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#pragma ident "%Z%%M% %I% %E% SMI" 16 17#include <sm/gen.h> 18SM_IDSTR(id, "@(#)$Id: vfscanf.c,v 1.54 2006/10/12 22:03:52 ca Exp $") 19 20#include <ctype.h> 21#include <stdlib.h> 22#include <errno.h> 23#include <setjmp.h> 24#include <sm/time.h> 25#include <sm/varargs.h> 26#include <sm/config.h> 27#include <sm/io.h> 28#include <sm/signal.h> 29#include <sm/clock.h> 30#include <sm/string.h> 31#include "local.h" 32 33#define BUF 513 /* Maximum length of numeric string. */ 34 35/* Flags used during conversion. */ 36#define LONG 0x01 /* l: long or double */ 37#define SHORT 0x04 /* h: short */ 38#define QUAD 0x08 /* q: quad (same as ll) */ 39#define SUPPRESS 0x10 /* suppress assignment */ 40#define POINTER 0x20 /* weird %p pointer (`fake hex') */ 41#define NOSKIP 0x40 /* do not skip blanks */ 42 43/* 44** The following are used in numeric conversions only: 45** SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point; 46** SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral. 47*/ 48 49#define SIGNOK 0x080 /* +/- is (still) legal */ 50#define NDIGITS 0x100 /* no digits detected */ 51 52#define DPTOK 0x200 /* (float) decimal point is still legal */ 53#define EXPOK 0x400 /* (float) exponent (e+3, etc) still legal */ 54 55#define PFXOK 0x200 /* 0x prefix is (still) legal */ 56#define NZDIGITS 0x400 /* no zero digits detected */ 57 58/* Conversion types. */ 59#define CT_CHAR 0 /* %c conversion */ 60#define CT_CCL 1 /* %[...] conversion */ 61#define CT_STRING 2 /* %s conversion */ 62#define CT_INT 3 /* integer, i.e., strtoll or strtoull */ 63#define CT_FLOAT 4 /* floating, i.e., strtod */ 64 65static void scanalrm __P((int)); 66static unsigned char *sm_sccl __P((char *, unsigned char *)); 67static jmp_buf ScanTimeOut; 68 69/* 70** SCANALRM -- handler when timeout activated for sm_io_vfscanf() 71** 72** Returns flow of control to where setjmp(ScanTimeOut) was set. 73** 74** Parameters: 75** sig -- unused 76** 77** Returns: 78** does not return 79** 80** Side Effects: 81** returns flow of control to setjmp(ScanTimeOut). 82** 83** NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER. DO NOT ADD 84** ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE 85** DOING. 86*/ 87 88/* ARGSUSED0 */ 89static void 90scanalrm(sig) 91 int sig; 92{ 93 longjmp(ScanTimeOut, 1); 94} 95 96/* 97** SM_VFSCANF -- convert input into data units 98** 99** Parameters: 100** fp -- file pointer for input data 101** timeout -- time intvl allowed to complete (milliseconds) 102** fmt0 -- format for finding data units 103** ap -- vectors for memory location for storing data units 104** 105** Results: 106** Success: number of data units assigned 107** Failure: SM_IO_EOF 108*/ 109 110int 111sm_vfscanf(fp, timeout, fmt0, ap) 112 register SM_FILE_T *fp; 113 int SM_NONVOLATILE timeout; 114 char const *fmt0; 115 va_list SM_NONVOLATILE ap; 116{ 117 register unsigned char *SM_NONVOLATILE fmt = (unsigned char *) fmt0; 118 register int c; /* character from format, or conversion */ 119 register size_t width; /* field width, or 0 */ 120 register char *p; /* points into all kinds of strings */ 121 register int n; /* handy integer */ 122 register int flags; /* flags as defined above */ 123 register char *p0; /* saves original value of p when necessary */ 124 int nassigned; /* number of fields assigned */ 125 int nread; /* number of characters consumed from fp */ 126 int base; /* base argument to strtoll/strtoull */ 127 128 /* conversion function (strtoll/strtoull) */ 129 ULONGLONG_T (*ccfn) __P((const char *, char **, int)); 130 char ccltab[256]; /* character class table for %[...] */ 131 char buf[BUF]; /* buffer for numeric conversions */ 132 SM_EVENT *evt = NULL; 133 134 /* `basefix' is used to avoid `if' tests in the integer scanner */ 135 static short basefix[17] = 136 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 137 138 if (timeout == SM_TIME_DEFAULT) 139 timeout = fp->f_timeout; 140 if (timeout == SM_TIME_IMMEDIATE) 141 { 142 /* 143 ** Filling the buffer will take time and we are wanted to 144 ** return immediately. So... 145 */ 146 147 errno = EAGAIN; 148 return SM_IO_EOF; 149 } 150 151 if (timeout != SM_TIME_FOREVER) 152 { 153 if (setjmp(ScanTimeOut) != 0) 154 { 155 errno = EAGAIN; 156 return SM_IO_EOF; 157 } 158 159 evt = sm_seteventm(timeout, scanalrm, 0); 160 } 161 162 nassigned = 0; 163 nread = 0; 164 base = 0; /* XXX just to keep gcc happy */ 165 ccfn = NULL; /* XXX just to keep gcc happy */ 166 for (;;) 167 { 168 c = *fmt++; 169 if (c == 0) 170 { 171 if (evt != NULL) 172 sm_clrevent(evt); /* undo our timeout */ 173 return nassigned; 174 } 175 if (isspace(c)) 176 { 177 while ((fp->f_r > 0 || sm_refill(fp, SM_TIME_FOREVER) 178 == 0) && 179 isspace(*fp->f_p)) 180 nread++, fp->f_r--, fp->f_p++; 181 continue; 182 } 183 if (c != '%') 184 goto literal; 185 width = 0; 186 flags = 0; 187 188 /* 189 ** switch on the format. continue if done; 190 ** break once format type is derived. 191 */ 192 193again: c = *fmt++; 194 switch (c) 195 { 196 case '%': 197literal: 198 if (fp->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER)) 199 goto input_failure; 200 if (*fp->f_p != c) 201 goto match_failure; 202 fp->f_r--, fp->f_p++; 203 nread++; 204 continue; 205 206 case '*': 207 flags |= SUPPRESS; 208 goto again; 209 case 'h': 210 flags |= SHORT; 211 goto again; 212 case 'l': 213 if (*fmt == 'l') 214 { 215 fmt++; 216 flags |= QUAD; 217 } 218 else 219 { 220 flags |= LONG; 221 } 222 goto again; 223 case 'q': 224 flags |= QUAD; 225 goto again; 226 227 case '0': case '1': case '2': case '3': case '4': 228 case '5': case '6': case '7': case '8': case '9': 229 width = width * 10 + c - '0'; 230 goto again; 231 232 /* 233 ** Conversions. 234 ** Those marked `compat' are for 4.[123]BSD compatibility. 235 ** 236 ** (According to ANSI, E and X formats are supposed 237 ** to the same as e and x. Sorry about that.) 238 */ 239 240 case 'D': /* compat */ 241 flags |= LONG; 242 /* FALLTHROUGH */ 243 case 'd': 244 c = CT_INT; 245 ccfn = (ULONGLONG_T (*)())sm_strtoll; 246 base = 10; 247 break; 248 249 case 'i': 250 c = CT_INT; 251 ccfn = (ULONGLONG_T (*)())sm_strtoll; 252 base = 0; 253 break; 254 255 case 'O': /* compat */ 256 flags |= LONG; 257 /* FALLTHROUGH */ 258 case 'o': 259 c = CT_INT; 260 ccfn = sm_strtoull; 261 base = 8; 262 break; 263 264 case 'u': 265 c = CT_INT; 266 ccfn = sm_strtoull; 267 base = 10; 268 break; 269 270 case 'X': 271 case 'x': 272 flags |= PFXOK; /* enable 0x prefixing */ 273 c = CT_INT; 274 ccfn = sm_strtoull; 275 base = 16; 276 break; 277 278 case 'E': 279 case 'G': 280 case 'e': 281 case 'f': 282 case 'g': 283 c = CT_FLOAT; 284 break; 285 286 case 's': 287 c = CT_STRING; 288 break; 289 290 case '[': 291 fmt = sm_sccl(ccltab, fmt); 292 flags |= NOSKIP; 293 c = CT_CCL; 294 break; 295 296 case 'c': 297 flags |= NOSKIP; 298 c = CT_CHAR; 299 break; 300 301 case 'p': /* pointer format is like hex */ 302 flags |= POINTER | PFXOK; 303 c = CT_INT; 304 ccfn = sm_strtoull; 305 base = 16; 306 break; 307 308 case 'n': 309 if (flags & SUPPRESS) /* ??? */ 310 continue; 311 if (flags & SHORT) 312 *SM_VA_ARG(ap, short *) = nread; 313 else if (flags & LONG) 314 *SM_VA_ARG(ap, long *) = nread; 315 else 316 *SM_VA_ARG(ap, int *) = nread; 317 continue; 318 319 /* Disgusting backwards compatibility hacks. XXX */ 320 case '\0': /* compat */ 321 if (evt != NULL) 322 sm_clrevent(evt); /* undo our timeout */ 323 return SM_IO_EOF; 324 325 default: /* compat */ 326 if (isupper(c)) 327 flags |= LONG; 328 c = CT_INT; 329 ccfn = (ULONGLONG_T (*)()) sm_strtoll; 330 base = 10; 331 break; 332 } 333 334 /* We have a conversion that requires input. */ 335 if (fp->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER)) 336 goto input_failure; 337 338 /* 339 ** Consume leading white space, except for formats 340 ** that suppress this. 341 */ 342 343 if ((flags & NOSKIP) == 0) 344 { 345 while (isspace(*fp->f_p)) 346 { 347 nread++; 348 if (--fp->f_r > 0) 349 fp->f_p++; 350 else if (sm_refill(fp, SM_TIME_FOREVER)) 351 goto input_failure; 352 } 353 /* 354 ** Note that there is at least one character in 355 ** the buffer, so conversions that do not set NOSKIP 356 ** can no longer result in an input failure. 357 */ 358 } 359 360 /* Do the conversion. */ 361 switch (c) 362 { 363 case CT_CHAR: 364 /* scan arbitrary characters (sets NOSKIP) */ 365 if (width == 0) 366 width = 1; 367 if (flags & SUPPRESS) 368 { 369 size_t sum = 0; 370 for (;;) 371 { 372 if ((size_t) (n = fp->f_r) < width) 373 { 374 sum += n; 375 width -= n; 376 fp->f_p += n; 377 if (sm_refill(fp, 378 SM_TIME_FOREVER)) 379 { 380 if (sum == 0) 381 goto input_failure; 382 break; 383 } 384 } 385 else 386 { 387 sum += width; 388 fp->f_r -= width; 389 fp->f_p += width; 390 break; 391 } 392 } 393 nread += sum; 394 } 395 else 396 { 397 size_t r; 398 399 r = sm_io_read(fp, SM_TIME_FOREVER, 400 (void *) SM_VA_ARG(ap, char *), 401 width); 402 if (r == 0) 403 goto input_failure; 404 nread += r; 405 nassigned++; 406 } 407 break; 408 409 case CT_CCL: 410 /* scan a (nonempty) character class (sets NOSKIP) */ 411 if (width == 0) 412 width = (size_t)~0; /* `infinity' */ 413 414 /* take only those things in the class */ 415 if (flags & SUPPRESS) 416 { 417 n = 0; 418 while (ccltab[*fp->f_p] != '\0') 419 { 420 n++, fp->f_r--, fp->f_p++; 421 if (--width == 0) 422 break; 423 if (fp->f_r <= 0 && 424 sm_refill(fp, SM_TIME_FOREVER)) 425 { 426 if (n == 0) /* XXX how? */ 427 goto input_failure; 428 break; 429 } 430 } 431 if (n == 0) 432 goto match_failure; 433 } 434 else 435 { 436 p0 = p = SM_VA_ARG(ap, char *); 437 while (ccltab[*fp->f_p] != '\0') 438 { 439 fp->f_r--; 440 *p++ = *fp->f_p++; 441 if (--width == 0) 442 break; 443 if (fp->f_r <= 0 && 444 sm_refill(fp, SM_TIME_FOREVER)) 445 { 446 if (p == p0) 447 goto input_failure; 448 break; 449 } 450 } 451 n = p - p0; 452 if (n == 0) 453 goto match_failure; 454 *p = 0; 455 nassigned++; 456 } 457 nread += n; 458 break; 459 460 case CT_STRING: 461 /* like CCL, but zero-length string OK, & no NOSKIP */ 462 if (width == 0) 463 width = (size_t)~0; 464 if (flags & SUPPRESS) 465 { 466 n = 0; 467 while (!isspace(*fp->f_p)) 468 { 469 n++, fp->f_r--, fp->f_p++; 470 if (--width == 0) 471 break; 472 if (fp->f_r <= 0 && 473 sm_refill(fp, SM_TIME_FOREVER)) 474 break; 475 } 476 nread += n; 477 } 478 else 479 { 480 p0 = p = SM_VA_ARG(ap, char *); 481 while (!isspace(*fp->f_p)) 482 { 483 fp->f_r--; 484 *p++ = *fp->f_p++; 485 if (--width == 0) 486 break; 487 if (fp->f_r <= 0 && 488 sm_refill(fp, SM_TIME_FOREVER)) 489 break; 490 } 491 *p = 0; 492 nread += p - p0; 493 nassigned++; 494 } 495 continue; 496 497 case CT_INT: 498 /* scan an integer as if by strtoll/strtoull */ 499#if SM_CONF_BROKEN_SIZE_T 500 if (width == 0 || width > sizeof(buf) - 1) 501 width = sizeof(buf) - 1; 502#else /* SM_CONF_BROKEN_SIZE_T */ 503 /* size_t is unsigned, hence this optimisation */ 504 if (--width > sizeof(buf) - 2) 505 width = sizeof(buf) - 2; 506 width++; 507#endif /* SM_CONF_BROKEN_SIZE_T */ 508 flags |= SIGNOK | NDIGITS | NZDIGITS; 509 for (p = buf; width > 0; width--) 510 { 511 c = *fp->f_p; 512 513 /* 514 ** Switch on the character; `goto ok' 515 ** if we accept it as a part of number. 516 */ 517 518 switch (c) 519 { 520 521 /* 522 ** The digit 0 is always legal, but is 523 ** special. For %i conversions, if no 524 ** digits (zero or nonzero) have been 525 ** scanned (only signs), we will have 526 ** base==0. In that case, we should set 527 ** it to 8 and enable 0x prefixing. 528 ** Also, if we have not scanned zero digits 529 ** before this, do not turn off prefixing 530 ** (someone else will turn it off if we 531 ** have scanned any nonzero digits). 532 */ 533 534 case '0': 535 if (base == 0) 536 { 537 base = 8; 538 flags |= PFXOK; 539 } 540 if (flags & NZDIGITS) 541 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 542 else 543 flags &= ~(SIGNOK|PFXOK|NDIGITS); 544 goto ok; 545 546 /* 1 through 7 always legal */ 547 case '1': case '2': case '3': 548 case '4': case '5': case '6': case '7': 549 base = basefix[base]; 550 flags &= ~(SIGNOK | PFXOK | NDIGITS); 551 goto ok; 552 553 /* digits 8 and 9 ok iff decimal or hex */ 554 case '8': case '9': 555 base = basefix[base]; 556 if (base <= 8) 557 break; /* not legal here */ 558 flags &= ~(SIGNOK | PFXOK | NDIGITS); 559 goto ok; 560 561 /* letters ok iff hex */ 562 case 'A': case 'B': case 'C': 563 case 'D': case 'E': case 'F': 564 case 'a': case 'b': case 'c': 565 case 'd': case 'e': case 'f': 566 567 /* no need to fix base here */ 568 if (base <= 10) 569 break; /* not legal here */ 570 flags &= ~(SIGNOK | PFXOK | NDIGITS); 571 goto ok; 572 573 /* sign ok only as first character */ 574 case '+': case '-': 575 if (flags & SIGNOK) 576 { 577 flags &= ~SIGNOK; 578 goto ok; 579 } 580 break; 581 582 /* x ok iff flag still set & 2nd char */ 583 case 'x': case 'X': 584 if (flags & PFXOK && p == buf + 1) 585 { 586 base = 16; /* if %i */ 587 flags &= ~PFXOK; 588 goto ok; 589 } 590 break; 591 } 592 593 /* 594 ** If we got here, c is not a legal character 595 ** for a number. Stop accumulating digits. 596 */ 597 598 break; 599 ok: 600 /* c is legal: store it and look at the next. */ 601 *p++ = c; 602 if (--fp->f_r > 0) 603 fp->f_p++; 604 else if (sm_refill(fp, SM_TIME_FOREVER)) 605 break; /* SM_IO_EOF */ 606 } 607 608 /* 609 ** If we had only a sign, it is no good; push 610 ** back the sign. If the number ends in `x', 611 ** it was [sign] '0' 'x', so push back the x 612 ** and treat it as [sign] '0'. 613 */ 614 615 if (flags & NDIGITS) 616 { 617 if (p > buf) 618 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, 619 *(unsigned char *)--p); 620 goto match_failure; 621 } 622 c = ((unsigned char *)p)[-1]; 623 if (c == 'x' || c == 'X') 624 { 625 --p; 626 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c); 627 } 628 if ((flags & SUPPRESS) == 0) 629 { 630 ULONGLONG_T res; 631 632 *p = 0; 633 res = (*ccfn)(buf, (char **)NULL, base); 634 if (flags & POINTER) 635 *SM_VA_ARG(ap, void **) = 636 (void *)(long) res; 637 else if (flags & QUAD) 638 *SM_VA_ARG(ap, LONGLONG_T *) = res; 639 else if (flags & LONG) 640 *SM_VA_ARG(ap, long *) = res; 641 else if (flags & SHORT) 642 *SM_VA_ARG(ap, short *) = res; 643 else 644 *SM_VA_ARG(ap, int *) = res; 645 nassigned++; 646 } 647 nread += p - buf; 648 break; 649 650 case CT_FLOAT: 651 /* scan a floating point number as if by strtod */ 652 if (width == 0 || width > sizeof(buf) - 1) 653 width = sizeof(buf) - 1; 654 flags |= SIGNOK | NDIGITS | DPTOK | EXPOK; 655 for (p = buf; width; width--) 656 { 657 c = *fp->f_p; 658 659 /* 660 ** This code mimicks the integer conversion 661 ** code, but is much simpler. 662 */ 663 664 switch (c) 665 { 666 667 case '0': case '1': case '2': case '3': 668 case '4': case '5': case '6': case '7': 669 case '8': case '9': 670 flags &= ~(SIGNOK | NDIGITS); 671 goto fok; 672 673 case '+': case '-': 674 if (flags & SIGNOK) 675 { 676 flags &= ~SIGNOK; 677 goto fok; 678 } 679 break; 680 case '.': 681 if (flags & DPTOK) 682 { 683 flags &= ~(SIGNOK | DPTOK); 684 goto fok; 685 } 686 break; 687 case 'e': case 'E': 688 689 /* no exponent without some digits */ 690 if ((flags&(NDIGITS|EXPOK)) == EXPOK) 691 { 692 flags = 693 (flags & ~(EXPOK|DPTOK)) | 694 SIGNOK | NDIGITS; 695 goto fok; 696 } 697 break; 698 } 699 break; 700 fok: 701 *p++ = c; 702 if (--fp->f_r > 0) 703 fp->f_p++; 704 else if (sm_refill(fp, SM_TIME_FOREVER)) 705 break; /* SM_IO_EOF */ 706 } 707 708 /* 709 ** If no digits, might be missing exponent digits 710 ** (just give back the exponent) or might be missing 711 ** regular digits, but had sign and/or decimal point. 712 */ 713 714 if (flags & NDIGITS) 715 { 716 if (flags & EXPOK) 717 { 718 /* no digits at all */ 719 while (p > buf) 720 (void) sm_io_ungetc(fp, 721 SM_TIME_DEFAULT, 722 *(unsigned char *)--p); 723 goto match_failure; 724 } 725 726 /* just a bad exponent (e and maybe sign) */ 727 c = *(unsigned char *) --p; 728 if (c != 'e' && c != 'E') 729 { 730 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, 731 c); /* sign */ 732 c = *(unsigned char *)--p; 733 } 734 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c); 735 } 736 if ((flags & SUPPRESS) == 0) 737 { 738 double res; 739 740 *p = 0; 741 res = strtod(buf, (char **) NULL); 742 if (flags & LONG) 743 *SM_VA_ARG(ap, double *) = res; 744 else 745 *SM_VA_ARG(ap, float *) = res; 746 nassigned++; 747 } 748 nread += p - buf; 749 break; 750 } 751 } 752input_failure: 753 if (evt != NULL) 754 sm_clrevent(evt); /* undo our timeout */ 755 return nassigned ? nassigned : -1; 756match_failure: 757 if (evt != NULL) 758 sm_clrevent(evt); /* undo our timeout */ 759 return nassigned; 760} 761 762/* 763** SM_SCCL -- sequenced character comparison list 764** 765** Fill in the given table from the scanset at the given format 766** (just after `['). Return a pointer to the character past the 767** closing `]'. The table has a 1 wherever characters should be 768** considered part of the scanset. 769** 770** Parameters: 771** tab -- array flagging "active" char's to match (returned) 772** fmt -- character list (within "[]") 773** 774** Results: 775*/ 776 777static unsigned char * 778sm_sccl(tab, fmt) 779 register char *tab; 780 register unsigned char *fmt; 781{ 782 register int c, n, v; 783 784 /* first `clear' the whole table */ 785 c = *fmt++; /* first char hat => negated scanset */ 786 if (c == '^') 787 { 788 v = 1; /* default => accept */ 789 c = *fmt++; /* get new first char */ 790 } 791 else 792 v = 0; /* default => reject */ 793 794 /* should probably use memset here */ 795 for (n = 0; n < 256; n++) 796 tab[n] = v; 797 if (c == 0) 798 return fmt - 1; /* format ended before closing ] */ 799 800 /* 801 ** Now set the entries corresponding to the actual scanset 802 ** to the opposite of the above. 803 ** 804 ** The first character may be ']' (or '-') without being special; 805 ** the last character may be '-'. 806 */ 807 808 v = 1 - v; 809 for (;;) 810 { 811 tab[c] = v; /* take character c */ 812doswitch: 813 n = *fmt++; /* and examine the next */ 814 switch (n) 815 { 816 817 case 0: /* format ended too soon */ 818 return fmt - 1; 819 820 case '-': 821 /* 822 ** A scanset of the form 823 ** [01+-] 824 ** is defined as `the digit 0, the digit 1, 825 ** the character +, the character -', but 826 ** the effect of a scanset such as 827 ** [a-zA-Z0-9] 828 ** is implementation defined. The V7 Unix 829 ** scanf treats `a-z' as `the letters a through 830 ** z', but treats `a-a' as `the letter a, the 831 ** character -, and the letter a'. 832 ** 833 ** For compatibility, the `-' is not considerd 834 ** to define a range if the character following 835 ** it is either a close bracket (required by ANSI) 836 ** or is not numerically greater than the character 837 ** we just stored in the table (c). 838 */ 839 840 n = *fmt; 841 if (n == ']' || n < c) 842 { 843 c = '-'; 844 break; /* resume the for(;;) */ 845 } 846 fmt++; 847 do 848 { 849 /* fill in the range */ 850 tab[++c] = v; 851 } while (c < n); 852#if 1 /* XXX another disgusting compatibility hack */ 853 854 /* 855 ** Alas, the V7 Unix scanf also treats formats 856 ** such as [a-c-e] as `the letters a through e'. 857 ** This too is permitted by the standard.... 858 */ 859 860 goto doswitch; 861#else 862 c = *fmt++; 863 if (c == 0) 864 return fmt - 1; 865 if (c == ']') 866 return fmt; 867 break; 868#endif 869 870 case ']': /* end of scanset */ 871 return fmt; 872 873 default: /* just another character */ 874 c = n; 875 break; 876 } 877 } 878 /* NOTREACHED */ 879} 880