Upgrade LZ4 to hopefully fix wacky sporadic crash when built with g++ 5.3.1 on Debian/testing.

This commit is contained in:
Adam Ierymenko 2016-02-25 15:39:15 -08:00
parent e5f82f5457
commit 039790cf26
2 changed files with 525 additions and 332 deletions

View File

@ -34,7 +34,7 @@
/**************************************
Tuning parameters
* Tuning parameters
**************************************/
/*
* HEAPMODE :
@ -44,50 +44,15 @@
#define HEAPMODE 0
/*
* CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS :
* By default, the source code expects the compiler to correctly optimize
* 4-bytes and 8-bytes read on architectures able to handle it efficiently.
* This is not always the case. In some circumstances (ARM notably),
* the compiler will issue cautious code even when target is able to correctly handle unaligned memory accesses.
*
* You can force the compiler to use unaligned memory access by uncommenting the line below.
* One of the below scenarios will happen :
* 1 - Your target CPU correctly handle unaligned access, and was not well optimized by compiler (good case).
* You will witness large performance improvements (+50% and up).
* Keep the line uncommented and send a word to upstream (https://groups.google.com/forum/#!forum/lz4c)
* The goal is to automatically detect such situations by adding your target CPU within an exception list.
* 2 - Your target CPU correctly handle unaligned access, and was already already optimized by compiler
* No change will be experienced.
* 3 - Your target CPU inefficiently handle unaligned access.
* You will experience a performance loss. Comment back the line.
* 4 - Your target CPU does not handle unaligned access.
* Program will crash.
* If uncommenting results in better performance (case 1)
* please report your configuration to upstream (https://groups.google.com/forum/#!forum/lz4c)
* This way, an automatic detection macro can be added to match your case within later versions of the library.
* ACCELERATION_DEFAULT :
* Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
*/
/* #define CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS 1 */
#define ACCELERATION_DEFAULT 1
/**************************************
CPU Feature Detection
* CPU Feature Detection
**************************************/
/*
* Automated efficient unaligned memory access detection
* Based on known hardware architectures
* This list will be updated thanks to feedbacks
*/
#if defined(CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS) \
|| defined(__ARM_FEATURE_UNALIGNED) \
|| defined(__i386__) || defined(__x86_64__) \
|| defined(_M_IX86) || defined(_M_X64) \
|| defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_8__) \
|| (defined(_M_ARM) && (_M_ARM >= 7))
# define LZ4_UNALIGNED_ACCESS 1
#else
# define LZ4_UNALIGNED_ACCESS 0
#endif
/*
* LZ4_FORCE_SW_BITCOUNT
* Define this parameter if your target system or compiler does not support hardware bit count
@ -97,15 +62,15 @@
#endif
/**************************************
* Includes
**************************************/
#include "lz4.h"
/**************************************
* 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>
@ -113,7 +78,7 @@
# pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */
#else
# if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
# ifdef __GNUC__
# if defined(__GNUC__) || defined(__clang__)
# define FORCE_INLINE static inline __attribute__((always_inline))
# else
# define FORCE_INLINE static inline
@ -123,9 +88,8 @@
# endif /* __STDC_VERSION__ */
#endif /* _MSC_VER */
#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
/* 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)
@ -136,7 +100,7 @@
/**************************************
Memory routines
* Memory routines
**************************************/
#include <stdlib.h> /* malloc, calloc, free */
#define ALLOCATOR(n,s) calloc(n,s)
@ -146,13 +110,7 @@
/**************************************
Includes
**************************************/
#include "lz4.h"
/**************************************
Basic Types
* Basic Types
**************************************/
#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
# include <stdint.h>
@ -171,7 +129,7 @@
/**************************************
Reading and writing into memory
* Reading and writing into memory
**************************************/
#define STEPSIZE sizeof(size_t)
@ -184,10 +142,19 @@ static unsigned LZ4_isLittleEndian(void)
}
static U16 LZ4_read16(const void* memPtr)
{
U16 val16;
memcpy(&val16, memPtr, 2);
return val16;
}
static U16 LZ4_readLE16(const void* memPtr)
{
if ((LZ4_UNALIGNED_ACCESS) && (LZ4_isLittleEndian()))
return *(U16*)memPtr;
if (LZ4_isLittleEndian())
{
return LZ4_read16(memPtr);
}
else
{
const BYTE* p = (const BYTE*)memPtr;
@ -197,10 +164,9 @@ static U16 LZ4_readLE16(const void* memPtr)
static void LZ4_writeLE16(void* memPtr, U16 value)
{
if ((LZ4_UNALIGNED_ACCESS) && (LZ4_isLittleEndian()))
if (LZ4_isLittleEndian())
{
*(U16*)memPtr = value;
return;
memcpy(memPtr, &value, 2);
}
else
{
@ -210,41 +176,18 @@ static void LZ4_writeLE16(void* memPtr, U16 value)
}
}
static U16 LZ4_read16(const void* memPtr)
{
if (LZ4_UNALIGNED_ACCESS)
return *(U16*)memPtr;
else
{
U16 val16;
memcpy(&val16, memPtr, 2);
return val16;
}
}
static U32 LZ4_read32(const void* memPtr)
{
if (LZ4_UNALIGNED_ACCESS)
return *(U32*)memPtr;
else
{
U32 val32;
memcpy(&val32, memPtr, 4);
return val32;
}
U32 val32;
memcpy(&val32, memPtr, 4);
return val32;
}
static U64 LZ4_read64(const void* memPtr)
{
if (LZ4_UNALIGNED_ACCESS)
return *(U64*)memPtr;
else
{
U64 val64;
memcpy(&val64, memPtr, 8);
return val64;
}
U64 val64;
memcpy(&val64, memPtr, 8);
return val64;
}
static size_t LZ4_read_ARCH(const void* p)
@ -256,31 +199,9 @@ static size_t LZ4_read_ARCH(const void* p)
}
static void LZ4_copy4(void* dstPtr, const void* srcPtr)
{
if (LZ4_UNALIGNED_ACCESS)
{
*(U32*)dstPtr = *(U32*)srcPtr;
return;
}
memcpy(dstPtr, srcPtr, 4);
}
static void LZ4_copy4(void* dstPtr, const void* srcPtr) { memcpy(dstPtr, srcPtr, 4); }
static void LZ4_copy8(void* dstPtr, const void* srcPtr)
{
#if GCC_VERSION!=409 /* disabled on GCC 4.9, as it generates invalid opcode (crash) */
if (LZ4_UNALIGNED_ACCESS)
{
if (LZ4_64bits())
*(U64*)dstPtr = *(U64*)srcPtr;
else
((U32*)dstPtr)[0] = ((U32*)srcPtr)[0],
((U32*)dstPtr)[1] = ((U32*)srcPtr)[1];
return;
}
#endif
memcpy(dstPtr, srcPtr, 8);
}
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)
@ -293,7 +214,7 @@ static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
/**************************************
Common Constants
* Common Constants
**************************************/
#define MINMATCH 4
@ -334,7 +255,7 @@ static unsigned LZ4_NbCommonBytes (register size_t val)
unsigned long r = 0;
_BitScanForward64( &r, (U64)val );
return (int)(r>>3);
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
# 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 };
@ -347,7 +268,7 @@ static unsigned LZ4_NbCommonBytes (register size_t val)
unsigned long r;
_BitScanForward( &r, (U32)val );
return (int)(r>>3);
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
# 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 };
@ -363,8 +284,8 @@ static unsigned LZ4_NbCommonBytes (register size_t val)
unsigned long r = 0;
_BitScanReverse64( &r, val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
return (__builtin_clzll(val) >> 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; }
@ -379,8 +300,8 @@ static unsigned LZ4_NbCommonBytes (register size_t val)
unsigned long r = 0;
_BitScanReverse( &r, (unsigned long)val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
return (__builtin_clz(val) >> 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; }
@ -422,13 +343,6 @@ 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 Utils
**************************************/
int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; }
int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
/**************************************
* Local Structures and types
**************************************/
@ -437,7 +351,7 @@ typedef struct {
U32 currentOffset;
U32 initCheck;
const BYTE* dictionary;
const BYTE* bufferStart;
BYTE* bufferStart; /* obsolete, used for slideInputBuffer */
U32 dictSize;
} LZ4_stream_t_internal;
@ -451,6 +365,14 @@ 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
@ -464,7 +386,22 @@ static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType)
return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
}
static U32 LZ4_hashPosition(const BYTE* p, tableType_t tableType) { return LZ4_hashSequence(LZ4_read32(p), tableType); }
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)
{
@ -495,16 +432,17 @@ static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t t
return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
}
static int LZ4_compress_generic(
void* ctx,
const char* source,
char* dest,
int inputSize,
int maxOutputSize,
limitedOutput_directive outputLimited,
tableType_t const tableType,
dict_directive dict,
dictIssue_directive dictIssue)
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;
@ -527,7 +465,7 @@ static int LZ4_compress_generic(
size_t refDelta=0;
/* Init conditions */
if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
switch(dict)
{
case noDict:
@ -558,15 +496,15 @@ static int LZ4_compress_generic(
BYTE* token;
{
const BYTE* forwardIp = ip;
unsigned step=1;
unsigned searchMatchNb = (1U << LZ4_skipTrigger);
unsigned step = 1;
unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
/* Find a match */
do {
U32 h = forwardH;
ip = forwardIp;
forwardIp += step;
step = searchMatchNb++ >> LZ4_skipTrigger;
step = (searchMatchNb++ >> LZ4_skipTrigger);
if (unlikely(forwardIp > mflimit)) goto _last_literals;
@ -693,13 +631,22 @@ _next_match:
_last_literals:
/* Encode Last Literals */
{
int lastRun = (int)(iend - anchor);
if ((outputLimited) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize))
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>=(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;
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 */
@ -707,39 +654,271 @@ _last_literals:
}
int LZ4_compress(const char* source, char* dest, int inputSize)
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* ctx = ALLOCATOR(LZ4_STREAMSIZE_U64, 8); /* Aligned on 8-bytes boundaries */
void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
#else
U64 ctx[LZ4_STREAMSIZE_U64] = {0}; /* Ensure data is aligned on 8-bytes boundaries */
LZ4_stream_t ctx;
void* ctxPtr = &ctx;
#endif
int result;
if (inputSize < 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, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue);
int result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
#if (HEAPMODE)
FREEMEM(ctx);
FREEMEM(ctxPtr);
#endif
return result;
}
int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
int LZ4_compress_default(const char* source, char* dest, int inputSize, int maxOutputSize)
{
#if (HEAPMODE)
void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U64, 8); /* Aligned on 8-bytes boundaries */
#else
U64 ctx[LZ4_STREAMSIZE_U64] = {0}; /* Ensure data is aligned on 8-bytes boundaries */
#endif
int result;
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)
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue);
return LZ4_compress_generic(&ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
else
result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue);
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);
@ -748,19 +927,10 @@ int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, in
}
/*****************************************
* Experimental : Streaming functions
*****************************************/
/*
* LZ4_initStream
* Use this function once, to init a newly allocated LZ4_stream_t structure
* Return : 1 if OK, 0 if error
*/
void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
{
MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
}
/********************************
* Streaming functions
********************************/
LZ4_stream_t* LZ4_createStream(void)
{
@ -770,6 +940,11 @@ LZ4_stream_t* LZ4_createStream(void)
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);
@ -777,6 +952,7 @@ int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
}
#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;
@ -784,24 +960,26 @@ int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
const BYTE* const dictEnd = p + dictSize;
const BYTE* base;
if (dict->initCheck) LZ4_resetStream(LZ4_dict); /* Uninitialized structure detected */
if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized structure, or reuse overflow */
LZ4_resetStream(LZ4_dict);
if (dictSize < MINMATCH)
if (dictSize < (int)HASH_UNIT)
{
dict->dictionary = NULL;
dict->dictSize = 0;
return 0;
}
if (p <= dictEnd - 64 KB) p = dictEnd - 64 KB;
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-MINMATCH)
while (p <= dictEnd-HASH_UNIT)
{
LZ4_putPosition(p, dict, byU32, base);
LZ4_putPosition(p, dict->hashTable, byU32, base);
p+=3;
}
@ -830,8 +1008,7 @@ static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
}
FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* source, char* dest, int inputSize,
int maxOutputSize, limitedOutput_directive limit)
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;
@ -840,6 +1017,7 @@ FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* so
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 */
{
@ -858,9 +1036,9 @@ FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* so
{
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);
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, limit, byU32, withPrefix64k, noDictIssue);
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;
@ -870,9 +1048,9 @@ FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* so
{
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);
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, limit, byU32, usingExtDict, noDictIssue);
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;
@ -880,18 +1058,8 @@ FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* so
}
}
int LZ4_compress_continue (LZ4_stream_t* 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 (LZ4_stream_t* 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 */
/* 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;
@ -902,7 +1070,7 @@ int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char*
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);
result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
streamPtr->dictionary = (const BYTE*)source;
streamPtr->dictSize = (U32)inputSize;
@ -955,7 +1123,7 @@ FORCE_INLINE int LZ4_decompress_generic(
)
{
/* Local Variables */
const BYTE* restrict ip = (const BYTE*) source;
const BYTE* ip = (const BYTE*) source;
const BYTE* const iend = ip + inputSize;
BYTE* op = (BYTE*) dest;
@ -1051,8 +1219,7 @@ FORCE_INLINE int LZ4_decompress_generic(
{
/* match can be copied as a single segment from external dictionary */
match = dictEnd - (lowPrefix-match);
memcpy(op, match, length);
op += length;
memmove(op, match, length); op += length;
}
else
{
@ -1110,11 +1277,11 @@ FORCE_INLINE int LZ4_decompress_generic(
if (endOnInput)
return (int) (((char*)op)-dest); /* Nb of output bytes decoded */
else
return (int) (((char*)ip)-source); /* Nb of input bytes read */
return (int) (((const char*)ip)-source); /* Nb of input bytes read */
/* Overflow error detected */
_output_error:
return (int) (-(((char*)ip)-source))-1;
return (int) (-(((const char*)ip)-source))-1;
}
@ -1138,9 +1305,9 @@ int LZ4_decompress_fast(const char* source, char* dest, int originalSize)
typedef struct
{
BYTE* externalDict;
const BYTE* externalDict;
size_t extDictSize;
BYTE* prefixEnd;
const BYTE* prefixEnd;
size_t prefixSize;
} LZ4_streamDecode_t_internal;
@ -1172,7 +1339,7 @@ int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dicti
{
LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
lz4sd->prefixSize = (size_t) dictSize;
lz4sd->prefixEnd = (BYTE*) dictionary + dictSize;
lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize;
lz4sd->externalDict = NULL;
lz4sd->extDictSize = 0;
return 1;
@ -1261,7 +1428,7 @@ FORCE_INLINE int LZ4_decompress_usingDict_generic(const char* source, char* dest
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, (BYTE*)dictStart, dictSize);
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)
@ -1277,13 +1444,21 @@ int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSi
/* 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, (BYTE*)dictStart, 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.
@ -1298,23 +1473,23 @@ int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize,
int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; }
static void LZ4_init(LZ4_stream_t_internal* lz4ds, const BYTE* base)
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, const char* inputBuffer)
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, (const BYTE*)inputBuffer);
LZ4_init((LZ4_stream_t_internal*)state, (BYTE*)inputBuffer);
return 0;
}
void* LZ4_create (const char* inputBuffer)
void* LZ4_create (char* inputBuffer)
{
void* lz4ds = ALLOCATOR(8, LZ4_STREAMSIZE_U64);
LZ4_init ((LZ4_stream_t_internal*)lz4ds, (const BYTE*)inputBuffer);
LZ4_init ((LZ4_stream_t_internal*)lz4ds, (BYTE*)inputBuffer);
return lz4ds;
}
@ -1325,32 +1500,6 @@ char* LZ4_slideInputBuffer (void* LZ4_Data)
return (char*)(ctx->bufferStart + dictSize);
}
/* 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 < 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, LZ4_64bits() ? 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 < 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, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue);
}
/* Obsolete streaming decompression functions */
int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize)

View File

@ -39,17 +39,17 @@ extern "C" {
#endif
/*
* lz4.h provides block compression functions, for optimal performance.
* lz4.h provides block compression functions, and gives full buffer control to programmer.
* If you need to generate inter-operable compressed data (respecting LZ4 frame specification),
* please use lz4frame.h instead.
* and can let the library handle its own memory, please use lz4frame.h instead.
*/
/**************************************
* Version
**************************************/
#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
#define LZ4_VERSION_MINOR 6 /* for new (non-breaking) interface capabilities */
#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */
#define LZ4_VERSION_MINOR 7 /* for new (non-breaking) interface capabilities */
#define LZ4_VERSION_RELEASE 1 /* for tweaks, bug-fixes, or development */
#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
int LZ4_versionNumber (void);
@ -70,28 +70,32 @@ int LZ4_versionNumber (void);
* Simple Functions
**************************************/
int LZ4_compress (const char* source, char* dest, int sourceSize);
int LZ4_compress_default(const char* source, char* dest, int sourceSize, int maxDestSize);
int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxDecompressedSize);
/*
LZ4_compress() :
Compresses 'sourceSize' bytes from 'source' into 'dest'.
Destination buffer must be already allocated,
and must be sized to handle worst cases situations (input data not compressible)
Worst case size evaluation is provided by function LZ4_compressBound()
inputSize : Max supported value is LZ4_MAX_INPUT_SIZE
return : the number of bytes written in buffer dest
or 0 if the compression fails
LZ4_compress_default() :
Compresses 'sourceSize' bytes from buffer 'source'
into already allocated 'dest' buffer of size 'maxDestSize'.
Compression is guaranteed to succeed if 'maxDestSize' >= LZ4_compressBound(sourceSize).
It also runs faster, so it's a recommended setting.
If the function cannot compress 'source' into a more limited 'dest' budget,
compression stops *immediately*, and the function result is zero.
As a consequence, 'dest' content is not valid.
This function never writes outside 'dest' buffer, nor read outside 'source' buffer.
sourceSize : Max supported value is LZ4_MAX_INPUT_VALUE
maxDestSize : full or partial size of buffer 'dest' (which must be already allocated)
return : the number of bytes written into buffer 'dest' (necessarily <= maxOutputSize)
or 0 if compression fails
LZ4_decompress_safe() :
compressedSize : is obviously the source size
maxDecompressedSize : is the size of the destination buffer, which must be already allocated.
return : the number of bytes decompressed into the destination buffer (necessarily <= maxDecompressedSize)
If the destination buffer is not large enough, decoding will stop and output an error code (<0).
compressedSize : is the precise full size of the compressed block.
maxDecompressedSize : is the size of destination buffer, which must be already allocated.
return : the number of bytes decompressed into destination buffer (necessarily <= maxDecompressedSize)
If destination buffer is not large enough, decoding will stop and output an error code (<0).
If the source stream is detected malformed, the function will stop decoding and return a negative result.
This function is protected against buffer overflow exploits,
and never writes outside of output buffer, nor reads outside of input buffer.
It is also protected against malicious data packets.
This function is protected against buffer overflow exploits, including malicious data packets.
It never writes outside output buffer, nor reads outside input buffer.
*/
@ -99,45 +103,54 @@ LZ4_decompress_safe() :
* Advanced Functions
**************************************/
#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
#define LZ4_COMPRESSBOUND(isize) ((unsigned int)(isize) > (unsigned int)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
/*
LZ4_compressBound() :
Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
This function is primarily useful for memory allocation purposes (output buffer size).
This function is primarily useful for memory allocation purposes (destination buffer size).
Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
isize : is the input size. Max supported value is LZ4_MAX_INPUT_SIZE
return : maximum output size in a "worst case" scenario
or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE)
Note that LZ4_compress_default() compress faster when dest buffer size is >= LZ4_compressBound(srcSize)
inputSize : max supported value is LZ4_MAX_INPUT_SIZE
return : maximum output size in a "worst case" scenario
or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE)
*/
int LZ4_compressBound(int isize);
int LZ4_compressBound(int inputSize);
/*
LZ4_compress_fast() :
Same as LZ4_compress_default(), but allows to select an "acceleration" factor.
The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
An acceleration value of "1" is the same as regular LZ4_compress_default()
Values <= 0 will be replaced by ACCELERATION_DEFAULT (see lz4.c), which is 1.
*/
int LZ4_compress_fast (const char* source, char* dest, int sourceSize, int maxDestSize, int acceleration);
/*
LZ4_compress_limitedOutput() :
Compress 'sourceSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'.
If it cannot achieve it, compression will stop, and result of the function will be zero.
This saves time and memory on detecting non-compressible (or barely compressible) data.
This function never writes outside of provided output buffer.
sourceSize : Max supported value is LZ4_MAX_INPUT_VALUE
maxOutputSize : is the size of the destination buffer (which must be already allocated)
return : the number of bytes written in buffer 'dest'
or 0 if compression fails
*/
int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
/*
LZ4_compress_withState() :
Same compression functions, but using an externally allocated memory space to store compression state.
LZ4_compress_fast_extState() :
Same compression function, just using an externally allocated memory space to store compression state.
Use LZ4_sizeofState() to know how much memory must be allocated,
and then, provide it as 'void* state' to compression functions.
and allocate it on 8-bytes boundaries (using malloc() typically).
Then, provide it as 'void* state' to compression function.
*/
int LZ4_sizeofState(void);
int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
int LZ4_compress_fast_extState (void* state, const char* source, char* dest, int inputSize, int maxDestSize, int acceleration);
/*
LZ4_compress_destSize() :
Reverse the logic, by compressing as much data as possible from 'source' buffer
into already allocated buffer 'dest' of size 'targetDestSize'.
This function either compresses the entire 'source' content into 'dest' if it's large enough,
or fill 'dest' buffer completely with as much data as possible from 'source'.
*sourceSizePtr : will be modified to indicate how many bytes where read from 'source' to fill 'dest'.
New value is necessarily <= old value.
return : Nb bytes written into 'dest' (necessarily <= targetDestSize)
or 0 if compression fails
*/
int LZ4_compress_destSize (const char* source, char* dest, int* sourceSizePtr, int targetDestSize);
/*
@ -153,7 +166,6 @@ LZ4_decompress_fast() :
*/
int LZ4_decompress_fast (const char* source, char* dest, int originalSize);
/*
LZ4_decompress_safe_partial() :
This function decompress a compressed block of size 'compressedSize' at position 'source'
@ -172,7 +184,6 @@ int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedS
/***********************************************
* Streaming Compression Functions
***********************************************/
#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4)
#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(long long))
/*
@ -188,7 +199,7 @@ typedef struct { long long table[LZ4_STREAMSIZE_U64]; } LZ4_stream_t;
* LZ4_resetStream
* Use this function to init an allocated LZ4_stream_t structure
*/
void LZ4_resetStream (LZ4_stream_t* LZ4_streamPtr);
void LZ4_resetStream (LZ4_stream_t* streamPtr);
/*
* LZ4_createStream will allocate and initialize an LZ4_stream_t structure
@ -197,7 +208,7 @@ void LZ4_resetStream (LZ4_stream_t* LZ4_streamPtr);
* They are more future proof, in case of a change of LZ4_stream_t size.
*/
LZ4_stream_t* LZ4_createStream(void);
int LZ4_freeStream (LZ4_stream_t* LZ4_streamPtr);
int LZ4_freeStream (LZ4_stream_t* streamPtr);
/*
* LZ4_loadDict
@ -206,32 +217,27 @@ int LZ4_freeStream (LZ4_stream_t* LZ4_streamPtr);
* Loading a size of 0 is allowed.
* Return : dictionary size, in bytes (necessarily <= 64 KB)
*/
int LZ4_loadDict (LZ4_stream_t* LZ4_streamPtr, const char* dictionary, int dictSize);
int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
/*
* LZ4_compress_continue
* Compress data block 'source', using blocks compressed before as dictionary to improve compression ratio
* Previous data blocks are assumed to still be present at their previous location.
* dest buffer must be already allocated, and sized to at least LZ4_compressBound(inputSize)
* LZ4_compress_fast_continue
* Compress buffer content 'src', using data from previously compressed blocks as dictionary to improve compression ratio.
* Important : Previous data blocks are assumed to still be present and unmodified !
* 'dst' buffer must be already allocated.
* If maxDstSize >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
* If not, and if compressed data cannot fit into 'dst' buffer size, compression stops, and function returns a zero.
*/
int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
/*
* LZ4_compress_limitedOutput_continue
* Same as before, but also specify a maximum target compressed size (maxOutputSize)
* If objective cannot be met, compression exits, and returns a zero.
*/
int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int maxDstSize, int acceleration);
/*
* LZ4_saveDict
* If previously compressed data block is not guaranteed to remain available at its memory location
* save it into a safer place (char* safeBuffer)
* Note : you don't need to call LZ4_loadDict() afterwards,
* dictionary is immediately usable, you can therefore call again LZ4_compress_continue()
* dictionary is immediately usable, you can therefore call LZ4_compress_fast_continue()
* Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error
*/
int LZ4_saveDict (LZ4_stream_t* LZ4_streamPtr, char* safeBuffer, int dictSize);
int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize);
/************************************************
@ -266,8 +272,18 @@ int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dicti
*_continue() :
These decoding functions allow decompression of multiple blocks in "streaming" mode.
Previously decoded blocks *must* remain available at the memory position where they were decoded (up to 64 KB)
If this condition is not possible, save the relevant part of decoded data into a safe buffer,
and indicate where is its new address using LZ4_setStreamDecode()
In the case of a ring buffers, decoding buffer must be either :
- Exactly same size as encoding buffer, with same update rule (block boundaries at same positions)
In which case, the decoding & encoding ring buffer can have any size, including very small ones ( < 64 KB).
- Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
maxBlockSize is implementation dependent. It's the maximum size you intend to compress into a single block.
In which case, encoding and decoding buffers do not need to be synchronized,
and encoding ring buffer can have any size, including small ones ( < 64 KB).
- _At least_ 64 KB + 8 bytes + maxBlockSize.
In which case, encoding and decoding buffers do not need to be synchronized,
and encoding ring buffer can have any size, including larger than decoding buffer.
Whenever these conditions are not possible, save the last 64KB of decoded data into a safe buffer,
and indicate where it is saved using LZ4_setStreamDecode()
*/
int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxDecompressedSize);
int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize);
@ -277,8 +293,8 @@ int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const ch
Advanced decoding functions :
*_usingDict() :
These decoding functions work the same as
a combination of LZ4_setDictDecode() followed by LZ4_decompress_x_continue()
They are stand-alone and don't use nor update an LZ4_streamDecode_t structure.
a combination of LZ4_setStreamDecode() followed by LZ4_decompress_x_continue()
They are stand-alone. They don't need nor update an LZ4_streamDecode_t structure.
*/
int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxDecompressedSize, const char* dictStart, int dictSize);
int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize);
@ -288,27 +304,55 @@ int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalS
/**************************************
* Obsolete Functions
**************************************/
/*
Obsolete decompression 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 the same as LZ4_decompress_fast
- LZ4_uncompress_unknownOutputSize is the same as LZ4_decompress_safe
These function prototypes are now disabled; uncomment them if you really need them.
It is highly recommended to stop using these functions and migrate to newer ones */
/* Deprecate Warnings */
/* Should these warnings messages be a problem,
it is generally possible to disable them,
with -Wno-deprecated-declarations for gcc
or _CRT_SECURE_NO_WARNINGS in Visual for example.
You can also define LZ4_DEPRECATE_WARNING_DEFBLOCK. */
#ifndef LZ4_DEPRECATE_WARNING_DEFBLOCK
# define LZ4_DEPRECATE_WARNING_DEFBLOCK
# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
# if (LZ4_GCC_VERSION >= 405) || defined(__clang__)
# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
# elif (LZ4_GCC_VERSION >= 301)
# define LZ4_DEPRECATED(message) __attribute__((deprecated))
# elif defined(_MSC_VER)
# define LZ4_DEPRECATED(message) __declspec(deprecated(message))
# else
# pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler")
# define LZ4_DEPRECATED(message)
# endif
#endif /* LZ4_DEPRECATE_WARNING_DEFBLOCK */
/* Obsolete compression functions */
/* These functions are planned to start generate warnings by r131 approximately */
int LZ4_compress (const char* source, char* dest, int sourceSize);
int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
/* Obsolete decompression functions */
/* These function names are completely deprecated and must no longer be used.
They are only provided here for compatibility with older programs.
- LZ4_uncompress is the same as LZ4_decompress_fast
- LZ4_uncompress_unknownOutputSize is the same as LZ4_decompress_safe
These function prototypes are now disabled; uncomment them only if you really need them.
It is highly recommended to stop using these prototypes and migrate to maintained ones */
/* int LZ4_uncompress (const char* source, char* dest, int outputSize); */
/* int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize); */
/* Obsolete streaming functions; use new streaming interface whenever possible */
void* LZ4_create (const char* inputBuffer);
int LZ4_sizeofStreamState(void);
int LZ4_resetStreamState(void* state, const char* inputBuffer);
char* LZ4_slideInputBuffer (void* state);
LZ4_DEPRECATED("use LZ4_createStream() instead") void* LZ4_create (char* inputBuffer);
LZ4_DEPRECATED("use LZ4_createStream() instead") int LZ4_sizeofStreamState(void);
LZ4_DEPRECATED("use LZ4_resetStream() instead") int LZ4_resetStreamState(void* state, char* inputBuffer);
LZ4_DEPRECATED("use LZ4_saveDict() instead") char* LZ4_slideInputBuffer (void* state);
/* Obsolete streaming decoding functions */
int LZ4_decompress_safe_withPrefix64k (const char* source, char* dest, int compressedSize, int maxOutputSize);
int LZ4_decompress_fast_withPrefix64k (const char* source, char* dest, int originalSize);
LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
#if defined (__cplusplus)