1 files changed, 50 insertions, 0 deletions
diff --git a/src/Haddock/InterfaceFile.hs b/src/Haddock/InterfaceFile.hs
new file mode 100644
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--- /dev/null
+++ b/src/Haddock/InterfaceFile.hs
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+module Haddock.InterfaceFile (
+  InterfaceFile(..),
+  writeInterfaceFile,
+  readInterfaceFile
+) where
+
+import HaddockTypes
+import Haddock.Exception
+
+import Binary
+import System.IO
+import Data.Word
+import qualified Data.Map as Map
+import Control.Monad
+
+data InterfaceFile = InterfaceFile {
+  ifDocEnv :: DocEnv
+} 
+
+instance Binary InterfaceFile where
+  put_ bh (InterfaceFile docEnv) = put_ bh (Map.toList docEnv)
+  get bh = do
+    envList <- get bh
+    return (InterfaceFile (Map.fromList envList))
+
+packageFileMagic = 0xDA303001 :: Word32
+packageFileVersion = 0 :: Word16
+
+writeInterfaceFile :: FilePath -> InterfaceFile -> IO ()
+writeInterfaceFile filename iface = do 
+  h <- openBinaryFile filename WriteMode
+  bh <- openBinIO h
+  ud <- newWriteState
+  bh <- return $ setUserData bh ud
+  put_ bh packageFileMagic
+  put_ bh packageFileVersion
+  put_ bh iface
+  hClose h
+    
+readInterfaceFile :: FilePath -> IO InterfaceFile
+readInterfaceFile filename = do
+  h <- openBinaryFile filename ReadMode
+  bh <- openBinIO h
+  ud <- newReadState undefined
+  bh <- return (setUserData bh ud)
+  magic <- get bh
+  when (magic /= packageFileMagic) $ throwE $
+    "Magic number mismatch: couldn't load interface file: " ++ filename
+  (version :: Word16) <- get bh
+  get bh