From 51fed0676eb5abf02268eaf2a33b71f467fcbe2d Mon Sep 17 00:00:00 2001
From: Andrzej Kapolka <andrzej@threerings.net>
Date: Wed, 14 Feb 2007 02:30:37 +0000
Subject: [PATCH] Use the number of subscribers to determine how many responses
 to expect. Take the lock immediately if there are no subscribers.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@4576 542714f4-19e9-0310-aa3c-eee0fc999fb1
---
 .../presents/peer/data/NodeObject.java        | 34 ++++++++++++-------
 .../presents/peer/server/PeerManager.java     | 16 +++++++--
 2 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/src/java/com/threerings/presents/peer/data/NodeObject.java b/src/java/com/threerings/presents/peer/data/NodeObject.java
index a597b352d..faeeaac29 100644
--- a/src/java/com/threerings/presents/peer/data/NodeObject.java
+++ b/src/java/com/threerings/presents/peer/data/NodeObject.java
@@ -60,20 +60,20 @@ public class NodeObject extends DObject
     {
         /** The resource type.  Only resources of the same type will have their ids compared. */
         public String type;
-        
+
         /** The resource identifier, which can be <code>null</code> for singleton resources. */
         public Comparable id;
-        
+
         public Lock ()
         {
         }
-        
+
         public Lock (String type, Comparable id)
         {
             this.type = type;
             this.id = id;
         }
-        
+
         // documentation inherited from interface Comparable
         public int compareTo (Object other)
         {
@@ -85,19 +85,19 @@ public class NodeObject extends DObject
             @SuppressWarnings("unchecked") int v2 = id.compareTo(olock.id);
             return v2;
         }
-        
+
         // documentation inherited from interface DSet.Entry
         public Comparable getKey ()
         {
             return this;
         }
-        
+
         @Override // documentation inherited
         public int hashCode ()
         {
             return type.hashCode() + (id == null ? 0 : id.hashCode());
         }
-        
+
         @Override // documentation inherited
         public boolean equals (Object other)
         {
@@ -105,7 +105,7 @@ public class NodeObject extends DObject
             return type.equals(olock.type) && ObjectUtil.equals(id, olock.id);
         }
     }
-    
+
     /** Used for informing peers of changes to persistent data. */
     public static class CacheData extends SimpleStreamableObject
     {
@@ -115,8 +115,8 @@ public class NodeObject extends DObject
         /** The stale data in the cache. */
         public Streamable data;
 
-        public CacheData () 
-        { 
+        public CacheData ()
+        {
         }
 
         public CacheData (String cache, Streamable data)
@@ -128,7 +128,7 @@ public class NodeObject extends DObject
 
     /** The service used to make requests of the node. */
     public PeerMarshaller peerService;
-    
+
     /** Contains information on all clients connected to this node. */
     public DSet<ClientInfo> clients = new DSet<ClientInfo>();
 
@@ -137,13 +137,21 @@ public class NodeObject extends DObject
 
     /** Used to broadcast a node's desire to acquire a lock. */
     public Lock acquiringLock;
-    
+
     /** Used to broadcast a node's desire to release a lock. */
     public Lock releasingLock;
-    
+
     /** A field we use to broadcast changes to possible cached data. */
     public CacheData cacheData;
 
+    /**
+     * Returns the number of subscribers to this node.
+     */
+    public int getSubscriberCount ()
+    {
+        return _scount;
+    }
+
     // AUTO-GENERATED: METHODS START
     /**
      * Requests that the <code>peerService</code> field be set to the
diff --git a/src/java/com/threerings/presents/peer/server/PeerManager.java b/src/java/com/threerings/presents/peer/server/PeerManager.java
index 3dbf42db0..ba66be2d2 100644
--- a/src/java/com/threerings/presents/peer/server/PeerManager.java
+++ b/src/java/com/threerings/presents/peer/server/PeerManager.java
@@ -296,7 +296,12 @@ public class PeerManager
         queryLock(lock, new ResultListener<String>() {
             public void requestCompleted (String result) {
                 if (result == null) {
-                    _locks.put(lock, new LockHandler(lock, true, listener));
+                    if (_nodeobj.getSubscriberCount() == 0) {
+                        _nodeobj.addToLocks(lock);
+                        listener.requestCompleted(_nodeName);
+                    } else {
+                        _locks.put(lock, new LockHandler(lock, true, listener));
+                    }
                 } else {
                     listener.requestCompleted(result);
                 }
@@ -318,7 +323,12 @@ public class PeerManager
         queryLock(lock, new ResultListener<String>() {
             public void requestCompleted (String result) {
                 if (_nodeName.equals(result)) {
-                    _locks.put(lock, new LockHandler(lock, false, listener));
+                    if (_nodeobj.getSubscriberCount() == 0) {
+                        _nodeobj.removeFromLocks(lock);
+                        listener.requestCompleted(null);
+                    } else {
+                        _locks.put(lock, new LockHandler(lock, false, listener));
+                    }
                 } else {
                     if (result != null) {
                         log.warning("Tried to release lock held by another peer [lock=" +
@@ -796,7 +806,7 @@ public class PeerManager
             }
 
             // find out exactly how many responses we need
-            _remaining = _peers.size();
+            _remaining = _nodeobj.getSubscriberCount();
 
             // schedule a timeout to act if something goes wrong
             (_timeout = new Interval(PresentsServer.omgr) {