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[EsounD.git] / Sound / EsounD / Internals.hs

diff --git a/Sound/EsounD/Internals.hs b/Sound/EsounD/Internals.hs
index f4b067f0903cf30fc9a23b62ccb13dee41c5e4fe..997899a6291e0ae05a100110a5300564e45d0b58 100644 (file)
--- a/Sound/EsounD/Internals.hs
+++ b/Sound/EsounD/Internals.hs
@@ -28,34 +28,39 @@ 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 Storable fr ⇒ Frame fr where
-    frameFmt ∷ fr → C'esd_format_t
+    frameFmt  ∷ fr → C'esd_format_t
+    frameSize ∷ fr → Int
 
 instance Frame Int8 where
-    frameFmt _ = c'ESD_BITS8
+    frameFmt  _ = c'ESD_BITS8
+    frameSize _ = 1
 
 instance Frame Int16 where
-    frameFmt _ = c'ESD_BITS16
+    frameFmt  _ = c'ESD_BITS16
+    frameSize _ = 2
 
 class Channels ch where
-    channelFmt ∷ ch → C'esd_format_t
+    channelFmt  ∷ ch → C'esd_format_t
+    numChannels ∷ ch → Int
 
 -- Mono
 data Mono
 
 instance Channels Mono where
-    channelFmt _ = c'ESD_MONO
+    channelFmt  _ = c'ESD_MONO
+    numChannels _ = 1
 
 -- Stereo
 data Stereo
 
 instance Channels Stereo where
-    channelFmt _ = c'ESD_STEREO
+    channelFmt  _ = c'ESD_STEREO
+    numChannels _ = 2
 
 {-# INLINE interleave #-}
 interleave ∷ Storable α ⇒ L.Vector α → L.Vector α → L.Vector α
@@ -99,7 +104,7 @@ 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 ()
+failOnError ∷ Monad m ⇒ String → (α → Bool) → α → m α
+failOnError msg isErr rv
+    | isErr rv  = fail msg
+    | otherwise = return rv