plan9fox/sys/lib/python/mercurial/repair.py
2011-05-03 11:25:13 +00:00

146 lines
4.8 KiB
Python

# 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, incorporated herein by reference.
import changegroup
from node import nullrev, short
from i18n import _
import os
def _bundle(repo, bases, heads, node, suffix, extranodes=None):
"""create a bundle with the specified revisions as a backup"""
cg = repo.changegroupsubset(bases, heads, 'strip', extranodes)
backupdir = repo.join("strip-backup")
if not os.path.isdir(backupdir):
os.mkdir(backupdir)
name = os.path.join(backupdir, "%s-%s" % (short(node), suffix))
repo.ui.warn(_("saving bundle to %s\n") % name)
return changegroup.writebundle(cg, name, "HG10BZ")
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 _collectextranodes(repo, files, link):
"""return the nodes that have to be saved before the strip"""
def collectone(revlog):
extra = []
startrev = count = len(revlog)
# find the truncation point of the revlog
for i in xrange(count):
lrev = revlog.linkrev(i)
if lrev >= link:
startrev = i + 1
break
# see if any revision after that point has a linkrev less than link
# (we have to manually save these guys)
for i in xrange(startrev, count):
node = revlog.node(i)
lrev = revlog.linkrev(i)
if lrev < link:
extra.append((node, cl.node(lrev)))
return extra
extranodes = {}
cl = repo.changelog
extra = collectone(repo.manifest)
if extra:
extranodes[1] = extra
for fname in files:
f = repo.file(fname)
extra = collectone(f)
if extra:
extranodes[fname] = extra
return extranodes
def strip(ui, repo, node, backup="all"):
cl = repo.changelog
# TODO delete the undo files, and handle undo of merge sets
striprev = cl.rev(node)
# 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((striprev,))
saveheads = set()
savebases = []
for r in xrange(striprev + 1, len(cl)):
parents = cl.parentrevs(r)
if parents[0] in tostrip or parents[1] in tostrip:
# r is a descendant of striprev
tostrip.add(r)
# if this is a merge and one of the parents does not descend
# from striprev, mark that parent as a savehead.
if parents[1] != nullrev:
for p in parents:
if p not in tostrip and p > striprev:
saveheads.add(p)
else:
# if no parents of this revision will be stripped, mark it as
# a savebase
if parents[0] < striprev and parents[1] < striprev:
savebases.append(cl.node(r))
saveheads.difference_update(parents)
saveheads.add(r)
saveheads = [cl.node(r) for r in saveheads]
files = _collectfiles(repo, striprev)
extranodes = _collectextranodes(repo, files, striprev)
# create a changegroup for all the branches we need to keep
if backup == "all":
_bundle(repo, [node], cl.heads(), node, 'backup')
if saveheads or extranodes:
chgrpfile = _bundle(repo, savebases, saveheads, node, 'temp',
extranodes)
mfst = repo.manifest
tr = repo.transaction()
offset = len(tr.entries)
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)
tr.close()
except:
tr.abort()
raise
if saveheads or extranodes:
ui.status(_("adding branch\n"))
f = open(chgrpfile, "rb")
gen = changegroup.readbundle(f, chgrpfile)
repo.addchangegroup(gen, 'strip', 'bundle:' + chgrpfile, True)
f.close()
if backup != "strip":
os.unlink(chgrpfile)
repo.destroyed()