ui: restore behavior to ignore some I/O errors (issue5658)
e9646ff34d55 and 1bfb9a63b98e refactored ui methods to no longer
silently swallow some IOError instances. This is arguably the
correct thing to do. However, it had the unfortunate side-effect
of causing StdioError to bubble up to sensitive code like
transaction aborts, leading to an uncaught exceptions and failures
to e.g. roll back a transaction. This could occur when a remote
HTTP or SSH client connection dropped. The new behavior is
resulting in semi-frequent "abandonded transaction" errors on
multiple high-volume repositories at Mozilla.
This commit effectively reverts e9646ff34d55 and 1bfb9a63b98e to
restore the old behavior.
I agree with the principle that I/O errors shouldn't be ignored.
That makes this change... unfortunate. However, our hands are tied
for what to do on stable. I think the proper solution is for the
ui's behavior to be configurable (possibly via a context manager).
During critical sections like transaction rollback and abort, it
should be possible to suppress errors. But this feature would not
be appropriate on stable.
--- a/mercurial/ui.py Mon Aug 14 13:12:40 2017 -0700
+++ b/mercurial/ui.py Tue Aug 15 13:04:31 2017 -0700
@@ -904,7 +904,8 @@
if not getattr(self.ferr, 'closed', False):
self.ferr.flush()
except IOError as inst:
- raise error.StdioError(inst)
+ if inst.errno not in (errno.EPIPE, errno.EIO, errno.EBADF):
+ raise error.StdioError(inst)
def flush(self):
# opencode timeblockedsection because this is a critical path
@@ -913,12 +914,14 @@
try:
self.fout.flush()
except IOError as err:
- raise error.StdioError(err)
+ if err.errno not in (errno.EPIPE, errno.EIO, errno.EBADF):
+ raise error.StdioError(err)
finally:
try:
self.ferr.flush()
except IOError as err:
- raise error.StdioError(err)
+ if err.errno not in (errno.EPIPE, errno.EIO, errno.EBADF):
+ raise error.StdioError(err)
finally:
self._blockedtimes['stdio_blocked'] += \
(util.timer() - starttime) * 1000
--- a/tests/test-rollback.t Mon Aug 14 13:12:40 2017 -0700
+++ b/tests/test-rollback.t Tue Aug 15 13:04:31 2017 -0700
@@ -302,16 +302,12 @@
warn during txnclose
$ echo 1 > foo
$ hg --config ui.ioerrors=pretxncommit commit -m 'error during pretxncommit'
- error: pretxncommit.badui hook raised an exception: [Errno *] simulated epipe (glob)
- transaction abort!
- warn during abort
- rollback completed
- [255]
+ warn during pretxnclose
+ warn during txnclose
$ hg commit -m 'commit 1'
- warn during pretxncommit
- warn during pretxnclose
- warn during txnclose
+ nothing changed
+ [1]
$ cd ..
@@ -328,17 +324,11 @@
$ echo 1 > foo
$ hg --config ui.ioerrors=pretxnclose commit -m 'error during pretxnclose'
warn during pretxncommit
- error: pretxnclose.badui hook raised an exception: [Errno *] simulated eio (glob)
- transaction abort!
- warn during abort
- rollback completed
- abort: simulated eio
- [255]
+ warn during txnclose
$ hg commit -m 'commit 1'
- warn during pretxncommit
- warn during pretxnclose
- warn during txnclose
+ nothing changed
+ [1]
$ cd ..
@@ -356,8 +346,6 @@
$ hg --config ui.ioerrors=txnclose commit -m 'error during txnclose'
warn during pretxncommit
warn during pretxnclose
- error: txnclose.badui hook raised an exception: [Errno *] simulated badf (glob)
- (run with --traceback for stack trace)
$ hg commit -m 'commit 1'
nothing changed
@@ -378,15 +366,15 @@
$ echo 1 > foo
$ hg --config ui.ioerrors=msgabort --config hooks.pretxncommit=false commit -m 'error during abort message'
- abort: simulated ebadf
- *: DeprecationWarning: use lock.release instead of del lock (glob)
- return -1
+ warn during abort
+ rollback completed
+ abort: pretxncommit hook exited with status 1
[255]
$ hg commit -m 'commit 1'
- abort: abandoned transaction found!
- (run 'hg recover' to clean up transaction)
- [255]
+ warn during pretxncommit
+ warn during pretxnclose
+ warn during txnclose
$ cd ..
@@ -404,8 +392,6 @@
$ echo 1 > foo
$ hg --config ui.ioerrors=txnabort --config hooks.pretxncommit=false commit -m 'error during abort'
transaction abort!
- error: txnabort.badui hook raised an exception: [Errno *] simulated epipe (glob)
- (run with --traceback for stack trace)
rollback completed
abort: pretxncommit hook exited with status 1
[255]
@@ -433,7 +419,6 @@
$ hg --config ui.ioerrors=msgrollback --config hooks.pretxncommit=false commit -m 'error during rollback message'
transaction abort!
warn during abort
- rollback failed - please run hg recover
abort: pretxncommit hook exited with status 1
[255]
@@ -461,25 +446,12 @@
$ echo 1 > foo
$ hg --config ui.ioerrors=pretxncommit,pretxnclose,txnclose,txnabort,msgabort,msgrollback commit -m 'multiple errors'
- error: pretxncommit.badui hook raised an exception: [Errno *] simulated epipe (glob)
- abort: simulated ebadf
- *: DeprecationWarning: use lock.release instead of del lock (glob)
- return -1
- [255]
$ hg verify
- abandoned transaction found - run hg recover
checking changesets
checking manifests
- manifest@?: rev 1 points to nonexistent changeset 1
- manifest@?: 94e0ee43dbfe not in changesets
crosschecking files in changesets and manifests
checking files
- foo@?: rev 1 points to nonexistent changeset 1
- (expected 0)
- 1 files, 1 changesets, 2 total revisions
- 1 warnings encountered!
- 3 integrity errors encountered!
- [1]
+ 1 files, 2 changesets, 2 total revisions
$ cd ..