lib/libc/stdio/vfwscanf.c

   1 /*      $NetBSD: vfwscanf.c,v 1.2 2005/06/12 05:48:41 lukem Exp $       */
   2 /*      $DragonFly: src/lib/libc/stdio/vfwscanf.c,v 1.1 2005/07/25 00:37:41 joerg Exp $ */
   3
   4 /*-
   5  * Copyright (c) 1990, 1993
   6  *      The Regents of the University of California.  All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * Chris Torek.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Berkeley and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 #include "namespace.h"
  41 #include <ctype.h>
  42 #include <inttypes.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <stddef.h>
  46 #include <stdarg.h>
  47 #include <string.h>
  48 #include <limits.h>
  49 #include <wchar.h>
  50 #include <wctype.h>
  51 #include "un-namespace.h"
  52
  53 #include "libc_private.h"
  54 #include "local.h"
  55 #include "priv_stdio.h"
  56
  57 #ifndef NO_FLOATING_POINT
  58 #include <locale.h>
  59 #endif
  60
  61 #define BUF             513     /* Maximum length of numeric string. */
  62
  63 /*
  64  * Flags used during conversion.
  65  */
  66 #define LONG            0x01    /* l: long or double */
  67 #define LONGDBL         0x02    /* L: long double */
  68 #define SHORT           0x04    /* h: short */
  69 #define SUPPRESS        0x08    /* *: suppress assignment */
  70 #define POINTER         0x10    /* p: void * (as hex) */
  71 #define NOSKIP          0x20    /* [ or c: do not skip blanks */
  72 #define LONGLONG        0x400   /* ll: quad_t (+ deprecated q: quad) */
  73 #define INTMAXT         0x800   /* j: intmax_t */
  74 #define PTRDIFFT        0x1000  /* t: ptrdiff_t */
  75 #define SIZET           0x2000  /* z: size_t */
  76 #define SHORTSHORT      0x4000  /* hh: char */
  77 #define UNSIGNED        0x8000  /* %[oupxX] conversions */
  78
  79 /*
  80  * The following are used in integral conversions only:
  81  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
  82  */
  83 #define SIGNOK          0x40    /* +/- is (still) legal */
  84 #define NDIGITS         0x80    /* no digits detected */
  85 #define PFXOK           0x100   /* 0x prefix is (still) legal */
  86 #define NZDIGITS        0x200   /* no zero digits detected */
  87 #define HAVESIGN        0x10000 /* sign detected */
  88
  89 /*
  90  * Conversion types.
  91  */
  92 #define CT_CHAR         0       /* %c conversion */
  93 #define CT_CCL          1       /* %[...] conversion */
  94 #define CT_STRING       2       /* %s conversion */
  95 #define CT_INT          3       /* %[dioupxX] conversion */
  96 #define CT_FLOAT        4       /* %[efgEFG] conversion */
  97
  98 static int parsefloat(FILE *, wchar_t *, wchar_t *);
  99
 100 #define INCCL(_c)       \
 101         (cclcompl ? (wmemchr(ccls, (_c), (size_t)(ccle - ccls)) == NULL) : \
 102         (wmemchr(ccls, (_c), (size_t)(ccle - ccls)) != NULL))
 103
 104 /*
 105  * MT-safe version.
 106  */
 107 int
 108 vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap)
 109 {
 110         int ret;
 111
 112         FLOCKFILE(fp);
 113         _SET_ORIENTATION(fp, 1);
 114         ret = __vfwscanf_unlocked(fp, fmt, ap);
 115         FUNLOCKFILE(fp);
 116         return (ret);
 117 }
 118
 119 /*
 120  * Non-MT-safe version.
 121  */
 122 int
 123 __vfwscanf_unlocked(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap)
 124 {
 125         wint_t c;               /* character from format, or conversion */
 126         size_t width;           /* field width, or 0 */
 127         wchar_t *p;             /* points into all kinds of strings */
 128         int n;                  /* handy integer */
 129         int flags;              /* flags as defined above */
 130         wchar_t *p0;            /* saves original value of p when necessary */
 131         int nassigned;          /* number of fields assigned */
 132         int nconversions;       /* number of conversions */
 133         int nread;              /* number of characters consumed from fp */
 134         int base;               /* base argument to conversion function */
 135         wchar_t buf[BUF];       /* buffer for numeric conversions */
 136         const wchar_t *ccls;    /* character class start */
 137         const wchar_t *ccle;    /* character class end */
 138         int cclcompl;           /* ccl is complemented? */
 139         wint_t wi;              /* handy wint_t */
 140         char *mbp;              /* multibyte string pointer for %c %s %[ */
 141         size_t nconv;           /* number of bytes in mb. conversion */
 142         char mbbuf[MB_LEN_MAX]; /* temporary mb. character buffer */
 143         static const mbstate_t initial;
 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         base = 0;
 155         cclcompl = 0;
 156         mbp = NULL;
 157         for (;;) {
 158                 c = *fmt++;
 159                 if (c == 0)
 160                         return (nassigned);
 161                 if (iswspace(c)) {
 162                         while ((c = __fgetwc_unlock(fp)) != WEOF &&
 163                             iswspace(c))
 164                                 ;
 165                         if (c != WEOF)
 166                                 ungetwc(c, fp);
 167                         continue;
 168                 }
 169                 if (c != '%')
 170                         goto literal;
 171                 width = 0;
 172                 flags = 0;
 173                 /*
 174                  * switch on the format.  continue if done;
 175                  * break once format type is derived.
 176                  */
 177 again:          c = *fmt++;
 178                 switch (c) {
 179                 case '%':
 180 literal:
 181                         if ((wi = __fgetwc_unlock(fp)) == WEOF)
 182                                 goto input_failure;
 183                         if (wi != c) {
 184                                 ungetwc(wi, fp);
 185                                 goto input_failure;
 186                         }
 187                         nread++;
 188                         continue;
 189
 190                 case '*':
 191                         flags |= SUPPRESS;
 192                         goto again;
 193                 case 'j':
 194                         flags |= INTMAXT;
 195                         goto again;
 196                 case 'l':
 197                         if (flags & LONG) {
 198                                 flags &= ~LONG;
 199                                 flags |= LONGLONG;
 200                         } else
 201                                 flags |= LONG;
 202                         goto again;
 203                 case 'q':
 204                         flags |= LONGLONG;      /* not quite */
 205                         goto again;
 206                 case 't':
 207                         flags |= PTRDIFFT;
 208                         goto again;
 209                 case 'z':
 210                         flags |= SIZET;
 211                         goto again;
 212                 case 'L':
 213                         flags |= LONGDBL;
 214                         goto again;
 215                 case 'h':
 216                         if (flags & SHORT) {
 217                                 flags &= ~SHORT;
 218                                 flags |= SHORTSHORT;
 219                         } else
 220                                 flags |= SHORT;
 221                         goto again;
 222
 223                 case '0': case '1': case '2': case '3': case '4':
 224                 case '5': case '6': case '7': case '8': case '9':
 225                         width = width * 10 + c - '0';
 226                         goto again;
 227
 228                 /*
 229                  * Conversions.
 230                  */
 231                 case 'd':
 232                         c = CT_INT;
 233                         base = 10;
 234                         break;
 235
 236                 case 'i':
 237                         c = CT_INT;
 238                         base = 0;
 239                         break;
 240
 241                 case 'o':
 242                         c = CT_INT;
 243                         flags |= UNSIGNED;
 244                         base = 8;
 245                         break;
 246
 247                 case 'u':
 248                         c = CT_INT;
 249                         flags |= UNSIGNED;
 250                         base = 10;
 251                         break;
 252
 253                 case 'X':
 254                 case 'x':
 255                         flags |= PFXOK; /* enable 0x prefixing */
 256                         c = CT_INT;
 257                         flags |= UNSIGNED;
 258                         base = 16;
 259                         break;
 260
 261 #ifndef NO_FLOATING_POINT
 262                 case 'A': case 'E': case 'F': case 'G':
 263                 case 'a': case 'e': case 'f': case 'g':
 264                         c = CT_FLOAT;
 265                         break;
 266 #endif
 267
 268                 case 'S':
 269                         flags |= LONG;
 270                         /* FALLTHROUGH */
 271                 case 's':
 272                         c = CT_STRING;
 273                         break;
 274
 275                 case '[':
 276                         ccls = fmt;
 277                         if (*fmt == '^') {
 278                                 cclcompl = 1;
 279                                 fmt++;
 280                         } else
 281                                 cclcompl = 0;
 282                         if (*fmt == ']')
 283                                 fmt++;
 284                         while (*fmt != '\0' && *fmt != ']')
 285                                 fmt++;
 286                         ccle = fmt;
 287                         fmt++;
 288                         flags |= NOSKIP;
 289                         c = CT_CCL;
 290                         break;
 291
 292                 case 'C':
 293                         flags |= LONG;
 294                         /* FALLTHROUGH */
 295                 case 'c':
 296                         flags |= NOSKIP;
 297                         c = CT_CHAR;
 298                         break;
 299
 300                 case 'p':       /* pointer format is like hex */
 301                         flags |= POINTER | PFXOK;
 302                         c = CT_INT;             /* assumes sizeof(uintmax_t) */
 303                         flags |= UNSIGNED;      /*      >= sizeof(uintptr_t) */
 304                         base = 16;
 305                         break;
 306
 307                 case 'n':
 308                         nconversions++;
 309                         if (flags & SUPPRESS)   /* ??? */
 310                                 continue;
 311                         if (flags & SHORTSHORT)
 312                                 *va_arg(ap, char *) = nread;
 313                         else if (flags & SHORT)
 314                                 *va_arg(ap, short *) = nread;
 315                         else if (flags & LONG)
 316                                 *va_arg(ap, long *) = nread;
 317                         else if (flags & LONGLONG)
 318                                 *va_arg(ap, quad_t *) = nread;
 319                         else if (flags & INTMAXT)
 320                                 *va_arg(ap, intmax_t *) = nread;
 321                         else if (flags & SIZET)
 322                                 *va_arg(ap, size_t *) = nread;
 323                         else if (flags & PTRDIFFT)
 324                                 *va_arg(ap, ptrdiff_t *) = nread;
 325                         else
 326                                 *va_arg(ap, int *) = nread;
 327                         continue;
 328
 329                 default:
 330                         goto match_failure;
 331
 332                 /*
 333                  * Disgusting backwards compatibility hack.     XXX
 334                  */
 335                 case '\0':      /* compat */
 336                         return (EOF);
 337                 }
 338
 339                 /*
 340                  * Consume leading white space, except for formats
 341                  * that suppress this.
 342                  */
 343                 if ((flags & NOSKIP) == 0) {
 344                         while ((wi = __fgetwc_unlock(fp)) != WEOF && iswspace(wi))
 345                                 nread++;
 346                         if (wi == WEOF)
 347                                 goto input_failure;
 348                         ungetwc(wi, fp);
 349                 }
 350
 351                 /*
 352                  * Do the conversion.
 353                  */
 354                 switch (c) {
 355
 356                 case CT_CHAR:
 357                         /* scan arbitrary characters (sets NOSKIP) */
 358                         if (width == 0)
 359                                 width = 1;
 360                         if (flags & LONG) {
 361                                 if (!(flags & SUPPRESS))
 362                                         p = va_arg(ap, wchar_t *);
 363                                 n = 0;
 364                                 while (width-- != 0 &&
 365                                     (wi = __fgetwc_unlock(fp)) != WEOF) {
 366                                         if (!(flags & SUPPRESS))
 367                                                 *p++ = (wchar_t)wi;
 368                                         n++;
 369                                 }
 370                                 if (n == 0)
 371                                         goto input_failure;
 372                                 nread += n;
 373                                 if (!(flags & SUPPRESS))
 374                                         nassigned++;
 375                         } else {
 376                                 if (!(flags & SUPPRESS))
 377                                         mbp = va_arg(ap, char *);
 378                                 n = 0;
 379                                 mbs = initial;
 380                                 while (width != 0 &&
 381                                     (wi = __fgetwc_unlock(fp)) != WEOF) {
 382                                         if (width >= MB_CUR_MAX &&
 383                                             !(flags & SUPPRESS)) {
 384                                                 nconv = wcrtomb(mbp, wi, &mbs);
 385                                                 if (nconv == (size_t)-1)
 386                                                         goto input_failure;
 387                                         } else {
 388                                                 nconv = wcrtomb(mbbuf, wi,
 389                                                     &mbs);
 390                                                 if (nconv == (size_t)-1)
 391                                                         goto input_failure;
 392                                                 if (nconv > width) {
 393                                                         ungetwc(wi, fp);
 394                                                         break;
 395                                                 }
 396                                                 if (!(flags & SUPPRESS))
 397                                                         memcpy(mbp, mbbuf,
 398                                                             nconv);
 399                                         }
 400                                         if (!(flags & SUPPRESS))
 401                                                 mbp += nconv;
 402                                         width -= nconv;
 403                                         n++;
 404                                 }
 405                                 if (n == 0)
 406                                         goto input_failure;
 407                                 nread += n;
 408                                 if (!(flags & SUPPRESS))
 409                                         nassigned++;
 410                         }
 411                         nconversions++;
 412                         break;
 413
 414                 case CT_CCL:
 415                         /* scan a (nonempty) character class (sets NOSKIP) */
 416                         if (width == 0)
 417                                 width = (size_t)~0;     /* `infinity' */
 418                         /* take only those things in the class */
 419                         if ((flags & SUPPRESS) && (flags & LONG)) {
 420                                 n = 0;
 421                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 422                                     width-- != 0 && INCCL(wi))
 423                                         n++;
 424                                 if (wi != WEOF)
 425                                         ungetwc(wi, fp);
 426                                 if (n == 0)
 427                                         goto match_failure;
 428                         } else if (flags & LONG) {
 429                                 p0 = p = va_arg(ap, wchar_t *);
 430                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 431                                     width-- != 0 && INCCL(wi))
 432                                         *p++ = (wchar_t)wi;
 433                                 if (wi != WEOF)
 434                                         ungetwc(wi, fp);
 435                                 n = p - p0;
 436                                 if (n == 0)
 437                                         goto match_failure;
 438                                 *p = 0;
 439                                 nassigned++;
 440                         } else {
 441                                 if (!(flags & SUPPRESS))
 442                                         mbp = va_arg(ap, char *);
 443                                 n = 0;
 444                                 mbs = initial;
 445                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 446                                     width != 0 && INCCL(wi)) {
 447                                         if (width >= MB_CUR_MAX &&
 448                                            !(flags & SUPPRESS)) {
 449                                                 nconv = wcrtomb(mbp, wi, &mbs);
 450                                                 if (nconv == (size_t)-1)
 451                                                         goto input_failure;
 452                                         } else {
 453                                                 nconv = wcrtomb(mbbuf, wi,
 454                                                     &mbs);
 455                                                 if (nconv == (size_t)-1)
 456                                                         goto input_failure;
 457                                                 if (nconv > width)
 458                                                         break;
 459                                                 if (!(flags & SUPPRESS))
 460                                                         memcpy(mbp, mbbuf,
 461                                                             nconv);
 462                                         }
 463                                         if (!(flags & SUPPRESS))
 464                                                 mbp += nconv;
 465                                         width -= nconv;
 466                                         n++;
 467                                 }
 468                                 if (wi != WEOF)
 469                                         ungetwc(wi, fp);
 470                                 if (!(flags & SUPPRESS)) {
 471                                         *mbp = 0;
 472                                         nassigned++;
 473                                 }
 474                         }
 475                         nread += n;
 476                         nconversions++;
 477                         break;
 478
 479                 case CT_STRING:
 480                         /* like CCL, but zero-length string OK, & no NOSKIP */
 481                         if (width == 0)
 482                                 width = (size_t)~0;
 483                         if ((flags & SUPPRESS) && (flags & LONG)) {
 484                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 485                                     width-- != 0 &&
 486                                     !iswspace(wi))
 487                                         nread++;
 488                                 if (wi != WEOF)
 489                                         ungetwc(wi, fp);
 490                         } else if (flags & LONG) {
 491                                 p0 = p = va_arg(ap, wchar_t *);
 492                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 493                                     width-- != 0 &&
 494                                     !iswspace(wi)) {
 495                                         *p++ = (wchar_t)wi;
 496                                         nread++;
 497                                 }
 498                                 if (wi != WEOF)
 499                                         ungetwc(wi, fp);
 500                                 *p = '\0';
 501                                 nassigned++;
 502                         } else {
 503                                 if (!(flags & SUPPRESS))
 504                                         mbp = va_arg(ap, char *);
 505                                 mbs = initial;
 506                                 while ((wi = __fgetwc_unlock(fp)) != WEOF &&
 507                                     width != 0 &&
 508                                     !iswspace(wi)) {
 509                                         if (width >= MB_CUR_MAX &&
 510                                             !(flags & SUPPRESS)) {
 511                                                 nconv = wcrtomb(mbp, wi, &mbs);
 512                                                 if (nconv == (size_t)-1)
 513                                                         goto input_failure;
 514                                         } else {
 515                                                 nconv = wcrtomb(mbbuf, wi,
 516                                                     &mbs);
 517                                                 if (nconv == (size_t)-1)
 518                                                         goto input_failure;
 519                                                 if (nconv > width)
 520                                                         break;
 521                                                 if (!(flags & SUPPRESS))
 522                                                         memcpy(mbp, mbbuf,
 523                                                             nconv);
 524                                         }
 525                                         if (!(flags & SUPPRESS))
 526                                                 mbp += nconv;
 527                                         width -= nconv;
 528                                         nread++;
 529                                 }
 530                                 if (wi != WEOF)
 531                                         ungetwc(wi, fp);
 532                                 if (!(flags & SUPPRESS)) {
 533                                         *mbp = 0;
 534                                         nassigned++;
 535                                 }
 536                         }
 537                         nconversions++;
 538                         continue;
 539
 540                 case CT_INT:
 541                         /* scan an integer as if by the conversion function */
 542                         if (width == 0 || width > sizeof(buf) /
 543                             sizeof(*buf) - 1)
 544                                 width = sizeof(buf) / sizeof(*buf) - 1;
 545                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 546                         for (p = buf; width; width--) {
 547                                 c = __fgetwc_unlock(fp);
 548                                 /*
 549                                  * Switch on the character; `goto ok'
 550                                  * if we accept it as a part of number.
 551                                  */
 552                                 switch (c) {
 553
 554                                 /*
 555                                  * The digit 0 is always legal, but is
 556                                  * special.  For %i conversions, if no
 557                                  * digits (zero or nonzero) have been
 558                                  * scanned (only signs), we will have
 559                                  * base==0.  In that case, we should set
 560                                  * it to 8 and enable 0x prefixing.
 561                                  * Also, if we have not scanned zero digits
 562                                  * before this, do not turn off prefixing
 563                                  * (someone else will turn it off if we
 564                                  * have scanned any nonzero digits).
 565                                  */
 566                                 case '0':
 567                                         if (base == 0) {
 568                                                 base = 8;
 569                                                 flags |= PFXOK;
 570                                         }
 571                                         if (flags & NZDIGITS)
 572                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 573                                         else
 574                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 575                                         goto ok;
 576
 577                                 /* 1 through 7 always legal */
 578                                 case '1': case '2': case '3':
 579                                 case '4': case '5': case '6': case '7':
 580                                         base = basefix[base];
 581                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 582                                         goto ok;
 583
 584                                 /* digits 8 and 9 ok iff decimal or hex */
 585                                 case '8': case '9':
 586                                         base = basefix[base];
 587                                         if (base <= 8)
 588                                                 break;  /* not legal here */
 589                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 590                                         goto ok;
 591
 592                                 /* letters ok iff hex */
 593                                 case 'A': case 'B': case 'C':
 594                                 case 'D': case 'E': case 'F':
 595                                 case 'a': case 'b': case 'c':
 596                                 case 'd': case 'e': case 'f':
 597                                         /* no need to fix base here */
 598                                         if (base <= 10)
 599                                                 break;  /* not legal here */
 600                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 601                                         goto ok;
 602
 603                                 /* sign ok only as first character */
 604                                 case '+': case '-':
 605                                         if (flags & SIGNOK) {
 606                                                 flags &= ~SIGNOK;
 607                                                 flags |= HAVESIGN;
 608                                                 goto ok;
 609                                         }
 610                                         break;
 611
 612                                 /*
 613                                  * x ok iff flag still set & 2nd char (or
 614                                  * 3rd char if we have a sign).
 615                                  */
 616                                 case 'x': case 'X':
 617                                         if (flags & PFXOK && p ==
 618                                             buf + 1 + !!(flags & HAVESIGN)) {
 619                                                 base = 16;      /* if %i */
 620                                                 flags &= ~PFXOK;
 621                                                 goto ok;
 622                                         }
 623                                         break;
 624                                 }
 625
 626                                 /*
 627                                  * If we got here, c is not a legal character
 628                                  * for a number.  Stop accumulating digits.
 629                                  */
 630                                 if (c != WEOF)
 631                                         ungetwc(c, fp);
 632                                 break;
 633                 ok:
 634                                 /*
 635                                  * c is legal: store it and look at the next.
 636                                  */
 637                                 *p++ = (wchar_t)c;
 638                         }
 639                         /*
 640                          * If we had only a sign, it is no good; push
 641                          * back the sign.  If the number ends in `x',
 642                          * it was [sign] '0' 'x', so push back the x
 643                          * and treat it as [sign] '0'.
 644                          */
 645                         if (flags & NDIGITS) {
 646                                 if (p > buf)
 647                                         ungetwc(*--p, fp);
 648                                 goto match_failure;
 649                         }
 650                         c = p[-1];
 651                         if (c == 'x' || c == 'X') {
 652                                 --p;
 653                                 ungetwc(c, fp);
 654                         }
 655                         if ((flags & SUPPRESS) == 0) {
 656                                 uintmax_t res;
 657
 658                                 *p = 0;
 659                                 if ((flags & UNSIGNED) == 0)
 660                                     res = wcstoimax(buf, NULL, base);
 661                                 else
 662                                     res = wcstoumax(buf, NULL, base);
 663                                 if (flags & POINTER)
 664                                         *va_arg(ap, void **) =
 665                                                         (void *)(uintptr_t)res;
 666                                 else if (flags & SHORTSHORT)
 667                                         *va_arg(ap, char *) = (char)res;
 668                                 else if (flags & SHORT)
 669                                         *va_arg(ap, short *) = (short)res;
 670                                 else if (flags & LONG)
 671                                         *va_arg(ap, long *) = (long)res;
 672                                 else if (flags & LONGLONG)
 673                                         *va_arg(ap, quad_t *) = res;
 674                                 else if (flags & INTMAXT)
 675                                         *va_arg(ap, intmax_t *) = res;
 676                                 else if (flags & PTRDIFFT)
 677                                         *va_arg(ap, ptrdiff_t *) = (ptrdiff_t)res;
 678                                 else if (flags & SIZET)
 679                                         *va_arg(ap, size_t *) = (size_t)res;
 680                                 else
 681                                         *va_arg(ap, int *) = (int)res;
 682                                 nassigned++;
 683                         }
 684                         nread += p - buf;
 685                         nconversions++;
 686                         break;
 687
 688 #ifndef NO_FLOATING_POINT
 689                 case CT_FLOAT:
 690                         /* scan a floating point number as if by strtod */
 691                         if (width == 0 || width > sizeof(buf) /
 692                             sizeof(*buf) - 1)
 693                                 width = sizeof(buf) / sizeof(*buf) - 1;
 694                         if ((width = parsefloat(fp, buf, buf + width)) == 0)
 695                                 goto match_failure;
 696                         if ((flags & SUPPRESS) == 0) {
 697 #ifdef notyet
 698                                 if (flags & LONGDBL) {
 699                                         long double res = wcstold(buf, &p);
 700                                         *va_arg(ap, long double *) = res;
 701                                 } else
 702 #endif
 703                                 if (flags & LONG) {
 704                                         double res = wcstod(buf, &p);
 705                                         *va_arg(ap, double *) = res;
 706 #ifdef notyet
 707                                 } else {
 708                                         float res = wcstof(buf, &p);
 709                                         *va_arg(ap, float *) = res;
 710 #endif
 711                                 }
 712 #ifdef DEBUG
 713                                 if (p - buf != width)
 714                                         abort();
 715 #endif
 716                                 nassigned++;
 717                         }
 718                         nread += width;
 719                         nconversions++;
 720                         break;
 721 #endif /* !NO_FLOATING_POINT */
 722                 }
 723         }
 724 input_failure:
 725         return (nconversions != 0 ? nassigned : EOF);
 726 match_failure:
 727         return (nassigned);
 728 }
 729
 730 #ifndef NO_FLOATING_POINT
 731 static int
 732 parsefloat(FILE *fp, wchar_t *buf, wchar_t *end)
 733 {
 734         wchar_t *commit, *p;
 735         int infnanpos = 0;
 736         enum {
 737                 S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX,
 738                 S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
 739         } state = S_START;
 740         wchar_t c;
 741         wchar_t decpt = (wchar_t)(unsigned char)*localeconv()->decimal_point;
 742         int gotmantdig = 0, ishex = 0;
 743
 744         /*
 745          * We set commit = p whenever the string we have read so far
 746          * constitutes a valid representation of a floating point
 747          * number by itself.  At some point, the parse will complete
 748          * or fail, and we will ungetc() back to the last commit point.
 749          * To ensure that the file offset gets updated properly, it is
 750          * always necessary to read at least one character that doesn't
 751          * match; thus, we can't short-circuit "infinity" or "nan(...)".
 752          */
 753         commit = buf - 1;
 754         c = WEOF;
 755         for (p = buf; p < end; ) {
 756                 if ((c = __fgetwc_unlock(fp)) == WEOF)
 757                         break;
 758 reswitch:
 759                 switch (state) {
 760                 case S_START:
 761                         state = S_GOTSIGN;
 762                         if (c == '-' || c == '+')
 763                                 break;
 764                         else
 765                                 goto reswitch;
 766                 case S_GOTSIGN:
 767                         switch (c) {
 768                         case '0':
 769                                 state = S_MAYBEHEX;
 770                                 commit = p;
 771                                 break;
 772                         case 'I':
 773                         case 'i':
 774                                 state = S_INF;
 775                                 break;
 776                         case 'N':
 777                         case 'n':
 778                                 state = S_NAN;
 779                                 break;
 780                         default:
 781                                 state = S_DIGITS;
 782                                 goto reswitch;
 783                         }
 784                         break;
 785                 case S_INF:
 786                         if (infnanpos > 6 ||
 787                             (c != "nfinity"[infnanpos] &&
 788                              c != "NFINITY"[infnanpos]))
 789                                 goto parsedone;
 790                         if (infnanpos == 1 || infnanpos == 6)
 791                                 commit = p;     /* inf or infinity */
 792                         infnanpos++;
 793                         break;
 794                 case S_NAN:
 795                         switch (infnanpos) {
 796                         case -1:        /* XXX kludge to deal with nan(...) */
 797                                 goto parsedone;
 798                         case 0:
 799                                 if (c != 'A' && c != 'a')
 800                                         goto parsedone;
 801                                 break;
 802                         case 1:
 803                                 if (c != 'N' && c != 'n')
 804                                         goto parsedone;
 805                                 else
 806                                         commit = p;
 807                                 break;
 808                         case 2:
 809                                 if (c != '(')
 810                                         goto parsedone;
 811                                 break;
 812                         default:
 813                                 if (c == ')') {
 814                                         commit = p;
 815                                         infnanpos = -2;
 816                                 } else if (!iswalnum(c) && c != '_')
 817                                         goto parsedone;
 818                                 break;
 819                         }
 820                         infnanpos++;
 821                         break;
 822                 case S_MAYBEHEX:
 823                         state = S_DIGITS;
 824                         if (c == 'X' || c == 'x') {
 825                                 ishex = 1;
 826                                 break;
 827                         } else {        /* we saw a '0', but no 'x' */
 828                                 gotmantdig = 1;
 829                                 goto reswitch;
 830                         }
 831                 case S_DIGITS:
 832                         if ((ishex && iswxdigit(c)) || iswdigit(c))
 833                                 gotmantdig = 1;
 834                         else {
 835                                 state = S_FRAC;
 836                                 if (c != decpt)
 837                                         goto reswitch;
 838                         }
 839                         if (gotmantdig)
 840                                 commit = p;
 841                         break;
 842                 case S_FRAC:
 843                         if (((c == 'E' || c == 'e') && !ishex) ||
 844                             ((c == 'P' || c == 'p') && ishex)) {
 845                                 if (!gotmantdig)
 846                                         goto parsedone;
 847                                 else
 848                                         state = S_EXP;
 849                         } else if ((ishex && iswxdigit(c)) || iswdigit(c)) {
 850                                 commit = p;
 851                                 gotmantdig = 1;
 852                         } else
 853                                 goto parsedone;
 854                         break;
 855                 case S_EXP:
 856                         state = S_EXPDIGITS;
 857                         if (c == '-' || c == '+')
 858                                 break;
 859                         else
 860                                 goto reswitch;
 861                 case S_EXPDIGITS:
 862                         if (iswdigit(c))
 863                                 commit = p;
 864                         else
 865                                 goto parsedone;
 866                         break;
 867                 default:
 868                         abort();
 869                 }
 870                 *p++ = c;
 871                 c = WEOF;
 872         }
 873
 874 parsedone:
 875         if (c != WEOF)
 876                 ungetwc(c, fp);
 877         while (commit < --p)
 878                 ungetwc(*p, fp);
 879         *++commit = '\0';
 880         return (commit - buf);
 881 }
 882 #endif