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 /*
 245  * @implemented
 246  */
 247 int _vsnprintf(char *buf, size_t cnt, const char *fmt, va_list args)
 248 {
 249         int len;
 250         unsigned long long num;
 251         int base;
 252         char *str, *end;
 253         const char *s;
 254         const wchar_t *sw;
 255
 256         int flags;              /* flags to number() */
 257
 258         int field_width;        /* width of output field */
 259         int precision;          /* min. # of digits for integers; max
 260                                    number of chars for from string */
 261         int qualifier;          /* 'h', 'l', 'L', 'I' or 'w' for integer fields */
 262
 263         str = buf;
 264         end = buf + cnt - 1;
 265         if (end < buf - 1) {
 266                 end = ((void *) -1);
 267                 cnt = end - buf + 1;
 268         }
 269
 270         for ( ; *fmt ; ++fmt) {
 271                 if (*fmt != '%') {
 272                         if (str <= end)
 273                                 *str = *fmt;
 274                         ++str;
 275                         continue;
 276                 }
 277
 278                 /* process flags */
 279                 flags = 0;
 280                 repeat:
 281                         ++fmt;          /* this also skips first '%' */
 282                         switch (*fmt) {
 283                                 case '-': flags |= LEFT; goto repeat;
 284                                 case '+': flags |= PLUS; goto repeat;
 285                                 case ' ': flags |= SPACE; goto repeat;
 286                                 case '#': flags |= SPECIAL; goto repeat;
 287                                 case '0': flags |= ZEROPAD; goto repeat;
 288                         }
 289
 290                 /* get field width */
 291                 field_width = -1;
 292                 if (isdigit(*fmt))
 293                         field_width = skip_atoi(&fmt);
 294                 else if (*fmt == '*') {
 295                         ++fmt;
 296                         /* it's the next argument */
 297                         field_width = va_arg(args, int);
 298                         if (field_width < 0) {
 299                                 field_width = -field_width;
 300                                 flags |= LEFT;
 301                         }
 302                 }
 303
 304                 /* get the precision */
 305                 precision = -1;
 306                 if (*fmt == '.') {
 307                         ++fmt;
 308                         if (isdigit(*fmt))
 309                                 precision = skip_atoi(&fmt);
 310                         else if (*fmt == '*') {
 311                                 ++fmt;
 312                                 /* it's the next argument */
 313                                 precision = va_arg(args, int);
 314                         }
 315                         if (precision < 0)
 316                                 precision = 0;
 317                 }
 318
 319                 /* get the conversion qualifier */
 320                 qualifier = -1;
 321                 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || *fmt == 'w') {
 322                         qualifier = *fmt;
 323                         ++fmt;
 324                 } else if (*fmt == 'I' && *(fmt+1) == '6' && *(fmt+2) == '4') {
 325                         qualifier = *fmt;
 326                         fmt += 3;
 327                 }
 328
 329                 /* default base */
 330                 base = 10;
 331
 332                 switch (*fmt) {
 333                 case 'c': /* finished */
 334                         if (!(flags & LEFT))
 335                                 while (--field_width > 0) {
 336                                         if (str <= end)
 337                                                 *str = ' ';
 338                                         ++str;
 339                                 }
 340                         if (qualifier == 'l' || qualifier == 'w') {
 341                                 if (str <= end)
 342                                         *str = (unsigned char)(wchar_t) va_arg(args, int);
 343                                 ++str;
 344                         } else {
 345                                 if (str <= end)
 346                                         *str = (unsigned char) va_arg(args, int);
 347                                 ++str;
 348                         }
 349                         while (--field_width > 0) {
 350                                 if (str <= end)
 351                                         *str = ' ';
 352                                 ++str;
 353                         }
 354                         continue;
 355
 356                 case 'C': /* finished */
 357                         if (!(flags & LEFT))
 358                                 while (--field_width > 0) {
 359                                         if (str <= end)
 360                                                 *str = ' ';
 361                                         ++str;
 362                                 }
 363                         if (qualifier == 'h') {
 364                                 if (str <= end)
 365                                         *str = (unsigned char) va_arg(args, int);
 366                                 ++str;
 367                         } else {
 368                                 if (str <= end)
 369                                         *str = (unsigned char)(wchar_t) va_arg(args, int);
 370                                 ++str;
 371                         }
 372                         while (--field_width > 0) {
 373                                 if (str <= end)
 374                                         *str = ' ';
 375                                 ++str;
 376                         }
 377                         continue;
 378
 379                 case 's': /* finished */
 380                         if (qualifier == 'l' || qualifier == 'w') {
 381                                 /* print unicode string */
 382                                 sw = va_arg(args, wchar_t *);
 383                                 str = stringw(str, end, sw, -1, field_width, precision, flags);
 384                         } else {
 385                                 /* print ascii string */
 386                                 s = va_arg(args, char *);
 387                                 str = string(str, end, s, -1,  field_width, precision, flags);
 388                         }
 389                         continue;
 390
 391                 case 'S':
 392                         if (qualifier == 'h') {
 393                                 /* print ascii string */
 394                                 s = va_arg(args, char *);
 395                                 str = string(str, end, s, -1,  field_width, precision, flags);
 396                         } else {
 397                                 /* print unicode string */
 398                                 sw = va_arg(args, wchar_t *);
 399                                 str = stringw(str, end, sw, -1, field_width, precision, flags);
 400                         }
 401                         continue;
 402
 403                 case 'Z':
 404                         if (qualifier == 'w') {
 405                                 /* print counted unicode string */
 406                                 PUNICODE_STRING pus = va_arg(args, PUNICODE_STRING);
 407                                 if ((pus == NULL) || (pus->Buffer == NULL)) {
 408                                         sw = NULL;
 409                                         len = -1;
 410                                 } else {
 411                                         sw = pus->Buffer;
 412                                         len = pus->Length / sizeof(WCHAR);
 413                                 }
 414                                 str = stringw(str, end, sw, len,  field_width, precision, flags);
 415                         } else {
 416                                 /* print counted ascii string */
 417                                 PANSI_STRING pus = va_arg(args, PANSI_STRING);
 418                                 if ((pus == NULL) || (pus->Buffer == NULL)) {
 419                                         s = NULL;
 420                                         len = -1;
 421                                 } else {
 422                                         s = pus->Buffer;
 423                                         len = pus->Length;
 424                                 }
 425                                 str = string(str, end, s, len,  field_width, precision, flags);
 426                         }
 427                         continue;
 428
 429                 case 'p':
 430                         if (field_width == -1) {
 431                                 field_width = 2 * sizeof(void *);
 432                                 flags |= ZEROPAD;
 433                         }
 434                         str = number(str, end,
 435                                 (unsigned long) va_arg(args, void *), 16,
 436                                 field_width, precision, flags);
 437                         continue;
 438
 439                 case 'n':
 440                         /* FIXME: What does C99 say about the overflow case here? */
 441                         if (qualifier == 'l') {
 442                                 long * ip = va_arg(args, long *);
 443                                 *ip = (str - buf);
 444                         } else {
 445                                 int * ip = va_arg(args, int *);
 446                                 *ip = (str - buf);
 447                         }
 448                         continue;
 449
 450                 /* integer number formats - set up the flags and "break" */
 451                 case 'o':
 452                         base = 8;
 453                         break;
 454
 455                 case 'b':
 456                         base = 2;
 457                         break;
 458
 459                 case 'X':
 460                         flags |= LARGE;
 461                 case 'x':
 462                         base = 16;
 463                         break;
 464
 465                 case 'd':
 466                 case 'i':
 467                         flags |= SIGN;
 468                 case 'u':
 469                         break;
 470
 471                 default:
 472                         if (*fmt != '%') {
 473                                 if (str <= end)
 474                                         *str = '%';
 475                                 ++str;
 476                         }
 477                         if (*fmt) {
 478                                 if (str <= end)
 479                                         *str = *fmt;
 480                                 ++str;
 481                         } else
 482                                 --fmt;
 483                         continue;
 484                 }
 485
 486                 if (qualifier == 'I')
 487                         num = va_arg(args, unsigned long long);
 488                 else if (qualifier == 'l')
 489                         num = va_arg(args, unsigned long);
 490                 else if (qualifier == 'h') {
 491                         if (flags & SIGN)
 492                                 num = va_arg(args, int);
 493                         else
 494                                 num = va_arg(args, unsigned int);
 495                 }
 496                 else {
 497                         if (flags & SIGN)
 498                                 num = va_arg(args, int);
 499                         else
 500                                 num = va_arg(args, unsigned int);
 501                 }
 502                 str = number(str, end, num, base, field_width, precision, flags);
 503         }
 504         if (str <= end)
 505                 *str = '\0';
 506         else if (cnt > 0)
 507                 /* don't write out a null byte if the buf size is zero */
 508                 *end = '\0';
 509         return str-buf;
 510 }
 511
 512
 513 /*
 514  * @implemented
 515  */
 516 int sprintf(char * buf, const char *fmt, ...)
 517 {
 518         va_list args;
 519         int i;
 520
 521         va_start(args, fmt);
 522         i=_vsnprintf(buf,INT_MAX,fmt,args);
 523         va_end(args);
 524         return i;
 525 }
 526
 527
 528 /*
 529  * @implemented
 530  */
 531 int _snprintf(char * buf, size_t cnt, const char *fmt, ...)
 532 {
 533         va_list args;
 534         int i;
 535
 536         va_start(args, fmt);
 537         i=_vsnprintf(buf,cnt,fmt,args);
 538         va_end(args);
 539         return i;
 540 }
 541
 542
 543 /*
 544  * @implemented
 545  */
 546 int vsprintf(char *buf, const char *fmt, va_list args)
 547 {
 548         return _vsnprintf(buf,INT_MAX,fmt,args);
 549 }
 550
 551 /* EOF */