1/* $NetBSD: hexnan.c,v 1.4 2011/03/20 23:15:35 christos Exp $ */
2
3/****************************************************************
4
5The author of this software is David M. Gay.
6
7Copyright (C) 2000 by Lucent Technologies
8All Rights Reserved
9
10Permission to use, copy, modify, and distribute this software and
11its documentation for any purpose and without fee is hereby
12granted, provided that the above copyright notice appear in all
13copies and that both that the copyright notice and this
14permission notice and warranty disclaimer appear in supporting
15documentation, and that the name of Lucent or any of its entities
16not be used in advertising or publicity pertaining to
17distribution of the software without specific, written prior
18permission.
19
20LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
21INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
22IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
23SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
24WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
25IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
26ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
27THIS 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 static void
37#ifdef KR_headers
38L_shift(x, x1, i) ULong *x; ULong *x1; int i;
39#else
40L_shift(ULong *x, ULong *x1, int i)
41#endif
42{
43	int j;
44
45	i = 8 - i;
46	i <<= 2;
47	j = ULbits - i;
48	do {
49		*x |= x[1] << j;
50		x[1] >>= i;
51		} while(++x < x1);
52	}
53
54 int
55#ifdef KR_headers
56hexnan(sp, fpi, x0)
57	CONST char **sp; CONST FPI *fpi; ULong *x0;
58#else
59hexnan( CONST char **sp, CONST FPI *fpi, ULong *x0)
60#endif
61{
62	ULong c, h, *x, *x1, *xe;
63	CONST char *s;
64	int havedig, hd0, i, nbits;
65
66	if (!hexdig['0'])
67		hexdig_init_D2A();
68	nbits = fpi->nbits;
69	x = x0 + ((unsigned int)nbits >> kshift);
70	if (nbits & kmask)
71		x++;
72	*--x = 0;
73	x1 = xe = x;
74	havedig = hd0 = i = 0;
75	s = *sp;
76	/* allow optional initial 0x or 0X */
77	while((c = *(CONST unsigned char*)(s+1)) && c <= ' ')
78		++s;
79	if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
80	 && *(CONST unsigned char*)(s+3) > ' ')
81		s += 2;
82	while((c = *(CONST unsigned char*)++s) != '\0') {
83		if (!(h = hexdig[c])) {
84			if (c <= ' ') {
85				if (hd0 < havedig) {
86					if (x < x1 && i < 8)
87						L_shift(x, x1, i);
88					if (x <= x0) {
89						i = 8;
90						continue;
91						}
92					hd0 = havedig;
93					*--x = 0;
94					x1 = x;
95					i = 0;
96					}
97				while(*(CONST unsigned char*)(s+1) <= ' ')
98					++s;
99				if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
100				 && *(CONST unsigned char*)(s+3) > ' ')
101					s += 2;
102				continue;
103				}
104			if (/*(*/ c == ')' && havedig) {
105				*sp = s + 1;
106				break;
107				}
108#ifndef GDTOA_NON_PEDANTIC_NANCHECK
109			do {
110				if (/*(*/ c == ')') {
111					*sp = s + 1;
112					break;
113					}
114				} while((c = *++s) != '\0');
115#endif
116			return STRTOG_NaN;
117			}
118		havedig++;
119		if (++i > 8) {
120			if (x <= x0)
121				continue;
122			i = 1;
123			*--x = 0;
124			}
125		*x = (*x << 4) | (h & 0xf);
126		}
127	if (!havedig)
128		return STRTOG_NaN;
129	if (x < x1 && i < 8)
130		L_shift(x, x1, i);
131	if (x > x0) {
132		x1 = x0;
133		do *x1++ = *x++;
134			while(x <= xe);
135		do *x1++ = 0;
136			while(x1 <= xe);
137		}
138	else {
139		/* truncate high-order word if necessary */
140		if ( (i = nbits & (ULbits-1)) !=0)
141			*xe &= ((ULong)0xffffffff) >> (ULbits - i);
142		}
143	for(x1 = xe;; --x1) {
144		if (*x1 != 0)
145			break;
146		if (x1 == x0) {
147			*x1 = 1;
148			break;
149			}
150		}
151	return STRTOG_NaNbits;
152	}
153