2012-06-04 23:43:29 +00:00
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{- locking between threads
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-
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2015-01-21 16:50:09 +00:00
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- Copyright 2012 Joey Hess <id@joeyh.name>
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2012-06-04 23:43:29 +00:00
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-
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2014-05-10 14:01:27 +00:00
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- License: BSD-2-clause
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2012-06-04 23:43:29 +00:00
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-}
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2019-11-23 15:07:22 +00:00
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module Utility.ThreadLock (
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Lock,
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newLock,
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withLock,
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) where
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2012-06-04 23:43:29 +00:00
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import Control.Concurrent.MVar
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type Lock = MVar ()
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newLock :: IO Lock
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newLock = newMVar ()
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{- Runs an action with a lock held, so only one thread at a time can run it. -}
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withLock :: Lock -> IO a -> IO a
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withLock lock = withMVar lock . const
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