fncache: make debugrebuildfncache not fail on broken fncache
The code reading the fncache changed in 5.0, to complain if the file
is not \n terminated. This makes apparent the fact that the fncache
gets corrupted.
Make it possible to recover, instead of having `hg
debugrebuildfncache` failing by saying `(run hg debugrebuildfncache)`.
The corruption itself is most likely due to hg not using fsync in
general, and so various bad things can happen. Here, the reported
problems happened when running out of disk space. So I suspect that
because the fncache is much bigger than the average commit/pull, when
running out of disk space, the bulk of the pull may succeed, but the
new fncache may get half-written and still renamed into place.
Differential Revision: https://phab.mercurial-scm.org/D6722
#require execbit
$ umask 027
$ hg init test1
$ cd test1
$ touch a b
$ hg add a b
$ hg ci -m "added a b"
$ cd ..
$ hg clone test1 test3
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg init test2
$ cd test2
$ hg pull ../test1
pulling from ../test1
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 2 changes to 2 files
new changesets 22a449e20da5
(run 'hg update' to get a working copy)
$ hg co
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ chmod +x a
$ hg ci -m "chmod +x a"
the changelog should mention file a:
$ hg tip --template '{files}\n'
a
$ cd ../test1
$ echo 123 >>a
$ hg ci -m "a updated"
$ hg pull ../test2
pulling from ../test2
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files (+1 heads)
new changesets 7f4313b42a34
1 local changesets published
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg heads
changeset: 2:7f4313b42a34
tag: tip
parent: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: chmod +x a
changeset: 1:c6ecefc45368
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a updated
$ hg history
changeset: 2:7f4313b42a34
tag: tip
parent: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: chmod +x a
changeset: 1:c6ecefc45368
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a updated
changeset: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: added a b
$ hg -v merge
resolving manifests
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat a
123
$ [ -x a ]
$ cd ../test3
$ echo 123 >>b
$ hg ci -m "b updated"
$ hg pull ../test2
pulling from ../test2
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files (+1 heads)
new changesets 7f4313b42a34
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg heads
changeset: 2:7f4313b42a34
tag: tip
parent: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: chmod +x a
changeset: 1:dc57ead75f79
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b updated
$ hg history
changeset: 2:7f4313b42a34
tag: tip
parent: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: chmod +x a
changeset: 1:dc57ead75f79
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b updated
changeset: 0:22a449e20da5
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: added a b
$ hg -v merge
resolving manifests
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ ls -l ../test[123]/a > foo
$ cut -b 1-10 < foo
-rwxr-x---
-rwxr-x---
-rwxr-x---
$ hg debugindex a
rev linkrev nodeid p1 p2
0 0 b80de5d13875 000000000000 000000000000
$ hg debugindex -R ../test2 a
rev linkrev nodeid p1 p2
0 0 b80de5d13875 000000000000 000000000000
$ hg debugindex -R ../test1 a
rev linkrev nodeid p1 p2
0 0 b80de5d13875 000000000000 000000000000
1 1 7fe919cc0336 b80de5d13875 000000000000
$ cd ..