xref: /netbsd-src/lib/libc/gdtoa/strtorQ.c (revision 9a9a41227b42868f516d4f928b32562ad0f5bc3b)
1 /* $NetBSD: strtorQ.c,v 1.5 2019/08/01 02:27:43 riastradh 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
ULtoQ(L,bits,expt,k)56 ULtoQ(L, bits, expt, k) ULong *L; ULong *bits; Long expt; int k;
57 #else
58 ULtoQ(ULong *L, ULong *bits, Long expt, 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) | ((expt + 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
strtorQ(s,sp,rounding,L)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 CONST FPI fpi0 = { 113, 1-16383-113+1, 32766-16383-113+1, 1, SI };
105 	CONST FPI *fpi;
106 	FPI fpi1;
107 	ULong bits[4];
108 	Long expt;
109 	int k;
110 
111 	fpi = &fpi0;
112 	if (rounding != FPI_Round_near) {
113 		fpi1 = fpi0;
114 		fpi1.rounding = rounding;
115 		fpi = &fpi1;
116 		}
117 	k = strtodg(s, sp, fpi, &expt, bits);
118 	if (k == STRTOG_NoMemory)
119 		return k;
120 	ULtoQ((ULong*)L, bits, expt, k);
121 	return k;
122 	}
123