1 /* $NetBSD: vfscanf.c,v 1.14 1995/03/22 00:57:02 jtc 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 #if defined(LIBC_SCCS) && !defined(lint) 40 #if 0 41 static char sccsid[] = "@(#)vfscanf.c 8.1 (Berkeley) 6/4/93"; 42 #endif 43 static char rcsid[] = "$NetBSD: vfscanf.c,v 1.14 1995/03/22 00:57:02 jtc Exp $"; 44 #endif /* LIBC_SCCS and not lint */ 45 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <ctype.h> 49 #if __STDC__ 50 #include <stdarg.h> 51 #else 52 #include <varargs.h> 53 #endif 54 #include "local.h" 55 56 #ifdef FLOATING_POINT 57 #include "floatio.h" 58 #endif 59 60 #define BUF 513 /* Maximum length of numeric string. */ 61 62 /* 63 * Flags used during conversion. 64 */ 65 #define LONG 0x01 /* l: long or double */ 66 #define LONGDBL 0x02 /* L: long double; unimplemented */ 67 #define SHORT 0x04 /* h: short */ 68 #define QUAD 0x08 /* q: quad */ 69 #define SUPPRESS 0x10 /* suppress assignment */ 70 #define POINTER 0x20 /* weird %p pointer (`fake hex') */ 71 #define NOSKIP 0x40 /* 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 0x080 /* +/- is (still) legal */ 79 #define NDIGITS 0x100 /* no digits detected */ 80 81 #define DPTOK 0x200 /* (float) decimal point is still legal */ 82 #define EXPOK 0x400 /* (float) exponent (e+3, etc) still legal */ 83 84 #define PFXOK 0x200 /* 0x prefix is (still) legal */ 85 #define NZDIGITS 0x400 /* 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., strtoq or strtouq */ 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(); 100 101 /* 102 * vfscanf 103 */ 104 __svfscanf(fp, fmt0, ap) 105 register FILE *fp; 106 char const *fmt0; 107 _BSD_VA_LIST_ ap; 108 { 109 register u_char *fmt = (u_char *)fmt0; 110 register int c; /* character from format, or conversion */ 111 register size_t width; /* field width, or 0 */ 112 register char *p; /* points into all kinds of strings */ 113 register int n; /* handy integer */ 114 register int flags; /* flags as defined above */ 115 register char *p0; /* saves original value of p when necessary */ 116 int nassigned; /* number of fields assigned */ 117 int nread; /* number of characters consumed from fp */ 118 int base; /* base argument to strtoq/strtouq */ 119 u_quad_t (*ccfn)(); /* conversion function (strtoq/strtouq) */ 120 char ccltab[256]; /* character class table for %[...] */ 121 char buf[BUF]; /* buffer for numeric conversions */ 122 123 /* `basefix' is used to avoid `if' tests in the integer scanner */ 124 static short basefix[17] = 125 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 126 127 nassigned = 0; 128 nread = 0; 129 base = 0; /* XXX just to keep gcc happy */ 130 ccfn = NULL; /* XXX just to keep gcc happy */ 131 for (;;) { 132 c = *fmt++; 133 if (c == 0) 134 return (nassigned); 135 if (isspace(c)) { 136 for (;;) { 137 if (fp->_r <= 0 && __srefill(fp)) 138 return (nassigned); 139 if (!isspace(*fp->_p)) 140 break; 141 nread++, fp->_r--, fp->_p++; 142 } 143 continue; 144 } 145 if (c != '%') 146 goto literal; 147 width = 0; 148 flags = 0; 149 /* 150 * switch on the format. continue if done; 151 * break once format type is derived. 152 */ 153 again: c = *fmt++; 154 switch (c) { 155 case '%': 156 literal: 157 if (fp->_r <= 0 && __srefill(fp)) 158 goto input_failure; 159 if (*fp->_p != c) 160 goto match_failure; 161 fp->_r--, fp->_p++; 162 nread++; 163 continue; 164 165 case '*': 166 flags |= SUPPRESS; 167 goto again; 168 case 'L': 169 flags |= LONGDBL; 170 goto again; 171 case 'h': 172 flags |= SHORT; 173 goto again; 174 case 'l': 175 if (*fmt == 'l') { 176 fmt++; 177 flags |= QUAD; 178 } else { 179 flags |= LONG; 180 } 181 goto again; 182 case 'q': 183 flags |= QUAD; 184 goto again; 185 186 case '0': case '1': case '2': case '3': case '4': 187 case '5': case '6': case '7': case '8': case '9': 188 width = width * 10 + c - '0'; 189 goto again; 190 191 /* 192 * Conversions. 193 * Those marked `compat' are for 4.[123]BSD compatibility. 194 * 195 * (According to ANSI, E and X formats are supposed 196 * to the same as e and x. Sorry about that.) 197 */ 198 case 'D': /* compat */ 199 flags |= LONG; 200 /* FALLTHROUGH */ 201 case 'd': 202 c = CT_INT; 203 ccfn = (u_quad_t (*)())strtoq; 204 base = 10; 205 break; 206 207 case 'i': 208 c = CT_INT; 209 ccfn = (u_quad_t (*)())strtoq; 210 base = 0; 211 break; 212 213 case 'O': /* compat */ 214 flags |= LONG; 215 /* FALLTHROUGH */ 216 case 'o': 217 c = CT_INT; 218 ccfn = strtouq; 219 base = 8; 220 break; 221 222 case 'u': 223 c = CT_INT; 224 ccfn = strtouq; 225 base = 10; 226 break; 227 228 case 'X': 229 case 'x': 230 flags |= PFXOK; /* enable 0x prefixing */ 231 c = CT_INT; 232 ccfn = strtouq; 233 base = 16; 234 break; 235 236 #ifdef FLOATING_POINT 237 case 'E': 238 case 'G': 239 case 'e': 240 case 'f': 241 case 'g': 242 c = CT_FLOAT; 243 break; 244 #endif 245 246 case 's': 247 c = CT_STRING; 248 break; 249 250 case '[': 251 fmt = __sccl(ccltab, fmt); 252 flags |= NOSKIP; 253 c = CT_CCL; 254 break; 255 256 case 'c': 257 flags |= NOSKIP; 258 c = CT_CHAR; 259 break; 260 261 case 'p': /* pointer format is like hex */ 262 flags |= POINTER | PFXOK; 263 c = CT_INT; 264 ccfn = strtouq; 265 base = 16; 266 break; 267 268 case 'n': 269 if (flags & SUPPRESS) /* ??? */ 270 continue; 271 if (flags & SHORT) 272 *va_arg(ap, short *) = nread; 273 else if (flags & LONG) 274 *va_arg(ap, long *) = nread; 275 else 276 *va_arg(ap, int *) = nread; 277 continue; 278 279 /* 280 * Disgusting backwards compatibility hacks. XXX 281 */ 282 case '\0': /* compat */ 283 return (EOF); 284 285 default: /* compat */ 286 if (isupper(c)) 287 flags |= LONG; 288 c = CT_INT; 289 ccfn = (u_quad_t (*)())strtoq; 290 base = 10; 291 break; 292 } 293 294 /* 295 * We have a conversion that requires input. 296 */ 297 if (fp->_r <= 0 && __srefill(fp)) 298 goto input_failure; 299 300 /* 301 * Consume leading white space, except for formats 302 * that suppress this. 303 */ 304 if ((flags & NOSKIP) == 0) { 305 while (isspace(*fp->_p)) { 306 nread++; 307 if (--fp->_r > 0) 308 fp->_p++; 309 else if (__srefill(fp)) 310 goto input_failure; 311 } 312 /* 313 * Note that there is at least one character in 314 * the buffer, so conversions that do not set NOSKIP 315 * ca no longer result in an input failure. 316 */ 317 } 318 319 /* 320 * Do the conversion. 321 */ 322 switch (c) { 323 324 case CT_CHAR: 325 /* scan arbitrary characters (sets NOSKIP) */ 326 if (width == 0) 327 width = 1; 328 if (flags & SUPPRESS) { 329 size_t sum = 0; 330 for (;;) { 331 if ((n = fp->_r) < width) { 332 sum += n; 333 width -= n; 334 fp->_p += n; 335 if (__srefill(fp)) { 336 if (sum == 0) 337 goto input_failure; 338 break; 339 } 340 } else { 341 sum += width; 342 fp->_r -= width; 343 fp->_p += width; 344 break; 345 } 346 } 347 nread += sum; 348 } else { 349 size_t r = fread((void *)va_arg(ap, char *), 1, 350 width, fp); 351 352 if (r == 0) 353 goto input_failure; 354 nread += r; 355 nassigned++; 356 } 357 break; 358 359 case CT_CCL: 360 /* scan a (nonempty) character class (sets NOSKIP) */ 361 if (width == 0) 362 width = ~0; /* `infinity' */ 363 /* take only those things in the class */ 364 if (flags & SUPPRESS) { 365 n = 0; 366 while (ccltab[*fp->_p]) { 367 n++, fp->_r--, fp->_p++; 368 if (--width == 0) 369 break; 370 if (fp->_r <= 0 && __srefill(fp)) { 371 if (n == 0) 372 goto input_failure; 373 break; 374 } 375 } 376 if (n == 0) 377 goto match_failure; 378 } else { 379 p0 = p = va_arg(ap, char *); 380 while (ccltab[*fp->_p]) { 381 fp->_r--; 382 *p++ = *fp->_p++; 383 if (--width == 0) 384 break; 385 if (fp->_r <= 0 && __srefill(fp)) { 386 if (p == p0) 387 goto input_failure; 388 break; 389 } 390 } 391 n = p - p0; 392 if (n == 0) 393 goto match_failure; 394 *p = 0; 395 nassigned++; 396 } 397 nread += n; 398 break; 399 400 case CT_STRING: 401 /* like CCL, but zero-length string OK, & no NOSKIP */ 402 if (width == 0) 403 width = ~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 continue; 429 430 case CT_INT: 431 /* scan an integer as if by strtoq/strtouq */ 432 #ifdef hardway 433 if (width == 0 || width > sizeof(buf) - 1) 434 width = sizeof(buf) - 1; 435 #else 436 /* size_t is unsigned, hence this optimisation */ 437 if (--width > sizeof(buf) - 2) 438 width = sizeof(buf) - 2; 439 width++; 440 #endif 441 flags |= SIGNOK | NDIGITS | NZDIGITS; 442 for (p = buf; width; width--) { 443 c = *fp->_p; 444 /* 445 * Switch on the character; `goto ok' 446 * if we accept it as a part of number. 447 */ 448 switch (c) { 449 450 /* 451 * The digit 0 is always legal, but is 452 * special. For %i conversions, if no 453 * digits (zero or nonzero) have been 454 * scanned (only signs), we will have 455 * base==0. In that case, we should set 456 * it to 8 and enable 0x prefixing. 457 * Also, if we have not scanned zero digits 458 * before this, do not turn off prefixing 459 * (someone else will turn it off if we 460 * have scanned any nonzero digits). 461 */ 462 case '0': 463 if (base == 0) { 464 base = 8; 465 flags |= PFXOK; 466 } 467 if (flags & NZDIGITS) 468 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 469 else 470 flags &= ~(SIGNOK|PFXOK|NDIGITS); 471 goto ok; 472 473 /* 1 through 7 always legal */ 474 case '1': case '2': case '3': 475 case '4': case '5': case '6': case '7': 476 base = basefix[base]; 477 flags &= ~(SIGNOK | PFXOK | NDIGITS); 478 goto ok; 479 480 /* digits 8 and 9 ok iff decimal or hex */ 481 case '8': case '9': 482 base = basefix[base]; 483 if (base <= 8) 484 break; /* not legal here */ 485 flags &= ~(SIGNOK | PFXOK | NDIGITS); 486 goto ok; 487 488 /* letters ok iff hex */ 489 case 'A': case 'B': case 'C': 490 case 'D': case 'E': case 'F': 491 case 'a': case 'b': case 'c': 492 case 'd': case 'e': case 'f': 493 /* no need to fix base here */ 494 if (base <= 10) 495 break; /* not legal here */ 496 flags &= ~(SIGNOK | PFXOK | NDIGITS); 497 goto ok; 498 499 /* sign ok only as first character */ 500 case '+': case '-': 501 if (flags & SIGNOK) { 502 flags &= ~SIGNOK; 503 goto ok; 504 } 505 break; 506 507 /* x ok iff flag still set & 2nd char */ 508 case 'x': case 'X': 509 if (flags & PFXOK && p == buf + 1) { 510 base = 16; /* if %i */ 511 flags &= ~PFXOK; 512 goto ok; 513 } 514 break; 515 } 516 517 /* 518 * If we got here, c is not a legal character 519 * for a number. Stop accumulating digits. 520 */ 521 break; 522 ok: 523 /* 524 * c is legal: store it and look at the next. 525 */ 526 *p++ = c; 527 if (--fp->_r > 0) 528 fp->_p++; 529 else if (__srefill(fp)) 530 break; /* EOF */ 531 } 532 /* 533 * If we had only a sign, it is no good; push 534 * back the sign. If the number ends in `x', 535 * it was [sign] '0' 'x', so push back the x 536 * and treat it as [sign] '0'. 537 */ 538 if (flags & NDIGITS) { 539 if (p > buf) 540 (void) ungetc(*(u_char *)--p, fp); 541 goto match_failure; 542 } 543 c = ((u_char *)p)[-1]; 544 if (c == 'x' || c == 'X') { 545 --p; 546 (void) ungetc(c, fp); 547 } 548 if ((flags & SUPPRESS) == 0) { 549 u_quad_t res; 550 551 *p = 0; 552 res = (*ccfn)(buf, (char **)NULL, base); 553 if (flags & POINTER) 554 *va_arg(ap, void **) = 555 (void *)(long)res; 556 else if (flags & QUAD) 557 *va_arg(ap, quad_t *) = res; 558 else if (flags & LONG) 559 *va_arg(ap, long *) = res; 560 else if (flags & SHORT) 561 *va_arg(ap, short *) = res; 562 else 563 *va_arg(ap, int *) = res; 564 nassigned++; 565 } 566 nread += p - buf; 567 break; 568 569 #ifdef FLOATING_POINT 570 case CT_FLOAT: 571 /* scan a floating point number as if by strtod */ 572 #ifdef hardway 573 if (width == 0 || width > sizeof(buf) - 1) 574 width = sizeof(buf) - 1; 575 #else 576 /* size_t is unsigned, hence this optimisation */ 577 if (--width > sizeof(buf) - 2) 578 width = sizeof(buf) - 2; 579 width++; 580 #endif 581 flags |= SIGNOK | NDIGITS | DPTOK | EXPOK; 582 for (p = buf; width; width--) { 583 c = *fp->_p; 584 /* 585 * This code mimicks the integer conversion 586 * code, but is much simpler. 587 */ 588 switch (c) { 589 590 case '0': case '1': case '2': case '3': 591 case '4': case '5': case '6': case '7': 592 case '8': case '9': 593 flags &= ~(SIGNOK | NDIGITS); 594 goto fok; 595 596 case '+': case '-': 597 if (flags & SIGNOK) { 598 flags &= ~SIGNOK; 599 goto fok; 600 } 601 break; 602 case '.': 603 if (flags & DPTOK) { 604 flags &= ~(SIGNOK | DPTOK); 605 goto fok; 606 } 607 break; 608 case 'e': case 'E': 609 /* no exponent without some digits */ 610 if ((flags&(NDIGITS|EXPOK)) == EXPOK) { 611 flags = 612 (flags & ~(EXPOK|DPTOK)) | 613 SIGNOK | NDIGITS; 614 goto fok; 615 } 616 break; 617 } 618 break; 619 fok: 620 *p++ = c; 621 if (--fp->_r > 0) 622 fp->_p++; 623 else if (__srefill(fp)) 624 break; /* EOF */ 625 } 626 /* 627 * If no digits, might be missing exponent digits 628 * (just give back the exponent) or might be missing 629 * regular digits, but had sign and/or decimal point. 630 */ 631 if (flags & NDIGITS) { 632 if (flags & EXPOK) { 633 /* no digits at all */ 634 while (p > buf) 635 ungetc(*(u_char *)--p, fp); 636 goto match_failure; 637 } 638 /* just a bad exponent (e and maybe sign) */ 639 c = *(u_char *)--p; 640 if (c != 'e' && c != 'E') { 641 (void) ungetc(c, fp);/* sign */ 642 c = *(u_char *)--p; 643 } 644 (void) ungetc(c, fp); 645 } 646 if ((flags & SUPPRESS) == 0) { 647 double res; 648 649 *p = 0; 650 res = strtod(buf, (char **) NULL); 651 if (flags & LONGDBL) 652 *va_arg(ap, long double *) = res; 653 else if (flags & LONG) 654 *va_arg(ap, double *) = res; 655 else 656 *va_arg(ap, float *) = res; 657 nassigned++; 658 } 659 nread += p - buf; 660 break; 661 #endif /* FLOATING_POINT */ 662 } 663 } 664 input_failure: 665 return (nassigned ? nassigned : -1); 666 match_failure: 667 return (nassigned); 668 } 669 670 /* 671 * Fill in the given table from the scanset at the given format 672 * (just after `['). Return a pointer to the character past the 673 * closing `]'. The table has a 1 wherever characters should be 674 * considered part of the scanset. 675 */ 676 static u_char * 677 __sccl(tab, fmt) 678 register char *tab; 679 register u_char *fmt; 680 { 681 register int c, n, v; 682 683 /* first `clear' the whole table */ 684 c = *fmt++; /* first char hat => negated scanset */ 685 if (c == '^') { 686 v = 1; /* default => accept */ 687 c = *fmt++; /* get new first char */ 688 } else 689 v = 0; /* default => reject */ 690 /* should probably use memset here */ 691 for (n = 0; n < 256; n++) 692 tab[n] = v; 693 if (c == 0) 694 return (fmt - 1);/* format ended before closing ] */ 695 696 /* 697 * Now set the entries corresponding to the actual scanset 698 * to the opposite of the above. 699 * 700 * The first character may be ']' (or '-') without being special; 701 * the last character may be '-'. 702 */ 703 v = 1 - v; 704 for (;;) { 705 tab[c] = v; /* take character c */ 706 doswitch: 707 n = *fmt++; /* and examine the next */ 708 switch (n) { 709 710 case 0: /* format ended too soon */ 711 return (fmt - 1); 712 713 case '-': 714 /* 715 * A scanset of the form 716 * [01+-] 717 * is defined as `the digit 0, the digit 1, 718 * the character +, the character -', but 719 * the effect of a scanset such as 720 * [a-zA-Z0-9] 721 * is implementation defined. The V7 Unix 722 * scanf treats `a-z' as `the letters a through 723 * z', but treats `a-a' as `the letter a, the 724 * character -, and the letter a'. 725 * 726 * For compatibility, the `-' is not considerd 727 * to define a range if the character following 728 * it is either a close bracket (required by ANSI) 729 * or is not numerically greater than the character 730 * we just stored in the table (c). 731 */ 732 n = *fmt; 733 if (n == ']' || n < c) { 734 c = '-'; 735 break; /* resume the for(;;) */ 736 } 737 fmt++; 738 do { /* fill in the range */ 739 tab[++c] = v; 740 } while (c < n); 741 #if 1 /* XXX another disgusting compatibility hack */ 742 /* 743 * Alas, the V7 Unix scanf also treats formats 744 * such as [a-c-e] as `the letters a through e'. 745 * This too is permitted by the standard.... 746 */ 747 goto doswitch; 748 #else 749 c = *fmt++; 750 if (c == 0) 751 return (fmt - 1); 752 if (c == ']') 753 return (fmt); 754 #endif 755 break; 756 757 case ']': /* end of scanset */ 758 return (fmt); 759 760 default: /* just another character */ 761 c = n; 762 break; 763 } 764 } 765 /* NOTREACHED */ 766 } 767