From 8dc262b12992c7cd8d4bee0fa4114ee3fb6dcd87 Mon Sep 17 00:00:00 2001
From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Sun, 20 Sep 2015 18:09:29 +0200
Subject: [PATCH] keep track of packet loss

---
 src/net/ConnectionHandler.hpp | 20 +++++++++++++++++---
 src/net/net.cpp               | 33 +++++++++++++++++++++++++++++++--
 2 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/src/net/ConnectionHandler.hpp b/src/net/ConnectionHandler.hpp
index 6e18da2..942826b 100644
--- a/src/net/ConnectionHandler.hpp
+++ b/src/net/ConnectionHandler.hpp
@@ -11,16 +11,25 @@ namespace blank {
 class ConnectionHandler {
 
 public:
+	ConnectionHandler();
+
+	float PacketLoss() const noexcept { return packet_loss; }
+
+	void PacketLost(std::uint16_t);
+	void PacketReceived(std::uint16_t);
+
 	void Handle(const UDPpacket &);
 
+	virtual void OnTimeout() { }
+
+private:
+	void UpdatePacketLoss() noexcept;
+
 	// called as soon as the remote end ack'd given packet
 	virtual void OnPacketReceived(std::uint16_t) { }
 	// called if the remote end probably didn't get given packet
 	virtual void OnPacketLost(std::uint16_t) { }
 
-	virtual void OnTimeout() { }
-
-private:
 	virtual void On(const Packet::Ping &) { }
 	virtual void On(const Packet::Login &) { }
 	virtual void On(const Packet::Join &) { }
@@ -33,6 +42,11 @@ private:
 	virtual void On(const Packet::ChunkBegin &) { }
 	virtual void On(const Packet::ChunkData &) { }
 
+private:
+	unsigned int packets_lost;
+	unsigned int packets_received;
+	float packet_loss;
+
 };
 
 }
diff --git a/src/net/net.cpp b/src/net/net.cpp
index 81de3e4..0f8aa21 100644
--- a/src/net/net.cpp
+++ b/src/net/net.cpp
@@ -118,14 +118,14 @@ void Connection::Received(const UDPpacket &udp_pack) {
 		if (diff > 0) {
 			for (int i = 0; i < diff; ++i) {
 				if (i > 32 || (i < 32 && (ctrl_in.hist & (1 << (31 - i))) == 0)) {
-					Handler().OnPacketLost(ctrl_in.ack - 32 + i);
+					Handler().PacketLost(ctrl_in.ack - 32 + i);
 				}
 			}
 		}
 		// check for newly ack'd packets
 		for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); --s) {
 			if (ctrl_new.Acks(s) && !ctrl_in.Acks(s)) {
-				Handler().OnPacketReceived(s);
+				Handler().PacketReceived(s);
 			}
 		}
 		ctrl_in = ctrl_new;
@@ -145,6 +145,35 @@ uint16_t Connection::SendPing(UDPpacket &udp_pack, UDPsocket sock) {
 }
 
 
+ConnectionHandler::ConnectionHandler()
+: packets_lost(0)
+, packets_received(0)
+, packet_loss(0.0f) {
+
+}
+
+void ConnectionHandler::PacketLost(uint16_t seq) {
+	OnPacketLost(seq);
+	++packets_lost;
+	UpdatePacketLoss();
+}
+
+void ConnectionHandler::PacketReceived(uint16_t seq) {
+	OnPacketReceived(seq);
+	++packets_received;
+	UpdatePacketLoss();
+}
+
+void ConnectionHandler::UpdatePacketLoss() noexcept {
+	unsigned int packets_total = packets_lost + packets_received;
+	if (packets_total >= 256) {
+		packet_loss = float(packets_lost) / float(packets_total);
+		packets_lost = 0;
+		packets_received = 0;
+	}
+}
+
+
 ostream &operator <<(ostream &out, const IPaddress &addr) {
 	const unsigned char *host = reinterpret_cast<const unsigned char *>(&addr.host);
 	out << int(host[0])
-- 
2.39.2