From 9af9d8ae35157f2b854be0168bc8dc43d6e0bf1b Mon Sep 17 00:00:00 2001 From: Brian Warner Date: Mon, 23 Feb 2009 18:58:37 -0700 Subject: [PATCH] immutable/layout.py: wrap to 80 cols, no functional changes --- src/allmydata/immutable/layout.py | 50 +++++++++++++++++-------------- 1 file changed, 28 insertions(+), 22 deletions(-) diff --git a/src/allmydata/immutable/layout.py b/src/allmydata/immutable/layout.py index d1e3ef0f..68555624 100644 --- a/src/allmydata/immutable/layout.py +++ b/src/allmydata/immutable/layout.py @@ -8,25 +8,26 @@ from allmydata.util.assertutil import precondition from allmydata.storage.server import si_b2a class LayoutInvalid(Exception): - """ There is something wrong with these bytes so they can't be interpreted as the kind of - immutable file that I know how to download. """ + """ There is something wrong with these bytes so they can't be + interpreted as the kind of immutable file that I know how to download.""" pass class RidiculouslyLargeURIExtensionBlock(LayoutInvalid): - """ When downloading a file, the length of the URI Extension Block was given as >= 2**32. - This means the share data must have been corrupted, or else the original uploader of the - file wrote a ridiculous value into the URI Extension Block length. """ + """ When downloading a file, the length of the URI Extension Block was + given as >= 2**32. This means the share data must have been corrupted, or + else the original uploader of the file wrote a ridiculous value into the + URI Extension Block length.""" pass class ShareVersionIncompatible(LayoutInvalid): - """ When downloading a share, its format was not one of the formats we know how to - parse. """ + """ When downloading a share, its format was not one of the formats we + know how to parse.""" pass """ -Share data is written in a file. At the start of the file, there is a series of four-byte -big-endian offset values, which indicate where each section starts. Each offset is measured from -the beginning of the share data. +Share data is written in a file. At the start of the file, there is a series +of four-byte big-endian offset values, which indicate where each section +starts. Each offset is measured from the beginning of the share data. 0x00: version number (=00 00 00 01) 0x04: block size # See Footnote 1 below. @@ -286,8 +287,9 @@ class ReadBucketProxy: return self._reprstr def _start_if_needed(self): - """ Returns a deferred that will be fired when I'm ready to return data, or errbacks if - the starting (header reading and parsing) process fails.""" + """ Returns a deferred that will be fired when I'm ready to return + data, or errbacks if the starting (header reading and parsing) + process fails.""" if not self._started: self._start() return self._ready.when_fired() @@ -297,8 +299,9 @@ class ReadBucketProxy: # TODO: for small shares, read the whole bucket in _start() d = self._fetch_header() d.addCallback(self._parse_offsets) - # XXX The following two callbacks implement a slightly faster/nicer way to get the ueb - # and sharehashtree, but it requires that the storage server be >= v1.3.0. + # XXX The following two callbacks implement a slightly faster/nicer + # way to get the ueb and sharehashtree, but it requires that the + # storage server be >= v1.3.0. # d.addCallback(self._fetch_sharehashtree_and_ueb) # d.addCallback(self._parse_sharehashtree_and_ueb) def _fail_waiters(f): @@ -347,7 +350,8 @@ class ReadBucketProxy: def _fetch_sharehashtree_and_ueb(self, offsets): sharehashtree_size = offsets['uri_extension'] - offsets['share_hashes'] - return self._read(offsets['share_hashes'], self.MAX_UEB_SIZE+sharehashtree_size) + return self._read(offsets['share_hashes'], + self.MAX_UEB_SIZE+sharehashtree_size) def _parse_sharehashtree_and_ueb(self, data): sharehashtree_size = self._offsets['uri_extension'] - self._offsets['share_hashes'] @@ -422,8 +426,9 @@ class ReadBucketProxy: return d def _get_share_hashes_the_old_way(self): - """ Tahoe storage servers < v1.3.0 would return an error if you tried to read past the - end of the share, so we need to use the offset and read just that much.""" + """ Tahoe storage servers < v1.3.0 would return an error if you tried + to read past the end of the share, so we need to use the offset and + read just that much.""" offset = self._offsets['share_hashes'] size = self._offsets['uri_extension'] - offset if size % (2+HASH_SIZE) != 0: @@ -442,8 +447,9 @@ class ReadBucketProxy: return d def _get_uri_extension_the_old_way(self, unused=None): - """ Tahoe storage servers < v1.3.0 would return an error if you tried to read past the - end of the share, so we need to fetch the UEB size and then read just that much.""" + """ Tahoe storage servers < v1.3.0 would return an error if you tried + to read past the end of the share, so we need to fetch the UEB size + and then read just that much.""" offset = self._offsets['uri_extension'] d = self._read(offset, self._fieldsize) def _got_length(data): @@ -451,9 +457,9 @@ class ReadBucketProxy: raise LayoutInvalid("not enough bytes to encode URI length -- should be %d bytes long, not %d " % (self._fieldsize, len(data),)) length = struct.unpack(self._fieldstruct, data)[0] if length >= 2**31: - # URI extension blocks are around 419 bytes long, so this must be corrupted. - # Anyway, the foolscap interface schema for "read" will not allow >= 2**31 bytes - # length. + # URI extension blocks are around 419 bytes long, so this + # must be corrupted. Anyway, the foolscap interface schema + # for "read" will not allow >= 2**31 bytes length. raise RidiculouslyLargeURIExtensionBlock(length) return self._read(offset+self._fieldsize, length) -- 2.45.2