bundle2-push: provide transaction to reply unbundler
This patch series is intended to allow bundle2 push reply part handlers to
make changes to the local repository; it has been developed in parallel with
an extension that allows the server to rebase incoming changesets while applying
them.
This diff adds an experimental config option "bundle2.pushback" which provides
a transaction to the reply unbundler during a push operation. This behavior is
opt-in because of potential security issues: the response can contain any part
type that has a handler defined, allowing the server to make arbitrary changes
to the local repository.
# 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 mercurial import changegroup, exchange
from mercurial.node import short
from mercurial.i18n import _
import errno
def _bundle(repo, bases, heads, node, suffix, compress=True):
"""create a bundle with the specified revisions as a backup"""
cg = changegroup.changegroupsubset(repo, bases, heads, 'strip')
backupdir = "strip-backup"
vfs = repo.vfs
if not vfs.isdir(backupdir):
vfs.mkdir(backupdir)
name = "%s/%s-%s.hg" % (backupdir, short(node), suffix)
if compress:
bundletype = "HG10BZ"
else:
bundletype = "HG10UN"
return changegroup.writebundle(cg, name, bundletype, vfs)
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
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
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.sopener(file, 'a').truncate(troffset)
if troffset == 0:
repo.store.markremoved(file)
tr.close()
except: # re-raises
tr.abort()
raise
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()
changegroup.addchangegroup(repo, gen, '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, 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()