xref: /netbsd-src/lib/libc/stdio/vfwprintf.c (revision 5f2f42719cd62ff11fd913b40b7ce19f07c4fd25)
1 /*	$NetBSD: vfwprintf.c,v 1.39 2022/04/19 20:32:16 rillig Exp $	*/
2 
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  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #if 0
38 static char sccsid[] = "@(#)vfprintf.c	8.1 (Berkeley) 6/4/93";
39 __FBSDID("$FreeBSD: src/lib/libc/stdio/vfwprintf.c,v 1.27 2007/01/09 00:28:08 imp Exp $");
40 #else
41 __RCSID("$NetBSD: vfwprintf.c,v 1.39 2022/04/19 20:32:16 rillig Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 /*
46  * Actual {w,}printf innards.
47  */
48 
49 #include "namespace.h"
50 #include <sys/types.h>
51 
52 #include <assert.h>
53 #include <ctype.h>
54 #include <limits.h>
55 #include <locale.h>
56 #include <stdarg.h>
57 #include <stddef.h>
58 #include <stdint.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <errno.h>
63 #include <wchar.h>
64 #include <wctype.h>
65 
66 #include "reentrant.h"
67 #include "setlocale_local.h"
68 #include "local.h"
69 #include "extern.h"
70 #include "fvwrite.h"
71 
72 #ifndef NARROW
73 #define MCHAR_T		char
74 #define CHAR_T		wchar_t
75 #define STRLEN(a)	wcslen(a)
76 #define MEMCHR(a, b, c)	wmemchr(a, b, c)
77 #define SCONV(a, b, loc)	__mbsconv(a, b, loc)
78 #define STRCONST(a)	L ## a
79 #define WDECL(a, b)	a ## w ## b
80 #define END_OF_FILE	WEOF
81 #define MULTI		0
82 #else
83 #define MCHAR_T		wchar_t
84 #define CHAR_T		char
85 #define STRLEN(a)	strlen(a)
86 #define MEMCHR(a, b, c)	memchr(a, b, c)
87 #define SCONV(a, b, loc)	__wcsconv(a, b, loc)
88 #define STRCONST(a)	a
89 #define WDECL(a, b)	a ## b
90 #define END_OF_FILE	EOF
91 #define MULTI		LONGINT
92 #endif
93 
94 union arg {
95 	int	intarg;
96 	u_int	uintarg;
97 	long	longarg;
98 	u_long	ulongarg;
99 	long long longlongarg;
100 	unsigned long long ulonglongarg;
101 	ptrdiff_t ptrdiffarg;
102 	ssize_t ssizearg;
103 	size_t	sizearg;
104 	intmax_t intmaxarg;
105 	uintmax_t uintmaxarg;
106 	void	*pvoidarg;
107 	char	*pchararg;
108 	signed char *pschararg;
109 	short	*pshortarg;
110 	int	*pintarg;
111 	long	*plongarg;
112 	long long *plonglongarg;
113 	ptrdiff_t *pptrdiffarg;
114 	size_t	*psizearg;
115 	intmax_t *pintmaxarg;
116 #ifndef NO_FLOATING_POINT
117 	double	doublearg;
118 	long double longdoublearg;
119 #endif
120 	wint_t	wintarg;
121 	wchar_t	*pwchararg;
122 };
123 
124 /*
125  * Type ids for argument type table.
126  */
127 enum typeid {
128 	T_UNUSED = 0, TP_SHORT, T_INT, T_U_INT, TP_INT,
129 	T_LONG, T_U_LONG, TP_LONG, T_LLONG, T_U_LLONG, TP_LLONG,
130 	T_PTRDIFFT, TP_PTRDIFFT, T_SSIZET, T_SIZET, TP_SIZET,
131 	T_INTMAXT, T_UINTMAXT, TP_INTMAXT, TP_VOID, TP_CHAR, TP_SCHAR,
132 	T_DOUBLE, T_LONG_DOUBLE, T_WINT, TP_WCHAR
133 };
134 
135 #ifdef NARROW
136 __printflike(3, 0)
137 #endif
138 static int	__sbprintf(FILE *, locale_t, const CHAR_T *, va_list);
139 
140 static CHAR_T	*__ujtoa(uintmax_t, CHAR_T *, int, int, const char *, int,
141 		    char, const char *);
142 static CHAR_T	*__ultoa(u_long, CHAR_T *, int, int, const char *, int,
143 		    char, const char *);
144 #ifndef NARROW
145 static CHAR_T	*__mbsconv(char *, int, locale_t);
146 static wint_t	__xfputwc(CHAR_T, FILE *, locale_t);
147 #else
148 static char	*__wcsconv(wchar_t *, int, locale_t);
149 static int	__sprint(FILE *, struct __suio *);
150 #endif
151 static int	__find_arguments(const CHAR_T *, va_list, union arg **);
152 static int	__grow_type_table(size_t, enum typeid **, size_t *);
153 
154 /*
155  * Helper function for `fprintf to unbuffered unix file': creates a
156  * temporary buffer.  We only work on write-only files; this avoids
157  * worries about ungetc buffers and so forth.
158  */
159 static int
160 __sbprintf(FILE *fp, locale_t loc, const CHAR_T *fmt, va_list ap)
161 {
162 	int ret;
163 	FILE fake;
164 	struct __sfileext fakeext;
165 	unsigned char buf[BUFSIZ];
166 
167 	_DIAGASSERT(fp != NULL);
168 	_DIAGASSERT(fmt != NULL);
169 
170 	_FILEEXT_SETUP(&fake, &fakeext);
171 	memset(WCIO_GET(&fake), 0, sizeof(struct wchar_io_data));
172 
173 	/* copy the important variables */
174 	fake._flags = fp->_flags & ~__SNBF;
175 	fake._file = fp->_file;
176 	fake._cookie = fp->_cookie;
177 	fake._write = fp->_write;
178 	fake._flush = fp->_flush;
179 
180 	/* set up the buffer */
181 	fake._bf._base = fake._p = buf;
182 	fake._bf._size = fake._w = sizeof(buf);
183 	fake._lbfsize = 0;	/* not actually used, but Just In Case */
184 
185 	/* do the work, then copy any error status */
186 	ret = WDECL(__vf,printf_unlocked_l)(&fake, loc, fmt, ap);
187 	if (ret >= 0 && fflush(&fake))
188 		ret = END_OF_FILE;
189 	if (fake._flags & __SERR)
190 		fp->_flags |= __SERR;
191 	return ret;
192 }
193 
194 #ifndef NARROW
195 /*
196  * Like __fputwc, but handles fake string (__SSTR) files properly.
197  * File must already be locked.
198  */
199 static wint_t
200 __xfputwc(wchar_t wc, FILE *fp, locale_t loc)
201 {
202 	static const mbstate_t initial;
203 	mbstate_t mbs;
204 	char buf[MB_LEN_MAX];
205 	struct __suio uio;
206 	struct __siov iov;
207 	size_t len;
208 
209 	if ((fp->_flags & __SSTR) == 0)
210 		return __fputwc_unlock(wc, fp);
211 
212 	mbs = initial;
213 	if ((len = wcrtomb_l(buf, wc, &mbs, loc)) == (size_t)-1) {
214 		fp->_flags |= __SERR;
215 		return END_OF_FILE;
216 	}
217 	uio.uio_iov = &iov;
218 	uio.uio_resid = len;
219 	uio.uio_iovcnt = 1;
220 	iov.iov_base = buf;
221 	iov.iov_len = len;
222 	return __sfvwrite(fp, &uio) != EOF ? (wint_t)wc : END_OF_FILE;
223 }
224 #else
225 /*
226  * Flush out all the vectors defined by the given uio,
227  * then reset it so that it can be reused.
228  */
229 static int
230 __sprint(FILE *fp, struct __suio *uio)
231 {
232 	int err;
233 
234 	_DIAGASSERT(fp != NULL);
235 	_DIAGASSERT(uio != NULL);
236 
237 	if (uio->uio_resid == 0) {
238 		uio->uio_iovcnt = 0;
239 		return 0;
240 	}
241 	err = __sfvwrite(fp, uio);
242 	uio->uio_resid = 0;
243 	uio->uio_iovcnt = 0;
244 	return err;
245 }
246 #endif
247 
248 /*
249  * Macros for converting digits to letters and vice versa
250  */
251 #define	to_digit(c)	((c) - '0')
252 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
253 #define	to_char(n)	(CHAR_T)((n) + '0')
254 
255 /*
256  * Convert an unsigned long to ASCII for printf purposes, returning
257  * a pointer to the first character of the string representation.
258  * Octal numbers can be forced to have a leading zero; hex numbers
259  * use the given digits.
260  */
261 static CHAR_T *
262 __ultoa(u_long val, CHAR_T *endp, int base, int octzero, const char *xdigs,
263     int needgrp, char thousep, const char *grp)
264 {
265 	CHAR_T *cp = endp;
266 	long sval;
267 	int ndig;
268 
269 	/*
270 	 * Handle the three cases separately, in the hope of getting
271 	 * better/faster code.
272 	 */
273 	switch (base) {
274 	case 10:
275 		if (val < 10) {	/* many numbers are 1 digit */
276 			*--cp = to_char(val);
277 			return cp;
278 		}
279 		ndig = 0;
280 		/*
281 		 * On many machines, unsigned arithmetic is harder than
282 		 * signed arithmetic, so we do at most one unsigned mod and
283 		 * divide; this is sufficient to reduce the range of
284 		 * the incoming value to where signed arithmetic works.
285 		 */
286 		if (val > LONG_MAX) {
287 			*--cp = to_char(val % 10);
288 			ndig++;
289 			sval = val / 10;
290 		} else
291 			sval = val;
292 		do {
293 			*--cp = to_char(sval % 10);
294 			ndig++;
295 			/*
296 			 * If (*grp == CHAR_MAX) then no more grouping
297 			 * should be performed.
298 			 */
299 			if (needgrp && ndig == *grp
300 			    && (unsigned char)*grp != (unsigned char)CHAR_MAX
301 			    && sval > 9) {
302 				*--cp = thousep;
303 				ndig = 0;
304 				/*
305 				 * If (*(grp+1) == '\0') then we have to
306 				 * use *grp character (last grouping rule)
307 				 * for all next cases
308 				 */
309 				if (*(grp+1) != '\0')
310 					grp++;
311 			}
312 			sval /= 10;
313 		} while (sval != 0);
314 		break;
315 
316 	case 8:
317 		do {
318 			*--cp = to_char(val & 7);
319 			val >>= 3;
320 		} while (val);
321 		if (octzero && *cp != '0')
322 			*--cp = '0';
323 		break;
324 
325 	case 16:
326 		do {
327 			*--cp = xdigs[(size_t)val & 15];
328 			val >>= 4;
329 		} while (val);
330 		break;
331 
332 	default:			/* oops */
333 		abort();
334 	}
335 	return cp;
336 }
337 
338 /* Identical to __ultoa, but for intmax_t. */
339 static CHAR_T *
340 __ujtoa(uintmax_t val, CHAR_T *endp, int base, int octzero,
341     const char *xdigs, int needgrp, char thousep, const char *grp)
342 {
343 	CHAR_T *cp = endp;
344 	intmax_t sval;
345 	int ndig;
346 
347 	/* quick test for small values; __ultoa is typically much faster */
348 	/* (perhaps instead we should run until small, then call __ultoa?) */
349 	if (val <= ULONG_MAX)
350 		return __ultoa((u_long)val, endp, base, octzero, xdigs,
351 		    needgrp, thousep, grp);
352 	switch (base) {
353 	case 10:
354 		if (val < 10) {
355 			*--cp = to_char(val % 10);
356 			return cp;
357 		}
358 		ndig = 0;
359 		if (val > INTMAX_MAX) {
360 			*--cp = to_char(val % 10);
361 			ndig++;
362 			sval = val / 10;
363 		} else
364 			sval = val;
365 		do {
366 			*--cp = to_char(sval % 10);
367 			ndig++;
368 			/*
369 			 * If (*grp == CHAR_MAX) then no more grouping
370 			 * should be performed.
371 			 */
372 			if (needgrp
373 			    && (unsigned char)*grp != (unsigned char)CHAR_MAX
374 			    && ndig == *grp
375 			    && sval > 9) {
376 				*--cp = thousep;
377 				ndig = 0;
378 				/*
379 				 * If (*(grp+1) == '\0') then we have to
380 				 * use *grp character (last grouping rule)
381 				 * for all next cases
382 				 */
383 				if (*(grp+1) != '\0')
384 					grp++;
385 			}
386 			sval /= 10;
387 		} while (sval != 0);
388 		break;
389 
390 	case 8:
391 		do {
392 			*--cp = to_char(val & 7);
393 			val >>= 3;
394 		} while (val);
395 		if (octzero && *cp != '0')
396 			*--cp = '0';
397 		break;
398 
399 	case 16:
400 		do {
401 			*--cp = xdigs[(size_t)val & 15];
402 			val >>= 4;
403 		} while (val);
404 		break;
405 
406 	default:
407 		abort();
408 	}
409 	return cp;
410 }
411 
412 #ifndef NARROW
413 /*
414  * Convert a multibyte character string argument for the %s format to a wide
415  * string representation. ``prec'' specifies the maximum number of bytes
416  * to output. If ``prec'' is greater than or equal to zero, we can't assume
417  * that the multibyte char. string ends in a null character.
418  */
419 static wchar_t *
420 __mbsconv(char *mbsarg, int prec, locale_t loc)
421 {
422 	static const mbstate_t initial;
423 	mbstate_t mbs;
424 	wchar_t *convbuf, *wcp;
425 	const char *p;
426 	size_t insize, nchars, nconv;
427 
428 	if (mbsarg == NULL)
429 		return NULL;
430 
431 	/*
432 	 * Supplied argument is a multibyte string; convert it to wide
433 	 * characters first.
434 	 */
435 	if (prec >= 0) {
436 		/*
437 		 * String is not guaranteed to be NUL-terminated. Find the
438 		 * number of characters to print.
439 		 */
440 		p = mbsarg;
441 		insize = nchars = nconv = 0;
442 		mbs = initial;
443 		while (nchars != (size_t)prec) {
444 			nconv = mbrlen_l(p, MB_CUR_MAX_L(loc), &mbs, loc);
445 			if (nconv == 0 || nconv == (size_t)-1 ||
446 			    nconv == (size_t)-2)
447 				break;
448 			p += nconv;
449 			nchars++;
450 			insize += nconv;
451 		}
452 		if (nconv == (size_t)-1 || nconv == (size_t)-2)
453 			return NULL;
454 	} else
455 		insize = strlen(mbsarg);
456 
457 	/*
458 	 * Allocate buffer for the result and perform the conversion,
459 	 * converting at most `size' bytes of the input multibyte string to
460 	 * wide characters for printing.
461 	 */
462 	convbuf = NULL;
463 	errno = reallocarr(&convbuf, insize + 1, sizeof(*convbuf));
464 	if (errno)
465 		return NULL;
466 	wcp = convbuf;
467 	p = mbsarg;
468 	mbs = initial;
469 	nconv = 0;
470 	while (insize != 0) {
471 		nconv = mbrtowc_l(wcp, p, insize, &mbs, loc);
472 		if (nconv == 0 || nconv == (size_t)-1 || nconv == (size_t)-2)
473 			break;
474 		wcp++;
475 		p += nconv;
476 		insize -= nconv;
477 	}
478 	if (nconv == (size_t)-1 || nconv == (size_t)-2) {
479 		int serrno = errno;
480 		free(convbuf);
481 		errno = serrno;
482 		return NULL;
483 	}
484 	*wcp = L'\0';
485 
486 	return convbuf;
487 }
488 #else
489 /*
490  * Convert a wide-character string argument for the %ls format to a multibyte
491  * string representation. If not -1, prec specifies the maximum number of
492  * bytes to output, and also means that we can't assume that the wide-char.
493  * string ends is null-terminated.
494  */
495 static char *
496 __wcsconv(wchar_t *wcsarg, int prec, locale_t loc)
497 {
498 	static const mbstate_t initial;
499 	mbstate_t mbs;
500 	char buf[MB_LEN_MAX];
501 	wchar_t *p;
502 	char *convbuf;
503 	size_t clen, nbytes;
504 
505 	/* Allocate space for the maximum number of bytes we could output. */
506 	if (prec < 0) {
507 		p = wcsarg;
508 		mbs = initial;
509 		nbytes = wcsrtombs_l(NULL, (void *)&p, 0, &mbs, loc);
510 		if (nbytes == (size_t)-1)
511 			return NULL;
512 	} else {
513 		/*
514 		 * Optimisation: if the output precision is small enough,
515 		 * just allocate enough memory for the maximum instead of
516 		 * scanning the string.
517 		 */
518 		if (prec < 128)
519 			nbytes = prec;
520 		else {
521 			nbytes = 0;
522 			p = wcsarg;
523 			mbs = initial;
524 			for (;;) {
525 				clen = wcrtomb_l(buf, *p++, &mbs, loc);
526 				if (clen == 0 || clen == (size_t)-1 ||
527 				    nbytes + clen > (size_t)prec)
528 					break;
529 				nbytes += clen;
530 			}
531 		}
532 	}
533 	if ((convbuf = malloc(nbytes + 1)) == NULL)
534 		return NULL;
535 
536 	/* Fill the output buffer. */
537 	p = wcsarg;
538 	mbs = initial;
539 	if ((nbytes = wcsrtombs_l(convbuf, (void *)&p,
540 	    nbytes, &mbs, loc)) == (size_t)-1) {
541 		free(convbuf);
542 		return NULL;
543 	}
544 	convbuf[nbytes] = '\0';
545 	return convbuf;
546 }
547 #endif
548 
549 /*
550  * MT-safe version
551  */
552 int
553 WDECL(vf,printf)(FILE * __restrict fp, const CHAR_T * __restrict fmt0, va_list ap)
554 {
555 	int ret;
556 
557 	FLOCKFILE(fp);
558 	ret = WDECL(__vf,printf_unlocked_l)(fp, _current_locale(), fmt0, ap);
559 	FUNLOCKFILE(fp);
560 	return ret;
561 }
562 
563 int
564 WDECL(vf,printf_l)(FILE * __restrict fp, locale_t loc, const CHAR_T * __restrict fmt0,
565     va_list ap)
566 {
567 	int ret;
568 
569 	FLOCKFILE(fp);
570 	ret = WDECL(__vf,printf_unlocked_l)(fp, loc, fmt0, ap);
571 	FUNLOCKFILE(fp);
572 	return ret;
573 }
574 
575 #ifndef NO_FLOATING_POINT
576 
577 #include <float.h>
578 #include <math.h>
579 #include "floatio.h"
580 
581 #define	DEFPREC		6
582 
583 static int exponent(CHAR_T *, int, int);
584 #ifndef WIDE_DOUBLE
585 static char *cvt(double, int, int, char *, int *, int, int *);
586 #endif
587 
588 #endif /* !NO_FLOATING_POINT */
589 
590 /*
591  * The size of the buffer we use as scratch space for integer
592  * conversions, among other things.  Technically, we would need the
593  * most space for base 10 conversions with thousands' grouping
594  * characters between each pair of digits.  100 bytes is a
595  * conservative overestimate even for a 128-bit uintmax_t.
596  */
597 #define	BUF	100
598 
599 #define STATIC_ARG_TBL_SIZE 8           /* Size of static argument table. */
600 
601 /*
602  * Flags used during conversion.
603  */
604 #define	ALT		0x001		/* alternate form */
605 #define	LADJUST		0x004		/* left adjustment */
606 #define	LONGDBL		0x008		/* long double */
607 #define	LONGINT		0x010		/* long integer */
608 #define	LLONGINT	0x020		/* long long integer */
609 #define	SHORTINT	0x040		/* short integer */
610 #define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
611 #define	FPT		0x100		/* Floating point number */
612 #define	GROUPING	0x200		/* use grouping ("'" flag) */
613 					/* C99 additional size modifiers: */
614 #define	SIZET		0x400		/* size_t */
615 #define	PTRDIFFT	0x800		/* ptrdiff_t */
616 #define	INTMAXT		0x1000		/* intmax_t */
617 #define	CHARINT		0x2000		/* print char using int format */
618 
619 /*
620  * Non-MT-safe version
621  */
622 int
623 WDECL(__vf,printf_unlocked_l)(FILE *fp, locale_t loc, const CHAR_T *fmt0, va_list ap)
624 {
625 	CHAR_T *fmt;		/* format string */
626 	int ch;			/* character from fmt */
627 	int n, n2;		/* handy integer (short term usage) */
628 	CHAR_T *cp;		/* handy char pointer (short term usage) */
629 	int flags;		/* flags as above */
630 	int ret;		/* return value accumulator */
631 	int width;		/* width from format (%8d), or 0 */
632 	int prec;		/* precision from format; <0 for N/A */
633 	CHAR_T sign;		/* sign prefix (' ', '+', '-', or \0) */
634 	char thousands_sep;	/* locale specific thousands separator */
635 	const char *grouping;	/* locale specific numeric grouping rules */
636 #ifndef NO_FLOATING_POINT
637 	/*
638 	 * We can decompose the printed representation of floating
639 	 * point numbers into several parts, some of which may be empty:
640 	 *
641 	 * [+|-| ] [0x|0X] MMM . NNN [e|E|p|P] [+|-] ZZ
642 	 *    A       B     ---C---      D       E   F
643 	 *
644 	 * A:	'sign' holds this value if present; '\0' otherwise
645 	 * B:	ox[1] holds the 'x' or 'X'; '\0' if not hexadecimal
646 	 * C:	cp points to the string MMMNNN.  Leading and trailing
647 	 *	zeros are not in the string and must be added.
648 	 * D:	expchar holds this character; '\0' if no exponent, e.g. %f
649 	 * F:	at least two digits for decimal, at least one digit for hex
650 	 */
651 	char *decimal_point;	/* locale specific decimal point */
652 #ifdef WIDE_DOUBLE
653 	int signflag;		/* true if float is negative */
654 	union {			/* floating point arguments %[aAeEfFgG] */
655 		double dbl;
656 		long double ldbl;
657 	} fparg;
658 	char *dtoaend;		/* pointer to end of converted digits */
659 #else
660 	double _double;		/* double precision arguments %[eEfgG] */
661 	char softsign;		/* temporary negative sign for floats */
662 #endif
663 	char *dtoaresult;	/* buffer allocated by dtoa */
664 	int expt;		/* integer value of exponent */
665 	char expchar;		/* exponent character: [eEpP\0] */
666 	int expsize;		/* character count for expstr */
667 	int lead;		/* sig figs before decimal or group sep */
668 	int ndig;		/* actual number of digits returned by dtoa */
669 	CHAR_T expstr[MAXEXPDIG+2];	/* buffer for exponent string: e+ZZZ */
670 	int nseps;		/* number of group separators with ' */
671 	int nrepeats;		/* number of repeats of the last group */
672 #endif
673 	u_long	ulval;		/* integer arguments %[diouxX] */
674 	uintmax_t ujval;	/* %j, %ll, %q, %t, %z integers */
675 	int base;		/* base for [diouxX] conversion */
676 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
677 	int realsz;		/* field size expanded by dprec, sign, etc */
678 	int size;		/* size of converted field or string */
679 	int prsize;             /* max size of printed field */
680 	const char *xdigs;	/* digits for %[xX] conversion */
681 #ifdef NARROW
682 #define NIOV 8
683 	struct __siov *iovp;	/* for PRINT macro */
684 	struct __suio uio;	/* output information: summary */
685 	struct __siov iov[NIOV];/* ... and individual io vectors */
686 #else
687 	int n3;
688 #endif
689 	CHAR_T buf[BUF];	/* buffer with space for digits of uintmax_t */
690 	CHAR_T ox[2];		/* space for 0x hex-prefix */
691 	union arg *argtable;	/* args, built due to positional arg */
692 	union arg statargtable [STATIC_ARG_TBL_SIZE];
693 	int nextarg;		/* 1-based argument index */
694 	va_list orgap;		/* original argument pointer */
695 	CHAR_T *convbuf;	/* multibyte to wide conversion result */
696 
697 	/*
698 	 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
699 	 * fields occur frequently, increase PADSIZE and make the initialisers
700 	 * below longer.
701 	 */
702 #define	PADSIZE	16		/* pad chunk size */
703 	static CHAR_T blanks[PADSIZE] =
704 	 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
705 	static CHAR_T zeroes[PADSIZE] =
706 	 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
707 
708 	static const char xdigs_lower[16] = "0123456789abcdef";
709 	static const char xdigs_upper[16] = "0123456789ABCDEF";
710 
711 	/*
712 	 * BEWARE, these `goto error' on error, PRINT uses `n2' and
713 	 * PAD uses `n'.
714 	 */
715 #ifndef NARROW
716 #define	PRINT(ptr, len)	do {			\
717 	for (n3 = 0; n3 < (len); n3++)		\
718 		if (__xfputwc((ptr)[n3], fp, loc) == END_OF_FILE) { \
719 			fp->_flags |= __SERR;	\
720 			goto error;		\
721 		}				\
722 } while (0)
723 #define FLUSH()
724 #else
725 #define	PRINT(ptr, len) do { \
726 	iovp->iov_base = __UNCONST(ptr); \
727 	iovp->iov_len = (len); \
728 	uio.uio_resid += (len); \
729 	iovp++; \
730 	if (++uio.uio_iovcnt >= NIOV) { \
731 		if (__sprint(fp, &uio)) \
732 			goto error; \
733 		iovp = iov; \
734 	} \
735 } while (0)
736 #define	FLUSH() do { \
737 	if (uio.uio_resid && __sprint(fp, &uio)) \
738 		goto error; \
739 	uio.uio_iovcnt = 0; \
740 	iovp = iov; \
741 } while (0)
742 #endif /* NARROW */
743 
744 #define	PAD(howmany, with)	do {		\
745 	if ((n = (howmany)) > 0) {		\
746 		while (n > PADSIZE) {		\
747 			PRINT(with, PADSIZE);	\
748 			n -= PADSIZE;		\
749 		}				\
750 		PRINT(with, n);			\
751 	}					\
752 } while (0)
753 #define	PRINTANDPAD(p, ep, len, with) do {	\
754 	ptrdiff_t td = (ep) - (p);		\
755 	_DIAGASSERT(__type_fit(int, td));	\
756 	n2 = (int)td;       			\
757 	if (n2 > (len))				\
758 		n2 = (len);			\
759 	if (n2 > 0)				\
760 		PRINT((p), n2);			\
761 	PAD((len) - (n2 > 0 ? n2 : 0), (with));	\
762 } while (0)
763 
764 	/*
765 	 * Get the argument indexed by nextarg.   If the argument table is
766 	 * built, use it to get the argument.  If its not, get the next
767 	 * argument (and arguments must be gotten sequentially).
768 	 */
769 #define GETARG(type) \
770 	((/*CONSTCOND*/argtable != NULL) ? *((type*)(void*)(&argtable[nextarg++])) : \
771 	    (nextarg++, va_arg(ap, type)))
772 
773 	/*
774 	 * To extend shorts properly, we need both signed and unsigned
775 	 * argument extraction methods.
776 	 */
777 #define	SARG() \
778 	(flags&LONGINT ? GETARG(long) : \
779 	    flags&SHORTINT ? (long)(short)GETARG(int) : \
780 	    flags&CHARINT ? (long)(signed char)GETARG(int) : \
781 	    (long)GETARG(int))
782 #define	UARG() \
783 	(flags&LONGINT ? GETARG(u_long) : \
784 	    flags&SHORTINT ? (u_long)(u_short)GETARG(int) : \
785 	    flags&CHARINT ? (u_long)(u_char)GETARG(int) : \
786 	    (u_long)GETARG(u_int))
787 #define	INTMAX_SIZE	(INTMAXT|SIZET|PTRDIFFT|LLONGINT)
788 #define SJARG() \
789 	(flags&INTMAXT ? GETARG(intmax_t) : \
790 	    flags&SIZET ? (intmax_t)GETARG(ssize_t) : \
791 	    flags&PTRDIFFT ? (intmax_t)GETARG(ptrdiff_t) : \
792 	    (intmax_t)GETARG(long long))
793 #define	UJARG() \
794 	(flags&INTMAXT ? GETARG(uintmax_t) : \
795 	    flags&SIZET ? (uintmax_t)GETARG(size_t) : \
796 	    flags&PTRDIFFT ? (uintmax_t)GETARG(ptrdiff_t) : \
797 	    (uintmax_t)GETARG(unsigned long long))
798 
799 	/*
800 	 * Get * arguments, including the form *nn$.  Preserve the nextarg
801 	 * that the argument can be gotten once the type is determined.
802 	 */
803 #define GETASTER(val) \
804 	n2 = 0; \
805 	cp = fmt; \
806 	while (is_digit(*cp)) { \
807 		n2 = 10 * n2 + to_digit(*cp); \
808 		cp++; \
809 	} \
810 	if (*cp == '$') { \
811 		int hold = nextarg; \
812 		if (argtable == NULL) { \
813 			argtable = statargtable; \
814 			if (__find_arguments(fmt0, orgap, &argtable) == -1) \
815 				goto oomem; \
816 		} \
817 		nextarg = n2; \
818 		val = GETARG (int); \
819 		nextarg = hold; \
820 		fmt = ++cp; \
821 	} else { \
822 		val = GETARG (int); \
823 	}
824 
825 	_DIAGASSERT(fp != NULL);
826 	_DIAGASSERT(fmt0 != NULL);
827 
828 	_SET_ORIENTATION(fp, -1);
829 
830 	thousands_sep = '\0';
831 	grouping = NULL;
832 #ifndef NO_FLOATING_POINT
833 	decimal_point = localeconv_l(loc)->decimal_point;
834 	expsize = 0;		/* XXXGCC -Wuninitialized [sh3,m68000] */
835 	ndig = -1;	/* XXX gcc */
836 #endif
837 	convbuf = NULL;
838 	/* sorry, f{w,}printf(read_only_file, L"") returns {W,}EOF, not 0 */
839 	if (cantwrite(fp)) {
840 		errno = EBADF;
841 		return END_OF_FILE;
842 	}
843 
844 	/* optimise fprintf(stderr) (and other unbuffered Unix files) */
845 	if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
846 	    __sfileno(fp) != -1)
847 		return __sbprintf(fp, loc, fmt0, ap);
848 
849 	fmt = (CHAR_T *)__UNCONST(fmt0);
850 	argtable = NULL;
851 	nextarg = 1;
852 	va_copy(orgap, ap);
853 #ifdef NARROW
854 	uio.uio_iov = iovp = iov;
855 	uio.uio_resid = 0;
856 	uio.uio_iovcnt = 0;
857 #endif
858 	ret = 0;
859 
860 	/*
861 	 * Scan the format for conversions (`%' character).
862 	 */
863 	for (;;) {
864 		const CHAR_T *result;
865 
866 		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
867 			continue;
868 		_DIAGASSERT(__type_fit(int, fmt - cp));
869 		if ((n = (int)(fmt - cp)) != 0) {
870 			if ((unsigned)ret + n > INT_MAX) {
871 				ret = END_OF_FILE;
872 				goto error;
873 			}
874 			PRINT(cp, n);
875 			ret += n;
876 		}
877 		if (ch == '\0')
878 			goto done;
879 		fmt++;		/* skip over '%' */
880 
881 		flags = 0;
882 		dprec = 0;
883 		width = 0;
884 		prec = -1;
885 		sign = '\0';
886 		ox[1] = '\0';
887 #ifndef NO_FLOATING_POINT
888 		expchar = '\0';
889 		lead = 0;
890 		nseps = nrepeats = 0;
891 #endif
892 		ulval = 0;
893 		ujval = 0;
894 		xdigs = NULL;
895 
896 rflag:		ch = *fmt++;
897 reswitch:	switch (ch) {
898 		case ' ':
899 			/*-
900 			 * ``If the space and + flags both appear, the space
901 			 * flag will be ignored.''
902 			 *	-- ANSI X3J11
903 			 */
904 			if (!sign)
905 				sign = ' ';
906 			goto rflag;
907 		case '#':
908 			flags |= ALT;
909 			goto rflag;
910 		case '*':
911 			/*-
912 			 * ``A negative field width argument is taken as a
913 			 * - flag followed by a positive field width.''
914 			 *	-- ANSI X3J11
915 			 * They don't exclude field widths read from args.
916 			 */
917 			GETASTER (width);
918 			if (width >= 0)
919 				goto rflag;
920 			width = -width;
921 			/* FALLTHROUGH */
922 		case '-':
923 			flags |= LADJUST;
924 			goto rflag;
925 		case '+':
926 			sign = '+';
927 			goto rflag;
928 		case '\'':
929 			thousands_sep = *(localeconv_l(loc)->thousands_sep);
930 			grouping = localeconv_l(loc)->grouping;
931 			/* Use grouping if defined by locale */
932 			if (thousands_sep && grouping && *grouping)
933 				flags |= GROUPING;
934 			else {
935 				thousands_sep = '\0';
936 				grouping = NULL;
937 			}
938 			goto rflag;
939 		case '.':
940 			if ((ch = *fmt++) == '*') {
941 				GETASTER (prec);
942 				goto rflag;
943 			}
944 			prec = 0;
945 			while (is_digit(ch)) {
946 				prec = 10 * prec + to_digit(ch);
947 				ch = *fmt++;
948 			}
949 			goto reswitch;
950 		case '0':
951 			/*-
952 			 * ``Note that 0 is taken as a flag, not as the
953 			 * beginning of a field width.''
954 			 *	-- ANSI X3J11
955 			 */
956 			flags |= ZEROPAD;
957 			goto rflag;
958 		case '1': case '2': case '3': case '4':
959 		case '5': case '6': case '7': case '8': case '9':
960 			n = 0;
961 			do {
962 				n = 10 * n + to_digit(ch);
963 				ch = *fmt++;
964 			} while (is_digit(ch));
965 			if (ch == '$') {
966 				nextarg = n;
967 				if (argtable == NULL) {
968 					argtable = statargtable;
969 					if (__find_arguments(fmt0, orgap,
970 					    &argtable) == -1)
971 						goto oomem;
972 				}
973 				goto rflag;
974 			}
975 			width = n;
976 			goto reswitch;
977 #ifndef NO_FLOATING_POINT
978 		case 'L':
979 			flags |= LONGDBL;
980 			goto rflag;
981 #endif
982 		case 'h':
983 			if (flags & SHORTINT) {
984 				flags &= ~SHORTINT;
985 				flags |= CHARINT;
986 			} else
987 				flags |= SHORTINT;
988 			goto rflag;
989 		case 'j':
990 			flags |= INTMAXT;
991 			goto rflag;
992 		case 'l':
993 			if (flags & LONGINT) {
994 				flags &= ~LONGINT;
995 				flags |= LLONGINT;
996 			} else
997 				flags |= LONGINT;
998 			goto rflag;
999 		case 'q':
1000 			flags |= LLONGINT;	/* not necessarily */
1001 			goto rflag;
1002 		case 't':
1003 			flags |= PTRDIFFT;
1004 			goto rflag;
1005 		case 'z':
1006 			flags |= SIZET;
1007 			goto rflag;
1008 		case 'C':
1009 			flags |= LONGINT;
1010 			/*FALLTHROUGH*/
1011 		case 'c':
1012 #ifdef NARROW
1013 			if (flags & LONGINT) {
1014 				static const mbstate_t initial;
1015 				mbstate_t mbs;
1016 				size_t mbseqlen;
1017 
1018 				mbs = initial;
1019 				mbseqlen = wcrtomb_l(buf,
1020 				    (wchar_t)GETARG(wint_t), &mbs, loc);
1021 				if (mbseqlen == (size_t)-1) {
1022 					fp->_flags |= __SERR;
1023 					goto error;
1024 				}
1025 				size = (int)mbseqlen;
1026 			} else {
1027 				*buf = GETARG(int);
1028 				size = 1;
1029 			}
1030 #else
1031 			if (flags & LONGINT)
1032 				*buf = (wchar_t)GETARG(wint_t);
1033 			else
1034 				*buf = (wchar_t)btowc_l(GETARG(int), loc);
1035 			size = 1;
1036 #endif
1037 			result = buf;
1038 			sign = '\0';
1039 			break;
1040 		case 'D':
1041 			flags |= LONGINT;
1042 			/*FALLTHROUGH*/
1043 		case 'd':
1044 		case 'i':
1045 			if (flags & INTMAX_SIZE) {
1046 				ujval = SJARG();
1047 				if ((intmax_t)ujval < 0) {
1048 					ujval = -ujval;
1049 					sign = '-';
1050 				}
1051 			} else {
1052 				ulval = SARG();
1053 				if ((long)ulval < 0) {
1054 					ulval = -ulval;
1055 					sign = '-';
1056 				}
1057 			}
1058 			base = 10;
1059 			goto number;
1060 #ifndef NO_FLOATING_POINT
1061 #ifdef WIDE_DOUBLE
1062 		case 'a':
1063 		case 'A':
1064 			if (ch == 'a') {
1065 				ox[1] = 'x';
1066 				xdigs = xdigs_lower;
1067 				expchar = 'p';
1068 			} else {
1069 				ox[1] = 'X';
1070 				xdigs = xdigs_upper;
1071 				expchar = 'P';
1072 			}
1073 			if (prec >= 0)
1074 				prec++;
1075 			if (flags & LONGDBL) {
1076 				fparg.ldbl = GETARG(long double);
1077 				dtoaresult =
1078 				    __hldtoa(fparg.ldbl, xdigs, prec,
1079 				        &expt, &signflag, &dtoaend);
1080 			} else {
1081 				fparg.dbl = GETARG(double);
1082 				dtoaresult =
1083 				    __hdtoa(fparg.dbl, xdigs, prec,
1084 				        &expt, &signflag, &dtoaend);
1085 			}
1086 			if (dtoaresult == NULL)
1087 				goto oomem;
1088 
1089 			if (prec < 0) {
1090 				_DIAGASSERT(__type_fit(int,
1091 				    dtoaend - dtoaresult));
1092 				prec = (int)(dtoaend - dtoaresult);
1093 			}
1094 			if (expt == INT_MAX)
1095 				ox[1] = '\0';
1096 			_DIAGASSERT(__type_fit(int, dtoaend - dtoaresult));
1097 			ndig = (int)(dtoaend - dtoaresult);
1098 			if (convbuf != NULL)
1099 				free(convbuf);
1100 #ifndef NARROW
1101 			result = convbuf = __mbsconv(dtoaresult, -1, loc);
1102 #else
1103 			/*XXX inefficient*/
1104 			result = convbuf = strdup(dtoaresult);
1105 #endif
1106 			if (result == NULL)
1107 				goto oomem;
1108 			__freedtoa(dtoaresult);
1109 			goto fp_common;
1110 		case 'e':
1111 		case 'E':
1112 			expchar = ch;
1113 			if (prec < 0)	/* account for digit before decpt */
1114 				prec = DEFPREC + 1;
1115 			else
1116 				prec++;
1117 			goto fp_begin;
1118 		case 'f':
1119 		case 'F':
1120 			expchar = '\0';
1121 			goto fp_begin;
1122 		case 'g':
1123 		case 'G':
1124 			expchar = ch - ('g' - 'e');
1125 			if (prec == 0)
1126 				prec = 1;
1127 fp_begin:
1128 			if (prec < 0)
1129 				prec = DEFPREC;
1130 			if (flags & LONGDBL) {
1131 				fparg.ldbl = GETARG(long double);
1132 				dtoaresult =
1133 				    __ldtoa(&fparg.ldbl, expchar ? 2 : 3, prec,
1134 				    &expt, &signflag, &dtoaend);
1135 			} else {
1136 				fparg.dbl = GETARG(double);
1137 				dtoaresult =
1138 				    __dtoa(fparg.dbl, expchar ? 2 : 3, prec,
1139 				    &expt, &signflag, &dtoaend);
1140 				if (expt == 9999)
1141 					expt = INT_MAX;
1142 			}
1143 			if (dtoaresult == NULL)
1144 				goto oomem;
1145 			_DIAGASSERT(__type_fit(int, dtoaend - dtoaresult));
1146 			ndig = (int)(dtoaend - dtoaresult);
1147 			if (convbuf != NULL)
1148 				free(convbuf);
1149 #ifndef NARROW
1150 			result = convbuf = __mbsconv(dtoaresult, -1, loc);
1151 #else
1152 			/*XXX inefficient*/
1153 			result = convbuf = strdup(dtoaresult);
1154 #endif
1155 			if (result == NULL)
1156 				goto oomem;
1157 			__freedtoa(dtoaresult);
1158 fp_common:
1159 			if (signflag)
1160 				sign = '-';
1161 			if (expt == INT_MAX) {	/* inf or nan */
1162 				if (*result == 'N') {
1163 					result = (ch >= 'a') ? STRCONST("nan") :
1164 					    STRCONST("NAN");
1165 					sign = '\0';
1166 				} else
1167 					result = (ch >= 'a') ? STRCONST("inf") :
1168 					    STRCONST("INF");
1169 				size = 3;
1170 				flags &= ~ZEROPAD;
1171 				break;
1172 			}
1173 #else
1174 		case 'e':
1175 		case 'E':
1176 		case 'f':
1177 		case 'F':
1178 		case 'g':
1179 		case 'G':
1180 			if (prec == -1) {
1181 				prec = DEFPREC;
1182 			} else if ((ch == 'g' || ch == 'G') && prec == 0) {
1183 				prec = 1;
1184 			}
1185 
1186 			if (flags & LONGDBL) {
1187 				_double = (double) GETARG(long double);
1188 			} else {
1189 				_double = GETARG(double);
1190 			}
1191 
1192 			/* do this before tricky precision changes */
1193 			if (isinf(_double)) {
1194 				if (_double < 0)
1195 					sign = '-';
1196 				if (ch == 'E' || ch == 'F' || ch == 'G')
1197 					result = STRCONST("INF");
1198 				else
1199 					result = STRCONST("inf");
1200 				size = 3;
1201 				flags &= ~ZEROPAD;
1202 				break;
1203 			}
1204 			if (isnan(_double)) {
1205 				if (ch == 'E' || ch == 'F' || ch == 'G')
1206 					result = STRCONST("NAN");
1207 				else
1208 					result = STRCONST("nan");
1209 				size = 3;
1210 				flags &= ~ZEROPAD;
1211 				break;
1212 			}
1213 
1214 			flags |= FPT;
1215 			dtoaresult = cvt(_double, prec, flags, &softsign,
1216 			    &expt, ch, &ndig);
1217 			if (dtoaresult == NULL)
1218 				goto oomem;
1219 			if (convbuf != NULL)
1220 				free(convbuf);
1221 #ifndef NARROW
1222 			result = convbuf = __mbsconv(dtoaresult, -1, loc);
1223 #else
1224 			/*XXX inefficient*/
1225 			result = convbuf = strdup(dtoaresult);
1226 #endif
1227 			if (result == NULL)
1228 				goto oomem;
1229 			__freedtoa(dtoaresult);
1230 			if (softsign)
1231 				sign = '-';
1232 #endif
1233 			flags |= FPT;
1234 			if (ch == 'g' || ch == 'G') {
1235 				if (expt > -4 && expt <= prec) {
1236 					/* Make %[gG] smell like %[fF] */
1237 					expchar = '\0';
1238 					if (flags & ALT)
1239 						prec -= expt;
1240 					else
1241 						prec = ndig - expt;
1242 					if (prec < 0)
1243 						prec = 0;
1244 				} else {
1245 					/*
1246 					 * Make %[gG] smell like %[eE], but
1247 					 * trim trailing zeroes if no # flag.
1248 					 */
1249 					if (!(flags & ALT))
1250 						prec = ndig;
1251 				}
1252 			}
1253 			if (expchar) {
1254 				expsize = exponent(expstr, expt - 1, expchar);
1255 				size = expsize + prec;
1256 				if (prec > 1 || flags & ALT)
1257 					++size;
1258 			} else {
1259 				/* space for digits before decimal point */
1260 				if (expt > 0)
1261 					size = expt;
1262 				else	/* "0" */
1263 					size = 1;
1264 				/* space for decimal pt and following digits */
1265 				if (prec || flags & ALT)
1266 					size += prec + 1;
1267 				if (grouping && expt > 0) {
1268 					/* space for thousands' grouping */
1269 					nseps = nrepeats = 0;
1270 					lead = expt;
1271 					while ((unsigned char)*grouping
1272 					    != (unsigned char)CHAR_MAX) {
1273 						if (lead <= *grouping)
1274 							break;
1275 						lead -= *grouping;
1276 						if (*(grouping+1)) {
1277 							nseps++;
1278 							grouping++;
1279 						} else
1280 							nrepeats++;
1281 					}
1282 					size += nseps + nrepeats;
1283 				} else
1284 					lead = expt;
1285 			}
1286 			break;
1287 #endif /* !NO_FLOATING_POINT */
1288 		case 'n':
1289 			/*
1290 			 * Assignment-like behavior is specified if the
1291 			 * value overflows or is otherwise unrepresentable.
1292 			 * C99 says to use `signed char' for %hhn conversions.
1293 			 */
1294 			if (flags & LLONGINT)
1295 				*GETARG(long long *) = ret;
1296 			else if (flags & SIZET)
1297 				*GETARG(ssize_t *) = (ssize_t)ret;
1298 			else if (flags & PTRDIFFT)
1299 				*GETARG(ptrdiff_t *) = ret;
1300 			else if (flags & INTMAXT)
1301 				*GETARG(intmax_t *) = ret;
1302 			else if (flags & LONGINT)
1303 				*GETARG(long *) = ret;
1304 			else if (flags & SHORTINT)
1305 				*GETARG(short *) = ret;
1306 			else if (flags & CHARINT)
1307 				*GETARG(signed char *) = ret;
1308 			else
1309 				*GETARG(int *) = ret;
1310 			continue;	/* no output */
1311 		case 'O':
1312 			flags |= LONGINT;
1313 			/*FALLTHROUGH*/
1314 		case 'o':
1315 			if (flags & INTMAX_SIZE)
1316 				ujval = UJARG();
1317 			else
1318 				ulval = UARG();
1319 			base = 8;
1320 			goto nosign;
1321 		case 'p':
1322 			/*-
1323 			 * ``The argument shall be a pointer to void.  The
1324 			 * value of the pointer is converted to a sequence
1325 			 * of printable characters, in an implementation-
1326 			 * defined manner.''
1327 			 *	-- ANSI X3J11
1328 			 */
1329 			ujval = (uintmax_t)(uintptr_t)GETARG(void *);
1330 			base = 16;
1331 			xdigs = xdigs_lower;
1332 			flags = flags | INTMAXT;
1333 			ox[1] = 'x';
1334 			goto nosign;
1335 		case 'S':
1336 			flags |= LONGINT;
1337 			/*FALLTHROUGH*/
1338 		case 's':
1339 			if ((flags & LONGINT) != MULTI) {
1340 				if ((result = GETARG(CHAR_T *)) == NULL)
1341 					result = STRCONST("(null)");
1342 			} else {
1343 				MCHAR_T *mc;
1344 
1345 				if (convbuf != NULL)
1346 					free(convbuf);
1347 				if ((mc = GETARG(MCHAR_T *)) == NULL)
1348 					result = STRCONST("(null)");
1349 				else {
1350 					convbuf = SCONV(mc, prec, loc);
1351 					if (convbuf == NULL) {
1352 						fp->_flags |= __SERR;
1353 						goto error;
1354 					}
1355 					result = convbuf;
1356 				}
1357 			}
1358 
1359 			if (prec >= 0) {
1360 				/*
1361 				 * can't use STRLEN; can only look for the
1362 				 * NUL in the first `prec' characters, and
1363 				 * STRLEN() will go further.
1364 				 */
1365 				CHAR_T *p = MEMCHR(result, 0, (size_t)prec);
1366 
1367 				if (p != NULL) {
1368 					_DIAGASSERT(__type_fit(int,
1369 					    p - result));
1370 					size = (int)(p - result);
1371 					if (size > prec)
1372 						size = prec;
1373 				} else
1374 					size = prec;
1375 			} else {
1376 				size_t rlen = STRLEN(result);
1377 				_DIAGASSERT(__type_fit(int, rlen));
1378 				size = (int)rlen;
1379 			}
1380 			sign = '\0';
1381 			break;
1382 		case 'U':
1383 			flags |= LONGINT;
1384 			/*FALLTHROUGH*/
1385 		case 'u':
1386 			if (flags & INTMAX_SIZE)
1387 				ujval = UJARG();
1388 			else
1389 				ulval = UARG();
1390 			base = 10;
1391 			goto nosign;
1392 		case 'X':
1393 			xdigs = xdigs_upper;
1394 			goto hex;
1395 		case 'x':
1396 			xdigs = xdigs_lower;
1397 hex:
1398 			if (flags & INTMAX_SIZE)
1399 				ujval = UJARG();
1400 			else
1401 				ulval = UARG();
1402 			base = 16;
1403 			/* leading 0x/X only if non-zero */
1404 			if (flags & ALT &&
1405 			    (flags & INTMAX_SIZE ? ujval != 0 : ulval != 0))
1406 				ox[1] = ch;
1407 
1408 			flags &= ~GROUPING;
1409 			/* unsigned conversions */
1410 nosign:			sign = '\0';
1411 			/*-
1412 			 * ``... diouXx conversions ... if a precision is
1413 			 * specified, the 0 flag will be ignored.''
1414 			 *	-- ANSI X3J11
1415 			 */
1416 number:			if ((dprec = prec) >= 0)
1417 				flags &= ~ZEROPAD;
1418 
1419 			/*-
1420 			 * ``The result of converting a zero value with an
1421 			 * explicit precision of zero is no characters.''
1422 			 *	-- ANSI X3J11
1423 			 *
1424 			 * ``The C Standard is clear enough as is.  The call
1425 			 * printf("%#.0o", 0) should print 0.''
1426 			 *	-- Defect Report #151
1427 			 */
1428 			result = cp = buf + BUF;
1429 			if (flags & INTMAX_SIZE) {
1430 				if (ujval != 0 || prec != 0 ||
1431 				    (flags & ALT && base == 8))
1432 					result = __ujtoa(ujval, cp, base,
1433 					    flags & ALT, xdigs,
1434 					    flags & GROUPING, thousands_sep,
1435 					    grouping);
1436 			} else {
1437 				if (ulval != 0 || prec != 0 ||
1438 				    (flags & ALT && base == 8))
1439 					result = __ultoa(ulval, cp, base,
1440 					    flags & ALT, xdigs,
1441 					    flags & GROUPING, thousands_sep,
1442 					    grouping);
1443 			}
1444 			_DIAGASSERT(__type_fit(int, buf + BUF - result));
1445 			size = (int)(buf + BUF - result);
1446 			if (size > BUF)	/* should never happen */
1447 				abort();
1448 			break;
1449 		default:	/* "%?" prints ?, unless ? is NUL */
1450 			if (ch == '\0')
1451 				goto done;
1452 			/* pretend it was %c with argument ch */
1453 			*buf = ch;
1454 			result = buf;
1455 			size = 1;
1456 			sign = '\0';
1457 			break;
1458 		}
1459 
1460 		/*
1461 		 * All reasonable formats wind up here.  At this point, `result'
1462 		 * points to a string which (if not flags&LADJUST) should be
1463 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1464 		 * first be prefixed by any sign or other prefix; otherwise,
1465 		 * it should be blank padded before the prefix is emitted.
1466 		 * After any left-hand padding and prefixing, emit zeroes
1467 		 * required by a decimal [diouxX] precision, then print the
1468 		 * string proper, then emit zeroes required by any leftover
1469 		 * floating precision; finally, if LADJUST, pad with blanks.
1470 		 *
1471 		 * Compute actual size, so we know how much to pad.
1472 		 * size excludes decimal prec; realsz includes it.
1473 		 */
1474 		realsz = dprec > size ? dprec : size;
1475 		if (sign)
1476 			realsz++;
1477 		if (ox[1])
1478 			realsz += 2;
1479 
1480 		prsize = width > realsz ? width : realsz;
1481 		if ((unsigned)ret + prsize > INT_MAX) {
1482 			ret = END_OF_FILE;
1483 			goto error;
1484 		}
1485 
1486 		/* right-adjusting blank padding */
1487 		if ((flags & (LADJUST|ZEROPAD)) == 0)
1488 			PAD(width - realsz, blanks);
1489 
1490 		/* prefix */
1491 		if (sign)
1492 			PRINT(&sign, 1);
1493 
1494 		if (ox[1]) {	/* ox[1] is either x, X, or \0 */
1495 			ox[0] = '0';
1496 			PRINT(ox, 2);
1497 		}
1498 
1499 		/* right-adjusting zero padding */
1500 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
1501 			PAD(width - realsz, zeroes);
1502 
1503 		/* leading zeroes from decimal precision */
1504 		PAD(dprec - size, zeroes);
1505 
1506 		/* the string or number proper */
1507 #ifndef NO_FLOATING_POINT
1508 		if ((flags & FPT) == 0) {
1509 			PRINT(result, size);
1510 		} else {	/* glue together f_p fragments */
1511 			if (!expchar) {	/* %[fF] or sufficiently short %[gG] */
1512 				if (expt <= 0) {
1513 					PRINT(zeroes, 1);
1514 					if (prec || flags & ALT)
1515 						PRINT(decimal_point, 1);
1516 					PAD(-expt, zeroes);
1517 					/* already handled initial 0's */
1518 					prec += expt;
1519 				} else {
1520 					PRINTANDPAD(result, convbuf + ndig,
1521 					    lead, zeroes);
1522 					result += lead;
1523 					if (grouping) {
1524 						while (nseps>0 || nrepeats>0) {
1525 							if (nrepeats > 0)
1526 								nrepeats--;
1527 							else {
1528 								grouping--;
1529 								nseps--;
1530 							}
1531 							PRINT(&thousands_sep,
1532 							    1);
1533 							PRINTANDPAD(result,
1534 							    convbuf + ndig,
1535 							    *grouping, zeroes);
1536 							result += *grouping;
1537 						}
1538 						if (result > convbuf + ndig)
1539 							result = convbuf + ndig;
1540 					}
1541 					if (prec || flags & ALT) {
1542 						buf[0] = *decimal_point;
1543 						PRINT(buf, 1);
1544 					}
1545 				}
1546 				PRINTANDPAD(result, convbuf + ndig, prec,
1547 				    zeroes);
1548 			} else {	/* %[eE] or sufficiently long %[gG] */
1549 				if (prec > 1 || flags & ALT) {
1550 					buf[0] = *result++;
1551 					buf[1] = *decimal_point;
1552 					PRINT(buf, 2);
1553 					PRINT(result, ndig-1);
1554 					PAD(prec - ndig, zeroes);
1555 				} else	/* XeYYY */
1556 					PRINT(result, 1);
1557 				PRINT(expstr, expsize);
1558 			}
1559 		}
1560 #else
1561 		PRINT(result, size);
1562 #endif
1563 		/* left-adjusting padding (always blank) */
1564 		if (flags & LADJUST)
1565 			PAD(width - realsz, blanks);
1566 
1567 		/* finally, adjust ret */
1568 		ret += prsize;
1569 		FLUSH();
1570 	}
1571 done:
1572 	FLUSH();
1573 error:
1574 	va_end(orgap);
1575 	if (convbuf != NULL)
1576 		free(convbuf);
1577 	if (__sferror(fp))
1578 		ret = END_OF_FILE;
1579 	if ((argtable != NULL) && (argtable != statargtable))
1580 		free (argtable);
1581 	return ret;
1582 	/* NOTREACHED */
1583 oomem:
1584 	errno = ENOMEM;
1585 	ret = END_OF_FILE;
1586 	goto error;
1587 }
1588 
1589 /*
1590  * Find all arguments when a positional parameter is encountered.  Returns a
1591  * table, indexed by argument number, of pointers to each arguments.  The
1592  * initial argument table should be an array of STATIC_ARG_TBL_SIZE entries.
1593  * It will be replaces with a malloc-ed one if it overflows.
1594  */
1595 static int
1596 __find_arguments(const CHAR_T *fmt0, va_list ap, union arg **argtable)
1597 {
1598 	CHAR_T *fmt;		/* format string */
1599 	int ch;			/* character from fmt */
1600 	size_t n, n2;		/* handy index (short term usage) */
1601 	CHAR_T *cp;		/* handy char pointer (short term usage) */
1602 	int flags;		/* flags as above */
1603 	enum typeid *typetable; /* table of types */
1604 	enum typeid stattypetable [STATIC_ARG_TBL_SIZE];
1605 	size_t tablesize;	/* current size of type table */
1606 	size_t tablemax;	/* largest used index in table */
1607 	size_t nextarg;		/* 1-based argument index */
1608 	size_t nitems;		/* number of items we picked from the stack */
1609 
1610 	/*
1611 	 * Add an argument type to the table, expanding if necessary.
1612 	 * Check for overflow.
1613 	 */
1614 #define ADDTYPE(type) \
1615 	do { \
1616 		if (nextarg > SIZE_MAX / sizeof(**argtable)) { \
1617 			if (typetable != stattypetable) \
1618 				free(typetable); \
1619 			return -1; \
1620 		} \
1621 		if (nextarg >= tablesize) \
1622 			if (__grow_type_table(nextarg, &typetable, \
1623 			    &tablesize) == -1) \
1624 				return -1; \
1625 		if (nextarg > tablemax) \
1626 			tablemax = nextarg; \
1627 		typetable[nextarg++] = type; \
1628 		nitems++; \
1629 	} while (0)
1630 
1631 #define	ADDSARG() \
1632 	do { \
1633 		if (flags & INTMAXT)  \
1634 			ADDTYPE(T_INTMAXT); \
1635 		else if (flags & SIZET)  \
1636 			ADDTYPE(T_SSIZET); \
1637 		else if (flags & PTRDIFFT) \
1638 			ADDTYPE(T_PTRDIFFT); \
1639 		else if (flags & LLONGINT) \
1640 			ADDTYPE(T_LLONG); \
1641 		else if (flags & LONGINT) \
1642 			ADDTYPE(T_LONG); \
1643 		else \
1644 			ADDTYPE(T_INT); \
1645 	} while (0)
1646 
1647 #define	ADDUARG() \
1648 	do { \
1649 		if (flags & INTMAXT)  \
1650 			ADDTYPE(T_UINTMAXT); \
1651 		else if (flags & SIZET)  \
1652 			ADDTYPE(T_SIZET); \
1653 		else if (flags & PTRDIFFT) \
1654 			ADDTYPE(T_PTRDIFFT); \
1655 		else if (flags & LLONGINT) \
1656 			ADDTYPE(T_U_LLONG); \
1657 		else if (flags & LONGINT) \
1658 			ADDTYPE(T_U_LONG); \
1659 		else \
1660 			ADDTYPE(T_U_INT); \
1661 	} while (0)
1662 	/*
1663 	 * Add * arguments to the type array.
1664 	 */
1665 #define ADDASTER() \
1666 	n2 = 0; \
1667 	cp = fmt; \
1668 	while (is_digit(*cp)) { \
1669 		n2 = 10 * n2 + to_digit(*cp); \
1670 		cp++; \
1671 	} \
1672 	if (*cp == '$') { \
1673 		size_t hold = nextarg; \
1674 		nextarg = n2; \
1675 		ADDTYPE(T_INT); \
1676 		nextarg = hold; \
1677 		fmt = ++cp; \
1678 	} else { \
1679 		ADDTYPE(T_INT); \
1680 	}
1681 	fmt = (CHAR_T *)__UNCONST(fmt0);
1682 	memset(stattypetable, 0, sizeof(stattypetable));
1683 	typetable = stattypetable;
1684 	tablesize = STATIC_ARG_TBL_SIZE;
1685 	tablemax = 0;
1686 	nextarg = 1;
1687 	nitems = 1;
1688 
1689 	/*
1690 	 * Scan the format for conversions (`%' character).
1691 	 */
1692 	for (;;) {
1693 		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
1694 			/* void */;
1695 		if (ch == '\0')
1696 			goto done;
1697 		fmt++;		/* skip over '%' */
1698 
1699 		flags = 0;
1700 
1701 rflag:		ch = *fmt++;
1702 reswitch:	switch (ch) {
1703 		case ' ':
1704 		case '#':
1705 			goto rflag;
1706 		case '*':
1707 			ADDASTER ();
1708 			goto rflag;
1709 		case '-':
1710 		case '+':
1711 		case '\'':
1712 			goto rflag;
1713 		case '.':
1714 			if ((ch = *fmt++) == '*') {
1715 				ADDASTER ();
1716 				goto rflag;
1717 			}
1718 			while (is_digit(ch)) {
1719 				ch = *fmt++;
1720 			}
1721 			goto reswitch;
1722 		case '0':
1723 			goto rflag;
1724 		case '1': case '2': case '3': case '4':
1725 		case '5': case '6': case '7': case '8': case '9':
1726 			n = 0;
1727 			do {
1728 				n = 10 * n + to_digit(ch);
1729 				ch = *fmt++;
1730 			} while (is_digit(ch));
1731 			if (ch == '$') {
1732 				nextarg = n;
1733 				goto rflag;
1734 			}
1735 			goto reswitch;
1736 #ifndef NO_FLOATING_POINT
1737 		case 'L':
1738 			flags |= LONGDBL;
1739 			goto rflag;
1740 #endif
1741 		case 'h':
1742 			if (flags & SHORTINT) {
1743 				flags &= ~SHORTINT;
1744 				flags |= CHARINT;
1745 			} else
1746 				flags |= SHORTINT;
1747 			goto rflag;
1748 		case 'j':
1749 			flags |= INTMAXT;
1750 			goto rflag;
1751 		case 'l':
1752 			if (flags & LONGINT) {
1753 				flags &= ~LONGINT;
1754 				flags |= LLONGINT;
1755 			} else
1756 				flags |= LONGINT;
1757 			goto rflag;
1758 		case 'q':
1759 			flags |= LLONGINT;	/* not necessarily */
1760 			goto rflag;
1761 		case 't':
1762 			flags |= PTRDIFFT;
1763 			goto rflag;
1764 		case 'z':
1765 			flags |= SIZET;
1766 			goto rflag;
1767 		case 'C':
1768 			flags |= LONGINT;
1769 			/*FALLTHROUGH*/
1770 		case 'c':
1771 			if (flags & LONGINT)
1772 				ADDTYPE(T_WINT);
1773 			else
1774 				ADDTYPE(T_INT);
1775 			break;
1776 		case 'D':
1777 			flags |= LONGINT;
1778 			/*FALLTHROUGH*/
1779 		case 'd':
1780 		case 'i':
1781 			ADDSARG();
1782 			break;
1783 #ifndef NO_FLOATING_POINT
1784 		case 'a':
1785 		case 'A':
1786 		case 'e':
1787 		case 'E':
1788 		case 'f':
1789 		case 'g':
1790 		case 'G':
1791 			if (flags & LONGDBL)
1792 				ADDTYPE(T_LONG_DOUBLE);
1793 			else
1794 				ADDTYPE(T_DOUBLE);
1795 			break;
1796 #endif /* !NO_FLOATING_POINT */
1797 		case 'n':
1798 			if (flags & INTMAXT)
1799 				ADDTYPE(TP_INTMAXT);
1800 			else if (flags & PTRDIFFT)
1801 				ADDTYPE(TP_PTRDIFFT);
1802 			else if (flags & SIZET)
1803 				ADDTYPE(TP_SIZET);
1804 			else if (flags & LLONGINT)
1805 				ADDTYPE(TP_LLONG);
1806 			else if (flags & LONGINT)
1807 				ADDTYPE(TP_LONG);
1808 			else if (flags & SHORTINT)
1809 				ADDTYPE(TP_SHORT);
1810 			else if (flags & CHARINT)
1811 				ADDTYPE(TP_SCHAR);
1812 			else
1813 				ADDTYPE(TP_INT);
1814 			continue;	/* no output */
1815 		case 'O':
1816 			flags |= LONGINT;
1817 			/*FALLTHROUGH*/
1818 		case 'o':
1819 			ADDUARG();
1820 			break;
1821 		case 'p':
1822 			ADDTYPE(TP_VOID);
1823 			break;
1824 		case 'S':
1825 			flags |= LONGINT;
1826 			/*FALLTHROUGH*/
1827 		case 's':
1828 			if (flags & LONGINT)
1829 				ADDTYPE(TP_WCHAR);
1830 			else
1831 				ADDTYPE(TP_CHAR);
1832 			break;
1833 		case 'U':
1834 			flags |= LONGINT;
1835 			/*FALLTHROUGH*/
1836 		case 'u':
1837 		case 'X':
1838 		case 'x':
1839 			ADDUARG();
1840 			break;
1841 		default:	/* "%?" prints ?, unless ? is NUL */
1842 			if (ch == '\0')
1843 				goto done;
1844 			break;
1845 		}
1846 	}
1847 done:
1848 	/*
1849 	 * nitems contains the number of arguments we picked from the stack.
1850 	 * If tablemax is larger, this means that some positional argument,
1851 	 * tried to pick an argument the number of arguments possibly supplied.
1852 	 * Since positional arguments are typically used to swap the order of
1853 	 * the printf arguments and not to pick random arguments from strange
1854 	 * positions in the stack, we assume that if the positional argument
1855 	 * is trying to pick beyond the end of arguments, then this is wrong.
1856 	 * Alternatively we could find a way to figure out when va_arg() runs
1857 	 * out, but how to do that?
1858 	 */
1859 	if (nitems < tablemax) {
1860 		if (typetable != stattypetable)
1861 			free(typetable);
1862 		return -1;
1863 	}
1864 	/*
1865 	 * Build the argument table.
1866 	 */
1867 	if (tablemax >= STATIC_ARG_TBL_SIZE) {
1868 		*argtable = malloc(sizeof(**argtable) * (tablemax + 1));
1869 		if (*argtable == NULL) {
1870 			free(typetable);
1871 			return -1;
1872 		}
1873 	}
1874 
1875 	(*argtable) [0].intarg = 0;
1876 	for (n = 1; n <= tablemax; n++) {
1877 		switch (typetable [n]) {
1878 		    case T_UNUSED: /* whoops! */
1879 			(*argtable) [n].intarg = va_arg (ap, int);
1880 			break;
1881 		    case TP_SCHAR:
1882 			(*argtable) [n].pschararg = va_arg (ap, signed char *);
1883 			break;
1884 		    case TP_SHORT:
1885 			(*argtable) [n].pshortarg = va_arg (ap, short *);
1886 			break;
1887 		    case T_INT:
1888 			(*argtable) [n].intarg = va_arg (ap, int);
1889 			break;
1890 		    case T_U_INT:
1891 			(*argtable) [n].uintarg = va_arg (ap, unsigned int);
1892 			break;
1893 		    case TP_INT:
1894 			(*argtable) [n].pintarg = va_arg (ap, int *);
1895 			break;
1896 		    case T_LONG:
1897 			(*argtable) [n].longarg = va_arg (ap, long);
1898 			break;
1899 		    case T_U_LONG:
1900 			(*argtable) [n].ulongarg = va_arg (ap, unsigned long);
1901 			break;
1902 		    case TP_LONG:
1903 			(*argtable) [n].plongarg = va_arg (ap, long *);
1904 			break;
1905 		    case T_LLONG:
1906 			(*argtable) [n].longlongarg = va_arg (ap, long long);
1907 			break;
1908 		    case T_U_LLONG:
1909 			(*argtable) [n].ulonglongarg = va_arg (ap, unsigned long long);
1910 			break;
1911 		    case TP_LLONG:
1912 			(*argtable) [n].plonglongarg = va_arg (ap, long long *);
1913 			break;
1914 		    case T_PTRDIFFT:
1915 			(*argtable) [n].ptrdiffarg = va_arg (ap, ptrdiff_t);
1916 			break;
1917 		    case TP_PTRDIFFT:
1918 			(*argtable) [n].pptrdiffarg = va_arg (ap, ptrdiff_t *);
1919 			break;
1920 		    case T_SSIZET:
1921 			(*argtable) [n].ssizearg = va_arg (ap, ssize_t);
1922 			break;
1923 		    case T_SIZET:
1924 			(*argtable) [n].sizearg = va_arg (ap, size_t);
1925 			break;
1926 		    case TP_SIZET:
1927 			(*argtable) [n].psizearg = va_arg (ap, size_t *);
1928 			break;
1929 		    case T_INTMAXT:
1930 			(*argtable) [n].intmaxarg = va_arg (ap, intmax_t);
1931 			break;
1932 		    case T_UINTMAXT:
1933 			(*argtable) [n].uintmaxarg = va_arg (ap, uintmax_t);
1934 			break;
1935 		    case TP_INTMAXT:
1936 			(*argtable) [n].pintmaxarg = va_arg (ap, intmax_t *);
1937 			break;
1938 		    case T_DOUBLE:
1939 #ifndef NO_FLOATING_POINT
1940 			(*argtable) [n].doublearg = va_arg (ap, double);
1941 #endif
1942 			break;
1943 		    case T_LONG_DOUBLE:
1944 #ifndef NO_FLOATING_POINT
1945 			(*argtable) [n].longdoublearg = va_arg (ap, long double);
1946 #endif
1947 			break;
1948 		    case TP_CHAR:
1949 			(*argtable) [n].pchararg = va_arg (ap, char *);
1950 			break;
1951 		    case TP_VOID:
1952 			(*argtable) [n].pvoidarg = va_arg (ap, void *);
1953 			break;
1954 		    case T_WINT:
1955 			(*argtable) [n].wintarg = va_arg (ap, wint_t);
1956 			break;
1957 		    case TP_WCHAR:
1958 			(*argtable) [n].pwchararg = va_arg (ap, wchar_t *);
1959 			break;
1960 		}
1961 	}
1962 
1963 	if (typetable != stattypetable)
1964 		free (typetable);
1965 	return 0;
1966 }
1967 
1968 /*
1969  * Increase the size of the type table.
1970  */
1971 static int
1972 __grow_type_table (size_t nextarg, enum typeid **typetable, size_t *tablesize)
1973 {
1974 	enum typeid *const oldtable = *typetable;
1975 	const size_t oldsize = *tablesize;
1976 	enum typeid *newtable;
1977 	size_t newsize = oldsize * 2;
1978 
1979 	if (newsize < nextarg + 1)
1980 		newsize = nextarg + 1;
1981 	if (oldsize == STATIC_ARG_TBL_SIZE) {
1982 		newtable = NULL;
1983 		errno = reallocarr(&newtable, newsize, sizeof(*newtable));
1984 		if (errno)
1985 			return -1;
1986 		memcpy(newtable, oldtable, oldsize * sizeof(*newtable));
1987 	} else {
1988 		newtable = oldtable;
1989 		errno = reallocarr(&newtable, newsize, sizeof(*newtable));
1990 		if (errno) {
1991 			int serrno = errno;
1992 			free(oldtable);
1993 			errno = serrno;
1994 			return -1;
1995 		}
1996 	}
1997 	memset(&newtable[oldsize], 0, (newsize - oldsize) * sizeof(*newtable));
1998 
1999 	*typetable = newtable;
2000 	*tablesize = newsize;
2001 	return 0;
2002 }
2003 
2004 
2005 #ifndef NO_FLOATING_POINT
2006 #ifndef WIDE_DOUBLE
2007 static char *
2008 cvt(double value, int ndigits, int flags, char *sign, int *decpt, int ch,
2009     int *length)
2010 {
2011 	int mode, dsgn;
2012 	char *digits, *bp, *rve;
2013 
2014 	_DIAGASSERT(decpt != NULL);
2015 	_DIAGASSERT(length != NULL);
2016 	_DIAGASSERT(sign != NULL);
2017 
2018 	if (ch == 'f') {
2019 		mode = 3;		/* ndigits after the decimal point */
2020 	} else {
2021 		/* To obtain ndigits after the decimal point for the 'e'
2022 		 * and 'E' formats, round to ndigits + 1 significant
2023 		 * figures.
2024 		 */
2025 		if (ch == 'e' || ch == 'E') {
2026 			ndigits++;
2027 		}
2028 		mode = 2;		/* ndigits significant digits */
2029 	}
2030 
2031 	digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
2032 	if (digits == NULL)
2033 		return NULL;
2034 	if (dsgn) {
2035 		value = -value;
2036 		*sign = '-';
2037 	} else
2038 		*sign = '\000';
2039 	if ((ch != 'g' && ch != 'G') || flags & ALT) {	/* Print trailing zeros */
2040 		bp = digits + ndigits;
2041 		if (ch == 'f') {
2042 			if (*digits == '0' && value)
2043 				*decpt = -ndigits + 1;
2044 			bp += *decpt;
2045 		}
2046 		if (value == 0)	/* kludge for __dtoa irregularity */
2047 			rve = bp;
2048 		while (rve < bp)
2049 			*rve++ = '0';
2050 	}
2051 	*length = rve - digits;
2052 	return digits;
2053 }
2054 #endif
2055 
2056 static int
2057 exponent(CHAR_T *p0, int expo, int fmtch)
2058 {
2059 	CHAR_T *p, *t;
2060 	CHAR_T expbuf[MAXEXPDIG];
2061 
2062 	p = p0;
2063 	*p++ = fmtch;
2064 	if (expo < 0) {
2065 		expo = -expo;
2066 		*p++ = '-';
2067 	}
2068 	else
2069 		*p++ = '+';
2070 	t = expbuf + MAXEXPDIG;
2071 	if (expo > 9) {
2072 		do {
2073 			*--t = to_char(expo % 10);
2074 		} while ((expo /= 10) > 9);
2075 		*--t = to_char(expo);
2076 		for (; t < expbuf + MAXEXPDIG; *p++ = *t++);
2077 	}
2078 	else {
2079 		/*
2080 		 * Exponents for decimal floating point conversions
2081 		 * (%[eEgG]) must be at least two characters long,
2082 		 * whereas exponents for hexadecimal conversions can
2083 		 * be only one character long.
2084 		 */
2085 		if (fmtch == 'e' || fmtch == 'E')
2086 			*p++ = '0';
2087 		*p++ = to_char(expo);
2088 	}
2089 	_DIAGASSERT(__type_fit(int, p - p0));
2090 	return (int)(p - p0);
2091 }
2092 #endif /* !NO_FLOATING_POINT */
2093