Remove HID counter and HIDs; extract common searchHandlers function
This commit is contained in:
Tony Garnock-Jones
parent
a4113f7608
commit
1dcf34bd56
82
os.hs
82
os.hs
|
|
@ -1,41 +1,34 @@
|
|||
{-# LANGUAGE ExistentialQuantification #-}
|
||||
-- MultiParamTypeClasses FunctionalDependencies
|
||||
module OS where
|
||||
|
||||
-- TODO try avoiding double-matching for metamessages by closing over the callback
|
||||
-- TODO try using PIDs instead of HIDs to avoid the search in runMetaHandler
|
||||
-- TODO try avoiding double-matching for metamessages and the need for
|
||||
-- broadcast by introducing a facility for supporting event-pattern
|
||||
-- subtyping
|
||||
|
||||
import Data.IntMap (IntMap)
|
||||
import qualified Data.IntMap as IntMap
|
||||
import Control.Arrow ((>>>))
|
||||
import Data.Maybe
|
||||
import Data.List
|
||||
import Control.Concurrent.Chan
|
||||
|
||||
data VM m mm = VM { hidCounter :: Int,
|
||||
suspensions :: [Suspension m mm],
|
||||
data VM m mm = VM { suspensions :: [Suspension m mm],
|
||||
messages :: [m],
|
||||
metaMessages :: [mm],
|
||||
runnables :: [Callback m mm ()] }
|
||||
type Callback m mm state = (state -> KernelModeTransition m mm)
|
||||
data Subscription m mm = forall state. Subscription
|
||||
state
|
||||
(Maybe (Callback m mm state))
|
||||
[Handler m mm state]
|
||||
[MetaHandler m mm state]
|
||||
data Suspension m mm = forall state. Suspension
|
||||
state
|
||||
(Maybe (Callback m mm state))
|
||||
[Handler m mm state]
|
||||
(IntMap (MetaHandler m mm state))
|
||||
data KernelModeTransition m mm = KernelModeTransition (Subscription m mm)
|
||||
[MetaHandler m mm state]
|
||||
data KernelModeTransition m mm = KernelModeTransition (Suspension m mm)
|
||||
[m]
|
||||
[mm]
|
||||
[Callback m mm ()]
|
||||
type HID = Int
|
||||
type Handler m mm state = (m -> Maybe (Callback m mm state))
|
||||
type MetaHandler m mm state = (mm -> Maybe (Callback m mm state))
|
||||
|
||||
newVM boot = VM { hidCounter = 0,
|
||||
suspensions = [],
|
||||
newVM boot = VM { suspensions = [],
|
||||
messages = [],
|
||||
metaMessages = [],
|
||||
runnables = [boot] }
|
||||
|
|
@ -46,7 +39,7 @@ runVM = rebuildSuspensions enqueuePoller >>> runRunnables >>> dispatchMessages >
|
|||
mmhs = concatMap extractDown $ suspensions vm
|
||||
pollerK = if shouldPoll vm then Just runVM else Nothing
|
||||
in
|
||||
KernelModeTransition (Subscription (vm { metaMessages = [] }) pollerK mmhs []) mms [] []
|
||||
KernelModeTransition (Suspension (vm { metaMessages = [] }) pollerK mmhs []) mms [] []
|
||||
|
||||
rebuildSuspensions :: (VM m mm -> Suspension m mm -> VM m mm) -> (VM m mm) -> (VM m mm)
|
||||
rebuildSuspensions f vm = foldl f (vm { suspensions = [] }) (suspensions vm)
|
||||
|
|
@ -66,21 +59,19 @@ dispatchMessages vm = foldr dispatchMessage (vm { messages = [] }) (messages vm)
|
|||
|
||||
dispatchMessage m = rebuildSuspensions matchSuspension
|
||||
where matchSuspension vm susp@(Suspension state _ mhs _) =
|
||||
let searchHandlers [] = vm { suspensions = susp : suspensions vm }
|
||||
searchHandlers (mh:mhs) =
|
||||
case mh m of
|
||||
Just h -> performTransition (h state) vm
|
||||
Nothing -> searchHandlers mhs
|
||||
in searchHandlers mhs
|
||||
searchHandlers vm susp state m mhs
|
||||
|
||||
extractDown (Suspension _ _ _ mmhs) =
|
||||
IntMap.foldWithKey (\ hid mmh xs -> dispatchMetaMessage hid mmh : xs) [] mmhs
|
||||
searchHandlers vm susp state m [] = vm { suspensions = susp : suspensions vm }
|
||||
searchHandlers vm susp state m (mh:mhs) =
|
||||
case mh m of
|
||||
Just h -> performTransition (h state) vm
|
||||
Nothing -> searchHandlers vm susp state m mhs
|
||||
|
||||
dispatchMetaMessage :: HID -> MetaHandler m mm state -> Handler mm mm1 (VM m mm)
|
||||
dispatchMetaMessage hid mmh mm =
|
||||
case mmh mm of
|
||||
Nothing -> Nothing
|
||||
Just _ -> Just (runMetaHandler hid mm)
|
||||
extractDown (Suspension _ _ _ mmhs) = map matchMetaMessage mmhs
|
||||
where matchMetaMessage mmh mm =
|
||||
case mmh mm of
|
||||
Nothing -> Nothing
|
||||
Just _ -> Just (runMetaHandler mm)
|
||||
|
||||
isPolling (Suspension _ pollerK _ _) = isNothing pollerK
|
||||
isBlocked = not . isPolling
|
||||
|
|
@ -88,29 +79,20 @@ isBlocked = not . isPolling
|
|||
shouldPoll vm@(VM { messages = [], runnables = []}) = not $ all isBlocked (suspensions vm)
|
||||
shouldPoll _ = True
|
||||
|
||||
runMetaHandler :: HID -> mm -> (VM m mm) -> (KernelModeTransition mm mm1)
|
||||
runMetaHandler hid mm = runVM . rebuildSuspensions runHid
|
||||
where runHid vm susp@(Suspension state _ _ mmhs) =
|
||||
case IntMap.lookup hid mmhs of
|
||||
Just h -> performTransition ((fromJust $ h mm) state) vm
|
||||
Nothing -> vm { suspensions = susp : suspensions vm }
|
||||
|
||||
addHids vm mmhs =
|
||||
foldr (\ mmh (vm, acc) -> let h = hidCounter vm in
|
||||
(vm { hidCounter = h + 1 }, IntMap.insert h mmh acc))
|
||||
(vm, IntMap.empty)
|
||||
mmhs
|
||||
runMetaHandler :: mm -> (VM m mm) -> (KernelModeTransition mm mm1)
|
||||
runMetaHandler mm = runVM . rebuildSuspensions dispatchMetaMessage
|
||||
where dispatchMetaMessage vm susp@(Suspension state _ _ mmhs) =
|
||||
searchHandlers vm susp state mm mmhs
|
||||
|
||||
performTransition :: KernelModeTransition m mm -> VM m mm -> VM m mm
|
||||
performTransition (KernelModeTransition (Subscription state pollerK mhs mmhs) ms mms cbs) vm =
|
||||
let (vm, hidMap) = addHids vm mmhs in
|
||||
vm { suspensions = (Suspension state pollerK mhs hidMap) : suspensions vm,
|
||||
performTransition (KernelModeTransition susp ms mms cbs) vm =
|
||||
vm { suspensions = susp : suspensions vm,
|
||||
messages = reverse ms ++ (messages vm),
|
||||
metaMessages = reverse mms ++ (metaMessages vm),
|
||||
runnables = reverse cbs ++ (runnables vm) }
|
||||
|
||||
---------------------------------------------------------------------------
|
||||
|
||||
{-
|
||||
type LabelledMessage a b = (a, b)
|
||||
|
||||
groundVM :: Callback m (IO ()) () -> IO ()
|
||||
|
|
@ -146,4 +128,10 @@ groundVM boot = do inboundChannel <- newChan
|
|||
(loop ((inbound-continuation inbound-value) new-state))]
|
||||
[_
|
||||
(error 'ground-vm
|
||||
"Outermost VM may not spawn new siblings or send or receive metamessages")]))))
|
||||
"Outermost VM may not spawn new siblings or send or receive metamessages")]))))
|
||||
-}
|
||||
|
||||
-- -- Values of type v are matchable by values of type p, yielding
|
||||
-- -- residuals of type a.
|
||||
-- class Matchable v p a | v -> p where
|
||||
-- match :: p -> v -> Maybe a
|
||||
|
|
|
|||
Loading…
Reference in New Issue