Mercurial > hg
view tests/test-issue1802.t @ 30446:b324b4e431e5
posix: give checkexec a fast path; keep the check files and test read only
Before, Mercurial would create a new temporary file every time, stat it, change
its exec mode, stat it again, and delete it. Most of this dance was done to
handle the rare and not-so-essential case of VFAT mounts on unix. The cost of
that was paid by the much more common and important case of using normal file
systems.
Instead, try to create and preserve .hg/cache/checkisexec and
.hg/cache/checknoexec with and without exec flag set. If the files exist and
have correct exec flags set, we can conclude that that file system supports the
exec flag. Best case, the whole exec check can thus be done with two stat
calls. Worst case, we delete the wrong files and check as usual. That will be
because temporary loss of exec bit or on file systems without support for the
exec bit. In that case we check as we did before, with the additional overhead
of one extra stat call.
It is possible that this different test algorithm in some cases on odd file
systems will give different behaviour. Again, I think it will be rare and
special cases and I think it is worth the risk.
test-clone.t happens to show the situation where checkisexec is left behind
from the old style check, while checknoexec only will be created next time a
exec check will be performed.
author | Mads Kiilerich <madski@unity3d.com> |
---|---|
date | Wed, 14 Jan 2015 01:15:26 +0100 |
parents | bd625cd4e5e7 |
children | eb586ed5d8ce |
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#require execbit Create extension that can disable exec checks: $ cat > noexec.py <<EOF > from mercurial import extensions, util > def setflags(orig, f, l, x): > pass > def checkexec(orig, path): > return False > def extsetup(ui): > extensions.wrapfunction(util, 'setflags', setflags) > extensions.wrapfunction(util, 'checkexec', checkexec) > EOF $ hg init unix-repo $ cd unix-repo $ touch a $ hg add a $ hg commit -m 'unix: add a' $ hg clone . ../win-repo updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ chmod +x a $ hg commit -m 'unix: chmod a' $ hg manifest -v 755 * a $ cd ../win-repo $ touch b $ hg add b $ hg commit -m 'win: add b' $ hg manifest -v 644 a 644 b $ hg pull pulling from $TESTTMP/unix-repo searching for changes adding changesets adding manifests adding file changes added 1 changesets with 0 changes to 0 files (+1 heads) (run 'hg heads' to see heads, 'hg merge' to merge) $ hg manifest -v -r tip 755 * a Simulate a Windows merge: $ hg --config extensions.n=$TESTTMP/noexec.py merge --debug searching for copies back to rev 1 unmatched files in local: b resolving manifests branchmerge: True, force: False, partial: False ancestor: a03b0deabf2b, local: d6fa54f68ae1+, remote: 2d8bcf2dda39 a: update permissions -> e 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) Simulate a Windows commit: $ hg --config extensions.n=$TESTTMP/noexec.py commit -m 'win: merge' $ hg manifest -v 755 * a 644 b $ cd ..