Selection: handle exception in observer callback

Selection callback are sometimes called while traversing Coin node tree.
If any unhandled exception is thrown while traversing the tree, FC 3D
rendering will become unstable and non-usable thereafter.

src/Base/Observer.h

@@ -32,7 +32,9 @@
 #include <set>
 #include <cstring>
 #include <cstdio>
-
+#include <exception>
+#include "Exception.h"
+#include "Console.h"
 
 namespace Base
 {
@@ -172,7 +174,19 @@ public:
   void Notify(_MessageType rcReason)
   {
     for(typename std::set<Observer<_MessageType> * >::iterator Iter=_ObserverSet.begin();Iter!=_ObserverSet.end();++Iter)
-      (*Iter)->OnChange(*this,rcReason);   // send OnChange-signal
+    {
+      try {
+        (*Iter)->OnChange(*this,rcReason);   // send OnChange-signal
+      } catch (Base::Exception &e) {
+        Base::Console().Error("Unhandled Base::Exception caught when notifying observer.\n"
+                              "The error message is: %s\n", e.what());
+      } catch (std::exception &e) {
+        Base::Console().Error("Unhandled std::exception caught when notifying observer\n"
+                              "The error message is: %s\n", e.what());
+      } catch (...) {
+        Base::Console().Error("Unhandled unknown exception caught in when notifying observer.\n");
+      }
+    }
   }
 
   /** Get an Observer by name

src/Gui/Selection.cpp

@@ -49,7 +49,7 @@
 #include <Gui/SelectionObjectPy.h>
 #include "MainWindow.h"
 
-
+FC_LOG_LEVEL_INIT("Selection",false,true,true)
 
 using namespace Gui;
 using namespace std;
@@ -83,7 +83,20 @@ void SelectionObserver::attachSelection()
 {
     if (!connectSelection.connected()) {
         connectSelection = Selection().signalSelectionChanged.connect(boost::bind
-            (&SelectionObserver::onSelectionChanged, this, _1));
+            (&SelectionObserver::_onSelectionChanged, this, _1));
+    }
+}
+
+void SelectionObserver::_onSelectionChanged(const SelectionChanges& msg) {
+    try { 
+        onSelectionChanged(msg);
+    } catch (Base::Exception &e) {
+        e.ReportException();
+        FC_ERR("Unhandled Base::Exception caught in selection observer: ");
+    } catch (std::exception &e) {
+        FC_ERR("Unhandled std::exception caught in selection observer: " << e.what());
+    } catch (...) {
+        FC_ERR("Unhandled unknown exception caught in selection observer");
     }
 }
 

src/Gui/Selection.h

@@ -141,6 +141,7 @@ public:
 
 private:
     virtual void onSelectionChanged(const SelectionChanges& msg) = 0;
+    void _onSelectionChanged(const SelectionChanges& msg);
 
 private:
     typedef boost::signals::connection Connection;