Add a sequence count to DataPacketFlying.

Set with adding to the flyingQueue.

NCPCompatProtocolLib/src/main/java/fr/neatmonster/nocheatplus/checks/net/protocollib/MovingFlying.java

@@ -96,6 +96,7 @@ public class MovingFlying extends BaseAdapter {
         // Always update last received time.
         final NetData data = dataFactory.getData(player);
         data.lastKeepAliveTime = time; // Update without much of a contract.
+        // TODO: Leniency options too (packet order inversion).
         if (!cc.flyingFrequencyActive) {
             return;
         }

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/net/NetData.java

@@ -82,6 +82,11 @@ public class NetData extends ACheckData {
     private final LinkedList<DataPacketFlying> flyingQueue = new LinkedList<DataPacketFlying>();
     /** Maximum amount of packets to store. */
     private final int flyingQueueMaxSize = 10;
+    /**
+     * The maximum of so far already returned sequence values, altered under
+     * lock.
+     */
+    private long maxSequence = 0;
 
     public NetData(final NetConfig config) {
         super(config);
@@ -100,7 +105,8 @@ public class NetData extends ACheckData {
     }
 
     /**
-     * Add a packet to the queue (under lock).
+     * Add a packet to the queue (under lock). The sequence number of the packet
+     * will be set here, according to a count maintained per-data.
      * 
      * @param packetData
      * @return If a packet has been removed due to exceeding maximum size.
@@ -108,6 +114,7 @@ public class NetData extends ACheckData {
     public boolean addFlyingQueue(final DataPacketFlying packetData) {
         boolean res = false;
         lock.lock();
+        packetData.setSequence(++maxSequence);
         flyingQueue.addFirst(packetData);
         if (flyingQueue.size() > flyingQueueMaxSize) {
             flyingQueue.removeLast();

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/net/model/DataPacketFlying.java

@@ -25,6 +25,7 @@ public class DataPacketFlying extends DataLocation {
     public final boolean hasPos;
     public final boolean hasLook;
     public final long time;
+    private long sequence = 0;
 
     public DataPacketFlying(boolean onGround, long time) {
         super(0, 0, 0, 0, 0);
@@ -117,4 +118,18 @@ public class DataPacketFlying extends DataLocation {
         return builder.toString();
     }
 
+    /**
+     * Get the sequence number. This may or may not be set, depending on
+     * context.
+     * 
+     * @return
+     */
+    public long getSequence() {
+        return sequence;
+    }
+
+    public void setSequence(long sequence) {
+        this.sequence = sequence;
+    }
+
 }