procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
#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
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.i
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/store/undo.phaseroots
00660 ./.hg/undo.backup.dirstate
00660 ./.hg/undo.bookmarks
00660 ./.hg/undo.branch
00660 ./.hg/undo.desc
00660 ./.hg/undo.dirstate
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
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/dirstate
00660 ../push/.hg/requires
00770 ../push/.hg/store/
00660 ../push/.hg/store/00changelog.i
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/store/undo.phaseroots
00660 ../push/.hg/undo.bookmarks
00660 ../push/.hg/undo.branch
00660 ../push/.hg/undo.desc
00660 ../push/.hg/undo.dirstate
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