| /* |
| * Copyright (c) Yann Collet, Facebook, Inc. |
| * All rights reserved. |
| * |
| * This source code is licensed under both the BSD-style license (found in the |
| * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| * in the COPYING file in the root directory of this source tree). |
| * You may select, at your option, one of the above-listed licenses. |
| */ |
| |
| /* zstd_decompress_internal: |
| * objects and definitions shared within lib/decompress modules */ |
| |
| #ifndef ZSTD_DECOMPRESS_INTERNAL_H |
| #define ZSTD_DECOMPRESS_INTERNAL_H |
| |
| /*-******************************************************* |
| * Dependencies |
| *********************************************************/ |
| #include "../common/mem.h" /* BYTE, U16, U32 */ |
| #include "../common/zstd_internal.h" /* constants : MaxLL, MaxML, MaxOff, LLFSELog, etc. */ |
| |
| /*-******************************************************* |
| * Constants |
| *********************************************************/ |
| static UNUSED_ATTR const U32 LL_base[MaxLL+1] = { |
| 0, 1, 2, 3, 4, 5, 6, 7, |
| 8, 9, 10, 11, 12, 13, 14, 15, |
| 16, 18, 20, 22, 24, 28, 32, 40, |
| 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, |
| 0x2000, 0x4000, 0x8000, 0x10000 }; |
| |
| static UNUSED_ATTR const U32 OF_base[MaxOff+1] = { |
| 0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, |
| 0xFD, 0x1FD, 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, |
| 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, |
| 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD, 0x1FFFFFFD, 0x3FFFFFFD, 0x7FFFFFFD }; |
| |
| static UNUSED_ATTR const U8 OF_bits[MaxOff+1] = { |
| 0, 1, 2, 3, 4, 5, 6, 7, |
| 8, 9, 10, 11, 12, 13, 14, 15, |
| 16, 17, 18, 19, 20, 21, 22, 23, |
| 24, 25, 26, 27, 28, 29, 30, 31 }; |
| |
| static UNUSED_ATTR const U32 ML_base[MaxML+1] = { |
| 3, 4, 5, 6, 7, 8, 9, 10, |
| 11, 12, 13, 14, 15, 16, 17, 18, |
| 19, 20, 21, 22, 23, 24, 25, 26, |
| 27, 28, 29, 30, 31, 32, 33, 34, |
| 35, 37, 39, 41, 43, 47, 51, 59, |
| 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, |
| 0x1003, 0x2003, 0x4003, 0x8003, 0x10003 }; |
| |
| /*-******************************************************* |
| * Decompression types |
| *********************************************************/ |
| typedef struct { |
| U32 fastMode; |
| U32 tableLog; |
| } ZSTD_seqSymbol_header; |
| |
| typedef struct { |
| U16 nextState; |
| BYTE nbAdditionalBits; |
| BYTE nbBits; |
| U32 baseValue; |
| } ZSTD_seqSymbol; |
| |
| #define SEQSYMBOL_TABLE_SIZE(log) (1 + (1 << (log))) |
| |
| #define ZSTD_BUILD_FSE_TABLE_WKSP_SIZE (sizeof(S16) * (MaxSeq + 1) + (1u << MaxFSELog) + sizeof(U64)) |
| #define ZSTD_BUILD_FSE_TABLE_WKSP_SIZE_U32 ((ZSTD_BUILD_FSE_TABLE_WKSP_SIZE + sizeof(U32) - 1) / sizeof(U32)) |
| |
| typedef struct { |
| ZSTD_seqSymbol LLTable[SEQSYMBOL_TABLE_SIZE(LLFSELog)]; /* Note : Space reserved for FSE Tables */ |
| ZSTD_seqSymbol OFTable[SEQSYMBOL_TABLE_SIZE(OffFSELog)]; /* is also used as temporary workspace while building hufTable during DDict creation */ |
| ZSTD_seqSymbol MLTable[SEQSYMBOL_TABLE_SIZE(MLFSELog)]; /* and therefore must be at least HUF_DECOMPRESS_WORKSPACE_SIZE large */ |
| HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */ |
| U32 rep[ZSTD_REP_NUM]; |
| U32 workspace[ZSTD_BUILD_FSE_TABLE_WKSP_SIZE_U32]; |
| } ZSTD_entropyDTables_t; |
| |
| typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader, |
| ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock, |
| ZSTDds_decompressLastBlock, ZSTDds_checkChecksum, |
| ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } ZSTD_dStage; |
| |
| typedef enum { zdss_init=0, zdss_loadHeader, |
| zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage; |
| |
| typedef enum { |
| ZSTD_use_indefinitely = -1, /* Use the dictionary indefinitely */ |
| ZSTD_dont_use = 0, /* Do not use the dictionary (if one exists free it) */ |
| ZSTD_use_once = 1 /* Use the dictionary once and set to ZSTD_dont_use */ |
| } ZSTD_dictUses_e; |
| |
| /* Hashset for storing references to multiple ZSTD_DDict within ZSTD_DCtx */ |
| typedef struct { |
| const ZSTD_DDict** ddictPtrTable; |
| size_t ddictPtrTableSize; |
| size_t ddictPtrCount; |
| } ZSTD_DDictHashSet; |
| |
| #ifndef ZSTD_DECODER_INTERNAL_BUFFER |
| # define ZSTD_DECODER_INTERNAL_BUFFER (1 << 16) |
| #endif |
| |
| #define ZSTD_LBMIN 64 |
| #define ZSTD_LBMAX (128 << 10) |
| |
| /* extra buffer, compensates when dst is not large enough to store litBuffer */ |
| #define ZSTD_LITBUFFEREXTRASIZE BOUNDED(ZSTD_LBMIN, ZSTD_DECODER_INTERNAL_BUFFER, ZSTD_LBMAX) |
| |
| typedef enum { |
| ZSTD_not_in_dst = 0, /* Stored entirely within litExtraBuffer */ |
| ZSTD_in_dst = 1, /* Stored entirely within dst (in memory after current output write) */ |
| ZSTD_split = 2 /* Split between litExtraBuffer and dst */ |
| } ZSTD_litLocation_e; |
| |
| struct ZSTD_DCtx_s |
| { |
| const ZSTD_seqSymbol* LLTptr; |
| const ZSTD_seqSymbol* MLTptr; |
| const ZSTD_seqSymbol* OFTptr; |
| const HUF_DTable* HUFptr; |
| ZSTD_entropyDTables_t entropy; |
| U32 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32]; /* space needed when building huffman tables */ |
| const void* previousDstEnd; /* detect continuity */ |
| const void* prefixStart; /* start of current segment */ |
| const void* virtualStart; /* virtual start of previous segment if it was just before current one */ |
| const void* dictEnd; /* end of previous segment */ |
| size_t expected; |
| ZSTD_frameHeader fParams; |
| U64 processedCSize; |
| U64 decodedSize; |
| blockType_e bType; /* used in ZSTD_decompressContinue(), store blockType between block header decoding and block decompression stages */ |
| ZSTD_dStage stage; |
| U32 litEntropy; |
| U32 fseEntropy; |
| struct xxh64_state xxhState; |
| size_t headerSize; |
| ZSTD_format_e format; |
| ZSTD_forceIgnoreChecksum_e forceIgnoreChecksum; /* User specified: if == 1, will ignore checksums in compressed frame. Default == 0 */ |
| U32 validateChecksum; /* if == 1, will validate checksum. Is == 1 if (fParams.checksumFlag == 1) and (forceIgnoreChecksum == 0). */ |
| const BYTE* litPtr; |
| ZSTD_customMem customMem; |
| size_t litSize; |
| size_t rleSize; |
| size_t staticSize; |
| #if DYNAMIC_BMI2 != 0 |
| int bmi2; /* == 1 if the CPU supports BMI2 and 0 otherwise. CPU support is determined dynamically once per context lifetime. */ |
| #endif |
| |
| /* dictionary */ |
| ZSTD_DDict* ddictLocal; |
| const ZSTD_DDict* ddict; /* set by ZSTD_initDStream_usingDDict(), or ZSTD_DCtx_refDDict() */ |
| U32 dictID; |
| int ddictIsCold; /* if == 1 : dictionary is "new" for working context, and presumed "cold" (not in cpu cache) */ |
| ZSTD_dictUses_e dictUses; |
| ZSTD_DDictHashSet* ddictSet; /* Hash set for multiple ddicts */ |
| ZSTD_refMultipleDDicts_e refMultipleDDicts; /* User specified: if == 1, will allow references to multiple DDicts. Default == 0 (disabled) */ |
| |
| /* streaming */ |
| ZSTD_dStreamStage streamStage; |
| char* inBuff; |
| size_t inBuffSize; |
| size_t inPos; |
| size_t maxWindowSize; |
| char* outBuff; |
| size_t outBuffSize; |
| size_t outStart; |
| size_t outEnd; |
| size_t lhSize; |
| U32 hostageByte; |
| int noForwardProgress; |
| ZSTD_bufferMode_e outBufferMode; |
| ZSTD_outBuffer expectedOutBuffer; |
| |
| /* workspace */ |
| BYTE* litBuffer; |
| const BYTE* litBufferEnd; |
| ZSTD_litLocation_e litBufferLocation; |
| BYTE litExtraBuffer[ZSTD_LITBUFFEREXTRASIZE + WILDCOPY_OVERLENGTH]; /* literal buffer can be split between storage within dst and within this scratch buffer */ |
| BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; |
| |
| size_t oversizedDuration; |
| |
| #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION |
| void const* dictContentBeginForFuzzing; |
| void const* dictContentEndForFuzzing; |
| #endif |
| |
| /* Tracing */ |
| }; /* typedef'd to ZSTD_DCtx within "zstd.h" */ |
| |
| MEM_STATIC int ZSTD_DCtx_get_bmi2(const struct ZSTD_DCtx_s *dctx) { |
| #if DYNAMIC_BMI2 != 0 |
| return dctx->bmi2; |
| #else |
| (void)dctx; |
| return 0; |
| #endif |
| } |
| |
| /*-******************************************************* |
| * Shared internal functions |
| *********************************************************/ |
| |
| /*! ZSTD_loadDEntropy() : |
| * dict : must point at beginning of a valid zstd dictionary. |
| * @return : size of dictionary header (size of magic number + dict ID + entropy tables) */ |
| size_t ZSTD_loadDEntropy(ZSTD_entropyDTables_t* entropy, |
| const void* const dict, size_t const dictSize); |
| |
| /*! ZSTD_checkContinuity() : |
| * check if next `dst` follows previous position, where decompression ended. |
| * If yes, do nothing (continue on current segment). |
| * If not, classify previous segment as "external dictionary", and start a new segment. |
| * This function cannot fail. */ |
| void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst, size_t dstSize); |
| |
| #endif /* ZSTD_DECOMPRESS_INTERNAL_H */ |