Merge pull request #59 from ebertin/fix/progress_race

Guard progress observers with a mutex

Author: ayllon

SEMain/SEMain/ProgressMediator.h

@@ -12,6 +12,7 @@
 #include "SEFramework/Pipeline/Segmentation.h"
 #include "SEUtils/Observable.h"
 #include <atomic>
+#include <mutex>
 
 namespace SExtractor {
 
@@ -75,6 +76,10 @@ class ProgressMediator: public ProgressObservable, public DoneObservable {
   std::shared_ptr<source_observer_t> m_detection_listener;
   std::shared_ptr<group_observer_t> m_deblending_listener, m_measurement_listener;
 
+  // Mediator serializes the notifications, so the observers do not need to worry about
+  // being called from multiple threads
+  std::mutex m_mutex;
+
   // This is a set of internal classes that implement the Observer pattern for different stages.
   class ProgressCounter;
   class SourceCounter;

SEMain/src/lib/ProgressMediator.cpp

@@ -82,6 +82,7 @@ std::shared_ptr<ProgressMediator::group_observer_t>& ProgressMediator::getMeasur
 }
 
 void ProgressMediator::update(void) {
+  std::lock_guard<std::mutex> guard(m_mutex);
   this->ProgressObservable::notifyObservers(std::map<std::string, std::pair<int, int>>{
     {"Detected",     {m_detected,                       -1}},
     {"Deblended",    {m_deblended,                      -1}},
@@ -91,6 +92,7 @@ void ProgressMediator::update(void) {
 }
 
 void ProgressMediator::done() {
+  std::lock_guard<std::mutex> guard(m_mutex);
   this->DoneObservable::notifyObservers(true);
 }