--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/revlogutils/censor.py Sat May 29 00:11:56 2021 +0200
@@ -0,0 +1,102 @@
+# censor code related to censoring revision
+#
+# Copyright 2021 Pierre-Yves David <pierre-yves.david@octobus.net>
+# Copyright 2015 Google, Inc <martinvonz@google.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 ..node import (
+ nullrev,
+)
+from ..i18n import _
+from .. import (
+ error,
+)
+from ..utils import (
+ storageutil,
+)
+from . import constants
+
+
+def v1_censor(rl, tr, censornode, tombstone=b''):
+ """censors a revision in a "version 1" revlog"""
+ assert rl._format_version == constants.REVLOGV1, rl._format_version
+
+ # avoid cycle
+ from .. import revlog
+
+ censorrev = rl.rev(censornode)
+ tombstone = storageutil.packmeta({b'censored': tombstone}, b'')
+
+ if len(tombstone) > rl.rawsize(censorrev):
+ raise error.Abort(
+ _(b'censor tombstone must be no longer than censored data')
+ )
+
+ # Rewriting the revlog in place is hard. Our strategy for censoring is
+ # to create a new revlog, copy all revisions to it, then replace the
+ # revlogs on transaction close.
+ #
+ # This is a bit dangerous. We could easily have a mismatch of state.
+ newrl = revlog.revlog(
+ rl.opener,
+ target=rl.target,
+ radix=rl.radix,
+ postfix=b'tmpcensored',
+ censorable=True,
+ )
+ newrl._format_version = rl._format_version
+ newrl._format_flags = rl._format_flags
+ newrl._generaldelta = rl._generaldelta
+ newrl._parse_index = rl._parse_index
+
+ for rev in rl.revs():
+ node = rl.node(rev)
+ p1, p2 = rl.parents(node)
+
+ if rev == censorrev:
+ newrl.addrawrevision(
+ tombstone,
+ tr,
+ rl.linkrev(censorrev),
+ p1,
+ p2,
+ censornode,
+ constants.REVIDX_ISCENSORED,
+ )
+
+ if newrl.deltaparent(rev) != nullrev:
+ m = _(b'censored revision stored as delta; cannot censor')
+ h = _(
+ b'censoring of revlogs is not fully implemented;'
+ b' please report this bug'
+ )
+ raise error.Abort(m, hint=h)
+ continue
+
+ if rl.iscensored(rev):
+ if rl.deltaparent(rev) != nullrev:
+ m = _(
+ b'cannot censor due to censored '
+ b'revision having delta stored'
+ )
+ raise error.Abort(m)
+ rawtext = rl._chunk(rev)
+ else:
+ rawtext = rl.rawdata(rev)
+
+ newrl.addrawrevision(
+ rawtext, tr, rl.linkrev(rev), p1, p2, node, rl.flags(rev)
+ )
+
+ tr.addbackup(rl._indexfile, location=b'store')
+ if not rl._inline:
+ tr.addbackup(rl._datafile, location=b'store')
+
+ rl.opener.rename(newrl._indexfile, rl._indexfile)
+ if not rl._inline:
+ rl.opener.rename(newrl._datafile, rl._datafile)
+
+ rl.clearcaches()
+ rl._loadindex()