lib/libc/stdio/vfwscanf.c

   1 /*-
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Chris Torek.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 4. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * @(#)vfscanf.c        8.1 (Berkeley) 6/4/93
  33  * $FreeBSD: src/lib/libc/stdio/vfwscanf.c,v 1.17 2009/01/19 06:19:51 das Exp $
  34  * $DragonFly: src/lib/libc/stdio/vfwscanf.c,v 1.1 2005/07/25 00:37:41 joerg Exp $
  35  */
  36
  37 #include "namespace.h"
  38 #include <ctype.h>
  39 #include <inttypes.h>
  40 #include <limits.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <stddef.h>
  44 #include <stdarg.h>
  45 #include <string.h>
  46 #include <wchar.h>
  47 #include <wctype.h>
  48 #include "un-namespace.h"
  49
  50 #include "libc_private.h"
  51 #include "local.h"
  52 #include "priv_stdio.h"
  53
  54 #ifndef NO_FLOATING_POINT
  55 #include <locale.h>
  56 #endif
  57
  58 #define BUF             513     /* Maximum length of numeric string. */
  59
  60 /*
  61  * Flags used during conversion.
  62  */
  63 #define LONG            0x01    /* l: long or double */
  64 #define LONGDBL         0x02    /* L: long double */
  65 #define SHORT           0x04    /* h: short */
  66 #define SUPPRESS        0x08    /* *: suppress assignment */
  67 #define POINTER         0x10    /* p: void * (as hex) */
  68 #define NOSKIP          0x20    /* [ or c: do not skip blanks */
  69 #define LONGLONG        0x400   /* ll: long long (+ deprecated q: quad) */
  70 #define INTMAXT         0x800   /* j: intmax_t */
  71 #define PTRDIFFT        0x1000  /* t: ptrdiff_t */
  72 #define SIZET           0x2000  /* z: size_t */
  73 #define SHORTSHORT      0x4000  /* hh: char */
  74 #define UNSIGNED        0x8000  /* %[oupxX] conversions */
  75
  76 /*
  77  * The following are used in integral conversions only:
  78  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
  79  */
  80 #define SIGNOK          0x40    /* +/- is (still) legal */
  81 #define NDIGITS         0x80    /* no digits detected */
  82 #define PFXOK           0x100   /* 0x prefix is (still) legal */
  83 #define NZDIGITS        0x200   /* no zero digits detected */
  84 #define HAVESIGN        0x10000 /* sign detected */
  85
  86 /*
  87  * Conversion types.
  88  */
  89 #define CT_CHAR         0       /* %c conversion */
  90 #define CT_CCL          1       /* %[...] conversion */
  91 #define CT_STRING       2       /* %s conversion */
  92 #define CT_INT          3       /* %[dioupxX] conversion */
  93 #define CT_FLOAT        4       /* %[efgEFG] conversion */
  94
  95 #ifndef NO_FLOATING_POINT
  96 static int parsefloat(FILE *, wchar_t *, wchar_t *);
  97 #endif
  98
  99 #define INCCL(_c)       \
 100         (cclcompl ? (wmemchr(ccls, (_c), ccle - ccls) == NULL) : \
 101         (wmemchr(ccls, (_c), ccle - ccls) != NULL))
 102
 103 static const mbstate_t initial_mbs;
 104
 105 /*
 106  * MT-safe version.
 107  */
 108 int
 109 vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap)
 110 {
 111         int ret;
 112
 113         FLOCKFILE(fp);
 114         ORIENT(fp, 1);
 115         ret = __vfwscanf(fp, fmt, ap);
 116         FUNLOCKFILE(fp);
 117         return (ret);
 118 }
 119
 120 /*
 121  * Non-MT-safe version.
 122  */
 123 int
 124 __vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap)
 125 {
 126         wint_t c;               /* character from format, or conversion */
 127         size_t width;           /* field width, or 0 */
 128         wchar_t *p;             /* points into all kinds of strings */
 129         int n;                  /* handy integer */
 130         int flags;              /* flags as defined above */
 131         wchar_t *p0;            /* saves original value of p when necessary */
 132         int nassigned;          /* number of fields assigned */
 133         int nconversions;       /* number of conversions */
 134         int nread;              /* number of characters consumed from fp */
 135         int base;               /* base argument to conversion function */
 136         wchar_t buf[BUF];       /* buffer for numeric conversions */
 137         const wchar_t *ccls;    /* character class start */
 138         const wchar_t *ccle;    /* character class end */
 139         int cclcompl;           /* ccl is complemented? */
 140         wint_t wi;              /* handy wint_t */
 141         char *mbp;              /* multibyte string pointer for %c %s %[ */
 142         size_t nconv;           /* number of bytes in mb. conversion */
 143         char mbbuf[MB_LEN_MAX]; /* temporary mb. character buffer */
 144         mbstate_t mbs;
 145
 146         /* `basefix' is used to avoid `if' tests in the integer scanner */
 147         static short basefix[17] =
 148                 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
 149
 150         nassigned = 0;
 151         nconversions = 0;
 152         nread = 0;
 153         ccls = ccle = NULL;
 154         for (;;) {
 155                 c = *fmt++;
 156                 if (c == 0)
 157                         return (nassigned);
 158                 if (iswspace(c)) {
 159                         while ((c = __fgetwc_unlock(fp)) != WEOF &&
 160                             iswspace(c))
 161                                 ;
 162                         if (c != WEOF)
 163                                 ungetwc(c, fp);
 164                         continue;
 165                 }
 166                 if (c != '%')
 167                         goto literal;
 168                 width = 0;
 169                 flags = 0;
 170                 /*
 171                  * switch on the format.  continue if done;
 172                  * break once format type is derived.
 173                  */
 174 again:          c = *fmt++;
 175                 switch (c) {
 176                 case '%':
 177 literal:
 178                         if ((wi = __fgetwc_unlock(fp)) == WEOF)
 179                                 goto input_failure;
 180                         if (wi != c) {
 181                                 ungetwc(wi, fp);
 182                                 goto input_failure;
 183                         }
 184                         nread++;
 185                         continue;
 186
 187                 case '*':
 188                         flags |= SUPPRESS;
 189                         goto again;
 190                 case 'j':
 191                         flags |= INTMAXT;
 192                         goto again;
 193                 case 'l':
 194                         if (flags & LONG) {
 195                                 flags &= ~LONG;
 196                                 flags |= LONGLONG;
 197                         } else
 198                                 flags |= LONG;
 199                         goto again;
 200                 case 'q':
 201                         flags |= LONGLONG;      /* not quite */
 202                         goto again;
 203                 case 't':
 204                         flags |= PTRDIFFT;
 205                         goto again;
 206                 case 'z':
 207                         flags |= SIZET;
 208                         goto again;
 209                 case 'L':
 210                         flags |= LONGDBL;
 211                         goto again;
 212                 case 'h':
 213                         if (flags & SHORT) {
 214                                 flags &= ~SHORT;
 215                                 flags |= SHORTSHORT;
 216                         } else
 217                                 flags |= SHORT;
 218                         goto again;
 219
 220                 case '0': case '1': case '2': case '3': case '4':
 221                 case '5': case '6': case '7': case '8': case '9':
 222                         width = width * 10 + c - '0';
 223                         goto again;
 224
 225                 /*
 226                  * Conversions.
 227                  */
 228                 case 'd':
 229                         c = CT_INT;
 230                         base = 10;
 231                         break;
 232
 233                 case 'i':
 234                         c = CT_INT;
 235                         base = 0;
 236                         break;
 237
 238                 case 'o':
 239                         c = CT_INT;
 240                         flags |= UNSIGNED;
 241                         base = 8;
 242                         break;
 243
 244                 case 'u':
 245                         c = CT_INT;
 246                         flags |= UNSIGNED;
 247                         base = 10;
 248                         break;
 249
 250                 case 'X':
 251                 case 'x':
 252                         flags |= PFXOK; /* enable 0x prefixing */
 253                         c = CT_INT;
 254                         flags |= UNSIGNED;
 255                         base = 16;
 256                         break;
 257
 258 #ifndef NO_FLOATING_POINT
 259                 case 'A': case 'E': case 'F': case 'G':
 260                 case 'a': case 'e': case 'f': case 'g':
 261                         c = CT_FLOAT;
 262                         break;
 263 #endif
 264
 265                 case 'S':
 266                         flags |= LONG;
 267                         /* FALLTHROUGH */
 268                 case 's':
 269                         c = CT_STRING;
 270                         break;
 271
 272                 case '[':
 273                         ccls = fmt;
 274                         if (*fmt == '^') {
 275                                 cclcompl = 1;
 276                                 fmt++;
 277                         } else
 278                                 cclcompl = 0;
 279                         if (*fmt == ']')
 280                                 fmt++;
 281                         while (*fmt != '\0' && *fmt != ']')
 282                                 fmt++;
 283                         ccle = fmt;
 284                         fmt++;
 285                         flags |= NOSKIP;
 286                         c = CT_CCL;
 287                         break;
 288
 289                 case 'C':
 290                         flags |= LONG;
 291                         /* FALLTHROUGH */
 292                 case 'c':
 293                         flags |= NOSKIP;
 294                         c = CT_CHAR;
 295                         break;
 296
 297                 case 'p':       /* pointer format is like hex */
 298                         flags |= POINTER | PFXOK;
 299                         c = CT_INT;             /* assumes sizeof(uintmax_t) */
 300                         flags |= UNSIGNED;      /*      >= sizeof(uintptr_t) */
 301                         base = 16;
 302                         break;
 303
 304                 case 'n':
 305                         nconversions++;
 306                         if (flags & SUPPRESS)   /* ??? */
 307                                 continue;
 308                         if (flags & SHORTSHORT)
 309                                 *va_arg(ap, char *) = nread;
 310                         else if (flags & SHORT)
 311                                 *va_arg(ap, short *) = nread;
 312                         else if (flags & LONG)
 313                                 *va_arg(ap, long *) = nread;
 314                         else if (flags & LONGLONG)
 315                                 *va_arg(ap, long long *) = nread;
 316                         else if (flags & INTMAXT)
 317                                 *va_arg(ap, intmax_t *) = nread;
 318                         else if (flags & SIZET)
 319                                 *va_arg(ap, size_t *) = nread;
 320                         else if (flags & PTRDIFFT)
 321                                 *va_arg(ap, ptrdiff_t *) = nread;
 322                         else
 323                                 *va_arg(ap, int *) = nread;
 324                         continue;
 325
 326                 default:
 327                         goto match_failure;
 328
 329                 /*
 330                  * Disgusting backwards compatibility hack.     XXX
 331                  */
 332                 case '\0':      /* compat */
 333                         return (EOF);
 334                 }
 335
 336                 /*
 337                  * Consume leading white space, except for formats
 338                  * that suppress this.
 339                  */
 340                 if ((flags & NOSKIP) == 0) {
 341                         while ((wi = __fgetwc_unlock(fp)) != WEOF && iswspace(wi))
 342                                 nread++;
 343                         if (wi == WEOF)
 344                                 goto input_failure;
 345                         ungetwc(wi, fp);
 346                 }
 347
 348                 /*
 349                  * Do the conversion.
 350                  */
 351                 switch (c) {
 352
 353                 case CT_CHAR:
 354                         /* scan arbitrary characters (sets NOSKIP) */
 355                         if (width == 0)
 356                                 width = 1;
 357                         if (flags & LONG) {
 358                                 if (!(flags & SUPPRESS))
 359                                         p = va_arg(ap, wchar_t *);
 360                                 n = 0;
 361                                 while (width-- != 0 &&
 362                                     (wi = __fgetwc_unlock(fp)) != WEOF) {
 363                                         if (!(flags & SUPPRESS))
 364                                                 *p++ = (wchar_t)wi;
 365                                         n++;
 366                                 }
 367                                 if (n == 0)
 368                                         goto input_failure;
 369                                 nread += n;
 370                                 if (!(flags & SUPPRESS))
 371                                         nassigned++;
 372                         } else {
 373                                 if (!(flags & SUPPRESS))
 374                                         mbp = va_arg(ap, char *);
 375                                 n = 0;
 376                                 mbs = initial_mbs;
 377                                 while (width != 0 &&
 378                                     (wi = __fgetwc_unlock(fp)) != WEOF) {
 379                                         if (width >= MB_CUR_MAX &&
 380                                             !(flags & SUPPRESS)) {
 381                                                 nconv = wcrtomb(mbp, wi, &mbs);
 382                                                 if (nconv == (size_t)-1)
 383                                                         goto input_failure;
 384                                         } else {
 385                                                 nconv = wcrtomb(mbbuf, wi,
 386                                                     &mbs);
 387                                                 if (nconv == (size_t)-1)
 388                                                         goto input_failure;
 389                                                 if (nconv > width) {
 390                                                         ungetwc(wi, fp);
 391                                                         break;
 392                                                 }
 393                                                 if (!(flags & SUPPRESS))
 394                                                         memcpy(mbp, mbbuf,
 395                                                             nconv);
 396                                         }
 397                                         if (!(flags & SUPPRESS))
 398                                                 mbp += nconv;
 399                                         width -= nconv;
 400                                         n++;
 401                                 }
 402                                 if (n == 0)
 403                                         goto input_failure;
 404                                 nread += n;
 405                                 if (!(flags & SUPPRESS))
 406                                         nassigned++;
 407                         }
 408                         nconversions++;
 409                         break;
 410
 411                 case CT_CCL:
 412                         /* scan a (nonempty) character class (sets NOSKIP) */
 413                         if (width == 0)
 414                                 width = (size_t)~0;     /* `infinity' */
 415                         /* take only those things in the class */
 416                         if ((flags & SUPPRESS) && (flags & LONG)) {
 417                                 n = 0;
 418                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 419                                     width-- != 0 && INCCL(wi))
 420                                         n++;
 421                                 if (wi != WEOF)
 422                                         ungetwc(wi, fp);
 423                                 if (n == 0)
 424                                         goto match_failure;
 425                         } else if (flags & LONG) {
 426                                 p0 = p = va_arg(ap, wchar_t *);
 427                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 428                                     width-- != 0 && INCCL(wi))
 429                                         *p++ = (wchar_t)wi;
 430                                 if (wi != WEOF)
 431                                         ungetwc(wi, fp);
 432                                 n = p - p0;
 433                                 if (n == 0)
 434                                         goto match_failure;
 435                                 *p = 0;
 436                                 nassigned++;
 437                         } else {
 438                                 if (!(flags & SUPPRESS))
 439                                         mbp = va_arg(ap, char *);
 440                                 n = 0;
 441                                 mbs = initial_mbs;
 442                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 443                                     width != 0 && INCCL(wi)) {
 444                                         if (width >= MB_CUR_MAX &&
 445                                            !(flags & SUPPRESS)) {
 446                                                 nconv = wcrtomb(mbp, wi, &mbs);
 447                                                 if (nconv == (size_t)-1)
 448                                                         goto input_failure;
 449                                         } else {
 450                                                 nconv = wcrtomb(mbbuf, wi,
 451                                                     &mbs);
 452                                                 if (nconv == (size_t)-1)
 453                                                         goto input_failure;
 454                                                 if (nconv > width)
 455                                                         break;
 456                                                 if (!(flags & SUPPRESS))
 457                                                         memcpy(mbp, mbbuf,
 458                                                             nconv);
 459                                         }
 460                                         if (!(flags & SUPPRESS))
 461                                                 mbp += nconv;
 462                                         width -= nconv;
 463                                         n++;
 464                                 }
 465                                 if (wi != WEOF)
 466                                         ungetwc(wi, fp);
 467                                 if (!(flags & SUPPRESS)) {
 468                                         *mbp = 0;
 469                                         nassigned++;
 470                                 }
 471                         }
 472                         nread += n;
 473                         nconversions++;
 474                         break;
 475
 476                 case CT_STRING:
 477                         /* like CCL, but zero-length string OK, & no NOSKIP */
 478                         if (width == 0)
 479                                 width = (size_t)~0;
 480                         if ((flags & SUPPRESS) && (flags & LONG)) {
 481                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 482                                     width-- != 0 &&
 483                                     !iswspace(wi))
 484                                         nread++;
 485                                 if (wi != WEOF)
 486                                         ungetwc(wi, fp);
 487                         } else if (flags & LONG) {
 488                                 p0 = p = va_arg(ap, wchar_t *);
 489                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 490                                     width-- != 0 &&
 491                                     !iswspace(wi)) {
 492                                         *p++ = (wchar_t)wi;
 493                                         nread++;
 494                                 }
 495                                 if (wi != WEOF)
 496                                         ungetwc(wi, fp);
 497                                 *p = '\0';
 498                                 nassigned++;
 499                         } else {
 500                                 if (!(flags & SUPPRESS))
 501                                         mbp = va_arg(ap, char *);
 502                                 mbs = initial_mbs;
 503                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 504                                     width != 0 &&
 505                                     !iswspace(wi)) {
 506                                         if (width >= MB_CUR_MAX &&
 507                                             !(flags & SUPPRESS)) {
 508                                                 nconv = wcrtomb(mbp, wi, &mbs);
 509                                                 if (nconv == (size_t)-1)
 510                                                         goto input_failure;
 511                                         } else {
 512                                                 nconv = wcrtomb(mbbuf, wi,
 513                                                     &mbs);
 514                                                 if (nconv == (size_t)-1)
 515                                                         goto input_failure;
 516                                                 if (nconv > width)
 517                                                         break;
 518                                                 if (!(flags & SUPPRESS))
 519                                                         memcpy(mbp, mbbuf,
 520                                                             nconv);
 521                                         }
 522                                         if (!(flags & SUPPRESS))
 523                                                 mbp += nconv;
 524                                         width -= nconv;
 525                                         nread++;
 526                                 }
 527                                 if (wi != WEOF)
 528                                         ungetwc(wi, fp);
 529                                 if (!(flags & SUPPRESS)) {
 530                                         *mbp = 0;
 531                                         nassigned++;
 532                                 }
 533                         }
 534                         nconversions++;
 535                         continue;
 536
 537                 case CT_INT:
 538                         /* scan an integer as if by the conversion function */
 539                         if (width == 0 || width > sizeof(buf) /
 540                             sizeof(*buf) - 1)
 541                                 width = sizeof(buf) / sizeof(*buf) - 1;
 542                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 543                         for (p = buf; width; width--) {
 544                                 c = __fgetwc_unlock(fp);
 545                                 /*
 546                                  * Switch on the character; `goto ok'
 547                                  * if we accept it as a part of number.
 548                                  */
 549                                 switch (c) {
 550
 551                                 /*
 552                                  * The digit 0 is always legal, but is
 553                                  * special.  For %i conversions, if no
 554                                  * digits (zero or nonzero) have been
 555                                  * scanned (only signs), we will have
 556                                  * base==0.  In that case, we should set
 557                                  * it to 8 and enable 0x prefixing.
 558                                  * Also, if we have not scanned zero digits
 559                                  * before this, do not turn off prefixing
 560                                  * (someone else will turn it off if we
 561                                  * have scanned any nonzero digits).
 562                                  */
 563                                 case '0':
 564                                         if (base == 0) {
 565                                                 base = 8;
 566                                                 flags |= PFXOK;
 567                                         }
 568                                         if (flags & NZDIGITS)
 569                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 570                                         else
 571                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 572                                         goto ok;
 573
 574                                 /* 1 through 7 always legal */
 575                                 case '1': case '2': case '3':
 576                                 case '4': case '5': case '6': case '7':
 577                                         base = basefix[base];
 578                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 579                                         goto ok;
 580
 581                                 /* digits 8 and 9 ok iff decimal or hex */
 582                                 case '8': case '9':
 583                                         base = basefix[base];
 584                                         if (base <= 8)
 585                                                 break;  /* not legal here */
 586                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 587                                         goto ok;
 588
 589                                 /* letters ok iff hex */
 590                                 case 'A': case 'B': case 'C':
 591                                 case 'D': case 'E': case 'F':
 592                                 case 'a': case 'b': case 'c':
 593                                 case 'd': case 'e': case 'f':
 594                                         /* no need to fix base here */
 595                                         if (base <= 10)
 596                                                 break;  /* not legal here */
 597                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 598                                         goto ok;
 599
 600                                 /* sign ok only as first character */
 601                                 case '+': case '-':
 602                                         if (flags & SIGNOK) {
 603                                                 flags &= ~SIGNOK;
 604                                                 flags |= HAVESIGN;
 605                                                 goto ok;
 606                                         }
 607                                         break;
 608
 609                                 /*
 610                                  * x ok iff flag still set & 2nd char (or
 611                                  * 3rd char if we have a sign).
 612                                  */
 613                                 case 'x': case 'X':
 614                                         if (flags & PFXOK && p ==
 615                                             buf + 1 + !!(flags & HAVESIGN)) {
 616                                                 base = 16;      /* if %i */
 617                                                 flags &= ~PFXOK;
 618                                                 goto ok;
 619                                         }
 620                                         break;
 621                                 }
 622
 623                                 /*
 624                                  * If we got here, c is not a legal character
 625                                  * for a number.  Stop accumulating digits.
 626                                  */
 627                                 if (c != WEOF)
 628                                         ungetwc(c, fp);
 629                                 break;
 630                 ok:
 631                                 /*
 632                                  * c is legal: store it and look at the next.
 633                                  */
 634                                 *p++ = (wchar_t)c;
 635                         }
 636                         /*
 637                          * If we had only a sign, it is no good; push
 638                          * back the sign.  If the number ends in `x',
 639                          * it was [sign] '0' 'x', so push back the x
 640                          * and treat it as [sign] '0'.
 641                          */
 642                         if (flags & NDIGITS) {
 643                                 if (p > buf)
 644                                         ungetwc(*--p, fp);
 645                                 goto match_failure;
 646                         }
 647                         c = p[-1];
 648                         if (c == 'x' || c == 'X') {
 649                                 --p;
 650                                 ungetwc(c, fp);
 651                         }
 652                         if ((flags & SUPPRESS) == 0) {
 653                                 uintmax_t res;
 654
 655                                 *p = 0;
 656                                 if ((flags & UNSIGNED) == 0)
 657                                     res = wcstoimax(buf, NULL, base);
 658                                 else
 659                                     res = wcstoumax(buf, NULL, base);
 660                                 if (flags & POINTER)
 661                                         *va_arg(ap, void **) =
 662                                                         (void *)(uintptr_t)res;
 663                                 else if (flags & SHORTSHORT)
 664                                         *va_arg(ap, char *) = res;
 665                                 else if (flags & SHORT)
 666                                         *va_arg(ap, short *) = res;
 667                                 else if (flags & LONG)
 668                                         *va_arg(ap, long *) = res;
 669                                 else if (flags & LONGLONG)
 670                                         *va_arg(ap, long long *) = res;
 671                                 else if (flags & INTMAXT)
 672                                         *va_arg(ap, intmax_t *) = res;
 673                                 else if (flags & PTRDIFFT)
 674                                         *va_arg(ap, ptrdiff_t *) = res;
 675                                 else if (flags & SIZET)
 676                                         *va_arg(ap, size_t *) = res;
 677                                 else
 678                                         *va_arg(ap, int *) = res;
 679                                 nassigned++;
 680                         }
 681                         nread += p - buf;
 682                         nconversions++;
 683                         break;
 684
 685 #ifndef NO_FLOATING_POINT
 686                 case CT_FLOAT:
 687                         /* scan a floating point number as if by strtod */
 688                         if (width == 0 || width > sizeof(buf) /
 689                             sizeof(*buf) - 1)
 690                                 width = sizeof(buf) / sizeof(*buf) - 1;
 691                         if ((width = parsefloat(fp, buf, buf + width)) == 0)
 692                                 goto match_failure;
 693                         if ((flags & SUPPRESS) == 0) {
 694                                 if (flags & LONGDBL) {
 695                                         long double res = wcstold(buf, &p);
 696                                         *va_arg(ap, long double *) = res;
 697                                 } else if (flags & LONG) {
 698                                         double res = wcstod(buf, &p);
 699                                         *va_arg(ap, double *) = res;
 700                                 } else {
 701                                         float res = wcstof(buf, &p);
 702                                         *va_arg(ap, float *) = res;
 703                                 }
 704                                 nassigned++;
 705                         }
 706                         nread += width;
 707                         nconversions++;
 708                         break;
 709 #endif /* !NO_FLOATING_POINT */
 710                 }
 711         }
 712 input_failure:
 713         return (nconversions != 0 ? nassigned : EOF);
 714 match_failure:
 715         return (nassigned);
 716 }
 717
 718 #ifndef NO_FLOATING_POINT
 719 static int
 720 parsefloat(FILE *fp, wchar_t *buf, wchar_t *end)
 721 {
 722         mbstate_t mbs;
 723         size_t nconv;
 724         wchar_t *commit, *p;
 725         int infnanpos = 0;
 726         enum {
 727                 S_START, S_GOTSIGN, S_INF, S_NAN, S_DONE, S_MAYBEHEX,
 728                 S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
 729         } state = S_START;
 730         wchar_t c;
 731         wchar_t decpt;
 732         _Bool gotmantdig = 0, ishex = 0;
 733
 734         mbs = initial_mbs;
 735         nconv = mbrtowc(&decpt, localeconv()->decimal_point, MB_CUR_MAX, &mbs);
 736         if (nconv == (size_t)-1 || nconv == (size_t)-2)
 737                 decpt = '.';    /* failsafe */
 738
 739         /*
 740          * We set commit = p whenever the string we have read so far
 741          * constitutes a valid representation of a floating point
 742          * number by itself.  At some point, the parse will complete
 743          * or fail, and we will ungetc() back to the last commit point.
 744          * To ensure that the file offset gets updated properly, it is
 745          * always necessary to read at least one character that doesn't
 746          * match; thus, we can't short-circuit "infinity" or "nan(...)".
 747          */
 748         commit = buf - 1;
 749         c = WEOF;
 750         for (p = buf; p < end; ) {
 751                 if ((c = __fgetwc_unlock(fp)) == WEOF)
 752                         break;
 753 reswitch:
 754                 switch (state) {
 755                 case S_START:
 756                         state = S_GOTSIGN;
 757                         if (c == '-' || c == '+')
 758                                 break;
 759                         else
 760                                 goto reswitch;
 761                 case S_GOTSIGN:
 762                         switch (c) {
 763                         case '0':
 764                                 state = S_MAYBEHEX;
 765                                 commit = p;
 766                                 break;
 767                         case 'I':
 768                         case 'i':
 769                                 state = S_INF;
 770                                 break;
 771                         case 'N':
 772                         case 'n':
 773                                 state = S_NAN;
 774                                 break;
 775                         default:
 776                                 state = S_DIGITS;
 777                                 goto reswitch;
 778                         }
 779                         break;
 780                 case S_INF:
 781                         if (infnanpos > 6 ||
 782                             (c != "nfinity"[infnanpos] &&
 783                              c != "NFINITY"[infnanpos]))
 784                                 goto parsedone;
 785                         if (infnanpos == 1 || infnanpos == 6)
 786                                 commit = p;     /* inf or infinity */
 787                         infnanpos++;
 788                         break;
 789                 case S_NAN:
 790                         switch (infnanpos) {
 791                         case 0:
 792                                 if (c != 'A' && c != 'a')
 793                                         goto parsedone;
 794                                 break;
 795                         case 1:
 796                                 if (c != 'N' && c != 'n')
 797                                         goto parsedone;
 798                                 else
 799                                         commit = p;
 800                                 break;
 801                         case 2:
 802                                 if (c != '(')
 803                                         goto parsedone;
 804                                 break;
 805                         default:
 806                                 if (c == ')') {
 807                                         commit = p;
 808                                         state = S_DONE;
 809                                 } else if (!iswalnum(c) && c != '_')
 810                                         goto parsedone;
 811                                 break;
 812                         }
 813                         infnanpos++;
 814                         break;
 815                 case S_DONE:
 816                         goto parsedone;
 817                 case S_MAYBEHEX:
 818                         state = S_DIGITS;
 819                         if (c == 'X' || c == 'x') {
 820                                 ishex = 1;
 821                                 break;
 822                         } else {        /* we saw a '0', but no 'x' */
 823                                 gotmantdig = 1;
 824                                 goto reswitch;
 825                         }
 826                 case S_DIGITS:
 827                         if ((ishex && iswxdigit(c)) || iswdigit(c))
 828                                 gotmantdig = 1;
 829                         else {
 830                                 state = S_FRAC;
 831                                 if (c != decpt)
 832                                         goto reswitch;
 833                         }
 834                         if (gotmantdig)
 835                                 commit = p;
 836                         break;
 837                 case S_FRAC:
 838                         if (((c == 'E' || c == 'e') && !ishex) ||
 839                             ((c == 'P' || c == 'p') && ishex)) {
 840                                 if (!gotmantdig)
 841                                         goto parsedone;
 842                                 else
 843                                         state = S_EXP;
 844                         } else if ((ishex && iswxdigit(c)) || iswdigit(c)) {
 845                                 commit = p;
 846                                 gotmantdig = 1;
 847                         } else
 848                                 goto parsedone;
 849                         break;
 850                 case S_EXP:
 851                         state = S_EXPDIGITS;
 852                         if (c == '-' || c == '+')
 853                                 break;
 854                         else
 855                                 goto reswitch;
 856                 case S_EXPDIGITS:
 857                         if (iswdigit(c))
 858                                 commit = p;
 859                         else
 860                                 goto parsedone;
 861                         break;
 862                 default:
 863                         abort();
 864                 }
 865                 *p++ = c;
 866                 c = WEOF;
 867         }
 868
 869 parsedone:
 870         if (c != WEOF)
 871                 ungetwc(c, fp);
 872         while (commit < --p)
 873                 ungetwc(*p, fp);
 874         *++commit = '\0';
 875         return (commit - buf);
 876 }
 877 #endif