1 /*        $NetBSD: xdr_float.c,v 1.42 2024/04/11 18:41:03 christos 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 1.42 2024/04/11 18:41:03 christos 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 #include <string.h>
61 
62 #include <rpc/types.h>
63 #include <rpc/xdr.h>
64 
65 #ifdef __weak_alias
66 __weak_alias(xdr_double,_xdr_double)
67 __weak_alias(xdr_float,_xdr_float)
68 #endif
69 
70 /*
71  * NB: Not portable.
72  * This routine works on machines with IEEE754 FP and Vaxen.
73  */
74 
75 #if !defined(__vax__)
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
xdr_float(XDR * xdrs,float * fp)112 xdr_float(XDR *xdrs, float *fp)
113 {
114 #ifndef IEEEFP
115           struct ieee_single is;
116           struct vax_single vs, *vsp;
117           struct sgl_limits *lim;
118           size_t i;
119 #endif
120           switch (xdrs->x_op) {
121 
122           case XDR_ENCODE:
123 #ifdef IEEEFP
124                     return (XDR_PUTINT32(xdrs, (int32_t *)(void *)fp));
125 #else
126                     vs = *((struct vax_single *)(void *)fp);
127                     for (i = 0, lim = sgl_limits;
128                               i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
129                               i++, lim++) {
130                               if ((vs.mantissa2 == lim->s.mantissa2) &&
131                                         (vs.exp == lim->s.exp) &&
132                                         (vs.mantissa1 == lim->s.mantissa1)) {
133                                         is = lim->ieee;
134                                         goto shipit;
135                               }
136                     }
137                     is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
138                     is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
139           shipit:
140                     is.sign = vs.sign;
141                     return (XDR_PUTINT32(xdrs, (int32_t *)(void *)&is));
142 #endif
143 
144           case XDR_DECODE:
145 #ifdef IEEEFP
146                     return (XDR_GETINT32(xdrs, (int32_t *)(void *)fp));
147 #else
148                     vsp = (struct vax_single *)(void *)fp;
149                     if (!XDR_GETINT32(xdrs, (int32_t *)(void *)&is))
150                               return (FALSE);
151                     for (i = 0, lim = sgl_limits;
152                               i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
153                               i++, lim++) {
154                               if ((is.exp == lim->ieee.exp) &&
155                                         (is.mantissa == lim->ieee.mantissa)) {
156                                         *vsp = lim->s;
157                                         goto doneit;
158                               }
159                     }
160                     vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
161                     vsp->mantissa2 = is.mantissa;
162                     vsp->mantissa1 = ((unsigned int)is.mantissa >> 16);
163           doneit:
164                     vsp->sign = is.sign;
165                     return (TRUE);
166 #endif
167 
168           case XDR_FREE:
169                     return (TRUE);
170           }
171           /* NOTREACHED */
172           return (FALSE);
173 }
174 
175 #if defined(__vax__)
176 /* What IEEE double precision floating point looks like on a Vax */
177 struct    ieee_double {
178           unsigned int        mantissa1 : 20;
179           unsigned int        exp       : 11;
180           unsigned int        sign      : 1;
181           unsigned int        mantissa2 : 32;
182 };
183 
184 /* Vax double precision floating point */
185 struct  vax_double {
186           unsigned int        mantissa1 : 7;
187           unsigned int        exp       : 8;
188           unsigned int        sign      : 1;
189           unsigned int        mantissa2 : 16;
190           unsigned int        mantissa3 : 16;
191           unsigned int        mantissa4 : 16;
192 };
193 
194 #define VAX_DBL_BIAS          0x81
195 #define IEEE_DBL_BIAS         0x3ff
196 #define MASK(nbits) ((1 << nbits) - 1)
197 
198 static struct dbl_limits {
199           struct    vax_double d;
200           struct    ieee_double ieee;
201 } dbl_limits[2] = {
202           {{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },     /* Max Vax */
203           { 0x0, 0x7ff, 0x0, 0x0 }},                        /* Max IEEE */
204           {{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},                 /* Min Vax */
205           { 0x0, 0x0, 0x0, 0x0 }}                                     /* Min IEEE */
206 };
207 
208 #endif /* vax */
209 
210 
211 bool_t
xdr_double(XDR * xdrs,double * dp)212 xdr_double(XDR *xdrs, double *dp)
213 {
214 #ifdef IEEEFP
215           int32_t *i32p;
216           bool_t rv;
217 #else
218           int32_t *lp;
219           struct    ieee_double id;
220           struct    vax_double vd;
221           struct dbl_limits *lim;
222           size_t i;
223 #endif
224 
225           switch (xdrs->x_op) {
226 
227           case XDR_ENCODE:
228 #ifdef IEEEFP
229                     i32p = (int32_t *)(void *)dp;
230 #if (BYTE_ORDER == BIG_ENDIAN) || \
231     (defined(__arm__) && !defined(__VFP_FP__))
232                     rv = XDR_PUTINT32(xdrs, i32p);
233                     if (!rv)
234                               return (rv);
235                     rv = XDR_PUTINT32(xdrs, i32p+1);
236 #else
237                     rv = XDR_PUTINT32(xdrs, i32p+1);
238                     if (!rv)
239                               return (rv);
240                     rv = XDR_PUTINT32(xdrs, i32p);
241 #endif
242                     return (rv);
243 #else
244                     vd = *((struct vax_double *)(void *)dp);
245                     for (i = 0, lim = dbl_limits;
246                               i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
247                               i++, lim++) {
248                               if ((vd.mantissa4 == lim->d.mantissa4) &&
249                                         (vd.mantissa3 == lim->d.mantissa3) &&
250                                         (vd.mantissa2 == lim->d.mantissa2) &&
251                                         (vd.mantissa1 == lim->d.mantissa1) &&
252                                         (vd.exp == lim->d.exp)) {
253                                         id = lim->ieee;
254                                         goto shipit;
255                               }
256                     }
257                     /*LINTED: possible overflow*/
258                     id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
259                     id.mantissa1 = (vd.mantissa1 << 13) |
260                                   ((unsigned int)vd.mantissa2 >> 3);
261                     id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
262                                         (vd.mantissa3 << 13) |
263                                         (((unsigned int)vd.mantissa4 >> 3) & MASK(13));
264           shipit:
265                     id.sign = vd.sign;
266                     lp = (int32_t *)(void *)&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 || \
274     (defined(__arm__) && !defined(__VFP_FP__))
275                     rv = XDR_GETINT32(xdrs, i32p);
276                     if (!rv)
277                               return (rv);
278                     rv = XDR_GETINT32(xdrs, i32p+1);
279 #else
280                     rv = XDR_GETINT32(xdrs, i32p+1);
281                     if (!rv)
282                               return (rv);
283                     rv = XDR_GETINT32(xdrs, i32p);
284 #endif
285                     return (rv);
286 #else
287                     lp = (int32_t *)(void *)&id;
288                     if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(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                     /*LINTED: can overflow */
301                     vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
302                     vd.mantissa1 = ((unsigned int)id.mantissa1 >> 13);
303                     vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
304                                         ((unsigned int)id.mantissa2 >> 29);
305                     vd.mantissa3 = ((unsigned int)id.mantissa2 >> 13);
306                     vd.mantissa4 = (id.mantissa2 << 3);
307           doneit:
308                     vd.sign = id.sign;
309                     memcpy(dp, &vd, sizeof(double));
310                     return (TRUE);
311 #endif
312 
313           case XDR_FREE:
314                     return (TRUE);
315           }
316           /* NOTREACHED */
317           return (FALSE);
318 }
319