xref: /dragonfly/lib/libc/xdr/xdr_float.c (revision 279dd846)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
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9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  *
29  * @(#)xdr_float.c 1.12 87/08/11 Copyr 1984 Sun Micro
30  * @(#)xdr_float.c	2.1 88/07/29 4.0 RPCSRC
31  * $NetBSD: xdr_float.c,v 1.23 2000/07/17 04:59:51 matt Exp $
32  * $FreeBSD: src/lib/libc/xdr/xdr_float.c,v 1.14 2004/10/16 06:32:43 obrien Exp $
33  */
34 
35 /*
36  * xdr_float.c, Generic XDR routines implementation.
37  *
38  * Copyright (C) 1984, Sun Microsystems, Inc.
39  *
40  * These are the "floating point" xdr routines used to (de)serialize
41  * most common data items.  See xdr.h for more info on the interface to
42  * xdr.
43  */
44 
45 #include "namespace.h"
46 #include <sys/types.h>
47 #include <sys/param.h>
48 
49 #include <stdio.h>
50 
51 #include <rpc/types.h>
52 #include <rpc/xdr.h>
53 #include "un-namespace.h"
54 
55 /*
56  * NB: Not portable.
57  * This routine works on machines with IEEE754 FP and Vaxen.
58  */
59 
60 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
61     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
62     defined(__arm__) || defined(__ppc__) || defined(__ia64__) || \
63     defined(__arm26__) || defined(__sparc64__) || defined(__x86_64__)
64 #include <machine/endian.h>
65 #define IEEEFP
66 #endif
67 
68 #if defined(__vax__)
69 
70 /* What IEEE single precision floating point looks like on a Vax */
71 struct	ieee_single {
72 	unsigned int	mantissa: 23;
73 	unsigned int	exp     : 8;
74 	unsigned int	sign    : 1;
75 };
76 
77 /* Vax single precision floating point */
78 struct	vax_single {
79 	unsigned int	mantissa1 : 7;
80 	unsigned int	exp       : 8;
81 	unsigned int	sign      : 1;
82 	unsigned int	mantissa2 : 16;
83 };
84 
85 #define VAX_SNG_BIAS	0x81
86 #define IEEE_SNG_BIAS	0x7f
87 
88 static struct sgl_limits {
89 	struct vax_single s;
90 	struct ieee_single ieee;
91 } sgl_limits[2] = {
92 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
93 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
94 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
95 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
96 };
97 #endif /* vax */
98 
99 bool_t
100 xdr_float(XDR *xdrs, float *fp)
101 {
102 #ifndef IEEEFP
103 	struct ieee_single is;
104 	struct vax_single vs, *vsp;
105 	struct sgl_limits *lim;
106 	int i;
107 #endif
108 	switch (xdrs->x_op) {
109 
110 	case XDR_ENCODE:
111 #ifdef IEEEFP
112 		return (XDR_PUTINT32(xdrs, (int32_t *)fp));
113 #else
114 		vs = *((struct vax_single *)fp);
115 		for (i = 0, lim = sgl_limits;
116 			i < NELEM(sgl_limits);
117 			i++, lim++) {
118 			if ((vs.mantissa2 == lim->s.mantissa2) &&
119 				(vs.exp == lim->s.exp) &&
120 				(vs.mantissa1 == lim->s.mantissa1)) {
121 				is = lim->ieee;
122 				goto shipit;
123 			}
124 		}
125 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
126 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
127 	shipit:
128 		is.sign = vs.sign;
129 		return (XDR_PUTINT32(xdrs, (int32_t *)&is));
130 #endif
131 
132 	case XDR_DECODE:
133 #ifdef IEEEFP
134 		return (XDR_GETINT32(xdrs, (int32_t *)fp));
135 #else
136 		vsp = (struct vax_single *)fp;
137 		if (!XDR_GETINT32(xdrs, (int32_t *)&is))
138 			return (FALSE);
139 		for (i = 0, lim = sgl_limits;
140 			i < NELEM(sgl_limits);
141 			i++, lim++) {
142 			if ((is.exp == lim->ieee.exp) &&
143 				(is.mantissa == lim->ieee.mantissa)) {
144 				*vsp = lim->s;
145 				goto doneit;
146 			}
147 		}
148 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
149 		vsp->mantissa2 = is.mantissa;
150 		vsp->mantissa1 = (is.mantissa >> 16);
151 	doneit:
152 		vsp->sign = is.sign;
153 		return (TRUE);
154 #endif
155 
156 	case XDR_FREE:
157 		return (TRUE);
158 	}
159 	/* NOTREACHED */
160 	return (FALSE);
161 }
162 
163 #if defined(__vax__)
164 /* What IEEE double precision floating point looks like on a Vax */
165 struct	ieee_double {
166 	unsigned int	mantissa1 : 20;
167 	unsigned int	exp       : 11;
168 	unsigned int	sign      : 1;
169 	unsigned int	mantissa2 : 32;
170 };
171 
172 /* Vax double precision floating point */
173 struct  vax_double {
174 	unsigned int	mantissa1 : 7;
175 	unsigned int	exp       : 8;
176 	unsigned int	sign      : 1;
177 	unsigned int	mantissa2 : 16;
178 	unsigned int	mantissa3 : 16;
179 	unsigned int	mantissa4 : 16;
180 };
181 
182 #define VAX_DBL_BIAS	0x81
183 #define IEEE_DBL_BIAS	0x3ff
184 #define MASK(nbits)	((1 << nbits) - 1)
185 
186 static struct dbl_limits {
187 	struct	vax_double d;
188 	struct	ieee_double ieee;
189 } dbl_limits[2] = {
190 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
191 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
192 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
193 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
194 };
195 
196 #endif /* vax */
197 
198 
199 bool_t
200 xdr_double(XDR *xdrs, double *dp)
201 {
202 #ifdef IEEEFP
203 	int32_t *i32p;
204 	bool_t rv;
205 #else
206 	int32_t *lp;
207 	struct	ieee_double id;
208 	struct	vax_double vd;
209 	struct dbl_limits *lim;
210 	int i;
211 #endif
212 
213 	switch (xdrs->x_op) {
214 
215 	case XDR_ENCODE:
216 #ifdef IEEEFP
217 		i32p = (int32_t *)(void *)dp;
218 #if BYTE_ORDER == BIG_ENDIAN
219 		rv = XDR_PUTINT32(xdrs, i32p);
220 		if (!rv)
221 			return (rv);
222 		rv = XDR_PUTINT32(xdrs, i32p+1);
223 #else
224 		rv = XDR_PUTINT32(xdrs, i32p+1);
225 		if (!rv)
226 			return (rv);
227 		rv = XDR_PUTINT32(xdrs, i32p);
228 #endif
229 		return (rv);
230 #else
231 		vd = *((struct vax_double *)dp);
232 		for (i = 0, lim = dbl_limits;
233 			i < NELEM(dbl_limits);
234 			i++, lim++) {
235 			if ((vd.mantissa4 == lim->d.mantissa4) &&
236 				(vd.mantissa3 == lim->d.mantissa3) &&
237 				(vd.mantissa2 == lim->d.mantissa2) &&
238 				(vd.mantissa1 == lim->d.mantissa1) &&
239 				(vd.exp == lim->d.exp)) {
240 				id = lim->ieee;
241 				goto shipit;
242 			}
243 		}
244 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
245 		id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
246 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
247 				(vd.mantissa3 << 13) |
248 				((vd.mantissa4 >> 3) & MASK(13));
249 	shipit:
250 		id.sign = vd.sign;
251 		lp = (int32_t *)&id;
252 		return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
253 #endif
254 
255 	case XDR_DECODE:
256 #ifdef IEEEFP
257 		i32p = (int32_t *)(void *)dp;
258 #if BYTE_ORDER == BIG_ENDIAN
259 		rv = XDR_GETINT32(xdrs, i32p);
260 		if (!rv)
261 			return (rv);
262 		rv = XDR_GETINT32(xdrs, i32p+1);
263 #else
264 		rv = XDR_GETINT32(xdrs, i32p+1);
265 		if (!rv)
266 			return (rv);
267 		rv = XDR_GETINT32(xdrs, i32p);
268 #endif
269 		return (rv);
270 #else
271 		lp = (int32_t *)&id;
272 		if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
273 			return (FALSE);
274 		for (i = 0, lim = dbl_limits;
275 			i < NELEM(dbl_limits);
276 			i++, lim++) {
277 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
278 				(id.mantissa1 == lim->ieee.mantissa1) &&
279 				(id.exp == lim->ieee.exp)) {
280 				vd = lim->d;
281 				goto doneit;
282 			}
283 		}
284 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
285 		vd.mantissa1 = (id.mantissa1 >> 13);
286 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
287 				(id.mantissa2 >> 29);
288 		vd.mantissa3 = (id.mantissa2 >> 13);
289 		vd.mantissa4 = (id.mantissa2 << 3);
290 	doneit:
291 		vd.sign = id.sign;
292 		*dp = *((double *)&vd);
293 		return (TRUE);
294 #endif
295 
296 	case XDR_FREE:
297 		return (TRUE);
298 	}
299 	/* NOTREACHED */
300 	return (FALSE);
301 }
302