Mercurial > hg
view tests/test-import-bypass.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 | 8d72e29ad1e0 |
children | 6a454e7053a1 |
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$ echo "[extensions]" >> $HGRCPATH $ echo "purge=" >> $HGRCPATH $ shortlog() { > hg log -G --template '{rev}:{node|short} {author} {date|hgdate} - {branch} - {desc|firstline}\n' > } Test --bypass with other options $ hg init repo-options $ cd repo-options $ echo a > a $ hg ci -Am adda adding a $ echo a >> a $ hg branch foo marked working directory as branch foo (branches are permanent and global, did you want a bookmark?) $ hg ci -Am changea $ hg export . > ../test.diff $ hg up null 0 files updated, 0 files merged, 1 files removed, 0 files unresolved Test importing an existing revision (this also tests that "hg import" disallows combination of '--exact' and '--edit') $ hg import --bypass --exact --edit ../test.diff abort: cannot specify both --exact and --edit [10] $ hg import --bypass --exact ../test.diff applying ../test.diff $ shortlog o 1:4e322f7ce8e3 test 0 0 - foo - changea | o 0:07f494440405 test 0 0 - default - adda Test failure without --exact $ hg import --bypass ../test.diff applying ../test.diff unable to find 'a' for patching (use '--prefix' to apply patch relative to the current directory) abort: patch failed to apply [255] $ hg st $ shortlog o 1:4e322f7ce8e3 test 0 0 - foo - changea | o 0:07f494440405 test 0 0 - default - adda Test --user, --date and --message $ hg up 0 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg import --bypass --u test2 -d '1 0' -m patch2 ../test.diff applying ../test.diff $ cat .hg/last-message.txt patch2 (no-eol) $ shortlog o 2:2e127d1da504 test2 1 0 - default - patch2 | | o 1:4e322f7ce8e3 test 0 0 - foo - changea |/ @ 0:07f494440405 test 0 0 - default - adda $ hg rollback repository tip rolled back to revision 1 (undo import) Test --import-branch (this also tests that editor is not invoked for '--bypass', if the patch contains the commit message, regardless of '--edit') $ HGEDITOR=cat hg import --bypass --import-branch --edit ../test.diff applying ../test.diff $ shortlog o 1:4e322f7ce8e3 test 0 0 - foo - changea | @ 0:07f494440405 test 0 0 - default - adda $ hg rollback repository tip rolled back to revision 1 (undo import) Test --strip $ hg import --bypass --strip 0 - <<EOF > # HG changeset patch > # User test > # Date 0 0 > # Branch foo > # Node ID 4e322f7ce8e3e4203950eac9ece27bf7e45ffa6c > # Parent 07f4944404050f47db2e5c5071e0e84e7a27bba9 > changea > > diff -r 07f494440405 -r 4e322f7ce8e3 a > --- a Thu Jan 01 00:00:00 1970 +0000 > +++ a Thu Jan 01 00:00:00 1970 +0000 > @@ -1,1 +1,2 @@ > a > +a > EOF applying patch from stdin $ hg rollback repository tip rolled back to revision 1 (undo import) Test --strip with --bypass $ mkdir -p dir/dir2 $ echo bb > dir/dir2/b $ echo cc > dir/dir2/c $ echo d > dir/d $ hg ci -Am 'addabcd' adding dir/d adding dir/dir2/b adding dir/dir2/c $ shortlog @ 2:d805bc8236b6 test 0 0 - default - addabcd | | o 1:4e322f7ce8e3 test 0 0 - foo - changea |/ o 0:07f494440405 test 0 0 - default - adda $ hg import --bypass --strip 2 --prefix dir/ - <<EOF > # HG changeset patch > # User test > # Date 0 0 > # Branch foo > changeabcd > > diff --git a/foo/a b/foo/a > new file mode 100644 > --- /dev/null > +++ b/foo/a > @@ -0,0 +1 @@ > +a > diff --git a/foo/dir2/b b/foo/dir2/b2 > rename from foo/dir2/b > rename to foo/dir2/b2 > diff --git a/foo/dir2/c b/foo/dir2/c > --- a/foo/dir2/c > +++ b/foo/dir2/c > @@ -0,0 +1 @@ > +cc > diff --git a/foo/d b/foo/d > deleted file mode 100644 > --- a/foo/d > +++ /dev/null > @@ -1,1 +0,0 @@ > -d > EOF applying patch from stdin $ shortlog o 3:5bd46886ca3e test 0 0 - default - changeabcd | @ 2:d805bc8236b6 test 0 0 - default - addabcd | | o 1:4e322f7ce8e3 test 0 0 - foo - changea |/ o 0:07f494440405 test 0 0 - default - adda $ hg diff --change 3 --git diff --git a/dir/a b/dir/a new file mode 100644 --- /dev/null +++ b/dir/a @@ -0,0 +1,1 @@ +a diff --git a/dir/d b/dir/d deleted file mode 100644 --- a/dir/d +++ /dev/null @@ -1,1 +0,0 @@ -d diff --git a/dir/dir2/b b/dir/dir2/b2 rename from dir/dir2/b rename to dir/dir2/b2 diff --git a/dir/dir2/c b/dir/dir2/c --- a/dir/dir2/c +++ b/dir/dir2/c @@ -1,1 +1,2 @@ cc +cc $ hg -q --config extensions.strip= strip . Test unsupported combinations $ hg import --bypass --no-commit ../test.diff abort: cannot specify both --no-commit and --bypass [10] $ hg import --bypass --similarity 50 ../test.diff abort: cannot use --similarity with --bypass [10] $ hg import --exact --prefix dir/ ../test.diff abort: cannot specify both --exact and --prefix [10] Test commit editor (this also tests that editor is invoked, if the patch doesn't contain the commit message, regardless of '--edit') $ cat > ../test.diff <<EOF > diff -r 07f494440405 -r 4e322f7ce8e3 a > --- a/a Thu Jan 01 00:00:00 1970 +0000 > +++ b/a Thu Jan 01 00:00:00 1970 +0000 > @@ -1,1 +1,2 @@ > -a > +b > +c > EOF $ HGEDITOR=cat hg import --bypass ../test.diff applying ../test.diff HG: Enter commit message. Lines beginning with 'HG:' are removed. HG: Leave message empty to abort commit. HG: -- HG: user: test HG: branch 'default' HG: changed a abort: empty commit message [10] Test patch.eol is handled (this also tests that editor is not invoked for '--bypass', if the commit message is explicitly specified, regardless of '--edit') $ "$PYTHON" -c 'open("a", "wb").write(b"a\r\n")' $ hg ci -m makeacrlf $ HGEDITOR=cat hg import -m 'should fail because of eol' --edit --bypass ../test.diff applying ../test.diff patching file a Hunk #1 FAILED at 0 abort: patch failed to apply [255] $ hg --config patch.eol=auto import -d '0 0' -m 'test patch.eol' --bypass ../test.diff applying ../test.diff $ shortlog o 3:c606edafba99 test 0 0 - default - test patch.eol | @ 2:872023de769d test 0 0 - default - makeacrlf | | o 1:4e322f7ce8e3 test 0 0 - foo - changea |/ o 0:07f494440405 test 0 0 - default - adda Test applying multiple patches $ hg up -qC 0 $ echo e > e $ hg ci -Am adde adding e created new head $ hg export . > ../patch1.diff $ hg up -qC 1 $ echo f > f $ hg ci -Am addf adding f $ hg export . > ../patch2.diff $ cd .. $ hg clone -r1 repo-options repo-multi1 adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets 07f494440405:4e322f7ce8e3 updating to branch foo 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd repo-multi1 $ hg up 0 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg import --bypass ../patch1.diff ../patch2.diff applying ../patch1.diff applying ../patch2.diff $ shortlog o 3:bc8ca3f8a7c4 test 0 0 - default - addf | o 2:16581080145e test 0 0 - default - adde | | o 1:4e322f7ce8e3 test 0 0 - foo - changea |/ @ 0:07f494440405 test 0 0 - default - adda Test applying multiple patches with --exact $ cd .. $ hg clone -r1 repo-options repo-multi2 adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets 07f494440405:4e322f7ce8e3 updating to branch foo 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd repo-multi2 $ hg import --bypass --exact ../patch1.diff ../patch2.diff applying ../patch1.diff applying ../patch2.diff $ shortlog o 3:d60cb8989666 test 0 0 - foo - addf | | o 2:16581080145e test 0 0 - default - adde | | @ | 1:4e322f7ce8e3 test 0 0 - foo - changea |/ o 0:07f494440405 test 0 0 - default - adda $ cd .. Test avoiding editor invocation at applying the patch with --exact even if commit message is empty $ cd repo-options $ echo a >> a $ hg commit -m ' ' $ hg tip -T "{node}\n" 1b77bc7d1db9f0e7f1716d515b630516ab386c89 $ hg export -o ../empty-log.diff . $ hg update -q -C ".^1" $ hg --config extensions.strip= strip -q tip $ HGEDITOR=cat hg import --exact --bypass ../empty-log.diff applying ../empty-log.diff $ hg tip -T "{node}\n" 1b77bc7d1db9f0e7f1716d515b630516ab386c89 $ cd .. #if symlink execbit Test complicated patch with --exact $ hg init repo-exact $ cd repo-exact $ echo a > a $ echo c > c $ echo d > d $ echo e > e $ echo f > f $ chmod +x f $ ln -s c linkc $ hg ci -Am t adding a adding c adding d adding e adding f adding linkc $ hg cp a aa1 $ echo b >> a $ echo b > b $ hg add b $ hg cp a aa2 $ echo aa >> aa2 $ chmod +x e $ chmod -x f $ ln -s a linka $ hg rm d $ hg rm linkc $ hg mv c cc $ hg ci -m patch $ hg export --git . > ../test.diff $ hg up -C null 0 files updated, 0 files merged, 7 files removed, 0 files unresolved $ hg purge $ hg st $ hg import --bypass --exact ../test.diff applying ../test.diff The patch should have matched the exported revision and generated no additional data. If not, diff both heads to debug it. $ shortlog o 1:2978fd5c8aa4 test 0 0 - default - patch | o 0:a0e19e636a43 test 0 0 - default - t #endif $ cd ..