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Diffstat (limited to 'mercurial/obsolete.py')
| -rw-r--r-- | mercurial/obsolete.py | 331 |
1 files changed, 0 insertions, 331 deletions
diff --git a/mercurial/obsolete.py b/mercurial/obsolete.py deleted file mode 100644 index aea116d..0000000 --- a/mercurial/obsolete.py +++ /dev/null @@ -1,331 +0,0 @@ -# obsolete.py - obsolete markers handling -# -# Copyright 2012 Pierre-Yves David <pierre-yves.david@ens-lyon.org> -# Logilab SA <contact@logilab.fr> -# -# This software may be used and distributed according to the terms of the -# GNU General Public License version 2 or any later version. - -"""Obsolete markers handling - -An obsolete marker maps an old changeset to a list of new -changesets. If the list of new changesets is empty, the old changeset -is said to be "killed". Otherwise, the old changeset is being -"replaced" by the new changesets. - -Obsolete markers can be used to record and distribute changeset graph -transformations performed by history rewriting operations, and help -building new tools to reconciliate conflicting rewriting actions. To -facilitate conflicts resolution, markers include various annotations -besides old and news changeset identifiers, such as creation date or -author name. - - -Format ------- - -Markers are stored in an append-only file stored in -'.hg/store/obsstore'. - -The file starts with a version header: - -- 1 unsigned byte: version number, starting at zero. - - -The header is followed by the markers. Each marker is made of: - -- 1 unsigned byte: number of new changesets "R", could be zero. - -- 1 unsigned 32-bits integer: metadata size "M" in bytes. - -- 1 byte: a bit field. It is reserved for flags used in obsolete - markers common operations, to avoid repeated decoding of metadata - entries. - -- 20 bytes: obsoleted changeset identifier. - -- N*20 bytes: new changesets identifiers. - -- M bytes: metadata as a sequence of nul-terminated strings. Each - string contains a key and a value, separated by a color ':', without - additional encoding. Keys cannot contain '\0' or ':' and values - cannot contain '\0'. -""" -import struct -from mercurial import util, base85 -from i18n import _ - -# the obsolete feature is not mature enought to be enabled by default. -# you have to rely on third party extension extension to enable this. -_enabled = False - -_pack = struct.pack -_unpack = struct.unpack - -# the obsolete feature is not mature enought to be enabled by default. -# you have to rely on third party extension extension to enable this. -_enabled = False - -# data used for parsing and writing -_fmversion = 0 -_fmfixed = '>BIB20s' -_fmnode = '20s' -_fmfsize = struct.calcsize(_fmfixed) -_fnodesize = struct.calcsize(_fmnode) - -def _readmarkers(data): - """Read and enumerate markers from raw data""" - off = 0 - diskversion = _unpack('>B', data[off:off + 1])[0] - off += 1 - if diskversion != _fmversion: - raise util.Abort(_('parsing obsolete marker: unknown version %r') - % diskversion) - - # Loop on markers - l = len(data) - while off + _fmfsize <= l: - # read fixed part - cur = data[off:off + _fmfsize] - off += _fmfsize - nbsuc, mdsize, flags, pre = _unpack(_fmfixed, cur) - # read replacement - sucs = () - if nbsuc: - s = (_fnodesize * nbsuc) - cur = data[off:off + s] - sucs = _unpack(_fmnode * nbsuc, cur) - off += s - # read metadata - # (metadata will be decoded on demand) - metadata = data[off:off + mdsize] - if len(metadata) != mdsize: - raise util.Abort(_('parsing obsolete marker: metadata is too ' - 'short, %d bytes expected, got %d') - % (mdsize, len(metadata))) - off += mdsize - yield (pre, sucs, flags, metadata) - -def encodemeta(meta): - """Return encoded metadata string to string mapping. - - Assume no ':' in key and no '\0' in both key and value.""" - for key, value in meta.iteritems(): - if ':' in key or '\0' in key: - raise ValueError("':' and '\0' are forbidden in metadata key'") - if '\0' in value: - raise ValueError("':' are forbidden in metadata value'") - return '\0'.join(['%s:%s' % (k, meta[k]) for k in sorted(meta)]) - -def decodemeta(data): - """Return string to string dictionary from encoded version.""" - d = {} - for l in data.split('\0'): - if l: - key, value = l.split(':') - d[key] = value - return d - -class marker(object): - """Wrap obsolete marker raw data""" - - def __init__(self, repo, data): - # the repo argument will be used to create changectx in later version - self._repo = repo - self._data = data - self._decodedmeta = None - - def precnode(self): - """Precursor changeset node identifier""" - return self._data[0] - - def succnodes(self): - """List of successor changesets node identifiers""" - return self._data[1] - - def metadata(self): - """Decoded metadata dictionary""" - if self._decodedmeta is None: - self._decodedmeta = decodemeta(self._data[3]) - return self._decodedmeta - - def date(self): - """Creation date as (unixtime, offset)""" - parts = self.metadata()['date'].split(' ') - return (float(parts[0]), int(parts[1])) - -class obsstore(object): - """Store obsolete markers - - Markers can be accessed with two mappings: - - precursors: old -> set(new) - - successors: new -> set(old) - """ - - def __init__(self, sopener): - self._all = [] - # new markers to serialize - self.precursors = {} - self.successors = {} - self.sopener = sopener - data = sopener.tryread('obsstore') - if data: - self._load(_readmarkers(data)) - - def __iter__(self): - return iter(self._all) - - def __nonzero__(self): - return bool(self._all) - - def create(self, transaction, prec, succs=(), flag=0, metadata=None): - """obsolete: add a new obsolete marker - - * ensuring it is hashable - * check mandatory metadata - * encode metadata - """ - if metadata is None: - metadata = {} - if len(prec) != 20: - raise ValueError(prec) - for succ in succs: - if len(succ) != 20: - raise ValueError(succ) - marker = (str(prec), tuple(succs), int(flag), encodemeta(metadata)) - self.add(transaction, [marker]) - - def add(self, transaction, markers): - """Add new markers to the store - - Take care of filtering duplicate. - Return the number of new marker.""" - if not _enabled: - raise util.Abort('obsolete feature is not enabled on this repo') - new = [m for m in markers if m not in self._all] - if new: - f = self.sopener('obsstore', 'ab') - try: - # Whether the file's current position is at the begin or at - # the end after opening a file for appending is implementation - # defined. So we must seek to the end before calling tell(), - # or we may get a zero offset for non-zero sized files on - # some platforms (issue3543). - f.seek(0, 2) # os.SEEK_END - offset = f.tell() - transaction.add('obsstore', offset) - # offset == 0: new file - add the version header - for bytes in _encodemarkers(new, offset == 0): - f.write(bytes) - finally: - # XXX: f.close() == filecache invalidation == obsstore rebuilt. - # call 'filecacheentry.refresh()' here - f.close() - self._load(new) - return len(new) - - def mergemarkers(self, transation, data): - markers = _readmarkers(data) - self.add(transation, markers) - - def _load(self, markers): - for mark in markers: - self._all.append(mark) - pre, sucs = mark[:2] - self.precursors.setdefault(pre, set()).add(mark) - for suc in sucs: - self.successors.setdefault(suc, set()).add(mark) - -def _encodemarkers(markers, addheader=False): - # Kept separate from flushmarkers(), it will be reused for - # markers exchange. - if addheader: - yield _pack('>B', _fmversion) - for marker in markers: - yield _encodeonemarker(marker) - - -def _encodeonemarker(marker): - pre, sucs, flags, metadata = marker - nbsuc = len(sucs) - format = _fmfixed + (_fmnode * nbsuc) - data = [nbsuc, len(metadata), flags, pre] - data.extend(sucs) - return _pack(format, *data) + metadata - -# arbitrary picked to fit into 8K limit from HTTP server -# you have to take in account: -# - the version header -# - the base85 encoding -_maxpayload = 5300 - -def listmarkers(repo): - """List markers over pushkey""" - if not repo.obsstore: - return {} - keys = {} - parts = [] - currentlen = _maxpayload * 2 # ensure we create a new part - for marker in repo.obsstore: - nextdata = _encodeonemarker(marker) - if (len(nextdata) + currentlen > _maxpayload): - currentpart = [] - currentlen = 0 - parts.append(currentpart) - currentpart.append(nextdata) - currentlen += len(nextdata) - for idx, part in enumerate(reversed(parts)): - data = ''.join([_pack('>B', _fmversion)] + part) - keys['dump%i' % idx] = base85.b85encode(data) - return keys - -def pushmarker(repo, key, old, new): - """Push markers over pushkey""" - if not key.startswith('dump'): - repo.ui.warn(_('unknown key: %r') % key) - return 0 - if old: - repo.ui.warn(_('unexpected old value') % key) - return 0 - data = base85.b85decode(new) - lock = repo.lock() - try: - tr = repo.transaction('pushkey: obsolete markers') - try: - repo.obsstore.mergemarkers(tr, data) - tr.close() - return 1 - finally: - tr.release() - finally: - lock.release() - -def allmarkers(repo): - """all obsolete markers known in a repository""" - for markerdata in repo.obsstore: - yield marker(repo, markerdata) - -def precursormarkers(ctx): - """obsolete marker making this changeset obsolete""" - for data in ctx._repo.obsstore.precursors.get(ctx.node(), ()): - yield marker(ctx._repo, data) - -def successormarkers(ctx): - """obsolete marker marking this changeset as a successors""" - for data in ctx._repo.obsstore.successors.get(ctx.node(), ()): - yield marker(ctx._repo, data) - -def anysuccessors(obsstore, node): - """Yield every successor of <node> - - This this a linear yield unsuitable to detect splitted changeset.""" - remaining = set([node]) - seen = set(remaining) - while remaining: - current = remaining.pop() - yield current - for mark in obsstore.precursors.get(current, ()): - for suc in mark[1]: - if suc not in seen: - seen.add(suc) - remaining.add(suc) |