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 #include <stdarg.h>
  13 #include <linux/types.h>
  14 #include <linux/string.h>
  15 #include <linux/ctype.h>
  16 #include <asm-generic/div64.h>
  17 #include <malloc.h>
  18
  19 #include <common.h>
  20 #include <reloc.h>
  21
  22 unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)
  23 {
  24         unsigned long result = 0,value;
  25
  26         if (*cp == '0') {
  27                 cp++;
  28                 if ((*cp == 'x') && isxdigit(cp[1])) {
  29                         base = 16;
  30                         cp++;
  31                 }
  32                 if (!base) {
  33                         base = 8;
  34                 }
  35         }
  36         if (!base) {
  37                 base = 10;
  38         }
  39         while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
  40             ? toupper(*cp) : *cp)-'A'+10) < base) {
  41                 result = result*base + value;
  42                 cp++;
  43         }
  44         if (endp)
  45                 *endp = (char *)cp;
  46         return result;
  47 }
  48 EXPORT_SYMBOL(simple_strtoul);
  49
  50 long simple_strtol(const char *cp,char **endp,unsigned int base)
  51 {
  52         if(*cp=='-')
  53                 return -simple_strtoul(cp+1,endp,base);
  54         return simple_strtoul(cp,endp,base);
  55 }
  56 EXPORT_SYMBOL(simple_strtol);
  57
  58 #ifdef CFG_64BIT_STRTOUL
  59 unsigned long long simple_strtoull (const char *cp, char **endp, unsigned int base)
  60 {
  61         unsigned long long result = 0, value;
  62
  63         if (*cp == '0') {
  64                 cp++;
  65                 if ((*cp == 'x') && isxdigit (cp[1])) {
  66                         base = 16;
  67                         cp++;
  68                 }
  69                 if (!base) {
  70                         base = 8;
  71                 }
  72         }
  73         if (!base) {
  74                 base = 10;
  75         }
  76         while (isxdigit (*cp) && (value = isdigit (*cp)
  77                                 ? *cp - '0'
  78                                 : (islower (*cp) ? toupper (*cp) : *cp) - 'A' + 10) < base) {
  79                 result = result * base + value;
  80                 cp++;
  81         }
  82         if (endp)
  83                 *endp = (char *) cp;
  84         return result;
  85 }
  86 #endif /* CFG_64BIT_STRTOUL */
  87
  88 /* we use this so that we can do without the ctype library */
  89 #define is_digit(c)     ((c) >= '0' && (c) <= '9')
  90
  91 static int skip_atoi(const char **s)
  92 {
  93         int i=0;
  94
  95         while (is_digit(**s))
  96                 i = i*10 + *((*s)++) - '0';
  97         return i;
  98 }
  99
 100 #define ZEROPAD 1               /* pad with zero */
 101 #define SIGN    2               /* unsigned/signed long */
 102 #define PLUS    4               /* show plus */
 103 #define SPACE   8               /* space if plus */
 104 #define LEFT    16              /* left justified */
 105 #define SMALL   32              /* Must be 32 == 0x20 */
 106 #define SPECIAL 64              /* 0x */
 107
 108 static char *number(char *buf, char *end, unsigned long long num, int base, int size, int precision, int type)
 109 {
 110         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 111         static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 112
 113         char tmp[66];
 114         char sign;
 115         char locase;
 116         int need_pfx = ((type & SPECIAL) && base != 10);
 117         int i;
 118
 119         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 120          * produces same digits or (maybe lowercased) letters */
 121         locase = (type & SMALL);
 122         if (type & LEFT)
 123                 type &= ~ZEROPAD;
 124         sign = 0;
 125         if (type & SIGN) {
 126                 if ((signed long long) num < 0) {
 127                         sign = '-';
 128                         num = - (signed long long) num;
 129                         size--;
 130                 } else if (type & PLUS) {
 131                         sign = '+';
 132                         size--;
 133                 } else if (type & SPACE) {
 134                         sign = ' ';
 135                         size--;
 136                 }
 137         }
 138         if (need_pfx) {
 139                 size--;
 140                 if (base == 16)
 141                         size--;
 142         }
 143         /* generate full string in tmp[], in reverse order */
 144         i = 0;
 145         if (num == 0)
 146                 tmp[i++] = '0';
 147         else do {
 148                 tmp[i++] = (digits[do_div(num,base)] | locase);
 149         } while (num != 0);
 150
 151         /* printing 100 using %2d gives "100", not "00" */
 152         if (i > precision)
 153                 precision = i;
 154         size -= precision;
 155         if (!(type & (ZEROPAD+LEFT))) {
 156                 while(--size >= 0) {
 157                         if (buf < end)
 158                                 *buf = ' ';
 159                         ++buf;
 160                 }
 161         }
 162         /* sign */
 163         if (sign) {
 164                 if (buf < end)
 165                         *buf = sign;
 166                 ++buf;
 167         }
 168         /* "0x" / "0" prefix */
 169         if (need_pfx) {
 170                 if (buf < end)
 171                         *buf = '0';
 172                 ++buf;
 173                 if (base == 16) {
 174                         if (buf < end)
 175                                 *buf = ('X' | locase);
 176                         ++buf;
 177                 }
 178         }
 179         /* zero or space padding */
 180         if (!(type & LEFT)) {
 181                 char c = (type & ZEROPAD) ? '0' : ' ';
 182                 while (--size >= 0) {
 183                         if (buf < end)
 184                                 *buf = c;
 185                         ++buf;
 186                 }
 187         }
 188         /* hmm even more zero padding? */
 189         while (i <= --precision) {
 190                 if (buf < end)
 191                         *buf = '0';
 192                 ++buf;
 193         }
 194         /* actual digits of result */
 195         while (--i >= 0) {
 196                 if (buf < end)
 197                         *buf = tmp[i];
 198                 ++buf;
 199         }
 200         /* trailing space padding */
 201         while (--size >= 0) {
 202                 if (buf < end)
 203                         *buf = ' ';
 204                 ++buf;
 205         }
 206         return buf;
 207 }
 208
 209 #ifndef PAGE_SIZE
 210 #define PAGE_SIZE 4096
 211 #endif
 212
 213 static char *string(char *buf, char *end, char *s, int field_width, int precision, int flags)
 214 {
 215         int len, i;
 216
 217         if ((unsigned long)s < PAGE_SIZE)
 218                 s = "<NULL>";
 219
 220         len = strnlen(s, precision);
 221
 222         if (!(flags & LEFT)) {
 223                 while (len < field_width--) {
 224                         if (buf < end)
 225                                 *buf = ' ';
 226                         ++buf;
 227                 }
 228         }
 229         for (i = 0; i < len; ++i) {
 230                 if (buf < end)
 231                         *buf = *s;
 232                 ++buf; ++s;
 233         }
 234         while (len < field_width--) {
 235                 if (buf < end)
 236                         *buf = ' ';
 237                 ++buf;
 238         }
 239         return buf;
 240 }
 241
 242 static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags)
 243 {
 244         unsigned long value = (unsigned long) ptr;
 245 #ifdef CONFIG_KALLSYMS
 246         char sym[KSYM_SYMBOL_LEN];
 247         sprint_symbol(sym, value);
 248         return string(buf, end, sym, field_width, precision, flags);
 249 #else
 250         field_width = 2*sizeof(void *);
 251         flags |= SPECIAL | SMALL | ZEROPAD;
 252         return number(buf, end, value, 16, field_width, precision, flags);
 253 #endif
 254 }
 255
 256 /*
 257  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 258  * by an extra set of alphanumeric characters that are extended format
 259  * specifiers.
 260  *
 261  * Right now we handle:
 262  *
 263  * - 'S' For symbolic direct pointers
 264  *
 265  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 266  * function pointers are really function descriptors, which contain a
 267  * pointer to the real address.
 268  */
 269 static char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field_width, int precision, int flags)
 270 {
 271         switch (*fmt) {
 272         case 'S':
 273                 return symbol_string(buf, end, ptr, field_width, precision, flags);
 274         }
 275         flags |= SMALL;
 276         if (field_width == -1) {
 277                 field_width = 2*sizeof(void *);
 278                 flags |= ZEROPAD;
 279         }
 280         return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags);
 281 }
 282
 283 /**
 284  * vsnprintf - Format a string and place it in a buffer
 285  * @buf: The buffer to place the result into
 286  * @size: The size of the buffer, including the trailing null space
 287  * @fmt: The format string to use
 288  * @args: Arguments for the format string
 289  *
 290  * This function follows C99 vsnprintf, but has some extensions:
 291  * %pS output the name of a text symbol
 292  * %pF output the name of a function pointer
 293  * %pR output the address range in a struct resource
 294  *
 295  * The return value is the number of characters which would
 296  * be generated for the given input, excluding the trailing
 297  * '\0', as per ISO C99. If you want to have the exact
 298  * number of characters written into @buf as return value
 299  * (not including the trailing '\0'), use vscnprintf(). If the
 300  * return is greater than or equal to @size, the resulting
 301  * string is truncated.
 302  *
 303  * Call this function if you are already dealing with a va_list.
 304  * You probably want snprintf() instead.
 305  */
 306 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 307 {
 308         unsigned long long num;
 309         int base;
 310         char *str, *end, c;
 311
 312         int flags;              /* flags to number() */
 313
 314         int field_width;        /* width of output field */
 315         int precision;          /* min. # of digits for integers; max
 316                                    number of chars for from string */
 317         int qualifier;          /* 'h', 'l', or 'L' for integer fields */
 318                                 /* 'z' support added 23/7/1999 S.H.    */
 319                                 /* 'z' changed to 'Z' --davidm 1/25/99 */
 320                                 /* 't' added for ptrdiff_t */
 321
 322         /* Reject out-of-range values early.  Large positive sizes are
 323            used for unknown buffer sizes. */
 324         if (unlikely((int) size < 0))
 325                 return 0;
 326
 327         str = buf;
 328         end = buf + size;
 329
 330         /* Make sure end is always >= buf */
 331         if (end < buf) {
 332                 end = ((void *)-1);
 333                 size = end - buf;
 334         }
 335
 336         for (; *fmt ; ++fmt) {
 337                 if (*fmt != '%') {
 338                         if (str < end)
 339                                 *str = *fmt;
 340                         ++str;
 341                         continue;
 342                 }
 343
 344                 /* process flags */
 345                 flags = 0;
 346                 repeat:
 347                         ++fmt;          /* this also skips first '%' */
 348                         switch (*fmt) {
 349                                 case '-': flags |= LEFT; goto repeat;
 350                                 case '+': flags |= PLUS; goto repeat;
 351                                 case ' ': flags |= SPACE; goto repeat;
 352                                 case '#': flags |= SPECIAL; goto repeat;
 353                                 case '0': flags |= ZEROPAD; goto repeat;
 354                         }
 355
 356                 /* get field width */
 357                 field_width = -1;
 358                 if (isdigit(*fmt))
 359                         field_width = skip_atoi(&fmt);
 360                 else if (*fmt == '*') {
 361                         ++fmt;
 362                         /* it's the next argument */
 363                         field_width = va_arg(args, int);
 364                         if (field_width < 0) {
 365                                 field_width = -field_width;
 366                                 flags |= LEFT;
 367                         }
 368                 }
 369
 370                 /* get the precision */
 371                 precision = -1;
 372                 if (*fmt == '.') {
 373                         ++fmt;
 374                         if (isdigit(*fmt))
 375                                 precision = skip_atoi(&fmt);
 376                         else if (*fmt == '*') {
 377                                 ++fmt;
 378                                 /* it's the next argument */
 379                                 precision = va_arg(args, int);
 380                         }
 381                         if (precision < 0)
 382                                 precision = 0;
 383                 }
 384
 385                 /* get the conversion qualifier */
 386                 qualifier = -1;
 387                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 388                     *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
 389                         qualifier = *fmt;
 390                         ++fmt;
 391                         if (qualifier == 'l' && *fmt == 'l') {
 392                                 qualifier = 'L';
 393                                 ++fmt;
 394                         }
 395                 }
 396
 397                 /* default base */
 398                 base = 10;
 399
 400                 switch (*fmt) {
 401                         case 'c':
 402                                 if (!(flags & LEFT)) {
 403                                         while (--field_width > 0) {
 404                                                 if (str < end)
 405                                                         *str = ' ';
 406                                                 ++str;
 407                                         }
 408                                 }
 409                                 c = (unsigned char) va_arg(args, int);
 410                                 if (str < end)
 411                                         *str = c;
 412                                 ++str;
 413                                 while (--field_width > 0) {
 414                                         if (str < end)
 415                                                 *str = ' ';
 416                                         ++str;
 417                                 }
 418                                 continue;
 419
 420                         case 's':
 421                                 str = string(str, end, va_arg(args, char *), field_width, precision, flags);
 422                                 continue;
 423
 424                         case 'p':
 425                                 str = pointer(fmt+1, str, end,
 426                                                 va_arg(args, void *),
 427                                                 field_width, precision, flags);
 428                                 /* Skip all alphanumeric pointer suffixes */
 429                                 while (isalnum(fmt[1]))
 430                                         fmt++;
 431                                 continue;
 432
 433                         case 'n':
 434                                 /* FIXME:
 435                                 * What does C99 say about the overflow case here? */
 436                                 if (qualifier == 'l') {
 437                                         long * ip = va_arg(args, long *);
 438                                         *ip = (str - buf);
 439                                 } else if (qualifier == 'Z' || qualifier == 'z') {
 440                                         size_t * ip = va_arg(args, size_t *);
 441                                         *ip = (str - buf);
 442                                 } else {
 443                                         int * ip = va_arg(args, int *);
 444                                         *ip = (str - buf);
 445                                 }
 446                                 continue;
 447
 448                         case '%':
 449                                 if (str < end)
 450                                         *str = '%';
 451                                 ++str;
 452                                 continue;
 453
 454                                 /* integer number formats - set up the flags and "break" */
 455                         case 'o':
 456                                 base = 8;
 457                                 break;
 458
 459                         case 'x':
 460                                 flags |= SMALL;
 461                         case 'X':
 462                                 base = 16;
 463                                 break;
 464
 465                         case 'd':
 466                         case 'i':
 467                                 flags |= SIGN;
 468                         case 'u':
 469                                 break;
 470
 471                         default:
 472                                 if (str < end)
 473                                         *str = '%';
 474                                 ++str;
 475                                 if (*fmt) {
 476                                         if (str < end)
 477                                                 *str = *fmt;
 478                                         ++str;
 479                                 } else {
 480                                         --fmt;
 481                                 }
 482                                 continue;
 483                 }
 484                 if (qualifier == 'L')
 485                         num = va_arg(args, long long);
 486                 else if (qualifier == 'l') {
 487                         num = va_arg(args, unsigned long);
 488                         if (flags & SIGN)
 489                                 num = (signed long) num;
 490                 } else if (qualifier == 'Z' || qualifier == 'z') {
 491                         num = va_arg(args, size_t);
 492                 } else if (qualifier == 't') {
 493                         num = va_arg(args, ptrdiff_t);
 494                 } else if (qualifier == 'h') {
 495                         num = (unsigned short) va_arg(args, int);
 496                         if (flags & SIGN)
 497                                 num = (signed short) num;
 498                 } else {
 499                         num = va_arg(args, unsigned int);
 500                         if (flags & SIGN)
 501                                 num = (signed int) num;
 502                 }
 503                 str = number(str, end, num, base,
 504                                 field_width, precision, flags);
 505         }
 506         if (size > 0) {
 507                 if (str < end)
 508                         *str = '\0';
 509                 else
 510                         end[-1] = '\0';
 511         }
 512         /* the trailing null byte doesn't count towards the total */
 513         return str-buf;
 514 }
 515 EXPORT_SYMBOL(vsnprintf);
 516
 517 /**
 518  * vscnprintf - Format a string and place it in a buffer
 519  * @buf: The buffer to place the result into
 520  * @size: The size of the buffer, including the trailing null space
 521  * @fmt: The format string to use
 522  * @args: Arguments for the format string
 523  *
 524  * The return value is the number of characters which have been written into
 525  * the @buf not including the trailing '\0'. If @size is <= 0 the function
 526  * returns 0.
 527  *
 528  * Call this function if you are already dealing with a va_list.
 529  * You probably want scnprintf() instead.
 530  *
 531  * See the vsnprintf() documentation for format string extensions over C99.
 532  */
 533 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 534 {
 535         int i;
 536
 537         i=vsnprintf(buf,size,fmt,args);
 538         return (i >= size) ? (size - 1) : i;
 539 }
 540 EXPORT_SYMBOL(vscnprintf);
 541
 542 /**
 543  * vsprintf - Format a string and place it in a buffer
 544  * @buf: The buffer to place the result into
 545  * @fmt: The format string to use
 546  * @args: Arguments for the format string
 547  *
 548  * The function returns the number of characters written
 549  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
 550  * buffer overflows.
 551  *
 552  * Call this function if you are already dealing with a va_list.
 553  * You probably want sprintf() instead.
 554  *
 555  * See the vsnprintf() documentation for format string extensions over C99.
 556  */
 557 int vsprintf(char *buf, const char *fmt, va_list args)
 558 {
 559         return vsnprintf(buf, INT_MAX, fmt, args);
 560 }
 561 EXPORT_SYMBOL(vsprintf);
 562
 563 int sprintf(char * buf, const char *fmt, ...)
 564 {
 565         va_list args;
 566         int i;
 567
 568         va_start(args, fmt);
 569         i=vsprintf(buf,fmt,args);
 570         va_end(args);
 571         return i;
 572 }
 573 EXPORT_SYMBOL(sprintf);
 574
 575 int snprintf(char * buf, size_t size, const char *fmt, ...)
 576 {
 577         va_list args;
 578         int i;
 579
 580         va_start(args, fmt);
 581         i = vsnprintf(buf, size, fmt, args);
 582         va_end(args);
 583         return i;
 584 }
 585 EXPORT_SYMBOL(sprintf);
 586
 587 /* Simplified asprintf. */
 588 char *vasprintf(const char *fmt, va_list ap)
 589 {
 590         unsigned int len;
 591         char *p;
 592         va_list aq;
 593
 594         va_copy(aq, ap);
 595         len = vsnprintf(NULL, 0, fmt, aq);
 596         va_end(aq);
 597
 598         p = malloc(len + 1);
 599         if (!p)
 600                 return NULL;
 601
 602         vsnprintf(p, len + 1, fmt, ap);
 603
 604         return p;
 605 }
 606 EXPORT_SYMBOL(vasprintf);
 607
 608 char *asprintf(const char *fmt, ...)
 609 {
 610         va_list ap;
 611         char *p;
 612
 613         va_start(ap, fmt);
 614         p = vasprintf(fmt, ap);
 615         va_end(ap);
 616
 617         return p;
 618 }
 619 EXPORT_SYMBOL(asprintf);
 620
 621 void __noreturn panic(const char *fmt, ...)
 622 {
 623         va_list args;
 624         va_start(args, fmt);
 625         vprintf(fmt, args);
 626         putchar('\n');
 627         va_end(args);
 628 #if defined (CONFIG_PANIC_HANG)
 629         hang();
 630 #else
 631         udelay(100000); /* allow messages to go out */
 632         reset_cpu(0);
 633 #endif
 634 }
 635 EXPORT_SYMBOL(panic);