LibWeb: Implement basic support for MessageChannel and MessagePort

This patch adds a basic initial implementation of these API's.

Since LibWeb currently doesn't support workers, this implementation of
messaging doesn't bother with serializing and deserializing messages.

1 files changed, 47 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/HTML/MessageChannel.h b/Userland/Libraries/LibWeb/HTML/MessageChannel.h
new file mode 100644
index 0000000000..9abe9b91d1
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/MessageChannel.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <LibWeb/Bindings/Wrappable.h>
+#include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/DOM/Window.h>
+#include <LibWeb/Forward.h>
+
+namespace Web::HTML {
+
+// https://html.spec.whatwg.org/multipage/web-messaging.html#message-channels
+class MessageChannel final
+    : public RefCounted<MessageChannel>
+    , public Bindings::Wrappable {
+public:
+    using WrapperType = Bindings::MessageChannelWrapper;
+
+    using RefCounted::ref;
+    using RefCounted::unref;
+
+    static NonnullRefPtr<MessageChannel> create_with_global_object(Bindings::WindowObject& global_object)
+    {
+        return adopt_ref(*new MessageChannel(global_object));
+    }
+
+    virtual ~MessageChannel() override;
+
+    MessagePort* port1() { return m_port1; }
+    MessagePort const* port1() const { return m_port1; }
+
+    MessagePort* port2() { return m_port2; }
+    MessagePort const* port2() const { return m_port2; }
+
+private:
+    explicit MessageChannel(Bindings::WindowObject&);
+
+    RefPtr<MessagePort> m_port1;
+    RefPtr<MessagePort> m_port2;
+};
+
+}