From c05105e2f9d556358d529c5798e03edb10f22fd7 Mon Sep 17 00:00:00 2001
From: Atlante45 <clement.brisset@gmail.com>
Date: Tue, 14 Jul 2015 15:29:49 -0700
Subject: [PATCH] Added takeFront method to PacketList

---
 libraries/networking/src/LimitedNodeList.cpp |  6 ++----
 libraries/networking/src/udt/PacketList.h    | 13 +++++++++++++
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/libraries/networking/src/LimitedNodeList.cpp b/libraries/networking/src/LimitedNodeList.cpp
index d54fbd093b..005499cc53 100644
--- a/libraries/networking/src/LimitedNodeList.cpp
+++ b/libraries/networking/src/LimitedNodeList.cpp
@@ -288,10 +288,8 @@ qint64 LimitedNodeList::sendPacketList(NLPacketList& packetList, const Node& des
 
 qint64 LimitedNodeList::sendPacketList(NLPacketList& packetList, const HifiSockAddr& sockAddr) {
     qint64 bytesSent{ 0 };
-    auto& packets = packetList._packets;
-    while (!packets.empty()) {
-        bytesSent += sendPacket(std::move(packets.front()), sockAddr);
-        packets.pop_front();
+    while (!packetList._packets.empty()) {
+        bytesSent += sendPacket(std::move(packetList.takeFront<NLPacket>()), sockAddr);
     }
     
     return bytesSent;
diff --git a/libraries/networking/src/udt/PacketList.h b/libraries/networking/src/udt/PacketList.h
index cbd2870ed8..173e8c75fb 100644
--- a/libraries/networking/src/udt/PacketList.h
+++ b/libraries/networking/src/udt/PacketList.h
@@ -47,6 +47,10 @@ private:
     PacketList(const PacketList& other) = delete;
     PacketList& operator=(const PacketList& other) = delete;
     
+    // Takes the first packet of the list and returns it.
+    template<typename T> std::unique_ptr<T> takeFront();
+    
+    // Creates a new packet, can be overriden to change return underlying type
     virtual std::unique_ptr<Packet> createPacket();
     std::unique_ptr<Packet> createPacketWithExtendedHeader();
     
@@ -62,6 +66,7 @@ private:
 };
 
 template <typename T> qint64 PacketList::readPrimitive(T* data) {
+    static_assert(!std::is_pointer<T>::value, "T must not be a pointer");
     return QIODevice::read(reinterpret_cast<char*>(data), sizeof(T));
 }
 
@@ -70,4 +75,12 @@ template <typename T> qint64 PacketList::writePrimitive(const T& data) {
     return QIODevice::write(reinterpret_cast<const char*>(&data), sizeof(T));
 }
 
+template<typename T> std::unique_ptr<T> PacketList::takeFront() {
+    static_assert(std::is_base_of<Packet, T>::value, "T must derive from Packet.");
+    
+    auto packet = std::move(_packets.front());
+    _packets.pop_front();
+    return std::move(std::unique_ptr<T>(dynamic_cast<T*>(packet.release())));
+}
+
 #endif // hifi_PacketList_h
\ No newline at end of file