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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/*
* Copyright (C) 1987-2008 Sun Microsystems, Inc. All Rights Reserved.
* Copyright (C) 2008-2011 Robert Ancell
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation, either version 2 of the License, or (at your option) any later
* version. See http://www.gnu.org/copyleft/gpl.html the full text of the
* license.
*/
#include <stdio.h>
#include "mp.h"
#include "mp-private.h"
#include "mp-serializer.h"
// FIXME: Make dynamic
#define MAX_DIGITS 1000
static char digits[] = "0123456789ABCDEF";
static int hex_to_int(char digit)
{
if (digit >= '0' && digit <= '9')
return digit - '0';
if (digit >= 'A' && digit <= 'F')
return digit - 'A' + 10;
if (digit >= 'a' && digit <= 'f')
return digit - 'a' + 10;
return 0;
}
static gchar *
to_hex_string(const MPNumber *x)
{
MpSerializer *serializer;
gchar *result;
serializer = mp_serializer_new(MP_DISPLAY_FORMAT_FIXED, 16, 0);
result = mp_serializer_to_string(serializer, x);
g_object_unref(serializer);
return result;
}
static void
mp_bitwise(const MPNumber *x, const MPNumber *y, int (*bitwise_operator)(int, int), MPNumber *z, int wordlen)
{
char *text1, *text2, text_out[MAX_DIGITS], text_out2[MAX_DIGITS];
int offset1, offset2, offset_out;
text1 = to_hex_string(x);
text2 = to_hex_string(y);
offset1 = strlen(text1) - 1;
offset2 = strlen(text2) - 1;
offset_out = wordlen / 4 - 1;
if (offset_out <= 0) {
offset_out = offset1 > offset2 ? offset1 : offset2;
}
if (offset_out > 0 && (offset_out < offset1 || offset_out < offset2)) {
g_free(text1);
g_free(text2);
mp_set_from_integer(0, z);
mperr("Overflow. Try a bigger word size");
return;
}
/* Perform bitwise operator on each character from right to left */
for (text_out[offset_out+1] = '\0'; offset_out >= 0; offset_out--) {
int v1 = 0, v2 = 0;
if (offset1 >= 0) {
v1 = hex_to_int(text1[offset1]);
offset1--;
}
if (offset2 >= 0) {
v2 = hex_to_int(text2[offset2]);
offset2--;
}
text_out[offset_out] = digits[bitwise_operator(v1, v2)];
}
snprintf(text_out2, MAX_DIGITS, "%s", text_out);
mp_set_from_string(text_out2, 16, z);
g_free(text1);
g_free(text2);
}
static int mp_bitwise_and(int v1, int v2) { return v1 & v2; }
static int mp_bitwise_or(int v1, int v2) { return v1 | v2; }
static int mp_bitwise_xor(int v1, int v2) { return v1 ^ v2; }
static int mp_bitwise_not(int v1, int dummy) { return v1 ^ 0xF; }
bool
mp_is_overflow (const MPNumber *x, int wordlen)
{
MPNumber tmp1, tmp2;
mp_set_from_integer(2, &tmp1);
mp_xpowy_integer(&tmp1, wordlen, &tmp2);
return mp_is_greater_than (&tmp2, x);
}
void
mp_and(const MPNumber *x, const MPNumber *y, MPNumber *z)
{
if (!mp_is_positive_integer(x) || !mp_is_positive_integer(y))
{
/* Translators: Error displayed when boolean AND attempted on non-integer values */
mperr(_("Boolean AND is only defined for positive integers"));
}
mp_bitwise(x, y, mp_bitwise_and, z, 0);
}
void
mp_or(const MPNumber *x, const MPNumber *y, MPNumber *z)
{
if (!mp_is_positive_integer(x) || !mp_is_positive_integer(y))
{
/* Translators: Error displayed when boolean OR attempted on non-integer values */
mperr(_("Boolean OR is only defined for positive integers"));
}
mp_bitwise(x, y, mp_bitwise_or, z, 0);
}
void
mp_xor(const MPNumber *x, const MPNumber *y, MPNumber *z)
{
if (!mp_is_positive_integer(x) || !mp_is_positive_integer(y))
{
/* Translators: Error displayed when boolean XOR attempted on non-integer values */
mperr(_("Boolean XOR is only defined for positive integers"));
}
mp_bitwise(x, y, mp_bitwise_xor, z, 0);
}
void
mp_not(const MPNumber *x, int wordlen, MPNumber *z)
{
MPNumber temp;
if (!mp_is_positive_integer(x))
{
/* Translators: Error displayed when boolean XOR attempted on non-integer values */
mperr(_("Boolean NOT is only defined for positive integers"));
}
mp_set_from_integer(0, &temp);
mp_bitwise(x, &temp, mp_bitwise_not, z, wordlen);
}
void
mp_mask(const MPNumber *x, int wordlen, MPNumber *z)
{
char *text;
size_t len, offset;
/* Convert to a hexadecimal string and use last characters */
text = to_hex_string(x);
len = strlen(text);
offset = wordlen / 4;
offset = len > offset ? len - offset: 0;
mp_set_from_string(text + offset, 16, z);
g_free(text);
}
void
mp_shift(const MPNumber *x, int count, MPNumber *z)
{
int i;
MPNumber multiplier;
mp_set_from_integer(1, &multiplier);
if (!mp_is_integer(x)) {
/* Translators: Error displayed when bit shift attempted on non-integer values */
mperr(_("Shift is only possible on integer values"));
return;
}
if (count >= 0) {
for (i = 0; i < count; i++)
mp_multiply_integer(&multiplier, 2, &multiplier);
mp_multiply(x, &multiplier, z);
}
else {
for (i = 0; i < -count; i++)
mp_multiply_integer(&multiplier, 2, &multiplier);
mp_divide(x, &multiplier, z);
mp_floor(z, z);
}
}
void
mp_ones_complement(const MPNumber *x, int wordlen, MPNumber *z)
{
MPNumber t;
mp_set_from_integer(0, &t);
mp_bitwise(x, &t, mp_bitwise_xor, z, wordlen);
mp_not(z, wordlen, z);
}
void
mp_twos_complement(const MPNumber *x, int wordlen, MPNumber *z)
{
mp_ones_complement (x, wordlen, z);
mp_add_integer (z, 1, z);
}
|
