Mercurial > hg-stable
view mercurial/changelog.py @ 39877:733db72f0f54
revlog: move revision verification out of verify
File revision verification is performing low-level checks of file
storage, namely that flags are appropriate and revision data can
be resolved.
Since these checks are somewhat revlog-specific and may not
be appropriate for alternate storage backends, this commit moves
those checks from verify.py to revlog.py.
Because we're now emitting warnings/errors that apply to specific
revisions, we taught the iverifyproblem interface to expose the
problematic node and to report this node in verify output. This
was necessary to prevent unwanted test changes.
After this change, revlog.verifyintegrity() and file verify code
in verify.py both iterate over revisions and resolve their fulltext.
But they do so in separate loops. (verify.py needs to resolve
fulltexts as part of calling renamed() - at least when using revlogs.)
This should add overhead.
But on the mozilla-unified repo:
$ hg verify
before: time: real 700.640 secs (user 585.520+0.000 sys 23.480+0.000)
after: time: real 682.380 secs (user 570.370+0.000 sys 22.240+0.000)
I'm not sure what's going on. Maybe avoiding the filelog attribute
proxies shaved off enough time to offset the losses? Maybe fulltext
resolution has less overhead than I thought?
I've left a comment indicating the potential for optimization. But
because it doesn't produce a performance regression on a large
repository, I'm not going to worry about it.
Differential Revision: https://phab.mercurial-scm.org/D4745
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Mon, 24 Sep 2018 11:27:47 -0700 |
parents | b63dee7bd0d9 |
children | a3095bc47217 |
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# changelog.py - changelog class for mercurial # # Copyright 2005-2007 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import from .i18n import _ from .node import ( bin, hex, nullid, ) from .thirdparty import ( attr, ) from . import ( encoding, error, pycompat, revlog, ) from .utils import ( dateutil, stringutil, ) _defaultextra = {'branch': 'default'} def _string_escape(text): """ >>> from .pycompat import bytechr as chr >>> d = {b'nl': chr(10), b'bs': chr(92), b'cr': chr(13), b'nul': chr(0)} >>> s = b"ab%(nl)scd%(bs)s%(bs)sn%(nul)sab%(cr)scd%(bs)s%(nl)s" % d >>> s 'ab\\ncd\\\\\\\\n\\x00ab\\rcd\\\\\\n' >>> res = _string_escape(s) >>> s == stringutil.unescapestr(res) True """ # subset of the string_escape codec text = text.replace('\\', '\\\\').replace('\n', '\\n').replace('\r', '\\r') return text.replace('\0', '\\0') def decodeextra(text): """ >>> from .pycompat import bytechr as chr >>> sorted(decodeextra(encodeextra({b'foo': b'bar', b'baz': chr(0) + b'2'}) ... ).items()) [('baz', '\\x002'), ('branch', 'default'), ('foo', 'bar')] >>> sorted(decodeextra(encodeextra({b'foo': b'bar', ... b'baz': chr(92) + chr(0) + b'2'}) ... ).items()) [('baz', '\\\\\\x002'), ('branch', 'default'), ('foo', 'bar')] """ extra = _defaultextra.copy() for l in text.split('\0'): if l: if '\\0' in l: # fix up \0 without getting into trouble with \\0 l = l.replace('\\\\', '\\\\\n') l = l.replace('\\0', '\0') l = l.replace('\n', '') k, v = stringutil.unescapestr(l).split(':', 1) extra[k] = v return extra def encodeextra(d): # keys must be sorted to produce a deterministic changelog entry items = [_string_escape('%s:%s' % (k, d[k])) for k in sorted(d)] return "\0".join(items) def stripdesc(desc): """strip trailing whitespace and leading and trailing empty lines""" return '\n'.join([l.rstrip() for l in desc.splitlines()]).strip('\n') class appender(object): '''the changelog index must be updated last on disk, so we use this class to delay writes to it''' def __init__(self, vfs, name, mode, buf): self.data = buf fp = vfs(name, mode) self.fp = fp self.offset = fp.tell() self.size = vfs.fstat(fp).st_size self._end = self.size def end(self): return self._end def tell(self): return self.offset def flush(self): pass @property def closed(self): return self.fp.closed def close(self): self.fp.close() def seek(self, offset, whence=0): '''virtual file offset spans real file and data''' if whence == 0: self.offset = offset elif whence == 1: self.offset += offset elif whence == 2: self.offset = self.end() + offset if self.offset < self.size: self.fp.seek(self.offset) def read(self, count=-1): '''only trick here is reads that span real file and data''' ret = "" if self.offset < self.size: s = self.fp.read(count) ret = s self.offset += len(s) if count > 0: count -= len(s) if count != 0: doff = self.offset - self.size self.data.insert(0, "".join(self.data)) del self.data[1:] s = self.data[0][doff:doff + count] self.offset += len(s) ret += s return ret def write(self, s): self.data.append(bytes(s)) self.offset += len(s) self._end += len(s) def __enter__(self): self.fp.__enter__() return self def __exit__(self, *args): return self.fp.__exit__(*args) def _divertopener(opener, target): """build an opener that writes in 'target.a' instead of 'target'""" def _divert(name, mode='r', checkambig=False): if name != target: return opener(name, mode) return opener(name + ".a", mode) return _divert def _delayopener(opener, target, buf): """build an opener that stores chunks in 'buf' instead of 'target'""" def _delay(name, mode='r', checkambig=False): if name != target: return opener(name, mode) return appender(opener, name, mode, buf) return _delay @attr.s class _changelogrevision(object): # Extensions might modify _defaultextra, so let the constructor below pass # it in extra = attr.ib() manifest = attr.ib(default=nullid) user = attr.ib(default='') date = attr.ib(default=(0, 0)) files = attr.ib(default=attr.Factory(list)) description = attr.ib(default='') class changelogrevision(object): """Holds results of a parsed changelog revision. Changelog revisions consist of multiple pieces of data, including the manifest node, user, and date. This object exposes a view into the parsed object. """ __slots__ = ( u'_offsets', u'_text', ) def __new__(cls, text): if not text: return _changelogrevision(extra=_defaultextra) self = super(changelogrevision, cls).__new__(cls) # We could return here and implement the following as an __init__. # But doing it here is equivalent and saves an extra function call. # format used: # nodeid\n : manifest node in ascii # user\n : user, no \n or \r allowed # time tz extra\n : date (time is int or float, timezone is int) # : extra is metadata, encoded and separated by '\0' # : older versions ignore it # files\n\n : files modified by the cset, no \n or \r allowed # (.*) : comment (free text, ideally utf-8) # # changelog v0 doesn't use extra nl1 = text.index('\n') nl2 = text.index('\n', nl1 + 1) nl3 = text.index('\n', nl2 + 1) # The list of files may be empty. Which means nl3 is the first of the # double newline that precedes the description. if text[nl3 + 1:nl3 + 2] == '\n': doublenl = nl3 else: doublenl = text.index('\n\n', nl3 + 1) self._offsets = (nl1, nl2, nl3, doublenl) self._text = text return self @property def manifest(self): return bin(self._text[0:self._offsets[0]]) @property def user(self): off = self._offsets return encoding.tolocal(self._text[off[0] + 1:off[1]]) @property def _rawdate(self): off = self._offsets dateextra = self._text[off[1] + 1:off[2]] return dateextra.split(' ', 2)[0:2] @property def _rawextra(self): off = self._offsets dateextra = self._text[off[1] + 1:off[2]] fields = dateextra.split(' ', 2) if len(fields) != 3: return None return fields[2] @property def date(self): raw = self._rawdate time = float(raw[0]) # Various tools did silly things with the timezone. try: timezone = int(raw[1]) except ValueError: timezone = 0 return time, timezone @property def extra(self): raw = self._rawextra if raw is None: return _defaultextra return decodeextra(raw) @property def files(self): off = self._offsets if off[2] == off[3]: return [] return self._text[off[2] + 1:off[3]].split('\n') @property def description(self): return encoding.tolocal(self._text[self._offsets[3] + 2:]) class changelog(revlog.revlog): def __init__(self, opener, trypending=False): """Load a changelog revlog using an opener. If ``trypending`` is true, we attempt to load the index from a ``00changelog.i.a`` file instead of the default ``00changelog.i``. The ``00changelog.i.a`` file contains index (and possibly inline revision) data for a transaction that hasn't been finalized yet. It exists in a separate file to facilitate readers (such as hooks processes) accessing data before a transaction is finalized. """ if trypending and opener.exists('00changelog.i.a'): indexfile = '00changelog.i.a' else: indexfile = '00changelog.i' datafile = '00changelog.d' revlog.revlog.__init__(self, opener, indexfile, datafile=datafile, checkambig=True, mmaplargeindex=True) if self._initempty: # changelogs don't benefit from generaldelta self.version &= ~revlog.FLAG_GENERALDELTA self._generaldelta = False # Delta chains for changelogs tend to be very small because entries # tend to be small and don't delta well with each. So disable delta # chains. self._storedeltachains = False self._realopener = opener self._delayed = False self._delaybuf = None self._divert = False self.filteredrevs = frozenset() def tiprev(self): for i in pycompat.xrange(len(self) -1, -2, -1): if i not in self.filteredrevs: return i def tip(self): """filtered version of revlog.tip""" return self.node(self.tiprev()) def __contains__(self, rev): """filtered version of revlog.__contains__""" return (0 <= rev < len(self) and rev not in self.filteredrevs) def __iter__(self): """filtered version of revlog.__iter__""" if len(self.filteredrevs) == 0: return revlog.revlog.__iter__(self) def filterediter(): for i in pycompat.xrange(len(self)): if i not in self.filteredrevs: yield i return filterediter() def revs(self, start=0, stop=None): """filtered version of revlog.revs""" for i in super(changelog, self).revs(start, stop): if i not in self.filteredrevs: yield i def reachableroots(self, minroot, heads, roots, includepath=False): return self.index.reachableroots2(minroot, heads, roots, includepath) def headrevs(self): if self.filteredrevs: try: return self.index.headrevsfiltered(self.filteredrevs) # AttributeError covers non-c-extension environments and # old c extensions without filter handling. except AttributeError: return self._headrevs() return super(changelog, self).headrevs() def strip(self, *args, **kwargs): # XXX make something better than assert # We can't expect proper strip behavior if we are filtered. assert not self.filteredrevs super(changelog, self).strip(*args, **kwargs) def rev(self, node): """filtered version of revlog.rev""" r = super(changelog, self).rev(node) if r in self.filteredrevs: raise error.FilteredLookupError(hex(node), self.indexfile, _('filtered node')) return r def node(self, rev): """filtered version of revlog.node""" if rev in self.filteredrevs: raise error.FilteredIndexError(rev) return super(changelog, self).node(rev) def linkrev(self, rev): """filtered version of revlog.linkrev""" if rev in self.filteredrevs: raise error.FilteredIndexError(rev) return super(changelog, self).linkrev(rev) def parentrevs(self, rev): """filtered version of revlog.parentrevs""" if rev in self.filteredrevs: raise error.FilteredIndexError(rev) return super(changelog, self).parentrevs(rev) def flags(self, rev): """filtered version of revlog.flags""" if rev in self.filteredrevs: raise error.FilteredIndexError(rev) return super(changelog, self).flags(rev) def delayupdate(self, tr): "delay visibility of index updates to other readers" if not self._delayed: if len(self) == 0: self._divert = True if self._realopener.exists(self.indexfile + '.a'): self._realopener.unlink(self.indexfile + '.a') self.opener = _divertopener(self._realopener, self.indexfile) else: self._delaybuf = [] self.opener = _delayopener(self._realopener, self.indexfile, self._delaybuf) self._delayed = True tr.addpending('cl-%i' % id(self), self._writepending) tr.addfinalize('cl-%i' % id(self), self._finalize) def _finalize(self, tr): "finalize index updates" self._delayed = False self.opener = self._realopener # move redirected index data back into place if self._divert: assert not self._delaybuf tmpname = self.indexfile + ".a" nfile = self.opener.open(tmpname) nfile.close() self.opener.rename(tmpname, self.indexfile, checkambig=True) elif self._delaybuf: fp = self.opener(self.indexfile, 'a', checkambig=True) fp.write("".join(self._delaybuf)) fp.close() self._delaybuf = None self._divert = False # split when we're done self._enforceinlinesize(tr) def _writepending(self, tr): "create a file containing the unfinalized state for pretxnchangegroup" if self._delaybuf: # make a temporary copy of the index fp1 = self._realopener(self.indexfile) pendingfilename = self.indexfile + ".a" # register as a temp file to ensure cleanup on failure tr.registertmp(pendingfilename) # write existing data fp2 = self._realopener(pendingfilename, "w") fp2.write(fp1.read()) # add pending data fp2.write("".join(self._delaybuf)) fp2.close() # switch modes so finalize can simply rename self._delaybuf = None self._divert = True self.opener = _divertopener(self._realopener, self.indexfile) if self._divert: return True return False def _enforceinlinesize(self, tr, fp=None): if not self._delayed: revlog.revlog._enforceinlinesize(self, tr, fp) def read(self, node): """Obtain data from a parsed changelog revision. Returns a 6-tuple of: - manifest node in binary - author/user as a localstr - date as a 2-tuple of (time, timezone) - list of files - commit message as a localstr - dict of extra metadata Unless you need to access all fields, consider calling ``changelogrevision`` instead, as it is faster for partial object access. """ c = changelogrevision(self.revision(node)) return ( c.manifest, c.user, c.date, c.files, c.description, c.extra ) def changelogrevision(self, nodeorrev): """Obtain a ``changelogrevision`` for a node or revision.""" return changelogrevision(self.revision(nodeorrev)) def readfiles(self, node): """ short version of read that only returns the files modified by the cset """ text = self.revision(node) if not text: return [] last = text.index("\n\n") l = text[:last].split('\n') return l[3:] def add(self, manifest, files, desc, transaction, p1, p2, user, date=None, extra=None): # Convert to UTF-8 encoded bytestrings as the very first # thing: calling any method on a localstr object will turn it # into a str object and the cached UTF-8 string is thus lost. user, desc = encoding.fromlocal(user), encoding.fromlocal(desc) user = user.strip() # An empty username or a username with a "\n" will make the # revision text contain two "\n\n" sequences -> corrupt # repository since read cannot unpack the revision. if not user: raise error.StorageError(_("empty username")) if "\n" in user: raise error.StorageError(_("username %r contains a newline") % pycompat.bytestr(user)) desc = stripdesc(desc) if date: parseddate = "%d %d" % dateutil.parsedate(date) else: parseddate = "%d %d" % dateutil.makedate() if extra: branch = extra.get("branch") if branch in ("default", ""): del extra["branch"] elif branch in (".", "null", "tip"): raise error.StorageError(_('the name \'%s\' is reserved') % branch) if extra: extra = encodeextra(extra) parseddate = "%s %s" % (parseddate, extra) l = [hex(manifest), user, parseddate] + sorted(files) + ["", desc] text = "\n".join(l) return self.addrevision(text, transaction, len(self), p1, p2) def branchinfo(self, rev): """return the branch name and open/close state of a revision This function exists because creating a changectx object just to access this is costly.""" extra = self.read(rev)[5] return encoding.tolocal(extra.get("branch")), 'close' in extra