xref: /freebsd/lib/libc/xdr/xdr_float.c (revision a3cbca537ef1d8ac03a693cd51d98fb8087acc8d)
1 /*	$NetBSD: xdr_float.c,v 1.23 2000/07/17 04:59:51 matt Exp $	*/
2 
3 /*-
4  * Copyright (c) 2010, Oracle America, Inc.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are
8  * met:
9  *
10  *     * Redistributions of source code must retain the above copyright
11  *       notice, this list of conditions and the following disclaimer.
12  *     * Redistributions in binary form must reproduce the above
13  *       copyright notice, this list of conditions and the following
14  *       disclaimer in the documentation and/or other materials
15  *       provided with the distribution.
16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
17  *       contributors may be used to endorse or promote products derived
18  *       from this software without specific prior written permission.
19  *
20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char *sccsid2 = "@(#)xdr_float.c 1.12 87/08/11 Copyr 1984 Sun Micro";
36 static char *sccsid = "@(#)xdr_float.c	2.1 88/07/29 4.0 RPCSRC";
37 #endif
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 /*
42  * xdr_float.c, Generic XDR routines implementation.
43  *
44  * These are the "floating point" xdr routines used to (de)serialize
45  * most common data items.  See xdr.h for more info on the interface to
46  * xdr.
47  */
48 
49 #include "namespace.h"
50 #include <sys/types.h>
51 #include <sys/param.h>
52 
53 #include <stdio.h>
54 
55 #include <rpc/types.h>
56 #include <rpc/xdr.h>
57 #include "un-namespace.h"
58 
59 /*
60  * NB: Not portable.
61  * This routine works on machines with IEEE754 FP and Vaxen.
62  */
63 
64 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
65     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
66     defined(__arm__) || defined(__ppc__) || \
67     defined(__arm26__) || defined(__sparc64__) || defined(__amd64__)
68 #include <machine/endian.h>
69 #define IEEEFP
70 #endif
71 
72 #if defined(__vax__)
73 
74 /* What IEEE single precision floating point looks like on a Vax */
75 struct	ieee_single {
76 	unsigned int	mantissa: 23;
77 	unsigned int	exp     : 8;
78 	unsigned int	sign    : 1;
79 };
80 
81 /* Vax single precision floating point */
82 struct	vax_single {
83 	unsigned int	mantissa1 : 7;
84 	unsigned int	exp       : 8;
85 	unsigned int	sign      : 1;
86 	unsigned int	mantissa2 : 16;
87 };
88 
89 #define VAX_SNG_BIAS	0x81
90 #define IEEE_SNG_BIAS	0x7f
91 
92 static struct sgl_limits {
93 	struct vax_single s;
94 	struct ieee_single ieee;
95 } sgl_limits[2] = {
96 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
97 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
98 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
99 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
100 };
101 #endif /* vax */
102 
103 bool_t
104 xdr_float(xdrs, fp)
105 	XDR *xdrs;
106 	float *fp;
107 {
108 #ifndef IEEEFP
109 	struct ieee_single is;
110 	struct vax_single vs, *vsp;
111 	struct sgl_limits *lim;
112 	int i;
113 #endif
114 	switch (xdrs->x_op) {
115 
116 	case XDR_ENCODE:
117 #ifdef IEEEFP
118 		return (XDR_PUTINT32(xdrs, (int32_t *)fp));
119 #else
120 		vs = *((struct vax_single *)fp);
121 		for (i = 0, lim = sgl_limits;
122 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
123 			i++, lim++) {
124 			if ((vs.mantissa2 == lim->s.mantissa2) &&
125 				(vs.exp == lim->s.exp) &&
126 				(vs.mantissa1 == lim->s.mantissa1)) {
127 				is = lim->ieee;
128 				goto shipit;
129 			}
130 		}
131 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
132 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
133 	shipit:
134 		is.sign = vs.sign;
135 		return (XDR_PUTINT32(xdrs, (int32_t *)&is));
136 #endif
137 
138 	case XDR_DECODE:
139 #ifdef IEEEFP
140 		return (XDR_GETINT32(xdrs, (int32_t *)fp));
141 #else
142 		vsp = (struct vax_single *)fp;
143 		if (!XDR_GETINT32(xdrs, (int32_t *)&is))
144 			return (FALSE);
145 		for (i = 0, lim = sgl_limits;
146 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
147 			i++, lim++) {
148 			if ((is.exp == lim->ieee.exp) &&
149 				(is.mantissa == lim->ieee.mantissa)) {
150 				*vsp = lim->s;
151 				goto doneit;
152 			}
153 		}
154 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
155 		vsp->mantissa2 = is.mantissa;
156 		vsp->mantissa1 = (is.mantissa >> 16);
157 	doneit:
158 		vsp->sign = is.sign;
159 		return (TRUE);
160 #endif
161 
162 	case XDR_FREE:
163 		return (TRUE);
164 	}
165 	/* NOTREACHED */
166 	return (FALSE);
167 }
168 
169 #if defined(__vax__)
170 /* What IEEE double precision floating point looks like on a Vax */
171 struct	ieee_double {
172 	unsigned int	mantissa1 : 20;
173 	unsigned int	exp       : 11;
174 	unsigned int	sign      : 1;
175 	unsigned int	mantissa2 : 32;
176 };
177 
178 /* Vax double precision floating point */
179 struct  vax_double {
180 	unsigned int	mantissa1 : 7;
181 	unsigned int	exp       : 8;
182 	unsigned int	sign      : 1;
183 	unsigned int	mantissa2 : 16;
184 	unsigned int	mantissa3 : 16;
185 	unsigned int	mantissa4 : 16;
186 };
187 
188 #define VAX_DBL_BIAS	0x81
189 #define IEEE_DBL_BIAS	0x3ff
190 #define MASK(nbits)	((1 << nbits) - 1)
191 
192 static struct dbl_limits {
193 	struct	vax_double d;
194 	struct	ieee_double ieee;
195 } dbl_limits[2] = {
196 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
197 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
198 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
199 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
200 };
201 
202 #endif /* vax */
203 
204 
205 bool_t
206 xdr_double(xdrs, dp)
207 	XDR *xdrs;
208 	double *dp;
209 {
210 #ifdef IEEEFP
211 	int32_t *i32p;
212 	bool_t rv;
213 #else
214 	int32_t *lp;
215 	struct	ieee_double id;
216 	struct	vax_double vd;
217 	struct dbl_limits *lim;
218 	int i;
219 #endif
220 
221 	switch (xdrs->x_op) {
222 
223 	case XDR_ENCODE:
224 #ifdef IEEEFP
225 		i32p = (int32_t *)(void *)dp;
226 #if BYTE_ORDER == BIG_ENDIAN
227 		rv = XDR_PUTINT32(xdrs, i32p);
228 		if (!rv)
229 			return (rv);
230 		rv = XDR_PUTINT32(xdrs, i32p+1);
231 #else
232 		rv = XDR_PUTINT32(xdrs, i32p+1);
233 		if (!rv)
234 			return (rv);
235 		rv = XDR_PUTINT32(xdrs, i32p);
236 #endif
237 		return (rv);
238 #else
239 		vd = *((struct vax_double *)dp);
240 		for (i = 0, lim = dbl_limits;
241 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
242 			i++, lim++) {
243 			if ((vd.mantissa4 == lim->d.mantissa4) &&
244 				(vd.mantissa3 == lim->d.mantissa3) &&
245 				(vd.mantissa2 == lim->d.mantissa2) &&
246 				(vd.mantissa1 == lim->d.mantissa1) &&
247 				(vd.exp == lim->d.exp)) {
248 				id = lim->ieee;
249 				goto shipit;
250 			}
251 		}
252 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
253 		id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
254 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
255 				(vd.mantissa3 << 13) |
256 				((vd.mantissa4 >> 3) & MASK(13));
257 	shipit:
258 		id.sign = vd.sign;
259 		lp = (int32_t *)&id;
260 		return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
261 #endif
262 
263 	case XDR_DECODE:
264 #ifdef IEEEFP
265 		i32p = (int32_t *)(void *)dp;
266 #if BYTE_ORDER == BIG_ENDIAN
267 		rv = XDR_GETINT32(xdrs, i32p);
268 		if (!rv)
269 			return (rv);
270 		rv = XDR_GETINT32(xdrs, i32p+1);
271 #else
272 		rv = XDR_GETINT32(xdrs, i32p+1);
273 		if (!rv)
274 			return (rv);
275 		rv = XDR_GETINT32(xdrs, i32p);
276 #endif
277 		return (rv);
278 #else
279 		lp = (int32_t *)&id;
280 		if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
281 			return (FALSE);
282 		for (i = 0, lim = dbl_limits;
283 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
284 			i++, lim++) {
285 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
286 				(id.mantissa1 == lim->ieee.mantissa1) &&
287 				(id.exp == lim->ieee.exp)) {
288 				vd = lim->d;
289 				goto doneit;
290 			}
291 		}
292 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
293 		vd.mantissa1 = (id.mantissa1 >> 13);
294 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
295 				(id.mantissa2 >> 29);
296 		vd.mantissa3 = (id.mantissa2 >> 13);
297 		vd.mantissa4 = (id.mantissa2 << 3);
298 	doneit:
299 		vd.sign = id.sign;
300 		*dp = *((double *)&vd);
301 		return (TRUE);
302 #endif
303 
304 	case XDR_FREE:
305 		return (TRUE);
306 	}
307 	/* NOTREACHED */
308 	return (FALSE);
309 }
310