]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | #include <stdio.h> |
2 | #include "crc32defs.h" | |
3 | #include <inttypes.h> | |
4 | ||
5 | #define ENTRIES_PER_LINE 4 | |
6 | ||
9a1dbf6a | 7 | #if CRC_LE_BITS <= 8 |
1da177e4 | 8 | #define LE_TABLE_SIZE (1 << CRC_LE_BITS) |
9a1dbf6a BP |
9 | #else |
10 | #define LE_TABLE_SIZE 256 | |
11 | #endif | |
12 | ||
13 | #if CRC_BE_BITS <= 8 | |
1da177e4 | 14 | #define BE_TABLE_SIZE (1 << CRC_BE_BITS) |
9a1dbf6a BP |
15 | #else |
16 | #define BE_TABLE_SIZE 256 | |
17 | #endif | |
1da177e4 | 18 | |
60e58d5c BP |
19 | static uint32_t crc32table_le[4][256]; |
20 | static uint32_t crc32table_be[4][256]; | |
1da177e4 LT |
21 | |
22 | /** | |
23 | * crc32init_le() - allocate and initialize LE table data | |
24 | * | |
25 | * crc is the crc of the byte i; other entries are filled in based on the | |
26 | * fact that crctable[i^j] = crctable[i] ^ crctable[j]. | |
27 | * | |
28 | */ | |
29 | static void crc32init_le(void) | |
30 | { | |
31 | unsigned i, j; | |
32 | uint32_t crc = 1; | |
33 | ||
836e2af9 | 34 | crc32table_le[0][0] = 0; |
1da177e4 | 35 | |
9a1dbf6a | 36 | for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) { |
1da177e4 LT |
37 | crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); |
38 | for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) | |
836e2af9 JT |
39 | crc32table_le[0][i + j] = crc ^ crc32table_le[0][j]; |
40 | } | |
41 | for (i = 0; i < LE_TABLE_SIZE; i++) { | |
42 | crc = crc32table_le[0][i]; | |
43 | for (j = 1; j < 4; j++) { | |
44 | crc = crc32table_le[0][crc & 0xff] ^ (crc >> 8); | |
45 | crc32table_le[j][i] = crc; | |
46 | } | |
1da177e4 LT |
47 | } |
48 | } | |
49 | ||
50 | /** | |
51 | * crc32init_be() - allocate and initialize BE table data | |
52 | */ | |
53 | static void crc32init_be(void) | |
54 | { | |
55 | unsigned i, j; | |
56 | uint32_t crc = 0x80000000; | |
57 | ||
836e2af9 | 58 | crc32table_be[0][0] = 0; |
1da177e4 LT |
59 | |
60 | for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { | |
61 | crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0); | |
62 | for (j = 0; j < i; j++) | |
836e2af9 JT |
63 | crc32table_be[0][i + j] = crc ^ crc32table_be[0][j]; |
64 | } | |
65 | for (i = 0; i < BE_TABLE_SIZE; i++) { | |
66 | crc = crc32table_be[0][i]; | |
67 | for (j = 1; j < 4; j++) { | |
68 | crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8); | |
69 | crc32table_be[j][i] = crc; | |
70 | } | |
1da177e4 LT |
71 | } |
72 | } | |
73 | ||
60e58d5c | 74 | static void output_table(uint32_t (*table)[256], int len, char *trans) |
1da177e4 | 75 | { |
836e2af9 | 76 | int i, j; |
1da177e4 | 77 | |
836e2af9 JT |
78 | for (j = 0 ; j < 4; j++) { |
79 | printf("{"); | |
80 | for (i = 0; i < len - 1; i++) { | |
81 | if (i % ENTRIES_PER_LINE == 0) | |
82 | printf("\n"); | |
83 | printf("%s(0x%8.8xL), ", trans, table[j][i]); | |
84 | } | |
85 | printf("%s(0x%8.8xL)},\n", trans, table[j][len - 1]); | |
1da177e4 | 86 | } |
1da177e4 LT |
87 | } |
88 | ||
89 | int main(int argc, char** argv) | |
90 | { | |
91 | printf("/* this file is generated - do not edit */\n\n"); | |
92 | ||
93 | if (CRC_LE_BITS > 1) { | |
94 | crc32init_le(); | |
836e2af9 | 95 | printf("static const u32 crc32table_le[4][256] = {"); |
1da177e4 LT |
96 | output_table(crc32table_le, LE_TABLE_SIZE, "tole"); |
97 | printf("};\n"); | |
98 | } | |
99 | ||
100 | if (CRC_BE_BITS > 1) { | |
101 | crc32init_be(); | |
836e2af9 | 102 | printf("static const u32 crc32table_be[4][256] = {"); |
1da177e4 LT |
103 | output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); |
104 | printf("};\n"); | |
105 | } | |
106 | ||
107 | return 0; | |
108 | } |