def __init__(self):
if Zstd is None:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
ctx = Zstd.ZstdCompressor() # type: ignore
self._compressor = ctx.stream_writer(self._buf)
self.flushed = False
def __init__(self, properties):
if Zstd is None or len(properties) not in [
3, 5
] or (properties[0], properties[1], 0) > Zstd.ZSTD_VERSION:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
ctx = Zstd.ZstdDecompressor() # type: ignore
self._decompressor = ctx.stream_writer(self._buf)
class PpmdCompressor(ISevenZipCompressor):
"""Compress with PPMd compression algorithm"""
def __init__(self, level: int, mem: int, blocksize: Optional[int] = None):
self._buf = BufferedRW(blocksize)
self.encoder = Ppmd.Ppmd7Encoder(self._buf, level, mem) # type: ignore
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
self.encoder.encode(data)
return self._buf.read()
def flush(self):
self.encoder.flush()
return self._buf.read()
class PpmdCompressor(ISevenZipCompressor):
def __init__(self, level: int, mem: int):
if Ppmd is None:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
self.encoder = Ppmd.Ppmd7Encoder(self._buf, level, mem) # type: ignore
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
self.encoder.encode(data)
return self._buf.read()
def flush(self):
self.encoder.flush()
return self._buf.read()
def __init__(self, properties: bytes):
if Ppmd is None:
raise UnsupportedCompressionMethodError
if not isinstance(properties, bytes):
raise UnsupportedCompressionMethodError
if len(properties) == 5:
level, mem = struct.unpack("<BL", properties)
elif len(properties) == 7:
level, mem, _, _ = struct.unpack("<BLBB", properties)
else:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
self.decoder = None
self.level = level
self.mem = mem
self.initialized = False
class ZstdDecompressor(ISevenZipDecompressor):
def __init__(self, properties):
if Zstd is None or len(properties) not in [3, 5] or (properties[0], properties[1], 0) > Zstd.ZSTD_VERSION:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
ctx = Zstd.ZstdDecompressor() # type: ignore
self._decompressor = ctx.stream_writer(self._buf)
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
self._decompressor.write(data)
if max_length > 0:
result = self._buf.read(max_length)
else:
result = self._buf.read()
return result
class PpmdDecompressor(ISevenZipDecompressor):
"""Decompress PPMd compressed data"""
def __init__(self, properties: bytes, blocksize: Optional[int] = None):
if not isinstance(properties, bytes):
raise UnsupportedCompressionMethodError
if len(properties) == 5:
level, mem = struct.unpack("<BL", properties)
elif len(properties) == 7:
level, mem, _, _ = struct.unpack("<BLBB", properties)
else:
raise UnsupportedCompressionMethodError
if blocksize:
self.block_size = blocksize
else:
self.block_size = get_default_blocksize()
self._buf = BufferedRW(self.block_size)
self._buf = BufferedRW()
self.decoder = None
self.level = level
self.mem = mem
self.initialized = False
def _init2(self):
self.decoder = Ppmd.Ppmd7Decoder(self._buf, self.level,
self.mem) # type: ignore
self.initialized = True
def decompress(self,
data: Union[bytes, bytearray, memoryview],
max_length=-1) -> bytes:
self._buf.write(data)
if not self.initialized:
if len(self._buf) <= 4:
return b""
self._init2()
assert self.decoder is not None
if max_length <= 0:
return self.decoder.decode(1)
if len(data) == 0:
return self.decoder.decode(max_length)
#
size = min(self.block_size, max_length)
res = bytearray()
while len(self._buf) > 0 and len(res) < size:
res += self.decoder.decode(1)
return bytes(res)
def __init__(self, properties: bytes, blocksize: Optional[int] = None):
if not isinstance(properties, bytes):
raise UnsupportedCompressionMethodError
if len(properties) == 5:
level, mem = struct.unpack("<BL", properties)
elif len(properties) == 7:
level, mem, _, _ = struct.unpack("<BLBB", properties)
else:
raise UnsupportedCompressionMethodError
if blocksize:
self.block_size = blocksize
else:
self.block_size = get_default_blocksize()
self._buf = BufferedRW(self.block_size)
self._buf = BufferedRW()
self.decoder = None
self.level = level
self.mem = mem
self.initialized = False
class ZstdCompressor():
def __init__(self, level):
self._buf = BufferedRW()
ctx = zstandard.ZstdCompressor(level) # type: ignore
self._compressor = ctx.stream_writer(self._buf)
self.flushed = False
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
self._compressor.write(data)
result = self._buf.read()
return result
def flush(self):
if self.flushed:
return None
self._compressor.flush(zstandard.FLUSH_FRAME)
self.flushed = True
result = self._buf.read()
return result
class ZstdCompressor(ISevenZipCompressor):
def __init__(self):
if Zstd is None:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
ctx = Zstd.ZstdCompressor() # type: ignore
self._compressor = ctx.stream_writer(self._buf)
self.flushed = False
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
self._compressor.write(data)
result = self._buf.read()
return result
def flush(self):
if self.flushed:
return None
self._compressor.flush(Zstd.FLUSH_FRAME)
self.flushed = True
result = self._buf.read()
return result
def __init__(self, level: int, mem: int):
if Ppmd is None:
raise UnsupportedCompressionMethodError
self._buf = BufferedRW()
self.encoder = Ppmd.Ppmd7Encoder(self._buf, level, mem) # type: ignore
def __init__(self, level: int, mem: int, blocksize: Optional[int] = None):
self._buf = BufferedRW(blocksize)
self.encoder = Ppmd.Ppmd7Encoder(self._buf, level, mem) # type: ignore
def __init__(self, level):
self._buf = BufferedRW()
ctx = zstandard.ZstdCompressor(level) # type: ignore
self._compressor = ctx.stream_writer(self._buf)
self.flushed = False