rust-revlog: fix RevlogEntry.data() for NULL_REVISION
Before this change, the pseudo-entry returned by `Revlog.get_entry` for
`NULL_REVISION` would trigger errors in application code using it.
For example, this fixes a crash spotted with changelog data
while implementing RHGitaly: `Changelog.data_for_rev(-1)` was already
returning the pseudo content as expected, e.g., for `hg log`, but
`Changelog.entry_for_rev(-1).data()` would still crash with
"corrupted revlog, hash check failed for revision -1". There is
an added test for this scenario.
Test correctness of revlog inline -> non-inline transition
----------------------------------------------------------
We test various file length and naming pattern as this created issue in the
past.
Helper extension to intercept renames and kill process
$ cat > $TESTTMP/intercept_before_rename.py << EOF
> import os
> import signal
> from mercurial import extensions, util
>
> def extsetup(ui):
> def rename(orig, src, dest, *args, **kwargs):
> path = util.normpath(dest)
> if path.endswith(b'data/file.i'):
> os.kill(os.getpid(), signal.SIGKILL)
> return orig(src, dest, *args, **kwargs)
> extensions.wrapfunction(util, 'rename', rename)
> EOF
$ cat > $TESTTMP/intercept_after_rename.py << EOF
> import os
> import signal
> from mercurial import extensions, util
>
> def extsetup(ui):
> def close(orig, *args, **kwargs):
> path = util.normpath(args[0]._atomictempfile__name)
> r = orig(*args, **kwargs)
> if path.endswith(b'/.hg/store/data/file.i'):
> os.kill(os.getpid(), signal.SIGKILL)
> return r
> extensions.wrapfunction(util.atomictempfile, 'close', close)
> def extsetup(ui):
> def rename(orig, src, dest, *args, **kwargs):
> path = util.normpath(dest)
> r = orig(src, dest, *args, **kwargs)
> if path.endswith(b'data/file.i'):
> os.kill(os.getpid(), signal.SIGKILL)
> return r
> extensions.wrapfunction(util, 'rename', rename)
> EOF
$ cat > $TESTTMP/killme.py << EOF
> import os
> import signal
>
> def killme(ui, repo, hooktype, **kwargs):
> os.kill(os.getpid(), signal.SIGKILL)
> EOF
$ cat > $TESTTMP/reader_wait_split.py << EOF
> import os
> import signal
> from mercurial import extensions, revlog, testing
> def _wait_post_load(orig, self, *args, **kwargs):
> wait = b'data/file' in self.radix
> if wait:
> testing.wait_file(b"$TESTTMP/writer-revlog-split")
> r = orig(self, *args, **kwargs)
> if wait:
> testing.write_file(b"$TESTTMP/reader-index-read")
> testing.wait_file(b"$TESTTMP/writer-revlog-unsplit")
> return r
>
> def extsetup(ui):
> extensions.wrapfunction(revlog.revlog, '_loadindex', _wait_post_load)
> EOF
setup a repository for tests
----------------------------
$ cat >> $HGRCPATH << EOF
> [format]
> revlog-compression=none
> EOF
$ hg init troffset-computation
$ cd troffset-computation
$ files="
> file
> Directory_With,Special%Char/Complex_File.babar
> foo/bar/babar_celeste/foo
> 1234567890/1234567890/1234567890/1234567890/1234567890/1234567890/1234567890/1234567890/1234567890/1234567890/f
> some_dir/sub_dir/foo_bar
> some_dir/sub_dir/foo_bar.i.s/tutu
> "
$ for f in $files; do
> mkdir -p `dirname $f`
> done
$ for f in $files; do
> printf '%20d' '1' > $f
> done
$ hg commit -Aqma
$ for f in $files; do
> printf '%1024d' '1' > $f
> done
$ hg commit -Aqmb
$ for f in $files; do
> printf '%20d' '1' > $f
> done
$ hg commit -Aqmc
$ for f in $files; do
> dd if=/dev/zero of=$f bs=1k count=128 > /dev/null 2>&1
> done
$ hg commit -AqmD --traceback
$ for f in $files; do
> dd if=/dev/zero of=$f bs=1k count=132 > /dev/null 2>&1
> done
$ hg commit -AqmD --traceback
Reference size:
$ f -s file
file: size=135168
$ f -s .hg/store/data*/file*
.hg/store/data/file.d: size=267307
.hg/store/data/file.i: size=320
$ cd ..
Test a succesful pull
=====================
Make sure everything goes though as expect if we don't do any crash
$ hg clone --quiet --rev 1 troffset-computation troffset-success
$ cd troffset-success
Reference size:
$ f -s file
file: size=1024
$ f -s .hg/store/data/file*
.hg/store/data/file.i: size=1174
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 18 changes to 6 files
new changesets c99a94cae9b1:64874a3b0160
(run 'hg update' to get a working copy)
The inline revlog has been replaced
$ f -s .hg/store/data/file*
.hg/store/data/file.d: size=267307
.hg/store/data/file.i: size=320
$ hg verify -q
$ cd ..
Test a hard crash after the file was split but before the transaction was committed
===================================================================================
Test offset computation to correctly factor in the index entries themselves.
Also test that the new data size has the correct size if the transaction is aborted
after the index has been replaced.
Test repo has commits a, b, c, D, where D is large (grows the revlog enough that it
transitions to non-inline storage). The clone initially has changes a, b
and will transition to non-inline storage when adding c, D.
If the transaction adding c, D is rolled back, then we don't undo the revlog split,
but truncate the index and the data to remove both c and D.
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-copy
$ cd troffset-computation-copy
Reference size:
$ f -s file
file: size=1024
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ cat > .hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup = python:$TESTTMP/killme.py:killme
> EOF
#if chg
$ hg pull ../troffset-computation
pulling from ../troffset-computation
[255]
#else
$ hg pull ../troffset-computation
pulling from ../troffset-computation
*Killed* (glob)
[137]
#endif
The inline revlog still exist, but a split version exist next to it
$ cat .hg/store/journal | tr '\0' ' ' | grep '\.s'
data/some_dir/sub_dir/foo_bar.i.s/tutu.i 1174
data/some_dir/sub_dir/foo_bar.i.s/tutu.d 0
$ f -s .hg/store/data*/file*
.hg/store/data-s/file: size=320
.hg/store/data/file.d: size=267307
.hg/store/data/file.i: size=132395
The first file.i entry should match the "Reference size" above.
The first file.d entry is the temporary record during the split,
A "temporary file" entry exist for the split index.
$ cat .hg/store/journal | tr -s '\000' ' ' | grep data/file
data/file.i 1174
data/file.d 0
$ cat .hg/store/journal.backupfiles | tr -s '\000' ' ' | tr -s '\00' ' '| grep 'data.*/file'
data/file.i data/journal.backup.file.i.bck 0
data-s/file 0
recover is rolling the split back, the fncache is still valid
$ hg recover
rolling back interrupted transaction
(verify step skipped, run `hg verify` to check your repository content)
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ hg tip
changeset: 1:64b04c8dc267
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg verify -q
$ hg debugrebuildfncache --only-data
fncache already up to date
$ hg verify -q
$ cd ..
Test a hard crash right before the index is move into place
===========================================================
Now retry the procedure but intercept the rename of the index and check that
the journal does not contain the new index size. This demonstrates the edge case
where the data file is left as garbage.
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-copy2
$ cd troffset-computation-copy2
Reference size:
$ f -s file
file: size=1024
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ cat > .hg/hgrc <<EOF
> [extensions]
> intercept_rename = $TESTTMP/intercept_before_rename.py
> EOF
#if chg
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
[255]
#else
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
*Killed* (glob)
[137]
#endif
The inline revlog still exist, but a split version exist next to it
$ f -s .hg/store/data*/file*
.hg/store/data-s/file: size=320
.hg/store/data/file.d: size=267307
.hg/store/data/file.i: size=132395
$ cat .hg/store/journal | tr -s '\000' ' ' | grep 'data.*/file'
data/file.i 1174
data/file.d 0
recover is rolling the split back, the fncache is still valid
$ hg recover
rolling back interrupted transaction
(verify step skipped, run `hg verify` to check your repository content)
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ hg tip
changeset: 1:64b04c8dc267
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg verify -q
$ cd ..
Test a hard crash right after the index is move into place
===========================================================
Now retry the procedure but intercept the rename of the index.
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-crash-after-rename
$ cd troffset-computation-crash-after-rename
Reference size:
$ f -s file
file: size=1024
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ cat > .hg/hgrc <<EOF
> [extensions]
> intercept_rename = $TESTTMP/intercept_after_rename.py
> EOF
#if chg
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
[255]
#else
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
*Killed* (glob)
[137]
#endif
The inline revlog was over written on disk
$ f -s .hg/store/data*/file*
.hg/store/data/file.d: size=267307
.hg/store/data/file.i: size=320
$ cat .hg/store/journal | tr -s '\000' ' ' | grep 'data.*/file'
data/file.i 1174
data/file.d 0
recover is rolling the split back, the fncache is still valid
$ hg recover
rolling back interrupted transaction
(verify step skipped, run `hg verify` to check your repository content)
$ f -s .hg/store/data*/file*
.hg/store/data/file.i: size=1174
$ hg tip
changeset: 1:64b04c8dc267
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg verify -q
$ cd ..
Have the transaction rollback itself without any hard crash
===========================================================
Repeat the original test but let hg rollback the transaction.
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-copy-rb
$ cd troffset-computation-copy-rb
$ cat > .hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup = false
> EOF
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
transaction abort!
rollback completed
abort: pretxnchangegroup hook exited with status 1
[40]
The split was rollback
$ f -s .hg/store/data*/file*
.hg/store/data/file.d: size=0
.hg/store/data/file.i: size=1174
$ hg tip
changeset: 1:64b04c8dc267
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg verify -q
$ cd ..
Read race
=========
We check that a client that started reading a revlog (its index) after the
split and end reading (the data) after the rollback should be fine
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-race
$ cd troffset-computation-race
$ cat > .hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup=$RUNTESTDIR/testlib/wait-on-file 5 $TESTTMP/reader-index-read $TESTTMP/writer-revlog-split
> pretxnclose = false
> EOF
start a reader
$ hg cat --rev 0 file \
> --config "extensions.wait_read=$TESTTMP/reader_wait_split.py" \
> 2> $TESTTMP/reader.stderr \
> > $TESTTMP/reader.stdout &
Do a failed pull in //
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
transaction abort!
rollback completed
abort: pretxnclose hook exited with status 1
[40]
$ touch $TESTTMP/writer-revlog-unsplit
$ wait
The reader should be fine
$ cat $TESTTMP/reader.stderr
$ cat $TESTTMP/reader.stdout
1 (no-eol)
$ hg verify -q
$ cd ..
pending hooks
=============
We checks that hooks properly see the inside of the transaction, while other process don't.
$ hg clone --quiet --rev 1 troffset-computation troffset-computation-hooks
$ cd troffset-computation-hooks
$ cat > .hg/hgrc <<EOF
> [hooks]
> pretxnclose.01-echo = hg cat -r 'max(all())' file | f --size
> pretxnclose.02-echo = $RUNTESTDIR/testlib/wait-on-file 5 $TESTTMP/hook-done $TESTTMP/hook-tr-ready
> pretxnclose.03-abort = false
> EOF
$ (
> $RUNTESTDIR/testlib/wait-on-file 5 $TESTTMP/hook-tr-ready;\
> hg cat -r 'max(all())' file | f --size;\
> touch $TESTTMP/hook-done
> ) >stdout 2>stderr &
$ hg pull ../troffset-computation
pulling from ../troffset-computation
searching for changes
adding changesets
adding manifests
adding file changes
size=135168
transaction abort!
rollback completed
abort: pretxnclose.03-abort hook exited with status 1
[40]
$ cat stdout
size=1024
$ cat stderr
$ hg verify -q
$ cd ..