* I2PSnark:

- Fix (again) partial piece avoidance for seeds
   - Fix several partial piece (temp file) leaks,
     some uncovered by previous rarest-first fixes, some in end game
   - Don't lose all DHT peers if we stop quickly (backport from update branch)
   - Explore a kbucket if it's less than 3/4 full (backport from update branch)

apps/i2psnark/java/src/net/i2p/kademlia/KBucketSet.java

@@ -518,6 +518,7 @@ public class KBucketSet<T extends SimpleDataStructure> {
     
     /**
      *  For every bucket that hasn't been updated in this long,
+     *  or isn't close to full,
      *  generate a random key that would be a member of that bucket.
      *  The returned keys may be searched for to "refresh" the buckets.
      *  @return non-null, closest first
@@ -528,7 +529,7 @@ public class KBucketSet<T extends SimpleDataStructure> {
         getReadLock();
         try {
             for (KBucket b : _buckets) {
-                if (b.getLastChanged() < old)
+                if (b.getLastChanged() < old || b.getKeyCount() < BUCKET_SIZE * 3 / 4)
                     rv.add(generateRandomKey(b));
             }
         } finally { releaseReadLock(); }

apps/i2psnark/java/src/org/klomp/snark/PeerCoordinator.java

@@ -741,7 +741,19 @@ class PeerCoordinator implements PeerListener
                 break;
             if (havePieces.get(p.getId()) && !p.isRequested())
               {
-                piece = p;
+                // never ever choose one that's in partialPieces, or we
+                // will create a second one and leak
+                boolean hasPartial = false;
+                for (PartialPiece pp : partialPieces) {
+                    if (pp.getPiece() == p.getId()) {
+                        if (_log.shouldLog(Log.INFO))
+                            _log.info("wantPiece() skipping partial for " + peer + ": piece = " + pp);
+                        hasPartial = true;
+                        break;
+                    }
+                }
+                if (!hasPartial)
+                    piece = p;
               }
             else if (p.isRequested()) 
             {
@@ -943,11 +955,14 @@ class PeerCoordinator implements PeerListener
    */
   public boolean gotPiece(Peer peer, PartialPiece pp)
   {
-    if (metainfo == null || storage == null)
+    if (metainfo == null || storage == null) {
+        pp.release();
         return true;
+    }
     int piece = pp.getPiece();
     if (halted) {
       _log.info("Got while-halted piece " + piece + "/" + metainfo.getPieces() +" from " + peer + " for " + metainfo.getName());
+      pp.release();
       return true; // We don't actually care anymore.
     }
     
@@ -962,8 +977,10 @@ class PeerCoordinator implements PeerListener
             // Assume we got a good piece, we don't really care anymore.
             // Well, this could be caused by a change in priorities, so
             // only return true if we already have it, otherwise might as well keep it.
-            if (storage.getBitField().get(piece))
+            if (storage.getBitField().get(piece)) {
+                pp.release();
                 return true;
+            }
           }
         
         try
@@ -1277,6 +1294,7 @@ class PeerCoordinator implements PeerListener
               PartialPiece pp = iter.next();
               if (pp.getPiece() == piece) {
                   iter.remove();
+                  pp.release();
                   // there should be only one but keep going to be sure
               }
           }

apps/i2psnark/java/src/org/klomp/snark/PeerState.java

@@ -592,6 +592,7 @@ class PeerState implements DataLoader
                 // Send cancel even when we are choked to make sure that it is
                 // really never ever send.
                 out.sendCancel(req);
+                req.getPartialPiece().release();
               }
           }
   }
@@ -741,6 +742,10 @@ class PeerState implements DataLoader
                   out.sendRequest(r);
                 lastRequest = r;
                 return true;
+            } else {
+                if (_log.shouldLog(Log.WARN))
+                    _log.warn("Got dup from coord: " + pp);
+                pp.release();
             }
         }
 

apps/i2psnark/java/src/org/klomp/snark/dht/KRPC.java

@@ -572,7 +572,9 @@ public class KRPC implements I2PSessionMuxedListener, DHT {
         _session.removeListener(I2PSession.PROTO_DATAGRAM_RAW, _rPort);
         // clear the DHT and tracker
         _tracker.stop();
-        PersistDHT.saveDHT(_knownNodes, _dhtFile);
+        // don't lose all our peers if we didn't have time to check them
+        boolean saveAll = _context.clock().now() - _started < 20*60*1000;
+        PersistDHT.saveDHT(_knownNodes, saveAll, _dhtFile);
         _knownNodes.stop();
         for (Iterator<ReplyWaiter> iter = _sentQueries.values().iterator(); iter.hasNext(); ) {
             ReplyWaiter waiter = iter.next();

apps/i2psnark/java/src/org/klomp/snark/dht/PersistDHT.java

@@ -56,12 +56,15 @@ abstract class PersistDHT {
             log.info("Loaded " + count + " nodes from " + file);
     }
 
-    public static synchronized void saveDHT(DHTNodes nodes, File file) {
+    /**
+     *  @param saveAll if true, don't check last seen time
+     */
+    public static synchronized void saveDHT(DHTNodes nodes, boolean saveAll, File file) {
         if (nodes.size() <= 0)
             return;
         Log log = I2PAppContext.getGlobalContext().logManager().getLog(PersistDHT.class);
         int count = 0;
-        long maxAge = I2PAppContext.getGlobalContext().clock().now() - MAX_AGE;
+        long maxAge = saveAll ? 0 : I2PAppContext.getGlobalContext().clock().now() - MAX_AGE;
         PrintWriter out = null;
         try {
             out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(new SecureFileOutputStream(file), "ISO-8859-1")));