takano-akio / filelock Goto Github PK

I adapted tests.hs and provided directions to reproduce the problem in jmitchell@4a850dd.

Is there a different way I should secure a lock, write to the locked file, and then release the lock?

I suspect what's happening is some low-level write/close operation is attempting to lock as well and causing a FILE LOCK CONFLICT. However, writing to a file without using System.FileLock results in no LockFile operations according to Process Monitor. This suggests low-level file writing/closing operations behavior varies depending on the existence of a lock, and inexplicably re-lock when there's already a lock.

It's possible System.FileLock's upstream APIs broke this use case, or perhaps there's an issue with the LockFileEx wrapper.

I get this error locally with GHC 9.6.0, but it is also reproduced by the CI:

$ cabal test interrupt --test-show-details=direct
Build profile: -w ghc-9.6.0.20230128 -O1
In order, the following will be built (use -v for more details):
 - filelock-0.1.1.5 (test:interrupt) (configuration changed)
...
Running 1 test suites...
Test suite interrupt: RUNNING...
interrupt: interrupt_test.lock: openFdAt: does not exist (No such file or directory)
Test suite interrupt: FAIL

This might be due to changes in the unix package from 2.7 to 2.8, but I don't know...

If lockFile is waiting for the lock then it can't be interrupted with an async exception (killThread, System.Timeout.timeout, etc...).

Citing from https://hydra.nixos.org/build/59842744/nixlog/1:

running tests
Running 1 test suites...
Test suite test: RUNNING...
log mismatch!
Test suite test: FAIL

To continue maintenance, I moved the package to https://github.com/haskell-pkg-janitors/filelock.
From now, please file issues and pull requests there.