From f8193ab3c46475486eab38543650e2388bd3aedc Mon Sep 17 00:00:00 2001
From: Timothy J Fontaine <tjfontaine@gmail.com>
Date: Wed, 22 May 2013 11:32:54 -0700
Subject: [PATCH] timers: use uv_now instead of Date.now

This saves a few calls to gettimeofday which can be expensive, and
potentially subject to clock drift. Instead use the loop time which
uses hrtime internally.

fixes #5497
---
 lib/timers.js     | 8 ++++----
 lib/tls.js        | 4 +++-
 src/timer_wrap.cc | 9 +++++++++
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/lib/timers.js b/lib/timers.js
index 2b0745c5a49afa..1412928c51f938 100644
--- a/lib/timers.js
+++ b/lib/timers.js
@@ -45,7 +45,7 @@ var lists = {};
 // the main function - creates lists on demand and the watchers associated
 // with them.
 function insert(item, msecs) {
-  item._idleStart = Date.now();
+  item._idleStart = Timer.now();
   item._idleTimeout = msecs;
 
   if (msecs < 0) return;
@@ -75,7 +75,7 @@ function listOnTimeout() {
 
   debug('timeout callback %d', msecs);
 
-  var now = Date.now();
+  var now = Timer.now();
   debug('now: %s', now);
 
   var first;
@@ -165,7 +165,7 @@ exports.active = function(item) {
     if (!list || L.isEmpty(list)) {
       insert(item, msecs);
     } else {
-      item._idleStart = Date.now();
+      item._idleStart = Timer.now();
       L.append(list, item);
     }
   }
@@ -277,7 +277,7 @@ var Timeout = function(after) {
 
 Timeout.prototype.unref = function() {
   if (!this._handle) {
-    var now = Date.now();
+    var now = Timer.now();
     if (!this._idleStart) this._idleStart = now;
     var delay = this._idleStart + this._idleTimeout - now;
     if (delay < 0) delay = 0;
diff --git a/lib/tls.js b/lib/tls.js
index 3af078a966e889..cc71bd9761878d 100644
--- a/lib/tls.js
+++ b/lib/tls.js
@@ -28,6 +28,8 @@ var stream = require('stream');
 var assert = require('assert').ok;
 var constants = require('constants');
 
+var Timer = process.binding('timer_wrap').Timer;
+
 var DEFAULT_CIPHERS = 'ECDHE-RSA-AES128-SHA256:AES128-GCM-SHA256:' + // TLS 1.2
                       'RC4:HIGH:!MD5:!aNULL:!EDH';                   // TLS 1.0
 
@@ -720,7 +722,7 @@ function onhandshakestart() {
 
   var self = this;
   var ssl = self.ssl;
-  var now = Date.now();
+  var now = Timer.now();
 
   assert(now >= ssl.lastHandshakeTime);
 
diff --git a/src/timer_wrap.cc b/src/timer_wrap.cc
index 88ea6b5e264db7..90bb553f050c5a 100644
--- a/src/timer_wrap.cc
+++ b/src/timer_wrap.cc
@@ -51,6 +51,8 @@ class TimerWrap : public HandleWrap {
     constructor->InstanceTemplate()->SetInternalFieldCount(1);
     constructor->SetClassName(String::NewSymbol("Timer"));
 
+    NODE_SET_METHOD(constructor, "now", Now);
+
     NODE_SET_PROTOTYPE_METHOD(constructor, "close", HandleWrap::Close);
     NODE_SET_PROTOTYPE_METHOD(constructor, "ref", HandleWrap::Ref);
     NODE_SET_PROTOTYPE_METHOD(constructor, "unref", HandleWrap::Unref);
@@ -163,6 +165,13 @@ class TimerWrap : public HandleWrap {
     MakeCallback(wrap->object_, ontimeout_sym, ARRAY_SIZE(argv), argv);
   }
 
+  static Handle<Value> Now(const Arguments& args) {
+    HandleScope scope(node_isolate);
+
+    double now = static_cast<double>(uv_now(uv_default_loop()));
+    return scope.Close(v8::Number::New(now));
+  }
+
   uv_timer_t handle_;
 };