Mercurial > hg
view tests/test-bundle-r.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 | 17a695357270 |
children | 6fc57680cfd6 |
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$ hg init test $ cd test $ hg unbundle "$TESTDIR/bundles/remote.hg" adding changesets adding manifests adding file changes added 9 changesets with 7 changes to 4 files (+1 heads) new changesets bfaf4b5cbf01:916f1afdef90 (9 drafts) (run 'hg heads' to see heads, 'hg merge' to merge) $ hg up tip 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd .. $ for i in 0 1 2 3 4 5 6 7 8; do > mkdir test-"$i" > hg --cwd test-"$i" init > hg -R test bundle -r "$i" test-"$i".hg test-"$i" > cd test-"$i" > hg unbundle ../test-"$i".hg > hg verify > hg tip -q > cd .. > done searching for changes 1 changesets found adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files new changesets bfaf4b5cbf01 (1 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 1 changesets with 1 changes to 1 files 0:bfaf4b5cbf01 searching for changes 2 changesets found adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets bfaf4b5cbf01:21f32785131f (2 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 2 changesets with 2 changes to 1 files 1:21f32785131f searching for changes 3 changesets found adding changesets adding manifests adding file changes added 3 changesets with 3 changes to 1 files new changesets bfaf4b5cbf01:4ce51a113780 (3 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 3 changesets with 3 changes to 1 files 2:4ce51a113780 searching for changes 4 changesets found adding changesets adding manifests adding file changes added 4 changesets with 4 changes to 1 files new changesets bfaf4b5cbf01:93ee6ab32777 (4 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 4 changesets with 4 changes to 1 files 3:93ee6ab32777 searching for changes 2 changesets found adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets bfaf4b5cbf01:c70afb1ee985 (2 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 2 changesets with 2 changes to 1 files 1:c70afb1ee985 searching for changes 3 changesets found adding changesets adding manifests adding file changes added 3 changesets with 3 changes to 1 files new changesets bfaf4b5cbf01:f03ae5a9b979 (3 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 3 changesets with 3 changes to 1 files 2:f03ae5a9b979 searching for changes 4 changesets found adding changesets adding manifests adding file changes added 4 changesets with 5 changes to 2 files new changesets bfaf4b5cbf01:095cb14b1b4d (4 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 4 changesets with 5 changes to 2 files 3:095cb14b1b4d searching for changes 5 changesets found adding changesets adding manifests adding file changes added 5 changesets with 6 changes to 3 files new changesets bfaf4b5cbf01:faa2e4234c7a (5 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 5 changesets with 6 changes to 3 files 4:faa2e4234c7a searching for changes 5 changesets found adding changesets adding manifests adding file changes added 5 changesets with 5 changes to 2 files new changesets bfaf4b5cbf01:916f1afdef90 (5 drafts) (run 'hg update' to get a working copy) checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 5 changesets with 5 changes to 2 files 4:916f1afdef90 $ cd test-8 $ hg pull ../test-7 pulling from ../test-7 searching for changes adding changesets adding manifests adding file changes added 4 changesets with 2 changes to 3 files (+1 heads) new changesets c70afb1ee985:faa2e4234c7a 1 local changesets published (run 'hg heads' to see heads, 'hg merge' to merge) $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 9 changesets with 7 changes to 4 files $ hg rollback repository tip rolled back to revision 4 (undo pull) $ cd .. should fail $ hg -R test bundle --base 2 -r tip test-bundle-branch1.hg test-3 abort: --base is incompatible with specifying a destination [10] $ hg -R test bundle -a -r tip test-bundle-branch1.hg test-3 abort: --all is incompatible with specifying a destination [10] $ hg -R test bundle -r tip test-bundle-branch1.hg abort: repository default-push not found [255] $ hg -R test bundle --base 2 -r tip test-bundle-branch1.hg 2 changesets found $ hg -R test bundle --base 2 -r 7 test-bundle-branch2.hg 4 changesets found $ hg -R test bundle --base 2 test-bundle-all.hg 6 changesets found $ hg -R test bundle --base 2 --all test-bundle-all-2.hg ignoring --base because --all was specified 9 changesets found $ hg -R test bundle --base 3 -r tip test-bundle-should-fail.hg 1 changesets found empty bundle $ hg -R test bundle --base 7 --base 8 test-bundle-empty.hg no changes found [1] issue76 msg2163 $ hg -R test bundle --base 3 -r 3 -r 3 test-bundle-cset-3.hg no changes found [1] Issue1910: 'hg bundle --base $head' does not exclude $head from result $ hg -R test bundle --base 7 test-bundle-cset-7.hg 4 changesets found $ hg clone test-2 test-9 updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd test-9 revision 2 $ hg tip -q 2:4ce51a113780 $ hg unbundle ../test-bundle-should-fail.hg adding changesets transaction abort! rollback completed abort: 00changelog.i@93ee6ab32777: unknown parent [50] revision 2 $ hg tip -q 2:4ce51a113780 $ hg unbundle ../test-bundle-all.hg adding changesets adding manifests adding file changes added 6 changesets with 4 changes to 4 files (+1 heads) new changesets 93ee6ab32777:916f1afdef90 (6 drafts) (run 'hg heads' to see heads, 'hg merge' to merge) revision 8 $ hg tip -q 8:916f1afdef90 $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 9 changesets with 7 changes to 4 files $ hg rollback repository tip rolled back to revision 2 (undo unbundle) revision 2 $ hg tip -q 2:4ce51a113780 $ hg unbundle ../test-bundle-branch1.hg adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 2 files new changesets 93ee6ab32777:916f1afdef90 (2 drafts) (run 'hg update' to get a working copy) revision 4 $ hg tip -q 4:916f1afdef90 $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 5 changesets with 5 changes to 2 files $ hg rollback repository tip rolled back to revision 2 (undo unbundle) $ hg unbundle ../test-bundle-branch2.hg adding changesets adding manifests adding file changes added 4 changesets with 3 changes to 3 files (+1 heads) new changesets c70afb1ee985:faa2e4234c7a (4 drafts) (run 'hg heads' to see heads, 'hg merge' to merge) revision 6 $ hg tip -q 6:faa2e4234c7a $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 7 changesets with 6 changes to 3 files $ hg rollback repository tip rolled back to revision 2 (undo unbundle) $ hg unbundle ../test-bundle-cset-7.hg adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 2 files new changesets 93ee6ab32777:916f1afdef90 (2 drafts) (run 'hg update' to get a working copy) revision 4 $ hg tip -q 4:916f1afdef90 $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 5 changesets with 5 changes to 2 files $ cd ../test $ hg merge 7 note: possible conflict - afile was renamed multiple times to: adifferentfile anotherfile 2 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg ci -m merge $ cd .. $ hg -R test bundle --base 2 test-bundle-head.hg 7 changesets found $ hg clone test-2 test-10 updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd test-10 $ hg unbundle ../test-bundle-head.hg adding changesets adding manifests adding file changes added 7 changesets with 4 changes to 4 files new changesets 93ee6ab32777:03fc0b0e347c (7 drafts) (run 'hg update' to get a working copy) revision 9 $ hg tip -q 9:03fc0b0e347c $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 10 changesets with 7 changes to 4 files $ cd ..