From 3bfd3be5fb0d11813a57c10bf947224b998e696c Mon Sep 17 00:00:00 2001 From: Elliot Gorokhovsky Date: Mon, 23 Jan 2023 13:28:36 -0500 Subject: [PATCH] Fix ZSTD_estimate* and ZSTD_initCStream() docs Fix the following documentation bugs: * Note that `ZSTD_estimate*` functions are not compatible with the external matchfinder API * Note that `ZSTD_estimateCStreamSize_usingCCtxParams()` is not compatible with `nbWorkers >= 1` * Remove incorrect warning that the legacy streaming API is incompatible with advanced parameters and/or dictionary compression * Note that `ZSTD_initCStream()` is incompatible with dictionary compression * Warn that --- lib/zstd.h | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/lib/zstd.h b/lib/zstd.h index a2e023452..d2c5d3ff5 100644 --- a/lib/zstd.h +++ b/lib/zstd.h @@ -799,8 +799,6 @@ ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output * This following is a legacy streaming API, available since v1.0+ . * It can be replaced by ZSTD_CCtx_reset() and ZSTD_compressStream2(). * It is redundant, but remains fully supported. - * Streaming in combination with advanced parameters and dictionary compression - * can only be used through the new API. ******************************************************************************/ /*! @@ -809,6 +807,9 @@ ZSTDLIB_API size_t ZSTD_CStreamOutSize(void); /**< recommended size for output * ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only); * ZSTD_CCtx_refCDict(zcs, NULL); // clear the dictionary (if any) * ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel); + * + * Note that ZSTD_initCStream() clears any previously set dictionary. Use the new API + * to compress with a dictionary. */ ZSTDLIB_API size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel); /*! @@ -1620,8 +1621,11 @@ ZSTDLIB_API unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size); * and ZSTD_estimateCCtxSize_usingCCtxParams(), which can be used in tandem with ZSTD_CCtxParams_setParameter(). * Both can be used to estimate memory using custom compression parameters and arbitrary srcSize limits. * - * Note 2 : only single-threaded compression is supported. + * Note : only single-threaded compression is supported. * ZSTD_estimateCCtxSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. + * + * Note 2 : ZSTD_estimateCCtxSize* functions are not compatible with the external matchfinder API at this time. + * Size estimates assume that no external matchfinder is registered. */ ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize(int compressionLevel); ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams); @@ -1640,7 +1644,12 @@ ZSTDLIB_STATIC_API size_t ZSTD_estimateDCtxSize(void); * or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame(); * Note : if streaming is init with function ZSTD_init?Stream_usingDict(), * an internal ?Dict will be created, which additional size is not estimated here. - * In this case, get total size by adding ZSTD_estimate?DictSize */ + * In this case, get total size by adding ZSTD_estimate?DictSize + * Note 2 : only single-threaded compression is supported. + * ZSTD_estimateCStreamSize_usingCCtxParams() will return an error code if ZSTD_c_nbWorkers is >= 1. + * Note 3 : ZSTD_estimateCStreamSize* functions are not compatible with the external matchfinder API at this time. + * Size estimates assume that no external matchfinder is registered. + */ ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize(int compressionLevel); ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams); ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params);