Mercurial > hg
view mercurial/repair.py @ 26755:bb0b955d050d
streamclone: support for producing and consuming stream clone bundles
Up to this point, stream clones only existed as a dynamically generated
data format produced and consumed during streaming clones. In order to
support this efficient cloning format with the clone bundles feature, we
need a more formal, on disk representation of the streaming clone data.
This patch introduces a new "bundle" type for streaming clones. Unlike
existing bundles, it does not contain changegroup data. It does,
however, share the same concepts like the 4 byte header which identifies
the type of data that follows and the 2 byte abbreviation for
compression types (of which only "UN" is currently supported).
The new bundle format is essentially the existing stream clone version 1
data format with some headers at the beginning.
Content negotiation at stream clone request time checked for repository
format/requirements compatibility before initiating a stream clone. We
can't do active content negotiation when using clone bundles. So, we put
this set of requirements inside the payload so consumers have a built-in
mechanism for checking compatibility before reading and applying lots of
data. Of course, we will also advertise this requirements set in clone
bundles. But that's for another patch.
We currently don't have a mechanism to produce and consume this new
bundle format. This will be implemented in upcoming patches.
It's worth noting that if a legacy client attempts to `hg unbundle` a
stream clone bundle (with the "HGS1" header), it will abort with:
"unknown bundle version S1," which seems appropriate.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sat, 17 Oct 2015 11:14:52 -0700 |
parents | b1a0c534d9b4 |
children | 75d550b7d8f5 |
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# repair.py - functions for repository repair for mercurial # # Copyright 2005, 2006 Chris Mason <mason@suse.com> # Copyright 2007 Matt Mackall # # 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 import errno from .i18n import _ from .node import short from . import ( bundle2, changegroup, error, exchange, util, ) def _bundle(repo, bases, heads, node, suffix, compress=True): """create a bundle with the specified revisions as a backup""" cgversion = '01' if 'generaldelta' in repo.requirements: cgversion = '02' cg = changegroup.changegroupsubset(repo, bases, heads, 'strip', version=cgversion) backupdir = "strip-backup" vfs = repo.vfs if not vfs.isdir(backupdir): vfs.mkdir(backupdir) # Include a hash of all the nodes in the filename for uniqueness allcommits = repo.set('%ln::%ln', bases, heads) allhashes = sorted(c.hex() for c in allcommits) totalhash = util.sha1(''.join(allhashes)).hexdigest() name = "%s/%s-%s-%s.hg" % (backupdir, short(node), totalhash[:8], suffix) comp = None if cgversion != '01': bundletype = "HG20" if compress: comp = 'BZ' elif compress: bundletype = "HG10BZ" else: bundletype = "HG10UN" return changegroup.writebundle(repo.ui, cg, name, bundletype, vfs, compression=comp) def _collectfiles(repo, striprev): """find out the filelogs affected by the strip""" files = set() for x in xrange(striprev, len(repo)): files.update(repo[x].files()) return sorted(files) def _collectbrokencsets(repo, files, striprev): """return the changesets which will be broken by the truncation""" s = set() def collectone(revlog): _, brokenset = revlog.getstrippoint(striprev) s.update([revlog.linkrev(r) for r in brokenset]) collectone(repo.manifest) for fname in files: collectone(repo.file(fname)) return s def strip(ui, repo, nodelist, backup=True, topic='backup'): # Simple way to maintain backwards compatibility for this # argument. if backup in ['none', 'strip']: backup = False repo = repo.unfiltered() repo.destroying() cl = repo.changelog # TODO handle undo of merge sets if isinstance(nodelist, str): nodelist = [nodelist] striplist = [cl.rev(node) for node in nodelist] striprev = min(striplist) # Some revisions with rev > striprev may not be descendants of striprev. # We have to find these revisions and put them in a bundle, so that # we can restore them after the truncations. # To create the bundle we use repo.changegroupsubset which requires # the list of heads and bases of the set of interesting revisions. # (head = revision in the set that has no descendant in the set; # base = revision in the set that has no ancestor in the set) tostrip = set(striplist) for rev in striplist: for desc in cl.descendants([rev]): tostrip.add(desc) files = _collectfiles(repo, striprev) saverevs = _collectbrokencsets(repo, files, striprev) # compute heads saveheads = set(saverevs) for r in xrange(striprev + 1, len(cl)): if r not in tostrip: saverevs.add(r) saveheads.difference_update(cl.parentrevs(r)) saveheads.add(r) saveheads = [cl.node(r) for r in saveheads] # compute base nodes if saverevs: descendants = set(cl.descendants(saverevs)) saverevs.difference_update(descendants) savebases = [cl.node(r) for r in saverevs] stripbases = [cl.node(r) for r in tostrip] # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), but # is much faster newbmtarget = repo.revs('max(parents(%ld) - (%ld))', tostrip, tostrip) if newbmtarget: newbmtarget = repo[newbmtarget.first()].node() else: newbmtarget = '.' bm = repo._bookmarks updatebm = [] for m in bm: rev = repo[bm[m]].rev() if rev in tostrip: updatebm.append(m) # create a changegroup for all the branches we need to keep backupfile = None vfs = repo.vfs node = nodelist[-1] if backup: backupfile = _bundle(repo, stripbases, cl.heads(), node, topic) repo.ui.status(_("saved backup bundle to %s\n") % vfs.join(backupfile)) repo.ui.log("backupbundle", "saved backup bundle to %s\n", vfs.join(backupfile)) if saveheads or savebases: # do not compress partial bundle if we remove it from disk later chgrpfile = _bundle(repo, savebases, saveheads, node, 'temp', compress=False) mfst = repo.manifest curtr = repo.currenttransaction() if curtr is not None: del curtr # avoid carrying reference to transaction for nothing msg = _('programming error: cannot strip from inside a transaction') raise error.Abort(msg, hint=_('contact your extension maintainer')) tr = repo.transaction("strip") offset = len(tr.entries) try: tr.startgroup() cl.strip(striprev, tr) mfst.strip(striprev, tr) for fn in files: repo.file(fn).strip(striprev, tr) tr.endgroup() try: for i in xrange(offset, len(tr.entries)): file, troffset, ignore = tr.entries[i] repo.svfs(file, 'a').truncate(troffset) if troffset == 0: repo.store.markremoved(file) tr.close() finally: tr.release() if saveheads or savebases: ui.note(_("adding branch\n")) f = vfs.open(chgrpfile, "rb") gen = exchange.readbundle(ui, f, chgrpfile, vfs) if not repo.ui.verbose: # silence internal shuffling chatter repo.ui.pushbuffer() if isinstance(gen, bundle2.unbundle20): tr = repo.transaction('strip') tr.hookargs = {'source': 'strip', 'url': 'bundle:' + vfs.join(chgrpfile)} try: bundle2.processbundle(repo, gen, lambda: tr) tr.close() finally: tr.release() else: gen.apply(repo, 'strip', 'bundle:' + vfs.join(chgrpfile), True) if not repo.ui.verbose: repo.ui.popbuffer() f.close() # remove undo files for undovfs, undofile in repo.undofiles(): try: undovfs.unlink(undofile) except OSError as e: if e.errno != errno.ENOENT: ui.warn(_('error removing %s: %s\n') % (undovfs.join(undofile), str(e))) for m in updatebm: bm[m] = repo[newbmtarget].node() bm.write() except: # re-raises if backupfile: ui.warn(_("strip failed, full bundle stored in '%s'\n") % vfs.join(backupfile)) elif saveheads: ui.warn(_("strip failed, partial bundle stored in '%s'\n") % vfs.join(chgrpfile)) raise else: if saveheads or savebases: # Remove partial backup only if there were no exceptions vfs.unlink(chgrpfile) repo.destroyed() def rebuildfncache(ui, repo): """Rebuilds the fncache file from repo history. Missing entries will be added. Extra entries will be removed. """ repo = repo.unfiltered() if 'fncache' not in repo.requirements: ui.warn(_('(not rebuilding fncache because repository does not ' 'support fncache)\n')) return lock = repo.lock() try: fnc = repo.store.fncache # Trigger load of fncache. if 'irrelevant' in fnc: pass oldentries = set(fnc.entries) newentries = set() seenfiles = set() repolen = len(repo) for rev in repo: ui.progress(_('changeset'), rev, total=repolen) ctx = repo[rev] for f in ctx.files(): # This is to minimize I/O. if f in seenfiles: continue seenfiles.add(f) i = 'data/%s.i' % f d = 'data/%s.d' % f if repo.store._exists(i): newentries.add(i) if repo.store._exists(d): newentries.add(d) ui.progress(_('changeset'), None) addcount = len(newentries - oldentries) removecount = len(oldentries - newentries) for p in sorted(oldentries - newentries): ui.write(_('removing %s\n') % p) for p in sorted(newentries - oldentries): ui.write(_('adding %s\n') % p) if addcount or removecount: ui.write(_('%d items added, %d removed from fncache\n') % (addcount, removecount)) fnc.entries = newentries fnc._dirty = True tr = repo.transaction('fncache') try: fnc.write(tr) tr.close() finally: tr.release() else: ui.write(_('fncache already up to date\n')) finally: lock.release() def stripbmrevset(repo, mark): """ The revset to strip when strip is called with -B mark Needs to live here so extensions can use it and wrap it even when strip is not enabled or not present on a box. """ return repo.revs("ancestors(bookmark(%s)) - " "ancestors(head() and not bookmark(%s)) - " "ancestors(bookmark() and not bookmark(%s))", mark, mark, mark)