1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/* mpfr_set_str_binary -- set a floating-point number from a binary string
Copyright 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of the MPFR Library.
The MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version.
The MPFR Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the MPFR Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#define MPFR_NEED_LONGLONG_H
#include "mpfr-impl.h"
/* Currently the number should be of the form +/- xxxx.xxxxxxEyy, with
decimal exponent. The mantissa of x is supposed to be large enough
to hold all the bits of str. */
void
mpfr_set_str_binary (mpfr_ptr x, const char *str)
{
char *str2, *str0, negative = 0;
unsigned long j, l, k = 0, xsize, cnt, alloc;
mp_limb_t *xp;
long expn = 0, e;
char *endstr2;
xp = MPFR_MANT(x);
xsize = MPFR_LIMB_SIZE(x);
alloc = strlen(str) + 1;
if (*str == '-')
{
negative = 1;
str++;
}
else if (*str == '+')
str++;
if (*str == 'N')
{
MPFR_SET_NAN(x);
__gmpfr_flags |= MPFR_FLAGS_NAN;
return;
}
if (*str == 'I')
{
MPFR_SET_INF(x);
if (negative)
MPFR_SET_NEG(x);
else
MPFR_SET_POS(x);
/*if (MPFR_IS_STRICTNEG(x) != negative)
MPFR_CHANGE_SIGN(x);*/
return;
}
MPFR_CLEAR_FLAGS(x);
str0 = str2 = (char *) (*__gmp_allocate_func) (alloc);
while (*str == '0')
str++;
while (*str == '0' || *str == '1')
{
*(str2++) = *(str++);
k++;
}
if (*str == '.')
{
str++;
while (*str == '0' || *str == '1')
{
*(str2++) = *(str++);
}
}
if (*str == 'e' || *str == 'E')
{
char *end;
e = strtol (++str, &end, 10); /* signed exponent after 'e' or 'E' */
MPFR_ASSERTN (*end == '\0' && errno != ERANGE);
expn = k + e;
MPFR_ASSERTN (expn >= e);
}
else
expn = k;
endstr2 = str2;
l = endstr2 - str0; /* length of mantissa */
if (l == 0)
{ /* input is zero */
MPFR_SET_ZERO(x);
}
else
{
l = (l - 1) / BITS_PER_MP_LIMB + 1;
str2 = str0;
MPFR_ASSERTN (l <= xsize);
/* str2[0]..endstr2[-1] contains the mantissa */
for (k = 1; k <= l; k++)
{
j = 0;
xp[xsize - k] = 0;
while ((str2 < endstr2) && (j < BITS_PER_MP_LIMB))
{
xp[xsize - k] = (xp[xsize - k] << 1) + (*str2 - '0');
str2++; j++;
}
xp[xsize - k] <<= (BITS_PER_MP_LIMB - j);
}
for (; k <= xsize; k++)
xp[xsize - k] = 0;
count_leading_zeros(cnt, xp[xsize - 1]);
if (cnt)
mpn_lshift(xp, xp, xsize, cnt);
MPFR_SET_EXP (x, expn - cnt);
if (negative)
MPFR_SET_NEG(x);
else
MPFR_SET_POS(x);
}
(*__gmp_free_func) (str0, alloc);
/* May change to take into account : syntax errors, overflow in exponent,
string truncated because of size of x */
}
|
