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
|
/*********************************************************************
* *
* Library : lib_crc *
* File : lib_crc.c *
* Author : Lammert Bies 1999-2008 *
* E-mail : info@lammertbies.nl *
* Language : ANSI C *
* *
* *
* Description *
* =========== *
* *
* The file lib_crc.c contains the private and public func- *
* tions used for the calculation of CRC-16, CRC-CCITT and *
* CRC-32 cyclic redundancy values. *
* *
* *
* Dependencies *
* ============ *
* *
* libcrc.h CRC definitions and prototypes *
* *
********************************************************************/
#include <stdint.h>
#ifndef G_GUINT64_CONSTANT
#define G_GUINT64_CONSTANT(val) (val##UL)
#endif
void *crc_table;
/* private */
void init_crc8_normal_tab(uint8_t polynom)
{
int i, j;
uint8_t crc;
uint8_t *p;
p = (uint8_t *) crc_table;
for (i=0; i<256; i++)
{
crc = (uint8_t) i;
for (j=0; j<8; j++)
{
if (crc & 0x80) crc = (crc << 1) ^ polynom;
else crc <<= 1;
}
*p++ = crc;
}
}
void init_crc8_reflected_tab(uint8_t polynom)
{
int i, j;
uint8_t crc;
uint8_t *p;
p = (uint8_t *) crc_table;
for (i=0; i<256; i++)
{
crc = (uint8_t) i;
for (j=0; j<8; j++)
{
if (crc & 0x01) crc = (crc >> 1) ^ polynom;
else crc >>= 1;
}
*p++ = crc;
}
}
/* Common routines for calculations */
void init_crc16_normal_tab(uint16_t polynom)
{
int i, j;
uint16_t crc;
uint16_t *p;
p = (uint16_t *) crc_table;
for (i=0; i<256; i++)
{
crc = ((uint16_t) i) << 8;
for (j=0; j<8; j++)
{
if ( crc & 0x8000 ) crc = ( crc << 1 ) ^ polynom;
else crc <<= 1;
}
*p++ = crc;
}
}
void init_crc16_reflected_tab(uint16_t polynom)
{
int i, j;
uint16_t crc;
uint16_t *p;
p = (uint16_t *) crc_table;
for (i=0; i<256; i++)
{
crc = (uint16_t) i;
for (j=0; j<8; j++)
{
if ( crc & 0x0001 ) crc = ( crc >> 1 ) ^ polynom;
else crc >>= 1;
}
*p++ = crc;
}
}
void init_crc32_normal_tab(uint32_t polynom)
{
int i, j;
uint32_t crc;
uint32_t *p;
p = (uint32_t *) crc_table;
for (i=0; i<256; i++)
{
crc = ((uint32_t) i) << 24;
for (j=0; j<8; j++)
{
if ( crc & 0x80000000L ) crc = ( crc << 1 ) ^ polynom;
else crc <<= 1;
}
*p++ = crc;
}
}
void init_crc32_reflected_tab(uint32_t polynom)
{
int i, j;
uint32_t crc;
uint32_t *p;
p = (uint32_t *) crc_table;
for (i=0; i<256; i++)
{
crc = (uint32_t) i;
for (j=0; j<8; j++)
{
if ( crc & 0x00000001L ) crc = ( crc >> 1 ) ^ polynom;
else crc >>= 1;
}
*p++ = crc;
}
}
/* Common routines for calculations */
uint8_t update_crc8(uint8_t crc, uint8_t c)
{
return (((uint8_t *) crc_table)[crc ^ c]);
}
uint16_t update_crc16_normal(uint16_t crc, char c )
{
uint16_t short_c;
short_c = 0x00ff & (uint16_t) c;
/* Normal form */
return (crc << 8) ^ ((uint16_t *) crc_table)[(crc >> 8) ^ short_c];
}
uint16_t update_crc16_reflected(uint16_t crc, char c )
{
uint16_t short_c;
short_c = 0x00ff & (uint16_t) c;
/* Reflected form */
return (crc >> 8) ^ ((uint16_t *) crc_table)[(crc ^ short_c) & 0xff];
}
uint32_t update_crc32_normal(uint32_t crc, char c )
{
uint32_t long_c;
long_c = 0x000000ffL & (uint32_t) c;
return (crc << 8) ^ ((uint32_t *) crc_table)[((crc >> 24) ^ long_c) & 0xff];
}
uint32_t update_crc32_reflected(uint32_t crc, char c )
{
uint32_t long_c;
long_c = 0x000000ffL & (uint32_t) c;
return (crc >> 8) ^ ((uint32_t *) crc_table)[(crc ^ long_c) & 0xff];
}
|
