printf-pos.c revision 31980 
1/*-
2 * Copyright (c) 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#if defined(LIBC_SCCS) && !defined(lint)
38#if 0
39static char sccsid[] = "@(#)vfprintf.c	8.1 (Berkeley) 6/4/93";
40#endif
41static const char rcsid[] =
42		"$Id: vfprintf.c,v 1.14 1997/12/24 13:47:13 ache Exp $";
43#endif /* LIBC_SCCS and not lint */
44
45/*
46 * Actual printf innards.
47 *
48 * This code is large and complicated...
49 */
50
51#include <sys/types.h>
52
53#include <limits.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57
58#if __STDC__
59#include <stdarg.h>
60#else
61#include <varargs.h>
62#endif
63
64#include "local.h"
65#include "fvwrite.h"
66#ifdef _THREAD_SAFE
67#include <pthread.h>
68#include "pthread_private.h"
69#endif
70
71/* Define FLOATING_POINT to get floating point. */
72#define	FLOATING_POINT
73
74static int	__sprint __P((FILE *, struct __suio *));
75static int	__sbprintf __P((FILE *, const char *, va_list));
76static char *	__ultoa __P((u_long, char *, int, int, char *));
77static char *	__uqtoa __P((u_quad_t, char *, int, int, char *));
78static void	__find_arguments __P((const char *, va_list, void ***));
79static void	__grow_type_table __P((int, unsigned char **, int *));
80
81/*
82 * Flush out all the vectors defined by the given uio,
83 * then reset it so that it can be reused.
84 */
85static int
86__sprint(fp, uio)
87	FILE *fp;
88	register struct __suio *uio;
89{
90	register int err;
91
92	if (uio->uio_resid == 0) {
93		uio->uio_iovcnt = 0;
94		return (0);
95	}
96	err = __sfvwrite(fp, uio);
97	uio->uio_resid = 0;
98	uio->uio_iovcnt = 0;
99	return (err);
100}
101
102/*
103 * Helper function for `fprintf to unbuffered unix file': creates a
104 * temporary buffer.  We only work on write-only files; this avoids
105 * worries about ungetc buffers and so forth.
106 */
107static int
108__sbprintf(fp, fmt, ap)
109	register FILE *fp;
110	const char *fmt;
111	va_list ap;
112{
113	int ret;
114	FILE fake;
115	unsigned char buf[BUFSIZ];
116
117	/* copy the important variables */
118	fake._flags = fp->_flags & ~__SNBF;
119	fake._file = fp->_file;
120	fake._cookie = fp->_cookie;
121	fake._write = fp->_write;
122
123	/* set up the buffer */
124	fake._bf._base = fake._p = buf;
125	fake._bf._size = fake._w = sizeof(buf);
126	fake._lbfsize = 0;	/* not actually used, but Just In Case */
127
128	/* do the work, then copy any error status */
129	ret = vfprintf(&fake, fmt, ap);
130	if (ret >= 0 && fflush(&fake))
131		ret = EOF;
132	if (fake._flags & __SERR)
133		fp->_flags |= __SERR;
134	return (ret);
135}
136
137/*
138 * Macros for converting digits to letters and vice versa
139 */
140#define	to_digit(c)	((c) - '0')
141#define is_digit(c)	((unsigned)to_digit(c) <= 9)
142#define	to_char(n)	((n) + '0')
143
144/*
145 * Convert an unsigned long to ASCII for printf purposes, returning
146 * a pointer to the first character of the string representation.
147 * Octal numbers can be forced to have a leading zero; hex numbers
148 * use the given digits.
149 */
150static char *
151__ultoa(val, endp, base, octzero, xdigs)
152	register u_long val;
153	char *endp;
154	int base, octzero;
155	char *xdigs;
156{
157	register char *cp = endp;
158	register long sval;
159
160	/*
161	 * Handle the three cases separately, in the hope of getting
162	 * better/faster code.
163	 */
164	switch (base) {
165	case 10:
166		if (val < 10) {	/* many numbers are 1 digit */
167			*--cp = to_char(val);
168			return (cp);
169		}
170		/*
171		 * On many machines, unsigned arithmetic is harder than
172		 * signed arithmetic, so we do at most one unsigned mod and
173		 * divide; this is sufficient to reduce the range of
174		 * the incoming value to where signed arithmetic works.
175		 */
176		if (val > LONG_MAX) {
177			*--cp = to_char(val % 10);
178			sval = val / 10;
179		} else
180			sval = val;
181		do {
182			*--cp = to_char(sval % 10);
183			sval /= 10;
184		} while (sval != 0);
185		break;
186
187	case 8:
188		do {
189			*--cp = to_char(val & 7);
190			val >>= 3;
191		} while (val);
192		if (octzero && *cp != '0')
193			*--cp = '0';
194		break;
195
196	case 16:
197		do {
198			*--cp = xdigs[val & 15];
199			val >>= 4;
200		} while (val);
201		break;
202
203	default:			/* oops */
204		abort();
205	}
206	return (cp);
207}
208
209/* Identical to __ultoa, but for quads. */
210static char *
211__uqtoa(val, endp, base, octzero, xdigs)
212	register u_quad_t val;
213	char *endp;
214	int base, octzero;
215	char *xdigs;
216{
217	register char *cp = endp;
218	register quad_t sval;
219
220	/* quick test for small values; __ultoa is typically much faster */
221	/* (perhaps instead we should run until small, then call __ultoa?) */
222	if (val <= ULONG_MAX)
223		return (__ultoa((u_long)val, endp, base, octzero, xdigs));
224	switch (base) {
225	case 10:
226		if (val < 10) {
227			*--cp = to_char(val % 10);
228			return (cp);
229		}
230		if (val > QUAD_MAX) {
231			*--cp = to_char(val % 10);
232			sval = val / 10;
233		} else
234			sval = val;
235		do {
236			*--cp = to_char(sval % 10);
237			sval /= 10;
238		} while (sval != 0);
239		break;
240
241	case 8:
242		do {
243			*--cp = to_char(val & 7);
244			val >>= 3;
245		} while (val);
246		if (octzero && *cp != '0')
247			*--cp = '0';
248		break;
249
250	case 16:
251		do {
252			*--cp = xdigs[val & 15];
253			val >>= 4;
254		} while (val);
255		break;
256
257	default:
258		abort();
259	}
260	return (cp);
261}
262
263#ifdef FLOATING_POINT
264#include <math.h>
265#include "floatio.h"
266
267#define	BUF		(MAXEXP+MAXFRACT+1)	/* + decimal point */
268#define	DEFPREC		6
269
270static char *cvt __P((double, int, int, char *, int *, int, int *));
271static int exponent __P((char *, int, int));
272
273#else /* no FLOATING_POINT */
274
275#define	BUF		68
276
277#endif /* FLOATING_POINT */
278
279#define STATIC_ARG_TBL_SIZE 8           /* Size of static argument table. */
280
281/*
282 * Flags used during conversion.
283 */
284#define	ALT		0x001		/* alternate form */
285#define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
286#define	LADJUST		0x004		/* left adjustment */
287#define	LONGDBL		0x008		/* long double */
288#define	LONGINT		0x010		/* long integer */
289#define	QUADINT		0x020		/* quad integer */
290#define	SHORTINT	0x040		/* short integer */
291#define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
292#define FPT		0x100		/* Floating point number */
293int
294vfprintf(fp, fmt0, ap)
295	FILE *fp;
296	const char *fmt0;
297	va_list ap;
298{
299	register char *fmt;	/* format string */
300	register int ch;	/* character from fmt */
301	register int n, n2;	/* handy integer (short term usage) */
302	register char *cp;	/* handy char pointer (short term usage) */
303	register struct __siov *iovp;/* for PRINT macro */
304	register int flags;	/* flags as above */
305	int ret;		/* return value accumulator */
306	int width;		/* width from format (%8d), or 0 */
307	int prec;		/* precision from format (%.3d), or -1 */
308	char sign;		/* sign prefix (' ', '+', '-', or \0) */
309#ifdef FLOATING_POINT
310	char softsign;		/* temporary negative sign for floats */
311	double _double;		/* double precision arguments %[eEfgG] */
312	int expt;		/* integer value of exponent */
313	int expsize;		/* character count for expstr */
314	int ndig;		/* actual number of digits returned by cvt */
315	char expstr[7];		/* buffer for exponent string */
316#endif
317	u_long	ulval;		/* integer arguments %[diouxX] */
318	u_quad_t uqval;		/* %q integers */
319	int base;		/* base for [diouxX] conversion */
320	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
321	int realsz;		/* field size expanded by dprec, sign, etc */
322	int size;		/* size of converted field or string */
323	char *xdigs;		/* digits for [xX] conversion */
324#define NIOV 8
325	struct __suio uio;	/* output information: summary */
326	struct __siov iov[NIOV];/* ... and individual io vectors */
327	char buf[BUF];		/* space for %c, %[diouxX], %[eEfgG] */
328	char ox[2];		/* space for 0x hex-prefix */
329        void **argtable;        /* args, built due to positional arg */
330        void *statargtable [STATIC_ARG_TBL_SIZE];
331        int nextarg;            /* 1-based argument index */
332        va_list orgap;          /* original argument pointer */
333
334	/*
335	 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
336	 * fields occur frequently, increase PADSIZE and make the initialisers
337	 * below longer.
338	 */
339#define	PADSIZE	16		/* pad chunk size */
340	static char blanks[PADSIZE] =
341	 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
342	static char zeroes[PADSIZE] =
343	 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
344
345	/*
346	 * BEWARE, these `goto error' on error, and PAD uses `n'.
347	 */
348#define	PRINT(ptr, len) { \
349	iovp->iov_base = (ptr); \
350	iovp->iov_len = (len); \
351	uio.uio_resid += (len); \
352	iovp++; \
353	if (++uio.uio_iovcnt >= NIOV) { \
354		if (__sprint(fp, &uio)) \
355			goto error; \
356		iovp = iov; \
357	} \
358}
359#define	PAD(howmany, with) { \
360	if ((n = (howmany)) > 0) { \
361		while (n > PADSIZE) { \
362			PRINT(with, PADSIZE); \
363			n -= PADSIZE; \
364		} \
365		PRINT(with, n); \
366	} \
367}
368#define	FLUSH() { \
369	if (uio.uio_resid && __sprint(fp, &uio)) \
370		goto error; \
371	uio.uio_iovcnt = 0; \
372	iovp = iov; \
373}
374
375        /*
376         * Get the argument indexed by nextarg.   If the argument table is
377         * built, use it to get the argument.  If its not, get the next
378         * argument (and arguments must be gotten sequentially).
379         */
380#define GETARG(type) \
381        ((argtable != NULL) ? *((type*)(argtable[nextarg++])) : \
382            (nextarg++, va_arg(ap, type)))
383
384	/*
385	 * To extend shorts properly, we need both signed and unsigned
386	 * argument extraction methods.
387	 */
388#define	SARG() \
389	(flags&LONGINT ? GETARG(long) : \
390	    flags&SHORTINT ? (long)(short)GETARG(int) : \
391	    (long)GETARG(int))
392#define	UARG() \
393	(flags&LONGINT ? GETARG(u_long) : \
394	    flags&SHORTINT ? (u_long)(u_short)GETARG(int) : \
395	    (u_long)GETARG(u_int))
396
397        /*
398         * Get * arguments, including the form *nn$.  Preserve the nextarg
399         * that the argument can be gotten once the type is determined.
400         */
401#define GETASTER(val) \
402        n2 = 0; \
403        cp = fmt; \
404        while (is_digit(*cp)) { \
405                n2 = 10 * n2 + to_digit(*cp); \
406                cp++; \
407        } \
408        if (*cp == '$') { \
409            	int hold = nextarg; \
410                if (argtable == NULL) { \
411                        argtable = statargtable; \
412                        __find_arguments (fmt0, orgap, &argtable); \
413                } \
414                nextarg = n2; \
415                val = GETARG (int); \
416                nextarg = hold; \
417                fmt = ++cp; \
418        } else { \
419		val = GETARG (int); \
420        }
421
422
423#ifdef _THREAD_SAFE
424	_thread_flockfile(fp,__FILE__,__LINE__);
425#endif
426	/* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
427	if (cantwrite(fp)) {
428#ifdef _THREAD_SAFE
429		_thread_funlockfile(fp);
430#endif
431		return (EOF);
432	}
433
434	/* optimise fprintf(stderr) (and other unbuffered Unix files) */
435	if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
436	    fp->_file >= 0) {
437#ifdef _THREAD_SAFE
438		_thread_funlockfile(fp);
439#endif
440		return (__sbprintf(fp, fmt0, ap));
441	}
442
443	fmt = (char *)fmt0;
444        argtable = NULL;
445        nextarg = 1;
446        orgap = ap;
447	uio.uio_iov = iovp = iov;
448	uio.uio_resid = 0;
449	uio.uio_iovcnt = 0;
450	ret = 0;
451
452	/*
453	 * Scan the format for conversions (`%' character).
454	 */
455	for (;;) {
456		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
457			/* void */;
458		if ((n = fmt - cp) != 0) {
459			PRINT(cp, n);
460			ret += n;
461		}
462		if (ch == '\0')
463			goto done;
464		fmt++;		/* skip over '%' */
465
466		flags = 0;
467		dprec = 0;
468		width = 0;
469		prec = -1;
470		sign = '\0';
471
472rflag:		ch = *fmt++;
473reswitch:	switch (ch) {
474		case ' ':
475			/*
476			 * ``If the space and + flags both appear, the space
477			 * flag will be ignored.''
478			 *	-- ANSI X3J11
479			 */
480			if (!sign)
481				sign = ' ';
482			goto rflag;
483		case '#':
484			flags |= ALT;
485			goto rflag;
486		case '*':
487			/*
488			 * ``A negative field width argument is taken as a
489			 * - flag followed by a positive field width.''
490			 *	-- ANSI X3J11
491			 * They don't exclude field widths read from args.
492			 */
493			GETASTER (width);
494			if (width >= 0)
495				goto rflag;
496			width = -width;
497			/* FALLTHROUGH */
498		case '-':
499			flags |= LADJUST;
500			goto rflag;
501		case '+':
502			sign = '+';
503			goto rflag;
504		case '.':
505			if ((ch = *fmt++) == '*') {
506				GETASTER (n);
507				prec = n < 0 ? -1 : n;
508				goto rflag;
509			}
510			n = 0;
511			while (is_digit(ch)) {
512				n = 10 * n + to_digit(ch);
513				ch = *fmt++;
514			}
515			prec = n < 0 ? -1 : n;
516			goto reswitch;
517		case '0':
518			/*
519			 * ``Note that 0 is taken as a flag, not as the
520			 * beginning of a field width.''
521			 *	-- ANSI X3J11
522			 */
523			flags |= ZEROPAD;
524			goto rflag;
525		case '1': case '2': case '3': case '4':
526		case '5': case '6': case '7': case '8': case '9':
527			n = 0;
528			do {
529				n = 10 * n + to_digit(ch);
530				ch = *fmt++;
531			} while (is_digit(ch));
532			if (ch == '$') {
533				nextarg = n;
534                        	if (argtable == NULL) {
535                                	argtable = statargtable;
536                                	__find_arguments (fmt0, orgap,
537						&argtable);
538				}
539				goto rflag;
540                        }
541			width = n;
542			goto reswitch;
543#ifdef FLOATING_POINT
544		case 'L':
545			flags |= LONGDBL;
546			goto rflag;
547#endif
548		case 'h':
549			flags |= SHORTINT;
550			goto rflag;
551		case 'l':
552			flags |= LONGINT;
553			goto rflag;
554		case 'q':
555			flags |= QUADINT;
556			goto rflag;
557		case 'c':
558			*(cp = buf) = GETARG(int);
559			size = 1;
560			sign = '\0';
561			break;
562		case 'D':
563			flags |= LONGINT;
564			/*FALLTHROUGH*/
565		case 'd':
566		case 'i':
567			if (flags & QUADINT) {
568				uqval = GETARG(quad_t);
569				if ((quad_t)uqval < 0) {
570					uqval = -uqval;
571					sign = '-';
572				}
573			} else {
574				ulval = SARG();
575				if ((long)ulval < 0) {
576					ulval = -ulval;
577					sign = '-';
578				}
579			}
580			base = 10;
581			goto number;
582#ifdef FLOATING_POINT
583		case 'e':
584		case 'E':
585		case 'f':
586			goto fp_begin;
587		case 'g':
588		case 'G':
589			if (prec == 0)
590				prec = 1;
591fp_begin:		if (prec == -1)
592				prec = DEFPREC;
593			if (flags & LONGDBL)
594				/* XXX this loses precision. */
595				_double = (double)GETARG(long double);
596			else
597				_double = GETARG(double);
598			/* do this before tricky precision changes */
599			if (isinf(_double)) {
600				if (_double < 0)
601					sign = '-';
602				cp = "Inf";
603				size = 3;
604				break;
605			}
606			if (isnan(_double)) {
607				cp = "NaN";
608				size = 3;
609				break;
610			}
611			flags |= FPT;
612			cp = cvt(_double, prec, flags, &softsign,
613				&expt, ch, &ndig);
614			if (ch == 'g' || ch == 'G') {
615				if (expt <= -4 || expt > prec)
616					ch = (ch == 'g') ? 'e' : 'E';
617				else
618					ch = 'g';
619			}
620			if (ch <= 'e') {	/* 'e' or 'E' fmt */
621				--expt;
622				expsize = exponent(expstr, expt, ch);
623				size = expsize + ndig;
624				if (ndig > 1 || flags & ALT)
625					++size;
626			} else if (ch == 'f') {		/* f fmt */
627				if (expt > 0) {
628					size = expt;
629					if (prec || flags & ALT)
630						size += prec + 1;
631				} else	/* "0.X" */
632					size = prec + 2;
633			} else if (expt >= ndig) {	/* fixed g fmt */
634				size = expt;
635				if (flags & ALT)
636					++size;
637			} else
638				size = ndig + (expt > 0 ?
639					1 : 2 - expt);
640
641			if (softsign)
642				sign = '-';
643			break;
644#endif /* FLOATING_POINT */
645		case 'n':
646			if (flags & QUADINT)
647				*GETARG(quad_t *) = ret;
648			else if (flags & LONGINT)
649				*GETARG(long *) = ret;
650			else if (flags & SHORTINT)
651				*GETARG(short *) = ret;
652			else
653				*GETARG(int *) = ret;
654			continue;	/* no output */
655		case 'O':
656			flags |= LONGINT;
657			/*FALLTHROUGH*/
658		case 'o':
659			if (flags & QUADINT)
660				uqval = GETARG(u_quad_t);
661			else
662				ulval = UARG();
663			base = 8;
664			goto nosign;
665		case 'p':
666			/*
667			 * ``The argument shall be a pointer to void.  The
668			 * value of the pointer is converted to a sequence
669			 * of printable characters, in an implementation-
670			 * defined manner.''
671			 *	-- ANSI X3J11
672			 */
673			ulval = (u_long)GETARG(void *);
674			base = 16;
675			xdigs = "0123456789abcdef";
676			flags = (flags & ~QUADINT) | HEXPREFIX;
677			ch = 'x';
678			goto nosign;
679		case 's':
680			if ((cp = GETARG(char *)) == NULL)
681				cp = "(null)";
682			if (prec >= 0) {
683				/*
684				 * can't use strlen; can only look for the
685				 * NUL in the first `prec' characters, and
686				 * strlen() will go further.
687				 */
688				char *p = memchr(cp, 0, (size_t)prec);
689
690				if (p != NULL) {
691					size = p - cp;
692					if (size > prec)
693						size = prec;
694				} else
695					size = prec;
696			} else
697				size = strlen(cp);
698			sign = '\0';
699			break;
700		case 'U':
701			flags |= LONGINT;
702			/*FALLTHROUGH*/
703		case 'u':
704			if (flags & QUADINT)
705				uqval = GETARG(u_quad_t);
706			else
707				ulval = UARG();
708			base = 10;
709			goto nosign;
710		case 'X':
711			xdigs = "0123456789ABCDEF";
712			goto hex;
713		case 'x':
714			xdigs = "0123456789abcdef";
715hex:			if (flags & QUADINT)
716				uqval = GETARG(u_quad_t);
717			else
718				ulval = UARG();
719			base = 16;
720			/* leading 0x/X only if non-zero */
721			if (flags & ALT &&
722			    (flags & QUADINT ? uqval != 0 : ulval != 0))
723				flags |= HEXPREFIX;
724
725			/* unsigned conversions */
726nosign:			sign = '\0';
727			/*
728			 * ``... diouXx conversions ... if a precision is
729			 * specified, the 0 flag will be ignored.''
730			 *	-- ANSI X3J11
731			 */
732number:			if ((dprec = prec) >= 0)
733				flags &= ~ZEROPAD;
734
735			/*
736			 * ``The result of converting a zero value with an
737			 * explicit precision of zero is no characters.''
738			 *	-- ANSI X3J11
739			 */
740			cp = buf + BUF;
741			if (flags & QUADINT) {
742				if (uqval != 0 || prec != 0)
743					cp = __uqtoa(uqval, cp, base,
744					    flags & ALT, xdigs);
745			} else {
746				if (ulval != 0 || prec != 0)
747					cp = __ultoa(ulval, cp, base,
748					    flags & ALT, xdigs);
749			}
750			size = buf + BUF - cp;
751			break;
752		default:	/* "%?" prints ?, unless ? is NUL */
753			if (ch == '\0')
754				goto done;
755			/* pretend it was %c with argument ch */
756			cp = buf;
757			*cp = ch;
758			size = 1;
759			sign = '\0';
760			break;
761		}
762
763		/*
764		 * All reasonable formats wind up here.  At this point, `cp'
765		 * points to a string which (if not flags&LADJUST) should be
766		 * padded out to `width' places.  If flags&ZEROPAD, it should
767		 * first be prefixed by any sign or other prefix; otherwise,
768		 * it should be blank padded before the prefix is emitted.
769		 * After any left-hand padding and prefixing, emit zeroes
770		 * required by a decimal [diouxX] precision, then print the
771		 * string proper, then emit zeroes required by any leftover
772		 * floating precision; finally, if LADJUST, pad with blanks.
773		 *
774		 * Compute actual size, so we know how much to pad.
775		 * size excludes decimal prec; realsz includes it.
776		 */
777		realsz = dprec > size ? dprec : size;
778		if (sign)
779			realsz++;
780		else if (flags & HEXPREFIX)
781			realsz += 2;
782
783		/* right-adjusting blank padding */
784		if ((flags & (LADJUST|ZEROPAD)) == 0)
785			PAD(width - realsz, blanks);
786
787		/* prefix */
788		if (sign) {
789			PRINT(&sign, 1);
790		} else if (flags & HEXPREFIX) {
791			ox[0] = '0';
792			ox[1] = ch;
793			PRINT(ox, 2);
794		}
795
796		/* right-adjusting zero padding */
797		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
798			PAD(width - realsz, zeroes);
799
800		/* leading zeroes from decimal precision */
801		PAD(dprec - size, zeroes);
802
803		/* the string or number proper */
804#ifdef FLOATING_POINT
805		if ((flags & FPT) == 0) {
806			PRINT(cp, size);
807		} else {	/* glue together f_p fragments */
808			if (ch >= 'f') {	/* 'f' or 'g' */
809				if (_double == 0) {
810					/* kludge for __dtoa irregularity */
811					if (expt >= ndig &&
812					    (flags & ALT) == 0) {
813						PRINT("0", 1);
814					} else {
815						PRINT("0.", 2);
816						PAD(ndig - 1, zeroes);
817					}
818				} else if (expt <= 0) {
819					PRINT("0.", 2);
820					PAD(-expt, zeroes);
821					PRINT(cp, ndig);
822				} else if (expt >= ndig) {
823					PRINT(cp, ndig);
824					PAD(expt - ndig, zeroes);
825					if (flags & ALT)
826						PRINT(".", 1);
827				} else {
828					PRINT(cp, expt);
829					cp += expt;
830					PRINT(".", 1);
831					PRINT(cp, ndig-expt);
832				}
833			} else {	/* 'e' or 'E' */
834				if (ndig > 1 || flags & ALT) {
835					ox[0] = *cp++;
836					ox[1] = '.';
837					PRINT(ox, 2);
838					if (_double) {
839						PRINT(cp, ndig-1);
840					} else	/* 0.[0..] */
841						/* __dtoa irregularity */
842						PAD(ndig - 1, zeroes);
843				} else	/* XeYYY */
844					PRINT(cp, 1);
845				PRINT(expstr, expsize);
846			}
847		}
848#else
849		PRINT(cp, size);
850#endif
851		/* left-adjusting padding (always blank) */
852		if (flags & LADJUST)
853			PAD(width - realsz, blanks);
854
855		/* finally, adjust ret */
856		ret += width > realsz ? width : realsz;
857
858		FLUSH();	/* copy out the I/O vectors */
859	}
860done:
861	FLUSH();
862error:
863	if (__sferror(fp))
864		ret = EOF;
865#ifdef _THREAD_SAFE
866	_thread_funlockfile(fp);
867#endif
868        if ((argtable != NULL) && (argtable != statargtable))
869                free (argtable);
870	return (ret);
871	/* NOTREACHED */
872}
873
874/*
875 * Type ids for argument type table.
876 */
877#define T_UNUSED	0
878#define T_SHORT		1
879#define T_U_SHORT	2
880#define TP_SHORT	3
881#define T_INT		4
882#define T_U_INT		5
883#define TP_INT		6
884#define T_LONG		7
885#define T_U_LONG	8
886#define TP_LONG		9
887#define T_QUAD		10
888#define T_U_QUAD	11
889#define TP_QUAD		12
890#define T_DOUBLE	13
891#define T_LONG_DOUBLE	14
892#define TP_CHAR		15
893#define TP_VOID		16
894
895/*
896 * Find all arguments when a positional parameter is encountered.  Returns a
897 * table, indexed by argument number, of pointers to each arguments.  The
898 * initial argument table should be an array of STATIC_ARG_TBL_SIZE entries.
899 * It will be replaces with a malloc-ed on if it overflows.
900 */
901static void
902__find_arguments (fmt0, ap, argtable)
903	const char *fmt0;
904	va_list ap;
905	void ***argtable;
906{
907	register char *fmt;	/* format string */
908	register int ch;	/* character from fmt */
909	register int n, n2;	/* handy integer (short term usage) */
910	register char *cp;	/* handy char pointer (short term usage) */
911	register int flags;	/* flags as above */
912	int width;		/* width from format (%8d), or 0 */
913	unsigned char *typetable; /* table of types */
914	unsigned char stattypetable [STATIC_ARG_TBL_SIZE];
915	int tablesize;		/* current size of type table */
916	int tablemax;		/* largest used index in table */
917	int nextarg;		/* 1-based argument index */
918
919	/*
920	 * Add an argument type to the table, expanding if necessary.
921	 */
922#define ADDTYPE(type) \
923	((nextarg >= tablesize) ? \
924		__grow_type_table(nextarg, &typetable, &tablesize) : 0, \
925	typetable[nextarg++] = type, \
926	(nextarg > tablemax) ? tablemax = nextarg : 0)
927
928#define	ADDSARG() \
929	((flags&LONGINT) ? ADDTYPE(T_LONG) : \
930		((flags&SHORTINT) ? ADDTYPE(T_SHORT) : ADDTYPE(T_INT)))
931
932#define	ADDUARG() \
933	((flags&LONGINT) ? ADDTYPE(T_U_LONG) : \
934		((flags&SHORTINT) ? ADDTYPE(T_U_SHORT) : ADDTYPE(T_U_INT)))
935
936	/*
937	 * Add * arguments to the type array.
938	 */
939#define ADDASTER() \
940	n2 = 0; \
941	cp = fmt; \
942	while (is_digit(*cp)) { \
943		n2 = 10 * n2 + to_digit(*cp); \
944		cp++; \
945	} \
946	if (*cp == '$') { \
947		int hold = nextarg; \
948		nextarg = n2; \
949		ADDTYPE (T_INT); \
950		nextarg = hold; \
951		fmt = ++cp; \
952	} else { \
953		ADDTYPE (T_INT); \
954	}
955	fmt = (char *)fmt0;
956	typetable = stattypetable;
957	tablesize = STATIC_ARG_TBL_SIZE;
958	tablemax = 0;
959	nextarg = 1;
960	memset (typetable, T_UNUSED, STATIC_ARG_TBL_SIZE);
961
962	/*
963	 * Scan the format for conversions (`%' character).
964	 */
965	for (;;) {
966		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
967			/* void */;
968		if (ch == '\0')
969			goto done;
970		fmt++;		/* skip over '%' */
971
972		flags = 0;
973		width = 0;
974
975rflag:		ch = *fmt++;
976reswitch:	switch (ch) {
977		case ' ':
978		case '#':
979			goto rflag;
980		case '*':
981			ADDASTER ();
982			goto rflag;
983		case '-':
984		case '+':
985			goto rflag;
986		case '.':
987			if ((ch = *fmt++) == '*') {
988				ADDASTER ();
989				goto rflag;
990			}
991			while (is_digit(ch)) {
992				ch = *fmt++;
993			}
994			goto reswitch;
995		case '0':
996			goto rflag;
997		case '1': case '2': case '3': case '4':
998		case '5': case '6': case '7': case '8': case '9':
999			n = 0;
1000			do {
1001				n = 10 * n + to_digit(ch);
1002				ch = *fmt++;
1003			} while (is_digit(ch));
1004			if (ch == '$') {
1005				nextarg = n;
1006				goto rflag;
1007			}
1008			width = n;
1009			goto reswitch;
1010#ifdef FLOATING_POINT
1011		case 'L':
1012			flags |= LONGDBL;
1013			goto rflag;
1014#endif
1015		case 'h':
1016			flags |= SHORTINT;
1017			goto rflag;
1018		case 'l':
1019			flags |= LONGINT;
1020			goto rflag;
1021		case 'q':
1022			flags |= QUADINT;
1023			goto rflag;
1024		case 'c':
1025			ADDTYPE(T_INT);
1026			break;
1027		case 'D':
1028			flags |= LONGINT;
1029			/*FALLTHROUGH*/
1030		case 'd':
1031		case 'i':
1032			if (flags & QUADINT) {
1033				ADDTYPE(T_QUAD);
1034			} else {
1035				ADDSARG();
1036			}
1037			break;
1038#ifdef FLOATING_POINT
1039		case 'e':
1040		case 'E':
1041		case 'f':
1042		case 'g':
1043		case 'G':
1044			if (flags & LONGDBL)
1045				ADDTYPE(T_LONG_DOUBLE);
1046			else
1047				ADDTYPE(T_DOUBLE);
1048			break;
1049#endif /* FLOATING_POINT */
1050		case 'n':
1051			if (flags & QUADINT)
1052				ADDTYPE(TP_QUAD);
1053			else if (flags & LONGINT)
1054				ADDTYPE(TP_LONG);
1055			else if (flags & SHORTINT)
1056				ADDTYPE(TP_SHORT);
1057			else
1058				ADDTYPE(TP_INT);
1059			continue;	/* no output */
1060		case 'O':
1061			flags |= LONGINT;
1062			/*FALLTHROUGH*/
1063		case 'o':
1064			if (flags & QUADINT)
1065				ADDTYPE(T_U_QUAD);
1066			else
1067				ADDUARG();
1068			break;
1069		case 'p':
1070			ADDTYPE(TP_VOID);
1071			break;
1072		case 's':
1073			ADDTYPE(TP_CHAR);
1074			break;
1075		case 'U':
1076			flags |= LONGINT;
1077			/*FALLTHROUGH*/
1078		case 'u':
1079			if (flags & QUADINT)
1080				ADDTYPE(T_U_QUAD);
1081			else
1082				ADDUARG();
1083			break;
1084		case 'X':
1085		case 'x':
1086			if (flags & QUADINT)
1087				ADDTYPE(T_U_QUAD);
1088			else
1089				ADDUARG();
1090			break;
1091		default:	/* "%?" prints ?, unless ? is NUL */
1092			if (ch == '\0')
1093				goto done;
1094			break;
1095		}
1096	}
1097done:
1098	/*
1099	 * Build the argument table.
1100	 */
1101	if (tablemax >= STATIC_ARG_TBL_SIZE) {
1102		*argtable = (void **)
1103		    malloc (sizeof (void *) * (tablemax + 1));
1104	}
1105
1106	(*argtable) [0] = NULL;
1107	for (n = 1; n <= tablemax; n++) {
1108		(*argtable) [n] = ap;
1109		switch (typetable [n]) {
1110		    case T_UNUSED:
1111			(void) va_arg (ap, int);
1112			break;
1113		    case T_SHORT:
1114			(void) va_arg (ap, int);
1115			break;
1116		    case T_U_SHORT:
1117			(void) va_arg (ap, int);
1118			break;
1119		    case TP_SHORT:
1120			(void) va_arg (ap, short *);
1121			break;
1122		    case T_INT:
1123			(void) va_arg (ap, int);
1124			break;
1125		    case T_U_INT:
1126			(void) va_arg (ap, unsigned int);
1127			break;
1128		    case TP_INT:
1129			(void) va_arg (ap, int *);
1130			break;
1131		    case T_LONG:
1132			(void) va_arg (ap, long);
1133			break;
1134		    case T_U_LONG:
1135			(void) va_arg (ap, unsigned long);
1136			break;
1137		    case TP_LONG:
1138			(void) va_arg (ap, long *);
1139			break;
1140		    case T_QUAD:
1141			(void) va_arg (ap, quad_t);
1142			break;
1143		    case T_U_QUAD:
1144			(void) va_arg (ap, u_quad_t);
1145			break;
1146		    case TP_QUAD:
1147			(void) va_arg (ap, quad_t *);
1148			break;
1149		    case T_DOUBLE:
1150			(void) va_arg (ap, double);
1151			break;
1152		    case T_LONG_DOUBLE:
1153			(void) va_arg (ap, long double);
1154			break;
1155		    case TP_CHAR:
1156			(void) va_arg (ap, char *);
1157			break;
1158		    case TP_VOID:
1159			(void) va_arg (ap, void *);
1160			break;
1161		}
1162	}
1163
1164	if ((typetable != NULL) && (typetable != stattypetable))
1165		free (typetable);
1166}
1167
1168/*
1169 * Increase the size of the type table.
1170 */
1171static void
1172__grow_type_table (nextarg, typetable, tablesize)
1173	int nextarg;
1174	unsigned char **typetable;
1175	int *tablesize;
1176{
1177	unsigned char *oldtable = *typetable;
1178	int newsize = *tablesize * 2;
1179
1180	if (*tablesize == STATIC_ARG_TBL_SIZE) {
1181		*typetable = (unsigned char *)
1182		    malloc (sizeof (unsigned char) * newsize);
1183		bcopy (oldtable, *typetable, *tablesize);
1184	} else {
1185		*typetable = (unsigned char *)
1186		    realloc (typetable, sizeof (unsigned char) * newsize);
1187
1188	}
1189	memset (&typetable [*tablesize], T_UNUSED, (newsize - *tablesize));
1190
1191	*tablesize = newsize;
1192}
1193
1194
1195#ifdef FLOATING_POINT
1196
1197extern char *__dtoa __P((double, int, int, int *, int *, char **));
1198
1199static char *
1200cvt(value, ndigits, flags, sign, decpt, ch, length)
1201	double value;
1202	int ndigits, flags, *decpt, ch, *length;
1203	char *sign;
1204{
1205	int mode, dsgn;
1206	char *digits, *bp, *rve;
1207
1208	if (ch == 'f')
1209		mode = 3;		/* ndigits after the decimal point */
1210	else {
1211		/*
1212		 * To obtain ndigits after the decimal point for the 'e'
1213		 * and 'E' formats, round to ndigits + 1 significant
1214		 * figures.
1215		 */
1216		if (ch == 'e' || ch == 'E')
1217			ndigits++;
1218		mode = 2;		/* ndigits significant digits */
1219	}
1220	if (value < 0) {
1221		value = -value;
1222		*sign = '-';
1223	} else
1224		*sign = '\000';
1225	digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
1226	if ((ch != 'g' && ch != 'G') || flags & ALT) {
1227		/* print trailing zeros */
1228		bp = digits + ndigits;
1229		if (ch == 'f') {
1230			if (*digits == '0' && value)
1231				*decpt = -ndigits + 1;
1232			bp += *decpt;
1233		}
1234		if (value == 0)	/* kludge for __dtoa irregularity */
1235			rve = bp;
1236		while (rve < bp)
1237			*rve++ = '0';
1238	}
1239	*length = rve - digits;
1240	return (digits);
1241}
1242
1243static int
1244exponent(p0, exp, fmtch)
1245	char *p0;
1246	int exp, fmtch;
1247{
1248	register char *p, *t;
1249	char expbuf[MAXEXP];
1250
1251	p = p0;
1252	*p++ = fmtch;
1253	if (exp < 0) {
1254		exp = -exp;
1255		*p++ = '-';
1256	}
1257	else
1258		*p++ = '+';
1259	t = expbuf + MAXEXP;
1260	if (exp > 9) {
1261		do {
1262			*--t = to_char(exp % 10);
1263		} while ((exp /= 10) > 9);
1264		*--t = to_char(exp);
1265		for (; t < expbuf + MAXEXP; *p++ = *t++);
1266	}
1267	else {
1268		*p++ = '0';
1269		*p++ = to_char(exp);
1270	}
1271	return (p - p0);
1272}
1273#endif /* FLOATING_POINT */
1274