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  * from hush: simple_itoa() was lifted from boa-0.93.15
  12  */
  13
  14 #include <stdarg.h>
  15 #include <linux/types.h>
  16 #include <linux/string.h>
  17 #include <linux/ctype.h>
  18 #include <errno.h>
  19
  20 #include <common.h>
  21 #if !defined(CONFIG_PANIC_HANG)
  22 #include <command.h>
  23 #endif
  24
  25 #include <div64.h>
  26 #define noinline __attribute__((noinline))
  27
  28 /* some reluctance to put this into a new limits.h, so it is here */
  29 #define INT_MAX         ((int)(~0U>>1))
  30
  31 const char hex_asc[] = "0123456789abcdef";
  32 #define hex_asc_lo(x)   hex_asc[((x) & 0x0f)]
  33 #define hex_asc_hi(x)   hex_asc[((x) & 0xf0) >> 4]
  34
  35 static inline char *pack_hex_byte(char *buf, u8 byte)
  36 {
  37         *buf++ = hex_asc_hi(byte);
  38         *buf++ = hex_asc_lo(byte);
  39         return buf;
  40 }
  41
  42 unsigned long simple_strtoul(const char *cp, char **endp,
  43                                 unsigned int base)
  44 {
  45         unsigned long result = 0;
  46         unsigned long value;
  47
  48         if (*cp == '0') {
  49                 cp++;
  50                 if ((*cp == 'x') && isxdigit(cp[1])) {
  51                         base = 16;
  52                         cp++;
  53                 }
  54
  55                 if (!base)
  56                         base = 8;
  57         }
  58
  59         if (!base)
  60                 base = 10;
  61
  62         while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
  63             ? toupper(*cp) : *cp)-'A'+10) < base) {
  64                 result = result*base + value;
  65                 cp++;
  66         }
  67
  68         if (endp)
  69                 *endp = (char *)cp;
  70
  71         return result;
  72 }
  73
  74 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
  75 {
  76         char *tail;
  77         unsigned long val;
  78         size_t len;
  79
  80         *res = 0;
  81         len = strlen(cp);
  82         if (len == 0)
  83                 return -EINVAL;
  84
  85         val = simple_strtoul(cp, &tail, base);
  86         if (tail == cp)
  87                 return -EINVAL;
  88
  89         if ((*tail == '\0') ||
  90                 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
  91                 *res = val;
  92                 return 0;
  93         }
  94
  95         return -EINVAL;
  96 }
  97
  98 long simple_strtol(const char *cp, char **endp, unsigned int base)
  99 {
 100         if (*cp == '-')
 101                 return -simple_strtoul(cp + 1, endp, base);
 102
 103         return simple_strtoul(cp, endp, base);
 104 }
 105
 106 int ustrtoul(const char *cp, char **endp, unsigned int base)
 107 {
 108         unsigned long result = simple_strtoul(cp, endp, base);
 109         switch (**endp) {
 110         case 'G':
 111                 result *= 1024;
 112                 /* fall through */
 113         case 'M':
 114                 result *= 1024;
 115                 /* fall through */
 116         case 'K':
 117         case 'k':
 118                 result *= 1024;
 119                 if ((*endp)[1] == 'i') {
 120                         if ((*endp)[2] == 'B')
 121                                 (*endp) += 3;
 122                         else
 123                                 (*endp) += 2;
 124                 }
 125         }
 126         return result;
 127 }
 128
 129 unsigned long long simple_strtoull(const char *cp, char **endp,
 130                                         unsigned int base)
 131 {
 132         unsigned long long result = 0, value;
 133
 134         if (*cp == '0') {
 135                 cp++;
 136                 if ((*cp == 'x') && isxdigit(cp[1])) {
 137                         base = 16;
 138                         cp++;
 139                 }
 140
 141                 if (!base)
 142                         base = 8;
 143         }
 144
 145         if (!base)
 146                 base = 10;
 147
 148         while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp - '0'
 149                 : (islower(*cp) ? toupper(*cp) : *cp) - 'A' + 10) < base) {
 150                 result = result * base + value;
 151                 cp++;
 152         }
 153
 154         if (endp)
 155                 *endp = (char *) cp;
 156
 157         return result;
 158 }
 159
 160 /* we use this so that we can do without the ctype library */
 161 #define is_digit(c)     ((c) >= '0' && (c) <= '9')
 162
 163 static int skip_atoi(const char **s)
 164 {
 165         int i = 0;
 166
 167         while (is_digit(**s))
 168                 i = i * 10 + *((*s)++) - '0';
 169
 170         return i;
 171 }
 172
 173 /* Decimal conversion is by far the most typical, and is used
 174  * for /proc and /sys data. This directly impacts e.g. top performance
 175  * with many processes running. We optimize it for speed
 176  * using code from
 177  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
 178  * (with permission from the author, Douglas W. Jones). */
 179
 180 /* Formats correctly any integer in [0,99999].
 181  * Outputs from one to five digits depending on input.
 182  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
 183 static char *put_dec_trunc(char *buf, unsigned q)
 184 {
 185         unsigned d3, d2, d1, d0;
 186         d1 = (q>>4) & 0xf;
 187         d2 = (q>>8) & 0xf;
 188         d3 = (q>>12);
 189
 190         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 191         q = (d0 * 0xcd) >> 11;
 192         d0 = d0 - 10*q;
 193         *buf++ = d0 + '0'; /* least significant digit */
 194         d1 = q + 9*d3 + 5*d2 + d1;
 195         if (d1 != 0) {
 196                 q = (d1 * 0xcd) >> 11;
 197                 d1 = d1 - 10*q;
 198                 *buf++ = d1 + '0'; /* next digit */
 199
 200                 d2 = q + 2*d2;
 201                 if ((d2 != 0) || (d3 != 0)) {
 202                         q = (d2 * 0xd) >> 7;
 203                         d2 = d2 - 10*q;
 204                         *buf++ = d2 + '0'; /* next digit */
 205
 206                         d3 = q + 4*d3;
 207                         if (d3 != 0) {
 208                                 q = (d3 * 0xcd) >> 11;
 209                                 d3 = d3 - 10*q;
 210                                 *buf++ = d3 + '0';  /* next digit */
 211                                 if (q != 0)
 212                                         *buf++ = q + '0'; /* most sign. digit */
 213                         }
 214                 }
 215         }
 216         return buf;
 217 }
 218 /* Same with if's removed. Always emits five digits */
 219 static char *put_dec_full(char *buf, unsigned q)
 220 {
 221         /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
 222         /* but anyway, gcc produces better code with full-sized ints */
 223         unsigned d3, d2, d1, d0;
 224         d1 = (q>>4) & 0xf;
 225         d2 = (q>>8) & 0xf;
 226         d3 = (q>>12);
 227
 228         /*
 229          * Possible ways to approx. divide by 10
 230          * gcc -O2 replaces multiply with shifts and adds
 231          * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
 232          * (x * 0x67) >> 10:  1100111
 233          * (x * 0x34) >> 9:    110100 - same
 234          * (x * 0x1a) >> 8:     11010 - same
 235          * (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
 236          */
 237
 238         d0 = 6*(d3 + d2 + d1) + (q & 0xf);
 239         q = (d0 * 0xcd) >> 11;
 240         d0 = d0 - 10*q;
 241         *buf++ = d0 + '0';
 242         d1 = q + 9*d3 + 5*d2 + d1;
 243                 q = (d1 * 0xcd) >> 11;
 244                 d1 = d1 - 10*q;
 245                 *buf++ = d1 + '0';
 246
 247                 d2 = q + 2*d2;
 248                         q = (d2 * 0xd) >> 7;
 249                         d2 = d2 - 10*q;
 250                         *buf++ = d2 + '0';
 251
 252                         d3 = q + 4*d3;
 253                                 q = (d3 * 0xcd) >> 11; /* - shorter code */
 254                                 /* q = (d3 * 0x67) >> 10; - would also work */
 255                                 d3 = d3 - 10*q;
 256                                 *buf++ = d3 + '0';
 257                                         *buf++ = q + '0';
 258         return buf;
 259 }
 260 /* No inlining helps gcc to use registers better */
 261 static noinline char *put_dec(char *buf, u64 num)
 262 {
 263         while (1) {
 264                 unsigned rem;
 265                 if (num < 100000)
 266                         return put_dec_trunc(buf, num);
 267                 rem = do_div(num, 100000);
 268                 buf = put_dec_full(buf, rem);
 269         }
 270 }
 271
 272 #define ZEROPAD 1               /* pad with zero */
 273 #define SIGN    2               /* unsigned/signed long */
 274 #define PLUS    4               /* show plus */
 275 #define SPACE   8               /* space if plus */
 276 #define LEFT    16              /* left justified */
 277 #define SMALL   32              /* Must be 32 == 0x20 */
 278 #define SPECIAL 64              /* 0x */
 279
 280 #ifdef CONFIG_SYS_VSNPRINTF
 281 /*
 282  * Macro to add a new character to our output string, but only if it will
 283  * fit. The macro moves to the next character position in the output string.
 284  */
 285 #define ADDCH(str, ch) do { \
 286         if ((str) < end) \
 287                 *(str) = (ch); \
 288         ++str; \
 289         } while (0)
 290 #else
 291 #define ADDCH(str, ch)  (*(str)++ = (ch))
 292 #endif
 293
 294 static char *number(char *buf, char *end, u64 num,
 295                 int base, int size, int precision, int type)
 296 {
 297         /* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 298         static const char digits[16] = "0123456789ABCDEF";
 299
 300         char tmp[66];
 301         char sign;
 302         char locase;
 303         int need_pfx = ((type & SPECIAL) && base != 10);
 304         int i;
 305
 306         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 307          * produces same digits or (maybe lowercased) letters */
 308         locase = (type & SMALL);
 309         if (type & LEFT)
 310                 type &= ~ZEROPAD;
 311         sign = 0;
 312         if (type & SIGN) {
 313                 if ((s64) num < 0) {
 314                         sign = '-';
 315                         num = -(s64) num;
 316                         size--;
 317                 } else if (type & PLUS) {
 318                         sign = '+';
 319                         size--;
 320                 } else if (type & SPACE) {
 321                         sign = ' ';
 322                         size--;
 323                 }
 324         }
 325         if (need_pfx) {
 326                 size--;
 327                 if (base == 16)
 328                         size--;
 329         }
 330
 331         /* generate full string in tmp[], in reverse order */
 332         i = 0;
 333         if (num == 0)
 334                 tmp[i++] = '0';
 335         /* Generic code, for any base:
 336         else do {
 337                 tmp[i++] = (digits[do_div(num,base)] | locase);
 338         } while (num != 0);
 339         */
 340         else if (base != 10) { /* 8 or 16 */
 341                 int mask = base - 1;
 342                 int shift = 3;
 343
 344                 if (base == 16)
 345                         shift = 4;
 346
 347                 do {
 348                         tmp[i++] = (digits[((unsigned char)num) & mask]
 349                                         | locase);
 350                         num >>= shift;
 351                 } while (num);
 352         } else { /* base 10 */
 353                 i = put_dec(tmp, num) - tmp;
 354         }
 355
 356         /* printing 100 using %2d gives "100", not "00" */
 357         if (i > precision)
 358                 precision = i;
 359         /* leading space padding */
 360         size -= precision;
 361         if (!(type & (ZEROPAD + LEFT))) {
 362                 while (--size >= 0)
 363                         ADDCH(buf, ' ');
 364         }
 365         /* sign */
 366         if (sign)
 367                 ADDCH(buf, sign);
 368         /* "0x" / "0" prefix */
 369         if (need_pfx) {
 370                 ADDCH(buf, '0');
 371                 if (base == 16)
 372                         ADDCH(buf, 'X' | locase);
 373         }
 374         /* zero or space padding */
 375         if (!(type & LEFT)) {
 376                 char c = (type & ZEROPAD) ? '0' : ' ';
 377
 378                 while (--size >= 0)
 379                         ADDCH(buf, c);
 380         }
 381         /* hmm even more zero padding? */
 382         while (i <= --precision)
 383                 ADDCH(buf, '0');
 384         /* actual digits of result */
 385         while (--i >= 0)
 386                 ADDCH(buf, tmp[i]);
 387         /* trailing space padding */
 388         while (--size >= 0)
 389                 ADDCH(buf, ' ');
 390         return buf;
 391 }
 392
 393 static char *string(char *buf, char *end, char *s, int field_width,
 394                 int precision, int flags)
 395 {
 396         int len, i;
 397
 398         if (s == 0)
 399                 s = "<NULL>";
 400
 401         len = strnlen(s, precision);
 402
 403         if (!(flags & LEFT))
 404                 while (len < field_width--)
 405                         ADDCH(buf, ' ');
 406         for (i = 0; i < len; ++i)
 407                 ADDCH(buf, *s++);
 408         while (len < field_width--)
 409                 ADDCH(buf, ' ');
 410         return buf;
 411 }
 412
 413 #ifdef CONFIG_CMD_NET
 414 static char *mac_address_string(char *buf, char *end, u8 *addr, int field_width,
 415                                 int precision, int flags)
 416 {
 417         /* (6 * 2 hex digits), 5 colons and trailing zero */
 418         char mac_addr[6 * 3];
 419         char *p = mac_addr;
 420         int i;
 421
 422         for (i = 0; i < 6; i++) {
 423                 p = pack_hex_byte(p, addr[i]);
 424                 if (!(flags & SPECIAL) && i != 5)
 425                         *p++ = ':';
 426         }
 427         *p = '\0';
 428
 429         return string(buf, end, mac_addr, field_width, precision,
 430                       flags & ~SPECIAL);
 431 }
 432
 433 static char *ip6_addr_string(char *buf, char *end, u8 *addr, int field_width,
 434                          int precision, int flags)
 435 {
 436         /* (8 * 4 hex digits), 7 colons and trailing zero */
 437         char ip6_addr[8 * 5];
 438         char *p = ip6_addr;
 439         int i;
 440
 441         for (i = 0; i < 8; i++) {
 442                 p = pack_hex_byte(p, addr[2 * i]);
 443                 p = pack_hex_byte(p, addr[2 * i + 1]);
 444                 if (!(flags & SPECIAL) && i != 7)
 445                         *p++ = ':';
 446         }
 447         *p = '\0';
 448
 449         return string(buf, end, ip6_addr, field_width, precision,
 450                       flags & ~SPECIAL);
 451 }
 452
 453 static char *ip4_addr_string(char *buf, char *end, u8 *addr, int field_width,
 454                          int precision, int flags)
 455 {
 456         /* (4 * 3 decimal digits), 3 dots and trailing zero */
 457         char ip4_addr[4 * 4];
 458         char temp[3];   /* hold each IP quad in reverse order */
 459         char *p = ip4_addr;
 460         int i, digits;
 461
 462         for (i = 0; i < 4; i++) {
 463                 digits = put_dec_trunc(temp, addr[i]) - temp;
 464                 /* reverse the digits in the quad */
 465                 while (digits--)
 466                         *p++ = temp[digits];
 467                 if (i != 3)
 468                         *p++ = '.';
 469         }
 470         *p = '\0';
 471
 472         return string(buf, end, ip4_addr, field_width, precision,
 473                       flags & ~SPECIAL);
 474 }
 475 #endif
 476
 477 /*
 478  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 479  * by an extra set of alphanumeric characters that are extended format
 480  * specifiers.
 481  *
 482  * Right now we handle:
 483  *
 484  * - 'M' For a 6-byte MAC address, it prints the address in the
 485  *       usual colon-separated hex notation
 486  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated
 487  *       decimal for v4 and colon separated network-order 16 bit hex for v6)
 488  * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
 489  *       currently the same
 490  *
 491  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 492  * function pointers are really function descriptors, which contain a
 493  * pointer to the real address.
 494  */
 495 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 496                 int field_width, int precision, int flags)
 497 {
 498         if (!ptr)
 499                 return string(buf, end, "(null)", field_width, precision,
 500                               flags);
 501
 502 #ifdef CONFIG_CMD_NET
 503         switch (*fmt) {
 504         case 'm':
 505                 flags |= SPECIAL;
 506                 /* Fallthrough */
 507         case 'M':
 508                 return mac_address_string(buf, end, ptr, field_width,
 509                                           precision, flags);
 510         case 'i':
 511                 flags |= SPECIAL;
 512                 /* Fallthrough */
 513         case 'I':
 514                 if (fmt[1] == '6')
 515                         return ip6_addr_string(buf, end, ptr, field_width,
 516                                                precision, flags);
 517                 if (fmt[1] == '4')
 518                         return ip4_addr_string(buf, end, ptr, field_width,
 519                                                precision, flags);
 520                 flags &= ~SPECIAL;
 521                 break;
 522         }
 523 #endif
 524         flags |= SMALL;
 525         if (field_width == -1) {
 526                 field_width = 2*sizeof(void *);
 527                 flags |= ZEROPAD;
 528         }
 529         return number(buf, end, (unsigned long)ptr, 16, field_width,
 530                       precision, flags);
 531 }
 532
 533 static int vsnprintf_internal(char *buf, size_t size, const char *fmt,
 534                               va_list args)
 535 {
 536         u64 num;
 537         int base;
 538         char *str;
 539
 540         int flags;              /* flags to number() */
 541
 542         int field_width;        /* width of output field */
 543         int precision;          /* min. # of digits for integers; max
 544                                    number of chars for from string */
 545         int qualifier;          /* 'h', 'l', or 'L' for integer fields */
 546                                 /* 'z' support added 23/7/1999 S.H.    */
 547                                 /* 'z' changed to 'Z' --davidm 1/25/99 */
 548                                 /* 't' added for ptrdiff_t */
 549         char *end = buf + size;
 550
 551 #ifdef CONFIG_SYS_VSNPRINTF
 552         /* Make sure end is always >= buf - do we want this in U-Boot? */
 553         if (end < buf) {
 554                 end = ((void *)-1);
 555                 size = end - buf;
 556         }
 557 #endif
 558         str = buf;
 559
 560         for (; *fmt ; ++fmt) {
 561                 if (*fmt != '%') {
 562                         ADDCH(str, *fmt);
 563                         continue;
 564                 }
 565
 566                 /* process flags */
 567                 flags = 0;
 568 repeat:
 569                         ++fmt;          /* this also skips first '%' */
 570                         switch (*fmt) {
 571                         case '-':
 572                                 flags |= LEFT;
 573                                 goto repeat;
 574                         case '+':
 575                                 flags |= PLUS;
 576                                 goto repeat;
 577                         case ' ':
 578                                 flags |= SPACE;
 579                                 goto repeat;
 580                         case '#':
 581                                 flags |= SPECIAL;
 582                                 goto repeat;
 583                         case '0':
 584                                 flags |= ZEROPAD;
 585                                 goto repeat;
 586                         }
 587
 588                 /* get field width */
 589                 field_width = -1;
 590                 if (is_digit(*fmt))
 591                         field_width = skip_atoi(&fmt);
 592                 else if (*fmt == '*') {
 593                         ++fmt;
 594                         /* it's the next argument */
 595                         field_width = va_arg(args, int);
 596                         if (field_width < 0) {
 597                                 field_width = -field_width;
 598                                 flags |= LEFT;
 599                         }
 600                 }
 601
 602                 /* get the precision */
 603                 precision = -1;
 604                 if (*fmt == '.') {
 605                         ++fmt;
 606                         if (is_digit(*fmt))
 607                                 precision = skip_atoi(&fmt);
 608                         else if (*fmt == '*') {
 609                                 ++fmt;
 610                                 /* it's the next argument */
 611                                 precision = va_arg(args, int);
 612                         }
 613                         if (precision < 0)
 614                                 precision = 0;
 615                 }
 616
 617                 /* get the conversion qualifier */
 618                 qualifier = -1;
 619                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
 620                     *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
 621                         qualifier = *fmt;
 622                         ++fmt;
 623                         if (qualifier == 'l' && *fmt == 'l') {
 624                                 qualifier = 'L';
 625                                 ++fmt;
 626                         }
 627                 }
 628
 629                 /* default base */
 630                 base = 10;
 631
 632                 switch (*fmt) {
 633                 case 'c':
 634                         if (!(flags & LEFT)) {
 635                                 while (--field_width > 0)
 636                                         ADDCH(str, ' ');
 637                         }
 638                         ADDCH(str, (unsigned char) va_arg(args, int));
 639                         while (--field_width > 0)
 640                                 ADDCH(str, ' ');
 641                         continue;
 642
 643                 case 's':
 644                         str = string(str, end, va_arg(args, char *),
 645                                      field_width, precision, flags);
 646                         continue;
 647
 648                 case 'p':
 649                         str = pointer(fmt + 1, str, end,
 650                                         va_arg(args, void *),
 651                                         field_width, precision, flags);
 652                         /* Skip all alphanumeric pointer suffixes */
 653                         while (isalnum(fmt[1]))
 654                                 fmt++;
 655                         continue;
 656
 657                 case 'n':
 658                         if (qualifier == 'l') {
 659                                 long *ip = va_arg(args, long *);
 660                                 *ip = (str - buf);
 661                         } else {
 662                                 int *ip = va_arg(args, int *);
 663                                 *ip = (str - buf);
 664                         }
 665                         continue;
 666
 667                 case '%':
 668                         ADDCH(str, '%');
 669                         continue;
 670
 671                 /* integer number formats - set up the flags and "break" */
 672                 case 'o':
 673                         base = 8;
 674                         break;
 675
 676                 case 'x':
 677                         flags |= SMALL;
 678                 case 'X':
 679                         base = 16;
 680                         break;
 681
 682                 case 'd':
 683                 case 'i':
 684                         flags |= SIGN;
 685                 case 'u':
 686                         break;
 687
 688                 default:
 689                         ADDCH(str, '%');
 690                         if (*fmt)
 691                                 ADDCH(str, *fmt);
 692                         else
 693                                 --fmt;
 694                         continue;
 695                 }
 696                 if (qualifier == 'L')  /* "quad" for 64 bit variables */
 697                         num = va_arg(args, unsigned long long);
 698                 else if (qualifier == 'l') {
 699                         num = va_arg(args, unsigned long);
 700                         if (flags & SIGN)
 701                                 num = (signed long) num;
 702                 } else if (qualifier == 'Z' || qualifier == 'z') {
 703                         num = va_arg(args, size_t);
 704                 } else if (qualifier == 't') {
 705                         num = va_arg(args, ptrdiff_t);
 706                 } else if (qualifier == 'h') {
 707                         num = (unsigned short) va_arg(args, int);
 708                         if (flags & SIGN)
 709                                 num = (signed short) num;
 710                 } else {
 711                         num = va_arg(args, unsigned int);
 712                         if (flags & SIGN)
 713                                 num = (signed int) num;
 714                 }
 715                 str = number(str, end, num, base, field_width, precision,
 716                              flags);
 717         }
 718
 719 #ifdef CONFIG_SYS_VSNPRINTF
 720         if (size > 0) {
 721                 ADDCH(str, '\0');
 722                 if (str > end)
 723                         end[-1] = '\0';
 724         }
 725 #else
 726         *str = '\0';
 727 #endif
 728         /* the trailing null byte doesn't count towards the total */
 729         return str - buf;
 730 }
 731
 732 #ifdef CONFIG_SYS_VSNPRINTF
 733 int vsnprintf(char *buf, size_t size, const char *fmt,
 734                               va_list args)
 735 {
 736         return vsnprintf_internal(buf, size, fmt, args);
 737 }
 738
 739 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 740 {
 741         int i;
 742
 743         i = vsnprintf(buf, size, fmt, args);
 744
 745         if (likely(i < size))
 746                 return i;
 747         if (size != 0)
 748                 return size - 1;
 749         return 0;
 750 }
 751
 752 int snprintf(char *buf, size_t size, const char *fmt, ...)
 753 {
 754         va_list args;
 755         int i;
 756
 757         va_start(args, fmt);
 758         i = vsnprintf(buf, size, fmt, args);
 759         va_end(args);
 760
 761         return i;
 762 }
 763
 764 int scnprintf(char *buf, size_t size, const char *fmt, ...)
 765 {
 766         va_list args;
 767         int i;
 768
 769         va_start(args, fmt);
 770         i = vscnprintf(buf, size, fmt, args);
 771         va_end(args);
 772
 773         return i;
 774 }
 775 #endif /* CONFIG_SYS_VSNPRINT */
 776
 777 /**
 778  * Format a string and place it in a buffer (va_list version)
 779  *
 780  * @param buf   The buffer to place the result into
 781  * @param fmt   The format string to use
 782  * @param args  Arguments for the format string
 783  *
 784  * The function returns the number of characters written
 785  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
 786  * buffer overflows.
 787  *
 788  * If you're not already dealing with a va_list consider using sprintf().
 789  */
 790 int vsprintf(char *buf, const char *fmt, va_list args)
 791 {
 792         return vsnprintf_internal(buf, INT_MAX, fmt, args);
 793 }
 794
 795 int sprintf(char *buf, const char *fmt, ...)
 796 {
 797         va_list args;
 798         int i;
 799
 800         va_start(args, fmt);
 801         i = vsprintf(buf, fmt, args);
 802         va_end(args);
 803         return i;
 804 }
 805
 806 void panic(const char *fmt, ...)
 807 {
 808         va_list args;
 809         va_start(args, fmt);
 810         vprintf(fmt, args);
 811         putc('\n');
 812         va_end(args);
 813 #if defined(CONFIG_PANIC_HANG)
 814         hang();
 815 #else
 816         udelay(100000); /* allow messages to go out */
 817         do_reset(NULL, 0, 0, NULL);
 818 #endif
 819         while (1)
 820                 ;
 821 }
 822
 823 void __assert_fail(const char *assertion, const char *file, unsigned line,
 824                    const char *function)
 825 {
 826         /* This will not return */
 827         panic("%s:%u: %s: Assertion `%s' failed.", file, line, function,
 828               assertion);
 829 }
 830
 831 char *simple_itoa(ulong i)
 832 {
 833         /* 21 digits plus null terminator, good for 64-bit or smaller ints */
 834         static char local[22];
 835         char *p = &local[21];
 836
 837         *p-- = '\0';
 838         do {
 839                 *p-- = '0' + i % 10;
 840                 i /= 10;
 841         } while (i > 0);
 842         return p + 1;
 843 }