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Diffstat (limited to 'src/uscxml/interpreter/InterpreterDraft7.cpp')
| -rw-r--r-- | src/uscxml/interpreter/InterpreterDraft7.cpp | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/src/uscxml/interpreter/InterpreterDraft7.cpp b/src/uscxml/interpreter/InterpreterDraft7.cpp new file mode 100644 index 0000000..9542146 --- /dev/null +++ b/src/uscxml/interpreter/InterpreterDraft7.cpp @@ -0,0 +1,439 @@ +#include "InterpreterDraft7.h" + +#include <glog/logging.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 = 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); + if(datamodelName.length() > 0 && !_dataModel) { + LOG(ERROR) << "No datamodel for " << datamodelName << " registered"; + } + + if (_dataModel) { + _dataModel.assign("_x.args", _cmdLineOptions); + if (_httpServlet) { + Data data; + data.compound["location"] = Data(_httpServlet->getURL(), Data::VERBATIM); + _dataModel.assign("_ioprocessors['http']", data); + } + } + + 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++) { + initializeData(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++) { + initializeData(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(); + +} + +/** + * Called with a single data element from the topmost datamodel element. + */ +void InterpreterDraft7::initializeData(const Arabica::DOM::Node<std::string>& data) { + if (!_dataModel) { + LOG(ERROR) << "Cannot initialize data when no datamodel is given!"; + return; + } + try { + if (!HAS_ATTR(data, "id")) { + LOG(ERROR) << "Data element has no id!"; + return; + } + + if (HAS_ATTR(data, "expr")) { + std::string value = ATTR(data, "expr"); + _dataModel.assign(ATTR(data, "id"), value); + } else if (HAS_ATTR(data, "src")) { + URL srcURL(ATTR(data, "src")); + if (!srcURL.isAbsolute()) + toAbsoluteURI(srcURL); + + std::stringstream ss; + if (_cachedURLs.find(srcURL.asString()) != _cachedURLs.end()) { + ss << _cachedURLs[srcURL.asString()]; + } else { + ss << srcURL; + _cachedURLs[srcURL.asString()] = srcURL; + } + _dataModel.assign(ATTR(data, "id"), ss.str()); + + } else if (data.hasChildNodes()) { + // search for the text node with the actual script + NodeList<std::string> dataChilds = data.getChildNodes(); + for (int i = 0; i < dataChilds.getLength(); i++) { + if (dataChilds.item(i).getNodeType() == Node_base::TEXT_NODE) { + Data value = Data(dataChilds.item(i).getNodeValue()); + _dataModel.assign(ATTR(data, "id"), value); + break; + } + } + } + + } catch (Event e) { + LOG(ERROR) << "Syntax error in data element:" << std::endl << e << std::endl; + } +} + +/** +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() { +} + +/** +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) { +} + +/** +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) { +} + +/** + 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) { +} + +/** +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) { +} + +/** + 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) { +} + +/** + 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) { +} + +/** + 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) { +} + + +}
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