diff options
Diffstat (limited to 'src/lib/lz4/lz4hc.c')
| -rw-r--r-- | src/lib/lz4/lz4hc.c | 671 |
1 files changed, 0 insertions, 671 deletions
diff --git a/src/lib/lz4/lz4hc.c b/src/lib/lz4/lz4hc.c deleted file mode 100644 index 2ab507e..0000000 --- a/src/lib/lz4/lz4hc.c +++ /dev/null @@ -1,671 +0,0 @@ -/*
- LZ4 HC - High Compression Mode of LZ4
- Copyright (C) 2011-2012, 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 homepage : http://fastcompression.blogspot.com/p/lz4.html
- - LZ4 source repository : http://code.google.com/p/lz4/
-*/
-
-
-//**************************************
-// CPU Feature Detection
-//**************************************
-// 32 or 64 bits ?
-#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) || defined(__amd64) || defined(__ppc64__) || defined(_WIN64) || defined(__LP64__) || defined(_LP64) ) // Detects 64 bits mode
-#define LZ4_ARCH64 1
-#else
-#define LZ4_ARCH64 0
-#endif
-
-// Little Endian or Big Endian ?
-#if (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN) || defined(_ARCH_PPC) || defined(__PPC__) || defined(__PPC) || defined(PPC) || defined(__powerpc__) || defined(__powerpc) || defined(powerpc) || ((defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))) )
-#define LZ4_BIG_ENDIAN 1
-#else
-// Little Endian assumed. PDP Endian and other very rare endian format are unsupported.
-#endif
-
-// Unaligned memory access is automatically enabled for "common" CPU, such as x86.
-// For others CPU, the compiler will be more cautious, and insert extra code to ensure aligned access is respected
-// If you know your target CPU supports unaligned memory access, you may want to force this option manually to improve performance
-#if defined(__ARM_FEATURE_UNALIGNED)
-#define LZ4_FORCE_UNALIGNED_ACCESS 1
-#endif
-
-
-//**************************************
-// Compiler Options
-//**************************************
-#if __STDC_VERSION__ >= 199901L // C99
- /* "restrict" is a known keyword */
-#else
-#define restrict // Disable restrict
-#endif
-
-#ifdef _MSC_VER
-#define inline __forceinline // Visual is not C99, but supports some kind of inline
-#include <intrin.h> // For Visual 2005
-# if LZ4_ARCH64 // 64-bit
-# pragma intrinsic(_BitScanForward64) // For Visual 2005
-# pragma intrinsic(_BitScanReverse64) // For Visual 2005
-# else
-# pragma intrinsic(_BitScanForward) // For Visual 2005
-# pragma intrinsic(_BitScanReverse) // For Visual 2005
-# endif
-#endif
-
-#ifdef _MSC_VER // Visual Studio
-#define lz4_bswap16(x) _byteswap_ushort(x)
-#else
-#define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
-#endif
-
-
-//**************************************
-// Includes
-//**************************************
-#include <stdlib.h> // calloc, free
-#include <string.h> // memset, memcpy
-#include "lz4hc.h"
-
-#define ALLOCATOR(s) calloc(1,s)
-#define FREEMEM free
-#define MEM_INIT memset
-
-
-//**************************************
-// Basic Types
-//**************************************
-#if defined(_MSC_VER) // Visual Studio does not support 'stdint' natively
-#define BYTE unsigned __int8
-#define U16 unsigned __int16
-#define U32 unsigned __int32
-#define S32 __int32
-#define U64 unsigned __int64
-#else
-#include <stdint.h>
-#define BYTE uint8_t
-#define U16 uint16_t
-#define U32 uint32_t
-#define S32 int32_t
-#define U64 uint64_t
-#endif
-
-#ifndef LZ4_FORCE_UNALIGNED_ACCESS
-#pragma pack(push, 1)
-#endif
-
-typedef struct _U16_S { U16 v; } U16_S;
-typedef struct _U32_S { U32 v; } U32_S;
-typedef struct _U64_S { U64 v; } U64_S;
-
-#ifndef LZ4_FORCE_UNALIGNED_ACCESS
-#pragma pack(pop)
-#endif
-
-#define A64(x) (((U64_S *)(x))->v)
-#define A32(x) (((U32_S *)(x))->v)
-#define A16(x) (((U16_S *)(x))->v)
-
-
-//**************************************
-// Constants
-//**************************************
-#define MINMATCH 4
-
-#define DICTIONARY_LOGSIZE 16
-#define MAXD (1<<DICTIONARY_LOGSIZE)
-#define MAXD_MASK ((U32)(MAXD - 1))
-#define MAX_DISTANCE (MAXD - 1)
-
-#define HASH_LOG (DICTIONARY_LOGSIZE-1)
-#define HASHTABLESIZE (1 << HASH_LOG)
-#define HASH_MASK (HASHTABLESIZE - 1)
-
-#define MAX_NB_ATTEMPTS 256
-
-#define ML_BITS 4
-#define ML_MASK (size_t)((1U<<ML_BITS)-1)
-#define RUN_BITS (8-ML_BITS)
-#define RUN_MASK ((1U<<RUN_BITS)-1)
-
-#define COPYLENGTH 8
-#define LASTLITERALS 5
-#define MFLIMIT (COPYLENGTH+MINMATCH)
-#define MINLENGTH (MFLIMIT+1)
-#define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH)
-
-
-//**************************************
-// Architecture-specific macros
-//**************************************
-#if LZ4_ARCH64 // 64-bit
-#define STEPSIZE 8
-#define LZ4_COPYSTEP(s,d) A64(d) = A64(s); d+=8; s+=8;
-#define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d)
-#define UARCH U64
-#define AARCH A64
-#define HTYPE U32
-#define INITBASE(b,s) const BYTE* const b = s
-#else // 32-bit
-#define STEPSIZE 4
-#define LZ4_COPYSTEP(s,d) A32(d) = A32(s); d+=4; s+=4;
-#define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d); LZ4_COPYSTEP(s,d);
-#define UARCH U32
-#define AARCH A32
-#define HTYPE const BYTE*
-#define INITBASE(b,s) const int b = 0
-#endif
-
-#if defined(LZ4_BIG_ENDIAN)
-#define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
-#define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }
-#else // Little Endian
-#define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }
-#define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; }
-#endif
-
-
-//************************************************************
-// Local Types
-//************************************************************
-typedef struct
-{
- const BYTE* base;
- HTYPE hashTable[HASHTABLESIZE];
- U16 chainTable[MAXD];
- const BYTE* nextToUpdate;
-} LZ4HC_Data_Structure;
-
-
-//**************************************
-// Macros
-//**************************************
-#define LZ4_WILDCOPY(s,d,e) do { LZ4_COPYPACKET(s,d) } while (d<e);
-#define LZ4_BLINDCOPY(s,d,l) { BYTE* e=d+l; LZ4_WILDCOPY(s,d,e); d=e; }
-#define HASH_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8)-HASH_LOG))
-#define HASH_VALUE(p) HASH_FUNCTION(*(U32*)(p))
-#define HASH_POINTER(p) (HashTable[HASH_VALUE(p)] + base)
-#define DELTANEXT(p) chainTable[(size_t)(p) & MAXD_MASK]
-#define GETNEXT(p) ((p) - (size_t)DELTANEXT(p))
-#define ADD_HASH(p) { size_t delta = (p) - HASH_POINTER(p); if (delta>MAX_DISTANCE) delta = MAX_DISTANCE; DELTANEXT(p) = (U16)delta; HashTable[HASH_VALUE(p)] = (p) - base; }
-
-
-//**************************************
-// Private functions
-//**************************************
-#if LZ4_ARCH64
-
-inline static int LZ4_NbCommonBytes (register U64 val)
-{
-#if defined(LZ4_BIG_ENDIAN)
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse64( &r, val );
- return (int)(r>>3);
- #elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clzll(val) >> 3);
- #else
- int r;
- if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
- if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
- r += (!val);
- return r;
- #endif
-#else
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanForward64( &r, val );
- return (int)(r>>3);
- #elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctzll(val) >> 3);
- #else
- static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
- return DeBruijnBytePos[((U64)((val & -val) * 0x0218A392CDABBD3F)) >> 58];
- #endif
-#endif
-}
-
-#else
-
-inline static int LZ4_NbCommonBytes (register U32 val)
-{
-#if defined(LZ4_BIG_ENDIAN)
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse( &r, val );
- return (int)(r>>3);
- #elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clz(val) >> 3);
- #else
- int r;
- if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
- r += (!val);
- return r;
- #endif
-#else
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanForward( &r, val );
- return (int)(r>>3);
- #elif defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctz(val) >> 3);
- #else
- static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
- return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
- #endif
-#endif
-}
-
-#endif
-
-
-inline static int LZ4HC_Init (LZ4HC_Data_Structure* hc4, const BYTE* base)
-{
- MEM_INIT((void*)hc4->hashTable, 0, sizeof(hc4->hashTable));
- MEM_INIT(hc4->chainTable, 0xFF, sizeof(hc4->chainTable));
- hc4->nextToUpdate = base + LZ4_ARCH64;
- hc4->base = base;
- return 1;
-}
-
-
-inline static void* LZ4HC_Create (const BYTE* base)
-{
- void* hc4 = ALLOCATOR(sizeof(LZ4HC_Data_Structure));
-
- LZ4HC_Init (hc4, base);
- return hc4;
-}
-
-
-inline static int LZ4HC_Free (void** LZ4HC_Data)
-{
- FREEMEM(*LZ4HC_Data);
- *LZ4HC_Data = NULL;
- return (1);
-}
-
-
-inline static void LZ4HC_Insert (LZ4HC_Data_Structure* hc4, const BYTE* ip)
-{
- U16* chainTable = hc4->chainTable;
- HTYPE* HashTable = hc4->hashTable;
- INITBASE(base,hc4->base);
-
- while(hc4->nextToUpdate < ip)
- {
- ADD_HASH(hc4->nextToUpdate);
- hc4->nextToUpdate++;
- }
-}
-
-
-inline static int LZ4HC_InsertAndFindBestMatch (LZ4HC_Data_Structure* hc4, const BYTE* ip, const BYTE* const matchlimit, const BYTE** matchpos)
-{
- U16* const chainTable = hc4->chainTable;
- HTYPE* const HashTable = hc4->hashTable;
- const BYTE* ref;
- INITBASE(base,hc4->base);
- int nbAttempts=MAX_NB_ATTEMPTS;
- int ml=0;
-
- // HC4 match finder
- LZ4HC_Insert(hc4, ip);
- ref = HASH_POINTER(ip);
- while ((ref > (ip-MAX_DISTANCE)) && (nbAttempts))
- {
- nbAttempts--;
- if (*(ref+ml) == *(ip+ml))
- if (*(U32*)ref == *(U32*)ip)
- {
- const BYTE* reft = ref+MINMATCH;
- const BYTE* ipt = ip+MINMATCH;
-
- while (ipt<matchlimit-(STEPSIZE-1))
- {
- UARCH diff = AARCH(reft) ^ AARCH(ipt);
- if (!diff) { ipt+=STEPSIZE; reft+=STEPSIZE; continue; }
- ipt += LZ4_NbCommonBytes(diff);
- goto _endCount;
- }
- if (LZ4_ARCH64) if ((ipt<(matchlimit-3)) && (A32(reft) == A32(ipt))) { ipt+=4; reft+=4; }
- if ((ipt<(matchlimit-1)) && (A16(reft) == A16(ipt))) { ipt+=2; reft+=2; }
- if ((ipt<matchlimit) && (*reft == *ipt)) ipt++;
-_endCount:
-
- if (ipt-ip > ml) { ml = (int)(ipt-ip); *matchpos = ref; }
- }
- ref = GETNEXT(ref);
- }
-
- return ml;
-}
-
-
-inline static int LZ4HC_InsertAndGetWiderMatch (LZ4HC_Data_Structure* hc4, const BYTE* ip, const BYTE* startLimit, const BYTE* matchlimit, int longest, const BYTE** matchpos, const BYTE** startpos)
-{
- U16* const chainTable = hc4->chainTable;
- HTYPE* const HashTable = hc4->hashTable;
- INITBASE(base,hc4->base);
- const BYTE* ref;
- int nbAttempts = MAX_NB_ATTEMPTS;
- int delta = (int)(ip-startLimit);
-
- // First Match
- LZ4HC_Insert(hc4, ip);
- ref = HASH_POINTER(ip);
-
- while ((ref > ip-MAX_DISTANCE) && (ref >= hc4->base) && (nbAttempts))
- {
- nbAttempts--;
- if (*(startLimit + longest) == *(ref - delta + longest))
- if (*(U32*)ref == *(U32*)ip)
- {
- const BYTE* reft = ref+MINMATCH;
- const BYTE* ipt = ip+MINMATCH;
- const BYTE* startt = ip;
-
- while (ipt<matchlimit-(STEPSIZE-1))
- {
- UARCH diff = AARCH(reft) ^ AARCH(ipt);
- if (!diff) { ipt+=STEPSIZE; reft+=STEPSIZE; continue; }
- ipt += LZ4_NbCommonBytes(diff);
- goto _endCount;
- }
- if (LZ4_ARCH64) if ((ipt<(matchlimit-3)) && (A32(reft) == A32(ipt))) { ipt+=4; reft+=4; }
- if ((ipt<(matchlimit-1)) && (A16(reft) == A16(ipt))) { ipt+=2; reft+=2; }
- if ((ipt<matchlimit) && (*reft == *ipt)) ipt++;
-_endCount:
-
- reft = ref;
- while ((startt>startLimit) && (reft > hc4->base) && (startt[-1] == reft[-1])) {startt--; reft--;}
-
- if ((ipt-startt) > longest)
- {
- longest = (int)(ipt-startt);
- *matchpos = reft;
- *startpos = startt;
- }
- }
- ref = GETNEXT(ref);
- }
-
- return longest;
-}
-
-
-inline static int LZ4_encodeSequence(const BYTE** ip, BYTE** op, const BYTE** anchor, int ml, const BYTE* ref)
-{
- int length, len;
- BYTE* token;
-
- // Encode Literal length
- length = (int)(*ip - *anchor);
- token = (*op)++;
- if (length>=(int)RUN_MASK) { *token=(RUN_MASK<<ML_BITS); len = length-RUN_MASK; for(; len > 254 ; len-=255) *(*op)++ = 255; *(*op)++ = (BYTE)len; }
- else *token = (length<<ML_BITS);
-
- // Copy Literals
- LZ4_BLINDCOPY(*anchor, *op, length);
-
- // Encode Offset
- LZ4_WRITE_LITTLEENDIAN_16(*op,(U16)(*ip-ref));
-
- // Encode MatchLength
- len = (int)(ml-MINMATCH);
- if (len>=(int)ML_MASK) { *token+=ML_MASK; len-=ML_MASK; for(; len > 509 ; len-=510) { *(*op)++ = 255; *(*op)++ = 255; } if (len > 254) { len-=255; *(*op)++ = 255; } *(*op)++ = (BYTE)len; }
- else *token += len;
-
- // Prepare next loop
- *ip += ml;
- *anchor = *ip;
-
- return 0;
-}
-
-
-//****************************
-// Compression CODE
-//****************************
-
-int LZ4_compressHCCtx(LZ4HC_Data_Structure* ctx,
- const char* source,
- char* dest,
- int isize)
-{
- const BYTE* ip = (const BYTE*) source;
- const BYTE* anchor = ip;
- const BYTE* const iend = ip + isize;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = (iend - LASTLITERALS);
-
- BYTE* op = (BYTE*) dest;
-
- 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;
-
- ip++;
-
- // Main Loop
- while (ip < mflimit)
- {
- ml = LZ4HC_InsertAndFindBestMatch (ctx, ip, matchlimit, (&ref));
- 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);
- else ml2=ml;
-
- if (ml2 == ml) // No better match
- {
- LZ4_encodeSequence(&ip, &op, &anchor, ml, ref);
- 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);
- else ml3=ml2;
-
- if (ml3 == ml2) // No better match : 2 sequences to encode
- {
- // ip & ref are known; Now for ml
- if (start2 < ip+ml)
- {
- if ((start2 - ip) < OPTIMAL_ML)
- {
- 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);
- }
- }
- // Now, encode 2 sequences
- LZ4_encodeSequence(&ip, &op, &anchor, ml, ref);
- ip = start2;
- LZ4_encodeSequence(&ip, &op, &anchor, ml2, ref2);
- 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;
- }
- }
-
- LZ4_encodeSequence(&ip, &op, &anchor, ml, ref);
- 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);
- }
- }
- LZ4_encodeSequence(&ip, &op, &anchor, ml, ref);
-
- ip = start2;
- ref = ref2;
- ml = ml2;
-
- start2 = start3;
- ref2 = ref3;
- ml2 = ml3;
-
- goto _Search3;
-
- }
-
- // Encode Last Literals
- {
- int lastRun = (int)(iend - anchor);
- 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++ = (lastRun<<ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend-anchor;
- }
-
- // End
- return (int) (((char*)op)-dest);
-}
-
-
-int LZ4_compressHC(const char* source,
- char* dest,
- int isize)
-{
- void* ctx = LZ4HC_Create((const BYTE*)source);
- int result = LZ4_compressHCCtx(ctx, source, dest, isize);
- LZ4HC_Free (&ctx);
-
- return result;
-}
-
-
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