NetBSD/lib/libc/stdio/vfprintf.c

890 lines
21 KiB
C

/* $NetBSD: vfprintf.c,v 1.44 2003/01/18 11:29:59 thorpej Exp $ */
/*-
* 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.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char *sccsid = "@(#)vfprintf.c 5.50 (Berkeley) 12/16/92";
#else
__RCSID("$NetBSD: vfprintf.c,v 1.44 2003/01/18 11:29:59 thorpej Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
/*
* Actual printf innards.
*
* This code is large and complicated...
*/
#include "namespace.h"
#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include "reentrant.h"
#include "local.h"
#include "fvwrite.h"
#include "extern.h"
static int __sprint __P((FILE *, struct __suio *));
static int __sbprintf __P((FILE *, const char *, va_list))
__attribute__((__format__(__printf__, 2, 0)));
/*
* Flush out all the vectors defined by the given uio,
* then reset it so that it can be reused.
*/
static int
__sprint(fp, uio)
FILE *fp;
struct __suio *uio;
{
int err;
_DIAGASSERT(fp != NULL);
_DIAGASSERT(uio != NULL);
if (uio->uio_resid == 0) {
uio->uio_iovcnt = 0;
return (0);
}
err = __sfvwrite(fp, uio);
uio->uio_resid = 0;
uio->uio_iovcnt = 0;
return (err);
}
/*
* Helper function for `fprintf to unbuffered unix file': creates a
* temporary buffer. We only work on write-only files; this avoids
* worries about ungetc buffers and so forth.
*/
static int
__sbprintf(fp, fmt, ap)
FILE *fp;
const char *fmt;
va_list ap;
{
int ret;
FILE fake;
struct __sfileext fakeext;
unsigned char buf[BUFSIZ];
_DIAGASSERT(fp != NULL);
_DIAGASSERT(fmt != NULL);
_FILEEXT_SETUP(&fake, &fakeext);
/* copy the important variables */
fake._flags = fp->_flags & ~__SNBF;
fake._file = fp->_file;
fake._cookie = fp->_cookie;
fake._write = fp->_write;
/* set up the buffer */
fake._bf._base = fake._p = buf;
fake._bf._size = fake._w = sizeof(buf);
fake._lbfsize = 0; /* not actually used, but Just In Case */
/* do the work, then copy any error status */
ret = vfprintf(&fake, fmt, ap);
if (ret >= 0 && fflush(&fake))
ret = -1;
if (fake._flags & __SERR)
fp->_flags |= __SERR;
return (ret);
}
#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 __P((double, int, int, char *, int *, int, int *));
static int exponent __P((char *, int, int));
#else /* no FLOATING_POINT */
#define BUF 40
#endif /* FLOATING_POINT */
#ifdef lint
static __inline void *__UNCONST __P((const void *));
static __inline void *
__UNCONST(v)
const void *v;
{
/* LINTED */
return (void *) v;
}
#else
#define __UNCONST(v) (void *)(v)
#endif
/*
* 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) ((char)((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 MAXINT 0x080 /* (unsigned) intmax_t */
#define PTRINT 0x100 /* (unsigned) ptrdiff_t */
#define SIZEINT 0x200 /* (signed) size_t */
#define ZEROPAD 0x400 /* zero (as opposed to blank) pad */
#define FPT 0x800 /* Floating point number */
int
vfprintf(fp, fmt0, ap)
FILE *fp;
const char *fmt0;
_BSD_VA_LIST_ ap;
{
int ret;
FLOCKFILE(fp);
ret = vfprintf_unlocked(fp, fmt0, ap);
FUNLOCKFILE(fp);
return ret;
}
int
vfprintf_unlocked(fp, fmt0, ap)
FILE *fp;
const char *fmt0;
_BSD_VA_LIST_ ap;
{
const char *fmt;/* format string */
int ch; /* character from fmt */
int n, m; /* handy integers (short term usage) */
const char *cp; /* handy char pointer (short term usage) */
char *bp; /* handy char pointer (short term usage) */
struct __siov *iovp;/* for PRINT macro */
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) */
wchar_t wc;
mbstate_t ps;
#ifdef FLOATING_POINT
char *decimal_point = localeconv()->decimal_point;
char softsign; /* temporary negative sign for floats */
double _double = 0; /* double precision arguments %[eEfgG] */
int expt; /* integer value of exponent */
int expsize = 0; /* character count for expstr */
int ndig; /* actual number of digits returned by cvt */
char expstr[7]; /* buffer for exponent string */
#endif
#ifdef __GNUC__ /* gcc has builtin quad type (long long) SOS */
#define quad_t long long
#define u_quad_t unsigned long long
#endif
#define INTMAX_T intmax_t
#define UINTMAX_T uintmax_t
UINTMAX_T _uintmax; /* integer arguments %[diouxX] */
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 = NULL; /* digits for [xX] conversion */
#define NIOV 8
struct __suio uio; /* output information: summary */
struct __siov iov[NIOV];/* ... and individual io vectors */
char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */
char ox[2]; /* space for 0x hex-prefix */
/*
* 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'};
/*
* BEWARE, these `goto error' on error, and PAD uses `n'.
*/
#define PRINT(ptr, len) { \
iovp->iov_base = __UNCONST(ptr); \
iovp->iov_len = (len); \
uio.uio_resid += (len); \
iovp++; \
if (++uio.uio_iovcnt >= NIOV) { \
if (__sprint(fp, &uio)) \
goto error; \
iovp = iov; \
} \
}
#define PAD(howmany, with) { \
if ((n = (howmany)) > 0) { \
while (n > PADSIZE) { \
PRINT(with, PADSIZE); \
n -= PADSIZE; \
} \
PRINT(with, n); \
} \
}
#define FLUSH() { \
if (uio.uio_resid && __sprint(fp, &uio)) \
goto error; \
uio.uio_iovcnt = 0; \
iovp = iov; \
}
/*
* To extend shorts properly, we need both signed and unsigned
* argument extraction methods.
*/
#define SARG() \
(flags&MAXINT ? va_arg(ap, intmax_t) : \
flags&PTRINT ? va_arg(ap, ptrdiff_t) : \
flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \
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&MAXINT ? va_arg(ap, uintmax_t) : \
flags&PTRINT ? va_arg(ap, uintptr_t) : /* XXX */ \
flags&SIZEINT ? va_arg(ap, size_t) : \
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))
_DIAGASSERT(fp != NULL);
_DIAGASSERT(fmt0 != NULL);
_SET_ORIENTATION(fp, -1);
/* sorry, fprintf(read_only_file, "") returns -1, not 0 */
if (cantwrite(fp)) {
errno = EBADF;
return (-1);
}
/* optimise fprintf(stderr) (and other unbuffered Unix files) */
if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
fp->_file >= 0) {
ret = __sbprintf(fp, fmt0, ap);
return (ret);
}
fmt = fmt0;
uio.uio_iov = iovp = iov;
uio.uio_resid = 0;
uio.uio_iovcnt = 0;
ret = 0;
memset(&ps, 0, sizeof(ps));
/*
* Scan the format for conversions (`%' character).
*/
for (;;) {
cp = fmt;
while ((n = mbrtowc(&wc, fmt, MB_CUR_MAX, &ps)) > 0) {
fmt += n;
if (wc == '%') {
fmt--;
break;
}
}
if ((m = fmt - cp) != 0) {
PRINT(cp, m);
ret += m;
}
if (n <= 0)
goto done;
fmt++; /* skip over '%' */
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 'j':
flags |= MAXINT;
goto rflag;
case 'l':
if (*fmt == 'l') {
fmt++;
flags |= QUADINT;
} else {
flags |= LONGINT;
}
goto rflag;
case 'q':
flags |= QUADINT;
goto rflag;
case 't':
flags |= PTRINT;
goto rflag;
case 'z':
flags |= SIZEINT;
goto rflag;
case 'c':
*buf = va_arg(ap, int);
cp = buf;
size = 1;
sign = '\0';
break;
case 'D':
flags |= LONGINT;
/*FALLTHROUGH*/
case 'd':
case 'i':
_uintmax = SARG();
if ((intmax_t)_uintmax < 0) {
_uintmax = -_uintmax;
sign = '-';
}
base = DEC;
goto number;
#ifdef FLOATING_POINT
case 'e':
case 'E':
case 'f':
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 = '-';
if (ch == 'E' || ch == 'F' || ch == 'G')
cp = "INF";
else
cp = "inf";
size = 3;
break;
}
if (isnan(_double)) {
if (ch == 'E' || ch == 'F' || ch == 'G')
cp = "NAN";
else
cp = "nan";
size = 3;
break;
}
flags |= FPT;
cp = cvt(_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' || ch == 'E') {
--expt;
expsize = exponent(expstr, expt, ch);
size = expsize + ndig;
if (ndig > 1 || flags & ALT)
++size;
} else if (ch == 'f' || ch == 'F') {
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':
if (flags & MAXINT)
*va_arg(ap, intmax_t *) = ret;
else if (flags & PTRINT)
*va_arg(ap, ptrdiff_t *) = ret;
else if (flags & SIZEINT)
*va_arg(ap, ssize_t *) = ret; /* XXX */
else if (flags & QUADINT)
*va_arg(ap, quad_t *) = ret;
else 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':
_uintmax = 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 */
_uintmax = (u_long)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 = memchr(cp, 0, (size_t)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':
_uintmax = UARG();
base = DEC;
goto nosign;
case 'X':
xdigs = "0123456789ABCDEF";
goto hex;
case 'x':
xdigs = "0123456789abcdef";
hex: _uintmax = UARG();
base = HEX;
/* leading 0x/X only if non-zero */
if (flags & ALT && _uintmax != 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
*/
bp = buf + BUF;
if (_uintmax != 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 {
*--bp = to_char(_uintmax & 7);
_uintmax >>= 3;
} while (_uintmax);
/* handle octal leading 0 */
if (flags & ALT && *bp != '0')
*--bp = '0';
break;
case DEC:
/* many numbers are 1 digit */
while (_uintmax >= 10) {
*--bp = to_char(_uintmax % 10);
_uintmax /= 10;
}
*--bp = to_char(_uintmax);
break;
case HEX:
do {
*--bp = xdigs[(size_t)
(_uintmax & 15)];
_uintmax >>= 4;
} while (_uintmax);
break;
default:
cp = "bug in vfprintf: bad base";
size = strlen(cp);
goto skipsize;
}
}
cp = bp;
size = buf + BUF - bp;
skipsize:
break;
default: /* "%?" prints ?, unless ? is NUL */
if (ch == '\0')
goto done;
/* pretend it was %c with argument ch */
*buf = ch;
cp = buf;
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) {
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:
FLUSH();
error:
if (__sferror(fp))
ret = -1;
return (ret);
}
#ifdef FLOATING_POINT
static char *
cvt(value, ndigits, flags, sign, decpt, ch, length)
double value;
int ndigits, flags, *decpt, ch, *length;
char *sign;
{
int mode, dsgn;
char *digits, *bp, *rve;
_DIAGASSERT(decpt != NULL);
_DIAGASSERT(length != NULL);
_DIAGASSERT(sign != NULL);
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 */
}
digits = __dtoa(value, mode, ndigits, decpt, &dsgn, &rve);
if (dsgn) {
value = -value;
*sign = '-';
} else
*sign = '\000';
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, expon, fmtch)
char *p0;
int expon, fmtch;
{
char *p, *t;
char expbuf[MAXEXP];
_DIAGASSERT(p0 != NULL);
p = p0;
*p++ = fmtch;
if (expon < 0) {
expon = -expon;
*p++ = '-';
}
else
*p++ = '+';
t = expbuf + MAXEXP;
if (expon > 9) {
do {
*--t = to_char(expon % 10);
} while ((expon /= 10) > 9);
*--t = to_char(expon);
for (; t < expbuf + MAXEXP; *p++ = *t++);
}
else {
*p++ = '0';
*p++ = to_char(expon);
}
return (p - p0);
}
#endif /* FLOATING_POINT */