xref: /aosp_15_r20/external/flac/src/libFLAC/include/private/crc.h (revision 600f14f40d737144c998e2ec7a483122d3776fbc)
1*600f14f4SXin Li /* libFLAC - Free Lossless Audio Codec library
2*600f14f4SXin Li  * Copyright (C) 2000-2009  Josh Coalson
3*600f14f4SXin Li  * Copyright (C) 2011-2023  Xiph.Org Foundation
4*600f14f4SXin Li  *
5*600f14f4SXin Li  * Redistribution and use in source and binary forms, with or without
6*600f14f4SXin Li  * modification, are permitted provided that the following conditions
7*600f14f4SXin Li  * are met:
8*600f14f4SXin Li  *
9*600f14f4SXin Li  * - Redistributions of source code must retain the above copyright
10*600f14f4SXin Li  * notice, this list of conditions and the following disclaimer.
11*600f14f4SXin Li  *
12*600f14f4SXin Li  * - Redistributions in binary form must reproduce the above copyright
13*600f14f4SXin Li  * notice, this list of conditions and the following disclaimer in the
14*600f14f4SXin Li  * documentation and/or other materials provided with the distribution.
15*600f14f4SXin Li  *
16*600f14f4SXin Li  * - Neither the name of the Xiph.org Foundation nor the names of its
17*600f14f4SXin Li  * contributors may be used to endorse or promote products derived from
18*600f14f4SXin Li  * this software without specific prior written permission.
19*600f14f4SXin Li  *
20*600f14f4SXin Li  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21*600f14f4SXin Li  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22*600f14f4SXin Li  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23*600f14f4SXin Li  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
24*600f14f4SXin Li  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25*600f14f4SXin Li  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26*600f14f4SXin Li  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27*600f14f4SXin Li  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28*600f14f4SXin Li  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29*600f14f4SXin Li  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30*600f14f4SXin Li  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31*600f14f4SXin Li  */
32*600f14f4SXin Li 
33*600f14f4SXin Li #ifndef FLAC__PRIVATE__CRC_H
34*600f14f4SXin Li #define FLAC__PRIVATE__CRC_H
35*600f14f4SXin Li 
36*600f14f4SXin Li #include "FLAC/ordinals.h"
37*600f14f4SXin Li 
38*600f14f4SXin Li /* 8 bit CRC generator, MSB shifted first
39*600f14f4SXin Li ** polynomial = x^8 + x^2 + x^1 + x^0
40*600f14f4SXin Li ** init = 0
41*600f14f4SXin Li */
42*600f14f4SXin Li FLAC__uint8 FLAC__crc8(const FLAC__byte *data, uint32_t len);
43*600f14f4SXin Li 
44*600f14f4SXin Li /* 16 bit CRC generator, MSB shifted first
45*600f14f4SXin Li ** polynomial = x^16 + x^15 + x^2 + x^0
46*600f14f4SXin Li ** init = 0
47*600f14f4SXin Li */
48*600f14f4SXin Li extern FLAC__uint16 const FLAC__crc16_table[8][256];
49*600f14f4SXin Li 
50*600f14f4SXin Li #define FLAC__CRC16_UPDATE(data, crc) ((((crc)<<8) & 0xffff) ^ FLAC__crc16_table[0][((crc)>>8) ^ (data)])
51*600f14f4SXin Li /* this alternate may be faster on some systems/compilers */
52*600f14f4SXin Li #if 0
53*600f14f4SXin Li #define FLAC__CRC16_UPDATE(data, crc) ((((crc)<<8) ^ FLAC__crc16_table[0][((crc)>>8) ^ (data)]) & 0xffff)
54*600f14f4SXin Li #endif
55*600f14f4SXin Li 
56*600f14f4SXin Li FLAC__uint16 FLAC__crc16(const FLAC__byte *data, uint32_t len);
57*600f14f4SXin Li FLAC__uint16 FLAC__crc16_update_words32(const FLAC__uint32 *words, uint32_t len, FLAC__uint16 crc);
58*600f14f4SXin Li FLAC__uint16 FLAC__crc16_update_words64(const FLAC__uint64 *words, uint32_t len, FLAC__uint16 crc);
59*600f14f4SXin Li 
60*600f14f4SXin Li #endif
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