xref: /netbsd-src/lib/libc/rpc/xdr_float.c (revision f14316bcbc544b96a93e884bc5c2b15fd60e22ae)
1 /*	$NetBSD: xdr_float.c,v 1.39 2014/08/10 05:57:31 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 #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 1.39 2014/08/10 05:57:31 matt 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     defined(__aarch64__)
79 #include <machine/endian.h>
80 #define IEEEFP
81 #endif
82 
83 #if defined(__vax__)
84 
85 /* What IEEE single precision floating point looks like on a Vax */
86 struct	ieee_single {
87 	unsigned int	mantissa: 23;
88 	unsigned int	exp     : 8;
89 	unsigned int	sign    : 1;
90 };
91 
92 /* Vax single precision floating point */
93 struct	vax_single {
94 	unsigned int	mantissa1 : 7;
95 	unsigned int	exp       : 8;
96 	unsigned int	sign      : 1;
97 	unsigned int	mantissa2 : 16;
98 };
99 
100 #define VAX_SNG_BIAS	0x81
101 #define IEEE_SNG_BIAS	0x7f
102 
103 static struct sgl_limits {
104 	struct vax_single s;
105 	struct ieee_single ieee;
106 } sgl_limits[2] = {
107 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
108 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
109 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
110 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
111 };
112 #endif /* vax */
113 
114 bool_t
115 xdr_float(XDR *xdrs, float *fp)
116 {
117 #ifndef IEEEFP
118 	struct ieee_single is;
119 	struct vax_single vs, *vsp;
120 	struct sgl_limits *lim;
121 	size_t i;
122 #endif
123 	switch (xdrs->x_op) {
124 
125 	case XDR_ENCODE:
126 #ifdef IEEEFP
127 		return (XDR_PUTINT32(xdrs, (int32_t *)(void *)fp));
128 #else
129 		vs = *((struct vax_single *)(void *)fp);
130 		for (i = 0, lim = sgl_limits;
131 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
132 			i++, lim++) {
133 			if ((vs.mantissa2 == lim->s.mantissa2) &&
134 				(vs.exp == lim->s.exp) &&
135 				(vs.mantissa1 == lim->s.mantissa1)) {
136 				is = lim->ieee;
137 				goto shipit;
138 			}
139 		}
140 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
141 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
142 	shipit:
143 		is.sign = vs.sign;
144 		return (XDR_PUTINT32(xdrs, (int32_t *)(void *)&is));
145 #endif
146 
147 	case XDR_DECODE:
148 #ifdef IEEEFP
149 		return (XDR_GETINT32(xdrs, (int32_t *)(void *)fp));
150 #else
151 		vsp = (struct vax_single *)(void *)fp;
152 		if (!XDR_GETINT32(xdrs, (int32_t *)(void *)&is))
153 			return (FALSE);
154 		for (i = 0, lim = sgl_limits;
155 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
156 			i++, lim++) {
157 			if ((is.exp == lim->ieee.exp) &&
158 				(is.mantissa == lim->ieee.mantissa)) {
159 				*vsp = lim->s;
160 				goto doneit;
161 			}
162 		}
163 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
164 		vsp->mantissa2 = is.mantissa;
165 		vsp->mantissa1 = ((unsigned int)is.mantissa >> 16);
166 	doneit:
167 		vsp->sign = is.sign;
168 		return (TRUE);
169 #endif
170 
171 	case XDR_FREE:
172 		return (TRUE);
173 	}
174 	/* NOTREACHED */
175 	return (FALSE);
176 }
177 
178 #if defined(__vax__)
179 /* What IEEE double precision floating point looks like on a Vax */
180 struct	ieee_double {
181 	unsigned int	mantissa1 : 20;
182 	unsigned int	exp       : 11;
183 	unsigned int	sign      : 1;
184 	unsigned int	mantissa2 : 32;
185 };
186 
187 /* Vax double precision floating point */
188 struct  vax_double {
189 	unsigned int	mantissa1 : 7;
190 	unsigned int	exp       : 8;
191 	unsigned int	sign      : 1;
192 	unsigned int	mantissa2 : 16;
193 	unsigned int	mantissa3 : 16;
194 	unsigned int	mantissa4 : 16;
195 };
196 
197 #define VAX_DBL_BIAS	0x81
198 #define IEEE_DBL_BIAS	0x3ff
199 #define MASK(nbits)	((1 << nbits) - 1)
200 
201 static struct dbl_limits {
202 	struct	vax_double d;
203 	struct	ieee_double ieee;
204 } dbl_limits[2] = {
205 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
206 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
207 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
208 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
209 };
210 
211 #endif /* vax */
212 
213 
214 bool_t
215 xdr_double(XDR *xdrs, double *dp)
216 {
217 #ifdef IEEEFP
218 	int32_t *i32p;
219 	bool_t rv;
220 #else
221 	int32_t *lp;
222 	struct	ieee_double id;
223 	struct	vax_double vd;
224 	struct dbl_limits *lim;
225 	size_t i;
226 #endif
227 
228 	switch (xdrs->x_op) {
229 
230 	case XDR_ENCODE:
231 #ifdef IEEEFP
232 		i32p = (int32_t *)(void *)dp;
233 #if (BYTE_ORDER == BIG_ENDIAN) || \
234     (defined(__arm__) && !defined(__VFP_FP__))
235 		rv = XDR_PUTINT32(xdrs, i32p);
236 		if (!rv)
237 			return (rv);
238 		rv = XDR_PUTINT32(xdrs, i32p+1);
239 #else
240 		rv = XDR_PUTINT32(xdrs, i32p+1);
241 		if (!rv)
242 			return (rv);
243 		rv = XDR_PUTINT32(xdrs, i32p);
244 #endif
245 		return (rv);
246 #else
247 		vd = *((struct vax_double *)(void *)dp);
248 		for (i = 0, lim = dbl_limits;
249 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
250 			i++, lim++) {
251 			if ((vd.mantissa4 == lim->d.mantissa4) &&
252 				(vd.mantissa3 == lim->d.mantissa3) &&
253 				(vd.mantissa2 == lim->d.mantissa2) &&
254 				(vd.mantissa1 == lim->d.mantissa1) &&
255 				(vd.exp == lim->d.exp)) {
256 				id = lim->ieee;
257 				goto shipit;
258 			}
259 		}
260 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
261 		id.mantissa1 = (vd.mantissa1 << 13) |
262 			    ((unsigned int)vd.mantissa2 >> 3);
263 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
264 				(vd.mantissa3 << 13) |
265 				(((unsigned int)vd.mantissa4 >> 3) & MASK(13));
266 	shipit:
267 		id.sign = vd.sign;
268 		lp = (int32_t *)(void *)&id;
269 		return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
270 #endif
271 
272 	case XDR_DECODE:
273 #ifdef IEEEFP
274 		i32p = (int32_t *)(void *)dp;
275 #if BYTE_ORDER == BIG_ENDIAN || \
276     (defined(__arm__) && !defined(__VFP_FP__))
277 		rv = XDR_GETINT32(xdrs, i32p);
278 		if (!rv)
279 			return (rv);
280 		rv = XDR_GETINT32(xdrs, i32p+1);
281 #else
282 		rv = XDR_GETINT32(xdrs, i32p+1);
283 		if (!rv)
284 			return (rv);
285 		rv = XDR_GETINT32(xdrs, i32p);
286 #endif
287 		return (rv);
288 #else
289 		lp = (int32_t *)(void *)&id;
290 		if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
291 			return (FALSE);
292 		for (i = 0, lim = dbl_limits;
293 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
294 			i++, lim++) {
295 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
296 				(id.mantissa1 == lim->ieee.mantissa1) &&
297 				(id.exp == lim->ieee.exp)) {
298 				vd = lim->d;
299 				goto doneit;
300 			}
301 		}
302 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
303 		vd.mantissa1 = ((unsigned int)id.mantissa1 >> 13);
304 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
305 				((unsigned int)id.mantissa2 >> 29);
306 		vd.mantissa3 = ((unsigned int)id.mantissa2 >> 13);
307 		vd.mantissa4 = (id.mantissa2 << 3);
308 	doneit:
309 		vd.sign = id.sign;
310 		*dp = *((double *)(void *)&vd);
311 		return (TRUE);
312 #endif
313 
314 	case XDR_FREE:
315 		return (TRUE);
316 	}
317 	/* NOTREACHED */
318 	return (FALSE);
319 }
320