1 /* $OpenBSD: vfscanf.c,v 1.31 2014/03/19 05:17:01 guenther Exp $ */ 2 /*- 3 * Copyright (c) 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Chris Torek. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <ctype.h> 35 #include <wctype.h> 36 #include <inttypes.h> 37 #include <stdarg.h> 38 #include <stddef.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include "local.h" 43 44 #ifdef FLOATING_POINT 45 #include "floatio.h" 46 #endif 47 48 #define BUF 513 /* Maximum length of numeric string. */ 49 50 /* 51 * Flags used during conversion. 52 */ 53 #define LONG 0x00001 /* l: long or double */ 54 #define LONGDBL 0x00002 /* L: long double */ 55 #define SHORT 0x00004 /* h: short */ 56 #define SHORTSHORT 0x00008 /* hh: 8 bit integer */ 57 #define LLONG 0x00010 /* ll: long long (+ deprecated q: quad) */ 58 #define POINTER 0x00020 /* p: void * (as hex) */ 59 #define SIZEINT 0x00040 /* z: (signed) size_t */ 60 #define MAXINT 0x00080 /* j: intmax_t */ 61 #define PTRINT 0x00100 /* t: ptrdiff_t */ 62 #define NOSKIP 0x00200 /* [ or c: do not skip blanks */ 63 #define SUPPRESS 0x00400 /* *: suppress assignment */ 64 #define UNSIGNED 0x00800 /* %[oupxX] conversions */ 65 66 /* 67 * The following are used in numeric conversions only: 68 * SIGNOK, HAVESIGN, NDIGITS, DPTOK, and EXPOK are for floating point; 69 * SIGNOK, HAVESIGN, NDIGITS, PFXOK, and NZDIGITS are for integral. 70 */ 71 #define SIGNOK 0x01000 /* +/- is (still) legal */ 72 #define HAVESIGN 0x02000 /* sign detected */ 73 #define NDIGITS 0x04000 /* no digits detected */ 74 75 #define DPTOK 0x08000 /* (float) decimal point is still legal */ 76 #define EXPOK 0x10000 /* (float) exponent (e+3, etc) still legal */ 77 78 #define PFXOK 0x08000 /* 0x prefix is (still) legal */ 79 #define NZDIGITS 0x10000 /* no zero digits detected */ 80 81 /* 82 * Conversion types. 83 */ 84 #define CT_CHAR 0 /* %c conversion */ 85 #define CT_CCL 1 /* %[...] conversion */ 86 #define CT_STRING 2 /* %s conversion */ 87 #define CT_INT 3 /* integer, i.e., strtoimax or strtoumax */ 88 #define CT_FLOAT 4 /* floating, i.e., strtod */ 89 90 #define u_char unsigned char 91 #define u_long unsigned long 92 93 static u_char *__sccl(char *, u_char *); 94 95 /* 96 * Internal, unlocked version of vfscanf 97 */ 98 int 99 __svfscanf(FILE *fp, const char *fmt0, __va_list ap) 100 { 101 u_char *fmt = (u_char *)fmt0; 102 int c; /* character from format, or conversion */ 103 size_t width; /* field width, or 0 */ 104 char *p; /* points into all kinds of strings */ 105 int n; /* handy integer */ 106 int flags; /* flags as defined above */ 107 char *p0; /* saves original value of p when necessary */ 108 int nassigned; /* number of fields assigned */ 109 int nread; /* number of characters consumed from fp */ 110 int base; /* base argument to strtoimax/strtouimax */ 111 char ccltab[256]; /* character class table for %[...] */ 112 char buf[BUF]; /* buffer for numeric conversions */ 113 #ifdef SCANF_WIDE_CHAR 114 wchar_t *wcp; /* handy wide character pointer */ 115 size_t nconv; /* length of multibyte sequence converted */ 116 mbstate_t mbs; 117 #endif 118 119 /* `basefix' is used to avoid `if' tests in the integer scanner */ 120 static short basefix[17] = 121 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 122 123 _SET_ORIENTATION(fp, -1); 124 125 nassigned = 0; 126 nread = 0; 127 base = 0; /* XXX just to keep gcc happy */ 128 for (;;) { 129 c = *fmt++; 130 if (c == 0) 131 return (nassigned); 132 if (isspace(c)) { 133 while ((fp->_r > 0 || __srefill(fp) == 0) && 134 isspace(*fp->_p)) 135 nread++, fp->_r--, fp->_p++; 136 continue; 137 } 138 if (c != '%') 139 goto literal; 140 width = 0; 141 flags = 0; 142 /* 143 * switch on the format. continue if done; 144 * break once format type is derived. 145 */ 146 again: c = *fmt++; 147 switch (c) { 148 case '%': 149 literal: 150 if (fp->_r <= 0 && __srefill(fp)) 151 goto input_failure; 152 if (*fp->_p != c) 153 goto match_failure; 154 fp->_r--, fp->_p++; 155 nread++; 156 continue; 157 158 case '*': 159 flags |= SUPPRESS; 160 goto again; 161 case 'j': 162 flags |= MAXINT; 163 goto again; 164 case 'L': 165 flags |= LONGDBL; 166 goto again; 167 case 'h': 168 if (*fmt == 'h') { 169 fmt++; 170 flags |= SHORTSHORT; 171 } else { 172 flags |= SHORT; 173 } 174 goto again; 175 case 'l': 176 if (*fmt == 'l') { 177 fmt++; 178 flags |= LLONG; 179 } else { 180 flags |= LONG; 181 } 182 goto again; 183 case 'q': 184 flags |= LLONG; /* deprecated */ 185 goto again; 186 case 't': 187 flags |= PTRINT; 188 goto again; 189 case 'z': 190 flags |= SIZEINT; 191 goto again; 192 193 case '0': case '1': case '2': case '3': case '4': 194 case '5': case '6': case '7': case '8': case '9': 195 width = width * 10 + c - '0'; 196 goto again; 197 198 /* 199 * Conversions. 200 * Those marked `compat' are for 4.[123]BSD compatibility. 201 * 202 * (According to ANSI, E and X formats are supposed 203 * to the same as e and x. Sorry about that.) 204 */ 205 case 'D': /* compat */ 206 flags |= LONG; 207 /* FALLTHROUGH */ 208 case 'd': 209 c = CT_INT; 210 base = 10; 211 break; 212 213 case 'i': 214 c = CT_INT; 215 base = 0; 216 break; 217 218 case 'O': /* compat */ 219 flags |= LONG; 220 /* FALLTHROUGH */ 221 case 'o': 222 c = CT_INT; 223 flags |= UNSIGNED; 224 base = 8; 225 break; 226 227 case 'u': 228 c = CT_INT; 229 flags |= UNSIGNED; 230 base = 10; 231 break; 232 233 case 'X': 234 case 'x': 235 flags |= PFXOK; /* enable 0x prefixing */ 236 c = CT_INT; 237 flags |= UNSIGNED; 238 base = 16; 239 break; 240 241 #ifdef FLOATING_POINT 242 case 'e': case 'E': 243 case 'f': case 'F': 244 case 'g': case 'G': 245 case 'a': case 'A': 246 c = CT_FLOAT; 247 break; 248 #endif 249 250 case 's': 251 c = CT_STRING; 252 break; 253 254 case '[': 255 fmt = __sccl(ccltab, fmt); 256 flags |= NOSKIP; 257 c = CT_CCL; 258 break; 259 260 case 'c': 261 flags |= NOSKIP; 262 c = CT_CHAR; 263 break; 264 265 case 'p': /* pointer format is like hex */ 266 flags |= POINTER | PFXOK; 267 c = CT_INT; 268 flags |= UNSIGNED; 269 base = 16; 270 break; 271 272 case 'n': 273 if (flags & SUPPRESS) 274 continue; 275 if (flags & SHORTSHORT) 276 *va_arg(ap, signed char *) = nread; 277 else if (flags & SHORT) 278 *va_arg(ap, short *) = nread; 279 else if (flags & LONG) 280 *va_arg(ap, long *) = nread; 281 else if (flags & SIZEINT) 282 *va_arg(ap, ssize_t *) = nread; 283 else if (flags & PTRINT) 284 *va_arg(ap, ptrdiff_t *) = nread; 285 else if (flags & LLONG) 286 *va_arg(ap, long long *) = nread; 287 else if (flags & MAXINT) 288 *va_arg(ap, intmax_t *) = nread; 289 else 290 *va_arg(ap, int *) = nread; 291 continue; 292 293 /* 294 * Disgusting backwards compatibility hacks. XXX 295 */ 296 case '\0': /* compat */ 297 return (EOF); 298 299 default: /* compat */ 300 if (isupper(c)) 301 flags |= LONG; 302 c = CT_INT; 303 base = 10; 304 break; 305 } 306 307 /* 308 * We have a conversion that requires input. 309 */ 310 if (fp->_r <= 0 && __srefill(fp)) 311 goto input_failure; 312 313 /* 314 * Consume leading white space, except for formats 315 * that suppress this. 316 */ 317 if ((flags & NOSKIP) == 0) { 318 while (isspace(*fp->_p)) { 319 nread++; 320 if (--fp->_r > 0) 321 fp->_p++; 322 else if (__srefill(fp)) 323 goto input_failure; 324 } 325 /* 326 * Note that there is at least one character in 327 * the buffer, so conversions that do not set NOSKIP 328 * ca no longer result in an input failure. 329 */ 330 } 331 332 /* 333 * Do the conversion. 334 */ 335 switch (c) { 336 337 case CT_CHAR: 338 /* scan arbitrary characters (sets NOSKIP) */ 339 if (width == 0) 340 width = 1; 341 #ifdef SCANF_WIDE_CHAR 342 if (flags & LONG) { 343 if ((flags & SUPPRESS) == 0) 344 wcp = va_arg(ap, wchar_t *); 345 else 346 wcp = NULL; 347 n = 0; 348 while (width != 0) { 349 if (n == MB_CUR_MAX) { 350 fp->_flags |= __SERR; 351 goto input_failure; 352 } 353 buf[n++] = *fp->_p; 354 fp->_p++; 355 fp->_r--; 356 bzero(&mbs, sizeof(mbs)); 357 nconv = mbrtowc(wcp, buf, n, &mbs); 358 if (nconv == (size_t)-1) { 359 fp->_flags |= __SERR; 360 goto input_failure; 361 } 362 if (nconv == 0 && !(flags & SUPPRESS)) 363 *wcp = L'\0'; 364 if (nconv != (size_t)-2) { 365 nread += n; 366 width--; 367 if (!(flags & SUPPRESS)) 368 wcp++; 369 n = 0; 370 } 371 if (fp->_r <= 0 && __srefill(fp)) { 372 if (n != 0) { 373 fp->_flags |= __SERR; 374 goto input_failure; 375 } 376 break; 377 } 378 } 379 if (!(flags & SUPPRESS)) 380 nassigned++; 381 } else 382 #endif /* SCANF_WIDE_CHAR */ 383 if (flags & SUPPRESS) { 384 size_t sum = 0; 385 for (;;) { 386 if ((n = fp->_r) < width) { 387 sum += n; 388 width -= n; 389 fp->_p += n; 390 if (__srefill(fp)) { 391 if (sum == 0) 392 goto input_failure; 393 break; 394 } 395 } else { 396 sum += width; 397 fp->_r -= width; 398 fp->_p += width; 399 break; 400 } 401 } 402 nread += sum; 403 } else { 404 size_t r = fread((void *)va_arg(ap, char *), 1, 405 width, fp); 406 407 if (r == 0) 408 goto input_failure; 409 nread += r; 410 nassigned++; 411 } 412 break; 413 414 case CT_CCL: 415 /* scan a (nonempty) character class (sets NOSKIP) */ 416 if (width == 0) 417 width = (size_t)~0; /* `infinity' */ 418 #ifdef SCANF_WIDE_CHAR 419 /* take only those things in the class */ 420 if (flags & LONG) { 421 wchar_t twc; 422 int nchars; 423 424 if ((flags & SUPPRESS) == 0) 425 wcp = va_arg(ap, wchar_t *); 426 else 427 wcp = &twc; 428 n = 0; 429 nchars = 0; 430 while (width != 0) { 431 if (n == MB_CUR_MAX) { 432 fp->_flags |= __SERR; 433 goto input_failure; 434 } 435 buf[n++] = *fp->_p; 436 fp->_p++; 437 fp->_r--; 438 bzero(&mbs, sizeof(mbs)); 439 nconv = mbrtowc(wcp, buf, n, &mbs); 440 if (nconv == (size_t)-1) { 441 fp->_flags |= __SERR; 442 goto input_failure; 443 } 444 if (nconv == 0) 445 *wcp = L'\0'; 446 if (nconv != (size_t)-2) { 447 if (wctob(*wcp) != EOF && 448 !ccltab[wctob(*wcp)]) { 449 while (n != 0) { 450 n--; 451 ungetc(buf[n], 452 fp); 453 } 454 break; 455 } 456 nread += n; 457 width--; 458 if (!(flags & SUPPRESS)) 459 wcp++; 460 nchars++; 461 n = 0; 462 } 463 if (fp->_r <= 0 && __srefill(fp)) { 464 if (n != 0) { 465 fp->_flags |= __SERR; 466 goto input_failure; 467 } 468 break; 469 } 470 } 471 if (n != 0) { 472 fp->_flags |= __SERR; 473 goto input_failure; 474 } 475 n = nchars; 476 if (n == 0) 477 goto match_failure; 478 if (!(flags & SUPPRESS)) { 479 *wcp = L'\0'; 480 nassigned++; 481 } 482 } else 483 #endif /* SCANF_WIDE_CHAR */ 484 /* take only those things in the class */ 485 if (flags & SUPPRESS) { 486 n = 0; 487 while (ccltab[*fp->_p]) { 488 n++, fp->_r--, fp->_p++; 489 if (--width == 0) 490 break; 491 if (fp->_r <= 0 && __srefill(fp)) { 492 if (n == 0) 493 goto input_failure; 494 break; 495 } 496 } 497 if (n == 0) 498 goto match_failure; 499 } else { 500 p0 = p = va_arg(ap, char *); 501 while (ccltab[*fp->_p]) { 502 fp->_r--; 503 *p++ = *fp->_p++; 504 if (--width == 0) 505 break; 506 if (fp->_r <= 0 && __srefill(fp)) { 507 if (p == p0) 508 goto input_failure; 509 break; 510 } 511 } 512 n = p - p0; 513 if (n == 0) 514 goto match_failure; 515 *p = '\0'; 516 nassigned++; 517 } 518 nread += n; 519 break; 520 521 case CT_STRING: 522 /* like CCL, but zero-length string OK, & no NOSKIP */ 523 if (width == 0) 524 width = (size_t)~0; 525 #ifdef SCANF_WIDE_CHAR 526 if (flags & LONG) { 527 wchar_t twc; 528 529 if ((flags & SUPPRESS) == 0) 530 wcp = va_arg(ap, wchar_t *); 531 else 532 wcp = &twc; 533 n = 0; 534 while (!isspace(*fp->_p) && width != 0) { 535 if (n == MB_CUR_MAX) { 536 fp->_flags |= __SERR; 537 goto input_failure; 538 } 539 buf[n++] = *fp->_p; 540 fp->_p++; 541 fp->_r--; 542 bzero(&mbs, sizeof(mbs)); 543 nconv = mbrtowc(wcp, buf, n, &mbs); 544 if (nconv == (size_t)-1) { 545 fp->_flags |= __SERR; 546 goto input_failure; 547 } 548 if (nconv == 0) 549 *wcp = L'\0'; 550 if (nconv != (size_t)-2) { 551 if (iswspace(*wcp)) { 552 while (n != 0) { 553 n--; 554 ungetc(buf[n], 555 fp); 556 } 557 break; 558 } 559 nread += n; 560 width--; 561 if (!(flags & SUPPRESS)) 562 wcp++; 563 n = 0; 564 } 565 if (fp->_r <= 0 && __srefill(fp)) { 566 if (n != 0) { 567 fp->_flags |= __SERR; 568 goto input_failure; 569 } 570 break; 571 } 572 } 573 if (!(flags & SUPPRESS)) { 574 *wcp = L'\0'; 575 nassigned++; 576 } 577 } else 578 #endif /* SCANF_WIDE_CHAR */ 579 if (flags & SUPPRESS) { 580 n = 0; 581 while (!isspace(*fp->_p)) { 582 n++, fp->_r--, fp->_p++; 583 if (--width == 0) 584 break; 585 if (fp->_r <= 0 && __srefill(fp)) 586 break; 587 } 588 nread += n; 589 } else { 590 p0 = p = va_arg(ap, char *); 591 while (!isspace(*fp->_p)) { 592 fp->_r--; 593 *p++ = *fp->_p++; 594 if (--width == 0) 595 break; 596 if (fp->_r <= 0 && __srefill(fp)) 597 break; 598 } 599 *p = '\0'; 600 nread += p - p0; 601 nassigned++; 602 } 603 continue; 604 605 case CT_INT: 606 /* scan an integer as if by strtoimax/strtoumax */ 607 #ifdef hardway 608 if (width == 0 || width > sizeof(buf) - 1) 609 width = sizeof(buf) - 1; 610 #else 611 /* size_t is unsigned, hence this optimisation */ 612 if (--width > sizeof(buf) - 2) 613 width = sizeof(buf) - 2; 614 width++; 615 #endif 616 flags |= SIGNOK | NDIGITS | NZDIGITS; 617 for (p = buf; width; width--) { 618 c = *fp->_p; 619 /* 620 * Switch on the character; `goto ok' 621 * if we accept it as a part of number. 622 */ 623 switch (c) { 624 625 /* 626 * The digit 0 is always legal, but is 627 * special. For %i conversions, if no 628 * digits (zero or nonzero) have been 629 * scanned (only signs), we will have 630 * base==0. In that case, we should set 631 * it to 8 and enable 0x prefixing. 632 * Also, if we have not scanned zero digits 633 * before this, do not turn off prefixing 634 * (someone else will turn it off if we 635 * have scanned any nonzero digits). 636 */ 637 case '0': 638 if (base == 0) { 639 base = 8; 640 flags |= PFXOK; 641 } 642 if (flags & NZDIGITS) 643 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 644 else 645 flags &= ~(SIGNOK|PFXOK|NDIGITS); 646 goto ok; 647 648 /* 1 through 7 always legal */ 649 case '1': case '2': case '3': 650 case '4': case '5': case '6': case '7': 651 base = basefix[base]; 652 flags &= ~(SIGNOK | PFXOK | NDIGITS); 653 goto ok; 654 655 /* digits 8 and 9 ok iff decimal or hex */ 656 case '8': case '9': 657 base = basefix[base]; 658 if (base <= 8) 659 break; /* not legal here */ 660 flags &= ~(SIGNOK | PFXOK | NDIGITS); 661 goto ok; 662 663 /* letters ok iff hex */ 664 case 'A': case 'B': case 'C': 665 case 'D': case 'E': case 'F': 666 case 'a': case 'b': case 'c': 667 case 'd': case 'e': case 'f': 668 /* no need to fix base here */ 669 if (base <= 10) 670 break; /* not legal here */ 671 flags &= ~(SIGNOK | PFXOK | NDIGITS); 672 goto ok; 673 674 /* sign ok only as first character */ 675 case '+': case '-': 676 if (flags & SIGNOK) { 677 flags &= ~SIGNOK; 678 flags |= HAVESIGN; 679 goto ok; 680 } 681 break; 682 683 /* 684 * x ok iff flag still set and 2nd char (or 685 * 3rd char if we have a sign). 686 */ 687 case 'x': case 'X': 688 if ((flags & PFXOK) && p == 689 buf + 1 + !!(flags & HAVESIGN)) { 690 base = 16; /* if %i */ 691 flags &= ~PFXOK; 692 goto ok; 693 } 694 break; 695 } 696 697 /* 698 * If we got here, c is not a legal character 699 * for a number. Stop accumulating digits. 700 */ 701 break; 702 ok: 703 /* 704 * c is legal: store it and look at the next. 705 */ 706 *p++ = c; 707 if (--fp->_r > 0) 708 fp->_p++; 709 else if (__srefill(fp)) 710 break; /* EOF */ 711 } 712 /* 713 * If we had only a sign, it is no good; push 714 * back the sign. If the number ends in `x', 715 * it was [sign] '0' 'x', so push back the x 716 * and treat it as [sign] '0'. 717 */ 718 if (flags & NDIGITS) { 719 if (p > buf) 720 (void) ungetc(*(u_char *)--p, fp); 721 goto match_failure; 722 } 723 c = ((u_char *)p)[-1]; 724 if (c == 'x' || c == 'X') { 725 --p; 726 (void) ungetc(c, fp); 727 } 728 if ((flags & SUPPRESS) == 0) { 729 uintmax_t res; 730 731 *p = '\0'; 732 if (flags & UNSIGNED) 733 res = strtoumax(buf, NULL, base); 734 else 735 res = strtoimax(buf, NULL, base); 736 if (flags & POINTER) 737 *va_arg(ap, void **) = 738 (void *)(uintptr_t)res; 739 else if (flags & MAXINT) 740 *va_arg(ap, intmax_t *) = res; 741 else if (flags & LLONG) 742 *va_arg(ap, long long *) = res; 743 else if (flags & SIZEINT) 744 *va_arg(ap, ssize_t *) = res; 745 else if (flags & PTRINT) 746 *va_arg(ap, ptrdiff_t *) = res; 747 else if (flags & LONG) 748 *va_arg(ap, long *) = res; 749 else if (flags & SHORT) 750 *va_arg(ap, short *) = res; 751 else if (flags & SHORTSHORT) 752 *va_arg(ap, signed char *) = res; 753 else 754 *va_arg(ap, int *) = res; 755 nassigned++; 756 } 757 nread += p - buf; 758 break; 759 760 #ifdef FLOATING_POINT 761 case CT_FLOAT: 762 /* scan a floating point number as if by strtod */ 763 #ifdef hardway 764 if (width == 0 || width > sizeof(buf) - 1) 765 width = sizeof(buf) - 1; 766 #else 767 /* size_t is unsigned, hence this optimisation */ 768 if (--width > sizeof(buf) - 2) 769 width = sizeof(buf) - 2; 770 width++; 771 #endif 772 flags |= SIGNOK | NDIGITS | DPTOK | EXPOK; 773 for (p = buf; width; width--) { 774 c = *fp->_p; 775 /* 776 * This code mimicks the integer conversion 777 * code, but is much simpler. 778 */ 779 switch (c) { 780 781 case '0': case '1': case '2': case '3': 782 case '4': case '5': case '6': case '7': 783 case '8': case '9': 784 flags &= ~(SIGNOK | NDIGITS); 785 goto fok; 786 787 case '+': case '-': 788 if (flags & SIGNOK) { 789 flags &= ~SIGNOK; 790 goto fok; 791 } 792 break; 793 case '.': 794 if (flags & DPTOK) { 795 flags &= ~(SIGNOK | DPTOK); 796 goto fok; 797 } 798 break; 799 case 'e': case 'E': 800 /* no exponent without some digits */ 801 if ((flags&(NDIGITS|EXPOK)) == EXPOK) { 802 flags = 803 (flags & ~(EXPOK|DPTOK)) | 804 SIGNOK | NDIGITS; 805 goto fok; 806 } 807 break; 808 } 809 break; 810 fok: 811 *p++ = c; 812 if (--fp->_r > 0) 813 fp->_p++; 814 else if (__srefill(fp)) 815 break; /* EOF */ 816 } 817 /* 818 * If no digits, might be missing exponent digits 819 * (just give back the exponent) or might be missing 820 * regular digits, but had sign and/or decimal point. 821 */ 822 if (flags & NDIGITS) { 823 if (flags & EXPOK) { 824 /* no digits at all */ 825 while (p > buf) 826 ungetc(*(u_char *)--p, fp); 827 goto match_failure; 828 } 829 /* just a bad exponent (e and maybe sign) */ 830 c = *(u_char *)--p; 831 if (c != 'e' && c != 'E') { 832 (void) ungetc(c, fp);/* sign */ 833 c = *(u_char *)--p; 834 } 835 (void) ungetc(c, fp); 836 } 837 if ((flags & SUPPRESS) == 0) { 838 *p = '\0'; 839 if (flags & LONGDBL) { 840 long double res = strtold(buf, 841 (char **)NULL); 842 *va_arg(ap, long double *) = res; 843 } else if (flags & LONG) { 844 double res = strtod(buf, (char **)NULL); 845 *va_arg(ap, double *) = res; 846 } else { 847 float res = strtof(buf, (char **)NULL); 848 *va_arg(ap, float *) = res; 849 } 850 nassigned++; 851 } 852 nread += p - buf; 853 break; 854 #endif /* FLOATING_POINT */ 855 } 856 } 857 input_failure: 858 if (nassigned == 0) 859 nassigned = -1; 860 match_failure: 861 return (nassigned); 862 } 863 864 /* 865 * Fill in the given table from the scanset at the given format 866 * (just after `['). Return a pointer to the character past the 867 * closing `]'. The table has a 1 wherever characters should be 868 * considered part of the scanset. 869 */ 870 static u_char * 871 __sccl(char *tab, u_char *fmt) 872 { 873 int c, n, v; 874 875 /* first `clear' the whole table */ 876 c = *fmt++; /* first char hat => negated scanset */ 877 if (c == '^') { 878 v = 1; /* default => accept */ 879 c = *fmt++; /* get new first char */ 880 } else 881 v = 0; /* default => reject */ 882 /* should probably use memset here */ 883 for (n = 0; n < 256; n++) 884 tab[n] = v; 885 if (c == 0) 886 return (fmt - 1);/* format ended before closing ] */ 887 888 /* 889 * Now set the entries corresponding to the actual scanset 890 * to the opposite of the above. 891 * 892 * The first character may be ']' (or '-') without being special; 893 * the last character may be '-'. 894 */ 895 v = 1 - v; 896 for (;;) { 897 tab[c] = v; /* take character c */ 898 doswitch: 899 n = *fmt++; /* and examine the next */ 900 switch (n) { 901 902 case 0: /* format ended too soon */ 903 return (fmt - 1); 904 905 case '-': 906 /* 907 * A scanset of the form 908 * [01+-] 909 * is defined as `the digit 0, the digit 1, 910 * the character +, the character -', but 911 * the effect of a scanset such as 912 * [a-zA-Z0-9] 913 * is implementation defined. The V7 Unix 914 * scanf treats `a-z' as `the letters a through 915 * z', but treats `a-a' as `the letter a, the 916 * character -, and the letter a'. 917 * 918 * For compatibility, the `-' is not considerd 919 * to define a range if the character following 920 * it is either a close bracket (required by ANSI) 921 * or is not numerically greater than the character 922 * we just stored in the table (c). 923 */ 924 n = *fmt; 925 if (n == ']' || n < c) { 926 c = '-'; 927 break; /* resume the for(;;) */ 928 } 929 fmt++; 930 do { /* fill in the range */ 931 tab[++c] = v; 932 } while (c < n); 933 #if 1 /* XXX another disgusting compatibility hack */ 934 /* 935 * Alas, the V7 Unix scanf also treats formats 936 * such as [a-c-e] as `the letters a through e'. 937 * This too is permitted by the standard.... 938 */ 939 goto doswitch; 940 #else 941 c = *fmt++; 942 if (c == 0) 943 return (fmt - 1); 944 if (c == ']') 945 return (fmt); 946 #endif 947 break; 948 949 case ']': /* end of scanset */ 950 return (fmt); 951 952 default: /* just another character */ 953 c = n; 954 break; 955 } 956 } 957 /* NOTREACHED */ 958 } 959 960 int 961 vfscanf(FILE *fp, const char *fmt0, __va_list ap) 962 { 963 int r; 964 965 FLOCKFILE(fp); 966 r = __svfscanf(fp, fmt0, ap); 967 FUNLOCKFILE(fp); 968 return (r); 969 } 970
