blob: b5ee80eb6479bd70da21f36d6f929db9d3d300d1 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
module Fig.Utils.FFI where
import Fig.Prelude
import Foreign.Ptr (Ptr, nullPtr)
import Foreign.Storable (Storable(..))
import Foreign.C.String
import Foreign.Marshal.Alloc
foreign import ccall "check_answer" c_check_answer :: Ptr CString -> CString -> CString -> IO Int
checkAnswer :: Text -> Text -> IO (Either Text Bool)
checkAnswer tcode tanswer =
withCString (unpack tcode) $ \code ->
withCString (unpack tanswer) $ \answer ->
alloca $ \rerr -> do
res <- c_check_answer rerr code answer
err <- peek rerr
if err == nullPtr
then pure . Right $ res /= 0
else do
msg <- peekCString err
pure . Left $ pack msg
|