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/*
FUNCTION
<<vprintf>>, <<vfprintf>>, <<vsprintf>>---format argument list
 
INDEX
	vprintf
INDEX
	vfprintf
INDEX
	vsprintf
INDEX
	vsnprintf
 
ANSI_SYNOPSIS
	#include <stdio.h>
	#include <stdarg.h>
	int vprintf(const char *<[fmt]>, va_list <[list]>);
	int vfprintf(FILE *<[fp]>, const char *<[fmt]>, va_list <[list]>);
	int vsprintf(char *<[str]>, const char *<[fmt]>, va_list <[list]>);
	int vsnprintf(char *<[str]>, size_t <[size]>, const char *<[fmt]>, va_list <[list]>);
 
	int _vprintf_r(void *<[reent]>, const char *<[fmt]>,
                        va_list <[list]>);
	int _vfprintf_r(void *<[reent]>, FILE *<[fp]>, const char *<[fmt]>,
                        va_list <[list]>);
	int _vsprintf_r(void *<[reent]>, char *<[str]>, const char *<[fmt]>,
                        va_list <[list]>);
	int _vsnprintf_r(void *<[reent]>, char *<[str]>, size_t <[size]>, const char *<[fmt]>,
                        va_list <[list]>);
 
TRAD_SYNOPSIS
	#include <stdio.h>
	#include <varargs.h>
	int vprintf( <[fmt]>, <[list]>)
	char *<[fmt]>;
	va_list <[list]>;
 
	int vfprintf(<[fp]>, <[fmt]>, <[list]>)
	FILE *<[fp]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int vsprintf(<[str]>, <[fmt]>, <[list]>)
	char *<[str]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int vsnprintf(<[str]>, <[size]>, <[fmt]>, <[list]>)
	char *<[str]>;
        size_t <[size]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int _vprintf_r(<[reent]>, <[fmt]>, <[list]>)
	char *<[reent]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int _vfprintf_r(<[reent]>, <[fp]>, <[fmt]>, <[list]>)
	char *<[reent]>;
	FILE *<[fp]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int _vsprintf_r(<[reent]>, <[str]>, <[fmt]>, <[list]>)
	char *<[reent]>;
	char *<[str]>;
	char *<[fmt]>;
	va_list <[list]>;
 
	int _vsnprintf_r(<[reent]>, <[str]>, <[size]>, <[fmt]>, <[list]>)
	char *<[reent]>;
	char *<[str]>;
        size_t <[size]>;
	char *<[fmt]>;
	va_list <[list]>;
 
DESCRIPTION
<<vprintf>>, <<vfprintf>>, <<vsprintf>> and <<vsnprintf>> are (respectively)
variants of <<printf>>, <<fprintf>>, <<sprintf>> and <<snprintf>>.  They differ
only in allowing their caller to pass the variable argument list as a
<<va_list>> object (initialized by <<va_start>>) rather than directly
accepting a variable number of arguments.
 
RETURNS
The return values are consistent with the corresponding functions:
<<vsprintf>> returns the number of bytes in the output string,
save that the concluding <<NULL>> is not counted.
<<vprintf>> and <<vfprintf>> return the number of characters transmitted.
If an error occurs, <<vprintf>> and <<vfprintf>> return <<EOF>>. No
error returns occur for <<vsprintf>>.
 
PORTABILITY
ANSI C requires all three functions.
 
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
 
/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#define INTEGER_ONLY
#define _HAVE_STDC_
#define u_long unsigned long
#define u_short unsigned short
#define u_int unsigned int
#define _uquad_t u_long
#define _POINTER_INT int
#define _CONST const
#define NULL 0
 
#include "common.h"
#include "support.h"
 
#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)vfprintf.c	5.50 (Berkeley) 12/16/92";*/
static char *rcsid = "$Id: cprintf.c,v 1.1.1.1 2002-04-11 10:47:29 simons Exp $";
#endif /* LIBC_SCCS and not lint */
 
/*
 * Actual printf innards.
 *
 * This code is large and complicated...
 */
 
#ifdef INTEGER_ONLY
#define VFPRINTF vfiprintf
#define _VFPRINTF_R _vfiprintf_r
#else
#define VFPRINTF vfprintf
#define _VFPRINTF_R _vfprintf_r
#define FLOATING_POINT
#endif
 
#define _NO_LONGLONG
#if defined WANT_PRINTF_LONG_LONG && defined __GNUC__
# undef _NO_LONGLONG
#endif
 
#include <stdarg.h>
 
#ifdef FLOATING_POINT
#include <locale.h>
#include <math.h>
#include "floatio.h"
 
#define	BUF		(MAXEXP+MAXFRACT+1)	/* + decimal point */
#define	DEFPREC		6
 
static char *cvt _PARAMS((struct _reent *, double, int, int, char *, int *, int, int *));
static int exponent _PARAMS((char *, int, int));
 
#else /* no FLOATING_POINT */
 
#define	BUF		40
 
#endif /* FLOATING_POINT */
 
/*
 * Macros for converting digits to letters and vice versa
 */
#define	to_digit(c)	((c) - '0')
#define is_digit(c)	((unsigned)to_digit(c) <= 9)
#define	to_char(n)	((n) + '0')
 
/*
 * Flags used during conversion.
 */
#define	ALT		0x001		/* alternate form */
#define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
#define	LADJUST		0x004		/* left adjustment */
#define	LONGDBL		0x008		/* long double; unimplemented */
#define	LONGINT		0x010		/* long integer */
#define	QUADINT		0x020		/* quad integer */
#define	SHORTINT	0x040		/* short integer */
#define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
#define FPT		0x100		/* Floating point number */
 
	/*
	 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
	 * fields occur frequently, increase PADSIZE and make the initialisers
	 * below longer.
	 */
#define	PADSIZE	16		/* pad chunk size */
	static _CONST char blanks[PADSIZE] =
	 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
	static _CONST char zeroes[PADSIZE] =
	 {'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
 
inline void pc (_CONST char c) {
#ifdef OR1K
  putc (c);
#else
  printf ("%c", c);
#endif
}
	/*
	 * BEWARE, these `goto error' on error, and PAD uses `n'.
	 */
inline void	PRINT(_CONST char *ptr, int len) {
  int i;
  for (i = 0; i < len; i++)
	  pc(*(ptr++));
}
 
inline void PAD(int howmany, _CONST char *with) {
  int n;
	if ((n = howmany) > 0) {
		while (n > PADSIZE) {
			PRINT(with, PADSIZE);
			n -= PADSIZE;
		}
		PRINT(with, n);
	}
}
 
int printf(const char *fmt0,	...)
{  
	register char *fmt;	/* format string */
	register int ch;	/* character from fmt */
	int n;	/* handy integers (short term usage) */
	register char *cp;	/* handy char pointer (short term usage) */
	register int flags;	/* flags as above */
	int ret;		/* return value accumulator */
	int width;		/* width from format (%8d), or 0 */
	int prec;		/* precision from format (%.3d), or -1 */
	char sign;		/* sign prefix (' ', '+', '-', or \0) */
	va_list ap;
 
#ifdef FLOATING_POINT
	char *decimal_point = localeconv()->decimal_point;
	char softsign;		/* temporary negative sign for floats */
	/*
	 * Although it is natural to declare this double here, the 
	 * declaration causes gcc to save FP registers even when not
	 * printing an FP number.  This results in surprising use
	 * of FP registers to print integers or strings on at least the
	 * PowerPC.  A more proper solution would be to move FP printing
	 * to another file, but this does seem to work.
	 */
#if 0
	double _double;		/* double precision arguments %[eEfgG] */
#else
			        /* double precision arguments %[eEfgG] */
	union { int i; double d; } _double_ = {0};
#define _double (_double_.d)
#endif
	int expt;		/* integer value of exponent */
	int expsize;		/* character count for expstr */
	int ndig;		/* actual number of digits returned by cvt */
	char expstr[7];		/* buffer for exponent string */
#endif
 
#ifndef _NO_LONGLONG
#define	quad_t	  long long
#define	u_quad_t  unsigned long long
#endif
 
#ifndef _NO_LONGLONG
	u_quad_t _uquad;	/* integer arguments %[diouxX] */
#else
	u_long _uquad;
#endif
	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
	int realsz;		/* field size expanded by dprec */
	int size;		/* size of converted field or string */
	char *xdigs = (char *)0;		/* digits for [xX] conversion */
#define NIOV 8
 
char buf[BUF];		/* space for %c, %[diouxX], %[eEfgG] */
char ox[2];		/* space for 0x hex-prefix */
 
#define	FLUSH()
 
	/*
	 * To extend shorts properly, we need both signed and unsigned
	 * argument extraction methods.
	 */
#ifndef _NO_LONGLONG
#define	SARG() \
	(flags&QUADINT ? va_arg(ap, quad_t) : \
	    flags&LONGINT ? va_arg(ap, long) : \
	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
	    (long)va_arg(ap, int))
#define	UARG() \
	(flags&QUADINT ? va_arg(ap, u_quad_t) : \
	    flags&LONGINT ? va_arg(ap, u_long) : \
	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
	    (u_long)va_arg(ap, u_int))
#else
#define	SARG() \
	(flags&LONGINT ? va_arg(ap, long) : \
	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
	    (long)va_arg(ap, int))
#define	UARG() \
	(flags&LONGINT ? va_arg(ap, u_long) : \
	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
	    (u_long)va_arg(ap, u_int))
#endif
 
  va_start (ap, fmt0);
	fmt = (char *)fmt0;
	ret = 0;
 
	/*
	 * Scan the format for conversions (`%' character).
	 */
	for (;;) {
 
	  while (*fmt != 0 && *fmt != '%') {
	    pc (*fmt);
      fmt++;
      ret++;
    }
		if (!*fmt)
			goto done;		
 
    fmt++; /* Skip % */
		flags = 0;
		dprec = 0;
		width = 0;
		prec = -1;
		sign = '\0';
 
rflag:		ch = *fmt++;
reswitch:	switch (ch) {
		case ' ':
			/*
			 * ``If the space and + flags both appear, the space
			 * flag will be ignored.''
			 *	-- ANSI X3J11
			 */
			if (!sign)
				sign = ' ';
			goto rflag;
		case '#':
			flags |= ALT;
			goto rflag;
		case '*':
			/*
			 * ``A negative field width argument is taken as a
			 * - flag followed by a positive field width.''
			 *	-- ANSI X3J11
			 * They don't exclude field widths read from args.
			 */
			if ((width = va_arg(ap, int)) >= 0)
				goto rflag;
			width = -width;
			/* FALLTHROUGH */
		case '-':
			flags |= LADJUST;
			goto rflag;
		case '+':
			sign = '+';
			goto rflag;
		case '.':
			if ((ch = *fmt++) == '*') {
				n = va_arg(ap, int);
				prec = n < 0 ? -1 : n;
				goto rflag;
			}
			n = 0;
			while (is_digit(ch)) {
				n = 10 * n + to_digit(ch);
				ch = *fmt++;
			}
			prec = n < 0 ? -1 : n;
			goto reswitch;
		case '0':
			/*
			 * ``Note that 0 is taken as a flag, not as the
			 * beginning of a field width.''
			 *	-- ANSI X3J11
			 */
			flags |= ZEROPAD;
			goto rflag;
		case '1': case '2': case '3': case '4':
		case '5': case '6': case '7': case '8': case '9':
			n = 0;
			do {
				n = 10 * n + to_digit(ch);
				ch = *fmt++;
			} while (is_digit(ch));
			width = n;
			goto reswitch;
#ifdef FLOATING_POINT
		case 'L':
			flags |= LONGDBL;
			goto rflag;
#endif
		case 'h':
			flags |= SHORTINT;
			goto rflag;
		case 'l':
			if (*fmt == 'l') {
				fmt++;
				flags |= QUADINT;
			} else {
				flags |= LONGINT;
			}
			goto rflag;
		case 'q':
			flags |= QUADINT;
			goto rflag;
		case 'c':
			*(cp = buf) = va_arg(ap, int);
			size = 1;
			sign = '\0';
			break;
		case 'D':
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'd':
		case 'i':
			_uquad = SARG();
#ifndef _NO_LONGLONG
			if ((quad_t)_uquad < 0)
#else
			if ((long) _uquad < 0)
#endif
			{
 
				_uquad = -_uquad;
				sign = '-';
			}
			base = DEC;
			goto number;
#ifdef FLOATING_POINT
		case 'e':
		case 'E':
		case 'f':
		case 'g':
		case 'G':
			if (prec == -1) {
				prec = DEFPREC;
			} else if ((ch == 'g' || ch == 'G') && prec == 0) {
				prec = 1;
			}
 
			if (flags & LONGDBL) {
				_double = (double) va_arg(ap, long double);
			} else {
				_double = va_arg(ap, double);
			}
 
			/* do this before tricky precision changes */
			if (isinf(_double)) {
				if (_double < 0)
					sign = '-';
				cp = "Inf";
				size = 3;
				break;
			}
			if (isnan(_double)) {
				cp = "NaN";
				size = 3;
				break;
			}
 
			flags |= FPT;
			cp = cvt(data, _double, prec, flags, &softsign,
				&expt, ch, &ndig);
			if (ch == 'g' || ch == 'G') {
				if (expt <= -4 || expt > prec)
					ch = (ch == 'g') ? 'e' : 'E';
				else
					ch = 'g';
			} 
			if (ch <= 'e') {	/* 'e' or 'E' fmt */
				--expt;
				expsize = exponent(expstr, expt, ch);
				size = expsize + ndig;
				if (ndig > 1 || flags & ALT)
					++size;
			} else if (ch == 'f') {		/* f fmt */
				if (expt > 0) {
					size = expt;
					if (prec || flags & ALT)
						size += prec + 1;
				} else	/* "0.X" */
					size = prec + 2;
			} else if (expt >= ndig) {	/* fixed g fmt */
				size = expt;
				if (flags & ALT)
					++size;
			} else
				size = ndig + (expt > 0 ?
					1 : 2 - expt);
 
			if (softsign)
				sign = '-';
			break;
#endif /* FLOATING_POINT */
		case 'n':
#ifndef _NO_LONGLONG
			if (flags & QUADINT)
				*va_arg(ap, quad_t *) = ret;
			else 
#endif
			if (flags & LONGINT)
				*va_arg(ap, long *) = ret;
			else if (flags & SHORTINT)
				*va_arg(ap, short *) = ret;
			else
				*va_arg(ap, int *) = ret;
			continue;	/* no output */
		case 'O':
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'o':
			_uquad = UARG();
			base = OCT;
			goto nosign;
		case 'p':
			/*
			 * ``The argument shall be a pointer to void.  The
			 * value of the pointer is converted to a sequence
			 * of printable characters, in an implementation-
			 * defined manner.''
			 *	-- ANSI X3J11
			 */
			/* NOSTRICT */
			_uquad = (u_long)(unsigned _POINTER_INT)va_arg(ap, void *);
			base = HEX;
			xdigs = "0123456789abcdef";
			flags |= HEXPREFIX;
			ch = 'x';
			goto nosign;
		case 's':
			if ((cp = va_arg(ap, char *)) == NULL)
				cp = "(null)";
			if (prec >= 0) {
				/*
				 * can't use strlen; can only look for the
				 * NUL in the first `prec' characters, and
				 * strlen() will go further.
				 */
				char *p = (char *)memchr(cp, 0, prec);
 
				if (p != NULL) {
					size = p - cp;
					if (size > prec)
						size = prec;
				} else
					size = prec;
			} else
				size = strlen(cp);
			sign = '\0';
			break;
		case 'U':
			flags |= LONGINT;
			/*FALLTHROUGH*/
		case 'u':
			_uquad = UARG();
			base = DEC;
			goto nosign;
		case 'X':
			xdigs = "0123456789ABCDEF";
			goto hex;
		case 'x':
			xdigs = "0123456789abcdef";
hex:			_uquad = UARG();
			base = HEX;
			/* leading 0x/X only if non-zero */
			if (flags & ALT && _uquad != 0)
				flags |= HEXPREFIX;
 
			/* unsigned conversions */
nosign:			sign = '\0';
			/*
			 * ``... diouXx conversions ... if a precision is
			 * specified, the 0 flag will be ignored.''
			 *	-- ANSI X3J11
			 */
number:			if ((dprec = prec) >= 0)
				flags &= ~ZEROPAD;
 
			/*
			 * ``The result of converting a zero value with an
			 * explicit precision of zero is no characters.''
			 *	-- ANSI X3J11
			 */
			cp = buf + BUF;
			if (_uquad != 0 || prec != 0) {
				/*
				 * Unsigned mod is hard, and unsigned mod
				 * by a constant is easier than that by
				 * a variable; hence this switch.
				 */
				switch (base) {
				case OCT:
					do {
						*--cp = to_char(_uquad & 7);
						_uquad >>= 3;
					} while (_uquad);
					/* handle octal leading 0 */
					if (flags & ALT && *cp != '0')
						*--cp = '0';
					break;
 
				case DEC:
					/* many numbers are 1 digit */
					while (_uquad >= 10) {
						*--cp = to_char(_uquad % 10);
						_uquad /= 10;
					}
					*--cp = to_char(_uquad);
					break;
 
				case HEX:
					do {
						*--cp = xdigs[_uquad & 15];
						_uquad >>= 4;
					} while (_uquad);
					break;
 
				default:
					cp = "bug in vfprintf: bad base";
					size = strlen(cp);
					goto skipsize;
				}
			}
			size = buf + BUF - cp;
		skipsize:
			break;
		default:	/* "%?" prints ?, unless ? is NUL */
			if (ch == '\0')
				goto done;
			/* pretend it was %c with argument ch */
			cp = buf;
			*cp = ch;
			size = 1;
			sign = '\0';
			break;
		}
 
		/*
		 * All reasonable formats wind up here.  At this point, `cp'
		 * points to a string which (if not flags&LADJUST) should be
		 * padded out to `width' places.  If flags&ZEROPAD, it should
		 * first be prefixed by any sign or other prefix; otherwise,
		 * it should be blank padded before the prefix is emitted.
		 * After any left-hand padding and prefixing, emit zeroes
		 * required by a decimal [diouxX] precision, then print the
		 * string proper, then emit zeroes required by any leftover
		 * floating precision; finally, if LADJUST, pad with blanks.
		 *
		 * Compute actual size, so we know how much to pad.
		 * size excludes decimal prec; realsz includes it.
		 */
		realsz = dprec > size ? dprec : size;
		if (sign)
			realsz++;
		else if (flags & HEXPREFIX)
			realsz+= 2;
 
		/* right-adjusting blank padding */
		if ((flags & (LADJUST|ZEROPAD)) == 0)
			PAD(width - realsz, blanks);
 
		/* prefix */
		if (sign) {
			PRINT(&sign, 1);
		} else if (flags & HEXPREFIX) {
			ox[0] = '0';
			ox[1] = ch;
			PRINT(ox, 2);
		}
 
		/* right-adjusting zero padding */
		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD)
			PAD(width - realsz, zeroes);
 
		/* leading zeroes from decimal precision */
		PAD(dprec - size, zeroes);
 
		/* the string or number proper */
#ifdef FLOATING_POINT
		if ((flags & FPT) == 0) {
			PRINT(cp, size);
		} else {	/* glue together f_p fragments */
			if (ch >= 'f') {	/* 'f' or 'g' */
				if (_double == 0) {
					/* kludge for __dtoa irregularity */
					PRINT("0", 1);
					if (expt < ndig || (flags & ALT) != 0) {
						PRINT(decimal_point, 1);
						PAD(ndig - 1, zeroes);
					}
				} else if (expt <= 0) {
					PRINT("0", 1);
					PRINT(decimal_point, 1);
					PAD(-expt, zeroes);
					PRINT(cp, ndig);
				} else if (expt >= ndig) {
					PRINT(cp, ndig);
					PAD(expt - ndig, zeroes);
					if (flags & ALT)
						PRINT(".", 1);
				} else {
					PRINT(cp, expt);
					cp += expt;
					PRINT(".", 1);
					PRINT(cp, ndig-expt);
				}
			} else {	/* 'e' or 'E' */
				if (ndig > 1 || flags & ALT) {
					ox[0] = *cp++;
					ox[1] = '.';
					PRINT(ox, 2);
					if (_double || flags & ALT == 0) {
						PRINT(cp, ndig-1);
					} else	/* 0.[0..] */
						/* __dtoa irregularity */
						PAD(ndig - 1, zeroes);
				} else	/* XeYYY */
					PRINT(cp, 1);
				PRINT(expstr, expsize);
			}
		}
#else
		PRINT(cp, size);
#endif
		/* left-adjusting padding (always blank) */
		if (flags & LADJUST)
			PAD(width - realsz, blanks);
 
		/* finally, adjust ret */
		ret += width > realsz ? width : realsz;
 
		FLUSH();	/* copy out the I/O vectors */
	}
done:
  va_end (ap);
	FLUSH();
	return (ret);
	/* NOTREACHED */
}
 
#ifdef FLOATING_POINT
 
extern char *_dtoa_r _PARAMS((struct _reent *, double, int,
			      int, int *, int *, char **));
 
static char *
cvt(data, value, ndigits, flags, sign, decpt, ch, length)
	struct _reent *data;
	double value;
	int ndigits, flags, *decpt, ch, *length;
	char *sign;
{
	int mode, dsgn;
	char *digits, *bp, *rve;
        union double_union tmp;
 
	if (ch == 'f') {
		mode = 3;		/* ndigits after the decimal point */
	} else {
		/* To obtain ndigits after the decimal point for the 'e' 
		 * and 'E' formats, round to ndigits + 1 significant 
		 * figures.
		 */
		if (ch == 'e' || ch == 'E') {
			ndigits++;
		}
		mode = 2;		/* ndigits significant digits */
	}
 
        tmp.d = value;
	if (word0(tmp) & Sign_bit) { /* this will check for < 0 and -0.0 */
		value = -value;
		*sign = '-';
        } else
		*sign = '\000';
	digits = _dtoa_r(data, value, mode, ndigits, decpt, &dsgn, &rve);
	if ((ch != 'g' && ch != 'G') || flags & ALT) {	/* Print trailing zeros */
		bp = digits + ndigits;
		if (ch == 'f') {
			if (*digits == '0' && value)
				*decpt = -ndigits + 1;
			bp += *decpt;
		}
		if (value == 0)	/* kludge for __dtoa irregularity */
			rve = bp;
		while (rve < bp)
			*rve++ = '0';
	}
	*length = rve - digits;
	return (digits);
}
 
static int
exponent(p0, exp, fmtch)
	char *p0;
	int exp, fmtch;
{
	register char *p, *t;
	char expbuf[MAXEXP];
 
	p = p0;
	*p++ = fmtch;
	if (exp < 0) {
		exp = -exp;
		*p++ = '-';
	}
	else
		*p++ = '+';
	t = expbuf + MAXEXP;
	if (exp > 9) {
		do {
			*--t = to_char(exp % 10);
		} while ((exp /= 10) > 9);
		*--t = to_char(exp);
		for (; t < expbuf + MAXEXP; *p++ = *t++);
	}
	else {
		*p++ = '0';
		*p++ = to_char(exp);
	}
	return (p - p0);
}
#endif /* FLOATING_POINT */