721 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			721 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | /*
 | ||
|  |     LZ4 HC - High Compression Mode of LZ4 | ||
|  |     Copyright (C) 2011-2016, 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 | ||
|  | ***************************************/ | ||
|  | #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 OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH)
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /**************************************
 | ||
|  | *  Local Macros | ||
|  | **************************************/ | ||
|  | #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(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_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) */ | ||
|  | 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(idx) = (U16)delta; | ||
|  |         hashTable[h] = idx; | ||
|  |         idx++; | ||
|  |     } | ||
|  | 
 | ||
|  |     hc4->nextToUpdate = target; | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | FORCE_INLINE int LZ4HC_InsertAndFindBestMatch (LZ4HC_CCtx_internal* 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; | ||
|  |     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) { | ||
|  |             const BYTE* const match = base + matchIndex; | ||
|  |             if (*(match+ml) == *(ip+ml) | ||
|  |                 && (LZ4_read32(match) == LZ4_read32(ip))) | ||
|  |             { | ||
|  |                 size_t const mlt = LZ4_count(ip+MINMATCH, match+MINMATCH, iLimit) + MINMATCH; | ||
|  |                 if (mlt > ml) { ml = mlt; *matchpos = match; } | ||
|  |             } | ||
|  |         } else { | ||
|  |             const BYTE* const 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_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) | ||
|  | { | ||
|  |     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* const 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; | ||
|  | } | ||
|  | 
 | ||
|  | #include "lz4opt.h"
 | ||
|  | 
 | ||
|  | static int LZ4HC_compress_hashChain ( | ||
|  |     LZ4HC_CCtx_internal* const ctx, | ||
|  |     const char* const source, | ||
|  |     char* const dest, | ||
|  |     int const inputSize, | ||
|  |     int const maxOutputSize, | ||
|  |     unsigned maxNbAttempts, | ||
|  |     limitedOutput_directive limit | ||
|  |     ) | ||
|  | { | ||
|  |     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; | ||
|  | 
 | ||
|  |     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 */ | ||
|  |     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 + 0, 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); | ||
|  | } | ||
|  | 
 | ||
|  | static int LZ4HC_getSearchNum(int compressionLevel) | ||
|  | { | ||
|  |     switch (compressionLevel) { | ||
|  |         default: return 0; /* unused */ | ||
|  |         case 11: return 128;  | ||
|  |         case 12: return 1<<10;  | ||
|  |     } | ||
|  | } | ||
|  | 
 | ||
|  | static int LZ4HC_compress_generic ( | ||
|  |     LZ4HC_CCtx_internal* const ctx, | ||
|  |     const char* const source, | ||
|  |     char* const dest, | ||
|  |     int const inputSize, | ||
|  |     int const maxOutputSize, | ||
|  |     int compressionLevel, | ||
|  |     limitedOutput_directive limit | ||
|  |     ) | ||
|  | { | ||
|  |     if (compressionLevel < 1) compressionLevel = LZ4HC_CLEVEL_DEFAULT; | ||
|  |     if (compressionLevel > 9) { | ||
|  |         switch (compressionLevel) { | ||
|  |             case 10: return LZ4HC_compress_hashChain(ctx, source, dest, inputSize, maxOutputSize, 1 << (16-1), limit); | ||
|  |             case 11: ctx->searchNum = LZ4HC_getSearchNum(compressionLevel); return LZ4HC_compress_optimal(ctx, source, dest, inputSize, maxOutputSize, limit, 128, 0); | ||
|  |             default: | ||
|  |             case 12: ctx->searchNum = LZ4HC_getSearchNum(compressionLevel); return LZ4HC_compress_optimal(ctx, source, dest, inputSize, maxOutputSize, limit, LZ4_OPT_NUM, 1); | ||
|  |         } | ||
|  |     } | ||
|  |     return LZ4HC_compress_hashChain(ctx, source, dest, inputSize, maxOutputSize, 1 << (compressionLevel-1), limit); | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | int LZ4_sizeofStateHC(void) { return sizeof(LZ4_streamHC_t); } | ||
|  | 
 | ||
|  | int LZ4_compress_HC_extStateHC (void* state, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel) | ||
|  | { | ||
|  |     LZ4HC_CCtx_internal* 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 (maxDstSize < LZ4_compressBound(srcSize)) | ||
|  |         return LZ4HC_compress_generic (ctx, src, dst, srcSize, maxDstSize, compressionLevel, limitedOutput); | ||
|  |     else | ||
|  |         return LZ4HC_compress_generic (ctx, src, dst, srcSize, maxDstSize, compressionLevel, noLimit); | ||
|  | } | ||
|  | 
 | ||
|  | int LZ4_compress_HC(const char* src, char* dst, int srcSize, int maxDstSize, 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, maxDstSize, compressionLevel); | ||
|  | #if defined(LZ4HC_HEAPMODE) && 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_CCtx_internal) <= sizeof(size_t) * LZ4_STREAMHCSIZE_SIZET);   /* if compilation fails here, LZ4_STREAMHCSIZE must be increased */ | ||
|  |     LZ4_streamHCPtr->internal_donotuse.base = NULL; | ||
|  |     LZ4_streamHCPtr->internal_donotuse.compressionLevel = (unsigned)compressionLevel; | ||
|  |     LZ4_streamHCPtr->internal_donotuse.searchNum = LZ4HC_getSearchNum(compressionLevel); | ||
|  | } | ||
|  | 
 | ||
|  | int LZ4_loadDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, const char* dictionary, int dictSize) | ||
|  | { | ||
|  |     LZ4HC_CCtx_internal* 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 (ctxPtr->compressionLevel >= LZ4HC_CLEVEL_OPT_MIN) | ||
|  |         LZ4HC_updateBinTree(ctxPtr, ctxPtr->end - MFLIMIT, ctxPtr->end - LASTLITERALS); | ||
|  |     else | ||
|  |         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->compressionLevel >= LZ4HC_CLEVEL_OPT_MIN) | ||
|  |         LZ4HC_updateBinTree(ctxPtr, ctxPtr->end - MFLIMIT, ctxPtr->end - LASTLITERALS); | ||
|  |     else | ||
|  |         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* source, char* dest, | ||
|  |                                             int inputSize, int maxOutputSize, limitedOutput_directive limit) | ||
|  | { | ||
|  |     LZ4HC_CCtx_internal* ctxPtr = &LZ4_streamHCPtr->internal_donotuse; | ||
|  |     /* 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_streamHCPtr, (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* const dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit; | ||
|  |         const BYTE* const 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 (LZ4_streamHCPtr, source, dest, inputSize, maxOutputSize, limitedOutput); | ||
|  |     else | ||
|  |         return LZ4_compressHC_continue_generic (LZ4_streamHCPtr, source, dest, inputSize, maxOutputSize, noLimit); | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | /* 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) { 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 (&((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse, 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 (&((LZ4_streamHC_t*)LZ4HC_Data)->internal_donotuse, source, dest, inputSize, maxOutputSize, compressionLevel, 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); | ||
|  | } |