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# Copyright (C) 2008, 2009 Canonical Ltd
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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"""Core compression logic for compressing streams of related files."""
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from itertools import izip
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from cStringIO import StringIO
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from bzrlib.graph import Graph
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from bzrlib.knit import _DirectPackAccess
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from bzrlib.btree_index import BTreeBuilder
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from bzrlib.lru_cache import LRUSizeCache
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from bzrlib.tsort import topo_sort
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from bzrlib.versionedfile import (
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ChunkedContentFactory,
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FulltextContentFactory,
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_USE_LZMA = False and (pylzma is not None)
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# osutils.sha_string('')
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_null_sha1 = 'da39a3ee5e6b4b0d3255bfef95601890afd80709'
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def sort_gc_optimal(parent_map):
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"""Sort and group the keys in parent_map into groupcompress order.
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groupcompress is defined (currently) as reverse-topological order, grouped
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:return: A sorted-list of keys
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# groupcompress ordering is approximately reverse topological,
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# properly grouped by file-id.
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for item in parent_map.iteritems():
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if isinstance(key, str) or len(key) == 1:
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per_prefix_map[prefix].append(item)
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per_prefix_map[prefix] = [item]
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for prefix in sorted(per_prefix_map):
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present_keys.extend(reversed(topo_sort(per_prefix_map[prefix])))
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# The max zlib window size is 32kB, so if we set 'max_size' output of the
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# decompressor to the requested bytes + 32kB, then we should guarantee
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# num_bytes coming out.
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_ZLIB_DECOMP_WINDOW = 32*1024
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class GroupCompressBlock(object):
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"""An object which maintains the internal structure of the compressed data.
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This tracks the meta info (start of text, length, type, etc.)
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# Group Compress Block v1 Zlib
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GCB_HEADER = 'gcb1z\n'
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# Group Compress Block v1 Lzma
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GCB_LZ_HEADER = 'gcb1l\n'
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GCB_KNOWN_HEADERS = (GCB_HEADER, GCB_LZ_HEADER)
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# map by key? or just order in file?
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self._compressor_name = None
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self._z_content = None
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self._z_content_decompressor = None
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self._z_content_length = None
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self._content_length = None
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# This is the maximum number of bytes this object will reference if
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# everything is decompressed. However, if we decompress less than
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# everything... (this would cause some problems for LRUSizeCache)
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return self._content_length + self._z_content_length
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def _ensure_content(self, num_bytes=None):
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"""Make sure that content has been expanded enough.
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:param num_bytes: Ensure that we have extracted at least num_bytes of
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content. If None, consume everything
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# TODO: If we re-use the same content block at different times during
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# get_record_stream(), it is possible that the first pass will
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# get inserted, triggering an extract/_ensure_content() which
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# will get rid of _z_content. And then the next use of the block
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# will try to access _z_content (to send it over the wire), and
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# fail because it is already extracted. Consider never releasing
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# _z_content because of this.
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if num_bytes is None:
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num_bytes = self._content_length
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elif (self._content_length is not None
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and num_bytes > self._content_length):
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raise AssertionError(
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'requested num_bytes (%d) > content length (%d)'
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% (num_bytes, self._content_length))
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# Expand the content if required
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if self._content is None:
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if self._z_content is None:
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raise AssertionError('No content to decompress')
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if self._z_content == '':
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elif self._compressor_name == 'lzma':
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# We don't do partial lzma decomp yet
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self._content = pylzma.decompress(self._z_content)
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elif self._compressor_name == 'zlib':
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# Start a zlib decompressor
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if num_bytes is None:
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self._content = zlib.decompress(self._z_content)
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self._z_content_decompressor = zlib.decompressobj()
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# Seed the decompressor with the uncompressed bytes, so
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# that the rest of the code is simplified
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self._content = self._z_content_decompressor.decompress(
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self._z_content, num_bytes + _ZLIB_DECOMP_WINDOW)
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raise AssertionError('Unknown compressor: %r'
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% self._compressor_name)
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# Any bytes remaining to be decompressed will be in the decompressors
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# Do we have enough bytes already?
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if num_bytes is not None and len(self._content) >= num_bytes:
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if num_bytes is None and self._z_content_decompressor is None:
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# We must have already decompressed everything
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# If we got this far, and don't have a decompressor, something is wrong
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if self._z_content_decompressor is None:
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raise AssertionError(
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'No decompressor to decompress %d bytes' % num_bytes)
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remaining_decomp = self._z_content_decompressor.unconsumed_tail
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if num_bytes is None:
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# We don't know how much is left, but we'll decompress it all
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self._content += self._z_content_decompressor.decompress(
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# Note: There's what I consider a bug in zlib.decompressobj
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# If you pass back in the entire unconsumed_tail, only
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# this time you don't pass a max-size, it doesn't
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# change the unconsumed_tail back to None/''.
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# However, we know we are done with the whole stream
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self._z_content_decompressor = None
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# XXX: Why is this the only place in this routine we set this?
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self._content_length = len(self._content)
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if not remaining_decomp:
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raise AssertionError('Nothing left to decompress')
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needed_bytes = num_bytes - len(self._content)
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# We always set max_size to 32kB over the minimum needed, so that
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# zlib will give us as much as we really want.
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# TODO: If this isn't good enough, we could make a loop here,
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# that keeps expanding the request until we get enough
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self._content += self._z_content_decompressor.decompress(
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remaining_decomp, needed_bytes + _ZLIB_DECOMP_WINDOW)
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if len(self._content) < num_bytes:
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raise AssertionError('%d bytes wanted, only %d available'
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% (num_bytes, len(self._content)))
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if not self._z_content_decompressor.unconsumed_tail:
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# The stream is finished
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self._z_content_decompressor = None
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def _parse_bytes(self, bytes, pos):
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"""Read the various lengths from the header.
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This also populates the various 'compressed' buffers.
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:return: The position in bytes just after the last newline
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# At present, we have 2 integers for the compressed and uncompressed
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# content. In base10 (ascii) 14 bytes can represent > 1TB, so to avoid
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# checking too far, cap the search to 14 bytes.
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pos2 = bytes.index('\n', pos, pos + 14)
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self._z_content_length = int(bytes[pos:pos2])
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pos2 = bytes.index('\n', pos, pos + 14)
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self._content_length = int(bytes[pos:pos2])
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if len(bytes) != (pos + self._z_content_length):
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# XXX: Define some GCCorrupt error ?
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raise AssertionError('Invalid bytes: (%d) != %d + %d' %
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(len(bytes), pos, self._z_content_length))
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self._z_content = bytes[pos:]
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def from_bytes(cls, bytes):
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if bytes[:6] not in cls.GCB_KNOWN_HEADERS:
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raise ValueError('bytes did not start with any of %r'
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% (cls.GCB_KNOWN_HEADERS,))
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# XXX: why not testing the whole header ?
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out._compressor_name = 'zlib'
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elif bytes[4] == 'l':
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out._compressor_name = 'lzma'
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raise ValueError('unknown compressor: %r' % (bytes,))
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out._parse_bytes(bytes, 6)
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def extract(self, key, start, end, sha1=None):
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"""Extract the text for a specific key.
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:param key: The label used for this content
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:param sha1: TODO (should we validate only when sha1 is supplied?)
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:return: The bytes for the content
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if start == end == 0:
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self._ensure_content(end)
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# The bytes are 'f' or 'd' for the type, then a variable-length
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# base128 integer for the content size, then the actual content
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# We know that the variable-length integer won't be longer than 5
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# bytes (it takes 5 bytes to encode 2^32)
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c = self._content[start]
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raise ValueError('Unknown content control code: %s'
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content_len, len_len = decode_base128_int(
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self._content[start + 1:start + 6])
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content_start = start + 1 + len_len
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if end != content_start + content_len:
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raise ValueError('end != len according to field header'
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' %s != %s' % (end, content_start + content_len))
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bytes = self._content[content_start:end]
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bytes = apply_delta_to_source(self._content, content_start, end)
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def set_content(self, content):
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"""Set the content of this block."""
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self._content_length = len(content)
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self._content = content
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self._z_content = None
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"""Encode the information into a byte stream."""
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compress = zlib.compress
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compress = pylzma.compress
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if self._z_content is None:
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if self._content is None:
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raise AssertionError('Nothing to compress')
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self._z_content = compress(self._content)
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self._z_content_length = len(self._z_content)
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header = self.GCB_LZ_HEADER
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header = self.GCB_HEADER
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'%d\n%d\n' % (self._z_content_length, self._content_length),
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return ''.join(chunks)
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class _LazyGroupCompressFactory(object):
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"""Yield content from a GroupCompressBlock on demand."""
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def __init__(self, key, parents, manager, start, end, first):
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"""Create a _LazyGroupCompressFactory
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:param key: The key of just this record
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:param parents: The parents of this key (possibly None)
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:param gc_block: A GroupCompressBlock object
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:param start: Offset of the first byte for this record in the
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:param end: Offset of the byte just after the end of this record
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(ie, bytes = content[start:end])
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:param first: Is this the first Factory for the given block?
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self.parents = parents
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# Note: This attribute coupled with Manager._factories creates a
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# reference cycle. Perhaps we would rather use a weakref(), or
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# find an appropriate time to release the ref. After the first
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# get_bytes_as call? After Manager.get_record_stream() returns
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self._manager = manager
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self.storage_kind = 'groupcompress-block'
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self.storage_kind = 'groupcompress-block-ref'
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return '%s(%s, first=%s)' % (self.__class__.__name__,
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self.key, self._first)
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def get_bytes_as(self, storage_kind):
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if storage_kind == self.storage_kind:
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# wire bytes, something...
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return self._manager._wire_bytes()
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if storage_kind in ('fulltext', 'chunked'):
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if self._bytes is None:
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# Grab and cache the raw bytes for this entry
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# and break the ref-cycle with _manager since we don't need it
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self._manager._prepare_for_extract()
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block = self._manager._block
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self._bytes = block.extract(self.key, self._start, self._end)
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# There are code paths that first extract as fulltext, and then
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# extract as storage_kind (smart fetch). So we don't break the
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# refcycle here, but instead in manager.get_record_stream()
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# self._manager = None
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if storage_kind == 'fulltext':
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raise errors.UnavailableRepresentation(self.key, storage_kind,
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class _LazyGroupContentManager(object):
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"""This manages a group of _LazyGroupCompressFactory objects."""
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def __init__(self, block):
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# We need to preserve the ordering
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def add_factory(self, key, parents, start, end):
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if not self._factories:
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# Note that this creates a reference cycle....
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factory = _LazyGroupCompressFactory(key, parents, self,
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start, end, first=first)
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# max() works here, but as a function call, doing a compare seems to be
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# significantly faster, timeit says 250ms for max() and 100ms for the
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if end > self._last_byte:
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self._last_byte = end
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self._factories.append(factory)
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def get_record_stream(self):
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"""Get a record for all keys added so far."""
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for factory in self._factories:
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# Break the ref-cycle
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factory._bytes = None
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factory._manager = None
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# TODO: Consider setting self._factories = None after the above loop,
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# as it will break the reference cycle
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def _trim_block(self, last_byte):
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"""Create a new GroupCompressBlock, with just some of the content."""
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# None of the factories need to be adjusted, because the content is
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# located in an identical place. Just that some of the unreferenced
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# trailing bytes are stripped
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trace.mutter('stripping trailing bytes from groupcompress block'
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' %d => %d', self._block._content_length, last_byte)
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new_block = GroupCompressBlock()
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self._block._ensure_content(last_byte)
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new_block.set_content(self._block._content[:last_byte])
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self._block = new_block
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def _rebuild_block(self):
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"""Create a new GroupCompressBlock with only the referenced texts."""
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compressor = GroupCompressor()
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old_length = self._block._content_length
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for factory in self._factories:
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bytes = factory.get_bytes_as('fulltext')
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(found_sha1, start_point, end_point,
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type) = compressor.compress(factory.key, bytes, factory.sha1)
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# Now update this factory with the new offsets, etc
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factory.sha1 = found_sha1
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factory._start = start_point
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factory._end = end_point
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self._last_byte = end_point
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new_block = compressor.flush()
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# TODO: Should we check that new_block really *is* smaller than the old
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# block? It seems hard to come up with a method that it would
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# expand, since we do full compression again. Perhaps based on a
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# request that ends up poorly ordered?
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delta = time.time() - tstart
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self._block = new_block
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trace.mutter('creating new compressed block on-the-fly in %.3fs'
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' %d bytes => %d bytes', delta, old_length,
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self._block._content_length)
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def _prepare_for_extract(self):
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"""A _LazyGroupCompressFactory is about to extract to fulltext."""
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# We expect that if one child is going to fulltext, all will be. This
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# helps prevent all of them from extracting a small amount at a time.
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# Which in itself isn't terribly expensive, but resizing 2MB 32kB at a
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# time (self._block._content) is a little expensive.
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self._block._ensure_content(self._last_byte)
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def _check_rebuild_block(self):
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"""Check to see if our block should be repacked."""
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for factory in self._factories:
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total_bytes_used += factory._end - factory._start
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last_byte_used = max(last_byte_used, factory._end)
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# If we are using most of the bytes from the block, we have nothing
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# else to check (currently more that 1/2)
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if total_bytes_used * 2 >= self._block._content_length:
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# Can we just strip off the trailing bytes? If we are going to be
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# transmitting more than 50% of the front of the content, go ahead
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if total_bytes_used * 2 > last_byte_used:
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self._trim_block(last_byte_used)
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# We are using a small amount of the data, and it isn't just packed
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# nicely at the front, so rebuild the content.
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# Note: This would be *nicer* as a strip-data-from-group, rather than
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# building it up again from scratch
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# It might be reasonable to consider the fulltext sizes for
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# different bits when deciding this, too. As you may have a small
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# fulltext, and a trivial delta, and you are just trading around
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# for another fulltext. If we do a simple 'prune' you may end up
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# expanding many deltas into fulltexts, as well.
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# If we build a cheap enough 'strip', then we could try a strip,
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# if that expands the content, we then rebuild.
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self._rebuild_block()
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def _wire_bytes(self):
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"""Return a byte stream suitable for transmitting over the wire."""
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self._check_rebuild_block()
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# The outer block starts with:
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# 'groupcompress-block\n'
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# <length of compressed key info>\n
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# <length of uncompressed info>\n
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# <length of gc block>\n
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lines = ['groupcompress-block\n']
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# The minimal info we need is the key, the start offset, and the
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# parents. The length and type are encoded in the record itself.
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# However, passing in the other bits makes it easier. The list of
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# keys, and the start offset, the length
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# 1 line with parents, '' for ()
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# 1 line for start offset
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# 1 line for end byte
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for factory in self._factories:
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key_bytes = '\x00'.join(factory.key)
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parents = factory.parents
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parent_bytes = 'None:'
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parent_bytes = '\t'.join('\x00'.join(key) for key in parents)
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record_header = '%s\n%s\n%d\n%d\n' % (
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key_bytes, parent_bytes, factory._start, factory._end)
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header_lines.append(record_header)
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# TODO: Can we break the refcycle at this point and set
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# factory._manager = None?
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header_bytes = ''.join(header_lines)
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header_bytes_len = len(header_bytes)
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z_header_bytes = zlib.compress(header_bytes)
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z_header_bytes_len = len(z_header_bytes)
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block_bytes = self._block.to_bytes()
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lines.append('%d\n%d\n%d\n' % (z_header_bytes_len, header_bytes_len,
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lines.append(z_header_bytes)
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lines.append(block_bytes)
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del z_header_bytes, block_bytes
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return ''.join(lines)
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def from_bytes(cls, bytes):
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# TODO: This does extra string copying, probably better to do it a
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(storage_kind, z_header_len, header_len,
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block_len, rest) = bytes.split('\n', 4)
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if storage_kind != 'groupcompress-block':
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raise ValueError('Unknown storage kind: %s' % (storage_kind,))
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z_header_len = int(z_header_len)
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if len(rest) < z_header_len:
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raise ValueError('Compressed header len shorter than all bytes')
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z_header = rest[:z_header_len]
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header_len = int(header_len)
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header = zlib.decompress(z_header)
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if len(header) != header_len:
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raise ValueError('invalid length for decompressed bytes')
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block_len = int(block_len)
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if len(rest) != z_header_len + block_len:
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raise ValueError('Invalid length for block')
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block_bytes = rest[z_header_len:]
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# So now we have a valid GCB, we just need to parse the factories that
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header_lines = header.split('\n')
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last = header_lines.pop()
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raise ValueError('header lines did not end with a trailing'
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if len(header_lines) % 4 != 0:
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raise ValueError('The header was not an even multiple of 4 lines')
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block = GroupCompressBlock.from_bytes(block_bytes)
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for start in xrange(0, len(header_lines), 4):
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key = tuple(header_lines[start].split('\x00'))
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parents_line = header_lines[start+1]
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if parents_line == 'None:':
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parents = tuple([tuple(segment.split('\x00'))
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for segment in parents_line.split('\t')
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start_offset = int(header_lines[start+2])
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end_offset = int(header_lines[start+3])
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result.add_factory(key, parents, start_offset, end_offset)
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def network_block_to_records(storage_kind, bytes, line_end):
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if storage_kind != 'groupcompress-block':
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raise ValueError('Unknown storage kind: %s' % (storage_kind,))
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manager = _LazyGroupContentManager.from_bytes(bytes)
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return manager.get_record_stream()
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class _CommonGroupCompressor(object):
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"""Create a GroupCompressor."""
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self.labels_deltas = {}
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self._delta_index = None # Set by the children
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self._block = GroupCompressBlock()
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def compress(self, key, bytes, expected_sha, nostore_sha=None, soft=False):
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"""Compress lines with label key.
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:param key: A key tuple. It is stored in the output
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for identification of the text during decompression. If the last
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element is 'None' it is replaced with the sha1 of the text -
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:param bytes: The bytes to be compressed
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:param expected_sha: If non-None, the sha the lines are believed to
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have. During compression the sha is calculated; a mismatch will
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:param nostore_sha: If the computed sha1 sum matches, we will raise
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ExistingContent rather than adding the text.
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:param soft: Do a 'soft' compression. This means that we require larger
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ranges to match to be considered for a copy command.
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:return: The sha1 of lines, the start and end offsets in the delta, and
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the type ('fulltext' or 'delta').
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:seealso VersionedFiles.add_lines:
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if not bytes: # empty, like a dir entry, etc
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if nostore_sha == _null_sha1:
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raise errors.ExistingContent()
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return _null_sha1, 0, 0, 'fulltext'
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# we assume someone knew what they were doing when they passed it in
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if expected_sha is not None:
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sha1 = osutils.sha_string(bytes)
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if nostore_sha is not None:
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if sha1 == nostore_sha:
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raise errors.ExistingContent()
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key = key[:-1] + ('sha1:' + sha1,)
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start, end, type = self._compress(key, bytes, len(bytes) / 2, soft)
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return sha1, start, end, type
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def _compress(self, key, bytes, max_delta_size, soft=False):
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"""Compress lines with label key.
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:param key: A key tuple. It is stored in the output for identification
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of the text during decompression.
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:param bytes: The bytes to be compressed
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:param max_delta_size: The size above which we issue a fulltext instead
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:param soft: Do a 'soft' compression. This means that we require larger
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ranges to match to be considered for a copy command.
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:return: The sha1 of lines, the start and end offsets in the delta, and
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the type ('fulltext' or 'delta').
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raise NotImplementedError(self._compress)
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def extract(self, key):
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"""Extract a key previously added to the compressor.
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:param key: The key to extract.
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:return: An iterable over bytes and the sha1.
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(start_byte, start_chunk, end_byte, end_chunk) = self.labels_deltas[key]
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delta_chunks = self.chunks[start_chunk:end_chunk]
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stored_bytes = ''.join(delta_chunks)
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if stored_bytes[0] == 'f':
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fulltext_len, offset = decode_base128_int(stored_bytes[1:10])
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data_len = fulltext_len + 1 + offset
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if data_len != len(stored_bytes):
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raise ValueError('Index claimed fulltext len, but stored bytes'
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% (len(stored_bytes), data_len))
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bytes = stored_bytes[offset + 1:]
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# XXX: This is inefficient at best
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source = ''.join(self.chunks[:start_chunk])
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if stored_bytes[0] != 'd':
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raise ValueError('Unknown content kind, bytes claim %s'
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% (stored_bytes[0],))
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delta_len, offset = decode_base128_int(stored_bytes[1:10])
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data_len = delta_len + 1 + offset
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if data_len != len(stored_bytes):
677
raise ValueError('Index claimed delta len, but stored bytes'
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% (len(stored_bytes), data_len))
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bytes = apply_delta(source, stored_bytes[offset + 1:])
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bytes_sha1 = osutils.sha_string(bytes)
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return bytes, bytes_sha1
685
"""Finish this group, creating a formatted stream.
687
After calling this, the compressor should no longer be used
689
content = ''.join(self.chunks)
691
self._delta_index = None
692
self._block.set_content(content)
696
"""Call this if you want to 'revoke' the last compression.
698
After this, the data structures will be rolled back, but you cannot do
701
self._delta_index = None
702
del self.chunks[self._last[0]:]
703
self.endpoint = self._last[1]
707
"""Return the overall compression ratio."""
708
return float(self.input_bytes) / float(self.endpoint)
711
class PythonGroupCompressor(_CommonGroupCompressor):
714
"""Create a GroupCompressor.
716
Used only if the pyrex version is not available.
718
super(PythonGroupCompressor, self).__init__()
719
self._delta_index = LinesDeltaIndex([])
720
# The actual content is managed by LinesDeltaIndex
721
self.chunks = self._delta_index.lines
723
def _compress(self, key, bytes, max_delta_size, soft=False):
724
"""see _CommonGroupCompressor._compress"""
725
input_len = len(bytes)
726
new_lines = osutils.split_lines(bytes)
727
out_lines, index_lines = self._delta_index.make_delta(
728
new_lines, bytes_length=input_len, soft=soft)
729
delta_length = sum(map(len, out_lines))
730
if delta_length > max_delta_size:
731
# The delta is longer than the fulltext, insert a fulltext
733
out_lines = ['f', encode_base128_int(input_len)]
734
out_lines.extend(new_lines)
735
index_lines = [False, False]
736
index_lines.extend([True] * len(new_lines))
738
# this is a worthy delta, output it
741
# Update the delta_length to include those two encoded integers
742
out_lines[1] = encode_base128_int(delta_length)
744
start = self.endpoint
745
chunk_start = len(self.chunks)
746
self._delta_index.extend_lines(out_lines, index_lines)
747
self.endpoint = self._delta_index.endpoint
748
self.input_bytes += input_len
749
chunk_end = len(self.chunks)
750
self.labels_deltas[key] = (start, chunk_start,
751
self.endpoint, chunk_end)
752
return start, self.endpoint, type
755
class PyrexGroupCompressor(_CommonGroupCompressor):
756
"""Produce a serialised group of compressed texts.
758
It contains code very similar to SequenceMatcher because of having a similar
759
task. However some key differences apply:
760
- there is no junk, we want a minimal edit not a human readable diff.
761
- we don't filter very common lines (because we don't know where a good
762
range will start, and after the first text we want to be emitting minmal
764
- we chain the left side, not the right side
765
- we incrementally update the adjacency matrix as new lines are provided.
766
- we look for matches in all of the left side, so the routine which does
767
the analagous task of find_longest_match does not need to filter on the
772
super(PyrexGroupCompressor, self).__init__()
773
self._delta_index = DeltaIndex()
775
def _compress(self, key, bytes, max_delta_size, soft=False):
776
"""see _CommonGroupCompressor._compress"""
777
input_len = len(bytes)
778
# By having action/label/sha1/len, we can parse the group if the index
779
# was ever destroyed, we have the key in 'label', we know the final
780
# bytes are valid from sha1, and we know where to find the end of this
781
# record because of 'len'. (the delta record itself will store the
782
# total length for the expanded record)
783
# 'len: %d\n' costs approximately 1% increase in total data
784
# Having the labels at all costs us 9-10% increase, 38% increase for
785
# inventory pages, and 5.8% increase for text pages
786
# new_chunks = ['label:%s\nsha1:%s\n' % (label, sha1)]
787
if self._delta_index._source_offset != self.endpoint:
788
raise AssertionError('_source_offset != endpoint'
789
' somehow the DeltaIndex got out of sync with'
791
delta = self._delta_index.make_delta(bytes, max_delta_size)
794
enc_length = encode_base128_int(len(bytes))
795
len_mini_header = 1 + len(enc_length)
796
self._delta_index.add_source(bytes, len_mini_header)
797
new_chunks = ['f', enc_length, bytes]
800
enc_length = encode_base128_int(len(delta))
801
len_mini_header = 1 + len(enc_length)
802
new_chunks = ['d', enc_length, delta]
803
self._delta_index.add_delta_source(delta, len_mini_header)
805
start = self.endpoint
806
chunk_start = len(self.chunks)
807
# Now output these bytes
808
self._output_chunks(new_chunks)
809
self.input_bytes += input_len
810
chunk_end = len(self.chunks)
811
self.labels_deltas[key] = (start, chunk_start,
812
self.endpoint, chunk_end)
813
if not self._delta_index._source_offset == self.endpoint:
814
raise AssertionError('the delta index is out of sync'
815
'with the output lines %s != %s'
816
% (self._delta_index._source_offset, self.endpoint))
817
return start, self.endpoint, type
819
def _output_chunks(self, new_chunks):
820
"""Output some chunks.
822
:param new_chunks: The chunks to output.
824
self._last = (len(self.chunks), self.endpoint)
825
endpoint = self.endpoint
826
self.chunks.extend(new_chunks)
827
endpoint += sum(map(len, new_chunks))
828
self.endpoint = endpoint
831
def make_pack_factory(graph, delta, keylength):
832
"""Create a factory for creating a pack based groupcompress.
834
This is only functional enough to run interface tests, it doesn't try to
835
provide a full pack environment.
837
:param graph: Store a graph.
838
:param delta: Delta compress contents.
839
:param keylength: How long should keys be.
841
def factory(transport):
846
graph_index = BTreeBuilder(reference_lists=ref_length,
847
key_elements=keylength)
848
stream = transport.open_write_stream('newpack')
849
writer = pack.ContainerWriter(stream.write)
851
index = _GCGraphIndex(graph_index, lambda:True, parents=parents,
852
add_callback=graph_index.add_nodes)
853
access = _DirectPackAccess({})
854
access.set_writer(writer, graph_index, (transport, 'newpack'))
855
result = GroupCompressVersionedFiles(index, access, delta)
856
result.stream = stream
857
result.writer = writer
862
def cleanup_pack_group(versioned_files):
863
versioned_files.writer.end()
864
versioned_files.stream.close()
867
class GroupCompressVersionedFiles(VersionedFiles):
868
"""A group-compress based VersionedFiles implementation."""
870
def __init__(self, index, access, delta=True):
871
"""Create a GroupCompressVersionedFiles object.
873
:param index: The index object storing access and graph data.
874
:param access: The access object storing raw data.
875
:param delta: Whether to delta compress or just entropy compress.
878
self._access = access
880
self._unadded_refs = {}
881
self._group_cache = LRUSizeCache(max_size=50*1024*1024)
882
self._fallback_vfs = []
884
def add_lines(self, key, parents, lines, parent_texts=None,
885
left_matching_blocks=None, nostore_sha=None, random_id=False,
887
"""Add a text to the store.
889
:param key: The key tuple of the text to add.
890
:param parents: The parents key tuples of the text to add.
891
:param lines: A list of lines. Each line must be a bytestring. And all
892
of them except the last must be terminated with \n and contain no
893
other \n's. The last line may either contain no \n's or a single
894
terminating \n. If the lines list does meet this constraint the add
895
routine may error or may succeed - but you will be unable to read
896
the data back accurately. (Checking the lines have been split
897
correctly is expensive and extremely unlikely to catch bugs so it
898
is not done at runtime unless check_content is True.)
899
:param parent_texts: An optional dictionary containing the opaque
900
representations of some or all of the parents of version_id to
901
allow delta optimisations. VERY IMPORTANT: the texts must be those
902
returned by add_lines or data corruption can be caused.
903
:param left_matching_blocks: a hint about which areas are common
904
between the text and its left-hand-parent. The format is
905
the SequenceMatcher.get_matching_blocks format.
906
:param nostore_sha: Raise ExistingContent and do not add the lines to
907
the versioned file if the digest of the lines matches this.
908
:param random_id: If True a random id has been selected rather than
909
an id determined by some deterministic process such as a converter
910
from a foreign VCS. When True the backend may choose not to check
911
for uniqueness of the resulting key within the versioned file, so
912
this should only be done when the result is expected to be unique
914
:param check_content: If True, the lines supplied are verified to be
915
bytestrings that are correctly formed lines.
916
:return: The text sha1, the number of bytes in the text, and an opaque
917
representation of the inserted version which can be provided
918
back to future add_lines calls in the parent_texts dictionary.
920
self._index._check_write_ok()
921
self._check_add(key, lines, random_id, check_content)
923
# The caller might pass None if there is no graph data, but kndx
924
# indexes can't directly store that, so we give them
925
# an empty tuple instead.
927
# double handling for now. Make it work until then.
928
length = sum(map(len, lines))
929
record = ChunkedContentFactory(key, parents, None, lines)
930
sha1 = list(self._insert_record_stream([record], random_id=random_id,
931
nostore_sha=nostore_sha))[0]
932
return sha1, length, None
934
def add_fallback_versioned_files(self, a_versioned_files):
935
"""Add a source of texts for texts not present in this knit.
937
:param a_versioned_files: A VersionedFiles object.
939
self._fallback_vfs.append(a_versioned_files)
941
def annotate(self, key):
942
"""See VersionedFiles.annotate."""
944
parent_map = self.get_parent_map([key])
946
raise errors.RevisionNotPresent(key, self)
947
if parent_map[key] is not None:
948
search = graph._make_breadth_first_searcher([key])
952
present, ghosts = search.next_with_ghosts()
953
except StopIteration:
956
parent_map = self.get_parent_map(keys)
959
parent_map = {key:()}
960
head_cache = _mod_graph.FrozenHeadsCache(graph)
962
reannotate = annotate.reannotate
963
for record in self.get_record_stream(keys, 'topological', True):
965
chunks = osutils.chunks_to_lines(record.get_bytes_as('chunked'))
966
parent_lines = [parent_cache[parent] for parent in parent_map[key]]
967
parent_cache[key] = list(
968
reannotate(parent_lines, chunks, key, None, head_cache))
969
return parent_cache[key]
971
def check(self, progress_bar=None):
972
"""See VersionedFiles.check()."""
974
for record in self.get_record_stream(keys, 'unordered', True):
975
record.get_bytes_as('fulltext')
977
def _check_add(self, key, lines, random_id, check_content):
978
"""check that version_id and lines are safe to add."""
980
if version_id is not None:
981
if osutils.contains_whitespace(version_id):
982
raise errors.InvalidRevisionId(version_id, self)
983
self.check_not_reserved_id(version_id)
984
# TODO: If random_id==False and the key is already present, we should
985
# probably check that the existing content is identical to what is
986
# being inserted, and otherwise raise an exception. This would make
987
# the bundle code simpler.
989
self._check_lines_not_unicode(lines)
990
self._check_lines_are_lines(lines)
992
def get_parent_map(self, keys):
993
"""Get a map of the graph parents of keys.
995
:param keys: The keys to look up parents for.
996
:return: A mapping from keys to parents. Absent keys are absent from
999
return self._get_parent_map_with_sources(keys)[0]
1001
def _get_parent_map_with_sources(self, keys):
1002
"""Get a map of the parents of keys.
1004
:param keys: The keys to look up parents for.
1005
:return: A tuple. The first element is a mapping from keys to parents.
1006
Absent keys are absent from the mapping. The second element is a
1007
list with the locations each key was found in. The first element
1008
is the in-this-knit parents, the second the first fallback source,
1012
sources = [self._index] + self._fallback_vfs
1015
for source in sources:
1018
new_result = source.get_parent_map(missing)
1019
source_results.append(new_result)
1020
result.update(new_result)
1021
missing.difference_update(set(new_result))
1022
return result, source_results
1024
def _get_block(self, index_memo):
1025
read_memo = index_memo[0:3]
1028
block = self._group_cache[read_memo]
1031
zdata = self._access.get_raw_records([read_memo]).next()
1032
# decompress - whole thing - this is not a bug, as it
1033
# permits caching. We might want to store the partially
1034
# decompresed group and decompress object, so that recent
1035
# texts are not penalised by big groups.
1036
block = GroupCompressBlock.from_bytes(zdata)
1037
self._group_cache[read_memo] = block
1039
# print len(zdata), len(plain)
1040
# parse - requires split_lines, better to have byte offsets
1041
# here (but not by much - we only split the region for the
1042
# recipe, and we often want to end up with lines anyway.
1045
def get_missing_compression_parent_keys(self):
1046
"""Return the keys of missing compression parents.
1048
Missing compression parents occur when a record stream was missing
1049
basis texts, or a index was scanned that had missing basis texts.
1051
# GroupCompress cannot currently reference texts that are not in the
1052
# group, so this is valid for now
1055
def get_record_stream(self, keys, ordering, include_delta_closure):
1056
"""Get a stream of records for keys.
1058
:param keys: The keys to include.
1059
:param ordering: Either 'unordered' or 'topological'. A topologically
1060
sorted stream has compression parents strictly before their
1062
:param include_delta_closure: If True then the closure across any
1063
compression parents will be included (in the opaque data).
1064
:return: An iterator of ContentFactory objects, each of which is only
1065
valid until the iterator is advanced.
1067
# keys might be a generator
1068
orig_keys = list(keys)
1072
if (not self._index.has_graph
1073
and ordering in ('topological', 'groupcompress')):
1074
# Cannot topological order when no graph has been stored.
1075
# but we allow 'as-requested' or 'unordered'
1076
ordering = 'unordered'
1078
remaining_keys = keys
1081
keys = set(remaining_keys)
1082
for content_factory in self._get_remaining_record_stream(keys,
1083
orig_keys, ordering, include_delta_closure):
1084
remaining_keys.discard(content_factory.key)
1085
yield content_factory
1087
except errors.RetryWithNewPacks, e:
1088
self._access.reload_or_raise(e)
1090
def _find_from_fallback(self, missing):
1091
"""Find whatever keys you can from the fallbacks.
1093
:param missing: A set of missing keys. This set will be mutated as keys
1094
are found from a fallback_vfs
1095
:return: (parent_map, key_to_source_map, source_results)
1096
parent_map the overall key => parent_keys
1097
key_to_source_map a dict from {key: source}
1098
source_results a list of (source: keys)
1101
key_to_source_map = {}
1103
for source in self._fallback_vfs:
1106
source_parents = source.get_parent_map(missing)
1107
parent_map.update(source_parents)
1108
source_parents = list(source_parents)
1109
source_results.append((source, source_parents))
1110
key_to_source_map.update((key, source) for key in source_parents)
1111
missing.difference_update(source_parents)
1112
return parent_map, key_to_source_map, source_results
1114
def _get_ordered_source_keys(self, ordering, parent_map, key_to_source_map):
1115
"""Get the (source, [keys]) list.
1117
The returned objects should be in the order defined by 'ordering',
1118
which can weave between different sources.
1119
:param ordering: Must be one of 'topological' or 'groupcompress'
1120
:return: List of [(source, [keys])] tuples, such that all keys are in
1121
the defined order, regardless of source.
1123
if ordering == 'topological':
1124
present_keys = topo_sort(parent_map)
1126
# ordering == 'groupcompress'
1127
# XXX: This only optimizes for the target ordering. We may need
1128
# to balance that with the time it takes to extract
1129
# ordering, by somehow grouping based on
1130
# locations[key][0:3]
1131
present_keys = sort_gc_optimal(parent_map)
1132
# Now group by source:
1134
current_source = None
1135
for key in present_keys:
1136
source = key_to_source_map.get(key, self)
1137
if source is not current_source:
1138
source_keys.append((source, []))
1139
current_source = source
1140
source_keys[-1][1].append(key)
1143
def _get_as_requested_source_keys(self, orig_keys, locations, unadded_keys,
1146
current_source = None
1147
for key in orig_keys:
1148
if key in locations or key in unadded_keys:
1150
elif key in key_to_source_map:
1151
source = key_to_source_map[key]
1154
if source is not current_source:
1155
source_keys.append((source, []))
1156
current_source = source
1157
source_keys[-1][1].append(key)
1160
def _get_io_ordered_source_keys(self, locations, unadded_keys,
1163
# This is the group the bytes are stored in, followed by the
1164
# location in the group
1165
return locations[key][0]
1166
present_keys = sorted(locations.iterkeys(), key=get_group)
1167
# We don't have an ordering for keys in the in-memory object, but
1168
# lets process the in-memory ones first.
1169
present_keys = list(unadded_keys) + present_keys
1170
# Now grab all of the ones from other sources
1171
source_keys = [(self, present_keys)]
1172
source_keys.extend(source_result)
1175
def _get_remaining_record_stream(self, keys, orig_keys, ordering,
1176
include_delta_closure):
1177
"""Get a stream of records for keys.
1179
:param keys: The keys to include.
1180
:param ordering: one of 'unordered', 'topological', 'groupcompress' or
1182
:param include_delta_closure: If True then the closure across any
1183
compression parents will be included (in the opaque data).
1184
:return: An iterator of ContentFactory objects, each of which is only
1185
valid until the iterator is advanced.
1188
locations = self._index.get_build_details(keys)
1189
unadded_keys = set(self._unadded_refs).intersection(keys)
1190
missing = keys.difference(locations)
1191
missing.difference_update(unadded_keys)
1192
(fallback_parent_map, key_to_source_map,
1193
source_result) = self._find_from_fallback(missing)
1194
if ordering in ('topological', 'groupcompress'):
1195
# would be better to not globally sort initially but instead
1196
# start with one key, recurse to its oldest parent, then grab
1197
# everything in the same group, etc.
1198
parent_map = dict((key, details[2]) for key, details in
1199
locations.iteritems())
1200
for key in unadded_keys:
1201
parent_map[key] = self._unadded_refs[key]
1202
parent_map.update(fallback_parent_map)
1203
source_keys = self._get_ordered_source_keys(ordering, parent_map,
1205
elif ordering == 'as-requested':
1206
source_keys = self._get_as_requested_source_keys(orig_keys,
1207
locations, unadded_keys, key_to_source_map)
1209
# We want to yield the keys in a semi-optimal (read-wise) ordering.
1210
# Otherwise we thrash the _group_cache and destroy performance
1211
source_keys = self._get_io_ordered_source_keys(locations,
1212
unadded_keys, source_result)
1214
yield AbsentContentFactory(key)
1216
last_read_memo = None
1217
# TODO: This works fairly well at batching up existing groups into a
1218
# streamable format, and possibly allowing for taking one big
1219
# group and splitting it when it isn't fully utilized.
1220
# However, it doesn't allow us to find under-utilized groups and
1221
# combine them into a bigger group on the fly.
1222
# (Consider the issue with how chk_map inserts texts
1223
# one-at-a-time.) This could be done at insert_record_stream()
1224
# time, but it probably would decrease the number of
1225
# bytes-on-the-wire for fetch.
1226
for source, keys in source_keys:
1229
if key in self._unadded_refs:
1230
if manager is not None:
1231
for factory in manager.get_record_stream():
1233
last_read_memo = manager = None
1234
bytes, sha1 = self._compressor.extract(key)
1235
parents = self._unadded_refs[key]
1236
yield FulltextContentFactory(key, parents, sha1, bytes)
1238
index_memo, _, parents, (method, _) = locations[key]
1239
read_memo = index_memo[0:3]
1240
if last_read_memo != read_memo:
1241
# We are starting a new block. If we have a
1242
# manager, we have found everything that fits for
1243
# now, so yield records
1244
if manager is not None:
1245
for factory in manager.get_record_stream():
1247
# Now start a new manager
1248
block = self._get_block(index_memo)
1249
manager = _LazyGroupContentManager(block)
1250
last_read_memo = read_memo
1251
start, end = index_memo[3:5]
1252
manager.add_factory(key, parents, start, end)
1254
if manager is not None:
1255
for factory in manager.get_record_stream():
1257
last_read_memo = manager = None
1258
for record in source.get_record_stream(keys, ordering,
1259
include_delta_closure):
1261
if manager is not None:
1262
for factory in manager.get_record_stream():
1265
def get_sha1s(self, keys):
1266
"""See VersionedFiles.get_sha1s()."""
1268
for record in self.get_record_stream(keys, 'unordered', True):
1269
if record.sha1 != None:
1270
result[record.key] = record.sha1
1272
if record.storage_kind != 'absent':
1273
result[record.key] = osutils.sha_string(
1274
record.get_bytes_as('fulltext'))
1277
def insert_record_stream(self, stream):
1278
"""Insert a record stream into this container.
1280
:param stream: A stream of records to insert.
1282
:seealso VersionedFiles.get_record_stream:
1284
# XXX: Setting random_id=True makes
1285
# test_insert_record_stream_existing_keys fail for groupcompress and
1286
# groupcompress-nograph, this needs to be revisited while addressing
1287
# 'bzr branch' performance issues.
1288
for _ in self._insert_record_stream(stream, random_id=False):
1291
def _insert_record_stream(self, stream, random_id=False, nostore_sha=None,
1293
"""Internal core to insert a record stream into this container.
1295
This helper function has a different interface than insert_record_stream
1296
to allow add_lines to be minimal, but still return the needed data.
1298
:param stream: A stream of records to insert.
1299
:param nostore_sha: If the sha1 of a given text matches nostore_sha,
1300
raise ExistingContent, rather than committing the new text.
1301
:param reuse_blocks: If the source is streaming from
1302
groupcompress-blocks, just insert the blocks as-is, rather than
1303
expanding the texts and inserting again.
1304
:return: An iterator over the sha1 of the inserted records.
1305
:seealso insert_record_stream:
1309
def get_adapter(adapter_key):
1311
return adapters[adapter_key]
1313
adapter_factory = adapter_registry.get(adapter_key)
1314
adapter = adapter_factory(self)
1315
adapters[adapter_key] = adapter
1317
# This will go up to fulltexts for gc to gc fetching, which isn't
1319
self._compressor = GroupCompressor()
1320
self._unadded_refs = {}
1323
bytes = self._compressor.flush().to_bytes()
1324
index, start, length = self._access.add_raw_records(
1325
[(None, len(bytes))], bytes)[0]
1327
for key, reads, refs in keys_to_add:
1328
nodes.append((key, "%d %d %s" % (start, length, reads), refs))
1329
self._index.add_records(nodes, random_id=random_id)
1330
self._unadded_refs = {}
1332
self._compressor = GroupCompressor()
1335
max_fulltext_len = 0
1336
max_fulltext_prefix = None
1337
insert_manager = None
1340
# XXX: TODO: remove this, it is just for safety checking for now
1341
inserted_keys = set()
1342
for record in stream:
1343
# Raise an error when a record is missing.
1344
if record.storage_kind == 'absent':
1345
raise errors.RevisionNotPresent(record.key, self)
1347
if record.key in inserted_keys:
1348
trace.note('Insert claimed random_id=True,'
1349
' but then inserted %r two times', record.key)
1351
inserted_keys.add(record.key)
1353
# If the reuse_blocks flag is set, check to see if we can just
1354
# copy a groupcompress block as-is.
1355
if record.storage_kind == 'groupcompress-block':
1356
# Insert the raw block into the target repo
1357
insert_manager = record._manager
1358
insert_manager._check_rebuild_block()
1359
bytes = record._manager._block.to_bytes()
1360
_, start, length = self._access.add_raw_records(
1361
[(None, len(bytes))], bytes)[0]
1364
block_length = length
1365
if record.storage_kind in ('groupcompress-block',
1366
'groupcompress-block-ref'):
1367
if insert_manager is None:
1368
raise AssertionError('No insert_manager set')
1369
value = "%d %d %d %d" % (block_start, block_length,
1370
record._start, record._end)
1371
nodes = [(record.key, value, (record.parents,))]
1372
# TODO: Consider buffering up many nodes to be added, not
1373
# sure how much overhead this has, but we're seeing
1374
# ~23s / 120s in add_records calls
1375
self._index.add_records(nodes, random_id=random_id)
1378
bytes = record.get_bytes_as('fulltext')
1379
except errors.UnavailableRepresentation:
1380
adapter_key = record.storage_kind, 'fulltext'
1381
adapter = get_adapter(adapter_key)
1382
bytes = adapter.get_bytes(record)
1383
if len(record.key) > 1:
1384
prefix = record.key[0]
1385
soft = (prefix == last_prefix)
1389
if max_fulltext_len < len(bytes):
1390
max_fulltext_len = len(bytes)
1391
max_fulltext_prefix = prefix
1392
(found_sha1, start_point, end_point,
1393
type) = self._compressor.compress(record.key,
1394
bytes, record.sha1, soft=soft,
1395
nostore_sha=nostore_sha)
1396
# delta_ratio = float(len(bytes)) / (end_point - start_point)
1397
# Check if we want to continue to include that text
1398
if (prefix == max_fulltext_prefix
1399
and end_point < 2 * max_fulltext_len):
1400
# As long as we are on the same file_id, we will fill at least
1401
# 2 * max_fulltext_len
1402
start_new_block = False
1403
elif end_point > 4*1024*1024:
1404
start_new_block = True
1405
elif (prefix is not None and prefix != last_prefix
1406
and end_point > 2*1024*1024):
1407
start_new_block = True
1409
start_new_block = False
1410
last_prefix = prefix
1412
self._compressor.pop_last()
1414
max_fulltext_len = len(bytes)
1415
(found_sha1, start_point, end_point,
1416
type) = self._compressor.compress(record.key, bytes,
1418
if record.key[-1] is None:
1419
key = record.key[:-1] + ('sha1:' + found_sha1,)
1422
self._unadded_refs[key] = record.parents
1424
keys_to_add.append((key, '%d %d' % (start_point, end_point),
1426
if len(keys_to_add):
1428
self._compressor = None
1430
def iter_lines_added_or_present_in_keys(self, keys, pb=None):
1431
"""Iterate over the lines in the versioned files from keys.
1433
This may return lines from other keys. Each item the returned
1434
iterator yields is a tuple of a line and a text version that that line
1435
is present in (not introduced in).
1437
Ordering of results is in whatever order is most suitable for the
1438
underlying storage format.
1440
If a progress bar is supplied, it may be used to indicate progress.
1441
The caller is responsible for cleaning up progress bars (because this
1445
* Lines are normalised by the underlying store: they will all have \n
1447
* Lines are returned in arbitrary order.
1449
:return: An iterator over (line, key).
1452
pb = progress.DummyProgress()
1455
# we don't care about inclusions, the caller cares.
1456
# but we need to setup a list of records to visit.
1457
# we need key, position, length
1458
for key_idx, record in enumerate(self.get_record_stream(keys,
1459
'unordered', True)):
1460
# XXX: todo - optimise to use less than full texts.
1462
pb.update('Walking content', key_idx, total)
1463
if record.storage_kind == 'absent':
1464
raise errors.RevisionNotPresent(key, self)
1465
lines = osutils.split_lines(record.get_bytes_as('fulltext'))
1468
pb.update('Walking content', total, total)
1471
"""See VersionedFiles.keys."""
1472
if 'evil' in debug.debug_flags:
1473
trace.mutter_callsite(2, "keys scales with size of history")
1474
sources = [self._index] + self._fallback_vfs
1476
for source in sources:
1477
result.update(source.keys())
1481
class _GCGraphIndex(object):
1482
"""Mapper from GroupCompressVersionedFiles needs into GraphIndex storage."""
1484
def __init__(self, graph_index, is_locked, parents=True,
1486
"""Construct a _GCGraphIndex on a graph_index.
1488
:param graph_index: An implementation of bzrlib.index.GraphIndex.
1489
:param is_locked: A callback, returns True if the index is locked and
1491
:param parents: If True, record knits parents, if not do not record
1493
:param add_callback: If not None, allow additions to the index and call
1494
this callback with a list of added GraphIndex nodes:
1495
[(node, value, node_refs), ...]
1497
self._add_callback = add_callback
1498
self._graph_index = graph_index
1499
self._parents = parents
1500
self.has_graph = parents
1501
self._is_locked = is_locked
1503
def add_records(self, records, random_id=False):
1504
"""Add multiple records to the index.
1506
This function does not insert data into the Immutable GraphIndex
1507
backing the KnitGraphIndex, instead it prepares data for insertion by
1508
the caller and checks that it is safe to insert then calls
1509
self._add_callback with the prepared GraphIndex nodes.
1511
:param records: a list of tuples:
1512
(key, options, access_memo, parents).
1513
:param random_id: If True the ids being added were randomly generated
1514
and no check for existence will be performed.
1516
if not self._add_callback:
1517
raise errors.ReadOnlyError(self)
1518
# we hope there are no repositories with inconsistent parentage
1523
for (key, value, refs) in records:
1524
if not self._parents:
1528
raise KnitCorrupt(self,
1529
"attempt to add node with parents "
1530
"in parentless index.")
1533
keys[key] = (value, refs)
1536
present_nodes = self._get_entries(keys)
1537
for (index, key, value, node_refs) in present_nodes:
1538
if node_refs != keys[key][1]:
1539
raise errors.KnitCorrupt(self, "inconsistent details in add_records"
1540
": %s %s" % ((value, node_refs), keys[key]))
1546
for key, (value, node_refs) in keys.iteritems():
1547
result.append((key, value, node_refs))
1549
for key, (value, node_refs) in keys.iteritems():
1550
result.append((key, value))
1552
self._add_callback(records)
1554
def _check_read(self):
1555
"""Raise an exception if reads are not permitted."""
1556
if not self._is_locked():
1557
raise errors.ObjectNotLocked(self)
1559
def _check_write_ok(self):
1560
"""Raise an exception if writes are not permitted."""
1561
if not self._is_locked():
1562
raise errors.ObjectNotLocked(self)
1564
def _get_entries(self, keys, check_present=False):
1565
"""Get the entries for keys.
1567
Note: Callers are responsible for checking that the index is locked
1568
before calling this method.
1570
:param keys: An iterable of index key tuples.
1575
for node in self._graph_index.iter_entries(keys):
1577
found_keys.add(node[1])
1579
# adapt parentless index to the rest of the code.
1580
for node in self._graph_index.iter_entries(keys):
1581
yield node[0], node[1], node[2], ()
1582
found_keys.add(node[1])
1584
missing_keys = keys.difference(found_keys)
1586
raise RevisionNotPresent(missing_keys.pop(), self)
1588
def get_parent_map(self, keys):
1589
"""Get a map of the parents of keys.
1591
:param keys: The keys to look up parents for.
1592
:return: A mapping from keys to parents. Absent keys are absent from
1596
nodes = self._get_entries(keys)
1600
result[node[1]] = node[3][0]
1603
result[node[1]] = None
1606
def get_build_details(self, keys):
1607
"""Get the various build details for keys.
1609
Ghosts are omitted from the result.
1611
:param keys: An iterable of keys.
1612
:return: A dict of key:
1613
(index_memo, compression_parent, parents, record_details).
1615
opaque structure to pass to read_records to extract the raw
1618
Content that this record is built upon, may be None
1620
Logical parents of this node
1622
extra information about the content which needs to be passed to
1623
Factory.parse_record
1627
entries = self._get_entries(keys)
1628
for entry in entries:
1630
if not self._parents:
1633
parents = entry[3][0]
1635
result[key] = (self._node_to_position(entry),
1636
None, parents, (method, None))
1640
"""Get all the keys in the collection.
1642
The keys are not ordered.
1645
return [node[1] for node in self._graph_index.iter_all_entries()]
1647
def _node_to_position(self, node):
1648
"""Convert an index value to position details."""
1649
bits = node[2].split(' ')
1650
# It would be nice not to read the entire gzip.
1651
start = int(bits[0])
1653
basis_end = int(bits[2])
1654
delta_end = int(bits[3])
1655
return node[0], start, stop, basis_end, delta_end
1658
from bzrlib._groupcompress_py import (
1660
apply_delta_to_source,
1666
from bzrlib._groupcompress_pyx import (
1668
apply_delta_to_source,
1673
GroupCompressor = PyrexGroupCompressor
1675
GroupCompressor = PythonGroupCompressor
added
removed
bzrlib/groupcompress.py
