xdr_float.c

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/*
 * Copyright (c) 2009, Sun Microsystems, Inc.
 * 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 Sun Microsystems, Inc. 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 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 HOLDER 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.
 */
 
//#include <sys/cdefs.h>
 
/*
 * xdr_float.c, Generic XDR routines implementation.
 *
 * 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 <wintirpc.h>
#include "namespace.h"
#include <sys/types.h>
//#include <sys/param.h>
 
#include <stdio.h>
 
#include <rpc/types.h>
#include <rpc/xdr.h>
#include "un-namespace.h"
 
/*
 * NB: Not portable.
 * This routine works on machines with IEEE754 FP and Vaxen.
 */
 
#if defined(__vax__)
 
/* 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] = {
    {{ 0x7f, 0xff, 0x0, 0xffff },   /* Max Vax */
    { 0x0, 0xff, 0x0 }},        /* Max IEEE */
    {{ 0x0, 0x0, 0x0, 0x0 },    /* Min Vax */
    { 0x0, 0x0, 0x0 }}      /* Min IEEE */
};
#else
 
//#include <bits/endian.h>
#define IEEEFP
 
#endif /* vax */
 
bool_t
xdr_float(xdrs, fp)
    XDR *xdrs;
    float *fp;
{
#ifndef IEEEFP
    struct ieee_single is;
    struct vax_single vs, *vsp;
    struct sgl_limits *lim;
    int i;
#endif
    switch (xdrs->x_op) {
 
    case XDR_ENCODE:
#ifdef IEEEFP
        return (XDR_PUTINT32(xdrs, (int32_t *)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_PUTINT32(xdrs, (int32_t *)&is));
#endif
 
    case XDR_DECODE:
#ifdef IEEEFP
        return (XDR_GETINT32(xdrs, (int32_t *)fp));
#else
        vsp = (struct vax_single *)fp;
        if (!XDR_GETINT32(xdrs, (int32_t *)&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);
    }
    /* NOTREACHED */
    return (FALSE);
}
 
#if defined(__vax__)
/* 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 */
};
 
#endif /* vax */
 
 
bool_t
xdr_double(xdrs, dp)
    XDR *xdrs;
    double *dp;
{
#ifdef IEEEFP
    int32_t *i32p;
    bool_t rv;
#else
    int32_t *lp;
    struct  ieee_double id;
    struct  vax_double vd;
    struct dbl_limits *lim;
    int i;
#endif
 
    switch (xdrs->x_op) {
 
    case XDR_ENCODE:
#ifdef IEEEFP
        i32p = (int32_t *)(void *)dp;
#if BYTE_ORDER == BIG_ENDIAN
        rv = XDR_PUTINT32(xdrs, i32p);
        if (!rv)
            return (rv);
        rv = XDR_PUTINT32(xdrs, i32p+1);
#else
        rv = XDR_PUTINT32(xdrs, i32p+1);
        if (!rv)
            return (rv);
        rv = XDR_PUTINT32(xdrs, i32p);
#endif
        return (rv);
#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 = (int32_t *)&id;
        return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
#endif
 
    case XDR_DECODE:
#ifdef IEEEFP
        i32p = (int32_t *)(void *)dp;
#if BYTE_ORDER == BIG_ENDIAN
        rv = XDR_GETINT32(xdrs, i32p);
        if (!rv)
            return (rv);
        rv = XDR_GETINT32(xdrs, i32p+1);
#else
        rv = XDR_GETINT32(xdrs, i32p+1);
        if (!rv)
            return (rv);
        rv = XDR_GETINT32(xdrs, i32p);
#endif
        return (rv);
#else
        lp = (int32_t *)&id;
        if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(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);
    }
    /* NOTREACHED */
    return (FALSE);
}