1251 lines
44 KiB
C
1251 lines
44 KiB
C
/*
|
|
LZ4 - Fast LZ compression algorithm
|
|
Copyright (C) 2011-2014, 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 : http://code.google.com/p/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 memory allocation (malloc)).
|
|
*/
|
|
#define HEAPMODE 0
|
|
|
|
|
|
/**************************************
|
|
CPU Feature Detection
|
|
**************************************/
|
|
/* 32 or 64 bits ? */
|
|
#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \
|
|
|| defined(__powerpc64__) || defined(__powerpc64le__) \
|
|
|| defined(__ppc64__) || defined(__ppc64le__) \
|
|
|| defined(__PPC64__) || defined(__PPC64LE__) \
|
|
|| defined(__ia64) || defined(__itanium__) || defined(_M_IA64) ) /* Detects 64 bits mode */
|
|
# define LZ4_ARCH64 1
|
|
#else
|
|
# define LZ4_ARCH64 0
|
|
#endif
|
|
|
|
/*
|
|
* Little Endian or Big Endian ?
|
|
* Overwrite the #define below if you know your architecture endianess
|
|
*/
|
|
#include <stdlib.h> /* Apparently required to detect endianess */
|
|
#if defined (__GLIBC__)
|
|
# include <endian.h>
|
|
# if (__BYTE_ORDER == __BIG_ENDIAN)
|
|
# define LZ4_BIG_ENDIAN 1
|
|
# endif
|
|
#elif (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(__LITTLE_ENDIAN__) || defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN))
|
|
# define LZ4_BIG_ENDIAN 1
|
|
#elif defined(__sparc) || defined(__sparc__) \
|
|
|| defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \
|
|
|| defined(__hpux) || defined(__hppa) \
|
|
|| defined(_MIPSEB) || defined(__s390__)
|
|
# define LZ4_BIG_ENDIAN 1
|
|
#else
|
|
/* Little Endian assumed. PDP Endian and other very rare endian format are unsupported. */
|
|
#endif
|
|
|
|
/*
|
|
* Unaligned memory access is automatically enabled for "common" CPU, such as x86.
|
|
* For others CPU, such as ARM, the compiler may be more cautious, inserting unnecessary extra code to ensure aligned access property
|
|
* If you know your target CPU supports unaligned memory access, you want to force this option manually to improve performance
|
|
*/
|
|
#if defined(__ARM_FEATURE_UNALIGNED)
|
|
# define LZ4_FORCE_UNALIGNED_ACCESS 1
|
|
#endif
|
|
|
|
/* 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
|
|
|
|
/*
|
|
* BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :
|
|
* This option may provide a small boost to performance for some big endian cpu, although probably modest.
|
|
* You may set this option to 1 if data will remain within closed environment.
|
|
* This option is useless on Little_Endian CPU (such as x86)
|
|
*/
|
|
|
|
/* #define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1 */
|
|
|
|
|
|
/**************************************
|
|
Compiler Options
|
|
**************************************/
|
|
#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
|
|
/* "restrict" is a known keyword */
|
|
#else
|
|
# define restrict /* Disable restrict */
|
|
#endif
|
|
|
|
#ifdef _MSC_VER /* Visual Studio */
|
|
# define FORCE_INLINE static __forceinline
|
|
# include <intrin.h> /* For Visual 2005 */
|
|
# if LZ4_ARCH64 /* 64-bits */
|
|
# pragma intrinsic(_BitScanForward64) /* For Visual 2005 */
|
|
# pragma intrinsic(_BitScanReverse64) /* For Visual 2005 */
|
|
# else /* 32-bits */
|
|
# pragma intrinsic(_BitScanForward) /* For Visual 2005 */
|
|
# pragma intrinsic(_BitScanReverse) /* For Visual 2005 */
|
|
# endif
|
|
# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
|
|
#else
|
|
# ifdef __GNUC__
|
|
# define FORCE_INLINE static inline __attribute__((always_inline))
|
|
# else
|
|
# define FORCE_INLINE static inline
|
|
# endif
|
|
#endif
|
|
|
|
#ifdef _MSC_VER /* Visual Studio */
|
|
# define lz4_bswap16(x) _byteswap_ushort(x)
|
|
#else
|
|
# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
|
|
#endif
|
|
|
|
#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
|
|
|
|
#if (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
|
|
|
|
|
|
/**************************************
|
|
Includes
|
|
**************************************/
|
|
#include "lz4.h"
|
|
|
|
|
|
/**************************************
|
|
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
|
|
|
|
#if defined(__GNUC__) && !defined(LZ4_FORCE_UNALIGNED_ACCESS)
|
|
# define _PACKED __attribute__ ((packed))
|
|
#else
|
|
# define _PACKED
|
|
#endif
|
|
|
|
#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
|
|
# if defined(__IBMC__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
|
|
# pragma pack(1)
|
|
# else
|
|
# pragma pack(push, 1)
|
|
# endif
|
|
#endif
|
|
|
|
typedef struct { U16 v; } _PACKED U16_S;
|
|
typedef struct { U32 v; } _PACKED U32_S;
|
|
typedef struct { U64 v; } _PACKED U64_S;
|
|
typedef struct {size_t v;} _PACKED size_t_S;
|
|
|
|
#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
|
|
# if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
|
|
# pragma pack(0)
|
|
# else
|
|
# pragma pack(pop)
|
|
# endif
|
|
#endif
|
|
|
|
#define A16(x) (((U16_S *)(x))->v)
|
|
#define A32(x) (((U32_S *)(x))->v)
|
|
#define A64(x) (((U64_S *)(x))->v)
|
|
#define AARCH(x) (((size_t_S *)(x))->v)
|
|
|
|
|
|
/**************************************
|
|
Constants
|
|
**************************************/
|
|
#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
|
|
#define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
|
|
#define HASH_SIZE_U32 (1 << LZ4_HASHLOG)
|
|
|
|
#define MINMATCH 4
|
|
|
|
#define COPYLENGTH 8
|
|
#define LASTLITERALS 5
|
|
#define MFLIMIT (COPYLENGTH+MINMATCH)
|
|
static const int LZ4_minLength = (MFLIMIT+1);
|
|
|
|
#define KB *(1U<<10)
|
|
#define MB *(1U<<20)
|
|
#define GB *(1U<<30)
|
|
|
|
#define LZ4_64KLIMIT ((64 KB) + (MFLIMIT-1))
|
|
#define SKIPSTRENGTH 6 /* Increasing this value will make the compression run slower on incompressible data */
|
|
|
|
#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)
|
|
|
|
|
|
/**************************************
|
|
Structures and local types
|
|
**************************************/
|
|
typedef struct {
|
|
U32 hashTable[HASH_SIZE_U32];
|
|
U32 currentOffset;
|
|
U32 initCheck;
|
|
const BYTE* dictionary;
|
|
const BYTE* bufferStart;
|
|
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;
|
|
|
|
|
|
/**************************************
|
|
Architecture-specific macros
|
|
**************************************/
|
|
#define STEPSIZE sizeof(size_t)
|
|
#define LZ4_COPYSTEP(d,s) { AARCH(d) = AARCH(s); d+=STEPSIZE; s+=STEPSIZE; }
|
|
#define LZ4_COPY8(d,s) { LZ4_COPYSTEP(d,s); if (STEPSIZE<8) LZ4_COPYSTEP(d,s); }
|
|
|
|
#if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE))
|
|
# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
|
|
# define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }
|
|
#else /* Little Endian */
|
|
# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }
|
|
# define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; }
|
|
#endif
|
|
|
|
|
|
/**************************************
|
|
Macros
|
|
**************************************/
|
|
#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(!!(c)) }; } /* use only *after* variable declarations */
|
|
#if LZ4_ARCH64 || !defined(__GNUC__)
|
|
# define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); } /* at the end, d>=e; */
|
|
#else
|
|
# define LZ4_WILDCOPY(d,s,e) { if (likely(e-d <= 8)) LZ4_COPY8(d,s) else do { LZ4_COPY8(d,s) } while (d<e); }
|
|
#endif
|
|
|
|
|
|
/****************************
|
|
Private local functions
|
|
****************************/
|
|
#if LZ4_ARCH64
|
|
|
|
int LZ4_NbCommonBytes (register U64 val)
|
|
{
|
|
# if defined(LZ4_BIG_ENDIAN)
|
|
# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
unsigned long r = 0;
|
|
_BitScanReverse64( &r, val );
|
|
return (int)(r>>3);
|
|
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
return (__builtin_clzll(val) >> 3);
|
|
# else
|
|
int r;
|
|
if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
|
|
if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
|
|
r += (!val);
|
|
return r;
|
|
# endif
|
|
# else
|
|
# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
unsigned long r = 0;
|
|
_BitScanForward64( &r, val );
|
|
return (int)(r>>3);
|
|
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
return (__builtin_ctzll(val) >> 3);
|
|
# else
|
|
static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
|
|
return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
|
|
# endif
|
|
# endif
|
|
}
|
|
|
|
#else
|
|
|
|
int LZ4_NbCommonBytes (register U32 val)
|
|
{
|
|
# if defined(LZ4_BIG_ENDIAN)
|
|
# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
unsigned long r = 0;
|
|
_BitScanReverse( &r, val );
|
|
return (int)(r>>3);
|
|
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
return (__builtin_clz(val) >> 3);
|
|
# else
|
|
int r;
|
|
if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
|
|
r += (!val);
|
|
return r;
|
|
# endif
|
|
# else
|
|
# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
unsigned long r;
|
|
_BitScanForward( &r, val );
|
|
return (int)(r>>3);
|
|
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
return (__builtin_ctz(val) >> 3);
|
|
# else
|
|
static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
|
|
return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
|
|
# endif
|
|
# endif
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
/********************************
|
|
Compression functions
|
|
********************************/
|
|
int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
|
|
|
|
static int LZ4_hashSequence(U32 sequence, tableType_t tableType)
|
|
{
|
|
if (tableType == byU16)
|
|
return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
|
|
else
|
|
return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
|
|
}
|
|
|
|
static int LZ4_hashPosition(const BYTE* p, tableType_t tableType) { return LZ4_hashSequence(A32(p), tableType); }
|
|
|
|
static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
|
|
{
|
|
switch (tableType)
|
|
{
|
|
case byPtr: { const BYTE** hashTable = (const BYTE**) tableBase; hashTable[h] = p; break; }
|
|
case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); break; }
|
|
case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); break; }
|
|
}
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static unsigned LZ4_count(const BYTE* pIn, const BYTE* pRef, const BYTE* pInLimit)
|
|
{
|
|
const BYTE* const pStart = pIn;
|
|
|
|
while (likely(pIn<pInLimit-(STEPSIZE-1)))
|
|
{
|
|
size_t diff = AARCH(pRef) ^ AARCH(pIn);
|
|
if (!diff) { pIn+=STEPSIZE; pRef+=STEPSIZE; continue; }
|
|
pIn += LZ4_NbCommonBytes(diff);
|
|
return (unsigned)(pIn - pStart);
|
|
}
|
|
if (sizeof(void*)==8) if ((pIn<(pInLimit-3)) && (A32(pRef) == A32(pIn))) { pIn+=4; pRef+=4; }
|
|
if ((pIn<(pInLimit-1)) && (A16(pRef) == A16(pIn))) { pIn+=2; pRef+=2; }
|
|
if ((pIn<pInLimit) && (*pRef == *pIn)) pIn++;
|
|
|
|
return (unsigned)(pIn - pStart);
|
|
}
|
|
|
|
|
|
static int LZ4_compress_generic(
|
|
void* ctx,
|
|
const char* source,
|
|
char* dest,
|
|
int inputSize,
|
|
int maxOutputSize,
|
|
|
|
limitedOutput_directive outputLimited,
|
|
tableType_t tableType,
|
|
dict_directive dict,
|
|
dictIssue_directive dictIssue)
|
|
{
|
|
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;
|
|
|
|
const int skipStrength = SKIPSTRENGTH;
|
|
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>=(int)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* ref;
|
|
BYTE* token;
|
|
{
|
|
const BYTE* forwardIp = ip;
|
|
unsigned step=1;
|
|
unsigned searchMatchNb = (1U << skipStrength);
|
|
|
|
/* Find a match */
|
|
do {
|
|
U32 h = forwardH;
|
|
ip = forwardIp;
|
|
forwardIp += step;
|
|
step = searchMatchNb++ >> skipStrength;
|
|
//if (step>8) step=8; // required for valid forwardIp ; slows down uncompressible data a bit
|
|
|
|
if (unlikely(forwardIp > mflimit)) goto _last_literals;
|
|
|
|
ref = LZ4_getPositionOnHash(h, ctx, tableType, base);
|
|
if (dict==usingExtDict)
|
|
{
|
|
if (ref<(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) ? (ref < lowRefLimit) : 0)
|
|
|| ((tableType==byU16) ? 0 : (ref + MAX_DISTANCE < ip))
|
|
|| (A32(ref+refDelta) != A32(ip)) );
|
|
}
|
|
|
|
/* Catch up */
|
|
while ((ip>anchor) && (ref+refDelta > lowLimit) && (unlikely(ip[-1]==ref[refDelta-1]))) { ip--; ref--; }
|
|
|
|
{
|
|
/* 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 */
|
|
{ BYTE* end = op+litLength; LZ4_WILDCOPY(op,anchor,end); op=end; }
|
|
}
|
|
|
|
_next_match:
|
|
/* Encode Offset */
|
|
LZ4_WRITE_LITTLEENDIAN_16(op, (U16)(ip-ref));
|
|
|
|
/* Encode MatchLength */
|
|
{
|
|
unsigned matchLength;
|
|
|
|
if ((dict==usingExtDict) && (lowLimit==dictionary))
|
|
{
|
|
const BYTE* limit;
|
|
ref += refDelta;
|
|
limit = ip + (dictEnd-ref);
|
|
if (limit > matchlimit) limit = matchlimit;
|
|
matchLength = LZ4_count(ip+MINMATCH, ref+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, ref+MINMATCH, matchlimit);
|
|
ip += MINMATCH + matchLength;
|
|
}
|
|
|
|
if (matchLength>=ML_MASK)
|
|
{
|
|
if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) + (matchLength>>8) > olimit)))
|
|
return 0; /* Check output limit */
|
|
*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 */
|
|
ref = LZ4_getPosition(ip, ctx, tableType, base);
|
|
if (dict==usingExtDict)
|
|
{
|
|
if (ref<(const BYTE*)source)
|
|
{
|
|
refDelta = dictDelta;
|
|
lowLimit = dictionary;
|
|
}
|
|
else
|
|
{
|
|
refDelta = 0;
|
|
lowLimit = (const BYTE*)source;
|
|
}
|
|
}
|
|
LZ4_putPosition(ip, ctx, tableType, base);
|
|
if ( ((dictIssue==dictSmall) ? (ref>=lowRefLimit) : 1)
|
|
&& (ref+MAX_DISTANCE>=ip)
|
|
&& (A32(ref+refDelta)==A32(ip)) )
|
|
{ token=op++; *token=0; goto _next_match; }
|
|
|
|
/* Prepare next loop */
|
|
forwardH = LZ4_hashPosition(++ip, tableType);
|
|
}
|
|
|
|
_last_literals:
|
|
/* Encode Last Literals */
|
|
{
|
|
int lastRun = (int)(iend - anchor);
|
|
if ((outputLimited) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize))
|
|
return 0; /* Check output limit */
|
|
if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun >= 255 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
|
|
else *op++ = (BYTE)(lastRun<<ML_BITS);
|
|
memcpy(op, anchor, iend - anchor);
|
|
op += iend-anchor;
|
|
}
|
|
|
|
/* End */
|
|
return (int) (((char*)op)-dest);
|
|
}
|
|
|
|
|
|
int LZ4_compress(const char* source, char* dest, int inputSize)
|
|
{
|
|
#if (HEAPMODE)
|
|
void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */
|
|
#else
|
|
U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */
|
|
#endif
|
|
int result;
|
|
|
|
if (inputSize < (int)LZ4_64KLIMIT)
|
|
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue);
|
|
else
|
|
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue);
|
|
|
|
#if (HEAPMODE)
|
|
FREEMEM(ctx);
|
|
#endif
|
|
return result;
|
|
}
|
|
|
|
int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
|
|
{
|
|
#if (HEAPMODE)
|
|
void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */
|
|
#else
|
|
U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */
|
|
#endif
|
|
int result;
|
|
|
|
if (inputSize < (int)LZ4_64KLIMIT)
|
|
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue);
|
|
else
|
|
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue);
|
|
|
|
#if (HEAPMODE)
|
|
FREEMEM(ctx);
|
|
#endif
|
|
return result;
|
|
}
|
|
|
|
|
|
/*****************************************
|
|
Experimental : Streaming functions
|
|
*****************************************/
|
|
|
|
void* LZ4_createStream()
|
|
{
|
|
void* lz4s = ALLOCATOR(4, LZ4_STREAMSIZE_U32);
|
|
if (!lz4s) return NULL;
|
|
MEM_INIT(lz4s, 0, LZ4_STREAMSIZE);
|
|
return lz4s;
|
|
}
|
|
|
|
int LZ4_free (void* LZ4_stream)
|
|
{
|
|
FREEMEM(LZ4_stream);
|
|
return (0);
|
|
}
|
|
|
|
|
|
int LZ4_loadDict (void* 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;
|
|
|
|
LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
|
|
if (dict->initCheck) MEM_INIT(dict, 0, sizeof(LZ4_stream_t_internal)); /* Uninitialized structure detected */
|
|
|
|
if (dictSize < MINMATCH)
|
|
{
|
|
dict->dictionary = NULL;
|
|
dict->dictSize = 0;
|
|
return 1;
|
|
}
|
|
|
|
if (p <= dictEnd - 64 KB) p = dictEnd - 64 KB;
|
|
base = p - dict->currentOffset;
|
|
dict->dictionary = p;
|
|
dict->dictSize = (U32)(dictEnd - p);
|
|
dict->currentOffset += dict->dictSize;
|
|
|
|
while (p <= dictEnd-MINMATCH)
|
|
{
|
|
LZ4_putPosition(p, dict, byU32, base);
|
|
p+=3;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
|
|
FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* source, char* dest, int inputSize,
|
|
int maxOutputSize, limitedOutput_directive limit)
|
|
{
|
|
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);
|
|
|
|
/* 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, limit, byU32, withPrefix64k, dictSmall);
|
|
else
|
|
result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, withPrefix64k, noDictIssue);
|
|
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, limit, byU32, usingExtDict, dictSmall);
|
|
else
|
|
result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, usingExtDict, noDictIssue);
|
|
streamPtr->dictionary = (const BYTE*)source;
|
|
streamPtr->dictSize = (U32)inputSize;
|
|
streamPtr->currentOffset += (U32)inputSize;
|
|
return result;
|
|
}
|
|
}
|
|
|
|
|
|
int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize)
|
|
{
|
|
return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, 0, notLimited);
|
|
}
|
|
|
|
int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize)
|
|
{
|
|
return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput);
|
|
}
|
|
|
|
|
|
// Hidden debug function, to force separate 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);
|
|
|
|
streamPtr->dictionary = (const BYTE*)source;
|
|
streamPtr->dictSize = (U32)inputSize;
|
|
streamPtr->currentOffset += (U32)inputSize;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
int LZ4_saveDict (void* 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;
|
|
|
|
memcpy(safeBuffer, previousDictEnd - dictSize, dictSize);
|
|
|
|
dict->dictionary = (const BYTE*)safeBuffer;
|
|
dict->dictSize = (U32)dictSize;
|
|
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
/****************************
|
|
Decompression functions
|
|
****************************/
|
|
/*
|
|
* This generic decompression function cover all use cases.
|
|
* It shall be instanciated 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 optimisation.
|
|
*/
|
|
FORCE_INLINE int LZ4_decompress_generic(
|
|
const char* source,
|
|
char* 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 char* dictStart, /* only if dict==usingExtDict */
|
|
int dictSize /* note : = 0 if noDict */
|
|
)
|
|
{
|
|
/* Local Variables */
|
|
const BYTE* restrict ip = (const BYTE*) source;
|
|
const BYTE* ref;
|
|
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 = (const BYTE*)dest - dictSize;
|
|
|
|
const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize;
|
|
//#define OLD
|
|
#ifdef OLD
|
|
const size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; /* static reduces speed for LZ4_decompress_safe() on GCC64 */
|
|
#else
|
|
const size_t dec32table[] = {4-0, 4-3, 4-2, 4-3, 4-0, 4-0, 4-0, 4-0}; /* static reduces speed for LZ4_decompress_safe() on GCC64 */
|
|
#endif
|
|
static const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
|
|
|
|
const int checkOffset = (endOnInput) && (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;
|
|
|
|
/* get runlength */
|
|
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 ((sizeof(void*)==4) && unlikely(length>LZ4_MAX_INPUT_SIZE)) goto _output_error; /* overflow detection */
|
|
if ((sizeof(void*)==4) && unlikely((size_t)(op+length)<(size_t)(op))) goto _output_error; /* quickfix issue 134 */
|
|
if ((endOnInput) && (sizeof(void*)==4) && unlikely((size_t)(ip+length)<(size_t)(ip))) goto _output_error; /* quickfix issue 134 */
|
|
}
|
|
|
|
/* 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 -= (op-cpy); op = cpy;
|
|
|
|
/* get offset */
|
|
LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;
|
|
if ((checkOffset) && (unlikely(ref < lowLimit))) goto _output_error; /* Error : offset outside destination buffer */
|
|
|
|
/* get matchlength */
|
|
if ((length=(token&ML_MASK)) == ML_MASK)
|
|
{
|
|
unsigned s;
|
|
do
|
|
{
|
|
if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error;
|
|
s = *ip++;
|
|
length += s;
|
|
} while (s==255);
|
|
//if ((sizeof(void*)==4) && unlikely(length>LZ4_MAX_INPUT_SIZE)) goto _output_error; /* overflow detection */
|
|
if ((sizeof(void*)==4) && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* quickfix issue 134 */
|
|
}
|
|
|
|
/* check external dictionary */
|
|
if ((dict==usingExtDict) && (ref < (BYTE* const)dest))
|
|
{
|
|
if (unlikely(op+length+MINMATCH > oend-LASTLITERALS)) goto _output_error;
|
|
|
|
if (length+MINMATCH <= (size_t)(dest-(char*)ref))
|
|
{
|
|
ref = dictEnd - (dest-(char*)ref);
|
|
memcpy(op, ref, length+MINMATCH);
|
|
op += length+MINMATCH;
|
|
}
|
|
else
|
|
{
|
|
size_t copySize = (size_t)(dest-(char*)ref);
|
|
memcpy(op, dictEnd - copySize, copySize);
|
|
op += copySize;
|
|
copySize = length+MINMATCH - copySize;
|
|
if (copySize > (size_t)((char*)op-dest)) /* overlap */
|
|
{
|
|
BYTE* const cpy2 = op + copySize;
|
|
const BYTE* ref2 = (BYTE*)dest;
|
|
while (op < cpy2) *op++ = *ref2++;
|
|
}
|
|
else
|
|
{
|
|
memcpy(op, dest, copySize);
|
|
op += copySize;
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/* copy repeated sequence */
|
|
if (unlikely((op-ref)<(int)STEPSIZE))
|
|
{
|
|
const size_t dec64 = dec64table[(sizeof(void*)==4) ? 0 : op-ref];
|
|
op[0] = ref[0];
|
|
op[1] = ref[1];
|
|
op[2] = ref[2];
|
|
op[3] = ref[3];
|
|
#ifdef OLD
|
|
op += 4, ref += 4; ref -= dec32table[op-ref];
|
|
A32(op) = A32(ref);
|
|
op += STEPSIZE-4; ref -= dec64;
|
|
#else
|
|
ref += dec32table[op-ref];
|
|
A32(op+4) = A32(ref);
|
|
op += STEPSIZE; ref -= dec64;
|
|
#endif
|
|
} else { LZ4_COPYSTEP(op,ref); }
|
|
cpy = op + length - (STEPSIZE-4);
|
|
|
|
if (unlikely(cpy>oend-COPYLENGTH-(STEPSIZE-4)))
|
|
{
|
|
if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last 5 bytes must be literals */
|
|
if (op<oend-COPYLENGTH) LZ4_WILDCOPY(op, ref, (oend-COPYLENGTH));
|
|
while(op<cpy) *op++=*ref++;
|
|
op=cpy;
|
|
continue;
|
|
}
|
|
LZ4_WILDCOPY(op, ref, cpy);
|
|
op=cpy; /* correction */
|
|
}
|
|
|
|
/* end of decoding */
|
|
if (endOnInput)
|
|
return (int) (((char*)op)-dest); /* Nb of output bytes decoded */
|
|
else
|
|
return (int) (((char*)ip)-source); /* Nb of input bytes read */
|
|
|
|
/* Overflow error detected */
|
|
_output_error:
|
|
return (int) (-(((char*)ip)-source))-1;
|
|
}
|
|
|
|
|
|
int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxOutputSize)
|
|
{
|
|
return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, noDict, NULL, 0);
|
|
}
|
|
|
|
int LZ4_decompress_safe_partial(const char* source, char* dest, int compressedSize, int targetOutputSize, int maxOutputSize)
|
|
{
|
|
return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, partial, targetOutputSize, noDict, 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, NULL, 0);
|
|
}
|
|
|
|
/* streaming decompression functions */
|
|
|
|
//#define LZ4_STREAMDECODESIZE_U32 4
|
|
//#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U32 * sizeof(unsigned int))
|
|
//typedef struct { unsigned int table[LZ4_STREAMDECODESIZE_U32]; } LZ4_streamDecode_t;
|
|
typedef struct
|
|
{
|
|
const char* dictionary;
|
|
int dictSize;
|
|
} LZ4_streamDecode_t_internal;
|
|
|
|
/*
|
|
* If you prefer dynamic allocation methods,
|
|
* LZ4_createStreamDecode()
|
|
* provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure.
|
|
*/
|
|
void* LZ4_createStreamDecode()
|
|
{
|
|
void* lz4s = ALLOCATOR(sizeof(U32), LZ4_STREAMDECODESIZE_U32);
|
|
if (!lz4s) return NULL;
|
|
MEM_INIT(lz4s, 0, LZ4_STREAMDECODESIZE);
|
|
return lz4s;
|
|
}
|
|
|
|
/*
|
|
* LZ4_setDictDecode
|
|
* 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_setDictDecode (void* LZ4_streamDecode, const char* dictionary, int dictSize)
|
|
{
|
|
LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
|
|
lz4sd->dictionary = dictionary;
|
|
lz4sd->dictSize = dictSize;
|
|
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_setDictDecode()
|
|
*/
|
|
int LZ4_decompress_safe_continue (void* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize)
|
|
{
|
|
LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
|
|
int result;
|
|
|
|
result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize);
|
|
if (result <= 0) return result;
|
|
if (lz4sd->dictionary + lz4sd->dictSize == dest)
|
|
{
|
|
lz4sd->dictSize += result;
|
|
}
|
|
else
|
|
{
|
|
lz4sd->dictionary = dest;
|
|
lz4sd->dictSize = result;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
int LZ4_decompress_fast_continue (void* LZ4_streamDecode, const char* source, char* dest, int originalSize)
|
|
{
|
|
LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
|
|
int result;
|
|
|
|
result = LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize);
|
|
if (result <= 0) return result;
|
|
if (lz4sd->dictionary + lz4sd->dictSize == dest)
|
|
{
|
|
lz4sd->dictSize += result;
|
|
}
|
|
else
|
|
{
|
|
lz4sd->dictionary = dest;
|
|
lz4sd->dictSize = result;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
Advanced decoding functions :
|
|
*_usingDict() :
|
|
These decoding functions work the same as "_continue" ones,
|
|
the dictionary must be explicitly provided within parameters
|
|
*/
|
|
|
|
int LZ4_decompress_safe_usingDict(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, dictStart, dictSize);
|
|
}
|
|
|
|
int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize)
|
|
{
|
|
return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, dictStart, dictSize);
|
|
}
|
|
|
|
|
|
/***************************************************
|
|
Obsolete Functions
|
|
***************************************************/
|
|
/*
|
|
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; }
|
|
|
|
void LZ4_init(LZ4_stream_t_internal* lz4ds, const BYTE* base)
|
|
{
|
|
MEM_INIT(lz4ds, 0, LZ4_STREAMSIZE);
|
|
lz4ds->bufferStart = base;
|
|
}
|
|
|
|
int LZ4_resetStreamState(void* state, const 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, (const BYTE*)inputBuffer);
|
|
return 0;
|
|
}
|
|
|
|
void* LZ4_create (const char* inputBuffer)
|
|
{
|
|
void* lz4ds = ALLOCATOR(4, LZ4_STREAMSIZE_U32);
|
|
if (!lz4ds) return NULL;
|
|
LZ4_init ((LZ4_stream_t_internal*)lz4ds, (const BYTE*)inputBuffer);
|
|
return lz4ds;
|
|
}
|
|
|
|
char* LZ4_slideInputBuffer (void* LZ4_Data)
|
|
{
|
|
LZ4_stream_t_internal* lz4ds = (LZ4_stream_t_internal*)LZ4_Data;
|
|
|
|
LZ4_saveDict((LZ4_stream_t*)LZ4_Data, (char*)lz4ds->bufferStart, 64 KB);
|
|
|
|
return (char*)(lz4ds->bufferStart + 64 KB);
|
|
}
|
|
|
|
/* Obsolete compresson functions using User-allocated state */
|
|
|
|
int LZ4_sizeofState() { return LZ4_STREAMSIZE; }
|
|
|
|
int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize)
|
|
{
|
|
if (((size_t)(state)&3) != 0) return 0; /* Error : state is not aligned on 4-bytes boundary */
|
|
MEM_INIT(state, 0, LZ4_STREAMSIZE);
|
|
|
|
if (inputSize < (int)LZ4_64KLIMIT)
|
|
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue);
|
|
else
|
|
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue);
|
|
}
|
|
|
|
int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize)
|
|
{
|
|
if (((size_t)(state)&3) != 0) return 0; /* Error : state is not aligned on 4-bytes boundary */
|
|
MEM_INIT(state, 0, LZ4_STREAMSIZE);
|
|
|
|
if (inputSize < (int)LZ4_64KLIMIT)
|
|
return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue);
|
|
else
|
|
return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue);
|
|
}
|
|
|
|
/* 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, 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, NULL, 64 KB);
|
|
}
|