dgram: generalized send queue to handle close

mcollina · cjihrig · commit 51a2041b90e5 · 2016-08-10T11:06:44.000-04:00
If the udp socket is not ready and we are accumulating messages to send, it needs to delay closing the socket when all messages are flushed. Fixes: #7061 PR-URL: #7066 Reviewed-By: Anna Henningsen <anna@addaleax.net>
diff --git a/lib/dgram.js b/lib/dgram.js
@@ -283,20 +283,25 @@ function fixBufferList(list) {
 function enqueue(self, toEnqueue) {
   // If the send queue hasn't been initialized yet, do it, and install an
   // event handler that flushes the send queue after binding is done.
-  if (!self._sendQueue) {
-    self._sendQueue = [];
-    self.once('listening', function() {
-      // Flush the send queue.
-      for (var i = 0; i < this._sendQueue.length; i++)
-        this.send.apply(self, this._sendQueue[i]);
-      this._sendQueue = undefined;
-    });
+  if (!self._queue) {
+    self._queue = [];
+    self.once('listening', clearQueue);
   }
-  self._sendQueue.push(toEnqueue);
+  self._queue.push(toEnqueue);
   return;
 }
 
 
+function clearQueue() {
+  const queue = this._queue;
+  this._queue = undefined;
+
+  // Flush the send queue.
+  for (var i = 0; i < queue.length; i++)
+    queue[i]();
+}
+
+
 // valid combinations
 // send(buffer, offset, length, port, address, callback)
 // send(buffer, offset, length, port, address)
@@ -353,7 +358,7 @@ Socket.prototype.send = function(buffer,
   // If the socket hasn't been bound yet, push the outbound packet onto the
   // send queue and send after binding is complete.
   if (self._bindState != BIND_STATE_BOUND) {
-    enqueue(self, [list, port, address, callback]);
+    enqueue(self, self.send.bind(self, list, port, address, callback));
     return;
   }
 
@@ -407,10 +412,15 @@ function afterSend(err, sent) {
   this.callback(err, sent);
 }
 
-
 Socket.prototype.close = function(callback) {
   if (typeof callback === 'function')
     this.on('close', callback);
+
+  if (this._queue) {
+    this._queue.push(this.close.bind(this));
+    return this;
+  }
+
   this._healthCheck();
   this._stopReceiving();
   this._handle.close();
diff --git a/test/parallel/test-dgram-close-in-listening.js b/test/parallel/test-dgram-close-in-listening.js
@@ -0,0 +1,18 @@
+'use strict';
+// Ensure that if a dgram socket is closed before the sendQueue is drained
+// will not crash
+
+const common = require('../common');
+const dgram = require('dgram');
+
+const buf = Buffer.alloc(1024, 42);
+
+const socket = dgram.createSocket('udp4');
+
+socket.on('listening', function() {
+  socket.close();
+});
+
+// adds a listener to 'listening' to send the data when
+// the socket is available
+socket.send(buf, 0, buf.length, common.PORT, 'localhost');
