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checkpoint; gonna try and rewrite floating point
[unix-history] / usr / src / lib / libc / stdio / vfprintf.c
/*
* Copyright (c) 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that this notice is preserved and that due credit is given
* to the University of California at Berkeley. The name of the University
* may not be used to endorse or promote products derived from this
* software without specific prior written permission. This software
* is provided ``as is'' without express or implied warranty.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)vfprintf.c 5.7 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <varargs.h>
#include <stdio.h>
#include <ctype.h>
#define MAXBUF 120
#define DEFPREC 6
#define PUTC(ch, fd) {++cnt; putc(ch, fd);}
#define EFORMAT 1
#define FFORMAT 2
#define GFORMAT 3
#define LONGINT 0x01
#define LONGDBL 0x02
#define SHORTINT 0x04
#define GETARG(r) \
r = argsize&LONGINT ? va_arg(argp, long) : \
argsize&SHORTINT ? va_arg(argp, short) : va_arg(argp, int);
x_doprnt(fmt, argp, fp)
register char *fmt;
va_list argp;
register FILE *fp;
{
register u_long reg_ulong;
register long reg_long;
register int base;
register char *digs, *bp, *t, padc;
double _double;
char argsize, printsign, *_cvt(), buf[MAXBUF];
int alternate, cnt, n, ladjust, width, prec, size;
digs = "0123456789abcdef";
for (cnt = 0; *fmt; ++fmt) {
if (*fmt != '%') {
PUTC(*fmt, fp);
continue;
}
alternate = ladjust = width = 0;
prec = -1;
padc = ' ';
argsize = printsign = '\0';
flags: switch (*++fmt) {
case '#':
alternate = 1;
goto flags;
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(argp, int)) >= 0)
goto flags;
width = -width;
/*FALLTHROUGH*/
case '-':
ladjust = 1;
goto flags;
case '+':
printsign = '+';
goto flags;
case '.':
if (*++fmt == '*')
prec = va_arg(argp, int);
else if (isdigit(*fmt)) {
prec = 0;
do {
prec = 10 * prec + *fmt - '0';
} while isdigit(*++fmt);
--fmt;
}
else {
prec = 0;
--fmt;
goto flags;
}
if (prec < 0)
prec = -1;
goto flags;
case '0':
padc = '0';
/*FALLTHROUGH*/
case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
do {
width = 10 * width + *fmt - '0';
} while isdigit(*++fmt);
--fmt;
case 'L':
argsize |= LONGDBL;
goto flags;
case 'h':
argsize |= SHORTINT;
goto flags;
case 'l':
argsize |= LONGINT;
goto flags;
case '%': /* "%#%" prints as "%" */
PUTC('%', fp);
break;
case 'c': {
char ch;
ch = va_arg(argp, int);
PUTC(ch, fp);
break;
}
case 'd':
case 'i':
GETARG(reg_long);
if (reg_long < 0) {
reg_ulong = -reg_long;
printsign = '-';
}
else {
reg_ulong = reg_long;
}
if (printsign)
PUTC(printsign, fp);
base = 10;
goto num1;
case 'E':
case 'e':
_double = va_arg(argp, double);
bp = _cvt(_double, prec, buf, EFORMAT, *fmt,
printsign, alternate);
goto pbuf;
case 'f':
_double = va_arg(argp, double);
bp = _cvt(_double, prec, buf, FFORMAT, 'f',
printsign, alternate);
goto pbuf;
case 'G':
case 'g':
_double = va_arg(argp, double);
bp = _cvt(_double, prec, buf, GFORMAT, *fmt - 2,
printsign, alternate);
pbuf: size = bp - buf;
if (size < width && !ladjust)
do {
PUTC(padc, fp);
} while (--width > size);
for (t = buf; t < bp; ++t)
PUTC(*t, fp);
for (; width > size; --width)
PUTC(padc, fp);
break;
case 'n':
*(va_arg(argp, int *)) = cnt;
break;
case 'o':
GETARG(reg_ulong);
base = 8;
if (!reg_ulong || !alternate)
goto num1;
bp = buf + sizeof(buf) - 1;
do {
*bp-- = digs[reg_ulong % base];
reg_ulong /= base;
} while(reg_ulong);
size = &buf[sizeof(buf) - 1] - bp;
if (size < --width && !ladjust)
do {
PUTC(padc, fp);
} while (--width > size);
PUTC('0', fp);
goto num2;
case 'p':
case 's':
if (!(bp = va_arg(argp, char *)))
bp = "(null)";
if (width > 0 && !ladjust) {
char *savep;
savep = bp;
for (n = 0; *bp && (prec < 0 || n < prec);
n++, bp++);
bp = savep;
while (n++ < width)
PUTC(' ', fp);
}
for (n = 0; *bp; ++bp) {
if (++n > prec && prec >= 0)
break;
PUTC(*bp, fp);
}
if (n < width && ladjust)
do {
PUTC(' ', fp);
} while (++n < width);
break;
case 'u':
GETARG(reg_ulong);
base = 10;
goto num1;
case 'X':
digs = "0123456789ABCDEF";
/*FALLTHROUGH*/
case 'x':
GETARG(reg_ulong);
if (alternate && reg_ulong) {
PUTC('0', fp);
PUTC(*fmt, fp);
}
base = 16;
num1: bp = buf + sizeof(buf) - 1;
do {
*bp-- = digs[reg_ulong % base];
reg_ulong /= base;
} while(reg_ulong);
size = &buf[sizeof(buf) - 1] - bp;
for (; size < prec; *bp-- = '0', ++size);
if (size < width && !ladjust)
do {
PUTC(padc, fp);
} while (--width > size);
num2: while (++bp != &buf[MAXBUF])
PUTC(*bp, fp);
for (; width > size; --width)
PUTC(padc, fp);
digs = "0123456789abcdef";
break;
case '\0': /* "%?" prints ?, unless ? is NULL */
return(ferror(fp) ? -1 : cnt);
default:
PUTC(*fmt, fp);
}
}
return(ferror(fp) ? -1 : cnt);
}
char *
_cvt(number, prec, bp, format, fmtch, printsign, alternate)
double number;
int prec, format, alternate;
register char *bp;
char fmtch, printsign;
{
int sign, decpt;
register char *t;
register int n;
double fabs();
char *ecvt(), *fcvt();
if (prec == -1)
prec = DEFPREC;
t = fabs(number) < 1 ? ecvt(number, prec + 1, &decpt, &sign) :
fcvt(number, prec + 1, &decpt, &sign);
if (sign)
*bp++ = '-';
else if (printsign)
*bp++ = printsign;
/* E format */
/* use 'e' format if exponent > precision or less than -4 */
if (format == EFORMAT ||
format == GFORMAT && (decpt > prec || decpt < -3)) {
*bp++ = *t ? *t++ : '0';
if (format != GFORMAT && prec || prec > 1) {
*bp++ = '.';
while(prec--)
*bp++ = *t ? *t++ : '0';
}
else if (alternate)
*bp++ = '.';
if (*t && *t > '4')
++bp[-1];
if (format == GFORMAT && !alternate) {
for (; bp[-1] == '0'; --bp);
if (bp[-1] == '.')
--bp;
}
*bp++ = fmtch;
if (--decpt < 0) {
decpt = -decpt;
*bp++ = '-';
}
else
*bp++ = '+';
*bp++ = decpt / 10 + '0';
*bp++ = decpt % 10 + '0';
}
/* F format */
else {
if (decpt <= 0) {
*bp++ = '0';
if (prec) {
*bp++ = '.';
if (format == FFORMAT)
while (decpt++ < 0 && prec--)
*bp++ = '0';
else while (decpt++ < 0)
*bp++ = '0';
}
else if (alternate)
*bp++ = '.';
}
else {
for (n = 1; n <= decpt; n++)
*bp++ = *t++;
if (prec || alternate)
*bp++ = '.';
}
for (n = 1; n <= prec; n++)
*bp++ = *t ? *t++ : '0';
if (format == GFORMAT && !alternate) {
for (; bp[-1] == '0'; --bp);
if (bp[-1] == '.')
--bp;
}
}
return(bp);
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.