contrib/sendmail-8.14/libsm/vfscanf.c

   1 /*
   2  * Copyright (c) 2000-2001, 2004 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  * Copyright (c) 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Chris Torek.
   9  *
  10  * By using this file, you agree to the terms and conditions set
  11  * forth in the LICENSE file which can be found at the top level of
  12  * the sendmail distribution.
  13  */
  14
  15 #include <sm/gen.h>
  16 SM_IDSTR(id, "@(#)$Id: vfscanf.c,v 1.54 2006/10/12 22:03:52 ca Exp $")
  17
  18 #include <ctype.h>
  19 #include <stdlib.h>
  20 #include <errno.h>
  21 #include <setjmp.h>
  22 #include <sm/time.h>
  23 #include <sm/varargs.h>
  24 #include <sm/config.h>
  25 #include <sm/io.h>
  26 #include <sm/signal.h>
  27 #include <sm/clock.h>
  28 #include <sm/string.h>
  29 #include "local.h"
  30
  31 #define BUF             513     /* Maximum length of numeric string. */
  32
  33 /* Flags used during conversion. */
  34 #define LONG            0x01    /* l: long or double */
  35 #define SHORT           0x04    /* h: short */
  36 #define QUAD            0x08    /* q: quad (same as ll) */
  37 #define SUPPRESS        0x10    /* suppress assignment */
  38 #define POINTER         0x20    /* weird %p pointer (`fake hex') */
  39 #define NOSKIP          0x40    /* do not skip blanks */
  40
  41 /*
  42 **  The following are used in numeric conversions only:
  43 **  SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
  44 **  SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
  45 */
  46
  47 #define SIGNOK          0x080   /* +/- is (still) legal */
  48 #define NDIGITS         0x100   /* no digits detected */
  49
  50 #define DPTOK           0x200   /* (float) decimal point is still legal */
  51 #define EXPOK           0x400   /* (float) exponent (e+3, etc) still legal */
  52
  53 #define PFXOK           0x200   /* 0x prefix is (still) legal */
  54 #define NZDIGITS        0x400   /* no zero digits detected */
  55
  56 /* Conversion types. */
  57 #define CT_CHAR         0       /* %c conversion */
  58 #define CT_CCL          1       /* %[...] conversion */
  59 #define CT_STRING       2       /* %s conversion */
  60 #define CT_INT          3       /* integer, i.e., strtoll or strtoull */
  61 #define CT_FLOAT        4       /* floating, i.e., strtod */
  62
  63 static void             scanalrm __P((int));
  64 static unsigned char    *sm_sccl __P((char *, unsigned char *));
  65 static jmp_buf          ScanTimeOut;
  66
  67 /*
  68 **  SCANALRM -- handler when timeout activated for sm_io_vfscanf()
  69 **
  70 **  Returns flow of control to where setjmp(ScanTimeOut) was set.
  71 **
  72 **      Parameters:
  73 **              sig -- unused
  74 **
  75 **      Returns:
  76 **              does not return
  77 **
  78 **      Side Effects:
  79 **              returns flow of control to setjmp(ScanTimeOut).
  80 **
  81 **      NOTE:   THIS CAN BE CALLED FROM A SIGNAL HANDLER.  DO NOT ADD
  82 **              ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
  83 **              DOING.
  84 */
  85
  86 /* ARGSUSED0 */
  87 static void
  88 scanalrm(sig)
  89         int sig;
  90 {
  91         longjmp(ScanTimeOut, 1);
  92 }
  93
  94 /*
  95 **  SM_VFSCANF -- convert input into data units
  96 **
  97 **      Parameters:
  98 **              fp -- file pointer for input data
  99 **              timeout -- time intvl allowed to complete (milliseconds)
 100 **              fmt0 -- format for finding data units
 101 **              ap -- vectors for memory location for storing data units
 102 **
 103 **      Results:
 104 **              Success: number of data units assigned
 105 **              Failure: SM_IO_EOF
 106 */
 107
 108 int
 109 sm_vfscanf(fp, timeout, fmt0, ap)
 110         register SM_FILE_T *fp;
 111         int SM_NONVOLATILE timeout;
 112         char const *fmt0;
 113         va_list SM_NONVOLATILE ap;
 114 {
 115         register unsigned char *SM_NONVOLATILE fmt = (unsigned char *) fmt0;
 116         register int c;         /* character from format, or conversion */
 117         register size_t width;  /* field width, or 0 */
 118         register char *p;       /* points into all kinds of strings */
 119         register int n;         /* handy integer */
 120         register int flags;     /* flags as defined above */
 121         register char *p0;      /* saves original value of p when necessary */
 122         int nassigned;          /* number of fields assigned */
 123         int nread;              /* number of characters consumed from fp */
 124         int base;               /* base argument to strtoll/strtoull */
 125
 126         /* conversion function (strtoll/strtoull) */
 127         ULONGLONG_T (*ccfn) __P((const char *, char **, int));
 128         char ccltab[256];       /* character class table for %[...] */
 129         char buf[BUF];          /* buffer for numeric conversions */
 130         SM_EVENT *evt = NULL;
 131
 132         /* `basefix' is used to avoid `if' tests in the integer scanner */
 133         static short basefix[17] =
 134                 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
 135
 136         if (timeout == SM_TIME_DEFAULT)
 137                 timeout = fp->f_timeout;
 138         if (timeout == SM_TIME_IMMEDIATE)
 139         {
 140                 /*
 141                 **  Filling the buffer will take time and we are wanted to
 142                 **  return immediately. So...
 143                 */
 144
 145                 errno = EAGAIN;
 146                 return SM_IO_EOF;
 147         }
 148
 149         if (timeout != SM_TIME_FOREVER)
 150         {
 151                 if (setjmp(ScanTimeOut) != 0)
 152                 {
 153                         errno = EAGAIN;
 154                         return SM_IO_EOF;
 155                 }
 156
 157                 evt = sm_seteventm(timeout, scanalrm, 0);
 158         }
 159
 160         nassigned = 0;
 161         nread = 0;
 162         base = 0;               /* XXX just to keep gcc happy */
 163         ccfn = NULL;            /* XXX just to keep gcc happy */
 164         for (;;)
 165         {
 166                 c = *fmt++;
 167                 if (c == 0)
 168                 {
 169                         if (evt != NULL)
 170                                 sm_clrevent(evt); /*  undo our timeout */
 171                         return nassigned;
 172                 }
 173                 if (isspace(c))
 174                 {
 175                         while ((fp->f_r > 0 || sm_refill(fp, SM_TIME_FOREVER)
 176                                                 == 0) &&
 177                             isspace(*fp->f_p))
 178                                 nread++, fp->f_r--, fp->f_p++;
 179                         continue;
 180                 }
 181                 if (c != '%')
 182                         goto literal;
 183                 width = 0;
 184                 flags = 0;
 185
 186                 /*
 187                 **  switch on the format.  continue if done;
 188                 **  break once format type is derived.
 189                 */
 190
 191 again:          c = *fmt++;
 192                 switch (c)
 193                 {
 194                   case '%':
 195 literal:
 196                         if (fp->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER))
 197                                 goto input_failure;
 198                         if (*fp->f_p != c)
 199                                 goto match_failure;
 200                         fp->f_r--, fp->f_p++;
 201                         nread++;
 202                         continue;
 203
 204                   case '*':
 205                         flags |= SUPPRESS;
 206                         goto again;
 207                   case 'h':
 208                         flags |= SHORT;
 209                         goto again;
 210                   case 'l':
 211                         if (*fmt == 'l')
 212                         {
 213                                 fmt++;
 214                                 flags |= QUAD;
 215                         }
 216                         else
 217                         {
 218                                 flags |= LONG;
 219                         }
 220                         goto again;
 221                   case 'q':
 222                         flags |= QUAD;
 223                         goto again;
 224
 225                   case '0': case '1': case '2': case '3': case '4':
 226                   case '5': case '6': case '7': case '8': case '9':
 227                         width = width * 10 + c - '0';
 228                         goto again;
 229
 230                 /*
 231                 **  Conversions.
 232                 **  Those marked `compat' are for 4.[123]BSD compatibility.
 233                 **
 234                 **  (According to ANSI, E and X formats are supposed
 235                 **  to the same as e and x.  Sorry about that.)
 236                 */
 237
 238                   case 'D':     /* compat */
 239                         flags |= LONG;
 240                         /* FALLTHROUGH */
 241                   case 'd':
 242                         c = CT_INT;
 243                         ccfn = (ULONGLONG_T (*)())sm_strtoll;
 244                         base = 10;
 245                         break;
 246
 247                   case 'i':
 248                         c = CT_INT;
 249                         ccfn = (ULONGLONG_T (*)())sm_strtoll;
 250                         base = 0;
 251                         break;
 252
 253                   case 'O':     /* compat */
 254                         flags |= LONG;
 255                         /* FALLTHROUGH */
 256                   case 'o':
 257                         c = CT_INT;
 258                         ccfn = sm_strtoull;
 259                         base = 8;
 260                         break;
 261
 262                   case 'u':
 263                         c = CT_INT;
 264                         ccfn = sm_strtoull;
 265                         base = 10;
 266                         break;
 267
 268                   case 'X':
 269                   case 'x':
 270                         flags |= PFXOK; /* enable 0x prefixing */
 271                         c = CT_INT;
 272                         ccfn = sm_strtoull;
 273                         base = 16;
 274                         break;
 275
 276                   case 'E':
 277                   case 'G':
 278                   case 'e':
 279                   case 'f':
 280                   case 'g':
 281                         c = CT_FLOAT;
 282                         break;
 283
 284                   case 's':
 285                         c = CT_STRING;
 286                         break;
 287
 288                   case '[':
 289                         fmt = sm_sccl(ccltab, fmt);
 290                         flags |= NOSKIP;
 291                         c = CT_CCL;
 292                         break;
 293
 294                   case 'c':
 295                         flags |= NOSKIP;
 296                         c = CT_CHAR;
 297                         break;
 298
 299                   case 'p':     /* pointer format is like hex */
 300                         flags |= POINTER | PFXOK;
 301                         c = CT_INT;
 302                         ccfn = sm_strtoull;
 303                         base = 16;
 304                         break;
 305
 306                   case 'n':
 307                         if (flags & SUPPRESS)   /* ??? */
 308                                 continue;
 309                         if (flags & SHORT)
 310                                 *SM_VA_ARG(ap, short *) = nread;
 311                         else if (flags & LONG)
 312                                 *SM_VA_ARG(ap, long *) = nread;
 313                         else
 314                                 *SM_VA_ARG(ap, int *) = nread;
 315                         continue;
 316
 317                 /* Disgusting backwards compatibility hacks.    XXX */
 318                   case '\0':    /* compat */
 319                         if (evt != NULL)
 320                                 sm_clrevent(evt); /*  undo our timeout */
 321                         return SM_IO_EOF;
 322
 323                   default:      /* compat */
 324                         if (isupper(c))
 325                                 flags |= LONG;
 326                         c = CT_INT;
 327                         ccfn = (ULONGLONG_T (*)()) sm_strtoll;
 328                         base = 10;
 329                         break;
 330                 }
 331
 332                 /* We have a conversion that requires input. */
 333                 if (fp->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER))
 334                         goto input_failure;
 335
 336                 /*
 337                 **  Consume leading white space, except for formats
 338                 **  that suppress this.
 339                 */
 340
 341                 if ((flags & NOSKIP) == 0)
 342                 {
 343                         while (isspace(*fp->f_p))
 344                         {
 345                                 nread++;
 346                                 if (--fp->f_r > 0)
 347                                         fp->f_p++;
 348                                 else if (sm_refill(fp, SM_TIME_FOREVER))
 349                                         goto input_failure;
 350                         }
 351                         /*
 352                         **  Note that there is at least one character in
 353                         **  the buffer, so conversions that do not set NOSKIP
 354                         **  can no longer result in an input failure.
 355                         */
 356                 }
 357
 358                 /* Do the conversion. */
 359                 switch (c)
 360                 {
 361                   case CT_CHAR:
 362                         /* scan arbitrary characters (sets NOSKIP) */
 363                         if (width == 0)
 364                                 width = 1;
 365                         if (flags & SUPPRESS)
 366                         {
 367                                 size_t sum = 0;
 368                                 for (;;)
 369                                 {
 370                                         if ((size_t) (n = fp->f_r) < width)
 371                                         {
 372                                                 sum += n;
 373                                                 width -= n;
 374                                                 fp->f_p += n;
 375                                                 if (sm_refill(fp,
 376                                                               SM_TIME_FOREVER))
 377                                                 {
 378                                                         if (sum == 0)
 379                                                                 goto input_failure;
 380                                                         break;
 381                                                 }
 382                                         }
 383                                         else
 384                                         {
 385                                                 sum += width;
 386                                                 fp->f_r -= width;
 387                                                 fp->f_p += width;
 388                                                 break;
 389                                         }
 390                                 }
 391                                 nread += sum;
 392                         }
 393                         else
 394                         {
 395                                 size_t r;
 396
 397                                 r = sm_io_read(fp, SM_TIME_FOREVER,
 398                                                 (void *) SM_VA_ARG(ap, char *),
 399                                                 width);
 400                                 if (r == 0)
 401                                         goto input_failure;
 402                                 nread += r;
 403                                 nassigned++;
 404                         }
 405                         break;
 406
 407                   case CT_CCL:
 408                         /* scan a (nonempty) character class (sets NOSKIP) */
 409                         if (width == 0)
 410                                 width = (size_t)~0;     /* `infinity' */
 411
 412                         /* take only those things in the class */
 413                         if (flags & SUPPRESS)
 414                         {
 415                                 n = 0;
 416                                 while (ccltab[*fp->f_p] != '\0')
 417                                 {
 418                                         n++, fp->f_r--, fp->f_p++;
 419                                         if (--width == 0)
 420                                                 break;
 421                                         if (fp->f_r <= 0 &&
 422                                             sm_refill(fp, SM_TIME_FOREVER))
 423                                         {
 424                                                 if (n == 0) /* XXX how? */
 425                                                         goto input_failure;
 426                                                 break;
 427                                         }
 428                                 }
 429                                 if (n == 0)
 430                                         goto match_failure;
 431                         }
 432                         else
 433                         {
 434                                 p0 = p = SM_VA_ARG(ap, char *);
 435                                 while (ccltab[*fp->f_p] != '\0')
 436                                 {
 437                                         fp->f_r--;
 438                                         *p++ = *fp->f_p++;
 439                                         if (--width == 0)
 440                                                 break;
 441                                         if (fp->f_r <= 0 &&
 442                                             sm_refill(fp, SM_TIME_FOREVER))
 443                                         {
 444                                                 if (p == p0)
 445                                                         goto input_failure;
 446                                                 break;
 447                                         }
 448                                 }
 449                                 n = p - p0;
 450                                 if (n == 0)
 451                                         goto match_failure;
 452                                 *p = 0;
 453                                 nassigned++;
 454                         }
 455                         nread += n;
 456                         break;
 457
 458                   case CT_STRING:
 459                         /* like CCL, but zero-length string OK, & no NOSKIP */
 460                         if (width == 0)
 461                                 width = (size_t)~0;
 462                         if (flags & SUPPRESS)
 463                         {
 464                                 n = 0;
 465                                 while (!isspace(*fp->f_p))
 466                                 {
 467                                         n++, fp->f_r--, fp->f_p++;
 468                                         if (--width == 0)
 469                                                 break;
 470                                         if (fp->f_r <= 0 &&
 471                                             sm_refill(fp, SM_TIME_FOREVER))
 472                                                 break;
 473                                 }
 474                                 nread += n;
 475                         }
 476                         else
 477                         {
 478                                 p0 = p = SM_VA_ARG(ap, char *);
 479                                 while (!isspace(*fp->f_p))
 480                                 {
 481                                         fp->f_r--;
 482                                         *p++ = *fp->f_p++;
 483                                         if (--width == 0)
 484                                                 break;
 485                                         if (fp->f_r <= 0 &&
 486                                             sm_refill(fp, SM_TIME_FOREVER))
 487                                                 break;
 488                                 }
 489                                 *p = 0;
 490                                 nread += p - p0;
 491                                 nassigned++;
 492                         }
 493                         continue;
 494
 495                   case CT_INT:
 496                         /* scan an integer as if by strtoll/strtoull */
 497 #if SM_CONF_BROKEN_SIZE_T
 498                         if (width == 0 || width > sizeof(buf) - 1)
 499                                 width = sizeof(buf) - 1;
 500 #else /* SM_CONF_BROKEN_SIZE_T */
 501                         /* size_t is unsigned, hence this optimisation */
 502                         if (--width > sizeof(buf) - 2)
 503                                 width = sizeof(buf) - 2;
 504                         width++;
 505 #endif /* SM_CONF_BROKEN_SIZE_T */
 506                         flags |= SIGNOK | NDIGITS | NZDIGITS;
 507                         for (p = buf; width > 0; width--)
 508                         {
 509                                 c = *fp->f_p;
 510
 511                                 /*
 512                                 **  Switch on the character; `goto ok'
 513                                 **  if we accept it as a part of number.
 514                                 */
 515
 516                                 switch (c)
 517                                 {
 518
 519                                 /*
 520                                 **  The digit 0 is always legal, but is
 521                                 **  special.  For %i conversions, if no
 522                                 **  digits (zero or nonzero) have been
 523                                 **  scanned (only signs), we will have
 524                                 **  base==0.  In that case, we should set
 525                                 **  it to 8 and enable 0x prefixing.
 526                                 **  Also, if we have not scanned zero digits
 527                                 **  before this, do not turn off prefixing
 528                                 **  (someone else will turn it off if we
 529                                 **  have scanned any nonzero digits).
 530                                 */
 531
 532                                   case '0':
 533                                         if (base == 0)
 534                                         {
 535                                                 base = 8;
 536                                                 flags |= PFXOK;
 537                                         }
 538                                         if (flags & NZDIGITS)
 539                                             flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
 540                                         else
 541                                             flags &= ~(SIGNOK|PFXOK|NDIGITS);
 542                                         goto ok;
 543
 544                                 /* 1 through 7 always legal */
 545                                   case '1': case '2': case '3':
 546                                   case '4': case '5': case '6': case '7':
 547                                         base = basefix[base];
 548                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 549                                         goto ok;
 550
 551                                 /* digits 8 and 9 ok iff decimal or hex */
 552                                   case '8': case '9':
 553                                         base = basefix[base];
 554                                         if (base <= 8)
 555                                                 break;  /* not legal here */
 556                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 557                                         goto ok;
 558
 559                                 /* letters ok iff hex */
 560                                   case 'A': case 'B': case 'C':
 561                                   case 'D': case 'E': case 'F':
 562                                   case 'a': case 'b': case 'c':
 563                                   case 'd': case 'e': case 'f':
 564
 565                                         /* no need to fix base here */
 566                                         if (base <= 10)
 567                                                 break;  /* not legal here */
 568                                         flags &= ~(SIGNOK | PFXOK | NDIGITS);
 569                                         goto ok;
 570
 571                                 /* sign ok only as first character */
 572                                   case '+': case '-':
 573                                         if (flags & SIGNOK)
 574                                         {
 575                                                 flags &= ~SIGNOK;
 576                                                 goto ok;
 577                                         }
 578                                         break;
 579
 580                                 /* x ok iff flag still set & 2nd char */
 581                                   case 'x': case 'X':
 582                                         if (flags & PFXOK && p == buf + 1)
 583                                         {
 584                                                 base = 16;      /* if %i */
 585                                                 flags &= ~PFXOK;
 586                                                 goto ok;
 587                                         }
 588                                         break;
 589                                 }
 590
 591                                 /*
 592                                 **  If we got here, c is not a legal character
 593                                 **  for a number.  Stop accumulating digits.
 594                                 */
 595
 596                                 break;
 597                 ok:
 598                                 /* c is legal: store it and look at the next. */
 599                                 *p++ = c;
 600                                 if (--fp->f_r > 0)
 601                                         fp->f_p++;
 602                                 else if (sm_refill(fp, SM_TIME_FOREVER))
 603                                         break;          /* SM_IO_EOF */
 604                         }
 605
 606                         /*
 607                         **  If we had only a sign, it is no good; push
 608                         **  back the sign.  If the number ends in `x',
 609                         **  it was [sign] '0' 'x', so push back the x
 610                         **  and treat it as [sign] '0'.
 611                         */
 612
 613                         if (flags & NDIGITS)
 614                         {
 615                                 if (p > buf)
 616                                         (void) sm_io_ungetc(fp, SM_TIME_DEFAULT,
 617                                                             *(unsigned char *)--p);
 618                                 goto match_failure;
 619                         }
 620                         c = ((unsigned char *)p)[-1];
 621                         if (c == 'x' || c == 'X')
 622                         {
 623                                 --p;
 624                                 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
 625                         }
 626                         if ((flags & SUPPRESS) == 0)
 627                         {
 628                                 ULONGLONG_T res;
 629
 630                                 *p = 0;
 631                                 res = (*ccfn)(buf, (char **)NULL, base);
 632                                 if (flags & POINTER)
 633                                         *SM_VA_ARG(ap, void **) =
 634                                             (void *)(long) res;
 635                                 else if (flags & QUAD)
 636                                         *SM_VA_ARG(ap, LONGLONG_T *) = res;
 637                                 else if (flags & LONG)
 638                                         *SM_VA_ARG(ap, long *) = res;
 639                                 else if (flags & SHORT)
 640                                         *SM_VA_ARG(ap, short *) = res;
 641                                 else
 642                                         *SM_VA_ARG(ap, int *) = res;
 643                                 nassigned++;
 644                         }
 645                         nread += p - buf;
 646                         break;
 647
 648                   case CT_FLOAT:
 649                         /* scan a floating point number as if by strtod */
 650                         if (width == 0 || width > sizeof(buf) - 1)
 651                                 width = sizeof(buf) - 1;
 652                         flags |= SIGNOK | NDIGITS | DPTOK | EXPOK;
 653                         for (p = buf; width; width--)
 654                         {
 655                                 c = *fp->f_p;
 656
 657                                 /*
 658                                 **  This code mimicks the integer conversion
 659                                 **  code, but is much simpler.
 660                                 */
 661
 662                                 switch (c)
 663                                 {
 664
 665                                   case '0': case '1': case '2': case '3':
 666                                   case '4': case '5': case '6': case '7':
 667                                   case '8': case '9':
 668                                         flags &= ~(SIGNOK | NDIGITS);
 669                                         goto fok;
 670
 671                                   case '+': case '-':
 672                                         if (flags & SIGNOK)
 673                                         {
 674                                                 flags &= ~SIGNOK;
 675                                                 goto fok;
 676                                         }
 677                                         break;
 678                                   case '.':
 679                                         if (flags & DPTOK)
 680                                         {
 681                                                 flags &= ~(SIGNOK | DPTOK);
 682                                                 goto fok;
 683                                         }
 684                                         break;
 685                                   case 'e': case 'E':
 686
 687                                         /* no exponent without some digits */
 688                                         if ((flags&(NDIGITS|EXPOK)) == EXPOK)
 689                                         {
 690                                                 flags =
 691                                                     (flags & ~(EXPOK|DPTOK)) |
 692                                                     SIGNOK | NDIGITS;
 693                                                 goto fok;
 694                                         }
 695                                         break;
 696                                 }
 697                                 break;
 698                 fok:
 699                                 *p++ = c;
 700                                 if (--fp->f_r > 0)
 701                                         fp->f_p++;
 702                                 else if (sm_refill(fp, SM_TIME_FOREVER))
 703                                         break;  /* SM_IO_EOF */
 704                         }
 705
 706                         /*
 707                         **  If no digits, might be missing exponent digits
 708                         **  (just give back the exponent) or might be missing
 709                         **  regular digits, but had sign and/or decimal point.
 710                         */
 711
 712                         if (flags & NDIGITS)
 713                         {
 714                                 if (flags & EXPOK)
 715                                 {
 716                                         /* no digits at all */
 717                                         while (p > buf)
 718                                                 (void) sm_io_ungetc(fp,
 719                                                              SM_TIME_DEFAULT,
 720                                                              *(unsigned char *)--p);
 721                                         goto match_failure;
 722                                 }
 723
 724                                 /* just a bad exponent (e and maybe sign) */
 725                                 c = *(unsigned char *) --p;
 726                                 if (c != 'e' && c != 'E')
 727                                 {
 728                                         (void) sm_io_ungetc(fp, SM_TIME_DEFAULT,
 729                                                             c); /* sign */
 730                                         c = *(unsigned char *)--p;
 731                                 }
 732                                 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
 733                         }
 734                         if ((flags & SUPPRESS) == 0)
 735                         {
 736                                 double res;
 737
 738                                 *p = 0;
 739                                 res = strtod(buf, (char **) NULL);
 740                                 if (flags & LONG)
 741                                         *SM_VA_ARG(ap, double *) = res;
 742                                 else
 743                                         *SM_VA_ARG(ap, float *) = res;
 744                                 nassigned++;
 745                         }
 746                         nread += p - buf;
 747                         break;
 748                 }
 749         }
 750 input_failure:
 751         if (evt != NULL)
 752                 sm_clrevent(evt); /*  undo our timeout */
 753         return nassigned ? nassigned : -1;
 754 match_failure:
 755         if (evt != NULL)
 756                 sm_clrevent(evt); /*  undo our timeout */
 757         return nassigned;
 758 }
 759
 760 /*
 761 **  SM_SCCL -- sequenced character comparison list
 762 **
 763 **  Fill in the given table from the scanset at the given format
 764 **  (just after `[').  Return a pointer to the character past the
 765 **  closing `]'.  The table has a 1 wherever characters should be
 766 **  considered part of the scanset.
 767 **
 768 **      Parameters:
 769 **              tab -- array flagging "active" char's to match (returned)
 770 **              fmt -- character list (within "[]")
 771 **
 772 **      Results:
 773 */
 774
 775 static unsigned char *
 776 sm_sccl(tab, fmt)
 777         register char *tab;
 778         register unsigned char *fmt;
 779 {
 780         register int c, n, v;
 781
 782         /* first `clear' the whole table */
 783         c = *fmt++;             /* first char hat => negated scanset */
 784         if (c == '^')
 785         {
 786                 v = 1;          /* default => accept */
 787                 c = *fmt++;     /* get new first char */
 788         }
 789         else
 790                 v = 0;          /* default => reject */
 791
 792         /* should probably use memset here */
 793         for (n = 0; n < 256; n++)
 794                 tab[n] = v;
 795         if (c == 0)
 796                 return fmt - 1; /* format ended before closing ] */
 797
 798         /*
 799         **  Now set the entries corresponding to the actual scanset
 800         **  to the opposite of the above.
 801         **
 802         **  The first character may be ']' (or '-') without being special;
 803         **  the last character may be '-'.
 804         */
 805
 806         v = 1 - v;
 807         for (;;)
 808         {
 809                 tab[c] = v;             /* take character c */
 810 doswitch:
 811                 n = *fmt++;             /* and examine the next */
 812                 switch (n)
 813                 {
 814
 815                   case 0:                       /* format ended too soon */
 816                         return fmt - 1;
 817
 818                   case '-':
 819                         /*
 820                         **  A scanset of the form
 821                         **      [01+-]
 822                         **  is defined as `the digit 0, the digit 1,
 823                         **  the character +, the character -', but
 824                         **  the effect of a scanset such as
 825                         **      [a-zA-Z0-9]
 826                         **  is implementation defined.  The V7 Unix
 827                         **  scanf treats `a-z' as `the letters a through
 828                         **  z', but treats `a-a' as `the letter a, the
 829                         **  character -, and the letter a'.
 830                         **
 831                         **  For compatibility, the `-' is not considerd
 832                         **  to define a range if the character following
 833                         **  it is either a close bracket (required by ANSI)
 834                         **  or is not numerically greater than the character
 835                         **  we just stored in the table (c).
 836                         */
 837
 838                         n = *fmt;
 839                         if (n == ']' || n < c)
 840                         {
 841                                 c = '-';
 842                                 break;  /* resume the for(;;) */
 843                         }
 844                         fmt++;
 845                         do
 846                         {
 847                                 /* fill in the range */
 848                                 tab[++c] = v;
 849                         } while (c < n);
 850 #if 1   /* XXX another disgusting compatibility hack */
 851
 852                         /*
 853                         **  Alas, the V7 Unix scanf also treats formats
 854                         **  such as [a-c-e] as `the letters a through e'.
 855                         **  This too is permitted by the standard....
 856                         */
 857
 858                         goto doswitch;
 859 #else
 860                         c = *fmt++;
 861                         if (c == 0)
 862                                 return fmt - 1;
 863                         if (c == ']')
 864                                 return fmt;
 865                         break;
 866 #endif
 867
 868                   case ']':             /* end of scanset */
 869                         return fmt;
 870
 871                   default:              /* just another character */
 872                         c = n;
 873                         break;
 874                 }
 875         }
 876         /* NOTREACHED */
 877 }