Removal of discarded inventory offers moved to deferred (idle) tick. Nested gInventory.notifyObservers() don't work.

indra/newview/llappviewer.cpp

@@ -331,6 +331,40 @@ static std::string gLaunchFileOnQuit;
 // Used on Win32 for other apps to identify our window (eg, win_setup)
 const char* const VIEWER_WINDOW_CLASSNAME = "Second Life"; // Don't change
 
+//-- LLDeferredTaskList ------------------------------------------------------
+
+/**
+ * A list of deferred tasks.
+ *
+ * We sometimes need to defer execution of some code until the viewer gets idle,
+ * e.g. removing an inventory item from within notifyObservers() may not work out.
+ *
+ * Tasks added to this list will be executed in the next LLAppViewer::idle() iteration.
+ * All tasks are executed only once.
+ */
+class LLDeferredTaskList: public LLSingleton<LLDeferredTaskList>
+{
+	LOG_CLASS(LLDeferredTaskList);
+
+	friend class LLAppViewer;
+	typedef boost::signals2::signal<void()> signal_t;
+
+	void addTask(const signal_t::slot_type& cb)
+	{
+		mSignal.connect(cb);
+	}
+
+	void run()
+	{
+		if (!mSignal.empty())
+		{
+			mSignal();
+			mSignal.disconnect_all_slots();
+		}
+	}
+
+	signal_t mSignal;
+};
 //----------------------------------------------------------------------------
 // File scope definitons
 const char *VFS_DATA_FILE_BASE = "data.db2.x.";
@@ -3348,6 +3382,11 @@ bool LLAppViewer::initCache()
 	}
 }
 
+void LLAppViewer::addOnIdleCallback(const boost::function<void()>& cb)
+{
+	LLDeferredTaskList::instance().addTask(cb);
+}
+
 void LLAppViewer::purgeCache()
 {
 	LL_INFOS("AppCache") << "Purging Cache and Texture Cache..." << llendl;
@@ -3932,6 +3971,9 @@ void LLAppViewer::idle()
 			gAudiop->idle(max_audio_decode_time);
 		}
 	}
+
+	// Execute deferred tasks.
+	LLDeferredTaskList::instance().run();
 	
 	// Handle shutdown process, for example, 
 	// wait for floaters to close, send quit message,

indra/newview/llappviewer.h

@@ -158,6 +158,7 @@ public:
 	// *NOTE:Mani Fix this for login abstraction!!
 	void handleLoginComplete();
 
+	void addOnIdleCallback(const boost::function<void()>& cb); // add a callback to fire (once) when idle
 
 	void purgeCache(); // Clear the local cache. 
 protected:

indra/newview/llinventorymodel.cpp

@@ -3548,6 +3548,28 @@ void LLInventoryModel::processMoveInventoryItem(LLMessageSystem* msg, void**)
 	}
 }
 
+
+void LLInventoryModel::removeItem(const LLUUID& item_id)
+{
+	LLViewerInventoryItem* item = getItem(item_id);
+	const LLUUID new_parent = findCategoryUUIDForType(LLFolderType::FT_TRASH);
+	if(item && new_parent.notNull() && item->getParentUUID() != new_parent)
+	{
+		LLInventoryModel::update_list_t update;
+		LLInventoryModel::LLCategoryUpdate old_folder(item->getParentUUID(), -1);
+		update.push_back(old_folder);
+		LLInventoryModel::LLCategoryUpdate new_folder(new_parent, 1);
+		update.push_back(new_folder);
+		accountForUpdate(update);
+
+		LLPointer<LLViewerInventoryItem> new_item = new LLViewerInventoryItem(item);
+		new_item->setParent(new_parent);
+		new_item->updateParentOnServer(TRUE);
+		updateItem(new_item);
+		notifyObservers();
+	}
+}
+
 const LLUUID &LLInventoryModel::getRootFolderID() const
 {
 	return mRootFolderID;

indra/newview/llinventorymodel.h

@@ -343,6 +343,7 @@ public:
 	// consistent internal state. No cache accounting, observer
 	// notification, or server update is performed.
 	void deleteObject(const LLUUID& id);
+	void removeItem(const LLUUID& item_id);
 	
 	// Delete a particular inventory object by ID, and delete it from
 	// the server. Also updates linked items.

indra/newview/llviewermessage.cpp

@@ -865,37 +865,13 @@ public:
 	virtual void done()
 	{
 		LL_DEBUGS("Messaging") << "LLDiscardAgentOffer::done()" << LL_ENDL;
-		const LLUUID trash_id = gInventory.findCategoryUUIDForType(LLFolderType::FT_TRASH);
-		bool notify = false;
-		if(trash_id.notNull() && mObjectID.notNull())
-		{
-			LLInventoryModel::update_list_t update;
-			LLInventoryModel::LLCategoryUpdate old_folder(mFolderID, -1);
-			update.push_back(old_folder);
-			LLInventoryModel::LLCategoryUpdate new_folder(trash_id, 1);
-			update.push_back(new_folder);
-			gInventory.accountForUpdate(update);
-			gInventory.moveObject(mObjectID, trash_id);
-			LLInventoryObject* obj = gInventory.getObject(mObjectID);
-			if(obj)
-			{
-				// no need to restamp since this is already a freshly
-				// stamped item.
-				obj->updateParentOnServer(FALSE);
-				notify = true;
-			}
-		}
-		else
-		{
-			LL_WARNS("Messaging") << "DiscardAgentOffer unable to find: "
-					<< (trash_id.isNull() ? "trash " : "")
-					<< (mObjectID.isNull() ? "object" : "") << LL_ENDL;
-		}
+
+		// We're invoked from LLInventoryModel::notifyObservers().
+		// If we now try to remove the inventory item, it will cause a nested
+		// notifyObservers() call, which won't work.
+		// So defer moving the item to trash until viewer gets idle (in a moment).
+		LLAppViewer::instance()->addOnIdleCallback(boost::bind(&LLInventoryModel::removeItem, &gInventory, mObjectID));
 		gInventory.removeObserver(this);
-		if(notify)
-		{
-			gInventory.notifyObservers();
-		}
 		delete this;
 	}
 protected: