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-<title>zstd 1.5.6 Manual</title>
+<title>zstd 1.5.7 Manual</title>
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-<h1>zstd 1.5.6 Manual</h1>
+<h1>zstd 1.5.7 Manual</h1>
+Note: the content of this file has been automatically generated by parsing "zstd.h"
<hr>
<a name="Contents"></a><h2>Contents</h2>
<ol>
</p></pre><BR>
<h3>Compression helper functions</h3><pre></pre><b><pre></pre></b><BR>
-<pre><b>size_t ZSTD_compressBound(size_t srcSize); </b>/*!< maximum compressed size in worst case single-pass scenario */<b>
-</b></pre><BR>
+<pre><b>#define ZSTD_MAX_INPUT_SIZE ((sizeof(size_t)==8) ? 0xFF00FF00FF00FF00ULL : 0xFF00FF00U)
+#define ZSTD_COMPRESSBOUND(srcSize) (((size_t)(srcSize) >= ZSTD_MAX_INPUT_SIZE) ? 0 : (srcSize) + ((srcSize)>>8) + (((srcSize) < (128<<10)) ? (((128<<10) - (srcSize)) >> 11) </b>/* margin, from 64 to 0 */ : 0)) /* this formula ensures that bound(A) + bound(B) <= bound(A+B) as long as A and B >= 128 KB */<b>
+size_t ZSTD_compressBound(size_t srcSize); </b>/*!< maximum compressed size in worst case single-pass scenario */<b>
+</b><p> maximum compressed size in worst case single-pass scenario.
+ When invoking `ZSTD_compress()`, or any other one-pass compression function,
+ it's recommended to provide @dstCapacity >= ZSTD_compressBound(srcSize)
+ as it eliminates one potential failure scenario,
+ aka not enough room in dst buffer to write the compressed frame.
+ Note : ZSTD_compressBound() itself can fail, if @srcSize > ZSTD_MAX_INPUT_SIZE .
+ In which case, ZSTD_compressBound() will return an error code
+ which can be tested using ZSTD_isError().
+
+ ZSTD_COMPRESSBOUND() :
+ same as ZSTD_compressBound(), but as a macro.
+ It can be used to produce constants, which can be useful for static allocation,
+ for example to size a static array on stack.
+ Will produce constant value 0 if srcSize is too large.
+
+</p></pre><BR>
+
<h3>Error helper functions</h3><pre></pre><b><pre>#include "zstd_errors.h" </b>/* list of errors */<b>
</b>/* ZSTD_isError() :<b>
* Most ZSTD_* functions returning a size_t value can be tested for error,
* using ZSTD_isError().
* @return 1 if error, 0 otherwise
*/
-unsigned ZSTD_isError(size_t code); </b>/*!< tells if a `size_t` function result is an error code */<b>
+unsigned ZSTD_isError(size_t result); </b>/*!< tells if a `size_t` function result is an error code */<b>
ZSTD_ErrorCode ZSTD_getErrorCode(size_t functionResult); </b>/* convert a result into an error code, which can be compared to error enum list */<b>
-const char* ZSTD_getErrorName(size_t code); </b>/*!< provides readable string from an error code */<b>
+const char* ZSTD_getErrorName(size_t result); </b>/*!< provides readable string from a function result */<b>
int ZSTD_minCLevel(void); </b>/*!< minimum negative compression level allowed, requires v1.4.0+ */<b>
int ZSTD_maxCLevel(void); </b>/*!< maximum compression level available */<b>
int ZSTD_defaultCLevel(void); </b>/*!< default compression level, specified by ZSTD_CLEVEL_DEFAULT, requires v1.5.0+ */<b>
<a name="Chapter4"></a><h2>Explicit context</h2><pre></pre>
<h3>Compression context</h3><pre> When compressing many times,
- it is recommended to allocate a context just once,
+ it is recommended to allocate a compression context just once,
and reuse it for each successive compression operation.
- This will make workload friendlier for system's memory.
+ This will make the workload easier for system's memory.
Note : re-using context is just a speed / resource optimization.
It doesn't change the compression ratio, which remains identical.
- Note 2 : In multi-threaded environments,
- use one different context per thread for parallel execution.
+ Note 2: For parallel execution in multi-threaded environments,
+ use one different context per thread .
</pre><b><pre>typedef struct ZSTD_CCtx_s ZSTD_CCtx;
ZSTD_CCtx* ZSTD_createCCtx(void);
-size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); </b>/* accept NULL pointer */<b>
+size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx); </b>/* compatible with NULL pointer */<b>
</pre></b><BR>
<pre><b>size_t ZSTD_compressCCtx(ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
this function compresses at the requested compression level,
__ignoring any other advanced parameter__ .
If any advanced parameter was set using the advanced API,
- they will all be reset. Only `compressionLevel` remains.
+ they will all be reset. Only @compressionLevel remains.
</p></pre><BR>
* ZSTD_c_stableOutBuffer
* ZSTD_c_blockDelimiters
* ZSTD_c_validateSequences
- * ZSTD_c_useBlockSplitter
+ * ZSTD_c_blockSplitterLevel
+ * ZSTD_c_splitAfterSequences
* ZSTD_c_useRowMatchFinder
* ZSTD_c_prefetchCDictTables
* ZSTD_c_enableSeqProducerFallback
ZSTD_c_experimentalParam16=1013,
ZSTD_c_experimentalParam17=1014,
ZSTD_c_experimentalParam18=1015,
- ZSTD_c_experimentalParam19=1016
+ ZSTD_c_experimentalParam19=1016,
+ ZSTD_c_experimentalParam20=1017
} ZSTD_cParameter;
</b></pre><BR>
<pre><b>typedef struct {
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