Issue #14366: Support lzma compression in zip files.
Patch by Serhiy Storchaka.
diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index c53b127..c127c2c 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -27,8 +27,13 @@
except ImportError:
bz2 = None
+try:
+ import lzma # We may need its compression method
+except ImportError:
+ lzma = None
+
__all__ = ["BadZipFile", "BadZipfile", "error",
- "ZIP_STORED", "ZIP_DEFLATED", "ZIP_BZIP2",
+ "ZIP_STORED", "ZIP_DEFLATED", "ZIP_BZIP2", "ZIP_LZMA",
"is_zipfile", "ZipInfo", "ZipFile", "PyZipFile", "LargeZipFile"]
class BadZipFile(Exception):
@@ -52,13 +57,15 @@
ZIP_STORED = 0
ZIP_DEFLATED = 8
ZIP_BZIP2 = 12
+ZIP_LZMA = 14
# Other ZIP compression methods not supported
DEFAULT_VERSION = 20
ZIP64_VERSION = 45
BZIP2_VERSION = 46
+LZMA_VERSION = 63
# we recognize (but not necessarily support) all features up to that version
-MAX_EXTRACT_VERSION = 46
+MAX_EXTRACT_VERSION = 63
# Below are some formats and associated data for reading/writing headers using
# the struct module. The names and structures of headers/records are those used
@@ -367,6 +374,8 @@
if self.compress_type == ZIP_BZIP2:
min_version = max(BZIP2_VERSION, min_version)
+ elif self.compress_type == ZIP_LZMA:
+ min_version = max(LZMA_VERSION, min_version)
self.extract_version = max(min_version, self.extract_version)
self.create_version = max(min_version, self.create_version)
@@ -480,6 +489,77 @@
return c
+class LZMACompressor:
+
+ def __init__(self):
+ self._comp = None
+
+ def _init(self):
+ props = lzma.encode_filter_properties({'id': lzma.FILTER_LZMA1})
+ self._comp = lzma.LZMACompressor(lzma.FORMAT_RAW, filters=[
+ lzma.decode_filter_properties(lzma.FILTER_LZMA1, props)
+ ])
+ return struct.pack('<BBH', 9, 4, len(props)) + props
+
+ def compress(self, data):
+ if self._comp is None:
+ return self._init() + self._comp.compress(data)
+ return self._comp.compress(data)
+
+ def flush(self):
+ if self._comp is None:
+ return self._init() + self._comp.flush()
+ return self._comp.flush()
+
+
+class LZMADecompressor:
+
+ def __init__(self):
+ self._decomp = None
+ self._unconsumed = b''
+ self.eof = False
+
+ def decompress(self, data):
+ if self._decomp is None:
+ self._unconsumed += data
+ if len(self._unconsumed) <= 4:
+ return b''
+ psize, = struct.unpack('<H', self._unconsumed[2:4])
+ if len(self._unconsumed) <= 4 + psize:
+ return b''
+
+ self._decomp = lzma.LZMADecompressor(lzma.FORMAT_RAW, filters=[
+ lzma.decode_filter_properties(lzma.FILTER_LZMA1,
+ self._unconsumed[4:4 + psize])
+ ])
+ data = self._unconsumed[4 + psize:]
+ del self._unconsumed
+
+ result = self._decomp.decompress(data)
+ self.eof = self._decomp.eof
+ return result
+
+
+compressor_names = {
+ 0: 'store',
+ 1: 'shrink',
+ 2: 'reduce',
+ 3: 'reduce',
+ 4: 'reduce',
+ 5: 'reduce',
+ 6: 'implode',
+ 7: 'tokenize',
+ 8: 'deflate',
+ 9: 'deflate64',
+ 10: 'implode',
+ 12: 'bzip2',
+ 14: 'lzma',
+ 18: 'terse',
+ 19: 'lz77',
+ 97: 'wavpack',
+ 98: 'ppmd',
+}
+
def _check_compression(compression):
if compression == ZIP_STORED:
pass
@@ -491,6 +571,10 @@
if not bz2:
raise RuntimeError(
"Compression requires the (missing) bz2 module")
+ elif compression == ZIP_LZMA:
+ if not lzma:
+ raise RuntimeError(
+ "Compression requires the (missing) lzma module")
else:
raise RuntimeError("That compression method is not supported")
@@ -501,6 +585,8 @@
zlib.DEFLATED, -15)
elif compress_type == ZIP_BZIP2:
return bz2.BZ2Compressor()
+ elif compress_type == ZIP_LZMA:
+ return LZMACompressor()
else:
return None
@@ -512,19 +598,10 @@
return zlib.decompressobj(-15)
elif compress_type == ZIP_BZIP2:
return bz2.BZ2Decompressor()
+ elif compress_type == ZIP_LZMA:
+ return LZMADecompressor()
else:
- unknown_compressors = {
- 1: 'shrink',
- 2: 'reduce',
- 3: 'reduce',
- 4: 'reduce',
- 5: 'reduce',
- 6: 'implode',
- 9: 'enhanced deflate',
- 10: 'implode',
- 14: 'lzma',
- }
- descr = unknown_compressors.get(compress_type)
+ descr = compressor_names.get(compress_type)
if descr:
raise NotImplementedError("compression type %d (%s)" % (compress_type, descr))
else:
@@ -781,8 +858,8 @@
file: Either the path to the file, or a file-like object.
If it is a path, the file will be opened and closed by ZipFile.
mode: The mode can be either read "r", write "w" or append "a".
- compression: ZIP_STORED (no compression), ZIP_DEFLATED (requires zlib) or
- ZIP_BZIP2 (requires bz2).
+ compression: ZIP_STORED (no compression), ZIP_DEFLATED (requires zlib),
+ ZIP_BZIP2 (requires bz2) or ZIP_LZMA (requires lzma).
allowZip64: if True ZipFile will create files with ZIP64 extensions when
needed, otherwise it will raise an exception when this would
be necessary.
@@ -1062,6 +1139,10 @@
# Zip 2.7: compressed patched data
raise NotImplementedError("compressed patched data (flag bit 5)")
+ if zinfo.flag_bits & 0x40:
+ # strong encryption
+ raise NotImplementedError("strong encryption (flag bit 6)")
+
if zinfo.flag_bits & 0x800:
# UTF-8 filename
fname_str = fname.decode("utf-8")
@@ -1220,6 +1301,9 @@
zinfo.file_size = st.st_size
zinfo.flag_bits = 0x00
zinfo.header_offset = self.fp.tell() # Start of header bytes
+ if zinfo.compress_type == ZIP_LZMA:
+ # Compressed data includes an end-of-stream (EOS) marker
+ zinfo.flag_bits |= 0x02
self._writecheck(zinfo)
self._didModify = True
@@ -1292,6 +1376,9 @@
zinfo.header_offset = self.fp.tell() # Start of header data
if compress_type is not None:
zinfo.compress_type = compress_type
+ if zinfo.compress_type == ZIP_LZMA:
+ # Compressed data includes an end-of-stream (EOS) marker
+ zinfo.flag_bits |= 0x02
self._writecheck(zinfo)
self._didModify = True
@@ -1360,6 +1447,8 @@
if zinfo.compress_type == ZIP_BZIP2:
min_version = max(BZIP2_VERSION, min_version)
+ elif zinfo.compress_type == ZIP_LZMA:
+ min_version = max(LZMA_VERSION, min_version)
extract_version = max(min_version, zinfo.extract_version)
create_version = max(min_version, zinfo.create_version)