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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD: src/sys/kern/subr_scanf.c,v 1.13 1999/11/24 01:03:01 archie Exp $ 33 * $DragonFly: src/sys/kern/subr_scanf.c,v 1.4 2006/12/13 21:58:50 dillon Exp $ 34 * From: Id: vfscanf.c,v 1.13 1998/09/25 12:20:27 obrien Exp 35 * From: static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93"; 36 * From: static char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93"; 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/ctype.h> 42 #include <machine/limits.h> 43 44 /* 45 * Note that stdarg.h and the ANSI style va_start macro is used for both 46 * ANSI and traditional C compilers. 47 */ 48 #include <machine/stdarg.h> 49 50 #define BUF 32 /* Maximum length of numeric string. */ 51 52 /* 53 * Flags used during conversion. 54 */ 55 #define LONG 0x01 /* l: long or double */ 56 #define SHORT 0x04 /* h: short */ 57 #define SUPPRESS 0x08 /* suppress assignment */ 58 #define POINTER 0x10 /* weird %p pointer (`fake hex') */ 59 #define NOSKIP 0x20 /* do not skip blanks */ 60 #define QUAD 0x400 61 #define SHORTSHORT 0x4000 /* hh: char */ 62 63 /* 64 * The following are used in numeric conversions only: 65 * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point; 66 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral. 67 */ 68 #define SIGNOK 0x40 /* +/- is (still) legal */ 69 #define NDIGITS 0x80 /* no digits detected */ 70 71 #define DPTOK 0x100 /* (float) decimal point is still legal */ 72 #define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */ 73 74 #define PFXOK 0x100 /* 0x prefix is (still) legal */ 75 #define NZDIGITS 0x200 /* no zero digits detected */ 76 77 /* 78 * Conversion types. 79 */ 80 #define CT_CHAR 0 /* %c conversion */ 81 #define CT_CCL 1 /* %[...] conversion */ 82 #define CT_STRING 2 /* %s conversion */ 83 #define CT_INT 3 /* integer, i.e., strtoq or strtouq */ 84 typedef u_quad_t (*ccfntype)(const char *, char **, int); 85 86 static const u_char *__sccl(char *, const u_char *); 87 88 int 89 ksscanf(const char *ibuf, const char *fmt, ...) 90 { 91 __va_list ap; 92 int ret; 93 94 __va_start(ap, fmt); 95 ret = kvsscanf(ibuf, fmt, ap); 96 __va_end(ap); 97 return(ret); 98 } 99 100 int 101 kvsscanf(const char *inp, char const *fmt0, __va_list ap) 102 { 103 int inr; 104 const u_char *fmt = (const u_char *)fmt0; 105 int c; /* character from format, or conversion */ 106 size_t width; /* field width, or 0 */ 107 char *p; /* points into all kinds of strings */ 108 int n; /* handy integer */ 109 int flags; /* flags as defined above */ 110 char *p0; /* saves original value of p when necessary */ 111 int nassigned; /* number of fields assigned */ 112 int nconversions; /* number of conversions */ 113 int nread; /* number of characters consumed from fp */ 114 int base; /* base argument to strtoq/strtouq */ 115 ccfntype ccfn; /* conversion function (strtoq/strtouq) */ 116 char ccltab[256]; /* character class table for %[...] */ 117 char buf[BUF]; /* buffer for numeric conversions */ 118 119 /* `basefix' is used to avoid `if' tests in the integer scanner */ 120 static short basefix[17] = 121 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 122 123 inr = strlen(inp); 124 125 nassigned = 0; 126 nconversions = 0; 127 nread = 0; 128 base = 0; /* XXX just to keep gcc happy */ 129 ccfn = NULL; /* XXX just to keep gcc happy */ 130 for (;;) { 131 c = *fmt++; 132 if (c == 0) 133 return (nassigned); 134 if (isspace(c)) { 135 while (inr > 0 && isspace(*inp)) 136 nread++, inr--, inp++; 137 continue; 138 } 139 if (c != '%') 140 goto literal; 141 width = 0; 142 flags = 0; 143 /* 144 * switch on the format. continue if done; 145 * break once format type is derived. 146 */ 147 again: c = *fmt++; 148 switch (c) { 149 case '%': 150 literal: 151 if (inr <= 0) 152 goto input_failure; 153 if (*inp != c) 154 goto match_failure; 155 inr--, inp++; 156 nread++; 157 continue; 158 159 case '*': 160 flags |= SUPPRESS; 161 goto again; 162 case 'l': 163 flags |= LONG; 164 goto again; 165 case 'q': 166 flags |= QUAD; 167 goto again; 168 case 'h': 169 if (flags & SHORT) { 170 flags &= ~SHORT; 171 flags |= SHORTSHORT; 172 } else 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 * 184 */ 185 case 'd': 186 c = CT_INT; 187 ccfn = (ccfntype)strtoq; 188 base = 10; 189 break; 190 191 case 'i': 192 c = CT_INT; 193 ccfn = (ccfntype)strtoq; 194 base = 0; 195 break; 196 197 case 'o': 198 c = CT_INT; 199 ccfn = strtouq; 200 base = 8; 201 break; 202 203 case 'u': 204 c = CT_INT; 205 ccfn = strtouq; 206 base = 10; 207 break; 208 209 case 'x': 210 flags |= PFXOK; /* enable 0x prefixing */ 211 c = CT_INT; 212 ccfn = strtouq; 213 base = 16; 214 break; 215 216 case 's': 217 c = CT_STRING; 218 break; 219 220 case '[': 221 fmt = __sccl(ccltab, fmt); 222 flags |= NOSKIP; 223 c = CT_CCL; 224 break; 225 226 case 'c': 227 flags |= NOSKIP; 228 c = CT_CHAR; 229 break; 230 231 case 'p': /* pointer format is like hex */ 232 flags |= POINTER | PFXOK; 233 c = CT_INT; 234 ccfn = strtouq; 235 base = 16; 236 break; 237 238 case 'n': 239 nconversions++; 240 if (flags & SUPPRESS) /* ??? */ 241 continue; 242 if (flags & SHORTSHORT) 243 *__va_arg(ap, char *) = nread; 244 else if (flags & SHORT) 245 *__va_arg(ap, short *) = nread; 246 else if (flags & LONG) 247 *__va_arg(ap, long *) = nread; 248 else if (flags & QUAD) 249 *__va_arg(ap, quad_t *) = nread; 250 else 251 *__va_arg(ap, int *) = nread; 252 continue; 253 } 254 255 /* 256 * We have a conversion that requires input. 257 */ 258 if (inr <= 0) 259 goto input_failure; 260 261 /* 262 * Consume leading white space, except for formats 263 * that suppress this. 264 */ 265 if ((flags & NOSKIP) == 0) { 266 while (isspace(*inp)) { 267 nread++; 268 if (--inr > 0) 269 inp++; 270 else 271 goto input_failure; 272 } 273 /* 274 * Note that there is at least one character in 275 * the buffer, so conversions that do not set NOSKIP 276 * can no longer result in an input failure. 277 */ 278 } 279 280 /* 281 * Do the conversion. 282 */ 283 switch (c) { 284 285 case CT_CHAR: 286 /* scan arbitrary characters (sets NOSKIP) */ 287 if (width == 0) 288 width = 1; 289 if (flags & SUPPRESS) { 290 size_t sum = 0; 291 for (;;) { 292 if ((n = inr) < width) { 293 sum += n; 294 width -= n; 295 inp += n; 296 if (sum == 0) 297 goto input_failure; 298 break; 299 } else { 300 sum += width; 301 inr -= width; 302 inp += width; 303 break; 304 } 305 } 306 nread += sum; 307 } else { 308 bcopy(inp, __va_arg(ap, char *), width); 309 inr -= width; 310 inp += width; 311 nread += width; 312 nassigned++; 313 } 314 nconversions++; 315 break; 316 317 case CT_CCL: 318 /* scan a (nonempty) character class (sets NOSKIP) */ 319 if (width == 0) 320 width = (size_t)~0; /* `infinity' */ 321 /* take only those things in the class */ 322 if (flags & SUPPRESS) { 323 n = 0; 324 while (ccltab[(unsigned char)*inp]) { 325 n++, inr--, inp++; 326 if (--width == 0) 327 break; 328 if (inr <= 0) { 329 if (n == 0) 330 goto input_failure; 331 break; 332 } 333 } 334 if (n == 0) 335 goto match_failure; 336 } else { 337 p0 = p = __va_arg(ap, char *); 338 while (ccltab[(unsigned char)*inp]) { 339 inr--; 340 *p++ = *inp++; 341 if (--width == 0) 342 break; 343 if (inr <= 0) { 344 if (p == p0) 345 goto input_failure; 346 break; 347 } 348 } 349 n = p - p0; 350 if (n == 0) 351 goto match_failure; 352 *p = 0; 353 nassigned++; 354 } 355 nread += n; 356 nconversions++; 357 break; 358 359 case CT_STRING: 360 /* like CCL, but zero-length string OK, & no NOSKIP */ 361 if (width == 0) 362 width = (size_t)~0; 363 if (flags & SUPPRESS) { 364 n = 0; 365 while (!isspace(*inp)) { 366 n++, inr--, inp++; 367 if (--width == 0) 368 break; 369 if (inr <= 0) 370 break; 371 } 372 nread += n; 373 } else { 374 p0 = p = __va_arg(ap, char *); 375 while (!isspace(*inp)) { 376 inr--; 377 *p++ = *inp++; 378 if (--width == 0) 379 break; 380 if (inr <= 0) 381 break; 382 } 383 *p = 0; 384 nread += p - p0; 385 nassigned++; 386 } 387 nconversions++; 388 continue; 389 390 case CT_INT: 391 /* scan an integer as if by strtoq/strtouq */ 392 #ifdef hardway 393 if (width == 0 || width > sizeof(buf) - 1) 394 width = sizeof(buf) - 1; 395 #else 396 /* size_t is unsigned, hence this optimisation */ 397 if (--width > sizeof(buf) - 2) 398 width = sizeof(buf) - 2; 399 width++; 400 #endif 401 flags |= SIGNOK | NDIGITS | NZDIGITS; 402 for (p = buf; width; width--) { 403 c = *inp; 404 /* 405 * Switch on the character; `goto ok' 406 * if we accept it as a part of number. 407 */ 408 switch (c) { 409 410 /* 411 * The digit 0 is always legal, but is 412 * special. For %i conversions, if no 413 * digits (zero or nonzero) have been 414 * scanned (only signs), we will have 415 * base==0. In that case, we should set 416 * it to 8 and enable 0x prefixing. 417 * Also, if we have not scanned zero digits 418 * before this, do not turn off prefixing 419 * (someone else will turn it off if we 420 * have scanned any nonzero digits). 421 */ 422 case '0': 423 if (base == 0) { 424 base = 8; 425 flags |= PFXOK; 426 } 427 if (flags & NZDIGITS) 428 flags &= ~(SIGNOK|NZDIGITS|NDIGITS); 429 else 430 flags &= ~(SIGNOK|PFXOK|NDIGITS); 431 goto ok; 432 433 /* 1 through 7 always legal */ 434 case '1': case '2': case '3': 435 case '4': case '5': case '6': case '7': 436 base = basefix[base]; 437 flags &= ~(SIGNOK | PFXOK | NDIGITS); 438 goto ok; 439 440 /* digits 8 and 9 ok iff decimal or hex */ 441 case '8': case '9': 442 base = basefix[base]; 443 if (base <= 8) 444 break; /* not legal here */ 445 flags &= ~(SIGNOK | PFXOK | NDIGITS); 446 goto ok; 447 448 /* letters ok iff hex */ 449 case 'A': case 'B': case 'C': 450 case 'D': case 'E': case 'F': 451 case 'a': case 'b': case 'c': 452 case 'd': case 'e': case 'f': 453 /* no need to fix base here */ 454 if (base <= 10) 455 break; /* not legal here */ 456 flags &= ~(SIGNOK | PFXOK | NDIGITS); 457 goto ok; 458 459 /* sign ok only as first character */ 460 case '+': case '-': 461 if (flags & SIGNOK) { 462 flags &= ~SIGNOK; 463 goto ok; 464 } 465 break; 466 467 /* x ok iff flag still set & 2nd char */ 468 case 'x': case 'X': 469 if (flags & PFXOK && p == buf + 1) { 470 base = 16; /* if %i */ 471 flags &= ~PFXOK; 472 goto ok; 473 } 474 break; 475 } 476 477 /* 478 * If we got here, c is not a legal character 479 * for a number. Stop accumulating digits. 480 */ 481 break; 482 ok: 483 /* 484 * c is legal: store it and look at the next. 485 */ 486 *p++ = c; 487 if (--inr > 0) 488 inp++; 489 else 490 break; /* end of input */ 491 } 492 /* 493 * If we had only a sign, it is no good; push 494 * back the sign. If the number ends in `x', 495 * it was [sign] '0' 'x', so push back the x 496 * and treat it as [sign] '0'. 497 */ 498 if (flags & NDIGITS) { 499 if (p > buf) { 500 inp--; 501 inr++; 502 } 503 goto match_failure; 504 } 505 c = ((u_char *)p)[-1]; 506 if (c == 'x' || c == 'X') { 507 --p; 508 inp--; 509 inr++; 510 } 511 if ((flags & SUPPRESS) == 0) { 512 u_quad_t res; 513 514 *p = 0; 515 res = (*ccfn)(buf, NULL, base); 516 if (flags & POINTER) 517 *__va_arg(ap, void **) = 518 (void *)(uintptr_t)res; 519 else if (flags & SHORTSHORT) 520 *__va_arg(ap, char *) = res; 521 else if (flags & SHORT) 522 *__va_arg(ap, short *) = res; 523 else if (flags & LONG) 524 *__va_arg(ap, long *) = res; 525 else if (flags & QUAD) 526 *__va_arg(ap, quad_t *) = res; 527 else 528 *__va_arg(ap, int *) = res; 529 nassigned++; 530 } 531 nread += p - buf; 532 nconversions++; 533 break; 534 535 } 536 } 537 input_failure: 538 return (nconversions != 0 ? nassigned : -1); 539 match_failure: 540 return (nassigned); 541 } 542 543 /* 544 * Fill in the given table from the scanset at the given format 545 * (just after `['). Return a pointer to the character past the 546 * closing `]'. The table has a 1 wherever characters should be 547 * considered part of the scanset. 548 */ 549 static const u_char * 550 __sccl(char *tab, const u_char *fmt) 551 { 552 int c, n, v; 553 554 /* first `clear' the whole table */ 555 c = *fmt++; /* first char hat => negated scanset */ 556 if (c == '^') { 557 v = 1; /* default => accept */ 558 c = *fmt++; /* get new first char */ 559 } else 560 v = 0; /* default => reject */ 561 562 /* XXX: Will not work if sizeof(tab*) > sizeof(char) */ 563 for (n = 0; n < 256; n++) 564 tab[n] = v; /* memset(tab, v, 256) */ 565 566 if (c == 0) 567 return (fmt - 1);/* format ended before closing ] */ 568 569 /* 570 * Now set the entries corresponding to the actual scanset 571 * to the opposite of the above. 572 * 573 * The first character may be ']' (or '-') without being special; 574 * the last character may be '-'. 575 */ 576 v = 1 - v; 577 for (;;) { 578 tab[c] = v; /* take character c */ 579 doswitch: 580 n = *fmt++; /* and examine the next */ 581 switch (n) { 582 583 case 0: /* format ended too soon */ 584 return (fmt - 1); 585 586 case '-': 587 /* 588 * A scanset of the form 589 * [01+-] 590 * is defined as `the digit 0, the digit 1, 591 * the character +, the character -', but 592 * the effect of a scanset such as 593 * [a-zA-Z0-9] 594 * is implementation defined. The V7 Unix 595 * scanf treats `a-z' as `the letters a through 596 * z', but treats `a-a' as `the letter a, the 597 * character -, and the letter a'. 598 * 599 * For compatibility, the `-' is not considerd 600 * to define a range if the character following 601 * it is either a close bracket (required by ANSI) 602 * or is not numerically greater than the character 603 * we just stored in the table (c). 604 */ 605 n = *fmt; 606 if (n == ']' || n < c) { 607 c = '-'; 608 break; /* resume the for(;;) */ 609 } 610 fmt++; 611 /* fill in the range */ 612 do { 613 tab[++c] = v; 614 } while (c < n); 615 c = n; 616 /* 617 * Alas, the V7 Unix scanf also treats formats 618 * such as [a-c-e] as `the letters a through e'. 619 * This too is permitted by the standard.... 620 */ 621 goto doswitch; 622 break; 623 624 case ']': /* end of scanset */ 625 return (fmt); 626 627 default: /* just another character */ 628 c = n; 629 break; 630 } 631 } 632 /* NOTREACHED */ 633 } 634 635