mirror of https://github.com/borgbackup/borg.git
Merge pull request #5001 from ThomasWaldmann/upgrade-lz4-master
upgrade bundled lz4 to 1.9.2
This commit is contained in:
TW
GitHub
commit
108c590c02
File diff suppressed because it is too large
Load Diff
|
|
@ -46,24 +46,31 @@ extern "C" {
|
|||
/**
|
||||
Introduction
|
||||
|
||||
LZ4 is lossless compression algorithm, providing compression speed at 500 MB/s per core,
|
||||
LZ4 is lossless compression algorithm, providing compression speed >500 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.
|
||||
It gives full buffer control to user.
|
||||
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.
|
||||
lz4.h generates and decodes LZ4-compressed blocks (doc/lz4_Block_format.md).
|
||||
Decompressing such a compressed block requires additional metadata.
|
||||
Exact metadata depends on exact decompression function.
|
||||
For the typical case of LZ4_decompress_safe(),
|
||||
metadata includes block's compressed size, and maximum bound of decompressed size.
|
||||
Each application is free to encode and pass 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.
|
||||
Frame format is required for interoperability.
|
||||
It is delivered through a companion API, declared in lz4frame.h.
|
||||
lz4.h only handle blocks, it can not generate Frames.
|
||||
|
||||
Blocks are different from Frames (doc/lz4_Frame_format.md).
|
||||
Frames bundle both blocks and metadata in a specified manner.
|
||||
Embedding metadata is required for compressed data to be self-contained and portable.
|
||||
Frame format is delivered through a companion API, declared in lz4frame.h.
|
||||
The `lz4` CLI can only manage frames.
|
||||
*/
|
||||
|
||||
/*^***************************************************************
|
||||
|
|
@ -92,8 +99,8 @@ extern "C" {
|
|||
|
||||
/*------ 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 3 /* for tweaks, bug-fixes, or development */
|
||||
#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_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
|
||||
|
||||
|
|
@ -103,7 +110,7 @@ extern "C" {
|
|||
#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)
|
||||
|
||||
LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version */
|
||||
LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; unseful to check dll version */
|
||||
LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version */
|
||||
|
||||
|
||||
/*-************************************
|
||||
|
|
@ -112,40 +119,48 @@ LZ4LIB_API const char* LZ4_versionString (void); /**< library version string;
|
|||
/*!
|
||||
* 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 cache effect
|
||||
* Increasing memory usage improves compression ratio.
|
||||
* Reduced memory usage may improve speed, 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
|
||||
#endif
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Simple Functions
|
||||
**************************************/
|
||||
/*! LZ4_compress_default() :
|
||||
Compresses 'srcSize' bytes from buffer 'src'
|
||||
into already allocated 'dst' buffer of size 'dstCapacity'.
|
||||
Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
|
||||
It also runs faster, so it's a recommended setting.
|
||||
If the function cannot compress 'src' into a more limited 'dst' budget,
|
||||
compression stops *immediately*, and the function result is zero.
|
||||
Note : as a consequence, 'dst' content is not valid.
|
||||
Note 2 : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
|
||||
srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
|
||||
dstCapacity : size of buffer 'dst' (which must be already allocated)
|
||||
return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
|
||||
or 0 if compression fails */
|
||||
* Compresses 'srcSize' bytes from buffer 'src'
|
||||
* into already allocated 'dst' buffer of size 'dstCapacity'.
|
||||
* Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
|
||||
* It also runs faster, so it's a recommended setting.
|
||||
* If the function cannot compress 'src' into a more limited 'dst' budget,
|
||||
* compression stops *immediately*, and the function result is zero.
|
||||
* In which case, 'dst' content is undefined (invalid).
|
||||
* srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
|
||||
* dstCapacity : size of buffer 'dst' (which must be already allocated)
|
||||
* @return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
|
||||
* or 0 if compression fails
|
||||
* Note : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
|
||||
|
||||
/*! LZ4_decompress_safe() :
|
||||
compressedSize : is the exact complete size of the compressed block.
|
||||
dstCapacity : is the size of destination buffer, which must be already allocated.
|
||||
return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
|
||||
If destination buffer is not large enough, decoding will stop and output an error code (negative value).
|
||||
If the source stream is detected malformed, the function will stop decoding and return a negative result.
|
||||
This function is protected against malicious data packets.
|
||||
*/
|
||||
* compressedSize : is the exact complete size of the compressed block.
|
||||
* dstCapacity : is the size of destination buffer (which must be already allocated), presumed an upper bound of decompressed size.
|
||||
* @return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
|
||||
* If destination buffer is not large enough, decoding will stop and output an error code (negative value).
|
||||
* If the source stream is detected malformed, the function will stop decoding and return a negative result.
|
||||
* Note 1 : This function is protected against malicious data packets :
|
||||
* it will never writes outside 'dst' buffer, nor read outside 'source' buffer,
|
||||
* even if the compressed block is maliciously modified to order the decoder to do these actions.
|
||||
* In such case, the decoder stops immediately, and considers the compressed block malformed.
|
||||
* Note 2 : compressedSize and dstCapacity must be provided to the function, the compressed block does not contain them.
|
||||
* The implementation is free to send / store / derive this information in whichever way is most beneficial.
|
||||
* If there is a need for a different format which bundles together both compressed data and its metadata, consider looking at lz4frame.h instead.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);
|
||||
|
||||
|
||||
|
|
@ -155,8 +170,7 @@ LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSi
|
|||
#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
|
||||
#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
|
||||
|
||||
/*!
|
||||
LZ4_compressBound() :
|
||||
/*! LZ4_compressBound() :
|
||||
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).
|
||||
|
|
@ -167,8 +181,7 @@ LZ4_compressBound() :
|
|||
*/
|
||||
LZ4LIB_API int LZ4_compressBound(int inputSize);
|
||||
|
||||
/*!
|
||||
LZ4_compress_fast() :
|
||||
/*! LZ4_compress_fast() :
|
||||
Same as LZ4_compress_default(), but allows selection of "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.
|
||||
|
|
@ -178,13 +191,12 @@ LZ4_compress_fast() :
|
|||
LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
|
||||
/*!
|
||||
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 this buffer as 'void* state' to compression function.
|
||||
*/
|
||||
/*! LZ4_compress_fast_extState() :
|
||||
* Same as LZ4_compress_fast(), using an externally allocated memory space for its state.
|
||||
* Use LZ4_sizeofState() to know how much memory must be allocated,
|
||||
* and allocate it on 8-bytes boundaries (using `malloc()` typically).
|
||||
* Then, provide this buffer as `void* state` to compression function.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_sizeofState(void);
|
||||
LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
|
|
@ -204,27 +216,6 @@ LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* d
|
|||
LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize);
|
||||
|
||||
|
||||
/*! LZ4_decompress_fast() : **unsafe!**
|
||||
* This function used to be a bit faster than LZ4_decompress_safe(),
|
||||
* though situation has changed in recent versions,
|
||||
* and now `LZ4_decompress_safe()` can be as fast and sometimes faster than `LZ4_decompress_fast()`.
|
||||
* Moreover, LZ4_decompress_fast() is not protected vs malformed input, as it doesn't perform full validation of compressed data.
|
||||
* As a consequence, this function is no longer recommended, and may be deprecated in future versions.
|
||||
* It's only remaining specificity is that it can decompress data without knowing its compressed size.
|
||||
*
|
||||
* originalSize : is the uncompressed size to regenerate.
|
||||
* `dst` must be already allocated, its size must be >= 'originalSize' bytes.
|
||||
* @return : number of bytes read from source buffer (== compressed size).
|
||||
* If the source stream is detected malformed, the function stops decoding and returns a negative result.
|
||||
* note : This function requires uncompressed originalSize to be known in advance.
|
||||
* The function never writes past the output buffer.
|
||||
* However, since it doesn't know its 'src' size, it may read past the intended input.
|
||||
* Also, because match offsets are not validated during decoding,
|
||||
* reads from 'src' may underflow.
|
||||
* Use this function in trusted environment **only**.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
|
||||
|
||||
/*! LZ4_decompress_safe_partial() :
|
||||
* Decompress an LZ4 compressed block, of size 'srcSize' at position 'src',
|
||||
* into destination buffer 'dst' of size 'dstCapacity'.
|
||||
|
|
@ -257,30 +248,49 @@ LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcS
|
|||
***********************************************/
|
||||
typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
|
||||
|
||||
/*! LZ4_createStream() and LZ4_freeStream() :
|
||||
* LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
|
||||
* LZ4_freeStream() releases its memory.
|
||||
*/
|
||||
LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
|
||||
LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr);
|
||||
|
||||
/*! LZ4_resetStream() :
|
||||
* An LZ4_stream_t structure can be allocated once and re-used multiple times.
|
||||
* Use this function to start compressing a new stream.
|
||||
/*! LZ4_resetStream_fast() : v1.9.0+
|
||||
* Use this to prepare an LZ4_stream_t for a new chain of dependent blocks
|
||||
* (e.g., LZ4_compress_fast_continue()).
|
||||
*
|
||||
* An LZ4_stream_t must be initialized once before usage.
|
||||
* This is automatically done when created by LZ4_createStream().
|
||||
* However, should the LZ4_stream_t be simply declared on stack (for example),
|
||||
* it's necessary to initialize it first, using LZ4_initStream().
|
||||
*
|
||||
* After init, start any new stream with LZ4_resetStream_fast().
|
||||
* A same LZ4_stream_t can be re-used multiple times consecutively
|
||||
* and compress multiple streams,
|
||||
* provided that it starts each new stream with LZ4_resetStream_fast().
|
||||
*
|
||||
* LZ4_resetStream_fast() is much faster than LZ4_initStream(),
|
||||
* but is not compatible with memory regions containing garbage data.
|
||||
*
|
||||
* Note: it's only useful to call LZ4_resetStream_fast()
|
||||
* in the context of streaming compression.
|
||||
* The *extState* functions perform their own resets.
|
||||
* Invoking LZ4_resetStream_fast() before is redundant, and even counterproductive.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
|
||||
LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
|
||||
|
||||
/*! LZ4_loadDict() :
|
||||
* Use this function to load a static dictionary into LZ4_stream_t.
|
||||
* Any previous data will be forgotten, only 'dictionary' will remain in memory.
|
||||
* Use this function to reference a static dictionary into LZ4_stream_t.
|
||||
* The dictionary must remain available during compression.
|
||||
* LZ4_loadDict() triggers a reset, so any previous data will be forgotten.
|
||||
* The same dictionary will have to be loaded on decompression side for successful decoding.
|
||||
* Dictionary are useful for better compression of small data (KB range).
|
||||
* While LZ4 accept any input as dictionary,
|
||||
* results are generally better when using Zstandard's Dictionary Builder.
|
||||
* Loading a size of 0 is allowed, and is the same as reset.
|
||||
* @return : dictionary size, in bytes (necessarily <= 64 KB)
|
||||
* @return : loaded dictionary size, in bytes (necessarily <= 64 KB)
|
||||
*/
|
||||
LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
|
||||
|
||||
/*! LZ4_compress_fast_continue() :
|
||||
* Compress 'src' content using data from previously compressed blocks, for better compression ratio.
|
||||
* 'dst' buffer must be already allocated.
|
||||
* 'dst' buffer must be already allocated.
|
||||
* If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
|
||||
*
|
||||
* @return : size of compressed block
|
||||
|
|
@ -288,10 +298,10 @@ LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, in
|
|||
*
|
||||
* Note 1 : Each invocation to LZ4_compress_fast_continue() generates a new block.
|
||||
* Each block has precise boundaries.
|
||||
* Each block must be decompressed separately, calling LZ4_decompress_*() with relevant metadata.
|
||||
* It's not possible to append blocks together and expect a single invocation of LZ4_decompress_*() to decompress them together.
|
||||
* Each block must be decompressed separately, calling LZ4_decompress_*() with associated metadata.
|
||||
*
|
||||
* Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory!
|
||||
* Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory !
|
||||
*
|
||||
* Note 3 : When input is structured as a double-buffer, each buffer can have any size, including < 64 KB.
|
||||
* Make sure that buffers are separated, by at least one byte.
|
||||
|
|
@ -299,7 +309,7 @@ LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, in
|
|||
*
|
||||
* Note 4 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
|
||||
*
|
||||
* Note 5 : After an error, the stream status is invalid, it can only be reset or freed.
|
||||
* Note 5 : After an error, the stream status is undefined (invalid), it can only be reset or freed.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
|
|
@ -335,7 +345,7 @@ LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_str
|
|||
*/
|
||||
LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
|
||||
|
||||
/*! LZ4_decoderRingBufferSize() : v1.8.2
|
||||
/*! LZ4_decoderRingBufferSize() : v1.8.2+
|
||||
* Note : in a ring buffer scenario (optional),
|
||||
* blocks are presumed decompressed next to each other
|
||||
* up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
|
||||
|
|
@ -347,7 +357,7 @@ LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const
|
|||
* or 0 if there is an error (invalid maxBlockSize).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
|
||||
#define LZ4_DECODER_RING_BUFFER_SIZE(mbs) (65536 + 14 + (mbs)) /* for static allocation; mbs presumed valid */
|
||||
#define LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize) (65536 + 14 + (maxBlockSize)) /* for static allocation; maxBlockSize presumed valid */
|
||||
|
||||
/*! LZ4_decompress_*_continue() :
|
||||
* These decoding functions allow decompression of consecutive blocks in "streaming" mode.
|
||||
|
|
@ -375,83 +385,72 @@ LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
|
|||
* 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_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
|
||||
|
||||
|
||||
/*! 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.
|
||||
* Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
|
||||
* Dictionary is presumed stable : it must remain accessible and unmodified during decompression.
|
||||
* 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_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
|
||||
|
||||
#endif /* LZ4_H_2983827168210 */
|
||||
|
||||
|
||||
/*^**********************************************
|
||||
/*^*************************************
|
||||
* !!!!!! STATIC LINKING ONLY !!!!!!
|
||||
***********************************************/
|
||||
***************************************/
|
||||
|
||||
/*-************************************
|
||||
* Unstable declarations
|
||||
**************************************
|
||||
* Declarations in this section should be considered unstable.
|
||||
* Use at your own peril, etc., etc.
|
||||
* They may be removed in the future.
|
||||
* Their signatures may change.
|
||||
**************************************/
|
||||
/*-****************************************************************************
|
||||
* Experimental section
|
||||
*
|
||||
* Symbols declared in this section must be considered unstable. Their
|
||||
* signatures or semantics may change, or they may be removed altogether in the
|
||||
* future. They are therefore only safe to depend on when the caller is
|
||||
* statically linked against the library.
|
||||
*
|
||||
* To protect against unsafe usage, not only are the declarations guarded,
|
||||
* the definitions are hidden by default
|
||||
* when building LZ4 as a shared/dynamic library.
|
||||
*
|
||||
* In order to access these declarations,
|
||||
* define LZ4_STATIC_LINKING_ONLY in your application
|
||||
* before including LZ4's headers.
|
||||
*
|
||||
* In order to make their implementations accessible dynamically, you must
|
||||
* define LZ4_PUBLISH_STATIC_FUNCTIONS when building the LZ4 library.
|
||||
******************************************************************************/
|
||||
|
||||
#ifdef LZ4_STATIC_LINKING_ONLY
|
||||
|
||||
/*! LZ4_resetStream_fast() :
|
||||
* Use this, like LZ4_resetStream(), to prepare a context for a new chain of
|
||||
* calls to a streaming API (e.g., LZ4_compress_fast_continue()).
|
||||
*
|
||||
* Note:
|
||||
* Using this in advance of a non- streaming-compression function is redundant,
|
||||
* and potentially bad for performance, since they all perform their own custom
|
||||
* reset internally.
|
||||
*
|
||||
* Differences from LZ4_resetStream():
|
||||
* When an LZ4_stream_t is known to be in a internally coherent state,
|
||||
* it can often be prepared for a new compression with almost no work, only
|
||||
* sometimes falling back to the full, expensive reset that is always required
|
||||
* when the stream is in an indeterminate state (i.e., the reset performed by
|
||||
* LZ4_resetStream()).
|
||||
*
|
||||
* LZ4_streams are guaranteed to be in a valid state when:
|
||||
* - returned from LZ4_createStream()
|
||||
* - reset by LZ4_resetStream()
|
||||
* - memset(stream, 0, sizeof(LZ4_stream_t)), though this is discouraged
|
||||
* - the stream was in a valid state and was reset by LZ4_resetStream_fast()
|
||||
* - the stream was in a valid state and was then used in any compression call
|
||||
* that returned success
|
||||
* - the stream was in an indeterminate state and was used in a compression
|
||||
* call that fully reset the state (e.g., LZ4_compress_fast_extState()) and
|
||||
* that returned success
|
||||
*
|
||||
* When a stream isn't known to be in a valid state, it is not safe to pass to
|
||||
* any fastReset or streaming function. It must first be cleansed by the full
|
||||
* LZ4_resetStream().
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
|
||||
#ifndef LZ4_STATIC_3504398509
|
||||
#define LZ4_STATIC_3504398509
|
||||
|
||||
#ifdef LZ4_PUBLISH_STATIC_FUNCTIONS
|
||||
#define LZ4LIB_STATIC_API LZ4LIB_API
|
||||
#else
|
||||
#define LZ4LIB_STATIC_API
|
||||
#endif
|
||||
|
||||
|
||||
/*! 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 above comment on LZ4_resetStream_fast() for a definition of "correctly
|
||||
* initialized"). From a high level, the difference is that this function
|
||||
* initializes the provided state with a call to something like
|
||||
* LZ4_resetStream_fast() while LZ4_compress_fast_extState() starts with a
|
||||
* call to LZ4_resetStream().
|
||||
* 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 above comment on LZ4_resetStream_fast() for a definition of "correctly initialized").
|
||||
* From a high level, the difference is that
|
||||
* this function initializes the provided state with a call to something like LZ4_resetStream_fast()
|
||||
* while LZ4_compress_fast_extState() starts with a call to LZ4_resetStream().
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
LZ4LIB_STATIC_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
/*! LZ4_attach_dictionary() :
|
||||
* This is an experimental API that allows for the efficient use of a
|
||||
* static dictionary many times.
|
||||
* This is an experimental API that allows
|
||||
* efficient use of a static dictionary many times.
|
||||
*
|
||||
* Rather than re-loading the dictionary buffer into a working context before
|
||||
* each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
|
||||
|
|
@ -462,8 +461,8 @@ LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* sr
|
|||
* Currently, only streams which have been prepared by LZ4_loadDict() should
|
||||
* be expected to work.
|
||||
*
|
||||
* Alternatively, the provided dictionary stream pointer may be NULL, in which
|
||||
* case any existing dictionary stream is unset.
|
||||
* Alternatively, the provided dictionaryStream may be NULL,
|
||||
* in which case any existing dictionary stream is unset.
|
||||
*
|
||||
* If a dictionary is provided, it replaces any pre-existing stream history.
|
||||
* The dictionary contents are the only history that can be referenced and
|
||||
|
|
@ -475,17 +474,85 @@ LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* sr
|
|||
* stream (and source buffer) must remain in-place / accessible / unchanged
|
||||
* through the completion of the first compression call on the stream.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream);
|
||||
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.
|
||||
* 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.
|
||||
*
|
||||
* |<------------------------buffer--------------------------------->|
|
||||
* |<-----------compressed data--------->|
|
||||
* |<-----------decompressed size------------------>|
|
||||
* |<----margin---->|
|
||||
*
|
||||
* This technique is more useful for decompression,
|
||||
* since decompressed size is typically larger,
|
||||
* and margin is short.
|
||||
*
|
||||
* In-place decompression will work inside any buffer
|
||||
* which size is >= LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize).
|
||||
* This presumes that decompressedSize > compressedSize.
|
||||
* Otherwise, it means compression actually expanded data,
|
||||
* and it would be more efficient to store such data with a flag indicating it's not compressed.
|
||||
* This can happen when data is not compressible (already compressed, or encrypted).
|
||||
*
|
||||
* For in-place compression, margin is larger, as it must be able to cope with both
|
||||
* history preservation, requiring input data to remain unmodified up to LZ4_DISTANCE_MAX,
|
||||
* and data expansion, which can happen when input is not compressible.
|
||||
* As a consequence, buffer size requirements are much higher,
|
||||
* and memory savings offered by in-place compression are more limited.
|
||||
*
|
||||
* There are ways to limit this cost for compression :
|
||||
* - Reduce history size, by modifying LZ4_DISTANCE_MAX.
|
||||
* Note that it is a compile-time constant, so all compressions will apply this limit.
|
||||
* Lower values will reduce compression ratio, except when input_size < LZ4_DISTANCE_MAX,
|
||||
* so it's a reasonable trick when inputs are known to be small.
|
||||
* - Require the compressor to deliver a "maximum compressed size".
|
||||
* This is the `dstCapacity` parameter in `LZ4_compress*()`.
|
||||
* When this size is < LZ4_COMPRESSBOUND(inputSize), then compression can fail,
|
||||
* in which case, the return code will be 0 (zero).
|
||||
* The caller must be ready for these cases to happen,
|
||||
* and typically design a backup scheme to send data uncompressed.
|
||||
* The combination of both techniques can significantly reduce
|
||||
* the amount of margin required for in-place compression.
|
||||
*
|
||||
* In-place compression can work in any buffer
|
||||
* which size is >= (maxCompressedSize)
|
||||
* with maxCompressedSize == LZ4_COMPRESSBOUND(srcSize) for guaranteed compression success.
|
||||
* LZ4_COMPRESS_INPLACE_BUFFER_SIZE() depends on both maxCompressedSize and LZ4_DISTANCE_MAX,
|
||||
* so it's possible to reduce memory requirements by playing with them.
|
||||
*/
|
||||
|
||||
#define LZ4_DECOMPRESS_INPLACE_MARGIN(compressedSize) (((compressedSize) >> 8) + 32)
|
||||
#define LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize) ((decompressedSize) + LZ4_DECOMPRESS_INPLACE_MARGIN(decompressedSize)) /**< note: presumes that compressedSize < decompressedSize. note2: margin is overestimated a bit, since it could use compressedSize instead */
|
||||
|
||||
#ifndef LZ4_DISTANCE_MAX /* history window size; can be user-defined at compile time */
|
||||
# define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */
|
||||
#endif
|
||||
|
||||
/*-************************************
|
||||
* 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_COMPRESS_INPLACE_MARGIN (LZ4_DISTANCE_MAX + 32) /* LZ4_DISTANCE_MAX can be safely replaced by srcSize when it's smaller */
|
||||
#define LZ4_COMPRESS_INPLACE_BUFFER_SIZE(maxCompressedSize) ((maxCompressedSize) + LZ4_COMPRESS_INPLACE_MARGIN) /**< maxCompressedSize is generally LZ4_COMPRESSBOUND(inputSize), but can be set to any lower value, with the risk that compression can fail (return code 0(zero)) */
|
||||
|
||||
#endif /* LZ4_STATIC_3504398509 */
|
||||
#endif /* LZ4_STATIC_LINKING_ONLY */
|
||||
|
||||
|
||||
|
||||
#ifndef LZ4_H_98237428734687
|
||||
#define LZ4_H_98237428734687
|
||||
|
||||
/*-************************************************************
|
||||
* 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.
|
||||
**************************************************************/
|
||||
#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 */
|
||||
|
|
@ -497,7 +564,7 @@ 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 initCheck;
|
||||
uint16_t dirty;
|
||||
uint16_t tableType;
|
||||
const uint8_t* dictionary;
|
||||
const LZ4_stream_t_internal* dictCtx;
|
||||
|
|
@ -517,7 +584,7 @@ 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 initCheck;
|
||||
unsigned short dirty;
|
||||
unsigned short tableType;
|
||||
const unsigned char* dictionary;
|
||||
const LZ4_stream_t_internal* dictCtx;
|
||||
|
|
@ -526,38 +593,54 @@ struct LZ4_stream_t_internal {
|
|||
|
||||
typedef struct {
|
||||
const unsigned char* externalDict;
|
||||
size_t extDictSize;
|
||||
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.
|
||||
* 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 !
|
||||
/*! 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)
|
||||
#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))
|
||||
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 !
|
||||
/*! LZ4_initStream() : v1.9.0+
|
||||
* An LZ4_stream_t structure must be initialized at least once.
|
||||
* This is automatically done when invoking LZ4_createStream(),
|
||||
* but it's not when the structure is simply declared on stack (for example).
|
||||
*
|
||||
* Use LZ4_initStream() to properly initialize a newly declared LZ4_stream_t.
|
||||
* It can also initialize any arbitrary buffer of sufficient size,
|
||||
* and will @return a pointer of proper type upon initialization.
|
||||
*
|
||||
* Note : initialization fails if size and alignment conditions are not respected.
|
||||
* 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
|
||||
*/
|
||||
#define LZ4_STREAMDECODESIZE_U64 4
|
||||
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))
|
||||
union LZ4_streamDecode_u {
|
||||
unsigned long long table[LZ4_STREAMDECODESIZE_U64];
|
||||
|
|
@ -565,16 +648,22 @@ union LZ4_streamDecode_u {
|
|||
} ; /* previously typedef'd to LZ4_streamDecode_t */
|
||||
|
||||
|
||||
|
||||
/*-************************************
|
||||
* 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 */
|
||||
*
|
||||
* Deprecated functions make the compiler generate a warning when invoked.
|
||||
* This is meant to invite users to update their source code.
|
||||
* 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.
|
||||
*
|
||||
* Another method is to define LZ4_DISABLE_DEPRECATE_WARNINGS
|
||||
* before including the header file.
|
||||
*/
|
||||
#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
|
||||
# define LZ4_DEPRECATED(message) /* disable deprecation warnings */
|
||||
#else
|
||||
|
|
@ -594,8 +683,8 @@ union LZ4_streamDecode_u {
|
|||
#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
|
||||
|
||||
/* Obsolete compression functions */
|
||||
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* source, char* dest, int sourceSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, int maxOutputSize);
|
||||
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);
|
||||
LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
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);
|
||||
|
|
@ -616,14 +705,58 @@ LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompres
|
|||
*/
|
||||
LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer);
|
||||
LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int LZ4_sizeofStreamState(void);
|
||||
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);
|
||||
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 */
|
||||
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);
|
||||
|
||||
#endif /* LZ4_H_2983827168210 */
|
||||
/*! LZ4_decompress_fast() : **unsafe!**
|
||||
* These functions used to be faster than LZ4_decompress_safe(),
|
||||
* but it has changed, and they are now slower than LZ4_decompress_safe().
|
||||
* 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.
|
||||
* 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.
|
||||
*
|
||||
* Parameters:
|
||||
* originalSize : is the uncompressed size to regenerate.
|
||||
* `dst` must be already allocated, its size must be >= 'originalSize' bytes.
|
||||
* @return : number of bytes read from source buffer (== compressed size).
|
||||
* The function expects to finish at block's end exactly.
|
||||
* If the source stream is detected malformed, the function stops decoding and returns a negative result.
|
||||
* note : LZ4_decompress_fast*() requires originalSize. Thanks to this information, it never writes past the output buffer.
|
||||
* However, since it doesn't know its 'src' size, it may read an unknown amount of input, past input buffer bounds.
|
||||
* Also, since match offsets are not validated, match reads from 'src' may underflow too.
|
||||
* These issues never happen if input (compressed) data is correct.
|
||||
* 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")
|
||||
LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
|
||||
LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_usingDict() instead")
|
||||
LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
|
||||
|
||||
/*! LZ4_resetStream() :
|
||||
* An LZ4_stream_t structure must be initialized at least once.
|
||||
* This is done with LZ4_initStream(), or LZ4_resetStream().
|
||||
* Consider switching to LZ4_initStream(),
|
||||
* invoking LZ4_resetStream() will trigger deprecation warnings in the future.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
|
||||
|
||||
|
||||
#endif /* LZ4_H_98237428734687 */
|
||||
|
||||
|
||||
#if defined (__cplusplus)
|
||||
|
|
|
|||
Loading…
Reference in New Issue