vfwscanf.c revision 1.2
1 /* $NetBSD: vfwscanf.c,v 1.2 2005/06/12 05:48:41 lukem Exp $ */ 2 3 /*- 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 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)ftell.c 8.2 (Berkeley) 5/4/95"; 43 __FBSDID("$FreeBSD: src/lib/libc/stdio/vfwscanf.c,v 1.12 2004/05/02 20:13:29 obrien Exp $"); 44 #else 45 __RCSID("$NetBSD: vfwscanf.c,v 1.2 2005/06/12 05:48:41 lukem Exp $"); 46 #endif 47 #endif /* LIBC_SCCS and not lint */ 48 49 #include "namespace.h" 50 #include <ctype.h> 51 #include <inttypes.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <stddef.h> 55 #include <stdarg.h> 56 #include <string.h> 57 #include <limits.h> 58 #include <wchar.h> 59 #include <wctype.h> 60 61 #include "reentrant.h" 62 #include "local.h" 63 64 #ifndef NO_FLOATING_POINT 65 #include <locale.h> 66 #endif 67 68 #define BUF 513 /* Maximum length of numeric string. */ 69 70 /* 71 * Flags used during conversion. 72 */ 73 #define LONG 0x01 /* l: long or double */ 74 #define LONGDBL 0x02 /* L: long double */ 75 #define SHORT 0x04 /* h: short */ 76 #define SUPPRESS 0x08 /* *: suppress assignment */ 77 #define POINTER 0x10 /* p: void * (as hex) */ 78 #define NOSKIP 0x20 /* [ or c: do not skip blanks */ 79 #define LONGLONG 0x400 /* ll: quad_t (+ deprecated q: quad) */ 80 #define INTMAXT 0x800 /* j: intmax_t */ 81 #define PTRDIFFT 0x1000 /* t: ptrdiff_t */ 82 #define SIZET 0x2000 /* z: size_t */ 83 #define SHORTSHORT 0x4000 /* hh: char */ 84 #define UNSIGNED 0x8000 /* %[oupxX] conversions */ 85 86 /* 87 * The following are used in integral conversions only: 88 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS 89 */ 90 #define SIGNOK 0x40 /* +/- is (still) legal */ 91 #define NDIGITS 0x80 /* no digits detected */ 92 #define PFXOK 0x100 /* 0x prefix is (still) legal */ 93 #define NZDIGITS 0x200 /* no zero digits detected */ 94 #define HAVESIGN 0x10000 /* sign detected */ 95 96 /* 97 * Conversion types. 98 */ 99 #define CT_CHAR 0 /* %c conversion */ 100 #define CT_CCL 1 /* %[...] conversion */ 101 #define CT_STRING 2 /* %s conversion */ 102 #define CT_INT 3 /* %[dioupxX] conversion */ 103 #define CT_FLOAT 4 /* %[efgEFG] conversion */ 104 105 static int parsefloat(FILE *, wchar_t *, wchar_t *); 106 107 #define INCCL(_c) \ 108 (cclcompl ? (wmemchr(ccls, (_c), (size_t)(ccle - ccls)) == NULL) : \ 109 (wmemchr(ccls, (_c), (size_t)(ccle - ccls)) != NULL)) 110 111 /* 112 * MT-safe version. 113 */ 114 int 115 vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap) 116 { 117 int ret; 118 119 FLOCKFILE(fp); 120 _SET_ORIENTATION(fp, 1); 121 ret = __vfwscanf_unlocked(fp, fmt, ap); 122 FUNLOCKFILE(fp); 123 return (ret); 124 } 125 126 /* 127 * Non-MT-safe version. 128 */ 129 int 130 __vfwscanf_unlocked(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap) 131 { 132 wint_t c; /* character from format, or conversion */ 133 size_t width; /* field width, or 0 */ 134 wchar_t *p; /* points into all kinds of strings */ 135 int n; /* handy integer */ 136 int flags; /* flags as defined above */ 137 wchar_t *p0; /* saves original value of p when necessary */ 138 int nassigned; /* number of fields assigned */ 139 int nconversions; /* number of conversions */ 140 int nread; /* number of characters consumed from fp */ 141 int base; /* base argument to conversion function */ 142 wchar_t buf[BUF]; /* buffer for numeric conversions */ 143 const wchar_t *ccls; /* character class start */ 144 const wchar_t *ccle; /* character class end */ 145 int cclcompl; /* ccl is complemented? */ 146 wint_t wi; /* handy wint_t */ 147 char *mbp; /* multibyte string pointer for %c %s %[ */ 148 size_t nconv; /* number of bytes in mb. conversion */ 149 char mbbuf[MB_LEN_MAX]; /* temporary mb. character buffer */ 150 static const mbstate_t initial; 151 mbstate_t mbs; 152 153 /* `basefix' is used to avoid `if' tests in the integer scanner */ 154 static short basefix[17] = 155 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 156 157 nassigned = 0; 158 nconversions = 0; 159 nread = 0; 160 ccls = ccle = NULL; 161 base = 0; 162 cclcompl = 0; 163 mbp = NULL; 164 for (;;) { 165 c = *fmt++; 166 if (c == 0) 167 return (nassigned); 168 if (iswspace(c)) { 169 while ((c = __fgetwc_unlock(fp)) != WEOF && 170 iswspace(c)) 171 ; 172 if (c != WEOF) 173 ungetwc(c, fp); 174 continue; 175 } 176 if (c != '%') 177 goto literal; 178 width = 0; 179 flags = 0; 180 /* 181 * switch on the format. continue if done; 182 * break once format type is derived. 183 */ 184 again: c = *fmt++; 185 switch (c) { 186 case '%': 187 literal: 188 if ((wi = __fgetwc_unlock(fp)) == WEOF) 189 goto input_failure; 190 if (wi != c) { 191 ungetwc(wi, fp); 192 goto input_failure; 193 } 194 nread++; 195 continue; 196 197 case '*': 198 flags |= SUPPRESS; 199 goto again; 200 case 'j': 201 flags |= INTMAXT; 202 goto again; 203 case 'l': 204 if (flags & LONG) { 205 flags &= ~LONG; 206 flags |= LONGLONG; 207 } else 208 flags |= LONG; 209 goto again; 210 case 'q': 211 flags |= LONGLONG; /* not quite */ 212 goto again; 213 case 't': 214 flags |= PTRDIFFT; 215 goto again; 216 case 'z': 217 flags |= SIZET; 218 goto again; 219 case 'L': 220 flags |= LONGDBL; 221 goto again; 222 case 'h': 223 if (flags & SHORT) { 224 flags &= ~SHORT; 225 flags |= SHORTSHORT; 226 } else 227 flags |= SHORT; 228 goto again; 229 230 case '0': case '1': case '2': case '3': case '4': 231 case '5': case '6': case '7': case '8': case '9': 232 width = width * 10 + c - '0'; 233 goto again; 234 235 /* 236 * Conversions. 237 */ 238 case 'd': 239 c = CT_INT; 240 base = 10; 241 break; 242 243 case 'i': 244 c = CT_INT; 245 base = 0; 246 break; 247 248 case 'o': 249 c = CT_INT; 250 flags |= UNSIGNED; 251 base = 8; 252 break; 253 254 case 'u': 255 c = CT_INT; 256 flags |= UNSIGNED; 257 base = 10; 258 break; 259 260 case 'X': 261 case 'x': 262 flags |= PFXOK; /* enable 0x prefixing */ 263 c = CT_INT; 264 flags |= UNSIGNED; 265 base = 16; 266 break; 267 268 #ifndef NO_FLOATING_POINT 269 case 'A': case 'E': case 'F': case 'G': 270 case 'a': case 'e': case 'f': case 'g': 271 c = CT_FLOAT; 272 break; 273 #endif 274 275 case 'S': 276 flags |= LONG; 277 /* FALLTHROUGH */ 278 case 's': 279 c = CT_STRING; 280 break; 281 282 case '[': 283 ccls = fmt; 284 if (*fmt == '^') { 285 cclcompl = 1; 286 fmt++; 287 } else 288 cclcompl = 0; 289 if (*fmt == ']') 290 fmt++; 291 while (*fmt != '\0' && *fmt != ']') 292 fmt++; 293 ccle = fmt; 294 fmt++; 295 flags |= NOSKIP; 296 c = CT_CCL; 297 break; 298 299 case 'C': 300 flags |= LONG; 301 /* FALLTHROUGH */ 302 case 'c': 303 flags |= NOSKIP; 304 c = CT_CHAR; 305 break; 306 307 case 'p': /* pointer format is like hex */ 308 flags |= POINTER | PFXOK; 309 c = CT_INT; /* assumes sizeof(uintmax_t) */ 310 flags |= UNSIGNED; /* >= sizeof(uintptr_t) */ 311 base = 16; 312 break; 313 314 case 'n': 315 nconversions++; 316 if (flags & SUPPRESS) /* ??? */ 317 continue; 318 if (flags & SHORTSHORT) 319 *va_arg(ap, char *) = nread; 320 else if (flags & SHORT) 321 *va_arg(ap, short *) = nread; 322 else if (flags & LONG) 323 *va_arg(ap, long *) = nread; 324 else if (flags & LONGLONG) 325 *va_arg(ap, quad_t *) = nread; 326 else if (flags & INTMAXT) 327 *va_arg(ap, intmax_t *) = nread; 328 else if (flags & SIZET) 329 *va_arg(ap, size_t *) = nread; 330 else if (flags & PTRDIFFT) 331 *va_arg(ap, ptrdiff_t *) = nread; 332 else 333 *va_arg(ap, int *) = nread; 334 continue; 335 336 default: 337 goto match_failure; 338 339 /* 340 * Disgusting backwards compatibility hack. XXX 341 */ 342 case '\0': /* compat */ 343 return (EOF); 344 } 345 346 /* 347 * Consume leading white space, except for formats 348 * that suppress this. 349 */ 350 if ((flags & NOSKIP) == 0) { 351 while ((wi = __fgetwc_unlock(fp)) != WEOF && iswspace(wi)) 352 nread++; 353 if (wi == WEOF) 354 goto input_failure; 355 ungetwc(wi, fp); 356 } 357 358 /* 359 * Do the conversion. 360 */ 361 switch (c) { 362 363 case CT_CHAR: 364 /* scan arbitrary characters (sets NOSKIP) */ 365 if (width == 0) 366 width = 1; 367 if (flags & LONG) { 368 if (!(flags & SUPPRESS)) 369 p = va_arg(ap, wchar_t *); 370 n = 0; 371 while (width-- != 0 && 372 (wi = __fgetwc_unlock(fp)) != WEOF) { 373 if (!(flags & SUPPRESS)) 374 *p++ = (wchar_t)wi; 375 n++; 376 } 377 if (n == 0) 378 goto input_failure; 379 nread += n; 380 if (!(flags & SUPPRESS)) 381 nassigned++; 382 } else { 383 if (!(flags & SUPPRESS)) 384 mbp = va_arg(ap, char *); 385 n = 0; 386 mbs = initial; 387 while (width != 0 && 388 (wi = __fgetwc_unlock(fp)) != WEOF) { 389 if (width >= MB_CUR_MAX && 390 !(flags & SUPPRESS)) { 391 nconv = wcrtomb(mbp, wi, &mbs); 392 if (nconv == (size_t)-1) 393 goto input_failure; 394 } else { 395 nconv = wcrtomb(mbbuf, wi, 396 &mbs); 397 if (nconv == (size_t)-1) 398 goto input_failure; 399 if (nconv > width) { 400 ungetwc(wi, fp); 401 break; 402 } 403 if (!(flags & SUPPRESS)) 404 memcpy(mbp, mbbuf, 405 nconv); 406 } 407 if (!(flags & SUPPRESS)) 408 mbp += nconv; 409 width -= nconv; 410 n++; 411 } 412 if (n == 0) 413 goto input_failure; 414 nread += n; 415 if (!(flags & SUPPRESS)) 416 nassigned++; 417 } 418 nconversions++; 419 break; 420 421 case CT_CCL: 422 /* scan a (nonempty) character class (sets NOSKIP) */ 423 if (width == 0) 424 width = (size_t)~0; /* `infinity' */ 425 /* take only those things in the class */ 426 if ((flags & SUPPRESS) && (flags & LONG)) { 427 n = 0; 428 while ((wi = __fgetwc_unlock(fp)) != WEOF && 429 width-- != 0 && INCCL(wi)) 430 n++; 431 if (wi != WEOF) 432 ungetwc(wi, fp); 433 if (n == 0) 434 goto match_failure; 435 } else if (flags & LONG) { 436 p0 = p = va_arg(ap, wchar_t *); 437 while ((wi = __fgetwc_unlock(fp)) != WEOF && 438 width-- != 0 && INCCL(wi)) 439 *p++ = (wchar_t)wi; 440 if (wi != WEOF) 441 ungetwc(wi, fp); 442 n = p - p0; 443 if (n == 0) 444 goto match_failure; 445 *p = 0; 446 nassigned++; 447 } else { 448 if (!(flags & SUPPRESS)) 449 mbp = va_arg(ap, char *); 450 n = 0; 451 mbs = initial; 452 while ((wi = __fgetwc_unlock(fp)) != WEOF && 453 width != 0 && INCCL(wi)) { 454 if (width >= MB_CUR_MAX && 455 !(flags & SUPPRESS)) { 456 nconv = wcrtomb(mbp, wi, &mbs); 457 if (nconv == (size_t)-1) 458 goto input_failure; 459 } else { 460 nconv = wcrtomb(mbbuf, wi, 461 &mbs); 462 if (nconv == (size_t)-1) 463 goto input_failure; 464 if (nconv > width) 465 break; 466 if (!(flags & SUPPRESS)) 467 memcpy(mbp, mbbuf, 468 nconv); 469 } 470 if (!(flags & SUPPRESS)) 471 mbp += nconv; 472 width -= nconv; 473 n++; 474 } 475 if (wi != WEOF) 476 ungetwc(wi, fp); 477 if (!(flags & SUPPRESS)) { 478 *mbp = 0; 479 nassigned++; 480 } 481 } 482 nread += n; 483 nconversions++; 484 break; 485 486 case CT_STRING: 487 /* like CCL, but zero-length string OK, & no NOSKIP */ 488 if (width == 0) 489 width = (size_t)~0; 490 if ((flags & SUPPRESS) && (flags & LONG)) { 491 while ((wi = __fgetwc_unlock(fp)) != WEOF && 492 width-- != 0 && 493 !iswspace(wi)) 494 nread++; 495 if (wi != WEOF) 496 ungetwc(wi, fp); 497 } else if (flags & LONG) { 498 p0 = p = va_arg(ap, wchar_t *); 499 while ((wi = __fgetwc_unlock(fp)) != WEOF && 500 width-- != 0 && 501 !iswspace(wi)) { 502 *p++ = (wchar_t)wi; 503 nread++; 504 } 505 if (wi != WEOF) 506 ungetwc(wi, fp); 507 *p = '\0'; 508 nassigned++; 509 } else { 510 if (!(flags & SUPPRESS)) 511 mbp = va_arg(ap, char *); 512 mbs = initial; 513 while ((wi = __fgetwc_unlock(fp)) != WEOF && 514 width != 0 && 515 !iswspace(wi)) { 516 if (width >= MB_CUR_MAX && 517 !(flags & SUPPRESS)) { 518 nconv = wcrtomb(mbp, wi, &mbs); 519 if (nconv == (size_t)-1) 520 goto input_failure; 521 } else { 522 nconv = wcrtomb(mbbuf, wi, 523 &mbs); 524 if (nconv == (size_t)-1) 525 goto input_failure; 526 if (nconv > width) 527 break; 528 if (!(flags & SUPPRESS)) 529 memcpy(mbp, mbbuf, 530 nconv); 531 } 532 if (!(flags & SUPPRESS)) 533 mbp += nconv; 534 width -= nconv; 535 nread++; 536 } 537 if (wi != WEOF) 538 ungetwc(wi, fp); 539 if (!(flags & SUPPRESS)) { 540 *mbp = 0; 541 nassigned++; 542 } 543 } 544 nconversions++; 545 continue; 546 547 case CT_INT: 548 /* scan an integer as if by the conversion function */ 549 if (width == 0 || width > sizeof(buf) / 550 sizeof(*buf) - 1) 551 width = sizeof(buf) / sizeof(*buf) - 1; 552 flags |= SIGNOK | NDIGITS | NZDIGITS; 553 for (p = buf; width; width--) { 554 c = __fgetwc_unlock(fp); 555 /* 556 * Switch on the character; `goto ok' 557 * if we accept it as a part of number. 558 */ 559 switch (c) { 560 561 /* 562 * The digit 0 is always legal, but is 563 * special. For %i conversions, if no 564 * digits (zero or nonzero) have been 565 * scanned (only signs), we will have 566 * base==0. In that case, we should set 567 * it to 8 and enable 0x prefixing. 568 * Also, if we have not scanned zero digits 569 * before this, do not turn off prefixing 570 * (someone else will turn it off if we 571 * have scanned any nonzero digits). 572 */ 573 case '0': 574 if (base == 0) { 575 base = 8; 576 flags |= PFXOK; 577 } 578 if (flags & NZDIGITS) 579 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 580 else 581 flags &= ~(SIGNOK|PFXOK|NDIGITS); 582 goto ok; 583 584 /* 1 through 7 always legal */ 585 case '1': case '2': case '3': 586 case '4': case '5': case '6': case '7': 587 base = basefix[base]; 588 flags &= ~(SIGNOK | PFXOK | NDIGITS); 589 goto ok; 590 591 /* digits 8 and 9 ok iff decimal or hex */ 592 case '8': case '9': 593 base = basefix[base]; 594 if (base <= 8) 595 break; /* not legal here */ 596 flags &= ~(SIGNOK | PFXOK | NDIGITS); 597 goto ok; 598 599 /* letters ok iff hex */ 600 case 'A': case 'B': case 'C': 601 case 'D': case 'E': case 'F': 602 case 'a': case 'b': case 'c': 603 case 'd': case 'e': case 'f': 604 /* no need to fix base here */ 605 if (base <= 10) 606 break; /* not legal here */ 607 flags &= ~(SIGNOK | PFXOK | NDIGITS); 608 goto ok; 609 610 /* sign ok only as first character */ 611 case '+': case '-': 612 if (flags & SIGNOK) { 613 flags &= ~SIGNOK; 614 flags |= HAVESIGN; 615 goto ok; 616 } 617 break; 618 619 /* 620 * x ok iff flag still set & 2nd char (or 621 * 3rd char if we have a sign). 622 */ 623 case 'x': case 'X': 624 if (flags & PFXOK && p == 625 buf + 1 + !!(flags & HAVESIGN)) { 626 base = 16; /* if %i */ 627 flags &= ~PFXOK; 628 goto ok; 629 } 630 break; 631 } 632 633 /* 634 * If we got here, c is not a legal character 635 * for a number. Stop accumulating digits. 636 */ 637 if (c != WEOF) 638 ungetwc(c, fp); 639 break; 640 ok: 641 /* 642 * c is legal: store it and look at the next. 643 */ 644 *p++ = (wchar_t)c; 645 } 646 /* 647 * If we had only a sign, it is no good; push 648 * back the sign. If the number ends in `x', 649 * it was [sign] '0' 'x', so push back the x 650 * and treat it as [sign] '0'. 651 */ 652 if (flags & NDIGITS) { 653 if (p > buf) 654 ungetwc(*--p, fp); 655 goto match_failure; 656 } 657 c = p[-1]; 658 if (c == 'x' || c == 'X') { 659 --p; 660 ungetwc(c, fp); 661 } 662 if ((flags & SUPPRESS) == 0) { 663 uintmax_t res; 664 665 *p = 0; 666 if ((flags & UNSIGNED) == 0) 667 res = wcstoimax(buf, NULL, base); 668 else 669 res = wcstoumax(buf, NULL, base); 670 if (flags & POINTER) 671 *va_arg(ap, void **) = 672 (void *)(uintptr_t)res; 673 else if (flags & SHORTSHORT) 674 *va_arg(ap, char *) = (char)res; 675 else if (flags & SHORT) 676 *va_arg(ap, short *) = (short)res; 677 else if (flags & LONG) 678 *va_arg(ap, long *) = (long)res; 679 else if (flags & LONGLONG) 680 *va_arg(ap, quad_t *) = res; 681 else if (flags & INTMAXT) 682 *va_arg(ap, intmax_t *) = res; 683 else if (flags & PTRDIFFT) 684 *va_arg(ap, ptrdiff_t *) = (ptrdiff_t)res; 685 else if (flags & SIZET) 686 *va_arg(ap, size_t *) = (size_t)res; 687 else 688 *va_arg(ap, int *) = (int)res; 689 nassigned++; 690 } 691 nread += p - buf; 692 nconversions++; 693 break; 694 695 #ifndef NO_FLOATING_POINT 696 case CT_FLOAT: 697 /* scan a floating point number as if by strtod */ 698 if (width == 0 || width > sizeof(buf) / 699 sizeof(*buf) - 1) 700 width = sizeof(buf) / sizeof(*buf) - 1; 701 if ((width = parsefloat(fp, buf, buf + width)) == 0) 702 goto match_failure; 703 if ((flags & SUPPRESS) == 0) { 704 #ifdef notyet 705 if (flags & LONGDBL) { 706 long double res = wcstold(buf, &p); 707 *va_arg(ap, long double *) = res; 708 } else 709 #endif 710 if (flags & LONG) { 711 double res = wcstod(buf, &p); 712 *va_arg(ap, double *) = res; 713 #ifdef notyet 714 } else { 715 float res = wcstof(buf, &p); 716 *va_arg(ap, float *) = res; 717 #endif 718 } 719 #ifdef DEBUG 720 if (p - buf != width) 721 abort(); 722 #endif 723 nassigned++; 724 } 725 nread += width; 726 nconversions++; 727 break; 728 #endif /* !NO_FLOATING_POINT */ 729 } 730 } 731 input_failure: 732 return (nconversions != 0 ? nassigned : EOF); 733 match_failure: 734 return (nassigned); 735 } 736 737 #ifndef NO_FLOATING_POINT 738 static int 739 parsefloat(FILE *fp, wchar_t *buf, wchar_t *end) 740 { 741 wchar_t *commit, *p; 742 int infnanpos = 0; 743 enum { 744 S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX, 745 S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS 746 } state = S_START; 747 wchar_t c; 748 wchar_t decpt = (wchar_t)(unsigned char)*localeconv()->decimal_point; 749 int gotmantdig = 0, ishex = 0; 750 751 /* 752 * We set commit = p whenever the string we have read so far 753 * constitutes a valid representation of a floating point 754 * number by itself. At some point, the parse will complete 755 * or fail, and we will ungetc() back to the last commit point. 756 * To ensure that the file offset gets updated properly, it is 757 * always necessary to read at least one character that doesn't 758 * match; thus, we can't short-circuit "infinity" or "nan(...)". 759 */ 760 commit = buf - 1; 761 c = WEOF; 762 for (p = buf; p < end; ) { 763 if ((c = __fgetwc_unlock(fp)) == WEOF) 764 break; 765 reswitch: 766 switch (state) { 767 case S_START: 768 state = S_GOTSIGN; 769 if (c == '-' || c == '+') 770 break; 771 else 772 goto reswitch; 773 case S_GOTSIGN: 774 switch (c) { 775 case '0': 776 state = S_MAYBEHEX; 777 commit = p; 778 break; 779 case 'I': 780 case 'i': 781 state = S_INF; 782 break; 783 case 'N': 784 case 'n': 785 state = S_NAN; 786 break; 787 default: 788 state = S_DIGITS; 789 goto reswitch; 790 } 791 break; 792 case S_INF: 793 if (infnanpos > 6 || 794 (c != "nfinity"[infnanpos] && 795 c != "NFINITY"[infnanpos])) 796 goto parsedone; 797 if (infnanpos == 1 || infnanpos == 6) 798 commit = p; /* inf or infinity */ 799 infnanpos++; 800 break; 801 case S_NAN: 802 switch (infnanpos) { 803 case -1: /* XXX kludge to deal with nan(...) */ 804 goto parsedone; 805 case 0: 806 if (c != 'A' && c != 'a') 807 goto parsedone; 808 break; 809 case 1: 810 if (c != 'N' && c != 'n') 811 goto parsedone; 812 else 813 commit = p; 814 break; 815 case 2: 816 if (c != '(') 817 goto parsedone; 818 break; 819 default: 820 if (c == ')') { 821 commit = p; 822 infnanpos = -2; 823 } else if (!iswalnum(c) && c != '_') 824 goto parsedone; 825 break; 826 } 827 infnanpos++; 828 break; 829 case S_MAYBEHEX: 830 state = S_DIGITS; 831 if (c == 'X' || c == 'x') { 832 ishex = 1; 833 break; 834 } else { /* we saw a '0', but no 'x' */ 835 gotmantdig = 1; 836 goto reswitch; 837 } 838 case S_DIGITS: 839 if ((ishex && iswxdigit(c)) || iswdigit(c)) 840 gotmantdig = 1; 841 else { 842 state = S_FRAC; 843 if (c != decpt) 844 goto reswitch; 845 } 846 if (gotmantdig) 847 commit = p; 848 break; 849 case S_FRAC: 850 if (((c == 'E' || c == 'e') && !ishex) || 851 ((c == 'P' || c == 'p') && ishex)) { 852 if (!gotmantdig) 853 goto parsedone; 854 else 855 state = S_EXP; 856 } else if ((ishex && iswxdigit(c)) || iswdigit(c)) { 857 commit = p; 858 gotmantdig = 1; 859 } else 860 goto parsedone; 861 break; 862 case S_EXP: 863 state = S_EXPDIGITS; 864 if (c == '-' || c == '+') 865 break; 866 else 867 goto reswitch; 868 case S_EXPDIGITS: 869 if (iswdigit(c)) 870 commit = p; 871 else 872 goto parsedone; 873 break; 874 default: 875 abort(); 876 } 877 *p++ = c; 878 c = WEOF; 879 } 880 881 parsedone: 882 if (c != WEOF) 883 ungetwc(c, fp); 884 while (commit < --p) 885 ungetwc(*p, fp); 886 *++commit = '\0'; 887 return (commit - buf); 888 } 889 #endif 890
Indexes created Mon Sep 22 05:09:51 GMT 2025