xref: /freebsd/lib/libc/stdio/vfscanf.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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 static char sccsid[] = "@(#)vfscanf.c	8.1 (Berkeley) 6/4/93";
39 #endif /* LIBC_SCCS and not lint */
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include "namespace.h"
44 #include <ctype.h>
45 #include <inttypes.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <stddef.h>
49 #include <stdarg.h>
50 #include <string.h>
51 #include <wchar.h>
52 #include <wctype.h>
53 #include "un-namespace.h"
54 
55 #include "collate.h"
56 #include "libc_private.h"
57 #include "local.h"
58 
59 #define FLOATING_POINT
60 
61 #ifdef FLOATING_POINT
62 #include <locale.h>
63 #endif
64 
65 #define	BUF		513	/* Maximum length of numeric string. */
66 
67 /*
68  * Flags used during conversion.
69  */
70 #define	LONG		0x01	/* l: long or double */
71 #define	LONGDBL		0x02	/* L: long double */
72 #define	SHORT		0x04	/* h: short */
73 #define	SUPPRESS	0x08	/* *: suppress assignment */
74 #define	POINTER		0x10	/* p: void * (as hex) */
75 #define	NOSKIP		0x20	/* [ or c: do not skip blanks */
76 #define	LONGLONG	0x400	/* ll: long long (+ deprecated q: quad) */
77 #define	INTMAXT		0x800	/* j: intmax_t */
78 #define	PTRDIFFT	0x1000	/* t: ptrdiff_t */
79 #define	SIZET		0x2000	/* z: size_t */
80 #define	SHORTSHORT	0x4000	/* hh: char */
81 #define	UNSIGNED	0x8000	/* %[oupxX] conversions */
82 
83 /*
84  * The following are used in integral conversions only:
85  * SIGNOK, NDIGITS, PFXOK, and NZDIGITS
86  */
87 #define	SIGNOK		0x40	/* +/- is (still) legal */
88 #define	NDIGITS		0x80	/* no digits detected */
89 #define	PFXOK		0x100	/* 0x prefix is (still) legal */
90 #define	NZDIGITS	0x200	/* no zero digits detected */
91 
92 /*
93  * Conversion types.
94  */
95 #define	CT_CHAR		0	/* %c conversion */
96 #define	CT_CCL		1	/* %[...] conversion */
97 #define	CT_STRING	2	/* %s conversion */
98 #define	CT_INT		3	/* %[dioupxX] conversion */
99 #define	CT_FLOAT	4	/* %[efgEFG] conversion */
100 
101 static const u_char *__sccl(char *, const u_char *);
102 static int parsefloat(FILE *, char *, char *);
103 
104 int __scanfdebug = 0;
105 
106 __weak_reference(__vfscanf, vfscanf);
107 
108 /*
109  * __vfscanf - MT-safe version
110  */
111 int
112 __vfscanf(FILE *fp, char const *fmt0, va_list ap)
113 {
114 	int ret;
115 
116 	FLOCKFILE(fp);
117 	ret = __svfscanf(fp, fmt0, ap);
118 	FUNLOCKFILE(fp);
119 	return (ret);
120 }
121 
122 /*
123  * __svfscanf - non-MT-safe version of __vfscanf
124  */
125 int
126 __svfscanf(FILE *fp, const char *fmt0, va_list ap)
127 {
128 	const u_char *fmt = (const u_char *)fmt0;
129 	int c;			/* character from format, or conversion */
130 	size_t width;		/* field width, or 0 */
131 	char *p;		/* points into all kinds of strings */
132 	int n;			/* handy integer */
133 	int flags;		/* flags as defined above */
134 	char *p0;		/* saves original value of p when necessary */
135 	int nassigned;		/* number of fields assigned */
136 	int nconversions;	/* number of conversions */
137 	int nread;		/* number of characters consumed from fp */
138 	int base;		/* base argument to conversion function */
139 	char ccltab[256];	/* character class table for %[...] */
140 	char buf[BUF];		/* buffer for numeric and mb conversions */
141 	wchar_t *wcp;		/* handy wide character pointer */
142 	wchar_t *wcp0;		/* saves original value of wcp */
143 	mbstate_t mbs;		/* multibyte conversion state */
144 	size_t nconv;		/* length of multibyte sequence converted */
145 
146 	/* `basefix' is used to avoid `if' tests in the integer scanner */
147 	static short basefix[17] =
148 		{ 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
149 
150 	ORIENT(fp, -1);
151 
152 	nassigned = 0;
153 	nconversions = 0;
154 	nread = 0;
155 	for (;;) {
156 		c = *fmt++;
157 		if (c == 0)
158 			return (nassigned);
159 		if (isspace(c)) {
160 			while ((fp->_r > 0 || __srefill(fp) == 0) && isspace(*fp->_p))
161 				nread++, fp->_r--, fp->_p++;
162 			continue;
163 		}
164 		if (c != '%')
165 			goto literal;
166 		width = 0;
167 		flags = 0;
168 		/*
169 		 * switch on the format.  continue if done;
170 		 * break once format type is derived.
171 		 */
172 again:		c = *fmt++;
173 		switch (c) {
174 		case '%':
175 literal:
176 			if (fp->_r <= 0 && __srefill(fp))
177 				goto input_failure;
178 			if (*fp->_p != c)
179 				goto match_failure;
180 			fp->_r--, fp->_p++;
181 			nread++;
182 			continue;
183 
184 		case '*':
185 			flags |= SUPPRESS;
186 			goto again;
187 		case 'j':
188 			flags |= INTMAXT;
189 			goto again;
190 		case 'l':
191 			if (flags & LONG) {
192 				flags &= ~LONG;
193 				flags |= LONGLONG;
194 			} else
195 				flags |= LONG;
196 			goto again;
197 		case 'q':
198 			flags |= LONGLONG;	/* not quite */
199 			goto again;
200 		case 't':
201 			flags |= PTRDIFFT;
202 			goto again;
203 		case 'z':
204 			flags |= SIZET;
205 			goto again;
206 		case 'L':
207 			flags |= LONGDBL;
208 			goto again;
209 		case 'h':
210 			if (flags & SHORT) {
211 				flags &= ~SHORT;
212 				flags |= SHORTSHORT;
213 			} else
214 				flags |= SHORT;
215 			goto again;
216 
217 		case '0': case '1': case '2': case '3': case '4':
218 		case '5': case '6': case '7': case '8': case '9':
219 			width = width * 10 + c - '0';
220 			goto again;
221 
222 		/*
223 		 * Conversions.
224 		 */
225 		case 'd':
226 			c = CT_INT;
227 			base = 10;
228 			break;
229 
230 		case 'i':
231 			c = CT_INT;
232 			base = 0;
233 			break;
234 
235 		case 'o':
236 			c = CT_INT;
237 			flags |= UNSIGNED;
238 			base = 8;
239 			break;
240 
241 		case 'u':
242 			c = CT_INT;
243 			flags |= UNSIGNED;
244 			base = 10;
245 			break;
246 
247 		case 'X':
248 		case 'x':
249 			flags |= PFXOK;	/* enable 0x prefixing */
250 			c = CT_INT;
251 			flags |= UNSIGNED;
252 			base = 16;
253 			break;
254 
255 #ifdef FLOATING_POINT
256 		case 'A': case 'E': case 'F': case 'G':
257 		case 'a': case 'e': case 'f': case 'g':
258 			c = CT_FLOAT;
259 			break;
260 #endif
261 
262 		case 'S':
263 			flags |= LONG;
264 			/* FALLTHROUGH */
265 		case 's':
266 			c = CT_STRING;
267 			break;
268 
269 		case '[':
270 			fmt = __sccl(ccltab, fmt);
271 			flags |= NOSKIP;
272 			c = CT_CCL;
273 			break;
274 
275 		case 'C':
276 			flags |= LONG;
277 			/* FALLTHROUGH */
278 		case 'c':
279 			flags |= NOSKIP;
280 			c = CT_CHAR;
281 			break;
282 
283 		case 'p':	/* pointer format is like hex */
284 			flags |= POINTER | PFXOK;
285 			c = CT_INT;		/* assumes sizeof(uintmax_t) */
286 			flags |= UNSIGNED;	/*      >= sizeof(uintptr_t) */
287 			base = 16;
288 			break;
289 
290 		case 'n':
291 			nconversions++;
292 			if (flags & SUPPRESS)	/* ??? */
293 				continue;
294 			if (flags & SHORTSHORT)
295 				*va_arg(ap, char *) = nread;
296 			else if (flags & SHORT)
297 				*va_arg(ap, short *) = nread;
298 			else if (flags & LONG)
299 				*va_arg(ap, long *) = nread;
300 			else if (flags & LONGLONG)
301 				*va_arg(ap, long long *) = nread;
302 			else if (flags & INTMAXT)
303 				*va_arg(ap, intmax_t *) = nread;
304 			else if (flags & SIZET)
305 				*va_arg(ap, size_t *) = nread;
306 			else if (flags & PTRDIFFT)
307 				*va_arg(ap, ptrdiff_t *) = nread;
308 			else
309 				*va_arg(ap, int *) = nread;
310 			continue;
311 
312 		default:
313 			goto match_failure;
314 
315 		/*
316 		 * Disgusting backwards compatibility hack.	XXX
317 		 */
318 		case '\0':	/* compat */
319 			return (EOF);
320 		}
321 
322 		/*
323 		 * We have a conversion that requires input.
324 		 */
325 		if (fp->_r <= 0 && __srefill(fp))
326 			goto input_failure;
327 
328 		/*
329 		 * Consume leading white space, except for formats
330 		 * that suppress this.
331 		 */
332 		if ((flags & NOSKIP) == 0) {
333 			while (isspace(*fp->_p)) {
334 				nread++;
335 				if (--fp->_r > 0)
336 					fp->_p++;
337 				else if (__srefill(fp))
338 					goto input_failure;
339 			}
340 			/*
341 			 * Note that there is at least one character in
342 			 * the buffer, so conversions that do not set NOSKIP
343 			 * ca no longer result in an input failure.
344 			 */
345 		}
346 
347 		/*
348 		 * Do the conversion.
349 		 */
350 		switch (c) {
351 
352 		case CT_CHAR:
353 			/* scan arbitrary characters (sets NOSKIP) */
354 			if (width == 0)
355 				width = 1;
356 			if (flags & LONG) {
357 				if ((flags & SUPPRESS) == 0)
358 					wcp = va_arg(ap, wchar_t *);
359 				else
360 					wcp = NULL;
361 				n = 0;
362 				while (width != 0) {
363 					if (n == MB_CUR_MAX) {
364 						fp->_flags |= __SERR;
365 						goto input_failure;
366 					}
367 					buf[n++] = *fp->_p;
368 					fp->_p++;
369 					fp->_r--;
370 					memset(&mbs, 0, sizeof(mbs));
371 					nconv = mbrtowc(wcp, buf, n, &mbs);
372 					if (nconv == (size_t)-1) {
373 						fp->_flags |= __SERR;
374 						goto input_failure;
375 					}
376 					if (nconv == 0 && !(flags & SUPPRESS))
377 						*wcp = L'\0';
378 					if (nconv != (size_t)-2) {
379 						nread += n;
380 						width--;
381 						if (!(flags & SUPPRESS))
382 							wcp++;
383 						n = 0;
384 					}
385 					if (fp->_r <= 0 && __srefill(fp)) {
386 						if (n != 0) {
387 							fp->_flags |= __SERR;
388 							goto input_failure;
389 						}
390 						break;
391 					}
392 				}
393 				if (!(flags & SUPPRESS))
394 					nassigned++;
395 			} else if (flags & SUPPRESS) {
396 				size_t sum = 0;
397 				for (;;) {
398 					if ((n = fp->_r) < width) {
399 						sum += n;
400 						width -= n;
401 						fp->_p += n;
402 						if (__srefill(fp)) {
403 							if (sum == 0)
404 							    goto input_failure;
405 							break;
406 						}
407 					} else {
408 						sum += width;
409 						fp->_r -= width;
410 						fp->_p += width;
411 						break;
412 					}
413 				}
414 				nread += sum;
415 			} else {
416 				size_t r = fread((void *)va_arg(ap, char *), 1,
417 				    width, fp);
418 
419 				if (r == 0)
420 					goto input_failure;
421 				nread += r;
422 				nassigned++;
423 			}
424 			nconversions++;
425 			break;
426 
427 		case CT_CCL:
428 			/* scan a (nonempty) character class (sets NOSKIP) */
429 			if (width == 0)
430 				width = (size_t)~0;	/* `infinity' */
431 			/* take only those things in the class */
432 			if (flags & LONG) {
433 				wchar_t twc;
434 				int nchars;
435 
436 				if ((flags & SUPPRESS) == 0)
437 					wcp = wcp0 = va_arg(ap, wchar_t *);
438 				else
439 					wcp = wcp0 = &twc;
440 				n = 0;
441 				nchars = 0;
442 				while (width != 0) {
443 					if (n == MB_CUR_MAX) {
444 						fp->_flags |= __SERR;
445 						goto input_failure;
446 					}
447 					buf[n++] = *fp->_p;
448 					fp->_p++;
449 					fp->_r--;
450 					memset(&mbs, 0, sizeof(mbs));
451 					nconv = mbrtowc(wcp, buf, n, &mbs);
452 					if (nconv == (size_t)-1) {
453 						fp->_flags |= __SERR;
454 						goto input_failure;
455 					}
456 					if (nconv == 0)
457 						*wcp = L'\0';
458 					if (nconv != (size_t)-2) {
459 						if (wctob(*wcp) != EOF &&
460 						    !ccltab[wctob(*wcp)]) {
461 							while (n != 0) {
462 								n--;
463 								__ungetc(buf[n],
464 								    fp);
465 							}
466 							break;
467 						}
468 						nread += n;
469 						width--;
470 						if (!(flags & SUPPRESS))
471 							wcp++;
472 						nchars++;
473 						n = 0;
474 					}
475 					if (fp->_r <= 0 && __srefill(fp)) {
476 						if (n != 0) {
477 							fp->_flags |= __SERR;
478 							goto input_failure;
479 						}
480 						break;
481 					}
482 				}
483 				if (n != 0) {
484 					fp->_flags |= __SERR;
485 					goto input_failure;
486 				}
487 				n = nchars;
488 				if (n == 0)
489 					goto match_failure;
490 				if (!(flags & SUPPRESS)) {
491 					*wcp = L'\0';
492 					nassigned++;
493 				}
494 			} else if (flags & SUPPRESS) {
495 				n = 0;
496 				while (ccltab[*fp->_p]) {
497 					n++, fp->_r--, fp->_p++;
498 					if (--width == 0)
499 						break;
500 					if (fp->_r <= 0 && __srefill(fp)) {
501 						if (n == 0)
502 							goto input_failure;
503 						break;
504 					}
505 				}
506 				if (n == 0)
507 					goto match_failure;
508 			} else {
509 				p0 = p = va_arg(ap, char *);
510 				while (ccltab[*fp->_p]) {
511 					fp->_r--;
512 					*p++ = *fp->_p++;
513 					if (--width == 0)
514 						break;
515 					if (fp->_r <= 0 && __srefill(fp)) {
516 						if (p == p0)
517 							goto input_failure;
518 						break;
519 					}
520 				}
521 				n = p - p0;
522 				if (n == 0)
523 					goto match_failure;
524 				*p = 0;
525 				nassigned++;
526 			}
527 			nread += n;
528 			nconversions++;
529 			break;
530 
531 		case CT_STRING:
532 			/* like CCL, but zero-length string OK, & no NOSKIP */
533 			if (width == 0)
534 				width = (size_t)~0;
535 			if (flags & LONG) {
536 				wchar_t twc;
537 
538 				if ((flags & SUPPRESS) == 0)
539 					wcp = va_arg(ap, wchar_t *);
540 				else
541 					wcp = &twc;
542 				n = 0;
543 				while (!isspace(*fp->_p) && width != 0) {
544 					if (n == MB_CUR_MAX) {
545 						fp->_flags |= __SERR;
546 						goto input_failure;
547 					}
548 					buf[n++] = *fp->_p;
549 					fp->_p++;
550 					fp->_r--;
551 					memset(&mbs, 0, sizeof(mbs));
552 					nconv = mbrtowc(wcp, buf, n, &mbs);
553 					if (nconv == (size_t)-1) {
554 						fp->_flags |= __SERR;
555 						goto input_failure;
556 					}
557 					if (nconv == 0)
558 						*wcp = L'\0';
559 					if (nconv != (size_t)-2) {
560 						if (iswspace(*wcp)) {
561 							while (n != 0) {
562 								n--;
563 								__ungetc(buf[n],
564 								    fp);
565 							}
566 							break;
567 						}
568 						nread += n;
569 						width--;
570 						if (!(flags & SUPPRESS))
571 							wcp++;
572 						n = 0;
573 					}
574 					if (fp->_r <= 0 && __srefill(fp)) {
575 						if (n != 0) {
576 							fp->_flags |= __SERR;
577 							goto input_failure;
578 						}
579 						break;
580 					}
581 				}
582 				if (!(flags & SUPPRESS)) {
583 					*wcp = L'\0';
584 					nassigned++;
585 				}
586 			} else if (flags & SUPPRESS) {
587 				n = 0;
588 				while (!isspace(*fp->_p)) {
589 					n++, fp->_r--, fp->_p++;
590 					if (--width == 0)
591 						break;
592 					if (fp->_r <= 0 && __srefill(fp))
593 						break;
594 				}
595 				nread += n;
596 			} else {
597 				p0 = p = va_arg(ap, char *);
598 				while (!isspace(*fp->_p)) {
599 					fp->_r--;
600 					*p++ = *fp->_p++;
601 					if (--width == 0)
602 						break;
603 					if (fp->_r <= 0 && __srefill(fp))
604 						break;
605 				}
606 				*p = 0;
607 				nread += p - p0;
608 				nassigned++;
609 			}
610 			nconversions++;
611 			continue;
612 
613 		case CT_INT:
614 			/* scan an integer as if by the conversion function */
615 #ifdef hardway
616 			if (width == 0 || width > sizeof(buf) - 1)
617 				width = sizeof(buf) - 1;
618 #else
619 			/* size_t is unsigned, hence this optimisation */
620 			if (--width > sizeof(buf) - 2)
621 				width = sizeof(buf) - 2;
622 			width++;
623 #endif
624 			flags |= SIGNOK | NDIGITS | NZDIGITS;
625 			for (p = buf; width; width--) {
626 				c = *fp->_p;
627 				/*
628 				 * Switch on the character; `goto ok'
629 				 * if we accept it as a part of number.
630 				 */
631 				switch (c) {
632 
633 				/*
634 				 * The digit 0 is always legal, but is
635 				 * special.  For %i conversions, if no
636 				 * digits (zero or nonzero) have been
637 				 * scanned (only signs), we will have
638 				 * base==0.  In that case, we should set
639 				 * it to 8 and enable 0x prefixing.
640 				 * Also, if we have not scanned zero digits
641 				 * before this, do not turn off prefixing
642 				 * (someone else will turn it off if we
643 				 * have scanned any nonzero digits).
644 				 */
645 				case '0':
646 					if (base == 0) {
647 						base = 8;
648 						flags |= PFXOK;
649 					}
650 					if (flags & NZDIGITS)
651 					    flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
652 					else
653 					    flags &= ~(SIGNOK|PFXOK|NDIGITS);
654 					goto ok;
655 
656 				/* 1 through 7 always legal */
657 				case '1': case '2': case '3':
658 				case '4': case '5': case '6': case '7':
659 					base = basefix[base];
660 					flags &= ~(SIGNOK | PFXOK | NDIGITS);
661 					goto ok;
662 
663 				/* digits 8 and 9 ok iff decimal or hex */
664 				case '8': case '9':
665 					base = basefix[base];
666 					if (base <= 8)
667 						break;	/* not legal here */
668 					flags &= ~(SIGNOK | PFXOK | NDIGITS);
669 					goto ok;
670 
671 				/* letters ok iff hex */
672 				case 'A': case 'B': case 'C':
673 				case 'D': case 'E': case 'F':
674 				case 'a': case 'b': case 'c':
675 				case 'd': case 'e': case 'f':
676 					/* no need to fix base here */
677 					if (base <= 10)
678 						break;	/* not legal here */
679 					flags &= ~(SIGNOK | PFXOK | NDIGITS);
680 					goto ok;
681 
682 				/* sign ok only as first character */
683 				case '+': case '-':
684 					if (flags & SIGNOK) {
685 						flags &= ~SIGNOK;
686 						goto ok;
687 					}
688 					break;
689 
690 				/* x ok iff flag still set & 2nd char */
691 				case 'x': case 'X':
692 					if (flags & PFXOK && p == buf + 1) {
693 						base = 16;	/* if %i */
694 						flags &= ~PFXOK;
695 						goto ok;
696 					}
697 					break;
698 				}
699 
700 				/*
701 				 * If we got here, c is not a legal character
702 				 * for a number.  Stop accumulating digits.
703 				 */
704 				break;
705 		ok:
706 				/*
707 				 * c is legal: store it and look at the next.
708 				 */
709 				*p++ = c;
710 				if (--fp->_r > 0)
711 					fp->_p++;
712 				else if (__srefill(fp))
713 					break;		/* EOF */
714 			}
715 			/*
716 			 * If we had only a sign, it is no good; push
717 			 * back the sign.  If the number ends in `x',
718 			 * it was [sign] '0' 'x', so push back the x
719 			 * and treat it as [sign] '0'.
720 			 */
721 			if (flags & NDIGITS) {
722 				if (p > buf)
723 					(void) __ungetc(*(u_char *)--p, fp);
724 				goto match_failure;
725 			}
726 			c = ((u_char *)p)[-1];
727 			if (c == 'x' || c == 'X') {
728 				--p;
729 				(void) __ungetc(c, fp);
730 			}
731 			if ((flags & SUPPRESS) == 0) {
732 				uintmax_t res;
733 
734 				*p = 0;
735 				if ((flags & UNSIGNED) == 0)
736 				    res = strtoimax(buf, (char **)NULL, base);
737 				else
738 				    res = strtoumax(buf, (char **)NULL, base);
739 				if (flags & POINTER)
740 					*va_arg(ap, void **) =
741 							(void *)(uintptr_t)res;
742 				else if (flags & SHORTSHORT)
743 					*va_arg(ap, char *) = res;
744 				else if (flags & SHORT)
745 					*va_arg(ap, short *) = res;
746 				else if (flags & LONG)
747 					*va_arg(ap, long *) = res;
748 				else if (flags & LONGLONG)
749 					*va_arg(ap, long long *) = res;
750 				else if (flags & INTMAXT)
751 					*va_arg(ap, intmax_t *) = res;
752 				else if (flags & PTRDIFFT)
753 					*va_arg(ap, ptrdiff_t *) = res;
754 				else if (flags & SIZET)
755 					*va_arg(ap, size_t *) = res;
756 				else
757 					*va_arg(ap, int *) = res;
758 				nassigned++;
759 			}
760 			nread += p - buf;
761 			nconversions++;
762 			break;
763 
764 #ifdef FLOATING_POINT
765 		case CT_FLOAT:
766 			/* scan a floating point number as if by strtod */
767 			if (width == 0 || width > sizeof(buf) - 1)
768 				width = sizeof(buf) - 1;
769 			if ((width = parsefloat(fp, buf, buf + width)) == 0)
770 				goto match_failure;
771 			if ((flags & SUPPRESS) == 0) {
772 				if (flags & LONGDBL) {
773 					long double res = strtold(buf, &p);
774 					*va_arg(ap, long double *) = res;
775 				} else if (flags & LONG) {
776 					double res = strtod(buf, &p);
777 					*va_arg(ap, double *) = res;
778 				} else {
779 					float res = strtof(buf, &p);
780 					*va_arg(ap, float *) = res;
781 				}
782 				if (__scanfdebug && p - buf != width)
783 					abort();
784 				nassigned++;
785 			}
786 			nread += width;
787 			nconversions++;
788 			break;
789 #endif /* FLOATING_POINT */
790 		}
791 	}
792 input_failure:
793 	return (nconversions != 0 ? nassigned : EOF);
794 match_failure:
795 	return (nassigned);
796 }
797 
798 /*
799  * Fill in the given table from the scanset at the given format
800  * (just after `[').  Return a pointer to the character past the
801  * closing `]'.  The table has a 1 wherever characters should be
802  * considered part of the scanset.
803  */
804 static const u_char *
805 __sccl(tab, fmt)
806 	char *tab;
807 	const u_char *fmt;
808 {
809 	int c, n, v, i;
810 
811 	/* first `clear' the whole table */
812 	c = *fmt++;		/* first char hat => negated scanset */
813 	if (c == '^') {
814 		v = 1;		/* default => accept */
815 		c = *fmt++;	/* get new first char */
816 	} else
817 		v = 0;		/* default => reject */
818 
819 	/* XXX: Will not work if sizeof(tab*) > sizeof(char) */
820 	(void) memset(tab, v, 256);
821 
822 	if (c == 0)
823 		return (fmt - 1);/* format ended before closing ] */
824 
825 	/*
826 	 * Now set the entries corresponding to the actual scanset
827 	 * to the opposite of the above.
828 	 *
829 	 * The first character may be ']' (or '-') without being special;
830 	 * the last character may be '-'.
831 	 */
832 	v = 1 - v;
833 	for (;;) {
834 		tab[c] = v;		/* take character c */
835 doswitch:
836 		n = *fmt++;		/* and examine the next */
837 		switch (n) {
838 
839 		case 0:			/* format ended too soon */
840 			return (fmt - 1);
841 
842 		case '-':
843 			/*
844 			 * A scanset of the form
845 			 *	[01+-]
846 			 * is defined as `the digit 0, the digit 1,
847 			 * the character +, the character -', but
848 			 * the effect of a scanset such as
849 			 *	[a-zA-Z0-9]
850 			 * is implementation defined.  The V7 Unix
851 			 * scanf treats `a-z' as `the letters a through
852 			 * z', but treats `a-a' as `the letter a, the
853 			 * character -, and the letter a'.
854 			 *
855 			 * For compatibility, the `-' is not considerd
856 			 * to define a range if the character following
857 			 * it is either a close bracket (required by ANSI)
858 			 * or is not numerically greater than the character
859 			 * we just stored in the table (c).
860 			 */
861 			n = *fmt;
862 			if (n == ']'
863 			    || (__collate_load_error ? n < c :
864 				__collate_range_cmp (n, c) < 0
865 			       )
866 			   ) {
867 				c = '-';
868 				break;	/* resume the for(;;) */
869 			}
870 			fmt++;
871 			/* fill in the range */
872 			if (__collate_load_error) {
873 				do {
874 					tab[++c] = v;
875 				} while (c < n);
876 			} else {
877 				for (i = 0; i < 256; i ++)
878 					if (   __collate_range_cmp (c, i) < 0
879 					    && __collate_range_cmp (i, n) <= 0
880 					   )
881 						tab[i] = v;
882 			}
883 #if 1	/* XXX another disgusting compatibility hack */
884 			c = n;
885 			/*
886 			 * Alas, the V7 Unix scanf also treats formats
887 			 * such as [a-c-e] as `the letters a through e'.
888 			 * This too is permitted by the standard....
889 			 */
890 			goto doswitch;
891 #else
892 			c = *fmt++;
893 			if (c == 0)
894 				return (fmt - 1);
895 			if (c == ']')
896 				return (fmt);
897 #endif
898 			break;
899 
900 		case ']':		/* end of scanset */
901 			return (fmt);
902 
903 		default:		/* just another character */
904 			c = n;
905 			break;
906 		}
907 	}
908 	/* NOTREACHED */
909 }
910 
911 #ifdef FLOATING_POINT
912 static int
913 parsefloat(FILE *fp, char *buf, char *end)
914 {
915 	char *commit, *p;
916 	int infnanpos = 0;
917 	enum {
918 		S_START, S_GOTSIGN, S_INF, S_NAN, S_MAYBEHEX,
919 		S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
920 	} state = S_START;
921 	unsigned char c;
922 	char decpt = *localeconv()->decimal_point;
923 	_Bool gotmantdig = 0, ishex = 0;
924 
925 	/*
926 	 * We set commit = p whenever the string we have read so far
927 	 * constitutes a valid representation of a floating point
928 	 * number by itself.  At some point, the parse will complete
929 	 * or fail, and we will ungetc() back to the last commit point.
930 	 * To ensure that the file offset gets updated properly, it is
931 	 * always necessary to read at least one character that doesn't
932 	 * match; thus, we can't short-circuit "infinity" or "nan(...)".
933 	 */
934 	commit = buf - 1;
935 	for (p = buf; p < end; ) {
936 		c = *fp->_p;
937 reswitch:
938 		switch (state) {
939 		case S_START:
940 			state = S_GOTSIGN;
941 			if (c == '-' || c == '+')
942 				break;
943 			else
944 				goto reswitch;
945 		case S_GOTSIGN:
946 			switch (c) {
947 			case '0':
948 				state = S_MAYBEHEX;
949 				commit = p;
950 				break;
951 			case 'I':
952 			case 'i':
953 				state = S_INF;
954 				break;
955 			case 'N':
956 			case 'n':
957 				state = S_NAN;
958 				break;
959 			default:
960 				state = S_DIGITS;
961 				goto reswitch;
962 			}
963 			break;
964 		case S_INF:
965 			if (infnanpos > 6 ||
966 			    (c != "nfinity"[infnanpos] &&
967 			     c != "NFINITY"[infnanpos]))
968 				goto parsedone;
969 			if (infnanpos == 1 || infnanpos == 6)
970 				commit = p;	/* inf or infinity */
971 			infnanpos++;
972 			break;
973 		case S_NAN:
974 			switch (infnanpos) {
975 			case -1:	/* XXX kludge to deal with nan(...) */
976 				goto parsedone;
977 			case 0:
978 				if (c != 'A' && c != 'a')
979 					goto parsedone;
980 				break;
981 			case 1:
982 				if (c != 'N' && c != 'n')
983 					goto parsedone;
984 				else
985 					commit = p;
986 				break;
987 			case 2:
988 				if (c != '(')
989 					goto parsedone;
990 				break;
991 			default:
992 				if (c == ')') {
993 					commit = p;
994 					infnanpos = -2;
995 				} else if (!isalnum(c) && c != '_')
996 					goto parsedone;
997 				break;
998 			}
999 			infnanpos++;
1000 			break;
1001 		case S_MAYBEHEX:
1002 			state = S_DIGITS;
1003 			if (c == 'X' || c == 'x') {
1004 				ishex = 1;
1005 				break;
1006 			} else {	/* we saw a '0', but no 'x' */
1007 				gotmantdig = 1;
1008 				goto reswitch;
1009 			}
1010 		case S_DIGITS:
1011 			if (ishex && isxdigit(c) || isdigit(c))
1012 				gotmantdig = 1;
1013 			else {
1014 				state = S_FRAC;
1015 				if (c != decpt)
1016 					goto reswitch;
1017 			}
1018 			if (gotmantdig)
1019 				commit = p;
1020 			break;
1021 		case S_FRAC:
1022 			if ((c == 'E' || c == 'e') && !ishex ||
1023 			    (c == 'P' || c == 'p') && ishex) {
1024 				if (!gotmantdig)
1025 					goto parsedone;
1026 				else
1027 					state = S_EXP;
1028 			} else if (ishex && isxdigit(c) || isdigit(c)) {
1029 				commit = p;
1030 				gotmantdig = 1;
1031 			} else
1032 				goto parsedone;
1033 			break;
1034 		case S_EXP:
1035 			state = S_EXPDIGITS;
1036 			if (c == '-' || c == '+')
1037 				break;
1038 			else
1039 				goto reswitch;
1040 		case S_EXPDIGITS:
1041 			if (isdigit(c))
1042 				commit = p;
1043 			else
1044 				goto parsedone;
1045 			break;
1046 		default:
1047 			abort();
1048 		}
1049 		*p++ = c;
1050 		if (--fp->_r > 0)
1051 			fp->_p++;
1052 		else if (__srefill(fp))
1053 			break;	/* EOF */
1054 	}
1055 
1056 parsedone:
1057 	while (commit < --p)
1058 		__ungetc(*(u_char *)p, fp);
1059 	*++commit = '\0';
1060 	return (commit - buf);
1061 }
1062 #endif
1063