X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=top%2Fint.tex;h=a0e0224b8b225b3b7d47b16da493beabec9f52b3;hb=61948f6acce6b49f4612f0c32c3e8728e899628c;hp=7921a9b470897e302714fb648003e07705c28cf5;hpb=a32d07a619a22edaf51648683eedef695d7fb28a;p=phd-thesis.git

diff --git a/top/int.tex b/top/int.tex
index 7921a9b..a0e0224 100644
--- a/top/int.tex
+++ b/top/int.tex
@@ -4,7 +4,6 @@
 
 \begin{document}
 \input{subfileprefix}
-
 \chapter{Integration with \texorpdfstring{\gls{ITASK}}{iTask}}%
 \label{chp:integration_with_itask}
 \begin{chapterabstract}
@@ -27,7 +26,7 @@ The entire system is written as a single \gls{CLEAN} specification where multipl
 Tasks can access \glspl{SDS} according to many-to-many communication and multiple clients can work on the same task.
 Devices are integrated into the system using the \cleaninline{withDevice} function (see \cref{sec:withdevice}).
 Using \cleaninline{liftmTask}, \gls{MTASK} tasks are lifted to a device (see \cref{sec:liftmtask}).
-\Gls{ITASK} \glspl{SDS} are lifted to the \gls{MTASK} device using \cleaninline{liftsds} (see \cref{sec:liftmtask}).
+\Gls{ITASK} \glspl{SDS} are lifted to the \gls{MTASK} device using \cleaninline{liftsds} (see \cref{sec:liftsds}).
 
 \begin{figure}[ht]
 	\centering
@@ -83,9 +82,9 @@ withDevice spec deviceTask =
 	withShared newMap \sdsupdates->
 	withShared ([], [MTTSpecRequest], False) \channels->
 	withShared default \dev->parallel
-		[ channelSync spec
-		, watchForShutdown
-		, watchChannels
+		[ channelSync spec channels
+		, watchForShutdown channels
+		, watchChannelMessages dev channels
 		, waitForSpecification
 			>>| deviceTask
 			>>* [ifStable: issueShutdown]
@@ -117,17 +116,32 @@ liftmTask :: (Main (MTask BCInterpret a)) MTDevice -> Task a | iTask a
 \end{lstClean}
 
 \subsection{Implementation}
-Under the hood, \cleaninline{liftmTask}:
-\begin{itemize}
-	\item Generates a fresh task identifier for the device.
-	\item Compiles the task and fetches the values for the tethered \glspl{SDS}.
-	\item Sends the task to the device
-	\item Watches, in parallel: the tethered \glspl{SDS} in \gls{ITASK}, if they are updated, a message is sent to the device; the \gls{SDS} update queue, if there is a downstream update, the \gls{ITASK} \gls{SDS} it references is updated as well; and the task value.
-\end{itemize}
-
-The task value of the \cleaninline{liftmTask} task is the task value of the task on the edge device.
-
-\todo{v.b.\ voor liftmtask}
+\Cref{lst:liftmTask_pseudo} shows the pseudocode for the \cleaninline{liftmTask} implementation
+The first argument is the task and the second argument is the device which is just an \gls{ADT} containing the \glspl{SDS} referring to the device information, the \gls{SDS} update queue, and the channels.
+First a fresh identifier for the task is generated using the device state.
+With this identifier, the cleanup hook can be installed.
+This is done to assure the task is removed from the edge device if the \gls{ITASK} task coordinating it is destroyed.
+Tasks can be destroyed when for example a task executed in parallel and the parallel combinator terminates or when the condition to step holds in a sequential task combination.
+Then the \gls{MTASK} compiler is invoked, its only argument besides the task is a function doing something with the results of the compilation, i.e.\ the lifted \glspl{SDS} and the messages containing the compiled and serialised task.
+With the result of the compilation, the task can be executed.
+First the messages are put in the channels, sending them to the device.
+Then, in parallel:
+\begin{enumerate*}
+	\item the value is watched by looking in the device state \gls{SDS}, this task also determines the task value of the whole task
+	\item the downstream \glspl{SDS} are monitored, i.e.\ the \cleaninline{sdsupdates} \gls{SDS} is monitored and updates from the device are applied to the associated \gls{ITASK} \gls{SDS}
+	\item the upstroam \glspl{SDS} are monitored by spawning tasks that watch these \glspl{SDS}, if one is updated, the novel value is sent to the edge device.
+\end{enumerate*}
+
+\begin{lstClean}[label={lst:liftmTask_pseudo},caption={Pseudocode implementation for \texttt{liftmTask}.}]
+liftmTask task (MTDevice dev sdsupdates channels)
+	= freshTaskId dev
+	>>= \tid->withCleanupHook (sendmessage [MTTTaskDel tid] channels) (
+		compile task \mrefs msgs->
+			sendMessage msgs channels
+			>>| waitForReturnAndValue tid dev
+			-|| watchSharesDownstream mrefs tid sdsupdates
+			-|| watchSharesUpstream mrefs channels tid)
+\end{lstClean}
 
 \section{Lifting \texorpdfstring{\gls{ITASK}}{iTask} \texorpdfstring{\glsxtrlongpl{SDS}}{shared data sources}}\label{sec:liftsds}
 Lifting \gls{ITASK} \glspl{SDS} to \gls{MTASK} \glspl{SDS} is something that mostly happens at the compiler level using the \cleaninline{liftsds} function (see \cref{lst:mtask_itasksds}).
@@ -143,6 +157,30 @@ class liftsds v where
 		-> Main (MTask v u) | RWShared sds
 \end{lstClean}
 
+As an example, \cref{lst:mtask_liftsds_ex} shows a lightswitch function producing an \imtask{} task.
+Given an \cleaninline{MTDevice} type, a device handle, an \gls{ITASK} \gls{SDS} of the type boolean is created.
+This boolean represents the state of the light.
+The \gls{MTASK} task uses this \gls{SDS} to turn on or off the light.
+An \gls{ITASK} task that runs in parallel allows interactive updating of this state.
+
+\todo{dit voorbeeld aanhouden of alleen die grote gebruiken}
+\begin{lstClean}[label={lst:mtask_liftsds_ex},caption={Interactive light switch program.}]
+lightswitch dev  =
+	withShared False \sh->
+		    liftmTask (mtask sh) dev
+		-|| updateSharedInformation [] sh
+		<<@ Hint "Light switch"
+where
+	mtask sh =
+		declarePin D13 PMOutput \d13->
+		liftsds \ls=sh
+		In fun \f=(\st->
+			     getSds ls
+			>>*. [IfValue ((!=.)st) (\v->writeD d13 v)]
+			>>|. f (Not st))
+		In {main=f true}
+\end{lstClean}
+
 \subsection{Implementation}
 The compilation of the code and the serialisation of the data throws away all typing information.
 \Glspl{SDS} are stored in the compiler state as a map from identifiers to either an initial value or an \cleaninline{MTLens}.
@@ -180,8 +218,6 @@ This identifier is then used to provide a reference to the \cleaninline{def} def
 		}\end{lstClean}
 % VimTeX: SynIgnore off
 
-\todo{v.b.\ voor lifted sdss}
-
 \section{Home automation}
 This section presents a interactive home automation program (\Cref{lst:example_home_automation}) to illustrate \gls{MTASK}'s integration with \gls{ITASK}.
 It consists of a web interface for the user to control which tasks may be executed on either of two connected devices: an \gls{ARDUINO} UNO, connected via a serial port; and an ESP8266 based prototyping board called NodeMCU, connected via \gls{TCP} over WiFi.
@@ -205,7 +241,7 @@ Using the helper function \cleaninline{mkTask}, the actual task is selected from
 For example, when selecting the \cleaninline{temperature} task, the current temperature is shown to the user (\cref{fig:example_screenshots3}).
 This task just sends a simple temperature monitoring task to the device using \cleaninline{liftmTask} and provides a view on its task value using the \cleaninline{>\&>}\footnotemark{} \gls{ITASK} combinator.
 \footnotetext{\cleaninline{(>\&>) infixl 1 :: (Task a) ((SDSLens () (? a) ()) -> Task b) -> Task b \| iTask a \& iTask b}}
-The light switch task at \crefrange{lst:example:ls1}{lst:example:ls2} is a task that has bidirectional interaction.
+The light switch task at \crefrange{lst:example:ls1}{lst:example:ls2} is a task that has bidirectional interaction using the definition of \cleaninline{lightswitch} shown in \cref{lst:mtask_liftsds_ex}.
 Using \cleaninline{liftsds}, the status of the light switch is synchronised with the user.
 The task on the edge device continuously monitors the value of the lifted \gls{SDS}.
 If it is different from the current state, the new value is written to the digital \gls{GPIO} pin 13 and the monitoring function is recursively called.
@@ -232,8 +268,8 @@ If it is different from the current state, the new value is written to the digit
 \end{figure}
 
 \begin{figure}
-	\cleaninputlisting[firstline=12,lastline=60,numbers=left,belowskip=0pt,escapeinside={/*}{*/}]{lst/example.icl}
-	\begin{lstClean}[numbers=left,firstnumber=50,aboveskip=0pt,caption={An example of a home automation program.},label={lst:example_home_automation}]
+	\cleaninputlisting[firstline=12,lastline=50,numbers=left,belowskip=0pt,escapeinside={/*}{*/}]{lst/example.icl}
+	\begin{lstClean}[numbers=left,firstnumber=40,aboveskip=0pt,caption={An example of a home automation program.},label={lst:example_home_automation}]
 	, ...][+\label{lst:example:tasks2}+]\end{lstClean}
 \end{figure}