Merged zstd_static.h into zstd.h . Now requires ZSTD_STATIC_LINKING_ONLY macro

This commit is contained in:
Yann Collet
2016-06-04 19:47:02 +02:00
parent ac110a1f21
commit d3b7f8d21f
15 changed files with 296 additions and 332 deletions
+261 -3
View File
@@ -29,8 +29,8 @@
You can contact the author at :
- zstd source repository : https://github.com/Cyan4973/zstd
*/
#ifndef ZSTD_H
#define ZSTD_H
#ifndef ZSTD_H_235446
#define ZSTD_H_235446
#if defined (__cplusplus)
extern "C" {
@@ -148,8 +148,266 @@ ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
const void* dict,size_t dictSize);
#ifdef ZSTD_STATIC_LINKING_ONLY
/* ====================================================================================
* The definitions in this section are considered experimental.
* They should never be used in association with a dynamic library, as they may change in the future.
* They are provided for advanced usages.
* Use them only in association with static linking.
* ==================================================================================== */
/*--- Dependency ---*/
#include "mem.h"
/*--- Constants ---*/
#define ZSTD_MAGICNUMBER 0xFD2FB526 /* v0.6 */
#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
#define ZSTD_WINDOWLOG_MAX ((U32)(MEM_32bits() ? 25 : 27))
#define ZSTD_WINDOWLOG_MIN 18
#define ZSTD_CHAINLOG_MAX (ZSTD_WINDOWLOG_MAX+1)
#define ZSTD_CHAINLOG_MIN 4
#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX
#define ZSTD_HASHLOG_MIN 12
#define ZSTD_HASHLOG3_MAX 17
#define ZSTD_HASHLOG3_MIN 15
#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
#define ZSTD_SEARCHLOG_MIN 1
#define ZSTD_SEARCHLENGTH_MAX 7
#define ZSTD_SEARCHLENGTH_MIN 3
#define ZSTD_TARGETLENGTH_MIN 4
#define ZSTD_TARGETLENGTH_MAX 999
/*--- Types ---*/
typedef enum { ZSTD_fast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2, ZSTD_btlazy2, ZSTD_btopt } ZSTD_strategy; /* from faster to stronger */
typedef struct {
U32 windowLog; /* largest match distance : larger == more compression, more memory needed during decompression */
U32 chainLog; /* fully searched segment : larger == more compression, slower, more memory (useless for fast) */
U32 hashLog; /* dispatch table : larger == faster, more memory */
U32 searchLog; /* nb of searches : larger == more compression, slower */
U32 searchLength; /* match length searched : larger == faster decompression, sometimes less compression */
U32 targetLength; /* acceptable match size for optimal parser (only) : larger == more compression, slower */
ZSTD_strategy strategy;
} ZSTD_compressionParameters;
typedef struct {
U32 contentSizeFlag; /* 1: content size will be in frame header (if known). */
U32 checksumFlag; /* 1: will generate a 22-bits checksum at end of frame, to be used for error detection by decompressor */
U32 noDictIDFlag; /* 1: no dict ID will be saved into frame header (if dictionary compression) */
} ZSTD_frameParameters;
typedef struct {
ZSTD_compressionParameters cParams;
ZSTD_frameParameters fParams;
} ZSTD_parameters;
/* custom memory allocation functions */
typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
typedef void (*ZSTD_freeFunction) (void* opaque, void* address);
typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
/*-*************************************
* Advanced functions
***************************************/
/*! ZSTD_createCCtx_advanced() :
* Create a ZSTD compression context using external alloc and free functions */
ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
/*! ZSTD_createDCtx_advanced() :
* Create a ZSTD decompression context using external alloc and free functions */
ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem);
ZSTDLIB_API unsigned ZSTD_maxCLevel (void);
/*! ZSTD_getCParams() :
* @return ZSTD_compressionParameters structure for a selected compression level and srcSize.
* `srcSize` value is optional, select 0 if not known */
ZSTDLIB_API ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, U64 srcSize, size_t dictSize);
/*! ZSTD_checkParams() :
* Ensure param values remain within authorized range */
ZSTDLIB_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params);
/*! ZSTD_adjustParams() :
* optimize params for a given `srcSize` and `dictSize`.
* both values are optional, select `0` if unknown. */
ZSTDLIB_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, U64 srcSize, size_t dictSize);
/*! ZSTD_compress_advanced() :
* Same as ZSTD_compress_usingDict(), with fine-tune control of each compression parameter */
ZSTDLIB_API size_t ZSTD_compress_advanced (ZSTD_CCtx* ctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict,size_t dictSize,
ZSTD_parameters params);
/*! ZSTD_compress_usingPreparedDCtx() :
* Same as ZSTD_compress_usingDict, but using a reference context `preparedCCtx`, where dictionary has been loaded.
* It avoids reloading the dictionary each time.
* `preparedCCtx` must have been properly initialized using ZSTD_compressBegin_usingDict() or ZSTD_compressBegin_advanced().
* Requires 2 contexts : 1 for reference (preparedCCtx) which will not be modified, and 1 to run the compression operation (cctx) */
ZSTDLIB_API size_t ZSTD_compress_usingPreparedCCtx(
ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize);
/*- Advanced Decompression functions -*/
/*! ZSTD_decompress_usingPreparedDCtx() :
* Same as ZSTD_decompress_usingDict, but using a reference context `preparedDCtx`, where dictionary has been loaded.
* It avoids reloading the dictionary each time.
* `preparedDCtx` must have been properly initialized using ZSTD_decompressBegin_usingDict().
* Requires 2 contexts : 1 for reference (preparedDCtx), which will not be modified, and 1 to run the decompression operation (dctx) */
ZSTDLIB_API size_t ZSTD_decompress_usingPreparedDCtx(
ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize);
/* **************************************
* Streaming functions (direct mode)
****************************************/
ZSTDLIB_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
ZSTDLIB_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
ZSTDLIB_API size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, U64 pledgedSrcSize);
ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx);
ZSTDLIB_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity);
/*
Streaming compression, synchronous mode (bufferless)
A ZSTD_CCtx object is required to track streaming operations.
Use ZSTD_createCCtx() / ZSTD_freeCCtx() to manage it.
ZSTD_CCtx object can be re-used multiple times within successive compression operations.
Start by initializing a context.
Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary compression,
or ZSTD_compressBegin_advanced(), for finer parameter control.
It's also possible to duplicate a reference context which has already been initialized, using ZSTD_copyCCtx()
Then, consume your input using ZSTD_compressContinue().
The interface is synchronous, so all input will be consumed and produce a compressed output.
You must ensure there is enough space in destination buffer to store compressed data under worst case scenario.
Worst case evaluation is provided by ZSTD_compressBound().
Finish a frame with ZSTD_compressEnd(), which will write the epilogue.
Without the epilogue, frames will be considered incomplete by decoder.
You can then reuse ZSTD_CCtx to compress some new frame.
*/
typedef struct {
U64 frameContentSize;
U32 windowLog;
U32 dictID;
U32 checksumFlag;
} ZSTD_frameParams;
#define ZSTD_FRAMEHEADERSIZE_MAX 18 /* for static allocation */
static const size_t ZSTD_frameHeaderSize_min = 6;
static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
static const size_t ZSTD_skippableHeaderSize = 8; /* magic number + skippable frame length */
ZSTDLIB_API size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input */
ZSTDLIB_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
ZSTDLIB_API void ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx);
ZSTDLIB_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
/*
Streaming decompression, direct mode (bufferless)
A ZSTD_DCtx object is required to track streaming operations.
Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
A ZSTD_DCtx object can be re-used multiple times.
First optional operation is to retrieve frame parameters, using ZSTD_getFrameParams(), which doesn't consume the input.
It can provide the minimum size of rolling buffer required to properly decompress data,
and optionally the final size of uncompressed content.
(Note : content size is an optional info that may not be present. 0 means : content size unknown)
Frame parameters are extracted from the beginning of compressed frame.
The amount of data to read is variable, from ZSTD_frameHeaderSize_min to ZSTD_frameHeaderSize_max (so if `srcSize` >= ZSTD_frameHeaderSize_max, it will always work)
If `srcSize` is too small for operation to succeed, function will return the minimum size it requires to produce a result.
Result : 0 when successful, it means the ZSTD_frameParams structure has been filled.
>0 : means there is not enough data into `src`. Provides the expected size to successfully decode header.
errorCode, which can be tested using ZSTD_isError()
Start decompression, with ZSTD_decompressBegin() or ZSTD_decompressBegin_usingDict().
Alternatively, you can copy a prepared context, using ZSTD_copyDCtx().
Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue().
ZSTD_decompressContinue() requires this exact amount of bytes, or it will fail.
ZSTD_decompressContinue() needs previous data blocks during decompression, up to (1 << windowlog).
They should preferably be located contiguously, prior to current block. Alternatively, a round buffer is also possible.
@result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity)
It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header.
A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
Context can then be reset to start a new decompression.
Skippable frames allow the integration of user-defined data into a flow of concatenated frames.
Skippable frames will be ignored (skipped) by a decompressor. The format of skippable frame is following:
a) Skippable frame ID - 4 Bytes, Little endian format, any value from 0x184D2A50 to 0x184D2A5F
b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
c) Frame Content - any content (User Data) of length equal to Frame Size
For skippable frames ZSTD_decompressContinue() always returns 0.
For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
It also returns Frame Size as fparamsPtr->frameContentSize.
*/
/* **************************************
* Block functions
****************************************/
/*! Block functions produce and decode raw zstd blocks, without frame metadata.
User will have to take in charge required information to regenerate data, such as compressed and content sizes.
A few rules to respect :
- Uncompressed block size must be <= ZSTD_BLOCKSIZE_MAX (128 KB)
- Compressing or decompressing requires a context structure
+ Use ZSTD_createCCtx() and ZSTD_createDCtx()
- It is necessary to init context before starting
+ compression : ZSTD_compressBegin()
+ decompression : ZSTD_decompressBegin()
+ variants _usingDict() are also allowed
+ copyCCtx() and copyDCtx() work too
- When a block is considered not compressible enough, ZSTD_compressBlock() result will be zero.
In which case, nothing is produced into `dst`.
+ User must test for such outcome and deal directly with uncompressed data
+ ZSTD_decompressBlock() doesn't accept uncompressed data as input !!
*/
#define ZSTD_BLOCKSIZE_MAX (128 * 1024) /* define, for static allocation */
ZSTDLIB_API size_t ZSTD_compressBlock (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
ZSTDLIB_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
/*-*************************************
* Error management
***************************************/
#include "error_public.h"
/*! ZSTD_getErrorCode() :
convert a `size_t` function result into a `ZSTD_ErrorCode` enum type,
which can be used to compare directly with enum list published into "error_public.h" */
ZSTDLIB_API ZSTD_ErrorCode ZSTD_getErrorCode(size_t functionResult);
ZSTDLIB_API const char* ZSTD_getErrorString(ZSTD_ErrorCode code);
#endif /* ZSTD_STATIC_LINKING_ONLY */
#if defined (__cplusplus)
}
#endif
#endif /* ZSTD_H */
#endif /* ZSTD_H_235446 */