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Diffstat (limited to 'mfbt/lz4.h')
| -rw-r--r-- | mfbt/lz4.h | 531 |
1 files changed, 359 insertions, 172 deletions
diff --git a/mfbt/lz4.h b/mfbt/lz4.h index bf6780122..86ca0d59c 100644 --- a/mfbt/lz4.h +++ b/mfbt/lz4.h @@ -1,7 +1,8 @@ /* - LZ4 - Fast LZ compression algorithm - Header File - Copyright (C) 2011-2014, Yann Collet. + * LZ4 - Fast LZ compression algorithm + * Header File + * Copyright (C) 2011-2017, Yann Collet. + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) Redistribution and use in source and binary forms, with or without @@ -28,247 +29,433 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. You can contact the author at : - - LZ4 source repository : http://code.google.com/p/lz4/ - - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c + - LZ4 homepage : http://www.lz4.org + - LZ4 source repository : https://github.com/lz4/lz4 */ -#pragma once - #if defined (__cplusplus) extern "C" { #endif +#ifndef LZ4_H_2983827168210 +#define LZ4_H_2983827168210 -/************************************** - Version -**************************************/ -#define LZ4_VERSION_MAJOR 1 /* for major interface/format changes */ -#define LZ4_VERSION_MINOR 2 /* for minor interface/format changes */ +/* --- Dependency --- */ +#include <stddef.h> /* size_t */ + + +/** + Introduction + + LZ4 is lossless compression algorithm, providing compression speed at 400 MB/s per core, + scalable with multi-cores CPU. It features an extremely fast decoder, with speed in + multiple GB/s per core, typically reaching RAM speed limits on multi-core systems. + + The LZ4 compression library provides in-memory compression and decompression functions. + Compression can be done in: + - a single step (described as Simple Functions) + - a single step, reusing a context (described in Advanced Functions) + - unbounded multiple steps (described as Streaming compression) + + lz4.h provides block compression functions. It gives full buffer control to user. + Decompressing an lz4-compressed block also requires metadata (such as compressed size). + Each application is free to encode such metadata in whichever way it wants. + + An additional format, called LZ4 frame specification (doc/lz4_Frame_format.md), + take care of encoding standard metadata alongside LZ4-compressed blocks. + If your application requires interoperability, it's recommended to use it. + A library is provided to take care of it, see lz4frame.h. +*/ + +/*^*************************************************************** +* Export parameters +*****************************************************************/ +/* +* LZ4_DLL_EXPORT : +* Enable exporting of functions when building a Windows DLL +* LZ4LIB_API : +* Control library symbols visibility. +*/ +#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1) +# define LZ4LIB_API __declspec(dllexport) +#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1) +# define LZ4LIB_API __declspec(dllimport) /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ +#elif defined(__GNUC__) && (__GNUC__ >= 4) +# define LZ4LIB_API __attribute__ ((__visibility__ ("default"))) +#else +# define LZ4LIB_API +#endif + + +/*------ Version ------*/ +#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */ +#define LZ4_VERSION_MINOR 8 /* for new (non-breaking) interface capabilities */ #define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */ +#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE) -/************************************** - Tuning parameter +#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE +#define LZ4_QUOTE(str) #str +#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str) +#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) + +LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; to be used when checking dll version */ +LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; to be used when checking dll version */ + + +/*-************************************ +* Tuning parameter **************************************/ -/* +/*! * LZ4_MEMORY_USAGE : * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) * Increasing memory usage improves compression ratio * Reduced memory usage can improve speed, due to cache effect * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ -#define LZ4_MEMORY_USAGE 14 - +#ifndef LZ4_MEMORY_USAGE +# define LZ4_MEMORY_USAGE 14 +#endif -/************************************** - Simple Functions +/*-************************************ +* Simple Functions **************************************/ - -int LZ4_compress (const char* source, char* dest, int inputSize); -int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxOutputSize); - -/* -LZ4_compress() : - Compresses 'inputSize' bytes from 'source' into 'dest'. - Destination buffer must be already allocated, - and must be sized to handle worst cases situations (input data not compressible) - Worst case size evaluation is provided by function LZ4_compressBound() - inputSize : Max supported value is LZ4_MAX_INPUT_VALUE - return : the number of bytes written in buffer dest - or 0 if the compression fails - -LZ4_decompress_safe() : - compressedSize : is obviously the source size - maxOutputSize : is the size of the destination buffer, which must be already allocated. - return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) - If the destination buffer is not large enough, decoding will stop and output an error code (<0). +/*! LZ4_compress_default() : + Compresses 'sourceSize' bytes from buffer 'source' + into already allocated 'dest' buffer of size 'maxDestSize'. + Compression is guaranteed to succeed if 'maxDestSize' >= LZ4_compressBound(sourceSize). + It also runs faster, so it's a recommended setting. + If the function cannot compress 'source' into a more limited 'dest' budget, + compression stops *immediately*, and the function result is zero. + As a consequence, 'dest' content is not valid. + This function never writes outside 'dest' buffer, nor read outside 'source' buffer. + sourceSize : Max supported value is LZ4_MAX_INPUT_VALUE + maxDestSize : full or partial size of buffer 'dest' (which must be already allocated) + return : the number of bytes written into buffer 'dest' (necessarily <= maxOutputSize) + or 0 if compression fails */ +LZ4LIB_API int LZ4_compress_default(const char* source, char* dest, int sourceSize, int maxDestSize); + +/*! LZ4_decompress_safe() : + compressedSize : is the precise full size of the compressed block. + maxDecompressedSize : is the size of destination buffer, which must be already allocated. + return : the number of bytes decompressed into destination buffer (necessarily <= maxDecompressedSize) + If destination buffer is not large enough, decoding will stop and output an error code (<0). If the source stream is detected malformed, the function will stop decoding and return a negative result. - This function is protected against buffer overflow exploits : - it never writes outside of output buffer, and never reads outside of input buffer. - Therefore, it is protected against malicious data packets. -*/ - - -/* -Note : - Should you prefer to explicitly allocate compression-table memory using your own allocation method, - use the streaming functions provided below, simply reset the memory area between each call to LZ4_compress_continue() + This function is protected against buffer overflow exploits, including malicious data packets. + It never writes outside output buffer, nor reads outside input buffer. */ +LZ4LIB_API int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxDecompressedSize); -/************************************** - Advanced Functions +/*-************************************ +* Advanced Functions **************************************/ #define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */ -#define LZ4_COMPRESSBOUND(isize) ((unsigned int)(isize) > (unsigned int)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16) +#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16) -/* +/*! LZ4_compressBound() : - Provides the maximum size that LZ4 may output in a "worst case" scenario (input data not compressible) - primarily useful for memory allocation of output buffer. - macro is also provided when result needs to be evaluated at compilation (such as stack memory allocation). - - isize : is the input size. Max supported value is LZ4_MAX_INPUT_SIZE - return : maximum output size in a "worst case" scenario - or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE) + Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible) + This function is primarily useful for memory allocation purposes (destination buffer size). + Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example). + Note that LZ4_compress_default() compress faster when dest buffer size is >= LZ4_compressBound(srcSize) + inputSize : max supported value is LZ4_MAX_INPUT_SIZE + return : maximum output size in a "worst case" scenario + or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE) +*/ +LZ4LIB_API int LZ4_compressBound(int inputSize); + +/*! +LZ4_compress_fast() : + Same as LZ4_compress_default(), but allows to select an "acceleration" factor. + The larger the acceleration value, the faster the algorithm, but also the lesser the compression. + It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed. + An acceleration value of "1" is the same as regular LZ4_compress_default() + Values <= 0 will be replaced by ACCELERATION_DEFAULT (see lz4.c), which is 1. */ -int LZ4_compressBound(int isize); +LZ4LIB_API int LZ4_compress_fast (const char* source, char* dest, int sourceSize, int maxDestSize, int acceleration); -/* -LZ4_compress_limitedOutput() : - Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'. - If it cannot achieve it, compression will stop, and result of the function will be zero. - This function never writes outside of provided output buffer. - - inputSize : Max supported value is LZ4_MAX_INPUT_VALUE - maxOutputSize : is the size of the destination buffer (which must be already allocated) - return : the number of bytes written in buffer 'dest' - or 0 if the compression fails +/*! +LZ4_compress_fast_extState() : + Same compression function, just using an externally allocated memory space to store compression state. + Use LZ4_sizeofState() to know how much memory must be allocated, + and allocate it on 8-bytes boundaries (using malloc() typically). + Then, provide it as 'void* state' to compression function. +*/ +LZ4LIB_API int LZ4_sizeofState(void); +LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* source, char* dest, int inputSize, int maxDestSize, int acceleration); + + +/*! +LZ4_compress_destSize() : + Reverse the logic, by compressing as much data as possible from 'source' buffer + into already allocated buffer 'dest' of size 'targetDestSize'. + This function either compresses the entire 'source' content into 'dest' if it's large enough, + or fill 'dest' buffer completely with as much data as possible from 'source'. + *sourceSizePtr : will be modified to indicate how many bytes where read from 'source' to fill 'dest'. + New value is necessarily <= old value. + return : Nb bytes written into 'dest' (necessarily <= targetDestSize) + or 0 if compression fails */ -int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize); +LZ4LIB_API int LZ4_compress_destSize (const char* source, char* dest, int* sourceSizePtr, int targetDestSize); -/* +/*! LZ4_decompress_fast() : originalSize : is the original and therefore uncompressed size return : the number of bytes read from the source buffer (in other words, the compressed size) - If the source stream is malformed, the function will stop decoding and return a negative result. + If the source stream is detected malformed, the function will stop decoding and return a negative result. Destination buffer must be already allocated. Its size must be a minimum of 'originalSize' bytes. - note : This function is a bit faster than LZ4_decompress_safe() - It provides fast decompression and fully respect memory boundaries for properly formed compressed data. - It does not provide full protection against intentionnally modified data stream. - Use this function in a trusted environment (data to decode comes from a trusted source). + note : This function fully respect memory boundaries for properly formed compressed data. + It is a bit faster than LZ4_decompress_safe(). + However, it does not provide any protection against intentionally modified data stream (malicious input). + Use this function in trusted environment only (data to decode comes from a trusted source). */ -int LZ4_decompress_fast (const char* source, char* dest, int originalSize); +LZ4LIB_API int LZ4_decompress_fast (const char* source, char* dest, int originalSize); - -/* +/*! LZ4_decompress_safe_partial() : This function decompress a compressed block of size 'compressedSize' at position 'source' - into output buffer 'dest' of size 'maxOutputSize'. + into destination buffer 'dest' of size 'maxDecompressedSize'. The function tries to stop decompressing operation as soon as 'targetOutputSize' has been reached, reducing decompression time. - return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) + return : the number of bytes decoded in the destination buffer (necessarily <= maxDecompressedSize) Note : this number can be < 'targetOutputSize' should the compressed block to decode be smaller. Always control how many bytes were decoded. If the source stream is detected malformed, the function will stop decoding and return a negative result. This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets */ -int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxOutputSize); +LZ4LIB_API int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize); -/*********************************************** - Experimental Streaming Compression Functions +/*-********************************************* +* Streaming Compression Functions ***********************************************/ +typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */ -#define LZ4_STREAMSIZE_U32 ((1 << (LZ4_MEMORY_USAGE-2)) + 8) -#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U32 * sizeof(unsigned int)) -/* - * LZ4_stream_t - * information structure to track an LZ4 stream. - * important : set this structure content to zero before first use ! - */ -typedef struct { unsigned int table[LZ4_STREAMSIZE_U32]; } LZ4_stream_t; - -/* - * If you prefer dynamic allocation methods, - * LZ4_createStream - * provides a pointer (void*) towards an initialized LZ4_stream_t structure. - * LZ4_free just frees it. +/*! LZ4_createStream() and LZ4_freeStream() : + * LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure. + * LZ4_freeStream() releases its memory. */ -void* LZ4_createStream(); -int LZ4_free (void* LZ4_stream); - +LZ4LIB_API LZ4_stream_t* LZ4_createStream(void); +LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr); -/* - * LZ4_loadDict - * Use this function to load a static dictionary into LZ4_stream. - * Any previous data will be forgotten, only 'dictionary' will remain in memory. - * Loading a size of 0 is allowed (same effect as init). - * Return : 1 if OK, 0 if error +/*! LZ4_resetStream() : + * An LZ4_stream_t structure can be allocated once and re-used multiple times. + * Use this function to init an allocated `LZ4_stream_t` structure and start a new compression. */ -int LZ4_loadDict (void* LZ4_stream, const char* dictionary, int dictSize); +LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr); -/* - * LZ4_compress_continue - * Compress data block 'source', using blocks compressed before as dictionary to improve compression ratio - * Previous data blocks are assumed to still be present at their previous location. +/*! LZ4_loadDict() : + * Use this function to load a static dictionary into LZ4_stream. + * Any previous data will be forgotten, only 'dictionary' will remain in memory. + * Loading a size of 0 is allowed. + * Return : dictionary size, in bytes (necessarily <= 64 KB) */ -int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize); - -/* - * LZ4_compress_limitedOutput_continue - * Same as before, but also specify a maximum target compressed size (maxOutputSize) - * If objective cannot be met, compression exits, and returns a zero. +LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize); + +/*! LZ4_compress_fast_continue() : + * Compress buffer content 'src', using data from previously compressed blocks as dictionary to improve compression ratio. + * Important : Previous data blocks are assumed to remain present and unmodified ! + * 'dst' buffer must be already allocated. + * If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster. + * If not, and if compressed data cannot fit into 'dst' buffer size, compression stops, and function @return==0. + * After an error, the stream status is invalid, it can only be reset or freed. */ -int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize); +LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); -/* - * LZ4_saveDict - * If previously compressed data block is not guaranteed to remain at its previous memory location - * save it into a safe place (char* safeBuffer) - * Note : you don't need to call LZ4_loadDict() afterwards, - * dictionary is immediately usable, you can therefore call again LZ4_compress_continue() - * Return : 1 if OK, 0 if error - * Note : any dictSize > 64 KB will be interpreted as 64KB. +/*! LZ4_saveDict() : + * If previously compressed data block is not guaranteed to remain available at its current memory location, + * save it into a safer place (char* safeBuffer). + * Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable. + * @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. */ -int LZ4_saveDict (void* LZ4_stream, char* safeBuffer, int dictSize); +LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize); -/************************************************ - Experimental Streaming Decompression Functions +/*-********************************************** +* Streaming Decompression Functions +* Bufferless synchronous API ************************************************/ +typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* incomplete type (defined later) */ -#define LZ4_STREAMDECODESIZE_U32 4 -#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U32 * sizeof(unsigned int)) -/* - * LZ4_streamDecode_t - * information structure to track an LZ4 stream. - * important : set this structure content to zero before first use ! +/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() : + * creation / destruction of streaming decompression tracking structure */ +LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void); +LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream); + +/*! LZ4_setStreamDecode() : + * Use this function to instruct where to find the dictionary. + * Setting a size of 0 is allowed (same effect as reset). + * @return : 1 if OK, 0 if error */ -typedef struct { unsigned int table[LZ4_STREAMDECODESIZE_U32]; } LZ4_streamDecode_t; +LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize); + +/*! LZ4_decompress_*_continue() : + * These decoding functions allow decompression of multiple blocks in "streaming" mode. + * Previously decoded blocks *must* remain available at the memory position where they were decoded (up to 64 KB) + * In the case of a ring buffers, decoding buffer must be either : + * - Exactly same size as encoding buffer, with same update rule (block boundaries at same positions) + * In which case, the decoding & encoding ring buffer can have any size, including very small ones ( < 64 KB). + * - Larger than encoding buffer, by a minimum of maxBlockSize more bytes. + * maxBlockSize is implementation dependent. It's the maximum size you intend to compress into a single block. + * In which case, encoding and decoding buffers do not need to be synchronized, + * and encoding ring buffer can have any size, including small ones ( < 64 KB). + * - _At least_ 64 KB + 8 bytes + maxBlockSize. + * In which case, encoding and decoding buffers do not need to be synchronized, + * and encoding ring buffer can have any size, including larger than decoding buffer. + * Whenever these conditions are not possible, save the last 64KB of decoded data into a safe buffer, + * and indicate where it is saved using LZ4_setStreamDecode() +*/ +LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxDecompressedSize); +LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize); -/* - * If you prefer dynamic allocation methods, - * LZ4_createStreamDecode() - * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure. - * LZ4_free just frees it. + +/*! LZ4_decompress_*_usingDict() : + * These decoding functions work the same as + * a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue() + * They are stand-alone, and don't need an LZ4_streamDecode_t structure. */ -void* LZ4_createStreamDecode(); -int LZ4_free (void* LZ4_stream); /* yes, it's the same one as for compression */ +LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxDecompressedSize, const char* dictStart, int dictSize); +LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize); + + +/*^********************************************** + * !!!!!! STATIC LINKING ONLY !!!!!! + ***********************************************/ +/*-************************************ + * Private definitions + ************************************** + * Do not use these definitions. + * They are exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`. + * Using these definitions will expose code to API and/or ABI break in future versions of the library. + **************************************/ +#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2) +#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE) +#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */ + +#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +#include <stdint.h> + +typedef struct { + uint32_t hashTable[LZ4_HASH_SIZE_U32]; + uint32_t currentOffset; + uint32_t initCheck; + const uint8_t* dictionary; + uint8_t* bufferStart; /* obsolete, used for slideInputBuffer */ + uint32_t dictSize; +} LZ4_stream_t_internal; + +typedef struct { + const uint8_t* externalDict; + size_t extDictSize; + const uint8_t* prefixEnd; + size_t prefixSize; +} LZ4_streamDecode_t_internal; + +#else + +typedef struct { + unsigned int hashTable[LZ4_HASH_SIZE_U32]; + unsigned int currentOffset; + unsigned int initCheck; + const unsigned char* dictionary; + unsigned char* bufferStart; /* obsolete, used for slideInputBuffer */ + unsigned int dictSize; +} LZ4_stream_t_internal; + +typedef struct { + const unsigned char* externalDict; + size_t extDictSize; + const unsigned char* prefixEnd; + size_t prefixSize; +} LZ4_streamDecode_t_internal; -/* -*_continue() : - These decoding functions allow decompression of multiple blocks in "streaming" mode. - Previously decoded blocks must still be available at the memory position where they were decoded. - If it's not possible, save the relevant part of decoded data into a safe buffer, - and indicate where it stands using LZ4_setDictDecode() -*/ -int LZ4_decompress_safe_continue (void* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize); -int LZ4_decompress_fast_continue (void* LZ4_streamDecode, const char* source, char* dest, int originalSize); +#endif -/* - * LZ4_setDictDecode - * Use this function to instruct where to find the dictionary. - * This function can be used to specify a static dictionary, - * or to instruct where to find some previously decoded data saved into a different memory space. - * Setting a size of 0 is allowed (same effect as no dictionary). - * Return : 1 if OK, 0 if error +/*! + * LZ4_stream_t : + * information structure to track an LZ4 stream. + * init this structure before first use. + * note : only use in association with static linking ! + * this definition is not API/ABI safe, + * it may change in a future version ! */ -int LZ4_setDictDecode (void* LZ4_streamDecode, const char* dictionary, int dictSize); +#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4) +#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long)) +union LZ4_stream_u { + unsigned long long table[LZ4_STREAMSIZE_U64]; + LZ4_stream_t_internal internal_donotuse; +} ; /* previously typedef'd to LZ4_stream_t */ + + +/*! + * LZ4_streamDecode_t : + * information structure to track an LZ4 stream during decompression. + * init this structure using LZ4_setStreamDecode (or memset()) before first use + * note : only use in association with static linking ! + * this definition is not API/ABI safe, + * and may change in a future version ! + */ +#define LZ4_STREAMDECODESIZE_U64 4 +#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long)) +union LZ4_streamDecode_u { + unsigned long long table[LZ4_STREAMDECODESIZE_U64]; + LZ4_streamDecode_t_internal internal_donotuse; +} ; /* previously typedef'd to LZ4_streamDecode_t */ -/* -Advanced decoding functions : -*_usingDict() : - These decoding functions work the same as - a combination of LZ4_setDictDecode() followed by LZ4_decompress_x_continue() - all together into a single function call. - It doesn't use nor update an LZ4_streamDecode_t structure. -*/ -int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize); -int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize); +/*-************************************ +* Obsolete Functions +**************************************/ +/*! Deprecation warnings + Should deprecation warnings be a problem, + it is generally possible to disable them, + typically with -Wno-deprecated-declarations for gcc + or _CRT_SECURE_NO_WARNINGS in Visual. + Otherwise, it's also possible to define LZ4_DISABLE_DEPRECATE_WARNINGS */ +#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS +# define LZ4_DEPRECATED(message) /* disable deprecation warnings */ +#else +# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) +# if defined (__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)) +# else +# pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler") +# define LZ4_DEPRECATED(message) +# endif +#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */ + +/* Obsolete compression functions */ +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress (const char* source, char* dest, int sourceSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_default() instead") int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize); + +/* Obsolete decompression functions */ +LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast() instead") int LZ4_uncompress (const char* source, char* dest, int outputSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe() instead") int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize); + +/* Obsolete streaming functions; use new streaming interface whenever possible */ +LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") void* LZ4_create (char* inputBuffer); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_createStream() instead") int LZ4_sizeofStreamState(void); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_resetStream() instead") int LZ4_resetStreamState(void* state, char* inputBuffer); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_saveDict() instead") char* LZ4_slideInputBuffer (void* state); + +/* Obsolete streaming decoding functions */ +LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize); +LZ4LIB_API LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize); + +#endif /* LZ4_H_2983827168210 */ #if defined (__cplusplus) |