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bradley219/vfprintf.c

Created June 1, 2013 23:58
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Modified version of vfprintf.c from the avr-libc library. Adds the format specifier `%b' to the printf family of functions to allow printing an integer in binary (base 2) representation.
Raw
vfprintf.c
/* Copyright (c) 2002, Alexander Popov ([email protected])
Copyright (c) 2002,2004,2005 Joerg Wunsch
Copyright (c) 2005, Helmut Wallner
Copyright (c) 2007, Dmitry Xmelkov
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* 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.
* Neither the name of the copyright holders nor the names of
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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 BINARY_SUPPORT
/* From: Id: printf_p_new.c,v 1.1.1.9 2002/10/15 20:10:28 joerg_wunsch Exp */
/* $Id: vfprintf.c 2191 2010-11-05 13:45:57Z arcanum $ */
#if !defined(__AVR_TINY__)
#include <avr/pgmspace.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "sectionname.h"
#include "stdio_private.h"
#include "ftoa_engine.h"
#include "ntz.h"
#include "xtoa_fast.h"
/*
* This file can be compiled into more than one flavour. The default
* is to offer the usual modifiers and integer formatting support
* (level 2). Level 1 maintains a minimal version that just offers
* integer formatting, but no modifier support whatsoever. Level 3 is
* intented for floating point support.
*/
#ifdef BINARY_SUPPORT
/* (c)2011 Bradley Snyder -- binary printing support via %b */
char *__bin_invert( unsigned long val, char *str ) {
if( val == 0 ) {
*str = '0';
str++;
}
else {
while( val ) {
*str++ = (val & 0x01 ) ? '1' : '0' ;
val >>= 1;
}
}
return str;
}
#endif
#ifndef PRINTF_LEVEL
# define PRINTF_LEVEL PRINTF_STD
#endif
#if PRINTF_LEVEL == PRINTF_MIN || PRINTF_LEVEL == PRINTF_STD \
|| PRINTF_LEVEL == PRINTF_FLT
/* OK */
#else
# error "Not a known printf level."
#endif
#ifndef __AVR_HAVE_LPMX__
# if defined(__AVR_ENHANCED__) && __AVR_ENHANCED__
# define __AVR_HAVE_LPMX__ 1
# endif
#endif
#if defined(__AVR_HAVE_LPMX__) && __AVR_HAVE_LPMX__
# define GETBYTE(flag, mask, pnt) ({ \
unsigned char __c; \
asm ( \
"sbrc %2,%3 \n\t" \
"lpm %0,Z+ \n\t" \
"sbrs %2,%3 \n\t" \
"ld %0,Z+ " \
: "=r" (__c), \
"+z" (pnt) \
: "r" (flag), \
"I" (ntz(mask)) \
); \
__c; \
})
#elif 1
# define GETBYTE(flag, mask, pnt) ({ \
unsigned char __c; \
asm ( \
"sbrc %2,%3 \n\t" \
"lpm \n\t" \
"sbrs %2,%3 \n\t" \
"ld r0,Z \n\t" \
"adiw r30,1 \n\t" \
"mov %0,r0 " \
: "=r" (__c), \
"+z" (pnt) \
: "r" (flag), \
"I" (ntz(mask)) \
: "r0" \
); \
__c; \
})
#else
# define GETBYTE(flag, mask, pnt) ({ \
unsigned char __c; \
__c = ((flag) & (mask)) \
? pgm_read_byte(pnt) : *pnt; \
pnt++; \
__c; \
})
#endif
/* -------------------------------------------------------------------- */
#if PRINTF_LEVEL <= PRINTF_MIN
#define FL_PGMSTRING 0x01
#define FL_ALTHEX 0x04
#define FL_ALT 0x10
#define FL_ALTLWR 0x20
#define FL_NEGATIVE 0x40
#define FL_LONG 0x80
ATTRIBUTE_CLIB_SECTION
int
vfprintf (FILE * stream, const char *fmt, va_list ap)
{
unsigned char c; /* holds a char from the format string */
unsigned char flags;
unsigned char buf[11]; /* size for -1 in octal, without '\0' */
stream->len = 0;
if ((stream->flags & __SWR) == 0)
return EOF;
for (;;) {
for (;;) {
c = GETBYTE (stream->flags, __SPGM, fmt);
if (!c) goto ret;
if (c == '%') {
c = GETBYTE (stream->flags, __SPGM, fmt);
if (c != '%') break;
}
putc (c, stream);
}
for (flags = 0;
!(flags & FL_LONG); /* 'll' will detect as error */
c = GETBYTE (stream->flags, __SPGM, fmt))
{
if (c && strchr_P (PSTR(" +-.0123456789h"), c))
continue;
if (c == '#') {
flags |= FL_ALT;
continue;
}
if (c == 'l') {
flags |= FL_LONG;
continue;
}
break;
}
/* Only a format character is valid. */
if (c && strchr_P (PSTR("EFGefg"), c)) {
(void) va_arg (ap, double);
putc ('?', stream);
continue;
}
{
const char * pnt;
switch (c) {
case 'c':
putc (va_arg (ap, int), stream);
continue;
case 'S':
flags |= FL_PGMSTRING;
/* FALLTHROUGH */
case 's':
pnt = va_arg (ap, char *);
while ( (c = GETBYTE (flags, FL_PGMSTRING, pnt)) != 0)
putc (c, stream);
continue;
}
}
if (c == 'd' || c == 'i') {
long x = (flags & FL_LONG) ? va_arg(ap,long) : va_arg(ap,int);
flags &= ~FL_ALT;
if (x < 0) {
x = -x;
/* `putc ('-', stream)' will considarably inlarge stack size.
So flag is used. */
flags |= FL_NEGATIVE;
}
c = __ultoa_invert (x, (char *)buf, 10) - (char *)buf;
} else {
int base;
switch (c) {
case 'u':
flags &= ~FL_ALT;
base = 10;
goto ultoa;
case 'o':
base = 8;
goto ultoa;
case 'p':
flags |= FL_ALT;
/* no break */
case 'x':
flags |= (FL_ALTHEX | FL_ALTLWR);
base = 16;
goto ultoa;
case 'X':
flags |= FL_ALTHEX;
base = 16 | XTOA_UPPER;
ultoa:
c = __ultoa_invert ((flags & FL_LONG)
? va_arg(ap, unsigned long)
: va_arg(ap, unsigned int),
(char *)buf, base) - (char *)buf;
break;
#ifdef BINARY_SUPPORT
case 'b':
c = __bin_invert ((flags & FL_LONG)
? va_arg(ap, unsigned long)
: va_arg(ap, unsigned int),
(char *)buf ) - (char *)buf;
break;
#endif
default:
goto ret;
}
}
/* Integer number output. */
if (flags & FL_NEGATIVE)
putc ('-', stream);
if ((flags & FL_ALT) && (buf[c-1] != '0')) {
putc ('0', stream);
if (flags & FL_ALTHEX)
#if FL_ALTLWR != 'x' - 'X'
# error
#endif
putc ('X' + (flags & FL_ALTLWR), stream);
}
do {
putc (buf[--c], stream);
} while (c);
} /* for (;;) */
ret:
return stream->len;
}
/* -------------------------------------------------------------------- */
#else /* i.e. PRINTF_LEVEL > PRINTF_MIN */
#define FL_ZFILL 0x01
#define FL_PLUS 0x02
#define FL_SPACE 0x04
#define FL_LPAD 0x08
#define FL_ALT 0x10
#define FL_WIDTH 0x20
#define FL_PREC 0x40
#define FL_LONG 0x80
#define FL_PGMSTRING FL_LONG
#define FL_NEGATIVE FL_LONG
#define FL_ALTUPP FL_PLUS
#define FL_ALTHEX FL_SPACE
#define FL_FLTUPP FL_ALT
#define FL_FLTEXP FL_PREC
#define FL_FLTFIX FL_LONG
ATTRIBUTE_CLIB_SECTION
int vfprintf (FILE * stream, const char *fmt, va_list ap)
{
unsigned char c; /* holds a char from the format string */
unsigned char flags;
unsigned char width;
unsigned char prec;
unsigned char buf[11]; /* size for -1 in octal, without '\0' */
stream->len = 0;
if ((stream->flags & __SWR) == 0)
return EOF;
for (;;) {
for (;;) {
c = GETBYTE (stream->flags, __SPGM, fmt);
if (!c) goto ret;
if (c == '%') {
c = GETBYTE (stream->flags, __SPGM, fmt);
if (c != '%') break;
}
putc (c, stream);
}
flags = 0;
width = 0;
prec = 0;
do {
if (flags < FL_WIDTH) {
switch (c) {
case '0':
flags |= FL_ZFILL;
continue;
case '+':
flags |= FL_PLUS;
/* FALLTHROUGH */
case ' ':
flags |= FL_SPACE;
continue;
case '-':
flags |= FL_LPAD;
continue;
case '#':
flags |= FL_ALT;
continue;
}
}
if (flags < FL_LONG) {
if (c >= '0' && c <= '9') {
c -= '0';
if (flags & FL_PREC) {
prec = 10*prec + c;
continue;
}
width = 10*width + c;
flags |= FL_WIDTH;
continue;
}
if (c == '.') {
if (flags & FL_PREC)
goto ret;
flags |= FL_PREC;
continue;
}
if (c == 'l') {
flags |= FL_LONG;
continue;
}
if (c == 'h')
continue;
}
break;
} while ( (c = GETBYTE (stream->flags, __SPGM, fmt)) != 0);
/* Only a format character is valid. */
#if 'F' != 'E'+1 || 'G' != 'F'+1 || 'f' != 'e'+1 || 'g' != 'f'+1
# error
#endif
#if PRINTF_LEVEL >= PRINTF_FLT
if (c >= 'E' && c <= 'G') {
flags |= FL_FLTUPP;
c += 'e' - 'E';
goto flt_oper;
} else if (c >= 'e' && c <= 'g') {
int exp; /* exponent of master decimal digit */
int n;
unsigned char vtype; /* result of float value parse */
unsigned char sign; /* sign character (or 0) */
# define ndigs c /* only for this block, undef is below */
flags &= ~FL_FLTUPP;
flt_oper:
if (!(flags & FL_PREC))
prec = 6;
flags &= ~(FL_FLTEXP | FL_FLTFIX);
if (c == 'e')
flags |= FL_FLTEXP;
else if (c == 'f')
flags |= FL_FLTFIX;
else if (prec > 0)
prec -= 1;
if (flags & FL_FLTFIX) {
vtype = 7; /* 'prec' arg for 'ftoa_engine' */
ndigs = prec < 60 ? prec + 1 : 60;
} else {
if (prec > 7) prec = 7;
vtype = prec;
ndigs = 0;
}
exp = __ftoa_engine (va_arg(ap,double), (char *)buf, vtype, ndigs);
vtype = buf[0];
sign = 0;
if ((vtype & FTOA_MINUS) && !(vtype & FTOA_NAN))
sign = '-';
else if (flags & FL_PLUS)
sign = '+';
else if (flags & FL_SPACE)
sign = ' ';
if (vtype & (FTOA_NAN | FTOA_INF)) {
const char *p;
ndigs = sign ? 4 : 3;
if (width > ndigs) {
width -= ndigs;
if (!(flags & FL_LPAD)) {
do {
putc (' ', stream);
} while (--width);
}
} else {
width = 0;
}
if (sign)
putc (sign, stream);
p = PSTR("inf");
if (vtype & FTOA_NAN)
p = PSTR("nan");
# if ('I'-'i' != 'N'-'n') || ('I'-'i' != 'F'-'f') || ('I'-'i' != 'A'-'a')
# error
# endif
while ( (ndigs = pgm_read_byte(p)) != 0) {
if (flags & FL_FLTUPP)
ndigs += 'I' - 'i';
putc (ndigs, stream);
p++;
}
goto tail;
}
/* Output format adjustment, number of decimal digits in buf[] */
if (flags & FL_FLTFIX) {
ndigs += exp;
if ((vtype & FTOA_CARRY) && buf[1] == '1')
ndigs -= 1;
if ((signed char)ndigs < 1)
ndigs = 1;
else if (ndigs > 8)
ndigs = 8;
} else if (!(flags & FL_FLTEXP)) { /* 'g(G)' format */
if (exp <= prec && exp >= -4)
flags |= FL_FLTFIX;
while (prec && buf[1+prec] == '0')
prec--;
if (flags & FL_FLTFIX) {
ndigs = prec + 1; /* number of digits in buf */
prec = prec > exp
? prec - exp : 0; /* fractional part length */
}
}
/* Conversion result length, width := free space length */
if (flags & FL_FLTFIX)
n = (exp>0 ? exp+1 : 1);
else
n = 5; /* 1e+00 */
if (sign) n += 1;
if (prec) n += prec + 1;
width = width > n ? width - n : 0;
/* Output before first digit */
if (!(flags & (FL_LPAD | FL_ZFILL))) {
while (width) {
putc (' ', stream);
width--;
}
}
if (sign) putc (sign, stream);
if (!(flags & FL_LPAD)) {
while (width) {
putc ('0', stream);
width--;
}
}
if (flags & FL_FLTFIX) { /* 'f' format */
n = exp > 0 ? exp : 0; /* exponent of left digit */
do {
if (n == -1)
putc ('.', stream);
flags = (n <= exp && n > exp - ndigs)
? buf[exp - n + 1] : '0';
if (--n < -prec)
break;
putc (flags, stream);
} while (1);
if (n == exp
&& (buf[1] > '5'
|| (buf[1] == '5' && !(vtype & FTOA_CARRY))) )
{
flags = '1';
}
putc (flags, stream);
} else { /* 'e(E)' format */
/* mantissa */
if (buf[1] != '1')
vtype &= ~FTOA_CARRY;
putc (buf[1], stream);
if (prec) {
putc ('.', stream);
sign = 2;
do {
putc (buf[sign++], stream);
} while (--prec);
}
/* exponent */
putc (flags & FL_FLTUPP ? 'E' : 'e', stream);
ndigs = '+';
if (exp < 0 || (exp == 0 && (vtype & FTOA_CARRY) != 0)) {
exp = -exp;
ndigs = '-';
}
putc (ndigs, stream);
for (ndigs = '0'; exp >= 10; exp -= 10)
ndigs += 1;
putc (ndigs, stream);
putc ('0' + exp, stream);
}
goto tail;
# undef ndigs
}
#else /* to: PRINTF_LEVEL >= PRINTF_FLT */
if ((c >= 'E' && c <= 'G') || (c >= 'e' && c <= 'g')) {
(void) va_arg (ap, double);
buf[0] = '?';
goto buf_addr;
}
#endif
{
const char * pnt;
size_t size;
switch (c) {
case 'c':
buf[0] = va_arg (ap, int);
#if PRINTF_LEVEL < PRINTF_FLT
buf_addr:
#endif
pnt = (char *)buf;
size = 1;
goto no_pgmstring;
case 's':
pnt = va_arg (ap, char *);
size = strnlen (pnt, (flags & FL_PREC) ? prec : ~0);
no_pgmstring:
flags &= ~FL_PGMSTRING;
goto str_lpad;
case 'S':
pnt = va_arg (ap, char *);
size = strnlen_P (pnt, (flags & FL_PREC) ? prec : ~0);
flags |= FL_PGMSTRING;
str_lpad:
if (!(flags & FL_LPAD)) {
while (size < width) {
putc (' ', stream);
width--;
}
}
while (size) {
putc (GETBYTE (flags, FL_PGMSTRING, pnt), stream);
if (width) width -= 1;
size -= 1;
}
goto tail;
}
}
if (c == 'd' || c == 'i') {
long x = (flags & FL_LONG) ? va_arg(ap,long) : va_arg(ap,int);
flags &= ~(FL_NEGATIVE | FL_ALT);
if (x < 0) {
x = -x;
flags |= FL_NEGATIVE;
}
c = __ultoa_invert (x, (char *)buf, 10) - (char *)buf;
} else {
int base;
if (c == 'u') {
flags &= ~FL_ALT;
base = 10;
goto ultoa;
}
flags &= ~(FL_PLUS | FL_SPACE);
switch (c) {
case 'o':
base = 8;
goto ultoa;
case 'p':
flags |= FL_ALT;
/* no break */
case 'x':
if (flags & FL_ALT)
flags |= FL_ALTHEX;
base = 16;
goto ultoa;
case 'X':
if (flags & FL_ALT)
flags |= (FL_ALTHEX | FL_ALTUPP);
base = 16 | XTOA_UPPER;
ultoa:
c = __ultoa_invert ((flags & FL_LONG)
? va_arg(ap, unsigned long)
: va_arg(ap, unsigned int),
(char *)buf, base) - (char *)buf;
flags &= ~FL_NEGATIVE;
break;
#ifdef BINARY_SUPPORT
case 'b':
c = __bin_invert ((flags & FL_LONG)
? va_arg(ap, unsigned long)
: va_arg(ap, unsigned int),
(char *)buf ) - (char *)buf;
break;
#endif
default:
goto ret;
}
}
{
unsigned char len;
len = c;
if (flags & FL_PREC) {
flags &= ~FL_ZFILL;
if (len < prec) {
len = prec;
if ((flags & FL_ALT) && !(flags & FL_ALTHEX))
flags &= ~FL_ALT;
}
}
if (flags & FL_ALT) {
if (buf[c-1] == '0') {
flags &= ~(FL_ALT | FL_ALTHEX | FL_ALTUPP);
} else {
len += 1;
if (flags & FL_ALTHEX)
len += 1;
}
} else if (flags & (FL_NEGATIVE | FL_PLUS | FL_SPACE)) {
len += 1;
}
if (!(flags & FL_LPAD)) {
if (flags & FL_ZFILL) {
prec = c;
if (len < width) {
prec += width - len;
len = width;
}
}
while (len < width) {
putc (' ', stream);
len++;
}
}
width = (len < width) ? width - len : 0;
if (flags & FL_ALT) {
putc ('0', stream);
if (flags & FL_ALTHEX)
putc (flags & FL_ALTUPP ? 'X' : 'x', stream);
} else if (flags & (FL_NEGATIVE | FL_PLUS | FL_SPACE)) {
unsigned char z = ' ';
if (flags & FL_PLUS) z = '+';
if (flags & FL_NEGATIVE) z = '-';
putc (z, stream);
}
while (prec > c) {
putc ('0', stream);
prec--;
}
do {
putc (buf[--c], stream);
} while (c);
}
tail:
/* Tail is possible. */
while (width) {
putc (' ', stream);
width--;
}
} /* for (;;) */
ret:
return stream->len;
}
#endif /* PRINTF_LEVEL > PRINTF_MIN */
#endif /* !defined(__AVR_TINY__) */
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