From ca2609b7e7012362965b4f65f73d923b06312891 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Sun, 18 May 2014 10:34:38 -0500
Subject: [PATCH] util: bignum - use toArray instead of +toString.

Signed-off-by: Fedor Indutny <fedor@indutny.com>
---
 lib/bcoin/utils.js | 40 ++++++++++++++++++++++++++++++++++------
 1 file changed, 34 insertions(+), 6 deletions(-)

diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 319b00f8..9cf9c168 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -180,9 +180,23 @@ utils.writeU64 = function writeU64(dst, num, off) {
   if (!off)
     off = 0;
 
-  new bn(num).toArray().reverse().forEach(function(ch, i) {
-    dst[off + i] = ch;
-  });
+  var num = new bn(num);
+
+  var left = num.shrn(32).toArray();
+  while (left.length < 4) left.unshift(0);
+
+  var right = num.maskn(32).toArray();
+  while (right.length < 4) right.unshift(0);
+
+  dst[off] = right[3];
+  dst[off + 1] = right[2];
+  dst[off + 2] = right[1];
+  dst[off + 3] = right[0];
+
+  dst[off + 4] = left[3];
+  dst[off + 5] = left[2];
+  dst[off + 6] = left[1];
+  dst[off + 7] = left[0];
 
   return 8;
 };
@@ -209,9 +223,23 @@ utils.writeU64BE = function writeU64BE(dst, num, off) {
   if (!off)
     off = 0;
 
-  new bn(num).toArray().forEach(function(ch, i) {
-    dst[off + i] = ch;
-  });
+  var num = new bn(num);
+
+  var left = num.shrn(32).toArray();
+  while (left.length < 4) left.unshift(0);
+
+  var right = num.maskn(32).toArray();
+  while (right.length < 4) right.unshift(0);
+
+  dst[off] = left[0];
+  dst[off + 1] = left[1];
+  dst[off + 2] = left[2];
+  dst[off + 3] = left[3];
+
+  dst[off + 4] = right[0];
+  dst[off + 5] = right[1];
+  dst[off + 6] = right[2];
+  dst[off + 7] = right[3];
 
   return 8;
 };