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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.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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self._content_chunks = 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._content_chunks is not None:
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self._content = ''.join(self._content_chunks)
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self._content_chunks = None
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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_chunked_content(self, content_chunks, length):
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"""Set the content of this block to the given chunks."""
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# If we have lots of short lines, it is may be more efficient to join
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# the content ahead of time. If the content is <10MiB, we don't really
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# care about the extra memory consumption, so we can just pack it and
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# be done. However, timing showed 18s => 17.9s for repacking 1k revs of
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# mysql, which is below the noise margin
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self._content_length = length
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self._content_chunks = content_chunks
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self._z_content = None
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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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def _create_z_content_using_lzma(self):
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if self._content_chunks is not None:
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self._content = ''.join(self._content_chunks)
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self._content_chunks = 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 = pylzma.compress(self._content)
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self._z_content_length = len(self._z_content)
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def _create_z_content_from_chunks(self):
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compressor = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION)
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compressed_chunks = map(compressor.compress, self._content_chunks)
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compressed_chunks.append(compressor.flush())
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self._z_content = ''.join(compressed_chunks)
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self._z_content_length = len(self._z_content)
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def _create_z_content(self):
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if self._z_content is not None:
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self._create_z_content_using_lzma()
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if self._content_chunks is not None:
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self._create_z_content_from_chunks()
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self._z_content = zlib.compress(self._content)
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self._z_content_length = len(self._z_content)
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"""Encode the information into a byte stream."""
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self._create_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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def _dump(self, include_text=False):
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"""Take this block, and spit out a human-readable structure.
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:param include_text: Inserts also include text bits, chose whether you
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want this displayed in the dump or not.
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:return: A dump of the given block. The layout is something like:
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[('f', length), ('d', delta_length, text_length, [delta_info])]
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delta_info := [('i', num_bytes, text), ('c', offset, num_bytes),
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self._ensure_content()
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while pos < self._content_length:
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kind = self._content[pos]
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if kind not in ('f', 'd'):
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raise ValueError('invalid kind character: %r' % (kind,))
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content_len, len_len = decode_base128_int(
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self._content[pos:pos + 5])
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if content_len + pos > self._content_length:
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raise ValueError('invalid content_len %d for record @ pos %d'
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% (content_len, pos - len_len - 1))
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if kind == 'f': # Fulltext
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text = self._content[pos:pos+content_len]
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result.append(('f', content_len, text))
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result.append(('f', content_len))
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elif kind == 'd': # Delta
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delta_content = self._content[pos:pos+content_len]
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# The first entry in a delta is the decompressed length
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decomp_len, delta_pos = decode_base128_int(delta_content)
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result.append(('d', content_len, decomp_len, delta_info))
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while delta_pos < content_len:
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c = ord(delta_content[delta_pos])
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delta_pos) = decode_copy_instruction(delta_content, c,
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text = self._content[offset:offset+length]
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delta_info.append(('c', offset, length, text))
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delta_info.append(('c', offset, length))
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measured_len += length
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txt = delta_content[delta_pos:delta_pos+c]
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delta_info.append(('i', c, txt))
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if delta_pos != content_len:
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raise ValueError('Delta consumed a bad number of bytes:'
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' %d != %d' % (delta_pos, content_len))
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if measured_len != decomp_len:
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raise ValueError('Delta claimed fulltext was %d bytes, but'
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' extraction resulted in %d bytes'
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% (decomp_len, measured_len))
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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,))
683
manager = _LazyGroupContentManager.from_bytes(bytes)
684
return manager.get_record_stream()
687
class _CommonGroupCompressor(object):
690
"""Create a GroupCompressor."""
695
self.labels_deltas = {}
696
self._delta_index = None # Set by the children
697
self._block = GroupCompressBlock()
699
def compress(self, key, bytes, expected_sha, nostore_sha=None, soft=False):
700
"""Compress lines with label key.
702
:param key: A key tuple. It is stored in the output
703
for identification of the text during decompression. If the last
704
element is 'None' it is replaced with the sha1 of the text -
706
:param bytes: The bytes to be compressed
707
:param expected_sha: If non-None, the sha the lines are believed to
708
have. During compression the sha is calculated; a mismatch will
710
:param nostore_sha: If the computed sha1 sum matches, we will raise
711
ExistingContent rather than adding the text.
712
:param soft: Do a 'soft' compression. This means that we require larger
713
ranges to match to be considered for a copy command.
715
:return: The sha1 of lines, the start and end offsets in the delta, and
716
the type ('fulltext' or 'delta').
718
:seealso VersionedFiles.add_lines:
720
if not bytes: # empty, like a dir entry, etc
721
if nostore_sha == _null_sha1:
722
raise errors.ExistingContent()
723
return _null_sha1, 0, 0, 'fulltext'
724
# we assume someone knew what they were doing when they passed it in
725
if expected_sha is not None:
728
sha1 = osutils.sha_string(bytes)
729
if nostore_sha is not None:
730
if sha1 == nostore_sha:
731
raise errors.ExistingContent()
733
key = key[:-1] + ('sha1:' + sha1,)
735
start, end, type = self._compress(key, bytes, len(bytes) / 2, soft)
736
return sha1, start, end, type
738
def _compress(self, key, bytes, max_delta_size, soft=False):
739
"""Compress lines with label key.
741
:param key: A key tuple. It is stored in the output for identification
742
of the text during decompression.
744
:param bytes: The bytes to be compressed
746
:param max_delta_size: The size above which we issue a fulltext instead
749
:param soft: Do a 'soft' compression. This means that we require larger
750
ranges to match to be considered for a copy command.
752
:return: The sha1 of lines, the start and end offsets in the delta, and
753
the type ('fulltext' or 'delta').
755
raise NotImplementedError(self._compress)
757
def extract(self, key):
758
"""Extract a key previously added to the compressor.
760
:param key: The key to extract.
761
:return: An iterable over bytes and the sha1.
763
(start_byte, start_chunk, end_byte, end_chunk) = self.labels_deltas[key]
764
delta_chunks = self.chunks[start_chunk:end_chunk]
765
stored_bytes = ''.join(delta_chunks)
766
if stored_bytes[0] == 'f':
767
fulltext_len, offset = decode_base128_int(stored_bytes[1:10])
768
data_len = fulltext_len + 1 + offset
769
if data_len != len(stored_bytes):
770
raise ValueError('Index claimed fulltext len, but stored bytes'
772
% (len(stored_bytes), data_len))
773
bytes = stored_bytes[offset + 1:]
775
# XXX: This is inefficient at best
776
source = ''.join(self.chunks[:start_chunk])
777
if stored_bytes[0] != 'd':
778
raise ValueError('Unknown content kind, bytes claim %s'
779
% (stored_bytes[0],))
780
delta_len, offset = decode_base128_int(stored_bytes[1:10])
781
data_len = delta_len + 1 + offset
782
if data_len != len(stored_bytes):
783
raise ValueError('Index claimed delta len, but stored bytes'
785
% (len(stored_bytes), data_len))
786
bytes = apply_delta(source, stored_bytes[offset + 1:])
787
bytes_sha1 = osutils.sha_string(bytes)
788
return bytes, bytes_sha1
791
"""Finish this group, creating a formatted stream.
793
After calling this, the compressor should no longer be used
795
# TODO: this causes us to 'bloat' to 2x the size of content in the
796
# group. This has an impact for 'commit' of large objects.
797
# One possibility is to use self._content_chunks, and be lazy and
798
# only fill out self._content as a full string when we actually
799
# need it. That would at least drop the peak memory consumption
800
# for 'commit' down to ~1x the size of the largest file, at a
801
# cost of increased complexity within this code. 2x is still <<
802
# 3x the size of the largest file, so we are doing ok.
803
self._block.set_chunked_content(self.chunks, self.endpoint)
805
self._delta_index = None
809
"""Call this if you want to 'revoke' the last compression.
811
After this, the data structures will be rolled back, but you cannot do
814
self._delta_index = None
815
del self.chunks[self._last[0]:]
816
self.endpoint = self._last[1]
820
"""Return the overall compression ratio."""
821
return float(self.input_bytes) / float(self.endpoint)
824
class PythonGroupCompressor(_CommonGroupCompressor):
827
"""Create a GroupCompressor.
829
Used only if the pyrex version is not available.
831
super(PythonGroupCompressor, self).__init__()
832
self._delta_index = LinesDeltaIndex([])
833
# The actual content is managed by LinesDeltaIndex
834
self.chunks = self._delta_index.lines
836
def _compress(self, key, bytes, max_delta_size, soft=False):
837
"""see _CommonGroupCompressor._compress"""
838
input_len = len(bytes)
839
new_lines = osutils.split_lines(bytes)
840
out_lines, index_lines = self._delta_index.make_delta(
841
new_lines, bytes_length=input_len, soft=soft)
842
delta_length = sum(map(len, out_lines))
843
if delta_length > max_delta_size:
844
# The delta is longer than the fulltext, insert a fulltext
846
out_lines = ['f', encode_base128_int(input_len)]
847
out_lines.extend(new_lines)
848
index_lines = [False, False]
849
index_lines.extend([True] * len(new_lines))
851
# this is a worthy delta, output it
854
# Update the delta_length to include those two encoded integers
855
out_lines[1] = encode_base128_int(delta_length)
857
start = self.endpoint
858
chunk_start = len(self.chunks)
859
self._last = (chunk_start, self.endpoint)
860
self._delta_index.extend_lines(out_lines, index_lines)
861
self.endpoint = self._delta_index.endpoint
862
self.input_bytes += input_len
863
chunk_end = len(self.chunks)
864
self.labels_deltas[key] = (start, chunk_start,
865
self.endpoint, chunk_end)
866
return start, self.endpoint, type
869
class PyrexGroupCompressor(_CommonGroupCompressor):
870
"""Produce a serialised group of compressed texts.
872
It contains code very similar to SequenceMatcher because of having a similar
873
task. However some key differences apply:
874
- there is no junk, we want a minimal edit not a human readable diff.
875
- we don't filter very common lines (because we don't know where a good
876
range will start, and after the first text we want to be emitting minmal
878
- we chain the left side, not the right side
879
- we incrementally update the adjacency matrix as new lines are provided.
880
- we look for matches in all of the left side, so the routine which does
881
the analagous task of find_longest_match does not need to filter on the
886
super(PyrexGroupCompressor, self).__init__()
887
self._delta_index = DeltaIndex()
889
def _compress(self, key, bytes, max_delta_size, soft=False):
890
"""see _CommonGroupCompressor._compress"""
891
input_len = len(bytes)
892
# By having action/label/sha1/len, we can parse the group if the index
893
# was ever destroyed, we have the key in 'label', we know the final
894
# bytes are valid from sha1, and we know where to find the end of this
895
# record because of 'len'. (the delta record itself will store the
896
# total length for the expanded record)
897
# 'len: %d\n' costs approximately 1% increase in total data
898
# Having the labels at all costs us 9-10% increase, 38% increase for
899
# inventory pages, and 5.8% increase for text pages
900
# new_chunks = ['label:%s\nsha1:%s\n' % (label, sha1)]
901
if self._delta_index._source_offset != self.endpoint:
902
raise AssertionError('_source_offset != endpoint'
903
' somehow the DeltaIndex got out of sync with'
905
delta = self._delta_index.make_delta(bytes, max_delta_size)
908
enc_length = encode_base128_int(len(bytes))
909
len_mini_header = 1 + len(enc_length)
910
self._delta_index.add_source(bytes, len_mini_header)
911
new_chunks = ['f', enc_length, bytes]
914
enc_length = encode_base128_int(len(delta))
915
len_mini_header = 1 + len(enc_length)
916
new_chunks = ['d', enc_length, delta]
917
self._delta_index.add_delta_source(delta, len_mini_header)
919
start = self.endpoint
920
chunk_start = len(self.chunks)
921
# Now output these bytes
922
self._output_chunks(new_chunks)
923
self.input_bytes += input_len
924
chunk_end = len(self.chunks)
925
self.labels_deltas[key] = (start, chunk_start,
926
self.endpoint, chunk_end)
927
if not self._delta_index._source_offset == self.endpoint:
928
raise AssertionError('the delta index is out of sync'
929
'with the output lines %s != %s'
930
% (self._delta_index._source_offset, self.endpoint))
931
return start, self.endpoint, type
933
def _output_chunks(self, new_chunks):
934
"""Output some chunks.
936
:param new_chunks: The chunks to output.
938
self._last = (len(self.chunks), self.endpoint)
939
endpoint = self.endpoint
940
self.chunks.extend(new_chunks)
941
endpoint += sum(map(len, new_chunks))
942
self.endpoint = endpoint
945
def make_pack_factory(graph, delta, keylength):
946
"""Create a factory for creating a pack based groupcompress.
948
This is only functional enough to run interface tests, it doesn't try to
949
provide a full pack environment.
951
:param graph: Store a graph.
952
:param delta: Delta compress contents.
953
:param keylength: How long should keys be.
955
def factory(transport):
960
graph_index = BTreeBuilder(reference_lists=ref_length,
961
key_elements=keylength)
962
stream = transport.open_write_stream('newpack')
963
writer = pack.ContainerWriter(stream.write)
965
index = _GCGraphIndex(graph_index, lambda:True, parents=parents,
966
add_callback=graph_index.add_nodes)
967
access = knit._DirectPackAccess({})
968
access.set_writer(writer, graph_index, (transport, 'newpack'))
969
result = GroupCompressVersionedFiles(index, access, delta)
970
result.stream = stream
971
result.writer = writer
976
def cleanup_pack_group(versioned_files):
977
versioned_files.writer.end()
978
versioned_files.stream.close()
981
class GroupCompressVersionedFiles(VersionedFiles):
982
"""A group-compress based VersionedFiles implementation."""
984
def __init__(self, index, access, delta=True):
985
"""Create a GroupCompressVersionedFiles object.
987
:param index: The index object storing access and graph data.
988
:param access: The access object storing raw data.
989
:param delta: Whether to delta compress or just entropy compress.
992
self._access = access
994
self._unadded_refs = {}
995
self._group_cache = LRUSizeCache(max_size=50*1024*1024)
996
self._fallback_vfs = []
998
def add_lines(self, key, parents, lines, parent_texts=None,
999
left_matching_blocks=None, nostore_sha=None, random_id=False,
1000
check_content=True):
1001
"""Add a text to the store.
1003
:param key: The key tuple of the text to add.
1004
:param parents: The parents key tuples of the text to add.
1005
:param lines: A list of lines. Each line must be a bytestring. And all
1006
of them except the last must be terminated with \n and contain no
1007
other \n's. The last line may either contain no \n's or a single
1008
terminating \n. If the lines list does meet this constraint the add
1009
routine may error or may succeed - but you will be unable to read
1010
the data back accurately. (Checking the lines have been split
1011
correctly is expensive and extremely unlikely to catch bugs so it
1012
is not done at runtime unless check_content is True.)
1013
:param parent_texts: An optional dictionary containing the opaque
1014
representations of some or all of the parents of version_id to
1015
allow delta optimisations. VERY IMPORTANT: the texts must be those
1016
returned by add_lines or data corruption can be caused.
1017
:param left_matching_blocks: a hint about which areas are common
1018
between the text and its left-hand-parent. The format is
1019
the SequenceMatcher.get_matching_blocks format.
1020
:param nostore_sha: Raise ExistingContent and do not add the lines to
1021
the versioned file if the digest of the lines matches this.
1022
:param random_id: If True a random id has been selected rather than
1023
an id determined by some deterministic process such as a converter
1024
from a foreign VCS. When True the backend may choose not to check
1025
for uniqueness of the resulting key within the versioned file, so
1026
this should only be done when the result is expected to be unique
1028
:param check_content: If True, the lines supplied are verified to be
1029
bytestrings that are correctly formed lines.
1030
:return: The text sha1, the number of bytes in the text, and an opaque
1031
representation of the inserted version which can be provided
1032
back to future add_lines calls in the parent_texts dictionary.
1034
self._index._check_write_ok()
1035
self._check_add(key, lines, random_id, check_content)
1037
# The caller might pass None if there is no graph data, but kndx
1038
# indexes can't directly store that, so we give them
1039
# an empty tuple instead.
1041
# double handling for now. Make it work until then.
1042
length = sum(map(len, lines))
1043
record = ChunkedContentFactory(key, parents, None, lines)
1044
sha1 = list(self._insert_record_stream([record], random_id=random_id,
1045
nostore_sha=nostore_sha))[0]
1046
return sha1, length, None
1048
def _add_text(self, key, parents, text, nostore_sha=None, random_id=False):
1049
"""See VersionedFiles._add_text()."""
1050
self._index._check_write_ok()
1051
self._check_add(key, None, random_id, check_content=False)
1052
if text.__class__ is not str:
1053
raise errors.BzrBadParameterUnicode("text")
1055
# The caller might pass None if there is no graph data, but kndx
1056
# indexes can't directly store that, so we give them
1057
# an empty tuple instead.
1059
# double handling for now. Make it work until then.
1061
record = FulltextContentFactory(key, parents, None, text)
1062
sha1 = list(self._insert_record_stream([record], random_id=random_id,
1063
nostore_sha=nostore_sha))[0]
1064
return sha1, length, None
1066
def add_fallback_versioned_files(self, a_versioned_files):
1067
"""Add a source of texts for texts not present in this knit.
1069
:param a_versioned_files: A VersionedFiles object.
1071
self._fallback_vfs.append(a_versioned_files)
1073
def annotate(self, key):
1074
"""See VersionedFiles.annotate."""
1076
parent_map = self.get_parent_map([key])
1078
raise errors.RevisionNotPresent(key, self)
1079
if parent_map[key] is not None:
1080
parent_map = dict((k, v) for k, v in graph.iter_ancestry([key])
1082
keys = parent_map.keys()
1085
parent_map = {key:()}
1086
# We used Graph(self) to load the parent_map, but now that we have it,
1087
# we can just query the parent map directly, so create a KnownGraph
1088
heads_provider = _mod_graph.KnownGraph(parent_map)
1090
reannotate = annotate.reannotate
1091
for record in self.get_record_stream(keys, 'topological', True):
1093
lines = osutils.chunks_to_lines(record.get_bytes_as('chunked'))
1094
parent_lines = [parent_cache[parent] for parent in parent_map[key]]
1095
parent_cache[key] = list(
1096
reannotate(parent_lines, lines, key, None, heads_provider))
1097
return parent_cache[key]
1099
def check(self, progress_bar=None):
1100
"""See VersionedFiles.check()."""
1102
for record in self.get_record_stream(keys, 'unordered', True):
1103
record.get_bytes_as('fulltext')
1105
def _check_add(self, key, lines, random_id, check_content):
1106
"""check that version_id and lines are safe to add."""
1107
version_id = key[-1]
1108
if version_id is not None:
1109
if osutils.contains_whitespace(version_id):
1110
raise errors.InvalidRevisionId(version_id, self)
1111
self.check_not_reserved_id(version_id)
1112
# TODO: If random_id==False and the key is already present, we should
1113
# probably check that the existing content is identical to what is
1114
# being inserted, and otherwise raise an exception. This would make
1115
# the bundle code simpler.
1117
self._check_lines_not_unicode(lines)
1118
self._check_lines_are_lines(lines)
1120
def get_parent_map(self, keys):
1121
"""Get a map of the graph parents of keys.
1123
:param keys: The keys to look up parents for.
1124
:return: A mapping from keys to parents. Absent keys are absent from
1127
return self._get_parent_map_with_sources(keys)[0]
1129
def _get_parent_map_with_sources(self, keys):
1130
"""Get a map of the parents of keys.
1132
:param keys: The keys to look up parents for.
1133
:return: A tuple. The first element is a mapping from keys to parents.
1134
Absent keys are absent from the mapping. The second element is a
1135
list with the locations each key was found in. The first element
1136
is the in-this-knit parents, the second the first fallback source,
1140
sources = [self._index] + self._fallback_vfs
1143
for source in sources:
1146
new_result = source.get_parent_map(missing)
1147
source_results.append(new_result)
1148
result.update(new_result)
1149
missing.difference_update(set(new_result))
1150
return result, source_results
1152
def _get_block(self, index_memo):
1153
read_memo = index_memo[0:3]
1156
block = self._group_cache[read_memo]
1159
zdata = self._access.get_raw_records([read_memo]).next()
1160
# decompress - whole thing - this is not a bug, as it
1161
# permits caching. We might want to store the partially
1162
# decompresed group and decompress object, so that recent
1163
# texts are not penalised by big groups.
1164
block = GroupCompressBlock.from_bytes(zdata)
1165
self._group_cache[read_memo] = block
1167
# print len(zdata), len(plain)
1168
# parse - requires split_lines, better to have byte offsets
1169
# here (but not by much - we only split the region for the
1170
# recipe, and we often want to end up with lines anyway.
1173
def get_missing_compression_parent_keys(self):
1174
"""Return the keys of missing compression parents.
1176
Missing compression parents occur when a record stream was missing
1177
basis texts, or a index was scanned that had missing basis texts.
1179
# GroupCompress cannot currently reference texts that are not in the
1180
# group, so this is valid for now
1183
def get_record_stream(self, keys, ordering, include_delta_closure):
1184
"""Get a stream of records for keys.
1186
:param keys: The keys to include.
1187
:param ordering: Either 'unordered' or 'topological'. A topologically
1188
sorted stream has compression parents strictly before their
1190
:param include_delta_closure: If True then the closure across any
1191
compression parents will be included (in the opaque data).
1192
:return: An iterator of ContentFactory objects, each of which is only
1193
valid until the iterator is advanced.
1195
# keys might be a generator
1196
orig_keys = list(keys)
1200
if (not self._index.has_graph
1201
and ordering in ('topological', 'groupcompress')):
1202
# Cannot topological order when no graph has been stored.
1203
# but we allow 'as-requested' or 'unordered'
1204
ordering = 'unordered'
1206
remaining_keys = keys
1209
keys = set(remaining_keys)
1210
for content_factory in self._get_remaining_record_stream(keys,
1211
orig_keys, ordering, include_delta_closure):
1212
remaining_keys.discard(content_factory.key)
1213
yield content_factory
1215
except errors.RetryWithNewPacks, e:
1216
self._access.reload_or_raise(e)
1218
def _find_from_fallback(self, missing):
1219
"""Find whatever keys you can from the fallbacks.
1221
:param missing: A set of missing keys. This set will be mutated as keys
1222
are found from a fallback_vfs
1223
:return: (parent_map, key_to_source_map, source_results)
1224
parent_map the overall key => parent_keys
1225
key_to_source_map a dict from {key: source}
1226
source_results a list of (source: keys)
1229
key_to_source_map = {}
1231
for source in self._fallback_vfs:
1234
source_parents = source.get_parent_map(missing)
1235
parent_map.update(source_parents)
1236
source_parents = list(source_parents)
1237
source_results.append((source, source_parents))
1238
key_to_source_map.update((key, source) for key in source_parents)
1239
missing.difference_update(source_parents)
1240
return parent_map, key_to_source_map, source_results
1242
def _get_ordered_source_keys(self, ordering, parent_map, key_to_source_map):
1243
"""Get the (source, [keys]) list.
1245
The returned objects should be in the order defined by 'ordering',
1246
which can weave between different sources.
1247
:param ordering: Must be one of 'topological' or 'groupcompress'
1248
:return: List of [(source, [keys])] tuples, such that all keys are in
1249
the defined order, regardless of source.
1251
if ordering == 'topological':
1252
present_keys = topo_sort(parent_map)
1254
# ordering == 'groupcompress'
1255
# XXX: This only optimizes for the target ordering. We may need
1256
# to balance that with the time it takes to extract
1257
# ordering, by somehow grouping based on
1258
# locations[key][0:3]
1259
present_keys = sort_gc_optimal(parent_map)
1260
# Now group by source:
1262
current_source = None
1263
for key in present_keys:
1264
source = key_to_source_map.get(key, self)
1265
if source is not current_source:
1266
source_keys.append((source, []))
1267
current_source = source
1268
source_keys[-1][1].append(key)
1271
def _get_as_requested_source_keys(self, orig_keys, locations, unadded_keys,
1274
current_source = None
1275
for key in orig_keys:
1276
if key in locations or key in unadded_keys:
1278
elif key in key_to_source_map:
1279
source = key_to_source_map[key]
1282
if source is not current_source:
1283
source_keys.append((source, []))
1284
current_source = source
1285
source_keys[-1][1].append(key)
1288
def _get_io_ordered_source_keys(self, locations, unadded_keys,
1291
# This is the group the bytes are stored in, followed by the
1292
# location in the group
1293
return locations[key][0]
1294
present_keys = sorted(locations.iterkeys(), key=get_group)
1295
# We don't have an ordering for keys in the in-memory object, but
1296
# lets process the in-memory ones first.
1297
present_keys = list(unadded_keys) + present_keys
1298
# Now grab all of the ones from other sources
1299
source_keys = [(self, present_keys)]
1300
source_keys.extend(source_result)
1303
def _get_remaining_record_stream(self, keys, orig_keys, ordering,
1304
include_delta_closure):
1305
"""Get a stream of records for keys.
1307
:param keys: The keys to include.
1308
:param ordering: one of 'unordered', 'topological', 'groupcompress' or
1310
:param include_delta_closure: If True then the closure across any
1311
compression parents will be included (in the opaque data).
1312
:return: An iterator of ContentFactory objects, each of which is only
1313
valid until the iterator is advanced.
1316
locations = self._index.get_build_details(keys)
1317
unadded_keys = set(self._unadded_refs).intersection(keys)
1318
missing = keys.difference(locations)
1319
missing.difference_update(unadded_keys)
1320
(fallback_parent_map, key_to_source_map,
1321
source_result) = self._find_from_fallback(missing)
1322
if ordering in ('topological', 'groupcompress'):
1323
# would be better to not globally sort initially but instead
1324
# start with one key, recurse to its oldest parent, then grab
1325
# everything in the same group, etc.
1326
parent_map = dict((key, details[2]) for key, details in
1327
locations.iteritems())
1328
for key in unadded_keys:
1329
parent_map[key] = self._unadded_refs[key]
1330
parent_map.update(fallback_parent_map)
1331
source_keys = self._get_ordered_source_keys(ordering, parent_map,
1333
elif ordering == 'as-requested':
1334
source_keys = self._get_as_requested_source_keys(orig_keys,
1335
locations, unadded_keys, key_to_source_map)
1337
# We want to yield the keys in a semi-optimal (read-wise) ordering.
1338
# Otherwise we thrash the _group_cache and destroy performance
1339
source_keys = self._get_io_ordered_source_keys(locations,
1340
unadded_keys, source_result)
1342
yield AbsentContentFactory(key)
1344
last_read_memo = None
1345
# TODO: This works fairly well at batching up existing groups into a
1346
# streamable format, and possibly allowing for taking one big
1347
# group and splitting it when it isn't fully utilized.
1348
# However, it doesn't allow us to find under-utilized groups and
1349
# combine them into a bigger group on the fly.
1350
# (Consider the issue with how chk_map inserts texts
1351
# one-at-a-time.) This could be done at insert_record_stream()
1352
# time, but it probably would decrease the number of
1353
# bytes-on-the-wire for fetch.
1354
for source, keys in source_keys:
1357
if key in self._unadded_refs:
1358
if manager is not None:
1359
for factory in manager.get_record_stream():
1361
last_read_memo = manager = None
1362
bytes, sha1 = self._compressor.extract(key)
1363
parents = self._unadded_refs[key]
1364
yield FulltextContentFactory(key, parents, sha1, bytes)
1366
index_memo, _, parents, (method, _) = locations[key]
1367
read_memo = index_memo[0:3]
1368
if last_read_memo != read_memo:
1369
# We are starting a new block. If we have a
1370
# manager, we have found everything that fits for
1371
# now, so yield records
1372
if manager is not None:
1373
for factory in manager.get_record_stream():
1375
# Now start a new manager
1376
block = self._get_block(index_memo)
1377
manager = _LazyGroupContentManager(block)
1378
last_read_memo = read_memo
1379
start, end = index_memo[3:5]
1380
manager.add_factory(key, parents, start, end)
1382
if manager is not None:
1383
for factory in manager.get_record_stream():
1385
last_read_memo = manager = None
1386
for record in source.get_record_stream(keys, ordering,
1387
include_delta_closure):
1389
if manager is not None:
1390
for factory in manager.get_record_stream():
1393
def get_sha1s(self, keys):
1394
"""See VersionedFiles.get_sha1s()."""
1396
for record in self.get_record_stream(keys, 'unordered', True):
1397
if record.sha1 != None:
1398
result[record.key] = record.sha1
1400
if record.storage_kind != 'absent':
1401
result[record.key] = osutils.sha_string(
1402
record.get_bytes_as('fulltext'))
1405
def insert_record_stream(self, stream):
1406
"""Insert a record stream into this container.
1408
:param stream: A stream of records to insert.
1410
:seealso VersionedFiles.get_record_stream:
1412
# XXX: Setting random_id=True makes
1413
# test_insert_record_stream_existing_keys fail for groupcompress and
1414
# groupcompress-nograph, this needs to be revisited while addressing
1415
# 'bzr branch' performance issues.
1416
for _ in self._insert_record_stream(stream, random_id=False):
1419
def _insert_record_stream(self, stream, random_id=False, nostore_sha=None,
1421
"""Internal core to insert a record stream into this container.
1423
This helper function has a different interface than insert_record_stream
1424
to allow add_lines to be minimal, but still return the needed data.
1426
:param stream: A stream of records to insert.
1427
:param nostore_sha: If the sha1 of a given text matches nostore_sha,
1428
raise ExistingContent, rather than committing the new text.
1429
:param reuse_blocks: If the source is streaming from
1430
groupcompress-blocks, just insert the blocks as-is, rather than
1431
expanding the texts and inserting again.
1432
:return: An iterator over the sha1 of the inserted records.
1433
:seealso insert_record_stream:
1437
def get_adapter(adapter_key):
1439
return adapters[adapter_key]
1441
adapter_factory = adapter_registry.get(adapter_key)
1442
adapter = adapter_factory(self)
1443
adapters[adapter_key] = adapter
1445
# This will go up to fulltexts for gc to gc fetching, which isn't
1447
self._compressor = GroupCompressor()
1448
self._unadded_refs = {}
1451
bytes = self._compressor.flush().to_bytes()
1452
index, start, length = self._access.add_raw_records(
1453
[(None, len(bytes))], bytes)[0]
1455
for key, reads, refs in keys_to_add:
1456
nodes.append((key, "%d %d %s" % (start, length, reads), refs))
1457
self._index.add_records(nodes, random_id=random_id)
1458
self._unadded_refs = {}
1460
self._compressor = GroupCompressor()
1463
max_fulltext_len = 0
1464
max_fulltext_prefix = None
1465
insert_manager = None
1468
# XXX: TODO: remove this, it is just for safety checking for now
1469
inserted_keys = set()
1470
for record in stream:
1471
# Raise an error when a record is missing.
1472
if record.storage_kind == 'absent':
1473
raise errors.RevisionNotPresent(record.key, self)
1475
if record.key in inserted_keys:
1476
trace.note('Insert claimed random_id=True,'
1477
' but then inserted %r two times', record.key)
1479
inserted_keys.add(record.key)
1481
# If the reuse_blocks flag is set, check to see if we can just
1482
# copy a groupcompress block as-is.
1483
if record.storage_kind == 'groupcompress-block':
1484
# Insert the raw block into the target repo
1485
insert_manager = record._manager
1486
insert_manager._check_rebuild_block()
1487
bytes = record._manager._block.to_bytes()
1488
_, start, length = self._access.add_raw_records(
1489
[(None, len(bytes))], bytes)[0]
1492
block_length = length
1493
if record.storage_kind in ('groupcompress-block',
1494
'groupcompress-block-ref'):
1495
if insert_manager is None:
1496
raise AssertionError('No insert_manager set')
1497
value = "%d %d %d %d" % (block_start, block_length,
1498
record._start, record._end)
1499
nodes = [(record.key, value, (record.parents,))]
1500
# TODO: Consider buffering up many nodes to be added, not
1501
# sure how much overhead this has, but we're seeing
1502
# ~23s / 120s in add_records calls
1503
self._index.add_records(nodes, random_id=random_id)
1506
bytes = record.get_bytes_as('fulltext')
1507
except errors.UnavailableRepresentation:
1508
adapter_key = record.storage_kind, 'fulltext'
1509
adapter = get_adapter(adapter_key)
1510
bytes = adapter.get_bytes(record)
1511
if len(record.key) > 1:
1512
prefix = record.key[0]
1513
soft = (prefix == last_prefix)
1517
if max_fulltext_len < len(bytes):
1518
max_fulltext_len = len(bytes)
1519
max_fulltext_prefix = prefix
1520
(found_sha1, start_point, end_point,
1521
type) = self._compressor.compress(record.key,
1522
bytes, record.sha1, soft=soft,
1523
nostore_sha=nostore_sha)
1524
# delta_ratio = float(len(bytes)) / (end_point - start_point)
1525
# Check if we want to continue to include that text
1526
if (prefix == max_fulltext_prefix
1527
and end_point < 2 * max_fulltext_len):
1528
# As long as we are on the same file_id, we will fill at least
1529
# 2 * max_fulltext_len
1530
start_new_block = False
1531
elif end_point > 4*1024*1024:
1532
start_new_block = True
1533
elif (prefix is not None and prefix != last_prefix
1534
and end_point > 2*1024*1024):
1535
start_new_block = True
1537
start_new_block = False
1538
last_prefix = prefix
1540
self._compressor.pop_last()
1542
max_fulltext_len = len(bytes)
1543
(found_sha1, start_point, end_point,
1544
type) = self._compressor.compress(record.key, bytes,
1546
if record.key[-1] is None:
1547
key = record.key[:-1] + ('sha1:' + found_sha1,)
1550
self._unadded_refs[key] = record.parents
1552
keys_to_add.append((key, '%d %d' % (start_point, end_point),
1554
if len(keys_to_add):
1556
self._compressor = None
1558
def iter_lines_added_or_present_in_keys(self, keys, pb=None):
1559
"""Iterate over the lines in the versioned files from keys.
1561
This may return lines from other keys. Each item the returned
1562
iterator yields is a tuple of a line and a text version that that line
1563
is present in (not introduced in).
1565
Ordering of results is in whatever order is most suitable for the
1566
underlying storage format.
1568
If a progress bar is supplied, it may be used to indicate progress.
1569
The caller is responsible for cleaning up progress bars (because this
1573
* Lines are normalised by the underlying store: they will all have \n
1575
* Lines are returned in arbitrary order.
1577
:return: An iterator over (line, key).
1581
# we don't care about inclusions, the caller cares.
1582
# but we need to setup a list of records to visit.
1583
# we need key, position, length
1584
for key_idx, record in enumerate(self.get_record_stream(keys,
1585
'unordered', True)):
1586
# XXX: todo - optimise to use less than full texts.
1589
pb.update('Walking content', key_idx, total)
1590
if record.storage_kind == 'absent':
1591
raise errors.RevisionNotPresent(key, self)
1592
lines = osutils.split_lines(record.get_bytes_as('fulltext'))
1596
pb.update('Walking content', total, total)
1599
"""See VersionedFiles.keys."""
1600
if 'evil' in debug.debug_flags:
1601
trace.mutter_callsite(2, "keys scales with size of history")
1602
sources = [self._index] + self._fallback_vfs
1604
for source in sources:
1605
result.update(source.keys())
1609
class _GCGraphIndex(object):
1610
"""Mapper from GroupCompressVersionedFiles needs into GraphIndex storage."""
1612
def __init__(self, graph_index, is_locked, parents=True,
1613
add_callback=None, track_external_parent_refs=False):
1614
"""Construct a _GCGraphIndex on a graph_index.
1616
:param graph_index: An implementation of bzrlib.index.GraphIndex.
1617
:param is_locked: A callback, returns True if the index is locked and
1619
:param parents: If True, record knits parents, if not do not record
1621
:param add_callback: If not None, allow additions to the index and call
1622
this callback with a list of added GraphIndex nodes:
1623
[(node, value, node_refs), ...]
1624
:param track_external_parent_refs: As keys are added, keep track of the
1625
keys they reference, so that we can query get_missing_parents(),
1628
self._add_callback = add_callback
1629
self._graph_index = graph_index
1630
self._parents = parents
1631
self.has_graph = parents
1632
self._is_locked = is_locked
1633
if track_external_parent_refs:
1634
self._key_dependencies = knit._KeyRefs()
1636
self._key_dependencies = None
1638
def add_records(self, records, random_id=False):
1639
"""Add multiple records to the index.
1641
This function does not insert data into the Immutable GraphIndex
1642
backing the KnitGraphIndex, instead it prepares data for insertion by
1643
the caller and checks that it is safe to insert then calls
1644
self._add_callback with the prepared GraphIndex nodes.
1646
:param records: a list of tuples:
1647
(key, options, access_memo, parents).
1648
:param random_id: If True the ids being added were randomly generated
1649
and no check for existence will be performed.
1651
if not self._add_callback:
1652
raise errors.ReadOnlyError(self)
1653
# we hope there are no repositories with inconsistent parentage
1658
for (key, value, refs) in records:
1659
if not self._parents:
1663
raise errors.KnitCorrupt(self,
1664
"attempt to add node with parents "
1665
"in parentless index.")
1668
keys[key] = (value, refs)
1671
present_nodes = self._get_entries(keys)
1672
for (index, key, value, node_refs) in present_nodes:
1673
if node_refs != keys[key][1]:
1674
raise errors.KnitCorrupt(self, "inconsistent details in add_records"
1675
": %s %s" % ((value, node_refs), keys[key]))
1681
for key, (value, node_refs) in keys.iteritems():
1682
result.append((key, value, node_refs))
1684
for key, (value, node_refs) in keys.iteritems():
1685
result.append((key, value))
1687
key_dependencies = self._key_dependencies
1688
if key_dependencies is not None and self._parents:
1689
for key, value, refs in records:
1691
key_dependencies.add_references(key, parents)
1692
self._add_callback(records)
1694
def _check_read(self):
1695
"""Raise an exception if reads are not permitted."""
1696
if not self._is_locked():
1697
raise errors.ObjectNotLocked(self)
1699
def _check_write_ok(self):
1700
"""Raise an exception if writes are not permitted."""
1701
if not self._is_locked():
1702
raise errors.ObjectNotLocked(self)
1704
def _get_entries(self, keys, check_present=False):
1705
"""Get the entries for keys.
1707
Note: Callers are responsible for checking that the index is locked
1708
before calling this method.
1710
:param keys: An iterable of index key tuples.
1715
for node in self._graph_index.iter_entries(keys):
1717
found_keys.add(node[1])
1719
# adapt parentless index to the rest of the code.
1720
for node in self._graph_index.iter_entries(keys):
1721
yield node[0], node[1], node[2], ()
1722
found_keys.add(node[1])
1724
missing_keys = keys.difference(found_keys)
1726
raise errors.RevisionNotPresent(missing_keys.pop(), self)
1728
def get_parent_map(self, keys):
1729
"""Get a map of the parents of keys.
1731
:param keys: The keys to look up parents for.
1732
:return: A mapping from keys to parents. Absent keys are absent from
1736
nodes = self._get_entries(keys)
1740
result[node[1]] = node[3][0]
1743
result[node[1]] = None
1746
def get_missing_parents(self):
1747
"""Return the keys of missing parents."""
1748
# Copied from _KnitGraphIndex.get_missing_parents
1749
# We may have false positives, so filter those out.
1750
self._key_dependencies.add_keys(
1751
self.get_parent_map(self._key_dependencies.get_unsatisfied_refs()))
1752
return frozenset(self._key_dependencies.get_unsatisfied_refs())
1754
def get_build_details(self, keys):
1755
"""Get the various build details for keys.
1757
Ghosts are omitted from the result.
1759
:param keys: An iterable of keys.
1760
:return: A dict of key:
1761
(index_memo, compression_parent, parents, record_details).
1763
opaque structure to pass to read_records to extract the raw
1766
Content that this record is built upon, may be None
1768
Logical parents of this node
1770
extra information about the content which needs to be passed to
1771
Factory.parse_record
1775
entries = self._get_entries(keys)
1776
for entry in entries:
1778
if not self._parents:
1781
parents = entry[3][0]
1783
result[key] = (self._node_to_position(entry),
1784
None, parents, (method, None))
1788
"""Get all the keys in the collection.
1790
The keys are not ordered.
1793
return [node[1] for node in self._graph_index.iter_all_entries()]
1795
def _node_to_position(self, node):
1796
"""Convert an index value to position details."""
1797
bits = node[2].split(' ')
1798
# It would be nice not to read the entire gzip.
1799
start = int(bits[0])
1801
basis_end = int(bits[2])
1802
delta_end = int(bits[3])
1803
return node[0], start, stop, basis_end, delta_end
1805
def scan_unvalidated_index(self, graph_index):
1806
"""Inform this _GCGraphIndex that there is an unvalidated index.
1808
This allows this _GCGraphIndex to keep track of any missing
1809
compression parents we may want to have filled in to make those
1812
:param graph_index: A GraphIndex
1814
if self._key_dependencies is not None:
1815
# Add parent refs from graph_index (and discard parent refs that
1816
# the graph_index has).
1817
add_refs = self._key_dependencies.add_references
1818
for node in graph_index.iter_all_entries():
1819
add_refs(node[1], node[3][0])
1823
from bzrlib._groupcompress_py import (
1825
apply_delta_to_source,
1828
decode_copy_instruction,
1832
from bzrlib._groupcompress_pyx import (
1834
apply_delta_to_source,
1839
GroupCompressor = PyrexGroupCompressor
1841
GroupCompressor = PythonGroupCompressor
added
removed
bzrlib/groupcompress.py
