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 hardlink reporevlogstore
$ cat > nlinks.py <<EOF
> import sys
> from mercurial import pycompat, util
> for f in sorted(sys.stdin.readlines()):
> f = f[:-1]
> print(util.nlinks(pycompat.fsencode(f)), f)
> EOF
$ nlinksdir()
> {
> find "$@" -type f | "$PYTHON" $TESTTMP/nlinks.py
> }
Some implementations of cp can't create hardlinks (replaces 'cp -al' on Linux):
$ cat > linkcp.py <<EOF
> import sys
> from mercurial import pycompat, util
> util.copyfiles(pycompat.fsencode(sys.argv[1]),
> pycompat.fsencode(sys.argv[2]), hardlink=True)
> EOF
$ linkcp()
> {
> "$PYTHON" $TESTTMP/linkcp.py $1 $2
> }
Prepare repo r1:
$ hg init r1
$ cd r1
$ echo c1 > f1
$ hg add f1
$ hg ci -m0
$ mkdir d1
$ cd d1
$ echo c2 > f2
$ hg add f2
$ hg ci -m1
$ cd ../..
$ nlinksdir r1/.hg/store
1 r1/.hg/store/00changelog.i
1 r1/.hg/store/00manifest.i
1 r1/.hg/store/data/d1/f2.i
1 r1/.hg/store/data/f1.i
1 r1/.hg/store/fncache (repofncache !)
1 r1/.hg/store/phaseroots
1 r1/.hg/store/requires
1 r1/.hg/store/undo
1 r1/.hg/store/undo.backup.fncache (repofncache !)
1 r1/.hg/store/undo.backupfiles
1 r1/.hg/store/undo.phaseroots
Create hardlinked clone r2:
$ hg clone -U --debug r1 r2 --config progress.debug=true
linking: 1/7 files (14.29%)
linking: 2/7 files (28.57%)
linking: 3/7 files (42.86%)
linking: 4/7 files (57.14%)
linking: 5/7 files (71.43%)
linking: 6/7 files (85.71%)
linking: 7/7 files (100.00%)
linked 7 files
updating the branch cache
Create non-hardlinked clone r3:
$ hg clone --pull r1 r3
requesting all changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
new changesets 40d85e9847f2:7069c422939c
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
Repos r1 and r2 should now contain hardlinked files:
$ nlinksdir r1/.hg/store
2 r1/.hg/store/00changelog.i
2 r1/.hg/store/00manifest.i
2 r1/.hg/store/data/d1/f2.i
2 r1/.hg/store/data/f1.i
1 r1/.hg/store/fncache (repofncache !)
1 r1/.hg/store/phaseroots
1 r1/.hg/store/requires
1 r1/.hg/store/undo
1 r1/.hg/store/undo.backup.fncache (repofncache !)
1 r1/.hg/store/undo.backupfiles
1 r1/.hg/store/undo.phaseroots
$ nlinksdir r2/.hg/store
2 r2/.hg/store/00changelog.i
2 r2/.hg/store/00manifest.i
2 r2/.hg/store/data/d1/f2.i
2 r2/.hg/store/data/f1.i
1 r2/.hg/store/fncache (repofncache !)
1 r2/.hg/store/requires
Repo r3 should not be hardlinked:
$ nlinksdir r3/.hg/store
1 r3/.hg/store/00changelog.i
1 r3/.hg/store/00manifest.i
1 r3/.hg/store/data/d1/f2.i
1 r3/.hg/store/data/f1.i
1 r3/.hg/store/fncache (repofncache !)
1 r3/.hg/store/phaseroots
1 r3/.hg/store/requires
1 r3/.hg/store/undo
1 r3/.hg/store/undo.backupfiles
1 r3/.hg/store/undo.phaseroots
Create a non-inlined filelog in r3:
$ cd r3/d1
>>> f = open('data1', 'wb')
>>> for x in range(10000):
... f.write(b"%d\n" % x) and None
>>> f.close()
$ for j in 0 1 2 3 4 5 6 7 8 9; do
> cat data1 >> f2
> hg commit -m$j
> done
$ cd ../..
$ nlinksdir r3/.hg/store
1 r3/.hg/store/00changelog.i
1 r3/.hg/store/00manifest.i
1 r3/.hg/store/data/d1/f2.d
1 r3/.hg/store/data/d1/f2.i
1 r3/.hg/store/data/f1.i
1 r3/.hg/store/fncache (repofncache !)
1 r3/.hg/store/phaseroots
1 r3/.hg/store/requires
1 r3/.hg/store/undo
1 r3/.hg/store/undo.backup.fncache (repofncache !)
1 r3/.hg/store/undo.backup.phaseroots
1 r3/.hg/store/undo.backupfiles
1 r3/.hg/store/undo.phaseroots
Push to repo r1 should break up most hardlinks in r2:
$ hg -R r2 verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 2 changes to 2 files
$ cd r3
$ hg push
pushing to $TESTTMP/r1
searching for changes
adding changesets
adding manifests
adding file changes
added 10 changesets with 10 changes to 1 files
$ cd ..
$ nlinksdir r2/.hg/store
1 r2/.hg/store/00changelog.i
1 r2/.hg/store/00manifest.i
1 r2/.hg/store/data/d1/f2.i
2 r2/.hg/store/data/f1.i
[12] r2/\.hg/store/fncache (re) (repofncache !)
1 r2/.hg/store/requires
#if hardlink-whitelisted repofncache
$ nlinksdir r2/.hg/store/fncache
1 r2/.hg/store/fncache
#endif
$ hg -R r2 verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 2 changes to 2 files
$ cd r1
$ hg up
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
Committing a change to f1 in r1 must break up hardlink f1.i in r2:
$ echo c1c1 >> f1
$ hg ci -m00
$ cd ..
$ nlinksdir r2/.hg/store
1 r2/.hg/store/00changelog.i
1 r2/.hg/store/00manifest.i
1 r2/.hg/store/data/d1/f2.i
1 r2/.hg/store/data/f1.i
1 r2/.hg/store/fncache (repofncache !)
1 r2/.hg/store/requires
#if hardlink-whitelisted repofncache
$ nlinksdir r2/.hg/store/fncache
1 r2/.hg/store/fncache
#endif
Create a file which exec permissions we will change
$ cd r3
$ echo "echo hello world" > f3
$ hg add f3
$ hg ci -mf3
$ cd ..
$ cd r3
$ hg tip --template '{rev}:{node|short}\n'
12:d3b77733a28a
$ echo bla > f1
$ chmod +x f3
$ hg ci -m1
$ cd ..
Create hardlinked copy r4 of r3 (on Linux, we would call 'cp -al'):
$ linkcp r3 r4
'checklink' is produced by hardlinking a symlink, which is undefined whether
the symlink should be followed or not. It does behave differently on Linux and
BSD. Just remove it so the test pass on both platforms.
$ rm -f r4/.hg/wcache/checklink
r4 has hardlinks in the working dir (not just inside .hg):
$ nlinksdir r4
2 r4/.hg/00changelog.i
2 r4/.hg/branch
2 r4/.hg/cache/branch2-base
2 r4/.hg/cache/branch2-immutable
2 r4/.hg/cache/branch2-served
2 r4/.hg/cache/branch2-served.hidden
2 r4/.hg/cache/branch2-visible
2 r4/.hg/cache/branch2-visible-hidden
2 r4/.hg/cache/rbc-names-v1
2 r4/.hg/cache/rbc-revs-v1
2 r4/.hg/cache/tags2
2 r4/.hg/cache/tags2-served
2 r4/.hg/dirstate
2 r4/.hg/fsmonitor.state (fsmonitor !)
2 r4/.hg/hgrc
2 r4/.hg/last-message.txt
2 r4/.hg/requires
2 r4/.hg/store/00changelog.i
2 r4/.hg/store/00manifest.i
2 r4/.hg/store/data/d1/f2.d
2 r4/.hg/store/data/d1/f2.i
2 r4/.hg/store/data/f1.i
2 r4/.hg/store/data/f3.i
2 r4/.hg/store/fncache (repofncache !)
2 r4/.hg/store/phaseroots
2 r4/.hg/store/requires
2 r4/.hg/store/undo
2 r4/.hg/store/undo.backup.fncache (repofncache !)
2 r4/.hg/store/undo.backup.phaseroots
2 r4/.hg/store/undo.backupfiles
2 r4/.hg/store/undo.phaseroots
[24] r4/\.hg/undo\.backup\.dirstate (re)
2 r4/.hg/undo.bookmarks
2 r4/.hg/undo.branch
2 r4/.hg/undo.desc
[24] r4/\.hg/undo\.dirstate (re)
2 r4/.hg/wcache/checkisexec (execbit !)
2 r4/.hg/wcache/checklink-target (symlink !)
2 r4/.hg/wcache/checknoexec (execbit !)
2 r4/.hg/wcache/manifestfulltextcache (reporevlogstore !)
2 r4/d1/data1
2 r4/d1/f2
2 r4/f1
2 r4/f3
Update back to revision 12 in r4 should break hardlink of file f1 and f3:
#if hardlink-whitelisted
$ nlinksdir r4/.hg/undo.backup.dirstate r4/.hg/undo.dirstate
4 r4/.hg/undo.backup.dirstate
4 r4/.hg/undo.dirstate
#endif
$ hg -R r4 up 12
2 files updated, 0 files merged, 0 files removed, 0 files unresolved (execbit !)
1 files updated, 0 files merged, 0 files removed, 0 files unresolved (no-execbit !)
$ nlinksdir r4
2 r4/.hg/00changelog.i
1 r4/.hg/branch
2 r4/.hg/cache/branch2-base
2 r4/.hg/cache/branch2-immutable
2 r4/.hg/cache/branch2-served
2 r4/.hg/cache/branch2-served.hidden
2 r4/.hg/cache/branch2-visible
2 r4/.hg/cache/branch2-visible-hidden
2 r4/.hg/cache/rbc-names-v1
2 r4/.hg/cache/rbc-revs-v1
2 r4/.hg/cache/tags2
2 r4/.hg/cache/tags2-served
1 r4/.hg/dirstate
1 r4/.hg/fsmonitor.state (fsmonitor !)
2 r4/.hg/hgrc
2 r4/.hg/last-message.txt
2 r4/.hg/requires
2 r4/.hg/store/00changelog.i
2 r4/.hg/store/00manifest.i
2 r4/.hg/store/data/d1/f2.d
2 r4/.hg/store/data/d1/f2.i
2 r4/.hg/store/data/f1.i
2 r4/.hg/store/data/f3.i
2 r4/.hg/store/fncache
2 r4/.hg/store/phaseroots
2 r4/.hg/store/requires
2 r4/.hg/store/undo
2 r4/.hg/store/undo.backup.fncache (repofncache !)
2 r4/.hg/store/undo.backup.phaseroots
2 r4/.hg/store/undo.backupfiles
2 r4/.hg/store/undo.phaseroots
[24] r4/\.hg/undo\.backup\.dirstate (re)
2 r4/.hg/undo.bookmarks
2 r4/.hg/undo.branch
2 r4/.hg/undo.desc
[24] r4/\.hg/undo\.dirstate (re)
2 r4/.hg/wcache/checkisexec (execbit !)
2 r4/.hg/wcache/checklink-target (symlink !)
2 r4/.hg/wcache/checknoexec (execbit !)
1 r4/.hg/wcache/manifestfulltextcache (reporevlogstore !)
2 r4/d1/data1
2 r4/d1/f2
1 r4/f1
1 r4/f3 (execbit !)
2 r4/f3 (no-execbit !)
#if hardlink-whitelisted
$ nlinksdir r4/.hg/undo.backup.dirstate r4/.hg/undo.dirstate
4 r4/.hg/undo.backup.dirstate
4 r4/.hg/undo.dirstate
#endif
Test hardlinking outside hg:
$ mkdir x
$ echo foo > x/a
$ linkcp x y
$ echo bar >> y/a
No diff if hardlink:
$ diff x/a y/a
Test mq hardlinking:
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init a
$ cd a
$ hg qimport -n foo - << EOF
> # HG changeset patch
> # Date 1 0
> diff -r 2588a8b53d66 a
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/a Wed Jul 23 15:54:29 2008 +0200
> @@ -0,0 +1,1 @@
> +a
> EOF
adding foo to series file
$ hg qpush
applying foo
now at: foo
$ cd ..
$ linkcp a b
$ cd b
$ hg qimport -n bar - << EOF
> # HG changeset patch
> # Date 2 0
> diff -r 2588a8b53d66 a
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/b Wed Jul 23 15:54:29 2008 +0200
> @@ -0,0 +1,1 @@
> +b
> EOF
adding bar to series file
$ hg qpush
applying bar
now at: bar
$ cat .hg/patches/status
430ed4828a74fa4047bc816a25500f7472ab4bfe:foo
4e7abb4840c46a910f6d7b4d3c3fc7e5209e684c:bar
$ cat .hg/patches/series
foo
bar
$ cat ../a/.hg/patches/status
430ed4828a74fa4047bc816a25500f7472ab4bfe:foo
$ cat ../a/.hg/patches/series
foo
Test tags hardlinking:
$ hg qdel -r qbase:qtip
patch foo finalized without changeset message
patch bar finalized without changeset message
$ hg tag -l lfoo
$ hg tag foo
$ cd ..
$ linkcp b c
$ cd c
$ hg tag -l -r 0 lbar
$ hg tag -r 0 bar
$ cat .hgtags
4e7abb4840c46a910f6d7b4d3c3fc7e5209e684c foo
430ed4828a74fa4047bc816a25500f7472ab4bfe bar
$ cat .hg/localtags
4e7abb4840c46a910f6d7b4d3c3fc7e5209e684c lfoo
430ed4828a74fa4047bc816a25500f7472ab4bfe lbar
$ cat ../b/.hgtags
4e7abb4840c46a910f6d7b4d3c3fc7e5209e684c foo
$ cat ../b/.hg/localtags
4e7abb4840c46a910f6d7b4d3c3fc7e5209e684c lfoo
$ cd ..