def __init__(self, data=None, fp=None, length=-1):
assert bool(data is not None) ^ bool(fp)
if length == -1:
if data is not None:
length = len(data)
else:
length = get_size(fp) # can be -1
# We allow writer reuse, but if we're working with a stream, we cannot
# seek. Copy the data to a tempfile.
if fp and not can_seek(fp):
newfp = SpooledTemporaryFile(MAX_INMEMORY_SIZE)
sendfile(newfp, fp)
length = newfp.tell()
newfp.seek(0)
fp = newfp
self.data = data
self.fp = fp
self.fpreads = 0 # keep track of fp usage
self.length = length
assert length >= 0
self.use_tempfile = length > MAX_INMEMORY_SIZE
def _encrypt_with_none(self):
if self.fp:
# Return a new file so they're not closing ours.
try:
fileno = self.fp.fileno()
except UnsupportedOperation:
newfp = SpooledTemporaryFile(MAX_INMEMORY_SIZE)
sendfile(newfp, self.fp)
newfp.seek(0)
return newfp
else:
return fdopen(fileno, "rb")
else:
# For no encryption, passing around a BytesIO is no extra effort if
# the data already was a string.
return BytesIO(self.data)