dgram: fix double implicit bind error

Calling send() on an unbound socket forces an implicit bind to
a random port.

332fea5 made the 'listening' event asynchronous. Unfortunately,
it also introduced a bug where the implicit bind was tried more
than once if send() was called again before the first bind operation
completed.

Address that by keeping track of the bind status and making sure that
bind() is called only once.

Fixes #4499.

1 files changed, 49 insertions, 0 deletions

diff --git a/test/simple/test-dgram-implicit-bind.js b/test/simple/test-dgram-implicit-bind.js
new file mode 100644
index 0000000000..6039629c41
--- /dev/null
+++ b/test/simple/test-dgram-implicit-bind.js
@@ -0,0 +1,49 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common');
+var assert = require('assert');
+var dgram = require('dgram');
+
+var source = dgram.createSocket('udp4');
+var target = dgram.createSocket('udp4');
+var messages = 0;
+
+process.on('exit', function() {
+  assert.equal(messages, 2);
+});
+
+target.on('message', function(buf) {
+  if (buf.toString() === 'abc') ++messages;
+  if (buf.toString() === 'def') ++messages;
+  if (messages === 2) {
+    source.close();
+    target.close();
+  }
+});
+
+target.on('listening', function() {
+  // Second .send() call should not throw a bind error.
+  source.send(Buffer('abc'), 0, 3, common.PORT, '127.0.0.1');
+  source.send(Buffer('def'), 0, 3, common.PORT, '127.0.0.1');
+});
+
+target.bind(common.PORT);