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https://github.com/facebook/zstd.git
synced 2025-03-06 08:49:28 +02:00
added constant ZSTD_MAGIC_SKIPPABLE_MASK
and updated several API comments
This commit is contained in:
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@ -20,16 +20,17 @@
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<li><a href="#Chapter10">Streaming decompression - HowTo</a></li>
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<li><a href="#Chapter11">ADVANCED AND EXPERIMENTAL FUNCTIONS</a></li>
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<li><a href="#Chapter12">Candidate API for promotion into stable</a></li>
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<li><a href="#Chapter13">Frame size functions</a></li>
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<li><a href="#Chapter14">Memory management</a></li>
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<li><a href="#Chapter15">Advanced compression functions</a></li>
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<li><a href="#Chapter16">Advanced decompression functions</a></li>
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<li><a href="#Chapter17">Advanced streaming functions</a></li>
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<li><a href="#Chapter18">Buffer-less and synchronous inner streaming functions</a></li>
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<li><a href="#Chapter19">Buffer-less streaming compression (synchronous mode)</a></li>
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<li><a href="#Chapter20">Buffer-less streaming decompression (synchronous mode)</a></li>
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<li><a href="#Chapter21">New advanced API (experimental)</a></li>
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<li><a href="#Chapter22">Block level API</a></li>
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<li><a href="#Chapter13">Purely experimental API</a></li>
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<li><a href="#Chapter14">Frame size functions</a></li>
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<li><a href="#Chapter15">Memory management</a></li>
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<li><a href="#Chapter16">Advanced compression functions</a></li>
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<li><a href="#Chapter17">Advanced decompression functions</a></li>
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<li><a href="#Chapter18">Advanced streaming functions</a></li>
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<li><a href="#Chapter19">Buffer-less and synchronous inner streaming functions</a></li>
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<li><a href="#Chapter20">Buffer-less streaming compression (synchronous mode)</a></li>
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<li><a href="#Chapter21">Buffer-less streaming decompression (synchronous mode)</a></li>
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<li><a href="#Chapter22">New advanced API (experimental)</a></li>
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<li><a href="#Chapter23">Block level API</a></li>
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</ol>
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<hr>
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<a name="Chapter1"></a><h2>Introduction</h2><pre>
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@ -356,23 +357,38 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
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<pre><b>int ZSTD_minCLevel(void); </b>/*!< minimum negative compression level allowed */<b>
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</b></pre><BR>
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<pre><b>typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
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ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy; </b>/* from faster to stronger */<b>
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<a name="Chapter13"></a><h2>Purely experimental API</h2><pre>
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The following symbols and constants are not planned
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to join "stable API" status anytime soon.
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Some of them might even be removed in the future.
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<BR></pre>
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<pre><b>typedef enum { ZSTD_fast=1,
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ZSTD_dfast=2,
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ZSTD_greedy=3,
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ZSTD_lazy=4,
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ZSTD_lazy2=5,
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ZSTD_btlazy2=6,
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ZSTD_btopt=7,
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ZSTD_btultra=8
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</b>/* note : new strategies might be added in the future */<b>
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} ZSTD_strategy;
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</b></pre><BR>
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<pre><b>typedef struct {
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unsigned windowLog; </b>/**< largest match distance : larger == more compression, more memory needed during decompression */<b>
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unsigned chainLog; </b>/**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */<b>
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unsigned hashLog; </b>/**< dispatch table : larger == faster, more memory */<b>
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unsigned searchLog; </b>/**< nb of searches : larger == more compression, slower */<b>
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unsigned searchLength; </b>/**< match length searched : larger == faster decompression, sometimes less compression */<b>
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unsigned targetLength; </b>/**< acceptable match size for optimal parser (only) : larger == more compression, slower */<b>
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ZSTD_strategy strategy;
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unsigned windowLog; </b>/**< largest match distance : larger == more compression, more memory needed during decompression */<b>
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unsigned chainLog; </b>/**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */<b>
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unsigned hashLog; </b>/**< dispatch table : larger == faster, more memory */<b>
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unsigned searchLog; </b>/**< nb of searches : larger == more compression, slower */<b>
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unsigned searchLength; </b>/**< match length searched : larger == faster decompression, sometimes less compression */<b>
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unsigned targetLength; </b>/**< acceptable match size for optimal parser (only) : larger == more compression, slower */<b>
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ZSTD_strategy strategy; </b>/**< see ZSTD_strategy definition above */<b>
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} ZSTD_compressionParameters;
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</b></pre><BR>
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<pre><b>typedef struct {
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unsigned contentSizeFlag; </b>/**< 1: content size will be in frame header (when known) */<b>
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unsigned checksumFlag; </b>/**< 1: generate a 32-bits checksum at end of frame, for error detection */<b>
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unsigned noDictIDFlag; </b>/**< 1: no dictID will be saved into frame header (if dictionary compression) */<b>
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unsigned checksumFlag; </b>/**< 1: generate a 32-bits checksum using XXH64 algorithm at end of frame, for error detection */<b>
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unsigned noDictIDFlag; </b>/**< 1: no dictID will be saved into frame header (dictID is only useful for dictionary compression) */<b>
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} ZSTD_frameParameters;
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</b></pre><BR>
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<pre><b>typedef struct {
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@ -381,17 +397,17 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
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} ZSTD_parameters;
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</b></pre><BR>
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<pre><b>typedef enum {
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ZSTD_dct_auto = 0, </b>/* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */<b>
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ZSTD_dct_rawContent, </b>/* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */<b>
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ZSTD_dct_fullDict </b>/* refuses to load a dictionary if it does not respect Zstandard's specification */<b>
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ZSTD_dct_auto = 0, </b>/* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */<b>
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ZSTD_dct_rawContent = 1, </b>/* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */<b>
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ZSTD_dct_fullDict = 2 </b>/* refuses to load a dictionary if it does not respect Zstandard's specification, starting with ZSTD_MAGIC_DICTIONARY */<b>
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} ZSTD_dictContentType_e;
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</b></pre><BR>
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<pre><b>typedef enum {
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ZSTD_dlm_byCopy = 0, </b>/**< Copy dictionary content internally */<b>
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ZSTD_dlm_byRef, </b>/**< Reference dictionary content -- the dictionary buffer must outlive its users. */<b>
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ZSTD_dlm_byCopy = 0, </b>/**< Copy dictionary content internally */<b>
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ZSTD_dlm_byRef = 1, </b>/**< Reference dictionary content -- the dictionary buffer must outlive its users. */<b>
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} ZSTD_dictLoadMethod_e;
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</b></pre><BR>
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<a name="Chapter13"></a><h2>Frame size functions</h2><pre></pre>
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<a name="Chapter14"></a><h2>Frame size functions</h2><pre></pre>
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<pre><b>size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize);
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</b><p> `src` should point to the start of a ZSTD encoded frame or skippable frame
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@ -430,7 +446,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
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or an error code (if srcSize is too small)
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</p></pre><BR>
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<a name="Chapter14"></a><h2>Memory management</h2><pre></pre>
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<a name="Chapter15"></a><h2>Memory management</h2><pre></pre>
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<pre><b>size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
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size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
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@ -520,7 +536,7 @@ static ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL }; </b>/**< t
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</p></pre><BR>
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<a name="Chapter15"></a><h2>Advanced compression functions</h2><pre></pre>
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<a name="Chapter16"></a><h2>Advanced compression functions</h2><pre></pre>
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<pre><b>ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);
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</b><p> Create a digested dictionary for compression
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@ -562,7 +578,7 @@ static ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL }; </b>/**< t
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</b><p> Same as ZSTD_compress_usingCDict(), with fine-tune control over frame parameters
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</p></pre><BR>
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<a name="Chapter16"></a><h2>Advanced decompression functions</h2><pre></pre>
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<a name="Chapter17"></a><h2>Advanced decompression functions</h2><pre></pre>
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<pre><b>unsigned ZSTD_isFrame(const void* buffer, size_t size);
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</b><p> Tells if the content of `buffer` starts with a valid Frame Identifier.
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@ -602,7 +618,7 @@ static ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL }; </b>/**< t
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When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code.
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</p></pre><BR>
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<a name="Chapter17"></a><h2>Advanced streaming functions</h2><pre></pre>
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<a name="Chapter18"></a><h2>Advanced streaming functions</h2><pre></pre>
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<h3>Advanced Streaming compression functions</h3><pre></pre><b><pre>size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize); </b>/**< pledgedSrcSize must be correct. If it is not known at init time, use ZSTD_CONTENTSIZE_UNKNOWN. Note that, for compatibility with older programs, "0" also disables frame content size field. It may be enabled in the future. */<b>
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size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); </b>/**< creates of an internal CDict (incompatible with static CCtx), except if dict == NULL or dictSize < 8, in which case no dict is used. Note: dict is loaded with ZSTD_dm_auto (treated as a full zstd dictionary if it begins with ZSTD_MAGIC_DICTIONARY, else as raw content) and ZSTD_dlm_byCopy.*/<b>
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@ -653,14 +669,14 @@ size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t di
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size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict); </b>/**< note : ddict is referenced, it must outlive decompression session */<b>
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size_t ZSTD_resetDStream(ZSTD_DStream* zds); </b>/**< re-use decompression parameters from previous init; saves dictionary loading */<b>
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</pre></b><BR>
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<a name="Chapter18"></a><h2>Buffer-less and synchronous inner streaming functions</h2><pre>
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<a name="Chapter19"></a><h2>Buffer-less and synchronous inner streaming functions</h2><pre>
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This is an advanced API, giving full control over buffer management, for users which need direct control over memory.
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But it's also a complex one, with several restrictions, documented below.
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Prefer normal streaming API for an easier experience.
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<BR></pre>
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<a name="Chapter19"></a><h2>Buffer-less streaming compression (synchronous mode)</h2><pre>
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<a name="Chapter20"></a><h2>Buffer-less streaming compression (synchronous mode)</h2><pre>
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A ZSTD_CCtx object is required to track streaming operations.
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Use ZSTD_createCCtx() / ZSTD_freeCCtx() to manage resource.
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ZSTD_CCtx object can be re-used multiple times within successive compression operations.
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@ -696,7 +712,7 @@ size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
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size_t ZSTD_compressBegin_usingCDict_advanced(ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict, ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize); </b>/* compression parameters are already set within cdict. pledgedSrcSize must be correct. If srcSize is not known, use macro ZSTD_CONTENTSIZE_UNKNOWN */<b>
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size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); </b>/**< note: if pledgedSrcSize is not known, use ZSTD_CONTENTSIZE_UNKNOWN */<b>
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</pre></b><BR>
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<a name="Chapter20"></a><h2>Buffer-less streaming decompression (synchronous mode)</h2><pre>
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<a name="Chapter21"></a><h2>Buffer-less streaming decompression (synchronous mode)</h2><pre>
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A ZSTD_DCtx object is required to track streaming operations.
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Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
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A ZSTD_DCtx object can be re-used multiple times.
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@ -787,7 +803,7 @@ size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long
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</pre></b><BR>
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<pre><b>typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
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</b></pre><BR>
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<a name="Chapter21"></a><h2>New advanced API (experimental)</h2><pre></pre>
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<a name="Chapter22"></a><h2>New advanced API (experimental)</h2><pre></pre>
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<pre><b>typedef enum {
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</b>/* Opened question : should we have a format ZSTD_f_auto ?<b>
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@ -1283,7 +1299,7 @@ size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx,
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</p></pre><BR>
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<a name="Chapter22"></a><h2>Block level API</h2><pre></pre>
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<a name="Chapter23"></a><h2>Block level API</h2><pre></pre>
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<pre><b></b><p> Frame metadata cost is typically ~18 bytes, which can be non-negligible for very small blocks (< 100 bytes).
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User will have to take in charge required information to regenerate data, such as compressed and content sizes.
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@ -187,7 +187,7 @@ unsigned ZSTD_isFrame(const void* buffer, size_t size)
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if (size < ZSTD_FRAMEIDSIZE) return 0;
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{ U32 const magic = MEM_readLE32(buffer);
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if (magic == ZSTD_MAGICNUMBER) return 1;
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if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) return 1;
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if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1;
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}
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#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
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if (ZSTD_isLegacy(buffer, size)) return 1;
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@ -242,7 +242,7 @@ size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, s
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if ( (format != ZSTD_f_zstd1_magicless)
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&& (MEM_readLE32(src) != ZSTD_MAGICNUMBER) ) {
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if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
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if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
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/* skippable frame */
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if (srcSize < ZSTD_SKIPPABLEHEADERSIZE)
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return ZSTD_SKIPPABLEHEADERSIZE; /* magic number + frame length */
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@ -355,7 +355,7 @@ unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize)
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while (srcSize >= ZSTD_FRAMEHEADERSIZE_PREFIX) {
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U32 const magicNumber = MEM_readLE32(src);
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if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
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if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
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size_t skippableSize;
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if (srcSize < ZSTD_SKIPPABLEHEADERSIZE)
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return ERROR(srcSize_wrong);
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@ -435,7 +435,7 @@ size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize)
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return ZSTD_findFrameCompressedSizeLegacy(src, srcSize);
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#endif
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if ( (srcSize >= ZSTD_SKIPPABLEHEADERSIZE)
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&& (MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START ) {
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&& (MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START ) {
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return ZSTD_SKIPPABLEHEADERSIZE + MEM_readLE32((const BYTE*)src + ZSTD_FRAMEIDSIZE);
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} else {
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const BYTE* ip = (const BYTE*)src;
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@ -659,7 +659,7 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
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{ U32 const magicNumber = MEM_readLE32(src);
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DEBUGLOG(4, "reading magic number %08X (expecting %08X)",
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(U32)magicNumber, (U32)ZSTD_MAGICNUMBER);
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if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
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if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
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size_t skippableSize;
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if (srcSize < ZSTD_SKIPPABLEHEADERSIZE)
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return ERROR(srcSize_wrong);
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@ -790,7 +790,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
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assert(src != NULL);
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if (dctx->format == ZSTD_f_zstd1) { /* allows header */
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assert(srcSize >= ZSTD_FRAMEIDSIZE); /* to read skippable magic number */
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if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
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if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
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memcpy(dctx->headerBuffer, src, srcSize);
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dctx->expected = ZSTD_SKIPPABLEHEADERSIZE - srcSize; /* remaining to load to get full skippable frame header */
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dctx->stage = ZSTDds_decodeSkippableHeader;
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@ -1419,7 +1419,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
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DEBUGLOG(4, "Consume header");
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CHECK_F(ZSTD_decompressBegin_usingDDict(zds, zds->ddict));
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if ((MEM_readLE32(zds->headerBuffer) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
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if ((MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
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zds->expected = MEM_readLE32(zds->headerBuffer + ZSTD_FRAMEIDSIZE);
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zds->stage = ZSTDds_skipFrame;
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} else {
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65
lib/zstd.h
65
lib/zstd.h
@ -415,9 +415,12 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void); /*!< recommended size for output
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ZSTDLIB_API int ZSTD_minCLevel(void); /*!< minimum negative compression level allowed */
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/* --- Constants ---*/
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#define ZSTD_MAGICNUMBER 0xFD2FB528 /* v0.8+ */
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#define ZSTD_MAGIC_DICTIONARY 0xEC30A437 /* v0.7+ */
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#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
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/* all magic numbers are supposed read/written to/from files/memory using little-endian convention */
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#define ZSTD_MAGICNUMBER 0xFD2FB528 /* valid since v0.8.0 */
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#define ZSTD_MAGIC_DICTIONARY 0xEC30A437 /* valid since v0.7.0 */
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#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50 /* all 16 values, from 0x184D2A50 to 0x184D2A5F, are understood as skippable frames */
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#define ZSTD_MAGIC_SKIPPABLE_MASK 0xFFFFFFF0
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#define ZSTD_BLOCKSIZELOG_MAX 17
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#define ZSTD_BLOCKSIZE_MAX (1<<ZSTD_BLOCKSIZELOG_MAX) /* define, for static allocation */
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@ -439,6 +442,20 @@ ZSTDLIB_API int ZSTD_minCLevel(void); /*!< minimum negative compression level a
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#define ZSTD_SEARCHLENGTH_MIN 3 /* only for ZSTD_btopt, other strategies are limited to 4 */
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#define ZSTD_TARGETLENGTH_MAX ZSTD_BLOCKSIZE_MAX
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#define ZSTD_TARGETLENGTH_MIN 0 /* note : comparing this constant to an unsigned results in a tautological test */
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/****************************************************************************************
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* Purely experimental API
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****************************************************************************************
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* The following symbols and constants are not planned
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* to join "stable API" status anytime soon.
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* Some of them might even be removed in the future.
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* ***************************************************************************************/
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#define ZSTD_LDM_MINMATCH_MAX 4096
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#define ZSTD_LDM_MINMATCH_MIN 4
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#define ZSTD_LDM_BUCKETSIZELOG_MAX 8
|
||||
@ -450,23 +467,33 @@ ZSTDLIB_API int ZSTD_minCLevel(void); /*!< minimum negative compression level a
|
||||
|
||||
|
||||
/* --- Advanced types --- */
|
||||
typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
|
||||
ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy; /* from faster to stronger */
|
||||
|
||||
/* Compression strategies, listed from fastest to strongest */
|
||||
typedef enum { ZSTD_fast=1,
|
||||
ZSTD_dfast=2,
|
||||
ZSTD_greedy=3,
|
||||
ZSTD_lazy=4,
|
||||
ZSTD_lazy2=5,
|
||||
ZSTD_btlazy2=6,
|
||||
ZSTD_btopt=7,
|
||||
ZSTD_btultra=8
|
||||
/* note : new strategies might be added in the future */
|
||||
} ZSTD_strategy;
|
||||
|
||||
typedef struct {
|
||||
unsigned windowLog; /**< largest match distance : larger == more compression, more memory needed during decompression */
|
||||
unsigned chainLog; /**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */
|
||||
unsigned hashLog; /**< dispatch table : larger == faster, more memory */
|
||||
unsigned searchLog; /**< nb of searches : larger == more compression, slower */
|
||||
unsigned searchLength; /**< match length searched : larger == faster decompression, sometimes less compression */
|
||||
unsigned targetLength; /**< acceptable match size for optimal parser (only) : larger == more compression, slower */
|
||||
ZSTD_strategy strategy;
|
||||
unsigned windowLog; /**< largest match distance : larger == more compression, more memory needed during decompression */
|
||||
unsigned chainLog; /**< fully searched segment : larger == more compression, slower, more memory (useless for fast) */
|
||||
unsigned hashLog; /**< dispatch table : larger == faster, more memory */
|
||||
unsigned searchLog; /**< nb of searches : larger == more compression, slower */
|
||||
unsigned searchLength; /**< match length searched : larger == faster decompression, sometimes less compression */
|
||||
unsigned targetLength; /**< acceptable match size for optimal parser (only) : larger == more compression, slower */
|
||||
ZSTD_strategy strategy; /**< see ZSTD_strategy definition above */
|
||||
} ZSTD_compressionParameters;
|
||||
|
||||
typedef struct {
|
||||
unsigned contentSizeFlag; /**< 1: content size will be in frame header (when known) */
|
||||
unsigned checksumFlag; /**< 1: generate a 32-bits checksum at end of frame, for error detection */
|
||||
unsigned noDictIDFlag; /**< 1: no dictID will be saved into frame header (if dictionary compression) */
|
||||
unsigned checksumFlag; /**< 1: generate a 32-bits checksum using XXH64 algorithm at end of frame, for error detection */
|
||||
unsigned noDictIDFlag; /**< 1: no dictID will be saved into frame header (dictID is only useful for dictionary compression) */
|
||||
} ZSTD_frameParameters;
|
||||
|
||||
typedef struct {
|
||||
@ -477,14 +504,14 @@ typedef struct {
|
||||
typedef struct ZSTD_CCtx_params_s ZSTD_CCtx_params;
|
||||
|
||||
typedef enum {
|
||||
ZSTD_dct_auto = 0, /* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */
|
||||
ZSTD_dct_rawContent, /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */
|
||||
ZSTD_dct_fullDict /* refuses to load a dictionary if it does not respect Zstandard's specification */
|
||||
ZSTD_dct_auto = 0, /* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */
|
||||
ZSTD_dct_rawContent = 1, /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */
|
||||
ZSTD_dct_fullDict = 2 /* refuses to load a dictionary if it does not respect Zstandard's specification, starting with ZSTD_MAGIC_DICTIONARY */
|
||||
} ZSTD_dictContentType_e;
|
||||
|
||||
typedef enum {
|
||||
ZSTD_dlm_byCopy = 0, /**< Copy dictionary content internally */
|
||||
ZSTD_dlm_byRef, /**< Reference dictionary content -- the dictionary buffer must outlive its users. */
|
||||
ZSTD_dlm_byCopy = 0, /**< Copy dictionary content internally */
|
||||
ZSTD_dlm_byRef = 1, /**< Reference dictionary content -- the dictionary buffer must outlive its users. */
|
||||
} ZSTD_dictLoadMethod_e;
|
||||
|
||||
|
||||
|
@ -2164,7 +2164,7 @@ FIO_analyzeFrames(fileInfo_t* info, FILE* const srcFile)
|
||||
info->numActualFrames++;
|
||||
}
|
||||
/* Skippable frame */
|
||||
else if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
|
||||
else if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
|
||||
U32 const frameSize = MEM_readLE32(headerBuffer + 4);
|
||||
long const seek = (long)(8 + frameSize - numBytesRead);
|
||||
ERROR_IF(LONG_SEEK(srcFile, seek, SEEK_CUR) != 0,
|
||||
|
Loading…
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Reference in New Issue
Block a user