From 10fce032b77e6cfd0a8fe66c0bf6f3bb0bd9c545 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Mon, 4 Jan 2016 15:12:50 -0800
Subject: [PATCH] improve locatorHashes. fix utils ref in tx-pool. add
 utils.hash.

---
 lib/bcoin/chain.js     | 27 +++++++++++++++++++++------
 lib/bcoin/fullchain.js |  9 +++++----
 lib/bcoin/pool.js      | 10 ++++------
 lib/bcoin/tx-pool.js   |  1 +
 lib/bcoin/utils.js     | 22 ++++++++++++++++++++++
 5 files changed, 53 insertions(+), 16 deletions(-)

diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index 42404433..f579b044 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -627,12 +627,27 @@ Chain.prototype.getStartHeight = function getStartHeight() {
   return 0;
 };
 
-Chain.prototype.locatorHashes = function locatorHashes(start) {
-  if (start != null) {
-    if (typeof start === 'number')
-      start = this.byHeight(start);
-    else
-      start = this.byHash(start);
+Chain.prototype.locatorHashes = function locatorHashes(obj) {
+  var start;
+
+  if (obj) {
+    if (Array.isArray(obj))
+      obj = utils.toHex(obj);
+    else if (obj.hash)
+      obj = obj.hash('hex');
+  }
+
+  // Convert the start to indexes
+  if (obj != null) {
+    if (typeof obj === 'string') {
+      start = this.byHash(obj);
+      if (!start)
+        return [obj];
+    } else if (typeof obj === 'number') {
+      start = this.byHeight(obj);
+    }
+
+    assert(start);
 
     if (start)
       start = start.index;
diff --git a/lib/bcoin/fullchain.js b/lib/bcoin/fullchain.js
index 9f914bf6..6d585354 100644
--- a/lib/bcoin/fullchain.js
+++ b/lib/bcoin/fullchain.js
@@ -431,14 +431,15 @@ Chain.prototype.locatorHashes = function locatorHashes(start) {
   }
 
   if (typeof start === 'string') {
-    // Hash
-    if (this.index.heights[start] != null)
-      top = this.index.heights[start];
+    top = this.index.heights[start];
+    if (top == null)
+      return [start];
   } else if (typeof start === 'number') {
-    // Height
     top = start;
   }
 
+  assert(chain[top]);
+
   i = top;
   for (;;) {
     if (chain[i])
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 469e7d63..9b5dd87b 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -353,12 +353,10 @@ Pool.prototype._handleHeaders = function _handleHeaders(headers, peer) {
   }
 
   // Restart the getheaders process
-  if (last && headers.length === 2000) {
-    // Ideally we should use chain.locatorHashes here, but we can't since we
-    // didn't add the headers to the chain (in non-headers-first mode)
-    // peer.loadHeaders(this.chain.locatorHashes(last), null);
-    peer.loadHeaders([last.hash('hex')], null);
-  }
+  // chain.locatorHashes will return [last.hash('hex')] here for now because
+  // the headers have not been added to the chain in non-headers-first mode.
+  if (last && headers.length === 2000)
+    peer.loadHeaders(this.chain.locatorHashes(last), null);
 
   // Push our getdata packet
   this._scheduleRequests();
diff --git a/lib/bcoin/tx-pool.js b/lib/bcoin/tx-pool.js
index 1ec28b78..0d1a2e5e 100644
--- a/lib/bcoin/tx-pool.js
+++ b/lib/bcoin/tx-pool.js
@@ -7,6 +7,7 @@
 var bn = require('bn.js');
 var inherits = require('inherits');
 var bcoin = require('../bcoin');
+var utils = bcoin.utils;
 var assert = bcoin.utils.assert;
 var EventEmitter = require('events').EventEmitter;
 
diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 038e8685..96f4f866 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -830,3 +830,25 @@ utils.testTarget = function testTarget(target, hash) {
 utils.now = function now() {
   return +new Date() / 1000 | 0;
 };
+
+utils.hash = function hash(obj, enc) {
+  if (!obj)
+    return obj;
+
+  if (typeof obj === 'string')
+    return enc === 'hex' ? obj : utils.toArray(obj, 'hex');
+
+  if (Array.isArray(obj))
+    return enc === 'hex' ? utils.toHex(obj) : obj;
+
+  if (typeof obj.hash === 'function')
+    return obj.hash(enc);
+
+  if (obj.hash)
+    return hash(obj.hash, enc);
+
+  if (obj._hash)
+    return hash(obj._hash, enc);
+
+  return obj;
+};