File: [local] / prex / usr / lib / libc / stdio / vfprintf.c (download)
Revision 1.1.1.1 (vendor branch), Tue Aug 19 12:46:58 2008 UTC (16 years ago) by nbrk
Branch: MAIN, KOHSUKE
CVS Tags: PREX_0_8_BASE, HEAD Changes since 1.1: +0 -0 lines
Initial import of Prex, Portable Real-time Embedded POSIX microkernel system.
I have totally new directions in my development (more focused on real hardware, not virtual one).
Old hacks are available in prex-old module. They will be carefully re-designed and merged soon.
|
/*-
* Copyright (c) 1990, 1993
* 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. 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.
*/
/*
* Actual printf innards.
*
* This code is large and complicated...
*/
#include <sys/types.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include "local.h"
#include "fvwrite.h"
/*
* Flush out all the vectors defined by the given uio,
* then reset it so that it can be reused.
*/
static int
__sprint(FILE *fp, struct __suio *uio)
{
int err;
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(FILE *fp, const char *fmt, va_list ap)
{
int ret;
FILE fake;
unsigned char buf[BUFSIZ];
/* copy the important variables */
fake._flags = fp->_flags & ~__SNBF;
fake._file = fp->_file;
/* set up the buffer */
fake._bf._base = fake._p = buf;
fake._bf._size = fake._w = sizeof(buf);
/* do the work, then copy any error status */
ret = vfprintf(&fake, fmt, ap);
if (ret >= 0 && fflush(&fake))
ret = EOF;
if (fake._flags & __SERR)
fp->_flags |= __SERR;
return (ret);
}
/*
* 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')
/*
* Convert an unsigned long to ASCII for printf purposes, returning
* a pointer to the first character of the string representation.
* Octal numbers can be forced to have a leading zero; hex numbers
* use the given digits.
*/
static char *
__ultoa(u_long val, char *endp, int base, int octzero, char *xdigs)
{
char *cp = endp;
long sval;
/*
* Handle the three cases separately, in the hope of getting
* better/faster code.
*/
switch (base) {
case 10:
if (val < 10) { /* many numbers are 1 digit */
*--cp = to_char(val);
return (cp);
}
/*
* On many machines, unsigned arithmetic is harder than
* signed arithmetic, so we do at most one unsigned mod and
* divide; this is sufficient to reduce the range of
* the incoming value to where signed arithmetic works.
*/
if (val > LONG_MAX) {
*--cp = to_char(val % 10);
sval = val / 10;
} else
sval = val;
do {
*--cp = to_char(sval % 10);
sval /= 10;
} while (sval != 0);
break;
case 8:
do {
*--cp = to_char(val & 7);
val >>= 3;
} while (val);
if (octzero && *cp != '0')
*--cp = '0';
break;
case 16:
do {
*--cp = xdigs[val & 15];
val >>= 4;
} while (val);
break;
default: /* oops */
abort();
}
return (cp);
}
#define BUF 32
/*
* 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 SHORTINT 0x040 /* short integer */
#define ZEROPAD 0x080 /* zero (as opposed to blank) pad */
int
vfprintf(fp, fmt0, ap)
FILE *fp;
const char *fmt0;
va_list ap;
{
char *fmt; /* format string */
int ch; /* character from fmt */
int n; /* handy integer (short term usage) */
char *cp; /* 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) */
u_long ulval; /* integer arguments %[diouxX] */
int base; /* base for [diouxX] conversion */
int dprec; /* a copy of prec if [diouxX], 0 otherwise */
int fieldsz; /* field size expanded by sign, etc */
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 char blanks[PADSIZE] =
{' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
static 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 = (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&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))
/* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
if (cantwrite(fp))
return (EOF);
/* optimise fprintf(stderr) (and other unbuffered Unix files) */
if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&
fp->_file >= 0)
return (__sbprintf(fp, fmt0, ap));
fmt = (char *)fmt0;
uio.uio_iov = iovp = iov;
uio.uio_resid = 0;
uio.uio_iovcnt = 0;
ret = 0;
/*
* Scan the format for conversions (`%' character).
*/
for (;;) {
for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
/* void */;
if ((n = fmt - cp) != 0) {
PRINT(cp, n);
ret += n;
}
if (ch == '\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;
case 'h':
flags |= SHORTINT;
goto rflag;
case 'l':
flags |= LONGINT;
goto rflag;
case 'c':
*(cp = buf) = va_arg(ap, int);
size = 1;
sign = '\0';
break;
case 'D':
flags |= LONGINT;
/*FALLTHROUGH*/
case 'd':
case 'i':
ulval = SARG();
if ((long)ulval < 0) {
ulval = -ulval;
sign = '-';
}
base = 10;
goto number;
case 'n':
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':
ulval = UARG();
base = 8;
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
*/
ulval = (u_long)va_arg(ap, void *);
base = 16;
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, 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':
ulval = UARG();
base = 10;
goto nosign;
case 'X':
xdigs = "0123456789ABCDEF";
goto hex;
case 'x':
xdigs = "0123456789abcdef";
hex:
ulval = UARG();
base = 16;
/* leading 0x/X only if non-zero */
if (flags & ALT && ulval != 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 (ulval != 0 || prec != 0)
cp = __ultoa(ulval, cp, base,
flags & ALT, xdigs);
size = buf + BUF - cp;
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.
* fieldsz excludes decimal prec; realsz includes it.
*/
fieldsz = size;
if (sign)
fieldsz++;
else if (flags & HEXPREFIX)
fieldsz += 2;
realsz = dprec > fieldsz ? dprec : fieldsz;
/* 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 - fieldsz, zeroes);
/* the string or number proper */
PRINT(cp, size);
/* 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:
return (__sferror(fp) ? EOF : ret);
/* NOTREACHED */
}