xref: /netbsd-src/lib/libc/rpc/xdr_float.c (revision d83d59241ece2a1b3aa57270eda86283beef6f19)
1 /*	$NetBSD: xdr_float.c,v 1.11 1997/03/29 21:04:08 thorpej 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 #if defined(LIBC_SCCS) && !defined(lint)
33 /*static char *sccsid = "from: @(#)xdr_float.c 1.12 87/08/11 Copyr 1984 Sun Micro";*/
34 /*static char *sccsid = "from: @(#)xdr_float.c	2.1 88/07/29 4.0 RPCSRC";*/
35 static char *rcsid = "$NetBSD: xdr_float.c,v 1.11 1997/03/29 21:04:08 thorpej Exp $";
36 #endif
37 
38 /*
39  * xdr_float.c, Generic XDR routines impelmentation.
40  *
41  * Copyright (C) 1984, Sun Microsystems, Inc.
42  *
43  * These are the "floating point" xdr routines used to (de)serialize
44  * most common data items.  See xdr.h for more info on the interface to
45  * xdr.
46  */
47 
48 #include <stdio.h>
49 #include <sys/types.h>
50 #include <sys/param.h>
51 #include <rpc/types.h>
52 #include <rpc/xdr.h>
53 
54 /*
55  * NB: Not portable.
56  * This routine works on machines with IEEE754 FP and Vaxen.
57  */
58 
59 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
60     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
61     defined(__arm32__) || defined(__powerpc__)
62 #include <machine/endian.h>
63 #define IEEEFP
64 #endif
65 
66 #ifdef vax
67 
68 /* What IEEE single precision floating point looks like on a Vax */
69 struct	ieee_single {
70 	unsigned int	mantissa: 23;
71 	unsigned int	exp     : 8;
72 	unsigned int	sign    : 1;
73 };
74 
75 /* Vax single precision floating point */
76 struct	vax_single {
77 	unsigned int	mantissa1 : 7;
78 	unsigned int	exp       : 8;
79 	unsigned int	sign      : 1;
80 	unsigned int	mantissa2 : 16;
81 };
82 
83 #define VAX_SNG_BIAS	0x81
84 #define IEEE_SNG_BIAS	0x7f
85 
86 static struct sgl_limits {
87 	struct vax_single s;
88 	struct ieee_single ieee;
89 } sgl_limits[2] = {
90 	{{ 0x7f, 0xff, 0x0, 0xffff },	/* Max Vax */
91 	{ 0x0, 0xff, 0x0 }},		/* Max IEEE */
92 	{{ 0x0, 0x0, 0x0, 0x0 },	/* Min Vax */
93 	{ 0x0, 0x0, 0x0 }}		/* Min IEEE */
94 };
95 #endif /* vax */
96 
97 bool_t
98 xdr_float(xdrs, fp)
99 	register XDR *xdrs;
100 	register float *fp;
101 {
102 #ifdef IEEEFP
103 	bool_t rv;
104 	long tmpl;
105 #else
106 	struct ieee_single is;
107 	struct vax_single vs, *vsp;
108 	struct sgl_limits *lim;
109 	int i;
110 #endif
111 	switch (xdrs->x_op) {
112 
113 	case XDR_ENCODE:
114 #ifdef IEEEFP
115 		tmpl = *(int32_t *)fp;
116 		return (XDR_PUTLONG(xdrs, &tmpl));
117 #else
118 		vs = *((struct vax_single *)fp);
119 		for (i = 0, lim = sgl_limits;
120 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
121 			i++, lim++) {
122 			if ((vs.mantissa2 == lim->s.mantissa2) &&
123 				(vs.exp == lim->s.exp) &&
124 				(vs.mantissa1 == lim->s.mantissa1)) {
125 				is = lim->ieee;
126 				goto shipit;
127 			}
128 		}
129 		is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
130 		is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
131 	shipit:
132 		is.sign = vs.sign;
133 		return (XDR_PUTLONG(xdrs, (long *)&is));
134 #endif
135 
136 	case XDR_DECODE:
137 #ifdef IEEEFP
138 		rv = XDR_GETLONG(xdrs, &tmpl);
139 		*(int32_t *)fp = tmpl;
140 		return (rv);
141 #else
142 		vsp = (struct vax_single *)fp;
143 		if (!XDR_GETLONG(xdrs, (long *)&is))
144 			return (FALSE);
145 		for (i = 0, lim = sgl_limits;
146 			i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
147 			i++, lim++) {
148 			if ((is.exp == lim->ieee.exp) &&
149 				(is.mantissa == lim->ieee.mantissa)) {
150 				*vsp = lim->s;
151 				goto doneit;
152 			}
153 		}
154 		vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
155 		vsp->mantissa2 = is.mantissa;
156 		vsp->mantissa1 = (is.mantissa >> 16);
157 	doneit:
158 		vsp->sign = is.sign;
159 		return (TRUE);
160 #endif
161 
162 	case XDR_FREE:
163 		return (TRUE);
164 	}
165 	return (FALSE);
166 }
167 
168 #ifdef vax
169 /* What IEEE double precision floating point looks like on a Vax */
170 struct	ieee_double {
171 	unsigned int	mantissa1 : 20;
172 	unsigned int	exp       : 11;
173 	unsigned int	sign      : 1;
174 	unsigned int	mantissa2 : 32;
175 };
176 
177 /* Vax double precision floating point */
178 struct  vax_double {
179 	unsigned int	mantissa1 : 7;
180 	unsigned int	exp       : 8;
181 	unsigned int	sign      : 1;
182 	unsigned int	mantissa2 : 16;
183 	unsigned int	mantissa3 : 16;
184 	unsigned int	mantissa4 : 16;
185 };
186 
187 #define VAX_DBL_BIAS	0x81
188 #define IEEE_DBL_BIAS	0x3ff
189 #define MASK(nbits)	((1 << nbits) - 1)
190 
191 static struct dbl_limits {
192 	struct	vax_double d;
193 	struct	ieee_double ieee;
194 } dbl_limits[2] = {
195 	{{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },	/* Max Vax */
196 	{ 0x0, 0x7ff, 0x0, 0x0 }},			/* Max IEEE */
197 	{{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},		/* Min Vax */
198 	{ 0x0, 0x0, 0x0, 0x0 }}				/* Min IEEE */
199 };
200 
201 #endif /* vax */
202 
203 
204 bool_t
205 xdr_double(xdrs, dp)
206 	register XDR *xdrs;
207 	double *dp;
208 {
209 #ifdef IEEEFP
210 	register int32_t *i32p;
211 	bool_t rv;
212 	long tmpl;
213 #else
214 	register long *lp;
215 	struct	ieee_double id;
216 	struct	vax_double vd;
217 	register struct dbl_limits *lim;
218 	int i;
219 #endif
220 
221 	switch (xdrs->x_op) {
222 
223 	case XDR_ENCODE:
224 #ifdef IEEEFP
225 		i32p = (int32_t *)dp;
226 #if BYTE_ORDER == BIG_ENDIAN
227 		tmpl = *i32p++;
228 		rv = XDR_PUTLONG(xdrs, &tmpl);
229 		if (!rv)
230 			return (rv);
231 		tmpl = *i32p;
232 		rv = XDR_PUTLONG(xdrs, &tmpl);
233 #else
234 		tmpl = *(i32p+1);
235 		rv = XDR_PUTLONG(xdrs, &tmpl);
236 		if (!rv)
237 			return (rv);
238 		tmpl = *i32p;
239 		rv = XDR_PUTLONG(xdrs, &tmpl);
240 #endif
241 		return (rv);
242 #else
243 		vd = *((struct vax_double *)dp);
244 		for (i = 0, lim = dbl_limits;
245 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
246 			i++, lim++) {
247 			if ((vd.mantissa4 == lim->d.mantissa4) &&
248 				(vd.mantissa3 == lim->d.mantissa3) &&
249 				(vd.mantissa2 == lim->d.mantissa2) &&
250 				(vd.mantissa1 == lim->d.mantissa1) &&
251 				(vd.exp == lim->d.exp)) {
252 				id = lim->ieee;
253 				goto shipit;
254 			}
255 		}
256 		id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
257 		id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
258 		id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
259 				(vd.mantissa3 << 13) |
260 				((vd.mantissa4 >> 3) & MASK(13));
261 	shipit:
262 		id.sign = vd.sign;
263 		lp = (long *)&id;
264 		return (XDR_PUTLONG(xdrs, lp++) && XDR_PUTLONG(xdrs, lp));
265 #endif
266 
267 	case XDR_DECODE:
268 #ifdef IEEEFP
269 		i32p = (int32_t *)dp;
270 #if BYTE_ORDER == BIG_ENDIAN
271 		rv = XDR_GETLONG(xdrs, &tmpl);
272 		*i32p++ = tmpl;
273 		if (!rv)
274 			return (rv);
275 		rv = XDR_GETLONG(xdrs, &tmpl);
276 		*i32p = tmpl;
277 #else
278 		rv = XDR_GETLONG(xdrs, &tmpl);
279 		*(i32p+1) = tmpl;
280 		if (!rv)
281 			return (rv);
282 		rv = XDR_GETLONG(xdrs, &tmpl);
283 		*i32p = tmpl;
284 #endif
285 		return (rv);
286 #else
287 		lp = (long *)&id;
288 		if (!XDR_GETLONG(xdrs, lp++) || !XDR_GETLONG(xdrs, lp))
289 			return (FALSE);
290 		for (i = 0, lim = dbl_limits;
291 			i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
292 			i++, lim++) {
293 			if ((id.mantissa2 == lim->ieee.mantissa2) &&
294 				(id.mantissa1 == lim->ieee.mantissa1) &&
295 				(id.exp == lim->ieee.exp)) {
296 				vd = lim->d;
297 				goto doneit;
298 			}
299 		}
300 		vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
301 		vd.mantissa1 = (id.mantissa1 >> 13);
302 		vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
303 				(id.mantissa2 >> 29);
304 		vd.mantissa3 = (id.mantissa2 >> 13);
305 		vd.mantissa4 = (id.mantissa2 << 3);
306 	doneit:
307 		vd.sign = id.sign;
308 		*dp = *((double *)&vd);
309 		return (TRUE);
310 #endif
311 
312 	case XDR_FREE:
313 		return (TRUE);
314 	}
315 	return (FALSE);
316 }
317