From fb7cb7ff5368b8c0077055835c372204c8070207 Mon Sep 17 00:00:00 2001
From: Stephen Birarda <commit@birarda.com>
Date: Tue, 14 Jul 2015 15:49:54 -0700
Subject: [PATCH] add the option for PacketReceiver to drop packets

---
 assignment-client/src/AssignmentClient.cpp      | 3 +++
 interface/src/Application.cpp                   | 9 ++++-----
 libraries/networking/src/PacketReceiver.cpp     | 5 +++++
 libraries/networking/src/PacketReceiver.h       | 4 +++-
 libraries/networking/src/ThreadedAssignment.cpp | 7 ++++++-
 5 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/assignment-client/src/AssignmentClient.cpp b/assignment-client/src/AssignmentClient.cpp
index c81a521552..bc2b18cb53 100644
--- a/assignment-client/src/AssignmentClient.cpp
+++ b/assignment-client/src/AssignmentClient.cpp
@@ -330,6 +330,9 @@ void AssignmentClient::assignmentCompleted() {
 
     auto nodeList = DependencyManager::get<NodeList>();
 
+    // tell the packet receiver to stop dropping packets
+    nodeList->getPacketReceiver().setShouldDropPackets(false);
+
     // reset our NodeList by switching back to unassigned and clearing the list
     nodeList->setOwnerType(NodeType::Unassigned);
     nodeList->reset();
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 57f2b7c523..824de916d5 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -663,12 +663,11 @@ void Application::aboutToQuit() {
 
 void Application::cleanupBeforeQuit() {
 
-    // stop handling packets we've asked to handle
-    DependencyManager::get<LimitedNodeList>()->getPacketReceiver().unregisterListener(this);
-
     _entities.clear(); // this will allow entity scripts to properly shutdown
-
-    //_datagramProcessor->shutdown(); // tell the datagram processor we're shutting down, so it can short circuit
+    
+    // tell the packet receiver we're shutting down, so it can drop packets
+    DependencyManager::get<NodeList>()->getPacketReceiver().setShouldDropPackets(true);
+    
     _entities.shutdown(); // tell the entities system we're shutting down, so it will stop running scripts
     ScriptEngine::stopAllScripts(this); // stop all currently running global scripts
 
diff --git a/libraries/networking/src/PacketReceiver.cpp b/libraries/networking/src/PacketReceiver.cpp
index 1f163cdaf3..4c3f268d06 100644
--- a/libraries/networking/src/PacketReceiver.cpp
+++ b/libraries/networking/src/PacketReceiver.cpp
@@ -180,6 +180,11 @@ void PacketReceiver::processDatagrams() {
         // setup a buffer to read the packet into
         int packetSizeWithHeader = nodeList->getNodeSocket().pendingDatagramSize();
         std::unique_ptr<char> buffer = std::unique_ptr<char>(new char[packetSizeWithHeader]);
+
+        // if we're supposed to drop this packet then break out here
+        if (_shouldDropPackets) {
+            break;
+        }
         
         // setup a HifiSockAddr to read into
         HifiSockAddr senderSockAddr;
diff --git a/libraries/networking/src/PacketReceiver.h b/libraries/networking/src/PacketReceiver.h
index bf5889af1e..448ca07876 100644
--- a/libraries/networking/src/PacketReceiver.h
+++ b/libraries/networking/src/PacketReceiver.h
@@ -34,6 +34,8 @@ public:
     
     int getInPacketCount() const { return _inPacketCount; }
     int getInByteCount() const { return _inByteCount; }
+
+    void setShouldDropPackets(bool shouldDropPackets) { _shouldDropPackets = shouldDropPackets; }
     
     void resetCounters() { _inPacketCount = 0; _inByteCount = 0; }
 
@@ -61,7 +63,7 @@ private:
     QHash<PacketType::Value, ObjectMethodPair> _packetListenerMap;
     int _inPacketCount = 0;
     int _inByteCount = 0;
-    bool _isShuttingDown = false;
+    bool _shouldDropPackets = false;
 };
 
 #endif // hifi_PacketReceiver_h
diff --git a/libraries/networking/src/ThreadedAssignment.cpp b/libraries/networking/src/ThreadedAssignment.cpp
index 44d1aaf280..1c425806c9 100644
--- a/libraries/networking/src/ThreadedAssignment.cpp
+++ b/libraries/networking/src/ThreadedAssignment.cpp
@@ -34,8 +34,13 @@ void ThreadedAssignment::setFinished(bool isFinished) {
 
             qDebug() << "ThreadedAssignment::setFinished(true) called - finishing up.";
 
+            auto& packetReceiver = DependencyManager::get<NodeList>()->getPacketReceiver();
+
             // we should de-register immediately for any of our packets
-            DependencyManager::get<NodeList>()->getPacketReceiver().unregisterListener(this);
+            packetReceiver.unregisterListener(this);
+
+            // we should also tell the packet receiver to drop packets while we're cleaning up
+            packetReceiver.setShouldDropPackets(true);
 
             if (_domainServerTimer) {
                 _domainServerTimer->stop();