branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
#require unix-permissions
test that new files created in .hg inherit the permissions from .hg/store
$ mkdir dir
just in case somebody has a strange $TMPDIR
$ chmod g-s dir
$ cd dir
$ cat >printmodes.py <<EOF
> import os
> import sys
>
> allnames = []
> isdir = {}
> for root, dirs, files in os.walk(sys.argv[1]):
> for d in dirs:
> name = os.path.join(root, d)
> isdir[name] = 1
> allnames.append(name)
> for f in files:
> name = os.path.join(root, f)
> allnames.append(name)
> allnames.sort()
> for name in allnames:
> suffix = name in isdir and '/' or ''
> print('%05o %s%s' % (os.lstat(name).st_mode & 0o7777, name, suffix))
> EOF
$ cat >mode.py <<EOF
> import os
> import sys
> print('%05o' % os.lstat(sys.argv[1]).st_mode)
> EOF
$ umask 077
$ hg init repo
$ cd repo
$ chmod 0770 .hg/store .hg/cache .hg/wcache
before commit
store can be written by the group, other files cannot
store is setgid
$ "$PYTHON" ../printmodes.py .
00700 ./.hg/
00600 ./.hg/00changelog.i
00770 ./.hg/cache/
00600 ./.hg/requires
00770 ./.hg/store/
00600 ./.hg/store/requires
00770 ./.hg/wcache/
$ mkdir dir
$ touch foo dir/bar
$ hg ci -qAm 'add files'
after commit
working dir files can only be written by the owner
files created in .hg can be written by the group
(in particular, store/**, dirstate, branch cache file, undo files)
new directories are setgid
$ "$PYTHON" ../printmodes.py .
00700 ./.hg/
00600 ./.hg/00changelog.i
00660 ./.hg/branch
00770 ./.hg/cache/
00660 ./.hg/cache/branch2-served
00660 ./.hg/cache/rbc-names-v1
00660 ./.hg/cache/rbc-revs-v1
00660 ./.hg/dirstate
00660 ./.hg/fsmonitor.state (fsmonitor !)
00660 ./.hg/last-message.txt
00600 ./.hg/requires
00770 ./.hg/store/
00660 ./.hg/store/00changelog-150e1cfc.nd (rust !)
00660 ./.hg/store/00changelog.d
00660 ./.hg/store/00changelog.i
00660 ./.hg/store/00changelog.n (rust !)
00660 ./.hg/store/00manifest.i
00770 ./.hg/store/data/
00770 ./.hg/store/data/dir/
00660 ./.hg/store/data/dir/bar.i (reporevlogstore !)
00660 ./.hg/store/data/foo.i (reporevlogstore !)
00770 ./.hg/store/data/dir/bar/ (reposimplestore !)
00660 ./.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ./.hg/store/data/dir/bar/index (reposimplestore !)
00770 ./.hg/store/data/foo/ (reposimplestore !)
00660 ./.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ./.hg/store/data/foo/index (reposimplestore !)
00660 ./.hg/store/fncache (repofncache !)
00660 ./.hg/store/phaseroots
00600 ./.hg/store/requires
00660 ./.hg/store/undo
00660 ./.hg/store/undo.backupfiles
00660 ./.hg/undo.backup.branch.bck
00660 ./.hg/undo.desc
00770 ./.hg/wcache/
00711 ./.hg/wcache/checkisexec
007.. ./.hg/wcache/checklink (re)
00600 ./.hg/wcache/checklink-target
00660 ./.hg/wcache/manifestfulltextcache (reporevlogstore !)
00700 ./dir/
00600 ./dir/bar
00600 ./foo
$ umask 007
$ hg init ../push
before push
group can write everything
$ "$PYTHON" ../printmodes.py ../push
00770 ../push/.hg/
00660 ../push/.hg/00changelog.i
00770 ../push/.hg/cache/
00660 ../push/.hg/requires
00770 ../push/.hg/store/
00660 ../push/.hg/store/requires
00770 ../push/.hg/wcache/
$ umask 077
$ hg -q push ../push
after push
group can still write everything
$ "$PYTHON" ../printmodes.py ../push
00770 ../push/.hg/
00660 ../push/.hg/00changelog.i
00660 ../push/.hg/branch
00770 ../push/.hg/cache/
00660 ../push/.hg/cache/branch2-base
00660 ../push/.hg/cache/rbc-names-v1
00660 ../push/.hg/cache/rbc-revs-v1
00660 ../push/.hg/requires
00770 ../push/.hg/store/
00660 ../push/.hg/store/00changelog-b870a51b.nd (rust !)
00660 ../push/.hg/store/00changelog.d
00660 ../push/.hg/store/00changelog.i
00660 ../push/.hg/store/00changelog.n (rust !)
00660 ../push/.hg/store/00manifest.i
00770 ../push/.hg/store/data/
00770 ../push/.hg/store/data/dir/
00660 ../push/.hg/store/data/dir/bar.i (reporevlogstore !)
00660 ../push/.hg/store/data/foo.i (reporevlogstore !)
00770 ../push/.hg/store/data/dir/bar/ (reposimplestore !)
00660 ../push/.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ../push/.hg/store/data/dir/bar/index (reposimplestore !)
00770 ../push/.hg/store/data/foo/ (reposimplestore !)
00660 ../push/.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ../push/.hg/store/data/foo/index (reposimplestore !)
00660 ../push/.hg/store/fncache (repofncache !)
00660 ../push/.hg/store/requires
00660 ../push/.hg/store/undo
00660 ../push/.hg/store/undo.backupfiles
00660 ../push/.hg/undo.backup.branch.bck
00660 ../push/.hg/undo.desc
00770 ../push/.hg/wcache/
Test that we don't lose the setgid bit when we call chmod.
Not all systems support setgid directories (e.g. HFS+), so
just check that directories have the same mode.
$ cd ..
$ hg init setgid
$ cd setgid
$ chmod g+rwx .hg/store
$ chmod g+s .hg/store 2> /dev/null || true
$ mkdir dir
$ touch dir/file
$ hg ci -qAm 'add dir/file'
$ storemode=`"$PYTHON" ../mode.py .hg/store`
$ dirmode=`"$PYTHON" ../mode.py .hg/store/data/dir`
$ if [ "$storemode" != "$dirmode" ]; then
> echo "$storemode != $dirmode"
> fi
$ cd ..
$ cd .. # g-s dir