1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 23 /* 24 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 25 * Use is subject to license terms. 26 */ 27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */ 28 /* All Rights Reserved */ 29 /* 30 * Portions of this source code were derived from Berkeley 31 * 4.3 BSD under license from the Regents of the University of 32 * California. 33 */ 34 35 #pragma ident "%Z%%M% %I% %E% SMI" 36 37 /* 38 * xdr_float.c, Generic XDR routines impelmentation. 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 <sys/types.h> 46 #include <stdio.h> 47 #include <rpc/types.h> 48 #include <rpc/xdr.h> 49 50 /* 51 * This routine works on Suns, 3b2, 68000s, 386 and Vaxen in a manner 52 * which is very efficient as bit twiddling is all that is needed. All 53 * other machines can use this code but the code is inefficient as 54 * various mathematical operations are used to generate the ieee format. 55 * In addition rounding errors may occur due to the calculations involved. 56 * To be most efficient, new machines should have their own ifdefs. 57 * The encoding routines will fail if the machines try to encode a 58 * float/double whose value can not be represented by the ieee format, 59 * e.g. the exponent is too big/small. 60 * ieee largest float = (2 ^ 128) * 0x1.fffff 61 * ieee smallest float = (2 ^ -127) * 0x1.00000 62 * ieee largest double = (2 ^ 1024) * 0x1.fffff 63 * ieee smallest double = (2 ^ -1023) * 0x1.00000 64 * The decoding routines assumes that the receiving machine can handle 65 * floats/doubles as large/small as the values stated above. If you 66 * use a machine which can not represent these values, you will need 67 * to put ifdefs in the decode sections to identify areas of failure. 68 */ 69 70 #if defined(vax) 71 72 /* 73 * What IEEE single precision floating point looks like this on a 74 * vax. 75 */ 76 77 struct ieee_single { 78 unsigned int mantissa: 23; 79 unsigned int exp : 8; 80 unsigned int sign : 1; 81 }; 82 83 #define IEEE_SNG_BIAS 0x7f 84 #define VAX_SNG_BIAS 0x81 85 86 87 /* Vax single precision floating point */ 88 struct vax_single { 89 unsigned int mantissa1 : 7; 90 unsigned int exp : 8; 91 unsigned int sign : 1; 92 unsigned int mantissa2 : 16; 93 }; 94 95 #define VAX_SNG_BIAS 0x81 96 97 static struct sgl_limits { 98 struct vax_single s; 99 struct ieee_single ieee; 100 } sgl_limits[2] = { 101 {{ 0x7f, 0xff, 0x0, 0xffff }, /* Max Vax */ 102 { 0x0, 0xff, 0x0 }}, /* Max IEEE */ 103 {{ 0x0, 0x0, 0x0, 0x0 }, /* Min Vax */ 104 { 0x0, 0x0, 0x0 }} /* Min IEEE */ 105 }; 106 #endif /* vax */ 107 108 bool_t 109 xdr_float(XDR *xdrs, float *fp) 110 { 111 #if defined(vax) 112 struct ieee_single is; 113 struct vax_single vs, *vsp; 114 struct sgl_limits *lim; 115 size_t i; 116 #endif 117 118 switch (xdrs->x_op) { 119 120 case XDR_ENCODE: 121 #if defined(mc68000) || defined(sparc) || defined(u3b2) || \ 122 defined(u3b15) || defined(i386) 123 return (XDR_PUTINT32(xdrs, (int *)fp)); 124 #else 125 #if defined(vax) 126 vs = *((struct vax_single *)fp); 127 if ((vs.exp == 1) || (vs.exp == 2)) { 128 /* map these to subnormals */ 129 is.exp = 0; 130 is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2; 131 /* lose some precision */ 132 is.mantissa >>= 3 - vs.exp; 133 is.mantissa += (1 << (20 + vs.exp)); 134 goto shipit; 135 } 136 for (i = 0, lim = sgl_limits; 137 i < (int)(sizeof (sgl_limits) / 138 sizeof (struct sgl_limits)); 139 i++, lim++) { 140 if ((vs.mantissa2 == lim->s.mantissa2) && 141 (vs.exp == lim->s.exp) && 142 (vs.mantissa1 == lim->s.mantissa1)) { 143 is = lim->ieee; 144 goto shipit; 145 } 146 } 147 is.exp = vs.exp - VAX_SNG_BIAS + IEEE_SNG_BIAS; 148 is.mantissa = (vs.mantissa1 << 16) | vs.mantissa2; 149 shipit: 150 is.sign = vs.sign; 151 return (XDR_PUTINT32(xdrs, (int32_t *)&is)); 152 #else 153 { 154 /* 155 * Every machine can do this, its just not very efficient. 156 * In addtion, some rounding errors may occur do to the 157 * calculations involved. 158 */ 159 float f; 160 int neg = 0; 161 int exp = 0; 162 int32_t val; 163 164 f = *fp; 165 if (f == 0) { 166 val = 0; 167 return (XDR_PUTINT32(xdrs, &val)); 168 } 169 if (f < 0) { 170 f = 0 - f; 171 neg = 1; 172 } 173 while (f < 1) { 174 f = f * 2; 175 --exp; 176 } 177 while (f >= 2) { 178 f = f/2; 179 ++exp; 180 } 181 if ((exp > 128) || (exp < -127)) { 182 /* over or under flowing ieee exponent */ 183 return (FALSE); 184 } 185 val = neg; 186 val = val << 8; /* for the exponent */ 187 val += 127 + exp; /* 127 is the bias */ 188 val = val << 23; /* for the mantissa */ 189 val += (int32_t)((f - 1) * 8388608); /* 2 ^ 23 */ 190 return (XDR_PUTINT32(xdrs, &val)); 191 } 192 #endif 193 #endif 194 195 case XDR_DECODE: 196 #if defined(mc68000) || defined(sparc) || defined(u3b2) || \ 197 defined(u3b15) || defined(i386) 198 return (XDR_GETINT32(xdrs, (int *)fp)); 199 #else 200 #if defined(vax) 201 vsp = (struct vax_single *)fp; 202 if (!XDR_GETINT32(xdrs, (int32_t *)&is)) 203 return (FALSE); 204 205 for (i = 0, lim = sgl_limits; 206 i < (int)(sizeof (sgl_limits) / 207 sizeof (struct sgl_limits)); 208 i++, lim++) { 209 if ((is.exp == lim->ieee.exp) && 210 (is.mantissa == lim->ieee.mantissa)) { 211 *vsp = lim->s; 212 goto doneit; 213 } else if ((is.exp == 0) && (lim->ieee.exp == 0)) { 214 /* Special Case */ 215 unsigned tmp = is.mantissa >> 20; 216 if (tmp >= 4) { 217 vsp->exp = 2; 218 } else if (tmp >= 2) { 219 vsp->exp = 1; 220 } else { 221 *vsp = min.s; 222 break; 223 } /* else */ 224 tmp = is.mantissa - (1 << (20 + vsp->exp)); 225 tmp <<= 3 - vsp->exp; 226 vsp->mantissa2 = tmp; 227 vsp->mantissa1 = (tmp >> 16); 228 goto doneit; 229 } 230 vsp->exp = is.exp - IEEE_SNG_BIAS + VAX_SNG_BIAS; 231 vsp->mantissa2 = is.mantissa; 232 vsp->mantissa1 = (is.mantissa >> 16); 233 doneit: 234 vsp->sign = is.sign; 235 return (TRUE); 236 #else 237 { 238 /* 239 * Every machine can do this, its just not very 240 * efficient. It assumes that the decoding machine's 241 * float can represent any value in the range of 242 * ieee largest float = (2 ^ 128) * 0x1.fffff 243 * to 244 * ieee smallest float = (2 ^ -127) * 0x1.00000 245 * In addtion, some rounding errors may occur do to the 246 * calculations involved. 247 */ 248 float f; 249 int neg = 0; 250 int exp = 0; 251 int32_t val; 252 253 if (!XDR_GETINT32(xdrs, (int32_t *)&val)) 254 return (FALSE); 255 neg = val & 0x80000000; 256 exp = (val & 0x7f800000) >> 23; 257 exp -= 127; /* subtract exponent base */ 258 f = (val & 0x007fffff) * 0.00000011920928955078125; 259 /* 2 ^ -23 */ 260 f++; 261 while (exp != 0) { 262 if (exp < 0) { 263 f = f/2.0; 264 ++exp; 265 } else { 266 f = f * 2.0; 267 --exp; 268 } 269 } 270 if (neg) 271 f = 0 - f; 272 *fp = f; 273 } 274 return (TRUE); 275 #endif 276 #endif 277 278 case XDR_FREE: 279 return (TRUE); 280 } 281 return (FALSE); 282 } 283 284 /* 285 * This routine works on Suns (Sky / 68000's) and Vaxen. 286 */ 287 288 #if defined(vax) 289 /* What IEEE double precision floating point looks like on a Vax */ 290 struct ieee_double { 291 unsigned int mantissa1 : 20; 292 unsigned int exp : 11; 293 unsigned int sign : 1; 294 unsigned int mantissa2 : 32; 295 }; 296 297 /* Vax double precision floating point */ 298 struct vax_double { 299 unsigned int mantissa1 : 7; 300 unsigned int exp : 8; 301 unsigned int sign : 1; 302 unsigned int mantissa2 : 16; 303 unsigned int mantissa3 : 16; 304 unsigned int mantissa4 : 16; 305 }; 306 307 #define VAX_DBL_BIAS 0x81 308 #define IEEE_DBL_BIAS 0x3ff 309 #define MASK(nbits) ((1 << nbits) - 1) 310 311 static struct dbl_limits { 312 struct vax_double d; 313 struct ieee_double ieee; 314 } dbl_limits[2] = { 315 {{ 0x7f, 0xff, 0x0, 0xffff, 0xffff, 0xffff }, /* Max Vax */ 316 { 0x0, 0x7ff, 0x0, 0x0 }}, /* Max IEEE */ 317 {{ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, /* Min Vax */ 318 { 0x0, 0x0, 0x0, 0x0 }} /* Min IEEE */ 319 }; 320 321 #endif /* vax */ 322 323 324 bool_t 325 xdr_double(XDR *xdrs, double *dp) 326 { 327 int *lp; 328 #if defined(vax) 329 struct ieee_double id; 330 struct vax_double vd; 331 struct dbl_limits *lim; 332 size_t i; 333 #endif 334 335 switch (xdrs->x_op) { 336 337 case XDR_ENCODE: 338 #if defined(mc68000) || defined(u3b2) || defined(u3b15) || \ 339 defined(_LONG_LONG_HTOL) 340 lp = (int *)dp; 341 return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp)); 342 #else 343 #if defined(_LONG_LONG_LTOH) 344 lp = (int *)dp; 345 lp++; 346 return (XDR_PUTINT32(xdrs, lp--) && XDR_PUTINT32(xdrs, lp)); 347 #else 348 #if defined(vax) 349 vd = *((struct vax_double *)dp); 350 for (i = 0, lim = dbl_limits; 351 i < (int)(sizeof (dbl_limits) / 352 sizeof (struct dbl_limits)); 353 i++, lim++) { 354 if ((vd.mantissa4 == lim->d.mantissa4) && 355 (vd.mantissa3 == lim->d.mantissa3) && 356 (vd.mantissa2 == lim->d.mantissa2) && 357 (vd.mantissa1 == lim->d.mantissa1) && 358 (vd.exp == lim->d.exp)) { 359 id = lim->ieee; 360 goto shipit; 361 } 362 } 363 id.exp = vd.exp - VAX_DBL_BIAS + IEEE_DBL_BIAS; 364 id.mantissa1 = (vd.mantissa1 << 13) | (vd.mantissa2 >> 3); 365 id.mantissa2 = ((vd.mantissa2 & MASK(3)) << 29) | 366 (vd.mantissa3 << 13) | 367 ((vd.mantissa4 >> 3) & MASK(13)); 368 shipit: 369 id.sign = vd.sign; 370 lp = (int32_t *)&id; 371 #else 372 { 373 /* 374 * Every machine can do this, its just not very efficient. 375 * In addtion, some rounding errors may occur do to the 376 * calculations involved. 377 */ 378 double d; 379 int neg = 0; 380 int exp = 0; 381 int32_t val[2]; 382 383 d = *dp; 384 if (d == 0) { 385 val[0] = 0; 386 val[1] = 0; 387 lp = val; 388 return (XDR_PUTINT32(xdrs, lp++) && 389 XDR_PUTINT32(xdrs, lp)); 390 } 391 if (d < 0) { 392 d = 0 - d; 393 neg = 1; 394 } 395 while (d < 1) { 396 d = d * 2; 397 --exp; 398 } 399 while (d >= 2) { 400 d = d/2; 401 ++exp; 402 } 403 if ((exp > 1024) || (exp < -1023)) { 404 /* over or under flowing ieee exponent */ 405 return (FALSE); 406 } 407 val[0] = neg; 408 val[0] = val[0] << 11; /* for the exponent */ 409 val[0] += 1023 + exp; /* 1023 is the bias */ 410 val[0] = val[0] << 20; /* for the mantissa */ 411 val[0] += (int32_t)((d - 1) * 1048576); /* 2 ^ 20 */ 412 val[1] += (int32_t)((((d - 1) * 1048576) - val[0]) 413 * 4294967296); 414 /* 2 ^ 32 */ 415 lp = val; 416 } 417 #endif 418 return (XDR_PUTINT32(xdrs, lp++) && XDR_PUTINT32(xdrs, lp)); 419 #endif 420 #endif 421 422 case XDR_DECODE: 423 #if defined(mc68000) || defined(u3b2) || defined(u3b15) || \ 424 defined(_LONG_LONG_HTOL) 425 lp = (int *)dp; 426 return (XDR_GETINT32(xdrs, lp++) && XDR_GETINT32(xdrs, lp)); 427 #else 428 #if defined(_LONG_LONG_LTOH) 429 lp = (int *)dp; 430 lp++; 431 return (XDR_GETINT32(xdrs, lp--) && XDR_GETINT32(xdrs, lp)); 432 #else 433 #if defined(vax) 434 lp = (int32_t *)&id; 435 if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp)) 436 return (FALSE); 437 for (i = 0, lim = dbl_limits; 438 i < sizeof (dbl_limits)/sizeof (struct dbl_limits); 439 i++, lim++) { 440 if ((id.mantissa2 == lim->ieee.mantissa2) && 441 (id.mantissa1 == lim->ieee.mantissa1) && 442 (id.exp == lim->ieee.exp)) { 443 vd = lim->d; 444 goto doneit; 445 } 446 } 447 vd.exp = id.exp - IEEE_DBL_BIAS + VAX_DBL_BIAS; 448 vd.mantissa1 = (id.mantissa1 >> 13); 449 vd.mantissa2 = ((id.mantissa1 & MASK(13)) << 3) | 450 (id.mantissa2 >> 29); 451 vd.mantissa3 = (id.mantissa2 >> 13); 452 vd.mantissa4 = (id.mantissa2 << 3); 453 doneit: 454 vd.sign = id.sign; 455 *dp = *((double *)&vd); 456 return (TRUE); 457 #else 458 { 459 /* 460 * Every machine can do this, its just not very 461 * efficient. It assumes that the decoding machine's 462 * double can represent any value in the range of 463 * ieee largest double = (2 ^ 1024) * 0x1.fffffffffffff 464 * to 465 * ieee smallest double = (2 ^ -1023) * 0x1.0000000000000 466 * In addtion, some rounding errors may occur do to the 467 * calculations involved. 468 */ 469 double d; 470 int neg = 0; 471 int exp = 0; 472 int32_t val[2]; 473 474 lp = val; 475 if (!XDR_GETINT32(xdrs, lp++) || !XDR_GETINT32(xdrs, lp)) 476 return (FALSE); 477 neg = val[0] & 0x80000000; 478 exp = (val[0] & 0x7ff00000) >> 20; 479 exp -= 1023; /* subtract exponent base */ 480 d = (val[0] & 0x000fffff) * 0.00000095367431640625; 481 /* 2 ^ -20 */ 482 d += (val[1] * 0.0000000000000002220446049250313); 483 /* 2 ^ -52 */ 484 d++; 485 while (exp != 0) { 486 if (exp < 0) { 487 d = d/2.0; 488 ++exp; 489 } else { 490 d = d * 2.0; 491 --exp; 492 } 493 } 494 if (neg) 495 d = 0 - d; 496 *dp = d; 497 } 498 #endif 499 #endif 500 #endif 501 502 case XDR_FREE: 503 return (TRUE); 504 } 505 return (FALSE); 506 } 507 508 /* ARGSUSED */ 509 bool_t 510 xdr_quadruple(XDR *xdrs, long double *fp) 511 { 512 /* 513 * The Sparc uses IEEE FP encoding, so just do a byte copy 514 */ 515 516 #if !defined(sparc) 517 return (FALSE); 518 #else 519 switch (xdrs->x_op) { 520 case XDR_ENCODE: 521 return (XDR_PUTBYTES(xdrs, (char *)fp, sizeof (long double))); 522 case XDR_DECODE: 523 return (XDR_GETBYTES(xdrs, (char *)fp, sizeof (long double))); 524 case XDR_FREE: 525 return (TRUE); 526 } 527 return (FALSE); 528 #endif 529 } 530