_end(args);
2026         return i;
2027 }
2028 EXPORT_SYMBOL(sscanf);