dgram: implement socket.bind({ fd })

dgram: Implement binding an existing `fd`. Allow pass a `fd` property
to `socket.bind()` in dgram.
src: Add `UDPWrap::Open`

PR-URL: https://github.com/nodejs/node/pull/21745
Fixes: https://github.com/nodejs/node/issues/14961
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 55 insertions, 0 deletions

diff --git a/test/parallel/test-dgram-bind-fd-error.js b/test/parallel/test-dgram-bind-fd-error.js
new file mode 100644
index 0000000000..efe0e43d7b
--- /dev/null
+++ b/test/parallel/test-dgram-bind-fd-error.js
@@ -0,0 +1,55 @@
+// Flags: --expose-internals
+'use strict';
+const common = require('../common');
+if (common.isWindows)
+  common.skip('Does not support binding fd on Windows');
+
+const dgram = require('dgram');
+const assert = require('assert');
+const { kStateSymbol } = require('internal/dgram');
+const { TCP, constants } = process.binding('tcp_wrap');
+const TYPE = 'udp4';
+
+// Throw when the fd is occupied according to https://github.com/libuv/libuv/pull/1851.
+{
+  const socket = dgram.createSocket(TYPE);
+
+  socket.bind(common.mustCall(() => {
+    const anotherSocket = dgram.createSocket(TYPE);
+    const { handle } = socket[kStateSymbol];
+
+    common.expectsError(() => {
+      anotherSocket.bind({
+        fd: handle.fd,
+      });
+    }, {
+      code: 'EEXIST',
+      type: Error,
+      message: /^open EEXIST$/
+    });
+
+    socket.close();
+  }));
+}
+
+// Throw when the type of fd is not "UDP".
+{
+  const handle = new TCP(constants.SOCKET);
+  handle.listen();
+
+  const fd = handle.fd;
+  assert.notStrictEqual(fd, -1);
+
+  const socket = new dgram.createSocket(TYPE);
+  common.expectsError(() => {
+    socket.bind({
+      fd,
+    });
+  }, {
+    code: 'ERR_INVALID_FD_TYPE',
+    type: TypeError,
+    message: /^Unsupported fd type: TCP$/
+  });
+
+  handle.close();
+}