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# Copyright (C) 2005, 2006, 2007 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""Knit versionedfile implementation.
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A knit is a versioned file implementation that supports efficient append only
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lifeless: the data file is made up of "delta records". each delta record has a delta header
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that contains; (1) a version id, (2) the size of the delta (in lines), and (3) the digest of
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the -expanded data- (ie, the delta applied to the parent). the delta also ends with a
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end-marker; simply "end VERSION"
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delta can be line or full contents.a
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... the 8's there are the index number of the annotation.
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version robertc@robertcollins.net-20051003014215-ee2990904cc4c7ad 7 c7d23b2a5bd6ca00e8e266cec0ec228158ee9f9e
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8 e.set('executable', 'yes')
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8 if elt.get('executable') == 'yes':
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8 ie.executable = True
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end robertc@robertcollins.net-20051003014215-ee2990904cc4c7ad
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09:33 < jrydberg> lifeless: each index is made up of a tuple of; version id, options, position, size, parents
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09:33 < jrydberg> lifeless: the parents are currently dictionary compressed
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09:33 < jrydberg> lifeless: (meaning it currently does not support ghosts)
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09:33 < lifeless> right
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09:33 < jrydberg> lifeless: the position and size is the range in the data file
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so the index sequence is the dictionary compressed sequence number used
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in the deltas to provide line annotation
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# 10:16 < lifeless> make partial index writes safe
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# 10:16 < lifeless> implement 'knit.check()' like weave.check()
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# 10:17 < lifeless> record known ghosts so we can detect when they are filled in rather than the current 'reweave
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# move sha1 out of the content so that join is faster at verifying parents
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# record content length ?
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from cStringIO import StringIO
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from itertools import izip, chain
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from bzrlib.lazy_import import lazy_import
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lazy_import(globals(), """
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from bzrlib.errors import (
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RevisionAlreadyPresent,
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from bzrlib.tuned_gzip import GzipFile
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from bzrlib.trace import mutter
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from bzrlib.osutils import (
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from bzrlib.symbol_versioning import DEPRECATED_PARAMETER, deprecated_passed
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from bzrlib.tsort import topo_sort
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from bzrlib.versionedfile import VersionedFile, InterVersionedFile
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# TODO: Split out code specific to this format into an associated object.
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# TODO: Can we put in some kind of value to check that the index and data
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# files belong together?
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# TODO: accommodate binaries, perhaps by storing a byte count
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# TODO: function to check whole file
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# TODO: atomically append data, then measure backwards from the cursor
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# position after writing to work out where it was located. we may need to
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# bypass python file buffering.
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DATA_SUFFIX = '.knit'
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INDEX_SUFFIX = '.kndx'
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class KnitContent(object):
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"""Content of a knit version to which deltas can be applied."""
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def __init__(self, lines):
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def annotate_iter(self):
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"""Yield tuples of (origin, text) for each content line."""
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return iter(self._lines)
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"""Return a list of (origin, text) tuples."""
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return list(self.annotate_iter())
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def line_delta_iter(self, new_lines):
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"""Generate line-based delta from this content to new_lines."""
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new_texts = new_lines.text()
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old_texts = self.text()
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s = KnitSequenceMatcher(None, old_texts, new_texts)
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for tag, i1, i2, j1, j2 in s.get_opcodes():
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# ofrom, oto, length, data
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yield i1, i2, j2 - j1, new_lines._lines[j1:j2]
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def line_delta(self, new_lines):
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return list(self.line_delta_iter(new_lines))
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return [text for origin, text in self._lines]
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return KnitContent(self._lines[:])
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def get_line_delta_blocks(knit_delta, source, target):
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"""Extract SequenceMatcher.get_matching_blocks() from a knit delta"""
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target_len = len(target)
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for s_begin, s_end, t_len, new_text in knit_delta:
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true_n = s_begin - s_pos
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# knit deltas do not provide reliable info about whether the
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# last line of a file matches, due to eol handling.
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if source[s_pos + n -1] != target[t_pos + n -1]:
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yield s_pos, t_pos, n
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t_pos += t_len + true_n
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n = target_len - t_pos
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if source[s_pos + n -1] != target[t_pos + n -1]:
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yield s_pos, t_pos, n
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yield s_pos + (target_len - t_pos), target_len, 0
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class _KnitFactory(object):
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"""Base factory for creating content objects."""
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def make(self, lines, version_id):
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num_lines = len(lines)
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return KnitContent(zip([version_id] * num_lines, lines))
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class KnitAnnotateFactory(_KnitFactory):
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"""Factory for creating annotated Content objects."""
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def parse_fulltext(self, content, version_id):
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"""Convert fulltext to internal representation
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fulltext content is of the format
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revid(utf8) plaintext\n
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internal representation is of the format:
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# TODO: jam 20070209 The tests expect this to be returned as tuples,
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# but the code itself doesn't really depend on that.
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# Figure out a way to not require the overhead of turning the
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# list back into tuples.
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lines = [tuple(line.split(' ', 1)) for line in content]
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return KnitContent(lines)
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def parse_line_delta_iter(self, lines):
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return iter(self.parse_line_delta(lines))
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def parse_line_delta(self, lines, version_id):
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"""Convert a line based delta into internal representation.
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line delta is in the form of:
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intstart intend intcount
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revid(utf8) newline\n
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internal representation is
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(start, end, count, [1..count tuples (revid, newline)])
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def cache_and_return(line):
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origin, text = line.split(' ', 1)
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return cache.setdefault(origin, origin), text
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# walk through the lines parsing.
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start, end, count = [int(n) for n in header.split(',')]
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contents = [tuple(next().split(' ', 1)) for i in xrange(count)]
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result.append((start, end, count, contents))
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def get_fulltext_content(self, lines):
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"""Extract just the content lines from a fulltext."""
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return (line.split(' ', 1)[1] for line in lines)
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def get_linedelta_content(self, lines):
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"""Extract just the content from a line delta.
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This doesn't return all of the extra information stored in a delta.
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Only the actual content lines.
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header = header.split(',')
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count = int(header[2])
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for i in xrange(count):
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origin, text = next().split(' ', 1)
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def lower_fulltext(self, content):
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"""convert a fulltext content record into a serializable form.
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see parse_fulltext which this inverts.
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# TODO: jam 20070209 We only do the caching thing to make sure that
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# the origin is a valid utf-8 line, eventually we could remove it
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return ['%s %s' % (o, t) for o, t in content._lines]
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def lower_line_delta(self, delta):
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"""convert a delta into a serializable form.
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See parse_line_delta which this inverts.
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# TODO: jam 20070209 We only do the caching thing to make sure that
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# the origin is a valid utf-8 line, eventually we could remove it
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for start, end, c, lines in delta:
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out.append('%d,%d,%d\n' % (start, end, c))
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out.extend(origin + ' ' + text
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for origin, text in lines)
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class KnitPlainFactory(_KnitFactory):
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"""Factory for creating plain Content objects."""
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def parse_fulltext(self, content, version_id):
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"""This parses an unannotated fulltext.
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Note that this is not a noop - the internal representation
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has (versionid, line) - its just a constant versionid.
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return self.make(content, version_id)
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def parse_line_delta_iter(self, lines, version_id):
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num_lines = len(lines)
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while cur < num_lines:
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start, end, c = [int(n) for n in header.split(',')]
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yield start, end, c, zip([version_id] * c, lines[cur:cur+c])
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def parse_line_delta(self, lines, version_id):
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return list(self.parse_line_delta_iter(lines, version_id))
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def get_fulltext_content(self, lines):
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"""Extract just the content lines from a fulltext."""
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def get_linedelta_content(self, lines):
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"""Extract just the content from a line delta.
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This doesn't return all of the extra information stored in a delta.
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Only the actual content lines.
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header = header.split(',')
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count = int(header[2])
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for i in xrange(count):
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def lower_fulltext(self, content):
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return content.text()
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def lower_line_delta(self, delta):
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for start, end, c, lines in delta:
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out.append('%d,%d,%d\n' % (start, end, c))
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out.extend([text for origin, text in lines])
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def make_empty_knit(transport, relpath):
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"""Construct a empty knit at the specified location."""
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k = KnitVersionedFile(transport, relpath, 'w', KnitPlainFactory)
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class KnitVersionedFile(VersionedFile):
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"""Weave-like structure with faster random access.
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A knit stores a number of texts and a summary of the relationships
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between them. Texts are identified by a string version-id. Texts
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are normally stored and retrieved as a series of lines, but can
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also be passed as single strings.
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Lines are stored with the trailing newline (if any) included, to
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avoid special cases for files with no final newline. Lines are
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composed of 8-bit characters, not unicode. The combination of
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these approaches should mean any 'binary' file can be safely
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stored and retrieved.
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def __init__(self, relpath, transport, file_mode=None, access_mode=None,
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factory=None, basis_knit=DEPRECATED_PARAMETER, delta=True,
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create=False, create_parent_dir=False, delay_create=False,
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dir_mode=None, index=None, access_method=None):
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"""Construct a knit at location specified by relpath.
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:param create: If not True, only open an existing knit.
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:param create_parent_dir: If True, create the parent directory if
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creating the file fails. (This is used for stores with
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hash-prefixes that may not exist yet)
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:param delay_create: The calling code is aware that the knit won't
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actually be created until the first data is stored.
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:param index: An index to use for the knit.
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if deprecated_passed(basis_knit):
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warnings.warn("KnitVersionedFile.__(): The basis_knit parameter is"
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" deprecated as of bzr 0.9.",
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DeprecationWarning, stacklevel=2)
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if access_mode is None:
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super(KnitVersionedFile, self).__init__(access_mode)
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assert access_mode in ('r', 'w'), "invalid mode specified %r" % access_mode
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self.transport = transport
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self.filename = relpath
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self.factory = factory or KnitAnnotateFactory()
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self.writable = (access_mode == 'w')
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self._max_delta_chain = 200
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self._index = _KnitIndex(transport, relpath + INDEX_SUFFIX,
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access_mode, create=create, file_mode=file_mode,
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create_parent_dir=create_parent_dir, delay_create=delay_create,
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if access_method is None:
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_access = _KnitAccess(transport, relpath + DATA_SUFFIX, file_mode, dir_mode,
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((create and not len(self)) and delay_create), create_parent_dir)
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_access = access_method
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if create and not len(self) and not delay_create:
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self._data = _KnitData(_access)
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return '%s(%s)' % (self.__class__.__name__,
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self.transport.abspath(self.filename))
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def _check_should_delta(self, first_parents):
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"""Iterate back through the parent listing, looking for a fulltext.
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This is used when we want to decide whether to add a delta or a new
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fulltext. It searches for _max_delta_chain parents. When it finds a
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fulltext parent, it sees if the total size of the deltas leading up to
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it is large enough to indicate that we want a new full text anyway.
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Return True if we should create a new delta, False if we should use a
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delta_parents = first_parents
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for count in xrange(self._max_delta_chain):
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parent = delta_parents[0]
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method = self._index.get_method(parent)
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index, pos, size = self._index.get_position(parent)
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if method == 'fulltext':
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delta_parents = self._index.get_parents(parent)
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# We couldn't find a fulltext, so we must create a new one
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return fulltext_size > delta_size
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def _add_delta(self, version_id, parents, delta_parent, sha1, noeol, delta):
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"""See VersionedFile._add_delta()."""
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self._check_add(version_id, []) # should we check the lines ?
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self._check_versions_present(parents)
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for parent in parents:
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if not self.has_version(parent):
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ghosts.append(parent)
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present_parents.append(parent)
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if delta_parent is None:
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# reconstitute as full text.
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assert len(delta) == 1 or len(delta) == 0
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assert delta[0][0] == 0
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assert delta[0][1] == 0, delta[0][1]
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return super(KnitVersionedFile, self)._add_delta(version_id,
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options.append('no-eol')
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if delta_parent is not None:
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# determine the current delta chain length.
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# To speed the extract of texts the delta chain is limited
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# to a fixed number of deltas. This should minimize both
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# I/O and the time spend applying deltas.
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# The window was changed to a maximum of 200 deltas, but also added
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# was a check that the total compressed size of the deltas is
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# smaller than the compressed size of the fulltext.
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if not self._check_should_delta([delta_parent]):
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# We don't want a delta here, just do a normal insertion.
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return super(KnitVersionedFile, self)._add_delta(version_id,
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options.append('line-delta')
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store_lines = self.factory.lower_line_delta(delta)
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access_memo = self._data.add_record(version_id, digest, store_lines)
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self._index.add_version(version_id, options, access_memo, parents)
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def _add_raw_records(self, records, data):
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"""Add all the records 'records' with data pre-joined in 'data'.
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:param records: A list of tuples(version_id, options, parents, size).
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:param data: The data for the records. When it is written, the records
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are adjusted to have pos pointing into data by the sum of
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the preceding records sizes.
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raw_record_sizes = [record[3] for record in records]
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positions = self._data.add_raw_records(raw_record_sizes, data)
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for (version_id, options, parents, size), access_memo in zip(
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index_entries.append((version_id, options, access_memo, parents))
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if self._data._do_cache:
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self._data._cache[version_id] = data[offset:offset+size]
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self._index.add_versions(index_entries)
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def enable_cache(self):
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"""Start caching data for this knit"""
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self._data.enable_cache()
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def clear_cache(self):
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"""Clear the data cache only."""
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self._data.clear_cache()
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def copy_to(self, name, transport):
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"""See VersionedFile.copy_to()."""
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# copy the current index to a temp index to avoid racing with local
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transport.put_file_non_atomic(name + INDEX_SUFFIX + '.tmp',
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self.transport.get(self._index._filename))
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f = self._data._open_file()
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transport.put_file(name + DATA_SUFFIX, f)
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# move the copied index into place
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transport.move(name + INDEX_SUFFIX + '.tmp', name + INDEX_SUFFIX)
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def create_empty(self, name, transport, mode=None):
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return KnitVersionedFile(name, transport, factory=self.factory,
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delta=self.delta, create=True)
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def _fix_parents(self, version_id, new_parents):
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"""Fix the parents list for version.
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This is done by appending a new version to the index
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with identical data except for the parents list.
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the parents list must be a superset of the current
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current_values = self._index._cache[version_id]
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assert set(current_values[4]).difference(set(new_parents)) == set()
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self._index.add_version(version_id,
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(None, current_values[2], current_values[3]),
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def _extract_blocks(self, version_id, source, target):
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if self._index.get_method(version_id) != 'line-delta':
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parent, sha1, noeol, delta = self.get_delta(version_id)
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return KnitContent.get_line_delta_blocks(delta, source, target)
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def get_delta(self, version_id):
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"""Get a delta for constructing version from some other version."""
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version_id = osutils.safe_revision_id(version_id)
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self.check_not_reserved_id(version_id)
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if not self.has_version(version_id):
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raise RevisionNotPresent(version_id, self.filename)
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parents = self.get_parents(version_id)
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index_memo = self._index.get_position(version_id)
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data, sha1 = self._data.read_records(((version_id, index_memo),))[version_id]
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noeol = 'no-eol' in self._index.get_options(version_id)
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if 'fulltext' == self._index.get_method(version_id):
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new_content = self.factory.parse_fulltext(data, version_id)
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if parent is not None:
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reference_content = self._get_content(parent)
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old_texts = reference_content.text()
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new_texts = new_content.text()
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delta_seq = KnitSequenceMatcher(None, old_texts, new_texts)
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return parent, sha1, noeol, self._make_line_delta(delta_seq, new_content)
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delta = self.factory.parse_line_delta(data, version_id)
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return parent, sha1, noeol, delta
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def get_graph_with_ghosts(self):
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"""See VersionedFile.get_graph_with_ghosts()."""
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graph_items = self._index.get_graph()
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return dict(graph_items)
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def get_sha1(self, version_id):
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return self.get_sha1s([version_id])[0]
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def get_sha1s(self, version_ids):
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"""See VersionedFile.get_sha1()."""
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version_ids = [osutils.safe_revision_id(v) for v in version_ids]
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record_map = self._get_record_map(version_ids)
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# record entry 2 is the 'digest'.
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return [record_map[v][2] for v in version_ids]
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"""See VersionedFile.get_suffixes()."""
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return [DATA_SUFFIX, INDEX_SUFFIX]
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def has_ghost(self, version_id):
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"""True if there is a ghost reference in the file to version_id."""
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version_id = osutils.safe_revision_id(version_id)
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if self.has_version(version_id):
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# optimisable if needed by memoising the _ghosts set.
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items = self._index.get_graph()
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for node, parents in items:
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for parent in parents:
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if parent not in self._index._cache:
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if parent == version_id:
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"""See VersionedFile.versions."""
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return self._index.get_versions()
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def has_version(self, version_id):
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"""See VersionedFile.has_version."""
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version_id = osutils.safe_revision_id(version_id)
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return self._index.has_version(version_id)
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__contains__ = has_version
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def _merge_annotations(self, content, parents, parent_texts={},
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delta=None, annotated=None,
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left_matching_blocks=None):
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"""Merge annotations for content. This is done by comparing
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the annotations based on changed to the text.
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if left_matching_blocks is not None:
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delta_seq = diff._PrematchedMatcher(left_matching_blocks)
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for parent_id in parents:
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merge_content = self._get_content(parent_id, parent_texts)
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if (parent_id == parents[0] and delta_seq is not None):
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seq = patiencediff.PatienceSequenceMatcher(
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None, merge_content.text(), content.text())
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for i, j, n in seq.get_matching_blocks():
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# this appears to copy (origin, text) pairs across to the
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# new content for any line that matches the last-checked
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content._lines[j:j+n] = merge_content._lines[i:i+n]
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if delta_seq is None:
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reference_content = self._get_content(parents[0], parent_texts)
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new_texts = content.text()
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old_texts = reference_content.text()
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delta_seq = patiencediff.PatienceSequenceMatcher(
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None, old_texts, new_texts)
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return self._make_line_delta(delta_seq, content)
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def _make_line_delta(self, delta_seq, new_content):
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"""Generate a line delta from delta_seq and new_content."""
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for op in delta_seq.get_opcodes():
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diff_hunks.append((op[1], op[2], op[4]-op[3], new_content._lines[op[3]:op[4]]))
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def _get_components_positions(self, version_ids):
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"""Produce a map of position data for the components of versions.
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This data is intended to be used for retrieving the knit records.
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A dict of version_id to (method, data_pos, data_size, next) is
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method is the way referenced data should be applied.
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data_pos is the position of the data in the knit.
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data_size is the size of the data in the knit.
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next is the build-parent of the version, or None for fulltexts.
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for version_id in version_ids:
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while cursor is not None and cursor not in component_data:
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method = self._index.get_method(cursor)
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if method == 'fulltext':
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next = self.get_parents(cursor)[0]
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index_memo = self._index.get_position(cursor)
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component_data[cursor] = (method, index_memo, next)
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return component_data
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def _get_content(self, version_id, parent_texts={}):
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"""Returns a content object that makes up the specified
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if not self.has_version(version_id):
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raise RevisionNotPresent(version_id, self.filename)
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cached_version = parent_texts.get(version_id, None)
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if cached_version is not None:
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return cached_version
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text_map, contents_map = self._get_content_maps([version_id])
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return contents_map[version_id]
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def _check_versions_present(self, version_ids):
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"""Check that all specified versions are present."""
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self._index.check_versions_present(version_ids)
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def _add_lines_with_ghosts(self, version_id, parents, lines, parent_texts):
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"""See VersionedFile.add_lines_with_ghosts()."""
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self._check_add(version_id, lines)
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return self._add(version_id, lines[:], parents, self.delta, parent_texts)
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def _add_lines(self, version_id, parents, lines, parent_texts,
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left_matching_blocks=None):
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"""See VersionedFile.add_lines."""
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self._check_add(version_id, lines)
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self._check_versions_present(parents)
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return self._add(version_id, lines[:], parents, self.delta,
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parent_texts, left_matching_blocks)
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def _check_add(self, version_id, lines):
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"""check that version_id and lines are safe to add."""
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assert self.writable, "knit is not opened for write"
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### FIXME escape. RBC 20060228
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if contains_whitespace(version_id):
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raise InvalidRevisionId(version_id, self.filename)
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self.check_not_reserved_id(version_id)
751
if self.has_version(version_id):
752
raise RevisionAlreadyPresent(version_id, self.filename)
753
self._check_lines_not_unicode(lines)
754
self._check_lines_are_lines(lines)
756
def _add(self, version_id, lines, parents, delta, parent_texts,
757
left_matching_blocks=None):
758
"""Add a set of lines on top of version specified by parents.
760
If delta is true, compress the text as a line-delta against
763
Any versions not present will be converted into ghosts.
765
# 461 0 6546.0390 43.9100 bzrlib.knit:489(_add)
766
# +400 0 889.4890 418.9790 +bzrlib.knit:192(lower_fulltext)
767
# +461 0 1364.8070 108.8030 +bzrlib.knit:996(add_record)
768
# +461 0 193.3940 41.5720 +bzrlib.knit:898(add_version)
769
# +461 0 134.0590 18.3810 +bzrlib.osutils:361(sha_strings)
770
# +461 0 36.3420 15.4540 +bzrlib.knit:146(make)
771
# +1383 0 8.0370 8.0370 +<len>
772
# +61 0 13.5770 7.9190 +bzrlib.knit:199(lower_line_delta)
773
# +61 0 963.3470 7.8740 +bzrlib.knit:427(_get_content)
774
# +61 0 973.9950 5.2950 +bzrlib.knit:136(line_delta)
775
# +61 0 1918.1800 5.2640 +bzrlib.knit:359(_merge_annotations)
779
if parent_texts is None:
781
for parent in parents:
782
if not self.has_version(parent):
783
ghosts.append(parent)
785
present_parents.append(parent)
787
if delta and not len(present_parents):
790
digest = sha_strings(lines)
793
if lines[-1][-1] != '\n':
794
options.append('no-eol')
795
lines[-1] = lines[-1] + '\n'
797
if len(present_parents) and delta:
798
# To speed the extract of texts the delta chain is limited
799
# to a fixed number of deltas. This should minimize both
800
# I/O and the time spend applying deltas.
801
delta = self._check_should_delta(present_parents)
803
assert isinstance(version_id, str)
804
lines = self.factory.make(lines, version_id)
805
if delta or (self.factory.annotated and len(present_parents) > 0):
806
# Merge annotations from parent texts if so is needed.
807
delta_hunks = self._merge_annotations(lines, present_parents,
808
parent_texts, delta, self.factory.annotated,
809
left_matching_blocks)
812
options.append('line-delta')
813
store_lines = self.factory.lower_line_delta(delta_hunks)
815
options.append('fulltext')
816
store_lines = self.factory.lower_fulltext(lines)
818
access_memo = self._data.add_record(version_id, digest, store_lines)
819
self._index.add_version(version_id, options, access_memo, parents)
822
def check(self, progress_bar=None):
823
"""See VersionedFile.check()."""
825
def _clone_text(self, new_version_id, old_version_id, parents):
826
"""See VersionedFile.clone_text()."""
827
# FIXME RBC 20060228 make fast by only inserting an index with null
829
self.add_lines(new_version_id, parents, self.get_lines(old_version_id))
831
def get_lines(self, version_id):
832
"""See VersionedFile.get_lines()."""
833
return self.get_line_list([version_id])[0]
835
def _get_record_map(self, version_ids):
836
"""Produce a dictionary of knit records.
838
The keys are version_ids, the values are tuples of (method, content,
840
method is the way the content should be applied.
841
content is a KnitContent object.
842
digest is the SHA1 digest of this version id after all steps are done
843
next is the build-parent of the version, i.e. the leftmost ancestor.
844
If the method is fulltext, next will be None.
846
position_map = self._get_components_positions(version_ids)
847
# c = component_id, m = method, i_m = index_memo, n = next
848
records = [(c, i_m) for c, (m, i_m, n) in position_map.iteritems()]
850
for component_id, content, digest in \
851
self._data.read_records_iter(records):
852
method, index_memo, next = position_map[component_id]
853
record_map[component_id] = method, content, digest, next
857
def get_text(self, version_id):
858
"""See VersionedFile.get_text"""
859
return self.get_texts([version_id])[0]
861
def get_texts(self, version_ids):
862
return [''.join(l) for l in self.get_line_list(version_ids)]
864
def get_line_list(self, version_ids):
865
"""Return the texts of listed versions as a list of strings."""
866
version_ids = [osutils.safe_revision_id(v) for v in version_ids]
867
for version_id in version_ids:
868
self.check_not_reserved_id(version_id)
869
text_map, content_map = self._get_content_maps(version_ids)
870
return [text_map[v] for v in version_ids]
872
_get_lf_split_line_list = get_line_list
874
def _get_content_maps(self, version_ids):
875
"""Produce maps of text and KnitContents
877
:return: (text_map, content_map) where text_map contains the texts for
878
the requested versions and content_map contains the KnitContents.
879
Both dicts take version_ids as their keys.
881
for version_id in version_ids:
882
if not self.has_version(version_id):
883
raise RevisionNotPresent(version_id, self.filename)
884
record_map = self._get_record_map(version_ids)
889
for version_id in version_ids:
892
while cursor is not None:
893
method, data, digest, next = record_map[cursor]
894
components.append((cursor, method, data, digest))
895
if cursor in content_map:
900
for component_id, method, data, digest in reversed(components):
901
if component_id in content_map:
902
content = content_map[component_id]
904
if method == 'fulltext':
905
assert content is None
906
content = self.factory.parse_fulltext(data, version_id)
907
elif method == 'line-delta':
908
delta = self.factory.parse_line_delta(data, version_id)
909
content = content.copy()
910
content._lines = self._apply_delta(content._lines,
912
content_map[component_id] = content
914
if 'no-eol' in self._index.get_options(version_id):
915
content = content.copy()
916
line = content._lines[-1][1].rstrip('\n')
917
content._lines[-1] = (content._lines[-1][0], line)
918
final_content[version_id] = content
920
# digest here is the digest from the last applied component.
921
text = content.text()
922
if sha_strings(text) != digest:
923
raise KnitCorrupt(self.filename,
924
'sha-1 does not match %s' % version_id)
926
text_map[version_id] = text
927
return text_map, final_content
929
def iter_lines_added_or_present_in_versions(self, version_ids=None,
931
"""See VersionedFile.iter_lines_added_or_present_in_versions()."""
932
if version_ids is None:
933
version_ids = self.versions()
935
version_ids = [osutils.safe_revision_id(v) for v in version_ids]
937
pb = progress.DummyProgress()
938
# we don't care about inclusions, the caller cares.
939
# but we need to setup a list of records to visit.
940
# we need version_id, position, length
941
version_id_records = []
942
requested_versions = set(version_ids)
943
# filter for available versions
944
for version_id in requested_versions:
945
if not self.has_version(version_id):
946
raise RevisionNotPresent(version_id, self.filename)
947
# get a in-component-order queue:
948
for version_id in self.versions():
949
if version_id in requested_versions:
950
index_memo = self._index.get_position(version_id)
951
version_id_records.append((version_id, index_memo))
953
total = len(version_id_records)
954
for version_idx, (version_id, data, sha_value) in \
955
enumerate(self._data.read_records_iter(version_id_records)):
956
pb.update('Walking content.', version_idx, total)
957
method = self._index.get_method(version_id)
959
assert method in ('fulltext', 'line-delta')
960
if method == 'fulltext':
961
line_iterator = self.factory.get_fulltext_content(data)
963
line_iterator = self.factory.get_linedelta_content(data)
964
for line in line_iterator:
967
pb.update('Walking content.', total, total)
969
def iter_parents(self, version_ids):
970
"""Iterate through the parents for many version ids.
972
:param version_ids: An iterable yielding version_ids.
973
:return: An iterator that yields (version_id, parents). Requested
974
version_ids not present in the versioned file are simply skipped.
975
The order is undefined, allowing for different optimisations in
976
the underlying implementation.
978
version_ids = [osutils.safe_revision_id(version_id) for
979
version_id in version_ids]
980
return self._index.iter_parents(version_ids)
982
def num_versions(self):
983
"""See VersionedFile.num_versions()."""
984
return self._index.num_versions()
986
__len__ = num_versions
988
def annotate_iter(self, version_id):
989
"""See VersionedFile.annotate_iter."""
990
version_id = osutils.safe_revision_id(version_id)
991
content = self._get_content(version_id)
992
for origin, text in content.annotate_iter():
995
def get_parents(self, version_id):
996
"""See VersionedFile.get_parents."""
999
# 52554 calls in 1264 872 internal down from 3674
1000
version_id = osutils.safe_revision_id(version_id)
1002
return self._index.get_parents(version_id)
1004
raise RevisionNotPresent(version_id, self.filename)
1006
def get_parents_with_ghosts(self, version_id):
1007
"""See VersionedFile.get_parents."""
1008
version_id = osutils.safe_revision_id(version_id)
1010
return self._index.get_parents_with_ghosts(version_id)
1012
raise RevisionNotPresent(version_id, self.filename)
1014
def get_ancestry(self, versions, topo_sorted=True):
1015
"""See VersionedFile.get_ancestry."""
1016
if isinstance(versions, basestring):
1017
versions = [versions]
1020
versions = [osutils.safe_revision_id(v) for v in versions]
1021
return self._index.get_ancestry(versions, topo_sorted)
1023
def get_ancestry_with_ghosts(self, versions):
1024
"""See VersionedFile.get_ancestry_with_ghosts."""
1025
if isinstance(versions, basestring):
1026
versions = [versions]
1029
versions = [osutils.safe_revision_id(v) for v in versions]
1030
return self._index.get_ancestry_with_ghosts(versions)
1032
#@deprecated_method(zero_eight)
1033
def walk(self, version_ids):
1034
"""See VersionedFile.walk."""
1035
# We take the short path here, and extract all relevant texts
1036
# and put them in a weave and let that do all the work. Far
1037
# from optimal, but is much simpler.
1038
# FIXME RB 20060228 this really is inefficient!
1039
from bzrlib.weave import Weave
1041
w = Weave(self.filename)
1042
ancestry = set(self.get_ancestry(version_ids, topo_sorted=False))
1043
sorted_graph = topo_sort(self._index.get_graph())
1044
version_list = [vid for vid in sorted_graph if vid in ancestry]
1046
for version_id in version_list:
1047
lines = self.get_lines(version_id)
1048
w.add_lines(version_id, self.get_parents(version_id), lines)
1050
for lineno, insert_id, dset, line in w.walk(version_ids):
1051
yield lineno, insert_id, dset, line
1053
def plan_merge(self, ver_a, ver_b):
1054
"""See VersionedFile.plan_merge."""
1055
ver_a = osutils.safe_revision_id(ver_a)
1056
ver_b = osutils.safe_revision_id(ver_b)
1057
ancestors_b = set(self.get_ancestry(ver_b, topo_sorted=False))
1059
ancestors_a = set(self.get_ancestry(ver_a, topo_sorted=False))
1060
annotated_a = self.annotate(ver_a)
1061
annotated_b = self.annotate(ver_b)
1062
return merge._plan_annotate_merge(annotated_a, annotated_b,
1063
ancestors_a, ancestors_b)
1066
class _KnitComponentFile(object):
1067
"""One of the files used to implement a knit database"""
1069
def __init__(self, transport, filename, mode, file_mode=None,
1070
create_parent_dir=False, dir_mode=None):
1071
self._transport = transport
1072
self._filename = filename
1074
self._file_mode = file_mode
1075
self._dir_mode = dir_mode
1076
self._create_parent_dir = create_parent_dir
1077
self._need_to_create = False
1079
def _full_path(self):
1080
"""Return the full path to this file."""
1081
return self._transport.base + self._filename
1083
def check_header(self, fp):
1084
line = fp.readline()
1086
# An empty file can actually be treated as though the file doesn't
1088
raise errors.NoSuchFile(self._full_path())
1089
if line != self.HEADER:
1090
raise KnitHeaderError(badline=line,
1091
filename=self._transport.abspath(self._filename))
1094
return '%s(%s)' % (self.__class__.__name__, self._filename)
1097
class _KnitIndex(_KnitComponentFile):
1098
"""Manages knit index file.
1100
The index is already kept in memory and read on startup, to enable
1101
fast lookups of revision information. The cursor of the index
1102
file is always pointing to the end, making it easy to append
1105
_cache is a cache for fast mapping from version id to a Index
1108
_history is a cache for fast mapping from indexes to version ids.
1110
The index data format is dictionary compressed when it comes to
1111
parent references; a index entry may only have parents that with a
1112
lover index number. As a result, the index is topological sorted.
1114
Duplicate entries may be written to the index for a single version id
1115
if this is done then the latter one completely replaces the former:
1116
this allows updates to correct version and parent information.
1117
Note that the two entries may share the delta, and that successive
1118
annotations and references MUST point to the first entry.
1120
The index file on disc contains a header, followed by one line per knit
1121
record. The same revision can be present in an index file more than once.
1122
The first occurrence gets assigned a sequence number starting from 0.
1124
The format of a single line is
1125
REVISION_ID FLAGS BYTE_OFFSET LENGTH( PARENT_ID|PARENT_SEQUENCE_ID)* :\n
1126
REVISION_ID is a utf8-encoded revision id
1127
FLAGS is a comma separated list of flags about the record. Values include
1128
no-eol, line-delta, fulltext.
1129
BYTE_OFFSET is the ascii representation of the byte offset in the data file
1130
that the the compressed data starts at.
1131
LENGTH is the ascii representation of the length of the data file.
1132
PARENT_ID a utf-8 revision id prefixed by a '.' that is a parent of
1134
PARENT_SEQUENCE_ID the ascii representation of the sequence number of a
1135
revision id already in the knit that is a parent of REVISION_ID.
1136
The ' :' marker is the end of record marker.
1139
when a write is interrupted to the index file, it will result in a line
1140
that does not end in ' :'. If the ' :' is not present at the end of a line,
1141
or at the end of the file, then the record that is missing it will be
1142
ignored by the parser.
1144
When writing new records to the index file, the data is preceded by '\n'
1145
to ensure that records always start on new lines even if the last write was
1146
interrupted. As a result its normal for the last line in the index to be
1147
missing a trailing newline. One can be added with no harmful effects.
1150
HEADER = "# bzr knit index 8\n"
1152
# speed of knit parsing went from 280 ms to 280 ms with slots addition.
1153
# __slots__ = ['_cache', '_history', '_transport', '_filename']
1155
def _cache_version(self, version_id, options, pos, size, parents):
1156
"""Cache a version record in the history array and index cache.
1158
This is inlined into _load_data for performance. KEEP IN SYNC.
1159
(It saves 60ms, 25% of the __init__ overhead on local 4000 record
1162
# only want the _history index to reference the 1st index entry
1164
if version_id not in self._cache:
1165
index = len(self._history)
1166
self._history.append(version_id)
1168
index = self._cache[version_id][5]
1169
self._cache[version_id] = (version_id,
1176
def __init__(self, transport, filename, mode, create=False, file_mode=None,
1177
create_parent_dir=False, delay_create=False, dir_mode=None):
1178
_KnitComponentFile.__init__(self, transport, filename, mode,
1179
file_mode=file_mode,
1180
create_parent_dir=create_parent_dir,
1183
# position in _history is the 'official' index for a revision
1184
# but the values may have come from a newer entry.
1185
# so - wc -l of a knit index is != the number of unique names
1189
fp = self._transport.get(self._filename)
1191
# _load_data may raise NoSuchFile if the target knit is
1193
_load_data(self, fp)
1197
if mode != 'w' or not create:
1200
self._need_to_create = True
1202
self._transport.put_bytes_non_atomic(
1203
self._filename, self.HEADER, mode=self._file_mode)
1205
def get_graph(self):
1206
"""Return a list of the node:parents lists from this knit index."""
1207
return [(vid, idx[4]) for vid, idx in self._cache.iteritems()]
1209
def get_ancestry(self, versions, topo_sorted=True):
1210
"""See VersionedFile.get_ancestry."""
1211
# get a graph of all the mentioned versions:
1213
pending = set(versions)
1216
version = pending.pop()
1219
parents = [p for p in cache[version][4] if p in cache]
1221
raise RevisionNotPresent(version, self._filename)
1222
# if not completed and not a ghost
1223
pending.update([p for p in parents if p not in graph])
1224
graph[version] = parents
1227
return topo_sort(graph.items())
1229
def get_ancestry_with_ghosts(self, versions):
1230
"""See VersionedFile.get_ancestry_with_ghosts."""
1231
# get a graph of all the mentioned versions:
1232
self.check_versions_present(versions)
1235
pending = set(versions)
1237
version = pending.pop()
1239
parents = cache[version][4]
1245
pending.update([p for p in parents if p not in graph])
1246
graph[version] = parents
1247
return topo_sort(graph.items())
1249
def iter_parents(self, version_ids):
1250
"""Iterate through the parents for many version ids.
1252
:param version_ids: An iterable yielding version_ids.
1253
:return: An iterator that yields (version_id, parents). Requested
1254
version_ids not present in the versioned file are simply skipped.
1255
The order is undefined, allowing for different optimisations in
1256
the underlying implementation.
1258
for version_id in version_ids:
1260
yield version_id, tuple(self.get_parents(version_id))
1264
def num_versions(self):
1265
return len(self._history)
1267
__len__ = num_versions
1269
def get_versions(self):
1270
"""Get all the versions in the file. not topologically sorted."""
1271
return self._history
1273
def _version_list_to_index(self, versions):
1276
for version in versions:
1277
if version in cache:
1278
# -- inlined lookup() --
1279
result_list.append(str(cache[version][5]))
1280
# -- end lookup () --
1282
result_list.append('.' + version)
1283
return ' '.join(result_list)
1285
def add_version(self, version_id, options, index_memo, parents):
1286
"""Add a version record to the index."""
1287
self.add_versions(((version_id, options, index_memo, parents),))
1289
def add_versions(self, versions):
1290
"""Add multiple versions to the index.
1292
:param versions: a list of tuples:
1293
(version_id, options, pos, size, parents).
1296
orig_history = self._history[:]
1297
orig_cache = self._cache.copy()
1300
for version_id, options, (index, pos, size), parents in versions:
1301
line = "\n%s %s %s %s %s :" % (version_id,
1305
self._version_list_to_index(parents))
1306
assert isinstance(line, str), \
1307
'content must be utf-8 encoded: %r' % (line,)
1309
self._cache_version(version_id, options, pos, size, parents)
1310
if not self._need_to_create:
1311
self._transport.append_bytes(self._filename, ''.join(lines))
1314
sio.write(self.HEADER)
1315
sio.writelines(lines)
1317
self._transport.put_file_non_atomic(self._filename, sio,
1318
create_parent_dir=self._create_parent_dir,
1319
mode=self._file_mode,
1320
dir_mode=self._dir_mode)
1321
self._need_to_create = False
1323
# If any problems happen, restore the original values and re-raise
1324
self._history = orig_history
1325
self._cache = orig_cache
1328
def has_version(self, version_id):
1329
"""True if the version is in the index."""
1330
return version_id in self._cache
1332
def get_position(self, version_id):
1333
"""Return details needed to access the version.
1335
.kndx indices do not support split-out data, so return None for the
1338
:return: a tuple (None, data position, size) to hand to the access
1339
logic to get the record.
1341
entry = self._cache[version_id]
1342
return None, entry[2], entry[3]
1344
def get_method(self, version_id):
1345
"""Return compression method of specified version."""
1346
options = self._cache[version_id][1]
1347
if 'fulltext' in options:
1350
if 'line-delta' not in options:
1351
raise errors.KnitIndexUnknownMethod(self._full_path(), options)
1354
def get_options(self, version_id):
1355
"""Return a string represention options.
1359
return self._cache[version_id][1]
1361
def get_parents(self, version_id):
1362
"""Return parents of specified version ignoring ghosts."""
1363
return [parent for parent in self._cache[version_id][4]
1364
if parent in self._cache]
1366
def get_parents_with_ghosts(self, version_id):
1367
"""Return parents of specified version with ghosts."""
1368
return self._cache[version_id][4]
1370
def check_versions_present(self, version_ids):
1371
"""Check that all specified versions are present."""
1373
for version_id in version_ids:
1374
if version_id not in cache:
1375
raise RevisionNotPresent(version_id, self._filename)
1378
class KnitGraphIndex(object):
1379
"""A knit index that builds on GraphIndex."""
1381
def __init__(self, graph_index, deltas=False, parents=True, add_callback=None):
1382
"""Construct a KnitGraphIndex on a graph_index.
1384
:param graph_index: An implementation of bzrlib.index.GraphIndex.
1385
:param deltas: Allow delta-compressed records.
1386
:param add_callback: If not None, allow additions to the index and call
1387
this callback with a list of added GraphIndex nodes:
1388
[(node, value, node_refs), ...]
1389
:param parents: If True, record knits parents, if not do not record
1392
self._graph_index = graph_index
1393
self._deltas = deltas
1394
self._add_callback = add_callback
1395
self._parents = parents
1396
if deltas and not parents:
1397
raise KnitCorrupt(self, "Cannot do delta compression without "
1400
def _get_entries(self, keys, check_present=False):
1401
"""Get the entries for keys.
1403
:param keys: An iterable of index keys, - 1-tuples.
1408
for node in self._graph_index.iter_entries(keys):
1410
found_keys.add(node[1])
1412
# adapt parentless index to the rest of the code.
1413
for node in self._graph_index.iter_entries(keys):
1414
yield node[0], node[1], node[2], ()
1415
found_keys.add(node[1])
1417
missing_keys = keys.difference(found_keys)
1419
raise RevisionNotPresent(missing_keys.pop(), self)
1421
def _present_keys(self, version_ids):
1423
node[1] for node in self._get_entries(version_ids)])
1425
def _parentless_ancestry(self, versions):
1426
"""Honour the get_ancestry API for parentless knit indices."""
1427
wanted_keys = self._version_ids_to_keys(versions)
1428
present_keys = self._present_keys(wanted_keys)
1429
missing = set(wanted_keys).difference(present_keys)
1431
raise RevisionNotPresent(missing.pop(), self)
1432
return list(self._keys_to_version_ids(present_keys))
1434
def get_ancestry(self, versions, topo_sorted=True):
1435
"""See VersionedFile.get_ancestry."""
1436
if not self._parents:
1437
return self._parentless_ancestry(versions)
1438
# XXX: This will do len(history) index calls - perhaps
1439
# it should be altered to be a index core feature?
1440
# get a graph of all the mentioned versions:
1443
versions = self._version_ids_to_keys(versions)
1444
pending = set(versions)
1446
# get all pending nodes
1447
this_iteration = pending
1448
new_nodes = self._get_entries(this_iteration)
1451
for (index, key, value, node_refs) in new_nodes:
1452
# dont ask for ghosties - otherwise
1453
# we we can end up looping with pending
1454
# being entirely ghosted.
1455
graph[key] = [parent for parent in node_refs[0]
1456
if parent not in ghosts]
1458
for parent in graph[key]:
1459
# dont examine known nodes again
1464
ghosts.update(this_iteration.difference(found))
1465
if versions.difference(graph):
1466
raise RevisionNotPresent(versions.difference(graph).pop(), self)
1468
result_keys = topo_sort(graph.items())
1470
result_keys = graph.iterkeys()
1471
return [key[0] for key in result_keys]
1473
def get_ancestry_with_ghosts(self, versions):
1474
"""See VersionedFile.get_ancestry."""
1475
if not self._parents:
1476
return self._parentless_ancestry(versions)
1477
# XXX: This will do len(history) index calls - perhaps
1478
# it should be altered to be a index core feature?
1479
# get a graph of all the mentioned versions:
1481
versions = self._version_ids_to_keys(versions)
1482
pending = set(versions)
1484
# get all pending nodes
1485
this_iteration = pending
1486
new_nodes = self._get_entries(this_iteration)
1488
for (index, key, value, node_refs) in new_nodes:
1489
graph[key] = node_refs[0]
1491
for parent in graph[key]:
1492
# dont examine known nodes again
1496
missing_versions = this_iteration.difference(graph)
1497
missing_needed = versions.intersection(missing_versions)
1499
raise RevisionNotPresent(missing_needed.pop(), self)
1500
for missing_version in missing_versions:
1501
# add a key, no parents
1502
graph[missing_version] = []
1503
pending.discard(missing_version) # don't look for it
1504
result_keys = topo_sort(graph.items())
1505
return [key[0] for key in result_keys]
1507
def get_graph(self):
1508
"""Return a list of the node:parents lists from this knit index."""
1509
if not self._parents:
1510
return [(key, ()) for key in self.get_versions()]
1512
for index, key, value, refs in self._graph_index.iter_all_entries():
1513
result.append((key[0], tuple([ref[0] for ref in refs[0]])))
1516
def iter_parents(self, version_ids):
1517
"""Iterate through the parents for many version ids.
1519
:param version_ids: An iterable yielding version_ids.
1520
:return: An iterator that yields (version_id, parents). Requested
1521
version_ids not present in the versioned file are simply skipped.
1522
The order is undefined, allowing for different optimisations in
1523
the underlying implementation.
1526
all_nodes = set(self._get_entries(self._version_ids_to_keys(version_ids)))
1528
present_parents = set()
1529
for node in all_nodes:
1530
all_parents.update(node[3][0])
1531
# any node we are querying must be present
1532
present_parents.add(node[1])
1533
unknown_parents = all_parents.difference(present_parents)
1534
present_parents.update(self._present_keys(unknown_parents))
1535
for node in all_nodes:
1537
for parent in node[3][0]:
1538
if parent in present_parents:
1539
parents.append(parent[0])
1540
yield node[1][0], tuple(parents)
1542
for node in self._get_entries(self._version_ids_to_keys(version_ids)):
1543
yield node[1][0], ()
1545
def num_versions(self):
1546
return len(list(self._graph_index.iter_all_entries()))
1548
__len__ = num_versions
1550
def get_versions(self):
1551
"""Get all the versions in the file. not topologically sorted."""
1552
return [node[1][0] for node in self._graph_index.iter_all_entries()]
1554
def has_version(self, version_id):
1555
"""True if the version is in the index."""
1556
return len(self._present_keys(self._version_ids_to_keys([version_id]))) == 1
1558
def _keys_to_version_ids(self, keys):
1559
return tuple(key[0] for key in keys)
1561
def get_position(self, version_id):
1562
"""Return details needed to access the version.
1564
:return: a tuple (index, data position, size) to hand to the access
1565
logic to get the record.
1567
node = self._get_node(version_id)
1568
bits = node[2][1:].split(' ')
1569
return node[0], int(bits[0]), int(bits[1])
1571
def get_method(self, version_id):
1572
"""Return compression method of specified version."""
1573
if not self._deltas:
1575
return self._parent_compression(self._get_node(version_id)[3][1])
1577
def _parent_compression(self, reference_list):
1578
# use the second reference list to decide if this is delta'd or not.
1579
if len(reference_list):
1584
def _get_node(self, version_id):
1585
return list(self._get_entries(self._version_ids_to_keys([version_id])))[0]
1587
def get_options(self, version_id):
1588
"""Return a string represention options.
1592
node = self._get_node(version_id)
1593
if not self._deltas:
1594
options = ['fulltext']
1596
options = [self._parent_compression(node[3][1])]
1597
if node[2][0] == 'N':
1598
options.append('no-eol')
1601
def get_parents(self, version_id):
1602
"""Return parents of specified version ignoring ghosts."""
1603
parents = list(self.iter_parents([version_id]))
1606
raise errors.RevisionNotPresent(version_id, self)
1607
return parents[0][1]
1609
def get_parents_with_ghosts(self, version_id):
1610
"""Return parents of specified version with ghosts."""
1611
nodes = list(self._get_entries(self._version_ids_to_keys([version_id]),
1612
check_present=True))
1613
if not self._parents:
1615
return self._keys_to_version_ids(nodes[0][3][0])
1617
def check_versions_present(self, version_ids):
1618
"""Check that all specified versions are present."""
1619
keys = self._version_ids_to_keys(version_ids)
1620
present = self._present_keys(keys)
1621
missing = keys.difference(present)
1623
raise RevisionNotPresent(missing.pop(), self)
1625
def add_version(self, version_id, options, access_memo, parents):
1626
"""Add a version record to the index."""
1627
return self.add_versions(((version_id, options, access_memo, parents),))
1629
def add_versions(self, versions):
1630
"""Add multiple versions to the index.
1632
This function does not insert data into the Immutable GraphIndex
1633
backing the KnitGraphIndex, instead it prepares data for insertion by
1634
the caller and checks that it is safe to insert then calls
1635
self._add_callback with the prepared GraphIndex nodes.
1637
:param versions: a list of tuples:
1638
(version_id, options, pos, size, parents).
1640
if not self._add_callback:
1641
raise errors.ReadOnlyError(self)
1642
# we hope there are no repositories with inconsistent parentage
1647
for (version_id, options, access_memo, parents) in versions:
1648
index, pos, size = access_memo
1649
key = (version_id, )
1650
parents = tuple((parent, ) for parent in parents)
1651
if 'no-eol' in options:
1655
value += "%d %d" % (pos, size)
1656
if not self._deltas:
1657
if 'line-delta' in options:
1658
raise KnitCorrupt(self, "attempt to add line-delta in non-delta knit")
1661
if 'line-delta' in options:
1662
node_refs = (parents, (parents[0],))
1664
node_refs = (parents, ())
1666
node_refs = (parents, )
1669
raise KnitCorrupt(self, "attempt to add node with parents "
1670
"in parentless index.")
1672
keys[key] = (value, node_refs)
1673
present_nodes = self._get_entries(keys)
1674
for (index, key, value, node_refs) in present_nodes:
1675
if (value, node_refs) != keys[key]:
1676
raise KnitCorrupt(self, "inconsistent details in add_versions"
1677
": %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))
1686
self._add_callback(result)
1688
def _version_ids_to_keys(self, version_ids):
1689
return set((version_id, ) for version_id in version_ids)
1692
class _KnitAccess(object):
1693
"""Access to knit records in a .knit file."""
1695
def __init__(self, transport, filename, _file_mode, _dir_mode,
1696
_need_to_create, _create_parent_dir):
1697
"""Create a _KnitAccess for accessing and inserting data.
1699
:param transport: The transport the .knit is located on.
1700
:param filename: The filename of the .knit.
1702
self._transport = transport
1703
self._filename = filename
1704
self._file_mode = _file_mode
1705
self._dir_mode = _dir_mode
1706
self._need_to_create = _need_to_create
1707
self._create_parent_dir = _create_parent_dir
1709
def add_raw_records(self, sizes, raw_data):
1710
"""Add raw knit bytes to a storage area.
1712
The data is spooled to whereever the access method is storing data.
1714
:param sizes: An iterable containing the size of each raw data segment.
1715
:param raw_data: A bytestring containing the data.
1716
:return: A list of memos to retrieve the record later. Each memo is a
1717
tuple - (index, pos, length), where the index field is always None
1718
for the .knit access method.
1720
assert type(raw_data) == str, \
1721
'data must be plain bytes was %s' % type(raw_data)
1722
if not self._need_to_create:
1723
base = self._transport.append_bytes(self._filename, raw_data)
1725
self._transport.put_bytes_non_atomic(self._filename, raw_data,
1726
create_parent_dir=self._create_parent_dir,
1727
mode=self._file_mode,
1728
dir_mode=self._dir_mode)
1729
self._need_to_create = False
1733
result.append((None, base, size))
1738
"""IFF this data access has its own storage area, initialise it.
1742
self._transport.put_bytes_non_atomic(self._filename, '',
1743
mode=self._file_mode)
1745
def open_file(self):
1746
"""IFF this data access can be represented as a single file, open it.
1748
For knits that are not mapped to a single file on disk this will
1751
:return: None or a file handle.
1754
return self._transport.get(self._filename)
1759
def get_raw_records(self, memos_for_retrieval):
1760
"""Get the raw bytes for a records.
1762
:param memos_for_retrieval: An iterable containing the (index, pos,
1763
length) memo for retrieving the bytes. The .knit method ignores
1764
the index as there is always only a single file.
1765
:return: An iterator over the bytes of the records.
1767
read_vector = [(pos, size) for (index, pos, size) in memos_for_retrieval]
1768
for pos, data in self._transport.readv(self._filename, read_vector):
1772
class _PackAccess(object):
1773
"""Access to knit records via a collection of packs."""
1775
def __init__(self, index_to_packs, writer=None):
1776
"""Create a _PackAccess object.
1778
:param index_to_packs: A dict mapping index objects to the transport
1779
and file names for obtaining data.
1780
:param writer: A tuple (pack.ContainerWriter, write_index) which
1781
contains the pack to write, and the index that reads from it will
1785
self.container_writer = writer[0]
1786
self.write_index = writer[1]
1788
self.container_writer = None
1789
self.write_index = None
1790
self.indices = index_to_packs
1792
def add_raw_records(self, sizes, raw_data):
1793
"""Add raw knit bytes to a storage area.
1795
The data is spooled to the container writer in one bytes-record per
1798
:param sizes: An iterable containing the size of each raw data segment.
1799
:param raw_data: A bytestring containing the data.
1800
:return: A list of memos to retrieve the record later. Each memo is a
1801
tuple - (index, pos, length), where the index field is the
1802
write_index object supplied to the PackAccess object.
1804
assert type(raw_data) == str, \
1805
'data must be plain bytes was %s' % type(raw_data)
1809
p_offset, p_length = self.container_writer.add_bytes_record(
1810
raw_data[offset:offset+size], [])
1812
result.append((self.write_index, p_offset, p_length))
1816
"""Pack based knits do not get individually created."""
1818
def get_raw_records(self, memos_for_retrieval):
1819
"""Get the raw bytes for a records.
1821
:param memos_for_retrieval: An iterable containing the (index, pos,
1822
length) memo for retrieving the bytes. The Pack access method
1823
looks up the pack to use for a given record in its index_to_pack
1825
:return: An iterator over the bytes of the records.
1827
# first pass, group into same-index requests
1829
current_index = None
1830
for (index, offset, length) in memos_for_retrieval:
1831
if current_index == index:
1832
current_list.append((offset, length))
1834
if current_index is not None:
1835
request_lists.append((current_index, current_list))
1836
current_index = index
1837
current_list = [(offset, length)]
1838
# handle the last entry
1839
if current_index is not None:
1840
request_lists.append((current_index, current_list))
1841
for index, offsets in request_lists:
1842
transport, path = self.indices[index]
1843
reader = pack.make_readv_reader(transport, path, offsets)
1844
for names, read_func in reader.iter_records():
1845
yield read_func(None)
1847
def open_file(self):
1848
"""Pack based knits have no single file."""
1851
def set_writer(self, writer, index, (transport, packname)):
1852
"""Set a writer to use for adding data."""
1853
self.indices[index] = (transport, packname)
1854
self.container_writer = writer
1855
self.write_index = index
1858
class _KnitData(object):
1859
"""Manage extraction of data from a KnitAccess, caching and decompressing.
1861
The KnitData class provides the logic for parsing and using knit records,
1862
making use of an access method for the low level read and write operations.
1865
def __init__(self, access):
1866
"""Create a KnitData object.
1868
:param access: The access method to use. Access methods such as
1869
_KnitAccess manage the insertion of raw records and the subsequent
1870
retrieval of the same.
1872
self._access = access
1873
self._checked = False
1874
# TODO: jam 20060713 conceptually, this could spill to disk
1875
# if the cached size gets larger than a certain amount
1876
# but it complicates the model a bit, so for now just use
1877
# a simple dictionary
1879
self._do_cache = False
1881
def enable_cache(self):
1882
"""Enable caching of reads."""
1883
self._do_cache = True
1885
def clear_cache(self):
1886
"""Clear the record cache."""
1887
self._do_cache = False
1890
def _open_file(self):
1891
return self._access.open_file()
1893
def _record_to_data(self, version_id, digest, lines):
1894
"""Convert version_id, digest, lines into a raw data block.
1896
:return: (len, a StringIO instance with the raw data ready to read.)
1899
data_file = GzipFile(None, mode='wb', fileobj=sio)
1901
assert isinstance(version_id, str)
1902
data_file.writelines(chain(
1903
["version %s %d %s\n" % (version_id,
1907
["end %s\n" % version_id]))
1914
def add_raw_records(self, sizes, raw_data):
1915
"""Append a prepared record to the data file.
1917
:param sizes: An iterable containing the size of each raw data segment.
1918
:param raw_data: A bytestring containing the data.
1919
:return: a list of index data for the way the data was stored.
1920
See the access method add_raw_records documentation for more
1923
return self._access.add_raw_records(sizes, raw_data)
1925
def add_record(self, version_id, digest, lines):
1926
"""Write new text record to disk.
1928
Returns index data for retrieving it later, as per add_raw_records.
1930
size, sio = self._record_to_data(version_id, digest, lines)
1931
result = self.add_raw_records([size], sio.getvalue())
1933
self._cache[version_id] = sio.getvalue()
1936
def _parse_record_header(self, version_id, raw_data):
1937
"""Parse a record header for consistency.
1939
:return: the header and the decompressor stream.
1940
as (stream, header_record)
1942
df = GzipFile(mode='rb', fileobj=StringIO(raw_data))
1944
rec = self._check_header(version_id, df.readline())
1945
except Exception, e:
1946
raise KnitCorrupt(self._access,
1947
"While reading {%s} got %s(%s)"
1948
% (version_id, e.__class__.__name__, str(e)))
1951
def _check_header(self, version_id, line):
1954
raise KnitCorrupt(self._access,
1955
'unexpected number of elements in record header')
1956
if rec[1] != version_id:
1957
raise KnitCorrupt(self._access,
1958
'unexpected version, wanted %r, got %r'
1959
% (version_id, rec[1]))
1962
def _parse_record(self, version_id, data):
1964
# 4168 calls in 2880 217 internal
1965
# 4168 calls to _parse_record_header in 2121
1966
# 4168 calls to readlines in 330
1967
df = GzipFile(mode='rb', fileobj=StringIO(data))
1970
record_contents = df.readlines()
1971
except Exception, e:
1972
raise KnitCorrupt(self._access,
1973
"While reading {%s} got %s(%s)"
1974
% (version_id, e.__class__.__name__, str(e)))
1975
header = record_contents.pop(0)
1976
rec = self._check_header(version_id, header)
1978
last_line = record_contents.pop()
1979
if len(record_contents) != int(rec[2]):
1980
raise KnitCorrupt(self._access,
1981
'incorrect number of lines %s != %s'
1983
% (len(record_contents), int(rec[2]),
1985
if last_line != 'end %s\n' % rec[1]:
1986
raise KnitCorrupt(self._access,
1987
'unexpected version end line %r, wanted %r'
1988
% (last_line, version_id))
1990
return record_contents, rec[3]
1992
def read_records_iter_raw(self, records):
1993
"""Read text records from data file and yield raw data.
1995
This unpacks enough of the text record to validate the id is
1996
as expected but thats all.
1998
# setup an iterator of the external records:
1999
# uses readv so nice and fast we hope.
2001
# grab the disk data needed.
2003
# Don't check _cache if it is empty
2004
needed_offsets = [index_memo for version_id, index_memo
2006
if version_id not in self._cache]
2008
needed_offsets = [index_memo for version_id, index_memo
2011
raw_records = self._access.get_raw_records(needed_offsets)
2013
for version_id, index_memo in records:
2014
if version_id in self._cache:
2015
# This data has already been validated
2016
data = self._cache[version_id]
2018
data = raw_records.next()
2020
self._cache[version_id] = data
2022
# validate the header
2023
df, rec = self._parse_record_header(version_id, data)
2025
yield version_id, data
2027
def read_records_iter(self, records):
2028
"""Read text records from data file and yield result.
2030
The result will be returned in whatever is the fastest to read.
2031
Not by the order requested. Also, multiple requests for the same
2032
record will only yield 1 response.
2033
:param records: A list of (version_id, pos, len) entries
2034
:return: Yields (version_id, contents, digest) in the order
2035
read, not the order requested
2041
# Skip records we have alread seen
2042
yielded_records = set()
2043
needed_records = set()
2044
for record in records:
2045
if record[0] in self._cache:
2046
if record[0] in yielded_records:
2048
yielded_records.add(record[0])
2049
data = self._cache[record[0]]
2050
content, digest = self._parse_record(record[0], data)
2051
yield (record[0], content, digest)
2053
needed_records.add(record)
2054
needed_records = sorted(needed_records, key=operator.itemgetter(1))
2056
needed_records = sorted(set(records), key=operator.itemgetter(1))
2058
if not needed_records:
2061
# The transport optimizes the fetching as well
2062
# (ie, reads continuous ranges.)
2063
raw_data = self._access.get_raw_records(
2064
[index_memo for version_id, index_memo in needed_records])
2066
for (version_id, index_memo), data in \
2067
izip(iter(needed_records), raw_data):
2068
content, digest = self._parse_record(version_id, data)
2070
self._cache[version_id] = data
2071
yield version_id, content, digest
2073
def read_records(self, records):
2074
"""Read records into a dictionary."""
2076
for record_id, content, digest in \
2077
self.read_records_iter(records):
2078
components[record_id] = (content, digest)
2082
class InterKnit(InterVersionedFile):
2083
"""Optimised code paths for knit to knit operations."""
2085
_matching_file_from_factory = KnitVersionedFile
2086
_matching_file_to_factory = KnitVersionedFile
2089
def is_compatible(source, target):
2090
"""Be compatible with knits. """
2092
return (isinstance(source, KnitVersionedFile) and
2093
isinstance(target, KnitVersionedFile))
2094
except AttributeError:
2097
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
2098
"""See InterVersionedFile.join."""
2099
assert isinstance(self.source, KnitVersionedFile)
2100
assert isinstance(self.target, KnitVersionedFile)
2102
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
2107
pb = ui.ui_factory.nested_progress_bar()
2109
version_ids = list(version_ids)
2110
if None in version_ids:
2111
version_ids.remove(None)
2113
self.source_ancestry = set(self.source.get_ancestry(version_ids))
2114
this_versions = set(self.target._index.get_versions())
2115
needed_versions = self.source_ancestry - this_versions
2116
cross_check_versions = self.source_ancestry.intersection(this_versions)
2117
mismatched_versions = set()
2118
for version in cross_check_versions:
2119
# scan to include needed parents.
2120
n1 = set(self.target.get_parents_with_ghosts(version))
2121
n2 = set(self.source.get_parents_with_ghosts(version))
2123
# FIXME TEST this check for cycles being introduced works
2124
# the logic is we have a cycle if in our graph we are an
2125
# ancestor of any of the n2 revisions.
2131
parent_ancestors = self.source.get_ancestry(parent)
2132
if version in parent_ancestors:
2133
raise errors.GraphCycleError([parent, version])
2134
# ensure this parent will be available later.
2135
new_parents = n2.difference(n1)
2136
needed_versions.update(new_parents.difference(this_versions))
2137
mismatched_versions.add(version)
2139
if not needed_versions and not mismatched_versions:
2141
full_list = topo_sort(self.source.get_graph())
2143
version_list = [i for i in full_list if (not self.target.has_version(i)
2144
and i in needed_versions)]
2148
copy_queue_records = []
2150
for version_id in version_list:
2151
options = self.source._index.get_options(version_id)
2152
parents = self.source._index.get_parents_with_ghosts(version_id)
2153
# check that its will be a consistent copy:
2154
for parent in parents:
2155
# if source has the parent, we must :
2156
# * already have it or
2157
# * have it scheduled already
2158
# otherwise we don't care
2159
assert (self.target.has_version(parent) or
2160
parent in copy_set or
2161
not self.source.has_version(parent))
2162
index_memo = self.source._index.get_position(version_id)
2163
copy_queue_records.append((version_id, index_memo))
2164
copy_queue.append((version_id, options, parents))
2165
copy_set.add(version_id)
2167
# data suck the join:
2169
total = len(version_list)
2172
for (version_id, raw_data), \
2173
(version_id2, options, parents) in \
2174
izip(self.source._data.read_records_iter_raw(copy_queue_records),
2176
assert version_id == version_id2, 'logic error, inconsistent results'
2178
pb.update("Joining knit", count, total)
2179
raw_records.append((version_id, options, parents, len(raw_data)))
2180
raw_datum.append(raw_data)
2181
self.target._add_raw_records(raw_records, ''.join(raw_datum))
2183
for version in mismatched_versions:
2184
# FIXME RBC 20060309 is this needed?
2185
n1 = set(self.target.get_parents_with_ghosts(version))
2186
n2 = set(self.source.get_parents_with_ghosts(version))
2187
# write a combined record to our history preserving the current
2188
# parents as first in the list
2189
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
2190
self.target.fix_parents(version, new_parents)
2196
InterVersionedFile.register_optimiser(InterKnit)
2199
class WeaveToKnit(InterVersionedFile):
2200
"""Optimised code paths for weave to knit operations."""
2202
_matching_file_from_factory = bzrlib.weave.WeaveFile
2203
_matching_file_to_factory = KnitVersionedFile
2206
def is_compatible(source, target):
2207
"""Be compatible with weaves to knits."""
2209
return (isinstance(source, bzrlib.weave.Weave) and
2210
isinstance(target, KnitVersionedFile))
2211
except AttributeError:
2214
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
2215
"""See InterVersionedFile.join."""
2216
assert isinstance(self.source, bzrlib.weave.Weave)
2217
assert isinstance(self.target, KnitVersionedFile)
2219
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
2224
pb = ui.ui_factory.nested_progress_bar()
2226
version_ids = list(version_ids)
2228
self.source_ancestry = set(self.source.get_ancestry(version_ids))
2229
this_versions = set(self.target._index.get_versions())
2230
needed_versions = self.source_ancestry - this_versions
2231
cross_check_versions = self.source_ancestry.intersection(this_versions)
2232
mismatched_versions = set()
2233
for version in cross_check_versions:
2234
# scan to include needed parents.
2235
n1 = set(self.target.get_parents_with_ghosts(version))
2236
n2 = set(self.source.get_parents(version))
2237
# if all of n2's parents are in n1, then its fine.
2238
if n2.difference(n1):
2239
# FIXME TEST this check for cycles being introduced works
2240
# the logic is we have a cycle if in our graph we are an
2241
# ancestor of any of the n2 revisions.
2247
parent_ancestors = self.source.get_ancestry(parent)
2248
if version in parent_ancestors:
2249
raise errors.GraphCycleError([parent, version])
2250
# ensure this parent will be available later.
2251
new_parents = n2.difference(n1)
2252
needed_versions.update(new_parents.difference(this_versions))
2253
mismatched_versions.add(version)
2255
if not needed_versions and not mismatched_versions:
2257
full_list = topo_sort(self.source.get_graph())
2259
version_list = [i for i in full_list if (not self.target.has_version(i)
2260
and i in needed_versions)]
2264
total = len(version_list)
2265
for version_id in version_list:
2266
pb.update("Converting to knit", count, total)
2267
parents = self.source.get_parents(version_id)
2268
# check that its will be a consistent copy:
2269
for parent in parents:
2270
# if source has the parent, we must already have it
2271
assert (self.target.has_version(parent))
2272
self.target.add_lines(
2273
version_id, parents, self.source.get_lines(version_id))
2276
for version in mismatched_versions:
2277
# FIXME RBC 20060309 is this needed?
2278
n1 = set(self.target.get_parents_with_ghosts(version))
2279
n2 = set(self.source.get_parents(version))
2280
# write a combined record to our history preserving the current
2281
# parents as first in the list
2282
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
2283
self.target.fix_parents(version, new_parents)
2289
InterVersionedFile.register_optimiser(WeaveToKnit)
2292
class KnitSequenceMatcher(difflib.SequenceMatcher):
2293
"""Knit tuned sequence matcher.
2295
This is based on profiling of difflib which indicated some improvements
2296
for our usage pattern.
2299
def find_longest_match(self, alo, ahi, blo, bhi):
2300
"""Find longest matching block in a[alo:ahi] and b[blo:bhi].
2302
If isjunk is not defined:
2304
Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
2305
alo <= i <= i+k <= ahi
2306
blo <= j <= j+k <= bhi
2307
and for all (i',j',k') meeting those conditions,
2310
and if i == i', j <= j'
2312
In other words, of all maximal matching blocks, return one that
2313
starts earliest in a, and of all those maximal matching blocks that
2314
start earliest in a, return the one that starts earliest in b.
2316
>>> s = SequenceMatcher(None, " abcd", "abcd abcd")
2317
>>> s.find_longest_match(0, 5, 0, 9)
2320
If isjunk is defined, first the longest matching block is
2321
determined as above, but with the additional restriction that no
2322
junk element appears in the block. Then that block is extended as
2323
far as possible by matching (only) junk elements on both sides. So
2324
the resulting block never matches on junk except as identical junk
2325
happens to be adjacent to an "interesting" match.
2327
Here's the same example as before, but considering blanks to be
2328
junk. That prevents " abcd" from matching the " abcd" at the tail
2329
end of the second sequence directly. Instead only the "abcd" can
2330
match, and matches the leftmost "abcd" in the second sequence:
2332
>>> s = SequenceMatcher(lambda x: x==" ", " abcd", "abcd abcd")
2333
>>> s.find_longest_match(0, 5, 0, 9)
2336
If no blocks match, return (alo, blo, 0).
2338
>>> s = SequenceMatcher(None, "ab", "c")
2339
>>> s.find_longest_match(0, 2, 0, 1)
2343
# CAUTION: stripping common prefix or suffix would be incorrect.
2347
# Longest matching block is "ab", but if common prefix is
2348
# stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
2349
# strip, so ends up claiming that ab is changed to acab by
2350
# inserting "ca" in the middle. That's minimal but unintuitive:
2351
# "it's obvious" that someone inserted "ac" at the front.
2352
# Windiff ends up at the same place as diff, but by pairing up
2353
# the unique 'b's and then matching the first two 'a's.
2355
a, b, b2j, isbjunk = self.a, self.b, self.b2j, self.isbjunk
2356
besti, bestj, bestsize = alo, blo, 0
2357
# find longest junk-free match
2358
# during an iteration of the loop, j2len[j] = length of longest
2359
# junk-free match ending with a[i-1] and b[j]
2363
for i in xrange(alo, ahi):
2364
# look at all instances of a[i] in b; note that because
2365
# b2j has no junk keys, the loop is skipped if a[i] is junk
2366
j2lenget = j2len.get
2369
# changing b2j.get(a[i], nothing) to a try:KeyError pair produced the
2370
# following improvement
2371
# 704 0 4650.5320 2620.7410 bzrlib.knit:1336(find_longest_match)
2372
# +326674 0 1655.1210 1655.1210 +<method 'get' of 'dict' objects>
2373
# +76519 0 374.6700 374.6700 +<method 'has_key' of 'dict' objects>
2375
# 704 0 3733.2820 2209.6520 bzrlib.knit:1336(find_longest_match)
2376
# +211400 0 1147.3520 1147.3520 +<method 'get' of 'dict' objects>
2377
# +76519 0 376.2780 376.2780 +<method 'has_key' of 'dict' objects>
2389
k = newj2len[j] = 1 + j2lenget(-1 + j, 0)
2391
besti, bestj, bestsize = 1 + i-k, 1 + j-k, k
2394
# Extend the best by non-junk elements on each end. In particular,
2395
# "popular" non-junk elements aren't in b2j, which greatly speeds
2396
# the inner loop above, but also means "the best" match so far
2397
# doesn't contain any junk *or* popular non-junk elements.
2398
while besti > alo and bestj > blo and \
2399
not isbjunk(b[bestj-1]) and \
2400
a[besti-1] == b[bestj-1]:
2401
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
2402
while besti+bestsize < ahi and bestj+bestsize < bhi and \
2403
not isbjunk(b[bestj+bestsize]) and \
2404
a[besti+bestsize] == b[bestj+bestsize]:
2407
# Now that we have a wholly interesting match (albeit possibly
2408
# empty!), we may as well suck up the matching junk on each
2409
# side of it too. Can't think of a good reason not to, and it
2410
# saves post-processing the (possibly considerable) expense of
2411
# figuring out what to do with it. In the case of an empty
2412
# interesting match, this is clearly the right thing to do,
2413
# because no other kind of match is possible in the regions.
2414
while besti > alo and bestj > blo and \
2415
isbjunk(b[bestj-1]) and \
2416
a[besti-1] == b[bestj-1]:
2417
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
2418
while besti+bestsize < ahi and bestj+bestsize < bhi and \
2419
isbjunk(b[bestj+bestsize]) and \
2420
a[besti+bestsize] == b[bestj+bestsize]:
2421
bestsize = bestsize + 1
2423
return besti, bestj, bestsize
2427
from bzrlib._knit_load_data_c import _load_data_c as _load_data
2429
from bzrlib._knit_load_data_py import _load_data_py as _load_data
added
removed
bzrlib/knit.py
