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 defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)vfscanf.c 8.1 (Berkeley) 6/4/93"; 40 #endif 41 static const char rcsid[] = 42 "$Id: vfscanf.c,v 1.7 1997/02/22 15:02:41 peter Exp $"; 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <ctype.h> 48 #if __STDC__ 49 #include <stdarg.h> 50 #else 51 #include <varargs.h> 52 #endif 53 #include <string.h> 54 55 #include "collate.h" 56 #include "local.h" 57 58 #define FLOATING_POINT 59 60 #include "floatio.h" 61 #define BUF 513 /* Maximum length of numeric string. */ 62 63 /* 64 * Flags used during conversion. 65 */ 66 #define LONG 0x01 /* l: long or double */ 67 #define LONGDBL 0x02 /* L: long double; unimplemented */ 68 #define SHORT 0x04 /* h: short */ 69 #define SUPPRESS 0x08 /* suppress assignment */ 70 #define POINTER 0x10 /* weird %p pointer (`fake hex') */ 71 #define NOSKIP 0x20 /* do not skip blanks */ 72 73 /* 74 * The following are used in numeric conversions only: 75 * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point; 76 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral. 77 */ 78 #define SIGNOK 0x40 /* +/- is (still) legal */ 79 #define NDIGITS 0x80 /* no digits detected */ 80 81 #define DPTOK 0x100 /* (float) decimal point is still legal */ 82 #define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */ 83 84 #define PFXOK 0x100 /* 0x prefix is (still) legal */ 85 #define NZDIGITS 0x200 /* no zero digits detected */ 86 87 /* 88 * Conversion types. 89 */ 90 #define CT_CHAR 0 /* %c conversion */ 91 #define CT_CCL 1 /* %[...] conversion */ 92 #define CT_STRING 2 /* %s conversion */ 93 #define CT_INT 3 /* integer, i.e., strtol or strtoul */ 94 #define CT_FLOAT 4 /* floating, i.e., strtod */ 95 96 #define u_char unsigned char 97 #define u_long unsigned long 98 99 static u_char *__sccl(char *, u_char *); 100 101 /* 102 * vfscanf 103 */ 104 int 105 __svfscanf(fp, fmt0, ap) 106 register FILE *fp; 107 char const *fmt0; 108 va_list ap; 109 { 110 register u_char *fmt = (u_char *)fmt0; 111 register int c; /* character from format, or conversion */ 112 register size_t width; /* field width, or 0 */ 113 register char *p; /* points into all kinds of strings */ 114 register int n; /* handy integer */ 115 register int flags; /* flags as defined above */ 116 register char *p0; /* saves original value of p when necessary */ 117 int nassigned; /* number of fields assigned */ 118 int nconversions; /* number of conversions */ 119 int nread; /* number of characters consumed from fp */ 120 int base; /* base argument to strtol/strtoul */ 121 u_long (*ccfn)(); /* conversion function (strtol/strtoul) */ 122 char ccltab[256]; /* character class table for %[...] */ 123 char buf[BUF]; /* buffer for numeric conversions */ 124 125 /* `basefix' is used to avoid `if' tests in the integer scanner */ 126 static short basefix[17] = 127 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 128 129 nassigned = 0; 130 nconversions = 0; 131 nread = 0; 132 base = 0; /* XXX just to keep gcc happy */ 133 ccfn = NULL; /* XXX just to keep gcc happy */ 134 for (;;) { 135 c = *fmt++; 136 if (c == 0) 137 return (nassigned); 138 if (isspace(c)) { 139 for (;;) { 140 if (fp->_r <= 0 && __srefill(fp)) 141 goto input_failure; 142 if (!isspace(*fp->_p)) 143 break; 144 nread++, fp->_r--, fp->_p++; 145 } 146 continue; 147 } 148 if (c != '%') 149 goto literal; 150 width = 0; 151 flags = 0; 152 /* 153 * switch on the format. continue if done; 154 * break once format type is derived. 155 */ 156 again: c = *fmt++; 157 switch (c) { 158 case '%': 159 literal: 160 if (fp->_r <= 0 && __srefill(fp)) 161 goto input_failure; 162 if (*fp->_p != c) 163 goto match_failure; 164 fp->_r--, fp->_p++; 165 nread++; 166 continue; 167 168 case '*': 169 flags |= SUPPRESS; 170 goto again; 171 case 'l': 172 flags |= LONG; 173 goto again; 174 case 'L': 175 flags |= LONGDBL; 176 goto again; 177 case 'h': 178 flags |= SHORT; 179 goto again; 180 181 case '0': case '1': case '2': case '3': case '4': 182 case '5': case '6': case '7': case '8': case '9': 183 width = width * 10 + c - '0'; 184 goto again; 185 186 /* 187 * Conversions. 188 * Those marked `compat' are for 4.[123]BSD compatibility. 189 * 190 * (According to ANSI, E and X formats are supposed 191 * to the same as e and x. Sorry about that.) 192 */ 193 case 'D': /* compat */ 194 flags |= LONG; 195 /* FALLTHROUGH */ 196 case 'd': 197 c = CT_INT; 198 ccfn = (u_long (*)())strtol; 199 base = 10; 200 break; 201 202 case 'i': 203 c = CT_INT; 204 ccfn = (u_long (*)())strtol; 205 base = 0; 206 break; 207 208 case 'O': /* compat */ 209 flags |= LONG; 210 /* FALLTHROUGH */ 211 case 'o': 212 c = CT_INT; 213 ccfn = strtoul; 214 base = 8; 215 break; 216 217 case 'u': 218 c = CT_INT; 219 ccfn = strtoul; 220 base = 10; 221 break; 222 223 case 'X': /* compat XXX */ 224 flags |= LONG; 225 /* FALLTHROUGH */ 226 case 'x': 227 flags |= PFXOK; /* enable 0x prefixing */ 228 c = CT_INT; 229 ccfn = strtoul; 230 base = 16; 231 break; 232 233 #ifdef FLOATING_POINT 234 case 'E': /* compat XXX */ 235 case 'F': /* compat */ 236 flags |= LONG; 237 /* FALLTHROUGH */ 238 case 'e': case 'f': case 'g': 239 c = CT_FLOAT; 240 break; 241 #endif 242 243 case 's': 244 c = CT_STRING; 245 break; 246 247 case '[': 248 fmt = __sccl(ccltab, fmt); 249 flags |= NOSKIP; 250 c = CT_CCL; 251 break; 252 253 case 'c': 254 flags |= NOSKIP; 255 c = CT_CHAR; 256 break; 257 258 case 'p': /* pointer format is like hex */ 259 flags |= POINTER | PFXOK; 260 c = CT_INT; 261 ccfn = strtoul; 262 base = 16; 263 break; 264 265 case 'n': 266 nconversions++; 267 if (flags & SUPPRESS) /* ??? */ 268 continue; 269 if (flags & SHORT) 270 *va_arg(ap, short *) = nread; 271 else if (flags & LONG) 272 *va_arg(ap, long *) = nread; 273 else 274 *va_arg(ap, int *) = nread; 275 continue; 276 277 /* 278 * Disgusting backwards compatibility hacks. XXX 279 */ 280 case '\0': /* compat */ 281 return (EOF); 282 283 default: /* compat */ 284 if (isupper(c)) 285 flags |= LONG; 286 c = CT_INT; 287 ccfn = (u_long (*)())strtol; 288 base = 10; 289 break; 290 } 291 292 /* 293 * We have a conversion that requires input. 294 */ 295 if (fp->_r <= 0 && __srefill(fp)) 296 goto input_failure; 297 298 /* 299 * Consume leading white space, except for formats 300 * that suppress this. 301 */ 302 if ((flags & NOSKIP) == 0) { 303 while (isspace(*fp->_p)) { 304 nread++; 305 if (--fp->_r > 0) 306 fp->_p++; 307 else if (__srefill(fp)) 308 goto input_failure; 309 } 310 /* 311 * Note that there is at least one character in 312 * the buffer, so conversions that do not set NOSKIP 313 * ca no longer result in an input failure. 314 */ 315 } 316 317 /* 318 * Do the conversion. 319 */ 320 switch (c) { 321 322 case CT_CHAR: 323 /* scan arbitrary characters (sets NOSKIP) */ 324 if (width == 0) 325 width = 1; 326 if (flags & SUPPRESS) { 327 size_t sum = 0; 328 for (;;) { 329 if ((n = fp->_r) < width) { 330 sum += n; 331 width -= n; 332 fp->_p += n; 333 if (__srefill(fp)) { 334 if (sum == 0) 335 goto input_failure; 336 break; 337 } 338 } else { 339 sum += width; 340 fp->_r -= width; 341 fp->_p += width; 342 break; 343 } 344 } 345 nread += sum; 346 } else { 347 size_t r = fread((void *)va_arg(ap, char *), 1, 348 width, fp); 349 350 if (r == 0) 351 goto input_failure; 352 nread += r; 353 nassigned++; 354 } 355 nconversions++; 356 break; 357 358 case CT_CCL: 359 /* scan a (nonempty) character class (sets NOSKIP) */ 360 if (width == 0) 361 width = (size_t)~0; /* `infinity' */ 362 /* take only those things in the class */ 363 if (flags & SUPPRESS) { 364 n = 0; 365 while (ccltab[*fp->_p]) { 366 n++, fp->_r--, fp->_p++; 367 if (--width == 0) 368 break; 369 if (fp->_r <= 0 && __srefill(fp)) { 370 if (n == 0) 371 goto input_failure; 372 break; 373 } 374 } 375 if (n == 0) 376 goto match_failure; 377 } else { 378 p0 = p = va_arg(ap, char *); 379 while (ccltab[*fp->_p]) { 380 fp->_r--; 381 *p++ = *fp->_p++; 382 if (--width == 0) 383 break; 384 if (fp->_r <= 0 && __srefill(fp)) { 385 if (p == p0) 386 goto input_failure; 387 break; 388 } 389 } 390 n = p - p0; 391 if (n == 0) 392 goto match_failure; 393 *p = 0; 394 nassigned++; 395 } 396 nread += n; 397 nconversions++; 398 break; 399 400 case CT_STRING: 401 /* like CCL, but zero-length string OK, & no NOSKIP */ 402 if (width == 0) 403 width = (size_t)~0; 404 if (flags & SUPPRESS) { 405 n = 0; 406 while (!isspace(*fp->_p)) { 407 n++, fp->_r--, fp->_p++; 408 if (--width == 0) 409 break; 410 if (fp->_r <= 0 && __srefill(fp)) 411 break; 412 } 413 nread += n; 414 } else { 415 p0 = p = va_arg(ap, char *); 416 while (!isspace(*fp->_p)) { 417 fp->_r--; 418 *p++ = *fp->_p++; 419 if (--width == 0) 420 break; 421 if (fp->_r <= 0 && __srefill(fp)) 422 break; 423 } 424 *p = 0; 425 nread += p - p0; 426 nassigned++; 427 } 428 nconversions++; 429 continue; 430 431 case CT_INT: 432 /* scan an integer as if by strtol/strtoul */ 433 #ifdef hardway 434 if (width == 0 || width > sizeof(buf) - 1) 435 width = sizeof(buf) - 1; 436 #else 437 /* size_t is unsigned, hence this optimisation */ 438 if (--width > sizeof(buf) - 2) 439 width = sizeof(buf) - 2; 440 width++; 441 #endif 442 flags |= SIGNOK | NDIGITS | NZDIGITS; 443 for (p = buf; width; width--) { 444 c = *fp->_p; 445 /* 446 * Switch on the character; `goto ok' 447 * if we accept it as a part of number. 448 */ 449 switch (c) { 450 451 /* 452 * The digit 0 is always legal, but is 453 * special. For %i conversions, if no 454 * digits (zero or nonzero) have been 455 * scanned (only signs), we will have 456 * base==0. In that case, we should set 457 * it to 8 and enable 0x prefixing. 458 * Also, if we have not scanned zero digits 459 * before this, do not turn off prefixing 460 * (someone else will turn it off if we 461 * have scanned any nonzero digits). 462 */ 463 case '0': 464 if (base == 0) { 465 base = 8; 466 flags |= PFXOK; 467 } 468 if (flags & NZDIGITS) 469 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 470 else 471 flags &= ~(SIGNOK|PFXOK|NDIGITS); 472 goto ok; 473 474 /* 1 through 7 always legal */ 475 case '1': case '2': case '3': 476 case '4': case '5': case '6': case '7': 477 base = basefix[base]; 478 flags &= ~(SIGNOK | PFXOK | NDIGITS); 479 goto ok; 480 481 /* digits 8 and 9 ok iff decimal or hex */ 482 case '8': case '9': 483 base = basefix[base]; 484 if (base <= 8) 485 break; /* not legal here */ 486 flags &= ~(SIGNOK | PFXOK | NDIGITS); 487 goto ok; 488 489 /* letters ok iff hex */ 490 case 'A': case 'B': case 'C': 491 case 'D': case 'E': case 'F': 492 case 'a': case 'b': case 'c': 493 case 'd': case 'e': case 'f': 494 /* no need to fix base here */ 495 if (base <= 10) 496 break; /* not legal here */ 497 flags &= ~(SIGNOK | PFXOK | NDIGITS); 498 goto ok; 499 500 /* sign ok only as first character */ 501 case '+': case '-': 502 if (flags & SIGNOK) { 503 flags &= ~SIGNOK; 504 goto ok; 505 } 506 break; 507 508 /* x ok iff flag still set & 2nd char */ 509 case 'x': case 'X': 510 if (flags & PFXOK && p == buf + 1) { 511 base = 16; /* if %i */ 512 flags &= ~PFXOK; 513 goto ok; 514 } 515 break; 516 } 517 518 /* 519 * If we got here, c is not a legal character 520 * for a number. Stop accumulating digits. 521 */ 522 break; 523 ok: 524 /* 525 * c is legal: store it and look at the next. 526 */ 527 *p++ = c; 528 if (--fp->_r > 0) 529 fp->_p++; 530 else if (__srefill(fp)) 531 break; /* EOF */ 532 } 533 /* 534 * If we had only a sign, it is no good; push 535 * back the sign. If the number ends in `x', 536 * it was [sign] '0' 'x', so push back the x 537 * and treat it as [sign] '0'. 538 */ 539 if (flags & NDIGITS) { 540 if (p > buf) 541 (void) ungetc(*(u_char *)--p, fp); 542 goto match_failure; 543 } 544 c = ((u_char *)p)[-1]; 545 if (c == 'x' || c == 'X') { 546 --p; 547 (void) ungetc(c, fp); 548 } 549 if ((flags & SUPPRESS) == 0) { 550 u_long res; 551 552 *p = 0; 553 res = (*ccfn)(buf, (char **)NULL, base); 554 if (flags & POINTER) 555 *va_arg(ap, void **) = (void *)res; 556 else if (flags & SHORT) 557 *va_arg(ap, short *) = res; 558 else if (flags & LONG) 559 *va_arg(ap, long *) = res; 560 else 561 *va_arg(ap, int *) = res; 562 nassigned++; 563 } 564 nread += p - buf; 565 nconversions++; 566 break; 567 568 #ifdef FLOATING_POINT 569 case CT_FLOAT: 570 /* scan a floating point number as if by strtod */ 571 #ifdef hardway 572 if (width == 0 || width > sizeof(buf) - 1) 573 width = sizeof(buf) - 1; 574 #else 575 /* size_t is unsigned, hence this optimisation */ 576 if (--width > sizeof(buf) - 2) 577 width = sizeof(buf) - 2; 578 width++; 579 #endif 580 flags |= SIGNOK | NDIGITS | DPTOK | EXPOK; 581 for (p = buf; width; width--) { 582 c = *fp->_p; 583 /* 584 * This code mimicks the integer conversion 585 * code, but is much simpler. 586 */ 587 switch (c) { 588 589 case '0': case '1': case '2': case '3': 590 case '4': case '5': case '6': case '7': 591 case '8': case '9': 592 flags &= ~(SIGNOK | NDIGITS); 593 goto fok; 594 595 case '+': case '-': 596 if (flags & SIGNOK) { 597 flags &= ~SIGNOK; 598 goto fok; 599 } 600 break; 601 case '.': 602 if (flags & DPTOK) { 603 flags &= ~(SIGNOK | DPTOK); 604 goto fok; 605 } 606 break; 607 case 'e': case 'E': 608 /* no exponent without some digits */ 609 if ((flags&(NDIGITS|EXPOK)) == EXPOK) { 610 flags = 611 (flags & ~(EXPOK|DPTOK)) | 612 SIGNOK | NDIGITS; 613 goto fok; 614 } 615 break; 616 } 617 break; 618 fok: 619 *p++ = c; 620 if (--fp->_r > 0) 621 fp->_p++; 622 else if (__srefill(fp)) 623 break; /* EOF */ 624 } 625 /* 626 * If no digits, might be missing exponent digits 627 * (just give back the exponent) or might be missing 628 * regular digits, but had sign and/or decimal point. 629 */ 630 if (flags & NDIGITS) { 631 if (flags & EXPOK) { 632 /* no digits at all */ 633 while (p > buf) 634 ungetc(*(u_char *)--p, fp); 635 goto match_failure; 636 } 637 /* just a bad exponent (e and maybe sign) */ 638 c = *(u_char *)--p; 639 if (c != 'e' && c != 'E') { 640 (void) ungetc(c, fp);/* sign */ 641 c = *(u_char *)--p; 642 } 643 (void) ungetc(c, fp); 644 } 645 if ((flags & SUPPRESS) == 0) { 646 double res; 647 648 *p = 0; 649 res = strtod(buf,(char **) NULL); 650 if (flags & LONG) 651 *va_arg(ap, double *) = res; 652 else 653 *va_arg(ap, float *) = res; 654 nassigned++; 655 } 656 nread += p - buf; 657 nconversions++; 658 break; 659 #endif /* FLOATING_POINT */ 660 } 661 } 662 input_failure: 663 return (nconversions != 0 ? nassigned : EOF); 664 match_failure: 665 return (nassigned); 666 } 667 668 /* 669 * Fill in the given table from the scanset at the given format 670 * (just after `['). Return a pointer to the character past the 671 * closing `]'. The table has a 1 wherever characters should be 672 * considered part of the scanset. 673 */ 674 static u_char * 675 __sccl(tab, fmt) 676 register char *tab; 677 register u_char *fmt; 678 { 679 register int c, n, v, i; 680 681 /* first `clear' the whole table */ 682 c = *fmt++; /* first char hat => negated scanset */ 683 if (c == '^') { 684 v = 1; /* default => accept */ 685 c = *fmt++; /* get new first char */ 686 } else 687 v = 0; /* default => reject */ 688 689 /* XXX: Will not work if sizeof(tab*) > sizeof(char) */ 690 (void) memset(tab, v, 256); 691 692 if (c == 0) 693 return (fmt - 1);/* format ended before closing ] */ 694 695 /* 696 * Now set the entries corresponding to the actual scanset 697 * to the opposite of the above. 698 * 699 * The first character may be ']' (or '-') without being special; 700 * the last character may be '-'. 701 */ 702 v = 1 - v; 703 for (;;) { 704 tab[c] = v; /* take character c */ 705 doswitch: 706 n = *fmt++; /* and examine the next */ 707 switch (n) { 708 709 case 0: /* format ended too soon */ 710 return (fmt - 1); 711 712 case '-': 713 /* 714 * A scanset of the form 715 * [01+-] 716 * is defined as `the digit 0, the digit 1, 717 * the character +, the character -', but 718 * the effect of a scanset such as 719 * [a-zA-Z0-9] 720 * is implementation defined. The V7 Unix 721 * scanf treats `a-z' as `the letters a through 722 * z', but treats `a-a' as `the letter a, the 723 * character -, and the letter a'. 724 * 725 * For compatibility, the `-' is not considerd 726 * to define a range if the character following 727 * it is either a close bracket (required by ANSI) 728 * or is not numerically greater than the character 729 * we just stored in the table (c). 730 */ 731 n = *fmt; 732 if (n == ']' || __collate_range_cmp (n, c) < 0) { 733 c = '-'; 734 break; /* resume the for(;;) */ 735 } 736 fmt++; 737 /* fill in the range */ 738 for (i = 0; i < 256; i ++) 739 if ( __collate_range_cmp (c, i) < 0 740 && __collate_range_cmp (i, n) <= 0 741 ) 742 tab[i] = v; 743 #if 1 /* XXX another disgusting compatibility hack */ 744 c = n; 745 /* 746 * Alas, the V7 Unix scanf also treats formats 747 * such as [a-c-e] as `the letters a through e'. 748 * This too is permitted by the standard.... 749 */ 750 goto doswitch; 751 #else 752 c = *fmt++; 753 if (c == 0) 754 return (fmt - 1); 755 if (c == ']') 756 return (fmt); 757 #endif 758 break; 759 760 case ']': /* end of scanset */ 761 return (fmt); 762 763 default: /* just another character */ 764 c = n; 765 break; 766 } 767 } 768 /* NOTREACHED */ 769 } 770