615 lines
13 KiB
C
615 lines
13 KiB
C
/*
|
|
* /src/NTP/ntp4-dev/libntp/ieee754io.c,v 4.12 2005/04/16 17:32:10 kardel RELEASE_20050508_A
|
|
*
|
|
* ieee754io.c,v 4.12 2005/04/16 17:32:10 kardel RELEASE_20050508_A
|
|
*
|
|
* $Created: Sun Jul 13 09:12:02 1997 $
|
|
*
|
|
* Copyright (c) 1997-2005 by Frank Kardel <kardel <AT> ntp.org>
|
|
*
|
|
* 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 author 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 AUTHOR 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 AUTHOR 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.
|
|
*
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#include "l_stdlib.h"
|
|
#include "ntp_stdlib.h"
|
|
#include "ntp_fp.h"
|
|
#include "ieee754io.h"
|
|
|
|
static unsigned char get_byte (unsigned char *, offsets_t, int *);
|
|
#ifdef __not_yet__
|
|
static void put_byte (unsigned char *, offsets_t, int *, unsigned char);
|
|
#endif
|
|
|
|
#ifdef LIBDEBUG
|
|
|
|
#include "lib_strbuf.h"
|
|
|
|
static char *
|
|
fmt_blong(
|
|
unsigned long val,
|
|
int cnt
|
|
)
|
|
{
|
|
char *buf, *s;
|
|
int i = cnt;
|
|
|
|
val <<= 32 - cnt;
|
|
LIB_GETBUF(buf);
|
|
s = buf;
|
|
|
|
while (i--)
|
|
{
|
|
if (val & 0x80000000)
|
|
{
|
|
*s++ = '1';
|
|
}
|
|
else
|
|
{
|
|
*s++ = '0';
|
|
}
|
|
val <<= 1;
|
|
}
|
|
*s = '\0';
|
|
return buf;
|
|
}
|
|
|
|
static char *
|
|
fmt_flt(
|
|
unsigned int sign,
|
|
unsigned long mh,
|
|
unsigned long ml,
|
|
unsigned long ch
|
|
)
|
|
{
|
|
char *buf;
|
|
|
|
LIB_GETBUF(buf);
|
|
snprintf(buf, LIB_BUFLENGTH, "%c %s %s %s", sign ? '-' : '+',
|
|
fmt_blong(ch, 11),
|
|
fmt_blong(mh, 20),
|
|
fmt_blong(ml, 32));
|
|
|
|
return buf;
|
|
}
|
|
|
|
static char *
|
|
fmt_hex(
|
|
unsigned char *bufp,
|
|
int length
|
|
)
|
|
{
|
|
char * buf;
|
|
char hex[4];
|
|
int i;
|
|
|
|
LIB_GETBUF(buf);
|
|
buf[0] = '\0';
|
|
for (i = 0; i < length; i++) {
|
|
snprintf(hex, sizeof(hex), "%02x", bufp[i]);
|
|
strlcat(buf, hex, LIB_BUFLENGTH);
|
|
}
|
|
|
|
return buf;
|
|
}
|
|
|
|
#endif
|
|
|
|
static unsigned char
|
|
get_byte(
|
|
unsigned char *bufp,
|
|
offsets_t offset,
|
|
int *fieldindex
|
|
)
|
|
{
|
|
unsigned char val;
|
|
|
|
val = *(bufp + offset[*fieldindex]);
|
|
#ifdef LIBDEBUG
|
|
if (debug > 4)
|
|
printf("fetchieee754: getbyte(0x%08x, %d) = 0x%02x\n", (unsigned int)(bufp)+offset[*fieldindex], *fieldindex, val);
|
|
#endif
|
|
(*fieldindex)++;
|
|
return val;
|
|
}
|
|
|
|
#ifdef __not_yet__
|
|
static void
|
|
put_byte(
|
|
unsigned char *bufp,
|
|
offsets_t offsets,
|
|
int *fieldindex,
|
|
unsigned char val
|
|
)
|
|
{
|
|
*(bufp + offsets[*fieldindex]) = val;
|
|
(*fieldindex)++;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* make conversions to and from external IEEE754 formats and internal
|
|
* NTP FP format.
|
|
*/
|
|
int
|
|
fetch_ieee754(
|
|
unsigned char **buffpp,
|
|
int size,
|
|
l_fp *lfpp,
|
|
offsets_t offsets
|
|
)
|
|
{
|
|
unsigned char *bufp = *buffpp;
|
|
unsigned int sign;
|
|
unsigned int bias;
|
|
unsigned int maxexp;
|
|
int mbits;
|
|
u_long mantissa_low;
|
|
u_long mantissa_high;
|
|
u_long characteristic;
|
|
long exponent;
|
|
#ifdef LIBDEBUG
|
|
int length;
|
|
#endif
|
|
unsigned char val;
|
|
int fieldindex = 0;
|
|
|
|
switch (size)
|
|
{
|
|
case IEEE_DOUBLE:
|
|
#ifdef LIBDEBUG
|
|
length = 8;
|
|
#endif
|
|
mbits = 52;
|
|
bias = 1023;
|
|
maxexp = 2047;
|
|
break;
|
|
|
|
case IEEE_SINGLE:
|
|
#ifdef LIBDEBUG
|
|
length = 4;
|
|
#endif
|
|
mbits = 23;
|
|
bias = 127;
|
|
maxexp = 255;
|
|
break;
|
|
|
|
default:
|
|
return IEEE_BADCALL;
|
|
}
|
|
|
|
val = get_byte(bufp, offsets, &fieldindex); /* fetch sign byte & first part of characteristic */
|
|
|
|
sign = (val & 0x80) != 0;
|
|
characteristic = (val & 0x7F);
|
|
|
|
val = get_byte(bufp, offsets, &fieldindex); /* fetch rest of characteristic and start of mantissa */
|
|
|
|
switch (size)
|
|
{
|
|
case IEEE_SINGLE:
|
|
characteristic <<= 1;
|
|
characteristic |= (val & 0x80) != 0; /* grab last characteristic bit */
|
|
|
|
mantissa_high = 0;
|
|
|
|
mantissa_low = (val &0x7F) << 16;
|
|
mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
|
|
mantissa_low |= get_byte(bufp, offsets, &fieldindex);
|
|
break;
|
|
|
|
case IEEE_DOUBLE:
|
|
characteristic <<= 4;
|
|
characteristic |= (val & 0xF0) >> 4; /* grab lower characteristic bits */
|
|
|
|
mantissa_high = (val & 0x0F) << 16;
|
|
mantissa_high |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
|
|
mantissa_high |= get_byte(bufp, offsets, &fieldindex);
|
|
|
|
mantissa_low = (u_long)get_byte(bufp, offsets, &fieldindex) << 24;
|
|
mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 16;
|
|
mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
|
|
mantissa_low |= get_byte(bufp, offsets, &fieldindex);
|
|
break;
|
|
|
|
default:
|
|
return IEEE_BADCALL;
|
|
}
|
|
#ifdef LIBDEBUG
|
|
if (debug > 4)
|
|
{
|
|
double d;
|
|
float f;
|
|
|
|
if (size == IEEE_SINGLE)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < length; i++)
|
|
{
|
|
*((unsigned char *)(&f)+i) = *(*buffpp + offsets[i]);
|
|
}
|
|
d = f;
|
|
}
|
|
else
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < length; i++)
|
|
{
|
|
*((unsigned char *)(&d)+i) = *(*buffpp + offsets[i]);
|
|
}
|
|
}
|
|
|
|
printf("fetchieee754: FP: %s -> %s -> %e(=%s)\n", fmt_hex(*buffpp, length),
|
|
fmt_flt(sign, mantissa_high, mantissa_low, characteristic),
|
|
d, fmt_hex((unsigned char *)&d, length));
|
|
}
|
|
#endif
|
|
|
|
*buffpp += fieldindex;
|
|
|
|
/*
|
|
* detect funny numbers
|
|
*/
|
|
if (characteristic == maxexp)
|
|
{
|
|
/*
|
|
* NaN or Infinity
|
|
*/
|
|
if (mantissa_low || mantissa_high)
|
|
{
|
|
/*
|
|
* NaN
|
|
*/
|
|
return IEEE_NAN;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* +Inf or -Inf
|
|
*/
|
|
return sign ? IEEE_NEGINFINITY : IEEE_POSINFINITY;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* collect real numbers
|
|
*/
|
|
|
|
L_CLR(lfpp);
|
|
|
|
/*
|
|
* check for overflows
|
|
*/
|
|
exponent = characteristic - bias;
|
|
|
|
if (exponent > 31) /* sorry - hardcoded */
|
|
{
|
|
/*
|
|
* overflow only in respect to NTP-FP representation
|
|
*/
|
|
return sign ? IEEE_NEGOVERFLOW : IEEE_POSOVERFLOW;
|
|
}
|
|
else
|
|
{
|
|
int frac_offset; /* where the fraction starts */
|
|
|
|
frac_offset = mbits - exponent;
|
|
|
|
if (characteristic == 0)
|
|
{
|
|
/*
|
|
* de-normalized or tiny number - fits only as 0
|
|
*/
|
|
return IEEE_OK;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* adjust for implied 1
|
|
*/
|
|
if (mbits > 31)
|
|
mantissa_high |= 1 << (mbits - 32);
|
|
else
|
|
mantissa_low |= 1 << mbits;
|
|
|
|
/*
|
|
* take mantissa apart - if only all machine would support
|
|
* 64 bit operations 8-(
|
|
*/
|
|
if (frac_offset > mbits)
|
|
{
|
|
lfpp->l_ui = 0; /* only fractional number */
|
|
frac_offset -= mbits + 1; /* will now contain right shift count - 1*/
|
|
if (mbits > 31)
|
|
{
|
|
lfpp->l_uf = mantissa_high << (63 - mbits);
|
|
lfpp->l_uf |= mantissa_low >> (mbits - 33);
|
|
lfpp->l_uf >>= frac_offset;
|
|
}
|
|
else
|
|
{
|
|
lfpp->l_uf = mantissa_low >> frac_offset;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (frac_offset > 32)
|
|
{
|
|
/*
|
|
* must split in high word
|
|
*/
|
|
lfpp->l_ui = mantissa_high >> (frac_offset - 32);
|
|
lfpp->l_uf = (mantissa_high & ((1 << (frac_offset - 32)) - 1)) << (64 - frac_offset);
|
|
lfpp->l_uf |= mantissa_low >> (frac_offset - 32);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* must split in low word
|
|
*/
|
|
lfpp->l_ui = mantissa_high << (32 - frac_offset);
|
|
lfpp->l_ui |= (mantissa_low >> frac_offset) & ((1 << (32 - frac_offset)) - 1);
|
|
lfpp->l_uf = (mantissa_low & ((1 << frac_offset) - 1)) << (32 - frac_offset);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* adjust for sign
|
|
*/
|
|
if (sign)
|
|
{
|
|
L_NEG(lfpp);
|
|
}
|
|
|
|
return IEEE_OK;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
int
|
|
put_ieee754(
|
|
unsigned char **bufpp,
|
|
int size,
|
|
l_fp *lfpp,
|
|
offsets_t offsets
|
|
)
|
|
{
|
|
l_fp outlfp;
|
|
#ifdef LIBDEBUG
|
|
unsigned int sign;
|
|
unsigned int bias;
|
|
#endif
|
|
/*unsigned int maxexp;*/
|
|
int mbits;
|
|
int msb;
|
|
u_long mantissa_low = 0;
|
|
u_long mantissa_high = 0;
|
|
#ifdef LIBDEBUG
|
|
u_long characteristic = 0;
|
|
long exponent;
|
|
#endif
|
|
/*int length;*/
|
|
unsigned long mask;
|
|
|
|
outlfp = *lfpp;
|
|
|
|
switch (size)
|
|
{
|
|
case IEEE_DOUBLE:
|
|
/*length = 8;*/
|
|
mbits = 52;
|
|
#ifdef LIBDEBUG
|
|
bias = 1023;
|
|
#endif
|
|
/*maxexp = 2047;*/
|
|
break;
|
|
|
|
case IEEE_SINGLE:
|
|
/*length = 4;*/
|
|
mbits = 23;
|
|
#ifdef LIBDEBUG
|
|
bias = 127;
|
|
#endif
|
|
/*maxexp = 255;*/
|
|
break;
|
|
|
|
default:
|
|
return IEEE_BADCALL;
|
|
}
|
|
|
|
/*
|
|
* find sign
|
|
*/
|
|
if (L_ISNEG(&outlfp))
|
|
{
|
|
L_NEG(&outlfp);
|
|
#ifdef LIBDEBUG
|
|
sign = 1;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef LIBDEBUG
|
|
sign = 0;
|
|
#endif
|
|
}
|
|
|
|
if (L_ISZERO(&outlfp))
|
|
{
|
|
#ifdef LIBDEBUG
|
|
exponent = mantissa_high = mantissa_low = 0; /* true zero */
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* find number of significant integer bits
|
|
*/
|
|
mask = 0x80000000;
|
|
if (outlfp.l_ui)
|
|
{
|
|
msb = 63;
|
|
while (mask && ((outlfp.l_ui & mask) == 0))
|
|
{
|
|
mask >>= 1;
|
|
msb--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
msb = 31;
|
|
while (mask && ((outlfp.l_uf & mask) == 0))
|
|
{
|
|
mask >>= 1;
|
|
msb--;
|
|
}
|
|
}
|
|
|
|
switch (size)
|
|
{
|
|
case IEEE_SINGLE:
|
|
mantissa_high = 0;
|
|
if (msb >= 32)
|
|
{
|
|
mantissa_low = (outlfp.l_ui & ((1 << (msb - 32)) - 1)) << (mbits - (msb - 32));
|
|
mantissa_low |= outlfp.l_uf >> (mbits - (msb - 32));
|
|
}
|
|
else
|
|
{
|
|
mantissa_low = (outlfp.l_uf << (mbits - msb)) & ((1 << mbits) - 1);
|
|
}
|
|
break;
|
|
|
|
case IEEE_DOUBLE:
|
|
if (msb >= 32)
|
|
{
|
|
mantissa_high = (outlfp.l_ui << (mbits - msb)) & ((1 << (mbits - 32)) - 1);
|
|
mantissa_high |= outlfp.l_uf >> (32 - (mbits - msb));
|
|
mantissa_low = (outlfp.l_ui & ((1 << (msb - mbits)) - 1)) << (32 - (msb - mbits));
|
|
mantissa_low |= outlfp.l_uf >> (msb - mbits);
|
|
}
|
|
else
|
|
{
|
|
mantissa_high = outlfp.l_uf << (mbits - 32 - msb);
|
|
mantissa_low = outlfp.l_uf << (mbits - 32);
|
|
}
|
|
}
|
|
|
|
#ifdef LIBDEBUG
|
|
exponent = msb - 32;
|
|
characteristic = exponent + bias;
|
|
|
|
if (debug > 4)
|
|
printf("FP: %s\n", fmt_flt(sign, mantissa_high, mantissa_low, characteristic));
|
|
#endif
|
|
}
|
|
return IEEE_OK;
|
|
}
|
|
|
|
|
|
#if defined(DEBUG) && defined(LIBDEBUG)
|
|
int main(
|
|
int argc,
|
|
char **argv
|
|
)
|
|
{
|
|
static offsets_t native_off = { 0, 1, 2, 3, 4, 5, 6, 7 };
|
|
double f = 1.0;
|
|
double *f_p = &f;
|
|
l_fp fp;
|
|
|
|
if (argc == 2)
|
|
{
|
|
if (sscanf(argv[1], "%lf", &f) != 1)
|
|
{
|
|
printf("cannot convert %s to a float\n", argv[1]);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
printf("double: %s %s\n", fmt_blong(*(unsigned long *)&f, 32), fmt_blong(*(unsigned long *)((char *)(&f)+4), 32));
|
|
printf("fetch from %f = %d\n", f, fetch_ieee754((void *)&f_p, IEEE_DOUBLE, &fp, native_off));
|
|
printf("fp [%s %s] = %s\n", fmt_blong(fp.l_ui, 32), fmt_blong(fp.l_uf, 32), mfptoa(fp.l_ui, fp.l_uf, 15));
|
|
f_p = &f;
|
|
put_ieee754((void *)&f_p, IEEE_DOUBLE, &fp, native_off);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
/*
|
|
* History:
|
|
*
|
|
* ieee754io.c,v
|
|
* Revision 4.12 2005/04/16 17:32:10 kardel
|
|
* update copyright
|
|
*
|
|
* Revision 4.11 2004/11/14 15:29:41 kardel
|
|
* support PPSAPI, upgrade Copyright to Berkeley style
|
|
*
|
|
* Revision 4.8 1999/02/21 12:17:36 kardel
|
|
* 4.91f reconcilation
|
|
*
|
|
* Revision 4.7 1999/02/21 11:26:03 kardel
|
|
* renamed index to fieldindex to avoid index() name clash
|
|
*
|
|
* Revision 4.6 1998/11/15 20:27:52 kardel
|
|
* Release 4.0.73e13 reconcilation
|
|
*
|
|
* Revision 4.5 1998/08/16 19:01:51 kardel
|
|
* debug information only compile for LIBDEBUG case
|
|
*
|
|
* Revision 4.4 1998/08/09 09:39:28 kardel
|
|
* Release 4.0.73e2 reconcilation
|
|
*
|
|
* Revision 4.3 1998/06/13 11:56:19 kardel
|
|
* disabled putbute() for the time being
|
|
*
|
|
* Revision 4.2 1998/06/12 15:16:58 kardel
|
|
* ansi2knr compatibility
|
|
*
|
|
* Revision 4.1 1998/05/24 07:59:56 kardel
|
|
* conditional debug support
|
|
*
|
|
* Revision 4.0 1998/04/10 19:46:29 kardel
|
|
* Start 4.0 release version numbering
|
|
*
|
|
* Revision 1.1 1998/04/10 19:27:46 kardel
|
|
* initial NTP VERSION 4 integration of PARSE with GPS166 binary support
|
|
*
|
|
* Revision 1.1 1997/10/06 21:05:45 kardel
|
|
* new parse structure
|
|
*
|
|
*/
|