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 * 4. 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 * From: Id: vfscanf.c,v 1.13 1998/09/25 12:20:27 obrien Exp
33 * From: static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93";
34 * From: static char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93";
35 */
36
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/ctype.h>
43 #include <sys/limits.h>
44 #include <sys/stddef.h>
45
46 /*
47 * Note that stdarg.h and the ANSI style va_start macro is used for both
48 * ANSI and traditional C compilers.
49 */
50 #include <machine/stdarg.h>
51
52 #define BUF 32 /* Maximum length of numeric string. */
53
54 /*
55 * Flags used during conversion.
56 */
57 #define LONG 0x01 /* l: long or double */
58 #define SHORT 0x04 /* h: short */
59 #define SUPPRESS 0x08 /* suppress assignment */
60 #define POINTER 0x10 /* weird %p pointer (`fake hex') */
61 #define NOSKIP 0x20 /* do not skip blanks */
62 #define QUAD 0x400
63 #define INTMAXT 0x800 /* j: intmax_t */
64 #define PTRDIFFT 0x1000 /* t: ptrdiff_t */
65 #define SIZET 0x2000 /* z: size_t */
66 #define SHORTSHORT 0x4000 /** hh: char */
67
68 /*
69 * The following are used in numeric conversions only:
70 * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
71 * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
72 */
73 #define SIGNOK 0x40 /* +/- is (still) legal */
74 #define NDIGITS 0x80 /* no digits detected */
75
76 #define DPTOK 0x100 /* (float) decimal point is still legal */
77 #define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */
78
79 #define PFXOK 0x100 /* 0x prefix is (still) legal */
80 #define NZDIGITS 0x200 /* no zero digits detected */
81
82 /*
83 * Conversion types.
84 */
85 #define CT_CHAR 0 /* %c conversion */
86 #define CT_CCL 1 /* %[...] conversion */
87 #define CT_STRING 2 /* %s conversion */
88 #define CT_INT 3 /* integer, i.e., strtoq or strtouq */
89 typedef u_quad_t (*ccfntype)(const char *, char **, int);
90
91 static const u_char *__sccl(char *, const u_char *);
92
93 int
sscanf(const char * ibuf,const char * fmt,...)94 sscanf(const char *ibuf, const char *fmt, ...)
95 {
96 va_list ap;
97 int ret;
98
99 va_start(ap, fmt);
100 ret = vsscanf(ibuf, fmt, ap);
101 va_end(ap);
102 return(ret);
103 }
104
105 int
vsscanf(const char * inp,char const * fmt0,va_list ap)106 vsscanf(const char *inp, char const *fmt0, va_list ap)
107 {
108 int inr;
109 const u_char *fmt = (const u_char *)fmt0;
110 int c; /* character from format, or conversion */
111 size_t width; /* field width, or 0 */
112 char *p; /* points into all kinds of strings */
113 int n; /* handy integer */
114 int flags; /* flags as defined above */
115 char *p0; /* saves original value of p when necessary */
116 int nassigned; /* number of fields assigned */
117 int nconversions; /* number of conversions */
118 int nread; /* number of characters consumed from fp */
119 int base; /* base argument to strtoq/strtouq */
120 ccfntype ccfn; /* conversion function (strtoq/strtouq) */
121 char ccltab[256]; /* character class table for %[...] */
122 char buf[BUF]; /* buffer for numeric conversions */
123
124 /* `basefix' is used to avoid `if' tests in the integer scanner */
125 static short basefix[17] =
126 { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
127
128 inr = strlen(inp);
129
130 nassigned = 0;
131 nconversions = 0;
132 nread = 0;
133 base = 0; /* XXX just to keep gcc happy */
134 ccfn = NULL; /* XXX just to keep gcc happy */
135 for (;;) {
136 c = *fmt++;
137 if (c == 0)
138 return (nassigned);
139 if (isspace(c)) {
140 while (inr > 0 && isspace(*inp))
141 nread++, inr--, inp++;
142 continue;
143 }
144 if (c != '%')
145 goto literal;
146 width = 0;
147 flags = 0;
148 /*
149 * switch on the format. continue if done;
150 * break once format type is derived.
151 */
152 again: c = *fmt++;
153 switch (c) {
154 case '%':
155 literal:
156 if (inr <= 0)
157 goto input_failure;
158 if (*inp != c)
159 goto match_failure;
160 inr--, inp++;
161 nread++;
162 continue;
163
164 case '*':
165 flags |= SUPPRESS;
166 goto again;
167 case 'j':
168 flags |= INTMAXT;
169 goto again;
170 case 'l':
171 if (flags & LONG){
172 flags &= ~LONG;
173 flags |= QUAD;
174 } else {
175 flags |= LONG;
176 }
177 goto again;
178 case 'q':
179 flags |= QUAD;
180 goto again;
181 case 't':
182 flags |= PTRDIFFT;
183 goto again;
184 case 'z':
185 flags |= SIZET;
186 goto again;
187 case 'h':
188 if (flags & SHORT){
189 flags &= ~SHORT;
190 flags |= SHORTSHORT;
191 } else {
192 flags |= SHORT;
193 }
194 goto again;
195
196 case '0': case '1': case '2': case '3': case '4':
197 case '5': case '6': case '7': case '8': case '9':
198 width = width * 10 + c - '0';
199 goto again;
200
201 /*
202 * Conversions.
203 *
204 */
205 case 'd':
206 c = CT_INT;
207 ccfn = (ccfntype)strtoq;
208 base = 10;
209 break;
210
211 case 'i':
212 c = CT_INT;
213 ccfn = (ccfntype)strtoq;
214 base = 0;
215 break;
216
217 case 'o':
218 c = CT_INT;
219 ccfn = strtouq;
220 base = 8;
221 break;
222
223 case 'u':
224 c = CT_INT;
225 ccfn = strtouq;
226 base = 10;
227 break;
228
229 case 'x':
230 flags |= PFXOK; /* enable 0x prefixing */
231 c = CT_INT;
232 ccfn = strtouq;
233 base = 16;
234 break;
235
236 case 's':
237 c = CT_STRING;
238 break;
239
240 case '[':
241 fmt = __sccl(ccltab, fmt);
242 flags |= NOSKIP;
243 c = CT_CCL;
244 break;
245
246 case 'c':
247 flags |= NOSKIP;
248 c = CT_CHAR;
249 break;
250
251 case 'p': /* pointer format is like hex */
252 flags |= POINTER | PFXOK;
253 c = CT_INT;
254 ccfn = strtouq;
255 base = 16;
256 break;
257
258 case 'n':
259 nconversions++;
260 if (flags & SUPPRESS) /* ??? */
261 continue;
262 if (flags & SHORTSHORT)
263 *va_arg(ap, char *) = nread;
264 else if (flags & SHORT)
265 *va_arg(ap, short *) = nread;
266 else if (flags & LONG)
267 *va_arg(ap, long *) = nread;
268 else if (flags & QUAD)
269 *va_arg(ap, quad_t *) = nread;
270 else if (flags & INTMAXT)
271 *va_arg(ap, intmax_t *) = nread;
272 else if (flags & SIZET)
273 *va_arg(ap, size_t *) = nread;
274 else if (flags & PTRDIFFT)
275 *va_arg(ap, ptrdiff_t *) = nread;
276 else
277 *va_arg(ap, int *) = nread;
278 continue;
279 }
280
281 /*
282 * We have a conversion that requires input.
283 */
284 if (inr <= 0)
285 goto input_failure;
286
287 /*
288 * Consume leading white space, except for formats
289 * that suppress this.
290 */
291 if ((flags & NOSKIP) == 0) {
292 while (isspace(*inp)) {
293 nread++;
294 if (--inr > 0)
295 inp++;
296 else
297 goto input_failure;
298 }
299 /*
300 * Note that there is at least one character in
301 * the buffer, so conversions that do not set NOSKIP
302 * can no longer result in an input failure.
303 */
304 }
305
306 /*
307 * Do the conversion.
308 */
309 switch (c) {
310
311 case CT_CHAR:
312 /* scan arbitrary characters (sets NOSKIP) */
313 if (width == 0)
314 width = 1;
315 if (flags & SUPPRESS) {
316 size_t sum = 0;
317 for (;;) {
318 if ((n = inr) < width) {
319 sum += n;
320 width -= n;
321 inp += n;
322 if (sum == 0)
323 goto input_failure;
324 break;
325 } else {
326 sum += width;
327 inr -= width;
328 inp += width;
329 break;
330 }
331 }
332 nread += sum;
333 } else {
334 bcopy(inp, va_arg(ap, char *), width);
335 inr -= width;
336 inp += width;
337 nread += width;
338 nassigned++;
339 }
340 nconversions++;
341 break;
342
343 case CT_CCL:
344 /* scan a (nonempty) character class (sets NOSKIP) */
345 if (width == 0)
346 width = (size_t)~0; /* `infinity' */
347 /* take only those things in the class */
348 if (flags & SUPPRESS) {
349 n = 0;
350 while (ccltab[(unsigned char)*inp]) {
351 n++, inr--, inp++;
352 if (--width == 0)
353 break;
354 if (inr <= 0) {
355 if (n == 0)
356 goto input_failure;
357 break;
358 }
359 }
360 if (n == 0)
361 goto match_failure;
362 } else {
363 p0 = p = va_arg(ap, char *);
364 while (ccltab[(unsigned char)*inp]) {
365 inr--;
366 *p++ = *inp++;
367 if (--width == 0)
368 break;
369 if (inr <= 0) {
370 if (p == p0)
371 goto input_failure;
372 break;
373 }
374 }
375 n = p - p0;
376 if (n == 0)
377 goto match_failure;
378 *p = 0;
379 nassigned++;
380 }
381 nread += n;
382 nconversions++;
383 break;
384
385 case CT_STRING:
386 /* like CCL, but zero-length string OK, & no NOSKIP */
387 if (width == 0)
388 width = (size_t)~0;
389 if (flags & SUPPRESS) {
390 n = 0;
391 while (!isspace(*inp)) {
392 n++, inr--, inp++;
393 if (--width == 0)
394 break;
395 if (inr <= 0)
396 break;
397 }
398 nread += n;
399 } else {
400 p0 = p = va_arg(ap, char *);
401 while (!isspace(*inp)) {
402 inr--;
403 *p++ = *inp++;
404 if (--width == 0)
405 break;
406 if (inr <= 0)
407 break;
408 }
409 *p = 0;
410 nread += p - p0;
411 nassigned++;
412 }
413 nconversions++;
414 continue;
415
416 case CT_INT:
417 /* scan an integer as if by strtoq/strtouq */
418 #ifdef hardway
419 if (width == 0 || width > sizeof(buf) - 1)
420 width = sizeof(buf) - 1;
421 #else
422 /* size_t is unsigned, hence this optimisation */
423 if (--width > sizeof(buf) - 2)
424 width = sizeof(buf) - 2;
425 width++;
426 #endif
427 flags |= SIGNOK | NDIGITS | NZDIGITS;
428 for (p = buf; width; width--) {
429 c = *inp;
430 /*
431 * Switch on the character; `goto ok'
432 * if we accept it as a part of number.
433 */
434 switch (c) {
435
436 /*
437 * The digit 0 is always legal, but is
438 * special. For %i conversions, if no
439 * digits (zero or nonzero) have been
440 * scanned (only signs), we will have
441 * base==0. In that case, we should set
442 * it to 8 and enable 0x prefixing.
443 * Also, if we have not scanned zero digits
444 * before this, do not turn off prefixing
445 * (someone else will turn it off if we
446 * have scanned any nonzero digits).
447 */
448 case '0':
449 if (base == 0) {
450 base = 8;
451 flags |= PFXOK;
452 }
453 if (flags & NZDIGITS)
454 flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
455 else
456 flags &= ~(SIGNOK|PFXOK|NDIGITS);
457 goto ok;
458
459 /* 1 through 7 always legal */
460 case '1': case '2': case '3':
461 case '4': case '5': case '6': case '7':
462 base = basefix[base];
463 flags &= ~(SIGNOK | PFXOK | NDIGITS);
464 goto ok;
465
466 /* digits 8 and 9 ok iff decimal or hex */
467 case '8': case '9':
468 base = basefix[base];
469 if (base <= 8)
470 break; /* not legal here */
471 flags &= ~(SIGNOK | PFXOK | NDIGITS);
472 goto ok;
473
474 /* letters ok iff hex */
475 case 'A': case 'B': case 'C':
476 case 'D': case 'E': case 'F':
477 case 'a': case 'b': case 'c':
478 case 'd': case 'e': case 'f':
479 /* no need to fix base here */
480 if (base <= 10)
481 break; /* not legal here */
482 flags &= ~(SIGNOK | PFXOK | NDIGITS);
483 goto ok;
484
485 /* sign ok only as first character */
486 case '+': case '-':
487 if (flags & SIGNOK) {
488 flags &= ~SIGNOK;
489 goto ok;
490 }
491 break;
492
493 /* x ok iff flag still set & 2nd char */
494 case 'x': case 'X':
495 if (flags & PFXOK && p == buf + 1) {
496 base = 16; /* if %i */
497 flags &= ~PFXOK;
498 goto ok;
499 }
500 break;
501 }
502
503 /*
504 * If we got here, c is not a legal character
505 * for a number. Stop accumulating digits.
506 */
507 break;
508 ok:
509 /*
510 * c is legal: store it and look at the next.
511 */
512 *p++ = c;
513 if (--inr > 0)
514 inp++;
515 else
516 break; /* end of input */
517 }
518 /*
519 * If we had only a sign, it is no good; push
520 * back the sign. If the number ends in `x',
521 * it was [sign] '0' 'x', so push back the x
522 * and treat it as [sign] '0'.
523 */
524 if (flags & NDIGITS) {
525 if (p > buf) {
526 inp--;
527 inr++;
528 }
529 goto match_failure;
530 }
531 c = ((u_char *)p)[-1];
532 if (c == 'x' || c == 'X') {
533 --p;
534 inp--;
535 inr++;
536 }
537 if ((flags & SUPPRESS) == 0) {
538 u_quad_t res;
539
540 *p = 0;
541 res = (*ccfn)(buf, (char **)NULL, base);
542 if (flags & POINTER)
543 *va_arg(ap, void **) =
544 (void *)(uintptr_t)res;
545 else if (flags & SHORTSHORT)
546 *va_arg(ap, char *) = 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 if (flags & QUAD)
552 *va_arg(ap, quad_t *) = res;
553 else if (flags & INTMAXT)
554 *va_arg(ap, intmax_t *) = res;
555 else if (flags & PTRDIFFT)
556 *va_arg(ap, ptrdiff_t *) = res;
557 else if (flags & SIZET)
558 *va_arg(ap, size_t *) = res;
559 else
560 *va_arg(ap, int *) = res;
561 nassigned++;
562 }
563 nread += p - buf;
564 nconversions++;
565 break;
566
567 }
568 }
569 input_failure:
570 return (nconversions != 0 ? nassigned : -1);
571 match_failure:
572 return (nassigned);
573 }
574
575 /*
576 * Fill in the given table from the scanset at the given format
577 * (just after `['). Return a pointer to the character past the
578 * closing `]'. The table has a 1 wherever characters should be
579 * considered part of the scanset.
580 */
581 static const u_char *
__sccl(char * tab,const u_char * fmt)582 __sccl(char *tab, const u_char *fmt)
583 {
584 int c, n, v;
585
586 /* first `clear' the whole table */
587 c = *fmt++; /* first char hat => negated scanset */
588 if (c == '^') {
589 v = 1; /* default => accept */
590 c = *fmt++; /* get new first char */
591 } else
592 v = 0; /* default => reject */
593
594 /* XXX: Will not work if sizeof(tab*) > sizeof(char) */
595 for (n = 0; n < 256; n++)
596 tab[n] = v; /* memset(tab, v, 256) */
597
598 if (c == 0)
599 return (fmt - 1);/* format ended before closing ] */
600
601 /*
602 * Now set the entries corresponding to the actual scanset
603 * to the opposite of the above.
604 *
605 * The first character may be ']' (or '-') without being special;
606 * the last character may be '-'.
607 */
608 v = 1 - v;
609 for (;;) {
610 tab[c] = v; /* take character c */
611 doswitch:
612 n = *fmt++; /* and examine the next */
613 switch (n) {
614
615 case 0: /* format ended too soon */
616 return (fmt - 1);
617
618 case '-':
619 /*
620 * A scanset of the form
621 * [01+-]
622 * is defined as `the digit 0, the digit 1,
623 * the character +, the character -', but
624 * the effect of a scanset such as
625 * [a-zA-Z0-9]
626 * is implementation defined. The V7 Unix
627 * scanf treats `a-z' as `the letters a through
628 * z', but treats `a-a' as `the letter a, the
629 * character -, and the letter a'.
630 *
631 * For compatibility, the `-' is not considered
632 * to define a range if the character following
633 * it is either a close bracket (required by ANSI)
634 * or is not numerically greater than the character
635 * we just stored in the table (c).
636 */
637 n = *fmt;
638 if (n == ']' || n < c) {
639 c = '-';
640 break; /* resume the for(;;) */
641 }
642 fmt++;
643 /* fill in the range */
644 do {
645 tab[++c] = v;
646 } while (c < n);
647 c = n;
648 /*
649 * Alas, the V7 Unix scanf also treats formats
650 * such as [a-c-e] as `the letters a through e'.
651 * This too is permitted by the standard....
652 */
653 goto doswitch;
654 break;
655
656 case ']': /* end of scanset */
657 return (fmt);
658
659 default: /* just another character */
660 c = n;
661 break;
662 }
663 }
664 /* NOTREACHED */
665 }
666
667