386 lines
18 KiB
C
386 lines
18 KiB
C
/*
|
|
LZ4 HC - High Compression Mode of LZ4
|
|
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
|
|
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
|
|
*/
|
|
#ifndef LZ4_HC_H_19834876238432
|
|
#define LZ4_HC_H_19834876238432
|
|
|
|
#if defined (__cplusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
/* --- Dependency --- */
|
|
/* note : lz4hc requires lz4.h/lz4.c for compilation */
|
|
#include "lz4.h" /* stddef, LZ4LIB_API, LZ4_DEPRECATED */
|
|
|
|
|
|
/* --- Useful constants --- */
|
|
#define LZ4HC_CLEVEL_MIN 3
|
|
#define LZ4HC_CLEVEL_DEFAULT 9
|
|
#define LZ4HC_CLEVEL_OPT_MIN 10
|
|
#define LZ4HC_CLEVEL_MAX 12
|
|
|
|
|
|
/*-************************************
|
|
* Block Compression
|
|
**************************************/
|
|
/*! LZ4_compress_HC() :
|
|
* Compress data from `src` into `dst`, using the more powerful but slower "HC" algorithm.
|
|
* `dst` must be already allocated.
|
|
* Compression is guaranteed to succeed if `dstCapacity >= LZ4_compressBound(srcSize)` (see "lz4.h")
|
|
* Max supported `srcSize` value is LZ4_MAX_INPUT_SIZE (see "lz4.h")
|
|
* `compressionLevel` : any value between 1 and LZ4HC_CLEVEL_MAX will work.
|
|
* Values > LZ4HC_CLEVEL_MAX behave the same as LZ4HC_CLEVEL_MAX.
|
|
* @return : the number of bytes written into 'dst'
|
|
* or 0 if compression fails.
|
|
*/
|
|
LZ4LIB_API int LZ4_compress_HC (const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel);
|
|
|
|
|
|
/* Note :
|
|
* Decompression functions are provided within "lz4.h" (BSD license)
|
|
*/
|
|
|
|
|
|
/*! LZ4_compress_HC_extStateHC() :
|
|
* Same as LZ4_compress_HC(), but using an externally allocated memory segment for `state`.
|
|
* `state` size is provided by LZ4_sizeofStateHC().
|
|
* Memory segment must be aligned on 8-bytes boundaries (which a normal malloc() should do properly).
|
|
*/
|
|
LZ4LIB_API int LZ4_sizeofStateHC(void);
|
|
LZ4LIB_API int LZ4_compress_HC_extStateHC(void* state, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel);
|
|
|
|
|
|
/*-************************************
|
|
* Streaming Compression
|
|
* Bufferless synchronous API
|
|
**************************************/
|
|
typedef union LZ4_streamHC_u LZ4_streamHC_t; /* incomplete type (defined later) */
|
|
|
|
/*! LZ4_createStreamHC() and LZ4_freeStreamHC() :
|
|
* These functions create and release memory for LZ4 HC streaming state.
|
|
* Newly created states are automatically initialized.
|
|
* Existing states can be re-used several times, using LZ4_resetStreamHC().
|
|
* These methods are API and ABI stable, they can be used in combination with a DLL.
|
|
*/
|
|
LZ4LIB_API LZ4_streamHC_t* LZ4_createStreamHC(void);
|
|
LZ4LIB_API int LZ4_freeStreamHC (LZ4_streamHC_t* streamHCPtr);
|
|
|
|
LZ4LIB_API void LZ4_resetStreamHC (LZ4_streamHC_t* streamHCPtr, int compressionLevel);
|
|
LZ4LIB_API int LZ4_loadDictHC (LZ4_streamHC_t* streamHCPtr, const char* dictionary, int dictSize);
|
|
|
|
LZ4LIB_API int LZ4_compress_HC_continue (LZ4_streamHC_t* streamHCPtr, const char* src, char* dst, int srcSize, int maxDstSize);
|
|
|
|
LZ4LIB_API int LZ4_saveDictHC (LZ4_streamHC_t* streamHCPtr, char* safeBuffer, int maxDictSize);
|
|
|
|
/*
|
|
These functions compress data in successive blocks of any size, using previous blocks as dictionary.
|
|
One key assumption is that previous blocks (up to 64 KB) remain read-accessible while compressing next blocks.
|
|
There is an exception for ring buffers, which can be smaller than 64 KB.
|
|
Ring buffers scenario is automatically detected and handled by LZ4_compress_HC_continue().
|
|
|
|
Before starting compression, state must be properly initialized, using LZ4_resetStreamHC().
|
|
A first "fictional block" can then be designated as initial dictionary, using LZ4_loadDictHC() (Optional).
|
|
|
|
Then, use LZ4_compress_HC_continue() to compress each successive block.
|
|
Previous memory blocks (including initial dictionary when present) must remain accessible and unmodified during compression.
|
|
'dst' buffer should be sized to handle worst case scenarios (see LZ4_compressBound()), to ensure operation success.
|
|
Because in case of failure, the API does not guarantee context recovery, and context will have to be reset.
|
|
If `dst` buffer budget cannot be >= LZ4_compressBound(), consider using LZ4_compress_HC_continue_destSize() instead.
|
|
|
|
If, for any reason, previous data block can't be preserved unmodified in memory for next compression block,
|
|
you can save it to a more stable memory space, using LZ4_saveDictHC().
|
|
Return value of LZ4_saveDictHC() is the size of dictionary effectively saved into 'safeBuffer'.
|
|
*/
|
|
|
|
|
|
|
|
|
|
/*^**********************************************
|
|
* !!!!!! STATIC LINKING ONLY !!!!!!
|
|
***********************************************/
|
|
|
|
/*-******************************************************************
|
|
* PRIVATE DEFINITIONS :
|
|
* Do not use these definitions directly.
|
|
* They are merely exposed to allow static allocation of `LZ4_streamHC_t`.
|
|
* Declare an `LZ4_streamHC_t` directly, rather than any type below.
|
|
* Even then, only do so in the context of static linking, as definitions may change between versions.
|
|
********************************************************************/
|
|
|
|
#define LZ4HC_DICTIONARY_LOGSIZE 16
|
|
#define LZ4HC_MAXD (1<<LZ4HC_DICTIONARY_LOGSIZE)
|
|
#define LZ4HC_MAXD_MASK (LZ4HC_MAXD - 1)
|
|
|
|
#define LZ4HC_HASH_LOG 15
|
|
#define LZ4HC_HASHTABLESIZE (1 << LZ4HC_HASH_LOG)
|
|
#define LZ4HC_HASH_MASK (LZ4HC_HASHTABLESIZE - 1)
|
|
|
|
|
|
#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
|
|
#include <stdint.h>
|
|
|
|
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
|
|
|
|
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 */
|
|
const LZ4HC_CCtx_internal* dictCtx;
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
/* do not use these definitions directly.
|
|
* 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))
|
|
union LZ4_streamHC_u {
|
|
size_t table[LZ4_STREAMHCSIZE_SIZET];
|
|
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.
|
|
* State must be initialized using LZ4_resetStreamHC() before first use.
|
|
*
|
|
* Static allocation shall only be used in combination with static linking.
|
|
* When invoking LZ4 from a DLL, use create/free functions instead, which are API and ABI stable.
|
|
*/
|
|
|
|
|
|
/*-************************************
|
|
* Deprecated Functions
|
|
**************************************/
|
|
/* see lz4.h LZ4_DISABLE_DEPRECATE_WARNINGS to turn off deprecation warnings */
|
|
|
|
/* deprecated compression functions */
|
|
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC (const char* source, char* dest, int inputSize);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize);
|
|
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
|
|
|
|
/* Obsolete streaming functions; 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
|
|
* possible: using them will still produce a correct output. However, use of
|
|
* LZ4_slideInputBufferHC() will truncate the history of the stream, rather
|
|
* than preserve a window-sized chunk of history.
|
|
*/
|
|
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);
|
|
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);
|
|
LZ4_DEPRECATED("use LZ4_resetStreamHC() instead") LZ4LIB_API int LZ4_resetStreamStateHC(void* state, char* inputBuffer);
|
|
|
|
|
|
#if defined (__cplusplus)
|
|
}
|
|
#endif
|
|
|
|
#endif /* LZ4_HC_H_19834876238432 */
|
|
|
|
|
|
/*-**************************************************
|
|
* !!!!! STATIC LINKING ONLY !!!!!
|
|
* Following definitions are considered experimental.
|
|
* 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.
|
|
***************************************************/
|
|
#ifdef LZ4_HC_STATIC_LINKING_ONLY /* protection macro */
|
|
#ifndef LZ4_HC_SLO_098092834
|
|
#define LZ4_HC_SLO_098092834
|
|
|
|
#if defined (__cplusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
/*! LZ4_compress_HC_destSize() : v1.8.0 (experimental)
|
|
* Will try to compress as much data from `src` as possible
|
|
* that can fit into `targetDstSize` budget.
|
|
* Result is provided in 2 parts :
|
|
* @return : the number of bytes written into 'dst'
|
|
* or 0 if compression fails.
|
|
* `srcSizePtr` : value will be updated to indicate how much bytes were read from `src`
|
|
*/
|
|
LZ4LIB_STATIC_API int LZ4_compress_HC_destSize(
|
|
void* LZ4HC_Data,
|
|
const char* src, char* dst,
|
|
int* srcSizePtr, int targetDstSize,
|
|
int compressionLevel);
|
|
|
|
/*! LZ4_compress_HC_continue_destSize() : v1.8.0 (experimental)
|
|
* Similar as LZ4_compress_HC_continue(),
|
|
* but will read a variable nb of bytes from `src`
|
|
* to fit into `targetDstSize` budget.
|
|
* Result is provided in 2 parts :
|
|
* @return : the number of bytes written into 'dst'
|
|
* or 0 if compression fails.
|
|
* `srcSizePtr` : value will be updated to indicate how much bytes were read from `src`.
|
|
*/
|
|
LZ4LIB_STATIC_API int LZ4_compress_HC_continue_destSize(
|
|
LZ4_streamHC_t* LZ4_streamHCPtr,
|
|
const char* src, char* dst,
|
|
int* srcSizePtr, int targetDstSize);
|
|
|
|
/*! LZ4_setCompressionLevel() : v1.8.0 (experimental)
|
|
* It's possible to change compression level between 2 invocations of LZ4_compress_HC_continue*()
|
|
*/
|
|
LZ4LIB_STATIC_API void LZ4_setCompressionLevel(
|
|
LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel);
|
|
|
|
/*! LZ4_favorDecompressionSpeed() : v1.8.2 (experimental)
|
|
* Parser will select decisions favoring decompression over compression ratio.
|
|
* Only work at highest compression settings (level >= LZ4HC_CLEVEL_OPT_MIN)
|
|
*/
|
|
LZ4LIB_STATIC_API void LZ4_favorDecompressionSpeed(
|
|
LZ4_streamHC_t* LZ4_streamHCPtr, int favor);
|
|
|
|
/*! LZ4_resetStreamHC_fast() :
|
|
* When an LZ4_streamHC_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_resetStreamHC()).
|
|
*
|
|
* LZ4_streamHCs are guaranteed to be in a valid state when:
|
|
* - returned from LZ4_createStreamHC()
|
|
* - reset by LZ4_resetStreamHC()
|
|
* - memset(stream, 0, sizeof(LZ4_streamHC_t))
|
|
* - the stream was in a valid state and was reset by LZ4_resetStreamHC_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 (LZ4_compress_HC_extStateHC()) and that
|
|
* returned success
|
|
*
|
|
* Note:
|
|
* A stream that was last used in a compression call that returned an error
|
|
* may be passed to this function. However, it will be fully reset, which will
|
|
* clear any existing history and settings from the context.
|
|
*/
|
|
LZ4LIB_STATIC_API void LZ4_resetStreamHC_fast(
|
|
LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel);
|
|
|
|
/*! LZ4_compress_HC_extStateHC_fastReset() :
|
|
* A variant of LZ4_compress_HC_extStateHC().
|
|
*
|
|
* 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_resetStreamHC_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
|
|
* LZ4_resetStreamHC_fast() while LZ4_compress_HC_extStateHC() starts with a
|
|
* call to LZ4_resetStreamHC().
|
|
*/
|
|
LZ4LIB_STATIC_API int LZ4_compress_HC_extStateHC_fastReset (
|
|
void* state,
|
|
const char* src, char* dst,
|
|
int srcSize, int dstCapacity,
|
|
int compressionLevel);
|
|
|
|
/*! LZ4_attach_HC_dictionary() :
|
|
* This is an experimental API that allows for the 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_streamHC_t into a
|
|
* working LZ4_streamHC_t, this function introduces a no-copy setup mechanism,
|
|
* in which the working stream references the dictionary stream in-place.
|
|
*
|
|
* Several assumptions are made about the state of the dictionary stream.
|
|
* Currently, only streams which have been prepared by LZ4_loadDictHC() should
|
|
* be expected to work.
|
|
*
|
|
* Alternatively, the provided dictionary stream pointer may be NULL, in which
|
|
* case any existing dictionary stream is unset.
|
|
*
|
|
* A dictionary should only be attached to a stream without any history (i.e.,
|
|
* a stream that has just been reset).
|
|
*
|
|
* The dictionary will remain attached to the working stream only for the
|
|
* current stream session. Calls to LZ4_resetStreamHC(_fast) will remove the
|
|
* dictionary context association from the working stream. The dictionary
|
|
* stream (and source buffer) must remain in-place / accessible / unchanged
|
|
* through the lifetime of the stream session.
|
|
*/
|
|
LZ4LIB_STATIC_API void LZ4_attach_HC_dictionary(
|
|
LZ4_streamHC_t *working_stream,
|
|
const LZ4_streamHC_t *dictionary_stream);
|
|
|
|
#if defined (__cplusplus)
|
|
}
|
|
#endif
|
|
|
|
#endif /* LZ4_HC_SLO_098092834 */
|
|
#endif /* LZ4_HC_STATIC_LINKING_ONLY */
|