xref: /freebsd/lib/libc/stdio/vfprintf.c (revision 7ef62cebc2f965b0f640263e179276928885e33d)
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  *
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 defined(LIBC_SCCS) && !defined(lint)
41 static char sccsid[] = "@(#)vfprintf.c	8.1 (Berkeley) 6/4/93";
42 #endif /* LIBC_SCCS and not lint */
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 /*
47  * Actual printf innards.
48  *
49  * This code is large and complicated...
50  */
51 
52 #include "namespace.h"
53 #include <sys/types.h>
54 
55 #include <ctype.h>
56 #include <errno.h>
57 #include <limits.h>
58 #include <locale.h>
59 #include <stddef.h>
60 #include <stdint.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <wchar.h>
65 #include <printf.h>
66 
67 #include <stdarg.h>
68 #include "xlocale_private.h"
69 #include "un-namespace.h"
70 
71 #include "libc_private.h"
72 #include "local.h"
73 #include "fvwrite.h"
74 #include "printflocal.h"
75 
76 static int	__sprint(FILE *, struct __suio *, locale_t);
77 static int	__sbprintf(FILE *, locale_t, const char *, va_list) __printflike(3, 0)
78 	__noinline;
79 static char	*__wcsconv(wchar_t *, int);
80 
81 #define	CHAR	char
82 #include "printfcommon.h"
83 
84 struct grouping_state {
85 	char *thousands_sep;	/* locale-specific thousands separator */
86 	int thousep_len;	/* length of thousands_sep */
87 	const char *grouping;	/* locale-specific numeric grouping rules */
88 	int lead;		/* sig figs before decimal or group sep */
89 	int nseps;		/* number of group separators with ' */
90 	int nrepeats;		/* number of repeats of the last group */
91 };
92 
93 /*
94  * Initialize the thousands' grouping state in preparation to print a
95  * number with ndigits digits. This routine returns the total number
96  * of bytes that will be needed.
97  */
98 static int
99 grouping_init(struct grouping_state *gs, int ndigits, locale_t loc)
100 {
101 	struct lconv *locale;
102 
103 	locale = localeconv_l(loc);
104 	gs->grouping = locale->grouping;
105 	gs->thousands_sep = locale->thousands_sep;
106 	gs->thousep_len = strlen(gs->thousands_sep);
107 
108 	gs->nseps = gs->nrepeats = 0;
109 	gs->lead = ndigits;
110 	while (*gs->grouping != CHAR_MAX) {
111 		if (gs->lead <= *gs->grouping)
112 			break;
113 		gs->lead -= *gs->grouping;
114 		if (*(gs->grouping+1)) {
115 			gs->nseps++;
116 			gs->grouping++;
117 		} else
118 			gs->nrepeats++;
119 	}
120 	return ((gs->nseps + gs->nrepeats) * gs->thousep_len);
121 }
122 
123 /*
124  * Print a number with thousands' separators.
125  */
126 static int
127 grouping_print(struct grouping_state *gs, struct io_state *iop,
128 	       const CHAR *cp, const CHAR *ep, locale_t locale)
129 {
130 	const CHAR *cp0 = cp;
131 
132 	if (io_printandpad(iop, cp, ep, gs->lead, zeroes, locale))
133 		return (-1);
134 	cp += gs->lead;
135 	while (gs->nseps > 0 || gs->nrepeats > 0) {
136 		if (gs->nrepeats > 0)
137 			gs->nrepeats--;
138 		else {
139 			gs->grouping--;
140 			gs->nseps--;
141 		}
142 		if (io_print(iop, gs->thousands_sep, gs->thousep_len, locale))
143 			return (-1);
144 		if (io_printandpad(iop, cp, ep, *gs->grouping, zeroes, locale))
145 			return (-1);
146 		cp += *gs->grouping;
147 	}
148 	if (cp > ep)
149 		cp = ep;
150 	return (cp - cp0);
151 }
152 
153 /*
154  * Flush out all the vectors defined by the given uio,
155  * then reset it so that it can be reused.
156  */
157 static int
158 __sprint(FILE *fp, struct __suio *uio, locale_t locale)
159 {
160 	int err;
161 
162 	if (uio->uio_resid == 0) {
163 		uio->uio_iovcnt = 0;
164 		return (0);
165 	}
166 	err = __sfvwrite(fp, uio);
167 	uio->uio_resid = 0;
168 	uio->uio_iovcnt = 0;
169 	return (err);
170 }
171 
172 /*
173  * Helper function for `fprintf to unbuffered unix file': creates a
174  * temporary buffer.  We only work on write-only files; this avoids
175  * worries about ungetc buffers and so forth.
176  */
177 static int
178 __sbprintf(FILE *fp, locale_t locale, const char *fmt, va_list ap)
179 {
180 	int ret;
181 	FILE fake = FAKE_FILE;
182 	unsigned char buf[BUFSIZ];
183 
184 	/* XXX This is probably not needed. */
185 	if (prepwrite(fp) != 0)
186 		return (EOF);
187 
188 	/* copy the important variables */
189 	fake._flags = fp->_flags & ~__SNBF;
190 	fake._file = fp->_file;
191 	fake._cookie = fp->_cookie;
192 	fake._write = fp->_write;
193 	fake._orientation = fp->_orientation;
194 	fake._mbstate = fp->_mbstate;
195 
196 	/* set up the buffer */
197 	fake._bf._base = fake._p = buf;
198 	fake._bf._size = fake._w = sizeof(buf);
199 	fake._lbfsize = 0;	/* not actually used, but Just In Case */
200 
201 	/* do the work, then copy any error status */
202 	ret = __vfprintf(&fake, locale, fmt, ap);
203 	if (ret >= 0 && __fflush(&fake))
204 		ret = EOF;
205 	if (fake._flags & __SERR)
206 		fp->_flags |= __SERR;
207 	return (ret);
208 }
209 
210 /*
211  * Convert a wide character string argument for the %ls format to a multibyte
212  * string representation. If not -1, prec specifies the maximum number of
213  * bytes to output, and also means that we can't assume that the wide char.
214  * string ends is null-terminated.
215  */
216 static char *
217 __wcsconv(wchar_t *wcsarg, int prec)
218 {
219 	static const mbstate_t initial;
220 	mbstate_t mbs;
221 	char buf[MB_LEN_MAX];
222 	wchar_t *p;
223 	char *convbuf;
224 	size_t clen, nbytes;
225 
226 	/* Allocate space for the maximum number of bytes we could output. */
227 	if (prec < 0) {
228 		p = wcsarg;
229 		mbs = initial;
230 		nbytes = wcsrtombs(NULL, (const wchar_t **)&p, 0, &mbs);
231 		if (nbytes == (size_t)-1)
232 			return (NULL);
233 	} else {
234 		/*
235 		 * Optimisation: if the output precision is small enough,
236 		 * just allocate enough memory for the maximum instead of
237 		 * scanning the string.
238 		 */
239 		if (prec < 128)
240 			nbytes = prec;
241 		else {
242 			nbytes = 0;
243 			p = wcsarg;
244 			mbs = initial;
245 			for (;;) {
246 				clen = wcrtomb(buf, *p++, &mbs);
247 				if (clen == 0 || clen == (size_t)-1 ||
248 				    nbytes + clen > prec)
249 					break;
250 				nbytes += clen;
251 			}
252 		}
253 	}
254 	if ((convbuf = malloc(nbytes + 1)) == NULL)
255 		return (NULL);
256 
257 	/* Fill the output buffer. */
258 	p = wcsarg;
259 	mbs = initial;
260 	if ((nbytes = wcsrtombs(convbuf, (const wchar_t **)&p,
261 	    nbytes, &mbs)) == (size_t)-1) {
262 		free(convbuf);
263 		return (NULL);
264 	}
265 	convbuf[nbytes] = '\0';
266 	return (convbuf);
267 }
268 
269 /*
270  * MT-safe version
271  */
272 int
273 vfprintf_l(FILE * __restrict fp, locale_t locale, const char * __restrict fmt0,
274 		va_list ap)
275 {
276 	int ret;
277 	FIX_LOCALE(locale);
278 
279 	FLOCKFILE_CANCELSAFE(fp);
280 	/* optimise fprintf(stderr) (and other unbuffered Unix files) */
281 	if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
282 	    fp->_file >= 0)
283 		ret = __sbprintf(fp, locale, fmt0, ap);
284 	else
285 		ret = __vfprintf(fp, locale, fmt0, ap);
286 	FUNLOCKFILE_CANCELSAFE();
287 	return (ret);
288 }
289 int
290 vfprintf(FILE * __restrict fp, const char * __restrict fmt0, va_list ap)
291 {
292 	return vfprintf_l(fp, __get_locale(), fmt0, ap);
293 }
294 
295 /*
296  * The size of the buffer we use as scratch space for integer
297  * conversions, among other things.  We need enough space to
298  * write a uintmax_t in octal (plus one byte).
299  */
300 #if UINTMAX_MAX <= UINT64_MAX
301 #define	BUF	32
302 #else
303 #error "BUF must be large enough to format a uintmax_t"
304 #endif
305 
306 /*
307  * Non-MT-safe version
308  */
309 int
310 __vfprintf(FILE *fp, locale_t locale, const char *fmt0, va_list ap)
311 {
312 	char *fmt;		/* format string */
313 	int ch;			/* character from fmt */
314 	int n, n2;		/* handy integer (short term usage) */
315 	char *cp;		/* handy char pointer (short term usage) */
316 	int flags;		/* flags as above */
317 	int ret;		/* return value accumulator */
318 	int width;		/* width from format (%8d), or 0 */
319 	int prec;		/* precision from format; <0 for N/A */
320 	int saved_errno;
321 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
322 	struct grouping_state gs; /* thousands' grouping info */
323 
324 #ifndef NO_FLOATING_POINT
325 	/*
326 	 * We can decompose the printed representation of floating
327 	 * point numbers into several parts, some of which may be empty:
328 	 *
329 	 * [+|-| ] [0x|0X] MMM . NNN [e|E|p|P] [+|-] ZZ
330 	 *    A       B     ---C---      D       E   F
331 	 *
332 	 * A:	'sign' holds this value if present; '\0' otherwise
333 	 * B:	ox[1] holds the 'x' or 'X'; '\0' if not hexadecimal
334 	 * C:	cp points to the string MMMNNN.  Leading and trailing
335 	 *	zeros are not in the string and must be added.
336 	 * D:	expchar holds this character; '\0' if no exponent, e.g. %f
337 	 * F:	at least two digits for decimal, at least one digit for hex
338 	 */
339 	char *decimal_point;	/* locale specific decimal point */
340 	int decpt_len;		/* length of decimal_point */
341 	int signflag;		/* true if float is negative */
342 	union {			/* floating point arguments %[aAeEfFgG] */
343 		double dbl;
344 		long double ldbl;
345 	} fparg;
346 	int expt;		/* integer value of exponent */
347 	char expchar;		/* exponent character: [eEpP\0] */
348 	char *dtoaend;		/* pointer to end of converted digits */
349 	int expsize;		/* character count for expstr */
350 	int ndig;		/* actual number of digits returned by dtoa */
351 	char expstr[MAXEXPDIG+2];	/* buffer for exponent string: e+ZZZ */
352 	char *dtoaresult;	/* buffer allocated by dtoa */
353 #endif
354 	u_long	ulval;		/* integer arguments %[diouxX] */
355 	uintmax_t ujval;	/* %j, %ll, %q, %t, %z integers */
356 	int base;		/* base for [diouxX] conversion */
357 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
358 	int realsz;		/* field size expanded by dprec, sign, etc */
359 	int size;		/* size of converted field or string */
360 	int prsize;             /* max size of printed field */
361 	const char *xdigs;     	/* digits for %[xX] conversion */
362 	struct io_state io;	/* I/O buffering state */
363 	char buf[BUF];		/* buffer with space for digits of uintmax_t */
364 	char ox[2];		/* space for 0x; ox[1] is either x, X, or \0 */
365 	union arg *argtable;    /* args, built due to positional arg */
366 	union arg statargtable [STATIC_ARG_TBL_SIZE];
367 	int nextarg;            /* 1-based argument index */
368 	va_list orgap;          /* original argument pointer */
369 	char *convbuf;		/* wide to multibyte conversion result */
370 	int savserr;
371 
372 	static const char xdigs_lower[16] = "0123456789abcdef";
373 	static const char xdigs_upper[16] = "0123456789ABCDEF";
374 
375 	/* BEWARE, these `goto error' on error. */
376 #define	PRINT(ptr, len) { \
377 	if (io_print(&io, (ptr), (len), locale))	\
378 		goto error; \
379 }
380 #define	PAD(howmany, with) { \
381 	if (io_pad(&io, (howmany), (with), locale)) \
382 		goto error; \
383 }
384 #define	PRINTANDPAD(p, ep, len, with) {	\
385 	if (io_printandpad(&io, (p), (ep), (len), (with), locale)) \
386 		goto error; \
387 }
388 #define	FLUSH() { \
389 	if (io_flush(&io, locale)) \
390 		goto error; \
391 }
392 
393 	/*
394 	 * Get the argument indexed by nextarg.   If the argument table is
395 	 * built, use it to get the argument.  If its not, get the next
396 	 * argument (and arguments must be gotten sequentially).
397 	 */
398 #define GETARG(type) \
399 	((argtable != NULL) ? *((type*)(&argtable[nextarg++])) : \
400 	    (nextarg++, va_arg(ap, type)))
401 
402 	/*
403 	 * To extend shorts properly, we need both signed and unsigned
404 	 * argument extraction methods.
405 	 */
406 #define	SARG() \
407 	(flags&LONGINT ? GETARG(long) : \
408 	    flags&SHORTINT ? (long)(short)GETARG(int) : \
409 	    flags&CHARINT ? (long)(signed char)GETARG(int) : \
410 	    (long)GETARG(int))
411 #define	UARG() \
412 	(flags&LONGINT ? GETARG(u_long) : \
413 	    flags&SHORTINT ? (u_long)(u_short)GETARG(int) : \
414 	    flags&CHARINT ? (u_long)(u_char)GETARG(int) : \
415 	    (u_long)GETARG(u_int))
416 #define	INTMAX_SIZE	(INTMAXT|SIZET|PTRDIFFT|LLONGINT)
417 #define SJARG() \
418 	(flags&INTMAXT ? GETARG(intmax_t) : \
419 	    flags&SIZET ? (intmax_t)GETARG(ssize_t) : \
420 	    flags&PTRDIFFT ? (intmax_t)GETARG(ptrdiff_t) : \
421 	    (intmax_t)GETARG(long long))
422 #define	UJARG() \
423 	(flags&INTMAXT ? GETARG(uintmax_t) : \
424 	    flags&SIZET ? (uintmax_t)GETARG(size_t) : \
425 	    flags&PTRDIFFT ? (uintmax_t)GETARG(ptrdiff_t) : \
426 	    (uintmax_t)GETARG(unsigned long long))
427 
428 	/*
429 	 * Get * arguments, including the form *nn$.  Preserve the nextarg
430 	 * that the argument can be gotten once the type is determined.
431 	 */
432 #define GETASTER(val) \
433 	n2 = 0; \
434 	cp = fmt; \
435 	while (is_digit(*cp)) { \
436 		n2 = 10 * n2 + to_digit(*cp); \
437 		cp++; \
438 	} \
439 	if (*cp == '$') { \
440 		int hold = nextarg; \
441 		if (argtable == NULL) { \
442 			argtable = statargtable; \
443 			if (__find_arguments (fmt0, orgap, &argtable)) { \
444 				ret = EOF; \
445 				goto error; \
446 			} \
447 		} \
448 		nextarg = n2; \
449 		val = GETARG (int); \
450 		nextarg = hold; \
451 		fmt = ++cp; \
452 	} else { \
453 		val = GETARG (int); \
454 	}
455 
456 	if (__use_xprintf == 0 && getenv("USE_XPRINTF"))
457 		__use_xprintf = 1;
458 	if (__use_xprintf > 0)
459 		return (__xvprintf(fp, fmt0, ap));
460 
461 	/* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
462 	if (prepwrite(fp) != 0) {
463 		errno = EBADF;
464 		return (EOF);
465 	}
466 
467 	savserr = fp->_flags & __SERR;
468 	fp->_flags &= ~__SERR;
469 
470 	saved_errno = errno;
471 	convbuf = NULL;
472 	fmt = (char *)fmt0;
473 	argtable = NULL;
474 	nextarg = 1;
475 	va_copy(orgap, ap);
476 	io_init(&io, fp);
477 	ret = 0;
478 #ifndef NO_FLOATING_POINT
479 	dtoaresult = NULL;
480 	decimal_point = localeconv_l(locale)->decimal_point;
481 	/* The overwhelmingly common case is decpt_len == 1. */
482 	decpt_len = (decimal_point[1] == '\0' ? 1 : strlen(decimal_point));
483 #endif
484 
485 	/*
486 	 * Scan the format for conversions (`%' character).
487 	 */
488 	for (;;) {
489 		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
490 			/* void */;
491 		if ((n = fmt - cp) != 0) {
492 			if ((unsigned)ret + n > INT_MAX) {
493 				ret = EOF;
494 				errno = EOVERFLOW;
495 				goto error;
496 			}
497 			PRINT(cp, n);
498 			ret += n;
499 		}
500 		if (ch == '\0')
501 			goto done;
502 		fmt++;		/* skip over '%' */
503 
504 		flags = 0;
505 		dprec = 0;
506 		width = 0;
507 		prec = -1;
508 		gs.grouping = NULL;
509 		sign = '\0';
510 		ox[1] = '\0';
511 
512 rflag:		ch = *fmt++;
513 reswitch:	switch (ch) {
514 		case ' ':
515 			/*-
516 			 * ``If the space and + flags both appear, the space
517 			 * flag will be ignored.''
518 			 *	-- ANSI X3J11
519 			 */
520 			if (!sign)
521 				sign = ' ';
522 			goto rflag;
523 		case '#':
524 			flags |= ALT;
525 			goto rflag;
526 		case '*':
527 			/*-
528 			 * ``A negative field width argument is taken as a
529 			 * - flag followed by a positive field width.''
530 			 *	-- ANSI X3J11
531 			 * They don't exclude field widths read from args.
532 			 */
533 			GETASTER (width);
534 			if (width >= 0)
535 				goto rflag;
536 			width = -width;
537 			/* FALLTHROUGH */
538 		case '-':
539 			flags |= LADJUST;
540 			goto rflag;
541 		case '+':
542 			sign = '+';
543 			goto rflag;
544 		case '\'':
545 			flags |= GROUPING;
546 			goto rflag;
547 		case '.':
548 			if ((ch = *fmt++) == '*') {
549 				GETASTER (prec);
550 				goto rflag;
551 			}
552 			prec = 0;
553 			while (is_digit(ch)) {
554 				prec = 10 * prec + to_digit(ch);
555 				ch = *fmt++;
556 			}
557 			goto reswitch;
558 		case '0':
559 			/*-
560 			 * ``Note that 0 is taken as a flag, not as the
561 			 * beginning of a field width.''
562 			 *	-- ANSI X3J11
563 			 */
564 			flags |= ZEROPAD;
565 			goto rflag;
566 		case '1': case '2': case '3': case '4':
567 		case '5': case '6': case '7': case '8': case '9':
568 			n = 0;
569 			do {
570 				n = 10 * n + to_digit(ch);
571 				ch = *fmt++;
572 			} while (is_digit(ch));
573 			if (ch == '$') {
574 				nextarg = n;
575 				if (argtable == NULL) {
576 					argtable = statargtable;
577 					if (__find_arguments (fmt0, orgap,
578 							      &argtable)) {
579 						ret = EOF;
580 						goto error;
581 					}
582 				}
583 				goto rflag;
584 			}
585 			width = n;
586 			goto reswitch;
587 #ifndef NO_FLOATING_POINT
588 		case 'L':
589 			flags |= LONGDBL;
590 			goto rflag;
591 #endif
592 		case 'h':
593 			if (flags & SHORTINT) {
594 				flags &= ~SHORTINT;
595 				flags |= CHARINT;
596 			} else
597 				flags |= SHORTINT;
598 			goto rflag;
599 		case 'j':
600 			flags |= INTMAXT;
601 			goto rflag;
602 		case 'l':
603 			if (flags & LONGINT) {
604 				flags &= ~LONGINT;
605 				flags |= LLONGINT;
606 			} else
607 				flags |= LONGINT;
608 			goto rflag;
609 		case 'q':
610 			flags |= LLONGINT;	/* not necessarily */
611 			goto rflag;
612 		case 't':
613 			flags |= PTRDIFFT;
614 			goto rflag;
615 		case 'z':
616 			flags |= SIZET;
617 			goto rflag;
618 		case 'C':
619 			flags |= LONGINT;
620 			/*FALLTHROUGH*/
621 		case 'c':
622 			if (flags & LONGINT) {
623 				static const mbstate_t initial;
624 				mbstate_t mbs;
625 				size_t mbseqlen;
626 
627 				mbs = initial;
628 				mbseqlen = wcrtomb(cp = buf,
629 				    (wchar_t)GETARG(wint_t), &mbs);
630 				if (mbseqlen == (size_t)-1) {
631 					fp->_flags |= __SERR;
632 					goto error;
633 				}
634 				size = (int)mbseqlen;
635 			} else {
636 				*(cp = buf) = GETARG(int);
637 				size = 1;
638 			}
639 			sign = '\0';
640 			break;
641 		case 'D':
642 			flags |= LONGINT;
643 			/*FALLTHROUGH*/
644 		case 'd':
645 		case 'i':
646 			if (flags & INTMAX_SIZE) {
647 				ujval = SJARG();
648 				if ((intmax_t)ujval < 0) {
649 					ujval = -ujval;
650 					sign = '-';
651 				}
652 			} else {
653 				ulval = SARG();
654 				if ((long)ulval < 0) {
655 					ulval = -ulval;
656 					sign = '-';
657 				}
658 			}
659 			base = 10;
660 			goto number;
661 #ifndef NO_FLOATING_POINT
662 		case 'a':
663 		case 'A':
664 			if (ch == 'a') {
665 				ox[1] = 'x';
666 				xdigs = xdigs_lower;
667 				expchar = 'p';
668 			} else {
669 				ox[1] = 'X';
670 				xdigs = xdigs_upper;
671 				expchar = 'P';
672 			}
673 			if (prec >= 0)
674 				prec++;
675 			if (dtoaresult != NULL)
676 				freedtoa(dtoaresult);
677 			if (flags & LONGDBL) {
678 				fparg.ldbl = GETARG(long double);
679 				dtoaresult = cp =
680 				    __hldtoa(fparg.ldbl, xdigs, prec,
681 				    &expt, &signflag, &dtoaend);
682 			} else {
683 				fparg.dbl = GETARG(double);
684 				dtoaresult = cp =
685 				    __hdtoa(fparg.dbl, xdigs, prec,
686 				    &expt, &signflag, &dtoaend);
687 			}
688 			if (prec < 0)
689 				prec = dtoaend - cp;
690 			if (expt == INT_MAX)
691 				ox[1] = '\0';
692 			goto fp_common;
693 		case 'e':
694 		case 'E':
695 			expchar = ch;
696 			if (prec < 0)	/* account for digit before decpt */
697 				prec = DEFPREC + 1;
698 			else
699 				prec++;
700 			goto fp_begin;
701 		case 'f':
702 		case 'F':
703 			expchar = '\0';
704 			goto fp_begin;
705 		case 'g':
706 		case 'G':
707 			expchar = ch - ('g' - 'e');
708 			if (prec == 0)
709 				prec = 1;
710 fp_begin:
711 			if (prec < 0)
712 				prec = DEFPREC;
713 			if (dtoaresult != NULL)
714 				freedtoa(dtoaresult);
715 			if (flags & LONGDBL) {
716 				fparg.ldbl = GETARG(long double);
717 				dtoaresult = cp =
718 				    __ldtoa(&fparg.ldbl, expchar ? 2 : 3, prec,
719 				    &expt, &signflag, &dtoaend);
720 			} else {
721 				fparg.dbl = GETARG(double);
722 				dtoaresult = cp =
723 				    dtoa(fparg.dbl, expchar ? 2 : 3, prec,
724 				    &expt, &signflag, &dtoaend);
725 				if (expt == 9999)
726 					expt = INT_MAX;
727 			}
728 fp_common:
729 			if (signflag)
730 				sign = '-';
731 			if (expt == INT_MAX) {	/* inf or nan */
732 				if (*cp == 'N') {
733 					cp = (ch >= 'a') ? "nan" : "NAN";
734 					sign = '\0';
735 				} else
736 					cp = (ch >= 'a') ? "inf" : "INF";
737 				size = 3;
738 				flags &= ~ZEROPAD;
739 				break;
740 			}
741 			flags |= FPT;
742 			ndig = dtoaend - cp;
743 			if (ch == 'g' || ch == 'G') {
744 				if (expt > -4 && expt <= prec) {
745 					/* Make %[gG] smell like %[fF] */
746 					expchar = '\0';
747 					if (flags & ALT)
748 						prec -= expt;
749 					else
750 						prec = ndig - expt;
751 					if (prec < 0)
752 						prec = 0;
753 				} else {
754 					/*
755 					 * Make %[gG] smell like %[eE], but
756 					 * trim trailing zeroes if no # flag.
757 					 */
758 					if (!(flags & ALT))
759 						prec = ndig;
760 				}
761 			}
762 			if (expchar) {
763 				expsize = exponent(expstr, expt - 1, expchar);
764 				size = expsize + prec;
765 				if (prec > 1 || flags & ALT)
766 					size += decpt_len;
767 			} else {
768 				/* space for digits before decimal point */
769 				if (expt > 0)
770 					size = expt;
771 				else	/* "0" */
772 					size = 1;
773 				/* space for decimal pt and following digits */
774 				if (prec || flags & ALT)
775 					size += prec + decpt_len;
776 				if ((flags & GROUPING) && expt > 0)
777 					size += grouping_init(&gs, expt, locale);
778 			}
779 			break;
780 #endif /* !NO_FLOATING_POINT */
781 		case 'm':
782 			cp = strerror(saved_errno);
783 			size = (prec >= 0) ? strnlen(cp, prec) : strlen(cp);
784 			sign = '\0';
785 			break;
786 		case 'n':
787 			/*
788 			 * Assignment-like behavior is specified if the
789 			 * value overflows or is otherwise unrepresentable.
790 			 * C99 says to use `signed char' for %hhn conversions.
791 			 */
792 			if (flags & LLONGINT)
793 				*GETARG(long long *) = ret;
794 			else if (flags & SIZET)
795 				*GETARG(ssize_t *) = (ssize_t)ret;
796 			else if (flags & PTRDIFFT)
797 				*GETARG(ptrdiff_t *) = ret;
798 			else if (flags & INTMAXT)
799 				*GETARG(intmax_t *) = ret;
800 			else if (flags & LONGINT)
801 				*GETARG(long *) = ret;
802 			else if (flags & SHORTINT)
803 				*GETARG(short *) = ret;
804 			else if (flags & CHARINT)
805 				*GETARG(signed char *) = ret;
806 			else
807 				*GETARG(int *) = ret;
808 			continue;	/* no output */
809 		case 'O':
810 			flags |= LONGINT;
811 			/*FALLTHROUGH*/
812 		case 'o':
813 			if (flags & INTMAX_SIZE)
814 				ujval = UJARG();
815 			else
816 				ulval = UARG();
817 			base = 8;
818 			goto nosign;
819 		case 'p':
820 			/*-
821 			 * ``The argument shall be a pointer to void.  The
822 			 * value of the pointer is converted to a sequence
823 			 * of printable characters, in an implementation-
824 			 * defined manner.''
825 			 *	-- ANSI X3J11
826 			 */
827 			ujval = (uintmax_t)(uintptr_t)GETARG(void *);
828 			base = 16;
829 			xdigs = xdigs_lower;
830 			flags = flags | INTMAXT;
831 			ox[1] = 'x';
832 			goto nosign;
833 		case 'S':
834 			flags |= LONGINT;
835 			/*FALLTHROUGH*/
836 		case 's':
837 			if (flags & LONGINT) {
838 				wchar_t *wcp;
839 
840 				if (convbuf != NULL)
841 					free(convbuf);
842 				if ((wcp = GETARG(wchar_t *)) == NULL)
843 					cp = "(null)";
844 				else {
845 					convbuf = __wcsconv(wcp, prec);
846 					if (convbuf == NULL) {
847 						fp->_flags |= __SERR;
848 						goto error;
849 					}
850 					cp = convbuf;
851 				}
852 			} else if ((cp = GETARG(char *)) == NULL)
853 				cp = "(null)";
854 			size = (prec >= 0) ? strnlen(cp, prec) : strlen(cp);
855 			sign = '\0';
856 			break;
857 		case 'U':
858 			flags |= LONGINT;
859 			/*FALLTHROUGH*/
860 		case 'u':
861 			if (flags & INTMAX_SIZE)
862 				ujval = UJARG();
863 			else
864 				ulval = UARG();
865 			base = 10;
866 			goto nosign;
867 		case 'X':
868 			xdigs = xdigs_upper;
869 			goto hex;
870 		case 'x':
871 			xdigs = xdigs_lower;
872 hex:
873 			if (flags & INTMAX_SIZE)
874 				ujval = UJARG();
875 			else
876 				ulval = UARG();
877 			base = 16;
878 			/* leading 0x/X only if non-zero */
879 			if (flags & ALT &&
880 			    (flags & INTMAX_SIZE ? ujval != 0 : ulval != 0))
881 				ox[1] = ch;
882 
883 			flags &= ~GROUPING;
884 			/* unsigned conversions */
885 nosign:			sign = '\0';
886 			/*-
887 			 * ``... diouXx conversions ... if a precision is
888 			 * specified, the 0 flag will be ignored.''
889 			 *	-- ANSI X3J11
890 			 */
891 number:			if ((dprec = prec) >= 0)
892 				flags &= ~ZEROPAD;
893 
894 			/*-
895 			 * ``The result of converting a zero value with an
896 			 * explicit precision of zero is no characters.''
897 			 *	-- ANSI X3J11
898 			 *
899 			 * ``The C Standard is clear enough as is.  The call
900 			 * printf("%#.0o", 0) should print 0.''
901 			 *	-- Defect Report #151
902 			 */
903 			cp = buf + BUF;
904 			if (flags & INTMAX_SIZE) {
905 				if (ujval != 0 || prec != 0 ||
906 				    (flags & ALT && base == 8))
907 					cp = __ujtoa(ujval, cp, base,
908 					    flags & ALT, xdigs);
909 			} else {
910 				if (ulval != 0 || prec != 0 ||
911 				    (flags & ALT && base == 8))
912 					cp = __ultoa(ulval, cp, base,
913 					    flags & ALT, xdigs);
914 			}
915 			size = buf + BUF - cp;
916 			if (size > BUF)	/* should never happen */
917 				abort();
918 			if ((flags & GROUPING) && size != 0)
919 				size += grouping_init(&gs, size, locale);
920 			break;
921 		default:	/* "%?" prints ?, unless ? is NUL */
922 			if (ch == '\0')
923 				goto done;
924 			/* pretend it was %c with argument ch */
925 			cp = buf;
926 			*cp = ch;
927 			size = 1;
928 			sign = '\0';
929 			break;
930 		}
931 
932 		/*
933 		 * All reasonable formats wind up here.  At this point, `cp'
934 		 * points to a string which (if not flags&LADJUST) should be
935 		 * padded out to `width' places.  If flags&ZEROPAD, it should
936 		 * first be prefixed by any sign or other prefix; otherwise,
937 		 * it should be blank padded before the prefix is emitted.
938 		 * After any left-hand padding and prefixing, emit zeroes
939 		 * required by a decimal [diouxX] precision, then print the
940 		 * string proper, then emit zeroes required by any leftover
941 		 * floating precision; finally, if LADJUST, pad with blanks.
942 		 *
943 		 * Compute actual size, so we know how much to pad.
944 		 * size excludes decimal prec; realsz includes it.
945 		 */
946 		realsz = dprec > size ? dprec : size;
947 		if (sign)
948 			realsz++;
949 		if (ox[1])
950 			realsz += 2;
951 
952 		prsize = width > realsz ? width : realsz;
953 		if ((unsigned)ret + prsize > INT_MAX) {
954 			ret = EOF;
955 			errno = EOVERFLOW;
956 			goto error;
957 		}
958 
959 		/* right-adjusting blank padding */
960 		if ((flags & (LADJUST|ZEROPAD)) == 0)
961 			PAD(width - realsz, blanks);
962 
963 		/* prefix */
964 		if (sign)
965 			PRINT(&sign, 1);
966 
967 		if (ox[1]) {	/* ox[1] is either x, X, or \0 */
968 			ox[0] = '0';
969 			PRINT(ox, 2);
970 		}
971 
972 		/* right-adjusting zero padding */
973 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
974 			PAD(width - realsz, zeroes);
975 
976 		/* the string or number proper */
977 #ifndef NO_FLOATING_POINT
978 		if ((flags & FPT) == 0) {
979 #endif
980 			/* leading zeroes from decimal precision */
981 			PAD(dprec - size, zeroes);
982 			if (gs.grouping) {
983 				if (grouping_print(&gs, &io, cp, buf+BUF, locale) < 0)
984 					goto error;
985 			} else {
986 				PRINT(cp, size);
987 			}
988 #ifndef NO_FLOATING_POINT
989 		} else {	/* glue together f_p fragments */
990 			if (!expchar) {	/* %[fF] or sufficiently short %[gG] */
991 				if (expt <= 0) {
992 					PRINT(zeroes, 1);
993 					if (prec || flags & ALT)
994 						PRINT(decimal_point,decpt_len);
995 					PAD(-expt, zeroes);
996 					/* already handled initial 0's */
997 					prec += expt;
998 				} else {
999 					if (gs.grouping) {
1000 						n = grouping_print(&gs, &io,
1001 						    cp, dtoaend, locale);
1002 						if (n < 0)
1003 							goto error;
1004 						cp += n;
1005 					} else {
1006 						PRINTANDPAD(cp, dtoaend,
1007 						    expt, zeroes);
1008 						cp += expt;
1009 					}
1010 					if (prec || flags & ALT)
1011 						PRINT(decimal_point,decpt_len);
1012 				}
1013 				PRINTANDPAD(cp, dtoaend, prec, zeroes);
1014 			} else {	/* %[eE] or sufficiently long %[gG] */
1015 				if (prec > 1 || flags & ALT) {
1016 					PRINT(cp++, 1);
1017 					PRINT(decimal_point, decpt_len);
1018 					PRINT(cp, ndig-1);
1019 					PAD(prec - ndig, zeroes);
1020 				} else	/* XeYYY */
1021 					PRINT(cp, 1);
1022 				PRINT(expstr, expsize);
1023 			}
1024 		}
1025 #endif
1026 		/* left-adjusting padding (always blank) */
1027 		if (flags & LADJUST)
1028 			PAD(width - realsz, blanks);
1029 
1030 		/* finally, adjust ret */
1031 		ret += prsize;
1032 
1033 		FLUSH();	/* copy out the I/O vectors */
1034 	}
1035 done:
1036 	FLUSH();
1037 error:
1038 	va_end(orgap);
1039 #ifndef NO_FLOATING_POINT
1040 	if (dtoaresult != NULL)
1041 		freedtoa(dtoaresult);
1042 #endif
1043 	if (convbuf != NULL)
1044 		free(convbuf);
1045 	if (__sferror(fp))
1046 		ret = EOF;
1047 	else
1048 		fp->_flags |= savserr;
1049 	if ((argtable != NULL) && (argtable != statargtable))
1050 		free (argtable);
1051 	return (ret);
1052 	/* NOTREACHED */
1053 }
1054 
1055