xdr_float.c revision 7f93f875323d3870ccfa2f3df6aad7f2edecbafe
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Portions of this source code were derived from Berkeley
* 4.3 BSD under license from the Regents of the University of
* California.
*/
/*
* Copyright 2011 Jason King. All rights reserved
*/
/*
* Generic XDR routines impelmentation.
*
* These are the "floating point" xdr routines used to (de)serialize
* most common data items. See xdr.h for more info on the interface to
* xdr.
*/
#include "mt.h"
#include <sys/types.h>
#include <stdio.h>
#include <values.h>
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <sys/byteorder.h>
#ifdef _IEEE_754
/*
* The OTW format is IEEE 754 with big endian ordering.
*/
bool_t
xdr_float(XDR *xdrs, float *fp)
{
switch (xdrs->x_op) {
case XDR_ENCODE:
return (XDR_PUTINT32(xdrs, (int *)fp));
case XDR_DECODE:
return (XDR_GETINT32(xdrs, (int *)fp));
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}
bool_t
xdr_double(XDR *xdrs, double *dp)
{
int64_t *i64p = (int64_t *)dp;
int64_t val;
bool_t ret;
switch (xdrs->x_op) {
case XDR_ENCODE:
val = BE_64(*i64p);
return (XDR_PUTBYTES(xdrs, (char *)&val, sizeof (val)));
case XDR_DECODE:
ret = XDR_GETBYTES(xdrs, (char *)dp, sizeof (double));
if (ret)
*i64p = BE_64(*i64p);
return (ret);
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}
/* ARGSUSED */
bool_t
xdr_quadruple(XDR *xdrs, long double *fp)
{
/*
* The Sparc uses IEEE FP encoding, so just do a byte copy
*/
#if !defined(sparc)
return (FALSE);
#else
switch (xdrs->x_op) {
case XDR_ENCODE:
return (XDR_PUTBYTES(xdrs, (char *)fp, sizeof (long double)));
case XDR_DECODE:
return (XDR_GETBYTES(xdrs, (char *)fp, sizeof (long double)));
case XDR_FREE:
return (TRUE);
}
return (FALSE);
#endif
}
#else
#warn No platform specific implementation defined for floats
bool_t
xdr_float(XDR *xdrs, float *fp)
{
/*
* Every machine can do this, its just not very efficient.
* In addtion, some rounding errors may occur do to the
* calculations involved.
*/
float f;
int neg = 0;
int exp = 0;
int32_t val;
switch (xdrs->x_op) {
case XDR_ENCODE:
f = *fp;
if (f == 0) {
val = 0;
return (XDR_PUTINT32(xdrs, &val));
}
if (f < 0) {
f = 0 - f;
neg = 1;
}
while (f < 1) {
f = f * 2;
--exp;
}
while (f >= 2) {
f = f/2;
++exp;
}
if ((exp > 128) || (exp < -127)) {
/* over or under flowing ieee exponent */
return (FALSE);
}
val = neg;
val = val << 8; /* for the exponent */
val += 127 + exp; /* 127 is the bias */
val = val << 23; /* for the mantissa */
val += (int32_t)((f - 1) * 8388608); /* 2 ^ 23 */
return (XDR_PUTINT32(xdrs, &val));
case XDR_DECODE:
/*
* It assumes that the decoding machine's float can represent
* any value in the range of
* ieee largest float = (2 ^ 128) * 0x1.fffff
* to
* ieee smallest float = (2 ^ -127) * 0x1.00000
* In addtion, some rounding errors may occur do to the
* calculations involved.
*/
if (!XDR_GETINT32(xdrs, (int32_t *)&val))
return (FALSE);
neg = val & 0x80000000;
exp = (val & 0x7f800000) >> 23;
exp -= 127; /* subtract exponent base */
f = (val & 0x007fffff) * 0.00000011920928955078125;
/* 2 ^ -23 */
f++;
while (exp != 0) {
if (exp < 0) {
f = f/2.0;
++exp;
} else {
f = f * 2.0;
--exp;
}
}
if (neg)
f = 0 - f;
*fp = f;
return (TRUE);
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}
bool_t
xdr_double(XDR *xdrs, double *dp)
{
/*
* Every machine can do this, its just not very efficient.
* In addtion, some rounding errors may occur do to the
* calculations involved.
*/
int *lp;
double d;
int neg = 0;
int exp = 0;
int32_t val[2];
switch (xdrs->x_op) {
case XDR_ENCODE:
d = *dp;
if (d == 0) {
val[0] = 0;
val[1] = 0;
lp = val;
return (XDR_PUTINT32(xdrs, lp++) &&
XDR_PUTINT32(xdrs, lp));
}
if (d < 0) {
d = 0 - d;
neg = 1;
}
while (d < 1) {
d = d * 2;
--exp;
}
while (d >= 2) {
d = d/2;
++exp;
}
if ((exp > 1024) || (exp < -1023)) {
/* over or under flowing ieee exponent */
return (FALSE);
}
val[0] = (neg << 11); /* for the exponent */
val[0] += 1023 + exp; /* 1023 is the bias */
val[0] = val[0] << 20; /* for the mantissa */
val[0] += (int32_t)((d - 1) * 1048576); /* 2 ^ 20 */
val[1] += (uint32_t)((((d - 1) * 1048576) - val[0]) *
4294967296); /* 2 ^ 32 */
lp = val;
return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
case XDR_DECODE:
/*
* It assumes that the decoding machine's
* double can represent any value in the range of
* ieee largest double = (2 ^ 1024) * 0x1.fffffffffffff
* to
* ieee smallest double = (2 ^ -1023) * 0x1.0000000000000
* In addtion, some rounding errors may occur do to the
* calculations involved.
*/
lp = val;
if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
return (FALSE);
neg = val[0] & 0x80000000;
exp = (val[0] & 0x7ff00000) >> 20;
exp -= 1023; /* subtract exponent base */
d = (val[0] & 0x000fffff) * 0.00000095367431640625;
/* 2 ^ -20 */
d += (val[1] * 0.0000000000000002220446049250313);
/* 2 ^ -52 */
d++;
while (exp != 0) {
if (exp < 0) {
d = d/2.0;
++exp;
} else {
d = d * 2.0;
--exp;
}
}
if (neg)
d = 0 - d;
*dp = d;
return (TRUE);
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}
bool_t
xdr_quadruple(XDR *xdrs, long double *fp)
{
return (FALSE);
}
#endif /* _IEEE_754 */