-/*\r
- LZ4 - Fast LZ compression algorithm\r
- Copyright (C) 2011-2012, Yann Collet.\r
- BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)\r
-\r
- Redistribution and use in source and binary forms, with or without\r
- modification, are permitted provided that the following conditions are\r
- met:\r
-\r
- * Redistributions of source code must retain the above copyright\r
- notice, this list of conditions and the following disclaimer.\r
- * Redistributions in binary form must reproduce the above\r
- copyright notice, this list of conditions and the following disclaimer\r
- in the documentation and/or other materials provided with the\r
- distribution.\r
-\r
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\r
- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\r
- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\r
- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\r
- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\r
- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\r
- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\r
- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\r
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\r
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\r
- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r
-\r
- You can contact the author at :\r
- - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html\r
- - LZ4 source repository : http://code.google.com/p/lz4/\r
-*/\r
-\r
-//**************************************\r
-// Tuning parameters\r
-//**************************************\r
-// COMPRESSIONLEVEL :\r
-// Increasing this value improves compression ratio\r
-// Lowering this value reduces memory usage\r
-// Reduced memory usage typically improves speed, due to cache effect (ex : L1 32KB for Intel, L1 64KB for AMD)\r
-// Memory usage formula : N->2^(N+2) Bytes (examples : 12 -> 16KB ; 17 -> 512KB)\r
-#define COMPRESSIONLEVEL 12\r
-\r
-// NOTCOMPRESSIBLE_CONFIRMATION :\r
-// Decreasing this value will make the algorithm skip faster data segments considered "incompressible"\r
-// This may decrease compression ratio dramatically, but will be faster on incompressible data\r
-// Increasing this value will make the algorithm search more before declaring a segment "incompressible"\r
-// This could improve compression a bit, but will be slower on incompressible data\r
-// The default value (6) is recommended\r
-#define NOTCOMPRESSIBLE_CONFIRMATION 6\r
-\r
-// LZ4_COMPRESSMIN :\r
-// Compression function will *fail* if it is not successful at compressing input by at least LZ4_COMPRESSMIN bytes\r
-// Since the compression function stops working prematurely, it results in a speed gain\r
-// The output however is unusable. Compression function result will be zero.\r
-// Default : 0 = disabled\r
-#define LZ4_COMPRESSMIN 0\r
-\r
-// BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :\r
-// This will provide a boost to performance for big endian cpu, but the resulting compressed stream will be incompatible with little-endian CPU.\r
-// You can set this option to 1 in situations where data will stay within closed environment\r
-// This option is useless on Little_Endian CPU (such as x86)\r
-//#define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1\r
-\r
-\r
-\r
-//**************************************\r
-// CPU Feature Detection\r
-//**************************************\r
-// 32 or 64 bits ?\r
-#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) || defined(__amd64) || defined(__ppc64__) || defined(_WIN64) || defined(__LP64__) || defined(_LP64) ) // Detects 64 bits mode\r
-# define LZ4_ARCH64 1\r
-#else\r
-# define LZ4_ARCH64 0\r
-#endif\r
-\r
-// Little Endian or Big Endian ?\r
-// Note : overwrite the below #define if you know your architecture endianess\r
-#if (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN) || defined(_ARCH_PPC) || defined(__PPC__) || defined(__PPC) || defined(PPC) || defined(__powerpc__) || defined(__powerpc) || defined(powerpc) || ((defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))) )\r
-# define LZ4_BIG_ENDIAN 1\r
-#else\r
-// Little Endian assumed. PDP Endian and other very rare endian format are unsupported.\r
-#endif\r
-\r
-// Unaligned memory access is automatically enabled for "common" CPU, such as x86.\r
-// For others CPU, the compiler will be more cautious, and insert extra code to ensure aligned access is respected\r
-// If you know your target CPU supports unaligned memory access, you may want to force this option manually to improve performance\r
-#if defined(__ARM_FEATURE_UNALIGNED)\r
-# define LZ4_FORCE_UNALIGNED_ACCESS 1\r
-#endif\r
-\r
-// Define this parameter if your target system or compiler does not support hardware bit count\r
-#if defined(_MSC_VER) && defined(_WIN32_WCE) // Visual Studio for Windows CE does not support Hardware bit count\r
-# define LZ4_FORCE_SW_BITCOUNT\r
-#endif\r
-\r
-\r
-//**************************************\r
-// Compiler Options\r
-//**************************************\r
-#if __STDC_VERSION__ >= 199901L // C99\r
-/* "restrict" is a known keyword */\r
-#else\r
-# define restrict // Disable restrict\r
-#endif\r
-\r
-#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)\r
-\r
-#ifdef _MSC_VER // Visual Studio\r
-# define inline __forceinline // Visual is not C99, but supports some kind of inline\r
-# if LZ4_ARCH64 // 64-bit\r
-# pragma intrinsic(_BitScanForward64) // For Visual 2005\r
-# pragma intrinsic(_BitScanReverse64) // For Visual 2005\r
-# else\r
-# pragma intrinsic(_BitScanForward) // For Visual 2005\r
-# pragma intrinsic(_BitScanReverse) // For Visual 2005\r
-# endif\r
-#endif\r
-\r
-#ifdef _MSC_VER\r
-# define lz4_bswap16(x) _byteswap_ushort(x)\r
-#else\r
-# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))\r
-#endif\r
-\r
-#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)\r
-# define expect(expr,value) (__builtin_expect ((expr),(value)) )\r
-#else\r
-# define expect(expr,value) (expr)\r
-#endif\r
-\r
-#define likely(expr) expect((expr) != 0, 1)\r
-#define unlikely(expr) expect((expr) != 0, 0)\r
-\r
-\r
-//**************************************\r
-// Includes\r
-//**************************************\r
-#include <stdlib.h> // for malloc\r
-#include <string.h> // for memset\r
-#include "lz4.h"\r
-\r
-\r
-//**************************************\r
-// Basic Types\r
-//**************************************\r
-#if defined(_MSC_VER) // Visual Studio does not support 'stdint' natively\r
-# define BYTE unsigned __int8\r
-# define U16 unsigned __int16\r
-# define U32 unsigned __int32\r
-# define S32 __int32\r
-# define U64 unsigned __int64\r
-#else\r
-# include <stdint.h>\r
-# define BYTE uint8_t\r
-# define U16 uint16_t\r
-# define U32 uint32_t\r
-# define S32 int32_t\r
-# define U64 uint64_t\r
-#endif\r
-\r
-#ifndef LZ4_FORCE_UNALIGNED_ACCESS\r
-# pragma pack(push, 1)\r
-#endif\r
-\r
-typedef struct _U16_S { U16 v; } U16_S;\r
-typedef struct _U32_S { U32 v; } U32_S;\r
-typedef struct _U64_S { U64 v; } U64_S;\r
-\r
-#ifndef LZ4_FORCE_UNALIGNED_ACCESS\r
-# pragma pack(pop)\r
-#endif\r
-\r
-#define A64(x) (((U64_S *)(x))->v)\r
-#define A32(x) (((U32_S *)(x))->v)\r
-#define A16(x) (((U16_S *)(x))->v)\r
-\r
-\r
-//**************************************\r
-// Constants\r
-//**************************************\r
-#define MINMATCH 4\r
-\r
-#define HASH_LOG COMPRESSIONLEVEL\r
-#define HASHTABLESIZE (1 << HASH_LOG)\r
-#define HASH_MASK (HASHTABLESIZE - 1)\r
-\r
-#define SKIPSTRENGTH (NOTCOMPRESSIBLE_CONFIRMATION>2?NOTCOMPRESSIBLE_CONFIRMATION:2)\r
-#define STACKLIMIT 13\r
-#define HEAPMODE (HASH_LOG>STACKLIMIT) // Defines if memory is allocated into the stack (local variable), or into the heap (malloc()).\r
-#define COPYLENGTH 8\r
-#define LASTLITERALS 5\r
-#define MFLIMIT (COPYLENGTH+MINMATCH)\r
-#define MINLENGTH (MFLIMIT+1)\r
-\r
-#define MAXD_LOG 16\r
-#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)\r
-\r
-#define ML_BITS 4\r
-#define ML_MASK ((1U<<ML_BITS)-1)\r
-#define RUN_BITS (8-ML_BITS)\r
-#define RUN_MASK ((1U<<RUN_BITS)-1)\r
-\r
-\r
-//**************************************\r
-// Architecture-specific macros\r
-//**************************************\r
-#if LZ4_ARCH64 // 64-bit\r
-# define STEPSIZE 8\r
-# define UARCH U64\r
-# define AARCH A64\r
-# define LZ4_COPYSTEP(s,d) A64(d) = A64(s); d+=8; s+=8;\r
-# define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d)\r
-# define LZ4_SECURECOPY(s,d,e) if (d<e) LZ4_WILDCOPY(s,d,e)\r
-# define HTYPE U32\r
-# define INITBASE(base) const BYTE* const base = ip\r
-#else // 32-bit\r
-# define STEPSIZE 4\r
-# define UARCH U32\r
-# define AARCH A32\r
-# define LZ4_COPYSTEP(s,d) A32(d) = A32(s); d+=4; s+=4;\r
-# define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d); LZ4_COPYSTEP(s,d);\r
-# define LZ4_SECURECOPY LZ4_WILDCOPY\r
-# define HTYPE const BYTE*\r
-# define INITBASE(base) const int base = 0\r
-#endif\r
-\r
-#if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE))\r
-# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }\r
-# define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; }\r
-#else // Little Endian\r
-# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); }\r
-# define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; }\r
-#endif\r
-\r
-\r
-//**************************************\r
-// Local structures\r
-//**************************************\r
-struct refTables\r
-{\r
- HTYPE hashTable[HASHTABLESIZE];\r
-};\r
-\r
-\r
-//**************************************\r
-// Macros\r
-//**************************************\r
-#define LZ4_HASH_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8)-HASH_LOG))\r
-#define LZ4_HASH_VALUE(p) LZ4_HASH_FUNCTION(A32(p))\r
-#define LZ4_WILDCOPY(s,d,e) do { LZ4_COPYPACKET(s,d) } while (d<e);\r
-#define LZ4_BLINDCOPY(s,d,l) { BYTE* e=(d)+l; LZ4_WILDCOPY(s,d,e); d=e; }\r
-\r
-\r
-//****************************\r
-// Private functions\r
-//****************************\r
-#if LZ4_ARCH64\r
-\r
-inline static int LZ4_NbCommonBytes (register U64 val)\r
-{\r
-#if defined(LZ4_BIG_ENDIAN)\r
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- unsigned long r = 0;\r
- _BitScanReverse64( &r, val );\r
- return (int)(r>>3);\r
- #elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- return (__builtin_clzll(val) >> 3);\r
- #else\r
- int r;\r
- if (!(val>>32)) { r=4; } else { r=0; val>>=32; }\r
- if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }\r
- r += (!val);\r
- return r;\r
- #endif\r
-#else\r
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- unsigned long r = 0;\r
- _BitScanForward64( &r, val );\r
- return (int)(r>>3);\r
- #elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- return (__builtin_ctzll(val) >> 3);\r
- #else\r
- 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 };\r
- return DeBruijnBytePos[((U64)((val & -val) * 0x0218A392CDABBD3F)) >> 58];\r
- #endif\r
-#endif\r
-}\r
-\r
-#else\r
-\r
-inline static int LZ4_NbCommonBytes (register U32 val)\r
-{\r
-#if defined(LZ4_BIG_ENDIAN)\r
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- unsigned long r = 0;\r
- _BitScanReverse( &r, val );\r
- return (int)(r>>3);\r
- #elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- return (__builtin_clz(val) >> 3);\r
- #else\r
- int r;\r
- if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }\r
- r += (!val);\r
- return r;\r
- #endif\r
-#else\r
- #if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- unsigned long r = 0;\r
- _BitScanForward( &r, val );\r
- return (int)(r>>3);\r
- #elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT)\r
- return (__builtin_ctz(val) >> 3);\r
- #else\r
- 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 };\r
- return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];\r
- #endif\r
-#endif\r
-}\r
-\r
-#endif\r
-\r
-\r
-//****************************\r
-// Public functions\r
-//****************************\r
-\r
-int LZ4_compressBound(int isize)\r
-{\r
- return (isize + (isize/255) + 16);\r
-}\r
-\r
-\r
-\r
-//******************************\r
-// Compression functions\r
-//******************************\r
-\r
-int LZ4_compressCtx(void** ctx,\r
- const char* source,\r
- char* dest,\r
- int isize)\r
-{\r
-#if HEAPMODE\r
- struct refTables *srt = (struct refTables *) (*ctx);\r
- HTYPE* HashTable;\r
-#else\r
- HTYPE HashTable[HASHTABLESIZE] = {0};\r
-#endif\r
-\r
- const BYTE* ip = (BYTE*) source;\r
- INITBASE(base);\r
- const BYTE* anchor = ip;\r
- const BYTE* const iend = ip + isize;\r
- const BYTE* const mflimit = iend - MFLIMIT;\r
-#define matchlimit (iend - LASTLITERALS)\r
-\r
- BYTE* op = (BYTE*) dest;\r
-\r
- int len, length;\r
- const int skipStrength = SKIPSTRENGTH;\r
- U32 forwardH;\r
-\r
-\r
- // Init\r
- if (isize<MINLENGTH) goto _last_literals;\r
-#if HEAPMODE\r
- if (*ctx == NULL)\r
- {\r
- srt = (struct refTables *) malloc ( sizeof(struct refTables) );\r
- *ctx = (void*) srt;\r
- }\r
- HashTable = (HTYPE*)(srt->hashTable);\r
- memset((void*)HashTable, 0, sizeof(srt->hashTable));\r
-#else\r
- (void) ctx;\r
-#endif\r
-\r
-\r
- // First Byte\r
- HashTable[LZ4_HASH_VALUE(ip)] = ip - base;\r
- ip++; forwardH = LZ4_HASH_VALUE(ip);\r
-\r
- // Main Loop\r
- for ( ; ; )\r
- {\r
- int findMatchAttempts = (1U << skipStrength) + 3;\r
- const BYTE* forwardIp = ip;\r
- const BYTE* ref;\r
- BYTE* token;\r
-\r
- // Find a match\r
- do {\r
- U32 h = forwardH;\r
- int step = findMatchAttempts++ >> skipStrength;\r
- ip = forwardIp;\r
- forwardIp = ip + step;\r
-\r
- if unlikely(forwardIp > mflimit) { goto _last_literals; }\r
-\r
- forwardH = LZ4_HASH_VALUE(forwardIp);\r
- ref = base + HashTable[h];\r
- HashTable[h] = ip - base;\r
-\r
- } while ((ref < ip - MAX_DISTANCE) || (A32(ref) != A32(ip)));\r
-\r
- // Catch up\r
- while ((ip>anchor) && (ref>(BYTE*)source) && unlikely(ip[-1]==ref[-1])) { ip--; ref--; }\r
-\r
- // Encode Literal length\r
- length = ip - anchor;\r
- token = op++;\r
- if (length>=(int)RUN_MASK) { *token=(RUN_MASK<<ML_BITS); len = length-RUN_MASK; for(; len > 254 ; len-=255) *op++ = 255; *op++ = (BYTE)len; }\r
- else *token = (length<<ML_BITS);\r
-\r
- // Copy Literals\r
- LZ4_BLINDCOPY(anchor, op, length);\r
-\r
-_next_match:\r
- // Encode Offset\r
- LZ4_WRITE_LITTLEENDIAN_16(op,ip-ref);\r
-\r
- // Start Counting\r
- ip+=MINMATCH; ref+=MINMATCH; // MinMatch verified\r
- anchor = ip;\r
- while likely(ip<matchlimit-(STEPSIZE-1))\r
- {\r
- UARCH diff = AARCH(ref) ^ AARCH(ip);\r
- if (!diff) { ip+=STEPSIZE; ref+=STEPSIZE; continue; }\r
- ip += LZ4_NbCommonBytes(diff);\r
- goto _endCount;\r
- }\r
- if (LZ4_ARCH64) if ((ip<(matchlimit-3)) && (A32(ref) == A32(ip))) { ip+=4; ref+=4; }\r
- if ((ip<(matchlimit-1)) && (A16(ref) == A16(ip))) { ip+=2; ref+=2; }\r
- if ((ip<matchlimit) && (*ref == *ip)) ip++;\r
-_endCount:\r
-\r
- // Encode MatchLength\r
- len = (ip - anchor);\r
- if (len>=(int)ML_MASK) { *token+=ML_MASK; len-=ML_MASK; for(; len > 509 ; len-=510) { *op++ = 255; *op++ = 255; } if (len > 254) { len-=255; *op++ = 255; } *op++ = (BYTE)len; }\r
- else *token += len;\r
-\r
- // Test end of chunk\r
- if (ip > mflimit) { anchor = ip; break; }\r
-\r
- // Fill table\r
- HashTable[LZ4_HASH_VALUE(ip-2)] = ip - 2 - base;\r
-\r
- // Test next position\r
- ref = base + HashTable[LZ4_HASH_VALUE(ip)];\r
- HashTable[LZ4_HASH_VALUE(ip)] = ip - base;\r
- if ((ref > ip - (MAX_DISTANCE + 1)) && (A32(ref) == A32(ip))) { token = op++; *token=0; goto _next_match; }\r
-\r
- // Prepare next loop\r
- anchor = ip++;\r
- forwardH = LZ4_HASH_VALUE(ip);\r
- }\r
-\r
-_last_literals:\r
- // Encode Last Literals\r
- {\r
- int lastRun = iend - anchor;\r
- if ((LZ4_COMPRESSMIN>0) && (((op - (BYTE*)dest) + lastRun + 1 + ((lastRun-15)/255)) > isize - LZ4_COMPRESSMIN)) return 0;\r
- if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun > 254 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }\r
- else *op++ = (lastRun<<ML_BITS);\r
- memcpy(op, anchor, iend - anchor);\r
- op += iend-anchor;\r
- }\r
-\r
- // End\r
- return (int) (((char*)op)-dest);\r
-}\r
-\r
-\r
-\r
-// Note : this function is valid only if isize < LZ4_64KLIMIT\r
-#define LZ4_64KLIMIT ((1<<16) + (MFLIMIT-1))\r
-#define HASHLOG64K (HASH_LOG+1)\r
-#define HASH64KTABLESIZE (1U<<HASHLOG64K)\r
-#define LZ4_HASH64K_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8)-HASHLOG64K))\r
-#define LZ4_HASH64K_VALUE(p) LZ4_HASH64K_FUNCTION(A32(p))\r
-int LZ4_compress64kCtx(void** ctx,\r
- const char* source,\r
- char* dest,\r
- int isize)\r
-{\r
-#if HEAPMODE\r
- struct refTables *srt = (struct refTables *) (*ctx);\r
- U16* HashTable;\r
-#else\r
- U16 HashTable[HASH64KTABLESIZE] = {0};\r
-#endif\r
-\r
- const BYTE* ip = (BYTE*) source;\r
- const BYTE* anchor = ip;\r
- const BYTE* const base = ip;\r
- const BYTE* const iend = ip + isize;\r
- const BYTE* const mflimit = iend - MFLIMIT;\r
-#define matchlimit (iend - LASTLITERALS)\r
-\r
- BYTE* op = (BYTE*) dest;\r
-\r
- int len, length;\r
- const int skipStrength = SKIPSTRENGTH;\r
- U32 forwardH;\r
-\r
-\r
- // Init\r
- if (isize<MINLENGTH) goto _last_literals;\r
-#if HEAPMODE\r
- if (*ctx == NULL)\r
- {\r
- srt = (struct refTables *) malloc ( sizeof(struct refTables) );\r
- *ctx = (void*) srt;\r
- }\r
- HashTable = (U16*)(srt->hashTable);\r
- memset((void*)HashTable, 0, sizeof(srt->hashTable));\r
-#else\r
- (void) ctx;\r
-#endif\r
-\r
-\r
- // First Byte\r
- ip++; forwardH = LZ4_HASH64K_VALUE(ip);\r
-\r
- // Main Loop\r
- for ( ; ; )\r
- {\r
- int findMatchAttempts = (1U << skipStrength) + 3;\r
- const BYTE* forwardIp = ip;\r
- const BYTE* ref;\r
- BYTE* token;\r
-\r
- // Find a match\r
- do {\r
- U32 h = forwardH;\r
- int step = findMatchAttempts++ >> skipStrength;\r
- ip = forwardIp;\r
- forwardIp = ip + step;\r
-\r
- if (forwardIp > mflimit) { goto _last_literals; }\r
-\r
- forwardH = LZ4_HASH64K_VALUE(forwardIp);\r
- ref = base + HashTable[h];\r
- HashTable[h] = ip - base;\r
-\r
- } while (A32(ref) != A32(ip));\r
-\r
- // Catch up\r
- while ((ip>anchor) && (ref>(BYTE*)source) && (ip[-1]==ref[-1])) { ip--; ref--; }\r
-\r
- // Encode Literal length\r
- length = ip - anchor;\r
- token = op++;\r
- if (length>=(int)RUN_MASK) { *token=(RUN_MASK<<ML_BITS); len = length-RUN_MASK; for(; len > 254 ; len-=255) *op++ = 255; *op++ = (BYTE)len; }\r
- else *token = (length<<ML_BITS);\r
-\r
- // Copy Literals\r
- LZ4_BLINDCOPY(anchor, op, length);\r
-\r
-_next_match:\r
- // Encode Offset\r
- LZ4_WRITE_LITTLEENDIAN_16(op,ip-ref);\r
-\r
- // Start Counting\r
- ip+=MINMATCH; ref+=MINMATCH; // MinMatch verified\r
- anchor = ip;\r
- while (ip<matchlimit-(STEPSIZE-1))\r
- {\r
- UARCH diff = AARCH(ref) ^ AARCH(ip);\r
- if (!diff) { ip+=STEPSIZE; ref+=STEPSIZE; continue; }\r
- ip += LZ4_NbCommonBytes(diff);\r
- goto _endCount;\r
- }\r
- if (LZ4_ARCH64) if ((ip<(matchlimit-3)) && (A32(ref) == A32(ip))) { ip+=4; ref+=4; }\r
- if ((ip<(matchlimit-1)) && (A16(ref) == A16(ip))) { ip+=2; ref+=2; }\r
- if ((ip<matchlimit) && (*ref == *ip)) ip++;\r
-_endCount:\r
-\r
- // Encode MatchLength\r
- len = (ip - anchor);\r
- if (len>=(int)ML_MASK) { *token+=ML_MASK; len-=ML_MASK; for(; len > 509 ; len-=510) { *op++ = 255; *op++ = 255; } if (len > 254) { len-=255; *op++ = 255; } *op++ = (BYTE)len; }\r
- else *token += len;\r
-\r
- // Test end of chunk\r
- if (ip > mflimit) { anchor = ip; break; }\r
-\r
- // Fill table\r
- HashTable[LZ4_HASH64K_VALUE(ip-2)] = ip - 2 - base;\r
-\r
- // Test next position\r
- ref = base + HashTable[LZ4_HASH64K_VALUE(ip)];\r
- HashTable[LZ4_HASH64K_VALUE(ip)] = ip - base;\r
- if (A32(ref) == A32(ip)) { token = op++; *token=0; goto _next_match; }\r
-\r
- // Prepare next loop\r
- anchor = ip++;\r
- forwardH = LZ4_HASH64K_VALUE(ip);\r
- }\r
-\r
-_last_literals:\r
- // Encode Last Literals\r
- {\r
- int lastRun = iend - anchor;\r
- if ((LZ4_COMPRESSMIN>0) && (((op - (BYTE*)dest) + lastRun + 1 + ((lastRun-15)/255)) > isize - LZ4_COMPRESSMIN)) return 0;\r
- if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun > 254 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }\r
- else *op++ = (lastRun<<ML_BITS);\r
- memcpy(op, anchor, iend - anchor);\r
- op += iend-anchor;\r
- }\r
-\r
- // End\r
- return (int) (((char*)op)-dest);\r
-}\r
-\r
-\r
-\r
-int LZ4_compress(const char* source,\r
- char* dest,\r
- int isize)\r
-{\r
-#if HEAPMODE\r
- void* ctx = malloc(sizeof(struct refTables));\r
- int result;\r
- if (isize < LZ4_64KLIMIT)\r
- result = LZ4_compress64kCtx(&ctx, source, dest, isize);\r
- else result = LZ4_compressCtx(&ctx, source, dest, isize);\r
- free(ctx);\r
- return result;\r
-#else\r
- if (isize < (int)LZ4_64KLIMIT) return LZ4_compress64kCtx(NULL, source, dest, isize);\r
- return LZ4_compressCtx(NULL, source, dest, isize);\r
-#endif\r
-}\r
-\r
-\r
-\r
-\r
-//****************************\r
-// Decompression functions\r
-//****************************\r
-\r
-// Note : The decoding functions LZ4_uncompress() and LZ4_uncompress_unknownOutputSize()\r
-// are safe against "buffer overflow" attack type.\r
-// They will never write nor read outside of the provided output buffers.\r
-// LZ4_uncompress_unknownOutputSize() also insures that it will never read outside of the input buffer.\r
-// A corrupted input will produce an error result, a negative int, indicating the position of the error within input stream.\r
-\r
-int LZ4_uncompress(const char* source,\r
- char* dest,\r
- int osize)\r
-{\r
- // Local Variables\r
- const BYTE* restrict ip = (const BYTE*) source;\r
- const BYTE* restrict ref;\r
-\r
- BYTE* restrict op = (BYTE*) dest;\r
- BYTE* const oend = op + osize;\r
- BYTE* cpy;\r
-\r
- BYTE token;\r
-\r
- int len, length;\r
- size_t dec[] ={0, 3, 2, 3, 0, 0, 0, 0};\r
-\r
-\r
- // Main Loop\r
- while (1)\r
- {\r
- // get runlength\r
- token = *ip++;\r
- if ((length=(token>>ML_BITS)) == RUN_MASK) { for (;(len=*ip++)==255;length+=255){} length += len; }\r
-\r
- // copy literals\r
- cpy = op+length;\r
- if unlikely(cpy>oend-COPYLENGTH)\r
- {\r
- if (cpy > oend) goto _output_error; // Error : request to write beyond destination buffer\r
- memcpy(op, ip, length);\r
- ip += length;\r
- break; // Necessarily EOF\r
- }\r
- LZ4_WILDCOPY(ip, op, cpy); ip -= (op-cpy); op = cpy;\r
-\r
- // get offset\r
- LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;\r
- if (ref < (BYTE* const)dest) goto _output_error; // Error : offset create reference outside destination buffer\r
-\r
- // get matchlength\r
- if ((length=(token&ML_MASK)) == ML_MASK) { for (;*ip==255;length+=255) {ip++;} length += *ip++; }\r
-\r
- // copy repeated sequence\r
- if unlikely(op-ref<STEPSIZE)\r
- {\r
-#if LZ4_ARCH64\r
- size_t dec2table[]={0, 0, 0, -1, 0, 1, 2, 3};\r
- size_t dec2 = dec2table[op-ref];\r
-#else\r
- const int dec2 = 0;\r
-#endif\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- ref -= dec[op-ref];\r
- A32(op)=A32(ref); op += STEPSIZE-4;\r
- ref -= dec2;\r
- } else { LZ4_COPYSTEP(ref,op); }\r
- cpy = op + length - (STEPSIZE-4);\r
- if (cpy>oend-COPYLENGTH)\r
- {\r
- if (cpy > oend) goto _output_error; // Error : request to write beyond destination buffer\r
- LZ4_SECURECOPY(ref, op, (oend-COPYLENGTH));\r
- while(op<cpy) *op++=*ref++;\r
- op=cpy;\r
- if (op == oend) break; // Check EOF (should never happen, since last 5 bytes are supposed to be literals)\r
- continue;\r
- }\r
- LZ4_SECURECOPY(ref, op, cpy);\r
- op=cpy; // correction\r
- }\r
-\r
- // end of decoding\r
- return (int) (((char*)ip)-source);\r
-\r
- // write overflow error detected\r
-_output_error:\r
- return (int) (-(((char*)ip)-source));\r
-}\r
-\r
-\r
-int LZ4_uncompress_unknownOutputSize(\r
- const char* source,\r
- char* dest,\r
- int isize,\r
- int maxOutputSize)\r
-{\r
- // Local Variables\r
- const BYTE* restrict ip = (const BYTE*) source;\r
- const BYTE* const iend = ip + isize;\r
- const BYTE* restrict ref;\r
-\r
- BYTE* restrict op = (BYTE*) dest;\r
- BYTE* const oend = op + maxOutputSize;\r
- BYTE* cpy;\r
-\r
- size_t dec[] ={0, 3, 2, 3, 0, 0, 0, 0};\r
-\r
-\r
- // Main Loop\r
- while (ip<iend)\r
- {\r
- BYTE token;\r
- int length;\r
-\r
- // get runlength\r
- token = *ip++;\r
- if ((length=(token>>ML_BITS)) == RUN_MASK) { int s=255; while ((ip<iend) && (s==255)) { s=*ip++; length += s; } }\r
-\r
- // copy literals\r
- cpy = op+length;\r
- if ((cpy>oend-COPYLENGTH) || (ip+length>iend-COPYLENGTH))\r
- {\r
- if (cpy > oend) goto _output_error; // Error : request to write beyond destination buffer\r
- if (ip+length > iend) goto _output_error; // Error : request to read beyond source buffer\r
- memcpy(op, ip, length);\r
- op += length;\r
- ip += length;\r
- if (ip<iend) goto _output_error; // Error : LZ4 format violation\r
- break; // Necessarily EOF, due to parsing restrictions\r
- }\r
- LZ4_WILDCOPY(ip, op, cpy); ip -= (op-cpy); op = cpy;\r
-\r
- // get offset\r
- LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2;\r
- if (ref < (BYTE* const)dest) goto _output_error; // Error : offset creates reference outside of destination buffer\r
-\r
- // get matchlength\r
- if ((length=(token&ML_MASK)) == ML_MASK) { while (ip<iend) { int s = *ip++; length +=s; if (s==255) continue; break; } }\r
-\r
- // copy repeated sequence\r
- if unlikely(op-ref<STEPSIZE)\r
- {\r
-#if LZ4_ARCH64\r
- size_t dec2table[]={0, 0, 0, -1, 0, 1, 2, 3};\r
- size_t dec2 = dec2table[op-ref];\r
-#else\r
- const int dec2 = 0;\r
-#endif\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- *op++ = *ref++;\r
- ref -= dec[op-ref];\r
- A32(op)=A32(ref); op += STEPSIZE-4;\r
- ref -= dec2;\r
- } else { LZ4_COPYSTEP(ref,op); }\r
- cpy = op + length - (STEPSIZE-4);\r
- if (cpy>oend-COPYLENGTH)\r
- {\r
- if (cpy > oend) goto _output_error; // Error : request to write outside of destination buffer\r
- LZ4_SECURECOPY(ref, op, (oend-COPYLENGTH));\r
- while(op<cpy) *op++=*ref++;\r
- op=cpy;\r
- if (op == oend) break; // Check EOF (should never happen, since last 5 bytes are supposed to be literals)\r
- continue;\r
- }\r
- LZ4_SECURECOPY(ref, op, cpy);\r
- op=cpy; // correction\r
- }\r
-\r
- // end of decoding\r
- return (int) (((char*)op)-dest);\r
-\r
- // write overflow error detected\r
-_output_error:\r
- return (int) (-(((char*)ip)-source));\r
-}\r
-\r