transaction: use the standard transaction mechanism to backup branch
Branch is a bit special :
- It currently does not collaborate with the transaction (or any scoping) for
writing (this is bad)
- It can change without the lock being taken (it is protected by `wlock`)
So we rely on the same mechanism as for the backup of the other dirstate file:
- we only do a backup if we hold the wlock
- we force a backup though the transaction
Since "branch" write does not collaborate with the transaction, we cannot back
it up "at the last minute" as we do for the dirstate. We have to back it up
"upfront". Since we have a backup, the transaction is no longer doing its
"quick_abort" and get noisy. Which is quite annoying. To work around this, and
to avoid jumping in yet-another-rabbit-hole of "getting branch written
properly", I am doing horrible things to the transaction in the meantime.
We should be able to get this code go away during the next cycle.
In the meantime, I prefer to take this small stop so that we stop abusing the
"journal" and "undo" mechanism instead of the proper backup mechanism of the
transaction.
Also note that this change regress the warning message for the legacy fallback
introduced in 2008 when issue902 got fixed in dd5a501cb97f (Mercurial 1.0).
I feel like this is fine as issue 902 remains fixed, and this would only affect
people deploying a mix of 15 year old Mercurial and modern mercurial, and using
branch and rollback extensively.
#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
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
$ 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
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
Push to repo r1 should break up most hardlinks in r2:
$ hg -R r2 verify -q
$ 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 -q
$ 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
[24] r4/.hg/branch (re)
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
[24] r4/.hg/undo.backup.branch (re)
2 r4/\.hg/undo\.backup\.dirstate (re)
2 r4/.hg/undo.desc
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/dirstate
2 r4/.hg/dirstate
2 r4/.hg/undo.backup.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
[23] r4/.hg/undo.backup.branch (re)
2 r4/\.hg/undo\.backup\.dirstate (re)
2 r4/.hg/undo.desc
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/dirstate
1 r4/.hg/dirstate
2 r4/.hg/undo.backup.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 ..