xref: /netbsd-src/lib/libc/rpc/xdr_float.c (revision 45531ab974cc9964d19fb2eb359c4afd39612917)
1 /*	$NetBSD: xdr_float.c,v 1.26 2001/02/18 22:13:41 bjh21 Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char *sccsid = "@(#)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 #else
38 __RCSID("$NetBSD: xdr_float.c,v 1.26 2001/02/18 22:13:41 bjh21 Exp $");
39 #endif
40 #endif
41 
42 /*
43  * xdr_float.c, Generic XDR routines impelmentation.
44  *
45  * Copyright (C) 1984, Sun Microsystems, Inc.
46  *
47  * These are the "floating point" xdr routines used to (de)serialize
48  * most common data items.  See xdr.h for more info on the interface to
49  * xdr.
50  */
51 
52 #include "namespace.h"
53 
54 #include <sys/types.h>
55 #include <sys/param.h>
56 
57 #include <stdio.h>
58 
59 #include <rpc/types.h>
60 #include <rpc/xdr.h>
61 
62 #ifdef __weak_alias
63 __weak_alias(xdr_double,_xdr_double)
64 __weak_alias(xdr_float,_xdr_float)
65 #endif
66 
67 /*
68  * NB: Not portable.
69  * This routine works on machines with IEEE754 FP and Vaxen.
70  */
71 
72 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
73     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
74     defined(__arm__) || defined(__powerpc__) || defined(__sh3__)
75 #include <machine/endian.h>
76 #define IEEEFP
77 #endif
78 
79 #if defined(__vax__)
80 
81 /* What IEEE single precision floating point looks like on a Vax */
82 struct	ieee_single {
83 	unsigned int	mantissa: 23;
84 	unsigned int	exp     : 8;
85 	unsigned int	sign    : 1;
86 };
87 
88 /* Vax single precision floating point */
89 struct	vax_single {
90 	unsigned int	mantissa1 : 7;
91 	unsigned int	exp       : 8;
92 	unsigned int	sign      : 1;
93 	unsigned int	mantissa2 : 16;
94 };
95 
96 #define VAX_SNG_BIAS	0x81
97 #define IEEE_SNG_BIAS	0x7f
98 
99 static struct sgl_limits {
100 	struct vax_single s;
101 	struct ieee_single ieee;
102 } sgl_limits[2] = {
103 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
104 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
105 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
106 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
107 };
108 #endif /* vax */
109 
110 bool_t
111 xdr_float(xdrs, fp)
112 	XDR *xdrs;
113 	float *fp;
114 {
115 #ifndef IEEEFP
116 	struct ieee_single is;
117 	struct vax_single vs, *vsp;
118 	struct sgl_limits *lim;
119 	int i;
120 #endif
121 	switch (xdrs->x_op) {
122 
123 	case XDR_ENCODE:
124 #ifdef IEEEFP
125 		return (XDR_PUTINT32(xdrs, (int32_t *)(void *)fp));
126 #else
127 		vs = *((struct vax_single *)fp);
128 		for (i = 0, lim = sgl_limits;
129 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
130 			i++, lim++) {
131 			if ((vs.mantissa2 == lim->s.mantissa2) &&
132 				(vs.exp == lim->s.exp) &&
133 				(vs.mantissa1 == lim->s.mantissa1)) {
134 				is = lim->ieee;
135 				goto shipit;
136 			}
137 		}
138 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
139 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
140 	shipit:
141 		is.sign = vs.sign;
142 		return (XDR_PUTINT32(xdrs, (int32_t *)&is));
143 #endif
144 
145 	case XDR_DECODE:
146 #ifdef IEEEFP
147 		return (XDR_GETINT32(xdrs, (int32_t *)(void *)fp));
148 #else
149 		vsp = (struct vax_single *)fp;
150 		if (!XDR_GETINT32(xdrs, (int32_t *)&is))
151 			return (FALSE);
152 		for (i = 0, lim = sgl_limits;
153 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
154 			i++, lim++) {
155 			if ((is.exp == lim->ieee.exp) &&
156 				(is.mantissa == lim->ieee.mantissa)) {
157 				*vsp = lim->s;
158 				goto doneit;
159 			}
160 		}
161 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
162 		vsp->mantissa2 = is.mantissa;
163 		vsp->mantissa1 = (is.mantissa >> 16);
164 	doneit:
165 		vsp->sign = is.sign;
166 		return (TRUE);
167 #endif
168 
169 	case XDR_FREE:
170 		return (TRUE);
171 	}
172 	/* NOTREACHED */
173 	return (FALSE);
174 }
175 
176 #if defined(__vax__)
177 /* What IEEE double precision floating point looks like on a Vax */
178 struct	ieee_double {
179 	unsigned int	mantissa1 : 20;
180 	unsigned int	exp       : 11;
181 	unsigned int	sign      : 1;
182 	unsigned int	mantissa2 : 32;
183 };
184 
185 /* Vax double precision floating point */
186 struct  vax_double {
187 	unsigned int	mantissa1 : 7;
188 	unsigned int	exp       : 8;
189 	unsigned int	sign      : 1;
190 	unsigned int	mantissa2 : 16;
191 	unsigned int	mantissa3 : 16;
192 	unsigned int	mantissa4 : 16;
193 };
194 
195 #define VAX_DBL_BIAS	0x81
196 #define IEEE_DBL_BIAS	0x3ff
197 #define MASK(nbits)	((1 << nbits) - 1)
198 
199 static struct dbl_limits {
200 	struct	vax_double d;
201 	struct	ieee_double ieee;
202 } dbl_limits[2] = {
203 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
204 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
205 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
206 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
207 };
208 
209 #endif /* vax */
210 
211 
212 bool_t
213 xdr_double(xdrs, dp)
214 	XDR *xdrs;
215 	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 	int 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) || defined(__arm__)
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 *)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) | (vd.mantissa2 >> 3);
261 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
262 				(vd.mantissa3 << 13) |
263 				((vd.mantissa4 >> 3) & MASK(13));
264 	shipit:
265 		id.sign = vd.sign;
266 		lp = (int32_t *)&id;
267 		return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
268 #endif
269 
270 	case XDR_DECODE:
271 #ifdef IEEEFP
272 		i32p = (int32_t *)(void *)dp;
273 #if BYTE_ORDER == BIG_ENDIAN || defined(__arm__)
274 		rv = XDR_GETINT32(xdrs, i32p);
275 		if (!rv)
276 			return (rv);
277 		rv = XDR_GETINT32(xdrs, i32p+1);
278 #else
279 		rv = XDR_GETINT32(xdrs, i32p+1);
280 		if (!rv)
281 			return (rv);
282 		rv = XDR_GETINT32(xdrs, i32p);
283 #endif
284 		return (rv);
285 #else
286 		lp = (int32_t *)&id;
287 		if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
288 			return (FALSE);
289 		for (i = 0, lim = dbl_limits;
290 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
291 			i++, lim++) {
292 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
293 				(id.mantissa1 == lim->ieee.mantissa1) &&
294 				(id.exp == lim->ieee.exp)) {
295 				vd = lim->d;
296 				goto doneit;
297 			}
298 		}
299 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
300 		vd.mantissa1 = (id.mantissa1 >> 13);
301 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
302 				(id.mantissa2 >> 29);
303 		vd.mantissa3 = (id.mantissa2 >> 13);
304 		vd.mantissa4 = (id.mantissa2 << 3);
305 	doneit:
306 		vd.sign = id.sign;
307 		*dp = *((double *)&vd);
308 		return (TRUE);
309 #endif
310 
311 	case XDR_FREE:
312 		return (TRUE);
313 	}
314 	/* NOTREACHED */
315 	return (FALSE);
316 }
317