Take upstream release from https://github.com/Cyan4973/lz4/releases,
copy lz4-r131/lib/lz4.c to src/compat/compat-lz4.c
copy lz4-r131/lib/lz4.h to src/compat/compat-lz4.h
change #include line in compat-lz4.c to use "compat-lz4.h" not "lz4.h"
No other changes to upstream code.
This commit is quite huge, but this is because we bundled a fairly old
version and upstream refactored quite a lot of code, changed // comments
to /* */ style, etc - to review, compare compat-lz4.* files to upstream.
Signed-off-by: Gert Doering <g...@greenie.muc.de>
---
src/compat/compat-lz4.c | 1710 +++++++++++++++++++++++++++++++++--------------
src/compat/compat-lz4.h | 375 ++++++++---
2 files changed, 1463 insertions(+), 622 deletions(-)
diff --git a/src/compat/compat-lz4.c b/src/compat/compat-lz4.c
index c63c18b..b15c90a 100644
--- a/src/compat/compat-lz4.c
+++ b/src/compat/compat-lz4.c
@@ -1,6 +1,7 @@
/*
LZ4 - Fast LZ compression algorithm
- Copyright (C) 2011-2013, Yann Collet.
+ Copyright (C) 2011-2015, Yann Collet.
+
BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
Redistribution and use in source and binary forms, with or without
@@ -27,121 +28,68 @@
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 source repository : https://github.com/Cyan4973/lz4
- LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
*/
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#elif defined(_MSC_VER)
-#include "config-msvc.h"
-#endif
-#ifdef NEED_COMPAT_LZ4
-
-//**************************************
-// Tuning parameters
-//**************************************
-// MEMORY_USAGE :
-// Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16
-> 64KB; 20 -> 1MB; etc.)
-// Increasing memory usage improves compression ratio
-// Reduced memory usage can improve speed, due to cache effect
-// Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
-#define MEMORY_USAGE 14
-
-// 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)).
+/**************************************
+* Tuning parameters
+**************************************/
+/*
+ * HEAPMODE :
+ * Select how default compression functions will allocate memory for their
hash table,
+ * in memory stack (0:default, fastest), or in memory heap (1:requires
malloc()).
+ */
#define HEAPMODE 0
+/*
+ * ACCELERATION_DEFAULT :
+ * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
+ */
+#define ACCELERATION_DEFAULT 1
-//**************************************
-// CPU Feature Detection
-//**************************************
-// 32 or 64 bits ?
-#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \
- || defined(__powerpc64__) || defined(__ppc64__) || defined(__PPC64__) \
- || defined(__64BIT__) || defined(_LP64) || defined(__LP64__) \
- || 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
-#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
+/**************************************
+* CPU Feature Detection
+**************************************/
+/*
+ * LZ4_FORCE_SW_BITCOUNT
+ * Define this parameter if your target system or compiler does not support
hardware bit count
+ */
+#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE
does not support Hardware bit count */
# define LZ4_FORCE_SW_BITCOUNT
#endif
-// 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
+/**************************************
+* Includes
+**************************************/
+#include "compat-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
+/**************************************
+* Compiler Options
+**************************************/
+#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
+# include <intrin.h>
+# pragma warning(disable : 4127) /* disable: C4127: conditional
expression is constant */
+# pragma warning(disable : 4293) /* disable: C4293: too large shift
(32-bits) */
#else
-# ifdef __GNUC__
-# define FORCE_INLINE static inline __attribute__((always_inline))
+# if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
+# if defined(__GNUC__) || defined(__clang__)
+# define FORCE_INLINE static inline __attribute__((always_inline))
+# else
+# define FORCE_INLINE static inline
+# endif
# else
-# define FORCE_INLINE static inline
-# endif
-#endif
-
-#ifdef _MSC_VER
-# define lz4_bswap16(x) _byteswap_ushort(x)
-#else
-# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) &
0xffu) << 8)))
-#endif
+# define FORCE_INLINE static
+# 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)
@@ -151,26 +99,20 @@
#define unlikely(expr) expect((expr) != 0, 0)
-//**************************************
-// Memory routines
-//**************************************
-#include <stdlib.h> // malloc, calloc, free
+/**************************************
+* Memory routines
+**************************************/
+#include <stdlib.h> /* malloc, calloc, free */
#define ALLOCATOR(n,s) calloc(n,s)
#define FREEMEM free
-#include <string.h> // memset, memcpy
+#include <string.h> /* memset, memcpy */
#define MEM_INIT memset
-//**************************************
-// Includes
-//**************************************
-#include "compat-lz4.h"
-
-
-//**************************************
-// Basic Types
-//**************************************
-#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L // C99
+/**************************************
+* Basic Types
+**************************************/
+#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
# include <stdint.h>
typedef uint8_t BYTE;
typedef uint16_t U16;
@@ -185,55 +127,105 @@
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
+/**************************************
+* Reading and writing into memory
+**************************************/
+#define STEPSIZE sizeof(size_t)
-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;
+static unsigned LZ4_64bits(void) { return sizeof(void*)==8; }
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
-# if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
-# pragma pack(0)
-# else
-# pragma pack(pop)
-# endif
-#endif
+static unsigned LZ4_isLittleEndian(void)
+{
+ const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static :
performance detrimental */
+ return one.c[0];
+}
+
+
+static U16 LZ4_read16(const void* memPtr)
+{
+ U16 val16;
+ memcpy(&val16, memPtr, 2);
+ return val16;
+}
+
+static U16 LZ4_readLE16(const void* memPtr)
+{
+ if (LZ4_isLittleEndian())
+ {
+ return LZ4_read16(memPtr);
+ }
+ else
+ {
+ const BYTE* p = (const BYTE*)memPtr;
+ return (U16)((U16)p[0] + (p[1]<<8));
+ }
+}
+
+static void LZ4_writeLE16(void* memPtr, U16 value)
+{
+ if (LZ4_isLittleEndian())
+ {
+ memcpy(memPtr, &value, 2);
+ }
+ else
+ {
+ BYTE* p = (BYTE*)memPtr;
+ p[0] = (BYTE) value;
+ p[1] = (BYTE)(value>>8);
+ }
+}
-#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)
+static U32 LZ4_read32(const void* memPtr)
+{
+ U32 val32;
+ memcpy(&val32, memPtr, 4);
+ return val32;
+}
+static U64 LZ4_read64(const void* memPtr)
+{
+ U64 val64;
+ memcpy(&val64, memPtr, 8);
+ return val64;
+}
-//**************************************
-// Constants
-//**************************************
-#define LZ4_HASHLOG (MEMORY_USAGE-2)
-#define HASHTABLESIZE (1 << MEMORY_USAGE)
-#define HASHNBCELLS4 (1 << LZ4_HASHLOG)
+static size_t LZ4_read_ARCH(const void* p)
+{
+ if (LZ4_64bits())
+ return (size_t)LZ4_read64(p);
+ else
+ return (size_t)LZ4_read32(p);
+}
+
+
+static void LZ4_copy4(void* dstPtr, const void* srcPtr) { memcpy(dstPtr,
srcPtr, 4); }
+static void LZ4_copy8(void* dstPtr, const void* srcPtr) { memcpy(dstPtr,
srcPtr, 8); }
+
+/* customized version of memcpy, which may overwrite up to 7 bytes beyond
dstEnd */
+static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
+{
+ BYTE* d = (BYTE*)dstPtr;
+ const BYTE* s = (const BYTE*)srcPtr;
+ BYTE* e = (BYTE*)dstEnd;
+ do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e);
+}
+
+
+/**************************************
+* Common Constants
+**************************************/
#define MINMATCH 4
#define COPYLENGTH 8
#define LASTLITERALS 5
#define MFLIMIT (COPYLENGTH+MINMATCH)
-const int LZ4_minLength = (MFLIMIT+1);
+static const int LZ4_minLength = (MFLIMIT+1);
-#define LZ4_64KLIMIT ((1<<16) + (MFLIMIT-1))
-#define SKIPSTRENGTH 6 // Increasing this value will make the compression
run slower on incompressible data
+#define KB *(1 <<10)
+#define MB *(1 <<20)
+#define GB *(1U<<30)
#define MAXD_LOG 16
#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
@@ -243,135 +235,150 @@ const int LZ4_minLength = (MFLIMIT+1);
#define RUN_BITS (8-ML_BITS)
#define RUN_MASK ((1U<<RUN_BITS)-1)
-#define KB *(1U<<10)
-#define MB *(1U<<20)
-#define GB *(1U<<30)
+/**************************************
+* Common Utils
+**************************************/
+#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) };
} /* use only *after* variable declarations */
-//**************************************
-// Structures and local types
-//**************************************
-typedef struct {
- U32 hashTable[HASHNBCELLS4];
- const BYTE* bufferStart;
- const BYTE* base;
- const BYTE* nextBlock;
-} LZ4_Data_Structure;
+/**************************************
+* Common functions
+**************************************/
+static unsigned LZ4_NbCommonBytes (register size_t val)
+{
+ if (LZ4_isLittleEndian())
+ {
+ if (LZ4_64bits())
+ {
+# if defined(_MSC_VER) && defined(_WIN64) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanForward64( &r, (U64)val );
+ return (int)(r>>3);
+# elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_ctzll((U64)val) >> 3);
+# else
+ static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2,
0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0,
1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5,
7, 6, 7, 7 };
+ return DeBruijnBytePos[((U64)((val & -(long long)val) *
0x0218A392CDABBD3FULL)) >> 58];
+# endif
+ }
+ else /* 32 bits */
+ {
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r;
+ _BitScanForward( &r, (U32)val );
+ return (int)(r>>3);
+# elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_ctz((U32)val) >> 3);
+# else
+ static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0,
3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
+ return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >>
27];
+# endif
+ }
+ }
+ else /* Big Endian CPU */
+ {
+ if (LZ4_64bits())
+ {
+# if defined(_MSC_VER) && defined(_WIN64) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanReverse64( &r, val );
+ return (unsigned)(r>>3);
+# elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_clzll((U64)val) >> 3);
+# else
+ unsigned r;
+ if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
+ if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
+ r += (!val);
+ return r;
+# endif
+ }
+ else /* 32 bits */
+ {
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanReverse( &r, (unsigned long)val );
+ return (unsigned)(r>>3);
+# elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) &&
!defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_clz((U32)val) >> 3);
+# else
+ unsigned r;
+ if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
+ r += (!val);
+ return r;
+# endif
+ }
+ }
+}
-typedef enum { notLimited = 0, limited = 1 } limitedOutput_directive;
-typedef enum { byPtr, byU32, byU16 } tableType_t;
+static unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE*
pInLimit)
+{
+ const BYTE* const pStart = pIn;
-typedef enum { noPrefix = 0, withPrefix = 1 } prefix64k_directive;
+ while (likely(pIn<pInLimit-(STEPSIZE-1)))
+ {
+ size_t diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+ if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; }
+ pIn += LZ4_NbCommonBytes(diff);
+ return (unsigned)(pIn - pStart);
+ }
-typedef enum { endOnOutputSize = 0, endOnInputSize = 1 }
endCondition_directive;
-typedef enum { full = 0, partial = 1 } earlyEnd_directive;
+ if (LZ4_64bits()) if ((pIn<(pInLimit-3)) && (LZ4_read32(pMatch) ==
LZ4_read32(pIn))) { pIn+=4; pMatch+=4; }
+ if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) {
pIn+=2; pMatch+=2; }
+ if ((pIn<pInLimit) && (*pMatch == *pIn)) pIn++;
+ return (unsigned)(pIn - pStart);
+}
-//**************************************
-// 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); }
-#define LZ4_SECURECOPY(d,s,e) { if ((STEPSIZE==4)||(d<e))
LZ4_WILDCOPY(d,s,e); }
-
-#if LZ4_ARCH64 // 64-bit
-# define HTYPE U32
-# define INITBASE(base) const BYTE* const base = ip
-#else // 32-bit
-# define HTYPE const BYTE*
-# define INITBASE(base) const int base = 0
-#endif
+#ifndef LZ4_COMMONDEFS_ONLY
+/**************************************
+* Local Constants
+**************************************/
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
+#define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static
allocation */
-#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
+static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT-1));
+static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression
run slower on incompressible data */
-//**************************************
-// Macros
-//**************************************
-#define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); }
// at the end, d>=e;
-
-
-//****************************
-// Private functions
-//****************************
-#if LZ4_ARCH64
-
-FORCE_INLINE 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
-}
+/**************************************
+* Local Structures and types
+**************************************/
+typedef struct {
+ U32 hashTable[HASH_SIZE_U32];
+ U32 currentOffset;
+ U32 initCheck;
+ const BYTE* dictionary;
+ BYTE* bufferStart; /* obsolete, used for slideInputBuffer */
+ U32 dictSize;
+} LZ4_stream_t_internal;
+
+typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { byPtr, byU32, byU16 } tableType_t;
-#else
+typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
-FORCE_INLINE 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
-}
+typedef enum { endOnOutputSize = 0, endOnInputSize = 1 }
endCondition_directive;
+typedef enum { full = 0, partial = 1 } earlyEnd_directive;
-#endif
+/**************************************
+* 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
-//****************************
-FORCE_INLINE int LZ4_hashSequence(U32 sequence, tableType_t tableType)
+
+
+/********************************
+* Compression functions
+********************************/
+
+static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType)
{
if (tableType == byU16)
return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
@@ -379,220 +386,539 @@ FORCE_INLINE int LZ4_hashSequence(U32 sequence,
tableType_t tableType)
return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
}
-FORCE_INLINE int LZ4_hashPosition(const BYTE* p, tableType_t tableType) {
return LZ4_hashSequence(A32(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;
+}
-FORCE_INLINE void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase,
tableType_t tableType, const BYTE* srcBase)
+static U32 LZ4_hashSequenceT(size_t sequence, tableType_t const tableType)
+{
+ if (LZ4_64bits())
+ return LZ4_hashSequence64(sequence, tableType);
+ return LZ4_hashSequence((U32)sequence, tableType);
+}
+
+static U32 LZ4_hashPosition(const void* p, tableType_t tableType) { return
LZ4_hashSequenceT(LZ4_read_ARCH(p), tableType); }
+
+static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase,
tableType_t const tableType, const BYTE* srcBase)
{
switch (tableType)
{
- case byPtr: { const BYTE** hashTable = (const BYTE**) tableBase;
hashTable[h] = p; 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; }
+ case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase;
hashTable[h] = p; return; }
+ case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] =
(U32)(p-srcBase); return; }
+ case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] =
(U16)(p-srcBase); return; }
}
}
-FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t
tableType, const BYTE* srcBase)
+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);
}
-FORCE_INLINE const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase,
tableType_t tableType, const BYTE* 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
+ { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /*
default, to ensure a return */
}
-FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase,
tableType_t tableType, const BYTE* srcBase)
+static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t
tableType, const BYTE* srcBase)
{
U32 h = LZ4_hashPosition(p, tableType);
return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
}
-
FORCE_INLINE int LZ4_compress_generic(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize,
-
- limitedOutput_directive limitedOutput,
- tableType_t tableType,
- prefix64k_directive prefix)
+ void* const ctx,
+ const char* const source,
+ char* const dest,
+ const int inputSize,
+ const int maxOutputSize,
+ const limitedOutput_directive outputLimited,
+ const tableType_t tableType,
+ const dict_directive dict,
+ const dictIssue_directive dictIssue,
+ const U32 acceleration)
{
+ LZ4_stream_t_internal* const dictPtr = (LZ4_stream_t_internal*)ctx;
+
const BYTE* ip = (const BYTE*) source;
- const BYTE* const base = (prefix==withPrefix) ?
((LZ4_Data_Structure*)ctx)->base : (const BYTE*) source;
- const BYTE* const lowLimit = ((prefix==withPrefix) ?
((LZ4_Data_Structure*)ctx)->bufferStart : (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 oend = op + maxOutputSize;
+ BYTE* const olimit = op + maxOutputSize;
- int length;
- 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)
- if ((prefix==withPrefix) && (ip != ((LZ4_Data_Structure*)ctx)->nextBlock))
return 0; // must continue from end of previous block
- if (prefix==withPrefix) ((LZ4_Data_Structure*)ctx)->nextBlock=iend;
// do it now, due to potential early exit
- if ((tableType == byU16) && (inputSize>=LZ4_64KLIMIT)) return 0;
// Size too large (not within 64K limit)
- if (inputSize<LZ4_minLength) goto _last_literals;
// Input too small, no compression (all literals)
+ /* Init conditions */
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported
input size, too large (or negative) */
+ switch(dict)
+ {
+ case noDict:
+ default:
+ base = (const BYTE*)source;
+ lowLimit = (const BYTE*)source;
+ break;
+ case withPrefix64k:
+ base = (const BYTE*)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE*)source - dictPtr->dictSize;
+ break;
+ case usingExtDict:
+ base = (const BYTE*)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE*)source;
+ break;
+ }
+ if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size
too large (not within 64K limit) */
+ if (inputSize<LZ4_minLength) goto _last_literals; /*
Input too small, no compression (all literals) */
- // First Byte
+ /* First Byte */
LZ4_putPosition(ip, ctx, tableType, base);
ip++; forwardH = LZ4_hashPosition(ip, tableType);
- // Main Loop
+ /* Main Loop */
for ( ; ; )
{
- int findMatchAttempts = (1U << skipStrength) + 3;
- const BYTE* forwardIp = ip;
- const BYTE* ref;
+ const BYTE* match;
BYTE* token;
+ {
+ const BYTE* forwardIp = ip;
+ unsigned step = 1;
+ unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
+
+ /* Find a match */
+ do {
+ U32 h = forwardH;
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+ if (unlikely(forwardIp > mflimit)) goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, ctx, tableType, base);
+ if (dict==usingExtDict)
+ {
+ if (match<(const BYTE*)source)
+ {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ }
+ else
+ {
+ refDelta = 0;
+ lowLimit = (const BYTE*)source;
+ }
+ }
+ forwardH = LZ4_hashPosition(forwardIp, tableType);
+ LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
+
+ } while ( ((dictIssue==dictSmall) ? (match < lowRefLimit) : 0)
+ || ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match+refDelta) != LZ4_read32(ip)) );
+ }
- // Find a match
- do {
- U32 h = forwardH;
- int step = findMatchAttempts++ >> skipStrength;
- ip = forwardIp;
- forwardIp = ip + step;
-
- if unlikely(forwardIp > mflimit) { goto _last_literals; }
+ /* Catch up */
+ while ((ip>anchor) && (match+refDelta > lowLimit) &&
(unlikely(ip[-1]==match[refDelta-1]))) { ip--; match--; }
- forwardH = LZ4_hashPosition(forwardIp, tableType);
- ref = LZ4_getPositionOnHash(h, ctx, tableType, base);
- LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
+ {
+ /* 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);
- } while ((ref + MAX_DISTANCE < ip) || (A32(ref) != A32(ip)));
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op+litLength);
+ op+=litLength;
+ }
- // Catch up
- while ((ip>anchor) && (ref > lowLimit) && unlikely(ip[-1]==ref[-1])) {
ip--; ref--; }
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
- // Encode Literal length
- length = (int)(ip - anchor);
- token = op++;
- if ((limitedOutput) && unlikely(op + length + (2 + 1 + LASTLITERALS) +
(length/255) > oend)) return 0; // Check output limit
- if (length>=(int)RUN_MASK)
+ /* Encode MatchLength */
{
- int len = length-RUN_MASK;
- *token=(RUN_MASK<<ML_BITS);
- for(; len >= 255 ; len-=255) *op++ = 255;
- *op++ = (BYTE)len;
- }
- else *token = (BYTE)(length<<ML_BITS);
+ unsigned matchLength;
- // Copy Literals
- { BYTE* end=(op)+(length); LZ4_WILDCOPY(op,anchor,end); op=end; }
+ if ((dict==usingExtDict) && (lowLimit==dictionary))
+ {
+ const BYTE* limit;
+ match += refDelta;
+ limit = ip + (dictEnd-match);
+ if (limit > matchlimit) limit = matchlimit;
+ matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, limit);
+ ip += MINMATCH + matchLength;
+ if (ip==limit)
+ {
+ unsigned more = LZ4_count(ip, (const BYTE*)source,
matchlimit);
+ matchLength += more;
+ ip += more;
+ }
+ }
+ else
+ {
+ matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH,
matchlimit);
+ ip += MINMATCH + matchLength;
+ }
-_next_match:
- // Encode Offset
- LZ4_WRITE_LITTLEENDIAN_16(op,(U16)(ip-ref));
+ if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) +
(matchLength>>8) > olimit)))
+ return 0; /* Check output limit */
+ if (matchLength>=ML_MASK)
+ {
+ *token += ML_MASK;
+ matchLength -= ML_MASK;
+ for (; matchLength >= 510 ; matchLength-=510) { *op++ = 255;
*op++ = 255; }
+ if (matchLength >= 255) { matchLength-=255; *op++ = 255; }
+ *op++ = (BYTE)matchLength;
+ }
+ else *token += (BYTE)(matchLength);
+ }
- // Start Counting
- ip+=MINMATCH; ref+=MINMATCH; // MinMatch already verified
anchor = ip;
- while likely(ip<matchlimit-(STEPSIZE-1))
- {
- size_t diff = AARCH(ref) ^ AARCH(ip);
- if (!diff) { ip+=STEPSIZE; ref+=STEPSIZE; continue; }
- ip += LZ4_NbCommonBytes(diff);
- goto _endCount;
- }
- if (LZ4_ARCH64) if ((ip<(matchlimit-3)) && (A32(ref) == A32(ip))) {
ip+=4; ref+=4; }
- if ((ip<(matchlimit-1)) && (A16(ref) == A16(ip))) { ip+=2; ref+=2; }
- if ((ip<matchlimit) && (*ref == *ip)) ip++;
-_endCount:
-
- // Encode MatchLength
- length = (int)(ip - anchor);
- if ((limitedOutput) && unlikely(op + (1 + LASTLITERALS) + (length>>8)
> oend)) return 0; // Check output limit
- if (length>=(int)ML_MASK)
- {
- *token += ML_MASK;
- length -= ML_MASK;
- for (; length > 509 ; length-=510) { *op++ = 255; *op++ = 255; }
- if (length >= 255) { length-=255; *op++ = 255; }
- *op++ = (BYTE)length;
- }
- else *token += (BYTE)(length);
- // Test end of chunk
- if (ip > mflimit) { anchor = ip; break; }
+ /* Test end of chunk */
+ if (ip > mflimit) break;
- // Fill table
+ /* Fill table */
LZ4_putPosition(ip-2, ctx, tableType, base);
- // Test next position
- ref = LZ4_getPosition(ip, ctx, tableType, base);
+ /* Test next position */
+ match = LZ4_getPosition(ip, ctx, tableType, base);
+ if (dict==usingExtDict)
+ {
+ if (match<(const BYTE*)source)
+ {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ }
+ else
+ {
+ refDelta = 0;
+ lowLimit = (const BYTE*)source;
+ }
+ }
LZ4_putPosition(ip, ctx, tableType, base);
- if ((ref + MAX_DISTANCE >= ip) && (A32(ref) == A32(ip))) { token =
op++; *token=0; goto _next_match; }
+ if ( ((dictIssue==dictSmall) ? (match>=lowRefLimit) : 1)
+ && (match+MAX_DISTANCE>=ip)
+ && (LZ4_read32(match+refDelta)==LZ4_read32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
- // Prepare next loop
- anchor = ip++;
- forwardH = LZ4_hashPosition(ip, tableType);
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
}
_last_literals:
- // Encode Last Literals
+ /* Encode Last Literals */
{
- int lastRun = (int)(iend - anchor);
- if ((limitedOutput) && (((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;
+ const size_t lastRun = (size_t)(iend - anchor);
+ if ((outputLimited) && ((op - (BYTE*)dest) + lastRun + 1 +
((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize))
+ return 0; /* Check output limit */
+ if (lastRun >= RUN_MASK)
+ {
+ size_t accumulator = lastRun - RUN_MASK;
+ *op++ = RUN_MASK << ML_BITS;
+ for(; accumulator >= 255 ; accumulator-=255) *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ }
+ else
+ {
+ *op++ = (BYTE)(lastRun<<ML_BITS);
+ }
+ memcpy(op, anchor, lastRun);
+ op += lastRun;
}
- // End
+ /* End */
return (int) (((char*)op)-dest);
}
-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(HASHNBCELLS4, 4); // Aligned on 4-bytes boundaries
+ void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc
always properly aligned */
#else
- U32 ctx[1U<<(MEMORY_USAGE-2)] = {0}; // Ensure data is aligned
on 4-bytes boundaries
+ LZ4_stream_t ctx;
+ void* ctxPtr = &ctx;
#endif
- int result;
- if (inputSize < (int)LZ4_64KLIMIT)
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0,
notLimited, byU16, noPrefix);
- else
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0,
notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noPrefix);
+ int result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize,
maxOutputSize, acceleration);
#if (HEAPMODE)
- FREEMEM(ctx);
+ FREEMEM(ctxPtr);
#endif
return result;
}
-int LZ4_compress_continue (void* LZ4_Data, const char* source, char* dest, int
inputSize)
+
+int LZ4_compress_default(const char* source, char* dest, int inputSize, int
maxOutputSize)
{
- return LZ4_compress_generic(LZ4_Data, source, dest, inputSize, 0,
notLimited, byU32, withPrefix);
+ return LZ4_compress_fast(source, dest, inputSize, maxOutputSize, 1);
}
-int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize,
int maxOutputSize)
+/* hidden debug function */
+/* strangely enough, gcc generates faster code when this function is
uncommented, even if unused */
+int LZ4_compress_fast_force(const char* source, char* dest, int inputSize, int
maxOutputSize, int acceleration)
+{
+ LZ4_stream_t ctx;
+
+ LZ4_resetStream(&ctx);
+
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(&ctx, source, dest, inputSize,
maxOutputSize, limitedOutput, byU16, noDict,
noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(&ctx, source, dest, inputSize,
maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict,
noDictIssue, acceleration);
+}
+
+
+/********************************
+* destSize variant
+********************************/
+
+static int LZ4_compress_destSize_generic(
+ void* const ctx,
+ const char* const src,
+ char* const dst,
+ int* const srcSizePtr,
+ const int targetDstSize,
+ const tableType_t tableType)
+{
+ const BYTE* ip = (const BYTE*) src;
+ const BYTE* base = (const BYTE*) src;
+ const BYTE* lowLimit = (const BYTE*) src;
+ const BYTE* anchor = ip;
+ const BYTE* const iend = ip + *srcSizePtr;
+ const BYTE* const mflimit = iend - MFLIMIT;
+ const BYTE* const matchlimit = iend - LASTLITERALS;
+
+ BYTE* op = (BYTE*) dst;
+ BYTE* const oend = op + targetDstSize;
+ BYTE* const oMaxLit = op + targetDstSize - 2 /* offset */ - 8 /* because
8+MINMATCH==MFLIMIT */ - 1 /* token */;
+ BYTE* const oMaxMatch = op + targetDstSize - (LASTLITERALS + 1 /* token
*/);
+ BYTE* const oMaxSeq = oMaxLit - 1 /* token */;
+
+ U32 forwardH;
+
+
+ /* Init conditions */
+ if (targetDstSize < 1) return 0; /*
Impossible to store anything */
+ if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /*
Unsupported input size, too large (or negative) */
+ if ((tableType == byU16) && (*srcSizePtr>=LZ4_64Klimit)) return 0; /*
Size too large (not within 64K limit) */
+ if (*srcSizePtr<LZ4_minLength) goto _last_literals; /*
Input too small, no compression (all literals) */
+
+ /* First Byte */
+ *srcSizePtr = 0;
+ LZ4_putPosition(ip, ctx, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; )
+ {
+ const BYTE* match;
+ BYTE* token;
+ {
+ const BYTE* forwardIp = ip;
+ unsigned step = 1;
+ unsigned searchMatchNb = 1 << LZ4_skipTrigger;
+
+ /* Find a match */
+ do {
+ U32 h = forwardH;
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+ if (unlikely(forwardIp > mflimit))
+ goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, ctx, tableType, base);
+ forwardH = LZ4_hashPosition(forwardIp, tableType);
+ LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
+
+ } while ( ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match) != LZ4_read32(ip)) );
+ }
+
+ /* Catch up */
+ while ((ip>anchor) && (match > lowLimit) &&
(unlikely(ip[-1]==match[-1]))) { ip--; match--; }
+
+ {
+ /* Encode Literal length */
+ unsigned litLength = (unsigned)(ip - anchor);
+ token = op++;
+ if (op + ((litLength+240)/255) + litLength > oMaxLit)
+ {
+ /* Not enough space for a last match */
+ op--;
+ goto _last_literals;
+ }
+ if (litLength>=RUN_MASK)
+ {
+ unsigned len = litLength - RUN_MASK;
+ *token=(RUN_MASK<<ML_BITS);
+ for(; len >= 255 ; len-=255) *op++ = 255;
+ *op++ = (BYTE)len;
+ }
+ else *token = (BYTE)(litLength<<ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op+litLength);
+ op += litLength;
+ }
+
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
+
+ /* Encode MatchLength */
+ {
+ size_t matchLength;
+
+ matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
+
+ if (op + ((matchLength+240)/255) > oMaxMatch)
+ {
+ /* Match description too long : reduce it */
+ matchLength = (15-1) + (oMaxMatch-op) * 255;
+ }
+ //printf("offset %5i, matchLength%5i \n", (int)(ip-match),
matchLength + MINMATCH);
+ ip += MINMATCH + matchLength;
+
+ if (matchLength>=ML_MASK)
+ {
+ *token += ML_MASK;
+ matchLength -= ML_MASK;
+ while (matchLength >= 255) { matchLength-=255; *op++ = 255; }
+ *op++ = (BYTE)matchLength;
+ }
+ else *token += (BYTE)(matchLength);
+ }
+
+ anchor = ip;
+
+ /* Test end of block */
+ if (ip > mflimit) break;
+ if (op > oMaxSeq) break;
+
+ /* Fill table */
+ LZ4_putPosition(ip-2, ctx, tableType, base);
+
+ /* Test next position */
+ match = LZ4_getPosition(ip, ctx, tableType, base);
+ LZ4_putPosition(ip, ctx, tableType, base);
+ if ( (match+MAX_DISTANCE>=ip)
+ && (LZ4_read32(match)==LZ4_read32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
+
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
+ }
+
+_last_literals:
+ /* Encode Last Literals */
+ {
+ size_t lastRunSize = (size_t)(iend - anchor);
+ if (op + 1 /* token */ + ((lastRunSize+240)/255) /* litLength */ +
lastRunSize /* literals */ > oend)
+ {
+ /* adapt lastRunSize to fill 'dst' */
+ lastRunSize = (oend-op) - 1;
+ lastRunSize -= (lastRunSize+240)/255;
+ }
+ ip = anchor + lastRunSize;
+
+ if (lastRunSize >= RUN_MASK)
+ {
+ size_t accumulator = lastRunSize - RUN_MASK;
+ *op++ = RUN_MASK << ML_BITS;
+ for(; accumulator >= 255 ; accumulator-=255) *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ }
+ else
+ {
+ *op++ = (BYTE)(lastRunSize<<ML_BITS);
+ }
+ memcpy(op, anchor, lastRunSize);
+ op += lastRunSize;
+ }
+
+ /* End */
+ *srcSizePtr = (int) (((const char*)ip)-src);
+ return (int) (((char*)op)-dst);
+}
+
+
+static int LZ4_compress_destSize_extState (void* state, const char* src, char*
dst, int* srcSizePtr, int targetDstSize)
+{
+ LZ4_resetStream((LZ4_stream_t*)state);
+
+ if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) /* compression
success is guaranteed */
+ {
+ return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr,
targetDstSize, 1);
+ }
+ else
+ {
+ if (*srcSizePtr < LZ4_64Klimit)
+ return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr,
targetDstSize, byU16);
+ else
+ return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr,
targetDstSize, LZ4_64bits() ? byU32 : byPtr);
+ }
+}
+
+
+int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int
targetDstSize)
{
#if (HEAPMODE)
- void* ctx = ALLOCATOR(HASHNBCELLS4, 4); // Aligned on 4-bytes boundaries
+ void* ctx = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always
properly aligned */
#else
- U32 ctx[1U<<(MEMORY_USAGE-2)] = {0}; // Ensure data is aligned
on 4-bytes boundaries
+ LZ4_stream_t ctxBody;
+ void* ctx = &ctxBody;
#endif
- int result;
- if (inputSize < (int)LZ4_64KLIMIT)
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize,
maxOutputSize, limited, byU16, noPrefix);
- else
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize,
maxOutputSize, limited, (sizeof(void*)==8) ? byU32 : byPtr, noPrefix);
+ int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr,
targetDstSize);
#if (HEAPMODE)
FREEMEM(ctx);
@@ -600,231 +926,591 @@ int LZ4_compress_limitedOutput(const char* source,
char* dest, int inputSize, in
return result;
}
-int LZ4_compress_limitedOutput_continue (void* LZ4_Data, const char* source,
char* dest, int inputSize, int maxOutputSize)
+
+
+/********************************
+* Streaming functions
+********************************/
+
+LZ4_stream_t* LZ4_createStream(void)
{
- return LZ4_compress_generic(LZ4_Data, source, dest, inputSize,
maxOutputSize, limited, byU32, withPrefix);
+ LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(8, LZ4_STREAMSIZE_U64);
+ LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /*
A compilation error here means LZ4_STREAMSIZE is not large enough */
+ LZ4_resetStream(lz4s);
+ return lz4s;
}
+void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
+{
+ MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
-//****************************
-// Stream functions
-//****************************
-
-FORCE_INLINE void LZ4_init(LZ4_Data_Structure* lz4ds, const BYTE* base)
+int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
{
- MEM_INIT(lz4ds->hashTable, 0, sizeof(lz4ds->hashTable));
- lz4ds->bufferStart = base;
- lz4ds->base = base;
- lz4ds->nextBlock = base;
+ FREEMEM(LZ4_stream);
+ return (0);
}
-void* LZ4_create (const char* inputBuffer)
+#define HASH_UNIT sizeof(size_t)
+int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
{
- void* lz4ds = ALLOCATOR(1, sizeof(LZ4_Data_Structure));
- LZ4_init ((LZ4_Data_Structure*)lz4ds, (const BYTE*)inputBuffer);
- return lz4ds;
+ LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
+ const BYTE* p = (const BYTE*)dictionary;
+ const BYTE* const dictEnd = p + dictSize;
+ const BYTE* base;
+
+ if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized
structure, or reuse overflow */
+ LZ4_resetStream(LZ4_dict);
+
+ if (dictSize < (int)HASH_UNIT)
+ {
+ dict->dictionary = NULL;
+ dict->dictSize = 0;
+ return 0;
+ }
+
+ if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB;
+ dict->currentOffset += 64 KB;
+ base = p - dict->currentOffset;
+ dict->dictionary = p;
+ dict->dictSize = (U32)(dictEnd - p);
+ dict->currentOffset += dict->dictSize;
+
+ while (p <= dictEnd-HASH_UNIT)
+ {
+ LZ4_putPosition(p, dict->hashTable, byU32, base);
+ p+=3;
+ }
+
+ return dict->dictSize;
}
-int LZ4_free (void* LZ4_Data)
+static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
{
- FREEMEM(LZ4_Data);
- return (0);
+ 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;
+ }
}
-char* LZ4_slideInputBuffer (void* LZ4_Data)
+int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source,
char* dest, int inputSize, int maxOutputSize, int acceleration)
{
- LZ4_Data_Structure* lz4ds = (LZ4_Data_Structure*)LZ4_Data;
- size_t delta = lz4ds->nextBlock - (lz4ds->bufferStart + 64 KB);
+ LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_stream;
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- if ( (lz4ds->base - delta > lz4ds->base) //
underflow control
- || ((size_t)(lz4ds->nextBlock - lz4ds->base) > 0xE0000000) ) // close
to 32-bits limit
- {
- size_t deltaLimit = (lz4ds->nextBlock - 64 KB) - lz4ds->base;
- int nH;
+ const BYTE* smallest = (const BYTE*) source;
+ if (streamPtr->initCheck) return 0; /* Uninitialized structure detected
*/
+ if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd;
+ LZ4_renormDictT(streamPtr, smallest);
+ if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
- for (nH=0; nH < HASHNBCELLS4; nH++)
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE* sourceEnd = (const BYTE*) source + inputSize;
+ if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd))
{
- if ((size_t)(lz4ds->hashTable[nH]) < deltaLimit)
lz4ds->hashTable[nH] = 0;
- else lz4ds->hashTable[nH] -= (U32)deltaLimit;
+ 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;
}
- memcpy((void*)(lz4ds->bufferStart), (const void*)(lz4ds->nextBlock -
64 KB), 64 KB);
- lz4ds->base = lz4ds->bufferStart;
- lz4ds->nextBlock = lz4ds->base + 64 KB;
}
- else
+
+ /* prefix mode : source data follows dictionary */
+ if (dictEnd == (const BYTE*)source)
+ {
+ int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize <
streamPtr->currentOffset))
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize,
maxOutputSize, limitedOutput, byU32, withPrefix64k, dictSmall, acceleration);
+ else
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize,
maxOutputSize, limitedOutput, byU32, withPrefix64k, noDictIssue, acceleration);
+ streamPtr->dictSize += (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+
+ /* external dictionary mode */
{
- memcpy((void*)(lz4ds->bufferStart), (const void*)(lz4ds->nextBlock -
64 KB), 64 KB);
- lz4ds->nextBlock -= delta;
- lz4ds->base -= delta;
+ int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize <
streamPtr->currentOffset))
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize,
maxOutputSize, limitedOutput, byU32, usingExtDict, dictSmall, acceleration);
+ else
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize,
maxOutputSize, limitedOutput, byU32, usingExtDict, noDictIssue, acceleration);
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
}
+}
+
+
+/* Hidden debug function, to force external dictionary mode */
+int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source,
char* dest, int inputSize)
+{
+ LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_dict;
+ int result;
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
- return (char*)(lz4ds->nextBlock);
+ const BYTE* smallest = dictEnd;
+ if (smallest > (const BYTE*) source) smallest = (const BYTE*) source;
+ LZ4_renormDictT((LZ4_stream_t_internal*)LZ4_dict, smallest);
+
+ result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0,
notLimited, byU32, usingExtDict, noDictIssue, 1);
+
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+
+ return result;
}
-//****************************
-// Decompression functions
-//****************************
+int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize)
+{
+ LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
+ const BYTE* previousDictEnd = dict->dictionary + dict->dictSize;
+
+ if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a
dictionary > 64 KB */
+ if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize;
-// 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.
+ memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+ dict->dictionary = (const BYTE*)safeBuffer;
+ dict->dictSize = (U32)dictSize;
+
+ return dictSize;
+}
+
+
+
+/*******************************
+* Decompression functions
+*******************************/
+/*
+ * This generic decompression function cover all use cases.
+ * It shall be instantiated several times, using different sets of directives
+ * Note that it is essential this generic function is really inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
FORCE_INLINE int LZ4_decompress_generic(
- const char* source,
- char* dest,
- int inputSize, //
- int outputSize, // If endOnInput==endOnInputSize,
this value is the max size of Output Buffer.
-
- int endOnInput, // endOnOutputSize, endOnInputSize
- int prefix64k, // noPrefix, withPrefix
- int partialDecoding, // full, partial
- int targetOutputSize // only used if
partialDecoding==partial
+ const char* const source,
+ char* const dest,
+ int inputSize,
+ int outputSize, /* If endOnInput==endOnInputSize,
this value is the max size of Output Buffer. */
+
+ int endOnInput, /* endOnOutputSize, endOnInputSize */
+ int partialDecoding, /* full, partial */
+ int targetOutputSize, /* only used if
partialDecoding==partial */
+ int dict, /* noDict, withPrefix64k,
usingExtDict */
+ const BYTE* const lowPrefix, /* == dest if dict == noDict */
+ const BYTE* const dictStart, /* only if dict==usingExtDict */
+ const size_t dictSize /* note : = 0 if noDict */
)
{
- // Local Variables
- const BYTE* restrict ip = (const BYTE*) source;
- const BYTE* ref;
+ /* Local Variables */
+ const BYTE* ip = (const BYTE*) source;
const BYTE* const iend = ip + inputSize;
BYTE* op = (BYTE*) dest;
BYTE* const oend = op + outputSize;
BYTE* cpy;
BYTE* oexit = op + targetOutputSize;
+ const BYTE* const lowLimit = lowPrefix - dictSize;
- const size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; // static reduces
speed for LZ4_decompress_safe() on GCC64
- static const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
+ const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize;
+ const size_t dec32table[] = {4, 1, 2, 1, 4, 4, 4, 4};
+ const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
+ const int safeDecode = (endOnInput==endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
- // Special cases
- if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT;
// targetOutputSize too high => decode everything
- if ((endOnInput) && unlikely(outputSize==0)) return ((inputSize==1) &&
(*ip==0)) ? 0 : -1; // Empty output buffer
- if ((!endOnInput) && unlikely(outputSize==0)) return (*ip==0?1:-1);
+ /* 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
+
+ /* Main Loop */
while (1)
{
unsigned token;
size_t length;
+ const BYTE* match;
- // get runlength
+ /* get literal length */
token = *ip++;
if ((length=(token>>ML_BITS)) == RUN_MASK)
{
- unsigned s=255;
- while (((endOnInput)?ip<iend:1) && (s==255))
+ unsigned s;
+ do
{
s = *ip++;
length += s;
}
+ while (likely((endOnInput)?ip<iend-RUN_MASK:1) && (s==255));
+ if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)(op)))
goto _output_error; /* overflow detection */
+ if ((safeDecode) && unlikely((size_t)(ip+length)<(size_t)(ip)))
goto _output_error; /* overflow detection */
}
- // copy literals
+ /* 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
+ 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
+ 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
+ break; /* Necessarily EOF, due to parsing restrictions */
}
- LZ4_WILDCOPY(op, ip, cpy); ip -= (op-cpy); op = cpy;
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length; op = cpy;
- // get offset
- LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;
- if ((prefix64k==noPrefix) && unlikely(ref < (BYTE* const)dest)) goto
_output_error; // Error : offset outside destination buffer
+ /* get offset */
+ match = cpy - LZ4_readLE16(ip); ip+=2;
+ if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error;
/* Error : offset outside destination buffer */
- // get matchlength
- if ((length=(token&ML_MASK)) == ML_MASK)
+ /* get matchlength */
+ length = token & ML_MASK;
+ if (length == ML_MASK)
{
- while ((!endOnInput) || (ip<iend-(LASTLITERALS+1))) // Ensure
enough bytes remain for LASTLITERALS + token
+ unsigned s;
+ do
{
- unsigned s = *ip++;
+ if ((endOnInput) && (ip > iend-LASTLITERALS)) goto
_output_error;
+ s = *ip++;
length += s;
- if (s==255) continue;
- break;
+ } while (s==255);
+ if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)op)) goto
_output_error; /* overflow detection */
+ }
+ length += MINMATCH;
+
+ /* check external dictionary */
+ if ((dict==usingExtDict) && (match < lowPrefix))
+ {
+ if (unlikely(op+length > oend-LASTLITERALS)) goto _output_error;
/* doesn't respect parsing restriction */
+
+ if (length <= (size_t)(lowPrefix-match))
+ {
+ /* match can be copied as a single segment from external
dictionary */
+ match = dictEnd - (lowPrefix-match);
+ memmove(op, match, length); op += length;
+ }
+ else
+ {
+ /* match encompass external dictionary and current segment */
+ size_t copySize = (size_t)(lowPrefix-match);
+ memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+ copySize = length - copySize;
+ if (copySize > (size_t)(op-lowPrefix)) /* overlap within
current segment */
+ {
+ BYTE* const endOfMatch = op + copySize;
+ const BYTE* copyFrom = lowPrefix;
+ while (op < endOfMatch) *op++ = *copyFrom++;
+ }
+ else
+ {
+ memcpy(op, lowPrefix, copySize);
+ op += copySize;
+ }
}
+ continue;
}
- // copy repeated sequence
- if unlikely((op-ref)<(int)STEPSIZE)
+ /* copy repeated sequence */
+ cpy = op + length;
+ if (unlikely((op-match)<8))
{
- 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];
- op += 4, ref += 4; ref -= dec32table[op-ref];
- A32(op) = A32(ref);
- op += STEPSIZE-4; ref -= dec64;
- } else { LZ4_COPYSTEP(op,ref); }
- cpy = op + length - (STEPSIZE-4);
-
- if unlikely(cpy>oend-COPYLENGTH-(STEPSIZE-4))
+ const size_t dec64 = dec64table[op-match];
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += dec32table[op-match];
+ LZ4_copy4(op+4, match);
+ op += 8; match -= dec64;
+ } else { LZ4_copy8(op, match); op+=8; match+=8; }
+
+ if (unlikely(cpy>oend-12))
{
- if (cpy > oend-LASTLITERALS) goto _output_error; // Error :
last 5 bytes must be literals
- LZ4_SECURECOPY(op, ref, (oend-COPYLENGTH));
- while(op<cpy) *op++=*ref++;
- op=cpy;
- continue;
+ if (cpy > oend-LASTLITERALS) goto _output_error; /* Error :
last LASTLITERALS bytes must be literals */
+ if (op < oend-8)
+ {
+ LZ4_wildCopy(op, match, oend-8);
+ match += (oend-8) - op;
+ op = oend-8;
+ }
+ while (op<cpy) *op++ = *match++;
}
- LZ4_WILDCOPY(op, ref, cpy);
- op=cpy; // correction
+ else
+ LZ4_wildCopy(op, match, cpy);
+ op=cpy; /* correction */
}
- // end of decoding
+ /* end of decoding */
if (endOnInput)
- return (int) (((char*)op)-dest); // Nb of output bytes decoded
+ 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
+ /* Overflow error detected */
_output_error:
- return (int) (-(((char*)ip)-source))-1;
+ return (int) (-(((const char*)ip)-source))-1;
}
-int LZ4_decompress_safe(const char* source, char* dest, int inputSize, int
maxOutputSize)
+int LZ4_decompress_safe(const char* source, char* dest, int compressedSize,
int maxDecompressedSize)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize,
endOnInputSize, noPrefix, full, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize,
maxDecompressedSize, endOnInputSize, full, 0, noDict, (BYTE*)dest, NULL, 0);
}
-int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int
inputSize, int maxOutputSize)
+int LZ4_decompress_safe_partial(const char* source, char* dest, int
compressedSize, int targetOutputSize, int maxDecompressedSize)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize,
endOnInputSize, withPrefix, full, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize,
maxDecompressedSize, endOnInputSize, partial, targetOutputSize, noDict,
(BYTE*)dest, NULL, 0);
}
-int LZ4_decompress_safe_partial(const char* source, char* dest, int inputSize,
int targetOutputSize, int maxOutputSize)
+int LZ4_decompress_fast(const char* source, char* dest, int originalSize)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize,
endOnInputSize, noPrefix, partial, targetOutputSize);
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
endOnOutputSize, full, 0, withPrefix64k, (BYTE*)(dest - 64 KB), NULL, 64 KB);
}
-int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int
outputSize)
+
+/* streaming decompression functions */
+
+typedef struct
{
- return LZ4_decompress_generic(source, dest, 0, outputSize,
endOnOutputSize, withPrefix, full, 0);
+ const BYTE* externalDict;
+ size_t extDictSize;
+ const BYTE* prefixEnd;
+ size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+
+/*
+ * If you prefer dynamic allocation methods,
+ * LZ4_createStreamDecode()
+ * provides a pointer (void*) towards an initialized LZ4_streamDecode_t
structure.
+ */
+LZ4_streamDecode_t* LZ4_createStreamDecode(void)
+{
+ LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(1,
sizeof(LZ4_streamDecode_t));
+ return lz4s;
}
-int LZ4_decompress_fast(const char* source, char* dest, int outputSize)
+int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream)
{
-#ifdef _MSC_VER // This version is faster with Visual
- return LZ4_decompress_generic(source, dest, 0, outputSize,
endOnOutputSize, noPrefix, full, 0);
-#else
- return LZ4_decompress_generic(source, dest, 0, outputSize,
endOnOutputSize, withPrefix, full, 0);
-#endif
+ FREEMEM(LZ4_stream);
+ return 0;
}
-#endif
+
+/*
+ * LZ4_setStreamDecode
+ * Use this function to instruct where to find the dictionary
+ * This function is not necessary if previous data is still available where it
was decoded.
+ * Loading a size of 0 is allowed (same effect as no dictionary).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char*
dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*)
LZ4_streamDecode;
+ lz4sd->prefixSize = (size_t) dictSize;
+ lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize;
+ lz4sd->externalDict = NULL;
+ lz4sd->extDictSize = 0;
+ return 1;
+}
+
+/*
+*_continue() :
+ These decoding functions allow decompression of multiple blocks in
"streaming" mode.
+ Previously decoded blocks must still be available at the memory position
where they were decoded.
+ If it's not possible, save the relevant part of decoded data into a safe
buffer,
+ and indicate where it stands using LZ4_setStreamDecode()
+*/
+int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const
char* source, char* dest, int compressedSize, int maxOutputSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*)
LZ4_streamDecode;
+ int result;
+
+ if (lz4sd->prefixEnd == (BYTE*)dest)
+ {
+ result = LZ4_decompress_generic(source, dest, compressedSize,
maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, lz4sd->prefixEnd -
lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0) return result;
+ lz4sd->prefixSize += result;
+ lz4sd->prefixEnd += result;
+ }
+ else
+ {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_generic(source, dest, compressedSize,
maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, (BYTE*)dest,
lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0) return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE*)dest + result;
+ }
+
+ return result;
+}
+
+int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const
char* source, char* dest, int originalSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*)
LZ4_streamDecode;
+ int result;
+
+ if (lz4sd->prefixEnd == (BYTE*)dest)
+ {
+ result = LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict, lz4sd->prefixEnd -
lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0) return result;
+ lz4sd->prefixSize += originalSize;
+ lz4sd->prefixEnd += originalSize;
+ }
+ else
+ {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = (BYTE*)dest - lz4sd->extDictSize;
+ result = LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict, (BYTE*)dest,
lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0) return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE*)dest + originalSize;
+ }
+
+ return result;
+}
+
+
+/*
+Advanced decoding functions :
+*_usingDict() :
+ These decoding functions work the same as "_continue" ones,
+ the dictionary must be explicitly provided within parameters
+*/
+
+FORCE_INLINE int LZ4_decompress_usingDict_generic(const char* source, char*
dest, int compressedSize, int maxOutputSize, int safe, const char* dictStart,
int dictSize)
+{
+ if (dictSize==0)
+ return LZ4_decompress_generic(source, dest, compressedSize,
maxOutputSize, safe, full, 0, noDict, (BYTE*)dest, NULL, 0);
+ if (dictStart+dictSize == dest)
+ {
+ if (dictSize >= (int)(64 KB - 1))
+ return LZ4_decompress_generic(source, dest, compressedSize,
maxOutputSize, safe, full, 0, withPrefix64k, (BYTE*)dest-64 KB, NULL, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize,
maxOutputSize, safe, full, 0, noDict, (BYTE*)dest-dictSize, NULL, 0);
+ }
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
safe, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
+}
+
+int LZ4_decompress_safe_usingDict(const char* source, char* dest, int
compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
+{
+ return LZ4_decompress_usingDict_generic(source, dest, compressedSize,
maxOutputSize, 1, dictStart, dictSize);
+}
+
+int LZ4_decompress_fast_usingDict(const char* source, char* dest, int
originalSize, const char* dictStart, int dictSize)
+{
+ return LZ4_decompress_usingDict_generic(source, dest, 0, originalSize, 0,
dictStart, dictSize);
+}
+
+/* debug function */
+int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, int
compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
endOnInputSize, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart,
dictSize);
+}
+
+
+/***************************************************
+* Obsolete Functions
+***************************************************/
+/* obsolete compression functions */
+int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize,
int maxOutputSize) { return LZ4_compress_default(source, dest, inputSize,
maxOutputSize); }
+int LZ4_compress(const char* source, char* dest, int inputSize) { return
LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize)); }
+int LZ4_compress_limitedOutput_withState (void* state, const char* src, char*
dst, int srcSize, int dstSize) { return LZ4_compress_fast_extState(state, src,
dst, srcSize, dstSize, 1); }
+int LZ4_compress_withState (void* state, const char* src, char* dst, int
srcSize) { return LZ4_compress_fast_extState(state, src, dst, srcSize,
LZ4_compressBound(srcSize), 1); }
+int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char*
src, char* dst, int srcSize, int maxDstSize) { return
LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, maxDstSize, 1); }
+int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char*
dest, int inputSize) { return LZ4_compress_fast_continue(LZ4_stream, source,
dest, inputSize, LZ4_compressBound(inputSize), 1); }
+
+/*
+These function names are deprecated and should no longer be used.
+They are only provided here for compatibility with older user programs.
+- LZ4_uncompress is totally equivalent to LZ4_decompress_fast
+- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
+*/
+int LZ4_uncompress (const char* source, char* dest, int outputSize) { return
LZ4_decompress_fast(source, dest, outputSize); }
+int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int
isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize,
maxOutputSize); }
+
+
+/* Obsolete Streaming functions */
+
+int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; }
+
+static void LZ4_init(LZ4_stream_t_internal* lz4ds, BYTE* base)
+{
+ MEM_INIT(lz4ds, 0, LZ4_STREAMSIZE);
+ lz4ds->bufferStart = base;
+}
+
+int LZ4_resetStreamState(void* state, char* inputBuffer)
+{
+ if ((((size_t)state) & 3) != 0) return 1; /* Error : pointer is not
aligned on 4-bytes boundary */
+ LZ4_init((LZ4_stream_t_internal*)state, (BYTE*)inputBuffer);
+ return 0;
+}
+
+void* LZ4_create (char* inputBuffer)
+{
+ void* lz4ds = ALLOCATOR(8, LZ4_STREAMSIZE_U64);
+ LZ4_init ((LZ4_stream_t_internal*)lz4ds, (BYTE*)inputBuffer);
+ return lz4ds;
+}
+
+char* LZ4_slideInputBuffer (void* LZ4_Data)
+{
+ LZ4_stream_t_internal* ctx = (LZ4_stream_t_internal*)LZ4_Data;
+ int dictSize = LZ4_saveDict((LZ4_stream_t*)LZ4_Data,
(char*)ctx->bufferStart, 64 KB);
+ return (char*)(ctx->bufferStart + dictSize);
+}
+
+/* Obsolete streaming decompression functions */
+
+int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int
compressedSize, int maxOutputSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
endOnInputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB);
+}
+
+int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int
originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
endOnOutputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB);
+}
+
+#endif /* LZ4_COMMONDEFS_ONLY */
+
diff --git a/src/compat/compat-lz4.h b/src/compat/compat-lz4.h
index a289fcf..3e74002 100644
--- a/src/compat/compat-lz4.h
+++ b/src/compat/compat-lz4.h
@@ -1,7 +1,8 @@
/*
LZ4 - Fast LZ compression algorithm
Header File
- Copyright (C) 2011-2013, Yann Collet.
+ Copyright (C) 2011-2015, Yann Collet.
+
BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
Redistribution and use in source and binary forms, with or without
@@ -28,8 +29,8 @@
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
You can contact the author at :
- - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
- - LZ4 source repository : http://code.google.com/p/lz4/
+ - LZ4 source repository : https://github.com/Cyan4973/lz4
+ - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
*/
#pragma once
@@ -37,167 +38,321 @@
extern "C" {
#endif
+/*
+ * 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),
+ * and can let the library handle its own memory, please use lz4frame.h
instead.
+*/
-//**************************************
-// Compiler Options
-//**************************************
-#if defined(_MSC_VER) && !defined(__cplusplus) // Visual Studio
-# define inline __inline // Visual C is not C99, but supports some
kind of inline
-#endif
+/**************************************
+* Version
+**************************************/
+#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
+#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);
+
+/**************************************
+* Tuning parameter
+**************************************/
+/*
+ * LZ4_MEMORY_USAGE :
+ * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16
-> 64KB; 20 -> 1MB; etc.)
+ * Increasing memory usage improves compression ratio
+ * Reduced memory usage can improve speed, due to cache effect
+ * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
+ */
+#define LZ4_MEMORY_USAGE 14
-//****************************
-// Simple Functions
-//****************************
+/**************************************
+* Simple Functions
+**************************************/
-int LZ4_compress (const char* source, char* dest, int inputSize);
-int LZ4_decompress_safe (const char* source, char* dest, int inputSize, int
maxOutputSize);
+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 'inputSize' 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_VALUE
- 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() :
- maxOutputSize : is the size of the destination buffer (which must be
already allocated)
- return : the number of bytes decoded in the destination buffer
(necessarily <= maxOutputSize)
+ 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
(never writes outside of output buffer, and never reads outside of input
buffer). Therefore, it is 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.
*/
-//****************************
-// 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)
-static inline int LZ4_compressBound(int isize) { return
LZ4_COMPRESSBOUND(isize); }
+/**************************************
+* Advanced Functions
+**************************************/
+#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
+#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) >
(unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
/*
LZ4_compressBound() :
- Provides the maximum size that LZ4 may output in a "worst case" scenario
(input data not compressible)
- primarily useful for memory allocation of output buffer.
- inline function is recommended for the general case,
- macro is also provided when result needs to be evaluated at compilation
(such as stack memory allocation).
-
- 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)
+ 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
(destination buffer size).
+ Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation
(stack memory allocation for example).
+ 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 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);
-int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize,
int maxOutputSize);
/*
-LZ4_compress_limitedOutput() :
- Compress 'inputSize' 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 function never writes outside of provided output buffer.
-
- inputSize : 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 the compression fails
+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 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_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);
-int LZ4_decompress_fast (const char* source, char* dest, int outputSize);
/*
LZ4_decompress_fast() :
- outputSize : is the original (uncompressed) size
+ originalSize : is the original and therefore uncompressed size
return : the number of bytes read from the source buffer (in other words,
the compressed size)
- If the source stream is malformed, the function will stop
decoding and return a negative result.
- note : This function is a bit faster than LZ4_decompress_safe()
- This function never writes outside of output buffers, but may read
beyond input buffer in case of malicious data packet.
- Use this function preferably into a trusted environment (data to
decode comes from a trusted source).
- Destination buffer must be already allocated. Its size must be a
minimum of 'outputSize' bytes.
+ If the source stream is detected malformed, the function will
stop decoding and return a negative result.
+ Destination buffer must be already allocated. Its size must be a
minimum of 'originalSize' bytes.
+ note : This function fully respect memory boundaries for properly formed
compressed data.
+ It is a bit faster than LZ4_decompress_safe().
+ However, it does not provide any protection against intentionally
modified data stream (malicious input).
+ Use this function in trusted environment only (data to decode comes
from a trusted source).
*/
-
-int LZ4_decompress_safe_partial (const char* source, char* dest, int
inputSize, int targetOutputSize, int maxOutputSize);
+int LZ4_decompress_fast (const char* source, char* dest, int originalSize);
/*
LZ4_decompress_safe_partial() :
- This function decompress a compressed block of size 'inputSize' at
position 'source'
- into output buffer 'dest' of size 'maxOutputSize'.
+ This function decompress a compressed block of size 'compressedSize' at
position 'source'
+ into destination buffer 'dest' of size 'maxDecompressedSize'.
The function tries to stop decompressing operation as soon as
'targetOutputSize' has been reached,
reducing decompression time.
- return : the number of bytes decoded in the destination buffer
(necessarily <= maxOutputSize)
+ return : the number of bytes decoded in the destination buffer
(necessarily <= maxDecompressedSize)
Note : this number can be < 'targetOutputSize' should the compressed
block to decode be smaller.
Always control how many bytes were decoded.
If the source stream is detected malformed, the function will
stop decoding and return a negative result.
This function never writes outside of output buffer, and never
reads outside of input buffer. It is therefore protected against malicious data
packets
*/
+int LZ4_decompress_safe_partial (const char* source, char* dest, int
compressedSize, int targetOutputSize, int maxDecompressedSize);
-//****************************
-// Stream Functions
-//****************************
-
-void* LZ4_create (const char* inputBuffer);
-int LZ4_compress_continue (void* LZ4_Data, const char* source, char* dest,
int inputSize);
-int LZ4_compress_limitedOutput_continue (void* LZ4_Data, const char* source,
char* dest, int inputSize, int maxOutputSize);
-char* LZ4_slideInputBuffer (void* LZ4_Data);
-int LZ4_free (void* LZ4_Data);
-
+/***********************************************
+* Streaming Compression Functions
+***********************************************/
+#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4)
+#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(long long))
/*
-These functions allow the compression of dependent blocks, where each block
benefits from prior 64 KB within preceding blocks.
-In order to achieve this, it is necessary to start creating the LZ4 Data
Structure, thanks to the function :
-
-void* LZ4_create (const char* inputBuffer);
-The result of the function is the (void*) pointer on the LZ4 Data Structure.
-This pointer will be needed in all other functions.
-If the pointer returned is NULL, then the allocation has failed, and
compression must be aborted.
-The only parameter 'const char* inputBuffer' must, obviously, point at the
beginning of input buffer.
-The input buffer must be already allocated, and size at least 192KB.
-'inputBuffer' will also be the 'const char* source' of the first block.
+ * LZ4_stream_t
+ * information structure to track an LZ4 stream.
+ * important : init this structure content before first use !
+ * note : only allocated directly the structure if you are statically linking
LZ4
+ * If you are using liblz4 as a DLL, please use below construction
methods instead.
+ */
+typedef struct { long long table[LZ4_STREAMSIZE_U64]; } LZ4_stream_t;
-All blocks are expected to lay next to each other within the input buffer,
starting from 'inputBuffer'.
-To compress each block, use either LZ4_compress_continue() or
LZ4_compress_limitedOutput_continue().
-Their behavior are identical to LZ4_compress() or LZ4_compress_limitedOutput(),
-but require the LZ4 Data Structure as their first argument, and check that
each block starts right after the previous one.
-If next block does not begin immediately after the previous one, the
compression will fail (return 0).
+/*
+ * LZ4_resetStream
+ * Use this function to init an allocated LZ4_stream_t structure
+ */
+void LZ4_resetStream (LZ4_stream_t* streamPtr);
-When it's no longer possible to lay the next block after the previous one (not
enough space left into input buffer), a call to :
-char* LZ4_slideInputBuffer(void* LZ4_Data);
-must be performed. It will typically copy the latest 64KB of input at the
beginning of input buffer.
-Note that, for this function to work properly, minimum size of an input buffer
must be 192KB.
-==> The memory position where the next input data block must start is provided
as the result of the function.
+/*
+ * LZ4_createStream will allocate and initialize an LZ4_stream_t structure
+ * LZ4_freeStream releases its memory.
+ * In the context of a DLL (liblz4), please use these methods rather than the
static struct.
+ * 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* streamPtr);
-Compression can then resume, using LZ4_compress_continue() or
LZ4_compress_limitedOutput_continue(), as usual.
+/*
+ * LZ4_loadDict
+ * Use this function to load a static dictionary into LZ4_stream.
+ * Any previous data will be forgotten, only 'dictionary' will remain in
memory.
+ * Loading a size of 0 is allowed.
+ * Return : dictionary size, in bytes (necessarily <= 64 KB)
+ */
+int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int
dictSize);
-When compression is completed, a call to LZ4_free() will release the memory
used by the LZ4 Data Structure.
-*/
+/*
+ * 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_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
LZ4_compress_fast_continue()
+ * Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if
error
+ */
+int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize);
+
+
+/************************************************
+* Streaming Decompression Functions
+************************************************/
+
+#define LZ4_STREAMDECODESIZE_U64 4
+#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned
long long))
+typedef struct { unsigned long long table[LZ4_STREAMDECODESIZE_U64]; }
LZ4_streamDecode_t;
+/*
+ * LZ4_streamDecode_t
+ * information structure to track an LZ4 stream.
+ * init this structure content using LZ4_setStreamDecode or memset() before
first use !
+ *
+ * In the context of a DLL (liblz4) please prefer usage of construction
methods below.
+ * They are more future proof, in case of a change of LZ4_streamDecode_t size
in the future.
+ * LZ4_createStreamDecode will allocate and initialize an LZ4_streamDecode_t
structure
+ * LZ4_freeStreamDecode releases its memory.
+ */
+LZ4_streamDecode_t* LZ4_createStreamDecode(void);
+int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
-int LZ4_decompress_safe_withPrefix64k (const char* source, char* dest, int
inputSize, int maxOutputSize);
-int LZ4_decompress_fast_withPrefix64k (const char* source, char* dest, int
outputSize);
+/*
+ * LZ4_setStreamDecode
+ * Use this function to instruct where to find the dictionary.
+ * Setting a size of 0 is allowed (same effect as reset).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char*
dictionary, int dictSize);
/*
-*_withPrefix64k() :
- These decoding functions work the same as their "normal name" versions,
- but can use up to 64KB of data in front of 'char* dest'.
- These functions are necessary to decode inter-dependant blocks.
+*_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)
+ 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);
-//****************************
-// Obsolete Functions
-//****************************
-
-static inline int LZ4_uncompress (const char* source, char* dest, int
outputSize) { return LZ4_decompress_fast(source, dest, outputSize); }
-static inline int LZ4_uncompress_unknownOutputSize (const char* source, char*
dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest,
isize, maxOutputSize); }
-
/*
-These functions are deprecated and should no longer be used.
-They are provided here for compatibility with existing user programs.
+Advanced decoding functions :
+*_usingDict() :
+ These decoding functions work the same as
+ 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);
+
+
+
+/**************************************
+* Obsolete Functions
+**************************************/
+/* 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
*/
+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 */
+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)
--
2.7.3
