docs: capture missing features in own document

Pulled a lot of content from `news.rst` into a new page. Also
added some items from 1.5.4.

Author: indygreg

Cargo.lock

@@ -18,3 +18,4 @@ python-zstandard
    buffer
    contributing
    news
+   missing_features

docs/index.rst

@@ -0,0 +1,74 @@
+==================================
+Missing and Unimplemented Features
+==================================
+
+This document attempts to capture features of the zstd C API that are currently
+not exposed to Python.
+
+If there is a feature on this page that would be beneficial to you, please
+open a GitHub issue requesting its implementation. If an existing GitHub
+issue exists, please leave a comment on the issue to amplify the importance of
+the request (this project's author doesn't monitor the emoji counts).
+
+Missing Constants
+=================
+
+* ``ZSTD_CLEVEL_DEFAULT``
+* ``ZSTD_SRCSIZEHINT_MIN``
+* ``ZSTD_SRCSIZEHINT_MAX``
+* ``ZSTD_BLOCKSIZE_MAX_MIN``
+* ``ZSTD_DECOMPRESSION_MARGIN``
+
+Compression and Decompression Parameters
+========================================
+
+* ``ZSTD_p_forceAttachDict``
+* ``ZSTD_dictForceLoad``
+* ``ZSTD_c_targetCBlockSize``
+* ``ZSTD_c_literalCompressionMode``
+* ``ZSTD_c_srcSizeHint``
+* ``ZSTD_d_stableOutBuffer``
+* ``ZSTD_c_enableDedicatedDictSearch``
+* ``ZSTD_c_stableInBuffer``
+* ``ZSTD_c_stableOutBuffer``
+* ``ZSTD_c_blockDelimiters``
+* ``ZSTD_c_validateSequences``
+* ``ZSTD_c_useBlockSplitter``
+* ``ZSTD_c_useRowMatchFinder``
+* ``ZSTD_d_forceIgnoreChecksum``
+* ``ZSTD_d_refMultipleDDicts``
+* ``ZSTD_refMultipleDDicts_e``
+* ``ZSTD_c_prefetchCDictTables``
+* ``ZSTD_c_enableSeqProducerFallback``
+* ``ZSTD_c_maxBlockSize``
+* ``ZSTD_c_searchForExternalRepcodes``
+* ``ZSTD_d_disableHuffmanAssembly``
+* ``ZSTD_d_stableOutBuffer``
+
+Missing Functions
+=================
+
+* ``ZSTDMT_toFlushNow()``
+* ``ZSTD_minCLevel()``
+* ``ZSTD_cParam_getBounds()``
+* ``ZSTD_dParam_getBounds()``
+* ``ZSTD_generateSequences()``
+* ``ZSTD_mergeBlockDelimiters()``
+* ``ZSTD_compressSequences()``
+* ``ZSTD_writeSkippableFrame()``
+* ``ZSTD_decompressionMargin()``
+* ``ZSTD_sequenceBound()``
+
+Missing Features
+================
+
+* ``ZSTD_getFrameProgression()`` isn't exposed everywhere it could be.
+* Compression parameters cannot be modified mid operation.
+* ``ZSTD_Sequence`` and related ``ZSTD_getSequences()`` not exposed.
+* ``ZSTD_threadPool`` not exposed.
+* ``ZSTD_sequenceProducer_F`` and ``ZSTD_registerSequenceProducer()`` not
+  exposed.
+* ``ZSTD_CCtx_getParameter()``, ``ZSTD_CCtxParam_getParameter()``, and
+  ``ZSTD_DCtx_getParameter()`` could be leveraged for parameter retrieval.
+* ``ZSTD_CCtx_setCParams()`` could potentially be utilized.
+* ``ZSTD_error_*`` constants / error codes not exposed.

docs/missing_features.rst

@@ -30,46 +30,12 @@ Actions Blocking Release
 * Detect memory leaks via bench.py.
 * Remove low-level compression parameters from ``ZstdCompressor.__init__`` and
   require use of ``ZstdCompressionParameters``.
-* Expose ``ZSTD_getFrameProgression()`` from more compressor types.
-* Support modifying compression parameters mid operation when supported by
-  zstd API.
-* Expose ``ZSTD_CLEVEL_DEFAULT`` constant.
-* Expose ``ZSTD_SRCSIZEHINT_{MIN,MAX}`` constants.
-* Support ``ZSTD_p_forceAttachDict`` compression parameter.
-* Support ``ZSTD_dictForceLoad`` dictionary compression parameter.
-* Support ``ZSTD_c_targetCBlockSize`` compression parameter.
-* Support ``ZSTD_c_literalCompressionMode`` compression parameter.
-* Support ``ZSTD_c_srcSizeHint`` compression parameter.
-* Use ``ZSTD_CCtx_getParameter()``/``ZSTD_CCtxParam_getParameter()`` for retrieving
-  compression parameters.
-* Consider exposing ``ZSTDMT_toFlushNow()``.
-* Expose ``ZSTD_Sequence`` struct and related ``ZSTD_getSequences()`` API.
-* Expose and enforce ``ZSTD_minCLevel()`` for minimum compression level.
 * Consider a ``chunker()`` API for decompression.
 * Consider stats for ``chunker()`` API, including finding the last consumed
   offset of input data.
-* Consider exposing ``ZSTD_cParam_getBounds()`` and
-  ``ZSTD_dParam_getBounds()`` APIs.
 * Consider controls over resetting compression contexts (session only, parameters,
   or session and parameters).
-* Consider exposing ``ZSTD_d_stableOutBuffer``.
-* Support ``ZSTD_c_enableDedicatedDictSearch``.
-* Support ``ZSTD_c_stableInBuffer``.
-* Support ``ZSTD_c_stableOutBuffer``.
-* Support ``ZSTD_c_blockDelimiters``.
-* Support ``ZSTD_c_validateSequences``.
-* Support ``ZSTD_c_useBlockSplitter``.
-* Support ``ZSTD_c_useRowMatchFinder``.
-* Support ``ZSTD_d_forceIgnoreChecksum``.
-* Support ``ZSTD_d_refMultipleDDicts``.
-* Support ``ZSTD_generateSequences()``.
-* Support ``ZSTD_mergeBlockDelimiters()``.
-* Support ``ZSTD_compressSequences()``.
-* Support ``ZSTD_threadPool`` APIs for managing a thread pool.
-* Support ``ZSTD_refMultipleDDicts_e``.
-* Support ``ZSTD_writeSkippableFrame()``.
 * Utilize ``ZSTD_getDictID_fromCDict()``?
-* Utilize ``ZSTD_DCtx_getParameter()``.
 * Stop relying on private libzstd headers and symbols (namely ``pool.h``).
 
 Other Actions Not Blocking Release