| /* |
| 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_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]; |
| } |
| |
| |
| static U16 LZ4_read16(const void* memPtr) |
| { |
| U16 val16; |
| memcpy(&val16, memPtr, 2); |
| return val16; |
| } |
| |
| 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()) |
| { |
| memcpy(memPtr, &value, 2); |
| } |
| else |
| { |
| BYTE* p = (BYTE*)memPtr; |
| p[0] = (BYTE) value; |
| p[1] = (BYTE)(value>>8); |
| } |
| } |
| |
| static U32 LZ4_read32(const void* memPtr) |
| { |
| U32 val32; |
| memcpy(&val32, memPtr, 4); |
| return val32; |
| } |
| |
| static U64 LZ4_read64(const void* memPtr) |
| { |
| U64 val64; |
| memcpy(&val64, memPtr, 8); |
| return val64; |
| } |
| |
| static size_t LZ4_read_ARCH(const void* p) |
| { |
| if (LZ4_64bits()) |
| return (size_t)LZ4_read64(p); |
| else |
| return (size_t)LZ4_read32(p); |
| } |
| |
| |
| static void LZ4_copy4(void* dstPtr, const void* srcPtr) { memcpy(dstPtr, srcPtr, 4); } |
| |
| static void LZ4_copy8(void* dstPtr, const void* srcPtr) { memcpy(dstPtr, srcPtr, 8); } |
| |
| /* customized version of memcpy, which may 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* e = (BYTE*)dstEnd; |
| do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e); |
| } |
| |
| |
| /************************************** |
| * Common Constants |
| **************************************/ |
| #define MINMATCH 4 |
| |
| #define COPYLENGTH 8 |
| #define LASTLITERALS 5 |
| #define MFLIMIT (COPYLENGTH+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; |
| } |
| //printf("offset %5i, matchLength%5i \n", (int)(ip-match), matchLength + MINMATCH); |
| 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 size_t dec32table[] = {4, 1, 2, 1, 4, 4, 4, 4}; |
| const size_t dec64table[] = {0, 0, 0, (size_t)-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; |
| |
| /* 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-COPYLENGTH))) |
| { |
| 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 */ |
| match = cpy - LZ4_readLE16(ip); ip+=2; |
| if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside destination buffer */ |
| |
| /* 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 segment */ |
| size_t copySize = (size_t)(lowPrefix-match); |
| memcpy(op, dictEnd - copySize, copySize); |
| op += copySize; |
| copySize = length - copySize; |
| if (copySize > (size_t)(op-lowPrefix)) /* overlap within current segment */ |
| { |
| BYTE* const endOfMatch = op + copySize; |
| const BYTE* copyFrom = lowPrefix; |
| while (op < endOfMatch) *op++ = *copyFrom++; |
| } |
| else |
| { |
| memcpy(op, lowPrefix, copySize); |
| op += copySize; |
| } |
| } |
| continue; |
| } |
| |
| /* copy repeated sequence */ |
| cpy = op + length; |
| if (unlikely((op-match)<8)) |
| { |
| const size_t dec64 = dec64table[op-match]; |
| op[0] = match[0]; |
| op[1] = match[1]; |
| op[2] = match[2]; |
| op[3] = match[3]; |
| match += dec32table[op-match]; |
| LZ4_copy4(op+4, match); |
| op += 8; match -= dec64; |
| } else { LZ4_copy8(op, match); op+=8; match+=8; } |
| |
| if (unlikely(cpy>oend-12)) |
| { |
| if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last LASTLITERALS bytes must be literals */ |
| if (op < oend-8) |
| { |
| LZ4_wildCopy(op, match, oend-8); |
| match += (oend-8) - op; |
| op = oend-8; |
| } |
| 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 */ |
| |
