diff --git a/CHANGELOG.md b/CHANGELOG.md --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1,5 +1,10 @@ # Revision history for lz4-bytes +## 0.2.0.0 -- 2025-07-07 + +* Make it possible to compress much larger buffers as a frame +* Correctly handle frames with multiple blocks during decompression + ## 0.1.2.0 -- 2025-03-26 * Add `Lz4.Frame.decompressU`. diff --git a/cbits/hs_lz4.c b/cbits/hs_lz4.c --- a/cbits/hs_lz4.c +++ b/cbits/hs_lz4.c @@ -1,6 +1,8 @@ #include "Rts.h" #include "lz4.h" +#include "lz4frame.h" #include "lz4hc.h" +#include HsInt hs_compress_fast ( const char* src @@ -42,6 +44,103 @@ r = (HsInt)LZ4_decompress_safe(src + soff, dst + doff, slen, dstCapacity); return r; } + +// This implementation was copied adapted from the Python lz4.frame subpackage. +// This returns a zero on success. Here are the main changes made to the Python +// code: +// * This function is only called in contexts where the size of the decompressed +// data is communicated some other way, so we never need to grow the destination. +// * full_frame is removed because it is always true +// * This uses the unsafe FFI, so we can set stableDst to true unconditionally +// * We get rid of return_bytearray and return_bytes_read because we +// only return an indicator of whether or not the exact number of +// expected bytes were decompressed. +HsInt hs_decompress_frame(LZ4F_dctx * context, const char* const source, HsInt const source_off, HsInt const source_size, char* const destination, HsInt const decompressed_length) +{ + size_t source_remain = source_size; + size_t source_read; + const char * source_cursor; + const char * source_end; + char * destination_cursor; + size_t destination_written; + size_t result = 0; + LZ4F_frameInfo_t frame_info; + LZ4F_decompressOptions_t options = {0}; + int end_of_frame = 0; + size_t destination_write = decompressed_length; + + options.stableDst = 1; + options.skipChecksums = 1; + + source_cursor = source + source_off; + source_end = source + source_off + source_size; + source_remain = source_size; + source_read = source_size; + + result = LZ4F_getFrameInfo (context, &frame_info, source_cursor, &source_read); + if (LZ4F_isError (result)) { return result; } + + /* Advance the source_cursor pointer past the header - the call to + getFrameInfo above replaces the passed source_read value with the + number of bytes read. Also reduce source_remain accordingly. */ + source_cursor += source_read; + source_remain -= source_read; + + /* If the uncompressed content size is available, we'll use that to size + the destination buffer. Otherwise, guess at twice the remaining source + source as a starting point, and adjust if needed. */ + if (frame_info.contentSize > 0) + { + if (frame_info.contentSize != decompressed_length) { + return 20000; + } + } + + source_read = source_remain; + + destination_cursor = destination; + destination_written = 0; + + while (1) + { + /* Decompress from the source string and write to the destination + until there's no more source string to read, or until we've reached the + frame end. + + On calling LZ4F_decompress, source_read is set to the remaining length + of source available to read. On return, source_read is set to the + actual number of bytes read from source, which may be less than + available. NB: LZ4F_decompress does not explicitly fail on empty input. + + On calling LZ4F_decompress, destination_write is the number of bytes in + destination available for writing. On exit, destination_write is set to + the actual number of bytes written to destination. */ + result = LZ4F_decompress (context, destination_cursor, &destination_write, source_cursor, &source_read, &options); + + if (LZ4F_isError (result)) { return result; } + + destination_written += destination_write; + source_cursor += source_read; + source_read = source_end - source_cursor; + + if (result == 0) { + end_of_frame = 1; + break; + } + else if (source_cursor == source_end) { break; } + else if (destination_written == decompressed_length) { break; } + destination_cursor = destination + destination_written; + destination_write = decompressed_length - destination_written; + } + + if (result > 0) { return 20001; } + if (end_of_frame != 1) { return 20002; } + if (LZ4F_isError (result)) { return 20003; } + + return 0; +} + + // Started on streaming compression and then realized it has some // restrictions that make it pretty hard to wrap in Haskell. Read diff --git a/cbits/lz4.c b/cbits/lz4.c --- a/cbits/lz4.c +++ b/cbits/lz4.c @@ -1,2397 +1,2717 @@ /* LZ4 - Fast LZ compression algorithm - Copyright (C) 2011-present, Yann Collet. - - BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) - - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions are - met: - - * Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - * Redistributions in binary form must reproduce the above - copyright notice, this list of conditions and the following disclaimer - in the documentation and/or other materials provided with the - distribution. - - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - - You can contact the author at : - - LZ4 homepage : http://www.lz4.org - - LZ4 source repository : https://github.com/lz4/lz4 -*/ - -/*-************************************ -* Tuning parameters -**************************************/ -/* - * LZ4_HEAPMODE : - * Select how default compression functions will allocate memory for their hash table, - * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()). - */ -#ifndef LZ4_HEAPMODE -# define LZ4_HEAPMODE 0 -#endif - -/* - * ACCELERATION_DEFAULT : - * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0 - */ -#define ACCELERATION_DEFAULT 1 - - -/*-************************************ -* CPU Feature Detection -**************************************/ -/* LZ4_FORCE_MEMORY_ACCESS - * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. - * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. - * The below switch allow to select different access method for improved performance. - * Method 0 (default) : use `memcpy()`. Safe and portable. - * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). - * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. - * Method 2 : direct access. This method is portable but violate C standard. - * It can generate buggy code on targets which assembly generation depends on alignment. - * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) - * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. - * Prefer these methods in priority order (0 > 1 > 2) - */ -#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */ -# if defined(__GNUC__) && \ - ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) \ - || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) -# define LZ4_FORCE_MEMORY_ACCESS 2 -# elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__) -# define LZ4_FORCE_MEMORY_ACCESS 1 -# endif -#endif - -/* - * LZ4_FORCE_SW_BITCOUNT - * Define this parameter if your target system or compiler does not support hardware bit count - */ -#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */ -# define LZ4_FORCE_SW_BITCOUNT -#endif - - - -/*-************************************ -* Dependency -**************************************/ -/* - * LZ4_SRC_INCLUDED: - * Amalgamation flag, whether lz4.c is included - */ -#ifndef LZ4_SRC_INCLUDED -# define LZ4_SRC_INCLUDED 1 -#endif - -#ifndef LZ4_STATIC_LINKING_ONLY -#define LZ4_STATIC_LINKING_ONLY -#endif - -#ifndef LZ4_DISABLE_DEPRECATE_WARNINGS -#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */ -#endif - -#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */ -#include "lz4.h" -/* see also "memory routines" below */ - - -/*-************************************ -* Compiler Options -**************************************/ -#ifdef _MSC_VER /* Visual Studio */ -# include -# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ -# pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */ -#endif /* _MSC_VER */ - -#ifndef LZ4_FORCE_INLINE -# ifdef _MSC_VER /* Visual Studio */ -# define LZ4_FORCE_INLINE static __forceinline -# else -# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ -# ifdef __GNUC__ -# define LZ4_FORCE_INLINE static inline __attribute__((always_inline)) -# else -# define LZ4_FORCE_INLINE static inline -# endif -# else -# define LZ4_FORCE_INLINE static -# endif /* __STDC_VERSION__ */ -# endif /* _MSC_VER */ -#endif /* LZ4_FORCE_INLINE */ - -/* LZ4_FORCE_O2_GCC_PPC64LE and LZ4_FORCE_O2_INLINE_GCC_PPC64LE - * gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy8, - * together with a simple 8-byte copy loop as a fall-back path. - * However, this optimization hurts the decompression speed by >30%, - * because the execution does not go to the optimized loop - * for typical compressible data, and all of the preamble checks - * before going to the fall-back path become useless overhead. - * This optimization happens only with the -O3 flag, and -O2 generates - * a simple 8-byte copy loop. - * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy8 - * functions are annotated with __attribute__((optimize("O2"))), - * and also LZ4_wildCopy8 is forcibly inlined, so that the O2 attribute - * of LZ4_wildCopy8 does not affect the compression speed. - */ -#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__) && !defined(__clang__) -# define LZ4_FORCE_O2_GCC_PPC64LE __attribute__((optimize("O2"))) -# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE __attribute__((optimize("O2"))) LZ4_FORCE_INLINE -#else -# define LZ4_FORCE_O2_GCC_PPC64LE -# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE static -#endif - -#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__) -# define expect(expr,value) (__builtin_expect ((expr),(value)) ) -#else -# define expect(expr,value) (expr) -#endif - -#ifndef likely -#define likely(expr) expect((expr) != 0, 1) -#endif -#ifndef unlikely -#define unlikely(expr) expect((expr) != 0, 0) -#endif - - -/*-************************************ -* Memory routines -**************************************/ -#include /* malloc, calloc, free */ -#define ALLOC(s) malloc(s) -#define ALLOC_AND_ZERO(s) calloc(1,s) -#define FREEMEM(p) free(p) -#include /* memset, memcpy */ -#define MEM_INIT(p,v,s) memset((p),(v),(s)) - - -/*-************************************ -* Common Constants -**************************************/ -#define MINMATCH 4 - -#define WILDCOPYLENGTH 8 -#define LASTLITERALS 5 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ -#define MFLIMIT 12 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ -#define MATCH_SAFEGUARD_DISTANCE ((2*WILDCOPYLENGTH) - MINMATCH) /* ensure it's possible to write 2 x wildcopyLength without overflowing output buffer */ -#define FASTLOOP_SAFE_DISTANCE 64 -static const int LZ4_minLength = (MFLIMIT+1); - -#define KB *(1 <<10) -#define MB *(1 <<20) -#define GB *(1U<<30) - -#define LZ4_DISTANCE_ABSOLUTE_MAX 65535 -#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */ -# error "LZ4_DISTANCE_MAX is too big : must be <= 65535" -#endif - -#define ML_BITS 4 -#define ML_MASK ((1U<=1) -# include -#else -# ifndef assert -# define assert(condition) ((void)0) -# endif -#endif - -#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use after variable declarations */ - -#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2) -# include - static int g_debuglog_enable = 1; -# define DEBUGLOG(l, ...) { \ - if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \ - fprintf(stderr, __FILE__ ": "); \ - fprintf(stderr, __VA_ARGS__); \ - fprintf(stderr, " \n"); \ - } } -#else -# define DEBUGLOG(l, ...) {} /* disabled */ -#endif - - -/*-************************************ -* Types -**************************************/ -#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) -# include - typedef uint8_t BYTE; - typedef uint16_t U16; - typedef uint32_t U32; - typedef int32_t S32; - typedef uint64_t U64; - typedef uintptr_t uptrval; -#else -# include -# if UINT_MAX != 4294967295UL -# error "LZ4 code (when not C++ or C99) assumes that sizeof(int) == 4" -# endif - typedef unsigned char BYTE; - typedef unsigned short U16; - typedef unsigned int U32; - typedef signed int S32; - typedef unsigned long long U64; - typedef size_t uptrval; /* generally true, except OpenVMS-64 */ -#endif - -#if defined(__x86_64__) - typedef U64 reg_t; /* 64-bits in x32 mode */ -#else - typedef size_t reg_t; /* 32-bits in x32 mode */ -#endif - -typedef enum { - notLimited = 0, - limitedOutput = 1, - fillOutput = 2 -} limitedOutput_directive; - - -/*-************************************ -* Reading and writing into memory -**************************************/ -static unsigned LZ4_isLittleEndian(void) -{ - const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ - return one.c[0]; -} - - -#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2) -/* lie to the compiler about data alignment; use with caution */ - -static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; } -static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; } -static reg_t LZ4_read_ARCH(const void* memPtr) { return *(const reg_t*) memPtr; } - -static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; } -static void LZ4_write32(void* memPtr, U32 value) { *(U32*)memPtr = value; } - -#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1) - -/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ -/* currently only defined for gcc and icc */ -typedef union { U16 u16; U32 u32; reg_t uArch; } __attribute__((packed)) unalign; - -static U16 LZ4_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } -static U32 LZ4_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } -static reg_t LZ4_read_ARCH(const void* ptr) { return ((const unalign*)ptr)->uArch; } - -static void LZ4_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; } -static void LZ4_write32(void* memPtr, U32 value) { ((unalign*)memPtr)->u32 = value; } - -#else /* safe and portable access using memcpy() */ - -static U16 LZ4_read16(const void* memPtr) -{ - U16 val; memcpy(&val, memPtr, sizeof(val)); return val; -} - -static U32 LZ4_read32(const void* memPtr) -{ - U32 val; memcpy(&val, memPtr, sizeof(val)); return val; -} - -static reg_t LZ4_read_ARCH(const void* memPtr) -{ - reg_t val; memcpy(&val, memPtr, sizeof(val)); return val; -} - -static void LZ4_write16(void* memPtr, U16 value) -{ - memcpy(memPtr, &value, sizeof(value)); -} - -static void LZ4_write32(void* memPtr, U32 value) -{ - memcpy(memPtr, &value, sizeof(value)); -} - -#endif /* LZ4_FORCE_MEMORY_ACCESS */ - - -static U16 LZ4_readLE16(const void* memPtr) -{ - if (LZ4_isLittleEndian()) { - return LZ4_read16(memPtr); - } else { - const BYTE* p = (const BYTE*)memPtr; - return (U16)((U16)p[0] + (p[1]<<8)); - } -} - -static void LZ4_writeLE16(void* memPtr, U16 value) -{ - if (LZ4_isLittleEndian()) { - LZ4_write16(memPtr, value); - } else { - BYTE* p = (BYTE*)memPtr; - p[0] = (BYTE) value; - p[1] = (BYTE)(value>>8); - } -} - -/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */ -LZ4_FORCE_O2_INLINE_GCC_PPC64LE -void LZ4_wildCopy8(void* dstPtr, const void* srcPtr, void* dstEnd) -{ - BYTE* d = (BYTE*)dstPtr; - const BYTE* s = (const BYTE*)srcPtr; - BYTE* const e = (BYTE*)dstEnd; - - do { memcpy(d,s,8); d+=8; s+=8; } while (d= 16. */ -LZ4_FORCE_O2_INLINE_GCC_PPC64LE void -LZ4_wildCopy32(void* dstPtr, const void* srcPtr, void* dstEnd) -{ - BYTE* d = (BYTE*)dstPtr; - const BYTE* s = (const BYTE*)srcPtr; - BYTE* const e = (BYTE*)dstEnd; - - do { memcpy(d,s,16); memcpy(d+16,s+16,16); d+=32; s+=32; } while (d= dstPtr + MINMATCH - * - there is at least 8 bytes available to write after dstEnd */ -LZ4_FORCE_O2_INLINE_GCC_PPC64LE void -LZ4_memcpy_using_offset(BYTE* dstPtr, const BYTE* srcPtr, BYTE* dstEnd, const size_t offset) -{ - BYTE v[8]; - - assert(dstEnd >= dstPtr + MINMATCH); - LZ4_write32(dstPtr, 0); /* silence an msan warning when offset==0 */ - - switch(offset) { - case 1: - memset(v, *srcPtr, 8); - break; - case 2: - memcpy(v, srcPtr, 2); - memcpy(&v[2], srcPtr, 2); - memcpy(&v[4], &v[0], 4); - break; - case 4: - memcpy(v, srcPtr, 4); - memcpy(&v[4], srcPtr, 4); - break; - default: - LZ4_memcpy_using_offset_base(dstPtr, srcPtr, dstEnd, offset); - return; - } - - memcpy(dstPtr, v, 8); - dstPtr += 8; - while (dstPtr < dstEnd) { - memcpy(dstPtr, v, 8); - dstPtr += 8; - } -} -#endif - - -/*-************************************ -* Common functions -**************************************/ -static unsigned LZ4_NbCommonBytes (reg_t val) -{ - if (LZ4_isLittleEndian()) { - if (sizeof(val)==8) { -# if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) - unsigned long r = 0; - _BitScanForward64( &r, (U64)val ); - return (int)(r>>3); -# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT) - return (unsigned)__builtin_ctzll((U64)val) >> 3; -# else - static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, - 0, 3, 1, 3, 1, 4, 2, 7, - 0, 2, 3, 6, 1, 5, 3, 5, - 1, 3, 4, 4, 2, 5, 6, 7, - 7, 0, 1, 2, 3, 3, 4, 6, - 2, 6, 5, 5, 3, 4, 5, 6, - 7, 1, 2, 4, 6, 4, 4, 5, - 7, 2, 6, 5, 7, 6, 7, 7 }; - return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58]; -# endif - } else /* 32 bits */ { -# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) - unsigned long r; - _BitScanForward( &r, (U32)val ); - return (int)(r>>3); -# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT) - return (unsigned)__builtin_ctz((U32)val) >> 3; -# else - static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, - 3, 2, 2, 1, 3, 2, 0, 1, - 3, 3, 1, 2, 2, 2, 2, 0, - 3, 1, 2, 0, 1, 0, 1, 1 }; - return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27]; -# endif - } - } else /* Big Endian CPU */ { - if (sizeof(val)==8) { /* 64-bits */ -# if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) - unsigned long r = 0; - _BitScanReverse64( &r, val ); - return (unsigned)(r>>3); -# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT) - return (unsigned)__builtin_clzll((U64)val) >> 3; -# else - static const U32 by32 = sizeof(val)*4; /* 32 on 64 bits (goal), 16 on 32 bits. - Just to avoid some static analyzer complaining about shift by 32 on 32-bits target. - Note that this code path is never triggered in 32-bits mode. */ - unsigned r; - if (!(val>>by32)) { r=4; } else { r=0; val>>=by32; } - if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; } - r += (!val); - return r; -# endif - } else /* 32 bits */ { -# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) - unsigned long r = 0; - _BitScanReverse( &r, (unsigned long)val ); - return (unsigned)(r>>3); -# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT) - return (unsigned)__builtin_clz((U32)val) >> 3; -# else - unsigned r; - if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; } - r += (!val); - return r; -# endif - } - } -} - -#define STEPSIZE sizeof(reg_t) -LZ4_FORCE_INLINE -unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit) -{ - const BYTE* const pStart = pIn; - - if (likely(pIn < pInLimit-(STEPSIZE-1))) { - reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); - if (!diff) { - pIn+=STEPSIZE; pMatch+=STEPSIZE; - } else { - return LZ4_NbCommonBytes(diff); - } } - - while (likely(pIn < pInLimit-(STEPSIZE-1))) { - reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); - if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; } - pIn += LZ4_NbCommonBytes(diff); - return (unsigned)(pIn - pStart); - } - - if ((STEPSIZE==8) && (pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; } - if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; } - if ((pIn compression run slower on incompressible data */ - - -/*-************************************ -* Local Structures and types -**************************************/ -typedef enum { clearedTable = 0, byPtr, byU32, byU16 } tableType_t; - -/** - * This enum distinguishes several different modes of accessing previous - * content in the stream. - * - * - noDict : There is no preceding content. - * - withPrefix64k : Table entries up to ctx->dictSize before the current blob - * blob being compressed are valid and refer to the preceding - * content (of length ctx->dictSize), which is available - * contiguously preceding in memory the content currently - * being compressed. - * - usingExtDict : Like withPrefix64k, but the preceding content is somewhere - * else in memory, starting at ctx->dictionary with length - * ctx->dictSize. - * - usingDictCtx : Like usingExtDict, but everything concerning the preceding - * content is in a separate context, pointed to by - * ctx->dictCtx. ctx->dictionary, ctx->dictSize, and table - * entries in the current context that refer to positions - * preceding the beginning of the current compression are - * ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx - * ->dictSize describe the location and size of the preceding - * content, and matches are found by looking in the ctx - * ->dictCtx->hashTable. - */ -typedef enum { noDict = 0, withPrefix64k, usingExtDict, usingDictCtx } dict_directive; -typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive; - - -/*-************************************ -* Local Utils -**************************************/ -int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; } -const char* LZ4_versionString(void) { return LZ4_VERSION_STRING; } -int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); } -int LZ4_sizeofState() { return LZ4_STREAMSIZE; } - - -/*-************************************ -* Internal Definitions used in Tests -**************************************/ -#if defined (__cplusplus) -extern "C" { -#endif - -int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize); - -int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, - int compressedSize, int maxOutputSize, - const void* dictStart, size_t dictSize); - -#if defined (__cplusplus) -} -#endif - -/*-****************************** -* Compression functions -********************************/ -static U32 LZ4_hash4(U32 sequence, tableType_t const tableType) -{ - if (tableType == byU16) - return ((sequence * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1))); - else - return ((sequence * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG)); -} - -static U32 LZ4_hash5(U64 sequence, tableType_t const tableType) -{ - const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG; - if (LZ4_isLittleEndian()) { - const U64 prime5bytes = 889523592379ULL; - return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog)); - } else { - const U64 prime8bytes = 11400714785074694791ULL; - return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog)); - } -} - -LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType) -{ - if ((sizeof(reg_t)==8) && (tableType != byU16)) return LZ4_hash5(LZ4_read_ARCH(p), tableType); - return LZ4_hash4(LZ4_read32(p), tableType); -} - -static void LZ4_clearHash(U32 h, void* tableBase, tableType_t const tableType) -{ - switch (tableType) - { - default: /* fallthrough */ - case clearedTable: { /* illegal! */ assert(0); return; } - case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = NULL; return; } - case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = 0; return; } - case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = 0; return; } - } -} - -static void LZ4_putIndexOnHash(U32 idx, U32 h, void* tableBase, tableType_t const tableType) -{ - switch (tableType) - { - default: /* fallthrough */ - case clearedTable: /* fallthrough */ - case byPtr: { /* illegal! */ assert(0); return; } - case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = idx; return; } - case byU16: { U16* hashTable = (U16*) tableBase; assert(idx < 65536); hashTable[h] = (U16)idx; return; } - } -} - -static void LZ4_putPositionOnHash(const BYTE* p, U32 h, - void* tableBase, tableType_t const tableType, - const BYTE* srcBase) -{ - switch (tableType) - { - case clearedTable: { /* illegal! */ assert(0); return; } - case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; } - case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; } - case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; } - } -} - -LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) -{ - U32 const h = LZ4_hashPosition(p, tableType); - LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase); -} - -/* LZ4_getIndexOnHash() : - * Index of match position registered in hash table. - * hash position must be calculated by using base+index, or dictBase+index. - * Assumption 1 : only valid if tableType == byU32 or byU16. - * Assumption 2 : h is presumed valid (within limits of hash table) - */ -static U32 LZ4_getIndexOnHash(U32 h, const void* tableBase, tableType_t tableType) -{ - LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2); - if (tableType == byU32) { - const U32* const hashTable = (const U32*) tableBase; - assert(h < (1U << (LZ4_MEMORY_USAGE-2))); - return hashTable[h]; - } - if (tableType == byU16) { - const U16* const hashTable = (const U16*) tableBase; - assert(h < (1U << (LZ4_MEMORY_USAGE-1))); - return hashTable[h]; - } - assert(0); return 0; /* forbidden case */ -} - -static const BYTE* LZ4_getPositionOnHash(U32 h, const void* tableBase, tableType_t tableType, const BYTE* srcBase) -{ - if (tableType == byPtr) { const BYTE* const* hashTable = (const BYTE* const*) tableBase; return hashTable[h]; } - if (tableType == byU32) { const U32* const hashTable = (const U32*) tableBase; return hashTable[h] + srcBase; } - { const U16* const hashTable = (const U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */ -} - -LZ4_FORCE_INLINE const BYTE* -LZ4_getPosition(const BYTE* p, - const void* tableBase, tableType_t tableType, - const BYTE* srcBase) -{ - U32 const h = LZ4_hashPosition(p, tableType); - return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase); -} - -LZ4_FORCE_INLINE void -LZ4_prepareTable(LZ4_stream_t_internal* const cctx, - const int inputSize, - const tableType_t tableType) { - /* If compression failed during the previous step, then the context - * is marked as dirty, therefore, it has to be fully reset. - */ - if (cctx->dirty) { - DEBUGLOG(5, "LZ4_prepareTable: Full reset for %p", cctx); - MEM_INIT(cctx, 0, sizeof(LZ4_stream_t_internal)); - return; - } - - /* If the table hasn't been used, it's guaranteed to be zeroed out, and is - * therefore safe to use no matter what mode we're in. Otherwise, we figure - * out if it's safe to leave as is or whether it needs to be reset. - */ - if (cctx->tableType != clearedTable) { - assert(inputSize >= 0); - if (cctx->tableType != tableType - || ((tableType == byU16) && cctx->currentOffset + (unsigned)inputSize >= 0xFFFFU) - || ((tableType == byU32) && cctx->currentOffset > 1 GB) - || tableType == byPtr - || inputSize >= 4 KB) - { - DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx); - MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE); - cctx->currentOffset = 0; - cctx->tableType = clearedTable; - } else { - DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)"); - } - } - - /* Adding a gap, so all previous entries are > LZ4_DISTANCE_MAX back, is faster - * than compressing without a gap. However, compressing with - * currentOffset == 0 is faster still, so we preserve that case. - */ - if (cctx->currentOffset != 0 && tableType == byU32) { - DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset"); - cctx->currentOffset += 64 KB; - } - - /* Finally, clear history */ - cctx->dictCtx = NULL; - cctx->dictionary = NULL; - cctx->dictSize = 0; -} - -/** LZ4_compress_generic() : - inlined, to ensure branches are decided at compilation time */ -LZ4_FORCE_INLINE int LZ4_compress_generic( - LZ4_stream_t_internal* const cctx, - const char* const source, - char* const dest, - const int inputSize, - int *inputConsumed, /* only written when outputDirective == fillOutput */ - const int maxOutputSize, - const limitedOutput_directive outputDirective, - const tableType_t tableType, - const dict_directive dictDirective, - const dictIssue_directive dictIssue, - const int acceleration) -{ - int result; - const BYTE* ip = (const BYTE*) source; - - U32 const startIndex = cctx->currentOffset; - const BYTE* base = (const BYTE*) source - startIndex; - const BYTE* lowLimit; - - const LZ4_stream_t_internal* dictCtx = (const LZ4_stream_t_internal*) cctx->dictCtx; - const BYTE* const dictionary = - dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary; - const U32 dictSize = - dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize; - const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */ - - int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx); - U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */ - const BYTE* const dictEnd = dictionary + dictSize; - const BYTE* anchor = (const BYTE*) source; - const BYTE* const iend = ip + inputSize; - const BYTE* const mflimitPlusOne = iend - MFLIMIT + 1; - const BYTE* const matchlimit = iend - LASTLITERALS; - - /* the dictCtx currentOffset is indexed on the start of the dictionary, - * while a dictionary in the current context precedes the currentOffset */ - const BYTE* dictBase = (dictDirective == usingDictCtx) ? - dictionary + dictSize - dictCtx->currentOffset : - dictionary + dictSize - startIndex; - - BYTE* op = (BYTE*) dest; - BYTE* const olimit = op + maxOutputSize; - - U32 offset = 0; - U32 forwardH; - - DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, tableType=%u", inputSize, tableType); - /* If init conditions are not met, we don't have to mark stream - * as having dirty context, since no action was taken yet */ - if (outputDirective == fillOutput && maxOutputSize < 1) { return 0; } /* Impossible to store anything */ - if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) { return 0; } /* Unsupported inputSize, too large (or negative) */ - if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) { return 0; } /* Size too large (not within 64K limit) */ - if (tableType==byPtr) assert(dictDirective==noDict); /* only supported use case with byPtr */ - assert(acceleration >= 1); - - lowLimit = (const BYTE*)source - (dictDirective == withPrefix64k ? dictSize : 0); - - /* Update context state */ - if (dictDirective == usingDictCtx) { - /* Subsequent linked blocks can't use the dictionary. */ - /* Instead, they use the block we just compressed. */ - cctx->dictCtx = NULL; - cctx->dictSize = (U32)inputSize; - } else { - cctx->dictSize += (U32)inputSize; - } - cctx->currentOffset += (U32)inputSize; - cctx->tableType = (U16)tableType; - - if (inputSizehashTable, tableType, base); - ip++; forwardH = LZ4_hashPosition(ip, tableType); - - /* Main Loop */ - for ( ; ; ) { - const BYTE* match; - BYTE* token; - const BYTE* filledIp; - - /* Find a match */ - if (tableType == byPtr) { - const BYTE* forwardIp = ip; - int step = 1; - int searchMatchNb = acceleration << LZ4_skipTrigger; - do { - U32 const h = forwardH; - ip = forwardIp; - forwardIp += step; - step = (searchMatchNb++ >> LZ4_skipTrigger); - - if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; - assert(ip < mflimitPlusOne); - - match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base); - forwardH = LZ4_hashPosition(forwardIp, tableType); - LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base); - - } while ( (match+LZ4_DISTANCE_MAX < ip) - || (LZ4_read32(match) != LZ4_read32(ip)) ); - - } else { /* byU32, byU16 */ - - const BYTE* forwardIp = ip; - int step = 1; - int searchMatchNb = acceleration << LZ4_skipTrigger; - do { - U32 const h = forwardH; - U32 const current = (U32)(forwardIp - base); - U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); - assert(matchIndex <= current); - assert(forwardIp - base < (ptrdiff_t)(2 GB - 1)); - ip = forwardIp; - forwardIp += step; - step = (searchMatchNb++ >> LZ4_skipTrigger); - - if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; - assert(ip < mflimitPlusOne); - - if (dictDirective == usingDictCtx) { - if (matchIndex < startIndex) { - /* there was no match, try the dictionary */ - assert(tableType == byU32); - matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); - match = dictBase + matchIndex; - matchIndex += dictDelta; /* make dictCtx index comparable with current context */ - lowLimit = dictionary; - } else { - match = base + matchIndex; - lowLimit = (const BYTE*)source; - } - } else if (dictDirective==usingExtDict) { - if (matchIndex < startIndex) { - DEBUGLOG(7, "extDict candidate: matchIndex=%5u < startIndex=%5u", matchIndex, startIndex); - assert(startIndex - matchIndex >= MINMATCH); - match = dictBase + matchIndex; - lowLimit = dictionary; - } else { - match = base + matchIndex; - lowLimit = (const BYTE*)source; - } - } else { /* single continuous memory segment */ - match = base + matchIndex; - } - forwardH = LZ4_hashPosition(forwardIp, tableType); - LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); - - DEBUGLOG(7, "candidate at pos=%u (offset=%u \n", matchIndex, current - matchIndex); - if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) { continue; } /* match outside of valid area */ - assert(matchIndex < current); - if ( ((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX)) - && (matchIndex+LZ4_DISTANCE_MAX < current)) { - continue; - } /* too far */ - assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */ - - if (LZ4_read32(match) == LZ4_read32(ip)) { - if (maybe_extMem) offset = current - matchIndex; - break; /* match found */ - } - - } while(1); - } - - /* Catch up */ - filledIp = ip; - while (((ip>anchor) & (match > lowLimit)) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; } - - /* Encode Literals */ - { unsigned const litLength = (unsigned)(ip - anchor); - token = op++; - if ((outputDirective == limitedOutput) && /* Check output buffer overflow */ - (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)) ) { - return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ - } - if ((outputDirective == fillOutput) && - (unlikely(op + (litLength+240)/255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))) { - op--; - goto _last_literals; - } - if (litLength >= RUN_MASK) { - int len = (int)(litLength - RUN_MASK); - *token = (RUN_MASK<= 255 ; len-=255) *op++ = 255; - *op++ = (BYTE)len; - } - else *token = (BYTE)(litLength< olimit)) { - /* the match was too close to the end, rewind and go to last literals */ - op = token; - goto _last_literals; - } - - /* Encode Offset */ - if (maybe_extMem) { /* static test */ - DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE*)source)); - assert(offset <= LZ4_DISTANCE_MAX && offset > 0); - LZ4_writeLE16(op, (U16)offset); op+=2; - } else { - DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match)); - assert(ip-match <= LZ4_DISTANCE_MAX); - LZ4_writeLE16(op, (U16)(ip - match)); op+=2; - } - - /* Encode MatchLength */ - { unsigned matchCode; - - if ( (dictDirective==usingExtDict || dictDirective==usingDictCtx) - && (lowLimit==dictionary) /* match within extDict */ ) { - const BYTE* limit = ip + (dictEnd-match); - assert(dictEnd > match); - if (limit > matchlimit) limit = matchlimit; - matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, limit); - ip += (size_t)matchCode + MINMATCH; - if (ip==limit) { - unsigned const more = LZ4_count(limit, (const BYTE*)source, matchlimit); - matchCode += more; - ip += more; - } - DEBUGLOG(6, " with matchLength=%u starting in extDict", matchCode+MINMATCH); - } else { - matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit); - ip += (size_t)matchCode + MINMATCH; - DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH); - } - - if ((outputDirective) && /* Check output buffer overflow */ - (unlikely(op + (1 + LASTLITERALS) + (matchCode+240)/255 > olimit)) ) { - if (outputDirective == fillOutput) { - /* Match description too long : reduce it */ - U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 1 - LASTLITERALS) * 255; - ip -= matchCode - newMatchCode; - assert(newMatchCode < matchCode); - matchCode = newMatchCode; - if (unlikely(ip <= filledIp)) { - /* We have already filled up to filledIp so if ip ends up less than filledIp - * we have positions in the hash table beyond the current position. This is - * a problem if we reuse the hash table. So we have to remove these positions - * from the hash table. - */ - const BYTE* ptr; - DEBUGLOG(5, "Clearing %u positions", (U32)(filledIp - ip)); - for (ptr = ip; ptr <= filledIp; ++ptr) { - U32 const h = LZ4_hashPosition(ptr, tableType); - LZ4_clearHash(h, cctx->hashTable, tableType); - } - } - } else { - assert(outputDirective == limitedOutput); - return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ - } - } - if (matchCode >= ML_MASK) { - *token += ML_MASK; - matchCode -= ML_MASK; - LZ4_write32(op, 0xFFFFFFFF); - while (matchCode >= 4*255) { - op+=4; - LZ4_write32(op, 0xFFFFFFFF); - matchCode -= 4*255; - } - op += matchCode / 255; - *op++ = (BYTE)(matchCode % 255); - } else - *token += (BYTE)(matchCode); - } - /* Ensure we have enough space for the last literals. */ - assert(!(outputDirective == fillOutput && op + 1 + LASTLITERALS > olimit)); - - anchor = ip; - - /* Test end of chunk */ - if (ip >= mflimitPlusOne) break; - - /* Fill table */ - LZ4_putPosition(ip-2, cctx->hashTable, tableType, base); - - /* Test next position */ - if (tableType == byPtr) { - - match = LZ4_getPosition(ip, cctx->hashTable, tableType, base); - LZ4_putPosition(ip, cctx->hashTable, tableType, base); - if ( (match+LZ4_DISTANCE_MAX >= ip) - && (LZ4_read32(match) == LZ4_read32(ip)) ) - { token=op++; *token=0; goto _next_match; } - - } else { /* byU32, byU16 */ - - U32 const h = LZ4_hashPosition(ip, tableType); - U32 const current = (U32)(ip-base); - U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); - assert(matchIndex < current); - if (dictDirective == usingDictCtx) { - if (matchIndex < startIndex) { - /* there was no match, try the dictionary */ - matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); - match = dictBase + matchIndex; - lowLimit = dictionary; /* required for match length counter */ - matchIndex += dictDelta; - } else { - match = base + matchIndex; - lowLimit = (const BYTE*)source; /* required for match length counter */ - } - } else if (dictDirective==usingExtDict) { - if (matchIndex < startIndex) { - match = dictBase + matchIndex; - lowLimit = dictionary; /* required for match length counter */ - } else { - match = base + matchIndex; - lowLimit = (const BYTE*)source; /* required for match length counter */ - } - } else { /* single memory segment */ - match = base + matchIndex; - } - LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); - assert(matchIndex < current); - if ( ((dictIssue==dictSmall) ? (matchIndex >= prefixIdxLimit) : 1) - && (((tableType==byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex+LZ4_DISTANCE_MAX >= current)) - && (LZ4_read32(match) == LZ4_read32(ip)) ) { - token=op++; - *token=0; - if (maybe_extMem) offset = current - matchIndex; - DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i", - (int)(anchor-(const BYTE*)source), 0, (int)(ip-(const BYTE*)source)); - goto _next_match; - } - } - - /* Prepare next loop */ - forwardH = LZ4_hashPosition(++ip, tableType); - - } - -_last_literals: - /* Encode Last Literals */ - { size_t lastRun = (size_t)(iend - anchor); - if ( (outputDirective) && /* Check output buffer overflow */ - (op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) { - if (outputDirective == fillOutput) { - /* adapt lastRun to fill 'dst' */ - assert(olimit >= op); - lastRun = (size_t)(olimit-op) - 1; - lastRun -= (lastRun+240)/255; - } else { - assert(outputDirective == limitedOutput); - return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ - } - } - if (lastRun >= RUN_MASK) { - size_t accumulator = lastRun - RUN_MASK; - *op++ = RUN_MASK << ML_BITS; - for(; accumulator >= 255 ; accumulator-=255) *op++ = 255; - *op++ = (BYTE) accumulator; - } else { - *op++ = (BYTE)(lastRun< 0); - return result; -} - - -int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) -{ - LZ4_stream_t_internal* const ctx = & LZ4_initStream(state, sizeof(LZ4_stream_t)) -> internal_donotuse; - assert(ctx != NULL); - if (acceleration < 1) acceleration = ACCELERATION_DEFAULT; - if (maxOutputSize >= LZ4_compressBound(inputSize)) { - if (inputSize < LZ4_64Klimit) { - return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration); - } else { - const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; - return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); - } - } else { - if (inputSize < LZ4_64Klimit) { - return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration); - } else { - const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; - return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration); - } - } -} - -/** - * LZ4_compress_fast_extState_fastReset() : - * A variant of LZ4_compress_fast_extState(). - * - * Using this variant avoids an expensive initialization step. It is only safe - * to call if the state buffer is known to be correctly initialized already - * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of - * "correctly initialized"). - */ -int LZ4_compress_fast_extState_fastReset(void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration) -{ - LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse; - if (acceleration < 1) acceleration = ACCELERATION_DEFAULT; - - if (dstCapacity >= LZ4_compressBound(srcSize)) { - if (srcSize < LZ4_64Klimit) { - const tableType_t tableType = byU16; - LZ4_prepareTable(ctx, srcSize, tableType); - if (ctx->currentOffset) { - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration); - } else { - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); - } - } else { - const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; - LZ4_prepareTable(ctx, srcSize, tableType); - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); - } - } else { - if (srcSize < LZ4_64Klimit) { - const tableType_t tableType = byU16; - LZ4_prepareTable(ctx, srcSize, tableType); - if (ctx->currentOffset) { - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration); - } else { - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); - } - } else { - const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; - LZ4_prepareTable(ctx, srcSize, tableType); - return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); - } - } -} - - -int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) -{ - int result; -#if (LZ4_HEAPMODE) - LZ4_stream_t* ctxPtr = ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ - if (ctxPtr == NULL) return 0; -#else - LZ4_stream_t ctx; - LZ4_stream_t* const ctxPtr = &ctx; -#endif - result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration); - -#if (LZ4_HEAPMODE) - FREEMEM(ctxPtr); -#endif - return result; -} - - -int LZ4_compress_default(const char* src, char* dst, int srcSize, int maxOutputSize) -{ - return LZ4_compress_fast(src, dst, srcSize, maxOutputSize, 1); -} - - -/* hidden debug function */ -/* strangely enough, gcc generates faster code when this function is uncommented, even if unused */ -int LZ4_compress_fast_force(const char* src, char* dst, int srcSize, int dstCapacity, int acceleration) -{ - LZ4_stream_t ctx; - LZ4_initStream(&ctx, sizeof(ctx)); - - if (srcSize < LZ4_64Klimit) { - return LZ4_compress_generic(&ctx.internal_donotuse, src, dst, srcSize, NULL, dstCapacity, limitedOutput, byU16, noDict, noDictIssue, acceleration); - } else { - tableType_t const addrMode = (sizeof(void*) > 4) ? byU32 : byPtr; - return LZ4_compress_generic(&ctx.internal_donotuse, src, dst, srcSize, NULL, dstCapacity, limitedOutput, addrMode, noDict, noDictIssue, acceleration); - } -} - - -/* Note!: This function leaves the stream in an unclean/broken state! - * It is not safe to subsequently use the same state with a _fastReset() or - * _continue() call without resetting it. */ -static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize) -{ - void* const s = LZ4_initStream(state, sizeof (*state)); - assert(s != NULL); (void)s; - - if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) { /* compression success is guaranteed */ - return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1); - } else { - if (*srcSizePtr < LZ4_64Klimit) { - return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1); - } else { - tableType_t const addrMode = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; - return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, addrMode, noDict, noDictIssue, 1); - } } -} - - -int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize) -{ -#if (LZ4_HEAPMODE) - LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ - if (ctx == NULL) return 0; -#else - LZ4_stream_t ctxBody; - LZ4_stream_t* ctx = &ctxBody; -#endif - - int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize); - -#if (LZ4_HEAPMODE) - FREEMEM(ctx); -#endif - return result; -} - - - -/*-****************************** -* Streaming functions -********************************/ - -LZ4_stream_t* LZ4_createStream(void) -{ - LZ4_stream_t* const lz4s = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); - LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */ - DEBUGLOG(4, "LZ4_createStream %p", lz4s); - if (lz4s == NULL) return NULL; - LZ4_initStream(lz4s, sizeof(*lz4s)); - return lz4s; -} - -#ifndef _MSC_VER /* for some reason, Visual fails the aligment test on 32-bit x86 : - it reports an aligment of 8-bytes, - while actually aligning LZ4_stream_t on 4 bytes. */ -static size_t LZ4_stream_t_alignment(void) -{ - struct { char c; LZ4_stream_t t; } t_a; - return sizeof(t_a) - sizeof(t_a.t); -} -#endif - -LZ4_stream_t* LZ4_initStream (void* buffer, size_t size) -{ - DEBUGLOG(5, "LZ4_initStream"); - if (buffer == NULL) { return NULL; } - if (size < sizeof(LZ4_stream_t)) { return NULL; } -#ifndef _MSC_VER /* for some reason, Visual fails the aligment test on 32-bit x86 : - it reports an aligment of 8-bytes, - while actually aligning LZ4_stream_t on 4 bytes. */ - if (((size_t)buffer) & (LZ4_stream_t_alignment() - 1)) { return NULL; } /* alignment check */ -#endif - MEM_INIT(buffer, 0, sizeof(LZ4_stream_t)); - return (LZ4_stream_t*)buffer; -} - -/* resetStream is now deprecated, - * prefer initStream() which is more general */ -void LZ4_resetStream (LZ4_stream_t* LZ4_stream) -{ - DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream); - MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t)); -} - -void LZ4_resetStream_fast(LZ4_stream_t* ctx) { - LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32); -} - -int LZ4_freeStream (LZ4_stream_t* LZ4_stream) -{ - if (!LZ4_stream) return 0; /* support free on NULL */ - DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream); - FREEMEM(LZ4_stream); - return (0); -} - - -#define HASH_UNIT sizeof(reg_t) -int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize) -{ - LZ4_stream_t_internal* dict = &LZ4_dict->internal_donotuse; - const tableType_t tableType = byU32; - const BYTE* p = (const BYTE*)dictionary; - const BYTE* const dictEnd = p + dictSize; - const BYTE* base; - - DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict); - - /* It's necessary to reset the context, - * and not just continue it with prepareTable() - * to avoid any risk of generating overflowing matchIndex - * when compressing using this dictionary */ - LZ4_resetStream(LZ4_dict); - - /* We always increment the offset by 64 KB, since, if the dict is longer, - * we truncate it to the last 64k, and if it's shorter, we still want to - * advance by a whole window length so we can provide the guarantee that - * there are only valid offsets in the window, which allows an optimization - * in LZ4_compress_fast_continue() where it uses noDictIssue even when the - * dictionary isn't a full 64k. */ - dict->currentOffset += 64 KB; - - if (dictSize < (int)HASH_UNIT) { - return 0; - } - - if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB; - base = dictEnd - dict->currentOffset; - dict->dictionary = p; - dict->dictSize = (U32)(dictEnd - p); - dict->tableType = tableType; - - while (p <= dictEnd-HASH_UNIT) { - LZ4_putPosition(p, dict->hashTable, tableType, base); - p+=3; - } - - return (int)dict->dictSize; -} - -void LZ4_attach_dictionary(LZ4_stream_t* workingStream, const LZ4_stream_t* dictionaryStream) { - const LZ4_stream_t_internal* dictCtx = dictionaryStream == NULL ? NULL : - &(dictionaryStream->internal_donotuse); - - DEBUGLOG(4, "LZ4_attach_dictionary (%p, %p, size %u)", - workingStream, dictionaryStream, - dictCtx != NULL ? dictCtx->dictSize : 0); - - /* Calling LZ4_resetStream_fast() here makes sure that changes will not be - * erased by subsequent calls to LZ4_resetStream_fast() in case stream was - * marked as having dirty context, e.g. requiring full reset. - */ - LZ4_resetStream_fast(workingStream); - - if (dictCtx != NULL) { - /* If the current offset is zero, we will never look in the - * external dictionary context, since there is no value a table - * entry can take that indicate a miss. In that case, we need - * to bump the offset to something non-zero. - */ - if (workingStream->internal_donotuse.currentOffset == 0) { - workingStream->internal_donotuse.currentOffset = 64 KB; - } - - /* Don't actually attach an empty dictionary. - */ - if (dictCtx->dictSize == 0) { - dictCtx = NULL; - } - } - workingStream->internal_donotuse.dictCtx = dictCtx; -} - - -static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, int nextSize) -{ - assert(nextSize >= 0); - if (LZ4_dict->currentOffset + (unsigned)nextSize > 0x80000000) { /* potential ptrdiff_t overflow (32-bits mode) */ - /* rescale hash table */ - U32 const delta = LZ4_dict->currentOffset - 64 KB; - const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize; - int i; - DEBUGLOG(4, "LZ4_renormDictT"); - for (i=0; ihashTable[i] < delta) LZ4_dict->hashTable[i]=0; - else LZ4_dict->hashTable[i] -= delta; - } - LZ4_dict->currentOffset = 64 KB; - if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB; - LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize; - } -} - - -int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, - const char* source, char* dest, - int inputSize, int maxOutputSize, - int acceleration) -{ - const tableType_t tableType = byU32; - LZ4_stream_t_internal* streamPtr = &LZ4_stream->internal_donotuse; - const BYTE* dictEnd = streamPtr->dictionary + streamPtr->dictSize; - - DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i)", inputSize); - - if (streamPtr->dirty) { return 0; } /* Uninitialized structure detected */ - LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */ - if (acceleration < 1) acceleration = ACCELERATION_DEFAULT; - - /* invalidate tiny dictionaries */ - if ( (streamPtr->dictSize-1 < 4-1) /* intentional underflow */ - && (dictEnd != (const BYTE*)source) ) { - DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary); - streamPtr->dictSize = 0; - streamPtr->dictionary = (const BYTE*)source; - dictEnd = (const BYTE*)source; - } - - /* Check overlapping input/dictionary space */ - { const BYTE* sourceEnd = (const BYTE*) source + inputSize; - if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) { - streamPtr->dictSize = (U32)(dictEnd - sourceEnd); - if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB; - if (streamPtr->dictSize < 4) streamPtr->dictSize = 0; - streamPtr->dictionary = dictEnd - streamPtr->dictSize; - } - } - - /* prefix mode : source data follows dictionary */ - if (dictEnd == (const BYTE*)source) { - if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) - return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration); - else - return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration); - } - - /* external dictionary mode */ - { int result; - if (streamPtr->dictCtx) { - /* We depend here on the fact that dictCtx'es (produced by - * LZ4_loadDict) guarantee that their tables contain no references - * to offsets between dictCtx->currentOffset - 64 KB and - * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe - * to use noDictIssue even when the dict isn't a full 64 KB. - */ - if (inputSize > 4 KB) { - /* For compressing large blobs, it is faster to pay the setup - * cost to copy the dictionary's tables into the active context, - * so that the compression loop is only looking into one table. - */ - memcpy(streamPtr, streamPtr->dictCtx, sizeof(LZ4_stream_t)); - result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); - } else { - result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration); - } - } else { - if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { - result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration); - } else { - result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); - } - } - streamPtr->dictionary = (const BYTE*)source; - streamPtr->dictSize = (U32)inputSize; - return result; - } -} - - -/* Hidden debug function, to force-test external dictionary mode */ -int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize) -{ - LZ4_stream_t_internal* streamPtr = &LZ4_dict->internal_donotuse; - int result; - - LZ4_renormDictT(streamPtr, srcSize); - - if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { - result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1); - } else { - result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1); - } - - streamPtr->dictionary = (const BYTE*)source; - streamPtr->dictSize = (U32)srcSize; - - return result; -} - - -/*! LZ4_saveDict() : - * If previously compressed data block is not guaranteed to remain available at its memory location, - * save it into a safer place (char* safeBuffer). - * Note : you don't need to call LZ4_loadDict() afterwards, - * dictionary is immediately usable, you can therefore call LZ4_compress_fast_continue(). - * Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. - */ -int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize) -{ - LZ4_stream_t_internal* const dict = &LZ4_dict->internal_donotuse; - const BYTE* const previousDictEnd = dict->dictionary + dict->dictSize; - - if ((U32)dictSize > 64 KB) { dictSize = 64 KB; } /* useless to define a dictionary > 64 KB */ - if ((U32)dictSize > dict->dictSize) { dictSize = (int)dict->dictSize; } - - memmove(safeBuffer, previousDictEnd - dictSize, dictSize); - - dict->dictionary = (const BYTE*)safeBuffer; - dict->dictSize = (U32)dictSize; - - return dictSize; -} - - - -/*-******************************* - * Decompression functions - ********************************/ - -typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive; -typedef enum { decode_full_block = 0, partial_decode = 1 } earlyEnd_directive; - -#undef MIN -#define MIN(a,b) ( (a) < (b) ? (a) : (b) ) - -/* Read the variable-length literal or match length. - * - * ip - pointer to use as input. - * lencheck - end ip. Return an error if ip advances >= lencheck. - * loop_check - check ip >= lencheck in body of loop. Returns loop_error if so. - * initial_check - check ip >= lencheck before start of loop. Returns initial_error if so. - * error (output) - error code. Should be set to 0 before call. - */ -typedef enum { loop_error = -2, initial_error = -1, ok = 0 } variable_length_error; -LZ4_FORCE_INLINE unsigned -read_variable_length(const BYTE**ip, const BYTE* lencheck, int loop_check, int initial_check, variable_length_error* error) -{ - U32 length = 0; - U32 s; - if (initial_check && unlikely((*ip) >= lencheck)) { /* overflow detection */ - *error = initial_error; - return length; - } - do { - s = **ip; - (*ip)++; - length += s; - if (loop_check && unlikely((*ip) >= lencheck)) { /* overflow detection */ - *error = loop_error; - return length; - } - } while (s==255); - - return length; -} - -/*! LZ4_decompress_generic() : - * This generic decompression function covers all use cases. - * It shall be instantiated several times, using different sets of directives. - * Note that it is important for performance that this function really get inlined, - * in order to remove useless branches during compilation optimization. - */ -LZ4_FORCE_INLINE int -LZ4_decompress_generic( - const char* const src, - char* const dst, - int srcSize, - int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */ - - endCondition_directive endOnInput, /* endOnOutputSize, endOnInputSize */ - earlyEnd_directive partialDecoding, /* full, partial */ - dict_directive dict, /* noDict, withPrefix64k, usingExtDict */ - const BYTE* const lowPrefix, /* always <= dst, == dst when no prefix */ - const BYTE* const dictStart, /* only if dict==usingExtDict */ - const size_t dictSize /* note : = 0 if noDict */ - ) -{ - if (src == NULL) { return -1; } - - { const BYTE* ip = (const BYTE*) src; - const BYTE* const iend = ip + srcSize; - - BYTE* op = (BYTE*) dst; - BYTE* const oend = op + outputSize; - BYTE* cpy; - - const BYTE* const dictEnd = (dictStart == NULL) ? NULL : dictStart + dictSize; - - const int safeDecode = (endOnInput==endOnInputSize); - const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB))); - - - /* Set up the "end" pointers for the shortcut. */ - const BYTE* const shortiend = iend - (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/; - const BYTE* const shortoend = oend - (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/; - - const BYTE* match; - size_t offset; - unsigned token; - size_t length; - - - DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize); - - /* Special cases */ - assert(lowPrefix <= op); - if ((endOnInput) && (unlikely(outputSize==0))) { - /* Empty output buffer */ - if (partialDecoding) return 0; - return ((srcSize==1) && (*ip==0)) ? 0 : -1; - } - if ((!endOnInput) && (unlikely(outputSize==0))) { return (*ip==0 ? 1 : -1); } - if ((endOnInput) && unlikely(srcSize==0)) { return -1; } - - /* Currently the fast loop shows a regression on qualcomm arm chips. */ -#if LZ4_FAST_DEC_LOOP - if ((oend - op) < FASTLOOP_SAFE_DISTANCE) { - DEBUGLOG(6, "skip fast decode loop"); - goto safe_decode; - } - - /* Fast loop : decode sequences as long as output < iend-FASTLOOP_SAFE_DISTANCE */ - while (1) { - /* Main fastloop assertion: We can always wildcopy FASTLOOP_SAFE_DISTANCE */ - assert(oend - op >= FASTLOOP_SAFE_DISTANCE); - if (endOnInput) { assert(ip < iend); } - token = *ip++; - length = token >> ML_BITS; /* literal length */ - - assert(!endOnInput || ip <= iend); /* ip < iend before the increment */ - - /* decode literal length */ - if (length == RUN_MASK) { - variable_length_error error = ok; - length += read_variable_length(&ip, iend-RUN_MASK, endOnInput, endOnInput, &error); - if (error == initial_error) { goto _output_error; } - if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ - if ((safeDecode) && unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ - - /* copy literals */ - cpy = op+length; - LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); - if (endOnInput) { /* LZ4_decompress_safe() */ - if ((cpy>oend-32) || (ip+length>iend-32)) { goto safe_literal_copy; } - LZ4_wildCopy32(op, ip, cpy); - } else { /* LZ4_decompress_fast() */ - if (cpy>oend-8) { goto safe_literal_copy; } - LZ4_wildCopy8(op, ip, cpy); /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time : - * it doesn't know input length, and only relies on end-of-block properties */ - } - ip += length; op = cpy; - } else { - cpy = op+length; - if (endOnInput) { /* LZ4_decompress_safe() */ - DEBUGLOG(7, "copy %u bytes in a 16-bytes stripe", (unsigned)length); - /* We don't need to check oend, since we check it once for each loop below */ - if (ip > iend-(16 + 1/*max lit + offset + nextToken*/)) { goto safe_literal_copy; } - /* Literals can only be 14, but hope compilers optimize if we copy by a register size */ - memcpy(op, ip, 16); - } else { /* LZ4_decompress_fast() */ - /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time : - * it doesn't know input length, and relies on end-of-block properties */ - memcpy(op, ip, 8); - if (length > 8) { memcpy(op+8, ip+8, 8); } - } - ip += length; op = cpy; - } - - /* get offset */ - offset = LZ4_readLE16(ip); ip+=2; - match = op - offset; - assert(match <= op); - - /* get matchlength */ - length = token & ML_MASK; - - if (length == ML_MASK) { - variable_length_error error = ok; - if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ - length += read_variable_length(&ip, iend - LASTLITERALS + 1, endOnInput, 0, &error); - if (error != ok) { goto _output_error; } - if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) { goto _output_error; } /* overflow detection */ - length += MINMATCH; - if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { - goto safe_match_copy; - } - } else { - length += MINMATCH; - if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { - goto safe_match_copy; - } - - /* Fastpath check: Avoids a branch in LZ4_wildCopy32 if true */ - if ((dict == withPrefix64k) || (match >= lowPrefix)) { - if (offset >= 8) { - assert(match >= lowPrefix); - assert(match <= op); - assert(op + 18 <= oend); - - memcpy(op, match, 8); - memcpy(op+8, match+8, 8); - memcpy(op+16, match+16, 2); - op += length; - continue; - } } } - - if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ - /* match starting within external dictionary */ - if ((dict==usingExtDict) && (match < lowPrefix)) { - if (unlikely(op+length > oend-LASTLITERALS)) { - if (partialDecoding) { - length = MIN(length, (size_t)(oend-op)); /* reach end of buffer */ - } else { - goto _output_error; /* end-of-block condition violated */ - } } - - if (length <= (size_t)(lowPrefix-match)) { - /* match fits entirely within external dictionary : just copy */ - memmove(op, dictEnd - (lowPrefix-match), length); - op += length; - } else { - /* match stretches into both external dictionary and current block */ - size_t const copySize = (size_t)(lowPrefix - match); - size_t const restSize = length - copySize; - memcpy(op, dictEnd - copySize, copySize); - op += copySize; - if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ - BYTE* const endOfMatch = op + restSize; - const BYTE* copyFrom = lowPrefix; - while (op < endOfMatch) { *op++ = *copyFrom++; } - } else { - memcpy(op, lowPrefix, restSize); - op += restSize; - } } - continue; - } - - /* copy match within block */ - cpy = op + length; - - assert((op <= oend) && (oend-op >= 32)); - if (unlikely(offset<16)) { - LZ4_memcpy_using_offset(op, match, cpy, offset); - } else { - LZ4_wildCopy32(op, match, cpy); - } - - op = cpy; /* wildcopy correction */ - } - safe_decode: -#endif - - /* Main Loop : decode remaining sequences where output < FASTLOOP_SAFE_DISTANCE */ - while (1) { - token = *ip++; - length = token >> ML_BITS; /* literal length */ - - assert(!endOnInput || ip <= iend); /* ip < iend before the increment */ - - /* A two-stage shortcut for the most common case: - * 1) If the literal length is 0..14, and there is enough space, - * enter the shortcut and copy 16 bytes on behalf of the literals - * (in the fast mode, only 8 bytes can be safely copied this way). - * 2) Further if the match length is 4..18, copy 18 bytes in a similar - * manner; but we ensure that there's enough space in the output for - * those 18 bytes earlier, upon entering the shortcut (in other words, - * there is a combined check for both stages). - */ - if ( (endOnInput ? length != RUN_MASK : length <= 8) - /* strictly "less than" on input, to re-enter the loop with at least one byte */ - && likely((endOnInput ? ip < shortiend : 1) & (op <= shortoend)) ) { - /* Copy the literals */ - memcpy(op, ip, endOnInput ? 16 : 8); - op += length; ip += length; - - /* The second stage: prepare for match copying, decode full info. - * If it doesn't work out, the info won't be wasted. */ - length = token & ML_MASK; /* match length */ - offset = LZ4_readLE16(ip); ip += 2; - match = op - offset; - assert(match <= op); /* check overflow */ - - /* Do not deal with overlapping matches. */ - if ( (length != ML_MASK) - && (offset >= 8) - && (dict==withPrefix64k || match >= lowPrefix) ) { - /* Copy the match. */ - memcpy(op + 0, match + 0, 8); - memcpy(op + 8, match + 8, 8); - memcpy(op +16, match +16, 2); - op += length + MINMATCH; - /* Both stages worked, load the next token. */ - continue; - } - - /* The second stage didn't work out, but the info is ready. - * Propel it right to the point of match copying. */ - goto _copy_match; - } - - /* decode literal length */ - if (length == RUN_MASK) { - variable_length_error error = ok; - length += read_variable_length(&ip, iend-RUN_MASK, endOnInput, endOnInput, &error); - if (error == initial_error) { goto _output_error; } - if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ - if ((safeDecode) && unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ - } - - /* copy literals */ - cpy = op+length; -#if LZ4_FAST_DEC_LOOP - safe_literal_copy: -#endif - LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); - if ( ((endOnInput) && ((cpy>oend-MFLIMIT) || (ip+length>iend-(2+1+LASTLITERALS))) ) - || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH)) ) - { - /* We've either hit the input parsing restriction or the output parsing restriction. - * If we've hit the input parsing condition then this must be the last sequence. - * If we've hit the output parsing condition then we are either using partialDecoding - * or we've hit the output parsing condition. - */ - if (partialDecoding) { - /* Since we are partial decoding we may be in this block because of the output parsing - * restriction, which is not valid since the output buffer is allowed to be undersized. - */ - assert(endOnInput); - /* If we're in this block because of the input parsing condition, then we must be on the - * last sequence (or invalid), so we must check that we exactly consume the input. - */ - if ((ip+length>iend-(2+1+LASTLITERALS)) && (ip+length != iend)) { goto _output_error; } - assert(ip+length <= iend); - /* We are finishing in the middle of a literals segment. - * Break after the copy. - */ - if (cpy > oend) { - cpy = oend; - assert(op<=oend); - length = (size_t)(oend-op); - } - assert(ip+length <= iend); - } else { - /* We must be on the last sequence because of the parsing limitations so check - * that we exactly regenerate the original size (must be exact when !endOnInput). - */ - if ((!endOnInput) && (cpy != oend)) { goto _output_error; } - /* We must be on the last sequence (or invalid) because of the parsing limitations - * so check that we exactly consume the input and don't overrun the output buffer. - */ - if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) { goto _output_error; } - } - memmove(op, ip, length); /* supports overlapping memory regions, which only matters for in-place decompression scenarios */ - ip += length; - op += length; - /* Necessarily EOF when !partialDecoding. When partialDecoding - * it is EOF if we've either filled the output buffer or hit - * the input parsing restriction. - */ - if (!partialDecoding || (cpy == oend) || (ip == iend)) { - break; - } - } else { - LZ4_wildCopy8(op, ip, cpy); /* may overwrite up to WILDCOPYLENGTH beyond cpy */ - ip += length; op = cpy; - } - - /* get offset */ - offset = LZ4_readLE16(ip); ip+=2; - match = op - offset; - - /* get matchlength */ - length = token & ML_MASK; - - _copy_match: - if (length == ML_MASK) { - variable_length_error error = ok; - length += read_variable_length(&ip, iend - LASTLITERALS + 1, endOnInput, 0, &error); - if (error != ok) goto _output_error; - if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) goto _output_error; /* overflow detection */ - } - length += MINMATCH; - -#if LZ4_FAST_DEC_LOOP - safe_match_copy: -#endif - if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) goto _output_error; /* Error : offset outside buffers */ - /* match starting within external dictionary */ - if ((dict==usingExtDict) && (match < lowPrefix)) { - if (unlikely(op+length > oend-LASTLITERALS)) { - if (partialDecoding) length = MIN(length, (size_t)(oend-op)); - else goto _output_error; /* doesn't respect parsing restriction */ - } - - if (length <= (size_t)(lowPrefix-match)) { - /* match fits entirely within external dictionary : just copy */ - memmove(op, dictEnd - (lowPrefix-match), length); - op += length; - } else { - /* match stretches into both external dictionary and current block */ - size_t const copySize = (size_t)(lowPrefix - match); - size_t const restSize = length - copySize; - memcpy(op, dictEnd - copySize, copySize); - op += copySize; - if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ - BYTE* const endOfMatch = op + restSize; - const BYTE* copyFrom = lowPrefix; - while (op < endOfMatch) *op++ = *copyFrom++; - } else { - memcpy(op, lowPrefix, restSize); - op += restSize; - } } - continue; - } - assert(match >= lowPrefix); - - /* copy match within block */ - cpy = op + length; - - /* partialDecoding : may end anywhere within the block */ - assert(op<=oend); - if (partialDecoding && (cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { - size_t const mlen = MIN(length, (size_t)(oend-op)); - const BYTE* const matchEnd = match + mlen; - BYTE* const copyEnd = op + mlen; - if (matchEnd > op) { /* overlap copy */ - while (op < copyEnd) { *op++ = *match++; } - } else { - memcpy(op, match, mlen); - } - op = copyEnd; - if (op == oend) { break; } - continue; - } - - if (unlikely(offset<8)) { - LZ4_write32(op, 0); /* silence msan warning when offset==0 */ - op[0] = match[0]; - op[1] = match[1]; - op[2] = match[2]; - op[3] = match[3]; - match += inc32table[offset]; - memcpy(op+4, match, 4); - match -= dec64table[offset]; - } else { - memcpy(op, match, 8); - match += 8; - } - op += 8; - - if (unlikely(cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { - BYTE* const oCopyLimit = oend - (WILDCOPYLENGTH-1); - if (cpy > oend-LASTLITERALS) { goto _output_error; } /* Error : last LASTLITERALS bytes must be literals (uncompressed) */ - if (op < oCopyLimit) { - LZ4_wildCopy8(op, match, oCopyLimit); - match += oCopyLimit - op; - op = oCopyLimit; - } - while (op < cpy) { *op++ = *match++; } - } else { - memcpy(op, match, 8); - if (length > 16) { LZ4_wildCopy8(op+8, match+8, cpy); } - } - op = cpy; /* wildcopy correction */ - } - - /* end of decoding */ - if (endOnInput) { - return (int) (((char*)op)-dst); /* Nb of output bytes decoded */ - } else { - return (int) (((const char*)ip)-src); /* Nb of input bytes read */ - } - - /* Overflow error detected */ - _output_error: - return (int) (-(((const char*)ip)-src))-1; - } -} - - -/*===== Instantiate the API decoding functions. =====*/ - -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize) -{ - return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, - endOnInputSize, decode_full_block, noDict, - (BYTE*)dest, NULL, 0); -} - -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_safe_partial(const char* src, char* dst, int compressedSize, int targetOutputSize, int dstCapacity) -{ - dstCapacity = MIN(targetOutputSize, dstCapacity); - return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity, - endOnInputSize, partial_decode, - noDict, (BYTE*)dst, NULL, 0); -} - -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_fast(const char* source, char* dest, int originalSize) -{ - return LZ4_decompress_generic(source, dest, 0, originalSize, - endOnOutputSize, decode_full_block, withPrefix64k, - (BYTE*)dest - 64 KB, NULL, 0); -} - -/*===== Instantiate a few more decoding cases, used more than once. =====*/ - -LZ4_FORCE_O2_GCC_PPC64LE /* Exported, an obsolete API function. */ -int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize) -{ - return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, - endOnInputSize, decode_full_block, withPrefix64k, - (BYTE*)dest - 64 KB, NULL, 0); -} - -/* Another obsolete API function, paired with the previous one. */ -int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize) -{ - /* LZ4_decompress_fast doesn't validate match offsets, - * and thus serves well with any prefixed dictionary. */ - return LZ4_decompress_fast(source, dest, originalSize); -} - -LZ4_FORCE_O2_GCC_PPC64LE -static int LZ4_decompress_safe_withSmallPrefix(const char* source, char* dest, int compressedSize, int maxOutputSize, - size_t prefixSize) -{ - return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, - endOnInputSize, decode_full_block, noDict, - (BYTE*)dest-prefixSize, NULL, 0); -} - -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, - int compressedSize, int maxOutputSize, - const void* dictStart, size_t dictSize) -{ - return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, - endOnInputSize, decode_full_block, usingExtDict, - (BYTE*)dest, (const BYTE*)dictStart, dictSize); -} - -LZ4_FORCE_O2_GCC_PPC64LE -static int LZ4_decompress_fast_extDict(const char* source, char* dest, int originalSize, - const void* dictStart, size_t dictSize) -{ - return LZ4_decompress_generic(source, dest, 0, originalSize, - endOnOutputSize, decode_full_block, usingExtDict, - (BYTE*)dest, (const BYTE*)dictStart, dictSize); -} - -/* The "double dictionary" mode, for use with e.g. ring buffers: the first part - * of the dictionary is passed as prefix, and the second via dictStart + dictSize. - * These routines are used only once, in LZ4_decompress_*_continue(). - */ -LZ4_FORCE_INLINE -int LZ4_decompress_safe_doubleDict(const char* source, char* dest, int compressedSize, int maxOutputSize, - size_t prefixSize, const void* dictStart, size_t dictSize) -{ - return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, - endOnInputSize, decode_full_block, usingExtDict, - (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize); -} - -LZ4_FORCE_INLINE -int LZ4_decompress_fast_doubleDict(const char* source, char* dest, int originalSize, - size_t prefixSize, const void* dictStart, size_t dictSize) -{ - return LZ4_decompress_generic(source, dest, 0, originalSize, - endOnOutputSize, decode_full_block, usingExtDict, - (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize); -} - -/*===== streaming decompression functions =====*/ - -LZ4_streamDecode_t* LZ4_createStreamDecode(void) -{ - LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t)); - LZ4_STATIC_ASSERT(LZ4_STREAMDECODESIZE >= sizeof(LZ4_streamDecode_t_internal)); /* A compilation error here means LZ4_STREAMDECODESIZE is not large enough */ - return lz4s; -} - -int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream) -{ - if (LZ4_stream == NULL) { return 0; } /* support free on NULL */ - FREEMEM(LZ4_stream); - return 0; -} - -/*! LZ4_setStreamDecode() : - * Use this function to instruct where to find the dictionary. - * This function is not necessary if previous data is still available where it was decoded. - * Loading a size of 0 is allowed (same effect as no dictionary). - * @return : 1 if OK, 0 if error - */ -int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize) -{ - LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; - lz4sd->prefixSize = (size_t) dictSize; - lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize; - lz4sd->externalDict = NULL; - lz4sd->extDictSize = 0; - return 1; -} - -/*! LZ4_decoderRingBufferSize() : - * when setting a ring buffer for streaming decompression (optional scenario), - * provides the minimum size of this ring buffer - * to be compatible with any source respecting maxBlockSize condition. - * Note : in a ring buffer scenario, - * blocks are presumed decompressed next to each other. - * When not enough space remains for next block (remainingSize < maxBlockSize), - * decoding resumes from beginning of ring buffer. - * @return : minimum ring buffer size, - * or 0 if there is an error (invalid maxBlockSize). - */ -int LZ4_decoderRingBufferSize(int maxBlockSize) -{ - if (maxBlockSize < 0) return 0; - if (maxBlockSize > LZ4_MAX_INPUT_SIZE) return 0; - if (maxBlockSize < 16) maxBlockSize = 16; - return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize); -} - -/* -*_continue() : - These decoding functions allow decompression of multiple blocks in "streaming" mode. - Previously decoded blocks must still be available at the memory position where they were decoded. - If it's not possible, save the relevant part of decoded data into a safe buffer, - and indicate where it stands using LZ4_setStreamDecode() -*/ -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize) -{ - LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; - int result; - - if (lz4sd->prefixSize == 0) { - /* The first call, no dictionary yet. */ - assert(lz4sd->extDictSize == 0); - result = LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); - if (result <= 0) return result; - lz4sd->prefixSize = (size_t)result; - lz4sd->prefixEnd = (BYTE*)dest + result; - } else if (lz4sd->prefixEnd == (BYTE*)dest) { - /* They're rolling the current segment. */ - if (lz4sd->prefixSize >= 64 KB - 1) - result = LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); - else if (lz4sd->extDictSize == 0) - result = LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, - lz4sd->prefixSize); - else - result = LZ4_decompress_safe_doubleDict(source, dest, compressedSize, maxOutputSize, - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); - if (result <= 0) return result; - lz4sd->prefixSize += (size_t)result; - lz4sd->prefixEnd += result; - } else { - /* The buffer wraps around, or they're switching to another buffer. */ - lz4sd->extDictSize = lz4sd->prefixSize; - lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; - result = LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, - lz4sd->externalDict, lz4sd->extDictSize); - if (result <= 0) return result; - lz4sd->prefixSize = (size_t)result; - lz4sd->prefixEnd = (BYTE*)dest + result; - } - - return result; -} - -LZ4_FORCE_O2_GCC_PPC64LE -int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize) -{ - LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; - int result; - assert(originalSize >= 0); - - if (lz4sd->prefixSize == 0) { - assert(lz4sd->extDictSize == 0); - result = LZ4_decompress_fast(source, dest, originalSize); - if (result <= 0) return result; - lz4sd->prefixSize = (size_t)originalSize; - lz4sd->prefixEnd = (BYTE*)dest + originalSize; - } else if (lz4sd->prefixEnd == (BYTE*)dest) { - if (lz4sd->prefixSize >= 64 KB - 1 || lz4sd->extDictSize == 0) - result = LZ4_decompress_fast(source, dest, originalSize); - else - result = LZ4_decompress_fast_doubleDict(source, dest, originalSize, - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); - if (result <= 0) return result; - lz4sd->prefixSize += (size_t)originalSize; - lz4sd->prefixEnd += originalSize; - } else { - lz4sd->extDictSize = lz4sd->prefixSize; - lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; - result = LZ4_decompress_fast_extDict(source, dest, originalSize, - lz4sd->externalDict, lz4sd->extDictSize); - if (result <= 0) return result; - lz4sd->prefixSize = (size_t)originalSize; - lz4sd->prefixEnd = (BYTE*)dest + originalSize; - } - - return result; -} - - -/* -Advanced decoding functions : -*_usingDict() : - These decoding functions work the same as "_continue" ones, - the dictionary must be explicitly provided within parameters -*/ - -int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) -{ - if (dictSize==0) - return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); - if (dictStart+dictSize == dest) { - if (dictSize >= 64 KB - 1) { - return LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); - } - assert(dictSize >= 0); - return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, (size_t)dictSize); - } - assert(dictSize >= 0); - return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, (size_t)dictSize); -} - -int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize) -{ - if (dictSize==0 || dictStart+dictSize == dest) - return LZ4_decompress_fast(source, dest, originalSize); - assert(dictSize >= 0); - return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, (size_t)dictSize); -} - - -/*=************************************************* -* Obsolete Functions -***************************************************/ -/* obsolete compression functions */ -int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) -{ - return LZ4_compress_default(source, dest, inputSize, maxOutputSize); -} -int LZ4_compress(const char* src, char* dest, int srcSize) -{ - return LZ4_compress_default(src, dest, srcSize, LZ4_compressBound(srcSize)); -} -int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize) -{ - return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1); -} -int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize) -{ - return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1); -} -int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int dstCapacity) -{ - return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1); -} -int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize) -{ - return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1); -} - -/* -These decompression functions are deprecated and should no longer be used. -They are only provided here for compatibility with older user programs. -- LZ4_uncompress is totally equivalent to LZ4_decompress_fast -- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe -*/ -int LZ4_uncompress (const char* source, char* dest, int outputSize) -{ - return LZ4_decompress_fast(source, dest, outputSize); -} -int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) -{ - return LZ4_decompress_safe(source, dest, isize, maxOutputSize); -} - -/* Obsolete Streaming functions */ - -int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; } - -int LZ4_resetStreamState(void* state, char* inputBuffer) -{ - (void)inputBuffer; - LZ4_resetStream((LZ4_stream_t*)state); - return 0; -} - -void* LZ4_create (char* inputBuffer) -{ - (void)inputBuffer; - return LZ4_createStream(); -} + Copyright (C) 2011-2020, Yann Collet. + + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + You can contact the author at : + - LZ4 homepage : http://www.lz4.org + - LZ4 source repository : https://github.com/lz4/lz4 +*/ + +/*-************************************ +* Tuning parameters +**************************************/ +/* + * LZ4_HEAPMODE : + * Select how default compression functions will allocate memory for their hash table, + * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()). + */ +#ifndef LZ4_HEAPMODE +# define LZ4_HEAPMODE 0 +#endif + +/* + * LZ4_ACCELERATION_DEFAULT : + * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0 + */ +#define LZ4_ACCELERATION_DEFAULT 1 +/* + * LZ4_ACCELERATION_MAX : + * Any "acceleration" value higher than this threshold + * get treated as LZ4_ACCELERATION_MAX instead (fix #876) + */ +#define LZ4_ACCELERATION_MAX 65537 + + +/*-************************************ +* CPU Feature Detection +**************************************/ +/* LZ4_FORCE_MEMORY_ACCESS + * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. + * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. + * The below switch allow to select different access method for improved performance. + * Method 0 (default) : use `memcpy()`. Safe and portable. + * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). + * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. + * Method 2 : direct access. This method is portable but violate C standard. + * It can generate buggy code on targets which assembly generation depends on alignment. + * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) + * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. + * Prefer these methods in priority order (0 > 1 > 2) + */ +#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */ +# if defined(__GNUC__) && \ + ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) \ + || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) +# define LZ4_FORCE_MEMORY_ACCESS 2 +# elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__) +# define LZ4_FORCE_MEMORY_ACCESS 1 +# endif +#endif + +/* + * LZ4_FORCE_SW_BITCOUNT + * Define this parameter if your target system or compiler does not support hardware bit count + */ +#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */ +# undef LZ4_FORCE_SW_BITCOUNT /* avoid double def */ +# define LZ4_FORCE_SW_BITCOUNT +#endif + + + +/*-************************************ +* Dependency +**************************************/ +/* + * LZ4_SRC_INCLUDED: + * Amalgamation flag, whether lz4.c is included + */ +#ifndef LZ4_SRC_INCLUDED +# define LZ4_SRC_INCLUDED 1 +#endif + +#ifndef LZ4_STATIC_LINKING_ONLY +#define LZ4_STATIC_LINKING_ONLY +#endif + +#ifndef LZ4_DISABLE_DEPRECATE_WARNINGS +#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */ +#endif + +#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */ +#include "lz4.h" +/* see also "memory routines" below */ + + +/*-************************************ +* Compiler Options +**************************************/ +#if defined(_MSC_VER) && (_MSC_VER >= 1400) /* Visual Studio 2005+ */ +# include /* only present in VS2005+ */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +# pragma warning(disable : 6237) /* disable: C6237: conditional expression is always 0 */ +#endif /* _MSC_VER */ + +#ifndef LZ4_FORCE_INLINE +# ifdef _MSC_VER /* Visual Studio */ +# define LZ4_FORCE_INLINE static __forceinline +# else +# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# ifdef __GNUC__ +# define LZ4_FORCE_INLINE static inline __attribute__((always_inline)) +# else +# define LZ4_FORCE_INLINE static inline +# endif +# else +# define LZ4_FORCE_INLINE static +# endif /* __STDC_VERSION__ */ +# endif /* _MSC_VER */ +#endif /* LZ4_FORCE_INLINE */ + +/* LZ4_FORCE_O2 and LZ4_FORCE_INLINE + * gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy8, + * together with a simple 8-byte copy loop as a fall-back path. + * However, this optimization hurts the decompression speed by >30%, + * because the execution does not go to the optimized loop + * for typical compressible data, and all of the preamble checks + * before going to the fall-back path become useless overhead. + * This optimization happens only with the -O3 flag, and -O2 generates + * a simple 8-byte copy loop. + * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy8 + * functions are annotated with __attribute__((optimize("O2"))), + * and also LZ4_wildCopy8 is forcibly inlined, so that the O2 attribute + * of LZ4_wildCopy8 does not affect the compression speed. + */ +#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__) && !defined(__clang__) +# define LZ4_FORCE_O2 __attribute__((optimize("O2"))) +# undef LZ4_FORCE_INLINE +# define LZ4_FORCE_INLINE static __inline __attribute__((optimize("O2"),always_inline)) +#else +# define LZ4_FORCE_O2 +#endif + +#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__) +# define expect(expr,value) (__builtin_expect ((expr),(value)) ) +#else +# define expect(expr,value) (expr) +#endif + +#ifndef likely +#define likely(expr) expect((expr) != 0, 1) +#endif +#ifndef unlikely +#define unlikely(expr) expect((expr) != 0, 0) +#endif + +/* Should the alignment test prove unreliable, for some reason, + * it can be disabled by setting LZ4_ALIGN_TEST to 0 */ +#ifndef LZ4_ALIGN_TEST /* can be externally provided */ +# define LZ4_ALIGN_TEST 1 +#endif + + +/*-************************************ +* Memory routines +**************************************/ + +/*! LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION : + * Disable relatively high-level LZ4/HC functions that use dynamic memory + * allocation functions (malloc(), calloc(), free()). + * + * Note that this is a compile-time switch. And since it disables + * public/stable LZ4 v1 API functions, we don't recommend using this + * symbol to generate a library for distribution. + * + * The following public functions are removed when this symbol is defined. + * - lz4 : LZ4_createStream, LZ4_freeStream, + * LZ4_createStreamDecode, LZ4_freeStreamDecode, LZ4_create (deprecated) + * - lz4hc : LZ4_createStreamHC, LZ4_freeStreamHC, + * LZ4_createHC (deprecated), LZ4_freeHC (deprecated) + * - lz4frame, lz4file : All LZ4F_* functions + */ +#if defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) +# define ALLOC(s) lz4_error_memory_allocation_is_disabled +# define ALLOC_AND_ZERO(s) lz4_error_memory_allocation_is_disabled +# define FREEMEM(p) lz4_error_memory_allocation_is_disabled +#elif defined(LZ4_USER_MEMORY_FUNCTIONS) +/* memory management functions can be customized by user project. + * Below functions must exist somewhere in the Project + * and be available at link time */ +void* LZ4_malloc(size_t s); +void* LZ4_calloc(size_t n, size_t s); +void LZ4_free(void* p); +# define ALLOC(s) LZ4_malloc(s) +# define ALLOC_AND_ZERO(s) LZ4_calloc(1,s) +# define FREEMEM(p) LZ4_free(p) +#else +# include /* malloc, calloc, free */ +# define ALLOC(s) malloc(s) +# define ALLOC_AND_ZERO(s) calloc(1,s) +# define FREEMEM(p) free(p) +#endif + +#if ! LZ4_FREESTANDING +# include /* memset, memcpy */ +#endif +#if !defined(LZ4_memset) +# define LZ4_memset(p,v,s) memset((p),(v),(s)) +#endif +#define MEM_INIT(p,v,s) LZ4_memset((p),(v),(s)) + + +/*-************************************ +* Common Constants +**************************************/ +#define MINMATCH 4 + +#define WILDCOPYLENGTH 8 +#define LASTLITERALS 5 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ +#define MFLIMIT 12 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ +#define MATCH_SAFEGUARD_DISTANCE ((2*WILDCOPYLENGTH) - MINMATCH) /* ensure it's possible to write 2 x wildcopyLength without overflowing output buffer */ +#define FASTLOOP_SAFE_DISTANCE 64 +static const int LZ4_minLength = (MFLIMIT+1); + +#define KB *(1 <<10) +#define MB *(1 <<20) +#define GB *(1U<<30) + +#define LZ4_DISTANCE_ABSOLUTE_MAX 65535 +#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */ +# error "LZ4_DISTANCE_MAX is too big : must be <= 65535" +#endif + +#define ML_BITS 4 +#define ML_MASK ((1U<=1) +# include +#else +# ifndef assert +# define assert(condition) ((void)0) +# endif +#endif + +#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use after variable declarations */ + +#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2) +# include + static int g_debuglog_enable = 1; +# define DEBUGLOG(l, ...) { \ + if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \ + fprintf(stderr, __FILE__ ": "); \ + fprintf(stderr, __VA_ARGS__); \ + fprintf(stderr, " \n"); \ + } } +#else +# define DEBUGLOG(l, ...) {} /* disabled */ +#endif + +static int LZ4_isAligned(const void* ptr, size_t alignment) +{ + return ((size_t)ptr & (alignment -1)) == 0; +} + + +/*-************************************ +* Types +**************************************/ +#include +#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +# include + typedef uint8_t BYTE; + typedef uint16_t U16; + typedef uint32_t U32; + typedef int32_t S32; + typedef uint64_t U64; + typedef uintptr_t uptrval; +#else +# if UINT_MAX != 4294967295UL +# error "LZ4 code (when not C++ or C99) assumes that sizeof(int) == 4" +# endif + typedef unsigned char BYTE; + typedef unsigned short U16; + typedef unsigned int U32; + typedef signed int S32; + typedef unsigned long long U64; + typedef size_t uptrval; /* generally true, except OpenVMS-64 */ +#endif + +#if defined(__x86_64__) + typedef U64 reg_t; /* 64-bits in x32 mode */ +#else + typedef size_t reg_t; /* 32-bits in x32 mode */ +#endif + +typedef enum { + notLimited = 0, + limitedOutput = 1, + fillOutput = 2 +} limitedOutput_directive; + + +/*-************************************ +* Reading and writing into memory +**************************************/ + +/** + * LZ4 relies on memcpy with a constant size being inlined. In freestanding + * environments, the compiler can't assume the implementation of memcpy() is + * standard compliant, so it can't apply its specialized memcpy() inlining + * logic. When possible, use __builtin_memcpy() to tell the compiler to analyze + * memcpy() as if it were standard compliant, so it can inline it in freestanding + * environments. This is needed when decompressing the Linux Kernel, for example. + */ +#if !defined(LZ4_memcpy) +# if defined(__GNUC__) && (__GNUC__ >= 4) +# define LZ4_memcpy(dst, src, size) __builtin_memcpy(dst, src, size) +# else +# define LZ4_memcpy(dst, src, size) memcpy(dst, src, size) +# endif +#endif + +#if !defined(LZ4_memmove) +# if defined(__GNUC__) && (__GNUC__ >= 4) +# define LZ4_memmove __builtin_memmove +# else +# define LZ4_memmove memmove +# endif +#endif + +static unsigned LZ4_isLittleEndian(void) +{ + const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ + return one.c[0]; +} + + +#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2) +/* lie to the compiler about data alignment; use with caution */ + +static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; } +static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; } +static reg_t LZ4_read_ARCH(const void* memPtr) { return *(const reg_t*) memPtr; } + +static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; } +static void LZ4_write32(void* memPtr, U32 value) { *(U32*)memPtr = value; } + +#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1) + +/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ +/* currently only defined for gcc and icc */ +typedef union { U16 u16; U32 u32; reg_t uArch; } __attribute__((packed)) LZ4_unalign; + +static U16 LZ4_read16(const void* ptr) { return ((const LZ4_unalign*)ptr)->u16; } +static U32 LZ4_read32(const void* ptr) { return ((const LZ4_unalign*)ptr)->u32; } +static reg_t LZ4_read_ARCH(const void* ptr) { return ((const LZ4_unalign*)ptr)->uArch; } + +static void LZ4_write16(void* memPtr, U16 value) { ((LZ4_unalign*)memPtr)->u16 = value; } +static void LZ4_write32(void* memPtr, U32 value) { ((LZ4_unalign*)memPtr)->u32 = value; } + +#else /* safe and portable access using memcpy() */ + +static U16 LZ4_read16(const void* memPtr) +{ + U16 val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static U32 LZ4_read32(const void* memPtr) +{ + U32 val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static reg_t LZ4_read_ARCH(const void* memPtr) +{ + reg_t val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static void LZ4_write16(void* memPtr, U16 value) +{ + LZ4_memcpy(memPtr, &value, sizeof(value)); +} + +static void LZ4_write32(void* memPtr, U32 value) +{ + LZ4_memcpy(memPtr, &value, sizeof(value)); +} + +#endif /* LZ4_FORCE_MEMORY_ACCESS */ + + +static U16 LZ4_readLE16(const void* memPtr) +{ + if (LZ4_isLittleEndian()) { + return LZ4_read16(memPtr); + } else { + const BYTE* p = (const BYTE*)memPtr; + return (U16)((U16)p[0] + (p[1]<<8)); + } +} + +static void LZ4_writeLE16(void* memPtr, U16 value) +{ + if (LZ4_isLittleEndian()) { + LZ4_write16(memPtr, value); + } else { + BYTE* p = (BYTE*)memPtr; + p[0] = (BYTE) value; + p[1] = (BYTE)(value>>8); + } +} + +/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */ +LZ4_FORCE_INLINE +void LZ4_wildCopy8(void* dstPtr, const void* srcPtr, void* dstEnd) +{ + BYTE* d = (BYTE*)dstPtr; + const BYTE* s = (const BYTE*)srcPtr; + BYTE* const e = (BYTE*)dstEnd; + + do { LZ4_memcpy(d,s,8); d+=8; s+=8; } while (d= 16. */ +LZ4_FORCE_INLINE void +LZ4_wildCopy32(void* dstPtr, const void* srcPtr, void* dstEnd) +{ + BYTE* d = (BYTE*)dstPtr; + const BYTE* s = (const BYTE*)srcPtr; + BYTE* const e = (BYTE*)dstEnd; + + do { LZ4_memcpy(d,s,16); LZ4_memcpy(d+16,s+16,16); d+=32; s+=32; } while (d= dstPtr + MINMATCH + * - there is at least 8 bytes available to write after dstEnd */ +LZ4_FORCE_INLINE void +LZ4_memcpy_using_offset(BYTE* dstPtr, const BYTE* srcPtr, BYTE* dstEnd, const size_t offset) +{ + BYTE v[8]; + + assert(dstEnd >= dstPtr + MINMATCH); + + switch(offset) { + case 1: + MEM_INIT(v, *srcPtr, 8); + break; + case 2: + LZ4_memcpy(v, srcPtr, 2); + LZ4_memcpy(&v[2], srcPtr, 2); +#if defined(_MSC_VER) && (_MSC_VER <= 1933) /* MSVC 2022 ver 17.3 or earlier */ +# pragma warning(push) +# pragma warning(disable : 6385) /* warning C6385: Reading invalid data from 'v'. */ +#endif + LZ4_memcpy(&v[4], v, 4); +#if defined(_MSC_VER) && (_MSC_VER <= 1933) /* MSVC 2022 ver 17.3 or earlier */ +# pragma warning(pop) +#endif + break; + case 4: + LZ4_memcpy(v, srcPtr, 4); + LZ4_memcpy(&v[4], srcPtr, 4); + break; + default: + LZ4_memcpy_using_offset_base(dstPtr, srcPtr, dstEnd, offset); + return; + } + + LZ4_memcpy(dstPtr, v, 8); + dstPtr += 8; + while (dstPtr < dstEnd) { + LZ4_memcpy(dstPtr, v, 8); + dstPtr += 8; + } +} +#endif + + +/*-************************************ +* Common functions +**************************************/ +static unsigned LZ4_NbCommonBytes (reg_t val) +{ + assert(val != 0); + if (LZ4_isLittleEndian()) { + if (sizeof(val) == 8) { +# if defined(_MSC_VER) && (_MSC_VER >= 1800) && (defined(_M_AMD64) && !defined(_M_ARM64EC)) && !defined(LZ4_FORCE_SW_BITCOUNT) +/*-************************************************************************************************* +* ARM64EC is a Microsoft-designed ARM64 ABI compatible with AMD64 applications on ARM64 Windows 11. +* The ARM64EC ABI does not support AVX/AVX2/AVX512 instructions, nor their relevant intrinsics +* including _tzcnt_u64. Therefore, we need to neuter the _tzcnt_u64 code path for ARM64EC. +****************************************************************************************************/ +# if defined(__clang__) && (__clang_major__ < 10) + /* Avoid undefined clang-cl intrinsics issue. + * See https://github.com/lz4/lz4/pull/1017 for details. */ + return (unsigned)__builtin_ia32_tzcnt_u64(val) >> 3; +# else + /* x64 CPUS without BMI support interpret `TZCNT` as `REP BSF` */ + return (unsigned)_tzcnt_u64(val) >> 3; +# endif +# elif defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r = 0; + _BitScanForward64(&r, (U64)val); + return (unsigned)r >> 3; +# elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_ctzll((U64)val) >> 3; +# else + const U64 m = 0x0101010101010101ULL; + val ^= val - 1; + return (unsigned)(((U64)((val & (m - 1)) * m)) >> 56); +# endif + } else /* 32 bits */ { +# if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r; + _BitScanForward(&r, (U32)val); + return (unsigned)r >> 3; +# elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_ctz((U32)val) >> 3; +# else + const U32 m = 0x01010101; + return (unsigned)((((val - 1) ^ val) & (m - 1)) * m) >> 24; +# endif + } + } else /* Big Endian CPU */ { + if (sizeof(val)==8) { +# if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_clzll((U64)val) >> 3; +# else +#if 1 + /* this method is probably faster, + * but adds a 128 bytes lookup table */ + static const unsigned char ctz7_tab[128] = { + 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + }; + U64 const mask = 0x0101010101010101ULL; + U64 const t = (((val >> 8) - mask) | val) & mask; + return ctz7_tab[(t * 0x0080402010080402ULL) >> 57]; +#else + /* this method doesn't consume memory space like the previous one, + * but it contains several branches, + * that may end up slowing execution */ + static const U32 by32 = sizeof(val)*4; /* 32 on 64 bits (goal), 16 on 32 bits. + Just to avoid some static analyzer complaining about shift by 32 on 32-bits target. + Note that this code path is never triggered in 32-bits mode. */ + unsigned r; + if (!(val>>by32)) { r=4; } else { r=0; val>>=by32; } + if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; } + r += (!val); + return r; +#endif +# endif + } else /* 32 bits */ { +# if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_clz((U32)val) >> 3; +# else + val >>= 8; + val = ((((val + 0x00FFFF00) | 0x00FFFFFF) + val) | + (val + 0x00FF0000)) >> 24; + return (unsigned)val ^ 3; +# endif + } + } +} + + +#define STEPSIZE sizeof(reg_t) +LZ4_FORCE_INLINE +unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit) +{ + const BYTE* const pStart = pIn; + + if (likely(pIn < pInLimit-(STEPSIZE-1))) { + reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); + if (!diff) { + pIn+=STEPSIZE; pMatch+=STEPSIZE; + } else { + return LZ4_NbCommonBytes(diff); + } } + + while (likely(pIn < pInLimit-(STEPSIZE-1))) { + reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); + if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; } + pIn += LZ4_NbCommonBytes(diff); + return (unsigned)(pIn - pStart); + } + + if ((STEPSIZE==8) && (pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; } + if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; } + if ((pIn compression run slower on incompressible data */ + + +/*-************************************ +* Local Structures and types +**************************************/ +typedef enum { clearedTable = 0, byPtr, byU32, byU16 } tableType_t; + +/** + * This enum distinguishes several different modes of accessing previous + * content in the stream. + * + * - noDict : There is no preceding content. + * - withPrefix64k : Table entries up to ctx->dictSize before the current blob + * blob being compressed are valid and refer to the preceding + * content (of length ctx->dictSize), which is available + * contiguously preceding in memory the content currently + * being compressed. + * - usingExtDict : Like withPrefix64k, but the preceding content is somewhere + * else in memory, starting at ctx->dictionary with length + * ctx->dictSize. + * - usingDictCtx : Everything concerning the preceding content is + * in a separate context, pointed to by ctx->dictCtx. + * ctx->dictionary, ctx->dictSize, and table entries + * in the current context that refer to positions + * preceding the beginning of the current compression are + * ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx + * ->dictSize describe the location and size of the preceding + * content, and matches are found by looking in the ctx + * ->dictCtx->hashTable. + */ +typedef enum { noDict = 0, withPrefix64k, usingExtDict, usingDictCtx } dict_directive; +typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive; + + +/*-************************************ +* Local Utils +**************************************/ +int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; } +const char* LZ4_versionString(void) { return LZ4_VERSION_STRING; } +int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); } +int LZ4_sizeofState(void) { return sizeof(LZ4_stream_t); } + + +/*-**************************************** +* Internal Definitions, used only in Tests +*******************************************/ +#if defined (__cplusplus) +extern "C" { +#endif + +int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize); + +int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, + int compressedSize, int maxOutputSize, + const void* dictStart, size_t dictSize); +int LZ4_decompress_safe_partial_forceExtDict(const char* source, char* dest, + int compressedSize, int targetOutputSize, int dstCapacity, + const void* dictStart, size_t dictSize); +#if defined (__cplusplus) +} +#endif + +/*-****************************** +* Compression functions +********************************/ +LZ4_FORCE_INLINE U32 LZ4_hash4(U32 sequence, tableType_t const tableType) +{ + if (tableType == byU16) + return ((sequence * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1))); + else + return ((sequence * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG)); +} + +LZ4_FORCE_INLINE U32 LZ4_hash5(U64 sequence, tableType_t const tableType) +{ + const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG; + if (LZ4_isLittleEndian()) { + const U64 prime5bytes = 889523592379ULL; + return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog)); + } else { + const U64 prime8bytes = 11400714785074694791ULL; + return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog)); + } +} + +LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType) +{ + if ((sizeof(reg_t)==8) && (tableType != byU16)) return LZ4_hash5(LZ4_read_ARCH(p), tableType); + return LZ4_hash4(LZ4_read32(p), tableType); +} + +LZ4_FORCE_INLINE void LZ4_clearHash(U32 h, void* tableBase, tableType_t const tableType) +{ + switch (tableType) + { + default: /* fallthrough */ + case clearedTable: { /* illegal! */ assert(0); return; } + case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = NULL; return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = 0; return; } + case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = 0; return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putIndexOnHash(U32 idx, U32 h, void* tableBase, tableType_t const tableType) +{ + switch (tableType) + { + default: /* fallthrough */ + case clearedTable: /* fallthrough */ + case byPtr: { /* illegal! */ assert(0); return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = idx; return; } + case byU16: { U16* hashTable = (U16*) tableBase; assert(idx < 65536); hashTable[h] = (U16)idx; return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putPositionOnHash(const BYTE* p, U32 h, + void* tableBase, tableType_t const tableType, + const BYTE* srcBase) +{ + switch (tableType) + { + case clearedTable: { /* illegal! */ assert(0); return; } + case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; } + case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + U32 const h = LZ4_hashPosition(p, tableType); + LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase); +} + +/* LZ4_getIndexOnHash() : + * Index of match position registered in hash table. + * hash position must be calculated by using base+index, or dictBase+index. + * Assumption 1 : only valid if tableType == byU32 or byU16. + * Assumption 2 : h is presumed valid (within limits of hash table) + */ +LZ4_FORCE_INLINE U32 LZ4_getIndexOnHash(U32 h, const void* tableBase, tableType_t tableType) +{ + LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2); + if (tableType == byU32) { + const U32* const hashTable = (const U32*) tableBase; + assert(h < (1U << (LZ4_MEMORY_USAGE-2))); + return hashTable[h]; + } + if (tableType == byU16) { + const U16* const hashTable = (const U16*) tableBase; + assert(h < (1U << (LZ4_MEMORY_USAGE-1))); + return hashTable[h]; + } + assert(0); return 0; /* forbidden case */ +} + +static const BYTE* LZ4_getPositionOnHash(U32 h, const void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + if (tableType == byPtr) { const BYTE* const* hashTable = (const BYTE* const*) tableBase; return hashTable[h]; } + if (tableType == byU32) { const U32* const hashTable = (const U32*) tableBase; return hashTable[h] + srcBase; } + { const U16* const hashTable = (const U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */ +} + +LZ4_FORCE_INLINE const BYTE* +LZ4_getPosition(const BYTE* p, + const void* tableBase, tableType_t tableType, + const BYTE* srcBase) +{ + U32 const h = LZ4_hashPosition(p, tableType); + return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase); +} + +LZ4_FORCE_INLINE void +LZ4_prepareTable(LZ4_stream_t_internal* const cctx, + const int inputSize, + const tableType_t tableType) { + /* If the table hasn't been used, it's guaranteed to be zeroed out, and is + * therefore safe to use no matter what mode we're in. Otherwise, we figure + * out if it's safe to leave as is or whether it needs to be reset. + */ + if ((tableType_t)cctx->tableType != clearedTable) { + assert(inputSize >= 0); + if ((tableType_t)cctx->tableType != tableType + || ((tableType == byU16) && cctx->currentOffset + (unsigned)inputSize >= 0xFFFFU) + || ((tableType == byU32) && cctx->currentOffset > 1 GB) + || tableType == byPtr + || inputSize >= 4 KB) + { + DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx); + MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE); + cctx->currentOffset = 0; + cctx->tableType = (U32)clearedTable; + } else { + DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)"); + } + } + + /* Adding a gap, so all previous entries are > LZ4_DISTANCE_MAX back, + * is faster than compressing without a gap. + * However, compressing with currentOffset == 0 is faster still, + * so we preserve that case. + */ + if (cctx->currentOffset != 0 && tableType == byU32) { + DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset"); + cctx->currentOffset += 64 KB; + } + + /* Finally, clear history */ + cctx->dictCtx = NULL; + cctx->dictionary = NULL; + cctx->dictSize = 0; +} + +/** LZ4_compress_generic() : + * inlined, to ensure branches are decided at compilation time. + * Presumed already validated at this stage: + * - source != NULL + * - inputSize > 0 + */ +LZ4_FORCE_INLINE int LZ4_compress_generic_validated( + LZ4_stream_t_internal* const cctx, + const char* const source, + char* const dest, + const int inputSize, + int* inputConsumed, /* only written when outputDirective == fillOutput */ + const int maxOutputSize, + const limitedOutput_directive outputDirective, + const tableType_t tableType, + const dict_directive dictDirective, + const dictIssue_directive dictIssue, + const int acceleration) +{ + int result; + const BYTE* ip = (const BYTE*) source; + + U32 const startIndex = cctx->currentOffset; + const BYTE* base = (const BYTE*) source - startIndex; + const BYTE* lowLimit; + + const LZ4_stream_t_internal* dictCtx = (const LZ4_stream_t_internal*) cctx->dictCtx; + const BYTE* const dictionary = + dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary; + const U32 dictSize = + dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize; + const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */ + + int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx); + U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */ + const BYTE* const dictEnd = dictionary ? dictionary + dictSize : dictionary; + const BYTE* anchor = (const BYTE*) source; + const BYTE* const iend = ip + inputSize; + const BYTE* const mflimitPlusOne = iend - MFLIMIT + 1; + const BYTE* const matchlimit = iend - LASTLITERALS; + + /* the dictCtx currentOffset is indexed on the start of the dictionary, + * while a dictionary in the current context precedes the currentOffset */ + const BYTE* dictBase = (dictionary == NULL) ? NULL : + (dictDirective == usingDictCtx) ? + dictionary + dictSize - dictCtx->currentOffset : + dictionary + dictSize - startIndex; + + BYTE* op = (BYTE*) dest; + BYTE* const olimit = op + maxOutputSize; + + U32 offset = 0; + U32 forwardH; + + DEBUGLOG(5, "LZ4_compress_generic_validated: srcSize=%i, tableType=%u", inputSize, tableType); + assert(ip != NULL); + /* If init conditions are not met, we don't have to mark stream + * as having dirty context, since no action was taken yet */ + if (outputDirective == fillOutput && maxOutputSize < 1) { return 0; } /* Impossible to store anything */ + if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) { return 0; } /* Size too large (not within 64K limit) */ + if (tableType==byPtr) assert(dictDirective==noDict); /* only supported use case with byPtr */ + assert(acceleration >= 1); + + lowLimit = (const BYTE*)source - (dictDirective == withPrefix64k ? dictSize : 0); + + /* Update context state */ + if (dictDirective == usingDictCtx) { + /* Subsequent linked blocks can't use the dictionary. */ + /* Instead, they use the block we just compressed. */ + cctx->dictCtx = NULL; + cctx->dictSize = (U32)inputSize; + } else { + cctx->dictSize += (U32)inputSize; + } + cctx->currentOffset += (U32)inputSize; + cctx->tableType = (U32)tableType; + + if (inputSizehashTable, tableType, base); + ip++; forwardH = LZ4_hashPosition(ip, tableType); + + /* Main Loop */ + for ( ; ; ) { + const BYTE* match; + BYTE* token; + const BYTE* filledIp; + + /* Find a match */ + if (tableType == byPtr) { + const BYTE* forwardIp = ip; + int step = 1; + int searchMatchNb = acceleration << LZ4_skipTrigger; + do { + U32 const h = forwardH; + ip = forwardIp; + forwardIp += step; + step = (searchMatchNb++ >> LZ4_skipTrigger); + + if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; + assert(ip < mflimitPlusOne); + + match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base); + forwardH = LZ4_hashPosition(forwardIp, tableType); + LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base); + + } while ( (match+LZ4_DISTANCE_MAX < ip) + || (LZ4_read32(match) != LZ4_read32(ip)) ); + + } else { /* byU32, byU16 */ + + const BYTE* forwardIp = ip; + int step = 1; + int searchMatchNb = acceleration << LZ4_skipTrigger; + do { + U32 const h = forwardH; + U32 const current = (U32)(forwardIp - base); + U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); + assert(matchIndex <= current); + assert(forwardIp - base < (ptrdiff_t)(2 GB - 1)); + ip = forwardIp; + forwardIp += step; + step = (searchMatchNb++ >> LZ4_skipTrigger); + + if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; + assert(ip < mflimitPlusOne); + + if (dictDirective == usingDictCtx) { + if (matchIndex < startIndex) { + /* there was no match, try the dictionary */ + assert(tableType == byU32); + matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); + match = dictBase + matchIndex; + matchIndex += dictDelta; /* make dictCtx index comparable with current context */ + lowLimit = dictionary; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; + } + } else if (dictDirective == usingExtDict) { + if (matchIndex < startIndex) { + DEBUGLOG(7, "extDict candidate: matchIndex=%5u < startIndex=%5u", matchIndex, startIndex); + assert(startIndex - matchIndex >= MINMATCH); + assert(dictBase); + match = dictBase + matchIndex; + lowLimit = dictionary; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; + } + } else { /* single continuous memory segment */ + match = base + matchIndex; + } + forwardH = LZ4_hashPosition(forwardIp, tableType); + LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); + + DEBUGLOG(7, "candidate at pos=%u (offset=%u \n", matchIndex, current - matchIndex); + if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) { continue; } /* match outside of valid area */ + assert(matchIndex < current); + if ( ((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX)) + && (matchIndex+LZ4_DISTANCE_MAX < current)) { + continue; + } /* too far */ + assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */ + + if (LZ4_read32(match) == LZ4_read32(ip)) { + if (maybe_extMem) offset = current - matchIndex; + break; /* match found */ + } + + } while(1); + } + + /* Catch up */ + filledIp = ip; + while (((ip>anchor) & (match > lowLimit)) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; } + + /* Encode Literals */ + { unsigned const litLength = (unsigned)(ip - anchor); + token = op++; + if ((outputDirective == limitedOutput) && /* Check output buffer overflow */ + (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)) ) { + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + if ((outputDirective == fillOutput) && + (unlikely(op + (litLength+240)/255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))) { + op--; + goto _last_literals; + } + if (litLength >= RUN_MASK) { + int len = (int)(litLength - RUN_MASK); + *token = (RUN_MASK<= 255 ; len-=255) *op++ = 255; + *op++ = (BYTE)len; + } + else *token = (BYTE)(litLength< olimit)) { + /* the match was too close to the end, rewind and go to last literals */ + op = token; + goto _last_literals; + } + + /* Encode Offset */ + if (maybe_extMem) { /* static test */ + DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE*)source)); + assert(offset <= LZ4_DISTANCE_MAX && offset > 0); + LZ4_writeLE16(op, (U16)offset); op+=2; + } else { + DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match)); + assert(ip-match <= LZ4_DISTANCE_MAX); + LZ4_writeLE16(op, (U16)(ip - match)); op+=2; + } + + /* Encode MatchLength */ + { unsigned matchCode; + + if ( (dictDirective==usingExtDict || dictDirective==usingDictCtx) + && (lowLimit==dictionary) /* match within extDict */ ) { + const BYTE* limit = ip + (dictEnd-match); + assert(dictEnd > match); + if (limit > matchlimit) limit = matchlimit; + matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, limit); + ip += (size_t)matchCode + MINMATCH; + if (ip==limit) { + unsigned const more = LZ4_count(limit, (const BYTE*)source, matchlimit); + matchCode += more; + ip += more; + } + DEBUGLOG(6, " with matchLength=%u starting in extDict", matchCode+MINMATCH); + } else { + matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit); + ip += (size_t)matchCode + MINMATCH; + DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH); + } + + if ((outputDirective) && /* Check output buffer overflow */ + (unlikely(op + (1 + LASTLITERALS) + (matchCode+240)/255 > olimit)) ) { + if (outputDirective == fillOutput) { + /* Match description too long : reduce it */ + U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 1 - LASTLITERALS) * 255; + ip -= matchCode - newMatchCode; + assert(newMatchCode < matchCode); + matchCode = newMatchCode; + if (unlikely(ip <= filledIp)) { + /* We have already filled up to filledIp so if ip ends up less than filledIp + * we have positions in the hash table beyond the current position. This is + * a problem if we reuse the hash table. So we have to remove these positions + * from the hash table. + */ + const BYTE* ptr; + DEBUGLOG(5, "Clearing %u positions", (U32)(filledIp - ip)); + for (ptr = ip; ptr <= filledIp; ++ptr) { + U32 const h = LZ4_hashPosition(ptr, tableType); + LZ4_clearHash(h, cctx->hashTable, tableType); + } + } + } else { + assert(outputDirective == limitedOutput); + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + } + if (matchCode >= ML_MASK) { + *token += ML_MASK; + matchCode -= ML_MASK; + LZ4_write32(op, 0xFFFFFFFF); + while (matchCode >= 4*255) { + op+=4; + LZ4_write32(op, 0xFFFFFFFF); + matchCode -= 4*255; + } + op += matchCode / 255; + *op++ = (BYTE)(matchCode % 255); + } else + *token += (BYTE)(matchCode); + } + /* Ensure we have enough space for the last literals. */ + assert(!(outputDirective == fillOutput && op + 1 + LASTLITERALS > olimit)); + + anchor = ip; + + /* Test end of chunk */ + if (ip >= mflimitPlusOne) break; + + /* Fill table */ + LZ4_putPosition(ip-2, cctx->hashTable, tableType, base); + + /* Test next position */ + if (tableType == byPtr) { + + match = LZ4_getPosition(ip, cctx->hashTable, tableType, base); + LZ4_putPosition(ip, cctx->hashTable, tableType, base); + if ( (match+LZ4_DISTANCE_MAX >= ip) + && (LZ4_read32(match) == LZ4_read32(ip)) ) + { token=op++; *token=0; goto _next_match; } + + } else { /* byU32, byU16 */ + + U32 const h = LZ4_hashPosition(ip, tableType); + U32 const current = (U32)(ip-base); + U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); + assert(matchIndex < current); + if (dictDirective == usingDictCtx) { + if (matchIndex < startIndex) { + /* there was no match, try the dictionary */ + matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); + match = dictBase + matchIndex; + lowLimit = dictionary; /* required for match length counter */ + matchIndex += dictDelta; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; /* required for match length counter */ + } + } else if (dictDirective==usingExtDict) { + if (matchIndex < startIndex) { + assert(dictBase); + match = dictBase + matchIndex; + lowLimit = dictionary; /* required for match length counter */ + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; /* required for match length counter */ + } + } else { /* single memory segment */ + match = base + matchIndex; + } + LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); + assert(matchIndex < current); + if ( ((dictIssue==dictSmall) ? (matchIndex >= prefixIdxLimit) : 1) + && (((tableType==byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex+LZ4_DISTANCE_MAX >= current)) + && (LZ4_read32(match) == LZ4_read32(ip)) ) { + token=op++; + *token=0; + if (maybe_extMem) offset = current - matchIndex; + DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i", + (int)(anchor-(const BYTE*)source), 0, (int)(ip-(const BYTE*)source)); + goto _next_match; + } + } + + /* Prepare next loop */ + forwardH = LZ4_hashPosition(++ip, tableType); + + } + +_last_literals: + /* Encode Last Literals */ + { size_t lastRun = (size_t)(iend - anchor); + if ( (outputDirective) && /* Check output buffer overflow */ + (op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) { + if (outputDirective == fillOutput) { + /* adapt lastRun to fill 'dst' */ + assert(olimit >= op); + lastRun = (size_t)(olimit-op) - 1/*token*/; + lastRun -= (lastRun + 256 - RUN_MASK) / 256; /*additional length tokens*/ + } else { + assert(outputDirective == limitedOutput); + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + } + DEBUGLOG(6, "Final literal run : %i literals", (int)lastRun); + if (lastRun >= RUN_MASK) { + size_t accumulator = lastRun - RUN_MASK; + *op++ = RUN_MASK << ML_BITS; + for(; accumulator >= 255 ; accumulator-=255) *op++ = 255; + *op++ = (BYTE) accumulator; + } else { + *op++ = (BYTE)(lastRun< 0); + DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, result); + return result; +} + +/** LZ4_compress_generic() : + * inlined, to ensure branches are decided at compilation time; + * takes care of src == (NULL, 0) + * and forward the rest to LZ4_compress_generic_validated */ +LZ4_FORCE_INLINE int LZ4_compress_generic( + LZ4_stream_t_internal* const cctx, + const char* const src, + char* const dst, + const int srcSize, + int *inputConsumed, /* only written when outputDirective == fillOutput */ + const int dstCapacity, + const limitedOutput_directive outputDirective, + const tableType_t tableType, + const dict_directive dictDirective, + const dictIssue_directive dictIssue, + const int acceleration) +{ + DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, dstCapacity=%i", + srcSize, dstCapacity); + + if ((U32)srcSize > (U32)LZ4_MAX_INPUT_SIZE) { return 0; } /* Unsupported srcSize, too large (or negative) */ + if (srcSize == 0) { /* src == NULL supported if srcSize == 0 */ + if (outputDirective != notLimited && dstCapacity <= 0) return 0; /* no output, can't write anything */ + DEBUGLOG(5, "Generating an empty block"); + assert(outputDirective == notLimited || dstCapacity >= 1); + assert(dst != NULL); + dst[0] = 0; + if (outputDirective == fillOutput) { + assert (inputConsumed != NULL); + *inputConsumed = 0; + } + return 1; + } + assert(src != NULL); + + return LZ4_compress_generic_validated(cctx, src, dst, srcSize, + inputConsumed, /* only written into if outputDirective == fillOutput */ + dstCapacity, outputDirective, + tableType, dictDirective, dictIssue, acceleration); +} + + +int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) +{ + LZ4_stream_t_internal* const ctx = & LZ4_initStream(state, sizeof(LZ4_stream_t)) -> internal_donotuse; + assert(ctx != NULL); + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + if (maxOutputSize >= LZ4_compressBound(inputSize)) { + if (inputSize < LZ4_64Klimit) { + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration); + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + if (inputSize < LZ4_64Klimit) { + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration); + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } +} + +/** + * LZ4_compress_fast_extState_fastReset() : + * A variant of LZ4_compress_fast_extState(). + * + * Using this variant avoids an expensive initialization step. It is only safe + * to call if the state buffer is known to be correctly initialized already + * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of + * "correctly initialized"). + */ +int LZ4_compress_fast_extState_fastReset(void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration) +{ + LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse; + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + + if (dstCapacity >= LZ4_compressBound(srcSize)) { + if (srcSize < LZ4_64Klimit) { + const tableType_t tableType = byU16; + LZ4_prepareTable(ctx, srcSize, tableType); + if (ctx->currentOffset) { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration); + } else { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + LZ4_prepareTable(ctx, srcSize, tableType); + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + if (srcSize < LZ4_64Klimit) { + const tableType_t tableType = byU16; + LZ4_prepareTable(ctx, srcSize, tableType); + if (ctx->currentOffset) { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration); + } else { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + LZ4_prepareTable(ctx, srcSize, tableType); + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } +} + + +int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) +{ + int result; +#if (LZ4_HEAPMODE) + LZ4_stream_t* ctxPtr = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ + if (ctxPtr == NULL) return 0; +#else + LZ4_stream_t ctx; + LZ4_stream_t* const ctxPtr = &ctx; +#endif + result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration); + +#if (LZ4_HEAPMODE) + FREEMEM(ctxPtr); +#endif + return result; +} + + +int LZ4_compress_default(const char* src, char* dst, int srcSize, int maxOutputSize) +{ + return LZ4_compress_fast(src, dst, srcSize, maxOutputSize, 1); +} + + +/* Note!: This function leaves the stream in an unclean/broken state! + * It is not safe to subsequently use the same state with a _fastReset() or + * _continue() call without resetting it. */ +static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize) +{ + void* const s = LZ4_initStream(state, sizeof (*state)); + assert(s != NULL); (void)s; + + if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) { /* compression success is guaranteed */ + return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1); + } else { + if (*srcSizePtr < LZ4_64Klimit) { + return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1); + } else { + tableType_t const addrMode = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, addrMode, noDict, noDictIssue, 1); + } } +} + + +int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize) +{ +#if (LZ4_HEAPMODE) + LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ + if (ctx == NULL) return 0; +#else + LZ4_stream_t ctxBody; + LZ4_stream_t* ctx = &ctxBody; +#endif + + int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize); + +#if (LZ4_HEAPMODE) + FREEMEM(ctx); +#endif + return result; +} + + + +/*-****************************** +* Streaming functions +********************************/ + +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) +LZ4_stream_t* LZ4_createStream(void) +{ + LZ4_stream_t* const lz4s = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); + LZ4_STATIC_ASSERT(sizeof(LZ4_stream_t) >= sizeof(LZ4_stream_t_internal)); + DEBUGLOG(4, "LZ4_createStream %p", lz4s); + if (lz4s == NULL) return NULL; + LZ4_initStream(lz4s, sizeof(*lz4s)); + return lz4s; +} +#endif + +static size_t LZ4_stream_t_alignment(void) +{ +#if LZ4_ALIGN_TEST + typedef struct { char c; LZ4_stream_t t; } t_a; + return sizeof(t_a) - sizeof(LZ4_stream_t); +#else + return 1; /* effectively disabled */ +#endif +} + +LZ4_stream_t* LZ4_initStream (void* buffer, size_t size) +{ + DEBUGLOG(5, "LZ4_initStream"); + if (buffer == NULL) { return NULL; } + if (size < sizeof(LZ4_stream_t)) { return NULL; } + if (!LZ4_isAligned(buffer, LZ4_stream_t_alignment())) return NULL; + MEM_INIT(buffer, 0, sizeof(LZ4_stream_t_internal)); + return (LZ4_stream_t*)buffer; +} + +/* resetStream is now deprecated, + * prefer initStream() which is more general */ +void LZ4_resetStream (LZ4_stream_t* LZ4_stream) +{ + DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream); + MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t_internal)); +} + +void LZ4_resetStream_fast(LZ4_stream_t* ctx) { + LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32); +} + +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) +int LZ4_freeStream (LZ4_stream_t* LZ4_stream) +{ + if (!LZ4_stream) return 0; /* support free on NULL */ + DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream); + FREEMEM(LZ4_stream); + return (0); +} +#endif + + +#define HASH_UNIT sizeof(reg_t) +int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize) +{ + LZ4_stream_t_internal* dict = &LZ4_dict->internal_donotuse; + const tableType_t tableType = byU32; + const BYTE* p = (const BYTE*)dictionary; + const BYTE* const dictEnd = p + dictSize; + const BYTE* base; + + DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict); + + /* It's necessary to reset the context, + * and not just continue it with prepareTable() + * to avoid any risk of generating overflowing matchIndex + * when compressing using this dictionary */ + LZ4_resetStream(LZ4_dict); + + /* We always increment the offset by 64 KB, since, if the dict is longer, + * we truncate it to the last 64k, and if it's shorter, we still want to + * advance by a whole window length so we can provide the guarantee that + * there are only valid offsets in the window, which allows an optimization + * in LZ4_compress_fast_continue() where it uses noDictIssue even when the + * dictionary isn't a full 64k. */ + dict->currentOffset += 64 KB; + + if (dictSize < (int)HASH_UNIT) { + return 0; + } + + if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB; + base = dictEnd - dict->currentOffset; + dict->dictionary = p; + dict->dictSize = (U32)(dictEnd - p); + dict->tableType = (U32)tableType; + + while (p <= dictEnd-HASH_UNIT) { + LZ4_putPosition(p, dict->hashTable, tableType, base); + p+=3; + } + + return (int)dict->dictSize; +} + +void LZ4_attach_dictionary(LZ4_stream_t* workingStream, const LZ4_stream_t* dictionaryStream) +{ + const LZ4_stream_t_internal* dictCtx = (dictionaryStream == NULL) ? NULL : + &(dictionaryStream->internal_donotuse); + + DEBUGLOG(4, "LZ4_attach_dictionary (%p, %p, size %u)", + workingStream, dictionaryStream, + dictCtx != NULL ? dictCtx->dictSize : 0); + + if (dictCtx != NULL) { + /* If the current offset is zero, we will never look in the + * external dictionary context, since there is no value a table + * entry can take that indicate a miss. In that case, we need + * to bump the offset to something non-zero. + */ + if (workingStream->internal_donotuse.currentOffset == 0) { + workingStream->internal_donotuse.currentOffset = 64 KB; + } + + /* Don't actually attach an empty dictionary. + */ + if (dictCtx->dictSize == 0) { + dictCtx = NULL; + } + } + workingStream->internal_donotuse.dictCtx = dictCtx; +} + + +static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, int nextSize) +{ + assert(nextSize >= 0); + if (LZ4_dict->currentOffset + (unsigned)nextSize > 0x80000000) { /* potential ptrdiff_t overflow (32-bits mode) */ + /* rescale hash table */ + U32 const delta = LZ4_dict->currentOffset - 64 KB; + const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize; + int i; + DEBUGLOG(4, "LZ4_renormDictT"); + for (i=0; ihashTable[i] < delta) LZ4_dict->hashTable[i]=0; + else LZ4_dict->hashTable[i] -= delta; + } + LZ4_dict->currentOffset = 64 KB; + if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB; + LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize; + } +} + + +int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, + const char* source, char* dest, + int inputSize, int maxOutputSize, + int acceleration) +{ + const tableType_t tableType = byU32; + LZ4_stream_t_internal* const streamPtr = &LZ4_stream->internal_donotuse; + const char* dictEnd = streamPtr->dictSize ? (const char*)streamPtr->dictionary + streamPtr->dictSize : NULL; + + DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i, dictSize=%u)", inputSize, streamPtr->dictSize); + + LZ4_renormDictT(streamPtr, inputSize); /* fix index overflow */ + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + + /* invalidate tiny dictionaries */ + if ( (streamPtr->dictSize < 4) /* tiny dictionary : not enough for a hash */ + && (dictEnd != source) /* prefix mode */ + && (inputSize > 0) /* tolerance : don't lose history, in case next invocation would use prefix mode */ + && (streamPtr->dictCtx == NULL) /* usingDictCtx */ + ) { + DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary); + /* remove dictionary existence from history, to employ faster prefix mode */ + streamPtr->dictSize = 0; + streamPtr->dictionary = (const BYTE*)source; + dictEnd = source; + } + + /* Check overlapping input/dictionary space */ + { const char* const sourceEnd = source + inputSize; + if ((sourceEnd > (const char*)streamPtr->dictionary) && (sourceEnd < dictEnd)) { + streamPtr->dictSize = (U32)(dictEnd - sourceEnd); + if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB; + if (streamPtr->dictSize < 4) streamPtr->dictSize = 0; + streamPtr->dictionary = (const BYTE*)dictEnd - streamPtr->dictSize; + } + } + + /* prefix mode : source data follows dictionary */ + if (dictEnd == source) { + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) + return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration); + else + return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration); + } + + /* external dictionary mode */ + { int result; + if (streamPtr->dictCtx) { + /* We depend here on the fact that dictCtx'es (produced by + * LZ4_loadDict) guarantee that their tables contain no references + * to offsets between dictCtx->currentOffset - 64 KB and + * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe + * to use noDictIssue even when the dict isn't a full 64 KB. + */ + if (inputSize > 4 KB) { + /* For compressing large blobs, it is faster to pay the setup + * cost to copy the dictionary's tables into the active context, + * so that the compression loop is only looking into one table. + */ + LZ4_memcpy(streamPtr, streamPtr->dictCtx, sizeof(*streamPtr)); + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration); + } + } else { /* small data <= 4 KB */ + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); + } + } + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)inputSize; + return result; + } +} + + +/* Hidden debug function, to force-test external dictionary mode */ +int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize) +{ + LZ4_stream_t_internal* streamPtr = &LZ4_dict->internal_donotuse; + int result; + + LZ4_renormDictT(streamPtr, srcSize); + + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { + result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1); + } + + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)srcSize; + + return result; +} + + +/*! LZ4_saveDict() : + * If previously compressed data block is not guaranteed to remain available at its memory location, + * save it into a safer place (char* safeBuffer). + * Note : no need to call LZ4_loadDict() afterwards, dictionary is immediately usable, + * one can therefore call LZ4_compress_fast_continue() right after. + * @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. + */ +int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize) +{ + LZ4_stream_t_internal* const dict = &LZ4_dict->internal_donotuse; + + DEBUGLOG(5, "LZ4_saveDict : dictSize=%i, safeBuffer=%p", dictSize, safeBuffer); + + if ((U32)dictSize > 64 KB) { dictSize = 64 KB; } /* useless to define a dictionary > 64 KB */ + if ((U32)dictSize > dict->dictSize) { dictSize = (int)dict->dictSize; } + + if (safeBuffer == NULL) assert(dictSize == 0); + if (dictSize > 0) { + const BYTE* const previousDictEnd = dict->dictionary + dict->dictSize; + assert(dict->dictionary); + LZ4_memmove(safeBuffer, previousDictEnd - dictSize, (size_t)dictSize); + } + + dict->dictionary = (const BYTE*)safeBuffer; + dict->dictSize = (U32)dictSize; + + return dictSize; +} + + + +/*-******************************* + * Decompression functions + ********************************/ + +typedef enum { decode_full_block = 0, partial_decode = 1 } earlyEnd_directive; + +#undef MIN +#define MIN(a,b) ( (a) < (b) ? (a) : (b) ) + + +/* variant for decompress_unsafe() + * does not know end of input + * presumes input is well formed + * note : will consume at least one byte */ +size_t read_long_length_no_check(const BYTE** pp) +{ + size_t b, l = 0; + do { b = **pp; (*pp)++; l += b; } while (b==255); + DEBUGLOG(6, "read_long_length_no_check: +length=%zu using %zu input bytes", l, l/255 + 1) + return l; +} + +/* core decoder variant for LZ4_decompress_fast*() + * for legacy support only : these entry points are deprecated. + * - Presumes input is correctly formed (no defense vs malformed inputs) + * - Does not know input size (presume input buffer is "large enough") + * - Decompress a full block (only) + * @return : nb of bytes read from input. + * Note : this variant is not optimized for speed, just for maintenance. + * the goal is to remove support of decompress_fast*() variants by v2.0 +**/ +LZ4_FORCE_INLINE int +LZ4_decompress_unsafe_generic( + const BYTE* const istart, + BYTE* const ostart, + int decompressedSize, + + size_t prefixSize, + const BYTE* const dictStart, /* only if dict==usingExtDict */ + const size_t dictSize /* note: =0 if dictStart==NULL */ + ) +{ + const BYTE* ip = istart; + BYTE* op = (BYTE*)ostart; + BYTE* const oend = ostart + decompressedSize; + const BYTE* const prefixStart = ostart - prefixSize; + + DEBUGLOG(5, "LZ4_decompress_unsafe_generic"); + if (dictStart == NULL) assert(dictSize == 0); + + while (1) { + /* start new sequence */ + unsigned token = *ip++; + + /* literals */ + { size_t ll = token >> ML_BITS; + if (ll==15) { + /* long literal length */ + ll += read_long_length_no_check(&ip); + } + if ((size_t)(oend-op) < ll) return -1; /* output buffer overflow */ + LZ4_memmove(op, ip, ll); /* support in-place decompression */ + op += ll; + ip += ll; + if ((size_t)(oend-op) < MFLIMIT) { + if (op==oend) break; /* end of block */ + DEBUGLOG(5, "invalid: literals end at distance %zi from end of block", oend-op); + /* incorrect end of block : + * last match must start at least MFLIMIT==12 bytes before end of output block */ + return -1; + } } + + /* match */ + { size_t ml = token & 15; + size_t const offset = LZ4_readLE16(ip); + ip+=2; + + if (ml==15) { + /* long literal length */ + ml += read_long_length_no_check(&ip); + } + ml += MINMATCH; + + if ((size_t)(oend-op) < ml) return -1; /* output buffer overflow */ + + { const BYTE* match = op - offset; + + /* out of range */ + if (offset > (size_t)(op - prefixStart) + dictSize) { + DEBUGLOG(6, "offset out of range"); + return -1; + } + + /* check special case : extDict */ + if (offset > (size_t)(op - prefixStart)) { + /* extDict scenario */ + const BYTE* const dictEnd = dictStart + dictSize; + const BYTE* extMatch = dictEnd - (offset - (size_t)(op-prefixStart)); + size_t const extml = (size_t)(dictEnd - extMatch); + if (extml > ml) { + /* match entirely within extDict */ + LZ4_memmove(op, extMatch, ml); + op += ml; + ml = 0; + } else { + /* match split between extDict & prefix */ + LZ4_memmove(op, extMatch, extml); + op += extml; + ml -= extml; + } + match = prefixStart; + } + + /* match copy - slow variant, supporting overlap copy */ + { size_t u; + for (u=0; u= ipmax before start of loop. Returns initial_error if so. + * @error (output) - error code. Must be set to 0 before call. +**/ +typedef size_t Rvl_t; +static const Rvl_t rvl_error = (Rvl_t)(-1); +LZ4_FORCE_INLINE Rvl_t +read_variable_length(const BYTE** ip, const BYTE* ilimit, + int initial_check) +{ + Rvl_t s, length = 0; + assert(ip != NULL); + assert(*ip != NULL); + assert(ilimit != NULL); + if (initial_check && unlikely((*ip) >= ilimit)) { /* read limit reached */ + return rvl_error; + } + do { + s = **ip; + (*ip)++; + length += s; + if (unlikely((*ip) > ilimit)) { /* read limit reached */ + return rvl_error; + } + /* accumulator overflow detection (32-bit mode only) */ + if ((sizeof(length)<8) && unlikely(length > ((Rvl_t)(-1)/2)) ) { + return rvl_error; + } + } while (s==255); + + return length; +} + +/*! LZ4_decompress_generic() : + * This generic decompression function covers all use cases. + * It shall be instantiated several times, using different sets of directives. + * Note that it is important for performance that this function really get inlined, + * in order to remove useless branches during compilation optimization. + */ +LZ4_FORCE_INLINE int +LZ4_decompress_generic( + const char* const src, + char* const dst, + int srcSize, + int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */ + + earlyEnd_directive partialDecoding, /* full, partial */ + dict_directive dict, /* noDict, withPrefix64k, usingExtDict */ + const BYTE* const lowPrefix, /* always <= dst, == dst when no prefix */ + const BYTE* const dictStart, /* only if dict==usingExtDict */ + const size_t dictSize /* note : = 0 if noDict */ + ) +{ + if ((src == NULL) || (outputSize < 0)) { return -1; } + + { const BYTE* ip = (const BYTE*) src; + const BYTE* const iend = ip + srcSize; + + BYTE* op = (BYTE*) dst; + BYTE* const oend = op + outputSize; + BYTE* cpy; + + const BYTE* const dictEnd = (dictStart == NULL) ? NULL : dictStart + dictSize; + + const int checkOffset = (dictSize < (int)(64 KB)); + + + /* Set up the "end" pointers for the shortcut. */ + const BYTE* const shortiend = iend - 14 /*maxLL*/ - 2 /*offset*/; + const BYTE* const shortoend = oend - 14 /*maxLL*/ - 18 /*maxML*/; + + const BYTE* match; + size_t offset; + unsigned token; + size_t length; + + + DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize); + + /* Special cases */ + assert(lowPrefix <= op); + if (unlikely(outputSize==0)) { + /* Empty output buffer */ + if (partialDecoding) return 0; + return ((srcSize==1) && (*ip==0)) ? 0 : -1; + } + if (unlikely(srcSize==0)) { return -1; } + + /* LZ4_FAST_DEC_LOOP: + * designed for modern OoO performance cpus, + * where copying reliably 32-bytes is preferable to an unpredictable branch. + * note : fast loop may show a regression for some client arm chips. */ +#if LZ4_FAST_DEC_LOOP + if ((oend - op) < FASTLOOP_SAFE_DISTANCE) { + DEBUGLOG(6, "skip fast decode loop"); + goto safe_decode; + } + + /* Fast loop : decode sequences as long as output < oend-FASTLOOP_SAFE_DISTANCE */ + while (1) { + /* Main fastloop assertion: We can always wildcopy FASTLOOP_SAFE_DISTANCE */ + assert(oend - op >= FASTLOOP_SAFE_DISTANCE); + assert(ip < iend); + token = *ip++; + length = token >> ML_BITS; /* literal length */ + + /* decode literal length */ + if (length == RUN_MASK) { + size_t const addl = read_variable_length(&ip, iend-RUN_MASK, 1); + if (addl == rvl_error) { goto _output_error; } + length += addl; + if (unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ + if (unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ + + /* copy literals */ + cpy = op+length; + LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); + if ((cpy>oend-32) || (ip+length>iend-32)) { goto safe_literal_copy; } + LZ4_wildCopy32(op, ip, cpy); + ip += length; op = cpy; + } else { + cpy = op+length; + DEBUGLOG(7, "copy %u bytes in a 16-bytes stripe", (unsigned)length); + /* We don't need to check oend, since we check it once for each loop below */ + if (ip > iend-(16 + 1/*max lit + offset + nextToken*/)) { goto safe_literal_copy; } + /* Literals can only be <= 14, but hope compilers optimize better when copy by a register size */ + LZ4_memcpy(op, ip, 16); + ip += length; op = cpy; + } + + /* get offset */ + offset = LZ4_readLE16(ip); ip+=2; + match = op - offset; + assert(match <= op); /* overflow check */ + + /* get matchlength */ + length = token & ML_MASK; + + if (length == ML_MASK) { + size_t const addl = read_variable_length(&ip, iend - LASTLITERALS + 1, 0); + if (addl == rvl_error) { goto _output_error; } + length += addl; + length += MINMATCH; + if (unlikely((uptrval)(op)+length<(uptrval)op)) { goto _output_error; } /* overflow detection */ + if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ + if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { + goto safe_match_copy; + } + } else { + length += MINMATCH; + if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { + goto safe_match_copy; + } + + /* Fastpath check: skip LZ4_wildCopy32 when true */ + if ((dict == withPrefix64k) || (match >= lowPrefix)) { + if (offset >= 8) { + assert(match >= lowPrefix); + assert(match <= op); + assert(op + 18 <= oend); + + LZ4_memcpy(op, match, 8); + LZ4_memcpy(op+8, match+8, 8); + LZ4_memcpy(op+16, match+16, 2); + op += length; + continue; + } } } + + if (checkOffset && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ + /* match starting within external dictionary */ + if ((dict==usingExtDict) && (match < lowPrefix)) { + assert(dictEnd != NULL); + if (unlikely(op+length > oend-LASTLITERALS)) { + if (partialDecoding) { + DEBUGLOG(7, "partialDecoding: dictionary match, close to dstEnd"); + length = MIN(length, (size_t)(oend-op)); + } else { + goto _output_error; /* end-of-block condition violated */ + } } + + if (length <= (size_t)(lowPrefix-match)) { + /* match fits entirely within external dictionary : just copy */ + LZ4_memmove(op, dictEnd - (lowPrefix-match), length); + op += length; + } else { + /* match stretches into both external dictionary and current block */ + size_t const copySize = (size_t)(lowPrefix - match); + size_t const restSize = length - copySize; + LZ4_memcpy(op, dictEnd - copySize, copySize); + op += copySize; + if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ + BYTE* const endOfMatch = op + restSize; + const BYTE* copyFrom = lowPrefix; + while (op < endOfMatch) { *op++ = *copyFrom++; } + } else { + LZ4_memcpy(op, lowPrefix, restSize); + op += restSize; + } } + continue; + } + + /* copy match within block */ + cpy = op + length; + + assert((op <= oend) && (oend-op >= 32)); + if (unlikely(offset<16)) { + LZ4_memcpy_using_offset(op, match, cpy, offset); + } else { + LZ4_wildCopy32(op, match, cpy); + } + + op = cpy; /* wildcopy correction */ + } + safe_decode: +#endif + + /* Main Loop : decode remaining sequences where output < FASTLOOP_SAFE_DISTANCE */ + while (1) { + assert(ip < iend); + token = *ip++; + length = token >> ML_BITS; /* literal length */ + + /* A two-stage shortcut for the most common case: + * 1) If the literal length is 0..14, and there is enough space, + * enter the shortcut and copy 16 bytes on behalf of the literals + * (in the fast mode, only 8 bytes can be safely copied this way). + * 2) Further if the match length is 4..18, copy 18 bytes in a similar + * manner; but we ensure that there's enough space in the output for + * those 18 bytes earlier, upon entering the shortcut (in other words, + * there is a combined check for both stages). + */ + if ( (length != RUN_MASK) + /* strictly "less than" on input, to re-enter the loop with at least one byte */ + && likely((ip < shortiend) & (op <= shortoend)) ) { + /* Copy the literals */ + LZ4_memcpy(op, ip, 16); + op += length; ip += length; + + /* The second stage: prepare for match copying, decode full info. + * If it doesn't work out, the info won't be wasted. */ + length = token & ML_MASK; /* match length */ + offset = LZ4_readLE16(ip); ip += 2; + match = op - offset; + assert(match <= op); /* check overflow */ + + /* Do not deal with overlapping matches. */ + if ( (length != ML_MASK) + && (offset >= 8) + && (dict==withPrefix64k || match >= lowPrefix) ) { + /* Copy the match. */ + LZ4_memcpy(op + 0, match + 0, 8); + LZ4_memcpy(op + 8, match + 8, 8); + LZ4_memcpy(op +16, match +16, 2); + op += length + MINMATCH; + /* Both stages worked, load the next token. */ + continue; + } + + /* The second stage didn't work out, but the info is ready. + * Propel it right to the point of match copying. */ + goto _copy_match; + } + + /* decode literal length */ + if (length == RUN_MASK) { + size_t const addl = read_variable_length(&ip, iend-RUN_MASK, 1); + if (addl == rvl_error) { goto _output_error; } + length += addl; + if (unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ + if (unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ + } + + /* copy literals */ + cpy = op+length; +#if LZ4_FAST_DEC_LOOP + safe_literal_copy: +#endif + LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); + if ((cpy>oend-MFLIMIT) || (ip+length>iend-(2+1+LASTLITERALS))) { + /* We've either hit the input parsing restriction or the output parsing restriction. + * In the normal scenario, decoding a full block, it must be the last sequence, + * otherwise it's an error (invalid input or dimensions). + * In partialDecoding scenario, it's necessary to ensure there is no buffer overflow. + */ + if (partialDecoding) { + /* Since we are partial decoding we may be in this block because of the output parsing + * restriction, which is not valid since the output buffer is allowed to be undersized. + */ + DEBUGLOG(7, "partialDecoding: copying literals, close to input or output end") + DEBUGLOG(7, "partialDecoding: literal length = %u", (unsigned)length); + DEBUGLOG(7, "partialDecoding: remaining space in dstBuffer : %i", (int)(oend - op)); + DEBUGLOG(7, "partialDecoding: remaining space in srcBuffer : %i", (int)(iend - ip)); + /* Finishing in the middle of a literals segment, + * due to lack of input. + */ + if (ip+length > iend) { + length = (size_t)(iend-ip); + cpy = op + length; + } + /* Finishing in the middle of a literals segment, + * due to lack of output space. + */ + if (cpy > oend) { + cpy = oend; + assert(op<=oend); + length = (size_t)(oend-op); + } + } else { + /* We must be on the last sequence (or invalid) because of the parsing limitations + * so check that we exactly consume the input and don't overrun the output buffer. + */ + if ((ip+length != iend) || (cpy > oend)) { + DEBUGLOG(6, "should have been last run of literals") + DEBUGLOG(6, "ip(%p) + length(%i) = %p != iend (%p)", ip, (int)length, ip+length, iend); + DEBUGLOG(6, "or cpy(%p) > oend(%p)", cpy, oend); + goto _output_error; + } + } + LZ4_memmove(op, ip, length); /* supports overlapping memory regions, for in-place decompression scenarios */ + ip += length; + op += length; + /* Necessarily EOF when !partialDecoding. + * When partialDecoding, it is EOF if we've either + * filled the output buffer or + * can't proceed with reading an offset for following match. + */ + if (!partialDecoding || (cpy == oend) || (ip >= (iend-2))) { + break; + } + } else { + LZ4_wildCopy8(op, ip, cpy); /* can overwrite up to 8 bytes beyond cpy */ + ip += length; op = cpy; + } + + /* get offset */ + offset = LZ4_readLE16(ip); ip+=2; + match = op - offset; + + /* get matchlength */ + length = token & ML_MASK; + + _copy_match: + if (length == ML_MASK) { + size_t const addl = read_variable_length(&ip, iend - LASTLITERALS + 1, 0); + if (addl == rvl_error) { goto _output_error; } + length += addl; + if (unlikely((uptrval)(op)+length<(uptrval)op)) goto _output_error; /* overflow detection */ + } + length += MINMATCH; + +#if LZ4_FAST_DEC_LOOP + safe_match_copy: +#endif + if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) goto _output_error; /* Error : offset outside buffers */ + /* match starting within external dictionary */ + if ((dict==usingExtDict) && (match < lowPrefix)) { + assert(dictEnd != NULL); + if (unlikely(op+length > oend-LASTLITERALS)) { + if (partialDecoding) length = MIN(length, (size_t)(oend-op)); + else goto _output_error; /* doesn't respect parsing restriction */ + } + + if (length <= (size_t)(lowPrefix-match)) { + /* match fits entirely within external dictionary : just copy */ + LZ4_memmove(op, dictEnd - (lowPrefix-match), length); + op += length; + } else { + /* match stretches into both external dictionary and current block */ + size_t const copySize = (size_t)(lowPrefix - match); + size_t const restSize = length - copySize; + LZ4_memcpy(op, dictEnd - copySize, copySize); + op += copySize; + if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ + BYTE* const endOfMatch = op + restSize; + const BYTE* copyFrom = lowPrefix; + while (op < endOfMatch) *op++ = *copyFrom++; + } else { + LZ4_memcpy(op, lowPrefix, restSize); + op += restSize; + } } + continue; + } + assert(match >= lowPrefix); + + /* copy match within block */ + cpy = op + length; + + /* partialDecoding : may end anywhere within the block */ + assert(op<=oend); + if (partialDecoding && (cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { + size_t const mlen = MIN(length, (size_t)(oend-op)); + const BYTE* const matchEnd = match + mlen; + BYTE* const copyEnd = op + mlen; + if (matchEnd > op) { /* overlap copy */ + while (op < copyEnd) { *op++ = *match++; } + } else { + LZ4_memcpy(op, match, mlen); + } + op = copyEnd; + if (op == oend) { break; } + continue; + } + + if (unlikely(offset<8)) { + LZ4_write32(op, 0); /* silence msan warning when offset==0 */ + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += inc32table[offset]; + LZ4_memcpy(op+4, match, 4); + match -= dec64table[offset]; + } else { + LZ4_memcpy(op, match, 8); + match += 8; + } + op += 8; + + if (unlikely(cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { + BYTE* const oCopyLimit = oend - (WILDCOPYLENGTH-1); + if (cpy > oend-LASTLITERALS) { goto _output_error; } /* Error : last LASTLITERALS bytes must be literals (uncompressed) */ + if (op < oCopyLimit) { + LZ4_wildCopy8(op, match, oCopyLimit); + match += oCopyLimit - op; + op = oCopyLimit; + } + while (op < cpy) { *op++ = *match++; } + } else { + LZ4_memcpy(op, match, 8); + if (length > 16) { LZ4_wildCopy8(op+8, match+8, cpy); } + } + op = cpy; /* wildcopy correction */ + } + + /* end of decoding */ + DEBUGLOG(5, "decoded %i bytes", (int) (((char*)op)-dst)); + return (int) (((char*)op)-dst); /* Nb of output bytes decoded */ + + /* Overflow error detected */ + _output_error: + return (int) (-(((const char*)ip)-src))-1; + } +} + + +/*===== Instantiate the API decoding functions. =====*/ + +LZ4_FORCE_O2 +int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, + decode_full_block, noDict, + (BYTE*)dest, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_safe_partial(const char* src, char* dst, int compressedSize, int targetOutputSize, int dstCapacity) +{ + dstCapacity = MIN(targetOutputSize, dstCapacity); + return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity, + partial_decode, + noDict, (BYTE*)dst, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_fast(const char* source, char* dest, int originalSize) +{ + DEBUGLOG(5, "LZ4_decompress_fast"); + return LZ4_decompress_unsafe_generic( + (const BYTE*)source, (BYTE*)dest, originalSize, + 0, NULL, 0); +} + +/*===== Instantiate a few more decoding cases, used more than once. =====*/ + +LZ4_FORCE_O2 /* Exported, an obsolete API function. */ +int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + decode_full_block, withPrefix64k, + (BYTE*)dest - 64 KB, NULL, 0); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_safe_partial_withPrefix64k(const char* source, char* dest, int compressedSize, int targetOutputSize, int dstCapacity) +{ + dstCapacity = MIN(targetOutputSize, dstCapacity); + return LZ4_decompress_generic(source, dest, compressedSize, dstCapacity, + partial_decode, withPrefix64k, + (BYTE*)dest - 64 KB, NULL, 0); +} + +/* Another obsolete API function, paired with the previous one. */ +int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize) +{ + return LZ4_decompress_unsafe_generic( + (const BYTE*)source, (BYTE*)dest, originalSize, + 64 KB, NULL, 0); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_safe_withSmallPrefix(const char* source, char* dest, int compressedSize, int maxOutputSize, + size_t prefixSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + decode_full_block, noDict, + (BYTE*)dest-prefixSize, NULL, 0); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_safe_partial_withSmallPrefix(const char* source, char* dest, int compressedSize, int targetOutputSize, int dstCapacity, + size_t prefixSize) +{ + dstCapacity = MIN(targetOutputSize, dstCapacity); + return LZ4_decompress_generic(source, dest, compressedSize, dstCapacity, + partial_decode, noDict, + (BYTE*)dest-prefixSize, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, + int compressedSize, int maxOutputSize, + const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + decode_full_block, usingExtDict, + (BYTE*)dest, (const BYTE*)dictStart, dictSize); +} + +LZ4_FORCE_O2 +int LZ4_decompress_safe_partial_forceExtDict(const char* source, char* dest, + int compressedSize, int targetOutputSize, int dstCapacity, + const void* dictStart, size_t dictSize) +{ + dstCapacity = MIN(targetOutputSize, dstCapacity); + return LZ4_decompress_generic(source, dest, compressedSize, dstCapacity, + partial_decode, usingExtDict, + (BYTE*)dest, (const BYTE*)dictStart, dictSize); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_fast_extDict(const char* source, char* dest, int originalSize, + const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_unsafe_generic( + (const BYTE*)source, (BYTE*)dest, originalSize, + 0, (const BYTE*)dictStart, dictSize); +} + +/* The "double dictionary" mode, for use with e.g. ring buffers: the first part + * of the dictionary is passed as prefix, and the second via dictStart + dictSize. + * These routines are used only once, in LZ4_decompress_*_continue(). + */ +LZ4_FORCE_INLINE +int LZ4_decompress_safe_doubleDict(const char* source, char* dest, int compressedSize, int maxOutputSize, + size_t prefixSize, const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + decode_full_block, usingExtDict, + (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize); +} + +/*===== streaming decompression functions =====*/ + +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) +LZ4_streamDecode_t* LZ4_createStreamDecode(void) +{ + LZ4_STATIC_ASSERT(sizeof(LZ4_streamDecode_t) >= sizeof(LZ4_streamDecode_t_internal)); + return (LZ4_streamDecode_t*) ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t)); +} + +int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream) +{ + if (LZ4_stream == NULL) { return 0; } /* support free on NULL */ + FREEMEM(LZ4_stream); + return 0; +} +#endif + +/*! LZ4_setStreamDecode() : + * Use this function to instruct where to find the dictionary. + * This function is not necessary if previous data is still available where it was decoded. + * Loading a size of 0 is allowed (same effect as no dictionary). + * @return : 1 if OK, 0 if error + */ +int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize) +{ + LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; + lz4sd->prefixSize = (size_t)dictSize; + if (dictSize) { + assert(dictionary != NULL); + lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize; + } else { + lz4sd->prefixEnd = (const BYTE*) dictionary; + } + lz4sd->externalDict = NULL; + lz4sd->extDictSize = 0; + return 1; +} + +/*! LZ4_decoderRingBufferSize() : + * when setting a ring buffer for streaming decompression (optional scenario), + * provides the minimum size of this ring buffer + * to be compatible with any source respecting maxBlockSize condition. + * Note : in a ring buffer scenario, + * blocks are presumed decompressed next to each other. + * When not enough space remains for next block (remainingSize < maxBlockSize), + * decoding resumes from beginning of ring buffer. + * @return : minimum ring buffer size, + * or 0 if there is an error (invalid maxBlockSize). + */ +int LZ4_decoderRingBufferSize(int maxBlockSize) +{ + if (maxBlockSize < 0) return 0; + if (maxBlockSize > LZ4_MAX_INPUT_SIZE) return 0; + if (maxBlockSize < 16) maxBlockSize = 16; + return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize); +} + +/* +*_continue() : + These decoding functions allow decompression of multiple blocks in "streaming" mode. + Previously decoded blocks must still be available at the memory position where they were decoded. + If it's not possible, save the relevant part of decoded data into a safe buffer, + and indicate where it stands using LZ4_setStreamDecode() +*/ +LZ4_FORCE_O2 +int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; + int result; + + if (lz4sd->prefixSize == 0) { + /* The first call, no dictionary yet. */ + assert(lz4sd->extDictSize == 0); + result = LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)result; + lz4sd->prefixEnd = (BYTE*)dest + result; + } else if (lz4sd->prefixEnd == (BYTE*)dest) { + /* They're rolling the current segment. */ + if (lz4sd->prefixSize >= 64 KB - 1) + result = LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); + else if (lz4sd->extDictSize == 0) + result = LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, + lz4sd->prefixSize); + else + result = LZ4_decompress_safe_doubleDict(source, dest, compressedSize, maxOutputSize, + lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize += (size_t)result; + lz4sd->prefixEnd += result; + } else { + /* The buffer wraps around, or they're switching to another buffer. */ + lz4sd->extDictSize = lz4sd->prefixSize; + lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; + result = LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, + lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)result; + lz4sd->prefixEnd = (BYTE*)dest + result; + } + + return result; +} + +LZ4_FORCE_O2 int +LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, + const char* source, char* dest, int originalSize) +{ + LZ4_streamDecode_t_internal* const lz4sd = + (assert(LZ4_streamDecode!=NULL), &LZ4_streamDecode->internal_donotuse); + int result; + + DEBUGLOG(5, "LZ4_decompress_fast_continue (toDecodeSize=%i)", originalSize); + assert(originalSize >= 0); + + if (lz4sd->prefixSize == 0) { + DEBUGLOG(5, "first invocation : no prefix nor extDict"); + assert(lz4sd->extDictSize == 0); + result = LZ4_decompress_fast(source, dest, originalSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)originalSize; + lz4sd->prefixEnd = (BYTE*)dest + originalSize; + } else if (lz4sd->prefixEnd == (BYTE*)dest) { + DEBUGLOG(5, "continue using existing prefix"); + result = LZ4_decompress_unsafe_generic( + (const BYTE*)source, (BYTE*)dest, originalSize, + lz4sd->prefixSize, + lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize += (size_t)originalSize; + lz4sd->prefixEnd += originalSize; + } else { + DEBUGLOG(5, "prefix becomes extDict"); + lz4sd->extDictSize = lz4sd->prefixSize; + lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; + result = LZ4_decompress_fast_extDict(source, dest, originalSize, + lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)originalSize; + lz4sd->prefixEnd = (BYTE*)dest + originalSize; + } + + return result; +} + + +/* +Advanced decoding functions : +*_usingDict() : + These decoding functions work the same as "_continue" ones, + the dictionary must be explicitly provided within parameters +*/ + +int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) +{ + if (dictSize==0) + return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); + if (dictStart+dictSize == dest) { + if (dictSize >= 64 KB - 1) { + return LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, (size_t)dictSize); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, (size_t)dictSize); +} + +int LZ4_decompress_safe_partial_usingDict(const char* source, char* dest, int compressedSize, int targetOutputSize, int dstCapacity, const char* dictStart, int dictSize) +{ + if (dictSize==0) + return LZ4_decompress_safe_partial(source, dest, compressedSize, targetOutputSize, dstCapacity); + if (dictStart+dictSize == dest) { + if (dictSize >= 64 KB - 1) { + return LZ4_decompress_safe_partial_withPrefix64k(source, dest, compressedSize, targetOutputSize, dstCapacity); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_partial_withSmallPrefix(source, dest, compressedSize, targetOutputSize, dstCapacity, (size_t)dictSize); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_partial_forceExtDict(source, dest, compressedSize, targetOutputSize, dstCapacity, dictStart, (size_t)dictSize); +} + +int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize) +{ + if (dictSize==0 || dictStart+dictSize == dest) + return LZ4_decompress_unsafe_generic( + (const BYTE*)source, (BYTE*)dest, originalSize, + (size_t)dictSize, NULL, 0); + assert(dictSize >= 0); + return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, (size_t)dictSize); +} + + +/*=************************************************* +* Obsolete Functions +***************************************************/ +/* obsolete compression functions */ +int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) +{ + return LZ4_compress_default(source, dest, inputSize, maxOutputSize); +} +int LZ4_compress(const char* src, char* dest, int srcSize) +{ + return LZ4_compress_default(src, dest, srcSize, LZ4_compressBound(srcSize)); +} +int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize) +{ + return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1); +} +int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize) +{ + return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1); +} +int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int dstCapacity) +{ + return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1); +} +int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize) +{ + return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1); +} + +/* +These decompression functions are deprecated and should no longer be used. +They are only provided here for compatibility with older user programs. +- LZ4_uncompress is totally equivalent to LZ4_decompress_fast +- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe +*/ +int LZ4_uncompress (const char* source, char* dest, int outputSize) +{ + return LZ4_decompress_fast(source, dest, outputSize); +} +int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) +{ + return LZ4_decompress_safe(source, dest, isize, maxOutputSize); +} + +/* Obsolete Streaming functions */ + +int LZ4_sizeofStreamState(void) { return sizeof(LZ4_stream_t); } + +int LZ4_resetStreamState(void* state, char* inputBuffer) +{ + (void)inputBuffer; + LZ4_resetStream((LZ4_stream_t*)state); + return 0; +} + +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) +void* LZ4_create (char* inputBuffer) +{ + (void)inputBuffer; + return LZ4_createStream(); +} +#endif char* LZ4_slideInputBuffer (void* state) { diff --git a/cbits/lz4.h b/cbits/lz4.h --- a/cbits/lz4.h +++ b/cbits/lz4.h @@ -1,7 +1,7 @@ /* * LZ4 - Fast LZ compression algorithm * Header File - * Copyright (C) 2011-present, Yann Collet. + * Copyright (C) 2011-2020, Yann Collet. BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) @@ -97,37 +97,78 @@ # define LZ4LIB_API LZ4LIB_VISIBILITY #endif +/*! LZ4_FREESTANDING : + * When this macro is set to 1, it enables "freestanding mode" that is + * suitable for typical freestanding environment which doesn't support + * standard C library. + * + * - LZ4_FREESTANDING is a compile-time switch. + * - It requires the following macros to be defined: + * LZ4_memcpy, LZ4_memmove, LZ4_memset. + * - It only enables LZ4/HC functions which don't use heap. + * All LZ4F_* functions are not supported. + * - See tests/freestanding.c to check its basic setup. + */ +#if defined(LZ4_FREESTANDING) && (LZ4_FREESTANDING == 1) +# define LZ4_HEAPMODE 0 +# define LZ4HC_HEAPMODE 0 +# define LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION 1 +# if !defined(LZ4_memcpy) +# error "LZ4_FREESTANDING requires macro 'LZ4_memcpy'." +# endif +# if !defined(LZ4_memset) +# error "LZ4_FREESTANDING requires macro 'LZ4_memset'." +# endif +# if !defined(LZ4_memmove) +# error "LZ4_FREESTANDING requires macro 'LZ4_memmove'." +# endif +#elif ! defined(LZ4_FREESTANDING) +# define LZ4_FREESTANDING 0 +#endif + + /*------ Version ------*/ #define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */ #define LZ4_VERSION_MINOR 9 /* for new (non-breaking) interface capabilities */ -#define LZ4_VERSION_RELEASE 2 /* for tweaks, bug-fixes, or development */ +#define LZ4_VERSION_RELEASE 4 /* for tweaks, bug-fixes, or development */ #define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE) #define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE #define LZ4_QUOTE(str) #str #define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str) -#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) +#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) /* requires v1.7.3+ */ -LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version */ -LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version */ +LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version; requires v1.3.0+ */ +LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version; requires v1.7.5+ */ /*-************************************ * Tuning parameter **************************************/ +#define LZ4_MEMORY_USAGE_MIN 10 +#define LZ4_MEMORY_USAGE_DEFAULT 14 +#define LZ4_MEMORY_USAGE_MAX 20 + /*! * LZ4_MEMORY_USAGE : - * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) - * Increasing memory usage improves compression ratio. - * Reduced memory usage may improve speed, thanks to better cache locality. + * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; ) + * Increasing memory usage improves compression ratio, at the cost of speed. + * Reduced memory usage may improve speed at the cost of ratio, thanks to better cache locality. * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ #ifndef LZ4_MEMORY_USAGE -# define LZ4_MEMORY_USAGE 14 +# define LZ4_MEMORY_USAGE LZ4_MEMORY_USAGE_DEFAULT #endif +#if (LZ4_MEMORY_USAGE < LZ4_MEMORY_USAGE_MIN) +# error "LZ4_MEMORY_USAGE is too small !" +#endif +#if (LZ4_MEMORY_USAGE > LZ4_MEMORY_USAGE_MAX) +# error "LZ4_MEMORY_USAGE is too large !" +#endif + /*-************************************ * Simple Functions **************************************/ @@ -186,7 +227,8 @@ The larger the acceleration value, the faster the algorithm, but also the lesser the compression. It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed. An acceleration value of "1" is the same as regular LZ4_compress_default() - Values <= 0 will be replaced by ACCELERATION_DEFAULT (currently == 1, see lz4.c). + Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT (currently == 1, see lz4.c). + Values > LZ4_ACCELERATION_MAX will be replaced by LZ4_ACCELERATION_MAX (currently == 65537, see lz4.c). */ LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); @@ -212,7 +254,18 @@ * New value is necessarily <= input value. * @return : Nb bytes written into 'dst' (necessarily <= targetDestSize) * or 0 if compression fails. -*/ + * + * Note : from v1.8.2 to v1.9.1, this function had a bug (fixed un v1.9.2+): + * the produced compressed content could, in specific circumstances, + * require to be decompressed into a destination buffer larger + * by at least 1 byte than the content to decompress. + * If an application uses `LZ4_compress_destSize()`, + * it's highly recommended to update liblz4 to v1.9.2 or better. + * If this can't be done or ensured, + * the receiving decompression function should provide + * a dstCapacity which is > decompressedSize, by at least 1 byte. + * See https://github.com/lz4/lz4/issues/859 for details + */ LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize); @@ -220,25 +273,35 @@ * Decompress an LZ4 compressed block, of size 'srcSize' at position 'src', * into destination buffer 'dst' of size 'dstCapacity'. * Up to 'targetOutputSize' bytes will be decoded. - * The function stops decoding on reaching this objective, - * which can boost performance when only the beginning of a block is required. + * The function stops decoding on reaching this objective. + * This can be useful to boost performance + * whenever only the beginning of a block is required. * - * @return : the number of bytes decoded in `dst` (necessarily <= dstCapacity) + * @return : the number of bytes decoded in `dst` (necessarily <= targetOutputSize) * If source stream is detected malformed, function returns a negative result. * - * Note : @return can be < targetOutputSize, if compressed block contains less data. + * Note 1 : @return can be < targetOutputSize, if compressed block contains less data. * - * Note 2 : this function features 2 parameters, targetOutputSize and dstCapacity, - * and expects targetOutputSize <= dstCapacity. - * It effectively stops decoding on reaching targetOutputSize, + * Note 2 : targetOutputSize must be <= dstCapacity + * + * Note 3 : this function effectively stops decoding on reaching targetOutputSize, * so dstCapacity is kind of redundant. - * This is because in a previous version of this function, - * decoding operation would not "break" a sequence in the middle. - * As a consequence, there was no guarantee that decoding would stop at exactly targetOutputSize, + * This is because in older versions of this function, + * decoding operation would still write complete sequences. + * Therefore, there was no guarantee that it would stop writing at exactly targetOutputSize, * it could write more bytes, though only up to dstCapacity. * Some "margin" used to be required for this operation to work properly. - * This is no longer necessary. - * The function nonetheless keeps its signature, in an effort to not break API. + * Thankfully, this is no longer necessary. + * The function nonetheless keeps the same signature, in an effort to preserve API compatibility. + * + * Note 4 : If srcSize is the exact size of the block, + * then targetOutputSize can be any value, + * including larger than the block's decompressed size. + * The function will, at most, generate block's decompressed size. + * + * Note 5 : If srcSize is _larger_ than block's compressed size, + * then targetOutputSize **MUST** be <= block's decompressed size. + * Otherwise, *silent corruption will occur*. */ LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity); @@ -248,8 +311,25 @@ ***********************************************/ typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */ +/** + Note about RC_INVOKED + + - RC_INVOKED is predefined symbol of rc.exe (the resource compiler which is part of MSVC/Visual Studio). + https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros + + - Since rc.exe is a legacy compiler, it truncates long symbol (> 30 chars) + and reports warning "RC4011: identifier truncated". + + - To eliminate the warning, we surround long preprocessor symbol with + "#if !defined(RC_INVOKED) ... #endif" block that means + "skip this block when rc.exe is trying to read it". +*/ +#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */ +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) LZ4LIB_API LZ4_stream_t* LZ4_createStream(void); LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr); +#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */ +#endif /*! LZ4_resetStream_fast() : v1.9.0+ * Use this to prepare an LZ4_stream_t for a new chain of dependent blocks @@ -333,8 +413,12 @@ * creation / destruction of streaming decompression tracking context. * A tracking context can be re-used multiple times. */ +#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */ +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void); LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream); +#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */ +#endif /*! LZ4_setStreamDecode() : * An LZ4_streamDecode_t context can be allocated once and re-used multiple times. @@ -384,7 +468,10 @@ * save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression, * then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block. */ -LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity); +LZ4LIB_API int +LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, + const char* src, char* dst, + int srcSize, int dstCapacity); /*! LZ4_decompress_*_usingDict() : @@ -395,8 +482,17 @@ * Performance tip : Decompression speed can be substantially increased * when dst == dictStart + dictSize. */ -LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize); +LZ4LIB_API int +LZ4_decompress_safe_usingDict(const char* src, char* dst, + int srcSize, int dstCapacity, + const char* dictStart, int dictSize); +LZ4LIB_API int +LZ4_decompress_safe_partial_usingDict(const char* src, char* dst, + int compressedSize, + int targetOutputSize, int maxOutputSize, + const char* dictStart, int dictSize); + #endif /* LZ4_H_2983827168210 */ @@ -474,13 +570,15 @@ * stream (and source buffer) must remain in-place / accessible / unchanged * through the completion of the first compression call on the stream. */ -LZ4LIB_STATIC_API void LZ4_attach_dictionary(LZ4_stream_t* workingStream, const LZ4_stream_t* dictionaryStream); +LZ4LIB_STATIC_API void +LZ4_attach_dictionary(LZ4_stream_t* workingStream, + const LZ4_stream_t* dictionaryStream); /*! In-place compression and decompression * * It's possible to have input and output sharing the same buffer, - * for highly contrained memory environments. + * for highly constrained memory environments. * In both cases, it requires input to lay at the end of the buffer, * and decompression to start at beginning of the buffer. * Buffer size must feature some margin, hence be larger than final size. @@ -547,75 +645,53 @@ #define LZ4_H_98237428734687 /*-************************************************************ - * PRIVATE DEFINITIONS + * Private Definitions ************************************************************** * Do not use these definitions directly. * They are only exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`. - * Accessing members will expose code to API and/or ABI break in future versions of the library. + * Accessing members will expose user code to API and/or ABI break in future versions of the library. **************************************************************/ #define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2) #define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE) #define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */ #if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) -#include - -typedef struct LZ4_stream_t_internal LZ4_stream_t_internal; -struct LZ4_stream_t_internal { - uint32_t hashTable[LZ4_HASH_SIZE_U32]; - uint32_t currentOffset; - uint16_t dirty; - uint16_t tableType; - const uint8_t* dictionary; - const LZ4_stream_t_internal* dictCtx; - uint32_t dictSize; -}; - -typedef struct { - const uint8_t* externalDict; - size_t extDictSize; - const uint8_t* prefixEnd; - size_t prefixSize; -} LZ4_streamDecode_t_internal; - +# include + typedef int8_t LZ4_i8; + typedef uint8_t LZ4_byte; + typedef uint16_t LZ4_u16; + typedef uint32_t LZ4_u32; #else + typedef signed char LZ4_i8; + typedef unsigned char LZ4_byte; + typedef unsigned short LZ4_u16; + typedef unsigned int LZ4_u32; +#endif +/*! LZ4_stream_t : + * Never ever use below internal definitions directly ! + * These definitions are not API/ABI safe, and may change in future versions. + * If you need static allocation, declare or allocate an LZ4_stream_t object. +**/ + typedef struct LZ4_stream_t_internal LZ4_stream_t_internal; struct LZ4_stream_t_internal { - unsigned int hashTable[LZ4_HASH_SIZE_U32]; - unsigned int currentOffset; - unsigned short dirty; - unsigned short tableType; - const unsigned char* dictionary; + LZ4_u32 hashTable[LZ4_HASH_SIZE_U32]; + const LZ4_byte* dictionary; const LZ4_stream_t_internal* dictCtx; - unsigned int dictSize; + LZ4_u32 currentOffset; + LZ4_u32 tableType; + LZ4_u32 dictSize; + /* Implicit padding to ensure structure is aligned */ }; -typedef struct { - const unsigned char* externalDict; - const unsigned char* prefixEnd; - size_t extDictSize; - size_t prefixSize; -} LZ4_streamDecode_t_internal; - -#endif - -/*! LZ4_stream_t : - * information structure to track an LZ4 stream. - * LZ4_stream_t can also be created using LZ4_createStream(), which is recommended. - * The structure definition can be convenient for static allocation - * (on stack, or as part of larger structure). - * Init this structure with LZ4_initStream() before first use. - * note : only use this definition in association with static linking ! - * this definition is not API/ABI safe, and may change in a future version. - */ -#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4 + ((sizeof(void*)==16) ? 4 : 0) /*AS-400*/ ) -#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long)) +#define LZ4_STREAM_MINSIZE ((1UL << LZ4_MEMORY_USAGE) + 32) /* static size, for inter-version compatibility */ union LZ4_stream_u { - unsigned long long table[LZ4_STREAMSIZE_U64]; + char minStateSize[LZ4_STREAM_MINSIZE]; LZ4_stream_t_internal internal_donotuse; -} ; /* previously typedef'd to LZ4_stream_t */ +}; /* previously typedef'd to LZ4_stream_t */ + /*! LZ4_initStream() : v1.9.0+ * An LZ4_stream_t structure must be initialized at least once. * This is automatically done when invoking LZ4_createStream(), @@ -629,21 +705,25 @@ * In which case, the function will @return NULL. * Note2: An LZ4_stream_t structure guarantees correct alignment and size. * Note3: Before v1.9.0, use LZ4_resetStream() instead - */ +**/ LZ4LIB_API LZ4_stream_t* LZ4_initStream (void* buffer, size_t size); /*! LZ4_streamDecode_t : - * information structure to track an LZ4 stream during decompression. - * init this structure using LZ4_setStreamDecode() before first use. - * note : only use in association with static linking ! - * this definition is not API/ABI safe, - * and may change in a future version ! - */ -#define LZ4_STREAMDECODESIZE_U64 (4 + ((sizeof(void*)==16) ? 2 : 0) /*AS-400*/ ) -#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long)) + * Never ever use below internal definitions directly ! + * These definitions are not API/ABI safe, and may change in future versions. + * If you need static allocation, declare or allocate an LZ4_streamDecode_t object. +**/ +typedef struct { + const LZ4_byte* externalDict; + const LZ4_byte* prefixEnd; + size_t extDictSize; + size_t prefixSize; +} LZ4_streamDecode_t_internal; + +#define LZ4_STREAMDECODE_MINSIZE 32 union LZ4_streamDecode_u { - unsigned long long table[LZ4_STREAMDECODESIZE_U64]; + char minStateSize[LZ4_STREAMDECODE_MINSIZE]; LZ4_streamDecode_t_internal internal_donotuse; } ; /* previously typedef'd to LZ4_streamDecode_t */ @@ -667,22 +747,21 @@ #ifdef LZ4_DISABLE_DEPRECATE_WARNINGS # define LZ4_DEPRECATED(message) /* disable deprecation warnings */ #else -# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) # if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */ # define LZ4_DEPRECATED(message) [[deprecated(message)]] -# elif (LZ4_GCC_VERSION >= 405) || defined(__clang__) -# define LZ4_DEPRECATED(message) __attribute__((deprecated(message))) -# elif (LZ4_GCC_VERSION >= 301) -# define LZ4_DEPRECATED(message) __attribute__((deprecated)) # elif defined(_MSC_VER) # define LZ4_DEPRECATED(message) __declspec(deprecated(message)) +# elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 45)) +# define LZ4_DEPRECATED(message) __attribute__((deprecated(message))) +# elif defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 31) +# define LZ4_DEPRECATED(message) __attribute__((deprecated)) # else -# pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler") -# define LZ4_DEPRECATED(message) +# pragma message("WARNING: LZ4_DEPRECATED needs custom implementation for this compiler") +# define LZ4_DEPRECATED(message) /* disabled */ # endif #endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */ -/* Obsolete compression functions */ +/*! Obsolete compression functions (since v1.7.3) */ LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* src, char* dest, int srcSize); LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* src, char* dest, int srcSize, int maxOutputSize); LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize); @@ -690,11 +769,12 @@ LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize); LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize); -/* Obsolete decompression functions */ +/*! Obsolete decompression functions (since v1.8.0) */ LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize); LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize); -/* Obsolete streaming functions; degraded functionality; do not use! +/* Obsolete streaming functions (since v1.7.0) + * degraded functionality; do not use! * * In order to perform streaming compression, these functions depended on data * that is no longer tracked in the state. They have been preserved as well as @@ -708,23 +788,22 @@ LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API int LZ4_resetStreamState(void* state, char* inputBuffer); LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API char* LZ4_slideInputBuffer (void* state); -/* Obsolete streaming decoding functions */ +/*! Obsolete streaming decoding functions (since v1.7.0) */ LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize); LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize); -/*! LZ4_decompress_fast() : **unsafe!** +/*! Obsolete LZ4_decompress_fast variants (since v1.9.0) : * These functions used to be faster than LZ4_decompress_safe(), - * but it has changed, and they are now slower than LZ4_decompress_safe(). + * but this is no longer the case. They are now slower. * This is because LZ4_decompress_fast() doesn't know the input size, - * and therefore must progress more cautiously in the input buffer to not read beyond the end of block. + * and therefore must progress more cautiously into the input buffer to not read beyond the end of block. * On top of that `LZ4_decompress_fast()` is not protected vs malformed or malicious inputs, making it a security liability. * As a consequence, LZ4_decompress_fast() is strongly discouraged, and deprecated. * * The last remaining LZ4_decompress_fast() specificity is that * it can decompress a block without knowing its compressed size. - * Such functionality could be achieved in a more secure manner, - * by also providing the maximum size of input buffer, - * but it would require new prototypes, and adaptation of the implementation to this new use case. + * Such functionality can be achieved in a more secure manner + * by employing LZ4_decompress_safe_partial(). * * Parameters: * originalSize : is the uncompressed size to regenerate. @@ -739,7 +818,6 @@ * But they may happen if input data is invalid (error or intentional tampering). * As a consequence, use these functions in trusted environments with trusted data **only**. */ - LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize); LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_continue() instead") diff --git a/cbits/lz4frame.c b/cbits/lz4frame.c new file mode 100644 --- /dev/null +++ b/cbits/lz4frame.c @@ -0,0 +1,2078 @@ +/* + * LZ4 auto-framing library + * Copyright (C) 2011-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You can contact the author at : + * - LZ4 homepage : http://www.lz4.org + * - LZ4 source repository : https://github.com/lz4/lz4 + */ + +/* LZ4F is a stand-alone API to create LZ4-compressed Frames + * in full conformance with specification v1.6.1 . + * This library rely upon memory management capabilities (malloc, free) + * provided either by , + * or redirected towards another library of user's choice + * (see Memory Routines below). + */ + + +/*-************************************ +* Compiler Options +**************************************/ +#ifdef _MSC_VER /* Visual Studio */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +#endif + + +/*-************************************ +* Tuning parameters +**************************************/ +/* + * LZ4F_HEAPMODE : + * Select how default compression functions will allocate memory for their hash table, + * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()). + */ +#ifndef LZ4F_HEAPMODE +# define LZ4F_HEAPMODE 0 +#endif + + +/*-************************************ +* Library declarations +**************************************/ +#define LZ4F_STATIC_LINKING_ONLY +#include "lz4frame.h" +#define LZ4_STATIC_LINKING_ONLY +#include "lz4.h" +#define LZ4_HC_STATIC_LINKING_ONLY +#include "lz4hc.h" +#define XXH_STATIC_LINKING_ONLY +#include "xxhash.h" + + +/*-************************************ +* Memory routines +**************************************/ +/* + * User may redirect invocations of + * malloc(), calloc() and free() + * towards another library or solution of their choice + * by modifying below section. +**/ + +#include /* memset, memcpy, memmove */ +#ifndef LZ4_SRC_INCLUDED /* avoid redefinition when sources are coalesced */ +# define MEM_INIT(p,v,s) memset((p),(v),(s)) +#endif + +#ifndef LZ4_SRC_INCLUDED /* avoid redefinition when sources are coalesced */ +# include /* malloc, calloc, free */ +# define ALLOC(s) malloc(s) +# define ALLOC_AND_ZERO(s) calloc(1,(s)) +# define FREEMEM(p) free(p) +#endif + +static void* LZ4F_calloc(size_t s, LZ4F_CustomMem cmem) +{ + /* custom calloc defined : use it */ + if (cmem.customCalloc != NULL) { + return cmem.customCalloc(cmem.opaqueState, s); + } + /* nothing defined : use default 's calloc() */ + if (cmem.customAlloc == NULL) { + return ALLOC_AND_ZERO(s); + } + /* only custom alloc defined : use it, and combine it with memset() */ + { void* const p = cmem.customAlloc(cmem.opaqueState, s); + if (p != NULL) MEM_INIT(p, 0, s); + return p; +} } + +static void* LZ4F_malloc(size_t s, LZ4F_CustomMem cmem) +{ + /* custom malloc defined : use it */ + if (cmem.customAlloc != NULL) { + return cmem.customAlloc(cmem.opaqueState, s); + } + /* nothing defined : use default 's malloc() */ + return ALLOC(s); +} + +static void LZ4F_free(void* p, LZ4F_CustomMem cmem) +{ + /* custom malloc defined : use it */ + if (cmem.customFree != NULL) { + cmem.customFree(cmem.opaqueState, p); + return; + } + /* nothing defined : use default 's free() */ + FREEMEM(p); +} + + +/*-************************************ +* Debug +**************************************/ +#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=1) +# include +#else +# ifndef assert +# define assert(condition) ((void)0) +# endif +#endif + +#define LZ4F_STATIC_ASSERT(c) { enum { LZ4F_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ + +#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2) && !defined(DEBUGLOG) +# include +static int g_debuglog_enable = 1; +# define DEBUGLOG(l, ...) { \ + if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \ + fprintf(stderr, __FILE__ ": "); \ + fprintf(stderr, __VA_ARGS__); \ + fprintf(stderr, " \n"); \ + } } +#else +# define DEBUGLOG(l, ...) {} /* disabled */ +#endif + + +/*-************************************ +* Basic Types +**************************************/ +#if !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) +# include + typedef uint8_t BYTE; + typedef uint16_t U16; + typedef uint32_t U32; + typedef int32_t S32; + typedef uint64_t U64; +#else + typedef unsigned char BYTE; + typedef unsigned short U16; + typedef unsigned int U32; + typedef signed int S32; + typedef unsigned long long U64; +#endif + + +/* unoptimized version; solves endianness & alignment issues */ +static U32 LZ4F_readLE32 (const void* src) +{ + const BYTE* const srcPtr = (const BYTE*)src; + U32 value32 = srcPtr[0]; + value32 += ((U32)srcPtr[1])<< 8; + value32 += ((U32)srcPtr[2])<<16; + value32 += ((U32)srcPtr[3])<<24; + return value32; +} + +static void LZ4F_writeLE32 (void* dst, U32 value32) +{ + BYTE* const dstPtr = (BYTE*)dst; + dstPtr[0] = (BYTE)value32; + dstPtr[1] = (BYTE)(value32 >> 8); + dstPtr[2] = (BYTE)(value32 >> 16); + dstPtr[3] = (BYTE)(value32 >> 24); +} + +static U64 LZ4F_readLE64 (const void* src) +{ + const BYTE* const srcPtr = (const BYTE*)src; + U64 value64 = srcPtr[0]; + value64 += ((U64)srcPtr[1]<<8); + value64 += ((U64)srcPtr[2]<<16); + value64 += ((U64)srcPtr[3]<<24); + value64 += ((U64)srcPtr[4]<<32); + value64 += ((U64)srcPtr[5]<<40); + value64 += ((U64)srcPtr[6]<<48); + value64 += ((U64)srcPtr[7]<<56); + return value64; +} + +static void LZ4F_writeLE64 (void* dst, U64 value64) +{ + BYTE* const dstPtr = (BYTE*)dst; + dstPtr[0] = (BYTE)value64; + dstPtr[1] = (BYTE)(value64 >> 8); + dstPtr[2] = (BYTE)(value64 >> 16); + dstPtr[3] = (BYTE)(value64 >> 24); + dstPtr[4] = (BYTE)(value64 >> 32); + dstPtr[5] = (BYTE)(value64 >> 40); + dstPtr[6] = (BYTE)(value64 >> 48); + dstPtr[7] = (BYTE)(value64 >> 56); +} + + +/*-************************************ +* Constants +**************************************/ +#ifndef LZ4_SRC_INCLUDED /* avoid double definition */ +# define KB *(1<<10) +# define MB *(1<<20) +# define GB *(1<<30) +#endif + +#define _1BIT 0x01 +#define _2BITS 0x03 +#define _3BITS 0x07 +#define _4BITS 0x0F +#define _8BITS 0xFF + +#define LZ4F_BLOCKUNCOMPRESSED_FLAG 0x80000000U +#define LZ4F_BLOCKSIZEID_DEFAULT LZ4F_max64KB + +static const size_t minFHSize = LZ4F_HEADER_SIZE_MIN; /* 7 */ +static const size_t maxFHSize = LZ4F_HEADER_SIZE_MAX; /* 19 */ +static const size_t BHSize = LZ4F_BLOCK_HEADER_SIZE; /* block header : size, and compress flag */ +static const size_t BFSize = LZ4F_BLOCK_CHECKSUM_SIZE; /* block footer : checksum (optional) */ + + +/*-************************************ +* Structures and local types +**************************************/ + +typedef enum { LZ4B_COMPRESSED, LZ4B_UNCOMPRESSED} LZ4F_blockCompression_t; + +typedef struct LZ4F_cctx_s +{ + LZ4F_CustomMem cmem; + LZ4F_preferences_t prefs; + U32 version; + U32 cStage; + const LZ4F_CDict* cdict; + size_t maxBlockSize; + size_t maxBufferSize; + BYTE* tmpBuff; /* internal buffer, for streaming */ + BYTE* tmpIn; /* starting position of data compress within internal buffer (>= tmpBuff) */ + size_t tmpInSize; /* amount of data to compress after tmpIn */ + U64 totalInSize; + XXH32_state_t xxh; + void* lz4CtxPtr; + U16 lz4CtxAlloc; /* sized for: 0 = none, 1 = lz4 ctx, 2 = lz4hc ctx */ + U16 lz4CtxState; /* in use as: 0 = none, 1 = lz4 ctx, 2 = lz4hc ctx */ + LZ4F_blockCompression_t blockCompression; +} LZ4F_cctx_t; + + +/*-************************************ +* Error management +**************************************/ +#define LZ4F_GENERATE_STRING(STRING) #STRING, +static const char* LZ4F_errorStrings[] = { LZ4F_LIST_ERRORS(LZ4F_GENERATE_STRING) }; + + +unsigned LZ4F_isError(LZ4F_errorCode_t code) +{ + return (code > (LZ4F_errorCode_t)(-LZ4F_ERROR_maxCode)); +} + +const char* LZ4F_getErrorName(LZ4F_errorCode_t code) +{ + static const char* codeError = "Unspecified error code"; + if (LZ4F_isError(code)) return LZ4F_errorStrings[-(int)(code)]; + return codeError; +} + +LZ4F_errorCodes LZ4F_getErrorCode(size_t functionResult) +{ + if (!LZ4F_isError(functionResult)) return LZ4F_OK_NoError; + return (LZ4F_errorCodes)(-(ptrdiff_t)functionResult); +} + +static LZ4F_errorCode_t LZ4F_returnErrorCode(LZ4F_errorCodes code) +{ + /* A compilation error here means sizeof(ptrdiff_t) is not large enough */ + LZ4F_STATIC_ASSERT(sizeof(ptrdiff_t) >= sizeof(size_t)); + return (LZ4F_errorCode_t)-(ptrdiff_t)code; +} + +#define RETURN_ERROR(e) return LZ4F_returnErrorCode(LZ4F_ERROR_ ## e) + +#define RETURN_ERROR_IF(c,e) if (c) RETURN_ERROR(e) + +#define FORWARD_IF_ERROR(r) if (LZ4F_isError(r)) return (r) + +unsigned LZ4F_getVersion(void) { return LZ4F_VERSION; } + +int LZ4F_compressionLevel_max(void) { return LZ4HC_CLEVEL_MAX; } + +size_t LZ4F_getBlockSize(LZ4F_blockSizeID_t blockSizeID) +{ + static const size_t blockSizes[4] = { 64 KB, 256 KB, 1 MB, 4 MB }; + + if (blockSizeID == 0) blockSizeID = LZ4F_BLOCKSIZEID_DEFAULT; + if (blockSizeID < LZ4F_max64KB || blockSizeID > LZ4F_max4MB) + RETURN_ERROR(maxBlockSize_invalid); + { int const blockSizeIdx = (int)blockSizeID - (int)LZ4F_max64KB; + return blockSizes[blockSizeIdx]; +} } + +/*-************************************ +* Private functions +**************************************/ +#define MIN(a,b) ( (a) < (b) ? (a) : (b) ) + +static BYTE LZ4F_headerChecksum (const void* header, size_t length) +{ + U32 const xxh = XXH32(header, length, 0); + return (BYTE)(xxh >> 8); +} + + +/*-************************************ +* Simple-pass compression functions +**************************************/ +static LZ4F_blockSizeID_t LZ4F_optimalBSID(const LZ4F_blockSizeID_t requestedBSID, + const size_t srcSize) +{ + LZ4F_blockSizeID_t proposedBSID = LZ4F_max64KB; + size_t maxBlockSize = 64 KB; + while (requestedBSID > proposedBSID) { + if (srcSize <= maxBlockSize) + return proposedBSID; + proposedBSID = (LZ4F_blockSizeID_t)((int)proposedBSID + 1); + maxBlockSize <<= 2; + } + return requestedBSID; +} + +/*! LZ4F_compressBound_internal() : + * Provides dstCapacity given a srcSize to guarantee operation success in worst case situations. + * prefsPtr is optional : if NULL is provided, preferences will be set to cover worst case scenario. + * @return is always the same for a srcSize and prefsPtr, so it can be relied upon to size reusable buffers. + * When srcSize==0, LZ4F_compressBound() provides an upper bound for LZ4F_flush() and LZ4F_compressEnd() operations. + */ +static size_t LZ4F_compressBound_internal(size_t srcSize, + const LZ4F_preferences_t* preferencesPtr, + size_t alreadyBuffered) +{ + LZ4F_preferences_t prefsNull = LZ4F_INIT_PREFERENCES; + prefsNull.frameInfo.contentChecksumFlag = LZ4F_contentChecksumEnabled; /* worst case */ + prefsNull.frameInfo.blockChecksumFlag = LZ4F_blockChecksumEnabled; /* worst case */ + { const LZ4F_preferences_t* const prefsPtr = (preferencesPtr==NULL) ? &prefsNull : preferencesPtr; + U32 const flush = prefsPtr->autoFlush | (srcSize==0); + LZ4F_blockSizeID_t const blockID = prefsPtr->frameInfo.blockSizeID; + size_t const blockSize = LZ4F_getBlockSize(blockID); + size_t const maxBuffered = blockSize - 1; + size_t const bufferedSize = MIN(alreadyBuffered, maxBuffered); + size_t const maxSrcSize = srcSize + bufferedSize; + unsigned const nbFullBlocks = (unsigned)(maxSrcSize / blockSize); + size_t const partialBlockSize = maxSrcSize & (blockSize-1); + size_t const lastBlockSize = flush ? partialBlockSize : 0; + unsigned const nbBlocks = nbFullBlocks + (lastBlockSize>0); + + size_t const blockCRCSize = BFSize * prefsPtr->frameInfo.blockChecksumFlag; + size_t const frameEnd = BHSize + (prefsPtr->frameInfo.contentChecksumFlag*BFSize); + + return ((BHSize + blockCRCSize) * nbBlocks) + + (blockSize * nbFullBlocks) + lastBlockSize + frameEnd; + } +} + +size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr) +{ + LZ4F_preferences_t prefs; + size_t const headerSize = maxFHSize; /* max header size, including optional fields */ + + if (preferencesPtr!=NULL) prefs = *preferencesPtr; + else MEM_INIT(&prefs, 0, sizeof(prefs)); + prefs.autoFlush = 1; + + return headerSize + LZ4F_compressBound_internal(srcSize, &prefs, 0);; +} + + +/*! LZ4F_compressFrame_usingCDict() : + * Compress srcBuffer using a dictionary, in a single step. + * cdict can be NULL, in which case, no dictionary is used. + * dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr). + * The LZ4F_preferences_t structure is optional : you may provide NULL as argument, + * however, it's the only way to provide a dictID, so it's not recommended. + * @return : number of bytes written into dstBuffer, + * or an error code if it fails (can be tested using LZ4F_isError()) + */ +size_t LZ4F_compressFrame_usingCDict(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_CDict* cdict, + const LZ4F_preferences_t* preferencesPtr) +{ + LZ4F_preferences_t prefs; + LZ4F_compressOptions_t options; + BYTE* const dstStart = (BYTE*) dstBuffer; + BYTE* dstPtr = dstStart; + BYTE* const dstEnd = dstStart + dstCapacity; + + if (preferencesPtr!=NULL) + prefs = *preferencesPtr; + else + MEM_INIT(&prefs, 0, sizeof(prefs)); + if (prefs.frameInfo.contentSize != 0) + prefs.frameInfo.contentSize = (U64)srcSize; /* auto-correct content size if selected (!=0) */ + + prefs.frameInfo.blockSizeID = LZ4F_optimalBSID(prefs.frameInfo.blockSizeID, srcSize); + prefs.autoFlush = 1; + if (srcSize <= LZ4F_getBlockSize(prefs.frameInfo.blockSizeID)) + prefs.frameInfo.blockMode = LZ4F_blockIndependent; /* only one block => no need for inter-block link */ + + MEM_INIT(&options, 0, sizeof(options)); + options.stableSrc = 1; + + RETURN_ERROR_IF(dstCapacity < LZ4F_compressFrameBound(srcSize, &prefs), dstMaxSize_tooSmall); + + { size_t const headerSize = LZ4F_compressBegin_usingCDict(cctx, dstBuffer, dstCapacity, cdict, &prefs); /* write header */ + FORWARD_IF_ERROR(headerSize); + dstPtr += headerSize; /* header size */ } + + assert(dstEnd >= dstPtr); + { size_t const cSize = LZ4F_compressUpdate(cctx, dstPtr, (size_t)(dstEnd-dstPtr), srcBuffer, srcSize, &options); + FORWARD_IF_ERROR(cSize); + dstPtr += cSize; } + + assert(dstEnd >= dstPtr); + { size_t const tailSize = LZ4F_compressEnd(cctx, dstPtr, (size_t)(dstEnd-dstPtr), &options); /* flush last block, and generate suffix */ + FORWARD_IF_ERROR(tailSize); + dstPtr += tailSize; } + + assert(dstEnd >= dstStart); + return (size_t)(dstPtr - dstStart); +} + + +/*! LZ4F_compressFrame() : + * Compress an entire srcBuffer into a valid LZ4 frame, in a single step. + * dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr). + * The LZ4F_preferences_t structure is optional : you can provide NULL as argument. All preferences will be set to default. + * @return : number of bytes written into dstBuffer. + * or an error code if it fails (can be tested using LZ4F_isError()) + */ +size_t LZ4F_compressFrame(void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_preferences_t* preferencesPtr) +{ + size_t result; +#if (LZ4F_HEAPMODE) + LZ4F_cctx_t* cctxPtr; + result = LZ4F_createCompressionContext(&cctxPtr, LZ4F_VERSION); + FORWARD_IF_ERROR(result); +#else + LZ4F_cctx_t cctx; + LZ4_stream_t lz4ctx; + LZ4F_cctx_t* const cctxPtr = &cctx; + + MEM_INIT(&cctx, 0, sizeof(cctx)); + cctx.version = LZ4F_VERSION; + cctx.maxBufferSize = 5 MB; /* mess with real buffer size to prevent dynamic allocation; works only because autoflush==1 & stableSrc==1 */ + if ( preferencesPtr == NULL + || preferencesPtr->compressionLevel < LZ4HC_CLEVEL_MIN ) { + LZ4_initStream(&lz4ctx, sizeof(lz4ctx)); + cctxPtr->lz4CtxPtr = &lz4ctx; + cctxPtr->lz4CtxAlloc = 1; + cctxPtr->lz4CtxState = 1; + } +#endif + DEBUGLOG(4, "LZ4F_compressFrame"); + + result = LZ4F_compressFrame_usingCDict(cctxPtr, dstBuffer, dstCapacity, + srcBuffer, srcSize, + NULL, preferencesPtr); + +#if (LZ4F_HEAPMODE) + LZ4F_freeCompressionContext(cctxPtr); +#else + if ( preferencesPtr != NULL + && preferencesPtr->compressionLevel >= LZ4HC_CLEVEL_MIN ) { + LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem); + } +#endif + return result; +} + + +/*-*************************************************** +* Dictionary compression +*****************************************************/ + +struct LZ4F_CDict_s { + LZ4F_CustomMem cmem; + void* dictContent; + LZ4_stream_t* fastCtx; + LZ4_streamHC_t* HCCtx; +}; /* typedef'd to LZ4F_CDict within lz4frame_static.h */ + +LZ4F_CDict* +LZ4F_createCDict_advanced(LZ4F_CustomMem cmem, const void* dictBuffer, size_t dictSize) +{ + const char* dictStart = (const char*)dictBuffer; + LZ4F_CDict* const cdict = (LZ4F_CDict*)LZ4F_malloc(sizeof(*cdict), cmem); + DEBUGLOG(4, "LZ4F_createCDict_advanced"); + if (!cdict) return NULL; + cdict->cmem = cmem; + if (dictSize > 64 KB) { + dictStart += dictSize - 64 KB; + dictSize = 64 KB; + } + cdict->dictContent = LZ4F_malloc(dictSize, cmem); + cdict->fastCtx = (LZ4_stream_t*)LZ4F_malloc(sizeof(LZ4_stream_t), cmem); + if (cdict->fastCtx) + LZ4_initStream(cdict->fastCtx, sizeof(LZ4_stream_t)); + cdict->HCCtx = (LZ4_streamHC_t*)LZ4F_malloc(sizeof(LZ4_streamHC_t), cmem); + if (cdict->HCCtx) + LZ4_initStream(cdict->HCCtx, sizeof(LZ4_streamHC_t)); + if (!cdict->dictContent || !cdict->fastCtx || !cdict->HCCtx) { + LZ4F_freeCDict(cdict); + return NULL; + } + memcpy(cdict->dictContent, dictStart, dictSize); + LZ4_loadDict (cdict->fastCtx, (const char*)cdict->dictContent, (int)dictSize); + LZ4_setCompressionLevel(cdict->HCCtx, LZ4HC_CLEVEL_DEFAULT); + LZ4_loadDictHC(cdict->HCCtx, (const char*)cdict->dictContent, (int)dictSize); + return cdict; +} + +/*! LZ4F_createCDict() : + * When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once. + * LZ4F_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay. + * LZ4F_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only. + * @dictBuffer can be released after LZ4F_CDict creation, since its content is copied within CDict + * @return : digested dictionary for compression, or NULL if failed */ +LZ4F_CDict* LZ4F_createCDict(const void* dictBuffer, size_t dictSize) +{ + DEBUGLOG(4, "LZ4F_createCDict"); + return LZ4F_createCDict_advanced(LZ4F_defaultCMem, dictBuffer, dictSize); +} + +void LZ4F_freeCDict(LZ4F_CDict* cdict) +{ + if (cdict==NULL) return; /* support free on NULL */ + LZ4F_free(cdict->dictContent, cdict->cmem); + LZ4F_free(cdict->fastCtx, cdict->cmem); + LZ4F_free(cdict->HCCtx, cdict->cmem); + LZ4F_free(cdict, cdict->cmem); +} + + +/*-********************************* +* Advanced compression functions +***********************************/ + +LZ4F_cctx* +LZ4F_createCompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version) +{ + LZ4F_cctx* const cctxPtr = + (LZ4F_cctx*)LZ4F_calloc(sizeof(LZ4F_cctx), customMem); + if (cctxPtr==NULL) return NULL; + + cctxPtr->cmem = customMem; + cctxPtr->version = version; + cctxPtr->cStage = 0; /* Uninitialized. Next stage : init cctx */ + + return cctxPtr; +} + +/*! LZ4F_createCompressionContext() : + * The first thing to do is to create a compressionContext object, which will be used in all compression operations. + * This is achieved using LZ4F_createCompressionContext(), which takes as argument a version and an LZ4F_preferences_t structure. + * The version provided MUST be LZ4F_VERSION. It is intended to track potential incompatible differences between different binaries. + * The function will provide a pointer to an allocated LZ4F_compressionContext_t object. + * If the result LZ4F_errorCode_t is not OK_NoError, there was an error during context creation. + * Object can release its memory using LZ4F_freeCompressionContext(); +**/ +LZ4F_errorCode_t +LZ4F_createCompressionContext(LZ4F_cctx** LZ4F_compressionContextPtr, unsigned version) +{ + assert(LZ4F_compressionContextPtr != NULL); /* considered a violation of narrow contract */ + /* in case it nonetheless happen in production */ + RETURN_ERROR_IF(LZ4F_compressionContextPtr == NULL, parameter_null); + + *LZ4F_compressionContextPtr = LZ4F_createCompressionContext_advanced(LZ4F_defaultCMem, version); + RETURN_ERROR_IF(*LZ4F_compressionContextPtr==NULL, allocation_failed); + return LZ4F_OK_NoError; +} + + +LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_cctx* cctxPtr) +{ + if (cctxPtr != NULL) { /* support free on NULL */ + LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem); /* note: LZ4_streamHC_t and LZ4_stream_t are simple POD types */ + LZ4F_free(cctxPtr->tmpBuff, cctxPtr->cmem); + LZ4F_free(cctxPtr, cctxPtr->cmem); + } + return LZ4F_OK_NoError; +} + + +/** + * This function prepares the internal LZ4(HC) stream for a new compression, + * resetting the context and attaching the dictionary, if there is one. + * + * It needs to be called at the beginning of each independent compression + * stream (i.e., at the beginning of a frame in blockLinked mode, or at the + * beginning of each block in blockIndependent mode). + */ +static void LZ4F_initStream(void* ctx, + const LZ4F_CDict* cdict, + int level, + LZ4F_blockMode_t blockMode) { + if (level < LZ4HC_CLEVEL_MIN) { + if (cdict != NULL || blockMode == LZ4F_blockLinked) { + /* In these cases, we will call LZ4_compress_fast_continue(), + * which needs an already reset context. Otherwise, we'll call a + * one-shot API. The non-continued APIs internally perform their own + * resets at the beginning of their calls, where they know what + * tableType they need the context to be in. So in that case this + * would be misguided / wasted work. */ + LZ4_resetStream_fast((LZ4_stream_t*)ctx); + } + LZ4_attach_dictionary((LZ4_stream_t *)ctx, cdict ? cdict->fastCtx : NULL); + } else { + LZ4_resetStreamHC_fast((LZ4_streamHC_t*)ctx, level); + LZ4_attach_HC_dictionary((LZ4_streamHC_t *)ctx, cdict ? cdict->HCCtx : NULL); + } +} + +static int ctxTypeID_to_size(int ctxTypeID) { + switch(ctxTypeID) { + case 1: + return LZ4_sizeofState(); + case 2: + return LZ4_sizeofStateHC(); + default: + return 0; + } +} + +/*! LZ4F_compressBegin_usingCDict() : + * init streaming compression AND writes frame header into @dstBuffer. + * @dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes. + * @return : number of bytes written into @dstBuffer for the header + * or an error code (can be tested using LZ4F_isError()) + */ +size_t LZ4F_compressBegin_usingCDict(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const LZ4F_CDict* cdict, + const LZ4F_preferences_t* preferencesPtr) +{ + LZ4F_preferences_t const prefNull = LZ4F_INIT_PREFERENCES; + BYTE* const dstStart = (BYTE*)dstBuffer; + BYTE* dstPtr = dstStart; + + RETURN_ERROR_IF(dstCapacity < maxFHSize, dstMaxSize_tooSmall); + if (preferencesPtr == NULL) preferencesPtr = &prefNull; + cctxPtr->prefs = *preferencesPtr; + + /* cctx Management */ + { U16 const ctxTypeID = (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) ? 1 : 2; + int requiredSize = ctxTypeID_to_size(ctxTypeID); + int allocatedSize = ctxTypeID_to_size(cctxPtr->lz4CtxAlloc); + if (allocatedSize < requiredSize) { + /* not enough space allocated */ + LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem); + if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) { + /* must take ownership of memory allocation, + * in order to respect custom allocator contract */ + cctxPtr->lz4CtxPtr = LZ4F_malloc(sizeof(LZ4_stream_t), cctxPtr->cmem); + if (cctxPtr->lz4CtxPtr) + LZ4_initStream(cctxPtr->lz4CtxPtr, sizeof(LZ4_stream_t)); + } else { + cctxPtr->lz4CtxPtr = LZ4F_malloc(sizeof(LZ4_streamHC_t), cctxPtr->cmem); + if (cctxPtr->lz4CtxPtr) + LZ4_initStreamHC(cctxPtr->lz4CtxPtr, sizeof(LZ4_streamHC_t)); + } + RETURN_ERROR_IF(cctxPtr->lz4CtxPtr == NULL, allocation_failed); + cctxPtr->lz4CtxAlloc = ctxTypeID; + cctxPtr->lz4CtxState = ctxTypeID; + } else if (cctxPtr->lz4CtxState != ctxTypeID) { + /* otherwise, a sufficient buffer is already allocated, + * but we need to reset it to the correct context type */ + if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) { + LZ4_initStream((LZ4_stream_t*)cctxPtr->lz4CtxPtr, sizeof(LZ4_stream_t)); + } else { + LZ4_initStreamHC((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, sizeof(LZ4_streamHC_t)); + LZ4_setCompressionLevel((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel); + } + cctxPtr->lz4CtxState = ctxTypeID; + } } + + /* Buffer Management */ + if (cctxPtr->prefs.frameInfo.blockSizeID == 0) + cctxPtr->prefs.frameInfo.blockSizeID = LZ4F_BLOCKSIZEID_DEFAULT; + cctxPtr->maxBlockSize = LZ4F_getBlockSize(cctxPtr->prefs.frameInfo.blockSizeID); + + { size_t const requiredBuffSize = preferencesPtr->autoFlush ? + ((cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) ? 64 KB : 0) : /* only needs past data up to window size */ + cctxPtr->maxBlockSize + ((cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) ? 128 KB : 0); + + if (cctxPtr->maxBufferSize < requiredBuffSize) { + cctxPtr->maxBufferSize = 0; + LZ4F_free(cctxPtr->tmpBuff, cctxPtr->cmem); + cctxPtr->tmpBuff = (BYTE*)LZ4F_calloc(requiredBuffSize, cctxPtr->cmem); + RETURN_ERROR_IF(cctxPtr->tmpBuff == NULL, allocation_failed); + cctxPtr->maxBufferSize = requiredBuffSize; + } } + cctxPtr->tmpIn = cctxPtr->tmpBuff; + cctxPtr->tmpInSize = 0; + (void)XXH32_reset(&(cctxPtr->xxh), 0); + + /* context init */ + cctxPtr->cdict = cdict; + if (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) { + /* frame init only for blockLinked : blockIndependent will be init at each block */ + LZ4F_initStream(cctxPtr->lz4CtxPtr, cdict, cctxPtr->prefs.compressionLevel, LZ4F_blockLinked); + } + if (preferencesPtr->compressionLevel >= LZ4HC_CLEVEL_MIN) { + LZ4_favorDecompressionSpeed((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, (int)preferencesPtr->favorDecSpeed); + } + + /* Magic Number */ + LZ4F_writeLE32(dstPtr, LZ4F_MAGICNUMBER); + dstPtr += 4; + { BYTE* const headerStart = dstPtr; + + /* FLG Byte */ + *dstPtr++ = (BYTE)(((1 & _2BITS) << 6) /* Version('01') */ + + ((cctxPtr->prefs.frameInfo.blockMode & _1BIT ) << 5) + + ((cctxPtr->prefs.frameInfo.blockChecksumFlag & _1BIT ) << 4) + + ((unsigned)(cctxPtr->prefs.frameInfo.contentSize > 0) << 3) + + ((cctxPtr->prefs.frameInfo.contentChecksumFlag & _1BIT ) << 2) + + (cctxPtr->prefs.frameInfo.dictID > 0) ); + /* BD Byte */ + *dstPtr++ = (BYTE)((cctxPtr->prefs.frameInfo.blockSizeID & _3BITS) << 4); + /* Optional Frame content size field */ + if (cctxPtr->prefs.frameInfo.contentSize) { + LZ4F_writeLE64(dstPtr, cctxPtr->prefs.frameInfo.contentSize); + dstPtr += 8; + cctxPtr->totalInSize = 0; + } + /* Optional dictionary ID field */ + if (cctxPtr->prefs.frameInfo.dictID) { + LZ4F_writeLE32(dstPtr, cctxPtr->prefs.frameInfo.dictID); + dstPtr += 4; + } + /* Header CRC Byte */ + *dstPtr = LZ4F_headerChecksum(headerStart, (size_t)(dstPtr - headerStart)); + dstPtr++; + } + + cctxPtr->cStage = 1; /* header written, now request input data block */ + return (size_t)(dstPtr - dstStart); +} + + +/*! LZ4F_compressBegin() : + * init streaming compression AND writes frame header into @dstBuffer. + * @dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes. + * @preferencesPtr can be NULL, in which case default parameters are selected. + * @return : number of bytes written into dstBuffer for the header + * or an error code (can be tested using LZ4F_isError()) + */ +size_t LZ4F_compressBegin(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const LZ4F_preferences_t* preferencesPtr) +{ + return LZ4F_compressBegin_usingCDict(cctxPtr, dstBuffer, dstCapacity, + NULL, preferencesPtr); +} + + +/* LZ4F_compressBound() : + * @return minimum capacity of dstBuffer for a given srcSize to handle worst case scenario. + * LZ4F_preferences_t structure is optional : if NULL, preferences will be set to cover worst case scenario. + * This function cannot fail. + */ +size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr) +{ + if (preferencesPtr && preferencesPtr->autoFlush) { + return LZ4F_compressBound_internal(srcSize, preferencesPtr, 0); + } + return LZ4F_compressBound_internal(srcSize, preferencesPtr, (size_t)-1); +} + + +typedef int (*compressFunc_t)(void* ctx, const char* src, char* dst, int srcSize, int dstSize, int level, const LZ4F_CDict* cdict); + + +/*! LZ4F_makeBlock(): + * compress a single block, add header and optional checksum. + * assumption : dst buffer capacity is >= BHSize + srcSize + crcSize + */ +static size_t LZ4F_makeBlock(void* dst, + const void* src, size_t srcSize, + compressFunc_t compress, void* lz4ctx, int level, + const LZ4F_CDict* cdict, + LZ4F_blockChecksum_t crcFlag) +{ + BYTE* const cSizePtr = (BYTE*)dst; + U32 cSize; + assert(compress != NULL); + cSize = (U32)compress(lz4ctx, (const char*)src, (char*)(cSizePtr+BHSize), + (int)(srcSize), (int)(srcSize-1), + level, cdict); + + if (cSize == 0 || cSize >= srcSize) { + cSize = (U32)srcSize; + LZ4F_writeLE32(cSizePtr, cSize | LZ4F_BLOCKUNCOMPRESSED_FLAG); + memcpy(cSizePtr+BHSize, src, srcSize); + } else { + LZ4F_writeLE32(cSizePtr, cSize); + } + if (crcFlag) { + U32 const crc32 = XXH32(cSizePtr+BHSize, cSize, 0); /* checksum of compressed data */ + LZ4F_writeLE32(cSizePtr+BHSize+cSize, crc32); + } + return BHSize + cSize + ((U32)crcFlag)*BFSize; +} + + +static int LZ4F_compressBlock(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict) +{ + int const acceleration = (level < 0) ? -level + 1 : 1; + DEBUGLOG(5, "LZ4F_compressBlock (srcSize=%i)", srcSize); + LZ4F_initStream(ctx, cdict, level, LZ4F_blockIndependent); + if (cdict) { + return LZ4_compress_fast_continue((LZ4_stream_t*)ctx, src, dst, srcSize, dstCapacity, acceleration); + } else { + return LZ4_compress_fast_extState_fastReset(ctx, src, dst, srcSize, dstCapacity, acceleration); + } +} + +static int LZ4F_compressBlock_continue(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict) +{ + int const acceleration = (level < 0) ? -level + 1 : 1; + (void)cdict; /* init once at beginning of frame */ + DEBUGLOG(5, "LZ4F_compressBlock_continue (srcSize=%i)", srcSize); + return LZ4_compress_fast_continue((LZ4_stream_t*)ctx, src, dst, srcSize, dstCapacity, acceleration); +} + +static int LZ4F_compressBlockHC(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict) +{ + LZ4F_initStream(ctx, cdict, level, LZ4F_blockIndependent); + if (cdict) { + return LZ4_compress_HC_continue((LZ4_streamHC_t*)ctx, src, dst, srcSize, dstCapacity); + } + return LZ4_compress_HC_extStateHC_fastReset(ctx, src, dst, srcSize, dstCapacity, level); +} + +static int LZ4F_compressBlockHC_continue(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict) +{ + (void)level; (void)cdict; /* init once at beginning of frame */ + return LZ4_compress_HC_continue((LZ4_streamHC_t*)ctx, src, dst, srcSize, dstCapacity); +} + +static int LZ4F_doNotCompressBlock(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict) +{ + (void)ctx; (void)src; (void)dst; (void)srcSize; (void)dstCapacity; (void)level; (void)cdict; + return 0; +} + +static compressFunc_t LZ4F_selectCompression(LZ4F_blockMode_t blockMode, int level, LZ4F_blockCompression_t compressMode) +{ + if (compressMode == LZ4B_UNCOMPRESSED) return LZ4F_doNotCompressBlock; + if (level < LZ4HC_CLEVEL_MIN) { + if (blockMode == LZ4F_blockIndependent) return LZ4F_compressBlock; + return LZ4F_compressBlock_continue; + } + if (blockMode == LZ4F_blockIndependent) return LZ4F_compressBlockHC; + return LZ4F_compressBlockHC_continue; +} + +/* Save history (up to 64KB) into @tmpBuff */ +static int LZ4F_localSaveDict(LZ4F_cctx_t* cctxPtr) +{ + if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) + return LZ4_saveDict ((LZ4_stream_t*)(cctxPtr->lz4CtxPtr), (char*)(cctxPtr->tmpBuff), 64 KB); + return LZ4_saveDictHC ((LZ4_streamHC_t*)(cctxPtr->lz4CtxPtr), (char*)(cctxPtr->tmpBuff), 64 KB); +} + +typedef enum { notDone, fromTmpBuffer, fromSrcBuffer } LZ4F_lastBlockStatus; + +static const LZ4F_compressOptions_t k_cOptionsNull = { 0, { 0, 0, 0 } }; + + + /*! LZ4F_compressUpdateImpl() : + * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary. + * When successful, the function always entirely consumes @srcBuffer. + * src data is either buffered or compressed into @dstBuffer. + * If the block compression does not match the compression of the previous block, the old data is flushed + * and operations continue with the new compression mode. + * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr) when block compression is turned on. + * @compressOptionsPtr is optional : provide NULL to mean "default". + * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered. + * or an error code if it fails (which can be tested using LZ4F_isError()) + * After an error, the state is left in a UB state, and must be re-initialized. + */ +static size_t LZ4F_compressUpdateImpl(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_compressOptions_t* compressOptionsPtr, + LZ4F_blockCompression_t blockCompression) + { + size_t const blockSize = cctxPtr->maxBlockSize; + const BYTE* srcPtr = (const BYTE*)srcBuffer; + const BYTE* const srcEnd = srcPtr + srcSize; + BYTE* const dstStart = (BYTE*)dstBuffer; + BYTE* dstPtr = dstStart; + LZ4F_lastBlockStatus lastBlockCompressed = notDone; + compressFunc_t const compress = LZ4F_selectCompression(cctxPtr->prefs.frameInfo.blockMode, cctxPtr->prefs.compressionLevel, blockCompression); + size_t bytesWritten; + DEBUGLOG(4, "LZ4F_compressUpdate (srcSize=%zu)", srcSize); + + RETURN_ERROR_IF(cctxPtr->cStage != 1, compressionState_uninitialized); /* state must be initialized and waiting for next block */ + if (dstCapacity < LZ4F_compressBound_internal(srcSize, &(cctxPtr->prefs), cctxPtr->tmpInSize)) + RETURN_ERROR(dstMaxSize_tooSmall); + + if (blockCompression == LZ4B_UNCOMPRESSED && dstCapacity < srcSize) + RETURN_ERROR(dstMaxSize_tooSmall); + + /* flush currently written block, to continue with new block compression */ + if (cctxPtr->blockCompression != blockCompression) { + bytesWritten = LZ4F_flush(cctxPtr, dstBuffer, dstCapacity, compressOptionsPtr); + dstPtr += bytesWritten; + cctxPtr->blockCompression = blockCompression; + } + + if (compressOptionsPtr == NULL) compressOptionsPtr = &k_cOptionsNull; + + /* complete tmp buffer */ + if (cctxPtr->tmpInSize > 0) { /* some data already within tmp buffer */ + size_t const sizeToCopy = blockSize - cctxPtr->tmpInSize; + assert(blockSize > cctxPtr->tmpInSize); + if (sizeToCopy > srcSize) { + /* add src to tmpIn buffer */ + memcpy(cctxPtr->tmpIn + cctxPtr->tmpInSize, srcBuffer, srcSize); + srcPtr = srcEnd; + cctxPtr->tmpInSize += srcSize; + /* still needs some CRC */ + } else { + /* complete tmpIn block and then compress it */ + lastBlockCompressed = fromTmpBuffer; + memcpy(cctxPtr->tmpIn + cctxPtr->tmpInSize, srcBuffer, sizeToCopy); + srcPtr += sizeToCopy; + + dstPtr += LZ4F_makeBlock(dstPtr, + cctxPtr->tmpIn, blockSize, + compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel, + cctxPtr->cdict, + cctxPtr->prefs.frameInfo.blockChecksumFlag); + if (cctxPtr->prefs.frameInfo.blockMode==LZ4F_blockLinked) cctxPtr->tmpIn += blockSize; + cctxPtr->tmpInSize = 0; + } } + + while ((size_t)(srcEnd - srcPtr) >= blockSize) { + /* compress full blocks */ + lastBlockCompressed = fromSrcBuffer; + dstPtr += LZ4F_makeBlock(dstPtr, + srcPtr, blockSize, + compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel, + cctxPtr->cdict, + cctxPtr->prefs.frameInfo.blockChecksumFlag); + srcPtr += blockSize; + } + + if ((cctxPtr->prefs.autoFlush) && (srcPtr < srcEnd)) { + /* autoFlush : remaining input (< blockSize) is compressed */ + lastBlockCompressed = fromSrcBuffer; + dstPtr += LZ4F_makeBlock(dstPtr, + srcPtr, (size_t)(srcEnd - srcPtr), + compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel, + cctxPtr->cdict, + cctxPtr->prefs.frameInfo.blockChecksumFlag); + srcPtr = srcEnd; + } + + /* preserve dictionary within @tmpBuff whenever necessary */ + if ((cctxPtr->prefs.frameInfo.blockMode==LZ4F_blockLinked) && (lastBlockCompressed==fromSrcBuffer)) { + /* linked blocks are only supported in compressed mode, see LZ4F_uncompressedUpdate */ + assert(blockCompression == LZ4B_COMPRESSED); + if (compressOptionsPtr->stableSrc) { + cctxPtr->tmpIn = cctxPtr->tmpBuff; /* src is stable : dictionary remains in src across invocations */ + } else { + int const realDictSize = LZ4F_localSaveDict(cctxPtr); + assert(0 <= realDictSize && realDictSize <= 64 KB); + cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize; + } + } + + /* keep tmpIn within limits */ + if (!(cctxPtr->prefs.autoFlush) /* no autoflush : there may be some data left within internal buffer */ + && (cctxPtr->tmpIn + blockSize) > (cctxPtr->tmpBuff + cctxPtr->maxBufferSize) ) /* not enough room to store next block */ + { + /* only preserve 64KB within internal buffer. Ensures there is enough room for next block. + * note: this situation necessarily implies lastBlockCompressed==fromTmpBuffer */ + int const realDictSize = LZ4F_localSaveDict(cctxPtr); + cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize; + assert((cctxPtr->tmpIn + blockSize) <= (cctxPtr->tmpBuff + cctxPtr->maxBufferSize)); + } + + /* some input data left, necessarily < blockSize */ + if (srcPtr < srcEnd) { + /* fill tmp buffer */ + size_t const sizeToCopy = (size_t)(srcEnd - srcPtr); + memcpy(cctxPtr->tmpIn, srcPtr, sizeToCopy); + cctxPtr->tmpInSize = sizeToCopy; + } + + if (cctxPtr->prefs.frameInfo.contentChecksumFlag == LZ4F_contentChecksumEnabled) + (void)XXH32_update(&(cctxPtr->xxh), srcBuffer, srcSize); + + cctxPtr->totalInSize += srcSize; + return (size_t)(dstPtr - dstStart); +} + +/*! LZ4F_compressUpdate() : + * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary. + * When successful, the function always entirely consumes @srcBuffer. + * src data is either buffered or compressed into @dstBuffer. + * If previously an uncompressed block was written, buffered data is flushed + * before appending compressed data is continued. + * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr). + * @compressOptionsPtr is optional : provide NULL to mean "default". + * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered. + * or an error code if it fails (which can be tested using LZ4F_isError()) + * After an error, the state is left in a UB state, and must be re-initialized. + */ +size_t LZ4F_compressUpdate(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_compressOptions_t* compressOptionsPtr) +{ + return LZ4F_compressUpdateImpl(cctxPtr, + dstBuffer, dstCapacity, + srcBuffer, srcSize, + compressOptionsPtr, LZ4B_COMPRESSED); +} + +/*! LZ4F_compressUpdate() : + * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary. + * When successful, the function always entirely consumes @srcBuffer. + * src data is either buffered or compressed into @dstBuffer. + * If previously an uncompressed block was written, buffered data is flushed + * before appending compressed data is continued. + * This is only supported when LZ4F_blockIndependent is used + * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr). + * @compressOptionsPtr is optional : provide NULL to mean "default". + * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered. + * or an error code if it fails (which can be tested using LZ4F_isError()) + * After an error, the state is left in a UB state, and must be re-initialized. + */ +size_t LZ4F_uncompressedUpdate(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_compressOptions_t* compressOptionsPtr) { + RETURN_ERROR_IF(cctxPtr->prefs.frameInfo.blockMode != LZ4F_blockIndependent, blockMode_invalid); + return LZ4F_compressUpdateImpl(cctxPtr, + dstBuffer, dstCapacity, + srcBuffer, srcSize, + compressOptionsPtr, LZ4B_UNCOMPRESSED); +} + + +/*! LZ4F_flush() : + * When compressed data must be sent immediately, without waiting for a block to be filled, + * invoke LZ4_flush(), which will immediately compress any remaining data stored within LZ4F_cctx. + * The result of the function is the number of bytes written into dstBuffer. + * It can be zero, this means there was no data left within LZ4F_cctx. + * The function outputs an error code if it fails (can be tested using LZ4F_isError()) + * LZ4F_compressOptions_t* is optional. NULL is a valid argument. + */ +size_t LZ4F_flush(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const LZ4F_compressOptions_t* compressOptionsPtr) +{ + BYTE* const dstStart = (BYTE*)dstBuffer; + BYTE* dstPtr = dstStart; + compressFunc_t compress; + + if (cctxPtr->tmpInSize == 0) return 0; /* nothing to flush */ + RETURN_ERROR_IF(cctxPtr->cStage != 1, compressionState_uninitialized); + RETURN_ERROR_IF(dstCapacity < (cctxPtr->tmpInSize + BHSize + BFSize), dstMaxSize_tooSmall); + (void)compressOptionsPtr; /* not useful (yet) */ + + /* select compression function */ + compress = LZ4F_selectCompression(cctxPtr->prefs.frameInfo.blockMode, cctxPtr->prefs.compressionLevel, cctxPtr->blockCompression); + + /* compress tmp buffer */ + dstPtr += LZ4F_makeBlock(dstPtr, + cctxPtr->tmpIn, cctxPtr->tmpInSize, + compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel, + cctxPtr->cdict, + cctxPtr->prefs.frameInfo.blockChecksumFlag); + assert(((void)"flush overflows dstBuffer!", (size_t)(dstPtr - dstStart) <= dstCapacity)); + + if (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) + cctxPtr->tmpIn += cctxPtr->tmpInSize; + cctxPtr->tmpInSize = 0; + + /* keep tmpIn within limits */ + if ((cctxPtr->tmpIn + cctxPtr->maxBlockSize) > (cctxPtr->tmpBuff + cctxPtr->maxBufferSize)) { /* necessarily LZ4F_blockLinked */ + int const realDictSize = LZ4F_localSaveDict(cctxPtr); + cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize; + } + + return (size_t)(dstPtr - dstStart); +} + + +/*! LZ4F_compressEnd() : + * When you want to properly finish the compressed frame, just call LZ4F_compressEnd(). + * It will flush whatever data remained within compressionContext (like LZ4_flush()) + * but also properly finalize the frame, with an endMark and an (optional) checksum. + * LZ4F_compressOptions_t structure is optional : you can provide NULL as argument. + * @return: the number of bytes written into dstBuffer (necessarily >= 4 (endMark size)) + * or an error code if it fails (can be tested using LZ4F_isError()) + * The context can then be used again to compress a new frame, starting with LZ4F_compressBegin(). + */ +size_t LZ4F_compressEnd(LZ4F_cctx* cctxPtr, + void* dstBuffer, size_t dstCapacity, + const LZ4F_compressOptions_t* compressOptionsPtr) +{ + BYTE* const dstStart = (BYTE*)dstBuffer; + BYTE* dstPtr = dstStart; + + size_t const flushSize = LZ4F_flush(cctxPtr, dstBuffer, dstCapacity, compressOptionsPtr); + DEBUGLOG(5,"LZ4F_compressEnd: dstCapacity=%u", (unsigned)dstCapacity); + FORWARD_IF_ERROR(flushSize); + dstPtr += flushSize; + + assert(flushSize <= dstCapacity); + dstCapacity -= flushSize; + + RETURN_ERROR_IF(dstCapacity < 4, dstMaxSize_tooSmall); + LZ4F_writeLE32(dstPtr, 0); + dstPtr += 4; /* endMark */ + + if (cctxPtr->prefs.frameInfo.contentChecksumFlag == LZ4F_contentChecksumEnabled) { + U32 const xxh = XXH32_digest(&(cctxPtr->xxh)); + RETURN_ERROR_IF(dstCapacity < 8, dstMaxSize_tooSmall); + DEBUGLOG(5,"Writing 32-bit content checksum"); + LZ4F_writeLE32(dstPtr, xxh); + dstPtr+=4; /* content Checksum */ + } + + cctxPtr->cStage = 0; /* state is now re-usable (with identical preferences) */ + cctxPtr->maxBufferSize = 0; /* reuse HC context */ + + if (cctxPtr->prefs.frameInfo.contentSize) { + if (cctxPtr->prefs.frameInfo.contentSize != cctxPtr->totalInSize) + RETURN_ERROR(frameSize_wrong); + } + + return (size_t)(dstPtr - dstStart); +} + + +/*-*************************************************** +* Frame Decompression +*****************************************************/ + +typedef enum { + dstage_getFrameHeader=0, dstage_storeFrameHeader, + dstage_init, + dstage_getBlockHeader, dstage_storeBlockHeader, + dstage_copyDirect, dstage_getBlockChecksum, + dstage_getCBlock, dstage_storeCBlock, + dstage_flushOut, + dstage_getSuffix, dstage_storeSuffix, + dstage_getSFrameSize, dstage_storeSFrameSize, + dstage_skipSkippable +} dStage_t; + +struct LZ4F_dctx_s { + LZ4F_CustomMem cmem; + LZ4F_frameInfo_t frameInfo; + U32 version; + dStage_t dStage; + U64 frameRemainingSize; + size_t maxBlockSize; + size_t maxBufferSize; + BYTE* tmpIn; + size_t tmpInSize; + size_t tmpInTarget; + BYTE* tmpOutBuffer; + const BYTE* dict; + size_t dictSize; + BYTE* tmpOut; + size_t tmpOutSize; + size_t tmpOutStart; + XXH32_state_t xxh; + XXH32_state_t blockChecksum; + int skipChecksum; + BYTE header[LZ4F_HEADER_SIZE_MAX]; +}; /* typedef'd to LZ4F_dctx in lz4frame.h */ + + +LZ4F_dctx* LZ4F_createDecompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version) +{ + LZ4F_dctx* const dctx = (LZ4F_dctx*)LZ4F_calloc(sizeof(LZ4F_dctx), customMem); + if (dctx == NULL) return NULL; + + dctx->cmem = customMem; + dctx->version = version; + return dctx; +} + +/*! LZ4F_createDecompressionContext() : + * Create a decompressionContext object, which will track all decompression operations. + * Provides a pointer to a fully allocated and initialized LZ4F_decompressionContext object. + * Object can later be released using LZ4F_freeDecompressionContext(). + * @return : if != 0, there was an error during context creation. + */ +LZ4F_errorCode_t +LZ4F_createDecompressionContext(LZ4F_dctx** LZ4F_decompressionContextPtr, unsigned versionNumber) +{ + assert(LZ4F_decompressionContextPtr != NULL); /* violation of narrow contract */ + RETURN_ERROR_IF(LZ4F_decompressionContextPtr == NULL, parameter_null); /* in case it nonetheless happen in production */ + + *LZ4F_decompressionContextPtr = LZ4F_createDecompressionContext_advanced(LZ4F_defaultCMem, versionNumber); + if (*LZ4F_decompressionContextPtr == NULL) { /* failed allocation */ + RETURN_ERROR(allocation_failed); + } + return LZ4F_OK_NoError; +} + +LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx) +{ + LZ4F_errorCode_t result = LZ4F_OK_NoError; + if (dctx != NULL) { /* can accept NULL input, like free() */ + result = (LZ4F_errorCode_t)dctx->dStage; + LZ4F_free(dctx->tmpIn, dctx->cmem); + LZ4F_free(dctx->tmpOutBuffer, dctx->cmem); + LZ4F_free(dctx, dctx->cmem); + } + return result; +} + + +/*==--- Streaming Decompression operations ---==*/ + +void LZ4F_resetDecompressionContext(LZ4F_dctx* dctx) +{ + dctx->dStage = dstage_getFrameHeader; + dctx->dict = NULL; + dctx->dictSize = 0; + dctx->skipChecksum = 0; +} + + +/*! LZ4F_decodeHeader() : + * input : `src` points at the **beginning of the frame** + * output : set internal values of dctx, such as + * dctx->frameInfo and dctx->dStage. + * Also allocates internal buffers. + * @return : nb Bytes read from src (necessarily <= srcSize) + * or an error code (testable with LZ4F_isError()) + */ +static size_t LZ4F_decodeHeader(LZ4F_dctx* dctx, const void* src, size_t srcSize) +{ + unsigned blockMode, blockChecksumFlag, contentSizeFlag, contentChecksumFlag, dictIDFlag, blockSizeID; + size_t frameHeaderSize; + const BYTE* srcPtr = (const BYTE*)src; + + DEBUGLOG(5, "LZ4F_decodeHeader"); + /* need to decode header to get frameInfo */ + RETURN_ERROR_IF(srcSize < minFHSize, frameHeader_incomplete); /* minimal frame header size */ + MEM_INIT(&(dctx->frameInfo), 0, sizeof(dctx->frameInfo)); + + /* special case : skippable frames */ + if ((LZ4F_readLE32(srcPtr) & 0xFFFFFFF0U) == LZ4F_MAGIC_SKIPPABLE_START) { + dctx->frameInfo.frameType = LZ4F_skippableFrame; + if (src == (void*)(dctx->header)) { + dctx->tmpInSize = srcSize; + dctx->tmpInTarget = 8; + dctx->dStage = dstage_storeSFrameSize; + return srcSize; + } else { + dctx->dStage = dstage_getSFrameSize; + return 4; + } } + + /* control magic number */ +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + if (LZ4F_readLE32(srcPtr) != LZ4F_MAGICNUMBER) { + DEBUGLOG(4, "frame header error : unknown magic number"); + RETURN_ERROR(frameType_unknown); + } +#endif + dctx->frameInfo.frameType = LZ4F_frame; + + /* Flags */ + { U32 const FLG = srcPtr[4]; + U32 const version = (FLG>>6) & _2BITS; + blockChecksumFlag = (FLG>>4) & _1BIT; + blockMode = (FLG>>5) & _1BIT; + contentSizeFlag = (FLG>>3) & _1BIT; + contentChecksumFlag = (FLG>>2) & _1BIT; + dictIDFlag = FLG & _1BIT; + /* validate */ + if (((FLG>>1)&_1BIT) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bit */ + if (version != 1) RETURN_ERROR(headerVersion_wrong); /* Version Number, only supported value */ + } + + /* Frame Header Size */ + frameHeaderSize = minFHSize + (contentSizeFlag?8:0) + (dictIDFlag?4:0); + + if (srcSize < frameHeaderSize) { + /* not enough input to fully decode frame header */ + if (srcPtr != dctx->header) + memcpy(dctx->header, srcPtr, srcSize); + dctx->tmpInSize = srcSize; + dctx->tmpInTarget = frameHeaderSize; + dctx->dStage = dstage_storeFrameHeader; + return srcSize; + } + + { U32 const BD = srcPtr[5]; + blockSizeID = (BD>>4) & _3BITS; + /* validate */ + if (((BD>>7)&_1BIT) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bit */ + if (blockSizeID < 4) RETURN_ERROR(maxBlockSize_invalid); /* 4-7 only supported values for the time being */ + if (((BD>>0)&_4BITS) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bits */ + } + + /* check header */ + assert(frameHeaderSize > 5); +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + { BYTE const HC = LZ4F_headerChecksum(srcPtr+4, frameHeaderSize-5); + RETURN_ERROR_IF(HC != srcPtr[frameHeaderSize-1], headerChecksum_invalid); + } +#endif + + /* save */ + dctx->frameInfo.blockMode = (LZ4F_blockMode_t)blockMode; + dctx->frameInfo.blockChecksumFlag = (LZ4F_blockChecksum_t)blockChecksumFlag; + dctx->frameInfo.contentChecksumFlag = (LZ4F_contentChecksum_t)contentChecksumFlag; + dctx->frameInfo.blockSizeID = (LZ4F_blockSizeID_t)blockSizeID; + dctx->maxBlockSize = LZ4F_getBlockSize((LZ4F_blockSizeID_t)blockSizeID); + if (contentSizeFlag) + dctx->frameRemainingSize = dctx->frameInfo.contentSize = LZ4F_readLE64(srcPtr+6); + if (dictIDFlag) + dctx->frameInfo.dictID = LZ4F_readLE32(srcPtr + frameHeaderSize - 5); + + dctx->dStage = dstage_init; + + return frameHeaderSize; +} + + +/*! LZ4F_headerSize() : + * @return : size of frame header + * or an error code, which can be tested using LZ4F_isError() + */ +size_t LZ4F_headerSize(const void* src, size_t srcSize) +{ + RETURN_ERROR_IF(src == NULL, srcPtr_wrong); + + /* minimal srcSize to determine header size */ + if (srcSize < LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH) + RETURN_ERROR(frameHeader_incomplete); + + /* special case : skippable frames */ + if ((LZ4F_readLE32(src) & 0xFFFFFFF0U) == LZ4F_MAGIC_SKIPPABLE_START) + return 8; + + /* control magic number */ +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + if (LZ4F_readLE32(src) != LZ4F_MAGICNUMBER) + RETURN_ERROR(frameType_unknown); +#endif + + /* Frame Header Size */ + { BYTE const FLG = ((const BYTE*)src)[4]; + U32 const contentSizeFlag = (FLG>>3) & _1BIT; + U32 const dictIDFlag = FLG & _1BIT; + return minFHSize + (contentSizeFlag?8:0) + (dictIDFlag?4:0); + } +} + +/*! LZ4F_getFrameInfo() : + * This function extracts frame parameters (max blockSize, frame checksum, etc.). + * Usage is optional. Objective is to provide relevant information for allocation purposes. + * This function works in 2 situations : + * - At the beginning of a new frame, in which case it will decode this information from `srcBuffer`, and start the decoding process. + * Amount of input data provided must be large enough to successfully decode the frame header. + * A header size is variable, but is guaranteed to be <= LZ4F_HEADER_SIZE_MAX bytes. It's possible to provide more input data than this minimum. + * - After decoding has been started. In which case, no input is read, frame parameters are extracted from dctx. + * The number of bytes consumed from srcBuffer will be updated within *srcSizePtr (necessarily <= original value). + * Decompression must resume from (srcBuffer + *srcSizePtr). + * @return : an hint about how many srcSize bytes LZ4F_decompress() expects for next call, + * or an error code which can be tested using LZ4F_isError() + * note 1 : in case of error, dctx is not modified. Decoding operations can resume from where they stopped. + * note 2 : frame parameters are *copied into* an already allocated LZ4F_frameInfo_t structure. + */ +LZ4F_errorCode_t LZ4F_getFrameInfo(LZ4F_dctx* dctx, + LZ4F_frameInfo_t* frameInfoPtr, + const void* srcBuffer, size_t* srcSizePtr) +{ + LZ4F_STATIC_ASSERT(dstage_getFrameHeader < dstage_storeFrameHeader); + if (dctx->dStage > dstage_storeFrameHeader) { + /* frameInfo already decoded */ + size_t o=0, i=0; + *srcSizePtr = 0; + *frameInfoPtr = dctx->frameInfo; + /* returns : recommended nb of bytes for LZ4F_decompress() */ + return LZ4F_decompress(dctx, NULL, &o, NULL, &i, NULL); + } else { + if (dctx->dStage == dstage_storeFrameHeader) { + /* frame decoding already started, in the middle of header => automatic fail */ + *srcSizePtr = 0; + RETURN_ERROR(frameDecoding_alreadyStarted); + } else { + size_t const hSize = LZ4F_headerSize(srcBuffer, *srcSizePtr); + if (LZ4F_isError(hSize)) { *srcSizePtr=0; return hSize; } + if (*srcSizePtr < hSize) { + *srcSizePtr=0; + RETURN_ERROR(frameHeader_incomplete); + } + + { size_t decodeResult = LZ4F_decodeHeader(dctx, srcBuffer, hSize); + if (LZ4F_isError(decodeResult)) { + *srcSizePtr = 0; + } else { + *srcSizePtr = decodeResult; + decodeResult = BHSize; /* block header size */ + } + *frameInfoPtr = dctx->frameInfo; + return decodeResult; + } } } +} + + +/* LZ4F_updateDict() : + * only used for LZ4F_blockLinked mode + * Condition : @dstPtr != NULL + */ +static void LZ4F_updateDict(LZ4F_dctx* dctx, + const BYTE* dstPtr, size_t dstSize, const BYTE* dstBufferStart, + unsigned withinTmp) +{ + assert(dstPtr != NULL); + if (dctx->dictSize==0) dctx->dict = (const BYTE*)dstPtr; /* will lead to prefix mode */ + assert(dctx->dict != NULL); + + if (dctx->dict + dctx->dictSize == dstPtr) { /* prefix mode, everything within dstBuffer */ + dctx->dictSize += dstSize; + return; + } + + assert(dstPtr >= dstBufferStart); + if ((size_t)(dstPtr - dstBufferStart) + dstSize >= 64 KB) { /* history in dstBuffer becomes large enough to become dictionary */ + dctx->dict = (const BYTE*)dstBufferStart; + dctx->dictSize = (size_t)(dstPtr - dstBufferStart) + dstSize; + return; + } + + assert(dstSize < 64 KB); /* if dstSize >= 64 KB, dictionary would be set into dstBuffer directly */ + + /* dstBuffer does not contain whole useful history (64 KB), so it must be saved within tmpOutBuffer */ + assert(dctx->tmpOutBuffer != NULL); + + if (withinTmp && (dctx->dict == dctx->tmpOutBuffer)) { /* continue history within tmpOutBuffer */ + /* withinTmp expectation : content of [dstPtr,dstSize] is same as [dict+dictSize,dstSize], so we just extend it */ + assert(dctx->dict + dctx->dictSize == dctx->tmpOut + dctx->tmpOutStart); + dctx->dictSize += dstSize; + return; + } + + if (withinTmp) { /* copy relevant dict portion in front of tmpOut within tmpOutBuffer */ + size_t const preserveSize = (size_t)(dctx->tmpOut - dctx->tmpOutBuffer); + size_t copySize = 64 KB - dctx->tmpOutSize; + const BYTE* const oldDictEnd = dctx->dict + dctx->dictSize - dctx->tmpOutStart; + if (dctx->tmpOutSize > 64 KB) copySize = 0; + if (copySize > preserveSize) copySize = preserveSize; + + memcpy(dctx->tmpOutBuffer + preserveSize - copySize, oldDictEnd - copySize, copySize); + + dctx->dict = dctx->tmpOutBuffer; + dctx->dictSize = preserveSize + dctx->tmpOutStart + dstSize; + return; + } + + if (dctx->dict == dctx->tmpOutBuffer) { /* copy dst into tmp to complete dict */ + if (dctx->dictSize + dstSize > dctx->maxBufferSize) { /* tmp buffer not large enough */ + size_t const preserveSize = 64 KB - dstSize; + memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - preserveSize, preserveSize); + dctx->dictSize = preserveSize; + } + memcpy(dctx->tmpOutBuffer + dctx->dictSize, dstPtr, dstSize); + dctx->dictSize += dstSize; + return; + } + + /* join dict & dest into tmp */ + { size_t preserveSize = 64 KB - dstSize; + if (preserveSize > dctx->dictSize) preserveSize = dctx->dictSize; + memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - preserveSize, preserveSize); + memcpy(dctx->tmpOutBuffer + preserveSize, dstPtr, dstSize); + dctx->dict = dctx->tmpOutBuffer; + dctx->dictSize = preserveSize + dstSize; + } +} + + +/*! LZ4F_decompress() : + * Call this function repetitively to regenerate compressed data in srcBuffer. + * The function will attempt to decode up to *srcSizePtr bytes from srcBuffer + * into dstBuffer of capacity *dstSizePtr. + * + * The number of bytes regenerated into dstBuffer will be provided within *dstSizePtr (necessarily <= original value). + * + * The number of bytes effectively read from srcBuffer will be provided within *srcSizePtr (necessarily <= original value). + * If number of bytes read is < number of bytes provided, then decompression operation is not complete. + * Remaining data will have to be presented again in a subsequent invocation. + * + * The function result is an hint of the better srcSize to use for next call to LZ4F_decompress. + * Schematically, it's the size of the current (or remaining) compressed block + header of next block. + * Respecting the hint provides a small boost to performance, since it allows less buffer shuffling. + * Note that this is just a hint, and it's always possible to any srcSize value. + * When a frame is fully decoded, @return will be 0. + * If decompression failed, @return is an error code which can be tested using LZ4F_isError(). + */ +size_t LZ4F_decompress(LZ4F_dctx* dctx, + void* dstBuffer, size_t* dstSizePtr, + const void* srcBuffer, size_t* srcSizePtr, + const LZ4F_decompressOptions_t* decompressOptionsPtr) +{ + LZ4F_decompressOptions_t optionsNull; + const BYTE* const srcStart = (const BYTE*)srcBuffer; + const BYTE* const srcEnd = srcStart + *srcSizePtr; + const BYTE* srcPtr = srcStart; + BYTE* const dstStart = (BYTE*)dstBuffer; + BYTE* const dstEnd = dstStart ? dstStart + *dstSizePtr : NULL; + BYTE* dstPtr = dstStart; + const BYTE* selectedIn = NULL; + unsigned doAnotherStage = 1; + size_t nextSrcSizeHint = 1; + + + DEBUGLOG(5, "LZ4F_decompress : %p,%u => %p,%u", + srcBuffer, (unsigned)*srcSizePtr, dstBuffer, (unsigned)*dstSizePtr); + if (dstBuffer == NULL) assert(*dstSizePtr == 0); + MEM_INIT(&optionsNull, 0, sizeof(optionsNull)); + if (decompressOptionsPtr==NULL) decompressOptionsPtr = &optionsNull; + *srcSizePtr = 0; + *dstSizePtr = 0; + assert(dctx != NULL); + dctx->skipChecksum |= (decompressOptionsPtr->skipChecksums != 0); /* once set, disable for the remainder of the frame */ + + /* behaves as a state machine */ + + while (doAnotherStage) { + + switch(dctx->dStage) + { + + case dstage_getFrameHeader: + DEBUGLOG(6, "dstage_getFrameHeader"); + if ((size_t)(srcEnd-srcPtr) >= maxFHSize) { /* enough to decode - shortcut */ + size_t const hSize = LZ4F_decodeHeader(dctx, srcPtr, (size_t)(srcEnd-srcPtr)); /* will update dStage appropriately */ + FORWARD_IF_ERROR(hSize); + srcPtr += hSize; + break; + } + dctx->tmpInSize = 0; + if (srcEnd-srcPtr == 0) return minFHSize; /* 0-size input */ + dctx->tmpInTarget = minFHSize; /* minimum size to decode header */ + dctx->dStage = dstage_storeFrameHeader; + /* fall-through */ + + case dstage_storeFrameHeader: + DEBUGLOG(6, "dstage_storeFrameHeader"); + { size_t const sizeToCopy = MIN(dctx->tmpInTarget - dctx->tmpInSize, (size_t)(srcEnd - srcPtr)); + memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy); + dctx->tmpInSize += sizeToCopy; + srcPtr += sizeToCopy; + } + if (dctx->tmpInSize < dctx->tmpInTarget) { + nextSrcSizeHint = (dctx->tmpInTarget - dctx->tmpInSize) + BHSize; /* rest of header + nextBlockHeader */ + doAnotherStage = 0; /* not enough src data, ask for some more */ + break; + } + FORWARD_IF_ERROR( LZ4F_decodeHeader(dctx, dctx->header, dctx->tmpInTarget) ); /* will update dStage appropriately */ + break; + + case dstage_init: + DEBUGLOG(6, "dstage_init"); + if (dctx->frameInfo.contentChecksumFlag) (void)XXH32_reset(&(dctx->xxh), 0); + /* internal buffers allocation */ + { size_t const bufferNeeded = dctx->maxBlockSize + + ((dctx->frameInfo.blockMode==LZ4F_blockLinked) ? 128 KB : 0); + if (bufferNeeded > dctx->maxBufferSize) { /* tmp buffers too small */ + dctx->maxBufferSize = 0; /* ensure allocation will be re-attempted on next entry*/ + LZ4F_free(dctx->tmpIn, dctx->cmem); + dctx->tmpIn = (BYTE*)LZ4F_malloc(dctx->maxBlockSize + BFSize /* block checksum */, dctx->cmem); + RETURN_ERROR_IF(dctx->tmpIn == NULL, allocation_failed); + LZ4F_free(dctx->tmpOutBuffer, dctx->cmem); + dctx->tmpOutBuffer= (BYTE*)LZ4F_malloc(bufferNeeded, dctx->cmem); + RETURN_ERROR_IF(dctx->tmpOutBuffer== NULL, allocation_failed); + dctx->maxBufferSize = bufferNeeded; + } } + dctx->tmpInSize = 0; + dctx->tmpInTarget = 0; + dctx->tmpOut = dctx->tmpOutBuffer; + dctx->tmpOutStart = 0; + dctx->tmpOutSize = 0; + + dctx->dStage = dstage_getBlockHeader; + /* fall-through */ + + case dstage_getBlockHeader: + if ((size_t)(srcEnd - srcPtr) >= BHSize) { + selectedIn = srcPtr; + srcPtr += BHSize; + } else { + /* not enough input to read cBlockSize field */ + dctx->tmpInSize = 0; + dctx->dStage = dstage_storeBlockHeader; + } + + if (dctx->dStage == dstage_storeBlockHeader) /* can be skipped */ + case dstage_storeBlockHeader: + { size_t const remainingInput = (size_t)(srcEnd - srcPtr); + size_t const wantedData = BHSize - dctx->tmpInSize; + size_t const sizeToCopy = MIN(wantedData, remainingInput); + memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy); + srcPtr += sizeToCopy; + dctx->tmpInSize += sizeToCopy; + + if (dctx->tmpInSize < BHSize) { /* not enough input for cBlockSize */ + nextSrcSizeHint = BHSize - dctx->tmpInSize; + doAnotherStage = 0; + break; + } + selectedIn = dctx->tmpIn; + } /* if (dctx->dStage == dstage_storeBlockHeader) */ + + /* decode block header */ + { U32 const blockHeader = LZ4F_readLE32(selectedIn); + size_t const nextCBlockSize = blockHeader & 0x7FFFFFFFU; + size_t const crcSize = dctx->frameInfo.blockChecksumFlag * BFSize; + if (blockHeader==0) { /* frameEnd signal, no more block */ + DEBUGLOG(5, "end of frame"); + dctx->dStage = dstage_getSuffix; + break; + } + if (nextCBlockSize > dctx->maxBlockSize) { + RETURN_ERROR(maxBlockSize_invalid); + } + if (blockHeader & LZ4F_BLOCKUNCOMPRESSED_FLAG) { + /* next block is uncompressed */ + dctx->tmpInTarget = nextCBlockSize; + DEBUGLOG(5, "next block is uncompressed (size %u)", (U32)nextCBlockSize); + if (dctx->frameInfo.blockChecksumFlag) { + (void)XXH32_reset(&dctx->blockChecksum, 0); + } + dctx->dStage = dstage_copyDirect; + break; + } + /* next block is a compressed block */ + dctx->tmpInTarget = nextCBlockSize + crcSize; + dctx->dStage = dstage_getCBlock; + if (dstPtr==dstEnd || srcPtr==srcEnd) { + nextSrcSizeHint = BHSize + nextCBlockSize + crcSize; + doAnotherStage = 0; + } + break; + } + + case dstage_copyDirect: /* uncompressed block */ + DEBUGLOG(6, "dstage_copyDirect"); + { size_t sizeToCopy; + if (dstPtr == NULL) { + sizeToCopy = 0; + } else { + size_t const minBuffSize = MIN((size_t)(srcEnd-srcPtr), (size_t)(dstEnd-dstPtr)); + sizeToCopy = MIN(dctx->tmpInTarget, minBuffSize); + memcpy(dstPtr, srcPtr, sizeToCopy); + if (!dctx->skipChecksum) { + if (dctx->frameInfo.blockChecksumFlag) { + (void)XXH32_update(&dctx->blockChecksum, srcPtr, sizeToCopy); + } + if (dctx->frameInfo.contentChecksumFlag) + (void)XXH32_update(&dctx->xxh, srcPtr, sizeToCopy); + } + if (dctx->frameInfo.contentSize) + dctx->frameRemainingSize -= sizeToCopy; + + /* history management (linked blocks only)*/ + if (dctx->frameInfo.blockMode == LZ4F_blockLinked) { + LZ4F_updateDict(dctx, dstPtr, sizeToCopy, dstStart, 0); + } } + + srcPtr += sizeToCopy; + dstPtr += sizeToCopy; + if (sizeToCopy == dctx->tmpInTarget) { /* all done */ + if (dctx->frameInfo.blockChecksumFlag) { + dctx->tmpInSize = 0; + dctx->dStage = dstage_getBlockChecksum; + } else + dctx->dStage = dstage_getBlockHeader; /* new block */ + break; + } + dctx->tmpInTarget -= sizeToCopy; /* need to copy more */ + } + nextSrcSizeHint = dctx->tmpInTarget + + +(dctx->frameInfo.blockChecksumFlag ? BFSize : 0) + + BHSize /* next header size */; + doAnotherStage = 0; + break; + + /* check block checksum for recently transferred uncompressed block */ + case dstage_getBlockChecksum: + DEBUGLOG(6, "dstage_getBlockChecksum"); + { const void* crcSrc; + if ((srcEnd-srcPtr >= 4) && (dctx->tmpInSize==0)) { + crcSrc = srcPtr; + srcPtr += 4; + } else { + size_t const stillToCopy = 4 - dctx->tmpInSize; + size_t const sizeToCopy = MIN(stillToCopy, (size_t)(srcEnd-srcPtr)); + memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy); + dctx->tmpInSize += sizeToCopy; + srcPtr += sizeToCopy; + if (dctx->tmpInSize < 4) { /* all input consumed */ + doAnotherStage = 0; + break; + } + crcSrc = dctx->header; + } + if (!dctx->skipChecksum) { + U32 const readCRC = LZ4F_readLE32(crcSrc); + U32 const calcCRC = XXH32_digest(&dctx->blockChecksum); +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + DEBUGLOG(6, "compare block checksum"); + if (readCRC != calcCRC) { + DEBUGLOG(4, "incorrect block checksum: %08X != %08X", + readCRC, calcCRC); + RETURN_ERROR(blockChecksum_invalid); + } +#else + (void)readCRC; + (void)calcCRC; +#endif + } } + dctx->dStage = dstage_getBlockHeader; /* new block */ + break; + + case dstage_getCBlock: + DEBUGLOG(6, "dstage_getCBlock"); + if ((size_t)(srcEnd-srcPtr) < dctx->tmpInTarget) { + dctx->tmpInSize = 0; + dctx->dStage = dstage_storeCBlock; + break; + } + /* input large enough to read full block directly */ + selectedIn = srcPtr; + srcPtr += dctx->tmpInTarget; + + if (0) /* always jump over next block */ + case dstage_storeCBlock: + { size_t const wantedData = dctx->tmpInTarget - dctx->tmpInSize; + size_t const inputLeft = (size_t)(srcEnd-srcPtr); + size_t const sizeToCopy = MIN(wantedData, inputLeft); + memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy); + dctx->tmpInSize += sizeToCopy; + srcPtr += sizeToCopy; + if (dctx->tmpInSize < dctx->tmpInTarget) { /* need more input */ + nextSrcSizeHint = (dctx->tmpInTarget - dctx->tmpInSize) + + (dctx->frameInfo.blockChecksumFlag ? BFSize : 0) + + BHSize /* next header size */; + doAnotherStage = 0; + break; + } + selectedIn = dctx->tmpIn; + } + + /* At this stage, input is large enough to decode a block */ + + /* First, decode and control block checksum if it exists */ + if (dctx->frameInfo.blockChecksumFlag) { + assert(dctx->tmpInTarget >= 4); + dctx->tmpInTarget -= 4; + assert(selectedIn != NULL); /* selectedIn is defined at this stage (either srcPtr, or dctx->tmpIn) */ + { U32 const readBlockCrc = LZ4F_readLE32(selectedIn + dctx->tmpInTarget); + U32 const calcBlockCrc = XXH32(selectedIn, dctx->tmpInTarget, 0); +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + RETURN_ERROR_IF(readBlockCrc != calcBlockCrc, blockChecksum_invalid); +#else + (void)readBlockCrc; + (void)calcBlockCrc; +#endif + } } + + /* decode directly into destination buffer if there is enough room */ + if ( ((size_t)(dstEnd-dstPtr) >= dctx->maxBlockSize) + /* unless the dictionary is stored in tmpOut: + * in which case it's faster to decode within tmpOut + * to benefit from prefix speedup */ + && !(dctx->dict!= NULL && (const BYTE*)dctx->dict + dctx->dictSize == dctx->tmpOut) ) + { + const char* dict = (const char*)dctx->dict; + size_t dictSize = dctx->dictSize; + int decodedSize; + assert(dstPtr != NULL); + if (dict && dictSize > 1 GB) { + /* overflow control : dctx->dictSize is an int, avoid truncation / sign issues */ + dict += dictSize - 64 KB; + dictSize = 64 KB; + } + decodedSize = LZ4_decompress_safe_usingDict( + (const char*)selectedIn, (char*)dstPtr, + (int)dctx->tmpInTarget, (int)dctx->maxBlockSize, + dict, (int)dictSize); + RETURN_ERROR_IF(decodedSize < 0, decompressionFailed); + if ((dctx->frameInfo.contentChecksumFlag) && (!dctx->skipChecksum)) + XXH32_update(&(dctx->xxh), dstPtr, (size_t)decodedSize); + if (dctx->frameInfo.contentSize) + dctx->frameRemainingSize -= (size_t)decodedSize; + + /* dictionary management */ + if (dctx->frameInfo.blockMode==LZ4F_blockLinked) { + LZ4F_updateDict(dctx, dstPtr, (size_t)decodedSize, dstStart, 0); + } + + dstPtr += decodedSize; + dctx->dStage = dstage_getBlockHeader; /* end of block, let's get another one */ + break; + } + + /* not enough place into dst : decode into tmpOut */ + + /* manage dictionary */ + if (dctx->frameInfo.blockMode == LZ4F_blockLinked) { + if (dctx->dict == dctx->tmpOutBuffer) { + /* truncate dictionary to 64 KB if too big */ + if (dctx->dictSize > 128 KB) { + memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - 64 KB, 64 KB); + dctx->dictSize = 64 KB; + } + dctx->tmpOut = dctx->tmpOutBuffer + dctx->dictSize; + } else { /* dict not within tmpOut */ + size_t const reservedDictSpace = MIN(dctx->dictSize, 64 KB); + dctx->tmpOut = dctx->tmpOutBuffer + reservedDictSpace; + } } + + /* Decode block into tmpOut */ + { const char* dict = (const char*)dctx->dict; + size_t dictSize = dctx->dictSize; + int decodedSize; + if (dict && dictSize > 1 GB) { + /* the dictSize param is an int, avoid truncation / sign issues */ + dict += dictSize - 64 KB; + dictSize = 64 KB; + } + decodedSize = LZ4_decompress_safe_usingDict( + (const char*)selectedIn, (char*)dctx->tmpOut, + (int)dctx->tmpInTarget, (int)dctx->maxBlockSize, + dict, (int)dictSize); + RETURN_ERROR_IF(decodedSize < 0, decompressionFailed); + if (dctx->frameInfo.contentChecksumFlag && !dctx->skipChecksum) + XXH32_update(&(dctx->xxh), dctx->tmpOut, (size_t)decodedSize); + if (dctx->frameInfo.contentSize) + dctx->frameRemainingSize -= (size_t)decodedSize; + dctx->tmpOutSize = (size_t)decodedSize; + dctx->tmpOutStart = 0; + dctx->dStage = dstage_flushOut; + } + /* fall-through */ + + case dstage_flushOut: /* flush decoded data from tmpOut to dstBuffer */ + DEBUGLOG(6, "dstage_flushOut"); + if (dstPtr != NULL) { + size_t const sizeToCopy = MIN(dctx->tmpOutSize - dctx->tmpOutStart, (size_t)(dstEnd-dstPtr)); + memcpy(dstPtr, dctx->tmpOut + dctx->tmpOutStart, sizeToCopy); + + /* dictionary management */ + if (dctx->frameInfo.blockMode == LZ4F_blockLinked) + LZ4F_updateDict(dctx, dstPtr, sizeToCopy, dstStart, 1 /*withinTmp*/); + + dctx->tmpOutStart += sizeToCopy; + dstPtr += sizeToCopy; + } + if (dctx->tmpOutStart == dctx->tmpOutSize) { /* all flushed */ + dctx->dStage = dstage_getBlockHeader; /* get next block */ + break; + } + /* could not flush everything : stop there, just request a block header */ + doAnotherStage = 0; + nextSrcSizeHint = BHSize; + break; + + case dstage_getSuffix: + RETURN_ERROR_IF(dctx->frameRemainingSize, frameSize_wrong); /* incorrect frame size decoded */ + if (!dctx->frameInfo.contentChecksumFlag) { /* no checksum, frame is completed */ + nextSrcSizeHint = 0; + LZ4F_resetDecompressionContext(dctx); + doAnotherStage = 0; + break; + } + if ((srcEnd - srcPtr) < 4) { /* not enough size for entire CRC */ + dctx->tmpInSize = 0; + dctx->dStage = dstage_storeSuffix; + } else { + selectedIn = srcPtr; + srcPtr += 4; + } + + if (dctx->dStage == dstage_storeSuffix) /* can be skipped */ + case dstage_storeSuffix: + { size_t const remainingInput = (size_t)(srcEnd - srcPtr); + size_t const wantedData = 4 - dctx->tmpInSize; + size_t const sizeToCopy = MIN(wantedData, remainingInput); + memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy); + srcPtr += sizeToCopy; + dctx->tmpInSize += sizeToCopy; + if (dctx->tmpInSize < 4) { /* not enough input to read complete suffix */ + nextSrcSizeHint = 4 - dctx->tmpInSize; + doAnotherStage=0; + break; + } + selectedIn = dctx->tmpIn; + } /* if (dctx->dStage == dstage_storeSuffix) */ + + /* case dstage_checkSuffix: */ /* no direct entry, avoid initialization risks */ + if (!dctx->skipChecksum) { + U32 const readCRC = LZ4F_readLE32(selectedIn); + U32 const resultCRC = XXH32_digest(&(dctx->xxh)); +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + RETURN_ERROR_IF(readCRC != resultCRC, contentChecksum_invalid); +#else + (void)readCRC; + (void)resultCRC; +#endif + } + nextSrcSizeHint = 0; + LZ4F_resetDecompressionContext(dctx); + doAnotherStage = 0; + break; + + case dstage_getSFrameSize: + if ((srcEnd - srcPtr) >= 4) { + selectedIn = srcPtr; + srcPtr += 4; + } else { + /* not enough input to read cBlockSize field */ + dctx->tmpInSize = 4; + dctx->tmpInTarget = 8; + dctx->dStage = dstage_storeSFrameSize; + } + + if (dctx->dStage == dstage_storeSFrameSize) + case dstage_storeSFrameSize: + { size_t const sizeToCopy = MIN(dctx->tmpInTarget - dctx->tmpInSize, + (size_t)(srcEnd - srcPtr) ); + memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy); + srcPtr += sizeToCopy; + dctx->tmpInSize += sizeToCopy; + if (dctx->tmpInSize < dctx->tmpInTarget) { + /* not enough input to get full sBlockSize; wait for more */ + nextSrcSizeHint = dctx->tmpInTarget - dctx->tmpInSize; + doAnotherStage = 0; + break; + } + selectedIn = dctx->header + 4; + } /* if (dctx->dStage == dstage_storeSFrameSize) */ + + /* case dstage_decodeSFrameSize: */ /* no direct entry */ + { size_t const SFrameSize = LZ4F_readLE32(selectedIn); + dctx->frameInfo.contentSize = SFrameSize; + dctx->tmpInTarget = SFrameSize; + dctx->dStage = dstage_skipSkippable; + break; + } + + case dstage_skipSkippable: + { size_t const skipSize = MIN(dctx->tmpInTarget, (size_t)(srcEnd-srcPtr)); + srcPtr += skipSize; + dctx->tmpInTarget -= skipSize; + doAnotherStage = 0; + nextSrcSizeHint = dctx->tmpInTarget; + if (nextSrcSizeHint) break; /* still more to skip */ + /* frame fully skipped : prepare context for a new frame */ + LZ4F_resetDecompressionContext(dctx); + break; + } + } /* switch (dctx->dStage) */ + } /* while (doAnotherStage) */ + + /* preserve history within tmpOut whenever necessary */ + LZ4F_STATIC_ASSERT((unsigned)dstage_init == 2); + if ( (dctx->frameInfo.blockMode==LZ4F_blockLinked) /* next block will use up to 64KB from previous ones */ + && (dctx->dict != dctx->tmpOutBuffer) /* dictionary is not already within tmp */ + && (dctx->dict != NULL) /* dictionary exists */ + && (!decompressOptionsPtr->stableDst) /* cannot rely on dst data to remain there for next call */ + && ((unsigned)(dctx->dStage)-2 < (unsigned)(dstage_getSuffix)-2) ) /* valid stages : [init ... getSuffix[ */ + { + if (dctx->dStage == dstage_flushOut) { + size_t const preserveSize = (size_t)(dctx->tmpOut - dctx->tmpOutBuffer); + size_t copySize = 64 KB - dctx->tmpOutSize; + const BYTE* oldDictEnd = dctx->dict + dctx->dictSize - dctx->tmpOutStart; + if (dctx->tmpOutSize > 64 KB) copySize = 0; + if (copySize > preserveSize) copySize = preserveSize; + assert(dctx->tmpOutBuffer != NULL); + + memcpy(dctx->tmpOutBuffer + preserveSize - copySize, oldDictEnd - copySize, copySize); + + dctx->dict = dctx->tmpOutBuffer; + dctx->dictSize = preserveSize + dctx->tmpOutStart; + } else { + const BYTE* const oldDictEnd = dctx->dict + dctx->dictSize; + size_t const newDictSize = MIN(dctx->dictSize, 64 KB); + + memcpy(dctx->tmpOutBuffer, oldDictEnd - newDictSize, newDictSize); + + dctx->dict = dctx->tmpOutBuffer; + dctx->dictSize = newDictSize; + dctx->tmpOut = dctx->tmpOutBuffer + newDictSize; + } + } + + *srcSizePtr = (size_t)(srcPtr - srcStart); + *dstSizePtr = (size_t)(dstPtr - dstStart); + return nextSrcSizeHint; +} + +/*! LZ4F_decompress_usingDict() : + * Same as LZ4F_decompress(), using a predefined dictionary. + * Dictionary is used "in place", without any preprocessing. + * It must remain accessible throughout the entire frame decoding. + */ +size_t LZ4F_decompress_usingDict(LZ4F_dctx* dctx, + void* dstBuffer, size_t* dstSizePtr, + const void* srcBuffer, size_t* srcSizePtr, + const void* dict, size_t dictSize, + const LZ4F_decompressOptions_t* decompressOptionsPtr) +{ + if (dctx->dStage <= dstage_init) { + dctx->dict = (const BYTE*)dict; + dctx->dictSize = dictSize; + } + return LZ4F_decompress(dctx, dstBuffer, dstSizePtr, + srcBuffer, srcSizePtr, + decompressOptionsPtr); +} diff --git a/cbits/lz4frame.h b/cbits/lz4frame.h new file mode 100644 --- /dev/null +++ b/cbits/lz4frame.h @@ -0,0 +1,692 @@ +/* + LZ4F - LZ4-Frame library + Header File + Copyright (C) 2011-2020, Yann Collet. + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + You can contact the author at : + - LZ4 source repository : https://github.com/lz4/lz4 + - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c +*/ + +/* LZ4F is a stand-alone API able to create and decode LZ4 frames + * conformant with specification v1.6.1 in doc/lz4_Frame_format.md . + * Generated frames are compatible with `lz4` CLI. + * + * LZ4F also offers streaming capabilities. + * + * lz4.h is not required when using lz4frame.h, + * except to extract common constants such as LZ4_VERSION_NUMBER. + * */ + +#ifndef LZ4F_H_09782039843 +#define LZ4F_H_09782039843 + +#if defined (__cplusplus) +extern "C" { +#endif + +/* --- Dependency --- */ +#include /* size_t */ + + +/** + * Introduction + * + * lz4frame.h implements LZ4 frame specification: see doc/lz4_Frame_format.md . + * LZ4 Frames are compatible with `lz4` CLI, + * and designed to be interoperable with any system. +**/ + +/*-*************************************************************** + * Compiler specifics + *****************************************************************/ +/* LZ4_DLL_EXPORT : + * Enable exporting of functions when building a Windows DLL + * LZ4FLIB_VISIBILITY : + * Control library symbols visibility. + */ +#ifndef LZ4FLIB_VISIBILITY +# if defined(__GNUC__) && (__GNUC__ >= 4) +# define LZ4FLIB_VISIBILITY __attribute__ ((visibility ("default"))) +# else +# define LZ4FLIB_VISIBILITY +# endif +#endif +#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1) +# define LZ4FLIB_API __declspec(dllexport) LZ4FLIB_VISIBILITY +#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1) +# define LZ4FLIB_API __declspec(dllimport) LZ4FLIB_VISIBILITY +#else +# define LZ4FLIB_API LZ4FLIB_VISIBILITY +#endif + +#ifdef LZ4F_DISABLE_DEPRECATE_WARNINGS +# define LZ4F_DEPRECATE(x) x +#else +# if defined(_MSC_VER) +# define LZ4F_DEPRECATE(x) x /* __declspec(deprecated) x - only works with C++ */ +# elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ >= 6)) +# define LZ4F_DEPRECATE(x) x __attribute__((deprecated)) +# else +# define LZ4F_DEPRECATE(x) x /* no deprecation warning for this compiler */ +# endif +#endif + + +/*-************************************ + * Error management + **************************************/ +typedef size_t LZ4F_errorCode_t; + +LZ4FLIB_API unsigned LZ4F_isError(LZ4F_errorCode_t code); /**< tells when a function result is an error code */ +LZ4FLIB_API const char* LZ4F_getErrorName(LZ4F_errorCode_t code); /**< return error code string; for debugging */ + + +/*-************************************ + * Frame compression types + ************************************* */ +/* #define LZ4F_ENABLE_OBSOLETE_ENUMS // uncomment to enable obsolete enums */ +#ifdef LZ4F_ENABLE_OBSOLETE_ENUMS +# define LZ4F_OBSOLETE_ENUM(x) , LZ4F_DEPRECATE(x) = LZ4F_##x +#else +# define LZ4F_OBSOLETE_ENUM(x) +#endif + +/* The larger the block size, the (slightly) better the compression ratio, + * though there are diminishing returns. + * Larger blocks also increase memory usage on both compression and decompression sides. + */ +typedef enum { + LZ4F_default=0, + LZ4F_max64KB=4, + LZ4F_max256KB=5, + LZ4F_max1MB=6, + LZ4F_max4MB=7 + LZ4F_OBSOLETE_ENUM(max64KB) + LZ4F_OBSOLETE_ENUM(max256KB) + LZ4F_OBSOLETE_ENUM(max1MB) + LZ4F_OBSOLETE_ENUM(max4MB) +} LZ4F_blockSizeID_t; + +/* Linked blocks sharply reduce inefficiencies when using small blocks, + * they compress better. + * However, some LZ4 decoders are only compatible with independent blocks */ +typedef enum { + LZ4F_blockLinked=0, + LZ4F_blockIndependent + LZ4F_OBSOLETE_ENUM(blockLinked) + LZ4F_OBSOLETE_ENUM(blockIndependent) +} LZ4F_blockMode_t; + +typedef enum { + LZ4F_noContentChecksum=0, + LZ4F_contentChecksumEnabled + LZ4F_OBSOLETE_ENUM(noContentChecksum) + LZ4F_OBSOLETE_ENUM(contentChecksumEnabled) +} LZ4F_contentChecksum_t; + +typedef enum { + LZ4F_noBlockChecksum=0, + LZ4F_blockChecksumEnabled +} LZ4F_blockChecksum_t; + +typedef enum { + LZ4F_frame=0, + LZ4F_skippableFrame + LZ4F_OBSOLETE_ENUM(skippableFrame) +} LZ4F_frameType_t; + +#ifdef LZ4F_ENABLE_OBSOLETE_ENUMS +typedef LZ4F_blockSizeID_t blockSizeID_t; +typedef LZ4F_blockMode_t blockMode_t; +typedef LZ4F_frameType_t frameType_t; +typedef LZ4F_contentChecksum_t contentChecksum_t; +#endif + +/*! LZ4F_frameInfo_t : + * makes it possible to set or read frame parameters. + * Structure must be first init to 0, using memset() or LZ4F_INIT_FRAMEINFO, + * setting all parameters to default. + * It's then possible to update selectively some parameters */ +typedef struct { + LZ4F_blockSizeID_t blockSizeID; /* max64KB, max256KB, max1MB, max4MB; 0 == default */ + LZ4F_blockMode_t blockMode; /* LZ4F_blockLinked, LZ4F_blockIndependent; 0 == default */ + LZ4F_contentChecksum_t contentChecksumFlag; /* 1: frame terminated with 32-bit checksum of decompressed data; 0: disabled (default) */ + LZ4F_frameType_t frameType; /* read-only field : LZ4F_frame or LZ4F_skippableFrame */ + unsigned long long contentSize; /* Size of uncompressed content ; 0 == unknown */ + unsigned dictID; /* Dictionary ID, sent by compressor to help decoder select correct dictionary; 0 == no dictID provided */ + LZ4F_blockChecksum_t blockChecksumFlag; /* 1: each block followed by a checksum of block's compressed data; 0: disabled (default) */ +} LZ4F_frameInfo_t; + +#define LZ4F_INIT_FRAMEINFO { LZ4F_default, LZ4F_blockLinked, LZ4F_noContentChecksum, LZ4F_frame, 0ULL, 0U, LZ4F_noBlockChecksum } /* v1.8.3+ */ + +/*! LZ4F_preferences_t : + * makes it possible to supply advanced compression instructions to streaming interface. + * Structure must be first init to 0, using memset() or LZ4F_INIT_PREFERENCES, + * setting all parameters to default. + * All reserved fields must be set to zero. */ +typedef struct { + LZ4F_frameInfo_t frameInfo; + int compressionLevel; /* 0: default (fast mode); values > LZ4HC_CLEVEL_MAX count as LZ4HC_CLEVEL_MAX; values < 0 trigger "fast acceleration" */ + unsigned autoFlush; /* 1: always flush; reduces usage of internal buffers */ + unsigned favorDecSpeed; /* 1: parser favors decompression speed vs compression ratio. Only works for high compression modes (>= LZ4HC_CLEVEL_OPT_MIN) */ /* v1.8.2+ */ + unsigned reserved[3]; /* must be zero for forward compatibility */ +} LZ4F_preferences_t; + +#define LZ4F_INIT_PREFERENCES { LZ4F_INIT_FRAMEINFO, 0, 0u, 0u, { 0u, 0u, 0u } } /* v1.8.3+ */ + + +/*-********************************* +* Simple compression function +***********************************/ + +LZ4FLIB_API int LZ4F_compressionLevel_max(void); /* v1.8.0+ */ + +/*! LZ4F_compressFrameBound() : + * Returns the maximum possible compressed size with LZ4F_compressFrame() given srcSize and preferences. + * `preferencesPtr` is optional. It can be replaced by NULL, in which case, the function will assume default preferences. + * Note : this result is only usable with LZ4F_compressFrame(). + * It may also be relevant to LZ4F_compressUpdate() _only if_ no flush() operation is ever performed. + */ +LZ4FLIB_API size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr); + +/*! LZ4F_compressFrame() : + * Compress an entire srcBuffer into a valid LZ4 frame. + * dstCapacity MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr). + * The LZ4F_preferences_t structure is optional : you can provide NULL as argument. All preferences will be set to default. + * @return : number of bytes written into dstBuffer. + * or an error code if it fails (can be tested using LZ4F_isError()) + */ +LZ4FLIB_API size_t LZ4F_compressFrame(void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_preferences_t* preferencesPtr); + + +/*-*********************************** +* Advanced compression functions +*************************************/ +typedef struct LZ4F_cctx_s LZ4F_cctx; /* incomplete type */ +typedef LZ4F_cctx* LZ4F_compressionContext_t; /* for compatibility with older APIs, prefer using LZ4F_cctx */ + +typedef struct { + unsigned stableSrc; /* 1 == src content will remain present on future calls to LZ4F_compress(); skip copying src content within tmp buffer */ + unsigned reserved[3]; +} LZ4F_compressOptions_t; + +/*--- Resource Management ---*/ + +#define LZ4F_VERSION 100 /* This number can be used to check for an incompatible API breaking change */ +LZ4FLIB_API unsigned LZ4F_getVersion(void); + +/*! LZ4F_createCompressionContext() : + * The first thing to do is to create a compressionContext object, + * which will keep track of operation state during streaming compression. + * This is achieved using LZ4F_createCompressionContext(), which takes as argument a version, + * and a pointer to LZ4F_cctx*, to write the resulting pointer into. + * @version provided MUST be LZ4F_VERSION. It is intended to track potential version mismatch, notably when using DLL. + * The function provides a pointer to a fully allocated LZ4F_cctx object. + * @cctxPtr MUST be != NULL. + * If @return != zero, context creation failed. + * A created compression context can be employed multiple times for consecutive streaming operations. + * Once all streaming compression jobs are completed, + * the state object can be released using LZ4F_freeCompressionContext(). + * Note1 : LZ4F_freeCompressionContext() is always successful. Its return value can be ignored. + * Note2 : LZ4F_freeCompressionContext() works fine with NULL input pointers (do nothing). +**/ +LZ4FLIB_API LZ4F_errorCode_t LZ4F_createCompressionContext(LZ4F_cctx** cctxPtr, unsigned version); +LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_cctx* cctx); + + +/*---- Compression ----*/ + +#define LZ4F_HEADER_SIZE_MIN 7 /* LZ4 Frame header size can vary, depending on selected parameters */ +#define LZ4F_HEADER_SIZE_MAX 19 + +/* Size in bytes of a block header in little-endian format. Highest bit indicates if block data is uncompressed */ +#define LZ4F_BLOCK_HEADER_SIZE 4 + +/* Size in bytes of a block checksum footer in little-endian format. */ +#define LZ4F_BLOCK_CHECKSUM_SIZE 4 + +/* Size in bytes of the content checksum. */ +#define LZ4F_CONTENT_CHECKSUM_SIZE 4 + +/*! LZ4F_compressBegin() : + * will write the frame header into dstBuffer. + * dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes. + * `prefsPtr` is optional : you can provide NULL as argument, all preferences will then be set to default. + * @return : number of bytes written into dstBuffer for the header + * or an error code (which can be tested using LZ4F_isError()) + */ +LZ4FLIB_API size_t LZ4F_compressBegin(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const LZ4F_preferences_t* prefsPtr); + +/*! LZ4F_compressBound() : + * Provides minimum dstCapacity required to guarantee success of + * LZ4F_compressUpdate(), given a srcSize and preferences, for a worst case scenario. + * When srcSize==0, LZ4F_compressBound() provides an upper bound for LZ4F_flush() and LZ4F_compressEnd() instead. + * Note that the result is only valid for a single invocation of LZ4F_compressUpdate(). + * When invoking LZ4F_compressUpdate() multiple times, + * if the output buffer is gradually filled up instead of emptied and re-used from its start, + * one must check if there is enough remaining capacity before each invocation, using LZ4F_compressBound(). + * @return is always the same for a srcSize and prefsPtr. + * prefsPtr is optional : when NULL is provided, preferences will be set to cover worst case scenario. + * tech details : + * @return if automatic flushing is not enabled, includes the possibility that internal buffer might already be filled by up to (blockSize-1) bytes. + * It also includes frame footer (ending + checksum), since it might be generated by LZ4F_compressEnd(). + * @return doesn't include frame header, as it was already generated by LZ4F_compressBegin(). + */ +LZ4FLIB_API size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* prefsPtr); + +/*! LZ4F_compressUpdate() : + * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary. + * Important rule: dstCapacity MUST be large enough to ensure operation success even in worst case situations. + * This value is provided by LZ4F_compressBound(). + * If this condition is not respected, LZ4F_compress() will fail (result is an errorCode). + * After an error, the state is left in a UB state, and must be re-initialized or freed. + * If previously an uncompressed block was written, buffered data is flushed + * before appending compressed data is continued. + * `cOptPtr` is optional : NULL can be provided, in which case all options are set to default. + * @return : number of bytes written into `dstBuffer` (it can be zero, meaning input data was just buffered). + * or an error code if it fails (which can be tested using LZ4F_isError()) + */ +LZ4FLIB_API size_t LZ4F_compressUpdate(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_compressOptions_t* cOptPtr); + +/*! LZ4F_flush() : + * When data must be generated and sent immediately, without waiting for a block to be completely filled, + * it's possible to call LZ4_flush(). It will immediately compress any data buffered within cctx. + * `dstCapacity` must be large enough to ensure the operation will be successful. + * `cOptPtr` is optional : it's possible to provide NULL, all options will be set to default. + * @return : nb of bytes written into dstBuffer (can be zero, when there is no data stored within cctx) + * or an error code if it fails (which can be tested using LZ4F_isError()) + * Note : LZ4F_flush() is guaranteed to be successful when dstCapacity >= LZ4F_compressBound(0, prefsPtr). + */ +LZ4FLIB_API size_t LZ4F_flush(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const LZ4F_compressOptions_t* cOptPtr); + +/*! LZ4F_compressEnd() : + * To properly finish an LZ4 frame, invoke LZ4F_compressEnd(). + * It will flush whatever data remained within `cctx` (like LZ4_flush()) + * and properly finalize the frame, with an endMark and a checksum. + * `cOptPtr` is optional : NULL can be provided, in which case all options will be set to default. + * @return : nb of bytes written into dstBuffer, necessarily >= 4 (endMark), + * or an error code if it fails (which can be tested using LZ4F_isError()) + * Note : LZ4F_compressEnd() is guaranteed to be successful when dstCapacity >= LZ4F_compressBound(0, prefsPtr). + * A successful call to LZ4F_compressEnd() makes `cctx` available again for another compression task. + */ +LZ4FLIB_API size_t LZ4F_compressEnd(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const LZ4F_compressOptions_t* cOptPtr); + + +/*-********************************* +* Decompression functions +***********************************/ +typedef struct LZ4F_dctx_s LZ4F_dctx; /* incomplete type */ +typedef LZ4F_dctx* LZ4F_decompressionContext_t; /* compatibility with previous API versions */ + +typedef struct { + unsigned stableDst; /* pledges that last 64KB decompressed data will remain available unmodified between invocations. + * This optimization skips storage operations in tmp buffers. */ + unsigned skipChecksums; /* disable checksum calculation and verification, even when one is present in frame, to save CPU time. + * Setting this option to 1 once disables all checksums for the rest of the frame. */ + unsigned reserved1; /* must be set to zero for forward compatibility */ + unsigned reserved0; /* idem */ +} LZ4F_decompressOptions_t; + + +/* Resource management */ + +/*! LZ4F_createDecompressionContext() : + * Create an LZ4F_dctx object, to track all decompression operations. + * @version provided MUST be LZ4F_VERSION. + * @dctxPtr MUST be valid. + * The function fills @dctxPtr with the value of a pointer to an allocated and initialized LZ4F_dctx object. + * The @return is an errorCode, which can be tested using LZ4F_isError(). + * dctx memory can be released using LZ4F_freeDecompressionContext(); + * Result of LZ4F_freeDecompressionContext() indicates current state of decompressionContext when being released. + * That is, it should be == 0 if decompression has been completed fully and correctly. + */ +LZ4FLIB_API LZ4F_errorCode_t LZ4F_createDecompressionContext(LZ4F_dctx** dctxPtr, unsigned version); +LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx); + + +/*-*********************************** +* Streaming decompression functions +*************************************/ + +#define LZ4F_MAGICNUMBER 0x184D2204U +#define LZ4F_MAGIC_SKIPPABLE_START 0x184D2A50U +#define LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH 5 + +/*! LZ4F_headerSize() : v1.9.0+ + * Provide the header size of a frame starting at `src`. + * `srcSize` must be >= LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH, + * which is enough to decode the header length. + * @return : size of frame header + * or an error code, which can be tested using LZ4F_isError() + * note : Frame header size is variable, but is guaranteed to be + * >= LZ4F_HEADER_SIZE_MIN bytes, and <= LZ4F_HEADER_SIZE_MAX bytes. + */ +LZ4FLIB_API size_t LZ4F_headerSize(const void* src, size_t srcSize); + +/*! LZ4F_getFrameInfo() : + * This function extracts frame parameters (max blockSize, dictID, etc.). + * Its usage is optional: user can also invoke LZ4F_decompress() directly. + * + * Extracted information will fill an existing LZ4F_frameInfo_t structure. + * This can be useful for allocation and dictionary identification purposes. + * + * LZ4F_getFrameInfo() can work in the following situations : + * + * 1) At the beginning of a new frame, before any invocation of LZ4F_decompress(). + * It will decode header from `srcBuffer`, + * consuming the header and starting the decoding process. + * + * Input size must be large enough to contain the full frame header. + * Frame header size can be known beforehand by LZ4F_headerSize(). + * Frame header size is variable, but is guaranteed to be >= LZ4F_HEADER_SIZE_MIN bytes, + * and not more than <= LZ4F_HEADER_SIZE_MAX bytes. + * Hence, blindly providing LZ4F_HEADER_SIZE_MAX bytes or more will always work. + * It's allowed to provide more input data than the header size, + * LZ4F_getFrameInfo() will only consume the header. + * + * If input size is not large enough, + * aka if it's smaller than header size, + * function will fail and return an error code. + * + * 2) After decoding has been started, + * it's possible to invoke LZ4F_getFrameInfo() anytime + * to extract already decoded frame parameters stored within dctx. + * + * Note that, if decoding has barely started, + * and not yet read enough information to decode the header, + * LZ4F_getFrameInfo() will fail. + * + * The number of bytes consumed from srcBuffer will be updated in *srcSizePtr (necessarily <= original value). + * LZ4F_getFrameInfo() only consumes bytes when decoding has not yet started, + * and when decoding the header has been successful. + * Decompression must then resume from (srcBuffer + *srcSizePtr). + * + * @return : a hint about how many srcSize bytes LZ4F_decompress() expects for next call, + * or an error code which can be tested using LZ4F_isError(). + * note 1 : in case of error, dctx is not modified. Decoding operation can resume from beginning safely. + * note 2 : frame parameters are *copied into* an already allocated LZ4F_frameInfo_t structure. + */ +LZ4FLIB_API size_t +LZ4F_getFrameInfo(LZ4F_dctx* dctx, + LZ4F_frameInfo_t* frameInfoPtr, + const void* srcBuffer, size_t* srcSizePtr); + +/*! LZ4F_decompress() : + * Call this function repetitively to regenerate data compressed in `srcBuffer`. + * + * The function requires a valid dctx state. + * It will read up to *srcSizePtr bytes from srcBuffer, + * and decompress data into dstBuffer, of capacity *dstSizePtr. + * + * The nb of bytes consumed from srcBuffer will be written into *srcSizePtr (necessarily <= original value). + * The nb of bytes decompressed into dstBuffer will be written into *dstSizePtr (necessarily <= original value). + * + * The function does not necessarily read all input bytes, so always check value in *srcSizePtr. + * Unconsumed source data must be presented again in subsequent invocations. + * + * `dstBuffer` can freely change between each consecutive function invocation. + * `dstBuffer` content will be overwritten. + * + * @return : an hint of how many `srcSize` bytes LZ4F_decompress() expects for next call. + * Schematically, it's the size of the current (or remaining) compressed block + header of next block. + * Respecting the hint provides some small speed benefit, because it skips intermediate buffers. + * This is just a hint though, it's always possible to provide any srcSize. + * + * When a frame is fully decoded, @return will be 0 (no more data expected). + * When provided with more bytes than necessary to decode a frame, + * LZ4F_decompress() will stop reading exactly at end of current frame, and @return 0. + * + * If decompression failed, @return is an error code, which can be tested using LZ4F_isError(). + * After a decompression error, the `dctx` context is not resumable. + * Use LZ4F_resetDecompressionContext() to return to clean state. + * + * After a frame is fully decoded, dctx can be used again to decompress another frame. + */ +LZ4FLIB_API size_t +LZ4F_decompress(LZ4F_dctx* dctx, + void* dstBuffer, size_t* dstSizePtr, + const void* srcBuffer, size_t* srcSizePtr, + const LZ4F_decompressOptions_t* dOptPtr); + + +/*! LZ4F_resetDecompressionContext() : added in v1.8.0 + * In case of an error, the context is left in "undefined" state. + * In which case, it's necessary to reset it, before re-using it. + * This method can also be used to abruptly stop any unfinished decompression, + * and start a new one using same context resources. */ +LZ4FLIB_API void LZ4F_resetDecompressionContext(LZ4F_dctx* dctx); /* always successful */ + + + +#if defined (__cplusplus) +} +#endif + +#endif /* LZ4F_H_09782039843 */ + +#if defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843) +#define LZ4F_H_STATIC_09782039843 + +#if defined (__cplusplus) +extern "C" { +#endif + +/* These declarations are not stable and may change in the future. + * They are therefore only safe to depend on + * when the caller is statically linked against the library. + * To access their declarations, define LZ4F_STATIC_LINKING_ONLY. + * + * By default, these symbols aren't published into shared/dynamic libraries. + * You can override this behavior and force them to be published + * by defining LZ4F_PUBLISH_STATIC_FUNCTIONS. + * Use at your own risk. + */ +#ifdef LZ4F_PUBLISH_STATIC_FUNCTIONS +# define LZ4FLIB_STATIC_API LZ4FLIB_API +#else +# define LZ4FLIB_STATIC_API +#endif + + +/* --- Error List --- */ +#define LZ4F_LIST_ERRORS(ITEM) \ + ITEM(OK_NoError) \ + ITEM(ERROR_GENERIC) \ + ITEM(ERROR_maxBlockSize_invalid) \ + ITEM(ERROR_blockMode_invalid) \ + ITEM(ERROR_contentChecksumFlag_invalid) \ + ITEM(ERROR_compressionLevel_invalid) \ + ITEM(ERROR_headerVersion_wrong) \ + ITEM(ERROR_blockChecksum_invalid) \ + ITEM(ERROR_reservedFlag_set) \ + ITEM(ERROR_allocation_failed) \ + ITEM(ERROR_srcSize_tooLarge) \ + ITEM(ERROR_dstMaxSize_tooSmall) \ + ITEM(ERROR_frameHeader_incomplete) \ + ITEM(ERROR_frameType_unknown) \ + ITEM(ERROR_frameSize_wrong) \ + ITEM(ERROR_srcPtr_wrong) \ + ITEM(ERROR_decompressionFailed) \ + ITEM(ERROR_headerChecksum_invalid) \ + ITEM(ERROR_contentChecksum_invalid) \ + ITEM(ERROR_frameDecoding_alreadyStarted) \ + ITEM(ERROR_compressionState_uninitialized) \ + ITEM(ERROR_parameter_null) \ + ITEM(ERROR_maxCode) + +#define LZ4F_GENERATE_ENUM(ENUM) LZ4F_##ENUM, + +/* enum list is exposed, to handle specific errors */ +typedef enum { LZ4F_LIST_ERRORS(LZ4F_GENERATE_ENUM) + _LZ4F_dummy_error_enum_for_c89_never_used } LZ4F_errorCodes; + +LZ4FLIB_STATIC_API LZ4F_errorCodes LZ4F_getErrorCode(size_t functionResult); + + +/*! LZ4F_getBlockSize() : + * Return, in scalar format (size_t), + * the maximum block size associated with blockSizeID. +**/ +LZ4FLIB_STATIC_API size_t LZ4F_getBlockSize(LZ4F_blockSizeID_t blockSizeID); + +/*! LZ4F_uncompressedUpdate() : + * LZ4F_uncompressedUpdate() can be called repetitively to add as much data uncompressed data as necessary. + * Important rule: dstCapacity MUST be large enough to store the entire source buffer as + * no compression is done for this operation + * If this condition is not respected, LZ4F_uncompressedUpdate() will fail (result is an errorCode). + * After an error, the state is left in a UB state, and must be re-initialized or freed. + * If previously a compressed block was written, buffered data is flushed + * before appending uncompressed data is continued. + * This is only supported when LZ4F_blockIndependent is used + * `cOptPtr` is optional : NULL can be provided, in which case all options are set to default. + * @return : number of bytes written into `dstBuffer` (it can be zero, meaning input data was just buffered). + * or an error code if it fails (which can be tested using LZ4F_isError()) + */ +LZ4FLIB_STATIC_API size_t +LZ4F_uncompressedUpdate(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const void* srcBuffer, size_t srcSize, + const LZ4F_compressOptions_t* cOptPtr); + +/********************************** + * Bulk processing dictionary API + *********************************/ + +/* A Dictionary is useful for the compression of small messages (KB range). + * It dramatically improves compression efficiency. + * + * LZ4 can ingest any input as dictionary, though only the last 64 KB are useful. + * Best results are generally achieved by using Zstandard's Dictionary Builder + * to generate a high-quality dictionary from a set of samples. + * + * Loading a dictionary has a cost, since it involves construction of tables. + * The Bulk processing dictionary API makes it possible to share this cost + * over an arbitrary number of compression jobs, even concurrently, + * markedly improving compression latency for these cases. + * + * The same dictionary will have to be used on the decompression side + * for decoding to be successful. + * To help identify the correct dictionary at decoding stage, + * the frame header allows optional embedding of a dictID field. + */ +typedef struct LZ4F_CDict_s LZ4F_CDict; + +/*! LZ4_createCDict() : + * When compressing multiple messages / blocks using the same dictionary, it's recommended to load it just once. + * LZ4_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay. + * LZ4_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only. + * `dictBuffer` can be released after LZ4_CDict creation, since its content is copied within CDict */ +LZ4FLIB_STATIC_API LZ4F_CDict* LZ4F_createCDict(const void* dictBuffer, size_t dictSize); +LZ4FLIB_STATIC_API void LZ4F_freeCDict(LZ4F_CDict* CDict); + + +/*! LZ4_compressFrame_usingCDict() : + * Compress an entire srcBuffer into a valid LZ4 frame using a digested Dictionary. + * cctx must point to a context created by LZ4F_createCompressionContext(). + * If cdict==NULL, compress without a dictionary. + * dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr). + * If this condition is not respected, function will fail (@return an errorCode). + * The LZ4F_preferences_t structure is optional : you may provide NULL as argument, + * but it's not recommended, as it's the only way to provide dictID in the frame header. + * @return : number of bytes written into dstBuffer. + * or an error code if it fails (can be tested using LZ4F_isError()) */ +LZ4FLIB_STATIC_API size_t +LZ4F_compressFrame_usingCDict(LZ4F_cctx* cctx, + void* dst, size_t dstCapacity, + const void* src, size_t srcSize, + const LZ4F_CDict* cdict, + const LZ4F_preferences_t* preferencesPtr); + + +/*! LZ4F_compressBegin_usingCDict() : + * Inits streaming dictionary compression, and writes the frame header into dstBuffer. + * dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes. + * `prefsPtr` is optional : you may provide NULL as argument, + * however, it's the only way to provide dictID in the frame header. + * @return : number of bytes written into dstBuffer for the header, + * or an error code (which can be tested using LZ4F_isError()) */ +LZ4FLIB_STATIC_API size_t +LZ4F_compressBegin_usingCDict(LZ4F_cctx* cctx, + void* dstBuffer, size_t dstCapacity, + const LZ4F_CDict* cdict, + const LZ4F_preferences_t* prefsPtr); + + +/*! LZ4F_decompress_usingDict() : + * Same as LZ4F_decompress(), using a predefined dictionary. + * Dictionary is used "in place", without any preprocessing. +** It must remain accessible throughout the entire frame decoding. */ +LZ4FLIB_STATIC_API size_t +LZ4F_decompress_usingDict(LZ4F_dctx* dctxPtr, + void* dstBuffer, size_t* dstSizePtr, + const void* srcBuffer, size_t* srcSizePtr, + const void* dict, size_t dictSize, + const LZ4F_decompressOptions_t* decompressOptionsPtr); + + +/*! Custom memory allocation : + * These prototypes make it possible to pass custom allocation/free functions. + * LZ4F_customMem is provided at state creation time, using LZ4F_create*_advanced() listed below. + * All allocation/free operations will be completed using these custom variants instead of regular ones. + */ +typedef void* (*LZ4F_AllocFunction) (void* opaqueState, size_t size); +typedef void* (*LZ4F_CallocFunction) (void* opaqueState, size_t size); +typedef void (*LZ4F_FreeFunction) (void* opaqueState, void* address); +typedef struct { + LZ4F_AllocFunction customAlloc; + LZ4F_CallocFunction customCalloc; /* optional; when not defined, uses customAlloc + memset */ + LZ4F_FreeFunction customFree; + void* opaqueState; +} LZ4F_CustomMem; +static +#ifdef __GNUC__ +__attribute__((__unused__)) +#endif +LZ4F_CustomMem const LZ4F_defaultCMem = { NULL, NULL, NULL, NULL }; /**< this constant defers to stdlib's functions */ + +LZ4FLIB_STATIC_API LZ4F_cctx* LZ4F_createCompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version); +LZ4FLIB_STATIC_API LZ4F_dctx* LZ4F_createDecompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version); +LZ4FLIB_STATIC_API LZ4F_CDict* LZ4F_createCDict_advanced(LZ4F_CustomMem customMem, const void* dictBuffer, size_t dictSize); + + +#if defined (__cplusplus) +} +#endif + +#endif /* defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843) */ diff --git a/cbits/lz4hc.c b/cbits/lz4hc.c --- a/cbits/lz4hc.c +++ b/cbits/lz4hc.c @@ -1,6 +1,6 @@ /* LZ4 HC - High Compression Mode of LZ4 - Copyright (C) 2011-2017, Yann Collet. + Copyright (C) 2011-2020, Yann Collet. BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) @@ -42,7 +42,7 @@ * Select how default compression function will allocate workplace memory, * in stack (0:fastest), or in heap (1:requires malloc()). * Since workplace is rather large, heap mode is recommended. - */ +**/ #ifndef LZ4HC_HEAPMODE # define LZ4HC_HEAPMODE 1 #endif @@ -53,7 +53,7 @@ #include "lz4hc.h" -/*=== Common LZ4 definitions ===*/ +/*=== Common definitions ===*/ #if defined(__GNUC__) # pragma GCC diagnostic ignored "-Wunused-function" #endif @@ -61,15 +61,16 @@ # pragma clang diagnostic ignored "-Wunused-function" #endif -/*=== Enums ===*/ -typedef enum { noDictCtx, usingDictCtxHc } dictCtx_directive; - - #define LZ4_COMMONDEFS_ONLY #ifndef LZ4_SRC_INCLUDED #include "lz4.c" /* LZ4_count, constants, mem */ #endif + +/*=== Enums ===*/ +typedef enum { noDictCtx, usingDictCtxHc } dictCtx_directive; + + /*=== Constants ===*/ #define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH) #define LZ4_OPT_NUM (1<<12) @@ -92,24 +93,26 @@ **************************************/ static void LZ4HC_clearTables (LZ4HC_CCtx_internal* hc4) { - MEM_INIT((void*)hc4->hashTable, 0, sizeof(hc4->hashTable)); + MEM_INIT(hc4->hashTable, 0, sizeof(hc4->hashTable)); MEM_INIT(hc4->chainTable, 0xFF, sizeof(hc4->chainTable)); } static void LZ4HC_init_internal (LZ4HC_CCtx_internal* hc4, const BYTE* start) { - uptrval startingOffset = (uptrval)(hc4->end - hc4->base); - if (startingOffset > 1 GB) { + size_t const bufferSize = (size_t)(hc4->end - hc4->prefixStart); + size_t newStartingOffset = bufferSize + hc4->dictLimit; + assert(newStartingOffset >= bufferSize); /* check overflow */ + if (newStartingOffset > 1 GB) { LZ4HC_clearTables(hc4); - startingOffset = 0; + newStartingOffset = 0; } - startingOffset += 64 KB; - hc4->nextToUpdate = (U32) startingOffset; - hc4->base = start - startingOffset; + newStartingOffset += 64 KB; + hc4->nextToUpdate = (U32)newStartingOffset; + hc4->prefixStart = start; hc4->end = start; - hc4->dictBase = start - startingOffset; - hc4->dictLimit = (U32) startingOffset; - hc4->lowLimit = (U32) startingOffset; + hc4->dictStart = start; + hc4->dictLimit = (U32)newStartingOffset; + hc4->lowLimit = (U32)newStartingOffset; } @@ -118,12 +121,15 @@ { U16* const chainTable = hc4->chainTable; U32* const hashTable = hc4->hashTable; - const BYTE* const base = hc4->base; - U32 const target = (U32)(ip - base); + const BYTE* const prefixPtr = hc4->prefixStart; + U32 const prefixIdx = hc4->dictLimit; + U32 const target = (U32)(ip - prefixPtr) + prefixIdx; U32 idx = hc4->nextToUpdate; + assert(ip >= prefixPtr); + assert(target >= prefixIdx); while (idx < target) { - U32 const h = LZ4HC_hashPtr(base+idx); + U32 const h = LZ4HC_hashPtr(prefixPtr+idx-prefixIdx); size_t delta = idx - hashTable[h]; if (delta>LZ4_DISTANCE_MAX) delta = LZ4_DISTANCE_MAX; DELTANEXTU16(chainTable, idx) = (U16)delta; @@ -161,8 +167,7 @@ static U32 LZ4HC_rotatePattern(size_t const rotate, U32 const pattern) { size_t const bitsToRotate = (rotate & (sizeof(pattern) - 1)) << 3; - if (bitsToRotate == 0) - return pattern; + if (bitsToRotate == 0) return pattern; return LZ4HC_rotl32(pattern, (int)bitsToRotate); } @@ -172,7 +177,8 @@ LZ4HC_countPattern(const BYTE* ip, const BYTE* const iEnd, U32 const pattern32) { const BYTE* const iStart = ip; - reg_t const pattern = (sizeof(pattern)==8) ? (reg_t)pattern32 + (((reg_t)pattern32) << 32) : pattern32; + reg_t const pattern = (sizeof(pattern)==8) ? + (reg_t)pattern32 + (((reg_t)pattern32) << (sizeof(pattern)*4)) : pattern32; while (likely(ip < iEnd-(sizeof(pattern)-1))) { reg_t const diff = LZ4_read_ARCH(ip) ^ pattern; @@ -192,15 +198,14 @@ BYTE const byte = (BYTE)(pattern >> bitOffset); if (*ip != byte) break; ip ++; bitOffset -= 8; - } - } + } } return (unsigned)(ip - iStart); } /* LZ4HC_reverseCountPattern() : * pattern must be a sample of repetitive pattern of length 1, 2 or 4 (but not 3!) - * read using natural platform endianess */ + * read using natural platform endianness */ static unsigned LZ4HC_reverseCountPattern(const BYTE* ip, const BYTE* const iLow, U32 pattern) { @@ -210,7 +215,7 @@ if (LZ4_read32(ip-4) != pattern) break; ip -= 4; } - { const BYTE* bytePtr = (const BYTE*)(&pattern) + 3; /* works for any endianess */ + { const BYTE* bytePtr = (const BYTE*)(&pattern) + 3; /* works for any endianness */ while (likely(ip>iLow)) { if (ip[-1] != *bytePtr) break; ip--; bytePtr--; @@ -233,28 +238,28 @@ LZ4_FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch ( - LZ4HC_CCtx_internal* hc4, - const BYTE* const ip, - const BYTE* const iLowLimit, - const BYTE* const iHighLimit, - int longest, - const BYTE** matchpos, - const BYTE** startpos, - const int maxNbAttempts, - const int patternAnalysis, - const int chainSwap, - const dictCtx_directive dict, - const HCfavor_e favorDecSpeed) + LZ4HC_CCtx_internal* const hc4, + const BYTE* const ip, + const BYTE* const iLowLimit, const BYTE* const iHighLimit, + int longest, + const BYTE** matchpos, + const BYTE** startpos, + const int maxNbAttempts, + const int patternAnalysis, const int chainSwap, + const dictCtx_directive dict, + const HCfavor_e favorDecSpeed) { U16* const chainTable = hc4->chainTable; U32* const HashTable = hc4->hashTable; const LZ4HC_CCtx_internal * const dictCtx = hc4->dictCtx; - const BYTE* const base = hc4->base; - const U32 dictLimit = hc4->dictLimit; - const BYTE* const lowPrefixPtr = base + dictLimit; - const U32 ipIndex = (U32)(ip - base); - const U32 lowestMatchIndex = (hc4->lowLimit + (LZ4_DISTANCE_MAX + 1) > ipIndex) ? hc4->lowLimit : ipIndex - LZ4_DISTANCE_MAX; - const BYTE* const dictBase = hc4->dictBase; + const BYTE* const prefixPtr = hc4->prefixStart; + const U32 prefixIdx = hc4->dictLimit; + const U32 ipIndex = (U32)(ip - prefixPtr) + prefixIdx; + const int withinStartDistance = (hc4->lowLimit + (LZ4_DISTANCE_MAX + 1) > ipIndex); + const U32 lowestMatchIndex = (withinStartDistance) ? hc4->lowLimit : ipIndex - LZ4_DISTANCE_MAX; + const BYTE* const dictStart = hc4->dictStart; + const U32 dictIdx = hc4->lowLimit; + const BYTE* const dictEnd = dictStart + prefixIdx - dictIdx; int const lookBackLength = (int)(ip-iLowLimit); int nbAttempts = maxNbAttempts; U32 matchChainPos = 0; @@ -270,20 +275,19 @@ DEBUGLOG(7, "First match at index %u / %u (lowestMatchIndex)", matchIndex, lowestMatchIndex); - while ((matchIndex>=lowestMatchIndex) && (nbAttempts)) { + while ((matchIndex>=lowestMatchIndex) && (nbAttempts>0)) { int matchLength=0; nbAttempts--; assert(matchIndex < ipIndex); if (favorDecSpeed && (ipIndex - matchIndex < 8)) { /* do nothing */ - } else if (matchIndex >= dictLimit) { /* within current Prefix */ - const BYTE* const matchPtr = base + matchIndex; - assert(matchPtr >= lowPrefixPtr); + } else if (matchIndex >= prefixIdx) { /* within current Prefix */ + const BYTE* const matchPtr = prefixPtr + matchIndex - prefixIdx; assert(matchPtr < ip); assert(longest >= 1); if (LZ4_read16(iLowLimit + longest - 1) == LZ4_read16(matchPtr - lookBackLength + longest - 1)) { if (LZ4_read32(matchPtr) == pattern) { - int const back = lookBackLength ? LZ4HC_countBack(ip, matchPtr, iLowLimit, lowPrefixPtr) : 0; + int const back = lookBackLength ? LZ4HC_countBack(ip, matchPtr, iLowLimit, prefixPtr) : 0; matchLength = MINMATCH + (int)LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, iHighLimit); matchLength -= back; if (matchLength > longest) { @@ -292,24 +296,25 @@ *startpos = ip + back; } } } } else { /* lowestMatchIndex <= matchIndex < dictLimit */ - const BYTE* const matchPtr = dictBase + matchIndex; - if (LZ4_read32(matchPtr) == pattern) { - const BYTE* const dictStart = dictBase + hc4->lowLimit; + const BYTE* const matchPtr = dictStart + (matchIndex - dictIdx); + assert(matchIndex >= dictIdx); + if ( likely(matchIndex <= prefixIdx - 4) + && (LZ4_read32(matchPtr) == pattern) ) { int back = 0; - const BYTE* vLimit = ip + (dictLimit - matchIndex); + const BYTE* vLimit = ip + (prefixIdx - matchIndex); if (vLimit > iHighLimit) vLimit = iHighLimit; matchLength = (int)LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, vLimit) + MINMATCH; if ((ip+matchLength == vLimit) && (vLimit < iHighLimit)) - matchLength += LZ4_count(ip+matchLength, lowPrefixPtr, iHighLimit); + matchLength += LZ4_count(ip+matchLength, prefixPtr, iHighLimit); back = lookBackLength ? LZ4HC_countBack(ip, matchPtr, iLowLimit, dictStart) : 0; matchLength -= back; if (matchLength > longest) { longest = matchLength; - *matchpos = base + matchIndex + back; /* virtual pos, relative to ip, to retrieve offset */ + *matchpos = prefixPtr - prefixIdx + matchIndex + back; /* virtual pos, relative to ip, to retrieve offset */ *startpos = ip + back; } } } - if (chainSwap && matchLength==longest) { /* better match => select a better chain */ + if (chainSwap && matchLength==longest) { /* better match => select a better chain */ assert(lookBackLength==0); /* search forward only */ if (matchIndex + (U32)longest <= ipIndex) { int const kTrigger = 4; @@ -325,8 +330,7 @@ distanceToNextMatch = candidateDist; matchChainPos = (U32)pos; accel = 1 << kTrigger; - } - } + } } if (distanceToNextMatch > 1) { if (distanceToNextMatch > matchIndex) break; /* avoid overflow */ matchIndex -= distanceToNextMatch; @@ -346,23 +350,24 @@ repeat = rep_not; } } if ( (repeat == rep_confirmed) && (matchCandidateIdx >= lowestMatchIndex) - && LZ4HC_protectDictEnd(dictLimit, matchCandidateIdx) ) { - const int extDict = matchCandidateIdx < dictLimit; - const BYTE* const matchPtr = (extDict ? dictBase : base) + matchCandidateIdx; + && LZ4HC_protectDictEnd(prefixIdx, matchCandidateIdx) ) { + const int extDict = matchCandidateIdx < prefixIdx; + const BYTE* const matchPtr = (extDict ? dictStart - dictIdx : prefixPtr - prefixIdx) + matchCandidateIdx; if (LZ4_read32(matchPtr) == pattern) { /* good candidate */ - const BYTE* const dictStart = dictBase + hc4->lowLimit; - const BYTE* const iLimit = extDict ? dictBase + dictLimit : iHighLimit; + const BYTE* const iLimit = extDict ? dictEnd : iHighLimit; size_t forwardPatternLength = LZ4HC_countPattern(matchPtr+sizeof(pattern), iLimit, pattern) + sizeof(pattern); if (extDict && matchPtr + forwardPatternLength == iLimit) { U32 const rotatedPattern = LZ4HC_rotatePattern(forwardPatternLength, pattern); - forwardPatternLength += LZ4HC_countPattern(lowPrefixPtr, iHighLimit, rotatedPattern); + forwardPatternLength += LZ4HC_countPattern(prefixPtr, iHighLimit, rotatedPattern); } - { const BYTE* const lowestMatchPtr = extDict ? dictStart : lowPrefixPtr; + { const BYTE* const lowestMatchPtr = extDict ? dictStart : prefixPtr; size_t backLength = LZ4HC_reverseCountPattern(matchPtr, lowestMatchPtr, pattern); size_t currentSegmentLength; - if (!extDict && matchPtr - backLength == lowPrefixPtr && hc4->lowLimit < dictLimit) { + if (!extDict + && matchPtr - backLength == prefixPtr + && dictIdx < prefixIdx) { U32 const rotatedPattern = LZ4HC_rotatePattern((U32)(-(int)backLength), pattern); - backLength += LZ4HC_reverseCountPattern(dictBase + dictLimit, dictStart, rotatedPattern); + backLength += LZ4HC_reverseCountPattern(dictEnd, dictStart, rotatedPattern); } /* Limit backLength not go further than lowestMatchIndex */ backLength = matchCandidateIdx - MAX(matchCandidateIdx - (U32)backLength, lowestMatchIndex); @@ -372,28 +377,28 @@ if ( (currentSegmentLength >= srcPatternLength) /* current pattern segment large enough to contain full srcPatternLength */ && (forwardPatternLength <= srcPatternLength) ) { /* haven't reached this position yet */ U32 const newMatchIndex = matchCandidateIdx + (U32)forwardPatternLength - (U32)srcPatternLength; /* best position, full pattern, might be followed by more match */ - if (LZ4HC_protectDictEnd(dictLimit, newMatchIndex)) + if (LZ4HC_protectDictEnd(prefixIdx, newMatchIndex)) matchIndex = newMatchIndex; else { /* Can only happen if started in the prefix */ - assert(newMatchIndex >= dictLimit - 3 && newMatchIndex < dictLimit && !extDict); - matchIndex = dictLimit; + assert(newMatchIndex >= prefixIdx - 3 && newMatchIndex < prefixIdx && !extDict); + matchIndex = prefixIdx; } } else { U32 const newMatchIndex = matchCandidateIdx - (U32)backLength; /* farthest position in current segment, will find a match of length currentSegmentLength + maybe some back */ - if (!LZ4HC_protectDictEnd(dictLimit, newMatchIndex)) { - assert(newMatchIndex >= dictLimit - 3 && newMatchIndex < dictLimit && !extDict); - matchIndex = dictLimit; + if (!LZ4HC_protectDictEnd(prefixIdx, newMatchIndex)) { + assert(newMatchIndex >= prefixIdx - 3 && newMatchIndex < prefixIdx && !extDict); + matchIndex = prefixIdx; } else { matchIndex = newMatchIndex; if (lookBackLength==0) { /* no back possible */ size_t const maxML = MIN(currentSegmentLength, srcPatternLength); if ((size_t)longest < maxML) { - assert(base + matchIndex != ip); - if ((size_t)(ip - base) - matchIndex > LZ4_DISTANCE_MAX) break; + assert(prefixPtr - prefixIdx + matchIndex != ip); + if ((size_t)(ip - prefixPtr) + prefixIdx - matchIndex > LZ4_DISTANCE_MAX) break; assert(maxML < 2 GB); longest = (int)maxML; - *matchpos = base + matchIndex; /* virtual pos, relative to ip, to retrieve offset */ + *matchpos = prefixPtr - prefixIdx + matchIndex; /* virtual pos, relative to ip, to retrieve offset */ *startpos = ip; } { U32 const distToNextPattern = DELTANEXTU16(chainTable, matchIndex); @@ -410,14 +415,14 @@ } /* while ((matchIndex>=lowestMatchIndex) && (nbAttempts)) */ if ( dict == usingDictCtxHc - && nbAttempts + && nbAttempts > 0 && ipIndex - lowestMatchIndex < LZ4_DISTANCE_MAX) { - size_t const dictEndOffset = (size_t)(dictCtx->end - dictCtx->base); + size_t const dictEndOffset = (size_t)(dictCtx->end - dictCtx->prefixStart) + dictCtx->dictLimit; U32 dictMatchIndex = dictCtx->hashTable[LZ4HC_hashPtr(ip)]; assert(dictEndOffset <= 1 GB); matchIndex = dictMatchIndex + lowestMatchIndex - (U32)dictEndOffset; while (ipIndex - matchIndex <= LZ4_DISTANCE_MAX && nbAttempts--) { - const BYTE* const matchPtr = dictCtx->base + dictMatchIndex; + const BYTE* const matchPtr = dictCtx->prefixStart - dictCtx->dictLimit + dictMatchIndex; if (LZ4_read32(matchPtr) == pattern) { int mlt; @@ -425,11 +430,11 @@ const BYTE* vLimit = ip + (dictEndOffset - dictMatchIndex); if (vLimit > iHighLimit) vLimit = iHighLimit; mlt = (int)LZ4_count(ip+MINMATCH, matchPtr+MINMATCH, vLimit) + MINMATCH; - back = lookBackLength ? LZ4HC_countBack(ip, matchPtr, iLowLimit, dictCtx->base + dictCtx->dictLimit) : 0; + back = lookBackLength ? LZ4HC_countBack(ip, matchPtr, iLowLimit, dictCtx->prefixStart) : 0; mlt -= back; if (mlt > longest) { longest = mlt; - *matchpos = base + matchIndex + back; + *matchpos = prefixPtr - prefixIdx + matchIndex + back; *startpos = ip + back; } } @@ -441,13 +446,13 @@ return longest; } -LZ4_FORCE_INLINE -int LZ4HC_InsertAndFindBestMatch(LZ4HC_CCtx_internal* const hc4, /* Index table will be updated */ - const BYTE* const ip, const BYTE* const iLimit, - const BYTE** matchpos, - const int maxNbAttempts, - const int patternAnalysis, - const dictCtx_directive dict) +LZ4_FORCE_INLINE int +LZ4HC_InsertAndFindBestMatch(LZ4HC_CCtx_internal* const hc4, /* Index table will be updated */ + const BYTE* const ip, const BYTE* const iLimit, + const BYTE** matchpos, + const int maxNbAttempts, + const int patternAnalysis, + const dictCtx_directive dict) { const BYTE* uselessPtr = ip; /* note : LZ4HC_InsertAndGetWiderMatch() is able to modify the starting position of a match (*startpos), @@ -460,74 +465,90 @@ * @return : 0 if ok, * 1 if buffer issue detected */ LZ4_FORCE_INLINE int LZ4HC_encodeSequence ( - const BYTE** ip, - BYTE** op, - const BYTE** anchor, + const BYTE** _ip, + BYTE** _op, + const BYTE** _anchor, int matchLength, const BYTE* const match, limitedOutput_directive limit, BYTE* oend) { +#define ip (*_ip) +#define op (*_op) +#define anchor (*_anchor) + size_t length; - BYTE* const token = (*op)++; + BYTE* const token = op++; #if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 6) static const BYTE* start = NULL; static U32 totalCost = 0; - U32 const pos = (start==NULL) ? 0 : (U32)(*anchor - start); - U32 const ll = (U32)(*ip - *anchor); + U32 const pos = (start==NULL) ? 0 : (U32)(anchor - start); + U32 const ll = (U32)(ip - anchor); U32 const llAdd = (ll>=15) ? ((ll-15) / 255) + 1 : 0; U32 const mlAdd = (matchLength>=19) ? ((matchLength-19) / 255) + 1 : 0; U32 const cost = 1 + llAdd + ll + 2 + mlAdd; - if (start==NULL) start = *anchor; /* only works for single segment */ + if (start==NULL) start = anchor; /* only works for single segment */ /* g_debuglog_enable = (pos >= 2228) & (pos <= 2262); */ - DEBUGLOG(6, "pos:%7u -- literals:%3u, match:%4i, offset:%5u, cost:%3u + %u", + DEBUGLOG(6, "pos:%7u -- literals:%4u, match:%4i, offset:%5u, cost:%4u + %5u", pos, - (U32)(*ip - *anchor), matchLength, (U32)(*ip-match), + (U32)(ip - anchor), matchLength, (U32)(ip-match), cost, totalCost); totalCost += cost; #endif /* Encode Literal length */ - length = (size_t)(*ip - *anchor); - if ((limit) && ((*op + (length / 255) + length + (2 + 1 + LASTLITERALS)) > oend)) return 1; /* Check output limit */ + length = (size_t)(ip - anchor); + LZ4_STATIC_ASSERT(notLimited == 0); + /* Check output limit */ + if (limit && ((op + (length / 255) + length + (2 + 1 + LASTLITERALS)) > oend)) { + DEBUGLOG(6, "Not enough room to write %i literals (%i bytes remaining)", + (int)length, (int)(oend - op)); + return 1; + } if (length >= RUN_MASK) { size_t len = length - RUN_MASK; *token = (RUN_MASK << ML_BITS); - for(; len >= 255 ; len -= 255) *(*op)++ = 255; - *(*op)++ = (BYTE)len; + for(; len >= 255 ; len -= 255) *op++ = 255; + *op++ = (BYTE)len; } else { *token = (BYTE)(length << ML_BITS); } /* Copy Literals */ - LZ4_wildCopy8(*op, *anchor, (*op) + length); - *op += length; + LZ4_wildCopy8(op, anchor, op + length); + op += length; /* Encode Offset */ - assert( (*ip - match) <= LZ4_DISTANCE_MAX ); /* note : consider providing offset as a value, rather than as a pointer difference */ - LZ4_writeLE16(*op, (U16)(*ip-match)); *op += 2; + assert( (ip - match) <= LZ4_DISTANCE_MAX ); /* note : consider providing offset as a value, rather than as a pointer difference */ + LZ4_writeLE16(op, (U16)(ip - match)); op += 2; /* Encode MatchLength */ assert(matchLength >= MINMATCH); length = (size_t)matchLength - MINMATCH; - if ((limit) && (*op + (length / 255) + (1 + LASTLITERALS) > oend)) return 1; /* Check output limit */ + if (limit && (op + (length / 255) + (1 + LASTLITERALS) > oend)) { + DEBUGLOG(6, "Not enough room to write match length"); + return 1; /* Check output limit */ + } if (length >= ML_MASK) { *token += ML_MASK; length -= ML_MASK; - for(; length >= 510 ; length -= 510) { *(*op)++ = 255; *(*op)++ = 255; } - if (length >= 255) { length -= 255; *(*op)++ = 255; } - *(*op)++ = (BYTE)length; + for(; length >= 510 ; length -= 510) { *op++ = 255; *op++ = 255; } + if (length >= 255) { length -= 255; *op++ = 255; } + *op++ = (BYTE)length; } else { *token += (BYTE)(length); } /* Prepare next loop */ - *ip += matchLength; - *anchor = *ip; + ip += matchLength; + anchor = ip; return 0; } +#undef ip +#undef op +#undef anchor LZ4_FORCE_INLINE int LZ4HC_compress_hashChain ( LZ4HC_CCtx_internal* const ctx, @@ -535,7 +556,7 @@ char* const dest, int* srcSizePtr, int const maxOutputSize, - unsigned maxNbAttempts, + int maxNbAttempts, const limitedOutput_directive limit, const dictCtx_directive dict ) @@ -565,7 +586,7 @@ /* init */ *srcSizePtr = 0; if (limit == fillOutput) oend -= LASTLITERALS; /* Hack for support LZ4 format restriction */ - if (inputSize < LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ + if (inputSize < LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ /* Main Loop */ while (ip <= mflimit) { @@ -637,7 +658,11 @@ if (LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml, ref, limit, oend)) goto _dest_overflow; ip = start2; optr = op; - if (LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml2, ref2, limit, oend)) goto _dest_overflow; + if (LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml2, ref2, limit, oend)) { + ml = ml2; + ref = ref2; + goto _dest_overflow; + } continue; } @@ -709,17 +734,18 @@ _last_literals: /* Encode Last Literals */ { size_t lastRunSize = (size_t)(iend - anchor); /* literals */ - size_t litLength = (lastRunSize + 255 - RUN_MASK) / 255; - size_t const totalSize = 1 + litLength + lastRunSize; + size_t llAdd = (lastRunSize + 255 - RUN_MASK) / 255; + size_t const totalSize = 1 + llAdd + lastRunSize; if (limit == fillOutput) oend += LASTLITERALS; /* restore correct value */ if (limit && (op + totalSize > oend)) { - if (limit == limitedOutput) return 0; /* Check output limit */ + if (limit == limitedOutput) return 0; /* adapt lastRunSize to fill 'dest' */ - lastRunSize = (size_t)(oend - op) - 1; - litLength = (lastRunSize + 255 - RUN_MASK) / 255; - lastRunSize -= litLength; + lastRunSize = (size_t)(oend - op) - 1 /*token*/; + llAdd = (lastRunSize + 256 - RUN_MASK) / 256; + lastRunSize -= llAdd; } - ip = anchor + lastRunSize; + DEBUGLOG(6, "Final literal run : %i literals", (int)lastRunSize); + ip = anchor + lastRunSize; /* can be != iend if limit==fillOutput */ if (lastRunSize >= RUN_MASK) { size_t accumulator = lastRunSize - RUN_MASK; @@ -729,7 +755,7 @@ } else { *op++ = (BYTE)(lastRunSize << ML_BITS); } - memcpy(op, anchor, lastRunSize); + LZ4_memcpy(op, anchor, lastRunSize); op += lastRunSize; } @@ -739,9 +765,25 @@ _dest_overflow: if (limit == fillOutput) { + /* Assumption : ip, anchor, ml and ref must be set correctly */ + size_t const ll = (size_t)(ip - anchor); + size_t const ll_addbytes = (ll + 240) / 255; + size_t const ll_totalCost = 1 + ll_addbytes + ll; + BYTE* const maxLitPos = oend - 3; /* 2 for offset, 1 for token */ + DEBUGLOG(6, "Last sequence overflowing"); op = optr; /* restore correct out pointer */ + if (op + ll_totalCost <= maxLitPos) { + /* ll validated; now adjust match length */ + size_t const bytesLeftForMl = (size_t)(maxLitPos - (op+ll_totalCost)); + size_t const maxMlSize = MINMATCH + (ML_MASK-1) + (bytesLeftForMl * 255); + assert(maxMlSize < INT_MAX); assert(ml >= 0); + if ((size_t)ml > maxMlSize) ml = (int)maxMlSize; + if ((oend + LASTLITERALS) - (op + ll_totalCost + 2) - 1 + ml >= MFLIMIT) { + LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml, ref, notLimited, oend); + } } goto _last_literals; } + /* compression failed */ return 0; } @@ -752,7 +794,7 @@ int const nbSearches, size_t sufficient_len, const limitedOutput_directive limit, int const fullUpdate, const dictCtx_directive dict, - HCfavor_e favorDecSpeed); + const HCfavor_e favorDecSpeed); LZ4_FORCE_INLINE int LZ4HC_compress_generic_internal ( @@ -769,7 +811,7 @@ typedef enum { lz4hc, lz4opt } lz4hc_strat_e; typedef struct { lz4hc_strat_e strat; - U32 nbSearches; + int nbSearches; U32 targetLength; } cParams_t; static const cParams_t clTable[LZ4HC_CLEVEL_MAX+1] = { @@ -788,7 +830,8 @@ { lz4opt,16384,LZ4_OPT_NUM }, /* 12==LZ4HC_CLEVEL_MAX */ }; - DEBUGLOG(4, "LZ4HC_compress_generic(ctx=%p, src=%p, srcSize=%d)", ctx, src, *srcSizePtr); + DEBUGLOG(4, "LZ4HC_compress_generic(ctx=%p, src=%p, srcSize=%d, limit=%d)", + ctx, src, *srcSizePtr, limit); if (limit == fillOutput && dstCapacity < 1) return 0; /* Impossible to store anything */ if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size (too large or negative) */ @@ -808,7 +851,7 @@ assert(cParam.strat == lz4opt); result = LZ4HC_compress_optimal(ctx, src, dst, srcSizePtr, dstCapacity, - (int)cParam.nbSearches, cParam.targetLength, limit, + cParam.nbSearches, cParam.targetLength, limit, cLevel == LZ4HC_CLEVEL_MAX, /* ultra mode */ dict, favor); } @@ -845,13 +888,13 @@ limitedOutput_directive limit ) { - const size_t position = (size_t)(ctx->end - ctx->base) - ctx->lowLimit; + const size_t position = (size_t)(ctx->end - ctx->prefixStart) + (ctx->dictLimit - ctx->lowLimit); assert(ctx->dictCtx != NULL); if (position >= 64 KB) { ctx->dictCtx = NULL; return LZ4HC_compress_generic_noDictCtx(ctx, src, dst, srcSizePtr, dstCapacity, cLevel, limit); } else if (position == 0 && *srcSizePtr > 4 KB) { - memcpy(ctx, ctx->dictCtx, sizeof(LZ4HC_CCtx_internal)); + LZ4_memcpy(ctx, ctx->dictCtx, sizeof(LZ4HC_CCtx_internal)); LZ4HC_setExternalDict(ctx, (const BYTE *)src); ctx->compressionLevel = (short)cLevel; return LZ4HC_compress_generic_noDictCtx(ctx, src, dst, srcSizePtr, dstCapacity, cLevel, limit); @@ -881,27 +924,22 @@ int LZ4_sizeofStateHC(void) { return (int)sizeof(LZ4_streamHC_t); } -#ifndef _MSC_VER /* for some reason, Visual fails the aligment test on 32-bit x86 : - * it reports an aligment of 8-bytes, - * while actually aligning LZ4_streamHC_t on 4 bytes. */ static size_t LZ4_streamHC_t_alignment(void) { - struct { char c; LZ4_streamHC_t t; } t_a; - return sizeof(t_a) - sizeof(t_a.t); -} +#if LZ4_ALIGN_TEST + typedef struct { char c; LZ4_streamHC_t t; } t_a; + return sizeof(t_a) - sizeof(LZ4_streamHC_t); +#else + return 1; /* effectively disabled */ #endif +} /* state is presumed correctly initialized, * in which case its size and alignment have already been validate */ int LZ4_compress_HC_extStateHC_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel) { LZ4HC_CCtx_internal* const ctx = &((LZ4_streamHC_t*)state)->internal_donotuse; -#ifndef _MSC_VER /* for some reason, Visual fails the aligment test on 32-bit x86 : - * it reports an aligment of 8-bytes, - * while actually aligning LZ4_streamHC_t on 4 bytes. */ - assert(((size_t)state & (LZ4_streamHC_t_alignment() - 1)) == 0); /* check alignment */ -#endif - if (((size_t)(state)&(sizeof(void*)-1)) != 0) return 0; /* Error : state is not aligned for pointers (32 or 64 bits) */ + if (!LZ4_isAligned(state, LZ4_streamHC_t_alignment())) return 0; LZ4_resetStreamHC_fast((LZ4_streamHC_t*)state, compressionLevel); LZ4HC_init_internal (ctx, (const BYTE*)src); if (dstCapacity < LZ4_compressBound(srcSize)) @@ -919,13 +957,15 @@ int LZ4_compress_HC(const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel) { + int cSize; #if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 LZ4_streamHC_t* const statePtr = (LZ4_streamHC_t*)ALLOC(sizeof(LZ4_streamHC_t)); + if (statePtr==NULL) return 0; #else LZ4_streamHC_t state; LZ4_streamHC_t* const statePtr = &state; #endif - int const cSize = LZ4_compress_HC_extStateHC(statePtr, src, dst, srcSize, dstCapacity, compressionLevel); + cSize = LZ4_compress_HC_extStateHC(statePtr, src, dst, srcSize, dstCapacity, compressionLevel); #if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 FREEMEM(statePtr); #endif @@ -948,12 +988,14 @@ * Streaming Functions **************************************/ /* allocation */ +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) LZ4_streamHC_t* LZ4_createStreamHC(void) { - LZ4_streamHC_t* const LZ4_streamHCPtr = (LZ4_streamHC_t*)ALLOC(sizeof(LZ4_streamHC_t)); - if (LZ4_streamHCPtr==NULL) return NULL; - LZ4_initStreamHC(LZ4_streamHCPtr, sizeof(*LZ4_streamHCPtr)); /* full initialization, malloc'ed buffer can be full of garbage */ - return LZ4_streamHCPtr; + LZ4_streamHC_t* const state = + (LZ4_streamHC_t*)ALLOC_AND_ZERO(sizeof(LZ4_streamHC_t)); + if (state == NULL) return NULL; + LZ4_setCompressionLevel(state, LZ4HC_CLEVEL_DEFAULT); + return state; } int LZ4_freeStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr) @@ -963,27 +1005,20 @@ FREEMEM(LZ4_streamHCPtr); return 0; } +#endif LZ4_streamHC_t* LZ4_initStreamHC (void* buffer, size_t size) { LZ4_streamHC_t* const LZ4_streamHCPtr = (LZ4_streamHC_t*)buffer; + DEBUGLOG(4, "LZ4_initStreamHC(%p, %u)", buffer, (unsigned)size); + /* check conditions */ if (buffer == NULL) return NULL; if (size < sizeof(LZ4_streamHC_t)) return NULL; -#ifndef _MSC_VER /* for some reason, Visual fails the aligment test on 32-bit x86 : - * it reports an aligment of 8-bytes, - * while actually aligning LZ4_streamHC_t on 4 bytes. */ - if (((size_t)buffer) & (LZ4_streamHC_t_alignment() - 1)) return NULL; /* alignment check */ -#endif - /* if compilation fails here, LZ4_STREAMHCSIZE must be increased */ - LZ4_STATIC_ASSERT(sizeof(LZ4HC_CCtx_internal) <= LZ4_STREAMHCSIZE); - DEBUGLOG(4, "LZ4_initStreamHC(%p, %u)", LZ4_streamHCPtr, (unsigned)size); - /* end-base will trigger a clearTable on starting compression */ - LZ4_streamHCPtr->internal_donotuse.end = (const BYTE *)(ptrdiff_t)-1; - LZ4_streamHCPtr->internal_donotuse.base = NULL; - LZ4_streamHCPtr->internal_donotuse.dictCtx = NULL; - LZ4_streamHCPtr->internal_donotuse.favorDecSpeed = 0; - LZ4_streamHCPtr->internal_donotuse.dirty = 0; + if (!LZ4_isAligned(buffer, LZ4_streamHC_t_alignment())) return NULL; + /* init */ + { LZ4HC_CCtx_internal* const hcstate = &(LZ4_streamHCPtr->internal_donotuse); + MEM_INIT(hcstate, 0, sizeof(*hcstate)); } LZ4_setCompressionLevel(LZ4_streamHCPtr, LZ4HC_CLEVEL_DEFAULT); return LZ4_streamHCPtr; } @@ -1001,9 +1036,13 @@ if (LZ4_streamHCPtr->internal_donotuse.dirty) { LZ4_initStreamHC(LZ4_streamHCPtr, sizeof(*LZ4_streamHCPtr)); } else { - /* preserve end - base : can trigger clearTable's threshold */ - LZ4_streamHCPtr->internal_donotuse.end -= (uptrval)LZ4_streamHCPtr->internal_donotuse.base; - LZ4_streamHCPtr->internal_donotuse.base = NULL; + /* preserve end - prefixStart : can trigger clearTable's threshold */ + if (LZ4_streamHCPtr->internal_donotuse.end != NULL) { + LZ4_streamHCPtr->internal_donotuse.end -= (uptrval)LZ4_streamHCPtr->internal_donotuse.prefixStart; + } else { + assert(LZ4_streamHCPtr->internal_donotuse.prefixStart == NULL); + } + LZ4_streamHCPtr->internal_donotuse.prefixStart = NULL; LZ4_streamHCPtr->internal_donotuse.dictCtx = NULL; } LZ4_setCompressionLevel(LZ4_streamHCPtr, compressionLevel); @@ -1054,14 +1093,14 @@ static void LZ4HC_setExternalDict(LZ4HC_CCtx_internal* ctxPtr, const BYTE* newBlock) { DEBUGLOG(4, "LZ4HC_setExternalDict(%p, %p)", ctxPtr, newBlock); - if (ctxPtr->end >= ctxPtr->base + ctxPtr->dictLimit + 4) + if (ctxPtr->end >= ctxPtr->prefixStart + 4) LZ4HC_Insert (ctxPtr, ctxPtr->end-3); /* Referencing remaining dictionary content */ /* Only one memory segment for extDict, so any previous extDict is lost at this stage */ ctxPtr->lowLimit = ctxPtr->dictLimit; - ctxPtr->dictLimit = (U32)(ctxPtr->end - ctxPtr->base); - ctxPtr->dictBase = ctxPtr->base; - ctxPtr->base = newBlock - ctxPtr->dictLimit; + ctxPtr->dictStart = ctxPtr->prefixStart; + ctxPtr->dictLimit += (U32)(ctxPtr->end - ctxPtr->prefixStart); + ctxPtr->prefixStart = newBlock; ctxPtr->end = newBlock; ctxPtr->nextToUpdate = ctxPtr->dictLimit; /* match referencing will resume from there */ @@ -1069,21 +1108,22 @@ ctxPtr->dictCtx = NULL; } -static int LZ4_compressHC_continue_generic (LZ4_streamHC_t* LZ4_streamHCPtr, - const char* src, char* dst, - int* srcSizePtr, int dstCapacity, - limitedOutput_directive limit) +static int +LZ4_compressHC_continue_generic (LZ4_streamHC_t* LZ4_streamHCPtr, + const char* src, char* dst, + int* srcSizePtr, int dstCapacity, + limitedOutput_directive limit) { LZ4HC_CCtx_internal* const ctxPtr = &LZ4_streamHCPtr->internal_donotuse; - DEBUGLOG(4, "LZ4_compressHC_continue_generic(ctx=%p, src=%p, srcSize=%d)", - LZ4_streamHCPtr, src, *srcSizePtr); + DEBUGLOG(5, "LZ4_compressHC_continue_generic(ctx=%p, src=%p, srcSize=%d, limit=%d)", + LZ4_streamHCPtr, src, *srcSizePtr, limit); assert(ctxPtr != NULL); /* auto-init if forgotten */ - if (ctxPtr->base == NULL) LZ4HC_init_internal (ctxPtr, (const BYTE*) src); + if (ctxPtr->prefixStart == NULL) LZ4HC_init_internal (ctxPtr, (const BYTE*) src); /* Check overflow */ - if ((size_t)(ctxPtr->end - ctxPtr->base) > 2 GB) { - size_t dictSize = (size_t)(ctxPtr->end - ctxPtr->base) - ctxPtr->dictLimit; + if ((size_t)(ctxPtr->end - ctxPtr->prefixStart) + ctxPtr->dictLimit > 2 GB) { + size_t dictSize = (size_t)(ctxPtr->end - ctxPtr->prefixStart); if (dictSize > 64 KB) dictSize = 64 KB; LZ4_loadDictHC(LZ4_streamHCPtr, (const char*)(ctxPtr->end) - dictSize, (int)dictSize); } @@ -1094,14 +1134,16 @@ /* Check overlapping input/dictionary space */ { const BYTE* sourceEnd = (const BYTE*) src + *srcSizePtr; - const BYTE* const dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit; - const BYTE* const dictEnd = ctxPtr->dictBase + ctxPtr->dictLimit; + const BYTE* const dictBegin = ctxPtr->dictStart; + const BYTE* const dictEnd = ctxPtr->dictStart + (ctxPtr->dictLimit - ctxPtr->lowLimit); if ((sourceEnd > dictBegin) && ((const BYTE*)src < dictEnd)) { if (sourceEnd > dictEnd) sourceEnd = dictEnd; - ctxPtr->lowLimit = (U32)(sourceEnd - ctxPtr->dictBase); - if (ctxPtr->dictLimit - ctxPtr->lowLimit < 4) ctxPtr->lowLimit = ctxPtr->dictLimit; - } - } + ctxPtr->lowLimit += (U32)(sourceEnd - ctxPtr->dictStart); + ctxPtr->dictStart += (U32)(sourceEnd - ctxPtr->dictStart); + if (ctxPtr->dictLimit - ctxPtr->lowLimit < 4) { + ctxPtr->lowLimit = ctxPtr->dictLimit; + ctxPtr->dictStart = ctxPtr->prefixStart; + } } } return LZ4HC_compress_generic (ctxPtr, src, dst, srcSizePtr, dstCapacity, ctxPtr->compressionLevel, limit); } @@ -1121,23 +1163,31 @@ -/* dictionary saving */ - +/* LZ4_saveDictHC : + * save history content + * into a user-provided buffer + * which is then used to continue compression + */ int LZ4_saveDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, char* safeBuffer, int dictSize) { LZ4HC_CCtx_internal* const streamPtr = &LZ4_streamHCPtr->internal_donotuse; - int const prefixSize = (int)(streamPtr->end - (streamPtr->base + streamPtr->dictLimit)); - DEBUGLOG(4, "LZ4_saveDictHC(%p, %p, %d)", LZ4_streamHCPtr, safeBuffer, dictSize); + int const prefixSize = (int)(streamPtr->end - streamPtr->prefixStart); + DEBUGLOG(5, "LZ4_saveDictHC(%p, %p, %d)", LZ4_streamHCPtr, safeBuffer, dictSize); + assert(prefixSize >= 0); if (dictSize > 64 KB) dictSize = 64 KB; if (dictSize < 4) dictSize = 0; if (dictSize > prefixSize) dictSize = prefixSize; - memmove(safeBuffer, streamPtr->end - dictSize, dictSize); - { U32 const endIndex = (U32)(streamPtr->end - streamPtr->base); + if (safeBuffer == NULL) assert(dictSize == 0); + if (dictSize > 0) + LZ4_memmove(safeBuffer, streamPtr->end - dictSize, dictSize); + { U32 const endIndex = (U32)(streamPtr->end - streamPtr->prefixStart) + streamPtr->dictLimit; streamPtr->end = (const BYTE*)safeBuffer + dictSize; - streamPtr->base = streamPtr->end - endIndex; + streamPtr->prefixStart = streamPtr->end - dictSize; streamPtr->dictLimit = endIndex - (U32)dictSize; streamPtr->lowLimit = endIndex - (U32)dictSize; - if (streamPtr->nextToUpdate < streamPtr->dictLimit) streamPtr->nextToUpdate = streamPtr->dictLimit; + streamPtr->dictStart = streamPtr->prefixStart; + if (streamPtr->nextToUpdate < streamPtr->dictLimit) + streamPtr->nextToUpdate = streamPtr->dictLimit; } return dictSize; } @@ -1163,7 +1213,7 @@ /* Deprecated streaming functions */ -int LZ4_sizeofStreamStateHC(void) { return LZ4_STREAMHCSIZE; } +int LZ4_sizeofStreamStateHC(void) { return sizeof(LZ4_streamHC_t); } /* state is presumed correctly sized, aka >= sizeof(LZ4_streamHC_t) * @return : 0 on success, !=0 if error */ @@ -1175,6 +1225,7 @@ return 0; } +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) void* LZ4_createHC (const char* inputBuffer) { LZ4_streamHC_t* const hc4 = LZ4_createStreamHC(); @@ -1189,6 +1240,7 @@ FREEMEM(LZ4HC_Data); return 0; } +#endif int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* src, char* dst, int srcSize, int cLevel) { @@ -1202,11 +1254,11 @@ char* LZ4_slideInputBufferHC(void* LZ4HC_Data) { - LZ4_streamHC_t *ctx = (LZ4_streamHC_t*)LZ4HC_Data; - const BYTE *bufferStart = ctx->internal_donotuse.base + ctx->internal_donotuse.lowLimit; + LZ4_streamHC_t* const ctx = (LZ4_streamHC_t*)LZ4HC_Data; + const BYTE* bufferStart = ctx->internal_donotuse.prefixStart - ctx->internal_donotuse.dictLimit + ctx->internal_donotuse.lowLimit; LZ4_resetStreamHC_fast(ctx, ctx->internal_donotuse.compressionLevel); /* avoid const char * -> char * conversion warning :( */ - return (char *)(uptrval)bufferStart; + return (char*)(uptrval)bufferStart; } @@ -1287,8 +1339,13 @@ const dictCtx_directive dict, const HCfavor_e favorDecSpeed) { + int retval = 0; #define TRAILING_LITERALS 3 +#if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 + LZ4HC_optimal_t* const opt = (LZ4HC_optimal_t*)ALLOC(sizeof(LZ4HC_optimal_t) * (LZ4_OPT_NUM + TRAILING_LITERALS)); +#else LZ4HC_optimal_t opt[LZ4_OPT_NUM + TRAILING_LITERALS]; /* ~64 KB, which is a bit large for stack... */ +#endif const BYTE* ip = (const BYTE*) source; const BYTE* anchor = ip; @@ -1298,15 +1355,19 @@ BYTE* op = (BYTE*) dst; BYTE* opSaved = (BYTE*) dst; BYTE* oend = op + dstCapacity; + int ovml = MINMATCH; /* overflow - last sequence */ + const BYTE* ovref = NULL; /* init */ +#if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 + if (opt == NULL) goto _return_label; +#endif DEBUGLOG(5, "LZ4HC_compress_optimal(dst=%p, dstCapa=%u)", dst, (unsigned)dstCapacity); *srcSizePtr = 0; if (limit == fillOutput) oend -= LASTLITERALS; /* Hack for support LZ4 format restriction */ if (sufficient_len >= LZ4_OPT_NUM) sufficient_len = LZ4_OPT_NUM-1; /* Main Loop */ - assert(ip - anchor < LZ4_MAX_INPUT_SIZE); while (ip <= mflimit) { int const llen = (int)(ip - anchor); int best_mlen, best_off; @@ -1320,8 +1381,11 @@ int const firstML = firstMatch.len; const BYTE* const matchPos = ip - firstMatch.off; opSaved = op; - if ( LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), firstML, matchPos, limit, oend) ) /* updates ip, op and anchor */ + if ( LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), firstML, matchPos, limit, oend) ) { /* updates ip, op and anchor */ + ovml = firstML; + ovref = matchPos; goto _dest_overflow; + } continue; } @@ -1463,7 +1527,7 @@ best_off = opt[last_match_pos].off; cur = last_match_pos - best_mlen; - encode: /* cur, last_match_pos, best_mlen, best_off must be set */ +encode: /* cur, last_match_pos, best_mlen, best_off must be set */ assert(cur < LZ4_OPT_NUM); assert(last_match_pos >= 1); /* == 1 when only one candidate */ DEBUGLOG(6, "reverse traversal, looking for shortest path (last_match_pos=%i)", last_match_pos); @@ -1493,25 +1557,31 @@ assert(ml >= MINMATCH); assert((offset >= 1) && (offset <= LZ4_DISTANCE_MAX)); opSaved = op; - if ( LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml, ip - offset, limit, oend) ) /* updates ip, op and anchor */ + if ( LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ml, ip - offset, limit, oend) ) { /* updates ip, op and anchor */ + ovml = ml; + ovref = ip - offset; goto _dest_overflow; - } } + } } } } /* while (ip <= mflimit) */ - _last_literals: +_last_literals: /* Encode Last Literals */ { size_t lastRunSize = (size_t)(iend - anchor); /* literals */ - size_t litLength = (lastRunSize + 255 - RUN_MASK) / 255; - size_t const totalSize = 1 + litLength + lastRunSize; + size_t llAdd = (lastRunSize + 255 - RUN_MASK) / 255; + size_t const totalSize = 1 + llAdd + lastRunSize; if (limit == fillOutput) oend += LASTLITERALS; /* restore correct value */ if (limit && (op + totalSize > oend)) { - if (limit == limitedOutput) return 0; /* Check output limit */ + if (limit == limitedOutput) { /* Check output limit */ + retval = 0; + goto _return_label; + } /* adapt lastRunSize to fill 'dst' */ - lastRunSize = (size_t)(oend - op) - 1; - litLength = (lastRunSize + 255 - RUN_MASK) / 255; - lastRunSize -= litLength; + lastRunSize = (size_t)(oend - op) - 1 /*token*/; + llAdd = (lastRunSize + 256 - RUN_MASK) / 256; + lastRunSize -= llAdd; } - ip = anchor + lastRunSize; + DEBUGLOG(6, "Final literal run : %i literals", (int)lastRunSize); + ip = anchor + lastRunSize; /* can be != iend if limit==fillOutput */ if (lastRunSize >= RUN_MASK) { size_t accumulator = lastRunSize - RUN_MASK; @@ -1521,18 +1591,41 @@ } else { *op++ = (BYTE)(lastRunSize << ML_BITS); } - memcpy(op, anchor, lastRunSize); + LZ4_memcpy(op, anchor, lastRunSize); op += lastRunSize; } /* End */ *srcSizePtr = (int) (((const char*)ip) - source); - return (int) ((char*)op-dst); + retval = (int) ((char*)op-dst); + goto _return_label; - _dest_overflow: - if (limit == fillOutput) { - op = opSaved; /* restore correct out pointer */ - goto _last_literals; - } - return 0; - } +_dest_overflow: +if (limit == fillOutput) { + /* Assumption : ip, anchor, ovml and ovref must be set correctly */ + size_t const ll = (size_t)(ip - anchor); + size_t const ll_addbytes = (ll + 240) / 255; + size_t const ll_totalCost = 1 + ll_addbytes + ll; + BYTE* const maxLitPos = oend - 3; /* 2 for offset, 1 for token */ + DEBUGLOG(6, "Last sequence overflowing (only %i bytes remaining)", (int)(oend-1-opSaved)); + op = opSaved; /* restore correct out pointer */ + if (op + ll_totalCost <= maxLitPos) { + /* ll validated; now adjust match length */ + size_t const bytesLeftForMl = (size_t)(maxLitPos - (op+ll_totalCost)); + size_t const maxMlSize = MINMATCH + (ML_MASK-1) + (bytesLeftForMl * 255); + assert(maxMlSize < INT_MAX); assert(ovml >= 0); + if ((size_t)ovml > maxMlSize) ovml = (int)maxMlSize; + if ((oend + LASTLITERALS) - (op + ll_totalCost + 2) - 1 + ovml >= MFLIMIT) { + DEBUGLOG(6, "Space to end : %i + ml (%i)", (int)((oend + LASTLITERALS) - (op + ll_totalCost + 2) - 1), ovml); + DEBUGLOG(6, "Before : ip = %p, anchor = %p", ip, anchor); + LZ4HC_encodeSequence(UPDATABLE(ip, op, anchor), ovml, ovref, notLimited, oend); + DEBUGLOG(6, "After : ip = %p, anchor = %p", ip, anchor); + } } + goto _last_literals; +} +_return_label: +#if defined(LZ4HC_HEAPMODE) && LZ4HC_HEAPMODE==1 + FREEMEM(opt); +#endif + return retval; +} diff --git a/cbits/lz4hc.h b/cbits/lz4hc.h --- a/cbits/lz4hc.h +++ b/cbits/lz4hc.h @@ -1,7 +1,7 @@ /* LZ4 HC - High Compression Mode of LZ4 Header File - Copyright (C) 2011-2017, Yann Collet. + Copyright (C) 2011-2020, 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 @@ -198,63 +198,36 @@ #define LZ4HC_HASH_MASK (LZ4HC_HASHTABLESIZE - 1) -#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) -#include - -typedef struct LZ4HC_CCtx_internal LZ4HC_CCtx_internal; -struct LZ4HC_CCtx_internal -{ - uint32_t hashTable[LZ4HC_HASHTABLESIZE]; - uint16_t chainTable[LZ4HC_MAXD]; - const uint8_t* end; /* next block here to continue on current prefix */ - const uint8_t* base; /* All index relative to this position */ - const uint8_t* dictBase; /* alternate base for extDict */ - uint32_t dictLimit; /* below that point, need extDict */ - uint32_t lowLimit; /* below that point, no more dict */ - uint32_t nextToUpdate; /* index from which to continue dictionary update */ - short compressionLevel; - int8_t favorDecSpeed; /* favor decompression speed if this flag set, - otherwise, favor compression ratio */ - int8_t dirty; /* stream has to be fully reset if this flag is set */ - const LZ4HC_CCtx_internal* dictCtx; -}; - -#else - +/* Never ever use these definitions directly ! + * Declare or allocate an LZ4_streamHC_t instead. +**/ typedef struct LZ4HC_CCtx_internal LZ4HC_CCtx_internal; struct LZ4HC_CCtx_internal { - unsigned int hashTable[LZ4HC_HASHTABLESIZE]; - unsigned short chainTable[LZ4HC_MAXD]; - const unsigned char* end; /* next block here to continue on current prefix */ - const unsigned char* base; /* All index relative to this position */ - const unsigned char* dictBase; /* alternate base for extDict */ - unsigned int dictLimit; /* below that point, need extDict */ - unsigned int lowLimit; /* below that point, no more dict */ - unsigned int nextToUpdate; /* index from which to continue dictionary update */ - short compressionLevel; - char favorDecSpeed; /* favor decompression speed if this flag set, - otherwise, favor compression ratio */ - char dirty; /* stream has to be fully reset if this flag is set */ + LZ4_u32 hashTable[LZ4HC_HASHTABLESIZE]; + LZ4_u16 chainTable[LZ4HC_MAXD]; + const LZ4_byte* end; /* next block here to continue on current prefix */ + const LZ4_byte* prefixStart; /* Indexes relative to this position */ + const LZ4_byte* dictStart; /* alternate reference for extDict */ + LZ4_u32 dictLimit; /* below that point, need extDict */ + LZ4_u32 lowLimit; /* below that point, no more dict */ + LZ4_u32 nextToUpdate; /* index from which to continue dictionary update */ + short compressionLevel; + LZ4_i8 favorDecSpeed; /* favor decompression speed if this flag set, + otherwise, favor compression ratio */ + LZ4_i8 dirty; /* stream has to be fully reset if this flag is set */ const LZ4HC_CCtx_internal* dictCtx; }; -#endif - - -/* Do not use these definitions directly ! - * Declare or allocate an LZ4_streamHC_t instead. - */ -#define LZ4_STREAMHCSIZE (4*LZ4HC_HASHTABLESIZE + 2*LZ4HC_MAXD + 56 + ((sizeof(void*)==16) ? 56 : 0) /* AS400*/ ) /* 262200 or 262256*/ -#define LZ4_STREAMHCSIZE_SIZET (LZ4_STREAMHCSIZE / sizeof(size_t)) +#define LZ4_STREAMHC_MINSIZE 262200 /* static size, for inter-version compatibility */ union LZ4_streamHC_u { - size_t table[LZ4_STREAMHCSIZE_SIZET]; + char minStateSize[LZ4_STREAMHC_MINSIZE]; LZ4HC_CCtx_internal internal_donotuse; }; /* previously typedef'd to LZ4_streamHC_t */ /* LZ4_streamHC_t : * This structure allows static allocation of LZ4 HC streaming state. - * This can be used to allocate statically, on state, or as part of a larger structure. + * This can be used to allocate statically on stack, or as part of a larger structure. * * Such state **must** be initialized using LZ4_initStreamHC() before first use. * @@ -269,7 +242,7 @@ * Required before first use of a statically allocated LZ4_streamHC_t. * Before v1.9.0 : use LZ4_resetStreamHC() instead */ -LZ4LIB_API LZ4_streamHC_t* LZ4_initStreamHC (void* buffer, size_t size); +LZ4LIB_API LZ4_streamHC_t* LZ4_initStreamHC(void* buffer, size_t size); /*-************************************ @@ -297,9 +270,11 @@ * LZ4_slideInputBufferHC() will truncate the history of the stream, rather * than preserve a window-sized chunk of history. */ +#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) LZ4_DEPRECATED("use LZ4_createStreamHC() instead") LZ4LIB_API void* LZ4_createHC (const char* inputBuffer); -LZ4_DEPRECATED("use LZ4_saveDictHC() instead") LZ4LIB_API char* LZ4_slideInputBufferHC (void* LZ4HC_Data); LZ4_DEPRECATED("use LZ4_freeStreamHC() instead") LZ4LIB_API int LZ4_freeHC (void* LZ4HC_Data); +#endif +LZ4_DEPRECATED("use LZ4_saveDictHC() instead") LZ4LIB_API char* LZ4_slideInputBufferHC (void* LZ4HC_Data); LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel); LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel); LZ4_DEPRECATED("use LZ4_createStreamHC() instead") LZ4LIB_API int LZ4_sizeofStreamStateHC(void); @@ -330,7 +305,7 @@ * They should not be linked from DLL, * as there is no guarantee of API stability yet. * Prototypes will be promoted to "stable" status - * after successfull usage in real-life scenarios. + * after successful usage in real-life scenarios. ***************************************************/ #ifdef LZ4_HC_STATIC_LINKING_ONLY /* protection macro */ #ifndef LZ4_HC_SLO_098092834 diff --git a/cbits/xxhash.c b/cbits/xxhash.c new file mode 100644 --- /dev/null +++ b/cbits/xxhash.c @@ -0,0 +1,1030 @@ +/* +* xxHash - Fast Hash algorithm +* Copyright (C) 2012-2016, 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 : +* - xxHash homepage: http://www.xxhash.com +* - xxHash source repository : https://github.com/Cyan4973/xxHash +*/ + + +/* ************************************* +* Tuning parameters +***************************************/ +/*!XXH_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 doesn't depend on compiler but violate C standard. + * It can generate buggy code on targets which do not support unaligned memory accesses. + * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) + * See http://stackoverflow.com/a/32095106/646947 for details. + * Prefer these methods in priority order (0 > 1 > 2) + */ +#ifndef XXH_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 XXH_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 XXH_FORCE_MEMORY_ACCESS 1 +# endif +#endif + +/*!XXH_ACCEPT_NULL_INPUT_POINTER : + * If input pointer is NULL, xxHash default behavior is to dereference it, triggering a segfault. + * When this macro is enabled, xxHash actively checks input for null pointer. + * It it is, result for null input pointers is the same as a null-length input. + */ +#ifndef XXH_ACCEPT_NULL_INPUT_POINTER /* can be defined externally */ +# define XXH_ACCEPT_NULL_INPUT_POINTER 0 +#endif + +/*!XXH_FORCE_NATIVE_FORMAT : + * By default, xxHash library provides endian-independent Hash values, based on little-endian convention. + * Results are therefore identical for little-endian and big-endian CPU. + * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format. + * Should endian-independence be of no importance for your application, you may set the #define below to 1, + * to improve speed for Big-endian CPU. + * This option has no impact on Little_Endian CPU. + */ +#ifndef XXH_FORCE_NATIVE_FORMAT /* can be defined externally */ +# define XXH_FORCE_NATIVE_FORMAT 0 +#endif + +/*!XXH_FORCE_ALIGN_CHECK : + * This is a minor performance trick, only useful with lots of very small keys. + * It means : check for aligned/unaligned input. + * The check costs one initial branch per hash; + * set it to 0 when the input is guaranteed to be aligned, + * or when alignment doesn't matter for performance. + */ +#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */ +# if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64) +# define XXH_FORCE_ALIGN_CHECK 0 +# else +# define XXH_FORCE_ALIGN_CHECK 1 +# endif +#endif + + +/* ************************************* +* Includes & Memory related functions +***************************************/ +/*! Modify the local functions below should you wish to use some other memory routines +* for malloc(), free() */ +#include +static void* XXH_malloc(size_t s) { return malloc(s); } +static void XXH_free (void* p) { free(p); } +/*! and for memcpy() */ +#include +static void* XXH_memcpy(void* dest, const void* src, size_t size) { return memcpy(dest,src,size); } + +#include /* assert */ + +#define XXH_STATIC_LINKING_ONLY +#include "xxhash.h" + + +/* ************************************* +* Compiler Specific Options +***************************************/ +#ifdef _MSC_VER /* Visual Studio */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +# define FORCE_INLINE static __forceinline +#else +# 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 + + +/* ************************************* +* Basic Types +***************************************/ +#ifndef MEM_MODULE +# if !defined (__VMS) \ + && (defined (__cplusplus) \ + || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) +# include + typedef uint8_t BYTE; + typedef uint16_t U16; + typedef uint32_t U32; +# else + typedef unsigned char BYTE; + typedef unsigned short U16; + typedef unsigned int U32; +# endif +#endif + +#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2)) + +/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */ +static U32 XXH_read32(const void* memPtr) { return *(const U32*) memPtr; } + +#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_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 { U32 u32; } __attribute__((packed)) unalign; +static U32 XXH_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } + +#else + +/* portable and safe solution. Generally efficient. + * see : http://stackoverflow.com/a/32095106/646947 + */ +static U32 XXH_read32(const void* memPtr) +{ + U32 val; + memcpy(&val, memPtr, sizeof(val)); + return val; +} + +#endif /* XXH_FORCE_DIRECT_MEMORY_ACCESS */ + + +/* **************************************** +* Compiler-specific Functions and Macros +******************************************/ +#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) + +/* Note : although _rotl exists for minGW (GCC under windows), performance seems poor */ +#if defined(_MSC_VER) +# define XXH_rotl32(x,r) _rotl(x,r) +# define XXH_rotl64(x,r) _rotl64(x,r) +#else +# define XXH_rotl32(x,r) ((x << r) | (x >> (32 - r))) +# define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r))) +#endif + +#if defined(_MSC_VER) /* Visual Studio */ +# define XXH_swap32 _byteswap_ulong +#elif XXH_GCC_VERSION >= 403 +# define XXH_swap32 __builtin_bswap32 +#else +static U32 XXH_swap32 (U32 x) +{ + return ((x << 24) & 0xff000000 ) | + ((x << 8) & 0x00ff0000 ) | + ((x >> 8) & 0x0000ff00 ) | + ((x >> 24) & 0x000000ff ); +} +#endif + + +/* ************************************* +* Architecture Macros +***************************************/ +typedef enum { XXH_bigEndian=0, XXH_littleEndian=1 } XXH_endianess; + +/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */ +#ifndef XXH_CPU_LITTLE_ENDIAN +static int XXH_isLittleEndian(void) +{ + const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ + return one.c[0]; +} +# define XXH_CPU_LITTLE_ENDIAN XXH_isLittleEndian() +#endif + + +/* *************************** +* Memory reads +*****************************/ +typedef enum { XXH_aligned, XXH_unaligned } XXH_alignment; + +FORCE_INLINE U32 XXH_readLE32_align(const void* ptr, XXH_endianess endian, XXH_alignment align) +{ + if (align==XXH_unaligned) + return endian==XXH_littleEndian ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr)); + else + return endian==XXH_littleEndian ? *(const U32*)ptr : XXH_swap32(*(const U32*)ptr); +} + +FORCE_INLINE U32 XXH_readLE32(const void* ptr, XXH_endianess endian) +{ + return XXH_readLE32_align(ptr, endian, XXH_unaligned); +} + +static U32 XXH_readBE32(const void* ptr) +{ + return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr); +} + + +/* ************************************* +* Macros +***************************************/ +#define XXH_STATIC_ASSERT(c) { enum { XXH_sa = 1/(int)(!!(c)) }; } /* use after variable declarations */ +XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; } + + +/* ******************************************************************* +* 32-bit hash functions +*********************************************************************/ +static const U32 PRIME32_1 = 2654435761U; +static const U32 PRIME32_2 = 2246822519U; +static const U32 PRIME32_3 = 3266489917U; +static const U32 PRIME32_4 = 668265263U; +static const U32 PRIME32_5 = 374761393U; + +static U32 XXH32_round(U32 seed, U32 input) +{ + seed += input * PRIME32_2; + seed = XXH_rotl32(seed, 13); + seed *= PRIME32_1; + return seed; +} + +/* mix all bits */ +static U32 XXH32_avalanche(U32 h32) +{ + h32 ^= h32 >> 15; + h32 *= PRIME32_2; + h32 ^= h32 >> 13; + h32 *= PRIME32_3; + h32 ^= h32 >> 16; + return(h32); +} + +#define XXH_get32bits(p) XXH_readLE32_align(p, endian, align) + +static U32 +XXH32_finalize(U32 h32, const void* ptr, size_t len, + XXH_endianess endian, XXH_alignment align) + +{ + const BYTE* p = (const BYTE*)ptr; + +#define PROCESS1 \ + h32 += (*p++) * PRIME32_5; \ + h32 = XXH_rotl32(h32, 11) * PRIME32_1 ; + +#define PROCESS4 \ + h32 += XXH_get32bits(p) * PRIME32_3; \ + p+=4; \ + h32 = XXH_rotl32(h32, 17) * PRIME32_4 ; + + switch(len&15) /* or switch(bEnd - p) */ + { + case 12: PROCESS4; + /* fallthrough */ + case 8: PROCESS4; + /* fallthrough */ + case 4: PROCESS4; + return XXH32_avalanche(h32); + + case 13: PROCESS4; + /* fallthrough */ + case 9: PROCESS4; + /* fallthrough */ + case 5: PROCESS4; + PROCESS1; + return XXH32_avalanche(h32); + + case 14: PROCESS4; + /* fallthrough */ + case 10: PROCESS4; + /* fallthrough */ + case 6: PROCESS4; + PROCESS1; + PROCESS1; + return XXH32_avalanche(h32); + + case 15: PROCESS4; + /* fallthrough */ + case 11: PROCESS4; + /* fallthrough */ + case 7: PROCESS4; + /* fallthrough */ + case 3: PROCESS1; + /* fallthrough */ + case 2: PROCESS1; + /* fallthrough */ + case 1: PROCESS1; + /* fallthrough */ + case 0: return XXH32_avalanche(h32); + } + assert(0); + return h32; /* reaching this point is deemed impossible */ +} + + +FORCE_INLINE U32 +XXH32_endian_align(const void* input, size_t len, U32 seed, + XXH_endianess endian, XXH_alignment align) +{ + const BYTE* p = (const BYTE*)input; + const BYTE* bEnd = p + len; + U32 h32; + +#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1) + if (p==NULL) { + len=0; + bEnd=p=(const BYTE*)(size_t)16; + } +#endif + + if (len>=16) { + const BYTE* const limit = bEnd - 15; + U32 v1 = seed + PRIME32_1 + PRIME32_2; + U32 v2 = seed + PRIME32_2; + U32 v3 = seed + 0; + U32 v4 = seed - PRIME32_1; + + do { + v1 = XXH32_round(v1, XXH_get32bits(p)); p+=4; + v2 = XXH32_round(v2, XXH_get32bits(p)); p+=4; + v3 = XXH32_round(v3, XXH_get32bits(p)); p+=4; + v4 = XXH32_round(v4, XXH_get32bits(p)); p+=4; + } while (p < limit); + + h32 = XXH_rotl32(v1, 1) + XXH_rotl32(v2, 7) + + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18); + } else { + h32 = seed + PRIME32_5; + } + + h32 += (U32)len; + + return XXH32_finalize(h32, p, len&15, endian, align); +} + + +XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int seed) +{ +#if 0 + /* Simple version, good for code maintenance, but unfortunately slow for small inputs */ + XXH32_state_t state; + XXH32_reset(&state, seed); + XXH32_update(&state, input, len); + return XXH32_digest(&state); +#else + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if (XXH_FORCE_ALIGN_CHECK) { + if ((((size_t)input) & 3) == 0) { /* Input is 4-bytes aligned, leverage the speed benefit */ + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned); + else + return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned); + } } + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned); + else + return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned); +#endif +} + + + +/*====== Hash streaming ======*/ + +XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void) +{ + return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t)); +} +XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr) +{ + XXH_free(statePtr); + return XXH_OK; +} + +XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState) +{ + memcpy(dstState, srcState, sizeof(*dstState)); +} + +XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, unsigned int seed) +{ + XXH32_state_t state; /* using a local state to memcpy() in order to avoid strict-aliasing warnings */ + memset(&state, 0, sizeof(state)); + state.v1 = seed + PRIME32_1 + PRIME32_2; + state.v2 = seed + PRIME32_2; + state.v3 = seed + 0; + state.v4 = seed - PRIME32_1; + /* do not write into reserved, planned to be removed in a future version */ + memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved)); + return XXH_OK; +} + + +FORCE_INLINE XXH_errorcode +XXH32_update_endian(XXH32_state_t* state, const void* input, size_t len, XXH_endianess endian) +{ + if (input==NULL) +#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1) + return XXH_OK; +#else + return XXH_ERROR; +#endif + + { const BYTE* p = (const BYTE*)input; + const BYTE* const bEnd = p + len; + + state->total_len_32 += (unsigned)len; + state->large_len |= (len>=16) | (state->total_len_32>=16); + + if (state->memsize + len < 16) { /* fill in tmp buffer */ + XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len); + state->memsize += (unsigned)len; + return XXH_OK; + } + + if (state->memsize) { /* some data left from previous update */ + XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, 16-state->memsize); + { const U32* p32 = state->mem32; + state->v1 = XXH32_round(state->v1, XXH_readLE32(p32, endian)); p32++; + state->v2 = XXH32_round(state->v2, XXH_readLE32(p32, endian)); p32++; + state->v3 = XXH32_round(state->v3, XXH_readLE32(p32, endian)); p32++; + state->v4 = XXH32_round(state->v4, XXH_readLE32(p32, endian)); + } + p += 16-state->memsize; + state->memsize = 0; + } + + if (p <= bEnd-16) { + const BYTE* const limit = bEnd - 16; + U32 v1 = state->v1; + U32 v2 = state->v2; + U32 v3 = state->v3; + U32 v4 = state->v4; + + do { + v1 = XXH32_round(v1, XXH_readLE32(p, endian)); p+=4; + v2 = XXH32_round(v2, XXH_readLE32(p, endian)); p+=4; + v3 = XXH32_round(v3, XXH_readLE32(p, endian)); p+=4; + v4 = XXH32_round(v4, XXH_readLE32(p, endian)); p+=4; + } while (p<=limit); + + state->v1 = v1; + state->v2 = v2; + state->v3 = v3; + state->v4 = v4; + } + + if (p < bEnd) { + XXH_memcpy(state->mem32, p, (size_t)(bEnd-p)); + state->memsize = (unsigned)(bEnd-p); + } + } + + return XXH_OK; +} + + +XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void* input, size_t len) +{ + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH32_update_endian(state_in, input, len, XXH_littleEndian); + else + return XXH32_update_endian(state_in, input, len, XXH_bigEndian); +} + + +FORCE_INLINE U32 +XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian) +{ + U32 h32; + + if (state->large_len) { + h32 = XXH_rotl32(state->v1, 1) + + XXH_rotl32(state->v2, 7) + + XXH_rotl32(state->v3, 12) + + XXH_rotl32(state->v4, 18); + } else { + h32 = state->v3 /* == seed */ + PRIME32_5; + } + + h32 += state->total_len_32; + + return XXH32_finalize(h32, state->mem32, state->memsize, endian, XXH_aligned); +} + + +XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in) +{ + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH32_digest_endian(state_in, XXH_littleEndian); + else + return XXH32_digest_endian(state_in, XXH_bigEndian); +} + + +/*====== Canonical representation ======*/ + +/*! Default XXH result types are basic unsigned 32 and 64 bits. +* The canonical representation follows human-readable write convention, aka big-endian (large digits first). +* These functions allow transformation of hash result into and from its canonical format. +* This way, hash values can be written into a file or buffer, remaining comparable across different systems. +*/ + +XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash) +{ + XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t)); + if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash); + memcpy(dst, &hash, sizeof(*dst)); +} + +XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src) +{ + return XXH_readBE32(src); +} + + +#ifndef XXH_NO_LONG_LONG + +/* ******************************************************************* +* 64-bit hash functions +*********************************************************************/ + +/*====== Memory access ======*/ + +#ifndef MEM_MODULE +# define MEM_MODULE +# if !defined (__VMS) \ + && (defined (__cplusplus) \ + || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) +# include + typedef uint64_t U64; +# else + /* if compiler doesn't support unsigned long long, replace by another 64-bit type */ + typedef unsigned long long U64; +# endif +#endif + + +#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2)) + +/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */ +static U64 XXH_read64(const void* memPtr) { return *(const U64*) memPtr; } + +#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_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 { U32 u32; U64 u64; } __attribute__((packed)) unalign64; +static U64 XXH_read64(const void* ptr) { return ((const unalign64*)ptr)->u64; } + +#else + +/* portable and safe solution. Generally efficient. + * see : http://stackoverflow.com/a/32095106/646947 + */ + +static U64 XXH_read64(const void* memPtr) +{ + U64 val; + memcpy(&val, memPtr, sizeof(val)); + return val; +} + +#endif /* XXH_FORCE_DIRECT_MEMORY_ACCESS */ + +#if defined(_MSC_VER) /* Visual Studio */ +# define XXH_swap64 _byteswap_uint64 +#elif XXH_GCC_VERSION >= 403 +# define XXH_swap64 __builtin_bswap64 +#else +static U64 XXH_swap64 (U64 x) +{ + return ((x << 56) & 0xff00000000000000ULL) | + ((x << 40) & 0x00ff000000000000ULL) | + ((x << 24) & 0x0000ff0000000000ULL) | + ((x << 8) & 0x000000ff00000000ULL) | + ((x >> 8) & 0x00000000ff000000ULL) | + ((x >> 24) & 0x0000000000ff0000ULL) | + ((x >> 40) & 0x000000000000ff00ULL) | + ((x >> 56) & 0x00000000000000ffULL); +} +#endif + +FORCE_INLINE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align) +{ + if (align==XXH_unaligned) + return endian==XXH_littleEndian ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr)); + else + return endian==XXH_littleEndian ? *(const U64*)ptr : XXH_swap64(*(const U64*)ptr); +} + +FORCE_INLINE U64 XXH_readLE64(const void* ptr, XXH_endianess endian) +{ + return XXH_readLE64_align(ptr, endian, XXH_unaligned); +} + +static U64 XXH_readBE64(const void* ptr) +{ + return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr); +} + + +/*====== xxh64 ======*/ + +static const U64 PRIME64_1 = 11400714785074694791ULL; +static const U64 PRIME64_2 = 14029467366897019727ULL; +static const U64 PRIME64_3 = 1609587929392839161ULL; +static const U64 PRIME64_4 = 9650029242287828579ULL; +static const U64 PRIME64_5 = 2870177450012600261ULL; + +static U64 XXH64_round(U64 acc, U64 input) +{ + acc += input * PRIME64_2; + acc = XXH_rotl64(acc, 31); + acc *= PRIME64_1; + return acc; +} + +static U64 XXH64_mergeRound(U64 acc, U64 val) +{ + val = XXH64_round(0, val); + acc ^= val; + acc = acc * PRIME64_1 + PRIME64_4; + return acc; +} + +static U64 XXH64_avalanche(U64 h64) +{ + h64 ^= h64 >> 33; + h64 *= PRIME64_2; + h64 ^= h64 >> 29; + h64 *= PRIME64_3; + h64 ^= h64 >> 32; + return h64; +} + + +#define XXH_get64bits(p) XXH_readLE64_align(p, endian, align) + +static U64 +XXH64_finalize(U64 h64, const void* ptr, size_t len, + XXH_endianess endian, XXH_alignment align) +{ + const BYTE* p = (const BYTE*)ptr; + +#define PROCESS1_64 \ + h64 ^= (*p++) * PRIME64_5; \ + h64 = XXH_rotl64(h64, 11) * PRIME64_1; + +#define PROCESS4_64 \ + h64 ^= (U64)(XXH_get32bits(p)) * PRIME64_1; \ + p+=4; \ + h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; + +#define PROCESS8_64 { \ + U64 const k1 = XXH64_round(0, XXH_get64bits(p)); \ + p+=8; \ + h64 ^= k1; \ + h64 = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4; \ +} + + switch(len&31) { + case 24: PROCESS8_64; + /* fallthrough */ + case 16: PROCESS8_64; + /* fallthrough */ + case 8: PROCESS8_64; + return XXH64_avalanche(h64); + + case 28: PROCESS8_64; + /* fallthrough */ + case 20: PROCESS8_64; + /* fallthrough */ + case 12: PROCESS8_64; + /* fallthrough */ + case 4: PROCESS4_64; + return XXH64_avalanche(h64); + + case 25: PROCESS8_64; + /* fallthrough */ + case 17: PROCESS8_64; + /* fallthrough */ + case 9: PROCESS8_64; + PROCESS1_64; + return XXH64_avalanche(h64); + + case 29: PROCESS8_64; + /* fallthrough */ + case 21: PROCESS8_64; + /* fallthrough */ + case 13: PROCESS8_64; + /* fallthrough */ + case 5: PROCESS4_64; + PROCESS1_64; + return XXH64_avalanche(h64); + + case 26: PROCESS8_64; + /* fallthrough */ + case 18: PROCESS8_64; + /* fallthrough */ + case 10: PROCESS8_64; + PROCESS1_64; + PROCESS1_64; + return XXH64_avalanche(h64); + + case 30: PROCESS8_64; + /* fallthrough */ + case 22: PROCESS8_64; + /* fallthrough */ + case 14: PROCESS8_64; + /* fallthrough */ + case 6: PROCESS4_64; + PROCESS1_64; + PROCESS1_64; + return XXH64_avalanche(h64); + + case 27: PROCESS8_64; + /* fallthrough */ + case 19: PROCESS8_64; + /* fallthrough */ + case 11: PROCESS8_64; + PROCESS1_64; + PROCESS1_64; + PROCESS1_64; + return XXH64_avalanche(h64); + + case 31: PROCESS8_64; + /* fallthrough */ + case 23: PROCESS8_64; + /* fallthrough */ + case 15: PROCESS8_64; + /* fallthrough */ + case 7: PROCESS4_64; + /* fallthrough */ + case 3: PROCESS1_64; + /* fallthrough */ + case 2: PROCESS1_64; + /* fallthrough */ + case 1: PROCESS1_64; + /* fallthrough */ + case 0: return XXH64_avalanche(h64); + } + + /* impossible to reach */ + assert(0); + return 0; /* unreachable, but some compilers complain without it */ +} + +FORCE_INLINE U64 +XXH64_endian_align(const void* input, size_t len, U64 seed, + XXH_endianess endian, XXH_alignment align) +{ + const BYTE* p = (const BYTE*)input; + const BYTE* bEnd = p + len; + U64 h64; + +#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1) + if (p==NULL) { + len=0; + bEnd=p=(const BYTE*)(size_t)32; + } +#endif + + if (len>=32) { + const BYTE* const limit = bEnd - 32; + U64 v1 = seed + PRIME64_1 + PRIME64_2; + U64 v2 = seed + PRIME64_2; + U64 v3 = seed + 0; + U64 v4 = seed - PRIME64_1; + + do { + v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8; + v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8; + v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8; + v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8; + } while (p<=limit); + + h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18); + h64 = XXH64_mergeRound(h64, v1); + h64 = XXH64_mergeRound(h64, v2); + h64 = XXH64_mergeRound(h64, v3); + h64 = XXH64_mergeRound(h64, v4); + + } else { + h64 = seed + PRIME64_5; + } + + h64 += (U64) len; + + return XXH64_finalize(h64, p, len, endian, align); +} + + +XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned long long seed) +{ +#if 0 + /* Simple version, good for code maintenance, but unfortunately slow for small inputs */ + XXH64_state_t state; + XXH64_reset(&state, seed); + XXH64_update(&state, input, len); + return XXH64_digest(&state); +#else + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if (XXH_FORCE_ALIGN_CHECK) { + if ((((size_t)input) & 7)==0) { /* Input is aligned, let's leverage the speed advantage */ + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned); + else + return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned); + } } + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned); + else + return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned); +#endif +} + +/*====== Hash Streaming ======*/ + +XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void) +{ + return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t)); +} +XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr) +{ + XXH_free(statePtr); + return XXH_OK; +} + +XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState) +{ + memcpy(dstState, srcState, sizeof(*dstState)); +} + +XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, unsigned long long seed) +{ + XXH64_state_t state; /* using a local state to memcpy() in order to avoid strict-aliasing warnings */ + memset(&state, 0, sizeof(state)); + state.v1 = seed + PRIME64_1 + PRIME64_2; + state.v2 = seed + PRIME64_2; + state.v3 = seed + 0; + state.v4 = seed - PRIME64_1; + /* do not write into reserved, planned to be removed in a future version */ + memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved)); + return XXH_OK; +} + +FORCE_INLINE XXH_errorcode +XXH64_update_endian (XXH64_state_t* state, const void* input, size_t len, XXH_endianess endian) +{ + if (input==NULL) +#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1) + return XXH_OK; +#else + return XXH_ERROR; +#endif + + { const BYTE* p = (const BYTE*)input; + const BYTE* const bEnd = p + len; + + state->total_len += len; + + if (state->memsize + len < 32) { /* fill in tmp buffer */ + XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, len); + state->memsize += (U32)len; + return XXH_OK; + } + + if (state->memsize) { /* tmp buffer is full */ + XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize); + state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian)); + state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian)); + state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian)); + state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian)); + p += 32-state->memsize; + state->memsize = 0; + } + + if (p+32 <= bEnd) { + const BYTE* const limit = bEnd - 32; + U64 v1 = state->v1; + U64 v2 = state->v2; + U64 v3 = state->v3; + U64 v4 = state->v4; + + do { + v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8; + v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8; + v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8; + v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8; + } while (p<=limit); + + state->v1 = v1; + state->v2 = v2; + state->v3 = v3; + state->v4 = v4; + } + + if (p < bEnd) { + XXH_memcpy(state->mem64, p, (size_t)(bEnd-p)); + state->memsize = (unsigned)(bEnd-p); + } + } + + return XXH_OK; +} + +XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void* input, size_t len) +{ + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH64_update_endian(state_in, input, len, XXH_littleEndian); + else + return XXH64_update_endian(state_in, input, len, XXH_bigEndian); +} + +FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian) +{ + U64 h64; + + if (state->total_len >= 32) { + U64 const v1 = state->v1; + U64 const v2 = state->v2; + U64 const v3 = state->v3; + U64 const v4 = state->v4; + + h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18); + h64 = XXH64_mergeRound(h64, v1); + h64 = XXH64_mergeRound(h64, v2); + h64 = XXH64_mergeRound(h64, v3); + h64 = XXH64_mergeRound(h64, v4); + } else { + h64 = state->v3 /*seed*/ + PRIME64_5; + } + + h64 += (U64) state->total_len; + + return XXH64_finalize(h64, state->mem64, (size_t)state->total_len, endian, XXH_aligned); +} + +XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in) +{ + XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN; + + if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT) + return XXH64_digest_endian(state_in, XXH_littleEndian); + else + return XXH64_digest_endian(state_in, XXH_bigEndian); +} + + +/*====== Canonical representation ======*/ + +XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash) +{ + XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t)); + if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash); + memcpy(dst, &hash, sizeof(*dst)); +} + +XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src) +{ + return XXH_readBE64(src); +} + +#endif /* XXH_NO_LONG_LONG */ diff --git a/cbits/xxhash.h b/cbits/xxhash.h new file mode 100644 --- /dev/null +++ b/cbits/xxhash.h @@ -0,0 +1,328 @@ +/* + xxHash - Extremely Fast Hash algorithm + Header File + Copyright (C) 2012-2016, 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 : + - xxHash source repository : https://github.com/Cyan4973/xxHash +*/ + +/* Notice extracted from xxHash homepage : + +xxHash is an extremely fast Hash algorithm, running at RAM speed limits. +It also successfully passes all tests from the SMHasher suite. + +Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz) + +Name Speed Q.Score Author +xxHash 5.4 GB/s 10 +CrapWow 3.2 GB/s 2 Andrew +MumurHash 3a 2.7 GB/s 10 Austin Appleby +SpookyHash 2.0 GB/s 10 Bob Jenkins +SBox 1.4 GB/s 9 Bret Mulvey +Lookup3 1.2 GB/s 9 Bob Jenkins +SuperFastHash 1.2 GB/s 1 Paul Hsieh +CityHash64 1.05 GB/s 10 Pike & Alakuijala +FNV 0.55 GB/s 5 Fowler, Noll, Vo +CRC32 0.43 GB/s 9 +MD5-32 0.33 GB/s 10 Ronald L. Rivest +SHA1-32 0.28 GB/s 10 + +Q.Score is a measure of quality of the hash function. +It depends on successfully passing SMHasher test set. +10 is a perfect score. + +A 64-bit version, named XXH64, is available since r35. +It offers much better speed, but for 64-bit applications only. +Name Speed on 64 bits Speed on 32 bits +XXH64 13.8 GB/s 1.9 GB/s +XXH32 6.8 GB/s 6.0 GB/s +*/ + +#ifndef XXHASH_H_5627135585666179 +#define XXHASH_H_5627135585666179 1 + +#if defined (__cplusplus) +extern "C" { +#endif + + +/* **************************** +* Definitions +******************************/ +#include /* size_t */ +typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode; + + +/* **************************** + * API modifier + ******************************/ +/** XXH_INLINE_ALL (and XXH_PRIVATE_API) + * This is useful to include xxhash functions in `static` mode + * in order to inline them, and remove their symbol from the public list. + * Inlining can offer dramatic performance improvement on small keys. + * Methodology : + * #define XXH_INLINE_ALL + * #include "xxhash.h" + * `xxhash.c` is automatically included. + * It's not useful to compile and link it as a separate module. + */ +#if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API) +# ifndef XXH_STATIC_LINKING_ONLY +# define XXH_STATIC_LINKING_ONLY +# endif +# if defined(__GNUC__) +# define XXH_PUBLIC_API static __inline __attribute__((unused)) +# elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +# define XXH_PUBLIC_API static inline +# elif defined(_MSC_VER) +# define XXH_PUBLIC_API static __inline +# else + /* this version may generate warnings for unused static functions */ +# define XXH_PUBLIC_API static +# endif +#else +# define XXH_PUBLIC_API /* do nothing */ +#endif /* XXH_INLINE_ALL || XXH_PRIVATE_API */ + +/*! XXH_NAMESPACE, aka Namespace Emulation : + * + * If you want to include _and expose_ xxHash functions from within your own library, + * but also want to avoid symbol collisions with other libraries which may also include xxHash, + * + * you can use XXH_NAMESPACE, to automatically prefix any public symbol from xxhash library + * with the value of XXH_NAMESPACE (therefore, avoid NULL and numeric values). + * + * Note that no change is required within the calling program as long as it includes `xxhash.h` : + * regular symbol name will be automatically translated by this header. + */ +#ifdef XXH_NAMESPACE +# define XXH_CAT(A,B) A##B +# define XXH_NAME2(A,B) XXH_CAT(A,B) +# define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber) +# define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32) +# define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState) +# define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState) +# define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset) +# define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update) +# define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest) +# define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState) +# define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash) +# define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical) +# define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64) +# define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState) +# define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState) +# define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset) +# define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update) +# define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest) +# define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState) +# define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash) +# define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical) +#endif + + +/* ************************************* +* Version +***************************************/ +#define XXH_VERSION_MAJOR 0 +#define XXH_VERSION_MINOR 6 +#define XXH_VERSION_RELEASE 5 +#define XXH_VERSION_NUMBER (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE) +XXH_PUBLIC_API unsigned XXH_versionNumber (void); + + +/*-********************************************************************** +* 32-bit hash +************************************************************************/ +typedef unsigned int XXH32_hash_t; + +/*! XXH32() : + Calculate the 32-bit hash of sequence "length" bytes stored at memory address "input". + The memory between input & input+length must be valid (allocated and read-accessible). + "seed" can be used to alter the result predictably. + Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s */ +XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed); + +/*====== Streaming ======*/ +typedef struct XXH32_state_s XXH32_state_t; /* incomplete type */ +XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void); +XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr); +XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state); + +XXH_PUBLIC_API XXH_errorcode XXH32_reset (XXH32_state_t* statePtr, unsigned int seed); +XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length); +XXH_PUBLIC_API XXH32_hash_t XXH32_digest (const XXH32_state_t* statePtr); + +/* + * Streaming functions generate the xxHash of an input provided in multiple segments. + * Note that, for small input, they are slower than single-call functions, due to state management. + * For small inputs, prefer `XXH32()` and `XXH64()`, which are better optimized. + * + * XXH state must first be allocated, using XXH*_createState() . + * + * Start a new hash by initializing state with a seed, using XXH*_reset(). + * + * Then, feed the hash state by calling XXH*_update() as many times as necessary. + * The function returns an error code, with 0 meaning OK, and any other value meaning there is an error. + * + * Finally, a hash value can be produced anytime, by using XXH*_digest(). + * This function returns the nn-bits hash as an int or long long. + * + * It's still possible to continue inserting input into the hash state after a digest, + * and generate some new hashes later on, by calling again XXH*_digest(). + * + * When done, free XXH state space if it was allocated dynamically. + */ + +/*====== Canonical representation ======*/ + +typedef struct { unsigned char digest[4]; } XXH32_canonical_t; +XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash); +XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src); + +/* Default result type for XXH functions are primitive unsigned 32 and 64 bits. + * The canonical representation uses human-readable write convention, aka big-endian (large digits first). + * These functions allow transformation of hash result into and from its canonical format. + * This way, hash values can be written into a file / memory, and remain comparable on different systems and programs. + */ + + +#ifndef XXH_NO_LONG_LONG +/*-********************************************************************** +* 64-bit hash +************************************************************************/ +typedef unsigned long long XXH64_hash_t; + +/*! XXH64() : + Calculate the 64-bit hash of sequence of length "len" stored at memory address "input". + "seed" can be used to alter the result predictably. + This function runs faster on 64-bit systems, but slower on 32-bit systems (see benchmark). +*/ +XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed); + +/*====== Streaming ======*/ +typedef struct XXH64_state_s XXH64_state_t; /* incomplete type */ +XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void); +XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr); +XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state); + +XXH_PUBLIC_API XXH_errorcode XXH64_reset (XXH64_state_t* statePtr, unsigned long long seed); +XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length); +XXH_PUBLIC_API XXH64_hash_t XXH64_digest (const XXH64_state_t* statePtr); + +/*====== Canonical representation ======*/ +typedef struct { unsigned char digest[8]; } XXH64_canonical_t; +XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash); +XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src); +#endif /* XXH_NO_LONG_LONG */ + + + +#ifdef XXH_STATIC_LINKING_ONLY + +/* ================================================================================================ + This section contains declarations which are not guaranteed to remain stable. + They may change in future versions, becoming incompatible with a different version of the library. + These declarations should only be used with static linking. + Never use them in association with dynamic linking ! +=================================================================================================== */ + +/* These definitions are only present to allow + * static allocation of XXH state, on stack or in a struct for example. + * Never **ever** use members directly. */ + +#if !defined (__VMS) \ + && (defined (__cplusplus) \ + || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) +# include + +struct XXH32_state_s { + uint32_t total_len_32; + uint32_t large_len; + uint32_t v1; + uint32_t v2; + uint32_t v3; + uint32_t v4; + uint32_t mem32[4]; + uint32_t memsize; + uint32_t reserved; /* never read nor write, might be removed in a future version */ +}; /* typedef'd to XXH32_state_t */ + +struct XXH64_state_s { + uint64_t total_len; + uint64_t v1; + uint64_t v2; + uint64_t v3; + uint64_t v4; + uint64_t mem64[4]; + uint32_t memsize; + uint32_t reserved[2]; /* never read nor write, might be removed in a future version */ +}; /* typedef'd to XXH64_state_t */ + +# else + +struct XXH32_state_s { + unsigned total_len_32; + unsigned large_len; + unsigned v1; + unsigned v2; + unsigned v3; + unsigned v4; + unsigned mem32[4]; + unsigned memsize; + unsigned reserved; /* never read nor write, might be removed in a future version */ +}; /* typedef'd to XXH32_state_t */ + +# ifndef XXH_NO_LONG_LONG /* remove 64-bit support */ +struct XXH64_state_s { + unsigned long long total_len; + unsigned long long v1; + unsigned long long v2; + unsigned long long v3; + unsigned long long v4; + unsigned long long mem64[4]; + unsigned memsize; + unsigned reserved[2]; /* never read nor write, might be removed in a future version */ +}; /* typedef'd to XXH64_state_t */ +# endif + +# endif + + +#if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API) +# include "xxhash.c" /* include xxhash function bodies as `static`, for inlining */ +#endif + +#endif /* XXH_STATIC_LINKING_ONLY */ + + +#if defined (__cplusplus) +} +#endif + +#endif /* XXHASH_H_5627135585666179 */ diff --git a/lz4-bytes.cabal b/lz4-bytes.cabal --- a/lz4-bytes.cabal +++ b/lz4-bytes.cabal @@ -1,6 +1,6 @@ cabal-version: 2.2 name: lz4-bytes -version: 0.1.2.0 +version: 0.2.0.0 synopsis: Bindings to LZ4 description: This library is similar to the @lz4@ library except that it works @@ -17,6 +17,8 @@ build-type: Simple extra-source-files: cbits/lz4.h + cbits/lz4frame.h + cbits/xxhash.h cbits/lz4hc.h extra-doc-files: CHANGELOG.md @@ -41,12 +43,15 @@ , run-st >=0.1.1 && <0.2 hs-source-dirs: src - include-dirs: cbits - ghc-options: -O2 + include-dirs: cbits + ghc-options: -O2 -Wall + cc-options: -Wall c-sources: cbits/hs_lz4.c cbits/lz4.c + cbits/lz4frame.c cbits/lz4hc.c + cbits/xxhash.c test-suite test import: build-settings diff --git a/src/Lz4/Frame.hs b/src/Lz4/Frame.hs --- a/src/Lz4/Frame.hs +++ b/src/Lz4/Frame.hs @@ -1,4 +1,5 @@ {-# LANGUAGE BangPatterns #-} +{-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE BinaryLiterals #-} {-# LANGUAGE BlockArguments #-} {-# LANGUAGE DerivingStrategies #-} @@ -17,16 +18,22 @@ , decompressU ) where -import Lz4.Internal (requiredBufferSize,c_hs_compress_HC,c_hs_decompress_safe) +import Lz4.Internal (requiredBufferSize,c_hs_compress_HC,c_hs_decompress_safe,DecompressionContext) +import Lz4.Internal (c_LZ4F_createDecompressionContext, c_hs_decompress_frame) +import Lz4.Internal (c_LZ4F_freeDecompressionContext) +import Foreign.C.Types (CSize) +import Foreign.Ptr (Ptr) +import Foreign.Storable (peek) +import GHC.Exts (RealWorld) import Control.Monad (when) import Control.Monad.ST (runST) import Data.Bits ((.&.)) import Data.Bytes.Types (Bytes (Bytes)) import Data.Int (Int32) -import Data.Primitive (ByteArray (..), MutableByteArray (..)) +import Data.Primitive (ByteArray (..), MutableByteArray (..), MutablePrimArray) import Data.Word (Word8, Word32) -import GHC.IO (unsafeIOToST) +import GHC.IO (unsafeIOToST,unsafeDupablePerformIO) import qualified Data.Primitive as PM import qualified Data.Primitive.ByteArray.LittleEndian as LE @@ -39,18 +46,21 @@ -- It is difficult to find examples of lz4 frames that actually use -- any of these. Open a PR with an example of an lz4 frame that fails -- to decode if you find one. +-- +-- Error codes from the C library lz4 are returned in the Left data +-- constructor. decompressU :: Int -- ^ The exact size of the decompressed bytes -> Bytes -- ^ Compressed bytes - -> Maybe ByteArray + -> Either Int ByteArray decompressU !decompressedSize (Bytes arr@(ByteArray arr# ) off len) = do - when (len < 11) Nothing - when (indexWord8 arr off /= 0x04) Nothing - when (indexWord8 arr (off + 1) /= 0x22) Nothing - when (indexWord8 arr (off + 2) /= 0x4D) Nothing - when (indexWord8 arr (off + 3) /= 0x18) Nothing + when (len < 11) (Left 10000) + when (indexWord8 arr off /= 0x04) (Left 10001) + when (indexWord8 arr (off + 1) /= 0x22) (Left 10002) + when (indexWord8 arr (off + 2) /= 0x4D) (Left 10003) + when (indexWord8 arr (off + 3) /= 0x18) (Left 10004) let !flag = indexWord8 arr (off + 4) - when (flag /= 0b0110_0000) Nothing + -- when (flag /= 0b0110_0000) Nothing -- Here is the code that would read the size hint from the bd. However, -- there is no reason to use this since this function takes the actual -- size as an argument. We ignore the checksum at position off+6 as well. @@ -62,32 +72,50 @@ -- 0b0100_0000 -> pure 65536 -- _ -> Nothing -- when (maximumDecompressedSize < decompressedSize) Nothing - let !compressedSize = LE.indexUnalignedByteArray arr (off + 7) :: Word32 - let !compressedSizeI = fromIntegral (compressedSize .&. 0x7fff_ffff) :: Int - when (compressedSizeI + (4 + 3 + 4 + 4) /= len) Nothing - let !offPost = off + 11 + compressedSizeI - when (indexWord8 arr offPost /= 0x00) Nothing - when (indexWord8 arr (offPost + 1) /= 0x00) Nothing - when (indexWord8 arr (offPost + 2) /= 0x00) Nothing - when (indexWord8 arr (offPost + 3) /= 0x00) Nothing - case compressedSize .&. 0x8000_0000 of - 0 -> runST $ do - dst@(MutableByteArray dst# ) <- PM.newByteArray decompressedSize - actualSz <- unsafeIOToST (c_hs_decompress_safe arr# (off + 11) dst# 0 compressedSizeI decompressedSize) - -- Note: actualSz will be negative if decompression fails. That's fine. - if actualSz == decompressedSize - then do - dst' <- PM.unsafeFreezeByteArray dst - pure (Just dst') - else pure Nothing - _ -> do - -- When the upper bit of the size is set, it means that the data in - -- the block is uncompressed. This code path is not tested in the test - -- suite, and I cannot find examples of this feature used in the wild. - -- If anyone knows of an example, open a PR. - when (decompressedSize /= compressedSizeI) Nothing - when (decompressedSize + 15 /= len) Nothing - Just $! Bytes.toByteArrayClone (Bytes arr (off + 11) decompressedSize) + if | flag == 0b0110_0000 + , !compressedSize <- LE.indexUnalignedByteArray arr (off + 7) :: Word32 + , !compressedSizeI <- fromIntegral (compressedSize .&. 0x7fff_ffff) :: Int + , compressedSizeI + (4 + 3 + 4 + 4) == len -> do + -- When there is only one block and there aren't any checksums, + -- we can just decompress the single block and allocating and + -- freeing a context. This case is pretty common in practice. + let !offPost = off + 11 + compressedSizeI + when (indexWord8 arr offPost /= 0x00) (Left 10005) + when (indexWord8 arr (offPost + 1) /= 0x00) (Left 10006) + when (indexWord8 arr (offPost + 2) /= 0x00) (Left 10007) + when (indexWord8 arr (offPost + 3) /= 0x00) (Left 10008) + case compressedSize .&. 0x8000_0000 of + 0 -> runST $ do + dst@(MutableByteArray dst# ) <- PM.newByteArray decompressedSize + actualSz <- unsafeIOToST (c_hs_decompress_safe arr# (off + 11) dst# 0 compressedSizeI decompressedSize) + -- Note: actualSz will be negative if decompression fails. That's fine. + if actualSz == decompressedSize + then do + dst' <- PM.unsafeFreezeByteArray dst + pure (Right dst') + else pure (Left 10009) + _ -> do + -- When the upper bit of the size is set, it means that the data in + -- the block is uncompressed. This code path is not tested in the test + -- suite, and I cannot find examples of this feature used in the wild. + -- If anyone knows of an example, open a PR. + when (decompressedSize /= compressedSizeI) (Left 10010) + when (decompressedSize + 15 /= len) (Left 10011) + Right $! Bytes.toByteArrayClone (Bytes arr (off + 11) decompressedSize) + | otherwise -> unsafeDupablePerformIO $ do + dst@(MutableByteArray dst# ) <- PM.newByteArray decompressedSize + dctxPtrMba :: MutablePrimArray RealWorld (Ptr DecompressionContext) <- PM.newPinnedPrimArray 1 + let !dctxPtrPtr = PM.mutablePrimArrayContents dctxPtrMba + x <- c_LZ4F_createDecompressionContext dctxPtrPtr 100 + case x of + 0 -> do + dctxPtr <- peek dctxPtrPtr + r <- c_hs_decompress_frame dctxPtr arr# off len dst# decompressedSize + _ <- c_LZ4F_freeDecompressionContext dctxPtr + case r of + 0 -> Right <$> PM.unsafeFreezeByteArray dst + _ -> pure (Left r) + _ -> errorWithoutStackTrace "Lz4.Frame.decompressU: failed to create decompression context" {- | Use HC compression to produce a frame with a single block. All optional fields (checksums, content sizes, and dictionary IDs) @@ -105,8 +133,8 @@ -- | Bytes to compress Bytes -> ByteArray -compressHighlyU !lvl (Bytes (ByteArray arr) off len) = runST do - let maxSz = requiredBufferSize len + 15 +compressHighlyU !lvl (Bytes (ByteArray arr) off0 len0) = runST do + let maxSz = requiredBufferSize len0 + 15 dst@(MutableByteArray dst#) <- PM.newByteArray maxSz -- -- First 4 bytes: magic identifier PM.writeByteArray dst 0 (0x04 :: Word8) @@ -116,26 +144,35 @@ -- Next 3 bytes: frame descriptor PM.writeByteArray dst 4 (0b0110_0000 :: Word8) if - | len <= 65_536 -> do + | len0 <= 65_536 -> do PM.writeByteArray dst 5 (0b0100_0000 :: Word8) PM.writeByteArray dst 6 (0x82 :: Word8) - | len <= 262_144 -> do + | len0 <= 262_144 -> do PM.writeByteArray dst 5 (0b0101_0000 :: Word8) PM.writeByteArray dst 6 (0xFB :: Word8) - | len <= 1_048_576 -> do + | len0 <= 1_048_576 -> do PM.writeByteArray dst 5 (0b0110_0000 :: Word8) PM.writeByteArray dst 6 (0x51 :: Word8) | otherwise -> do PM.writeByteArray dst 5 (0b0111_0000 :: Word8) PM.writeByteArray dst 6 (0x73 :: Word8) - actualSz <- unsafeIOToST (c_hs_compress_HC arr off dst# 11 len maxSz lvl) - LE.writeUnalignedByteArray dst 7 (fromIntegral actualSz :: Int32) - PM.writeByteArray dst (actualSz + 11) (0x00 :: Word8) - PM.writeByteArray dst (actualSz + 12) (0x00 :: Word8) - PM.writeByteArray dst (actualSz + 13) (0x00 :: Word8) - PM.writeByteArray dst (actualSz + 14) (0x00 :: Word8) - PM.shrinkMutableByteArray dst (actualSz + 15) - PM.unsafeFreezeByteArray dst + let handleBlocks !ix !inputOff !inputRemaining = do + let !inputClipped = min inputRemaining 4_194_304 + actualSz <- unsafeIOToST (c_hs_compress_HC arr inputOff dst# (ix + 4) inputClipped maxSz lvl) + case actualSz of + 0 -> errorWithoutStackTrace "Lz4.Frame.compressHighlyU: compression failed" + _ -> do + LE.writeUnalignedByteArray dst ix (fromIntegral actualSz :: Int32) + let inputRemaining' = inputRemaining - inputClipped + let inputOff' = inputOff + inputClipped + if inputRemaining' > 0 + then do + handleBlocks (ix + 4 + actualSz) inputOff' inputRemaining' + else do + LE.writeUnalignedByteArray dst (actualSz + ix + 4) (0 :: Word32) + PM.shrinkMutableByteArray dst (actualSz + ix + 8) + PM.unsafeFreezeByteArray dst + handleBlocks 7 off0 len0 indexWord8 :: ByteArray -> Int -> Word8 {-# inline indexWord8 #-} diff --git a/src/Lz4/Internal.hs b/src/Lz4/Internal.hs --- a/src/Lz4/Internal.hs +++ b/src/Lz4/Internal.hs @@ -7,13 +7,20 @@ These functions do not perform any framing. -} module Lz4.Internal - ( requiredBufferSize + ( DecompressionContext + , requiredBufferSize , c_hs_compress_HC , c_hs_decompress_safe + , c_hs_decompress_frame + , c_LZ4F_createDecompressionContext + , c_LZ4F_freeDecompressionContext ) where -import GHC.Exts (ByteArray#, MutableByteArray#) +import GHC.Exts (ByteArray#, MutableByteArray#, Ptr) +import Foreign.C.Types (CUInt(..), CSize(..)) +-- | Phantom type for pointers +data DecompressionContext {- | Copied from the @LZ4_COMPRESSBOUND@ macro lz4.h to avoid using FFI for simple arithmetic. Make sure this stays in sync with the macro. @@ -42,3 +49,24 @@ -> Int -- Input size -> Int -- Destination capacity -> IO Int -- Result length + +foreign import ccall unsafe "hs_decompress_frame" + c_hs_decompress_frame :: + Ptr DecompressionContext + -> ByteArray# -- Source + -> Int -- Source offset + -> Int -- Source length + -> MutableByteArray# s -- Destination + -> Int -- Destination offset + -> IO Int -- Result (0 means success) + +foreign import ccall unsafe "LZ4F_createDecompressionContext" + c_LZ4F_createDecompressionContext :: + Ptr (Ptr DecompressionContext) + -> CUInt -- version + -> IO CSize + +foreign import ccall unsafe "LZ4F_freeDecompressionContext" + c_LZ4F_freeDecompressionContext :: + Ptr DecompressionContext + -> IO CSize diff --git a/test/Main.hs b/test/Main.hs --- a/test/Main.hs +++ b/test/Main.hs @@ -1,4 +1,5 @@ {-# LANGUAGE OverloadedStrings #-} +{-# LANGUAGE NumericUnderscores #-} {-# LANGUAGE ScopedTypeVariables #-} import Data.Bytes (Bytes) @@ -33,18 +34,50 @@ , testGroup "frame" [ testProperty "roundtrip-HC" $ forAll genByteArray $ \bs -> let cs = Frame.compressHighlyU 3 (Bytes.fromByteArray bs) in - Just bs + Right bs === Frame.decompressU (sizeofByteArray bs) (Bytes.fromByteArray cs) + , testCase "roundtrip-HC-80k" $ testRoundtrip 80_000 + , testCase "roundtrip-HC-800k" $ testRoundtrip 800_000 + , testCase "roundtrip-HC-2M" $ testRoundtrip 2_000_000 + , testCase "roundtrip-HC-5M" $ testRoundtrip 5_000_000 + , testCase "roundtrip-HC-9M" $ testRoundtrip 9_000_000 + , testCase "packing-HC-80k" $ testPacking 80_000 + , testCase "packing-HC-800k" $ testPacking 800_000 + , testCase "packing-HC-2M" $ testPacking 2_000_000 + , testCase "packing-HC-5M" $ testPacking 5_000_000 + , testCase "packing-HC-9M" $ testPacking 9_000_000 , testCase "example-a" $ case Frame.decompressU 20 (Bytes.fromByteArray exampleA) of - Nothing -> fail "decompression failed" - Just _ -> pure () + Left{} -> fail "decompression failed" + Right _ -> pure () , testCase "example-b" $ case Frame.decompressU 10 (Bytes.fromByteArray exampleB) of - Nothing -> fail "decompression failed" - Just x -> x @=? Exts.fromList [0xbb :: Word8, 0x01, 0xbb, 0x01, 0xbb, 0x01, 0xbb, 0x01, 0xbb, 0x01 ] + Left{} -> fail "decompression failed" + Right x -> x @=? Exts.fromList [0xbb :: Word8, 0x01, 0xbb, 0x01, 0xbb, 0x01, 0xbb, 0x01, 0xbb, 0x01 ] + , testCase "example-c" $ case Frame.decompressU 20 (Bytes.fromByteArray exampleC) of + Left e -> fail ("decompression failed, error code: " ++ show e) + Right _ -> pure () ] ] +testRoundtrip :: Int -> IO () +testRoundtrip sz = + let uncompressed = Bytes.replicate sz 0x01 in + let compressed = Frame.compressHighlyU 3 uncompressed in + case Frame.decompressU sz (Bytes.fromByteArray compressed) of + Left{} -> fail "decompression failed" + Right result -> if uncompressed == Bytes.fromByteArray result + then pure () + else fail "compression and decompression did not round trip" + +testPacking :: Int -> IO () +testPacking sz = + let uncompressed = Bytes.replicate sz 0x01 in + let compressed = Frame.compressHighlyU 3 uncompressed in + let lenCompressed = sizeofByteArray compressed in + if lenCompressed * 100 > sz + then fail "Repetition of same byte has compression factor less than 100" + else pure () + genBytes :: Gen Bytes genBytes = do n <- choose (0, 200) @@ -61,6 +94,19 @@ exampleA = Exts.fromList [ 0x04, 0x22, 0x4d, (0x18 :: Word8) , 0x60, 0x40, 0x82 + , 0x0d, 0x00, 0x00, 0x00 -- little-endian encoding of the number 13 + , 0x47, 0x15, 0x08, 0x01, 0x0a, 0x04 , 0x00, 0x50, 0x0a, 0x15, 0x08, 0x01, 0x0a + , 0x00, 0x00, 0x00, 0x00 + ] + +-- Same as exampleA, but the flag indicates that linked blocks are used. +-- There is only one block, so there aren't actually linked blocks, but +-- this lets us force the decompress function to take the slow path +-- where it sets up a decompression context. +exampleC :: ByteArray +exampleC = Exts.fromList + [ 0x04, 0x22, 0x4d, (0x18 :: Word8) + , 0x40, 0x40, 0xc0 , 0x0d, 0x00, 0x00, 0x00 -- little-endian encoding of the number 13 , 0x47, 0x15, 0x08, 0x01, 0x0a, 0x04 , 0x00, 0x50, 0x0a, 0x15, 0x08, 0x01, 0x0a , 0x00, 0x00, 0x00, 0x00