Compress-Zstd
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ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output,
+ ZSTD_inBuffer *input);
+/**
+ * ZSTD_flushStream() - flush internal buffers into output
+ * @zcs: The zstd streaming compression context.
+ * @output: Destination buffer. `output->pos` is updated to indicate how much
+ * compressed data was written.
+ *
+ * ZSTD_flushStream() must be called until it returns 0, meaning all the data
+ * has been flushed. Since ZSTD_flushStream() causes a block to be ended,
+ * calling it too often will degrade the compression ratio.
+ *
+ * Return: The number of bytes still present within internal buffers or an
+ * error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
+/**
+ * ZSTD_endStream() - flush internal buffers into output and end the frame
+ * @zcs: The zstd streaming compression context.
+ * @output: Destination buffer. `output->pos` is updated to indicate how much
+ * compressed data was written.
+ *
+ * ZSTD_endStream() must be called until it returns 0, meaning all the data has
+ * been flushed and the frame epilogue has been written.
+ *
+ * Return: The number of bytes still present within internal buffers or an
+ * error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
+
+/**
+ * ZSTD_CStreamInSize() - recommended size for the input buffer
+ *
+ * Return: The recommended size for the input buffer.
+ */
+size_t ZSTD_CStreamInSize(void);
+/**
+ * ZSTD_CStreamOutSize() - recommended size for the output buffer
+ *
+ * When the output buffer is at least this large, it is guaranteed to be large
+ * enough to flush at least one complete compressed block.
+ *
+ * Return: The recommended size for the output buffer.
+ */
+size_t ZSTD_CStreamOutSize(void);
+
+
+
+/*-*****************************************************************************
+ * Streaming decompression - HowTo
+ *
+ * A ZSTD_DStream object is required to track streaming operations.
+ * Use ZSTD_initDStream() to initialize a ZSTD_DStream object.
+ * ZSTD_DStream objects can be re-used multiple times.
+ *
+ * Use ZSTD_decompressStream() repetitively to consume your input.
+ * The function will update both `pos` fields.
+ * If `input->pos < input->size`, some input has not been consumed.
+ * It's up to the caller to present again remaining data.
+ * If `output->pos < output->size`, decoder has flushed everything it could.
+ * Returns 0 iff a frame is completely decoded and fully flushed.
+ * Otherwise it returns a suggested next input size that will never load more
+ * than the current frame.
+ ******************************************************************************/
+
+/**
+ * ZSTD_DStreamWorkspaceBound() - memory needed to initialize a ZSTD_DStream
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initDStream() and ZSTD_initDStream_usingDDict().
+ */
+size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize);
+
+/**
+ * struct ZSTD_DStream - the zstd streaming decompression context
+ */
+typedef struct ZSTD_DStream_s ZSTD_DStream;
+/*===== ZSTD_DStream management functions =====*/
+/**
+ * ZSTD_initDStream() - initialize a zstd streaming decompression context
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace.
+ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming decompression context.
+ */
+ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace,
+ size_t workspaceSize);
+/**
+ * ZSTD_initDStream_usingDDict() - initialize streaming decompression context
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ * @ddict: The digested dictionary to use for decompression.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace.
+ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming decompression context.
+ */
+ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize,
+ const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize);
+
+/*===== Streaming decompression functions =====*/
+/**
+ * ZSTD_resetDStream() - reset the context using parameters from creation
+ * @zds: The zstd streaming decompression context to reset.
+ *
+ * Resets the context using the parameters from creation. Skips dictionary
+ * loading, since it can be reused.
+ *
+ * Return: Zero or an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_resetDStream(ZSTD_DStream *zds);
+/**
+ * ZSTD_decompressStream() - streaming decompress some of input into output
+ * @zds: The zstd streaming decompression context.
+ * @output: Destination buffer. `output.pos` is updated to indicate how much
+ * decompressed data was written.
+ * @input: Source buffer. `input.pos` is updated to indicate how much data was
+ * read. Note that it may not consume the entire input, in which case
+ * `input.pos < input.size`, and it's up to the caller to present
+ * remaining data again.
+ *
+ * The `input` and `output` buffers may be any size. Guaranteed to make some
+ * forward progress if `input` and `output` are not empty.
+ * ZSTD_decompressStream() will not consume the last byte of the frame until
+ * the entire frame is flushed.
+ *
+ * Return: Returns 0 iff a frame is completely decoded and fully flushed.
+ * Otherwise returns a hint for the number of bytes to use as the input
+ * for the next function call or an error, which can be checked using
+ * ZSTD_isError(). The size hint will never load more than the frame.
+ */
+size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output,
+ ZSTD_inBuffer *input);
+
+/**
+ * ZSTD_DStreamInSize() - recommended size for the input buffer
+ *
+ * Return: The recommended size for the input buffer.
+ */
+size_t ZSTD_DStreamInSize(void);
+/**
+ * ZSTD_DStreamOutSize() - recommended size for the output buffer
+ *
+ * When the output buffer is at least this large, it is guaranteed to be large
+ * enough to flush at least one complete decompressed block.
+ *
+ * Return: The recommended size for the output buffer.
+ */
+size_t ZSTD_DStreamOutSize(void);
+
+
+/* --- Constants ---*/
+#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 27
+#define ZSTD_WINDOWLOG_MAX_64 27
+#define ZSTD_WINDOWLOG_MAX \
+ ((unsigned int)(sizeof(size_t) == 4 \
+ ? ZSTD_WINDOWLOG_MAX_32 \
+ : ZSTD_WINDOWLOG_MAX_64))
+#define ZSTD_WINDOWLOG_MIN 10
+#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX
+#define ZSTD_HASHLOG_MIN 6
+#define ZSTD_CHAINLOG_MAX (ZSTD_WINDOWLOG_MAX+1)
+#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN
+#define ZSTD_HASHLOG3_MAX 17
+#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
+#define ZSTD_SEARCHLOG_MIN 1
+/* only for ZSTD_fast, other strategies are limited to 6 */
+#define ZSTD_SEARCHLENGTH_MAX 7
+/* only for ZSTD_btopt, other strategies are limited to 4 */
+#define ZSTD_SEARCHLENGTH_MIN 3
+#define ZSTD_TARGETLENGTH_MIN 4
+#define ZSTD_TARGETLENGTH_MAX 999
+
+/* for static allocation */
+#define ZSTD_FRAMEHEADERSIZE_MAX 18
+#define ZSTD_FRAMEHEADERSIZE_MIN 6
+static const size_t ZSTD_frameHeaderSize_prefix = 5;
+static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
+static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
+/* magic number + skippable frame length */
+static const size_t ZSTD_skippableHeaderSize = 8;
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ * Advanced compression functions
+ **************************************/
+/**
+ * ZSTD_checkCParams() - ensure parameter values remain within authorized range
+ * @cParams: The zstd compression parameters.
+ *
+ * Return: Zero or an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams);
+
+/**
+ * ZSTD_adjustCParams() - optimize parameters for a given srcSize and dictSize
+ * @srcSize: Optionally the estimated source size, or zero if unknown.
+ * @dictSize: Optionally the estimated dictionary size, or zero if unknown.
+ *
+ * Return: The optimized parameters.
+ */
+ZSTD_compressionParameters ZSTD_adjustCParams(
+ ZSTD_compressionParameters cParams, unsigned long long srcSize,
+ size_t dictSize);
+
+/*--- Advanced decompression functions ---*/
+
+/**
+ * ZSTD_isFrame() - returns true iff the buffer starts with a valid frame
+ * @buffer: The source buffer to check.
+ * @size: The size of the source buffer, must be at least 4 bytes.
+ *
+ * Return: True iff the buffer starts with a zstd or skippable frame identifier.
+ */
+unsigned int ZSTD_isFrame(const void *buffer, size_t size);
+
+/**
+ * ZSTD_getDictID_fromDict() - returns the dictionary id stored in a dictionary
+ * @dict: The dictionary buffer.
+ * @dictSize: The size of the dictionary buffer.
+ *
+ * Return: The dictionary id stored within the dictionary or 0 if the
+ * dictionary is not a zstd dictionary. If it returns 0 the
+ * dictionary can still be loaded as a content-only dictionary.
+ */
+unsigned int ZSTD_getDictID_fromDict(const void *dict, size_t dictSize);
+
+/**
+ * ZSTD_getDictID_fromDDict() - returns the dictionary id stored in a ZSTD_DDict
+ * @ddict: The ddict to find the id of.
+ *
+ * Return: The dictionary id stored within `ddict` or 0 if the dictionary is not
+ * a zstd dictionary. If it returns 0 `ddict` will be loaded as a
+ * content-only dictionary.
+ */
+unsigned int ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict);
+
+/**
+ * ZSTD_getDictID_fromFrame() - returns the dictionary id stored in a zstd frame
+ * @src: Source buffer. It must be a zstd encoded frame.
+ * @srcSize: The size of the source buffer. It must be at least as large as the
+ * frame header. `ZSTD_frameHeaderSize_max` is always large enough.
+ *
+ * Return: The dictionary id required to decompress the frame stored within
+ * `src` or 0 if the dictionary id could not be decoded. It can return
+ * 0 if the frame does not require a dictionary, the dictionary id
+ * wasn't stored in the frame, `src` is not a zstd frame, or `srcSize`
+ * is too small.
+ */
+unsigned int ZSTD_getDictID_fromFrame(const void *src, size_t srcSize);
+
+/**
+ * struct ZSTD_frameParams - zstd frame parameters stored in the frame header
+ * @frameContentSize: The frame content size, or 0 if not present.
+ * @windowSize: The window size, or 0 if the frame is a skippable frame.
+ * @dictID: The dictionary id, or 0 if not present.
+ * @checksumFlag: Whether a checksum was used.
+ */
+typedef struct {
+ unsigned long long frameContentSize;
+ unsigned int windowSize;
+ unsigned int dictID;
+ unsigned int checksumFlag;
+} ZSTD_frameParams;
+
+/**
+ * ZSTD_getFrameParams() - extracts parameters from a zstd or skippable frame
+ * @fparamsPtr: On success the frame parameters are written here.
+ * @src: The source buffer. It must point to a zstd or skippable frame.
+ * @srcSize: The size of the source buffer. `ZSTD_frameHeaderSize_max` is
+ * always large enough to succeed.
+ *
+ * Return: 0 on success. If more data is required it returns how many bytes
+ * must be provided to make forward progress. Otherwise it returns
+ * an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src,
+ size_t srcSize);
+
+/*-*****************************************************************************
+ * Buffer-less and synchronous inner streaming functions
+ *
+ * This is an advanced API, giving full control over buffer management, for
+ * users which need direct control over memory.
+ * But it's also a complex one, with many restrictions (documented below).
+ * Prefer using normal streaming API for an easier experience
+ ******************************************************************************/
+
+/*-*****************************************************************************
+ * Buffer-less streaming compression (synchronous mode)
+ *
+ * A ZSTD_CCtx object is required to track streaming operations.
+ * Use ZSTD_initCCtx() to initialize a context.
+ * 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().
+ * There are some important considerations to keep in mind when using this
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ * frame.
+ ******************************************************************************/
+
+/*===== Buffer-less streaming compression functions =====*/
+size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel);
+size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict,
+ size_t dictSize, int compressionLevel);
+size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict,
+ size_t dictSize, ZSTD_parameters params,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_copyCCtx(ZSTD_CCtx *cctx, const ZSTD_CCtx *preparedCCtx,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+
+
+
+/*-*****************************************************************************
+ * Buffer-less streaming decompression (synchronous mode)
+ *
+ * A ZSTD_DCtx object is required to track streaming operations.
+ * Use ZSTD_initDCtx() to initialize a context.
+ * A ZSTD_DCtx object can be re-used multiple times.
+ *
+ * First typical operation is to retrieve frame parameters, using
+ * ZSTD_getFrameParams(). It fills a ZSTD_frameParams structure which provide
+ * important information to correctly decode the frame, such as the minimum
+ * rolling buffer size to allocate to decompress data (`windowSize`), and the
+ * dictionary ID used.
+ * Note: content size is optional, it may not be present. 0 means unknown.
+ * Note that these values could be wrong, either because of data malformation,
+ * or because an attacker is spoofing deliberate false information. As a
+ * consequence, check that values remain within valid application range,
+ * especially `windowSize`, before allocation. Each application can set its own
+ * limit, depending on local restrictions. For extended interoperability, it is
+ * recommended to support at least 8 MB.
+ * Frame parameters are extracted from the beginning of the compressed frame.
+ * Data fragment must be large enough to ensure successful decoding, typically
+ * `ZSTD_frameHeaderSize_max` bytes.
+ * Result: 0: successful decoding, the `ZSTD_frameParams` structure is filled.
+ * >0: `srcSize` is too small, provide at least this many bytes.
+ * 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 many bytes to provide as 'srcSize'
+ * to ZSTD_decompressContinue().
+ * ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will
+ * fail.
+ *
+ * The 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 metadata
+ * item. It can also be an error code, which can be tested with ZSTD_isError().
+ *
+ * ZSTD_decompressContinue() needs previous data blocks during decompression, up
+ * to `windowSize`. They should preferably be located contiguously, prior to
+ * current block. Alternatively, a round buffer of sufficient size is also
+ * possible. Sufficient size is determined by frame parameters.
+ * ZSTD_decompressContinue() is very sensitive to contiguity, if 2 blocks don't
+ * follow each other, make sure that either the compressor breaks contiguity at
+ * the same place, or that previous contiguous segment is large enough to
+ * properly handle maximum back-reference.
+ *
+ * A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
+ * Context can then be reset to start a new decompression.
+ *
+ * Note: it's possible to know if next input to present is a header or a block,
+ * using ZSTD_nextInputType(). This information is not required to properly
+ * decode a frame.
+ *
+ * == Special case: skippable frames ==
+ *
+ * Skippable frames allow integration of user-defined data into a flow of
+ * concatenated frames. Skippable frames will be ignored (skipped) by a
+ * decompressor. The format of skippable frames is as follows:
+ * 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.
+ * Note: If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might
+ * actually be a zstd encoded frame with no content. For purposes of
+ * decompression, it is valid in both cases to skip the frame using
+ * ZSTD_findFrameCompressedSize() to find its size in bytes.
+ * It also returns frame size as fparamsPtr->frameContentSize.
+ ******************************************************************************/
+
+/*===== Buffer-less streaming decompression functions =====*/
+size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx);
+size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict,
+ size_t dictSize);
+void ZSTD_copyDCtx(ZSTD_DCtx *dctx, const ZSTD_DCtx *preparedDCtx);
+size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx);
+size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+typedef enum {
+ ZSTDnit_frameHeader,
+ ZSTDnit_blockHeader,
+ ZSTDnit_block,
+ ZSTDnit_lastBlock,
+ ZSTDnit_checksum,
+ ZSTDnit_skippableFrame
+} ZSTD_nextInputType_e;
+ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx);
+
+/*-*****************************************************************************
+ * Block functions
+ *
+ * Block functions produce and decode raw zstd blocks, without frame metadata.
+ * Frame metadata cost is typically ~18 bytes, which can be non-negligible for
+ * very small blocks (< 100 bytes). User will have to take in charge required
+ * information to regenerate data, such as compressed and content sizes.
+ *
+ * A few rules to respect:
+ * - Compressing and decompressing require a context structure
+ * + Use ZSTD_initCCtx() and ZSTD_initDCtx()
+ * - It is necessary to init context before starting
+ * + compression : ZSTD_compressBegin()
+ * + decompression : ZSTD_decompressBegin()
+ * + variants _usingDict() are also allowed
+ * + copyCCtx() and copyDCtx() work too
+ * - Block size is limited, it must be <= ZSTD_getBlockSizeMax()
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+
+ ip += headerSize;
+ remainingSize -= headerSize;
+
+ /* Loop on each block */
+ while (1) {
+ blockProperties_t blockProperties;
+ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
+ if (ZSTD_isError(cBlockSize))
+ return cBlockSize;
+
+ if (ZSTD_blockHeaderSize + cBlockSize > remainingSize)
+ return ERROR(srcSize_wrong);
+
+ ip += ZSTD_blockHeaderSize + cBlockSize;
+ remainingSize -= ZSTD_blockHeaderSize + cBlockSize;
+
+ if (blockProperties.lastBlock)
+ break;
+ }
+
+ if (fParams.checksumFlag) { /* Frame content checksum */
+ if (remainingSize < 4)
+ return ERROR(srcSize_wrong);
+ ip += 4;
+ remainingSize -= 4;
+ }
+
+ return ip - ipstart;
+ }
+}
+
+/*! ZSTD_decompressFrame() :
+* @dctx must be properly initialized */
+static size_t ZSTD_decompressFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void **srcPtr, size_t *srcSizePtr)
+{
+ const BYTE *ip = (const BYTE *)(*srcPtr);
+ BYTE *const ostart = (BYTE * const)dst;
+ BYTE *const oend = ostart + dstCapacity;
+ BYTE *op = ostart;
+ size_t remainingSize = *srcSizePtr;
+
+ /* check */
+ if (remainingSize < ZSTD_frameHeaderSize_min + ZSTD_blockHeaderSize)
+ return ERROR(srcSize_wrong);
+
+ /* Frame Header */
+ {
+ size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix);
+ if (ZSTD_isError(frameHeaderSize))
+ return frameHeaderSize;
+ if (remainingSize < frameHeaderSize + ZSTD_blockHeaderSize)
+ return ERROR(srcSize_wrong);
+ CHECK_F(ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize));
+ ip += frameHeaderSize;
+ remainingSize -= frameHeaderSize;
+ }
+
+ /* Loop on each block */
+ while (1) {
+ size_t decodedSize;
+ blockProperties_t blockProperties;
+ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
+ if (ZSTD_isError(cBlockSize))
+ return cBlockSize;
+
+ ip += ZSTD_blockHeaderSize;
+ remainingSize -= ZSTD_blockHeaderSize;
+ if (cBlockSize > remainingSize)
+ return ERROR(srcSize_wrong);
+
+ switch (blockProperties.blockType) {
+ case bt_compressed: decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend - op, ip, cBlockSize); break;
+ case bt_raw: decodedSize = ZSTD_copyRawBlock(op, oend - op, ip, cBlockSize); break;
+ case bt_rle: decodedSize = ZSTD_generateNxBytes(op, oend - op, *ip, blockProperties.origSize); break;
+ case bt_reserved:
+ default: return ERROR(corruption_detected);
+ }
+
+ if (ZSTD_isError(decodedSize))
+ return decodedSize;
+ if (dctx->fParams.checksumFlag)
+ xxh64_update(&dctx->xxhState, op, decodedSize);
+ op += decodedSize;
+ ip += cBlockSize;
+ remainingSize -= cBlockSize;
+ if (blockProperties.lastBlock)
+ break;
+ }
+
+ if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */
+ U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState);
+ U32 checkRead;
+ if (remainingSize < 4)
+ return ERROR(checksum_wrong);
+ checkRead = ZSTD_readLE32(ip);
+ if (checkRead != checkCalc)
+ return ERROR(checksum_wrong);
+ ip += 4;
+ remainingSize -= 4;
+ }
+
+ /* Allow caller to get size read */
+ *srcPtr = ip;
+ *srcSizePtr = remainingSize;
+ return op - ostart;
+}
+
+static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict);
+static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict);
+
+static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize,
+ const ZSTD_DDict *ddict)
+{
+ void *const dststart = dst;
+
+ if (ddict) {
+ if (dict) {
+ /* programmer error, these two cases should be mutually exclusive */
+ return ERROR(GENERIC);
+ }
+
+ dict = ZSTD_DDictDictContent(ddict);
+ dictSize = ZSTD_DDictDictSize(ddict);
+ }
+
+ while (srcSize >= ZSTD_frameHeaderSize_prefix) {
+ U32 magicNumber;
+
+ magicNumber = ZSTD_readLE32(src);
+ if (magicNumber != ZSTD_MAGICNUMBER) {
+ if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
+ size_t skippableSize;
+ if (srcSize < ZSTD_skippableHeaderSize)
+ return ERROR(srcSize_wrong);
+ skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize;
+ if (srcSize < skippableSize) {
+ return ERROR(srcSize_wrong);
+ }
+
+ src = (const BYTE *)src + skippableSize;
+ srcSize -= skippableSize;
+ continue;
+ } else {
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ {
+ size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict);
+ if (ZSTD_isError(errorCode)) {
+ ZSTD_freeDDict(ddict);
+ return NULL;
+ }
+ }
+
+ return ddict;
+ }
+}
+
+/*! ZSTD_initDDict() :
+* Create a digested dictionary, to start decompression without startup delay.
+* `dict` content is copied inside DDict.
+* Consequently, `dict` can be released after `ZSTD_DDict` creation */
+ZSTD_DDict *ZSTD_initDDict(const void *dict, size_t dictSize, void *workspace, size_t workspaceSize)
+{
+ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
+ return ZSTD_createDDict_advanced(dict, dictSize, 1, stackMem);
+}
+
+size_t ZSTD_freeDDict(ZSTD_DDict *ddict)
+{
+ if (ddict == NULL)
+ return 0; /* support free on NULL */
+ {
+ ZSTD_customMem const cMem = ddict->cMem;
+ ZSTD_free(ddict->dictBuffer, cMem);
+ ZSTD_free(ddict, cMem);
+ return 0;
+ }
+}
+
+/*! ZSTD_getDictID_fromDict() :
+ * Provides the dictID stored within dictionary.
+ * if @return == 0, the dictionary is not conformant with Zstandard specification.
+ * It can still be loaded, but as a content-only dictionary. */
+unsigned ZSTD_getDictID_fromDict(const void *dict, size_t dictSize)
+{
+ if (dictSize < 8)
+ return 0;
+ if (ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC)
+ return 0;
+ return ZSTD_readLE32((const char *)dict + 4);
+}
+
+/*! ZSTD_getDictID_fromDDict() :
+ * Provides the dictID of the dictionary loaded into `ddict`.
+ * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
+ * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
+unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict)
+{
+ if (ddict == NULL)
+ return 0;
+ return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize);
+}
+
+/*! ZSTD_getDictID_fromFrame() :
+ * Provides the dictID required to decompressed the frame stored within `src`.
+ * If @return == 0, the dictID could not be decoded.
+ * This could for one of the following reasons :
+ * - The frame does not require a dictionary to be decoded (most common case).
+ * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information.
+ * Note : this use case also happens when using a non-conformant dictionary.
+ * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`).
+ * - This is not a Zstandard frame.
+ * When identifying the exact failure cause, it's possible to used ZSTD_getFrameParams(), which will provide a more precise error code. */
+unsigned ZSTD_getDictID_fromFrame(const void *src, size_t srcSize)
+{
+ ZSTD_frameParams zfp = {0, 0, 0, 0};
+ size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize);
+ if (ZSTD_isError(hError))
+ return 0;
+ return zfp.dictID;
+}
+
+/*! ZSTD_decompress_usingDDict() :
+* Decompression using a pre-digested Dictionary
+* Use dictionary without significant overhead. */
+size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_DDict *ddict)
+{
+ /* pass content and size in case legacy frames are encountered */
+ return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, NULL, 0, ddict);
+}
+
+/*=====================================
+* Streaming decompression
+*====================================*/
+
+typedef enum { zdss_init, zdss_loadHeader, zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
+
+/* *** Resource management *** */
+struct ZSTD_DStream_s {
+ ZSTD_DCtx *dctx;
+ ZSTD_DDict *ddictLocal;
+ const ZSTD_DDict *ddict;
+ ZSTD_frameParams fParams;
+ ZSTD_dStreamStage stage;
+ char *inBuff;
+ size_t inBuffSize;
+ size_t inPos;
+ size_t maxWindowSize;
+ char *outBuff;
+ size_t outBuffSize;
+ size_t outStart;
+ size_t outEnd;
+ size_t blockSize;
+ BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; /* tmp buffer to store frame header */
+ size_t lhSize;
+ ZSTD_customMem customMem;
+ void *legacyContext;
+ U32 previousLegacyVersion;
+ U32 legacyVersion;
+ U32 hostageByte;
+}; /* typedef'd to ZSTD_DStream within "zstd.h" */
+
+size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize)
+{
+ size_t const blockSize = MIN(maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
+ size_t const inBuffSize = blockSize;
+ size_t const outBuffSize = maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
+ return ZSTD_DCtxWorkspaceBound() + ZSTD_ALIGN(sizeof(ZSTD_DStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize);
+}
+
+static ZSTD_DStream *ZSTD_createDStream_advanced(ZSTD_customMem customMem)
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ break;
+ }
+
+ /* check for single-pass mode opportunity */
+ if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */
+ && (U64)(size_t)(oend - op) >= zds->fParams.frameContentSize) {
+ size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend - istart);
+ if (cSize <= (size_t)(iend - istart)) {
+ size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend - op, istart, cSize, zds->ddict);
+ if (ZSTD_isError(decompressedSize))
+ return decompressedSize;
+ ip = istart + cSize;
+ op += decompressedSize;
+ zds->dctx->expected = 0;
+ zds->stage = zdss_init;
+ someMoreWork = 0;
+ break;
+ }
+ }
+
+ /* Consume header */
+ ZSTD_refDDict(zds->dctx, zds->ddict);
+ {
+ size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); /* == ZSTD_frameHeaderSize_prefix */
+ CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size));
+ {
+ size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+ CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer + h1Size, h2Size));
+ }
+ }
+
+ zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
+ if (zds->fParams.windowSize > zds->maxWindowSize)
+ return ERROR(frameParameter_windowTooLarge);
+
+ /* Buffers are preallocated, but double check */
+ {
+ size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
+ size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
+ if (zds->inBuffSize < blockSize) {
+ return ERROR(GENERIC);
+ }
+ if (zds->outBuffSize < neededOutSize) {
+ return ERROR(GENERIC);
+ }
+ zds->blockSize = blockSize;
+ }
+ zds->stage = zdss_read;
+ }
+ /* pass-through */
+
+ case zdss_read: {
+ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+ if (neededInSize == 0) { /* end of frame */
+ zds->stage = zdss_init;
+ someMoreWork = 0;
+ break;
+ }
+ if ((size_t)(iend - ip) >= neededInSize) { /* decode directly from src */
+ const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
+ size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart,
+ (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), ip, neededInSize);
+ if (ZSTD_isError(decodedSize))
+ return decodedSize;
+ ip += neededInSize;
+ if (!decodedSize && !isSkipFrame)
+ break; /* this was just a header */
+ zds->outEnd = zds->outStart + decodedSize;
+ zds->stage = zdss_flush;
+ break;
+ }
+ if (ip == iend) {
+ someMoreWork = 0;
+ break;
+ } /* no more input */
+ zds->stage = zdss_load;
+ /* pass-through */
+ }
+
+ case zdss_load: {
+ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+ size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */
+ size_t loadedSize;
+ if (toLoad > zds->inBuffSize - zds->inPos)
+ return ERROR(corruption_detected); /* should never happen */
+ loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend - ip);
+ ip += loadedSize;
+ zds->inPos += loadedSize;
+ if (loadedSize < toLoad) {
+ someMoreWork = 0;
+ break;
+ } /* not enough input, wait for more */
+
+ /* decode loaded input */
+ {
+ const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
+ size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart,
+ zds->inBuff, neededInSize);
+ if (ZSTD_isError(decodedSize))
+ return decodedSize;
+ zds->inPos = 0; /* input is consumed */
+ if (!decodedSize && !isSkipFrame) {
+ zds->stage = zdss_read;
+ break;
+ } /* this was just a header */
+ zds->outEnd = zds->outStart + decodedSize;
+ zds->stage = zdss_flush;
+ /* pass-through */
+ }
+ }
+
+ case zdss_flush: {
+ size_t const toFlushSize = zds->outEnd - zds->outStart;
+ size_t const flushedSize = ZSTD_limitCopy(op, oend - op, zds->outBuff + zds->outStart, toFlushSize);
+ op += flushedSize;
+ zds->outStart += flushedSize;
+ if (flushedSize == toFlushSize) { /* flush completed */
+ zds->stage = zdss_read;
+ if (zds->outStart + zds->blockSize > zds->outBuffSize)
+ zds->outStart = zds->outEnd = 0;
+ break;
+ }
+ /* cannot complete flush */
+ someMoreWork = 0;
+ break;
+ }
+ default:
+ return ERROR(GENERIC); /* impossible */
+ }
+ }
+
+ /* result */
+ input->pos += (size_t)(ip - istart);
+ output->pos += (size_t)(op - ostart);
+ {
+ size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+ if (!nextSrcSizeHint) { /* frame fully decoded */
+ if (zds->outEnd == zds->outStart) { /* output fully flushed */
+ if (zds->hostageByte) {
+ if (input->pos >= input->size) {
+ zds->stage = zdss_read;
+ return 1;
+ } /* can't release hostage (not present) */
+ input->pos++; /* release hostage */
+ }
+ return 0;
+ }
+ if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */
+ input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */
+ zds->hostageByte = 1;
+ }
+ return 1;
+ }
+ nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block); /* preload header of next block */
+ if (zds->inPos > nextSrcSizeHint)
+ return ERROR(GENERIC); /* should never happen */
+ nextSrcSizeHint -= zds->inPos; /* already loaded*/
+ return nextSrcSizeHint;
+ }
+}
+
+EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound);
+EXPORT_SYMBOL(ZSTD_initDCtx);
+EXPORT_SYMBOL(ZSTD_decompressDCtx);
+EXPORT_SYMBOL(ZSTD_decompress_usingDict);
+
+EXPORT_SYMBOL(ZSTD_DDictWorkspaceBound);
+EXPORT_SYMBOL(ZSTD_initDDict);
+EXPORT_SYMBOL(ZSTD_decompress_usingDDict);
+
+EXPORT_SYMBOL(ZSTD_DStreamWorkspaceBound);
+EXPORT_SYMBOL(ZSTD_initDStream);
+EXPORT_SYMBOL(ZSTD_initDStream_usingDDict);
+EXPORT_SYMBOL(ZSTD_resetDStream);
+EXPORT_SYMBOL(ZSTD_decompressStream);
+EXPORT_SYMBOL(ZSTD_DStreamInSize);
+EXPORT_SYMBOL(ZSTD_DStreamOutSize);
+
+EXPORT_SYMBOL(ZSTD_findFrameCompressedSize);
+EXPORT_SYMBOL(ZSTD_getFrameContentSize);
+EXPORT_SYMBOL(ZSTD_findDecompressedSize);
+
+EXPORT_SYMBOL(ZSTD_isFrame);
+EXPORT_SYMBOL(ZSTD_getDictID_fromDict);
+EXPORT_SYMBOL(ZSTD_getDictID_fromDDict);
+EXPORT_SYMBOL(ZSTD_getDictID_fromFrame);
+
+EXPORT_SYMBOL(ZSTD_getFrameParams);
+EXPORT_SYMBOL(ZSTD_decompressBegin);
+EXPORT_SYMBOL(ZSTD_decompressBegin_usingDict);
+EXPORT_SYMBOL(ZSTD_copyDCtx);
+EXPORT_SYMBOL(ZSTD_nextSrcSizeToDecompress);
+EXPORT_SYMBOL(ZSTD_decompressContinue);
+EXPORT_SYMBOL(ZSTD_nextInputType);
+
+EXPORT_SYMBOL(ZSTD_decompressBlock);
+EXPORT_SYMBOL(ZSTD_insertBlock);
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ threshold >>= 1;
+ }
+
+ if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) {
+ ip += bitCount >> 3;
+ bitCount &= 7;
+ } else {
+ bitCount -= (int)(8 * (iend - 4 - ip));
+ ip = iend - 4;
+ }
+ bitStream = ZSTD_readLE32(ip) >> (bitCount & 31);
+ }
+ } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */
+ if (remaining != 1)
+ return ERROR(corruption_detected);
+ if (bitCount > 32)
+ return ERROR(corruption_detected);
+ *maxSVPtr = charnum - 1;
+
+ ip += (bitCount + 7) >> 3;
+ return ip - istart;
+}
+
+/*! HUF_readStats() :
+ Read compact Huffman tree, saved by HUF_writeCTable().
+ `huffWeight` is destination buffer.
+ `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32.
+ @return : size read from `src` , or an error Code .
+ Note : Needed by HUF_readCTable() and HUF_readDTableX?() .
+*/
+size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
+{
+ U32 weightTotal;
+ const BYTE *ip = (const BYTE *)src;
+ size_t iSize;
+ size_t oSize;
+
+ if (!srcSize)
+ return ERROR(srcSize_wrong);
+ iSize = ip[0];
+ /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */
+
+ if (iSize >= 128) { /* special header */
+ oSize = iSize - 127;
+ iSize = ((oSize + 1) / 2);
+ if (iSize + 1 > srcSize)
+ return ERROR(srcSize_wrong);
+ if (oSize >= hwSize)
+ return ERROR(corruption_detected);
+ ip += 1;
+ {
+ U32 n;
+ for (n = 0; n < oSize; n += 2) {
+ huffWeight[n] = ip[n / 2] >> 4;
+ huffWeight[n + 1] = ip[n / 2] & 15;
+ }
+ }
+ } else { /* header compressed with FSE (normal case) */
+ if (iSize + 1 > srcSize)
+ return ERROR(srcSize_wrong);
+ oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */
+ if (FSE_isError(oSize))
+ return oSize;
+ }
+
+ /* collect weight stats */
+ memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
+ weightTotal = 0;
+ {
+ U32 n;
+ for (n = 0; n < oSize; n++) {
+ if (huffWeight[n] >= HUF_TABLELOG_MAX)
+ return ERROR(corruption_detected);
+ rankStats[huffWeight[n]]++;
+ weightTotal += (1 << huffWeight[n]) >> 1;
+ }
+ }
+ if (weightTotal == 0)
+ return ERROR(corruption_detected);
+
+ /* get last non-null symbol weight (implied, total must be 2^n) */
+ {
+ U32 const tableLog = BIT_highbit32(weightTotal) + 1;
+ if (tableLog > HUF_TABLELOG_MAX)
+ return ERROR(corruption_detected);
+ *tableLogPtr = tableLog;
+ /* determine last weight */
+ {
+ U32 const total = 1 << tableLog;
+ U32 const rest = total - weightTotal;
+ U32 const verif = 1 << BIT_highbit32(rest);
+ U32 const lastWeight = BIT_highbit32(rest) + 1;
+ if (verif != rest)
+ return ERROR(corruption_detected); /* last value must be a clean power of 2 */
+ huffWeight[oSize] = (BYTE)lastWeight;
+ rankStats[lastWeight]++;
+ }
+ }
+
+ /* check tree construction validity */
+ if ((rankStats[1] < 2) || (rankStats[1] & 1))
+ return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */
+
+ /* results */
+ *nbSymbolsPtr = (U32)(oSize + 1);
+ return iSize + 1;
+}
diff --git a/lib/zstd/error_private.h b/lib/zstd/error_private.h
new file mode 100644
index 0000000..2062ff0
--- /dev/null
+++ b/lib/zstd/error_private.h
@@ -0,0 +1,51 @@
+/**
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of https://github.com/facebook/zstd.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+
+Note that BIT_initCStream() can produce an error code, so its result should be tested, using FSE_isError();
+You can then encode your input data, byte after byte.
+FSE_encodeSymbol() outputs a maximum of 'tableLog' bits at a time.
+Remember decoding will be done in reverse direction.
+ FSE_encodeByte(&bitStream, &state, symbol);
+
+At any time, you can also add any bit sequence.
+Note : maximum allowed nbBits is 25, for compatibility with 32-bits decoders
+ BIT_addBits(&bitStream, bitField, nbBits);
+
+The above methods don't commit data to memory, they just store it into local register, for speed.
+Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
+Writing data to memory is a manual operation, performed by the flushBits function.
+ BIT_flushBits(&bitStream);
+
+Your last FSE encoding operation shall be to flush your last state value(s).
+ FSE_flushState(&bitStream, &state);
+
+Finally, you must close the bitStream.
+The function returns the size of CStream in bytes.
+If data couldn't fit into dstBuffer, it will return a 0 ( == not compressible)
+If there is an error, it returns an errorCode (which can be tested using FSE_isError()).
+ size_t size = BIT_closeCStream(&bitStream);
+*/
+
+/* *****************************************
+* FSE symbol decompression API
+*******************************************/
+typedef struct {
+ size_t state;
+ const void *table; /* precise table may vary, depending on U16 */
+} FSE_DState_t;
+
+static void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt);
+
+static unsigned char FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
+
+static unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr);
+
+/**<
+Let's now decompose FSE_decompress_usingDTable() into its unitary components.
+You will decode FSE-encoded symbols from the bitStream,
+and also any other bitFields you put in, **in reverse order**.
+
+You will need a few variables to track your bitStream. They are :
+
+BIT_DStream_t DStream; // Stream context
+FSE_DState_t DState; // State context. Multiple ones are possible
+FSE_DTable* DTablePtr; // Decoding table, provided by FSE_buildDTable()
+
+The first thing to do is to init the bitStream.
+ errorCode = BIT_initDStream(&DStream, srcBuffer, srcSize);
+
+You should then retrieve your initial state(s)
+(in reverse flushing order if you have several ones) :
+ errorCode = FSE_initDState(&DState, &DStream, DTablePtr);
+
+You can then decode your data, symbol after symbol.
+For information the maximum number of bits read by FSE_decodeSymbol() is 'tableLog'.
+Keep in mind that symbols are decoded in reverse order, like a LIFO stack (last in, first out).
+ unsigned char symbol = FSE_decodeSymbol(&DState, &DStream);
+
+You can retrieve any bitfield you eventually stored into the bitStream (in reverse order)
+Note : maximum allowed nbBits is 25, for 32-bits compatibility
+ size_t bitField = BIT_readBits(&DStream, nbBits);
+
+All above operations only read from local register (which size depends on size_t).
+Refueling the register from memory is manually performed by the reload method.
+ endSignal = FSE_reloadDStream(&DStream);
+
+BIT_reloadDStream() result tells if there is still some more data to read from DStream.
+BIT_DStream_unfinished : there is still some data left into the DStream.
+BIT_DStream_endOfBuffer : Dstream reached end of buffer. Its container may no longer be completely filled.
+BIT_DStream_completed : Dstream reached its exact end, corresponding in general to decompression completed.
+BIT_DStream_tooFar : Dstream went too far. Decompression result is corrupted.
+
+When reaching end of buffer (BIT_DStream_endOfBuffer), progress slowly, notably if you decode multiple symbols per loop,
+to properly detect the exact end of stream.
+After each decoded symbol, check if DStream is fully consumed using this simple test :
+ BIT_reloadDStream(&DStream) >= BIT_DStream_completed
+
+When it's done, verify decompression is fully completed, by checking both DStream and the relevant states.
+Checking if DStream has reached its end is performed by :
+ BIT_endOfDStream(&DStream);
+Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible.
+ FSE_endOfDState(&DState);
+*/
+
+/* *****************************************
+* FSE unsafe API
+*******************************************/
+static unsigned char FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
+/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
+
+/* *****************************************
+* Implementation of inlined functions
+*******************************************/
+typedef struct {
+ int deltaFindState;
+ U32 deltaNbBits;
+} FSE_symbolCompressionTransform; /* total 8 bytes */
+
+ZSTD_STATIC void FSE_initCState(FSE_CState_t *statePtr, const FSE_CTable *ct)
+{
+ const void *ptr = ct;
+ const U16 *u16ptr = (const U16 *)ptr;
+ const U32 tableLog = ZSTD_read16(ptr);
+ statePtr->value = (ptrdiff_t)1 << tableLog;
+ statePtr->stateTable = u16ptr + 2;
+ statePtr->symbolTT = ((const U32 *)ct + 1 + (tableLog ? (1 << (tableLog - 1)) : 1));
+ statePtr->stateLog = tableLog;
+}
+
+/*! FSE_initCState2() :
+* Same as FSE_initCState(), but the first symbol to include (which will be the last to be read)
+* uses the smallest state value possible, saving the cost of this symbol */
+ZSTD_STATIC void FSE_initCState2(FSE_CState_t *statePtr, const FSE_CTable *ct, U32 symbol)
+{
+ FSE_initCState(statePtr, ct);
+ {
+ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
+ const U16 *stateTable = (const U16 *)(statePtr->stateTable);
+ U32 nbBitsOut = (U32)((symbolTT.deltaNbBits + (1 << 15)) >> 16);
+ statePtr->value = (nbBitsOut << 16) - symbolTT.deltaNbBits;
+ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
+ }
+}
+
+ZSTD_STATIC void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *statePtr, U32 symbol)
+{
+ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
+ const U16 *const stateTable = (const U16 *)(statePtr->stateTable);
+ U32 nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16);
+ BIT_addBits(bitC, statePtr->value, nbBitsOut);
+ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
+}
+
+ZSTD_STATIC void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *statePtr)
+{
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* 16-32 symbols per loop (4-8 symbols per stream) */
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) {
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ }
+
+ /* check corruption */
+ if (op1 > opStart2)
+ return ERROR(corruption_detected);
+ if (op2 > opStart3)
+ return ERROR(corruption_detected);
+ if (op3 > opStart4)
+ return ERROR(corruption_detected);
+ /* note : op4 supposed already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endSignal)
+ return ERROR(corruption_detected);
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 0)
+ return ERROR(GENERIC);
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
+}
+
+/* *************************/
+/* double-symbols decoding */
+/* *************************/
+typedef struct {
+ U16 sequence;
+ BYTE nbBits;
+ BYTE length;
+} HUF_DEltX4; /* double-symbols decoding */
+
+typedef struct {
+ BYTE symbol;
+ BYTE weight;
+} sortedSymbol_t;
+
+/* HUF_fillDTableX4Level2() :
+ * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
+static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight,
+ const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq)
+{
+ HUF_DEltX4 DElt;
+ U32 rankVal[HUF_TABLELOG_MAX + 1];
+
+ /* get pre-calculated rankVal */
+ memcpy(rankVal, rankValOrigin, sizeof(rankVal));
+
+ /* fill skipped values */
+ if (minWeight > 1) {
+ U32 i, skipSize = rankVal[minWeight];
+ ZSTD_writeLE16(&(DElt.sequence), baseSeq);
+ DElt.nbBits = (BYTE)(consumed);
+ DElt.length = 1;
+ for (i = 0; i < skipSize; i++)
+ DTable[i] = DElt;
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \
+ if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \
+ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \
+ if (ZSTD_64bits()) \
+ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog)
+{
+ BYTE *const pStart = p;
+
+ /* up to 8 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) {
+ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
+ }
+
+ /* closer to end : up to 2 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2))
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
+
+ while (p <= pEnd - 2)
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
+
+ if (p < pEnd)
+ p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog);
+
+ return p - pStart;
+}
+
+static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ BIT_DStream_t bitD;
+
+ /* Init */
+ {
+ size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* decode */
+ {
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *const oend = ostart + dstSize;
+ const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */
+ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog);
+ }
+
+ /* check */
+ if (!BIT_endOfDStream(&bitD))
+ return ERROR(corruption_detected);
+
+ /* decoded size */
+ return dstSize;
+}
+
+size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1)
+ return ERROR(GENERIC);
+ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx);
+}
+
+static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ if (cSrcSize < 10)
+ return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
+
+ {
+ const BYTE *const istart = (const BYTE *)cSrc;
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *const oend = ostart + dstSize;
+ const void *const dtPtr = DTable + 1;
+ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
+
+ /* Init */
+ BIT_DStream_t bitD1;
+ BIT_DStream_t bitD2;
+ BIT_DStream_t bitD3;
+ BIT_DStream_t bitD4;
+ size_t const length1 = ZSTD_readLE16(istart);
+ size_t const length2 = ZSTD_readLE16(istart + 2);
+ size_t const length3 = ZSTD_readLE16(istart + 4);
+ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
+ const BYTE *const istart1 = istart + 6; /* jumpTable */
+ const BYTE *const istart2 = istart1 + length1;
+ const BYTE *const istart3 = istart2 + length2;
+ const BYTE *const istart4 = istart3 + length3;
+ size_t const segmentSize = (dstSize + 3) / 4;
+ BYTE *const opStart2 = ostart + segmentSize;
+ BYTE *const opStart3 = opStart2 + segmentSize;
+ BYTE *const opStart4 = opStart3 + segmentSize;
+ BYTE *op1 = ostart;
+ BYTE *op2 = opStart2;
+ BYTE *op3 = opStart3;
+ BYTE *op4 = opStart4;
+ U32 endSignal;
ext/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch view on Meta::CPAN
+ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* 16-32 symbols per loop (4-8 symbols per stream) */
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) {
+ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_0(op4, &bitD4);
+
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ }
+
+ /* check corruption */
+ if (op1 > opStart2)
+ return ERROR(corruption_detected);
+ if (op2 > opStart3)
+ return ERROR(corruption_detected);
+ if (op3 > opStart4)
+ return ERROR(corruption_detected);
+ /* note : op4 already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ {
+ U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endCheck)
+ return ERROR(corruption_detected);
+ }
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1)
+ return ERROR(GENERIC);
+ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
+}
+
+/* ********************************/
+/* Generic decompression selector */
+/* ********************************/
+
+size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
+ : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
+ : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
+}
+
+typedef struct {
+ U32 tableTime;
+ U32 decode256Time;
+} algo_time_t;
+static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = {
+ /* single, double, quad */
+ {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */
+ {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */
+ {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */
+ {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */
+ {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */
+ {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */
+ {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */
+ {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */
+ {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */
( run in 1.347 second using v1.01-cache-2.11-cpan-39bf76dae61 )