Mercurial > hg
view tests/test-encoding.t @ 46607:e9901d01d135
revlog: add a mechanism to verify expected file position before appending
If someone uses `hg debuglocks`, or some non-hg process writes to the .hg
directory without respecting the locks, or if the repo's on a networked
filesystem, it's possible for the revlog code to write out corrupted data.
The form of this corruption can vary depending on what data was written and how
that happened. We are in the "networked filesystem" case (though I've had users
also do this to themselves with the "`hg debuglocks`" scenario), and most often
see this with the changelog. What ends up happening is we produce two items
(let's call them rev1 and rev2) in the .i file that have the same linkrev,
baserev, and offset into the .d file, while the data in the .d file is appended
properly. rev2's compressed_size is accurate for rev2, but when we go to
decompress the data in the .d file, we use the offset that's recorded in the
index file, which is the same as rev1, and attempt to decompress
rev2.compressed_size bytes of rev1's data. This usually does not succeed. :)
When using inline data, this also fails, though I haven't investigated why too
closely. This shows up as a "patch decode" error. I believe what's happening
there is that we're basically ignoring the offset field, getting the data
properly, but since baserev != rev, it thinks this is a delta based on rev
(instead of a full text) and can't actually apply it as such.
For now, I'm going to make this an optional component and default it to entirely
off. I may increase the default severity of this in the future, once I've
enabled it for my users and we gain more experience with it. Luckily, most of my
users have a versioned filesystem and can roll back to before the corruption has
been written, it's just a hassle to do so and not everyone knows how (so it's a
support burden). Users on other filesystems will not have that luxury, and this
can cause them to have a corrupted repository that they are unlikely to know how
to resolve, and they'll see this as a data-loss event. Refusing to create the
corruption is a much better user experience.
This mechanism is not perfect. There may be false-negatives (racy writes that
are not detected). There should not be any false-positives (non-racy writes that
are detected as such). This is not a mechanism that makes putting a repo on a
networked filesystem "safe" or "supported", just *less* likely to cause
corruption.
Differential Revision: https://phab.mercurial-scm.org/D9952
author | Kyle Lippincott <spectral@google.com> |
---|---|
date | Wed, 03 Feb 2021 16:33:10 -0800 |
parents | ef6cab7930b3 |
children |
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Test character encoding $ hg init t $ cd t we need a repo with some legacy latin-1 changesets $ hg unbundle "$TESTDIR/bundles/legacy-encoding.hg" adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets 1e78a93102a3:0e5b7e3f9c4a (2 drafts) (run 'hg update' to get a working copy) $ hg co 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ "$PYTHON" << EOF > f = open('latin-1', 'wb'); f.write(b"latin-1 e' encoded: \xe9"); f.close() > f = open('utf-8', 'wb'); f.write(b"utf-8 e' encoded: \xc3\xa9"); f.close() > f = open('latin-1-tag', 'wb'); f.write(b"\xe9"); f.close() > EOF should fail with encoding error $ echo "plain old ascii" > a $ hg st M a ? latin-1 ? latin-1-tag ? utf-8 $ HGENCODING=ascii hg ci -l latin-1 transaction abort! rollback completed abort: decoding near ' encoded: \xe9': 'ascii' codec can't decode byte 0xe9 in position 20: ordinal not in range(128)! (esc) [255] these should work $ echo "latin-1" > a $ HGENCODING=latin-1 hg ci -l latin-1 $ echo "utf-8" > a $ HGENCODING=utf-8 hg ci -l utf-8 $ HGENCODING=latin-1 hg tag `cat latin-1-tag` $ HGENCODING=latin-1 hg branch `cat latin-1-tag` marked working directory as branch \xe9 (esc) (branches are permanent and global, did you want a bookmark?) $ HGENCODING=latin-1 hg ci -m 'latin1 branch' $ hg -q rollback $ HGENCODING=latin-1 hg branch \xe9 (esc) $ HGENCODING=latin-1 hg ci -m 'latin1 branch' $ rm .hg/branch hg log (ascii) $ hg --encoding ascii log changeset: 5:a52c0692f24a branch: ? tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag ? for changeset ca661e7520de changeset: 3:ca661e7520de tag: ? user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: ? changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: ? changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: ????? = u'\u0440\u0442\u0443\u0442\u044c' changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': ? = u'\xe9' hg log (latin-1) $ hg --encoding latin-1 log changeset: 5:a52c0692f24a branch: \xe9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xe9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xe9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xe9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xe9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xd2\xd4\xd5\xd4\xd8 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xe9 = u'\\xe9' (esc) hg log (utf-8) $ hg --encoding utf-8 log changeset: 5:a52c0692f24a branch: \xc3\xa9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xc3\xa9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xc3\xa9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xc3\xa9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xc3\xa9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xc3\x92\xc3\x94\xc3\x95\xc3\x94\xc3\x98 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xc3\xa9 = u'\\xe9' (esc) hg tags (ascii) $ HGENCODING=ascii hg tags tip 5:a52c0692f24a ? 3:ca661e7520de hg tags (latin-1) $ HGENCODING=latin-1 hg tags tip 5:a52c0692f24a \xe9 3:ca661e7520de (esc) hg tags (utf-8) $ HGENCODING=utf-8 hg tags tip 5:a52c0692f24a \xc3\xa9 3:ca661e7520de (esc) hg tags (JSON) $ hg tags -Tjson [ { "node": "a52c0692f24ad921c0a31e1736e7635a8b23b670", "rev": 5, "tag": "tip", "type": "" }, { "node": "ca661e7520dec3f5438a63590c350bebadb04989", "rev": 3, "tag": "\xc3\xa9", (esc) "type": "" } ] hg branches (ascii) $ HGENCODING=ascii hg branches ? 5:a52c0692f24a default 4:94db611b4196 (inactive) hg branches (latin-1) $ HGENCODING=latin-1 hg branches \xe9 5:a52c0692f24a (esc) default 4:94db611b4196 (inactive) hg branches (utf-8) $ HGENCODING=utf-8 hg branches \xc3\xa9 5:a52c0692f24a (esc) default 4:94db611b4196 (inactive) $ echo '[ui]' >> .hg/hgrc $ echo 'fallbackencoding = koi8-r' >> .hg/hgrc hg log (utf-8) $ HGENCODING=utf-8 hg log changeset: 5:a52c0692f24a branch: \xc3\xa9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xc3\xa9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xc3\xa9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xc3\xa9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xc3\xa9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xd1\x80\xd1\x82\xd1\x83\xd1\x82\xd1\x8c = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xd0\x98 = u'\\xe9' (esc) hg log (dolphin) $ HGENCODING=dolphin hg log abort: unknown encoding: dolphin (please check your locale settings) [255] $ HGENCODING=ascii hg branch `cat latin-1-tag` abort: decoding near '\xe9': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)! (esc) [255] $ cp latin-1-tag .hg/branch $ HGENCODING=latin-1 hg ci -m 'auto-promote legacy name' Test roundtrip encoding of lookup tables when not using UTF-8 (issue2763) $ HGENCODING=latin-1 hg up `cat latin-1-tag` 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ cd .. Test roundtrip encoding/decoding of utf8b for generated data #if hypothesis >>> import hypothesishelpers >>> from mercurial import encoding >>> hypothesishelpers.roundtrips(hypothesishelpers.st.binary(), ... encoding.fromutf8b, encoding.toutf8b) Round trip OK #endif