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  * @(#)vfscanf.c        8.1 (Berkeley) 6/4/93
  37  * $FreeBSD: /repoman/r/ncvs/src/lib/libc/stdio/vfscanf.c,v 1.35 2004/01/31 23:16:09 das Exp $
  38  * $DragonFly: src/lib/libc/stdio/vfscanf.c,v 1.9 2005/11/20 11:07:30 swildner Exp $
  39  */
  40
  41 #include "namespace.h"
  42 #include <sys/types.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <ctype.h>
  46 #include <stdarg.h>
  47 #include <string.h>
  48 #include "un-namespace.h"
  49
  50 #include "collate.h"
  51 #include "libc_private.h"
  52 #include "local.h"
  53 #include "priv_stdio.h"
  54
  55 #define FLOATING_POINT
  56
  57 #ifdef FLOATING_POINT
  58 #include <locale.h>
  59 #include "floatio.h"
  60 #endif
  61
  62 #define BUF             513     /* Maximum length of numeric string. */
  63
  64 /*
  65  * Flags used during conversion.
  66  */
  67 #define LONG            0x01    /* l: long or double */
  68 #define LONGDBL         0x02    /* L: long double */
  69 #define SHORT           0x04    /* h: short */
  70 #define SUPPRESS        0x08    /* suppress assignment */
  71 #define POINTER         0x10    /* weird %p pointer (`fake hex') */
  72 #define NOSKIP          0x20    /* do not skip blanks */
  73 #define QUAD            0x400
  74
  75 /*
  76  * The following are used in numeric conversions only:
  77  * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
  78  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
  79  */
  80 #define SIGNOK          0x40    /* +/- is (still) legal */
  81 #define NDIGITS         0x80    /* no digits detected */
  82
  83 #define DPTOK           0x100   /* (float) decimal point is still legal */
  84 #define EXPOK           0x200   /* (float) exponent (e+3, etc) still legal */
  85
  86 #define PFXOK           0x100   /* 0x prefix is (still) legal */
  87 #define NZDIGITS        0x200   /* no zero digits detected */
  88 #define HAVESIGN        0x10000 /* sign detected */
  89
  90 /*
  91  * Conversion types.
  92  */
  93 #define CT_CHAR         0       /* %c conversion */
  94 #define CT_CCL          1       /* %[...] conversion */
  95 #define CT_STRING       2       /* %s conversion */
  96 #define CT_INT          3       /* integer, i.e., strtoq or strtouq */
  97 #define CT_FLOAT        4       /* floating, i.e., strtod */
  98
  99 #define u_char unsigned char
 100 #define u_long unsigned long
 101
 102 static u_char *__sccl(char *, u_char *);
 103
 104 /*
 105  * __vfscanf MT-safe version
 106  */
 107 int
 108 __vfscanf(FILE *fp, char const *fmt0, va_list ap)
 109 {
 110         int ret;
 111
 112         FLOCKFILE(fp);
 113         ret = __svfscanf(fp, fmt0, ap);
 114         FUNLOCKFILE(fp);
 115         return (ret);
 116 }
 117
 118 /*
 119  * __svfscanf - non-MT-safe version of __vfscanf
 120  */
 121 int
 122 __svfscanf(FILE *fp, char const *fmt0, va_list ap)
 123 {
 124         u_char *fmt = (u_char *)fmt0;
 125         int c;                  /* character from format, or conversion */
 126         size_t width;           /* field width, or 0 */
 127         char *p;                /* points into all kinds of strings */
 128         int n;                  /* handy integer */
 129         int flags;              /* flags as defined above */
 130         char *p0;               /* saves original value of p when necessary */
 131         int nassigned;          /* number of fields assigned */
 132         int nconversions;       /* number of conversions */
 133         int nread;              /* number of characters consumed from fp */
 134         int base;               /* base argument to strtoq/strtouq */
 135         u_quad_t(*ccfn)();      /* conversion function (strtoq/strtouq) */
 136         char ccltab[256];       /* character class table for %[...] */
 137         char buf[BUF];          /* buffer for numeric conversions */
 138
 139         /* `basefix' is used to avoid `if' tests in the integer scanner */
 140         static short basefix[17] =
 141                 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
 142 #ifdef FLOATING_POINT
 143         char decimal_point = localeconv()->decimal_point[0];
 144 #endif
 145
 146         nassigned = 0;
 147         nconversions = 0;
 148         nread = 0;
 149         base = 0;               /* XXX just to keep gcc happy */
 150         ccfn = NULL;            /* XXX just to keep gcc happy */
 151         for (;;) {
 152                 c = *fmt++;
 153                 if (c == 0)
 154                         return (nassigned);
 155                 if (isspace(c)) {
 156                         while ((fp->pub._r > 0 || __srefill(fp) == 0) && isspace(*fp->pub._p))
 157                                 nread++, fp->pub._r--, fp->pub._p++;
 158                         continue;
 159                 }
 160                 if (c != '%')
 161                         goto literal;
 162                 width = 0;
 163                 flags = 0;
 164                 /*
 165                  * switch on the format.  continue if done;
 166                  * break once format type is derived.
 167                  */
 168 again:          c = *fmt++;
 169                 switch (c) {
 170                 case '%':
 171 literal:
 172                         if (fp->pub._r <= 0 && __srefill(fp))
 173                                 goto input_failure;
 174                         if (*fp->pub._p != c)
 175                                 goto match_failure;
 176                         fp->pub._r--, fp->pub._p++;
 177                         nread++;
 178                         continue;
 179
 180                 case '*':
 181                         flags |= SUPPRESS;
 182                         goto again;
 183                 case 'l':
 184                         flags |= LONG;
 185                         goto again;
 186                 case 'q':
 187                         flags |= QUAD;
 188                         goto again;
 189                 case 'L':
 190                         flags |= LONGDBL;
 191                         goto again;
 192                 case 'h':
 193                         flags |= SHORT;
 194                         goto again;
 195
 196                 case '0': case '1': case '2': case '3': case '4':
 197                 case '5': case '6': case '7': case '8': case '9':
 198                         width = width * 10 + c - '0';
 199                         goto again;
 200
 201                 /*
 202                  * Conversions.
 203                  * Those marked `compat' are for 4.[123]BSD compatibility.
 204                  *
 205                  * (According to ANSI, E and X formats are supposed
 206                  * to the same as e and x.  Sorry about that.)
 207                  */
 208                 case 'D':       /* compat */
 209                         flags |= LONG;
 210                         /* FALLTHROUGH */
 211                 case 'd':
 212                         c = CT_INT;
 213                         ccfn = (u_quad_t (*)())strtoq;
 214                         base = 10;
 215                         break;
 216
 217                 case 'i':
 218                         c = CT_INT;
 219                         ccfn = (u_quad_t (*)())strtoq;
 220                         base = 0;
 221                         break;
 222
 223                 case 'O':       /* compat */
 224                         flags |= LONG;
 225                         /* FALLTHROUGH */
 226                 case 'o':
 227                         c = CT_INT;
 228                         ccfn = strtouq;
 229                         base = 8;
 230                         break;
 231
 232                 case 'u':
 233                         c = CT_INT;
 234                         ccfn = strtouq;
 235                         base = 10;
 236                         break;
 237
 238                 case 'X':       /* compat   XXX */
 239                         flags |= LONG;
 240                         /* FALLTHROUGH */
 241                 case 'x':
 242                         flags |= PFXOK; /* enable 0x prefixing */
 243                         c = CT_INT;
 244                         ccfn = strtouq;
 245                         base = 16;
 246                         break;
 247
 248 #ifdef FLOATING_POINT
 249                 case 'E':       /* compat   XXX */
 250                 case 'F':       /* compat */
 251                         flags |= LONG;
 252                         /* FALLTHROUGH */
 253                 case 'e': case 'f': case 'g':
 254                         c = CT_FLOAT;
 255                         break;
 256 #endif
 257
 258                 case 's':
 259                         c = CT_STRING;
 260                         break;
 261
 262                 case '[':
 263                         fmt = __sccl(ccltab, fmt);
 264                         flags |= NOSKIP;
 265                         c = CT_CCL;
 266                         break;
 267
 268                 case 'c':
 269                         flags |= NOSKIP;
 270                         c = CT_CHAR;
 271                         break;
 272
 273                 case 'p':       /* pointer format is like hex */
 274                         flags |= POINTER | PFXOK;
 275                         c = CT_INT;
 276                         ccfn = strtouq;
 277                         base = 16;
 278                         break;
 279
 280                 case 'n':
 281                         nconversions++;
 282                         if (flags & SUPPRESS)   /* ??? */
 283                                 continue;
 284                         if (flags & SHORT)
 285                                 *va_arg(ap, short *) = nread;
 286                         else if (flags & LONG)
 287                                 *va_arg(ap, long *) = nread;
 288                         else if (flags & QUAD)
 289                                 *va_arg(ap, quad_t *) = nread;
 290                         else
 291                                 *va_arg(ap, int *) = nread;
 292                         continue;
 293
 294                 /*
 295                  * Disgusting backwards compatibility hacks.    XXX
 296                  */
 297                 case '\0':      /* compat */
 298                         return (EOF);
 299
 300                 default:        /* compat */
 301                         if (isupper(c))
 302                                 flags |= LONG;
 303                         c = CT_INT;
 304                         ccfn = (u_quad_t (*)())strtoq;
 305                         base = 10;
 306                         break;
 307                 }
 308
 309                 /*
 310                  * We have a conversion that requires input.
 311                  */
 312                 if (fp->pub._r <= 0 && __srefill(fp))
 313                         goto input_failure;
 314
 315                 /*
 316                  * Consume leading white space, except for formats
 317                  * that suppress this.
 318                  */
 319                 if ((flags & NOSKIP) == 0) {
 320                         while (isspace(*fp->pub._p)) {
 321                                 nread++;
 322                                 if (--fp->pub._r > 0)
 323                                         fp->pub._p++;
 324                                 else if (__srefill(fp))
 325                                         goto input_failure;
 326                         }
 327                         /*
 328                          * Note that there is at least one character in
 329                          * the buffer, so conversions that do not set NOSKIP
 330                          * ca no longer result in an input failure.
 331                          */
 332                 }
 333
 334                 /*
 335                  * Do the conversion.
 336                  */
 337                 switch (c) {
 338
 339                 case CT_CHAR:
 340                         /* scan arbitrary characters (sets NOSKIP) */
 341                         if (width == 0)
 342                                 width = 1;
 343                         if (flags & SUPPRESS) {
 344                                 size_t sum = 0;
 345                                 for (;;) {
 346                                         if ((n = fp->pub._r) < width) {
 347                                                 sum += n;
 348                                                 width -= n;
 349                                                 fp->pub._p += n;
 350                                                 if (__srefill(fp)) {
 351                                                         if (sum == 0)
 352                                                             goto input_failure;
 353                                                         break;
 354                                                 }
 355                                         } else {
 356                                                 sum += width;
 357                                                 fp->pub._r -= width;
 358                                                 fp->pub._p += width;
 359                                                 break;
 360                                         }
 361                                 }
 362                                 nread += sum;
 363                         } else {
 364                                 size_t r = fread((void *)va_arg(ap, char *), 1,
 365                                     width, fp);
 366
 367                                 if (r == 0)
 368                                         goto input_failure;
 369                                 nread += r;
 370                                 nassigned++;
 371                         }
 372                         nconversions++;
 373                         break;
 374
 375                 case CT_CCL:
 376                         /* scan a (nonempty) character class (sets NOSKIP) */
 377                         if (width == 0)
 378                                 width = (size_t)~0;     /* `infinity' */
 379                         /* take only those things in the class */
 380                         if (flags & SUPPRESS) {
 381                                 n = 0;
 382                                 while (ccltab[*fp->pub._p]) {
 383                                         n++, fp->pub._r--, fp->pub._p++;
 384                                         if (--width == 0)
 385                                                 break;
 386                                         if (fp->pub._r <= 0 && __srefill(fp)) {
 387                                                 if (n == 0)
 388                                                         goto input_failure;
 389                                                 break;
 390                                         }
 391                                 }
 392                                 if (n == 0)
 393                                         goto match_failure;
 394                         } else {
 395                                 p0 = p = va_arg(ap, char *);
 396                                 while (ccltab[*fp->pub._p]) {
 397                                         fp->pub._r--;
 398                                         *p++ = *fp->pub._p++;
 399                                         if (--width == 0)
 400                                                 break;
 401                                         if (fp->pub._r <= 0 && __srefill(fp)) {
 402                                                 if (p == p0)
 403                                                         goto input_failure;
 404                                                 break;
 405                                         }
 406                                 }
 407                                 n = p - p0;
 408                                 if (n == 0)
 409                                         goto match_failure;
 410                                 *p = 0;
 411                                 nassigned++;
 412                         }
 413                         nread += n;
 414                         nconversions++;
 415                         break;
 416
 417                 case CT_STRING:
 418                         /* like CCL, but zero-length string OK, & no NOSKIP */
 419                         if (width == 0)
 420                                 width = (size_t)~0;
 421                         if (flags & SUPPRESS) {
 422                                 n = 0;
 423                                 while (!isspace(*fp->pub._p)) {
 424                                         n++, fp->pub._r--, fp->pub._p++;
 425                                         if (--width == 0)
 426                                                 break;
 427                                         if (fp->pub._r <= 0 && __srefill(fp))
 428                                                 break;
 429                                 }
 430                                 nread += n;
 431                         } else {
 432                                 p0 = p = va_arg(ap, char *);
 433                                 while (!isspace(*fp->pub._p)) {
 434                                         fp->pub._r--;
 435                                         *p++ = *fp->pub._p++;
 436                                         if (--width == 0)
 437                                                 break;
 438                                         if (fp->pub._r <= 0 && __srefill(fp))
 439                                                 break;
 440                                 }
 441                                 *p = 0;
 442                                 nread += p - p0;
 443                                 nassigned++;
 444                         }
 445                         nconversions++;
 446                         continue;
 447
 448                 case CT_INT:
 449                         /* scan an integer as if by strtoq/strtouq */
 450 #ifdef hardway
 451                         if (width == 0 || width > sizeof(buf) - 1)
 452                                 width = sizeof(buf) - 1;
 453 #else
 454                         /* size_t is unsigned, hence this optimisation */
 455                         if (--width > sizeof(buf) - 2)
 456                                 width = sizeof(buf) - 2;
 457                         width++;
 458 #endif
 459                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 460                         for (p = buf; width; width--) {
 461                                 c = *fp->pub._p;
 462                                 /*
 463                                  * Switch on the character; `goto ok'
 464                                  * if we accept it as a part of number.
 465                                  */
 466                                 switch (c) {
 467
 468                                 /*
 469                                  * The digit 0 is always legal, but is
 470                                  * special.  For %i conversions, if no
 471                                  * digits (zero or nonzero) have been
 472                                  * scanned (only signs), we will have
 473                                  * base==0.  In that case, we should set
 474                                  * it to 8 and enable 0x prefixing.
 475                                  * Also, if we have not scanned zero digits
 476                                  * before this, do not turn off prefixing
 477                                  * (someone else will turn it off if we
 478                                  * have scanned any nonzero digits).
 479                                  */
 480                                 case '0':
 481                                         if (base == 0) {
 482                                                 base = 8;
 483                                                 flags |= PFXOK;
 484                                         }
 485                                         if (flags & NZDIGITS)
 486                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 487                                         else
 488                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 489                                         goto ok;
 490
 491                                 /* 1 through 7 always legal */
 492                                 case '1': case '2': case '3':
 493                                 case '4': case '5': case '6': case '7':
 494                                         base = basefix[base];
 495                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 496                                         goto ok;
 497
 498                                 /* digits 8 and 9 ok iff decimal or hex */
 499                                 case '8': case '9':
 500                                         base = basefix[base];
 501                                         if (base <= 8)
 502                                                 break;  /* not legal here */
 503                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 504                                         goto ok;
 505
 506                                 /* letters ok iff hex */
 507                                 case 'A': case 'B': case 'C':
 508                                 case 'D': case 'E': case 'F':
 509                                 case 'a': case 'b': case 'c':
 510                                 case 'd': case 'e': case 'f':
 511                                         /* no need to fix base here */
 512                                         if (base <= 10)
 513                                                 break;  /* not legal here */
 514                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 515                                         goto ok;
 516
 517                                 /* sign ok only as first character */
 518                                 case '+': case '-':
 519                                         if (flags & SIGNOK) {
 520                                                 flags &= ~SIGNOK;
 521                                                 flags |= HAVESIGN;
 522                                                 goto ok;
 523                                         }
 524                                         break;
 525
 526                                 /*
 527                                  * x ok iff flag still set & 2nd char (or
 528                                  * 3rd char if we have a sign).
 529                                  */
 530                                 case 'x': case 'X':
 531                                         if (flags & PFXOK && p ==
 532                                             buf + 1 + !!(flags & HAVESIGN)) {
 533                                                 base = 16;      /* if %i */
 534                                                 flags &= ~PFXOK;
 535                                                 goto ok;
 536                                         }
 537                                         break;
 538                                 }
 539
 540                                 /*
 541                                  * If we got here, c is not a legal character
 542                                  * for a number.  Stop accumulating digits.
 543                                  */
 544                                 break;
 545                 ok:
 546                                 /*
 547                                  * c is legal: store it and look at the next.
 548                                  */
 549                                 *p++ = c;
 550                                 if (--fp->pub._r > 0)
 551                                         fp->pub._p++;
 552                                 else if (__srefill(fp))
 553                                         break;          /* EOF */
 554                         }
 555                         /*
 556                          * If we had only a sign, it is no good; push
 557                          * back the sign.  If the number ends in `x',
 558                          * it was [sign] '0' 'x', so push back the x
 559                          * and treat it as [sign] '0'.
 560                          */
 561                         if (flags & NDIGITS) {
 562                                 if (p > buf)
 563                                         __ungetc(*(u_char *)--p, fp);
 564                                 goto match_failure;
 565                         }
 566                         c = ((u_char *)p)[-1];
 567                         if (c == 'x' || c == 'X') {
 568                                 --p;
 569                                 __ungetc(c, fp);
 570                         }
 571                         if ((flags & SUPPRESS) == 0) {
 572                                 u_quad_t res;
 573
 574                                 *p = 0;
 575                                 res = (*ccfn)(buf, (char **)NULL, base);
 576                                 if (flags & POINTER)
 577                                         *va_arg(ap, void **) =
 578                                                 (void *)(u_long)res;
 579                                 else if (flags & SHORT)
 580                                         *va_arg(ap, short *) = res;
 581                                 else if (flags & LONG)
 582                                         *va_arg(ap, long *) = res;
 583                                 else if (flags & QUAD)
 584                                         *va_arg(ap, quad_t *) = res;
 585                                 else
 586                                         *va_arg(ap, int *) = res;
 587                                 nassigned++;
 588                         }
 589                         nread += p - buf;
 590                         nconversions++;
 591                         break;
 592
 593 #ifdef FLOATING_POINT
 594                 case CT_FLOAT:
 595                         /* scan a floating point number as if by strtod */
 596 #ifdef hardway
 597                         if (width == 0 || width > sizeof(buf) - 1)
 598                                 width = sizeof(buf) - 1;
 599 #else
 600                         /* size_t is unsigned, hence this optimisation */
 601                         if (--width > sizeof(buf) - 2)
 602                                 width = sizeof(buf) - 2;
 603                         width++;
 604 #endif
 605                         flags |= SIGNOK | NDIGITS | DPTOK | EXPOK;
 606                         for (p = buf; width; width--) {
 607                                 c = *fp->pub._p;
 608                                 /*
 609                                  * This code mimicks the integer conversion
 610                                  * code, but is much simpler.
 611                                  */
 612                                 switch (c) {
 613
 614                                 case '0': case '1': case '2': case '3':
 615                                 case '4': case '5': case '6': case '7':
 616                                 case '8': case '9':
 617                                         flags &= ~(SIGNOK | NDIGITS);
 618                                         goto fok;
 619
 620                                 case '+': case '-':
 621                                         if (flags & SIGNOK) {
 622                                                 flags &= ~SIGNOK;
 623                                                 goto fok;
 624                                         }
 625                                         break;
 626                                 case 'e': case 'E':
 627                                         /* no exponent without some digits */
 628                                         if ((flags&(NDIGITS|EXPOK)) == EXPOK) {
 629                                                 flags =
 630                                                     (flags & ~(EXPOK|DPTOK)) |
 631                                                     SIGNOK | NDIGITS;
 632                                                 goto fok;
 633                                         }
 634                                         break;
 635                                 default:
 636                                         if ((char)c == decimal_point &&
 637                                             (flags & DPTOK)) {
 638                                                 flags &= ~(SIGNOK | DPTOK);
 639                                                 goto fok;
 640                                         }
 641                                         break;
 642                                 }
 643                                 break;
 644                 fok:
 645                                 *p++ = c;
 646                                 if (--fp->pub._r > 0)
 647                                         fp->pub._p++;
 648                                 else if (__srefill(fp))
 649                                         break;  /* EOF */
 650                         }
 651                         /*
 652                          * If no digits, might be missing exponent digits
 653                          * (just give back the exponent) or might be missing
 654                          * regular digits, but had sign and/or decimal point.
 655                          */
 656                         if (flags & NDIGITS) {
 657                                 if (flags & EXPOK) {
 658                                         /* no digits at all */
 659                                         while (p > buf)
 660                                                 __ungetc(*(u_char *)--p, fp);
 661                                         goto match_failure;
 662                                 }
 663                                 /* just a bad exponent (e and maybe sign) */
 664                                 c = *(u_char *)--p;
 665                                 if (c != 'e' && c != 'E') {
 666                                         __ungetc(c, fp);/* sign */
 667                                         c = *(u_char *)--p;
 668                                 }
 669                                 __ungetc(c, fp);
 670                         }
 671                         if ((flags & SUPPRESS) == 0) {
 672                                 double res;
 673
 674                                 *p = 0;
 675                                 /* XXX this loses precision for long doubles. */
 676                                 res = strtod(buf, (char **) NULL);
 677                                 if (flags & LONGDBL)
 678                                         *va_arg(ap, long double *) = res;
 679                                 else if (flags & LONG)
 680                                         *va_arg(ap, double *) = res;
 681                                 else
 682                                         *va_arg(ap, float *) = res;
 683                                 nassigned++;
 684                         }
 685                         nread += p - buf;
 686                         nconversions++;
 687                         break;
 688 #endif /* FLOATING_POINT */
 689                 }
 690         }
 691 input_failure:
 692         return (nconversions != 0 ? nassigned : EOF);
 693 match_failure:
 694         return (nassigned);
 695 }
 696
 697 /*
 698  * Fill in the given table from the scanset at the given format
 699  * (just after `[').  Return a pointer to the character past the
 700  * closing `]'.  The table has a 1 wherever characters should be
 701  * considered part of the scanset.
 702  */
 703 static u_char *
 704 __sccl(char *tab, u_char *fmt)
 705 {
 706         int c, n, v, i;
 707
 708         /* first `clear' the whole table */
 709         c = *fmt++;             /* first char hat => negated scanset */
 710         if (c == '^') {
 711                 v = 1;          /* default => accept */
 712                 c = *fmt++;     /* get new first char */
 713         } else
 714                 v = 0;          /* default => reject */
 715
 716         /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
 717         memset(tab, v, 256);
 718
 719         if (c == 0)
 720                 return (fmt - 1);/* format ended before closing ] */
 721
 722         /*
 723          * Now set the entries corresponding to the actual scanset
 724          * to the opposite of the above.
 725          *
 726          * The first character may be ']' (or '-') without being special;
 727          * the last character may be '-'.
 728          */
 729         v = 1 - v;
 730         for (;;) {
 731                 tab[c] = v;             /* take character c */
 732 doswitch:
 733                 n = *fmt++;             /* and examine the next */
 734                 switch (n) {
 735
 736                 case 0:                 /* format ended too soon */
 737                         return (fmt - 1);
 738
 739                 case '-':
 740                         /*
 741                          * A scanset of the form
 742                          *      [01+-]
 743                          * is defined as `the digit 0, the digit 1,
 744                          * the character +, the character -', but
 745                          * the effect of a scanset such as
 746                          *      [a-zA-Z0-9]
 747                          * is implementation defined.  The V7 Unix
 748                          * scanf treats `a-z' as `the letters a through
 749                          * z', but treats `a-a' as `the letter a, the
 750                          * character -, and the letter a'.
 751                          *
 752                          * For compatibility, the `-' is not considerd
 753                          * to define a range if the character following
 754                          * it is either a close bracket (required by ANSI)
 755                          * or is not numerically greater than the character
 756                          * we just stored in the table (c).
 757                          */
 758                         n = *fmt;
 759                         if (n == ']'
 760                             || (__collate_load_error ? n < c :
 761                                 __collate_range_cmp (n, c) < 0
 762                                )
 763                            ) {
 764                                 c = '-';
 765                                 break;  /* resume the for(;;) */
 766                         }
 767                         fmt++;
 768                         /* fill in the range */
 769                         if (__collate_load_error) {
 770                                 do {
 771                                         tab[++c] = v;
 772                                 } while (c < n);
 773                         } else {
 774                                 for (i = 0; i < 256; i ++)
 775                                         if (   __collate_range_cmp (c, i) < 0
 776                                             && __collate_range_cmp (i, n) <= 0
 777                                            )
 778                                                 tab[i] = v;
 779                         }
 780 #if 1   /* XXX another disgusting compatibility hack */
 781                         c = n;
 782                         /*
 783                          * Alas, the V7 Unix scanf also treats formats
 784                          * such as [a-c-e] as `the letters a through e'.
 785                          * This too is permitted by the standard....
 786                          */
 787                         goto doswitch;
 788 #else
 789                         c = *fmt++;
 790                         if (c == 0)
 791                                 return (fmt - 1);
 792                         if (c == ']')
 793                                 return (fmt);
 794 #endif
 795                         break;
 796
 797                 case ']':               /* end of scanset */
 798                         return (fmt);
 799
 800                 default:                /* just another character */
 801                         c = n;
 802                         break;
 803                 }
 804         }
 805         /* NOTREACHED */
 806 }