From: Zooko O'Whielacronx Date: Sat, 10 Nov 2007 01:06:25 +0000 (-0700) Subject: mutable.py: fix padding/shape-of-input-data to zfec X-Git-Tag: allmydata-tahoe-0.7.0~229 X-Git-Url: https://git.rkrishnan.org/(%5B%5E?a=commitdiff_plain;h=f6451deb74bc91b5c2dee38007e66d11ac802403;p=tahoe-lafs%2Ftahoe-lafs.git mutable.py: fix padding/shape-of-input-data to zfec --- diff --git a/src/allmydata/mutable.py b/src/allmydata/mutable.py index fe866d37..cb80557f 100644 --- a/src/allmydata/mutable.py +++ b/src/allmydata/mutable.py @@ -892,27 +892,24 @@ class Publish: # now apply FEC self.MAX_SEGMENT_SIZE = 1024*1024 data_length = len(crypttext) - if len(crypttext) < 10: - # TODO: FEC doesn't handle short (or empty) strings very well, so - # give it something longer and we'll trim the results later. For - # some reason I suspect the lower limit is k**2 - crypttext = crypttext + "\x00"*(10-len(crypttext)) segment_size = min(self.MAX_SEGMENT_SIZE, len(crypttext)) # this must be a multiple of self.required_shares segment_size = mathutil.next_multiple(segment_size, required_shares) - self.num_segments = mathutil.div_ceil(len(crypttext), segment_size) - assert self.num_segments == 1 # SDMF restrictions + if segment_size: + self.num_segments = mathutil.div_ceil(len(crypttext), segment_size) + else: + self.num_segments = 0 + assert self.num_segments in [0, 1,] # SDMF restrictions fec = codec.CRSEncoder() fec.set_params(segment_size, required_shares, total_shares) piece_size = fec.get_block_size() - crypttext_pieces = [] - for offset in range(0, len(crypttext), piece_size): + crypttext_pieces = [None] * required_shares + for i in range(len(crypttext_pieces)): + offset = i * piece_size piece = crypttext[offset:offset+piece_size] - if len(piece) < piece_size: - pad_size = piece_size - len(piece) - piece = piece + "\x00"*pad_size - crypttext_pieces.append(piece) + piece = piece + "\x00"*(piece_size - len(piece)) # padding + crypttext_pieces[i] = piece assert len(piece) == piece_size d = fec.encode(crypttext_pieces)