1 files changed, 112 insertions, 0 deletions
diff --git a/dom/ipc/SharedMessageBody.h b/dom/ipc/SharedMessageBody.h
new file mode 100644
index 0000000000..2c82473678
--- /dev/null
+++ b/dom/ipc/SharedMessageBody.h
@@ -0,0 +1,112 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_SharedMessageBody_h
+#define mozilla_dom_SharedMessageBody_h
+
+#include "mozilla/dom/ipc/StructuredCloneData.h"
+#include "mozilla/Maybe.h"
+
+namespace mozilla {
+
+namespace ipc {
+class PBackgroundChild;
+}
+
+namespace dom {
+
+class MessagePort;
+class RefMessageBody;
+class RefMessageBodyService;
+
+class SharedMessageBody final {
+ public:
+  NS_INLINE_DECL_REFCOUNTING(SharedMessageBody)
+
+  SharedMessageBody(
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring,
+      const Maybe<nsID>& aAgentClusterId);
+
+  // Note that the populated MessageData borrows the underlying
+  // JSStructuredCloneData from the SharedMessageBody, so the caller is
+  // required to ensure that the MessageData instances are destroyed prior to
+  // the SharedMessageBody instances.
+  static void FromSharedToMessageChild(
+      mozilla::ipc::PBackgroundChild* aBackgroundManager,
+      SharedMessageBody* aData, MessageData& aMessage);
+  static void FromSharedToMessagesChild(
+      mozilla::ipc::PBackgroundChild* aBackgroundManager,
+      const nsTArray<RefPtr<SharedMessageBody>>& aData,
+      nsTArray<MessageData>& aArray);
+
+  // Const MessageData.
+  static already_AddRefed<SharedMessageBody> FromMessageToSharedChild(
+      MessageData& aMessage,
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring =
+          StructuredCloneHolder::TransferringSupported);
+  // Non-const MessageData.
+  static already_AddRefed<SharedMessageBody> FromMessageToSharedChild(
+      const MessageData& aMessage,
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring =
+          StructuredCloneHolder::TransferringSupported);
+  // Array of MessageData objects
+  static bool FromMessagesToSharedChild(
+      nsTArray<MessageData>& aArray,
+      FallibleTArray<RefPtr<SharedMessageBody>>& aData,
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring =
+          StructuredCloneHolder::TransferringSupported);
+
+  // Note that the populated MessageData borrows the underlying
+  // JSStructuredCloneData from the SharedMessageBody, so the caller is
+  // required to ensure that the MessageData instances are destroyed prior to
+  // the SharedMessageBody instances.
+  static bool FromSharedToMessagesParent(
+      mozilla::ipc::PBackgroundParent* aManager,
+      const nsTArray<RefPtr<SharedMessageBody>>& aData,
+      nsTArray<MessageData>& aArray);
+
+  static already_AddRefed<SharedMessageBody> FromMessageToSharedParent(
+      MessageData& aMessage,
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring =
+          StructuredCloneHolder::TransferringSupported);
+  static bool FromMessagesToSharedParent(
+      nsTArray<MessageData>& aArray,
+      FallibleTArray<RefPtr<SharedMessageBody>>& aData,
+      StructuredCloneHolder::TransferringSupport aSupportsTransferring =
+          StructuredCloneHolder::TransferringSupported);
+
+  enum ReadMethod {
+    StealRefMessageBody,
+    KeepRefMessageBody,
+  };
+
+  void Read(JSContext* aCx, JS::MutableHandle<JS::Value> aValue,
+            RefMessageBodyService* aRefMessageBodyService,
+            ReadMethod aReadMethod, ErrorResult& aRv);
+
+  void Write(JSContext* aCx, JS::Handle<JS::Value> aValue,
+             JS::Handle<JS::Value> aTransfers, nsID& aPortID,
+             RefMessageBodyService* aRefMessageBodyService, ErrorResult& aRv);
+
+  bool TakeTransferredPortsAsSequence(
+      Sequence<OwningNonNull<mozilla::dom::MessagePort>>& aPorts);
+
+ private:
+  ~SharedMessageBody() = default;
+
+  UniquePtr<ipc::StructuredCloneData> mCloneData;
+
+  RefPtr<RefMessageBody> mRefData;
+  Maybe<nsID> mRefDataId;
+
+  const StructuredCloneHolder::TransferringSupport mSupportsTransferring;
+  const Maybe<nsID> mAgentClusterId;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_SharedMessageBody_h