Avoid recursive calls to _fetchRecData

lib/par2.js

@@ -277,12 +277,14 @@ var GFWrapper = {
 			// buffer can be used for fetching
 			var nextIdx = idx + this.recData.length;
 			if(nextIdx < this.recoverySlices.length)
-				this._fetchRecData(nextIdx);
+				// defer callback to avoid recursive nesting (since _fetchRecData can call _markRecDataConsumed)
+				setImmediate(this._fetchRecData.bind(this, nextIdx));
 			else {
 				// if we've consumed everything, free up recovery data memory
 				this.recData[groupIdx] = null;
 				if(this._isRecoveryProcessed() && this.recCompleteCb)
-					this.recCompleteCb();
+					// ensure this callback is called *after* any other pending callbacks
+					process.nextTick(this.recCompleteCb.bind(this));
 			}
 		}
 	},
@@ -314,30 +316,15 @@ var GFWrapper = {
 					bufs[i] = bufferSlice.call(self.recData[baseBufIdx + i], 0, self.chunkSize);
 				}
 
-				var updateCallbackCount = 0;
 				self.recDataHashers[hasherIdx].update(bufs, function() {
-					updateCallbackCount++;
 					// remove refs on buffers
 					for(var i=0; i<numBufs; i++) {
 						var _i = i+hashBaseIdx;
 						self._markRecDataConsumed(_i);
 
 						// notify that hashing is complete
-						if(self.recDataHashCb[_i]) {
-							// debug weird failure
-							if(self.recDataHashCb[_i] === true)
-								throw new Error('Trying to call rec-data hash callback more than once! [Debug] ' + JSON.stringify({
-									hashBaseIdx: hashBaseIdx,
-									hashIdx: i,
-									invokeIdx: idx,
-									numBufs: numBufs,
-									recSlices: self.recoverySlices.length,
-									callbackCount: updateCallbackCount,
-									batchSize: self._gfOpts.hashBatchSize,
-									batchCbTypes: self.recDataHashCb.slice(hashBaseIdx, hashBaseIdx+numBufs).map(function(c){return typeof c}).join(',')
-								}));
+						if(self.recDataHashCb[_i])
 							self.recDataHashCb[_i](_i);
-						}
 						self.recDataHashCb[_i] = true;
 					}
 				});