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- /*
- LZ4 - Fast LZ compression algorithm
- 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 parameters
- **************************************/
- /*
- * HEAPMODE :
- * Select how default compression functions will allocate memory for their hash table,
- * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()).
- */
- #define HEAPMODE 0
- /*
- * ACCELERATION_DEFAULT :
- * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
- */
- #define ACCELERATION_DEFAULT 1
- /**************************************
- * CPU Feature Detection
- **************************************/
- /* LZ4_FORCE_MEMORY_ACCESS
- * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
- * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
- * The below switch allow to select different access method for improved performance.
- * Method 0 (default) : use `memcpy()`. Safe and portable.
- * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
- * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
- * Method 2 : direct access. This method is portable but violate C standard.
- * It can generate buggy code on targets which generate assembly depending on alignment.
- * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
- * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
- * Prefer these methods in priority order (0 > 1 > 2)
- */
- #ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */
- # if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
- # define LZ4_FORCE_MEMORY_ACCESS 2
- # elif defined(__INTEL_COMPILER) || \
- (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) ))
- # define LZ4_FORCE_MEMORY_ACCESS 1
- # endif
- #endif
- /*
- * LZ4_FORCE_SW_BITCOUNT
- * Define this parameter if your target system or compiler does not support hardware bit count
- */
- #if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE does not support Hardware bit count */
- # define LZ4_FORCE_SW_BITCOUNT
- #endif
- /**************************************
- * Includes
- **************************************/
- #include "lz4.h"
- /**************************************
- * Compiler Options
- **************************************/
- #ifdef _MSC_VER /* Visual Studio */
- # define FORCE_INLINE static __forceinline
- # include <intrin.h>
- # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
- # pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */
- #else
- # if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
- # if defined(__GNUC__) || defined(__clang__)
- # define FORCE_INLINE static inline __attribute__((always_inline))
- # else
- # define FORCE_INLINE static inline
- # endif
- # else
- # define FORCE_INLINE static
- # endif /* __STDC_VERSION__ */
- #endif /* _MSC_VER */
- /* LZ4_GCC_VERSION is defined into lz4.h */
- #if (LZ4_GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
- # define expect(expr,value) (__builtin_expect ((expr),(value)) )
- #else
- # define expect(expr,value) (expr)
- #endif
- #define likely(expr) expect((expr) != 0, 1)
- #define unlikely(expr) expect((expr) != 0, 0)
- /**************************************
- * Memory routines
- **************************************/
- #include <stdlib.h> /* malloc, calloc, free */
- #define ALLOCATOR(n,s) calloc(n,s)
- #define FREEMEM free
- #include <string.h> /* memset, memcpy */
- #define MEM_INIT memset
- /**************************************
- * Basic Types
- **************************************/
- #if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
- # include <stdint.h>
- typedef uint8_t BYTE;
- typedef uint16_t U16;
- typedef uint32_t U32;
- typedef int32_t S32;
- typedef uint64_t U64;
- #else
- typedef unsigned char BYTE;
- typedef unsigned short U16;
- typedef unsigned int U32;
- typedef signed int S32;
- typedef unsigned long long U64;
- #endif
- /**************************************
- * Reading and writing into memory
- **************************************/
- #define STEPSIZE sizeof(size_t)
- static unsigned LZ4_64bits(void) { return sizeof(void*)==8; }
- static unsigned LZ4_isLittleEndian(void)
- {
- const union { U32 i; BYTE c[4]; } one = { 1 }; // don't use static : performance detrimental
- return one.c[0];
- }
- #if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2)
- static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; }
- static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; }
- static size_t LZ4_read_ARCH(const void* memPtr) { return *(const size_t*) memPtr; }
- static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; }
- #elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1)
- /* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
- /* currently only defined for gcc and icc */
- typedef union { U16 u16; U32 u32; size_t uArch; } __attribute__((packed)) unalign;
- static U16 LZ4_read16(const void* ptr) { return ((const unalign*)ptr)->u16; }
- static U32 LZ4_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
- static size_t LZ4_read_ARCH(const void* ptr) { return ((const unalign*)ptr)->uArch; }
- static void LZ4_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; }
- #else
- static U16 LZ4_read16(const void* memPtr)
- {
- U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
- }
- static U32 LZ4_read32(const void* memPtr)
- {
- U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
- }
- static size_t LZ4_read_ARCH(const void* memPtr)
- {
- size_t val; memcpy(&val, memPtr, sizeof(val)); return val;
- }
- static void LZ4_write16(void* memPtr, U16 value)
- {
- memcpy(memPtr, &value, sizeof(value));
- }
- #endif // LZ4_FORCE_MEMORY_ACCESS
- static U16 LZ4_readLE16(const void* memPtr)
- {
- if (LZ4_isLittleEndian())
- {
- return LZ4_read16(memPtr);
- }
- else
- {
- const BYTE* p = (const BYTE*)memPtr;
- return (U16)((U16)p[0] + (p[1]<<8));
- }
- }
- static void LZ4_writeLE16(void* memPtr, U16 value)
- {
- if (LZ4_isLittleEndian())
- {
- LZ4_write16(memPtr, value);
- }
- else
- {
- BYTE* p = (BYTE*)memPtr;
- p[0] = (BYTE) value;
- p[1] = (BYTE)(value>>8);
- }
- }
- static void LZ4_copy8(void* dst, const void* src)
- {
- memcpy(dst,src,8);
- }
- /* customized variant of memcpy, which can overwrite up to 7 bytes beyond dstEnd */
- static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
- {
- BYTE* d = (BYTE*)dstPtr;
- const BYTE* s = (const BYTE*)srcPtr;
- BYTE* const e = (BYTE*)dstEnd;
- #if 0
- const size_t l2 = 8 - (((size_t)d) & (sizeof(void*)-1));
- LZ4_copy8(d,s); if (d>e-9) return;
- d+=l2; s+=l2;
- #endif /* join to align */
- do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e);
- }
- /**************************************
- * Common Constants
- **************************************/
- #define MINMATCH 4
- #define WILDCOPYLENGTH 8
- #define LASTLITERALS 5
- #define MFLIMIT (WILDCOPYLENGTH+MINMATCH)
- static const int LZ4_minLength = (MFLIMIT+1);
- #define KB *(1 <<10)
- #define MB *(1 <<20)
- #define GB *(1U<<30)
- #define MAXD_LOG 16
- #define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
- #define ML_BITS 4
- #define ML_MASK ((1U<<ML_BITS)-1)
- #define RUN_BITS (8-ML_BITS)
- #define RUN_MASK ((1U<<RUN_BITS)-1)
- /**************************************
- * Common Utils
- **************************************/
- #define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
- /**************************************
- * Common functions
- **************************************/
- static unsigned LZ4_NbCommonBytes (register size_t val)
- {
- if (LZ4_isLittleEndian())
- {
- if (LZ4_64bits())
- {
- # if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanForward64( &r, (U64)val );
- return (int)(r>>3);
- # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctzll((U64)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 & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
- # endif
- }
- else /* 32 bits */
- {
- # if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r;
- _BitScanForward( &r, (U32)val );
- return (int)(r>>3);
- # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctz((U32)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
- }
- }
- else /* Big Endian CPU */
- {
- if (LZ4_64bits())
- {
- # if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse64( &r, val );
- return (unsigned)(r>>3);
- # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clzll((U64)val) >> 3);
- # else
- unsigned 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 /* 32 bits */
- {
- # if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse( &r, (unsigned long)val );
- return (unsigned)(r>>3);
- # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clz((U32)val) >> 3);
- # else
- unsigned r;
- if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
- r += (!val);
- return r;
- # endif
- }
- }
- }
- static unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit)
- {
- const BYTE* const pStart = pIn;
- while (likely(pIn<pInLimit-(STEPSIZE-1)))
- {
- size_t diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
- if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; }
- pIn += LZ4_NbCommonBytes(diff);
- return (unsigned)(pIn - pStart);
- }
- if (LZ4_64bits()) if ((pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; }
- if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; }
- if ((pIn<pInLimit) && (*pMatch == *pIn)) pIn++;
- return (unsigned)(pIn - pStart);
- }
- #ifndef LZ4_COMMONDEFS_ONLY
- /**************************************
- * Local Constants
- **************************************/
- #define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
- #define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
- #define HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */
- static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT-1));
- static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression run slower on incompressible data */
- /**************************************
- * Local Structures and types
- **************************************/
- typedef struct {
- U32 hashTable[HASH_SIZE_U32];
- U32 currentOffset;
- U32 initCheck;
- const BYTE* dictionary;
- BYTE* bufferStart; /* obsolete, used for slideInputBuffer */
- U32 dictSize;
- } LZ4_stream_t_internal;
- typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
- typedef enum { byPtr, byU32, byU16 } tableType_t;
- typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
- typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
- typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
- typedef enum { full = 0, partial = 1 } earlyEnd_directive;
- /**************************************
- * Local Utils
- **************************************/
- int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; }
- int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
- int LZ4_sizeofState() { return LZ4_STREAMSIZE; }
- /********************************
- * Compression functions
- ********************************/
- static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType)
- {
- if (tableType == byU16)
- return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
- else
- return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
- }
- static const U64 prime5bytes = 889523592379ULL;
- static U32 LZ4_hashSequence64(size_t sequence, tableType_t const tableType)
- {
- const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG;
- const U32 hashMask = (1<<hashLog) - 1;
- return ((sequence * prime5bytes) >> (40 - hashLog)) & hashMask;
- }
- static U32 LZ4_hashSequenceT(size_t sequence, tableType_t const tableType)
- {
- if (LZ4_64bits())
- return LZ4_hashSequence64(sequence, tableType);
- return LZ4_hashSequence((U32)sequence, tableType);
- }
- static U32 LZ4_hashPosition(const void* p, tableType_t tableType) { return LZ4_hashSequenceT(LZ4_read_ARCH(p), tableType); }
- static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t const tableType, const BYTE* srcBase)
- {
- switch (tableType)
- {
- case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; }
- case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; }
- case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; }
- }
- }
- static void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
- {
- U32 h = LZ4_hashPosition(p, tableType);
- LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
- }
- static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
- {
- if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; }
- if (tableType == byU32) { U32* hashTable = (U32*) tableBase; return hashTable[h] + srcBase; }
- { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
- }
- static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
- {
- U32 h = LZ4_hashPosition(p, tableType);
- return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
- }
- FORCE_INLINE int LZ4_compress_generic(
- void* const ctx,
- const char* const source,
- char* const dest,
- const int inputSize,
- const int maxOutputSize,
- const limitedOutput_directive outputLimited,
- const tableType_t tableType,
- const dict_directive dict,
- const dictIssue_directive dictIssue,
- const U32 acceleration)
- {
- LZ4_stream_t_internal* const dictPtr = (LZ4_stream_t_internal*)ctx;
- const BYTE* ip = (const BYTE*) source;
- const BYTE* base;
- const BYTE* lowLimit;
- const BYTE* const lowRefLimit = ip - dictPtr->dictSize;
- const BYTE* const dictionary = dictPtr->dictionary;
- const BYTE* const dictEnd = dictionary + dictPtr->dictSize;
- const size_t dictDelta = dictEnd - (const BYTE*)source;
- const BYTE* anchor = (const BYTE*) source;
- const BYTE* const iend = ip + inputSize;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = iend - LASTLITERALS;
- BYTE* op = (BYTE*) dest;
- BYTE* const olimit = op + maxOutputSize;
- U32 forwardH;
- size_t refDelta=0;
- /* Init conditions */
- if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
- switch(dict)
- {
- case noDict:
- default:
- base = (const BYTE*)source;
- lowLimit = (const BYTE*)source;
- break;
- case withPrefix64k:
- base = (const BYTE*)source - dictPtr->currentOffset;
- lowLimit = (const BYTE*)source - dictPtr->dictSize;
- break;
- case usingExtDict:
- base = (const BYTE*)source - dictPtr->currentOffset;
- lowLimit = (const BYTE*)source;
- break;
- }
- if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
- if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
- /* First Byte */
- LZ4_putPosition(ip, ctx, tableType, base);
- ip++; forwardH = LZ4_hashPosition(ip, tableType);
- /* Main Loop */
- for ( ; ; )
- {
- const BYTE* match;
- BYTE* token;
- {
- const BYTE* forwardIp = ip;
- unsigned step = 1;
- unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
- /* Find a match */
- do {
- U32 h = forwardH;
- ip = forwardIp;
- forwardIp += step;
- step = (searchMatchNb++ >> LZ4_skipTrigger);
- if (unlikely(forwardIp > mflimit)) goto _last_literals;
- match = LZ4_getPositionOnHash(h, ctx, tableType, base);
- if (dict==usingExtDict)
- {
- if (match<(const BYTE*)source)
- {
- refDelta = dictDelta;
- lowLimit = dictionary;
- }
- else
- {
- refDelta = 0;
- lowLimit = (const BYTE*)source;
- }
- }
- forwardH = LZ4_hashPosition(forwardIp, tableType);
- LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
- } while ( ((dictIssue==dictSmall) ? (match < lowRefLimit) : 0)
- || ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
- || (LZ4_read32(match+refDelta) != LZ4_read32(ip)) );
- }
- /* Catch up */
- while ((ip>anchor) && (match+refDelta > lowLimit) && (unlikely(ip[-1]==match[refDelta-1]))) { ip--; match--; }
- {
- /* Encode Literal length */
- unsigned litLength = (unsigned)(ip - anchor);
- token = op++;
- if ((outputLimited) && (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)))
- return 0; /* Check output limit */
- if (litLength>=RUN_MASK)
- {
- int len = (int)litLength-RUN_MASK;
- *token=(RUN_MASK<<ML_BITS);
- for(; len >= 255 ; len-=255) *op++ = 255;
- *op++ = (BYTE)len;
- }
- else *token = (BYTE)(litLength<<ML_BITS);
- /* Copy Literals */
- LZ4_wildCopy(op, anchor, op+litLength);
- op+=litLength;
- }
- _next_match:
- /* Encode Offset */
- LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
- /* Encode MatchLength */
- {
- unsigned matchLength;
- if ((dict==usingExtDict) && (lowLimit==dictionary))
- {
- const BYTE* limit;
- match += refDelta;
- limit = ip + (dictEnd-match);
- if (limit > matchlimit) limit = matchlimit;
- matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, limit);
- ip += MINMATCH + matchLength;
- if (ip==limit)
- {
- unsigned more = LZ4_count(ip, (const BYTE*)source, matchlimit);
- matchLength += more;
- ip += more;
- }
- }
- else
- {
- matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
- ip += MINMATCH + matchLength;
- }
- if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) + (matchLength>>8) > olimit)))
- return 0; /* Check output limit */
- if (matchLength>=ML_MASK)
- {
- *token += ML_MASK;
- matchLength -= ML_MASK;
- for (; matchLength >= 510 ; matchLength-=510) { *op++ = 255; *op++ = 255; }
- if (matchLength >= 255) { matchLength-=255; *op++ = 255; }
- *op++ = (BYTE)matchLength;
- }
- else *token += (BYTE)(matchLength);
- }
- anchor = ip;
- /* Test end of chunk */
- if (ip > mflimit) break;
- /* Fill table */
- LZ4_putPosition(ip-2, ctx, tableType, base);
- /* Test next position */
- match = LZ4_getPosition(ip, ctx, tableType, base);
- if (dict==usingExtDict)
- {
- if (match<(const BYTE*)source)
- {
- refDelta = dictDelta;
- lowLimit = dictionary;
- }
- else
- {
- refDelta = 0;
- lowLimit = (const BYTE*)source;
- }
- }
- LZ4_putPosition(ip, ctx, tableType, base);
- if ( ((dictIssue==dictSmall) ? (match>=lowRefLimit) : 1)
- && (match+MAX_DISTANCE>=ip)
- && (LZ4_read32(match+refDelta)==LZ4_read32(ip)) )
- { token=op++; *token=0; goto _next_match; }
- /* Prepare next loop */
- forwardH = LZ4_hashPosition(++ip, tableType);
- }
- _last_literals:
- /* Encode Last Literals */
- {
- const size_t lastRun = (size_t)(iend - anchor);
- if ((outputLimited) && ((op - (BYTE*)dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize))
- return 0; /* Check output limit */
- if (lastRun >= RUN_MASK)
- {
- size_t accumulator = lastRun - RUN_MASK;
- *op++ = RUN_MASK << ML_BITS;
- for(; accumulator >= 255 ; accumulator-=255) *op++ = 255;
- *op++ = (BYTE) accumulator;
- }
- else
- {
- *op++ = (BYTE)(lastRun<<ML_BITS);
- }
- memcpy(op, anchor, lastRun);
- op += lastRun;
- }
- /* End */
- return (int) (((char*)op)-dest);
- }
- int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
- {
- LZ4_resetStream((LZ4_stream_t*)state);
- if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
- if (maxOutputSize >= LZ4_compressBound(inputSize))
- {
- if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
- else
- return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
- }
- else
- {
- if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
- else
- return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
- }
- }
- int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
- {
- #if (HEAPMODE)
- void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
- #else
- LZ4_stream_t ctx;
- void* ctxPtr = &ctx;
- #endif
- int result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
- #if (HEAPMODE)
- FREEMEM(ctxPtr);
- #endif
- return result;
- }
- int LZ4_compress_default(const char* source, char* dest, int inputSize, int maxOutputSize)
- {
- return LZ4_compress_fast(source, dest, inputSize, maxOutputSize, 1);
- }
- /* hidden debug function */
- /* strangely enough, gcc generates faster code when this function is uncommented, even if unused */
- int LZ4_compress_fast_force(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
- {
- LZ4_stream_t ctx;
- LZ4_resetStream(&ctx);
- if (inputSize < LZ4_64Klimit)
- return LZ4_compress_generic(&ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
- else
- return LZ4_compress_generic(&ctx, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
- }
- /********************************
- * destSize variant
- ********************************/
- static int LZ4_compress_destSize_generic(
- void* const ctx,
- const char* const src,
- char* const dst,
- int* const srcSizePtr,
- const int targetDstSize,
- const tableType_t tableType)
- {
- const BYTE* ip = (const BYTE*) src;
- const BYTE* base = (const BYTE*) src;
- const BYTE* lowLimit = (const BYTE*) src;
- const BYTE* anchor = ip;
- const BYTE* const iend = ip + *srcSizePtr;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = iend - LASTLITERALS;
- BYTE* op = (BYTE*) dst;
- BYTE* const oend = op + targetDstSize;
- BYTE* const oMaxLit = op + targetDstSize - 2 /* offset */ - 8 /* because 8+MINMATCH==MFLIMIT */ - 1 /* token */;
- BYTE* const oMaxMatch = op + targetDstSize - (LASTLITERALS + 1 /* token */);
- BYTE* const oMaxSeq = oMaxLit - 1 /* token */;
- U32 forwardH;
- /* Init conditions */
- if (targetDstSize < 1) return 0; /* Impossible to store anything */
- if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
- if ((tableType == byU16) && (*srcSizePtr>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
- if (*srcSizePtr<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
- /* First Byte */
- *srcSizePtr = 0;
- LZ4_putPosition(ip, ctx, tableType, base);
- ip++; forwardH = LZ4_hashPosition(ip, tableType);
- /* Main Loop */
- for ( ; ; )
- {
- const BYTE* match;
- BYTE* token;
- {
- const BYTE* forwardIp = ip;
- unsigned step = 1;
- unsigned searchMatchNb = 1 << LZ4_skipTrigger;
- /* Find a match */
- do {
- U32 h = forwardH;
- ip = forwardIp;
- forwardIp += step;
- step = (searchMatchNb++ >> LZ4_skipTrigger);
- if (unlikely(forwardIp > mflimit))
- goto _last_literals;
- match = LZ4_getPositionOnHash(h, ctx, tableType, base);
- forwardH = LZ4_hashPosition(forwardIp, tableType);
- LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
- } while ( ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
- || (LZ4_read32(match) != LZ4_read32(ip)) );
- }
- /* Catch up */
- while ((ip>anchor) && (match > lowLimit) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; }
- {
- /* Encode Literal length */
- unsigned litLength = (unsigned)(ip - anchor);
- token = op++;
- if (op + ((litLength+240)/255) + litLength > oMaxLit)
- {
- /* Not enough space for a last match */
- op--;
- goto _last_literals;
- }
- if (litLength>=RUN_MASK)
- {
- unsigned len = litLength - RUN_MASK;
- *token=(RUN_MASK<<ML_BITS);
- for(; len >= 255 ; len-=255) *op++ = 255;
- *op++ = (BYTE)len;
- }
- else *token = (BYTE)(litLength<<ML_BITS);
- /* Copy Literals */
- LZ4_wildCopy(op, anchor, op+litLength);
- op += litLength;
- }
- _next_match:
- /* Encode Offset */
- LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
- /* Encode MatchLength */
- {
- size_t matchLength;
- matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
- if (op + ((matchLength+240)/255) > oMaxMatch)
- {
- /* Match description too long : reduce it */
- matchLength = (15-1) + (oMaxMatch-op) * 255;
- }
- ip += MINMATCH + matchLength;
- if (matchLength>=ML_MASK)
- {
- *token += ML_MASK;
- matchLength -= ML_MASK;
- while (matchLength >= 255) { matchLength-=255; *op++ = 255; }
- *op++ = (BYTE)matchLength;
- }
- else *token += (BYTE)(matchLength);
- }
- anchor = ip;
- /* Test end of block */
- if (ip > mflimit) break;
- if (op > oMaxSeq) break;
- /* Fill table */
- LZ4_putPosition(ip-2, ctx, tableType, base);
- /* Test next position */
- match = LZ4_getPosition(ip, ctx, tableType, base);
- LZ4_putPosition(ip, ctx, tableType, base);
- if ( (match+MAX_DISTANCE>=ip)
- && (LZ4_read32(match)==LZ4_read32(ip)) )
- { token=op++; *token=0; goto _next_match; }
- /* Prepare next loop */
- forwardH = LZ4_hashPosition(++ip, tableType);
- }
- _last_literals:
- /* Encode Last Literals */
- {
- size_t lastRunSize = (size_t)(iend - anchor);
- if (op + 1 /* token */ + ((lastRunSize+240)/255) /* litLength */ + lastRunSize /* literals */ > oend)
- {
- /* adapt lastRunSize to fill 'dst' */
- lastRunSize = (oend-op) - 1;
- lastRunSize -= (lastRunSize+240)/255;
- }
- 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)-src);
- return (int) (((char*)op)-dst);
- }
- static int LZ4_compress_destSize_extState (void* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize)
- {
- LZ4_resetStream((LZ4_stream_t*)state);
- if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) /* compression success is guaranteed */
- {
- return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1);
- }
- else
- {
- if (*srcSizePtr < LZ4_64Klimit)
- return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr, targetDstSize, byU16);
- else
- return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr, targetDstSize, LZ4_64bits() ? byU32 : byPtr);
- }
- }
- int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize)
- {
- #if (HEAPMODE)
- void* ctx = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
- #else
- LZ4_stream_t ctxBody;
- void* ctx = &ctxBody;
- #endif
- int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize);
- #if (HEAPMODE)
- FREEMEM(ctx);
- #endif
- return result;
- }
- /********************************
- * Streaming functions
- ********************************/
- LZ4_stream_t* LZ4_createStream(void)
- {
- LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(8, LZ4_STREAMSIZE_U64);
- LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
- LZ4_resetStream(lz4s);
- return lz4s;
- }
- void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
- {
- MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
- }
- int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
- {
- FREEMEM(LZ4_stream);
- return (0);
- }
- #define HASH_UNIT sizeof(size_t)
- int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
- {
- LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
- const BYTE* p = (const BYTE*)dictionary;
- const BYTE* const dictEnd = p + dictSize;
- const BYTE* base;
- if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized structure, or reuse overflow */
- LZ4_resetStream(LZ4_dict);
- if (dictSize < (int)HASH_UNIT)
- {
- dict->dictionary = NULL;
- dict->dictSize = 0;
- return 0;
- }
- if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB;
- dict->currentOffset += 64 KB;
- base = p - dict->currentOffset;
- dict->dictionary = p;
- dict->dictSize = (U32)(dictEnd - p);
- dict->currentOffset += dict->dictSize;
- while (p <= dictEnd-HASH_UNIT)
- {
- LZ4_putPosition(p, dict->hashTable, byU32, base);
- p+=3;
- }
- return dict->dictSize;
- }
- static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
- {
- if ((LZ4_dict->currentOffset > 0x80000000) ||
- ((size_t)LZ4_dict->currentOffset > (size_t)src)) /* address space overflow */
- {
- /* rescale hash table */
- U32 delta = LZ4_dict->currentOffset - 64 KB;
- const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
- int i;
- for (i=0; i<HASH_SIZE_U32; i++)
- {
- if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0;
- else LZ4_dict->hashTable[i] -= delta;
- }
- LZ4_dict->currentOffset = 64 KB;
- if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB;
- LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
- }
- }
- int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
- {
- LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_stream;
- const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- const BYTE* smallest = (const BYTE*) source;
- if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */
- if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd;
- LZ4_renormDictT(streamPtr, smallest);
- if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
- /* Check overlapping input/dictionary space */
- {
- const BYTE* sourceEnd = (const BYTE*) source + inputSize;
- if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd))
- {
- streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
- if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB;
- if (streamPtr->dictSize < 4) streamPtr->dictSize = 0;
- streamPtr->dictionary = dictEnd - streamPtr->dictSize;
- }
- }
- /* prefix mode : source data follows dictionary */
- if (dictEnd == (const BYTE*)source)
- {
- int result;
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
- result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, dictSmall, acceleration);
- else
- result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, noDictIssue, acceleration);
- streamPtr->dictSize += (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
- return result;
- }
- /* external dictionary mode */
- {
- int result;
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
- result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, dictSmall, acceleration);
- else
- result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, noDictIssue, acceleration);
- streamPtr->dictionary = (const BYTE*)source;
- streamPtr->dictSize = (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
- return result;
- }
- }
- /* Hidden debug function, to force external dictionary mode */
- int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize)
- {
- LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_dict;
- int result;
- const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- const BYTE* smallest = dictEnd;
- if (smallest > (const BYTE*) source) smallest = (const BYTE*) source;
- LZ4_renormDictT((LZ4_stream_t_internal*)LZ4_dict, smallest);
- result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
- streamPtr->dictionary = (const BYTE*)source;
- streamPtr->dictSize = (U32)inputSize;
- streamPtr->currentOffset += (U32)inputSize;
- return result;
- }
- int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize)
- {
- LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
- const BYTE* previousDictEnd = dict->dictionary + dict->dictSize;
- if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a dictionary > 64 KB */
- if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize;
- memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
- dict->dictionary = (const BYTE*)safeBuffer;
- dict->dictSize = (U32)dictSize;
- return dictSize;
- }
- /*******************************
- * Decompression functions
- *******************************/
- /*
- * This generic decompression function cover all use cases.
- * It shall be instantiated several times, using different sets of directives
- * Note that it is essential this generic function is really inlined,
- * in order to remove useless branches during compilation optimization.
- */
- FORCE_INLINE int LZ4_decompress_generic(
- const char* const source,
- char* const dest,
- int inputSize,
- int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */
- int endOnInput, /* endOnOutputSize, endOnInputSize */
- int partialDecoding, /* full, partial */
- int targetOutputSize, /* only used if partialDecoding==partial */
- int dict, /* noDict, withPrefix64k, usingExtDict */
- const BYTE* const lowPrefix, /* == dest if dict == noDict */
- const BYTE* const dictStart, /* only if dict==usingExtDict */
- const size_t dictSize /* note : = 0 if noDict */
- )
- {
- /* Local Variables */
- const BYTE* ip = (const BYTE*) source;
- const BYTE* const iend = ip + inputSize;
- BYTE* op = (BYTE*) dest;
- BYTE* const oend = op + outputSize;
- BYTE* cpy;
- BYTE* oexit = op + targetOutputSize;
- const BYTE* const lowLimit = lowPrefix - dictSize;
- const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize;
- const unsigned dec32table[] = {4, 1, 2, 1, 4, 4, 4, 4};
- const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
- const int safeDecode = (endOnInput==endOnInputSize);
- const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
- /* Special cases */
- if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */
- if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
- if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1);
- /* Main Loop */
- while (1)
- {
- unsigned token;
- size_t length;
- const BYTE* match;
- size_t offset;
- /* get literal length */
- token = *ip++;
- if ((length=(token>>ML_BITS)) == RUN_MASK)
- {
- unsigned s;
- do
- {
- s = *ip++;
- length += s;
- }
- while ( likely(endOnInput ? ip<iend-RUN_MASK : 1) && (s==255) );
- if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)(op))) goto _output_error; /* overflow detection */
- if ((safeDecode) && unlikely((size_t)(ip+length)<(size_t)(ip))) goto _output_error; /* overflow detection */
- }
- /* copy literals */
- cpy = op+length;
- if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) )
- || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH)))
- {
- if (partialDecoding)
- {
- if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */
- if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */
- }
- else
- {
- if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */
- if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */
- }
- memcpy(op, ip, length);
- ip += length;
- op += length;
- break; /* Necessarily EOF, due to parsing restrictions */
- }
- LZ4_wildCopy(op, ip, cpy);
- ip += length; op = cpy;
- /* get offset */
- offset = LZ4_readLE16(ip); ip+=2;
- match = op - offset;
- if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside buffers */
- /* get matchlength */
- length = token & ML_MASK;
- if (length == ML_MASK)
- {
- unsigned s;
- do
- {
- if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error;
- s = *ip++;
- length += s;
- } while (s==255);
- if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* overflow detection */
- }
- length += MINMATCH;
- /* check external dictionary */
- if ((dict==usingExtDict) && (match < lowPrefix))
- {
- if (unlikely(op+length > oend-LASTLITERALS)) goto _output_error; /* doesn't respect parsing restriction */
- if (length <= (size_t)(lowPrefix-match))
- {
- /* match can be copied as a single segment from external dictionary */
- match = dictEnd - (lowPrefix-match);
- memmove(op, match, length); op += length;
- }
- else
- {
- /* match encompass external dictionary and current block */
- size_t copySize = (size_t)(lowPrefix-match);
- memcpy(op, dictEnd - copySize, copySize);
- op += copySize;
- copySize = length - copySize;
- if (copySize > (size_t)(op-lowPrefix)) /* overlap copy */
- {
- BYTE* const endOfMatch = op + copySize;
- const BYTE* copyFrom = lowPrefix;
- while (op < endOfMatch) *op++ = *copyFrom++;
- }
- else
- {
- memcpy(op, lowPrefix, copySize);
- op += copySize;
- }
- }
- continue;
- }
- /* copy match within block */
- cpy = op + length;
- if (unlikely(offset<8))
- {
- const int dec64 = dec64table[offset];
- op[0] = match[0];
- op[1] = match[1];
- op[2] = match[2];
- op[3] = match[3];
- match += dec32table[offset];
- memcpy(op+4, match, 4);
- match -= dec64;
- } else { LZ4_copy8(op, match); match+=8; }
- op += 8;
- if (unlikely(cpy>oend-12))
- {
- BYTE* const oCopyLimit = oend-(WILDCOPYLENGTH-1);
- if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last LASTLITERALS bytes must be literals (uncompressed) */
- if (op < oCopyLimit)
- {
- LZ4_wildCopy(op, match, oCopyLimit);
- match += oCopyLimit - op;
- op = oCopyLimit;
- }
- while (op<cpy) *op++ = *match++;
- }
- else
- LZ4_wildCopy(op, match, cpy);
- op=cpy; /* correction */
- }
- /* end of decoding */
- if (endOnInput)
- return (int) (((char*)op)-dest); /* Nb of output bytes decoded */
- else
- return (int) (((const char*)ip)-source); /* Nb of input bytes read */
- /* Overflow error detected */
- _output_error:
- return (int) (-(((const char*)ip)-source))-1;
- }
- int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize)
- {
- return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, full, 0, noDict, (BYTE*)dest, NULL, 0);
- }
- int LZ4_decompress_safe_partial(const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize)
- {
- return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, partial, targetOutputSize, noDict, (BYTE*)dest, NULL, 0);
- }
- int LZ4_decompress_fast(const char* source, char* dest, int originalSize)
- {
- return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, (BYTE*)(dest - 64 KB), NULL, 64 KB);
- }
- /* streaming decompression functions */
- typedef struct
- {
- const BYTE* externalDict;
- size_t extDictSize;
- const BYTE* prefixEnd;
- size_t prefixSize;
- } LZ4_streamDecode_t_internal;
- /*
- * If you prefer dynamic allocation methods,
- * LZ4_createStreamDecode()
- * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure.
- */
- LZ4_streamDecode_t* LZ4_createStreamDecode(void)
- {
- LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(1, sizeof(LZ4_streamDecode_t));
- return lz4s;
- }
- int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream)
- {
- FREEMEM(LZ4_stream);
- return 0;
- }
- /*
- * LZ4_setStreamDecode
- * Use this function to instruct where to find the dictionary
- * This function is not necessary if previous data is still available where it was decoded.
- * Loading a size of 0 is allowed (same effect as no dictionary).
- * Return : 1 if OK, 0 if error
- */
- int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize)
- {
- LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
- lz4sd->prefixSize = (size_t) dictSize;
- lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize;
- lz4sd->externalDict = NULL;
- lz4sd->extDictSize = 0;
- return 1;
- }
- /*
- *_continue() :
- These decoding functions allow decompression of multiple blocks in "streaming" mode.
- Previously decoded blocks must still be available at the memory position where they were decoded.
- If it's not possible, save the relevant part of decoded data into a safe buffer,
- and indicate where it stands using LZ4_setStreamDecode()
- */
- int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize)
- {
- LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
- int result;
- if (lz4sd->prefixEnd == (BYTE*)dest)
- {
- result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
- endOnInputSize, full, 0,
- usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
- if (result <= 0) return result;
- lz4sd->prefixSize += result;
- lz4sd->prefixEnd += result;
- }
- else
- {
- lz4sd->extDictSize = lz4sd->prefixSize;
- lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
- result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
- endOnInputSize, full, 0,
- usingExtDict, (BYTE*)dest, lz4sd->externalDict, lz4sd->extDictSize);
- if (result <= 0) return result;
- lz4sd->prefixSize = result;
- lz4sd->prefixEnd = (BYTE*)dest + result;
- }
- return result;
- }
- int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize)
- {
- LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
- int result;
- if (lz4sd->prefixEnd == (BYTE*)dest)
- {
- result = LZ4_decompress_generic(source, dest, 0, originalSize,
- endOnOutputSize, full, 0,
- usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
- if (result <= 0) return result;
- lz4sd->prefixSize += originalSize;
- lz4sd->prefixEnd += originalSize;
- }
- else
- {
- lz4sd->extDictSize = lz4sd->prefixSize;
- lz4sd->externalDict = (BYTE*)dest - lz4sd->extDictSize;
- result = LZ4_decompress_generic(source, dest, 0, originalSize,
- endOnOutputSize, full, 0,
- usingExtDict, (BYTE*)dest, lz4sd->externalDict, lz4sd->extDictSize);
- if (result <= 0) return result;
- lz4sd->prefixSize = originalSize;
- lz4sd->prefixEnd = (BYTE*)dest + originalSize;
- }
- return result;
- }
- /*
- Advanced decoding functions :
- *_usingDict() :
- These decoding functions work the same as "_continue" ones,
- the dictionary must be explicitly provided within parameters
- */
- FORCE_INLINE int LZ4_decompress_usingDict_generic(const char* source, char* dest, int compressedSize, int maxOutputSize, int safe, const char* dictStart, int dictSize)
- {
- if (dictSize==0)
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, noDict, (BYTE*)dest, NULL, 0);
- if (dictStart+dictSize == dest)
- {
- if (dictSize >= (int)(64 KB - 1))
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, withPrefix64k, (BYTE*)dest-64 KB, NULL, 0);
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, noDict, (BYTE*)dest-dictSize, NULL, 0);
- }
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
- }
- int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
- {
- return LZ4_decompress_usingDict_generic(source, dest, compressedSize, maxOutputSize, 1, dictStart, dictSize);
- }
- int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize)
- {
- return LZ4_decompress_usingDict_generic(source, dest, 0, originalSize, 0, dictStart, dictSize);
- }
- /* debug function */
- int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
- {
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
- }
- /***************************************************
- * Obsolete Functions
- ***************************************************/
- /* obsolete compression functions */
- int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) { return LZ4_compress_default(source, dest, inputSize, maxOutputSize); }
- int LZ4_compress(const char* source, char* dest, int inputSize) { return LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize)); }
- int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize) { return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1); }
- int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize) { return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1); }
- int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, maxDstSize, 1); }
- int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize) { return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1); }
- /*
- These function names are deprecated and should no longer be used.
- They are only provided here for compatibility with older user programs.
- - LZ4_uncompress is totally equivalent to LZ4_decompress_fast
- - LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
- */
- int LZ4_uncompress (const char* source, char* dest, int outputSize) { return LZ4_decompress_fast(source, dest, outputSize); }
- int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize, maxOutputSize); }
- /* Obsolete Streaming functions */
- int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; }
- static void LZ4_init(LZ4_stream_t_internal* lz4ds, BYTE* base)
- {
- MEM_INIT(lz4ds, 0, LZ4_STREAMSIZE);
- lz4ds->bufferStart = base;
- }
- int LZ4_resetStreamState(void* state, char* inputBuffer)
- {
- if ((((size_t)state) & 3) != 0) return 1; /* Error : pointer is not aligned on 4-bytes boundary */
- LZ4_init((LZ4_stream_t_internal*)state, (BYTE*)inputBuffer);
- return 0;
- }
- void* LZ4_create (char* inputBuffer)
- {
- void* lz4ds = ALLOCATOR(8, LZ4_STREAMSIZE_U64);
- LZ4_init ((LZ4_stream_t_internal*)lz4ds, (BYTE*)inputBuffer);
- return lz4ds;
- }
- char* LZ4_slideInputBuffer (void* LZ4_Data)
- {
- LZ4_stream_t_internal* ctx = (LZ4_stream_t_internal*)LZ4_Data;
- int dictSize = LZ4_saveDict((LZ4_stream_t*)LZ4_Data, (char*)ctx->bufferStart, 64 KB);
- return (char*)(ctx->bufferStart + dictSize);
- }
- /* Obsolete streaming decompression functions */
- int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize)
- {
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB);
- }
- int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize)
- {
- return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB);
- }
- #endif /* LZ4_COMMONDEFS_ONLY */
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