xref: /freebsd/contrib/gdtoa/strtorx.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /****************************************************************
2 
3 The author of this software is David M. Gay.
4 
5 Copyright (C) 1998, 2000 by Lucent Technologies
6 All Rights Reserved
7 
8 Permission to use, copy, modify, and distribute this software and
9 its documentation for any purpose and without fee is hereby
10 granted, provided that the above copyright notice appear in all
11 copies and that both that the copyright notice and this
12 permission notice and warranty disclaimer appear in supporting
13 documentation, and that the name of Lucent or any of its entities
14 not be used in advertising or publicity pertaining to
15 distribution of the software without specific, written prior
16 permission.
17 
18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
25 THIS SOFTWARE.
26 
27 ****************************************************************/
28 
29 /* Please send bug reports to David M. Gay (dmg at acm dot org,
30  * with " at " changed at "@" and " dot " changed to ".").	*/
31 
32 /* $FreeBSD$ */
33 
34 #include "gdtoaimp.h"
35 
36 #undef _0
37 #undef _1
38 
39 /* one or the other of IEEE_MC68k or IEEE_8087 should be #defined */
40 
41 #ifdef IEEE_MC68k
42 #define _0 0
43 #define _1 1
44 #define _2 2
45 #define _3 3
46 #define _4 4
47 #endif
48 #ifdef IEEE_8087
49 #define _0 4
50 #define _1 3
51 #define _2 2
52 #define _3 1
53 #define _4 0
54 #endif
55 
56  void
57 #ifdef KR_headers
58 ULtox(L, bits, exp, k) UShort *L; ULong *bits; Long exp; int k;
59 #else
60 ULtox(UShort *L, ULong *bits, Long exp, int k)
61 #endif
62 {
63 	switch(k & STRTOG_Retmask) {
64 	  case STRTOG_NoNumber:
65 	  case STRTOG_Zero:
66 		L[0] = L[1] = L[2] = L[3] = L[4] = 0;
67 		break;
68 
69 	  case STRTOG_Denormal:
70 		L[_0] = 0;
71 		goto normal_bits;
72 
73 	  case STRTOG_Normal:
74 		L[_0] = exp + 0x3fff + 63;
75  normal_bits:
76 		L[_4] = (UShort)bits[0];
77 		L[_3] = (UShort)(bits[0] >> 16);
78 		L[_2] = (UShort)bits[1];
79 		L[_1] = (UShort)(bits[1] >> 16);
80 		break;
81 
82 	  case STRTOG_NaNbits:
83 		L[_0] = exp + 0x3fff + 63;
84 		L[_4] = (UShort)bits[0];
85 		L[_3] = (UShort)(bits[0] >> 16);
86 		L[_2] = (UShort)bits[1];
87 		L[_1] = (UShort)((bits[1] >> 16) | (3 << 14));
88 		break;
89 
90 	  case STRTOG_Infinite:
91 		L[_0] = 0x7fff;
92 		L[_1] = L[_2] = L[_3] = L[_4] = 0;
93 		break;
94 
95 	  case STRTOG_NaN:
96 		L[0] = ldus_QNAN0;
97 		L[1] = ldus_QNAN1;
98 		L[2] = ldus_QNAN2;
99 		L[3] = ldus_QNAN3;
100 		L[4] = ldus_QNAN4;
101 	  }
102 	if (k & STRTOG_Neg)
103 		L[_0] |= 0x8000;
104 	}
105 
106  int
107 #ifdef KR_headers
108 strtorx(s, sp, rounding, L) CONST char *s; char **sp; int rounding; void *L;
109 #else
110 strtorx(CONST char *s, char **sp, int rounding, void *L)
111 #endif
112 {
113 	static FPI fpi0 = { 64, 1-16383-64+1, 32766 - 16383 - 64 + 1, 1, SI };
114 	FPI *fpi, fpi1;
115 	ULong bits[2];
116 	Long exp;
117 	int k;
118 
119 	fpi = &fpi0;
120 	if (rounding != FPI_Round_near) {
121 		fpi1 = fpi0;
122 		fpi1.rounding = rounding;
123 		fpi = &fpi1;
124 		}
125 	k = strtodg(s, sp, fpi, &exp, bits);
126 	ULtox((UShort*)L, bits, exp, k);
127 	return k;
128 	}
129