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Diffstat (limited to 'vendor/github.com/DataDog/zstd/zstd_v01.c')
| -rw-r--r-- | vendor/github.com/DataDog/zstd/zstd_v01.c | 2158 |
1 files changed, 2158 insertions, 0 deletions
diff --git a/vendor/github.com/DataDog/zstd/zstd_v01.c b/vendor/github.com/DataDog/zstd/zstd_v01.c new file mode 100644 index 000000000..cad2b99b4 --- /dev/null +++ b/vendor/github.com/DataDog/zstd/zstd_v01.c @@ -0,0 +1,2158 @@ +/* + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. + */ + + +/****************************************** +* Includes +******************************************/ +#include <stddef.h> /* size_t, ptrdiff_t */ +#include "zstd_v01.h" +#include "error_private.h" + + +/****************************************** +* Static allocation +******************************************/ +/* You can statically allocate FSE CTable/DTable as a table of unsigned using below macro */ +#define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1<<maxTableLog)) + +/* You can statically allocate Huff0 DTable as a table of unsigned short using below macro */ +#define HUF_DTABLE_SIZE_U16(maxTableLog) (1 + (1<<maxTableLog)) +#define HUF_CREATE_STATIC_DTABLE(DTable, maxTableLog) \ + unsigned short DTable[HUF_DTABLE_SIZE_U16(maxTableLog)] = { maxTableLog } + + +/****************************************** +* Error Management +******************************************/ +#define FSE_LIST_ERRORS(ITEM) \ + ITEM(FSE_OK_NoError) ITEM(FSE_ERROR_GENERIC) \ + ITEM(FSE_ERROR_tableLog_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooSmall) \ + ITEM(FSE_ERROR_dstSize_tooSmall) ITEM(FSE_ERROR_srcSize_wrong)\ + ITEM(FSE_ERROR_corruptionDetected) \ + ITEM(FSE_ERROR_maxCode) + +#define FSE_GENERATE_ENUM(ENUM) ENUM, +typedef enum { FSE_LIST_ERRORS(FSE_GENERATE_ENUM) } FSE_errorCodes; /* enum is exposed, to detect & handle specific errors; compare function result to -enum value */ + + +/****************************************** +* FSE symbol compression API +******************************************/ +/* + This API consists of small unitary functions, which highly benefit from being inlined. + You will want to enable link-time-optimization to ensure these functions are properly inlined in your binary. + Visual seems to do it automatically. + For gcc or clang, you'll need to add -flto flag at compilation and linking stages. + If none of these solutions is applicable, include "fse.c" directly. +*/ + +typedef unsigned FSE_CTable; /* don't allocate that. It's just a way to be more restrictive than void* */ +typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ + +typedef struct +{ + size_t bitContainer; + int bitPos; + char* startPtr; + char* ptr; + char* endPtr; +} FSE_CStream_t; + +typedef struct +{ + ptrdiff_t value; + const void* stateTable; + const void* symbolTT; + unsigned stateLog; +} FSE_CState_t; + +typedef struct +{ + size_t bitContainer; + unsigned bitsConsumed; + const char* ptr; + const char* start; +} FSE_DStream_t; + +typedef struct +{ + size_t state; + const void* table; /* precise table may vary, depending on U16 */ +} FSE_DState_t; + +typedef enum { FSE_DStream_unfinished = 0, + FSE_DStream_endOfBuffer = 1, + FSE_DStream_completed = 2, + FSE_DStream_tooFar = 3 } FSE_DStream_status; /* result of FSE_reloadDStream() */ + /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... ?! */ + + +/**************************************************************** +* 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 +* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ +#define FSE_MAX_MEMORY_USAGE 14 +#define FSE_DEFAULT_MEMORY_USAGE 13 + +/* FSE_MAX_SYMBOL_VALUE : +* Maximum symbol value authorized. +* Required for proper stack allocation */ +#define FSE_MAX_SYMBOL_VALUE 255 + + +/**************************************************************** +* template functions type & suffix +****************************************************************/ +#define FSE_FUNCTION_TYPE BYTE +#define FSE_FUNCTION_EXTENSION + + +/**************************************************************** +* Byte symbol type +****************************************************************/ +typedef struct +{ + unsigned short newState; + unsigned char symbol; + unsigned char nbBits; +} FSE_decode_t; /* size == U32 */ + + + +/**************************************************************** +* Compiler specifics +****************************************************************/ +#ifdef _MSC_VER /* Visual Studio */ +# define FORCE_INLINE static __forceinline +# include <intrin.h> /* For Visual 2005 */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ +#else +# define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) +# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# ifdef __GNUC__ +# define FORCE_INLINE static inline __attribute__((always_inline)) +# else +# define FORCE_INLINE static inline +# endif +# else +# define FORCE_INLINE static +# endif /* __STDC_VERSION__ */ +#endif + + +/**************************************************************** +* Includes +****************************************************************/ +#include <stdlib.h> /* malloc, free, qsort */ +#include <string.h> /* memcpy, memset */ +#include <stdio.h> /* printf (debug) */ + + +#ifndef MEM_ACCESS_MODULE +#define MEM_ACCESS_MODULE +/**************************************************************** +* Basic Types +*****************************************************************/ +#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# include <stdint.h> +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef int16_t S16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; +typedef int64_t S64; +#else +typedef unsigned char BYTE; +typedef unsigned short U16; +typedef signed short S16; +typedef unsigned int U32; +typedef signed int S32; +typedef unsigned long long U64; +typedef signed long long S64; +#endif + +#endif /* MEM_ACCESS_MODULE */ + +/**************************************************************** +* Memory I/O +*****************************************************************/ +/* FSE_FORCE_MEMORY_ACCESS + * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. + * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. + * The below switch allow to select different access method for improved performance. + * Method 0 (default) : use `memcpy()`. Safe and portable. + * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). + * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. + * Method 2 : direct access. This method is portable but violate C standard. + * It can generate buggy code on targets generating assembly depending on alignment. + * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) + * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. + * Prefer these methods in priority order (0 > 1 > 2) + */ +#ifndef FSE_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */ +# if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) +# define FSE_FORCE_MEMORY_ACCESS 2 +# elif (defined(__INTEL_COMPILER) && !defined(WIN32)) || \ + (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) )) +# define FSE_FORCE_MEMORY_ACCESS 1 +# endif +#endif + + +static unsigned FSE_32bits(void) +{ + return sizeof(void*)==4; +} + +static unsigned FSE_isLittleEndian(void) +{ + const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ + return one.c[0]; +} + +#if defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==2) + +static U16 FSE_read16(const void* memPtr) { return *(const U16*) memPtr; } +static U32 FSE_read32(const void* memPtr) { return *(const U32*) memPtr; } +static U64 FSE_read64(const void* memPtr) { return *(const U64*) memPtr; } + +#elif defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==1) + +/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ +/* currently only defined for gcc and icc */ +typedef union { U16 u16; U32 u32; U64 u64; } __attribute__((packed)) unalign; + +static U16 FSE_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } +static U32 FSE_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } +static U64 FSE_read64(const void* ptr) { return ((const unalign*)ptr)->u64; } + +#else + +static U16 FSE_read16(const void* memPtr) +{ + U16 val; memcpy(&val, memPtr, sizeof(val)); return val; +} + +static U32 FSE_read32(const void* memPtr) +{ + U32 val; memcpy(&val, memPtr, sizeof(val)); return val; +} + +static U64 FSE_read64(const void* memPtr) +{ + U64 val; memcpy(&val, memPtr, sizeof(val)); return val; +} + +#endif // FSE_FORCE_MEMORY_ACCESS + +static U16 FSE_readLE16(const void* memPtr) +{ + if (FSE_isLittleEndian()) + return FSE_read16(memPtr); + else + { + const BYTE* p = (const BYTE*)memPtr; + return (U16)(p[0] + (p[1]<<8)); + } +} + +static U32 FSE_readLE32(const void* memPtr) +{ + if (FSE_isLittleEndian()) + return FSE_read32(memPtr); + else + { + const BYTE* p = (const BYTE*)memPtr; + return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24)); + } +} + + +static U64 FSE_readLE64(const void* memPtr) +{ + if (FSE_isLittleEndian()) + return FSE_read64(memPtr); + else + { + const BYTE* p = (const BYTE*)memPtr; + return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24) + + ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56)); + } +} + +static size_t FSE_readLEST(const void* memPtr) +{ + if (FSE_32bits()) + return (size_t)FSE_readLE32(memPtr); + else + return (size_t)FSE_readLE64(memPtr); +} + + + +/**************************************************************** +* Constants +*****************************************************************/ +#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE-2) +#define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG) +#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1) +#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2) +#define FSE_MIN_TABLELOG 5 + +#define FSE_TABLELOG_ABSOLUTE_MAX 15 +#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX +#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported" +#endif + + +/**************************************************************** +* Error Management +****************************************************************/ +#define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ + + +/**************************************************************** +* Complex types +****************************************************************/ +typedef struct +{ + int deltaFindState; + U32 deltaNbBits; +} FSE_symbolCompressionTransform; /* total 8 bytes */ + +typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)]; + +/**************************************************************** +* Internal functions +****************************************************************/ +FORCE_INLINE unsigned FSE_highbit32 (U32 val) +{ +# if defined(_MSC_VER) /* Visual */ + unsigned long r; + _BitScanReverse ( &r, val ); + return (unsigned) r; +# elif defined(__GNUC__) && (GCC_VERSION >= 304) /* GCC Intrinsic */ + return 31 - __builtin_clz (val); +# else /* Software version */ + static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 }; + U32 v = val; + unsigned r; + v |= v >> 1; + v |= v >> 2; + v |= v >> 4; + v |= v >> 8; + v |= v >> 16; + r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27]; + return r; +# endif +} + + +/**************************************************************** +* Templates +****************************************************************/ +/* + designed to be included + for type-specific functions (template emulation in C) + Objective is to write these functions only once, for improved maintenance +*/ + +/* safety checks */ +#ifndef FSE_FUNCTION_EXTENSION +# error "FSE_FUNCTION_EXTENSION must be defined" +#endif +#ifndef FSE_FUNCTION_TYPE +# error "FSE_FUNCTION_TYPE must be defined" +#endif + +/* Function names */ +#define FSE_CAT(X,Y) X##Y +#define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y) +#define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y) + + + +static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; } + +#define FSE_DECODE_TYPE FSE_decode_t + + +typedef struct { + U16 tableLog; + U16 fastMode; +} FSE_DTableHeader; /* sizeof U32 */ + +static size_t FSE_buildDTable +(FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog) +{ + void* ptr = dt; + FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; + FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*)(ptr) + 1; /* because dt is unsigned, 32-bits aligned on 32-bits */ + const U32 tableSize = 1 << tableLog; + const U32 tableMask = tableSize-1; + const U32 step = FSE_tableStep(tableSize); + U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1]; + U32 position = 0; + U32 highThreshold = tableSize-1; + const S16 largeLimit= (S16)(1 << (tableLog-1)); + U32 noLarge = 1; + U32 s; + + /* Sanity Checks */ + if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_maxSymbolValue_tooLarge; + if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_tableLog_tooLarge; + + /* Init, lay down lowprob symbols */ + DTableH[0].tableLog = (U16)tableLog; + for (s=0; s<=maxSymbolValue; s++) + { + if (normalizedCounter[s]==-1) + { + tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; + symbolNext[s] = 1; + } + else + { + if (normalizedCounter[s] >= largeLimit) noLarge=0; + symbolNext[s] = normalizedCounter[s]; + } + } + + /* Spread symbols */ + for (s=0; s<=maxSymbolValue; s++) + { + int i; + for (i=0; i<normalizedCounter[s]; i++) + { + tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; + position = (position + step) & tableMask; + while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */ + } + } + + if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* position must reach all cells once, otherwise normalizedCounter is incorrect */ + + /* Build Decoding table */ + { + U32 i; + for (i=0; i<tableSize; i++) + { + FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol); + U16 nextState = symbolNext[symbol]++; + tableDecode[i].nbBits = (BYTE) (tableLog - FSE_highbit32 ((U32)nextState) ); + tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize); + } + } + + DTableH->fastMode = (U16)noLarge; + return 0; +} + + +/****************************************** +* FSE byte symbol +******************************************/ +#ifndef FSE_COMMONDEFS_ONLY + +static unsigned FSE_isError(size_t code) { return (code > (size_t)(-FSE_ERROR_maxCode)); } + +static short FSE_abs(short a) +{ + return a<0? -a : a; +} + + +/**************************************************************** +* Header bitstream management +****************************************************************/ +static size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, + const void* headerBuffer, size_t hbSize) +{ + const BYTE* const istart = (const BYTE*) headerBuffer; + const BYTE* const iend = istart + hbSize; + const BYTE* ip = istart; + int nbBits; + int remaining; + int threshold; + U32 bitStream; + int bitCount; + unsigned charnum = 0; + int previous0 = 0; + + if (hbSize < 4) return (size_t)-FSE_ERROR_srcSize_wrong; + bitStream = FSE_readLE32(ip); + nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ + if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return (size_t)-FSE_ERROR_tableLog_tooLarge; + bitStream >>= 4; + bitCount = 4; + *tableLogPtr = nbBits; + remaining = (1<<nbBits)+1; + threshold = 1<<nbBits; + nbBits++; + + while ((remaining>1) && (charnum<=*maxSVPtr)) + { + if (previous0) + { + unsigned n0 = charnum; + while ((bitStream & 0xFFFF) == 0xFFFF) + { + n0+=24; + if (ip < iend-5) + { + ip+=2; + bitStream = FSE_readLE32(ip) >> bitCount; + } + else + { + bitStream >>= 16; + bitCount+=16; + } + } + while ((bitStream & 3) == 3) + { + n0+=3; + bitStream>>=2; + bitCount+=2; + } + n0 += bitStream & 3; + bitCount += 2; + if (n0 > *maxSVPtr) return (size_t)-FSE_ERROR_maxSymbolValue_tooSmall; + while (charnum < n0) normalizedCounter[charnum++] = 0; + if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) + { + ip += bitCount>>3; + bitCount &= 7; + bitStream = FSE_readLE32(ip) >> bitCount; + } + else + bitStream >>= 2; + } + { + const short max = (short)((2*threshold-1)-remaining); + short count; + + if ((bitStream & (threshold-1)) < (U32)max) + { + count = (short)(bitStream & (threshold-1)); + bitCount += nbBits-1; + } + else + { + count = (short)(bitStream & (2*threshold-1)); + if (count >= threshold) count -= max; + bitCount += nbBits; + } + + count--; /* extra accuracy */ + remaining -= FSE_abs(count); + normalizedCounter[charnum++] = count; + previous0 = !count; + while (remaining < threshold) + { + nbBits--; + threshold >>= 1; + } + + { + if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) + { + ip += bitCount>>3; + bitCount &= 7; + } + else + { + bitCount -= (int)(8 * (iend - 4 - ip)); + ip = iend - 4; + } + bitStream = FSE_readLE32(ip) >> (bitCount & 31); + } + } + } + if (remaining != 1) return (size_t)-FSE_ERROR_GENERIC; + *maxSVPtr = charnum-1; + + ip += (bitCount+7)>>3; + if ((size_t)(ip-istart) > hbSize) return (size_t)-FSE_ERROR_srcSize_wrong; + return ip-istart; +} + + +/********************************************************* +* Decompression (Byte symbols) +*********************************************************/ +static size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue) +{ + void* ptr = dt; + FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; + FSE_decode_t* const cell = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ + + DTableH->tableLog = 0; + DTableH->fastMode = 0; + + cell->newState = 0; + cell->symbol = symbolValue; + cell->nbBits = 0; + + return 0; +} + + +static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits) +{ + void* ptr = dt; + FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; + FSE_decode_t* const dinfo = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ + const unsigned tableSize = 1 << nbBits; + const unsigned tableMask = tableSize - 1; + const unsigned maxSymbolValue = tableMask; + unsigned s; + + /* Sanity checks */ + if (nbBits < 1) return (size_t)-FSE_ERROR_GENERIC; /* min size */ + + /* Build Decoding Table */ + DTableH->tableLog = (U16)nbBits; + DTableH->fastMode = 1; + for (s=0; s<=maxSymbolValue; s++) + { + dinfo[s].newState = 0; + dinfo[s].symbol = (BYTE)s; + dinfo[s].nbBits = (BYTE)nbBits; + } + + return 0; +} + + +/* FSE_initDStream + * Initialize a FSE_DStream_t. + * srcBuffer must point at the beginning of an FSE block. + * The function result is the size of the FSE_block (== srcSize). + * If srcSize is too small, the function will return an errorCode; + */ +static size_t FSE_initDStream(FSE_DStream_t* bitD, const void* srcBuffer, size_t srcSize) +{ + if (srcSize < 1) return (size_t)-FSE_ERROR_srcSize_wrong; + + if (srcSize >= sizeof(size_t)) + { + U32 contain32; + bitD->start = (const char*)srcBuffer; + bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(size_t); + bitD->bitContainer = FSE_readLEST(bitD->ptr); + contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; + if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ + bitD->bitsConsumed = 8 - FSE_highbit32(contain32); + } + else + { + U32 contain32; + bitD->start = (const char*)srcBuffer; + bitD->ptr = bitD->start; + bitD->bitContainer = *(const BYTE*)(bitD->start); + switch(srcSize) + { + case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16); + /* fallthrough */ + case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24); + /* fallthrough */ + case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32); + /* fallthrough */ + case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; + /* fallthrough */ + case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; + /* fallthrough */ + case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8; + /* fallthrough */ + default:; + } + contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; + if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ + bitD->bitsConsumed = 8 - FSE_highbit32(contain32); + bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8; + } + + return srcSize; +} + + +/*!FSE_lookBits + * Provides next n bits from the bitContainer. + * bitContainer is not modified (bits are still present for next read/look) + * On 32-bits, maxNbBits==25 + * On 64-bits, maxNbBits==57 + * return : value extracted. + */ +static size_t FSE_lookBits(FSE_DStream_t* bitD, U32 nbBits) +{ + const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; + return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask); +} + +static size_t FSE_lookBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ +{ + const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; + return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask); +} + +static void FSE_skipBits(FSE_DStream_t* bitD, U32 nbBits) +{ + bitD->bitsConsumed += nbBits; +} + + +/*!FSE_readBits + * Read next n bits from the bitContainer. + * On 32-bits, don't read more than maxNbBits==25 + * On 64-bits, don't read more than maxNbBits==57 + * Use the fast variant *only* if n >= 1. + * return : value extracted. + */ +static size_t FSE_readBits(FSE_DStream_t* bitD, U32 nbBits) +{ + size_t value = FSE_lookBits(bitD, nbBits); + FSE_skipBits(bitD, nbBits); + return value; +} + +static size_t FSE_readBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ +{ + size_t value = FSE_lookBitsFast(bitD, nbBits); + FSE_skipBits(bitD, nbBits); + return value; +} + +static unsigned FSE_reloadDStream(FSE_DStream_t* bitD) +{ + if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */ + return FSE_DStream_tooFar; + + if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) + { + bitD->ptr -= bitD->bitsConsumed >> 3; + bitD->bitsConsumed &= 7; + bitD->bitContainer = FSE_readLEST(bitD->ptr); + return FSE_DStream_unfinished; + } + if (bitD->ptr == bitD->start) + { + if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return FSE_DStream_endOfBuffer; + return FSE_DStream_completed; + } + { + U32 nbBytes = bitD->bitsConsumed >> 3; + U32 result = FSE_DStream_unfinished; + if (bitD->ptr - nbBytes < bitD->start) + { + nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */ + result = FSE_DStream_endOfBuffer; + } + bitD->ptr -= nbBytes; + bitD->bitsConsumed -= nbBytes*8; + bitD->bitContainer = FSE_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */ + return result; + } +} + + +static void FSE_initDState(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD, const FSE_DTable* dt) +{ + const void* ptr = dt; + const FSE_DTableHeader* const DTableH = (const FSE_DTableHeader*)ptr; + DStatePtr->state = FSE_readBits(bitD, DTableH->tableLog); + FSE_reloadDStream(bitD); + DStatePtr->table = dt + 1; +} + +static BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) +{ + const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; + const U32 nbBits = DInfo.nbBits; + BYTE symbol = DInfo.symbol; + size_t lowBits = FSE_readBits(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +static BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) +{ + const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; + const U32 nbBits = DInfo.nbBits; + BYTE symbol = DInfo.symbol; + size_t lowBits = FSE_readBitsFast(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +/* FSE_endOfDStream + Tells if bitD has reached end of bitStream or not */ + +static unsigned FSE_endOfDStream(const FSE_DStream_t* bitD) +{ + return ((bitD->ptr == bitD->start) && (bitD->bitsConsumed == sizeof(bitD->bitContainer)*8)); +} + +static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr) +{ + return DStatePtr->state == 0; +} + + +FORCE_INLINE size_t FSE_decompress_usingDTable_generic( + void* dst, size_t maxDstSize, + const void* cSrc, size_t cSrcSize, + const FSE_DTable* dt, const unsigned fast) +{ + BYTE* const ostart = (BYTE*) dst; + BYTE* op = ostart; + BYTE* const omax = op + maxDstSize; + BYTE* const olimit = omax-3; + + FSE_DStream_t bitD; + FSE_DState_t state1; + FSE_DState_t state2; + size_t errorCode; + + /* Init */ + errorCode = FSE_initDStream(&bitD, cSrc, cSrcSize); /* replaced last arg by maxCompressed Size */ + if (FSE_isError(errorCode)) return errorCode; + + FSE_initDState(&state1, &bitD, dt); + FSE_initDState(&state2, &bitD, dt); + +#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) + + /* 4 symbols per loop */ + for ( ; (FSE_reloadDStream(&bitD)==FSE_DStream_unfinished) && (op<olimit) ; op+=4) + { + op[0] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + FSE_reloadDStream(&bitD); + + op[1] = FSE_GETSYMBOL(&state2); + + if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + { if (FSE_reloadDStream(&bitD) > FSE_DStream_unfinished) { op+=2; break; } } + + op[2] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + FSE_reloadDStream(&bitD); + + op[3] = FSE_GETSYMBOL(&state2); + } + + /* tail */ + /* note : FSE_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly FSE_DStream_completed */ + while (1) + { + if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) ) + break; + + *op++ = FSE_GETSYMBOL(&state1); + + if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) ) + break; + + *op++ = FSE_GETSYMBOL(&state2); + } + + /* end ? */ + if (FSE_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2)) + return op-ostart; + + if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ + + return (size_t)-FSE_ERROR_corruptionDetected; +} + + +static size_t FSE_decompress_usingDTable(void* dst, size_t originalSize, + const void* cSrc, size_t cSrcSize, + const FSE_DTable* dt) +{ + FSE_DTableHeader DTableH; + memcpy(&DTableH, dt, sizeof(DTableH)); /* memcpy() into local variable, to avoid strict aliasing warning */ + + /* select fast mode (static) */ + if (DTableH.fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); +} + + +static size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) +{ + const BYTE* const istart = (const BYTE*)cSrc; + const BYTE* ip = istart; + short counting[FSE_MAX_SYMBOL_VALUE+1]; + DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */ + unsigned tableLog; + unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; + size_t errorCode; + + if (cSrcSize<2) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ + + /* normal FSE decoding mode */ + errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize); + if (FSE_isError(errorCode)) return errorCode; + if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ + ip += errorCode; + cSrcSize -= errorCode; + + errorCode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog); + if (FSE_isError(errorCode)) return errorCode; + + /* always return, even if it is an error code */ + return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt); +} + + + +/* ******************************************************* +* Huff0 : Huffman block compression +*********************************************************/ +#define HUF_MAX_SYMBOL_VALUE 255 +#define HUF_DEFAULT_TABLELOG 12 /* used by default, when not specified */ +#define HUF_MAX_TABLELOG 12 /* max possible tableLog; for allocation purpose; can be modified */ +#define HUF_ABSOLUTEMAX_TABLELOG 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ +#if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG) +# error "HUF_MAX_TABLELOG is too large !" +#endif + +typedef struct HUF_CElt_s { + U16 val; + BYTE nbBits; +} HUF_CElt ; + +typedef struct nodeElt_s { + U32 count; + U16 parent; + BYTE byte; + BYTE nbBits; +} nodeElt; + + +/* ******************************************************* +* Huff0 : Huffman block decompression +*********************************************************/ +typedef struct { + BYTE byte; + BYTE nbBits; +} HUF_DElt; + +static size_t HUF_readDTable (U16* DTable, const void* src, size_t srcSize) +{ + BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1]; + U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1]; /* large enough for values from 0 to 16 */ + U32 weightTotal; + U32 maxBits; + const BYTE* ip = (const BYTE*) src; + size_t iSize; + size_t oSize; + U32 n; + U32 nextRankStart; + void* ptr = DTable+1; + HUF_DElt* const dt = (HUF_DElt*)ptr; + + if (!srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; + iSize = ip[0]; + + FSE_STATIC_ASSERT(sizeof(HUF_DElt) == sizeof(U16)); /* if compilation fails here, assertion is false */ + //memset(huffWeight, 0, sizeof(huffWeight)); /* should not be necessary, but some analyzer complain ... */ + if (iSize >= 128) /* special header */ + { + if (iSize >= (242)) /* RLE */ + { + static int l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 }; + oSize = l[iSize-242]; + memset(huffWeight, 1, sizeof(huffWeight)); + iSize = 0; + } + else /* Incompressible */ + { + oSize = iSize - 127; + iSize = ((oSize+1)/2); + if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; + ip += 1; + for (n=0; n<oSize; n+=2) + { + huffWeight[n] = ip[n/2] >> 4; + huffWeight[n+1] = ip[n/2] & 15; + } + } + } + else /* header compressed with FSE (normal case) */ + { + if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; + oSize = FSE_decompress(huffWeight, HUF_MAX_SYMBOL_VALUE, ip+1, iSize); /* max 255 values decoded, last one is implied */ + if (FSE_isError(oSize)) return oSize; + } + + /* collect weight stats */ + memset(rankVal, 0, sizeof(rankVal)); + weightTotal = 0; + for (n=0; n<oSize; n++) + { + if (huffWeight[n] >= HUF_ABSOLUTEMAX_TABLELOG) return (size_t)-FSE_ERROR_corruptionDetected; + rankVal[huffWeight[n]]++; + weightTotal += (1 << huffWeight[n]) >> 1; + } + if (weightTotal == 0) return (size_t)-FSE_ERROR_corruptionDetected; + + /* get last non-null symbol weight (implied, total must be 2^n) */ + maxBits = FSE_highbit32(weightTotal) + 1; + if (maxBits > DTable[0]) return (size_t)-FSE_ERROR_tableLog_tooLarge; /* DTable is too small */ + DTable[0] = (U16)maxBits; + { + U32 total = 1 << maxBits; + U32 rest = total - weightTotal; + U32 verif = 1 << FSE_highbit32(rest); + U32 lastWeight = FSE_highbit32(rest) + 1; + if (verif != rest) return (size_t)-FSE_ERROR_corruptionDetected; /* last value must be a clean power of 2 */ + huffWeight[oSize] = (BYTE)lastWeight; + rankVal[lastWeight]++; + } + + /* check tree construction validity */ + if ((rankVal[1] < 2) || (rankVal[1] & 1)) return (size_t)-FSE_ERROR_corruptionDetected; /* by construction : at least 2 elts of rank 1, must be even */ + + /* Prepare ranks */ + nextRankStart = 0; + for (n=1; n<=maxBits; n++) + { + U32 current = nextRankStart; + nextRankStart += (rankVal[n] << (n-1)); + rankVal[n] = current; + } + + /* fill DTable */ + for (n=0; n<=oSize; n++) + { + const U32 w = huffWeight[n]; + const U32 length = (1 << w) >> 1; + U32 i; + HUF_DElt D; + D.byte = (BYTE)n; D.nbBits = (BYTE)(maxBits + 1 - w); + for (i = rankVal[w]; i < rankVal[w] + length; i++) + dt[i] = D; + rankVal[w] += length; + } + + return iSize+1; +} + + +static BYTE HUF_decodeSymbol(FSE_DStream_t* Dstream, const HUF_DElt* dt, const U32 dtLog) +{ + const size_t val = FSE_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ + const BYTE c = dt[val].byte; + FSE_skipBits(Dstream, dt[val].nbBits); + return c; +} + +static size_t HUF_decompress_usingDTable( /* -3% slower when non static */ + void* dst, size_t maxDstSize, + const void* cSrc, size_t cSrcSize, + const U16* DTable) +{ + BYTE* const ostart = (BYTE*) dst; + BYTE* op = ostart; + BYTE* const omax = op + maxDstSize; + BYTE* const olimit = omax-15; + + const void* ptr = DTable; + const HUF_DElt* const dt = (const HUF_DElt*)(ptr)+1; + const U32 dtLog = DTable[0]; + size_t errorCode; + U32 reloadStatus; + + /* Init */ + + const U16* jumpTable = (const U16*)cSrc; + const size_t length1 = FSE_readLE16(jumpTable); + const size_t length2 = FSE_readLE16(jumpTable+1); + const size_t length3 = FSE_readLE16(jumpTable+2); + const size_t length4 = cSrcSize - 6 - length1 - length2 - length3; // check coherency !! + const char* const start1 = (const char*)(cSrc) + 6; + const char* const start2 = start1 + length1; + const char* const start3 = start2 + length2; + const char* const start4 = start3 + length3; + FSE_DStream_t bitD1, bitD2, bitD3, bitD4; + + if (length1+length2+length3+6 >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; + + errorCode = FSE_initDStream(&bitD1, start1, length1); + if (FSE_isError(errorCode)) return errorCode; + errorCode = FSE_initDStream(&bitD2, start2, length2); + if (FSE_isError(errorCode)) return errorCode; + errorCode = FSE_initDStream(&bitD3, start3, length3); + if (FSE_isError(errorCode)) return errorCode; + errorCode = FSE_initDStream(&bitD4, start4, length4); + if (FSE_isError(errorCode)) return errorCode; + + reloadStatus=FSE_reloadDStream(&bitD2); + + /* 16 symbols per loop */ + for ( ; (reloadStatus<FSE_DStream_completed) && (op<olimit); /* D2-3-4 are supposed to be synchronized and finish together */ + op+=16, reloadStatus = FSE_reloadDStream(&bitD2) | FSE_reloadDStream(&bitD3) | FSE_reloadDStream(&bitD4), FSE_reloadDStream(&bitD1)) + { +#define HUF_DECODE_SYMBOL_0(n, Dstream) \ + op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); + +#define HUF_DECODE_SYMBOL_1(n, Dstream) \ + op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ + if (FSE_32bits() && (HUF_MAX_TABLELOG>12)) FSE_reloadDStream(&Dstream) + +#define HUF_DECODE_SYMBOL_2(n, Dstream) \ + op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ + if (FSE_32bits()) FSE_reloadDStream(&Dstream) + + HUF_DECODE_SYMBOL_1( 0, bitD1); + HUF_DECODE_SYMBOL_1( 1, bitD2); + HUF_DECODE_SYMBOL_1( 2, bitD3); + HUF_DECODE_SYMBOL_1( 3, bitD4); + HUF_DECODE_SYMBOL_2( 4, bitD1); + HUF_DECODE_SYMBOL_2( 5, bitD2); + HUF_DECODE_SYMBOL_2( 6, bitD3); + HUF_DECODE_SYMBOL_2( 7, bitD4); + HUF_DECODE_SYMBOL_1( 8, bitD1); + HUF_DECODE_SYMBOL_1( 9, bitD2); + HUF_DECODE_SYMBOL_1(10, bitD3); + HUF_DECODE_SYMBOL_1(11, bitD4); + HUF_DECODE_SYMBOL_0(12, bitD1); + HUF_DECODE_SYMBOL_0(13, bitD2); + HUF_DECODE_SYMBOL_0(14, bitD3); + HUF_DECODE_SYMBOL_0(15, bitD4); + } + + if (reloadStatus!=FSE_DStream_completed) /* not complete : some bitStream might be FSE_DStream_unfinished */ + return (size_t)-FSE_ERROR_corruptionDetected; + + /* tail */ + { + // bitTail = bitD1; // *much* slower : -20% !??! + FSE_DStream_t bitTail; + bitTail.ptr = bitD1.ptr; + bitTail.bitsConsumed = bitD1.bitsConsumed; + bitTail.bitContainer = bitD1.bitContainer; // required in case of FSE_DStream_endOfBuffer + bitTail.start = start1; + for ( ; (FSE_reloadDStream(&bitTail) < FSE_DStream_completed) && (op<omax) ; op++) + { + HUF_DECODE_SYMBOL_0(0, bitTail); + } + + if (FSE_endOfDStream(&bitTail)) + return op-ostart; + } + + if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ + + return (size_t)-FSE_ERROR_corruptionDetected; +} + + +static size_t HUF_decompress (void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) +{ + HUF_CREATE_STATIC_DTABLE(DTable, HUF_MAX_TABLELOG); + const BYTE* ip = (const BYTE*) cSrc; + size_t errorCode; + + errorCode = HUF_readDTable (DTable, cSrc, cSrcSize); + if (FSE_isError(errorCode)) return errorCode; + if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; + ip += errorCode; + cSrcSize -= errorCode; + + return HUF_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, DTable); +} + + +#endif /* FSE_COMMONDEFS_ONLY */ + +/* + zstd - standard compression library + Copyright (C) 2014-2015, Yann Collet. + + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + 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 : + - zstd source repository : https://github.com/Cyan4973/zstd + - ztsd 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 */ +#define ZSTD_MEMORY_USAGE 17 + + +/************************************** + CPU Feature Detection +**************************************/ +/* + * Automated efficient unaligned memory access detection + * Based on known hardware architectures + * This list will be updated thanks to feedbacks + */ +#if defined(CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS) \ + || defined(__ARM_FEATURE_UNALIGNED) \ + || defined(__i386__) || defined(__x86_64__) \ + || defined(_M_IX86) || defined(_M_X64) \ + || defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_8__) \ + || (defined(_M_ARM) && (_M_ARM >= 7)) +# define ZSTD_UNALIGNED_ACCESS 1 +#else +# define ZSTD_UNALIGNED_ACCESS 0 +#endif + + +/******************************************************** +* Includes +*********************************************************/ +#include <stdlib.h> /* calloc */ +#include <string.h> /* memcpy, memmove */ +#include <stdio.h> /* debug : printf */ + + +/******************************************************** +* Compiler specifics +*********************************************************/ +#ifdef __AVX2__ +# include <immintrin.h> /* AVX2 intrinsics */ +#endif + +#ifdef _MSC_VER /* Visual Studio */ +# include <intrin.h> /* For Visual 2005 */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +# pragma warning(disable : 4324) /* disable: C4324: padded structure */ +#endif + + +#ifndef MEM_ACCESS_MODULE +#define MEM_ACCESS_MODULE +/******************************************************** +* Basic Types +*********************************************************/ +#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# include <stdint.h> +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef int16_t S16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; +#else +typedef unsigned char BYTE; +typedef unsigned short U16; +typedef signed short S16; +typedef unsigned int U32; +typedef signed int S32; +typedef unsigned long long U64; +#endif + +#endif /* MEM_ACCESS_MODULE */ + + +/******************************************************** +* Constants +*********************************************************/ +static const U32 ZSTD_magicNumber = 0xFD2FB51E; /* 3rd version : seqNb header */ + +#define HASH_LOG (ZSTD_MEMORY_USAGE - 2) +#define HASH_TABLESIZE (1 << HASH_LOG) +#define HASH_MASK (HASH_TABLESIZE - 1) + +#define KNUTH 2654435761 + +#define BIT7 128 +#define BIT6 64 +#define BIT5 32 +#define BIT4 16 + +#define KB *(1 <<10) +#define MB *(1 <<20) +#define GB *(1U<<30) + +#define BLOCKSIZE (128 KB) /* define, for static allocation */ + +#define WORKPLACESIZE (BLOCKSIZE*3) +#define MINMATCH 4 +#define MLbits 7 +#define LLbits 6 +#define Offbits 5 +#define MaxML ((1<<MLbits )-1) +#define MaxLL ((1<<LLbits )-1) +#define MaxOff ((1<<Offbits)-1) +#define LitFSELog 11 +#define MLFSELog 10 +#define LLFSELog 10 +#define OffFSELog 9 +#define MAX(a,b) ((a)<(b)?(b):(a)) +#define MaxSeq MAX(MaxLL, MaxML) + +#define LITERAL_NOENTROPY 63 +#define COMMAND_NOENTROPY 7 /* to remove */ + +#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) + +static const size_t ZSTD_blockHeaderSize = 3; +static const size_t ZSTD_frameHeaderSize = 4; + + +/******************************************************** +* Memory operations +*********************************************************/ +static unsigned ZSTD_32bits(void) { return sizeof(void*)==4; } + +static unsigned ZSTD_isLittleEndian(void) +{ + const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ + return one.c[0]; +} + +static U16 ZSTD_read16(const void* p) { U16 r; memcpy(&r, p, sizeof(r)); return r; } + +static U32 ZSTD_read32(const void* p) { U32 r; memcpy(&r, p, sizeof(r)); return r; } + +static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); } + +static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); } + +#define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; } + +static void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length) +{ + const BYTE* ip = (const BYTE*)src; + BYTE* op = (BYTE*)dst; + BYTE* const oend = op + length; + while (op < oend) COPY8(op, ip); +} + +static U16 ZSTD_readLE16(const void* memPtr) +{ + if (ZSTD_isLittleEndian()) return ZSTD_read16(memPtr); + else + { + const BYTE* p = (const BYTE*)memPtr; + return (U16)((U16)p[0] + ((U16)p[1]<<8)); + } +} + + +static U32 ZSTD_readLE32(const void* memPtr) +{ + if (ZSTD_isLittleEndian()) + return ZSTD_read32(memPtr); + else + { + const BYTE* p = (const BYTE*)memPtr; + return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24)); + } +} + +static U32 ZSTD_readBE32(const void* memPtr) +{ + const BYTE* p = (const BYTE*)memPtr; + return (U32)(((U32)p[0]<<24) + ((U32)p[1]<<16) + ((U32)p[2]<<8) + ((U32)p[3]<<0)); +} + + +/************************************** +* Local structures +***************************************/ +typedef struct ZSTD_Cctx_s ZSTD_Cctx; + +typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t; + +typedef struct +{ + blockType_t blockType; + U32 origSize; +} blockProperties_t; + +typedef struct { + void* buffer; + U32* offsetStart; + U32* offset; + BYTE* offCodeStart; + BYTE* offCode; + BYTE* litStart; + BYTE* lit; + BYTE* litLengthStart; + BYTE* litLength; + BYTE* matchLengthStart; + BYTE* matchLength; + BYTE* dumpsStart; + BYTE* dumps; +} seqStore_t; + + +typedef struct ZSTD_Cctx_s +{ + const BYTE* base; + U32 current; + U32 nextUpdate; + seqStore_t seqStore; +#ifdef __AVX2__ + __m256i hashTable[HASH_TABLESIZE>>3]; +#else + U32 hashTable[HASH_TABLESIZE]; +#endif + BYTE buffer[WORKPLACESIZE]; +} cctxi_t; + + + + +/************************************** +* Error Management +**************************************/ +/* published entry point */ +unsigned ZSTDv01_isError(size_t code) { return ERR_isError(code); } + + +/************************************** +* Tool functions +**************************************/ +#define ZSTD_VERSION_MAJOR 0 /* for breaking interface changes */ +#define ZSTD_VERSION_MINOR 1 /* for new (non-breaking) interface capabilities */ +#define ZSTD_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */ +#define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) + +/************************************************************** +* Decompression code +**************************************************************/ + +static size_t ZSTDv01_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr) +{ + const BYTE* const in = (const BYTE* const)src; + BYTE headerFlags; + U32 cSize; + + if (srcSize < 3) return ERROR(srcSize_wrong); + + headerFlags = *in; + cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16); + + bpPtr->blockType = (blockType_t)(headerFlags >> 6); + bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0; + + if (bpPtr->blockType == bt_end) return 0; + if (bpPtr->blockType == bt_rle) return 1; + return cSize; +} + + +static size_t ZSTD_copyUncompressedBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize) +{ + if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall); + memcpy(dst, src, srcSize); + return srcSize; +} + + +static size_t ZSTD_decompressLiterals(void* ctx, + void* dst, size_t maxDstSize, + const void* src, size_t srcSize) +{ + BYTE* op = (BYTE*)dst; + BYTE* const oend = op + maxDstSize; + const BYTE* ip = (const BYTE*)src; + size_t errorCode; + size_t litSize; + + /* check : minimum 2, for litSize, +1, for content */ + if (srcSize <= 3) return ERROR(corruption_detected); + + litSize = ip[1] + (ip[0]<<8); + litSize += ((ip[-3] >> 3) & 7) << 16; // mmmmh.... + op = oend - litSize; + + (void)ctx; + if (litSize > maxDstSize) return ERROR(dstSize_tooSmall); + errorCode = HUF_decompress(op, litSize, ip+2, srcSize-2); + if (FSE_isError(errorCode)) return ERROR(GENERIC); + return litSize; +} + + +static size_t ZSTDv01_decodeLiteralsBlock(void* ctx, + void* dst, size_t maxDstSize, + const BYTE** litStart, size_t* litSize, + const void* src, size_t srcSize) +{ + const BYTE* const istart = (const BYTE* const)src; + const BYTE* ip = istart; + BYTE* const ostart = (BYTE* const)dst; + BYTE* const oend = ostart + maxDstSize; + blockProperties_t litbp; + + size_t litcSize = ZSTDv01_getcBlockSize(src, srcSize, &litbp); + if (ZSTDv01_isError(litcSize)) return litcSize; + if (litcSize > srcSize - ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); + ip += ZSTD_blockHeaderSize; + + switch(litbp.blockType) + { + case bt_raw: + *litStart = ip; + ip += litcSize; + *litSize = litcSize; + break; + case bt_rle: + { + size_t rleSize = litbp.origSize; + if (rleSize>maxDstSize) return ERROR(dstSize_tooSmall); + if (!srcSize) return ERROR(srcSize_wrong); + memset(oend - rleSize, *ip, rleSize); + *litStart = oend - rleSize; + *litSize = rleSize; + ip++; + break; + } + case bt_compressed: + { + size_t decodedLitSize = ZSTD_decompressLiterals(ctx, dst, maxDstSize, ip, litcSize); + if (ZSTDv01_isError(decodedLitSize)) return decodedLitSize; + *litStart = oend - decodedLitSize; + *litSize = decodedLitSize; + ip += litcSize; + break; + } + case bt_end: + default: + return ERROR(GENERIC); + } + + return ip-istart; +} + + +static size_t ZSTDv01_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr, + FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, + const void* src, size_t srcSize) +{ + const BYTE* const istart = (const BYTE* const)src; + const BYTE* ip = istart; + const BYTE* const iend = istart + srcSize; + U32 LLtype, Offtype, MLtype; + U32 LLlog, Offlog, MLlog; + size_t dumpsLength; + + /* check */ + if (srcSize < 5) return ERROR(srcSize_wrong); + + /* SeqHead */ + *nbSeq = ZSTD_readLE16(ip); ip+=2; + LLtype = *ip >> 6; + Offtype = (*ip >> 4) & 3; + MLtype = (*ip >> 2) & 3; + if (*ip & 2) + { + dumpsLength = ip[2]; + dumpsLength += ip[1] << 8; + ip += 3; + } + else + { + dumpsLength = ip[1]; + dumpsLength += (ip[0] & 1) << 8; + ip += 2; + } + *dumpsPtr = ip; + ip += dumpsLength; + *dumpsLengthPtr = dumpsLength; + + /* check */ + if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */ + + /* sequences */ + { + S16 norm[MaxML+1]; /* assumption : MaxML >= MaxLL and MaxOff */ + size_t headerSize; + + /* Build DTables */ + switch(LLtype) + { + case bt_rle : + LLlog = 0; + FSE_buildDTable_rle(DTableLL, *ip++); break; + case bt_raw : + LLlog = LLbits; + FSE_buildDTable_raw(DTableLL, LLbits); break; + default : + { U32 max = MaxLL; + headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip); + if (FSE_isError(headerSize)) return ERROR(GENERIC); + if (LLlog > LLFSELog) return ERROR(corruption_detected); + ip += headerSize; + FSE_buildDTable(DTableLL, norm, max, LLlog); + } } + + switch(Offtype) + { + case bt_rle : + Offlog = 0; + if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ + FSE_buildDTable_rle(DTableOffb, *ip++); break; + case bt_raw : + Offlog = Offbits; + FSE_buildDTable_raw(DTableOffb, Offbits); break; + default : + { U32 max = MaxOff; + headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip); + if (FSE_isError(headerSize)) return ERROR(GENERIC); + if (Offlog > OffFSELog) return ERROR(corruption_detected); + ip += headerSize; + FSE_buildDTable(DTableOffb, norm, max, Offlog); + } } + + switch(MLtype) + { + case bt_rle : + MLlog = 0; + if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ + FSE_buildDTable_rle(DTableML, *ip++); break; + case bt_raw : + MLlog = MLbits; + FSE_buildDTable_raw(DTableML, MLbits); break; + default : + { U32 max = MaxML; + headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip); + if (FSE_isError(headerSize)) return ERROR(GENERIC); + if (MLlog > MLFSELog) return ERROR(corruption_detected); + ip += headerSize; + FSE_buildDTable(DTableML, norm, max, MLlog); + } } } + + return ip-istart; +} + + +typedef struct { + size_t litLength; + size_t offset; + size_t matchLength; +} seq_t; + +typedef struct { + FSE_DStream_t DStream; + FSE_DState_t stateLL; + FSE_DState_t stateOffb; + FSE_DState_t stateML; + size_t prevOffset; + const BYTE* dumps; + const BYTE* dumpsEnd; +} seqState_t; + + +static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState) +{ + size_t litLength; + size_t prevOffset; + size_t offset; + size_t matchLength; + const BYTE* dumps = seqState->dumps; + const BYTE* const de = seqState->dumpsEnd; + + /* Literal length */ + litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream)); + prevOffset = litLength ? seq->offset : seqState->prevOffset; + seqState->prevOffset = seq->offset; + if (litLength == MaxLL) + { + U32 add = dumps<de ? *dumps++ : 0; + if (add < 255) litLength += add; + else + { + if (dumps<=(de-3)) + { + litLength = ZSTD_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */ + dumps += 3; + } + } + } + + /* Offset */ + { + U32 offsetCode, nbBits; + offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream)); + if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); + nbBits = offsetCode - 1; + if (offsetCode==0) nbBits = 0; /* cmove */ + offset = ((size_t)1 << (nbBits & ((sizeof(offset)*8)-1))) + FSE_readBits(&(seqState->DStream), nbBits); + if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); + if (offsetCode==0) offset = prevOffset; + } + + /* MatchLength */ + matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream)); + if (matchLength == MaxML) + { + U32 add = dumps<de ? *dumps++ : 0; + if (add < 255) matchLength += add; + else + { + if (dumps<=(de-3)) + { + matchLength = ZSTD_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */ + dumps += 3; + } + } + } + matchLength += MINMATCH; + + /* save result */ + seq->litLength = litLength; + seq->offset = offset; + seq->matchLength = matchLength; + seqState->dumps = dumps; +} + + +static size_t ZSTD_execSequence(BYTE* op, + seq_t sequence, + const BYTE** litPtr, const BYTE* const litLimit, + BYTE* const base, BYTE* const oend) +{ + static const int dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ + static const int dec64table[] = {8, 8, 8, 7, 8, 9,10,11}; /* subtracted */ + const BYTE* const ostart = op; + const size_t litLength = sequence.litLength; + BYTE* const endMatch = op + litLength + sequence.matchLength; /* risk : address space overflow (32-bits) */ + const BYTE* const litEnd = *litPtr + litLength; + + /* check */ + if (endMatch > oend) return ERROR(dstSize_tooSmall); /* overwrite beyond dst buffer */ + if (litEnd > litLimit) return ERROR(corruption_detected); + if (sequence.matchLength > (size_t)(*litPtr-op)) return ERROR(dstSize_tooSmall); /* overwrite literal segment */ + + /* copy Literals */ + if (((size_t)(*litPtr - op) < 8) || ((size_t)(oend-litEnd) < 8) || (op+litLength > oend-8)) + memmove(op, *litPtr, litLength); /* overwrite risk */ + else + ZSTD_wildcopy(op, *litPtr, litLength); + op += litLength; + *litPtr = litEnd; /* update for next sequence */ + + /* check : last match must be at a minimum distance of 8 from end of dest buffer */ + if (oend-op < 8) return ERROR(dstSize_tooSmall); + + /* copy Match */ + { + const U32 overlapRisk = (((size_t)(litEnd - endMatch)) < 12); + const BYTE* match = op - sequence.offset; /* possible underflow at op - offset ? */ + size_t qutt = 12; + U64 saved[2]; + + /* check */ + if (match < base) return ERROR(corruption_detected); + if (sequence.offset > (size_t)base) return ERROR(corruption_detected); + + /* save beginning of literal sequence, in case of write overlap */ + if (overlapRisk) + { + if ((endMatch + qutt) > oend) qutt = oend-endMatch; + memcpy(saved, endMatch, qutt); + } + + if (sequence.offset < 8) + { + const int dec64 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op+4, match); + match -= dec64; + } else { ZSTD_copy8(op, match); } + op += 8; match += 8; + + if (endMatch > oend-(16-MINMATCH)) + { + if (op < oend-8) + { + ZSTD_wildcopy(op, match, (oend-8) - op); + match += (oend-8) - op; + op = oend-8; + } + while (op<endMatch) *op++ = *match++; + } + else + ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */ + + /* restore, in case of overlap */ + if (overlapRisk) memcpy(endMatch, saved, qutt); + } + + return endMatch-ostart; +} + +typedef struct ZSTDv01_Dctx_s +{ + U32 LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; + U32 OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; + U32 MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; + void* previousDstEnd; + void* base; + size_t expected; + blockType_t bType; + U32 phase; +} dctx_t; + + +static size_t ZSTD_decompressSequences( + void* ctx, + void* dst, size_t maxDstSize, + const void* seqStart, size_t seqSize, + const BYTE* litStart, size_t litSize) +{ + dctx_t* dctx = (dctx_t*)ctx; + const BYTE* ip = (const BYTE*)seqStart; + const BYTE* const iend = ip + seqSize; + BYTE* const ostart = (BYTE* const)dst; + BYTE* op = ostart; + BYTE* const oend = ostart + maxDstSize; + size_t errorCode, dumpsLength; + const BYTE* litPtr = litStart; + const BYTE* const litEnd = litStart + litSize; + int nbSeq; + const BYTE* dumps; + U32* DTableLL = dctx->LLTable; + U32* DTableML = dctx->MLTable; + U32* DTableOffb = dctx->OffTable; + BYTE* const base = (BYTE*) (dctx->base); + + /* Build Decoding Tables */ + errorCode = ZSTDv01_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength, + DTableLL, DTableML, DTableOffb, + ip, iend-ip); + if (ZSTDv01_isError(errorCode)) return errorCode; + ip += errorCode; + + /* Regen sequences */ + { + seq_t sequence; + seqState_t seqState; + + memset(&sequence, 0, sizeof(sequence)); + seqState.dumps = dumps; + seqState.dumpsEnd = dumps + dumpsLength; + seqState.prevOffset = 1; + errorCode = FSE_initDStream(&(seqState.DStream), ip, iend-ip); + if (FSE_isError(errorCode)) return ERROR(corruption_detected); + FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL); + FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb); + FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML); + + for ( ; (FSE_reloadDStream(&(seqState.DStream)) <= FSE_DStream_completed) && (nbSeq>0) ; ) + { + size_t oneSeqSize; + nbSeq--; + ZSTD_decodeSequence(&sequence, &seqState); + oneSeqSize = ZSTD_execSequence(op, sequence, &litPtr, litEnd, base, oend); + if (ZSTDv01_isError(oneSeqSize)) return oneSeqSize; + op += oneSeqSize; + } + + /* check if reached exact end */ + if ( !FSE_endOfDStream(&(seqState.DStream)) ) return ERROR(corruption_detected); /* requested too much : data is corrupted */ + if (nbSeq<0) return ERROR(corruption_detected); /* requested too many sequences : data is corrupted */ + + /* last literal segment */ + { + size_t lastLLSize = litEnd - litPtr; + if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall); + if (op != litPtr) memmove(op, litPtr, lastLLSize); + op += lastLLSize; + } + } + + return op-ostart; +} + + +static size_t ZSTD_decompressBlock( + void* ctx, + void* dst, size_t maxDstSize, + const void* src, size_t srcSize) +{ + /* blockType == blockCompressed, srcSize is trusted */ + const BYTE* ip = (const BYTE*)src; + const BYTE* litPtr = NULL; + size_t litSize = 0; + size_t errorCode; + + /* Decode literals sub-block */ + errorCode = ZSTDv01_decodeLiteralsBlock(ctx, dst, maxDstSize, &litPtr, &litSize, src, srcSize); + if (ZSTDv01_isError(errorCode)) return errorCode; + ip += errorCode; + srcSize -= errorCode; + + return ZSTD_decompressSequences(ctx, dst, maxDstSize, ip, srcSize, litPtr, litSize); +} + + +size_t ZSTDv01_decompressDCtx(void* ctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) +{ + const BYTE* ip = (const BYTE*)src; + const BYTE* iend = ip + srcSize; + BYTE* const ostart = (BYTE* const)dst; + BYTE* op = ostart; + BYTE* const oend = ostart + maxDstSize; + size_t remainingSize = srcSize; + U32 magicNumber; + size_t errorCode=0; + blockProperties_t blockProperties; + + /* Frame Header */ + if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); + magicNumber = ZSTD_readBE32(src); + if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); + ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; + + /* Loop on each block */ + while (1) + { + size_t blockSize = ZSTDv01_getcBlockSize(ip, iend-ip, &blockProperties); + if (ZSTDv01_isError(blockSize)) return blockSize; + + ip += ZSTD_blockHeaderSize; + remainingSize -= ZSTD_blockHeaderSize; + if (blockSize > remainingSize) return ERROR(srcSize_wrong); + + switch(blockProperties.blockType) + { + case bt_compressed: + errorCode = ZSTD_decompressBlock(ctx, op, oend-op, ip, blockSize); + break; + case bt_raw : + errorCode = ZSTD_copyUncompressedBlock(op, oend-op, ip, blockSize); + break; + case bt_rle : + return ERROR(GENERIC); /* not yet supported */ + break; + case bt_end : + /* end of frame */ + if (remainingSize) return ERROR(srcSize_wrong); + break; + default: + return ERROR(GENERIC); + } + if (blockSize == 0) break; /* bt_end */ + + if (ZSTDv01_isError(errorCode)) return errorCode; + op += errorCode; + ip += blockSize; + remainingSize -= blockSize; + } + + return op-ostart; +} + +size_t ZSTDv01_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize) +{ + dctx_t ctx; + ctx.base = dst; + return ZSTDv01_decompressDCtx(&ctx, dst, maxDstSize, src, srcSize); +} + +/* ZSTD_errorFrameSizeInfoLegacy() : + assumes `cSize` and `dBound` are _not_ NULL */ +static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret) +{ + *cSize = ret; + *dBound = ZSTD_CONTENTSIZE_ERROR; +} + +void ZSTDv01_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound) +{ + const BYTE* ip = (const BYTE*)src; + size_t remainingSize = srcSize; + size_t nbBlocks = 0; + U32 magicNumber; + blockProperties_t blockProperties; + + /* Frame Header */ + if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) { + ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); + return; + } + magicNumber = ZSTD_readBE32(src); + if (magicNumber != ZSTD_magicNumber) { + ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown)); + return; + } + ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; + + /* Loop on each block */ + while (1) + { + size_t blockSize = ZSTDv01_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTDv01_isError(blockSize)) { + ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, blockSize); + return; + } + + ip += ZSTD_blockHeaderSize; + remainingSize -= ZSTD_blockHeaderSize; + if (blockSize > remainingSize) { + ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); + return; + } + + if (blockSize == 0) break; /* bt_end */ + + ip += blockSize; + remainingSize -= blockSize; + nbBlocks++; + } + + *cSize = ip - (const BYTE*)src; + *dBound = nbBlocks * BLOCKSIZE; +} + +/******************************* +* Streaming Decompression API +*******************************/ + +size_t ZSTDv01_resetDCtx(ZSTDv01_Dctx* dctx) +{ + dctx->expected = ZSTD_frameHeaderSize; + dctx->phase = 0; + dctx->previousDstEnd = NULL; + dctx->base = NULL; + return 0; +} + +ZSTDv01_Dctx* ZSTDv01_createDCtx(void) +{ + ZSTDv01_Dctx* dctx = (ZSTDv01_Dctx*)malloc(sizeof(ZSTDv01_Dctx)); + if (dctx==NULL) return NULL; + ZSTDv01_resetDCtx(dctx); + return dctx; +} + +size_t ZSTDv01_freeDCtx(ZSTDv01_Dctx* dctx) +{ + free(dctx); + return 0; +} + +size_t ZSTDv01_nextSrcSizeToDecompress(ZSTDv01_Dctx* dctx) +{ + return ((dctx_t*)dctx)->expected; +} + +size_t ZSTDv01_decompressContinue(ZSTDv01_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) +{ + dctx_t* ctx = (dctx_t*)dctx; + + /* Sanity check */ + if (srcSize != ctx->expected) return ERROR(srcSize_wrong); + if (dst != ctx->previousDstEnd) /* not contiguous */ + ctx->base = dst; + + /* Decompress : frame header */ + if (ctx->phase == 0) + { + /* Check frame magic header */ + U32 magicNumber = ZSTD_readBE32(src); + if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); + ctx->phase = 1; + ctx->expected = ZSTD_blockHeaderSize; + return 0; + } + + /* Decompress : block header */ + if (ctx->phase == 1) + { + blockProperties_t bp; + size_t blockSize = ZSTDv01_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); + if (ZSTDv01_isError(blockSize)) return blockSize; + if (bp.blockType == bt_end) + { + ctx->expected = 0; + ctx->phase = 0; + } + else + { + ctx->expected = blockSize; + ctx->bType = bp.blockType; + ctx->phase = 2; + } + + return 0; + } + + /* Decompress : block content */ + { + size_t rSize; + switch(ctx->bType) + { + case bt_compressed: + rSize = ZSTD_decompressBlock(ctx, dst, maxDstSize, src, srcSize); + break; + case bt_raw : + rSize = ZSTD_copyUncompressedBlock(dst, maxDstSize, src, srcSize); + break; + case bt_rle : + return ERROR(GENERIC); /* not yet handled */ + break; + case bt_end : /* should never happen (filtered at phase 1) */ + rSize = 0; + break; + default: + return ERROR(GENERIC); + } + ctx->phase = 1; + ctx->expected = ZSTD_blockHeaderSize; + ctx->previousDstEnd = (void*)( ((char*)dst) + rSize); + return rSize; + } + +} |