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, 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)
 599 {
 600 #ifndef IO_RSRC_PRINTK_SIZE
 601 #define IO_RSRC_PRINTK_SIZE     4
 602 #endif
 603
 604 #ifndef MEM_RSRC_PRINTK_SIZE
 605 #define MEM_RSRC_PRINTK_SIZE    8
 606 #endif
 607         struct printf_spec num_spec = {
 608                 .base = 16,
 609                 .precision = -1,
 610                 .flags = SPECIAL | SMALL | ZEROPAD,
 611         };
 612         /* room for the actual numbers, the two "0x", -, [, ] and the final zero */
 613         char sym[4*sizeof(resource_size_t) + 8];
 614         char *p = sym, *pend = sym + sizeof(sym);
 615         int size = -1;
 616
 617         if (res->flags & IORESOURCE_IO)
 618                 size = IO_RSRC_PRINTK_SIZE;
 619         else if (res->flags & IORESOURCE_MEM)
 620                 size = MEM_RSRC_PRINTK_SIZE;
 621
 622         *p++ = '[';
 623         num_spec.field_width = size;
 624         p = number(p, pend, res->start, num_spec);
 625         *p++ = '-';
 626         p = number(p, pend, res->end, num_spec);
 627         *p++ = ']';
 628         *p = 0;
 629
 630         return string(buf, end, sym, spec);
 631 }
 632
 633 static char *mac_address_string(char *buf, char *end, u8 *addr,
 634                                 struct printf_spec spec, const char *fmt)
 635 {
 636         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
 637         char *p = mac_addr;
 638         int i;
 639
 640         for (i = 0; i < 6; i++) {
 641                 p = pack_hex_byte(p, addr[i]);
 642                 if (fmt[0] == 'M' && i != 5)
 643                         *p++ = ':';
 644         }
 645         *p = '\0';
 646
 647         return string(buf, end, mac_addr, spec);
 648 }
 649
 650 static char *ip4_string(char *p, const u8 *addr, bool leading_zeros)
 651 {
 652         int i;
 653
 654         for (i = 0; i < 4; i++) {
 655                 char temp[3];   /* hold each IP quad in reverse order */
 656                 int digits = put_dec_trunc(temp, addr[i]) - temp;
 657                 if (leading_zeros) {
 658                         if (digits < 3)
 659                                 *p++ = '0';
 660                         if (digits < 2)
 661                                 *p++ = '0';
 662                 }
 663                 /* reverse the digits in the quad */
 664                 while (digits--)
 665                         *p++ = temp[digits];
 666                 if (i < 3)
 667                         *p++ = '.';
 668         }
 669
 670         *p = '\0';
 671         return p;
 672 }
 673
 674 static char *ip6_compressed_string(char *p, const char *addr)
 675 {
 676         int i;
 677         int j;
 678         int range;
 679         unsigned char zerolength[8];
 680         int longest = 1;
 681         int colonpos = -1;
 682         u16 word;
 683         u8 hi;
 684         u8 lo;
 685         bool needcolon = false;
 686         bool useIPv4;
 687         struct in6_addr in6;
 688
 689         memcpy(&in6, addr, sizeof(struct in6_addr));
 690
 691         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
 692
 693         memset(zerolength, 0, sizeof(zerolength));
 694
 695         if (useIPv4)
 696                 range = 6;
 697         else
 698                 range = 8;
 699
 700         /* find position of longest 0 run */
 701         for (i = 0; i < range; i++) {
 702                 for (j = i; j < range; j++) {
 703                         if (in6.s6_addr16[j] != 0)
 704                                 break;
 705                         zerolength[i]++;
 706                 }
 707         }
 708         for (i = 0; i < range; i++) {
 709                 if (zerolength[i] > longest) {
 710                         longest = zerolength[i];
 711                         colonpos = i;
 712                 }
 713         }
 714
 715         /* emit address */
 716         for (i = 0; i < range; i++) {
 717                 if (i == colonpos) {
 718                         if (needcolon || i == 0)
 719                                 *p++ = ':';
 720                         *p++ = ':';
 721                         needcolon = false;
 722                         i += longest - 1;
 723                         continue;
 724                 }
 725                 if (needcolon) {
 726                         *p++ = ':';
 727                         needcolon = false;
 728                 }
 729                 /* hex u16 without leading 0s */
 730                 word = ntohs(in6.s6_addr16[i]);
 731                 hi = word >> 8;
 732                 lo = word & 0xff;
 733                 if (hi) {
 734                         if (hi > 0x0f)
 735                                 p = pack_hex_byte(p, hi);
 736                         else
 737                                 *p++ = hex_asc_lo(hi);
 738                 }
 739                 if (hi || lo > 0x0f)
 740                         p = pack_hex_byte(p, lo);
 741                 else
 742                         *p++ = hex_asc_lo(lo);
 743                 needcolon = true;
 744         }
 745
 746         if (useIPv4) {
 747                 if (needcolon)
 748                         *p++ = ':';
 749                 p = ip4_string(p, &in6.s6_addr[12], false);
 750         }
 751
 752         *p = '\0';
 753         return p;
 754 }
 755
 756 static char *ip6_string(char *p, const char *addr, const char *fmt)
 757 {
 758         int i;
 759         for (i = 0; i < 8; i++) {
 760                 p = pack_hex_byte(p, *addr++);
 761                 p = pack_hex_byte(p, *addr++);
 762                 if (fmt[0] == 'I' && i != 7)
 763                         *p++ = ':';
 764         }
 765
 766         *p = '\0';
 767         return p;
 768 }
 769
 770 static char *ip6_addr_string(char *buf, char *end, const u8 *addr,
 771                              struct printf_spec spec, const char *fmt)
 772 {
 773         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
 774
 775         if (fmt[0] == 'I' && fmt[2] == 'c')
 776                 ip6_compressed_string(ip6_addr, addr);
 777         else
 778                 ip6_string(ip6_addr, addr, fmt);
 779
 780         return string(buf, end, ip6_addr, spec);
 781 }
 782
 783 static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
 784                              struct printf_spec spec, const char *fmt)
 785 {
 786         char ip4_addr[sizeof("255.255.255.255")];
 787
 788         ip4_string(ip4_addr, addr, fmt[0] == 'i');
 789
 790         return string(buf, end, ip4_addr, spec);
 791 }
 792
 793 /*
 794  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 795  * by an extra set of alphanumeric characters that are extended format
 796  * specifiers.
 797  *
 798  * Right now we handle:
 799  *
 800  * - 'F' For symbolic function descriptor pointers with offset
 801  * - 'f' For simple symbolic function names without offset
 802  * - 'S' For symbolic direct pointers with offset
 803  * - 's' For symbolic direct pointers without offset
 804  * - 'R' For a struct resource pointer, it prints the range of
 805  *       addresses (not the name nor the flags)
 806  * - 'M' For a 6-byte MAC address, it prints the address in the
 807  *       usual colon-separated hex notation
 808  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
 809  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
 810  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
 811  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
 812  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
 813  *       IPv6 omits the colons (01020304...0f)
 814  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
 815  * - 'I6c' for IPv6 addresses printed as specified by
 816  *       http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt
 817  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 818  * function pointers are really function descriptors, which contain a
 819  * pointer to the real address.
 820  */
 821 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 822                         struct printf_spec spec)
 823 {
 824         if (!ptr)
 825                 return string(buf, end, "(null)", spec);
 826
 827         switch (*fmt) {
 828         case 'F':
 829         case 'f':
 830                 ptr = dereference_function_descriptor(ptr);
 831         case 's':
 832                 /* Fallthrough */
 833         case 'S':
 834                 return symbol_string(buf, end, ptr, spec, *fmt);
 835         case 'R':
 836                 return resource_string(buf, end, ptr, spec);
 837         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
 838         case 'm':                       /* Contiguous: 000102030405 */
 839                 return mac_address_string(buf, end, ptr, spec, fmt);
 840         case 'I':                       /* Formatted IP supported
 841                                          * 4:   1.2.3.4
 842                                          * 6:   0001:0203:...:0708
 843                                          * 6c:  1::708 or 1::1.2.3.4
 844                                          */
 845         case 'i':                       /* Contiguous:
 846                                          * 4:   001.002.003.004
 847                                          * 6:   000102...0f
 848                                          */
 849                 switch (fmt[1]) {
 850                 case '6':
 851                         return ip6_addr_string(buf, end, ptr, spec, fmt);
 852                 case '4':
 853                         return ip4_addr_string(buf, end, ptr, spec, fmt);
 854                 }
 855                 break;
 856         }
 857         spec.flags |= SMALL;
 858         if (spec.field_width == -1) {
 859                 spec.field_width = 2*sizeof(void *);
 860                 spec.flags |= ZEROPAD;
 861         }
 862         spec.base = 16;
 863
 864         return number(buf, end, (unsigned long) ptr, spec);
 865 }
 866
 867 /*
 868  * Helper function to decode printf style format.
 869  * Each call decode a token from the format and return the
 870  * number of characters read (or likely the delta where it wants
 871  * to go on the next call).
 872  * The decoded token is returned through the parameters
 873  *
 874  * 'h', 'l', or 'L' for integer fields
 875  * 'z' support added 23/7/1999 S.H.
 876  * 'z' changed to 'Z' --davidm 1/25/99
 877  * 't' added for ptrdiff_t
 878  *
 879  * @fmt: the format string
 880  * @type of the token returned
 881  * @flags: various flags such as +, -, # tokens..
 882  * @field_width: overwritten width
 883  * @base: base of the number (octal, hex, ...)
 884  * @precision: precision of a number
 885  * @qualifier: qualifier of a number (long, size_t, ...)
 886  */
 887 static int format_decode(const char *fmt, struct printf_spec *spec)
 888 {
 889         const char *start = fmt;
 890
 891         /* we finished early by reading the field width */
 892         if (spec->type == FORMAT_TYPE_WIDTH) {
 893                 if (spec->field_width < 0) {
 894                         spec->field_width = -spec->field_width;
 895                         spec->flags |= LEFT;
 896                 }
 897                 spec->type = FORMAT_TYPE_NONE;
 898                 goto precision;
 899         }
 900
 901         /* we finished early by reading the precision */
 902         if (spec->type == FORMAT_TYPE_PRECISION) {
 903                 if (spec->precision < 0)
 904                         spec->precision = 0;
 905
 906                 spec->type = FORMAT_TYPE_NONE;
 907                 goto qualifier;
 908         }
 909
 910         /* By default */
 911         spec->type = FORMAT_TYPE_NONE;
 912
 913         for (; *fmt ; ++fmt) {
 914                 if (*fmt == '%')
 915                         break;
 916         }
 917
 918         /* Return the current non-format string */
 919         if (fmt != start || !*fmt)
 920                 return fmt - start;
 921
 922         /* Process flags */
 923         spec->flags = 0;
 924
 925         while (1) { /* this also skips first '%' */
 926                 bool found = true;
 927
 928                 ++fmt;
 929
 930                 switch (*fmt) {
 931                 case '-': spec->flags |= LEFT;    break;
 932                 case '+': spec->flags |= PLUS;    break;
 933                 case ' ': spec->flags |= SPACE;   break;
 934                 case '#': spec->flags |= SPECIAL; break;
 935                 case '0': spec->flags |= ZEROPAD; break;
 936                 default:  found = false;
 937                 }
 938
 939                 if (!found)
 940                         break;
 941         }
 942
 943         /* get field width */
 944         spec->field_width = -1;
 945
 946         if (isdigit(*fmt))
 947                 spec->field_width = skip_atoi(&fmt);
 948         else if (*fmt == '*') {
 949                 /* it's the next argument */
 950                 spec->type = FORMAT_TYPE_WIDTH;
 951                 return ++fmt - start;
 952         }
 953
 954 precision:
 955         /* get the precision */
 956         spec->precision = -1;
 957         if (*fmt == '.') {
 958                 ++fmt;
 959                 if (isdigit(*fmt)) {
 960                         spec->precision = skip_atoi(&fmt);
 961                         if (spec->precision < 0)
 962                                 spec->precision = 0;
 963                 } else if (*fmt == '*') {
 964                         /* it's the next argument */
 965                         spec->type = FORMAT_TYPE_PRECISION;
 966                         return ++fmt - start;
 967                 }
 968         }
 969
 970 qualifier:
 971         /* get the conversion qualifier */
 972         spec->qualifier = -1;
 973         if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 974             *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
 975                 spec->qualifier = *fmt++;
 976                 if (unlikely(spec->qualifier == *fmt)) {
 977                         if (spec->qualifier == 'l') {
 978                                 spec->qualifier = 'L';
 979                                 ++fmt;
 980                         } else if (spec->qualifier == 'h') {
 981                                 spec->qualifier = 'H';
 982                                 ++fmt;
 983                         }
 984                 }
 985         }
 986
 987         /* default base */
 988         spec->base = 10;
 989         switch (*fmt) {
 990         case 'c':
 991                 spec->type = FORMAT_TYPE_CHAR;
 992                 return ++fmt - start;
 993
 994         case 's':
 995                 spec->type = FORMAT_TYPE_STR;
 996                 return ++fmt - start;
 997
 998         case 'p':
 999                 spec->type = FORMAT_TYPE_PTR;
1000                 return fmt - start;
1001                 /* skip alnum */
1002
1003         case 'n':
1004                 spec->type = FORMAT_TYPE_NRCHARS;
1005                 return ++fmt - start;
1006
1007         case '%':
1008                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1009                 return ++fmt - start;
1010
1011         /* integer number formats - set up the flags and "break" */
1012         case 'o':
1013                 spec->base = 8;
1014                 break;
1015
1016         case 'x':
1017                 spec->flags |= SMALL;
1018
1019         case 'X':
1020                 spec->base = 16;
1021                 break;
1022
1023         case 'd':
1024         case 'i':
1025                 spec->flags |= SIGN;
1026         case 'u':
1027                 break;
1028
1029         default:
1030                 spec->type = FORMAT_TYPE_INVALID;
1031                 return fmt - start;
1032         }
1033
1034         if (spec->qualifier == 'L')
1035                 spec->type = FORMAT_TYPE_LONG_LONG;
1036         else if (spec->qualifier == 'l') {
1037                 if (spec->flags & SIGN)
1038                         spec->type = FORMAT_TYPE_LONG;
1039                 else
1040                         spec->type = FORMAT_TYPE_ULONG;
1041         } else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
1042                 spec->type = FORMAT_TYPE_SIZE_T;
1043         } else if (spec->qualifier == 't') {
1044                 spec->type = FORMAT_TYPE_PTRDIFF;
1045         } else if (spec->qualifier == 'H') {
1046                 if (spec->flags & SIGN)
1047                         spec->type = FORMAT_TYPE_BYTE;
1048                 else
1049                         spec->type = FORMAT_TYPE_UBYTE;
1050         } else if (spec->qualifier == 'h') {
1051                 if (spec->flags & SIGN)
1052                         spec->type = FORMAT_TYPE_SHORT;
1053                 else
1054                         spec->type = FORMAT_TYPE_USHORT;
1055         } else {
1056                 if (spec->flags & SIGN)
1057                         spec->type = FORMAT_TYPE_INT;
1058                 else
1059                         spec->type = FORMAT_TYPE_UINT;
1060         }
1061
1062         return ++fmt - start;
1063 }
1064
1065 /**
1066  * vsnprintf - Format a string and place it in a buffer
1067  * @buf: The buffer to place the result into
1068  * @size: The size of the buffer, including the trailing null space
1069  * @fmt: The format string to use
1070  * @args: Arguments for the format string
1071  *
1072  * This function follows C99 vsnprintf, but has some extensions:
1073  * %pS output the name of a text symbol with offset
1074  * %ps output the name of a text symbol without offset
1075  * %pF output the name of a function pointer with its offset
1076  * %pf output the name of a function pointer without its offset
1077  * %pR output the address range in a struct resource
1078  * %n is ignored
1079  *
1080  * The return value is the number of characters which would
1081  * be generated for the given input, excluding the trailing
1082  * '\0', as per ISO C99. If you want to have the exact
1083  * number of characters written into @buf as return value
1084  * (not including the trailing '\0'), use vscnprintf(). If the
1085  * return is greater than or equal to @size, the resulting
1086  * string is truncated.
1087  *
1088  * Call this function if you are already dealing with a va_list.
1089  * You probably want snprintf() instead.
1090  */
1091 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1092 {
1093         unsigned long long num;
1094         char *str, *end, c;
1095         int read;
1096         struct printf_spec spec = {0};
1097
1098         /* Reject out-of-range values early.  Large positive sizes are
1099            used for unknown buffer sizes. */
1100         if (WARN_ON_ONCE((int) size < 0))
1101                 return 0;
1102
1103         str = buf;
1104         end = buf + size;
1105
1106         /* Make sure end is always >= buf */
1107         if (end < buf) {
1108                 end = ((void *)-1);
1109                 size = end - buf;
1110         }
1111
1112         while (*fmt) {
1113                 const char *old_fmt = fmt;
1114
1115                 read = format_decode(fmt, &spec);
1116
1117                 fmt += read;
1118
1119                 switch (spec.type) {
1120                 case FORMAT_TYPE_NONE: {
1121                         int copy = read;
1122                         if (str < end) {
1123                                 if (copy > end - str)
1124                                         copy = end - str;
1125                                 memcpy(str, old_fmt, copy);
1126                         }
1127                         str += read;
1128                         break;
1129                 }
1130
1131                 case FORMAT_TYPE_WIDTH:
1132                         spec.field_width = va_arg(args, int);
1133                         break;
1134
1135                 case FORMAT_TYPE_PRECISION:
1136                         spec.precision = va_arg(args, int);
1137                         break;
1138
1139                 case FORMAT_TYPE_CHAR:
1140                         if (!(spec.flags & LEFT)) {
1141                                 while (--spec.field_width > 0) {
1142                                         if (str < end)
1143                                                 *str = ' ';
1144                                         ++str;
1145
1146                                 }
1147                         }
1148                         c = (unsigned char) va_arg(args, int);
1149                         if (str < end)
1150                                 *str = c;
1151                         ++str;
1152                         while (--spec.field_width > 0) {
1153                                 if (str < end)
1154                                         *str = ' ';
1155                                 ++str;
1156                         }
1157                         break;
1158
1159                 case FORMAT_TYPE_STR:
1160                         str = string(str, end, va_arg(args, char *), spec);
1161                         break;
1162
1163                 case FORMAT_TYPE_PTR:
1164                         str = pointer(fmt+1, str, end, va_arg(args, void *),
1165                                       spec);
1166                         while (isalnum(*fmt))
1167                                 fmt++;
1168                         break;
1169
1170                 case FORMAT_TYPE_PERCENT_CHAR:
1171                         if (str < end)
1172                                 *str = '%';
1173                         ++str;
1174                         break;
1175
1176                 case FORMAT_TYPE_INVALID:
1177                         if (str < end)
1178                                 *str = '%';
1179                         ++str;
1180                         break;
1181
1182                 case FORMAT_TYPE_NRCHARS: {
1183                         int qualifier = spec.qualifier;
1184
1185                         if (qualifier == 'l') {
1186                                 long *ip = va_arg(args, long *);
1187                                 *ip = (str - buf);
1188                         } else if (qualifier == 'Z' ||
1189                                         qualifier == 'z') {
1190                                 size_t *ip = va_arg(args, size_t *);
1191                                 *ip = (str - buf);
1192                         } else {
1193                                 int *ip = va_arg(args, int *);
1194                                 *ip = (str - buf);
1195                         }
1196                         break;
1197                 }
1198
1199                 default:
1200                         switch (spec.type) {
1201                         case FORMAT_TYPE_LONG_LONG:
1202                                 num = va_arg(args, long long);
1203                                 break;
1204                         case FORMAT_TYPE_ULONG:
1205                                 num = va_arg(args, unsigned long);
1206                                 break;
1207                         case FORMAT_TYPE_LONG:
1208                                 num = va_arg(args, long);
1209                                 break;
1210                         case FORMAT_TYPE_SIZE_T:
1211                                 num = va_arg(args, size_t);
1212                                 break;
1213                         case FORMAT_TYPE_PTRDIFF:
1214                                 num = va_arg(args, ptrdiff_t);
1215                                 break;
1216                         case FORMAT_TYPE_UBYTE:
1217                                 num = (unsigned char) va_arg(args, int);
1218                                 break;
1219                         case FORMAT_TYPE_BYTE:
1220                                 num = (signed char) va_arg(args, int);
1221                                 break;
1222                         case FORMAT_TYPE_USHORT:
1223                                 num = (unsigned short) va_arg(args, int);
1224                                 break;
1225                         case FORMAT_TYPE_SHORT:
1226                                 num = (short) va_arg(args, int);
1227                                 break;
1228                         case FORMAT_TYPE_INT:
1229                                 num = (int) va_arg(args, int);
1230                                 break;
1231                         default:
1232                                 num = va_arg(args, unsigned int);
1233                         }
1234
1235                         str = number(str, end, num, spec);
1236                 }
1237         }
1238
1239         if (size > 0) {
1240                 if (str < end)
1241                         *str = '\0';
1242                 else
1243                         end[-1] = '\0';
1244         }
1245
1246         /* the trailing null byte doesn't count towards the total */
1247         return str-buf;
1248
1249 }
1250 EXPORT_SYMBOL(vsnprintf);
1251
1252 /**
1253  * vscnprintf - Format a string and place it in a buffer
1254  * @buf: The buffer to place the result into
1255  * @size: The size of the buffer, including the trailing null space
1256  * @fmt: The format string to use
1257  * @args: Arguments for the format string
1258  *
1259  * The return value is the number of characters which have been written into
1260  * the @buf not including the trailing '\0'. If @size is <= 0 the function
1261  * returns 0.
1262  *
1263  * Call this function if you are already dealing with a va_list.
1264  * You probably want scnprintf() instead.
1265  *
1266  * See the vsnprintf() documentation for format string extensions over C99.
1267  */
1268 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1269 {
1270         int i;
1271
1272         i=vsnprintf(buf,size,fmt,args);
1273         return (i >= size) ? (size - 1) : i;
1274 }
1275 EXPORT_SYMBOL(vscnprintf);
1276
1277 /**
1278  * snprintf - Format a string and place it in a buffer
1279  * @buf: The buffer to place the result into
1280  * @size: The size of the buffer, including the trailing null space
1281  * @fmt: The format string to use
1282  * @...: Arguments for the format string
1283  *
1284  * The return value is the number of characters which would be
1285  * generated for the given input, excluding the trailing null,
1286  * as per ISO C99.  If the return is greater than or equal to
1287  * @size, the resulting string is truncated.
1288  *
1289  * See the vsnprintf() documentation for format string extensions over C99.
1290  */
1291 int snprintf(char * buf, size_t size, const char *fmt, ...)
1292 {
1293         va_list args;
1294         int i;
1295
1296         va_start(args, fmt);
1297         i=vsnprintf(buf,size,fmt,args);
1298         va_end(args);
1299         return i;
1300 }
1301 EXPORT_SYMBOL(snprintf);
1302
1303 /**
1304  * scnprintf - Format a string and place it in a buffer
1305  * @buf: The buffer to place the result into
1306  * @size: The size of the buffer, including the trailing null space
1307  * @fmt: The format string to use
1308  * @...: Arguments for the format string
1309  *
1310  * The return value is the number of characters written into @buf not including
1311  * the trailing '\0'. If @size is <= 0 the function returns 0.
1312  */
1313
1314 int scnprintf(char * buf, size_t size, const char *fmt, ...)
1315 {
1316         va_list args;
1317         int i;
1318
1319         va_start(args, fmt);
1320         i = vsnprintf(buf, size, fmt, args);
1321         va_end(args);
1322         return (i >= size) ? (size - 1) : i;
1323 }
1324 EXPORT_SYMBOL(scnprintf);
1325
1326 /**
1327  * vsprintf - Format a string and place it in a buffer
1328  * @buf: The buffer to place the result into
1329  * @fmt: The format string to use
1330  * @args: Arguments for the format string
1331  *
1332  * The function returns the number of characters written
1333  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1334  * buffer overflows.
1335  *
1336  * Call this function if you are already dealing with a va_list.
1337  * You probably want sprintf() instead.
1338  *
1339  * See the vsnprintf() documentation for format string extensions over C99.
1340  */
1341 int vsprintf(char *buf, const char *fmt, va_list args)
1342 {
1343         return vsnprintf(buf, INT_MAX, fmt, args);
1344 }
1345 EXPORT_SYMBOL(vsprintf);
1346
1347 /**
1348  * sprintf - Format a string and place it in a buffer
1349  * @buf: The buffer to place the result into
1350  * @fmt: The format string to use
1351  * @...: Arguments for the format string
1352  *
1353  * The function returns the number of characters written
1354  * into @buf. Use snprintf() or scnprintf() in order to avoid
1355  * buffer overflows.
1356  *
1357  * See the vsnprintf() documentation for format string extensions over C99.
1358  */
1359 int sprintf(char * buf, const char *fmt, ...)
1360 {
1361         va_list args;
1362         int i;
1363
1364         va_start(args, fmt);
1365         i=vsnprintf(buf, INT_MAX, fmt, args);
1366         va_end(args);
1367         return i;
1368 }
1369 EXPORT_SYMBOL(sprintf);
1370
1371 #ifdef CONFIG_BINARY_PRINTF
1372 /*
1373  * bprintf service:
1374  * vbin_printf() - VA arguments to binary data
1375  * bstr_printf() - Binary data to text string
1376  */
1377
1378 /**
1379  * vbin_printf - Parse a format string and place args' binary value in a buffer
1380  * @bin_buf: The buffer to place args' binary value
1381  * @size: The size of the buffer(by words(32bits), not characters)
1382  * @fmt: The format string to use
1383  * @args: Arguments for the format string
1384  *
1385  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1386  * is skiped.
1387  *
1388  * The return value is the number of words(32bits) which would be generated for
1389  * the given input.
1390  *
1391  * NOTE:
1392  * If the return value is greater than @size, the resulting bin_buf is NOT
1393  * valid for bstr_printf().
1394  */
1395 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1396 {
1397         struct printf_spec spec = {0};
1398         char *str, *end;
1399         int read;
1400
1401         str = (char *)bin_buf;
1402         end = (char *)(bin_buf + size);
1403
1404 #define save_arg(type)                                                  \
1405 do {                                                                    \
1406         if (sizeof(type) == 8) {                                        \
1407                 unsigned long long value;                               \
1408                 str = PTR_ALIGN(str, sizeof(u32));                      \
1409                 value = va_arg(args, unsigned long long);               \
1410                 if (str + sizeof(type) <= end) {                        \
1411                         *(u32 *)str = *(u32 *)&value;                   \
1412                         *(u32 *)(str + 4) = *((u32 *)&value + 1);       \
1413                 }                                                       \
1414         } else {                                                        \
1415                 unsigned long value;                                    \
1416                 str = PTR_ALIGN(str, sizeof(type));                     \
1417                 value = va_arg(args, int);                              \
1418                 if (str + sizeof(type) <= end)                          \
1419                         *(typeof(type) *)str = (type)value;             \
1420         }                                                               \
1421         str += sizeof(type);                                            \
1422 } while (0)
1423
1424
1425         while (*fmt) {
1426                 read = format_decode(fmt, &spec);
1427
1428                 fmt += read;
1429
1430                 switch (spec.type) {
1431                 case FORMAT_TYPE_NONE:
1432                         break;
1433
1434                 case FORMAT_TYPE_WIDTH:
1435                 case FORMAT_TYPE_PRECISION:
1436                         save_arg(int);
1437                         break;
1438
1439                 case FORMAT_TYPE_CHAR:
1440                         save_arg(char);
1441                         break;
1442
1443                 case FORMAT_TYPE_STR: {
1444                         const char *save_str = va_arg(args, char *);
1445                         size_t len;
1446                         if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1447                                         || (unsigned long)save_str < PAGE_SIZE)
1448                                 save_str = "<NULL>";
1449                         len = strlen(save_str);
1450                         if (str + len + 1 < end)
1451                                 memcpy(str, save_str, len + 1);
1452                         str += len + 1;
1453                         break;
1454                 }
1455
1456                 case FORMAT_TYPE_PTR:
1457                         save_arg(void *);
1458                         /* skip all alphanumeric pointer suffixes */
1459                         while (isalnum(*fmt))
1460                                 fmt++;
1461                         break;
1462
1463                 case FORMAT_TYPE_PERCENT_CHAR:
1464                         break;
1465
1466                 case FORMAT_TYPE_INVALID:
1467                         break;
1468
1469                 case FORMAT_TYPE_NRCHARS: {
1470                         /* skip %n 's argument */
1471                         int qualifier = spec.qualifier;
1472                         void *skip_arg;
1473                         if (qualifier == 'l')
1474                                 skip_arg = va_arg(args, long *);
1475                         else if (qualifier == 'Z' || qualifier == 'z')
1476                                 skip_arg = va_arg(args, size_t *);
1477                         else
1478                                 skip_arg = va_arg(args, int *);
1479                         break;
1480                 }
1481
1482                 default:
1483                         switch (spec.type) {
1484
1485                         case FORMAT_TYPE_LONG_LONG:
1486                                 save_arg(long long);
1487                                 break;
1488                         case FORMAT_TYPE_ULONG:
1489                         case FORMAT_TYPE_LONG:
1490                                 save_arg(unsigned long);
1491                                 break;
1492                         case FORMAT_TYPE_SIZE_T:
1493                                 save_arg(size_t);
1494                                 break;
1495                         case FORMAT_TYPE_PTRDIFF:
1496                                 save_arg(ptrdiff_t);
1497                                 break;
1498                         case FORMAT_TYPE_UBYTE:
1499                         case FORMAT_TYPE_BYTE:
1500                                 save_arg(char);
1501                                 break;
1502                         case FORMAT_TYPE_USHORT:
1503                         case FORMAT_TYPE_SHORT:
1504                                 save_arg(short);
1505                                 break;
1506                         default:
1507                                 save_arg(int);
1508                         }
1509                 }
1510         }
1511         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1512
1513 #undef save_arg
1514 }
1515 EXPORT_SYMBOL_GPL(vbin_printf);
1516
1517 /**
1518  * bstr_printf - Format a string from binary arguments and place it in a buffer
1519  * @buf: The buffer to place the result into
1520  * @size: The size of the buffer, including the trailing null space
1521  * @fmt: The format string to use
1522  * @bin_buf: Binary arguments for the format string
1523  *
1524  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1525  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1526  * a binary buffer that generated by vbin_printf.
1527  *
1528  * The format follows C99 vsnprintf, but has some extensions:
1529  *  see vsnprintf comment for details.
1530  *
1531  * The return value is the number of characters which would
1532  * be generated for the given input, excluding the trailing
1533  * '\0', as per ISO C99. If you want to have the exact
1534  * number of characters written into @buf as return value
1535  * (not including the trailing '\0'), use vscnprintf(). If the
1536  * return is greater than or equal to @size, the resulting
1537  * string is truncated.
1538  */
1539 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1540 {
1541         unsigned long long num;
1542         char *str, *end, c;
1543         const char *args = (const char *)bin_buf;
1544
1545         struct printf_spec spec = {0};
1546
1547         if (WARN_ON_ONCE((int) size < 0))
1548                 return 0;
1549
1550         str = buf;
1551         end = buf + size;
1552
1553 #define get_arg(type)                                                   \
1554 ({                                                                      \
1555         typeof(type) value;                                             \
1556         if (sizeof(type) == 8) {                                        \
1557                 args = PTR_ALIGN(args, sizeof(u32));                    \
1558                 *(u32 *)&value = *(u32 *)args;                          \
1559                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
1560         } else {                                                        \
1561                 args = PTR_ALIGN(args, sizeof(type));                   \
1562                 value = *(typeof(type) *)args;                          \
1563         }                                                               \
1564         args += sizeof(type);                                           \
1565         value;                                                          \
1566 })
1567
1568         /* Make sure end is always >= buf */
1569         if (end < buf) {
1570                 end = ((void *)-1);
1571                 size = end - buf;
1572         }
1573
1574         while (*fmt) {
1575                 int read;
1576                 const char *old_fmt = fmt;
1577
1578                 read = format_decode(fmt, &spec);
1579
1580                 fmt += read;
1581
1582                 switch (spec.type) {
1583                 case FORMAT_TYPE_NONE: {
1584                         int copy = read;
1585                         if (str < end) {
1586                                 if (copy > end - str)
1587                                         copy = end - str;
1588                                 memcpy(str, old_fmt, copy);
1589                         }
1590                         str += read;
1591                         break;
1592                 }
1593
1594                 case FORMAT_TYPE_WIDTH:
1595                         spec.field_width = get_arg(int);
1596                         break;
1597
1598                 case FORMAT_TYPE_PRECISION:
1599                         spec.precision = get_arg(int);
1600                         break;
1601
1602                 case FORMAT_TYPE_CHAR:
1603                         if (!(spec.flags & LEFT)) {
1604                                 while (--spec.field_width > 0) {
1605                                         if (str < end)
1606                                                 *str = ' ';
1607                                         ++str;
1608                                 }
1609                         }
1610                         c = (unsigned char) get_arg(char);
1611                         if (str < end)
1612                                 *str = c;
1613                         ++str;
1614                         while (--spec.field_width > 0) {
1615                                 if (str < end)
1616                                         *str = ' ';
1617                                 ++str;
1618                         }
1619                         break;
1620
1621                 case FORMAT_TYPE_STR: {
1622                         const char *str_arg = args;
1623                         size_t len = strlen(str_arg);
1624                         args += len + 1;
1625                         str = string(str, end, (char *)str_arg, spec);
1626                         break;
1627                 }
1628
1629                 case FORMAT_TYPE_PTR:
1630                         str = pointer(fmt+1, str, end, get_arg(void *), spec);
1631                         while (isalnum(*fmt))
1632                                 fmt++;
1633                         break;
1634
1635                 case FORMAT_TYPE_PERCENT_CHAR:
1636                         if (str < end)
1637                                 *str = '%';
1638                         ++str;
1639                         break;
1640
1641                 case FORMAT_TYPE_INVALID:
1642                         if (str < end)
1643                                 *str = '%';
1644                         ++str;
1645                         break;
1646
1647                 case FORMAT_TYPE_NRCHARS:
1648                         /* skip */
1649                         break;
1650
1651                 default:
1652                         switch (spec.type) {
1653
1654                         case FORMAT_TYPE_LONG_LONG:
1655                                 num = get_arg(long long);
1656                                 break;
1657                         case FORMAT_TYPE_ULONG:
1658                                 num = get_arg(unsigned long);
1659                                 break;
1660                         case FORMAT_TYPE_LONG:
1661                                 num = get_arg(unsigned long);
1662                                 break;
1663                         case FORMAT_TYPE_SIZE_T:
1664                                 num = get_arg(size_t);
1665                                 break;
1666                         case FORMAT_TYPE_PTRDIFF:
1667                                 num = get_arg(ptrdiff_t);
1668                                 break;
1669                         case FORMAT_TYPE_UBYTE:
1670                                 num = get_arg(unsigned char);
1671                                 break;
1672                         case FORMAT_TYPE_BYTE:
1673                                 num = get_arg(signed char);
1674                                 break;
1675                         case FORMAT_TYPE_USHORT:
1676                                 num = get_arg(unsigned short);
1677                                 break;
1678                         case FORMAT_TYPE_SHORT:
1679                                 num = get_arg(short);
1680                                 break;
1681                         case FORMAT_TYPE_UINT:
1682                                 num = get_arg(unsigned int);
1683                                 break;
1684                         default:
1685                                 num = get_arg(int);
1686                         }
1687
1688                         str = number(str, end, num, spec);
1689                 }
1690         }
1691
1692         if (size > 0) {
1693                 if (str < end)
1694                         *str = '\0';
1695                 else
1696                         end[-1] = '\0';
1697         }
1698
1699 #undef get_arg
1700
1701         /* the trailing null byte doesn't count towards the total */
1702         return str - buf;
1703 }
1704 EXPORT_SYMBOL_GPL(bstr_printf);
1705
1706 /**
1707  * bprintf - Parse a format string and place args' binary value in a buffer
1708  * @bin_buf: The buffer to place args' binary value
1709  * @size: The size of the buffer(by words(32bits), not characters)
1710  * @fmt: The format string to use
1711  * @...: Arguments for the format string
1712  *
1713  * The function returns the number of words(u32) written
1714  * into @bin_buf.
1715  */
1716 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1717 {
1718         va_list args;
1719         int ret;
1720
1721         va_start(args, fmt);
1722         ret = vbin_printf(bin_buf, size, fmt, args);
1723         va_end(args);
1724         return ret;
1725 }
1726 EXPORT_SYMBOL_GPL(bprintf);
1727
1728 #endif /* CONFIG_BINARY_PRINTF */
1729
1730 /**
1731  * vsscanf - Unformat a buffer into a list of arguments
1732  * @buf:        input buffer
1733  * @fmt:        format of buffer
1734  * @args:       arguments
1735  */
1736 int vsscanf(const char * buf, const char * fmt, va_list args)
1737 {
1738         const char *str = buf;
1739         char *next;
1740         char digit;
1741         int num = 0;
1742         int qualifier;
1743         int base;
1744         int field_width;
1745         int is_sign = 0;
1746
1747         while(*fmt && *str) {
1748                 /* skip any white space in format */
1749                 /* white space in format matchs any amount of
1750                  * white space, including none, in the input.
1751                  */
1752                 if (isspace(*fmt)) {
1753                         while (isspace(*fmt))
1754                                 ++fmt;
1755                         while (isspace(*str))
1756                                 ++str;
1757                 }
1758
1759                 /* anything that is not a conversion must match exactly */
1760                 if (*fmt != '%' && *fmt) {
1761                         if (*fmt++ != *str++)
1762                                 break;
1763                         continue;
1764                 }
1765
1766                 if (!*fmt)
1767                         break;
1768                 ++fmt;
1769
1770                 /* skip this conversion.
1771                  * advance both strings to next white space
1772                  */
1773                 if (*fmt == '*') {
1774                         while (!isspace(*fmt) && *fmt != '%' && *fmt)
1775                                 fmt++;
1776                         while (!isspace(*str) && *str)
1777                                 str++;
1778                         continue;
1779                 }
1780
1781                 /* get field width */
1782                 field_width = -1;
1783                 if (isdigit(*fmt))
1784                         field_width = skip_atoi(&fmt);
1785
1786                 /* get conversion qualifier */
1787                 qualifier = -1;
1788                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
1789                     *fmt == 'Z' || *fmt == 'z') {
1790                         qualifier = *fmt++;
1791                         if (unlikely(qualifier == *fmt)) {
1792                                 if (qualifier == 'h') {
1793                                         qualifier = 'H';
1794                                         fmt++;
1795                                 } else if (qualifier == 'l') {
1796                                         qualifier = 'L';
1797                                         fmt++;
1798                                 }
1799                         }
1800                 }
1801                 base = 10;
1802                 is_sign = 0;
1803
1804                 if (!*fmt || !*str)
1805                         break;
1806
1807                 switch(*fmt++) {
1808                 case 'c':
1809                 {
1810                         char *s = (char *) va_arg(args,char*);
1811                         if (field_width == -1)
1812                                 field_width = 1;
1813                         do {
1814                                 *s++ = *str++;
1815                         } while (--field_width > 0 && *str);
1816                         num++;
1817                 }
1818                 continue;
1819                 case 's':
1820                 {
1821                         char *s = (char *) va_arg(args, char *);
1822                         if(field_width == -1)
1823                                 field_width = INT_MAX;
1824                         /* first, skip leading white space in buffer */
1825                         while (isspace(*str))
1826                                 str++;
1827
1828                         /* now copy until next white space */
1829                         while (*str && !isspace(*str) && field_width--) {
1830                                 *s++ = *str++;
1831                         }
1832                         *s = '\0';
1833                         num++;
1834                 }
1835                 continue;
1836                 case 'n':
1837                         /* return number of characters read so far */
1838                 {
1839                         int *i = (int *)va_arg(args,int*);
1840                         *i = str - buf;
1841                 }
1842                 continue;
1843                 case 'o':
1844                         base = 8;
1845                         break;
1846                 case 'x':
1847                 case 'X':
1848                         base = 16;
1849                         break;
1850                 case 'i':
1851                         base = 0;
1852                 case 'd':
1853                         is_sign = 1;
1854                 case 'u':
1855                         break;
1856                 case '%':
1857                         /* looking for '%' in str */
1858                         if (*str++ != '%')
1859                                 return num;
1860                         continue;
1861                 default:
1862                         /* invalid format; stop here */
1863                         return num;
1864                 }
1865
1866                 /* have some sort of integer conversion.
1867                  * first, skip white space in buffer.
1868                  */
1869                 while (isspace(*str))
1870                         str++;
1871
1872                 digit = *str;
1873                 if (is_sign && digit == '-')
1874                         digit = *(str + 1);
1875
1876                 if (!digit
1877                     || (base == 16 && !isxdigit(digit))
1878                     || (base == 10 && !isdigit(digit))
1879                     || (base == 8 && (!isdigit(digit) || digit > '7'))
1880                     || (base == 0 && !isdigit(digit)))
1881                                 break;
1882
1883                 switch(qualifier) {
1884                 case 'H':       /* that's 'hh' in format */
1885                         if (is_sign) {
1886                                 signed char *s = (signed char *) va_arg(args,signed char *);
1887                                 *s = (signed char) simple_strtol(str,&next,base);
1888                         } else {
1889                                 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
1890                                 *s = (unsigned char) simple_strtoul(str, &next, base);
1891                         }
1892                         break;
1893                 case 'h':
1894                         if (is_sign) {
1895                                 short *s = (short *) va_arg(args,short *);
1896                                 *s = (short) simple_strtol(str,&next,base);
1897                         } else {
1898                                 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
1899                                 *s = (unsigned short) simple_strtoul(str, &next, base);
1900                         }
1901                         break;
1902                 case 'l':
1903                         if (is_sign) {
1904                                 long *l = (long *) va_arg(args,long *);
1905                                 *l = simple_strtol(str,&next,base);
1906                         } else {
1907                                 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
1908                                 *l = simple_strtoul(str,&next,base);
1909                         }
1910                         break;
1911                 case 'L':
1912                         if (is_sign) {
1913                                 long long *l = (long long*) va_arg(args,long long *);
1914                                 *l = simple_strtoll(str,&next,base);
1915                         } else {
1916                                 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
1917                                 *l = simple_strtoull(str,&next,base);
1918                         }
1919                         break;
1920                 case 'Z':
1921                 case 'z':
1922                 {
1923                         size_t *s = (size_t*) va_arg(args,size_t*);
1924                         *s = (size_t) simple_strtoul(str,&next,base);
1925                 }
1926                 break;
1927                 default:
1928                         if (is_sign) {
1929                                 int *i = (int *) va_arg(args, int*);
1930                                 *i = (int) simple_strtol(str,&next,base);
1931                         } else {
1932                                 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
1933                                 *i = (unsigned int) simple_strtoul(str,&next,base);
1934                         }
1935                         break;
1936                 }
1937                 num++;
1938
1939                 if (!next)
1940                         break;
1941                 str = next;
1942         }
1943
1944         /*
1945          * Now we've come all the way through so either the input string or the
1946          * format ended. In the former case, there can be a %n at the current
1947          * position in the format that needs to be filled.
1948          */
1949         if (*fmt == '%' && *(fmt + 1) == 'n') {
1950                 int *p = (int *)va_arg(args, int *);
1951                 *p = str - buf;
1952         }
1953
1954         return num;
1955 }
1956 EXPORT_SYMBOL(vsscanf);
1957
1958 /**
1959  * sscanf - Unformat a buffer into a list of arguments
1960  * @buf:        input buffer
1961  * @fmt:        formatting of buffer
1962  * @...:        resulting arguments
1963  */
1964 int sscanf(const char * buf, const char * fmt, ...)
1965 {
1966         va_list args;
1967         int i;
1968
1969         va_start(args,fmt);
1970         i = vsscanf(buf,fmt,args);
1971         va_end(args);
1972         return i;
1973 }
1974 EXPORT_SYMBOL(sscanf);