lib/libc/stdio/vfscanf.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
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 static char sccsid[] = "@(#)vfscanf.c   8.1 (Berkeley) 6/4/93";
  35 #endif /* LIBC_SCCS and not lint */
  36 #include <sys/cdefs.h>
  37 __FBSDID("$FreeBSD$");
  38
  39 #include "namespace.h"
  40 #include <ctype.h>
  41 #include <inttypes.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <stddef.h>
  45 #include <stdarg.h>
  46 #include <string.h>
  47 #include <wchar.h>
  48 #include <wctype.h>
  49 #include "un-namespace.h"
  50
  51 #include "collate.h"
  52 #include "libc_private.h"
  53 #include "local.h"
  54
  55 #ifndef NO_FLOATING_POINT
  56 #include <locale.h>
  57 #endif
  58
  59 #define BUF             513     /* Maximum length of numeric string. */
  60
  61 /*
  62  * Flags used during conversion.
  63  */
  64 #define LONG            0x01    /* l: long or double */
  65 #define LONGDBL         0x02    /* L: long double */
  66 #define SHORT           0x04    /* h: short */
  67 #define SUPPRESS        0x08    /* *: suppress assignment */
  68 #define POINTER         0x10    /* p: void * (as hex) */
  69 #define NOSKIP          0x20    /* [ or c: do not skip blanks */
  70 #define LONGLONG        0x400   /* ll: long long (+ deprecated q: quad) */
  71 #define INTMAXT         0x800   /* j: intmax_t */
  72 #define PTRDIFFT        0x1000  /* t: ptrdiff_t */
  73 #define SIZET           0x2000  /* z: size_t */
  74 #define SHORTSHORT      0x4000  /* hh: char */
  75 #define UNSIGNED        0x8000  /* %[oupxX] conversions */
  76
  77 /*
  78  * The following are used in integral conversions only:
  79  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
  80  */
  81 #define SIGNOK          0x40    /* +/- is (still) legal */
  82 #define NDIGITS         0x80    /* no digits detected */
  83 #define PFXOK           0x100   /* 0x prefix is (still) legal */
  84 #define NZDIGITS        0x200   /* no zero digits detected */
  85 #define HAVESIGN        0x10000 /* sign detected */
  86
  87 /*
  88  * Conversion types.
  89  */
  90 #define CT_CHAR         0       /* %c conversion */
  91 #define CT_CCL          1       /* %[...] conversion */
  92 #define CT_STRING       2       /* %s conversion */
  93 #define CT_INT          3       /* %[dioupxX] conversion */
  94 #define CT_FLOAT        4       /* %[efgEFG] conversion */
  95
  96 static const u_char *__sccl(char *, const u_char *);
  97 #ifndef NO_FLOATING_POINT
  98 static int parsefloat(FILE *, char *, char *);
  99 #endif
 100
 101 __weak_reference(__vfscanf, vfscanf);
 102
 103 /*
 104  * __vfscanf - MT-safe version
 105  */
 106 int
 107 __vfscanf(FILE *fp, char const *fmt0, va_list ap)
 108 {
 109         int ret;
 110
 111         FLOCKFILE(fp);
 112         ret = __svfscanf(fp, fmt0, ap);
 113         FUNLOCKFILE(fp);
 114         return (ret);
 115 }
 116
 117 /*
 118  * __svfscanf - non-MT-safe version of __vfscanf
 119  */
 120 int
 121 __svfscanf(FILE *fp, const char *fmt0, va_list ap)
 122 {
 123         const u_char *fmt = (const u_char *)fmt0;
 124         int c;                  /* character from format, or conversion */
 125         size_t width;           /* field width, or 0 */
 126         char *p;                /* points into all kinds of strings */
 127         int n;                  /* handy integer */
 128         int flags;              /* flags as defined above */
 129         char *p0;               /* saves original value of p when necessary */
 130         int nassigned;          /* number of fields assigned */
 131         int nconversions;       /* number of conversions */
 132         int nread;              /* number of characters consumed from fp */
 133         int base;               /* base argument to conversion function */
 134         char ccltab[256];       /* character class table for %[...] */
 135         char buf[BUF];          /* buffer for numeric and mb conversions */
 136         wchar_t *wcp;           /* handy wide character pointer */
 137         size_t nconv;           /* length of multibyte sequence converted */
 138         static const mbstate_t initial;
 139         mbstate_t mbs;
 140
 141         /* `basefix' is used to avoid `if' tests in the integer scanner */
 142         static short basefix[17] =
 143                 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
 144
 145         ORIENT(fp, -1);
 146
 147         nassigned = 0;
 148         nconversions = 0;
 149         nread = 0;
 150         for (;;) {
 151                 c = *fmt++;
 152                 if (c == 0)
 153                         return (nassigned);
 154                 if (isspace(c)) {
 155                         while ((fp->_r > 0 || __srefill(fp) == 0) && isspace(*fp->_p))
 156                                 nread++, fp->_r--, fp->_p++;
 157                         continue;
 158                 }
 159                 if (c != '%')
 160                         goto literal;
 161                 width = 0;
 162                 flags = 0;
 163                 /*
 164                  * switch on the format.  continue if done;
 165                  * break once format type is derived.
 166                  */
 167 again:          c = *fmt++;
 168                 switch (c) {
 169                 case '%':
 170 literal:
 171                         if (fp->_r <= 0 && __srefill(fp))
 172                                 goto input_failure;
 173                         if (*fp->_p != c)
 174                                 goto match_failure;
 175                         fp->_r--, fp->_p++;
 176                         nread++;
 177                         continue;
 178
 179                 case '*':
 180                         flags |= SUPPRESS;
 181                         goto again;
 182                 case 'j':
 183                         flags |= INTMAXT;
 184                         goto again;
 185                 case 'l':
 186                         if (flags & LONG) {
 187                                 flags &= ~LONG;
 188                                 flags |= LONGLONG;
 189                         } else
 190                                 flags |= LONG;
 191                         goto again;
 192                 case 'q':
 193                         flags |= LONGLONG;      /* not quite */
 194                         goto again;
 195                 case 't':
 196                         flags |= PTRDIFFT;
 197                         goto again;
 198                 case 'z':
 199                         flags |= SIZET;
 200                         goto again;
 201                 case 'L':
 202                         flags |= LONGDBL;
 203                         goto again;
 204                 case 'h':
 205                         if (flags & SHORT) {
 206                                 flags &= ~SHORT;
 207                                 flags |= SHORTSHORT;
 208                         } else
 209                                 flags |= SHORT;
 210                         goto again;
 211
 212                 case '0': case '1': case '2': case '3': case '4':
 213                 case '5': case '6': case '7': case '8': case '9':
 214                         width = width * 10 + c - '0';
 215                         goto again;
 216
 217                 /*
 218                  * Conversions.
 219                  */
 220                 case 'd':
 221                         c = CT_INT;
 222                         base = 10;
 223                         break;
 224
 225                 case 'i':
 226                         c = CT_INT;
 227                         base = 0;
 228                         break;
 229
 230                 case 'o':
 231                         c = CT_INT;
 232                         flags |= UNSIGNED;
 233                         base = 8;
 234                         break;
 235
 236                 case 'u':
 237                         c = CT_INT;
 238                         flags |= UNSIGNED;
 239                         base = 10;
 240                         break;
 241
 242                 case 'X':
 243                 case 'x':
 244                         flags |= PFXOK; /* enable 0x prefixing */
 245                         c = CT_INT;
 246                         flags |= UNSIGNED;
 247                         base = 16;
 248                         break;
 249
 250 #ifndef NO_FLOATING_POINT
 251                 case 'A': case 'E': case 'F': case 'G':
 252                 case 'a': case 'e': case 'f': case 'g':
 253                         c = CT_FLOAT;
 254                         break;
 255 #endif
 256
 257                 case 'S':
 258                         flags |= LONG;
 259                         /* FALLTHROUGH */
 260                 case 's':
 261                         c = CT_STRING;
 262                         break;
 263
 264                 case '[':
 265                         fmt = __sccl(ccltab, fmt);
 266                         flags |= NOSKIP;
 267                         c = CT_CCL;
 268                         break;
 269
 270                 case 'C':
 271                         flags |= LONG;
 272                         /* FALLTHROUGH */
 273                 case 'c':
 274                         flags |= NOSKIP;
 275                         c = CT_CHAR;
 276                         break;
 277
 278                 case 'p':       /* pointer format is like hex */
 279                         flags |= POINTER | PFXOK;
 280                         c = CT_INT;             /* assumes sizeof(uintmax_t) */
 281                         flags |= UNSIGNED;      /*      >= sizeof(uintptr_t) */
 282                         base = 16;
 283                         break;
 284
 285                 case 'n':
 286                         nconversions++;
 287                         if (flags & SUPPRESS)   /* ??? */
 288                                 continue;
 289                         if (flags & SHORTSHORT)
 290                                 *va_arg(ap, char *) = nread;
 291                         else if (flags & SHORT)
 292                                 *va_arg(ap, short *) = nread;
 293                         else if (flags & LONG)
 294                                 *va_arg(ap, long *) = nread;
 295                         else if (flags & LONGLONG)
 296                                 *va_arg(ap, long long *) = nread;
 297                         else if (flags & INTMAXT)
 298                                 *va_arg(ap, intmax_t *) = nread;
 299                         else if (flags & SIZET)
 300                                 *va_arg(ap, size_t *) = nread;
 301                         else if (flags & PTRDIFFT)
 302                                 *va_arg(ap, ptrdiff_t *) = nread;
 303                         else
 304                                 *va_arg(ap, int *) = nread;
 305                         continue;
 306
 307                 default:
 308                         goto match_failure;
 309
 310                 /*
 311                  * Disgusting backwards compatibility hack.     XXX
 312                  */
 313                 case '\0':      /* compat */
 314                         return (EOF);
 315                 }
 316
 317                 /*
 318                  * We have a conversion that requires input.
 319                  */
 320                 if (fp->_r <= 0 && __srefill(fp))
 321                         goto input_failure;
 322
 323                 /*
 324                  * Consume leading white space, except for formats
 325                  * that suppress this.
 326                  */
 327                 if ((flags & NOSKIP) == 0) {
 328                         while (isspace(*fp->_p)) {
 329                                 nread++;
 330                                 if (--fp->_r > 0)
 331                                         fp->_p++;
 332                                 else if (__srefill(fp))
 333                                         goto input_failure;
 334                         }
 335                         /*
 336                          * Note that there is at least one character in
 337                          * the buffer, so conversions that do not set NOSKIP
 338                          * ca no longer result in an input failure.
 339                          */
 340                 }
 341
 342                 /*
 343                  * Do the conversion.
 344                  */
 345                 switch (c) {
 346
 347                 case CT_CHAR:
 348                         /* scan arbitrary characters (sets NOSKIP) */
 349                         if (width == 0)
 350                                 width = 1;
 351                         if (flags & LONG) {
 352                                 if ((flags & SUPPRESS) == 0)
 353                                         wcp = va_arg(ap, wchar_t *);
 354                                 else
 355                                         wcp = NULL;
 356                                 n = 0;
 357                                 while (width != 0) {
 358                                         if (n == MB_CUR_MAX) {
 359                                                 fp->_flags |= __SERR;
 360                                                 goto input_failure;
 361                                         }
 362                                         buf[n++] = *fp->_p;
 363                                         fp->_p++;
 364                                         fp->_r--;
 365                                         mbs = initial;
 366                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 367                                         if (nconv == (size_t)-1) {
 368                                                 fp->_flags |= __SERR;
 369                                                 goto input_failure;
 370                                         }
 371                                         if (nconv == 0 && !(flags & SUPPRESS))
 372                                                 *wcp = L'\0';
 373                                         if (nconv != (size_t)-2) {
 374                                                 nread += n;
 375                                                 width--;
 376                                                 if (!(flags & SUPPRESS))
 377                                                         wcp++;
 378                                                 n = 0;
 379                                         }
 380                                         if (fp->_r <= 0 && __srefill(fp)) {
 381                                                 if (n != 0) {
 382                                                         fp->_flags |= __SERR;
 383                                                         goto input_failure;
 384                                                 }
 385                                                 break;
 386                                         }
 387                                 }
 388                                 if (!(flags & SUPPRESS))
 389                                         nassigned++;
 390                         } else if (flags & SUPPRESS) {
 391                                 size_t sum = 0;
 392                                 for (;;) {
 393                                         if ((n = fp->_r) < width) {
 394                                                 sum += n;
 395                                                 width -= n;
 396                                                 fp->_p += n;
 397                                                 if (__srefill(fp)) {
 398                                                         if (sum == 0)
 399                                                             goto input_failure;
 400                                                         break;
 401                                                 }
 402                                         } else {
 403                                                 sum += width;
 404                                                 fp->_r -= width;
 405                                                 fp->_p += width;
 406                                                 break;
 407                                         }
 408                                 }
 409                                 nread += sum;
 410                         } else {
 411                                 size_t r = __fread((void *)va_arg(ap, char *), 1,
 412                                     width, fp);
 413
 414                                 if (r == 0)
 415                                         goto input_failure;
 416                                 nread += r;
 417                                 nassigned++;
 418                         }
 419                         nconversions++;
 420                         break;
 421
 422                 case CT_CCL:
 423                         /* scan a (nonempty) character class (sets NOSKIP) */
 424                         if (width == 0)
 425                                 width = (size_t)~0;     /* `infinity' */
 426                         /* take only those things in the class */
 427                         if (flags & LONG) {
 428                                 wchar_t twc;
 429                                 int nchars;
 430
 431                                 if ((flags & SUPPRESS) == 0)
 432                                         wcp = va_arg(ap, wchar_t *);
 433                                 else
 434                                         wcp = &twc;
 435                                 n = 0;
 436                                 nchars = 0;
 437                                 while (width != 0) {
 438                                         if (n == MB_CUR_MAX) {
 439                                                 fp->_flags |= __SERR;
 440                                                 goto input_failure;
 441                                         }
 442                                         buf[n++] = *fp->_p;
 443                                         fp->_p++;
 444                                         fp->_r--;
 445                                         mbs = initial;
 446                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 447                                         if (nconv == (size_t)-1) {
 448                                                 fp->_flags |= __SERR;
 449                                                 goto input_failure;
 450                                         }
 451                                         if (nconv == 0)
 452                                                 *wcp = L'\0';
 453                                         if (nconv != (size_t)-2) {
 454                                                 if (wctob(*wcp) != EOF &&
 455                                                     !ccltab[wctob(*wcp)]) {
 456                                                         while (n != 0) {
 457                                                                 n--;
 458                                                                 __ungetc(buf[n],
 459                                                                     fp);
 460                                                         }
 461                                                         break;
 462                                                 }
 463                                                 nread += n;
 464                                                 width--;
 465                                                 if (!(flags & SUPPRESS))
 466                                                         wcp++;
 467                                                 nchars++;
 468                                                 n = 0;
 469                                         }
 470                                         if (fp->_r <= 0 && __srefill(fp)) {
 471                                                 if (n != 0) {
 472                                                         fp->_flags |= __SERR;
 473                                                         goto input_failure;
 474                                                 }
 475                                                 break;
 476                                         }
 477                                 }
 478                                 if (n != 0) {
 479                                         fp->_flags |= __SERR;
 480                                         goto input_failure;
 481                                 }
 482                                 n = nchars;
 483                                 if (n == 0)
 484                                         goto match_failure;
 485                                 if (!(flags & SUPPRESS)) {
 486                                         *wcp = L'\0';
 487                                         nassigned++;
 488                                 }
 489                         } else if (flags & SUPPRESS) {
 490                                 n = 0;
 491                                 while (ccltab[*fp->_p]) {
 492                                         n++, fp->_r--, fp->_p++;
 493                                         if (--width == 0)
 494                                                 break;
 495                                         if (fp->_r <= 0 && __srefill(fp)) {
 496                                                 if (n == 0)
 497                                                         goto input_failure;
 498                                                 break;
 499                                         }
 500                                 }
 501                                 if (n == 0)
 502                                         goto match_failure;
 503                         } else {
 504                                 p0 = p = va_arg(ap, char *);
 505                                 while (ccltab[*fp->_p]) {
 506                                         fp->_r--;
 507                                         *p++ = *fp->_p++;
 508                                         if (--width == 0)
 509                                                 break;
 510                                         if (fp->_r <= 0 && __srefill(fp)) {
 511                                                 if (p == p0)
 512                                                         goto input_failure;
 513                                                 break;
 514                                         }
 515                                 }
 516                                 n = p - p0;
 517                                 if (n == 0)
 518                                         goto match_failure;
 519                                 *p = 0;
 520                                 nassigned++;
 521                         }
 522                         nread += n;
 523                         nconversions++;
 524                         break;
 525
 526                 case CT_STRING:
 527                         /* like CCL, but zero-length string OK, & no NOSKIP */
 528                         if (width == 0)
 529                                 width = (size_t)~0;
 530                         if (flags & LONG) {
 531                                 wchar_t twc;
 532
 533                                 if ((flags & SUPPRESS) == 0)
 534                                         wcp = va_arg(ap, wchar_t *);
 535                                 else
 536                                         wcp = &twc;
 537                                 n = 0;
 538                                 while (!isspace(*fp->_p) && width != 0) {
 539                                         if (n == MB_CUR_MAX) {
 540                                                 fp->_flags |= __SERR;
 541                                                 goto input_failure;
 542                                         }
 543                                         buf[n++] = *fp->_p;
 544                                         fp->_p++;
 545                                         fp->_r--;
 546                                         mbs = initial;
 547                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 548                                         if (nconv == (size_t)-1) {
 549                                                 fp->_flags |= __SERR;
 550                                                 goto input_failure;
 551                                         }
 552                                         if (nconv == 0)
 553                                                 *wcp = L'\0';
 554                                         if (nconv != (size_t)-2) {
 555                                                 if (iswspace(*wcp)) {
 556                                                         while (n != 0) {
 557                                                                 n--;
 558                                                                 __ungetc(buf[n],
 559                                                                     fp);
 560                                                         }
 561                                                         break;
 562                                                 }
 563                                                 nread += n;
 564                                                 width--;
 565                                                 if (!(flags & SUPPRESS))
 566                                                         wcp++;
 567                                                 n = 0;
 568                                         }
 569                                         if (fp->_r <= 0 && __srefill(fp)) {
 570                                                 if (n != 0) {
 571                                                         fp->_flags |= __SERR;
 572                                                         goto input_failure;
 573                                                 }
 574                                                 break;
 575                                         }
 576                                 }
 577                                 if (!(flags & SUPPRESS)) {
 578                                         *wcp = L'\0';
 579                                         nassigned++;
 580                                 }
 581                         } else if (flags & SUPPRESS) {
 582                                 n = 0;
 583                                 while (!isspace(*fp->_p)) {
 584                                         n++, fp->_r--, fp->_p++;
 585                                         if (--width == 0)
 586                                                 break;
 587                                         if (fp->_r <= 0 && __srefill(fp))
 588                                                 break;
 589                                 }
 590                                 nread += n;
 591                         } else {
 592                                 p0 = p = va_arg(ap, char *);
 593                                 while (!isspace(*fp->_p)) {
 594                                         fp->_r--;
 595                                         *p++ = *fp->_p++;
 596                                         if (--width == 0)
 597                                                 break;
 598                                         if (fp->_r <= 0 && __srefill(fp))
 599                                                 break;
 600                                 }
 601                                 *p = 0;
 602                                 nread += p - p0;
 603                                 nassigned++;
 604                         }
 605                         nconversions++;
 606                         continue;
 607
 608                 case CT_INT:
 609                         /* scan an integer as if by the conversion function */
 610 #ifdef hardway
 611                         if (width == 0 || width > sizeof(buf) - 1)
 612                                 width = sizeof(buf) - 1;
 613 #else
 614                         /* size_t is unsigned, hence this optimisation */
 615                         if (--width > sizeof(buf) - 2)
 616                                 width = sizeof(buf) - 2;
 617                         width++;
 618 #endif
 619                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 620                         for (p = buf; width; width--) {
 621                                 c = *fp->_p;
 622                                 /*
 623                                  * Switch on the character; `goto ok'
 624                                  * if we accept it as a part of number.
 625                                  */
 626                                 switch (c) {
 627
 628                                 /*
 629                                  * The digit 0 is always legal, but is
 630                                  * special.  For %i conversions, if no
 631                                  * digits (zero or nonzero) have been
 632                                  * scanned (only signs), we will have
 633                                  * base==0.  In that case, we should set
 634                                  * it to 8 and enable 0x prefixing.
 635                                  * Also, if we have not scanned zero digits
 636                                  * before this, do not turn off prefixing
 637                                  * (someone else will turn it off if we
 638                                  * have scanned any nonzero digits).
 639                                  */
 640                                 case '0':
 641                                         if (base == 0) {
 642                                                 base = 8;
 643                                                 flags |= PFXOK;
 644                                         }
 645                                         if (flags & NZDIGITS)
 646                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 647                                         else
 648                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 649                                         goto ok;
 650
 651                                 /* 1 through 7 always legal */
 652                                 case '1': case '2': case '3':
 653                                 case '4': case '5': case '6': case '7':
 654                                         base = basefix[base];
 655                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 656                                         goto ok;
 657
 658                                 /* digits 8 and 9 ok iff decimal or hex */
 659                                 case '8': case '9':
 660                                         base = basefix[base];
 661                                         if (base <= 8)
 662                                                 break;  /* not legal here */
 663                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 664                                         goto ok;
 665
 666                                 /* letters ok iff hex */
 667                                 case 'A': case 'B': case 'C':
 668                                 case 'D': case 'E': case 'F':
 669                                 case 'a': case 'b': case 'c':
 670                                 case 'd': case 'e': case 'f':
 671                                         /* no need to fix base here */
 672                                         if (base <= 10)
 673                                                 break;  /* not legal here */
 674                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 675                                         goto ok;
 676
 677                                 /* sign ok only as first character */
 678                                 case '+': case '-':
 679                                         if (flags & SIGNOK) {
 680                                                 flags &= ~SIGNOK;
 681                                                 flags |= HAVESIGN;
 682                                                 goto ok;
 683                                         }
 684                                         break;
 685
 686                                 /*
 687                                  * x ok iff flag still set & 2nd char (or
 688                                  * 3rd char if we have a sign).
 689                                  */
 690                                 case 'x': case 'X':
 691                                         if (flags & PFXOK && p ==
 692                                             buf + 1 + !!(flags & HAVESIGN)) {
 693                                                 base = 16;      /* if %i */
 694                                                 flags &= ~PFXOK;
 695                                                 goto ok;
 696                                         }
 697                                         break;
 698                                 }
 699
 700                                 /*
 701                                  * If we got here, c is not a legal character
 702                                  * for a number.  Stop accumulating digits.
 703                                  */
 704                                 break;
 705                 ok:
 706                                 /*
 707                                  * c is legal: store it and look at the next.
 708                                  */
 709                                 *p++ = c;
 710                                 if (--fp->_r > 0)
 711                                         fp->_p++;
 712                                 else if (__srefill(fp))
 713                                         break;          /* EOF */
 714                         }
 715                         /*
 716                          * If we had only a sign, it is no good; push
 717                          * back the sign.  If the number ends in `x',
 718                          * it was [sign] '0' 'x', so push back the x
 719                          * and treat it as [sign] '0'.
 720                          */
 721                         if (flags & NDIGITS) {
 722                                 if (p > buf)
 723                                         (void) __ungetc(*(u_char *)--p, fp);
 724                                 goto match_failure;
 725                         }
 726                         c = ((u_char *)p)[-1];
 727                         if (c == 'x' || c == 'X') {
 728                                 --p;
 729                                 (void) __ungetc(c, fp);
 730                         }
 731                         if ((flags & SUPPRESS) == 0) {
 732                                 uintmax_t res;
 733
 734                                 *p = 0;
 735                                 if ((flags & UNSIGNED) == 0)
 736                                     res = strtoimax(buf, (char **)NULL, base);
 737                                 else
 738                                     res = strtoumax(buf, (char **)NULL, base);
 739                                 if (flags & POINTER)
 740                                         *va_arg(ap, void **) =
 741                                                         (void *)(uintptr_t)res;
 742                                 else if (flags & SHORTSHORT)
 743                                         *va_arg(ap, char *) = res;
 744                                 else if (flags & SHORT)
 745                                         *va_arg(ap, short *) = res;
 746                                 else if (flags & LONG)
 747                                         *va_arg(ap, long *) = res;
 748                                 else if (flags & LONGLONG)
 749                                         *va_arg(ap, long long *) = res;
 750                                 else if (flags & INTMAXT)
 751                                         *va_arg(ap, intmax_t *) = res;
 752                                 else if (flags & PTRDIFFT)
 753                                         *va_arg(ap, ptrdiff_t *) = res;
 754                                 else if (flags & SIZET)
 755                                         *va_arg(ap, size_t *) = res;
 756                                 else
 757                                         *va_arg(ap, int *) = res;
 758                                 nassigned++;
 759                         }
 760                         nread += p - buf;
 761                         nconversions++;
 762                         break;
 763
 764 #ifndef NO_FLOATING_POINT
 765                 case CT_FLOAT:
 766                         /* scan a floating point number as if by strtod */
 767                         if (width == 0 || width > sizeof(buf) - 1)
 768                                 width = sizeof(buf) - 1;
 769                         if ((width = parsefloat(fp, buf, buf + width)) == 0)
 770                                 goto match_failure;
 771                         if ((flags & SUPPRESS) == 0) {
 772                                 if (flags & LONGDBL) {
 773                                         long double res = strtold(buf, &p);
 774                                         *va_arg(ap, long double *) = res;
 775                                 } else if (flags & LONG) {
 776                                         double res = strtod(buf, &p);
 777                                         *va_arg(ap, double *) = res;
 778                                 } else {
 779                                         float res = strtof(buf, &p);
 780                                         *va_arg(ap, float *) = res;
 781                                 }
 782                                 nassigned++;
 783                         }
 784                         nread += width;
 785                         nconversions++;
 786                         break;
 787 #endif /* !NO_FLOATING_POINT */
 788                 }
 789         }
 790 input_failure:
 791         return (nconversions != 0 ? nassigned : EOF);
 792 match_failure:
 793         return (nassigned);
 794 }
 795
 796 /*
 797  * Fill in the given table from the scanset at the given format
 798  * (just after `[').  Return a pointer to the character past the
 799  * closing `]'.  The table has a 1 wherever characters should be
 800  * considered part of the scanset.
 801  */
 802 static const u_char *
 803 __sccl(tab, fmt)
 804         char *tab;
 805         const u_char *fmt;
 806 {
 807         int c, n, v, i;
 808
 809         /* first `clear' the whole table */
 810         c = *fmt++;             /* first char hat => negated scanset */
 811         if (c == '^') {
 812                 v = 1;          /* default => accept */
 813                 c = *fmt++;     /* get new first char */
 814         } else
 815                 v = 0;          /* default => reject */
 816
 817         /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
 818         (void) memset(tab, v, 256);
 819
 820         if (c == 0)
 821                 return (fmt - 1);/* format ended before closing ] */
 822
 823         /*
 824          * Now set the entries corresponding to the actual scanset
 825          * to the opposite of the above.
 826          *
 827          * The first character may be ']' (or '-') without being special;
 828          * the last character may be '-'.
 829          */
 830         v = 1 - v;
 831         for (;;) {
 832                 tab[c] = v;             /* take character c */
 833 doswitch:
 834                 n = *fmt++;             /* and examine the next */
 835                 switch (n) {
 836
 837                 case 0:                 /* format ended too soon */
 838                         return (fmt - 1);
 839
 840                 case '-':
 841                         /*
 842                          * A scanset of the form
 843                          *      [01+-]
 844                          * is defined as `the digit 0, the digit 1,
 845                          * the character +, the character -', but
 846                          * the effect of a scanset such as
 847                          *      [a-zA-Z0-9]
 848                          * is implementation defined.  The V7 Unix
 849                          * scanf treats `a-z' as `the letters a through
 850                          * z', but treats `a-a' as `the letter a, the
 851                          * character -, and the letter a'.
 852                          *
 853                          * For compatibility, the `-' is not considerd
 854                          * to define a range if the character following
 855                          * it is either a close bracket (required by ANSI)
 856                          * or is not numerically greater than the character
 857                          * we just stored in the table (c).
 858                          */
 859                         n = *fmt;
 860                         if (n == ']'
 861                             || (__collate_load_error ? n < c :
 862                                 __collate_range_cmp (n, c) < 0
 863                                )
 864                            ) {
 865                                 c = '-';
 866                                 break;  /* resume the for(;;) */
 867                         }
 868                         fmt++;
 869                         /* fill in the range */
 870                         if (__collate_load_error) {
 871                                 do {
 872                                         tab[++c] = v;
 873                                 } while (c < n);
 874                         } else {
 875                                 for (i = 0; i < 256; i ++)
 876                                         if (   __collate_range_cmp (c, i) < 0
 877                                             && __collate_range_cmp (i, n) <= 0
 878                                            )
 879                                                 tab[i] = v;
 880                         }
 881 #if 1   /* XXX another disgusting compatibility hack */
 882                         c = n;
 883                         /*
 884                          * Alas, the V7 Unix scanf also treats formats
 885                          * such as [a-c-e] as `the letters a through e'.
 886                          * This too is permitted by the standard....
 887                          */
 888                         goto doswitch;
 889 #else
 890                         c = *fmt++;
 891                         if (c == 0)
 892                                 return (fmt - 1);
 893                         if (c == ']')
 894                                 return (fmt);
 895 #endif
 896                         break;
 897
 898                 case ']':               /* end of scanset */
 899                         return (fmt);
 900
 901                 default:                /* just another character */
 902                         c = n;
 903                         break;
 904                 }
 905         }
 906         /* NOTREACHED */
 907 }
 908
 909 #ifndef NO_FLOATING_POINT
 910 static int
 911 parsefloat(FILE *fp, char *buf, char *end)
 912 {
 913         char *commit, *p;
 914         int infnanpos = 0, decptpos = 0;
 915         enum {
 916                 S_START, S_GOTSIGN, S_INF, S_NAN, S_DONE, S_MAYBEHEX,
 917                 S_DIGITS, S_DECPT, S_FRAC, S_EXP, S_EXPDIGITS
 918         } state = S_START;
 919         unsigned char c;
 920         const char *decpt = localeconv()->decimal_point;
 921         _Bool gotmantdig = 0, ishex = 0;
 922
 923         /*
 924          * We set commit = p whenever the string we have read so far
 925          * constitutes a valid representation of a floating point
 926          * number by itself.  At some point, the parse will complete
 927          * or fail, and we will ungetc() back to the last commit point.
 928          * To ensure that the file offset gets updated properly, it is
 929          * always necessary to read at least one character that doesn't
 930          * match; thus, we can't short-circuit "infinity" or "nan(...)".
 931          */
 932         commit = buf - 1;
 933         for (p = buf; p < end; ) {
 934                 c = *fp->_p;
 935 reswitch:
 936                 switch (state) {
 937                 case S_START:
 938                         state = S_GOTSIGN;
 939                         if (c == '-' || c == '+')
 940                                 break;
 941                         else
 942                                 goto reswitch;
 943                 case S_GOTSIGN:
 944                         switch (c) {
 945                         case '0':
 946                                 state = S_MAYBEHEX;
 947                                 commit = p;
 948                                 break;
 949                         case 'I':
 950                         case 'i':
 951                                 state = S_INF;
 952                                 break;
 953                         case 'N':
 954                         case 'n':
 955                                 state = S_NAN;
 956                                 break;
 957                         default:
 958                                 state = S_DIGITS;
 959                                 goto reswitch;
 960                         }
 961                         break;
 962                 case S_INF:
 963                         if (infnanpos > 6 ||
 964                             (c != "nfinity"[infnanpos] &&
 965                              c != "NFINITY"[infnanpos]))
 966                                 goto parsedone;
 967                         if (infnanpos == 1 || infnanpos == 6)
 968                                 commit = p;     /* inf or infinity */
 969                         infnanpos++;
 970                         break;
 971                 case S_NAN:
 972                         switch (infnanpos) {
 973                         case 0:
 974                                 if (c != 'A' && c != 'a')
 975                                         goto parsedone;
 976                                 break;
 977                         case 1:
 978                                 if (c != 'N' && c != 'n')
 979                                         goto parsedone;
 980                                 else
 981                                         commit = p;
 982                                 break;
 983                         case 2:
 984                                 if (c != '(')
 985                                         goto parsedone;
 986                                 break;
 987                         default:
 988                                 if (c == ')') {
 989                                         commit = p;
 990                                         state = S_DONE;
 991                                 } else if (!isalnum(c) && c != '_')
 992                                         goto parsedone;
 993                                 break;
 994                         }
 995                         infnanpos++;
 996                         break;
 997                 case S_DONE:
 998                         goto parsedone;
 999                 case S_MAYBEHEX:
1000                         state = S_DIGITS;
1001                         if (c == 'X' || c == 'x') {
1002                                 ishex = 1;
1003                                 break;
1004                         } else {        /* we saw a '0', but no 'x' */
1005                                 gotmantdig = 1;
1006                                 goto reswitch;
1007                         }
1008                 case S_DIGITS:
1009                         if ((ishex && isxdigit(c)) || isdigit(c)) {
1010                                 gotmantdig = 1;
1011                                 commit = p;
1012                                 break;
1013                         } else {
1014                                 state = S_DECPT;
1015                                 goto reswitch;
1016                         }
1017                 case S_DECPT:
1018                         if (c == decpt[decptpos]) {
1019                                 if (decpt[++decptpos] == '\0') {
1020                                         /* We read the complete decpt seq. */
1021                                         state = S_FRAC;
1022                                         if (gotmantdig)
1023                                                 commit = p;
1024                                 }
1025                                 break;
1026                         } else if (!decptpos) {
1027                                 /* We didn't read any decpt characters. */
1028                                 state = S_FRAC;
1029                                 goto reswitch;
1030                         } else {
1031                                 /*
1032                                  * We read part of a multibyte decimal point,
1033                                  * but the rest is invalid, so bail.
1034                                  */
1035                                 goto parsedone;
1036                         }
1037                 case S_FRAC:
1038                         if (((c == 'E' || c == 'e') && !ishex) ||
1039                             ((c == 'P' || c == 'p') && ishex)) {
1040                                 if (!gotmantdig)
1041                                         goto parsedone;
1042                                 else
1043                                         state = S_EXP;
1044                         } else if ((ishex && isxdigit(c)) || isdigit(c)) {
1045                                 commit = p;
1046                                 gotmantdig = 1;
1047                         } else
1048                                 goto parsedone;
1049                         break;
1050                 case S_EXP:
1051                         state = S_EXPDIGITS;
1052                         if (c == '-' || c == '+')
1053                                 break;
1054                         else
1055                                 goto reswitch;
1056                 case S_EXPDIGITS:
1057                         if (isdigit(c))
1058                                 commit = p;
1059                         else
1060                                 goto parsedone;
1061                         break;
1062                 default:
1063                         abort();
1064                 }
1065                 *p++ = c;
1066                 if (--fp->_r > 0)
1067                         fp->_p++;
1068                 else if (__srefill(fp))
1069                         break;  /* EOF */
1070         }
1071
1072 parsedone:
1073         while (commit < --p)
1074                 __ungetc(*(u_char *)p, fp);
1075         *++commit = '\0';
1076         return (commit - buf);
1077 }
1078 #endif