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
  29 #include <asm/page.h>           /* for PAGE_SIZE */
  30 #include <asm/div64.h>
  31 #include <asm/sections.h>       /* for dereference_function_descriptor() */
  32
  33 /* Works only for digits and letters, but small and fast */
  34 #define TOLOWER(x) ((x) | 0x20)
  35
  36 static unsigned int simple_guess_base(const char *cp)
  37 {
  38         if (cp[0] == '0') {
  39                 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
  40                         return 16;
  41                 else
  42                         return 8;
  43         } else {
  44                 return 10;
  45         }
  46 }
  47
  48 /**
  49  * simple_strtoul - convert a string to an unsigned long
  50  * @cp: The start of the string
  51  * @endp: A pointer to the end of the parsed string will be placed here
  52  * @base: The number base to use
  53  */
  54 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  55 {
  56         unsigned long result = 0;
  57
  58         if (!base)
  59                 base = simple_guess_base(cp);
  60
  61         if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
  62                 cp += 2;
  63
  64         while (isxdigit(*cp)) {
  65                 unsigned int value;
  66
  67                 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
  68                 if (value >= base)
  69                         break;
  70                 result = result * base + value;
  71                 cp++;
  72         }
  73
  74         if (endp)
  75                 *endp = (char *)cp;
  76         return result;
  77 }
  78 EXPORT_SYMBOL(simple_strtoul);
  79
  80 /**
  81  * simple_strtol - convert a string to a signed long
  82  * @cp: The start of the string
  83  * @endp: A pointer to the end of the parsed string will be placed here
  84  * @base: The number base to use
  85  */
  86 long simple_strtol(const char *cp, char **endp, unsigned int base)
  87 {
  88         if(*cp == '-')
  89                 return -simple_strtoul(cp + 1, endp, base);
  90         return simple_strtoul(cp, endp, base);
  91 }
  92 EXPORT_SYMBOL(simple_strtol);
  93
  94 /**
  95  * simple_strtoull - convert a string to an unsigned long long
  96  * @cp: The start of the string
  97  * @endp: A pointer to the end of the parsed string will be placed here
  98  * @base: The number base to use
  99  */
 100 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
 101 {
 102         unsigned long long result = 0;
 103
 104         if (!base)
 105                 base = simple_guess_base(cp);
 106
 107         if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
 108                 cp += 2;
 109
 110         while (isxdigit(*cp)) {
 111                 unsigned int value;
 112
 113                 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
 114                 if (value >= base)
 115                         break;
 116                 result = result * base + value;
 117                 cp++;
 118         }
 119
 120         if (endp)
 121                 *endp = (char *)cp;
 122         return result;
 123 }
 124 EXPORT_SYMBOL(simple_strtoull);
 125
 126 /**
 127  * simple_strtoll - convert a string to a signed long long
 128  * @cp: The start of the string
 129  * @endp: A pointer to the end of the parsed string will be placed here
 130  * @base: The number base to use
 131  */
 132 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 133 {
 134         if(*cp=='-')
 135                 return -simple_strtoull(cp + 1, endp, base);
 136         return simple_strtoull(cp, endp, base);
 137 }
 138
 139 /**
 140  * strict_strtoul - convert a string to an unsigned long strictly
 141  * @cp: The string to be converted
 142  * @base: The number base to use
 143  * @res: The converted result value
 144  *
 145  * strict_strtoul converts a string to an unsigned long only if the
 146  * string is really an unsigned long string, any string containing
 147  * any invalid char at the tail will be rejected and -EINVAL is returned,
 148  * only a newline char at the tail is acceptible because people generally
 149  * change a module parameter in the following way:
 150  *
 151  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 152  *
 153  * echo will append a newline to the tail.
 154  *
 155  * It returns 0 if conversion is successful and *res is set to the converted
 156  * value, otherwise it returns -EINVAL and *res is set to 0.
 157  *
 158  * simple_strtoul just ignores the successive invalid characters and
 159  * return the converted value of prefix part of the string.
 160  */
 161 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
 162 {
 163         char *tail;
 164         unsigned long val;
 165         size_t len;
 166
 167         *res = 0;
 168         len = strlen(cp);
 169         if (len == 0)
 170                 return -EINVAL;
 171
 172         val = simple_strtoul(cp, &tail, base);
 173         if (tail == cp)
 174                 return -EINVAL;
 175         if ((*tail == '\0') ||
 176                 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 177                 *res = val;
 178                 return 0;
 179         }
 180
 181         return -EINVAL;
 182 }
 183 EXPORT_SYMBOL(strict_strtoul);
 184
 185 /**
 186  * strict_strtol - convert a string to a long strictly
 187  * @cp: The string to be converted
 188  * @base: The number base to use
 189  * @res: The converted result value
 190  *
 191  * strict_strtol is similiar to strict_strtoul, but it allows the first
 192  * character of a string is '-'.
 193  *
 194  * It returns 0 if conversion is successful and *res is set to the converted
 195  * value, otherwise it returns -EINVAL and *res is set to 0.
 196  */
 197 int strict_strtol(const char *cp, unsigned int base, long *res)
 198 {
 199         int ret;
 200         if (*cp == '-') {
 201                 ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
 202                 if (!ret)
 203                         *res = -(*res);
 204         } else {
 205                 ret = strict_strtoul(cp, base, (unsigned long *)res);
 206         }
 207
 208         return ret;
 209 }
 210 EXPORT_SYMBOL(strict_strtol);
 211
 212 /**
 213  * strict_strtoull - convert a string to an unsigned long long strictly
 214  * @cp: The string to be converted
 215  * @base: The number base to use
 216  * @res: The converted result value
 217  *
 218  * strict_strtoull converts a string to an unsigned long long only if the
 219  * string is really an unsigned long long string, any string containing
 220  * any invalid char at the tail will be rejected and -EINVAL is returned,
 221  * only a newline char at the tail is acceptible because people generally
 222  * change a module parameter in the following way:
 223  *
 224  *      echo 1024 > /sys/module/e1000/parameters/copybreak
 225  *
 226  * echo will append a newline to the tail of the string.
 227  *
 228  * It returns 0 if conversion is successful and *res is set to the converted
 229  * value, otherwise it returns -EINVAL and *res is set to 0.
 230  *
 231  * simple_strtoull just ignores the successive invalid characters and
 232  * return the converted value of prefix part of the string.
 233  */
 234 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
 235 {
 236         char *tail;
 237         unsigned long long val;
 238         size_t len;
 239
 240         *res = 0;
 241         len = strlen(cp);
 242         if (len == 0)
 243                 return -EINVAL;
 244
 245         val = simple_strtoull(cp, &tail, base);
 246         if (tail == cp)
 247                 return -EINVAL;
 248         if ((*tail == '\0') ||
 249                 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 250                 *res = val;
 251                 return 0;
 252         }
 253
 254         return -EINVAL;
 255 }
 256 EXPORT_SYMBOL(strict_strtoull);
 257
 258 /**
 259  * strict_strtoll - convert a string to a long long strictly
 260  * @cp: The string to be converted
 261  * @base: The number base to use
 262  * @res: The converted result value
 263  *
 264  * strict_strtoll is similiar to strict_strtoull, but it allows the first
 265  * character of a string is '-'.
 266  *
 267  * It returns 0 if conversion is successful and *res is set to the converted
 268  * value, otherwise it returns -EINVAL and *res is set to 0.
 269  */
 270 int strict_strtoll(const char *cp, unsigned int base, long long *res)
 271 {
 272         int ret;
 273         if (*cp == '-') {
 274                 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
 275                 if (!ret)
 276                         *res = -(*res);
 277         } else {
 278                 ret = strict_strtoull(cp, base, (unsigned long long *)res);
 279         }
 280
 281         return ret;
 282 }
 283 EXPORT_SYMBOL(strict_strtoll);
 284
 285 static int skip_atoi(const char **s)
 286 {
 287         int i=0;
 288
 289         while (isdigit(**s))
 290                 i = i*10 + *((*s)++) - '0';
 291         return i;
 292 }
 293
 294 /* Decimal conversion is by far the most typical, and is used
 295  * for /proc and /sys data. This directly impacts e.g. top performance
 296  * with many processes running. We optimize it for speed
 297  * using code from
 298  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 299  * (with permission from the author, Douglas W. Jones). */
 300
 301 /* Formats correctly any integer in [0,99999].
 302  * Outputs from one to five digits depending on input.
 303  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
 304 static char* put_dec_trunc(char *buf, unsigned q)
 305 {
 306         unsigned d3, d2, d1, d0;
 307         d1 = (q>>4) & 0xf;
 308         d2 = (q>>8) & 0xf;
 309         d3 = (q>>12);
 310
 311         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 312         q = (d0 * 0xcd) >> 11;
 313         d0 = d0 - 10*q;
 314         *buf++ = d0 + '0'; /* least significant digit */
 315         d1 = q + 9*d3 + 5*d2 + d1;
 316         if (d1 != 0) {
 317                 q = (d1 * 0xcd) >> 11;
 318                 d1 = d1 - 10*q;
 319                 *buf++ = d1 + '0'; /* next digit */
 320
 321                 d2 = q + 2*d2;
 322                 if ((d2 != 0) || (d3 != 0)) {
 323                         q = (d2 * 0xd) >> 7;
 324                         d2 = d2 - 10*q;
 325                         *buf++ = d2 + '0'; /* next digit */
 326
 327                         d3 = q + 4*d3;
 328                         if (d3 != 0) {
 329                                 q = (d3 * 0xcd) >> 11;
 330                                 d3 = d3 - 10*q;
 331                                 *buf++ = d3 + '0';  /* next digit */
 332                                 if (q != 0)
 333                                         *buf++ = q + '0';  /* most sign. digit */
 334                         }
 335                 }
 336         }
 337         return buf;
 338 }
 339 /* Same with if's removed. Always emits five digits */
 340 static char* put_dec_full(char *buf, unsigned q)
 341 {
 342         /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
 343         /* but anyway, gcc produces better code with full-sized ints */
 344         unsigned d3, d2, d1, d0;
 345         d1 = (q>>4) & 0xf;
 346         d2 = (q>>8) & 0xf;
 347         d3 = (q>>12);
 348
 349         /* Possible ways to approx. divide by 10 */
 350         /* gcc -O2 replaces multiply with shifts and adds */
 351         // (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
 352         // (x * 0x67) >> 10:  1100111
 353         // (x * 0x34) >> 9:    110100 - same
 354         // (x * 0x1a) >> 8:     11010 - same
 355         // (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
 356
 357         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 358         q = (d0 * 0xcd) >> 11;
 359         d0 = d0 - 10*q;
 360         *buf++ = d0 + '0';
 361         d1 = q + 9*d3 + 5*d2 + d1;
 362                 q = (d1 * 0xcd) >> 11;
 363                 d1 = d1 - 10*q;
 364                 *buf++ = d1 + '0';
 365
 366                 d2 = q + 2*d2;
 367                         q = (d2 * 0xd) >> 7;
 368                         d2 = d2 - 10*q;
 369                         *buf++ = d2 + '0';
 370
 371                         d3 = q + 4*d3;
 372                                 q = (d3 * 0xcd) >> 11; /* - shorter code */
 373                                 /* q = (d3 * 0x67) >> 10; - would also work */
 374                                 d3 = d3 - 10*q;
 375                                 *buf++ = d3 + '0';
 376                                         *buf++ = q + '0';
 377         return buf;
 378 }
 379 /* No inlining helps gcc to use registers better */
 380 static noinline char* put_dec(char *buf, unsigned long long num)
 381 {
 382         while (1) {
 383                 unsigned rem;
 384                 if (num < 100000)
 385                         return put_dec_trunc(buf, num);
 386                 rem = do_div(num, 100000);
 387                 buf = put_dec_full(buf, rem);
 388         }
 389 }
 390
 391 #define ZEROPAD 1               /* pad with zero */
 392 #define SIGN    2               /* unsigned/signed long */
 393 #define PLUS    4               /* show plus */
 394 #define SPACE   8               /* space if plus */
 395 #define LEFT    16              /* left justified */
 396 #define SMALL   32              /* Must be 32 == 0x20 */
 397 #define SPECIAL 64              /* 0x */
 398
 399 enum format_type {
 400         FORMAT_TYPE_NONE, /* Just a string part */
 401         FORMAT_TYPE_WITDH,
 402         FORMAT_TYPE_PRECISION,
 403         FORMAT_TYPE_CHAR,
 404         FORMAT_TYPE_STR,
 405         FORMAT_TYPE_PTR,
 406         FORMAT_TYPE_PERCENT_CHAR,
 407         FORMAT_TYPE_INVALID,
 408         FORMAT_TYPE_LONG_LONG,
 409         FORMAT_TYPE_ULONG,
 410         FORMAT_TYPE_LONG,
 411         FORMAT_TYPE_USHORT,
 412         FORMAT_TYPE_SHORT,
 413         FORMAT_TYPE_UINT,
 414         FORMAT_TYPE_INT,
 415         FORMAT_TYPE_NRCHARS,
 416         FORMAT_TYPE_SIZE_T,
 417         FORMAT_TYPE_PTRDIFF
 418 };
 419
 420 struct printf_spec {
 421         enum format_type        type;
 422         int                     flags;          /* flags to number() */
 423         int                     field_width;    /* width of output field */
 424         int                     base;
 425         int                     precision;      /* # of digits/chars */
 426         int                     qualifier;
 427 };
 428
 429 static char *number(char *buf, char *end, unsigned long long num,
 430                         struct printf_spec spec)
 431 {
 432         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 433         static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 434
 435         char tmp[66];
 436         char sign;
 437         char locase;
 438         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 439         int i;
 440
 441         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 442          * produces same digits or (maybe lowercased) letters */
 443         locase = (spec.flags & SMALL);
 444         if (spec.flags & LEFT)
 445                 spec.flags &= ~ZEROPAD;
 446         sign = 0;
 447         if (spec.flags & SIGN) {
 448                 if ((signed long long) num < 0) {
 449                         sign = '-';
 450                         num = - (signed long long) num;
 451                         spec.field_width--;
 452                 } else if (spec.flags & PLUS) {
 453                         sign = '+';
 454                         spec.field_width--;
 455                 } else if (spec.flags & SPACE) {
 456                         sign = ' ';
 457                         spec.field_width--;
 458                 }
 459         }
 460         if (need_pfx) {
 461                 spec.field_width--;
 462                 if (spec.base == 16)
 463                         spec.field_width--;
 464         }
 465
 466         /* generate full string in tmp[], in reverse order */
 467         i = 0;
 468         if (num == 0)
 469                 tmp[i++] = '0';
 470         /* Generic code, for any base:
 471         else do {
 472                 tmp[i++] = (digits[do_div(num,base)] | locase);
 473         } while (num != 0);
 474         */
 475         else if (spec.base != 10) { /* 8 or 16 */
 476                 int mask = spec.base - 1;
 477                 int shift = 3;
 478                 if (spec.base == 16) shift = 4;
 479                 do {
 480                         tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 481                         num >>= shift;
 482                 } while (num);
 483         } else { /* base 10 */
 484                 i = put_dec(tmp, num) - tmp;
 485         }
 486
 487         /* printing 100 using %2d gives "100", not "00" */
 488         if (i > spec.precision)
 489                 spec.precision = i;
 490         /* leading space padding */
 491         spec.field_width -= spec.precision;
 492         if (!(spec.flags & (ZEROPAD+LEFT))) {
 493                 while(--spec.field_width >= 0) {
 494                         if (buf < end)
 495                                 *buf = ' ';
 496                         ++buf;
 497                 }
 498         }
 499         /* sign */
 500         if (sign) {
 501                 if (buf < end)
 502                         *buf = sign;
 503                 ++buf;
 504         }
 505         /* "0x" / "0" prefix */
 506         if (need_pfx) {
 507                 if (buf < end)
 508                         *buf = '0';
 509                 ++buf;
 510                 if (spec.base == 16) {
 511                         if (buf < end)
 512                                 *buf = ('X' | locase);
 513                         ++buf;
 514                 }
 515         }
 516         /* zero or space padding */
 517         if (!(spec.flags & LEFT)) {
 518                 char c = (spec.flags & ZEROPAD) ? '0' : ' ';
 519                 while (--spec.field_width >= 0) {
 520                         if (buf < end)
 521                                 *buf = c;
 522                         ++buf;
 523                 }
 524         }
 525         /* hmm even more zero padding? */
 526         while (i <= --spec.precision) {
 527                 if (buf < end)
 528                         *buf = '0';
 529                 ++buf;
 530         }
 531         /* actual digits of result */
 532         while (--i >= 0) {
 533                 if (buf < end)
 534                         *buf = tmp[i];
 535                 ++buf;
 536         }
 537         /* trailing space padding */
 538         while (--spec.field_width >= 0) {
 539                 if (buf < end)
 540                         *buf = ' ';
 541                 ++buf;
 542         }
 543         return buf;
 544 }
 545
 546 static char *string(char *buf, char *end, char *s, struct printf_spec spec)
 547 {
 548         int len, i;
 549
 550         if ((unsigned long)s < PAGE_SIZE)
 551                 s = "<NULL>";
 552
 553         len = strnlen(s, spec.precision);
 554
 555         if (!(spec.flags & LEFT)) {
 556                 while (len < spec.field_width--) {
 557                         if (buf < end)
 558                                 *buf = ' ';
 559                         ++buf;
 560                 }
 561         }
 562         for (i = 0; i < len; ++i) {
 563                 if (buf < end)
 564                         *buf = *s;
 565                 ++buf; ++s;
 566         }
 567         while (len < spec.field_width--) {
 568                 if (buf < end)
 569                         *buf = ' ';
 570                 ++buf;
 571         }
 572         return buf;
 573 }
 574
 575 static char *symbol_string(char *buf, char *end, void *ptr,
 576                                 struct printf_spec spec)
 577 {
 578         unsigned long value = (unsigned long) ptr;
 579 #ifdef CONFIG_KALLSYMS
 580         char sym[KSYM_SYMBOL_LEN];
 581         sprint_symbol(sym, value);
 582         return string(buf, end, sym, spec);
 583 #else
 584         spec.field_width = 2*sizeof(void *);
 585         spec.flags |= SPECIAL | SMALL | ZEROPAD;
 586         spec.base = 16;
 587         return number(buf, end, value, spec);
 588 #endif
 589 }
 590
 591 static char *resource_string(char *buf, char *end, struct resource *res,
 592                                 struct printf_spec spec)
 593 {
 594 #ifndef IO_RSRC_PRINTK_SIZE
 595 #define IO_RSRC_PRINTK_SIZE     4
 596 #endif
 597
 598 #ifndef MEM_RSRC_PRINTK_SIZE
 599 #define MEM_RSRC_PRINTK_SIZE    8
 600 #endif
 601         struct printf_spec num_spec = {
 602                 .base = 16,
 603                 .precision = -1,
 604                 .flags = SPECIAL | SMALL | ZEROPAD,
 605         };
 606         /* room for the actual numbers, the two "0x", -, [, ] and the final zero */
 607         char sym[4*sizeof(resource_size_t) + 8];
 608         char *p = sym, *pend = sym + sizeof(sym);
 609         int size = -1;
 610
 611         if (res->flags & IORESOURCE_IO)
 612                 size = IO_RSRC_PRINTK_SIZE;
 613         else if (res->flags & IORESOURCE_MEM)
 614                 size = MEM_RSRC_PRINTK_SIZE;
 615
 616         *p++ = '[';
 617         num_spec.field_width = size;
 618         p = number(p, pend, res->start, num_spec);
 619         *p++ = '-';
 620         p = number(p, pend, res->end, num_spec);
 621         *p++ = ']';
 622         *p = 0;
 623
 624         return string(buf, end, sym, spec);
 625 }
 626
 627 static char *mac_address_string(char *buf, char *end, u8 *addr,
 628                                 struct printf_spec spec)
 629 {
 630         char mac_addr[6 * 3]; /* (6 * 2 hex digits), 5 colons and trailing zero */
 631         char *p = mac_addr;
 632         int i;
 633
 634         for (i = 0; i < 6; i++) {
 635                 p = pack_hex_byte(p, addr[i]);
 636                 if (!(spec.flags & SPECIAL) && i != 5)
 637                         *p++ = ':';
 638         }
 639         *p = '\0';
 640         spec.flags &= ~SPECIAL;
 641
 642         return string(buf, end, mac_addr, spec);
 643 }
 644
 645 static char *ip6_addr_string(char *buf, char *end, u8 *addr,
 646                                 struct printf_spec spec)
 647 {
 648         char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */
 649         char *p = ip6_addr;
 650         int i;
 651
 652         for (i = 0; i < 8; i++) {
 653                 p = pack_hex_byte(p, addr[2 * i]);
 654                 p = pack_hex_byte(p, addr[2 * i + 1]);
 655                 if (!(spec.flags & SPECIAL) && i != 7)
 656                         *p++ = ':';
 657         }
 658         *p = '\0';
 659         spec.flags &= ~SPECIAL;
 660
 661         return string(buf, end, ip6_addr, spec);
 662 }
 663
 664 static char *ip4_addr_string(char *buf, char *end, u8 *addr,
 665                                 struct printf_spec spec)
 666 {
 667         char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */
 668         char temp[3];   /* hold each IP quad in reverse order */
 669         char *p = ip4_addr;
 670         int i, digits;
 671
 672         for (i = 0; i < 4; i++) {
 673                 digits = put_dec_trunc(temp, addr[i]) - temp;
 674                 /* reverse the digits in the quad */
 675                 while (digits--)
 676                         *p++ = temp[digits];
 677                 if (i != 3)
 678                         *p++ = '.';
 679         }
 680         *p = '\0';
 681         spec.flags &= ~SPECIAL;
 682
 683         return string(buf, end, ip4_addr, spec);
 684 }
 685
 686 /*
 687  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 688  * by an extra set of alphanumeric characters that are extended format
 689  * specifiers.
 690  *
 691  * Right now we handle:
 692  *
 693  * - 'F' For symbolic function descriptor pointers
 694  * - 'S' For symbolic direct pointers
 695  * - 'R' For a struct resource pointer, it prints the range of
 696  *       addresses (not the name nor the flags)
 697  * - 'M' For a 6-byte MAC address, it prints the address in the
 698  *       usual colon-separated hex notation
 699  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated
 700  *       decimal for v4 and colon separated network-order 16 bit hex for v6)
 701  * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
 702  *       currently the same
 703  *
 704  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 705  * function pointers are really function descriptors, which contain a
 706  * pointer to the real address.
 707  */
 708 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 709                         struct printf_spec spec)
 710 {
 711         if (!ptr)
 712                 return string(buf, end, "(null)", spec);
 713
 714         switch (*fmt) {
 715         case 'F':
 716                 ptr = dereference_function_descriptor(ptr);
 717                 /* Fallthrough */
 718         case 'S':
 719                 return symbol_string(buf, end, ptr, spec);
 720         case 'R':
 721                 return resource_string(buf, end, ptr, spec);
 722         case 'm':
 723                 spec.flags |= SPECIAL;
 724                 /* Fallthrough */
 725         case 'M':
 726                 return mac_address_string(buf, end, ptr, spec);
 727         case 'i':
 728                 spec.flags |= SPECIAL;
 729                 /* Fallthrough */
 730         case 'I':
 731                 if (fmt[1] == '6')
 732                         return ip6_addr_string(buf, end, ptr, spec);
 733                 if (fmt[1] == '4')
 734                         return ip4_addr_string(buf, end, ptr, spec);
 735                 spec.flags &= ~SPECIAL;
 736                 break;
 737         }
 738         spec.flags |= SMALL;
 739         if (spec.field_width == -1) {
 740                 spec.field_width = 2*sizeof(void *);
 741                 spec.flags |= ZEROPAD;
 742         }
 743         spec.base = 16;
 744
 745         return number(buf, end, (unsigned long) ptr, spec);
 746 }
 747
 748 /*
 749  * Helper function to decode printf style format.
 750  * Each call decode a token from the format and return the
 751  * number of characters read (or likely the delta where it wants
 752  * to go on the next call).
 753  * The decoded token is returned through the parameters
 754  *
 755  * 'h', 'l', or 'L' for integer fields
 756  * 'z' support added 23/7/1999 S.H.
 757  * 'z' changed to 'Z' --davidm 1/25/99
 758  * 't' added for ptrdiff_t
 759  *
 760  * @fmt: the format string
 761  * @type of the token returned
 762  * @flags: various flags such as +, -, # tokens..
 763  * @field_width: overwritten width
 764  * @base: base of the number (octal, hex, ...)
 765  * @precision: precision of a number
 766  * @qualifier: qualifier of a number (long, size_t, ...)
 767  */
 768 static int format_decode(const char *fmt, struct printf_spec *spec)
 769 {
 770         const char *start = fmt;
 771         bool sign = false;
 772
 773         /* we finished early by reading the field width */
 774         if (spec->type == FORMAT_TYPE_WITDH) {
 775                 if (spec->field_width < 0) {
 776                         spec->field_width = -spec->field_width;
 777                         spec->flags |= LEFT;
 778                 }
 779                 spec->type = FORMAT_TYPE_NONE;
 780                 goto precision;
 781         }
 782
 783         /* we finished early by reading the precision */
 784         if (spec->type == FORMAT_TYPE_PRECISION) {
 785                 if (spec->precision < 0)
 786                         spec->precision = 0;
 787
 788                 spec->type = FORMAT_TYPE_NONE;
 789                 goto qualifier;
 790         }
 791
 792         /* By default */
 793         spec->type = FORMAT_TYPE_NONE;
 794
 795         for (; *fmt ; ++fmt) {
 796                 if (*fmt == '%')
 797                         break;
 798         }
 799
 800         /* Return the current non-format string */
 801         if (fmt != start || !*fmt)
 802                 return fmt - start;
 803
 804         /* Process flags */
 805         spec->flags = 0;
 806
 807         while (1) { /* this also skips first '%' */
 808                 bool found = true;
 809
 810                 ++fmt;
 811
 812                 switch (*fmt) {
 813                 case '-': spec->flags |= LEFT;    break;
 814                 case '+': spec->flags |= PLUS;    break;
 815                 case ' ': spec->flags |= SPACE;   break;
 816                 case '#': spec->flags |= SPECIAL; break;
 817                 case '0': spec->flags |= ZEROPAD; break;
 818                 default:  found = false;
 819                 }
 820
 821                 if (!found)
 822                         break;
 823         }
 824
 825         /* get field width */
 826         spec->field_width = -1;
 827
 828         if (isdigit(*fmt))
 829                 spec->field_width = skip_atoi(&fmt);
 830         else if (*fmt == '*') {
 831                 /* it's the next argument */
 832                 spec->type = FORMAT_TYPE_WITDH;
 833                 return ++fmt - start;
 834         }
 835
 836 precision:
 837         /* get the precision */
 838         spec->precision = -1;
 839         if (*fmt == '.') {
 840                 ++fmt;
 841                 if (isdigit(*fmt)) {
 842                         spec->precision = skip_atoi(&fmt);
 843                         if (spec->precision < 0)
 844                                 spec->precision = 0;
 845                 } else if (*fmt == '*') {
 846                         /* it's the next argument */
 847                         spec->type = FORMAT_TYPE_WITDH;
 848                         return ++fmt - start;
 849                 }
 850         }
 851
 852 qualifier:
 853         /* get the conversion qualifier */
 854         spec->qualifier = -1;
 855         if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 856             *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
 857                 spec->qualifier = *fmt;
 858                 ++fmt;
 859                 if (spec->qualifier == 'l' && *fmt == 'l') {
 860                         spec->qualifier = 'L';
 861                         ++fmt;
 862                 }
 863         }
 864
 865         /* default base */
 866         spec->base = 10;
 867         switch (*fmt) {
 868         case 'c':
 869                 spec->type = FORMAT_TYPE_CHAR;
 870                 return ++fmt - start;
 871
 872         case 's':
 873                 spec->type = FORMAT_TYPE_STR;
 874                 return ++fmt - start;
 875
 876         case 'p':
 877                 spec->type = FORMAT_TYPE_PTR;
 878                 return fmt - start;
 879                 /* skip alnum */
 880
 881         case 'n':
 882                 spec->type = FORMAT_TYPE_NRCHARS;
 883                 return ++fmt - start;
 884
 885         case '%':
 886                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
 887                 return ++fmt - start;
 888
 889         /* integer number formats - set up the flags and "break" */
 890         case 'o':
 891                 spec->base = 8;
 892                 break;
 893
 894         case 'x':
 895                 spec->flags |= SMALL;
 896
 897         case 'X':
 898                 spec->base = 16;
 899                 break;
 900
 901         case 'd':
 902         case 'i':
 903                 sign = true;
 904         case 'u':
 905                 break;
 906
 907         default:
 908                 spec->type = FORMAT_TYPE_INVALID;
 909                 return fmt - start;
 910         }
 911
 912         if (spec->qualifier == 'L')
 913                 spec->type = FORMAT_TYPE_LONG_LONG;
 914         else if (spec->qualifier == 'l') {
 915                 if (sign)
 916                         spec->type = FORMAT_TYPE_LONG;
 917                 else
 918                         spec->type = FORMAT_TYPE_ULONG;
 919         } else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
 920                 spec->type = FORMAT_TYPE_SIZE_T;
 921         } else if (spec->qualifier == 't') {
 922                 spec->type = FORMAT_TYPE_PTRDIFF;
 923         } else if (spec->qualifier == 'h') {
 924                 if (sign)
 925                         spec->type = FORMAT_TYPE_SHORT;
 926                 else
 927                         spec->type = FORMAT_TYPE_USHORT;
 928         } else {
 929                 if (sign)
 930                         spec->type = FORMAT_TYPE_INT;
 931                 else
 932                         spec->type = FORMAT_TYPE_UINT;
 933         }
 934
 935         return ++fmt - start;
 936 }
 937
 938 /**
 939  * vsnprintf - Format a string and place it in a buffer
 940  * @buf: The buffer to place the result into
 941  * @size: The size of the buffer, including the trailing null space
 942  * @fmt: The format string to use
 943  * @args: Arguments for the format string
 944  *
 945  * This function follows C99 vsnprintf, but has some extensions:
 946  * %pS output the name of a text symbol
 947  * %pF output the name of a function pointer
 948  * %pR output the address range in a struct resource
 949  *
 950  * The return value is the number of characters which would
 951  * be generated for the given input, excluding the trailing
 952  * '\0', as per ISO C99. If you want to have the exact
 953  * number of characters written into @buf as return value
 954  * (not including the trailing '\0'), use vscnprintf(). If the
 955  * return is greater than or equal to @size, the resulting
 956  * string is truncated.
 957  *
 958  * Call this function if you are already dealing with a va_list.
 959  * You probably want snprintf() instead.
 960  */
 961 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 962 {
 963         unsigned long long num;
 964         char *str, *end, c;
 965         int read;
 966         struct printf_spec spec = {0};
 967
 968         /* Reject out-of-range values early.  Large positive sizes are
 969            used for unknown buffer sizes. */
 970         if (unlikely((int) size < 0)) {
 971                 /* There can be only one.. */
 972                 static char warn = 1;
 973                 WARN_ON(warn);
 974                 warn = 0;
 975                 return 0;
 976         }
 977
 978         str = buf;
 979         end = buf + size;
 980
 981         /* Make sure end is always >= buf */
 982         if (end < buf) {
 983                 end = ((void *)-1);
 984                 size = end - buf;
 985         }
 986
 987         while (*fmt) {
 988                 const char *old_fmt = fmt;
 989
 990                 read = format_decode(fmt, &spec);
 991
 992                 fmt += read;
 993
 994                 switch (spec.type) {
 995                 case FORMAT_TYPE_NONE: {
 996                         int copy = read;
 997                         if (str < end) {
 998                                 if (copy > end - str)
 999                                         copy = end - str;
1000                                 memcpy(str, old_fmt, copy);
1001                         }
1002                         str += read;
1003                         break;
1004                 }
1005
1006                 case FORMAT_TYPE_WITDH:
1007                         spec.field_width = va_arg(args, int);
1008                         break;
1009
1010                 case FORMAT_TYPE_PRECISION:
1011                         spec.precision = va_arg(args, int);
1012                         break;
1013
1014                 case FORMAT_TYPE_CHAR:
1015                         if (!(spec.flags & LEFT)) {
1016                                 while (--spec.field_width > 0) {
1017                                         if (str < end)
1018                                                 *str = ' ';
1019                                         ++str;
1020
1021                                 }
1022                         }
1023                         c = (unsigned char) va_arg(args, int);
1024                         if (str < end)
1025                                 *str = c;
1026                         ++str;
1027                         while (--spec.field_width > 0) {
1028                                 if (str < end)
1029                                         *str = ' ';
1030                                 ++str;
1031                         }
1032                         break;
1033
1034                 case FORMAT_TYPE_STR:
1035                         str = string(str, end, va_arg(args, char *), spec);
1036                         break;
1037
1038                 case FORMAT_TYPE_PTR:
1039                         str = pointer(fmt+1, str, end, va_arg(args, void *),
1040                                       spec);
1041                         while (isalnum(*fmt))
1042                                 fmt++;
1043                         break;
1044
1045                 case FORMAT_TYPE_PERCENT_CHAR:
1046                         if (str < end)
1047                                 *str = '%';
1048                         ++str;
1049                         break;
1050
1051                 case FORMAT_TYPE_INVALID:
1052                         if (str < end)
1053                                 *str = '%';
1054                         ++str;
1055                         if (*fmt) {
1056                                 if (str < end)
1057                                         *str = *fmt;
1058                                 ++str;
1059                         } else {
1060                                 --fmt;
1061                         }
1062                         break;
1063
1064                 case FORMAT_TYPE_NRCHARS: {
1065                         int qualifier = spec.qualifier;
1066
1067                         if (qualifier == 'l') {
1068                                 long *ip = va_arg(args, long *);
1069                                 *ip = (str - buf);
1070                         } else if (qualifier == 'Z' ||
1071                                         qualifier == 'z') {
1072                                 size_t *ip = va_arg(args, size_t *);
1073                                 *ip = (str - buf);
1074                         } else {
1075                                 int *ip = va_arg(args, int *);
1076                                 *ip = (str - buf);
1077                         }
1078                         break;
1079                 }
1080
1081                 default:
1082                         switch (spec.type) {
1083                         case FORMAT_TYPE_LONG_LONG:
1084                                 num = va_arg(args, long long);
1085                                 break;
1086                         case FORMAT_TYPE_ULONG:
1087                                 num = va_arg(args, unsigned long);
1088                                 break;
1089                         case FORMAT_TYPE_LONG:
1090                                 num = va_arg(args, long);
1091                                 break;
1092                         case FORMAT_TYPE_SIZE_T:
1093                                 num = va_arg(args, size_t);
1094                                 break;
1095                         case FORMAT_TYPE_PTRDIFF:
1096                                 num = va_arg(args, ptrdiff_t);
1097                                 break;
1098                         case FORMAT_TYPE_USHORT:
1099                                 num = (unsigned short) va_arg(args, int);
1100                                 break;
1101                         case FORMAT_TYPE_SHORT:
1102                                 num = (short) va_arg(args, int);
1103                                 break;
1104                         case FORMAT_TYPE_UINT:
1105                                 num = va_arg(args, unsigned int);
1106                                 break;
1107                         default:
1108                                 num = va_arg(args, unsigned int);
1109                         }
1110
1111                         str = number(str, end, num, spec);
1112                 }
1113         }
1114
1115         if (size > 0) {
1116                 if (str < end)
1117                         *str = '\0';
1118                 else
1119                         end[-1] = '\0';
1120         }
1121
1122         /* the trailing null byte doesn't count towards the total */
1123         return str-buf;
1124
1125 }
1126 EXPORT_SYMBOL(vsnprintf);
1127
1128 /**
1129  * vscnprintf - Format a string and place it in a buffer
1130  * @buf: The buffer to place the result into
1131  * @size: The size of the buffer, including the trailing null space
1132  * @fmt: The format string to use
1133  * @args: Arguments for the format string
1134  *
1135  * The return value is the number of characters which have been written into
1136  * the @buf not including the trailing '\0'. If @size is <= 0 the function
1137  * returns 0.
1138  *
1139  * Call this function if you are already dealing with a va_list.
1140  * You probably want scnprintf() instead.
1141  *
1142  * See the vsnprintf() documentation for format string extensions over C99.
1143  */
1144 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1145 {
1146         int i;
1147
1148         i=vsnprintf(buf,size,fmt,args);
1149         return (i >= size) ? (size - 1) : i;
1150 }
1151 EXPORT_SYMBOL(vscnprintf);
1152
1153 /**
1154  * snprintf - Format a string and place it in a buffer
1155  * @buf: The buffer to place the result into
1156  * @size: The size of the buffer, including the trailing null space
1157  * @fmt: The format string to use
1158  * @...: Arguments for the format string
1159  *
1160  * The return value is the number of characters which would be
1161  * generated for the given input, excluding the trailing null,
1162  * as per ISO C99.  If the return is greater than or equal to
1163  * @size, the resulting string is truncated.
1164  *
1165  * See the vsnprintf() documentation for format string extensions over C99.
1166  */
1167 int snprintf(char * buf, size_t size, const char *fmt, ...)
1168 {
1169         va_list args;
1170         int i;
1171
1172         va_start(args, fmt);
1173         i=vsnprintf(buf,size,fmt,args);
1174         va_end(args);
1175         return i;
1176 }
1177 EXPORT_SYMBOL(snprintf);
1178
1179 /**
1180  * scnprintf - Format a string and place it in a buffer
1181  * @buf: The buffer to place the result into
1182  * @size: The size of the buffer, including the trailing null space
1183  * @fmt: The format string to use
1184  * @...: Arguments for the format string
1185  *
1186  * The return value is the number of characters written into @buf not including
1187  * the trailing '\0'. If @size is <= 0 the function returns 0.
1188  */
1189
1190 int scnprintf(char * buf, size_t size, const char *fmt, ...)
1191 {
1192         va_list args;
1193         int i;
1194
1195         va_start(args, fmt);
1196         i = vsnprintf(buf, size, fmt, args);
1197         va_end(args);
1198         return (i >= size) ? (size - 1) : i;
1199 }
1200 EXPORT_SYMBOL(scnprintf);
1201
1202 /**
1203  * vsprintf - Format a string and place it in a buffer
1204  * @buf: The buffer to place the result into
1205  * @fmt: The format string to use
1206  * @args: Arguments for the format string
1207  *
1208  * The function returns the number of characters written
1209  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1210  * buffer overflows.
1211  *
1212  * Call this function if you are already dealing with a va_list.
1213  * You probably want sprintf() instead.
1214  *
1215  * See the vsnprintf() documentation for format string extensions over C99.
1216  */
1217 int vsprintf(char *buf, const char *fmt, va_list args)
1218 {
1219         return vsnprintf(buf, INT_MAX, fmt, args);
1220 }
1221 EXPORT_SYMBOL(vsprintf);
1222
1223 /**
1224  * sprintf - Format a string and place it in a buffer
1225  * @buf: The buffer to place the result into
1226  * @fmt: The format string to use
1227  * @...: Arguments for the format string
1228  *
1229  * The function returns the number of characters written
1230  * into @buf. Use snprintf() or scnprintf() in order to avoid
1231  * buffer overflows.
1232  *
1233  * See the vsnprintf() documentation for format string extensions over C99.
1234  */
1235 int sprintf(char * buf, const char *fmt, ...)
1236 {
1237         va_list args;
1238         int i;
1239
1240         va_start(args, fmt);
1241         i=vsnprintf(buf, INT_MAX, fmt, args);
1242         va_end(args);
1243         return i;
1244 }
1245 EXPORT_SYMBOL(sprintf);
1246
1247 #ifdef CONFIG_BINARY_PRINTF
1248 /*
1249  * bprintf service:
1250  * vbin_printf() - VA arguments to binary data
1251  * bstr_printf() - Binary data to text string
1252  */
1253
1254 /**
1255  * vbin_printf - Parse a format string and place args' binary value in a buffer
1256  * @bin_buf: The buffer to place args' binary value
1257  * @size: The size of the buffer(by words(32bits), not characters)
1258  * @fmt: The format string to use
1259  * @args: Arguments for the format string
1260  *
1261  * The format follows C99 vsnprintf, except %n is ignored, and its argument
1262  * is skiped.
1263  *
1264  * The return value is the number of words(32bits) which would be generated for
1265  * the given input.
1266  *
1267  * NOTE:
1268  * If the return value is greater than @size, the resulting bin_buf is NOT
1269  * valid for bstr_printf().
1270  */
1271 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1272 {
1273         struct printf_spec spec = {0};
1274         char *str, *end;
1275         int read;
1276
1277         str = (char *)bin_buf;
1278         end = (char *)(bin_buf + size);
1279
1280 #define save_arg(type)                                                  \
1281 do {                                                                    \
1282         if (sizeof(type) == 8) {                                        \
1283                 unsigned long long value;                               \
1284                 str = PTR_ALIGN(str, sizeof(u32));                      \
1285                 value = va_arg(args, unsigned long long);               \
1286                 if (str + sizeof(type) <= end) {                        \
1287                         *(u32 *)str = *(u32 *)&value;                   \
1288                         *(u32 *)(str + 4) = *((u32 *)&value + 1);       \
1289                 }                                                       \
1290         } else {                                                        \
1291                 unsigned long value;                                    \
1292                 str = PTR_ALIGN(str, sizeof(type));                     \
1293                 value = va_arg(args, int);                              \
1294                 if (str + sizeof(type) <= end)                          \
1295                         *(typeof(type) *)str = (type)value;             \
1296         }                                                               \
1297         str += sizeof(type);                                            \
1298 } while (0)
1299
1300
1301         while (*fmt) {
1302                 read = format_decode(fmt, &spec);
1303
1304                 fmt += read;
1305
1306                 switch (spec.type) {
1307                 case FORMAT_TYPE_NONE:
1308                         break;
1309
1310                 case FORMAT_TYPE_WITDH:
1311                 case FORMAT_TYPE_PRECISION:
1312                         save_arg(int);
1313                         break;
1314
1315                 case FORMAT_TYPE_CHAR:
1316                         save_arg(char);
1317                         break;
1318
1319                 case FORMAT_TYPE_STR: {
1320                         const char *save_str = va_arg(args, char *);
1321                         size_t len;
1322                         if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1323                                         || (unsigned long)save_str < PAGE_SIZE)
1324                                 save_str = "<NULL>";
1325                         len = strlen(save_str);
1326                         if (str + len + 1 < end)
1327                                 memcpy(str, save_str, len + 1);
1328                         str += len + 1;
1329                         break;
1330                 }
1331
1332                 case FORMAT_TYPE_PTR:
1333                         save_arg(void *);
1334                         /* skip all alphanumeric pointer suffixes */
1335                         while (isalnum(*fmt))
1336                                 fmt++;
1337                         break;
1338
1339                 case FORMAT_TYPE_PERCENT_CHAR:
1340                         break;
1341
1342                 case FORMAT_TYPE_INVALID:
1343                         if (!*fmt)
1344                                 --fmt;
1345                         break;
1346
1347                 case FORMAT_TYPE_NRCHARS: {
1348                         /* skip %n 's argument */
1349                         int qualifier = spec.qualifier;
1350                         void *skip_arg;
1351                         if (qualifier == 'l')
1352                                 skip_arg = va_arg(args, long *);
1353                         else if (qualifier == 'Z' || qualifier == 'z')
1354                                 skip_arg = va_arg(args, size_t *);
1355                         else
1356                                 skip_arg = va_arg(args, int *);
1357                         break;
1358                 }
1359
1360                 default:
1361                         switch (spec.type) {
1362
1363                         case FORMAT_TYPE_LONG_LONG:
1364                                 save_arg(long long);
1365                                 break;
1366                         case FORMAT_TYPE_ULONG:
1367                         case FORMAT_TYPE_LONG:
1368                                 save_arg(unsigned long);
1369                                 break;
1370                         case FORMAT_TYPE_SIZE_T:
1371                                 save_arg(size_t);
1372                                 break;
1373                         case FORMAT_TYPE_PTRDIFF:
1374                                 save_arg(ptrdiff_t);
1375                                 break;
1376                         case FORMAT_TYPE_USHORT:
1377                         case FORMAT_TYPE_SHORT:
1378                                 save_arg(short);
1379                                 break;
1380                         default:
1381                                 save_arg(int);
1382                         }
1383                 }
1384         }
1385         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1386
1387 #undef save_arg
1388 }
1389 EXPORT_SYMBOL_GPL(vbin_printf);
1390
1391 /**
1392  * bstr_printf - Format a string from binary arguments and place it in a buffer
1393  * @buf: The buffer to place the result into
1394  * @size: The size of the buffer, including the trailing null space
1395  * @fmt: The format string to use
1396  * @bin_buf: Binary arguments for the format string
1397  *
1398  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1399  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1400  * a binary buffer that generated by vbin_printf.
1401  *
1402  * The format follows C99 vsnprintf, but has some extensions:
1403  * %pS output the name of a text symbol
1404  * %pF output the name of a function pointer
1405  * %pR output the address range in a struct resource
1406  * %n is ignored
1407  *
1408  * The return value is the number of characters which would
1409  * be generated for the given input, excluding the trailing
1410  * '\0', as per ISO C99. If you want to have the exact
1411  * number of characters written into @buf as return value
1412  * (not including the trailing '\0'), use vscnprintf(). If the
1413  * return is greater than or equal to @size, the resulting
1414  * string is truncated.
1415  */
1416 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1417 {
1418         unsigned long long num;
1419         char *str, *end, c;
1420         const char *args = (const char *)bin_buf;
1421
1422         struct printf_spec spec = {0};
1423
1424         if (unlikely((int) size < 0)) {
1425                 /* There can be only one.. */
1426                 static char warn = 1;
1427                 WARN_ON(warn);
1428                 warn = 0;
1429                 return 0;
1430         }
1431
1432         str = buf;
1433         end = buf + size;
1434
1435 #define get_arg(type)                                                   \
1436 ({                                                                      \
1437         typeof(type) value;                                             \
1438         if (sizeof(type) == 8) {                                        \
1439                 args = PTR_ALIGN(args, sizeof(u32));                    \
1440                 *(u32 *)&value = *(u32 *)args;                          \
1441                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
1442         } else {                                                        \
1443                 args = PTR_ALIGN(args, sizeof(type));                   \
1444                 value = *(typeof(type) *)args;                          \
1445         }                                                               \
1446         args += sizeof(type);                                           \
1447         value;                                                          \
1448 })
1449
1450         /* Make sure end is always >= buf */
1451         if (end < buf) {
1452                 end = ((void *)-1);
1453                 size = end - buf;
1454         }
1455
1456         while (*fmt) {
1457                 int read;
1458                 const char *old_fmt = fmt;
1459
1460                 read = format_decode(fmt, &spec);
1461
1462                 fmt += read;
1463
1464                 switch (spec.type) {
1465                 case FORMAT_TYPE_NONE: {
1466                         int copy = read;
1467                         if (str < end) {
1468                                 if (copy > end - str)
1469                                         copy = end - str;
1470                                 memcpy(str, old_fmt, copy);
1471                         }
1472                         str += read;
1473                         break;
1474                 }
1475
1476                 case FORMAT_TYPE_WITDH:
1477                         spec.field_width = get_arg(int);
1478                         break;
1479
1480                 case FORMAT_TYPE_PRECISION:
1481                         spec.precision = get_arg(int);
1482                         break;
1483
1484                 case FORMAT_TYPE_CHAR:
1485                         if (!(spec.flags & LEFT)) {
1486                                 while (--spec.field_width > 0) {
1487                                         if (str < end)
1488                                                 *str = ' ';
1489                                         ++str;
1490                                 }
1491                         }
1492                         c = (unsigned char) get_arg(char);
1493                         if (str < end)
1494                                 *str = c;
1495                         ++str;
1496                         while (--spec.field_width > 0) {
1497                                 if (str < end)
1498                                         *str = ' ';
1499                                 ++str;
1500                         }
1501                         break;
1502
1503                 case FORMAT_TYPE_STR: {
1504                         const char *str_arg = args;
1505                         size_t len = strlen(str_arg);
1506                         args += len + 1;
1507                         str = string(str, end, (char *)str_arg, spec);
1508                         break;
1509                 }
1510
1511                 case FORMAT_TYPE_PTR:
1512                         str = pointer(fmt+1, str, end, get_arg(void *), spec);
1513                         while (isalnum(*fmt))
1514                                 fmt++;
1515                         break;
1516
1517                 case FORMAT_TYPE_PERCENT_CHAR:
1518                         if (str < end)
1519                                 *str = '%';
1520                         ++str;
1521                         break;
1522
1523                 case FORMAT_TYPE_INVALID:
1524                         if (str < end)
1525                                 *str = '%';
1526                         ++str;
1527                         if (*fmt) {
1528                                 if (str < end)
1529                                         *str = *fmt;
1530                                 ++str;
1531                         } else {
1532                                 --fmt;
1533                         }
1534                         break;
1535
1536                 case FORMAT_TYPE_NRCHARS:
1537                         /* skip */
1538                         break;
1539
1540                 default:
1541                         switch (spec.type) {
1542
1543                         case FORMAT_TYPE_LONG_LONG:
1544                                 num = get_arg(long long);
1545                                 break;
1546                         case FORMAT_TYPE_ULONG:
1547                                 num = get_arg(unsigned long);
1548                                 break;
1549                         case FORMAT_TYPE_LONG:
1550                                 num = get_arg(unsigned long);
1551                                 break;
1552                         case FORMAT_TYPE_SIZE_T:
1553                                 num = get_arg(size_t);
1554                                 break;
1555                         case FORMAT_TYPE_PTRDIFF:
1556                                 num = get_arg(ptrdiff_t);
1557                                 break;
1558                         case FORMAT_TYPE_USHORT:
1559                                 num = get_arg(unsigned short);
1560                                 break;
1561                         case FORMAT_TYPE_SHORT:
1562                                 num = get_arg(short);
1563                                 break;
1564                         case FORMAT_TYPE_UINT:
1565                                 num = get_arg(unsigned int);
1566                                 break;
1567                         default:
1568                                 num = get_arg(int);
1569                         }
1570
1571                         str = number(str, end, num, spec);
1572                 }
1573         }
1574
1575         if (size > 0) {
1576                 if (str < end)
1577                         *str = '\0';
1578                 else
1579                         end[-1] = '\0';
1580         }
1581
1582 #undef get_arg
1583
1584         /* the trailing null byte doesn't count towards the total */
1585         return str - buf;
1586 }
1587 EXPORT_SYMBOL_GPL(bstr_printf);
1588
1589 /**
1590  * bprintf - Parse a format string and place args' binary value in a buffer
1591  * @bin_buf: The buffer to place args' binary value
1592  * @size: The size of the buffer(by words(32bits), not characters)
1593  * @fmt: The format string to use
1594  * @...: Arguments for the format string
1595  *
1596  * The function returns the number of words(u32) written
1597  * into @bin_buf.
1598  */
1599 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1600 {
1601         va_list args;
1602         int ret;
1603
1604         va_start(args, fmt);
1605         ret = vbin_printf(bin_buf, size, fmt, args);
1606         va_end(args);
1607         return ret;
1608 }
1609 EXPORT_SYMBOL_GPL(bprintf);
1610
1611 #endif /* CONFIG_BINARY_PRINTF */
1612
1613 /**
1614  * vsscanf - Unformat a buffer into a list of arguments
1615  * @buf:        input buffer
1616  * @fmt:        format of buffer
1617  * @args:       arguments
1618  */
1619 int vsscanf(const char * buf, const char * fmt, va_list args)
1620 {
1621         const char *str = buf;
1622         char *next;
1623         char digit;
1624         int num = 0;
1625         int qualifier;
1626         int base;
1627         int field_width;
1628         int is_sign = 0;
1629
1630         while(*fmt && *str) {
1631                 /* skip any white space in format */
1632                 /* white space in format matchs any amount of
1633                  * white space, including none, in the input.
1634                  */
1635                 if (isspace(*fmt)) {
1636                         while (isspace(*fmt))
1637                                 ++fmt;
1638                         while (isspace(*str))
1639                                 ++str;
1640                 }
1641
1642                 /* anything that is not a conversion must match exactly */
1643                 if (*fmt != '%' && *fmt) {
1644                         if (*fmt++ != *str++)
1645                                 break;
1646                         continue;
1647                 }
1648
1649                 if (!*fmt)
1650                         break;
1651                 ++fmt;
1652
1653                 /* skip this conversion.
1654                  * advance both strings to next white space
1655                  */
1656                 if (*fmt == '*') {
1657                         while (!isspace(*fmt) && *fmt)
1658                                 fmt++;
1659                         while (!isspace(*str) && *str)
1660                                 str++;
1661                         continue;
1662                 }
1663
1664                 /* get field width */
1665                 field_width = -1;
1666                 if (isdigit(*fmt))
1667                         field_width = skip_atoi(&fmt);
1668
1669                 /* get conversion qualifier */
1670                 qualifier = -1;
1671                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
1672                     *fmt == 'Z' || *fmt == 'z') {
1673                         qualifier = *fmt++;
1674                         if (unlikely(qualifier == *fmt)) {
1675                                 if (qualifier == 'h') {
1676                                         qualifier = 'H';
1677                                         fmt++;
1678                                 } else if (qualifier == 'l') {
1679                                         qualifier = 'L';
1680                                         fmt++;
1681                                 }
1682                         }
1683                 }
1684                 base = 10;
1685                 is_sign = 0;
1686
1687                 if (!*fmt || !*str)
1688                         break;
1689
1690                 switch(*fmt++) {
1691                 case 'c':
1692                 {
1693                         char *s = (char *) va_arg(args,char*);
1694                         if (field_width == -1)
1695                                 field_width = 1;
1696                         do {
1697                                 *s++ = *str++;
1698                         } while (--field_width > 0 && *str);
1699                         num++;
1700                 }
1701                 continue;
1702                 case 's':
1703                 {
1704                         char *s = (char *) va_arg(args, char *);
1705                         if(field_width == -1)
1706                                 field_width = INT_MAX;
1707                         /* first, skip leading white space in buffer */
1708                         while (isspace(*str))
1709                                 str++;
1710
1711                         /* now copy until next white space */
1712                         while (*str && !isspace(*str) && field_width--) {
1713                                 *s++ = *str++;
1714                         }
1715                         *s = '\0';
1716                         num++;
1717                 }
1718                 continue;
1719                 case 'n':
1720                         /* return number of characters read so far */
1721                 {
1722                         int *i = (int *)va_arg(args,int*);
1723                         *i = str - buf;
1724                 }
1725                 continue;
1726                 case 'o':
1727                         base = 8;
1728                         break;
1729                 case 'x':
1730                 case 'X':
1731                         base = 16;
1732                         break;
1733                 case 'i':
1734                         base = 0;
1735                 case 'd':
1736                         is_sign = 1;
1737                 case 'u':
1738                         break;
1739                 case '%':
1740                         /* looking for '%' in str */
1741                         if (*str++ != '%')
1742                                 return num;
1743                         continue;
1744                 default:
1745                         /* invalid format; stop here */
1746                         return num;
1747                 }
1748
1749                 /* have some sort of integer conversion.
1750                  * first, skip white space in buffer.
1751                  */
1752                 while (isspace(*str))
1753                         str++;
1754
1755                 digit = *str;
1756                 if (is_sign && digit == '-')
1757                         digit = *(str + 1);
1758
1759                 if (!digit
1760                     || (base == 16 && !isxdigit(digit))
1761                     || (base == 10 && !isdigit(digit))
1762                     || (base == 8 && (!isdigit(digit) || digit > '7'))
1763                     || (base == 0 && !isdigit(digit)))
1764                                 break;
1765
1766                 switch(qualifier) {
1767                 case 'H':       /* that's 'hh' in format */
1768                         if (is_sign) {
1769                                 signed char *s = (signed char *) va_arg(args,signed char *);
1770                                 *s = (signed char) simple_strtol(str,&next,base);
1771                         } else {
1772                                 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
1773                                 *s = (unsigned char) simple_strtoul(str, &next, base);
1774                         }
1775                         break;
1776                 case 'h':
1777                         if (is_sign) {
1778                                 short *s = (short *) va_arg(args,short *);
1779                                 *s = (short) simple_strtol(str,&next,base);
1780                         } else {
1781                                 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
1782                                 *s = (unsigned short) simple_strtoul(str, &next, base);
1783                         }
1784                         break;
1785                 case 'l':
1786                         if (is_sign) {
1787                                 long *l = (long *) va_arg(args,long *);
1788                                 *l = simple_strtol(str,&next,base);
1789                         } else {
1790                                 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
1791                                 *l = simple_strtoul(str,&next,base);
1792                         }
1793                         break;
1794                 case 'L':
1795                         if (is_sign) {
1796                                 long long *l = (long long*) va_arg(args,long long *);
1797                                 *l = simple_strtoll(str,&next,base);
1798                         } else {
1799                                 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
1800                                 *l = simple_strtoull(str,&next,base);
1801                         }
1802                         break;
1803                 case 'Z':
1804                 case 'z':
1805                 {
1806                         size_t *s = (size_t*) va_arg(args,size_t*);
1807                         *s = (size_t) simple_strtoul(str,&next,base);
1808                 }
1809                 break;
1810                 default:
1811                         if (is_sign) {
1812                                 int *i = (int *) va_arg(args, int*);
1813                                 *i = (int) simple_strtol(str,&next,base);
1814                         } else {
1815                                 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
1816                                 *i = (unsigned int) simple_strtoul(str,&next,base);
1817                         }
1818                         break;
1819                 }
1820                 num++;
1821
1822                 if (!next)
1823                         break;
1824                 str = next;
1825         }
1826
1827         /*
1828          * Now we've come all the way through so either the input string or the
1829          * format ended. In the former case, there can be a %n at the current
1830          * position in the format that needs to be filled.
1831          */
1832         if (*fmt == '%' && *(fmt + 1) == 'n') {
1833                 int *p = (int *)va_arg(args, int *);
1834                 *p = str - buf;
1835         }
1836
1837         return num;
1838 }
1839 EXPORT_SYMBOL(vsscanf);
1840
1841 /**
1842  * sscanf - Unformat a buffer into a list of arguments
1843  * @buf:        input buffer
1844  * @fmt:        formatting of buffer
1845  * @...:        resulting arguments
1846  */
1847 int sscanf(const char * buf, const char * fmt, ...)
1848 {
1849         va_list args;
1850         int i;
1851
1852         va_start(args,fmt);
1853         i = vsscanf(buf,fmt,args);
1854         va_end(args);
1855         return i;
1856 }
1857 EXPORT_SYMBOL(sscanf);