lib_generic/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
  17 #include <common.h>
  18 #if !defined (CONFIG_PANIC_HANG)
  19 #include <command.h>
  20 /*cmd_boot.c*/
  21 extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
  22 #endif
  23
  24 #ifdef CONFIG_SYS_64BIT_VSPRINTF
  25 # define NUM_TYPE long long
  26 #else
  27 # define NUM_TYPE long
  28 #endif
  29 #define noinline __attribute__((noinline))
  30
  31 #define do_div(n, base) ({ \
  32         unsigned int __res; \
  33         __res = ((unsigned NUM_TYPE) n) % base; \
  34         n = ((unsigned NUM_TYPE) n) / base; \
  35         __res; \
  36 })
  37
  38 const char hex_asc[] = "0123456789abcdef";
  39 #define hex_asc_lo(x)   hex_asc[((x) & 0x0f)]
  40 #define hex_asc_hi(x)   hex_asc[((x) & 0xf0) >> 4]
  41
  42 static inline char *pack_hex_byte(char *buf, u8 byte)
  43 {
  44         *buf++ = hex_asc_hi(byte);
  45         *buf++ = hex_asc_lo(byte);
  46         return buf;
  47 }
  48
  49 unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)
  50 {
  51         unsigned long result = 0,value;
  52
  53         if (*cp == '0') {
  54                 cp++;
  55                 if ((*cp == 'x') && isxdigit(cp[1])) {
  56                         base = 16;
  57                         cp++;
  58                 }
  59                 if (!base) {
  60                         base = 8;
  61                 }
  62         }
  63         if (!base) {
  64                 base = 10;
  65         }
  66         while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
  67             ? toupper(*cp) : *cp)-'A'+10) < base) {
  68                 result = result*base + value;
  69                 cp++;
  70         }
  71         if (endp)
  72                 *endp = (char *)cp;
  73         return result;
  74 }
  75
  76 long simple_strtol(const char *cp,char **endp,unsigned int base)
  77 {
  78         if(*cp=='-')
  79                 return -simple_strtoul(cp+1,endp,base);
  80         return simple_strtoul(cp,endp,base);
  81 }
  82
  83 int ustrtoul(const char *cp, char **endp, unsigned int base)
  84 {
  85         unsigned long result = simple_strtoul(cp, endp, base);
  86         switch (**endp) {
  87         case 'G' :
  88                 result *= 1024;
  89                 /* fall through */
  90         case 'M':
  91                 result *= 1024;
  92                 /* fall through */
  93         case 'K':
  94         case 'k':
  95                 result *= 1024;
  96                 if ((*endp)[1] == 'i') {
  97                         if ((*endp)[2] == 'B')
  98                                 (*endp) += 3;
  99                         else
 100                                 (*endp) += 2;
 101                 }
 102         }
 103         return result;
 104 }
 105
 106 #ifdef CONFIG_SYS_64BIT_STRTOUL
 107 unsigned long long simple_strtoull (const char *cp, char **endp, unsigned int base)
 108 {
 109         unsigned long long result = 0, value;
 110
 111         if (*cp == '0') {
 112                 cp++;
 113                 if ((*cp == 'x') && isxdigit (cp[1])) {
 114                         base = 16;
 115                         cp++;
 116                 }
 117                 if (!base) {
 118                         base = 8;
 119                 }
 120         }
 121         if (!base) {
 122                 base = 10;
 123         }
 124         while (isxdigit (*cp) && (value = isdigit (*cp)
 125                                 ? *cp - '0'
 126                                 : (islower (*cp) ? toupper (*cp) : *cp) - 'A' + 10) < base) {
 127                 result = result * base + value;
 128                 cp++;
 129         }
 130         if (endp)
 131                 *endp = (char *) cp;
 132         return result;
 133 }
 134 #endif /* CONFIG_SYS_64BIT_STRTOUL */
 135
 136 /* we use this so that we can do without the ctype library */
 137 #define is_digit(c)     ((c) >= '0' && (c) <= '9')
 138
 139 static int skip_atoi(const char **s)
 140 {
 141         int i=0;
 142
 143         while (is_digit(**s))
 144                 i = i*10 + *((*s)++) - '0';
 145         return i;
 146 }
 147
 148 /* Decimal conversion is by far the most typical, and is used
 149  * for /proc and /sys data. This directly impacts e.g. top performance
 150  * with many processes running. We optimize it for speed
 151  * using code from
 152  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 153  * (with permission from the author, Douglas W. Jones). */
 154
 155 /* Formats correctly any integer in [0,99999].
 156  * Outputs from one to five digits depending on input.
 157  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
 158 static char* put_dec_trunc(char *buf, unsigned q)
 159 {
 160         unsigned d3, d2, d1, d0;
 161         d1 = (q>>4) & 0xf;
 162         d2 = (q>>8) & 0xf;
 163         d3 = (q>>12);
 164
 165         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 166         q = (d0 * 0xcd) >> 11;
 167         d0 = d0 - 10*q;
 168         *buf++ = d0 + '0'; /* least significant digit */
 169         d1 = q + 9*d3 + 5*d2 + d1;
 170         if (d1 != 0) {
 171                 q = (d1 * 0xcd) >> 11;
 172                 d1 = d1 - 10*q;
 173                 *buf++ = d1 + '0'; /* next digit */
 174
 175                 d2 = q + 2*d2;
 176                 if ((d2 != 0) || (d3 != 0)) {
 177                         q = (d2 * 0xd) >> 7;
 178                         d2 = d2 - 10*q;
 179                         *buf++ = d2 + '0'; /* next digit */
 180
 181                         d3 = q + 4*d3;
 182                         if (d3 != 0) {
 183                                 q = (d3 * 0xcd) >> 11;
 184                                 d3 = d3 - 10*q;
 185                                 *buf++ = d3 + '0';  /* next digit */
 186                                 if (q != 0)
 187                                         *buf++ = q + '0';  /* most sign. digit */
 188                         }
 189                 }
 190         }
 191         return buf;
 192 }
 193 /* Same with if's removed. Always emits five digits */
 194 static char* put_dec_full(char *buf, unsigned q)
 195 {
 196         /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
 197         /* but anyway, gcc produces better code with full-sized ints */
 198         unsigned d3, d2, d1, d0;
 199         d1 = (q>>4) & 0xf;
 200         d2 = (q>>8) & 0xf;
 201         d3 = (q>>12);
 202
 203         /*
 204          * Possible ways to approx. divide by 10
 205          * gcc -O2 replaces multiply with shifts and adds
 206          * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
 207          * (x * 0x67) >> 10:  1100111
 208          * (x * 0x34) >> 9:    110100 - same
 209          * (x * 0x1a) >> 8:     11010 - same
 210          * (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
 211          */
 212
 213         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 214         q = (d0 * 0xcd) >> 11;
 215         d0 = d0 - 10*q;
 216         *buf++ = d0 + '0';
 217         d1 = q + 9*d3 + 5*d2 + d1;
 218                 q = (d1 * 0xcd) >> 11;
 219                 d1 = d1 - 10*q;
 220                 *buf++ = d1 + '0';
 221
 222                 d2 = q + 2*d2;
 223                         q = (d2 * 0xd) >> 7;
 224                         d2 = d2 - 10*q;
 225                         *buf++ = d2 + '0';
 226
 227                         d3 = q + 4*d3;
 228                                 q = (d3 * 0xcd) >> 11; /* - shorter code */
 229                                 /* q = (d3 * 0x67) >> 10; - would also work */
 230                                 d3 = d3 - 10*q;
 231                                 *buf++ = d3 + '0';
 232                                         *buf++ = q + '0';
 233         return buf;
 234 }
 235 /* No inlining helps gcc to use registers better */
 236 static noinline char* put_dec(char *buf, unsigned NUM_TYPE num)
 237 {
 238         while (1) {
 239                 unsigned rem;
 240                 if (num < 100000)
 241                         return put_dec_trunc(buf, num);
 242                 rem = do_div(num, 100000);
 243                 buf = put_dec_full(buf, rem);
 244         }
 245 }
 246
 247 #define ZEROPAD 1               /* pad with zero */
 248 #define SIGN    2               /* unsigned/signed long */
 249 #define PLUS    4               /* show plus */
 250 #define SPACE   8               /* space if plus */
 251 #define LEFT    16              /* left justified */
 252 #define SMALL   32              /* Must be 32 == 0x20 */
 253 #define SPECIAL 64              /* 0x */
 254
 255 static char *number(char *buf, unsigned NUM_TYPE num, int base, int size, int precision, int type)
 256 {
 257         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 258         static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
 259
 260         char tmp[66];
 261         char sign;
 262         char locase;
 263         int need_pfx = ((type & SPECIAL) && base != 10);
 264         int i;
 265
 266         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 267          * produces same digits or (maybe lowercased) letters */
 268         locase = (type & SMALL);
 269         if (type & LEFT)
 270                 type &= ~ZEROPAD;
 271         sign = 0;
 272         if (type & SIGN) {
 273                 if ((signed NUM_TYPE) num < 0) {
 274                         sign = '-';
 275                         num = - (signed NUM_TYPE) num;
 276                         size--;
 277                 } else if (type & PLUS) {
 278                         sign = '+';
 279                         size--;
 280                 } else if (type & SPACE) {
 281                         sign = ' ';
 282                         size--;
 283                 }
 284         }
 285         if (need_pfx) {
 286                 size--;
 287                 if (base == 16)
 288                         size--;
 289         }
 290
 291         /* generate full string in tmp[], in reverse order */
 292         i = 0;
 293         if (num == 0)
 294                 tmp[i++] = '0';
 295         /* Generic code, for any base:
 296         else do {
 297                 tmp[i++] = (digits[do_div(num,base)] | locase);
 298         } while (num != 0);
 299         */
 300         else if (base != 10) { /* 8 or 16 */
 301                 int mask = base - 1;
 302                 int shift = 3;
 303                 if (base == 16) shift = 4;
 304                 do {
 305                         tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 306                         num >>= shift;
 307                 } while (num);
 308         } else { /* base 10 */
 309                 i = put_dec(tmp, num) - tmp;
 310         }
 311
 312         /* printing 100 using %2d gives "100", not "00" */
 313         if (i > precision)
 314                 precision = i;
 315         /* leading space padding */
 316         size -= precision;
 317         if (!(type & (ZEROPAD+LEFT)))
 318                 while(--size >= 0)
 319                         *buf++ = ' ';
 320         /* sign */
 321         if (sign)
 322                 *buf++ = sign;
 323         /* "0x" / "0" prefix */
 324         if (need_pfx) {
 325                 *buf++ = '0';
 326                 if (base == 16)
 327                         *buf++ = ('X' | locase);
 328         }
 329         /* zero or space padding */
 330         if (!(type & LEFT)) {
 331                 char c = (type & ZEROPAD) ? '0' : ' ';
 332                 while (--size >= 0)
 333                         *buf++ = c;
 334         }
 335         /* hmm even more zero padding? */
 336         while (i <= --precision)
 337                 *buf++ = '0';
 338         /* actual digits of result */
 339         while (--i >= 0)
 340                 *buf++ = tmp[i];
 341         /* trailing space padding */
 342         while (--size >= 0)
 343                 *buf++ = ' ';
 344         return buf;
 345 }
 346
 347 static char *string(char *buf, char *s, int field_width, int precision, int flags)
 348 {
 349         int len, i;
 350
 351         if (s == 0)
 352                 s = "<NULL>";
 353
 354         len = strnlen(s, precision);
 355
 356         if (!(flags & LEFT))
 357                 while (len < field_width--)
 358                         *buf++ = ' ';
 359         for (i = 0; i < len; ++i)
 360                 *buf++ = *s++;
 361         while (len < field_width--)
 362                 *buf++ = ' ';
 363         return buf;
 364 }
 365
 366 #ifdef CONFIG_CMD_NET
 367 static char *mac_address_string(char *buf, u8 *addr, int field_width,
 368                                 int precision, int flags)
 369 {
 370         char mac_addr[6 * 3]; /* (6 * 2 hex digits), 5 colons and trailing zero */
 371         char *p = mac_addr;
 372         int i;
 373
 374         for (i = 0; i < 6; i++) {
 375                 p = pack_hex_byte(p, addr[i]);
 376                 if (!(flags & SPECIAL) && i != 5)
 377                         *p++ = ':';
 378         }
 379         *p = '\0';
 380
 381         return string(buf, mac_addr, field_width, precision, flags & ~SPECIAL);
 382 }
 383
 384 static char *ip6_addr_string(char *buf, u8 *addr, int field_width,
 385                          int precision, int flags)
 386 {
 387         char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */
 388         char *p = ip6_addr;
 389         int i;
 390
 391         for (i = 0; i < 8; i++) {
 392                 p = pack_hex_byte(p, addr[2 * i]);
 393                 p = pack_hex_byte(p, addr[2 * i + 1]);
 394                 if (!(flags & SPECIAL) && i != 7)
 395                         *p++ = ':';
 396         }
 397         *p = '\0';
 398
 399         return string(buf, ip6_addr, field_width, precision, flags & ~SPECIAL);
 400 }
 401
 402 static char *ip4_addr_string(char *buf, u8 *addr, int field_width,
 403                          int precision, int flags)
 404 {
 405         char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */
 406         char temp[3];   /* hold each IP quad in reverse order */
 407         char *p = ip4_addr;
 408         int i, digits;
 409
 410         for (i = 0; i < 4; i++) {
 411                 digits = put_dec_trunc(temp, addr[i]) - temp;
 412                 /* reverse the digits in the quad */
 413                 while (digits--)
 414                         *p++ = temp[digits];
 415                 if (i != 3)
 416                         *p++ = '.';
 417         }
 418         *p = '\0';
 419
 420         return string(buf, ip4_addr, field_width, precision, flags & ~SPECIAL);
 421 }
 422 #endif
 423
 424 /*
 425  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 426  * by an extra set of alphanumeric characters that are extended format
 427  * specifiers.
 428  *
 429  * Right now we handle:
 430  *
 431  * - 'M' For a 6-byte MAC address, it prints the address in the
 432  *       usual colon-separated hex notation
 433  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated
 434  *       decimal for v4 and colon separated network-order 16 bit hex for v6)
 435  * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
 436  *       currently the same
 437  *
 438  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 439  * function pointers are really function descriptors, which contain a
 440  * pointer to the real address.
 441  */
 442 static char *pointer(const char *fmt, char *buf, void *ptr, int field_width, int precision, int flags)
 443 {
 444         if (!ptr)
 445                 return string(buf, "(null)", field_width, precision, flags);
 446
 447 #ifdef CONFIG_CMD_NET
 448         switch (*fmt) {
 449         case 'm':
 450                 flags |= SPECIAL;
 451                 /* Fallthrough */
 452         case 'M':
 453                 return mac_address_string(buf, ptr, field_width, precision, flags);
 454         case 'i':
 455                 flags |= SPECIAL;
 456                 /* Fallthrough */
 457         case 'I':
 458                 if (fmt[1] == '6')
 459                         return ip6_addr_string(buf, ptr, field_width, precision, flags);
 460                 if (fmt[1] == '4')
 461                         return ip4_addr_string(buf, ptr, field_width, precision, flags);
 462                 flags &= ~SPECIAL;
 463                 break;
 464         }
 465 #endif
 466         flags |= SMALL;
 467         if (field_width == -1) {
 468                 field_width = 2*sizeof(void *);
 469                 flags |= ZEROPAD;
 470         }
 471         return number(buf, (unsigned long) ptr, 16, field_width, precision, flags);
 472 }
 473
 474 /**
 475  * vsprintf - Format a string and place it in a buffer
 476  * @buf: The buffer to place the result into
 477  * @fmt: The format string to use
 478  * @args: Arguments for the format string
 479  *
 480  * This function follows C99 vsprintf, but has some extensions:
 481  * %pS output the name of a text symbol
 482  * %pF output the name of a function pointer
 483  * %pR output the address range in a struct resource
 484  *
 485  * The function returns the number of characters written
 486  * into @buf.
 487  *
 488  * Call this function if you are already dealing with a va_list.
 489  * You probably want sprintf() instead.
 490  */
 491 int vsprintf(char *buf, const char *fmt, va_list args)
 492 {
 493         unsigned NUM_TYPE num;
 494         int base;
 495         char *str;
 496
 497         int flags;              /* flags to number() */
 498
 499         int field_width;        /* width of output field */
 500         int precision;          /* min. # of digits for integers; max
 501                                    number of chars for from string */
 502         int qualifier;          /* 'h', 'l', or 'L' for integer fields */
 503                                 /* 'z' support added 23/7/1999 S.H.    */
 504                                 /* 'z' changed to 'Z' --davidm 1/25/99 */
 505                                 /* 't' added for ptrdiff_t */
 506
 507         str = buf;
 508
 509         for (; *fmt ; ++fmt) {
 510                 if (*fmt != '%') {
 511                         *str++ = *fmt;
 512                         continue;
 513                 }
 514
 515                 /* process flags */
 516                 flags = 0;
 517                 repeat:
 518                         ++fmt;          /* this also skips first '%' */
 519                         switch (*fmt) {
 520                                 case '-': flags |= LEFT; goto repeat;
 521                                 case '+': flags |= PLUS; goto repeat;
 522                                 case ' ': flags |= SPACE; goto repeat;
 523                                 case '#': flags |= SPECIAL; goto repeat;
 524                                 case '0': flags |= ZEROPAD; goto repeat;
 525                         }
 526
 527                 /* get field width */
 528                 field_width = -1;
 529                 if (is_digit(*fmt))
 530                         field_width = skip_atoi(&fmt);
 531                 else if (*fmt == '*') {
 532                         ++fmt;
 533                         /* it's the next argument */
 534                         field_width = va_arg(args, int);
 535                         if (field_width < 0) {
 536                                 field_width = -field_width;
 537                                 flags |= LEFT;
 538                         }
 539                 }
 540
 541                 /* get the precision */
 542                 precision = -1;
 543                 if (*fmt == '.') {
 544                         ++fmt;
 545                         if (is_digit(*fmt))
 546                                 precision = skip_atoi(&fmt);
 547                         else if (*fmt == '*') {
 548                                 ++fmt;
 549                                 /* it's the next argument */
 550                                 precision = va_arg(args, int);
 551                         }
 552                         if (precision < 0)
 553                                 precision = 0;
 554                 }
 555
 556                 /* get the conversion qualifier */
 557                 qualifier = -1;
 558                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 559                     *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
 560                         qualifier = *fmt;
 561                         ++fmt;
 562                         if (qualifier == 'l' && *fmt == 'l') {
 563                                 qualifier = 'L';
 564                                 ++fmt;
 565                         }
 566                 }
 567
 568                 /* default base */
 569                 base = 10;
 570
 571                 switch (*fmt) {
 572                 case 'c':
 573                         if (!(flags & LEFT))
 574                                 while (--field_width > 0)
 575                                         *str++ = ' ';
 576                         *str++ = (unsigned char) va_arg(args, int);
 577                         while (--field_width > 0)
 578                                 *str++ = ' ';
 579                         continue;
 580
 581                 case 's':
 582                         str = string(str, va_arg(args, char *), field_width, precision, flags);
 583                         continue;
 584
 585                 case 'p':
 586                         str = pointer(fmt+1, str,
 587                                         va_arg(args, void *),
 588                                         field_width, precision, flags);
 589                         /* Skip all alphanumeric pointer suffixes */
 590                         while (isalnum(fmt[1]))
 591                                 fmt++;
 592                         continue;
 593
 594                 case 'n':
 595                         if (qualifier == 'l') {
 596                                 long * ip = va_arg(args, long *);
 597                                 *ip = (str - buf);
 598                         } else {
 599                                 int * ip = va_arg(args, int *);
 600                                 *ip = (str - buf);
 601                         }
 602                         continue;
 603
 604                 case '%':
 605                         *str++ = '%';
 606                         continue;
 607
 608                 /* integer number formats - set up the flags and "break" */
 609                 case 'o':
 610                         base = 8;
 611                         break;
 612
 613                 case 'x':
 614                         flags |= SMALL;
 615                 case 'X':
 616                         base = 16;
 617                         break;
 618
 619                 case 'd':
 620                 case 'i':
 621                         flags |= SIGN;
 622                 case 'u':
 623                         break;
 624
 625                 default:
 626                         *str++ = '%';
 627                         if (*fmt)
 628                                 *str++ = *fmt;
 629                         else
 630                                 --fmt;
 631                         continue;
 632                 }
 633 #ifdef CONFIG_SYS_64BIT_VSPRINTF
 634                 if (qualifier == 'L')  /* "quad" for 64 bit variables */
 635                         num = va_arg(args, unsigned long long);
 636                 else
 637 #endif
 638                 if (qualifier == 'l') {
 639                         num = va_arg(args, unsigned long);
 640                         if (flags & SIGN)
 641                                 num = (signed long) num;
 642                 } else if (qualifier == 'Z' || qualifier == 'z') {
 643                         num = va_arg(args, size_t);
 644                 } else if (qualifier == 't') {
 645                         num = va_arg(args, ptrdiff_t);
 646                 } else if (qualifier == 'h') {
 647                         num = (unsigned short) va_arg(args, int);
 648                         if (flags & SIGN)
 649                                 num = (signed short) num;
 650                 } else {
 651                         num = va_arg(args, unsigned int);
 652                         if (flags & SIGN)
 653                                 num = (signed int) num;
 654                 }
 655                 str = number(str, num, base, field_width, precision, flags);
 656         }
 657         *str = '\0';
 658         return str-buf;
 659 }
 660
 661 /**
 662  * sprintf - Format a string and place it in a buffer
 663  * @buf: The buffer to place the result into
 664  * @fmt: The format string to use
 665  * @...: Arguments for the format string
 666  *
 667  * The function returns the number of characters written
 668  * into @buf.
 669  *
 670  * See the vsprintf() documentation for format string extensions over C99.
 671  */
 672 int sprintf(char * buf, const char *fmt, ...)
 673 {
 674         va_list args;
 675         int i;
 676
 677         va_start(args, fmt);
 678         i=vsprintf(buf,fmt,args);
 679         va_end(args);
 680         return i;
 681 }
 682
 683 void panic(const char *fmt, ...)
 684 {
 685         va_list args;
 686         va_start(args, fmt);
 687         vprintf(fmt, args);
 688         putc('\n');
 689         va_end(args);
 690 #if defined (CONFIG_PANIC_HANG)
 691         hang();
 692 #else
 693         udelay (100000);        /* allow messages to go out */
 694         do_reset (NULL, 0, 0, NULL);
 695 #endif
 696 }