lib/libc/xdr/xdr_float.c

   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.
   8  *
   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  * $DragonFly: src/lib/libc/xdr/xdr_float.c,v 1.6 2006/07/27 00:43:17 corecode Exp $
  34  */
  35
  36 /*
  37  * xdr_float.c, Generic XDR routines implementation.
  38  *
  39  * Copyright (C) 1984, Sun Microsystems, Inc.
  40  *
  41  * These are the "floating point" xdr routines used to (de)serialize
  42  * most common data items.  See xdr.h for more info on the interface to
  43  * xdr.
  44  */
  45
  46 #include "namespace.h"
  47 #include <sys/types.h>
  48 #include <sys/param.h>
  49
  50 #include <stdio.h>
  51
  52 #include <rpc/types.h>
  53 #include <rpc/xdr.h>
  54 #include "un-namespace.h"
  55
  56 /*
  57  * NB: Not portable.
  58  * This routine works on machines with IEEE754 FP and Vaxen.
  59  */
  60
  61 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
  62     defined(__mips__) || defined(__ns32k__) || defined(__alpha__) || \
  63     defined(__arm__) || defined(__ppc__) || defined(__ia64__) || \
  64     defined(__arm26__) || defined(__sparc64__) || defined(__amd64__)
  65 #include <machine/endian.h>
  66 #define IEEEFP
  67 #endif
  68
  69 #if defined(__vax__)
  70
  71 /* What IEEE single precision floating point looks like on a Vax */
  72 struct  ieee_single {
  73         unsigned int    mantissa: 23;
  74         unsigned int    exp     : 8;
  75         unsigned int    sign    : 1;
  76 };
  77
  78 /* Vax single precision floating point */
  79 struct  vax_single {
  80         unsigned int    mantissa1 : 7;
  81         unsigned int    exp       : 8;
  82         unsigned int    sign      : 1;
  83         unsigned int    mantissa2 : 16;
  84 };
  85
  86 #define VAX_SNG_BIAS    0x81
  87 #define IEEE_SNG_BIAS   0x7f
  88
  89 static struct sgl_limits {
  90         struct vax_single s;
  91         struct ieee_single ieee;
  92 } sgl_limits[2] = {
  93         {{ 0x7f, 0xff, 0x0, 0xffff },   /* Max Vax */
  94         { 0x0, 0xff, 0x0 }},            /* Max IEEE */
  95         {{ 0x0, 0x0, 0x0, 0x0 },        /* Min Vax */
  96         { 0x0, 0x0, 0x0 }}              /* Min IEEE */
  97 };
  98 #endif /* vax */
  99
 100 bool_t
 101 xdr_float(XDR *xdrs, float *fp)
 102 {
 103 #ifndef IEEEFP
 104         struct ieee_single is;
 105         struct vax_single vs, *vsp;
 106         struct sgl_limits *lim;
 107         int i;
 108 #endif
 109         switch (xdrs->x_op) {
 110
 111         case XDR_ENCODE:
 112 #ifdef IEEEFP
 113                 return (XDR_PUTINT32(xdrs, (int32_t *)fp));
 114 #else
 115                 vs = *((struct vax_single *)fp);
 116                 for (i = 0, lim = sgl_limits;
 117                         i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
 118                         i++, lim++) {
 119                         if ((vs.mantissa2 == lim->s.mantissa2) &&
 120                                 (vs.exp == lim->s.exp) &&
 121                                 (vs.mantissa1 == lim->s.mantissa1)) {
 122                                 is = lim->ieee;
 123                                 goto shipit;
 124                         }
 125                 }
 126                 is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
 127                 is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
 128         shipit:
 129                 is.sign = vs.sign;
 130                 return (XDR_PUTINT32(xdrs, (int32_t *)&is));
 131 #endif
 132
 133         case XDR_DECODE:
 134 #ifdef IEEEFP
 135                 return (XDR_GETINT32(xdrs, (int32_t *)fp));
 136 #else
 137                 vsp = (struct vax_single *)fp;
 138                 if (!XDR_GETINT32(xdrs, (int32_t *)&is))
 139                         return (FALSE);
 140                 for (i = 0, lim = sgl_limits;
 141                         i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
 142                         i++, lim++) {
 143                         if ((is.exp == lim->ieee.exp) &&
 144                                 (is.mantissa == lim->ieee.mantissa)) {
 145                                 *vsp = lim->s;
 146                                 goto doneit;
 147                         }
 148                 }
 149                 vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS;
 150                 vsp->mantissa2 = is.mantissa;
 151                 vsp->mantissa1 = (is.mantissa >> 16);
 152         doneit:
 153                 vsp->sign = is.sign;
 154                 return (TRUE);
 155 #endif
 156
 157         case XDR_FREE:
 158                 return (TRUE);
 159         }
 160         /* NOTREACHED */
 161         return (FALSE);
 162 }
 163
 164 #if defined(__vax__)
 165 /* What IEEE double precision floating point looks like on a Vax */
 166 struct  ieee_double {
 167         unsigned int    mantissa1 : 20;
 168         unsigned int    exp       : 11;
 169         unsigned int    sign      : 1;
 170         unsigned int    mantissa2 : 32;
 171 };
 172
 173 /* Vax double precision floating point */
 174 struct  vax_double {
 175         unsigned int    mantissa1 : 7;
 176         unsigned int    exp       : 8;
 177         unsigned int    sign      : 1;
 178         unsigned int    mantissa2 : 16;
 179         unsigned int    mantissa3 : 16;
 180         unsigned int    mantissa4 : 16;
 181 };
 182
 183 #define VAX_DBL_BIAS    0x81
 184 #define IEEE_DBL_BIAS   0x3ff
 185 #define MASK(nbits)     ((1 << nbits) - 1)
 186
 187 static struct dbl_limits {
 188         struct  vax_double d;
 189         struct  ieee_double ieee;
 190 } dbl_limits[2] = {
 191         {{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff },   /* Max Vax */
 192         { 0x0, 0x7ff, 0x0, 0x0 }},                      /* Max IEEE */
 193         {{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},               /* Min Vax */
 194         { 0x0, 0x0, 0x0, 0x0 }}                         /* Min IEEE */
 195 };
 196
 197 #endif /* vax */
 198
 199
 200 bool_t
 201 xdr_double(XDR *xdrs, double *dp)
 202 {
 203 #ifdef IEEEFP
 204         int32_t *i32p;
 205         bool_t rv;
 206 #else
 207         int32_t *lp;
 208         struct  ieee_double id;
 209         struct  vax_double vd;
 210         struct dbl_limits *lim;
 211         int i;
 212 #endif
 213
 214         switch (xdrs->x_op) {
 215
 216         case XDR_ENCODE:
 217 #ifdef IEEEFP
 218                 i32p = (int32_t *)(void *)dp;
 219 #if BYTE_ORDER == BIG_ENDIAN
 220                 rv = XDR_PUTINT32(xdrs, i32p);
 221                 if (!rv)
 222                         return (rv);
 223                 rv = XDR_PUTINT32(xdrs, i32p+1);
 224 #else
 225                 rv = XDR_PUTINT32(xdrs, i32p+1);
 226                 if (!rv)
 227                         return (rv);
 228                 rv = XDR_PUTINT32(xdrs, i32p);
 229 #endif
 230                 return (rv);
 231 #else
 232                 vd = *((struct vax_double *)dp);
 233                 for (i = 0, lim = dbl_limits;
 234                         i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
 235                         i++, lim++) {
 236                         if ((vd.mantissa4 == lim->d.mantissa4) &&
 237                                 (vd.mantissa3 == lim->d.mantissa3) &&
 238                                 (vd.mantissa2 == lim->d.mantissa2) &&
 239                                 (vd.mantissa1 == lim->d.mantissa1) &&
 240                                 (vd.exp == lim->d.exp)) {
 241                                 id = lim->ieee;
 242                                 goto shipit;
 243                         }
 244                 }
 245                 id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
 246                 id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
 247                 id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
 248                                 (vd.mantissa3 << 13) |
 249                                 ((vd.mantissa4 >> 3) & MASK(13));
 250         shipit:
 251                 id.sign = vd.sign;
 252                 lp = (int32_t *)&id;
 253                 return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp));
 254 #endif
 255
 256         case XDR_DECODE:
 257 #ifdef IEEEFP
 258                 i32p = (int32_t *)(void *)dp;
 259 #if BYTE_ORDER == BIG_ENDIAN
 260                 rv = XDR_GETINT32(xdrs, i32p);
 261                 if (!rv)
 262                         return (rv);
 263                 rv = XDR_GETINT32(xdrs, i32p+1);
 264 #else
 265                 rv = XDR_GETINT32(xdrs, i32p+1);
 266                 if (!rv)
 267                         return (rv);
 268                 rv = XDR_GETINT32(xdrs, i32p);
 269 #endif
 270                 return (rv);
 271 #else
 272                 lp = (int32_t *)&id;
 273                 if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp))
 274                         return (FALSE);
 275                 for (i = 0, lim = dbl_limits;
 276                         i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
 277                         i++, lim++) {
 278                         if ((id.mantissa2 == lim->ieee.mantissa2) &&
 279                                 (id.mantissa1 == lim->ieee.mantissa1) &&
 280                                 (id.exp == lim->ieee.exp)) {
 281                                 vd = lim->d;
 282                                 goto doneit;
 283                         }
 284                 }
 285                 vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
 286                 vd.mantissa1 = (id.mantissa1 >> 13);
 287                 vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
 288                                 (id.mantissa2 >> 29);
 289                 vd.mantissa3 = (id.mantissa2 >> 13);
 290                 vd.mantissa4 = (id.mantissa2 << 3);
 291         doneit:
 292                 vd.sign = id.sign;
 293                 *dp = *((double *)&vd);
 294                 return (TRUE);
 295 #endif
 296
 297         case XDR_FREE:
 298                 return (TRUE);
 299         }
 300         /* NOTREACHED */
 301         return (FALSE);
 302 }