| /* |
| LZ4 HC - High Compression Mode of LZ4 |
| Copyright (C) 2011-2017, 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/lz4/lz4 |
| - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c |
| */ |
| /* note : lz4hc is not an independent module, it requires lz4.h/lz4.c for proper compilation */ |
| |
| |
| /* ************************************* |
| * Tuning Parameter |
| ***************************************/ |
| |
| /*! 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. |
| */ |
| #ifndef LZ4HC_HEAPMODE |
| # define LZ4HC_HEAPMODE 1 |
| #endif |
| |
| |
| /*=== Dependency ===*/ |
| #define LZ4_HC_STATIC_LINKING_ONLY |
| #include "lz4hc.h" |
| |
| |
| /*=== Common LZ4 definitions ===*/ |
| #if defined(__GNUC__) |
| # pragma GCC diagnostic ignored "-Wunused-function" |
| #endif |
| #if defined (__clang__) |
| # pragma clang diagnostic ignored "-Wunused-function" |
| #endif |
| |
| #define LZ4_COMMONDEFS_ONLY |
| #include "lz4.c" /* LZ4_count, constants, mem */ |
| |
| |
| /*=== Constants ===*/ |
| #define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH) |
| |
| |
| /*=== Macros ===*/ |
| #define MIN(a,b) ( (a) < (b) ? (a) : (b) ) |
| #define MAX(a,b) ( (a) > (b) ? (a) : (b) ) |
| #define HASH_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8)-LZ4HC_HASH_LOG)) |
| #define DELTANEXTMAXD(p) chainTable[(p) & LZ4HC_MAXD_MASK] /* flexible, LZ4HC_MAXD dependent */ |
| #define DELTANEXTU16(table, pos) table[(U16)(pos)] /* faster */ |
| |
| static U32 LZ4HC_hashPtr(const void* ptr) { return HASH_FUNCTION(LZ4_read32(ptr)); } |
| |
| |
| |
| /************************************** |
| * HC Compression |
| **************************************/ |
| static void LZ4HC_init (LZ4HC_CCtx_internal* 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) */ |
| LZ4_FORCE_INLINE void LZ4HC_Insert (LZ4HC_CCtx_internal* hc4, const BYTE* ip) |
| { |
| U16* const chainTable = hc4->chainTable; |
| U32* const hashTable = hc4->hashTable; |
| const BYTE* const base = hc4->base; |
| U32 const target = (U32)(ip - base); |
| U32 idx = hc4->nextToUpdate; |
| |
| while (idx < target) { |
| U32 const h = LZ4HC_hashPtr(base+idx); |
| size_t delta = idx - hashTable[h]; |
| if (delta>MAX_DISTANCE) delta = MAX_DISTANCE; |
| DELTANEXTU16(chainTable, idx) = (U16)delta; |
| hashTable[h] = idx; |
| idx++; |
| } |
| |
| hc4->nextToUpdate = target; |
| } |
| |
| /** LZ4HC_countBack() : |
| * @return : negative value, nb of common bytes before ip/match */ |
| LZ4_FORCE_INLINE |
| int LZ4HC_countBack(const BYTE* const ip, const BYTE* const match, |
| const BYTE* const iMin, const BYTE* const mMin) |
| { |
| int back = 0; |
| int const min = (int)MAX(iMin - ip, mMin - match); |
| assert(ip >= iMin); assert((size_t)(ip-iMin) < (1U<<31)); |
| assert(match >= mMin); assert((size_t)(match - mMin) < (1U<<31)); |
| while ( (back > min) |
| && (ip[back-1] == match[back-1]) ) |
| back--; |
| return back; |
| } |
| |
| /* LZ4HC_countPattern() : |
| * pattern32 must be a sample of repetitive pattern of length 1, 2 or 4 (but not 3!) */ |
| static unsigned |
| LZ4HC_countPattern(const BYTE* ip, const BYTE* const iEnd, U32 const pattern32) |
| { |
| const BYTE* const iStart = ip; |
| reg_t const pattern = (sizeof(pattern)==8) ? (reg_t)pattern32 + (((reg_t)pattern32) << 32) : pattern32; |
| |
| while (likely(ip < iEnd-(sizeof(pattern)-1))) { |
| reg_t const diff = LZ4_read_ARCH(ip) ^ pattern; |
| if (!diff) { ip+=sizeof(pattern); continue; } |
| ip += LZ4_NbCommonBytes(diff); |
| return (unsigned)(ip - iStart); |
| } |
| |
| if (LZ4_isLittleEndian()) { |
| reg_t patternByte = pattern; |
| while ((ip<iEnd) && (*ip == (BYTE)patternByte)) { |
| ip++; patternByte >>= 8; |
| } |
| } else { /* big endian */ |
| U32 bitOffset = (sizeof(pattern)*8) - 8; |
| while (ip < iEnd) { |
| BYTE const byte = (BYTE)(pattern >> bitOffset); |
| if (*ip != byte) break; |
| ip ++; bitOffset -= 8; |
| } |
| } |
| |
| return (unsigned)(ip - iStart); |
| } |
| |
| /* LZ4HC_reverseCountPattern() : |
| * pattern must be a sample of repetitive pattern of length 1, 2 or 4 (but not 3!) |
| * read using natural platform endianess */ |
| static unsigned |
| LZ4HC_reverseCountPattern(const BYTE* ip, const BYTE* const iLow, U32 pattern) |
| { |
| const BYTE* const iStart = ip; |
| |
| while (likely(ip >= iLow+4)) { |
| if (LZ4_read32(ip-4) != pattern) break; |
| ip -= 4; |
| } |
| { const BYTE* bytePtr = (const BYTE*)(&pattern) + 3; /* works for any endianess */ |
| while (likely(ip>iLow)) { |
| if (ip[-1] != *bytePtr) break; |
| ip--; bytePtr--; |
| } } |
| return (unsigned)(iStart - ip); |
| } |
| |
| typedef enum { rep_untested, rep_not, rep_confirmed } repeat_state_e; |
| |
| LZ4_FORCE_INLINE int |
| LZ4HC_InsertAndGetWiderMatch ( |
| LZ4HC_CCtx_internal* hc4, |
| const BYTE* const ip, |
| const BYTE* const iLowLimit, |
| const BYTE* const iHighLimit, |
| int longest, |
| const BYTE** matchpos, |
| const BYTE** startpos, |
| const int maxNbAttempts, |
| const int patternAnalysis) |
| { |
| 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) - MAX_DISTANCE; |
| const BYTE* const dictBase = hc4->dictBase; |
| int const delta = (int)(ip-iLowLimit); |
| int nbAttempts = maxNbAttempts; |
| U32 const pattern = LZ4_read32(ip); |
| U32 matchIndex; |
| repeat_state_e repeat = rep_untested; |
| size_t srcPatternLength = 0; |
| |
| DEBUGLOG(7, "LZ4HC_InsertAndGetWiderMatch"); |
| /* First Match */ |
| LZ4HC_Insert(hc4, ip); |
| matchIndex = HashTable[LZ4HC_hashPtr(ip)]; |
| DEBUGLOG(7, "First match at index %u / %u (lowLimit)", |
| matchIndex, lowLimit); |
| |
| while ((matchIndex>=lowLimit) && (nbAttempts)) { |
| DEBUGLOG(7, "remaining attempts : %i", nbAttempts); |
| nbAttempts--; |
| if (matchIndex >= dictLimit) { |
| const BYTE* const matchPtr = base + matchIndex; |
| assert(longest >= 1); |
| if (LZ4_read16(iLowLimit + longest - 1) == LZ4_read16(matchPtr - delta + longest - 1)) { |
| if (LZ4_read32(matchPtr) == pattern) { |
| int mlt = MINMATCH + LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, iHighLimit); |
| int const back = delta ? LZ4HC_countBack(ip, matchPtr, iLowLimit, lowPrefixPtr) : 0; |
| mlt -= back; |
| |
| if (mlt > longest) { |
| longest = mlt; |
| *matchpos = matchPtr+back; |
| *startpos = ip+back; |
| } } |
| } |
| } else { /* matchIndex < dictLimit */ |
| const BYTE* const matchPtr = dictBase + matchIndex; |
| if (LZ4_read32(matchPtr) == pattern) { |
| int 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); |
| back = delta ? LZ4HC_countBack(ip, matchPtr, iLowLimit, dictBase+lowLimit) : 0; |
| mlt -= back; |
| if (mlt > longest) { |
| longest = mlt; |
| *matchpos = base + matchIndex + back; |
| *startpos = ip + back; |
| } } } |
| |
| { U32 const nextOffset = DELTANEXTU16(chainTable, matchIndex); |
| matchIndex -= nextOffset; |
| if (patternAnalysis && nextOffset==1) { |
| /* may be a repeated pattern */ |
| if (repeat == rep_untested) { |
| if ( ((pattern & 0xFFFF) == (pattern >> 16)) |
| & ((pattern & 0xFF) == (pattern >> 24)) ) { |
| repeat = rep_confirmed; |
| srcPatternLength = LZ4HC_countPattern(ip+4, iHighLimit, pattern) + 4; |
| } else { |
| repeat = rep_not; |
| } } |
| if ( (repeat == rep_confirmed) |
| && (matchIndex >= dictLimit) ) { /* same segment only */ |
| const BYTE* const matchPtr = base + matchIndex; |
| if (LZ4_read32(matchPtr) == pattern) { /* good candidate */ |
| size_t const forwardPatternLength = LZ4HC_countPattern(matchPtr+sizeof(pattern), iHighLimit, pattern) + sizeof(pattern); |
| const BYTE* const maxLowPtr = (lowPrefixPtr + MAX_DISTANCE >= ip) ? lowPrefixPtr : ip - MAX_DISTANCE; |
| size_t const backLength = LZ4HC_reverseCountPattern(matchPtr, maxLowPtr, pattern); |
| size_t const currentSegmentLength = backLength + forwardPatternLength; |
| |
| if ( (currentSegmentLength >= srcPatternLength) /* current pattern segment large enough to contain full srcPatternLength */ |
| && (forwardPatternLength <= srcPatternLength) ) { /* haven't reached this position yet */ |
| matchIndex += (U32)forwardPatternLength - (U32)srcPatternLength; /* best position, full pattern, might be followed by more match */ |
| } else { |
| matchIndex -= (U32)backLength; /* let's go to farthest segment position, will find a match of length currentSegmentLength + maybe some back */ |
| } |
| } } } } |
| } /* while ((matchIndex>=lowLimit) && (nbAttempts)) */ |
| |
| return longest; |
| } |
| |
| LZ4_FORCE_INLINE |
| int LZ4HC_InsertAndFindBestMatch(LZ4HC_CCtx_internal* const hc4, /* Index table will be updated */ |
| const BYTE* const ip, const BYTE* const iLimit, |
| const BYTE** matchpos, |
| const int maxNbAttempts, |
| const int patternAnalysis) |
| { |
| const BYTE* uselessPtr = ip; |
| /* note : LZ4HC_InsertAndGetWiderMatch() is able to modify the starting position of a match (*startpos), |
| * but this won't be the case here, as we define iLowLimit==ip, |
| * so LZ4HC_InsertAndGetWiderMatch() won't be allowed to search past ip */ |
| return LZ4HC_InsertAndGetWiderMatch(hc4, ip, ip, iLimit, MINMATCH-1, matchpos, &uselessPtr, maxNbAttempts, patternAnalysis); |
| } |
| |
| |
| |
| typedef enum { |
| noLimit = 0, |
| limitedOutput = 1, |
| limitedDestSize = 2, |
| } limitedOutput_directive; |
| |
| /* LZ4HC_encodeSequence() : |
| * @return : 0 if ok, |
| * 1 if buffer issue detected */ |
| LZ4_FORCE_INLINE int LZ4HC_encodeSequence ( |
| const BYTE** ip, |
| BYTE** op, |
| const BYTE** anchor, |
| int matchLength, |
| const BYTE* const match, |
| limitedOutput_directive limit, |
| BYTE* oend) |
| { |
| size_t length; |
| BYTE* const token = (*op)++; |
| |
| #if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 6) |
| static const BYTE* start = NULL; |
| static U32 totalCost = 0; |
| U32 const pos = (start==NULL) ? 0 : (U32)(*anchor - start); |
| U32 const ll = (U32)(*ip - *anchor); |
| U32 const llAdd = (ll>=15) ? ((ll-15) / 255) + 1 : 0; |
| U32 const mlAdd = (matchLength>=19) ? ((matchLength-19) / 255) + 1 : 0; |
| U32 const cost = 1 + llAdd + ll + 2 + mlAdd; |
| if (start==NULL) start = *anchor; /* only works for single segment */ |
| //g_debuglog_enable = (pos >= 2228) & (pos <= 2262); |
| DEBUGLOG(6, "pos:%7u -- literals:%3u, match:%4i, offset:%5u, cost:%3u + %u", |
| pos, |
| (U32)(*ip - *anchor), matchLength, (U32)(*ip-match), |
| cost, totalCost); |
| totalCost += cost; |
| #endif |
| |
| /* Encode Literal length */ |
| length = (size_t)(*ip - *anchor); |
| if ((limit) && ((*op + (length >> 8) + length + (2 + 1 + LASTLITERALS)) > oend)) return 1; /* Check output limit */ |
| if (length >= RUN_MASK) { |
| size_t len = length - RUN_MASK; |
| *token = (RUN_MASK << ML_BITS); |
| for(; len >= 255 ; 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 */ |
| assert(matchLength >= MINMATCH); |
| length = (size_t)(matchLength - MINMATCH); |
| if ((limit) && (*op + (length >> 8) + (1 + LASTLITERALS) > oend)) return 1; /* Check output limit */ |
| if (length >= ML_MASK) { |
| *token += ML_MASK; |
| length -= ML_MASK; |
| for(; length >= 510 ; length -= 510) { *(*op)++ = 255; *(*op)++ = 255; } |
| if (length >= 255) { length -= 255; *(*op)++ = 255; } |
| *(*op)++ = (BYTE)length; |
| } else { |
| *token += (BYTE)(length); |
| } |
| |
| /* Prepare next loop */ |
| *ip += matchLength; |
| *anchor = *ip; |
| |
| return 0; |
| } |
| |
| /* btopt */ |
| #include "lz4opt.h" |
| |
| |
| static int LZ4HC_compress_hashChain ( |
| LZ4HC_CCtx_internal* const ctx, |
| const char* const source, |
| char* const dest, |
| int* srcSizePtr, |
| int const maxOutputSize, |
| unsigned maxNbAttempts, |
| limitedOutput_directive limit |
| ) |
| { |
| const int inputSize = *srcSizePtr; |
| const int patternAnalysis = (maxNbAttempts > 64); /* levels 8+ */ |
| |
| 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* optr = (BYTE*) dest; |
| BYTE* op = (BYTE*) dest; |
| BYTE* oend = op + maxOutputSize; |
| |
| 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 */ |
| *srcSizePtr = 0; |
| if (limit == limitedDestSize) oend -= LASTLITERALS; /* Hack for support LZ4 format restriction */ |
| if (inputSize < LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ |
| |
| /* Main Loop */ |
| while (ip <= mflimit) { |
| ml = LZ4HC_InsertAndFindBestMatch (ctx, ip, matchlimit, &ref, maxNbAttempts, patternAnalysis); |
| if (ml<MINMATCH) { 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 + 0, matchlimit, ml, &ref2, &start2, |
| maxNbAttempts, patternAnalysis); |
| else |
| ml2 = ml; |
| |
| if (ml2 == ml) { /* No better match */ |
| optr = op; |
| if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) goto _dest_overflow; |
| 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: |
| /* At this stage, 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, patternAnalysis); |
| 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 */ |
| optr = op; |
| if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) goto _dest_overflow; |
| ip = start2; |
| optr = op; |
| if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml2, ref2, limit, oend)) goto _dest_overflow; |
| 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; |
| } |
| } |
| |
| optr = op; |
| if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) goto _dest_overflow; |
| 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); |
| } |
| } |
| optr = op; |
| if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml, ref, limit, oend)) goto _dest_overflow; |
| |
| ip = start2; |
| ref = ref2; |
| ml = ml2; |
| |
| start2 = start3; |
| ref2 = ref3; |
| ml2 = ml3; |
| |
| goto _Search3; |
| } |
| |
| _last_literals: |
| /* Encode Last Literals */ |
| { size_t lastRunSize = (size_t)(iend - anchor); /* literals */ |
| size_t litLength = (lastRunSize + 255 - RUN_MASK) / 255; |
| size_t const totalSize = 1 + litLength + lastRunSize; |
| if (limit == limitedDestSize) oend += LASTLITERALS; /* restore correct value */ |
| if (limit && (op + totalSize > oend)) { |
| if (limit == limitedOutput) return 0; /* Check output limit */ |
| /* adapt lastRunSize to fill 'dest' */ |
| lastRunSize = (size_t)(oend - op) - 1; |
| litLength = (lastRunSize + 255 - RUN_MASK) / 255; |
| lastRunSize -= litLength; |
| } |
| ip = anchor + lastRunSize; |
| |
| if (lastRunSize >= RUN_MASK) { |
| size_t accumulator = lastRunSize - RUN_MASK; |
| *op++ = (RUN_MASK << ML_BITS); |
| for(; accumulator >= 255 ; accumulator -= 255) *op++ = 255; |
| *op++ = (BYTE) accumulator; |
| } else { |
| *op++ = (BYTE)(lastRunSize << ML_BITS); |
| } |
| memcpy(op, anchor, lastRunSize); |
| op += lastRunSize; |
| } |
| |
| /* End */ |
| *srcSizePtr = (int) (((const char*)ip) - source); |
| return (int) (((char*)op)-dest); |
| |
| _dest_overflow: |
| if (limit == limitedDestSize) { |
| op = optr; /* restore correct out pointer */ |
| goto _last_literals; |
| } |
| return 0; |
| } |
| |
| |
| static int LZ4HC_compress_generic ( |
| LZ4HC_CCtx_internal* const ctx, |
| const char* const src, |
| char* const dst, |
| int* const srcSizePtr, |
| int const dstCapacity, |
| int cLevel, |
| limitedOutput_directive limit |
| ) |
| { |
| typedef enum { lz4hc, lz4opt } lz4hc_strat_e; |
| typedef struct { |
| lz4hc_strat_e strat; |
| U32 nbSearches; |
| U32 targetLength; |
| } cParams_t; |
| static const cParams_t clTable[LZ4HC_CLEVEL_MAX+1] = { |
| { lz4hc, 2, 16 }, /* 0, unused */ |
| { lz4hc, 2, 16 }, /* 1, unused */ |
| { lz4hc, 2, 16 }, /* 2, unused */ |
| { lz4hc, 4, 16 }, /* 3 */ |
| { lz4hc, 8, 16 }, /* 4 */ |
| { lz4hc, 16, 16 }, /* 5 */ |
| { lz4hc, 32, 16 }, /* 6 */ |
| { lz4hc, 64, 16 }, /* 7 */ |
| { lz4hc, 128, 16 }, /* 8 */ |
| { lz4hc, 256, 16 }, /* 9 */ |
| { lz4opt, 96, 64 }, /*10==LZ4HC_CLEVEL_OPT_MIN*/ |
| { lz4opt, 512,128 }, /*11 */ |
| { lz4opt,8192, LZ4_OPT_NUM }, /* 12==LZ4HC_CLEVEL_MAX */ |
| }; |
| |
| if (limit == limitedDestSize && dstCapacity < 1) return 0; /* Impossible to store anything */ |
| if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size (too large or negative) */ |
| |
| ctx->end += *srcSizePtr; |
| if (cLevel < 1) cLevel = LZ4HC_CLEVEL_DEFAULT; /* note : convention is different from lz4frame, maybe something to review */ |
| cLevel = MIN(LZ4HC_CLEVEL_MAX, cLevel); |
| assert(cLevel >= 0); |
| assert(cLevel <= LZ4HC_CLEVEL_MAX); |
| { cParams_t const cParam = clTable[cLevel]; |
| if (cParam.strat == lz4hc) |
| return LZ4HC_compress_hashChain(ctx, |
| src, dst, srcSizePtr, dstCapacity, |
| cParam.nbSearches, limit); |
| assert(cParam.strat == lz4opt); |
| return LZ4HC_compress_optimal(ctx, |
| src, dst, srcSizePtr, dstCapacity, |
| cParam.nbSearches, cParam.targetLength, limit, |
| cLevel == LZ4HC_CLEVEL_MAX); /* ultra mode */ |
| } |
| } |
| |
| |
| int LZ4_sizeofStateHC(void) { return sizeof(LZ4_streamHC_t); } |
| |
| int LZ4_compress_HC_extStateHC (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel) |
| { |
| LZ4HC_CCtx_internal* const ctx = &((LZ4_streamHC_t*)state)->internal_donotuse; |
| if (((size_t)(state)&(sizeof(void*)-1)) != 0) return 0; /* Error : state is not aligned for pointers (32 or 64 bits) */ |
| LZ4HC_init (ctx, (const BYTE*)src); |
| if (dstCapacity < LZ4_compressBound(srcSize)) |
| return LZ4HC_compress_generic (ctx, src, dst, &srcSize, dstCapacity, compressionLevel, limitedOutput); |
| else |
| return LZ4HC_compress_generic (ctx, src, dst, &srcSize, dstCapacity, compressionLevel, noLimit); |
| } |
| |
| int LZ4_compress_HC(const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel) |
| { |
| #if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 |
| LZ4_streamHC_t* const statePtr = (LZ4_streamHC_t*)malloc(sizeof(LZ4_streamHC_t)); |
| #else |
| LZ4_streamHC_t state; |
| LZ4_streamHC_t* const statePtr = &state; |
| #endif |
| int const cSize = LZ4_compress_HC_extStateHC(statePtr, src, dst, srcSize, dstCapacity, compressionLevel); |
| #if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 |
| free(statePtr); |
| #endif |
| return cSize; |
| } |
| |
| /* LZ4_compress_HC_destSize() : |
| * only compatible with regular HC parser */ |
| int LZ4_compress_HC_destSize(void* LZ4HC_Data, const char* source, char* dest, int* sourceSizePtr, int targetDestSize, int cLevel) |
| { |
| LZ4HC_CCtx_internal* const ctx = &((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse; |
| LZ4HC_init(ctx, (const BYTE*) source); |
| return LZ4HC_compress_generic(ctx, source, dest, sourceSizePtr, targetDestSize, cLevel, limitedDestSize); |
| } |
| |
| |
| |
| /************************************** |
| * 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) { |
| if (!LZ4_streamHCPtr) return 0; /* support free on NULL */ |
| free(LZ4_streamHCPtr); |
| return 0; |
| } |
| |
| |
| /* initialization */ |
| void LZ4_resetStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel) |
| { |
| LZ4_STATIC_ASSERT(sizeof(LZ4HC_CCtx_internal) <= sizeof(size_t) * LZ4_STREAMHCSIZE_SIZET); /* if compilation fails here, LZ4_STREAMHCSIZE must be increased */ |
| LZ4_streamHCPtr->internal_donotuse.base = NULL; |
| LZ4_setCompressionLevel(LZ4_streamHCPtr, compressionLevel); |
| } |
| |
| void LZ4_setCompressionLevel(LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel) |
| { |
| if (compressionLevel < 1) compressionLevel = LZ4HC_CLEVEL_DEFAULT; |
| if (compressionLevel > LZ4HC_CLEVEL_MAX) compressionLevel = LZ4HC_CLEVEL_MAX; |
| LZ4_streamHCPtr->internal_donotuse.compressionLevel = compressionLevel; |
| } |
| |
| int LZ4_loadDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, const char* dictionary, int dictSize) |
| { |
| LZ4HC_CCtx_internal* const ctxPtr = &LZ4_streamHCPtr->internal_donotuse; |
| if (dictSize > 64 KB) { |
| dictionary += dictSize - 64 KB; |
| dictSize = 64 KB; |
| } |
| LZ4HC_init (ctxPtr, (const BYTE*)dictionary); |
| ctxPtr->end = (const BYTE*)dictionary + dictSize; |
| if (dictSize >= 4) LZ4HC_Insert (ctxPtr, ctxPtr->end-3); |
| return dictSize; |
| } |
| |
| |
| /* compression */ |
| |
| static void LZ4HC_setExternalDict(LZ4HC_CCtx_internal* 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 (LZ4_streamHC_t* LZ4_streamHCPtr, |
| const char* src, char* dst, |
| int* srcSizePtr, int dstCapacity, |
| limitedOutput_directive limit) |
| { |
| LZ4HC_CCtx_internal* const ctxPtr = &LZ4_streamHCPtr->internal_donotuse; |
| /* auto-init if forgotten */ |
| if (ctxPtr->base == NULL) LZ4HC_init (ctxPtr, (const BYTE*) src); |
| |
| /* 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_streamHCPtr, (const char*)(ctxPtr->end) - dictSize, (int)dictSize); |
| } |
| |
| /* Check if blocks follow each other */ |
| if ((const BYTE*)src != ctxPtr->end) LZ4HC_setExternalDict(ctxPtr, (const BYTE*)src); |
| |
| /* Check overlapping input/dictionary space */ |
| { const BYTE* sourceEnd = (const BYTE*) src + *srcSizePtr; |
| const BYTE* const dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit; |
| const BYTE* const dictEnd = ctxPtr->dictBase + ctxPtr->dictLimit; |
| if ((sourceEnd > dictBegin) && ((const BYTE*)src < 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, src, dst, srcSizePtr, dstCapacity, ctxPtr->compressionLevel, limit); |
| } |
| |
| int LZ4_compress_HC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* src, char* dst, int srcSize, int dstCapacity) |
| { |
| if (dstCapacity < LZ4_compressBound(srcSize)) |
| return LZ4_compressHC_continue_generic (LZ4_streamHCPtr, src, dst, &srcSize, dstCapacity, limitedOutput); |
| else |
| return LZ4_compressHC_continue_generic (LZ4_streamHCPtr, src, dst, &srcSize, dstCapacity, noLimit); |
| } |
| |
| int LZ4_compress_HC_continue_destSize (LZ4_streamHC_t* LZ4_streamHCPtr, const char* src, char* dst, int* srcSizePtr, int targetDestSize) |
| { |
| return LZ4_compressHC_continue_generic(LZ4_streamHCPtr, src, dst, srcSizePtr, targetDestSize, limitedDestSize); |
| } |
| |
| |
| |
| /* dictionary saving */ |
| |
| int LZ4_saveDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, char* safeBuffer, int dictSize) |
| { |
| LZ4HC_CCtx_internal* const streamPtr = &LZ4_streamHCPtr->internal_donotuse; |
| int const 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 const 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 |
| ***********************************/ |
| /* These functions currently generate deprecation warnings */ |
| /* Deprecated compression functions */ |
| 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 */ |
| int LZ4_sizeofStreamStateHC(void) { return LZ4_STREAMHCSIZE; } |
| |
| int LZ4_resetStreamStateHC(void* state, char* inputBuffer) |
| { |
| LZ4HC_CCtx_internal *ctx = &((LZ4_streamHC_t*)state)->internal_donotuse; |
| if ((((size_t)state) & (sizeof(void*)-1)) != 0) return 1; /* Error : pointer is not aligned for pointer (32 or 64 bits) */ |
| LZ4HC_init(ctx, (const BYTE*)inputBuffer); |
| ctx->inputBuffer = (BYTE*)inputBuffer; |
| return 0; |
| } |
| |
| void* LZ4_createHC (char* inputBuffer) |
| { |
| LZ4_streamHC_t* hc4 = (LZ4_streamHC_t*)ALLOCATOR(1, sizeof(LZ4_streamHC_t)); |
| if (hc4 == NULL) return NULL; /* not enough memory */ |
| LZ4HC_init (&hc4->internal_donotuse, (const BYTE*)inputBuffer); |
| hc4->internal_donotuse.inputBuffer = (BYTE*)inputBuffer; |
| return hc4; |
| } |
| |
| int LZ4_freeHC (void* LZ4HC_Data) { |
| if (!LZ4HC_Data) return 0; /* support free on NULL */ |
| FREEMEM(LZ4HC_Data); |
| return 0; |
| } |
| |
| int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* src, char* dst, int srcSize, int cLevel) |
| { |
| return LZ4HC_compress_generic (&((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse, src, dst, &srcSize, 0, cLevel, noLimit); |
| } |
| |
| int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* src, char* dst, int srcSize, int dstCapacity, int cLevel) |
| { |
| return LZ4HC_compress_generic (&((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse, src, dst, &srcSize, dstCapacity, cLevel, limitedOutput); |
| } |
| |
| char* LZ4_slideInputBufferHC(void* LZ4HC_Data) |
| { |
| LZ4HC_CCtx_internal* const hc4 = &((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse; |
| int const dictSize = LZ4_saveDictHC((LZ4_streamHC_t*)LZ4HC_Data, (char*)(hc4->inputBuffer), 64 KB); |
| return (char*)(hc4->inputBuffer + dictSize); |
| } |