31 lines
761 B
Haskell
31 lines
761 B
Haskell
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{- git-annex assistant transfer slots
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-
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- Copyright 2012 Joey Hess <joey@kitenet.net>
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-
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- Licensed under the GNU GPL version 3 or higher.
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-}
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module Assistant.TransferSlots where
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import Control.Exception
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import Control.Concurrent
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type TransferSlots = QSemN
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{- Number of concurrent transfers allowed to be run from the assistant.
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-
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- Transfers launched by other means, including by remote assistants,
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- do not currently take up slots.
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-}
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numSlots :: Int
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numSlots = 1
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newTransferSlots :: IO TransferSlots
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newTransferSlots = newQSemN numSlots
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{- Waits until a transfer slot becomes available, and runs a transfer
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- action in the slot.
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-}
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inTransferSlot :: TransferSlots -> IO a -> IO a
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inTransferSlot s = bracket_ (waitQSemN s 1) (signalQSemN s 1)
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