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-rw-r--r--ext/lz4/lz4.c2071
1 files changed, 1249 insertions, 822 deletions
diff --git a/ext/lz4/lz4.c b/ext/lz4/lz4.c
index 5668521f..d58be27a 100644
--- a/ext/lz4/lz4.c
+++ b/ext/lz4/lz4.c
@@ -1,822 +1,1249 @@
-/*
- LZ4 - Fast LZ compression algorithm
- Copyright (C) 2011-2013, Yann Collet.
- BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are
- met:
-
- * Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above
- copyright notice, this list of conditions and the following disclaimer
- in the documentation and/or other materials provided with the
- distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
- You can contact the author at :
- - LZ4 source repository : http://code.google.com/p/lz4/
- - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
-*/
-
-//**************************************
-// Tuning parameters
-//**************************************
-// MEMORY_USAGE :
-// Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
-// Increasing memory usage improves compression ratio
-// Reduced memory usage can improve speed, due to cache effect
-// Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
-#define MEMORY_USAGE 14
-
-// HEAPMODE :
-// Select how default compression functions will allocate memory for their hash table,
-// in memory stack (0:default, fastest), or in memory heap (1:requires memory allocation (malloc)).
-#define HEAPMODE 0
-
-
-//**************************************
-// CPU Feature Detection
-//**************************************
-// 32 or 64 bits ?
-#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \
- || defined(__powerpc64__) || defined(__ppc64__) || defined(__PPC64__) \
- || defined(__64BIT__) || defined(_LP64) || defined(__LP64__) \
- || defined(__ia64) || defined(__itanium__) || defined(_M_IA64) ) // Detects 64 bits mode
-# define LZ4_ARCH64 1
-#else
-# define LZ4_ARCH64 0
-#endif
-
-// Little Endian or Big Endian ?
-// Overwrite the #define below if you know your architecture endianess
-#if defined (__GLIBC__)
-# include <endian.h>
-# if (__BYTE_ORDER == __BIG_ENDIAN)
-# define LZ4_BIG_ENDIAN 1
-# endif
-#elif (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(__LITTLE_ENDIAN__) || defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN))
-# define LZ4_BIG_ENDIAN 1
-#elif defined(__sparc) || defined(__sparc__) \
- || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \
- || defined(__hpux) || defined(__hppa) \
- || defined(_MIPSEB) || defined(__s390__)
-# define LZ4_BIG_ENDIAN 1
-#else
-// Little Endian assumed. PDP Endian and other very rare endian format are unsupported.
-#endif
-
-// Unaligned memory access is automatically enabled for "common" CPU, such as x86.
-// For others CPU, such as ARM, the compiler may be more cautious, inserting unnecessary extra code to ensure aligned access property
-// If you know your target CPU supports unaligned memory access, you want to force this option manually to improve performance
-#if defined(__ARM_FEATURE_UNALIGNED)
-# define LZ4_FORCE_UNALIGNED_ACCESS 1
-#endif
-
-// Define this parameter if your target system or compiler does not support hardware bit count
-#if defined(_MSC_VER) && defined(_WIN32_WCE) // Visual Studio for Windows CE does not support Hardware bit count
-# define LZ4_FORCE_SW_BITCOUNT
-#endif
-
-// BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :
-// This option may provide a small boost to performance for some big endian cpu, although probably modest.
-// You may set this option to 1 if data will remain within closed environment.
-// This option is useless on Little_Endian CPU (such as x86)
-//#define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1
-
-
-//**************************************
-// Compiler Options
-//**************************************
-#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) // C99
-/* "restrict" is a known keyword */
-#else
-# define restrict // Disable restrict
-#endif
-
-#ifdef _MSC_VER // Visual Studio
-# define FORCE_INLINE static __forceinline
-# include <intrin.h> // For Visual 2005
-# if LZ4_ARCH64 // 64-bits
-# pragma intrinsic(_BitScanForward64) // For Visual 2005
-# pragma intrinsic(_BitScanReverse64) // For Visual 2005
-# else // 32-bits
-# pragma intrinsic(_BitScanForward) // For Visual 2005
-# pragma intrinsic(_BitScanReverse) // For Visual 2005
-# endif
-# pragma warning(disable : 4127) // disable: C4127: conditional expression is constant
-#else
-# ifdef __GNUC__
-# define FORCE_INLINE static inline __attribute__((always_inline))
-# else
-# define FORCE_INLINE static inline
-# endif
-#endif
-
-#ifdef _MSC_VER
-# define lz4_bswap16(x) _byteswap_ushort(x)
-#else
-# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
-#endif
-
-#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-
-#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
-# define expect(expr,value) (__builtin_expect ((expr),(value)) )
-#else
-# define expect(expr,value) (expr)
-#endif
-
-#define likely(expr) expect((expr) != 0, 1)
-#define unlikely(expr) expect((expr) != 0, 0)
-
-
-//**************************************
-// Memory routines
-//**************************************
-#include <stdlib.h> // malloc, calloc, free
-#define ALLOCATOR(n,s) calloc(n,s)
-#define FREEMEM free
-#include <string.h> // memset, memcpy
-#define MEM_INIT memset
-
-
-//**************************************
-// Includes
-//**************************************
-#include "lz4.h"
-
-
-//**************************************
-// Basic Types
-//**************************************
-#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L // C99
-# include <stdint.h>
- typedef uint8_t BYTE;
- typedef uint16_t U16;
- typedef uint32_t U32;
- typedef int32_t S32;
- typedef uint64_t U64;
-#else
- typedef unsigned char BYTE;
- typedef unsigned short U16;
- typedef unsigned int U32;
- typedef signed int S32;
- typedef unsigned long long U64;
-#endif
-
-#if defined(__GNUC__) && !defined(LZ4_FORCE_UNALIGNED_ACCESS)
-# define _PACKED __attribute__ ((packed))
-#else
-# define _PACKED
-#endif
-
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
-# if defined(__IBMC__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
-# pragma pack(1)
-# else
-# pragma pack(push, 1)
-# endif
-#endif
-
-typedef struct { U16 v; } _PACKED U16_S;
-typedef struct { U32 v; } _PACKED U32_S;
-typedef struct { U64 v; } _PACKED U64_S;
-typedef struct {size_t v;} _PACKED size_t_S;
-
-#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
-# if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
-# pragma pack(0)
-# else
-# pragma pack(pop)
-# endif
-#endif
-
-#define A16(x) (((U16_S *)(x))->v)
-#define A32(x) (((U32_S *)(x))->v)
-#define A64(x) (((U64_S *)(x))->v)
-#define AARCH(x) (((size_t_S *)(x))->v)
-
-
-//**************************************
-// Constants
-//**************************************
-#define LZ4_HASHLOG (MEMORY_USAGE-2)
-#define HASHTABLESIZE (1 << MEMORY_USAGE)
-#define HASHNBCELLS4 (1 << LZ4_HASHLOG)
-
-#define MINMATCH 4
-
-#define COPYLENGTH 8
-#define LASTLITERALS 5
-#define MFLIMIT (COPYLENGTH+MINMATCH)
-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 MAXD_LOG 16
-#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
-
-#define ML_BITS 4
-#define ML_MASK ((1U<<ML_BITS)-1)
-#define RUN_BITS (8-ML_BITS)
-#define RUN_MASK ((1U<<RUN_BITS)-1)
-
-#define KB *(1U<<10)
-#define MB *(1U<<20)
-#define GB *(1U<<30)
-
-
-//**************************************
-// Structures and local types
-//**************************************
-
-typedef struct {
- U32 hashTable[HASHNBCELLS4];
- const BYTE* bufferStart;
- const BYTE* base;
- const BYTE* nextBlock;
-} LZ4_Data_Structure;
-
-typedef enum { notLimited = 0, limited = 1 } limitedOutput_directive;
-typedef enum { byPtr, byU32, byU16 } tableType_t;
-
-typedef enum { noPrefix = 0, withPrefix = 1 } prefix64k_directive;
-
-typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
-typedef enum { full = 0, partial = 1 } earlyEnd_directive;
-
-
-//**************************************
-// Architecture-specific macros
-//**************************************
-#define STEPSIZE sizeof(size_t)
-#define LZ4_COPYSTEP(d,s) { AARCH(d) = AARCH(s); d+=STEPSIZE; s+=STEPSIZE; }
-#define LZ4_COPY8(d,s) { LZ4_COPYSTEP(d,s); if (STEPSIZE<8) LZ4_COPYSTEP(d,s); }
-#define LZ4_SECURECOPY(d,s,e) { if ((STEPSIZE==4)||(d<e)) LZ4_WILDCOPY(d,s,e); }
-
-#if LZ4_ARCH64 // 64-bit
-# define HTYPE U32
-# define INITBASE(base) const BYTE* const base = ip
-#else // 32-bit
-# define HTYPE const BYTE*
-# define INITBASE(base) const int base = 0
-#endif
-
-#if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE))
-# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
-# define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }
-#else // Little Endian
-# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }
-# define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; }
-#endif
-
-
-//**************************************
-// Macros
-//**************************************
-#define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); } // at the end, d>=e;
-
-
-//****************************
-// Private functions
-//****************************
-#if LZ4_ARCH64
-
-FORCE_INLINE int LZ4_NbCommonBytes (register U64 val)
-{
-# if defined(LZ4_BIG_ENDIAN)
-# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse64( &r, val );
- return (int)(r>>3);
-# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clzll(val) >> 3);
-# else
- int r;
- if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
- if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
- r += (!val);
- return r;
-# endif
-# else
-# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanForward64( &r, val );
- return (int)(r>>3);
-# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctzll(val) >> 3);
-# else
- static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
- return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
-# endif
-# endif
-}
-
-#else
-
-FORCE_INLINE int LZ4_NbCommonBytes (register U32 val)
-{
-# if defined(LZ4_BIG_ENDIAN)
-# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r = 0;
- _BitScanReverse( &r, val );
- return (int)(r>>3);
-# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_clz(val) >> 3);
-# else
- int r;
- if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
- r += (!val);
- return r;
-# endif
-# else
-# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
- unsigned long r;
- _BitScanForward( &r, val );
- return (int)(r>>3);
-# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
- return (__builtin_ctz(val) >> 3);
-# else
- static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
- return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
-# endif
-# endif
-}
-
-#endif
-
-
-//****************************
-// Compression functions
-//****************************
-FORCE_INLINE int LZ4_hashSequence(U32 sequence, tableType_t tableType)
-{
- if (tableType == byU16)
- return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
- else
- return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
-}
-
-FORCE_INLINE int LZ4_hashPosition(const BYTE* p, tableType_t tableType) { return LZ4_hashSequence(A32(p), tableType); }
-
-FORCE_INLINE void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
-{
- switch (tableType)
- {
- case byPtr: { const BYTE** hashTable = (const BYTE**) tableBase; hashTable[h] = p; break; }
- case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); break; }
- case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); break; }
- }
-}
-
-FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
-{
- U32 h = LZ4_hashPosition(p, tableType);
- LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
-}
-
-FORCE_INLINE const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
-{
- if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; }
- if (tableType == byU32) { U32* hashTable = (U32*) tableBase; return hashTable[h] + srcBase; }
- { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } // default, to ensure a return
-}
-
-FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
-{
- U32 h = LZ4_hashPosition(p, tableType);
- return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
-}
-
-
-FORCE_INLINE int LZ4_compress_generic(
- void* ctx,
- const char* source,
- char* dest,
- int inputSize,
- int maxOutputSize,
-
- limitedOutput_directive limitedOutput,
- tableType_t tableType,
- prefix64k_directive prefix)
-{
- const BYTE* ip = (const BYTE*) source;
- const BYTE* const base = (prefix==withPrefix) ? ((LZ4_Data_Structure*)ctx)->base : (const BYTE*) source;
- const BYTE* const lowLimit = ((prefix==withPrefix) ? ((LZ4_Data_Structure*)ctx)->bufferStart : (const BYTE*)source);
- const BYTE* anchor = (const BYTE*) source;
- const BYTE* const iend = ip + inputSize;
- const BYTE* const mflimit = iend - MFLIMIT;
- const BYTE* const matchlimit = iend - LASTLITERALS;
-
- BYTE* op = (BYTE*) dest;
- BYTE* const oend = op + maxOutputSize;
-
- int length;
- const int skipStrength = SKIPSTRENGTH;
- U32 forwardH;
-
- // Init conditions
- if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; // Unsupported input size, too large (or negative)
- if ((prefix==withPrefix) && (ip != ((LZ4_Data_Structure*)ctx)->nextBlock)) return 0; // must continue from end of previous block
- if (prefix==withPrefix) ((LZ4_Data_Structure*)ctx)->nextBlock=iend; // do it now, due to potential early exit
- if ((tableType == byU16) && (inputSize>=LZ4_64KLIMIT)) return 0; // Size too large (not within 64K limit)
- if (inputSize<LZ4_minLength) goto _last_literals; // Input too small, no compression (all literals)
-
- // First Byte
- LZ4_putPosition(ip, ctx, tableType, base);
- ip++; forwardH = LZ4_hashPosition(ip, tableType);
-
- // Main Loop
- for ( ; ; )
- {
- int findMatchAttempts = (1U << skipStrength) + 3;
- const BYTE* forwardIp = ip;
- const BYTE* ref;
- BYTE* token;
-
- // Find a match
- do {
- U32 h = forwardH;
- int step = findMatchAttempts++ >> skipStrength;
- ip = forwardIp;
- forwardIp = ip + step;
-
- if unlikely(forwardIp > mflimit) { goto _last_literals; }
-
- forwardH = LZ4_hashPosition(forwardIp, tableType);
- ref = LZ4_getPositionOnHash(h, ctx, tableType, base);
- LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
-
- } while ((ref + MAX_DISTANCE < ip) || (A32(ref) != A32(ip)));
-
- // Catch up
- while ((ip>anchor) && (ref > lowLimit) && unlikely(ip[-1]==ref[-1])) { ip--; ref--; }
-
- // Encode Literal length
- length = (int)(ip - anchor);
- token = op++;
- if ((limitedOutput) && unlikely(op + length + (2 + 1 + LASTLITERALS) + (length>>8) > oend)) return 0; // Check output limit
- if (length>=(int)RUN_MASK)
- {
- int len = length-RUN_MASK;
- *token=(RUN_MASK<<ML_BITS);
- for(; len >= 255 ; len-=255) *op++ = 255;
- *op++ = (BYTE)len;
- }
- else *token = (BYTE)(length<<ML_BITS);
-
- // Copy Literals
- { BYTE* end=(op)+(length); LZ4_WILDCOPY(op,anchor,end); op=end; }
-
-_next_match:
- // Encode Offset
- LZ4_WRITE_LITTLEENDIAN_16(op,(U16)(ip-ref));
-
- // Start Counting
- ip+=MINMATCH; ref+=MINMATCH; // MinMatch already verified
- anchor = ip;
- while likely(ip<matchlimit-(STEPSIZE-1))
- {
- size_t diff = AARCH(ref) ^ AARCH(ip);
- if (!diff) { ip+=STEPSIZE; ref+=STEPSIZE; continue; }
- ip += LZ4_NbCommonBytes(diff);
- goto _endCount;
- }
- if (LZ4_ARCH64) if ((ip<(matchlimit-3)) && (A32(ref) == A32(ip))) { ip+=4; ref+=4; }
- if ((ip<(matchlimit-1)) && (A16(ref) == A16(ip))) { ip+=2; ref+=2; }
- if ((ip<matchlimit) && (*ref == *ip)) ip++;
-_endCount:
-
- // Encode MatchLength
- length = (int)(ip - anchor);
- if ((limitedOutput) && unlikely(op + (1 + LASTLITERALS) + (length>>8) > oend)) return 0; // Check output limit
- if (length>=(int)ML_MASK)
- {
- *token += ML_MASK;
- length -= ML_MASK;
- for (; length > 509 ; length-=510) { *op++ = 255; *op++ = 255; }
- if (length >= 255) { length-=255; *op++ = 255; }
- *op++ = (BYTE)length;
- }
- else *token += (BYTE)(length);
-
- // Test end of chunk
- if (ip > mflimit) { anchor = ip; break; }
-
- // Fill table
- LZ4_putPosition(ip-2, ctx, tableType, base);
-
- // Test next position
- ref = LZ4_getPosition(ip, ctx, tableType, base);
- LZ4_putPosition(ip, ctx, tableType, base);
- if ((ref + MAX_DISTANCE >= ip) && (A32(ref) == A32(ip))) { token = op++; *token=0; goto _next_match; }
-
- // Prepare next loop
- anchor = ip++;
- forwardH = LZ4_hashPosition(ip, tableType);
- }
-
-_last_literals:
- // Encode Last Literals
- {
- int lastRun = (int)(iend - anchor);
- if ((limitedOutput) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) return 0; // Check output limit
- if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun >= 255 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
- else *op++ = (BYTE)(lastRun<<ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend-anchor;
- }
-
- // End
- return (int) (((char*)op)-dest);
-}
-
-
-int LZ4_compress(const char* source, char* dest, int inputSize)
-{
-#if (HEAPMODE)
- void* ctx = ALLOCATOR(HASHNBCELLS4, 4); // Aligned on 4-bytes boundaries
-#else
- U32 ctx[1U<<(MEMORY_USAGE-2)] = {0}; // Ensure data is aligned on 4-bytes boundaries
-#endif
- int result;
-
- if (inputSize < (int)LZ4_64KLIMIT)
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, byU16, noPrefix);
- else
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noPrefix);
-
-#if (HEAPMODE)
- FREEMEM(ctx);
-#endif
- return result;
-}
-
-int LZ4_compress_continue (void* LZ4_Data, const char* source, char* dest, int inputSize)
-{
- return LZ4_compress_generic(LZ4_Data, source, dest, inputSize, 0, notLimited, byU32, withPrefix);
-}
-
-
-int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
-{
-#if (HEAPMODE)
- void* ctx = ALLOCATOR(HASHNBCELLS4, 4); // Aligned on 4-bytes boundaries
-#else
- U32 ctx[1U<<(MEMORY_USAGE-2)] = {0}; // Ensure data is aligned on 4-bytes boundaries
-#endif
- int result;
-
- if (inputSize < (int)LZ4_64KLIMIT)
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limited, byU16, noPrefix);
- else
- result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limited, (sizeof(void*)==8) ? byU32 : byPtr, noPrefix);
-
-#if (HEAPMODE)
- FREEMEM(ctx);
-#endif
- return result;
-}
-
-int LZ4_compress_limitedOutput_continue (void* LZ4_Data, const char* source, char* dest, int inputSize, int maxOutputSize)
-{
- return LZ4_compress_generic(LZ4_Data, source, dest, inputSize, maxOutputSize, limited, byU32, withPrefix);
-}
-
-
-//****************************
-// Stream functions
-//****************************
-
-FORCE_INLINE void LZ4_init(LZ4_Data_Structure* lz4ds, const BYTE* base)
-{
- MEM_INIT(lz4ds->hashTable, 0, sizeof(lz4ds->hashTable));
- lz4ds->bufferStart = base;
- lz4ds->base = base;
- lz4ds->nextBlock = base;
-}
-
-
-void* LZ4_create (const char* inputBuffer)
-{
- void* lz4ds = ALLOCATOR(1, sizeof(LZ4_Data_Structure));
- LZ4_init ((LZ4_Data_Structure*)lz4ds, (const BYTE*)inputBuffer);
- return lz4ds;
-}
-
-
-int LZ4_free (void* LZ4_Data)
-{
- FREEMEM(LZ4_Data);
- return (0);
-}
-
-
-char* LZ4_slideInputBuffer (void* LZ4_Data)
-{
- LZ4_Data_Structure* lz4ds = (LZ4_Data_Structure*)LZ4_Data;
- size_t delta = lz4ds->nextBlock - (lz4ds->bufferStart + 64 KB);
-
- if ( (lz4ds->base - delta > lz4ds->base) // underflow control
- || ((size_t)(lz4ds->nextBlock - lz4ds->base) > 0xE0000000) ) // close to 32-bits limit
- {
- size_t deltaLimit = (lz4ds->nextBlock - 64 KB) - lz4ds->base;
- int nH;
-
- for (nH=0; nH < HASHNBCELLS4; nH++)
- {
- if ((size_t)(lz4ds->hashTable[nH]) < deltaLimit) lz4ds->hashTable[nH] = 0;
- else lz4ds->hashTable[nH] -= (U32)deltaLimit;
- }
- memcpy((void*)(lz4ds->bufferStart), (const void*)(lz4ds->nextBlock - 64 KB), 64 KB);
- lz4ds->base = lz4ds->bufferStart;
- lz4ds->nextBlock = lz4ds->base + 64 KB;
- }
- else
- {
- memcpy((void*)(lz4ds->bufferStart), (const void*)(lz4ds->nextBlock - 64 KB), 64 KB);
- lz4ds->nextBlock -= delta;
- lz4ds->base -= delta;
- }
-
- return (char*)(lz4ds->nextBlock);
-}
-
-
-//****************************
-// Decompression functions
-//****************************
-
-// This generic decompression function cover all use cases.
-// It shall be instanciated several times, using different sets of directives
-// Note that it is essential this generic function is really inlined,
-// in order to remove useless branches during compilation optimisation.
-FORCE_INLINE int LZ4_decompress_generic(
- const char* source,
- char* dest,
- int inputSize, //
- int outputSize, // If endOnInput==endOnInputSize, this value is the max size of Output Buffer.
-
- int endOnInput, // endOnOutputSize, endOnInputSize
- int prefix64k, // noPrefix, withPrefix
- int partialDecoding, // full, partial
- int targetOutputSize // only used if partialDecoding==partial
- )
-{
- // Local Variables
- const BYTE* restrict ip = (const BYTE*) source;
- const BYTE* ref;
- const BYTE* const iend = ip + inputSize;
-
- BYTE* op = (BYTE*) dest;
- BYTE* const oend = op + outputSize;
- BYTE* cpy;
- BYTE* oexit = op + targetOutputSize;
-
- const size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; // static reduces speed for LZ4_decompress_safe() on GCC64
- static const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
-
-
- // Special cases
- if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; // targetOutputSize too high => decode everything
- if ((endOnInput) && unlikely(outputSize==0)) return ((inputSize==1) && (*ip==0)) ? 0 : -1; // Empty output buffer
- if ((!endOnInput) && unlikely(outputSize==0)) return (*ip==0?1:-1);
-
-
- // Main Loop
- while (1)
- {
- unsigned token;
- size_t length;
-
- // get runlength
- token = *ip++;
- if ((length=(token>>ML_BITS)) == RUN_MASK)
- {
- unsigned s=255;
- while (((endOnInput)?ip<iend:1) && (s==255))
- {
- s = *ip++;
- length += s;
- }
- }
-
- // copy literals
- cpy = op+length;
- if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) )
- || ((!endOnInput) && (cpy>oend-COPYLENGTH)))
- {
- if (partialDecoding)
- {
- if (cpy > oend) goto _output_error; // Error : write attempt beyond end of output buffer
- if ((endOnInput) && (ip+length > iend)) goto _output_error; // Error : read attempt beyond end of input buffer
- }
- else
- {
- if ((!endOnInput) && (cpy != oend)) goto _output_error; // Error : block decoding must stop exactly there
- if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; // Error : input must be consumed
- }
- memcpy(op, ip, length);
- ip += length;
- op += length;
- break; // Necessarily EOF, due to parsing restrictions
- }
- LZ4_WILDCOPY(op, ip, cpy); ip -= (op-cpy); op = cpy;
-
- // get offset
- LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;
- if ((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))) // Ensure enough bytes remain for LASTLITERALS + token
- {
- unsigned s = *ip++;
- length += s;
- if (s==255) continue;
- break;
- }
- }
-
- // copy repeated sequence
- if unlikely((op-ref)<(int)STEPSIZE)
- {
- const size_t dec64 = dec64table[(sizeof(void*)==4) ? 0 : op-ref];
- op[0] = ref[0];
- op[1] = ref[1];
- op[2] = ref[2];
- op[3] = ref[3];
- op += 4, ref += 4; ref -= dec32table[op-ref];
- A32(op) = A32(ref);
- op += STEPSIZE-4; ref -= dec64;
- } else { LZ4_COPYSTEP(op,ref); }
- cpy = op + length - (STEPSIZE-4);
-
- if unlikely(cpy>oend-COPYLENGTH-(STEPSIZE-4))
- {
- if (cpy > oend-LASTLITERALS) goto _output_error; // Error : last 5 bytes must be literals
- LZ4_SECURECOPY(op, ref, (oend-COPYLENGTH));
- while(op<cpy) *op++=*ref++;
- op=cpy;
- continue;
- }
- LZ4_WILDCOPY(op, ref, cpy);
- op=cpy; // correction
- }
-
- // end of decoding
- if (endOnInput)
- return (int) (((char*)op)-dest); // Nb of output bytes decoded
- else
- return (int) (((char*)ip)-source); // Nb of input bytes read
-
- // Overflow error detected
-_output_error:
- return (int) (-(((char*)ip)-source))-1;
-}
-
-
-int LZ4_decompress_safe(const char* source, char* dest, int inputSize, int maxOutputSize)
-{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, noPrefix, full, 0);
-}
-
-int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int inputSize, int maxOutputSize)
-{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, withPrefix, full, 0);
-}
-
-int LZ4_decompress_safe_partial(const char* source, char* dest, int inputSize, int targetOutputSize, int maxOutputSize)
-{
- return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, noPrefix, partial, targetOutputSize);
-}
-
-int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int outputSize)
-{
- return LZ4_decompress_generic(source, dest, 0, outputSize, endOnOutputSize, withPrefix, full, 0);
-}
-
-int LZ4_decompress_fast(const char* source, char* dest, int outputSize)
-{
-#ifdef _MSC_VER // This version is faster with Visual
- return LZ4_decompress_generic(source, dest, 0, outputSize, endOnOutputSize, noPrefix, full, 0);
-#else
- return LZ4_decompress_generic(source, dest, 0, outputSize, endOnOutputSize, withPrefix, full, 0);
-#endif
-}
-
+/*
+ LZ4 - Fast LZ compression algorithm
+ Copyright (C) 2011-2014, Yann Collet.
+ BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are
+ met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+ copyright notice, this list of conditions and the following disclaimer
+ in the documentation and/or other materials provided with the
+ distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ You can contact the author at :
+ - LZ4 source repository : http://code.google.com/p/lz4/
+ - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
+*/
+
+/**************************************
+ Tuning parameters
+**************************************/
+/*
+ * HEAPMODE :
+ * Select how default compression functions will allocate memory for their hash table,
+ * in memory stack (0:default, fastest), or in memory heap (1:requires memory allocation (malloc)).
+ */
+#define HEAPMODE 0
+
+
+/**************************************
+ CPU Feature Detection
+**************************************/
+/* 32 or 64 bits ? */
+#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \
+ || defined(__powerpc64__) || defined(__powerpc64le__) \
+ || defined(__ppc64__) || defined(__ppc64le__) \
+ || defined(__PPC64__) || defined(__PPC64LE__) \
+ || defined(__ia64) || defined(__itanium__) || defined(_M_IA64) ) /* Detects 64 bits mode */
+# define LZ4_ARCH64 1
+#else
+# define LZ4_ARCH64 0
+#endif
+#define LZ4_32BITS (sizeof(void*)==4)
+#define LZ4_64BITS (sizeof(void*)==8)
+
+/*
+ * Little Endian or Big Endian ?
+ * Overwrite the #define below if you know your architecture endianess
+ */
+#include <stdlib.h> /* Apparently required to detect endianess */
+#if defined (__GLIBC__)
+# include <endian.h>
+# if (__BYTE_ORDER == __BIG_ENDIAN)
+# define LZ4_BIG_ENDIAN 1
+# endif
+#elif (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(__LITTLE_ENDIAN__) || defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN))
+# define LZ4_BIG_ENDIAN 1
+#elif defined(__sparc) || defined(__sparc__) \
+ || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \
+ || defined(__hpux) || defined(__hppa) \
+ || defined(_MIPSEB) || defined(__s390__)
+# define LZ4_BIG_ENDIAN 1
+#else
+/* Little Endian assumed. PDP Endian and other very rare endian format are unsupported. */
+#endif
+
+/*
+ * Unaligned memory access is automatically enabled for "common" CPU, such as x86.
+ * For others CPU, such as ARM, the compiler may be more cautious, inserting unnecessary extra code to ensure aligned access property
+ * If you know your target CPU supports unaligned memory access, you want to force this option manually to improve performance
+ */
+#if defined(__ARM_FEATURE_UNALIGNED)
+# define LZ4_FORCE_UNALIGNED_ACCESS 1
+#endif
+
+/* Define this parameter if your target system or compiler does not support hardware bit count */
+#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE does not support Hardware bit count */
+# define LZ4_FORCE_SW_BITCOUNT
+#endif
+
+/*
+ * BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :
+ * This option may provide a small boost to performance for some big endian cpu, although probably modest.
+ * You may set this option to 1 if data will remain within closed environment.
+ * This option is useless on Little_Endian CPU (such as x86)
+ */
+
+/* #define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1 */
+
+
+/**************************************
+ Compiler Options
+**************************************/
+#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
+/* "restrict" is a known keyword */
+#else
+# define restrict /* Disable restrict */
+#endif
+
+#ifdef _MSC_VER /* Visual Studio */
+# define FORCE_INLINE static __forceinline
+# include <intrin.h> /* For Visual 2005 */
+# if LZ4_ARCH64 /* 64-bits */
+# pragma intrinsic(_BitScanForward64) /* For Visual 2005 */
+# pragma intrinsic(_BitScanReverse64) /* For Visual 2005 */
+# else /* 32-bits */
+# pragma intrinsic(_BitScanForward) /* For Visual 2005 */
+# pragma intrinsic(_BitScanReverse) /* For Visual 2005 */
+# endif
+# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
+#else
+# ifdef __GNUC__
+# define FORCE_INLINE static inline __attribute__((always_inline))
+# else
+# define FORCE_INLINE static inline
+# endif
+#endif
+
+#ifdef _MSC_VER /* Visual Studio */
+# define lz4_bswap16(x) _byteswap_ushort(x)
+#else
+# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
+#endif
+
+#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+
+#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
+# define expect(expr,value) (__builtin_expect ((expr),(value)) )
+#else
+# define expect(expr,value) (expr)
+#endif
+
+#define likely(expr) expect((expr) != 0, 1)
+#define unlikely(expr) expect((expr) != 0, 0)
+
+
+/**************************************
+ Memory routines
+**************************************/
+#include <stdlib.h> /* malloc, calloc, free */
+#define ALLOCATOR(n,s) calloc(n,s)
+#define FREEMEM free
+#include <string.h> /* memset, memcpy */
+#define MEM_INIT memset
+
+
+/**************************************
+ Includes
+**************************************/
+#include "lz4.h"
+
+
+/**************************************
+ Basic Types
+**************************************/
+#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */
+# include <stdint.h>
+ typedef uint8_t BYTE;
+ typedef uint16_t U16;
+ typedef uint32_t U32;
+ typedef int32_t S32;
+ typedef uint64_t U64;
+#else
+ typedef unsigned char BYTE;
+ typedef unsigned short U16;
+ typedef unsigned int U32;
+ typedef signed int S32;
+ typedef unsigned long long U64;
+#endif
+
+#if defined(__GNUC__) && !defined(LZ4_FORCE_UNALIGNED_ACCESS)
+# define _PACKED __attribute__ ((packed))
+#else
+# define _PACKED
+#endif
+
+#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
+# if defined(__IBMC__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
+# pragma pack(1)
+# else
+# pragma pack(push, 1)
+# endif
+#endif
+
+typedef struct { U16 v; } _PACKED U16_S;
+typedef struct { U32 v; } _PACKED U32_S;
+typedef struct { U64 v; } _PACKED U64_S;
+typedef struct {size_t v;} _PACKED size_t_S;
+
+#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__)
+# if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
+# pragma pack(0)
+# else
+# pragma pack(pop)
+# endif
+#endif
+
+#define A16(x) (((U16_S *)(x))->v)
+#define A32(x) (((U32_S *)(x))->v)
+#define A64(x) (((U64_S *)(x))->v)
+#define AARCH(x) (((size_t_S *)(x))->v)
+
+
+/**************************************
+ Constants
+**************************************/
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
+#define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define HASH_SIZE_U32 (1 << LZ4_HASHLOG)
+
+#define MINMATCH 4
+
+#define COPYLENGTH 8
+#define LASTLITERALS 5
+#define MFLIMIT (COPYLENGTH+MINMATCH)
+static const int LZ4_minLength = (MFLIMIT+1);
+
+#define KB *(1U<<10)
+#define MB *(1U<<20)
+#define GB *(1U<<30)
+
+#define LZ4_64KLIMIT ((64 KB) + (MFLIMIT-1))
+#define SKIPSTRENGTH 6 /* Increasing this value will make the compression run slower on incompressible data */
+
+#define MAXD_LOG 16
+#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
+
+#define ML_BITS 4
+#define ML_MASK ((1U<<ML_BITS)-1)
+#define RUN_BITS (8-ML_BITS)
+#define RUN_MASK ((1U<<RUN_BITS)-1)
+
+
+/**************************************
+ Structures and local types
+**************************************/
+typedef struct {
+ U32 hashTable[HASH_SIZE_U32];
+ U32 currentOffset;
+ U32 initCheck;
+ const BYTE* dictionary;
+ const BYTE* bufferStart;
+ U32 dictSize;
+} LZ4_stream_t_internal;
+
+typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { byPtr, byU32, byU16 } tableType_t;
+
+typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
+
+typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
+typedef enum { full = 0, partial = 1 } earlyEnd_directive;
+
+
+/**************************************
+ Architecture-specific macros
+**************************************/
+#define STEPSIZE sizeof(size_t)
+#define LZ4_COPYSTEP(d,s) { AARCH(d) = AARCH(s); d+=STEPSIZE; s+=STEPSIZE; }
+#define LZ4_COPY8(d,s) { LZ4_COPYSTEP(d,s); if (STEPSIZE<8) LZ4_COPYSTEP(d,s); }
+
+#if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE))
+# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
+# define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }
+#else /* Little Endian */
+# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }
+# define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; }
+#endif
+
+
+/**************************************
+ Macros
+**************************************/
+#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(!!(c)) }; } /* use only *after* variable declarations */
+#if LZ4_ARCH64 || !defined(__GNUC__)
+# define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); } /* at the end, d>=e; */
+#else
+# define LZ4_WILDCOPY(d,s,e) { if (likely(e-d <= 8)) LZ4_COPY8(d,s) else do { LZ4_COPY8(d,s) } while (d<e); }
+#endif
+
+
+/****************************
+ Private local functions
+****************************/
+#if LZ4_ARCH64
+
+static int LZ4_NbCommonBytes (register U64 val)
+{
+# if defined(LZ4_BIG_ENDIAN)
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanReverse64( &r, val );
+ return (int)(r>>3);
+# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_clzll(val) >> 3);
+# else
+ int r;
+ if (!(val>>32)) { r=4; } else { r=0; val>>=32; }
+ if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
+ r += (!val);
+ return r;
+# endif
+# else
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanForward64( &r, val );
+ return (int)(r>>3);
+# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_ctzll(val) >> 3);
+# else
+ static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
+ return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
+# endif
+# endif
+}
+
+#else
+
+static int LZ4_NbCommonBytes (register U32 val)
+{
+# if defined(LZ4_BIG_ENDIAN)
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r = 0;
+ _BitScanReverse( &r, val );
+ return (int)(r>>3);
+# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_clz(val) >> 3);
+# else
+ int r;
+ if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
+ r += (!val);
+ return r;
+# endif
+# else
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ unsigned long r;
+ _BitScanForward( &r, val );
+ return (int)(r>>3);
+# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)
+ return (__builtin_ctz(val) >> 3);
+# else
+ static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
+ return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
+# endif
+# endif
+}
+
+#endif
+
+
+/********************************
+ Compression functions
+********************************/
+int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; }
+int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
+
+static int LZ4_hashSequence(U32 sequence, tableType_t tableType)
+{
+ if (tableType == byU16)
+ return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
+ else
+ return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
+}
+
+static int LZ4_hashPosition(const BYTE* p, tableType_t tableType) { return LZ4_hashSequence(A32(p), tableType); }
+
+static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ switch (tableType)
+ {
+ case byPtr: { const BYTE** hashTable = (const BYTE**) tableBase; hashTable[h] = p; break; }
+ case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); break; }
+ case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); break; }
+ }
+}
+
+static void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ U32 h = LZ4_hashPosition(p, tableType);
+ LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+}
+
+static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; }
+ if (tableType == byU32) { U32* hashTable = (U32*) tableBase; return hashTable[h] + srcBase; }
+ { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
+}
+
+static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+{
+ U32 h = LZ4_hashPosition(p, tableType);
+ return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
+}
+
+static unsigned LZ4_count(const BYTE* pIn, const BYTE* pRef, const BYTE* pInLimit)
+{
+ const BYTE* const pStart = pIn;
+
+ while (likely(pIn<pInLimit-(STEPSIZE-1)))
+ {
+ size_t diff = AARCH(pRef) ^ AARCH(pIn);
+ if (!diff) { pIn+=STEPSIZE; pRef+=STEPSIZE; continue; }
+ pIn += LZ4_NbCommonBytes(diff);
+ return (unsigned)(pIn - pStart);
+ }
+ if (LZ4_64BITS) if ((pIn<(pInLimit-3)) && (A32(pRef) == A32(pIn))) { pIn+=4; pRef+=4; }
+ if ((pIn<(pInLimit-1)) && (A16(pRef) == A16(pIn))) { pIn+=2; pRef+=2; }
+ if ((pIn<pInLimit) && (*pRef == *pIn)) pIn++;
+
+ return (unsigned)(pIn - pStart);
+}
+
+
+static int LZ4_compress_generic(
+ void* ctx,
+ const char* source,
+ char* dest,
+ int inputSize,
+ int maxOutputSize,
+
+ limitedOutput_directive outputLimited,
+ tableType_t tableType,
+ dict_directive dict,
+ dictIssue_directive dictIssue)
+{
+ LZ4_stream_t_internal* const dictPtr = (LZ4_stream_t_internal*)ctx;
+
+ const BYTE* ip = (const BYTE*) source;
+ const BYTE* base;
+ const BYTE* lowLimit;
+ const BYTE* const lowRefLimit = ip - dictPtr->dictSize;
+ const BYTE* const dictionary = dictPtr->dictionary;
+ const BYTE* const dictEnd = dictionary + dictPtr->dictSize;
+ const size_t dictDelta = dictEnd - (const BYTE*)source;
+ const BYTE* anchor = (const BYTE*) source;
+ const BYTE* const iend = ip + inputSize;
+ const BYTE* const mflimit = iend - MFLIMIT;
+ const BYTE* const matchlimit = iend - LASTLITERALS;
+
+ BYTE* op = (BYTE*) dest;
+ BYTE* const olimit = op + maxOutputSize;
+
+ const int skipStrength = SKIPSTRENGTH;
+ U32 forwardH;
+ size_t refDelta=0;
+
+ /* Init conditions */
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */
+ switch(dict)
+ {
+ case noDict:
+ default:
+ base = (const BYTE*)source;
+ lowLimit = (const BYTE*)source;
+ break;
+ case withPrefix64k:
+ base = (const BYTE*)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE*)source - dictPtr->dictSize;
+ break;
+ case usingExtDict:
+ base = (const BYTE*)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE*)source;
+ break;
+ }
+ if ((tableType == byU16) && (inputSize>=(int)LZ4_64KLIMIT)) return 0; /* Size too large (not within 64K limit) */
+ if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
+
+ /* First Byte */
+ LZ4_putPosition(ip, ctx, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; )
+ {
+ const BYTE* ref;
+ BYTE* token;
+ {
+ const BYTE* forwardIp = ip;
+ unsigned step=1;
+ unsigned searchMatchNb = (1U << skipStrength);
+
+ /* Find a match */
+ do {
+ U32 h = forwardH;
+ ip = forwardIp;
+ forwardIp += step;
+ step = searchMatchNb++ >> skipStrength;
+
+ if (unlikely(forwardIp > mflimit)) goto _last_literals;
+
+ ref = LZ4_getPositionOnHash(h, ctx, tableType, base);
+ if (dict==usingExtDict)
+ {
+ if (ref<(const BYTE*)source)
+ {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ }
+ else
+ {
+ refDelta = 0;
+ lowLimit = (const BYTE*)source;
+ }
+ }
+ forwardH = LZ4_hashPosition(forwardIp, tableType);
+ LZ4_putPositionOnHash(ip, h, ctx, tableType, base);
+
+ } while ( ((dictIssue==dictSmall) ? (ref < lowRefLimit) : 0)
+ || ((tableType==byU16) ? 0 : (ref + MAX_DISTANCE < ip))
+ || (A32(ref+refDelta) != A32(ip)) );
+ }
+
+ /* Catch up */
+ while ((ip>anchor) && (ref+refDelta > lowLimit) && (unlikely(ip[-1]==ref[refDelta-1]))) { ip--; ref--; }
+
+ {
+ /* Encode Literal length */
+ unsigned litLength = (unsigned)(ip - anchor);
+ token = op++;
+ if ((outputLimited) && (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)))
+ return 0; /* Check output limit */
+ if (litLength>=RUN_MASK)
+ {
+ int len = (int)litLength-RUN_MASK;
+ *token=(RUN_MASK<<ML_BITS);
+ for(; len >= 255 ; len-=255) *op++ = 255;
+ *op++ = (BYTE)len;
+ }
+ else *token = (BYTE)(litLength<<ML_BITS);
+
+ /* Copy Literals */
+ { BYTE* end = op+litLength; LZ4_WILDCOPY(op,anchor,end); op=end; }
+ }
+
+_next_match:
+ /* Encode Offset */
+ LZ4_WRITE_LITTLEENDIAN_16(op, (U16)(ip-ref));
+
+ /* Encode MatchLength */
+ {
+ unsigned matchLength;
+
+ if ((dict==usingExtDict) && (lowLimit==dictionary))
+ {
+ const BYTE* limit;
+ ref += refDelta;
+ limit = ip + (dictEnd-ref);
+ if (limit > matchlimit) limit = matchlimit;
+ matchLength = LZ4_count(ip+MINMATCH, ref+MINMATCH, limit);
+ ip += MINMATCH + matchLength;
+ if (ip==limit)
+ {
+ unsigned more = LZ4_count(ip, (const BYTE*)source, matchlimit);
+ matchLength += more;
+ ip += more;
+ }
+ }
+ else
+ {
+ matchLength = LZ4_count(ip+MINMATCH, ref+MINMATCH, matchlimit);
+ ip += MINMATCH + matchLength;
+ }
+
+ if (matchLength>=ML_MASK)
+ {
+ if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) + (matchLength>>8) > olimit)))
+ return 0; /* Check output limit */
+ *token += ML_MASK;
+ matchLength -= ML_MASK;
+ for (; matchLength >= 510 ; matchLength-=510) { *op++ = 255; *op++ = 255; }
+ if (matchLength >= 255) { matchLength-=255; *op++ = 255; }
+ *op++ = (BYTE)matchLength;
+ }
+ else *token += (BYTE)(matchLength);
+ }
+
+ anchor = ip;
+
+ /* Test end of chunk */
+ if (ip > mflimit) break;
+
+ /* Fill table */
+ LZ4_putPosition(ip-2, ctx, tableType, base);
+
+ /* Test next position */
+ ref = LZ4_getPosition(ip, ctx, tableType, base);
+ if (dict==usingExtDict)
+ {
+ if (ref<(const BYTE*)source)
+ {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ }
+ else
+ {
+ refDelta = 0;
+ lowLimit = (const BYTE*)source;
+ }
+ }
+ LZ4_putPosition(ip, ctx, tableType, base);
+ if ( ((dictIssue==dictSmall) ? (ref>=lowRefLimit) : 1)
+ && (ref+MAX_DISTANCE>=ip)
+ && (A32(ref+refDelta)==A32(ip)) )
+ { token=op++; *token=0; goto _next_match; }
+
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
+ }
+
+_last_literals:
+ /* Encode Last Literals */
+ {
+ int lastRun = (int)(iend - anchor);
+ if ((outputLimited) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize))
+ return 0; /* Check output limit */
+ if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun >= 255 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
+ else *op++ = (BYTE)(lastRun<<ML_BITS);
+ memcpy(op, anchor, iend - anchor);
+ op += iend-anchor;
+ }
+
+ /* End */
+ return (int) (((char*)op)-dest);
+}
+
+
+int LZ4_compress(const char* source, char* dest, int inputSize)
+{
+#if (HEAPMODE)
+ void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */
+#else
+ U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */
+#endif
+ int result;
+
+ if (inputSize < (int)LZ4_64KLIMIT)
+ result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue);
+ else
+ result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, LZ4_64BITS ? byU32 : byPtr, noDict, noDictIssue);
+
+#if (HEAPMODE)
+ FREEMEM(ctx);
+#endif
+ return result;
+}
+
+int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize)
+{
+#if (HEAPMODE)
+ void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */
+#else
+ U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */
+#endif
+ int result;
+
+ if (inputSize < (int)LZ4_64KLIMIT)
+ result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue);
+ else
+ result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64BITS ? byU32 : byPtr, noDict, noDictIssue);
+
+#if (HEAPMODE)
+ FREEMEM(ctx);
+#endif
+ return result;
+}
+
+
+/*****************************************
+ Experimental : Streaming functions
+*****************************************/
+
+/*
+ * LZ4_initStream
+ * Use this function once, to init a newly allocated LZ4_stream_t structure
+ * Return : 1 if OK, 0 if error
+ */
+void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
+{
+ MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
+
+LZ4_stream_t* LZ4_createStream(void)
+{
+ LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(4, LZ4_STREAMSIZE_U32);
+ LZ4_resetStream(lz4s);
+ return lz4s;
+}
+
+int LZ4_freeStream (LZ4_stream_t* LZ4_stream)
+{
+ FREEMEM(LZ4_stream);
+ return (0);
+}
+
+
+int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
+{
+ LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
+ const BYTE* p = (const BYTE*)dictionary;
+ const BYTE* const dictEnd = p + dictSize;
+ const BYTE* base;
+
+ LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
+ if (dict->initCheck) LZ4_resetStream(LZ4_dict); /* Uninitialized structure detected */
+
+ if (dictSize < MINMATCH)
+ {
+ dict->dictionary = NULL;
+ dict->dictSize = 0;
+ return 1;
+ }
+
+ if (p <= dictEnd - 64 KB) p = dictEnd - 64 KB;
+ base = p - dict->currentOffset;
+ dict->dictionary = p;
+ dict->dictSize = (U32)(dictEnd - p);
+ dict->currentOffset += dict->dictSize;
+
+ while (p <= dictEnd-MINMATCH)
+ {
+ LZ4_putPosition(p, dict, byU32, base);
+ p+=3;
+ }
+
+ return 1;
+}
+
+
+static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src)
+{
+ if ((LZ4_dict->currentOffset > 0x80000000) ||
+ ((size_t)LZ4_dict->currentOffset > (size_t)src)) /* address space overflow */
+ {
+ /* rescale hash table */
+ U32 delta = LZ4_dict->currentOffset - 64 KB;
+ const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
+ int i;
+ for (i=0; i<HASH_SIZE_U32; i++)
+ {
+ if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0;
+ else LZ4_dict->hashTable[i] -= delta;
+ }
+ LZ4_dict->currentOffset = 64 KB;
+ if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB;
+ LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
+ }
+}
+
+
+FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* source, char* dest, int inputSize,
+ int maxOutputSize, limitedOutput_directive limit)
+{
+ LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_stream;
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+
+ const BYTE* smallest = (const BYTE*) source;
+ if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */
+ if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd;
+ LZ4_renormDictT(streamPtr, smallest);
+
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE* sourceEnd = (const BYTE*) source + inputSize;
+ if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd))
+ {
+ streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
+ if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB;
+ if (streamPtr->dictSize < 4) streamPtr->dictSize = 0;
+ streamPtr->dictionary = dictEnd - streamPtr->dictSize;
+ }
+ }
+
+ /* prefix mode : source data follows dictionary */
+ if (dictEnd == (const BYTE*)source)
+ {
+ int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, withPrefix64k, dictSmall);
+ else
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, withPrefix64k, noDictIssue);
+ streamPtr->dictSize += (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+
+ /* external dictionary mode */
+ {
+ int result;
+ if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, usingExtDict, dictSmall);
+ else
+ result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, usingExtDict, noDictIssue);
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+}
+
+int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize)
+{
+ return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, 0, notLimited);
+}
+
+int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize)
+{
+ return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput);
+}
+
+
+/* Hidden debug function, to force separate dictionary mode */
+int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize)
+{
+ LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_dict;
+ int result;
+ const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+
+ const BYTE* smallest = dictEnd;
+ if (smallest > (const BYTE*) source) smallest = (const BYTE*) source;
+ LZ4_renormDictT((LZ4_stream_t_internal*)LZ4_dict, smallest);
+
+ result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue);
+
+ streamPtr->dictionary = (const BYTE*)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+
+ return result;
+}
+
+
+int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize)
+{
+ LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
+ const BYTE* previousDictEnd = dict->dictionary + dict->dictSize;
+
+ if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a dictionary > 64 KB */
+ if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize;
+
+ memcpy(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+ dict->dictionary = (const BYTE*)safeBuffer;
+ dict->dictSize = (U32)dictSize;
+
+ return 1;
+}
+
+
+
+/****************************
+ Decompression functions
+****************************/
+/*
+ * This generic decompression function cover all use cases.
+ * It shall be instanciated several times, using different sets of directives
+ * Note that it is essential this generic function is really inlined,
+ * in order to remove useless branches during compilation optimisation.
+ */
+FORCE_INLINE int LZ4_decompress_generic(
+ const char* source,
+ char* dest,
+ int inputSize,
+ int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */
+
+ int endOnInput, /* endOnOutputSize, endOnInputSize */
+ int partialDecoding, /* full, partial */
+ int targetOutputSize, /* only used if partialDecoding==partial */
+ int dict, /* noDict, withPrefix64k, usingExtDict */
+ const char* dictStart, /* only if dict==usingExtDict */
+ int dictSize /* note : = 0 if noDict */
+ )
+{
+ /* Local Variables */
+ const BYTE* restrict ip = (const BYTE*) source;
+ const BYTE* ref;
+ const BYTE* const iend = ip + inputSize;
+
+ BYTE* op = (BYTE*) dest;
+ BYTE* const oend = op + outputSize;
+ BYTE* cpy;
+ BYTE* oexit = op + targetOutputSize;
+ const BYTE* const lowLimit = (const BYTE*)dest - dictSize;
+
+ const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize;
+ const size_t dec32table[] = {4-0, 4-3, 4-2, 4-3, 4-0, 4-0, 4-0, 4-0}; /* note : static reduces speed for LZ4_decompress_safe() on GCC64 */
+ static const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3};
+
+ const int safeDecode = (endOnInput==endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
+
+
+ /* Special cases */
+ if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */
+ if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
+ if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1);
+
+
+ /* Main Loop */
+ while (1)
+ {
+ unsigned token;
+ size_t length;
+
+ /* get runlength */
+ token = *ip++;
+ if ((length=(token>>ML_BITS)) == RUN_MASK)
+ {
+ unsigned s;
+ do
+ {
+ s = *ip++;
+ length += s;
+ }
+ while (likely((endOnInput)?ip<iend-RUN_MASK:1) && (s==255));
+ if ((safeDecode) && LZ4_32BITS && unlikely((size_t)(op+length)<(size_t)(op))) goto _output_error; /* overflow detection */
+ if ((safeDecode) && LZ4_32BITS && unlikely((size_t)(ip+length)<(size_t)(ip))) goto _output_error; /* overflow detection */
+ }
+
+ /* copy literals */
+ cpy = op+length;
+ if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) )
+ || ((!endOnInput) && (cpy>oend-COPYLENGTH)))
+ {
+ if (partialDecoding)
+ {
+ if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */
+ if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */
+ }
+ else
+ {
+ if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */
+ if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */
+ }
+ memcpy(op, ip, length);
+ ip += length;
+ op += length;
+ break; /* Necessarily EOF, due to parsing restrictions */
+ }
+ LZ4_WILDCOPY(op, ip, cpy); ip -= (op-cpy); op = cpy;
+
+ /* get offset */
+ LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;
+ if ((checkOffset) && (unlikely(ref < lowLimit))) goto _output_error; /* Error : offset outside destination buffer */
+
+ /* get matchlength */
+ if ((length=(token&ML_MASK)) == ML_MASK)
+ {
+ unsigned s;
+ do
+ {
+ if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error;
+ s = *ip++;
+ length += s;
+ } while (s==255);
+ if ((safeDecode) && LZ4_32BITS && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* overflow detection */
+ }
+
+ /* check external dictionary */
+ if ((dict==usingExtDict) && (ref < (BYTE* const)dest))
+ {
+ if (unlikely(op+length+MINMATCH > oend-LASTLITERALS)) goto _output_error;
+
+ if (length+MINMATCH <= (size_t)(dest-(char*)ref))
+ {
+ ref = dictEnd - (dest-(char*)ref);
+ memcpy(op, ref, length+MINMATCH);
+ op += length+MINMATCH;
+ }
+ else
+ {
+ size_t copySize = (size_t)(dest-(char*)ref);
+ memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+ copySize = length+MINMATCH - copySize;
+ if (copySize > (size_t)((char*)op-dest)) /* overlap */
+ {
+ BYTE* const endOfMatch = op + copySize;
+ const BYTE* copyFrom = (BYTE*)dest;
+ while (op < endOfMatch) *op++ = *copyFrom++;
+ }
+ else
+ {
+ memcpy(op, dest, copySize);
+ op += copySize;
+ }
+ }
+ continue;
+ }
+
+ /* copy repeated sequence */
+ if (unlikely((op-ref)<(int)STEPSIZE))
+ {
+ const size_t dec64 = dec64table[LZ4_32BITS ? 0 : op-ref];
+ op[0] = ref[0];
+ op[1] = ref[1];
+ op[2] = ref[2];
+ op[3] = ref[3];
+ ref += dec32table[op-ref];
+ A32(op+4) = A32(ref);
+ op += STEPSIZE; ref -= dec64;
+ } else { LZ4_COPYSTEP(op,ref); }
+ cpy = op + length - (STEPSIZE-4);
+
+ if (unlikely(cpy>oend-COPYLENGTH-(STEPSIZE-4)))
+ {
+ if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last 5 bytes must be literals */
+ if (op<oend-COPYLENGTH) LZ4_WILDCOPY(op, ref, (oend-COPYLENGTH));
+ while(op<cpy) *op++=*ref++;
+ op=cpy;
+ continue;
+ }
+ LZ4_WILDCOPY(op, ref, cpy);
+ op=cpy; /* correction */
+ }
+
+ /* end of decoding */
+ if (endOnInput)
+ return (int) (((char*)op)-dest); /* Nb of output bytes decoded */
+ else
+ return (int) (((char*)ip)-source); /* Nb of input bytes read */
+
+ /* Overflow error detected */
+_output_error:
+ return (int) (-(((char*)ip)-source))-1;
+}
+
+
+int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, full, 0, noDict, 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, NULL, 0);
+}
+
+int LZ4_decompress_fast(const char* source, char* dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, NULL, 64 KB);
+}
+
+/* streaming decompression functions */
+
+typedef struct
+{
+ const char* dictionary;
+ int dictSize;
+} LZ4_streamDecode_t_internal;
+
+/*
+ * If you prefer dynamic allocation methods,
+ * LZ4_createStreamDecode()
+ * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure.
+ */
+LZ4_streamDecode_t* LZ4_createStreamDecode(void)
+{
+ LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(sizeof(U32), LZ4_STREAMDECODESIZE_U32);
+ MEM_INIT(lz4s, 0, LZ4_STREAMDECODESIZE);
+ return lz4s;
+}
+
+int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream)
+{
+ FREEMEM(LZ4_stream);
+ return 0;
+}
+
+/*
+ * LZ4_setStreamDecode
+ * Use this function to instruct where to find the dictionary
+ * This function is not necessary if previous data is still available where it was decoded.
+ * Loading a size of 0 is allowed (same effect as no dictionary).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
+ lz4sd->dictionary = dictionary;
+ lz4sd->dictSize = dictSize;
+ return 1;
+}
+
+/*
+*_continue() :
+ These decoding functions allow decompression of multiple blocks in "streaming" mode.
+ Previously decoded blocks must still be available at the memory position where they were decoded.
+ If it's not possible, save the relevant part of decoded data into a safe buffer,
+ and indicate where it stands using LZ4_setDictDecode()
+*/
+int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
+ int result;
+
+ result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize);
+ if (result <= 0) return result;
+ if (lz4sd->dictionary + lz4sd->dictSize == dest)
+ {
+ lz4sd->dictSize += result;
+ }
+ else
+ {
+ lz4sd->dictionary = dest;
+ lz4sd->dictSize = result;
+ }
+
+ return result;
+}
+
+int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize)
+{
+ LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode;
+ int result;
+
+ result = LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize);
+ if (result <= 0) return result;
+ if (lz4sd->dictionary + lz4sd->dictSize == dest)
+ {
+ lz4sd->dictSize += result;
+ }
+ else
+ {
+ lz4sd->dictionary = dest;
+ lz4sd->dictSize = result;
+ }
+
+ return result;
+}
+
+
+/*
+Advanced decoding functions :
+*_usingDict() :
+ These decoding functions work the same as "_continue" ones,
+ the dictionary must be explicitly provided within parameters
+*/
+
+int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, dictStart, dictSize);
+}
+
+int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, dictStart, dictSize);
+}
+
+
+/***************************************************
+ Obsolete Functions
+***************************************************/
+/*
+These function names are deprecated and should no longer be used.
+They are only provided here for compatibility with older user programs.
+- LZ4_uncompress is totally equivalent to LZ4_decompress_fast
+- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
+*/
+int LZ4_uncompress (const char* source, char* dest, int outputSize) { return LZ4_decompress_fast(source, dest, outputSize); }
+int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize, maxOutputSize); }
+
+
+/* Obsolete Streaming functions */
+
+int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; }
+
+static void LZ4_init(LZ4_stream_t_internal* lz4ds, const BYTE* base)
+{
+ MEM_INIT(lz4ds, 0, LZ4_STREAMSIZE);
+ lz4ds->bufferStart = base;
+}
+
+int LZ4_resetStreamState(void* state, const char* inputBuffer)
+{
+ if ((((size_t)state) & 3) != 0) return 1; /* Error : pointer is not aligned on 4-bytes boundary */
+ LZ4_init((LZ4_stream_t_internal*)state, (const BYTE*)inputBuffer);
+ return 0;
+}
+
+void* LZ4_create (const char* inputBuffer)
+{
+ void* lz4ds = ALLOCATOR(4, LZ4_STREAMSIZE_U32);
+ LZ4_init ((LZ4_stream_t_internal*)lz4ds, (const BYTE*)inputBuffer);
+ return lz4ds;
+}
+
+char* LZ4_slideInputBuffer (void* LZ4_Data)
+{
+ LZ4_stream_t_internal* lz4ds = (LZ4_stream_t_internal*)LZ4_Data;
+
+ LZ4_saveDict((LZ4_stream_t*)LZ4_Data, (char*)lz4ds->bufferStart, 64 KB);
+
+ return (char*)(lz4ds->bufferStart + 64 KB);
+}
+
+/* Obsolete compresson functions using User-allocated state */
+
+int LZ4_sizeofState() { return LZ4_STREAMSIZE; }
+
+int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize)
+{
+ if (((size_t)(state)&3) != 0) return 0; /* Error : state is not aligned on 4-bytes boundary */
+ MEM_INIT(state, 0, LZ4_STREAMSIZE);
+
+ if (inputSize < (int)LZ4_64KLIMIT)
+ return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue);
+ else
+ return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, LZ4_64BITS ? byU32 : byPtr, noDict, noDictIssue);
+}
+
+int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize)
+{
+ if (((size_t)(state)&3) != 0) return 0; /* Error : state is not aligned on 4-bytes boundary */
+ MEM_INIT(state, 0, LZ4_STREAMSIZE);
+
+ if (inputSize < (int)LZ4_64KLIMIT)
+ return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue);
+ else
+ return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64BITS ? byU32 : byPtr, noDict, noDictIssue);
+}
+
+/* Obsolete streaming decompression functions */
+
+int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, withPrefix64k, NULL, 64 KB);
+}
+
+int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, NULL, 64 KB);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-28 08:32:41 +0000