
/*
 * 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 "config.h"
#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 "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

#if defined(__linux__)
#include <bits/endian.h>
#elif defined(_WIN32)
/* XXX */
#elif defined(__APPLE__)
#include <sys/_endian.h>
#else
#include <sys/endian.h>
#endif
#define IEEEFP

#endif				/* vax */

bool
xdr_float(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
xdr_double(XDR *xdrs, double *dp)
{
#ifdef IEEEFP
	int32_t *i32p;
	bool 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);
}
