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#include "uscxml/Interpreter.h"
#include "uscxml/interpreter/InterpreterMonitor.h"
#include "uscxml/interpreter/InterpreterImpl.h"
#include "uscxml/interpreter/BasicEventQueue.h"
#include "uscxml/interpreter/BasicDelayedEventQueue.h"
#include <event2/util.h> // for evutil_socket_t
#include <chrono>
#include <mutex>
using namespace uscxml;
// from issue 96:
// https://github.com/tklab-tud/uscxml/issues/96
static const char *customDelayedEQ =
"<scxml initial=\"StateShape1\" name=\"ScxmlShape1\" version=\"1.0\" xmlns=\"http://www.w3.org/2005/07/scxml\">"
" <state id=\"StateShape1\">"
" <invoke autoforward=\"true\" type=\"scxml\">"
" <content>"
" <scxml initial=\"StateShape1\" name=\"Include\" version=\"1.0\" xmlns=\"http://www.w3.org/2005/07/scxml\">"
" <state id=\"StateShape1\">"
" <transition event=\"error.*\" target=\"FinalShape1\"/>"
" <state id=\"Step1\">"
" <onentry>"
" <send delay=\"1s\" event=\"Timer2\"/>"
" <log expr=\"'Hello from step1'\"/>"
" </onentry>"
" <transition event=\"Timer2\" target=\"Step2\"/>"
" </state>"
" <state id=\"Step2\">"
" <onentry>"
" <send delay=\"1s\" event=\"Timer2\"/>"
" <log expr=\"'Hello from step2'\"/>"
" </onentry>"
" <transition event=\"Timer2\" target=\"Step1\"/>"
" </state>"
" </state>"
" <final id=\"FinalShape1\"/>"
" </scxml>"
" </content>"
" </invoke>"
" </state>"
" <final id=\"FinalShape1\"/>"
"</scxml>";
class PausableDelayedEventQueue;
std::shared_ptr<PausableDelayedEventQueue> nestedDelayQueue;
/**
* A DelayedEventQueue that implements pause/resume
*/
class PausableDelayedEventQueue : public BasicDelayedEventQueue {
public:
PausableDelayedEventQueue(DelayedEventQueueCallbacks* callbacks) : BasicDelayedEventQueue(callbacks) {}
std::shared_ptr<DelayedEventQueueImpl> create(DelayedEventQueueCallbacks* callbacks) {
// remember as nestedDelayQueue in global scope
nestedDelayQueue = std::shared_ptr<PausableDelayedEventQueue>(new PausableDelayedEventQueue(callbacks));
return nestedDelayQueue;
}
void pause() {
if(_pausedAt.tv_sec != 0 || _pausedAt.tv_usec != 0) {
return; // we are already paused!
}
evutil_gettimeofday(&_pausedAt, NULL); // remember when we paused
{
// Verbatim copy of stop() without cancelAllDelayed()
if (_isStarted) {
_isStarted = false;
event_base_loopbreak(_eventLoop);
}
if (_thread) {
_thread->join();
delete _thread;
_thread = NULL;
}
}
std::lock_guard<std::recursive_mutex> lock(_mutex);
// remove all events from libevent without deleting them
for(auto callbackData : _callbackData) {
Event data = callbackData.second.userData;
event_del(callbackData.second.event);
}
}
void resume() {
if (_pausedAt.tv_sec != 0 || _pausedAt.tv_usec != 0) {
struct timeval now;
struct timeval pausedFor;
evutil_gettimeofday(&now, NULL);
evutil_timersub(&now, &_pausedAt, &pausedFor);
_pausedAt = {0,0};
for(auto& callbackData : _callbackData) {
// add the time we were paused to all due times
evutil_timeradd(&callbackData.second.due, &pausedFor, &callbackData.second.due);
struct timeval remain;
evutil_timersub(&callbackData.second.due, &now, &remain);
#if 0
std::cout << "Now : " << now.tv_sec << "." << now.tv_usec << std::endl;
std::cout << "Paused : " << pausedFor.tv_sec << "." << pausedFor.tv_usec << std::endl;
std::cout << "Remaining: " << remain.tv_sec << "." << remain.tv_usec << std::endl;
#endif
assert(remain.tv_usec >= 0 && remain.tv_sec >= 0);
// reenqueue with libevent
event_add(callbackData.second.event, &remain);
}
}
start();
}
protected:
timeval _pausedAt = {0,0};
};
bool testPausableEventQueue() {
Interpreter interpreter = Interpreter::fromXML(customDelayedEQ, "");
PausableDelayedEventQueue* queue = new PausableDelayedEventQueue(interpreter.getImpl().get());
ActionLanguage lang;
lang.delayedQueue = DelayedEventQueue(std::shared_ptr<DelayedEventQueueImpl>(queue));
interpreter.setActionLanguage(lang);
StateTransitionMonitor mon;
mon.copyToInvokers(true);
interpreter.addMonitor(&mon);
size_t iterations = 10;
InterpreterState state = InterpreterState::USCXML_UNDEF;
while (state != USCXML_FINISHED) {
state = interpreter.step();
if (nestedDelayQueue) {
/*
* As soon as we have the nested event queue instantiated, we pause and resume it
* We pause for 500ms, and run for 500ms. This will effectively double the time required
* for delayed events.
* This would usually done in another thread ..
*/
std::cout << "<- pausing" << std::endl;
nestedDelayQueue->pause();
std::this_thread::sleep_for(std::chrono::milliseconds(500));
std::cout << "-> continuing" << std::endl;
nestedDelayQueue->resume();
std::this_thread::sleep_for(std::chrono::milliseconds(500));
if (iterations-- == 0)
return true;
}
}
return true;
}
int main(int argc, char** argv) {
testPausableEventQueue();
}
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