root / src / Ganeti / Codec.hs @ 8c337f87
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{-| Provides interface to the 'zlib' library. |
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-} |
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{- |
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Copyright (C) 2014 Google Inc. |
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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This program is distributed in the hope that it will be useful, but |
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WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
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02110-1301, USA. |
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-} |
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module Ganeti.Codec |
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( compressZlib |
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, decompressZlib |
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) where |
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import Codec.Compression.Zlib (compress) |
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import qualified Codec.Compression.Zlib.Internal as I |
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import Control.Monad.Error |
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import qualified Data.ByteString.Lazy as BL |
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import qualified Data.ByteString.Lazy.Internal as BL |
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import Data.Monoid (mempty) |
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-- | Compresses a lazy bytestring. |
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compressZlib :: BL.ByteString -> BL.ByteString |
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compressZlib = compress |
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-- | Decompresses a lazy bytestring, throwing decoding errors using |
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-- 'throwError'. |
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decompressZlib :: (MonadError e m, Error e) => BL.ByteString -> m BL.ByteString |
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decompressZlib = I.foldDecompressStream |
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(liftM . BL.chunk) |
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(return mempty) |
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(const $ throwError . strMsg . ("Zlib: " ++)) |
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. I.decompressWithErrors |
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I.zlibFormat |
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I.defaultDecompressParams |