Refactored Matthew fix for vardiff.

Fixed .size() bug that was causing crash

Merge branch 'master' of https://github.com/zone117x/node-stratum

Conflicts:
	lib/jobManager.js

lib/jobManager.js

@@ -1,4 +1,5 @@
 var events = require('events');
+var crypto = require('crypto');
 
 var bignum = require('bignum');
 
@@ -14,18 +15,17 @@ var blockTemplate = require('./blockTemplate.js');
 
 
 //Unique extranonce per subscriber
-var ExtraNonceCounter = function(){
-    var instanceId = 31;
+var ExtraNonceCounter = function(configInstanceId){
+
+    var instanceId = configInstanceId || crypto.randomBytes(4).readUInt32LE(0);
     var counter = instanceId << 27;
-    var size = util.packUInt32BE(Math.abs(counter)).length;
 
     this.next = function(){
         var extraNonce = util.packUInt32BE(Math.abs(counter++));
         return extraNonce.toString('hex');
     };
-    this.size = function(){
-        return size;
-    };
+
+    this.size = 4; //bytes
 };
 
 //Unique job per new block template
@@ -126,9 +126,9 @@ var JobManager = module.exports = function JobManager(options){
     
     //public members
 
-    this.extraNonceCounter     = new ExtraNonceCounter();
+    this.extraNonceCounter     = new ExtraNonceCounter(options.instanceId);
     this.extraNoncePlaceholder = new Buffer('f000000ff111111f', 'hex');
-    this.extraNonce2Size       = this.extraNoncePlaceholder.length - this.extraNonceCounter.size();
+    this.extraNonce2Size       = this.extraNoncePlaceholder.length - this.extraNonceCounter.size;
 
     this.currentJob;
 

lib/pool.js

@@ -50,31 +50,10 @@ var pool = module.exports = function pool(options, authorizeFn){
             emitLog('varDiff', 'Difficulty requested for vardiff');
             if (_this.stratumServer)
                 RequestDifficulty(function(){});
-        }).on('newDifficulty', function(client, newDiff){
-            client.sendDifficulty(newDiff);
-
-            /*
-            Disabled this line of code because it will force the miner
-            to restart and submit duplicate shares. Stratum-python sends out a
-            mining.notify but rolls the jobID and sets "clean jobs" to false.
-            Meaning that the worker will only start on the new work once it
-            exhausts its current nonce range. But if the miner were to start the
-            new job, the shares would be invalidated since stratum-python doesn't
-            insert the new jobID that the share-limiter generated into the jobs
-            array. Even worse, since the new work is only sent with a new jobID
-            but with the same extranonce and other job parameters as the last job,
-            the shares will be duplicate. Perhaps this bug has gone unnoticed
-            because of how likely it is for a miner to exhaust the nonce range
-            before new work is sent.
-
-            Here is where stratum-python is bugged:
-            https://github.com/Crypto-Expert/stratum-mining/blob/master/mining/basic_share_limiter.py#L171-L178
-
-            So lets only send a new difficulty, and the worker will use it when
-            it receives a new job from when the block template updates.
-            */
-            //client.sendMiningJob(_this.jobManager.currentJob.getJobParams());
-
+        }).on('newDifficulty', function(client, newDiff) {
+            // We request to set the newDiff @ the next difficulty retarget 
+            // (which should happen when a new job comes in - AKA BLOCK)
+            client.enqueueNextDifficulty(newDiff);
         });
         emitLog("system", "VarDiff enabled and setup");
     }

lib/stratum.js

@@ -24,7 +24,7 @@ var SubscriptionCounter = function(){
  *  - submit(data(name, jobID, extraNonce2, ntime, nonce))
 **/
 var StratumClient = function(options){
-
+    var pendingDifficulty = null;
     //private members
     this.socket = options.socket;
 
@@ -139,9 +139,9 @@ var StratumClient = function(options){
                 });
             }
         );
-        if (_this.lastEmittedDiff !== _this.difficulty){
-            _this.lastEmittedDiff = _this.difficulty
-            _this.emit('difficultyChanged', _this.difficulty);
+        if (_this.lastEmittedDiff !== _this.currentDifficulty){
+            _this.lastEmittedDiff = _this.currentDifficulty
+            _this.emit('difficultyChanged', _this.currentDifficulty);
         }
     }
 
@@ -193,6 +193,18 @@ var StratumClient = function(options){
         });
     }
 
+    this.enqueueNextDifficulty = function(requestedNewDifficulty) {
+        if (typeof(requestedNewDifficulty) != 'number') {
+            console.error('[StratumClient.enqueueNextDifficulty] given difficulty parameter is not a number: ['+requestedNewDifficulty+']');
+            return false;
+        } else {
+            console.log('[StratumClient.enqueueNextDifficulty] next difficulty should be: ['+requestedNewDifficulty+']');
+            pendingDifficulty = requestedNewDifficulty;
+            return true;
+        }
+        
+
+    };
 
     //public members
 
@@ -206,26 +218,31 @@ var StratumClient = function(options){
             return false;
         }
 
-        if (difficulty !== this.difficulty) {
-            this.difficulty = difficulty;
-            sendJson({
-                id    : null,
-                method: "mining.set_difficulty",
-                params: [difficulty]//[512],
-            });
-            return true;
-        } else {
+        if (difficulty === this.difficulty)
             return false;
-        }
+
+        _this.difficulty = difficulty;
+        sendJson({
+            id    : null,
+            method: "mining.set_difficulty",
+            params: [difficulty]//[512],
+        });
+        return true;
+
 
     };
 
     this.sendMiningJob = function(jobParams){
+        if (pendingDifficulty !== null){
+            _this.sendDifficulty(pendingDifficulty);
+            pendingDifficulty = null;
+        }
         sendJson({
             id    : null,
             method: "mining.notify",
             params: jobParams
         });
+
     };
 };
 StratumClient.prototype.__proto__ = events.EventEmitter.prototype;