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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 zlib import Z_DEFAULT_COMPRESSION
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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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KnitDataStreamIncompatible,
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RevisionAlreadyPresent,
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from bzrlib.tuned_gzip import GzipFile
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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 get_data_stream(self, required_versions):
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"""Get a data stream for the specified versions.
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Versions may be returned in any order, not necessarily the order
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:param required_versions: The exact set of versions to be extracted.
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Unlike some other knit methods, this is not used to generate a
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transitive closure, rather it is used precisely as given.
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:returns: format_signature, list of (version, options, length, parents),
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required_versions = set([osutils.safe_revision_id(v) for v in
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# we don't care about inclusions, the caller cares.
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# but we need to setup a list of records to visit.
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for version_id in required_versions:
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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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# Pick the desired versions out of the index in oldest-to-newest order
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for version_id in self.versions():
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if version_id in required_versions:
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version_list.append(version_id)
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# create the list of version information for the result
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copy_queue_records = []
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result_version_list = []
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for version_id in version_list:
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options = self._index.get_options(version_id)
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parents = self._index.get_parents_with_ghosts(version_id)
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index_memo = self._index.get_position(version_id)
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copy_queue_records.append((version_id, index_memo))
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none, data_pos, data_size = index_memo
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copy_set.add(version_id)
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# version, options, length, parents
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result_version_list.append((version_id, options, data_size,
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# Read the compressed record data.
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# From here down to the return should really be logic in the returned
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# callable -- in a class that adapts read_records_iter_raw to read
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for (version_id, raw_data), \
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(version_id2, options, _, parents) in \
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izip(self._data.read_records_iter_raw(copy_queue_records),
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result_version_list):
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assert version_id == version_id2, 'logic error, inconsistent results'
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raw_datum.append(raw_data)
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pseudo_file = StringIO(''.join(raw_datum))
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return pseudo_file.read()
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return pseudo_file.read(length)
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return (self.get_format_signature(), result_version_list, read)
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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_format_signature(self):
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"""See VersionedFile.get_format_signature()."""
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if self.factory.annotated:
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annotated_part = "annotated"
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annotated_part = "plain"
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return "knit-%s" % (annotated_part,)
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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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def insert_data_stream(self, (format, data_list, reader_callable)):
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"""Insert knit records from a data stream into this knit.
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If a version in the stream is already present in this knit, it will not
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be inserted a second time. It will be checked for consistency with the
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stored version however, and may cause a KnitCorrupt error to be raised
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if the data in the stream disagrees with the already stored data.
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:seealso: get_data_stream
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if format != self.get_format_signature():
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trace.mutter('incompatible format signature inserting to %r', self)
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raise KnitDataStreamIncompatible(
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format, self.get_format_signature())
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for version_id, options, length, parents in data_list:
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if self.has_version(version_id):
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# First check: the list of parents.
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my_parents = self.get_parents_with_ghosts(version_id)
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if my_parents != parents:
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# XXX: KnitCorrupt is not quite the right exception here.
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'parents list %r from data stream does not match '
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'already recorded parents %r for %s'
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% (parents, my_parents, version_id))
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# Also check the SHA-1 of the fulltext this content will
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raw_data = reader_callable(length)
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my_fulltext_sha1 = self.get_sha1(version_id)
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df, rec = self._data._parse_record_header(version_id, raw_data)
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stream_fulltext_sha1 = rec[3]
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if my_fulltext_sha1 != stream_fulltext_sha1:
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# Actually, we don't know if it's this knit that's corrupt,
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# or the data stream we're trying to insert.
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self.filename, 'sha-1 does not match %s' % version_id)
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self._add_raw_records(
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[(version_id, options, parents, length)],
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reader_callable(length))
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"""See VersionedFile.versions."""
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if 'evil' in debug.debug_flags:
751
trace.mutter_callsite(2, "versions scales with size of history")
752
return self._index.get_versions()
754
def has_version(self, version_id):
755
"""See VersionedFile.has_version."""
756
if 'evil' in debug.debug_flags:
757
trace.mutter_callsite(2, "has_version is a LBYL scenario")
758
version_id = osutils.safe_revision_id(version_id)
759
return self._index.has_version(version_id)
761
__contains__ = has_version
763
def _merge_annotations(self, content, parents, parent_texts={},
764
delta=None, annotated=None,
765
left_matching_blocks=None):
766
"""Merge annotations for content. This is done by comparing
767
the annotations based on changed to the text.
769
if left_matching_blocks is not None:
770
delta_seq = diff._PrematchedMatcher(left_matching_blocks)
774
for parent_id in parents:
775
merge_content = self._get_content(parent_id, parent_texts)
776
if (parent_id == parents[0] and delta_seq is not None):
779
seq = patiencediff.PatienceSequenceMatcher(
780
None, merge_content.text(), content.text())
781
for i, j, n in seq.get_matching_blocks():
784
# this appears to copy (origin, text) pairs across to the
785
# new content for any line that matches the last-checked
787
content._lines[j:j+n] = merge_content._lines[i:i+n]
789
if delta_seq is None:
790
reference_content = self._get_content(parents[0], parent_texts)
791
new_texts = content.text()
792
old_texts = reference_content.text()
793
delta_seq = patiencediff.PatienceSequenceMatcher(
794
None, old_texts, new_texts)
795
return self._make_line_delta(delta_seq, content)
797
def _make_line_delta(self, delta_seq, new_content):
798
"""Generate a line delta from delta_seq and new_content."""
800
for op in delta_seq.get_opcodes():
803
diff_hunks.append((op[1], op[2], op[4]-op[3], new_content._lines[op[3]:op[4]]))
806
def _get_components_positions(self, version_ids):
807
"""Produce a map of position data for the components of versions.
809
This data is intended to be used for retrieving the knit records.
811
A dict of version_id to (method, data_pos, data_size, next) is
813
method is the way referenced data should be applied.
814
data_pos is the position of the data in the knit.
815
data_size is the size of the data in the knit.
816
next is the build-parent of the version, or None for fulltexts.
819
for version_id in version_ids:
822
while cursor is not None and cursor not in component_data:
823
method = self._index.get_method(cursor)
824
if method == 'fulltext':
827
next = self.get_parents(cursor)[0]
828
index_memo = self._index.get_position(cursor)
829
component_data[cursor] = (method, index_memo, next)
831
return component_data
833
def _get_content(self, version_id, parent_texts={}):
834
"""Returns a content object that makes up the specified
836
if not self.has_version(version_id):
837
raise RevisionNotPresent(version_id, self.filename)
839
cached_version = parent_texts.get(version_id, None)
840
if cached_version is not None:
841
return cached_version
843
text_map, contents_map = self._get_content_maps([version_id])
844
return contents_map[version_id]
846
def _check_versions_present(self, version_ids):
847
"""Check that all specified versions are present."""
848
self._index.check_versions_present(version_ids)
850
def _add_lines_with_ghosts(self, version_id, parents, lines, parent_texts):
851
"""See VersionedFile.add_lines_with_ghosts()."""
852
self._check_add(version_id, lines)
853
return self._add(version_id, lines[:], parents, self.delta, parent_texts)
855
def _add_lines(self, version_id, parents, lines, parent_texts,
856
left_matching_blocks=None):
857
"""See VersionedFile.add_lines."""
858
self._check_add(version_id, lines)
859
self._check_versions_present(parents)
860
return self._add(version_id, lines[:], parents, self.delta,
861
parent_texts, left_matching_blocks)
863
def _check_add(self, version_id, lines):
864
"""check that version_id and lines are safe to add."""
865
assert self.writable, "knit is not opened for write"
866
### FIXME escape. RBC 20060228
867
if contains_whitespace(version_id):
868
raise InvalidRevisionId(version_id, self.filename)
869
self.check_not_reserved_id(version_id)
870
if self.has_version(version_id):
871
raise RevisionAlreadyPresent(version_id, self.filename)
872
self._check_lines_not_unicode(lines)
873
self._check_lines_are_lines(lines)
875
def _add(self, version_id, lines, parents, delta, parent_texts,
876
left_matching_blocks=None):
877
"""Add a set of lines on top of version specified by parents.
879
If delta is true, compress the text as a line-delta against
882
Any versions not present will be converted into ghosts.
884
# 461 0 6546.0390 43.9100 bzrlib.knit:489(_add)
885
# +400 0 889.4890 418.9790 +bzrlib.knit:192(lower_fulltext)
886
# +461 0 1364.8070 108.8030 +bzrlib.knit:996(add_record)
887
# +461 0 193.3940 41.5720 +bzrlib.knit:898(add_version)
888
# +461 0 134.0590 18.3810 +bzrlib.osutils:361(sha_strings)
889
# +461 0 36.3420 15.4540 +bzrlib.knit:146(make)
890
# +1383 0 8.0370 8.0370 +<len>
891
# +61 0 13.5770 7.9190 +bzrlib.knit:199(lower_line_delta)
892
# +61 0 963.3470 7.8740 +bzrlib.knit:427(_get_content)
893
# +61 0 973.9950 5.2950 +bzrlib.knit:136(line_delta)
894
# +61 0 1918.1800 5.2640 +bzrlib.knit:359(_merge_annotations)
898
if parent_texts is None:
900
for parent in parents:
901
if not self.has_version(parent):
902
ghosts.append(parent)
904
present_parents.append(parent)
906
if delta and not len(present_parents):
909
digest = sha_strings(lines)
910
text_length = sum(map(len, lines))
913
if lines[-1][-1] != '\n':
914
options.append('no-eol')
915
lines[-1] = lines[-1] + '\n'
917
if len(present_parents) and delta:
918
# To speed the extract of texts the delta chain is limited
919
# to a fixed number of deltas. This should minimize both
920
# I/O and the time spend applying deltas.
921
delta = self._check_should_delta(present_parents)
923
assert isinstance(version_id, str)
924
lines = self.factory.make(lines, version_id)
925
if delta or (self.factory.annotated and len(present_parents) > 0):
926
# Merge annotations from parent texts if so is needed.
927
delta_hunks = self._merge_annotations(lines, present_parents,
928
parent_texts, delta, self.factory.annotated,
929
left_matching_blocks)
932
options.append('line-delta')
933
store_lines = self.factory.lower_line_delta(delta_hunks)
935
options.append('fulltext')
936
store_lines = self.factory.lower_fulltext(lines)
938
access_memo = self._data.add_record(version_id, digest, store_lines)
939
self._index.add_version(version_id, options, access_memo, parents)
940
return digest, text_length, lines
942
def check(self, progress_bar=None):
943
"""See VersionedFile.check()."""
945
def _clone_text(self, new_version_id, old_version_id, parents):
946
"""See VersionedFile.clone_text()."""
947
# FIXME RBC 20060228 make fast by only inserting an index with null
949
self.add_lines(new_version_id, parents, self.get_lines(old_version_id))
951
def get_lines(self, version_id):
952
"""See VersionedFile.get_lines()."""
953
return self.get_line_list([version_id])[0]
955
def _get_record_map(self, version_ids):
956
"""Produce a dictionary of knit records.
958
The keys are version_ids, the values are tuples of (method, content,
960
method is the way the content should be applied.
961
content is a KnitContent object.
962
digest is the SHA1 digest of this version id after all steps are done
963
next is the build-parent of the version, i.e. the leftmost ancestor.
964
If the method is fulltext, next will be None.
966
position_map = self._get_components_positions(version_ids)
967
# c = component_id, m = method, i_m = index_memo, n = next
968
records = [(c, i_m) for c, (m, i_m, n) in position_map.iteritems()]
970
for component_id, content, digest in \
971
self._data.read_records_iter(records):
972
method, index_memo, next = position_map[component_id]
973
record_map[component_id] = method, content, digest, next
977
def get_text(self, version_id):
978
"""See VersionedFile.get_text"""
979
return self.get_texts([version_id])[0]
981
def get_texts(self, version_ids):
982
return [''.join(l) for l in self.get_line_list(version_ids)]
984
def get_line_list(self, version_ids):
985
"""Return the texts of listed versions as a list of strings."""
986
version_ids = [osutils.safe_revision_id(v) for v in version_ids]
987
for version_id in version_ids:
988
self.check_not_reserved_id(version_id)
989
text_map, content_map = self._get_content_maps(version_ids)
990
return [text_map[v] for v in version_ids]
992
_get_lf_split_line_list = get_line_list
994
def _get_content_maps(self, version_ids):
995
"""Produce maps of text and KnitContents
997
:return: (text_map, content_map) where text_map contains the texts for
998
the requested versions and content_map contains the KnitContents.
999
Both dicts take version_ids as their keys.
1001
for version_id in version_ids:
1002
if not self.has_version(version_id):
1003
raise RevisionNotPresent(version_id, self.filename)
1004
record_map = self._get_record_map(version_ids)
1009
for version_id in version_ids:
1012
while cursor is not None:
1013
method, data, digest, next = record_map[cursor]
1014
components.append((cursor, method, data, digest))
1015
if cursor in content_map:
1020
for component_id, method, data, digest in reversed(components):
1021
if component_id in content_map:
1022
content = content_map[component_id]
1024
if method == 'fulltext':
1025
assert content is None
1026
content = self.factory.parse_fulltext(data, version_id)
1027
elif method == 'line-delta':
1028
delta = self.factory.parse_line_delta(data, version_id)
1029
content = content.copy()
1030
content._lines = self._apply_delta(content._lines,
1032
content_map[component_id] = content
1034
if 'no-eol' in self._index.get_options(version_id):
1035
content = content.copy()
1036
line = content._lines[-1][1].rstrip('\n')
1037
content._lines[-1] = (content._lines[-1][0], line)
1038
final_content[version_id] = content
1040
# digest here is the digest from the last applied component.
1041
text = content.text()
1042
if sha_strings(text) != digest:
1043
raise KnitCorrupt(self.filename,
1044
'sha-1 does not match %s' % version_id)
1046
text_map[version_id] = text
1047
return text_map, final_content
1049
def iter_lines_added_or_present_in_versions(self, version_ids=None,
1051
"""See VersionedFile.iter_lines_added_or_present_in_versions()."""
1052
if version_ids is None:
1053
version_ids = self.versions()
1055
version_ids = [osutils.safe_revision_id(v) for v in version_ids]
1057
pb = progress.DummyProgress()
1058
# we don't care about inclusions, the caller cares.
1059
# but we need to setup a list of records to visit.
1060
# we need version_id, position, length
1061
version_id_records = []
1062
requested_versions = set(version_ids)
1063
# filter for available versions
1064
for version_id in requested_versions:
1065
if not self.has_version(version_id):
1066
raise RevisionNotPresent(version_id, self.filename)
1067
# get a in-component-order queue:
1068
for version_id in self.versions():
1069
if version_id in requested_versions:
1070
index_memo = self._index.get_position(version_id)
1071
version_id_records.append((version_id, index_memo))
1073
total = len(version_id_records)
1074
for version_idx, (version_id, data, sha_value) in \
1075
enumerate(self._data.read_records_iter(version_id_records)):
1076
pb.update('Walking content.', version_idx, total)
1077
method = self._index.get_method(version_id)
1079
assert method in ('fulltext', 'line-delta')
1080
if method == 'fulltext':
1081
line_iterator = self.factory.get_fulltext_content(data)
1083
line_iterator = self.factory.get_linedelta_content(data)
1084
for line in line_iterator:
1087
pb.update('Walking content.', total, total)
1089
def iter_parents(self, version_ids):
1090
"""Iterate through the parents for many version ids.
1092
:param version_ids: An iterable yielding version_ids.
1093
:return: An iterator that yields (version_id, parents). Requested
1094
version_ids not present in the versioned file are simply skipped.
1095
The order is undefined, allowing for different optimisations in
1096
the underlying implementation.
1098
version_ids = [osutils.safe_revision_id(version_id) for
1099
version_id in version_ids]
1100
return self._index.iter_parents(version_ids)
1102
def num_versions(self):
1103
"""See VersionedFile.num_versions()."""
1104
return self._index.num_versions()
1106
__len__ = num_versions
1108
def annotate_iter(self, version_id):
1109
"""See VersionedFile.annotate_iter."""
1110
version_id = osutils.safe_revision_id(version_id)
1111
content = self._get_content(version_id)
1112
for origin, text in content.annotate_iter():
1115
def get_parents(self, version_id):
1116
"""See VersionedFile.get_parents."""
1119
# 52554 calls in 1264 872 internal down from 3674
1120
version_id = osutils.safe_revision_id(version_id)
1122
return self._index.get_parents(version_id)
1124
raise RevisionNotPresent(version_id, self.filename)
1126
def get_parents_with_ghosts(self, version_id):
1127
"""See VersionedFile.get_parents."""
1128
version_id = osutils.safe_revision_id(version_id)
1130
return self._index.get_parents_with_ghosts(version_id)
1132
raise RevisionNotPresent(version_id, self.filename)
1134
def get_ancestry(self, versions, topo_sorted=True):
1135
"""See VersionedFile.get_ancestry."""
1136
if isinstance(versions, basestring):
1137
versions = [versions]
1140
versions = [osutils.safe_revision_id(v) for v in versions]
1141
return self._index.get_ancestry(versions, topo_sorted)
1143
def get_ancestry_with_ghosts(self, versions):
1144
"""See VersionedFile.get_ancestry_with_ghosts."""
1145
if isinstance(versions, basestring):
1146
versions = [versions]
1149
versions = [osutils.safe_revision_id(v) for v in versions]
1150
return self._index.get_ancestry_with_ghosts(versions)
1152
def plan_merge(self, ver_a, ver_b):
1153
"""See VersionedFile.plan_merge."""
1154
ver_a = osutils.safe_revision_id(ver_a)
1155
ver_b = osutils.safe_revision_id(ver_b)
1156
ancestors_b = set(self.get_ancestry(ver_b, topo_sorted=False))
1158
ancestors_a = set(self.get_ancestry(ver_a, topo_sorted=False))
1159
annotated_a = self.annotate(ver_a)
1160
annotated_b = self.annotate(ver_b)
1161
return merge._plan_annotate_merge(annotated_a, annotated_b,
1162
ancestors_a, ancestors_b)
1165
class _KnitComponentFile(object):
1166
"""One of the files used to implement a knit database"""
1168
def __init__(self, transport, filename, mode, file_mode=None,
1169
create_parent_dir=False, dir_mode=None):
1170
self._transport = transport
1171
self._filename = filename
1173
self._file_mode = file_mode
1174
self._dir_mode = dir_mode
1175
self._create_parent_dir = create_parent_dir
1176
self._need_to_create = False
1178
def _full_path(self):
1179
"""Return the full path to this file."""
1180
return self._transport.base + self._filename
1182
def check_header(self, fp):
1183
line = fp.readline()
1185
# An empty file can actually be treated as though the file doesn't
1187
raise errors.NoSuchFile(self._full_path())
1188
if line != self.HEADER:
1189
raise KnitHeaderError(badline=line,
1190
filename=self._transport.abspath(self._filename))
1193
return '%s(%s)' % (self.__class__.__name__, self._filename)
1196
class _KnitIndex(_KnitComponentFile):
1197
"""Manages knit index file.
1199
The index is already kept in memory and read on startup, to enable
1200
fast lookups of revision information. The cursor of the index
1201
file is always pointing to the end, making it easy to append
1204
_cache is a cache for fast mapping from version id to a Index
1207
_history is a cache for fast mapping from indexes to version ids.
1209
The index data format is dictionary compressed when it comes to
1210
parent references; a index entry may only have parents that with a
1211
lover index number. As a result, the index is topological sorted.
1213
Duplicate entries may be written to the index for a single version id
1214
if this is done then the latter one completely replaces the former:
1215
this allows updates to correct version and parent information.
1216
Note that the two entries may share the delta, and that successive
1217
annotations and references MUST point to the first entry.
1219
The index file on disc contains a header, followed by one line per knit
1220
record. The same revision can be present in an index file more than once.
1221
The first occurrence gets assigned a sequence number starting from 0.
1223
The format of a single line is
1224
REVISION_ID FLAGS BYTE_OFFSET LENGTH( PARENT_ID|PARENT_SEQUENCE_ID)* :\n
1225
REVISION_ID is a utf8-encoded revision id
1226
FLAGS is a comma separated list of flags about the record. Values include
1227
no-eol, line-delta, fulltext.
1228
BYTE_OFFSET is the ascii representation of the byte offset in the data file
1229
that the the compressed data starts at.
1230
LENGTH is the ascii representation of the length of the data file.
1231
PARENT_ID a utf-8 revision id prefixed by a '.' that is a parent of
1233
PARENT_SEQUENCE_ID the ascii representation of the sequence number of a
1234
revision id already in the knit that is a parent of REVISION_ID.
1235
The ' :' marker is the end of record marker.
1238
when a write is interrupted to the index file, it will result in a line
1239
that does not end in ' :'. If the ' :' is not present at the end of a line,
1240
or at the end of the file, then the record that is missing it will be
1241
ignored by the parser.
1243
When writing new records to the index file, the data is preceded by '\n'
1244
to ensure that records always start on new lines even if the last write was
1245
interrupted. As a result its normal for the last line in the index to be
1246
missing a trailing newline. One can be added with no harmful effects.
1249
HEADER = "# bzr knit index 8\n"
1251
# speed of knit parsing went from 280 ms to 280 ms with slots addition.
1252
# __slots__ = ['_cache', '_history', '_transport', '_filename']
1254
def _cache_version(self, version_id, options, pos, size, parents):
1255
"""Cache a version record in the history array and index cache.
1257
This is inlined into _load_data for performance. KEEP IN SYNC.
1258
(It saves 60ms, 25% of the __init__ overhead on local 4000 record
1261
# only want the _history index to reference the 1st index entry
1263
if version_id not in self._cache:
1264
index = len(self._history)
1265
self._history.append(version_id)
1267
index = self._cache[version_id][5]
1268
self._cache[version_id] = (version_id,
1275
def __init__(self, transport, filename, mode, create=False, file_mode=None,
1276
create_parent_dir=False, delay_create=False, dir_mode=None):
1277
_KnitComponentFile.__init__(self, transport, filename, mode,
1278
file_mode=file_mode,
1279
create_parent_dir=create_parent_dir,
1282
# position in _history is the 'official' index for a revision
1283
# but the values may have come from a newer entry.
1284
# so - wc -l of a knit index is != the number of unique names
1288
fp = self._transport.get(self._filename)
1290
# _load_data may raise NoSuchFile if the target knit is
1292
_load_data(self, fp)
1296
if mode != 'w' or not create:
1299
self._need_to_create = True
1301
self._transport.put_bytes_non_atomic(
1302
self._filename, self.HEADER, mode=self._file_mode)
1304
def get_graph(self):
1305
"""Return a list of the node:parents lists from this knit index."""
1306
return [(vid, idx[4]) for vid, idx in self._cache.iteritems()]
1308
def get_ancestry(self, versions, topo_sorted=True):
1309
"""See VersionedFile.get_ancestry."""
1310
# get a graph of all the mentioned versions:
1312
pending = set(versions)
1315
version = pending.pop()
1318
parents = [p for p in cache[version][4] if p in cache]
1320
raise RevisionNotPresent(version, self._filename)
1321
# if not completed and not a ghost
1322
pending.update([p for p in parents if p not in graph])
1323
graph[version] = parents
1326
return topo_sort(graph.items())
1328
def get_ancestry_with_ghosts(self, versions):
1329
"""See VersionedFile.get_ancestry_with_ghosts."""
1330
# get a graph of all the mentioned versions:
1331
self.check_versions_present(versions)
1334
pending = set(versions)
1336
version = pending.pop()
1338
parents = cache[version][4]
1344
pending.update([p for p in parents if p not in graph])
1345
graph[version] = parents
1346
return topo_sort(graph.items())
1348
def iter_parents(self, version_ids):
1349
"""Iterate through the parents for many version ids.
1351
:param version_ids: An iterable yielding version_ids.
1352
:return: An iterator that yields (version_id, parents). Requested
1353
version_ids not present in the versioned file are simply skipped.
1354
The order is undefined, allowing for different optimisations in
1355
the underlying implementation.
1357
for version_id in version_ids:
1359
yield version_id, tuple(self.get_parents(version_id))
1363
def num_versions(self):
1364
return len(self._history)
1366
__len__ = num_versions
1368
def get_versions(self):
1369
"""Get all the versions in the file. not topologically sorted."""
1370
return self._history
1372
def _version_list_to_index(self, versions):
1375
for version in versions:
1376
if version in cache:
1377
# -- inlined lookup() --
1378
result_list.append(str(cache[version][5]))
1379
# -- end lookup () --
1381
result_list.append('.' + version)
1382
return ' '.join(result_list)
1384
def add_version(self, version_id, options, index_memo, parents):
1385
"""Add a version record to the index."""
1386
self.add_versions(((version_id, options, index_memo, parents),))
1388
def add_versions(self, versions):
1389
"""Add multiple versions to the index.
1391
:param versions: a list of tuples:
1392
(version_id, options, pos, size, parents).
1395
orig_history = self._history[:]
1396
orig_cache = self._cache.copy()
1399
for version_id, options, (index, pos, size), parents in versions:
1400
line = "\n%s %s %s %s %s :" % (version_id,
1404
self._version_list_to_index(parents))
1405
assert isinstance(line, str), \
1406
'content must be utf-8 encoded: %r' % (line,)
1408
self._cache_version(version_id, options, pos, size, parents)
1409
if not self._need_to_create:
1410
self._transport.append_bytes(self._filename, ''.join(lines))
1413
sio.write(self.HEADER)
1414
sio.writelines(lines)
1416
self._transport.put_file_non_atomic(self._filename, sio,
1417
create_parent_dir=self._create_parent_dir,
1418
mode=self._file_mode,
1419
dir_mode=self._dir_mode)
1420
self._need_to_create = False
1422
# If any problems happen, restore the original values and re-raise
1423
self._history = orig_history
1424
self._cache = orig_cache
1427
def has_version(self, version_id):
1428
"""True if the version is in the index."""
1429
return version_id in self._cache
1431
def get_position(self, version_id):
1432
"""Return details needed to access the version.
1434
.kndx indices do not support split-out data, so return None for the
1437
:return: a tuple (None, data position, size) to hand to the access
1438
logic to get the record.
1440
entry = self._cache[version_id]
1441
return None, entry[2], entry[3]
1443
def get_method(self, version_id):
1444
"""Return compression method of specified version."""
1445
options = self._cache[version_id][1]
1446
if 'fulltext' in options:
1449
if 'line-delta' not in options:
1450
raise errors.KnitIndexUnknownMethod(self._full_path(), options)
1453
def get_options(self, version_id):
1454
"""Return a string represention options.
1458
return self._cache[version_id][1]
1460
def get_parents(self, version_id):
1461
"""Return parents of specified version ignoring ghosts."""
1462
return [parent for parent in self._cache[version_id][4]
1463
if parent in self._cache]
1465
def get_parents_with_ghosts(self, version_id):
1466
"""Return parents of specified version with ghosts."""
1467
return self._cache[version_id][4]
1469
def check_versions_present(self, version_ids):
1470
"""Check that all specified versions are present."""
1472
for version_id in version_ids:
1473
if version_id not in cache:
1474
raise RevisionNotPresent(version_id, self._filename)
1477
class KnitGraphIndex(object):
1478
"""A knit index that builds on GraphIndex."""
1480
def __init__(self, graph_index, deltas=False, parents=True, add_callback=None):
1481
"""Construct a KnitGraphIndex on a graph_index.
1483
:param graph_index: An implementation of bzrlib.index.GraphIndex.
1484
:param deltas: Allow delta-compressed records.
1485
:param add_callback: If not None, allow additions to the index and call
1486
this callback with a list of added GraphIndex nodes:
1487
[(node, value, node_refs), ...]
1488
:param parents: If True, record knits parents, if not do not record
1491
self._graph_index = graph_index
1492
self._deltas = deltas
1493
self._add_callback = add_callback
1494
self._parents = parents
1495
if deltas and not parents:
1496
raise KnitCorrupt(self, "Cannot do delta compression without "
1499
def _get_entries(self, keys, check_present=False):
1500
"""Get the entries for keys.
1502
:param keys: An iterable of index keys, - 1-tuples.
1507
for node in self._graph_index.iter_entries(keys):
1509
found_keys.add(node[1])
1511
# adapt parentless index to the rest of the code.
1512
for node in self._graph_index.iter_entries(keys):
1513
yield node[0], node[1], node[2], ()
1514
found_keys.add(node[1])
1516
missing_keys = keys.difference(found_keys)
1518
raise RevisionNotPresent(missing_keys.pop(), self)
1520
def _present_keys(self, version_ids):
1522
node[1] for node in self._get_entries(version_ids)])
1524
def _parentless_ancestry(self, versions):
1525
"""Honour the get_ancestry API for parentless knit indices."""
1526
wanted_keys = self._version_ids_to_keys(versions)
1527
present_keys = self._present_keys(wanted_keys)
1528
missing = set(wanted_keys).difference(present_keys)
1530
raise RevisionNotPresent(missing.pop(), self)
1531
return list(self._keys_to_version_ids(present_keys))
1533
def get_ancestry(self, versions, topo_sorted=True):
1534
"""See VersionedFile.get_ancestry."""
1535
if not self._parents:
1536
return self._parentless_ancestry(versions)
1537
# XXX: This will do len(history) index calls - perhaps
1538
# it should be altered to be a index core feature?
1539
# get a graph of all the mentioned versions:
1542
versions = self._version_ids_to_keys(versions)
1543
pending = set(versions)
1545
# get all pending nodes
1546
this_iteration = pending
1547
new_nodes = self._get_entries(this_iteration)
1550
for (index, key, value, node_refs) in new_nodes:
1551
# dont ask for ghosties - otherwise
1552
# we we can end up looping with pending
1553
# being entirely ghosted.
1554
graph[key] = [parent for parent in node_refs[0]
1555
if parent not in ghosts]
1557
for parent in graph[key]:
1558
# dont examine known nodes again
1563
ghosts.update(this_iteration.difference(found))
1564
if versions.difference(graph):
1565
raise RevisionNotPresent(versions.difference(graph).pop(), self)
1567
result_keys = topo_sort(graph.items())
1569
result_keys = graph.iterkeys()
1570
return [key[0] for key in result_keys]
1572
def get_ancestry_with_ghosts(self, versions):
1573
"""See VersionedFile.get_ancestry."""
1574
if not self._parents:
1575
return self._parentless_ancestry(versions)
1576
# XXX: This will do len(history) index calls - perhaps
1577
# it should be altered to be a index core feature?
1578
# get a graph of all the mentioned versions:
1580
versions = self._version_ids_to_keys(versions)
1581
pending = set(versions)
1583
# get all pending nodes
1584
this_iteration = pending
1585
new_nodes = self._get_entries(this_iteration)
1587
for (index, key, value, node_refs) in new_nodes:
1588
graph[key] = node_refs[0]
1590
for parent in graph[key]:
1591
# dont examine known nodes again
1595
missing_versions = this_iteration.difference(graph)
1596
missing_needed = versions.intersection(missing_versions)
1598
raise RevisionNotPresent(missing_needed.pop(), self)
1599
for missing_version in missing_versions:
1600
# add a key, no parents
1601
graph[missing_version] = []
1602
pending.discard(missing_version) # don't look for it
1603
result_keys = topo_sort(graph.items())
1604
return [key[0] for key in result_keys]
1606
def get_graph(self):
1607
"""Return a list of the node:parents lists from this knit index."""
1608
if not self._parents:
1609
return [(key, ()) for key in self.get_versions()]
1611
for index, key, value, refs in self._graph_index.iter_all_entries():
1612
result.append((key[0], tuple([ref[0] for ref in refs[0]])))
1615
def iter_parents(self, version_ids):
1616
"""Iterate through the parents for many version ids.
1618
:param version_ids: An iterable yielding version_ids.
1619
:return: An iterator that yields (version_id, parents). Requested
1620
version_ids not present in the versioned file are simply skipped.
1621
The order is undefined, allowing for different optimisations in
1622
the underlying implementation.
1625
all_nodes = set(self._get_entries(self._version_ids_to_keys(version_ids)))
1627
present_parents = set()
1628
for node in all_nodes:
1629
all_parents.update(node[3][0])
1630
# any node we are querying must be present
1631
present_parents.add(node[1])
1632
unknown_parents = all_parents.difference(present_parents)
1633
present_parents.update(self._present_keys(unknown_parents))
1634
for node in all_nodes:
1636
for parent in node[3][0]:
1637
if parent in present_parents:
1638
parents.append(parent[0])
1639
yield node[1][0], tuple(parents)
1641
for node in self._get_entries(self._version_ids_to_keys(version_ids)):
1642
yield node[1][0], ()
1644
def num_versions(self):
1645
return len(list(self._graph_index.iter_all_entries()))
1647
__len__ = num_versions
1649
def get_versions(self):
1650
"""Get all the versions in the file. not topologically sorted."""
1651
return [node[1][0] for node in self._graph_index.iter_all_entries()]
1653
def has_version(self, version_id):
1654
"""True if the version is in the index."""
1655
return len(self._present_keys(self._version_ids_to_keys([version_id]))) == 1
1657
def _keys_to_version_ids(self, keys):
1658
return tuple(key[0] for key in keys)
1660
def get_position(self, version_id):
1661
"""Return details needed to access the version.
1663
:return: a tuple (index, data position, size) to hand to the access
1664
logic to get the record.
1666
node = self._get_node(version_id)
1667
bits = node[2][1:].split(' ')
1668
return node[0], int(bits[0]), int(bits[1])
1670
def get_method(self, version_id):
1671
"""Return compression method of specified version."""
1672
if not self._deltas:
1674
return self._parent_compression(self._get_node(version_id)[3][1])
1676
def _parent_compression(self, reference_list):
1677
# use the second reference list to decide if this is delta'd or not.
1678
if len(reference_list):
1683
def _get_node(self, version_id):
1684
return list(self._get_entries(self._version_ids_to_keys([version_id])))[0]
1686
def get_options(self, version_id):
1687
"""Return a string represention options.
1691
node = self._get_node(version_id)
1692
if not self._deltas:
1693
options = ['fulltext']
1695
options = [self._parent_compression(node[3][1])]
1696
if node[2][0] == 'N':
1697
options.append('no-eol')
1700
def get_parents(self, version_id):
1701
"""Return parents of specified version ignoring ghosts."""
1702
parents = list(self.iter_parents([version_id]))
1705
raise errors.RevisionNotPresent(version_id, self)
1706
return parents[0][1]
1708
def get_parents_with_ghosts(self, version_id):
1709
"""Return parents of specified version with ghosts."""
1710
nodes = list(self._get_entries(self._version_ids_to_keys([version_id]),
1711
check_present=True))
1712
if not self._parents:
1714
return self._keys_to_version_ids(nodes[0][3][0])
1716
def check_versions_present(self, version_ids):
1717
"""Check that all specified versions are present."""
1718
keys = self._version_ids_to_keys(version_ids)
1719
present = self._present_keys(keys)
1720
missing = keys.difference(present)
1722
raise RevisionNotPresent(missing.pop(), self)
1724
def add_version(self, version_id, options, access_memo, parents):
1725
"""Add a version record to the index."""
1726
return self.add_versions(((version_id, options, access_memo, parents),))
1728
def add_versions(self, versions):
1729
"""Add multiple versions to the index.
1731
This function does not insert data into the Immutable GraphIndex
1732
backing the KnitGraphIndex, instead it prepares data for insertion by
1733
the caller and checks that it is safe to insert then calls
1734
self._add_callback with the prepared GraphIndex nodes.
1736
:param versions: a list of tuples:
1737
(version_id, options, pos, size, parents).
1739
if not self._add_callback:
1740
raise errors.ReadOnlyError(self)
1741
# we hope there are no repositories with inconsistent parentage
1746
for (version_id, options, access_memo, parents) in versions:
1747
index, pos, size = access_memo
1748
key = (version_id, )
1749
parents = tuple((parent, ) for parent in parents)
1750
if 'no-eol' in options:
1754
value += "%d %d" % (pos, size)
1755
if not self._deltas:
1756
if 'line-delta' in options:
1757
raise KnitCorrupt(self, "attempt to add line-delta in non-delta knit")
1760
if 'line-delta' in options:
1761
node_refs = (parents, (parents[0],))
1763
node_refs = (parents, ())
1765
node_refs = (parents, )
1768
raise KnitCorrupt(self, "attempt to add node with parents "
1769
"in parentless index.")
1771
keys[key] = (value, node_refs)
1772
present_nodes = self._get_entries(keys)
1773
for (index, key, value, node_refs) in present_nodes:
1774
if (value, node_refs) != keys[key]:
1775
raise KnitCorrupt(self, "inconsistent details in add_versions"
1776
": %s %s" % ((value, node_refs), keys[key]))
1780
for key, (value, node_refs) in keys.iteritems():
1781
result.append((key, value, node_refs))
1783
for key, (value, node_refs) in keys.iteritems():
1784
result.append((key, value))
1785
self._add_callback(result)
1787
def _version_ids_to_keys(self, version_ids):
1788
return set((version_id, ) for version_id in version_ids)
1791
class _KnitAccess(object):
1792
"""Access to knit records in a .knit file."""
1794
def __init__(self, transport, filename, _file_mode, _dir_mode,
1795
_need_to_create, _create_parent_dir):
1796
"""Create a _KnitAccess for accessing and inserting data.
1798
:param transport: The transport the .knit is located on.
1799
:param filename: The filename of the .knit.
1801
self._transport = transport
1802
self._filename = filename
1803
self._file_mode = _file_mode
1804
self._dir_mode = _dir_mode
1805
self._need_to_create = _need_to_create
1806
self._create_parent_dir = _create_parent_dir
1808
def add_raw_records(self, sizes, raw_data):
1809
"""Add raw knit bytes to a storage area.
1811
The data is spooled to whereever the access method is storing data.
1813
:param sizes: An iterable containing the size of each raw data segment.
1814
:param raw_data: A bytestring containing the data.
1815
:return: A list of memos to retrieve the record later. Each memo is a
1816
tuple - (index, pos, length), where the index field is always None
1817
for the .knit access method.
1819
assert type(raw_data) == str, \
1820
'data must be plain bytes was %s' % type(raw_data)
1821
if not self._need_to_create:
1822
base = self._transport.append_bytes(self._filename, raw_data)
1824
self._transport.put_bytes_non_atomic(self._filename, raw_data,
1825
create_parent_dir=self._create_parent_dir,
1826
mode=self._file_mode,
1827
dir_mode=self._dir_mode)
1828
self._need_to_create = False
1832
result.append((None, base, size))
1837
"""IFF this data access has its own storage area, initialise it.
1841
self._transport.put_bytes_non_atomic(self._filename, '',
1842
mode=self._file_mode)
1844
def open_file(self):
1845
"""IFF this data access can be represented as a single file, open it.
1847
For knits that are not mapped to a single file on disk this will
1850
:return: None or a file handle.
1853
return self._transport.get(self._filename)
1858
def get_raw_records(self, memos_for_retrieval):
1859
"""Get the raw bytes for a records.
1861
:param memos_for_retrieval: An iterable containing the (index, pos,
1862
length) memo for retrieving the bytes. The .knit method ignores
1863
the index as there is always only a single file.
1864
:return: An iterator over the bytes of the records.
1866
read_vector = [(pos, size) for (index, pos, size) in memos_for_retrieval]
1867
for pos, data in self._transport.readv(self._filename, read_vector):
1871
class _PackAccess(object):
1872
"""Access to knit records via a collection of packs."""
1874
def __init__(self, index_to_packs, writer=None):
1875
"""Create a _PackAccess object.
1877
:param index_to_packs: A dict mapping index objects to the transport
1878
and file names for obtaining data.
1879
:param writer: A tuple (pack.ContainerWriter, write_index) which
1880
contains the pack to write, and the index that reads from it will
1884
self.container_writer = writer[0]
1885
self.write_index = writer[1]
1887
self.container_writer = None
1888
self.write_index = None
1889
self.indices = index_to_packs
1891
def add_raw_records(self, sizes, raw_data):
1892
"""Add raw knit bytes to a storage area.
1894
The data is spooled to the container writer in one bytes-record per
1897
:param sizes: An iterable containing the size of each raw data segment.
1898
:param raw_data: A bytestring containing the data.
1899
:return: A list of memos to retrieve the record later. Each memo is a
1900
tuple - (index, pos, length), where the index field is the
1901
write_index object supplied to the PackAccess object.
1903
assert type(raw_data) == str, \
1904
'data must be plain bytes was %s' % type(raw_data)
1908
p_offset, p_length = self.container_writer.add_bytes_record(
1909
raw_data[offset:offset+size], [])
1911
result.append((self.write_index, p_offset, p_length))
1915
"""Pack based knits do not get individually created."""
1917
def get_raw_records(self, memos_for_retrieval):
1918
"""Get the raw bytes for a records.
1920
:param memos_for_retrieval: An iterable containing the (index, pos,
1921
length) memo for retrieving the bytes. The Pack access method
1922
looks up the pack to use for a given record in its index_to_pack
1924
:return: An iterator over the bytes of the records.
1926
# first pass, group into same-index requests
1928
current_index = None
1929
for (index, offset, length) in memos_for_retrieval:
1930
if current_index == index:
1931
current_list.append((offset, length))
1933
if current_index is not None:
1934
request_lists.append((current_index, current_list))
1935
current_index = index
1936
current_list = [(offset, length)]
1937
# handle the last entry
1938
if current_index is not None:
1939
request_lists.append((current_index, current_list))
1940
for index, offsets in request_lists:
1941
transport, path = self.indices[index]
1942
reader = pack.make_readv_reader(transport, path, offsets)
1943
for names, read_func in reader.iter_records():
1944
yield read_func(None)
1946
def open_file(self):
1947
"""Pack based knits have no single file."""
1950
def set_writer(self, writer, index, (transport, packname)):
1951
"""Set a writer to use for adding data."""
1952
self.indices[index] = (transport, packname)
1953
self.container_writer = writer
1954
self.write_index = index
1957
class _KnitData(object):
1958
"""Manage extraction of data from a KnitAccess, caching and decompressing.
1960
The KnitData class provides the logic for parsing and using knit records,
1961
making use of an access method for the low level read and write operations.
1964
def __init__(self, access):
1965
"""Create a KnitData object.
1967
:param access: The access method to use. Access methods such as
1968
_KnitAccess manage the insertion of raw records and the subsequent
1969
retrieval of the same.
1971
self._access = access
1972
self._checked = False
1973
# TODO: jam 20060713 conceptually, this could spill to disk
1974
# if the cached size gets larger than a certain amount
1975
# but it complicates the model a bit, so for now just use
1976
# a simple dictionary
1978
self._do_cache = False
1980
def enable_cache(self):
1981
"""Enable caching of reads."""
1982
self._do_cache = True
1984
def clear_cache(self):
1985
"""Clear the record cache."""
1986
self._do_cache = False
1989
def _open_file(self):
1990
return self._access.open_file()
1992
def _record_to_data(self, version_id, digest, lines):
1993
"""Convert version_id, digest, lines into a raw data block.
1995
:return: (len, a StringIO instance with the raw data ready to read.)
1998
data_file = GzipFile(None, mode='wb', fileobj=sio,
1999
compresslevel=Z_DEFAULT_COMPRESSION)
2001
assert isinstance(version_id, str)
2002
data_file.writelines(chain(
2003
["version %s %d %s\n" % (version_id,
2007
["end %s\n" % version_id]))
2014
def add_raw_records(self, sizes, raw_data):
2015
"""Append a prepared record to the data file.
2017
:param sizes: An iterable containing the size of each raw data segment.
2018
:param raw_data: A bytestring containing the data.
2019
:return: a list of index data for the way the data was stored.
2020
See the access method add_raw_records documentation for more
2023
return self._access.add_raw_records(sizes, raw_data)
2025
def add_record(self, version_id, digest, lines):
2026
"""Write new text record to disk.
2028
Returns index data for retrieving it later, as per add_raw_records.
2030
size, sio = self._record_to_data(version_id, digest, lines)
2031
result = self.add_raw_records([size], sio.getvalue())
2033
self._cache[version_id] = sio.getvalue()
2036
def _parse_record_header(self, version_id, raw_data):
2037
"""Parse a record header for consistency.
2039
:return: the header and the decompressor stream.
2040
as (stream, header_record)
2042
df = GzipFile(mode='rb', fileobj=StringIO(raw_data))
2044
rec = self._check_header(version_id, df.readline())
2045
except Exception, e:
2046
raise KnitCorrupt(self._access,
2047
"While reading {%s} got %s(%s)"
2048
% (version_id, e.__class__.__name__, str(e)))
2051
def _check_header(self, version_id, line):
2054
raise KnitCorrupt(self._access,
2055
'unexpected number of elements in record header')
2056
if rec[1] != version_id:
2057
raise KnitCorrupt(self._access,
2058
'unexpected version, wanted %r, got %r'
2059
% (version_id, rec[1]))
2062
def _parse_record(self, version_id, data):
2064
# 4168 calls in 2880 217 internal
2065
# 4168 calls to _parse_record_header in 2121
2066
# 4168 calls to readlines in 330
2067
df = GzipFile(mode='rb', fileobj=StringIO(data))
2070
record_contents = df.readlines()
2071
except Exception, e:
2072
raise KnitCorrupt(self._access,
2073
"While reading {%s} got %s(%s)"
2074
% (version_id, e.__class__.__name__, str(e)))
2075
header = record_contents.pop(0)
2076
rec = self._check_header(version_id, header)
2078
last_line = record_contents.pop()
2079
if len(record_contents) != int(rec[2]):
2080
raise KnitCorrupt(self._access,
2081
'incorrect number of lines %s != %s'
2083
% (len(record_contents), int(rec[2]),
2085
if last_line != 'end %s\n' % rec[1]:
2086
raise KnitCorrupt(self._access,
2087
'unexpected version end line %r, wanted %r'
2088
% (last_line, version_id))
2090
return record_contents, rec[3]
2092
def read_records_iter_raw(self, records):
2093
"""Read text records from data file and yield raw data.
2095
This unpacks enough of the text record to validate the id is
2096
as expected but thats all.
2098
# setup an iterator of the external records:
2099
# uses readv so nice and fast we hope.
2101
# grab the disk data needed.
2103
# Don't check _cache if it is empty
2104
needed_offsets = [index_memo for version_id, index_memo
2106
if version_id not in self._cache]
2108
needed_offsets = [index_memo for version_id, index_memo
2111
raw_records = self._access.get_raw_records(needed_offsets)
2113
for version_id, index_memo in records:
2114
if version_id in self._cache:
2115
# This data has already been validated
2116
data = self._cache[version_id]
2118
data = raw_records.next()
2120
self._cache[version_id] = data
2122
# validate the header
2123
df, rec = self._parse_record_header(version_id, data)
2125
yield version_id, data
2127
def read_records_iter(self, records):
2128
"""Read text records from data file and yield result.
2130
The result will be returned in whatever is the fastest to read.
2131
Not by the order requested. Also, multiple requests for the same
2132
record will only yield 1 response.
2133
:param records: A list of (version_id, pos, len) entries
2134
:return: Yields (version_id, contents, digest) in the order
2135
read, not the order requested
2141
# Skip records we have alread seen
2142
yielded_records = set()
2143
needed_records = set()
2144
for record in records:
2145
if record[0] in self._cache:
2146
if record[0] in yielded_records:
2148
yielded_records.add(record[0])
2149
data = self._cache[record[0]]
2150
content, digest = self._parse_record(record[0], data)
2151
yield (record[0], content, digest)
2153
needed_records.add(record)
2154
needed_records = sorted(needed_records, key=operator.itemgetter(1))
2156
needed_records = sorted(set(records), key=operator.itemgetter(1))
2158
if not needed_records:
2161
# The transport optimizes the fetching as well
2162
# (ie, reads continuous ranges.)
2163
raw_data = self._access.get_raw_records(
2164
[index_memo for version_id, index_memo in needed_records])
2166
for (version_id, index_memo), data in \
2167
izip(iter(needed_records), raw_data):
2168
content, digest = self._parse_record(version_id, data)
2170
self._cache[version_id] = data
2171
yield version_id, content, digest
2173
def read_records(self, records):
2174
"""Read records into a dictionary."""
2176
for record_id, content, digest in \
2177
self.read_records_iter(records):
2178
components[record_id] = (content, digest)
2182
class InterKnit(InterVersionedFile):
2183
"""Optimised code paths for knit to knit operations."""
2185
_matching_file_from_factory = KnitVersionedFile
2186
_matching_file_to_factory = KnitVersionedFile
2189
def is_compatible(source, target):
2190
"""Be compatible with knits. """
2192
return (isinstance(source, KnitVersionedFile) and
2193
isinstance(target, KnitVersionedFile))
2194
except AttributeError:
2197
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
2198
"""See InterVersionedFile.join."""
2199
assert isinstance(self.source, KnitVersionedFile)
2200
assert isinstance(self.target, KnitVersionedFile)
2202
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
2207
pb = ui.ui_factory.nested_progress_bar()
2209
version_ids = list(version_ids)
2210
if None in version_ids:
2211
version_ids.remove(None)
2213
self.source_ancestry = set(self.source.get_ancestry(version_ids))
2214
this_versions = set(self.target._index.get_versions())
2215
needed_versions = self.source_ancestry - this_versions
2216
cross_check_versions = self.source_ancestry.intersection(this_versions)
2217
mismatched_versions = set()
2218
for version in cross_check_versions:
2219
# scan to include needed parents.
2220
n1 = set(self.target.get_parents_with_ghosts(version))
2221
n2 = set(self.source.get_parents_with_ghosts(version))
2223
# FIXME TEST this check for cycles being introduced works
2224
# the logic is we have a cycle if in our graph we are an
2225
# ancestor of any of the n2 revisions.
2231
parent_ancestors = self.source.get_ancestry(parent)
2232
if version in parent_ancestors:
2233
raise errors.GraphCycleError([parent, version])
2234
# ensure this parent will be available later.
2235
new_parents = n2.difference(n1)
2236
needed_versions.update(new_parents.difference(this_versions))
2237
mismatched_versions.add(version)
2239
if not needed_versions and not mismatched_versions:
2241
full_list = topo_sort(self.source.get_graph())
2243
version_list = [i for i in full_list if (not self.target.has_version(i)
2244
and i in needed_versions)]
2248
copy_queue_records = []
2250
for version_id in version_list:
2251
options = self.source._index.get_options(version_id)
2252
parents = self.source._index.get_parents_with_ghosts(version_id)
2253
# check that its will be a consistent copy:
2254
for parent in parents:
2255
# if source has the parent, we must :
2256
# * already have it or
2257
# * have it scheduled already
2258
# otherwise we don't care
2259
assert (self.target.has_version(parent) or
2260
parent in copy_set or
2261
not self.source.has_version(parent))
2262
index_memo = self.source._index.get_position(version_id)
2263
copy_queue_records.append((version_id, index_memo))
2264
copy_queue.append((version_id, options, parents))
2265
copy_set.add(version_id)
2267
# data suck the join:
2269
total = len(version_list)
2272
for (version_id, raw_data), \
2273
(version_id2, options, parents) in \
2274
izip(self.source._data.read_records_iter_raw(copy_queue_records),
2276
assert version_id == version_id2, 'logic error, inconsistent results'
2278
pb.update("Joining knit", count, total)
2279
raw_records.append((version_id, options, parents, len(raw_data)))
2280
raw_datum.append(raw_data)
2281
self.target._add_raw_records(raw_records, ''.join(raw_datum))
2283
for version in mismatched_versions:
2284
# FIXME RBC 20060309 is this needed?
2285
n1 = set(self.target.get_parents_with_ghosts(version))
2286
n2 = set(self.source.get_parents_with_ghosts(version))
2287
# write a combined record to our history preserving the current
2288
# parents as first in the list
2289
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
2290
self.target.fix_parents(version, new_parents)
2296
InterVersionedFile.register_optimiser(InterKnit)
2299
class WeaveToKnit(InterVersionedFile):
2300
"""Optimised code paths for weave to knit operations."""
2302
_matching_file_from_factory = bzrlib.weave.WeaveFile
2303
_matching_file_to_factory = KnitVersionedFile
2306
def is_compatible(source, target):
2307
"""Be compatible with weaves to knits."""
2309
return (isinstance(source, bzrlib.weave.Weave) and
2310
isinstance(target, KnitVersionedFile))
2311
except AttributeError:
2314
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
2315
"""See InterVersionedFile.join."""
2316
assert isinstance(self.source, bzrlib.weave.Weave)
2317
assert isinstance(self.target, KnitVersionedFile)
2319
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
2324
pb = ui.ui_factory.nested_progress_bar()
2326
version_ids = list(version_ids)
2328
self.source_ancestry = set(self.source.get_ancestry(version_ids))
2329
this_versions = set(self.target._index.get_versions())
2330
needed_versions = self.source_ancestry - this_versions
2331
cross_check_versions = self.source_ancestry.intersection(this_versions)
2332
mismatched_versions = set()
2333
for version in cross_check_versions:
2334
# scan to include needed parents.
2335
n1 = set(self.target.get_parents_with_ghosts(version))
2336
n2 = set(self.source.get_parents(version))
2337
# if all of n2's parents are in n1, then its fine.
2338
if n2.difference(n1):
2339
# FIXME TEST this check for cycles being introduced works
2340
# the logic is we have a cycle if in our graph we are an
2341
# ancestor of any of the n2 revisions.
2347
parent_ancestors = self.source.get_ancestry(parent)
2348
if version in parent_ancestors:
2349
raise errors.GraphCycleError([parent, version])
2350
# ensure this parent will be available later.
2351
new_parents = n2.difference(n1)
2352
needed_versions.update(new_parents.difference(this_versions))
2353
mismatched_versions.add(version)
2355
if not needed_versions and not mismatched_versions:
2357
full_list = topo_sort(self.source.get_graph())
2359
version_list = [i for i in full_list if (not self.target.has_version(i)
2360
and i in needed_versions)]
2364
total = len(version_list)
2365
for version_id in version_list:
2366
pb.update("Converting to knit", count, total)
2367
parents = self.source.get_parents(version_id)
2368
# check that its will be a consistent copy:
2369
for parent in parents:
2370
# if source has the parent, we must already have it
2371
assert (self.target.has_version(parent))
2372
self.target.add_lines(
2373
version_id, parents, self.source.get_lines(version_id))
2376
for version in mismatched_versions:
2377
# FIXME RBC 20060309 is this needed?
2378
n1 = set(self.target.get_parents_with_ghosts(version))
2379
n2 = set(self.source.get_parents(version))
2380
# write a combined record to our history preserving the current
2381
# parents as first in the list
2382
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
2383
self.target.fix_parents(version, new_parents)
2389
InterVersionedFile.register_optimiser(WeaveToKnit)
2392
class KnitSequenceMatcher(difflib.SequenceMatcher):
2393
"""Knit tuned sequence matcher.
2395
This is based on profiling of difflib which indicated some improvements
2396
for our usage pattern.
2399
def find_longest_match(self, alo, ahi, blo, bhi):
2400
"""Find longest matching block in a[alo:ahi] and b[blo:bhi].
2402
If isjunk is not defined:
2404
Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
2405
alo <= i <= i+k <= ahi
2406
blo <= j <= j+k <= bhi
2407
and for all (i',j',k') meeting those conditions,
2410
and if i == i', j <= j'
2412
In other words, of all maximal matching blocks, return one that
2413
starts earliest in a, and of all those maximal matching blocks that
2414
start earliest in a, return the one that starts earliest in b.
2416
>>> s = SequenceMatcher(None, " abcd", "abcd abcd")
2417
>>> s.find_longest_match(0, 5, 0, 9)
2420
If isjunk is defined, first the longest matching block is
2421
determined as above, but with the additional restriction that no
2422
junk element appears in the block. Then that block is extended as
2423
far as possible by matching (only) junk elements on both sides. So
2424
the resulting block never matches on junk except as identical junk
2425
happens to be adjacent to an "interesting" match.
2427
Here's the same example as before, but considering blanks to be
2428
junk. That prevents " abcd" from matching the " abcd" at the tail
2429
end of the second sequence directly. Instead only the "abcd" can
2430
match, and matches the leftmost "abcd" in the second sequence:
2432
>>> s = SequenceMatcher(lambda x: x==" ", " abcd", "abcd abcd")
2433
>>> s.find_longest_match(0, 5, 0, 9)
2436
If no blocks match, return (alo, blo, 0).
2438
>>> s = SequenceMatcher(None, "ab", "c")
2439
>>> s.find_longest_match(0, 2, 0, 1)
2443
# CAUTION: stripping common prefix or suffix would be incorrect.
2447
# Longest matching block is "ab", but if common prefix is
2448
# stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
2449
# strip, so ends up claiming that ab is changed to acab by
2450
# inserting "ca" in the middle. That's minimal but unintuitive:
2451
# "it's obvious" that someone inserted "ac" at the front.
2452
# Windiff ends up at the same place as diff, but by pairing up
2453
# the unique 'b's and then matching the first two 'a's.
2455
a, b, b2j, isbjunk = self.a, self.b, self.b2j, self.isbjunk
2456
besti, bestj, bestsize = alo, blo, 0
2457
# find longest junk-free match
2458
# during an iteration of the loop, j2len[j] = length of longest
2459
# junk-free match ending with a[i-1] and b[j]
2463
for i in xrange(alo, ahi):
2464
# look at all instances of a[i] in b; note that because
2465
# b2j has no junk keys, the loop is skipped if a[i] is junk
2466
j2lenget = j2len.get
2469
# changing b2j.get(a[i], nothing) to a try:KeyError pair produced the
2470
# following improvement
2471
# 704 0 4650.5320 2620.7410 bzrlib.knit:1336(find_longest_match)
2472
# +326674 0 1655.1210 1655.1210 +<method 'get' of 'dict' objects>
2473
# +76519 0 374.6700 374.6700 +<method 'has_key' of 'dict' objects>
2475
# 704 0 3733.2820 2209.6520 bzrlib.knit:1336(find_longest_match)
2476
# +211400 0 1147.3520 1147.3520 +<method 'get' of 'dict' objects>
2477
# +76519 0 376.2780 376.2780 +<method 'has_key' of 'dict' objects>
2489
k = newj2len[j] = 1 + j2lenget(-1 + j, 0)
2491
besti, bestj, bestsize = 1 + i-k, 1 + j-k, k
2494
# Extend the best by non-junk elements on each end. In particular,
2495
# "popular" non-junk elements aren't in b2j, which greatly speeds
2496
# the inner loop above, but also means "the best" match so far
2497
# doesn't contain any junk *or* popular non-junk elements.
2498
while besti > alo and bestj > blo and \
2499
not isbjunk(b[bestj-1]) and \
2500
a[besti-1] == b[bestj-1]:
2501
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
2502
while besti+bestsize < ahi and bestj+bestsize < bhi and \
2503
not isbjunk(b[bestj+bestsize]) and \
2504
a[besti+bestsize] == b[bestj+bestsize]:
2507
# Now that we have a wholly interesting match (albeit possibly
2508
# empty!), we may as well suck up the matching junk on each
2509
# side of it too. Can't think of a good reason not to, and it
2510
# saves post-processing the (possibly considerable) expense of
2511
# figuring out what to do with it. In the case of an empty
2512
# interesting match, this is clearly the right thing to do,
2513
# because no other kind of match is possible in the regions.
2514
while besti > alo and bestj > blo and \
2515
isbjunk(b[bestj-1]) and \
2516
a[besti-1] == b[bestj-1]:
2517
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
2518
while besti+bestsize < ahi and bestj+bestsize < bhi and \
2519
isbjunk(b[bestj+bestsize]) and \
2520
a[besti+bestsize] == b[bestj+bestsize]:
2521
bestsize = bestsize + 1
2523
return besti, bestj, bestsize
2527
from bzrlib._knit_load_data_c import _load_data_c as _load_data
2529
from bzrlib._knit_load_data_py import _load_data_py as _load_data
added
removed
bzrlib/knit.py
