lib/ntdll/stdio/sprintf.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            lib/ntdll/stdio/sprintf.c
   6  * PURPOSE:         Single byte sprintf functions
   7  * PROGRAMMERS:     David Welch
   8  *                  Eric Kohl
   9  *
  10  */
  11
  12 /*
  13  *  linux/lib/vsprintf.c
  14  *
  15  *  Copyright (C) 1991, 1992  Linus Torvalds
  16  */
  17
  18 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
  19 /*
  20  * Wirzenius wrote this portably, Torvalds fucked it up :-)
  21  */
  22
  23 #include <ddk/ntddk.h>
  24 #include <stdarg.h>
  25 #include <stdlib.h>
  26 #include <ctype.h>
  27 #include <string.h>
  28 #include <limits.h>
  29
  30 #define NDEBUG
  31 #include <ntdll/ntdll.h>
  32
  33
  34 #define ZEROPAD 1               /* pad with zero */
  35 #define SIGN    2               /* unsigned/signed long */
  36 #define PLUS    4               /* show plus */
  37 #define SPACE   8               /* space if plus */
  38 #define LEFT    16              /* left justified */
  39 #define SPECIAL 32              /* 0x */
  40 #define LARGE   64              /* use 'ABCDEF' instead of 'abcdef' */
  41
  42
  43 #define do_div(n,base) ({ \
  44 int __res; \
  45 __res = ((unsigned long long) n) % (unsigned) base; \
  46 n = ((unsigned long long) n) / (unsigned) base; \
  47 __res; })
  48
  49
  50 static int skip_atoi(const char **s)
  51 {
  52         int i=0;
  53
  54         while (isdigit(**s))
  55                 i = i*10 + *((*s)++) - '0';
  56         return i;
  57 }
  58
  59
  60 static char *
  61 number(char * buf, char * end, long long num, int base, int size, int precision, int type)
  62 {
  63         char c,sign,tmp[66];
  64         const char *digits;
  65         const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
  66         const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  67         int i;
  68
  69         digits = (type & LARGE) ? large_digits : small_digits;
  70         if (type & LEFT)
  71                 type &= ~ZEROPAD;
  72         if (base < 2 || base > 36)
  73                 return 0;
  74         c = (type & ZEROPAD) ? '0' : ' ';
  75         sign = 0;
  76         if (type & SIGN) {
  77                 if (num < 0) {
  78                         sign = '-';
  79                         num = -num;
  80                         size--;
  81                 } else if (type & PLUS) {
  82                         sign = '+';
  83                         size--;
  84                 } else if (type & SPACE) {
  85                         sign = ' ';
  86                         size--;
  87                 }
  88         }
  89         if (type & SPECIAL) {
  90                 if (base == 16)
  91                         size -= 2;
  92                 else if (base == 8)
  93                         size--;
  94         }
  95         i = 0;
  96         if (num == 0)
  97                 tmp[i++]='0';
  98         else while (num != 0)
  99                 tmp[i++] = digits[do_div(num,base)];
 100         if (i > precision)
 101                 precision = i;
 102         size -= precision;
 103         if (!(type&(ZEROPAD+LEFT))) {
 104                 while(size-->0) {
 105                         if (buf <= end)
 106                                 *buf = ' ';
 107                         ++buf;
 108                 }
 109         }
 110         if (sign) {
 111                 if (buf <= end)
 112                         *buf = sign;
 113                 ++buf;
 114         }
 115         if (type & SPECIAL) {
 116                 if (base==8) {
 117                         if (buf <= end)
 118                                 *buf = '0';
 119                         ++buf;
 120                 } else if (base==16) {
 121                         if (buf <= end)
 122                                 *buf = '0';
 123                         ++buf;
 124                         if (buf <= end)
 125                                 *buf = digits[33];
 126                         ++buf;
 127                 }
 128         }
 129         if (!(type & LEFT)) {
 130                 while (size-- > 0) {
 131                         if (buf <= end)
 132                                 *buf = c;
 133                         ++buf;
 134                 }
 135         }
 136         while (i < precision--) {
 137                 if (buf <= end)
 138                         *buf = '0';
 139                 ++buf;
 140         }
 141         while (i-- > 0) {
 142                 if (buf <= end)
 143                         *buf = tmp[i];
 144                 ++buf;
 145         }
 146         while (size-- > 0) {
 147                 if (buf <= end)
 148                         *buf = ' ';
 149                 ++buf;
 150         }
 151         return buf;
 152 }
 153
 154 static char*
 155 string(char* buf, char* end, const char* s, int len, int field_width, int precision, int flags)
 156 {
 157         int i;
 158         if (s == NULL)
 159         {
 160                 s = "<NULL>";
 161                 len = 6;
 162         }
 163         else
 164         {
 165                 if (len == -1)
 166                 {
 167                         len = 0;
 168                         while (s[len] && (unsigned int)len < (unsigned int)precision)
 169                                 len++;
 170                 }
 171                 else
 172                 {
 173                         if ((unsigned int)len > (unsigned int)precision)
 174                                 len = precision;
 175                 }
 176         }
 177         if (!(flags & LEFT))
 178                 while (len < field_width--)
 179                 {
 180                         if (buf <= end)
 181                                 *buf = ' ';
 182                         ++buf;
 183                 }
 184         for (i = 0; i < len; ++i)
 185         {
 186                 if (buf <= end)
 187                         *buf = *s++;
 188                 ++buf;
 189         }
 190         while (len < field_width--)
 191         {
 192                 if (buf <= end)
 193                         *buf = ' ';
 194                 ++buf;
 195         }
 196         return buf;
 197 }
 198
 199 static char*
 200 stringw(char* buf, char* end, const wchar_t* sw, int len, int field_width, int precision, int flags)
 201 {
 202         int i;
 203         if (sw == NULL)
 204         {
 205                 sw = L"<NULL>";
 206                 len = 6;
 207         }
 208         else
 209         {
 210                 if (len == -1)
 211                 {
 212                         len = 0;
 213                         while (sw[len] && (unsigned int)len < (unsigned int)precision)
 214                                 len++;
 215                 }
 216                 else
 217                 {
 218                         if ((unsigned int)len > (unsigned int)precision)
 219                                 len = precision;
 220                 }
 221         }
 222         if (!(flags & LEFT))
 223                 while (len < field_width--)
 224                 {
 225                         if (buf <= end)
 226                                 *buf = ' ';
 227                         ++buf;
 228                 }
 229         for (i = 0; i < len; ++i)
 230         {
 231                 if (buf <= end)
 232                         *buf = (unsigned char)(*sw++);
 233                 ++buf;
 234         }
 235         while (len < field_width--)
 236         {
 237                 if (buf <= end)
 238                         *buf = ' ';
 239                 ++buf;
 240         }
 241         return buf;
 242 }
 243
 244 int _vsnprintf(char *buf, size_t cnt, const char *fmt, va_list args)
 245 {
 246         int len;
 247         unsigned long long num;
 248         int i, base;
 249         char *str, *end;
 250         const char *s;
 251         const wchar_t *sw;
 252
 253         int flags;              /* flags to number() */
 254
 255         int field_width;        /* width of output field */
 256         int precision;          /* min. # of digits for integers; max
 257                                    number of chars for from string */
 258         int qualifier;          /* 'h', 'l', 'L', 'I' or 'w' for integer fields */
 259
 260         str = buf;
 261         end = buf + cnt - 1;
 262         if (end < buf - 1) {
 263                 end = ((void *) -1);
 264                 cnt = end - buf + 1;
 265         }
 266
 267         for ( ; *fmt ; ++fmt) {
 268                 if (*fmt != '%') {
 269                         if (str <= end)
 270                                 *str = *fmt;
 271                         ++str;
 272                         continue;
 273                 }
 274
 275                 /* process flags */
 276                 flags = 0;
 277                 repeat:
 278                         ++fmt;          /* this also skips first '%' */
 279                         switch (*fmt) {
 280                                 case '-': flags |= LEFT; goto repeat;
 281                                 case '+': flags |= PLUS; goto repeat;
 282                                 case ' ': flags |= SPACE; goto repeat;
 283                                 case '#': flags |= SPECIAL; goto repeat;
 284                                 case '0': flags |= ZEROPAD; goto repeat;
 285                         }
 286
 287                 /* get field width */
 288                 field_width = -1;
 289                 if (isdigit(*fmt))
 290                         field_width = skip_atoi(&fmt);
 291                 else if (*fmt == '*') {
 292                         ++fmt;
 293                         /* it's the next argument */
 294                         field_width = va_arg(args, int);
 295                         if (field_width < 0) {
 296                                 field_width = -field_width;
 297                                 flags |= LEFT;
 298                         }
 299                 }
 300
 301                 /* get the precision */
 302                 precision = -1;
 303                 if (*fmt == '.') {
 304                         ++fmt;
 305                         if (isdigit(*fmt))
 306                                 precision = skip_atoi(&fmt);
 307                         else if (*fmt == '*') {
 308                                 ++fmt;
 309                                 /* it's the next argument */
 310                                 precision = va_arg(args, int);
 311                         }
 312                         if (precision < 0)
 313                                 precision = 0;
 314                 }
 315
 316                 /* get the conversion qualifier */
 317                 qualifier = -1;
 318                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || *fmt == 'w') {
 319                         qualifier = *fmt;
 320                         ++fmt;
 321                 } else if (*fmt == 'I' && *(fmt+1) == '6' && *(fmt+2) == '4') {
 322                         qualifier = *fmt;
 323                         fmt += 3;
 324                 }
 325
 326                 /* default base */
 327                 base = 10;
 328
 329                 switch (*fmt) {
 330                 case 'c': /* finished */
 331                         if (!(flags & LEFT))
 332                                 while (--field_width > 0) {
 333                                         if (str <= end)
 334                                                 *str = ' ';
 335                                         ++str;
 336                                 }
 337                         if (qualifier == 'l' || qualifier == 'w') {
 338                                 if (str <= end)
 339                                         *str = (unsigned char)(wchar_t) va_arg(args, int);
 340                                 ++str;
 341                         } else {
 342                                 if (str <= end)
 343                                         *str = (unsigned char) va_arg(args, int);
 344                                 ++str;
 345                         }
 346                         while (--field_width > 0) {
 347                                 if (str <= end)
 348                                         *str = ' ';
 349                                 ++str;
 350                         }
 351                         continue;
 352
 353                 case 'C': /* finished */
 354                         if (!(flags & LEFT))
 355                                 while (--field_width > 0) {
 356                                         if (str <= end)
 357                                                 *str = ' ';
 358                                         ++str;
 359                                 }
 360                         if (qualifier == 'h') {
 361                                 if (str <= end)
 362                                         *str = (unsigned char) va_arg(args, int);
 363                                 ++str;
 364                         } else {
 365                                 if (str <= end)
 366                                         *str = (unsigned char)(wchar_t) va_arg(args, int);
 367                                 ++str;
 368                         }
 369                         while (--field_width > 0) {
 370                                 if (str <= end)
 371                                         *str = ' ';
 372                                 ++str;
 373                         }
 374                         continue;
 375
 376                 case 's': /* finished */
 377                         if (qualifier == 'l' || qualifier == 'w') {
 378                                 /* print unicode string */
 379                                 sw = va_arg(args, wchar_t *);
 380                                 str = stringw(str, end, sw, -1, field_width, precision, flags);
 381                         } else {
 382                                 /* print ascii string */
 383                                 s = va_arg(args, char *);
 384                                 str = string(str, end, s, -1,  field_width, precision, flags);
 385                         }
 386                         continue;
 387
 388                 case 'S':
 389                         if (qualifier == 'h') {
 390                                 /* print ascii string */
 391                                 s = va_arg(args, char *);
 392                                 str = string(str, end, s, -1,  field_width, precision, flags);
 393                         } else {
 394                                 /* print unicode string */
 395                                 sw = va_arg(args, wchar_t *);
 396                                 str = stringw(str, end, sw, -1, field_width, precision, flags);
 397                         }
 398                         continue;
 399
 400                 case 'Z':
 401                         if (qualifier == 'w') {
 402                                 /* print counted unicode string */
 403                                 PUNICODE_STRING pus = va_arg(args, PUNICODE_STRING);
 404                                 if ((pus == NULL) || (pus->Buffer == NULL)) {
 405                                         sw = NULL;
 406                                         len = -1;
 407                                 } else {
 408                                         sw = pus->Buffer;
 409                                         len = pus->Length / sizeof(WCHAR);
 410                                 }
 411                                 str = stringw(str, end, sw, len,  field_width, precision, flags);
 412                         } else {
 413                                 /* print counted ascii string */
 414                                 PANSI_STRING pus = va_arg(args, PANSI_STRING);
 415                                 if ((pus == NULL) || (pus->Buffer == NULL)) {
 416                                         s = NULL;
 417                                         len = -1;
 418                                 } else {
 419                                         s = pus->Buffer;
 420                                         len = pus->Length;
 421                                 }
 422                                 str = string(str, end, s, len,  field_width, precision, flags);
 423                         }
 424                         continue;
 425
 426                 case 'p':
 427                         if (field_width == -1) {
 428                                 field_width = 2 * sizeof(void *);
 429                                 flags |= ZEROPAD;
 430                         }
 431                         str = number(str, end,
 432                                 (unsigned long) va_arg(args, void *), 16,
 433                                 field_width, precision, flags);
 434                         continue;
 435
 436                 case 'n':
 437                         /* FIXME: What does C99 say about the overflow case here? */
 438                         if (qualifier == 'l') {
 439                                 long * ip = va_arg(args, long *);
 440                                 *ip = (str - buf);
 441                         } else {
 442                                 int * ip = va_arg(args, int *);
 443                                 *ip = (str - buf);
 444                         }
 445                         continue;
 446
 447                 /* integer number formats - set up the flags and "break" */
 448                 case 'o':
 449                         base = 8;
 450                         break;
 451
 452                 case 'b':
 453                         base = 2;
 454                         break;
 455
 456                 case 'X':
 457                         flags |= LARGE;
 458                 case 'x':
 459                         base = 16;
 460                         break;
 461
 462                 case 'd':
 463                 case 'i':
 464                         flags |= SIGN;
 465                 case 'u':
 466                         break;
 467
 468                 default:
 469                         if (*fmt != '%') {
 470                                 if (str <= end)
 471                                         *str = '%';
 472                                 ++str;
 473                         }
 474                         if (*fmt) {
 475                                 if (str <= end)
 476                                         *str = *fmt;
 477                                 ++str;
 478                         } else
 479                                 --fmt;
 480                         continue;
 481                 }
 482
 483                 if (qualifier == 'I')
 484                         num = va_arg(args, unsigned long long);
 485                 else if (qualifier == 'l')
 486                         num = va_arg(args, unsigned long);
 487                 else if (qualifier == 'h') {
 488                         if (flags & SIGN)
 489                                 num = va_arg(args, int);
 490                         else
 491                                 num = va_arg(args, unsigned int);
 492                 }
 493                 else {
 494                         if (flags & SIGN)
 495                                 num = va_arg(args, int);
 496                         else
 497                                 num = va_arg(args, unsigned int);
 498                 }
 499                 str = number(str, end, num, base, field_width, precision, flags);
 500         }
 501         if (str <= end)
 502                 *str = '\0';
 503         else if (cnt > 0)
 504                 /* don't write out a null byte if the buf size is zero */
 505                 *end = '\0';
 506         return str-buf;
 507 }
 508
 509
 510 int sprintf(char * buf, const char *fmt, ...)
 511 {
 512         va_list args;
 513         int i;
 514
 515         va_start(args, fmt);
 516         i=_vsnprintf(buf,INT_MAX,fmt,args);
 517         va_end(args);
 518         return i;
 519 }
 520
 521
 522 int _snprintf(char * buf, size_t cnt, const char *fmt, ...)
 523 {
 524         va_list args;
 525         int i;
 526
 527         va_start(args, fmt);
 528         i=_vsnprintf(buf,cnt,fmt,args);
 529         va_end(args);
 530         return i;
 531 }
 532
 533
 534 int vsprintf(char *buf, const char *fmt, va_list args)
 535 {
 536         return _vsnprintf(buf,INT_MAX,fmt,args);
 537 }
 538
 539 /* EOF */