diff options
| author |  Joey Hess <joeyh@joeyh.name> | 2015-05-18 14:16:49 -0400 |
|---|---|---|
| committer | Joey Hess <joeyh@joeyh.name> | 2015-05-18 15:57:17 -0400 |
| commit | 94a3e606fb31150c969d63790ec1ef870f413cc1 (patch) | |
| tree | 566860a856e7d064e18de4c3a8a2e561377caf3c /Utility/LockFile | |
| parent | 6a318cf0c050f9fa7959874bf0eb8f1105ef0a4b (diff) | |
lock pools to work around non-concurrency/composition safety of POSIX fcntl
Diffstat (limited to 'Utility/LockFile')
| -rw-r--r-- | Utility/LockFile/Posix.hs | 14 | ||||
| -rw-r--r-- | Utility/LockFile/Windows.hs | 2 |
2 files changed, 5 insertions, 11 deletions
diff --git a/Utility/LockFile/Posix.hs b/Utility/LockFile/Posix.hs index 9013bd32c..12275c48a 100644 --- a/Utility/LockFile/Posix.hs +++ b/Utility/LockFile/Posix.hs @@ -12,7 +12,6 @@ module Utility.LockFile.Posix ( tryLockExclusive, createLockFile, openExistingLockFile, - isLocked, checkLocked, getLockStatus, dropLock, @@ -73,28 +72,23 @@ openLockFile filemode lockfile = do setFdOption l CloseOnExec True return l --- Check if a file is locked, either exclusively, or with shared lock. --- When the file doesn't exist, it's considered not locked. -isLocked :: LockFile -> IO Bool -isLocked = fromMaybe False <$$> checkLocked - -- Returns Nothing when the file doesn't exist, for cases where -- that is different from it not being locked. checkLocked :: LockFile -> IO (Maybe Bool) checkLocked = maybe Nothing (Just . isJust) <$$> getLockStatus' -getLockStatus :: LockFile -> IO (Maybe (ProcessID, FileLock)) +getLockStatus :: LockFile -> IO (Maybe ProcessID) getLockStatus = fromMaybe Nothing <$$> getLockStatus' -getLockStatus' :: LockFile -> IO (Maybe (Maybe (ProcessID, FileLock))) +getLockStatus' :: LockFile -> IO (Maybe (Maybe ProcessID)) getLockStatus' lockfile = go =<< catchMaybeIO open where open = openFd lockfile ReadOnly Nothing defaultFileFlags go Nothing = return Nothing go (Just h) = do - ret <- getLock h (ReadLock, AbsoluteSeek, 0, 0) + v <- getLock h (ReadLock, AbsoluteSeek, 0, 0) closeFd h - return (Just ret) + return (Just (fmap fst v)) dropLock :: LockHandle -> IO () dropLock (LockHandle fd) = closeFd fd diff --git a/Utility/LockFile/Windows.hs b/Utility/LockFile/Windows.hs index 3c680d91c..fe57ff9eb 100644 --- a/Utility/LockFile/Windows.hs +++ b/Utility/LockFile/Windows.hs @@ -22,7 +22,7 @@ type LockFile = FilePath type LockHandle = HANDLE {- Tries to lock a file with a shared lock, which allows other processes to - - also lock it shared. Fails is the file is exclusively locked. -} + - also lock it shared. Fails if the file is exclusively locked. -} lockShared :: LockFile -> IO (Maybe LockHandle) lockShared = openLock fILE_SHARE_READ |