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