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# Copyright (C) 2005, 2006 by Canonical Ltd
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# Written by Martin Pool.
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# Modified by Johan Rydberg <jrydberg@gnu.org>
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# Modified by Robert Collins <robert.collins@canonical.com>
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# Modified by Aaron Bentley <aaron.bentley@utoronto.ca>
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""Knit versionedfile implementation.
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A knit is a versioned file implementation that supports efficient append only
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lifeless: the data file is made up of "delta records". each delta record has a delta header
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that contains; (1) a version id, (2) the size of the delta (in lines), and (3) the digest of
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the -expanded data- (ie, the delta applied to the parent). the delta also ends with a
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end-marker; simply "end VERSION"
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delta can be line or full contents.a
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... the 8's there are the index number of the annotation.
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version robertc@robertcollins.net-20051003014215-ee2990904cc4c7ad 7 c7d23b2a5bd6ca00e8e266cec0ec228158ee9f9e
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8 e.set('executable', 'yes')
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8 if elt.get('executable') == 'yes':
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8 ie.executable = True
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end robertc@robertcollins.net-20051003014215-ee2990904cc4c7ad
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09:33 < jrydberg> lifeless: each index is made up of a tuple of; version id, options, position, size, parents
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09:33 < jrydberg> lifeless: the parents are currently dictionary compressed
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09:33 < jrydberg> lifeless: (meaning it currently does not support ghosts)
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09:33 < lifeless> right
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09:33 < jrydberg> lifeless: the position and size is the range in the data file
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so the index sequence is the dictionary compressed sequence number used
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in the deltas to provide line annotation
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# 10:16 < lifeless> make partial index writes safe
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# 10:16 < lifeless> implement 'knit.check()' like weave.check()
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# 10:17 < lifeless> record known ghosts so we can detect when they are filled in rather than the current 'reweave
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# move sha1 out of the content so that join is faster at verifying parents
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# record content length ?
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from cStringIO import StringIO
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from itertools import izip, chain
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from bzrlib.errors import FileExists, NoSuchFile, KnitError, \
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InvalidRevisionId, KnitCorrupt, KnitHeaderError, \
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RevisionNotPresent, RevisionAlreadyPresent
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from bzrlib.tuned_gzip import GzipFile
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from bzrlib.trace import mutter
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from bzrlib.osutils import contains_whitespace, contains_linebreaks, \
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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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for origin, text in 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 = [text for origin, text in new_lines._lines]
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old_texts = [text for origin, text in self._lines]
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s = KnitSequenceMatcher(None, old_texts, new_texts)
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for op in s.get_opcodes():
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# ofrom oto length data
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yield (op[1], op[2], op[4]-op[3], new_lines._lines[op[3]:op[4]])
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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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class _KnitFactory(object):
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"""Base factory for creating content objects."""
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def make(self, lines, version):
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num_lines = len(lines)
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return KnitContent(zip([version] * 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):
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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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decode_utf8 = cache_utf8.decode
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origin, text = line.split(' ', 1)
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lines.append((decode_utf8(origin), text))
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return KnitContent(lines)
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def parse_line_delta_iter(self, lines):
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for result_item in self.parse_line_delta[lines]:
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def parse_line_delta(self, lines, version):
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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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decode_utf8 = cache_utf8.decode
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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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origin, text = next().split(' ', 1)
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contents.append((decode_utf8(origin), text))
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result.append((start, end, count, contents))
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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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encode_utf8 = cache_utf8.encode
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return ['%s %s' % (encode_utf8(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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encode_utf8 = cache_utf8.encode
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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(encode_utf8(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):
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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)
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def parse_line_delta_iter(self, lines, version):
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header = lines.pop(0)
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start, end, c = [int(n) for n in header.split(',')]
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yield start, end, c, zip([version] * c, lines[:c])
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def parse_line_delta(self, lines, version):
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return list(self.parse_line_delta_iter(lines, version))
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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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"""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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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._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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self._data = _KnitData(transport, relpath + DATA_SUFFIX,
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access_mode, create=create and not len(self), file_mode=file_mode,
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create_parent_dir=create_parent_dir, delay_create=delay_create)
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return '%s(%s)' % (self.__class__.__name__,
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self.transport.abspath(self.filename))
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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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delta_parents = [delta_parent]
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parent = delta_parents[0]
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method = self._index.get_method(parent)
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if method == 'fulltext':
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delta_parents = self._index.get_parents(parent)
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if method == 'line-delta':
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# did not find a fulltext in the delta limit.
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# 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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where, size = self._data.add_record(version_id, digest, store_lines)
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self._index.add_version(version_id, options, where, size, 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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pos = self._data.add_raw_record(data)
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for (version_id, options, parents, size) in records:
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index_entries.append((version_id, options, pos+offset,
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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(name + INDEX_SUFFIX + '.tmp', self.transport.get(self._index._filename),)
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f = self._data._open_file()
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transport.put(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, delta=self.delta, create=True)
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def _fix_parents(self, version, 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]
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assert set(current_values[4]).difference(set(new_parents)) == set()
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self._index.add_version(version,
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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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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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data_pos, data_size = self._index.get_position(version_id)
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data, sha1 = self._data.read_records(((version_id, data_pos, data_size),))[version_id]
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version_idx = self._index.lookup(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_idx)
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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_idx)
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return parent, sha1, noeol, delta
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def get_graph_with_ghosts(self):
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"""See VersionedFile.get_graph_with_ghosts()."""
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graph_items = self._index.get_graph()
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return dict(graph_items)
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def get_sha1(self, version_id):
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"""See VersionedFile.get_sha1()."""
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record_map = self._get_record_map([version_id])
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method, content, digest, next = record_map[version_id]
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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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if self.has_version(version_id):
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# optimisable if needed by memoising the _ghosts set.
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items = self._index.get_graph()
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for node, parents in items:
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for parent in parents:
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if parent not in self._index._cache:
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if parent == version_id:
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"""See VersionedFile.versions."""
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return self._index.get_versions()
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def has_version(self, version_id):
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"""See VersionedFile.has_version."""
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return self._index.has_version(version_id)
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__contains__ = has_version
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def _merge_annotations(self, content, parents, parent_texts={},
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delta=None, annotated=None):
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"""Merge annotations for content. This is done by comparing
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the annotations based on changed to the text.
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for parent_id in parents:
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merge_content = self._get_content(parent_id, parent_texts)
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seq = KnitSequenceMatcher(None, merge_content.text(), content.text())
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if delta_seq is None:
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# setup a delta seq to reuse.
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for i, j, n in seq.get_matching_blocks():
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# this appears to copy (origin, text) pairs across to the new
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# content for any line that matches the last-checked parent.
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# FIXME: save the sequence control data for delta compression
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# against the most relevant parent rather than rediffing.
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content._lines[j:j+n] = merge_content._lines[i:i+n]
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reference_content = self._get_content(parents[0], parent_texts)
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new_texts = content.text()
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old_texts = reference_content.text()
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delta_seq = KnitSequenceMatcher(None, old_texts, new_texts)
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return self._make_line_delta(delta_seq, content)
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def _make_line_delta(self, delta_seq, new_content):
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"""Generate a line delta from delta_seq and new_content."""
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for op in delta_seq.get_opcodes():
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diff_hunks.append((op[1], op[2], op[4]-op[3], new_content._lines[op[3]:op[4]]))
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def _get_components_positions(self, version_ids):
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"""Produce a map of position data for the components of versions.
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This data is intended to be used for retrieving the knit records.
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A dict of version_id to (method, data_pos, data_size, next) is
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method is the way referenced data should be applied.
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data_pos is the position of the data in the knit.
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data_size is the size of the data in the knit.
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next is the build-parent of the version, or None for fulltexts.
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for version_id in version_ids:
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while cursor is not None and cursor not in component_data:
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method = self._index.get_method(cursor)
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if method == 'fulltext':
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next = self.get_parents(cursor)[0]
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data_pos, data_size = self._index.get_position(cursor)
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component_data[cursor] = (method, data_pos, data_size, next)
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return component_data
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def _get_content(self, version_id, parent_texts={}):
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"""Returns a content object that makes up the specified
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if not self.has_version(version_id):
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raise RevisionNotPresent(version_id, self.filename)
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cached_version = parent_texts.get(version_id, None)
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if cached_version is not None:
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return cached_version
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text_map, contents_map = self._get_content_maps([version_id])
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return contents_map[version_id]
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def _check_versions_present(self, version_ids):
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"""Check that all specified versions are present."""
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version_ids = set(version_ids)
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for r in list(version_ids):
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if self._index.has_version(r):
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version_ids.remove(r)
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raise RevisionNotPresent(list(version_ids)[0], self.filename)
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def _add_lines_with_ghosts(self, version_id, parents, lines, parent_texts):
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"""See VersionedFile.add_lines_with_ghosts()."""
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self._check_add(version_id, lines)
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return self._add(version_id, lines[:], parents, self.delta, parent_texts)
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def _add_lines(self, version_id, parents, lines, parent_texts):
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"""See VersionedFile.add_lines."""
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self._check_add(version_id, lines)
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self._check_versions_present(parents)
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return self._add(version_id, lines[:], parents, self.delta, parent_texts)
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def _check_add(self, version_id, lines):
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"""check that version_id and lines are safe to add."""
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assert self.writable, "knit is not opened for write"
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### FIXME escape. RBC 20060228
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if contains_whitespace(version_id):
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raise InvalidRevisionId(version_id, self.filename)
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if self.has_version(version_id):
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raise RevisionAlreadyPresent(version_id, self.filename)
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self._check_lines_not_unicode(lines)
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self._check_lines_are_lines(lines)
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def _add(self, version_id, lines, parents, delta, parent_texts):
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"""Add a set of lines on top of version specified by parents.
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If delta is true, compress the text as a line-delta against
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Any versions not present will be converted into ghosts.
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# 461 0 6546.0390 43.9100 bzrlib.knit:489(_add)
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# +400 0 889.4890 418.9790 +bzrlib.knit:192(lower_fulltext)
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# +461 0 1364.8070 108.8030 +bzrlib.knit:996(add_record)
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# +461 0 193.3940 41.5720 +bzrlib.knit:898(add_version)
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# +461 0 134.0590 18.3810 +bzrlib.osutils:361(sha_strings)
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# +461 0 36.3420 15.4540 +bzrlib.knit:146(make)
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# +1383 0 8.0370 8.0370 +<len>
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# +61 0 13.5770 7.9190 +bzrlib.knit:199(lower_line_delta)
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# +61 0 963.3470 7.8740 +bzrlib.knit:427(_get_content)
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# +61 0 973.9950 5.2950 +bzrlib.knit:136(line_delta)
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# +61 0 1918.1800 5.2640 +bzrlib.knit:359(_merge_annotations)
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if parent_texts is None:
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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 and not len(present_parents):
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digest = sha_strings(lines)
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if lines[-1][-1] != '\n':
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options.append('no-eol')
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lines[-1] = lines[-1] + '\n'
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if len(present_parents) and delta:
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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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delta_parents = present_parents
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parent = delta_parents[0]
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method = self._index.get_method(parent)
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if method == 'fulltext':
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delta_parents = self._index.get_parents(parent)
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if method == 'line-delta':
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lines = self.factory.make(lines, version_id)
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if delta or (self.factory.annotated and len(present_parents) > 0):
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# Merge annotations from parent texts if so is needed.
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delta_hunks = self._merge_annotations(lines, present_parents, parent_texts,
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delta, self.factory.annotated)
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options.append('line-delta')
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store_lines = self.factory.lower_line_delta(delta_hunks)
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options.append('fulltext')
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store_lines = self.factory.lower_fulltext(lines)
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where, size = self._data.add_record(version_id, digest, store_lines)
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self._index.add_version(version_id, options, where, size, parents)
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def check(self, progress_bar=None):
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"""See VersionedFile.check()."""
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def _clone_text(self, new_version_id, old_version_id, parents):
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"""See VersionedFile.clone_text()."""
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# FIXME RBC 20060228 make fast by only inserting an index with null
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self.add_lines(new_version_id, parents, self.get_lines(old_version_id))
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def get_lines(self, version_id):
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"""See VersionedFile.get_lines()."""
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return self.get_line_list([version_id])[0]
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def _get_record_map(self, version_ids):
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"""Produce a dictionary of knit records.
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The keys are version_ids, the values are tuples of (method, content,
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method is the way the content should be applied.
711
content is a KnitContent object.
712
digest is the SHA1 digest of this version id after all steps are done
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next is the build-parent of the version, i.e. the leftmost ancestor.
714
If the method is fulltext, next will be None.
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position_map = self._get_components_positions(version_ids)
717
# c = component_id, m = method, p = position, s = size, n = next
718
records = [(c, p, s) for c, (m, p, s, n) in position_map.iteritems()]
720
for component_id, content, digest in \
721
self._data.read_records_iter(records):
722
method, position, size, next = position_map[component_id]
723
record_map[component_id] = method, content, digest, next
727
def get_text(self, version_id):
728
"""See VersionedFile.get_text"""
729
return self.get_texts([version_id])[0]
731
def get_texts(self, version_ids):
732
return [''.join(l) for l in self.get_line_list(version_ids)]
734
def get_line_list(self, version_ids):
735
"""Return the texts of listed versions as a list of strings."""
736
text_map, content_map = self._get_content_maps(version_ids)
737
return [text_map[v] for v in version_ids]
739
def _get_content_maps(self, version_ids):
740
"""Produce maps of text and KnitContents
742
:return: (text_map, content_map) where text_map contains the texts for
743
the requested versions and content_map contains the KnitContents.
744
Both dicts take version_ids as their keys.
746
for version_id in version_ids:
747
if not self.has_version(version_id):
748
raise RevisionNotPresent(version_id, self.filename)
749
record_map = self._get_record_map(version_ids)
754
for version_id in version_ids:
757
while cursor is not None:
758
method, data, digest, next = record_map[cursor]
759
components.append((cursor, method, data, digest))
760
if cursor in content_map:
765
for component_id, method, data, digest in reversed(components):
766
if component_id in content_map:
767
content = content_map[component_id]
769
version_idx = self._index.lookup(component_id)
770
if method == 'fulltext':
771
assert content is None
772
content = self.factory.parse_fulltext(data, version_idx)
773
elif method == 'line-delta':
774
delta = self.factory.parse_line_delta(data[:],
776
content = content.copy()
777
content._lines = self._apply_delta(content._lines,
779
content_map[component_id] = content
781
if 'no-eol' in self._index.get_options(version_id):
782
content = content.copy()
783
line = content._lines[-1][1].rstrip('\n')
784
content._lines[-1] = (content._lines[-1][0], line)
785
final_content[version_id] = content
787
# digest here is the digest from the last applied component.
788
text = content.text()
789
if sha_strings(text) != digest:
790
raise KnitCorrupt(self.filename,
791
'sha-1 does not match %s' % version_id)
793
text_map[version_id] = text
794
return text_map, final_content
796
def iter_lines_added_or_present_in_versions(self, version_ids=None):
797
"""See VersionedFile.iter_lines_added_or_present_in_versions()."""
798
if version_ids is None:
799
version_ids = self.versions()
800
# we don't care about inclusions, the caller cares.
801
# but we need to setup a list of records to visit.
802
# we need version_id, position, length
803
version_id_records = []
804
requested_versions = list(version_ids)
805
# filter for available versions
806
for version_id in requested_versions:
807
if not self.has_version(version_id):
808
raise RevisionNotPresent(version_id, self.filename)
809
# get a in-component-order queue:
811
for version_id in self.versions():
812
if version_id in requested_versions:
813
version_ids.append(version_id)
814
data_pos, length = self._index.get_position(version_id)
815
version_id_records.append((version_id, data_pos, length))
817
pb = bzrlib.ui.ui_factory.nested_progress_bar()
819
total = len(version_id_records)
821
pb.update('Walking content.', count, total)
822
for version_id, data, sha_value in \
823
self._data.read_records_iter(version_id_records):
824
pb.update('Walking content.', count, total)
825
method = self._index.get_method(version_id)
826
version_idx = self._index.lookup(version_id)
827
assert method in ('fulltext', 'line-delta')
828
if method == 'fulltext':
829
content = self.factory.parse_fulltext(data, version_idx)
830
for line in content.text():
833
delta = self.factory.parse_line_delta(data, version_idx)
834
for start, end, count, lines in delta:
835
for origin, line in lines:
838
pb.update('Walking content.', total, total)
841
pb.update('Walking content.', total, total)
845
def num_versions(self):
846
"""See VersionedFile.num_versions()."""
847
return self._index.num_versions()
849
__len__ = num_versions
851
def annotate_iter(self, version_id):
852
"""See VersionedFile.annotate_iter."""
853
content = self._get_content(version_id)
854
for origin, text in content.annotate_iter():
857
def get_parents(self, version_id):
858
"""See VersionedFile.get_parents."""
861
# 52554 calls in 1264 872 internal down from 3674
863
return self._index.get_parents(version_id)
865
raise RevisionNotPresent(version_id, self.filename)
867
def get_parents_with_ghosts(self, version_id):
868
"""See VersionedFile.get_parents."""
870
return self._index.get_parents_with_ghosts(version_id)
872
raise RevisionNotPresent(version_id, self.filename)
874
def get_ancestry(self, versions):
875
"""See VersionedFile.get_ancestry."""
876
if isinstance(versions, basestring):
877
versions = [versions]
880
self._check_versions_present(versions)
881
return self._index.get_ancestry(versions)
883
def get_ancestry_with_ghosts(self, versions):
884
"""See VersionedFile.get_ancestry_with_ghosts."""
885
if isinstance(versions, basestring):
886
versions = [versions]
889
self._check_versions_present(versions)
890
return self._index.get_ancestry_with_ghosts(versions)
892
#@deprecated_method(zero_eight)
893
def walk(self, version_ids):
894
"""See VersionedFile.walk."""
895
# We take the short path here, and extract all relevant texts
896
# and put them in a weave and let that do all the work. Far
897
# from optimal, but is much simpler.
898
# FIXME RB 20060228 this really is inefficient!
899
from bzrlib.weave import Weave
901
w = Weave(self.filename)
902
ancestry = self.get_ancestry(version_ids)
903
sorted_graph = topo_sort(self._index.get_graph())
904
version_list = [vid for vid in sorted_graph if vid in ancestry]
906
for version_id in version_list:
907
lines = self.get_lines(version_id)
908
w.add_lines(version_id, self.get_parents(version_id), lines)
910
for lineno, insert_id, dset, line in w.walk(version_ids):
911
yield lineno, insert_id, dset, line
913
def plan_merge(self, ver_a, ver_b):
914
"""See VersionedFile.plan_merge."""
915
ancestors_b = set(self.get_ancestry(ver_b))
916
def status_a(revision, text):
917
if revision in ancestors_b:
918
return 'killed-b', text
922
ancestors_a = set(self.get_ancestry(ver_a))
923
def status_b(revision, text):
924
if revision in ancestors_a:
925
return 'killed-a', text
929
annotated_a = self.annotate(ver_a)
930
annotated_b = self.annotate(ver_b)
931
plain_a = [t for (a, t) in annotated_a]
932
plain_b = [t for (a, t) in annotated_b]
933
blocks = KnitSequenceMatcher(None, plain_a, plain_b).get_matching_blocks()
936
for ai, bi, l in blocks:
937
# process all mismatched sections
938
# (last mismatched section is handled because blocks always
939
# includes a 0-length last block)
940
for revision, text in annotated_a[a_cur:ai]:
941
yield status_a(revision, text)
942
for revision, text in annotated_b[b_cur:bi]:
943
yield status_b(revision, text)
945
# and now the matched section
948
for text_a, text_b in zip(plain_a[ai:a_cur], plain_b[bi:b_cur]):
949
assert text_a == text_b
950
yield "unchanged", text_a
953
class _KnitComponentFile(object):
954
"""One of the files used to implement a knit database"""
956
def __init__(self, transport, filename, mode, file_mode=None,
957
create_parent_dir=False):
958
self._transport = transport
959
self._filename = filename
961
self._file_mode=file_mode
962
self._create_parent_dir = create_parent_dir
963
self._need_to_create = False
965
def check_header(self, fp):
967
if line != self.HEADER:
968
raise KnitHeaderError(badline=line)
971
"""Commit is a nop."""
974
return '%s(%s)' % (self.__class__.__name__, self._filename)
977
class _KnitIndex(_KnitComponentFile):
978
"""Manages knit index file.
980
The index is already kept in memory and read on startup, to enable
981
fast lookups of revision information. The cursor of the index
982
file is always pointing to the end, making it easy to append
985
_cache is a cache for fast mapping from version id to a Index
988
_history is a cache for fast mapping from indexes to version ids.
990
The index data format is dictionary compressed when it comes to
991
parent references; a index entry may only have parents that with a
992
lover index number. As a result, the index is topological sorted.
994
Duplicate entries may be written to the index for a single version id
995
if this is done then the latter one completely replaces the former:
996
this allows updates to correct version and parent information.
997
Note that the two entries may share the delta, and that successive
998
annotations and references MUST point to the first entry.
1000
The index file on disc contains a header, followed by one line per knit
1001
record. The same revision can be present in an index file more than once.
1002
The first occurrence gets assigned a sequence number starting from 0.
1004
The format of a single line is
1005
REVISION_ID FLAGS BYTE_OFFSET LENGTH( PARENT_ID|PARENT_SEQUENCE_ID)* :\n
1006
REVISION_ID is a utf8-encoded revision id
1007
FLAGS is a comma separated list of flags about the record. Values include
1008
no-eol, line-delta, fulltext.
1009
BYTE_OFFSET is the ascii representation of the byte offset in the data file
1010
that the the compressed data starts at.
1011
LENGTH is the ascii representation of the length of the data file.
1012
PARENT_ID a utf-8 revision id prefixed by a '.' that is a parent of
1014
PARENT_SEQUENCE_ID the ascii representation of the sequence number of a
1015
revision id already in the knit that is a parent of REVISION_ID.
1016
The ' :' marker is the end of record marker.
1019
when a write is interrupted to the index file, it will result in a line that
1020
does not end in ' :'. If the ' :' is not present at the end of a line, or at
1021
the end of the file, then the record that is missing it will be ignored by
1024
When writing new records to the index file, the data is preceded by '\n'
1025
to ensure that records always start on new lines even if the last write was
1026
interrupted. As a result its normal for the last line in the index to be
1027
missing a trailing newline. One can be added with no harmful effects.
1030
HEADER = "# bzr knit index 8\n"
1032
# speed of knit parsing went from 280 ms to 280 ms with slots addition.
1033
# __slots__ = ['_cache', '_history', '_transport', '_filename']
1035
def _cache_version(self, version_id, options, pos, size, parents):
1036
"""Cache a version record in the history array and index cache.
1038
This is inlined into __init__ for performance. KEEP IN SYNC.
1039
(It saves 60ms, 25% of the __init__ overhead on local 4000 record
1042
# only want the _history index to reference the 1st index entry
1044
if version_id not in self._cache:
1045
index = len(self._history)
1046
self._history.append(version_id)
1048
index = self._cache[version_id][5]
1049
self._cache[version_id] = (version_id,
1056
def __init__(self, transport, filename, mode, create=False, file_mode=None,
1057
create_parent_dir=False, delay_create=False):
1058
_KnitComponentFile.__init__(self, transport, filename, mode, file_mode,
1059
create_parent_dir=create_parent_dir)
1061
# position in _history is the 'official' index for a revision
1062
# but the values may have come from a newer entry.
1063
# so - wc -l of a knit index is != the number of unique names
1066
pb = bzrlib.ui.ui_factory.nested_progress_bar()
1071
pb.update('read knit index', count, total)
1072
fp = self._transport.get(self._filename)
1074
self.check_header(fp)
1075
# readlines reads the whole file at once:
1076
# bad for transports like http, good for local disk
1077
# we save 60 ms doing this one change (
1078
# from calling readline each time to calling
1080
# probably what we want for nice behaviour on
1081
# http is a incremental readlines that yields, or
1082
# a check for local vs non local indexes,
1083
for l in fp.readlines():
1085
if len(rec) < 5 or rec[-1] != ':':
1087
# FIXME: in the future we should determine if its a
1088
# short write - and ignore it
1089
# or a different failure, and raise. RBC 20060407
1093
#pb.update('read knit index', count, total)
1094
# See self._parse_parents
1096
for value in rec[4:-1]:
1098
# uncompressed reference
1099
parents.append(value[1:])
1101
# this is 15/4000ms faster than isinstance,
1103
# this function is called thousands of times a
1104
# second so small variations add up.
1105
assert value.__class__ is str
1106
parents.append(self._history[int(value)])
1107
# end self._parse_parents
1108
# self._cache_version(rec[0],
1109
# rec[1].split(','),
1113
# --- self._cache_version
1114
# only want the _history index to reference the 1st
1115
# index entry for version_id
1117
if version_id not in self._cache:
1118
index = len(self._history)
1119
self._history.append(version_id)
1121
index = self._cache[version_id][5]
1122
self._cache[version_id] = (version_id,
1128
# --- self._cache_version
1131
except NoSuchFile, e:
1132
if mode != 'w' or not create:
1135
self._need_to_create = True
1137
self._transport.non_atomic_put(self._filename,
1138
StringIO(self.HEADER),
1139
mode=self._file_mode)
1142
pb.update('read knit index', total, total)
1145
def _parse_parents(self, compressed_parents):
1146
"""convert a list of string parent values into version ids.
1148
ints are looked up in the index.
1149
.FOO values are ghosts and converted in to FOO.
1151
NOTE: the function is retained here for clarity, and for possible
1152
use in partial index reads. However bulk processing now has
1153
it inlined in __init__ for inner-loop optimisation.
1156
for value in compressed_parents:
1157
if value[-1] == '.':
1158
# uncompressed reference
1159
result.append(value[1:])
1161
# this is 15/4000ms faster than isinstance,
1162
# this function is called thousands of times a
1163
# second so small variations add up.
1164
assert value.__class__ is str
1165
result.append(self._history[int(value)])
1168
def get_graph(self):
1170
for version_id, index in self._cache.iteritems():
1171
graph.append((version_id, index[4]))
1174
def get_ancestry(self, versions):
1175
"""See VersionedFile.get_ancestry."""
1176
# get a graph of all the mentioned versions:
1178
pending = set(versions)
1180
version = pending.pop()
1181
parents = self._cache[version][4]
1182
# got the parents ok
1184
parents = [parent for parent in parents if parent in self._cache]
1185
for parent in parents:
1186
# if not completed and not a ghost
1187
if parent not in graph:
1189
graph[version] = parents
1190
return topo_sort(graph.items())
1192
def get_ancestry_with_ghosts(self, versions):
1193
"""See VersionedFile.get_ancestry_with_ghosts."""
1194
# get a graph of all the mentioned versions:
1196
pending = set(versions)
1198
version = pending.pop()
1200
parents = self._cache[version][4]
1206
# got the parents ok
1207
for parent in parents:
1208
if parent not in graph:
1210
graph[version] = parents
1211
return topo_sort(graph.items())
1213
def num_versions(self):
1214
return len(self._history)
1216
__len__ = num_versions
1218
def get_versions(self):
1219
return self._history
1221
def idx_to_name(self, idx):
1222
return self._history[idx]
1224
def lookup(self, version_id):
1225
assert version_id in self._cache
1226
return self._cache[version_id][5]
1228
def _version_list_to_index(self, versions):
1229
encode_utf8 = cache_utf8.encode
1231
for version in versions:
1232
if version in self._cache:
1233
# -- inlined lookup() --
1234
result_list.append(str(self._cache[version][5]))
1235
# -- end lookup () --
1237
result_list.append('.' + encode_utf8(version))
1238
return ' '.join(result_list)
1240
def add_version(self, version_id, options, pos, size, parents):
1241
"""Add a version record to the index."""
1242
self.add_versions(((version_id, options, pos, size, parents),))
1244
def add_versions(self, versions):
1245
"""Add multiple versions to the index.
1247
:param versions: a list of tuples:
1248
(version_id, options, pos, size, parents).
1251
encode_utf8 = cache_utf8.encode
1252
for version_id, options, pos, size, parents in versions:
1253
line = "\n%s %s %s %s %s :" % (encode_utf8(version_id),
1257
self._version_list_to_index(parents))
1258
assert isinstance(line, str), \
1259
'content must be utf-8 encoded: %r' % (line,)
1261
if not self._need_to_create:
1262
self._transport.append(self._filename, StringIO(''.join(lines)))
1265
sio.write(self.HEADER)
1266
sio.writelines(lines)
1268
self._transport.non_atomic_put(self._filename, sio,
1269
create_parent_dir=self._create_parent_dir,
1270
mode=self._file_mode)
1271
self._need_to_create = False
1273
# cache after writing, so that a failed write leads to missing cache
1274
# entries not extra ones. XXX TODO: RBC 20060502 in the event of a
1275
# failure, reload the index or flush it or some such, to prevent
1276
# writing records that did complete twice.
1277
for version_id, options, pos, size, parents in versions:
1278
self._cache_version(version_id, options, pos, size, parents)
1280
def has_version(self, version_id):
1281
"""True if the version is in the index."""
1282
return self._cache.has_key(version_id)
1284
def get_position(self, version_id):
1285
"""Return data position and size of specified version."""
1286
return (self._cache[version_id][2], \
1287
self._cache[version_id][3])
1289
def get_method(self, version_id):
1290
"""Return compression method of specified version."""
1291
options = self._cache[version_id][1]
1292
if 'fulltext' in options:
1295
assert 'line-delta' in options
1298
def get_options(self, version_id):
1299
return self._cache[version_id][1]
1301
def get_parents(self, version_id):
1302
"""Return parents of specified version ignoring ghosts."""
1303
return [parent for parent in self._cache[version_id][4]
1304
if parent in self._cache]
1306
def get_parents_with_ghosts(self, version_id):
1307
"""Return parents of specified version with ghosts."""
1308
return self._cache[version_id][4]
1310
def check_versions_present(self, version_ids):
1311
"""Check that all specified versions are present."""
1312
version_ids = set(version_ids)
1313
for version_id in list(version_ids):
1314
if version_id in self._cache:
1315
version_ids.remove(version_id)
1317
raise RevisionNotPresent(list(version_ids)[0], self.filename)
1320
class _KnitData(_KnitComponentFile):
1321
"""Contents of the knit data file"""
1323
def __init__(self, transport, filename, mode, create=False, file_mode=None,
1324
create_parent_dir=False, delay_create=False):
1325
_KnitComponentFile.__init__(self, transport, filename, mode,
1326
create_parent_dir=create_parent_dir)
1327
self._checked = False
1328
# TODO: jam 20060713 conceptually, this could spill to disk
1329
# if the cached size gets larger than a certain amount
1330
# but it complicates the model a bit, so for now just use
1331
# a simple dictionary
1333
self._do_cache = False
1336
self._need_to_create = create
1338
self._transport.non_atomic_put(self._filename, StringIO(''))
1340
def enable_cache(self):
1341
"""Enable caching of reads."""
1342
self._do_cache = True
1344
def clear_cache(self):
1345
"""Clear the record cache."""
1346
self._do_cache = False
1349
def _open_file(self):
1351
return self._transport.get(self._filename)
1356
def _record_to_data(self, version_id, digest, lines):
1357
"""Convert version_id, digest, lines into a raw data block.
1359
:return: (len, a StringIO instance with the raw data ready to read.)
1362
data_file = GzipFile(None, mode='wb', fileobj=sio)
1364
version_id_utf8 = cache_utf8.encode(version_id)
1365
data_file.writelines(chain(
1366
["version %s %d %s\n" % (version_id_utf8,
1370
["end %s\n" % version_id_utf8]))
1377
def add_raw_record(self, raw_data):
1378
"""Append a prepared record to the data file.
1380
:return: the offset in the data file raw_data was written.
1382
assert isinstance(raw_data, str), 'data must be plain bytes'
1383
if not self._need_to_create:
1384
return self._transport.append(self._filename, StringIO(raw_data))
1386
self._transport.non_atomic_put(self._filename, StringIO(raw_data),
1387
create_parent_dir=self._create_parent_dir,
1388
mode=self._file_mode)
1389
self._need_to_create = False
1392
def add_record(self, version_id, digest, lines):
1393
"""Write new text record to disk. Returns the position in the
1394
file where it was written."""
1395
size, sio = self._record_to_data(version_id, digest, lines)
1397
if not self._need_to_create:
1398
start_pos = self._transport.append(self._filename, sio)
1400
self._transport.non_atomic_put(self._filename, sio,
1401
create_parent_dir=self._create_parent_dir,
1402
mode=self._file_mode)
1403
self._need_to_create = False
1406
self._cache[version_id] = sio.getvalue()
1407
return start_pos, size
1409
def _parse_record_header(self, version_id, raw_data):
1410
"""Parse a record header for consistency.
1412
:return: the header and the decompressor stream.
1413
as (stream, header_record)
1415
df = GzipFile(mode='rb', fileobj=StringIO(raw_data))
1416
rec = df.readline().split()
1418
raise KnitCorrupt(self._filename, 'unexpected number of elements in record header')
1419
if cache_utf8.decode(rec[1]) != version_id:
1420
raise KnitCorrupt(self._filename,
1421
'unexpected version, wanted %r, got %r' % (
1422
version_id, rec[1]))
1425
def _parse_record(self, version_id, data):
1427
# 4168 calls in 2880 217 internal
1428
# 4168 calls to _parse_record_header in 2121
1429
# 4168 calls to readlines in 330
1430
df, rec = self._parse_record_header(version_id, data)
1431
record_contents = df.readlines()
1432
l = record_contents.pop()
1433
assert len(record_contents) == int(rec[2])
1434
if l != 'end %s\n' % cache_utf8.encode(version_id):
1435
raise KnitCorrupt(self._filename, 'unexpected version end line %r, wanted %r'
1438
return record_contents, rec[3]
1440
def read_records_iter_raw(self, records):
1441
"""Read text records from data file and yield raw data.
1443
This unpacks enough of the text record to validate the id is
1444
as expected but thats all.
1446
# setup an iterator of the external records:
1447
# uses readv so nice and fast we hope.
1449
# grab the disk data needed.
1451
# Don't check _cache if it is empty
1452
needed_offsets = [(pos, size) for version_id, pos, size
1454
if version_id not in self._cache]
1456
needed_offsets = [(pos, size) for version_id, pos, size
1459
raw_records = self._transport.readv(self._filename, needed_offsets)
1462
for version_id, pos, size in records:
1463
if version_id in self._cache:
1464
# This data has already been validated
1465
data = self._cache[version_id]
1467
pos, data = raw_records.next()
1469
self._cache[version_id] = data
1471
# validate the header
1472
df, rec = self._parse_record_header(version_id, data)
1474
yield version_id, data
1476
def read_records_iter(self, records):
1477
"""Read text records from data file and yield result.
1479
The result will be returned in whatever is the fastest to read.
1480
Not by the order requested. Also, multiple requests for the same
1481
record will only yield 1 response.
1482
:param records: A list of (version_id, pos, len) entries
1483
:return: Yields (version_id, contents, digest) in the order
1484
read, not the order requested
1490
# Skip records we have alread seen
1491
yielded_records = set()
1492
needed_records = set()
1493
for record in records:
1494
if record[0] in self._cache:
1495
if record[0] in yielded_records:
1497
yielded_records.add(record[0])
1498
data = self._cache[record[0]]
1499
content, digest = self._parse_record(record[0], data)
1500
yield (record[0], content, digest)
1502
needed_records.add(record)
1503
needed_records = sorted(needed_records, key=operator.itemgetter(1))
1505
needed_records = sorted(set(records), key=operator.itemgetter(1))
1507
if not needed_records:
1510
# The transport optimizes the fetching as well
1511
# (ie, reads continuous ranges.)
1512
readv_response = self._transport.readv(self._filename,
1513
[(pos, size) for version_id, pos, size in needed_records])
1515
for (version_id, pos, size), (pos, data) in \
1516
izip(iter(needed_records), readv_response):
1517
content, digest = self._parse_record(version_id, data)
1519
self._cache[version_id] = data
1520
yield version_id, content, digest
1522
def read_records(self, records):
1523
"""Read records into a dictionary."""
1525
for record_id, content, digest in \
1526
self.read_records_iter(records):
1527
components[record_id] = (content, digest)
1531
class InterKnit(InterVersionedFile):
1532
"""Optimised code paths for knit to knit operations."""
1534
_matching_file_from_factory = KnitVersionedFile
1535
_matching_file_to_factory = KnitVersionedFile
1538
def is_compatible(source, target):
1539
"""Be compatible with knits. """
1541
return (isinstance(source, KnitVersionedFile) and
1542
isinstance(target, KnitVersionedFile))
1543
except AttributeError:
1546
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
1547
"""See InterVersionedFile.join."""
1548
assert isinstance(self.source, KnitVersionedFile)
1549
assert isinstance(self.target, KnitVersionedFile)
1551
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
1556
pb = bzrlib.ui.ui_factory.nested_progress_bar()
1558
version_ids = list(version_ids)
1559
if None in version_ids:
1560
version_ids.remove(None)
1562
self.source_ancestry = set(self.source.get_ancestry(version_ids))
1563
this_versions = set(self.target._index.get_versions())
1564
needed_versions = self.source_ancestry - this_versions
1565
cross_check_versions = self.source_ancestry.intersection(this_versions)
1566
mismatched_versions = set()
1567
for version in cross_check_versions:
1568
# scan to include needed parents.
1569
n1 = set(self.target.get_parents_with_ghosts(version))
1570
n2 = set(self.source.get_parents_with_ghosts(version))
1572
# FIXME TEST this check for cycles being introduced works
1573
# the logic is we have a cycle if in our graph we are an
1574
# ancestor of any of the n2 revisions.
1580
parent_ancestors = self.source.get_ancestry(parent)
1581
if version in parent_ancestors:
1582
raise errors.GraphCycleError([parent, version])
1583
# ensure this parent will be available later.
1584
new_parents = n2.difference(n1)
1585
needed_versions.update(new_parents.difference(this_versions))
1586
mismatched_versions.add(version)
1588
if not needed_versions and not mismatched_versions:
1590
full_list = topo_sort(self.source.get_graph())
1592
version_list = [i for i in full_list if (not self.target.has_version(i)
1593
and i in needed_versions)]
1597
copy_queue_records = []
1599
for version_id in version_list:
1600
options = self.source._index.get_options(version_id)
1601
parents = self.source._index.get_parents_with_ghosts(version_id)
1602
# check that its will be a consistent copy:
1603
for parent in parents:
1604
# if source has the parent, we must :
1605
# * already have it or
1606
# * have it scheduled already
1607
# otherwise we don't care
1608
assert (self.target.has_version(parent) or
1609
parent in copy_set or
1610
not self.source.has_version(parent))
1611
data_pos, data_size = self.source._index.get_position(version_id)
1612
copy_queue_records.append((version_id, data_pos, data_size))
1613
copy_queue.append((version_id, options, parents))
1614
copy_set.add(version_id)
1616
# data suck the join:
1618
total = len(version_list)
1621
for (version_id, raw_data), \
1622
(version_id2, options, parents) in \
1623
izip(self.source._data.read_records_iter_raw(copy_queue_records),
1625
assert version_id == version_id2, 'logic error, inconsistent results'
1627
pb.update("Joining knit", count, total)
1628
raw_records.append((version_id, options, parents, len(raw_data)))
1629
raw_datum.append(raw_data)
1630
self.target._add_raw_records(raw_records, ''.join(raw_datum))
1632
for version in mismatched_versions:
1633
# FIXME RBC 20060309 is this needed?
1634
n1 = set(self.target.get_parents_with_ghosts(version))
1635
n2 = set(self.source.get_parents_with_ghosts(version))
1636
# write a combined record to our history preserving the current
1637
# parents as first in the list
1638
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
1639
self.target.fix_parents(version, new_parents)
1645
InterVersionedFile.register_optimiser(InterKnit)
1648
class WeaveToKnit(InterVersionedFile):
1649
"""Optimised code paths for weave to knit operations."""
1651
_matching_file_from_factory = bzrlib.weave.WeaveFile
1652
_matching_file_to_factory = KnitVersionedFile
1655
def is_compatible(source, target):
1656
"""Be compatible with weaves to knits."""
1658
return (isinstance(source, bzrlib.weave.Weave) and
1659
isinstance(target, KnitVersionedFile))
1660
except AttributeError:
1663
def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
1664
"""See InterVersionedFile.join."""
1665
assert isinstance(self.source, bzrlib.weave.Weave)
1666
assert isinstance(self.target, KnitVersionedFile)
1668
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
1673
pb = bzrlib.ui.ui_factory.nested_progress_bar()
1675
version_ids = list(version_ids)
1677
self.source_ancestry = set(self.source.get_ancestry(version_ids))
1678
this_versions = set(self.target._index.get_versions())
1679
needed_versions = self.source_ancestry - this_versions
1680
cross_check_versions = self.source_ancestry.intersection(this_versions)
1681
mismatched_versions = set()
1682
for version in cross_check_versions:
1683
# scan to include needed parents.
1684
n1 = set(self.target.get_parents_with_ghosts(version))
1685
n2 = set(self.source.get_parents(version))
1686
# if all of n2's parents are in n1, then its fine.
1687
if n2.difference(n1):
1688
# FIXME TEST this check for cycles being introduced works
1689
# the logic is we have a cycle if in our graph we are an
1690
# ancestor of any of the n2 revisions.
1696
parent_ancestors = self.source.get_ancestry(parent)
1697
if version in parent_ancestors:
1698
raise errors.GraphCycleError([parent, version])
1699
# ensure this parent will be available later.
1700
new_parents = n2.difference(n1)
1701
needed_versions.update(new_parents.difference(this_versions))
1702
mismatched_versions.add(version)
1704
if not needed_versions and not mismatched_versions:
1706
full_list = topo_sort(self.source.get_graph())
1708
version_list = [i for i in full_list if (not self.target.has_version(i)
1709
and i in needed_versions)]
1713
total = len(version_list)
1714
for version_id in version_list:
1715
pb.update("Converting to knit", count, total)
1716
parents = self.source.get_parents(version_id)
1717
# check that its will be a consistent copy:
1718
for parent in parents:
1719
# if source has the parent, we must already have it
1720
assert (self.target.has_version(parent))
1721
self.target.add_lines(
1722
version_id, parents, self.source.get_lines(version_id))
1725
for version in mismatched_versions:
1726
# FIXME RBC 20060309 is this needed?
1727
n1 = set(self.target.get_parents_with_ghosts(version))
1728
n2 = set(self.source.get_parents(version))
1729
# write a combined record to our history preserving the current
1730
# parents as first in the list
1731
new_parents = self.target.get_parents_with_ghosts(version) + list(n2.difference(n1))
1732
self.target.fix_parents(version, new_parents)
1738
InterVersionedFile.register_optimiser(WeaveToKnit)
1741
class KnitSequenceMatcher(difflib.SequenceMatcher):
1742
"""Knit tuned sequence matcher.
1744
This is based on profiling of difflib which indicated some improvements
1745
for our usage pattern.
1748
def find_longest_match(self, alo, ahi, blo, bhi):
1749
"""Find longest matching block in a[alo:ahi] and b[blo:bhi].
1751
If isjunk is not defined:
1753
Return (i,j,k) such that a[i:i+k] is equal to b[j:j+k], where
1754
alo <= i <= i+k <= ahi
1755
blo <= j <= j+k <= bhi
1756
and for all (i',j',k') meeting those conditions,
1759
and if i == i', j <= j'
1761
In other words, of all maximal matching blocks, return one that
1762
starts earliest in a, and of all those maximal matching blocks that
1763
start earliest in a, return the one that starts earliest in b.
1765
>>> s = SequenceMatcher(None, " abcd", "abcd abcd")
1766
>>> s.find_longest_match(0, 5, 0, 9)
1769
If isjunk is defined, first the longest matching block is
1770
determined as above, but with the additional restriction that no
1771
junk element appears in the block. Then that block is extended as
1772
far as possible by matching (only) junk elements on both sides. So
1773
the resulting block never matches on junk except as identical junk
1774
happens to be adjacent to an "interesting" match.
1776
Here's the same example as before, but considering blanks to be
1777
junk. That prevents " abcd" from matching the " abcd" at the tail
1778
end of the second sequence directly. Instead only the "abcd" can
1779
match, and matches the leftmost "abcd" in the second sequence:
1781
>>> s = SequenceMatcher(lambda x: x==" ", " abcd", "abcd abcd")
1782
>>> s.find_longest_match(0, 5, 0, 9)
1785
If no blocks match, return (alo, blo, 0).
1787
>>> s = SequenceMatcher(None, "ab", "c")
1788
>>> s.find_longest_match(0, 2, 0, 1)
1792
# CAUTION: stripping common prefix or suffix would be incorrect.
1796
# Longest matching block is "ab", but if common prefix is
1797
# stripped, it's "a" (tied with "b"). UNIX(tm) diff does so
1798
# strip, so ends up claiming that ab is changed to acab by
1799
# inserting "ca" in the middle. That's minimal but unintuitive:
1800
# "it's obvious" that someone inserted "ac" at the front.
1801
# Windiff ends up at the same place as diff, but by pairing up
1802
# the unique 'b's and then matching the first two 'a's.
1804
a, b, b2j, isbjunk = self.a, self.b, self.b2j, self.isbjunk
1805
besti, bestj, bestsize = alo, blo, 0
1806
# find longest junk-free match
1807
# during an iteration of the loop, j2len[j] = length of longest
1808
# junk-free match ending with a[i-1] and b[j]
1812
for i in xrange(alo, ahi):
1813
# look at all instances of a[i] in b; note that because
1814
# b2j has no junk keys, the loop is skipped if a[i] is junk
1815
j2lenget = j2len.get
1818
# changing b2j.get(a[i], nothing) to a try:KeyError pair produced the
1819
# following improvement
1820
# 704 0 4650.5320 2620.7410 bzrlib.knit:1336(find_longest_match)
1821
# +326674 0 1655.1210 1655.1210 +<method 'get' of 'dict' objects>
1822
# +76519 0 374.6700 374.6700 +<method 'has_key' of 'dict' objects>
1824
# 704 0 3733.2820 2209.6520 bzrlib.knit:1336(find_longest_match)
1825
# +211400 0 1147.3520 1147.3520 +<method 'get' of 'dict' objects>
1826
# +76519 0 376.2780 376.2780 +<method 'has_key' of 'dict' objects>
1838
k = newj2len[j] = 1 + j2lenget(-1 + j, 0)
1840
besti, bestj, bestsize = 1 + i-k, 1 + j-k, k
1843
# Extend the best by non-junk elements on each end. In particular,
1844
# "popular" non-junk elements aren't in b2j, which greatly speeds
1845
# the inner loop above, but also means "the best" match so far
1846
# doesn't contain any junk *or* popular non-junk elements.
1847
while besti > alo and bestj > blo and \
1848
not isbjunk(b[bestj-1]) and \
1849
a[besti-1] == b[bestj-1]:
1850
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
1851
while besti+bestsize < ahi and bestj+bestsize < bhi and \
1852
not isbjunk(b[bestj+bestsize]) and \
1853
a[besti+bestsize] == b[bestj+bestsize]:
1856
# Now that we have a wholly interesting match (albeit possibly
1857
# empty!), we may as well suck up the matching junk on each
1858
# side of it too. Can't think of a good reason not to, and it
1859
# saves post-processing the (possibly considerable) expense of
1860
# figuring out what to do with it. In the case of an empty
1861
# interesting match, this is clearly the right thing to do,
1862
# because no other kind of match is possible in the regions.
1863
while besti > alo and bestj > blo and \
1864
isbjunk(b[bestj-1]) and \
1865
a[besti-1] == b[bestj-1]:
1866
besti, bestj, bestsize = besti-1, bestj-1, bestsize+1
1867
while besti+bestsize < ahi and bestj+bestsize < bhi and \
1868
isbjunk(b[bestj+bestsize]) and \
1869
a[besti+bestsize] == b[bestj+bestsize]:
1870
bestsize = bestsize + 1
1872
return besti, bestj, bestsize
added
removed
bzrlib/knit.py
