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  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #if defined(LIBC_SCCS) && !defined(lint)
  38 static char sccsid[] = "@(#)vfscanf.c   8.1 (Berkeley) 6/4/93";
  39 #endif /* LIBC_SCCS and not lint */
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 #include "namespace.h"
  44 #include <ctype.h>
  45 #include <inttypes.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <stddef.h>
  49 #include <stdarg.h>
  50 #include <string.h>
  51 #include <wchar.h>
  52 #include <wctype.h>
  53 #include "un-namespace.h"
  54
  55 #include "collate.h"
  56 #include "libc_private.h"
  57 #include "local.h"
  58
  59 #ifndef NO_FLOATING_POINT
  60 #include <locale.h>
  61 #endif
  62
  63 #define BUF             513     /* Maximum length of numeric string. */
  64
  65 /*
  66  * Flags used during conversion.
  67  */
  68 #define LONG            0x01    /* l: long or double */
  69 #define LONGDBL         0x02    /* L: long double */
  70 #define SHORT           0x04    /* h: short */
  71 #define SUPPRESS        0x08    /* *: suppress assignment */
  72 #define POINTER         0x10    /* p: void * (as hex) */
  73 #define NOSKIP          0x20    /* [ or c: do not skip blanks */
  74 #define LONGLONG        0x400   /* ll: long long (+ deprecated q: quad) */
  75 #define INTMAXT         0x800   /* j: intmax_t */
  76 #define PTRDIFFT        0x1000  /* t: ptrdiff_t */
  77 #define SIZET           0x2000  /* z: size_t */
  78 #define SHORTSHORT      0x4000  /* hh: char */
  79 #define UNSIGNED        0x8000  /* %[oupxX] conversions */
  80
  81 /*
  82  * The following are used in integral conversions only:
  83  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
  84  */
  85 #define SIGNOK          0x40    /* +/- is (still) legal */
  86 #define NDIGITS         0x80    /* no digits detected */
  87 #define PFXOK           0x100   /* 0x prefix is (still) legal */
  88 #define NZDIGITS        0x200   /* no zero digits detected */
  89 #define HAVESIGN        0x10000 /* sign detected */
  90
  91 /*
  92  * Conversion types.
  93  */
  94 #define CT_CHAR         0       /* %c conversion */
  95 #define CT_CCL          1       /* %[...] conversion */
  96 #define CT_STRING       2       /* %s conversion */
  97 #define CT_INT          3       /* %[dioupxX] conversion */
  98 #define CT_FLOAT        4       /* %[efgEFG] conversion */
  99
 100 static const u_char *__sccl(char *, const u_char *);
 101 #ifndef NO_FLOATING_POINT
 102 static int parsefloat(FILE *, char *, char *);
 103 #endif
 104
 105 int __scanfdebug = 0;
 106
 107 __weak_reference(__vfscanf, vfscanf);
 108
 109 /*
 110  * __vfscanf - MT-safe version
 111  */
 112 int
 113 __vfscanf(FILE *fp, char const *fmt0, va_list ap)
 114 {
 115         int ret;
 116
 117         FLOCKFILE(fp);
 118         ret = __svfscanf(fp, fmt0, ap);
 119         FUNLOCKFILE(fp);
 120         return (ret);
 121 }
 122
 123 /*
 124  * __svfscanf - non-MT-safe version of __vfscanf
 125  */
 126 int
 127 __svfscanf(FILE *fp, const char *fmt0, va_list ap)
 128 {
 129         const u_char *fmt = (const u_char *)fmt0;
 130         int c;                  /* character from format, or conversion */
 131         size_t width;           /* field width, or 0 */
 132         char *p;                /* points into all kinds of strings */
 133         int n;                  /* handy integer */
 134         int flags;              /* flags as defined above */
 135         char *p0;               /* saves original value of p when necessary */
 136         int nassigned;          /* number of fields assigned */
 137         int nconversions;       /* number of conversions */
 138         int nread;              /* number of characters consumed from fp */
 139         int base;               /* base argument to conversion function */
 140         char ccltab[256];       /* character class table for %[...] */
 141         char buf[BUF];          /* buffer for numeric and mb conversions */
 142         wchar_t *wcp;           /* handy wide character pointer */
 143         size_t nconv;           /* length of multibyte sequence converted */
 144         static const mbstate_t initial;
 145         mbstate_t mbs;
 146
 147         /* `basefix' is used to avoid `if' tests in the integer scanner */
 148         static short basefix[17] =
 149                 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
 150
 151         ORIENT(fp, -1);
 152
 153         nassigned = 0;
 154         nconversions = 0;
 155         nread = 0;
 156         for (;;) {
 157                 c = *fmt++;
 158                 if (c == 0)
 159                         return (nassigned);
 160                 if (isspace(c)) {
 161                         while ((fp->_r > 0 || __srefill(fp) == 0) && isspace(*fp->_p))
 162                                 nread++, fp->_r--, fp->_p++;
 163                         continue;
 164                 }
 165                 if (c != '%')
 166                         goto literal;
 167                 width = 0;
 168                 flags = 0;
 169                 /*
 170                  * switch on the format.  continue if done;
 171                  * break once format type is derived.
 172                  */
 173 again:          c = *fmt++;
 174                 switch (c) {
 175                 case '%':
 176 literal:
 177                         if (fp->_r <= 0 && __srefill(fp))
 178                                 goto input_failure;
 179                         if (*fp->_p != c)
 180                                 goto match_failure;
 181                         fp->_r--, fp->_p++;
 182                         nread++;
 183                         continue;
 184
 185                 case '*':
 186                         flags |= SUPPRESS;
 187                         goto again;
 188                 case 'j':
 189                         flags |= INTMAXT;
 190                         goto again;
 191                 case 'l':
 192                         if (flags & LONG) {
 193                                 flags &= ~LONG;
 194                                 flags |= LONGLONG;
 195                         } else
 196                                 flags |= LONG;
 197                         goto again;
 198                 case 'q':
 199                         flags |= LONGLONG;      /* not quite */
 200                         goto again;
 201                 case 't':
 202                         flags |= PTRDIFFT;
 203                         goto again;
 204                 case 'z':
 205                         flags |= SIZET;
 206                         goto again;
 207                 case 'L':
 208                         flags |= LONGDBL;
 209                         goto again;
 210                 case 'h':
 211                         if (flags & SHORT) {
 212                                 flags &= ~SHORT;
 213                                 flags |= SHORTSHORT;
 214                         } else
 215                                 flags |= SHORT;
 216                         goto again;
 217
 218                 case '0': case '1': case '2': case '3': case '4':
 219                 case '5': case '6': case '7': case '8': case '9':
 220                         width = width * 10 + c - '0';
 221                         goto again;
 222
 223                 /*
 224                  * Conversions.
 225                  */
 226                 case 'd':
 227                         c = CT_INT;
 228                         base = 10;
 229                         break;
 230
 231                 case 'i':
 232                         c = CT_INT;
 233                         base = 0;
 234                         break;
 235
 236                 case 'o':
 237                         c = CT_INT;
 238                         flags |= UNSIGNED;
 239                         base = 8;
 240                         break;
 241
 242                 case 'u':
 243                         c = CT_INT;
 244                         flags |= UNSIGNED;
 245                         base = 10;
 246                         break;
 247
 248                 case 'X':
 249                 case 'x':
 250                         flags |= PFXOK; /* enable 0x prefixing */
 251                         c = CT_INT;
 252                         flags |= UNSIGNED;
 253                         base = 16;
 254                         break;
 255
 256 #ifndef NO_FLOATING_POINT
 257                 case 'A': case 'E': case 'F': case 'G':
 258                 case 'a': case 'e': case 'f': case 'g':
 259                         c = CT_FLOAT;
 260                         break;
 261 #endif
 262
 263                 case 'S':
 264                         flags |= LONG;
 265                         /* FALLTHROUGH */
 266                 case 's':
 267                         c = CT_STRING;
 268                         break;
 269
 270                 case '[':
 271                         fmt = __sccl(ccltab, fmt);
 272                         flags |= NOSKIP;
 273                         c = CT_CCL;
 274                         break;
 275
 276                 case 'C':
 277                         flags |= LONG;
 278                         /* FALLTHROUGH */
 279                 case 'c':
 280                         flags |= NOSKIP;
 281                         c = CT_CHAR;
 282                         break;
 283
 284                 case 'p':       /* pointer format is like hex */
 285                         flags |= POINTER | PFXOK;
 286                         c = CT_INT;             /* assumes sizeof(uintmax_t) */
 287                         flags |= UNSIGNED;      /*      >= sizeof(uintptr_t) */
 288                         base = 16;
 289                         break;
 290
 291                 case 'n':
 292                         nconversions++;
 293                         if (flags & SUPPRESS)   /* ??? */
 294                                 continue;
 295                         if (flags & SHORTSHORT)
 296                                 *va_arg(ap, char *) = nread;
 297                         else if (flags & SHORT)
 298                                 *va_arg(ap, short *) = nread;
 299                         else if (flags & LONG)
 300                                 *va_arg(ap, long *) = nread;
 301                         else if (flags & LONGLONG)
 302                                 *va_arg(ap, long long *) = nread;
 303                         else if (flags & INTMAXT)
 304                                 *va_arg(ap, intmax_t *) = nread;
 305                         else if (flags & SIZET)
 306                                 *va_arg(ap, size_t *) = nread;
 307                         else if (flags & PTRDIFFT)
 308                                 *va_arg(ap, ptrdiff_t *) = nread;
 309                         else
 310                                 *va_arg(ap, int *) = nread;
 311                         continue;
 312
 313                 default:
 314                         goto match_failure;
 315
 316                 /*
 317                  * Disgusting backwards compatibility hack.     XXX
 318                  */
 319                 case '\0':      /* compat */
 320                         return (EOF);
 321                 }
 322
 323                 /*
 324                  * We have a conversion that requires input.
 325                  */
 326                 if (fp->_r <= 0 && __srefill(fp))
 327                         goto input_failure;
 328
 329                 /*
 330                  * Consume leading white space, except for formats
 331                  * that suppress this.
 332                  */
 333                 if ((flags & NOSKIP) == 0) {
 334                         while (isspace(*fp->_p)) {
 335                                 nread++;
 336                                 if (--fp->_r > 0)
 337                                         fp->_p++;
 338                                 else if (__srefill(fp))
 339                                         goto input_failure;
 340                         }
 341                         /*
 342                          * Note that there is at least one character in
 343                          * the buffer, so conversions that do not set NOSKIP
 344                          * ca no longer result in an input failure.
 345                          */
 346                 }
 347
 348                 /*
 349                  * Do the conversion.
 350                  */
 351                 switch (c) {
 352
 353                 case CT_CHAR:
 354                         /* scan arbitrary characters (sets NOSKIP) */
 355                         if (width == 0)
 356                                 width = 1;
 357                         if (flags & LONG) {
 358                                 if ((flags & SUPPRESS) == 0)
 359                                         wcp = va_arg(ap, wchar_t *);
 360                                 else
 361                                         wcp = NULL;
 362                                 n = 0;
 363                                 while (width != 0) {
 364                                         if (n == MB_CUR_MAX) {
 365                                                 fp->_flags |= __SERR;
 366                                                 goto input_failure;
 367                                         }
 368                                         buf[n++] = *fp->_p;
 369                                         fp->_p++;
 370                                         fp->_r--;
 371                                         mbs = initial;
 372                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 373                                         if (nconv == (size_t)-1) {
 374                                                 fp->_flags |= __SERR;
 375                                                 goto input_failure;
 376                                         }
 377                                         if (nconv == 0 && !(flags & SUPPRESS))
 378                                                 *wcp = L'\0';
 379                                         if (nconv != (size_t)-2) {
 380                                                 nread += n;
 381                                                 width--;
 382                                                 if (!(flags & SUPPRESS))
 383                                                         wcp++;
 384                                                 n = 0;
 385                                         }
 386                                         if (fp->_r <= 0 && __srefill(fp)) {
 387                                                 if (n != 0) {
 388                                                         fp->_flags |= __SERR;
 389                                                         goto input_failure;
 390                                                 }
 391                                                 break;
 392                                         }
 393                                 }
 394                                 if (!(flags & SUPPRESS))
 395                                         nassigned++;
 396                         } else if (flags & SUPPRESS) {
 397                                 size_t sum = 0;
 398                                 for (;;) {
 399                                         if ((n = fp->_r) < width) {
 400                                                 sum += n;
 401                                                 width -= n;
 402                                                 fp->_p += n;
 403                                                 if (__srefill(fp)) {
 404                                                         if (sum == 0)
 405                                                             goto input_failure;
 406                                                         break;
 407                                                 }
 408                                         } else {
 409                                                 sum += width;
 410                                                 fp->_r -= width;
 411                                                 fp->_p += width;
 412                                                 break;
 413                                         }
 414                                 }
 415                                 nread += sum;
 416                         } else {
 417                                 size_t r = __fread((void *)va_arg(ap, char *), 1,
 418                                     width, fp);
 419
 420                                 if (r == 0)
 421                                         goto input_failure;
 422                                 nread += r;
 423                                 nassigned++;
 424                         }
 425                         nconversions++;
 426                         break;
 427
 428                 case CT_CCL:
 429                         /* scan a (nonempty) character class (sets NOSKIP) */
 430                         if (width == 0)
 431                                 width = (size_t)~0;     /* `infinity' */
 432                         /* take only those things in the class */
 433                         if (flags & LONG) {
 434                                 wchar_t twc;
 435                                 int nchars;
 436
 437                                 if ((flags & SUPPRESS) == 0)
 438                                         wcp = va_arg(ap, wchar_t *);
 439                                 else
 440                                         wcp = &twc;
 441                                 n = 0;
 442                                 nchars = 0;
 443                                 while (width != 0) {
 444                                         if (n == MB_CUR_MAX) {
 445                                                 fp->_flags |= __SERR;
 446                                                 goto input_failure;
 447                                         }
 448                                         buf[n++] = *fp->_p;
 449                                         fp->_p++;
 450                                         fp->_r--;
 451                                         mbs = initial;
 452                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 453                                         if (nconv == (size_t)-1) {
 454                                                 fp->_flags |= __SERR;
 455                                                 goto input_failure;
 456                                         }
 457                                         if (nconv == 0)
 458                                                 *wcp = L'\0';
 459                                         if (nconv != (size_t)-2) {
 460                                                 if (wctob(*wcp) != EOF &&
 461                                                     !ccltab[wctob(*wcp)]) {
 462                                                         while (n != 0) {
 463                                                                 n--;
 464                                                                 __ungetc(buf[n],
 465                                                                     fp);
 466                                                         }
 467                                                         break;
 468                                                 }
 469                                                 nread += n;
 470                                                 width--;
 471                                                 if (!(flags & SUPPRESS))
 472                                                         wcp++;
 473                                                 nchars++;
 474                                                 n = 0;
 475                                         }
 476                                         if (fp->_r <= 0 && __srefill(fp)) {
 477                                                 if (n != 0) {
 478                                                         fp->_flags |= __SERR;
 479                                                         goto input_failure;
 480                                                 }
 481                                                 break;
 482                                         }
 483                                 }
 484                                 if (n != 0) {
 485                                         fp->_flags |= __SERR;
 486                                         goto input_failure;
 487                                 }
 488                                 n = nchars;
 489                                 if (n == 0)
 490                                         goto match_failure;
 491                                 if (!(flags & SUPPRESS)) {
 492                                         *wcp = L'\0';
 493                                         nassigned++;
 494                                 }
 495                         } else if (flags & SUPPRESS) {
 496                                 n = 0;
 497                                 while (ccltab[*fp->_p]) {
 498                                         n++, fp->_r--, fp->_p++;
 499                                         if (--width == 0)
 500                                                 break;
 501                                         if (fp->_r <= 0 && __srefill(fp)) {
 502                                                 if (n == 0)
 503                                                         goto input_failure;
 504                                                 break;
 505                                         }
 506                                 }
 507                                 if (n == 0)
 508                                         goto match_failure;
 509                         } else {
 510                                 p0 = p = va_arg(ap, char *);
 511                                 while (ccltab[*fp->_p]) {
 512                                         fp->_r--;
 513                                         *p++ = *fp->_p++;
 514                                         if (--width == 0)
 515                                                 break;
 516                                         if (fp->_r <= 0 && __srefill(fp)) {
 517                                                 if (p == p0)
 518                                                         goto input_failure;
 519                                                 break;
 520                                         }
 521                                 }
 522                                 n = p - p0;
 523                                 if (n == 0)
 524                                         goto match_failure;
 525                                 *p = 0;
 526                                 nassigned++;
 527                         }
 528                         nread += n;
 529                         nconversions++;
 530                         break;
 531
 532                 case CT_STRING:
 533                         /* like CCL, but zero-length string OK, & no NOSKIP */
 534                         if (width == 0)
 535                                 width = (size_t)~0;
 536                         if (flags & LONG) {
 537                                 wchar_t twc;
 538
 539                                 if ((flags & SUPPRESS) == 0)
 540                                         wcp = va_arg(ap, wchar_t *);
 541                                 else
 542                                         wcp = &twc;
 543                                 n = 0;
 544                                 while (!isspace(*fp->_p) && width != 0) {
 545                                         if (n == MB_CUR_MAX) {
 546                                                 fp->_flags |= __SERR;
 547                                                 goto input_failure;
 548                                         }
 549                                         buf[n++] = *fp->_p;
 550                                         fp->_p++;
 551                                         fp->_r--;
 552                                         mbs = initial;
 553                                         nconv = mbrtowc(wcp, buf, n, &mbs);
 554                                         if (nconv == (size_t)-1) {
 555                                                 fp->_flags |= __SERR;
 556                                                 goto input_failure;
 557                                         }
 558                                         if (nconv == 0)
 559                                                 *wcp = L'\0';
 560                                         if (nconv != (size_t)-2) {
 561                                                 if (iswspace(*wcp)) {
 562                                                         while (n != 0) {
 563                                                                 n--;
 564                                                                 __ungetc(buf[n],
 565                                                                     fp);
 566                                                         }
 567                                                         break;
 568                                                 }
 569                                                 nread += n;
 570                                                 width--;
 571                                                 if (!(flags & SUPPRESS))
 572                                                         wcp++;
 573                                                 n = 0;
 574                                         }
 575                                         if (fp->_r <= 0 && __srefill(fp)) {
 576                                                 if (n != 0) {
 577                                                         fp->_flags |= __SERR;
 578                                                         goto input_failure;
 579                                                 }
 580                                                 break;
 581                                         }
 582                                 }
 583                                 if (!(flags & SUPPRESS)) {
 584                                         *wcp = L'\0';
 585                                         nassigned++;
 586                                 }
 587                         } else if (flags & SUPPRESS) {
 588                                 n = 0;
 589                                 while (!isspace(*fp->_p)) {
 590                                         n++, fp->_r--, fp->_p++;
 591                                         if (--width == 0)
 592                                                 break;
 593                                         if (fp->_r <= 0 && __srefill(fp))
 594                                                 break;
 595                                 }
 596                                 nread += n;
 597                         } else {
 598                                 p0 = p = va_arg(ap, char *);
 599                                 while (!isspace(*fp->_p)) {
 600                                         fp->_r--;
 601                                         *p++ = *fp->_p++;
 602                                         if (--width == 0)
 603                                                 break;
 604                                         if (fp->_r <= 0 && __srefill(fp))
 605                                                 break;
 606                                 }
 607                                 *p = 0;
 608                                 nread += p - p0;
 609                                 nassigned++;
 610                         }
 611                         nconversions++;
 612                         continue;
 613
 614                 case CT_INT:
 615                         /* scan an integer as if by the conversion function */
 616 #ifdef hardway
 617                         if (width == 0 || width > sizeof(buf) - 1)
 618                                 width = sizeof(buf) - 1;
 619 #else
 620                         /* size_t is unsigned, hence this optimisation */
 621                         if (--width > sizeof(buf) - 2)
 622                                 width = sizeof(buf) - 2;
 623                         width++;
 624 #endif
 625                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 626                         for (p = buf; width; width--) {
 627                                 c = *fp->_p;
 628                                 /*
 629                                  * Switch on the character; `goto ok'
 630                                  * if we accept it as a part of number.
 631                                  */
 632                                 switch (c) {
 633
 634                                 /*
 635                                  * The digit 0 is always legal, but is
 636                                  * special.  For %i conversions, if no
 637                                  * digits (zero or nonzero) have been
 638                                  * scanned (only signs), we will have
 639                                  * base==0.  In that case, we should set
 640                                  * it to 8 and enable 0x prefixing.
 641                                  * Also, if we have not scanned zero digits
 642                                  * before this, do not turn off prefixing
 643                                  * (someone else will turn it off if we
 644                                  * have scanned any nonzero digits).
 645                                  */
 646                                 case '0':
 647                                         if (base == 0) {
 648                                                 base = 8;
 649                                                 flags |= PFXOK;
 650                                         }
 651                                         if (flags & NZDIGITS)
 652                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 653                                         else
 654                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 655                                         goto ok;
 656
 657                                 /* 1 through 7 always legal */
 658                                 case '1': case '2': case '3':
 659                                 case '4': case '5': case '6': case '7':
 660                                         base = basefix[base];
 661                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 662                                         goto ok;
 663
 664                                 /* digits 8 and 9 ok iff decimal or hex */
 665                                 case '8': case '9':
 666                                         base = basefix[base];
 667                                         if (base <= 8)
 668                                                 break;  /* not legal here */
 669                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 670                                         goto ok;
 671
 672                                 /* letters ok iff hex */
 673                                 case 'A': case 'B': case 'C':
 674                                 case 'D': case 'E': case 'F':
 675                                 case 'a': case 'b': case 'c':
 676                                 case 'd': case 'e': case 'f':
 677                                         /* no need to fix base here */
 678                                         if (base <= 10)
 679                                                 break;  /* not legal here */
 680                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 681                                         goto ok;
 682
 683                                 /* sign ok only as first character */
 684                                 case '+': case '-':
 685                                         if (flags & SIGNOK) {
 686                                                 flags &= ~SIGNOK;
 687                                                 flags |= HAVESIGN;
 688                                                 goto ok;
 689                                         }
 690                                         break;
 691
 692                                 /*
 693                                  * x ok iff flag still set & 2nd char (or
 694                                  * 3rd char if we have a sign).
 695                                  */
 696                                 case 'x': case 'X':
 697                                         if (flags & PFXOK && p ==
 698                                             buf + 1 + !!(flags & HAVESIGN)) {
 699                                                 base = 16;      /* if %i */
 700                                                 flags &= ~PFXOK;
 701                                                 goto ok;
 702                                         }
 703                                         break;
 704                                 }
 705
 706                                 /*
 707                                  * If we got here, c is not a legal character
 708                                  * for a number.  Stop accumulating digits.
 709                                  */
 710                                 break;
 711                 ok:
 712                                 /*
 713                                  * c is legal: store it and look at the next.
 714                                  */
 715                                 *p++ = c;
 716                                 if (--fp->_r > 0)
 717                                         fp->_p++;
 718                                 else if (__srefill(fp))
 719                                         break;          /* EOF */
 720                         }
 721                         /*
 722                          * If we had only a sign, it is no good; push
 723                          * back the sign.  If the number ends in `x',
 724                          * it was [sign] '0' 'x', so push back the x
 725                          * and treat it as [sign] '0'.
 726                          */
 727                         if (flags & NDIGITS) {
 728                                 if (p > buf)
 729                                         (void) __ungetc(*(u_char *)--p, fp);
 730                                 goto match_failure;
 731                         }
 732                         c = ((u_char *)p)[-1];
 733                         if (c == 'x' || c == 'X') {
 734                                 --p;
 735                                 (void) __ungetc(c, fp);
 736                         }
 737                         if ((flags & SUPPRESS) == 0) {
 738                                 uintmax_t res;
 739
 740                                 *p = 0;
 741                                 if ((flags & UNSIGNED) == 0)
 742                                     res = strtoimax(buf, (char **)NULL, base);
 743                                 else
 744                                     res = strtoumax(buf, (char **)NULL, base);
 745                                 if (flags & POINTER)
 746                                         *va_arg(ap, void **) =
 747                                                         (void *)(uintptr_t)res;
 748                                 else if (flags & SHORTSHORT)
 749                                         *va_arg(ap, char *) = res;
 750                                 else if (flags & SHORT)
 751                                         *va_arg(ap, short *) = res;
 752                                 else if (flags & LONG)
 753                                         *va_arg(ap, long *) = res;
 754                                 else if (flags & LONGLONG)
 755                                         *va_arg(ap, long long *) = res;
 756                                 else if (flags & INTMAXT)
 757                                         *va_arg(ap, intmax_t *) = res;
 758                                 else if (flags & PTRDIFFT)
 759                                         *va_arg(ap, ptrdiff_t *) = res;
 760                                 else if (flags & SIZET)
 761                                         *va_arg(ap, size_t *) = res;
 762                                 else
 763                                         *va_arg(ap, int *) = res;
 764                                 nassigned++;
 765                         }
 766                         nread += p - buf;
 767                         nconversions++;
 768                         break;
 769
 770 #ifndef NO_FLOATING_POINT
 771                 case CT_FLOAT:
 772                         /* scan a floating point number as if by strtod */
 773                         if (width == 0 || width > sizeof(buf) - 1)
 774                                 width = sizeof(buf) - 1;
 775                         if ((width = parsefloat(fp, buf, buf + width)) == 0)
 776                                 goto match_failure;
 777                         if ((flags & SUPPRESS) == 0) {
 778                                 if (flags & LONGDBL) {
 779                                         long double res = strtold(buf, &p);
 780                                         *va_arg(ap, long double *) = res;
 781                                 } else if (flags & LONG) {
 782                                         double res = strtod(buf, &p);
 783                                         *va_arg(ap, double *) = res;
 784                                 } else {
 785                                         float res = strtof(buf, &p);
 786                                         *va_arg(ap, float *) = res;
 787                                 }
 788                                 if (__scanfdebug && p - buf != width)
 789                                         abort();
 790                                 nassigned++;
 791                         }
 792                         nread += width;
 793                         nconversions++;
 794                         break;
 795 #endif /* !NO_FLOATING_POINT */
 796                 }
 797         }
 798 input_failure:
 799         return (nconversions != 0 ? nassigned : EOF);
 800 match_failure:
 801         return (nassigned);
 802 }
 803
 804 /*
 805  * Fill in the given table from the scanset at the given format
 806  * (just after `[').  Return a pointer to the character past the
 807  * closing `]'.  The table has a 1 wherever characters should be
 808  * considered part of the scanset.
 809  */
 810 static const u_char *
 811 __sccl(tab, fmt)
 812         char *tab;
 813         const u_char *fmt;
 814 {
 815         int c, n, v, i;
 816
 817         /* first `clear' the whole table */
 818         c = *fmt++;             /* first char hat => negated scanset */
 819         if (c == '^') {
 820                 v = 1;          /* default => accept */
 821                 c = *fmt++;     /* get new first char */
 822         } else
 823                 v = 0;          /* default => reject */
 824
 825         /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
 826         (void) memset(tab, v, 256);
 827
 828         if (c == 0)
 829                 return (fmt - 1);/* format ended before closing ] */
 830
 831         /*
 832          * Now set the entries corresponding to the actual scanset
 833          * to the opposite of the above.
 834          *
 835          * The first character may be ']' (or '-') without being special;
 836          * the last character may be '-'.
 837          */
 838         v = 1 - v;
 839         for (;;) {
 840                 tab[c] = v;             /* take character c */
 841 doswitch:
 842                 n = *fmt++;             /* and examine the next */
 843                 switch (n) {
 844
 845                 case 0:                 /* format ended too soon */
 846                         return (fmt - 1);
 847
 848                 case '-':
 849                         /*
 850                          * A scanset of the form
 851                          *      [01+-]
 852                          * is defined as `the digit 0, the digit 1,
 853                          * the character +, the character -', but
 854                          * the effect of a scanset such as
 855                          *      [a-zA-Z0-9]
 856                          * is implementation defined.  The V7 Unix
 857                          * scanf treats `a-z' as `the letters a through
 858                          * z', but treats `a-a' as `the letter a, the
 859                          * character -, and the letter a'.
 860                          *
 861                          * For compatibility, the `-' is not considerd
 862                          * to define a range if the character following
 863                          * it is either a close bracket (required by ANSI)
 864                          * or is not numerically greater than the character
 865                          * we just stored in the table (c).
 866                          */
 867                         n = *fmt;
 868                         if (n == ']'
 869                             || (__collate_load_error ? n < c :
 870                                 __collate_range_cmp (n, c) < 0
 871                                )
 872                            ) {
 873                                 c = '-';
 874                                 break;  /* resume the for(;;) */
 875                         }
 876                         fmt++;
 877                         /* fill in the range */
 878                         if (__collate_load_error) {
 879                                 do {
 880                                         tab[++c] = v;
 881                                 } while (c < n);
 882                         } else {
 883                                 for (i = 0; i < 256; i ++)
 884                                         if (   __collate_range_cmp (c, i) < 0
 885                                             && __collate_range_cmp (i, n) <= 0
 886                                            )
 887                                                 tab[i] = v;
 888                         }
 889 #if 1   /* XXX another disgusting compatibility hack */
 890                         c = n;
 891                         /*
 892                          * Alas, the V7 Unix scanf also treats formats
 893                          * such as [a-c-e] as `the letters a through e'.
 894                          * This too is permitted by the standard....
 895                          */
 896                         goto doswitch;
 897 #else
 898                         c = *fmt++;
 899                         if (c == 0)
 900                                 return (fmt - 1);
 901                         if (c == ']')
 902                                 return (fmt);
 903 #endif
 904                         break;
 905
 906                 case ']':               /* end of scanset */
 907                         return (fmt);
 908
 909                 default:                /* just another character */
 910                         c = n;
 911                         break;
 912                 }
 913         }
 914         /* NOTREACHED */
 915 }
 916
 917 #ifndef NO_FLOATING_POINT
 918 static int
 919 parsefloat(FILE *fp, char *buf, char *end)
 920 {
 921         char *commit, *p;
 922         int infnanpos = 0;
 923         enum {
 924                 S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX,
 925                 S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
 926         } state = S_START;
 927         unsigned char c;
 928         char decpt = *localeconv()->decimal_point;
 929         _Bool gotmantdig = 0, ishex = 0;
 930
 931         /*
 932          * We set commit = p whenever the string we have read so far
 933          * constitutes a valid representation of a floating point
 934          * number by itself.  At some point, the parse will complete
 935          * or fail, and we will ungetc() back to the last commit point.
 936          * To ensure that the file offset gets updated properly, it is
 937          * always necessary to read at least one character that doesn't
 938          * match; thus, we can't short-circuit "infinity" or "nan(...)".
 939          */
 940         commit = buf - 1;
 941         for (p = buf; p < end; ) {
 942                 c = *fp->_p;
 943 reswitch:
 944                 switch (state) {
 945                 case S_START:
 946                         state = S_GOTSIGN;
 947                         if (c == '-' || c == '+')
 948                                 break;
 949                         else
 950                                 goto reswitch;
 951                 case S_GOTSIGN:
 952                         switch (c) {
 953                         case '0':
 954                                 state = S_MAYBEHEX;
 955                                 commit = p;
 956                                 break;
 957                         case 'I':
 958                         case 'i':
 959                                 state = S_INF;
 960                                 break;
 961                         case 'N':
 962                         case 'n':
 963                                 state = S_NAN;
 964                                 break;
 965                         default:
 966                                 state = S_DIGITS;
 967                                 goto reswitch;
 968                         }
 969                         break;
 970                 case S_INF:
 971                         if (infnanpos > 6 ||
 972                             (c != "nfinity"[infnanpos] &&
 973                              c != "NFINITY"[infnanpos]))
 974                                 goto parsedone;
 975                         if (infnanpos == 1 || infnanpos == 6)
 976                                 commit = p;     /* inf or infinity */
 977                         infnanpos++;
 978                         break;
 979                 case S_NAN:
 980                         switch (infnanpos) {
 981                         case -1:        /* XXX kludge to deal with nan(...) */
 982                                 goto parsedone;
 983                         case 0:
 984                                 if (c != 'A' && c != 'a')
 985                                         goto parsedone;
 986                                 break;
 987                         case 1:
 988                                 if (c != 'N' && c != 'n')
 989                                         goto parsedone;
 990                                 else
 991                                         commit = p;
 992                                 break;
 993                         case 2:
 994                                 if (c != '(')
 995                                         goto parsedone;
 996                                 break;
 997                         default:
 998                                 if (c == ')') {
 999                                         commit = p;
1000                                         infnanpos = -2;
1001                                 } else if (!isalnum(c) && c != '_')
1002                                         goto parsedone;
1003                                 break;
1004                         }
1005                         infnanpos++;
1006                         break;
1007                 case S_MAYBEHEX:
1008                         state = S_DIGITS;
1009                         if (c == 'X' || c == 'x') {
1010                                 ishex = 1;
1011                                 break;
1012                         } else {        /* we saw a '0', but no 'x' */
1013                                 gotmantdig = 1;
1014                                 goto reswitch;
1015                         }
1016                 case S_DIGITS:
1017                         if ((ishex && isxdigit(c)) || isdigit(c))
1018                                 gotmantdig = 1;
1019                         else {
1020                                 state = S_FRAC;
1021                                 if (c != decpt)
1022                                         goto reswitch;
1023                         }
1024                         if (gotmantdig)
1025                                 commit = p;
1026                         break;
1027                 case S_FRAC:
1028                         if (((c == 'E' || c == 'e') && !ishex) ||
1029                             ((c == 'P' || c == 'p') && ishex)) {
1030                                 if (!gotmantdig)
1031                                         goto parsedone;
1032                                 else
1033                                         state = S_EXP;
1034                         } else if ((ishex && isxdigit(c)) || isdigit(c)) {
1035                                 commit = p;
1036                                 gotmantdig = 1;
1037                         } else
1038                                 goto parsedone;
1039                         break;
1040                 case S_EXP:
1041                         state = S_EXPDIGITS;
1042                         if (c == '-' || c == '+')
1043                                 break;
1044                         else
1045                                 goto reswitch;
1046                 case S_EXPDIGITS:
1047                         if (isdigit(c))
1048                                 commit = p;
1049                         else
1050                                 goto parsedone;
1051                         break;
1052                 default:
1053                         abort();
1054                 }
1055                 *p++ = c;
1056                 if (--fp->_r > 0)
1057                         fp->_p++;
1058                 else if (__srefill(fp))
1059                         break;  /* EOF */
1060         }
1061
1062 parsedone:
1063         while (commit < --p)
1064                 __ungetc(*(u_char *)p, fp);
1065         *++commit = '\0';
1066         return (commit - buf);
1067 }
1068 #endif