/*
LZ4 - Fast LZ compression algorithm
- Copyright (C) 2011-2013, Yann Collet.
+ Copyright (C) 2011-2017, 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
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 homepage : http://www.lz4.org
+ - LZ4 source repository : https://github.com/lz4/lz4
*/
-#include "config.h"
+/*-************************************
+* Tuning parameters
+**************************************/
/*
-Note : this source file requires "lz4_encoder.h"
-*/
-
-//**************************************
-// 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 function will allocate memory for its hash table,
-// in memory stack (0:default, fastest), or in memory heap (1:requires memory allocation (malloc)).
-// Default allocation strategy is to use stack (HEAPMODE 0)
-// Note : explicit functions *_stack* and *_heap* are unaffected by this setting
-#define HEAPMODE 0
-
-// BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :
-// This will provide a small boost to performance for big endian cpu, but the resulting compressed stream will be incompatible with little-endian CPU.
-// You can set this option to 1 in situations where data will remain within closed environment
-// This option is useless on Little_Endian CPU (such as x86)
-//#define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1
-
-#ifdef HAVE_BIG_ENDIAN
-#define LZ4_BIG_ENDIAN 1
-#else
-#if defined(__sparc) || defined(__sparc__) \
- || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \
- || defined(__hpux) || defined(__hppa) \
- || defined(_MIPSEB) || defined(__s390__)
-// KES -- the following is not a correct assumption
-//#error "BIG Endian detected but not set"
-#endif
+ * LZ4_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()).
+ */
+#ifndef LZ4_HEAPMODE
+# define LZ4_HEAPMODE 0
#endif
-//**************************************
-// 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
-
-
-// Unaligned memory access is automatically enabled for "common" CPU, such as x86.
-// For others CPU, the compiler will be more cautious, and insert extra code to ensure aligned access is respected
-// 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
+/*
+ * ACCELERATION_DEFAULT :
+ * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
+ */
+#define ACCELERATION_DEFAULT 1
+
+
+/*-************************************
+* CPU Feature Detection
+**************************************/
+/* LZ4_FORCE_MEMORY_ACCESS
+ * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
+ * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
+ * The below switch allow to select different access method for improved performance.
+ * Method 0 (default) : use `memcpy()`. Safe and portable.
+ * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
+ * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
+ * Method 2 : direct access. This method is portable but violate C standard.
+ * It can generate buggy code on targets which assembly generation depends on alignment.
+ * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
+ * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
+ * Prefer these methods in priority order (0 > 1 > 2)
+ */
+#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */
+# if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
+# define LZ4_FORCE_MEMORY_ACCESS 2
+# elif defined(__INTEL_COMPILER) || defined(__GNUC__)
+# define LZ4_FORCE_MEMORY_ACCESS 1
+# endif
#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
+/*
+ * 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
-//**************************************
-// Compiler Options
-//**************************************
-#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L // C99
-/* "restrict" is a known keyword */
-#elif !defined restrict
-# define restrict // Disable restrict
-#endif
+/*-************************************
+* Dependency
+**************************************/
+#include "lz4.h"
+/* see also "memory routines" below */
-#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+/*-************************************
+* Compiler Options
+**************************************/
+#ifdef _MSC_VER /* Visual Studio */
+# include <intrin.h>
+# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
+# pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */
+#endif /* _MSC_VER */
-#ifdef _MSC_VER // Visual Studio
-# include <intrin.h> // For Visual 2005
-# if LZ4_ARCH64 // 64-bit
-# pragma intrinsic(_BitScanForward64) // For Visual 2005
-# pragma intrinsic(_BitScanReverse64) // For Visual 2005
+#ifndef LZ4_FORCE_INLINE
+# ifdef _MSC_VER /* Visual Studio */
+# define LZ4_FORCE_INLINE static __forceinline
# else
-# pragma intrinsic(_BitScanForward) // For Visual 2005
-# pragma intrinsic(_BitScanReverse) // For Visual 2005
-# endif
-# pragma warning(disable : 4127) // disable: C4127: conditional expression is constant
-#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
-
-#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
+# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
+# ifdef __GNUC__
+# define LZ4_FORCE_INLINE static inline __attribute__((always_inline))
+# else
+# define LZ4_FORCE_INLINE static inline
+# endif
+# else
+# define LZ4_FORCE_INLINE static
+# endif /* __STDC_VERSION__ */
+# endif /* _MSC_VER */
+#endif /* LZ4_FORCE_INLINE */
+
+#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__)
# define expect(expr,value) (__builtin_expect ((expr),(value)) )
#else
# define expect(expr,value) (expr)
#define unlikely(expr) expect((expr) != 0, 0)
-//**************************************
-// Includes
-//**************************************
-#include <stdlib.h> // for malloc
-#include <string.h> // for memset
-#include "lz4.h"
+/*-************************************
+* Memory routines
+**************************************/
+#include <stdlib.h> /* malloc, calloc, free */
+#define ALLOCATOR(n,s) calloc(n,s)
+#define FREEMEM free
+#include <string.h> /* memset, memcpy */
+#define MEM_INIT memset
-//**************************************
-// Basic Types
-//**************************************
-#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L // C99
+/*-************************************
+* Basic Types
+**************************************/
+#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
# include <stdint.h>
- typedef uint8_t BYTE;
+ typedef uint8_t BYTE;
typedef uint16_t U16;
typedef uint32_t U32;
typedef int32_t S32;
typedef uint64_t U64;
+ typedef uintptr_t uptrval;
#else
typedef unsigned char BYTE;
typedef unsigned short U16;
typedef unsigned int U32;
typedef signed int S32;
typedef unsigned long long U64;
+ typedef size_t uptrval; /* generally true, except OpenVMS-64 */
#endif
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS)
-# pragma pack(1)
+#if defined(__x86_64__)
+ typedef U64 reg_t; /* 64-bits in x32 mode */
+#else
+ typedef size_t reg_t; /* 32-bits in x32 mode */
#endif
-typedef struct _U16_S { U16 v; } U16_S;
-typedef struct _U32_S { U32 v; } U32_S;
-typedef struct _U64_S { U64 v; } U64_S;
+/*-************************************
+* Reading and writing into memory
+**************************************/
+static unsigned LZ4_isLittleEndian(void)
+{
+ const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */
+ return one.c[0];
+}
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS)
-# pragma pack()
-#endif
-#define A64(x) (((U64_S *)(x))->v)
-#define A32(x) (((U32_S *)(x))->v)
-#define A16(x) (((U16_S *)(x))->v)
+#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2)
+/* lie to the compiler about data alignment; use with caution */
+
+static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; }
+static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; }
+static reg_t LZ4_read_ARCH(const void* memPtr) { return *(const reg_t*) memPtr; }
+
+static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; }
+static void LZ4_write32(void* memPtr, U32 value) { *(U32*)memPtr = value; }
+
+#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1)
+/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
+/* currently only defined for gcc and icc */
+typedef union { U16 u16; U32 u32; reg_t uArch; } __attribute__((packed)) unalign;
-//**************************************
-// Constants
-//**************************************
-#define HASHTABLESIZE (1 << MEMORY_USAGE)
+static U16 LZ4_read16(const void* ptr) { return ((const unalign*)ptr)->u16; }
+static U32 LZ4_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
+static reg_t LZ4_read_ARCH(const void* ptr) { return ((const unalign*)ptr)->uArch; }
+
+static void LZ4_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; }
+static void LZ4_write32(void* memPtr, U32 value) { ((unalign*)memPtr)->u32 = value; }
+
+#else /* safe and portable access through memcpy() */
+
+static U16 LZ4_read16(const void* memPtr)
+{
+ U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
+}
+static U32 LZ4_read32(const void* memPtr)
+{
+ U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
+}
+
+static reg_t LZ4_read_ARCH(const void* memPtr)
+{
+ reg_t val; memcpy(&val, memPtr, sizeof(val)); return val;
+}
+
+static void LZ4_write16(void* memPtr, U16 value)
+{
+ memcpy(memPtr, &value, sizeof(value));
+}
+
+static void LZ4_write32(void* memPtr, U32 value)
+{
+ memcpy(memPtr, &value, sizeof(value));
+}
+
+#endif /* LZ4_FORCE_MEMORY_ACCESS */
+
+
+static U16 LZ4_readLE16(const void* memPtr)
+{
+ if (LZ4_isLittleEndian()) {
+ return LZ4_read16(memPtr);
+ } else {
+ const BYTE* p = (const BYTE*)memPtr;
+ return (U16)((U16)p[0] + (p[1]<<8));
+ }
+}
+
+static void LZ4_writeLE16(void* memPtr, U16 value)
+{
+ if (LZ4_isLittleEndian()) {
+ LZ4_write16(memPtr, value);
+ } else {
+ BYTE* p = (BYTE*)memPtr;
+ p[0] = (BYTE) value;
+ p[1] = (BYTE)(value>>8);
+ }
+}
+
+static void LZ4_copy8(void* dst, const void* src)
+{
+ memcpy(dst,src,8);
+}
+
+/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */
+static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
+{
+ BYTE* d = (BYTE*)dstPtr;
+ const BYTE* s = (const BYTE*)srcPtr;
+ BYTE* const e = (BYTE*)dstEnd;
+
+ do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e);
+}
+
+
+/*-************************************
+* Common Constants
+**************************************/
#define MINMATCH 4
-#define COPYLENGTH 8
+#define WILDCOPYLENGTH 8
#define LASTLITERALS 5
-#define MFLIMIT (COPYLENGTH+MINMATCH)
-#define MINLENGTH (MFLIMIT+1)
+#define MFLIMIT (WILDCOPYLENGTH+MINMATCH)
+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)
#define RUN_MASK ((1U<<RUN_BITS)-1)
-//**************************************
-// Architecture-specific macros
-//**************************************
-#if LZ4_ARCH64 // 64-bit
-# define STEPSIZE 8
-# define UARCH U64
-# define AARCH A64
-# define LZ4_COPYSTEP(s,d) A64(d) = A64(s); d+=8; s+=8;
-# define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d)
-# define LZ4_SECURECOPY(s,d,e) if (d<e) LZ4_WILDCOPY(s,d,e)
-# define HTYPE U32
-# define INITBASE(base) const BYTE* const base = ip
-#else // 32-bit
-# define STEPSIZE 4
-# define UARCH U32
-# define AARCH A32
-# define LZ4_COPYSTEP(s,d) A32(d) = A32(s); d+=4; s+=4;
-# define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d); LZ4_COPYSTEP(s,d);
-# define LZ4_SECURECOPY LZ4_WILDCOPY
-# define HTYPE const BYTE*
-# define INITBASE(base) const int base = 0
-#endif
+/*-************************************
+* Error detection
+**************************************/
+#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
-#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; }
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2)
+# include <stdio.h>
+# define DEBUGLOG(l, ...) { \
+ if (l<=LZ4_DEBUG) { \
+ fprintf(stderr, __FILE__ ": "); \
+ fprintf(stderr, __VA_ARGS__); \
+ fprintf(stderr, " \n"); \
+ } }
+#else
+# define DEBUGLOG(l, ...) {} /* disabled */
#endif
-//**************************************
-// Macros
-//**************************************
-#define LZ4_WILDCOPY(s,d,e) do { LZ4_COPYPACKET(s,d) } while (d<e);
-#define LZ4_BLINDCOPY(s,d,l) { BYTE* e=(d)+(l); LZ4_WILDCOPY(s,d,e); d=e; }
-
-
-//****************************
-// Private functions
-//****************************
-#if LZ4_ARCH64
-
-static 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 & -val) * 0x0218A392CDABBD3F)) >> 58];
- #endif
-#endif
+/*-************************************
+* Common functions
+**************************************/
+static unsigned LZ4_NbCommonBytes (register reg_t val)
+{
+ if (LZ4_isLittleEndian()) {
+ if (sizeof(val)==8) {
+# 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__) || (defined(__GNUC__) && (__GNUC__>=3))) && !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__) || (defined(__GNUC__) && (__GNUC__>=3))) && !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 (sizeof(val)==8) {
+# 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__) || (defined(__GNUC__) && (__GNUC__>=3))) && !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__) || (defined(__GNUC__) && (__GNUC__>=3))) && !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
+ }
+ }
}
-#else
+#define STEPSIZE sizeof(reg_t)
+static unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit)
+{
+ const BYTE* const pStart = pIn;
+
+ while (likely(pIn<pInLimit-(STEPSIZE-1))) {
+ reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+ if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; }
+ pIn += LZ4_NbCommonBytes(diff);
+ return (unsigned)(pIn - pStart);
+ }
+
+ if ((STEPSIZE==8) && (pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; }
+ if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; }
+ if ((pIn<pInLimit) && (*pMatch == *pIn)) pIn++;
+ return (unsigned)(pIn - pStart);
+}
+
+
+#ifndef LZ4_COMMONDEFS_ONLY
+/*-************************************
+* Local Constants
+**************************************/
+static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT-1));
+static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression run slower on incompressible data */
+
+
+/*-************************************
+* Local Structures and types
+**************************************/
+typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { byPtr, byU32, byU16 } tableType_t;
+
+typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
+
+typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
+typedef enum { full = 0, partial = 1 } earlyEnd_directive;
+
+
+/*-************************************
+* Local Utils
+**************************************/
+int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; }
+const char* LZ4_versionString(void) { return LZ4_VERSION_STRING; }
+int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
+int LZ4_sizeofState() { return LZ4_STREAMSIZE; }
-static inline int LZ4_NbCommonBytes (register U32 val)
+
+/*-******************************
+* Compression functions
+********************************/
+static U32 LZ4_hash4(U32 sequence, tableType_t const tableType)
{
-#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
+ if (tableType == byU16)
+ return ((sequence * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
+ else
+ return ((sequence * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
+}
+
+static U32 LZ4_hash5(U64 sequence, tableType_t const tableType)
+{
+ static const U64 prime5bytes = 889523592379ULL;
+ static const U64 prime8bytes = 11400714785074694791ULL;
+ const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG;
+ if (LZ4_isLittleEndian())
+ return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
+ else
+ return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
+}
+
+LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType)
+{
+ if ((sizeof(reg_t)==8) && (tableType != byU16)) return LZ4_hash5(LZ4_read_ARCH(p), tableType);
+ return LZ4_hash4(LZ4_read32(p), tableType);
+}
+
+static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t const tableType, const BYTE* srcBase)
+{
+ switch (tableType)
+ {
+ case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; }
+ case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; }
+ case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; }
+ }
+}
+
+LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+ LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+}
+
+static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; }
+ if (tableType == byU32) { const U32* const hashTable = (U32*) tableBase; return hashTable[h] + srcBase; }
+ { const U16* const hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
+}
+
+LZ4_FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+ return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
+}
+
+
+/** LZ4_compress_generic() :
+ inlined, to ensure branches are decided at compilation time */
+LZ4_FORCE_INLINE int LZ4_compress_generic(
+ LZ4_stream_t_internal* const cctx,
+ 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)
+{
+ const BYTE* ip = (const BYTE*) source;
+ const BYTE* base;
+ const BYTE* lowLimit;
+ const BYTE* const lowRefLimit = ip - cctx->dictSize;
+ const BYTE* const dictionary = cctx->dictionary;
+ const BYTE* const dictEnd = dictionary + cctx->dictSize;
+ const ptrdiff_t dictDelta = dictEnd - (const BYTE*)source;
+ const BYTE* anchor = (const BYTE*) source;
+ const BYTE* const iend = ip + inputSize;
+ const BYTE* const mflimit = iend - MFLIMIT;
+ const BYTE* const matchlimit = iend - LASTLITERALS;
+
+ BYTE* op = (BYTE*) dest;
+ BYTE* const olimit = op + maxOutputSize;
+
+ U32 forwardH;
+
+ /* Init conditions */
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported inputSize, too large (or negative) */
+ switch(dict)
+ {
+ case noDict:
+ default:
+ base = (const BYTE*)source;
+ lowLimit = (const BYTE*)source;
+ break;
+ case withPrefix64k:
+ base = (const BYTE*)source - cctx->currentOffset;
+ lowLimit = (const BYTE*)source - cctx->dictSize;
+ break;
+ case usingExtDict:
+ base = (const BYTE*)source - cctx->currentOffset;
+ lowLimit = (const BYTE*)source;
+ break;
+ }
+ if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
+ if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
+
+ /* First Byte */
+ LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; ) {
+ ptrdiff_t refDelta = 0;
+ const BYTE* match;
+ BYTE* token;
+
+ /* Find a match */
+ { const BYTE* forwardIp = ip;
+ unsigned step = 1;
+ unsigned searchMatchNb = acceleration << LZ4_skipTrigger;
+ do {
+ U32 const h = forwardH;
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+ if (unlikely(forwardIp > mflimit)) goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, cctx->hashTable, 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, cctx->hashTable, tableType, base);
+
+ } while ( ((dictIssue==dictSmall) ? (match < lowRefLimit) : 0)
+ || ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match+refDelta) != LZ4_read32(ip)) );
+ }
+
+ /* Catch up */
+ while (((ip>anchor) & (match+refDelta > lowLimit)) && (unlikely(ip[-1]==match[refDelta-1]))) { ip--; match--; }
+
+ /* Encode Literals */
+ { unsigned const litLength = (unsigned)(ip - anchor);
+ token = op++;
+ if ((outputLimited) && /* Check output buffer overflow */
+ (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)))
+ return 0;
+ if (litLength >= RUN_MASK) {
+ int len = (int)litLength-RUN_MASK;
+ *token = (RUN_MASK<<ML_BITS);
+ for(; len >= 255 ; len-=255) *op++ = 255;
+ *op++ = (BYTE)len;
+ }
+ else *token = (BYTE)(litLength<<ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op+litLength);
+ op+=litLength;
+ }
+
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
+
+ /* Encode MatchLength */
+ { unsigned matchCode;
+
+ if ((dict==usingExtDict) && (lowLimit==dictionary)) {
+ const BYTE* limit;
+ match += refDelta;
+ limit = ip + (dictEnd-match);
+ if (limit > matchlimit) limit = matchlimit;
+ matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, limit);
+ ip += MINMATCH + matchCode;
+ if (ip==limit) {
+ unsigned const more = LZ4_count(ip, (const BYTE*)source, matchlimit);
+ matchCode += more;
+ ip += more;
+ }
+ } else {
+ matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
+ ip += MINMATCH + matchCode;
+ }
+
+ if ( outputLimited && /* Check output buffer overflow */
+ (unlikely(op + (1 + LASTLITERALS) + (matchCode>>8) > olimit)) )
+ return 0;
+ if (matchCode >= ML_MASK) {
+ *token += ML_MASK;
+ matchCode -= ML_MASK;
+ LZ4_write32(op, 0xFFFFFFFF);
+ while (matchCode >= 4*255) op+=4, LZ4_write32(op, 0xFFFFFFFF), matchCode -= 4*255;
+ op += matchCode / 255;
+ *op++ = (BYTE)(matchCode % 255);
+ } else
+ *token += (BYTE)(matchCode);
+ }
+
+ anchor = ip;
+
+ /* Test end of chunk */
+ if (ip > mflimit) break;
+
+ /* Fill table */
+ LZ4_putPosition(ip-2, cctx->hashTable, tableType, base);
+
+ /* Test next position */
+ match = LZ4_getPosition(ip, cctx->hashTable, tableType, base);
+ if (dict==usingExtDict) {
+ if (match < (const BYTE*)source) {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ } else {
+ refDelta = 0;
+ lowLimit = (const BYTE*)source;
+ } }
+ LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+ if ( ((dictIssue==dictSmall) ? (match>=lowRefLimit) : 1)
+ && (match+MAX_DISTANCE>=ip)
+ && (LZ4_read32(match+refDelta)==LZ4_read32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
+
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
+ }
+
+_last_literals:
+ /* Encode Last Literals */
+ { size_t const lastRun = (size_t)(iend - anchor);
+ if ( (outputLimited) && /* Check output buffer overflow */
+ ((op - (BYTE*)dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize) )
+ return 0;
+ if (lastRun >= RUN_MASK) {
+ size_t accumulator = lastRun - RUN_MASK;
+ *op++ = RUN_MASK << ML_BITS;
+ for(; accumulator >= 255 ; accumulator-=255) *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ } else {
+ *op++ = (BYTE)(lastRun<<ML_BITS);
+ }
+ memcpy(op, anchor, lastRun);
+ op += lastRun;
+ }
+
+ /* End */
+ return (int) (((char*)op)-dest);
+}
+
+
+int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
+{
+ LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse;
+ 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(ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(ctx, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+ } else {
+ 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, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+ }
}
+
+int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
+{
+#if (LZ4_HEAPMODE)
+ void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+#else
+ LZ4_stream_t ctx;
+ void* const ctxPtr = &ctx;
#endif
+ int const result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
+#if (LZ4_HEAPMODE)
+ FREEMEM(ctxPtr);
+#endif
+ return result;
+}
-//******************************
-// Compression functions
-//******************************
-/*
-int LZ4_compress_stack(
- const char* source,
- char* dest,
- int inputSize)
-
-Compress 'inputSize' bytes from 'source' into an output buffer 'dest'.
-Destination buffer must be already allocated, and sized at a minimum of LZ4_compressBound(inputSize).
-return : the number of bytes written in buffer 'dest'
-*/
-#define FUNCTION_NAME LZ4_compress_stack
-#include "lz4_encoder.h"
+int LZ4_compress_default(const char* source, char* dest, int inputSize, int maxOutputSize)
+{
+ return LZ4_compress_fast(source, dest, inputSize, maxOutputSize, 1);
+}
-/*
-int LZ4_compress_stack_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);
-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.
-return : the number of bytes written in buffer 'dest', or 0 if the compression fails
-*/
-#define FUNCTION_NAME LZ4_compress_stack_limitedOutput
-#define LIMITED_OUTPUT
-#include "lz4_encoder.h"
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, maxOutputSize, limitedOutput, sizeof(void*)==8 ? byU32 : byPtr, noDict, noDictIssue, acceleration);
+}
-/*
-int LZ4_compress64k_stack(
- const char* source,
- char* dest,
- int inputSize)
-
-Compress 'inputSize' bytes from 'source' into an output buffer 'dest'.
-This function compresses better than LZ4_compress_stack(), on the condition that
-'inputSize' must be < to LZ4_64KLIMIT, or the function will fail.
-Destination buffer must be already allocated, and sized at a minimum of LZ4_compressBound(inputSize).
-return : the number of bytes written in buffer 'dest', or 0 if compression fails
-*/
-#define FUNCTION_NAME LZ4_compress64k_stack
-#define COMPRESS_64K
-#include "lz4_encoder.h"
+/*-******************************
+* *_destSize() variant
+********************************/
+static int LZ4_compress_destSize_generic(
+ LZ4_stream_t_internal* 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->hashTable, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; ) {
+ const BYTE* match;
+ BYTE* token;
+
+ /* Find a match */
+ { const BYTE* forwardIp = ip;
+ unsigned step = 1;
+ unsigned searchMatchNb = 1 << LZ4_skipTrigger;
+
+ do {
+ U32 h = forwardH;
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+ if (unlikely(forwardIp > mflimit)) goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, ctx->hashTable, tableType, base);
+ forwardH = LZ4_hashPosition(forwardIp, tableType);
+ LZ4_putPositionOnHash(ip, h, ctx->hashTable, tableType, base);
+
+ } while ( ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match) != LZ4_read32(ip)) );
+ }
-/*
-int LZ4_compress64k_stack_limitedOutput(
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize)
+ /* Catch up */
+ while ((ip>anchor) && (match > lowLimit) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; }
-Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'.
-This function compresses better than LZ4_compress_stack_limitedOutput(), on the condition that
-'inputSize' must be < to LZ4_64KLIMIT, or the function will fail.
-If it cannot achieve it, compression will stop, and result of the function will be zero.
-return : the number of bytes written in buffer 'dest', or 0 if the compression fails
-*/
-#define FUNCTION_NAME LZ4_compress64k_stack_limitedOutput
-#define COMPRESS_64K
-#define LIMITED_OUTPUT
-#include "lz4_encoder.h"
+ /* 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;
+ }
-/*
-void* LZ4_createHeapMemory();
-int LZ4_freeHeapMemory(void* ctx);
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip-match)); op+=2;
-Used to allocate and free hashTable memory
-to be used by the LZ4_compress_heap* family of functions.
-LZ4_createHeapMemory() returns NULL is memory allocation fails.
-*/
-void* LZ4_create() { return malloc(HASHTABLESIZE); }
-int LZ4_free(void* ctx) { free(ctx); return 0; }
+ /* Encode MatchLength */
+ { size_t matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit);
+ if (op + ((matchLength+240)/255) > oMaxMatch) {
+ /* Match description too long : reduce it */
+ matchLength = (15-1) + (oMaxMatch-op) * 255;
+ }
+ ip += MINMATCH + matchLength;
-/*
-int LZ4_compress_heap(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize)
-
-Compress 'inputSize' bytes from 'source' into an output buffer 'dest'.
-The memory used for compression must be created by LZ4_createHeapMemory() and provided by pointer 'ctx'.
-Destination buffer must be already allocated, and sized at a minimum of LZ4_compressBound(inputSize).
-return : the number of bytes written in buffer 'dest'
-*/
-#define FUNCTION_NAME LZ4_compress_heap
-#define USE_HEAPMEMORY
-#include "lz4_encoder.h"
+ 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;
-/*
-int LZ4_compress_heap_limitedOutput(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize)
+ /* Test end of block */
+ if (ip > mflimit) break;
+ if (op > oMaxSeq) break;
-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.
-The memory used for compression must be created by LZ4_createHeapMemory() and provided by pointer 'ctx'.
-return : the number of bytes written in buffer 'dest', or 0 if the compression fails
-*/
-#define FUNCTION_NAME LZ4_compress_heap_limitedOutput
-#define LIMITED_OUTPUT
-#define USE_HEAPMEMORY
-#include "lz4_encoder.h"
+ /* Fill table */
+ LZ4_putPosition(ip-2, ctx->hashTable, tableType, base);
+ /* Test next position */
+ match = LZ4_getPosition(ip, ctx->hashTable, tableType, base);
+ LZ4_putPosition(ip, ctx->hashTable, tableType, base);
+ if ( (match+MAX_DISTANCE>=ip)
+ && (LZ4_read32(match)==LZ4_read32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
-/*
-int LZ4_compress64k_heap(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize)
-
-Compress 'inputSize' bytes from 'source' into an output buffer 'dest'.
-The memory used for compression must be created by LZ4_createHeapMemory() and provided by pointer 'ctx'.
-'inputSize' must be < to LZ4_64KLIMIT, or the function will fail.
-Destination buffer must be already allocated, and sized at a minimum of LZ4_compressBound(inputSize).
-return : the number of bytes written in buffer 'dest'
-*/
-#define FUNCTION_NAME LZ4_compress64k_heap
-#define COMPRESS_64K
-#define USE_HEAPMEMORY
-#include "lz4_encoder.h"
+ /* 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;
+ }
-/*
-int LZ4_compress64k_heap_limitedOutput(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize)
+ /* End */
+ *srcSizePtr = (int) (((const char*)ip)-src);
+ return (int) (((char*)op)-dst);
+}
-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.
-The memory used for compression must be created by LZ4_createHeapMemory() and provided by pointer 'ctx'.
-'inputSize' must be < to LZ4_64KLIMIT, or the function will fail.
-return : the number of bytes written in buffer 'dest', or 0 if the compression fails
-*/
-#define FUNCTION_NAME LZ4_compress64k_heap_limitedOutput
-#define COMPRESS_64K
-#define LIMITED_OUTPUT
-#define USE_HEAPMEMORY
-#include "lz4_encoder.h"
+
+static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize)
+{
+ LZ4_resetStream(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->internal_donotuse, src, dst, srcSizePtr, targetDstSize, byU16);
+ else
+ return LZ4_compress_destSize_generic(&state->internal_donotuse, src, dst, srcSizePtr, targetDstSize, sizeof(void*)==8 ? byU32 : byPtr);
+ }
+}
-int LZ4_compress(const char* source, char* dest, int inputSize)
+int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize)
{
-#if HEAPMODE
- void* ctx = LZ4_create();
- int result;
- if (ctx == NULL) return 0; // Failed allocation => compression not done
- if (inputSize < LZ4_64KLIMIT)
- result = LZ4_compress64k_heap(ctx, source, dest, inputSize);
- else result = LZ4_compress_heap(ctx, source, dest, inputSize);
- LZ4_free(ctx);
- return result;
+#if (LZ4_HEAPMODE)
+ LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
#else
- if (inputSize < (int)LZ4_64KLIMIT) return LZ4_compress64k_stack(source, dest, inputSize);
- return LZ4_compress_stack(source, dest, inputSize);
+ LZ4_stream_t ctxBody;
+ LZ4_stream_t* ctx = &ctxBody;
#endif
+
+ int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize);
+
+#if (LZ4_HEAPMODE)
+ FREEMEM(ctx);
+#endif
+ return result;
+}
+
+
+
+/*-******************************
+* Streaming functions
+********************************/
+
+LZ4_stream_t* LZ4_createStream(void)
+{
+ LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(8, LZ4_STREAMSIZE_U64);
+ LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
+ LZ4_resetStream(lz4s);
+ return lz4s;
+}
+
+void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
+{
+ MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
+
+int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
+{
+ if (!LZ4_stream) return 0; /* support free on NULL */
+ FREEMEM(LZ4_stream);
+ return (0);
+}
+
+
+#define HASH_UNIT sizeof(reg_t)
+int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
+{
+ LZ4_stream_t_internal* dict = &LZ4_dict->internal_donotuse;
+ const BYTE* p = (const BYTE*)dictionary;
+ const BYTE* const dictEnd = p + dictSize;
+ const BYTE* base;
+
+ if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized structure, or reuse overflow */
+ LZ4_resetStream(LZ4_dict);
+
+ if (dictSize < (int)HASH_UNIT) {
+ dict->dictionary = NULL;
+ dict->dictSize = 0;
+ return 0;
+ }
+
+ if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB;
+ dict->currentOffset += 64 KB;
+ base = p - dict->currentOffset;
+ dict->dictionary = p;
+ dict->dictSize = (U32)(dictEnd - p);
+ dict->currentOffset += dict->dictSize;
+
+ while (p <= dictEnd-HASH_UNIT) {
+ LZ4_putPosition(p, dict->hashTable, byU32, base);
+ p+=3;
+ }
+
+ return dict->dictSize;
+}
+
+
+static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
+{
+ if ((LZ4_dict->currentOffset > 0x80000000) ||
+ ((uptrval)LZ4_dict->currentOffset > (uptrval)src)) { /* address space overflow */
+ /* rescale hash table */
+ U32 const delta = LZ4_dict->currentOffset - 64 KB;
+ const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
+ int i;
+ for (i=0; i<LZ4_HASH_SIZE_U32; i++) {
+ if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0;
+ else LZ4_dict->hashTable[i] -= delta;
+ }
+ LZ4_dict->currentOffset = 64 KB;
+ if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB;
+ LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
+ }
+}
+
+
+int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
+{
+ LZ4_stream_t_internal* streamPtr = &LZ4_stream->internal_donotuse;
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+
+ const BYTE* smallest = (const BYTE*) source;
+ if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */
+ if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd;
+ LZ4_renormDictT(streamPtr, smallest);
+ if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
+
+ /* Check overlapping input/dictionary space */
+ { const BYTE* sourceEnd = (const BYTE*) source + inputSize;
+ if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) {
+ streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
+ if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB;
+ if (streamPtr->dictSize < 4) streamPtr->dictSize = 0;
+ streamPtr->dictionary = dictEnd - streamPtr->dictSize;
+ }
+ }
+
+ /* prefix mode : source data follows dictionary */
+ if (dictEnd == (const BYTE*)source) {
+ int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, dictSmall, acceleration);
+ else
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, noDictIssue, acceleration);
+ streamPtr->dictSize += (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+
+ /* external dictionary mode */
+ { int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, dictSmall, acceleration);
+ else
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, noDictIssue, acceleration);
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
}
-int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
+/* Hidden debug function, to force external dictionary mode */
+int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize)
{
-#if HEAPMODE
- void* ctx = LZ4_create();
+ LZ4_stream_t_internal* streamPtr = &LZ4_dict->internal_donotuse;
int result;
- if (ctx == NULL) return 0; // Failed allocation => compression not done
- if (inputSize < LZ4_64KLIMIT)
- result = LZ4_compress64k_heap_limitedOutput(ctx, source, dest, inputSize, maxOutputSize);
- else result = LZ4_compress_heap_limitedOutput(ctx, source, dest, inputSize, maxOutputSize);
- LZ4_free(ctx);
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+
+ const BYTE* smallest = dictEnd;
+ if (smallest > (const BYTE*) source) smallest = (const BYTE*) source;
+ LZ4_renormDictT(streamPtr, smallest);
+
+ result = LZ4_compress_generic(streamPtr, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
+
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+
return result;
-#else
- if (inputSize < (int)LZ4_64KLIMIT) return LZ4_compress64k_stack_limitedOutput(source, dest, inputSize, maxOutputSize);
- return LZ4_compress_stack_limitedOutput(source, dest, inputSize, maxOutputSize);
-#endif
}
-//****************************
-// Decompression functions
-//****************************
+/*! 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* LZ4_dict, char* safeBuffer, int dictSize)
+{
+ LZ4_stream_t_internal* const dict = &LZ4_dict->internal_donotuse;
+ const BYTE* const previousDictEnd = dict->dictionary + dict->dictSize;
+
+ if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a dictionary > 64 KB */
+ if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize;
+
+ memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+ dict->dictionary = (const BYTE*)safeBuffer;
+ dict->dictSize = (U32)dictSize;
-typedef enum { noPrefix = 0, withPrefix = 1 } prefix64k_directive;
-typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } end_directive;
-typedef enum { full = 0, partial = 1 } exit_directive;
+ return 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.
-static inline int LZ4_decompress_generic(
- const char* source,
- char* dest,
- int inputSize, //
- int outputSize, // OutputSize must be != 0; 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
+/*-*****************************
+* Decompression functions
+*******************************/
+/*! LZ4_decompress_generic() :
+ * This generic decompression function cover all use cases.
+ * It shall be instantiated several times, using different sets of directives
+ * Note that it is important this generic function is really inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
+LZ4_FORCE_INLINE int LZ4_decompress_generic(
+ const char* const source,
+ char* const dest,
+ int inputSize,
+ int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */
+
+ int endOnInput, /* endOnOutputSize, endOnInputSize */
+ int partialDecoding, /* full, partial */
+ int targetOutputSize, /* only used if partialDecoding==partial */
+ int dict, /* noDict, withPrefix64k, usingExtDict */
+ const BYTE* const lowPrefix, /* == dest when no prefix */
+ 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;
- size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
-#if LZ4_ARCH64
- size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
-#endif
+ const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize;
+ const unsigned dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4};
+ const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
+ const int safeDecode = (endOnInput==endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
- // Special case
- if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; // targetOutputSize too large, better decode everything
- if unlikely(outputSize==0) goto _output_error; // Empty output buffer
+ /* Special cases */
+ if ((partialDecoding) && (oexit > oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */
+ if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
+ if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1);
- // Main Loop
- while (1)
- {
- unsigned token;
+ /* Main Loop : decode sequences */
+ while (1) {
size_t length;
-
- // get runlength
- token = *ip++;
- if ((length=(token>>ML_BITS)) == RUN_MASK)
- {
- unsigned s=255;
- while (((endOnInput)?ip<iend:1) && (s==255))
- {
+ const BYTE* match;
+ size_t offset;
+
+ /* get literal length */
+ unsigned const token = *ip++;
+ if ((length=(token>>ML_BITS)) == RUN_MASK) {
+ unsigned s;
+ do {
s = *ip++;
length += s;
- }
+ } while ( likely(endOnInput ? ip<iend-RUN_MASK : 1) & (s==255) );
+ if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)(op))) goto _output_error; /* overflow detection */
+ if ((safeDecode) && unlikely((uptrval)(ip)+length<(uptrval)(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 ( ((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) )
+ || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH)) )
{
- if (partialDecoding)
- {
- if (cpy > oend) goto _output_error; // Error : write attempt beyond end of output buffer
- if ((endOnInput) && (ip+length > iend)) goto _output_error; // Error : read attempt beyond end of input buffer
- }
- else
- {
- if ((!endOnInput) && (cpy != oend)) goto _output_error; // Error : block decoding must stop exactly there, due to parsing restrictions
- if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; // Error : not enough place for another match (min 4) + 5 literals
+ if (partialDecoding) {
+ if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */
+ if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */
+ } else {
+ if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */
+ if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */
}
memcpy(op, ip, length);
ip += length;
op += length;
- break; // Necessarily EOF, due to parsing restrictions
+ break; /* Necessarily EOF, due to parsing restrictions */
}
- LZ4_WILDCOPY(ip, op, cpy); ip -= (op-cpy); 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 matchlength
- if ((length=(token&ML_MASK)) == ML_MASK)
- {
- while (endOnInput ? ip<iend-(LASTLITERALS+1) : 1) // A minimum nb of input bytes must remain for LASTLITERALS + token
- {
- unsigned s = *ip++;
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length; op = cpy;
+
+ /* get offset */
+ offset = LZ4_readLE16(ip); ip+=2;
+ match = op - offset;
+ if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside buffers */
+ LZ4_write32(op, (U32)offset); /* costs ~1%; silence an msan warning when offset==0 */
+
+ /* get matchlength */
+ length = token & ML_MASK;
+ if (length == ML_MASK) {
+ unsigned s;
+ do {
+ s = *ip++;
+ if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error;
length += s;
- if (s==255) continue;
- break;
- }
+ } while (s==255);
+ if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) goto _output_error; /* overflow detection */
}
-
- // copy repeated sequence
- if unlikely((op-ref)<STEPSIZE)
- {
-#if LZ4_ARCH64
- size_t dec64 = dec64table[op-ref];
-#else
- const size_t dec64 = 0;
-#endif
- 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(ref,op); }
- cpy = op + length - (STEPSIZE-4);
-
- if unlikely(cpy>oend-(COPYLENGTH)-(STEPSIZE-4))
- {
- if (cpy > oend-LASTLITERALS) goto _output_error; // Error : last 5 bytes must be literals
- LZ4_SECURECOPY(ref, op, (oend-COPYLENGTH));
- while(op<cpy) *op++=*ref++;
- op=cpy;
+ 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 */
+ memmove(op, dictEnd - (lowPrefix-match), length);
+ op += length;
+ } else {
+ /* match encompass external dictionary and current block */
+ size_t const copySize = (size_t)(lowPrefix-match);
+ size_t const restSize = length - copySize;
+ memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+ if (restSize > (size_t)(op-lowPrefix)) { /* overlap copy */
+ BYTE* const endOfMatch = op + restSize;
+ const BYTE* copyFrom = lowPrefix;
+ while (op < endOfMatch) *op++ = *copyFrom++;
+ } else {
+ memcpy(op, lowPrefix, restSize);
+ op += restSize;
+ } }
continue;
}
- LZ4_WILDCOPY(ref, op, cpy);
- op=cpy; // correction
+
+ /* copy match within block */
+ cpy = op + length;
+ if (unlikely(offset<8)) {
+ const int dec64 = dec64table[offset];
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += dec32table[offset];
+ memcpy(op+4, match, 4);
+ match -= dec64;
+ } else { LZ4_copy8(op, match); match+=8; }
+ op += 8;
+
+ if (unlikely(cpy>oend-12)) {
+ BYTE* const oCopyLimit = oend-(WILDCOPYLENGTH-1);
+ if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last LASTLITERALS bytes must be literals (uncompressed) */
+ if (op < oCopyLimit) {
+ LZ4_wildCopy(op, match, oCopyLimit);
+ match += oCopyLimit - op;
+ op = oCopyLimit;
+ }
+ while (op<cpy) *op++ = *match++;
+ } else {
+ LZ4_copy8(op, match);
+ if (length>16) LZ4_wildCopy(op+8, match+8, 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 compressedSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, full, 0, noDict, (BYTE*)dest, NULL, 0);
+}
+
+int LZ4_decompress_safe_partial(const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, partial, targetOutputSize, noDict, (BYTE*)dest, NULL, 0);
+}
+
+int LZ4_decompress_fast(const char* source, char* dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, (BYTE*)(dest - 64 KB), NULL, 64 KB);
+}
+
+
+/*===== streaming decompression functions =====*/
+
+LZ4_streamDecode_t* LZ4_createStreamDecode(void)
+{
+ LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(1, sizeof(LZ4_streamDecode_t));
+ return lz4s;
+}
+
+int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream)
+{
+ if (!LZ4_stream) return 0; /* support free on NULL */
+ FREEMEM(LZ4_stream);
+ return 0;
+}
+
+/*!
+ * LZ4_setStreamDecode() :
+ * Use this function to instruct where to find the dictionary.
+ * This function is not necessary if previous data is still available where it was decoded.
+ * Loading a size of 0 is allowed (same effect as no dictionary).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse;
+ 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->internal_donotuse;
+ 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->internal_donotuse;
+ 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 = lz4sd->prefixEnd - 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
+*/
+
+LZ4_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_safe(const char* source, char* dest, int inputSize, int maxOutputSize)
+int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, noPrefix, full, 0);
+ return LZ4_decompress_usingDict_generic(source, dest, 0, originalSize, 0, dictStart, dictSize);
}
-int LZ4_decompress_fast(const char* source, char* dest, int outputSize)
+/* 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, 0, outputSize, endOnOutputSize, noPrefix, full, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize);
}
-int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int inputSize, int maxOutputSize)
+
+/*=*************************************************
+* 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* lz4ds, BYTE* base)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, withPrefix, full, 0);
+ MEM_INIT(lz4ds, 0, sizeof(LZ4_stream_t));
+ lz4ds->internal_donotuse.bufferStart = base;
}
-int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int outputSize)
+int LZ4_resetStreamState(void* state, char* inputBuffer)
{
- return LZ4_decompress_generic(source, dest, 0, outputSize, endOnOutputSize, withPrefix, full, 0);
+ if ((((uptrval)state) & 3) != 0) return 1; /* Error : pointer is not aligned on 4-bytes boundary */
+ LZ4_init((LZ4_stream_t*)state, (BYTE*)inputBuffer);
+ return 0;
}
-int LZ4_decompress_safe_partial(const char* source, char* dest, int inputSize, int targetOutputSize, int maxOutputSize)
+void* LZ4_create (char* inputBuffer)
{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, noPrefix, partial, targetOutputSize);
+ LZ4_stream_t* lz4ds = (LZ4_stream_t*)ALLOCATOR(8, sizeof(LZ4_stream_t));
+ LZ4_init (lz4ds, (BYTE*)inputBuffer);
+ return lz4ds;
}
+
+char* LZ4_slideInputBuffer (void* LZ4_Data)
+{
+ LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)LZ4_Data)->internal_donotuse;
+ 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 */
/*
- LZ4 - Fast LZ compression algorithm
- Header File
- Copyright (C) 2011-2013, Yann Collet.
+ * LZ4 - Fast LZ compression algorithm
+ * Header File
+ * Copyright (C) 2011-2017, 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
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 homepage : http://www.lz4.org
+ - LZ4 source repository : https://github.com/lz4/lz4
*/
-#pragma once
-
#if defined (__cplusplus)
extern "C" {
#endif
+#ifndef LZ4_H_2983827168210
+#define LZ4_H_2983827168210
-//**************************************
-// Compiler Options
-//**************************************
-#if defined(_MSC_VER) && !defined(__cplusplus) // Visual Studio
-# define inline __forceinline // Visual C is not C99, but supports some kind of inline. Note : we *do* want to force inline
-#endif
+/* --- Dependency --- */
+#include <stddef.h> /* size_t */
+
+
+/**
+ Introduction
+ LZ4 is lossless compression algorithm, providing compression speed at 400 MB/s per core,
+ scalable with multi-cores CPU. It features an extremely fast decoder, with speed in
+ multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.
-//****************************
-// Simple Functions
-//****************************
+ The LZ4 compression library provides in-memory compression and decompression functions.
+ Compression can be done in:
+ - a single step (described as Simple Functions)
+ - a single step, reusing a context (described in Advanced Functions)
+ - unbounded multiple steps (described as Streaming compression)
-int LZ4_compress (const char* source, char* dest, int inputSize);
-int LZ4_decompress_safe (const char* source, char* dest, int inputSize, int maxOutputSize);
+ lz4.h provides block compression functions. It gives full buffer control to user.
+ Decompressing an lz4-compressed block also requires metadata (such as compressed size).
+ Each application is free to encode such metadata in whichever way it wants.
+ An additional format, called LZ4 frame specification (doc/lz4_Frame_format.md),
+ take care of encoding standard metadata alongside LZ4-compressed blocks.
+ If your application requires interoperability, it's recommended to use it.
+ A library is provided to take care of it, see lz4frame.h.
+*/
+
+/*^***************************************************************
+* Export parameters
+*****************************************************************/
/*
-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 ~1.9GB
- return : the number of bytes written in buffer dest
- or 0 if the 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)
- If the source stream is malformed or too large, the function will stop decoding and return a negative result.
- This function is protected against any kind of buffer overflow attemps (never writes outside of output buffer, and never reads outside of input buffer). It is therefore protected against malicious data packets
+* LZ4_DLL_EXPORT :
+* Enable exporting of functions when building a Windows DLL
+* LZ4LIB_API :
+* Control library symbols visibility.
*/
+#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
+# define LZ4LIB_API __declspec(dllexport)
+#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
+# define LZ4LIB_API __declspec(dllimport) /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
+#elif defined(__GNUC__) && (__GNUC__ >= 4)
+# define LZ4LIB_API __attribute__ ((__visibility__ ("default")))
+#else
+# define LZ4LIB_API
+#endif
-//****************************
-// Advanced Functions
-//****************************
+/*------ Version ------*/
+#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
+#define LZ4_VERSION_MINOR 8 /* for new (non-breaking) interface capabilities */
+#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */
-static inline int LZ4_compressBound(int isize) { return ((isize) + ((isize)/255) + 16); }
-#define LZ4_COMPRESSBOUND( isize) ((isize) + ((isize)/255) + 16)
+#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
-/*
-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 compile time (such as table size allocation).
-
- isize : is the input size. Max supported value is ~1.9GB
- return : maximum output size in a "worst case" scenario
- note : this function is limited by "int" range (2^31-1)
+#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE
+#define LZ4_QUOTE(str) #str
+#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
+#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)
+
+LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; to be used when checking dll version */
+LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; to be used when checking dll version */
+
+
+/*-************************************
+* 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
+ */
+#ifndef LZ4_MEMORY_USAGE
+# define LZ4_MEMORY_USAGE 14
+#endif
+
+/*-************************************
+* Simple Functions
+**************************************/
+/*! 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 */
+LZ4LIB_API int LZ4_compress_default(const char* source, char* dest, int sourceSize, int maxDestSize);
+
+/*! LZ4_decompress_safe() :
+ 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, including malicious data packets.
+ It never writes outside output buffer, nor reads outside input buffer.
*/
+LZ4LIB_API int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxDecompressedSize);
-int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
+/*-************************************
+* 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_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 ~1.9GB
- 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_compressBound() :
+ Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
+ This function is primarily useful for memory allocation purposes (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)
*/
+LZ4LIB_API 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.
+*/
+LZ4LIB_API int LZ4_compress_fast (const char* source, char* dest, int sourceSize, int maxDestSize, int acceleration);
-int LZ4_decompress_fast (const char* source, char* dest, int outputSize);
+/*!
+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.
+*/
+LZ4LIB_API int LZ4_sizeofState(void);
+LZ4LIB_API 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
+*/
+LZ4LIB_API int LZ4_compress_destSize (const char* source, char* dest, int* sourceSizePtr, int targetDestSize);
-/*
+
+/*!
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, and never read before input buffer, but may read beyond input buffer (since it doesn't know its size) 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).
*/
+LZ4LIB_API int LZ4_decompress_fast (const char* source, char* dest, int originalSize);
-int LZ4_decompress_safe_partial (const char* source, char* dest, int inputSize, int targetOutputSize, int maxOutputSize);
-
-/*
+/*!
LZ4_decompress_safe_partial() :
- This function decompress a compressed block of size 'inputSize' at position 'source'
- into output buffer 'dest' of size 'maxOutputSize'.
- The function stops decompressing operation as soon as 'targetOutputSize' has been reached,
+ 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)
- Note : this number might be < 'targetOutputSize' if the number of bytes to decode into the compressed block is not enough.
- Always control how many bytes were decoded.
- If the source stream is malformed, the function will stop decoding and return a negative result.
+ 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_withPrefix64k (const char* source, char* dest, int inputSize, int maxOutputSize);
-int LZ4_decompress_fast_withPrefix64k (const char* source, char* dest, int outputSize);
-
-/*
-*_withPrefix64k() :
- These decoding functions work the same as their "normal name" versions,
- but will potentially use up to 64KB of data in front of 'char* dest'.
- These functions are used for decoding inter-dependant blocks.
+LZ4LIB_API int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize);
+
+
+/*-*********************************************
+* Streaming Compression Functions
+***********************************************/
+typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
+
+/*! LZ4_createStream() and LZ4_freeStream() :
+ * LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
+ * LZ4_freeStream() releases its memory.
+ */
+LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
+LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr);
+
+/*! LZ4_resetStream() :
+ * An LZ4_stream_t structure can be allocated once and re-used multiple times.
+ * Use this function to start compressing a new stream.
+ */
+LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
+
+/*! LZ4_loadDict() :
+ * Use this function to load a static dictionary into LZ4_stream_t.
+ * Any previous data will be forgotten, only 'dictionary' will remain in memory.
+ * Loading a size of 0 is allowed, and is the same as reset.
+ * @return : dictionary size, in bytes (necessarily <= 64 KB)
+ */
+LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
+
+/*! LZ4_compress_fast_continue() :
+ * Compress content into 'src' using data from previously compressed blocks, improving compression ratio.
+ * 'dst' buffer must be already allocated.
+ * If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
+ *
+ * Important : Up to 64KB of previously compressed data is assumed to remain present and unmodified in memory !
+ * Special 1 : If input buffer is a double-buffer, it can have any size, including < 64 KB.
+ * Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
+ *
+ * @return : size of compressed block
+ * or 0 if there is an error (typically, compressed data cannot fit into 'dst')
+ * After an error, the stream status is invalid, it can only be reset or freed.
+ */
+LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
+
+/*! LZ4_saveDict() :
+ * If previously compressed data block is not guaranteed to remain available at its current memory location,
+ * save it into a safer place (char* safeBuffer).
+ * Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable.
+ * @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error.
+ */
+LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize);
+
+
+/*-**********************************************
+* Streaming Decompression Functions
+* Bufferless synchronous API
+************************************************/
+typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* incomplete type (defined later) */
+
+/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
+ * creation / destruction of streaming decompression tracking structure.
+ * A tracking structure can be re-used multiple times sequentially. */
+LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
+LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
+
+/*! LZ4_setStreamDecode() :
+ * An LZ4_streamDecode_t structure can be allocated once and re-used multiple times.
+ * Use this function to start decompression of a new stream of blocks.
+ * A dictionary can optionnally be set. Use NULL or size 0 for a simple reset order.
+ * @return : 1 if OK, 0 if error
+ */
+LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
+
+/*! LZ4_decompress_*_continue() :
+ * These decoding functions allow decompression of consecutive blocks in "streaming" mode.
+ * A block is an unsplittable entity, it must be presented entirely to a decompression function.
+ * Decompression functions only accept one block at a time.
+ * Previously decoded blocks *must* remain available at the memory position where they were decoded (up to 64 KB).
+ *
+ * Special : if application sets a ring buffer for decompression, it must respect one of the following conditions :
+ * - 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 of any 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() before decompressing next block.
*/
+LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxDecompressedSize);
+LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize);
+
+
+/*! LZ4_decompress_*_usingDict() :
+ * These decoding functions work the same as
+ * a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
+ * They are stand-alone, and don't need an LZ4_streamDecode_t structure.
+ */
+LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxDecompressedSize, const char* dictStart, int dictSize);
+LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize);
+
+
+/*^**********************************************
+ * !!!!!! STATIC LINKING ONLY !!!!!!
+ ***********************************************/
+/*-************************************
+ * Private definitions
+ **************************************
+ * Do not use these definitions.
+ * They are exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
+ * Using these definitions will expose code to API and/or ABI break in future versions of the library.
+ **************************************/
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
+#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */
+
+#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#include <stdint.h>
+
+typedef struct {
+ uint32_t hashTable[LZ4_HASH_SIZE_U32];
+ uint32_t currentOffset;
+ uint32_t initCheck;
+ const uint8_t* dictionary;
+ uint8_t* bufferStart; /* obsolete, used for slideInputBuffer */
+ uint32_t dictSize;
+} LZ4_stream_t_internal;
+
+typedef struct {
+ const uint8_t* externalDict;
+ size_t extDictSize;
+ const uint8_t* prefixEnd;
+ size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+
+#else
+
+typedef struct {
+ unsigned int hashTable[LZ4_HASH_SIZE_U32];
+ unsigned int currentOffset;
+ unsigned int initCheck;
+ const unsigned char* dictionary;
+ unsigned char* bufferStart; /* obsolete, used for slideInputBuffer */
+ unsigned int dictSize;
+} LZ4_stream_t_internal;
+
+typedef struct {
+ const unsigned char* externalDict;
+ size_t extDictSize;
+ const unsigned char* prefixEnd;
+ size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+#endif
-//****************************
-// 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.
-*/
-
+/*!
+ * LZ4_stream_t :
+ * information structure to track an LZ4 stream.
+ * init this structure before first use.
+ * note : only use in association with static linking !
+ * this definition is not API/ABI safe,
+ * it may change in a future version !
+ */
+#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4)
+#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long))
+union LZ4_stream_u {
+ unsigned long long table[LZ4_STREAMSIZE_U64];
+ LZ4_stream_t_internal internal_donotuse;
+} ; /* previously typedef'd to LZ4_stream_t */
+
+
+/*!
+ * LZ4_streamDecode_t :
+ * information structure to track an LZ4 stream during decompression.
+ * init this structure using LZ4_setStreamDecode (or memset()) before first use
+ * note : only use in association with static linking !
+ * this definition is not API/ABI safe,
+ * and may change in a future version !
+ */
+#define LZ4_STREAMDECODESIZE_U64 4
+#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long))
+union LZ4_streamDecode_u {
+ unsigned long long table[LZ4_STREAMDECODESIZE_U64];
+ LZ4_streamDecode_t_internal internal_donotuse;
+} ; /* previously typedef'd to LZ4_streamDecode_t */
+
+
+/*-************************************
+* Obsolete Functions
+**************************************/
+
+/*! Deprecation warnings
+ Should deprecation warnings be a problem,
+ it is generally possible to disable them,
+ typically with -Wno-deprecated-declarations for gcc
+ or _CRT_SECURE_NO_WARNINGS in Visual.
+ Otherwise, it's also possible to define LZ4_DISABLE_DEPRECATE_WARNINGS */
+#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
+# define LZ4_DEPRECATED(message) /* disable deprecation warnings */
+#else
+# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+# if defined(__clang__) /* clang doesn't handle mixed C++11 and CNU attributes */
+# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
+# elif defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
+# define LZ4_DEPRECATED(message) [[deprecated(message)]]
+# elif (LZ4_GCC_VERSION >= 405)
+# 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_DISABLE_DEPRECATE_WARNINGS */
+
+/* Obsolete compression functions */
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress (const char* source, char* dest, int sourceSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
+
+/* Obsolete decompression functions */
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast() instead") int LZ4_uncompress (const char* source, char* dest, int outputSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe() instead") int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
+
+/* Obsolete streaming functions; use new streaming interface whenever possible */
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") void* LZ4_create (char* inputBuffer);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") int LZ4_sizeofStreamState(void);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_resetStream() instead") int LZ4_resetStreamState(void* state, char* inputBuffer);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_saveDict() instead") char* LZ4_slideInputBuffer (void* state);
+
+/* Obsolete streaming decoding functions */
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
+LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
+
+#endif /* LZ4_H_2983827168210 */
#if defined (__cplusplus)
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