From 84277ea84544d9999e7fea3eec30abada673f7c8 Mon Sep 17 00:00:00 2001
From: Krishna Rajendran <krishna@emptybox.org>
Date: Wed, 17 Mar 2010 01:13:45 -0400
Subject: [PATCH] Check for callback argument in PTR lookup

---
 src/node_dns.cc           | 5 +++++
 test/disabled/test-dns.js | 5 ++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/node_dns.cc b/src/node_dns.cc
index 8bb440a258..3898c1aff0 100644
--- a/src/node_dns.cc
+++ b/src/node_dns.cc
@@ -443,6 +443,11 @@ static Handle<Value> Reverse(const Arguments& args) {
           String::New("Argument must be a string.")));
   }
 
+  if (!args[1]->IsFunction()) {
+    return ThrowException(Exception::Error(
+          String::New("Missing callback argument")));
+  }
+
   String::Utf8Value ip_address(args[0]->ToString());
 
   union {
diff --git a/test/disabled/test-dns.js b/test/disabled/test-dns.js
index 7985728d22..f43ba5b832 100644
--- a/test/disabled/test-dns.js
+++ b/test/disabled/test-dns.js
@@ -8,7 +8,10 @@ var dns = require("dns"),
 
 assert.throws(function () {
   dns.resolve('google.com', 'A');
-})
+});
+assert.throws(function () {
+  dns.resolve('127.0.0.1', 'PTR');
+});
 
 
 var hosts = ['example.com', 'example.org',