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- /*
- LZ4 HC - High Compression Mode of LZ4
- Copyright (C) 2011-2015, Yann Collet.
- BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are
- met:
- * Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above
- copyright notice, this list of conditions and the following disclaimer
- in the documentation and/or other materials provided with the
- distribution.
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- You can contact the author at :
- - LZ4 source repository : https://github.com/Cyan4973/lz4
- - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
- */
- /* *************************************
- * Tuning Parameter
- ***************************************/
- static const int LZ4HC_compressionLevel_default = 9;
- /*!
- * HEAPMODE :
- * Select how default compression function will allocate workplace memory,
- * in stack (0:fastest), or in heap (1:requires malloc()).
- * Since workplace is rather large, heap mode is recommended.
- */
- #define LZ4HC_HEAPMODE 0
- /* *************************************
- * Includes
- ***************************************/
- #include "lz4hc.h"
- /* *************************************
- * Local Compiler Options
- ***************************************/
- #if defined(__GNUC__)
- # pragma GCC diagnostic ignored "-Wunused-function"
- #endif
- #if defined (__clang__)
- # pragma clang diagnostic ignored "-Wunused-function"
- #endif
- /* *************************************
- * Common LZ4 definition
- ***************************************/
- #define LZ4_COMMONDEFS_ONLY
- #include "lz4.c"
- /* *************************************
- * Local Constants
- ***************************************/
- #define DICTIONARY_LOGSIZE 16
- #define MAXD (1<<DICTIONARY_LOGSIZE)
- #define MAXD_MASK (MAXD - 1)
- #define HASH_LOG (DICTIONARY_LOGSIZE-1)
- #define HASHTABLESIZE (1 << HASH_LOG)
- #define HASH_MASK (HASHTABLESIZE - 1)
- #define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH)
- static const int g_maxCompressionLevel = 16;
- /**************************************
- * Local Types
- **************************************/
- typedef struct
- {
- U32 hashTable[HASHTABLESIZE];
- U16 chainTable[MAXD];
- const BYTE* end; /* next block here to continue on current prefix */
- const BYTE* base; /* All index relative to this position */
- const BYTE* dictBase; /* alternate base for extDict */
- BYTE* inputBuffer; /* deprecated */
- U32 dictLimit; /* below that point, need extDict */
- U32 lowLimit; /* below that point, no more dict */
- U32 nextToUpdate; /* index from which to continue dictionary update */
- U32 compressionLevel;
- } LZ4HC_Data_Structure;
- /**************************************
- * Local Macros
- **************************************/
- #define HASH_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8)-HASH_LOG))
- //#define DELTANEXTU16(p) chainTable[(p) & MAXD_MASK] /* flexible, MAXD dependent */
- #define DELTANEXTU16(p) chainTable[(U16)(p)] /* faster */
- static U32 LZ4HC_hashPtr(const void* ptr) { return HASH_FUNCTION(LZ4_read32(ptr)); }
- /**************************************
- * HC Compression
- **************************************/
- static void LZ4HC_init (LZ4HC_Data_Structure* hc4, const BYTE* start)
- {
- MEM_INIT((void*)hc4->hashTable, 0, sizeof(hc4->hashTable));
- MEM_INIT(hc4->chainTable, 0xFF, sizeof(hc4->chainTable));
- hc4->nextToUpdate = 64 KB;
- hc4->base = start - 64 KB;
- hc4->end = start;
- hc4->dictBase = start - 64 KB;
- hc4->dictLimit = 64 KB;
- hc4->lowLimit = 64 KB;
- }
- /* Update chains up to ip (excluded) */
- FORCE_INLINE void LZ4HC_Insert (LZ4HC_Data_Structure* hc4, const BYTE* ip)
- {
- U16* chainTable = hc4->chainTable;
- U32* HashTable = hc4->hashTable;
- const BYTE* const base = hc4->base;
- const U32 target = (U32)(ip - base);
- U32 idx = hc4->nextToUpdate;
- while(idx < target)
- {
- U32 h = LZ4HC_hashPtr(base+idx);
- size_t delta = idx - HashTable[h];
- if (delta>MAX_DISTANCE) delta = MAX_DISTANCE;
- DELTANEXTU16(idx) = (U16)delta;
- HashTable[h] = idx;
- idx++;
- }
- hc4->nextToUpdate = target;
- }
- FORCE_INLINE int LZ4HC_InsertAndFindBestMatch (LZ4HC_Data_Structure* hc4, /* Index table will be updated */
- const BYTE* ip, const BYTE* const iLimit,
- const BYTE** matchpos,
- const int maxNbAttempts)
- {
- U16* const chainTable = hc4->chainTable;
- U32* const HashTable = hc4->hashTable;
- const BYTE* const base = hc4->base;
- const BYTE* const dictBase = hc4->dictBase;
- const U32 dictLimit = hc4->dictLimit;
- const U32 lowLimit = (hc4->lowLimit + 64 KB > (U32)(ip-base)) ? hc4->lowLimit : (U32)(ip - base) - (64 KB - 1);
- U32 matchIndex;
- const BYTE* match;
- int nbAttempts=maxNbAttempts;
- size_t ml=0;
- /* HC4 match finder */
- LZ4HC_Insert(hc4, ip);
- matchIndex = HashTable[LZ4HC_hashPtr(ip)];
- while ((matchIndex>=lowLimit) && (nbAttempts))
- {
- nbAttempts--;
- if (matchIndex >= dictLimit)
- {
- match = base + matchIndex;
- if (*(match+ml) == *(ip+ml)
- && (LZ4_read32(match) == LZ4_read32(ip)))
- {
- size_t mlt = LZ4_count(ip+MINMATCH, match+MINMATCH, iLimit) + MINMATCH;
- if (mlt > ml) { ml = mlt; *matchpos = match; }
- }
- }
- else
- {
- match = dictBase + matchIndex;
- if (LZ4_read32(match) == LZ4_read32(ip))
- {
- size_t mlt;
- const BYTE* vLimit = ip + (dictLimit - matchIndex);
- if (vLimit > iLimit) vLimit = iLimit;
- mlt = LZ4_count(ip+MINMATCH, match+MINMATCH, vLimit) + MINMATCH;
- if ((ip+mlt == vLimit) && (vLimit < iLimit))
- mlt += LZ4_count(ip+mlt, base+dictLimit, iLimit);
- if (mlt > ml) { ml = mlt; *matchpos = base + matchIndex; } /* virtual matchpos */
- }
- }
- matchIndex -= DELTANEXTU16(matchIndex);
- }
- return (int)ml;
- }
- FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch (
- LZ4HC_Data_Structure* hc4,
- const BYTE* const ip,
- const BYTE* const iLowLimit,
- const BYTE* const iHighLimit,
- int longest,
- const BYTE** matchpos,
- const BYTE** startpos,
- const int maxNbAttempts)
- {
- U16* const chainTable = hc4->chainTable;
- U32* const HashTable = hc4->hashTable;
- const BYTE* const base = hc4->base;
- const U32 dictLimit = hc4->dictLimit;
- const BYTE* const lowPrefixPtr = base + dictLimit;
- const U32 lowLimit = (hc4->lowLimit + 64 KB > (U32)(ip-base)) ? hc4->lowLimit : (U32)(ip - base) - (64 KB - 1);
- const BYTE* const dictBase = hc4->dictBase;
- U32 matchIndex;
- int nbAttempts = maxNbAttempts;
- int delta = (int)(ip-iLowLimit);
- /* First Match */
- LZ4HC_Insert(hc4, ip);
- matchIndex = HashTable[LZ4HC_hashPtr(ip)];
- while ((matchIndex>=lowLimit) && (nbAttempts))
- {
- nbAttempts--;
- if (matchIndex >= dictLimit)
- {
- const BYTE* matchPtr = base + matchIndex;
- if (*(iLowLimit + longest) == *(matchPtr - delta + longest))
- if (LZ4_read32(matchPtr) == LZ4_read32(ip))
- {
- int mlt = MINMATCH + LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, iHighLimit);
- int back = 0;
- while ((ip+back>iLowLimit)
- && (matchPtr+back > lowPrefixPtr)
- && (ip[back-1] == matchPtr[back-1]))
- back--;
- mlt -= back;
- if (mlt > longest)
- {
- longest = (int)mlt;
- *matchpos = matchPtr+back;
- *startpos = ip+back;
- }
- }
- }
- else
- {
- const BYTE* matchPtr = dictBase + matchIndex;
- if (LZ4_read32(matchPtr) == LZ4_read32(ip))
- {
- size_t mlt;
- int back=0;
- const BYTE* vLimit = ip + (dictLimit - matchIndex);
- if (vLimit > iHighLimit) vLimit = iHighLimit;
- mlt = LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, vLimit) + MINMATCH;
- if ((ip+mlt == vLimit) && (vLimit < iHighLimit))
- mlt += LZ4_count(ip+mlt, base+dictLimit, iHighLimit);
- while ((ip+back > iLowLimit) && (matchIndex+back > lowLimit) && (ip[back-1] == matchPtr[back-1])) back--;
- mlt -= back;
- if ((int)mlt > longest) { longest = (int)mlt; *matchpos = base + matchIndex + back; *startpos = ip+back; }
- }
- }
- matchIndex -= DELTANEXTU16(matchIndex);
- }
- return longest;
- }
- typedef enum { noLimit = 0, limitedOutput = 1 } limitedOutput_directive;
- #define LZ4HC_DEBUG 0
- #if LZ4HC_DEBUG
- static unsigned debug = 0;
- #endif
- FORCE_INLINE int LZ4HC_encodeSequence (
- const BYTE** ip,
- BYTE** op,
- const BYTE** anchor,
- int matchLength,
- const BYTE* const match,
- limitedOutput_directive limitedOutputBuffer,
- BYTE* oend)
- {
- int length;
- BYTE* token;
- #if LZ4HC_DEBUG
- if (debug) printf("literal : %u -- match : %u -- offset : %u\n", (U32)(*ip - *anchor), (U32)matchLength, (U32)(*ip-match));
- #endif
- /* Encode Literal length */
- length = (int)(*ip - *anchor);
- token = (*op)++;
- if ((limitedOutputBuffer) && ((*op + (length>>8) + length + (2 + 1 + LASTLITERALS)) > oend)) return 1; /* Check output limit */
- if (length>=(int)RUN_MASK) { int len; *token=(RUN_MASK<<ML_BITS); len = length-RUN_MASK; for(; len > 254 ; len-=255) *(*op)++ = 255; *(*op)++ = (BYTE)len; }
- else *token = (BYTE)(length<<ML_BITS);
- /* Copy Literals */
- LZ4_wildCopy(*op, *anchor, (*op) + length);
- *op += length;
- /* Encode Offset */
- LZ4_writeLE16(*op, (U16)(*ip-match)); *op += 2;
- /* Encode MatchLength */
- length = (int)(matchLength-MINMATCH);
- if ((limitedOutputBuffer) && (*op + (length>>8) + (1 + LASTLITERALS) > oend)) return 1; /* Check output limit */
- if (length>=(int)ML_MASK) { *token+=ML_MASK; length-=ML_MASK; for(; length > 509 ; length-=510) { *(*op)++ = 255; *(*op)++ = 255; } if (length > 254) { length-=255; *(*op)++ = 255; } *(*op)++ = (BYTE)length; }
- else *token += (BYTE)(length);
- /* Prepare next loop */
- *ip += matchLength;
- *anchor = *ip;
- return 0;
- }
- static int LZ4HC_compress_generic (
- void* ctxvoid,
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize,
- int compressionLevel,
- limitedOutput_directive limit
- )
- {
- LZ4HC_Data_Structure* ctx = (LZ4HC_Data_Structure*) ctxvoid;
- const BYTE* ip = (const BYTE*) source;
- const BYTE* anchor = ip;
- const BYTE* const iend = ip + inputSize;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = (iend - LASTLITERALS);
- BYTE* op = (BYTE*) dest;
- BYTE* const oend = op + maxOutputSize;
- unsigned maxNbAttempts;
- int ml, ml2, ml3, ml0;
- const BYTE* ref=NULL;
- const BYTE* start2=NULL;
- const BYTE* ref2=NULL;
- const BYTE* start3=NULL;
- const BYTE* ref3=NULL;
- const BYTE* start0;
- const BYTE* ref0;
- /* init */
- if (compressionLevel > g_maxCompressionLevel) compressionLevel = g_maxCompressionLevel;
- if (compressionLevel < 1) compressionLevel = LZ4HC_compressionLevel_default;
- maxNbAttempts = 1 << (compressionLevel-1);
- ctx->end += inputSize;
- ip++;
- /* Main Loop */
- while (ip < mflimit)
- {
- ml = LZ4HC_InsertAndFindBestMatch (ctx, ip, matchlimit, (&ref), maxNbAttempts);
- if (!ml) { ip++; continue; }
- /* saved, in case we would skip too much */
- start0 = ip;
- ref0 = ref;
- ml0 = ml;
- _Search2:
- if (ip+ml < mflimit)
- ml2 = LZ4HC_InsertAndGetWiderMatch(ctx, ip + ml - 2, ip + 1, matchlimit, ml, &ref2, &start2, maxNbAttempts);
- else ml2 = ml;
- if (ml2 == ml) /* No better match */
- {
- if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
- continue;
- }
- if (start0 < ip)
- {
- if (start2 < ip + ml0) /* empirical */
- {
- ip = start0;
- ref = ref0;
- ml = ml0;
- }
- }
- /* Here, start0==ip */
- if ((start2 - ip) < 3) /* First Match too small : removed */
- {
- ml = ml2;
- ip = start2;
- ref =ref2;
- goto _Search2;
- }
- _Search3:
- /*
- * Currently we have :
- * ml2 > ml1, and
- * ip1+3 <= ip2 (usually < ip1+ml1)
- */
- if ((start2 - ip) < OPTIMAL_ML)
- {
- int correction;
- int new_ml = ml;
- if (new_ml > OPTIMAL_ML) new_ml = OPTIMAL_ML;
- if (ip+new_ml > start2 + ml2 - MINMATCH) new_ml = (int)(start2 - ip) + ml2 - MINMATCH;
- correction = new_ml - (int)(start2 - ip);
- if (correction > 0)
- {
- start2 += correction;
- ref2 += correction;
- ml2 -= correction;
- }
- }
- /* Now, we have start2 = ip+new_ml, with new_ml = min(ml, OPTIMAL_ML=18) */
- if (start2 + ml2 < mflimit)
- ml3 = LZ4HC_InsertAndGetWiderMatch(ctx, start2 + ml2 - 3, start2, matchlimit, ml2, &ref3, &start3, maxNbAttempts);
- else ml3 = ml2;
- if (ml3 == ml2) /* No better match : 2 sequences to encode */
- {
- /* ip & ref are known; Now for ml */
- if (start2 < ip+ml) ml = (int)(start2 - ip);
- /* Now, encode 2 sequences */
- if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
- ip = start2;
- if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml2, ref2, limit, oend)) return 0;
- continue;
- }
- if (start3 < ip+ml+3) /* Not enough space for match 2 : remove it */
- {
- if (start3 >= (ip+ml)) /* can write Seq1 immediately ==> Seq2 is removed, so Seq3 becomes Seq1 */
- {
- if (start2 < ip+ml)
- {
- int correction = (int)(ip+ml - start2);
- start2 += correction;
- ref2 += correction;
- ml2 -= correction;
- if (ml2 < MINMATCH)
- {
- start2 = start3;
- ref2 = ref3;
- ml2 = ml3;
- }
- }
- if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
- ip = start3;
- ref = ref3;
- ml = ml3;
- start0 = start2;
- ref0 = ref2;
- ml0 = ml2;
- goto _Search2;
- }
- start2 = start3;
- ref2 = ref3;
- ml2 = ml3;
- goto _Search3;
- }
- /*
- * OK, now we have 3 ascending matches; let's write at least the first one
- * ip & ref are known; Now for ml
- */
- if (start2 < ip+ml)
- {
- if ((start2 - ip) < (int)ML_MASK)
- {
- int correction;
- if (ml > OPTIMAL_ML) ml = OPTIMAL_ML;
- if (ip + ml > start2 + ml2 - MINMATCH) ml = (int)(start2 - ip) + ml2 - MINMATCH;
- correction = ml - (int)(start2 - ip);
- if (correction > 0)
- {
- start2 += correction;
- ref2 += correction;
- ml2 -= correction;
- }
- }
- else
- {
- ml = (int)(start2 - ip);
- }
- }
- if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) return 0;
- ip = start2;
- ref = ref2;
- ml = ml2;
- start2 = start3;
- ref2 = ref3;
- ml2 = ml3;
- goto _Search3;
- }
- /* Encode Last Literals */
- {
- int lastRun = (int)(iend - anchor);
- if ((limit) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) return 0; /* Check output limit */
- if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun > 254 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
- else *op++ = (BYTE)(lastRun<<ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend-anchor;
- }
- /* End */
- return (int) (((char*)op)-dest);
- }
- int LZ4_sizeofStateHC(void) { return sizeof(LZ4HC_Data_Structure); }
- int LZ4_compress_HC_extStateHC (void* state, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel)
- {
- if (((size_t)(state)&(sizeof(void*)-1)) != 0) return 0; /* Error : state is not aligned for pointers (32 or 64 bits) */
- LZ4HC_init ((LZ4HC_Data_Structure*)state, (const BYTE*)src);
- if (maxDstSize < LZ4_compressBound(srcSize))
- return LZ4HC_compress_generic (state, src, dst, srcSize, maxDstSize, compressionLevel, limitedOutput);
- else
- return LZ4HC_compress_generic (state, src, dst, srcSize, maxDstSize, compressionLevel, noLimit);
- }
- int LZ4_compress_HC(const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel)
- {
- #if LZ4HC_HEAPMODE==1
- LZ4HC_Data_Structure* statePtr = malloc(sizeof(LZ4HC_Data_Structure));
- #else
- LZ4HC_Data_Structure state;
- LZ4HC_Data_Structure* const statePtr = &state;
- #endif
- int cSize = LZ4_compress_HC_extStateHC(statePtr, src, dst, srcSize, maxDstSize, compressionLevel);
- #if LZ4HC_HEAPMODE==1
- free(statePtr);
- #endif
- return cSize;
- }
- /**************************************
- * Streaming Functions
- **************************************/
- /* allocation */
- LZ4_streamHC_t* LZ4_createStreamHC(void) { return (LZ4_streamHC_t*)malloc(sizeof(LZ4_streamHC_t)); }
- int LZ4_freeStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr) { free(LZ4_streamHCPtr); return 0; }
- /* initialization */
- void LZ4_resetStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel)
- {
- LZ4_STATIC_ASSERT(sizeof(LZ4HC_Data_Structure) <= sizeof(LZ4_streamHC_t)); /* if compilation fails here, LZ4_STREAMHCSIZE must be increased */
- ((LZ4HC_Data_Structure*)LZ4_streamHCPtr)->base = NULL;
- ((LZ4HC_Data_Structure*)LZ4_streamHCPtr)->compressionLevel = (unsigned)compressionLevel;
- }
- int LZ4_loadDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, const char* dictionary, int dictSize)
- {
- LZ4HC_Data_Structure* ctxPtr = (LZ4HC_Data_Structure*) LZ4_streamHCPtr;
- if (dictSize > 64 KB)
- {
- dictionary += dictSize - 64 KB;
- dictSize = 64 KB;
- }
- LZ4HC_init (ctxPtr, (const BYTE*)dictionary);
- if (dictSize >= 4) LZ4HC_Insert (ctxPtr, (const BYTE*)dictionary +(dictSize-3));
- ctxPtr->end = (const BYTE*)dictionary + dictSize;
- return dictSize;
- }
- /* compression */
- static void LZ4HC_setExternalDict(LZ4HC_Data_Structure* ctxPtr, const BYTE* newBlock)
- {
- if (ctxPtr->end >= ctxPtr->base + 4)
- LZ4HC_Insert (ctxPtr, ctxPtr->end-3); /* Referencing remaining dictionary content */
- /* Only one memory segment for extDict, so any previous extDict is lost at this stage */
- ctxPtr->lowLimit = ctxPtr->dictLimit;
- ctxPtr->dictLimit = (U32)(ctxPtr->end - ctxPtr->base);
- ctxPtr->dictBase = ctxPtr->base;
- ctxPtr->base = newBlock - ctxPtr->dictLimit;
- ctxPtr->end = newBlock;
- ctxPtr->nextToUpdate = ctxPtr->dictLimit; /* match referencing will resume from there */
- }
- static int LZ4_compressHC_continue_generic (LZ4HC_Data_Structure* ctxPtr,
- const char* source, char* dest,
- int inputSize, int maxOutputSize, limitedOutput_directive limit)
- {
- /* auto-init if forgotten */
- if (ctxPtr->base == NULL)
- LZ4HC_init (ctxPtr, (const BYTE*) source);
- /* Check overflow */
- if ((size_t)(ctxPtr->end - ctxPtr->base) > 2 GB)
- {
- size_t dictSize = (size_t)(ctxPtr->end - ctxPtr->base) - ctxPtr->dictLimit;
- if (dictSize > 64 KB) dictSize = 64 KB;
- LZ4_loadDictHC((LZ4_streamHC_t*)ctxPtr, (const char*)(ctxPtr->end) - dictSize, (int)dictSize);
- }
- /* Check if blocks follow each other */
- if ((const BYTE*)source != ctxPtr->end)
- LZ4HC_setExternalDict(ctxPtr, (const BYTE*)source);
- /* Check overlapping input/dictionary space */
- {
- const BYTE* sourceEnd = (const BYTE*) source + inputSize;
- const BYTE* dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit;
- const BYTE* dictEnd = ctxPtr->dictBase + ctxPtr->dictLimit;
- if ((sourceEnd > dictBegin) && ((const BYTE*)source < dictEnd))
- {
- if (sourceEnd > dictEnd) sourceEnd = dictEnd;
- ctxPtr->lowLimit = (U32)(sourceEnd - ctxPtr->dictBase);
- if (ctxPtr->dictLimit - ctxPtr->lowLimit < 4) ctxPtr->lowLimit = ctxPtr->dictLimit;
- }
- }
- return LZ4HC_compress_generic (ctxPtr, source, dest, inputSize, maxOutputSize, ctxPtr->compressionLevel, limit);
- }
- int LZ4_compress_HC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize)
- {
- if (maxOutputSize < LZ4_compressBound(inputSize))
- return LZ4_compressHC_continue_generic ((LZ4HC_Data_Structure*)LZ4_streamHCPtr, source, dest, inputSize, maxOutputSize, limitedOutput);
- else
- return LZ4_compressHC_continue_generic ((LZ4HC_Data_Structure*)LZ4_streamHCPtr, source, dest, inputSize, maxOutputSize, noLimit);
- }
- /* dictionary saving */
- int LZ4_saveDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, char* safeBuffer, int dictSize)
- {
- LZ4HC_Data_Structure* streamPtr = (LZ4HC_Data_Structure*)LZ4_streamHCPtr;
- int prefixSize = (int)(streamPtr->end - (streamPtr->base + streamPtr->dictLimit));
- if (dictSize > 64 KB) dictSize = 64 KB;
- if (dictSize < 4) dictSize = 0;
- if (dictSize > prefixSize) dictSize = prefixSize;
- memmove(safeBuffer, streamPtr->end - dictSize, dictSize);
- {
- U32 endIndex = (U32)(streamPtr->end - streamPtr->base);
- streamPtr->end = (const BYTE*)safeBuffer + dictSize;
- streamPtr->base = streamPtr->end - endIndex;
- streamPtr->dictLimit = endIndex - dictSize;
- streamPtr->lowLimit = endIndex - dictSize;
- if (streamPtr->nextToUpdate < streamPtr->dictLimit) streamPtr->nextToUpdate = streamPtr->dictLimit;
- }
- return dictSize;
- }
- /***********************************
- * Deprecated Functions
- ***********************************/
- /* Deprecated compression functions */
- /* These functions are planned to start generate warnings by r131 approximately */
- int LZ4_compressHC(const char* src, char* dst, int srcSize) { return LZ4_compress_HC (src, dst, srcSize, LZ4_compressBound(srcSize), 0); }
- int LZ4_compressHC_limitedOutput(const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_HC(src, dst, srcSize, maxDstSize, 0); }
- int LZ4_compressHC2(const char* src, char* dst, int srcSize, int cLevel) { return LZ4_compress_HC (src, dst, srcSize, LZ4_compressBound(srcSize), cLevel); }
- int LZ4_compressHC2_limitedOutput(const char* src, char* dst, int srcSize, int maxDstSize, int cLevel) { return LZ4_compress_HC(src, dst, srcSize, maxDstSize, cLevel); }
- int LZ4_compressHC_withStateHC (void* state, const char* src, char* dst, int srcSize) { return LZ4_compress_HC_extStateHC (state, src, dst, srcSize, LZ4_compressBound(srcSize), 0); }
- int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_HC_extStateHC (state, src, dst, srcSize, maxDstSize, 0); }
- int LZ4_compressHC2_withStateHC (void* state, const char* src, char* dst, int srcSize, int cLevel) { return LZ4_compress_HC_extStateHC(state, src, dst, srcSize, LZ4_compressBound(srcSize), cLevel); }
- int LZ4_compressHC2_limitedOutput_withStateHC (void* state, const char* src, char* dst, int srcSize, int maxDstSize, int cLevel) { return LZ4_compress_HC_extStateHC(state, src, dst, srcSize, maxDstSize, cLevel); }
- int LZ4_compressHC_continue (LZ4_streamHC_t* ctx, const char* src, char* dst, int srcSize) { return LZ4_compress_HC_continue (ctx, src, dst, srcSize, LZ4_compressBound(srcSize)); }
- int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* ctx, const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_HC_continue (ctx, src, dst, srcSize, maxDstSize); }
- /* Deprecated streaming functions */
- /* These functions currently generate deprecation warnings */
- int LZ4_sizeofStreamStateHC(void) { return LZ4_STREAMHCSIZE; }
- int LZ4_resetStreamStateHC(void* state, char* inputBuffer)
- {
- if ((((size_t)state) & (sizeof(void*)-1)) != 0) return 1; /* Error : pointer is not aligned for pointer (32 or 64 bits) */
- LZ4HC_init((LZ4HC_Data_Structure*)state, (const BYTE*)inputBuffer);
- ((LZ4HC_Data_Structure*)state)->inputBuffer = (BYTE*)inputBuffer;
- return 0;
- }
- void* LZ4_createHC (char* inputBuffer)
- {
- void* hc4 = ALLOCATOR(1, sizeof(LZ4HC_Data_Structure));
- if (hc4 == NULL) return NULL; /* not enough memory */
- LZ4HC_init ((LZ4HC_Data_Structure*)hc4, (const BYTE*)inputBuffer);
- ((LZ4HC_Data_Structure*)hc4)->inputBuffer = (BYTE*)inputBuffer;
- return hc4;
- }
- int LZ4_freeHC (void* LZ4HC_Data)
- {
- FREEMEM(LZ4HC_Data);
- return (0);
- }
- int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel)
- {
- return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, 0, compressionLevel, noLimit);
- }
- int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel)
- {
- return LZ4HC_compress_generic (LZ4HC_Data, source, dest, inputSize, maxOutputSize, compressionLevel, limitedOutput);
- }
- char* LZ4_slideInputBufferHC(void* LZ4HC_Data)
- {
- LZ4HC_Data_Structure* hc4 = (LZ4HC_Data_Structure*)LZ4HC_Data;
- int dictSize = LZ4_saveDictHC((LZ4_streamHC_t*)LZ4HC_Data, (char*)(hc4->inputBuffer), 64 KB);
- return (char*)(hc4->inputBuffer + dictSize);
- }
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