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  * $FreeBSD: src/lib/libc/xdr/xdr_float.c,v 1.7 1999/08/28 00:02:55 peter Exp $
  32  * $DragonFly: src/lib/libc/xdr/xdr_float.c,v 1.6 2006/07/27 00:43:17 corecode Exp $
  33  */
  34
  35 /*
  36  * xdr_float.c, Generic XDR routines impelmentation.
  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 <stdio.h>
  46 #include <sys/types.h>
  47 #include <sys/param.h>
  48 #include <rpc/types.h>
  49 #include <rpc/xdr.h>
  50
  51 /*
  52  * NB: Not portable.
  53  * This routine works on machines with IEEE754 FP and Vaxen.
  54  */
  55
  56 #if defined(__m68k__) || defined(__sparc__) || defined(__i386__) || \
  57     defined(__mips__) || defined(__ns32k__) || defined(__arm32__) || \
  58     defined(__ppc__) || defined(__amd64__)
  59 #include <machine/endian.h>
  60 #define IEEEFP
  61 #endif
  62
  63 #ifdef vax
  64
  65 /* What IEEE single precision floating point looks like on a Vax */
  66 struct  ieee_single {
  67         unsigned int    mantissa: 23;
  68         unsigned int    exp     : 8;
  69         unsigned int    sign    : 1;
  70 };
  71
  72 /* Vax single precision floating point */
  73 struct  vax_single {
  74         unsigned int    mantissa1 : 7;
  75         unsigned int    exp       : 8;
  76         unsigned int    sign      : 1;
  77         unsigned int    mantissa2 : 16;
  78 };
  79
  80 #define VAX_SNG_BIAS    0x81
  81 #define IEEE_SNG_BIAS   0x7f
  82
  83 static struct sgl_limits {
  84         struct vax_single s;
  85         struct ieee_single ieee;
  86 } sgl_limits[2] = {
  87         {{ 0x7f, 0xff, 0x0, 0xffff },   /* Max Vax */
  88         { 0x0, 0xff, 0x0 }},            /* Max IEEE */
  89         {{ 0x0, 0x0, 0x0, 0x0 },        /* Min Vax */
  90         { 0x0, 0x0, 0x0 }}              /* Min IEEE */
  91 };
  92 #endif /* vax */
  93
  94 bool_t
  95 xdr_float(XDR *xdrs, float *fp)
  96 {
  97 #ifdef IEEEFP
  98         bool_t rv;
  99         long tmpl;
 100 #else
 101         struct ieee_single is;
 102         struct vax_single vs, *vsp;
 103         struct sgl_limits *lim;
 104         int i;
 105 #endif
 106         switch (xdrs->x_op) {
 107
 108         case XDR_ENCODE:
 109 #ifdef IEEEFP
 110                 tmpl = *(int32_t *)fp;
 111                 return (XDR_PUTLONG(xdrs, &tmpl));
 112 #else
 113                 vs = *((struct vax_single *)fp);
 114                 for (i = 0, lim = sgl_limits;
 115                         i < sizeof(sgl_limits)/sizeof(struct sgl_limits);
 116                         i++, lim++) {
 117                         if ((vs.mantissa2 == lim->s.mantissa2) &&
 118                                 (vs.exp == lim->s.exp) &&
 119                                 (vs.mantissa1 == lim->s.mantissa1)) {
 120                                 is = lim->ieee;
 121                                 goto shipit;
 122                         }
 123                 }
 124                 is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS;
 125                 is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2;
 126         shipit:
 127                 is.sign = vs.sign;
 128                 return (XDR_PUTLONG(xdrs, (long *)&is));
 129 #endif
 130
 131         case XDR_DECODE:
 132 #ifdef IEEEFP
 133                 rv = XDR_GETLONG(xdrs, &tmpl);
 134                 *(int32_t *)fp = tmpl;
 135                 return (rv);
 136 #else
 137                 vsp = (struct vax_single *)fp;
 138                 if (!XDR_GETLONG(xdrs, (long *)&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         return (FALSE);
 161 }
 162
 163 #ifdef 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         long tmpl;
 206 #else
 207         long *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 *)dp;
 219 #if BYTE_ORDER == BIG_ENDIAN
 220                 tmpl = *i32p++;
 221                 rv = XDR_PUTLONG(xdrs, &tmpl);
 222                 if (!rv)
 223                         return (rv);
 224                 tmpl = *i32p;
 225                 rv = XDR_PUTLONG(xdrs, &tmpl);
 226 #else
 227                 tmpl = *(i32p+1);
 228                 rv = XDR_PUTLONG(xdrs, &tmpl);
 229                 if (!rv)
 230                         return (rv);
 231                 tmpl = *i32p;
 232                 rv = XDR_PUTLONG(xdrs, &tmpl);
 233 #endif
 234                 return (rv);
 235 #else
 236                 vd = *((struct vax_double *)dp);
 237                 for (i = 0, lim = dbl_limits;
 238                         i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
 239                         i++, lim++) {
 240                         if ((vd.mantissa4 == lim->d.mantissa4) &&
 241                                 (vd.mantissa3 == lim->d.mantissa3) &&
 242                                 (vd.mantissa2 == lim->d.mantissa2) &&
 243                                 (vd.mantissa1 == lim->d.mantissa1) &&
 244                                 (vd.exp == lim->d.exp)) {
 245                                 id = lim->ieee;
 246                                 goto shipit;
 247                         }
 248                 }
 249                 id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS;
 250                 id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3);
 251                 id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) |
 252                                 (vd.mantissa3 << 13) |
 253                                 ((vd.mantissa4 >> 3) & MASK(13));
 254         shipit:
 255                 id.sign = vd.sign;
 256                 lp = (long *)&id;
 257                 return (XDR_PUTLONG(xdrs, lp++) && XDR_PUTLONG(xdrs, lp));
 258 #endif
 259
 260         case XDR_DECODE:
 261 #ifdef IEEEFP
 262                 i32p = (int32_t *)dp;
 263 #if BYTE_ORDER == BIG_ENDIAN
 264                 rv = XDR_GETLONG(xdrs, &tmpl);
 265                 *i32p++ = tmpl;
 266                 if (!rv)
 267                         return (rv);
 268                 rv = XDR_GETLONG(xdrs, &tmpl);
 269                 *i32p = tmpl;
 270 #else
 271                 rv = XDR_GETLONG(xdrs, &tmpl);
 272                 *(i32p+1) = tmpl;
 273                 if (!rv)
 274                         return (rv);
 275                 rv = XDR_GETLONG(xdrs, &tmpl);
 276                 *i32p = tmpl;
 277 #endif
 278                 return (rv);
 279 #else
 280                 lp = (long *)&id;
 281                 if (!XDR_GETLONG(xdrs, lp++) || !XDR_GETLONG(xdrs, lp))
 282                         return (FALSE);
 283                 for (i = 0, lim = dbl_limits;
 284                         i < sizeof(dbl_limits)/sizeof(struct dbl_limits);
 285                         i++, lim++) {
 286                         if ((id.mantissa2 == lim->ieee.mantissa2) &&
 287                                 (id.mantissa1 == lim->ieee.mantissa1) &&
 288                                 (id.exp == lim->ieee.exp)) {
 289                                 vd = lim->d;
 290                                 goto doneit;
 291                         }
 292                 }
 293                 vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS;
 294                 vd.mantissa1 = (id.mantissa1 >> 13);
 295                 vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) |
 296                                 (id.mantissa2 >> 29);
 297                 vd.mantissa3 = (id.mantissa2 >> 13);
 298                 vd.mantissa4 = (id.mantissa2 << 3);
 299         doneit:
 300                 vd.sign = id.sign;
 301                 *dp = *((double *)&vd);
 302                 return (TRUE);
 303 #endif
 304
 305         case XDR_FREE:
 306                 return (TRUE);
 307         }
 308         return (FALSE);
 309 }