wireproto: correctly escape batched args and responses (issue4739)
This issue appears to be as old as wireproto batching itself: I can
reproduce the failure as far back as 08ef6b5f3715 trivially by
rebasing the test changes in this patch, which was back in the 1.9
era. I didn't test before that change, because prior to that the
testfile has a different name and I'm lazy.
Note that the test thought it was checking this case, but it actually
wasn't: it put a literal ; in the arg and response for its greet
command, but the mangle/unmangle step defined in the test meant that
instead of "Fo, =;o" going over the wire, "Gp-!><p" went instead,
which doesn't contain any special characters (those being [.=;]) and
thus not exercising the escaping. The test has been updated to use
pre-unmangled special characters, so the request is now "Fo+<:o",
which mangles to "Gp,=;p". I have confirmed that the test fails
without the adjustment to the escaping rules in wireproto.py.
No existing clients of RPC batching were depending on the old behavior
in any way. The only *actual* users of batchable RPCs in core were:
1) largefiles, wherein it batches up many statlfile calls. It sends
hexlified hashes over the wire and gets a 0, 1, or 2 back as a
response. No risk of special characters.
2) setdiscovery, which was using heads() and known(), both of which
communicate via hexlified nodes. Again, no risk of special characters.
Since the escaping functionality has been completely broken since it
was introduced, we know that it has no users. As such, we can change
the escaping mechanism without having to worry about backwards
compatibility issues.
For the curious, this was detected by chance: it happens that the
lz4-compressed text of a test file for remotefilelog compressed to
something containing a ;, which then caused the failure when I moved
remotefilelog to using batching for file content fetching.
prepare repo
$ hg init a
$ cd a
$ echo "some text" > FOO.txt
$ echo "another text" > bar.txt
$ echo "more text" > QUICK.txt
$ hg add
adding FOO.txt
adding QUICK.txt
adding bar.txt
$ hg ci -mtest1
verify
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
3 files, 1 changesets, 3 total revisions
verify with journal
$ touch .hg/store/journal
$ hg verify
abandoned transaction found - run hg recover
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
3 files, 1 changesets, 3 total revisions
$ rm .hg/store/journal
introduce some bugs in repo
$ cd .hg/store/data
$ mv _f_o_o.txt.i X_f_o_o.txt.i
$ mv bar.txt.i xbar.txt.i
$ rm _q_u_i_c_k.txt.i
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
warning: revlog 'data/FOO.txt.i' not in fncache!
0: empty or missing FOO.txt
FOO.txt@0: f62022d3d590 in manifests not found
warning: revlog 'data/QUICK.txt.i' not in fncache!
0: empty or missing QUICK.txt
QUICK.txt@0: 88b857db8eba in manifests not found
warning: revlog 'data/bar.txt.i' not in fncache!
0: empty or missing bar.txt
bar.txt@0: 256559129457 in manifests not found
3 files, 1 changesets, 0 total revisions
3 warnings encountered!
hint: run "hg debugrebuildfncache" to recover from corrupt fncache
6 integrity errors encountered!
(first damaged changeset appears to be 0)
[1]
$ cd ../../..
$ cd ..
test changelog without a manifest
$ hg init b
$ cd b
$ hg branch foo
marked working directory as branch foo
(branches are permanent and global, did you want a bookmark?)
$ hg ci -m branchfoo
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
0 files, 1 changesets, 0 total revisions
test revlog corruption
$ touch a
$ hg add a
$ hg ci -m a
$ echo 'corrupted' > b
$ dd if=.hg/store/data/a.i of=start bs=1 count=20 2>/dev/null
$ cat start b > .hg/store/data/a.i
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
a@1: broken revlog! (index data/a.i is corrupted)
warning: orphan revlog 'data/a.i'
1 files, 2 changesets, 0 total revisions
1 warnings encountered!
1 integrity errors encountered!
(first damaged changeset appears to be 1)
[1]
$ cd ..
test revlog format 0
$ revlog-formatv0.py
$ cd formatv0
$ hg verify
repository uses revlog format 0
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ cd ..