cluster: allow shared reused dgram sockets

Allow listening on reused dgram ports in cluster workers.

Fix: https://github.com/joyent/node/issues/9261
PR-URL: https://github.com/nodejs/node/pull/2548
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 25 insertions, 14 deletions

diff --git a/lib/cluster.js b/lib/cluster.js
index cbccd02605..84d7c766cb 100644
--- a/lib/cluster.js
+++ b/lib/cluster.js
@@ -57,7 +57,7 @@ Worker.prototype.isConnected = function isConnected() {
 
 // Master/worker specific methods are defined in the *Init() functions.
 
-function SharedHandle(key, address, port, addressType, backlog, fd) {
+function SharedHandle(key, address, port, addressType, backlog, fd, flags) {
   this.key = key;
   this.workers = [];
   this.handle = null;
@@ -66,7 +66,7 @@ function SharedHandle(key, address, port, addressType, backlog, fd) {
   // FIXME(bnoordhuis) Polymorphic return type for lack of a better solution.
   var rval;
   if (addressType === 'udp4' || addressType === 'udp6')
-    rval = dgram._createSocketHandle(address, port, addressType, fd);
+    rval = dgram._createSocketHandle(address, port, addressType, fd, flags);
   else
     rval = net._createServerHandle(address, port, addressType, fd);
 
@@ -438,7 +438,8 @@ function masterInit() {
     var args = [message.address,
                 message.port,
                 message.addressType,
-                message.fd];
+                message.fd,
+                message.index];
     var key = args.join(':');
     var handle = handles[key];
     if (handle === undefined) {
@@ -456,7 +457,8 @@ function masterInit() {
                                               message.port,
                                               message.addressType,
                                               message.backlog,
-                                              message.fd);
+                                              message.fd,
+                                              message.flags);
     }
     if (!handle.data) handle.data = message.data;
 
@@ -485,7 +487,7 @@ function masterInit() {
     cluster.emit('listening', worker, info);
   }
 
-  // Round-robin only. Server in worker is closing, remove from list.
+  // Server in worker is closing, remove from list.
   function close(worker, message) {
     var key = message.key;
     var handle = handles[key];
@@ -500,6 +502,7 @@ function masterInit() {
 
 function workerInit() {
   var handles = {};
+  var indexes = {};
 
   // Called from src/node.js
   cluster._setupWorker = function() {
@@ -528,15 +531,22 @@ function workerInit() {
   };
 
   // obj is a net#Server or a dgram#Socket object.
-  cluster._getServer = function(obj, address, port, addressType, fd, cb) {
-    var message = {
-      addressType: addressType,
-      address: address,
-      port: port,
+  cluster._getServer = function(obj, options, cb) {
+    const key = [ options.address,
+                options.port,
+                options.addressType,
+                options.fd ].join(':');
+    if (indexes[key] === undefined)
+      indexes[key] = 0;
+    else
+      indexes[key]++;
+
+    const message = util._extend({
       act: 'queryServer',
-      fd: fd,
+      index: indexes[key],
       data: null
-    };
+    }, options);
+
     // Set custom data on handle (i.e. tls tickets key)
     if (obj._getServerData) message.data = obj._getServerData();
     send(message, function(reply, handle) {
@@ -549,9 +559,9 @@ function workerInit() {
     });
     obj.once('listening', function() {
       cluster.worker.state = 'listening';
-      var address = obj.address();
+      const address = obj.address();
       message.act = 'listening';
-      message.port = address && address.port || port;
+      message.port = address && address.port || options.port;
       send(message);
     });
   };
@@ -563,6 +573,7 @@ function workerInit() {
     // closed. Avoids resource leaks when the handle is short-lived.
     var close = handle.close;
     handle.close = function() {
+      send({ act: 'close', key: key });
       delete handles[key];
       return close.apply(this, arguments);
     };