1/*
2 * Copyright (c) 2004-2016 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*-
29 * Copyright (c) 1990, 1993
30 * The Regents of the University of California. All rights reserved.
31 *
32 * This code is derived from software contributed to Berkeley by
33 * Chris Torek.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. All advertising materials mentioning features or use of this software
44 * must display the following acknowledgement:
45 * This product includes software developed by the University of
46 * California, Berkeley and its contributors.
47 * 4. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 */
63
64#include <sys/cdefs.h>
65
66#if 0 /* XXX coming soon */
67#include <ctype.h>
68#else
69static inline int
70isspace(char c)
71{
72 return (c == ' ' || c == '\t' || c == '\n' || c == '\12');
73}
74#endif
75#include <stdarg.h>
76#include <string.h>
77#include <sys/param.h>
78#include <sys/systm.h>
79
80#define BUF 32 /* Maximum length of numeric string. */
81
82/*
83 * Flags used during conversion.
84 */
85#define LONG 0x01 /* l: long or double */
86#define SHORT 0x04 /* h: short */
87#define SUPPRESS 0x08 /* *: suppress assignment */
88#define POINTER 0x10 /* p: void * (as hex) */
89#define NOSKIP 0x20 /* [ or c: do not skip blanks */
90#define LONGLONG 0x400 /* ll: long long (+ deprecated q: quad) */
91#define SHORTSHORT 0x4000 /* hh: char */
92#define UNSIGNED 0x8000 /* %[oupxX] conversions */
93
94/*
95 * The following are used in numeric conversions only:
96 * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
97 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
98 */
99#define SIGNOK 0x40 /* +/- is (still) legal */
100#define NDIGITS 0x80 /* no digits detected */
101
102#define DPTOK 0x100 /* (float) decimal point is still legal */
103#define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */
104
105#define PFXOK 0x100 /* 0x prefix is (still) legal */
106#define NZDIGITS 0x200 /* no zero digits detected */
107
108/*
109 * Conversion types.
110 */
111#define CT_CHAR 0 /* %c conversion */
112#define CT_CCL 1 /* %[...] conversion */
113#define CT_STRING 2 /* %s conversion */
114#define CT_INT 3 /* %[dioupxX] conversion */
115
116static const u_char *__sccl(char *, const u_char *);
117
118int
119sscanf(const char *ibuf, const char *fmt, ...)
120{
121 va_list ap;
122 int ret;
123
124 va_start(ap, fmt);
125 ret = vsscanf(ibuf, fmt, ap);
126 va_end(ap);
127 return(ret);
128}
129
130int
131vsscanf(const char *inp, char const *fmt0, va_list ap)
132{
133 int inr;
134 const u_char *fmt = (const u_char *)fmt0;
135 int c; /* character from format, or conversion */
136 size_t width; /* field width, or 0 */
137 char *p; /* points into all kinds of strings */
138 int n; /* handy integer */
139 int flags; /* flags as defined above */
140 char *p0; /* saves original value of p when necessary */
141 int nassigned; /* number of fields assigned */
142 int nconversions; /* number of conversions */
143 int nread; /* number of characters consumed from fp */
144 int base; /* base argument to conversion function */
145 char ccltab[256]; /* character class table for %[...] */
146 char buf[BUF]; /* buffer for numeric conversions */
147
148 /* `basefix' is used to avoid `if' tests in the integer scanner */
149 static short basefix[17] =
150 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
151
152 inr = strlen(inp);
153
154 nassigned = 0;
155 nconversions = 0;
156 nread = 0;
157 base = 0; /* XXX just to keep gcc happy */
158 for (;;) {
159 c = *fmt++;
160 if (c == 0)
161 return (nassigned);
162 if (isspace(c)) {
163 while (inr > 0 && isspace(*inp)) {
164 nread++;
165 inr--;
166 inp++;
167 }
168 continue;
169 }
170 if (c != '%')
171 goto literal;
172 width = 0;
173 flags = 0;
174 /*
175 * switch on the format. continue if done;
176 * break once format type is derived.
177 */
178again: c = *fmt++;
179 switch (c) {
180 case '%':
181literal:
182 if (inr <= 0)
183 goto input_failure;
184 if (*inp != c)
185 goto match_failure;
186 inr--;
187 inp++;
188 nread++;
189 continue;
190
191 case '*':
192 flags |= SUPPRESS;
193 goto again;
194 case 'l':
195 if (flags & LONG) {
196 flags &= ~LONG;
197 flags |= LONGLONG;
198 } else
199 flags |= LONG;
200 goto again;
201 case 'q':
202 flags |= LONGLONG; /* not quite */
203 goto again;
204 case 'h':
205 if (flags & SHORT) {
206 flags &= ~SHORT;
207 flags |= SHORTSHORT;
208 } else
209 flags |= SHORT;
210 goto again;
211
212 case '0': case '1': case '2': case '3': case '4':
213 case '5': case '6': case '7': case '8': case '9':
214 width = width * 10 + c - '0';
215 goto again;
216
217 /*
218 * Conversions.
219 */
220 case 'd':
221 c = CT_INT;
222 base = 10;
223 break;
224
225 case 'i':
226 c = CT_INT;
227 base = 0;
228 break;
229
230 case 'o':
231 c = CT_INT;
232 flags |= UNSIGNED;
233 base = 8;
234 break;
235
236 case 'u':
237 c = CT_INT;
238 flags |= UNSIGNED;
239 base = 10;
240 break;
241
242 case 'X':
243 case 'x':
244 flags |= PFXOK; /* enable 0x prefixing */
245 c = CT_INT;
246 flags |= UNSIGNED;
247 base = 16;
248 break;
249
250 case 's':
251 c = CT_STRING;
252 break;
253
254 case '[':
255 fmt = __sccl(ccltab, fmt);
256 flags |= NOSKIP;
257 c = CT_CCL;
258 break;
259
260 case 'c':
261 flags |= NOSKIP;
262 c = CT_CHAR;
263 break;
264
265 case 'p': /* pointer format is like hex */
266 flags |= POINTER | PFXOK;
267 c = CT_INT;
268 flags |= UNSIGNED;
269 base = 16;
270 break;
271
272 case 'n':
273 nconversions++;
274 if (flags & SUPPRESS) /* ??? */
275 continue;
276 if (flags & SHORTSHORT)
277 *va_arg(ap, char *) = nread;
278 else if (flags & SHORT)
279 *va_arg(ap, short *) = nread;
280 else if (flags & LONG)
281 *va_arg(ap, long *) = nread;
282 else if (flags & LONGLONG)
283 *va_arg(ap, long long *) = nread;
284 else
285 *va_arg(ap, int *) = nread;
286 continue;
287 }
288
289 /*
290 * We have a conversion that requires input.
291 */
292 if (inr <= 0)
293 goto input_failure;
294
295 /*
296 * Consume leading white space, except for formats
297 * that suppress this.
298 */
299 if ((flags & NOSKIP) == 0) {
300 while (isspace(*inp)) {
301 nread++;
302 if (--inr > 0)
303 inp++;
304 else
305 goto input_failure;
306 }
307 /*
308 * Note that there is at least one character in
309 * the buffer, so conversions that do not set NOSKIP
310 * can no longer result in an input failure.
311 */
312 }
313
314 /*
315 * Do the conversion.
316 */
317 switch (c) {
318
319 case CT_CHAR:
320 /* scan arbitrary characters (sets NOSKIP) */
321 if (width == 0)
322 width = 1;
323 if (flags & SUPPRESS) {
324 size_t sum = 0;
325 for (;;) {
326 if ((n = inr) < (int)width) {
327 sum += n;
328 width -= n;
329 inp += n;
330 if (sum == 0)
331 goto input_failure;
332 break;
333 } else {
334 sum += width;
335 inr -= width;
336 inp += width;
337 break;
338 }
339 }
340 nread += sum;
341 } else {
342 bcopy(inp, va_arg(ap, char *), width);
343 inr -= width;
344 inp += width;
345 nread += width;
346 nassigned++;
347 }
348 nconversions++;
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[(unsigned char)*inp]) {
359 n++;
360 inr--;
361 inp++;
362 if (--width == 0)
363 break;
364 if (inr <= 0) {
365 if (n == 0)
366 goto input_failure;
367 break;
368 }
369 }
370 if (n == 0)
371 goto match_failure;
372 } else {
373 p0 = p = va_arg(ap, char *);
374 while (ccltab[(unsigned char)*inp]) {
375 inr--;
376 *p++ = *inp++;
377 if (--width == 0)
378 break;
379 if (inr <= 0) {
380 if (p == p0)
381 goto input_failure;
382 break;
383 }
384 }
385 n = p - p0;
386 if (n == 0)
387 goto match_failure;
388 *p = 0;
389 nassigned++;
390 }
391 nread += n;
392 nconversions++;
393 break;
394
395 case CT_STRING:
396 /* like CCL, but zero-length string OK, & no NOSKIP */
397 if (width == 0)
398 width = (size_t)~0;
399 if (flags & SUPPRESS) {
400 n = 0;
401 while (!isspace(*inp)) {
402 n++;
403 inr--;
404 inp++;
405 if (--width == 0)
406 break;
407 if (inr <= 0)
408 break;
409 }
410 nread += n;
411 } else {
412 p0 = p = va_arg(ap, char *);
413 while (!isspace(*inp)) {
414 inr--;
415 *p++ = *inp++;
416 if (--width == 0)
417 break;
418 if (inr <= 0)
419 break;
420 }
421 *p = 0;
422 nread += p - p0;
423 nassigned++;
424 }
425 nconversions++;
426 continue;
427
428 case CT_INT:
429 /* scan an integer as if by the conversion function */
430#ifdef hardway
431 if (width == 0 || width > sizeof(buf) - 1)
432 width = sizeof(buf) - 1;
433#else
434 /* size_t is unsigned, hence this optimisation */
435 if (--width > sizeof(buf) - 2)
436 width = sizeof(buf) - 2;
437 width++;
438#endif
439 flags |= SIGNOK | NDIGITS | NZDIGITS;
440 for (p = buf; width; width--) {
441 c = *inp;
442 /*
443 * Switch on the character; `goto ok'
444 * if we accept it as a part of number.
445 */
446 switch (c) {
447
448 /*
449 * The digit 0 is always legal, but is
450 * special. For %i conversions, if no
451 * digits (zero or nonzero) have been
452 * scanned (only signs), we will have
453 * base==0. In that case, we should set
454 * it to 8 and enable 0x prefixing.
455 * Also, if we have not scanned zero digits
456 * before this, do not turn off prefixing
457 * (someone else will turn it off if we
458 * have scanned any nonzero digits).
459 */
460 case '0':
461 if (base == 0) {
462 base = 8;
463 flags |= PFXOK;
464 }
465 if (flags & NZDIGITS)
466 flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
467 else
468 flags &= ~(SIGNOK|PFXOK|NDIGITS);
469 goto ok;
470
471 /* 1 through 7 always legal */
472 case '1': case '2': case '3':
473 case '4': case '5': case '6': case '7':
474 base = basefix[base];
475 flags &= ~(SIGNOK | PFXOK | NDIGITS);
476 goto ok;
477
478 /* digits 8 and 9 ok iff decimal or hex */
479 case '8': case '9':
480 base = basefix[base];
481 if (base <= 8)
482 break; /* not legal here */
483 flags &= ~(SIGNOK | PFXOK | NDIGITS);
484 goto ok;
485
486 /* letters ok iff hex */
487 case 'A': case 'B': case 'C':
488 case 'D': case 'E': case 'F':
489 case 'a': case 'b': case 'c':
490 case 'd': case 'e': case 'f':
491 /* no need to fix base here */
492 if (base <= 10)
493 break; /* not legal here */
494 flags &= ~(SIGNOK | PFXOK | NDIGITS);
495 goto ok;
496
497 /* sign ok only as first character */
498 case '+': case '-':
499 if (flags & SIGNOK) {
500 flags &= ~SIGNOK;
501 goto ok;
502 }
503 break;
504
505 /* x ok iff flag still set & 2nd char */
506 case 'x': case 'X':
507 if (flags & PFXOK && p == buf + 1) {
508 base = 16; /* if %i */
509 flags &= ~PFXOK;
510 goto ok;
511 }
512 break;
513 }
514
515 /*
516 * If we got here, c is not a legal character
517 * for a number. Stop accumulating digits.
518 */
519 break;
520 ok:
521 /*
522 * c is legal: store it and look at the next.
523 */
524 *p++ = c;
525 if (--inr > 0)
526 inp++;
527 else
528 break; /* end of input */
529 }
530 /*
531 * If we had only a sign, it is no good; push
532 * back the sign. If the number ends in `x',
533 * it was [sign] '0' 'x', so push back the x
534 * and treat it as [sign] '0'.
535 */
536 if (flags & NDIGITS) {
537 if (p > buf) {
538 inp--;
539 inr++;
540 }
541 goto match_failure;
542 }
543 c = ((u_char *)p)[-1];
544 if (c == 'x' || c == 'X') {
545 --p;
546 inp--;
547 inr++;
548 }
549 if ((flags & SUPPRESS) == 0) {
550 u_quad_t res;
551
552 *p = 0;
553 if ((flags & UNSIGNED) == 0)
554 res = strtoq(buf, (char **)NULL, base);
555 else
556 res = strtouq(buf, (char **)NULL, base);
557 if (flags & POINTER)
558 *va_arg(ap, void **) =
559 (void *)(uintptr_t)res;
560 else if (flags & SHORTSHORT)
561 *va_arg(ap, char *) = res;
562 else if (flags & SHORT)
563 *va_arg(ap, short *) = res;
564 else if (flags & LONG)
565 *va_arg(ap, long *) = res;
566 else if (flags & LONGLONG)
567 *va_arg(ap, long long *) = res;
568 else
569 *va_arg(ap, int *) = res;
570 nassigned++;
571 }
572 nread += p - buf;
573 nconversions++;
574 break;
575
576 }
577 }
578input_failure:
579 return (nconversions != 0 ? nassigned : -1);
580match_failure:
581 return (nassigned);
582}
583
584/*
585 * Fill in the given table from the scanset at the given format
586 * (just after `['). Return a pointer to the character past the
587 * closing `]'. The table has a 1 wherever characters should be
588 * considered part of the scanset.
589 */
590static const u_char *
591__sccl(char *tab, const u_char *fmt)
592{
593 int c, n, v;
594
595 /* first `clear' the whole table */
596 c = *fmt++; /* first char hat => negated scanset */
597 if (c == '^') {
598 v = 1; /* default => accept */
599 c = *fmt++; /* get new first char */
600 } else
601 v = 0; /* default => reject */
602
603 /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
604 (void) memset(tab, v, 256);
605
606 if (c == 0)
607 return (fmt - 1);/* format ended before closing ] */
608
609 /*
610 * Now set the entries corresponding to the actual scanset
611 * to the opposite of the above.
612 *
613 * The first character may be ']' (or '-') without being special;
614 * the last character may be '-'.
615 */
616 v = 1 - v;
617 for (;;) {
618 tab[c] = v; /* take character c */
619doswitch:
620 n = *fmt++; /* and examine the next */
621 switch (n) {
622
623 case 0: /* format ended too soon */
624 return (fmt - 1);
625
626 case '-':
627 /*
628 * A scanset of the form
629 * [01+-]
630 * is defined as `the digit 0, the digit 1,
631 * the character +, the character -', but
632 * the effect of a scanset such as
633 * [a-zA-Z0-9]
634 * is implementation defined. The V7 Unix
635 * scanf treats `a-z' as `the letters a through
636 * z', but treats `a-a' as `the letter a, the
637 * character -, and the letter a'.
638 *
639 * For compatibility, the `-' is not considerd
640 * to define a range if the character following
641 * it is either a close bracket (required by ANSI)
642 * or is not numerically greater than the character
643 * we just stored in the table (c).
644 */
645 n = *fmt;
646 if (n == ']' || n < c) {
647 c = '-';
648 break; /* resume the for(;;) */
649 }
650 fmt++;
651 /* fill in the range */
652 do {
653 tab[++c] = v;
654 } while (c < n);
655 c = n;
656 /*
657 * Alas, the V7 Unix scanf also treats formats
658 * such as [a-c-e] as `the letters a through e'.
659 * This too is permitted by the standard....
660 */
661 goto doswitch;
662
663 case ']': /* end of scanset */
664 return (fmt);
665
666 default: /* just another character */
667 c = n;
668 break;
669 }
670 }
671 /* NOTREACHED */
672}
673