{-# LANGUAGE TypeSynonymInstances #-}

{- |

Module : ./Common/MathLink.hs

Description : A Haskell MathLink interface

Copyright : (c) Ewaryst Schulz, DFKI Bremen 2011

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Ewaryst.Schulz@dfki.de

Stability : experimental

Portability : non-portable (see language extensions)

A Haskell MathLink interface based on the Foreign.MathLink.Bindings module

-}

module Common.MathLink where

import Foreign.C -- get the C types

import Foreign.Marshal -- get the array marshalling utils

import Foreign.Storable

import Foreign.Ptr (Ptr, nullPtr)

import Foreign.MathLink.Bindings

import Control.Monad.Reader

import System.Timeout

import System.IO

import Data.Maybe

import Common.Utils (verbMsg, verbMsgLn, verbMsgIOLn)

-- * Constants for the MathLink interface

dfMLTKAEND, dfMLTKALL_DECODERS, dfMLTKAPCTEND, dfMLTKARRAY,

dfMLTKARRAY_DECODER , dfMLTKCONT, dfMLTKDIM, dfMLTKELEN, dfMLTKEND,

dfMLTKERR, dfMLTKERROR , dfMLTKFUNC, dfMLTKINT,

dfMLTKMODERNCHARS_DECODER, dfMLTKNULL , dfMLTKNULLSEQUENCE_DECODER,

dfMLTKOLDINT, dfMLTKOLDREAL, dfMLTKOLDSTR , dfMLTKOLDSYM,

dfMLTKPACKED_DECODER, dfMLTKPACKED, dfMLTKPCTEND, dfMLTKREAL ,

dfMLTKSEND, dfMLTKSTR, dfMLTKSYM, dfILLEGALPKT, dfCALLPKT,

dfEVALUATEPKT , dfRETURNPKT, dfINPUTNAMEPKT, dfENTERTEXTPKT,

dfENTEREXPRPKT, dfOUTPUTNAMEPKT, dfRETURNTEXTPKT, dfRETURNEXPRPKT,

dfDISPLAYPKT, dfDISPLAYENDPKT, dfMESSAGEPKT, dfTEXTPKT, dfINPUTPKT,

dfINPUTSTRPKT, dfMENUPKT, dfSYNTAXPKT, dfSUSPENDPKT, dfRESUMEPKT,

dfBEGINDLGPKT, dfENDDLGPKT, dfFIRSTUSERPKT, dfLASTUSERPKT :: CInt

dfILLEGALPKT = 0

dfCALLPKT = 7

dfEVALUATEPKT = 13

dfRETURNPKT = 3

dfINPUTNAMEPKT = 8

dfENTERTEXTPKT = 14

dfENTEREXPRPKT = 15

dfOUTPUTNAMEPKT = 9

dfRETURNTEXTPKT = 4

dfRETURNEXPRPKT = 16

dfDISPLAYPKT = 11

dfDISPLAYENDPKT = 12

dfMESSAGEPKT = 5

dfTEXTPKT = 2

dfINPUTPKT = 1

dfINPUTSTRPKT = 21

dfMENUPKT = 6

dfSYNTAXPKT = 10

dfSUSPENDPKT = 17

dfRESUMEPKT = 18

dfBEGINDLGPKT = 19

dfENDDLGPKT = 20

dfFIRSTUSERPKT = 128

dfLASTUSERPKT = 255

dfMLTKAEND = 13

dfMLTKALL_DECODERS = 983040

dfMLTKAPCTEND = 10

dfMLTKARRAY = 65

dfMLTKARRAY_DECODER = 262144

dfMLTKCONT = 92

dfMLTKDIM = 68

dfMLTKELEN = 32

dfMLTKEND = 10

dfMLTKERR = 0

dfMLTKERROR = 0

dfMLTKFUNC = 70

dfMLTKINT = 43

dfMLTKMODERNCHARS_DECODER = 524288

dfMLTKNULL = 46

dfMLTKNULLSEQUENCE_DECODER = 0

dfMLTKOLDINT = 73

dfMLTKOLDREAL = 82

dfMLTKOLDSTR = 83

dfMLTKOLDSYM = 89

dfMLTKPACKED_DECODER = 131072

dfMLTKPACKED = 80

dfMLTKPCTEND = 93

dfMLTKREAL = 42

dfMLTKSEND = 44

dfMLTKSTR = 34

dfMLTKSYM = 35

showPKT :: CInt -> String

showPKT i | i == dfILLEGALPKT = "ILLEGALPKT"

| i == dfCALLPKT = "CALLPKT"

| i == dfEVALUATEPKT = "EVALUATEPKT"

| i == dfRETURNPKT = "RETURNPKT"

| i == dfINPUTNAMEPKT = "INPUTNAMEPKT"

| i == dfENTERTEXTPKT = "ENTERTEXTPKT"

| i == dfENTEREXPRPKT = "ENTEREXPRPKT"

| i == dfOUTPUTNAMEPKT = "OUTPUTNAMEPKT"

| i == dfRETURNTEXTPKT = "RETURNTEXTPKT"

| i == dfRETURNEXPRPKT = "RETURNEXPRPKT"

| i == dfDISPLAYPKT = "DISPLAYPKT"

| i == dfDISPLAYENDPKT = "DISPLAYENDPKT"

| i == dfMESSAGEPKT = "MESSAGEPKT"

| i == dfTEXTPKT = "TEXTPKT"

| i == dfINPUTPKT = "INPUTPKT"

| i == dfINPUTSTRPKT = "INPUTSTRPKT"

| i == dfMENUPKT = "MENUPKT"

| i == dfSYNTAXPKT = "SYNTAXPKT"

| i == dfSUSPENDPKT = "SUSPENDPKT"

| i == dfRESUMEPKT = "RESUMEPKT"

| i == dfBEGINDLGPKT = "BEGINDLGPKT"

| i == dfENDDLGPKT = "ENDDLGPKT"

| i == dfFIRSTUSERPKT = "FIRSTUSERPKT"

| i == dfLASTUSERPKT = "LASTUSERPKT"

| otherwise = "UNRECOGNIZED PACKET"

showTK :: CInt -> String

showTK i | i == dfMLTKAEND = "MLTKAEND"

| i == dfMLTKALL_DECODERS = "MLTKALL_DECODERS"

| i == dfMLTKAPCTEND = "MLTKAPCTEND"

| i == dfMLTKARRAY = "MLTKARRAY"

| i == dfMLTKARRAY_DECODER = "MLTKARRAY_DECODER"

| i == dfMLTKCONT = "MLTKCONT"

| i == dfMLTKDIM = "MLTKDIM"

| i == dfMLTKELEN = "MLTKELEN"

| i == dfMLTKEND = "MLTKEND"

| i == dfMLTKERR = "MLTKERR"

| i == dfMLTKERROR = "MLTKERROR"

| i == dfMLTKFUNC = "MLTKFUNC"

| i == dfMLTKINT = "MLTKINT"

| i == dfMLTKMODERNCHARS_DECODER = "MLTKMODERNCHARS_DECODER"

| i == dfMLTKNULL = "MLTKNULL"

| i == dfMLTKNULLSEQUENCE_DECODER = "MLTKNULLSEQUENCE_DECODER"

| i == dfMLTKOLDINT = "MLTKOLDINT"

| i == dfMLTKOLDREAL = "MLTKOLDREAL"

| i == dfMLTKOLDSTR = "MLTKOLDSTR"

| i == dfMLTKOLDSYM = "MLTKOLDSYM"

| i == dfMLTKPACKED_DECODER = "MLTKPACKED_DECODER"

| i == dfMLTKPACKED = "MLTKPACKED"

| i == dfMLTKPCTEND = "MLTKPCTEND"

| i == dfMLTKREAL = "MLTKREAL"

| i == dfMLTKSEND = "MLTKSEND"

| i == dfMLTKSTR = "MLTKSTR"

| i == dfMLTKSYM = "MLTKSYM"

| otherwise = "UNRECOGNIZED TK"

-- * MathLink monad as Reader IO monad

data MLState =

MLState

{ mlink :: MLINK

, menv :: MLEnvironment

, mverbosity :: Int

, logHdl :: Maybe Handle

}

type ML = ReaderT MLState IO

-- | Prints a message dependent on the verbosity level

verbMsgML :: Int -> String -> ML ()

verbMsgML lvl msg = do

hdl <- getHandle

v <- asks mverbosity

liftIO $ verbMsg hdl v lvl msg

-- | Prints a message dependent on the verbosity level

verbMsgMLLn :: Int -> String -> ML ()

verbMsgMLLn lvl msg = do

hdl <- getHandle

v <- asks mverbosity

liftIO $ verbMsgLn hdl v lvl msg

getHandle :: ML Handle

getHandle = liftM (fromMaybe stdout) $ asks logHdl

mkState :: MLINK -> MLEnvironment -> Int -> MLState

mkState mlp env v = MLState { mlink = mlp, menv = env, mverbosity = v

, logHdl = Nothing }

addLogging :: MLState -> Handle -> MLState

addLogging st hdl = st { logHdl = Just hdl }

askMLink :: ML MLINK

askMLink = asks mlink

liftMLIO :: (MLINK -> IO b) -> ML b

liftMLIO f = askMLink >>= liftIO . f

-- * MathLink connection handling

-- | Open connection to MathLink or return error code on failure

openLink :: Int -- ^ Verbosity

-> Maybe String {- ^ Connection name

(launches a new kernel if not specified) -}

-> IO (Either Int MLState)

openLink v mName = do

env <- cMlInitialize nullPtr

if env == nullPtr then return $ Left 1

else do

verbMsgIOLn v 2 "Initialized"

let (name, mode) = case mName of

Just n -> (n, "connect")

_ -> ("math -mathlink", "launch")

let openargs = ["-linkname", name, "-linkmode", mode]

lp <- mlOpen 4 openargs

mB <- if lp == nullPtr then return Nothing

-- else liftM Just $ connectLink lp

else timeout 3000000 $ connectLink lp v

case mB of

Nothing -> return $ Left 2

Just False -> return $ Left 3

_ -> return $ Right $ mkState lp env v

-- | Close connection to MathLink

closeLink :: MLState -> IO ()

closeLink st = do

mlClose $ mlink st

cMlDeinitialize $ menv st

-- | Run ML-program on an opened connection to MathLink

withLink :: MLState -- ^ MathLink connection

-> Maybe FilePath -- ^ Log low level messages into this file (or STDOUT)

-> ML a -- ^ The program to run

-> IO a

withLink st mFp mlprog =

case mFp of

Just fp ->

withFile fp WriteMode $ runReaderT mlprog . addLogging st

Nothing ->

runReaderT mlprog st

{- | Run ML-program on a new connection to MathLink which is closed right

after the execution and return the prgram result or error code on failure -}

runLink :: Maybe FilePath -- ^ Log low level messages into this file (or STDOUT)

-> Int -- ^ Verbosity

-> Maybe String {- ^ Connection name

(launches a new kernel if not specified) -}

-> ML a -- ^ The program to run

-> IO (Either Int a)

runLink mFp v mName mlprog = do

eSt <- openLink v mName

case eSt of

Left i -> return $ Left i

Right st ->

do

verbMsgIOLn v 2 "Opened"

x <- withLink st mFp mlprog

closeLink st

return $ Right x

-- | Low level: open connection

mlOpen :: CInt -> [String] -> IO MLINK

mlOpen i l = withStringArray l $ cMlOpen i

-- | Low level: check connection

connectLink :: MLINK

-> Int -- ^ Verbosity

-> IO Bool

connectLink lp v = do

let p i j = do

i' <- cMlReady lp

if toBool i' || j > 3000 then return j

else cMlFlush lp >> if i > 1000 then p 0 (j + 1) else p (i + 1) j

p (0 :: Int) (0 :: Int) >>= verbMsgIOLn v 2 . ("ready after " ++) . show

res <- cMlConnect lp

return $ toBool res

-- | Low level: close connection

mlClose :: MLINK -> IO CInt

mlClose = cMlClose

-- * C to Haskell utilities

withStringArray :: MonadIO m => [String] -> (Ptr CString -> IO b) -> m b

withStringArray l f = liftIO $ mapM newCString l >>= flip withArray f

mlGetA :: (Storable a, Show a, Show b) => (Ptr a -> IO b) -> IO a

mlGetA f = let g ptr = f ptr >> peek ptr in alloca g

-- TODO: maybe better via foreign pointer, check later

mlGetCString :: Show b => (Ptr CString -> IO b) -> (CString -> IO ()) -> IO String

mlGetCString f disownF =

let g ptr = do

cs <- f ptr >> peek ptr

s <- peekCString cs

disownF cs

return s

in alloca g

-- * C Type conversions

cintToInteger :: CInt -> Integer

cintToInteger = fromIntegral

intToCInt :: Int -> CInt

intToCInt = fromIntegral

-- | This function is unsafe, it may overflow...

cintToInt :: CInt -> Int

cintToInt = fromIntegral

cdblToDbl :: CDouble -> Double

cdblToDbl = realToFrac

dblToCDbl :: Double -> CDouble

dblToCDbl = realToFrac

-- * MathLink interface using the ML monad, built on top of the raw bindings

mlFlush :: ML CInt

mlFlush = liftMLIO cMlFlush

mlReady :: ML CInt

mlReady = liftMLIO cMlReady

mlConnect :: ML CInt

mlConnect = liftMLIO cMlConnect

mlEndPacket :: ML CInt

mlEndPacket = liftMLIO cMlEndPacket

mlNextPacket :: ML CInt

mlNextPacket = liftMLIO cMlNextPacket

mlNewPacket :: ML CInt

mlNewPacket = liftMLIO cMlNewPacket

mlGetNext :: ML CInt

mlGetNext = liftMLIO cMlGetNext

mlGetArgCount :: ML CInt

mlGetArgCount = askMLink >>= liftIO . mlGetA . cMlGetArgCount

mlGetArgCount' :: ML Int

mlGetArgCount' = liftM cintToInt mlGetArgCount

-- cMlGetSymbol :: MLINK -> Ptr CString -> IO CInt

mlGetSymbol :: ML String

mlGetSymbol = do

ml <- askMLink

liftIO $ mlGetCString (cMlGetSymbol ml) $ cMlDisownSymbol ml

-- cMlGetString :: MLINK -> Ptr CString -> IO CInt

mlGetString :: ML String

-- mlGetString = askMLink >>= liftIO . mlGetCString . cMlGetString

mlGetString = do

ml <- askMLink

liftIO $ mlGetCString (cMlGetString ml) $ cMlDisownString ml

-- cMlGetReal :: MLINK -> Ptr CDouble -> IO CInt

mlGetReal :: ML CDouble

mlGetReal = askMLink >>= liftIO . mlGetA . cMlGetReal

mlGetReal' :: ML Double

mlGetReal' = liftM cdblToDbl mlGetReal

-- cMlGetInteger :: MLINK -> Ptr CInt -> IO CInt

mlGetInteger :: ML CInt

mlGetInteger = askMLink >>= liftIO . mlGetA . cMlGetInteger

mlGetInteger' :: ML Int

mlGetInteger' = liftM cintToInt mlGetInteger

{- | Integers are received as strings, because the interface supports only

machine integers with fixed length not arbitrary sized integers. -}

mlGetInteger'' :: ML Integer

mlGetInteger'' = liftM read mlGetString

mlPutString :: String -> ML CInt

mlPutString s = liftMLIO f where

f ml = withCString s $ cMlPutString ml

mlPutSymbol :: String -> ML CInt

mlPutSymbol s = liftMLIO f where

f ml = withCString s $ cMlPutSymbol ml

mlPutFunction :: String -> CInt -> ML CInt

mlPutFunction s i = liftMLIO f where

f ml = withCString s $ flip (cMlPutFunction ml) i

mlPutFunction' :: String -> Int -> ML CInt

mlPutFunction' s = mlPutFunction s . intToCInt

mlPutInteger :: CInt -> ML CInt

mlPutInteger = liftMLIO . flip cMlPutInteger

mlPutInteger' :: Int -> ML CInt

mlPutInteger' = mlPutInteger . intToCInt

{- | Integers are sent as strings, because the interface supports only

machine integers with fixed length not arbitrary sized integers. -}

mlPutInteger'' :: Integer -> ML CInt

mlPutInteger'' i = mlPutFunction' "ToExpression" 1 >> mlPutString (show i)

mlPutReal :: CDouble -> ML CInt

mlPutReal = liftMLIO . flip cMlPutReal

mlPutReal' :: Double -> ML CInt

mlPutReal' = mlPutReal . dblToCDbl

mlError :: ML CInt

mlError = liftMLIO cMlError

mlErrorMessage :: ML String

mlErrorMessage = liftMLIO (cMlErrorMessage >=> peekCString)

-- * MathLink interface utils

mlProcError :: ML a

mlProcError = do

eid <- mlError

s <- if toBool eid then liftM ("Error detected by MathLink: " ++)

mlErrorMessage

else return "Error detected by Interface"

verbMsgMLLn 1 s

error $ "mlProcError: " ++ s

sendEvalPacket :: ML a -> ML a

sendEvalPacket ml = do

mlPutFunction "EvaluatePacket" 1

res <- ml

mlEndPacket

return res

sendTextPacket :: String -> ML ()

sendTextPacket s = do

mlPutFunction "EvaluatePacket" 1

mlPutFunction "ToExpression" 1

mlPutString s

mlEndPacket

return ()

sendTextResultPacket :: String -> ML ()

sendTextResultPacket s = do

mlPutFunction "EvaluatePacket" 1

mlPutFunction "ToString" 1

mlPutFunction "ToExpression" 1

mlPutString s

mlEndPacket

return ()

{-

-- these variants does not work as expected

sendTextPacket' :: String -> ML ()

sendTextPacket' s = do

mlPutFunction "EnterTextPacket" 1

mlPutString s

mlEndPacket

return ()

sendTextPacket'' :: String -> ML ()

sendTextPacket'' s = do

mlPutFunction "EnterExpressionPacket" 1

mlPutFunction "ToExpression" 1

mlPutString s

mlEndPacket

return ()

sendTextPacket3 :: String -> ML ()

sendTextPacket3 s = do

mlPutFunction "EvaluatePacket" 1

mlPutFunction "ToString" 1

mlPutFunction "ToExpression" 1

mlPutString s

mlEndPacket

return ()

sendTextPacket4 :: String -> ML ()

sendTextPacket4 s = do

mlPutFunction "EnterExpressionPacket" 1

mlPutFunction "ToString" 1

mlPutFunction "ToExpression" 1

mlPutString s

mlEndPacket

return ()

-}

waitForAnswer :: ML CInt

waitForAnswer = do

-- skip any packets before the first ReturnPacket

i <- waitUntilPacket (0 :: Int) [ dfRETURNPKT, dfRETURNEXPRPKT

, dfRETURNTEXTPKT, dfILLEGALPKT]

if elem i [dfILLEGALPKT, dfRETURNEXPRPKT, dfRETURNTEXTPKT]

then error $ "waitForAnswer: encountered a " ++ showPKT i

else return i

-- wait for the answer and skip it

skipAnswer :: ML CInt

skipAnswer = waitForAnswer >> mlNewPacket

waitUntilPacket :: Num a => a -> [CInt] -> ML CInt

waitUntilPacket i l = do

np <- mlNextPacket

if elem np l then do

verbMsgMLLn 2 $ "GotReturn after " ++ show i ++ " iterations"

return np

else verbMsgMLLn 2 ("wap: " ++ show np) >> mlNewPacket

>> waitUntilPacket (i + 1) l