new verifyContext.

lib/bcoin/chain.js

@@ -666,11 +666,9 @@ Chain.prototype.resetTime = function resetTime(ts) {
   return this.resetHeight(entry.height);
 };
 
-Chain.prototype.add = function add(block, peer, callback) {
+Chain.prototype.add = function add(initial, peer, callback) {
   var self = this;
-  var initial = block;
   var code = Chain.codes.unchanged;
-  var hash, prevHash, prevHeight, entry, tip, existing, checkpoint, prev;
   var total = 0;
 
   callback = utils.asyncify(callback);
@@ -678,10 +676,10 @@ Chain.prototype.add = function add(block, peer, callback) {
   if (this._locked)
     return callback(null, total);
 
-  // (function next(block) {
-  (function next() {
-    hash = block.hash('hex');
-    prevHash = block.prevBlock;
+  (function next(block) {
+    var hash = block.hash('hex');
+    var prevHash = block.prevBlock;
+    var prevHeight, entry, existing, checkpoint, prev;
 
     // Find the previous block height/index.
     prevHeight = self.heightLookup[prevHash];
@@ -746,84 +744,93 @@ Chain.prototype.add = function add(block, peer, callback) {
       height: prevHeight + 1
     });
 
-    // Add entry if we do not have it (or if
-    // there is another entry at its height)
+    // Fork at checkpoint
+    // Block did not match the checkpoint. The
+    // chain could be reset to the last sane
+    // checkpoint, but it really isn't necessary,
+    // so we don't do it. The misbehaving peer has
+    // been killed and hopefully we find a peer
+    // who isn't trying to fool us.
+    checkpoint = network.checkpoints[entry.height];
+    if (checkpoint) {
+      self.emit('checkpoint', entry.height, entry.hash, checkpoint);
+      if (hash !== checkpoint) {
+        // Resetting to the last checkpoint _really_ isn't
+        // necessary (even bitcoind doesn't do it), but it
+        // could be used if you want to be on the overly
+        // safe (see: paranoid) side.
+        // this.resetLastCheckpoint(entry.height);
+        code = Chain.codes.badCheckpoint;
+        self.emit('fork', {
+          height: entry.height,
+          expected: network.checkpoints[entry.height],
+          received: entry.hash,
+          checkpoint: true
+        });
+        return done(null, code);
+      }
+    }
+
+    // See if the entry already exists.
     existing = self.db.get(entry.height);
-    if (!existing || existing.hash !== hash) {
-      assert(self.heightLookup[entry.hash] == null);
+
+    // Entry already exists.
+    if (existing) {
+      // We already have this block. Do regular
+      // orphan resolution (won't do anything).
+      if (existing.hash === hash)
+        return handleOrphans();
 
       // A valid block with an already existing
       // height came in, that spells fork. We
       // don't store by hash so we can't compare
       // chainworks. We reset the chain, find a
       // new peer, and wait to see who wins.
-      if (existing) {
-        // The tip has more chainwork, it is a
-        // higher height than the entry. This is
-        // not an alternate tip. Ignore it.
-        if (self.tip.chainwork.cmp(entry.chainwork) > 0) {
-          code = Chain.codes.unchanged;
-          return done(null, code);
-        }
-        // Get _our_ tip as opposed to
-        // the attempted alternate tip.
-        tip = existing;
-        // The block has equal chainwork (an
-        // alternate tip). Reset the chain, find
-        // a new peer, and wait to see who wins.
-        self._locked = true;
-        return self._removeBlock(tip.hash, function(err) {
-          self._locked = false;
-          if (err)
-            return done(err);
-          self.resetHeight(entry.height - 1);
-          self.emit('fork', {
-            height: prevHeight + 1,
-            expected: tip.hash,
-            received: hash,
-            checkpoint: false
-          }, peer);
-          code = Chain.codes.forked;
-          return done(null, code);
-        });
+      assert(self.heightLookup[entry.hash] == null);
+
+      // The tip has more chainwork, it is a
+      // higher height than the entry. This is
+      // not an alternate tip. Ignore it.
+      if (self.tip.chainwork.cmp(entry.chainwork) > 0) {
+        code = Chain.codes.unchanged;
+        return done(null, code);
       }
 
-      // Fork at checkpoint
-      // Block did not match the checkpoint. The
-      // chain could be reset to the last sane
-      // checkpoint, but it really isn't necessary,
-      // so we don't do it. The misbehaving peer has
-      // been killed and hopefully we find a peer
-      // who isn't trying to fool us.
-      checkpoint = network.checkpoints[entry.height];
-      if (checkpoint) {
-        self.emit('checkpoint', entry.height, entry.hash, checkpoint);
-        if (hash !== checkpoint) {
-          // Resetting to the last checkpoint _really_ isn't
-          // necessary (even bitcoind doesn't do it), but it
-          // could be used if you want to be on the overly
-          // safe (see: paranoid) side.
-          // this.resetLastCheckpoint(entry.height);
-          code = Chain.codes.badCheckpoint;
-          self.emit('fork', {
-            height: entry.height,
-            expected: network.checkpoints[entry.height],
-            received: entry.hash,
-            checkpoint: true
-          });
-          return done(null, code);
-        }
-      }
+      // The block has equal chainwork (an
+      // alternate tip). Reset the chain, find
+      // a new peer, and wait to see who wins.
+      self._locked = true;
+      return self._removeBlock(existing.hash, function(err) {
+        self._locked = false;
+        if (err)
+          return done(err);
+        self.resetHeight(entry.height - 1);
+        self.emit('fork', {
+          height: prevHeight + 1,
+          expected: existing.hash,
+          received: hash,
+          checkpoint: false
+        }, peer);
+        code = Chain.codes.forked;
+        return done(null, code);
+      });
+    }
 
-      // Lookup previous entry.
-      prev = self.db.get(prevHeight);
-      assert(prev);
+    // Add entry if we do not have it.
+    assert(self.heightLookup[entry.hash] == null);
 
-      // Do "contextual" verification on our block
-      // now that we're certain its previous
-      // block is in the chain.
-      // self._verifyContext(block, prev, function(err, verified) {
-      if (!block.verifyContext(prev)) {
+    // Lookup previous entry.
+    prev = self.db.get(prevHeight);
+    assert(prev);
+
+    // Do "contextual" verification on our block
+    // now that we're certain its previous
+    // block is in the chain.
+    self._verifyContext(block, prev, function(err, verified) {
+      if (err)
+        return done(err);
+
+      if (!verified) {
         code = Chain.codes.invalid;
         self.emit('invalid', {
           height: prevHeight + 1,
@@ -869,9 +876,7 @@ Chain.prototype.add = function add(block, peer, callback) {
 
         handleOrphans();
       });
-    } else {
-      handleOrphans();
-    }
+    });
 
     function handleOrphans() {
       if (!self.orphan.map[hash])
@@ -884,9 +889,9 @@ Chain.prototype.add = function add(block, peer, callback) {
       self.orphan.count--;
       self.orphan.size -= block.getSize();
 
-      next();
+      next(block);
     }
-  })();
+  })(initial);
 
   function done(err, code) {
     // Failsafe for large orphan chains. Do not