From 0658444eb5233197fcfc03e600b3a1f621f086b2 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Sat, 9 Jan 2016 14:21:17 -0800
Subject: [PATCH] chain improvements.

---
 lib/bcoin/chain.js | 36 +++++++++++++++++++++++++---------
 lib/bcoin/pool.js  | 49 +++++++++++++++++++---------------------------
 2 files changed, 47 insertions(+), 38 deletions(-)

diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index 36b9977f..c0f7b9c5 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -109,7 +109,7 @@ Chain.messages = {
 };
 
 Chain.msg = function msg(code) {
-  return new Error(Chain.messages[code] || 'Unknown');
+  return Chain.messages[code] || 'Unknown';
 };
 
 Chain.prototype._init = function _init() {
@@ -286,13 +286,7 @@ Chain.prototype.add = function add(block, peer) {
   var initial = block;
   var code = Chain.codes.unchanged;
   var hash, prevHash, prevHeight, entry, tip;
-
-  if (this.loading) {
-    this.once('load', function() {
-      this.add(block);
-    });
-    return;
-  }
+  var total = 0;
 
   for (;;) {
     // Validate the block we want to add.
@@ -310,6 +304,22 @@ Chain.prototype.add = function add(block, peer) {
     // If the block is already known to be
     // an orphan, ignore it.
     if (this.orphan.map[prevHash]) {
+      // If the orphan chain forked, simply
+      // reset the orphans and find a new peer.
+      if (this.orphan.map[prevHash].hash('hex') !== hash) {
+        this.orphan.map = {};
+        this.orphan.bmap = {};
+        this.orphan.count = 0;
+        this.orphan.size = 0;
+        this.emit('fork', {
+          height: -1,
+          expected: this.orphan.map[prevHash].hash('hex'),
+          received: hash,
+          checkpoint: null
+        });
+        code = Chain.codes.forked;
+        break;
+      }
       code = Chain.codes.knownOrphan;
       break;
     }
@@ -325,6 +335,7 @@ Chain.prototype.add = function add(block, peer) {
       this.orphan.map[prevHash] = block;
       this.orphan.bmap[hash] = block;
       code = Chain.codes.newOrphan;
+      total++;
       break;
     }
 
@@ -398,6 +409,10 @@ Chain.prototype.add = function add(block, peer) {
       if (code !== Chain.codes.okay)
         break;
 
+      // Keep track of the number of blocks we
+      // added and the number of orphans resolved.
+      total++;
+
       // Emit our block (and potentially resolved
       // orphan) so the programmer can save it.
       this.emit('block', block, peer);
@@ -436,7 +451,10 @@ Chain.prototype.add = function add(block, peer) {
   //     this.compact();
   // }
 
-  return code;
+  if (code !== Chain.codes.okay)
+    this.emit('debug', 'Chain Error: %s', Chain.msg(code));
+
+  return total;
 };
 
 Chain.prototype.has = function has(hash, cb) {
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 5cfda7a2..c3c832d7 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -326,15 +326,21 @@ Pool.prototype._addLoader = function _addLoader() {
   });
 
   peer.on('merkleblock', function(block) {
-    self._startInterval();
-    self._startTimer();
-    self._handleBlock(block, peer);
+    // If the peer sent us a block that was added
+    // to the chain (not orphans), reset the timeout.
+    if (self._handleBlock(block, peer)) {
+      self._startInterval();
+      self._startTimer();
+    }
   });
 
   peer.on('block', function(block) {
-    self._startInterval();
-    self._startTimer();
-    self._handleBlock(block, peer);
+    // If the peer sent us a block that was added
+    // to the chain (not orphans), reset the timeout.
+    if (self._handleBlock(block, peer)) {
+      self._startInterval();
+      self._startTimer();
+    }
   });
 
   if (self.options.headers) {
@@ -499,7 +505,7 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer) {
   // Ignore if we already have
   if (this.chain.has(block)) {
     this.emit('debug', 'Already have block %s (%s)', block.height, peer.host);
-    return;
+    return false;
   }
 
   // Make sure the block is valid
@@ -507,7 +513,7 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer) {
     this.emit('debug',
       'Block verification failed for %s (%s)',
       block.rhash, peer.host);
-    return;
+    return false;
   }
 
   // Someone is sending us blocks without us requesting them.
@@ -531,38 +537,23 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer) {
         this.chain.getOrphanRoot(block)
       );
       this.emit('debug', 'Handled orphan %s (%s)', block.rhash, peer.host);
-      return;
+      return false;
     }
   }
 
   // Add to index and emit/save
-  if (this._addIndex(block, peer))
+  if (this._addIndex(block, peer)) {
     this.emit('pool block', block, peer);
+    return true;
+  }
 };
 
 Pool.prototype._addIndex = function _addIndex(block, peer) {
-  var self = this;
-  var hash, size, orphans, res;
-
-  hash = block.hash('hex');
-  size = this.chain.size();
-  orphans = this.chain.orphan.count;
-
-  res = this.chain.add(block, peer);
-
-  if (res !== bcoin.chain.codes.okay)
-    this.emit('chain-error', bcoin.chain.msg(res));
-
-  // Do not emit if nothing was added to the chain
-  if (this.chain.size() === size) {
-    if (this.chain.orphan.count > orphans)
-      return true;
-    return false;
-  }
+  var added = this.chain.add(block, peer);
 
   this.emit('chain-progress', this.chain.fillPercent(), peer);
 
-  return true;
+  return added > 0;
 };
 
 Pool.prototype.isFull = function isFull() {