test(journal): narrow down the problem with multiple write/reads

src/journal/src/Journal.hs

@@ -325,14 +325,29 @@ tj = do
 tbc :: IO ()
 tbc = do
   bb <- allocate 16
-  bc <- newBufferClaim bb 0 16
-  putBS bc 0 (BSChar8.pack "helloooooooooooo")
+  bc <- newBufferClaim bb 0 5
+  putBS bc 0 (BSChar8.pack "hello")
   bs <- getByteStringAt bb 0 5
-  putStrLn (BSChar8.unpack bs)
+  putStrLn ("'" ++ BSChar8.unpack bs ++ "'")
+  bc' <- newBufferClaim bb 5 6
+  putBS bc' 0 (BSChar8.pack "world!")
+  bs' <- getByteStringAt bb 5 6
+  putStrLn ("'" ++ BSChar8.unpack bs' ++ "'")
 
 tbb :: IO ()
 tbb = do
   bb <- allocate 16
   putByteStringAt bb 0 (BSChar8.pack "helloooooooooooo")
   bs <- getByteStringAt bb 0 5
   putStrLn (BSChar8.unpack bs)
+
+tfl :: IO ()
+tfl = do
+  bb <- allocate 16
+  writeFrameLength bb 0 5
+  HeaderLength headerLen <- readFrameLength bb 0
+  putStrLn ("headerLength: " ++ show headerLen)
+
+  writeFrameLength bb 4 {- (sizeOf (4 :: Word32)) -} 6
+  HeaderLength headerLen' <- readFrameLength bb 4 {- (sizeOf (4 :: Word32)) -}
+  putStrLn ("headerLength': " ++ show headerLen')

src/journal/src/Journal/Internal.hs

@@ -134,6 +134,8 @@ termAppenderClaim meta termBuffer termId termOffset len = do
     handleEndOfLogCondition termBuffer termOffset termLength termId
     return Nothing
   else do
+    putStrLn ("termAppenderClaim, termOffset: " ++
+              show (unTermOffset termOffset))
     putStrLn ("termAppenderClaim, frameLength: " ++
               show frameLength)
     headerWrite termBuffer termOffset (fromIntegral frameLength) termId
@@ -156,6 +158,8 @@ headerWrite termBuffer termOffset len _termId = do
   let versionFlagsType :: Int64
       versionFlagsType = fromIntegral cURRENT_VERSION `shiftL` 32
   -- XXX: Atomic write?
+  putStrLn ("headerWrite, versionFlagsType: " ++ show versionFlagsType)
+  putStrLn ("headerWrite, len: " ++ show (unHeaderLength len))
   writeInt64OffAddr termBuffer (fromIntegral termOffset + fRAME_LENGTH_FIELD_OFFSET)
     (versionFlagsType .|. ((- fromIntegral len) .&. 0xFFFF_FFFF))
   -- XXX: store termId and offset (only need for replication?)

src/journal/src/Journal/Internal/BufferClaim.hs

@@ -30,6 +30,8 @@ commit :: BufferClaim -> IO ()
 commit (BufferClaim bb) = do
   Position offset <- readPosition bb
   let Capacity frameLen = getCapacity bb
+  putStrLn ("commit, offset: " ++ show offset)
+  putStrLn ("commit, frameLen: " ++ show frameLen)
   writeFrameLength bb (fromIntegral offset) (fromIntegral frameLen)
 
 abort :: BufferClaim -> IO ()

src/journal/src/Journal/Internal/ByteBufferPtr.hs

@@ -320,9 +320,10 @@ getLazyByteString bb len = do
 getByteStringAt :: ByteBuffer -> Int -> Int -> IO BS.ByteString
 getByteStringAt bb offset len = do
   boundCheck bb (len - 1) -- XXX?
+  Slice slice <- readIORef (bbSlice bb)
   withForeignPtr (bbData bb) $ \sptr ->
     BS.create len $ \dptr ->
-      copyBytes dptr (sptr `plusPtr` offset) len
+      copyBytes dptr (sptr `plusPtr` (slice + offset)) len
 
 ------------------------------------------------------------------------
 -- * Relative operations on `Storable` elements
@@ -364,7 +365,7 @@ primitiveInt f c bb offset@(I# offset#) = do
   Slice (I# slice#) <- readIORef (bbSlice bb)
   withForeignPtr (bbData bb) $ \(Ptr addr#) ->
     IO $ \s ->
-      case f (addr# `plusAddr#` offset# `plusAddr#` slice#) 0# s of
+      case f (addr# `plusAddr#` (offset# +# slice#)) 0# s of
         (# s', i #) -> (# s', c i #)
 
 primitiveInt32 :: (Addr# -> Int# -> State# RealWorld -> (# State# RealWorld, Int# #))
@@ -383,7 +384,7 @@ primitiveInt_ f d bb offset@(I# offset#) i = do
   Slice (I# slice#) <- readIORef (bbSlice bb)
   withForeignPtr (bbData bb) $ \(Ptr addr#) ->
     IO $ \s ->
-      case f (addr# `plusAddr#` offset# `plusAddr#` slice#) 0# value# s of
+      case f (addr# `plusAddr#` (offset# +# slice#)) 0# value# s of
         s' -> (# s', () #)
 
 primitiveInt32_ :: (Addr# -> Int# -> Int# -> State# RealWorld -> State# RealWorld)

src/journal/src/Journal/Types.hs

@@ -323,7 +323,7 @@ tagString other   = "Unknown: " ++ show other
 newtype HeaderVersion = HeaderVersion Word8
   deriving newtype (Eq, Binary, Num, Storable, Integral, Real, Ord, Enum)
 
-newtype HeaderLength = HeaderLength Word32
+newtype HeaderLength = HeaderLength { unHeaderLength :: Word32 }
   deriving newtype (Eq, Ord, Binary, Enum, Real, Integral, Num, Storable)
 
 newtype HeaderIndex = HeaderIndex Word32