def create_compressed_fs(progress, source, target, block_size=65536, preamble=PREAMBLE, level=9):
size = os.path.getsize(source)
num_blocks = int(math.ceil(size / block_size))
header = HEADER.pack(preamble, block_size, num_blocks)
with open(target, 'wb') as target:
target.write(header)
current = len(header) + OFFSET.size * (num_blocks + 1)
target.seek(current)
offsets = [current]
progress.update(0)
with open(source, 'rb') as source:
for i in range(1, num_blocks + 1):
if progress.condition('cancel'):
return
progress.update(i / num_blocks * 100)
uncompressed = source.read(block_size)
if len(uncompressed) < block_size:
uncompressed += '\x00' * (block_size - len(uncompressed))
assert len(uncompressed) == block_size
compressed = zlib.compress(uncompressed, level)
target.write(compressed)
current += len(compressed)
offsets.append(current)
target.seek(len(header))
for offset in offsets:
target.write(OFFSET.pack(offset))
def extract_compressed_fs(progress, source, target):
with open(source, 'rb') as source:
num_blocks = HEADER.unpack(source.read(HEADER.size))[2]
offsets = [OFFSET.unpack(source.read(OFFSET.size))[0] for i in range(num_blocks + 1)]
progress.update(0)
with open(target, 'wb') as target:
for i, offset in enumerate(offsets[:-1]):
if progress.condition('cancel'):
return
progress.update((i + 1) / num_blocks * 100)
target.write(zlib.decompress(source.read(offsets[i + 1] - offset)))
def mkisofs(progress, *arguments):
process = subprocess.Popen([_mkisofs] + list(arguments), stderr=subprocess.PIPE)
while process.poll() is None:
if progress.condition('cancel'):
process.kill()
return
else:
line = process.stderr.readline()
match = _MKISOFS_PERCENTAGE.search(line)
if match:
progress.update(float(match.group(1)))
progress.update(100)
if process.returncode != 0:
progress.condition('error').activate()
def mkisofs(progress, *arguments):
process = subprocess.Popen([_mkisofs] + list(arguments),
stderr=subprocess.PIPE)
while process.poll() is None:
if progress.condition('cancel'):
process.kill()
return
else:
line = process.stderr.readline()
match = _MKISOFS_PERCENTAGE.search(line)
if match:
progress.update(float(match.group(1)))
progress.update(100)
if process.returncode != 0:
progress.condition('error').activate()