chain refactoring.

lib/bcoin/chain.js

@@ -62,10 +62,28 @@ Chain.prototype._init = function _init() {
   var self = this;
 
   // Hook into events for debugging
-  this.on('block', function(block, entry, peer) {
-    // var host = peer ? peer.host : 'unknown';
-    // utils.debug('Block %s (%d) added to chain (%s)',
-    //   utils.revHex(entry.hash), entry.height, host);
+  // this.on('block', function(block, entry, peer) {
+  //   var host = peer ? peer.host : 'unknown';
+  //   utils.debug('Block %s (%d) added to chain (%s)',
+  //     utils.revHex(entry.hash), entry.height, host);
+  // });
+
+  this.on('competitor', function(block, entry, peer) {
+    var host = peer ? peer.host : 'unknown';
+    utils.debug('Heads up: Competing chain at height %d:'
+      + ' tip-height=%d competitor-height=%d'
+      + ' tip-hash=%s competitor-hash=%s'
+      + ' tip-chainwork=%s competitor-chainwork=%s'
+      + ' chainwork-diff=%s (%s)',
+      entry.height,
+      utils.revHex(self.tip.hash),
+      utils.revHex(entry.hash),
+      self.tip.height,
+      entry.height,
+      self.tip.chainwork.toString(),
+      entry.chainwork.toString(),
+      self.tip.chainwork.sub(entry.chainwork).toString(),
+      host);
   });
 
   this.on('resolved', function(block, entry, peer) {
@@ -863,36 +881,14 @@ Chain.prototype._reorganize = function _reorganize(entry, block, callback) {
   });
 };
 
-Chain.prototype._addEntry = function _addEntry(entry, block, callback) {
-  // Set main chain only if chainwork is higher.
-  // Add the block but do _not_ connect the inputs.
-  if (entry.chainwork.cmp(this.tip.chainwork) <= 0) {
-    return this.db.save(entry, block, false, function(err) {
-      if (err)
-        return callback(err);
-
-      return callback(null, false);
-    });
-  }
-
-  // Attempt to add block to the chain index.
-  return this._setBestChain(entry, block, function(err) {
-    if (err)
-      return callback(err);
-
-    return callback(null, true);
-  });
-};
-
 Chain.prototype._setBestChain = function _setBestChain(entry, block, callback) {
   var self = this;
 
-  this.lastUpdate = utils.now();
-
   function done(err) {
     if (err)
       return callback(err);
 
+    // Save block and connect inputs.
     self.db.save(entry, block, true, function(err) {
       if (err)
         return callback(err);
@@ -905,20 +901,45 @@ Chain.prototype._setBestChain = function _setBestChain(entry, block, callback) {
 
       self.emit('tip', entry);
 
-      return callback();
+      // Return true (added to the main chain)
+      return callback(null, true);
     });
   }
 
+  // Update the timestamp to
+  // maintain a time delta of blocks.
+  this.lastUpdate = utils.now();
+
+  // We don't have a genesis block yet.
   if (!this.tip) {
     if (entry.hash !== network.genesis.hash)
       return utils.asyncify(callback)(new Error('Bad genesis block.'));
 
-    done();
-  } else if (entry.prevBlock === this.tip.hash) {
-    done();
-  } else {
-    self._reorganize(entry, block, done);
+    return done();
   }
+
+  // The block is on a side chain if the
+  // chainwork is less than or equal to
+  // our tip's. Add the block but do _not_
+  // connect the inputs.
+  if (entry.chainwork.cmp(this.tip.chainwork) <= 0) {
+    return this.db.save(entry, block, false, function(err) {
+      if (err)
+        return callback(err);
+
+      // Return false (added to side chain)
+      return callback(null, false);
+    });
+  }
+
+  // Everything is in order.
+  if (entry.prevBlock === this.tip.hash)
+    return done();
+
+  // A higher fork has arrived.
+  // Time to reorganize the chain.
+  utils.debug('WARNING: Reorganizing chain.');
+  return this._reorganize(entry, block, done);
 };
 
 Chain.prototype.reset = function reset(height, callback, force) {
@@ -1214,7 +1235,7 @@ Chain.prototype.add = function add(initial, peer, callback, force) {
           }, prev);
 
           // Attempt to add block to the chain index.
-          self._addEntry(entry, block, function(err, mainChain) {
+          self._setBestChain(entry, block, function(err, mainChain) {
             if (err)
               return done(err);
 
@@ -1226,6 +1247,8 @@ Chain.prototype.add = function add(initial, peer, callback, force) {
             // orphan) only if it is on the main chain.
             if (mainChain)
               self.emit('block', block, entry, peer);
+            else
+              self.emit('competitor', block, entry, peer);
 
             if (block.hash('hex') !== initial.hash('hex'))
               self.emit('resolved', block, entry, peer);

lib/bcoin/chainblock.js

@@ -242,6 +242,10 @@ ChainBlock.prototype.getMedianTimeAsync = function getMedianTimeAsync(callback)
   });
 };
 
+ChainBlock.prototype.__defineGetter__('rhash', function() {
+  return utils.revHex(this.hash);
+});
+
 ChainBlock.prototype.toRaw = function toRaw() {
   var p = new BufferWriter();
 

lib/bcoin/chaindb.js

@@ -353,7 +353,6 @@ ChainDB.prototype.save = function save(entry, block, connect, callback) {
 
   batch.put('c/b/' + entry.hash, height);
   batch.put('c/c/' + entry.hash, entry.toRaw());
-  batch.put('c/n/' + entry.prevBlock, hash);
 
   this.cacheHash.set(entry.hash, entry);
 
@@ -367,6 +366,7 @@ ChainDB.prototype.save = function save(entry, block, connect, callback) {
 
   this.cacheHeight.set(entry.height, entry);
 
+  batch.put('c/n/' + entry.prevBlock, hash);
   batch.put('c/h/' + pad32(entry.height), hash);
   batch.put('c/t', hash);
 
@@ -399,7 +399,7 @@ ChainDB.prototype.getTip = function getTip(callback) {
 
 ChainDB.prototype.connect = function connect(block, callback) {
   var self = this;
-  var batch;
+  var batch, hash;
 
   this._ensureEntry(block, function(err, entry) {
     if (err)
@@ -409,9 +409,11 @@ ChainDB.prototype.connect = function connect(block, callback) {
       return callback();
 
     batch = self.db.batch();
+    hash = new Buffer(entry.hash, 'hex');
 
-    batch.put('c/h/' + pad32(entry.height), new Buffer(entry.hash, 'hex'));
-    batch.put('c/t', new Buffer(entry.hash, 'hex'));
+    batch.put('c/n/' + entry.prevBlock, hash);
+    batch.put('c/h/' + pad32(entry.height), hash);
+    batch.put('c/t', hash);
 
     self.cacheHeight.set(entry.height, entry);
 
@@ -443,6 +445,7 @@ ChainDB.prototype.disconnect = function disconnect(block, callback) {
 
     batch = self.db.batch();
 
+    batch.del('c/n/' + entry.prevBlock);
     batch.del('c/h/' + pad32(entry.height));
     batch.put('c/t', new Buffer(entry.prevBlock, 'hex'));