lib/libc/gdtoa/strtorQ.c

   1 /* $NetBSD: strtorQ.c,v 1.3 2008/03/21 23:13:48 christos Exp $ */
   2
   3 /****************************************************************
   4
   5 The author of this software is David M. Gay.
   6
   7 Copyright (C) 1998, 2000 by Lucent Technologies
   8 All Rights Reserved
   9
  10 Permission to use, copy, modify, and distribute this software and
  11 its documentation for any purpose and without fee is hereby
  12 granted, provided that the above copyright notice appear in all
  13 copies and that both that the copyright notice and this
  14 permission notice and warranty disclaimer appear in supporting
  15 documentation, and that the name of Lucent or any of its entities
  16 not be used in advertising or publicity pertaining to
  17 distribution of the software without specific, written prior
  18 permission.
  19
  20 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  21 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
  22 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
  23 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  24 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
  25 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
  26 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
  27 THIS SOFTWARE.
  28
  29 ****************************************************************/
  30
  31 /* Please send bug reports to David M. Gay (dmg at acm dot org,
  32  * with " at " changed at "@" and " dot " changed to ".").      */
  33
  34 #include "gdtoaimp.h"
  35
  36 #undef _0
  37 #undef _1
  38
  39 /* one or the other of IEEE_BIG_ENDIAN or IEEE_LITTLE_ENDIAN should be #defined */
  40
  41 #ifdef IEEE_BIG_ENDIAN
  42 #define _0 0
  43 #define _1 1
  44 #define _2 2
  45 #define _3 3
  46 #endif
  47 #ifdef IEEE_LITTLE_ENDIAN
  48 #define _0 3
  49 #define _1 2
  50 #define _2 1
  51 #define _3 0
  52 #endif
  53
  54  void
  55 #ifdef KR_headers
  56 ULtoQ(L, bits, exp, k) ULong *L; ULong *bits; Long exp; int k;
  57 #else
  58 ULtoQ(ULong *L, ULong *bits, Long exp, int k)
  59 #endif
  60 {
  61         switch(k & STRTOG_Retmask) {
  62           case STRTOG_NoNumber:
  63           case STRTOG_Zero:
  64                 L[0] = L[1] = L[2] = L[3] = 0;
  65                 break;
  66
  67           case STRTOG_Normal:
  68           case STRTOG_NaNbits:
  69                 L[_3] = bits[0];
  70                 L[_2] = bits[1];
  71                 L[_1] = bits[2];
  72                 L[_0] = (bits[3] & ~0x10000) | ((exp + 0x3fff + 112) << 16);
  73                 break;
  74
  75           case STRTOG_Denormal:
  76                 L[_3] = bits[0];
  77                 L[_2] = bits[1];
  78                 L[_1] = bits[2];
  79                 L[_0] = bits[3];
  80                 break;
  81
  82           case STRTOG_Infinite:
  83                 L[_0] = 0x7fff0000;
  84                 L[_1] = L[_2] = L[_3] = 0;
  85                 break;
  86
  87           case STRTOG_NaN:
  88                 L[0] = ld_QNAN0;
  89                 L[1] = ld_QNAN1;
  90                 L[2] = ld_QNAN2;
  91                 L[3] = ld_QNAN3;
  92           }
  93         if (k & STRTOG_Neg)
  94                 L[_0] |= 0x80000000L;
  95         }
  96
  97  int
  98 #ifdef KR_headers
  99 strtorQ(s, sp, rounding, L) CONST char *s; char **sp; int rounding; void *L;
 100 #else
 101 strtorQ(CONST char *s, char **sp, int rounding, void *L)
 102 #endif
 103 {
 104         static FPI fpi0 = { 113, 1-16383-113+1, 32766-16383-113+1, 1, SI };
 105         FPI *fpi, fpi1;
 106         ULong bits[4];
 107         Long exp;
 108         int k;
 109
 110         fpi = &fpi0;
 111         if (rounding != FPI_Round_near) {
 112                 fpi1 = fpi0;
 113                 fpi1.rounding = rounding;
 114                 fpi = &fpi1;
 115                 }
 116         k = strtodg(s, sp, fpi, &exp, bits);
 117         if (k == STRTOG_NoMemory)
 118                 return k;
 119         ULtoQ((ULong*)L, bits, exp, k);
 120         return k;
 121         }