Mercurial > hg
view tests/test-dirstate-race.t @ 36367:043e77f3be09
sshpeer: return framed file object when needed
Currently, wireproto.wirepeer has a default implementation of
_submitbatch() and sshv1peer has a very similar implementation.
The main difference is that sshv1peer is aware of the total amount
of bytes it can read whereas the default implementation reads the
stream until no more data is returned. The default implementation
works for HTTP, since there is a known end to HTTP responses (either
Content-Length or 0 sized chunk).
This commit teaches sshv1peer to use our just-introduced "cappedreader"
class for wrapping a file object to limit the number of bytes that
can be read. We do this by introducing an argument to specify whether
the response is framed. If set, we returned a cappedreader instance
instead of the raw pipe.
_call() always has framed responses. So we set this argument
unconditionally and then .read() the entirety of the result.
Strictly speaking, we don't need to use cappedreader in this case
and can inline frame decoding/read logic. But I like when things
are consistent. The overhead should be negligible.
_callstream() and _callcompressable() are special: whether framing
is used depends on the specific command. So, we define a set
of commands that have framed response. It currently only
contains "batch."
As a result of this change, the one-off implementation of
_submitbatch() in sshv1peer can be removed since it is now
safe to .read() the response's file object until end of stream.
cappedreader takes care of not overrunning the frame.
Differential Revision: https://phab.mercurial-scm.org/D2380
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 21 Feb 2018 08:35:48 -0800 |
parents | 4441705b7111 |
children | e787d97e90ad |
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$ hg init repo $ cd repo $ echo a > a $ hg add a $ hg commit -m test Do we ever miss a sub-second change?: $ for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do > hg co -qC 0 > echo b > a > hg st > done M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a M a $ echo test > b $ mkdir dir1 $ echo test > dir1/c $ echo test > d $ echo test > e #if execbit A directory will typically have the execute bit -- make sure it doesn't get confused with a file with the exec bit set $ chmod +x e #endif $ hg add b dir1 d e adding dir1/c $ hg commit -m test2 $ cat >> $TESTTMP/dirstaterace.py << EOF > from mercurial import ( > context, > extensions, > ) > def extsetup(): > extensions.wrapfunction(context.workingctx, '_checklookup', overridechecklookup) > def overridechecklookup(orig, self, files): > # make an update that changes the dirstate from underneath > self._repo.ui.system(r"sh '$TESTTMP/dirstaterace.sh'", > cwd=self._repo.root) > return orig(self, files) > EOF $ hg debugrebuilddirstate $ hg debugdirstate n 0 -1 unset a n 0 -1 unset b n 0 -1 unset d n 0 -1 unset dir1/c n 0 -1 unset e XXX Note that this returns M for files that got replaced by directories. This is definitely a bug, but the fix for that is hard and the next status run is fine anyway. $ cat > $TESTTMP/dirstaterace.sh <<EOF > rm b && rm -r dir1 && rm d && mkdir d && rm e && mkdir e > EOF $ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py M d M e ! b ! dir1/c $ hg debugdirstate n 644 2 * a (glob) n 0 -1 unset b n 0 -1 unset d n 0 -1 unset dir1/c n 0 -1 unset e $ hg status ! b ! d ! dir1/c ! e $ rmdir d e $ hg update -C -q . Test that dirstate changes aren't written out at the end of "hg status", if .hg/dirstate is already changed simultaneously before acquisition of wlock in workingctx._poststatusfixup(). This avoidance is important to keep consistency of dirstate in race condition (see issue5584 for detail). $ hg parents -q 1:* (glob) $ hg debugrebuilddirstate $ hg debugdirstate n 0 -1 unset a n 0 -1 unset b n 0 -1 unset d n 0 -1 unset dir1/c n 0 -1 unset e $ cat > $TESTTMP/dirstaterace.sh <<EOF > # This script assumes timetable of typical issue5584 case below: > # > # 1. "hg status" loads .hg/dirstate > # 2. "hg status" confirms clean-ness of FILE > # 3. "hg update -C 0" updates the working directory simultaneously > # (FILE is removed, and FILE is dropped from .hg/dirstate) > # 4. "hg status" acquires wlock > # (.hg/dirstate is re-loaded = no FILE entry in dirstate) > # 5. "hg status" marks FILE in dirstate as clean > # (FILE entry is added to in-memory dirstate) > # 6. "hg status" writes dirstate changes into .hg/dirstate > # (FILE entry is written into .hg/dirstate) > # > # To reproduce similar situation easily and certainly, #2 and #3 > # are swapped. "hg cat" below ensures #2 on "hg status" side. > > hg update -q -C 0 > hg cat -r 1 b > b > EOF "hg status" below should excludes "e", of which exec flag is set, for portability of test scenario, because unsure but missing "e" is treated differently in _checklookup() according to runtime platform. - "missing(!)" on POSIX, "pctx[f].cmp(self[f])" raises ENOENT - "modified(M)" on Windows, "self.flags(f) != pctx.flags(f)" is True $ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py --debug -X path:e skip updating dirstate: identity mismatch M a ! d ! dir1/c $ hg parents -q 0:* (glob) $ hg files a $ hg debugdirstate n * * * a (glob) $ rm b #if fsmonitor Create fsmonitor state. $ hg status $ f --type .hg/fsmonitor.state .hg/fsmonitor.state: file Test that invalidating fsmonitor state in the middle (which doesn't require the wlock) causes the fsmonitor update to be skipped. hg debugrebuilddirstate ensures that the dirstaterace hook will be called, but it also invalidates the fsmonitor state. So back it up and restore it. $ mv .hg/fsmonitor.state .hg/fsmonitor.state.tmp $ hg debugrebuilddirstate $ mv .hg/fsmonitor.state.tmp .hg/fsmonitor.state $ cat > $TESTTMP/dirstaterace.sh <<EOF > rm .hg/fsmonitor.state > EOF $ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py --debug skip updating fsmonitor.state: identity mismatch $ f .hg/fsmonitor.state .hg/fsmonitor.state: file not found #endif Set up a rebase situation for issue5581. $ echo c2 > a $ echo c2 > b $ hg add b $ hg commit -m c2 created new head $ echo c3 >> a $ hg commit -m c3 $ hg update 2 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo c4 >> a $ echo c4 >> b $ hg commit -m c4 created new head Configure a merge tool that runs status in the middle of the rebase. The goal of the status call is to trigger a potential bug if fsmonitor's state is written even though the wlock is held by another process. The output of 'hg status' in the merge tool goes to /dev/null because we're more interested in the results of 'hg status' run after the rebase. $ cat >> $TESTTMP/mergetool-race.sh << EOF > echo "custom merge tool" > printf "c2\nc3\nc4\n" > \$1 > hg --cwd "$TESTTMP/repo" status > /dev/null > echo "custom merge tool end" > EOF $ cat >> $HGRCPATH << EOF > [extensions] > rebase = > [merge-tools] > test.executable=sh > test.args=$TESTTMP/mergetool-race.sh \$output > EOF $ hg rebase -s . -d 3 --tool test rebasing 4:b08445fd6b2a "c4" (tip) merging a custom merge tool custom merge tool end saved backup bundle to $TESTTMP/repo/.hg/strip-backup/* (glob) This hg status should be empty, whether or not fsmonitor is enabled (issue5581). $ hg status