mercurial/repair.py
author FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
Thu, 26 Feb 2015 06:03:39 +0900
branchstable
changeset 24158 d414c28db84d
parent 23939 33d1b81c6ef0
child 24170 fbc4d550a6ab
permissions -rw-r--r--
largefiles: access to specific fields only if largefiles enabled (issue4547) Even if largefiles extension is enabled in a repository, "repo" object, which isn't "largefiles.reposetup()"-ed, is passed to overridden functions in the cases below unexpectedly, because extensions are enabled for each repositories strictly. (1) clone without -U: (2) pull with -U: (3) pull with --rebase: combination of "enabled@src", "disabled@dst" and "not-required@src" cause this situation. largefiles requirement @src @dst @src result -------- -------- --------------- -------------------- enabled disabled not-required aborted unexpectedly required requirement error (intentional) -------- -------- --------------- -------------------- enabled enabled * success -------- -------- --------------- -------------------- disabled enabled * success (only for "pull") -------- -------- --------------- -------------------- disabled disabled not-required success required requirement error (intentional) -------- -------- --------------- -------------------- (4) update/revert with a subrepo disabling largefiles In these cases, overridden functions cause accessing to largefiles specific fields of not "largefiles.reposetup()"-ed "repo" object, and execution is aborted. - (1), (2), (4) cause accessing to "_lfstatuswriters" in "getstatuswriter()" invoked via "updatelfiles()" - (3) causes accessing to "_lfcommithooks" in "overriderebase()" For safe accessing to these fields, this patch examines whether passed "repo" object is "largefiles.reposetup()"-ed or not before accessing to them. This patch chooses examining existence of newly introduced "_largefilesenabled" instead of "_lfcommithooks" and "_lfstatuswriters" directly, because the former is better name for the generic "largefiles is enabled in this repo" mark than the latter. In the future, all other overridden functions should avoid largefiles specific processing for efficiency, and "_largefilesenabled" is better also for such purpose. BTW, "lfstatus" can't be used for such purpose, because some code paths set it forcibly regardless of existence of it in specified "repo" object.

# 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, util, bundle2
from mercurial.node import short, hex
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"""
    usebundle2 = (repo.ui.config('experimental', 'bundle2-exp') and
                  repo.ui.config('experimental', 'strip-bundle2-version'))
    if usebundle2:
        cgversion = repo.ui.config('experimental', 'strip-bundle2-version')
        if cgversion not in changegroup.packermap:
            repo.ui.warn(_('unknown strip-bundle2-version value %r; ' +
                            'should be one of %r\n') %
                         (cgversion, sorted(changegroup.packermap.keys()),))
            cgversion = '01'
            usebundle2 = False
    else:
        cgversion = '01'

    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
    hexbases = (hex(n) for n in bases)
    hexheads = (hex(n) for n in heads)
    allcommits = repo.set('%ls::%ls', hexbases, hexheads)
    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)

    if usebundle2:
        bundletype = "HG2Y"
    elif compress:
        bundletype = "HG10BZ"
    else:
        bundletype = "HG10UN"
    return changegroup.writebundle(repo.ui, 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.svfs(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()
            if isinstance(gen, bundle2.unbundle20):
                tr = repo.transaction('strip')
                try:
                    bundle2.processbundle(repo, gen, lambda: tr)
                    tr.close()
                finally:
                    tr.release()
            else:
                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()