1 files changed, 69 insertions, 0 deletions
diff --git a/src/jaegertracing/thrift/lib/hs/src/Thrift/Transport/IOBuffer.hs b/src/jaegertracing/thrift/lib/hs/src/Thrift/Transport/IOBuffer.hs
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+++ b/src/jaegertracing/thrift/lib/hs/src/Thrift/Transport/IOBuffer.hs
@@ -0,0 +1,69 @@
+--
+-- Licensed to the Apache Software Foundation (ASF) under one
+-- or more contributor license agreements. See the NOTICE file
+-- distributed with this work for additional information
+-- regarding copyright ownership. The ASF licenses this file
+-- to you under the Apache License, Version 2.0 (the
+-- "License"); you may not use this file except in compliance
+-- with the License. You may obtain a copy of the License at
+--
+--   http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing,
+-- software distributed under the License is distributed on an
+-- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+-- KIND, either express or implied. See the License for the
+-- specific language governing permissions and limitations
+-- under the License.
+--
+
+module Thrift.Transport.IOBuffer
+       ( WriteBuffer
+       , newWriteBuffer
+       , writeBuf
+       , flushBuf
+       , ReadBuffer
+       , newReadBuffer
+       , fillBuf
+       , readBuf
+       , peekBuf
+       ) where
+
+import Data.ByteString.Lazy.Builder
+import Data.Functor
+import Data.IORef
+import Data.Monoid
+import Data.Word
+
+import qualified Data.ByteString.Lazy as LBS
+
+type WriteBuffer = IORef Builder
+type ReadBuffer = IORef LBS.ByteString
+
+newWriteBuffer :: IO WriteBuffer
+newWriteBuffer = newIORef mempty
+
+writeBuf :: WriteBuffer -> LBS.ByteString -> IO ()
+writeBuf w s = modifyIORef w ( <> lazyByteString s)
+
+flushBuf :: WriteBuffer -> IO LBS.ByteString
+flushBuf w = do
+  buf <- readIORef w
+  writeIORef w mempty
+  return $ toLazyByteString buf
+
+newReadBuffer :: IO ReadBuffer
+newReadBuffer = newIORef mempty
+
+fillBuf :: ReadBuffer -> LBS.ByteString -> IO ()
+fillBuf = writeIORef
+
+readBuf :: ReadBuffer -> Int -> IO LBS.ByteString
+readBuf r n = do
+  bs <- readIORef r
+  let (hd, tl) = LBS.splitAt (fromIntegral n) bs
+  writeIORef r tl
+  return hd
+
+peekBuf :: ReadBuffer -> IO (Maybe Word8)
+peekBuf r = (fmap fst . LBS.uncons) <$> readIORef r