xref: /netbsd-src/lib/libc/rpc/xdr_float.c (revision 4d12bfcd155352508213ace5ccc59ce930ea2974)
1 /*	$NetBSD: xdr_float.c,v 1.38 2013/03/11 20:19:29 tron 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 #include <sys/cdefs.h>
35 #if defined(LIBC_SCCS) && !defined(lint)
36 #if 0
37 static char *sccsid = "@(#)xdr_float.c 1.12 87/08/11 Copyr 1984 Sun Micro";
38 static char *sccsid = "@(#)xdr_float.c	2.1 88/07/29 4.0 RPCSRC";
39 #else
40 __RCSID("$NetBSD: xdr_float.c,v 1.38 2013/03/11 20:19:29 tron Exp $");
41 #endif
42 #endif
43 
44 /*
45  * xdr_float.c, Generic XDR routines implementation.
46  *
47  * Copyright (C) 1984, Sun Microsystems, Inc.
48  *
49  * These are the "floating point" xdr routines used to (de)serialize
50  * most common data items.  See xdr.h for more info on the interface to
51  * xdr.
52  */
53 
54 #include "namespace.h"
55 
56 #include <sys/types.h>
57 #include <sys/param.h>
58 
59 #include <stdio.h>
60 
61 #include <rpc/types.h>
62 #include <rpc/xdr.h>
63 
64 #ifdef __weak_alias
65 __weak_alias(xdr_double,_xdr_double)
66 __weak_alias(xdr_float,_xdr_float)
67 #endif
68 
69 /*
70  * NB: Not portable.
71  * This routine works on machines with IEEE754 FP and Vaxen.
72  */
73 
74 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
75     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
76     defined(__arm__) || defined(__powerpc__) || defined(__sh__) || \
77     defined(__x86_64__) || defined(__hppa__) || defined(__ia64__)
78 #include <machine/endian.h>
79 #define IEEEFP
80 #endif
81 
82 #if defined(__vax__)
83 
84 /* What IEEE single precision floating point looks like on a Vax */
85 struct	ieee_single {
86 	unsigned int	mantissa: 23;
87 	unsigned int	exp     : 8;
88 	unsigned int	sign    : 1;
89 };
90 
91 /* Vax single precision floating point */
92 struct	vax_single {
93 	unsigned int	mantissa1 : 7;
94 	unsigned int	exp       : 8;
95 	unsigned int	sign      : 1;
96 	unsigned int	mantissa2 : 16;
97 };
98 
99 #define VAX_SNG_BIAS	0x81
100 #define IEEE_SNG_BIAS	0x7f
101 
102 static struct sgl_limits {
103 	struct vax_single s;
104 	struct ieee_single ieee;
105 } sgl_limits[2] = {
106 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
107 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
108 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
109 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
110 };
111 #endif /* vax */
112 
113 bool_t
114 xdr_float(XDR *xdrs, float *fp)
115 {
116 #ifndef IEEEFP
117 	struct ieee_single is;
118 	struct vax_single vs, *vsp;
119 	struct sgl_limits *lim;
120 	size_t i;
121 #endif
122 	switch (xdrs->x_op) {
123 
124 	case XDR_ENCODE:
125 #ifdef IEEEFP
126 		return (XDR_PUTINT32(xdrs, (int32_t *)(void *)fp));
127 #else
128 		vs = *((struct vax_single *)(void *)fp);
129 		for (i = 0, lim = sgl_limits;
130 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
131 			i++, lim++) {
132 			if ((vs.mantissa2 == lim->s.mantissa2) &&
133 				(vs.exp == lim->s.exp) &&
134 				(vs.mantissa1 == lim->s.mantissa1)) {
135 				is = lim->ieee;
136 				goto shipit;
137 			}
138 		}
139 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
140 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
141 	shipit:
142 		is.sign = vs.sign;
143 		return (XDR_PUTINT32(xdrs, (int32_t *)(void *)&is));
144 #endif
145 
146 	case XDR_DECODE:
147 #ifdef IEEEFP
148 		return (XDR_GETINT32(xdrs, (int32_t *)(void *)fp));
149 #else
150 		vsp = (struct vax_single *)(void *)fp;
151 		if (!XDR_GETINT32(xdrs, (int32_t *)(void *)&is))
152 			return (FALSE);
153 		for (i = 0, lim = sgl_limits;
154 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
155 			i++, lim++) {
156 			if ((is.exp == lim->ieee.exp) &&
157 				(is.mantissa == lim->ieee.mantissa)) {
158 				*vsp = lim->s;
159 				goto doneit;
160 			}
161 		}
162 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
163 		vsp->mantissa2 = is.mantissa;
164 		vsp->mantissa1 = ((unsigned int)is.mantissa >> 16);
165 	doneit:
166 		vsp->sign = is.sign;
167 		return (TRUE);
168 #endif
169 
170 	case XDR_FREE:
171 		return (TRUE);
172 	}
173 	/* NOTREACHED */
174 	return (FALSE);
175 }
176 
177 #if defined(__vax__)
178 /* What IEEE double precision floating point looks like on a Vax */
179 struct	ieee_double {
180 	unsigned int	mantissa1 : 20;
181 	unsigned int	exp       : 11;
182 	unsigned int	sign      : 1;
183 	unsigned int	mantissa2 : 32;
184 };
185 
186 /* Vax double precision floating point */
187 struct  vax_double {
188 	unsigned int	mantissa1 : 7;
189 	unsigned int	exp       : 8;
190 	unsigned int	sign      : 1;
191 	unsigned int	mantissa2 : 16;
192 	unsigned int	mantissa3 : 16;
193 	unsigned int	mantissa4 : 16;
194 };
195 
196 #define VAX_DBL_BIAS	0x81
197 #define IEEE_DBL_BIAS	0x3ff
198 #define MASK(nbits)	((1 << nbits) - 1)
199 
200 static struct dbl_limits {
201 	struct	vax_double d;
202 	struct	ieee_double ieee;
203 } dbl_limits[2] = {
204 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
205 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
206 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
207 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
208 };
209 
210 #endif /* vax */
211 
212 
213 bool_t
214 xdr_double(XDR *xdrs, double *dp)
215 {
216 #ifdef IEEEFP
217 	int32_t *i32p;
218 	bool_t rv;
219 #else
220 	int32_t *lp;
221 	struct	ieee_double id;
222 	struct	vax_double vd;
223 	struct dbl_limits *lim;
224 	size_t i;
225 #endif
226 
227 	switch (xdrs->x_op) {
228 
229 	case XDR_ENCODE:
230 #ifdef IEEEFP
231 		i32p = (int32_t *)(void *)dp;
232 #if (BYTE_ORDER == BIG_ENDIAN) || \
233     (defined(__arm__) && !defined(__VFP_FP__))
234 		rv = XDR_PUTINT32(xdrs, i32p);
235 		if (!rv)
236 			return (rv);
237 		rv = XDR_PUTINT32(xdrs, i32p+1);
238 #else
239 		rv = XDR_PUTINT32(xdrs, i32p+1);
240 		if (!rv)
241 			return (rv);
242 		rv = XDR_PUTINT32(xdrs, i32p);
243 #endif
244 		return (rv);
245 #else
246 		vd = *((struct vax_double *)(void *)dp);
247 		for (i = 0, lim = dbl_limits;
248 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
249 			i++, lim++) {
250 			if ((vd.mantissa4 == lim->d.mantissa4) &&
251 				(vd.mantissa3 == lim->d.mantissa3) &&
252 				(vd.mantissa2 == lim->d.mantissa2) &&
253 				(vd.mantissa1 == lim->d.mantissa1) &&
254 				(vd.exp == lim->d.exp)) {
255 				id = lim->ieee;
256 				goto shipit;
257 			}
258 		}
259 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
260 		id.mantissa1 = (vd.mantissa1 << 13) |
261 			    ((unsigned int)vd.mantissa2 >> 3);
262 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
263 				(vd.mantissa3 << 13) |
264 				(((unsigned int)vd.mantissa4 >> 3) & MASK(13));
265 	shipit:
266 		id.sign = vd.sign;
267 		lp = (int32_t *)(void *)&id;
268 		return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
269 #endif
270 
271 	case XDR_DECODE:
272 #ifdef IEEEFP
273 		i32p = (int32_t *)(void *)dp;
274 #if BYTE_ORDER == BIG_ENDIAN || \
275     (defined(__arm__) && !defined(__VFP_FP__))
276 		rv = XDR_GETINT32(xdrs, i32p);
277 		if (!rv)
278 			return (rv);
279 		rv = XDR_GETINT32(xdrs, i32p+1);
280 #else
281 		rv = XDR_GETINT32(xdrs, i32p+1);
282 		if (!rv)
283 			return (rv);
284 		rv = XDR_GETINT32(xdrs, i32p);
285 #endif
286 		return (rv);
287 #else
288 		lp = (int32_t *)(void *)&id;
289 		if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
290 			return (FALSE);
291 		for (i = 0, lim = dbl_limits;
292 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
293 			i++, lim++) {
294 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
295 				(id.mantissa1 == lim->ieee.mantissa1) &&
296 				(id.exp == lim->ieee.exp)) {
297 				vd = lim->d;
298 				goto doneit;
299 			}
300 		}
301 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
302 		vd.mantissa1 = ((unsigned int)id.mantissa1 >> 13);
303 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
304 				((unsigned int)id.mantissa2 >> 29);
305 		vd.mantissa3 = ((unsigned int)id.mantissa2 >> 13);
306 		vd.mantissa4 = (id.mantissa2 << 3);
307 	doneit:
308 		vd.sign = id.sign;
309 		*dp = *((double *)(void *)&vd);
310 		return (TRUE);
311 #endif
312 
313 	case XDR_FREE:
314 		return (TRUE);
315 	}
316 	/* NOTREACHED */
317 	return (FALSE);
318 }
319