Mercurial > hg
view tests/test-narrow-clone.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 | 6cc269bd1c29 |
| children | 84a93fa7ecfd |
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$ . "$TESTDIR/narrow-library.sh" $ hg init master $ cd master $ cat >> .hg/hgrc <<EOF > [narrow] > serveellipses=True > EOF $ mkdir dir $ mkdir dir/src $ cd dir/src $ for x in `$TESTDIR/seq.py 20`; do echo $x > "f$x"; hg add "f$x"; hg commit -m "Commit src $x"; done $ cd .. $ mkdir tests $ cd tests $ for x in `$TESTDIR/seq.py 20`; do echo $x > "t$x"; hg add "t$x"; hg commit -m "Commit test $x"; done $ cd ../../.. Only path: and rootfilesin: pattern prefixes are allowed $ hg clone --narrow ssh://user@dummy/master badnarrow --noupdate --include 'glob:**' abort: invalid prefix on narrow pattern: glob:** (narrow patterns must begin with one of the following: path:, rootfilesin:) [255] $ hg clone --narrow ssh://user@dummy/master badnarrow --noupdate --exclude 'set:ignored' abort: invalid prefix on narrow pattern: set:ignored (narrow patterns must begin with one of the following: path:, rootfilesin:) [255] narrow clone a file, f10 $ hg clone --narrow ssh://user@dummy/master narrow --noupdate --include "dir/src/f10" requesting all changes adding changesets adding manifests adding file changes added 3 changesets with 1 changes to 1 files new changesets *:* (glob) $ cd narrow $ cat .hg/requires | grep -v generaldelta dotencode fncache narrowhg-experimental revlogv1 sparserevlog store testonly-simplestore (reposimplestore !) $ hg tracked I path:dir/src/f10 $ hg tracked I path:dir/src/f10 $ hg update 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/src dir/src/f10 $ cat dir/src/f10 10 $ cd .. BUG: local-to-local narrow clones should work, but don't. $ hg clone --narrow master narrow-via-localpeer --noupdate --include "dir/src/f10" requesting all changes abort: server does not support narrow clones [255] $ hg tracked -R narrow-via-localpeer abort: repository narrow-via-localpeer not found [255] $ rm -Rf narrow-via-localpeer narrow clone with a newline should fail $ hg clone --narrow ssh://user@dummy/master narrow_fail --noupdate --include 'dir/src/f10 > ' abort: newlines are not allowed in narrowspec paths [255] narrow clone a directory, tests/, except tests/t19 $ hg clone --narrow ssh://user@dummy/master narrowdir --noupdate --include "dir/tests/" --exclude "dir/tests/t19" requesting all changes adding changesets adding manifests adding file changes added 21 changesets with 19 changes to 19 files new changesets *:* (glob) $ cd narrowdir $ hg tracked I path:dir/tests X path:dir/tests/t19 $ hg tracked I path:dir/tests X path:dir/tests/t19 $ hg update 19 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/tests dir/tests/t1 dir/tests/t10 dir/tests/t11 dir/tests/t12 dir/tests/t13 dir/tests/t14 dir/tests/t15 dir/tests/t16 dir/tests/t17 dir/tests/t18 dir/tests/t2 dir/tests/t20 dir/tests/t3 dir/tests/t4 dir/tests/t5 dir/tests/t6 dir/tests/t7 dir/tests/t8 dir/tests/t9 $ cd .. narrow clone everything but a directory (tests/) $ hg clone --narrow ssh://user@dummy/master narrowroot --noupdate --exclude "dir/tests" requesting all changes adding changesets adding manifests adding file changes added 21 changesets with 20 changes to 20 files new changesets *:* (glob) $ cd narrowroot $ hg tracked I path:. X path:dir/tests $ hg tracked I path:. X path:dir/tests $ hg update 20 files updated, 0 files merged, 0 files removed, 0 files unresolved $ find * | sort dir dir/src dir/src/f1 dir/src/f10 dir/src/f11 dir/src/f12 dir/src/f13 dir/src/f14 dir/src/f15 dir/src/f16 dir/src/f17 dir/src/f18 dir/src/f19 dir/src/f2 dir/src/f20 dir/src/f3 dir/src/f4 dir/src/f5 dir/src/f6 dir/src/f7 dir/src/f8 dir/src/f9 $ cd .. narrow clone no paths at all $ hg clone --narrow ssh://user@dummy/master narrowempty --noupdate requesting all changes adding changesets adding manifests adding file changes added 1 changesets with 0 changes to 0 files new changesets * (glob) $ cd narrowempty $ hg tracked $ hg update 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ ls -A .hg $ cd .. simple clone $ hg clone ssh://user@dummy/master simpleclone requesting all changes adding changesets adding manifests adding file changes added 40 changesets with 40 changes to 40 files new changesets * (glob) updating to branch default 40 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd simpleclone $ find * | sort dir dir/src dir/src/f1 dir/src/f10 dir/src/f11 dir/src/f12 dir/src/f13 dir/src/f14 dir/src/f15 dir/src/f16 dir/src/f17 dir/src/f18 dir/src/f19 dir/src/f2 dir/src/f20 dir/src/f3 dir/src/f4 dir/src/f5 dir/src/f6 dir/src/f7 dir/src/f8 dir/src/f9 dir/tests dir/tests/t1 dir/tests/t10 dir/tests/t11 dir/tests/t12 dir/tests/t13 dir/tests/t14 dir/tests/t15 dir/tests/t16 dir/tests/t17 dir/tests/t18 dir/tests/t19 dir/tests/t2 dir/tests/t20 dir/tests/t3 dir/tests/t4 dir/tests/t5 dir/tests/t6 dir/tests/t7 dir/tests/t8 dir/tests/t9 $ cd .. Testing the --narrowspec flag to clone $ cat >> narrowspecs <<EOF > %include foo > [include] > path:dir/tests/ > path:dir/src/f12 > EOF $ hg clone ssh://user@dummy/master specfile --narrowspec narrowspecs reading narrowspec from '$TESTTMP/narrowspecs' config error: cannot specify other files using '%include' in narrowspec [30] $ cat > narrowspecs <<EOF > [include] > path:dir/tests/ > path:dir/src/f12 > EOF $ hg clone ssh://user@dummy/master specfile --narrowspec narrowspecs reading narrowspec from '$TESTTMP/narrowspecs' requesting all changes adding changesets adding manifests adding file changes added 23 changesets with 21 changes to 21 files new changesets c13e3773edb4:26ce255d5b5d updating to branch default 21 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd specfile $ hg tracked I path:dir/src/f12 I path:dir/tests $ cd .. Narrow spec with invalid patterns is rejected $ cat > narrowspecs <<EOF > [include] > glob:** > EOF $ hg clone ssh://user@dummy/master badspecfile --narrowspec narrowspecs reading narrowspec from '$TESTTMP/narrowspecs' abort: invalid prefix on narrow pattern: glob:** (narrow patterns must begin with one of the following: path:, rootfilesin:) [255]