xref: /freebsd/lib/libc/stdio/vfwscanf.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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  * Copyright (c) 2011 The FreeBSD Foundation
11  * All rights reserved.
12  * Portions of this software were developed by David Chisnall
13  * under sponsorship from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #if 0
41 #if defined(LIBC_SCCS) && !defined(lint)
42 static char sccsid[] = "@(#)vfscanf.c	8.1 (Berkeley) 6/4/93";
43 #endif /* LIBC_SCCS and not lint */
44 #endif
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include "namespace.h"
49 #include <ctype.h>
50 #include <inttypes.h>
51 #include <limits.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <stddef.h>
55 #include <stdarg.h>
56 #include <string.h>
57 #include <wchar.h>
58 #include <wctype.h>
59 #include "un-namespace.h"
60 
61 #include "libc_private.h"
62 #include "local.h"
63 #include "xlocale_private.h"
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 #define	HAVESIGN	0x10000	/* sign detected */
92 
93 /*
94  * Conversion types.
95  */
96 #define	CT_CHAR		0	/* %c conversion */
97 #define	CT_CCL		1	/* %[...] conversion */
98 #define	CT_STRING	2	/* %s conversion */
99 #define	CT_INT		3	/* %[dioupxX] conversion */
100 #define	CT_FLOAT	4	/* %[efgEFG] conversion */
101 
102 #ifndef NO_FLOATING_POINT
103 static int parsefloat(FILE *, wchar_t *, wchar_t *, locale_t);
104 #endif
105 
106 struct ccl {
107 	const wchar_t *start;	/* character class start */
108 	const wchar_t *end;	/* character class end */
109 	int compl;		/* ccl is complemented? */
110 };
111 
112 static __inline int
113 inccl(const struct ccl *ccl, wint_t wi)
114 {
115 
116 	if (ccl->compl) {
117 		return (wmemchr(ccl->start, wi, ccl->end - ccl->start)
118 		    == NULL);
119 	} else {
120 		return (wmemchr(ccl->start, wi, ccl->end - ccl->start) != NULL);
121 	}
122 }
123 
124 /*
125  * Conversion functions are passed a pointer to this object instead of
126  * a real parameter to indicate that the assignment-suppression (*)
127  * flag was specified.  We could use a NULL pointer to indicate this,
128  * but that would mask bugs in applications that call scanf() with a
129  * NULL pointer.
130  */
131 static const int suppress;
132 #define	SUPPRESS_PTR	((void *)&suppress)
133 
134 static const mbstate_t initial_mbs;
135 
136 /*
137  * The following conversion functions return the number of characters consumed,
138  * or -1 on input failure.  Character class conversion returns 0 on match
139  * failure.
140  */
141 
142 static __inline int
143 convert_char(FILE *fp, char * mbp, int width, locale_t locale)
144 {
145 	mbstate_t mbs;
146 	size_t nconv;
147 	wint_t wi;
148 	int n;
149 
150 	n = 0;
151 	mbs = initial_mbs;
152 	while (width-- != 0 && (wi = __fgetwc(fp, locale)) != WEOF) {
153 		if (mbp != SUPPRESS_PTR) {
154 			nconv = wcrtomb(mbp, wi, &mbs);
155 			if (nconv == (size_t)-1)
156 				return (-1);
157 			mbp += nconv;
158 		}
159 		n++;
160 	}
161 	if (n == 0)
162 		return (-1);
163 	return (n);
164 }
165 
166 static __inline int
167 convert_wchar(FILE *fp, wchar_t *wcp, int width, locale_t locale)
168 {
169 	wint_t wi;
170 	int n;
171 
172 	n = 0;
173 	while (width-- != 0 && (wi = __fgetwc(fp, locale)) != WEOF) {
174 		if (wcp != SUPPRESS_PTR)
175 			*wcp++ = (wchar_t)wi;
176 		n++;
177 	}
178 	if (n == 0)
179 		return (-1);
180 	return (n);
181 }
182 
183 static __inline int
184 convert_ccl(FILE *fp, char * mbp, int width, const struct ccl *ccl,
185     locale_t locale)
186 {
187 	mbstate_t mbs;
188 	size_t nconv;
189 	wint_t wi;
190 	int n;
191 
192 	n = 0;
193 	mbs = initial_mbs;
194 	while ((wi = __fgetwc(fp, locale)) != WEOF &&
195 	    width-- != 0 && inccl(ccl, wi)) {
196 		if (mbp != SUPPRESS_PTR) {
197 			nconv = wcrtomb(mbp, wi, &mbs);
198 			if (nconv == (size_t)-1)
199 				return (-1);
200 			mbp += nconv;
201 		}
202 		n++;
203 	}
204 	if (wi != WEOF)
205 		__ungetwc(wi, fp, locale);
206 	if (mbp != SUPPRESS_PTR)
207 		*mbp = 0;
208 	return (n);
209 }
210 
211 static __inline int
212 convert_wccl(FILE *fp, wchar_t *wcp, int width, const struct ccl *ccl,
213     locale_t locale)
214 {
215 	wchar_t *wcp0;
216 	wint_t wi;
217 	int n;
218 
219 	if (wcp == SUPPRESS_PTR) {
220 		n = 0;
221 		while ((wi = __fgetwc(fp, locale)) != WEOF &&
222 		    width-- != 0 && inccl(ccl, wi))
223 			n++;
224 		if (wi != WEOF)
225 			__ungetwc(wi, fp, locale);
226 	} else {
227 		wcp0 = wcp;
228 		while ((wi = __fgetwc(fp, locale)) != WEOF &&
229 		    width-- != 0 && inccl(ccl, wi))
230 			*wcp++ = (wchar_t)wi;
231 		if (wi != WEOF)
232 			__ungetwc(wi, fp, locale);
233 		n = wcp - wcp0;
234 		if (n == 0)
235 			return (0);
236 		*wcp = 0;
237 	}
238 	return (n);
239 }
240 
241 static __inline int
242 convert_string(FILE *fp, char * mbp, int width, locale_t locale)
243 {
244 	mbstate_t mbs;
245 	size_t nconv;
246 	wint_t wi;
247 	int nread;
248 
249 	mbs = initial_mbs;
250 	nread = 0;
251 	while ((wi = __fgetwc(fp, locale)) != WEOF && width-- != 0 &&
252 	    !iswspace(wi)) {
253 		if (mbp != SUPPRESS_PTR) {
254 			nconv = wcrtomb(mbp, wi, &mbs);
255 			if (nconv == (size_t)-1)
256 				return (-1);
257 			mbp += nconv;
258 		}
259 		nread++;
260 	}
261 	if (wi != WEOF)
262 		__ungetwc(wi, fp, locale);
263 	if (mbp != SUPPRESS_PTR)
264 		*mbp = 0;
265 	return (nread);
266 }
267 
268 static __inline int
269 convert_wstring(FILE *fp, wchar_t *wcp, int width, locale_t locale)
270 {
271 	wchar_t *wcp0;
272 	wint_t wi;
273 	int nread;
274 
275 	nread = 0;
276 	if (wcp == SUPPRESS_PTR) {
277 		while ((wi = __fgetwc(fp, locale)) != WEOF &&
278 		    width-- != 0 && !iswspace(wi))
279 			nread++;
280 		if (wi != WEOF)
281 			__ungetwc(wi, fp, locale);
282 	} else {
283 		wcp0 = wcp;
284 		while ((wi = __fgetwc(fp, locale)) != WEOF &&
285 		    width-- != 0 && !iswspace(wi)) {
286 			*wcp++ = (wchar_t)wi;
287 			nread++;
288 		}
289 		if (wi != WEOF)
290 			__ungetwc(wi, fp, locale);
291 		*wcp = '\0';
292 	}
293 	return (nread);
294 }
295 
296 /*
297  * Read an integer, storing it in buf.  The only relevant bit in the
298  * flags argument is PFXOK.
299  *
300  * Return 0 on a match failure, and the number of characters read
301  * otherwise.
302  */
303 static __inline int
304 parseint(FILE *fp, wchar_t *buf, int width, int base, int flags,
305     locale_t locale)
306 {
307 	/* `basefix' is used to avoid `if' tests */
308 	static const short basefix[17] =
309 		{ 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
310 	wchar_t *wcp;
311 	int c;
312 
313 	flags |= SIGNOK | NDIGITS | NZDIGITS;
314 	for (wcp = buf; width; width--) {
315 		c = __fgetwc(fp, locale);
316 		/*
317 		 * Switch on the character; `goto ok' if we accept it
318 		 * as a part of number.
319 		 */
320 		switch (c) {
321 
322 		/*
323 		 * The digit 0 is always legal, but is special.  For
324 		 * %i conversions, if no digits (zero or nonzero) have
325 		 * been scanned (only signs), we will have base==0.
326 		 * In that case, we should set it to 8 and enable 0x
327 		 * prefixing.  Also, if we have not scanned zero
328 		 * digits before this, do not turn off prefixing
329 		 * (someone else will turn it off if we have scanned
330 		 * any nonzero digits).
331 		 */
332 		case '0':
333 			if (base == 0) {
334 				base = 8;
335 				flags |= PFXOK;
336 			}
337 			if (flags & NZDIGITS)
338 				flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
339 			else
340 				flags &= ~(SIGNOK|PFXOK|NDIGITS);
341 			goto ok;
342 
343 		/* 1 through 7 always legal */
344 		case '1': case '2': case '3':
345 		case '4': case '5': case '6': case '7':
346 			base = basefix[base];
347 			flags &= ~(SIGNOK | PFXOK | NDIGITS);
348 			goto ok;
349 
350 		/* digits 8 and 9 ok iff decimal or hex */
351 		case '8': case '9':
352 			base = basefix[base];
353 			if (base <= 8)
354 				break;	/* not legal here */
355 			flags &= ~(SIGNOK | PFXOK | NDIGITS);
356 			goto ok;
357 
358 		/* letters ok iff hex */
359 		case 'A': case 'B': case 'C':
360 		case 'D': case 'E': case 'F':
361 		case 'a': case 'b': case 'c':
362 		case 'd': case 'e': case 'f':
363 			/* no need to fix base here */
364 			if (base <= 10)
365 				break;	/* not legal here */
366 			flags &= ~(SIGNOK | PFXOK | NDIGITS);
367 			goto ok;
368 
369 		/* sign ok only as first character */
370 		case '+': case '-':
371 			if (flags & SIGNOK) {
372 				flags &= ~SIGNOK;
373 				flags |= HAVESIGN;
374 				goto ok;
375 			}
376 			break;
377 
378 		/*
379 		 * x ok iff flag still set & 2nd char (or 3rd char if
380 		 * we have a sign).
381 		 */
382 		case 'x': case 'X':
383 			if (flags & PFXOK && wcp ==
384 			    buf + 1 + !!(flags & HAVESIGN)) {
385 				base = 16;	/* if %i */
386 				flags &= ~PFXOK;
387 				goto ok;
388 			}
389 			break;
390 		}
391 
392 		/*
393 		 * If we got here, c is not a legal character for a
394 		 * number.  Stop accumulating digits.
395 		 */
396 		if (c != WEOF)
397 			__ungetwc(c, fp, locale);
398 		break;
399 	ok:
400 		/*
401 		 * c is legal: store it and look at the next.
402 		 */
403 		*wcp++ = (wchar_t)c;
404 	}
405 	/*
406 	 * If we had only a sign, it is no good; push back the sign.
407 	 * If the number ends in `x', it was [sign] '0' 'x', so push
408 	 * back the x and treat it as [sign] '0'.
409 	 */
410 	if (flags & NDIGITS) {
411 		if (wcp > buf)
412 			__ungetwc(*--wcp, fp, locale);
413 		return (0);
414 	}
415 	c = wcp[-1];
416 	if (c == 'x' || c == 'X') {
417 		--wcp;
418 		__ungetwc(c, fp, locale);
419 	}
420 	return (wcp - buf);
421 }
422 
423 /*
424  * MT-safe version.
425  */
426 int
427 vfwscanf_l(FILE * __restrict fp, locale_t locale,
428 		const wchar_t * __restrict fmt, va_list ap)
429 {
430 	int ret;
431 	FIX_LOCALE(locale);
432 
433 	FLOCKFILE_CANCELSAFE(fp);
434 	ORIENT(fp, 1);
435 	ret = __vfwscanf(fp, locale, fmt, ap);
436 	FUNLOCKFILE_CANCELSAFE();
437 	return (ret);
438 }
439 int
440 vfwscanf(FILE * __restrict fp, const wchar_t * __restrict fmt, va_list ap)
441 {
442 	return vfwscanf_l(fp, __get_locale(), fmt, ap);
443 }
444 
445 /*
446  * Non-MT-safe version.
447  */
448 int
449 __vfwscanf(FILE * __restrict fp, locale_t locale,
450 		const wchar_t * __restrict fmt, va_list ap)
451 {
452 #define	GETARG(type)	((flags & SUPPRESS) ? SUPPRESS_PTR : va_arg(ap, type))
453 	wint_t c;		/* character from format, or conversion */
454 	size_t width;		/* field width, or 0 */
455 	int flags;		/* flags as defined above */
456 	int nassigned;		/* number of fields assigned */
457 	int nconversions;	/* number of conversions */
458 	int nr;			/* characters read by the current conversion */
459 	int nread;		/* number of characters consumed from fp */
460 	int base;		/* base argument to conversion function */
461 	struct ccl ccl;		/* character class info */
462 	wchar_t buf[BUF];	/* buffer for numeric conversions */
463 	wint_t wi;		/* handy wint_t */
464 
465 	nassigned = 0;
466 	nconversions = 0;
467 	nread = 0;
468 	ccl.start = ccl.end = NULL;
469 	for (;;) {
470 		c = *fmt++;
471 		if (c == 0)
472 			return (nassigned);
473 		if (iswspace(c)) {
474 			while ((c = __fgetwc(fp, locale)) != WEOF &&
475 			    iswspace_l(c, locale))
476 				nread++;
477 			if (c != WEOF)
478 				__ungetwc(c, fp, locale);
479 			continue;
480 		}
481 		if (c != '%')
482 			goto literal;
483 		width = 0;
484 		flags = 0;
485 		/*
486 		 * switch on the format.  continue if done;
487 		 * break once format type is derived.
488 		 */
489 again:		c = *fmt++;
490 		switch (c) {
491 		case '%':
492 literal:
493 			if ((wi = __fgetwc(fp, locale)) == WEOF)
494 				goto input_failure;
495 			if (wi != c) {
496 				__ungetwc(wi, fp, locale);
497 				goto match_failure;
498 			}
499 			nread++;
500 			continue;
501 
502 		case '*':
503 			flags |= SUPPRESS;
504 			goto again;
505 		case 'j':
506 			flags |= INTMAXT;
507 			goto again;
508 		case 'l':
509 			if (flags & LONG) {
510 				flags &= ~LONG;
511 				flags |= LONGLONG;
512 			} else
513 				flags |= LONG;
514 			goto again;
515 		case 'q':
516 			flags |= LONGLONG;	/* not quite */
517 			goto again;
518 		case 't':
519 			flags |= PTRDIFFT;
520 			goto again;
521 		case 'z':
522 			flags |= SIZET;
523 			goto again;
524 		case 'L':
525 			flags |= LONGDBL;
526 			goto again;
527 		case 'h':
528 			if (flags & SHORT) {
529 				flags &= ~SHORT;
530 				flags |= SHORTSHORT;
531 			} else
532 				flags |= SHORT;
533 			goto again;
534 
535 		case '0': case '1': case '2': case '3': case '4':
536 		case '5': case '6': case '7': case '8': case '9':
537 			width = width * 10 + c - '0';
538 			goto again;
539 
540 		/*
541 		 * Conversions.
542 		 */
543 		case 'd':
544 			c = CT_INT;
545 			base = 10;
546 			break;
547 
548 		case 'i':
549 			c = CT_INT;
550 			base = 0;
551 			break;
552 
553 		case 'o':
554 			c = CT_INT;
555 			flags |= UNSIGNED;
556 			base = 8;
557 			break;
558 
559 		case 'u':
560 			c = CT_INT;
561 			flags |= UNSIGNED;
562 			base = 10;
563 			break;
564 
565 		case 'X':
566 		case 'x':
567 			flags |= PFXOK;	/* enable 0x prefixing */
568 			c = CT_INT;
569 			flags |= UNSIGNED;
570 			base = 16;
571 			break;
572 
573 #ifndef NO_FLOATING_POINT
574 		case 'A': case 'E': case 'F': case 'G':
575 		case 'a': case 'e': case 'f': case 'g':
576 			c = CT_FLOAT;
577 			break;
578 #endif
579 
580 		case 'S':
581 			flags |= LONG;
582 			/* FALLTHROUGH */
583 		case 's':
584 			c = CT_STRING;
585 			break;
586 
587 		case '[':
588 			ccl.start = fmt;
589 			if (*fmt == '^') {
590 				ccl.compl = 1;
591 				fmt++;
592 			} else
593 				ccl.compl = 0;
594 			if (*fmt == ']')
595 				fmt++;
596 			while (*fmt != '\0' && *fmt != ']')
597 				fmt++;
598 			ccl.end = fmt;
599 			fmt++;
600 			flags |= NOSKIP;
601 			c = CT_CCL;
602 			break;
603 
604 		case 'C':
605 			flags |= LONG;
606 			/* FALLTHROUGH */
607 		case 'c':
608 			flags |= NOSKIP;
609 			c = CT_CHAR;
610 			break;
611 
612 		case 'p':	/* pointer format is like hex */
613 			flags |= POINTER | PFXOK;
614 			c = CT_INT;		/* assumes sizeof(uintmax_t) */
615 			flags |= UNSIGNED;	/*      >= sizeof(uintptr_t) */
616 			base = 16;
617 			break;
618 
619 		case 'n':
620 			if (flags & SUPPRESS)	/* ??? */
621 				continue;
622 			if (flags & SHORTSHORT)
623 				*va_arg(ap, char *) = nread;
624 			else if (flags & SHORT)
625 				*va_arg(ap, short *) = nread;
626 			else if (flags & LONG)
627 				*va_arg(ap, long *) = nread;
628 			else if (flags & LONGLONG)
629 				*va_arg(ap, long long *) = nread;
630 			else if (flags & INTMAXT)
631 				*va_arg(ap, intmax_t *) = nread;
632 			else if (flags & SIZET)
633 				*va_arg(ap, size_t *) = nread;
634 			else if (flags & PTRDIFFT)
635 				*va_arg(ap, ptrdiff_t *) = nread;
636 			else
637 				*va_arg(ap, int *) = nread;
638 			continue;
639 
640 		default:
641 			goto match_failure;
642 
643 		/*
644 		 * Disgusting backwards compatibility hack.	XXX
645 		 */
646 		case '\0':	/* compat */
647 			return (EOF);
648 		}
649 
650 		/*
651 		 * Consume leading white space, except for formats
652 		 * that suppress this.
653 		 */
654 		if ((flags & NOSKIP) == 0) {
655 			while ((wi = __fgetwc(fp, locale)) != WEOF && iswspace(wi))
656 				nread++;
657 			if (wi == WEOF)
658 				goto input_failure;
659 			__ungetwc(wi, fp, locale);
660 		}
661 
662 		/*
663 		 * Do the conversion.
664 		 */
665 		switch (c) {
666 
667 		case CT_CHAR:
668 			/* scan arbitrary characters (sets NOSKIP) */
669 			if (width == 0)
670 				width = 1;
671 			if (flags & LONG) {
672 				nr = convert_wchar(fp, GETARG(wchar_t *), width,
673 				    locale);
674 			} else {
675 				nr = convert_char(fp, GETARG(char *), width,
676 				    locale);
677 			}
678 			if (nr < 0)
679 				goto input_failure;
680 			break;
681 
682 		case CT_CCL:
683 			/* scan a (nonempty) character class (sets NOSKIP) */
684 			if (width == 0)
685 				width = (size_t)~0;	/* `infinity' */
686 			/* take only those things in the class */
687 			if (flags & LONG) {
688 				nr = convert_wccl(fp, GETARG(wchar_t *), width,
689 				    &ccl, locale);
690 			} else {
691 				nr = convert_ccl(fp, GETARG(char *), width,
692 				    &ccl, locale);
693 			}
694 			if (nr <= 0) {
695 				if (nr < 0)
696 					goto input_failure;
697 				else /* nr == 0 */
698 					goto match_failure;
699 			}
700 			break;
701 
702 		case CT_STRING:
703 			/* like CCL, but zero-length string OK, & no NOSKIP */
704 			if (width == 0)
705 				width = (size_t)~0;
706 			if (flags & LONG) {
707 				nr = convert_wstring(fp, GETARG(wchar_t *),
708 				    width, locale);
709 			} else {
710 				nr = convert_string(fp, GETARG(char *), width,
711 				    locale);
712 			}
713 			if (nr < 0)
714 				goto input_failure;
715 			break;
716 
717 		case CT_INT:
718 			/* scan an integer as if by the conversion function */
719 			if (width == 0 || width > sizeof(buf) /
720 			    sizeof(*buf) - 1)
721 				width = sizeof(buf) / sizeof(*buf) - 1;
722 
723 			nr = parseint(fp, buf, width, base, flags, locale);
724 			if (nr == 0)
725 				goto match_failure;
726 			if ((flags & SUPPRESS) == 0) {
727 				uintmax_t res;
728 
729 				buf[nr] = L'\0';
730 				if ((flags & UNSIGNED) == 0)
731 				    res = wcstoimax(buf, NULL, base);
732 				else
733 				    res = wcstoumax(buf, NULL, base);
734 				if (flags & POINTER)
735 					*va_arg(ap, void **) =
736 							(void *)(uintptr_t)res;
737 				else if (flags & SHORTSHORT)
738 					*va_arg(ap, char *) = res;
739 				else if (flags & SHORT)
740 					*va_arg(ap, short *) = res;
741 				else if (flags & LONG)
742 					*va_arg(ap, long *) = res;
743 				else if (flags & LONGLONG)
744 					*va_arg(ap, long long *) = res;
745 				else if (flags & INTMAXT)
746 					*va_arg(ap, intmax_t *) = res;
747 				else if (flags & PTRDIFFT)
748 					*va_arg(ap, ptrdiff_t *) = res;
749 				else if (flags & SIZET)
750 					*va_arg(ap, size_t *) = res;
751 				else
752 					*va_arg(ap, int *) = res;
753 			}
754 			break;
755 
756 #ifndef NO_FLOATING_POINT
757 		case CT_FLOAT:
758 			/* scan a floating point number as if by strtod */
759 			if (width == 0 || width > sizeof(buf) /
760 			    sizeof(*buf) - 1)
761 				width = sizeof(buf) / sizeof(*buf) - 1;
762 			nr = parsefloat(fp, buf, buf + width, locale);
763 			if (nr == 0)
764 				goto match_failure;
765 			if ((flags & SUPPRESS) == 0) {
766 				if (flags & LONGDBL) {
767 					long double res = wcstold(buf, NULL);
768 					*va_arg(ap, long double *) = res;
769 				} else if (flags & LONG) {
770 					double res = wcstod(buf, NULL);
771 					*va_arg(ap, double *) = res;
772 				} else {
773 					float res = wcstof(buf, NULL);
774 					*va_arg(ap, float *) = res;
775 				}
776 			}
777 			break;
778 #endif /* !NO_FLOATING_POINT */
779 		}
780 		if (!(flags & SUPPRESS))
781 			nassigned++;
782 		nread += nr;
783 		nconversions++;
784 	}
785 input_failure:
786 	return (nconversions != 0 ? nassigned : EOF);
787 match_failure:
788 	return (nassigned);
789 }
790 
791 #ifndef NO_FLOATING_POINT
792 static int
793 parsefloat(FILE *fp, wchar_t *buf, wchar_t *end, locale_t locale)
794 {
795 	mbstate_t mbs;
796 	size_t nconv;
797 	wchar_t *commit, *p;
798 	int infnanpos = 0;
799 	enum {
800 		S_START, S_GOTSIGN, S_INF, S_NAN, S_DONE, S_MAYBEHEX,
801 		S_DIGITS, S_FRAC, S_EXP, S_EXPDIGITS
802 	} state = S_START;
803 	wchar_t c;
804 	wchar_t decpt;
805 	_Bool gotmantdig = 0, ishex = 0;
806 
807 	mbs = initial_mbs;
808 	nconv = mbrtowc(&decpt, localeconv()->decimal_point, MB_CUR_MAX, &mbs);
809 	if (nconv == (size_t)-1 || nconv == (size_t)-2)
810 		decpt = '.';	/* failsafe */
811 
812 	/*
813 	 * We set commit = p whenever the string we have read so far
814 	 * constitutes a valid representation of a floating point
815 	 * number by itself.  At some point, the parse will complete
816 	 * or fail, and we will ungetc() back to the last commit point.
817 	 * To ensure that the file offset gets updated properly, it is
818 	 * always necessary to read at least one character that doesn't
819 	 * match; thus, we can't short-circuit "infinity" or "nan(...)".
820 	 */
821 	commit = buf - 1;
822 	c = WEOF;
823 	for (p = buf; p < end; ) {
824 		if ((c = __fgetwc(fp, locale)) == WEOF)
825 			break;
826 reswitch:
827 		switch (state) {
828 		case S_START:
829 			state = S_GOTSIGN;
830 			if (c == '-' || c == '+')
831 				break;
832 			else
833 				goto reswitch;
834 		case S_GOTSIGN:
835 			switch (c) {
836 			case '0':
837 				state = S_MAYBEHEX;
838 				commit = p;
839 				break;
840 			case 'I':
841 			case 'i':
842 				state = S_INF;
843 				break;
844 			case 'N':
845 			case 'n':
846 				state = S_NAN;
847 				break;
848 			default:
849 				state = S_DIGITS;
850 				goto reswitch;
851 			}
852 			break;
853 		case S_INF:
854 			if (infnanpos > 6 ||
855 			    (c != "nfinity"[infnanpos] &&
856 			     c != "NFINITY"[infnanpos]))
857 				goto parsedone;
858 			if (infnanpos == 1 || infnanpos == 6)
859 				commit = p;	/* inf or infinity */
860 			infnanpos++;
861 			break;
862 		case S_NAN:
863 			switch (infnanpos) {
864 			case 0:
865 				if (c != 'A' && c != 'a')
866 					goto parsedone;
867 				break;
868 			case 1:
869 				if (c != 'N' && c != 'n')
870 					goto parsedone;
871 				else
872 					commit = p;
873 				break;
874 			case 2:
875 				if (c != '(')
876 					goto parsedone;
877 				break;
878 			default:
879 				if (c == ')') {
880 					commit = p;
881 					state = S_DONE;
882 				} else if (!iswalnum(c) && c != '_')
883 					goto parsedone;
884 				break;
885 			}
886 			infnanpos++;
887 			break;
888 		case S_DONE:
889 			goto parsedone;
890 		case S_MAYBEHEX:
891 			state = S_DIGITS;
892 			if (c == 'X' || c == 'x') {
893 				ishex = 1;
894 				break;
895 			} else {	/* we saw a '0', but no 'x' */
896 				gotmantdig = 1;
897 				goto reswitch;
898 			}
899 		case S_DIGITS:
900 			if ((ishex && iswxdigit(c)) || iswdigit(c))
901 				gotmantdig = 1;
902 			else {
903 				state = S_FRAC;
904 				if (c != decpt)
905 					goto reswitch;
906 			}
907 			if (gotmantdig)
908 				commit = p;
909 			break;
910 		case S_FRAC:
911 			if (((c == 'E' || c == 'e') && !ishex) ||
912 			    ((c == 'P' || c == 'p') && ishex)) {
913 				if (!gotmantdig)
914 					goto parsedone;
915 				else
916 					state = S_EXP;
917 			} else if ((ishex && iswxdigit(c)) || iswdigit(c)) {
918 				commit = p;
919 				gotmantdig = 1;
920 			} else
921 				goto parsedone;
922 			break;
923 		case S_EXP:
924 			state = S_EXPDIGITS;
925 			if (c == '-' || c == '+')
926 				break;
927 			else
928 				goto reswitch;
929 		case S_EXPDIGITS:
930 			if (iswdigit(c))
931 				commit = p;
932 			else
933 				goto parsedone;
934 			break;
935 		default:
936 			abort();
937 		}
938 		*p++ = c;
939 		c = WEOF;
940 	}
941 
942 parsedone:
943 	if (c != WEOF)
944 		__ungetwc(c, fp, locale);
945 	while (commit < --p)
946 		__ungetwc(*p, fp, locale);
947 	*++commit = '\0';
948 	return (commit - buf);
949 }
950 #endif
951