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/**
* @file
* @author 2012-2013 Stefan Radomski (stefan.radomski@cs.tu-darmstadt.de)
* @copyright Simplified BSD
*
* @cond
* This program is free software: you can redistribute it and/or modify
* it under the terms of the FreeBSD license as published by the FreeBSD
* project.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received a copy of the FreeBSD license along with this
* program. If not, see <http://www.opensource.org/licenses/bsd-license>.
* @endcond
*/
#include "uscxml/Common.h"
#include "InterpreterDraft7.h"
#include <glog/logging.h>
#include "uscxml/UUID.h"
namespace uscxml {
using namespace Arabica::XPath;
using namespace Arabica::DOM;
/**
procedure interpret(doc):
if not valid(doc): failWithError()
expandScxmlSource(doc)
configuration = new OrderedSet()
statesToInvoke = new OrderedSet()
internalQueue = new Queue()
externalQueue = new BlockingQueue()
historyValue = new HashTable()
datamodel = new Datamodel(doc)
if doc.binding == "early":
initializeDatamodel(datamodel, doc)
running = true
executeGlobalScriptElement(doc)
enterStates([doc.initial.transition])
mainEventLoop()
*/
void InterpreterDraft7::interpret() {
if (!_isInitialized)
init();
if (!_scxml)
return;
_sessionId = UUID::getUUID();
std::string datamodelName;
if (datamodelName.length() == 0 && HAS_ATTR(_scxml, "datamodel"))
datamodelName = ATTR(_scxml, "datamodel");
if (datamodelName.length() == 0 && HAS_ATTR(_scxml, "profile")) // SCION SCXML uses profile to specify datamodel
datamodelName = ATTR(_scxml, "profile");
if(datamodelName.length() > 0) {
_dataModel = _factory->createDataModel(datamodelName, this);
} else {
_dataModel = _factory->createDataModel("null", this);
}
if(datamodelName.length() > 0 && !_dataModel) {
LOG(ERROR) << "No datamodel for " << datamodelName << " registered";
}
if (_dataModel) {
_dataModel.assign("_x.args", _cmdLineOptions);
}
setupIOProcessors();
_running = true;
_binding = (HAS_ATTR(_scxml, "binding") && boost::iequals(ATTR(_scxml, "binding"), "late") ? LATE : EARLY);
// @TODO: Reread http://www.w3.org/TR/scxml/#DataBinding
if (_dataModel && _binding == EARLY) {
// initialize all data elements
NodeSet<std::string> dataElems = _xpath.evaluate("//" + _xpathPrefix + "data", _document).asNodeSet();
for (unsigned int i = 0; i < dataElems.size(); i++) {
if (dataElems[i].getNodeType() == Node_base::ELEMENT_NODE)
initializeData(Element<std::string>(dataElems[i]));
}
} else if(_dataModel) {
// initialize current data elements
NodeSet<std::string> topDataElems = filterChildElements(_xmlNSPrefix + "data", filterChildElements(_xmlNSPrefix + "datamodel", _scxml));
for (unsigned int i = 0; i < topDataElems.size(); i++) {
if (topDataElems[i].getNodeType() == Node_base::ELEMENT_NODE)
initializeData(Element<std::string>(topDataElems[i]));
}
}
// executeGlobalScriptElements
NodeSet<std::string> globalScriptElems = _xpath.evaluate("/" + _xpathPrefix + "scxml/" + _xpathPrefix + "script", _document).asNodeSet();
for (unsigned int i = 0; i < globalScriptElems.size(); i++) {
if (_dataModel)
executeContent(globalScriptElems[i]);
}
// initial transition might be implict
NodeSet<std::string> initialTransitions = _xpath.evaluate("/" + _xpathPrefix + "scxml/" + _xpathPrefix + "initial/" + _xpathPrefix + "transition", _document).asNodeSet();
if (initialTransitions.size() == 0) {
Arabica::XPath::NodeSet<std::string> initialStates = getInitialStates();
for (int i = 0; i < initialStates.size(); i++) {
Arabica::DOM::Element<std::string> initialElem = _document.createElementNS(_nsURL, "initial");
initialElem.setAttribute("generated", "true");
Arabica::DOM::Element<std::string> transitionElem = _document.createElementNS(_nsURL, "transition");
transitionElem.setAttribute("target", ATTR(initialStates[i], "id"));
initialElem.appendChild(transitionElem);
_scxml.appendChild(initialElem);
initialTransitions.push_back(transitionElem);
}
}
enterStates(initialTransitions);
// assert(hasLegalConfiguration());
mainEventLoop();
if (_parentQueue) {
// send one final event to unblock eventual listeners
Event quit;
quit.name = "done.state.scxml";
_parentQueue->push(quit);
}
// set datamodel to null from this thread
if(_dataModel)
_dataModel = DataModel();
}
/**
procedure mainEventLoop():
while running:
enabledTransitions = null
macrostepDone = false
# Here we handle eventless transitions and transitions
# triggered by internal events until macrostep is complete
while running and not macrostepDone:
enabledTransitions = selectEventlessTransitions()
if enabledTransitions.isEmpty():
if internalQueue.isEmpty():
macrostepDone = true
else:
internalEvent = internalQueue.dequeue()
datamodel["_event"] = internalEvent
enabledTransitions = selectTransitions(internalEvent)
if not enabledTransitions.isEmpty():
microstep(enabledTransitions.toList())
# either we're in a final state, and we break out of the loop
if not running:
break;
# or we've completed a macrostep, so we start a new macrostep by waiting for an external event
# Here we invoke whatever needs to be invoked. The implementation of 'invoke' is platform-specific
for state in statesToInvoke:
for inv in state.invoke:
invoke(inv)
statesToInvoke.clear()
# Invoking may have raised internal error events and we iterate to handle them
if not internalQueue.isEmpty():
continue
# A blocking wait for an external event. Alternatively, if we have been invoked
# our parent session also might cancel us. The mechanism for this is platform specific,
# but here we assume it’s a special event we receive
externalEvent = externalQueue.dequeue()
if isCancelEvent(externalEvent):
running = false
continue
datamodel["_event"] = externalEvent
for state in configuration:
for inv in state.invoke:
if inv.invokeid == externalEvent.invokeid:
applyFinalize(inv, externalEvent)
if inv.autoforward:
send(inv.id, externalEvent)
enabledTransitions = selectTransitions(externalEvent)
if not enabledTransitions.isEmpty():
microstep(enabledTransitions.toList())
# End of outer while running loop. If we get here, we have reached a top-level final state or have been cancelled
exitInterpreter()
*/
void InterpreterDraft7::mainEventLoop() {
}
/**
procedure exitInterpreter():
statesToExit = configuration.toList().sort(exitOrder)
for s in statesToExit:
for content in s.onexit:
executeContent(content)
for inv in s.invoke:
cancelInvoke(inv)
configuration.delete(s)
if isFinalState(s) and isScxmlState(s.parent):
returnDoneEvent(s.donedata)
*/
void InterpreterDraft7::exitInterpreter() {
}
/**
procedure microstep(enabledTransitions):
exitStates(enabledTransitions)
executeTransitionContent(enabledTransitions)
enterStates(enabledTransitions)
*/
void InterpreterDraft7::microstep(const Arabica::XPath::NodeSet<std::string>& enabledTransitions) {
}
/**
function selectEventlessTransitions():
enabledTransitions = new OrderedSet()
atomicStates = configuration.toList().filter(isAtomicState).sort(documentOrder)
for state in atomicStates:
loop: for s in [state].append(getProperAncestors(state, null)):
for t in s.transition:
if not t.event and conditionMatch(t):
enabledTransitions.add(t)
break loop
enabledTransitions = filterPreempted(enabledTransitions)
return enabledTransitions
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::selectEventlessTransitions() {
return Arabica::XPath::NodeSet<std::string>();
}
/**
function selectTransitions(event):
enabledTransitions = new OrderedSet()
atomicStates = configuration.toList().filter(isAtomicState).sort(documentOrder)
for state in atomicStates:
loop: for s in [state].append(getProperAncestors(state, null)):
for t in s.transition:
if t.event and nameMatch(t.event, event.name) and conditionMatch(t):
enabledTransitions.add(t)
break loop
enabledTransitions = removeConflictingTransitions(enabledTransitions)
return enabledTransitions
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::selectTransitions(const std::string& event) {
return Arabica::XPath::NodeSet<std::string>();
}
/**
procedure enterStates(enabledTransitions):
statesToEnter = new OrderedSet()
statesForDefaultEntry = new OrderedSet()
computeEntrySet(enabledTransitions, statesToEnter, statesForDefaultEntry)
for s in statesToEnter.toList().sort(entryOrder):
configuration.add(s)
statesToInvoke.add(s)
if binding == "late" and s.isFirstEntry:
initializeDataModel(datamodel.s,doc.s)
s.isFirstEntry = false
for content in s.onentry:
executeContent(content)
if statesForDefaultEntry.isMember(s):
executeContent(s.initial.transition)
if isFinalState(s):
if isSCXMLElement(s.parent):
running = false
else:
parent = s.parent
grandparent = parent.parent
internalQueue.enqueue(new Event("done.state." + parent.id, s.donedata))
if isParallelState(grandparent):
if getChildStates(grandparent).every(isInFinalState):
internalQueue.enqueue(new Event("done.state." + grandparent.id))
*/
void InterpreterDraft7::enterStates(const Arabica::XPath::NodeSet<std::string>& enabledTransitions) {
}
/**
procedure exitStates(enabledTransitions):
statesToExit = computeExitSet(enabledTransitions)
for s in statesToExit:
statesToInvoke.delete(s)
statesToExit = statesToExit.toList().sort(exitOrder)
for s in statesToExit:
for h in s.history:
if h.type == "deep":
f = lambda s0: isAtomicState(s0) and isDescendant(s0,s)
else:
f = lambda s0: s0.parent == s
historyValue[h.id] = configuration.toList().filter(f)
for s in statesToExit:
for content in s.onexit:
executeContent(content)
for inv in s.invoke:
cancelInvoke(inv)
configuration.delete(s)
*/
void InterpreterDraft7::exitStates(const Arabica::XPath::NodeSet<std::string>& enabledTransitions) {
}
/**
function computeExitSet(transitions)
statesToExit = new OrderedSet
for t in transitions:
domain = getTransitionDomain(t)
for s in configuration:
if isDescendant(s,domain):
statesToExit.add(s)
return statesToExit
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::computeExitSet(const Arabica::XPath::NodeSet<std::string>& enabledTransitions,
const Arabica::XPath::NodeSet<std::string>& statesToExit) {
return Arabica::XPath::NodeSet<std::string>();
}
/**
procedure computeEntrySet(transitions, statesToEnter, statesForDefaultEntry)
for t in transitions:
statesToEnter.union(getTargetStates(t.target))
for s in statesToEnter:
addDescendentStatesToEnter(s,statesToEnter,statesForDefaultEntry)
for t in transitions:
ancestor = getTransitionDomain(t)
for s in getTargetStates(t.target)):
addAncestorStatesToEnter(s, ancestor, statesToEnter, statesForDefaultEntry)
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::computeEntrySet(const Arabica::XPath::NodeSet<std::string>& transitions,
const Arabica::XPath::NodeSet<std::string>& statesToEnter,
const Arabica::XPath::NodeSet<std::string>& statesForDefaultEntry) {
return Arabica::XPath::NodeSet<std::string>();
}
/**
function removeConflictingTransitions(enabledTransitions):
filteredTransitions = new OrderedSet()
// toList sorts the transitions in the order of the states that selected them
for t1 in enabledTransitions.toList():
t1Preempted = false;
transitionsToRemove = new OrderedSet()
for t2 in filteredTransitions.toList():
if computeExitSet(t1).hasIntersection(computeExitSet(t2)):
if isDescendent(t1.source, t2.source):
transitionsToRemove.add(t2)
else:
t1Preempted = true
break
if not t1Preempted:
for t3 in transitionsToRemove.toList():
filteredTransitions.delete(t3)
filteredTransitions.add(t1)
return filteredTransitions
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::removeConflictingTransitions(const Arabica::XPath::NodeSet<std::string>& enabledTransitions) {
return Arabica::XPath::NodeSet<std::string>();
}
/**
function getTransitionDomain(t)
tstates = getTargetStates(t.target)
if not tstates
return t.source
elif t.type == "internal" and isCompoundState(t.source) and tstates.every(lambda s: isDescendant(s,t.source)):
return t.source
else:
return findLCCA([t.source].append(tstates))
*/
Arabica::DOM::Node<std::string> InterpreterDraft7::getTransitionDomain(const Arabica::DOM::Node<std::string>& transition) {
return Arabica::DOM::Node<std::string>();
}
/**
procedure addDescendentStatesToEnter(state,statesToEnter,statesForDefaultEntry):
if isHistoryState(state):
if historyValue[state.id]:
for s in historyValue[state.id]:
addDescendentStatesToEnter(s,statesToEnter,statesForDefaultEntry)
addAncestorStatesToEnter(s, state.parent, statesToEnter, statesForDefaultEntry)
else:
for t in state.transition:
for s in getTargetStates(t.target):
addDescendentStatesToEnter(s,statesToEnter,statesForDefaultEntry)
addAncestorStatesToEnter(s, state.parent, statesToEnter, statesForDefaultEntry)
else:
statesToEnter.add(state)
if isCompoundState(state):
statesForDefaultEntry.add(state)
for s in getTargetStates(state.initial):
addDescendentStatesToEnter(s,statesToEnter,statesForDefaultEntry)
addAncestorStatesToEnter(s, state, statesToEnter, statesForDefaultEntry)
else:
if isParallelState(state):
for child in getChildStates(state):
if not statesToEnter.some(lambda s: isDescendant(s,child)):
addDescendentStatesToEnter(child,statesToEnter,statesForDefaultEntry)
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::addDescendentStatesToEnter(const Arabica::DOM::Node<std::string>& state,
const Arabica::XPath::NodeSet<std::string>& statesToEnter,
const Arabica::XPath::NodeSet<std::string>& statesForDefaultEntry) {
return Arabica::XPath::NodeSet<std::string>();
}
/**
procedure addAncestorsToEnter(state, ancestor, statesToEnter, statesForDefaultEntry)
for anc in getProperAncestors(state,ancestor):
statesToEnter.add(anc)
if isParallelState(anc):
for child in getChildStates(anc):
if not statesToEnter.some(lambda s: isDescendant(s,child)):
addStatesToEnter(child,statesToEnter,statesForDefaultEntry)
*/
Arabica::XPath::NodeSet<std::string> InterpreterDraft7::addAncestorsStatesToEnter(const Arabica::DOM::Node<std::string>& state,
const Arabica::DOM::Node<std::string>& ancestor,
const Arabica::XPath::NodeSet<std::string>& statesToEnter,
const Arabica::XPath::NodeSet<std::string>& statesForDefaultEntry) {
return Arabica::XPath::NodeSet<std::string>();
}
}
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