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 #define PAGE_SIZE 4096
 210
 211 static char *string(char *buf, char *end, char *s, int field_width, int precision, int flags)
 212 {
 213         int len, i;
 214
 215         if ((unsigned long)s < PAGE_SIZE)
 216                 s = "<NULL>";
 217
 218         len = strnlen(s, precision);
 219
 220         if (!(flags & LEFT)) {
 221                 while (len < field_width--) {
 222                         if (buf < end)
 223                                 *buf = ' ';
 224                         ++buf;
 225                 }
 226         }
 227         for (i = 0; i < len; ++i) {
 228                 if (buf < end)
 229                         *buf = *s;
 230                 ++buf; ++s;
 231         }
 232         while (len < field_width--) {
 233                 if (buf < end)
 234                         *buf = ' ';
 235                 ++buf;
 236         }
 237         return buf;
 238 }
 239
 240 static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags)
 241 {
 242         unsigned long value = (unsigned long) ptr;
 243 #ifdef CONFIG_KALLSYMS
 244         char sym[KSYM_SYMBOL_LEN];
 245         sprint_symbol(sym, value);
 246         return string(buf, end, sym, field_width, precision, flags);
 247 #else
 248         field_width = 2*sizeof(void *);
 249         flags |= SPECIAL | SMALL | ZEROPAD;
 250         return number(buf, end, value, 16, field_width, precision, flags);
 251 #endif
 252 }
 253
 254 /*
 255  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 256  * by an extra set of alphanumeric characters that are extended format
 257  * specifiers.
 258  *
 259  * Right now we handle:
 260  *
 261  * - 'S' For symbolic direct pointers
 262  *
 263  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 264  * function pointers are really function descriptors, which contain a
 265  * pointer to the real address.
 266  */
 267 static char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field_width, int precision, int flags)
 268 {
 269         switch (*fmt) {
 270         case 'S':
 271                 return symbol_string(buf, end, ptr, field_width, precision, flags);
 272         }
 273         flags |= SMALL;
 274         if (field_width == -1) {
 275                 field_width = 2*sizeof(void *);
 276                 flags |= ZEROPAD;
 277         }
 278         return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags);
 279 }
 280
 281 /**
 282  * vsnprintf - Format a string and place it in a buffer
 283  * @buf: The buffer to place the result into
 284  * @size: The size of the buffer, including the trailing null space
 285  * @fmt: The format string to use
 286  * @args: Arguments for the format string
 287  *
 288  * This function follows C99 vsnprintf, but has some extensions:
 289  * %pS output the name of a text symbol
 290  * %pF output the name of a function pointer
 291  * %pR output the address range in a struct resource
 292  *
 293  * The return value is the number of characters which would
 294  * be generated for the given input, excluding the trailing
 295  * '\0', as per ISO C99. If you want to have the exact
 296  * number of characters written into @buf as return value
 297  * (not including the trailing '\0'), use vscnprintf(). If the
 298  * return is greater than or equal to @size, the resulting
 299  * string is truncated.
 300  *
 301  * Call this function if you are already dealing with a va_list.
 302  * You probably want snprintf() instead.
 303  */
 304 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 305 {
 306         unsigned long long num;
 307         int base;
 308         char *str, *end, c;
 309
 310         int flags;              /* flags to number() */
 311
 312         int field_width;        /* width of output field */
 313         int precision;          /* min. # of digits for integers; max
 314                                    number of chars for from string */
 315         int qualifier;          /* 'h', 'l', or 'L' for integer fields */
 316                                 /* 'z' support added 23/7/1999 S.H.    */
 317                                 /* 'z' changed to 'Z' --davidm 1/25/99 */
 318                                 /* 't' added for ptrdiff_t */
 319
 320         /* Reject out-of-range values early.  Large positive sizes are
 321            used for unknown buffer sizes. */
 322         if (unlikely((int) size < 0))
 323                 return 0;
 324
 325         str = buf;
 326         end = buf + size;
 327
 328         /* Make sure end is always >= buf */
 329         if (end < buf) {
 330                 end = ((void *)-1);
 331                 size = end - buf;
 332         }
 333
 334         for (; *fmt ; ++fmt) {
 335                 if (*fmt != '%') {
 336                         if (str < end)
 337                                 *str = *fmt;
 338                         ++str;
 339                         continue;
 340                 }
 341
 342                 /* process flags */
 343                 flags = 0;
 344                 repeat:
 345                         ++fmt;          /* this also skips first '%' */
 346                         switch (*fmt) {
 347                                 case '-': flags |= LEFT; goto repeat;
 348                                 case '+': flags |= PLUS; goto repeat;
 349                                 case ' ': flags |= SPACE; goto repeat;
 350                                 case '#': flags |= SPECIAL; goto repeat;
 351                                 case '0': flags |= ZEROPAD; goto repeat;
 352                         }
 353
 354                 /* get field width */
 355                 field_width = -1;
 356                 if (isdigit(*fmt))
 357                         field_width = skip_atoi(&fmt);
 358                 else if (*fmt == '*') {
 359                         ++fmt;
 360                         /* it's the next argument */
 361                         field_width = va_arg(args, int);
 362                         if (field_width < 0) {
 363                                 field_width = -field_width;
 364                                 flags |= LEFT;
 365                         }
 366                 }
 367
 368                 /* get the precision */
 369                 precision = -1;
 370                 if (*fmt == '.') {
 371                         ++fmt;
 372                         if (isdigit(*fmt))
 373                                 precision = skip_atoi(&fmt);
 374                         else if (*fmt == '*') {
 375                                 ++fmt;
 376                                 /* it's the next argument */
 377                                 precision = va_arg(args, int);
 378                         }
 379                         if (precision < 0)
 380                                 precision = 0;
 381                 }
 382
 383                 /* get the conversion qualifier */
 384                 qualifier = -1;
 385                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 386                     *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
 387                         qualifier = *fmt;
 388                         ++fmt;
 389                         if (qualifier == 'l' && *fmt == 'l') {
 390                                 qualifier = 'L';
 391                                 ++fmt;
 392                         }
 393                 }
 394
 395                 /* default base */
 396                 base = 10;
 397
 398                 switch (*fmt) {
 399                         case 'c':
 400                                 if (!(flags & LEFT)) {
 401                                         while (--field_width > 0) {
 402                                                 if (str < end)
 403                                                         *str = ' ';
 404                                                 ++str;
 405                                         }
 406                                 }
 407                                 c = (unsigned char) va_arg(args, int);
 408                                 if (str < end)
 409                                         *str = c;
 410                                 ++str;
 411                                 while (--field_width > 0) {
 412                                         if (str < end)
 413                                                 *str = ' ';
 414                                         ++str;
 415                                 }
 416                                 continue;
 417
 418                         case 's':
 419                                 str = string(str, end, va_arg(args, char *), field_width, precision, flags);
 420                                 continue;
 421
 422                         case 'p':
 423                                 str = pointer(fmt+1, str, end,
 424                                                 va_arg(args, void *),
 425                                                 field_width, precision, flags);
 426                                 /* Skip all alphanumeric pointer suffixes */
 427                                 while (isalnum(fmt[1]))
 428                                         fmt++;
 429                                 continue;
 430
 431                         case 'n':
 432                                 /* FIXME:
 433                                 * What does C99 say about the overflow case here? */
 434                                 if (qualifier == 'l') {
 435                                         long * ip = va_arg(args, long *);
 436                                         *ip = (str - buf);
 437                                 } else if (qualifier == 'Z' || qualifier == 'z') {
 438                                         size_t * ip = va_arg(args, size_t *);
 439                                         *ip = (str - buf);
 440                                 } else {
 441                                         int * ip = va_arg(args, int *);
 442                                         *ip = (str - buf);
 443                                 }
 444                                 continue;
 445
 446                         case '%':
 447                                 if (str < end)
 448                                         *str = '%';
 449                                 ++str;
 450                                 continue;
 451
 452                                 /* integer number formats - set up the flags and "break" */
 453                         case 'o':
 454                                 base = 8;
 455                                 break;
 456
 457                         case 'x':
 458                                 flags |= SMALL;
 459                         case 'X':
 460                                 base = 16;
 461                                 break;
 462
 463                         case 'd':
 464                         case 'i':
 465                                 flags |= SIGN;
 466                         case 'u':
 467                                 break;
 468
 469                         default:
 470                                 if (str < end)
 471                                         *str = '%';
 472                                 ++str;
 473                                 if (*fmt) {
 474                                         if (str < end)
 475                                                 *str = *fmt;
 476                                         ++str;
 477                                 } else {
 478                                         --fmt;
 479                                 }
 480                                 continue;
 481                 }
 482                 if (qualifier == 'L')
 483                         num = va_arg(args, long long);
 484                 else if (qualifier == 'l') {
 485                         num = va_arg(args, unsigned long);
 486                         if (flags & SIGN)
 487                                 num = (signed long) num;
 488                 } else if (qualifier == 'Z' || qualifier == 'z') {
 489                         num = va_arg(args, size_t);
 490                 } else if (qualifier == 't') {
 491                         num = va_arg(args, ptrdiff_t);
 492                 } else if (qualifier == 'h') {
 493                         num = (unsigned short) va_arg(args, int);
 494                         if (flags & SIGN)
 495                                 num = (signed short) num;
 496                 } else {
 497                         num = va_arg(args, unsigned int);
 498                         if (flags & SIGN)
 499                                 num = (signed int) num;
 500                 }
 501                 str = number(str, end, num, base,
 502                                 field_width, precision, flags);
 503         }
 504         if (size > 0) {
 505                 if (str < end)
 506                         *str = '\0';
 507                 else
 508                         end[-1] = '\0';
 509         }
 510         /* the trailing null byte doesn't count towards the total */
 511         return str-buf;
 512 }
 513 EXPORT_SYMBOL(vsnprintf);
 514
 515 /**
 516  * vsprintf - Format a string and place it in a buffer
 517  * @buf: The buffer to place the result into
 518  * @fmt: The format string to use
 519  * @args: Arguments for the format string
 520  *
 521  * The function returns the number of characters written
 522  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
 523  * buffer overflows.
 524  *
 525  * Call this function if you are already dealing with a va_list.
 526  * You probably want sprintf() instead.
 527  *
 528  * See the vsnprintf() documentation for format string extensions over C99.
 529  */
 530 int vsprintf(char *buf, const char *fmt, va_list args)
 531 {
 532         return vsnprintf(buf, INT_MAX, fmt, args);
 533 }
 534 EXPORT_SYMBOL(vsprintf);
 535
 536 int sprintf(char * buf, const char *fmt, ...)
 537 {
 538         va_list args;
 539         int i;
 540
 541         va_start(args, fmt);
 542         i=vsprintf(buf,fmt,args);
 543         va_end(args);
 544         return i;
 545 }
 546 EXPORT_SYMBOL(sprintf);
 547
 548 /* Simplified asprintf. */
 549 char *vasprintf(const char *fmt, va_list ap)
 550 {
 551         unsigned int len;
 552         char *p;
 553         va_list aq;
 554
 555         va_copy(aq, ap);
 556         len = vsnprintf(NULL, 0, fmt, aq);
 557         va_end(aq);
 558
 559         p = malloc(len + 1);
 560         if (!p)
 561                 return NULL;
 562
 563         vsnprintf(p, len + 1, fmt, ap);
 564
 565         return p;
 566 }
 567 EXPORT_SYMBOL(vasprintf);
 568
 569 char *asprintf(const char *fmt, ...)
 570 {
 571         va_list ap;
 572         char *p;
 573
 574         va_start(ap, fmt);
 575         p = vasprintf(fmt, ap);
 576         va_end(ap);
 577
 578         return p;
 579 }
 580 EXPORT_SYMBOL(asprintf);
 581
 582 void panic(const char *fmt, ...)
 583 {
 584         va_list args;
 585         va_start(args, fmt);
 586         vprintf(fmt, args);
 587         putchar('\n');
 588         va_end(args);
 589 #if defined (CONFIG_PANIC_HANG)
 590         hang();
 591 #else
 592         udelay(100000); /* allow messages to go out */
 593         reset_cpu(0);
 594 #endif
 595 }
 596 EXPORT_SYMBOL(panic);