lock: block signal interrupt while making a lock file
On Windows where symlink isn't supported, util.makelock() could leave an empty
file if interrupted immediately after os.open(). This empty lock never dies
as it has no process id recorded.
ld = os.open(pathname, os.O_CREAT | os.O_WRONLY | os.O_EXCL)
# an interrupt may occur here
os.write(ld, info)
os.close(ld)
This was a long-standing bug of TortoiseHg which runs a command-server and
kills it by CTRL_C_EVENT, reported by random Windows users.
https://bitbucket.org/tortoisehg/thg/issues/4873/#comment-
43591129
At first, I tried to fix makelock() to clean up a stale lock file, which
turned out to be hard because any instructions may be interrupted by a
signal.
ld = None
try:
# CALL_FUNCTION # os.open(...)
# an interrupt may occur here
# STORE_FAST # ld = ...
ld = os.open(pathname, os.O_CREAT | os.O_WRONLY | os.O_EXCL)
os.write(ld, info)
...
return True
except:
if ld:
...
os.unlink(pathname)
return False
So I decided to block signals by temporarily replacing the signal handlers
so makelcok() and held = 1 will never be interrupted.
Many thanks to Fernando Najera for investigating the issue.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> rebase=
>
> [alias]
> tlog = log --template "{rev}: {node|short} '{desc}' {branches}\n"
> tglog = tlog --graph
> EOF
$ hg init a
$ cd a
$ mkdir d
$ echo a > a
$ hg ci -Am A
adding a
$ echo b > d/b
$ hg ci -Am B
adding d/b
$ hg mv d d-renamed
moving d/b to d-renamed/b
$ hg ci -m 'rename B'
$ hg up -q -C 1
$ hg mv a a-renamed
$ echo x > d/x
$ hg add d/x
$ hg ci -m 'rename A'
created new head
$ hg tglog
@ 3: 73a3ee40125d 'rename A'
|
| o 2: 220d0626d185 'rename B'
|/
o 1: 3ab5da9a5c01 'B'
|
o 0: 1994f17a630e 'A'
Rename is tracked:
$ hg tlog -p --git -r tip
3: 73a3ee40125d 'rename A'
diff --git a/a b/a-renamed
rename from a
rename to a-renamed
diff --git a/d/x b/d/x
new file mode 100644
--- /dev/null
+++ b/d/x
@@ -0,0 +1,1 @@
+x
Rebase the revision containing the rename:
$ hg rebase -s 3 -d 2
rebasing 3:73a3ee40125d "rename A" (tip)
saved backup bundle to $TESTTMP/a/.hg/strip-backup/73a3ee40125d-1d78ebcf-rebase.hg
$ hg tglog
@ 3: 032a9b75e83b 'rename A'
|
o 2: 220d0626d185 'rename B'
|
o 1: 3ab5da9a5c01 'B'
|
o 0: 1994f17a630e 'A'
Rename is not lost:
$ hg tlog -p --git -r tip
3: 032a9b75e83b 'rename A'
diff --git a/a b/a-renamed
rename from a
rename to a-renamed
diff --git a/d-renamed/x b/d-renamed/x
new file mode 100644
--- /dev/null
+++ b/d-renamed/x
@@ -0,0 +1,1 @@
+x
Rebased revision does not contain information about b (issue3739)
$ hg log -r 3 --debug
changeset: 3:032a9b75e83bff1dcfb6cbfa4ef50a704bf1b569
tag: tip
phase: draft
parent: 2:220d0626d185f372d9d8f69d9c73b0811d7725f7
parent: -1:0000000000000000000000000000000000000000
manifest: 3:035d66b27a1b06b2d12b46d41a39adb7a200c370
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files+: a-renamed d-renamed/x
files-: a
extra: branch=default
extra: rebase_source=73a3ee40125d6f0f347082e5831ceccb3f005f8a
description:
rename A
$ cd ..
$ hg init b
$ cd b
$ echo a > a
$ hg ci -Am A
adding a
$ echo b > b
$ hg ci -Am B
adding b
$ hg cp b b-copied
$ hg ci -Am 'copy B'
$ hg up -q -C 1
$ hg cp a a-copied
$ hg ci -m 'copy A'
created new head
$ hg tglog
@ 3: 0a8162ff18a8 'copy A'
|
| o 2: 39e588434882 'copy B'
|/
o 1: 6c81ed0049f8 'B'
|
o 0: 1994f17a630e 'A'
Copy is tracked:
$ hg tlog -p --git -r tip
3: 0a8162ff18a8 'copy A'
diff --git a/a b/a-copied
copy from a
copy to a-copied
Rebase the revision containing the copy:
$ hg rebase -s 3 -d 2
rebasing 3:0a8162ff18a8 "copy A" (tip)
saved backup bundle to $TESTTMP/b/.hg/strip-backup/0a8162ff18a8-dd06302a-rebase.hg
$ hg tglog
@ 3: 98f6e6dbf45a 'copy A'
|
o 2: 39e588434882 'copy B'
|
o 1: 6c81ed0049f8 'B'
|
o 0: 1994f17a630e 'A'
Copy is not lost:
$ hg tlog -p --git -r tip
3: 98f6e6dbf45a 'copy A'
diff --git a/a b/a-copied
copy from a
copy to a-copied
Rebased revision does not contain information about b (issue3739)
$ hg log -r 3 --debug
changeset: 3:98f6e6dbf45ab54079c2237fbd11066a5c41a11d
tag: tip
phase: draft
parent: 2:39e588434882ff77d01229d169cdc77f29e8855e
parent: -1:0000000000000000000000000000000000000000
manifest: 3:2232f329d66fffe3930d43479ae624f66322b04d
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files+: a-copied
extra: branch=default
extra: rebase_source=0a8162ff18a8900df8df8ef7ac0046955205613e
description:
copy A
$ cd ..
Test rebase across repeating renames:
$ hg init repo
$ cd repo
$ echo testing > file1.txt
$ hg add file1.txt
$ hg ci -m "Adding file1"
$ hg rename file1.txt file2.txt
$ hg ci -m "Rename file1 to file2"
$ echo Unrelated change > unrelated.txt
$ hg add unrelated.txt
$ hg ci -m "Unrelated change"
$ hg rename file2.txt file1.txt
$ hg ci -m "Rename file2 back to file1"
$ hg update -r -2
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo Another unrelated change >> unrelated.txt
$ hg ci -m "Another unrelated change"
created new head
$ hg tglog
@ 4: b918d683b091 'Another unrelated change'
|
| o 3: 1ac17e43d8aa 'Rename file2 back to file1'
|/
o 2: 480101d66d8d 'Unrelated change'
|
o 1: be44c61debd2 'Rename file1 to file2'
|
o 0: 8ce9a346991d 'Adding file1'
$ hg rebase -s 4 -d 3
rebasing 4:b918d683b091 "Another unrelated change" (tip)
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/b918d683b091-3024bc57-rebase.hg
$ hg diff --stat -c .
unrelated.txt | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
$ cd ..
Verify that copies get preserved (issue4192).
$ hg init copy-gets-preserved
$ cd copy-gets-preserved
$ echo a > a
$ hg add a
$ hg commit --message "File a created"
$ hg copy a b
$ echo b > b
$ hg commit --message "File b created as copy of a and modified"
$ hg copy b c
$ echo c > c
$ hg commit --message "File c created as copy of b and modified"
$ hg copy c d
$ echo d > d
$ hg commit --message "File d created as copy of c and modified"
Note that there are four entries in the log for d
$ hg tglog --follow d
@ 3: 421b7e82bb85 'File d created as copy of c and modified'
|
o 2: 327f772bc074 'File c created as copy of b and modified'
|
o 1: 79d255d24ad2 'File b created as copy of a and modified'
|
o 0: b220cd6d2326 'File a created'
Update back to before we performed copies, and inject an unrelated change.
$ hg update 0
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
$ echo unrelated > unrelated
$ hg add unrelated
$ hg commit --message "Unrelated file created"
created new head
$ hg update 4
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
Rebase the copies on top of the unrelated change.
$ hg rebase --source 1 --dest 4
rebasing 1:79d255d24ad2 "File b created as copy of a and modified"
rebasing 2:327f772bc074 "File c created as copy of b and modified"
rebasing 3:421b7e82bb85 "File d created as copy of c and modified"
saved backup bundle to $TESTTMP/copy-gets-preserved/.hg/strip-backup/79d255d24ad2-a2265555-rebase.hg
$ hg update 4
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
There should still be four entries in the log for d
$ hg tglog --follow d
@ 4: dbb9ba033561 'File d created as copy of c and modified'
|
o 3: af74b229bc02 'File c created as copy of b and modified'
|
o 2: 68bf06433839 'File b created as copy of a and modified'
:
o 0: b220cd6d2326 'File a created'
Same steps as above, but with --collapse on rebase to make sure the
copy records collapse correctly.
$ hg co 1
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
$ echo more >> unrelated
$ hg ci -m 'unrelated commit is unrelated'
created new head
$ hg rebase -s 2 --dest 5 --collapse
rebasing 2:68bf06433839 "File b created as copy of a and modified"
rebasing 3:af74b229bc02 "File c created as copy of b and modified"
merging b and c to c
rebasing 4:dbb9ba033561 "File d created as copy of c and modified"
merging c and d to d
saved backup bundle to $TESTTMP/copy-gets-preserved/.hg/strip-backup/68bf06433839-dde37595-rebase.hg
$ hg co tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
This should show both revision 3 and 0 since 'd' was transitively a
copy of 'a'.
$ hg tglog --follow d
@ 3: 5a46b94210e5 'Collapsed revision
: * File b created as copy of a and modified
: * File c created as copy of b and modified
: * File d created as copy of c and modified'
o 0: b220cd6d2326 'File a created'
$ cd ..