[3.14] gh-132983: Clean-ups for `_zstd` (GH-133670) (#133756)

gh-132983: Clean-ups for ``_zstd`` (GH-133670)
(cherry picked from commit c2a5d4b383)

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>

Lib/compression/zstd/__init__.py

@@ -28,10 +28,16 @@ __all__ = (
 
 import _zstd
 import enum
-from _zstd import *
+from _zstd import (ZstdCompressor, ZstdDecompressor, ZstdDict, ZstdError,
+                   get_frame_size, zstd_version)
 from compression.zstd._zstdfile import ZstdFile, open, _nbytes
 
-COMPRESSION_LEVEL_DEFAULT = _zstd._compressionLevel_values[0]
+# zstd_version_number is (MAJOR * 100 * 100 + MINOR * 100 + RELEASE)
+zstd_version_info = (*divmod(_zstd.zstd_version_number // 100, 100),
+                     _zstd.zstd_version_number % 100)
+"""Version number of the runtime zstd library as a tuple of integers."""
+
+COMPRESSION_LEVEL_DEFAULT = _zstd.ZSTD_CLEVEL_DEFAULT
 """The default compression level for Zstandard, currently '3'."""
 
 
@@ -167,28 +173,28 @@ def decompress(data, zstd_dict=None, options=None):
 class CompressionParameter(enum.IntEnum):
     """Compression parameters."""
 
-    compression_level = _zstd._ZSTD_c_compressionLevel
-    window_log = _zstd._ZSTD_c_windowLog
-    hash_log = _zstd._ZSTD_c_hashLog
-    chain_log = _zstd._ZSTD_c_chainLog
-    search_log = _zstd._ZSTD_c_searchLog
-    min_match = _zstd._ZSTD_c_minMatch
-    target_length = _zstd._ZSTD_c_targetLength
-    strategy = _zstd._ZSTD_c_strategy
+    compression_level = _zstd.ZSTD_c_compressionLevel
+    window_log = _zstd.ZSTD_c_windowLog
+    hash_log = _zstd.ZSTD_c_hashLog
+    chain_log = _zstd.ZSTD_c_chainLog
+    search_log = _zstd.ZSTD_c_searchLog
+    min_match = _zstd.ZSTD_c_minMatch
+    target_length = _zstd.ZSTD_c_targetLength
+    strategy = _zstd.ZSTD_c_strategy
 
-    enable_long_distance_matching = _zstd._ZSTD_c_enableLongDistanceMatching
-    ldm_hash_log = _zstd._ZSTD_c_ldmHashLog
-    ldm_min_match = _zstd._ZSTD_c_ldmMinMatch
-    ldm_bucket_size_log = _zstd._ZSTD_c_ldmBucketSizeLog
-    ldm_hash_rate_log = _zstd._ZSTD_c_ldmHashRateLog
+    enable_long_distance_matching = _zstd.ZSTD_c_enableLongDistanceMatching
+    ldm_hash_log = _zstd.ZSTD_c_ldmHashLog
+    ldm_min_match = _zstd.ZSTD_c_ldmMinMatch
+    ldm_bucket_size_log = _zstd.ZSTD_c_ldmBucketSizeLog
+    ldm_hash_rate_log = _zstd.ZSTD_c_ldmHashRateLog
 
-    content_size_flag = _zstd._ZSTD_c_contentSizeFlag
-    checksum_flag = _zstd._ZSTD_c_checksumFlag
-    dict_id_flag = _zstd._ZSTD_c_dictIDFlag
+    content_size_flag = _zstd.ZSTD_c_contentSizeFlag
+    checksum_flag = _zstd.ZSTD_c_checksumFlag
+    dict_id_flag = _zstd.ZSTD_c_dictIDFlag
 
-    nb_workers = _zstd._ZSTD_c_nbWorkers
-    job_size = _zstd._ZSTD_c_jobSize
-    overlap_log = _zstd._ZSTD_c_overlapLog
+    nb_workers = _zstd.ZSTD_c_nbWorkers
+    job_size = _zstd.ZSTD_c_jobSize
+    overlap_log = _zstd.ZSTD_c_overlapLog
 
     def bounds(self):
         """Return the (lower, upper) int bounds of a compression parameter.
@@ -201,7 +207,7 @@ class CompressionParameter(enum.IntEnum):
 class DecompressionParameter(enum.IntEnum):
     """Decompression parameters."""
 
-    window_log_max = _zstd._ZSTD_d_windowLogMax
+    window_log_max = _zstd.ZSTD_d_windowLogMax
 
     def bounds(self):
         """Return the (lower, upper) int bounds of a decompression parameter.
@@ -219,15 +225,15 @@ class Strategy(enum.IntEnum):
     the numeric value might change.
     """
 
-    fast = _zstd._ZSTD_fast
-    dfast = _zstd._ZSTD_dfast
-    greedy = _zstd._ZSTD_greedy
-    lazy = _zstd._ZSTD_lazy
-    lazy2 = _zstd._ZSTD_lazy2
-    btlazy2 = _zstd._ZSTD_btlazy2
-    btopt = _zstd._ZSTD_btopt
-    btultra = _zstd._ZSTD_btultra
-    btultra2 = _zstd._ZSTD_btultra2
+    fast = _zstd.ZSTD_fast
+    dfast = _zstd.ZSTD_dfast
+    greedy = _zstd.ZSTD_greedy
+    lazy = _zstd.ZSTD_lazy
+    lazy2 = _zstd.ZSTD_lazy2
+    btlazy2 = _zstd.ZSTD_btlazy2
+    btopt = _zstd.ZSTD_btopt
+    btultra = _zstd.ZSTD_btultra
+    btultra2 = _zstd.ZSTD_btultra2
 
 
 # Check validity of the CompressionParameter & DecompressionParameter types

Lib/compression/zstd/_zstdfile.py

@@ -1,13 +1,11 @@
 import io
 from os import PathLike
-from _zstd import (ZstdCompressor, ZstdDecompressor, _ZSTD_DStreamSizes,
-                   ZstdError)
+from _zstd import (ZstdCompressor, ZstdDecompressor, ZstdError,
+                   ZSTD_DStreamOutSize)
 from compression._common import _streams
 
 __all__ = ("ZstdFile", "open")
 
-_ZSTD_DStreamOutSize = _ZSTD_DStreamSizes[1]
-
 _MODE_CLOSED = 0
 _MODE_READ = 1
 _MODE_WRITE = 2
@@ -188,7 +186,7 @@ class ZstdFile(_streams.BaseStream):
             # Note this should *not* be io.DEFAULT_BUFFER_SIZE.
             # ZSTD_DStreamOutSize is the minimum amount to read guaranteeing
             # a full block is read.
-            size = _ZSTD_DStreamOutSize
+            size = ZSTD_DStreamOutSize
         return self._buffer.read1(size)
 
     def readinto(self, b):