1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Chris Torek. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #if 0 38 #if defined(LIBC_SCCS) && !defined(lint) 39 static char sccsid[] = "@(#)vfscanf.c 8.1 (Berkeley) 6/4/93"; 40 #endif /* LIBC_SCCS and not lint */ 41 #endif 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include "namespace.h" 46 #include <ctype.h> 47 #include <inttypes.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <stddef.h> 51 #include <stdarg.h> 52 #include <string.h> 53 #include <wchar.h> 54 #include <wctype.h> 55 #include "un-namespace.h" 56 57 #include "libc_private.h" 58 #include "local.h" 59 60 #ifndef NO_FLOATING_POINT 61 #include <locale.h> 62 #endif 63 64 #define BUF 513 /* Maximum length of numeric string. */ 65 66 /* 67 * Flags used during conversion. 68 */ 69 #define LONG 0x01 /* l: long or double */ 70 #define LONGDBL 0x02 /* L: long double */ 71 #define SHORT 0x04 /* h: short */ 72 #define SUPPRESS 0x08 /* *: suppress assignment */ 73 #define POINTER 0x10 /* p: void * (as hex) */ 74 #define NOSKIP 0x20 /* [ or c: do not skip blanks */ 75 #define LONGLONG 0x400 /* ll: long long (+ deprecated q: quad) */ 76 #define INTMAXT 0x800 /* j: intmax_t */ 77 #define PTRDIFFT 0x1000 /* t: ptrdiff_t */ 78 #define SIZET 0x2000 /* z: size_t */ 79 #define SHORTSHORT 0x4000 /* hh: char */ 80 #define UNSIGNED 0x8000 /* %[oupxX] conversions */ 81 82 /* 83 * The following are used in integral conversions only: 84 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS 85 */ 86 #define SIGNOK 0x40 /* +/- is (still) legal */ 87 #define NDIGITS 0x80 /* no digits detected */ 88 #define PFXOK 0x100 /* 0x prefix is (still) legal */ 89 #define NZDIGITS 0x200 /* no zero digits detected */ 90 #define HAVESIGN 0x10000 /* sign detected */ 91 92 /* 93 * Conversion types. 94 */ 95 #define CT_CHAR 0 /* %c conversion */ 96 #define CT_CCL 1 /* %[...] conversion */ 97 #define CT_STRING 2 /* %s conversion */ 98 #define CT_INT 3 /* %[dioupxX] conversion */ 99 #define CT_FLOAT 4 /* %[efgEFG] conversion */ 100 101 static int parsefloat(FILE *, wchar_t *, wchar_t *); 102 103 extern int __scanfdebug; 104 105 #define INCCL(_c) \ 106 (cclcompl ? (wmemchr(ccls, (_c), ccle - ccls) == NULL) : \ 107 (wmemchr(ccls, (_c), ccle - ccls) != NULL)) 108 109 /* 110 * MT-safe version. 111 */ 112 int 113 vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap) 114 { 115 int ret; 116 117 FLOCKFILE(fp); 118 ORIENT(fp, 1); 119 ret = __vfwscanf(fp, fmt, ap); 120 FUNLOCKFILE(fp); 121 return (ret); 122 } 123 124 /* 125 * Non-MT-safe version. 126 */ 127 int 128 __vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap) 129 { 130 wint_t c; /* character from format, or conversion */ 131 size_t width; /* field width, or 0 */ 132 wchar_t *p; /* points into all kinds of strings */ 133 int n; /* handy integer */ 134 int flags; /* flags as defined above */ 135 wchar_t *p0; /* saves original value of p when necessary */ 136 int nassigned; /* number of fields assigned */ 137 int nconversions; /* number of conversions */ 138 int nread; /* number of characters consumed from fp */ 139 int base; /* base argument to conversion function */ 140 wchar_t buf[BUF]; /* buffer for numeric conversions */ 141 const wchar_t *ccls; /* character class start */ 142 const wchar_t *ccle; /* character class end */ 143 int cclcompl; /* ccl is complemented? */ 144 wint_t wi; /* handy wint_t */ 145 char *mbp; /* multibyte string pointer for %c %s %[ */ 146 size_t nconv; /* number of bytes in mb. conversion */ 147 char mbbuf[MB_LEN_MAX]; /* temporary mb. character buffer */ 148 static const mbstate_t initial; 149 mbstate_t mbs; 150 151 /* `basefix' is used to avoid `if' tests in the integer scanner */ 152 static short basefix[17] = 153 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 154 155 nassigned = 0; 156 nconversions = 0; 157 nread = 0; 158 ccls = ccle = NULL; 159 for (;;) { 160 c = *fmt++; 161 if (c == 0) 162 return (nassigned); 163 if (iswspace(c)) { 164 while ((c = __fgetwc(fp)) != WEOF && 165 iswspace(c)) 166 ; 167 if (c != WEOF) 168 __ungetwc(c, fp); 169 continue; 170 } 171 if (c != '%') 172 goto literal; 173 width = 0; 174 flags = 0; 175 /* 176 * switch on the format. continue if done; 177 * break once format type is derived. 178 */ 179 again: c = *fmt++; 180 switch (c) { 181 case '%': 182 literal: 183 if ((wi = __fgetwc(fp)) == WEOF) 184 goto input_failure; 185 if (wi != c) { 186 __ungetwc(wi, fp); 187 goto input_failure; 188 } 189 nread++; 190 continue; 191 192 case '*': 193 flags |= SUPPRESS; 194 goto again; 195 case 'j': 196 flags |= INTMAXT; 197 goto again; 198 case 'l': 199 if (flags & LONG) { 200 flags &= ~LONG; 201 flags |= LONGLONG; 202 } else 203 flags |= LONG; 204 goto again; 205 case 'q': 206 flags |= LONGLONG; /* not quite */ 207 goto again; 208 case 't': 209 flags |= PTRDIFFT; 210 goto again; 211 case 'z': 212 flags |= SIZET; 213 goto again; 214 case 'L': 215 flags |= LONGDBL; 216 goto again; 217 case 'h': 218 if (flags & SHORT) { 219 flags &= ~SHORT; 220 flags |= SHORTSHORT; 221 } else 222 flags |= SHORT; 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 */ 233 case 'd': 234 c = CT_INT; 235 base = 10; 236 break; 237 238 case 'i': 239 c = CT_INT; 240 base = 0; 241 break; 242 243 case 'o': 244 c = CT_INT; 245 flags |= UNSIGNED; 246 base = 8; 247 break; 248 249 case 'u': 250 c = CT_INT; 251 flags |= UNSIGNED; 252 base = 10; 253 break; 254 255 case 'X': 256 case 'x': 257 flags |= PFXOK; /* enable 0x prefixing */ 258 c = CT_INT; 259 flags |= UNSIGNED; 260 base = 16; 261 break; 262 263 #ifndef NO_FLOATING_POINT 264 case 'A': case 'E': case 'F': case 'G': 265 case 'a': case 'e': case 'f': case 'g': 266 c = CT_FLOAT; 267 break; 268 #endif 269 270 case 'S': 271 flags |= LONG; 272 /* FALLTHROUGH */ 273 case 's': 274 c = CT_STRING; 275 break; 276 277 case '[': 278 ccls = fmt; 279 if (*fmt == '^') { 280 cclcompl = 1; 281 fmt++; 282 } else 283 cclcompl = 0; 284 if (*fmt == ']') 285 fmt++; 286 while (*fmt != '\0' && *fmt != ']') 287 fmt++; 288 ccle = fmt; 289 fmt++; 290 flags |= NOSKIP; 291 c = CT_CCL; 292 break; 293 294 case 'C': 295 flags |= LONG; 296 /* FALLTHROUGH */ 297 case 'c': 298 flags |= NOSKIP; 299 c = CT_CHAR; 300 break; 301 302 case 'p': /* pointer format is like hex */ 303 flags |= POINTER | PFXOK; 304 c = CT_INT; /* assumes sizeof(uintmax_t) */ 305 flags |= UNSIGNED; /* >= sizeof(uintptr_t) */ 306 base = 16; 307 break; 308 309 case 'n': 310 nconversions++; 311 if (flags & SUPPRESS) /* ??? */ 312 continue; 313 if (flags & SHORTSHORT) 314 *va_arg(ap, char *) = nread; 315 else if (flags & SHORT) 316 *va_arg(ap, short *) = nread; 317 else if (flags & LONG) 318 *va_arg(ap, long *) = nread; 319 else if (flags & LONGLONG) 320 *va_arg(ap, long long *) = nread; 321 else if (flags & INTMAXT) 322 *va_arg(ap, intmax_t *) = nread; 323 else if (flags & SIZET) 324 *va_arg(ap, size_t *) = nread; 325 else if (flags & PTRDIFFT) 326 *va_arg(ap, ptrdiff_t *) = nread; 327 else 328 *va_arg(ap, int *) = nread; 329 continue; 330 331 default: 332 goto match_failure; 333 334 /* 335 * Disgusting backwards compatibility hack. XXX 336 */ 337 case '\0': /* compat */ 338 return (EOF); 339 } 340 341 /* 342 * Consume leading white space, except for formats 343 * that suppress this. 344 */ 345 if ((flags & NOSKIP) == 0) { 346 while ((wi = __fgetwc(fp)) != WEOF && iswspace(wi)) 347 nread++; 348 if (wi == WEOF) 349 goto input_failure; 350 __ungetwc(wi, fp); 351 } 352 353 /* 354 * Do the conversion. 355 */ 356 switch (c) { 357 358 case CT_CHAR: 359 /* scan arbitrary characters (sets NOSKIP) */ 360 if (width == 0) 361 width = 1; 362 if (flags & LONG) { 363 if (!(flags & SUPPRESS)) 364 p = va_arg(ap, wchar_t *); 365 n = 0; 366 while (width-- != 0 && 367 (wi = __fgetwc(fp)) != WEOF) { 368 if (!(flags & SUPPRESS)) 369 *p++ = (wchar_t)wi; 370 n++; 371 } 372 if (n == 0) 373 goto input_failure; 374 nread += n; 375 if (!(flags & SUPPRESS)) 376 nassigned++; 377 } else { 378 if (!(flags & SUPPRESS)) 379 mbp = va_arg(ap, char *); 380 n = 0; 381 mbs = initial; 382 while (width != 0 && 383 (wi = __fgetwc(fp)) != WEOF) { 384 if (width >= MB_CUR_MAX && 385 !(flags & SUPPRESS)) { 386 nconv = wcrtomb(mbp, wi, &mbs); 387 if (nconv == (size_t)-1) 388 goto input_failure; 389 } else { 390 nconv = wcrtomb(mbbuf, wi, 391 &mbs); 392 if (nconv == (size_t)-1) 393 goto input_failure; 394 if (nconv > width) { 395 __ungetwc(wi, fp); 396 break; 397 } 398 if (!(flags & SUPPRESS)) 399 memcpy(mbp, mbbuf, 400 nconv); 401 } 402 if (!(flags & SUPPRESS)) 403 mbp += nconv; 404 width -= nconv; 405 n++; 406 } 407 if (n == 0) 408 goto input_failure; 409 nread += n; 410 if (!(flags & SUPPRESS)) 411 nassigned++; 412 } 413 nconversions++; 414 break; 415 416 case CT_CCL: 417 /* scan a (nonempty) character class (sets NOSKIP) */ 418 if (width == 0) 419 width = (size_t)~0; /* `infinity' */ 420 /* take only those things in the class */ 421 if ((flags & SUPPRESS) && (flags & LONG)) { 422 n = 0; 423 while ((wi = __fgetwc(fp)) != WEOF && 424 width-- != 0 && INCCL(wi)) 425 n++; 426 if (wi != WEOF) 427 __ungetwc(wi, fp); 428 if (n == 0) 429 goto match_failure; 430 } else if (flags & LONG) { 431 p0 = p = va_arg(ap, wchar_t *); 432 while ((wi = __fgetwc(fp)) != WEOF && 433 width-- != 0 && INCCL(wi)) 434 *p++ = (wchar_t)wi; 435 if (wi != WEOF) 436 __ungetwc(wi, fp); 437 n = p - p0; 438 if (n == 0) 439 goto match_failure; 440 *p = 0; 441 nassigned++; 442 } else { 443 if (!(flags & SUPPRESS)) 444 mbp = va_arg(ap, char *); 445 n = 0; 446 mbs = initial; 447 while ((wi = __fgetwc(fp)) != WEOF && 448 width != 0 && INCCL(wi)) { 449 if (width >= MB_CUR_MAX && 450 !(flags & SUPPRESS)) { 451 nconv = wcrtomb(mbp, wi, &mbs); 452 if (nconv == (size_t)-1) 453 goto input_failure; 454 } else { 455 nconv = wcrtomb(mbbuf, wi, 456 &mbs); 457 if (nconv == (size_t)-1) 458 goto input_failure; 459 if (nconv > width) 460 break; 461 if (!(flags & SUPPRESS)) 462 memcpy(mbp, mbbuf, 463 nconv); 464 } 465 if (!(flags & SUPPRESS)) 466 mbp += nconv; 467 width -= nconv; 468 n++; 469 } 470 if (wi != WEOF) 471 __ungetwc(wi, fp); 472 if (!(flags & SUPPRESS)) { 473 *mbp = 0; 474 nassigned++; 475 } 476 } 477 nread += n; 478 nconversions++; 479 break; 480 481 case CT_STRING: 482 /* like CCL, but zero-length string OK, & no NOSKIP */ 483 if (width == 0) 484 width = (size_t)~0; 485 if ((flags & SUPPRESS) && (flags & LONG)) { 486 while ((wi = __fgetwc(fp)) != WEOF && 487 width-- != 0 && 488 !iswspace(wi)) 489 nread++; 490 if (wi != WEOF) 491 __ungetwc(wi, fp); 492 } else if (flags & LONG) { 493 p0 = p = va_arg(ap, wchar_t *); 494 while ((wi = __fgetwc(fp)) != WEOF && 495 width-- != 0 && 496 !iswspace(wi)) { 497 *p++ = (wchar_t)wi; 498 nread++; 499 } 500 if (wi != WEOF) 501 __ungetwc(wi, fp); 502 *p = '\0'; 503 nassigned++; 504 } else { 505 if (!(flags & SUPPRESS)) 506 mbp = va_arg(ap, char *); 507 mbs = initial; 508 while ((wi = __fgetwc(fp)) != WEOF && 509 width != 0 && 510 !iswspace(wi)) { 511 if (width >= MB_CUR_MAX && 512 !(flags & SUPPRESS)) { 513 nconv = wcrtomb(mbp, wi, &mbs); 514 if (nconv == (size_t)-1) 515 goto input_failure; 516 } else { 517 nconv = wcrtomb(mbbuf, wi, 518 &mbs); 519 if (nconv == (size_t)-1) 520 goto input_failure; 521 if (nconv > width) 522 break; 523 if (!(flags & SUPPRESS)) 524 memcpy(mbp, mbbuf, 525 nconv); 526 } 527 if (!(flags & SUPPRESS)) 528 mbp += nconv; 529 width -= nconv; 530 nread++; 531 } 532 if (wi != WEOF) 533 __ungetwc(wi, fp); 534 if (!(flags & SUPPRESS)) { 535 *mbp = 0; 536 nassigned++; 537 } 538 } 539 nconversions++; 540 continue; 541 542 case CT_INT: 543 /* scan an integer as if by the conversion function */ 544 if (width == 0 || width > sizeof(buf) / 545 sizeof(*buf) - 1) 546 width = sizeof(buf) / sizeof(*buf) - 1; 547 flags |= SIGNOK | NDIGITS | NZDIGITS; 548 for (p = buf; width; width--) { 549 c = __fgetwc(fp); 550 /* 551 * Switch on the character; `goto ok' 552 * if we accept it as a part of number. 553 */ 554 switch (c) { 555 556 /* 557 * The digit 0 is always legal, but is 558 * special. For %i conversions, if no 559 * digits (zero or nonzero) have been 560 * scanned (only signs), we will have 561 * base==0. In that case, we should set 562 * it to 8 and enable 0x prefixing. 563 * Also, if we have not scanned zero digits 564 * before this, do not turn off prefixing 565 * (someone else will turn it off if we 566 * have scanned any nonzero digits). 567 */ 568 case '0': 569 if (base == 0) { 570 base = 8; 571 flags |= PFXOK; 572 } 573 if (flags & NZDIGITS) 574 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 575 else 576 flags &= ~(SIGNOK|PFXOK|NDIGITS); 577 goto ok; 578 579 /* 1 through 7 always legal */ 580 case '1': case '2': case '3': 581 case '4': case '5': case '6': case '7': 582 base = basefix[base]; 583 flags &= ~(SIGNOK | PFXOK | NDIGITS); 584 goto ok; 585 586 /* digits 8 and 9 ok iff decimal or hex */ 587 case '8': case '9': 588 base = basefix[base]; 589 if (base <= 8) 590 break; /* not legal here */ 591 flags &= ~(SIGNOK | PFXOK | NDIGITS); 592 goto ok; 593 594 /* letters ok iff hex */ 595 case 'A': case 'B': case 'C': 596 case 'D': case 'E': case 'F': 597 case 'a': case 'b': case 'c': 598 case 'd': case 'e': case 'f': 599 /* no need to fix base here */ 600 if (base <= 10) 601 break; /* not legal here */ 602 flags &= ~(SIGNOK | PFXOK | NDIGITS); 603 goto ok; 604 605 /* sign ok only as first character */ 606 case '+': case '-': 607 if (flags & SIGNOK) { 608 flags &= ~SIGNOK; 609 flags |= HAVESIGN; 610 goto ok; 611 } 612 break; 613 614 /* 615 * x ok iff flag still set & 2nd char (or 616 * 3rd char if we have a sign). 617 */ 618 case 'x': case 'X': 619 if (flags & PFXOK && p == 620 buf + 1 + !!(flags & HAVESIGN)) { 621 base = 16; /* if %i */ 622 flags &= ~PFXOK; 623 goto ok; 624 } 625 break; 626 } 627 628 /* 629 * If we got here, c is not a legal character 630 * for a number. Stop accumulating digits. 631 */ 632 if (c != WEOF) 633 __ungetwc(c, fp); 634 break; 635 ok: 636 /* 637 * c is legal: store it and look at the next. 638 */ 639 *p++ = (wchar_t)c; 640 } 641 /* 642 * If we had only a sign, it is no good; push 643 * back the sign. If the number ends in `x', 644 * it was [sign] '0' 'x', so push back the x 645 * and treat it as [sign] '0'. 646 */ 647 if (flags & NDIGITS) { 648 if (p > buf) 649 __ungetwc(*--p, fp); 650 goto match_failure; 651 } 652 c = p[-1]; 653 if (c == 'x' || c == 'X') { 654 --p; 655 __ungetwc(c, fp); 656 } 657 if ((flags & SUPPRESS) == 0) { 658 uintmax_t res; 659 660 *p = 0; 661 if ((flags & UNSIGNED) == 0) 662 res = wcstoimax(buf, NULL, base); 663 else 664 res = wcstoumax(buf, NULL, base); 665 if (flags & POINTER) 666 *va_arg(ap, void **) = 667 (void *)(uintptr_t)res; 668 else if (flags & SHORTSHORT) 669 *va_arg(ap, char *) = res; 670 else if (flags & SHORT) 671 *va_arg(ap, short *) = res; 672 else if (flags & LONG) 673 *va_arg(ap, long *) = res; 674 else if (flags & LONGLONG) 675 *va_arg(ap, long long *) = res; 676 else if (flags & INTMAXT) 677 *va_arg(ap, intmax_t *) = res; 678 else if (flags & PTRDIFFT) 679 *va_arg(ap, ptrdiff_t *) = res; 680 else if (flags & SIZET) 681 *va_arg(ap, size_t *) = res; 682 else 683 *va_arg(ap, int *) = res; 684 nassigned++; 685 } 686 nread += p - buf; 687 nconversions++; 688 break; 689 690 #ifndef NO_FLOATING_POINT 691 case CT_FLOAT: 692 /* scan a floating point number as if by strtod */ 693 if (width == 0 || width > sizeof(buf) / 694 sizeof(*buf) - 1) 695 width = sizeof(buf) / sizeof(*buf) - 1; 696 if ((width = parsefloat(fp, buf, buf + width)) == 0) 697 goto match_failure; 698 if ((flags & SUPPRESS) == 0) { 699 if (flags & LONGDBL) { 700 long double res = wcstold(buf, &p); 701 *va_arg(ap, long double *) = res; 702 } else if (flags & LONG) { 703 double res = wcstod(buf, &p); 704 *va_arg(ap, double *) = res; 705 } else { 706 float res = wcstof(buf, &p); 707 *va_arg(ap, float *) = res; 708 } 709 if (__scanfdebug && p - buf != width) 710 abort(); 711 nassigned++; 712 } 713 nread += width; 714 nconversions++; 715 break; 716 #endif /* !NO_FLOATING_POINT */ 717 } 718 } 719 input_failure: 720 return (nconversions != 0 ? nassigned : EOF); 721 match_failure: 722 return (nassigned); 723 } 724 725 #ifndef NO_FLOATING_POINT 726 static int 727 parsefloat(FILE *fp, wchar_t *buf, wchar_t *end) 728 { 729 wchar_t *commit, *p; 730 int infnanpos = 0; 731 enum { 732 S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX, 733 S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS 734 } state = S_START; 735 wchar_t c; 736 wchar_t decpt = (wchar_t)(unsigned char)*localeconv()->decimal_point; 737 _Bool gotmantdig = 0, ishex = 0; 738 739 /* 740 * We set commit = p whenever the string we have read so far 741 * constitutes a valid representation of a floating point 742 * number by itself. At some point, the parse will complete 743 * or fail, and we will ungetc() back to the last commit point. 744 * To ensure that the file offset gets updated properly, it is 745 * always necessary to read at least one character that doesn't 746 * match; thus, we can't short-circuit "infinity" or "nan(...)". 747 */ 748 commit = buf - 1; 749 c = WEOF; 750 for (p = buf; p < end; ) { 751 if ((c = __fgetwc(fp)) == WEOF) 752 break; 753 reswitch: 754 switch (state) { 755 case S_START: 756 state = S_GOTSIGN; 757 if (c == '-' || c == '+') 758 break; 759 else 760 goto reswitch; 761 case S_GOTSIGN: 762 switch (c) { 763 case '0': 764 state = S_MAYBEHEX; 765 commit = p; 766 break; 767 case 'I': 768 case 'i': 769 state = S_INF; 770 break; 771 case 'N': 772 case 'n': 773 state = S_NAN; 774 break; 775 default: 776 state = S_DIGITS; 777 goto reswitch; 778 } 779 break; 780 case S_INF: 781 if (infnanpos > 6 || 782 (c != "nfinity"[infnanpos] && 783 c != "NFINITY"[infnanpos])) 784 goto parsedone; 785 if (infnanpos == 1 || infnanpos == 6) 786 commit = p; /* inf or infinity */ 787 infnanpos++; 788 break; 789 case S_NAN: 790 switch (infnanpos) { 791 case -1: /* XXX kludge to deal with nan(...) */ 792 goto parsedone; 793 case 0: 794 if (c != 'A' && c != 'a') 795 goto parsedone; 796 break; 797 case 1: 798 if (c != 'N' && c != 'n') 799 goto parsedone; 800 else 801 commit = p; 802 break; 803 case 2: 804 if (c != '(') 805 goto parsedone; 806 break; 807 default: 808 if (c == ')') { 809 commit = p; 810 infnanpos = -2; 811 } else if (!iswalnum(c) && c != '_') 812 goto parsedone; 813 break; 814 } 815 infnanpos++; 816 break; 817 case S_MAYBEHEX: 818 state = S_DIGITS; 819 if (c == 'X' || c == 'x') { 820 ishex = 1; 821 break; 822 } else { /* we saw a '0', but no 'x' */ 823 gotmantdig = 1; 824 goto reswitch; 825 } 826 case S_DIGITS: 827 if ((ishex && iswxdigit(c)) || iswdigit(c)) 828 gotmantdig = 1; 829 else { 830 state = S_FRAC; 831 if (c != decpt) 832 goto reswitch; 833 } 834 if (gotmantdig) 835 commit = p; 836 break; 837 case S_FRAC: 838 if (((c == 'E' || c == 'e') && !ishex) || 839 ((c == 'P' || c == 'p') && ishex)) { 840 if (!gotmantdig) 841 goto parsedone; 842 else 843 state = S_EXP; 844 } else if ((ishex && iswxdigit(c)) || iswdigit(c)) { 845 commit = p; 846 gotmantdig = 1; 847 } else 848 goto parsedone; 849 break; 850 case S_EXP: 851 state = S_EXPDIGITS; 852 if (c == '-' || c == '+') 853 break; 854 else 855 goto reswitch; 856 case S_EXPDIGITS: 857 if (iswdigit(c)) 858 commit = p; 859 else 860 goto parsedone; 861 break; 862 default: 863 abort(); 864 } 865 *p++ = c; 866 c = WEOF; 867 } 868 869 parsedone: 870 if (c != WEOF) 871 __ungetwc(c, fp); 872 while (commit < --p) 873 __ungetwc(*p, fp); 874 *++commit = '\0'; 875 return (commit - buf); 876 } 877 #endif 878