vfprintf.c revision 70725
1178172Simp/*-
2178172Simp * Copyright (c) 1990, 1993
3178172Simp *	The Regents of the University of California.  All rights reserved.
4178172Simp *
5178172Simp * This code is derived from software contributed to Berkeley by
6178172Simp * Chris Torek.
7178172Simp *
8178172Simp * Redistribution and use in source and binary forms, with or without
9178172Simp * modification, are permitted provided that the following conditions
10178172Simp * are met:
11178172Simp * 1. Redistributions of source code must retain the above copyright
12178172Simp *    notice, this list of conditions and the following disclaimer.
13178172Simp * 2. Redistributions in binary form must reproduce the above copyright
14178172Simp *    notice, this list of conditions and the following disclaimer in the
15178172Simp *    documentation and/or other materials provided with the distribution.
16178172Simp * 3. All advertising materials mentioning features or use of this software
17178172Simp *    must display the following acknowledgement:
18178172Simp *	This product includes software developed by the University of
19178172Simp *	California, Berkeley and its contributors.
20178172Simp * 4. Neither the name of the University nor the names of its contributors
21178172Simp *    may be used to endorse or promote products derived from this software
22178172Simp *    without specific prior written permission.
23178172Simp *
24178172Simp * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25178172Simp * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26178172Simp * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27178172Simp * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28178172Simp * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29178172Simp * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30178172Simp * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31178172Simp * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32178172Simp * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33178172Simp * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34178172Simp * SUCH DAMAGE.
35178172Simp */
36178172Simp
37178172Simp#if defined(LIBC_SCCS) && !defined(lint)
38178172Simp#if 0
39178172Simpstatic char sccsid[] = "@(#)vfprintf.c	8.1 (Berkeley) 6/4/93";
40178172Simp#endif
41178172Simpstatic const char rcsid[] =
42178172Simp  "$FreeBSD: head/lib/libc/stdio/vfprintf.c 70725 2001-01-06 20:48:00Z archie $";
43178172Simp#endif /* LIBC_SCCS and not lint */
44178172Simp
45178172Simp/*
46178172Simp * Actual printf innards.
47178172Simp *
48211862Sjchandra * This code is large and complicated...
49211862Sjchandra */
50211862Sjchandra
51211862Sjchandra#include <sys/types.h>
52211862Sjchandra
53211862Sjchandra#include <limits.h>
54211862Sjchandra#include <stdio.h>
55211862Sjchandra#include <stdlib.h>
56211862Sjchandra#include <string.h>
57211862Sjchandra
58211862Sjchandra#if __STDC__
59211862Sjchandra#include <stdarg.h>
60211862Sjchandra#else
61211862Sjchandra#include <varargs.h>
62178172Simp#endif
63249882Simp
64249882Simp#include "local.h"
65178172Simp#include "fvwrite.h"
66249882Simp#include "libc_private.h"
67249882Simp
68249882Simp/* Define FLOATING_POINT to get floating point. */
69249882Simp#define	FLOATING_POINT
70249882Simp
71249882Simpstatic int	__sprint __P((FILE *, struct __suio *));
72249882Simpstatic int	__sbprintf __P((FILE *, const char *, va_list));
73249882Simpstatic char *	__ultoa __P((u_long, char *, int, int, char *));
74249882Simpstatic char *	__uqtoa __P((u_quad_t, char *, int, int, char *));
75249882Simpstatic void	__find_arguments __P((const char *, va_list, void ***));
76249882Simpstatic void	__grow_type_table __P((int, unsigned char **, int *));
77178172Simp
78178172Simp/*
79178172Simp * Flush out all the vectors defined by the given uio,
80178172Simp * then reset it so that it can be reused.
81234785Sdim */
82178172Simpstatic int
83249882Simp__sprint(fp, uio)
84178172Simp	FILE *fp;
85178172Simp	register struct __suio *uio;
86{
87	register int err;
88
89	if (uio->uio_resid == 0) {
90		uio->uio_iovcnt = 0;
91		return (0);
92	}
93	err = __sfvwrite(fp, uio);
94	uio->uio_resid = 0;
95	uio->uio_iovcnt = 0;
96	return (err);
97}
98
99/*
100 * Helper function for `fprintf to unbuffered unix file': creates a
101 * temporary buffer.  We only work on write-only files; this avoids
102 * worries about ungetc buffers and so forth.
103 */
104static int
105__sbprintf(fp, fmt, ap)
106	register FILE *fp;
107	const char *fmt;
108	va_list ap;
109{
110	int ret;
111	FILE fake;
112	unsigned char buf[BUFSIZ];
113
114	/* copy the important variables */
115	fake._flags = fp->_flags & ~__SNBF;
116	fake._file = fp->_file;
117	fake._cookie = fp->_cookie;
118	fake._write = fp->_write;
119
120	/* set up the buffer */
121	fake._bf._base = fake._p = buf;
122	fake._bf._size = fake._w = sizeof(buf);
123	fake._lbfsize = 0;	/* not actually used, but Just In Case */
124
125	/* do the work, then copy any error status */
126	ret = vfprintf(&fake, fmt, ap);
127	if (ret >= 0 && fflush(&fake))
128		ret = EOF;
129	if (fake._flags & __SERR)
130		fp->_flags |= __SERR;
131	return (ret);
132}
133
134/*
135 * Macros for converting digits to letters and vice versa
136 */
137#define	to_digit(c)	((c) - '0')
138#define is_digit(c)	((unsigned)to_digit(c) <= 9)
139#define	to_char(n)	((n) + '0')
140
141/*
142 * Convert an unsigned long to ASCII for printf purposes, returning
143 * a pointer to the first character of the string representation.
144 * Octal numbers can be forced to have a leading zero; hex numbers
145 * use the given digits.
146 */
147static char *
148__ultoa(val, endp, base, octzero, xdigs)
149	register u_long val;
150	char *endp;
151	int base, octzero;
152	char *xdigs;
153{
154	register char *cp = endp;
155	register long sval;
156
157	/*
158	 * Handle the three cases separately, in the hope of getting
159	 * better/faster code.
160	 */
161	switch (base) {
162	case 10:
163		if (val < 10) {	/* many numbers are 1 digit */
164			*--cp = to_char(val);
165			return (cp);
166		}
167		/*
168		 * On many machines, unsigned arithmetic is harder than
169		 * signed arithmetic, so we do at most one unsigned mod and
170		 * divide; this is sufficient to reduce the range of
171		 * the incoming value to where signed arithmetic works.
172		 */
173		if (val > LONG_MAX) {
174			*--cp = to_char(val % 10);
175			sval = val / 10;
176		} else
177			sval = val;
178		do {
179			*--cp = to_char(sval % 10);
180			sval /= 10;
181		} while (sval != 0);
182		break;
183
184	case 8:
185		do {
186			*--cp = to_char(val & 7);
187			val >>= 3;
188		} while (val);
189		if (octzero && *cp != '0')
190			*--cp = '0';
191		break;
192
193	case 16:
194		do {
195			*--cp = xdigs[val & 15];
196			val >>= 4;
197		} while (val);
198		break;
199
200	default:			/* oops */
201		abort();
202	}
203	return (cp);
204}
205
206/* Identical to __ultoa, but for quads. */
207static char *
208__uqtoa(val, endp, base, octzero, xdigs)
209	register u_quad_t val;
210	char *endp;
211	int base, octzero;
212	char *xdigs;
213{
214	register char *cp = endp;
215	register quad_t sval;
216
217	/* quick test for small values; __ultoa is typically much faster */
218	/* (perhaps instead we should run until small, then call __ultoa?) */
219	if (val <= ULONG_MAX)
220		return (__ultoa((u_long)val, endp, base, octzero, xdigs));
221	switch (base) {
222	case 10:
223		if (val < 10) {
224			*--cp = to_char(val % 10);
225			return (cp);
226		}
227		if (val > QUAD_MAX) {
228			*--cp = to_char(val % 10);
229			sval = val / 10;
230		} else
231			sval = val;
232		do {
233			*--cp = to_char(sval % 10);
234			sval /= 10;
235		} while (sval != 0);
236		break;
237
238	case 8:
239		do {
240			*--cp = to_char(val & 7);
241			val >>= 3;
242		} while (val);
243		if (octzero && *cp != '0')
244			*--cp = '0';
245		break;
246
247	case 16:
248		do {
249			*--cp = xdigs[val & 15];
250			val >>= 4;
251		} while (val);
252		break;
253
254	default:
255		abort();
256	}
257	return (cp);
258}
259
260#ifdef FLOATING_POINT
261#include <math.h>
262#include "floatio.h"
263
264#define	BUF		(MAXEXP+MAXFRACT+1)	/* + decimal point */
265#define	DEFPREC		6
266
267static char *cvt __P((double, int, int, char *, int *, int, int *));
268static int exponent __P((char *, int, int));
269
270#else /* no FLOATING_POINT */
271
272#define	BUF		68
273
274#endif /* FLOATING_POINT */
275
276#define STATIC_ARG_TBL_SIZE 8           /* Size of static argument table. */
277
278/*
279 * Flags used during conversion.
280 */
281#define	ALT		0x001		/* alternate form */
282#define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
283#define	LADJUST		0x004		/* left adjustment */
284#define	LONGDBL		0x008		/* long double */
285#define	LONGINT		0x010		/* long integer */
286#define	QUADINT		0x020		/* quad integer */
287#define	SHORTINT	0x040		/* short integer */
288#define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
289#define FPT		0x100		/* Floating point number */
290int
291vfprintf(fp, fmt0, ap)
292	FILE *fp;
293	const char *fmt0;
294	va_list ap;
295{
296	register char *fmt;	/* format string */
297	register int ch;	/* character from fmt */
298	register int n, n2;	/* handy integer (short term usage) */
299	register char *cp;	/* handy char pointer (short term usage) */
300	register struct __siov *iovp;/* for PRINT macro */
301	register int flags;	/* flags as above */
302	int ret;		/* return value accumulator */
303	int width;		/* width from format (%8d), or 0 */
304	int prec;		/* precision from format (%.3d), or -1 */
305	char sign;		/* sign prefix (' ', '+', '-', or \0) */
306#ifdef FLOATING_POINT
307	char softsign;		/* temporary negative sign for floats */
308	double _double;		/* double precision arguments %[eEfgG] */
309	int expt;		/* integer value of exponent */
310	int expsize;		/* character count for expstr */
311	int ndig;		/* actual number of digits returned by cvt */
312	char expstr[7];		/* buffer for exponent string */
313#endif
314	u_long	ulval;		/* integer arguments %[diouxX] */
315	u_quad_t uqval;		/* %q integers */
316	int base;		/* base for [diouxX] conversion */
317	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
318	int realsz;		/* field size expanded by dprec, sign, etc */
319	int size;		/* size of converted field or string */
320	int prsize;             /* max size of printed field */
321	char *xdigs;		/* digits for [xX] conversion */
322#define NIOV 8
323	struct __suio uio;	/* output information: summary */
324	struct __siov iov[NIOV];/* ... and individual io vectors */
325	char buf[BUF];		/* space for %c, %[diouxX], %[eEfgG] */
326	char ox[2];		/* space for 0x hex-prefix */
327        void **argtable;        /* args, built due to positional arg */
328        void *statargtable [STATIC_ARG_TBL_SIZE];
329        int nextarg;            /* 1-based argument index */
330        va_list orgap;          /* original argument pointer */
331
332	/*
333	 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
334	 * fields occur frequently, increase PADSIZE and make the initialisers
335	 * below longer.
336	 */
337#define	PADSIZE	16		/* pad chunk size */
338	static char blanks[PADSIZE] =
339	 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
340	static char zeroes[PADSIZE] =
341	 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
342
343	/*
344	 * BEWARE, these `goto error' on error, and PAD uses `n'.
345	 */
346#define	PRINT(ptr, len) { \
347	iovp->iov_base = (ptr); \
348	iovp->iov_len = (len); \
349	uio.uio_resid += (len); \
350	iovp++; \
351	if (++uio.uio_iovcnt >= NIOV) { \
352		if (__sprint(fp, &uio)) \
353			goto error; \
354		iovp = iov; \
355	} \
356}
357#define	PAD(howmany, with) { \
358	if ((n = (howmany)) > 0) { \
359		while (n > PADSIZE) { \
360			PRINT(with, PADSIZE); \
361			n -= PADSIZE; \
362		} \
363		PRINT(with, n); \
364	} \
365}
366#define	FLUSH() { \
367	if (uio.uio_resid && __sprint(fp, &uio)) \
368		goto error; \
369	uio.uio_iovcnt = 0; \
370	iovp = iov; \
371}
372
373        /*
374         * Get the argument indexed by nextarg.   If the argument table is
375         * built, use it to get the argument.  If its not, get the next
376         * argument (and arguments must be gotten sequentially).
377         */
378#define GETARG(type) \
379        ((argtable != NULL) ? *((type*)(argtable[nextarg++])) : \
380            (nextarg++, va_arg(ap, type)))
381
382	/*
383	 * To extend shorts properly, we need both signed and unsigned
384	 * argument extraction methods.
385	 */
386#define	SARG() \
387	(flags&LONGINT ? GETARG(long) : \
388	    flags&SHORTINT ? (long)(short)GETARG(int) : \
389	    (long)GETARG(int))
390#define	UARG() \
391	(flags&LONGINT ? GETARG(u_long) : \
392	    flags&SHORTINT ? (u_long)(u_short)GETARG(int) : \
393	    (u_long)GETARG(u_int))
394
395        /*
396         * Get * arguments, including the form *nn$.  Preserve the nextarg
397         * that the argument can be gotten once the type is determined.
398         */
399#define GETASTER(val) \
400        n2 = 0; \
401        cp = fmt; \
402        while (is_digit(*cp)) { \
403                n2 = 10 * n2 + to_digit(*cp); \
404                cp++; \
405        } \
406        if (*cp == '$') { \
407            	int hold = nextarg; \
408                if (argtable == NULL) { \
409                        argtable = statargtable; \
410                        __find_arguments (fmt0, orgap, &argtable); \
411                } \
412                nextarg = n2; \
413                val = GETARG (int); \
414                nextarg = hold; \
415                fmt = ++cp; \
416        } else { \
417		val = GETARG (int); \
418        }
419
420
421	FLOCKFILE(fp);
422	/* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
423	if (cantwrite(fp)) {
424		FUNLOCKFILE(fp);
425		return (EOF);
426	}
427
428	/* optimise fprintf(stderr) (and other unbuffered Unix files) */
429	if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
430	    fp->_file >= 0) {
431		FUNLOCKFILE(fp);
432		return (__sbprintf(fp, fmt0, ap));
433	}
434
435	fmt = (char *)fmt0;
436        argtable = NULL;
437        nextarg = 1;
438        orgap = ap;
439	uio.uio_iov = iovp = iov;
440	uio.uio_resid = 0;
441	uio.uio_iovcnt = 0;
442	ret = 0;
443
444	/*
445	 * Scan the format for conversions (`%' character).
446	 */
447	for (;;) {
448		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
449			/* void */;
450		if ((n = fmt - cp) != 0) {
451			if ((unsigned)ret + n > INT_MAX) {
452				ret = EOF;
453				goto error;
454			}
455			PRINT(cp, n);
456			ret += n;
457		}
458		if (ch == '\0')
459			goto done;
460		fmt++;		/* skip over '%' */
461
462		flags = 0;
463		dprec = 0;
464		width = 0;
465		prec = -1;
466		sign = '\0';
467
468rflag:		ch = *fmt++;
469reswitch:	switch (ch) {
470		case ' ':
471			/*
472			 * ``If the space and + flags both appear, the space
473			 * flag will be ignored.''
474			 *	-- ANSI X3J11
475			 */
476			if (!sign)
477				sign = ' ';
478			goto rflag;
479		case '#':
480			flags |= ALT;
481			goto rflag;
482		case '*':
483			/*
484			 * ``A negative field width argument is taken as a
485			 * - flag followed by a positive field width.''
486			 *	-- ANSI X3J11
487			 * They don't exclude field widths read from args.
488			 */
489			GETASTER (width);
490			if (width >= 0)
491				goto rflag;
492			width = -width;
493			/* FALLTHROUGH */
494		case '-':
495			flags |= LADJUST;
496			goto rflag;
497		case '+':
498			sign = '+';
499			goto rflag;
500		case '.':
501			if ((ch = *fmt++) == '*') {
502				GETASTER (n);
503				prec = n < 0 ? -1 : n;
504				goto rflag;
505			}
506			n = 0;
507			while (is_digit(ch)) {
508				n = 10 * n + to_digit(ch);
509				ch = *fmt++;
510			}
511			prec = n < 0 ? -1 : n;
512			goto reswitch;
513		case '0':
514			/*
515			 * ``Note that 0 is taken as a flag, not as the
516			 * beginning of a field width.''
517			 *	-- ANSI X3J11
518			 */
519			flags |= ZEROPAD;
520			goto rflag;
521		case '1': case '2': case '3': case '4':
522		case '5': case '6': case '7': case '8': case '9':
523			n = 0;
524			do {
525				n = 10 * n + to_digit(ch);
526				ch = *fmt++;
527			} while (is_digit(ch));
528			if (ch == '$') {
529				nextarg = n;
530                        	if (argtable == NULL) {
531                                	argtable = statargtable;
532                                	__find_arguments (fmt0, orgap,
533						&argtable);
534				}
535				goto rflag;
536                        }
537			width = n;
538			goto reswitch;
539#ifdef FLOATING_POINT
540		case 'L':
541			flags |= LONGDBL;
542			goto rflag;
543#endif
544		case 'h':
545			flags |= SHORTINT;
546			goto rflag;
547		case 'l':
548			if (flags & LONGINT)
549				flags |= QUADINT;
550			else
551				flags |= LONGINT;
552			goto rflag;
553		case 'q':
554			flags |= QUADINT;
555			goto rflag;
556		case 'c':
557			*(cp = buf) = GETARG(int);
558			size = 1;
559			sign = '\0';
560			break;
561		case 'D':
562			flags |= LONGINT;
563			/*FALLTHROUGH*/
564		case 'd':
565		case 'i':
566			if (flags & QUADINT) {
567				uqval = GETARG(quad_t);
568				if ((quad_t)uqval < 0) {
569					uqval = -uqval;
570					sign = '-';
571				}
572			} else {
573				ulval = SARG();
574				if ((long)ulval < 0) {
575					ulval = -ulval;
576					sign = '-';
577				}
578			}
579			base = 10;
580			goto number;
581#ifdef FLOATING_POINT
582		case 'e':
583		case 'E':
584		case 'f':
585			goto fp_begin;
586		case 'g':
587		case 'G':
588			if (prec == 0)
589				prec = 1;
590fp_begin:		if (prec == -1)
591				prec = DEFPREC;
592			if (flags & LONGDBL)
593				/* XXX this loses precision. */
594				_double = (double)GETARG(long double);
595			else
596				_double = GETARG(double);
597			/* do this before tricky precision changes */
598			if (isinf(_double)) {
599				if (_double < 0)
600					sign = '-';
601				cp = "Inf";
602				size = 3;
603				break;
604			}
605			if (isnan(_double)) {
606				cp = "NaN";
607				size = 3;
608				break;
609			}
610			flags |= FPT;
611			cp = cvt(_double, prec, flags, &softsign,
612				&expt, ch, &ndig);
613			if (ch == 'g' || ch == 'G') {
614				if (expt <= -4 || expt > prec)
615					ch = (ch == 'g') ? 'e' : 'E';
616				else
617					ch = 'g';
618			}
619			if (ch <= 'e') {	/* 'e' or 'E' fmt */
620				--expt;
621				expsize = exponent(expstr, expt, ch);
622				size = expsize + ndig;
623				if (ndig > 1 || flags & ALT)
624					++size;
625			} else if (ch == 'f') {		/* f fmt */
626				if (expt > 0) {
627					size = expt;
628					if (prec || flags & ALT)
629						size += prec + 1;
630				} else	/* "0.X" */
631					size = prec + 2;
632			} else if (expt >= ndig) {	/* fixed g fmt */
633				size = expt;
634				if (flags & ALT)
635					++size;
636			} else
637				size = ndig + (expt > 0 ?
638					1 : 2 - expt);
639
640			if (softsign)
641				sign = '-';
642			break;
643#endif /* FLOATING_POINT */
644		case 'n':
645			if (flags & QUADINT)
646				*GETARG(quad_t *) = ret;
647			else if (flags & LONGINT)
648				*GETARG(long *) = ret;
649			else if (flags & SHORTINT)
650				*GETARG(short *) = ret;
651			else
652				*GETARG(int *) = ret;
653			continue;	/* no output */
654		case 'O':
655			flags |= LONGINT;
656			/*FALLTHROUGH*/
657		case 'o':
658			if (flags & QUADINT)
659				uqval = GETARG(u_quad_t);
660			else
661				ulval = UARG();
662			base = 8;
663			goto nosign;
664		case 'p':
665			/*
666			 * ``The argument shall be a pointer to void.  The
667			 * value of the pointer is converted to a sequence
668			 * of printable characters, in an implementation-
669			 * defined manner.''
670			 *	-- ANSI X3J11
671			 */
672			ulval = (u_long)GETARG(void *);
673			base = 16;
674			xdigs = "0123456789abcdef";
675			flags = (flags & ~QUADINT) | HEXPREFIX;
676			ch = 'x';
677			goto nosign;
678		case 's':
679			if ((cp = GETARG(char *)) == NULL)
680				cp = "(null)";
681			if (prec >= 0) {
682				/*
683				 * can't use strlen; can only look for the
684				 * NUL in the first `prec' characters, and
685				 * strlen() will go further.
686				 */
687				char *p = memchr(cp, 0, (size_t)prec);
688
689				if (p != NULL) {
690					size = p - cp;
691					if (size > prec)
692						size = prec;
693				} else
694					size = prec;
695			} else
696				size = strlen(cp);
697			sign = '\0';
698			break;
699		case 'U':
700			flags |= LONGINT;
701			/*FALLTHROUGH*/
702		case 'u':
703			if (flags & QUADINT)
704				uqval = GETARG(u_quad_t);
705			else
706				ulval = UARG();
707			base = 10;
708			goto nosign;
709		case 'X':
710			xdigs = "0123456789ABCDEF";
711			goto hex;
712		case 'x':
713			xdigs = "0123456789abcdef";
714hex:			if (flags & QUADINT)
715				uqval = GETARG(u_quad_t);
716			else
717				ulval = UARG();
718			base = 16;
719			/* leading 0x/X only if non-zero */
720			if (flags & ALT &&
721			    (flags & QUADINT ? uqval != 0 : ulval != 0))
722				flags |= HEXPREFIX;
723
724			/* unsigned conversions */
725nosign:			sign = '\0';
726			/*
727			 * ``... diouXx conversions ... if a precision is
728			 * specified, the 0 flag will be ignored.''
729			 *	-- ANSI X3J11
730			 */
731number:			if ((dprec = prec) >= 0)
732				flags &= ~ZEROPAD;
733
734			/*
735			 * ``The result of converting a zero value with an
736			 * explicit precision of zero is no characters.''
737			 *	-- ANSI X3J11
738			 */
739			cp = buf + BUF;
740			if (flags & QUADINT) {
741				if (uqval != 0 || prec != 0)
742					cp = __uqtoa(uqval, cp, base,
743					    flags & ALT, xdigs);
744			} else {
745				if (ulval != 0 || prec != 0)
746					cp = __ultoa(ulval, cp, base,
747					    flags & ALT, xdigs);
748			}
749			size = buf + BUF - cp;
750			break;
751		default:	/* "%?" prints ?, unless ? is NUL */
752			if (ch == '\0')
753				goto done;
754			/* pretend it was %c with argument ch */
755			cp = buf;
756			*cp = ch;
757			size = 1;
758			sign = '\0';
759			break;
760		}
761
762		/*
763		 * All reasonable formats wind up here.  At this point, `cp'
764		 * points to a string which (if not flags&LADJUST) should be
765		 * padded out to `width' places.  If flags&ZEROPAD, it should
766		 * first be prefixed by any sign or other prefix; otherwise,
767		 * it should be blank padded before the prefix is emitted.
768		 * After any left-hand padding and prefixing, emit zeroes
769		 * required by a decimal [diouxX] precision, then print the
770		 * string proper, then emit zeroes required by any leftover
771		 * floating precision; finally, if LADJUST, pad with blanks.
772		 *
773		 * Compute actual size, so we know how much to pad.
774		 * size excludes decimal prec; realsz includes it.
775		 */
776		realsz = dprec > size ? dprec : size;
777		if (sign)
778			realsz++;
779		else if (flags & HEXPREFIX)
780			realsz += 2;
781
782		prsize = width > realsz ? width : realsz;
783		if ((unsigned)ret + prsize > INT_MAX) {
784			ret = EOF;
785			goto error;
786		}
787
788		/* right-adjusting blank padding */
789		if ((flags & (LADJUST|ZEROPAD)) == 0)
790			PAD(width - realsz, blanks);
791
792		/* prefix */
793		if (sign) {
794			PRINT(&sign, 1);
795		} else if (flags & HEXPREFIX) {
796			ox[0] = '0';
797			ox[1] = ch;
798			PRINT(ox, 2);
799		}
800
801		/* right-adjusting zero padding */
802		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
803			PAD(width - realsz, zeroes);
804
805		/* leading zeroes from decimal precision */
806		PAD(dprec - size, zeroes);
807
808		/* the string or number proper */
809#ifdef FLOATING_POINT
810		if ((flags & FPT) == 0) {
811			PRINT(cp, size);
812		} else {	/* glue together f_p fragments */
813			if (ch >= 'f') {	/* 'f' or 'g' */
814				if (_double == 0) {
815					/* kludge for __dtoa irregularity */
816					if (expt >= ndig &&
817					    (flags & ALT) == 0) {
818						PRINT("0", 1);
819					} else {
820						PRINT("0.", 2);
821						PAD(ndig - 1, zeroes);
822					}
823				} else if (expt <= 0) {
824					PRINT("0.", 2);
825					PAD(-expt, zeroes);
826					PRINT(cp, ndig);
827				} else if (expt >= ndig) {
828					PRINT(cp, ndig);
829					PAD(expt - ndig, zeroes);
830					if (flags & ALT)
831						PRINT(".", 1);
832				} else {
833					PRINT(cp, expt);
834					cp += expt;
835					PRINT(".", 1);
836					PRINT(cp, ndig-expt);
837				}
838			} else {	/* 'e' or 'E' */
839				if (ndig > 1 || flags & ALT) {
840					ox[0] = *cp++;
841					ox[1] = '.';
842					PRINT(ox, 2);
843					if (_double) {
844						PRINT(cp, ndig-1);
845					} else	/* 0.[0..] */
846						/* __dtoa irregularity */
847						PAD(ndig - 1, zeroes);
848				} else	/* XeYYY */
849					PRINT(cp, 1);
850				PRINT(expstr, expsize);
851			}
852		}
853#else
854		PRINT(cp, size);
855#endif
856		/* left-adjusting padding (always blank) */
857		if (flags & LADJUST)
858			PAD(width - realsz, blanks);
859
860		/* finally, adjust ret */
861		ret += prsize;
862
863		FLUSH();	/* copy out the I/O vectors */
864	}
865done:
866	FLUSH();
867error:
868	if (__sferror(fp))
869		ret = EOF;
870	FUNLOCKFILE(fp);
871        if ((argtable != NULL) && (argtable != statargtable))
872                free (argtable);
873	return (ret);
874	/* NOTREACHED */
875}
876
877/*
878 * Type ids for argument type table.
879 */
880#define T_UNUSED	0
881#define T_SHORT		1
882#define T_U_SHORT	2
883#define TP_SHORT	3
884#define T_INT		4
885#define T_U_INT		5
886#define TP_INT		6
887#define T_LONG		7
888#define T_U_LONG	8
889#define TP_LONG		9
890#define T_QUAD		10
891#define T_U_QUAD	11
892#define TP_QUAD		12
893#define T_DOUBLE	13
894#define T_LONG_DOUBLE	14
895#define TP_CHAR		15
896#define TP_VOID		16
897
898/*
899 * Find all arguments when a positional parameter is encountered.  Returns a
900 * table, indexed by argument number, of pointers to each arguments.  The
901 * initial argument table should be an array of STATIC_ARG_TBL_SIZE entries.
902 * It will be replaces with a malloc-ed one if it overflows.
903 */
904static void
905__find_arguments (fmt0, ap, argtable)
906	const char *fmt0;
907	va_list ap;
908	void ***argtable;
909{
910	register char *fmt;	/* format string */
911	register int ch;	/* character from fmt */
912	register int n, n2;	/* handy integer (short term usage) */
913	register char *cp;	/* handy char pointer (short term usage) */
914	register int flags;	/* flags as above */
915	int width;		/* width from format (%8d), or 0 */
916	unsigned char *typetable; /* table of types */
917	unsigned char stattypetable [STATIC_ARG_TBL_SIZE];
918	int tablesize;		/* current size of type table */
919	int tablemax;		/* largest used index in table */
920	int nextarg;		/* 1-based argument index */
921
922	/*
923	 * Add an argument type to the table, expanding if necessary.
924	 */
925#define ADDTYPE(type) \
926	((nextarg >= tablesize) ? \
927		__grow_type_table(nextarg, &typetable, &tablesize) : 0, \
928	(nextarg > tablemax) ? tablemax = nextarg : 0, \
929	typetable[nextarg++] = type)
930
931#define	ADDSARG() \
932	((flags&LONGINT) ? ADDTYPE(T_LONG) : \
933		((flags&SHORTINT) ? ADDTYPE(T_SHORT) : ADDTYPE(T_INT)))
934
935#define	ADDUARG() \
936	((flags&LONGINT) ? ADDTYPE(T_U_LONG) : \
937		((flags&SHORTINT) ? ADDTYPE(T_U_SHORT) : ADDTYPE(T_U_INT)))
938
939	/*
940	 * Add * arguments to the type array.
941	 */
942#define ADDASTER() \
943	n2 = 0; \
944	cp = fmt; \
945	while (is_digit(*cp)) { \
946		n2 = 10 * n2 + to_digit(*cp); \
947		cp++; \
948	} \
949	if (*cp == '$') { \
950		int hold = nextarg; \
951		nextarg = n2; \
952		ADDTYPE (T_INT); \
953		nextarg = hold; \
954		fmt = ++cp; \
955	} else { \
956		ADDTYPE (T_INT); \
957	}
958	fmt = (char *)fmt0;
959	typetable = stattypetable;
960	tablesize = STATIC_ARG_TBL_SIZE;
961	tablemax = 0;
962	nextarg = 1;
963	memset (typetable, T_UNUSED, STATIC_ARG_TBL_SIZE);
964
965	/*
966	 * Scan the format for conversions (`%' character).
967	 */
968	for (;;) {
969		for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
970			/* void */;
971		if (ch == '\0')
972			goto done;
973		fmt++;		/* skip over '%' */
974
975		flags = 0;
976		width = 0;
977
978rflag:		ch = *fmt++;
979reswitch:	switch (ch) {
980		case ' ':
981		case '#':
982			goto rflag;
983		case '*':
984			ADDASTER ();
985			goto rflag;
986		case '-':
987		case '+':
988			goto rflag;
989		case '.':
990			if ((ch = *fmt++) == '*') {
991				ADDASTER ();
992				goto rflag;
993			}
994			while (is_digit(ch)) {
995				ch = *fmt++;
996			}
997			goto reswitch;
998		case '0':
999			goto rflag;
1000		case '1': case '2': case '3': case '4':
1001		case '5': case '6': case '7': case '8': case '9':
1002			n = 0;
1003			do {
1004				n = 10 * n + to_digit(ch);
1005				ch = *fmt++;
1006			} while (is_digit(ch));
1007			if (ch == '$') {
1008				nextarg = n;
1009				goto rflag;
1010			}
1011			width = n;
1012			goto reswitch;
1013#ifdef FLOATING_POINT
1014		case 'L':
1015			flags |= LONGDBL;
1016			goto rflag;
1017#endif
1018		case 'h':
1019			flags |= SHORTINT;
1020			goto rflag;
1021		case 'l':
1022			if (flags & LONGINT)
1023				flags |= QUADINT;
1024			else
1025				flags |= LONGINT;
1026			goto rflag;
1027		case 'q':
1028			flags |= QUADINT;
1029			goto rflag;
1030		case 'c':
1031			ADDTYPE(T_INT);
1032			break;
1033		case 'D':
1034			flags |= LONGINT;
1035			/*FALLTHROUGH*/
1036		case 'd':
1037		case 'i':
1038			if (flags & QUADINT) {
1039				ADDTYPE(T_QUAD);
1040			} else {
1041				ADDSARG();
1042			}
1043			break;
1044#ifdef FLOATING_POINT
1045		case 'e':
1046		case 'E':
1047		case 'f':
1048		case 'g':
1049		case 'G':
1050			if (flags & LONGDBL)
1051				ADDTYPE(T_LONG_DOUBLE);
1052			else
1053				ADDTYPE(T_DOUBLE);
1054			break;
1055#endif /* FLOATING_POINT */
1056		case 'n':
1057			if (flags & QUADINT)
1058				ADDTYPE(TP_QUAD);
1059			else if (flags & LONGINT)
1060				ADDTYPE(TP_LONG);
1061			else if (flags & SHORTINT)
1062				ADDTYPE(TP_SHORT);
1063			else
1064				ADDTYPE(TP_INT);
1065			continue;	/* no output */
1066		case 'O':
1067			flags |= LONGINT;
1068			/*FALLTHROUGH*/
1069		case 'o':
1070			if (flags & QUADINT)
1071				ADDTYPE(T_U_QUAD);
1072			else
1073				ADDUARG();
1074			break;
1075		case 'p':
1076			ADDTYPE(TP_VOID);
1077			break;
1078		case 's':
1079			ADDTYPE(TP_CHAR);
1080			break;
1081		case 'U':
1082			flags |= LONGINT;
1083			/*FALLTHROUGH*/
1084		case 'u':
1085			if (flags & QUADINT)
1086				ADDTYPE(T_U_QUAD);
1087			else
1088				ADDUARG();
1089			break;
1090		case 'X':
1091		case 'x':
1092			if (flags & QUADINT)
1093				ADDTYPE(T_U_QUAD);
1094			else
1095				ADDUARG();
1096			break;
1097		default:	/* "%?" prints ?, unless ? is NUL */
1098			if (ch == '\0')
1099				goto done;
1100			break;
1101		}
1102	}
1103done:
1104	/*
1105	 * Build the argument table.
1106	 */
1107	if (tablemax >= STATIC_ARG_TBL_SIZE) {
1108		*argtable = (void **)
1109		    malloc (sizeof (void *) * (tablemax + 1));
1110	}
1111
1112	(*argtable) [0] = NULL;
1113	for (n = 1; n <= tablemax; n++) {
1114		switch (typetable [n]) {
1115		    case T_UNUSED:
1116			(*argtable) [n] = (void *) &va_arg (ap, int);
1117			break;
1118		    case T_SHORT:
1119			(*argtable) [n] = (void *) &va_arg (ap, int);
1120			break;
1121		    case T_U_SHORT:
1122			(*argtable) [n] = (void *) &va_arg (ap, int);
1123			break;
1124		    case TP_SHORT:
1125			(*argtable) [n] = (void *) &va_arg (ap, short *);
1126			break;
1127		    case T_INT:
1128			(*argtable) [n] = (void *) &va_arg (ap, int);
1129			break;
1130		    case T_U_INT:
1131			(*argtable) [n] = (void *) &va_arg (ap, unsigned int);
1132			break;
1133		    case TP_INT:
1134			(*argtable) [n] = (void *) &va_arg (ap, int *);
1135			break;
1136		    case T_LONG:
1137			(*argtable) [n] = (void *) &va_arg (ap, long);
1138			break;
1139		    case T_U_LONG:
1140			(*argtable) [n] = (void *) &va_arg (ap, unsigned long);
1141			break;
1142		    case TP_LONG:
1143			(*argtable) [n] = (void *) &va_arg (ap, long *);
1144			break;
1145		    case T_QUAD:
1146			(*argtable) [n] = (void *) &va_arg (ap, quad_t);
1147			break;
1148		    case T_U_QUAD:
1149			(*argtable) [n] = (void *) &va_arg (ap, u_quad_t);
1150			break;
1151		    case TP_QUAD:
1152			(*argtable) [n] = (void *) &va_arg (ap, quad_t *);
1153			break;
1154		    case T_DOUBLE:
1155			(*argtable) [n] = (void *) &va_arg (ap, double);
1156			break;
1157		    case T_LONG_DOUBLE:
1158			(*argtable) [n] = (void *) &va_arg (ap, long double);
1159			break;
1160		    case TP_CHAR:
1161			(*argtable) [n] = (void *) &va_arg (ap, char *);
1162			break;
1163		    case TP_VOID:
1164			(*argtable) [n] = (void *) &va_arg (ap, void *);
1165			break;
1166		}
1167	}
1168
1169	if ((typetable != NULL) && (typetable != stattypetable))
1170		free (typetable);
1171}
1172
1173/*
1174 * Increase the size of the type table.
1175 */
1176static void
1177__grow_type_table (nextarg, typetable, tablesize)
1178	int nextarg;
1179	unsigned char **typetable;
1180	int *tablesize;
1181{
1182	unsigned char *const oldtable = *typetable;
1183	const int oldsize = *tablesize;
1184	unsigned char *newtable;
1185	int newsize = oldsize * 2;
1186
1187	if (newsize < nextarg + 1)
1188		newsize = nextarg + 1;
1189	if (oldsize == STATIC_ARG_TBL_SIZE) {
1190		if ((newtable = malloc(newsize)) == NULL)
1191			abort();			/* XXX handle better */
1192		bcopy(oldtable, newtable, oldsize);
1193	} else {
1194		if ((newtable = reallocf(oldtable, newsize)) == NULL)
1195			abort();			/* XXX handle better */
1196	}
1197	memset(&newtable[oldsize], T_UNUSED, newsize - oldsize);
1198
1199	*typetable = newtable;
1200	*tablesize = newsize;
1201}
1202
1203
1204#ifdef FLOATING_POINT
1205
1206extern char *__dtoa __P((double, int, int, int *, int *, char **));
1207
1208static char *
1209cvt(value, ndigits, flags, sign, decpt, ch, length)
1210	double value;
1211	int ndigits, flags, *decpt, ch, *length;
1212	char *sign;
1213{
1214	int mode, dsgn;
1215	char *digits, *bp, *rve;
1216
1217	if (ch == 'f')
1218		mode = 3;		/* ndigits after the decimal point */
1219	else {
1220		/*
1221		 * To obtain ndigits after the decimal point for the 'e'
1222		 * and 'E' formats, round to ndigits + 1 significant
1223		 * figures.
1224		 */
1225		if (ch == 'e' || ch == 'E')
1226			ndigits++;
1227		mode = 2;		/* ndigits significant digits */
1228	}
1229	if (value < 0) {
1230		value = -value;
1231		*sign = '-';
1232	} else
1233		*sign = '\000';
1234	digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
1235	if ((ch != 'g' && ch != 'G') || flags & ALT) {
1236		/* print trailing zeros */
1237		bp = digits + ndigits;
1238		if (ch == 'f') {
1239			if (*digits == '0' && value)
1240				*decpt = -ndigits + 1;
1241			bp += *decpt;
1242		}
1243		if (value == 0)	/* kludge for __dtoa irregularity */
1244			rve = bp;
1245		while (rve < bp)
1246			*rve++ = '0';
1247	}
1248	*length = rve - digits;
1249	return (digits);
1250}
1251
1252static int
1253exponent(p0, exp, fmtch)
1254	char *p0;
1255	int exp, fmtch;
1256{
1257	register char *p, *t;
1258	char expbuf[MAXEXP];
1259
1260	p = p0;
1261	*p++ = fmtch;
1262	if (exp < 0) {
1263		exp = -exp;
1264		*p++ = '-';
1265	}
1266	else
1267		*p++ = '+';
1268	t = expbuf + MAXEXP;
1269	if (exp > 9) {
1270		do {
1271			*--t = to_char(exp % 10);
1272		} while ((exp /= 10) > 9);
1273		*--t = to_char(exp);
1274		for (; t < expbuf + MAXEXP; *p++ = *t++);
1275	}
1276	else {
1277		*p++ = '0';
1278		*p++ = to_char(exp);
1279	}
1280	return (p - p0);
1281}
1282#endif /* FLOATING_POINT */
1283