+{-# LANGUAGE
+ EmptyDataDecls
+ , FlexibleInstances
+ , MultiParamTypeClasses
+ , UnicodeSyntax
+ #-}
module Sound.EsounD.Internals
( Frame(..)
, Channels(..)
, Mono
, Stereo
+ , interleave
+ , deinterleave
+ , toLSV
, wrapSocket
, closeSocket
, withCStrOrNull
+ , failOnError
)
where
-
import Bindings.EsounD
import Data.Int
+import Data.StorableVector as S
+import Data.StorableVector.Lazy as L
import Foreign.C.String
import Foreign.C.Types
import Foreign.Ptr
+import Foreign.Storable
+import Prelude.Unicode
import System.IO
import System.Posix.IO
import System.Posix.Types
-class Frame fr where
+class Storable fr ⇒ Frame fr where
frameFmt ∷ fr → C'esd_format_t
instance Frame Int8 where
class Channels ch where
channelFmt ∷ ch → C'esd_format_t
+-- Mono
data Mono
+
instance Channels Mono where
channelFmt _ = c'ESD_MONO
+-- Stereo
data Stereo
+
instance Channels Stereo where
channelFmt _ = c'ESD_STEREO
+{-# INLINE interleave #-}
+interleave ∷ Storable α ⇒ L.Vector α → L.Vector α → L.Vector α
+interleave l r
+ -- THINKME: consider using storablevector-streamfusion
+ = let Just (lFr, l') = L.viewL l
+ Just (rFr, r') = L.viewL r
+ lr' = interleave l' r'
+ in
+ L.cons lFr (L.cons rFr lr')
-wrapSocket :: String -> CInt → IO Handle
+{-# INLINE deinterleave #-}
+deinterleave ∷ Storable α ⇒ L.Vector α → (L.Vector α, L.Vector α)
+deinterleave v
+ -- THINKME: consider using storablevector-streamfusion
+ = let (lr, v') = L.splitAt 2 v
+ in
+ if L.null lr then
+ (L.empty, L.empty)
+ else
+ let Just (lFr, r) = L.viewL lr
+ Just (rFr, _) = L.viewL r
+ (l', r') = deinterleave v'
+ in
+ (L.cons lFr l', L.cons rFr r')
+
+-- Utility functions
+toLSV ∷ Storable α ⇒ S.Vector α → L.Vector α
+toLSV v = L.fromChunks [v]
+
+wrapSocket ∷ String → CInt → IO Handle
wrapSocket e (-1) = fail e
wrapSocket _ fd = fdToHandle (Fd fd)
-closeSocket :: Handle → IO ()
+closeSocket ∷ Handle → IO ()
closeSocket h = do (Fd fd) ← handleToFd h
_ ← c'esd_close (fromIntegral fd)
return ()
-withCStrOrNull :: Maybe String → (CString → IO a) → IO a
+withCStrOrNull ∷ Maybe String → (CString → IO a) → IO a
withCStrOrNull Nothing f = f nullPtr
withCStrOrNull (Just s) f = withCString s f
+
+failOnError ∷ Monad m ⇒ String → CInt → m ()
+failOnError msg rv
+ | rv ≤ 0 = fail msg
+ | otherwise = return ()