diff --git a/lib/zstd.h b/lib/zstd.h index 1dff31b4e70..63f1f553c15 100644 --- a/lib/zstd.h +++ b/lib/zstd.h @@ -990,8 +990,9 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize); * @result : 0, or an error code (which can be tested with ZSTD_isError()). * Special: Loading a NULL (or 0-size) dictionary invalidates previous dictionary, * meaning "return to no-dictionary mode". - * Note 1 : Dictionary is sticky, it will be used for all future compressed frames. - * To return to "no-dictionary" situation, load a NULL dictionary (or reset parameters). + * Note 1 : Dictionary is sticky, it will be used for all future compressed frames, + * until parameters are reset, a new dictionary is loaded, or the dictionary + * is explicitly invalidated by loading a NULL dictionary. * Note 2 : Loading a dictionary involves building tables. * It's also a CPU consuming operation, with non-negligible impact on latency. * Tables are dependent on compression parameters, and for this reason, @@ -1004,7 +1005,7 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize); ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize); /*! ZSTD_CCtx_refCDict() : Requires v1.4.0+ - * Reference a prepared dictionary, to be used for all next compressed frames. + * Reference a prepared dictionary, to be used for all future compressed frames. * Note that compression parameters are enforced from within CDict, * and supersede any compression parameter previously set within CCtx. * The parameters ignored are labelled as "superseded-by-cdict" in the ZSTD_cParameter enum docs. @@ -1039,9 +1040,9 @@ ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize); /*! ZSTD_DCtx_loadDictionary() : Requires v1.4.0+ - * Create an internal DDict from dict buffer, - * to be used to decompress next frames. - * The dictionary remains valid for all future frames, until explicitly invalidated. + * Create an internal DDict from dict buffer, to be used to decompress all future frames. + * The dictionary remains valid for all future frames, until explicitly invalidated, or + * a new dictionary is loaded. * @result : 0, or an error code (which can be tested with ZSTD_isError()). * Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary, * meaning "return to no-dictionary mode". @@ -1065,9 +1066,10 @@ ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, s * The memory for the table is allocated on the first call to refDDict, and can be * freed with ZSTD_freeDCtx(). * + * If called with ZSTD_d_refMultipleDDicts disabled (the default), only one dictionary + * will be managed, and referencing a dictionary effectively "discards" any previous one. + * * @result : 0, or an error code (which can be tested with ZSTD_isError()). - * Note 1 : Currently, only one dictionary can be managed. - * Referencing a new dictionary effectively "discards" any previous one. * Special: referencing a NULL DDict means "return to no-dictionary mode". * Note 2 : DDict is just referenced, its lifetime must outlive its usage from DCtx. */