Abstract some posix/windows stuff for portability

Author: harendra-kumar

core/src/Streamly/Internal/FileSystem/Path.hs

@@ -119,18 +119,41 @@
 --
 
 #if defined(mingw32_HOST_OS) || defined(__MINGW32__)
+-- #define IS_WINDOWS
 #define OS_PATH WindowsPath
+#define FS_WORD Word16
+#define FS_CSTRING CWString
 #else
 #define OS_PATH PosixPath
+#define FS_WORD Word8
+#define FS_CSTRING CString
 #endif
 
+-- #define IS_PORTABLE
+-- #include "Streamly/Internal/FileSystem/PosixPath.hs"
+
 module Streamly.Internal.FileSystem.Path
     (
       Path
+    , FsWord
+    , FsCString
+    , asFsCString
     , module Streamly.Internal.FileSystem.OS_PATH
     )
 where
 
+import Data.Word (FS_WORD)
+import Foreign.C.String (FS_CSTRING)
 import Streamly.Internal.FileSystem.OS_PATH
 
 type Path = OS_PATH
+type FsWord = FS_WORD
+type FsCString = FS_CSTRING
+
+{-# INLINE asFsCString #-}
+asFsCString :: OS_PATH -> (FsCString -> IO a) -> IO a
+#if defined(mingw32_HOST_OS) || defined(__MINGW32__)
+asFsCString = asCWString
+#else
+asFsCString = asCString
+#endif