BSD 4_3_Reno release
[unix-history] / usr / src / lib / librpc / xdr_float.c
/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#ifndef lint
static char sccsid[] = "@(#)xdr_float.c 1.2 85/03/14 Copyr 1984 Sun Micro";
#endif
/*
* xdr_float.c, Generic XDR routines impelmentation.
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*
* 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 "types.h"
#include "xdr.h"
#include <stdio.h>
/*
* NB: Not portable.
* This routine works on Suns (Sky / 68000's) and Vaxen.
*/
/* What IEEE single precision floating point looks like on a Vax */
struct ieee_single {
unsigned int mantissa: 23;
unsigned int exp : 8;
unsigned int sign : 1;
};
/* Vax single precision floating point */
struct vax_single {
unsigned int mantissa1 : 7;
unsigned int exp : 8;
unsigned int sign : 1;
unsigned int mantissa2 : 16;
};
#define VAX_SNG_BIAS 0x81
#define IEEE_SNG_BIAS 0x7f
static struct sgl_limits {
struct vax_single s;
struct ieee_single ieee;
} sgl_limits[2] = {
{{ 0x3f, 0xff, 0x0, 0xffff }, /* Max Vax */
{ 0x0, 0xff, 0x0 }}, /* Max IEEE */
{{ 0x0, 0x0, 0x0, 0x0 }, /* Min Vax */
{ 0x0, 0x0, 0x0 }} /* Min IEEE */
};
bool_t
xdr_float(xdrs, fp)
register XDR *xdrs;
register float *fp;
{
struct ieee_single is;
struct vax_single vs, *vsp;
struct sgl_limits *lim;
int i;
switch (xdrs->x_op) {
case XDR_ENCODE:
#ifdef mc68000
return (XDR_PUTLONG(xdrs, (long *)fp));
#else
vs = *((struct vax_single *)fp);
for (i = 0, lim = sgl_limits;
i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
i++, lim++) {
if ((vs.mantissa2 == lim->s.mantissa2) &&
(vs.exp == lim->s.exp) &&
(vs.mantissa1 == lim->s.mantissa1)) {
is = lim->ieee;
goto shipit;
}
}
is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
shipit:
is.sign = vs.sign;
return (XDR_PUTLONG(xdrs, (long *)&is));
#endif
case XDR_DECODE:
#ifdef mc68000
return (XDR_GETLONG(xdrs, (long *)fp));
#else
vsp = (struct vax_single *)fp;
if (!XDR_GETLONG(xdrs, (long *)&is))
return (FALSE);
for (i = 0, lim = sgl_limits;
i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
i++, lim++) {
if ((is.exp == lim->ieee.exp) &&
(is.mantissa = lim->ieee.mantissa)) {
*vsp = lim->s;
goto doneit;
}
}
vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
vsp->mantissa2 = is.mantissa;
vsp->mantissa1 = (is.mantissa >> 16);
doneit:
vsp->sign = is.sign;
return (TRUE);
#endif
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}
/*
* This routine works on Suns (Sky / 68000's) and Vaxen.
*/
/* What IEEE double precision floating point looks like on a Vax */
struct ieee_double {
unsigned int mantissa1 : 20;
unsigned int exp : 11;
unsigned int sign : 1;
unsigned int mantissa2 : 32;
};
/* Vax double precision floating point */
struct vax_double {
unsigned int mantissa1 : 7;
unsigned int exp : 8;
unsigned int sign : 1;
unsigned int mantissa2 : 16;
unsigned int mantissa3 : 16;
unsigned int mantissa4 : 16;
};
#define VAX_DBL_BIAS 0x81
#define IEEE_DBL_BIAS 0x3ff
#define MASK(nbits) ((1 << nbits) - 1)
static struct dbl_limits {
struct vax_double d;
struct ieee_double ieee;
} dbl_limits[2] = {
{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff }, /* Max Vax */
{ 0x0, 0x7ff, 0x0, 0x0 }}, /* Max IEEE */
{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, /* Min Vax */
{ 0x0, 0x0, 0x0, 0x0 }} /* Min IEEE */
};
bool_t
xdr_double(xdrs, dp)
register XDR *xdrs;
double *dp;
{
register long *lp;
struct ieee_double id;
struct vax_double vd;
register struct dbl_limits *lim;
int i;
switch (xdrs->x_op) {
case XDR_ENCODE:
#ifdef mc68000
lp = (long *)dp;
#else
vd = *((struct vax_double *)dp);
for (i = 0, lim = dbl_limits;
i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
i++, lim++) {
if ((vd.mantissa4 == lim->d.mantissa4) &&
(vd.mantissa3 == lim->d.mantissa3) &&
(vd.mantissa2 == lim->d.mantissa2) &&
(vd.mantissa1 == lim->d.mantissa1) &&
(vd.exp == lim->d.exp)) {
id = lim->ieee;
goto shipit;
}
}
id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
(vd.mantissa3 << 13) |
((vd.mantissa4 >> 3) & MASK(13));
shipit:
id.sign = vd.sign;
lp = (long *)&id;
#endif
return (XDR_PUTLONG(xdrs, lp++) && XDR_PUTLONG(xdrs, lp));
case XDR_DECODE:
#ifdef mc68000
lp = (long *)dp;
return (XDR_GETLONG(xdrs, lp++) && XDR_GETLONG(xdrs, lp));
#else
lp = (long *)&id;
if (!XDR_GETLONG(xdrs, lp++) || !XDR_GETLONG(xdrs, lp))
return (FALSE);
for (i = 0, lim = dbl_limits;
i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
i++, lim++) {
if ((id.mantissa2 == lim->ieee.mantissa2) &&
(id.mantissa1 == lim->ieee.mantissa1) &&
(id.exp == lim->ieee.exp)) {
vd = lim->d;
goto doneit;
}
}
vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
vd.mantissa1 = (id.mantissa1 >> 13);
vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
(id.mantissa2 >> 29);
vd.mantissa3 = (id.mantissa2 >> 13);
vd.mantissa4 = (id.mantissa2 << 3);
doneit:
vd.sign = id.sign;
*dp = *((double *)&vd);
return (TRUE);
#endif
case XDR_FREE:
return (TRUE);
}
return (FALSE);
}