1 /* SPDX-License-Identifier: (GPL-2.0 or BSD-2-Clause) */ 2 /* 3 * Huffman coder, part of New Generation Entropy library 4 * header file 5 * Copyright (C) 2013-2016, Yann Collet. 6 * 7 * You can contact the author at : 8 * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy 9 */ 10 #ifndef HUF_H_298734234 11 #define HUF_H_298734234 12 13 /* *** Dependencies *** */ 14 #include <linux/types.h> /* size_t */ 15 16 /* *** Tool functions *** */ 17 #define HUF_BLOCKSIZE_MAX (128 * 1024) /**< maximum input size for a single block compressed with HUF_compress */ 18 size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */ 19 20 /* Error Management */ 21 unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */ 22 23 /* *** Advanced function *** */ 24 25 /** HUF_compress4X_wksp() : 26 * Same as HUF_compress2(), but uses externally allocated `workSpace`, which must be a table of >= 1024 unsigned */ 27 size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, 28 size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ 29 30 /* *** Dependencies *** */ 31 #include "mem.h" /* U32 */ 32 33 /* *** Constants *** */ 34 #define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */ 35 #define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */ 36 #define HUF_SYMBOLVALUE_MAX 255 37 38 #define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ 39 #if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX) 40 #error "HUF_TABLELOG_MAX is too large !" 41 #endif 42 43 /* **************************************** 44 * Static allocation 45 ******************************************/ 46 /* HUF buffer bounds */ 47 #define HUF_CTABLEBOUND 129 48 #define HUF_BLOCKBOUND(size) (size + (size >> 8) + 8) /* only true if incompressible pre-filtered with fast heuristic */ 49 #define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ 50 51 /* static allocation of HUF's Compression Table */ 52 #define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \ 53 U32 name##hb[maxSymbolValue + 1]; \ 54 void *name##hv = &(name##hb); \ 55 HUF_CElt *name = (HUF_CElt *)(name##hv) /* no final ; */ 56 57 /* static allocation of HUF's DTable */ 58 typedef U32 HUF_DTable; 59 #define HUF_DTABLE_SIZE(maxTableLog) (1 + (1 << (maxTableLog))) 60 #define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = {((U32)((maxTableLog)-1) * 0x01000001)} 61 #define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = {((U32)(maxTableLog)*0x01000001)} 62 63 /* The workspace must have alignment at least 4 and be at least this large */ 64 #define HUF_COMPRESS_WORKSPACE_SIZE (6 << 10) 65 #define HUF_COMPRESS_WORKSPACE_SIZE_U32 (HUF_COMPRESS_WORKSPACE_SIZE / sizeof(U32)) 66 67 /* The workspace must have alignment at least 4 and be at least this large */ 68 #define HUF_DECOMPRESS_WORKSPACE_SIZE (3 << 10) 69 #define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32)) 70 71 /* **************************************** 72 * Advanced decompression functions 73 ******************************************/ 74 size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); /**< decodes RLE and uncompressed */ 75 size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, 76 size_t workspaceSize); /**< considers RLE and uncompressed as errors */ 77 size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, 78 size_t workspaceSize); /**< single-symbol decoder */ 79 size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, 80 size_t workspaceSize); /**< double-symbols decoder */ 81 82 /* **************************************** 83 * HUF detailed API 84 ******************************************/ 85 /*! 86 HUF_compress() does the following: 87 1. count symbol occurrence from source[] into table count[] using FSE_count() 88 2. (optional) refine tableLog using HUF_optimalTableLog() 89 3. build Huffman table from count using HUF_buildCTable() 90 4. save Huffman table to memory buffer using HUF_writeCTable_wksp() 91 5. encode the data stream using HUF_compress4X_usingCTable() 92 93 The following API allows targeting specific sub-functions for advanced tasks. 94 For example, it's possible to compress several blocks using the same 'CTable', 95 or to save and regenerate 'CTable' using external methods. 96 */ 97 /* FSE_count() : find it within "fse.h" */ 98 unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue); 99 typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */ 100 size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, unsigned maxSymbolValue, unsigned huffLog, void *workspace, size_t workspaceSize); 101 size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); 102 103 typedef enum { 104 HUF_repeat_none, /**< Cannot use the previous table */ 105 HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, 106 4}X_repeat */ 107 HUF_repeat_valid /**< Can use the previous table and it is asumed to be valid */ 108 } HUF_repeat; 109 /** HUF_compress4X_repeat() : 110 * Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. 111 * If it uses hufTable it does not modify hufTable or repeat. 112 * If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. 113 * If preferRepeat then the old table will always be used if valid. */ 114 size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, 115 size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, 116 int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ 117 118 /** HUF_buildCTable_wksp() : 119 * Same as HUF_buildCTable(), but using externally allocated scratch buffer. 120 * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned. 121 */ 122 size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize); 123 124 /*! HUF_readStats() : 125 Read compact Huffman tree, saved by HUF_writeCTable(). 126 `huffWeight` is destination buffer. 127 @return : size read from `src` , or an error Code . 128 Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */ 129 size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, 130 void *workspace, size_t workspaceSize); 131 132 /** HUF_readCTable() : 133 * Loading a CTable saved with HUF_writeCTable() */ 134 size_t HUF_readCTable_wksp(HUF_CElt *CTable, unsigned maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); 135 136 /* 137 HUF_decompress() does the following: 138 1. select the decompression algorithm (X2, X4) based on pre-computed heuristics 139 2. build Huffman table from save, using HUF_readDTableXn() 140 3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable 141 */ 142 143 /** HUF_selectDecoder() : 144 * Tells which decoder is likely to decode faster, 145 * based on a set of pre-determined metrics. 146 * @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . 147 * Assumption : 0 < cSrcSize < dstSize <= 128 KB */ 148 U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize); 149 150 size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); 151 size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); 152 153 size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); 154 size_t HUF_decompress4X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); 155 size_t HUF_decompress4X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); 156 157 /* single stream variants */ 158 159 size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, 160 size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ 161 size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); 162 /** HUF_compress1X_repeat() : 163 * Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. 164 * If it uses hufTable it does not modify hufTable or repeat. 165 * If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. 166 * If preferRepeat then the old table will always be used if valid. */ 167 size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, 168 size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, 169 int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ 170 171 size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); 172 size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, 173 size_t workspaceSize); /**< single-symbol decoder */ 174 size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, 175 size_t workspaceSize); /**< double-symbols decoder */ 176 177 size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, 178 const HUF_DTable *DTable); /**< automatic selection of sing or double symbol decoder, based on DTable */ 179 size_t HUF_decompress1X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); 180 size_t HUF_decompress1X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); 181 182 #endif /* HUF_H_298734234 */ 183