xref: /linux/lib/zstd/decompress/zstd_decompress_block.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /*
2  * Copyright (c) Yann Collet, Facebook, Inc.
3  * All rights reserved.
4  *
5  * This source code is licensed under both the BSD-style license (found in the
6  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7  * in the COPYING file in the root directory of this source tree).
8  * You may select, at your option, one of the above-listed licenses.
9  */
10 
11 
12 #ifndef ZSTD_DEC_BLOCK_H
13 #define ZSTD_DEC_BLOCK_H
14 
15 /*-*******************************************************
16  *  Dependencies
17  *********************************************************/
18 #include "../common/zstd_deps.h"   /* size_t */
19 #include <linux/zstd.h>    /* DCtx, and some public functions */
20 #include "../common/zstd_internal.h"  /* blockProperties_t, and some public functions */
21 #include "zstd_decompress_internal.h"  /* ZSTD_seqSymbol */
22 
23 
24 /* ===   Prototypes   === */
25 
26 /* note: prototypes already published within `zstd.h` :
27  * ZSTD_decompressBlock()
28  */
29 
30 /* note: prototypes already published within `zstd_internal.h` :
31  * ZSTD_getcBlockSize()
32  * ZSTD_decodeSeqHeaders()
33  */
34 
35 
36  /* Streaming state is used to inform allocation of the literal buffer */
37 typedef enum {
38     not_streaming = 0,
39     is_streaming = 1
40 } streaming_operation;
41 
42 /* ZSTD_decompressBlock_internal() :
43  * decompress block, starting at `src`,
44  * into destination buffer `dst`.
45  * @return : decompressed block size,
46  *           or an error code (which can be tested using ZSTD_isError())
47  */
48 size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
49                                void* dst, size_t dstCapacity,
50                          const void* src, size_t srcSize, const int frame, const streaming_operation streaming);
51 
52 /* ZSTD_buildFSETable() :
53  * generate FSE decoding table for one symbol (ll, ml or off)
54  * this function must be called with valid parameters only
55  * (dt is large enough, normalizedCounter distribution total is a power of 2, max is within range, etc.)
56  * in which case it cannot fail.
57  * The workspace must be 4-byte aligned and at least ZSTD_BUILD_FSE_TABLE_WKSP_SIZE bytes, which is
58  * defined in zstd_decompress_internal.h.
59  * Internal use only.
60  */
61 void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
62              const short* normalizedCounter, unsigned maxSymbolValue,
63              const U32* baseValue, const U8* nbAdditionalBits,
64                    unsigned tableLog, void* wksp, size_t wkspSize,
65                    int bmi2);
66 
67 
68 #endif /* ZSTD_DEC_BLOCK_H */
69