{
if (srcCCtx->stage!=ZSTDcs_init) return ERROR(stage_wrong);
+
memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
- ZSTD_resetCCtx_advanced(dstCCtx, srcCCtx->params, pledgedSrcSize, ZSTDcrp_noMemset);
+ { ZSTD_parameters params = srcCCtx->params;
+ params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+ ZSTD_resetCCtx_advanced(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset);
+ }
/* copy tables */
{ size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog);
U32 const dictIDSizeCode = (dictID>0) + (dictID>=256) + (dictID>=65536); /* 0-3 */
U32 const checksumFlag = params.fParams.checksumFlag>0;
U32 const windowSize = 1U << params.cParams.windowLog;
- U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize > pledgedSrcSize);
+ U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize);
BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
U32 const fcsCode = params.fParams.contentSizeFlag ?
(pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : /* 0-3 */
size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize)
{
if (cdict->dictContentSize) CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize))
- else CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, cdict->refContext->params, pledgedSrcSize));
+ else {
+ ZSTD_parameters params = cdict->refContext->params;
+ params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+ CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, params, pledgedSrcSize));
+ }
return 0;
}
size_t ZSTD_CStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ; }
-size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
+static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
{
if (zcs->inBuffSize==0) return ERROR(stage_wrong); /* zcs has not been init at least once => can't reset */
return 0; /* ready to go */
}
+size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
+{
+
+ zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+
+ return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
+}
+
size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
zcs->checksum = params.fParams.checksumFlag > 0;
zcs->params = params;
- return ZSTD_resetCStream(zcs, pledgedSrcSize);
+ return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
}
/* note : cdict must outlive compression session */
ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity,
const void* src, size_t compressedSize);
-#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
-#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2)
-
-/*! ZSTD_getFrameContentSize() :
-* `src` should point to the start of a ZSTD encoded frame
-* @return : decompressed size of the frame pointed to be `src` if known, otherwise
-* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
-* - ZSTD_CONTENTSIZE_ERROR if an error occured (e.g. invalid magic number, srcSize too small) */
-ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
-
-/*! ZSTD_findDecompressedSize() :
-* `src` should point the start of a series of ZSTD encoded and/or skippable frames
-* `srcSize` must be the _exact_ size of this series
-* (i.e. there should be a frame boundary exactly `srcSize` bytes after `src`)
-* @return : the decompressed size of all data in the contained frames, as a 64-bit value _if known_
-* - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
-* - if an error occurred: ZSTD_CONTENTSIZE_ERROR
-*
-* note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
-* When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
-* In which case, it's necessary to use streaming mode to decompress data.
-* Optionally, application can still use ZSTD_decompress() while relying on implied limits.
-* (For example, data may be necessarily cut into blocks <= 16 KB).
-* note 2 : decompressed size is always present when compression is done with ZSTD_compress()
-* note 3 : decompressed size can be very large (64-bits value),
-* potentially larger than what local system can handle as a single memory segment.
-* In which case, it's necessary to use streaming mode to decompress data.
-* note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
-* Always ensure result fits within application's authorized limits.
-* Each application can set its own limits.
-* note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
-* read each contained frame header. This is efficient as most of the data is skipped,
-* however it does mean that all frame data must be present and valid. */
-ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
-
/*! ZSTD_getDecompressedSize() :
-* WARNING: This function is now obsolete. ZSTD_findDecompressedSize should be used,
-* or if only exactly one ZSTD frame is needed, ZSTD_getFrameContentSize can be used.
+* NOTE: This function is planned to be obsolete, in favour of ZSTD_findDecompressedSize,
+* or for single frames, ZSTD_getFrameContentSize. Both of the new functions return more
+* descriptive return values, disambiguating empty frames from size unknown or errors.
+* Additionally, ZSTD_findDecompressedSize handles multi-frame inputs, returning the total
+* size of all frames put together.
*
* 'src' is the start of a zstd compressed frame.
* @return : content size to be decompressed, as a 64-bits value _if known_, 0 otherwise.
#define ZSTD_MAGICNUMBER 0xFD2FB528 /* >= v0.8.0 */
#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
+#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
+#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2)
+
#define ZSTD_WINDOWLOG_MAX_32 25
#define ZSTD_WINDOWLOG_MAX_64 27
#define ZSTD_WINDOWLOG_MAX ((U32)(MEM_32bits() ? ZSTD_WINDOWLOG_MAX_32 : ZSTD_WINDOWLOG_MAX_64))
typedef void (*ZSTD_freeFunction) (void* opaque, void* address);
typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
+/***************************************
+* Decompressed size functions
+***************************************/
+/*! ZSTD_getFrameContentSize() :
+* `src` should point to the start of a ZSTD encoded frame
+* @return : decompressed size of the frame pointed to be `src` if known, otherwise
+* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
+* - ZSTD_CONTENTSIZE_ERROR if an error occured (e.g. invalid magic number, srcSize too small) */
+ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
+
+/*! ZSTD_findDecompressedSize() :
+* `src` should point the start of a series of ZSTD encoded and/or skippable frames
+* `srcSize` must be the _exact_ size of this series
+* (i.e. there should be a frame boundary exactly `srcSize` bytes after `src`)
+* @return : the decompressed size of all data in the contained frames, as a 64-bit value _if known_
+* - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
+* - if an error occurred: ZSTD_CONTENTSIZE_ERROR
+*
+* note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
+* When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
+* In which case, it's necessary to use streaming mode to decompress data.
+* Optionally, application can still use ZSTD_decompress() while relying on implied limits.
+* (For example, data may be necessarily cut into blocks <= 16 KB).
+* note 2 : decompressed size is always present when compression is done with ZSTD_compress()
+* note 3 : decompressed size can be very large (64-bits value),
+* potentially larger than what local system can handle as a single memory segment.
+* In which case, it's necessary to use streaming mode to decompress data.
+* note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+* Always ensure result fits within application's authorized limits.
+* Each application can set its own limits.
+* note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
+* read each contained frame header. This is efficient as most of the data is skipped,
+* however it does mean that all frame data must be present and valid. */
+ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+
/***************************************
* Advanced compression functions
/*===== Advanced Streaming compression functions =====*/
ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
-ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize); /**< pledgedSrcSize must be correct */
+ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize); /**< pledgedSrcSize must be correct, a size of 0 means unknown. for a frame size of 0 use initCStream_advanced */
ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize); /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */
ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict); /**< note : cdict will just be referenced, and must outlive compression session */
-ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize); /**< re-use compression parameters from previous init; skip dictionary loading stage; zcs must be init at least once before */
+ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize); /**< re-use compression parameters from previous init; skip dictionary loading stage; zcs must be init at least once before. note: pledgedSrcSize must be correct, a size of 0 means unknown. for a frame size of 0 use initCStream_advanced */
ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
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, unsigned long long pledgedSrcSize); /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */
-ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize);
-ZSTDLIB_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize);
+ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); /**< note: if pledgedSrcSize can be 0, indicating unknown size. if it is non-zero, it must be accurate. for 0 size frames, use compressBegin_advanced */
+ZSTDLIB_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize); /**< note: if pledgedSrcSize can be 0, indicating unknown size. if it is non-zero, it must be accurate. for 0 size frames, use compressBegin_advanced */
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, const void* src, size_t srcSize);
projects / thirdparty / zstd.git / commitdiff
