ce188d4d |
1 | /* libFLAC - Free Lossless Audio Codec library |
2 | * Copyright (C) 2000-2009 Josh Coalson |
3 | * Copyright (C) 2011-2016 Xiph.Org Foundation |
4 | * |
5 | * Redistribution and use in source and binary forms, with or without |
6 | * modification, are permitted provided that the following conditions |
7 | * are met: |
8 | * |
9 | * - Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
11 | * |
12 | * - Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * |
16 | * - Neither the name of the Xiph.org Foundation nor the names of its |
17 | * contributors may be used to endorse or promote products derived from |
18 | * this software without specific prior written permission. |
19 | * |
20 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
21 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
22 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
23 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR |
24 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
25 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
26 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
27 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
28 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
29 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
30 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
31 | */ |
32 | |
33 | #ifndef FLAC__PRIVATE__CRC_H |
34 | #define FLAC__PRIVATE__CRC_H |
35 | |
36 | #include "FLAC/ordinals.h" |
37 | |
38 | /* 8 bit CRC generator, MSB shifted first |
39 | ** polynomial = x^8 + x^2 + x^1 + x^0 |
40 | ** init = 0 |
41 | */ |
42 | extern FLAC__byte const FLAC__crc8_table[256]; |
43 | #define FLAC__CRC8_UPDATE(data, crc) (crc) = FLAC__crc8_table[(crc) ^ (data)]; |
44 | void FLAC__crc8_update(const FLAC__byte data, FLAC__uint8 *crc); |
45 | void FLAC__crc8_update_block(const FLAC__byte *data, unsigned len, FLAC__uint8 *crc); |
46 | FLAC__uint8 FLAC__crc8(const FLAC__byte *data, unsigned len); |
47 | |
48 | /* 16 bit CRC generator, MSB shifted first |
49 | ** polynomial = x^16 + x^15 + x^2 + x^0 |
50 | ** init = 0 |
51 | */ |
52 | extern unsigned const FLAC__crc16_table[256]; |
53 | |
54 | #define FLAC__CRC16_UPDATE(data, crc) ((((crc)<<8) & 0xffff) ^ FLAC__crc16_table[((crc)>>8) ^ (data)]) |
55 | /* this alternate may be faster on some systems/compilers */ |
56 | #if 0 |
57 | #define FLAC__CRC16_UPDATE(data, crc) ((((crc)<<8) ^ FLAC__crc16_table[((crc)>>8) ^ (data)]) & 0xffff) |
58 | #endif |
59 | |
60 | unsigned FLAC__crc16(const FLAC__byte *data, unsigned len); |
61 | |
62 | #endif |