Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Coping with large solid archives #5

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Coping with large solid archives #5

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
41 changes: 21 additions & 20 deletions py7zlib.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -561,50 +561,51 @@ def _read_copy(self, coder, input):
input = self._file.read(self.uncompressed)
return input[self._start:self._start+self.size]

def _read_from_decompressor(self, coder, decompressor, input, checkremaining=False, with_cache=False):
data = ''
def _read_from_decompressor(self, coder, decompressor, input, checkremaining=False):
idx = 0
cnt = 0
self._file.seek(self._src_start)
properties = coder.get('properties', None)
if properties:
decompressor.decompress(properties)
total = self.compressed
if not input and total is None:
remaining = self._start+self.size
remaining_preroll = self._start
tmp = ''
while remaining_preroll > 0:
data = self._file.read(READ_BLOCKSIZE)
if checkremaining:
tmp = decompressor.decompress(data, remaining_preroll + self.size )
else:
tmp = decompressor.decompress(data)
assert len(tmp) > 0
remaining_preroll -= len(tmp)

out = BytesIO()
cache = getattr(self._folder, '_decompress_cache', None)
if cache is not None:
data, pos, decompressor = cache
out.write(data)
remaining -= len(data)
self._file.seek(pos)
else:
self._file.seek(self._src_start)
checkremaining = checkremaining and not self._folder.solid
out.write( tmp[len(tmp) + remaining_preroll ::] )

remaining = self.size + remaining_preroll
while remaining > 0:
data = self._file.read(READ_BLOCKSIZE)
if checkremaining or (with_cache and len(data) < READ_BLOCKSIZE):
if checkremaining:
tmp = decompressor.decompress(data, remaining)
else:
tmp = decompressor.decompress(data)
assert len(tmp) > 0
out.write(tmp)
remaining -= len(tmp)

data = out.getvalue()
if with_cache and self._folder.solid:
# don't decompress start of solid archive for next file
# TODO: limit size of cached data
self._folder._decompress_cache = (data, self._file.tell(), decompressor)
out.seek(0)
return out.read(self.size)
else:
data = ''
if not input:
self._file.seek(self._src_start)
input = self._file.read(total)
if checkremaining:
data = decompressor.decompress(input, self._start+self.size)
else:
data = decompressor.decompress(input)
return data[self._start:self._start+self.size]
return data[self._start:self._start+self.size]

def _read_lzma(self, coder, input):
dec = pylzma.decompressobj(maxlength=self._start+self.size)
Expand Down