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Differential D10458

nodemap: deal with data mmap error
ClosedPublic

Authored by marmoute on Apr 16 2021, 12:08 PM.

Details

Reviewers
pulkit
Group Reviewers
hg-reviewers
Commits
rHGa3720569a43f: nodemap: deal with data mmap error
Summary

If the file is too small, the mmapread call would raise a ValueError. We catch
that and ignore nodemap content (as we do without mmap). This make the repository
slightly slower (until the next write) but usable. Unlike the current crash.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

marmoute created this revision.Apr 16 2021, 12:08 PM
pulkit accepted this revision.Apr 17 2021, 4:47 PM
This revision is now accepted and ready to land.Apr 17 2021, 4:47 PM
marmoute added a commit: rHGa3720569a43f: nodemap: deal with data mmap error.Apr 17 2021, 6:13 PM
Closed by commit rHGa3720569a43f: nodemap: deal with data mmap error (authored by marmoute). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

Diff 27003

mercurial/revlogutils/nodemap.py

docket.data_length = data_length docket.data_length = data_length
docket.data_unused = data_unused docket.data_unused = data_unused
filename = _rawdata_filepath(revlog, docket) filename = _rawdata_filepath(revlog, docket)
use_mmap = revlog.opener.options.get(b"persistent-nodemap.mmap") use_mmap = revlog.opener.options.get(b"persistent-nodemap.mmap")
try: try:
with revlog.opener(filename) as fd: with revlog.opener(filename) as fd:
if use_mmap: if use_mmap:
try:
data = util.buffer(util.mmapread(fd, data_length)) data = util.buffer(util.mmapread(fd, data_length))
except ValueError:
# raised when the read file is too small
data = b''
else: else:
data = fd.read(data_length) data = fd.read(data_length)
except (IOError, OSError) as e: except (IOError, OSError) as e:
if e.errno == errno.ENOENT: if e.errno == errno.ENOENT:
return None return None
else: else:
raise raise
if len(data) < data_length: if len(data) < data_length:

tests/test-persistent-nodemap.t

corruption-test-repo/.hg/store/00changelog-*.nd: size=121088 (glob) corruption-test-repo/.hg/store/00changelog-*.nd: size=121088 (glob)
$ dd if=$datafilepath bs=1000 count=10 of=$datafilepath-tmp status=none $ dd if=$datafilepath bs=1000 count=10 of=$datafilepath-tmp status=none
$ mv $datafilepath-tmp $datafilepath $ mv $datafilepath-tmp $datafilepath
$ f -s $datafilepath $ f -s $datafilepath
corruption-test-repo/.hg/store/00changelog-*.nd: size=10000 (glob) corruption-test-repo/.hg/store/00changelog-*.nd: size=10000 (glob)
Check that Mercurial reaction to this event Check that Mercurial reaction to this event
$ hg -R corruption-test-repo log -r . $ hg -R corruption-test-repo log -r . --traceback
abort: index 00changelog.i is corrupted changeset: 5005:90d5d3ba2fc4
[50] tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a2
stream clone stream clone
------------ ------------
The persistent nodemap should exist after a streaming clone The persistent nodemap should exist after a streaming clone
$ hg clone -U --stream --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" ssh://user@dummy/test-repo stream-clone --debug | egrep '00(changelog|manifest)' $ hg clone -U --stream --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" ssh://user@dummy/test-repo stream-clone --debug | egrep '00(changelog|manifest)'