xref: /netbsd-src/lib/libc/rpc/xdr_float.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: xdr_float.c,v 1.21 2000/05/09 21:55:52 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 1.21 2000/05/09 21:55:52 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(__arm32__) || defined(__powerpc__) || defined(__sh3__) || \
75     defined(__arm26__)
76 #include <machine/endian.h>
77 #define IEEEFP
78 #endif
79 
80 #if defined(__vax__)
81 
82 /* What IEEE single precision floating point looks like on a Vax */
83 struct	ieee_single {
84 	unsigned int	mantissa: 23;
85 	unsigned int	exp     : 8;
86 	unsigned int	sign    : 1;
87 };
88 
89 /* Vax single precision floating point */
90 struct	vax_single {
91 	unsigned int	mantissa1 : 7;
92 	unsigned int	exp       : 8;
93 	unsigned int	sign      : 1;
94 	unsigned int	mantissa2 : 16;
95 };
96 
97 #define VAX_SNG_BIAS	0x81
98 #define IEEE_SNG_BIAS	0x7f
99 
100 static struct sgl_limits {
101 	struct vax_single s;
102 	struct ieee_single ieee;
103 } sgl_limits[2] = {
104 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
105 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
106 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
107 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
108 };
109 #endif /* vax */
110 
111 bool_t
112 xdr_float(xdrs, fp)
113 	XDR *xdrs;
114 	float *fp;
115 {
116 #ifdef IEEEFP
117 	bool_t rv;
118 	long tmpl;
119 #else
120 	struct ieee_single is;
121 	struct vax_single vs, *vsp;
122 	struct sgl_limits *lim;
123 	int i;
124 #endif
125 	switch (xdrs->x_op) {
126 
127 	case XDR_ENCODE:
128 #ifdef IEEEFP
129 		tmpl = *(int32_t *)(void *)fp;
130 		return (XDR_PUTLONG(xdrs, &tmpl));
131 #else
132 		vs = *((struct vax_single *)fp);
133 		for (i = 0, lim = sgl_limits;
134 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
135 			i++, lim++) {
136 			if ((vs.mantissa2 == lim->s.mantissa2) &&
137 				(vs.exp == lim->s.exp) &&
138 				(vs.mantissa1 == lim->s.mantissa1)) {
139 				is = lim->ieee;
140 				goto shipit;
141 			}
142 		}
143 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
144 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
145 	shipit:
146 		is.sign = vs.sign;
147 		return (XDR_PUTLONG(xdrs, (long *)&is));
148 #endif
149 
150 	case XDR_DECODE:
151 #ifdef IEEEFP
152 		rv = XDR_GETLONG(xdrs, &tmpl);
153 		*(int32_t *)(void *)fp = (int32_t)tmpl;
154 		return (rv);
155 #else
156 		vsp = (struct vax_single *)fp;
157 		if (!XDR_GETLONG(xdrs, (long *)&is))
158 			return (FALSE);
159 		for (i = 0, lim = sgl_limits;
160 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
161 			i++, lim++) {
162 			if ((is.exp == lim->ieee.exp) &&
163 				(is.mantissa == lim->ieee.mantissa)) {
164 				*vsp = lim->s;
165 				goto doneit;
166 			}
167 		}
168 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
169 		vsp->mantissa2 = is.mantissa;
170 		vsp->mantissa1 = (is.mantissa >> 16);
171 	doneit:
172 		vsp->sign = is.sign;
173 		return (TRUE);
174 #endif
175 
176 	case XDR_FREE:
177 		return (TRUE);
178 	}
179 	/* NOTREACHED */
180 	return (FALSE);
181 }
182 
183 #if defined(__vax__)
184 /* What IEEE double precision floating point looks like on a Vax */
185 struct	ieee_double {
186 	unsigned int	mantissa1 : 20;
187 	unsigned int	exp       : 11;
188 	unsigned int	sign      : 1;
189 	unsigned int	mantissa2 : 32;
190 };
191 
192 /* Vax double precision floating point */
193 struct  vax_double {
194 	unsigned int	mantissa1 : 7;
195 	unsigned int	exp       : 8;
196 	unsigned int	sign      : 1;
197 	unsigned int	mantissa2 : 16;
198 	unsigned int	mantissa3 : 16;
199 	unsigned int	mantissa4 : 16;
200 };
201 
202 #define VAX_DBL_BIAS	0x81
203 #define IEEE_DBL_BIAS	0x3ff
204 #define MASK(nbits)	((1 << nbits) - 1)
205 
206 static struct dbl_limits {
207 	struct	vax_double d;
208 	struct	ieee_double ieee;
209 } dbl_limits[2] = {
210 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
211 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
212 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
213 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
214 };
215 
216 #endif /* vax */
217 
218 
219 bool_t
220 xdr_double(xdrs, dp)
221 	XDR *xdrs;
222 	double *dp;
223 {
224 #ifdef IEEEFP
225 	int32_t *i32p;
226 	bool_t rv;
227 	long tmpl;
228 #else
229 	long *lp;
230 	struct	ieee_double id;
231 	struct	vax_double vd;
232 	struct dbl_limits *lim;
233 	int i;
234 #endif
235 
236 	switch (xdrs->x_op) {
237 
238 	case XDR_ENCODE:
239 #ifdef IEEEFP
240 		i32p = (int32_t *)(void *)dp;
241 #if BYTE_ORDER == BIG_ENDIAN
242 		tmpl = *i32p++;
243 		rv = XDR_PUTLONG(xdrs, &tmpl);
244 		if (!rv)
245 			return (rv);
246 		tmpl = *i32p;
247 		rv = XDR_PUTLONG(xdrs, &tmpl);
248 #else
249 		tmpl = *(i32p+1);
250 		rv = XDR_PUTLONG(xdrs, &tmpl);
251 		if (!rv)
252 			return (rv);
253 		tmpl = *i32p;
254 		rv = XDR_PUTLONG(xdrs, &tmpl);
255 #endif
256 		return (rv);
257 #else
258 		vd = *((struct vax_double *)dp);
259 		for (i = 0, lim = dbl_limits;
260 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
261 			i++, lim++) {
262 			if ((vd.mantissa4 == lim->d.mantissa4) &&
263 				(vd.mantissa3 == lim->d.mantissa3) &&
264 				(vd.mantissa2 == lim->d.mantissa2) &&
265 				(vd.mantissa1 == lim->d.mantissa1) &&
266 				(vd.exp == lim->d.exp)) {
267 				id = lim->ieee;
268 				goto shipit;
269 			}
270 		}
271 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
272 		id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
273 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
274 				(vd.mantissa3 << 13) |
275 				((vd.mantissa4 >> 3) & MASK(13));
276 	shipit:
277 		id.sign = vd.sign;
278 		lp = (long *)&id;
279 		return (XDR_PUTLONG(xdrs, lp++) && XDR_PUTLONG(xdrs, lp));
280 #endif
281 
282 	case XDR_DECODE:
283 #ifdef IEEEFP
284 		i32p = (int32_t *)(void *)dp;
285 #if BYTE_ORDER == BIG_ENDIAN
286 		rv = XDR_GETLONG(xdrs, &tmpl);
287 		*i32p++ = tmpl;
288 		if (!rv)
289 			return (rv);
290 		rv = XDR_GETLONG(xdrs, &tmpl);
291 		*i32p = tmpl;
292 #else
293 		rv = XDR_GETLONG(xdrs, &tmpl);
294 		*(i32p+1) = (int32_t)tmpl;
295 		if (!rv)
296 			return (rv);
297 		rv = XDR_GETLONG(xdrs, &tmpl);
298 		*i32p = (int32_t)tmpl;
299 #endif
300 		return (rv);
301 #else
302 		lp = (long *)&id;
303 		if (!XDR_GETLONG(xdrs, lp++) || !XDR_GETLONG(xdrs, lp))
304 			return (FALSE);
305 		for (i = 0, lim = dbl_limits;
306 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
307 			i++, lim++) {
308 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
309 				(id.mantissa1 == lim->ieee.mantissa1) &&
310 				(id.exp == lim->ieee.exp)) {
311 				vd = lim->d;
312 				goto doneit;
313 			}
314 		}
315 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
316 		vd.mantissa1 = (id.mantissa1 >> 13);
317 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
318 				(id.mantissa2 >> 29);
319 		vd.mantissa3 = (id.mantissa2 >> 13);
320 		vd.mantissa4 = (id.mantissa2 << 3);
321 	doneit:
322 		vd.sign = id.sign;
323 		*dp = *((double *)&vd);
324 		return (TRUE);
325 #endif
326 
327 	case XDR_FREE:
328 		return (TRUE);
329 	}
330 	/* NOTREACHED */
331 	return (FALSE);
332 }
333